bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring Animal Personality for Use in Population Management in Zoos: Suggested Methods and Rationale
Authors: Watters Jason V. , Powell David M.
Published: March 2011

The concept that animals have personalities is gaining traction in the scientific community and is well established in zoos and aquariums. Applying knowledge of animal personalities has occurred more slowly and is most often only considered informally. However, animal personalities are likely to affect the welfare animals experience in captivity and thus should be of primary concern to zoo managers. In addition, animal personality likely affects the outcomes of zoo guest experiences and potentially guests' conservation‐related behavior. With over 1,000,000 animals in the care of zoos internationally and hundreds of millions of visitors annually, it would be prudent and beneficial to maximize our use of animal personality data in zoos to effect positive conservation outcomes. Understanding how to broaden population planning techniques to include measures of animal personality and the important outcomes of welfare and education value is of prime importance to the zoo industry. In order to succeed, it is necessary to employ techniques that reliably assess animal personalities and provide measures that can easily be used in population planning models. We discuss the outcomes of recent workshops designed to determine the best techniques for measuring animal personalities in the zoo setting with the goal of incorporating personality into population planning. Zoo Biol 31:1;–12, 2012. © 2011 Wiley Periodicals, Inc.
IGAD as an International Organization, Its Institutional Development and Shortcomings
Authors: Weldesellassie K Isaac
Published: March 2011

The heads of state and government of the East African sub-region established a forum known as the Inter-Governmental Authority on Development (IGAD) for expanded cooperation in 1996. The conclusion of the treaty by which IGAD was created was the beginning, not the end, of commitment to IGAD through the principle ofpacta sunt servanda[agreements are binding and must be implemented in good faith]. In spite of the great hopes, optimism and aspirations placed on the creation of IGAD, the challenge then become IGAD members' commitment to the treaty establishing IGAD. If member states are unable to grant powers to IGAD and cooperate to enable IGAD to execute its objectives, IGAD cannot work as was intended, hence it remains open to questions. This article discusses IGAD's fundamental features and the institutional progress it has achieved, as well as the challenges it faces as an international legal body.
Entrenching the Right to Participate in Government in Kenya's Constitutional Order: Some Viable Lessons from the African Charter on Human and Peoples' Rights
Authors: Mbondenyi Morris Kiwinda
Published: March 2011

A practice of frequent constitutional amendments started shortly after Kenya attained her independence in 1963. Consequently, the country has witnessed a confusion of systems of governance, ranging from single-party autocracy to virtual multi-party democracy, which have served to endorse the chronic condition of human rights violations in the country. In the process of such experimentation, Kenyans have unabatedly been denied the enjoyment of many of their fundamental rights and freedoms, including the right to participate in their government. This article analyses Kenya's constitutional order with the intention of highlighting the extent to which the country's citizens have been denied the right to participate in their government. Drawing inspiration from the African Charter on Human and Peoples' Rights, the article recommends ways in which this right could be entrenched in the country's constitutional order.
Corporate Criminal Liability in South Africa: The Need to Look Beyond Vicarious Liability
Authors: Nana Constantine Ntsanyu
Published: March 2011

Corporate criminal liability is a problematic concept, especially where it is based on an exceptionable principle such as vicarious liability. This is the case with the South African model. This article seeks to demonstrate that this model requires substantial modification because it compels the court to adopt the incoherent exercise of holding a corporation (which is a distinct person) liable for the intentional act (crime) of any of its agents, whether or not there is criminal intention on the corporation's part and whether or not it was aware of, or could have prevented the commission of the offence. It is submitted that it is more appropriate to hold a corporation liable only where it has been established that the course of conduct that resulted in the offence was encouraged or tolerated by persons who embody the corporation (usually sufficiently empowered managers or members of the board of directors).
Nigeria's National Content Bill: The Hype, the Hope and the Reality
Authors: Nwaokoro Joseph Nna Emeka
Published: March 2011

Nigeria's recent efforts to pass local content legislation with stringent targets and stiff penalties have drawn widespread attention, spurred ongoing debate and prompted numerous international workshops and seminars. Lack of local content has been blamed for high unemployment and lack of capacity, and even been linked to militancy in the Niger Delta region. After much debate and delay, the bill has become law. This article reviews the bill's history and tracks the hype surrounding Nigeria's moves towards a legislative mandate. It discusses the provisions of the bill, observing that it is poorly drafted, vague and therefore difficult to comply with. The bill could also violate international agreements, such as bilateral investment treaties and GATT, and is unnecessary in the face of contractual alternatives that could be successfully utilized to enhance local content. Contract models contain ample provisions for enabling local content and have been successfully employed by other resource-rich nations.
Ambulatory Position Tracking of Prosthetic Limbs Using Multiple Satellite Aided Inertial Sensors and Adaptive Mixing
Authors: Vepa Ranjan
Published: March 2011

