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Modelling joint distribution of tree diameter and height using Frank and Plackett copulas

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Journal of Forestry Research 2020年第5期31卷 1681-1690页

作者： Friday Nwabueze Ogana Jose Javier Gorgoso-Varela johnson Sunday Ajose Osho Department of Social and Environmental Forestry University of IbadanIbadanNigeria Department of Innovation Fora Forest TechnologiesLugoSpain

Bivariate distribution models are veritable tools for improving forest stand volume *** accuracy depends on the method of ***-date,most bivariate distributions in forestry have been constructed either with normal or Plackett *** this study,the accuracy of the Frank copula for constructing bivariate distributions was *** effectiveness of Frank and Plackett copulas were evaluated on seven distribution models using data from temperate and tropical *** bivariate distributions include:Burr III,Burr XII,Logit-Logistic,Log-Logistic,generalized Weibull,Weibull and *** likelihood was used to fit the models to the joint distribution of diameter and height data of Pinus pinaster(184 plots),Pinus radiata(96 plots),Eucalyptus camaldulensis(85 plots)and Gmelina arborea(60 plots).Models were evaluated based on negative log-likelihood(-ΛΛ).The result show that Frank-based models were more suitable in describing the joint distribution of diameter and height than most of their Plackett-based *** bivariate Burr III distributions had the overall best *** Frank copula is therefore recommended for the construction of more useful bivariate distributions in forestry.

关键词： Bivariate distributions Frank copula Plackett copula Diameter Height

Effect of dietary near ideal amino acid profile on heat production of lactating sows exposed to thermal neutral and heat stress conditions

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Journal of Animal Science and Biotechnology 2021年第2期12卷 739-754页

作者： S.Zhang J.S.johnson N.L.Trottier Department of Animal Science Michigan State UniversityEast Lansing 48824USA USDA-ARS Livestock Behavior Research Unit West Lafayette 47907USA

Background:Reduced protein diet manifested potential to mitigate heat production based on the concept of ideal amino acid *** hypothesis of this study was that lactating sows fed a low crude protein(LCP)diet with supplemental amino acid produce less heat compared to those fed a high crude protein(HCP)diet under both thermal neutral(TN)and heat stress(HS)***:Thirty-two lactating sows were allotted to HCP(193 g CP/kg)and LCP(140 g CP/kg)diets under thermal neutral(TN,21±1.5°C)or cycling heat stress(HS,32±1.5°C daytime and 24±1.5°C nighttime)*** contained 0.90%SID lysine and 10.8 MJ/kg net *** pressure indirect calorimeters were used to measure gas exchange in individual sows with litters,and individual piglets on days 4,8,14 and *** and litter weights were recorded on days 1,10 and ***:Sow total heat production(THP)was calculated by subtracting litter THP from sow+litter THP based on *** BW and body protein(BP)loss was greater for LCP diet compared to HCP diet in peak lactation(P<0.05 and P<0.01,respectively)and throughout the entire lactation period(P<0.05 and P=0.056,respectively)under HS ***-stressed sows fed HCP diet had higher(P<0.05)rectal temperature at 13:00(P<0.05)and 19:00(P<0.01),and higher respiration rate at 07:00(P<0.05),13:00(P<0.05)and 19:00(P<0.05)compared to TN sows fed HCP *** sows fed LCP diet,those under HS tended to have higher(P=0.098)rectal temperature at 13:00 and had higher(P<0.05)respiration rate at 07:00,13:00 and 19:00 compared to TN *** relationship between daily THP and days in lactation of sows fed LCP diet was quadratic(P<0.05),with an ascending trend until day 14 and a descending trend from days 14 to *** fed LCP diet had lower daily THP at day 18(P<0.001)compared to those fed the HCP diet under HS ***:Reduction in THP in sows fed LCP diet was largely associated with THP on day 18 of lactation under HS *** LCP die

关键词： Amino acid Heat stress Lactating sows Low protein diet Total heat production

Experimental Study on the Mechanical Properties,water Resistance and Shrinkage of Basic Magnesium Sulphate Cement Based-RPC

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Experimental Study on the Mechanical Properties,water Resist...

