bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPUTED TOMOGRAPHY AND POSITIVE CONTRAST COMPUTED TOMOGRAPHIC ARTHROGRAPHY OF THE CANINE SHOULDER: NORMAL ANATOMY AND EFFECTS OF LIMB POSITION ON VISIBILITY OF SOFT TISSUE STRUCTURES
Authors: Reis Silva Henrique , Uosyte Raimonda , Clements Dylan Neil , Bergkvist Gurå Therese , Schwarz Tobias
Published: May 2013

Soft tissue injuries of the shoulder are an important cause of forelimb lameness in dogs. The objectives of this canine cadaver study were to describe normal anatomy of shoulder soft tissue structures using computed tomography (CT) and computed tomographic arthrography (CTA) and to determine the effects of positioning on visualization of shoulder soft tissue structures. Thirteen forelimbs were removed from eight canine cadavers. Two forelimbs were used for contrast dose optimization. For the remaining 11 forelimbs, shoulder CT and CTA were performed using three defined joint angles (140°, 90°, and 70°). For three forelimbs, CT and CTA images were compared with frozen anatomic sections to describe normal anatomy. Ten forelimbs were used for analysis of positioning effects. Soft tissue structures evaluated were the joint capsule, cartilage, ligaments, tendons, and muscles. A visual assessment score was assigned to each structure using a consensus of two observers. The range and mode of scores were calculated and compared for each modality and limb position. The shoulder joint capsule and medial and lateral glenohumeral ligaments were completely visible with CTA. All tendons and muscles were visualized in all the examinations except for the teres minor muscle tendon and the coracobrachialis muscle, which were not visible on all scans. Positioning the limb in an extended position significantly improved visualization of most soft tissue shoulder structures. Shoulder cartilage was best seen with CTA and with neutral or flexed positioning of the shoulder. Findings indicated that both CT and CTA are feasible imaging techniques for visualization of soft tissue structures of the canine shoulder.
An Assessment of Global Ocean Thermal Energy Conversion Resources With a High-Resolution Ocean General Circulation Model
Authors: Rajagopalan Krishnakumar , Nihous Gérard C.
Published: May 2013

Global rates of ocean thermal energy conversion (OTEC) are assessed with a high-resolution (1 deg × 1 deg) ocean general circulation model (OGCM). In numerically intensive simulations, the OTEC process is represented by a pair of sinks and a source of specified strengths placed at selected water depths across the oceanic region favorable for OTEC. Results broadly confirm earlier estimates obtained with a coarse (4 deg × 4 deg) OGCM, but with the greater resolution and more elaborate description of key physical oceanic mechanisms in the present case, the massive deployment of OTEC systems appears to affect the global environment to a relatively greater extent. The maximum global OTEC power production drops to 14 TW, or about half of previously estimated levels, but it would be achieved with only one-third as many OTEC systems. Environmental effects at maximum OTEC power production are generally similar in both sets of simulations. The oceanic surface layer would cool down in tropical OTEC regions with a compensating warming trend elsewhere. Some heat would penetrate the ocean interior until the environment reaches a new steady state. A significant boost of the oceanic thermohaline circulation (THC) would occur. Although all simulations with given OTEC flow singularities were run for 1000 years to ensure stabilization of the system, convergence to a new equilibrium was generally achieved much faster, i.e., roughly within a century. With more limited OTEC scenarios, a global OTEC power production of the order of 7 TW could still be achieved without much effect on ocean temperatures.
Parametric Study of a Flat Plate Wick Assisted Heat Pipe Solar Collector
Authors: Taoufik Brahim , Foued Mhiri , Abdelmajid Jemni
Published: May 2013

The use of heat pipes in solar collectors offers several advantages regarding flexibility in operation and application, as they are very efficient in transporting heat even under a small temperature difference. Compared with other systems powered by evacuated tube collectors or flat plate solar collectors using a wickless heat pipe, little attention has been paid to a flat plate solar collectors wick assisted heat pipe. In this paper an analytical model based on energy balance equations assuming a steady state condition was developed to evaluate the thermal efficiency of a flat plate wick assisted heat pipe solar collector. Parameters which affect the collector efficiency are identified, such as tube spacing distance, gap spacing between the absorber plate and the glazing cover, and the emissivity of the absorber plate. The results reflect the contribution and significance of each of these parameters to the collector overall heat loss coefficients. Three heat pipe working fluids are examined and results show that acetone performs better than methanol and ethanol.
A Phase Field Approach for Multicellular Aggregate Fusion in Biofabrication
Authors: Yang Xiaofeng , Sun Yi , Wang Qi
Published: May 2013

We present a modeling and computational approach to study fusion of multicellular aggregates during tissue and organ fabrication, which forms the foundation for the scaffold-less biofabrication of tissues and organs known as bioprinting. It is known as the phase field method, where multicellular aggregates are modeled as mixtures of multiphase complex fluids whose phase mixing or separation is governed by interphase force interactions, mimicking the cell-cell interaction in the multicellular aggregates, and intermediate range interaction mediated by the surrounding hydrogel. The material transport in the mixture is dictated by hydrodynamics as well as forces due to the interphase interactions. In a multicellular aggregate system with fixed number of cells and fixed amount of the hydrogel medium, the effect of cell differentiation, proliferation, and death are neglected in the current model, which can be readily included in the model, and the interaction between different components is dictated by the interaction energy between cell and cell as well as between cell and medium particles, respectively. The modeling approach is applicable to transient simulations of fusion of cellular aggregate systems at the time and length scale appropriate to biofabrication. Numerical experiments are presented to demonstrate fusion and cell sorting during tissue and organ maturation processes in biofabrication.
Complex Matrix Remodeling and Durotaxis Can Emerge From Simple Rules for Cell-Matrix Interaction in Agent-Based Models
Authors: Reinhardt James W. , Krakauer Daniel A. , Gooch Keith J.
Published: May 2013

