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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURAnO Jon Marx SARMIEnTO lar.y n.digal Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Petrographic composition of coal within the Benue Trough,nigeria and a consideration of the paleodepositional setting

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International Journal of Coal Science & Technology 2022年第3期9卷 67-90页

作者： A.D.Mangs n.J.Wagner O.M.Moroeng U.A.lar DSI-nRF CIMERA Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa Department of Geology University of JosJosNigeria

The petrographic composition of Cretaceous-age coals hosted in the Benue Trough,nigeria is presented and discussed in terms of the paleodepositional settings that infuenced the coal-bearing *** Benue Trough is a failed arm of the triple junction of an inland sedimentary basin that extends in a nE-SW direction from the Gulf of Guinea in the south,to the Chad Basin in the north.A total of twenty-nine(29)coal samples were obtained from nineteen coal localities in the Upper(UBT),Middle(MBT),and Lower Benue Trough(LBT).The high average volatile matter yield,low average ash yield,high calorifc value(24.82 MJ/kg,on average),and low sulphur values indicate good quality coal *** organic matter is dominated by vitrinite,reported at an average of 59.3%by volume(mineral-matter free).Variation was noted in the inertinite content across three *** macerals were not commonly observed in the studied samples and were absent in the MBT *** facies studies decipher the paleoenvironmental conditions under which the vegetation *** commonly used are the gelifcation index(GI),tissue preservation index(TPI),ground water index(GWI and variations),vegetation index(VI),and wood index(WI).Comparing the array of coal facies models applied,the MBT samples difer from the UBT and LBT samples,concurring with the coal quality *** UBT and LBT coals formed in an upper deltaic to drier piedmont plane depositional environment,while the MBT coal formed in a lower deltaic marsh to wet forest swamp depositional *** samples indicate an ombrotrophic *** view of the modifed equations and the plots used,interpreting depositional environments from just a single model is not reliable.

关键词： Benue Trough Coal petrography Depositional environment Microlithotypes Vitrinite

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The new era of cardiovascular research:revolutionizing cardiovascular research with 3D models in a dish

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Medical Review 2024年第1期4卷 68-85页

作者： yuan yang Hao yang Fedir n.Kiskin Joe Z.Zhang Institute of neurological and Psychiatric Disorders Shenzhen Bay LaboratoryShenzhenGuangdong ProvinceChina Institute of neurological and Psychiatric Disorders Shenzhen Bay LaboratoryShenzhen 518132Guangdong ProvinceChina

Cardiovascular research has heavily relied on studies using patient samples and animal ***,patient studies often miss the data from the crucial early stage of cardiovascular diseases,as obtaining primary tissues at this stage is *** animal models can offer some insights into disease mechanisms,although they usually do not fully recapitulate the phenotype of cardiovascular diseases and their *** recent years,a promising breakthrough has emerged in the form of in vitro three-dimensional(3D)cardiovascular models utilizing human pluripotent stem *** innovative models recreate the intricate 3D structure of the human heart and vessels within a controlled *** advancement is pivotal as it addresses the existing gaps in cardiovascular research,allowing scientists to study different stages of cardiovascular diseases and specific drug responses using human-origin *** this review,we first outline various approaches employed to generate these *** then comprehensively discuss their applications in studying cardiovascular diseases by providing insights into molecular and cellular changes associated with cardiovascular condi***,we highlight the potential of these 3D models serving as a platform for drug testing to assess drug efficacy and *** their immense potential,challenges persist,particular.y in maintaining the complex structure of 3D heart and vessel models and ensuring their function is comparable to real ***,overcoming these challenges could revolutionize cardiovascular *** has the potential to offer comprehensive mechanistic insights into human-specific disease processes,ultimately expediting the development of personalized therapies.

关键词： pluripotent stem cells three-dimensional(3D)models cardiac microtissues cardiac organoids vessel organoids organ-on-a-chip

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一种漂白工艺新型混合器及其应用

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湖北造纸 2000年第3期 44-48页

作者：罗惠芳黄志勇 lar E.nsman 中国轻工业武汉设计院 430060

本文简要地介绍了由瑞典ＳＵＮＤＳＤＥＦＩＢＲＡＴＯＲ公司研制的密集式剪切（ＳＭＡ）混合器的基本原理及其在现代化学制浆漂白工艺中的应用。使用ＳＭＡ混合器可以简化漂白工艺并可明显地减少化学药品消耗和投资。

关键词：漂白工艺化学制浆 SMA混合器中浓氧化处理

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Leg Length Discrepancy in Cementless Total Hip Arthroplasty

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Surgical Science 2011年第4期2卷 183-187页

