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Space Deformations,Surface Deformations and the Opportunities In-Between

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Journal of Computer Science & Technology 2009年第1期24卷 2-5页

作者： daniel Cohen-Or School of Computer Science Tel-Aviv UniversityIsrael

In recent years we have witnessed a large interest in surface deformation techniques. This has been a reaction that can be attributed to the ability to develop techniques which are detail-preserving. Space deformation techniques, on the other hand, received less attention, but nevertheless they have many advantages over surface-based techniques. This paper explores the potential of these two approaches to deformation and discusses the opportunities that the fusion of the two may lead to.

关键词： space deformation mesh editing digital surfaces

Mating system and genetic diversity of a rare desert legume Ammopiptanthus nanus (Leguminosae)

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Journal of Systematics and Evolution 2009年第1期47卷 57-66页

作者： daniel J CRAWFORD Department of Ecology and Evolutionary Biology and the Natural History Museum and Biodiversity Research CenterThe University of Kansas

Ammopiptanthus nanus is an endangered evergreen shrub endemic to the deserts of central Asia and plays an important role in delaying further desertification. We examined allozyme variation and AFLP diversity in A. nanus populations and investigated the mating system of this species using progeny arrays assayed for poly-morphic allozyme loci. Mating system analysis in the Keyi’eryongke’er population showed low levels of out-crossing, and strong inbreeding depression. Low levels of genetic variation were detected at both population (allozyme, Pp=14.0%, A=1.14, he=0.031; AFLP, Pp=14.5%, Shannon’s information index I=0.063) and species (allozyme, Pp=21.1%, A=1.21, he=0.040; AFLP, Pp=20.9%, I=0.083) levels; while moderate genetic differentiation existed among populations, as indicated by allozymes (GST=0.081) and AFLP (GST=0.151-0.193). Founder effect, bottlenecks in evolutionary history, the mixed mating system and co-ancestry may have influenced the level of genetic diversity in A. nanus. Markers of both types provide new insights for conservation management, indicating that the Biao’ertuokuoyi and Keyi’eryongke’er populations should be given priority for in situ conservation and regarded as seed sources for ex situ conservation.

关键词： AFLP allozyme Ammopiptanthus conservation endangered plant genetic structure outcrossing rate

Enriching plant diversity in grasslands by large-scale experimental sward disturbance and seed addition along gradients of land-use intensity

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Journal of Plant Ecology 2017年第4期10卷 581-591页

作者： Valentin h.Klaus Deborah Schäfer Till Kleinebecker Markus Fischer daniel Prati Norbert hölzel Institute of Landscape Ecology Münster UniversityHeisenbergstr.248149 MünsterGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland

Aims The relationship between biodiversity and ecosystem functioning is among the most active areas of ecological ***,enhancing the diversity of degraded ecosystems is a major goal in applied restoration *** grasslands,many species may be locally absent due to dispersal or microsite limitation and may therefore profit from mechanical disturbance of the resident *** established a seed addition and disturbance experiment across several grassland sites of different land use to test whether plant diversity can be increased in these ***,the experiment will allow us testing the consequences of increased plant diversity for ecosystem processes and for the diversity of other taxa in real-world ***,we present details of the experimen-tal design and report results from the first vegetation survey 1 year after disturbance and seed ***,we tested whether the effects of seed addition and disturbance varied among grassland depending on their land use or pre-disturbance plant *** A full-factorial experiment was installed in 73 grasslands in three regions across *** were under regular agricul-tural use,but varied in the type and the intensity of management,thereby representing the range of management typical for large parts of Central *** disturbance treatment consisted of disturbing the top 10 cm of the sward using a rotavator or rotary *** addition consisted of sowing a high-diversity seed mixture of regional plant *** species were all regionally present,but often locally absent,depending on the resident vegetation composi-tion and richness of each *** Findings Seven months after sward disturbance,respective plots had significantly increased in bare soil,seedling species richness and number of *** addition had increased plant species richness,but only in combination with sward *** increase in species richness

关键词： grassland restoration germination microsite limitation seed limitation fertilization

Recovery of valuable metals from waste cables by employing mechanical processing followed by spouted bed elutriation

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Particuology 2019年第4期17卷 74-80页

作者： Eduardo h. Tanabe Roger M. Silva Daliomar L. Oliveira Junior daniel A. Bertuol Environmental Processes Laboratory (LAPAM) Chemical Engineering Department Federal University of Santa Maria - UFSM Santa Maria RS Brazil

Cables and wires, which are essential parts of equipment for the transmission of both information and electricity, contain valuable materials including copper (Cu) and aluminum (Al). This experimental work evaluates the use of mechanical processing (grinding and sieving), followed by spouted bed elutriation, for separation of the valuable materials (steel-coated copper, copper, and aluminum) present in waste coaxial and internet cables. A recovery efficiency of approximately 90% was achieved for the steel-coated copper in coaxial cables. For in ternet cables, the copper recovery efficiency was approximately 87%. These findings dem on strate that it is possible to separate, recover, and recycle the valuable materials (metals) present in waste cables using simple, low-cost, and efficient mechanical processing followed by spouted bed elutriation.

