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Extent of morbidity associated with schistosomiasis infection in Malawi: a review paper

Infectious Diseases of Poverty 2015年第1期4卷 185-192页

作者： Austin H N Mtethiwa Gamba Nkwengulila Jared Bakuza Daniel Sikawa Abigail Kazembe Lilongwe University of Agriculture and Natural Resources(LUANAR) Bunda CampusPO Box 219LilongweMalawi Zoology Department University of Dar es SalaamCollege of Natural and Applied SciencePO Box 35064Dar es SalaamTanzania Biological Sciences Unit Dar es Salaam University College of Education(DUCE)PO Box 2329Dar es SalaamTanzania University of Malawi Kamuzu College of NursingPrivate Bag 1LilongweMalawi

Data on the extent of the burden due to schistosomiasis is sparse in most Sub-Saharan African countries.However,this data is crucial for triggering medical attention.A review of extent of morbidity and determinants associated with schistosomiasis in Malawi was therefore conducted to quantify the infection in order to concretise the need for medical intervention.A systematic and traditional search strategy was used to find literature for the review,whilst exclusion and inclusion criteria were used to identify appropriate articles.Logistic regression curves of epidemiological model Y=(a+bxc)/(1+bxc)and the recommendation that schistosomiasis prevalence can be used to estimate morbidity were employed to quantify morbidity at various infection stages.Morbidity was quantified as a direct proportion of the population and the respective national schistosomiasis prevalence.Findings showed that both S.mansoni and S.haematobium are present in Malawi with the latter highly prevalent(50%).Furthermore,out of the estimated population of 16,829 million,approximately 8.4 million have schistosomiasis,with about 4.4 million of these aged 18 years and below.The most frequent manifestation is Katayama syndrome,while ascites is the lowest,impacting about 3.0 million and 960 individuals,respectively.Localised studies on association of schistosomiasis infection to risk factors such as occupation,age and gender found odds ratio(OR)ranging from 1.29 to 5.37.Morbidity due to schistosomiasis is high in Malawi.It is therefore recommended that a more detailed study on the determinants of high schistosomiasis and re-evaluation of the current control measures be conducted if the current morbidity statistics are to be remarkably reduced.

关键词： Schistosomiasis Morbidity Risk factors quantification Burden Extent

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The Marking Technology in Motion Capture for the Complex Locomotor Behavior of Flexible Small Animals(Gekko gecko)

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Asian Herpetological Research 2019年第3期10卷 197-210页

作者： Zhouyi WANG Weijia ZONG Bingcheng WANG Junjie ZHU Kai QIN Zhendong DAI Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing 210016JiangsuChina Shanghai Institute of Aerospace System Engineering 3888 Yuanjiang RoadShanghai 201109China

Animals have evolved a variety of behavior patterns to adapt to the environment. Motion-capture technology is utilized to quantify and characterize locomotor behaviors to reveal the mechanisms of animal motion. In the capture of flexible, small animals with complex locomotor behaviors, the markers interfere with each other easily, and the motion forms(bending, twisting) of the moving parts are obviously different;thus, it is a great challenge to realize accurate quantitative characterization of complex locomotor behaviors. The correlation between the marker properties, including the size and space length, and the precision of the system are revealed in this paper, and the effects of diverse marker shapes on the capturing accuracy of the captured objects in different motion forms were tested. Results showed that the precision of system is significantly improved when the ratio of the space length to the diameter of the markers is larger than four;for the capture of the spatial twisting motion of the flexible object, the hexagon markers had the lowest spatial lost-marker rate relative to the circle, triangle, and square. Customized markers were used to capture the locomotor behavior of the gecko-inspired robot(rigid connection) and the gecko(flexible connection). The results showed that this marking technology can achieve high accuracy of motion capture for geckos(the average deviation was approximately 0.32 mm, and the average deviation’s variation rate was approximately 0.96%). In this paper, the marking technology for the motion capture of flexible, small animals with complex motion is proposed;it can effectively improve the system precision as well as the capture accuracy, and realize the quantitative characterization of the complex motion of flexible, small objects. It provides a reliable technical means to deeply study the evolution of the motion function of small animals and advance systematic research of motion-capture technology.

