检索结果-南通市图书馆

Analysis of Growth Characteristics and Differentially Expressed Homologous Genes in Rhodobacter sphaeroides under Normal and Simulated Microgravity Conditions

引用

Advances in Microbiology 2023年第11期13卷 539-558页

作者： weerakkody ranasinghe Eduardo Gutierrez Zelaya Alyson Sabrina Vazquez Ashleigh Ogg Rajesh Prabhu Balaraman Hyuk Cho Madhusudan Choudhary Department of Biological Sciences Sam Houston State University Huntsville Texas USA Department of Computer Science Sam Houston State University Huntsville Texas USA

The term “microgravity” is used to describe the “weightlessness” or “zero-g” circumstances that can only be found in space beyond earth’s atmosphere. Rhodobacter sphaeroides is a gram-negative purple phototroph, used as a model organism for this study due to its genomic complexity and metabolic versatility. Its genome has been completely sequenced, and profiles of the differential gene expression under aerobic, semi-aerobic, and photosynthetic conditions were examined. In this study, we hypothesized that R. sphaeroides will show altered growth characteristics, morphological properties, and gene expression patterns when grown under simulated microgravity. To test that, we measured the optical density and colony-forming units of cell cultures grown under both microgravity and normal gravity conditions. Differences in the cell morphology were observed using scanning electron microscopy (SEM) images by measuring the length and the surface area of the cells under both conditions. Furthermore, we also identified homologous genes of R. spheroides using the differential gene expression study of Acidovorax under microgravity in our laboratory. Growth kinetics results showed that R. sphaeroides cells grown under microgravity experience a shorter log phase and early stationary phase compared to the cells growing under normal gravity conditions. The length and surface area of the cells under microgravity were significantly higher confirming that bacterial cells experience altered morphological features when grown under microgravity conditions. Differentially expressed homologous gene analysis indicated that genes coding for several COG and GO functions, such as metabolism, signal-transduction, transcription, translation, chemotaxis, and cell motility are differentially expressed to adapt and survive microgravity.

关键词： Simulated Microgravity Differential Gene Expression Bacteria Gene Homology Space Exploration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

DFT Studies of Electronic Properties and Effect of He and Xe Incorporation in Selected Ceramics

引用

Journal of Modern Physics 2024年第10期15卷 1485-1501页

作者： Barbara Szpunar Jayangani I. ranasinghe Jerzy A. Szpunar Department of Physics and Engineering Physics University of Saskatchewan Saskatoon Canada Department of Mechanical Engineering University of Saskatchewan Saskatoon Canada

The electronic properties of several prospective nuclear fuels are not yet well known. We used Quantum Espresso and EPW codes to evaluate the electron density of states, the electronic heat capacity coefficient, the electron-phonon coupling strength, the number of mobility electrons, and the electronic heat conductivity. The electronic properties for ThN, ThC and UN using a slightly different approach that were previously evaluated are discussed and the results are compared. We confirmed that while the electronic heat capacity coefficient is linearly dependent on the electron density of states at Fermi energy, such a simple relation could not be used to determine the difference in the electronic heat conductivity of investigated materials. The highest heat conductivity was registered in ThN. These metallic fuels also have high U/Th density, therefore are more economical since enrichment is expensive. Furthermore, it is important to examine swelling in these high-density fuels. We evaluated that UN had 42% more U atoms per unit volume than UO2 and a 55% higher volume increase when accommodating one Xe atom in one interstitial of a (2 × 2 × 2) supercell. However, for He, the volume increase was 27% lower in UN. Interestingly, even though the Th atom’s density in ThN and ThC was lower than that of U atoms in the UN compound, a similar trend of volume changes was found. We concluded, therefore, that when we consider swelling, the local structural symmetry (tetrahedral versus octahedral sites) is more important than the density of atoms. The 37 % greater of absolute value of the total energy increase due to incorporation of Xe in ThC versus ThN cannot be explained by the crystal structure since a ThC-Xe supercell has a higher lattice constant than a ThN-Xe corresponding supercell. Such results can only be explained by investigating electronic structure.

