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Optoelectronics Letters 2020年第5期16卷 369-372页

作者： S.Alsheikh Salo B.Abdallah m.Akel m.Kakhia S.Alsheikh Salo B.AbdallahM.AkelM.Kakhia Department of PhysicsAtomic Energy CommissionDamascus P.O.Box 6091Syria1

The chromium(Cr)films on silicon Si(100)substrate are prepared using DC magnetron sputtering technique at an argon gas pressure of 3 Torr for different applied powers(40—140 W).The chemical composition,the thicknesses and the structural characterization of the deposited Cr films are studied and analyzed using energy dispersive X-ray spectroscopy(EDX),scanning electron microscopy(SEm),and X-ray diffraction(XRD),***,the generated plasma parameters,including floating potential,plasma potential,electron density,ion density and electron temperature,have been measured,and the automated Langmuir probe is used for the Cr films *** ion and metal fluxes are also *** results show that the Cr film thickness enhances with the higher applied *** Cr deposited films properties are characterized and correlated with the measured plasma parameters.

关键词： deposited chromium film

Prediction of flyrock in open pit blasting operation using machine learning method

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International Journal of mining Science and Technology 2013年第3期23卷 313-316页

作者： manoj Khandelwal m. monjezi Department of mining Engineering College of Technology & Engineering Maharana Pratap University of Agriculture and Technology Faculty of Engineering Tarbiat Modares University

Flyrock is one of the most hazardous events in blasting operation of surface mines. There are several empirical methods to predict flyrock. Low performance of such models is due to the complexity of flyrock analysis. Existence of various effective parameters and their unknown relationships are the main reasons for inaccuracy of the empirical models. Presently, the application of new approaches such as artificial intelligence is highly recommended. In this paper, an attempt has been made to predict flyrock in blasting operations of Soungun Copper mine, Iran incorporating rock properties and blast design parameters using support vector machine (SVm) method. To investigate the suitability of this approach, the predictions by SVm have been compared with multivariate regression analysis (mVRA), too. Coefficient of determination (CoD) and mean absolute error (mAE) were taken as performance measures. It was found that CoD between measured and predicted flyrock was 0.948 and 0.440 by SVm and mVRA, respectively, whereas mAE between measured and predicted flyrock was 3.11 and 7.74 by SVm and mVRA, respectively.

关键词： Blasting Soungun Copper mine Flyrock Support vector machine mVRA

Low dose oral haloperidol does not prolong QTc interval in older acutely hospitalised adults： a subanalysis of a randomised double-blind placebo-controlled study

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Journal of Geriatric Cardiology 2018年第6期15卷 401-407页

作者： Edmee Jm Schrijver maaike Verstraaten Peter m van de Ven Pierre m Bet Astrid m van Strien Carel de Cock Prabath WB Nanayakkara on behalf of all HARPOON Investigators Department of Internal medicine VU University Medical Centre Amsterdam the Netherlands Department of Cardiology VU University Medical Centre Amsterdam the Netherlands Department of Epidemiology and Biostatistics VU University Medical Centre the Netherlands Department of Clinical Pharmacology and Pharmacy VU University Medical Centre the Netherlands Department of Geriatric medicine Jeroen Bosch Hospital s-Hertogenbosch the Netherlands

Background Haloperidol is the most frequently prescribed antipsycbotic for delirium symptoms. The risk of QTc prolongation often raises concerns, although the effect of haloperidol on QTc interval has not yet been investigated in a randomised placebo-controlled fixed-dose study. methods A subanalysis of a randomised double-blind placebo-controlled study was conducted to evaluate the effect of prophylactic haloperidol 1 mg or placebo 1 mg orally twice-daily （maximum of 14 doses） on QTc interval in patients aged 70 years and over. Bedside, 12-lead ECGs were recorded before, during and after the one-week intervention period. Automatic QTc measurements were ob- tained in addition to manual measurements of QT and RR intervals, blinded for treatment status. manual measurements were corrected （QTc） using Bazett （QTc-B）, Framingham （QTc-Fa）, Fridericia （QTc-Fi） and Hodges （QTc-H） methods. mixed model analyses were used to test for differences in longitudinal course of QTc between patients receiving haloperidol and placebo. Results ECG recordings of 72 patients （haloperidol n = 38） were analysed, 45.8% male. median （range） haloperidol serum concentration on day 4 was 0.71 （0.32-1.82） μg/L （n = 23）. Longitudinal course of mean QTc did not significantly differ between treatment arms for any of the automatic or manually derived QTc values. Conclusions Low dose oral haloperidol did not result in QTc prolongation in older acutely hospitalised patients. Results may not be generalizable to patients with existing ECG abnormalities such as atrial fibrillation.

