Category: Networking

IEEE 802.11n was proposed in 2009 to help scale throughput of WLANs using a few different techniques known as high throughput (HT) in either the 2.4 or the 5 GHz band. 802.11n was designed to be backwards compatible with OFDM used in the 802.11g and 802.11a standards. The primary advantage of 802.11n was it’s ability to leverage multiple radios. Instead of using a single Tx/Rx radio pair (or radio chain), 802.11n devices could use multiple antennas, transmitters or receivers; a system known as multiple-input, multiple-output (MIMO). The transmitters and receivers are described in the format TxR, and 802.11n requires at least two radio chains (2×2) and supports up to a maximum of four (4×4).

In addition to the MIMO functionality, 802.11n introduced a few features to improve throughput including:

  • Channel Aggregation
  • Spatial Multiplexing (SM)
  • MAC Layer Efficiency

802.11n also introduced some features to improve the reliability of RF signals:

  • Transmit Beam Forming (TxBF)
  • Maximal-Ratio Combining (MRC)

Channel Aggregation

The 802.11n amendment first increased the 20 MHz channel throughput by increasing the number of data sub-carriers in OFDM from 48 to 52. 802.11n then goes on to allow either the use of either a single 20 MHz or a single 40 MHz channel. The aggregated channels always bond two adjacent 20 MHz channels. By bonding the channels it is able to free up the quiet space between the two original  channels for additional bandwidth. The quiet space on each end is left along to separate the 40 MHz channels. This increases the number of data sub-carriers from 52 to 108.

When the channels are aggregated it also lowers the total number of available channels. Channel aggregation shrinks the 5 GHz band from 23 non-overlapping 20 MHz channels to 11 non-overlapping 40 MHz channels. Since the 2.4 GHz band only has 3 non-overlapping channels it is not recommended nor usually attempted on that band.

Spatial Multiplexing

Channel aggregation allows for increased throughput by increasing the channel width that can be used by a single radio chain. With the advent of MIMO, the 802.11n device could have multiple radio chains waiting to be used. To further increase throughput we can multiplex, or distribute, the data across two or more radio chains, while still operating on the same channel. This is known as spatial multiplexing because the radio chains are separated by spatial diversity (they are predictably spaced out).

The spatial diversity will ultimately cause slight changes in each signal as they make their way across the free space to the receiver. If the radio signals don’t all start at the same location, then they would naturally take different paths. the 802.11n devices can also distribute the data across the multiple radio chains in a known fashion. These separate data streams can be processed as spatial streams  and can be demuxed on the receiving end. The number of spatial streams  a device can support is designated with a colon at the end of the MIMO designation. A 3×3:2 MIMO device has 3 transmitters, 3 receivers, and can support two unique spatial streams. Since not all devices in an environment may support the same amount of spatial streams, capabilities are advertised and the lowest common denominator is negotiated prior to transmitting data.

MAC Layer Efficiency

Additional improvements with 802.11n include block acknowledgement. In traditional 802.11 networks each frame of data transmitted must be acknowledged by the receiver. If no acknowledgement is received it is assumed that the receiver did not get the frame and it must be resent. Acknowledging each frames wastes communication time. With 802.11n  all the data frames can be transmitted in one burst, and only one acknowledgement is expected from the receiver. This is more efficient and helps increase throughput.

With 802.11 as OFDM symbols are transmitted they can take different paths to the receiver. If the two symbols arive two close together they can actually cause interference with each other, this is known as intersymbol interference (ISI). The 802.11 standard requires a guard interval of 800 nanoseconds between transmissions to alleviate this problem. With 802.11n devices you can configure this interval to 400 nanoseconds. Doing so will increase throughput since less time is wasted in the guard interval but it does put you at a greater risk of data corruption.

Transmit Beamforming

As data is transmitted across the multiple radio chains of a MIMO device, they will ultimately take separate paths to the receiver. To help ensure that the data arrives at the receive in the same relative time frame transmit beamforming (TxBF) is used. Transmit beamforming adjusts the phase of each signal as it leaves so that as it travels across the free space they will arrive at relatively the same time. The receiver sends back TxBF data as feedback so that the transmitter can constantly keep track of the required adjustments and send focused transmissions to each receiver dynamically.

Maximal-Ratio Combining

If you’re familiar with digital photography, you may be familiar with the concept of HDR, or High Dynamic Range. With HDR, multiple images are combined to provide a single image with the best contrast. Maximal-Ratio Combining (MRC) does something very similar with RF signals. It takes multiple received copies of a signal and combines them to provide one signal with improved Signal to Noise Ration and receiver sensitivity.

OFDM Deep Dive

With DSSS we spread the chips of a single data stream into one wide 22 MHz channel, and because of the constant chip rate of 11 MHz we are restricted to 11 Mbps of data throughput. On the other hand, Orthogonal Frequency-Division Multiplexing (OFDM) sends data bits in parallel over multiple frequencies , all contained within a single 20 MHz channel.  Each channel is divided into 64 sub-carriers (hence the Frequency-Division) which are spaced 312.5 kHz apart. There are 3 different types of sub-carriers:

  • Guard – 12 sub-carriers which are used to separate each channel and help receivers lock onto a channel. These actually aren’t transmitted but stay silent as spacing.
  • Pilot – 4 sub-carriers which are equally spaced and always transmitted to help receivers determine the noise state of the channel.
  • Data – 48 sub-carriers which are devoted to carrying data.

Since OFDM is transmitting data in parallel it is able to get high aggregate throughput through its relatively low throughput sub-carriers. Since the data is also sent in parallel we can also modify how much of it needs to be unique or repeated data for error prevention. The coding schemes in OFDM are named using fractions to identify the ratio of new bits to repeated bits (coder ratio); BPSK 1/2 indicates that one half of the bits are new and the other half repeated. BPSK 3/4 therefore indicates that three-fourths of the bits are new and only one fourth are repeated.

At the lower speeds, BPSK modulation can be used with two different coder ratios. OFDM and BPSK 1/2 results in a 6 Mbps throughput and with BPSK 3/4 achieves 9 Mbps throughput. If we combine OFDM with QPSK 1/2 we can achieve 12 Mbps and QPSK 3/4 can achieve 18 Mbps. If you recall the DSSS post we introduced QPSK and the fact that it uses 2 binary bits to give four possible phase shifts. Therefore for us to break through 18 Mbps we would need a additional modulations options.

Quadrature Amplitude Modulation (QAM) combines QPSK phase shifting with multiple amplitude level to give an even greater number of modulation options. As an example 16-QAM uses 2 bits for the QPSK modulation and an additional 2 bits for the amplitude for a total of 4 bits used for modulation changes. 4 binary bits would give use 16 unique modulation options (hence the name). The coder ratios still apply when we move to QAM so the names still carry a fractional prefix indicating the ratio. The current OFDM supposed modulation options include:

  • OFDM QPSK 1/2 – 12 Mbps
  • OFDM QPSK 3/4 – 18 Mbps
  • OFDM 16-QAM 1/2 – 24 Mbps
  • OFDM 16-QAM 3/4 – 36 Mbps
  • OFDM 64-QAM 2/3 – 48 Mbps
  • OFDM 64-QAM 3/4 – 54 Mbps
  • OFDM 256-QAM 3/4 – 78 Mbps
  • OFDM 256-QAM 5/6 – 86 Mbps

The IEEE 802.11g amendment was introduced in 2003 and is also commonly called Extended Rate PHY (ERP) or ERP-OFDM. ERP is just another name for 802.11g in the 2.4 GHz band. Since 802.11g was based on OFDM as opposed to DSSS in the previous standard devices cannot directly understand each other’s RF signals. 802.11g was intended to be backwards compatible with legacy 802.11b devices by downgrading and using DSSS, however the reverse is not true. To allow both OFDM and DSSS devices to coexist a protection mechanism was included. When using 802.11g Protection Mode, before a device transmits it will send a warning message with DSSS before transmitting its data with OFDM. Protection mode is enforced automatically if an 802.11b devices is detected on the WLAN, and once it leave the network it is lifted. Since the protection mode adds the additional DSSS warning messages it greatly reduces network throughput.

So we’ve already covered 802.11b and 802.11g why are we just now circling around to 802.11a (yes they do go in order). Actually almost as soon as 802.11 was ratified the need was recognized to limit interference. 802.11a was introduced in 1999, earlier in the same year at 802.11b however since migrating from 2.4 GHz to 5 GHz required new hardware it was never widely adopted. IEEE 802.11a restricts devices to use OFDM only and is based on channels that are 20 MHz wide. Since it only supported OFDM it was not backwards compatible with any devices and depending on the modulation scheme any of the supported data rates were available.

DSSS Deep Dive

1 Mbps DSSS

To achieve the 1 Mbps throughput with DSSS, each bit of a data was encoded into a sequence of 11 bits. This is called the Barker 11 Code. In the Barker code, a 0 data bit is always represented as (10110111000) and a 1 data bit is represented as (01001000111). With these 11 bit chips, up to 9 of the bits can be lost before the original data bit cannot be restored. To transmit each chip Differential Binary Phase Shift Keying (DBPSK) modulation is used. Binary being the key word in that scheme since 1 or 0 gives us two options. With DBPSK the carrier signal is shifted or rotated depending on the bit. A 0 bit would result in no change to the carrier signal, and 1 bit would rotate or shift the signal 180 so that it was suddenly upside down. DSSS always uses a chipping rate of 11 million chips per second, so when each symbol (original bit) contains 11 chips, we get a transmitted data rate of 1 Mbps.

