bluuebunny/crossref_metadata_2025 huggingface dataset:
Deformation of White Blood Cells Firmly Adhered to Endothelium
Authors: Szatmary Alex C. , Banton Rohan J. , Eggleton Charles D.
Published: July 2013

Circulating white blood cells adhere to endothelium near an infection site; this occurs because infection causes ligands to be expressed on activated endothelium. Initially, a white blood cell rolls on the substrate, but eventually forms a firm adhesion, allowing it to crawl through the endothelial layer toward the infected tissue. A computational model of bond kinetics, cell deformability, and fluid dynamics was used to model the forces experienced by a cell during this process. The cell was modeled as a fluid-filled membrane; on its surface were hundreds of deformable microvilli—little fingers, ruffles in the white blood cell’s wrinkly membrane. These microvilli were deformable and their tips were decorated with PSGL-1 chemical receptors which bound to P-selectin ligands on the surface. Softer cells and cells subjected to higher fluid shear stress deformed more, and having more contact area, they formed more bonds and were able to resist more hydrodynamic load.
Investigation of the Role of Stress Fiber Contractility and Nucleus Geometry in the Response of Cells to Micropipette Aspiration
Authors: Reynolds Noel H. , Ronan William , Dowling Enda P. , McGarry J. Patrick
Published: July 2013

Remodeling of the actin cytoskeleton plays a critical role in the response of cells to mechanical stimuli. Previous studies have investigated the response of cells to micropipette aspiration using passive visco-elastic models for the cell cytoplasm [1–3].
Reducing Upstream Compliance Induces Downstream High Pulsatility Flow-Dependent Inflammatory Response in Pulmonary Endothelial Cells via TLR2/NF-KB Pathway
Authors: Tan Yan , Tan Wei
Published: July 2013

Pulmonary arterial hypertension (PAH) is a group of chronic, progressive and fatal diseases, characterized by the dysfunction of the small arteries and microvasculature in the pulmonary circulation. Due to high blood pressure and high resistance in the pulmonary arteries, PAH causes detrimental damage on the lung and right heart ventricle. If left untreated, PAH quickly becomes life threatening. Although the exact pathophysiology remains unknown, there is increasing evidence suggesting that inflammation likely plays an important role in inducing and perpetuating the PAH progress. Although anti-inflammatory therapy has been shown effective in certain connective-tissue-disease-associated PAH, this approach has not been tested in other PAH conditions. The potential benefit of anti-inflammatory therapy to treat various PAH conditions could be of importance and require further study on the possible pathological mechanisms underlying the therapeutic effects.
Active Cushion Patterns and Alternating Inflation/Deflation Cycle Times Can Influence Seating Interface Pressures
Authors: Mandala Mahender A. , Lassman Kenneth , Fischer Kenneth J.
Published: July 2013

Intermittent pressure relief has been recommended as a means to lower the risk of pressure ulcer (PU) development [1]. Continuous pressure over skin surface is one of the most significant factors, and in most cases the only requisite factor, that may result PUs. Thus, using an active seat cushion (i.e., a cushion that cyclically changes the area of exposure to pressure) seems like a logical strategy to lower the risk of PU formation in the chair-bound population.
Design and Marker-Based Validation of a Biplane Fluoroscopy System for Studying the Foot and Ankle
Authors: Iaquinto Joseph M. , Tsai Richard , Fassbind Michael J. , Haynor David R. , Sangeorzan Bruce J. , Ledoux William R.
Published: July 2013

The ability to accurately measure three dimensional (3D) bone kinematics is key to understanding the motion of the joints of the body, and how such motion is altered by injury, disease, and treatment. Precise measurement of such kinematics is technically challenging. Biplane fluoroscopy is ideally suited to measure bone motion. Such systems have been developed in the past for both radiographic stereo-photogrammetric analysis (RSA) [1] and the more challenging model-based analysis [2]. Research groups have studied the knee [3,4], shoulder [5] and ankle [6] motion with similar techniques. The work presented here is an initial evaluation of the performance of our system, i.e., a validation that this in-house system can detect magnitudes of motion on-par with other existing systems.
Heterogeneity of Bone Mineral Density and Fatigue Failure of Human Vertebrae
Authors: Yeni Yener N. , Poisson Laila M. , Flynn Michael J.
Published: July 2013

Bone qualities that are measurable via clinically available modalities and that can explain fracture risk beyond what is explainable by bone mineral density (BMD) are of significant interest. Evidence from literature suggests that the heterogeneity of BMD within a vertebra, in addition to the average BMD, may be an important determinant of the mechanical properties of a vertebra 1–3 and risk of a clinical vertebral fracture 4. Much of the experimental evidence comes from tests, in which vertebrae are monotonically loaded and relates BMD heterogeneity to the quasi-static properties of a vertebra 1, 3. The appearance of clinical vertebral fractures is in the form of progressive deformities indicating that fatigue processes are involved. However, the relationships between BMD heterogeneity and fatigue properties of a vertebra are not well-understood.
Lineage Tracing Reveals a New Model for Tendon Growth and Elongation During Development
Authors: Huang Alice H. , Watson Spencer S. , Schweitzer Ronen
Published: July 2013