Using a top-down approach, an agent-based model was developed within NetLogo where cells and extracellular matrix (ECM) fibers were composed of multiple agents to create deformable structures capable of exerting, reacting to, and transmitting mechanical force. At the beginning of the simulation, long fibers were randomly distributed and cross linked. Throughout the simulation, imposed rules allowed cells to exert traction forces by extending pseudopodia, binding to fibers and pulling them towards the cell. Simulated cells remodeled the fibrous matrix to change both the density and alignment of fibers and migrated within the matrix in ways that are consistent with previous experimental work. For example, cells compacted the matrix in their pericellular regions much more than the average compaction experienced for the entire matrix (696% versus 21%). Between pairs of cells, the matrix density increased (by 92%) and the fibers became more aligned (anisotropy index increased from 0.45 to 0.68) in the direction parallel to a line connecting the two cells, consistent with the “lines of tension” observed in experiments by others. Cells migrated towards one another at an average rate of ∼0.5 cell diameters per 10,000 arbitrary units (AU); faster migration occurred in simulations where the fiber density in the intercellular area was greater. To explore the potential contribution of matrix stiffness gradients in the observed migration (i.e., durotaxis), the model was altered to contain a regular lattice of fibers possessing a stiffness gradient and just a single cell. In these simulations cells migrated preferentially in the direction of increasing stiffness at a rate of ∼2 cell diameter per 10,000 AU. This work demonstrates that matrix remodeling and durotaxis, both complex phenomena, might be emergent behaviors based on just a few rules that control how a cell can interact with a fibrous ECM.
Simulation of Aperiodic Bipedal Sprinting
Authors: Celik Huseyin , Piazza Stephen J.
Published: May 2013

Synthesis of legged locomotion through dynamic simulation is useful for exploration of the mechanical and control variables that contribute to efficient gait. Most previous simulations have made use of periodicity constraints, a sensible choice for investigations of steady-state walking or running. Sprinting from rest, however, is aperiodic by nature and this aperiodicity is central to the goal of the movement, as performance is determined in large part by a rapid acceleration phase early in the race. The purpose of this study was to create a novel simulation of aperiodic sprinting using a modified spring-loaded inverted pendulum (SLIP) biped model. The optimal control problem was to find the set of controls that minimized the time for the model to run 20 m, and this problem was solved using a direct multiple shooting algorithm that converts the original continuous time problem into piecewise discrete subproblems. The resulting nonlinear programming problem was solved iteratively using a sequential quadratic programming method. The starting point for the optimizer was an initial guess simulation that was a slow alternating-gait “jogging” simulation developed using proportional-derivative feedback to control trunk attitude, swing leg angle, and leg retraction and extension. The optimized aperiodic sprint simulation solution yielded a substantial improvement in locomotion time over the initial guess (2.79 s versus 6.64 s). Following optimization, the model produced forward impulses at the start of the sprint that were four times greater than those of the initial guess simulation, producing more rapid acceleration. Several gait features demonstrated in the optimized sprint simulation correspond to behaviors of human sprinters: forward trunk lean at the start; straightening of the trunk during acceleration; and a dive at the finish. Optimization resulted in reduced foot contact times (0.065 s versus 0.210 s), but contact times early in the optimized simulation were longer to facilitate acceleration. The present study represents the first simulation of multistep aperiodic sprinting with optimal controls. Although the minimized objective function was simple, the model replicated several complex behaviors such as modulation of the foot contact and executing a forward dive at the finish line. None of these observed behaviors were imposed explicitly by constraints but rather were “discovered” by the optimizer. These methods will be extended by addition of musculotendon actuators and joints in order to gain understanding of the influence of musculoskeletal mechanics on gait speed.
The Importance of Patient-Specific Regionally Varying Wall Thickness in Abdominal Aortic Aneurysm Biomechanics
Authors: Raut Samarth S. , Jana Anirban , De Oliveira Victor , Muluk Satish C. , Finol Ender A.
Published: May 2013

