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Do forest health threats affect upland oak regeneration and recruitment?Advance reproduction is a key co-morbidity

Forest Ecosystems 2023年第6期10卷 743-751页

作者： Lance A.Vickers Benjamin O.Knapp daniel c.Dey Lauren S.Pile Knapp School of Natural Resources University of Missouri203 Anheuser-Busch Natural Resources BuildingColumbiaMO65211USA USDA Forest Service Northern Research Station 202 Anheuser-Busch Natural Resources BuildingColumbiaMO65211USA

We analyzed national forest inventory data collected from circa 2000–2018 across 37 states in the eastern United States to better understand the influence of forest health related canopy disturbances on the regeneration and recruitment dynamics of upland oaks(Quercus).We found low levels of oak recruitment across all disturbance types examined but limited evidence of any direct effects from the type of disturbance on the population of regenerating *** general lack of differences in oak regeneration response between forest health disturbances and disturbances caused by harvested or non-disturbed plots does not indicate that the effects of forest health disturbances were benign,***,low level of oak recruitment across all disturbance types highlights the pervasiveness of the trend of shifting composition in once oak-dominated forests where oak is absent or sparse in the regeneration *** results show that oak recruitment was higher when oak was present as advance reproduction prior to disturbance from any cause ***,these results lead us to conclude that the widespread inadequacy of oak advance reproduction in mature oak-dominated forests is the prevailing threat to oak forest health and *** suggest the status of advance reproduction be treated as a co-morbidity when weighing the risk and potential outcomes from other threats to upland oak forests in the eastern United States.

关键词： Temperate deciduous forest Regeneration ecology Forest inventory and analysis Oak/hickory Forest pests Insect Disease Harvesting

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The importance of public engagement in clinical xenotransplantation

Health Care Science

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Health care Science 2024年第2期3卷 124-130页

作者： daniel J.Hurst David K.c.cooper Department of Family Medicine Rowan-Virtua School of Osteopathic MedicineStratfordNew JerseyUSA center for Transplantation Sciences Massachusetts General Hospital/Harvard Medical SchoolBostonMassachusettsUSA

Over the past several decades,significant scientific progress in xenotransplantation has brought the field to the threshold of clinical *** the past 3 years in the United States,experimental pig kidney and heart xenotransplantation have been performed on human subjects recently declared dead by neurological criteria(decedents).In addition,two pig heart transplants have been carried out in living patients under the United States Food and Drug Administration's expanded access ***,though there has been a flurry of activity there remain unanswered questions regarding how the public views xenotransplantation,what concerns may exist,and how to address these concerns in a meaningful *** paper aims to underscore the importance of public engagement in xenotransplantation,emphasizing the ongoing need for studies to assess public *** current evidence on public engagement studies is reviewed and gaps in our understanding are *** propose practical steps to advance this *** studies to determine the extent of racial/ethnic differences in attitudes to xenotransplantation should be *** and descriptive analysis of certain religious viewpoints—especially minority faiths—would be *** public engagement is an important aspect of public acceptance of novel research that is accompanied by risk,we suggest that xenotransplantation biotechnology companies might consider leading the way in funding this research.

关键词： clinical trials ethics public engagement viewpoints xenotransplantation

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Intermediate conductance, ca^2＋-activated K^＋ channels： a novel target for chronic renal diseases

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Frontiers in Biology 2015年第1期10卷 52-60页

作者： claudia A. BERTUccIO daniel c. DEVOR Department of cell Biology School of Medicine University of Pittsburgh Pittsburgh PA 15261 USA

Renal failure is a medical condition in which the kidneys are not working properly. There are two types of kidney failure： 1） acute kidney failure, which is sudden and often reversible with adequate treatment; and 2） chronic renal failure, which develops slowly and often is not reversible. The last stage of chronic renal failure is fatal without dialysis or kidney transplant. The treatment for chronic renal failure is focusing on slowing the progression of kidney damage. Several reports have described a promising approach to slow the loss of renal function through inhibition of the basolateral membrane, ca^2＋-activated K^＋（Kca3.1） channel with a selective and nontoxic blocker TRAM-34. This review summarizes pathophysiological studies that describe the role of Kca3.1 in kidney diseases.