Tendons are dense, fibrous tissues connecting muscle to bone, and their primary function is to transmit muscle forces to the appropriate skeletal elements, thereby enabling movement. In the limb, flexion and extension of the hand (autopod) and wrist are controlled by long tendons that insert into muscles in the arm (zeugopod) [1]. Although tendons are critically important in mediating joint movement, the cellular and molecular events underlying tendon formation remain largely unknown. Using the transcription factor Scleraxis (Scx), which labels all tendon progenitors, we previously showed that in the mouse limb bud, Scx-expressing tendon progenitors are first induced in the mesenchyme underneath the ectoderm at E10.5; at E12.5, progenitors are loosely organized between the cartilage condensations and developing muscles, condensing to form distinct tendons by E13.5 [2]. By E14.5, limb tendon patterning is largely complete, with continued elongation and deposition of matrix from this stage onward.
Cell Shape Control and Related Focal Adheshion Dynamics on Aligned Fiber Networks
Authors: Sheets Kevin , Nain Amrinder
Published: July 2013

Cellular elasticity, a measure of a cell’s resistance to changing its shape in response to external stimuli, has been shown in the recent past to be a potential indicator of cell health [1]. A variety of methods including AFM techniques [1, 2], magnetic/optical tweezers [3, 4], and micropillar arrays [6–8] have been used to quantify cellular elasticity to identify cell disease state, including stages of progression in cancerous cells. Since cellular behavior is heavily dependent on the physical nature of the surrounding extracellular matrix (ECM), understanding mechanical cell-substrate interactions may lead to connections between the elasticity of a cell and the cell’s health state [1]. In this study, the STEP (Spinneret-based Tunable Engineered Parameters) technique is used to create suspended nanofibrous polystyrene substrates with tight control on fiber diameter and spacing in single and multiple layers. As cells interact with these various substrates, they take on repeatable configurations and allow the probing of biophysical traits. Specifically, cytoskeletal arrangements provide information on the behavior of the cell nucleus, f-actin stress fibers, and focal adhesions via paxillin staining, which allow for calculation of cellular elasticity.
Confidence Intervals for Estimation of the Concentration and Brightness of Multiple Diffusing Species
Authors: Rong Xi , Pryse Kenneth M. , Whisler Jordan A. , Jiang Yanfei , McConnaughey William B. , Melnykov Artem , Genin Guy M. , Elson Elliot L.
Published: July 2013

Lipid nanodomains in cell membranes are believed to play a significant role in replication of enveloped viruses such as bird flu and HIV and signaling mechanisms underlying pathological conditions such as cancer. However, the forces that govern the formation and availability of these “membrane rafts” are uncertain, and even their existence is questioned. The central challenge is that no suitable imaging modalities exist (Elson, et al., 2010). We are developing tools to characterize and visualize dynamics of lipid nanodomains on idealized systems called giant unilamellar vesicles (GUVs) using fluorescence correlation spectroscopy (FCS) (Figure 1).
Bone Response to Exercise During Recovery Between Unloading Bouts in Adult Male Rats
Authors: Shirazi-Fard Y. , Gonzalez E. , Morgan D. S. , Davis J. M. , Shimkus K. L. , Boudreaux R. D. , Bloomfield S. A. , Hogan H. A.
Published: July 2013

Mechanical unloading has deleterious effects on the musculoskeletal system, and exercise offers a way to reduce or reverse these effects. Studies of crew members from the International Space Station have documented bone losses that do not fully recover even years after returning to Earth [1,2], and this raises concerns with repeated missions. We have used the adult hindlimb unloaded (HU) rat model [3] to simulate repeated exposure to microgravity, and to study densitometric and mechanical properties at multiple bone sites. This study focuses on mixed bone sites including proximal tibia metaphysis (PTM), and femoral neck (FN) region which also has a significant clinical relevance. Surprisingly, losses for the 2nd HU were milder than those for the 1st HU for bone mineral content (BMC) and volumetric bone mineral density (vBMD), suggesting a possible protective effect of the 1st HU [4]. Comparison to a separate group exposed to a single period of HU initiated at the same age as the 2nd HU group ruled out age effects contributing to the smaller deficit. BMC and vBMD values returned to baseline but remained below aging cage control (CC) values, raising the question of whether the milder losses for the 2nd HU might be attributable, wholly or partially, to lower levels at the start of the 2nd HU. The goal of the current study was to determine if adding a resistance exercise regimen during recovery from the 1st HU would restore bone properties to CC levels and/or significantly affect the response to the 2nd HU.
The Influence of Polymeric Fiber Stiffness and Alignment on Cytoplasmic Bleb Dynamics and Migration of Glioblastoma Multiforme Cells
Authors: Sharma Puja , Sheets Kevin , Nain Amrinder S.
Published: July 2013

Cell migration is a tightly regulated phenomenon necessary for regular physiologic processes such as wound healing, immune response, embryonic development, growth, and regeneration [1–3]. Consequences of abnormal migratory behaviors include autoimmune diseases and metastasis during cancer progression [4, 5]. Described as one of the hallmarks of cancer, metastasis is a complex multistep process, and is responsible for 90% of cancer deaths in humans. A better understanding of the process of metastasis is of paramount importance in developing efficient cancer treatment therapies and drugs [6].
Comparison of Clinical and Simulation Results for the Stanford Y-Graft Fontan Pilot Trial
Authors: Yang Weiguang , Feinstein Jeffrey A. , Reddy V. Mohan , Chan Frandics P. , Marsden Alison L.
Published: July 2013