Abdominal aortic aneurysm (AAA) is a vascular condition where the use of a biomechanics-based assessment for patient-specific risk assessment is a promising approach for clinical management of the disease. Among various factors that affect such assessment, AAA wall thickness is expected to be an important factor. However, regionally varying patient-specific wall thickness has not been incorporated as a modeling feature in AAA biomechanics. To the best our knowledge, the present work is the first to incorporate patient-specific variable wall thickness without an underlying empirical assumption on its distribution for AAA wall mechanics estimation. In this work, we present a novel method for incorporating regionally varying wall thickness (the “PSNUT” modeling strategy) in AAA finite element modeling and the application of this method to a diameter-matched cohort of 28 AAA geometries to assess differences in wall mechanics originating from the conventional assumption of a uniform wall thickness. For the latter, we used both a literature-derived population average wall thickness (1.5 mm; the “UT” strategy) as well as the spatial average of our patient-specific variable wall thickness (the “PSUT” strategy). For the three different wall thickness modeling strategies, wall mechanics were assessed by four biomechanical parameters: the spatial maxima of the first principal stress, strain, strain-energy density, and displacement. A statistical analysis was performed to address the hypothesis that the use of any uniform wall thickness model resulted in significantly different biomechanical parameters compared to a patient-specific regionally varying wall thickness model. Statistically significant differences were obtained with the UT modeling strategy compared to the PSNUT strategy for the spatial maxima of the first principal stress (p = 0.002), strain (p = 0.0005), and strain-energy density (p = 7.83 e–5) but not for displacement (p = 0.773). Likewise, significant differences were obtained comparing the PSUT modeling strategy with the PSNUT strategy for the spatial maxima of the first principal stress (p = 9.68 e–7), strain (p = 1.03 e–8), strain-energy density (p = 9.94 e–8), and displacement (p = 0.0059). No significant differences were obtained comparing the UT and PSUT strategies for the spatial maxima of the first principal stress (p = 0.285), strain (p = 0.152), strain-energy density (p = 0.222), and displacement (p = 0.0981). This work strongly recommends the use of patient-specific regionally varying wall thickness derived from the segmentation of abdominal computed tomography (CT) scans if the AAA finite element analysis is focused on estimating peak biomechanical parameters, such as stress, strain, and strain-energy density.
Modeling Stress-Relaxation Behavior of the Periodontal Ligament During the Initial Phase of Orthodontic Treatment
Authors: Romanyk Dan L. , Melenka Garrett W. , Carey Jason P.
Published: May 2013

The periodontal ligament is the tissue that provides early tooth motion as a result of applied forces during orthodontic treatment: a force-displacement behavior characterized by an instantaneous displacement followed by a creep phase and a stress relaxation phase. Stress relaxation behavior is that which provides the long-term loading to and causes remodelling of the alveolar bone, which is responsible for the long-term permanent displacement of the tooth. In this study, the objective was to assess six viscoelastic models to predict stress relaxation behavior of rabbit periodontal ligament (PDL). Using rabbit stress relaxation data found in the literature, it was found that the modified superposition theory (MST) model best predicts the rabbit PDL behavior as compared to nonstrain-dependent and strain-dependent versions of the Burgers four-parameter and the five-parameter viscoelastic models, as well as predictions by Schapery's viscoelastic model. Furthermore, it is established that using a quadratic form for MST strain dependency provides more stable solutions than the cubic form seen in previous studies.
A Preliminary Analysis of the Data From an in Vitro Inflation-Extension Test Can Validate the Assumption of Arterial Tissue Elasticity
Authors: Rachev Alexander , Shazly Tarek
Published: May 2013

The objective of this study is to propose a method for preliminary processing of the experimental data from an inflation-extension test on tubular arterial specimens. The method is based on the condition for existence of a strain energy function (SEF) and can be used to verify whether the data from a certain experiment validate the assumption that the tissue can be considered as an elastic solid. As an illustrative example of the proposed method, experimental data for a porcine renal artery are used and the sources of the error in satisfying the condition of elasticity are analyzed. The results lead to the conclusion that the experimental data for a renal artery validate that the artery exhibits an elastic mechanical response and a constitutive formulation based on the existence of the SEF is justified. A modification of the proposed method for the case of an in-plane biaxial stretching test of mechanically isotropic and orthotropic tissues is considered.
Analytical Solution for Whirling Speeds and Mode Shapes of a Distributed-Mass Shaft With Arbitrary Rigid Disks
Authors: Wu Jong-Shyong , Lin Foung-Tang , Shaw Huei-Jou
Published: May 2013

The purpose of this paper is to present an approach for replacing the effects of each rigid disk mounted on the spin shaft by a lumped mass together with a frequency-dependent equivalent mass moment of inertia so that the whirling motion of a rotating shaft-disk system is similar to the transverse free vibration of a stationary beam and the technique for the free vibration analysis of a stationary beam with multiple concentrated elements can be used to determine the forward and backward whirling speeds, along with mode shapes of a distributed-mass shaft carrying arbitrary rigid disks. Numerical results reveal that the characteristics of whirling motions are significantly dependent on the slopes of the associated natural mode shapes at the positions where the rigid disks are located. Furthermore, the results obtained from the presented analytical method and those obtained from existing literature or the finite element method (FEM) are in good agreement.
Evaluation of Elastic and Plastic Properties of Ni50Al50(at. %) and (Ni40,Pt10)Al50(at. %) Single Crystals Oriented by Means of Scanning Acoustic Microscopy and Depth Sensing Indentation
Authors: Cleymand F. , Villemiane A. , Arab-Tehrany E. , Kahn C. J. F. , Ayadi Z.
Published: May 2013

Scanning acoustic microscopy and depth sensing indentation are two techniques used for extracting Young's, shear, and indentation moduli as well as the hardness of materials. In this work, we have applied these techniques on Ni50Al50(at. %) and (Ni40,Pt10)Al50(at. %) single crystals oriented (1 0 0) and (1 1 1) to measure their Young's modulus by two different techniques of local measurement and also the hardness of these alloys. Quantitative measurements highlight that the addition of 10 at.% of platinum induces a 5% decrease of Young's modulus (from 195 to 184 GPa) homogeneously spread over the surface orientations investigated,an 8% decrease of the indentation modulus, and a 40% increase of hardness without orientation effect.
Compartmentalized Calcium Transients Trigger Dendrite Pruning in
Drosophila
Sensory Neurons
Authors: Kanamori Takahiro , Kanai Makoto I. , Dairyo Yusuke , Yasunaga Kei-ichiro , Morikawa Rei K. , Emoto Kazuo
Published: May 2013

Dendritic Pruning

During metamorphosis,
Drosophila
sensory neurons eliminate their dendritic trees, but axons and soma remain intact.

