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Simulation with Fluctuating and Singular Rates

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Communications in Computational Physics 2014年第7期16卷 287-306页

作者： Farzin Barekat russel Caflisch Mathematics Department University of California at Los AngelesLos AngelesCA 90095-1555USA.

In this paper we present a method to generate independent samples for a general random variable,either continuous or *** algorithm is an extension of the Acceptance-Rejectionmethod,and it is particularly useful for kinetic simulation in which the rates are fluctuating in time and have singular limits,as occurs for exam-ple in simulation of recombination interactions in a *** it depends on some additional requirements,the new method is easy to implement and rejects less samples than the Acceptance-Rejection method.

关键词： Sampling Monte Carlo Acceptance/Rejection method plasma recombination.

Temporal trends in organophosphorus pesticides use and concentrations in river water in Japan, and risk assessment

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Journal of Environmental Sciences 2019年第5期31卷 135-152页

作者： Aly Derbalah russel Chidya Waqar Jadoon Hiroshi Sakugawa Graduate School of Biosphere Science 1-7-1 Pesticides Chemistry and Toxicology Department Faculty of Agriculture Kafrelsheikh University Department of Water Resources Management and Development Faculty of Environmental Sciences Mzuzu University

We reviewed organophosphorus pesticide use in Japan between 1982 and 2016 using data from the National Institute of Environmental Studies. Organophosphorus pesticide concentrations in river water throughout Japan were taken from the literature, and risk assessments were performed for some organophosphorus pesticides based on risk quotients and hazard quotients. Assessments were performed for 20 common pesticides,including insecticides, fungicides, and herbicides. The amounts used decreased in the order: insecticides > herbicides > fungicides. Organophosphorus insecticide and fungicide use have decreased over the last four decades, but organophosphorus herbicide use has increased. During this period, annual organophosphorus pesticide use was the highest for chlorpyrifos(105,263 tons/year) and the lowest for glyphosate-sodium(8 tons/year). The ecotoxicological risk assessment indicated that diazinon and fenitrothion posed strong risks to the Japanese aquatic environment, and chlorpyrifos and malathion have moderate risks. None of the pesticides that were assessed posed significant risks to *** use of organophosphorus pesticides in Japan may cause strong risks to aquatic environments. These risks should be reassessed periodically.

关键词： Organophosphorus Pesticide residue Risk quotient Hazard quotient Japan Water

An Unusual Cause of Irritability in a Single Ventricle Patient after Bidirectional Glenn Shunt

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Congenital Heart Disease 2021年第4期16卷 393-396页

作者： Sarah Pradhan Eileen Broomall russel Hirsch The Heart Institute Cincinnati Children’s Hospital Medical CenterUniversity of Cincinnati College of MedicineCincinnatiOhioUSA Division of Neurology Cincinnati Children’s Hospital Medical CenterDepartment of PediatricsUniversity of Cincinnati College of MedicineCincinnatiOhioUSA

The differential diagnosis for irritability in children is *** patients with congenital heart disease,one must strongly consider cardiac etiologies such as low cardiac output or elevated central venous pressure(CVP).In patients with single-ventricle physiology,the second stage of palliation includes bidirectional Glenn,which involves anastomosis of the superior vena cava to the pulmonary artery resulting in volume offloading of the single systemic ***,early in the post-operative period,patients may experience a headache due to the acute increase in CVP,and symptoms improve over *** intracranial hypertension(IIH),also known as pseudotumor cerebri,is a rare neurologic disorder in children,characterized by raised intracranial pressure(ICP)in the absence of brain parenchymal lesions or cerebrospinal fluid(CSF)*** the pathogenesis of IIH is unknown,early recognition and treatment of IIH are important to prevent permanent vision *** are only rare reports of IIH in patients with Fontan *** our knowledge,we report the first case of IIH in a 2-year-old female after bidirectional Glenn.

关键词： Single ventricle bidirectional Glenn shunt idiopathic intracranial hypertension pseudotumor cerebri

Micro-Calorimetric Method for Studying the Toxic Effect of Organic Arsenic on Bacillus Thuringiensis of Wild and Engineering Strains

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Micro-Calorimetric Method for Studying the Toxic Effect of O...

