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Assessing the reproductive health of men with occupational exposures

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Asian Journal of Andrology 2014年第1期16卷 23-30页

作者： steven M Schrader Katherine L Marlow Centers for Disease Control and Prevention National Institute for Occupational Safety and Health Division of Applied Research and Technology Cincinnati OH USA.

The earliest report linking environmental （occupational） exposure to adverse human male reproductive effects dates back to1775 when an English physician, Percival Pott, reported a high incidence of scrotal cancer in chimney sweeps. This observation led to safety regulations in the form of bathing requirements for these workers. The fact that male-mediated reproductive harm in humans may be a result of toxicant exposures did not become firmly established until relatively recently, when Lancranjan studied lead-exposed workers in Romania in 1975, and later in 1977, when Whorton examined the effects of dibromochloropropane （DBCP） on male workers in California. Since these discoveries, several additional human reproductive toxicants have been identified through the convergence of laboratory and observational findings. Many research gaps remain, as the pool of potential human exposures with undetermined effects on male reproduction is vast. This review provides an overview of methods used to study the effects of exposures on male reproduction and their reproductive health, with a primary emphasis on the implementation and interpretation of human studies. Emphasis will be on occupational exposures, although much of the information is also useful in assessing environmental studies, occupational exposures are usually much higher and better defined.

关键词： accessory glands endocrine epidemiology semen sexual function sperm testis toxicology

Pathophysiology and treatment of Barrett's esophagus

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World Journal of Gastroenterology 2010年第30期16卷 3762-3772页

作者： Daniel S Oh steven R DeMeester Department of Surgery The University of Southern CaliforniaKeck School of MedicineLos AngelesCA 90033United States

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the United States. About 10%-15% of patients with GERD develop Barrett’s esophagus, which can progress to adenocarcinoma, currently the most prevalent type of esophageal cancer. The esophagus is normally lined by squamous mucosa, therefore, it is clear that for adenocarcinoma to develop, there must be a sequence of events that result in transformation of the normal squamous mucosa into columnar epithelium. This sequence begins with gastroesophageal reflux, and with continued injury metaplastic columnar epithelium develops. This article reviews the pathophysiology of Barrett’s esophagus and implications for its treatment. The effect of medical and surgical therapy of Barrett’s esophagus is compared.

关键词： Gastroesophageal reflux disease Barrett’s esophagus Lower esophageal sphincter Esophageal motility Proton pump inhibitors Antireflux surgery

Quantum Yang-Baxter equation and constant R-matrix over Grassmann algebra

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第10期6卷 1065-1079页

作者： DUPLIJ steven KOTULSKA Olga SADOVNIKOV Alexander Department of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 UkraineDepartment of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 UkraineDepartment of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 Ukraine

Constant solutions to Yang-Baxter equation are investigated over Grassmann algebra for the case of 6-vertex R-matrix. The general classification of all possible solutions over Grassmann algebra and particular cases with 2,3,4 generators are studied. As distinct from the standard case, when R-matrix over number field can have a maximum 5 nonvanishing elements, we obtain over Grassmann algebra a set of new full 6-vertex solutions. The solutions leading to regular R-matrices which appear in weak Hopf algebras are considered.

关键词： Constant solution Grassmann algebra Regularity R-matrix

CFD modeling and laboratory studies of dust cleaning efficacy of an efficient four stage non-clogging impingement filter for flooded-bed dust scrubbers

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International Journal of Coal Science & Technology 2022年第2期9卷 211-219页

作者： Ashish Ranjan Kumar Neeraj Gupta steven Schafrik Department of Mining Engineering University of KentuckyLexingtonKYUSA Department of Mining and Nuclear Engineering Missouri University of Science and Technology1400 N.Bishop AveRollaMO 65401USA

Fibrous-type flters are used to capture dust particles in mining and other occupations where personnel are exposed for prolonged *** cleansing devices including fooded-bed dust scrubbers use these mesh-type multi-layered *** flters trap dust particles efciently on their surface and inside their ***,their continued operation leads to dust build-up and *** results in increased resistance of the flter and lowered airfow rate through the *** could potentially enhance the exposure of the miners.A non-clogging self-cleaning impingement screen type dust flter was designed by the authors for use in mining and industrial dust cleansing *** flter guides dirt-laden air through rapidly turning paths which forces it to shed heavier *** particles impact one of the impermeable solid metallic flter surfaces and are removed from the airstream.A full cone water spray installed upstream prevents any surface buildup of *** paper summaried the computer models generated to show the flter operations and laboratory experiments including optical particle counting to establish the cleaning efciency.

