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Analysis of Risk Factors in Fishing Activities in Lake Erçek (Van, Turkey) for Occupational Health and Safety 埃尔帕雷切克湖(土耳其范)渔业活动的职业健康与安全风险因素分析
IF 0.3 Pub Date : 2022-12-26 DOI: 10.4314/mejs.v14i2.3
Ö. Cengiz
Fishing activities have always been a dangerous profession and numerous factors have a direct or indirect impact on the health, safety, and working conditions of fishermen. The present study aims in order to reveal the risk factors affecting the occupational health and safety of small-scale fishermen in Lake Erçek (Van, Turkey). Data were obtained from fishermen by survey between March 2022 and May 2022 and evaluated using the” L type matrix” method. “Having no training in occupational health and safety (OHS)” and “Fatigue from irregular and long working hours” are the important risk factors that affect the working conditions of fishermen. This study will make a significant contribution to the work efficiency of the fishermen and the planning to be made in the following processes, by making a risk analysis in terms of occupational health and safety before the possible increase in the number of fishermen in Lake Erçek (Van, Turkey).    
捕鱼活动一直是一项危险的职业,许多因素对渔民的健康、安全和工作条件有直接或间接的影响。本研究旨在揭示影响eraperek湖(Van,土耳其)小规模渔民职业健康和安全的风险因素。在2022年3月至2022年5月期间,通过调查从渔民中获取数据,并使用“L型矩阵”方法进行评估。"没有接受职业健康和安全培训"和"不规律和长时间工作造成的疲劳"是影响渔民工作条件的重要危险因素。本研究将通过在erpaderek湖(土耳其Van)渔民数量可能增加之前进行职业健康和安全方面的风险分析,为渔民的工作效率和在以下过程中制定计划做出重大贡献。
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引用次数: 1
Gender Differentia Among Fish Farmers Within Ilorin Metropolis, Kwara State, Nigeria 尼日利亚夸拉州伊洛林大都会内养鱼户的性别差异
IF 0.3 Pub Date : 2022-12-26 DOI: 10.4314/mejs.v14i2.2
Ayeloja A. A, Jimoh W. A, Adebisi G. L, A. M. A
Gender differentia among fish farmers within the Ilorin metropolis, Kwara State, Nigeria was studied with the aim of evaluating the level of involvement of the different gender in fish production activities, accessing their access to credit, and the constraints faced by them. A multistage sampling technique using a structured questionnaire was adopted for this study, the sample size was 210 using a structured questionnaire. Data were analyzed using SPSS 16.0. 61.90% of respondents were male while 52.5% and 49.2% of female and male respondents respectively were in their active age group of < 30 years. Females were more involved in fish marketing (42.90%) and fish processing (48.75%). There exist a significant association (p<0.05) between gender and level of involvement in fish marketing (χ2=9.20, p<0.05), access to land (χ2=10.69, p<0.05), and fish production activities (χ2=11.83, p<0.05). Access to credit was poor. Constraints faced include poor access to credit facilities, inadequate information, high cost of feed production, and poor water quality. It is therefore recommended that access to credit facilities banks of agriculture, microfinance banks, and commercial banks should be improved on while fish farmers are also encouraged to form cooperative societies as it will improve the capacity building of farmers and ease their credit acquisition for farming activities.
