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The Effect of External Pressure on Mechanical Properties of Aquamarine Gemstone Using First Principles Studies

Journal of Minerals and Materials characterization and Engineering 2024年第5期12卷 237-246页

作者： Evarist Kahuluda Pulapa Ventkata Kanaka Rao stanley Mwanga Department of Physics College of Natural and Mathematical Sciences University of Dodoma Dodoma United Republic of Tanzania

Aquamarine gemstones are popular jewelry in the gemstone trade and are currently one of the important products in the world market because of their economic value. Aquamarine is a Beryllium Aluminium Silicate with the chemical formula Be3Al2Si6O18 and crystallizes in the hexagonal system with space group P6/mcc (192), and Tanzania has wide deposits of aquamarine gemstones. The quality of gemstone depends on its characteristic properties, including electronic, optical, and mechanical properties. In the present study, the effect of external pressure on mechanical properties including independent elastic constants and other related parameters such as Bulk modulus, Shear modulus, Young modulus, Poisson’s ratio, and compressibility were studied. Density Function Theory in the forcite module of the material studies software on the external pressure within the range of 0 - 200 GPa on the optimized structure at electrostatic, Van der Waals and Ewald terms were used in this study. The results reveal that the independent elastic constants are mechanically unstable at 50 - 120 Gpa and are stable at 0 - 40 GPa and above 120 GPa, with the average bulk modulus, shear modulus, young modulus, Poisson’s ratio of 2319.9447, 652.3058, 1789.2236, and 0.26 respectively with the compressibility of 0.059921/TPa, this indicates that aquamarine gemstones are stable against strain and strongly against shear stress but opposing shear deformation. These values are within other crystalline materials found in the literature. This provides technological backing for the comprehensive valuation of mechanical properties, quality, and stability of gemstones available in Tanzania.

关键词： Aquamarine Gemstones Mechanical Properties External Pressure Biovia Material Studio Forcite Module

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Fetal Urinary Obstruction and Intervention for Sacrococcygeal Teratoma:A case Report From Kenya

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Maternal-Fetal Medicine 2024年第3期6卷 196-200页

作者： Maryanne Muthoni Mwangi Sikolia Wanyonyi stanley Mugambi Department of Obstetrics and Gynaecology Aga Khan UniversityNairobi 30270-00100Kenya Department of pediatric Surgery Aga Khan UniversityNairobi 30270-00100Kenya

Fetal lower urinary tract obstruction is a rare condition commonly associatedwith significant perinatalmorbidity andmortality,particularly when detected in the second *** concurrent presentation of a recto-urethral fistula with membranous urethral atresia and sacrococcygeal teratoma has not been *** describe a case of extrinsic fetal lower urinary tract obstruction related to a recto-urethral fistula,diagnosed at 33 weeks gestation and managed by serial vesicocentesis until 38 *** case,notable for its absence of hypoplasia despite late diagnosis,resulted in a term delivery of a male *** delivery,pediatric surgeons performed an abdominal perineal resection of the *** vesicocentesis remains a viable management option for patients without access to intrauterine surgical interventions.

关键词： Lower urinary tract symptom Fetal lower urinary tract obstruction Vesicocentesis Sacrococcygeal teratoma Rectourinary fistula

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Microplastic pollution:An emerging contaminant in aquaculture

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Aquaculture and Fisheries 2023年第6期8卷 603-616页

作者： stanley iheanacho Miracle Ogbu Md Simul Bhuyan Johnny Ogunji Department of Fisheries and Aquaculture Alex Ekwueme Federal UniversityNdufu Alike Ebonyi StateAbakalikiP.M.B.1010Nigeri Department of Biology Alex Ekwueme Federal UniversityNdufu Alike Ebonyi StateAbakalikiP.M.B.1010Nigeria Bangladesh Oceanographic Research Institute Cox’s Bazar4730Bangladesh

Aquaculture largely contributes to aquatic products and consequential dietary protein for many ***,just like every other food sector,is faced with enormous challenges such as unfavorable climatic events,environmental stressors and ***(MP)are emerging contaminants in aquaculture following their perturbing occurrence in cultured fish,fishmeal and *** MPs pathways into aquaculture facilities include wastewater,pipe-borne water,dilapidated aquaculture facilities,fish gears,and aquafeed stuff(fishmeal).Techniques for the digestion,identification and characterization of MPs are critical to understanding their pathways,bioavailability and bioaccumulation patterns in aquaculture *** impacts of MPs on cultured fish species are identified as impaired growth,oxidative stress,neurotoxicity,reproductive toxicity,immunotoxicity,embryotoxicity,and *** of MPs in tissues and biological systems have been evidenced in several cultured *** efforts cum strategies such as upgrade of wastewater treatment facilities,screening of inlet pond water,screening of aquafeed stuff,regular maintenance and repair of culture facilities,could be effective to eradicate MP contamination in ***,regulatory policy on the use of plastics is key to mitigating the impact of MPs and ensure cleaner and sustainable aquaculture.

