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Management of Significant Environmental Aspects and Impacts in Accordance with the ISO 14001:2015 Standard during the Operation and Maintenance Phase of Senegal River Basin Development Authority Hydroelectric Works and Facilities: The Case of Manantali Dam
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期89-110,共22页
This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version ... This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version 2015 standard. To do this, the mapping of the different work areas made it possible to identify all the activities within the framework of the farm. Based on the mapping, environmental measurements made including noise level, brightness, electric and magnetic fields, total particles, PM10, PM2.5, PM1 showed the work areas with the exposure limit values exceeded. The inventories of the waste produced show eighteen (18) types of waste, 67% of which are special industrial waste (SIW), 28% are ordinary industrial waste (OIW) and 5% are inert industrial waste (IIW). The identification and assessment of environmental aspects and impacts made it possible to determine sixteen (16) positive and negative significant environmental aspects (ESAs). The positive AES must be maintained, and for the negative ones, mitigation and mitigation measures must be put in place in order to manage them effectively. This will ultimately improve environmental management in the operation of hydroelectric structures and facilities. 展开更多
关键词 Manantali Environmental aspect Environmental Impact Waste Mitigation and Mitigation Measures
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Psychosocial Aspects of Male Infertility at the Service of Urology-Andrology of the Hospital of the Sino-Guinean Friendship
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作者 Alimou Diallo Thierno Oumar Diallo +3 位作者 Alpha Oumar Barry Ibrahima Bah Abdoulaye Bobo Diallo Oumar Raphiou Bah 《Open Journal of Urology》 2024年第7期400-406,共7页
Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The ... Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The study covered 17 patients, all received for a desire to conceive after at least one year of regular sexual intercourse without contraception. The data were collected from patient interviews using a pre-established questionnaire. Results: The average age of the patients was 32.07 years with extremes of 23 years and 42 years. During this study, 64.70% of patients were no longer participating in community ceremonies. The patients’ relationships with their spouse and family deteriorated in 52.94% and 47.06%, respectively. Conversely, relations with the family of origin remained unchanged in 70.59 percent of cases. The reduction in economic activity was by 13 patients (76.48%). Conclusion: Male infertility causes a real psychic earthquake in men with its corollaries of negative feelings. The rather complex moral repercussions of male infertility affect not only the individual, his/her partner, and family, but also economic activity. 展开更多
关键词 Male Infertility Psycho-Social aspect Psychic Earthquake
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Study on the Influence of Aspect Ratio on the Seismic Response and Overturning Resistance of a New Staggered Story Isolated Structure
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作者 Tiange Zhao Dewen Liu 《World Journal of Engineering and Technology》 2024年第3期617-634,共18页
The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stif... The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases. 展开更多
关键词 aspect Ratio A New Staggered Story Isolated Structure Seismic Response Overturning Resistance Ratio Isolated Bearing
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Response of soil nutrients to terracing and environmental factors in the Loess Plateau of China
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作者 Die Chen Wei Wei +2 位作者 Liding Chen Bojun Ma Hao Li 《Geography and Sustainability》 CSCD 2024年第2期230-240,共11页
Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in... Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in landscapes prone to drought.They are influenced by factors such as land-use type,slope aspect,and altitude.In this study,we sought to examine the impact of terracing on soil nutrients(soil organic content(SOC),total nitrogen(TN),nitrate-nitrogen(NO_(3)^(-)-N),ammonium nitrogen(NH_(4)^(+)-N),total phosphorus(TP),available phosphorus(AP),total potassium(TK),and available potassium(AK))and how they vary with environmental factors in the Chinese Loess Plateau.During the growing season,we collected 540 soil samples from the 0 to 100 cm soil layer across five major land-use types,different slope aspects,and varying altitudes.Additionally,a meta-analysis of literature data further corroborated the effective accumulation of soil nutrients through terracing in the Loess Plateau.Our findings are as follows:(1)Terraced fields,regardless of land-use type,showed a significant improvement in SOC and TN content.(2)Soil nutrient contents within terraced fields were predominantly higher on sunny slopes.(3)Terraces at lower altitudes are characterized by elevated SOC concentrations.(4)A meta-analysis of literature data pertaining to terracing and soil nutrients in this region confirmed the effective accumulation of soil nutri-ents through terracing.The elucidated outcomes of this study offer a profound theoretical underpinning for the accurate planning and management of terraces,the scientific utilization of land resources,and the enhancement of land productivity. 展开更多