关键词： small flexible animals marking technology motion capture quantification of locomotor behavior gecko

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Quantitative Evaluation of Fatigue Crack Size Using Eddy Current Pulsed Thermography

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第3期34卷 247-254页

作者： Feng Fuzhou Xu Chao Zhu Junzhen Min Qingxu Sun Jiwei Key Laboratory of Nondestructive Testing of Ministry of Education Nanchang Aeronautical University Department of Mechanical Engineering Academy of Armored Force Engineering School of Electrical and Electronic Engineering Newcastle University

A set of metallic specimens containing fatigue cracks with different sizes were tested using eddy current pulsed thermography(ECPT),therefore the relations between heating response of the crack area and the crack length was studied.The numerical and experimental results both showed that the increase of the crack length enhanced the crack heating response under specific test conditions.A particular form of calculated response signal,which is linearly related to the crack length,was introduced to provide a quantitative evaluation of crack length.

关键词： ECPT fatigue crack heating response quantification

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A Study of Hyperbolicity of Kinetic Stochastic Galerkin System for the Isentropic Euler Equations with Uncertainty

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Chinese Annals of Mathematics,Series B 2019年第5期40卷 765-780页

作者： Shi JIN Ruiwen SHU School of Mathematical Sciences Institute of Natural SciencesMOE-LSEC and SHL-MACShanghai Jiao Tong University800 Dongchuan Rd.Shanghai 200240China Department of Mathematics University of MarylandCollege Park4176 Campus Dr.College ParkMD 20742USA.

The authors study the fluid dynamic behavior of the stochastic Galerkin(SG for short) approximation to the kinetic Fokker-Planck equation with random uncertainty.While the SG system at the kinetic level is hyperbolic, its fluid dynamic limit, as the Knudsen number goes to zero and the underlying kinetic equation approaches to the uncertain isentropic Euler equations, is not necessarily hyperbolic, as will be shown in the case study fashion for various orders of the SG approximations.

关键词： Hyperbolic equations Uncertainty quantification Stochastic Galerkin methods

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Solution of Liouville’s Equation for Uncertainty Characterization of the Main Problem in Satellite Theory

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Computer Modeling in Engineering & Sciences 2016年第3期111卷 269-304页

作者： Ryan Weisman Manoranjan Majji Kyle T.Alfriend Research Aerospace Engineer Air Force Research LaboratoryAFRL/RVSV 3550 Aberdeen Ave.SEKirtland AFB87117 Assistant Professor Mechanical and Aerospace Engineering DepartmentUniversity at Buffalo318 Jarvis HallBuffaloNY14260 TEES Research Professor Aerospace Engineering DepartmentTexas A&M UniversityCollege StationTX77843-3141

This paper presents a closed form solution to Liouville’s equation governing the evolution of the probability density function associated with the motion of a body in a central force field and subject to J2.It is shown that the application of transformation of variables formula for mapping uncertainties is equivalent to the method of characteristics for computing the time evolution of the probability density function that forms the solution of the Liouville’s partial differential equation.The insights derived from the nature of the solution to Liouville’s equation are used to reduce the dimensionality of uncertainties in orbital element space.It is demonstrated that the uncertainty propagation is fastest in the semi-major axis and the mean anomaly phase sub-space.The results obtained for uncertainty propagation for the two body problem are applied to investigate the uncertainty propagation in the presence of the J2 perturbation using a combination of osculating and mean element perturbation theory.Analytical orbital uncertainty propagation calculations are validated using Monte-Carlo results for several representative orbits.

