bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolutionary analysis of HBV “S” antigen genetic diversity in Iranian blood donors: A nationwide study
Authors: Pourkarim Mahmoud Reza , Sharifi Zohre , Soleimani Ali , Amini‐Bavil‐Olyaee Samad , Elsadek Fakhr Ahmed , Sijmons Steven , Vercauteren Jurgen , Karimi Gharib , Lemey Philippe , Maes Piet , Alavian Seyed Moayed , Van Ranst Marc
Published: October 2013

The genetic diversity of the HBV S gene has a significant impact on the prophylaxis and treatment of hepatitis B infection. The effect of selective pressure on this genetic alteration has not yet been studied in Iranian blood donors. To explore HBV evolution and to analyze the effects and patterns of hepatitis B surface antigen (HBsAg) mutations on blood screening assays, 358 Iranian blood donors diagnosed as asymptomatic HBV carriers were enrolled in this nationwide study. Large S and partial S genes were amplified and sequenced. HBV (sub) genotypes and synonymous and nonsynonymous mutations were investigated. The impact of naturally occurring mutations on HBsAg ELISA results was explored. Phylogenetic analyses revealed that isolated strains were of genotype D. The dominant subgenotype/subtype was D1/ayw2. Deletions and naturally occurring stop codons in the pre‐S1 and major hydrophilic region (MHR) were identified. In total, 32.8% of the studied strains harbored 195 single or multiple mutations in the MHR, the majority of which were located at the first loop of the “a determinant” domain. The ayw2 subtype showed a significant effect on the ELISA signal/cut‐off value and carried fewer mutations in the MHR. Nonsynonymous/synonymous substitution value indicated that negative selection was the dominant evolutionary force in the HBV S gene. This nationwide study revealed that mutation frequency of HBsAg among Iranian blood donors was much higher than previous reports from the different local regions. These findings regarding the significant differences in reactivity of ELISA among different subtypes of HBV and its correlation with the number of mutations at the MHR will be valuable to public health authorities. J. Med. Virol. 86:144–155, 2014. © 2013 Wiley Periodicals, Inc.
Uvular injury during the perioperative period in patients undergoing general anesthesia
Authors: Pamnani Anup , Faggiani Susan L. , Hood Melanie , Kacker Ashutosh , Gadalla Farida
Published: October 2013

Objective

The purpose of this study was to evaluate the incidence and causes of uvular injury in the patients that received general anesthesia in the perioperative period.

Study Design

A 4‐year retrospective review of cases of uvular injury and their resolution was conducted in adult patients who received general anesthesia at our institution.

Methods

An extensive review was conducted of the quality assurance (QA) database maintained by the Department of Anesthesiology at our tertiary academic medical center. The database was searched for cases of uvular injury that occurred in adult patients undergoing general anesthesia that between January 2007 and December 2010. The medical records of identified patients were then obtained to evaluate the presentation, treatment and ultimate resolution of injury.

Results

Ten cases of uvular injury were reported in the 28,788 general anesthetics conducted over a 3‐year period in adult patients. This correlates to an incidence of 0.034%. Uvular injury occurred in mostly male patients (80%) during elective cases in the supine position. All cases were associated with endotracheal intubation. Additional objects, such as gastric tubes and esophageal temperature probes, were placed in the pharynx of 80% of these patients. Urologic procedures were associated with 50% of reported cases. Treatment ranged from observation to medical therapy. There were no permanent symptoms in any of the patients.

Conclusion

Uvular injury is a relatively rare complication that occurs in patients during the perioperative period who receive general anesthesia. While endotracheal intubation is closely associated with this type of injury, further study is required to elucidate the mechanism and other associated etiologic factors.

Level of Evidence

4. Laryngoscope, 124:196–200, 2014
Photocatalytic degradation of C.I. Acid Orange 7 by TiO2 nanoparticles immobilized onto/into chitosan‐based hydrogel
Authors: Marija Lučić , Nedeljko Milosavljević , Maja Radetić , Zoran Šaponjić , Marija Radoičić , Melina Kalagasidis Krušić
Published: October 2013

Photocatalytic degradation of dye C.I. Acid Orange 7 in aqueous solution using TiO2/hydrogel nanocomposite under solar light simulating source was studied. Hydrogel based on chitosan, itaconic and methacrylic acid was modified with colloidal TiO2 nanoparticles synthetized by acidic hydrolysis of TiCl4 and commercial Degussa P25 TiO2 nanoparticles. SEM/EDX analysis confirmed the presence of TiO2 nanoparticles onto/into hydrogel. It was found that both types of photocatalysts efficiently removed the dye from solution, but sorption rates and photodegradation efficiency were higher in the case of colloidal TiO2 nanoparticles. They ensured complete discoloration of dye solution. The efficiency of the reused TiO2/hydrogel nanocomposite showed that photodegradation activity was maintained at satisfactory level after three repeated cycles of illumination. POLYM. COMPOS., 35:806–815, 2014. © 2013 Society of Plastics Engineers
5α‐reductase type 3 enzyme in benign and malignant prostate
Authors: Titus Mark A. , Li Yun , Kozyreva Olga G. , Maher Varun , Godoy Alejandro , Smith Gary J. , Mohler James L.
Published: October 2013

BACKGROUND

Currently available 5α‐reductase inhibitors are not completely effective for treatment of benign prostate enlargement, prevention of prostate cancer (CaP), or treatment of advanced castration‐recurrent (CR) CaP. We tested the hypothesis that a novel 5α‐reductase, 5α‐reductase‐3, contributes to residual androgen metabolism, especially in CR‐CaP.

