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Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields

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Plasma Science and Technology 2019年第9期21卷 1-18页

作者： Hirotake SUGAWARA division of Electronics for informatics Graduate School of Information Science and TechnologyHokkaido University

This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well.

关键词： propagator method electron velocity distribution function electron transport coefficients crossed electric and magnetic fields magnetized plasma Boltzmann equation

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Measure oriented training： a targeted approach to imbalanced classification problems

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Frontiers of Computer Science 2012年第5期6卷 489-497页

作者： Bo YUAN Wenhuang LIU division of informatics Graduate School at ShenzhenTsinghua UniversityShenzhen 518055China

Since the overall prediction error of a classifier on imbalanced problems can be potentially misleading and bi- ased, alternative performance measures such as G-mean and F-measure have been widely adopted. Various techniques in- cluding sampling and cost sensitive learning are often em- ployed to improve the performance of classifiers in such sit- uations. However, the training process of classifiers is still largely driven by traditional error based objective functions. As a result, there is clearly a gap between the measure accord- ing to which the classifier is evaluated and how the classifier is trained. This paper investigates the prospect of explicitly using the appropriate measure itself to search the hypothesis space to bridge this gap. In the case studies, a standard three- layer neural network is used as the classifier, which is evolved by genetic algorithms （GAs） with G-mean as the objective function. Experimental results on eight benchmark problems show that the proposed method can achieve consistently fa- vorable outcomes in comparison with a commonly used sam- pling technique. The effectiveness of multi-objective opti- mization in handling imbalanced problems is also demon- strated.

关键词： imbalanced datasets genetic algorithms (GAs),neural networks G-mean synthetic minority over-sampling technique (SMOTE)

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Transcriptional activators and activation mechanisms

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Protein & Cell 2011年第11期2卷 879-888页

作者： Jun Ma division of Biomedical informatics Division of Developmental BiologyCincinnati Children's Research FoundationUniversity of Cincinnati College of MedicineCincinnatiOH 45229USA

Transcriptional activators are required to turn on the expression of genes in a eukaryotic *** bound to the enhancer can facilitate either the recruitment of RNA polymerase II to the promoter or its *** article examin... 详细信息

关键词： activator transcription co-activator enhancer promoter signal transduction development

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Modulation of B-cell receptor and microenvironment signaling by a guanine exchange factor in B-cell malignancies

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Cancer Biology & Medicine 2016年第2期13卷 277-285页

作者： Wei Liao Sanjai Sharma division of Hematology-Oncology Greater Los Angeles VA Healthcare Center UCLA School of Medicine

Objective： Chronic lymphocytic leukemia （CLL） and mantle cell lymphoma （MCL） cells over-express a guanine exchange factor （GEF）, Rasgrf-1. This GEF increases active Ras as it catalyzes the removal of GDP from Ras so that GTP can bind and activate Ras. This study aims to study the mechanism of action of Rasgrf-1 in B-cell malignancies. Methods： N-terminus truncated Rasgrf-1 variants have a higher GEF activity as compared to the full-length transcript therefore a MCL cell line with stable over-expression of truncated Rasgrf-1 was established. The B-cell receptor （BCR） and chemokine signaling pathways were compared in the Rasgrf-I over-expressing and a control transfected cell line. Results： Cells over-expressing truncated form of Rasgrf-1 have a higher proliferative rate as compared to control transfected cells. BCR was activated by lower concentrations of anti-IgM antibody in Rasgrf-1 over-expressing cells as compared to control cells indicating that these cells are more sensitive to BCR signaling. BCR signaling also phosphorylates Rasgrf-1 that further increases its GEF function and amplifies BCR signaling. This activation of Rasgrf-1 in over-expressing cells resulted in a higher expression of phospho-ERK, AKT, BTK and PKC-alpha as compared to control cells. Besides BCR, Rasgrf-1 over-expressing cells were also more sensitive to microenvironment stimuli as determined by resistance to apoptosis, chemotaxis and ERK pathway activation. Conclusions： This GEF protein sensitizes B-cells to BCR and chemokine mediated signaling and also upregulates a number of other signaling pathways which promotes growth and survival of these cells.

