bluuebunny/crossref_metadata_2025 huggingface dataset:
Nearly s-semipermutable subgroups and p-nilpotency
Authors: Li Changwen , Yi Xiaolan , Yu Xiaolong
Published: June 2014

We say that a subgroup H of a group G is nearly s-semipermutable in G provided G has an s-permutable subgroup T such that HT is s-permutable in G and H ∩ T ≤ HssG, where HssG is the subgroup of H generated by all those subgroups of H which are s-semipermutable in G. In this paper, we investigate the influence of near s-semipermutability of some subgroups on the p-nilpotency of finite groups.
On a conjecture on sparse binomial-type polynomials by Brown, Dilcher and Manna
Authors: Gawronski Wolfgang , Neuschel Thorsten
Published: June 2014

We prove a conjecture by Brown, Dilcher and Manna on the asymptotic behavior of sparse binomial-type polynomials arising naturally in a graph-theoretical context in connection with the expected number of independent sets of a graph.
Quantum codes over rings
Authors: Guenda Kenza , Gulliver T. Aaron
Published: June 2014

This paper considers the construction of quantum error correcting codes from linear codes over finite commutative Frobenius rings. We extend the Calderbank–Shor–Steane (CSS) construction to these rings. Further, quantum codes are extended to matrix product codes. Quantum codes over 𝔽pk are also obtained from linear codes over rings using the generalized Gray map.
Generalized Fermat equations: A miscellany
Authors: Bennett Michael A. , Chen Imin , Dahmen Sander R. , Yazdani Soroosh
Published: June 2014

This paper is devoted to the generalized Fermat equation xp + yq = zr, where p, q and r are integers, and x, y and z are nonzero coprime integers. We begin by surveying the exponent triples (p, q, r), including a number of infinite families, for which the equation has been solved to date, detailing the techniques involved. In the remainder of the paper, we attempt to solve the remaining infinite families of generalized Fermat equations that appear amenable to current techniques. While the main tools we employ are based upon the modularity of Galois representations (as is indeed true with all previously solved infinite families), in a number of cases we are led via descent to appeal to a rather intricate combination of multi-Frey techniques.
Global properties of a cell mediated immunity in HIV infection model with two classes of target cells and distributed delays
Authors: Elaiw A. M. , Abukwaik R. M. , Alzahrani E. O.
Published: June 2014

In this paper, we study the global properties of a human immunodeficiency virus (HIV) infection model with cytotoxic T lymphocytes (CTL) immune response. The model is a six-dimensional that describes the interaction of the HIV with two classes of target cells, CD4+T cells and macrophages. The infection rate is given by saturation functional response. Two types of distributed time delays are incorporated into the model to describe the time needed for infection of target cell and virus replication. Using the method of Lyapunov functional, we have established that the global stability of the model is determined by two threshold numbers, the basic infection reproduction number R0and the immune response activation number [Formula: see text]. We have proven that if R0≤ 1, then the uninfected steady state is globally asymptotically stable (GAS), if [Formula: see text], then the infected steady state without CTL immune response is GAS, and if [Formula: see text], then the infected steady state with CTL immune response is GAS.
On Gromov's positive scalar curvature conjecture for duality groups
Authors: Dranishnikov Alexander
Published: June 2014

We prove the inequality [Formula: see text] for the macroscopic dimension of the universal covers [Formula: see text] of almost spin n-manifolds M with positive scalar curvature whose fundamental group π1(M) is a virtual duality group that satisfies the coarse Baum–Connes conjecture.
Gröbner–Shirshov bases for commutative algebras with multiple operators and free commutative Rota–Baxter algebras
Authors: Qiu Jianjun
Published: June 2014

In this paper, the Composition-Diamond lemma for commutative algebras with multiple operators is established. As applications, the Gröbner–Shirshov bases and linear bases of free commutative Rota–Baxter algebra, free commutative λ-differential algebra and free commutative λ-differential Rota–Baxter algebra are given, respectively. Consequently, these three free algebras are constructed directly by commutative Ω-words.
Histone deacetylase 8 regulates cortactin deacetylation and contraction in smooth muscle tissues
Authors: Li Jia , Chen Shu , Cleary Rachel A. , Wang Ruping , Gannon Olivia J. , Seto Edward , Tang Dale D.
Published: June 2014

Histone deacetylases (HDACs) are a family of enzymes that mediate nucleosomal histone deacetylation and gene expression. Some members of the HDAC family have also been implicated in nonhistone protein deacetylation, which modulates cell-cycle control, differentiation, and cell migration. However, the role of HDACs in smooth muscle contraction is largely unknown. Here, HDAC8 was localized both in the cytoplasm and the nucleus of mouse and human smooth muscle cells. Knockdown of HDAC8 by lentivirus-encoding HDAC8 shRNA inhibited force development in response to acetylcholine. Treatment of smooth muscle tissues with HDAC8 inhibitor XXIV (OSU-HDAC-44) induced relaxation of precontracted smooth muscle tissues. In addition, cortactin is an actin-regulatory protein that undergoes deacetylation during migration of NIH 3T3 cells. In this study, acetylcholine stimulation induced cortactin deacetylation in mouse and human smooth muscle tissues, as evidenced by immunoblot analysis using antibody against acetylated lysine. Knockdown of HDAC8 by RNAi or treatment with the inhibitor attenuated cortactin deacetylation and actin polymerization without affecting myosin activation. Furthermore, expression of a charge-neutralizing cortactin mutant inhibited contraction and actin dynamics during contractile activation. These results suggest a novel mechanism for the regulation of smooth muscle contraction. In response to contractile stimulation, HDAC8 may mediate cortactin deacetylation, which subsequently promotes actin filament polymerization and smooth muscle contraction.
Flow shear stress enhances intracellular Ca2+ signaling in pulmonary artery smooth muscle cells from patients with pulmonary arterial hypertension
Authors: Song Shanshan , Yamamura Aya , Yamamura Hisao , Ayon Ramon J. , Smith Kimberly A. , Tang Haiyang , Makino Ayako , Yuan Jason X.-J.
Published: June 2014