作者： Daniel johnson 西南科技大学

学位级别：硕士

活性粉末混凝土(RPC)是一种新型的水泥基材料,通过提高混凝土的密实度和火山灰活性,并降低水灰比来实现。它具有超高强度、高韧性、高耐用性,现已用于道路、桥梁等。碱式硫酸镁水泥(BMSC)是由轻烧氧化镁粉、七水硫酸镁、水和改性剂制成... 详细信息

活性粉末混凝土(RPC)是一种新型的水泥基材料,通过提高混凝土的密实度和火山灰活性,并降低水灰比来实现。它具有超高强度、高韧性、高耐用性,现已用于道路、桥梁等。碱式硫酸镁水泥(BMSC)是由轻烧氧化镁粉、七水硫酸镁、水和改性剂制成的三元体系胶凝材料,其主要水化产物是5·1·7相。本文设想使用外加剂和钢纤维来改善碱式硫酸镁RPC的耐水性、流动性、强度,并探讨了不同养护制度的效果(常温养护(ATC)、水养护(WC)、标准养护(SC)、热养护(TC))。结果表明,综合考虑其力学性能、耐水性和流动性,5%的CFBC和0.75%的减水剂用量制备的碱式硫酸镁水泥基RPC的效果最佳。碱式硫酸镁水泥基RPC(未掺入钢纤维)的28d抗压强度达到最大值为99.2MPa,而28d抗折强度的最高值为23.2MPa。进一步分析了钢纤维对碱性硫酸镁水泥基RPC流动性和力学参数的影响。结果表明,流动性随着钢纤维掺量的增加而降低,但强度不断提高。钢纤维掺量为2%时,28d抗折强度为25.3MPa,28d抗压强度为119.1MPa,流动性为189.7mm。通过比较浸入水中后的抗压强度和软化系数变化来测试碱式硫酸镁水泥基RPC的耐水性。使用XRD和SEM来分析试样浸水前后的微观结构,碱式硫酸镁水泥基RPC中Mg O水化成片状Mg(OH)的量大幅减少。碱式硫酸镁水泥基RPC显示出良好的耐水性,没有掺入纤维的试样软化系数为0.88,掺入2%钢纤维的试样软化系数为0.95。碱式硫酸镁水泥基RPC的最佳养护制度为:先常温养护7d,然后70℃热养护7 d,最后标准养护14 d,此时试样28d抗折强度为22.0MPa,28d抗压强度为108.8MPa。

关键词： BMSC 防水力学收缩密度 pH

Studies on isozymic variation among the South Indian species of Sphaerostephanos

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Asian Pacific Journal of Tropical Biomedicine 2011年第4期1卷 295-297页

作者： Irudayaraj Varaprasadham johnson Marimuthu Department of Plant Biology and Plant Biotechnology St.Xavier's College(Autonomous)PalayamkpttaiTamil NaduIndia

Objective:To explore the identity and phylogenetic relationships among the three medicinally important species of Sphaerostephanos from South India using isozymic ***:The young fronds were homogenized with 3.5 mL of ice-cold homogenizing buffer in a pre-chilled pestle and *** supernatant was subjected to electrophoresis as described by Anbalagan poly acrylamide gel *** solutions for isoperoxidase was prepared as per Smila method for the detection of ***:A total of six different bands in five different positions with different molecular weight/Rf values and four active zones have been observed in the isoperoxidase enzyme system of *** one band with MW/Rf 0.399 is common to two different species *** arbuscula(***) and Sphaerostephanos unitus(***).Among the remaining four bands,two bands(R_f.0.23,0.47)are present in Sphaerostephanos subtruncatus(***) and one distinct band has been observed individually in ***(R_f.0.507) and ***(R_f.0.56).Conclusions:The present preliminary molecular study through isozymic analysis shows the identity of all the three species and the present results confirm distinctness of these three species based on macromicromorphology,phytochemistry and cytology.