In this study, satellite based pseudo-range measurements are integrated with accelerometer measurements made by six accelerometers located on the six faces of a cuboid, to independently measure the translational and rotational accelerations, and the pseudo-range. These measurements are then processed by an adaptive Unscented Kalman filter (UKF) to correct for the estimated errors and to obtain the required position and velocities at two independent locations. The relative position and velocity are then obtained by the application of standard vector identities. From these estimates, the position and velocity kinematics of prosthetic limbs and measurements of the joint angles, the true ambulatory position is estimated using a third independent UKF based estimator. The robotic limb joint offsets are assumed to be biased which are also estimated by the third UKF. The basic assumption is that the errors in the measurements are quite similar at the two locations and for this reason it is hypothesised that these errors would be reduced when the relative position and velocity were estimated. The results indicate that the steady-state ambulatory position error of the end-effector is reduced by more than 98%.
Aiding Low Cost Inertial Navigation with Building Heading for Pedestrian Navigation
Authors: Abdulrahim Khairi , Hide Chris , Moore Terry , Hill Chris
Published: March 2011

In environments where GNSS is unavailable or not useful for positioning, the use of low cost MEMS-based inertial sensors has paved a way to a more cost effective solution. Of particular interest is a foot mounted pedestrian navigation system, where zero velocity updates (ZUPT) are used with the standard strapdown navigation algorithm in a Kalman filter to restrict the error growth of the low cost inertial sensors. However heading drift still remains despite using ZUPT measurements since the heading error is unobservable. External sensors such as magnetometers are normally used to mitigate this problem, but the reliability of such an approach is questionable because of the existence of magnetic disturbances that are often very difficult to predict. Hence there is a need to eliminate the heading drift problem for such a low cost system without relying on external sensors to give a possible stand-alone low cost inertial navigation system. In this paper, a novel and effective algorithm for generating heading measurements from basic knowledge of the orientation of the building in which the pedestrian is walking is proposed to overcome this problem. The effectiveness of this approach is demonstrated through three field trials using only a forward Kalman filter that can work in real-time without any external sensors. This resulted in position accuracy better than 5 m during a 40 minutes walk, about 0·1% in position error of the total distance. Due to its simplistic algorithm, this simple yet very effective solution is appealing for a promising future autonomous low cost inertial navigation system.
Exploring the Influence of Income and Geography on Access to Services for Older Adults in British Columbia: A Multivariate Analysis Using the Canadian Community Health Survey (Cycle 3.1)
Authors: Allan Diane E. , Funk Laura M. , Reid R. Colin , Cloutier-Fisher Denise
Published: March 2011

Les recherches existantes sur les modes d’utilisation des soins de santé des Canadiens âgés suggèrent que habituellement le revenu ne restreint pas l’accès d’une personne. Cependant, le rôle que joue le revenu en influençant l’accès aux services de santé par les personnes âgées vivant en milieux ruraux est relativement inconnu. Cet article examine la relation entre le revenu et l’utilisation des services de santé chez les personnes âgées dans les zones rurales et urbaines de la Colombie-Britannique. Les données ont été extraites de l’Enquête sur la santé dans les collectivités canadiennes (ESCC) de Statistique Canada, cycle 3.1. Avec une régression multivariable, on a examiné l’influence du revenu sur l’accessibilité de 3 424 personnes âgés de 65 ans et plus. Les résultats suggèrent que (1) de faible revenu n’influence pas l’accès aux services de soins de santé, et (2) que cela est vrai pour les adultes âgés urbaines et ruraux. Dans tous les cas, les prédicteurs les plus importants et cohérents d’accès sont ceux qui ont mesuré le besoin de soins de santé.
Nematode communities of Byers Peninsula, Livingston Island, maritime Antarctica
Authors: Nielsen Uffe N. , Wall Diana H. , Li Grace , Toro Manuel , Adams Byron J. , Virginia Ross A.
Published: March 2011

The nematode communities of Antarctica are considered simple. The few species present are well adapted to the harsh conditions and often endemic to Antarctica. Knowledge of Antarctic terrestrial ecosystems is increasing rapidly, but nematode communities remain to be explored in large parts of Antarctica. In soil samples collected at Byers Peninsula (Antarctic Specially Protected Area No. 126), Livingston Island we recorded 37 nematode taxa but samples showed great variation in richness and abundance. Nematode richness decreased with increasing soil pH, whereas total abundances, and the abundance of several trophic groups, were greatest at intermediate pH (around 6.5–7). Moreover, the community composition was mainly related to pH and less so to soil moisture. Trophic group, and total nematode, rotifer and tardigrade, abundances were generally positively correlated. Byers Peninsula is thus, by maritime Antarctic standards, a nematode biodiversity hotspot, and the presence of several previously unrecorded genera indicates that nematode species richness in maritime Antarctica is probably underestimated. Our results indicate that abiotic factors influence nematode communities with little evidence for biotic interactions. The unexplained heterogeneity in community composition is probably related to variation in microclimate, vegetation, topography and unmeasured soil properties, but may also be contributed to by biological processes.
Skin-digging tanaids: the unusual parasitic behaviour of Exspina typica in Antarctic waters and worldwide deep basins
Authors: Alvaro Maria Chiara , Błażewicz-Paszkowycz Magdalena , Davey Niki , Schiaparelli Stefano
Published: March 2011

