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Influence of experimental soil disturbances on the diversity of plants in agricultural grasslands

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Journal of Plant Ecology 2014年第6期7卷 509-517页

作者： Jörg Müller Johannes heinze Jasmin Joshi Steffen Boch Valentin h.Klaus Markus Fischer daniel Prati Institute of Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany Freie Universität Berlin Institut für BiologieBerlin-Brandenburg Institute of Advanced Biodiversity ResearchAltensteinstrasse 614195 BerlinGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Institute of Landscape Ecology University of MünsterHeisenbergstr.248149 MünsterGermany Biodiversity and Climate Research Centre BIK-F Senckenberg Gesellschaft für Naturforschung603257 FrankfurtGermany

Aims and Methods Disturbance is supposed to play an important role for biodiversity and ecosystem stability as described by the intermediate disturbance hypoth-esis(IDh),which predicts highest species richness at intermediate levels of *** this study,we tested the effects of artificial soil distur-bances on diversity of annual and perennial vascular plants and bryo-phytes in a field experiment in 86 agricultural grasslands differing in land use in two regions of *** each grassland,we implemented four treatments:three treatments differing in application time of soil dis-turbances and one *** year after experimental disturbance,we recorded vegetation and measured biomass productivity and bare *** analysed the disturbance response taking effects of region and land-use-accompanied disturbance regimes into *** Findings Region and land-use type strongly determined plant species *** disturbances had small positive effects on the species richness of annuals,but none on perennials or *** ground was positively related to species richness of ***,exceeding the creation of 12%bare ground further distur-bance had a detrimental effect on bryophyte species richness,which corresponds to the *** biomass productivity was unaffected by disturbance our results indicate that the disturbance effect on spe-cies richness of annuals was not due to decreased overall produc-tivity,but rather due to short-term lowered inter-and intraspecific competition at the newly created ***,our results highlight the importance of soil disturbances for species richness of annual plants and bryophytes in agricultural ***,most grasslands were disturbed naturally or by land-use practices and our additional experimental soil dis-turbances only had a small short-term ***,total plant diversity in grasslands seemed to be more limited by the availabil-ity of propagules rather tha

关键词： annuals bryophytes colonization intermediate disturbance hypothesis microsites

Segmented thermoelectric generator modelling and optimization using artificial neural networks by iterative training

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能源与人工智能(英文) 2023年第2期12卷 76-85页

作者： Yuxiao Zhu daniel W.Newbrook Peng Dai Jian Liu C.h.Kees de Groot Ruomeng huang School of Electronics and Computer Science University of SouthamptonSouthamptonUnited Kingdom School of Physics Shandong UniversityShandongChina

Renewable energy technologies are central to emissions reduction and essential to achieve net-zero *** thermoelectric generators(STEG)facilitate more efficient thermal energy recovery over a large temperature ***,the additional design complexity has introduced challenges in the modelling and optimization of its *** this work,an artificial neural network(ANN)has been applied to build accurate and fast forward modelling of the *** importantly,we adopt an iterative method in the ANN training process to improve accuracy without increasing the dataset *** approach strengthens the proportion of the high-power performance in the STEG training *** increasing the size of the training dataset,the relative prediction error over high-power STEG designs decreases from 0.06 to 0.02,representing a threefold *** with a genetic algorithm,the trained artificial neural networks can perform design optimization within 10 s for each operating *** is over 5,000 times faster than the optimization performed by the conventional finite element *** an accurate and fast modeller also allows mapping of the STEG power against different *** modelling approach demonstrated in this work indicates its future application in designing and optimizing complex energy harvesting technologies.