An increase in cytosolic Ca2+ concentration ([Ca2+]cyt) in pulmonary arterial smooth muscle cells (PASMC) is a major trigger for pulmonary vasoconstriction and an important stimulus for pulmonary arterial medial hypertrophy in patients with idiopathic pulmonary arterial hypertension (IPAH). Vascular smooth muscle cells (SMC) sense the blood flow shear stress through interstitial fluid driven by pressure or direct exposure to blood flow in case of endothelial injury. Mechanical stimulus can increase [Ca2+]cyt. Here we report that flow shear stress raised [Ca2+]cyt in PASMC, while the shear stress-mediated rise in [Ca2+]cyt and the protein expression level of TRPM7 and TRPV4 channels were significantly greater in IPAH-PASMC than in normal PASMC. Blockade of TRPM7 by 2-APB or TRPV4 by Ruthenium red inhibited shear stress-induced rise in [Ca2+]cyt in normal and IPAH-PASMC, while activation of TRPM7 by bradykinin or TRPV4 by 4αPDD induced greater increase in [Ca2+]cyt in IPAH-PASMC than in normal PASMC. The bradykinin-mediated activation of TRPM7 also led to a greater increase in [Mg2+]cyt in IPAH-PASMC than in normal PASMC. Knockdown of TRPM7 and TRPV4 by siRNA significantly attenuated the shear stress-mediated [Ca2+]cyt increases in normal and IPAH-PASMC. In conclusion, upregulated mechanosensitive channels (e.g., TRPM7, TRPV4, TRPC6) contribute to the enhanced [Ca2+]cyt increase induced by shear stress in PASMC from IPAH patients. Blockade of the mechanosensitive cation channels may represent a novel therapeutic approach for relieving elevated [Ca2+]cyt in PASMC and thereby inhibiting sustained pulmonary vasoconstriction and pulmonary vascular remodeling in patients with IPAH.
Degradation mechanism of a Golgi-retained distal renal tubular acidosis mutant of the kidney anion exchanger 1 in renal cells
Authors: Chu Carmen Y. , King Jennifer , Berrini Mattia , Rumley Alina C. , Apaja Pirjo M. , Lukacs Gergely L. , Alexander R. Todd , Cordat Emmanuelle
Published: June 2014

Distal renal tubular acidosis (dRTA) can be caused by mutations in the SLC4A1 gene encoding the anion exchanger 1 (AE1). Both recessive and dominant mutations result in mistrafficking of proteins, preventing them from reaching the basolateral membrane of renal epithelial cells, where their function is needed. In this study, we show that two dRTA mutants are prematurely degraded. Therefore, we investigated the degradation pathway of the kidney AE1 G701D mutant that is retained in the Golgi. Little is known about degradation of nonnative membrane proteins from the Golgi compartments in mammalian cells. We show that the kidney AE1 G701D mutant is polyubiquitylated and degraded by the lysosome and the proteosome. This mutant reaches the plasma membrane, where it is endocytosed and degraded by the lysosome via a mechanism dependent on the peripheral quality control machinery. Furthermore, we show that the function of the mutant is rescued at the cell surface upon inhibition of the lysosome and incubation with a chemical chaperone. We conclude that modulating the peripheral quality control machinery may provide a novel therapeutic option for treatment of patients with dRTA due to a Golgi-retained mutant.
Microtubules are required for efficient epithelial tight junction homeostasis and restoration
Authors: Glotfelty Lila G. , Zahs Anita , Iancu Catalin , Shen Le , Hecht Gail A.
Published: June 2014

Epithelial tight junctions are critical for creating a barrier yet allowing paracellular transport. Although it is well established that the actin cytoskeleton is critical for preserving the dynamic organization of the tight junction and maintaining normal tight junction protein recycling, contributions of microtubules to tight junction organization and function remain undefined. The aim of this study is to determine the role of microtubules in tight junction homeostasis and restoration. Our data demonstrate that occludin traffics on microtubules and that microtubule disruption perturbs tight junction structure and function. Microtubules are also shown to be required for restoring barrier function following Ca2+ chelation and repletion. These processes are mediated by proteins participating in microtubule minus-end-directed trafficking but not plus-end-directed trafficking. These studies show that microtubules participate in the preservation of epithelial tight junction structure and function and play a vital role in tight junction restoration, thus expanding our understanding of the regulation of tight junction physiology.
SMAD3 augments FoxO3-induced MuRF-1 promoter activity in a DNA-binding-dependent manner
Authors: Bollinger Lance M. , Witczak Carol A. , Houmard Joseph A. , Brault Jeffrey J.
Published: June 2014