METHODS

A new protein with potential 5α‐reducing activity was expressed in CHO‐K1 cellsandTOP10 E. coli for characterization. Protein lysates and total mRNA were isolated from preclinical and clinical tissues. Androgen metabolism was assessed using androgen precursors and thin layer chromatography or liquid chromatography tandem mass spectrometry.

RESULTS

The relative mRNA expression for the three 5α‐reductase enzymes in clinical samples of CR‐CaP was 5α‐reductase‐3 ≫ 5α‐reductase‐1 > 5α‐reductase‐2. Recombinant 5α‐reductase‐3 protein incubations converted testosterone, 4‐androstene‐3,17‐dione (androstenedione) and 4‐pregnene‐3,20‐dione (progesterone) to dihydrotestosterone, 5α‐androstan‐3,17‐dione, and 5α‐pregnan‐3,20‐dione, respectively. 5α‐Reduced androgen metabolites were measurable in lysates from androgen‐stimulated (AS) CWR22 and CR‐CWR22 tumors and clinical specimens of AS‐CaP and CR‐CaP pre‐incubated with dutasteride (a bi‐specific inhibitor of 5α‐reductase‐1 and 2).

CONCLUSION

Human prostate tissues contain a third 5α‐reductase that was inhibited poorly by dutasteride at high androgen substrate concentration in vitro, and it may promote DHT formation in vivo, through alternative androgen metabolism pathways when testosterone levels are low. Prostate 74:235–249, 2014. © 2013 Wiley Periodicals, Inc.
Bridging vs. Chelating Coordination Modes of Vinylsilanes in CuI π‐Complexes: Structure and Stability
Authors: Dużak Tomasz , Zarychta Bartosz , Olijnyk Volodymyr
Published: October 2013

Two new copper(I) olefin complexes, [Cu6Cl6(MTrVS)2] (1) and [Cu2Cl2(DMVSP)2] (2), of tridentate bridging methyltrivinylsilane (MTrVS) and bidentate chelating 2‐[dimethyl(vinyl)silyl]pyridine (DMVSP) have been synthesized and characterized by single‐crystal X‐ray structure analysis, IR and 1H NMR spectroscopy. It has been shown that using the alkenylsilanes with required electronic properties, molecular symmetry and conformational flexibility, it is possible to control the formation of optimal copper(I) halide oligomers. The obtained results, together with relevant literature data, also illustrate how the coordination mode of vinylsilanes is related to Cu–(C=C) bond strengthening and, consequently, to stability of the organometallic compounds. In particular, we suggest that, together with Cu–Cα distance shortening accompanied by a segmentation of π‐conjugated chelate ring, complex shows an increased lability to form probably an alkenylcopper intermediate in the homocoupling reaction of alkenyl(2‐pyridyl)silanes. At the same time, no appreciable reduction of thermal stability of π‐conjugated chelate complex 2 with respect to bridged compound 1 emerges.
Hidden burrow plugs and their function in the tiger beetle, Cosmodela batesi (Coleoptera, Cicindelidae)
Authors: Lin Shou-Wang , Okuyama Toshinori
Published: October 2013

Tiger beetle larvae excavate and live in underground burrows, whose openings they sometimes plug with soil. This study documents the burrow plugging behavior of the tiger beetle, Cosmodela batesi (Fleutiaux), in the field. We also tested the function of burrow plugs in the laboratory. In the field, C. batesi more frequently made a plug when it rained. Most larvae made plugs inside their burrows (rather than at the soil surface), and the use of an endoscope was necessary to detect these sub-surface plugs. In the laboratory, flooding was simulated by artificially introducing water into specially-made arenas. Water filled the entire burrow when there was no plug, whereas plugged burrows maintained air chambers inside. When a plug was broken with a wire, burrows filled up with water. The burrowing and plugging behavior described in this study is likely an important adaptation of C. batesi to its habitat.
Mirror-symmetric exact coherent states in plane Poiseuille flow
Authors: Nagata M. , Deguchi K.
Published: October 2013

Two new families of exact coherent states are found in plane Poiseuille flow. They are obtained from the stationary and the travelling-wave mirror-symmetric solutions in plane Couette flow by a homotopy continuation. They are characterized by the mirror symmetry inherited from those continued solutions in plane Couette flow. The first family arises from a saddle-node bifurcation and the second family bifurcates by breaking the top–bottom symmetry of the first family. We find that both families exist below the minimum saddle-node-point Reynolds number known to date (Waleffe, Phys. Fluids, vol. 15, 2003, pp. 1517–1534).
Fragmented Liberalization in the Chinese Automotive Industry: The Political Logic behind Beijing Hyundai's Success in the Chinese Market
Authors: Oh Seung-Youn
Published: October 2013