关键词： Segmented thermoelectric generator Artificial neural network Genetic algorithm Optimization Iterative training

Therapeutic potential of α7 nicotinic receptor agonists to regulate neuroinflammation in neurodegenerative diseases

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Neural Regeneration Research 2017年第9期12卷 1418-1421页

作者： Laura Foucault-Fruchard daniel Antier UMR INSERM U930 Université Fran?ois Rabelais ChRU de Tours H?pital Bretonneau

Neurodegenerative diseases, such as Alzheimer＇s, Parkinson＇s and huntington＇s diseases, are all character- ized by a component of innate immunity called neuroinflammation. Neuronal loss and neuroinflammation are two phenomena closely linked. hence, the neuroinflammation is a relevant target for the management of the neurodegenerative diseases given that, to date, there is no treatment to stop neuronal loss. Several studies have investigated the potential effects of activators of alpha 7 nicotinic acetylcholine receptors in animal models of neurodegenerative diseases. These receptors are widely distributed in the central nervous system. After activation, they seem to mediate the cholinergic anti-inflammatory pathway in the brain. This anti-inflammatory pathway, first described in periphery, regulates activation of microglial cells considered as the resident macrophage population of the central nervous system. In this article, we shortly review the agonists of the alpha 7 nicotinic acetylcholine receptors that have been evaluated in vivo and we focused on the selective positive allosteric modulators of these receptors. These compounds represent a key element to enhance receptor activity only in the presence of the endogenous agonist.

关键词： α7 nicotinic receptors cholinergic anti-inflammatory pathway Alzheimer's disease huntington's disease Parkinson's disease neuroinflammation neurodegeneration positive allosteric modulators

Development of a nanostructured filter for pyrolysis wax purification:Effects of particulate filter aids

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Particuology 2021年第1期19卷 164-172页

作者： Juliano Missau daniel Assumpcao Bertuol Eduardo hiromitsu Tanabe Environmental Processes Laboratory(LAPAM) Chemical Engineering DepartmentFederal University of Santa Maria–UFSMAvenida Roraima 100097105-900Santa MariaRSBrazil

Wax obtained from the pyrolysis of polyethylene waste can contain inorganic contaminants and must be purified before *** evaluated different filter aids(perlite,sand,and rice husk ash)for the filtration of a crude wax and a pyrolysis wax through a filter medium that was coated with nylon 6 nanofibers to improve filtration *** first examined the performance of the filter aids in improving crude wax filtration,with the filtration time,temperature,and pressure held constant at 1 h,170℃,and 2.5 bar,*** wax was then produced by pyrolysis of high-density polyethylene(hDPE)waste in the temperature range 425-475℃.The best filter aid was perlite,which had a filtrate production rate of 5.47×10^(-5)m^(3)/*** highest oily wax yield(87.8%)was achieved at a pyrolysis temperature of 425℃.The assembly comprising the filter medium coated with nylon 6 nanofibers plus perlite as a filter aid was most suitable for removing impurities from the oily wax generated by the hDPE pyrolysis as it achieved a purification efficiency of 99.9%.

关键词： hDPE pyrolysis wax Plastic solid waste Nanofiber-coated filter Filter aids Filtration

Comparison of reduced point charge models of proteins: Molecular Dynamics simulations of Ubiquitin

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Science China Chemistry 2014年第10期57卷 1340-1354页

作者： LEhERTE Laurence VERCAUTEREN daniel P. Unité de Chimie Physique Théorique et Structurale Laboratoire de Physico-Chimie Informatique Namur MEdicine & Drug Innovation Center (NAMEDIC) Department of Chemistry University of Namur Rue de Bruxelles 61 B-5000 Namur Belgium

Reduced point charge models of amino acids are used to model Ubiquitin （PDB： 1UBQ）. They are designed （i） from local ex- tremum positions in charge density （CD） distribution functions built from the Poisson equation applied to smoothed molecular electrostatic potential functions, or （ii） from local maximum positions in promolecular electron density distribution （ED） func- tions. Charge values are fitted versus all-atom Amber99 molecular electrostatic potentials. The program GROMACS is used to generate molecular dynamics trajectories of the protein, under various implementation schemes, solvation, and temperature conditions. Point charges that are not located on atoms are considered as virtual sites with a null mass and radius. The results illustrate that secondary structure is best preserved with the CD-based model at low temperatures and in vacuum. This indi- cates that local potential energy wells are consistent with the all-atom model. however, at room temperature, the structure is best conserved when point charges are forced to be located on atoms, due to a better description of the Coulomb l-4 energy terms. The ED-based model, generated at a lower resolution, led to the largest discrepancies versus the all-atom case. The CD-based model allows the formation of protein-water h-bonds with geometrical properties similar to the all-atom ones. Con- trarily, intra-molecular h-bonds are not well described. Structural, thermodynamical, and dynamical properties of proteins modelled with reduced point charge models are also significantly affected by the choice of the solvent force field.