Muscle-specific RING finger-1 (MuRF-1), a ubiquitin ligase and key regulator of proteasome-dependent protein degradation, is highly expressed during skeletal muscle atrophy. The transcription factor forkhead box O3 (FoxO3) induces MuRF-1 expression, but the direct role of other major atrophy-related transcription factors, such as SMAD3, is largely unknown. The goal of this study was to determine whether SMAD3 individually regulates, or with FoxO3 coordinately regulates, MuRF-1 expression. In cultured myotubes or human embryonic kidney cells, MuRF-1 mRNA content and promoter activity were increased by FoxO3 but not by SMAD3 overexpression. However, FoxO3 and SMAD3 coexpression synergistically increased MuRF-1 mRNA and promoter activity. Mutation of the SMAD-binding element (SBE) in the proximal MuRF-1 promoter or overexpression of a SMAD3 DNA-binding mutant attenuated FoxO3-dependent MuRF-1 promoter activation, showing that SMAD binding to DNA is required for optimal activation of FoxO3-induced transcription of MuRF-1. Using chromatin immunoprecipitation, SMAD3 DNA binding increased FoxO3 abundance and SBE mutation reduced FoxO3 abundance on the MuRF-1 promoter. Furthermore, SMAD3 overexpression dose-dependently increased FoxO3 protein content, and coexpression of FoxO3 and SMAD3 synergistically increased FoxO-dependent gene transcription [assessed with a FoxO response element (FRE)-driven reporter]. Collectively, these results show that SMAD3 regulates transcription of MuRF-1 by increasing FoxO3 binding at a conserved FRE-SBE motif within the proximal promoter region, and by increasing FoxO3 protein content and transcriptional activity. These data are the first to indicate that two major transcription factors regulating protein degradation, FoxO3 and SMAD3, converge to coordinately and directly regulate transcription of MuRF-1.
Effects of peripheral and spinal κ-opioid receptor stimulation on the exercise pressor reflex in decerebrate rats
Authors: Copp Steven W. , Stone Audrey J. , Yamauchi Katsuya , Kaufman Marc P.
Published: June 2014

The exercise pressor reflex is greater in rats with ligated femoral arteries than it is in rats with freely perfused femoral arteries. The exaggerated reflex in rats with ligated arteries is attenuated by stimulation of μ-opioid and δ-opioid receptors on the peripheral endings of thin-fiber muscle afferents. The effect of stimulation of κ-opioid receptors on the exercise pressor reflex is unknown. We tested the hypothesis that stimulation of κ-opioid receptors attenuates the exercise pressor reflex in rats with ligated, but not freely perfused, femoral arteries. The pressor responses to static contraction were compared before and after femoral arterial or intrathecal injection of the κ-opioid receptor agonist U62066 (1, 10, and 100 μg). Femoral arterial injection of U62066 did not attenuate the pressor responses to contraction in either group of rats. Likewise, intrathecal injection of U62066 did not attenuate the pressor response to contraction in rats with freely perfused femoral arteries. In contrast, intrathecal injection of 10 and 100 μg of U62066 attenuated the pressor response to contraction in rats with ligated femoral arteries, an effect that was blocked by prior intrathecal injection of the κ-opioid receptor antagonist nor-binaltorphimine. In rats with ligated femoral arteries, the pressor response to stimulation of peripheral chemoreceptors by sodium cyanide was not changed by intrathecal U62066 injections, indicating that these injections had no direct effect on the sympathetic outflow. We conclude that stimulation of spinal, but not peripheral, κ-opioid receptors attenuates the exaggerated exercise pressor reflex in rats with ligated femoral arteries.
Apolipoprotein A-I mimetic peptide 4F attenuates kidney injury, heart injury, and endothelial dysfunction in sepsis
Authors: Moreira Roberto S. , Irigoyen Maria , Sanches Talita R. , Volpini Rildo A. , Camara Niels O. S. , Malheiros Denise M. , Shimizu Maria H. M. , Seguro Antonio C. , Andrade Lucia
Published: June 2014

Kidney injury, heart injury, and cytokine-induced vascular hyperpermeability are associated with high rates of morbidity and mortality in sepsis. Although the mechanism remains unknown, apolipoprotein A-I (apoA-I) mimetic peptide 4F reduces inflammation and protects HDL levels, which are reduced in sepsis. We hypothesized that 4F also protects kidneys and hearts in a rat model of cecal ligation and puncture (CLP). We divided Wistar rats into groups: sham-operated (control), CLP, and CLP+4F (10 mg/kg body wt ip, 6 h after CLP). At 24 h post-CLP, we evaluated cardiac function, mean arterial pressure (MAP), heart rate (HR), baroreflex sensitivity, total cholesterol, LDL, HDL, serum cytokines, and inulin clearance. We performed immunoblotting for protein regulators of vascular permeability (Slit2 and Robo4) and endothelial nitric oxide synthase (eNOS) in kidney tissue. We evaluated heart mitochondria with electron microscopy. Although there was no difference in MAP, the HR was significantly higher in CLP rats than in control and CLP+4F rats. In CLP+4F rats, baroreflex sensitivity and cardiac function were completely protected from the effects of CLP, as was glomerular filtration; heart mitochondria morphology was improved; sepsis-induced changes in serum cholesterol, LDL, HDL, and apoA-I were less common; all cytokines were lower than in CLP rats; and expression of Slit2, Robo4, and eNOS was completely restored. Administration of 4F inhibits inflammatory responses and strengthens the vascular barrier, protecting kidneys and hearts in an HDL-dependent manner. To determine the extent of the protective effect of 4F, further studies are needed.
Evidence for pericyte origin of TSC-associated renal angiomyolipomas and implications for angiotensin receptor inhibition therapy
Authors: Siroky Brian J. , Yin Hong , Dixon Bradley P. , Reichert Ryan J. , Hellmann Anna R. , Ramkumar Thiruvamoor , Tsuchihashi Zenta , Bunni Marlene , Dillon Joshua , Bell P. Darwin , Sampson Julian R. , Bissler John J.
Published: June 2014

