bluuebunny/crossref_metadata_2025_split huggingface dataset:
GABA promotes survival and axonal regeneration in identifiable descending neurons after spinal cord injury in larval lampreys
Authors: Romaus-Sanjurjo Daniel , Ledo-García Rocío , Fernández-López Blanca , Hanslik Kendra , Morgan Jennifer R. , Barreiro-Iglesias Antón , Rodicio María Celina 
Published: May 2018

AbstractThe poor regenerative capacity of descending neurons is one of the main causes of the lack of recovery after spinal cord injury (SCI). Thus, it is of crucial importance to find ways to promote axonal regeneration. In addition, the prevention of retrograde degeneration leading to the atrophy/death of descending neurons is an obvious prerequisite to activate axonal regeneration. Lampreys show an amazing regenerative capacity after SCI. Recent histological work in lampreys suggested that GABA, which is massively released after a SCI, could promote the survival of descending neurons. Here, we aimed to study if GABA, acting through GABAB receptors, promotes the survival and axonal regeneration of descending neurons of larval sea lampreys after a complete SCI. First, we used in situ hybridization to confirm that identifiable descending neurons of late-stage larvae express the gabab1 subunit of the GABAB receptor. We also observed an acute increase in the expression of this subunit in descending neurons after SCI, which further supported the possible role of GABA and GABAB receptors in promoting the survival and regeneration of these neurons. So, we performed gain and loss of function experiments to confirm this hypothesis. Treatments with GABA and baclofen (GABAB agonist) significantly reduced caspase activation in descending neurons 2 weeks after a complete SCI. Long-term treatments with GABOB (a GABA analogue) and baclofen significantly promoted axonal regeneration of descending neurons after SCI. These data indicate that GABAergic signalling through GABAB receptors promotes the survival and regeneration of descending neurons after SCI. Finally, we used morpholinos against the gabab1 subunit to knockdown the expression of the GABAB receptor in descending neurons. Long-term morpholino treatments caused a significant inhibition of axonal regeneration. This shows that endogenous GABA promotes axonal regeneration after a complete SCI in lampreys by activating GABAB receptors.
Broken translational symmetry at edges of high-temperature superconductors
Authors: Holmvall P. , Vorontsov A. B. , Fogelström M. , Löfwander T. 
Published: May 2018

AbstractFlat bands of zero-energy states at the edges of quantum materials have a topological origin. However, their presence is energetically unfavorable. If there is a mechanism to shift the band to finite energies, a phase transition can occur. Here we study high-temperature superconductors hosting flat bands of midgap Andreev surface states. In a second-order phase transition at roughly a fifth of the superconducting transition temperature, time-reversal symmetry and continuous translational symmetry along the edge are spontaneously broken. In an external magnetic field, only translational symmetry is broken. We identify the order parameter as the superfluid momentum ps, that forms a planar vector field with defects, including edge sources and sinks. The critical points of the vector field satisfy a generalized Poincaré-Hopf theorem, relating the sum of Poincaré indices to the Euler characteristic of the system.
Nanoporous silica gel structures and evolution from reactive force field-based molecular dynamics simulations
Authors: Rimsza J. M. , Du Jincheng 
Published: May 2018

AbstractNanoporous silica-rich gel formed on silicate glass surfaces during dissolution in aqueous environment is critical in elucidating the corrosion mechanisms and the long-term residual dissolution behaviors. Silica gel models were created using two types of methods with reactive force field-based molecular dynamics simulations. The results show that the remnant silica gels created from the ISG bulk structure have a more isolated and closed pore morphology and slightly higher glass network connectivity. This contrasts with the gel structures created by hydrogarnet defect formation that exhibit more connected pore morphologies. The remnant gel structures show lower water diffusivity which was explained by the nano-confinement effect of water molecules due to frequent interactions of water molecules with adjacent silica walls and the more isolated pore morphology in the remnant gel structures. These results reveal the complexity in terms of micro and atomic structures of these silica gels, and both structure features have impact on water transport in the gel layer hence the passivating effect that controls the long-term dissolution behavior of these glasses.
Lumbosacral spinal cord epidural stimulation improves voiding function after human spinal cord injury
Authors: Herrity A. N. , Williams C. S. , Angeli C. A. , Harkema S. J. , Hubscher C. H. 
Published: May 2018