关键词： Astrodynamics Uncertainty quantification

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Probabilistic Performance-Based Optimum Seismic Design Framework: Illustration and Validation

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 517-543页

作者： Yong Li Joel P.Conte Philip E.Gill Department of Civil and Environmental Engineering University of AlbertaEdmontonAB T6G 1H9Canada Department of Structural Engineering University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA Department of Mathematics University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA

In the field of earthquake engineering,the advent of the performance-based design philosophy,together with the highly uncertain nature of earthquake ground excitations to structures,has brought probabilistic performance-based design to the forefront of seismic design.In order to design structures that explicitly satisfy probabilistic performance criteria,a probabilistic performance-based optimum seismic design(PPBOSD)framework is proposed in this paper by extending the state-of-the-art performance-based earthquake engineering(PBEE)methodology.PBEE is traditionally used for risk evaluation of existing or newly designed structural systems,thus referred to herein as forward PBEE analysis.In contrast,its use for design purposes is limited because design is essentially a more challenging inverse problem.To address this challenge,a decision-making layer is wrapped around the forward PBEE analysis procedure for computer-aided optimum structural design/retrofit accounting for various sources of uncertainty.In this paper,the framework is illustrated and validated using a proof-of-concept problem,namely tuning a simplified nonlinear inelastic single-degreeof-freedom(SDOF)model of a bridge to achieve a target probabilistic loss hazard curve.For this purpose,first the forward PBEE analysis is presented in conjunction with the multilayer Monte Carlo simulation method to estimate the total loss hazard curve efficiently,followed by a sensitivity study to investigate the effects of system(design)parameters on the probabilistic seismic performance of the bridge.The proposed PPBOSD framework is validated by successfully tuning the system parameters of the structure rated for a target probabilistic seismic loss hazard curve.The PPBOSD framework provides a tool that is essential to develop,calibrate and validate simplified probabilistic performance-based design procedures.

关键词： Performance-based seismic design optimum seismic design forward PBEE analysis inverse PBEE analysis uncertainty quantification hazard deaggregation

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Development and implementation of incident response near-infrared models for analyzing contaminated medicines containing diethylene glycol solvent

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Journal of Innovative Optical Health Sciences 2014年第6期7卷 97-104页

作者： Lihui Yin Xuebo Zhang Xiaodong Li Shaohong Jin National Institutes for Food and Drug Control No.2 Tiantan Xili BeijingP.R.China

Samples of preparations contaminated by diethylene glycol(DEG),diethylene glycol raw materials and laboratory prepared solutions were measured to get NIR spectra.Then the iden-tification models were developed using the collected spectra and the spectra of distilled water,propylene glyool and the preparations without diethylene glyool.Besides,the quantification model was also established for determining the concentration of diethylene glyool in the pre-parations.V alidation results show the identification and quantification models have ideal pre-diction performance.The emergency NIR models are rapid,easy to use and accurate,and can be implemented for identifying diethylene glycol raw material,screening the preparations contam-inated by diethylene glycol in the markets and analyzing the concentrations of DEG.

关键词： Diethylene glycol near-infrared transmittance reflectance spectroscopy identification quantification

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Last but not the least: effects of laying sequence on egg color variation and embryonic development of Russet Sparrow(Passer cinnamomeus)

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Avian Research 2018年第3期9卷 198-205页

作者： Juan Huo Tongping Su Nan Niu Canchao Yang Wei Liang Ministry of Education Key Laboratory for Ecology of Tropical Islands College of Life Sciences Hainan Normal University College of Forestry Guangxi University

Background: Laying sequence has important effects on eggshell color and embryonic development in birds. Some birds can allocate resources unevenly among the eggs within a clutch, prioritizing those at the beginning of the laying sequence, in order to maximize reproductive success. The changes in egg color according to laying sequence may be an adaptation to pressure from predators or brood parasites.Methods: In this study, effects of laying sequence on egg color and embryonic heart rate in Russet Sparrows(Passer cinnamomeus) were investigated using artificial nest boxes. The eggs were divided into three groups: first to be laid, intermediate in the laying sequence, and last to be laid. We maintained the eggs in an incubator and measured embryonic heart rates.Results: Avian visual modeling showed that the background color brightness of the last eggs laid was significantly higher(whiter) than those of the other eggs. All eggs were about the same size and hatched around 13 days, indicating that laying sequence significantly affected embryonic development speed; the last eggs to be laid developed significantly faster than did the first in the clutch.Conclusions: Our study quantified the effect of laying sequence on egg color variation and proved that laying sequence has an important effect on embryonic heart rate in Russet Sparrows.

