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Assessment of retention Ponds and Its Impacts on Health of Residents in Mogadishu, Somalia: Mixed Methods

Journal of Water Resource and Protection 2024年第4期16卷 293-307页

作者： Mohamed Ahmed Kullane Mohamed Ibrahim Abdi-Soojeede Faculty of Agriculture and Veterinary Science at Somalia University (Uniso) Mogadishu Somalia Department of Environment at Somalia University (Uniso) Mogadishu Somalia

The purpose of this study was to evaluate the effects of retention ponds on the environment and population health by analyzing water samples from various ponds in Mogadishu, to determine the prevalence of waterborne illnesses that occur during the rainy season in Mogadishu, and to find out what experts thought about the effects of retention ponds on the environment as well as population health in Mogadishu. Methods: Mixed designs were used in the study. The first design is an exploratory study where samples are taken from different retention ponds in Mogadishu. The second design involves gathering secondary data from the online FSNAU Dashboard regarding the incidence of rainfall and waterborne illnesses including malaria and cholera. Additionally, a cross-sectional survey of expert opinions using questionnaires was the third design. The 10 water samples were taken from retention ponds in Mogadishu as part of the sample size. Data on the fourth month was also gathered using the FNSAU dashboard, and seventy sample sizes were used for the expert self-administered questionnaire for the third design. Excel was used for data analysis in the initial design. While BMI SPSS versions 22 were used to analyze the data from the Self-administered Questionnaire, additional methods were utilized to compute descriptive statistics, such as mean and standard deviation, and to analyze demographic data in a frequency table. Findings: The results show that three samples had unsatisfactory scores (Grade D): Yaqshid (Warshadda Bastada) had a WQI of 80.85, Boondheer (Bondher Pond) had a WQI of 80.64, and Wartanabad (Xamar Jadiid Pond) had a WQI of 80.89. The remaining samples were all rated as fair (grade), which indicates that they ranged from 50 to 75. The months with the largest rainfall already occurred in December, November, and October, when the prevalence of diseases during the rainy season was highest for cholera cases. Although October and December saw a significant number of malaria cases, November did not. retention ponds’ ove

关键词： retention Ponds Contamination Water Quality Index Waterborne Diseases Mogadishu Somalia

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Determination of the standardized ileal digestible calcium requirement of Ross broilers from hatch to day 14 post-hatch

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Animal Nutrition 2024年第1期16卷 122-129页

作者： Carrie L.Walk Raffaella Aureli Pauline Jenn DSM Nutritional Products Research Center for Animal Nutrition and Health DSM Nutritional Products

An experiment was conducted to determine the standardized ileal digestible (SID) calcium requirement of fast-growing broilers from hatch to d 14 post-hatch.Ross 308 (n=360) male broilers were obtained on day of hatch and allocated to 1 of 5 treatments in battery cages.There were 6 birds per cage and 12 pens per treatment.Four treatments were formulated to contain 0.60%,0.46%,0.32% or 0.18% SID Ca.The final treatment was formulated using total Ca to meet or exceed all nutrient requirements,including 0.90% total Ca and 0.49% non-phytate P (nPP),using the same ingredients.This treatment was the reference diet for comparison and validation of the SID Ca diets.Birds and feed were weighed at placement and on d 14.Tibias and ileal contents were obtained on d 14 and excreta was collected per pen and pooled on d 14.Data were analyzed using JMP Pro and requirements were estimated using 3different non-linear regression models.Increasing the SID Ca content in the diet from 0.18% to 0.60% improved (quadratic,P<0.05) body weight gain and mortality corrected feed conversion ratio (mFCR).The estimated SID Ca requirement to optimize gain or m FCR was between 0.39% and 0.52%.Tibia ash percent and weight increased (quadratic,P<0.05) as SID Ca content in the diet increased and the estimated SID Ca requirement was between 0.32% and 0.58%.Phosphorus utilization was improved in birds fed diets formulated using SID Ca compared with birds fed the reference diet.In conclusion,the SID Ca requirement of fast-growing broilers from hatch to d 14 was estimated between 0.534% and 0.398% when quadratic,straight-broken line,or quadratic-broken line regressions were used.These results agree with previously published data evaluating the SID Ca requirement of fast-growth broilers from hatch to d 10.