关键词： ca^2+-activated K^+ channels Kca3.1 renal fibrosis polycystic kidney disease diabetes nephropathy transplant,cell proliferation c1 secretion renal failure

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Modelling policy combinations of vaccination and transmission suppression of SARS-coV-2 in Rio de Janeiro,Brazil

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Infectious Disease Modelling 2022年第1期7卷 231-242页

作者： Naiara c.M.Valiati daniel A.M.Villela Universidade Federal Rural do Rio de Janeiro SeropedicaRJBrazil Programa de computaçao científica Fundaçao Oswaldo CruzRio de JaneiroRJBrazil

cOVID-19 vaccination in Brazil required a phased program,with priorities for age groups,health workers,and vulnerable *** distancing and isolation interventions have been essential to mitigate the advance of the pandemic in several *** developed a mathematical model capable of capturing the dynamics of the SARS-coV-2 dissemination aligned with social distancing,isolation measures,and *** data from the city of Rio de Janeiro provided a case study to analyze possible scenarios,including non-pharmaceutical interventions and vaccination in the epidemic *** results demonstrate that the combination of vaccination and policies of transmission suppression potentially lowered the number of hospitalized cases by 380þand 66þthousand cases,respectively,compared to an absence of such *** top of transmission suppressiononly policies,vaccination impacted more than 230þthousand averted hospitalized cases and 43þthousand averted ***,health surveillance activities should be maintained along with vaccination planning in scheduled groups until a large vaccinated coverage is ***,this analytical framework enables evaluation of such scenarios.

关键词： SARS-coV-2 Vaccination cOVID-19

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A pentaploid-based linkage map of the ancestral octoploid strawberry Fragaria virginiana reveals instances of sporadic hyper-recombination

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Horticulture Research 2020年第1期7卷 1796-1810页

作者： Thomas M.Davis Yilong Yang Lise L.Mahoney daniel c.Frailey Department of Agriculture Nutritionand Food SystemsUniversity of New HampshireDurhamNH 03824USA

The first high-resolution genetic linkage map of the ancestral octoploid(2n=8x=56)strawberry species,Fragaria virginiana,was constructed using segregation data obtained from a pentaploid progeny *** novel mapping population of size 178 was generated by crossing highly heterozygous *** hybrid“LB48”as a paternal parent with diploid(2n=2x=14)Fragaria vesca“Hawaii 4”.The LB48 linkage map comprises 6055 markers genotyped on the Axiom®IStraw90 strawberry SNP *** map consists of 28 linkage groups(LGs)organized into seven homoeology groups of four LGs each,and excludes a small 29th LG of undefined *** member of each homoeology group was assignable to an“A”subgenome associated with ancestral diploid Fragaria vesca,while no other subgenomes were *** an intriguing discrepancy within homoeology group VI,synteny comparisons with the previously published Fragaria×ananassa DA×MO linkage map revealed substantial *** initial map construction,examination of crossover distributions revealed that six of the total 5162(=29 chromosomes/individual×178 individuals)chromosomes making up the data set exhibited abnormally high crossover counts,ranging from 15 to 48 crossovers per chromosome,as compared with the overall mean of 0.66 crossovers per *** of these six hyper-recombinant(HypR)chromosomes occurred in a different LG and in a different *** calculated upon exclusion of the six HypR chromosomes,the canonical(i.e.,broadly representative)LB48 map had 1851 loci distributed over a total map length of 1873 cM,while their inclusion increased the number of loci by 130,and the overall map length by 91 *** of these hyper-recombinant chromosomes points to the existence of a sporadically acting mechanism that,if identified and manipulable,could be usefully harnessed for multiple purposes by geneticists and breeders.