This paper explains the extraordinary rise of the Beijing Hyundai Motor Company (BHMC), a joint venture between a state-owned enterprise run by the Beijing municipal government and Hyundai Motor Company. Within the span of three years, the BHMC soared to become China's second-ranked automotive manufacturer in terms of units sold. I highlight the role of the Beijing municipal government in creating favourable market conditions for the BHMC during its initial operation phase (2002–2005). The Beijing municipal government selectively adopted protectionist measures and liberalizing measures to promote its locally based company. I characterize this practice asfragmented liberalization,a system through which sub-national governments discriminately apply WTO or central government regulations to promote their local joint venture partner. In so doing, I also challenge the existing assumption that multinational companies are the drivers of economic liberalization, by showing Hyundai's support for local protectionism and industrial policy at the sub-national level.
A consistent semantics of self-adjusting computation
Authors: ACAR UMUT A. , BLUME MATTHIAS , DONHAM JACOB
Published: October 2013

This paper presents a semantics of self-adjusting computation and proves that the semantics is correct and consistent. The semantics introduces memoizing change propagation, which enhances change propagation with the classic idea of memoization to enable reuse of computations even when memory is mutated via side effects. During evaluation, computation reuse via memoization triggers a change-propagation algorithm that adapts the reused computation to the memory mutations (side effects) that took place since the creation of the computation. Since the semantics includes both memoization and change propagation, it involves both non-determinism (due to memoization) and mutation (due to change propagation). Our consistency theorem states that the non-determinism is not harmful: any two evaluations of the same program starting at the same state yield the same result. Our correctness theorem states that mutation is not harmful: Self-adjusting programs are compatible with purely functional programming. We formalize the semantics and its meta-theory in the LF logical framework and machine check our proofs using Twelf.
The Impact of Heat Waves on Transport Volumes in an Urban Emergency Medical Services System: A Retrospective Review
Authors: Kue Ricky C. , Dyer K. Sophia
Published: October 2013

Introduction

Heat waves pose a serious public health risk to particular patient populations, especially in urban areas. Emergency Medical Services (EMS) in many urban areas constitute the first line of regional preparation and response to major heat wave events; however, little is known on heat wave operational impact to the EMS system, such as call volume or demand.

Objective

To examine the effect of heat wave periods on overall urban EMS system call volume and transport volume as well as the nature of the call types.

Methods

Retrospective review of all emergency medical calls to an urban, two-tiered EMS system performed over a 5-year period from 2006–2010. Heat wave days (HWD) defined as two or more consecutive days of hot weather >32.2°C (90°F) were compared with similar non-heat wave days (nHWD) of the previous year to also include two calendar days prior to and after the heat wave. National Weather Service (NWS) temperature data, daily EMS call volume data, and call type codes were collected and underwent descriptive analysis.

Results

Thirty-one HWD were identified and compared with 93 nHWD. The mean maximum temperature for HWD was 34°C (93.2°F) compared with 25.3°C (77.6°F) for nHWD (P< .001). Average daily medical emergency calls (318.4 vs 296.3,P< .001) and actual patients transported per day (247.5 vs 198.3,P< .001) were significantly higher during HWD. There was no difference in daily medical emergency call volume or EMS transports between weekdays or weekend days. No significant differences on various call types were observed between HWD and nHWD except for “heat” related calls (7.7 vs 0.5,P< .001).

Conclusion

Emergency Medical Services call volumes were significantly increased during heat waves, however there was minimal change in the types of calls received.

KueRC,DyerKS.The impact of heat waves on transport volumes in an urban Emergency Medical Services system: a retrospective review.Prehosp Disaster Med.2013;28(6):1-6.
Market integration and natural resource use in developing countries: a linked agrarian-resource economy in Northern Honduras
Authors: Manning Dale T. , Taylor J. Edward , Wilen James E.
Published: October 2013

Most resource management studies model the resource in isolation from the rest of the economy of which it is part. In many developing economies, agents participate in multiple activities, creating linkages between resource exploitation and other sectors (e.g., agriculture). In Northern Honduran fishing communities, households allocate effort to fishing according to the opportunity cost of their time, which depends on returns in other activities. We develop a model that demonstrates how market structure impacts fishery exploitation. Agricultural price increases have an ambiguous effect on labor allocated to fishing because they reduce the value of labor in fishing but increase the demand for fish via an income effect. The size and magnitude of impacts depend strongly on the tradability of inputs and outputs in the community economy. The findings point to a need to account for economic linkages and market structure when designing policies to reduce pressure on a natural resource.
Endogenous longevity and the joint dynamics of pollution and capital accumulation
Authors: Varvarigos Dimitrios
Published: October 2013

The current paper offers a new explanation of the emergence of multiple equilibria, for which the high (low) income equilibrium is associated with high (low) environmental quality. This new explanation rests on endogenous technological choice in the presence of emission taxes – an idea whose foundations find strong support from existing empirical evidence. Thus, the interactions between environmental policy and technology choice, within a framework that accounts for the health effects of pollution, may suggest a possible mechanism behind some of the observed differences in income, life expectancy and environmental quality among countries.
Does it pay to delay social security?
Authors: SHOVEN JOHN B. , SLAVOV SITA NATARAJ
Published: October 2013