2 Mbps DSSS

To double our initial throughput we keep the original 11 bit Barker code but instead of this time we modulate the symbols using Differential Quadrature Phase Shift Keying (DQPSK). Quadrature (4) being the key word in this scheme. With DQPSK two chips are modulated at a time, and since we have 2 binary bits that gives us 4 possible options:

  • 00 – The phase is not changed
  • 01 – The phase is rotated 90 degrees
  • 11 – The phase is rotated 180 degrees
  • 10 – The phase is rotated 270 degrees

Since the data bits are modulated in pairs we are able to transmit twice as much data in the same amount of time compared to DBPSK, which gives DQPSK twice the throughput with 2 Mbps.

As we briefly mentioned in our initial modulation post, IEEE 802.11-1997 was the first standard. It included FHSS and DSSS using either DBPSK or DQPSK in the 2.4 GHz band. The 802.11-1997 standard only supported Barker coding for the maximum throughput of 2 Mbps.

5.5 Mbps DSSS

To increase our throughput Complementary Code Keying (CCK) was introduced to replace the Barker code. CCK takes 4 bits of original data at a time to create a unique 6 chip symbol. After the original bit is encoded 2 more chips are added to the symbol to indicate the phase orientation per DQPSK, making a total symbol of 8 chips. So Barker coding gave us a 1:11 coding ratio CCK gives us a 4:8. Given the steady chipping rate of 11 MHz with DSSS and each symbol containing 8 chips, we get a symbol rate of 1.375 MHz (11 MHz / 8). Since each symbol is based on 4 original data bits we get an effective data rate of 5.5 Mbps (1.375 MHz * 4).

11 Mbps DSSS

By making an adjustment to the encoder, we can take 8 original data bits to create the 8 chip symbols. By doubling the the amount of original data in the chip we double the throughput rate. Since we’re still using 8 chip symbols and the constant 11 MHz chipping rate we still have a symbol rate  of 1.375 MHz, but with 8 data bits in each symbol we can now reach 11 Mbps (1.375 MHz * 8). Increasing the number of data bits in symbol means we lose some of the resiliency to recover information. While we’ve increased throughput we are more sensitive interference and therefore require a stronger and less-noisy signal.

IEEE 802.11b was introduced in 1999 and standardize the use of CCK supporting a maximum throughput of 11 Mbps. Since 802.11b was based on DSSS and the 2.4 GHz band it was also backwards compatible with the original standard and devices could select their speed by simple changing the modulation or coding schemes.

RF Modulation and Standards

So we’ve talked about the frequency bands and transmit power, but how are these things utilized to actually carry our network data? Since computers communicate in binary bits, we have to be able to differentiate a 1 or a 0 on an RF signal.  Since RF isn’t a closed circuit we can’t use on/off to signal 1 or 0, the only thing we can do is modify the RF signal in some way to make it slightly different. Modifying the RF signal to indicate the data it is carrying is known as modulation. Given the physical properties of an RF signal modulation can only alter a few attributes of the signal. We can modify the frequency, but only slightly above or below the carrier frequency. We can modify the phase of the signal, which is the timing relative to the start of the cycle. Or we can modify amplitude which is the strength or height of the signal.

Since our wireless networks require sending data at high bit rates (fast), we require more bandwidth to modulate this data. This additional bandwidth is distributed across a range of frequencies as opposed to using a single carrier signal. We call this distribution Spread Spectrum since we are spreading the signal across multiple frequencies. There are 3 primary categories of spread spectrum used for wireless data networks: Frequency-Hopping Spread Spectrum (FHSS), Direct-Sequence Spread Spectrum (DSSS), and Orthogonal Frequency-Division Multiplexing (OFDM). We will expand on DSSS and OFDM in future posts.

I also want to take a moment to introduce the wireless standards. The first standards bodies we need to be concerned with are the ITU-R which is set up by the United Nations to manage RF spectrum globally. In the United States the Federal Communications Commission (FCC) regulates frequencies, RF channels, and transmission power. A similar body called the European Telecommunications Standards Institute (ETSI) manages the same things in the European region. On top of the RF standards we have the familiar IEEE which manages a majority of our computer standards. IEEE 802 standards deal all deal with local area and metro area networks and specifically IEEE 802.11 is responsible for wireless networks. As we work through the different RF transmitting schemes I will include a mention on which 802.11 standard introduced or maintained the technology.

The initial wireless network standards utilizing an idea call frequency hopping was used to avoid interference with other devices in the ISM band. In a frequency hopping system the transmitter and receiver have to be synchronized so they know which frequency they are supposed to be on at any given time. To accomplish they they switch between channels at regular intervals. To avoid interference small channels are used so that if interference does occur it will not be a large impact on the data being transmitted. FHSS utilized 1-MHz channels spread across the entire band. These smaller sized channels meant that only so much data could be transmitted at a time and this limited bandwidth to 1 or 2 Mbps. Also multiple transmitters (access points) in an area would eventually collide with each other on the same channels. For these reasons FHSS was fairly quickly replaced with DSSS.

Instead of using many small channels, DSSS utilized a smaller number of wider channels. With DSSS each channel is 22-MHz wide with a maximum supported throughput of 11-Mbps. DSSS was designated to be used in the 2.4GHz band. As noted in previous posts this is where we run into the problem of overlapping channels, since the ISM band and it’s 5 MHz channels existed before the wireless standard which dictated the 22-MHz wide channels. The non-overlapping channels available in the US are 1, 6, and 11. As the name indicates, DSSS transmits data in a direct sequence, or a serial stream. Instead of frequency hopping to avoid interference DSSS relies on a few methods to try an alleviate any interference problems:

  • Scrambling – Instead of transmitting long sequences of 1s or 0s (think in binary), the data is first sent through a scrambler to generate a randomized sequence of 0s or 1s.
  • Coding – Each bit of data is converted into multiple bits using special patterns that help protect against errors. Think of using the phonetic alphabet for radio transmissions. Instead of saying each letter individually we use a word to describe the letter. ‘A’ becomes ‘alpha’, ‘B’ becomes ‘bravo’, ‘C’ becomes ‘charlie’, and so on. This requires more data to transmit the original data however it helps eliminate errors and the need for re-transmission. Error correction is more costly than error prevention. Each of the newly coded bits is called a Chip, and the complete group of chips representing a data bit is called a Symbol. DSSS utilizes two encoding techniques, either Barker Codes or Complementary Code Keying (CCK).
  • Interleaving – The encoded data is then spread out into separate blocks so that temporary interference would only affect a smaller number of blocks.
  • Modulation – Finally the bits in each symbol are used to modulate the phase of the carrier signal.

The original 802.11 standard was ratified in 1997. It originally included two main transmission types FHSS or DHSS for use only in the 2.4 GHz band.

RF Power – dB vs dBm vs dBi vs dBd

The dBm

The dBi

The dBd

Comparing RF Power

Power Change dB Value
= 0 dB
x 2 +3 dB
/ 2 -3 dB
x 10 + 10 dB
/ 10 -10 dB

5 x 2 = 10
10 x 10 = 100

  1. 3mW vs 12mW
  2. 5mW vs 50mW
  3. 5mW vs 200mW
  4. 60mW vs 3mW
  5. 500mW vs 5mW

RF Channels and Bandwidth

In my previous post I outlined the frequency bands used for wireless LANs and briefly touched on the channels within those bands. I’m going to delve into those channels a little more in this post.

We’ve already established that a frequency band is a range of frequencies which are further divided into specific channels. Those channels are defined by standards bodies such as the FCC in the USA or the ITU internationally.

Channels within a band are defined based on a center frequency. Since real life is messy, we can’t limit an RF signal to just the center frequency. It spills over on each side of the center frequency to some degree, we call this sideband. The range of the spillage above and below the center frequency is what we call the signal bandwidth. Technically the bandwidth is the difference between the upper and lower cutoff frequencies. Another way to say it is that the signal bandwidth is the full range required to transmit on a specific RF frequency. These are defined in the 802.11 standards as the channel width.

As we said earlier, life is messy; but we do our best to clean it up. One of the tools we use to clean up a channel is a spectral mask. Spectral masks are overlays of what the channel should look like. Anything frequencies outside of the spectral mask are attenuated to help limit channel interference.

The problem that we sometimes run into and especially with the 2.4 GHz band is that the RF channel increments were defined prior to its adoption for communication use. In the 2.4 GHz (ISM) band the channels, or the center frequency, increment every 5 MHz. However in the 802.11 standards we have defined 11 MHz on each side of the center frequency which combined give the channel width of 22 MHz. Cramming something 22 MHz wide into something spaced out every 5 MHz quite obviously leads to channel overlap.

Hopefully this gives you some visualization on RF signal bandwidth and helps explain the discrepancy between the total number of channels in the 2.4 GHz band vs number of usable channels.

All images are my own and were crudely made using MS Visio.


A benign tumor which usually occurs in young children or infants and is composed of newly formed blood vessels. It results from improperly formed angioblastic tissue in the fetus.


General hospital

Real-Time Location System Tracks Staff, Patients, and Equipment, Reducing Costs, Improving Infection Control and Room Turnaround, and Generating High Satisfaction 02/27/14

Hospitals use a real-time location system to track employees, patients, and/or major pieces of equipment, leading to lower equipment costs, better infection control processes, faster room turnaround, and high levels of patient, physician, and staff satisfaction.

California Law Enhances Access to Affordable Care by Limiting Amount Hospitals Can Collect From Low-Income Uninsured and Underinsured Patients 01/30/14

California legislation enhances access to affordable care by limiting the amount hospitals can collect from low- and moderate-income patients who are uninsured or lack adequate coverage and hence face high out-of-pocket medical expenses.

Comprehensive Program To Improve Discharge Process Reduces Readmissions 11/01/13

Project BOOST (Better Outcomes by Optimizing Safe Transitions) provides hospitals a comprehensive set of interventions to improve the care transition process after discharge, leading to a significant reduction in readmissions.