关键词 TERRACE Soil nutrients Land-use Slope aspect ALTITUDE Loess Plateau
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Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface
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作者 Zhiwei Li Jianfu Zhang +3 位作者 Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期449-467,共19页
High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effect... High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing techniques.This study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect ratio.Unlike conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving tool.The tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material deformation.Thanks to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling off.Since one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of EV-chiseling.Next,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process parameters.Then,surface texturing tests are performed on copper to verify the efficacy of EV-chiseling.Uniformed micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on copper.Compared with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 times.The experimental results also verify the accuracy of the developed surface generation model of microstructures.Finally,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed. 展开更多
关键词 metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation
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Effect of Low pH on Forming Process of Desulfurization Gypsum Composite Boards Strengthened by Melamine-formaldehyde Resin
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作者 CAO Lijiu ZHANG Jiyao +4 位作者 WANG Xinqi ZHANG Xinhe HUANG Jian CHEN Yufang JIN Tao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1223-1228,共6页
Through exploring the effects of low pH on the composite system of desulfurization gypsum(DG)enhanced by melamine-formaldehyde resin(MF),it is found that the inducing of sulfate-ion,in contrast to chloride and oxalate... Through exploring the effects of low pH on the composite system of desulfurization gypsum(DG)enhanced by melamine-formaldehyde resin(MF),it is found that the inducing of sulfate-ion,in contrast to chloride and oxalate ions,favors the longitudinal growth of the crystalline form of the hydration product,which was relatively simple and had the highest length to width(L/D)ratio.At the same time,MF can also improve L/D ratio of gypsum hydration products,which favors the formation of hydrated whiskers.Finally,in a composite system composed of hemihydrate gypsum,MF,and glass fibers,when dilute sulfuric acid was used to regulate pH=3-4,the tight binding formed among the components of the composite system compared to pH=5-6.The hydration product of gypsum adheres tightly to glass fiber surface and produces a good cross-linking and binding effect with MF.The flexural strength,compressive strength,elastic modulus,and water absorption of the desulphurized gypsum composite board is 22.7 MPa,39.8 MPa,5608 MPa,and 1.8%,respectively. 展开更多
关键词 MF-reinforced desulphurized gypsum board composite forming system low pH condition hydration process aspect ratio synergistic effect
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Influence of quarantine during the coronavirus disease 2019(COVID-19)pandemic on physical and psychosocial aspects:perceptions of 214 Brazilian athletes
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作者 Eliane de Morais Machado Leonardo Luiz Barretti Secchi +1 位作者 Paula Rezende Camargo Luciana De Michelis Mendonca 《Global Health Journal》 2023年第1期49-54,共6页
Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their ph... Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their physical and psychosocial aspects,sleep quality and coping strategies during the quarantine of the coronavirus disease 2019(COVID-19)pandemic.Methods:This was a cross-sectional study with online survey,performed with Brazilian athletes(amateur and professional)over 18 years.The main outcomes measures assessed were physical and psychosocial aspects,sleep quality and coping strategies.Results:A total of 214 athletes were included.The average weekly hours of training during the quarantine was 4.71±3.71 h,of which 64.5%athletes(138/214)were oriented by medical staff during training.For 52.8%(113/214)of athletes,training intensity during the quarantine was different/very different from the intensity before the quarantine.79.4%athletes(170/214)reported moderate to extreme difficulties in keeping the same level of training during the quarantine.77.1%athletes(165/214)had moderate to extreme anxiety and each of the athletes had concern about his or her athletic career future,including return to the sport.72.9%athletes(156/214)reported change in sleep schedule during the quarantine period.Conclusion:The quarantine period during COVID-19 pandemic negatively affected the athlete^perception about training routine,since athletes reported reduction in training hours and training intensity.Overall,the athletes reported that they were moderately to extremely anxious.They also had concerns about their career in the future,as well as concerns regarding return to sport. 展开更多
