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Distributed Modeling of Extraterrestrial Solar Radiation Over the Rugged Terrains of Pakistan

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Journal of Mountain Science 2011年第3期8卷 427-436页

作者： romana AMBREEN QIU Xinfa Iftikhar AHMAD Key laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science & Technology Nanjing 210044 China Department of Geography University of Balochistan Quetta Pakistan

In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least *** density of stations and their spatial coverage particularly in difficult peripheral national territories,little or no solar radiation data,non-satisfactory sunshine hours data,and low quality of ground observed cloud cover data create a situation in which the spatial modeling of Extraterrestrial Solar Radiation(ESR) and its ground parameterization got sufficient *** Digital Elevation Model (DEM) input into Geographic Information System (GIS) is a compatible tool to demonstrate the spatial distribution of ESR over the rugged terrains of the study *** the first time,distributed modeling of ESR is done over the rugged terrains of Pakistan,based on DEM and ArcGIS..Results clearly depict that the complex landforms profoundly disrupt the zonal distribution of ESR in *** screening impact of topography is higher on spatial distribution of ESR in winter and considerably low in *** combined effect of topography and latitude is ***,the model was further testified by plotting Rb (ratio of ESR quantity over rugged terrain against plane surface) against azimuth at different latitudes with different angled *** results clearly support the strong screening effect of rugged terrain through out the country especially in Himalayas,Karakoram and Hindukush (HKH),western border mountains and Balochistan *** model can be instrumental as baseline geospatial information for scientific investigations in Pakistan,where substantial fraction of national population is living in mountainous regions.

关键词： Pakistan distributed modeling ESR DEM GIS rugged terrain

Subcellular Distribution of Glutathione Precursors in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第12期53卷 930-941页

作者： Barbara Eva Koffler romana Maier Bernd Zechmann University of Graz Institute of Plant Sciences 8010 Graz Austria Graz University of Technology Institute for Electron Microscopy and Fine Structure Research 8010 Graz Austria

Glutathione is an important antioxidant and has many important functions in plant development, growth and defense. Glutathione synthesis and degradation is highly compartment-specific and relies on the subcellular availability of its precursors, cysteine, glutamate, glycine and γ-glutamylcysteine especially in plastids and the cytosol which are considered as the main centers for glutathione synthesis. The availability of glutathione precursors within these cell compartments is therefore of great importance for successful plant development and defense. The aim of this study was to investigate the compartmentspecific importance of glutathione precursors in Arabidopsis thaliana. The subcellular distribution was compared between wild type plants （Col-0）, plants with impaired glutathione synthesis （glutathione deficient pad2-1 mutant, wild type plants treated with buthionine sulfoximine）, and one complemented line （OE3） with restored glutathione synthesis. Immunocytohistochemistry revealed that the inhibition of glutathione synthesis induced the accumulation of the glutathione precursors cysteine, glutamate and glycine in most cell compartments including plastids and the cytosol. A strong decrease could be observed in γ-glutamylcysteine （γ-EC） contents in these cell compartments. These experiments demonstrated that the inhibition of γ-glutamylcysteine synthetase （GSH1） - the first enzyme of glutathione synthesis - causes a reduction of γ-EC levels and an accumulation of all other glutathione precursors within the cells.

关键词： Arabidopsis cysteine glutamate glutathione glycine.

A new cluster validity index using maximum cluster spread based compactness measure

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International Journal of Intelligent Computing and Cybernetics 2016年第2期9卷 179-204页

作者： M.Arif Wani romana Riyaz Postgraduate Department of Computer Science University of KashmirSrinagarIndia

Purpose-The most commonly used approaches for cluster validation are based on indices but the majority of the existing cluster validity indices do not work well on data sets of different *** purpose of this paper is to propose a new cluster validity index(ARSD index)that works well on all types of data ***/methodology/approach-The authors introduce a new compactness measure that depicts the typical behaviour of a cluster where more points are located around the centre and lesser points towards the outer edge of the cluster.A novel penalty function is proposed for determining the distinctness measure of *** linear search-algorithm is employed to evaluate and compare the performance of the five commonly known validity indices and the proposed validity *** values of the six indices are computed for all nc ranging from(nc_(min),nc_(max))to obtain the optimal number of clusters present in a data *** data sets used in the experiments include shaped,Gaussian-like and real data ***-Through extensive experimental study,it is observed that the proposed validity index is found to be more consistent and reliable in indicating the correct number of clusters compared to other validity *** is experimentally demonstrated on 11 data sets where the proposed index has achieved better ***/value-The originality of the research paper includes proposing a novel cluster validity index which is used to determine the optimal number of clusters present in data sets of different complexities.