关键词： molecular electrostatic potential electron density smoothing of molecular fields critical points point charge model protein Ubiquitin

Probabilistic analysis of ultimate seismic bearing capacity of strip foundations

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 717-724页

作者： Adam hamrouni Badreddine Sbartai daniel Dias Laboratory InfraRes Mohammed Cherif Messaadia UniversitySouk-AhrasAlgeria Department of Civil Engineering Badji Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory LMGhU Skikda UniversitySkikdaAlgeria School of Automotive and Transportation Engineering Hefei University of TechnologyHefei230009China Grenoble Alpes University Laboratory 3SRGrenobleFrance

This paper presents a reliability analysis of the pseudo-static seismic bearing capacity of a strip foundation using the limit equilibrium theory. The first-order reliability method(FORM) is employed to calculate the reliability index. The response surface methodology(RSM) is used to assess the hasofer e Lind reliability index and then it is optimized using a genetic algorithm(GA). The random variables used are the soil shear strength parameters and the seismic coefficients(khand kv). Two assumptions(normal and non-normal distribution) are used for the random variables. The assumption of uncorrelated variables was found to be conservative in comparison to that of negatively correlated soil shear strength parameters. The assumption of non-normal distribution for the random variables can induce a negative effect on the reliability index of the practical range of the seismic bearing capacity.

关键词： Strip foundations Seismic bearing capacity First-order reliability method (FORM) Response surface methodology (RSM) Reliability Genetic algorithm (GA)

Potential of roots and shoots of Napier grass for arresting soil erosion and runoff of mollisols soils of himalayas

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International Soil and Water Conservation Research 2023年第3期11卷 538-548页

作者： Sushma Tamta Akhilesh Kumar daniel Prakash Kushwaha Krishi Vigyan Kendra Khodawandpur848202BegusaraiBiharIndia Department of Soiland Water Conservation Engineering G.B.Pant University of Agriculture and TechnologyPantnagar263145India

In this study, a soil filled hydraulic Tilting Flume (hTF) was used as a test plot under simulated rainfallconditions. This flume was flled with mollisols soils (sandy loam in texture) collected from tarai regionof himalayas. The effects of root and shoot characteristics of Napier grass in terms of leaf area index (LAI),shoot length (SL), number of leaves (NL), number of tillers (NT), shoot biomass (SB), root density (RD),root length (RL), root biomass (RB), and total biomass (TB) were investigated on runoff and sedimentoutflow at 90, 120 and 150 days after planting (DAP). Four simulated rainfall intensities namely 4.0, 6.5,8.3 and 9.4 cm/h over three land slopes of 1, 2 and 3% were selected. Runoff samples collected fromwhole plant plot and only root plot were analyzed for runoff and sediment outflow. Findings revealedthat Napier grasses were very effective to reduce runoff and sediment outflow and its efficacy increasedwith the extended growth stages. The reduction in runoff and sediment outflow at 90, 120 and 150 DAPwas obtained as 56% and 85%, 68% and 90%, and 74% and 96%, respectively, as compared to bare plotconditions. It was observed that the comparative contribution of shoots in runoff rate reduction washigher than the roots. On the contrary, the root part of the plant showed more contribution in sedimentrate reduction as compared to the shoot part. Step wise regression was attempted for the selection ofeffective input parameters to establish authentic runoff and sediment outflow models. Power form ofmultiple non-linear regression (MNLR) showed very satisfactory results for predicting runoff and sedimentoutflow with coefficient of determination (R^(2)) as 97.4% and 99.0%, respectively, root mean squareerror (RMSE) as 38.8 cc/m^(2)/min and 0.126 g/m^(2)/min, respectively, and coefficient of efficiency (CE) as93.9% and 96.7%, respectively, during testing period.

