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An electron gun that can produce MHz repetition rates and nanosecond pulses is described. The gun uses a Pierce grid in combination with an anode to extract electrons from a tungsten filament cathode. The electrons emerging from the anode are accelerated and focused using two triple-aperture lenses to form a beam. By applying a high slew rate grid pulse that transitions through the extraction voltage region of the grid/anode combination, pulses of electrons are produced from the gun that have temporal widths less than 5 ns. The pulsed beams are produced at both the rising and falling edges of the driving pulse. The characteristics of the emerging electron beams have been determined using an (e, 2e) coincidence spectrometer, and examples where they are used for time of flight decay measurements are presented. [ABSTRACT FROM AUTHOR]

Purpose: To confirm that CrCEST in muscle exhibits a slow‐exchanging process, and to obtain high‐resolution amide, creatine (Cr), and phosphocreatine (PCr) maps of skeletal muscle using a POlynomial and Lorentzian Line‐shape Fitting (PLOF) CEST at 3T. Methods: We used dynamic changes in PCr/CrCEST of mouse hindlimb before and after euthanasia to assign the Cr and PCr CEST peaks in the Z‐spectrum at 3T and to obtain the optimum saturation parameters. Segmented 3D EPI was employed to obtain multi‐slice amide, PCr, and Cr CEST maps of human skeletal muscle. Subsequently, the PCrCEST maps were calibrated using the PCr concentrations determined by 31P MRS. Results: A comparison of the Z‐spectra in mouse hindlimb before and after euthanasia indicated that CrCEST is a slow‐exchanging process in muscle (<150.7 s−1). This allowed us to simultaneously extract PCr/CrCEST signals at 3T using the PLOF method. We determined optimal B1 values ranging from 0.3 to 0.6 μT for CrCEST in muscle and 0.3–1.2 μT for PCrCEST. For the study on human calf muscle, we determined an optimum saturation time of 2 s for both PCr/CrCEST (B1 = 0.6 μT). The PCr/CrCEST using 3D EPI were found to be comparable to those obtained using turbo spin echo (TSE). (3D EPI/TSE PCr: (2.6 ± 0.3) %/(2.3 ± 0.1) %; Cr: (1.3 ± 0.1) %/(1.4 ± 0.07) %). Conclusions: Our study showed that in vivo CrCEST is a slow‐exchanging process. Hence, amide, Cr, and PCr CEST in the skeletal muscle can be mapped simultaneously at 3T by PLOF CEST. [ABSTRACT FROM AUTHOR]

Purpose: To assess the feasibility of CEST‐based creatine (Cr) mapping in brain at 3T using the guanidino (Guan) proton resonance. Methods: Wild type and knockout mice with guanidinoacetate N‐methyltransferase deficiency and low Cr and phosphocreatine (PCr) concentrations in the brain were used to assign the Cr and protein‐based arginine contributions to the GuanCEST signal at 2.0 ppm. To quantify the Cr proton exchange rate, two‐step Bloch–McConnell fitting was used to fit the extracted CrCEST line‐shape and multi‐B1 Z‐spectral data. The pH response of GuanCEST was simulated to demonstrate its potential for pH mapping. Results: Brain Z‐spectra of wild type and guanidinoacetate N‐methyltransferase deficiency mice show a clear Guan proton peak at 2.0 ppm at 3T. The CrCEST signal contributes ∼23% to the GuanCEST signal at B1 = 0.8 μT, where a maximum CrCEST effect of 0.007 was detected. An exchange rate range of 200–300 s−1 was estimated for the Cr Guan protons. As revealed by the simulation, an elevated GuanCEST in the brain is observed when B1 is less than 0.4 μT at 3T, when intracellular pH reduces by 0.2. Conversely, the GuanCEST decreases when B1 is greater than 0.4 μT with the same pH drop. Conclusions: CrCEST mapping is possible at 3T, which has potential for detecting intracellular pH and Cr concentration in brain. [ABSTRACT FROM AUTHOR]