研究了尼日利亚夸拉州伊洛林大都市养鱼户的性别差异,目的是评估不同性别参与鱼类生产活动的程度、获得信贷的机会以及他们面临的限制。本研究采用了结构化问卷的多阶段抽样技术,使用结构化问卷的样本量为210。数据采用SPSS 16.0进行分析。61.90%的受访者为男性,52.5%和49.2%的女性和男性受访者处于<30岁的活跃年龄组。女性更多地参与鱼类营销(42.90%)和鱼类加工(48.75%)。性别与参与鱼类营销的水平(χ2=9.20,p<0.05)、获得土地的机会(χ2=10.69,p<0.05)和鱼类生产活动(χ2=11.83,p<0.05)之间存在显著关联(p<0.05)。获得信贷的机会较差。面临的制约因素包括难以获得信贷、信息不足、饲料生产成本高以及水质差。因此,建议改善农业银行、小额信贷银行和商业银行获得信贷的机会,同时鼓励养鱼户组建合作社,因为这将改善农民的能力建设,并方便他们获得农业活动的信贷。
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引用次数: 0
Measurement of Radionuclides Concentration and Radiological Health Assessment of Some Selected Table Waters in Ilorin 伊洛林部分地表水放射性核素浓度测定及辐射卫生评价
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.5
Orosun M M, Fabowale P A, Akinyose F C, Oluyide S O, Mark U, Olaniyan T A, Oduh V O
In order to ensure radiation monitoring and protection, an investigation and assessment of radiological risks that may be associated with the consumption of table waters commonly consumed in Ilorin, Nigeria, was carried out. The activity concentration level of 238U, 232Th, and 40K was determined using thallium activated 3˝×3˝ [NaI(TI)] detector connected to ORTEC 456 amplifier. The radiological risks due to the consumption of the samples were then estimated. The highest annual effective dose (AED) values were obtained from VW and the minimum was obtained from UW water. The AED decreases in the order VW>HW>IW>MW>DW>UW. This implies that VW water constitutes more radiation exposure followed by HW, IW, MW, DW, and then UW Water. The values estimated for MW, DW, and UW water were all lower than the world average value of 1 mSv/y and hence pose no serious radiation hazard. While the values estimated for VW, IW, and HW waters were slightly higher than the recommended threshold value, suggesting a possible risk of radiation exposure to customers. The Excess Lifetime Cancer Risks corroborated the findings of the AED, implying that the probability of developing cancer is high for most of the water samples. Since the values of the estimated hazard parameters were mostly higher than the recommended limits for all age groups, it is recommended that public water system should be monitored and efforts should be made to educate and enlighten the public on radiation exposure, its health effects, and remedial actions necessary to reduce radionuclides concentration in drinking water.
为了确保辐射监测和保护,对可能与尼日利亚伊洛林通常消费的饮用水有关的辐射风险进行了调查和评估。利用连接ORTEC 456放大器的铊活化3“×3”[NaI(TI)]检测器测定了238U、232Th和40K的活性浓度水平。然后估计了因食用这些样品而产生的辐射风险。年有效剂量(AED)值最高的是VW水,最低的是UW水。AED的减小顺序为:VW b> HW b> IW b> MW b> DW b> UW。这意味着大众水构成更多的辐射暴露,其次是HW, IW, MW, DW,然后是UW水。MW、DW和UW水的估算值均低于1 mSv/y的世界平均值,不构成严重的辐射危害。而VW, IW和HW水域的估计值略高于建议的阈值,这表明消费者可能面临辐射暴露的风险。过量的终身癌症风险证实了AED的发现,这意味着对大多数水样来说,患癌症的可能性很高。由于估计的危害参数值大多高于所有年龄组的建议限值,因此建议对公共供水系统进行监测,并努力教育和启发公众了解辐射照射、其对健康的影响以及减少饮用水中放射性核素浓度所需的补救行动。
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引用次数: 0
Coating Properties of Alkyd Resin, Epoxy Resins and Polyurethane Based Nanocomposites: A Review 醇酸树脂、环氧树脂和聚氨酯基纳米复合材料的涂层性能综述
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.1
Ikhazuagbe H Ifijen, Nyaknno U Udokpoh, Gregory E Onaiwu, Eribe M Jonathan, Esther U Ikhuoria
The uniqueness of alkyd resin, epoxy resin, and polyurethane nanocomposites has brought prominent recognition to the field of heavy-duty coating materials. This is expected due to the collaborative features of nano-sized materials such as the high surface area to volume ratio, great functionality per-unit space, extremely small sizes with high density, and that of alkyd resin, epoxy resin, and polyurethane (biodegradability, great gloss retention, adaptability, flexibility, durability, good drying properties, and weathering resistance). The objective of this review was to analyze the extent and currency of research and the development of alkyd, epoxy, and polyurethane nanocomposites in coating applications. Some of the several types of modifications discussed in this review are the incorporation of varying types of nanoclay and metal nanoparticles materials into alkyd resins, the incorporation of carbon nanotubes, MGel-graphene oxide (GO)/gelatin (MGel), Ni (II) Complex-Zeolite and starch-modified nano-ZnO into epoxy resin and the incorporation of (Rb2Co(H2P2O7)2.2H2O), modified nanoparticles of ZnO, diminished graphene oxide (dGO) into polyurethane and their effects on coating applications. The various studied modifications resulted in nanocomposite end-products with much improved properties. However, there are several challenges to the development of nanocomposites that need urgent attention. Some of the challenges discussed are the difficulty involved in transforming fabricated nanocomposites from laboratory to commercialized scale, the capital-intensive nature of synthesizing large nanopowder, etc.