Social Security benefits may be commenced at any time between ages 62 and 70. As individuals who claim later can, on average, expect to receive benefits for a shorter period, an actuarial adjustment is made to the monthly benefit to reflect the age at which benefits are claimed. We investigate the actuarial fairness of that adjustment in light of recent improvements in mortality and historically low interest rates. We show that delaying is actuarially advantageous for a large number of people, even for individuals with mortality rates that are twice the average. At real interest rates closer to their historical average, singles with mortality that is substantially greater than average do not benefit from delay, although primary earners with high mortality can still improve the present value of the household's benefits through delay. We also investigate the extent to which the actuarial advantage of delay has grown since the early 1960s, when the choice of when to claim first became available, and we decompose this growth into three effects: (1) the effect of changes in Social Security's rules, (2) the effect of changes in the real interest rate, and (3) the effect of changes in life expectancy. Finally, we quantify the extent to which the gains from delay can be expected to increase in the future as a result of mortality improvements.
The impact of the economic crisis on media framing: evidence from three elections in Ireland
Authors: O’Malley Eoin , Brandenburg Heinz , Flynn Roddy , McMenamin Iain , Rafter Kevin
Published: October 2013

Media coverage of elections in Europe and North America has increasingly focused on the campaign as a game rather than a policy debate. This is often explained by the changes in media pressures. It may also reflect the narrowing of policy space between left and right and the comparative prosperity enjoyed in Europe and North America. But the relevance of policy varies. The global economic crisis might have led to an increased interest in policy among voters and focus on it by media. Ireland experienced both extremes of boom and crisis between the late 1990s and 2011. The Irish case allows us to test the impact of the crisis on media framing of elections. This article uses original data from the three most recent national elections in Ireland, with a research design that holds other pertinent variables constant. We find empirical support for the theoretical expectation that the context of the election affects the relative focus on campaign or horserace vs. substantive policy issues.
Follicular T‐helper cells: controlled localization and cellular interactions
Authors: Qi Hai , Chen Xin , Chu Coco , Lu Peiwen , Xu Heping , Yan Jiacong
Published: October 2013

Affinity‐matured, isotype‐switched antibodies afford humoral protection against microbial infections. Cells capable of producing such antibodies are derived from the germinal center (GC) formed during a T‐dependent B‐cell response. Follicular T‐helper (TFH) cells are a recently defined subset of CD4 T cells that are specialized in promoting the B‐cell response and GC reaction. These cells exhibit a CXCR5+ICOShiPD‐1hi surface phenotype, express a high level of transcriptional repressor Bcl‐6 and possess a unique ability to reside in the GC. Insights into how TFH cells develop and function promise to refine our strategies toward more effective antibody‐based vaccines and therapies for humoral autoimmunity. In this review, we summarize the current understanding of how TFH‐associated molecules regulate dynamic localization and B‐cell‐interacting properties of these cells, as both aspects are at the core of being TFH cells.
Sequestration of Martian CO2 by mineral carbonation
Authors: Tomkinson Tim , Lee Martin R. , Mark Darren F. , Smith Caroline L.
Published: October 2013

Carbonation is the water-mediated replacement of silicate minerals, such as olivine, by carbonate, and is commonplace in the Earth’s crust. This reaction can remove significant quantities of CO2 from the atmosphere and store it over geological timescales. Here we present the first direct evidence for CO2 sequestration and storage on Mars by mineral carbonation. Electron beam imaging and analysis show that olivine and a plagioclase feldspar-rich mesostasis in the Lafayette meteorite have been replaced by carbonate. The susceptibility of olivine to replacement was enhanced by the presence of smectite veins along which CO2-rich fluids gained access to grain interiors. Lafayette was partially carbonated during the Amazonian, when liquid water was available intermittently and atmospheric CO2 concentrations were close to their present-day values. Earlier in Mars’ history, when the planet had a much thicker atmosphere and an active hydrosphere, carbonation is likely to have been an effective mechanism for sequestration of CO2.
Characterization of the magnesium chelatase from Thermosynechococcus elongatus
Authors: Adams Nathan B. P. , Marklew Christopher J. , Brindley Amanda A. , Hunter C. Neil , Reid James D.
Published: October 2013

The first committed step in chlorophyll biosynthesis is catalysed by magnesium chelatase (E.C. 6.6.1.1), which uses the free energy of ATP hydrolysis to insert an Mg2+ ion into the ring of protoporphyrin IX. We have characterized magnesium chelatase from the thermophilic cyanobacterium Thermosynechococcus elongatus. This chelatase is thermostable, with subunit melting temperatures between 55 and 63°C and optimal activity at 50°C. The T. elongatus chelatase (kcat of 0.16 μM/min) shows a Michaelis–Menten-type response to both Mg2+ (Km of 2.3 mM) and MgATP2− (Km of 0.8 mM). The response to porphyrin is more complex; porphyrin inhibits at high concentrations of ChlH, but when the concentration of ChlH is comparable with the other two subunits the response is of a Michaelis–Menten type (at 0.4 μM ChlH, Km is 0.2 μM). Hybrid magnesium chelatases containing a mixture of subunits from the mesophilic Synechocystis and Thermosynechococcus enzymes are active. We generated all six possible hybrid magnesium chelatases; the hybrid chelatase containing Thermosynechococcus ChlD and Synechocystis ChlI and ChlH is not co-operative towards Mg2+, in contrast with the Synechocystis magnesium chelatase. This loss of co-operativity reveals the significant regulatory role of Synechocystis ChlD.
Programming style: An example
Authors: Welch L. C.
Published: October 2013