关键词： Rootand shoot characteristics Runoff and sedimentreduction Simulated rainfall conditions hydraulic tilting flume Step wise regression analysis

An all optical approach for comprehensive in-operando analysis of radiative and nonradiative recombination processes in GaAs double heterostructures

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Light(Science & Applications) 2022年第6期11卷 1206-1217页

作者： Fan Zhang Jose Fcastaneda Timothy hgfroerer daniel Friedman Yong-hang Zhang Mark Wwanlass Yong Zhang Department of Electrical and Computer Engineering The University of North Carolina at CharlotteCharlotteNC 28223USA Songshan Lake Materials Laboratory DongguanGuangdong 523808China Department of Physics Davidson CollegeDavidsonNC 28035USA National Renewable Energy Laboratory GoldenCO 80401USA School of Electrical Computer and Energy EngineeringArizona State UniversityTempeAZ 85287USA Wanlass Consulting NorwoodCO 81423USA

We demonstrate an all optical approach that can surprisingly offer the possibility of yielding much more information than one would expect,pertinent to the carrier recombination dynamics via both radiative and nonradiative processes when only one dominant deep defect level is present in a semiconductor *** applying a band-defect state coupling model that explicitly treats the inter-band radiative recombination and Shockley-Read-hall(SRh)recombination via the deep defect states on an equal footing for any defect center occupation fraction,and analyzing photoluminescence(PL)as a function of excitation density over a wide range of the excitation density(e.g.,5-6 orders in magnitude),in conjunction with Raman measurements of the LO-phonon plasmon(LOPP)coupled mode,nearly all of the key parameters relevant to the recombination processes can be *** include internal quantum efficiency(IQE),minority and majority carrier density,inter-band radiative recombination rate(Wr),minority carrier nonradiative recombination rate(Wnr),defect center occupation fraction(f)),defect center density(Nt),and minority and majority carrier capture cross-sections(σt andσtM).While some of this information is thought to be obtainable optically,such as IQE and the Wr/Wnr ratio,most of the other parameters are generally considered to be attainable only through electrical techniques,such as current-voltage(Ⅰ-Ⅴ)characteristics and deep level transient spectroscopy(DLTS).Following a procedure developed herein,this approach has been successfully applied to three GaAs double-heterostructures that exhibit two distinctly different nonradiative recombination *** method greatly enhances the usefulness of the simple PL technique to an unprecedented level,facilitating comprehensive material and device characterization without the need for any device processing.

关键词： radiative defect approach

Evidence for fine-scale habitat specialisation in an invasive weed

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Journal of Plant Ecology 2018年第2期11卷 189-199页

作者： daniel Z.Atwater Rebecca A.Fletcher Christopher C.Dickinson Andrew h.Paterson Jacob N.Barney Virginia Tech Department of Plant PathologyPhysiology and Weed Science435 Old Glade RoadBlacksburgVA 24061USA University of Georgia Plant Genome Mapping Laboratory111 Riverbend RoadAthensGA 30606USA

Aims As an exotic species colonises a new continent,it must overcome enormous environmental variation in its introduced *** adaptation of introduced species has frequently been observed at the continent scale,particularly in response to latitudinal climatic ***,significant environmental heterogeneity can also exist at the landscape scale.A small number of studies have provided evidence that introduced species may also be capable of phenotypic and genetic differentiation at much smaller spatial *** example,previously we found US agricultural and non-agricultural populations of Sorghum halepense(Johnsongrass)to be phenotypically and genetically *** this study,we inves-tigated whether this phenotypic differentiation of agricultural and non-agricultural populations of *** is the result of fine-scale local *** We surveyed a nationally collected *** germplasm panel and also collected neighbouring agricultural and non-agricultural sub-populations of *** at four sites throughout Western Virginia,USA,raising seedlings in common conditions mimicking both agricultural and non-agricultural *** Findings At the national scale,we found evidence of habitat differentiation but not ***,at the local scale,we found evi-dence of specialisation in two of the four local populations to non-agricultural habitat,but no evidence of specialisation to agricultural *** results show that local specialisation is a possible,but not guaranteed consequence of kilometre-scale habitat heterogen-eity in invasive *** finding contributes to a growing aware-ness of the importance of fine-scale local adaptation in the ecology and management of introduced and weedy species.

关键词： Johnsongrass local adaptation rapid evolution Sorghum halepense(L.)