醇酸树脂、环氧树脂和聚氨酯纳米复合材料的独特性为重型涂料领域带来了突出的认可。这是由于纳米材料的协同特征,如高表面积与体积比、每单位空间的大功能性、具有高密度的极小尺寸,以及醇酸树脂、环氧树脂和聚氨酯的协同特征(生物降解性、高光泽保持性、适应性、柔性、耐久性、良好的干燥性能和耐候性)。本综述的目的是分析醇酸树脂、环氧树脂和聚氨酯纳米复合材料在涂料应用中的研究和发展范围和现状。本综述中讨论的几种类型的改性包括将不同类型的纳米粘土和金属纳米颗粒材料掺入醇酸树脂中,将碳纳米管、氧化石墨烯(GO)/明胶(MGel)、Ni(II)复合沸石和淀粉改性的纳米ZnO掺入环氧树脂中,将氧化石墨烯(dGO)还原成聚氨酯及其对涂层应用的影响。所研究的各种改性导致纳米复合材料的最终产品性能大大提高。然而,纳米复合材料的开发面临着一些挑战,亟待关注。所讨论的一些挑战包括将制备的纳米复合材料从实验室转化为商业化规模的困难,合成大纳米粉末的资本密集性质等。
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引用次数: 0
Investigations on Tribological Performance of Sisal Fiber Reinforced Polypropylene Composites 剑麻纤维增强聚丙烯复合材料摩擦学性能研究
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.3
Temesgen Berhanu Yallew, Mulubrhan Mokonen, Tsegay Tesfay
There has been an increase in global interest in the development of natural fiber-reinforced composites. Natural fibers extracted from plants are receiving more attention from researchers, scientists, and academics due to their use in polymer composites and their environmentally friendly nature and sustainability. Recently, sisal fiber-reinforced polymer composites have been used in a variety of engineering applications like aerospace, automotive, marine, and other mechanical components, where tribological properties are of prime consideration. In this endeavor, experiments have been conducted to determine the tribological behavior of sisal fiber-reinforced polypropylene composite. Pin-on-disc wear tests have been conducted on specimens at various combinations of sliding velocities (1-3 m/s), sliding distances (1000-3000 m), and applying normal loads (10-30N). Using Response Surface Method (RSM), a mathematical model has been developed to predict the friction and wear loss behavior of the sisal fiber-reinforced polypropylene (PP) composites. To ensure the validity of the developed model, the Analysis of variance (ANOVA) technique has been applied. Important process parameters and material variables that exert significant influence on sliding wear loss have been determined with the help of systematic experimentation. Scanning Electron Microscope (SEM) has been used to probe morphological observation of the worn surface. Results revealed that the highest volumetric wear loss has been recorded at the highest values of applied load and this has been supported by the morphological study demonstrated by the scratches, as well as wider and deeper plowing marks on the worn surfaces.