Voluntary Citywide Initiative To Support Mothers Who Choose To Breastfeed Attracts Many Hospitals, Wins Support of Medical Community 05/23/13

A city health department encourages public and private maternity hospitals to voluntarily adopt various policies to support new mothers who choose to breastfeed exclusively. The program has attracted many participating hospitals, won broad support within the medical community, and increased the proportion of new mothers who breastfeed exclusively during their hospital stay.

Hospital–Retail Pharmacy Partnership Provides Inhospital and Postdischarge Support to At-Risk Patients, Leading to Fewer Readmissions and High Patient Satisfaction 05/22/13

A partnership between a hospital and retail pharmacy company provides inhospital and postdischarge support to patients at high risk of readmission, leading to fewer readmissions and high levels of patient satisfaction.

Statewide, All-Payer Financial Incentives Significantly Reduce Hospital-Acquired Conditions in Maryland Hospitals 02/28/13

Financial incentives used by all Maryland public and private payers significantly reduce hospital-acquired conditions in hospitals throughout the state.

Statewide, All-Payer Financial Incentives Tied to Process, Patient Experience, and Outcomes Measures Lead to Better and Less Variable Hospital Performance 02/26/13

A statewide, all-payer initiative creates financial incentives tied to hospital performance on process, patient experience, and outcomes measures, leading to better and less variable performance.

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Questions Of Confidence

Some readers have asked why, given my scornful discussions of the “confidence fairy” story about fiscal austerity (will that be my lasting contribution to economic discourse?), I’m willing to take seriously the idea that ECB rate hikes had a huge impact via expectations.

That’s a good question, but I do have answers.

First of all, the ECB story is about the bond market; the expansionary austerity story isn’t. Instead, to believe that fiscal contraction will lead to higher consumption and investment spending you have to believe that consumers and firms will make major changes in their current behavior based on perceptions about taxes and spending years in the future. And that’s just a lot less plausible. The likes of Pimco are out there trying to figure out the implications of ECB behavior, and investing accordingly; how many families do you know deciding on holiday purchases based on expectations of tax policy in 2014?

Second, the monetary story is a lot more concrete. The ECB’s readiness to raise rates despite low core inflation and high unemployment tells you a lot about the likelihood that it would choke off the modest rise in inflation needed to make the eurozone adjustment feasible. Do Cameron’s budget cuts convey any comparable information about future UK taxes and/or solvency? I don’t think so.

Finally, the whole euro situation is fraught with multiple equilibria and the risk of self-fulfilling panics — which means that there can sometimes be disproportionate responses in a way that doesn’t make sense when we’re talking about budget cuts.

So yes, expectations can matter; but some expectational arguments are more equal than others.


Date of Award

Winter 2017

Project Type

Program or Major

Chemical Engineering

Degree Name

Doctor of Philosophy

First Advisor

Harish Vashisth

Second Advisor

Russell T. Carr

Third Advisor

Kang Wu

I used molecular dynamics (MD) simulations as a primary tool to study folding and dynamics of signaling and regulatory proteins. Specifically, I have studied two classes of proteins: the first part of my thesis reports studies on peptides and receptors of the insulin family, and the second part reports on studies of regulatory proteins from the G-protein coupled receptor family. The first problem that I investigated was understanding the folding mechanism of the insulin B-chain and its mimetic peptide (S371) which were studied using enhanced sampling simulation methods. I validated our simulation approaches by predicting the known solution structure of the insulin B-chain helix and then applied them to study the folding of the mimetic peptide S371. Potentials of mean force (PMFs) along the reaction coordinate for each peptide are further resolved using the metadynamics method. I further proposed receptor-bound models of S371 that provide mechanistic explanations for competing binding properties of S371 and a tandem hormone-binding element of the receptor known as the C-terminal (CT) peptide. Next, I studied the all-atom structural models of peptides containing 51 residues from the transmembrane regions of IR and the type-1 insulin-like growth factor receptor (IGF1R) in a lipid membrane. In these models, the transmembrane regions of both receptors adopt helical conformations with kinks at Pro961 (IR) and Pro941 (IGF1R), but the C-terminal residues corresponding to the juxta-membrane region of each receptor adopt unfolded and flexible conformations in IR as opposed to a helix in IGF1R. I also observe that the N-terminal residues in IR form a kinked-helix sitting at the membrane-solvent interface, while homologous residues in IGF1R are unfolded and flexible. These conformational differences result in a larger tilt-angle of the membrane-embedded helix in IGF1R in comparison to IR to compensate for interactions with water molecules at the membrane-solvent interfaces. The metastable/stable states for the transmembrane domain of IR, observed in a lipid bilayer, are consistent with a known NMR structure of this domain determined in detergent micelles, and similar states in IGF1R are consistent with a previously reported model of the dimerized transmembrane domains of IGF1R. I further studied dimerization propensities of IR transmembrane domains using three different constructs in a lipid bilayer (isolated helices, ectodomain-anchored helices, and kinase-anchored helices). These studies revealed that the transmembrane domains can dimerize in isolation and in kinase-anchored forms, but not significantly in the ectodomain construct. The final studies in my thesis are focused on interplay of protein dynamics and small-molecule inhibition in a set of regulatory proteins known as the Regulators of G-protein Signaling (RGS) proteins. Thiadiazolidinone (TDZD) compounds have been shown to inhibit the protein-protein interaction between RGS and the alpha subunit of G-proteins by covalent modification of cysteine residues in RGS proteins. However, some of these cysteines in RGS proteins are not surface-exposed. I hypothesized that transient binding pockets expose cysteine residues differentially between different RGS isoforms. To explore this hypothesis, long time-scale classical MD simulations were used to probe the dynamics of three RGS proteins (RGS4, RGS8, and RGS19), and characterize flexibility in various helical motifs. The results from simulation studies were validated by hydrogen-deuterium exchange (HDX) studies, and revealed motions indicating solvent exposure of buried cysteine residues, thereby providing insights into inhibitor binding mechanisms. In addition, I used different published HDX models which have resulted in a comprehensive comparison of existing models. Furthermore, I developed the new HDX models with optimized parameters which had comparable accuracy and more computational efficiency compared to other models. Overall, my thesis has resulted in the development and applications of several state-of-the-art computational methods that have provided a detailed mechanistic understanding of peptide and small-molecule based inhibitors and their interactions with large proteins that are potentially useful in designing novel approaches to target protein-protein interactions.


Thu, Sep

Marine Imaging Technologies (MITech), a leader in developing state-of-the-art underwater optical imaging platforms, today introduced Pixel, the first Cinema Class remotely operated vehicle, or ROV. Pixel is a multi-camera underwater filming and exploration platform that will facilitate deep water and coastal storytelling unlike ever before, enabling storytellers to record cinema quality images while minimizing the associated hazards and costs.

Pixel, as well as other forthcoming ROVs in MITech’s Cinema Class line, simultaneously hosts multiple cameras with live video and control feeds. From Ultra Hi Def (UHD) and large format stills to stereoscopic and Virtual Reality, Pixel’s versatility broadens the choices for aquatic storytellers.

“Telling stories about underwater is always a challenge, but once you enter deeper water where diving becomes less feasible, there simply were no options for true cinema class filming,” says Evan Kovacs, founder of Marine Imaging Technologies. “To that end, the Pixel platform has been designed from the bottom up to accommodate not only the exciting cinema quality we’ve all become accustomed to, but also to lessen the burden on the filming budget. We’re thrilled with Pixel and think it will be a game-changer in the industry.”

Before Pixel, underwater storytellers managed the filming process using submersibles or ROVs with the capabilities to accommodate a moderate camera and lighting system, which in turn required extensive surface support. Pixel was conceived as UHD was becoming mainstream and is designed to fully utilizevUHD cameras and subsequent cinematic advances. In addition to the multitude of camera options, Pixel is designed with a lighting system capable of over 100,000 lumens of articulated lighting and a precision thruster configuration to perform smooth cinematic movements. Pixel’s controls, in the hands of pilots who have a real world understanding of camera moves and working in a deep water environment, will make for a unique directorial experience and enable exploration and cinema filming in a way that has never been possible from a vehicle of this compact size.

For cameras operators, Pixel will be intuitively familiar, since the system was designed to incorporate the controls of industry standard remote lenses and camera control systems. Additionally, the MITech design team added portability to the list of requirements, designing Pixel to break down to fit into industry standard pelican cases, allowing for airline transport to locales where big containers are not possible or are cost prohibitive.

“As a veteran deep water cinematographer and storyteller, I have often lamented that we had to strap cameras to vehicles that had absolutely no aesthetic, nor hydrodynamic characteristics. Considering we are living in a time where multimedia has been absorbed into the foundation of our education and entertainment culture, we knew this needed to change,” says Kovacs. “Our aim was to make Pixel move well in the water, have the best cameras and look like it actually was designed to be our literal eyes beneath the sea. We want Pixel to become an intimate part of the constantly evolving and changing dynamic of our underwater world.”


Furious passengers at Dublin Airport have slammed delays as a "complete joke" while trying to get through passport control.

A flurry of social media posts on Twitter reported huge queues at Terminal 1 late on Sunday night, with many claiming they were still waiting over an hour after their flight landed, Dublin Live report .

Twitter user @jimf19731 called the delays "ridiculous" and posted: "1 hours queues in T1 at passport control Dublin Airport #ridiculous #onlyinireland."

It has been claimed online that the backlog is due to low staff numbers at passport control.

One furious passenger called the queues a "shambles", while another responded: "I'm 20 yards behind you in same queue.

"How difficult is it to count the number of passengers due in and open appropriate number of desks?"

Another irate passenger said he missed the last bus to the city centre due to the delays.

The Irish Naturalisation and Immigration Service (INIS) control immigration through Terminal 1 and have been reached out to for comment.