Without surgical palliation, single ventricle heart defects are uniformly fatal. A three-staged surgical repair is typically performed on these patients, who are otherwise severely cyanotic. In the third stage, the Fontan procedure, the inferior vena cava (IVC) is connected to the pulmonary arteries (PAs) via a lateral tunnel or extracardiac conduit. Following Fontan completion, deoxygenated blood from the upper and lower body is redirected to the PAs, bypassing the heart.
Interactions of Poloxamer Hydrogel Composites Containing Carbon Nanobrushes With Clinically Relevant Cell Lines
Authors: Marks William H. , Yang Sze C. , Dombi George W. , Bhatia Sujata K.
Published: July 2013

The objective of this work is to study the interactions of an electrically conductive hydrogel composite with different clinically relevant cell lines. The composite is comprised of carbon nanobrushes embedded in a biocompatible poloxamer gel. This work assesses the ability of such composite gels to support the growth of fibroblasts and myoctes and eventually serve as a matrix to stimulate wound closure. In such a model, fibroblasts and myocytes are seeded separately on the composite hydrogel and bathed in culture medium. The experimental model assesses the ability of fibroblasts and myocytes to grow into and adhere to the gel containing carbon nanobrushes. The work demonstrates that carbon nanobrushes can be dispersed within poloxamer gels, and that fibroblasts and myoctyes can proliferate within a poloxamer gel containing homogenously dispersed carbon nanobrushes. Future work will additionally examine the effects of design parameters such as carbon nanobrush content and matrix structure on wound healing, as well as the growth of tendons and other cell lines within the hydrogel composites. This work has relevance for tissue engineering and tissue regeneration in clinical medicine.
Effects of Tissue Dehydration on Optical Diffuse Reflectance and Transmittance in Ex Vivo Porcine Skin
Authors: Vogt William C. , Rylander Christopher G.
Published: July 2013

Soft tissues are heterogeneous materials that may be considered mixtures of water, proteins, and cells. The high degree of mismatch in refractive index between these constituents causes tissues to be highly turbid media [1]. Mechanical optical clearing is a technique for reducing tissue scattering and improving light-based diagnostics and therapeutics. Mechanical optical clearing is performed using indentation to locally modify tissue optical response, and this effect has been shown to be reversible in vivo [2]. This effect is attributed to transient changes in tissue water distribution as a result of interstitial pore flow of water due to tissue compression. This leads to the hypothesis that tissue optical response is also correlated to the tissue’s state of hydration. The goal of this study was to investigate whether or not a difference in tissue water content produces a measurable difference in tissue optical response and to correlate that response with mechanical deformation. Both diffuse reflectance and transmittance were selected as extrinsic optical signals of interest.
CFD Challenge: Solutions Using the Commercial Finite Volume Solver Fluent on Tetrahedral and Polyhedral Meshes
Authors: Malek Adel M. , Lauric Alexandra
Published: July 2013

Research by the Malek Computational Hemodynamics Laboratory has focused on using computational fluid dynamic (CFD) tools to gain an improved insight of the mechanical environment faced by endothelial cells in and around cerebrovascular atherosclerotic and aneurysmal lesions. More recently, we have been interested in studying the effect of endovascular therapies such as aneurysm-occluding coils and intravascular stents on local microhemodynamics.
Temporal Cell Morphology Responses to Mechanical Stimulation
Authors: Wen Shin-Min , Chao Pen-Hsiu Grace
Published: July 2013

Many cells respond to mechanical stimulation by changing their morphology, such as elongation and alignment [1–2]. Studies investigating cell responses to mechanical stimulation are often conducted immediately after unloading [1]. Most tissue engineering studies, however, apply mechanical stimulation with intermittent resting periods and monitor the long term cell reactions. In the current study, we examine the cell morphology change in response to mechanical loading with a 24 hour recovery time. Human mesenchymal stem cells (MSCs) were subjected to dynamic tensile or compressive loadings and their morphological changes were compared to those under static loads. A delayed response was found, in addition to changes in active RhoA signals.
Interfacial Phases on Giant Unilamellar Vesicles
Authors: Jiang Yanfei , Genin Guy M. , Singamaneni Srikanth , Elson Elliot L.
Published: July 2013

Lipid nanodomains in cell membranes are believed to play a significant role in a number of critical cellular processes (Elson, et al., 2010). These include, for example, replication processes in enveloped viruses such as bird flu and HIV and signaling mechanisms underlying pathological conditions such as cancer. Due to the potential for developing new disease treatments through the control of these membrane rafts, the biophysics underlying their formation has been the subject of intense study, much of this focused on domain formation in giant unilamellar lipid vesicles (GUVs), a simplified model system.
Engineered Fibrillar Extracellular Matrices for the Study of Directed Cell Migration
Authors: Baker Brendon M. , Choi Colin K. , Trappmann Britta , Chen Christopher S.
Published: July 2013

