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International Journal of minerals,metallurgy and materials 2018年第11期25卷 1335-1343页

作者： Labani mustafi m.m.Rahman mohammad Nur E Alam Al Nasim mohammad Asaduzzaman Chowdhury m.h.monir School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia Dhaka University of Engineering and Technology Gazipur 1707Bangladesh

A systematic investigation was carried out to observe the deposition rate of a diamond-like carbon(DLC) coating on two stainless steel substrates by chemical vapor deposition(CVD). The objective of this research is to study the deposition behavior of the DLC coating and its tribological properties in different combinations of methane(Ch_4) and nitrogen, which were used as precursor gases. The results reveal that the deposition rate increases with increasing Ch_4 content up to 50 vol%. The hardness of the DLC-deposited layer also increases while the friction coefficient decreases with increasing Ch_4 gas content up to 50% in the precursor gas mixture.

关键词： diamond-like carbon chemical vapor deposition methane and nitrogen gas mixtures deposition rate hardness friction coefficient

malaria prevalence in north-eastern Nigeria:A cross-sectional study houben Ch^(1*),Fleischmann h^2,Gǜckel m^3

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Asian Pacific Journal of Tropical medicine 2013年第11期6卷 865-868页

作者： houben Ch Fleischmann h Gckel m Diagnostic Center mmm group & Specialist hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria medical mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to hildren tested positive for *** representing a PfPR2-10 value of 38.4%.malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WhO estimates for 2011.

关键词： malaria control malaria endemicity malaria prevalence malaria transmission

Impact of National Egyptian school feeding program on growth,development,and school achievement of school children

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World Journal of Pediatrics 2020年第4期16卷 393-400页

作者： A.m.metwally marwa m.El-Sonbaty L.A.El Etreby E.m.Salah El-Din N.Abdel hamid h.A.hussien A.m.hassanin Z.m.monir medical Research Division Community Medicine DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Department of Pediatrics College of MedicineTaibah UniversityMadinahKingdom of Saudi Arabia medical Research Division Child Health DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Agricultural Research Centre GizaEgypt

Background School feeding program(SFP)increases access to education and to better *** study aims to evaluate the effects of SFP on physical growth,cognitive development,psychosocial behavior,and learning achievement of school *** A quasi-experimental study was *** intervention group included 903 pupils in the fifth grade receiving the school meal,while the control group included 886 pupils,matched for age and sex,without *** meal consisted of a pie made of flour fortified with vitamins A,B6,B12,C,thiamin,riboflavin,niacin,folate,calcium,iron,zinc,and *** position,nutritional status,and dietary behavior were *** tests were *** behavior was rated and educational achievement was *** hoc and independent sample t tests were used to detect the association of the studied parameters with the intake of school *** Children who took the meal had better scores on visual memory,auditory vigilance tests(9.71±2.80 vs.7.45±3.25;25.02±3.36 vs.10.82±8.92,respectively,Phe afternoon attention and working memory test(8.20±2.21vs.7.75±3.05)(Phavior(Phan the control *** significant changes of children’s nutritional status were detected between the two *** meal was the main predictor of visual memory and auditory vigilance(Phe strongest predictor of academic achievements when combined with family size and meals’frequency(Phool meal improves academic achievements of school children.

关键词： Cognition Growth Performance School feeding

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis h.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

In vitro α-amylase inhibitory activity and in vivo hypoglycemic effect of methanol extract of Citrus macroptera ***

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Asian Pacific Journal of Tropical Biomedicine 2014年第6期4卷 473-479页

作者： Nizam Uddin Rakib hasan monir hossain Arjyabrata Sarker A.h.m.Nazmul hasan A.F.m.mahmudul Islam mohd.motaher h.Chowdhury Sohel Rana Laboratory of Natural Products Research Department of PharmacyJahangirnagar University

Objective:To investigate the therapeutic effects of methanol extract of Citrus macroptera montr,fruit inα-amylase inhibitory activity(in vitro)and hypoglycemic activity in normal and glucose induced hyperglycemic rats(in vivo).methods:Fruits of Citrus macroptera without rind was extracted with pure methanol following cold extraction and tested for presence of phytochemical constituents,α-amylase inhibitory activity,and hypoglycemic effect in normal rats and glucose induced hyperglycemic ***:Presence of saponin,steroid and terpenoid were identified in the *** results showed that fruit extract had moderateα-amylase inhibitory activity[IC_(50)value=(3.638±0.190)mg/mL]as compared to *** at 500 mg/kg and 1000 mg/kg doses fruit extract significantly(Pmal rats as compared to glibenclamide(5 mg/kg).In oral glucose tolerance test,500 mg/kg dose significantly reduced blood glucose level(Ph but 1000 mg/kg dose significantly reduced blood glucose level at 2 h and 3 h(Phereas glibenclamide(5 mg/kg)significantly reduced glucose level at every hour after *** time effect is also considered extremely significant with F value=23.83 and P value=0.0001 in oral glucose tolerance ***:These findings suggest that the plant may be a potential source for the development of new oral hypoglycemic agent.