As part of a 3-wk intersession workshop funded by a National Science Foundation Expeditions in Computing award, 15 undergraduate students from the City University of New York collaborated on a study aimed at characterizing the voltage dynamics and arrhythmogenic behavior of cardiac cells for a broad range of physiologically relevant conditions using an in silico model. The primary goal of the workshop was to cultivate student interest in computational modeling and analysis of complex systems by introducing them through lectures and laboratory activities to current research in cardiac modeling and by engaging them in a hands-on research experience. The success of the workshop lay in the exposure of the students to active researchers and experts in their fields, the use of hands-on activities to communicate important concepts, active engagement of the students in research, and explanations of the significance of results as the students generated them. The workshop content addressed how spiral waves of electrical activity are initiated in the heart and how different parameter values affect the dynamics of these reentrant waves. Spiral waves are clinically associated with tachycardia, when the waves remain stable, and with fibrillation, when the waves exhibit breakup. All in silico experiments were conducted by simulating a mathematical model of cardiac cells on graphics processing units instead of the standard central processing units of desktop computers. This approach decreased the run time for each simulation to almost real time, thereby allowing the students to quickly analyze and characterize the simulated arrhythmias. Results from these simulations, as well as some of the background and methodology taught during the workshop, is presented in this article along with the programming code and the explanations of simulation results in an effort to allow other teachers and students to perform their own demonstrations, simulations, and studies. (Contains 9 figures, 2 tables and 1 footnote.)

Many school psychologists focus their interpretation on composite scores from intelligence test batteries designed to measure the broad abilities from the Cattell-Horn-Carroll theory. The purpose of this study was to investigate the general factor loadings and specificity of the broad ability composite scores from one such intelligence test battery, the Woodcock-Johnson III Tests of Cognitive Abilities Normative Update (Woodcock, McGrew, Schrank, & Mather, 2007). Results from samples beginning at age 4 and continuing through age 60 indicate that Comprehension-Knowledge, Long-Term Retrieval, and Fluid Reasoning appear to be primarily measures of the general factor at many ages. In contrast, Visual-Spatial Thinking, Auditory Processing, and Processing Speed appear to be primarily measures of specific abilities at most ages. We offer suggestions for considering both the general factor and specific abilities when interpreting Cattell-Horn-Carroll broad ability composite scores. (Contains 2 tables and 7 footnotes.)