The biology of cell adhesion and migration has traditionally been studied on 2D glass or plastic surfaces. While such studies have shed light on the molecular mechanisms governing these processes [1], current knowledge is limited by the dissimilarity between the flat surfaces conventionally employed and the topographically complex extracellular matrix (ECM) cells routinely navigate within the body. On ECM-coated flat surfaces, cells are presented with an unlimited expanse of adhesive ligand and can spread and migrate freely. Conversely, the availability of ligand in vivo is generally restricted to ECM structures, forcing cells to form adhesions in prescribed locations distributed through 3D space depending on the geometry and organization of the surrounding matrix [2]. These physical constraints on cell adhesion likely have profound consequences on intracellular signaling and resulting migration, and calls into question whether the mechanisms and modes of cell motility observed on flat substrates are truly reflective of the in vivo scenario [3]. The topographies of ECMs found in vivo are varied but largely fibrillar, ranging from the tightly crosslinked fibers that form the sheet-like basement membrane, to the structure of fibrin-rich clots and collagenous connective tissues. Collagen comprises approximately 25% of the human body by mass, and as such, purified collagen has served as a popular setting for the study of cell migration within a fibrillar context for many decades [4]. However, a major limitation to the use of these gels is the inability to orthogonally dictate key structural features that impact cell behavior. For example, in contrast to the large range of fiber diameters found in vivo within connective tissue resulting from hierarchical collagen assembly and multiple types of collagens [3], collagen gels are limited to fibril diameters of ∼500nm. Furthermore, recreating the structural anisotropy common to connective tissues in collagen gels is technically challenging [5]. Thus, there remains a significant need for engineered fibrillar materials that afford precise and independent control of architectural and mechanical features for application in cell biology. In this work, we develop two approaches to fabricating fibrillar ECMs in order to study cell adhesion and migration in vitro.
Biomechanics of the Cervical Spine Under Compressive Loading in Flexion and Extension: Muscles Net Moment Determination
Authors: Mesfar Wissal , Moglo Kodjo
Published: July 2013

Muscles in the cervical spine are responsible for guiding the head and for conserving its posture. The weight of the head (∼40N) exerts a continuous compressive load that should be monitored by the neck muscles. Wearing a helmet in many sports or military and work activities increases the compressive loading on the head as well as the involvement of the muscles to counterbalance the impact of this supplemental weight. The compressive load is estimated to range from 120 to 1200N [1]. This loading influences all the biomechanics of the head and neck complex and its musculature. Experimental and numerical studies were involved to determine the biomechanical response of the head and neck [2]. In this study and based on our finite element model, we aim to estimate the biomechanical impact of a compressive load varying from 0N to 100N on the head and neck complex at four positions, neutral position, 10 and 20 deg of head flexion and 10 deg of head extension. An evaluation of the required muscles net moment to conserve the head at each posture will also be done.
Feshbach resonance: A one dimensional example
Authors: Taron Josep
Published: July 2013

We present a simple, one-dimensional example of a total spin-1/2 atom that interacts with another static atom in the presence of an external magnetic field. The interaction consists of delta potentials that act differently with each of the two components of the wavefunction. The system has two coupled channels, admits a closed solution, and features the Feshbach resonance phenomenon by proper tuning of the magnetic field.
Kinetic exchange models: From molecular physics to social science
Authors: Patriarca Marco , Chakraborti Anirban
Published: July 2013

We discuss several multi-agent models that have their origin in the kinetic exchange theory of statistical mechanics and have been recently applied to a variety of problems in the social sciences. This class of models can be easily adapted for simulations in areas other than physics, such as the modeling of income and wealth distributions in economics and opinion dynamics in sociology.
Comparison of electromagnetic and gravitational radiation: What we can learn about each from the other
Authors: Price Richard H. , Belcher John W. , Nichols David A.
Published: July 2013

We compare the nature of electromagnetic fields and gravitational fields in linearized general relativity. We carry out this comparison both mathematically and visually. In particular, the “lines of force” visualizations of electromagnetism are contrasted with the recently introduced tendex/vortex eigenline technique for visualizing gravitational fields. Specific solutions, visualizations, and comparisons are given for an oscillating point quadrupole source. Among the similarities illustrated are the quasistatic nature of the near fields, the transverse 1/r nature of the far fields, and the interesting intermediate field structures connecting these two limiting forms. Among the differences illustrated are the meaning of field line motion and of the flow of energy.
Landing spacecraft on Mars and other planets: An opportunity to apply introductory physics
Authors: Withers Paul
Published: July 2013

The Curiosity rover safely landed on Mars after “seven minutes of terror” passing through the Martian atmosphere. In order to land safely, Curiosity had to decelerate from speeds of several kilometers per second and reach zero speed exactly upon touching down on the surface. This was accomplished by a combination of atmospheric drag on the enclosed spacecraft during the initial hypersonic entry, deployment of a large parachute, and retrorockets. Here, we use the familiar concepts of introductory physics to explain why all three of these factors were necessary to ensure a safe landing. In particular, we analyze the initial deceleration of a spacecraft at high altitudes, its impact speed if a parachute is not used, its impact speed if a parachute is used, and the duration of its descent on a parachute, using examples from Curiosity and other missions.
Thermodynamic model for bouncing charged particles inside a capacitor
Authors: Rezaeizadeh Amin , Mameghani Pooya
Published: July 2013

We introduce an equation of state for a conducting particle inside a charged parallel-plate capacitor and show that it is similar to the equation of state for an ideal gas undergoing an adiabatic process. We describe a simple experiment that shows reasonable agreement with the theoretical model.
Mansuripur's paradox
Authors: Griffiths David J. , Hnizdo V.
Published: July 2013

