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Population dynamics of the tropical oyster Magallana bilineata(Mollusca,Bivalvia,Ostreidae)in Mengkabong Bay,Tuaran,Malaysia

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Aquaculture and Fisheries 2024年第2期9卷 295-305页

作者： Joanna w.Doinsing Julian Ransangan Politeknik Sandakan Sabah Education HubBatu 10Jalan Sungai BatangSandakanSabah90000Malaysia Borneo Marine Research Institute Universiti Malaysia SabahJalan UMSKota Kinabalu88400Malaysia

Know.edge about the population dynamics w.thin a specific spatial area is vital for the effective planning and management of important fishery *** parameters,including the asymptotic length(L∞),grow.h coefficient(K),mortalities(Z,F,and M),recruitment pattern,exploitation level(E),and yield per recruit(Y’/R),of the tropical oyster Magallana bilineata in Mengkabong Bay,Tuaran,Malaysia w.re analyzed by using the FiSAT softw.re,using on the monthly shell length-frequency data collected from April 2019 to March 2020.A total of 435 oysters w.th shell lengths ranging from 3.64 to 11.16 cm w.re *** w.ter temperature,salinity,dissolved oxygen,hydrogen ion concentration(pH),and chlorophyll concentration w.re measured at 29.0-33.7◦C,26.68-35.74 psμ,3.18-6.99 mg/L,6.57-8.29 and 1.51-98.93μg/L,*** logarithmic relationship betw.en the length and w.ight of Log w.1.9055 Log L+0.1049(R2=0.5431)w.th exponent b of 1.9055 for combined sexes show.d a negative allometric grow.h(bw.h,including the use of genetically selected seeds,selection of new.farming sites and adoption of grow.out methods that favour high meat *** length(L∞)and grow.h coefficient(K)of the von Bertalanffy Grow.h Formula(VBGF)for *** w.re estimated at 12.13 cm and 1.00 yr􀀀1,*** theoretical ages at length zero(t0)(0.0487)w.re estimated by substituting L∞and K in Pauly’s *** sizes attained by *** w.re 3.76,5.04,6.13,7.05,7.83,and 8.49 cm at the end of 2,4,6,8,10,and 12 months,*** calculated grow.h performance index(φ)for *** in Mengkabong Bay w.s 2.168,w.ile the estimated lifespan w.s 3 *** recruitment pattern w.s observed year-round,w.th higher recruitment activities in September-October 2019 and January *** total mortality(Z)w.s analyzed using the length-converted

关键词： Crassostrea iredalei Length-w.ight relationship Grow.h parameters Recruitment Exploitation

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Geogenic Pollution of Groundw.ter Quality in Gampaha District, Sri Lanka: A Case Study of Groundw.ter Acidification from Rathupasw.la

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International Journal of Geosciences 2024年第8期15卷 590-604页

作者： Ishara Pathirage Anushka Upamali Rajapaksha S. P. Sucharitha Bandara G. w. A. Rohan Fernando Postgraduate Institute of Science University of Peradeniya Peradeniya Sri Lanka Instrument Centre Faculty of Applied Sciences University of Sri Jayewardenepura Colombo Sri Lanka Ecosphere Resilience Research Centre Faculty of Applied Sciences University of Sri Jayewardenepura Colombo Sri Lanka Central Environmental Authority Battaramulla Sri Lanka Department of Physics The Open University of Sri Lanka Colombo Sri Lanka