关键词： Diabetes mellitus hypoglycemic Citrus macroptera α-Amylase OGTT Glibenclamide

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

Analytical model for thermal lensing and spherical aberration in diode side-pumped Nd:YAG laser rod having Gaussian pump profile

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Chinese Physics B 2015年第12期24卷 334-341页

作者： m h moghtader Dindarlu m Kavosh Tehrani h Saghafifar A maleki Institute of Optics and Laser Malek-Ashtar University of Technology

In this paper, according to the temperature and strain distribution obtained by considering the Gaussian pump profile and dependence of physical properties on temperature, we derive an analytical model for refractive index variations of the diode side-pumped Nd：YAG laser rod. Then we evaluate this model by numerical solution and our maximum relative errors are 5% and 10% for variations caused by thermo–optical and thermo–mechanical effects; respectively. Finally, we present an analytical model for calculating the focal length of the thermal lens and spherical aberration. This model is evaluated by experimental results.

关键词： side-pumped laser rod Gaussian pump profile thermal effects thermal lens spherical aberration

microstructure evolution of a recycled Al-Fe-Si-Cu alloy processed by tube channel pressing

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International Journal of minerals,metallurgy and materials 2018年第10期25卷 1166-1172页

作者： m.h.Farshidi m.Rifai h.miyamoto Department of materials Science and metallurgical Engineering Ferdowsi University of Mashhad Department of mechanical Engineering Doshisha University

Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFeSi particles into the alloys' microstructures. One of the well-known methods for modifying the microstructure of metallic materials is the imposition of severe plastic deformation(SPD). Nevertheless, the microstructure evolutions of recycled Al alloys containing extraordinary fractions of AlFeSi particles during SPD processing have seldom been considered. The aim of the present work is to study the microstructure evolution of a recycled Al–Fe–Si–Cu alloy during SPD processing. For this purpose, tubular specimens of the mentioned alloy were subjected to different numbers of passes of a recently developed SPD process called tube channel pressing(TCP); their microstructures were then studied using different techniques. The results show that coarse AlFeSi particles are fragmented into finer particles after processing by TCP. however, decomposition and dissolution of AlFeSi particles through TCP processing are negligible. In addition, TCP processing results in an increase in hardness of the alloy, which is attributed to the refinement of grains, to an increase of the dislocation density, and to the fragmentation of AlFeSi particles.

关键词： AlFeSi intermetallic particle severe plastic deformation microstructure tube channel pressing

Solvability of a class of PT-symmetric non-hermitian hamiltonians：Bethe ansatz method

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Chinese Physics B 2017年第6期26卷 14-21页

作者： m Baradaran h Panahi Department of Physics University of Guilan Rasht 41635-1914Iran

We use the Bethe ansatz method to investigate the Schrdinger equation for a class of PT-symmetric non-hermitian hamiltonians. Elementary exact solutions for the eigenvalues and the corresponding wave functions are obtained in terms of the roots of a set of algebraic equations. Also, it is shown that the problems possess sl（2） hidden symmetry and then the exact solutions of the problems are obtained by employing the representation theory of sl（2） Lie algebra. It is found that the results of the two methods are the same.

关键词： PT-symmetry Bethe ansatz method Lie algebraic approach quasi-exactly solvable

A STABILITY ThEOREm FOR CONSTRAINED OPTImAL CONTROL PROBLEmS

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Journal of Computational mathematics 2004年第5期22卷 633-640页

作者： m.h.Farag DepartmentofmathematicsandComputerScienceFacultyofEducation lbriSultanateofOman

This paper presents the stability of difference approximations of an optimal control problem for a quasilinear parabolic equation with controls in the coefficients, boundary conditions and additional restrictions. The optimal control problem has been convered to one of the optimization problem using a penalty function technique. The difference approximations problem for the considered problem is obtained. The estimations of stability of the solution of difference approximations problem are proved. The stability estimation of the solution of difference approximations problem by the controls is obtained.

关键词： Optimal control Quasilinear Parabolic equations Penalty function methods Finite difference method Stability estimations