A recent article by Mansuripur claims that the Lorentz force law is incompatible with special relativity. We discuss the “paradox” on which this claim is based. The resolution depends on whether one assumes a “Gilbert” model for the magnetic dipole (separated monopoles) or the standard “Ampère” model (a current loop). The former case was treated in these pages many years ago; the latter, as several authors have noted, constitutes an interesting manifestation of “hidden momentum.”
H7N9 Influenza Viruses Are Transmissible in Ferrets by Respiratory Droplet
Authors: Zhang Qianyi , Shi Jianzhong , Deng Guohua , Guo Jing , Zeng Xianying , He Xijun , Kong Huihui , Gu Chunyang , Li Xuyong , Liu Jinxiong , Wang Guojun , Chen Yan , Liu Liling , Liang Libin , Li Yuanyuan , Fan Jun , Wang Jinliang , Li Wenhui , Guan Lizheng , Li Qimeng , Yang Huanliang , Chen Pucheng , Jiang Li , Guan Yuntao , Xin Xiaoguang , Jiang Yongping , Tian Guobin , Wang Xiurong , Qiao Chuanling , Li Chengjun , Bu Zhigao , Chen Hualan
Published: July 2013

H7N9 Adaptation

Puzzling and alarming reports of an outbreak in early 2013 of human infections by a low-pathogenicity avian influenza virus has rocked the poultry industry in central eastern China and brought fears of initiating a human pandemic. Over 130 human cases have been reported with 37 deaths until closure of poultry markets accompanied a near-cessation of human case reports. From surveillance sampling of >10,000 isolates obtained during April 2013,

Zhang
et al.

(p.
410
, published online 18 July) took 37 isolates of avian origin H7N9 and compared them to human H7N9 isolates. The majority of H7N9 isolates came from live poultry markets, although some originated in pigeons. Sequence analysis indicated that the chicken isolates had retained the avian characteristics at sites on the influenza genes for PB2 and the surface hemagglutinin HA, where adaptive mutations have been observed before. Sequence analysis also showed a higher variability in the internal genes than in HA and neuraminidase NA. By using glycan arrays, it was shown that avian and human isolates bound to human, but also to some extent to avian, receptors. As expected, the virus replicated well in chickens without causing disease, whereas in mice only the human isolates were highly pathogenic. The human virus, but not the avian, transmitted between ferrets through the air.
Positive Feedback Between PU.1 and the Cell Cycle Controls Myeloid Differentiation
Authors: Kueh Hao Yuan , Champhekar Ameya , Nutt Stephen L. , Elowitz Michael B. , Rothenberg Ellen V.
Published: July 2013

A Different Cycle for Differentiation

The regulated expression of transcription factors determines cell fate decisions during cell differentiation. The transcription factor PU.1 is an important determinant in the differentiation of hematopoietic progenitors to lymphocytes or myeloid cells, where high expression induces macrophage differentiation, whereas low expression leads to the development of B lymphocytes. How PU.1 expression levels are regulated during this cell fate choice, however, is not well understood.

Kueh
et al.

(p.
670
, published online 18 July) found that in mice, reduced transcription of PU.1 led to its reduced expression in developing B lymphocytes, whereas in macrophages, PU.1 was able to accumulate stably because of a lengthening of the cell cycle. Exogenous expression of PU.1 in progenitors supported cell cycle lengthening and macrophage differentiation, and mathematical modeling suggested that such a feedback loop could maintain a slow-dividing macrophage developmental state.
Complete Nucleotide Sequence of Porcine Circovirus 2 Isolated from Piglets in China
Authors: Hu Xiaoliang , Tian Zhige , Peng Bo , Chen Hui , Qu Juanjuan
Published: July 2013

A new strain of canine distemper virus, strain HX, has been isolated from piglets in China, and its complete genome has been sequenced and analyzed. Phylogenetic analysis suggests that HX belongs to the 2d genotype cluster and it is highly prevalent in China.
Full Genome Sequence of a Natural Reassortant H9N2 Avian Influenza Virus Isolated from Domestic Ducks in Jiangsu Province, China
Authors: Zhao Mingjun , Liu Qingtao , Sun Qing , Zhang Wenjun , Zhao Guo , Gu Min , Wang Xiaoquan , Hu Shunlin , Liu Xiaowen , Liu Xiufan
Published: July 2013

In this study, the complete genomic sequence of a novel reassortant H9N2 avian influenza virus (AIV) from domestic ducks in eastern China was reported. Phylogenetic analysis showed that seven of the eight genes were all highly homologous to the chicken-origin H9N2 viruses, whereas the PB2 gene was homologous to the human-origin H1N1 virus, which suggested that domestic ducks might play a key role in the genetic reassortment and evolution of H9N2 AIVs in eastern China.
Complete Genome Sequence of Avian Influenza Virus A/chicken/Jiangsu/1001/2013(H5N2), Demonstrating Continuous Reassortance of H5N2 in China
Authors: Mi Zhiqiang , Liu Wei , Fan Hang , An Xiaoping , Pei Guangqian , Wang Wei , Xu Xiaomeng , Ma Maijuan , Zhang Zhiyi , Cao Wuchun , Tong Yigang
Published: July 2013