关键词： UN ThN ThC Thermal Conductivity Defects

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An assessment on the test setups used for energy labeling of ceiling fans

引用

Building Simulation 2021年第4期14卷 1175-1188页

作者： Dilshan Ramesh Casseer Chathura ranasinghe Department of Mechanical Engineering University of MoratuwaMoratuwaSri Lanka

Ceiling fans are used all over the world as a mean of enhancing indoor thermal comfort. A number of grading programs have been initiated for assessing energy performance of ceiling fans, such as ANSI/AMCA 230, Energy Star, IEC 60879, IS 374 and SLS 1600. The configurations of test setups used for performance evaluations in these standards have significant differences to each other. In this study, the influence of such differences on the calculated performance grade of ceiling fans were investigated and the suitability of each dimension of the test set-up is discussed. Particular emphasis was placed on quantifying the effect of the cylindrical drum used in Energy Star and SLS test methods. For this assessment, extensive three-dimensional numerical simulations and experimental measurements were used. Accordingly, the effect of cylinder height, gap between the fan rotation plane and the cylinder, cylinder diameter and the dimensions of the test chamber were investigated. Results show that, the test cylinder, has no significant impact on the calculated performance grade of the tested ceiling fan (variation is less than 2%), and may be eliminated from the test setup. This justifies the recent decision of AMCA on the removal of test cylinder from the fan test set-up. Further, it was also found that the set up dimensions considered herein is large enough so that the calculated start rating is uneffaced by the surrounding solid walls.

关键词： ceiling fans energy label Energy Star test standards efficiency

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Diversity and species composition of microbiota associated with dengue mosquito breeding habitats:A cross-sectional study from selected areas in Udapalatha MOH division,Sri Lanka

引用

Asian Pacific Journal of Tropical Medicine 2023年第8期16卷 363-370页

作者： Yashoda Kumari Deepika Amarasinghe Koshila ranasinghe Department of Zoology and Environmental Management Faculty of ScienceUniversity of KelaniyaDalugamaKelaniya GQ 11600Sri Lanka

Objective:To determine the diversity of microbiota associated with different breeding habitats of dengue vector mosquitoes Aedes(Ae.)aegypti and *** and to identify any parasitic,epibiont,pathogenic,competitive or predatory ***:Sampling was performed from a variety of breeding habitats using dipping,pipetting and siphoning *** in water samples were preserved using Rose Bengal solution and Lugol's iodine,and were *** samples of microbiota were kept under laboratory conditions to observe any pathogenic or parasitic microbiota interacting with ***:A total of eleven microbiota species(Canthocamptus staphylinus,Canthocamptus microstaphylinus,Parastenocaris brevipes,Lepadella ovalis,Lepadella patella,Rotatoria rotatoria,Rotatoria macrura,Asplanchna brightwelli,Trichocerca rattus,Euglena variabilis,and Flagilaria capucina)belonging to four(4)phyla(Arthropoda,Rotifera,Euglenozoa,and Ochrophyta)and 8 microbiota species belonged to four phyla(Arthropoda,Rotifera,Euglenozoa,and Ochrophyta)were identified from *** and *** breeding habitats *** was a higher percentage(54.54%)of larval habitats positive for the secondary vector *** than through the primary vector *** in the Gampola urban area indicating higher possibility of transmitting the dengue virus through the secondary ***,no pathogenic or parasitic ciliates on mosquito larvae were encountered in the present *** findings may be due to sampling maingly from temporary container-type breeding ***:The relative distribution of microbiota associated with mosquito species differed significantly among *** and *** overall findings of this study could help in implementing novel eco-friendly vector-control strategies in the study area.

关键词： Aedes Biological Mosquito-control Vectors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The effect of biochar on mycorrhizal fungi mediated nutrient uptake by coconut(Cocos nucifera L.)seedlings grown on a Sandy Regosol

引用

Biochar 2022年第1期4卷 56-73页

作者： Gertrude Scynthya Nirukshan Sanathanie ranasinghe Steven Sleutel Department of Environment Ghent UniversityCoupure Links 6539000 GhentBelgium. Coconut Research Institute Lunuwila 61150Sri Lanka

Biochar amendment of soil may ameliorate inherently infertile soils,such as in the typical coconut(Cocos nucifera L.)growth areas along tropical coasts,where,moreover,temporary moisture stress commonly *** conducted a pot experiment to evaluate the effects of biochar soil amendment(1%w/w)produced from Gliricidia sepium stems(BC-Gly)and rice husks(BC-RiH)on the growth of coconut seedlings and on N and P uptake mediated by mycorrhizae under wet or dry conditions in a Sandy *** pots were divided into root and hyphal zones by a nylon mesh,where 15N labelled N and P nutrients were only provided in the hyphal *** wet conditions,biochar applica-tion did not affect plant growth,while under dry conditions,the BC-Gly increased root and plant growth similar to that under wet ***-Gly increased the acidic pH of the soil to a neutral level,and the microbial community shifted towards a higher fungal *** P accumulated(Pacc)in roots was higher with BC-Gly and BC-RiH under dry and wet conditions,*** weakly correlated with the abundance of arbuscular mycorrhizal fungi(AMF)in the hyphal *** BC-Gly roots showed lower N derived from *** conclude that biochar application has no impact on crop growth under wet conditions,while under dry conditions,BC-Gly stimulates crop growth and P uptake,probably through liming induced P availability but also possibly by some enhancement of AMF *** shift in the fungal-oriented microbial community and reduced plant fertilizer N uptake suggested that BC-Gly acted as an additional N source.