The relationship of programming style and ‘‘quality of software’’ is discussed. The quality of software is defined not only in objective terms, such as whether or not the answers are correct and the speed with which they are produced, but also in more subjective terms such as maintainability and readabilty. Examples in FORTRAN and C illustrate how stylistic features can improve software quality.
PBAR: A code for calculating the electromagnetic contribution to the energy levels of antiprotonic atoms
Authors: Borie E. , Jödicke B.
Published: October 2013

This article describes briefly the physical effects contributing to the energy levels of antiprotonic atoms and provides a description of a code PBAR that has been written to calculate the electromagnetic contribution.
Two-dimensional calculations using one-dimensional arrays, or ‘‘Life on the Skew’’
Authors: Siegman Anthony E.
Published: October 2013

Two-dimensional problems with periodic boundary conditions can be reprogrammed as one-dimensional arrays with no special handling of array indices at boundary edges or corners being required. The result is physically equivalent to a kind of vertically skewed periodic boundary condition.
An interactive, discipline-independent data visualization system
Authors: Treinish Lloyd A.
Published: October 2013

Critical to the understanding of data is the ability to provide pictorial or visual representations of that data. Given the ability to access data via an appropriate, easy-to-use interface, a researcher must employ tools to visualize data as one important mechanism in the data analysis process. Visualization, then, is a method of computing that gives visual form to complex data utilizing graphics and imaging technology. To support correlative data analysis (i.e., working with data from a variety of sources to study a problem of scientific interest), there is an obvious focus on generic visualization via the development of discipline-independent visualization techniques. The NSSDC (National Space Science Data Center) Graphics System (NGS) has been developed to provide an interactive discipline-independent toolbox for nonprogrammers to achieve such visualization of data. The NGS supports displays of any arbitrary multidimensional subset of any data set by providing a large variety of different representation schemes, all of which are supported by implicit animation (i.e., slicing of a data set into sequences). In addition, the design of the NGS provides an open-ended framework for data visualization, so that new capabilities can be added. New tools have been implemented as a result of NSSDC’s research in several areas of computer science, including novel computer graphics rendering techniques and data structures.
Plotting of closed field lines with an application to coherently excited atoms
Authors: Westerveld W. B.
Published: October 2013

The problem of plotting closed field lines is considered. To achieve fast and accurate plotting, the local curvature of the field lines must be taken into account. A simple formalism is presented that allows a high degree of precision to be achieved, as demonstrated for the case of a circular field line. Plots of the electronic charge and electronic current distribution of a partially coherent H(n=3) atom are shown as examples.
An adaptive data-smoothing routine
Authors: Taylor Clayborne D. , Nicolas David P.
Published: October 2013

An adaptive noise reduction algorithm that can be implemented on a microcomputer is developed. The routine may be applied to any smooth signal with additive random noise.
Simulation of an antiferromagnet by microcomputer
Authors: Yamazaki M. , Murai Y.
Published: October 2013

Computer simulation of the behavior of the system, of which free energy is known to depend on a number of parameters and also on a running parameter, is exhibited. As an example, the induced magnetization of a uniaxial antiferromagnet under varying external field is shown. It has three phases: antiferromagnetic, spin-flopping, and ferromagnetic. Though the complexity of the expression of free energy makes it difficult to see when and how phase transition occurs, a simple device facilitates visualization of the processes.
Efficient random walk algorithm for computing conductivity in continuum percolation systems
Authors: Tobochnik Jan
Published: October 2013

Random walks can be used to obtain the diffusion constant and thus the conductivity for continuum percolation problems. This paper presents an efficient algorithm that allows walkers to move very large distances in one step. The algorithm uses a first-passage time distribution for d-dimensional spherical surfaces. Results are given for overlapping nonconducting disks in two dimensions. Depending on the density of disks, it is found that the present algorithm is about 5 to 50 times faster than an equivalent algorithm using fixed step lengths.
Simulation of the magnetization-reversal dynamics on the Connection Machine
Authors: Mansuripur Masud , Giles Roscoe
Published: October 2013

Large two-dimensional lattices of interacting magnetic dipoles representing thin films of amorphous rare-earth–transition-metal alloys are studied on the Connection Machine. The accuracy of the results is established by comparing the simulated dynamics of isolated Bloch walls with theoretical predictions. The effects of random axis anisotropy on the process of magnetization reversal are then investigated, and the nucleation and growth of reverse-magnetized domains are found to be the mechanism of reversal. The obtained hysteresis loops have very high squareness, and sample coercivities are well within the range of experimental values.
CHAOS: A SUN-based program for analyzing chaotic systems
Authors: Aronson J. W.
Published: October 2013