Papers by Keyword: Microcarriers

Paper TitlePage

Authors: J. Feng, M. Chong, J. Chan, Z.Y. Zhang, S.H. Teoh, Eng San Thian
Abstract: The current available microcarriers were mainly targeted towards pharmaceutical industries, and might not be suitable for therapeutic implantation. As such, apatite-based microcarriers intended for bone tissue engineering applications would be featured here. Hydroxyapatite-Alginate (HA-Alg) suspension was extruded drop-wise into a calcium chloride (CaCl2) crosslinking solution. The HA-Alg microcarriers were then sintered to form microcarriers of uniform size. The physicochemical properties were analysed by scanning electron microscopy (SEM), X-ray diffractometery (XRD), and fourier transform infrared (FTIR) spectrophotometry. Cell viability on these microcarriers was evaluated using human fetal mesenchymal stem cells (hfMSCs). SEM images revealed that sintered apatite-based microcarriers exhibited a rough surface topology with interconnected pores. XRD results showed that these microcarriers remained phase pure since no other secondary calcium phosphate phases were detected. FTIR analysis indicated several sharp phosphate bands coupled with a hydroxyl band (all belonging to HA). Live/dead staining showed that hfMSCs remained viable after 14 days of culture, and cells have spread and covered the surfaces of the microcarriers. Certainly, these cell-loaded microcarriers could be potentially used in bone implant science.
Authors: Ju Hee Ryu, Byoung Soo Kim
Abstract: Previously, we have developed a novel method for suspension culture of anchoragedependent animal cells using biodegradable polymer nanospheres. In this study, we compared the polymer nanosphere culture method to dextran microcarrier culture method, which is a conventional suspension culture method. Most of human dermal fibroblasts (91 ± 5 %) cultured with polymer nanospheres formed aggregates on day 2. Most of cells (92 ± 7 %) attached onto microcarriers by 4 h. Microcarrier culture method had a lower apoptotic activity (3.4 folds on day 4), compared to the nanosphere culture. The microcarrier culture method had a higher cell growth (2.4-fold versus 1.7- fold growth on day 4) than the nanosphere culture. Although the polymer nanosphere culture method did not yield better outcomes than the microcarrier culture, the polymer nanosphere culture method may offer advantages over the microcarrier culture method with respect to cell protection from the shear stress during agitation at high speed and cell transplantation without enzyme digestion process to harvest cultured cells.
Authors: Lei Ye, Shu Ding, Yuan Lu Cui, Qiang Song Wang, Ye Zhang
Abstract: This article presents the optimization of process parameters in chitosan-gelatin composite microcarriers preparation based on multi-index test breakdown formula evaluation combined with orthogonal array. In this study, the concentration of crosslinker solution, the concentration of water phase and stirring speed were considered as controllable factors, and three levels for each of these factors were selected, in an L9 orthogonal array. The optimal levels of the process parameters were determined through the range analysis and the relative importance among the process parameters were identified through analysis of variance. According to the evaluations of particle size, morphological analysis, compressibility, and equilibrium swelling from the nine different sets, the optimum combinations for microcarriers preparation were showed as: the concentration of crosslinker solution:0.5% (wt/v), the concentration of water phase:5% (wt/v) and stirring speed:240 rpm.
Authors: Gabriela A. Silva, Olga P. Coutinho, Rui L. Reis
Abstract: In the present work we describe the synthesis of starch-based/BG 45S5 particles and their in vitro bioactivity behaviour by means of immersion in a simulated body fluid. The composite particles have shown to form a layer of Ca-P at their surface, whose nature was confirmed by chemical and morphological analysis. In order to evaluate the ability of these particles to be used as carriers for cell culture, undifferentiated rat cells were selected and parameters like cell adhesion, proliferation and expression of osteoblastic markers, were evaluated. The starch-based micro-particles have shown to support cellular activity, allowing cells to attach, proliferate and express specific markers while cultured in the particles surface. The final goal is to be able to use these particles as carriers for cells and simultaneously as in-situ forming constructs for tissue engineering and regenerative medicine applications.
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Wi-Lan Inc. v. Sharp Electronics Corporation

United States District Court, D. Delaware

April 27, 2018

WI-LAN INC., Plaintiff,
VIZIO, INC., Defendant.

          Brian E. Farnan and Michael J. Farnan, FARNAN LLP, Wilmington, DE, Monte M. Bond, Jeffrey R. Bragalone, Patrick J. Conroy, Terry Saad, and James R. Perkins, BRAGALONE CONROY P.C, Dallas, TX, Attorneys for Plaintiff.

          Jack B. Blumenfeld and Stephen J. Kraftschik, MORRIS, NICHOLS, ARSHT & TUNNELL LLP, Wilmington, DE, Gianni Cutri and Joel Merkin, KIRKLAND & ELLIS LLP, Chicago, DL, Michael W. De Vries, KIRKLAND & ELLIS LLP, Los Angeles, CA, Adam R. Alper and James Beard, KIRKLAND & ELLIS LLP, San Francisco, CA, Jared Barcenas, KIRKLAND & ELLIS LLP, New York, NY, Attorneys for Sharp Electronics Corporation.

          Pilar Gabrielle Kraman, YOUNG, CONAWAY, STARGATT & TAYLOR, LLP, Wilmington, DE, Adrian M. Pruetz and Rex Hwang, GLASER WEIL FINK HOWARD AVCHEN & SHAPIRO LLP, Los Angeles, CA, Attorneys for Vizio, Inc.

         Plaintiff Wi-LAN Inc. ("Plaintiff") brought this patent infringement suit against Defendants Sharp Corporation, Sharp Electronics Corporation, and Vizio, Inc. ("Defendants"), alleging that Defendants infringe Plaintiffs U.S. Patent Nos. 6, 359, 654 (the "'654 patent") and 6, 490, 250 (the "'250 patent"). (See generally D.I. 15)[1] The '654 patent generally relates to methods to display interlaced video on non-interlaced monitors. ('654 patent, Abstract) The '250 patent generally relates to an integrated multimedia encoding system. ('250 patent, Abstract)

         Presently before the Court is the issue of claim construction. The parties submitted technology tutorials (see D.I. 252, 256), objections to such technology tutorials (see D.I. 267, 270), claim construction briefs (see D.I. 253, 254, 266, 269), and expert declarations (see D.I. 253-1, 255-3, 255-4, 266-1). The Court held a claim construction hearing on February 26, 2018, at which both sides presented oral argument. (See D.L 272 ("Tr."))

         The ultimate question of the proper construction of a patent is a question of law. See Teva Pharm. USA, Inc. v. Sandoz, Inc., 135 S.Ct. 831, 837 (2015) (citing Markman v. Westview Instruments, Inc., 517 U.S. 370, 388-91 (1996)). "It is a bedrock principle of patent law that the claims of a patent define the invention to which the patentee is entitled the right to exclude." Phillips v. AWH Corp., 415 F.3d 1303, 1312 (Fed. Cir. 2005) (internal quotation marks omitted).

         "[T]here is no magic formula or catechism for conducting claim construction." Id. at 1324. Instead, the Court is free to attach the appropriate weight to appropriate sources "in light of the statutes and policies that inform patent law." Id.

         "[T]he words of a claim are generally given their ordinary and customary meaning ... [which is] the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention, i.e., as of the effective filing date of the patent application." Id. at 1312-13 (internal citations and quotation marks omitted). "[T]he ordinary meaning of a claim term is its meaning to the ordinary artisan after reading the entire patent." Id. at 1321 (internal quotation marks omitted). The patent specification "is always highly relevant to the claim construction analysis. Usually, it is dispositive; it is the single best guide to the meaning of a disputed term." Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).

         While "the claims themselves provide substantial guidance as to the meaning of particular claim terms, " the context of the surrounding words of the claim also must be considered. Phillips, 415 F.3d at 1314. Furthermore, "[o]ther claims of the patent in question, both asserted and unasserted, can also be valuable sources of enlightenment... [b]ecause claim terms are normally used consistently throughout the patent." Id. (internal citation omitted).

         It is likewise true that "[differences among claims can also be a useful guide-----For example, the presence of a dependent claim that adds a particular limitation gives rise to a presumption that the limitation in question is not present in the independent claim." Id. at 1314-15 (internal citation omitted). This "presumption is especially strong when the limitation in dispute is the only meaningful difference between an independent and dependent claim, and one party is urging that the limitation in the dependent claim should be read into the independent claim." SunRace Roots Enter. Co., Ltd. v. SRAM Corp., 336 F.3d 1298, 1303 (Fed. Cir. 2003).

         It is also possible that "the specification may reveal a special definition given to a claim term by the patentee that differs from the meaning it would otherwise possess. In such cases, the inventor's lexicography governs." Phillips, 415 F.3d at 1316. It bears emphasis that "[e]ven when the specification describes only a single embodiment, the claims of the patent will not be read restrictively unless the patentee has demonstrated a clear intention to limit the claim scope using words or expressions of manifest exclusion or restriction." Hill-Rom Servs., Inc. v. Stryker Corp., 755 F.3d 1367, 1372 (Fed. Cir. 2014) (quoting Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 906 (Fed. Cir. 2004)) (internal quotation marks omitted).

         In addition to the specification, a court "should also consider the patent's prosecution history, if it is in evidence." Markman v. Westview Instruments, Inc., 52 F.3d 967, 980 (Fed. Cir. 1995), aff'd, 517 U.S. 370 (1996). The prosecution history, which is "intrinsic evidence, " "consists of the complete record of the proceedings before the PTO [Patent and Trademark Office] and includes the prior art cited during the examination of the patent." Phillips, 415 F.3d at 1317. "[T]he prosecution history can often inform the meaning of the claim language by demonstrating how the inventor understood the invention and whether the inventor limited the invention in the course of prosecution, making the claim scope narrower than it would otherwise be." Id.