Avian influenza virus A/chicken/Jiangsu/1001/2013(H5N2) was identified from a healthy chicken in an eastern China poultry market. Whole-genome analysis demonstrated that the H5N2 virus originated from a reassortance between a previous A/chicken/Hebei/1102/2010(H5N2) virus and an endemic H5N1 virus. The results indicated that continuing reassortance of H5N2 has been occurring in domestic poultry of China.
Draft Genome Sequence of the Hydrogen- and Ethanol-Producing Anaerobic Alkalithermophilic Bacterium
Caloramator celer
Authors: Ciranna Alessandro , Larjo Antti , Kivistö Anniina , Santala Ville , Roos Christophe , Karp Matti
Published: July 2013

Caloramator celer
strain JW/YL-NZ35 is a Gram-positive thermophilic, alkalitolerant, and strictly anaerobic bacterium capable of producing hydrogen and ethanol under extreme conditions. The draft genome sequence presented here will provide valuable information to further explore the physiology of this species and its potential for biofuel production.
Genome Sequence of Streptomyces violaceusniger Strain SPC6, a Halotolerant Streptomycete That Exhibits Rapid Growth and Development
Authors: Chen Ximing , Zhang Binglin , Zhang Wei , Wu Xiukun , Zhang Manxiao , Chen Tuo , Liu Guangxiu , Dyson Paul
Published: July 2013

Streptomyces violaceus
niger

strain SPC6 is a halotolerant streptomycete isolated from the Linze desert in China. The strain has a very high growth rate and a short life cycle for a streptomycete. For surface-grown cultures, the period from spore germination to formation of colonies with mature spore chains is only 2 days at 37°C. Additionally, the strain is remarkably resistant to osmotic, heat, and UV stress compared with other streptomycetes. Analysis of the draft genome sequence indicates that the strain has the smallest reported genome (6.4 Mb) of any streptomycete. The availability of this genome sequence allows us to investigate the genetic basis of adaptation for growth in an extremely arid environment.
Complete Genome Sequence of a Pseudomonas putida Clinical Isolate, Strain H8234
Authors: Molina Lázaro , Bernal Patricia , Udaondo Zulema , Segura Ana , Ramos Juan-Luis
Published: July 2013

We report the complete genome sequence of
Pseudomonas putida
strain H8234, which was isolated from a hospital patient presenting with bacteremia. This strain has a single chromosome (6,870,827 bp) that contains 6,305 open reading frames. The strain is not a pathogen but exhibits multidrug resistance associated with 40 genomic islands.
Draft Genome Sequence of the Moderately Halophilic Gammaproteobacterium Halomonas anticariensis FP35
T
Authors: Tahrioui Ali , Quesada Emilia , Llamas Inmaculada
Published: July 2013

Halomonas anticariensis
strain FP35
T
is a moderately halophilic bacterium isolated from a soil sample taken from Fuente de Piedra, a saline wetland in the province of Málaga (Spain), which produces an exopolysaccharide and quorum-sensing signaling molecules of the type
N
-acylhomoserine lactone. We report here the draft genome sequence of this gammaproteobacterium.
Draft Genome Sequences of Two Yersinia pseudotuberculosis ST43 (O:1b) Strains, B-7194 and B-7195
Authors: Blouin Yann , Platonov Mikhail E. , Pourcel Christine , Evseeva Vera V. , Afanas'ev Maxim V. , Balakhonov Sergey V. , Anisimov Andrey P. , Vergnaud Gilles
Published: July 2013

We report the first draft genome sequences of two
Yersinia pseudotuberculosis
sequence type 43 (ST43) (O:1b) strains, B-7194 and B-7195, isolated in Russia. The total lengths of the assemblies are 4,427,121 bp and 4,608,472 bp, and 3,819 and 4,018 coding sequences, respectively, were predicted within the genomes.
Draft Genome Sequence of Enterococcus faecium Strain CRL 1879, Isolated from a Northwestern Argentinian Artisanal Cheese
Authors: Suárez Nadia E. , Saavedra Lucila , Složilová Ivana , Bonacina Julieta , Demnerová Kateřina , Sesma Fernando
Published: July 2013

We report the draft genome sequence of the bacteriocin producer
Enterococcus faecium
strain CRL 1879, isolated from a northwestern Argentinian artisanal cheese. The draft genome sequence is composed of 73 contigs for 2,886,747 bp, with 3,140 protein-coding genes. Six biosynthetic clusters for bacteriocin class II production were found. Typical virulence determinants, which have relevance in food safety, were not present.
Estimates of restrictive ventilatory defect in the mining industry. Considerations for epidemiological investigations: a cross-sectional study
Authors: Odo Nnaemeka U , Mandel Jeffrey H , Perlman David M , Alexander Bruce H , Scanlon Paul D
Published: July 2013

Objectives

(1) To assess the impact of American Thoracic Society and European Respiratory Society (ATS/ERS) ‘acceptability’ and ‘usability’ criteria for spirometry on the estimates of restrictive ventilatory defect in a population of taconite miners. (2) To compare estimates of restrictive ventilatory defect with three different pulmonary function tests (spirometry, alveolar volume (VA) and diffusing capacity (DL,CO)). (3) To assess the role of population characteristics on these estimates.

Design

Cross-sectional study.

Setting

Current and former workers in six current taconite mining operations of northeastern Minnesota were surveyed.

Participants

We attempted to enrol 3313 participants. Of these, 1353 responded while 1188 current and former workers fully participated in the survey and 1084 performed complete pulmonary function testing and were assessed.