CHAOS is a C-based program on SUN workstations, designed for studying nonlinear dynamics. It furnishes easy access to graphical and numerical procedures through the SUN windowing system. Among the graphical tools of CHAOS are the drawing of basins, basin boundaries, bifurcation diagrams, unstable manifolds, and point sets. The program can plot in 2D and 3D as well as on the surface of a cylinder, sphere, or torus. On the numerical side, CHAOS can compute fractal and correlation dimensions, Lyapunov exponents, Poincaré maps, power spectra, and periodic orbits. The program allows for the quick and easy addition of new systems of equations.
The Comprehensive Unified Physics Learning Environment: Part I. Background and System Operation
Authors: Wilson Jack M. , Redish Edward F.
Published: October 2013

The CUPLE consortium, which has the support of the IBM Corporation, the Annenberg/CPB project, and the American Association of Physics Teachers, has produced the prototype of a new instructional resource for college and university physics courses. The Comprehensive Unified Physics Learning Environment (CUPLE) combines flexible computer-based tools with inputs from laboratory experiments, video recordings, and other sources. This two-part report discusses motivations for, and implementations of, the CUPLE concepts. In Part I, the authors describe the context for curriculum reform, the choices of hardware and software platforms, and operation of the system. Part II, of this report will appear in the next issue. It describes the modular text materials, student programming, the linkage with laboratory experiments, the use of video tools, and the open system environment.
The Comprehensive Unified Physics Learning Environment: Part II. The Basis for Integrated Studies
Authors: Wilson Jack M. , Redish Edward F. , Donnelly Denis
Published: October 2013

The CUPLE consortium, which has the support of the IBM Corporation, the Annenberg/CPB project, and the American Association of Physics Teachers, has produced the prototype of a new instructional resource for college and university physics courses. The Comprehensive Unified Physics Learning Environment (CUPLE) combines flexible computer-based tools with inputs from laboratory experiments, video recordings, and other sources. This two-part report discusses motivations for, and implementations of, the CUPLE concepts. Part I of this report appeared in the previous issue, and described the context for curriculum reform, the choices of hardware and software platforms, and operation of the system. In Part II, the authors describe the modular text materials, student programming, the linkage with laboratory experiments, the use of video tools, and the open system environment.
Early-life stress has persistent effects on amygdala function and development in mice and humans
Authors: Malter Cohen Matthew , Jing Deqiang , Yang Rui R. , Tottenham Nim , Lee Francis S. , Casey B. J.
Published: October 2013

Significance

The current study provides evidence of early and persistent alterations in anxious behavior and amygdala function following the early-life stress of disorganized parental care. These changes in both brain and behavior are not diminished when the stressor is removed nor diminished with the development of prefrontal regulatory regions. The findings underscore the importance of early-life experiences on later development and highlight the need for early intervention for populations at-risk following early-life stressors.
Ferrous iron-dependent drug delivery enables controlled and selective release of therapeutic agents in vivo
Authors: Deu Edgar , Chen Ingrid T. , Lauterwasser Erica M. W. , Valderramos Juan , Li Hao , Edgington Laura E. , Renslo Adam R. , Bogyo Matthew
Published: October 2013

Significance

Selective drug delivery to diseased tissue is a promising approach to mitigate drug-related side effects while improving efficacy. This concept has been demonstrated in the case of photodynamic therapy, where activation of cytotoxic drugs at the tumor site provides a clear advantage compared with traditional chemotherapy. Here, we exploit the aberrantly high levels of mobile ferrous iron produced during the blood stage of malaria to selectively deliver a drug species to the parasite. The result is improved on-target vs. off-target action of the drug species and greater drug tolerability and efficacy. This approach should be applicable to other disease states associated with aberrant levels of ferrous iron.
Structural and biological studies on bacterial nitric oxide synthase inhibitors
Authors: Holden Jeffrey K. , Li Huiying , Jing Qing , Kang Soosung , Richo Jerry , Silverman Richard B. , Poulos Thomas L.
Published: October 2013

Significance

Nitric oxide (NO) produced by bacterial nitric oxide synthase has recently been shown to protect the Gram-positive pathogens
Bacillus anthracis
and
Staphylococcus aureus
from antibiotics and oxidative stress. Using
Bacillus subtilis
as a model system, we identified two NOS inhibitors that work in conjunction with an antibiotic to kill
B. subtilis
. Moreover, comparison of inhibitor-bound crystal structures between the bacterial NOS and mammalian NOS revealed an unprecedented mode of binding to the bacterial NOS that can be further exploited for future structure-based drug design. Overall, this work is an important advance in developing inhibitors against gram-positive pathogens.
Recognition of synthetic glycopeptides by HIV-1 broadly neutralizing antibodies and their unmutated ancestors
Authors: Alam S. Munir , Dennison S. Moses , Aussedat Baptiste , Vohra Yusuf , Park Peter K. , Fernández-Tejada Alberto , Stewart Shelley , Jaeger Frederick H. , Anasti Kara , Blinn Julie H. , Kepler Thomas B. , Bonsignori Mattia , Liao Hua-Xin , Sodroski Joseph G. , Danishefsky Samuel J. , Haynes Barton F.
Published: October 2013