Nearly all patients with tuberous sclerosis complex (TSC) develop renal angiomyolipomas, although the tumor cell of origin is unknown. We observed decreased renal angiomyolipoma development in patients with TSC2- polycystic kidney disease 1 deletion syndrome and hypertension that were treated from an early age with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers compared with patients who did not receive this therapy. TSC-associated renal angiomyolipomas expressed ANG II type 1 receptors, platelet-derived growth factor receptor-β, desmin, α-smooth muscle actin, and VEGF receptor 2 but did not express the adipocyte marker S100 or the endothelial marker CD31. Sera of TSC patients exhibited increased vascular mural cell-secreted peptides, such as VEGF-A, VEGF-D, soluble VEGF receptor 2, and collagen type IV. These findings suggest that angiomyolipomas may arise from renal pericytes. ANG II treatment of angiomyolipoma cells in vitro resulted in an exaggerated intracellular Ca2+response and increased proliferation, which were blocked by the ANG II type 2 receptor antagonist valsartan. Blockade of ANG II signaling may have preventative therapeutic potential for angiomyolipomas.
Blockade of cysteine-rich protein 61 attenuates renal inflammation and fibrosis after ischemic kidney injury
Authors: Lai Chun-Fu , Lin Shuei-Liong , Chiang Wen-Chih , Chen Yung-Ming , Wu Vin-Cent , Young Guang-Huar , Ko Wen-Jo , Kuo Min-Liang , Tsai Tun-Jun , Wu Kwan-Dun
Published: June 2014

Emerging data have suggested that acute kidney injury (AKI) is often incompletely repaired and can lead to chronic kidney disease (CKD), which is characterized by tubulointerstitial inflammation and fibrosis. However, the underlying mechanisms linking AKI to CKD remain obscure. The present study aimed to investigate the role of cysteine-rich protein 61 (Cyr61) after unilateral kidney ischemia-reperfusion injury (IRI) in mice. After IRI, increased expression of Cyr61 was detected, predominately in the proximal tubular epithelium. This was confirmed by in vitro experiments, which showed that hypoxia stimulated Cyr61 expression in cultured proximal tubular epithelial cells. The proinflammatory property of Cyr61 was indicated by its ability to upregulate monocyte chemoattractant protein-1 and IL-6. Additionally, we found elevated urinary Cyr61 excretion in patients with AKI. Notably, treatment of mice with an anti-Cyr61 antibody attenuated the upregulation of kidney monocyte chemoattractant protein-1, IL-6, IL-1β, and macrophage inflammatory protein-2 and reduced the infiltration of F4/80-positive macrophages on days 7 and 14 after IRI. In addition, blockade of Cyr61 reduced the mRNA expression of collagen, transforming growth factor-β, and plasminogen activator inhibitor-I as well as the degree of collagen fibril accumulation, as evaluated by picrosirius red staining, and levels of α-smooth muscle actin proteins by day 14. Concurrently, in the treated group, peritubular microvascular density was more preserved on day 14. We conclude that Cyr61 blockade inhibits the triad of inflammation, interstitial fibrosis, and capillary rarefaction after severe ischemic AKI. The results of this study expand the knowledge of the mechanisms underlying the AKI-to-CKD transition and suggest that Cyr61 is a potential therapeutic target.
Basal forebrain dynamics during a tactile discrimination task
Authors: Thomson Eric , Lou Jason , Sylvester Kathryn , McDonough Annie , Tica Stefani , Nicolelis Miguel A.
Published: June 2014

The nucleus basalis (NB) is a cholinergic neuromodulatory structure that projects liberally to the entire cortical mantle and regulates information processing in all cortical layers. Here, we recorded activity from populations of single units in the NB as rats performed a whisker-dependent tactile discrimination task. Over 80% of neurons responded with significant modulation in at least one phase of the task. Such activity started before stimulus onset and continued for seconds after reward delivery. Firing rates monotonically increased with reward magnitude during the task, suggesting that NB neurons are not indicating the absolute deviation from expected reward amounts. Individual neurons also encoded significant amounts of information about stimulus identity. Such robust coding was not present when the same stimuli were delivered to lightly anesthetized animals, suggesting that the NB neurons contain a sensorimotor, rather than purely sensory or motor, representation of the environment. Overall, these results support the hypothesis that neurons in the NB provide a value-laden representation of the sensorimotor state of the animal as it engages in significant behavioral tasks.
Pulsed infrared radiation excites cultured neonatal spiral and vestibular ganglion neurons by modulating mitochondrial calcium cycling
Authors: Lumbreras Vicente , Bas Esperanza , Gupta Chhavi , Rajguru Suhrud M.
Published: June 2014