The order Tanaidacea includes over 1000 species which are mainly free-living or tube-dwelling detritivores. Exspina typica Lang, 1968 represents an exception to these common life styles, having being found in the intestine and body cavity of deep sea holothuroids. The 2008 New Zealand ‘IPY-CAML Cruise’ held in the Ross Sea collected several deepwater holothuroids that were observed to carry specimens of E. typica inside their coelomic cavity. A clear interpretation of this association was hence possible. Even if E. typica shows slight adaptations to a parasitic life style, the tanaids were found to actively ‘dig’ into the host's skin, grasping tissue with their claws and producing tunnels in the body wall. It is therefore possible to clearly define this association, which is here reported from the Antarctic for the first time, as parasitism.
Penguin cranial remains from the Eocene La Meseta Formation, Isla Marambio (Seymour Island), Antarctic Peninsula
Authors: Hospitaleche Carolina Acosta , Haidr Nadia
Published: March 2011

Widely accepted ideas about trophic preferences of early penguins suggest that all Eocene sphenisciforms were piscivorous. However, recent findings from the La Meseta Formation (Eocene) of Antarctica, support the presence of at least two different morphotypes that may have evolved as a niche partitioning strategy, which is consistent with the high diversity recorded. The first of them corresponds to a medium–large sized penguin, resembling the Neogene species in configuration. Another morphotype is represented by extremely large penguins with very long and slender bills, clearly linked to fish catching habits.
High-performance 60 GHz MMICs for wireless digital communication in 100 nm mHEMT technology
Authors: Lopez-Diaz Daniel , Kallfass Ingmar , Tessmann Axel , Weber Rainer , Massler Hermann , Leuther Arnulf , Schlechtweg Michael , Ambacher Oliver
Published: March 2011

Wireless data communication is pushing towards 60 GHz and will most likely be served by SiGe and Complementary Metal Oxide Semiconductor (CMOS) technologies in the consumer market. Nevertheless, some applications are imposing superior performance requirements on the analog frontend, and employing III-V compound semiconductors can provide significant advantages with respect to transmitter power and noise figure. In this paper, we present essential building blocks and a novel single-chip low complexity transceiver Monolithic Microwave Integrated Circuit (MMIC) with integrated antenna switches for 60 GHz communication, fabricated in a 100 nm metamorphic high electron mobility transistor (mHEMT) technology. This technology features a measured noise figure of <2.5 dB in low-noise amplifiers at 60 GHz and the realized medium power amplifiers achieve more than 20 dBm saturated output power. Integrated antenna switches with an insertion loss of less than 1.5 dB enable the integration of the transmit and the receive stages on a single chip. A single-chip transceiver with external subharmonic Local Oscillator (LO) supply for its I/Q down- and up-converter achieves a linear conversion gain in both, the Transmit (Tx) and the Receive (Rx) paths, of more than 10 dB.
Interfacial electronic structures at Fe/pentacene/Fe interfaces
Authors: Wang Yu-Zhan , Gao Xing-Yu , Wee Andrew , Qi Dong-Chen , Chen Shi
Published: March 2011

We investigate the interfacial electronic structures of the heterojunction Fe/pentacene/Fe on Cu(100) substrate, using synchrotron-based photoemission spectroscopy. No chemical reaction is observed at either Fe/pentacene or pentacene/Fe interface. The hole injection barrier was estimated to be about 0.95 eV between pentacene and under the Fe thin film. C K-edge NEXAFS revealed that the long axis of pentacene molecule was almost perpendicular to the surface plane. With increasing Fe thickness deposited on pentacene film, the pentacene's HOMO shifts to higher binding energy whereas the C 1s binding energy showed an interesting unusual behaviour due to the initial band bending gradually suppressed by the increasing core-hole screening effect.
Cellulose-degrading bacteria associated with the invasive woodwasp Sirex noctilio
Authors: Adams Aaron S , Jordan Michelle S , Adams Sandye M , Suen Garret , Goodwin Lynne A , Davenport Karen W , Currie Cameron R , Raffa Kenneth F
Published: March 2011

Sirex noctilio is an invasive wood-feeding wasp that threatens the world's commercial and natural pine forests. Successful tree colonization by this insect is contingent on the decline of host defenses and the ability to utilize the woody substrate as a source of energy. We explored its potential association with bacterial symbionts that may assist in nutrient acquisition via plant biomass deconstruction using growth assays, culture-dependent and -independent analysis of bacterial frequency of association and whole-genome analysis. We identified Streptomyces and γ-Proteobacteria that were each associated with 94% and 88% of wasps, respectively. Streptomyces isolates grew on all three cellulose substrates tested and across a range of pH 5.6 to 9. On the basis of whole-genome sequencing, three Streptomyces isolates have some of the highest proportions of genes predicted to encode for carbohydrate-active enzymes (CAZyme) of sequenced Actinobacteria. γ-Proteobacteria isolates grew on a cellulose derivative and a structurally diverse substrate, ammonia fiber explosion-treated corn stover, but not on microcrystalline cellulose. Analysis of the genome of a Pantoea isolate detected genes putatively encoding for CAZymes, the majority predicted to be active on hemicellulose and more simple sugars. We propose that a consortium of microorganisms, including the described bacteria and the fungal symbiont Amylostereum areolatum, has complementary functions for degrading woody substrates and that such degradation may assist in nutrient acquisition by S. noctilio, thus contributing to its ability to be established in forested habitats worldwide.
Impacts of anthropogenic activity on the ecology of class 1 integrons and integron-associated genes in the environment
Authors: Gaze William H , Zhang Lihong , Abdouslam Nouradin A , Hawkey Peter M , Calvo-Bado Leo , Royle Jeremy , Brown Helen , Davis Susan , Kay Paul , Boxall Alistair B A , Wellington Elizabeth M H
Published: March 2011