Kanamori
et al.

(p.
1475
, published online 30 May) demonstrate that compartmentalized calcium transients in dendrites function as the spatiotemporal cue for pruning of unwanted branches. Such a localized calcium signal, induced by a local elevation of branch excitability, activates calcium-dependent proteinases and eventually causes branch death.
The Origin of Lunar Mascon Basins
Authors: Melosh H. J. , Freed Andrew M. , Johnson Brandon C. , Blair David M. , Andrews-Hanna Jeffrey C. , Neumann Gregory A. , Phillips Roger J. , Smith David E. , Solomon Sean C. , Wieczorek Mark A. , Zuber Maria T.
Published: May 2013

Lunar Mascons Explained

The origin of lunar mass concentrations (or mascons), which appear as prominent bull's-eye patterns on gravitational maps of both the near- and far side of the Moon, has been a mystery since they were originally detected in 1968. Using state-of-the-art simulation codes,

Melosh
et al.

(p.
1552
, published online 30 May; see the Perspective by

Montesi

) developed a model to explain the formation of mascons, linking the processes of impact cratering, tectonic deformation, and volcanic extrusion.
Draft Genome Sequence of the Grapevine Dieback Fungus
Eutypa lata
UCR-EL1
Authors: Blanco-Ulate Barbara , Rolshausen Philippe E. , Cantu Dario
Published: May 2013

The vascular pathogen
Eutypa lata
, which causes Eutypa dieback in grapevines, is a major threat to grape production worldwide. Here, we present the first draft genome sequence of
E. lata
(UCR-EL1). The computational prediction and annotation of the protein-coding genes of UCR-EL1 provide an initial inventory of its potential virulence factors.
Complete Genome Sequence of a New H9N2 Avian Influenza Virus Isolated in China
Authors: Wang Jing-Yu , Ren Juan-Juan , Liu Wan-Hua , Tang Pan , Wu Ning , Wang Chi-Young , Chang Ching-Dong , Liu Hung-Jen
Published: May 2013

The complete genomic sequence of a new H9N2 avian influenza virus (AIV), isolated in northwestern China, was determined. Sequence and phylogenetic analyses based on the sequences of eight genomic segments revealed that the isolate is phylogenetically related to the Y280-like sublineage.
Draft Genome Sequences of Two Multidrug-Resistant Acinetobacter baumannii Strains of Sequence Type ST92 and ST96
Authors: Ho Alex Y. M. , Chow Kin-Hung , Law Pierra Y. T. , Tse Herman , Ho Pak-Leung
Published: May 2013

The global epidemiology of multidrug-resistant
Acinetobacter baumannii
is dominated by a limited number of clones. Here, we announce the draft genome sequences of two multidrug-resistant
A. baumannii
strains, 1H8 and 4A3, representing the major epidemic clones, sequence type 92 (ST92) and ST96, respectively.
Complete Genome Sequence of a Novel Human Betapapillomavirus, HPV-159
Authors: Kocjan Boštjan J. , Hošnjak Lea , Seme Katja , Poljak Mario
Published: May 2013

A novel human papillomavirus (HPV), now officially recognized as HPV-159, isolated from an anal swab, was fully cloned, sequenced, and genetically characterized. HPV-159 has a genomic organization that is typical of cutaneotrophic HPV types, and it belongs to the genus
Betapapillomavirus.
Draft Genome Sequence of
Agrobacterium
sp. Strain UHFBA-218, Isolated from Rhizosphere Soil of Crown Gall-Infected Cherry Rootstock Colt
Authors: Dua Ankita , Sangwan Naseer , Kaur Jasvinder , Saxena Anjali , Kohli Puneet , Gupta A. K. , Lal Rup
Published: May 2013

We report here the draft genome sequence of the alphaproteobacterium
Agrobacterium
sp. strain UHFBA-218, which was isolated from rhizosphere soil of crown gall-infected cherry rootstock Colt. The draft genome of strain UHFBA-218 consists of 112 contigs (5,425,303 bp) and 5,063 coding sequences with a G+C content of 59.8%.
Genome Sequence of Clostridium tyrobutyricum ATCC 25755, a Butyric Acid-Overproducing Strain
Authors: Jiang Ling , Zhu Liying , Xu Xian , Li Yanping , Li Shuang , Huang He
Published: May 2013

Clostridium tyrobutyricum
ATCC 25755 is an efficient producer of butyric acid. Here we report a 3.01-Mb assembly of its genome sequence and other useful information, including the coding sequences (CDSs) responsible for an alternative pathway leading to acetate synthesis as well as a series of membrane transport systems.
Genome of the Psychrophilic Bacterium Bacillus psychrosaccharolyticus, a Potential Source of 2′-Deoxyribosyltransferase for Industrial Nucleoside Synthesis
Authors: Fresco-Taboada Alba , del Cerro Carlos , Fernández-Lucas Jesús , Arroyo Miguel , Acebal Carmen , García José L. , de la Mata Isabel
Published: May 2013

