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Assessing dominant factors affecting soil erosion using a portable rainfall simulator

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International journal of Sediment Research 2008年第4期23卷 376-386页

作者： j.VAHABI d.NIKKAMI Soil Conservation and Watershed Management Research Institute

Investigating the causes of soil erosion is difficult in natural conditions owing to the presence of other factors. Without simplifying the experimental conditions, studying soil behavior with its numerous parameters while considering factors such as vegetation cover, topography, and rainfall is difficult and in most conditions impossible. The application of simulation approaches is therefore necessary to simplify the prototype. In this research, the effects of physical soil factors such as texture and antecedent soil moisture, along with land slope and vegetation cover were evaluated in the Taleghan watershed, Iran, using a rainfall simulator and soil erosion plots. For this purpose, a 89 × 120 cm rainfall simulator producing 24.5 and 32 mm/h rainfall intensities of 30 min duration, as a common condition of the study area, was used at 144 locations over soil erosion plots with dimensions of 95 × 125 cm. Plots had slope classes of 12–20 and 20–30 %, different soil textures, different antecedent soil moistures, and medium to poor vegetation cover conditions. It was found that for 24.5 and 32 mm/h rainfall intensities, the sediment yield had high correlations of –0.771 and –0.796 with vegetation cover and slight correlations of 0.045 and 0.029 with land slope respectively. Regression equations for predicting the sediment yield were also developed for different conditions.

关键词： Rainfall simulator Soil erosion Soil physical parameters Vegetation cover Taleghan watershed Iran

Occurrence,leaching,and mobility of major and trace elements in a coal mining waste dump:The case of douro Coalfield,Portugal

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Energy Geoscience 2021年第2期2卷 121-128页

作者： j.Ribeiro d.Flores department of Earth Sciences University of CoimbraRua Silvio Lima3030-790CoimbraPortugal Institute of Earth Sciences-Porto Pole Rua Do Campo Alegre 6874169-007PortoPortugal Environment and Spatial Planning Department of GeosciencesUniversity of PortoRua Do Campo Alegre 6874169-007PortoPortugal

The coal mining residues from past mining activities in the douro Coalfield are emplaced in many dumps near the mining areas,causing substantial environmental *** study aims to contribute to the investigation of environmental impacts caused by the disposal of the residue in the douro Coalfield through the determination of the geochemical composition of waste materials collected at 3 e 15 m depth,and of the water-leachable fraction produced by percolation in these materials inside the *** elements with higher concentration in the leachates are Ca,Cd,Co,Mg,Mn,Na,Ni,S,and Zn,indicating that they are the most easily leached and accessible elements for percolation and mobilization into the *** presence of these elements in the leachates is principally attributed to their occurrence as water-soluble ions in clays and sulphides affected by natural weathering conditions,which promotes their breakdown and occurrence as exchangeable *** leachates are classified as acid *** weathering and leaching in the Sao Pedro da Cova waste dump are the principal~paths for chemical elements to be percolated and mobilized to environment,posing risk to the soils,waters and ecosystems in the surrounding areas.

关键词： Coal mining Waste dump Water-soluble compound Hazardous element

Enhanced fitness due to higher fecundity,increased defence against a specialist and tolerance towards a generalist herbivore in an invasive annual plant

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journal of Plant Ecology 2009年第2期2卷 77-86页

作者： d.Abhilasha j.joshi Institute of Environmental Sciences University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Institute of Biochemistry and Biology Biodiversity Research/BotanyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany

Aims The superior performance of many non-indigenous species in a new range can be attributed to different factors such as pre-adaptation to environmental conditions in new areas or to factors inherent to displacement mechanisms such as loss of co-evolved pathogens and herbivores that increase the speed of evolutionary change towards a shift in allocation from defence to growth and *** assess the importance of the different mechanisms governing the success of Conyza canadensis,a globally successful invader,we simultaneously tested several recent hypotheses potentially explaining the factors leading to biological *** We tested(i)whether plants from the non-native range showed a higher fitness than plants from the native North American range,(ii)whether they differed in resistance against an invasive generalist herbivore,the slug Arion lusitanicus and against a recently established specialist aphid herbivore,Uroleucon erigeronense and(iii)experimentally assessed whether *** releases allelopathic chemicals that have harmful effects on competing species in the nonnative *** compared populations along a similar latitudinal gradient both in the native North American and invasive European range and analysed patterns of adaptive clinal variation in biomass *** Findings The invasion success of *** in Europe cannot be attributed to a single trait,but to a combination of *** plants benefited from increased growth and above all,increased reproduction(a key trait in an annual plant)and were less attacked by a co-migrated specialist *** observed loss of defence against generalist slugs did not translate into a decreased fitness as invasive *** plants showed a high re-growth *** contrast to earlier in vitro studies,we detected no allelopathic effects on the competing flora in the non-native *** latitudinal cline in vegetative biomass production in the non-native range observ

关键词： allelopathy biological invasions Conyza canadensis EICA hypothesis generalist/specialist herbivory latitudinal clines biogeographic comparison common garden