AbstractDeficits in urologic function after spinal cord injury (SCI) manifest both as a failure to store and empty, greatly impacting daily life. While current management strategies are necessary for urological maintenance, they oftentimes are associated with life-long side effects. Our objective was to investigate the efficacy of spinal cord epidural stimulation (scES) as a promising therapy to improve bladder control after SCI. A bladder mapping study was undertaken for sixteen sessions over the course of four months in an individual with chronic, motor complete SCI. Varying combinations of stimulating cathode electrodes were initially tested during filling cystometry resulting in the identification of an effective configuration for reflexive bladder emptying at the caudal end of the electrode array. Subsequent systematic testing of different frequencies at a fixed stimulus intensity and pulse width yielded lowest post-void residual volumes at 30 Hz. These stimulation parameters were then tested in four additional research participants and found to also improve reflexive voiding efficiency. Taken together with SCI studies on step, stand, voluntary motor control and cardiovascular regulation, these findings further corroborate that scES has an all-encompassing potential to increase the central state of excitability, allowing for the control of multiple body functions, including the urological system.
Hexagonal MoTe2 with Amorphous BN Passivation Layer for Improved Oxidation Resistance and Endurance of 2D Field Effect Transistors
Authors: Sirota Benjamin , Glavin Nicholas , Krylyuk Sergiy , Davydov Albert V. , Voevodin Andrey A. 
Published: May 2018

AbstractEnvironmental and thermal stability of two-dimensional (2D) transition metal dichalcogenides (TMDs) remains a fundamental challenge towards enabling robust electronic devices. Few-layer 2H-MoTe2 with an amorphous boron nitride (a-BN) covering layer was synthesized as a channel for back-gated field effect transistors (FET) and compared to uncovered MoTe2. A systematic approach was taken to understand the effects of heat treatment in air on the performance of FET devices. Atmospheric oxygen was shown to negatively affect uncoated MoTe2 devices while BN-covered FETs showed considerably enhanced chemical and electronic characteristic stability. Uncapped MoTe2 FET devices, which were heated in air for one minute, showed a polarity switch from n- to p-type at 150 °C, while BN-MoTe2 devices switched only after 200 °C of heat treatment. Time-dependent experiments at 100 °C showed that uncapped MoTe2 samples exhibited the polarity switch after 15 min of heat treatment while the BN-capped device maintained its n-type conductivity for the maximum 60 min duration of the experiment. X-ray photoelectron spectroscopy (XPS) analysis suggests that oxygen incorporation into MoTe2 was the primary doping mechanism for the polarity switch. This work demonstrates the effectiveness of an a-BN capping layer in preserving few-layer MoTe2 material quality and controlling its conductivity type at elevated temperatures in an atmospheric environment.
Expression and localization of CB1R, NAPE-PLD, and FAAH in the vervet monkey nucleus accumbens
Authors: Kucera Ryan , Bouskila Joseph , Elkrief Laurent , Fink-Jensen Anders , Palmour Roberta , Bouchard Jean-François , Ptito Maurice 
Published: May 2018

AbstractExtensive rodent literature suggests that the endocannabinoid (eCB) system present in the nucleus accumbens (NAc) modulates dopamine (DA) release in this area. However, expression patterns of the cannabinoid receptor type 1 (CB1R), the synthesizing enzyme N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD), and the degradation enzyme fatty acid amide hydrolase (FAAH) in the NAc have not yet been described in non-human primates. The goal of this study is therefore to characterize the expression and localization of the eCB system within the NAc of vervet monkeys (Chlorocebus sabaeus) using Western blots and immunohistochemistry. Results show that CB1R, NAPE-PLD, and FAAH are expressed across the NAc rostrocaudal axis, both in the core and shell. CB1R, NAPE-PLD, and FAAH are localized in medium spiny neurons (MSNs) and fast-spiking GABAergic interneurons (FSIs). Dopaminergic projections and astrocytes did not express CB1R, NAPE-PLD, or FAAH. These data show that the eCB system is present in the vervet monkey NAc and supports its role in the primate brain reward circuit.
The dynamic interplay between acute psychosocial stress, emotion and autobiographical memory
Authors: Sheldon Signy , Chu Sonja , Nitschke Jonas P. , Pruessner Jens C. , Bartz Jennifer A. 
Published: May 2018

