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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

Antibacterial activity of leaves and inter-nodal callus extracts of Mentha arvensis L

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Asian Pacific Journal of Tropical Medicine 2011年第3期4卷 196-200页

作者： johnson M wesely EG Kavitha MS Uma V Department of Plant Biology and Plant Biotechnology St.Xavier's College(Autonomous)Palayamkottai-627 002Tamil NaduIndia Department of Botany Arignar Anna Government Arts CollegeNamakkalTamil NaduIndia Centre for Biotechnology Muthayammal College of Arts and ScienceNamakkal Dist.Rasipuram-637 408Tamil NaduIndia Department of Botany V.H.N.S.N.CollegeVirudhunagar-626 001Tamil NaduIndia

Objective:To determine the anti-bacterial efficacy of chloroform,ethanol,ethyl acetate and water extracts of inter-nodal and leaves derived calli extracts from Mentha arvensis(***) against Salmonella typhi(***),Streptococcus pyogenes(***),Proteus vulgaris(P. vulgaris) and Bacillus subtilis(***).Methods:The inter-nodal and leaves segments of *** were cut into 0.5-0.7 cm in length and cultured on Murashige and Skoog solid medium supplemented with 3%sucrose,gelled with 0.7%agar and different concentration of 2,4-Dichlorophenoxyacetie acid(2,4-D) either alone or in *** preliminary phytochemical screening was performed by Brindha et al *** efficacy was performed by disc diffusion method and incubated for 24 h at 37℃.Results:Maximum percentage of callus formation(inter-nodal segments 84.3±0.78;leaves segments 93.8±1.27) was obtained on Murashige and Skoog’s basal medium supplemented with 3%sucrose and 1.5 mg/L of 2,*** ethanol extracts of leaves derived calli showed the maximum bio-efficacy than other *** leaves and stem derived calli extracts on Proteus *** that the plants can be used in the treatment of urinary tract infection associated with Proteus *** the bacterial efficacy studies,it is confirmed that the in vitro raised calli tissue was more effective compared to in vivo ***:The bio-efficacy study confirmed that the calli mediated tissues showed the maximum zone of *** present study paved a protocol to establish high potential cell lines by in vitro culture.

关键词： In vitro Callus Bacterial efficacy Mentha

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

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Modern systematics and environmental significance of stable isotopic variations in wanxiang Cave, wudu,Gansu, China

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Chinese Science Bulletin 2004年第15期49卷 1649-1652页

作者： KathleenR.johnson LvnnInaram ZHANGXinli VVANGSumin PANGFushun LONGLude DepartmentofEarthandPlanetarySciences UniversityofCaliforniaBerkeleyCAUSA TheScientificInformationCenterforResourcesandEnvironment ChineseAcademyofSciencesLanzhou730000China NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjing210008China wuduAdministrationUnitofwanxiangCave Wudu746000China

This paper presents the stable isotopic compo- sitions from the cave dripwater and actively forming soda straw stalactites collected from wanxiang Cave, wudu, Gansu, located on the Qinghai-Tibetan Plateau and Loess Plateau transition zone, China. The δ Odw and δ Ddw of 18 dripwater samples in the cave plot directly on the local MwL, constructed by using GNIP data from 3 sites surrounding the cave regions (Lanzhou, Xi’an, and Chengdu), the nearest site to the cave, suggesting that there is a close relationship be- tween the δ 18Odw of the cave water and the δ 18O of the pre- cipitations. Using the measured δ Odw and δ Omc values 18 18 from the mid-farthest parts from the cave entrance and the carbonate paleotemperature equation, the calculated tem- peratures range from 8.9 to 12.4℃, with the mean value of 10.7℃ and the temperature calculated at 8 locations in the farthest part of the cave is in the range of 10.1—12.4℃, with the mean value of 11.5℃, being consistent with the survey value(10.99℃)in the cave, slightly lower than the mean an- nual temperature (14.4℃) in wudu. This suggests that mod- ern speleothems are forming under isotopic equilibrium and their isotopic composition accurately reflects the mean an- nual temperature at the surface, indicating that the isotopic composition of the modern speleothems records local tem- perature change with credibility.