Over recent decades, Gampaha district, Sri Lanka, has experienced significant urbanisation and industrial grow.h, increasing groundw.ter demand due to limited and polluted surface w.ter resources. In 2013, a community uprising in Rathupasw.la, a village in Gampaha district, accused a latex glove manufacturing factory of causing groundw.ter acidity (pH w.ter;2) compare temporal variations in groundw.ter;and 3) explain acidification via a geochemical model. Seventy-tw. sample locations w.re tested for pH, electrical conductivity (EC), and anion concentrations (sulphate, nitrate, chloride and fluoride). Depth to the w.ter table and distance from the sea w.re measured to study variations across sandy, peaty, lateritic, and crystalline aquifers. Results show.d pH readings around 7 for sandy and crystalline aquifers, below.7 for peaty aquifers, and below.5 for lateritic aquifers, w.th significant w.ter table fluctuations near Rathupasw.la area. Principal component analysis revealed three principal components (PCs) explaining 86.0% of the variance. PC1 (40.6%) correlated w.th pH, EC, and sulphate (saltw.ter intrusion), w.ile PC2 (32.0%) correlated w.th nitrates and depth to the w.ter table (anthropogenic nutrient pollution). A geochemical transport model indicated a cone of depression recharged by acidic groundw.ter from peat-soil aquifers, leading to acidic groundw.ter in Rathupasw.la area. Previous attributions of acidic pH to the over-exploitation of groundw.ter by the latex factory have been reevaluated;the results suggest natural acidification from prolonged w.ter-rock interactions w.th iron-rich lateritic aquifers. Groundw.ter pH is influenced by local climate, geology, topography, and drainage systems. It is recommended that similar w.ter-rock interaction condit

关键词： Groundw.ter Acidification Acid Sulphate Soils (AAS) Ion Chromatography Groundw.ter Quality

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冲击工况下蜂窝密封封严特性研究

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机械工程师 2024年第7期 52-54,58页

作者：祝圣泉赵晶沈阳工业大学机械工程学院沈阳110000

大旋转机械系统中经常出现转子与定子的碰摩,已经成为工件损耗的主要因素之一。轻者引起机械故障,重者导致机毁人亡,造成重大经济损失。文中主要运用流固耦合的方法研究在冲击工况下蜂窝密封的泄漏量变化情况,研究发现:在转子与蜂窝密... 详细信息

大旋转机械系统中经常出现转子与定子的碰摩,已经成为工件损耗的主要因素之一。轻者引起机械故障,重者导致机毁人亡,造成重大经济损失。文中主要运用流固耦合的方法研究在冲击工况下蜂窝密封的泄漏量变化情况,研究发现:在转子与蜂窝密封碰撞瞬间,由于突然冲击破坏气流耗散平衡,泄漏量陡然增大,在腔内气流稳定后泄漏量又逐步减小,最后趋于稳定,当连续冲击时,相邻两次冲击后泄漏量增量大于前两次冲击泄漏量增量。

关键词：蜂窝密封泄漏量冲击工况流固耦合腔内涡旋

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基于负载估计的永磁同步电机复合自抗扰调速设计

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南京信息工程大学学报 2024年第4期16卷 537-543页

作者：李培康陆浩李娟李生权扬州大学电气与能源动力工程学院扬州225127

针对永磁同步电机(PMSM)调速系统中,存在的建模误差和负载突变等内外扰动影响转速稳定的问题,提出一种基于负载估计的复合自抗扰调速策略.首先,在速度环采用自抗扰控制器替代PI控制器,以改善系统转速与超调之间的矛盾.其次,设计一个负... 详细信息

针对永磁同步电机(PMSM)调速系统中,存在的建模误差和负载突变等内外扰动影响转速稳定的问题,提出一种基于负载估计的复合自抗扰调速策略.首先,在速度环采用自抗扰控制器替代PI控制器,以改善系统转速与超调之间的矛盾.其次,设计一个负载转矩观测器,通过转速和电流信号直接对负载转矩进行实时的估计和补偿,来解决扩张状态观测器(ESO)对负载突变响应较慢的问题.最后,基于Matlab/Simulink环境搭建了复合自抗扰调速系统的半实物实验平台,并与传统PI控制和线性自抗扰控制进行对比验证.仿真和实验结果表明,所提出的基于负载估计的复合自抗扰控制策略相较于传统控制方法在负载突变时转速变化量减少了30%以上,具有较优越的抗干扰能力和调速性能.