关键词： Fragaria straw linkage

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Estimation of solids circulation rate and char transfer rate from gasifier to combustor in a dual fluidized-bed pilot plant for biomass steam gasification

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Particuology 2019年第5期17卷 22-29页

作者： M. Hafizur Rahman Lius daniel Ujash Shah Xiaotao Bi John R. Grace c.Jim Lim Fluidization Research centre Department of Chemical & Biological Engineering University of British Columbia 2360 East Mall Vancouver British Columbia V6T1Z3 Canada

Operation of a dual fluidized bed, consisting of a riser as combustor and bubbling bed as gasifier, for synthesis gas production from a solid fuel requires determination of the solids circulation rate and char transfer rate. The performance relies on supplying sufficient heat from the combustor to the gasifier by circulation of solids between these two reactors. The flow rate of char is required to track the heat generated in the combustor, which supports endothermic reactions in the gasifier. Direct measurement of these two critical parameters is difficult, with the number of reported techniques capable of working at high temperatures extremely small. An indirect method was developed, using mass and energy balances over the entire system and individual reactors, to estimate the solids circulation rate and char transfer rate. There was general agreement between heat losses estimated from energy-balance calculations and from direct measurement of the outer reactor surface temperature. Under typical gasification conditions, the solids circulation fluxes were estimated to be 45.2 and 55.6 kg/(m^2 s) in two independent tests, which were in good agreement with values obtained using a thermal tracer;char transfer rates were calculated to be 1.2 and 0.6 kg/h, which were in reasonable agreement with average biomass feed rates. This method can be applied to dual gasification systems at any temperature or flow rate.

关键词： Solids circulation rate char transfer rate Pilot-plant gasifier Dual fluidized bed Mass and energy balance

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Detection of mechanical stress in the steel structure of a bridge crane

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Theoretical & Applied Mechanics Letters 2021年第6期11卷 320-329页

作者： Leopold Hrabovsky daniel cepica Karel Frydrysek VSB-Technical university of Ostrava Faculty of mechanical EngineeringInstitute of Transport17.listopadu 2172/1570800Ostrava-PorubaCzech Republic VSB-Technical university of Ostrava Faculty of Mechanical EngineeringDepartment of Applied MechanicsOstrava-PorubaCzech Republic

A significant negative aspect in the operation of bridge-type cranes are the technical problems associated with wear of the wheels and the crane track,which causes crane *** main causes of crane skewing include unevenness of the crane track,unequal loading of the traction drives depending on the position of the crane trolley,slips and different sizes of travel wheels and combinations of these ***,this paper presents a design solution that can be used to detect the magnitude of mechanical stress and deformation of the steel structure of the crane,caused by the effects of *** mechanical stress generated by the transverse forces of the deformed geometric shape of the crane bridge structure is recorded by mechanical stress detectors installed in the inner corners of the crane *** resulting electrical signal from element mechanical voltage detectors,loaded by axial forces,can be used for feedback control of separate crane travel drives controlled by frequency ***,this paper presents the calculation of the lateral transverse forces according to cSN 270103 and the determination of the values of mechanical stresses of the deformed steel structure of the crane bridge of a two-girder bridge crane using the finite element method in the program *** ***,this paper presents the structural and strength design of mechanical stress detectors and the conclusions of laboratory tests of axial force loading of mechanical stress detectors on the test *** the same time,it presents records of the measured axial forces acting in the mechanical stress detectors,arising from the deformation and warping of the crane bridge by the known magnitude of the axial force acting on the crossbeam and from the deformation of the crane bridge caused by the crane operating modes.