作者： Mohammad russel 中国地质大学

学位级别：硕士

砷(As)是一种常见的环境污染物。众所周知,这种类金属有致癌性和致畸性。长期以来,有机砷化合物被应用于农业生产。由于有机砷杀虫剂和除草剂的使用,我们的土壤环境被严重污染。鉴于此,在这次研究中我们选择有机砷化合物来评价有机砷对... 详细信息

砷(As)是一种常见的环境污染物。众所周知,这种类金属有致癌性和致畸性。长期以来,有机砷化合物被应用于农业生产。由于有机砷杀虫剂和除草剂的使用,我们的土壤环境被严重污染。鉴于此,在这次研究中我们选择有机砷化合物来评价有机砷对野生的和工程的苏云金芽孢杆菌的毒性作用。砷(As)及其氧化物普遍存在于自然界中,它们同时显现出金属性质和非金属性质。三价和五价的形式是最常见的氧化状态。从生物学和毒理学的观点上看,砷化合物被分为三大类:无机砷化合物、有机砷化合物和砷化氢气体。最常见的三价无机砷化合物有三氧化二砷、亚砷酸钠和三氯化砷。五价无机砷化合物包括五氧化二砷、砷酸和砷酸盐,例如砷酸铅和砷酸钙。常见的有机砷化合物是对氨苯基胂酸、甲胂酸、臭胂酸(二甲胂酸)和三甲胺基砷。三氧化二砷只轻微溶解于水中,它在氢氧化钠和三氯化砷与浓盐酸里形成亚砷酸盐。亚砷酸钠和砷酸钠都极易溶于水。原子价状态在水溶液中可能会发生交换,这取决于pH值以及其他具有氧化还原能力的物质。新标准突出了对砷在健康方面影响的关注。有机砷化合物的广泛使用,像农业中的杀虫剂,已经成为环境中砷污染的一个重要来源。当我们意识到大量砷正直接蔓延到农田时,环境影响也变得重要了。这次研究的目的是,使用微量热方法,结合微生物学、生物传感器、光谱学、色谱学等方法,鉴定有机砷化合物的毒性和地微生物在无氧和有氧情况下的作用。此研究是把转基因微生物(基因工程菌)和自然的地微生物进行比较的。这篇论文工作分为以下三个部分: A.探讨在不同砷化合物存在下微量热技术监测地微生物活性的方法。 B.用微量热法比较了两种有机砷(V)化合物monomethyle arsonic acid(MMA)和dimethyl arsenic acid(DMA)存在下对野生苏云金芽孢杆菌的影响,同时用微生物学、生物传感器、光谱学、色谱学等方法进行验证。结果发现,在两种有机砷化合物存在下,野生苏云金芽孢杆菌对有机砷(V)化合物产生了极高的抗性。从这个工作中成功地证明了有机砷对地微生物的毒性,同时也证明了微量热方法在生态毒理学领域具有广阔的应用前景。 C.选取一些基因工程菌来继续我们先前的工作。本文中,我们选取了两种上述B部分中的苏云金芽孢杆菌株:苏云金芽孢杆菌株A和苏云金芽孢杆菌株C。应用微量热方法监测它们的活动,同时用一些新的分析方法,如分光光度法,生物传感器和色谱法来证实研究方法的准确性。为了评价微生物对抗有机砷(V)化合物的毒性,我们在利用其他生物方法测量不同有机砷(V)化合物的剂量对微生物的生长率和活动影响的同时,也测出了在没有砷(V)化合物存在时,溶解氧(DO毫克/升)的含量减少。最后,我们成功地获得了我们的预期目标,即金属离子对地微生物毒性的剂量——效应。

关键词：微量热仪有机砷化合物苏云金芽孢杆菌毒性浊度变化溶解氧

Secretion of melatonin and 6-sulfatoxymelatonin urinary excretion in functional dyspepsia

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World Journal of Gastroenterology 2011年第21期17卷 2646-2651页

作者： Cezary Chojnacki Tomasz Poplawski Grazyna Klupinska Janusz Blasiak Jan Chojnacki russel J Reiter Department of Gastroenterology Medical University of Lodz90-647 LodzPoland Department of Molecular Genetics University of Lodz90-131 LodzPoland Department of Cellular and Structural Biology University of Texas Health Science CenterSan AntonioTX 78229-3901United States