AbstractAlthough acute psychosocial stress can impact autobiographical memory retrieval, the nature of this effect is not entirely clear. One reason for this ambiguity is because stress can have opposing effects on the different stages of autobiographical memory retrieval. We addressed this issue by testing how acute stress affects three stages of the autobiographical memory retrieval – accessing, recollecting and reconsolidating a memory. We also investigate the influence of emotion valence on this effect. In a between-subjects design, participants were first exposed to an acute psychosocial stressor or a control task. Next, the participants were shown positive, negative or neutral retrieval cues and asked to access and describe autobiographical memories. After a three to four day delay, participants returned for a second session in which they described these autobiographical memories. During initial retrieval, stressed participants were slower to access memories than were control participants; moreover, cortisol levels were positively associated with response times to access positively-cued memories. There were no effects of stress on the amount of details used to describe memories during initial retrieval, but stress did influence memory detail during session two. During session two, stressed participants recovered significantly more details, particularly emotional ones, from the remembered events than control participants. Our results indicate that the presence of stress impairs the ability to access consolidated autobiographical memories; moreover, although stress has no effect on memory recollection, stress alters how recollected experiences are reconsolidated back into memory traces.
Population resequencing reveals candidate genes associated with salinity adaptation of the Pacific oyster Crassostrea gigas
Authors: She Zhicai , Li Li , Meng Jie , Jia Zhen , Que Huayong , Zhang Guofan 
Published: May 2018

AbstractThe Pacific oyster Crassostrea gigas is an important cultivated shellfish. As a euryhaline species, it has evolved adaptive mechanisms responding to the complex and changeable intertidal environment that it inhabits. To investigate the genetic basis of this salinity adaptation mechanism, we conducted a genome-wide association study using phenotypically differentiated populations (hyposalinity and hypersalinity adaptation populations, and control population), and confirmed our results using an independent population, high-resolution melting, and mRNA expression analysis. For the hyposalinity adaptation, we determined 24 genes, including Cg_CLCN7 (chloride channel protein 7) and Cg_AP1 (apoptosis 1 inhibitor), involved in the ion/water channel and transporter mechanisms, free amino acid and reactive oxygen species metabolism, immune responses, and chemical defence. Three SNPs located on these two genes were significantly differentiated between groups, as was Cg_CLCN7. For the hypersalinity adaptation, the biological process for positive regulating the developmental process was enriched. Enriched gene functions were focused on transcriptional regulation, signal transduction, and cell growth and differentiation, including calmodulin (Cg_CaM) and ficolin-2 (Cg_FCN2). These genes and polymorphisms possibly play an important role in oyster hyposalinity and hypersalinity adaptation. They not only further our understanding of salinity adaptation mechanisms but also provide markers for highly adaptable oyster strains suitable for breeding.
Effect of HIV-1 Tat on the formation of the mitotic spindle by interaction with ribosomal protein S3
Authors: Kim Jiyoung , Kim Yeon-Soo 
Published: May 2018

AbstractHuman immunodeficiency virus type 1 (HIV-1) Tat, an important regulator of viral transcription, interacts with diverse cellular proteins and promotes or inhibits cell proliferation. Here, we show that ribosomal protein S3 (RPS3) plays an important role in mitosis through an interaction with α-tubulin and that Tat binds to and inhibits the localization of RPS3 in the mitotic spindle during mitosis. RPS3 colocalized with α-tubulin around chromosomes in the mitotic spindle. Depletion of RPS3 promoted α-tubulin assembly, while overexpression of RPS3 impaired α-tubulin assembly. Depletion of RPS3 resulted in aberrant mitotic spindle formation, segregation failure, and defective abscission. Moreover, ectopic expression of RPS3 rescued the cell proliferation defect in RPS3-knockdown cells. HIV-1 Tat interacted with RPS3 through its basic domain and increased the level of RPS3 in the nucleus. Expression of Tat caused defects in mitotic spindle formation and chromosome assembly in mitosis. Moreover, the localization of RPS3 in the mitotic spindle was disrupted when HIV-1 Tat was expressed in HeLa and Jurkat cells. These results suggest that Tat inhibits cell proliferation via an interaction with RPS3 and thereby disrupts mitotic spindle formation during HIV-1 infection. These results might provide insight into the mechanism underlying lymphocyte pathogenesis during HIV-1 infection.
Impact of stress in ICP‐CVD SiNx passivation films on the leakage current in AlGaN/GaN HEMTs
Authors: Cho S.‐J. , Li X. , Guiney I. , Floros K. , Hemakumara D. , Wallis D.J. , Humphreys C. , Thayne I.G. 
Published: May 2018

