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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 458-464页

作者： Bereket Alemayehu Zewdneh Tomass Wolaita Sodo University College of Natural and Computational SciencesDepartment of BiologyBiomedical Science Division

Objective:To establish the prevalence and associated risk factors of Schistosoma mansoni(S.mansoni) infection among schoolchildren at a village in Wolaita Zone.Sothern Ethiopia,Methods:A cross-sectional study was carried out among primary schoolchildren.A total of 384 randomly selected study subjects provided stool samples for parasitological examination by Kato-Katz and Formalin-Ether concentration techniques.Secondary parasitological data were obtained from Health Center Laboratory to see the previous history of.S.mansoni infection in the area.Statistical analysis was performed using SPSS software version 16.Results:From the total children examined.85.4% were found positive for at least one helminth infection.S.mansoni infection(81.3% ) was the most prevalent and the prevalence of STH was 32% ..Moderate and heavy infection intensities were only observed in S,mansoni infections.The overall heavy intensity of infection was 56.4% .Contact to Bisarc stream was the most important factor for S.mansoni infection(OR 3.9) followed by herding cattle near the stream(OR2.527).Males were twice more likely to get the infection than females(OR 1.923).Analysis of secondary parasitological data showed that S.mansoni infection was a leading helminthic infection over the past years.Conclusions:The present study found a higher intensity and prevalence of S.mansoni infection in a rural village of Wolaita Zone.Therefore,appropriate integrated control and prevention measures need to be implemented in the study area.

关键词： Schistosoma mansoni Parasite Schoolchildren Wolaita Zone Ethiopia

Evaluation of Beta-Lactam Antibiotics on the Regeneration of Peanut Plants and Their Inhibitory Effect on Agrobacterium Growth

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Phyton-International Journal of Experimental Botany 2023年第9期92卷 2489-2501页

作者： Abraham Lamboro Songnan Yang Xueying Li Dan Yao Jun Zhang college of Agronomy Jilin Agricultural UniversityChangchun130118China college of Life science Jilin Agricultural UniversityChangchun130118China Department of Biology College of Natural and Computational ScienceWachemo UniversityHossana667Ethiopia

The effect of beta-lactam antibiotics on shoot induction and plantlet regeneration from cotyledonary nodes was tested using two peanut cultivars.The culture media contained 4 mg/L 6-benzylaminopurine(BAP)as the main growth regulator.Various concentrations(100–600 mg/L)of cefotaxime,carbenicillin,and timentin were applied in the culture media.In all the tested media,there were no significant differences in the shoot induction as compared to the control.However,little phytotoxic effect was observed at higher concentrations of these antibiotics in the shoot elongation media.Under shoot elongation medium,shoots turned brownish and partly died at higher concentrations where shooting rates were not affected by the treatments.In cefotaxime,timentin,and carbenicillin-containing media,levels of antibiotics greater than 400,300,and 200 mg/L,respectively resulted in the brown coloration of plantlets.Moreover,the mean shoot number and shoot weight significantly decreased as their dosage increased.The results indicate that maximum levels of antibiotics have an adverse effect on the growth and development of peanuts.Also,cefotaxime(100–300 mg/L)and timentin(100–300 mg/L)will be sufficient in controlling Agrobacterium growth in the culture media with the least phytotoxic effect on the peanut plants.

关键词： Peanut antibiotics shoot cotyledonary node regeneration

Allometric equations for aboveground biomass estimation of Olea europaea L.subsp.cuspidata in Mana Angetu Forest

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Ecosystem Health and Sustainability 2018年第1期4卷 1-13页

作者： Birhanu Kebede Teshome Soromessa Center for Environmental science College of Natural and Computational SciencesAddis Ababa UniversityAddis AbabaEthiopia

Introduction:African wild olive,Olea europaea L.subsp.cuspidata(Wall.ex G.Don)Cif.,L‘Olivicoltore is widely distributed in dry forest and forest margins,often with Juniperus procera,in east Africa and Ethiopia.It reaches southern Africa,also India and China,ranging from tall trees to stunted shrubs.Does best in good forest soil,but hardy and drought resistant once established,even in poor soils.It is used for firewood,charcoal,poles,posts,timber(furniture,carving,floors,and paneling),medicine(stem,bark,and leaves),bee forage,milk flavoring(smoking wood),toothbrushes(twigs),and walking sticks.Although the species has many economic and ecological functions,its environmental uses like carbon storage and climate change mitigation are less assessed.Therefore,the objective of the study was to develop species-specific allometric equations for O.europaea L.subsp.cuspidata using semi-destructive method and evaluate allometric models for estimating the aboveground biomass(AGB).Results and Discussions:After all the necessary biomass calculations were done,seven AGB equations were developed.These regression equations relate AGB with diameter at breast height(DBH),height(H),and density(ρ)individually and in combination.Out of seven,four allometric equations were chosen based on goodness-of-fit statistics and three were rejected.The selected models were tested for accuracy based on observed data.The best models selected have higher R2-adj and lower residual standard error and Akaike information criterion than rejected equations.The relations for all selectedmodels are significant(p<0.000),which showed strong correlation of AGB with selected dendrometric variables.Accordingly,the AGB was strongly correlated with DBH and was not significantly correlated with wood density and height individually in O.europaea L.subsp.cuspidata allometric equation development.In combination,AGB was strongly correlated with DBH and height;DBH and wood density;and the combination of DBH,height,and wood density.Species-specific equations are used for