关键词： Waste cable Elutriation Copper Recycling Mechanical process

Crop adaptation to climate change:An evolutionary perspective

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Molecular Plant 2023年第10期16卷 1518-1546页

作者： Lexuan Gao Michael B.Kantar Dylan Moxley daniel Ortiz-Barrientos Loren h.Rieseberg CAS Center for Excellence in Molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China Department of Tropical Plant&Soil Sciences University of Hawaii at ManoaHonoluluHIUSA Department of Botany and Biodiversity Research Centre University of British ColumbiaVancouverBCCanada School of Biological Sciences and Australian Research Council Centre of Excellence for Plant Success in Nature and Agriculture The University of QueenslandBrisbaneQLDAustralia

The disciplines of evolutionary biology and plant and animal breeding have been intertwined throughout their development,with responses to artificial selection yielding insights into the action of natural selection and evolutionary biology providing statistical and conceptual guidance for modern *** we offer an evolutionary perspective on a grand challenge of the 21st century:feeding humanity in the face of climate *** first highlight promising strategies currently under way to adapt crops to current and future climate *** include methods to match crop varieties with current and predicted environments and to optimize breeding goals,management practices,and crop microbiomes to enhance yield and sustainable *** also describe the promise of crop wild relatives and recent technological innovations such as speed breeding,genomic selection,and genome editing for improving environmental resilience of existing crop varieties or for developing new ***,we discuss how methods and theory from evolutionary biology can enhance these existing strategies and suggest novel *** focus initially on methods for reconstructing the evolutionary history of crops and their pests and symbionts,because such historical information provides an overall framework for crop-improvement *** then describe how evolutionary approaches can be used to detect and mitigate the accumulation of deleterious mutations in crop genomes,identify alleles and mutations that underlie adaptation(and maladaptation)to agricultural environments,mitigate evolutionary trade-offs,and improve critical *** feedback between the evolution and crop biology communities will ensure optimal design of strategies for adapting crops to climate change.

关键词： abiotic stress resistance climate change crop adaptation Darwinian agriculture evolutionary biology plant breeding

Extent of morbidity associated with schistosomiasis infection in Malawi: a review paper

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Infectious Diseases of Poverty 2015年第1期4卷 185-192页

作者： Austin h N Mtethiwa Gamba Nkwengulila Jared Bakuza daniel Sikawa Abigail Kazembe Lilongwe University of Agriculture and Natural Resources(LUANAR) Bunda CampusPO Box 219LilongweMalawi Zoology Department University of Dar es SalaamCollege of Natural and Applied SciencePO Box 35064Dar es SalaamTanzania Biological Sciences Unit Dar es Salaam University College of Education(DUCE)PO Box 2329Dar es SalaamTanzania University of Malawi Kamuzu College of NursingPrivate Bag 1LilongweMalawi

Data on the extent of the burden due to schistosomiasis is sparse in most Sub-Saharan African ***,this data is crucial for triggering medical attention.A review of extent of morbidity and determinants associated with schistosomiasis in Malawi was therefore conducted to quantify the infection in order to concretise the need for medical intervention.A systematic and traditional search strategy was used to find literature for the review,whilst exclusion and inclusion criteria were used to identify appropriate *** regression curves of epidemiological model Y=(a+bxc)/(1+bxc)and the recommendation that schistosomiasis prevalence can be used to estimate morbidity were employed to quantify morbidity at various infection *** was quantified as a direct proportion of the population and the respective national schistosomiasis *** showed that both *** and *** are present in Malawi with the latter highly prevalent(50%).Furthermore,out of the estimated population of 16,829 million,approximately 8.4 million have schistosomiasis,with about 4.4 million of these aged 18 years and *** most frequent manifestation is Katayama syndrome,while ascites is the lowest,impacting about 3.0 million and 960 individuals,*** studies on association of schistosomiasis infection to risk factors such as occupation,age and gender found odds ratio(OR)ranging from 1.29 to *** due to schistosomiasis is high in *** is therefore recommended that a more detailed study on the determinants of high schistosomiasis and re-evaluation of the current control measures be conducted if the current morbidity statistics are to be remarkably reduced.