Here we report the draft genome sequence of
Bacillus psychrosaccharolyticus
, a cold-adapted bacterium with biotechnological interest. The genome contains genes related to the ability of this microorganism to grow at low temperatures and includes a nucleoside 2′-deoxyribosyltransferase, which can be used in the industrial synthesis of modified nucleosides with therapeutic activity.
Complete Genome Sequence of Mannheimia haemolytica Strain 42548 from a Case of Bovine Respiratory Disease
Authors: Eidam Christopher , Poehlein Anja , Brenner Michael Geovana , Kadlec Kristina , Liesegang Heiko , Brzuszkiewicz Elzbieta , Daniel Rolf , Sweeney Michael T. , Murray Robert W. , Watts Jeffrey L. , Schwarz Stefan
Published: May 2013

Mannheimia haemolytica
is the major bacterial component in the bovine respiratory disease complex, which accounts for considerable economic losses to the cattle industry worldwide. The complete genome sequence of
M. haemolytica
strain 42548 was determined. It has a size of 2.73 Mb and contains 2,888 genes, including several antibiotic resistance genes.
Late onset Ito's nevus
Authors: Resende Cristina , Araújo Catarina , Vieira Ana Paula , Brito Celeste
Published: May 2013

Dermal melanocytoses include a variety of congenital and acquired melanocytic lesions characterised by the presence of multiple spindle-shaped dendritic melanocytes in the dermis. These lesions are commonly found in the skin of Asians, but they can also appear in Caucasians. The Mongolian spot, nevi of Ota and Ito are the most common morphological forms. We report a case of a 24-year-old Caucasian woman presented with a 10-months history of progressive darkening of the right side of her upper back. Cutaneous examination revealed a macular blue-grey hyperpigmentation of the right side of her upper back. Biopsy specimen from the macule showed multiple darkly pigmented, spindle-shaped dendritic melanocytes in the superficial dermis, interstitially arranged between collagen bundles. The diagnosis of nevus of Ito was established. Our patient is maintaining vigilance in dermatology consultation.
Restructuring of the Diabetes Day Centre: a pilot lean project in a tertiary referral centre in the West of Ireland
Authors: McDermott A M , Kidd P , Gately M , Casey R , Burke H , O'Donnell P , Kirrane F , Dinneen S F , O'Brien T
Published: May 2013

Introduction

Diabetes is a chronic disease amenable to management in the community and outpatient setting. The increasing incidence of diabetes places outpatient endocrinology services under pressure to provide a quality service in a timely manner. Our aim was to apply lean thinking to the diabetes clinic in a tertiary referral centre in the West of Ireland to improve flow, as reflected in reduced patient journey times.

Methods

The project lasted 6 months, from January to June 2011. An introductory seminar on lean thinking was arranged to inform and motivate the Diabetes Day Centre staff. Two ‘rapid improvement events’ took place. Value stream mapping (VSM) was the predominant lean tool employed. Patient journeys were mapped and quantified (minutes) using timesheets allocated to each step in the process at baseline, and following intervention. Data were analysed using Minitab V.16.0.

Results

VSM allowed the value-adding and problem-causing steps in the patient journey through the diabetes clinic process to be identified and addressed. Total patient journey time through the clinic was significantly reduced from 118 (±38.02) min to 58 (±18.30) min (p<0.001).

Conclusions

This project reflects the successful application of VSM as a lean tool in a pilot study at our institution as evidenced by improved patient flow and a significant reduction in patient journey time through the clinic. Through the incorporation of Lean into the ethos of the hospital, we have the potential to deliver excellent care in a safe environment and in an efficient manner, while benefiting the patient, employees and tax-payer.
Challenges of managing snakebite envenomation in a deployed setting
Authors: Johnson Christopher , Rimmer J , Mount G , Gurney I , Nicol E D
Published: May 2013

Snake bite envenomation causes a significant health burden globally, especially in austere or resource poor settings. This case series describes envenomation in two adults and two children presenting to the Role 3 Medical Treatment Facility in Camp Bastion, Afghanistan. Each case has similarities with respect to the coagulopathy of envenomation but differs in terms of time delay to presentation and response to treatment, including reactions to antivenom. We discuss the challenges and ethical dilemmas in delayed-presentation snakebite, the diagnosis and treatment of coagulopathy and the role of antivenom and surgical debridement.
Dieulafoy lesion presenting as severe anaemia in a soldier
Authors: Burley Robert MW , Gavrielides I
Published: May 2013

An unusual presentation of severe anaemia in a young soldier is presented. A brief review of the nature of Dieulafoy lesions and treatment and difficulties of managing these in military primary care is considered.
Pneumoperitoneum without visceral trauma: an under-recognised phenomenon after blast injury?
Authors: Bowley Doug M , Gillingham S , Mercer S , Schrager J J , West A
Published: May 2013

Objectives

The management of patients who have sustained blast injuries poses an important challenge for military healthcare professionals. Current military operations are generating large numbers of casualties and modern military healthcare facilities are increasingly using CT scanning to facilitate their management. This small case series serves to draw attention to a rare (or possibly under-reported) phenomenon after blast injury.

Methods and results

We report two patients exposed to blast who had pneumoperitoneum identified by CT scan but who did not have abdominal visceral injury or ballistic peritoneal violation.