关键词： Microplastics Aquaculture Sources Impact Mitigation

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The Effects of Zinc Sulfate on the in Vitro Digestibility of Feeds in cervids

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Open Journal of Animal Sciences 2024年第3期14卷 157-167页

作者： Reese J. Thibodeaux Philip M. Urso stanley F. Kelley Marcy M. Beverly chris R. Stewart Ian c. Dunn Gentech Diagnostics Dallas Texas USA Department of Animal Science South Dakota State University Brookings South Dakota USA School of Agricultural Sciences Sam Houston State University Huntsville Texas USA 3-S Texas Outdoors/3-S Whitetails Bedias Texas USA

The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying cO2. Fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (cON). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADF, NDF, IVTD, or OM between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.

关键词： Zinc IVDMD In Vitro cervids

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Software and Mobile Apps as a Strategy for Productivity Improvement in the construction Industry

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Journal of Building construction and Planning Research 2024年第1期12卷 1-35页

作者： stanley Owuotey Bonney Jonas Ekow Yankah Kofi Owusu Adjei chris Kurbom Tieru Department of Built Environment University of Environment and Sustainable Development Somanya Ghana Department of construction Technology and Management Cape Coast Technical University Cape Coast Ghana Department of Building Technology Kumasi Technical University Kumasi Ghana

The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of these technology applications. The PRISMA principles utilised a scoping review methodology to ascertain pertinent studies and extract significant findings. From 2013 onwards, articles containing data on mobile applications or software designed to enhance productivity in the construction sector were obtained from multiple databases, including Emerald Insight, Science Direct, IEEE Xplore, and Google Scholar. After evaluating 2604 articles, 30 were determined to be pertinent to the study and were subsequently analysed for the review. The review identified five key themes: effectiveness, benefits, successful implementation examples, obstacles and limitations, and a comprehensive list of software and mobile apps. In addition, 71 software and mobile apps have shown potentially how these technologies can improve communication, collaboration, project management, real-time collaboration, document management, and on-the-go project information and estimating processes in the construction industry, increasing efficiency and productivity. The findings highlight the potential of these technologies such as Automation, Radio-Frequency Identification (RFID), Building Information Modeling (BIM), Augmented Reality (AR), Virtual Reality (VR), and Internet of Things (IoT) to improve efficiency and communication in the construction industry. Despite challenges such as cost, lack of awareness, resistance to change, compatibility concerns, human resources, technological and security concerns and licensing issues, the study identifies specific mobile applications and software with the potential to enhance efficiency significantly, improve productivity and streamline workflows. The broader societal impacts of construction software and mobile app development include increased effic

关键词： Software Mobile apps Productivity Technologies construction Industry

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有向动态网络的自发恢复（英文）

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Engineering 2024年第6期 208-214页

作者：刘雪明闫贤 H.Eugene stanley School of Artificial Intelligence and Automation & The MOE Engineering Research center of Autonomous Intelligent Unmanned Systems & the Key Laboratory of Image Processing Huazhong University of Science and Technology center for Polymer Studies Department of Physics Boston University

complex networked systems, which range from biological systems in the natural world to infrastructure systems in the human-made world, can exhibit spontaneous recovery after a failure; for example, a brain may spontaneously return to normal after a seizure, and traffic flow can become smooth again after a jam. Previous studies on the spontaneous recovery of dynamical networks have been limited to undirected networks. However, most real-world networks are directed. To fill this gap, we build a model in which nodes may alternately fail and recover, and we develop a theoretical tool to analyze the recovery properties of directed dynamical networks. We find that the tool can accurately predict the final fraction of active nodes, and the prediction accuracy decreases as the fraction of bidirectional links in the network increases, which emphasizes the importance of directionality in network dynamics. Due to different initial states, directed dynamical networks may show alternative stable states under the same control parameter, exhibiting hysteresis behavior. In addition, for networks with finite sizes, the fraction of active nodes may jump back and forth between high and low states, mimicking repetitive failure-recovery processes. These findings could help clarify the system recovery mechanism and enable better design of networked systems with high resilience.

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Agronomic Performance, Stability Analysis and Evaluation of Anthracnose Disease Resistance of common Bean Lines Derived by Marker-Assisted Backcrossing in Uganda

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Agricultural Sciences 2024年第3期15卷 376-397页

作者： stanley T. Nkalubo Annet Namayanja Annet Namusoke Jane Mukabaranga Nampijja Shakirah Allan Nkuboye Paul Gepts Wakjira Tesfahun Jebesa National crops Resources Research Institute (NacRRI) Namulonge Kampala Uganda Department of Plant Sciences/MS1 University of California Davis CA USA Department of Plant Science and Horticulture College of Agriculture and Veterinary Medicine Jimma University Jimma Ethiopia