The impact of human activity on the selection for antibiotic resistance in the environment is largely unknown, although considerable amounts of antibiotics are introduced through domestic wastewater and farm animal waste. Selection for resistance may occur by exposure to antibiotic residues or by co-selection for mobile genetic elements (MGEs) which carry genes of varying activity. Class 1 integrons are genetic elements that carry antibiotic and quaternary ammonium compound (QAC) resistance genes that confer resistance to detergents and biocides. This study aimed to investigate the prevalence and diversity of class 1 integron and integron-associated QAC resistance genes in bacteria associated with industrial waste, sewage sludge and pig slurry. We show that prevalence of class 1 integrons is higher in bacteria exposed to detergents and/or antibiotic residues, specifically in sewage sludge and pig slurry compared with agricultural soils to which these waste products are amended. We also show that QAC resistance genes are more prevalent in the presence of detergents. Studies of class 1 integron prevalence in sewage sludge amended soil showed measurable differences compared with controls. Insertion sequence elements were discovered in integrons from QAC contaminated sediment, acting as powerful promoters likely to upregulate cassette gene expression. On the basis of this data, >1 × 1019 bacteria carrying class 1 integrons enter the United Kingdom environment by disposal of sewage sludge each year.
Signalling to actin: role of C3G, a multitasking guanine-nucleotide-exchange factor
Authors: Radha Vegesna , Mitra Aninda , Dayma Kunal , Sasikumar Kotagiri
Published: March 2011

C3G (Crk SH3-domain-binding guanine-nucleotide-releasing factor) is a ubiquitously expressed member of a class of molecules called GEFs (guanine-nucleotide-exchange factor) that activate small GTPases and is involved in pathways triggered by a variety of signals. It is essential for mammalian embryonic development and many cellular functions in adult tissues. C3G participates in regulating functions that require cytoskeletal remodelling such as adhesion, migration, maintenance of cell junctions, neurite growth and vesicle traffic. C3G is spatially and temporally regulated to act on Ras family GTPases Rap1, Rap2, R-Ras, TC21 and Rho family member TC10. Increased C3G protein levels are associated with differentiation of various cell types, indicating an important role for C3G in cellular differentiation. In signalling pathways, C3G serves functions dependent on catalytic activity as well as protein interaction and can therefore integrate signals necessary for the execution of more than one cellular function. This review summarizes our current knowledge of the biology of C3G with emphasis on its role as a transducer of signals to the actin cytoskeleton. Deregulated C3G may also contribute to pathogenesis of human disorders and therefore could be a potential therapeutic target.
Gamma-ray telescopes reveal powerful flares from the Crab Nebula
Authors: Schwarzschild Bertram M.
Published: March 2011

The brief, surprising flares involved synchrotron radiation from 1015-eV electrons. It’s hard to account for such rapid acceleration of charged particles to such enormous energies.
Time reversal produces optical focusing in scattering media
Authors: Smart Ashley G.
Published: March 2011

A technique hatched from concepts in acousto-optics and phase conjugation could be ideal for biomedical imaging and therapy.
Superconducting rings show hints of half-quantum vortices
Authors: Miller Johanna L.
Published: March 2011

To confirm a decades-old theoretical prediction, experimentalists have pushed the limits of mesoscopic sample manipulation and magnetization measurement.
Putting a new spin on quantum-dot qubits
Authors: Goss Levi Barbara
Published: March 2011

Researchers have shown that the electron spins of interest for quantum computation can be electrically controlled by spin–orbit coupling.
Obama calls for increased spending for electric vehicles and solar energy
Authors: Kramer David
Published: March 2011

Advanced batteries, high-risk energy research, and development of clean electricity would benefit from the plan outlined in the State of the Union address. The president sends Vice President Biden and other top officials out to sell that plan.
For underrepresented minorities, bridge programs ease transition to PhD studies
Authors: Matthews Jermey N. A.
Published: March 2011

Existing models for increasing the minuscule number of minority physics PhDs in the US include funding research experiences, forging university partnerships, and fostering a support network.
Acoustics of free-reed instruments
Authors: Cottingham James
Published: March 2011

Documents dating back to before 1000 BC describe a wind instrument whose reed vibrates back and forth across the frame that houses it. Nowadays, free-reed instruments inspire both scholarly study and musical innovation.
Politics of precision in ancient China
Authors: Crease Robert P.
Published: March 2011

Scholars have uncovered complex connections between metrology, musicology, and politics in the imperial courts of third-century China.
Dynamical fingerprints for probing individual relaxation processes in biomolecular dynamics with simulations and kinetic experiments
Authors: Noé Frank , Doose Sören , Daidone Isabella , Löllmann Marc , Sauer Markus , Chodera John D. , Smith Jeremy C.
Published: March 2011