关键词： Coconut growing soil 15N isotope labelling Root-exclusion study container Phosphorus Moisture stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Monsoonal impact on circulation pathways in the Indian Ocean

引用

Acta Oceanologica Sinica 2020年第3期39卷 103-112页

作者： Sinhalage Udaya Priyantha Jinadasa Gayan Pathirana Pradeep Nalaka ranasinghe Luca Centurioni Verena Hormann Department of Oceanography The Ocean University of Sri LankaCrow IslandColombo 01500Sri Lanka National Institute of Oceanography and Marine Sciences National Aquatic Resources Research and Development AgencyColombo 01500Sri Lanka Department of Oceanography and Marine Geology University of RuhunaMatara 81000Sri Lanka Scripps Institution of Oceanography UC San Diego 950092093-0213USA

Monsoon driven water mass exchange between the Bay of Bengal(Bo B) and Arabian Sea(AS) is the common experience. However, it is not yet firmly confirmed that the exchange pathway is either passing through southern tip of Sri Lanka or Palk Strait. Local circulation patterns impact the pathways followed by the East Indian Coastal Currents(EICC) that drive exchange, thereby modulating mixing and water mass transformation in the Bay of Bengal around Sri Lanka. In this study, observations from surface drifters were incorporated with the satellite derived data to understand the monsoonal impact on circulation patterns in the Indian Ocean. This was the first multi-national scientific effort which was conducted in the Bo B and AS during 2013 to 2015 to understand the monsoonal impact on circulation patterns in the complex region. The results indicated that seasonally reversing monsoonal currents of southern Sri Lanka, traced by the wintertime freshwater export pathways of the EICC. The deflection of monsoon currents running along the east coast of Sri Lanka by forming cyclonic and anti-cyclonic eddies, which influence the mixing and stirring associated with these flows. Results further indicate the low salinity cold water flows from the Bo B to AS along the western boundary of the Bo B during northeast monsoon. In the same way, reverses the phenomena during southwest monsoon, transporting high salinity warm water from AS to the Bo B. This maintain the bay status which occurred due to freshwater influx from large rivers and high saline water from AS. However, no evidences were observed for the exchange through Palk Strait during the ***, there are some mis-matches in in-situ and remotely sensed measurements which imply the necessity of systematic observation system for the complex region as an alternative approach.

关键词： Bay of Bengal northeast monsoon southwest monsoon circulation surface drifters

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prediction of the effectiveness of rolling dynamic compaction using artificial neural networks and cone penetration test data

引用

岩石力学与工程学报 2019年第1期38卷 153-170页

作者： R.A.T.M.ranasinghe M.B.Jaksa F.Pooya Nejad Y.L.Kuo School of Civil Environmental and Mining EngineeringUniversity of Adelaide

Rolling Dynamic Compaction(RDC),which is a ground improvement technique involving non-circular modules drawn behind a tractor,has provided the construction industry with an improved ground compaction capability,especially with respect to a greater influence depth and a higher speed of compaction,resulting in increased productivity. However,to date,there is no reliable method to predict the effectiveness of RDC in a range of ground conditions. This paper presents a new and unique predictive tool developed by means of artificial neural networks(ANNs) that permits a priori prediction of density improvement resulting from a range of ground improvement projects that employed 4-sided RDC modules;commercially known as"impact rollers". The strong coefficient of correlation(i.e. R>0.86) and the parametric behavior achieved in this study indicate that the model is successful in providing reliable predictions of the effectiveness of RDC in various ground conditions.

关键词： soil mechanics rolling dynamic compaction artificial neural networks cone penetration test ground improvement

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prediction of chemical composition for callus production in Gyrinops walla Gaetner through machine learning

引用

Information Processing in Agriculture 2020年第4期7卷 511-522页

作者： Sachithri P.Munasinghe Seneviratnege Somaratne Shyama R.Weerakoon Chandani ranasinghe Department of Botany The Open University of Sri LankaP.O.Box 21NawalaNugegoda 10250Sri Lanka Department of Chemistry The Open University of Sri LankaP.O.Box 21NawalaNugegoda 10250Sri Lanka