Primary and secondary outcome measures

We applied ATS/ERS acceptability criteria for all tests and categorised participants into groups according to whether they fully met, partially met or did not meet acceptability criteria for spirometry. Obstruction and restriction were defined utilising the lower limit of normal for all tests. When using VA, restriction was identified after excluding obstruction.

Results

Only 519 (47.9%) tests fully met ATS/ERS spirometry acceptability criteria. Within this group, 5% had obstruction and 6%, restriction on spirometry. In contrast, among all participants (N=1084), 16.8% had obstruction, while 4.5% had restriction. VA showed similar results in all groups after obstruction was excluded. Impaired gas transfer (reduced DL,CO) was identified in less than 50% of restriction identified by either spirometry or VA. Body mass index (BMI) was significantly related to spirometric restriction in all groups.

Conclusions

Population estimates of restriction using spirometry or VA varied by spirometric acceptability criteria. Other factors identified as important considerations in the estimation of restrictive ventilatory defect included increased BMI and gas transfer impairment in a relatively smaller proportion of those with spirometric restriction. These insights are important when interpreting population-based physiological data in occupational settings.
Value of a modified early obstetric warning system (MEOWS) in managing maternal complications in the peripartum period: an ethnographic study
Authors: Mackintosh Nicola , Watson Kylie , Rance Susanna , Sandall Jane
Published: July 2013

Objective

To explore implementation of the modified early obstetric warning system (MEOWS) in practice to further understanding about the influence of contextual factors.

Methods

An ethnographic study using observations (>120 h), semi-structured interviews (n=45) and documentary review was performed in the maternity services in two UK hospitals over a 7-month period. Doctors, midwives and managers participated in the study and data were analysed thematically.

Results

For women admitted to hospital in the antenatal and postnatal period with an established risk of morbidity, the MEOWS enabled communication about vital signs from junior to senior midwives and obstetricians. The trigger prompts helped shape shared understandings of maternal complications. However, midwifery and obstetric staff questioned the added value of an extra chart in the postnatal period given the low incidence of maternal complications and the resulting increase in workload. In an effort to prioritise workload demands and respond to the immediate needs of both women and their babies, midwives exercised professional discretion regarding its use. However, discretionary use of MEOWS meant the loss of a potential universal safety net for detection of deterioration.

Conclusions

Despite a decade of use in acute settings, research into the effectiveness of early warning systems still yields conflicting results. Widespread policy support for the MEOWS is based on its intuitive appeal and no validated system for use in the maternity population currently exists. Our findings suggest that, while the MEOWS has value in structuring the surveillance of hospitalised women with an established risk of morbidity, the complexities of managing risk and safety within the maternity pathway, the associated opportunity costs of MEOWS and variation in implementation currently call into question its role for routine use.
Factors at presentation predictive of a requirement for endoscopic therapy in patients presenting with overt upper gastrointestinal haemorrhage: a retrospective observational study
Authors: Irwin James , Ferguson Reid , Weilert Frank , Smith Anthony
Published: July 2013

Introduction

In patients with upper gastrointestinal haemorrhage (UGIH), endoscopic treatment of high-risk lesions reduces mortality. Performing out of office hours endoscopy places a strain on endoscopy services. This analysis aims to identify factors at presentation associated with lesions requiring endoscopic therapy, allowing triage of those likely to receive benefit from acute out of hours endoscopy.

Methods

Patients presenting between 17 March 2001 and 12 October 2010 with UGIH had clinical and laboratory features on presentation, endoscopic findings and administered treatment recorded. Patients with known cirrhotic liver disease were excluded. Logistic regression was performed, identifying factors at presentation associated with a requirement of endoscopic therapy (RET), which were then used to create a scoring system predictive of RET.

Results

In all, 1492 patients were analysed. The presence on presentation of fresh melaena (OR = 3.18, p<0.001), fresh haematemesis (OR=2.13, p<0.001), haemoglobin<130 g/L (OR=2.65, p<0.001), urea >10 mmol/L (OR=2.10, p<0.001), systolic blood pressure <100 mm  Hg (OR=1.85, p<0.001), inpatient status (OR=1.43, p=0.04), a history of peptic ulcer disease (OR=1.96, p=0.02), male sex (OR=1.45, p=0.01), presentation within 8 h of symptom onset (OR=1.48, p=0.02), coffee ground vomitus (OR=0.47, p=0.004) and warfarin use (OR=0.57, p=0.005) were associated with RET. Using a simple scoring system (fresh haematemesis=2, fresh melaena=2, haemoglobin <130=2, urea >10=1, BP <100=1, male sex=1, history of peptic ulcer disease=1), a score ≥7 was associated with RET in 45% of cases and a score ≤4 in 7%.

Conclusions

Application of this scoring system when assessing patients presenting with UGIH out of office hours may help predict the likelihood of RET, and aid in the triage of endoscopy. Prospective validation of this score in an external cohort is required.
Hospitalisation for depressive disorder following unemployment—differentials by gender and immigrant status: a population-based cohort study in Sweden
Authors: Hollander Anna-Clara , Bruce Daniel , Ekberg Jan , Burström Bo , Ekblad Solvig
Published: July 2013

Background

The association between unemployment and poor mental health in general is explained by both causation and selection. The aim was to study whether experiencing unemployment was a risk factor for hospitalisation for depressive disorder specifically, and whether gender and immigrant status modified the hypothesised risk.