There is a gap between kinetic experiment and simulation in their views of the dynamics of complex biomolecular systems. Whereas experiments typically reveal only a few readily discernible exponential relaxations, simulations often indicate complex multistate behavior. Here, a theoretical framework is presented that reconciles these two approaches. The central concept is “dynamical fingerprints” which contain peaks at the time scales of the dynamical processes involved with amplitudes determined by the experimental observable. Fingerprints can be generated from both experimental and simulation data, and their comparison by matching peaks permits assignment of structural changes present in the simulation to experimentally observed relaxation processes. The approach is applied here to a test case interpreting single molecule fluorescence correlation spectroscopy experiments on a set of fluorescent peptides with molecular dynamics simulations. The peptides exhibit complex kinetics shown to be consistent with the apparent simplicity of the experimental data. Moreover, the fingerprint approach can be used to design new experiments with site-specific labels that optimally probe specific dynamical processes in the molecule under investigation.
The country at a standstill: Yugoslavia and Slovene politics in the 1930s
Authors: Gašparič Jure
Published: March 2011

King Alexander's dictatorship in Yugoslavia (proclaimed in January 1929) was an expression of a real political need for consolidation in the country; however, in essence, it was an autocratic and repressive regime. More decisive moves toward a return of democracy did not occur, even later, after the replacement of his regime in June 1935. The political methods in the internal political life followed the pattern from the first half of the 1930s to the very eve of World War II. Such a situation also defined the relationship between the Slovenes and Yugoslavia. Slovene politics continued to look at the state from two angles – a unitary/centralist angle on the one hand and an autonomist/federalist angle on the other. Both camps (as well as other Yugoslav political players), however, failed to create an environment that would enable truly democratic compromises. The state was stuck at a “standstill,” but in spite of all its flaws, in the view of the Slovene political groups it represented the most suitable environment for the political and national life of Slovenes. Any serious political calculations that would go beyond this framework hardly existed.
Generation of zonal perturbations and transport barriers in plasmas
Authors: Militello F. , Romanelli M. , Connor J.W. , Hastie R.J.
Published: March 2011

It is shown that drift wave plasma turbulence in the electromagnetic regime can significantly affect the zonal flow dynamics and drive zonal fields. A new interpretation of the effect of the zonal fields on the zonal flow stability is given as previous analytic predictions are shown to be inadequate for accurately describing the numerical results. The zonal flow/field excitation mechanism in the electromagnetic regime can provide a possible explanation for the observed correlation between transport barrier formation and low shear rational surfaces in the plasma.
The strong effect of gaps on the required shaping of the ITER first wall
Authors: Stangeby Peter
Published: March 2011

Divertor tokamaks such as ITER also need limiters, namely for startup, rampdown, as well as protection of the main wall from normal and off-normal loads during the diverted phase. In future fusion devices the volume within the magnetic coils will be at a premium and it will be important to make the limiters as thin as possible. A continuous, or almost continuous, wall-limiter can be made thinner than a set of well spaced discrete limiters. The need to be able to remove and replace the components of a wall-limiter requires that its individual panels in fact be discrete but the gaps between the panels should be made as small as possible relative to the panel width to maximize the wall coverage and to minimize the extent of exposed panel edges. The modularity of a wall-limiter leads inevitably to misalignments. The gaps and misalignments reduce the power-handling capability of a modular wall-limiter relative to an ideal wall-limiter, i.e. one without any gaps or misalignments. It is shown that even small gaps and radial misalignments between the individual panels of a modular wall-limiter can require so much shaping, i.e. chamfering, of the panels in order to protect the panel edges that the peak deposited power flux density on the panel face considerably exceeds that for an ideal wall-limiter, typically by an order of magnitude. Nevertheless, compared with a set of discrete limiters which are separated by gaps larger than the limiter toroidal size, a modular, small-gap wall-limiter can still be thinner and can have lower peak deposited power flux densities (MW m−2), for a given total power load (MW).
Characteristics and control of the type I edge localized mode in JT-60U
Authors: Oyama N. , Hayashi N. , Aiba N. , Isayama A. , Urano H. , Sakamoto Y. , Kamada Y. , Takizuka T.
Published: March 2011

The detailed characteristics of the precursor of the type I edge localized mode (ELM) have been studied in JT-60U using diagnostics with high temporal and spatial resolution such as a microwave reflectometer, electron cyclotron emission (ECE) heterodyne radiometer and grating polychromator. Coherent density and temperature precursors have been observed before the collapse phase of type I ELM. The growth rate of the precursor is evaluated to be γ/ωA ∼ 10−3 for several edge pedestal conditions. From the phase delay between ECE signals measured at two toroidal locations and the frequency of the precursor, the toroidal mode number is experimentally evaluated as n = 8–10 or 14–16 assuming that the precursor rotates toroidally with the same toroidal rotation speed of carbon impurity. It is found that the dominant n varies with each ELM under the same plasma condition. The ratio of the pressure gradient inside the pedestal (∇p
in) to the pressure gradient within the pedestal (∇p
ped) has been confirmed as an important parameter in determining the ELM energy loss (ΔW
ELM) normalized to the pedestal stored energy (W
ped), ΔW
ELM/W
ped. From the comparison of the reduction rate in the ion temperature profile due to ELMs, a larger reduction rate within the pedestal and a wider ELM affected area are observed in the plasma with larger ∇p
in/∇p
ped. When the plasma near the top of the pedestal on the high-field side is heated by an electron cyclotron wave (ECW) power of 1.57 MW, the ΔW
ELM/W
ped is reduced by ∼35%, together with an increase in the ELM frequency. The increasing rate of the ELM frequency with the heating power is about four times larger in the ECW injection case than the natural power dependence observed in the neutral beam injection case.
ELM pacing investigations at JET with the new pellet launcher
Authors: Lang P.T. , Alonso A. , Alper B. , Belonohy E. , Boboc A. , Devaux S. , Eich T. , Frigione D. , Gál K. , Garzotti L. , Geraud A. , Kocsis G. , Köchl F. , Lackner K. , Loarte A. , Lomas P.J. , Maraschek M. , Müller H.W. , Neu R. , Neuhauser J. , Petravich G. , Saibene G. , Schweinzer J. , Thomsen H. , Tsalas M. , Wenninger R. , Zohm H.
Published: March 2011