关键词 Social isolation Performance Psychological aspects Sleep quality Sport
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Sustainability as an Ethical Aspect of the Theory-Practice Gap in Business Schools
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作者 Guoxin Ma 《Journal of Sustainable Business and Economics》 2023年第2期25-36,共12页
This paper aims to reframe sustainability as an ethical aspect of the theory-practice gap in business and management education for sustainable development,which should be viewed as an integral part of knowledge produc... This paper aims to reframe sustainability as an ethical aspect of the theory-practice gap in business and management education for sustainable development,which should be viewed as an integral part of knowledge produced and disseminated in business schools.The paper adopts a narrative approach to review the relevant literature on two streams of research,namely,the theory-practice gap and sustainability in reforming business schools.The synthesis and discussion of the existing literature suggest that while sustainability is frequently viewed with an ethical sentiment,the existing research overlooks its significance in bringing together knowledge and practice in business schools.This paper highlights the potential of sustainability as a theoretical lens in bridging the theory-practice gap in business schools;proposing to rethink the conceptual space that lies in ethics for further theoretical developments.The author urges business and management scholars to engage in burgeoning debates on business school reforms relating to the theory-practice gap and sustainability with an emphasis on ethics.The author contends that the neglected theoretical linkages between the theory-practice gap and sustainability provide fruitful directions for future research.Through a moral lens,business schools can move toward responsible management education for a more sustainable future. 展开更多
关键词 Management education Business school SUSTAINABILITY theory-practice gap Moral education Ethical aspect of knowledge REFORM
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The Synthesis of Aspects on the Management of Second Language Teaching
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作者 李阳 李晓理 《语言与文化研究》 2009年第1期11-16,共6页
Principles which teachers should adhere to in second language class are based on the synthesis of linguistic,cultural and competent aspects.This paper first puts forward linguistic,cultural and competent aspects of se... Principles which teachers should adhere to in second language class are based on the synthesis of linguistic,cultural and competent aspects.This paper first puts forward linguistic,cultural and competent aspects of second language teaching.Then,the principles which teachers should adhere to in second language class are introduced.Finally,the synthesis implication for second language teaching is presented. 展开更多
关键词 LINGUISTIC CULTURAL and COMPETENT aspectS SECOND l
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A Misleading Aspect in The Use of English Teaching Language and Its Countermeasures
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作者 陈金 杨克力 《中国校外教育(上旬)》 2008年第S1期368-368,367,共2页
Teacher plays a key role in language teaching.Teaching language is the first thing that students notice of their English teacher's English.However,there is a misleading aspect in the use of teaching language.The a... Teacher plays a key role in language teaching.Teaching language is the first thing that students notice of their English teacher's English.However,there is a misleading aspect in the use of teaching language.The author picks it out and offers some possible solutions. 展开更多
关键词 MISLEADING aspect English TEACHING LANGUAGE Counte
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Shales in the Qiongzhusi and Wufeng–Longmaxi Formations:a rock-physics model and analysis of the effective pore aspect ratio 被引量:4
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作者 杨志强 何涛 邹长春 《Applied Geophysics》 SCIE CSCD 2017年第3期325-336,459,共13页
The shales of the Qiongzhusi Formation and Wufeng-Longmaxi Formations at Sichuan Basin and surrounding areas are presently the most important stratigraphic horizons for shale gas exploration and development in China. ... The shales of the Qiongzhusi Formation and Wufeng-Longmaxi Formations at Sichuan Basin and surrounding areas are presently the most important stratigraphic horizons for shale gas exploration and development in China. However, the regional characteristics of the seismic elastic properties need to be better determined. The ultrasonic velocities of shale samples were measured under dry conditions and the relations between elastic properties and petrology were systemically analyzed. The results suggest that 1) the effective porosity is positively correlated with clay content but negatively correlated with brittle minerals, 2) the dry shale matrix consists of clays, quartz, feldspars, and carbonates, and 3) organic matter and pyrite are in the pore spaces, weakly coupled with the shale matrix. Thus, by assuming that all connected pores are only present in the clay minerals and using the Gassmann substitution method to calculate the elastic effect of organic matter and pyrite in the pores, a relatively simple rock-physics model was constructed by combining the self-consistent approximation (SCA), the differential effective medium (DEM), and Gassmann's equation. In addition, the effective pore aspect ratio was adopted from the sample averages or estimated from the carbonate content. The proposed model was used to predict the P-wave velocities and generally matched the ultrasonic measurements very well. 展开更多