关键词： Apparent ileal digestibility Digestible calcium Requirements retention Tibia ash

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Investigation of electrostatically tunable adhesion and instability of flying head slider

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Friction 2024年第3期12卷 462-473页

作者： Fan ZHANG Yu WANG Yueqiang HU Mingquan ZHANG Baotong LI School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China National Engineering Research Center for High Efficiency Grinding College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

The interfacial adhesion between microstructures is inevitable in a micro-electro-mechanical system(e.g.,hard disk drive(HDD)),which may lead to complicated microtribodynamics problems.This research has investigated the effect of surface potential on the interfacial adhesion and microtribodynamics of the head–disk interface(HDI)in an HDD.A dynamic continuum surface force model,where the electrowetting is considered,is proposed to evaluate the interfacial interaction,and then employed into a two-degree-of-freedom(2DOF)model to theoretically analyze the potential influence mechanism on the microtribodynamics.The results confirm that the elimination of potential can effectively repress the adhesion retention,which is further proved by the measured slider response with a laser Doppler vibrometer(LDV).Moreover,the effect of the potential on the adhesion-induced instability is also analyzed through the phase portrait.It tells that the critical stable flying height can be lowered with the elimination of potential.

关键词： electric field(EF) retention instability adhesion

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High retention volume covalent organic polymer for xenon capture:Dynamic separation of Xe and Kr

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Green Energy & Environment 2022年第5期7卷 948-956页

作者： Qian Wang Zhu Meng Juntao Li Shuming Peng Zhonghua Xiang Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyangSichuan621900China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Department of Chemistry Imperial College London20 Gordon StreetLondonWC1H0AJUK Department of Chemistry University College LondonLondonW120BZUK

Xenon capture and Xe/Kr separation are important processes in industry.For instance,Xe/Kr separation is an indispensable step in recycle and treatment of nuclear fuel emission.Among different separation methods,selectively adsorb gas molecules using porous materials is a promising way to reduce the high energy consumption in traditional cryogenic distillation.However,many reported adsorbents still face the challenges of:ⅰ) poor separation property at low Xe/Kr concentrations;ⅱ) insufficient retention volumes,which influence the viability of whole process.In this work,we present a stable covalent organic polymer,i.e.,COP-14,showing promising potential for Xe/Kr separiton.In dynamic breakthrough experiments,COP-14 successfully separates low concentration Xe(350 ppm) and Kr(35 ppm) from target gas mixtures.Meanwhile,the xenon retention volume per gram(1700 mL g^(-1) at 298 K) of COP-14 in dynamics absorption process achieves 3.8 times of benchmark active carbon.The good performance of the newly devloped COP-14 mainly from its rich nitrogen sites and suitable pore size with xenon molecues.The promising results of COP-14 on Xe/Kr separation in this work provide a promising way for designing efficient Xe/Kr separation mateirals.

关键词： process separation retention

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Escaping alveolar macrophage endosomal retention explains massive expansion of SARS-CoV-2 delta variant

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Signal Transduction and Targeted Therapy 2022年第1期7卷 28-30页

作者： Zhenfeng Wang Yabo Zhou Linlin Bao Dan Li Jiadi Lv Dianheng Wang Shunshun Li Wei-Min Tong Jiangning Liu Chuan Qin Bo Huang Department of Immunology&National Key Laboratory of Medical Molecular Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences(CAMS)&Peking Union Medical College100005 BeijingChina NHC Key Laboratory of Human Disease Comparative Medicine Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious DiseasesInstitute of Laboratory Animal ScienceCAMS and Comparative Medicine CenterPeking Union Medical CollegeBeijingChina Department of Pathology Institute of Basic Medical SciencesCAMS and Peking Union Medical CollegeBeijingChina Department of Biochemistry&Molecular Biology Tongji Medical CollegeHuazhong University of Science&Technology430030 WuhanChina

Dear Editor,Genetic variant Delta(B.1.617.2)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which possesses a remarkable ability to transmit and spread,is currently becoming predominant worldwide.Despite its great harm to human beings,how the Delta variant with T478K,P681R and L452R mutations achieves its ultrafast spread remains elusive.Entry of SARS-CoV-2 into host cells is mediated by a rapid enzymatic hydrolysis.