关键词： Dust flter Computational fuid dynamics modeling Iso-kinetic sampling Optical particle counting Flooded-bed dust scrubber

Physical characteristics of conditioned anaerobic digested sludge-A fractal, transient and dynamic rheological viewpoint

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Journal of Environmental Sciences 2011年第8期23卷 1266-1273页

作者： Yili Wang Emilie Dieude-Fauvel steven K Dentel College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China. Department of Civil and Environmental Engineering University of Delaware Newark Delaware 19711 USA Cemagref Les Palaquins 03150 Montoldre Paris France

The changes in the physical characteristics of unconditioned and conditioned anaerobic digested sludge （ADS） biosolids, such as capillary suction time （CST）, yield stress, average size and fractal dimensions, were investigated through a CST test, transient and dynamic rheological test and image analysis. The results showed that the optimum polymer dose range was observed when CST or its reciprocal value was employed as an indicator. There were good correlations between the yield stresses determined from both a controlled shear stress test and a strain amplitude sweep test. The yield stress and storage modulus （G＇） increased as the polymer dose increased in most cases. A frequency sweep test revealed that polymer conditioning could extend the frequency sweep ranges for their elastic behaviors over viscous behaviors as well as the gel-like structure in the linear viscoelastic range. These results implied that more deformation energy was stored in this rigid structure, and that elastic behavior became increasingly dominant with the addition of the polymer in most cases, In addition, both the average sizes and two-dimensional fractal dimensions for conditioned ADS biosolids presented a similar up-climax-down variation trend as the polymer doses increased, whereas the critical polymer doses at the highest average sizes or two-dimensional fractal dimensions, were different. Correlation analysis revealed that the conditioned ADS dewaterability was not correlated with the yield stresses, while the average sizes or the two-dimensional fractal dimensions for conditioned ADS biosolids could be taken as the indication parameters for ADS dewaterability.

关键词： anaerobic digested sludge conditioning dynamic oscillatory test yield stress fractal dimensions polymer dose

Discussion on Relevance and Studies of Prescription Compatibility in Chinese Medicine

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Chinese Journal of Integrative Medicine 2021年第10期27卷 788-793页

作者： Loh Cheng Toa steven Goh Xin Yi NTU Chinese Medicine Clinic Nanyang Technological UniversitySingapore(637551)

With Chinese medicine(CM)gaining popularity in recent years,researchers and clinicians have put in much interest and effort into the makings and effects of it,especially after the recent announcement of World Health Orgnitation's incorporation of CM into mainstream medical *** herb has complex properties,coming from its pharmacological properties and the Chinese medical principles of organ-directed,taste and dynamic orientational *** use of individual herb in CM is rare,where various herbs/ingredients are mostly found in a prescribed *** fully reveal the effects of CM is a great *** complexity of various herbs in combined effect,the absorption and utility rate by the body,uniqueness of individual physique,sub-types of pathological behaviors and time-line progression of the healing process add on to the complication of understanding the full effect of *** theories such as pathophysiology guidance,pharmacokinetic-pharmacodynamic compatibility method,and Global Systems Biology for Integrative Genomics,Proteomics and Metabolomics,which interactively provide a wider scope,more details,with the consideration of development time-line,may shed more light to revealing the full picture of the effects of compatibility prescription.