关键词 Qiongzhusi Wufeng-Longmaxi SHALE pore aspect ratio Gassman equation
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The Aspectual Marker-le in Mandarin Chinese——A Syntactic Approach under the Framework of MP 被引量:1
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作者 赵瑾 《科技信息》 2008年第29期222-223,235,共3页
时体范畴在现代语言学研究中占有重要地位。由于汉语属于孤立性语言,缺乏词形的曲折变化,因此汉语中的时体研究备受语言学家的关注。本文在乔姆斯基(1995)的最简方案理论指导下,运用特征核查理论,探讨了普通话中"了"这个体标... 时体范畴在现代语言学研究中占有重要地位。由于汉语属于孤立性语言,缺乏词形的曲折变化,因此汉语中的时体研究备受语言学家的关注。本文在乔姆斯基(1995)的最简方案理论指导下,运用特征核查理论,探讨了普通话中"了"这个体标记的句法地位以及它们的句法表现。本文得出结论:汉语中的体标记"了"在最简方案的特征核查理论下可以得到充分的解释。这有力支持了普遍语法中追求解释充分性的科学性,并向构建普遍语法的目标又迈进了一步。 展开更多
关键词 体标记 最简方案 特征核查理论 一致关系 语言学
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Critical Success Factors Influencing the Implementation of Sustainable Energy System in Uganda: A Case of Inter-University Council of East Africa Energy Project at the Head Quarters in Kampala, Uganda
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作者 Kiplangat Richard Koskei Peter Musau Cyrus Wekesa 《Energy and Power Engineering》 2023年第12期482-499,共18页
The widespread usage of clean and sustainable energy sources is leading to a significant transformation of the world’s energy systems. Over-reliance on only the national grid energy system has made institutions fail ... The widespread usage of clean and sustainable energy sources is leading to a significant transformation of the world’s energy systems. Over-reliance on only the national grid energy system has made institutions fail to sustain energy systems. The council is only connected to the national grid electricity supply system, with diesel generators as the only alternative, which is unhealthy and unsafe. Surprisingly, even with such alternatives, power shortages have persisted despite government efforts to provide a solution to the shortages by installing numerous off-grid systems. Due to such a situation, the council would construct a sustainable energy system as a remedy. Thus, the purpose of this study was to establish critical success factors influencing the implementation of a sustainable energy system at the Inter-University Council of East Africa (IUCEA) Head Quarters, Kampala-Uganda. A cross-sectional survey design was used;a sample size of 84 participants was selected. Questionnaire survey and interview methods were utilized. The study found that the most significant (p < 0.05) critical factors in the implementation of sustainable energy in institutions are;the use of innovative technologies and infrastructure, the use of efficient zero emissions for heating and cooling, integration of renewable energy use in the existing buildings, building and renovating in an energy-efficient way, integrating regional energy systems, improving energy efficiency in the buildings, enhanced zero emission power technologies, energy efficient equipment in place and stakeholder empowerment in energy management. This study concludes that institutions like;the Inter-University Council of East Africa (IUCEA) need to clearly state policies and actions of energy management. The roles and responsibilities of each member have to be clearly stated while capturing the activities involved in energy conservation, energy security and energy efficiency. 展开更多
关键词 Precarious aspects EXECUTION Viable Energy Arrangement Inter-University Council Energy Effectiveness Energy Safety and Energy Management
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Morphological, physiological and molecular characteristics of the seedless 'Hongjiangcheng' sweet orange
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作者 Pei Yin Wenyu Ding +4 位作者 Haipeng Zhang Xiao Liu Hongyan Zhang Jiwu Zeng Juan Xu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期437-449,共13页