A new pellet injection system was installed at JET designed for both fuelling and ELM pacing. The purpose of the pacing section was to validate pellet ELM pacing as a suitable tool for ELM mitigation in ITER. Pellet pacing was confirmed at the large size scale of JET. The dynamics of triggered ELMs was investigated with respect to their spontaneous counterparts. Triggered ELMs show features also typical for spontaneous ELMs in several operational regimes. Since none of these regimes was unsettled by the pellets this is a strong hint for compatibility with other plasma control tools. Observations and modelling results indicate the ELM triggering occurs by the evolution of the pellet ablation plasmoid into the first ELM filament followed by a poloidal spread of the instability. An ELM obviously can be forced by a pellet due to the strong local perturbation imposed already under unusual onset conditions but then evolves like any ELM typical for the corresponding plasma regime. For tool optimization the pellet mass and hence the convective confinement losses imposed have to be minimized. In our experiments, a lower mass threshold was observed for the first time. It has been found that to reliably trigger an ELM the pellet needs to be sufficiently large (and fast) to penetrate close to the pedestal top. Recent investigations are clear steps forward to validate the pellet pacing approach for ITER.
SurvJamda: an R package to predict patients' survival and risk assessment using joint analysis of microarray gene expression data
Authors: Yasrebi Haleh
Published: March 2011

Summary: SurvJamda (Survival prediction by joint analysis of microarray data) is an R package that utilizes joint analysis of microarray gene expression data to predict patients' survival and risk assessment. Joint analysis can be performed by merging datasets or meta-analysis to increase the sample size and to improve survival prognosis. The prognosis performance derived from the combined datasets can be assessed to determine which feature selection approach, joint analysis method and bias estimation provide the most robust prognosis for a given set of datasets.

Availability: The survJamda package is available at the Comprehensive R Archive Network, http://cran.r-project.org.

Contact:  hyasrebi@yahoo.com
Large-scale learning of combinatorial transcriptional dynamics from gene expression
Authors: Asif H. M. Shahzad , Sanguinetti Guido
Published: March 2011

Motivation: Knowledge of the activation patterns of transcription factors (TFs) is fundamental to elucidate the dynamics of gene regulation in response to environmental conditions. Direct experimental measurement of TFs' activities is, however, challenging, resulting in a need to develop statistical tools to infer TF activities from mRNA expression levels of target genes. Current models, however, neglect important features of transcriptional regulation; in particular, the combinatorial nature of regulation, which is fundamental for signal integration, is not accounted for.

Results: We present a novel method to infer combinatorial regulation of gene expression by multiple transcription factors in large-scale transcriptional regulatory networks. The method implements a factorial hidden Markov model with a non-linear likelihood to represent the interactions between the hidden transcription factors. We explore our model's performance on artificial datasets and demonstrate the applicability of our method on genome-wide scale for three expression datasets. The results obtained using our model are biologically coherent and provide a tool to explore the concealed nature of combinatorial transcriptional regulation.

Availability:  http://homepages.inf.ed.ac.uk/gsanguin/software.html.

Contact:  g.sanguinetti@ed.ac.uk

Supplementary information:  Supplementary data are available at Bioinformatics online.
Optimized Perioperative Analgesia Reduces Chronic Phantom Limb Pain Intensity, Prevalence, and Frequency
Authors: Karanikolas Menelaos , Aretha Diamanto , Tsolakis Ioannis , Monantera Georgia , Kiekkas Panagiotis , Papadoulas Spyros , Swarm Robert A. , Filos Kriton S.
Published: March 2011

Background

Severe preamputation pain is associated with phantom limb pain (PLP) development in limb amputees. We investigated whether optimized perioperative analgesia reduces PLP at 6-month follow-up.

Methods

A total of 65 patients underwent lower-limb amputation and were assigned to five analgesic regimens: (1) Epi/Epi/Epi patients received perioperative epidural analgesia and epidural anesthesia; (2) PCA/Epi/Epi patients received preoperative intravenous patient-controlled analgesia (PCA), postoperative epidural analgesia, and epidural anesthesia; (3) PCA/Epi/PCA patients received perioperative intravenous PCA and epidural anesthesia; (4) PCA/GA/PCA patients received perioperative intravenous PCA and general anesthesia (GA); (5) controls received conventional analgesia and GA. Epidural analgesia or intravenous PCA started 48 h preoperatively and continued 48 h postoperatively. The results of the visual analog scale and the McGill Pain Questionnaire were recorded perioperatively and at 1 and 6 months.