         In some cases, "the district court will need to look beyond the patent's intrinsic evidence and to consult extrinsic evidence in order to understand, for example, the background science or the meaning of a term in the relevant art during the relevant time period." Teva, 135 S.Ct. at 841. Extrinsic evidence "consists of all evidence external to the patent and prosecution history, including expert and inventor testimony, dictionaries, and learned treatises." Markman, 52 F.3d at 980. For instance, technical dictionaries can assist the court in determining the meaning of a term to those of skill in the relevant art because such dictionaries "endeavor to collect the accepted meanings of terms used in various fields of science and technology." Phillips, 415 F.3d at 1318. In addition, expert testimony can be useful "to ensure that the court's understanding of the technical aspects of the patent is consistent with that of a person of skill in the art, or to establish that a particular term in the patent or the prior art has a particular meaning in the pertinent field." Id. Nonetheless, courts must not lose sight of the fact that "expert reports and testimony [are] generated at the time of and for the purpose of litigation and thus can suffer from bias that is not present in intrinsic evidence." Id. Furthermore, "statements made by a patent owner during an IPR [inter partes review] proceeding ... can be considered for claim construction." Aylus Networks, Inc. v. Apple Inc., 856 F.3d 1353, 1362 (Fed. Cir. 2017). Overall, while extrinsic evidence "may be useful" to the court, it is "less reliable" than intrinsic evidence, and its consideration "is unlikely to result in a reliable interpretation of patent claim scope unless considered in the context of the intrinsic evidence." Id. at 1318-19. Where the intrinsic record unambiguously describes the scope of the patented invention, reliance on any extrinsic evidence is improper. See Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1308 (Fed. Cir. 1999) (citing Vitronics, 90 F.3d at 1583).

         Finally, "[t]he construction that stays true to the claim language and most naturally aligns with the patent's description of the invention will be, in the end, the correct construction." Renishaw PLC v. Marposs Societa' per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998). It follows that "a claim interpretation that would exclude the inventor's device is rarely the correct interpretation." Osram GmbH v. Int'l Trade Comm'n 505 F.3d 1351, 1358 (Fed. Cir. 2007) (quoting Modine Mfg. Co. v. U.S. Int'l Trade Comm'n, 75 F.3d 1545, 1550 (Fed. Cir. 1996)).

         A. '654 Patent

         1. "A method for displaying interlaced video data on a non-interlaced monitor, the interlaced video data comprising a plurality of paired fields, each pair of fields being vertically offset relative to each other by one-half of a field line spacing distance, each field comprising a plurality of lines of video data"[2]

Plaintiff Preamble is not limiting Plain and ordinary meaning No construction necessary

Defendants Preamble is limiting

Court Preamble is limiting

         The parties dispute whether the preamble of claim 1 is limiting. "[A] preamble limits the invention if it recites essential structure or steps, or if it is necessary to give life, meaning, and vitality to the claim." Catalina Marketing Int'l, Inc. v., Inc., 289 F.3d 801, 808 (Fed. Cir. 2002) (internal quotation marks omitted). In other words, "when the preamble is essential to understand limitations or terms in the claim body, the preamble limits claim scope." Id. Moreover, "[w]hen limitations in the body of the claim rely upon and derive antecedent basis from the preamble, then the preamble may act as a necessary component of the claimed invention." Pacing Techs., LLC v. Garmin Int'l, Inc., 778 F.3d 1021, 1024 (Fed. Cir. 2015) (internal quotation marks omitted). "Conversely, a preamble is not limiting where a patentee defines a structurally complete invention in the claim body and uses the preamble only to state a purpose or intended use for the invention." Catalina Marketing, 289 F.3d at 808 (internal quotation marks omitted).

         Plaintiff argues that the preamble is not limiting, because it "does not contain any steps, " but rather "describes an intended use of the claimed process" - displaying interlaced video data on a non-interlaced monitor - and the '"features that necessarily exist' in interlaced video data." (D.I. 254 at 1-2; see also D.I. 266 at 1 (quoting Schumer v. Lab. Computer Sys., Inc., 308 F.3d 1304, 1310 (Fed. Cir. 2002))) Defendants argue that the preamble is limiting, because it "recites the framework essential to understand the remainder of the claim and provides antecedent basis for numerous elements." (D.I. 269 at 2)

         The Court concludes that the preamble is limiting because it is essential to understanding terms in the remainder of the claim. For example, step (c) of the claim requires "correct[ing] the vertical offset;" without the preamble, a person of ordinary skill in the art ("POSA" or "POSITA") would not know that the vertical offset is precisely "one-half of a field line spacing distance." ('654 patent, cl. 1)

         2. "respective buffers"[3]

Plaintiff Plain and ordinary meaning No construction necessary Plain and ordinary meaning is "a first and second memory space"

Defendants "separate buffers for the first field and the second field"

Court "separate buffers for the first field and the second field"

         Both sides agree that the term "respective buffers" requires that there be separate buffers for each field. (See Tr. at 24, 25, 38, 40) But Plaintiff argues that the claims do not require two separate buffers each with separate memory spaces; rather, the claims permit one buffer that has sufficient memory space to store both fields while "maintain[ing] separateness of the fields." (Tr. at 29) Defendants argue that the patent teaches there must be two distinct buffers for each of the two fields in the pair of fields. (See D.I. 253 at 3; Tr. at 27-28)

         The Court agrees with Defendants. In describing the background of the technology, the specification notes that the prior art method of "[d]einterlacing by interleaving two fields into a single buffer... gives very objectionable results when viewing video with rapid horizontal action." ('654 patent at 1:47-53) This suggests that a single buffer, despite having sufficient memory space to store both fields separately without overlap, is not covered by the patent. The patent further provides:

[T]he present invention ... capture[s] the two fields into separate buffers, one for the odd field and one for the even field. When one of the fields has been captured into the buffer, the buffer is displayed, scaled to the requested dimensions on the monitor using some scaling hardware or software...That image is displayed until the next field is captured into another buffer, and then the subsequent image is displayed until the third field is captured into either the original first buffer, or into another (third) buffer. The multiple buffering is to ensure that a video buffer is not being updated while it is being displayed, to avoid ''tearing"....

(Id. at 4:43-60 (emphasis added)) Moreover, the asserted claims of the '654 patent specify "respective buffets" - that is, plural buffers. A POSA would understand that the patent claims completely separate buffers, rather than just separate memory spaces in a single buffer, in order to practice the claimed method.

         3. "scaling"[4]

Plaintiff Plain and ordinary meaning No construction necessary Plain and ordinary meaning is "changing by a constant factor the number of lines and/or pixels in an image"

Defendants "changing the vertical resolution of the video signal by a constant factor"[5]

Court "changing the vertical resolution by changing by a constant factor the number of lines and/or pixels in a field"

         Step (b) of claim 1 requires "scaling each of the first field and second field of each pair of fields to fill vertical resolution of the non-interlaced monitor." ('654 patent, cl. 1) While the parties agree that scaling involves changing something by a constant factor, they disagree as to what may be changed. (See D.I. 254 at 3; D.I. 269 at 4)

         Plaintiff argues that "[t]he term 'scaling' is used throughout the specification in its broad sense to describe various scaling methods" - line-by-line, pixel-by-pixel, vertically, and horizontally - "and is not limited to vertical scaling of lines." (D.I. 254 at 3; see also Tr. at 45) Plaintiff further argues that "there is no lexicography that would limit scaling to any one particular type of scaling, " nor is there anything in the patent 'that would rise to the level of a disavowal of any type of scaling." (Tr. at 44) Defendants counter that the '654 patent "universally refers to scaling in the context of adding new lines" and does not contemplate scaling solely by changing the number of pixels. (D.I. 253 at 5) While Defendants agree that scaling generally can be accomplished by just adding pixels and widening the horizontal resolution, in Defendants' view such scaling would not practice claim limitation (b), which requires "scaling... to fill vertical resolution of the non-interlaced monitor." (Tr. at 52; see also '654 patent, cl. 1)[6] Defendants are also concerned that Plaintiffs construction would improperly permit Plaintiff to contend that there is no requirement that the vertical resolution be changed, as long as it is filled. (See Tr. at 57) While Plaintiff conceded that simply adding pixels to widen the resolution horizontally would be "scaling" but would not meet the rest of the claim limitation - because it is not scaling to fill vertical resolution - Plaintiff also indicated that performing horizontal scaling would meet the claim limitation as long as it filled the vertical resolution. (See Id. at 56-57) Separately, Defendants further argue that Plaintiffs construction is incorrect because "the claimed scaling occurs on fields, not images, of video data." (D.I. 253 at 4) (emphasis omitted)

         While the Court recognizes there may be various types of scaling in general, the Court agrees with Defendants that all references to scaling in the specification of the '654 patent refer to vertical scaling of lines, rather than just horizontal scaling of pixels. (See, e.g., '654 patent, at Figs. 4, 5, 6, 1:34-38, 1:63-2:7, 4:51-53, 5:19-64) More importantly, "the plainness of the claim language necessarily affects what ultimate conclusions about claim construction can properly be drawn based on the specification." Straight Path IP Grp., Inc. v. Sipnet EU S.R.O., 806 F.3d 1356, 1361 (Fed. Cir. 2015) ("[Disavowal is required where claim language is plain, lacking a range of possible ordinary meanings in context."). Here, the claim language - "scaling... to fill vertical resolution" - requires an actual change in vertical resolution. The proper resolution of the parties' claim construction dispute must ensure that claim limitation (b) is not eviscerated.[7]Further, the Court concludes that the patent refers to scaling in fields rather than scaling in images.

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It's exciting to play guitar. This builds better motor skills, boosts creativity, and relieves stress. Read this article if you want to learn about playing the guitar.

Build up your foundation. Do not try to learn too much too quickly. You might want to play a favorite song of yours, but the foundation you build is important. The first thing you must learn is finger positions. Chords and scales are the things you need to practice. Learn them before you try the advanced concepts.