Seedless citrus has become one of the breeding goals due to its high edible ratio and convenience in fresh consumption and processing.In this study, the ‘Hongjiangcheng' sweet orange(WT) and its seedless mutant(M... Seedless citrus has become one of the breeding goals due to its high edible ratio and convenience in fresh consumption and processing.In this study, the ‘Hongjiangcheng' sweet orange(WT) and its seedless mutant(MT) after cobalt-60 radiation were selected to study the formation metabolism of citrus seedless phenotype. Compared with WT, the MT had altered primary metabolite contents, as indicated by GC-MS analysis. The mature pollen of the MT was mostly distorted and shrunken, and the orange mutant exhibited significantly lower fertility than the WT. Through pollination experiments and paraffin sectioning of the MT, we observed self-compatibility during pollen tube germination in situ, in combination with the absence of natural parthenocarpy and arrested zygotic embryo development at the fourth week after pollination. From transcriptomic analyses of ovules in the fourth week, 815 differentially expressed genes(DEGs) were identified.Furthermore, according to the annotation of gene function and qRT-PCR analysis, Cs4g10930, Cs5g21900 and orange1.1t02243 were identified as candidate genes that may govern the mechanism of seedlessness. Finally, Agrobacterium-mediated transformation verified that the overexpression of Cs4g10930 and Cs5g21900 in Newhall navel orange calli inhibited embryoid production. This study provides a better understanding of seedless formation in citrus and two key genes that may play an important role in the early selection of seedless lines in citrus breeding programs. 展开更多
关键词 Citrus sinensis Seed abortion Transcriptomic sequencing Morphological aspects Candidate genes
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Biermer’s Disease at the Donka National Hospital in Guinea—Epidemio-Clinical, Therapeutic and Evolutionary Aspect in the Internal Medicine Department
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作者 Thierno Amadou Wann Mamadou Sarifou Diallo +6 位作者 Djenabou Diallo Kadiatou Diallo Mamadou Lamine Yaya Bah Mamadou Diakhaby Mohamed Cissoko Amadou Kaké Djibril Sylla 《Open Journal of Internal Medicine》 2023年第3期218-224,共7页
Introduction: Biermer’s disease is an autoimmune disease characterized by a lack of absorption of vitamin B12 in connection with the production of antibodies (A) destroying the intrinsic factor (IF) which allows the ... Introduction: Biermer’s disease is an autoimmune disease characterized by a lack of absorption of vitamin B12 in connection with the production of antibodies (A) destroying the intrinsic factor (IF) which allows the absorption of vitamin B12 (cobalamin). These clinical manifestations are polymorphic and severe in our context. The objective of this work is to identify the epidemiological-clinical, therapeutic and evolutionary characteristics of Biermer’s disease in Guinean population. Materials and methods: This was a retrospective of patient files followed for Biermer’s disease at the internal medicine department of Donka National Hospital from January 2012 to December 2021. Results: Eight patients were included including 5 women and 3 men. The average age of the patients was 48 years old. The diagnostic delay was 3.6 years on average. All our patients had bioclinical anemia (8 cases, i.e. 100%) followed by epigastralgia in 4 cases (50%), neurological damage such as sensitive polyneuropathy in 3 cases (37.5%). Four patients had acquired melanoderma (50%). Hypovitaminosis B12 was found in 4 patients. The myelogram performed in three patients (37.5%) found medullary megaloblastosis. One patient had Hashimoto’s disease associated with Biermer’s disease in endoscopy, (FOGD) found fundica trophy on macroscopy in 4 cases (50%). Treatment consisted of B12 vitamin therapy in all cases with a favorable clinical and biological outcome. Conclusion: Biermer’s disease remains common in Africa and is characterized at a younger age in addition to the severity of clinical and biological manifestations. The care consists of taking vitamin B12 which remains accessible in our context. 展开更多
关键词 Biermer’s Disease Donka aspects Epidemiological-Clinical theRAPEUTICS
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Evaluation of Different Topographic Parameters Extracted from the Digital Elevation Measurements with the Use of Geostatistical Interpolation Methods
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作者 Fahmy F. F. Asal 《International Journal of Geosciences》 2023年第12期1226-1242,共17页
Gradient slope, aspect slope, profiling and contourlines are important topographic parameters that can be derived from digital elevation data obtained from different sources with exploitation of different interpolatio... Gradient slope, aspect slope, profiling and contourlines are important topographic parameters that can be derived from digital elevation data obtained from different sources with exploitation of different interpolation techniques. Geostatistical interpolation methods such as ordinary kriging models constitute reliable alternatives to deterministic approaches in creation of continuous surface models from discrete elevation data. This research aimed at extraction, analysis, and evaluation of different terrain parameters elevation measurements with the use of different ordinary kriging models including the linear model, the circular model, the spherical model, the exponential models, and the Gaussian model. Different ordinary kriging models under ESRI ArcView 3.3 package along with its 3D analyst and Spatial analysis extensions have been exploited in extraction of gradient slope maps, aspect slope maps, and hillshade maps in addition to contourline maps from a sample of elevation data. Visual analysis of the gradient slope maps shows great similarities between the slope maps from the linear, circular, spherical, and exponential OK models, however, that