关键词： Sphaerostephanos Isoperoxidase Poly acrylamide gel electrophoresis Inter-specific variation Isozymic variation Isozymic profile Phylogenetic relationship

A Chromatographic Study on the Glycosides of Aerva lanata L.

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中国天然药物 2011年第3期9卷 210-214页

作者： Yamunadevi M Wesely EG johnson M Research&Development Centre Bharathiyar University Department of Botany Arignar Anna Government Arts College Department of Plant Biology and Plant Biotechnology St.Xavier's College(Autonomous)

AIM:In order to identify the HPTLC profile(bio-marker),at species level,for the identification and confirmation of crude drugs,HPTLC separation was initiated on different parts of Aerva lanata *** South ***:Preliminary phyto-chemical screening was done by the method of *** studies were carried out following Harborne and Wagner et al *** Ethyl acetate-ethanol-water(8:2:1.2)was employed as mobile phase for ***:The methanolic extract of stem,leaves,root,flowers and seeds of *** showed the presence of 23 different types of glycosides with 23 different Rf values with range 0.02 to *** general higher degree of glycoside diversity has been observed in vegetative parts when compared to the reproductive *** number(12)of glycosides has been observed in root followed by stem(9).CONCLUSION:The results of the present study supplemented the folkloric usage of the studied plants which possess several known and unknown bioactive com-pounds with *** isolating and identifying these bioactive compounds new drugs can be formulated to treat various diseases.

关键词： Glycosides HPTLC profile Fingerprint

Interactions between rodents and weeds in a lowland rice agro-ecosystem:the need for an integrated approach to management

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Integrative Zoology 2019年第4期14卷 396-409页

作者： Nyo Me HTWE Grant R.SINGLETON David E.johnson Plant Protection Division Department of AgricultureMinistry of AgricultureLivestock and IrrigationMyanmar International Rice Research Institute DAPO Box 7777Metro ManilaPhilippines Natural Resources Institute University of GreenwichChatham MaritimeKentUK

Rodents and weeds are important pests to rice crops in Southeast *** interaction between these 2 major pests is poorly *** temperate cereal systems,seeds of grass weeds can be an important food source for rodents and weed cover along crop margins provides important refuge for *** 2012 and 2013,a replicated study(n=4)in Bago,Myanmar compared 4 treatments(rodents and weeds;no rodents and weeds;rodents and no weeds;no rodents and no weeds)each of 0.25 ha in transplanted *** were managed with hand weeding in the wet season,and hand weeding and herbicides in the dry *** fences were installed to exclude *** examined the weed cover and relative abundance of weed species,rodent damage,rodent population dynamics and rice yield loss caused by rodents and *** dominant rodent species was Bandicota *** the dry season,Cyperus difformis was dominant at the tillering stage and Echinochloa crus-galli was the dominant weed species at the booting *** the wet season ***-galli was a dominant weed throughout the *** by rodents was higher in the dry *** were larger economic benefits for best weed management and effective rodent control in the dry season(258 US$/ha)than in the wet season(30 US$/ha).Concurrent control of weeds in and around rice fields combined with coordinated community trapping of rodents during the early tillering stage and ripening stage of rice are recommended management options.

关键词： Bandicota bengalensis Myanmar rice rodents weeds

Effect of Skin on Finite Element Modeling of Foot and Ankle During Balanced Standing

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Journal of Shanghai Jiaotong university(Science) 2018年第1期23卷 132-137页

作者：欧海华 QAISER Zeeshan 康利平 johnson Shane University of Michigan-Shanghai Jiao Tong University Joint Institute State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Experimental measurements of stresses and strains for lower extremity injuries(LEI) are invasive, and therefore, predictions require physiologically accurate 3D finite element(FE) models of the foot and ankle. In previous models, skin is typically neglected. However, experimental studies have shown that skin is much stiffer than soft tissue. In this study, the material sensitivity of skin on foot arch deformation is investigated. A finite element model of the foot is developed, incorporating bones, soft tissue, ligament, articulating surfaces, plantar aponeurosis, skin and plantar plate. Balanced standing is simulated without skin or with three different skin mechanical properties. By including different skin models, the foot static vertical stiffness, navicular displacement and plantar aponeurosis strain change significantly, when compared with the model without skin. The study shows that skin, showing a much stiffer behaviour than soft tissue, should not be neglected in the foot modelling. Further,the plantar plate considered in this model can give merit to modelling injuries such as plantar plate tearing.