Cochlear implants are currently the most effective solution for profound sensorineural hearing loss, and vestibular prostheses are under development to treat bilateral vestibulopathies. Electrical current spread in these neuroprostheses limits channel independence and, in some cases, may impair their performance. In comparison, optical stimuli that are spatially confined may result in a significant functional improvement. Pulsed infrared radiation (IR) has previously been shown to elicit responses in neurons. This study analyzes the response of neonatal rat spiral and vestibular ganglion neurons in vitro to IR (wavelength = 1,863 nm) using Ca2+imaging. Both types of neurons responded consistently with robust intracellular Ca2+([Ca2+]i) transients that matched the low-frequency IR pulses applied (4 ms, 0.25–1 pps). Radiant exposures of ∼637 mJ/cm2resulted in continual neuronal activation. Temperature or [Ca2+] variations in the media did not alter the IR-evoked transients, ruling out extracellular Ca2+involvement or primary mediation by thermal effects on the plasma membrane. While blockage of Na+, K+, and Ca2+plasma membrane channels did not alter the IR-evoked response, blocking of mitochondrial Ca2+cycling with CGP-37157 or ruthenium red reversibly inhibited the IR-evoked [Ca2+]itransients. Additionally, the magnitude of the IR-evoked transients was dependent on ryanodine and cyclopiazonic acid-dependent Ca2+release. These results suggest that IR modulation of intracellular calcium cycling contributes to stimulation of spiral and vestibular ganglion neurons. As a whole, the results suggest selective excitation of neurons in the IR beam path and the potential of IR stimulation in future auditory and vestibular prostheses.
Quantifying the signals contained in heterogeneous neural responses and determining their relationships with task performance
Authors: Pagan Marino , Rust Nicole C.
Published: June 2014

The responses of high-level neurons tend to be mixtures of many different types of signals. While this diversity is thought to allow for flexible neural processing, it presents a challenge for understanding how neural responses relate to task performance and to neural computation. To address these challenges, we have developed a new method to parse the responses of individual neurons into weighted sums of intuitive signal components. Our method computes the weights by projecting a neuron's responses onto a predefined orthonormal basis. Once determined, these weights can be combined into measures of signal modulation; however, in their raw form these signal modulation measures are biased by noise. Here we introduce and evaluate two methods for correcting this bias, and we report that an analytically derived approach produces performance that is robust and superior to a bootstrap procedure. Using neural data recorded from inferotemporal cortex and perirhinal cortex as monkeys performed a delayed-match-to-sample target search task, we demonstrate how the method can be used to quantify the amounts of task-relevant signals in heterogeneous neural populations. We also demonstrate how these intuitive quantifications of signal modulation can be related to single-neuron measures of task performance ( d′).
Enhanced attentional gain as a mechanism for generalized perceptual learning in human visual cortex
Authors: Byers Anna , Serences John T.
Published: June 2014

Learning to better discriminate a specific visual feature (i.e., a specific orientation in a specific region of space) has been associated with plasticity in early visual areas ( sensory modulation) and with improvements in the transmission of sensory information from early visual areas to downstream sensorimotor and decision regions ( enhanced readout). However, in many real-world scenarios that require perceptual expertise, observers need to efficiently process numerous exemplars from a broad stimulus class as opposed to just a single stimulus feature. Some previous data suggest that perceptual learning leads to highly specific neural modulations that support the discrimination of specific trained features. However, the extent to which perceptual learning acts to improve the discriminability of a broad class of stimuli via the modulation of sensory responses in human visual cortex remains largely unknown. Here, we used functional MRI and a multivariate analysis method to reconstruct orientation-selective response profiles based on activation patterns in the early visual cortex before and after subjects learned to discriminate small offsets in a set of grating stimuli that were rendered in one of nine possible orientations. Behavioral performance improved across 10 training sessions, and there was a training-related increase in the amplitude of orientation-selective response profiles in V1, V2, and V3 when orientation was task relevant compared with when it was task irrelevant. These results suggest that generalized perceptual learning can lead to modified responses in the early visual cortex in a manner that is suitable for supporting improved discriminability of stimuli drawn from a large set of exemplars.
Discrete Planning Unit Look-Ahead Velocity Control Strategy and Parallelization Research Based on GPU
Authors: Cao Yunan , Ye Peiqing , Zhang Qinjian , Li Jianyong
Published: June 2014

During the machining of complicated curves and surfaces, the massive microsegments are generated. The microsegments are inputted into numerical control system (CNC) to process the velocity planning and high-velocity interpolation. This whole procedure is the core algorithm of CNC. During the procedure of velocity planning, the look-ahead iterative calculation is used for several specified future microsegments and the calculation quantity is very large. Additionally, the CNC is a typical hard real-time system. Every interpolation step must be finished in specified interpolation period, so the high calculating ability of CPU is needed. The concept of GPU is quite different from the traditional CPU. It has a very strong parallel computing ability. In this project, the GPU technology is introduced into CNC algorithm. The parallel structure model is constructed by CUDA, and a discrete planning unit look-ahead velocity control strategy is proposed. The GPU parallel computing mechanism of massive microsegments is discussed and, based on the research, a high-performance velocity planning algorithm is presented. This research result can highly raise the velocity planning and interpolation efficiency. This brand new solution can help improve the performance of CNC system dramatically.
Interaction of Refractory Dibenzothiophenes and Polymerizable Structures
Authors: Rivera Jose L. , Navarro-Santos Pedro , Guerra-Gonzalez Roberto , Lima Enrique
Published: June 2014

We carried out first principles calculations to show that polymerizable structures containing hydroxyl (alcoholic chain) and amino groups are suitable to form stable complexes with dibenzothiophene (DBT) and its alkyl derivates. These sulfur pollutants are very difficult to eliminate through traditional catalytic processes. Spontaneous and exothermic interactions at 0 K primarily occur through the formation of stable complexes of organosulfur molecules with monomeric structures by hydrogen bonds. The bonds are formed between the sulfur atom and the hydrogen of the hydroxyl group; additional hydrogen bonds are formed between the hydrogen atoms of the organosulfur molecule and the nitrogen atoms of the monomers. We vary the number of methylene groups in the alcoholic chain containing the hydroxyl group of the monomer and find that the monomeric structure with four methylene groups has the best selectivity towards the interaction with the methyl derivates with reference to the interaction with DBT. Even this study does not consider solvent and competitive adsorption effects; our results show that monomeric structures containing amino and hydroxyl groups can be used to develop adsorbents to eliminate organosulfur pollutants from oil and its derivates.
Ethanol at Low Concentration Attenuates Diabetes Induced Lung Injury in Rats Model
Authors: Hu Jun-Feng , Zhang Guan-Jun , Wang Lei , Kang Pin-Fang , Li Jun , Wang Hong-Ju , Gao Qin , Chen Yu-Qing
Published: June 2014