关键词： Haloperidol Prolongation QTc interval The aged

In-situ alloyed CoCrFemnNi high entropy alloy:microstructural development in laser powder bed fusion

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Journal of materials Science & Technology 2022年第28期123卷 123-135页

作者： Peng Chen Xiyu Yao moataz m.Attallah ming Yan Department of materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Advanced materials Processing Laboratory University of BirminghamBirmingham B152TTUK

In-situ alloying has the potential to combine the compositional flexibility of high entropy alloys(HEAs)and the advanced forming capability of laser powder bed fusion(LPBF).This study fundamentally investigated the elemental homogenisation and grain development in the in-situ alloying process of CoCrFemnNi HEA,by analysing the basic units,i.e.,tracks and layers,and introducing mn as an alloying element to the base Co Cr Fe Ni *** modelling methods were employed to predict meltpool dimensions,and the results indicated the dependence of the modelling on practical meltpool *** of elemental distribution was found in keyhole meltpools since an intensive flow was generated due to recoil *** homogeneity of in-situ alloyed mn in single tracks was insufficient whether operated in conduction mode or keyhole mode,which required remelting from adjacent tracks and following layers to promote homogenisation *** preferred orientation in single tracks along scanning directions changed fromtoas the scanning speed increased,although the cross-sections were similar in size with identical linear energy *** preference can be inherited during the printing process and lead to different textures in three-layer *** was also observed that applying hatch spacing smaller than a half meltpool width could coarsen the grains in a *** results from this study provide structure-parameter correlations for future microstructural tailoring and manipulation.

关键词： Laser powder bed fusion High entropy alloy In-situ alloying Single track Elemental homogenisation

microglia-precursor cell interactions in health and in pathology

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BIOCELL 2018年第2期42卷 41-45页

作者： Estela m.mUÑOZ Instituto de Histología y Embriología de mendoza Dr.mario H.Burgos(IHEm) Universidad Nacional de Cuyo(UNCuyo)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)MendozaArgentina

Until recently,microglia were mainly known as the resident phagocytes of the brain,***‘immunological warriors’of the ***,extensive knowledge is being accumulated about the functions of microglia beyond ***,it is well accepted that microglial cells are highly dynamic and responsive,and that they intervene in a dual manner in many developmental processes that shape the central nervous system,including neurogenesis,gliogenesis,spatial patterning,synaptic formation and elimination,and neural circuit establishment and *** differentiation and the pool of precursor cells were also shown to be under microglia regulation via bidirectional *** this concise review,I discuss our recent work in microglia-Pax6+cell interactions in one of the circumventricular organs,the pineal *** analogy with the rest of the central nervous system is also *** addition,I briefly examine mechanisms of interaction between microglia and non-microglial cells in both health and *** avenues are also introduced,which may lead us to better comprehend the impact of microglia in physiological and pathological conditions.

关键词： Phagocyte Phagocytosis Phagoptosis Apoptosis Autophagy

molecular dynamics simulation of the Stribeck curve: Boundary lubrication, mixed lubrication, and hydrodynamic lubrication on the atomistic level

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摩擦:英文版 2023年第12期11卷 2342-2366页

作者： Simon STEPHAN Sebastian SCHmITT Hans HASSE Herbert m.URBASSEK Laboratory of Engineering Thermodynamics(LTD) Department of Mechanical and Process EngieeringTU KaiserslauternRheinland-Pfalz 67663Germany Physics Department and Research Center(OPTImAS) TU KaiserslauternRheinland-Pfalz 67663Germany