关键词： retention massive delta

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Effect of unburned carbon content in fly ash on the retention of 12 elements out of coal-combustion flue gas

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Journal of Environmental Sciences 2012年第9期24卷 1624-1629页

作者： Lucie Bartonov Bohumír ech Lucie Ruppenthalov Vendula Majvelderov Dagmar Juchelkov Zdeněk Klika Faculty of Metallurgy and Material Engineering VSB-Technical University of OstravaTr.17.listopadu 15708 33 Ostrava-PorubaCzech Republic

The aim of this study was to evaluate whether unburned carbon particles present in fly ash can help in the retention of S, Cl, Br, As, Se, Cu, Ni, Zn, Ga, Ge, Rb, and Pb out of flue gas during the coal combustion at fluidised-bed power station where the coal was combusted along with limestone. The competitive influence of 10%-25% CaO in fly ashes on the distribution of studied elements was studied as well to be clear which factor governs behaviour of studied elements. Except of S （with significant association with CaO） and Rb and Pb （with major affinity to A1203） the statistically significant and positive correlation coefficients were calculated for the relations between unburned carbon content and Br （0.959）, Cl （0.957）, Cu （0.916）, Se （0.898）, Ni （0.866）, As （0.861）, Zn （0.742）, Ge （0.717）, and Ga （0.588） content. The results suggest that the unburned carbon is promising material in terms of flue gas cleaning even if contained in highly calcareous fly ashes.

关键词： unburned carbon coal combustion fluidised bed trace elements emissions retention

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Effect of CaO on retention of S, Cl, Br, As, Mn, V, Cr, Ni, Cu, Zn,W and Pb in bottom ashes from fluidized-bed coal combustion power station

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Journal of Environmental Sciences 2014年第7期26卷 1429-1436页

作者： Lucie Bartonova Zdenek Klika Energy Units for Utilization of Non-Traditional Energy Sources Centre V?B-Technical University of Ostrava 708 33 Ostrava-Poruba Czech Republic Regional Material and Technology Research Centre VSB-Technical University of Ostrava 708 33 Ostrava-Poruba Czech Republic

This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with CaO content in bottom ashes were observed（for all four combustion tests） for S, As, Cl and Br（R = 0.917-0.999）. Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and CaO, so these elements showed association to materials other than Ca-bearing compounds（e.g., to aluminosilicates, organic matter, etc.）. Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically ＂not significant＂, i.e., these elements were not thought to be significantly associated with CaO. It was also discovered that major enrichment of CaO in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization.

关键词： Coal combustion Arsenic Chlorine Bromine CaO retention Fluidized-bed Trace elements

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retention and chiral recognition mechanism of organo-phosphorus compounds in high-performance liquid chromatography

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Science China Chemistry 2001年第2期44卷 147-153页

作者：黄君珉陈慧高如瑜王琴孙陈茹玉 Research Institute of Elemento-organic Chemistry Nankai University Tianjin China

In normal phase condition, a series of chiral phosphorus organic compounds have been separated by high-performance liquid chromatography. In order to study the retention and chiral recognition mechanism, the method of quantitative structure-enantioselectivity retention relationships (QSERRs) has been investigated from the quantitative equations established between the chromatographic retention of enantiomers and their molecular descriptors of physicochemical properties. The results show that on the Pirkle-type chiral stationary phase (CSP) of Sumichiral OA4700, it is the parameter of LUMO that gives the most contribution to the chromatographic re-tention of O-ethyl O-(substituted) phenyl N-isopropyl phosphoroamidothioates resulting from the interaction of hydrogen bond and (or) p-p interaction. Meanwhile, the chiral recognition is formed from the contribution of logP and LUMO.

关键词： high-performance liquid chromatography, chiral phosphorus organic compounds, chiral recognition mechanism, quantitative structure-enantioselectivity retention relationships.