To observe the changes of lung injury when diabetic rats were treated with low concentration of ethanol (EtOH) and analyze the related mechanisms, male Sprague-Dawley (SD) rats were divided into control, diabetic (DM), and EtOH+DM groups. Diabetic rat was mimicked by injection of streptozotocin intraperitoneally. Fasting blood glucose (FBG) level, lung weight (LW), body weight (BW), and LW/BW were measured. The changes of lung tissue and Type II alveolar cell were detected. Pulmonary malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were measured; meanwhile, ALDH2 mRNA and protein expressions were detected by RT-PCR and western blotting, respectively. Compared with control group, in DM group, SOD activity was decreased; FBG level, LW/BW, MDA content, ALDH2 mRNA, and protein expressions were decreased. Compared with DM group, in EtOH+DM group, SOD activity, ALDH2 mRNA, and protein expressions were increased; LW/BW and MDA content were decreased. The structures of lung tissue and lamellar bodies were collapsed in DM group; the injury was attenuated in EtOH+DM group. Our findings suggested that, in diabetic rat, pulmonary ALDH2 expression was decreased accompanying lung injury. EtOH at low concentration decreased diabetes induced lung injury through activating ALDH2 expression.
Targeting the Glutamatergic System to Treat Pathological Gambling: Current Evidence and Future Perspectives
Authors: Pettorruso Mauro , De Risio Luisa , Martinotti Giovanni , Di Nicola Marco , Ruggeri Filippo , Conte Gianluigi , Di Giannantonio Massimo , Janiri Luigi
Published: June 2014

Pathological gambling or gambling disorder has been defined by the DSM-5 as a behavioral addiction. To date, its pathophysiology is not completely understood and there is no FDA-approved treatment for gambling disorders. Glutamate is the principal excitatory neurotransmitter in the nervous system and it has been recently involved in the pathophysiology of addictive behaviors. In this paper, we review the current literature on a class of drugs that act as modulating glutamate system in PG. A total of 19 studies have been included, according to inclusion and exclusion criteria. Clinical trial and case series using glutamatergic drugs (N-acetylcysteine, memantine, amantadine, topiramate, acamprosate, baclofen, gabapentin, pregabalin, and modafinil) will be presented to elucidate the effectiveness on gambling behaviors and on the related clinical dimensions (craving, withdrawal, and cognitive symptoms) in PG patients. The results have been discussed to gain more insight in the pathophysiology and treatment of PG. In conclusion, manipulation of glutamatergic neurotransmission appears to be promising in developing improved therapeutic agents for the treatment of gambling disorders. Further studies are required. Finally, we propose future directions and challenges in this research area.
Hopf Bifurcation in a Cobweb Model with Discrete Time Delays
Authors: Gori Luca , Guerrini Luca , Sodini Mauro
Published: June 2014

We develop a cobweb model with discrete time delays that characterise the length of production cycle. We assume a market comprised of homogeneous producers that operate as adapters by taking the (expected) profit-maximising quantity as a target to adjust production and consumers with a marginal willingness to pay captured by an isoelastic demand. The dynamics of the economy is characterised by a one-dimensional delay differential equation. In this context, we show that (1) if the elasticity of market demand is sufficiently high, the steady-state equilibrium is locally asymptotically stable and (2) if the elasticity of market demand is sufficiently low, quasiperiodic oscillations emerge when the time lag (that represents the length of production cycle) is high enough.
Research on Blade Thickness Influencing Pump as Turbine
Authors: Yang Sun-Sheng , Wang Chao , Chen Kai , Yuan Xin
Published: June 2014

Research on the efficiency improvement of pump as turbine (PAT) is inadequate. Blade thickness is an important geometry parameter in blade design. To explore effects of blade thickness on the influence of PAT, numerical research on three different specific speeds of PATs with different blade thickness was carried out. Their performance changes with blade thickness were presented. Besides, the variations of hydraulic loss distribution with increasing blade thickness were performed. Theoretical analysis gives a reasonable explanation for the performance change. Results show thatPAT's flow versus efficiency curve ( Q-η) is lowered; flow versus head ( Q-H) curve and flow versus power ( Q-P) curve are increased with increasing blade thickness. The increase of Q-P is mainly attributed to the increase of theoretical head caused by increasing blockage of impeller inlet area. Hydraulic loss distribution analysis indicates that the total hydraulic loss within PAT is increased with increasing blade thickness. The increase of Q-H curve is a combined effect of the increase in theoretical head and the total hydraulic loss. The decrease of efficiency with increasing blade thickness indicates that the blade thickness of PAT should be as thin as possible if its strength could be met.
Autoimmune Hemolytic Anemia Induced by Levofloxacin
Authors: Sheikh-Taha Marwan , Frenn Pascale
Published: June 2014