关键词： Egg color variation Egg color quantification Embryonic development Fiber optic spectrometer Laying sequence Russet Sparrow

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Multidirectional Gaussian Mixture Models for Nonlinear Uncertainty Propagation

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Computer Modeling in Engineering & Sciences 2016年第1期111卷 83-117页

作者： V.Vittaldev R.P.Russell Ph.D.Candidate The University of Texas at AustinAustinTXUSA. Associate Professor The University of Texas at AustinAustinTXUSA.

Monte Carlo simulations are an accurate but computationally expensive procedure for approximating the resultant non-Gaussian probability density function(PDF)after propagation of an initial Gaussian PDF through a nonlinear function.Univariate splitting libraries for Gaussian Mixture Models(GMMs)exist with up to five elements in the literature.The number of splits are extended in the present work by generating three homoscedastic univariate splitting libraries with up to 39 elements.Mulitvariate GMMs are typically handled with splits along a single direction.Instead,we generate a regular multidirectional grid over the initial multivariate Gaussian distribution by recursively applying the splitting library along multiple directions.The splitting direction is arbitrary and no longer limited to directions parallel to the columns of the square-root of the covariance matrix.A second order Stirling’s interpolation of the nonlinear function evaluated at the mean of the initial Gaussian distribution is used to quantify nonlinearity along candidate splitting directions.The directions with the highest nonlinearity benefit most from splitting.The Multidirectional GMM(MGMM)has applications for uncertainty quantification with computationally intensive nonlinear functions.The variable number of splits in each direction allows for a spectrum of models in the accuracy versus compute time design space,filling the gap between expensive Monte Carlos and fast linearized models.The multidirectional method is demonstrated with four test cases,including an orbit uncertainty propagation case,to illustrate the benefit of splitting along multiple directions and of ranking the splitting directions.

关键词： Uncertainty quantification Gaussian Mixture Models

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Mass elevation effect and its forcing on timberline altitude

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Journal of Geographical Sciences 2012年第4期22卷 609-616页

作者： HAN Fang YAO Yonghui DAI Shibao WANG Chun SUN Ranhao XU Juan ZHANG Baiping Geographic Information and Tourism College Chuzhou UniversityChuzhou 239000AnhuiChina State Key Laboratory of Resource and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental ScienceCASBeijing 100085China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China

The concept of mass elevation effect （massenerhebungseffect, MEE） was introduced by A. de Quervain about 100 years ago to account for the observed tendency for temperature-related parameters such as tree line and snowline to occur at higher elevations in the central Alps than on their outer margins. It also has been widely observed in other areas of the world, but there have not been significant, let alone quantitative, researches on this phenomenon. Especially, it has been usually completely neglected in developing fitting mod- els of timberline elevation, with only longitude or latitude considered as impacting factors. This paper tries to quantify the contribution of MEE to timberline elevation. Considering that the more extensive the land mass and especially the higher the mountain base in the interior of land mass, the greater the mass elevation effect, this paper takes mountain base elevation （MBE） as the magnitude of MEE. We collect 157 data points of timberline elevation, and use their latitude, longitude and MBE as independent variables to build a multiple linear regression equation for timberline elevation in the southeastern Eurasian continent. The results turn out that the contribution of latitude, longitude and MBE to timberline altitude reach 25.11%, 29.43%, and 45.46%, respectively. North of northern latitude 32°, the three factors＇ contribution amount to 48.50%, 24.04%, and 27.46%, respectively; to the south, their contribution is 13.01%, 48.33%, and 38.66%, respectively. This means that MBE, serving as a proxy indi- cator of MEE, is a significant factor determining the elevation of alpine timberline. Compared with other factors, it is more stable and independent in affecting timberline elevation. Of course, the magnitude of the actual MEE is certainly determined by other factors, including mountain area and height, the distance to the edge of a land mass, the structures of the mountains nearby. These factors need to be inctuded in the study of MEE quantification in the future. This paper could hel

关键词： mass elevation effect mountain base elevation altitudinal belts quantification Eurasia

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