Lubricated contact processes are studied using classical molecular dynamics simulations for determining the entire range of the Stribeck ***,the lateral movement of two solid bodies at different gap height are *** each simulation,a rigid asperity is moved at constant height above a flat iron surface in a lubricating *** methane and decane are considered as *** three main lubrication regimes of the Stribeck curve and their transition regions are covered by the study:Boundary lubrication(significant elastic and plastic deformation of the substrate),mixed lubrication(adsorbed fluid layer dominates the process),and hydrodynamic lubrication(shear flow is set up between the surface and the asperity).We find the formation of a tribofilm in which lubricant molecules are immersed into the metal surface—not only in the case of scratching,but also for boundary lubrication and mixed *** formation of a tribofilm is found to have important consequences for the contact ***,the two fluids are found to show distinctly different behavior in the three lubrication regimes:For hydrodynamic lubrication(large gap height),decane yields a better tribological performance;for boundary lubrication(small gap height),decane shows a larger friction coefficient than methane,which is due to the different mechanisms observed for the formation of the tribofilm;the mixed lubrication regime can be considered as a transition regime between the two other ***,it is found that the nature of the tribofilm depends on the lubricant:While methane particles substitute substrate atoms sustaining mostly the crystalline structure,the decane molecules distort the substrate surface and an amorphous tribofilm is formed.

关键词： boundary lubrication mixed lubrication hydrodynamic lubrication molecular dynamics simulation tribofilm

SCOUR mITIGATION AT BRIDGE PIERS USING SACRIFICIAL PILES

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International Journal of Sediment Research 2007年第1期22卷 49-59页

作者： m. Anisul HAQUE md. munsur RAHmAN G.m. Tarekul ISLAm m. Asad HUSSAIN Prof.Institute of Water and Flood management (IWFm) Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh Assoc. Prof.Institute of Water and Flood management (IWFm) Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh Lecturer Institute of Water and Flood Management (IWFM) Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh

To mitigate scour around bridge piers, sacrificial piles are economic method where natural processes are involved. The arrangement should be such that scoured materials from the sacrificial piles should have enough volume to fill the scour hole created upstream of the pier in such a way that sediments are trapped inside the scour hole. This concept differs from earlier study made with sacrificial piles that mainly deals to reduce the strength of horseshoe vortex. To determine the effect of sacrificial piles for scour mitigation, alternative arrangements of piles were tested in front of a rectangular pier under clear-water condition and found that when the group of piles is placed at a distance of twice the projected width of the pier, for which percentage of blockage of the pier width is 60%, the scour volume can be reduced upto 61% while the maximum scour depth can be reduced upto 50%.

关键词： Scour mitigation Bridge pier Sacrificial pile Optimum arrangement

Antibiotic Resistance Profile of Enterococcus faecalis and Enterococcus faecium Isolates from Urine and Pleural Fluid in Two Hospitals of Cameroon

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Open Journal of medical microbiology 2024年第1期14卷 39-49页

作者： Cécile Ingrid Djuikoue Farid Wega Grace Yemina Kombeu Cedric Seugnou Nana Christiane Possi Kiyang Lussabella Pohoko medzam Erica megane Noubissi makougoum Nellie mbianga Nkuigoua Herman Koyouo Tagne mérimé Joël Tchinda Talokou Yvonne Valérie Yolande mavoungou Ashu michel Agbor microbiology Department of the Faculty of Health Sciences of the Université des montagnes Bangangté Cameroon Faculty of medicine and Pharmaceutical Sciences University of Douala Douala Cameroon microbiology Department of the Faculty of Health Sciences of Institut Universitaire du Golf de Guinée Douala Cameroon Centre Hospitalier Dominicain St martin de Porres Yaoundé Cameroun Faculté des Sciences de la Santé Université Marien Ngouabi Brazzaville République du Congo