To evaluate blood concentration of melatonin and urinary excretion of its metabolite, 6-sulfatoxymelatonin （6-OHMS）, in functional dyspepsia （FD）. METHODS： Ninety individuals were enrolled in the study： 30 in each study group： patients with postprandial distress syndrome （PDS）, epigastric pain syndrome （EPS）, and controls. Blood samples were drawn at 02：00 and 09：00 h and 24-h urine collection was performed. Serum melatonin and urinary 6-OHMS concentrations were measured by enzyme-linked immunosorbent assay. RESULTS： Serum melatonin concentration at night and in the morning was significantly （P 〈 0.001） higher inPDS patients [at 02：00 h-93.3 pg/mL, quartile range （QR）： 79.8-116.2; at 09.00 h-14.3 pg/mL, QR： 7.06-19.0] than in EPS （57.2 pg/mL, QR： 42.6-73.1, 8.1 pg/mL, QR： 4.2-9.3） and control patients （57.7 pg/mL, QR： 51.2-62.5; 8.1 pg/mL, QR： 5.4-10.3）. A similar relationship was observed for urinary 6-OHMS excretion. Patients with severe PDS symptoms had a higher melatonin concentration than these with moderate syndromes, whereas patients with severe EPS had a lower urinary 6-OHMS excretion than patients with moderate ***： Evaluation of melatonin serum concentrations and 24-h urinary 6-OHMS excretion are useful methods for differential diagnosis of various clinical forms of FD.

关键词： Functional dyspepsia Postprandial distress syndrome Epigastric pain syndrome Melatonin 6-sulfatoxymelatonin

Melatonin,tunneling nanotubes,mesenchymal cells,and tissue regeneration

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Neural Regeneration Research 2023年第4期18卷 760-762页

作者： Francesca Luchetti Silvia Carloni Maria G.Nasoni russel J.Reiter Walter Balduini Department of Biomolecular Sciences University of Urbino Carlo BoUrbinoItaly Department of Cell Systems and Anatomy Long School of MedicineUT HealthSan AntonioTXUSA

Mesenchymal stem cells are multipotent stem cells that reside in many human tissues and *** stem cells are widely used in experimental and clinical regenerative medicine due to their capability to transdifferentiate into various ***,when transplanted,they lose part of their multipotency and immunomodulatory properties,and most of them die after injection into the damaged *** this review,we discuss the potential utility of melatonin in preserving mesenchymal stem cells’survival and function after *** is a pleiotropic molecule regulating critical cell functions including apoptosis,endoplasmic reticulum stress,and *** is also synthesized in the mitochondria where it reduces oxidative stress,the opening of the mitochondrial permeability transition pore and the downstream caspase activation,activates uncoupling proteins,and curtails the proinflammatory *** addition,recent findings showed that melatonin also promotes the formation of tunneling nanotubes and the transfer of mitochondria between cells through the connecting *** mitochondrial dysfunction is a primary cause of mesenchymal stem cells death and senescence and a critical issue for survival after transplantation,we propose that melatonin by favoring mitochondria functionality and their transfer through tunneling nanotubes from healthy to suffering cells could improve mesenchymal stem cellbased therapy in a large number of diseases for which basic and clinical trials are underway.

关键词： brain ischemia cell transplantation melatonin mesenchymal stem cell mitochondria mitochondrial transplantation regenerative therapy senescence tunneling nanotubes

Modeling the mechanical properties of ultra-thin polymer films

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High Power Laser Science and Engineering 2017年第4期5卷 26-32页

作者： Francisco Espinosa-Loza Michael Stadermann Chantel Aracne-Ruddle Rebecca Casey Philip Miller russel Whitesides Lawrence Livermore National Laboratory 7000 East AvenueL-471LivermoreCA 94550USA

A modeling method to extract the mechanical properties of ultra-thin films(10–100 nm thick) from experimental data generated by indentation of freestanding circular films using a spherical indenter is presented. The relationship between the mechanical properties of the film and experimental parameters including load, and deflection are discussed in the context of a constitutive material model, test variables, and analytical approaches. Elastic and plastic regimes are identified by comparison of finite element simulation and experimental data.