The impact of the stress in room temperature inductively coupled plasma chemical vapour deposited (ICP‐CVD) SiNx surface passivation layers on off‐state drain (IDS‐off) and gate leakage currents (IGS) in AlGaN/GaN high electron mobility transistors (HEMTs) is reported. IDS‐off and IGS in 2 μm gate length devices were reduced by up to four orders of magnitude to ∼10 pA/mm using a compressively stressed bilayer SiNx passivation scheme. In addition, Ion/Ioff of ∼1011 and subthreshold slope of 68 mV/dec were obtained using this strain engineered surface passivation approach.
Self‐balanced non‐isolated hybrid modular DC–DC converter for medium‐voltage DC grids
Authors: Elserougi Ahmed A. , Massoud Ahmed M. , Abdelsalam Ibrahim , Ahmed Shehab 
Published: May 2018

Here, a new bi‐directional hybrid modular non‐isolated DC–DC converter is proposed where it consists of a boost converter (BC) fed from the high‐voltage (HV) side. At the BC output stage, a certain number of half bridge submodules (HB‐SMs) is connected across the BC switch. During the turn‐on period of BC switch, the HB‐SMs are connected sequentially to the low‐voltage (LV) side, which results in charging/discharging their capacitors from/into the LV side. While, during the turn‐off period, the LV side is bypassed and the HB‐SMs capacitors are connected in series across the BC output stage, which results in discharging/charging them into/from the HV side. The power flow is controlled in both directions by controlling the duty cycle. The proposed configuration provides self‐balancing operation thanks to the sequential connection of HB‐SMs capacitors, and it also provides the ability to operate with high conversion ratios. Illustration and analysis of the proposed converter and its closed‐loop controller are presented. A full design of the values and ratings of the involved components are presented. Simulation study for a 2.5 MW (25 kV/10 kV) DC–DC converter is presented. Finally, experimental results for a downscaled prototype are presented for validation.
Average covering number for some graphs
Authors: Doğan Durgun D. , Bagatarhan Ali 
Published: May 2018

The interconnection networks are modeled by means of graphs to determine the reliability and vulnerability. There are lots of parameters that are used to determine vulnerability. The average covering number is one of them which is denoted by $ \overline{\beta }(G)$, where G is simple, connected and undirected graph of order n ≥ 2. In a graph G = (V(G), E(G)) a subset

$ {S}_v\subseteq V(G)$

of vertices is called a cover set of G with respect to v or a local covering set of vertex v, if each edge of the graph is incident to at least one vertex of Sv. The local covering number with respect to v is the minimum cardinality of among the Sv sets and denoted by βv. The average covering number of a graph G is defined as

β̅(G) = 1/|v(G)| ∑ν∈v(G)βν

In this paper, the average covering numbers of kth power of a cycle
$ {C}_n^k$ and Pn □ Pm, Pn □ Cm, cartesian product of Pn and Pm, cartesian product of Pn and Cm are given, respectively.
Time Dependence of Whole Blood Aggregation in Response to Platelet Activating Factor (PAF)
Authors: Taylor R R , Strophair J , Sturm M , Vandongen R , Beilin L J 
Published: May 2018