In soybean, asynaptic and desynaptic mutants lead to abnormal meiosis and fertility reduction. Several male-sterile, female-sterile mutants have been identified and studied in soybean, however, some of these mutants have not been mapped to locations on soybean chromosomes. The objectives of this study were to molecularly map five male-sterile, female-sterile genes (st2, st4, st5, st6, and st7) in soybean and compare the map locations of these genes with already mapped sterility genes. Microsatellite markers were used in bulked segregant analyses to locate all five malesterile, female-sterile genes to soybean chromosomes, and markers from the corresponding chromosomes were used on F2 populations to generate genetic linkage maps. The st2, st4, st5, st6, and st7 genes were located on molecular linkage group (MLG) B1 (chromosome 11), MLG D1a (chromosome 01), MLG F (chromosome 13), MLG B2 (chromosome 14), and D1b (chromosome 02), respectively. The st2, st4, st5, st6, and st7 genes were flanked to 10.3 (~399 kb), 6.3 (~164 kb), 3.9 (~11.8 Mb), 11.0 (~409 kb), and 5.3 cM (~224 kb), and the flanked regions contained 57,17, 362, 52, and 17 predicted genes, respectively. Future characterization of candidate genes should facilitate identification of the male- and female-fertility genes, which may provide vital insights on structure and function of genes involved in the reproductive pathway in soybean. Key words: Glycine max, sterility, simple sequence repeat, genetic linkage map, male-sterile female-sterile. Chez le soya, des mutants asynaptiques et desynaptiques presentent des anomalies meiotiques et une reduction de la fertilite. Plusieurs mutants presentant une sterilite male et femelle ont ete identifies et etudies, mais certains de ceux-ci n'ont pas ete situes sur les chromosomes du soya. Les objectifs de ce travail etaient de realiser la cartographie de cinq genes de sterilite male et femelle (st2, st4, st5, st6 et st7) chez le soya et de comparer la position de ces genes avec celle d'autres genes de sterilite deja positionnes. Des marqueurs microsatellites ont ete employes dans le cadre d'analyses de segregants en melange afin d'assigner une position chromosomique aux cinq genes de sterilite male et femelle. Les marqueurs situes sur ces chromosomes ont ete employes sur des populations F2 afin de generer des cartes genetiques. Les genes st2, st4, st5, st6 et st7 ont ete assignes respectivement aux groupes de liaison moleculaires (MLG) B1 (chromosome 11), MLG D1a (chromosome 01), MLG F (chromosome 13), MLG B2 (chromosome 14) et MLG D1b (chromosome 2). Les genes st2, st4, st5, st6 et st7 ont ete assignes a des intervalles de 10,3 (~399 kb), 6,3 (~164 kb), 3,9 (~11,8 Mb), 11,0 (~409 kb) et 5,3 cM (~224 kb); ces intervalles contenaient respectivement 57,17, 362, 52 et 17 genes predits. Une future caracterisation de genes candidats devrait faciliter l'identification des genes de fertilite male et femelle, laquelle fournira un eclairage important sur la structure et la fonction des genes impliques dans la reproduction chez le soya. [Traduit par la Redaction] Mots-cles: Glycine max, sterilite, sequence simple repetee, carte genetique, sterilite male et femelle., Introduction In soybean, asynaptic and desynaptic mutants lead to abnormal meiosis and fertility reduction. This is caused by abnormal pairing of chromosomes during the first meiotic prophase, also known as [...]

Distal radius fractures account for 18 percent of all fractures in the elderly age group. It is estimated that the yearly cost of treatment for distal radius fractures approaches $240 million. The frequency of fractures will continue to increase with the aging population. The operative treatment of distal radius fractures has changed dramatically with the advent of the fixed-angle volar plate. Volar plating allows stable internal fixation which permits early return of function. A common and serious complication of volar plating of distal radius fractures is rupture of the flexor pollicis longus tendon. We report a case of a late rupture of the flexor pollicis longus tendon six years following plating of a distal radius fracture. The pathology and treatment options for flexor tendon ruptures are discussed. Guidelines for patient surveillance following distal radius plating are reviewed. [ABSTRACT FROM AUTHOR]

Mild traumatic brain injury (TBI) from focal head impact is the most common form of TBI in humans. Animal models, however, typically use direct impact to the exposed dura or skull, or blast to the entire head. We present a detailed characterization of a novel overpressure blast system to create focal closed-head mild TBI in mice. A high-pressure air pulse limited to a 7.5 mm diameter area on the left side of the head overlying the forebrain is delivered to anesthetized mice. The mouse eyes and ears are shielded, and its head and body are cushioned to minimize movement. This approach creates mild TBI by a pressure wave that acts on the brain, with minimal accompanying head acceleration-deceleration. A single 20-psi blast yields no functional deficits or brain injury, while a single 25-40 psi blast yields only slight motor deficits and brain damage. By contrast, a single 50-60 psi blast produces significant visual, motor, and neuropsychiatric impairments and axonal damage and microglial activation in major fiber tracts, but no contusive brain injury. This model thus reproduces the widespread axonal injury and functional impairments characteristic of closed-head mild TBI, without the complications of systemic or ocular blast effects or head acceleration that typically occur in other blast or impact models of closed-skull mild TBI. Accordingly, our model provides a simple way to examine the biomechanics, pathophysiology, and functional deficits that result from TBI and can serve as a reliable platform for testing therapies that reduce brain pathology and deficits. [ABSTRACT FROM AUTHOR]

The article discusses how the attorney-client privilege in the U.S. is under assault in the insurance bad faith context and reports its impact on the privilege for insurance companies as a target party.