Methods

A register-based prospective cohort study, 2000–2006, of persons aged 18–64 with a strong connection to the Swedish labour market.Outcome: hospital admission for a depressive episode; F32 in International Classification of Diseases, 10th revision.Exposure: employment status.Explanatory variables: gender and immigrant status. Confounders: age group, education and marital status. Cox regression models were used to estimate HRs with 95% CIs.

Results

The cohort comprised 3 284 896 adults, 47.5% women. An excess relative risk for hospitalisation was found among those who became unemployed (HR=1.94, 95% CI 1.85 to 2.03). Foreign-born women who experienced unemployment had the highest relative risk (HR=3.47 95% CI 3.02 to 3.98).

Conclusions

Among persons with a strong connection to the labour market experiencing unemployment, is a risk factor for hospitalisation for depressive disorders. Unemployed foreign-born women had the highest relative risk compared with all Swedish born, all foreign-born men and to employed foreign-born women.
Legislative epidemics: the role of model law in the transnational trend to criminalise HIV transmission
Authors: Grace Daniel
Published: July 2013

HIV-related state laws are being created transnationally though the use of omnibus model laws. In 2004, the US Agency for International Development (USAID) funded the creation of one such guidance text known as the USAID/Action for West Africa Region Model Law, or N'Djamena Model Law, which led to the rapid spread of HIV/AIDS laws, including the criminalisation of HIV transmission, across much of West and Central Africa (2005–2010). In this article, I explicate how an epidemic of highly problematic legislation spread across the region as a result of a text-mediated work process enabled through model laws. I theorise the textual genre of model laws arguing that these texts are best understood as ‘preoperative documents’ which, when activated, can lead to swift legislative reform in and beyond the field of HIV/AIDS governance. The legislative process being investigated was made visible through participant observation, archival research, textual analysis and informant interviews with national and international stakeholders (n=32). This involved ethnographic research in Canada, the USA, Switzerland, Austria, South Africa and Senegal (2010–2011). The untold policy processes and narratives explored in this article make evident how the work of contesting problematic HIV/AIDS model laws and newly drafted state laws involves both creating new texts and contesting the legitimacy and efficacy of others.
Aspiration thrombectomy in concert with stent thrombectomy
Authors: Dumont Travis M , Mokin Maxim , Sorkin Grant C , Levy Elad I , Siddiqui Adnan H
Published: July 2013

In the SWIFT and TREVO 2 trials, aspiration thrombectomy was not able to be performed. Outside these studies, in post-market application, the interventionist can use aspiration thrombectomy in addition to stent device thrombectomy. This technique is described in detail in the present report. Combined aspiration/stentriever thrombectomy may improve recanalization efforts, simplify a second thrombectomy attempt if necessary and may limit distal embolization.
Veterinary business management education: why, how, when and who?
Authors: Sykes Ben
Published: July 2013

As with clinical skills, veterinary business skills cannot be acquired overnight and developing them should be part of the process of lifelong learning, says Ben Sykes
A behavioural framework for trapping success and its application to invasive sea lamprey
Authors: Bravener Gale A. , McLaughlin Robert L.
Published: July 2013

Scientific advances are needed to contend with invasive species. Trapping is often used for control or assessment, and understanding the invasive species’ behaviour is important for trapping success. A framework linking behaviour to trapping success and management responses was used to test hypotheses for the low trapping success of invasive sea lamprey (Petromyzon marinus) in the St. Marys River connecting Lakes Superior and Huron. Behaviour of sea lamprey approaching and at traps was quantified using external and internal tags and video. Multistate Markov models identified phenotypic and environmental factors influencing trapping success. Low trapping success for invasive sea lamprey in the St. Marys River is due to individuals not encountering traps, not entering upon encounter, not remaining at the trap, and not returning upon departure. All trapped lamprey were retained. Encounter with, and entrance into, traps varied with sea lamprey class, release date, and time of day, but not body length or river discharge. The conceptual and analytical methods applied here could be used to understand and improve trapping success for other invasive animals.
Passivity analysis and passification for a class of switched stochastic systems with time-varying delay
Authors: Jia Huimei , Xiang Zhengrong
Published: July 2013

This paper is concerned with the problems of passivity analysis and passification for a class of switched stochastic systems with time-varying delay. Firstly, based on the multiple storage functions approach, a delay-dependent sufficient condition for the underlying systems to be stochastically passive is derived in terms of linear matrix inequalities. Then, based on the obtained passivity condition, a state feedback passive controller is designed. Finally, two numerical examples are presented to illustrate the effectiveness of the proposed method.
Nonlinear diffusion in a plane surface
Authors: Janavičius A.J. , Turskienė S.
Published: July 2013

Diffusion is the result of Brownian motion and must occur with a finite velocity. The earlier presented nonlinear diffusion equation, with diffusion coefficients that are directly proportional to the concentration of impurities, defines the maximum depth of penetration. For nonlinear diffusion from a constant source, the depth of the impurities’ penetration is directly proportional to the square root of the diffusion time. Profiles of nonlinear solutions differ from classical linear solutions on great distances and are in good fitting with experiment. We increased the accuracy of the approximate analytical solutions for nonlinear diffusion in the plane from a square infinite source with fixed initial impurity concentrations in the corners. The nonlinear diffusion equation for the solution was transformed by introducing similarity variables.