全球对天然纤维增强复合材料的开发越来越感兴趣。从植物中提取的天然纤维因其在聚合物复合材料中的应用以及其环保性和可持续性而受到研究人员、科学家和学者的更多关注。最近,剑麻纤维增强聚合物复合材料已被用于各种工程应用,如航空航天、汽车、船舶和其他机械部件,其中摩擦学性能是首要考虑因素。在这项工作中,已经进行了实验来确定剑麻纤维增强聚丙烯复合材料的摩擦学行为。在不同滑动速度组合(1-3 m/s),滑动距离(1000-3000 m) ,并施加正常负载(10-30N)。采用响应面法(RSM)建立了一个预测剑麻纤维增强聚丙烯(PP)复合材料摩擦磨损行为的数学模型。为了确保所开发的模型的有效性,应用了方差分析(ANOVA)技术。在系统实验的帮助下,确定了对滑动磨损损失有重大影响的重要工艺参数和材料变量。扫描电子显微镜(SEM)已被用于探测磨损表面的形态观察。结果表明,在施加载荷的最高值下,记录到了最高的体积磨损损失,这得到了划痕以及磨损表面上更宽、更深的犁痕所证明的形态学研究的支持。
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引用次数: 0
Pumped Hydro- Energy Storage System in Ethiopia: Challenges and Opportunities 埃塞俄比亚抽水蓄能系统:挑战与机遇
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.2
Dawit Abay Tesfamariam, Asfafaw T Hailesialssie, Muyiwa S. Adaramola
The shares of RE sources are rising because of global warming concerns and the depletion of fossil fuels. However, due to its intermittent nature sustainable power supply depends on the proper energy mix and energy storage. By 2025, Ethiopia has planned to export 24 TWh of energy. Accordingly, its power generation is incorporating different RE sources dominated by hydropower. This paper has reviewed the global up-to-date status of PHES and Ethiopia’s current energy situation and potential PHES. The objective of this paper is to show Ethiopia’s potential for PHES and serve as a “Green Battery’’ for the East Africa Power Pool (EAPP). The review shows that PHES can easily replace backup diesel generators used as a backup during a blackout.  Moreover, it showed the Policy barrier for energy storage in the Ethiopian National Energy Policy proclaimed in 1994 and its 2012 updated policy. Thus, Ethiopia’s energy policies need to consider PHES in its energy storage strategy while expanding its generation.  
由于对全球变暖的担忧和化石燃料的消耗,可再生能源的份额正在上升。然而,由于其间歇性,可持续电力供应取决于适当的能源组合和能源储存。到2025年,埃塞俄比亚计划出口24太瓦时的能源。因此,其发电采用了以水力发电为主的不同可再生能源。本文综述了全球PHES的最新状况以及埃塞俄比亚当前的能源状况和潜在的PHES。本文的目的是展示埃塞俄比亚PHES的潜力,并作为东非电力联营(EAPP)的“绿色电池”审查表明,PHES可以很容易地取代停电期间用作备用的备用柴油发电机。此外,它在1994年宣布的埃塞俄比亚国家能源政策及其2012年更新的政策中显示了能源储存的政策障碍。因此,埃塞俄比亚的能源政策在扩大发电量的同时,需要在其储能战略中考虑PHES。
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引用次数: 0
Age and growth of gilthead sea bream (Sparus aurata Linnaeus, 1758) from Northern Aegean Sea (Turkey) 北爱琴海(土耳其)金头鲷(Sparus aurata Linnaeus, 1758)的年龄和生长
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.6
Ö. Cengiz
The age and growth of gilthead sea bream (Sparus aurata Linnaeus, 1758) were studied in the present study. A total of 126 specimens were collected from commercial fishmongers during the period between January 2015 and December 2015 from the northern Aegean coasts of Turkey. Fork length and the total weight of aged specimens ranged from 29.5 to 48.0 cm and from 425.00 to 2100.00 g, with a mean of 38.5 cm and 101.23 g, respectively. The length-weight relationship was estimated as W = 0.0053FL3.03 (R2 = 0.95). The von Bertalanffy growth equations were computed as 𝐿∞ = 52.8 cm, k = 0.29 year-1, 𝑡0 = -1.25 year for all samples. The growth performance index (𝛷′) was found as 2.91. There is no study on the biology of the species for the northern Aegean Sea. Therefore, this study provides valuable information for the species in this area.