关键词： B-ceU malignancies mantle cell lymphoma chronic lymphocytic leukemia (CLL) B-cell receptor guanine exchange factorRasgrf- 1 ERK pathway

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A dwarf bamboo(Pleioblastus chino) and winter browsing by Japanese hare(Lepus brachyurus) combine to limit establishment of transplanted native tree seedlings in an abandoned agricultural field

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Journal of Forestry Research 2016年第6期27卷 1287-1294页

作者： Yoshinori Tokuoka Kentaro Ohigashi Koji Watanabe Hiroshi Yamaguchi Takahiro Ara Nobukazu Nakagoshi Biodiversity division National Institute for Agro-Environmental Sciences (NIAES) Ecosystem informatics division NIAES Experimental Farm Management division NIAES Graduate School for International Development and Cooperation Hiroshima University

Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplanted native tree species （Quercus myrsinifolia, Quercus serrata, Aphananthe aspera, and Rhus sylvestris） by experimentally manipulating the vegetation cover, which was mainly dominated by dwarf bamboo （Pleioblastus chino）, and herbivore access to the planting sites on farmland that had been abandoned for 15 years at the start of the study. Few transplanted seedlings of any species survived under intact vegetation cover, irrespective of herbivore presence. In gaps in the vegetation cover, winter browsing by Japanese hare （Lepus brachyurus） damaged all species. However, lower browsing frequency and higher resprouting ability after grazing of the seedlings enabled both Quercus species to survive better than the other species. These results indicate that dwarf bamboo and the hare jointly limit the establishment of native trees in old fields. If active afforestation by transplanting seedlings at sites dominated by dwarf bamboo is planned, a combination of vegetation removal, selection of suitable species, and temporary seedling protection will be most effective.

关键词： Farmland abandonment Microsite limitation Monodominant dwarf bamboo Resprouting Seedling herbivory

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Evaluating a combined bowel preparation for small-bowel capsule endoscopy:a prospective randomized–controlled study

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Gastroenterology Report 2020年第1期8卷 31-35,I0001,I0002页

作者： Stephanie L.Hansel Joseph A.Murray Jeffrey A.Alexander David H.Bruining Mark V.Larson Thomas F.Mangan Ross A.Dierkhising Ann E.Almazar Elizabeth Rajan division of Gastroenterology and Hepatology Mayo ClinicRochesterMNUSA division of Biomedical Statistics and informatics Mayo ClinicRochesterMNUSA

Background:Capsule endoscopy(CE)is frequently hindered by intra-luminal *** aim was to determine whether a combination bowel preparation would improve small-bowel visualization,diagnostic yield,and the completion rate of ***:Single-blind,prospective randomized–controlled study of outpatients scheduled for ***-preparation subjects ingested 2 L of polyethylene glycol solution the night prior to CE,5mL simethicone and 5mg metoclopramide 20 minutes prior to CE and laid in the right lateral position 30 minutes after swallowing *** had no solid food after 7 *** night prior to CE and no liquids 4 hours prior to *** completed a satisfaction *** readers completed a small-bowel-visualization ***:Fifty patients were prospectively enrolled(56%female)with a median age of 54.4 years and 44 completed the study(23 patients in the control group and 21 in the preparation group).There was no significant difference between groups on quartile-based small-bowel visualization(all P>0.05).There was no significant difference between groups in diagnostic yield(P=0.69),mean gastric(P=0.10)or small-bowel transit time(P=0.89).The small-bowel completion rate was significantly higher in the preparation group(100%vs 78%;P=0.02).Bowel-preparation subjects reported significantly more discomfort than controls(62%vs 17%;P=0.01).Conclusions:Combined bowel preparation did not improve small-bowel visualization but did significantly increase patient *** CE completion rate improved in the preparation group but the diagnostic yield was *** on our findings,a bowel preparation prior to CE does not appear to improve CE performance and results in decreased patient satisfaction(***,***01243736).