We have developed a focal blast model of closed-head mild traumatic brain injury (TBI) in mice. As true for individuals that have experienced mild TBI, mice subjected to 50-60 psi blast show motor, visual and emotional deficits, diffuse axonal injury and microglial activation, but no overt neuron loss. Because microglial activation can worsen brain damage after a concussive event and because microglia can be modulated by their cannabinoid type 2 receptors (CB2), we evaluated the effectiveness of the novel CB2 receptor inverse agonist SMM-189 in altering microglial activation and mitigating deficits after mild TBI. In vitro analysis indicated that SMM-189 converted human microglia from the pro-inflammatory M1 phenotype to the pro-healing M2 phenotype. Studies in mice showed that daily administration of SMM-189 for two weeks beginning shortly after blast greatly reduced the motor, visual, and emotional deficits otherwise evident after 50-60 psi blasts, and prevented brain injury that may contribute to these deficits. Our results suggest that treatment with the CB2 inverse agonist SMM-189 after a mild TBI event can reduce its adverse consequences by beneficially modulating microglial activation. These findings recommend further evaluation of CB2 inverse agonists as a novel therapeutic approach for treating mild TBI. [ABSTRACT FROM AUTHOR]

Emotional disorders are a common outcome from mild traumatic brain injury (TBI) in humans, but their pathophysiological basis is poorly understood. We have developed a mouse model of closed-head blast injury using an air pressure wave delivered to a small area on one side of the cranium, to create mild TBI. We found that 20-psi blasts in 3-month-old C57BL/6 male mice yielded no obvious behavioral or histological evidence of brain injury, while 25-40 psi blasts produced transient anxiety in an open field arena but little histological evidence of brain damage. By contrast, 50-60 psi blasts resulted in anxiety-like behavior in an open field arena that became more evident with time after blast. In additional behavioral tests conducted 2-weeks after blast, 50-60 psi mice also demonstrated increased acoustic startle, perseverance of learned fear, and enhanced contextual fear, as well as depression-like behavior and diminished prepulse inhibition. We found no evident cerebral pathology, but did observe scattered axonal degeneration in brain sections from 50 to 60 psi mice 3-8weeks after blast. Thus, the TBI caused by single 50-60 psi blasts in mice exhibits the minimal neuronal loss coupled to "diffuse" axonal injury characteristic of human mild TBI. A reduction in the abundance of a subpopulation of excitatory projection neurons in basolateral amygdala enriched in Thy1 was, however, observed. The reported link of this neuronal population to fear suppression suggests their damage by mild TBI may contribute to the heightened anxiety and fearfulness observed after blast in our mice. Our overpressure air blast model of concussion in mice will enable further studies of the mechanisms underlying the diverse emotional deficits seen after mild TBI. [ABSTRACT FROM AUTHOR]

Abstract: In diploid segregation, each alternative allele has a 50% chance of being passed on to the offspring. Mutations in genes involved in the process of meiotic division or early stages of reproductive cell development can affect allele frequency in the gametes. In addition, competition among gametes and differential survival rates of gametes can lead to segregation distortion. In a recent transformation study, a male-sterile, female-sterile (MSFS) mutant was identified in the soybean cultivar, Williams. The mutant in heterozygous condition segregated 3 fertile:1 sterile in the progeny confirming monogenic inheritance. To map the lesion, we generated an F2 mapping population by crossing the mutant (in heterozygous condition) with Minsoy (PI 27890). The F2 progeny showed strong segregation distortion against the MSFS phenotype. The objectives of our study were to molecularly map the gene responsible for sterility in the soybean genome, to determine if the MSFS gene is a result of T-DNA insertion during Agrobacterium-mediated transformation, and to map the region that showed distorted segregation. The fertility/sterility locus was mapped to molecular linkage group (MLG) D1a (chromosome Gm01) using bulked segregant analysis. The closest marker, Satt531, mapped 9.4cM from the gene. Cloning of insertion sites for T-DNA in the mutant plants revealed that there are two copies of T-DNA in the genome. Physical locations of these insertion sites do not correlate with the map location of the MSFS gene, suggesting that MSFS mutation may not be associated with T-DNA insertions. Segregation distortion was most extreme at or around the st_A06-2/6 locus suggesting that sterility and segregation distortion are tightly linked attributes. Our results cue that the distorted segregation may be due to a gamete elimination system. [Copyright &y& Elsevier]