Results

At 6 months, median (minimum-maximum) PLP and P values (intervention groups vs. control group) for the visual analog scale were as follows: 0 (0-20) for Epi/Epi/Epi (P = 0.001), 0 (0-42) for PCA/Epi/Epi (P = 0.014), 20 (0-40) for PCA/Epi/PCA (P = 0.532), 0 (0-30) for PCA/GA/PCA (P = 0.008), and 20 (0-58) for controls. The values for the McGill Pain Questionnaire were as follows: 0 (0-7) for Epi/Epi/Epi (P < 0.001), 0 (0-9) for PCA/Epi/Epi (P = 0.003), 6 (0-11) for PCA/Epi/PCA (P = 0.208), 0 (0-9) for PCA/GA/PCA (P = 0.003), and 7 (0-15) for controls. At 6 months, PLP was present in 1 of 13 Epi/Epi/Epi, 4 of 13 PCA/Epi/Epi, and 3 of 13 PCA/GA/PCA patients versus 9 of 12 control patients (P = 0.001, P = 0.027, and P = 0.009, respectively). Residual limb pain at 6 months was insignificant.

Conclusions

Optimized epidural analgesia or intravenous PCA, starting 48 h preoperatively and continuing for 48 h postoperatively, decreases PLP at 6 months.
Conflicting preferences within females: sexual selection versus species recognition
Authors: Rosenthal Gil G. , Ryan Michael J.
Published: March 2011

Preferences for mates within and between species are often harmonious, as traits that females prefer are usually more developed in conspecifics than heterospecifics. This need not be the case, however. When it is not, conflict between these arenas of mate choice can be resolved if females attend to different cues for each task. But this raises the potential for correlations among preferences to limit the opportunity for these two processes to operate independently. Here, we show that, within individual female pygmy swordtails (Xiphophorus pygmaeus), directional preferences for conspicuous ornamentation are inversely associated with discrimination against a sympatric heterospecific,Xiphophorus cortezi. Thus, mate choice among and within species need not be separate, independent processes; instead, they can be mechanistically intertwined. As a consequence, different arenas of mate choice can constrain one another, even when females assess multiple cues.
Energetic inequivalence in eusocial insect colonies
Authors: DeLong John P.
Published: March 2011

The energetic equivalence rule states that population-level metabolic rate is independent of average body size. This rule has been both supported and refuted by allometric studies of abundance and individual metabolic rate, but no study, to my knowledge, has tested the rule with direct measurements of whole-population metabolic rate. Here, I find a positive scaling of whole-colony metabolic rate with body size for eusocial insects. Individual metabolic rates in these colonies scaled with body size more steeply than expected from laboratory studies on insects, while population size was independent of body size. Using consumer-resource models, I suggest that the colony-level metabolic rate scaling observed here may arise from a change in the scaling of individual metabolic rate resulting from a change in the body size dependence of mortality rates.
Too much of a good thing? Variety is confusing in mate choice
Authors: Lenton Alison P. , Francesconi Marco
Published: March 2011

Choice variety is supposed to increase the likelihood that a chooser's preferences are satisfied. To assess the effects of variety on real-world mate choice, we analysed human dating decisions across 84 speed-dating events (events in which people go on a series of sequential ‘mini-dates’). Results showed that choosers made
fewer
proposals (positive dating decisions) at events in which the available dates showed greater variety across such attributes as age, height, occupation and education, and this effect was particularly strong when choosers were confronted with a larger number of opposite-sex speed daters. Additionally, participants attending events in which the available options showed greater variety across these attributes were
less
likely to choose the consensually preferred mate option and
more
likely to choose no one at all. In contexts in which time is a limited resource, choice variety—rather than facilitating choice quality or increasing choosiness—is confusing and potentially detrimental to choice quality.
Capillary-based static self-assembly in higher organisms
Authors: Voise Jonathan , Schindler Michael , Casas Jérôme , Raphaël Elie
Published: March 2011

Organized structures produced by dynamic self-assembly are often observed in animal groups. Static self-assembly, however, has to date only been observed at the cellular and sub-cellular levels. The aim of this study was to analyse organized structures in immobile whirligig beetle groups on the water surface. We used theoretical and computational approaches to model the meniscus around whirligig beetles and to calculate the surface energy for configurations involving two beetles. Theoretical predictions were then tested using live insects and resin casts. Observations were also made for three and more casts. The meniscus of whirligig beetles had a bipolar shape with two concave parts. For two beetles, predicted configurations based on energy minima corresponded to beetles in contact by their extremities, forming lines and arrows, and agreed well with observations. Experimental results for three and more beetle casts revealed new geometrical arrangements similar to those obtained with colloids at interfaces. This study provides the first example of static self-assembly at the inter-organism level and shows the importance of capillary interactions in such formations. We identify the ecological context in which our findings are of relevance.
Comparative aerodynamic performance of flapping flight in two bat species using time-resolved wake visualization
Authors: Muijres Florian T. , Johansson L. Christoffer , Winter York , Hedenström Anders
Published: March 2011