关键词：永磁同步电机速度环控制自抗扰控制负载转矩观测器

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Tw.sted fiber microfluidics:a cutting-edge approach to 3D spiral devices

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Microsystems & Nanoengineering 2024年第1期10卷 193-202页

作者： Shunsuke Kato Daniel w.Carlson Amy Q.Shen Yuanyuan Guo Department of Electrical Information and Physics EngineeringSchool of EngineeringTohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Micro/Bio/Nanofluidics Unit Okinawa Institute of Science and TechnologyOnnaKunigami-gun 904-0495 OkinawaJapan Frontier Research Institute for Interdisciplinary Sciences(FRIS) Tohoku UniversityAoba-kuSendai 980-0845 MiyagiJapan Graduate School of Biomedical Engineering Tohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Department of Physiology Graduate School of MedicineTohoku UniversityAoba-kuSendai 980-8575 MiyagiJapan

The development of 3D spiral microfluidics has opened new.avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological *** traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates Dean drag forces,eliminating the necessity for external fields in fluid ***,fabricating 3D spiral microfluidics remains a labor-intensive and costly endeavor,hindering its w.despread ***,conventional lithographic methods primarily yield 2D planar devices,thereby limiting the selection of materials and geometrical *** address these challenges,this w.rk introduces a streamlined fabrication method for 3D spiral microfluidic devices,employing rotational force w.thin a miniaturized thermal draw.ng process,termed as *** innovation allow. for rapid prototyping of tw.sted fiber-based microfluidics featuring versatility in material selection and heightened geometric *** validate the performance of these devices,w. combined computational modeling w.th microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3D flow.*** results corroborate the presence of a steady secondary flow.underscoring the effectiveness of our *** 3D spiral microfluidics platform paves the w.y for exploring intricate microflow.dynamics,w.th promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems.

关键词： thereby straight tw.sted

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太湖区小微水体氮素内源释放-沉降动态规律

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农业环境科学学报 2024年第8期43卷 1859-1868页

作者：张声权林涵朱毅刘雪梅夏永秋华东交通大学土木建筑学院南昌330013 中国科学院南京土壤研究所江苏常熟农田生态系统国家野外观测研究站南京210008 河海大学农业科学与工程学院南京211100 中国科学院大学南京学院南京211135

为探究小微水体氮素内源释放-沉降的动态规律,本研究于2023年1月至11月期间,在太湖平原水网区选取了5个具有代表性的沟、塘、浜等小微水体进行连续监测。每月定期对上覆水体、沉积物以及沉降颗粒物样品进行采集,并同步测定氮浓度及理化... 详细信息

为探究小微水体氮素内源释放-沉降的动态规律,本研究于2023年1月至11月期间,在太湖平原水网区选取了5个具有代表性的沟、塘、浜等小微水体进行连续监测。每月定期对上覆水体、沉积物以及沉降颗粒物样品进行采集,并同步测定氮浓度及理化因子。基于孔隙水扩散模型,计算了沉积物-水界面NH_(4)^(+)、NO_(3)扩散通量,并同步计算了NH_(4)^(+)、NO_(3)沉降通量和NH_(4)^(+)、NO_(3)内源释放通量。研究结果表明,太湖平原水网区小微水体的氮素内源释放以NH_(4)^(+)为主,NH_(4)^(+)内源释放总量在224~9631 kg·km^(-2)·a^(-1)之间,扩散通量介于50~312 kg·km^(-2)·a^(-1),对水体氮浓度的贡献率为2.2%~15.1%。相较于河流、湖泊等大型水体,小微水体的内源贡献占比相对较低。进一步分析表明,上覆水与沉积物之间的浓度差以及流速等因素,是影响小微水体内源释放的关键。小微水体氮素内源污染较为严重,为有效降低氮素内源污染,应强化沉积物管理,严格把控外源污染物的输入,积极提升水体的自然净化能力,合理调控水体流速,并构建完善的监测与预警体系。

关键词：小微水体内源污染沉积物-水界面内源氮释放

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Exploring the Pathw.ys of Leprosy Patients from Their Communities to a Diagnosis in the Districts of Mayuge, Yumbe and Kasese-Uganda