Look for a good guitar teacher. It can be better to have someone watch you playing a guitar, even though you can learn on your own. They can help you with your style and show you ways to improve. You can also get your questions answered by them which can help a lot.

Figure out how you can be more motivated. Both long-term and short-term goals will help you progress on the guitar. If someone you know plays, join up with them for a music session every now and again. If you practice every day for a week, give yourself a reward when the week is over. Nothing valuable or worthy is easy to gain!

Buy a guitar. It can be hard to practice if you don't have one. Also, it is important to keep your guitar tuned, otherwise the sound you hear when you play will sound wrong even when it's right.

Make sure you're enjoying yourself when playing the guitar. Remember that you're only learning to play because you wanted to! Try not to make the learning process feel like work. This attitude may cause you to be bored, hate the guitar and completely stop practicing. Instead, practice and play music that you love and that speaks to you.

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From the structured sounds of classical guitar to the rowdy sounds of rock and roll, start simple when learning to play the guitar. Rather than attempting to learn hard songs, begin with simple tunes. Though you may feel silly, children's songs can offer some simple, single-note melodies that will be easy to follow and build your skill.

When learning songs, you should try playing them in different keys. The same song sounds different in varying keys, and you will learn chords more easily. Also, it will enhance your understanding of how music is created. You'll have a better understanding of music and be a better musician for it.

Begin working on playing slowly. When you want learn a song, take your time and learn it completely before trying to play it at tempo. Begin with learning the song note by note, then you can ramp up your speed. If you're only focusing on the speed you play at it's easy to get frustrated at your own mistakes. So, it is better to start things off very gradually, learn the song, and then let the speed come to you.

Do not spend a lot on the guitar that you initially purchase. It is easy to feel it necessary to buy the best guitar on the market, no matter the cost. This is often a mistake. You might discover you don't care for playing guitar. Plus, it is possible for a low cost guitar to sound good. Only make a real investment in your gear once you're sure guitar playing is something you want to commit to.

Find a guitar buddy. Ask around to find out who plays, and ask if you can get together. You may learn some techniques that are new to you. Also, playing and learning with friends or family makes the time fly by. If you find someone who is also beginning then you can teach each other.

Be sure to learn each song you attempt from start to finish. Just learning the catchiest section of any song can be surprisingly easy and tempting. This is a very poor habit to develop. Practice playing the entire song and force yourself to learn it. Keep your attention honed on learning the song until you have it down pat.

After you buy your guitar and start practicing on it, be sure to take care of it properly. Cleaning and maintaining it properly can make it last for years. Learn what you can to clean it, change your strings, and tune it. This will allow you to always have an instrument you're proud of.

Try asking someone to play a duet with you while you learn. Decide who is playing the melody and who plays the chords. This can be a fun way to get better at guitar. It also helps you establish a steady rhythm and tempo because you have to play with someone.

It is easy to see that there is much to learn when it comes to playing guitar. You should learn how to use your fingers and adopt new styles. Start using these tips the next time you play the guitar to see how good you can be.


The A.I. Chronicles (The Future Chronicles)

Samuel Peralta, David Simpson, Chrystalla Thoma, Pavarti K. Tyler, Susan Kaye Quinn

Format: Paperback

Language: 1

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Size: 5.84 MB

Downloadable formats: PDF

Science Fiction in the Twentieth Century. In the Chinks of the World Machine: Feminism and Science Fiction. They were also no doubt influenced by the 1932 publication of Aldous Huxley’s Brave New World. I wish Manhattan condo towers could be required to have street frontage consisting of capsule micro-shops. And so in accordance with the film’s logic, Godzilla truly is the ‘alpha predator,’ ruling over both MUTOs and mankind alike. Harry Winston came calling, and a collaboration on the Opus V ensued.

Pages: 430

Publisher: Windrift Books (March 13, 2015)

Some readings in relevant scholarship and The course format is mixed lecture and discussion. Gain a broad understanding of the history of English-language science ﬁction literature since 1890 in terms of its diverse forms, themes, and publication media. Develop the ability to analyze individual or multiple science-ﬁction texts in terms of key concepts including genre, implied audience, plot construction, linguistic texture, authorial identity, publication context, and sociocultural context Includes material for MedTechs well worth science fiction viewing , cited: Dick (which later became the movie Blade Runner) (McCaffrey, 17-20). The beginning of the literary movement that we can best recognize as cyberpunk really got going in the 1980’s In the process, the franchisers had taught a generation of readers and viewers -- and writers! -- to prefer predictable sameness, not surprising variety. If it appeared at all, variety was just ever-bigger special effects, rendered by ever-bigger computers online. It looks at future or past scenarios while considering what would happen if a particular technology had been successfully developed or seen widespread adoption by society , source: Currently the genre is more concerned with the artistic and physiological impact of nanotechnology, than of aspects of the technology itself. Still, one of the most prominent examples of nanopunk is Crysis video game series. And much lesser famous examples is Generator Rex and Transcendence. [8] As new writers and artists began to experiment with cyberpunk ideas, new varieties of fiction emerged, sometimes addressing the criticisms leveled at the original cyberpunk stories Improvements in prosthetics and brain computer interface have resulted in brain controlled prosthetics, a mainstay of cyberpunk. Corporations increasing dominate global politics, and influence culture creating a situation ripe for subversion. The poor are getting poorer and the rich are getting richer, creating a larger and larger divide pdf.

Rezolution - For those who demand more from their hobby. to steal or spread mayhem, fighting in the deadly game of winner takes all. fighting the corruption from within However, well-read SF readers should be familiar with all of the authors listed below , cited: The careless technophilia of those days belongs to a vanished, sluggish era, when authority still had a comfortable margin of control. For the cyberpunks, by stark contrast, technology is visceral. It is not the bottled genie of remote Big Science boffins; it is pervasive, utterly intimate , cited: Critical assessment of cyberpunk ranges from those who approach it with scorn to those who view it as a legitimate literary exploration of life in the post-humanist age pdf. Why can't people who think of themselves as top writers see any possibility of explaining the multiplicity of thinking, of life-styles, of processes around the world? DS: If we believe, as I believe, that any piece of writing is determined by its implied reader—modern literary theory maintains there is an ideal reader inscribed between the lines, an ideal addressee—it's not difficult to find the ideal reader of cyberpunk: computer hackers, media mixers, technicians of TV and radio stations, mobile young professionals, free-lancers, jet-setters who don't care whether they work in Tokyo, London, D�sseldorf, or Los Angeles—they just want to have their machines, they want to be part of a global network , source:
Books are physical objects that need to be manufactured and transported and sold, or digital entities that need to be formatted and made available online. Sometimes there are things we wish they would do a little more of: editorial standards are not what they were , cited: Each contributor will need to sign a contract to be emailed to authors whose work is accepted , cited: Excerpt and then a comment: There was Malaysian magic present the British Fantasy Awards yesterday (Sept 25). Selangor-born Zen Cho was voted Best Newcomer for her book, Sorcerer To The Crown, at the awards held at FantasyCon 2016 in Scarborough, England Since Neuromancer, Gibson has become a regular science fiction author and has written several books, most notably the Sprawl Trilogy (starting with Neuromancer), The Difference Engine, and the Bridge Trilogy , e.g. Where Cyberpunk portrays the future as a Crapsack World, Post-Cyberpunk posits society will probably be about the same, just with cooler gadgets. Where Cyberpunk is futuristic, forward thinking and on the cutting edge... so is Post-Cyberpunk Shortly thereafter, however, many critics arose to challenge its status as a revolutionary movement. These critics said that the SF " New Wave" of the 1960s was much more innovative as far as narrative techniques and styles were concerned. Further, while Neuromancer's narrator may have had an unusual "voice" for science fiction, much older examples can be found: Gibson's narrative voice, for example, resembles that of an updated Raymond Chandler, as in his novel The Big Sleep (1939) The works of cyberpunk science fiction writers are the birthplace of the concept of " cyberspace ". This concept was first introduced to the world by writer William Gibson in his novel " Neuromancer ", probably the most famous cyberpunk book ever. "Cyberpunk literature, in general, deals with marginalized people in technologically-enhanced cultural 'systems'. In cyberpunk stories' settings, there is usually a 'system' which dominates the lives of most 'ordinary' people, be it an oppressive government, a group of large, paternalistic corporations, or a fundamentalist religion download.
The advances of the sciences are so deeply radical, so disturbing, upsetting, and revolutionary, that they can no longer be contained. They are surging into culture at large; they are invasive; they are everywhere. The traditional power structure, the traditional institutions, have lost control of the pace of change ref.: But what I meant was, are any of the BBS boards listed here even up anymore? I tried connecting to a few and they don't seem to work We go Siamese twin on 'em before they even get restless. (Gibson 163) This virus is far more akin to the kinds of viruses we see today: programs that deceive operating systems and cause damage below the radar, indicating Gibson’s considerable (and rather astounding) foresight. Certain of Gibson’s technologies are logical evolutions of existing technologies, like the dermapatches used to take drugs , cited: That is, stories that have previously been published by a paying market, NOT something self-published or placed on a free webzine. All submissions should: Word Count: 2,000 to 9,000 words preferred, but flexible. Be typed in Courier or Times New Roman 12. Be typed in line with Standard Manuscript Format ref.: Anti-authoritarian, brand-averse, tech-literate; these are just some of the qualities you may find in a cyberpunk , source: Il peut y avoir contestation au sujet de la classification des différents sous-genres du cyberpunk : par exemple, on considère le steampunk et le biopunk comme des sous-genres mais, les caractéristiques de ces sous-genres du cyberpunk étant relativement vastes et encore assez proches des caractéristiques définissant le cyberpunk, un chevauchement peut aisément survenir lors d'une identification d'une œuvre au cyberpunk et à ses sous-genres Jameson is not so easily convinced that Gibson is really post-cyberpunk, and opines “Maybe, on the contrary, he is moving closer to the ‘cyberpunk’ with which he is often associated.” He then suggests that the critics bringing Gibson into the “Fiction” fold are actually doing him a disservice, as Jameson validates cyberpunk and science fiction as essential reflections of current society which “Fiction” by its omission in his statement, seems unable to present She’s also won 11 Hugos, 11 Locus Polls and 8 Nebulas. The awards aside, she’s a clear choice for a top female science fiction author. Her superbly humorous sci-fi tales are also balanced with some gravitas, like asking what impact technology will really have on society? Expect multi-layered characters and a slow humor build online. Let's say the best of cyberpunk can be read—with many impurities—as a kind of Rousseauist rebellion pdf. It seems light I read some John Wright a few years back, he did the Golden Age, yes? I'll look into Ellis & Sean Williams also. Anyway, thanks to everyone who posted here, I've got about a years worth of suggestions to read and alot of them sound really cool. I think I may have given up too early on the CP thing. It's completely different from what I'm used to, but I think it has a lot to offer