关键词： AGB allometricequation biomass estimation Mana Angetu Forest Olea europaea subsp.cuspidata

Trimetallic nanostructures and their applications in electrocatalytic energy conversions

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Journal of Energy Chemistry 2022年第2期31卷 329-351页

作者： Shushay Hagos Gebre Marshet Getaye Sendeku College of Natural and Computational Science Department of ChemistryJigjiga University1020 JigjigaEthiopia CAS Center for Excellence in Nanoscience CAS Key Laboratory of Nanosystem and Hierarchical FabricationNational Center for Nanoscience and TechnologyBeijing 100190China

The advancement and growth of nanotechnology lead to realizing new and novel multi-metallic nanostructures with well-defined sizes and morphology,resulting in an improvement in their performance in various catalytic applications.The trimetallic nanostructured materials are synthesized and designed in different architectures for energy conversion electrocatalysis.The as-synthesized trimetallic nanostructures have found unique physiochemical properties due to the synergistic combination of the three different metals in their structures.A vast array of approaches such as hydrothermal,solvothermal,seedgrowth,galvanic replacement reaction,biological,and other methods are employed to synthesize the trimetallic nanostructures.Noteworthy,the trimetallic nanostructures showed better performance and durability in the electrocatalytic fuel cells.In the present review,we provide a comprehensive overview of the recent strategies employed for synthesizing trimetallic nanostructures and their energy-related applications.With a particular focus on hydrogen evolution,alcohol oxidations,oxygen evolution,and others,we highlight the latest achievements in the field.

关键词： Trimetallic nanoparticle Electrooxidation Electrocatalysis Alloy Energy conversion

Regularity for minimizing sequences of some variational integrals

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science China Mathematics 2023年第4期66卷 777-798页

作者： Hongya Gao Yanan Shan Wei Ren Hebei Key Laboratory of Machine Learning and computational Intelligence College of Mathematics and Information ScienceHebei UniversityBaoding 071002China

This paper deals with regularity properties for minimizing sequences of some integral functionals related to the nonlinear elasticity theory.Under some structural conditions,we derive that the minimizing sequence and ... 详细信息

关键词： regularity minimizing sequence variational integral energy Ekeland variational principle

Deterministic epidemic model for (SVC_(Sy)C_(Asy)IR) pneumonia dynamics, with vaccination and temporal immunity

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Infectious Disease Modelling 2020年第1期5卷 42-60页

作者： Dominic Otoo Patrick Opoku Sebil Charles Asekiya Prince Kingsley Department of Mathematics&Statistics School of ScienceUniversity of Energy&Natural ResourcesSunyaniGhana Department of Mathematics Faculty of Physical and Computational ScienceCollege of ScienceKwame Nkrumah University of Science&TechnologyKumasiGhana

Streptococcus pneumonia is one of the leading causes of mobility and mortality in children under 6 years and the elderly especially in developing countries in which Ghana,the study area is not an exception.In this paper,a model of the spread and control of bacterial pneumonia that include symptomatic carriers,asymptomatic carriers and vaccination is formulated and analyzed to determine the effect of the vaccination intervention.Analysis of the system show that the disease free equilibrium is stable if and only if the basic reproductive number R0<1.For R01,the endemic equilibrium is globally stable and the disease persist.Numerical simulation on the system show that with effective vaccine intervention pneumonia infection can be eradicated in the long term.