Drug-induced autoimmune hemolytic anemia is a rare condition. We report the case of a 32-year-old white female who presented to the emergency department with generalized fatigue, fever, and jaundice. The patient reported using levofloxacin few days prior to presentation for urinary tract infection. The patient had evidence of hemolytic anemia with a hemoglobin of 6.7 g/dL which dropped to 5 g/dL on day 2, the direct Coombs test was positive, indirect bilirubin was 5.5 mg/dL, and LDH was 1283 IU/L. Further testing ruled out autoimmune disease, lymphoma, and leukemia as etiologies for the patient’s hemolytic anemia. Levofloxacin was immediately stopped with a gradual hematologic recovery within few days.
Experimental Study on Characteristics of Oil Particle Distribution in Water-Gelled Crude Oil Two-Phase Flow System
Authors: Xiaoyan Liu , Zhonghua Wang , Lijun Liu , Chuanyan Wu , Qianjun Mao
Published: June 2014

The conventional gathering and transportation mode of heating the produced fluid of oil wells with hot water or steam may result in excessive energy consumption. In order to perform the unheated transportation, the idea of hydraulic suspension transport of the gelled crude oil is proposed based on the actual production of Daqing Oilfield, and the experimental system is established to test characteristics of oil particle distribution which have an important effect on the hydraulic suspension transportation. In the experiment, the image of gelled crude oil particle distribution was obtained in a horizontal pipe with inner diameter of 0.053 m, and then the law of particle distribution was investigated by the theoretical model. The results showed that the gelled crude oil hydraulic suspension transport could be achieved without any chemical reagent when the gelled crude oil was transformed into particles and dispersedly suspended in water. The results also showed that the gelled oil particles of 0–4 mm in size accounted for 92% or more of all particles, and the percentage of gelled crude oil particles of a size of 4 mm gradually increased with the increasing mixed flow rate.
Some New Transformation Properties of the Nielsen Generalized Polylogarithm
Authors: Shang Nina , Feng Qinghua , Qin Huizeng
Published: June 2014

Many of the properties of Nielsen generalized polylogarithmSn,p(z), for example, the special value and the transformation formulas, play important roles in the computation of higher order radiative corrections in quantum electrodynamics. In this paper, some transformation formulas ofz→p(z),p(z)=1-z,1/z,1/(1-z),z/(z-1), and(1-z)/zare obtained. In particular, the last three transformation formulas are new results so far in the literature. By use of these transformation formulas presented, new fast algorithms for Nielsen generalized polylogarithmSn,p(z)can be designed. Forsn,p=Sn,p(1), a new recurrence formula is also given. The identities and the calculation ofσn,pandan,pare also investigated.
A New Surgical Technique of Pancreaticoduodenectomy with Splenic Artery Resection for Ductal Adenocarcinoma of the Pancreatic Head and/or Body Invading Splenic Artery: Impact of the Balance between Surgical Radicality and QOL to Avoid Total Pancreatectomy
Authors: Desaki Ryosuke , Mizuno Shugo , Tanemura Akihiro , Kishiwada Masashi , Murata Yasuhiro , Azumi Yoshinori , Kuriyama Naohisa , Usui Masanobu , Sakurai Hiroyuki , Tabata Masami , Isaji Shuji
Published: June 2014

For pancreatic ductal adenocarcinoma (PDAC) of the head and/or body invading the splenic artery (SA), we developed a new surgical technique of proximal subtotal pancreatectomy with splenic artery and vein resection, so-called pancreaticoduodenectomy with splenic artery resection (PD-SAR). We retrospectively reviewed a total of 84 patients with curative intent pancreaticoduodenectomy (PD) for PDAC of the head and/or body. These 84 patients were classified into the two groups: conventional PD (n=66) and PD-SAR (n=18). Most patients were treated by preoperative chemoradiotherapy (CRT). Postoperative MDCT clearly demonstrated enhancement of the remnant pancreas at 1 and 6 months in all patients examined. Overall survival rates were very similar between PD and PD-SAR (3-year OS: 23.7% versus 23.1%,P=0.538), despite the fact that the tumor size and the percentages of UICC-T4 determined before treatment were higher in PD-SAR. Total daily insulin dose was significantly higher in PD-SAR than in PD at 1 month, while showing no significant differences between the two groups thereafter. PD-SAR with preoperative CRT seems to be promising surgical strategy for PDAC of head and/or body with invasion of the splenic artery, in regard to the balance between operative radicality and postoperative QOL.
Validation of a Decision Rule and Derivation of a Modified Rule to Obtain Chest Radiograph in Patients with Nontraumatic Chest Pain in the Emergency Department
Authors: Newsom Case , Jeanmonod Rebecca , Weller Karl , Boutros Nabil , Reiter Mark , Jeanmonod Donald
Published: June 2014

Objectives. We sought to validate and refine a decision rule for chest X-ray (CXR) utilization in nontraumatic chest pain (CP) patients presenting to the emergency department (ED).Methods. Retrospective review of ED patients presenting with CP who had CXR performed during three nonconsecutive months was performed. The presence of 18 variables derived from history and exam was ascertained. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the original rule were calculated. Refinement using additional variables was performed.Results. 967 patient charts were reviewed. 89.9% of CXR were normal, 5.2% had insignificant findings, and 5.1% had significant findings. Application of the criteria had a sensitivity/specificity of 74%/59% and a PPV/ NPV of 9%/98%. Rule modification to obtain CXR for age ≥ 65 years, history of congestive heart failure and alcohol abuse, and exam findings of decreased breath sounds, fever, and tachypnea maintained sensitivity while improving specificity to 69%.Conclusions. Most CP patients have normal CXRs. Narrowing a decision rule to obtain CXR in patients with age ≥ 65 years, history of congestive heart failure and alcohol abuse, and exam findings of decreased breath sounds, fever, and tachypnea maintain sensitivity while improving specificity and NPV.
A Novel Filled Function Method for Nonlinear Equations
Authors: Yuan Liuyang , Tang Qiuhua
Published: June 2014