from OK Gaussian models look very different as different sizes and arrangements of the colour patches, referring to different tones and different textures where smooth tones and smooth textures dominate the gradient slope map from the OK Gaussian model. Thus, gradient slope degradation and smoothing are considerably high in the gradient slope map from Gaussian model compared to the slope maps from the other four OK models. Also, the mean slope in the Gaussian model records the lowest value with the lowest value of the standard deviation of slopes in the same map reflecting less structured and highly smoothed gradient slope map compared to the slope maps from the other OK models. Thus, similar sizes of the colour patches and similar tones and similar texture dominate the different aspect slope maps. This is not the case in Figure 2(e) which depicts the aspect slope map extracted with the use of the Gaussian OK model where the smooth colour patches, smooth tones and smooth textures can be observed. Also, the Aspect map, hillshade map and the contourline map from Gaussian OK model are visually and statistically different from their corresponding maps created with the other four OK models. Finally, analysis of extracted two groups of profiles shows that the profiles extracted with the use of linear, circular, spherical, and exponential OK models run close and show highly corrugated and varied terrain. This is different from the profiles with the use of the Gaussian model which are less corrugated and tend to smooth and approximate different parts of the terrains. 展开更多
关键词 Topographic Parameters Gradient Slope aspect Slope Shaded Relief Contourline PRofILING Ordinary Kriging Models
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Psychological and social aspects of infertility in men: an overview of the evidence and implications for psychologically informed clinical care and future research 被引量:20
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作者 Jane RW Fisher Karin Hammarberg 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第1期121-129,179,共10页
Research concerning the psychosocial aspects of infertility and infertility treatment focuses more often on women than men. The aim of this review was to synthesize the English-language evidence related to the psychol... Research concerning the psychosocial aspects of infertility and infertility treatment focuses more often on women than men. The aim of this review was to synthesize the English-language evidence related to the psychological and social aspects of infertility in men and discuss the implications of these reports for clinical care and future research. A structured search identified 73 studies that reported data concerning the desire for fatherhood and the psychological and social aspects of diagnosis, assisted reproductive technology (ART) treatment and unsuccessful treatment among men with fertility difficulties. The studies are diverse in conceptualisation, design, setting and data collection, but the findings were reasonably consistent. These studies indicated that fertile and infertile childless men of reproductive age have desires to experience parenthood that are similar to those of their female counterparts; in addition, diagnosis and initiation of treatment are associated with elevated infertility-specific anxiety, and unsuccessful treatment can lead to a state of lasting sadness. However, rates of clinically significant mental health problems among this patient population are no higher than in the general population. Infertile men who are socially isolated, have an avoidant coping style and appraise stressful events as overwhelming, are more vulnerable to severe anxiety than men without these characteristics. Men prefer oral to written treatment information and prefer to receive emotional support from infertility clinicians rather than from mental health professionals, self-help support groups or friends. Nevertheless, structured, facilitated psycho-educational groups that are didactic but permit informal sharing of experiences might be beneficial. There are gaps in knowledge about factors governing seeking, persisting with and deciding to cease treatment; experiences of invasive procedures; parenting after assisted conception; adoption and infertility-related grief and shame among men. Few resource-constrained countries have any data concerning male experiences of infertility. 展开更多
关键词 assisted reproductive technologies male infertility psychologically-informed clinical care psychosocial aspects
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Influence of topographic aspect on floristic diversity, structure and treeline of afromontane cloud forests in the Bale Mountains,Ethiopia 被引量:4
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作者 Eshetu Yirdaw Mike Starr +1 位作者 Mesele Negash Fantaw Yimer 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期919-931,共13页