关键词： Asymptomatic carriers Morbidity Mortality Pneumonia Symptomatic carriers Vaccination

Synthesis and characterization of high strength polyimide/silicon nitride nanocomposites with enhanced thermal and hydrophobic properties

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Chinese Journal of Chemical Engineering 2021年第4期34卷 446-453页

作者： Tadele Daniel Mekuria Lei Wang Chunhong Zhang Ming Yang Qingtao Lv Diaa Eldin Fouad Polymer Materials Research Center Key Laboratory of Superlight Materials and Surface TechnologyMinistry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Chemistry Department College of Natural and Computational SciencesAssosa UniversityEthiopia

Polyimide(PI)composite films were synthesized incorporating amino modified silicon nitride(Si_(3)N_(4))nanoparticles into PI matrix via in situ polymerization technique.The mechanical and thermal performances as well as the hydrophobic properties of the as prepared composite films were investigated with respect to the dosage of the filler in the PI matrix.According to Thermogravimetric(TGA)analysis,meaningful improvements were achieved in T5(5%weight loss temperature)and T10(10%weight loss temperature)up to 54.1℃ and 52.4℃,respectively when amino functionalized nano Si_(3)N_(4) particles were introduced into the PI matrix.The differential scanning calorimetry(DSC)results revealed that the glass transition temperature(Tg)of the composites was considerably enhanced up to 49.7℃ when amino functionalized Si_(3)N_(4) nanoparticles were incorporated in the PI matrix.Compared to the neat PI,the PI/Si_(3)N_(4) nanocomposites exhibited very high improvement in the tensile strength as well as Young’s modulus up to 105.4%and 138.3%,respectively.Compared to the neat PI,the composites demonstrated highly decreased water absorption behavior which showed about 68.1%enhancement as the content of the nanoparticles was increased to 10 wt%.The SEM(Scanning electron microscope)images confirmed that the enhanced thermal,mechanical and water proof properties are essentially attributed to the improved compatibility of the filler with the matrix and hence,enhanced distribution inside the matrix because of the amino groups on the surface of Si_(3)N_(4) nanoparticles obtained from surface functionalization.

关键词： Silicon nitride(Si_(3)N_(4))nanoparticles Polyimide composites Mechanical properties Thermal properties Hydrophobicity

Boundedness and Spectrum of Multiplicative Convolution Operators Induced by Arithmetic Functions

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1300-1310页

作者： Kibrom G.EBREMESKEL Lin Zhe HUANG Academy of Mathematics and Systems science Chinese Academy of SciencesBeijing 100190P.R.China Department of Mathematics College of Natural and Computational SciencesAksum UniversityAksumTigrayEthiopia

In this paper, we consider a multiplicative convolution operator Mf acting on a Hilbert spaces l^2(N,ω;). In particular, we focus on the operators M1 and Mμ, where μ, is the Mobius function. We investigate conditions on the weight ω under which the operators M1 and Mμ are bounded. We show that for a positive and completely multiplicative function f,M1 is bounded on l^2(N, f^2) if and only if ||f||1 1. As an application, we obtain some results on the spectrum of M1^*M1 and M^*μMμ. Moreover, von Neumann algebra generated by a certain family of bounded operators is also considered.

关键词： Arithmetic functions Mobius function von Neumann algebra

Quasi-optimal complexity of adaptive finite element method for linear elasticity problems in two dimensions

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Applied Mathematics and Mechanics(English Edition) 2016年第2期37卷 151-168页

作者： Chunmei LIU Liuqiang ZHONG Shi SHU Yingxiong XIAO Institute for computational Mathematics College of Science Hunan University of Science and Engineering School of Mathematical sciences South China Normal University School of Mathematics and computational science Xiangtan University college of Civil Engineering and Mechanics Xiangtan University

This paper introduces an adaptive finite element method （AFEM） using the newest vertex bisection and marking exclusively according to the error estimator without special treatment of oscillation. By the combination of the global lower bound and the localized upper bound of the posteriori error estimator, perturbation of oscillation, and cardinality of the marked element set, it is proved that the AFEM is quasi-optimal for linear elasticity problems in two dimensions, and this conclusion is verified by the numerical examples.

关键词： linear elasticity problem adaptive finite element method （AFEM） quasioptimal complexity

First-order optimality condition of basis pursuit denoise problem

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Applied Mathematics and Mechanics(English Edition) 2014年第10期35卷 1345-1352页

作者：朱玮舒适成礼智 School of Mathematics and computational science Xiangtan University Hunan Key Laboratory for Computation and Simulation in science and Engineering Xiangtan University Department of Mathematics and computational science College of ScienceNational University of Defense Technology

A new first-order optimality condition for the basis pursuit denoise （BPDN） problem is derived. This condition provides a new approach to choose the penalty param- eters adaptively for a fixed point iteration algorithm. Meanwhile, the result is extended to matrix completion which is a new field on the heel of the compressed sensing. The numerical experiments of sparse vector recovery and low-rank matrix completion show validity of the theoretic results.

关键词： basis pursuit denoise （BPDN） fixed point iteration first-order optimality,matrix completion