The present study focused on evaluating the agronomic performance, stability, and anthracnose resistance of common bean lines derived through Marker-Assisted Backcrossing in Uganda. Eight marker-assisted selection (MAS) backcross-derived bush bean lines with red seed types, alongside two checks, were evaluated in a randomized complete block design replicated two times in five locations for three consecutive crop-growing seasons in 2021 and 2022. The study aimed to identify lines with both high stable yields and enhanced resistance to anthracnose disease for potential release and utilization in future bean varietal development in Uganda. Agronomic traits, including days to 50% flowering, days to 90% physiological maturity, seed yield, seed yield components, and anthracnose disease reaction under natural infestation were assessed. The response to anthracnose disease was further assessed using six isolates of colletotrichum lindemuthianum representing six different races. Results indicated that the agronomic performances of the MAS backcross-derived bush bean lines were statistically comparable to the recurrent parent NABE14. Specifically, six lines exhibited statistically equal to or higher performance than NABE14 in terms of seed yield, total number of seeds and number of pods per plant. The combined analysis of variance for seed yield showed significant (p co-42 and co-5 anthracnose resistance genes in the derived line. In conclusion, UGKT-B157-4, identified as the best-performing and stable genotype, demonstrates promise for release and use in future bean varietal development in Uganda, offering a combination of high yields and enhanced anthracnose disease resistance. The study provides valuable insights into the potential of Marker-Assisted Backcrossing in improving common bean varieties in the region.

关键词： colletotrichum lindemuthianum Genotype by Environment Interaction GGE Biplot MAS

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去埃及旅游被骗到裸奔？这样的文明古国，你还敢去吗？

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环球人文地理 2024年第13期 44-53页

作者：史英静陈曦stanley 纯纯 Sofiia Alexey Fedorenko olyasolodenko 摄图网

比起金字塔攻略，你更需要的是一份防骗指南。“在埃及，我只允许自己被骗3次。”互联网上一篇名为《第一批去埃及旅行的人，已经被骗到快裸奔了》的文章引起了无数网友共鸣，去过埃及的游客们纷纷留言，吐槽自己的被骗经历，没去过的...

比起金字塔攻略，你更需要的是一份防骗指南。“在埃及，我只允许自己被骗3次。”互联网上一篇名为《第一批去埃及旅行的人，已经被骗到快裸奔了》的文章引起了无数网友共鸣，去过埃及的游客们纷纷留言，吐槽自己的被骗经历，没去过的人，则是连发几声不可思议的感叹。旅游，埃及的支柱产业提到埃及，即使没去过的人也能说出几个关键词：尼罗河、狮身人面像、金字塔、木乃伊……这些自然景观与人文景点吸引着世界各地的游客，也为埃及提供着源源不断的财政收入。

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失落的佩特拉是什么让比肩罗马的文明一夜瓦解？

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环球人文地理 2024年第17期 26-35页

作者： Sara 陈曦stanley 秋也流浪记健忘的行摄世界 unsplash 约旦旅游局

这是一座建立在沙漠中的城市，引洪水灌溉出一片绿洲;这是一处失落的文明，曾经诞生了超越雅典、比肩罗马的帝国;这是一朵岩石打造的玫瑰，洪水杀不死，又在黄沙中重现……在约旦哈西姆王国南部的峡谷中，有一座神秘的城市——佩特拉。...

这是一座建立在沙漠中的城市，引洪水灌溉出一片绿洲;这是一处失落的文明，曾经诞生了超越雅典、比肩罗马的帝国;这是一朵岩石打造的玫瑰，洪水杀不死，又在黄沙中重现……在约旦哈西姆王国南部的峡谷中，有一座神秘的城市——佩特拉。它被诗人伯根赞颂为“一道举世无双的东方奇观，一座与时间并驾齐驱的玫瑰古城”。

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渴！渴！渴！墨西哥城即将用光最后一滴水！

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环球人文地理 2024年第11期 46-55页

作者：方小白陈曦stanley ulrikestein 欧德立 Alex Wolf Leonardo fforriol

2024年春夏之交，“干渴的墨西哥城”频繁作为主角，登上其他国家的新闻：“约2100万居民面临缺水”“零日即将到来！或用光最后一滴水”“谁来给墨西哥城解渴”……电视上接受采访的墨城居民无不忧心忡忡。或许他们并不知道，此时此刻...

2024年春夏之交，“干渴的墨西哥城”频繁作为主角，登上其他国家的新闻：“约2100万居民面临缺水”“零日即将到来！或用光最后一滴水”“谁来给墨西哥城解渴”……电视上接受采访的墨城居民无不忧心忡忡。或许他们并不知道，此时此刻整个城市如此缺水，跟他们祖先之间的一场战争有关，也跟一场“杀湖案”有关—为了扩大居住面积，墨城人花几百年时间排光了一个巨湖的水，“杀死”了湖，利用湖底平整的土地建起了伟大的墨西哥城。

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