关键词： indentation optimization ultra-thin films

Evaluation of enterochromaffin cells and melatonin secretion exponents in ulcerative colitis

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World Journal of Gastroenterology 2013年第23期19卷 3602-3607页

作者： Cezary Chojnacki Maria Wisniewska-Jarosińska Grazyna Kulig Ireneusz Majsterek russel J Reiter Jan Chojnacki Department of Gastroenterology Medical University of Lodz90-647 Lodz Poland Department of Clinical Chemistry and Biochemistry Medical University of Lodz90-647 Lodz Poland Department of Cellular and Structural Biology University of Texas Health Science CenterSan Antonio TX 78229 United States

AIM: To study an assessment of the number of enterochromaffin cells and expression of hydroxyindole-Omethyltransferase in colonic mucosa and urine excretion of 6-sulfatoxymelatonin in patients with ulcerative colitis. METHODS: The study included 30 healthy subjects (groupⅠ-C), 30 patients with ulcerative proctitis [group Ⅱ-ulcerative proctitis (UP)] and 30 patients with ulcerative colitis [group Ⅲ-ulcerative colitis (UC)] in acute phases of these diseases. The number of enterochromaffin cells (EC) was estimated in rectal and colonic mucosa. Bioptates were assembled from many different parts of the large intestine. Immunorective cells collected from various parts of the colon were counted according to the Eurovision DAKO (Dako A/S, Copenhagen, Denmark) System in the range of 10 fields in each bioptate at × 200 magnification. The level of mRNA expression of hydroxyindole-O-methyltransferase (HIOMT) in colonic mucosa was estimated with RT-PCR. Urine 6-sulfatoxymelatonin (6-HMS) excretion was determined immunoenzymatically using an IBL (IBL International GmbH, Hamburg, Germany) kit (RE 54031). RESULTS: The number of EC cells in healthy subjects (C) was 132.40 ± 31.26. In patients of group Ⅱ (UP) and group Ⅲ (UC) the number of these cells was higher 225.40 ± 37.35 (P < 0.001) and 225.24 ± 40.50 (P < 0.001) respectively. Similar differences were related to HIOMT expression, which was 1.04 ± 0.36 in group C, 1.56 ± 0.56 (P < 0.01) in group UP and 2.00 ± 0.35 (P < 0.001) in group UC. Twenty-four hour 6-HMS urinary excretion was as follows: C 16.32 ± 4.95 μg/24 h, UP 26.30 ± 7.29 μg/24 h (P < 0.01), UC 42.30 ± 12.56 μg/24h (P < 0.001). A correlation between number of EC cells and 6-HMS excretion was noted in all groups: r = 0.766 in patients with UP, r = 0.703 with UC and r = 0.8551 in the control group; the correlation between the results is statistically significant. CONCLUSION: In the acute phases of both UP and UC, proliferation of EC cells and high expression of HIOMT a

关键词： Enterochromaffin cells 5-hydroxyindoleO-methyltransferase 6-sulfatoxymelatonin Ulcerative proctitis Ulcerative colitis

Management of postoperative spinal infections

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World Journal of Orthopedics 2012年第11期3卷 182-189页

作者： Vishal Hegde Dennis S Meredith Christopher K Kepler russel C Huang Department of Orthopedic Surgery Weill Cornell Medical CollegeNew YorkNY 10021United States Department of Orthopedic Surgery Spine and Scoliosis ServiceHospital for Special SurgeryWeill Cornell Medical CenterNew YorkNY 10021United States Department of Orthopedic Surgery Rothman InstituteThomas Jefferson UniversityPhiladelphiaPA 19107United States

Postoperative surgical site infection(SSI) is a common complication after posterior lumbar spine surgery. This review details an approach to the prevention,diagnosis and treatment of SSIs. Factors contributing to the development of a SSI can be split into three categories:(1) microbiological factors;(2) factors related to the patient and their spinal pathology; and(3) factors relating to the surgical procedure. SSI is most commonly caused by Staphylococcus aureus. The virulence of the organism causing the SSI can affect its presentation. SSI can be prevented by careful adherence to aseptic technique,prophylactic antibiotics,avoiding myonecrosis by frequently releasing retractors and preoperatively optimizing modifiable patient factors. Increasing pain is commonly the only symptom of a SSI and can lead to a delay in diagnosis. C-reactive protein and magnetic resonance imaging can help establish the diagnosis. Treatment requires acquiring intra-operative cultures to guide future antibiotic therapy and surgical debridement of all necrotic tissue. A SSI can usually be adequately treated without removing spinalinstrumentation. A multidisciplinary approach to SSIs is important. It is useful to involve an infectious disease specialist and use minimum serial bactericidal titers to enhance the effectiveness of antibiotic therapy. A plastic surgeon should also be involved in those cases of severe infection that require repeat debridement and delayed closure.

关键词： Surgical site infection Spine surgery Discitis Postoperative infection