Association between water related factors and active trachoma in Hai district, Northern Tanzania

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Infectious diseases of Poverty 2012年第1期1卷 92-98页

作者： Michael j Mahande Humphrey d Mazigo Eliningaya j Kweka Community Health department KCM College of Tumaini UniversityPO Box 2240MoshiTanzania department of Medical Parasitology and Entomology Catholic University of Health and Allied SciencesP.O.Box 1464MwanzaTanzania Tropical Pesticides Research Institute Division of Livestock and Human Disease vector controlPO Box 3024ArushaTanzania

Background:Trachoma is widely distributed in sub-Saharan Africa and is mainly associated with poor water ***,these associations have never been demonstrated in some of the communities,especially in northern *** cover that gap,the present case control study was conducted to assess the association of water related factors,general hygiene and active trachoma among preschool and school age children in Hai district,northern ***:Families reported to use>60 litres of water per day were less likely to have active disease(OR=0.4,95%CI:0.1-0.3;Pd to households collecting≤60 *** risk of having trachoma increased with increase in distance to the water point(OR=6.5,95%CI;1.8-16.7;P=0.003).Households members who reported to used number of preschool children in the household was also associated with increased risk of active trachoma by 2.46 ***:Improving water supply near the households and providing public health education focusing on improving households socio-economic status and individual hygiene especially in pre-school children in part will help to reduce the prevalence of the *** addition,integrating public health education with other interventions such as medical interventions remains important.

关键词： Trachoma Water Hygiene Tanzania

Azoospermia:vasal agenesis

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Asian journal of Andrology 2022年第1期24卷 1-4页

作者： j Sam Fisher Edward d Kim department of Urology University of TennesseeKnoxvilleTN 37920USA

SPECIFIC GENETIC TESTS(CFTR ANd INTRON 8 SPLICE VARIANT TESTING)ANd THEIR SIGNIFICANCE Congenital bilateral absence of the vas deferens(CBAVd)and cystic fibrosis(CF)began as separate entities with an apparent clinical *** occurs in 1%–2%of men presenting with infertility at urological departments and has an incidence of 1:1000–1:2000 in Caucasian *** example of this anatomic variant is shown in Figure 1.

关键词： correlation. clinical Figure

Protein profiles of enzymatically isolated rumen epithelium in sheep fed a fibrous diet

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journal of Animal Science and Biotechnology 2019年第2期10卷 449-462页

作者： j.j.Bond A.j.donaldson j.V.F.Coumans K.Austin d.Ebert d.Wheeler V.H.Oddy NSW department of Primary Industries Extensive Livestock Industry CentreUniversity of New EnglandTrevenna RdArmidaleNSW 2351Australia School of Rural Medicine University of New EnglandArmidaleNSW 2351Australia NSW department of Primary Industries Orange Agricultural InstituteOrangeNSW 2800Australia.

Background: The rumen wall plays a major role in efficient transfer of digested nutrients in the rumen to peripheral tissues through the portal venous system. Some of these substrates are metabolised in the epithelium during this process. To identify the specific proteins involved in these processes, we used proteomic technologies. Protein extracts were prepared from ventral rumen tissue of six sheep fed a fibrous diet at 1.5× maintenance energy *** a newly developed method, we were able to enzymatically isolate the epithelial cells from underlying tissue layers, thus allowing cytosol and membrane fractions to be independently analysed using liquid chromatography tandem mass spectrometry(LC MS/MS).Results: Using our procedure we identified 570 epithelial proteins in the Ovis aries sequence database. Subcellular locations were largely cytosolic(n = 221) and extracellular(n = 85). However, a quarter of the proteins identified were assigned to the plasma membrane or organelle membranes, some of which transport nutrients and metabolites. Of these 91 were transmembrane proteins(TMHMM), 27 had an N-terminal signal peptide(signalP) and TMHMM motif,13 had a glycosylphosphatidylinositol(GPI) anchor and signalP sequence, 67 had beta(β) strands or 17 β strands and a transit peptide sequence, indicating the identified proteins were integral or peripheral membrane proteins. Subunits of the 5 protein complexes involved in mitochondrial cellular energy production were well represented. Structural proteins(15%), proteins involved in the metabolism of lipids and proteins(26%) and those with steroid or cytokine action were a feature of the ***: Our research has developed a procedure to isolate rumen epithelium proteins from the underlying tissue layers so that they may be profiled using proteomic technologies. The approach improves the number of proteins that can be profiled that are specific to the epithelium of the rumen wall. It provides new insights

关键词： Epithelium Metabolism Nutrition Proteome Rumen Sheep

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Effect of substituents in hydroxyl radical-mediated degradation of azo pyridone dyes: Theoretical approaches on the reaction mechanism

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journal of Environmental Sciences 2020年第12期32卷 14-21页

作者： j.dostanic M.Hus d.Loncarevic Institute of Chemistry Technology and MetallurgyUniversity of Belgrade(National Institute)Department of Catalysis and Chemical EngineeringNjegoševa 12BelgradeRepublic of Serbia department of Catalysis and Chemical Reaction Engineering National Institute of ChemistryHajdrihova 19LjubljanaSlovenia