关键词：青藏高原黄土高原中国现代分类学稳定同位素变化氢同位素氧同位素岩洞水滴气候变化洞穴堆积物

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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

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

Detecting MoS2 and MoSe2 with optical contrast simulation

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Progress in Natural Science:Materials International 2019年第6期29卷 667-671页

作者： Xiaohe Zhang Hiroyo Kawai Jing Yang Kuan Eng johnson Goh Victoria Junior College Institute of Materials Research and Engineering A*STAR (Agency for Science Technology and Research) Department of Physics Faculty of Science National University of Singapore

Optical imaging is a promising method to identify and locate 2D materials efficiently and non-invasively. By putting a 2D material on a substrate, the nanolayer will add to an optical path and create a contrast to the case when the nanolayer is absent. This optical contrast imaging can be used to identify the 2D material and its number of layers. To make the optical imaging process in the laboratories an effective tool, Fresnel Law as a model was used to simulate the optical imaging results of 2D materials(graphene, Mo S2 and MoSe2) on top of different thickness of SiO2and Si wafer in the present investigation. The results provide the details of the optimal conditions(optimal light wavelength and optimal SiO2thickness) to identify and locate single to few 2D nanolayers, which can be used directly in laboratories. The optical contrasts of 1–5 layers of molybdenum disulfide(MoS2) and molybdenum diselenide(MoSe2) were simulated. To the best of our knowledge, it is the first time that the optical contrast results of MoSe2have been reported. In particular, this work highlights the sensitivity of the model on the accuracy of the refractive indices used. It is demonstrated that through computational modeling that optical contrast can allow effective determination of number of layers in few layer 2D materials.

关键词： 2D materials Optical imaging Substrate Fresnel law

Deep learning's fitness for purpose:A transformation problem frame's perspective

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CAAI Transactions on Intelligence Technology 2023年第2期8卷 343-354页

作者： Hemanth Gudaparthi Nan Niu Yilong Yang Matthew Van Doren Reese johnson Department of EECS University of CincinnatiCincinnatiOhioUSA School of Software Beihang UniversityBeijingChina Metropolitan Sewer District of Greater Cincinnati CincinnatiOhioUSA

Combined sewer overflows represent significant risks to human health as untreated water is discharged to the ***,such as the Metropolitan Sewer District of Greater Cincinnati(MSDGC),recently began collecting large amounts of water-related data and considering the adoption of deep learning(DL)solutions like recurrent neural network(RNN)for predicting overflow ***,assessing the DL's fitness for the purpose requires a systematic understanding of the problem *** this study,we propose a requirements engineering framework that uses the problem frames to identify and structure the stakeholder concerns,analyses the physical situations in which the highquality data assumptions may not hold,and derives the software testing criteria in the form of metamorphic relations that incorporate both input transformations and output *** our framework to MSDGC's overflow prediction problem enables a principled way to evaluate different RNN solutions in meeting the requirements.

关键词： deep learning deep neural networks software engineering

Influence of Soil Properties on Zinc Solubility Dynamics Under Different Redox Conditions in Non-Calcareous Soils

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Pedosphere 2017年第1期27卷 96-105页

作者： Michelle Anne Belen BUNQUIN Susan TANDY Sarah johnson BEEBOUT Rainer SCHULIN Crop and Environmental Sciences Division International Rice Research InstituteCollegeLos Banos Soil Protection Institute of Terrestrial EcosystemsETH Zurich

Zinc(Zn) deficiency in paddy soils is often a problem for rice *** can decrease metal availability in some noncalcareous soils through different mechanisms associated with soil redox *** experiments were performed in order to better understand the processes that governed the dynamics of Zn in non-calcareous paddy soils at varying redox potentials(Eh).Airdried non-calcareous soil samples collected from four different paddy field sites in the Philippines were submerged and incubated in a reaction cell with continuous stirring and nitrogen purging for 4 weeks,and then purged with compressed air for another week to reoxidize the *** Eh of the four soils started at 120 to 300 mV,decreased to —220 to —300 mV after 100 to 250 h of reduction,and was maintained at this low plateau for about 2 weeks before increasing again upon *** solubility showed contrasting patterns in the four soils,with two of the soils showing a decrease in soluble Zn as the Eh became low,probably due to zinc sulfide(ZnS) *** contrast,the other two soils showed that Zn solubility was maintained during the reduced phase which could be due to the competition with iron(Fe) for precipitation with *** in the relative amounts of S,Fe,and manganese(Mn) oxides in the four soils apparently influenced the pattern of Zn solubility after flooding.

关键词： microcosm paddy soil precipitation rice soil sulfide speciation Zn availability

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