关键词： Clustering Cluster analysis Cluster validity Compactness measure Optimal number Distinctness measure

Effect of Particle Orientation on Heat Transfer in Arrays of Prolate Particles

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1509-1526页

作者： romana Basit Xinyang Li Zheqing Huang Qiang Zhou School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’anChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’anChina

Direct Numerical Simulations have been carried out to study the forced convection heat transfer of flow through fixed prolate particles for a variety of aspect ratios ar={5/4,5/3,5/1}with Reynolds number(Re)up to *** variations of the solid volume fraction c={0.1,0.2,0.3}with four Hermans orientation factors S={−0.5,0,0.5,1}are *** has been found that changes in S cause prominent variations in the Nusselt *** general,Nusselt number increases with the decrease of *** all three aspect ratios,the Nusselt number remains a linear function of S at different c and ***,it is concluded that,for heat transfer from prolate muti-particle system,the effects of orientations cannot be ignored.A new correlation for Nusselt number has been developed for arrays of prolate particles using the simulation data as a function of Re,c,S and ar.

关键词： Direct Numerical Simulation heat transfer lattice Boltzmann method particle orientations prolate particles

Bioactive lipids in cancer stem cells

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World Journal of Stem Cells 2019年第9期11卷 693-704页

作者： romana-Rea Begicevic Frank Arfuso Marco Falasca Metabolic Signalling Group School of Pharmacy and Biomedical SciencesCurtin Health Innovation Research InstituteCurtin UniversityPerthWA 6102Australia Stem Cell and Cancer Biology Laboratory School of Pharmacy and Biomedical SciencesCurtin Health Innovation Research InstituteCurtin UniversityPerthWA 6102Australia

Tumours are known to be a heterogeneous group of cells,which is why they are difficult to *** possible cause for this is the existence of slow-cycling cancer stem cells(CSCs)endowed with stem cell-like properties of self-renewal,which are responsible for resistance to chemotherapy and *** recent years,the role of lipid metabolism has garnered increasing attention in ***,the key roles of enzymes such as stearoyl-CoA desaturase-1 and 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase in CSCs,have gained particular ***,despite accumulating evidence on the role of proteins in controlling lipid metabolism,very little is known about the specific role played by lipid products in *** review highlights recent findings on the role of lipid metabolism in CSCs,focusing on the specific mechanism by which bioactive lipids regulate the fate of CSCs and their involvement in signal transduction pathways.

关键词： Cancer stem cells Lipid metabolism Bioactive lipids ABC transporters

Influence of environmental predispositions on temperate mountain forest damage at different spatial scales during alternating drought and flood periods:case study in Hruby Jeseník Mts.(Czech Republic)

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Journal of Mountain Science 2022年第7期19卷 1931-1944页

作者： Pavel SAMEC romana KUDELKOVA Petr LUKES Ales KUCERA Pavel CUDLIN Global Change Research Institute CAS Bělidla 986/4aBrnoCZ-60300Czech Republic Department of Geology and Soil Science Faculty of Forestry and Wood TechnologyMendel University in BrnoZemědělská3BRNOCZ-61300Czech Republic Department of Geoinformatics Faculty of SciencePalacky University Olomouc17.listopadu 50OlomoucCZ-77900Czech Republic

Mountain forests are more prone to environmental predispositions(EPs)than submountain *** remote sensing of mountain forests enables instantaneous damage mapping,the investigation of the causes requires field ***,a local field or regionally modeled environmental characteristics influence remote data evaluation *** study focused on the evaluation of EPs effects damaging mountain forests between various spatial resolutions during environmental *** evaluation was divided into managed and natural forests in the Hruby Jeseník Mts.(Czech Republic;240-1491 m a.s.l.;50.082°N,17.231°E).Damage was assessed through the discrimination analysis of the normalised difference vegetation index(NDVI)by MODIS VI during alternating drought and flood periods *** local environmental influence was assessed using the discrimination function(DF)separability of forest damage in the training *** regional influence was assessed through map algebra estimated via the DF and a forest decline spatial model based on EPs from differences between risk growth conditions and biomass fuzzy ***,EPs and soil influenced forest NDVI at different *** management afflicted the NDVI more than the *** EPs afflicted the NDVI more than the soil *** winters and droughts had a greater influence on the NDVI than the flood events,with the winter of 2005/2006 inverting the DF direction,and the 2003 drought increasing differences in managed forest biomass and decreasing differences in natural forest *** than 50% of declining managed forests in the training sets occurred on Leptosols,Podzols and *** a regional scale,the soil influence was eliminated by multiple *** EPs influenced 96% of natural forest and 65% of managed forest,though managed forest damage was more *** mountain forest NDVI decline was dependent on both management and risk predispositions.

关键词： Mountain environment Forest damage types Canopy density Soil group Norway spruce(Picea abies)

Gastrointestinal microbiota:A predictor of COVID-19 severity?