A novel filled function method is suggested for solving box-constrained systems of nonlinear equations. Firstly, the original problem is converted into an equivalent global optimization problem. Subsequently, a novel filled function with one parameter is proposed for solving the converted global optimization problem. Some properties of the filled function are studied and discussed. Finally, an algorithm based on the proposed novel filled function for solving systems of nonlinear equations is presented. The objective function value can be reduced by quarter in each iteration of our algorithm. The implementation of the algorithm on several test problems is reported with satisfactory numerical results.
Removal of Muscle Artifacts from Single-Channel EEG Based on Ensemble Empirical Mode Decomposition and Multiset Canonical Correlation Analysis
Authors: Chen Xun , He Chen , Peng Hu
Published: June 2014

Electroencephalogram (EEG) recordings are often contaminated with muscle artifacts. This disturbing muscular activity strongly affects the visual analysis of EEG and impairs the results of EEG signal processing such as brain connectivity analysis. If multichannel EEG recordings are available, then there exist a considerable range of methods which can remove or to some extent suppress the distorting effect of such artifacts. Yet to our knowledge, there is no existing means to remove muscle artifacts from single-channel EEG recordings. Moreover, considering the recently increasing need for biomedical signal processing in ambulatory situations, it is crucially important to develop single-channel techniques. In this work, we propose a simple, yet effective method to achieve the muscle artifact removal from single-channel EEG, by combining ensemble empirical mode decomposition (EEMD) with multiset canonical correlation analysis (MCCA). We demonstrate the performance of the proposed method through numerical simulations and application to real EEG recordings contaminated with muscle artifacts. The proposed method can successfully remove muscle artifacts without altering the recorded underlying EEG activity. It is a promising tool for real-world biomedical signal processing applications.
Cost-Effectiveness Analysis of a PVGS on the Electrical Power Supply of a Small Island
Authors: Hsu Cheng-Ting , Korimara Roman , Cheng Tsun-Jen
Published: June 2014

This paper presents a feasibility study of a large simulated stadium-scale photovoltaic generation system (PVGS) on a small island. Both the PVGS contribution to the energy demand on the island and its financial analysis were analysed in this study. The maximum allowable PVGS installation capacity is obtained by executing load flow analysis without violating the voltage magnitude and voltage variation ratio limits. However, the estimated power generation of PVGS is applied to know its impact on the power system according to the hourly solar irradiation and temperature. After that, the cost-benefit analysis of payback years (PBY) and net present value (NPV) method is derived considering the cash flow from utilities annual fuel and loss saving, the operation and maintenance (O&M) cost, and the capital investment cost. The power network in Kiribati (PUB DNST) is selected for study in this paper. The simulation results are very valuable and can be applied to the other small islands for reducing the usage of fossil fuel and greenhouse gas emissions.
A Semiempirical MIMO Channel Model in Obstructed Viaduct Scenarios on High-Speed Railway
Authors: Zhou Tao , Tao Cheng , Liu Liu , Tan Zhenhui
Published: June 2014

A semiempirical multiple-input multiple-output (MIMO) channel model is proposed for high-speed railway (HSR) viaduct scenarios. The proposed MIMO model is based on the combination of realistic single-input single-output (SISO) channel measurement results and a theoretical geometry-based stochastic model (GBSM). Temporal fading characteristics involvingK-factor and Doppler power spectral density (PSD) are derived from the wideband measurement under an obstructed viaduct on Zhengzhou-Xi’an HSR in China. The GBSM composed of a one-ring model and an elliptical model is employed to describe the entire propagation environment. Environment-related parameters in the GBSM are determined by the measured temporal fading properties. And a close agreement is achieved between the model results and measured data. Finally, a deterministic simulation model is established to perform the analysis of the space-time correlation function, the space-Doppler PSD, and the channel capacity for the measured scenario. This model is more realistic and particularly beneficial for the performance evaluation of MIMO systems in HSR environments.
Differential Effects of Naja naja atra Venom on Immune Activity
Authors: Kou Jian-Qun , Han Rong , Xu Yin-Li , Ding Xiao-Lan , Wang Shu-Zhi , Chen Cao-Xin , Ji Hong-Zhang , Ding Zhi-Hui , Qin Zheng-Hong
Published: June 2014

Previous studies reported that Naja naja atra venom (NNAV) inhibited inflammation and adjuvant arthritis. Here we investigated the role of NNAV in regulation of immune responses in mice. Oral administration of NNAV to normal mice showed significant increase in natural killer cell activity, B lymphocyte proliferation stimulated by lipopolysaccharides, and antibody production in response to sheep red blood cells. Meanwhile, NNAV markedly decreased T lymphocyte proliferation stimulated by concanavalin A, arrested the cell cycle at G0/G1 phase, and suppressed CD4 and CD8 T cell divisions. Furthermore, NNAV inhibited the dinitrofluorobenzene‐induced delayed‐type hypersensitivity reaction. This modulation of immune responses may be partly attributed to the selective increase in Th1 and Th2 cytokines (IFN‐γ, IL‐4) secretion and inhibition of Th17 cytokine (IL‐17) production. In dexamethasone‐induced immunosuppressed mice, NNAV restored the concentration of serum IgG and IgM, while decreasing the percentage of CD4 and CD8 T‐cell subsets. These results indicate that NNAV enhances the innate and humoral immune responses while inhibiting CD4 Th17 and CD8 T cell actions, suggesting that NNAV could be a potential therapeutic agent for autoimmune diseases.