作者： Christopher n Peck Karan Malhotra Winston y Kim 不详

The use of cementless total hip arthroplasty (THA) is on the increase. In order to achieve rotational and axial stability larger implants may be required than originally templated for. This could potentially result in a lar-ger leg length inequality. Our objective was to determine whether there is greater inequality in leg length post-operatively in cementless THA as compared to cemented implants. 136 consecutive patients undergoing elective THA between June 2007 and May 2008 were included. Post-operative digital radiographs were ex-amined to determine leg length. Twenty seven patients (20%) underwent a cemented procedure and 109 (80%) a cementless procedure. In the cemented group the mean leg length discrepancy was 7.3 mm (range 19 mm short to 21 mm long). In the cementless group the mean measured leg length discrepancy was 6.3 mm (range 18 mm short to 23 mm long). There was no significant difference between the two groups (P = 0.443). This study shows that with accurate pre-operative templating, both cemented and cementless proce-dures produce comparable and acceptable leg length discrepancies.

关键词： Hip Arthroplasty Cementless Leg Length

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Design and fluid-structure interaction analysis for a microfluidic T-junction with chemo-responsive hydrogel valves

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Applied Mathematics and Mechanics(English Edition) 2020年第6期41卷 939-952页

作者： E.KHAnJAnI A.HAJARIAn A.KARGAR-ESTAHBAnATy n.ARBABI A.TAHERI M.BAGHAnI School of Mechanical Engineering College of EngineeringUniversity of TehranTehran ***Iran Bourns College of Engineering University of CaliforniaRiversideCalifornia 92521U.S.A. Department of Mechanical Engineering University of British ColumbiaOntario V6T 1Z2Canada Department of Mechanical Engineering University of LarestanLar ***Iran

Due to the deformation ability even under small loads, hydrogels have been widely used as a type of soft materials in various applications such as actuating and sensing, and have attracted many researchers to study their behaviors. In this paper, the behavior of hydrogel micro-valves with reverse sensitivity to the p H inside a T-junction flow sorter is investigated. With the fluid-structure interaction(FSI) approach, the effects of various parameters such as the inlet pressure and the p H value on the stress and deformation of the micro-valves are examined, and the results with and without FSI,including the flow rate and the closure p H, are compared. In order to reduce the response time of hydrogels, the effects of three different patterns on the performance of the microvalves are explored. Eventually, it is concluded that FSI is a key influential factor in designing and analyzing the behaviors of hydrogels.

关键词： hydrogel pH-sensitive T-junction flow sorter fluid-structure interaction(FSI) micro-valve

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Inconsistent interspecific and intraspecific differentiation of climate envelopes in a subtropical tree

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Journal of Plant Ecology 2019年第1期12卷 176-185页

作者： Qiuchi Wan Zhuo Zheng Marta Benito-Garzón Rémy J.Petit School of Earth Science and Geological Engineering Sun Yat-sen University135 Xingang RoadHaizhu DistrictGuangzhou 510275China Biogeco INRAUniversity of Bordeaux69 Arcachon Road33610 CestasFrance

Aims Comparisons of climate envelopes among species have shown that niche conservatism tends to break down over ***,we use the Asian tree genus Platycarya(Juglandaceae)as a case study to test this tendency at relatively short timescales in a single ***,together with a reanalysis of the extant literature,should help evaluate prospects of using correlations between climate and spe-cies occurrence data to infer evolutionary *** We rely on species distribution models(SDMs)and multivari-ate analyses to compare current and past(Last Glacial Maximum~21ka)climatic envelopes between the two extant Platycarya spe-cies(Platycarya strobilacea and Platycarya longipes)and between mainland and Taiwan populations of ***,paying particu-lar attention to autocorrelation *** also review interpreta-tions provided in similar studies comparing climate envelopes between and within species,including in studies involving native and introduced populations of the same *** Findings We find intraspecific but not interspecific differentiation in climate envelopes of Platycarya,despite the prediction that niche differen-tiation should be stronger between older *** review also suggests that differentiation in climate envelopes need not imply rapid evolutionary *** SDMs can be used to raise evolutionary hypotheses to be validated with other data,we con-clude that it should not be used to directly infer short-term evolu-tionary processes.

关键词： climate envelope Last Glacial Maximum evolution Platycarya species distribution models

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Optimization Analysis of Sustainable Solar Power System for Mobile Communication Systems

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Computers, Materials & Continua 2022年第5期71卷 3243-3255页

作者： Mohammed H.Alsharif Raju Kannadasan Amir y.Hassan Wael Z.Tawfik Mun-Kyeom Kim Muhammad Asghar Khan Ahmad A.A.Solyman Department of Electrical Engineering College of Electronics and Information EngineeringSejong University209 Neungdong-roGwangjin-guSeoul05006Korea Department of Electrical and Electronics Engineering Sri Venkateswara College of EngineeringSriprumbudurChennai602117India Department of Power Electronics and Energy Conversion Electronics Research InstituteGiza12622Egypt Department of Physics Faculty of ScienceBeni-Suef UniversityBeni-Suef62511Egypt Department of Energy System Engineering Chung-Ang University84 Heukseok-roDongjak-guSeoul156-756Korea Department of Electrical Engineering Hamdard University Islamabad44000Pakistan Department of Electrical and Electronics Engineering Istanbul Gelisim UniversityAvcılar34310Turkey