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World Journal of Gastroenterology 2022年第45期28卷 6328-6344页

作者： Maria Adriana Neag Damiana-Maria vulturar Diana Gherman Codrin-Constantin Burlacu Doina Adina Todea Anca Dana Buzoianu Department of Pharmacology Toxicology and Clinical PharmacologyIuliu Hațieganu University of Medicine and PharmacyCluj-Napoca 400337Romania Department of Pneumology Iuliu Hatieganu University of Medicine and PharmacyCluj-Napoca 400332Romania Department of Radiology Iuliu Hațieganu University of Medicine and PharmacyCluj-Napoca 400347Romania Iuliu Haţieganu University of Medicine and Pharmacy Cluj-Napoca 400347Romania

Coronavirus disease 2019(COVID-19),caused by a severe acute respiratory syndrome coronavirus 2 infection,has raised serious concerns worldwide over the past 3 *** severity and clinical course of COVID-19 depends on many factors(e.g.,associated comorbidities,age,etc)and may have various clinical and imaging findings,which raises management *** microbiota composition is known to influence respiratory disease,and respiratory viral infection can also influence gut *** and lung microbiota and their relationship(gut-lung axis)can act as modulators of *** the intestinal microbiota,by improving its composition and diversity through nutraceutical agents,can have a positive impact in the prophylaxis/treatment of COVID-19.

关键词： Gut microbiota COVID-19 Prognostic biomarkers Gut-lung axis Probiotics Nutraceuticals

The first cavefish in the Dinaric Karst?Cave colonization made possible by phenotypic plasticity in Telestes karsticus

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Zoological Research 2023年第4期44卷 821-833页

作者： MateoČupić Zoran Marčić Marko Lukić romana Gračan Helena Bilandžija Division of Molecular Biology Ruđer BoškovićInstituteZagreb 10000Croatia Department of Biology Faculty of ScienceZagreb 10000Croatia Croatian Biospeleological Society Zagreb 10000Croatia

Cave animals are an excellent model system for studying adaptive *** present,however,little is known about the mechanisms that enable surface colonizers to survive in the challenging environment of *** possibility is that these species have the necessary genetic background to respond with plastic changes to the pressures of underground *** gain insight into this process,we conducted a comparative study with the fish species Telestes karsticus,which occurs in a hydrological system consisting of an interconnected stream and a *** showed that *** resided year-round and spawned in Sušik cave,making it the first known cavefish in the Dinaric *** and surface populations differed in morphological and physiological characteristics,as well as in patterns of gene expression without any evidence of genetic *** test whether observed trait differences were plastic or genetic,we placed adult fish from both populations under light/dark or constant dark *** laboratory conditions erased all morphometric differences between the two morphs,suggesting phenotypic plasticity is driving the divergence of shape and size in wild *** pigmentation and increased fat deposition exhibited by cave individuals were also observed in surface fish kept in the dark in the *** study also revealed that specialized cave traits were not solely attributed to developmental plasticity,but also arose from adult responses,including ***,we conclude that *** can adapt to cave conditions,with phenotypic plasticity playing an important role in the process of cave colonization.

关键词： Maladaptive and adaptive phenotypic plasticity Troglobionts and stygobionts Endemic leuciscid fish Acclimatization European cavefish Cave adaptations Gene expression differences

Latitudinal gradients of biodiversity and ecosystem services in protected and non-protected oak forest areas can inform climate smart conservation

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Geography and Sustainability 2024年第4期5卷 647-659页

作者： Anders Forsman Johanna Sunde romana Salis Markus Franzen Department of Biology and Environmental Science Linnaeus UniversitySE-39182KalmarSweden Department of Physics Chemistry and Biology(IFM)Linköing UniversitySE-58183LinköingSweden

Adaptive governance of areas set aside for future protection of biodiversity,sustainable production,and recreation requires knowledge about whether and how effects of area protection are modulated by climate change and redistribution of *** investigate this,we compare biodiversity of plants(assessed using vegetation plots)and arthropods(collected with Malaise traps,analyzed using metabarcoding)and productivity(tree growth,determined using dendrochronology)in protected and non-protected oak(Quercus spp.)forests along a latitudinal gradient(55.6°N–60.8°N)in *** also compare historical,recent and projected future climate in the *** contrast to established global latitudinal diversity gradients,species richness of plants and arthropods increased northwards,possibly reflecting recent climate-induced community redistributions,but neither was higher in protected than in non-protected areas,nor associated with contemporary ground *** composition of arthropods also did not differ between protected and non-protected *** biomass increased with latitude,suggesting that the magnitude of cascading effects mediated via their roles as pollinators,herbivores,and prey for other trophic levels,varies geographically and will change with a moving *** growth rate of oaks(an ecosystem service in the form of biomass increase and carbon sequestration)was independent of latitude and did not differ between protected and non-protected *** findings question the efficacy of contemporary designation and management of protected oak forests,and emphasize that development and implementation of modified climate smart conservation strategies is needed to safeguard ecosystem functioning,biodiversity,and recreational values of protected forest areas against future challenges.

关键词： Biological diversity Conservation biology Decision making Forest ecosystems Global warming Species-richness gradients