Significance

A current key goal of HIV-1 vaccine development is to learn how to induce antibodies that will neutralize many diverse HIV-1 strains. Current HIV-1 vaccines elicit strain-specific neutralizing antibodies, whereas broadly neutralizing antibodies (BnAbs) are not induced and only arise in select HIV-1 chronically infected individuals. One strategy for induction of favored antibody responses is to design and produce homogeneous immunogens with selective expression of BnAb but not dominant epitopes. In this study, we describe the binding properties of chemically synthesized variable loop 1/2 (V1V2) glycopeptides that bind both to mature HIV-1 envelope BnAbs and the receptors of their naïve B cells. These results demonstrate that such synthetic glycopeptides can be immunogens that selectively target BnAb naïve B cells.
High-throughput imaging of neuronal activity in
Caenorhabditis elegans
Authors: Larsch Johannes , Ventimiglia Donovan , Bargmann Cornelia I. , Albrecht Dirk R.
Published: October 2013

Significance

Most behaviors and neuronal responses are variable across individual animals and repeated presentation of the same stimulus. Current neuronal recording techniques examine one animal at a time, whereas hundreds to thousands of trials may be necessary to understand the probability and range of responses. We developed an imaging system to record neuronal activity, detected by genetically encoded calcium indicators, simultaneously from 20
Caenorhabditis elegans
animals in microfluidic arenas. We used this system to characterize chemosensory neuron responses to odors and pharmacological manipulation. The system allowed recordings in freely moving animals, whose neuronal responses could be correlated with behavior. We found that behavioral variability is observed even when sensory responses are reproducible, and that sensitivity to specific odors varies among individual animals.
3-(1,3-Diphenylpropan-2-yl)-4-methyl-6-phenylisoxazolo[3,4-d]pyridazin-7(6H)-one
Authors: Campana Charles F. , Mirzaei Joseph , Koerner Chris , Gates Christina , Natale Nicholas R.
Published: October 2013

In the title compound, C27H23N3O2, the geminal benzyl groups branching out from the methine adjacent to the isoxazole group are bothsyn-oriented to the methyl group of the pyridazinone moiety, as reflected by C—C distances of 3.812 (2) and 4.369 (2) Å between the methyl carbon and the nearest ring carbon of each benzyl group. This kind of conformation is retained in CDCl3solution, as evidenced by distinct phenyl-shielding effects on the1H NMR signals of the methyl H atoms. The isoxazolo[3,4-d]pyridazin ring system is virtually planar (r.m.s. deviation from planarity = 0.031 Å), but the N-bonded phenyl group is inclined to the former by an ring–ring angle of 55.05 (3)°. In the crystal, the T-shaped molecules are arranged in an interlocked fashion, forming rod-like assemblies along [10-1]. The molecules are held together by unremarkable weak C—H...N, C—H...O and C—H...π interactions (C—O,N,C > 3.4 A), while significant π–π-stacking interactions are absent.
Poly[[(μ2-benzene-1,3-dicarboxylato){μ2-1,4-bis[(1H-imidazol-1-yl)methyl]benzene}cadmium] dimethylformamide monosolvate]
Authors: Chen Yan , Wang Daguang , He Liang , Li Wei , Suo Jian
Published: October 2013

The title coordination polymer, {[Cd(C8H4O4)(C14H14N4)]·C3H7NO}n, was synthesized by solvothermal reaction of metallic cadmium with the semi-rigid neutral ligand 1,4-bis[(1H-imidazol-1-yl)methyl]benzene (bix) and the V-shaped benzene-1,3-dicarboxylic acid (m-H2bdc). The structure exhibits a pseudo-C-centring which is almost fulfilled by the polymeric metal complex but not by the solvent dimethylformamide (DMF) molecules. The asymmetric unit contains two independent CdIIions, twom-bdc2−ligands, one and two half bix ligands, and two solvent DMF molecules. The CdIIions are both five-coordinated by three O atoms from two differentm-bdc2−ligands and two N atoms from two different bix ligands in a distorted square-pyramidal geometry. Them-bdc2−ligands adopt a chelate-monodentate coordination mode, connecting neighboring CdIIions into a zigzag chain parallel to [110]. Adjacent chains are further cross-linked by bix ligands, giving rise to a puckered sheet nearly perpendicular to the chain direction. Thus, each CdIIion is connected to four neighboring CdIIions through twom-bdc2−anions and two bix ligands, giving rise to the final non-interpenetrating uninodal layer with sql (4,4) topology.
4-Methyl-N-(4-nitrobenzylidene)piperazin-1-amine
Authors: Kavitha Channappa N. , Jasinski Jerry P. , Anderson Brian J. , Yathirajan H.S. , Kaur Manpreet
Published: October 2013

In the title compound, C12H16N4O2, the piperazine ring is in a slightly distorted chair conformation. In the molecule, the mean plane of the nitro group is twisted by 8.0 (3)° from that of the benzene ring. Also, the mean plane of the 2-nitrobenzyl ring is twisted slightly from that of the piperazine ring, with an N—N=C—C torsion angle of −176.24 (11)°. In the crystal, pairs of weak C—H...O interactions link the molecules into dimers approximately along [010].
1-(4-Chlorophenyl)-3-(3-chloropropionyl)thiourea
Authors: Yamin Bohari M. , Soh Siti K. C. , Yusoff Siti Fairus M.
Published: October 2013

In the title compound, C10H10Cl2N2OS, the molecule adopts atrans–cisconformation with respect to the position of the carbonyl group and the chlorophenyl groups relative to the thiono group across the C—N bonds. The molecule is stabilized by an N—H...O hydrogen bond. In the crystal, molecules are linked by N—H...S and C—H...O hydrogen bonds, forming zigzag chains along theb-axis direction. C—H...π interactions are also present.
The influence of fabric air permeability on the efficacy of ventilation features
Authors: Patrick Morrissey Matthew , Michel Rossi René
Published: October 2013

Purpose

– The purpose of this investigation was to measure the changes in effective thermal insulation caused by three different types of outer garment ventilation features (chest zips, back zips and pit zips) when combined with either a high or low air permeability insulating layer.