Discussion

The use of cross-sectional imaging is leading to the recognition of otherwise occult injury. Military practitioners should be aware of this injury pattern when using CT to help select patients for conservative management after abdominal blast injury.
Angiographic detection of cerebral cavernous malformations with C-arm cone beam CT imaging in three patients
Authors: Radvany Martin G , Rigamonti Daniele , Gailloud Philippe
Published: May 2013

Cerebral cavernous malformations (CMs) are typically not seen during conventional digital subtraction angiography (DSA) and are therefore classically referred to as angiographically occult malformations. We present three cases in which DSA with selective intra-arterial contrast injection in the common carotid artery and C-arm cone beam CT imaging was able to demonstrate a CM. In addition, an associated developmental venous anomaly (DVA) was present in all three cases, although detected by MRI in only one of them. In light of this finding, we suspect that the incidence of DVA associated with CM is probably higher than previously reported.
The ‘one and a half round microcatheterization technique’ for stent-assisted coil embolization of intracranial aneurysm: technical case series
Authors: Miyachi Shigeru , Matsubara Noriaki , Izumi Takashi , Asai Takumi , Yamanouchi Takashi , Ota Keisuke , Oda Keiko , Wakabayashi Toshihiko
Published: May 2013

Background

Stent-assisted coil embolization is useful for wide-necked, large and giant aneurysms, and is effective for avoiding coil herniation. However, the mobility of the microcatheter is often restricted, resulting in deviated or unbalanced coiling. In order to prevent this insufficient coiling, the authors devised a method for microcatheterization, the ‘one and a half round microcatheterization technique’. This technique is based on the formation of a one and a half round loop by the microcatheter along the aneurysmal wall. Furthermore, this technique can be supplemented with the double-catheter technique.

Methods

From July 2010 to July 2012, the authors used this technique for 20 aneurysms in 20 patients (6 men and 14 women; mean age 61.7 years). The one and a half round microcatheterization technique was used alone in 12 cases and was supplemented with the double-catheter technique in eight. The clinical and angiographic results were retrospectively evaluated.

Results

The average aneurysm size was 16.7 mm; 12 aneurysms (60%) were located at the internal carotid artery, 5 (25%) at the basilar artery and 3 (15%) at the vertebral artery. Immediate angiographic results showed complete obliteration in 6 aneurysms (30%) and residual neck in 10 (50%), leaving 4 residual aneurysms (20%). This technique was useful and acceptably safe for packing the aneurysmal sac entirely. During an average follow-up of 20.5 months, 13 of the 18 aneurysms (72%) were stable or had improved, although 3 (16%) required retreatment.

Conclusions

The one and a half round microcatheterization technique provides dense coil packing for stent-assisted embolization of large or giant aneurysms.
Assessment of HIV-related risky behaviour: a comparative study of face-to-face interviews and polling booth surveys in the general population of Cotonou, Benin
Authors: Béhanzin Luc , Diabaté Souleymane , Minani Isaac , Lowndes Catherine M , Boily Marie-Claude , Labbé Annie-Claude , Anagonou Séverin , Zannou Djimon Marcel , Buvé Anne , Alary Michel
Published: May 2013

Objectives

During the 2008 HIV prevalence survey carried out in the general population of Cotonou, Benin, face-to-face interviews (FTFI) were used to assess risky behaviours for HIV and other sexually transmitted infections (STI). We compared sexual behaviours reported in FTFI with those reported in polling booth surveys (PBS) carried out in parallel in an independent random sample of the same population.

Methods

In PBS, respondents grouped by gender and marital status answered simple questions by putting tokens with question numbers in a green box (affirmative answers) or a red box (negative answers). Both boxes were placed inside a private booth. For each group and question, data were gathered together by type of answer. The structured and gender-specific FTFI guided by trained interviewers included all questions asked during PBS. Pearson χ2or Fisher's exact test was used to compare FTFI and PBS according to affirmative answers.

Results

Overall, respondents reported more stigmatised behaviours in PBS than in FTFI: the proportions of married women and men who reported ever having had commercial sex were 17.4% and 41.6% in PBS versus 1.8% and 19.6% in FTFI, respectively. The corresponding proportions among unmarried women and men were 16.1% and 25.5% in PBS versus 3.9% and 13.0% in FTFI, respectively. The proportion of married women who reported having had extramarital sex since marriage was 23.6% in PBS versus 4.6% in FTFI.

Conclusions

PBS are suitable to monitor reliable HIV/STI risk behaviours. Their use should be expanded in behavioural surveillance.
Evaluation of the hormones responsible for the gastrointestinal motility in cattle with displacement of the abomasum; ghrelin, motilin and gastrin
Authors: Ozturk A. S. , Guzel M. , Askar T. K. , Aytekin I.
Published: May 2013