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Authors Name:
Jack Fitzsimons
Trinity College Dublin
Computer Sciences
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Identifying Abandoned, Moved and Removed Objects in Automated Surveillance Systems

This project is concerned with the classification of long term changes in surveillance scenes, known as static foreground. There has been little work related to such classification despite its potential role in automatic identification of abandoned bombs and theft. In this project, a thorough literature review of previous techniques was conducted. All previous static foreground classifiers were limited to classifying objects as either abandoned or removed. This leads to many ambiguous cases whereby objects move, such as a bin falling over in the wind. I implemented each of these techniques and a comparison of their performance has been evaluated on a test set of 40 examples of abandoned and removed objects taken from established benchmarks. Classifying static foreground as an abandoned, removed or moved object presents new issues. Firstly, the static foreground observed no longer necessarily indicates the position of an object in the scene. Secondly, previous techniques relied on computing a metric from before and after the static foreground was detected which work in the constrained conditions of abandoned and removed objects, but break down for multi-class classification. In order to overcome these challenges a four stage system is presented. Leveraging the strengths of previous abandoned and removed classifiers, the system combines image inpainting, pixel level classifiers and image segmentation to create robust classifications. The first two stages overcome the issues associated with the static foreground of moved objects. The latter stages deal with the multi-class classification. The system was tested on 80 examples of abandoned, removed and moved objects and operated at 95% accuracy. Previous methods classified moved objects arbitrarily between abandoned and removed as the classification was outside their scope. The proposed system resolves this challenge and also matches the previous state of the art abandoned and removed object classifier in the absence of moved objects.


Stage 8 Stage 9 Stage 10

Let’s start with some vocabulary. In the UK, a pound is called a ‘quid’. ‘Have you got a quid?’ means ‘Have you got a pound?’ Note that we don’t pluralise this noun when talking about an amount of money, i.e. we say ’50 quid’ and not ’50 quids’. However we do use ‘quids’ in the expression ‘quids in’, which means ‘to make a profit’, e.g. ‘When we sold the house we were quids in.’ But ‘quid’ is only pluralised in this expression, not when used as a noun in general.

If we have five pounds, we have five quid. However we also have a ‘fiver’. This refers to the five pound banknote. We can go further with this, and indeed some Londoners do – particularly those from the East End of London (Cockneys), who refer to a fiver as a ‘lady’, after the historical British figure Lady Godiva, whose name rhymes with ‘fiver’.

Similarly, a tenner means ten pounds (or ten quid) and generally refers to the note, rather than ten pounds in coins. Some people will call it an ‘Ayrton’, after the late Brazilian Formula 1 racing driver Ayrton Senna (as Senna rhymes with ‘tenner’).

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Speaking of coins, when we are searching amongst our ‘small change’ – i.e. penny coins and 2p coins – we are looking through our ‘coppers’. This does not have any connection to a ‘copper’ as a policeman (‘cop’ for short). It refers instead to the colour of the coins rather than the material they are made from, as most British coins these days are actually made from copper-plated steel.

Let’s look at a few money idioms. If you (or your company) is ‘in the black’, don’t worry: this is a good thing. It means you are not in debt (for now, at least). Keep things this way! If, alternatively, you are already in the red, you need to act: you owe money and are not making profit. Sometimes you need to ‘break the bank’ to make advances and revive your company’s fortunes. ‘Breaking the bank’ means to spend more money on something than you normally would, e.g. ‘he broke the bank when he bought the new PC for the office’).

When we have no money, we say we are ‘broke’, ‘skint’ or ‘strapped for cash’. These words mean the same thing: we are poor! We might then look at a rich person with envious eyes and remark on how they are ‘loaded’ or ‘filthy rich’. This means they have a lot of money (e.g. ‘Bill Gates gives a lot of money away to charity – he’s loaded’).

To progress from this penurious state to one of affluence would require one to go ‘from rags to riches’. This expression is used to describe a person’s meteoric rise, from humble origins, into the ranks of the wealthy.

We might be especially envious of a person who is born into a wealthy family. When somebody is rich due to their family connections, we say they were ‘born with a silver spoon in (their) mouth’. They can afford to spend what they like on luxury items: we, meanwhile, have to ‘live within our means’, i.e. not spend more than we have. We should avoid the temptation to ‘use credit’ to fund our purchases (to use a credit card to buy things). We certainly should not gamble the money we have away: when a man loses all his money through betting or dubious business deals, we say ‘he lost his shirt’ – sometimes literally.

Take our blog test to see how you manage with a few of the idioms we’ve looked at in this blog.

A. Porter

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Serena warns her Wimbledon rivals | 2018-07-10 |

Serena warns her Wimbledon rivals

AFP     10th July, 2018 12:32:16 printer

Serena warns her Wimbledon rivals

Serena Williams has warned her Wimbledon rivals she is nowhere near her best despite powering into the quarter-finals without dropping a set.

Williams is chasing an eighth Wimbledon crown and the American star showed why she is the title favourite with a 6-2, 6-2 demolition of Evgeniya Rodina in the fourth round on Monday.

In her 13th Wimbledon quarter-final, Serena faces Italian world number 52 Camila Giorgi on Tuesday.

The path to the title appears wide open for the 36-year-old after every female top seed crashed out before the last eight for the first time in Wimbledon history.

The carnage at the top leaves 11th seed Angelique Kerber -- beaten by Serena in the 2016 Wimbledon final -- as the highest ranked player left.

Williams isn't complaining about the high number of shock results, but she couldn't resist at jab at the Wimbledon organisers who only seeded her 25th despite her remarkable record.

"I faced a thousand and three seeds in my life, so I'm okay," she said.

"Things happen. On both sides, men's and women's, there's been a tremendous amount of upsets.

"I don't think this has happened to this extreme. But also I've never been ranked where I am when this has happened before, so usually I'm one of those few seeds left that's still fighting and still in the tournament.

"Now that I'm not, it kind of happened!"

It's not as if Serena needs much encouragement to dominate at Wimbledon, where she has already reached nine finals.

Having shaken off the rust following her lenghthy lay-off after the birth of her daughter Olympia in September, she is rounding nicely into form for the business end of the tournament.

Ominiously for the other seven women left in the draw, the 23-time Grand Slam champion, who missed Wimbledon last year but won the title on her previous two visits, insists there is still plenty of room for improvement.

"There's a lot to improve on. This is only my fourth tournament back," said Williams, who has won all three of her previous meetings with Giorgi.

"For me, there's so much farther I want to go to get back where I was, and hopefully go beyond that.

"I'm always striving for perfection. There's a lot of things that, I don't know if you can tell, but I really need to work on. Hopefully I can get there."

No pressure

Of ther other quarter-finalists, only Kerber and former French Open champion Jelena Ostapenko have won Grand Slams.

Kerber, who won the Australian and US Open in 2016, takes on Russian 14th seed Daria Kasatkina.

"I'm not feeling the pressure because I'm not looking on the seeded or who is left or not," Kerber said of her improved title chances.

"For every single day that I'm here trying to do my best. This is all I'm focusing on. It's still a long way until the end."

Latvian 12th seed Ostapenko plays former Australian Open finalist Dominika Cibulkova.

"At the French Open I had all that pressure, now it's gone," former junior Wimbledon champion Ostapenko said.

"I'm just not afraid to miss. I'm just going for the shots."

Kiki Bertens took care of the last of the top 10 with a 6-3, 7-6 (7/1) victory over Czech seventh seed Karolina Pliskova.

Bertens, who was contemplating retirement last year after losing her enthusiasm for the sport, is the first Dutch woman to reach the Wimbledon quarter-finals since Michaella Krajicek in 2007.

The 26-year-old faces German 13th seed Julia Goerges, who beat Donna Vekic to seal her first Grand Slam quarter-final berth at the 42nd attempt.

"This is for me something pretty special," Goerges said.

"It sounds pretty strange when you saw my record from the last five years here. I didn't expect it, honestly."


The Run

After escaping her kidnapper, Samantha runs for her older brother Liam Payne. When things start to go back to normal,she starts falling for his friend. Harry Styles. What will happen, and will love conguer all?

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Music History for

September 23

1923 - "720 in the Books" was recorded by Jan Savitt and his Orchestra.

1952 - Hank Williams did his last recording session.

1956 - Micky Dolenz began his television career in NBC's "Circus Boy" series. He later became a member of the Monkees.

1966 - The song "Have You Seen Your Mother, Baby?" was released by The Rolling Stones in the U.S. and U.K.

1967 - "People Are Strange" was released by the Doors.

1969 - It was reported by "The London Daily Mirror" that Paul McCartney was dead. It was the first time the rumor was printed.

1974 - Robbie McIntosh (Average White Band) died of a heroin overdose at the age of 24.