We studied the influence of east and west aspects on floristic composition, diversity, structure and treeline of afromontane cloud forests at Rira in the Bale Mountains, southeast Ethiopia. In addition, we studied how... We studied the influence of east and west aspects on floristic composition, diversity, structure and treeline of afromontane cloud forests at Rira in the Bale Mountains, southeast Ethiopia. In addition, we studied how aspect relates to and/or interacts with other topographic and edaphic factors in influencing vegetation diversity. Strati- fied systematic plot sampling was used to survey the floristic composition, diversity and structure of forests on east- and west-facing slopes. The sample plot size was 20 x 20 m and a total of 36 plots were inventoried. A total of 72 composite soil samples were collected and analysed. Woody species richness of the forest on the east-facing slope was 1.7 times higher than on the west-facing slope. Shannon, Simpson and Log-series alpha diversity indices and evenness of forests on the east-facing slope were sig- nificantly higher than on the west-facing slope. NMDS ordination indicated that the east- and west-facing slopes formed two clusters of species and aspect explained 55.2 % and 10.4 % of the variation in species richness and abun- dance, respectively. There was no significant difference between aspects in stand structure except in dominantheight, which was higher on the east-facing slopes. There was significant interaction between aspect and elevation in influencing woody species diversity. The four plant com- munity groups, which were identified using cluster and indicator species analysis were represented differently on the east and west aspects. The treeline on the east-facing slope (3352 m) was located about 110 m higher than on the west-facing slope (3240 m). Soil moisture deficiency was unlikely to be a limiting factor on either site. Near the equator, east-west aspect was shown to have considerable impact on floristic composition, diversity, structure, and treeline position of montane forests. Diurnal cloud move- ment patterns and its impact on microclimate of slope aspect should be taken into account in future studies of cloud forest diversity, structure, and treeline position. 展开更多
关键词 AFROMONTANE aspect Cloud forests Ethiopia Floristic diversity
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Optimization of process parameters of the activated tungsten inert gas welding for aspect ratio of UNS S32205 duplex stainless steel welds 被引量:5
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作者 G.MAGUDEESWARAN Sreehari R.NAIR +1 位作者 L.SUNDAR N.HARIKANNAN 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第3期251-260,共10页
The activated TIG(ATIG) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much attention.The shape of a weld in terms of its width-to-d... The activated TIG(ATIG) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much attention.The shape of a weld in terms of its width-to-depth ratio known as aspect ratio has a marked influence on its solidification cracking tendency.The major influencing ATIG welding parameters,such as electrode gap,travel speed,current and voltage,that aid in controlling the aspect ratio of DSS joints,must be optimized to obtain desirable aspect ratio for DSS joints.Hence in this study,the above parameters of ATIG welding for aspect ratio of ASTM/UNS S32205 DSS welds are optimized by using Taguchi orthogonal array(OA)experimental design and other statistical tools such as Analysis of Variance(ANOVA) and Pooled ANOVA techniques.The optimum process parameters are found to be 1 mm electrode gap,130 mm/min travel speed,140 A current and 12 V voltage.The aspect ratio and the ferrite content for the DSS joints fabricated using the optimized ATIG parameters are found to be well within the acceptable range and there is no macroscopically evident solidification cracking. 展开更多
关键词 DUPLEX STAINLESS steel ATIG WELDING aspect ratio Taguchi design FERRITE number Solidification cracking
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Optimizing the Aspect Ratio of Cephalexin in Reactive Crystallization by Controlling Supersaturation and Seeding Policy 被引量:3
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作者 Mingchen Li Zeren Shang Baohong Hou 《Transactions of Tianjin University》 EI CAS 2019年第4期348-356,共9页
Batch crystallization in acidic aqueous solution of cephalexin was conducted by reactive crystallization with or without seeding. Supersaturation was generated by mixing ammonia and acidic aqueous solution of cephalex... Batch crystallization in acidic aqueous solution of cephalexin was conducted by reactive crystallization with or without seeding. Supersaturation was generated by mixing ammonia and acidic aqueous solution of cephalexin and controlled by solution feeding rate and seeding conditions. UV and Morphologi G3 were used to measure supersaturation and aspect ratio. Experimental results demonstrated that burst nucleation occurred and the products were needle-like at high supersaturation;meanwhile, the products were plate-like and had high aspect ratio at low supersaturation. Analysis of the measured supersaturation profi les and corresponding aspect ratio explained the mechanisms governing the aspect ratio. The optimized operating parameters were also proposed (seeding supersaturation is equal to 1.3, seed mass ratio 8% and feeding rate 368 μL/min). 展开更多
关键词 Reactive CRYSTALLIZATION SUPERSATURATION control aspect ratio Crystal HABIT
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