本文对金头鲷(Sparus aurata Linnaeus, 1758)的年龄和生长进行了研究。2015年1月至12月期间,从土耳其爱琴海北部海岸的商业鱼贩处共采集了126个标本。年龄标本叉长29.5 ~ 48.0 cm,总重量425.00 ~ 21000g,平均38.5 cm, 101.23 g。长度-权重关系估计为W = 0.0053FL3.03 (R2 = 0.95)。所有样本的von Bertalanffy生长方程计算为𝐿∞= 52.8 cm, k = 0.29 year-1,𝑡0 = -1.25 year。生长性能指数( ')为2.91。目前还没有对爱琴海北部的这种生物进行研究。因此,本研究为该地区的物种研究提供了有价值的信息。
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引用次数: 0
Improved Receiver Design Concepts for Parabolic Dish Direct Solar Cooking Systems 改进的抛物面碟直接太阳能烹饪系统接收器设计概念
IF 0.3 Pub Date : 2022-10-22 DOI: 10.4314/mejs.v14i1.4
Austin P Theu, Cuthbert Z M Kimambo
In developing countries, solar cooking technology is considered one of the key measures in dealing with deforestation and environmental pollution.  However, their adoption and utilization have been insignificant due to social, cultural, and technical challenges, among others. For parabolic dish direct solar cookers, one of the critical and most important components of the system is a receiver since its performance greatly affects the entire system. This paper presents part of the findings of the study which investigated the prospects of improving the technical performance of parabolic dish direct solar cooking systems by focusing on the identification of prospective heat loss reduction mechanisms on the receiver. The study identified the Insulated (IR), Air-filled (AFR), and Oil-filled (OFR) receivers with Base Circular Rings (BCR) as alternatives to the Conventional Receiver (CR) System. Tests were conducted using procedures and protocols given by the American Society for Agricultural Engineers (ASAE). The test results showed that the average power developed by the systems was 185 W for the IRBCR system, 90 W for the OFRBCR system, 92 W for the AFRBCR system, and 118 W for the CR system. The standardized cooking power for a temperature difference of 50oC, PS (50), was 291 W for the IRBCR system, 11 W for the OFRBCR system, 272 W for the AFRBCR system, and 142 W for the CR system. The results further revealed that the overall efficiencies were 23% for the IRBCR system, 9% for the OFRBCR system, 12% for the AFRBCR system, and 18% for the CR system. The receiver efficiencies were found to be 27% for a system with IR, 11% for a system with OFR, 14% for a system with AFR, and 21% for a system with CR. The study concluded that the performance improved when the system with the IR was used while the magnitudes of the performance parameters of the AFR and OFR were lower than the CR system.
在发展中国家,太阳能烹饪技术被认为是处理森林砍伐和环境污染的关键措施之一。然而,由于社会、文化和技术等方面的挑战,它们的采用和利用一直微不足道。对于抛物面直接太阳能炊具,系统中最关键和最重要的部件之一是接收器,因为它的性能极大地影响整个系统。本文介绍了该研究的部分结果,该研究通过重点确定接收器上的预期热损失减少机制,研究了提高抛物面盘直接太阳能烹饪系统技术性能的前景。该研究确定了带有基环(BCR)的绝缘(IR)、充气(AFR)和充油(OFR)接收器作为传统接收器(CR)系统的替代方案。试验采用美国农业工程师协会(ASAE)给出的程序和方案进行。试验结果表明:IRBCR系统的平均功率为185 W, OFRBCR系统为90 W, AFRBCR系统为92 W, CR系统为118 W。在50℃(PS(50))温差下,IRBCR系统的标准蒸煮功率为291 W, OFRBCR系统为11 W, AFRBCR系统为272 W, CR系统为142 W。结果进一步表明,IRBCR系统的总效率为23%,OFRBCR系统为9%,AFRBCR系统为12%,CR系统为18%。研究发现,红外系统的接收效率为27%,OFR系统的效率为11%,AFR系统的效率为14%,CR系统的效率为21%。研究得出结论,当使用IR系统时,性能得到改善,而AFR和OFR的性能参数值低于CR系统。
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引用次数: 0
Challenges and Opportunities of Backyard Poultry Production in Ezha District, Gurage Zone of Ethiopia 埃塞俄比亚古拉格区埃扎区后院家禽生产的挑战与机遇