1980 - David Bowie made his acting debut in the Broadway show "The Elephant Man". He performed the role until January 3, 1981.

1980 - Bob Marley performed his last show in Pittsburgh, PA. He died seven months later of cancer.

1996 - In Sweden, Agnetha Faltskog (Abba) published her autobiography "As I Am."

1997 - MCA Records reissued Average White Band's label debut "Show Your Hand" as part of the band's 25th anniversary.

1997 - The album "Falling Into Infinity" was released by Dream Theater.

1997 - Elektra Entertainment released "The Next Voice You Hear: The Best of Jackson Browne."

1997 - Elton John's single "Candle in the Wind 1997" was released in the U.S.

1998 - The first Lilith Fair concert outside North America took place at London's Royal Albert Hall.

1999 - Shirley Manson (Garbage) unveiled her own line of lip gloss.

1999 - Coolio appeared on TV's "Judge Joe" to settle a financial dispute with his backing band the Wyld Bunch. The judge ruled the band was due $4,000 in unpaid earnings.

2003 - The Outkast album "Speakerboxxx/The Love Below" was released.


Mount Greenwood Elementary School Modular

10841 South Homan Avenue

The project will include the fabrication and installlation of a six-classroom modular, including associated site work, and power/communications connections to the adjacent existing building as needed. The project includes the relocation of a playground on the property, currently located where the modular will be installed. This project will also include the upgraded exterior building scope of work including but not limited to cement board and metal panel cladding, parapet, scuppers, elongated casement windows, and lit recessed building entries.


Lobi Bateba Duntundara figure also known as Bateba Ti Puo
I have also seen them referred to as "Duntundora"
The Lobi people live in a vast geographical area that stretches from Burkina Fasso, to the Ivory Coast and into Ghana. Villages are spread out over
wide areas and are made up of several compounds.

The Lobi community is not organized on the basis of kinship or political ties and lacks any kind of centralized political authority in the form of a chief
king or council of village elders. Instead the members of the community are united by common adherence to the cult of a nature spirit called “thil” (pl
thila) and the rules that determine correct social behavior in the community are the rules that the spirit dictates through the diviner (thildar). The thila
are invisible spirits of nature with certain supernatural abilities and powers that they can use for malevolent or benevolent ends. Each village has a
particular spirit (dithil) that is responsible for the entire village.

Social behavior is regulated by these thila, whose will is passed to ordinary people by priests and diviners. Wooden or clay sculpture, called bateba, act
as an intermediary between a particular thil and the Lobi community.

Lobi bateba figures have a wide degree of style and are made for a wide range of purposes. In Lobi communities anyone can learn to carve, it is not
limited to people with specialized training. Lobi bateba figures are believed to be able to act in behalf of their owner, they are considered a living being
and have the ability to act out against forces that could harm it’s owner or bring good things to it’s owner depending on it’s intended purpose.

Very basic definitions

BATEBA PHUWE  - Normal or ordinary Bateba
These figures usually have no specific defining posture and are often figures with arms straight down and the figures are looking straight ahead and
often have a grim look on the face. These figures can have a variety of different functions.

BATEBA Tl  BALA - Unusual or extraordinary Bateba (sub categories Thil Dokra <janus figure>, Betise <mating couple>, maternity figures)
Thil Dorka - Figures with two heads represent deities whose ability to see in several directions at once makes them exceptionally dangerous and
Betise - Figures depicting a man and a woman making love (the man always positioned behind the woman) are prescribed for single men so that they
find a wife or to women to avoid sterility or wished to have a child.

Some figures are carved with sad expressions or have a hand touching the face because their function is to mourn for their owners.

BATEBA Tl PUO  - Dangerous Bateba
Often referred to as Bateba Duntundara as well, these figures are considered dangerous and block entrance to harmful forces such as disease or
witchcraft, and are depicted with one or both arms held up.
BATEBA  BAMBAR - Paralysed Bateba
Figures depicting a seated man or woman with their legs stretched out in front of them are called bamgbar/bambar. According to certain soothsayers,
these protect children and the elderly from paralysis.

The Lobi often have conflicting interpretations of the meanings of the figures, and there are also varied meanings on similar figures because of
regional variances.

References: A History of Art in Africa, Lobi Art and Culture, The Lobi of Burkina Fasso, Lobi Skulpturen

If you are interested in learning more about the Lobi,
CLICK HERE to go to some great online reference articles.
Link will open in a new window.
Lobi Bateba Duntundara or Bateba Ti Puo figure

8.6" tall (22cm)
Provenance - Galerie-Verkauf, Germany
Photos of the Lobi shrines from:
More great photos in this site!
Information and photos below from:
Metropolitan Museum of Art
Shrine Figures: Couple (Bateba Phuwe)
Lobi, Burkina Faso
Wood; male: H. 57.2 cm (22 1/2 in.); female:
H. 46.4 cm (18 1/4 in.)
20th century
Thomas G. B. Wheelock Collection
The impetus for the creation of these works and the manner in which they should ideally appear came from spirits who
conveyed the desired images through the medium of a diviner. Their subsequent realization fulfilled a prescription that
resulted in curing an ailment or otherwise relieving some personal difficulty.

According to Lobi conceptions of existence, God (thangba yu), the Creator of all life on earth, is an abstract and distant force.
(1) More directly engaged in human experience are the thila, invisible and bodiless beings endowed with superhuman powers
and abilities. Through the medium of diviners (buor), the thila issue injunctions against certain kinds of behavior; anyone who
violates them will be punished with an ailment or some other misfortune. They also provide the means to reverse these
conditions by prescribing cures and protective measures, also conveyed through buor.

This dynamic was set in place by thangba yu in order to establish standards of political, social, and moral order in Lobi society,
which humans had been incapable of managing by themselves. At the time of creation, according to oral traditions, humankind
had enjoyed a carefree state in which thangba yu had provided for all its needs, a world where sickness and death were
unknown, as were war or conflict of any kind. As a requirement of these idyllic conditions, thangba yu prohibited adultery and
killing—commandments that were violated when the population grew out of control. Consequently, thangba yu retreated
forever, leaving humanity to provide for itself and vulnerable to suffering and mortality. To mitigate this isolation, the Creator
assigned to the thila the responsibility of responding to human needs and protecting people against witchcraft and sorcery.

The directives (bonoo) given to individuals through buor are very exacting and must be fulfilled with precision. Failure to do so
is thought to lead either to some form of punishment by the thila or to the persistence of the difficulties being experienced.
Because they are amorphous beings, the thila depend on human mediums to communicate their instructions. Thila select
individuals to fulfill this role by revealing themselves directly to them, or through notifying other diviners. Individuals usually
resist this calling, as it is considered an onerous responsibility in view of the time commitment it represents and its lack of
remuneration. Training is relatively informal and consists of observing consultations and rituals and learning the signs that the
thila use to communicate.(2)

Individuals consult diviners to gain insight into a broad range of situations that concern them. They enter into this relationship
without describing the problem at hand. Instead, the diviner positions himself beside the client, grasps his hand, and, in order
to determine independently the nature of the problem and which thila is involved in this particular situation, poses a series of
questions that can be responded to with "yes" or "no" answers. Responses are indicated through specific movements of their
joined hands.(3) A diagnosis ultimately reveals behavioral prohibitions that must be followed, sacrifices that are required, and
instructions that may request the construction of a shrine or the commissioning of figural sculpture (bateba).(4)

Small wood figurines are often part of the collection of paraphernalia owned by the buor, whereas works that are
commissioned to fulfill prescriptions are larger in scale. The sculptor (bateba thel), who may himself have been directed toward
his vocation by his thila, carefully follows the guidelines for such works, provided by the spirits through the diviner.(5) This
couple represents a unified vision of the human form but displays subtle distinctions between the male and female figures.
Although the female is slightly smaller in scale, she shares the same bold rectilinear cast, crisply rendered features, and
gradually swelling torso with a pronounced navel. Both are depicted in a state of intense concentration, eyes closed and lips
pursed, the male figure facing forward while his female counterpart turns her head in profile. This creates a dramatic shift
between the orientation of their bodies and her gaze.

Lobi figural sculptures commissioned as a result of a divination consultation represent tibila thil, people who help a spirit, and
are designed to be placed in a residential or public shrine.(6) These two figures are thought to be bateba duntundara, a genre
of bateba that serve to shield their owner against the witches that might attempt to enter his or her home.(7) Duntundara can
be found in a broad range of representations, including figures that gesture dramatically or feature unusual physiological
characteristics such as multiple heads or arms. Standing with their arms at their sides, this couple falls into a category of
"plain" (phuwe) figures. Despite their tranquil stance, they embody an attitude of vigilance and acute awareness that
surpasses ordinary reliance on sensory perception and intimidates potential malefactors.

1. Piet Meyer in Peek 1991, p. 92.

2. Ibid., p. 94.

3. Labouret 1931, p. 453; Piet Meyer in Peek 1991, p. 96.

4. Piet Meyer in Peek 1991, pp. 98–99.

5. Ibid.

6. Meyer 1981b.

7. Piet Meyer, Kunst und Religion der Lobi, exh. cat. (Zurich: Museum Rietberg, 1981), p. 56; Meyer 1981a, pp. 21–22.

Source: Metropolitan Museum of Art
LOBI brass Chameleon in my collection
A really great piece in a private collection
A Lobi figure from the Maurer Collection

bateba Figure
A Lobi figure from the Maurer Collection

bateba Figure
A group of late 19th/early 20th century Lobi figures
Height: 17,3 to 53,5 cm
Collection du Musée des Beaux-Arts d'Angoulême (Poitou-Charentes)
A Lobi figure from the book:
African Art in American Collections
Mr. and Mrs. William W. Brill Collection
A Fantastic set of Lobi figures from the book:
African Art in American Collections
Both figures aprox 28" tall
Fred and Rita Richman Collection