Enterococcus faecalis and Enterococcus faecium rank among the leading causes of nosocomial bacteremia and urinary tract infections. They often persist on hospital surfaces due to their ability to withstand adverse environmental conditions (low or high temperatures, high pH, and high salinity). The global Enterococcus faecalis-Enterococcus faecium ratio is currently shifting towards Enterococcus faecium. Enterococci present variable levels of resistance to certain families of antibiotics. This is the case for aminoglycosides, beta-lactams and cephalosporins. In 2017, WHO ranked Enterococci among priority pathogens for research and development of new antibiotics. The objective of our study was to determine the antibiotic resistance profile of Enterococcus faecalis and Enterococcus faecium isolates from urine and pleural fluid in two hospitals in Cameroon. This cross-sectional and analytic study was carried out between June to August 2023 on hospitalized and day patients in which a cytobacteriological test of urine and pleural fluid was done. The samples were inoculated on CLED Agar for urine and on Chocolate + polyvitex and blood agar (prepared from Columbia agar) for pleural fluid samples and incubated at 37℃ for 18 to 24 hours. Identification of isolates was carried out using the API 20 STREP micro gallery (Biomerieux, France) and tested for antimicrobial susceptibility. The data on socio-demographical and potential risk factors were recorded using self-administered questionnaires and data from laboratory analyses of the specimen were collected in a data capture sheet. Potential risk factors associated with the presence of Enterococci, were evaluated using the logistic regression in univariate and multivariate analysis. P value minantly females. Enterococcus spp were isolated in 27.79% of our samples with Enterococcus faecalis mostly encountered. Enterococcus spp showed a high

关键词： Enterococcus faecalis Enterococcus faecium Healthcare-Associated Infections Antimicrobial Resistance Cameroon

Dissipation of chlorpyrifos, pendimethalin, and thiophanate-methyl pesticides in compost based-versus peat-moss based-biomixture of biobeds

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Waste Disposal and Sustainable Energy 2023年第4期5卷 461-470页

作者： Talaat N.m.El-Sebai Wafaa m.H.Zidan Alaa marzouk marion Divers Fabrice martin-Laurent Agricultural microbiology Dept.Agricultural and Biology Research Institute National Research CentreCairoEgypt Laboratory of Pesticide Analysis Agriculture Research CentreCairoEgypt Laboratory of Soil microbiology National Institute of Agricultural ResearchDijonFrance

Biobed is a smart bioremediation system used to treat point-source pesticide *** is the main component of biobeds,and pesticide dissipation is affected by its *** study aimed to compare the effectiveness of compost-based(C)versus peat-moss-based(P)biomixtures of biobeds on tested pesticide *** concentrations(25,50,and 75 mg/kg)of chlorpyrifos,pendimethalin,and thiophanate methyl were added separately and as a mix to both biomixtures C and *** data showed the effect of biomixture type on the dissipation of the tested *** chlorpyrifos,its dissipation rate in biomixture P was more rapid than that in biomixture *** result was confirmed by the mineralization kinetic experiment,since 25%of the initial ^(14)C-chlorpyrifos concentration accumulated in the form ^(14)CO_(2) in biomixture P compared to only 14%in biomixture *** addition,the chlorpyrifos dissipation rate was influenced by the initial concentration when applied individually in biomixture *** contrast,biomixture C was more effective at pendimethalin dissipation than biomixture P,since>76%of pendimethalin was dissipated in biomixture C versus 67%in biomixture P at the same incubation *** thiophanate-methyl,the abilities of both biomixtures C and P were similar and less efficient than those of the other tested *** addition of the three tested pesticides to biomixture C only had a positive effect on both chlorpyrifos and thiophanate-methyl dissipation,while pendimethalin dissipation was similar when applied separately or as a *** activity was stimulated by the addition of separately or mixed pesticides to biomixtures C and P as measured by dehydrogenase activity.

关键词： Biopurification system Pesticides Contamination Point-source Bioremediation Biomixture

Conjugated microporous polymer membranes for chemical separations

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Chinese Journal of Chemical Engineering 2022年第5期35卷 1-14页

作者： Zongyao Zhou Zhen Li Lubna m.Rehman Zhiping Lai Division of Physical Science and Engineering King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Conjugated microporous polymers(CmPs) are a unique class of porous organic materials, which are constructed with π-conjugation structures leading to intrinsic micropores. The CmPs properties such as high surface area, intrinsic and rich micropores, interlocking and rigid structure, extensive π-conjugation and tunable band-gap, chemical and thermal stability, together with tailored functionalities, contribute to its abundant potential for application in fields such as photocatalysis, optoelectronics, energy storage, and chemical sensors. Recently, CmPs have gained importance in the field of membranes for chemical separation. In this review, we briefly discuss the historical development of CmPs, followed by a detailed description of the progress in state-of-the-art design, preparation, and application of CmPs in membranes. Additionally, we provide inference on the future prospects of CmPs as membranes.

关键词： Conjugated microporous polymer membrane Separation Electropolymerization Film