关键词： crane skewing Mechanical stress detector Mechanical stress FEM Overhead crane

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Interactive influence of rainfall manipulation and livestock grazing on species diversity of the herbaceous layer community in a humid savannah in Kenya

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Plant Diversity 2019年第3期41卷 198-205页

作者： Joseph O.Ondier daniel O.Okach John c.Onyango Dennis O.Otieno Department of Botany Maseno University Private Bag Maseno Kenya Department of Biological Sciences Jaramogi Oginga Odinga University of Science and Technology P.O Box 210-40601 Bondo Kenya Department of Plant Ecology University of Bayreuth D-95440 Bayreuth Germany

changes in rainfall regime and grazing pressure affect vegetation composition and diversity with ecological implications for savannahs. The savannah in East Africa has experienced increased livestock grazing and rainfall variability but the impacts associated with those changes on the herbaceous layer have rarely been documented. We investigated the effect of livestock grazing, rainfall manipulation and their interaction on the composition and diversity of the herbaceous community in the savannah for two years in Lambwe, Kenya. Rainfall manipulation plots were set up for vegetation sampling;these plots received either 50% more or 50% less rainfall than control plots. Simpson’s diversity and Bergere Parker indices were used to determine diversity changes and dominance respectively. The frequency of species was used to compute their abundance and their life forms as determined from the literature. Grazing significantly increased species diversity through suppression of dominant species. Rainfall manipulation had no significant impact on plant diversity in fenced plots, but rainfall reduction significantly reduced diversity in grazed plots. In contrast, rainfall manipulation had no impact on dominance in either fenced or grazed plots. The interaction of grazing and rainfall manipulation is complex and will require additional survey campaigns to create a complete picture of the implications for savannah structure and composition.

关键词： Plant diversity Grazing Rainfall Moist savannah

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Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI daniel PUYOL Mirna c. MARTiNEZ Emiliano E. DLAZ Jose L. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of chemical Engineering University Autonoma of Madrid Madrid 28049 Spain MYGEN Laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the cOD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

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Two-tiered reconstruction of Late Pleistocene to Holocene changes in the freezing level height in the largest glacierized areas of the colombian Andes

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Journal of Mountain Science 2022年第3期19卷 615-636页

作者： daniel RUIZ-cARRAScAL daniel GONZALEZ-DUQUE Isabel RESTREPO-cORREA Department of Ecology Evolution and Environmental BiologyColumbia University in the City of New YorkNew YorkNY 10027USA Department of civil and Environmental Engineering Vanderbilt University40024th Avenue South269 Jacobs HallNashville TN 3720USA Department of Earth Sciences Universidad EAFITCarrera 49 No.7Sur-50MedellínColombia

One way of deducing vertical shifts in the altitudinal distribution of colombian high-altitude páramo environments is by inferring fluctuations in the height of the local freezing *** our research,we are implementing two complementary approaches to reconstruct Late Pleistocene to Holocene changes in the freezing level height(FLH)in two of the most extensively glacier-covered areas of the northern *** combined remote sensing and field-based geomorphological mapping with time-series reconstruction of changes in the altitude of the 0°c *** in the FLH were based on alreadypublished~30 kyr paleo-reconstructions of sea surface temperatures(SSTs)of the eastern tropical Pacific and the western tropical Atlantic,as well as on reconstructed long-term sea level changes and empirical orthogonal functions of present-day(historical)Indo-Pacific and tropical Atlantic SST *** also analyzed the probability distribution of air-sea temperature differences and the spatial distribution of grid points with SSTs above the minimum threshold necessary to initiate deep *** considered available historical nearsurface and free air temperature data of ERA-Interim reanalysis products,General circulation Model(GcM)simulations,weather stations,and(deployed by our group)digital sensors,to assess the normal Environmental Lapse Rates(ELRs)at the regional to local *** combined maps of glacial landforms and our reconstructed FLHs provided us with a wellfounded inference of potential past glacier advances,narrowing down the coarse resolution of ice margins suggested by previous research *** extent of the areas with temperatures below the freezing point suggested here for the summits of our main study site exceeds in magnitude the corresponding glacier icecaps and front advances proposed by previous ***,our average lowest altitudes of the FLH for our comparative site are consistently above the main glacier-front advances previously su

关键词： Glacial events colombian Andes climate reconstruction Geomorphology Mountain glaciers Freezing level height

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