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Sustaining health workforce recruitment and retention in township hospitals： a survey on 110 directors of township hospitals

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Frontiers of Medicine 2015年第2期9卷 239-250页

作者： Jingmin Zheng Jie Li Xingxing Jiang Bin Zhang Department of Social Medicine School of Public Health Chongqing Medical University Chongqing 400016 China Department of Health Policy Research School of Public Health Chongqing Medical University Chongqing 400016 China

Township hospitals, the main provider of rural primary healthcare in China, are severely understaffed. International studies on factors influencing rural working are increasing; however, studies on factors affecting the recruitment and retention of health workers in Chinese township hospitals are limited. The current study aims to understand the motivation of health workers and arrive at a systematic framework of pluralistic factors that would help support health workers in terms of receiving posts and remaining in posts in township hospitals. A three-stage integrated quantitative and qualitative methodology was employed. First, a survey on 120 directors of township hospitals was conducted to learn the latest status of health workers in township hospitals and distinguish existing problems. Second, after sending these problems back to the directors, an open-ended pen-and-paper survey was conducted to ask the directors to identify the factors influencing the attraction and retention of health workers in township hospitals. Third, four focus groups were conducted to gauge the underlying reasons. Five problems from the questionnaire survey were recognized, and numbers of thematic factors were identified at the individual, professional, and treatment environment from the pen-and-paper survey and focus group. Similar to other studies, this framing of both non-financial and financial elements affected the attraction and retention of health workers in township hospitals, thereby filling the gap in a Chinese context. Although several factors had been recognized earlier, our findings further highlighted the importance of these factors. Meanwhile, the factors identified in this study were barely explored in literature. This paper identifies and develops multi-faceted factors to call for a bundled package of multidimensional incentives if decision-makers get interested. The evidence-based findings in our study can be used to provide China-specific policy recommendations on how to recruit and retain health workers in rural ar

关键词： recruitment retention health workers township hospitals rural regions

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Whitefly feeding behavior and retention of a foregut-borne crinivirus exposed to artificial diets with different pH values

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Insect Science 2017年第6期24卷 1079-1091页

作者： Jaclyn S. Zhou Angel Y. S. Chen Martin Drucker Nicole H. Lopez Alyssa Carpenter James C. K. Ng Department of Plant Pathology and Microbiology and Center for Disease Vector Research University of California Riverside California USA INRA UMR BGPI Plant Pathogen Interactions Montpellier Cedex 5 France Barry University Miami Florida USA East Stroudsburg University E. Stroudsburg Pennsylvania USA

Transmission of plant viruses by phytophagous hemipteran insects encompasses complex interactions underlying a continuum of processes involved in virus acquisition, retention and inoculation combined with vector feeding behavior. Here, we investigated the effects of dietary pH on whitefly （Bemisia tabaci） feeding behavior and release of Lettuce infectious yellows virus （LIYV） virions retained in the vector＇s foregut. Electrical penetration graph analysis revealed that variables associated with whitefly probing and ingestion did not differ significantly in pH （4, 7.4, and 9） adjusted artificial diets. To investigate virus retention and release, whiteflies allowed to acquire LIYV virions in a pH 7.4 artificial diet were fed pH 4, 7.4, or 9 virion-free artificial （clearing） diets. Immunofluorescent localization analyses indicated that virions remained bound to the foreguts of approximately 20%-24% of vectors after they fed on each of the 3 pH- adjusted clearing diets. When RNA preparations from the clearing diets were analyzed by reverse transcription （RT） nested-PCR and, in some cases, real-time qPCR, successful amplification of LIYV-specific sequence was infrequent but consistently repeatable for the pH 7.4 diet but never observed for the pH 4 and 9 diets, suggesting a weak pH-dependent effect for virion release. Viruliferous vectors that fed on each of the 3 pH-adjusted clearing diets transmitted LIYV to virus-free plants. These results suggest that changes in pH values alone in artificial diet do not result in observable changes in whitefly feeding behaviors, an observation that marks a first in the feeding of artificial diet by whitefly vectors; and that there is a potential causal and contingent relationship between the pH in artificial diet and the release/inoculation of foregut bound virions.

关键词： Crinivirus dietary pH inoculation noncirculative semipersistent transmission retention whitefly

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