This study provides the evidence of increased serum gastrointestinal motility hormone concentrations including ghrelin, motilin and gastrin in cattle with displacement of abomasum (DA). In this study, 38 cows with DA (21 left DA (LDA) and 17 right DA (RDA)) and 15 healthy controls were included. All cattle with DA were at the stage of postpartum one to eight weeks, and had clinical signs including anorexia, decreased milk yield and scanty, pasty faeces. Serum ghrelin, motilin and gastrin concentrations, and leptin concentration which is a functional antagonist of ghrelin, were determined by ELISA. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma‐glutamyl transferase (GGT), Na, K, Cl, Ca and P concentrations were measured by spectrophotometer. In serum biochemical analysis, increases were seen on the serum ALT, AST and GGT activities; however, serum Na, K, Cl and P concentrations decreased in abomasal displacement compared with the control animals. The serum ghrelin, motilin and gastrin concentrations increased in the cattle with LDA and RDA, as compared with those in the healthy controls. On the other hand, serum leptin concentration decreased in the cattle with DA compared with the controls. Increases in the serum ghrelin, motilin and gastrin concentrations might be attributed to activation of gastrointestinal motility hormones to enhance of gastric emptying in impaired gastric motility and/or outlet occlusion in displaced abomasum.
Teaching dog owners new tricks
Authors: Shepherd Kendal
Published: May 2013

Dog controls without educational support could do more harm than good, says Kendal Shepherd – but, she suggests, there is a solution
SEARCH FAR AND DEEP: FOCUS OF OPEN SEARCH STRATEGY AS DRIVER OF FIRM'S INNOVATION PERFORMANCE
Authors: HENTTONEN KAISA , RITALA PAAVO
Published: May 2013

The effects of open search strategies (i. e., search for firm-external knowledge) on firm-level innovation performance are still ambiguous in the existing literature. We introduce the concepts of focused search strategy and multi-focus search strategy as differentiating factors for a firm. The results of a cross-industrial survey from Finnish markets suggest that applying one focused search strategy intensively generally enhances the firm-level innovation performance. It also seems that emphasizing multiple search strategies intensively improves performance even more, and that the effect becomes stronger, the greater the number of knowledge sources used. Furthermore, the results show that firm-specific technological capabilities have a negative moderating effect in terms of highly focused search strategies, but this diminishes when the focus gets more diverse.
CONCEPTUALIZING THE CO-CREATION OF COMPETITIVE ADVANTAGE IN TECHNOLOGY-INTENSIVE B2B MARKETS: AGENT-BASED MODELING APPROACH
Authors: JÄÄSKELÄINEN MARKUS A. , KORTELAINEN SAMULI , HINKKANEN JUHA J.
Published: May 2013

The importance and challenges of supplier–customer cooperation has been widely recognized in the academic literature but the dynamics of such relationship remain understudied. We do not yet fully understand how customer–supplier relationship should be pursued in order to co-create mutual competitive advantage. Our simulation results show that there are differences in absolute profitability and profit distribution between cooperation partners when moving from individual firm-level management to holistic system-based management. We further find that if the supplier manages cooperation from individualistic perspective it is able to achieve the highest short-term profits by sacrificing the profitability of its customer. However, when the supplier acknowledges the profitability logic of its customer, the long-term overall profitability of the cooperation as a whole, i. e., the system, becomes significantly higher than with opportunistic individually-oriented (short-term) management. In described cases, it is actually profitable for the supplier to limit the distribution of its unique resources (e. g., technology).
PRIVATE–PUBLIC COLLABORATION AND INNOVATION PERFORMANCE: DOES TRAINING MATTER?
Authors: TORUGSA NUTTANEEYA (ANN) , ARUNDEL ANTHONY
Published: May 2013

This study examines, through the theoretical lens of absorptive capacity, how the interaction between investments in R&D and training moderates the influence of collaboration with public research organisations (PROs) on firm innovation performance. Using data for 1,086 innovating firms across all industry sectors in the Australian state of Tasmania in 2010, we find that there is no direct association between collaboration with PROs and firm innovation performance, and the R&D-training interaction plays a significant role in positively moderating such an association. This study contributes to the innovation management literature by demonstrating the importance of the combination of R&D and training in creating absorptive capacity. More importantly, the combination of R&D and training positively influences the successful exploitation of private–public collaboration and promotes innovation performance.
Vigabatrin prevents seizure in swine subjected to hyperbaric hyperoxia
Authors: Hall Aaron A. , Young Colin , Bodo Michael , Mahon Richard T.
Published: May 2013

Oxygen is the most widely used therapeutic strategy to prevent and treat decompression sickness (DCS). Oxygen prebreathe (OPB) eliminated DCS in 20-kg swine after rapid decompression from saturation at 60 feet of seawater (fsw). However, hyperbaric oxygen (HBO) has risks. As oxygen partial pressure increases, so do its toxic effects. Central nervous system (CNS) oxygen toxicity is the most severe side effect, manifesting as seizure. An adjunctive therapeutic is needed to extend OPB strategies to deeper depths and prevent/delay seizure onset. The Food and Drug Administration-approved anti-epileptic vigabatrin has prevented HBO-induced seizures in rats up to 132 fsw. This study aimed to confirm the rat findings in a higher animal model and determine whether acute high-dose vigabatrin evokes retinotoxicity symptoms seen with chronic use clinically in humans. Vigabatrin dose escalation studies were conducted 20-kg swine exposed to HBO at 132 or 165 fsw. The saline group had seizure latencies of 7 and 11 min at 165 and 132 fsw, respectively. Vigabatrin at 180 mg/kg significantly increased latency (13 and 27 min at 165 and 132 fsw, respectively); 250 mg/kg abolished seizure activity at all depths. Functional electroretinogram and histology of the retinas showed no signs of retinal toxicity in any of the vigabatrin=treated animals. In the 250 mg/kg group there was no evidence of CNS oxygen toxicity; however, pulmonary oxygen toxicity limited HBO exposure. Together, the findings from this study show that vigabatrin therapy is efficacious at preventing CNS oxygen toxicity in swine, and a single dose is not acutely associated with retinotoxicity.
Electroretinographic assessment of retinal function at high altitude
Authors: Schatz Andreas , Willmann Gabriel , Fischer M. Dominik , Schommer Kai , Messias André , Zrenner Eberhart , Bartz-Schmidt Karl-Ulrich , Gekeler Florian
Published: May 2013