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Advances in Infectious Diseases 2024年第2期14卷 346-373页

作者： Rose Kengonzi Stavia Turyahabw. Samuel Orach Lisa Gerw.ng-Adima Ronald w. Nyote Vincent Kamara Kabugho Faith Consolata Mpambara National Tuberculosis and Leprosy Program Ministry of Health Uganda Kampala Uganda Health Department Uganda Catholic Medical Bureau Kampala Uganda German Leprosy and Tuberculosis Relief Association Kampala Uganda National Tuberculosis and Leprosy Program Kampala Uganda

Background: Leprosy is know. to cause disability that leads to severe outcomes like stigma, discrimination, mental health problems and participation restriction. Furthermore, in cases of infectious leprosy, longer delays increase the risk for the spread of the disease. Despite being preventable and curable, a significant proportion of new.leprosy patients (39%) in 2019 had grade 2 (Described as Visible disability) at the time of diagnosis signifying late presentation. The aim of this study w.s to describe patient journeys from first symptoms suggestive of leprosy to a diagnosis and individual and community level factors associated w.th health seeking behavior of leprosy patients. Methods: This w.s a cross-sectional explorative study implemented in Kasese, Mayuge and Yumbe districts .A structured questionnaire w.s used to collect quantitative data. Qualitative assessment included patients, family members, health w.rkers, voluntary health teams and the district health team. Descriptive statistics w.re presented in terms of percentages, frequency tables, pie Charts and graphs for easy interpretation and discussion. Results: The results indicate that 53% of the respondents identified as female. The median age of the respondents being 34 years, w.th a range of 1 to 76 years (Mean: 44.7, Mode: 65, Standard-Deviation: 19.6, Kurtosis: 0.6). The most common first symptom noticed by respondents w.s skin lesions (65%) follow.d by deformities (18%) (P value = 0.05%) occurring mostly in the feet (P-value = 0.48). Majority (52%) of the patients had taken more than 24 months (SD 18.72 OR 2.75) for a diagnosis to be made w.th a maximum delay of over 60 months. The most common cause of delay in seeking health care w.s lack of know.edge on leprosy (P value=Conclusions: There w.s a delay of 2 years in seeking health care for the majority of the patients. Key barriers to early diagnosis w.re lack of know.edge and infrastructure. Community sensitization and strengthening capacity buildi

关键词： Leprosy Patient Pathw.y Skin Lesions Disability Discrimination Delayed Diagnosis

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Accumulation of Heavy Metals in Maga-Pouss Rice Fields (Far-North Region, Cameroon) and Transfer to Rice Grains

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Agricultural Sciences 2024年第3期15卷 311-326页

作者： Diane Madomguia Gilbert Bello Basokdou Kalieu w. Appoline Isabelle Patrice Kuitekam Dongo Edouard Nya Serge Hubert Zebaze Togouet Department of Hydraulics and w.ter Management National Advanced School of Engineering University of Maroua Maroua Cameroon Research Center of Global Studies w.th Multidisciplinary Units (CREGUM) Maroua Cameroon National Laboratory of Analysis of Agricultural Inputs and Products Ministry of Agriculture and Rural Development Messa-Yaoundé Cameroon Department of Animal Physiology and Biology Faculty of Sciences University of Yaoundé I Yaoundé Cameroon

Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic w.rldw.de over the last tw. decades. The present study w.s carried out to determine the accumulation of heavy metals in rice fields and their transfer to rice grains. Soil, irrigation w.ter and rice grains samples w.re gathered in Maga-Pouss, Far-North, Cameroon. Concentrations of six heavy metals (lead, cadmium, zinc, copper, iron and mercury) w.re evaluated by Atomic Absorption Spectrophotometer (AAS). Mercury w.s not detected in this study. Average concentrations of metals w.re in this order (in mg/kg): Fe (188.60 ± 97.06) > Pb (63.63 ± 7.11) > Cd (2.59 ± 0.29) > Zn (1.10 ± 1.05) > Cu (0.80 ± 0.73) in w.ter and Pb (105.50 ± 31.11) > Fe (105.50 ± 31.11) > Cu (45.93 ± 14.39) > Zn (22.52 ± 6.40) > Cd (3.15 ± 0.49) in soil. w.ter in Maga-Pouss rice fields appears to be more harmful than the soil, notably for lead, cadmium and copper. In rice grains, heavy metals w.re found in this order (mg/kg): Fe (188.01 ± 82.62) > Cu (27.20 ± 0.00) > Zn (23.61 ± 12.42) > Pb (19.50 ± 19.91) > Cd (2.02 ± 1.05). The mean bioconcentration factor (BCF) of metals from soil to rice grains w.s in the follow.ng order: Fe (2.60) > Zn (1.05) > Cd (0.64) > Cu (0.59) > Pb (0.18). From w.ter to rice grains, the order is: Cu (37.26) > Zn (22.49) > Cd (6.97) > Pb (2.74) > Fe (1.94). Rice field pH and electrical conductivity favored the uptake of lead, copper and cadmium by rice grains. The findings of this study w.ll be good documentation for risk assessment, and decision-making by environmental managers in this region.

关键词： Heavy Metals Rice Field Bioconcenration Factor Maga-Pouss Accumulation

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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington T.w.Buggey T.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite w.ll be bombarded by radiation w.ich gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s w.thin the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the tw. flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show.that there is a cluster of bright pixels in the flight spa re w.ich increases in size w.th tempe *** at the nominal ope rating tempe rature(-120℃) it is w.thin the procure ment ***,the devices meet the specifications w.en ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades w.th temperature in full frame *** any charge losses are recovered w.en binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

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Propofol w.th Varied Functions: A Potential Therapeutic Opportunity for Postoperative Nausea, Vomiting and Pruritus—A Narrative Review

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Open Journal of Anesthesiology 2024年第2期14卷 13-24页

作者： Thomas w. Anabah Fidelis Bayor David Z. Kolbila Terence Kunfire Dakurah Sylvanus Kampo Juventus B. Ziem Anaesthesia Unit Habana Medical Services Tamale Ghana Department of Anaesthesiology Lawra Municipal Hospital Ghana Health Service Lawra Ghana Department of Obstetrics and Gynecology School of Medicine University for Development Studies Tamale Ghana Department of Anaesthesia and Intensive Care School of Medical Sciences C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Medical Microbiology School of Medical Sciences C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

Background: Despite the advances in anesthetics and non-pharmacological techniques, the prevalence of postoperative nausea and vomiting in all patients remains high. It is one of the most common distressing symptoms that cause dissatisfaction among patients after anesthesia and surgery. A sub-hypnotic dose of propofol has been show. to reduce morphine-induced postoperative nausea, vomiting, and pruritus. This review.article w.ll provide sufficient know.edge on the role of propofol in minimizing opioid-induced postoperative nausea, vomiting, and pruritus by providing detailed information on propofol antiemetic and antipruritic effects, as w.ll as discussions based on empirically available data. Method: w. conducted a narrative review.of the literature published betw.en 1990 and 2023 from a range of databases;PubMed, BioMed Central, Biosis Preview., Nature, International Pharmaceutical Abstracts, Springer-Link, and Elsevier. Discussion and Conclusion: The literatures review.d in this study have demonstrated that propofol may have diverse therapeutic effects including antiemetic and antipruritic. The antiemetic effect of propofol may be an effective therapeutic approach for the prevention of postoperative nausea and vomiting. The literature also demonstrated that the use of propofol for sedation during surgery may as w.ll ameliorates opioids induced postoperative pruritus, w.ich may be beneficial to surgical patients. Also, it w.s demonstrated that prophylactic use of propofol may be an effective w.y of preventing nausea and vomiting and pruritus during opioid use.

关键词： Propofol Nausea Vomiting Antiemetic Antipruritic Surgery

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