关键词： finite element analysis foot and ankle hyperelastic material plantar plate

Preliminary phytochemical and antimicrobial studies on a spike-moss Selaginella inaequalifolia(hook.& grev.) Spring

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Asian Pacific Journal of Tropical Medicine 2010年第12期3卷 957-960页

作者： Varaprasadham Irudayaraj Janaky M Marimuthu johnson Nallayan Selvan Department of Plant Biology and Plant Biotechnology St.Xavier's College(Autonomous)Palayamkottai - 627 002Tamil NaduIndia Centre for Biotechnology Muthayammal College of Arts & ScienceRasipuram - 637 408Tamil NaduIndia

Objective:To screen the anti-cancer spike-mosses for the presence of various bioactivities and to identify the important bioactive chemicals present in Selaginella inaequalifolia(S. inaequalifolia)(Hook.& Grev.) ***:Preliminary phytochemical screening was done by following the method of Brindha et *** study was carried out by disc diffusion ***:Results of preliminary phytochemical screening on five different extracts(petroleum ether,benzene,chloroform,ethanol and distilled water) of the spike-moss *** show the presence steroids,triterpenes,phenolic group,tannin,sugars and ***,amino acids,anthraquinone and reducing sugar did not show any positive *** the five different extracts,ethanol and chloroform extracts show the presence of maximum number(4 each) of *** results on antimicrobial studies show that all the three microbes[Staphylococcus aureus(***),Escherichia coli(***) and Candida albicans (***)]tested are resistant to the ethanol extract and susceptible to petroleum ether *** petroleum ether extract shows maximum inhibition with 45 mm of inhibition zone in *** inhibition zone in *** and *** are 26 mm and 22 mm respectively. Conclusions:The present study shows *** having potent antibacterial and anticandidal activities.

关键词： Spike moss Selaginella inaequalifolia Phytochemical screening Antimicrobial activity

Testing the potential mechanisms for the maintenance of a genetic color polymorphism in bluefin killifish populations

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Current Zoology 2018年第6期64卷 733-743页

作者： Ashley M.johnson Chia-Hao CHANG Rebecca C.FULLER Department of Animal Biology School of Integrative BiologyUniversity of Illinois at Urbana-ChampaignChampaignIL 61820USA

The maintenance of genetic variation in the face of natural selection is a long-standing question in evolutionary *** the bluefin killifish Lucania goodei,male coloration is *** can produce either red or yellow coloration in their anal fins,and both color morphs are present in all *** 2 morphs are heritable and how they are maintained in nature is ***, we tested 2 mechanisms for the maintenance of the red/yellow color *** frequency-dependent mating success predicts that rare males have a mating advantage over common males. Spatial variation in fitness predicts that different color morphs have an advantage in different microhabitat *** a breeding experiment,we tested these hypotheses by creating populations with different ratios of red to yellow males (5 red:1 yellow;1 red:5 yellow)and determining male mating success on shallow and deep spawning *** found no evidence of negative frequency-dependent mating *** morphs tended to have higher mating success, and this was particularly so on shallow spawning ***,on deep substrates,red males enjoyed higher mating success than yellow males,particularly so when red males were rare. However,yellow males did not have an advantage at either depth nor when *** suggest that preference for red males is expressed in deeper water,possibly due to alterations in the lighting ***,male pigment levels were correlated with one another and predicted male mating ***,pigmentation plays an important role in male mating success.

关键词： carotenoid color polymorphism environmental heterogeneity melanin negative frequency dependence pterin