SummaryThe aggregation/adhesion response to platelet activating factor (PAF) was studied in diluted whole blood by impedance aggregometry. The extent of aggregation varied directly with the interval between blood sampling and aggregation measurement over the first 30 minutes from sampling, then remained stable for the next 60 minutes of observation. This is an effect opposite to that described for aggregation to PAF in platelet rich plasma which, however, cannot be studied soon after sampling. Time dependence of aggregation is important and comparative measurements should be made during the period of stable aggregability.
Predictors of Knee Arthrofibrosis and Outcomes after Arthroscopic Lysis of Adhesions following Ligamentous Reconstruction: A Retrospective Case–Control Study with Over Two Years' Average Follow-Up
Authors: Bodendorfer Blake M. , Keeling Laura E. , Michaelson Evan M. , Shu Henry T. , Apseloff Nicholas A. , Spratt James D. , Malone Patrick S. , Argintar Evan H. 
Published: May 2018

AbstractArthrofibrosis can be a devastating complication after ligamentous knee reconstruction. Beyond early range of motion (ROM), manipulation under anesthesia (MUA) and arthroscopic lysis of adhesions (LOAs) are the most frequently employed interventions for the condition. There is a paucity of data regarding predictive factors of arthrofibrosis requiring MUA and LOA, and even less data regarding changes in validated patient-reported outcome measures following the procedure. A retrospective case–control study was performed at an academic, urban Level I trauma center of patients that developed arthrofibrosis requiring MUA and LOA following ligamentous reconstruction. The indication for LOA was failure to achieve a 90° arc of ROM by 6 weeks. Seventeen cases and 141 controls were identified. Follow-up for cases was 26.9 ± 17.1 months (mean ± standard deviation). Time from initial reconstruction to LOA was 75.2 ± 27.9 days. Cases had higher body mass indices by a mean of 2.9 (p = 0.024). The most significant risk factors for stiffness were concomitant anterior cruciate ligament, posterior cruciate ligament, and posterolateral corner/lateral collateral ligament injury (odds ratio [OR], 17.08), knee dislocation (OR, 12.84), and use of an external fixator (OR, 12.81, 95% confidence interval [CI], 3.03–54.20) (all p < 0.0026). Mean Knee Injury and Osteoarthritis Outcome Scores, Western Ontario and McMaster Universities Osteoarthritis Indices, and International Knee Documentation Committee scores improved by 47.5, 50.5, and 47.3% (all p < 0.0038), respectively. All patients reported improvement in pain, with maximum daily pain scores improving by a mean of 4.1 points on the Numeric Pain Rating Scale (p < 0.001). Mean ROM arc improved by 38.8° (p < 0.001). All 17 cases were satisfied with the procedure. Twelve cases (70.59%) reported a full return to preinjury level of activity. No factors were identified that predicted success from the procedure, likely due to inadequate sample size. Arthrofibrosis following knee injury and ligamentous reconstruction can be predicted by the severity of injury and early intervention with MUA and arthroscopic LOA can lead to a satisfactory outcome for the patient.
Contrast-Enhanced Ultrasound and Near-Infrared Spectroscopy of the Neonatal Bowel: Novel, Bedside, Noninvasive, and Radiation-Free Imaging for Early Detection of Necrotizing Enterocolitis
Authors: Al-Hamad Suzanne , Hackam David , Goldstein Seth , Huisman Thierry , Darge Kassa , Hwang Misun 
Published: May 2018

AbstractDespite extensive research and improvements in the field of neonatal care, the morbidity and mortality associated with necrotizing enterocolitis (NEC) have remained unchanged over the past three decades. Early detection of ischemia and necrotic bowel is vital in improving morbidity and mortality associated with NEC; however, strategies for predicting and preventing NEC are lacking. Contrast-enhanced ultrasound (CEUS) and near-infrared spectroscopy (NIRS) are novel techniques in pediatrics that have been proven as safe modalities. CEUS has benefits over conventional ultrasound (US) by its improved real-time evaluation of the micro- and macrovascularities of normally and abnormally perfused tissue. US has been implemented as a useful adjunct to X-ray for earlier evaluation of NEC. NIRS is another noninvasive technique that has shown promise in improving early detection of NEC. The purpose of this article is to review the current understanding of changes in bowel perfusion in NEC, discuss the accuracy of abdominal US in detecting NEC, and explain how the use of CEUS and NIRS will enhance the precise and early detection of altered/pathological bowel wall perfusion in the initial development and course of NEC.