IF 0.3 Pub Date : 2022-04-11 DOI: 10.4314/mejs.v13i2.7
Mebagebriael Estifanos, Gebrehiwot Tadesse
This study was conducted with the objective of assessing the opportunities and challenges of backyard poultry production at three villages in Ezha district, Gurage Zone of southern Ethiopia using a semi-structured questionnaire, field visit and interview with 150 randomly selected respondents. The dominant chicken production system in the study area was an extensive system (74%) with scavenging and seasonal supplementary feeding (53%). Grains are the main feed used. Almost 65% of poultry share the same room with the main house with perch, the rest 20%, and 15%, respectively, use the different shelters. Most of the farmers (80%) use traditional medicine to treat their chicken. The average age of first laying was 5months, mean number of eggs per clutch was 12. The mean clutch size was 3.3 and the hatchability percentage was 72%. The result revealed that the main constraints of village poultry production in the study area, especially in village2 were predator (48%), disease (33.7%), feed shortage (19.3%), market (10%), and the primary opportunity was extension (34%) followed by credit, (24.6%), market (23.4%) and feed access (18%) and, respectively. It is concluded that constraints and opportunities of village chicken production were identified. Controlling predators, improving the management practices, and educating the framers are viable options to improve the livelihood of the households.        
本研究在埃塞俄比亚南部古拉格区Ezha区的三个村庄进行,目的是通过半结构化问卷调查、实地访问和随机选择的150名受访者的访谈,评估后院家禽生产的机遇和挑战。研究区主要的养鸡生产系统为粗放系统(74%),并伴有腐食和季节性补充饲养(53%)。谷物是主要的饲料。几乎65%的家禽与有栖木的主舍共用一个房间,其余20%和15%分别使用不同的庇护所。大多数农民(80%)使用传统药物治疗他们的鸡。平均首产年龄为5个月,平均每窝产12枚蛋。平均窝数3.3个,孵化率72%。结果表明,研究区特别是2村农村家禽生产的主要制约因素为捕食者(48%)、疾病(33.7%)、饲料短缺(19.3%)和市场(10%),主要制约因素为推广(34%),其次是信贷(24.6%)、市场(23.4%)和饲料获取(18%)。总结了农村鸡生产的制约因素和机遇。控制捕食者、改进管理做法和教育农民是改善家庭生计的可行选择。
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引用次数: 0
Eighth order Predictor-Corrector Method to Solve Quadratic Riccati Differential Equations 求解二次Riccati微分方程的八阶预测校正法
IF 0.3 Pub Date : 2022-04-11 DOI: 10.4314/mejs.v13i2.2
Wase Kassahun, Alemayehu Shiferaw, S. Gebregiorgis
In this paper, the eighth-order predictor-corrector method is presented for solving quadratic Riccati differential equations. First, the interval is discretized and then the method is formulated by using Newton’s backward difference interpolation formula. The stability and convergence of the method have been investigated. To validate the applicability of the proposed method, two model examples with exact solutions have been considered and numerically solved. Maximum absolute errors are presented in tables and figures for different values of mesh size h and the present method gives better results than some existing numerical methods reported in the literature.  
本文提出了求解二次里卡第微分方程的八阶预测校正方法。首先对区间进行离散化,然后利用牛顿的后向差分插值公式对方法进行求解。研究了该方法的稳定性和收敛性。为了验证所提方法的适用性,考虑了两个具有精确解的模型实例,并进行了数值求解。表格和图中给出了不同网格尺寸h值下的最大绝对误差,与现有文献报道的一些数值方法相比,本文方法的结果更好。
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引用次数: 0
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Momona Ethiopian Journal of Science
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