关键词： bowel preparation capsule endoscopy small-bowel visualization patient satisfaction

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Ab initio Study of Tunable Band Gap of Monolayer and Bilayer Phosphorene by the Vertical Electronic Field

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Journal of Wuhan University of Technology(Materials Science) 2017年第1期32卷 213-216页

作者：汪涛 GUO Wei WEN Luowei LIU Yan 张斌 SHENG Kuang 尹友 College of Electrical Engineering Department of Radiology Second Affiliated Hospital Zhejiang University division of Electronics and informatics Gunma University

Using the ab initio plane-wave ultrasoft pseudopotential method based on generalized gradient approximation（GGA）,we investigated the band-gap tuning in monolayer phosphorene（MLP） and bilayer phosphorene（BLP） by external electric fields applied perpendicular to the *** band continuously decreases with increasing applied electric fields,eventually rendering them *** MLP,the phenomenon is explained in the light of the giant Stark effect,which is essentially characterized by the interlayer spacing,for the rate of change of bandgap with applied external *** atomic distance and charges also contribute to the semiconductor-metal *** BLP is more sensitive to electric fields than MLP,since their charges are rearranged among bilayers and the bandgap can dramatically drop in terms of electronic *** results show the bandgap will change for the fabrication of novel electronic and photonic devices.

关键词： phosphorene bandgap electric field

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Towards reperfusion-centric preclinical stroke research:outside the box of “reperfusion injury”

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Neural Regeneration Research 2015年第4期10卷 534-536页

作者： Chia Yi Kuan Yu Yo Sun Department of Pediatrics Children’s Healthcare of AtlantaDivision of Neurologyand the Center for Neurodegenerative Diseases (CND)The Emory University School of Medicine Department of Pediatrics Children’s Healthcare of AtlantaDivision of NeurologyThe Emory University School of Medicine

Stroke is a major health issue of increasing significance for any society with an aging population. Globally, stroke is the second-leading cause of death with approximately 5.9 million fatal events in 2010, equivalent to 11.1% of all deaths. Yet, despite years of preclinical research on neuroprotection and a multitude of clinical trials, tissue plas- minogen activator （tPA）-mediated recanalization remains the mainstay of acute ischemic stroke therapy, whereas tPA thrombolysis rarely provides benefits in the mechanical occlusion-based stroke models. This split between the bench and bedside raised the concern over the clinical ap- plicability of neuroprotection in acute ischemic stroke. In this perspective commentary, we call for attention to the differences between mechanical-occlusion and thrombo- embolic stroke models in cerebral hemodynamics （Figure 1A, B）, the implications of these differences in view of progressive pathobiology of ischemic stroke （Figure 1C）, and the need and strategies towards reperfusion-centric preclinical stroke research.

关键词： Towards reperfusion-centric preclinical stroke research PA reperfusion injury MCAO

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Effects of transdermal magnesium chloride on quality of life for patients with fibromyalgia: a feasibility study

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Journal of Integrative Medicine 2015年第5期13卷 306-313页

作者： Deborah J.Engen Samantha J.Mc Allister Mary O.Whipple Stephen S.Cha Liza J.Dion Ann Vincent Brent A.Bauer Dietlind L.Wahner-Roedler Department of Physical Medicine and Rehabilitation Mayo Clinic division of General Internal Medicine Mayo Clinic division of Biomedical Statistics and informatics Mayo Clinic