关键词： Chinese medicine integrative effects methodologies prescription compatibility

Deriving the magnetopause position from wide field-of-view soft X-ray imager simulation

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Science China Earth Sciences 2022年第8期65卷 1601-1611页

作者： Yihong GUO Tianran SUN Chi WANG steven SEMBAY Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China National Space Science Center Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK

Imaging techniques provide essential information in astronomical and space physics *** Soft X-ray Imager(SXI)will obtain images of the Earth’s magnetosphere via the solar wind charge exchange process in a global ***,it is a challenge to reconstruct its 3-D structures from the observed 2-D image(s).In this paper,a recently proposed method,Tangent Fitting Approach(TFA),is validated to reconstruct the large-scale magnetopause from a single X-ray image obtained by instrument *** is revealed that the large-scale magnetopause under a medium solar wind number density can be well reconstructed,although the locations of maximum X-ray photon counts are scattered in the image due to instrumental effects and diffusive sky *** solar wind number density leads to stronger signals and further leads to better reconstruction *** lower solar wind density,the X-ray maximum photon counts may not be identified from the SXI simulations,preprocessing of the images shall be considered before applying ***,the subsolar magnetopause can be well derived when the satellite is on the dayside orbits.

关键词： Soft X-ray Imager Magnetosphere SMILE TFA

H_∞ fault estimation for a class of linear time-delay systems in finite frequency domain

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Journal of Systems Engineering and Electronics 2010年第5期21卷 835-841页

作者： Quanchao Dong Maiying Zhong steven X. Ding School of Control Science and Engineering Shandong University Jinan 250061 E R. China School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100191 P. R. China Institute for Automatic Control and Complex Systems University of Duisburg-Essen Duisburg 47057 Germany

This paper deals with the problem of H∞ fault estimation for linear time-delay systems in finite frequency *** a generalized coordinate change is applied to the original system such that in the new coordinates all the time-delay terms are injected by the system＇s input and *** an observer-based H∞ fault estimator with input and output injections is proposed for fault estimation with known frequency *** the aid of Generalized Kalman-Yakubovich-Popov lemma,sufficient conditions on the existence of the H∞ fault estimator are derived and a solution to the observer gain matrices is obtained by solving a set of linear matrix ***,a numerical example is given to illustrate the effectiveness of the proposed method.

关键词： fault estimation time-delay generalized coordinate change generalized Kalman-Yakubovich-Popov lemma finite frequency domain.

Compressive deformation of ultralong amyloid fibrils

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Acta Mechanica Sinica 2010年第6期26卷 977-986页

作者： Raffaella Paparcone steven Cranford Markus J.Buehler Laboratory for Atomistic and Molecular Mechanics

Involved in various neurodegenerative diseases, amyloid fibrils and plaques feature a hierarchical structure, ranging from the atomistic to the micrometer *** the atomistic level,a dense and organized hydrogen bond network is resembled in a beta-sheet rich secondary structure, which drives a remarkable stiffness in the range of 10-20GPa,larger than many other biological nanofibrils, a result confirmed by both experiment and ***, the understanding of how these exceptional mechanical properties transfer from the atomistic to the nanoscale remains *** we report a multiscale analysis that, from the atomistic-level structure of a single fibril,extends to the mesoscale level,reaching size scales of hundreds of *** use parameters directly derived from full atomistic simulations of Aβ（1-40） amyloid fibrils to parameterize a mesoscopic coarse-grained model,which is used to reproduce the elastic properties of amyloid *** then apply our mesoscopic model in an analysis of the buckling behavior of amyloid fibrils with different lengths and report a comparison with predictions from continuum beam theory. An important implication of our results is a severe reduction of the effective modulus due to buckling,an effect that could be important to interpret experimental results of ultralong amyloid *** model represents a powerful tool to mechanically characterize molecular structures on the order of hundreds of nanometers to micrometers on the basis of the underlying atomistic *** work provides insight into structural and mechanical properties of amyloid fibrils and may enable further analysis of larger-scale assemblies such as amyloidogenic bundles or plaques as found in disease states.

关键词： Amyloid Coarse-grain Molecular simulation Nanomechanics Materiomics