Understanding the degradation behavior of azo dyes in photocatalytic wastewater treatment is of fundamental and practical importance for their application in textile-processing and other coloration industries. In this study, quantum chemistry, as density functional theory, was used to elucidate different degradation pathways of azo pyridone dyes in a hydroxyl radical(HO ·)-initiated photocatalytic system. A series of substituted azo pyridone dyes were synthesized by changing the substituent group in the para position of the benzene moiety, ranging from strong electron-donating to strong electron-withdrawing groups. The effect of dye molecular structure on the photocatalytic degradation reaction mechanism was analyzed and quantification of substituent effects on the thermodynamic and kinetics parameters was performed. Potential energy surface analysis revealed the most susceptible reaction site for the HO ·attack. The calculated reaction barriers are found to be strongly affected by the nature of substituent group with a good correlation using Hammett σp constants and experimentally determined reaction rates. The stability of pre-reaction complexes and transition state complexes were analyzed applying the distortion-interaction model. The increased stability of the transition state complexes with the distancing from the substituent group has been established.

关键词： Quantum chemical calculation density functional theory Azo dye Reaction mechanism Photocatalytic degradation Hydroxyl radical Hammett equation Substituent effect

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Predicting the performance of magnetocaloric systems using machine learning regressors

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Energy and AI 2020年第2期2卷 116-124页

作者： d.j.Silva j.Ventura j.P.Araujo IFIMUP-Institute of Physics for Advanced Materials Nanotechnology and PhotonicsFaculty of Science of the Porto UniversityPorto 4169-007Portugal

Since refrigeration,air-conditioning and heat pump systems account to 25–30%of all energy consumed in the world,there is a considerable potential to mitigate the Global Warming by increasing the efficiency of the related *** systems,*** and heat pumps,are promising solutions due to their large theoretical Coefficient Of Performance(COP).However,there is still a long way to make such systems *** barrier is the cost of the magnet and magnetocaloric materials,which can be overcome by decreasing the materials quantity,*** optimizing the geometry with efficient dimensioning *** this work,we have developed a machine learning method to predict the three most significant performance values of magnetocaloric heat pumps:temperature span,heating power and *** used 4 different regressors:ordinary least squares,ridge,lasso and K-Nearest Neighbors(KNN).By using a dataset generated by numerical calculations,we have arrived at minimum average relative errors of the temperature span,heating power and COP of 23%,29%and 31%,*** the lasso regressor is more appropriate when using small datasets,the ordinary least squares regressor shows the best performance when using more *** best order of polynomials range between 3,for the heating power,to 5,for the *** worse performance in predicting the three performance values occurs when using the KNN ***,the application of regressors to the dataset is more adequate to evaluate the temperature span rather than energetic performance values.

关键词： Magnetic refrigeration Active magnetic regeneration Magnetocaloric effect Regressors

dietary zinc and metallothionein on small intestinal disaccharidases activity in mice

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World journal of Gastroenterology 2011年第3期17卷 354-360页

作者： Cuong d Tran johanna Cool Cory j Xian Gastroenterology Unit ChildrenYouth and Women's Health Service discipline of Physiology School of Medical SciencesThe University of Adelaide discipline of Agricultural and Animal Science School of AgricultureFood and Wine The University of Adelaide Adelaide Sansom Institute for Health Research School of Pharmacy and Medical SciencesUniversity of South Australia

AIM: To examine the effect of increasing dietary zinc (Zn) intake and the lack of metallothionein (MT) expression on activity of small intestinal disaccharidases. METHOdS: MT-Ⅰ and Ⅱ knockout (MT-/-) and wild-type (MT+/+) female mice at 3.5 wk of age were randomly fed with a diet containing 2 (2 Zn), 15 (15 Zn) or 50 (50 Zn) mg Zn/kg (n = 8/group/genotype) for 5 wk. Small intestinal segments (duodenum, jejunum and ileum) were collected and either fixed in 10% formalin for histological analysis or snap frozen in liquid nitrogen for sucrase, lactase and maltase activity ***: Plasma Zn was significantly (P d with MT+/+ mice fed the 2 Zn diet. Villus height and crypt depth were increased by approximately 15% in MT+/+ mice compared with MT-/- mice. duodenal disaccharidase activities were significantly higher in MT+/+ compared with MT-/- mice particularly in those fed the 2 Zn diet. For the 50 Zn diet, jejunal sucrase and lactase activities were significantly higher in MT-/- (13 313 ± 2314; 4107 ± 364 μmol glucose/well/min/g tissue, respectively) compared with MT+/+ mice (7054 ± 608; 1818 ± 174). Similarly, ileal lactase activities were higher in MT-/- (1480 ± 192) compared with MT+/+ (629 ± 353) mice particularly those fed the 2 Zn diet. CONCLUSION: Increasing dietary Zn has little effect on disaccharidases activity in MT wild-type mice. The presence of MT may enhance morphological and functional development of the gut.

关键词： Lactase Maltase Sucrase Metallothionein diet Zinc