BACKGROUND： Fibromyalgia is a syndrome characterized by chronic pain, fatigue, depression, and sleep disturbances. Its primary cause is unclear. Several studies have reported decreased intracellular magnesium levels in patients with fibromyalgia and have found negative correlation between magnesium levels and fibromyalgia symptoms.OBJECTIVE： To gather preliminary data on whether transdermal magnesium can improve quality of life for women who have fibromyalgia. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS： This is a patient questionnaires and survey in a fibremyalgia clinic at a tertiary medical center. Forty female patients with the diagnosis of fibremyalgia were enrolled. Each participant was provided a spray bottle containing a transdermal magnesium chloride solution and asked to apply 4 sprays per limb twice daily for 4 weeks. Participants were asked to complete the Revised Fibromyalgia Impact Questionnaire, SF-36v2 Health Survey, and a quality-of-life analog scale at baseline, week 2, and week 4. MAIN OUTCOME MEASURE： Questionnaire and survey scores, evaluated through intent-to-treat and per-protocol analyses. RESULTS： Twenty-four patients completed the study （mean [SD] age, 57.2 [7.6] years; white, 95%; mean body mass index, 31.3 kg/m2）. With intention-to-treat analysis, Revised Fibromyalgia Impact Questionnaire subscale and total scores were significantly improved at week 2 and week 4 （total score, P = 0.001）. Per-protocol analysis results were similar： all subscales of the Revised Fibremyalgia Impact Questionnaire were significantly improved at week 2 and week 4 （total score, P = 0.001）. CONCLUSION： This pilot study suggests that transdermal magnesium chloride applied on upper and lower limbs may be beneficial to patients with fibromyalgia.

关键词： fibromyalgia magnesium chloride Revised Fibromyalgia Impact Questionnaire clinical trial

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Inflammasome links traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1644-1664页

作者： Gabriela Seplovich Yazan Bouchi Juan Pablo de Rivero Vaccari Jennifer C.Munoz Pareja Andrew Reisner Laura Blackwell Yehia Mechref Kevin K.Wang J.Adrian Tyndall Binu Tharakan Firas Kobeissy Department of Surgery Morehouse School of MedicineAtlantaGAUSA Department of Neurobiology Center for NeurotraumaMultiomics&Biomarkers(CNMB)Neuroscience InstituteMorehouse School of MedicineAtlantaGAUSA Department of Neurological Surgery and the Miami Project to Cure Paralysis University of Miami Miller School of MedicineMiamiFLUSA division of Pediatric Critical Care Department of PediatricsUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Pediatrics Emory UniversityAtlantaGAUSA Department of Neurosurgery Children’s Healthcare of AtlantaAtlantaGAUSA Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTXUSA Morehouse School of Medicine AtlantaGAUSA

Traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease are three distinct neurological disorders that share common pathophysiological mechanisms involving neuroinflammation. One sequela of neuroinflammation includes the pathologic hyperphosphorylation of tau protein, an endogenous microtubule-associated protein that protects the integrity of neuronal cytoskeletons. Tau hyperphosphorylation results in protein misfolding and subsequent accumulation of tau tangles forming neurotoxic aggregates. These misfolded proteins are characteristic of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease and can lead to downstream neuroinflammatory processes, including assembly and activation of the inflammasome complex. Inflammasomes refer to a family of multimeric protein units that, upon activation, release a cascade of signaling molecules resulting in caspase-induced cell death and inflammation mediated by the release of interleukin-1β cytokine. One specific inflammasome, the NOD-like receptor protein 3, has been proposed to be a key regulator of tau phosphorylation where it has been shown that prolonged NOD-like receptor protein 3 activation acts as a causal factor in pathological tau accumulation and spreading. This review begins by describing the epidemiology and pathophysiology of traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease. Next, we highlight neuroinflammation as an overriding theme and discuss the role of the NOD-like receptor protein 3 inflammasome in the formation of tau deposits and how such tauopathic entities spread throughout the brain. We then propose a novel framework linking traumatic brain injury, chronic traumatic encephalopathy, and Alzheimer's disease as inflammasomedependent pathologies that exist along a temporal continuum. Finally, we discuss potential therapeutic targets that may intercept this pathway and ultimately minimize long-term neurological decline.

关键词： Alzheimer's disease caspase-1 chronic traumatic encephalopathy inflammasomes neurodegeneration neuroinflammation NLRP1 NLRP3 pyroptosis tauopathy traumatic brain injury

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