Design/methodology/approach

– The measurements in this investigation were made with a thermal manikin and with a 26 zone thermal torso. Measurements were made at two air flow speeds with each manikin; the different air flow characteristics for each manikin allowed investigation of how ventilation features interact with different air flow distributions.

Findings

– It was established in this study that high permeability insulation increases the efficacy of ventilation features by an average of 7 per cent at the low wind speed and 10 per cent at the high wind speed. No particular ventilation feature was found to be consistently the most effective; the data suggest that garment openings should simply be located in well-ventilated areas.

Originality/value

– This investigation analysed the ventilation characteristics of protective clothing ensembles with different ventilation features, allowing designers to create more comfortable clothing for work and leisure activities.
Considering business start-up in recession time
Authors: Nabi Ghulam , Liñán Francisco
Published: October 2013

Purpose

– The purpose of this paper is to examine under-researched psychological and environmental factors related to entrepreneurial motivation and intention. This helps us to explore the links between risk perception (risk as opportunity and risk as threat), economic context (in a recession), entrepreneurial motivation (personal attitudes and perceived behavioral control) and intention for new venture creation.

Design/methodology/approach

– A sample of 619 individuals from two European countries, Spain and Great Britain, is studied. A range of control variables have been considered, including demographics, human/social capital and country effects. Structural equation modeling is used to analyze the relationships among the model constructs.

Findings

– The structural model broadly holds and adequately fits the data. Entrepreneurial risk perception is strongly linked with entrepreneurial motivation. Entrepreneurial motivation, in turn, is strongly linked with entrepreneurial intention. It suggests, therefore, an indirect effect of risk perception on intentions. Economic context is also linked with risk perception and entrepreneurial intentions.

Research limitations/implications

– Results from this exploratory study suggest a role of risk perception in establishing the entrepreneurial intention of individuals. Therefore, greater attention should be paid to this element in entrepreneurship education programs. Similarly, perceptions about the economic (recessionary) environment and its relationship with risk perception also have to be taken into account, with the purpose of letting students understand the possibilities that are present in a recessionary situation.

Originality/value

– This is the first time that perceptions about risk and the economic context are tested within the theory of planned behavior.
An introduction to structural equation modelling for emergency services and disaster research
Authors: Cruddas Sarah
Published: October 2013

Purpose

– Structural equation modelling (SEM) is becoming a popular technique for analysis and is increasingly being used within emergency services and disaster research. The purpose of this paper is to provide a brief overview of SEM to familiarise emergency service and disaster researchers with the technique.

Design/methodology/approach

– Following a general overview of SEM, including its advantages in relation to other techniques and details of how it should be conducted, current issues surrounding model fit will be discussed.

Findings

– SEM is a highly flexible tool, which has many advantages over other techniques. It has become a much more accessible method of analysis in recent years due to software advancements, providing the potential to produce high-quality research when applied correctly.

Originality/value

– To date SEM has already revealed findings of importance within this field, however, the production of valid and reliable research is dependent upon its correct application. It is hoped that this overview will encourage the use of SEM within emergency service and disaster research in order to provide new insights and enhance public safety and resilience.
Anxiety, stress, and perceived workload during the command and control of computer-simulated fire service training environments
Authors: Michael Young Paul , St Clair Gibson Alan , Partington Elizabeth , Partington Sarah , Wetherell Mark
Published: October 2013

Purpose

– Incidents requiring command and control require all personnel from firefighters (FFs) to the incident commander (IC) to make continuous decisions often with limited information and under acute time-pressure. Therefore, the purpose of this paper is to explore the stress reactivity of specific roles during the command and control of an immersive, computer-based incident.

Design/methodology/approach

– Experienced firefighting personnel undergoing incident command training participated in this study. Participants completed measures of state anxiety and stress immediately before and after taking part in a computer-based simulation of a large-scale incident run in real time. During the simulation personnel assumed one of four roles: IC, sector commander, entry control officer (ECO), and command support officer. Following the simulation personnel then completed measures of perceived workload.

Findings

– No significant changes in state anxiety were observed, but levels of stress and perceived workload were related to task roles. Specifically, ICs reported the greatest levels of mental and temporal demands and stress when compared with ECOs.

Research limitations/implications

– Limitations include the lack of environmental factors (such as rain, darkness, and noise), a relatively small sample size, and the use of self-reported questionnaires.

Practical implications

– The application of immersive training environments as a method of developing FFs experience of incident command roles and skills pertinent to high-acuity, low-frequency events.

Originality/value

– The paper represents one of the first attempts to identify the self-reported anxiety, stress, and perceived workload of specific role demands during the command and control of simulated incidents.