Developing new tissue culture protocols and optimization of plant media composition for particular plant species are precluded by the higher labor,time and *** usage of machine learning becomes rewarding tools for efficient,cost-effective method of optimization of growth media composition for desires growth *** are often encountered in determination of media composition for raising calli from explants of woody Gyrinops *** paper provides the finding of the study performed on modeling and optimization of chemical composition of culture media for raising callus from explants of *** of experiments were conducted to raise calli from sterilized leaf and node explants with varying concentrations of 1-Naphthaleneacetic acid(NAA),6-Benzylaminopurine(BAP)and coconut water in Murashige and Skoog medium(MSM)and Woody plant medium(WPM)were *** Neural Networks(ANNs)were developed to predict the best media composition on callus weight(CW),callus induction percentage(CIP)and days taken to initiate callus(DC).Callus formation was observed in all the experiments except for *** ANN models were developed to predict the best media composition for CW,CIP and *** results of ANN models predict optimum media composition during the training,validation and testing with satisfactory levels of *** R2 values of the best ANN models;CWnet,CIPnet and DCnet were 0.95,0.95 and 0.88 *** mean sums of square errors(RMSRs)of CWnet,CIPnet and DCnet were 0.1410,0.1391 and 0.1961 and mean residual(MRs)were 0.0199,0.0194 and *** corrected Akaike information criterion(AICc)of the models was331.431,254.926 and210.777,and Schwarz Bayesian information criterion(SBC)were490.495,454.229 and*** predicted best media consisting MSM+3.0 mg/l NAA+0.5 mg/l BAP and MSM+1.5 mg/l NAA+0.5 mg/l BAP were the optimum combination for leaves and nodal explants *** AICc and SBC of CWnet indicated

关键词： Gyrinops walla Gaetner Tissue culture Coconut water Woody plant Artificial neural network

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Visualizing the spatial water quality of Bentota, Sri Lanka in the presence of seawater intrusion

引用

Journal of Groundwater Science and Engineering 2019年第4期7卷 340-353页

作者： T K G P ranasinghe R U K Piyadasa Department of Town and Country Planning University of MoratuwaKatubaddaMoratuwa 10400Sri Lanka Department of Geography University of ColomboKumaratunga Munidasa MawathaColombo 00700Sri Lanka

Seawater flows towards the inlands along with the rivers and canals, through the process of infiltration and leaks in the ground water characterized by high concentrations of soluble salts. High salinity concentrations can make groundwater unsuitable for public consumption and surface water unsuitable for irrigation and agricultural activities. This study envisages the fluctuations of ground and surface water quality of Bentota area in the presence of seawater intrusion. The temporal and spatial variations of eleven water parameters were monitored by collecting the water samples during one year period. Spatial distributions were assessed by applying the Inverse distance weighted (IDW) interpolation method in Arc GIS 10.5 software. Water quality is assessed on the integration of all parameters in terms of an index based on the World Health Organization (WHO) standards. The significant linear relationship between the considered parameters of surface water (SW) and groundwater (GW) were identified applying correlation analysis using SPSS software. All parameters of surface water were above the permissible limits of WHO standards. Surface water quality index values with respect to 60% of canals show very poor quality (>1 250) of surface water indicating their unsuitability for irrigation activities. Those surface water bodies indicated very highly saline conditions during dry months. The spatial distribution of ground water quality index with respect to the highest parameter values of each sampling location indicates that 52.2% of total land extent of Bentota Divisional Secretariat Division (DSD) has good quality of ground water which is suitable for drinking. Its 47.2% of total land extent has poor quality of ground water for drinking purpose and less than 0.5% of the area consists of excellent or very poor quality of ground water in each. This study helps to manage coastal aquifers by understanding the extreme water quality conditions and coastal salinity.

关键词： Salt water intrusion Coastal salinity Water quality Spatial distribution

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of artificial neural networks for predicting the impact of rolling dynamic compaction using dynamic cone penetrometer test results

引用

Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 340-349页

作者： R.A.T.M. ranasinghe M.B. Jaksa Y.L. Kuo F. Pooya Nejad School of Civil Environmental and Mining EngineeringUniversity of AdelaideAdelaideAustralia

Rolling dynamic compaction(RDC),which involves the towing of a noncircular module,is now widespread and accepted among many other soil compaction ***,to date,there is no accurate method for reliable prediction of the densification of soil and the extent of ground improvement by means of *** study presents the application of artificial neural networks(ANNs) for a priori prediction of the effectiveness of *** models are trained with in situ dynamic cone penetration(DCP) test data obtained from previous civil projects associated with the 4-sided impact *** predictions from the ANN models are in good agreement with the measured field data,as indicated by the model correlation coefficient of approximately *** is concluded that the ANN models developed in this study can be successfully employed to provide more accurate prediction of the performance of the RDC on a range of soil types.

关键词： Rolling dynamic compaction(RDC) Ground improvement Artificial neural network(ANN) Dynamic cone penetration(DCP) test

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：