Bats are unique among extant actively flying animals in having very flexible wings, controlled by multi-jointed fingers. This gives the potential for fine-tuned active control to optimize aerodynamic performance throughout the wingbeat and thus a more efficient flight. But how bat wing performance scales with size, morphology and ecology is not yet known. Here, we present time-resolved fluid wake data of two species of bats flying freely across a range of flight speeds using stereoscopic digital particle image velocimetry in a wind tunnel. From these data, we construct an average wake for each bat species and speed combination, which is used to estimate the flight forces throughout the wingbeat and resulting flight performance properties such as lift-to-drag ratio (L/D). The results show that the wake dynamics and flight performance of both bat species are similar, as was expected since both species operate at similar Reynolds numbers (Re) and Strouhal numbers (St). However, maximumL/Dis achieved at a significant higher flight speed for the larger, highly mobile and migratory bat species than for the smaller non-migratory species. Although the flight performance of these bats may depend on a range of morphological and ecological factors, the differences in optimal flight speeds between the species could at least partly be explained by differences in their movement ecology.
Cytokine production by primary human macrophages infected with highly pathogenic H5N1 or pandemic H1N1 2009 influenza viruses
Authors: Sakabe Saori , Iwatsuki-Horimoto Kiyoko , Takano Ryo , Nidom Chairul A. , Le Mai thi Quynh , Nagamura-Inoue Tokiko , Horimoto Taisuke , Yamashita Naohide , Kawaoka Yoshihiro
Published: March 2011

Highly pathogenic H5N1 avian influenza viruses have caused infection in humans, with a high mortality rate, since 1997. While the pathogenesis of this infection is not completely understood, hypercytokinaemia and alveolar macrophages are thought to play a role. To gain further insight into the cytokine-mediated pathogenesis of this infection in humans, we measured various cytokines produced by primary human macrophages infected with H5N1, pandemic H1N1 or seasonal influenza viruses. We found that many cytokines were produced at higher levels on infection with the H5N1 strains tested compared with seasonal influenza viruses. Interestingly, the extent of cytokine induction varied among the H5N1 strains and did not correlate with replicative ability in macrophages. Further, a pandemic H1N1 virus induced higher levels of several cytokines compared with seasonal viruses and some H5N1 strains. Our results demonstrate that high cytokine induction is not a universal feature of all H5N1 viruses.
PB1-mediated virulence attenuation of H5N1 influenza virus in mice is associated with PB2
Authors: Li Jing , Li Yongqiang , Hu Yi , Chang Guohui , Sun Wei , Yang Yinhui , Kang Xiaoping , Wu Xiaoyan , Zhu Qingyu
Published: March 2011

H5N1 avian influenza viruses demonstrate different phenotypes, such as pathogenicity after one or serial passages in mammalian hosts or cells. To establish the molecular basis of these phenotypes, we cloned isolates from the lungs of mice infected with human A/Vietnam/1194/2004 (H5N1) influenza virus. Large-plaque isolates were less pathogenic to mice than small-plaque isolates. Genome sequencing revealed that the small-plaque and large-plaque isolates differed in several amino acids. In order to assess their effects on pathogenicity in mice, two amino acid changes common to attenuated isolates, one in PB2 (I63T) and the other in PB1 (T677M), were inserted into a wild-type recombinant virus construct. The PB2 (I63T) or PB1 (T677M) mutations alone did not alter the phenotype of H5N1 virus, whereas recombinant virus with both mutations was less pathogenic than the wild-type recombinant virus. Furthermore, the PB1 (T677M) mutation showed a lower replication efficiency, although it had higher polymerase activity. The recombinant virus with the PB2 (63T) mutation replicated as well as the wild-type recombinant virus. These results suggest that the C terminus of PB1 of H5N1 influenza virus mediates virulence attenuation of H5N1 influenza virus in mice, associating with the N terminus of PB2. However, the role of the N terminus of PB2 in virulence attenuation in mice remains unclear.
Plating Cells for Microinjection: Figure 1.
Authors: Dean David A. , Gasiorowski Joshua Z.
Published: March 2011

INTRODUCTION

The efficient delivery of exogenous DNA to cells for expression and function studies is an essential technique of modern cell biology, and direct delivery of genetic material by microinjection remains a reliable means of transfection. This protocol describes the general procedures needed to culture cells for microinjection. Coverslips need to be marked so that microinjected cells can be identified at desired time points after injection. Coverslips can be etched by the user, as described here, or pre-etched coverslips can be purchased. Once the coverslips have been etched and sterilized, cells can be plated onto them and allowed to grow.
DNA Sample Preparation and Loading Sample into Pipettes for Microinjection of Cells
Authors: Dean David A. , Gasiorowski Joshua Z.
Published: March 2011

INTRODUCTION

The efficient delivery of exogenous DNA to cells for expression and function studies is an essential technique of modern cell biology, and direct delivery of genetic material by microinjection remains a reliable means of transfection. This protocol describes in general the preparation and loading of plasmid DNA for microinjections. Plasmid DNA can be purified by traditional means such as cesium chloride density ultracentrifugation, or by commercially available resin-based purification kits. The resulting preparation can then be delivered into microinjection needles either by backfilling or by a forward-filling approach.