关键词： Schistosomiasis Morbidity Risk factors Quantification Burden Extent

Fluidization behavior and reducibility of iron ore fines during hydrogen-induced fluidized bed reduction

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Particuology 2020年第5期18卷 36-46页

作者： daniel Spreitzer Johannes Schenk Chair of Ferrous Metallurgy Montanuniversitaet LeobenFranz-Josef-Straβe 188700 LeobenAustria

A laboratory fluidized bed reactor was used to investigate the fluidization behavior and reducibility of various iron ore *** was chosen as a reducing agent across a temperature range of 873-1073 *** magnetite ore used exhibited strong sticking behavior after the initiation of metallic iron *** other tested ores fluidized sufficiently well when subjected to the same high reduction *** kinetic analysis was conducted using a previously developed model to include three rate-limiting step *** trend of apparent activation energy was correlated with the degree of ***,the influence of varying the specific gas rate was *** results show the variation in reducibility as a result of different interactions,which influence the rate-limiting mechanisms of nucleation and the undertaken chemical reactions,which vary as a function of temperature and degree of *** apparent activation energies,determined from the reduction of wtistite to metallic iron,were in the range of 15-60 kJ/mol,depending on the iron ore used and the degree of *** change in apparent activation energy deriving from the increased specific gas rate can be explained by an increasing nucleation effect,especially at lower reduction temperatures.

关键词： Fluidized bed Iron ore reduction hydrogen Fluidization behavior Kinetic analysis

Interplay of transport processes and interfacial chemistry affecting chromium reduction and reoxidation with iron and manganese

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 55-63页

作者： Chao Pan daniel Giammar Department of Energy Environmentaland Chemical EngineeringWashington University in St.LouisSt.LouisMO 63130USA Present affiliation:Glenn *** Institute Physical&Life SciencesLawrence Livermore National LaboratoryLivermoreCA 94550USA

hexavalent chromium(Cr(Ⅵ))is a water-soluble pollutant in soil and groundwater,the mobility,bioavailability,and toxicity of which can be controlled by transforming to less mobile and more environmentally benign Cr(Ⅲ)by ways of *** review focused on recent advances in identifying the reaction pathways,kinetics,and products of iron-based techniques for Cr(Ⅵ)*** also examines new information regarding remobilization of Cr(Ⅲ)in the existence of complexing ligands and manganese(Mn)of different oxidation states.A range of iron-based techniques can remove Cr(Ⅵ)from water by adsorption or reduction-coprecipitation ***,the success of a chromium treatment or remediation strategy requires the stability of the Cr(Ⅲ)-containing solids with respect to solubilization or reoxidation in the settings they are *** is ubiquitous in aquatic and terrestrial environments,and the redox cycling of manganese may greatly influence the fate,transport,and distribution of *** of redox reactions of chromium,iron,and manganese involves reaction pathways not only in the aqueous phase but also at solid-aqueous *** provide a quantitative understanding of these processes,it is essential to develop mechanistically based kinetic and transport *** research should be made on iron-based treatment of Cr(Ⅵ)-contaminated water and soils and the stability of the subsequently produced Cr(Ⅲ)-containing solids at environmentally relevant conditions,which will support improved predictions of chromium's environmental fate and transport and aid in decision-making for remediation and treatment of Cr contamination.

关键词： Chromium(Ⅵ)contamination Redox reaction Iron oxide Manganese oxide Modeling

Neuronal circuitry reconstruction after stem cell therapy in damaged brain

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Neural Regeneration Research 2022年第9期17卷 1959-1960页

作者： daniel Tornero Department of Biomedical Sciences Institute of Neuroscience and Production and Validation Center of Advanced Therapies(Creatio)University of Barcelona August Pi I Sunyer Biomedical Research Institute(IDIBAPS) Network Center for Biomedical Research in Neurodegenerative Diseases(CIBERNED) BarcelonaSpain

Transplantation of neuronal precursors derived from human pluripotent stem cells is a promising therapy for the treatment of neurological disorders associated with neuronal loss,such us neurodegenerative diseases,brain trauma and *** functional integration of grafted neurons differentiated from stem cells into the host injured neuronal circuitry has been a major challenge in cell therapy strategies for brain repair(Palma-Tortosa et al.,2021).Even though other cell types or mechanisms may provide modest clinical improvements,neuronal replacement and reconstruction of the damaged area are crucial for an optimal and long-term recovery.

关键词： diseases damaged