The article analyzes new legislation and its effectiveness with regards to the vision of having a high speed rail system in America. It offers a history of passenger rail, high speed rail in various parts of the world and the ability of American Recovery and Reinvestment Act of 2009 (ARRA) to create a high speed U.S. rail system and its challenges. It also notes benefits that could be gained by America from high speed rail, the environmental impact and the Clean Air Policy, the federal funding and creation of a federal high speed rail administration.

Graphical abstract Highlights • Uptake2 regulates extracellular 5-HT in the CeA. • Serotonin regulation by amygdala uptake2 is stress dependent. • Normetanephrine and corticosterone interact with stress to increase 5-HT in the CeA. Abstract Organic cation transporter 3 (OCT3) is a corticosterone-sensitive, low-affinity, high-capacity transporter. This transporter functions, in part, to clear monoamines, including serotonin (5-HT), from the extracellular space. The central nucleus of the amygdala (CeA) is an important structure controlling fear- and anxiety-related behaviors. The CeA has reciprocal connections with brainstem nuclei containing monoaminergic systems, including serotonergic systems arising from the dorsal raphe nucleus, which are thought to play an important role in modulation of CeA-mediated behavioral responses. Organic cation transporter 3 (OCT3) is expressed in the CeA, but little is known about the role of OCT3 within the CeA in modulating serotonergic signaling. We hypothesized that inhibition of OCT3-mediated transport in the CeA during restraint stress would increase extracellular 5-HT. In Experiment 1 , rats received unilateral reverse dialysis of either corticosterone or normetanephrine, which interfere with OCT3-mediated transport, into the CeA under home cage control conditions. In Experiment 2 , rats received unilateral reverse dialysis of corticosterone, normetanephrine, or vehicle into the CeA, while undergoing a 40-min period of restraint stress. Infusion of these drugs had no effect on extracellular concentrations of 5-HT during home cage control conditions, but, in contrast, markedly increased extracellular concentrations of 5-HT during restraint stress, relative to vehicle-treated controls. These findings suggest a role for OCT3 in the CeA in control of serotonergic signaling during stressful conditions. [ABSTRACT FROM AUTHOR]

Transcriptional control of the hgl5 gene of Entamoeba histolytica is mediated through an unusual core promoter composed of TATA, GAAC and Initiator elements. In the hgl5 promoter the GAAC element (AATGAACT) determines the site and rate of transcription initiation. Here we tested the role of the GAAC element in transcription activation from upstream regulatory elements (UREs) in the hgl5 promoter. We also examined the function of the GAAC element in the ferredoxin (fdx) promoter and characterized the protein binding to the GAAC element. Electrophoretic mobility shift assays (EMSA) demonstrated that the GAAC region is necessary for higher-order nuclear protein complex assembly. The function of the GAAC element in transcription activation mediated by UREs revealed that mutation of the GAAC element did not affect transcription activation mediated by the hgl5 URE4 but abrogated activation by the hgl5 URE3. We compared the role of the GAAC elements in the hgl5 and fdx promoters. Competitive gel shift assays were consistent with the same nuclear protein binding to the GAAC elements in both genes. Mutation of the GAAC element in the fdx gene decreased reporter gene expression, however, in contrast to hgl5 gene, had no effect on the site of transcription initiation. These results support a role for the GAAC element in assembly of nuclear proteins at the core promoter and in transcription activation mediated by URE3. The differing effect on transcription initiation in the hgl5 and fdx genes upon mutation of the GAAC element suggests a context-dependence of the GAAC-binding protein in gene expression. [Copyright &y& Elsevier]