Although hypoxia plays a key role in the pathophysiology of many common and well studied retinal diseases, little is known about the effects of high-altitude hypoxia on retinal function. The aim of the present study was to assess retinal function during exposure to high-altitude hypoxia using electroretinography (ERG). This work is related to the Tübingen High Altitude Ophthalmology (THAO) study. Electroretinography was performed in 14 subjects in Tübingen, Germany (341 m) and at high altitude at La Capanna Regina Margherita, Italy (4,559 m) using an extended protocol to assess functional integrity of various retinal layers. To place findings in the context of acute mountain sickness, correlations between ERG measurements and oxygen saturation, heart rate, and scores of acute mountain sickness (AMS) were calculated. At high altitude, the maximum response of the scotopic sensitivity function, the implicit times of the a- and b-wave of the combined rod-cone responses, and the implicit times of the photopic negative responses (PhNR) were significantly altered. A-wave slopes and i-waves were significantly decreased at high altitude. The strongest correlation was found for PhNR and O2 saturation ( r = 0.68; P < 0.05). Of all tested correlations, only the photopic b-wave implicit time (10 cd·s/m2) was significantly correlated with severity of AMS ( r = 0.57; P < 0.05). ERG data show that retinal function of inner, outer, and ganglion cell layer is altered at high-altitude hypoxia. Interestingly, the most affected ERG parameters are related to combined rod-cone responses, which indicate that phototransduction and visual processing, especially under conditions of rod-cone interaction, are primarily affected at high altitude.
Potassium dynamics are attenuated in hyperkalemia and a determinant of QT adaptation in exercising hemodialysis patients
Authors: Tran Cao Thach , Bundgaard Henning , Ladefoged Søren Daustrand , Haunsø Stig , Kjeldsen Keld
Published: May 2013

Disturbances in plasma potassium concentration (pK) are well known risk factors for the development of cardiac arrhythmia. The aims of the present study were to evaluate the effect of hemodialysis on exercise pK dynamics and QT hysteresis, and whether QT hysteresis is associated with the pK decrease following exercise. Twenty-two end-stage renal disease patients exercised on a cycle ergometer with incremental work load before and after hemodialysis. ECG was recorded and pK was measured during exercise and recovery. During exercise, pK increased from 5.1 ± 0.2 to 6.1 ± 0.2 mM (mean ± SE; P < 0.0001) before hemodialysis and from 3.8 ± 0.1 to 5.1 ± 0.1 mM ( P < 0.0001) after hemodialysis. After 2 min of recovery, pK had decreased to 5.0 ± 0.2 mM and 4.1 ± 0.1 mM ( P < 0.0001) before and after hemodialysis, respectively. pK increase during exercise was accentuated after hemodialysis. The pK increase was negatively linearly correlated with pK before exercise (β = −0.21, R2= 0.23, P = 0.001). QT hysteresis was negatively linearly correlated with the decrease in pK during recovery (β = −28 ms/mM, R2= 0.36, P = 0.006). Thus, during recovery, low pK was associated with relatively longer QT interval. In conclusion, new major findings are an accentuated increase in pK during exercise after hemodialysis, an attenuated increase in pK in hyperkalemia, and an association between pK and QT interval adaptation during recovery. The acute pK shift after exercise may modulate QT interval adaptation and trigger cardiac arrhythmias.
Bronchodilatory response to deep inspiration in bronchial segments: the effects of stress vs. strain
Authors: Ansell Thomas K. , McFawn Peter K. , Mitchell Howard W. , Noble Peter B.
Published: May 2013

During deep inspirations (DI), a distending force is applied to airway smooth muscle (ASM; i.e., stress) and the muscle is lengthened (i.e., strain), which produces a transient reversal of bronchoconstriction (i.e., bronchodilation). The aim of the present study was to determine whether an increase in ASM stress or the accompanying increase in strain mediates the bronchodilatory response to DI. We used whole porcine bronchial segments in vitro and a servo-controlled syringe pump that applied fixed-transmural pressure (Ptm) or fixed-volume oscillations, simulating tidal breathing and DI. The relationship between ASM stress and strain during oscillation was altered by increasing doses of acetylcholine, which stiffened the airway wall, or by changing the rate of inflation during DI, which utilized the viscous properties of the intact airway. Bronchodilation to DI was positively correlated with ASM strain (range of r values from 0.81 to 0.95) and negatively correlated with stress (range of r values from −0.42 to −0.98). Fast fixed-Ptm DI produced greater bronchodilation than slow DI, despite less ASM strain. Fast fixed-volume DI produced greater bronchodilation than slow DI, despite identical ASM strain. We show that ASM strain, rather than stress, is the critical determinant of bronchodilation and, unexpectedly, that the rate of inflation during DI also impacts on bronchodilation, independent of the magnitudes of either stress or strain.