Cellular mobile technology has witnessed tremendous growth in recent *** of the challenges facing the operators to extend the coverage of the networks to meet the rising demand for cellular mobile services is the power sources used to supply cellular towers with energy,especially in ***,switch from the conventional sources of energy to a greener and sustainable power model became a target of the academic and industrial sectors in many fields;one of these important fields is the telecommunication ***,this study aims to find the optimum sizing and technoeconomic investigation of a solar photovoltaic scheme to deploy cellular mobile technology infrastructure cleanly and *** optimal solarpowered system is designed by employing the energy-balance procedures of the HOMER software *** problem objective is considered in terms of cost,but the energy system is constrained to meet the power demand *** simulations were performed to determine the optimum sizing,performance and monetary cost of the power system,using long-term meteorological datasets for a case study site with defined longitude(31◦25E)and latitude(30◦06n).From the observed results,the total net present cost(nPC)of the proposed system is$28,***,these outcomes can provide profound economic,technical,and ecological benefits to cellular *** also ensures a sizeable reduction in greenhouse gas that supports sustainable green wireless network(Wn)deployment in remote areas.

关键词： Wireless networks green wireless networks green communications sustainability OPEX

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Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(S)nn=200 GeV

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Chinese Physics C 2021年第4期45卷 198-241页

作者： H.Agakishiev M.M.Aggarwal Z.Ahammed A.V.Alakhverdyants I.Alekseev J.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.S.Averichev J.Balewski D.R.Beavis n.K.Behera R.Bellwied M.J.Betancourt R.R.Betts A.Bhasin A.K.Bhat H.Bichsel J.Bieleik J.Bielcikova B.Biritz L.C.Bland W.Borowski J.Bouchet E.Braidot A.V.Brandin A.Bridgeman S.G.Brovko E.Bruna S.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai H.Caines M.Calderon de la Barca Sanchez D.Cebra R.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka S.Chattopadhyay H.F.Chen J.H.Chen J.y.Chen L.Chen J.Cheng M.Cherney A.Chikanian K.E.Choi W.Christie P.Chung M.J.M.Codrington R.Corliss J.G.Cramer H.J.Crawford S.Dash A.Davila Leyva L.C.De Silvat R.R.Debbe T.G.Dedovich A.A.Derevschikov R.Derradi de Souza L.Didenko P.Djawotho S.M.Dogra X.Dong J.L.Drachenberg J.E.Draper J.C.Dunlop L.G Efimov M.Elnim J.Engelage G Eppley M.Estienne L.Eun O.Evdokimov R.Fatemi J.Fedorisin A.Feng R.G.Fersch P.Filip E.Finch V.Fine y.Fisyak C.A.Gagliardi D.R.Gangadharan A.Geromitsos F.Geurts P.Ghosh y.n.Gorbunov A.Gordon O.Grebenyuk D.Grosnick S.M.Guertin A.Gupta W.Guryn B.Haag O.Hajkova A.Hamed L-X.Han J.W.Harris J.P.Hays-Wehle M.Heinz S.Heppelmann A.Hirsch E.Hjort G.W.Hoffmann D.J.Hofiman B.Huang H.Z.Huang T.J.Humanic L.Huo G.Igo P.Jacobs W.W.Jacobs C.Jena F.Jin J.Joseph E.G.Judd S.Kabana K.Kang J.Kapitan K.Kauder H.Ke D.Keane A.Kechechyan D.Kettler D.P.Kikola J.Kiryluk A.Kisiel V.Kizka A.G.Knospe D.D.Koetke T.Kollegger J.Konzer I.Koralt L.Koroleva W.Korsch L.Kotchenda V.Kouchpil P.Kravtsov K.Krueger M.Krus L.Kumar P.Kurnadi M.A.C.Lamont J.M.Landgraf S.LaPointe J.Lauret A.Lebedev R.Lednicky J.H.Lee W.Leight M.J.LeVine C.Lil L.Li n.Li W.Li X.Li X.Li y.Li Z.M.Li M.A.Lisa F.Liu H.Liu J.Liu T.Ljubicic W.J.Llope R.S.Longacre W.A.Love y.Lu E.V.Lukashov X.Luo G.L.Ma y.G.Mai D.P.Mahapatra R.Majka O.I.Mall L.K.Mangotra R.Manweiler S.Margetis C.Markert H.Masui H.S.Matis yu.A.Matulenko D.MeDonald T.S.McShane A.Meschanin R.Milner n.G.Minaev S.Mioduszewski A.Mischke M.K.Mitrovski B.Mohanty M.M.Mondal B.Morozov D.A.Morozov M.G.Munhoz M Argonne national Laboratory Argonnellinois 60439USA Brookhaven national Laboratory UptonNew York 11973USA University of Califomia BerkeleyCaliformnia 94720USA University of California DavisCalifornia 95616USA University of Califormnia Los AngelesCalifomia 90095USA Universidade Estadual de Campinas Sao PauloBrazil University of Illinois at Chicago ChicagoIlinois 60607USA Creighton University OmahaNebraska 68178USA Czech Technical University in Prague FNSPEPrague11519Czech Republic nuclear Physics Institute AS CR 25068 Rez/PragueCzech Republic University of Frankfurt FrankfurtGermany Institute of Physics Bhubaneswar 751005India Indian Institute of Technology MumbaiIndia Indiana University BloomingtonIndiana 47408USA Alikhanov Instiute for Theoretical and Experimental Physics MoscowRussia University of Jammu Jammu 180001India Joint Institute for nuclear Research Dubna141980Russia Kent State University KentOhio 44242USA University of Kentucky LexingtonKentucky40506-0055USA Institute of Modern Physics LanzhouChina Lawrence Berkeley national Laboratory BerkeleyCalifornia 94720USA Massachusetts Institute of Technology CambridgeMA 02139-4307USA Mx-Planck-Institut fir Physik MunichGermany Michigan State University East LansingMichigan 48824USA Moscow Engineering Physics Institute Moscow Russia nIKHEF and Utrecht University AmsterdamThe Netherlands Ohio State University ColumbusOhio 43210USA Old Dominion University NorfolkVA23529USA Panjab University Chandigarh 160014India PennsyIvania State University University ParkPennsylvania 16802USA Institute of High Energy Physics ProtvinoRussia Purdue University West LafayetteIndiana 47907USA Pusan national University PusanRepublic of Korea University of Rajasthan Jaipur 302004India Rice University HoustonTexas 77251USA Universidade de Sao Paulo Sao PauloBrazil University of Science&Technology of China Hefei 230026.China Shandong University JinanShandong 250100China Shanghai Institute of Applied Physics Shanghai 201800Chi

Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium,*** measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au *** modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching *** paper reports STAR measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(S)nn=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle *** subtractions of the combinatorial background and anisotropic flow,assuming Zero yield At Minimum(ZyAM),are *** correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow *** away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger *** near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately *** correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from *** is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak *** dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open *** with aФ_(s)-dependent elliptic flow,the away-side correlation structure

关键词： relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane

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原发性肝细胞肝癌射频消融术前血清HBeAg水平与术后复发的相关性

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中国临床医学 2016年第6期23卷 705-709页

作者：周颖婷谢晓莺干育红葛宁灵陈漪任正刚张岚复旦大学附属中山医院肝肿瘤内科上海200032

目的：探讨具有乙肝背景的肝细胞肝癌（hepatocellular carcinoma,HCC）患者射频消融术（radiofrequency ablation,RFA）术前血清乙型肝炎e抗原（HBeAg）水平与术后肿瘤复发的相关性。方法：回顾性分析2006年6月至2012年6月复旦大学附... 详细信息

目的：探讨具有乙肝背景的肝细胞肝癌（hepatocellular carcinoma,HCC）患者射频消融术（radiofrequency ablation,RFA）术前血清乙型肝炎e抗原（HBeAg）水平与术后肿瘤复发的相关性。方法：回顾性分析2006年6月至2012年6月复旦大学附属中山医院收治的具有乙肝背景的小HCC行RFA治疗的391例患者的临床资料。根据术前HBeAg水平,将患者分为HBeAg阳性组（n=112）和HBeAg阴性组（n=279）。术后定期规律随访,分析RFA术前HBeAg水平和RFA术后肿瘤复发的相关性。结果：HBeAg阳性组术后中位无复发生存期（recurrence-free survival time,RFS）为（23.00±1.99）个月,HBeAg阴性组术后中位RFS为（31.00±3.49）个月,差异有统计学意义（P=0.002）。多因素Cox风险回归分析显示,术前甲胎蛋白（alpha fetal protein,AFP）水平（HR 1.393,95%CI 1.052-1.845,P=0.021）、血清HBV-DnA水平分级（HR 1.402,95%CI1.013-1.939,P=0.041）和HBeAg水平（HR 1.389,95%CI 1.017-1.896,P=0.039）是影响乙肝背景小HCC RFA术后无瘤生存时间的独立危险因素。结论：原发性HCC RFA术前血清HBeAg水平与术后肿瘤复发密切相关,是原发性HCC RFA术后复发的独立危险因素。

关键词：原发性肝细胞肝癌射频消融术 HBeAg

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