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Prioritizing woody species for the rehabilitation of arid lands in western Iran based on soil properties and carbon sequestration

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Journal of Arid Land 2020年第4期12卷 640-652页

作者： Masoud BAZGIR Reza OMIDIPOUR Mehdi HEYDARI Nasim ZAINALI Masoud HAMIDI daniel c DEY Department of Water and Soil Engineering Faculty of AgricultureIlam UniversityIlam ***Iran Department of Range and Watershed Management Faculty of Natural Resource and Earth ScienceShahrekord UniversityShahrekord ***Iran Department of Forestry Faculty of AgricultureIlam UniversityIlam ***Iran us Forest Service Northern Research StationColumbiaOM 65211USA

Plants are an important component in many natural ecosystems. They influence soil properties, especially in arid ecosystems. The selection of plant species based on their adaptations to site conditions is essential for rehabilitation of degraded sites and other construction sites such as check-dams. Other factors to be considered in species selection include their effects on soil properties and their abilities to meet other management objectives. The purpose of this study was to assess the effects of native(Populus euphratica Oliv. and Tamarix ramosissima Ledeb.) and introduced(Eucalyptus camaldulensis Dehnh. and Prosopis juliflora(Swartz) Dc.) woody species on soil properties and carbon sequestration(cS) in an arid region of Iran. Soil sampling was collected at three soil depths(0–10, 10–20 and 20–30 cm) at the sites located under each woody species canopy and in an open area in 2017. Soil physical-chemical property was analyzed in the laboratory. The presence of a woody species changed soil characteristics and soil cS, compared with the open area. For example, the presence of a woody species caused a decrease in soil bulk density, of which the lowest value was observed under E. camaldulensis(1.38 g/cm^3) compared with the open area(1.59 g/cm^3). Also, all woody species significantly increased the contents of soil organic matter and total nitrogen, and introduced species had more significant effect than native species. The results showed that cS significantly increased under the canopy of all woody species in a decreasing order of P. euphratica(9.08 t/hm^2)>E. camaldulensis(8.37 t/hm^2)>P. juliflora(5.20 t/hm^2)>T. ramosissima(2.93 t/hm^2)>open area(1.33 t/hm^2), thus demonstrating the positive effect of a woody species on cS. Although the plantation of non-native species had some positive effects on soil properties, we recommend increasing species diversity in plantations of native and introduced woody species to provide more diversity for the increased ecosystem

关键词： arid ecosystem carbon sequestration degraded soil restoration reforestation soil management

compressively sampling the optical transmission matrix of a multimode fibre

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Light(Science & Applications) 2021年第5期10卷 916-930页

作者： Shuhui Li charles Saunders daniel J.lum John Murray-Bruce Vivek K Goyal TomášČižmár David B.Phillips School of Physics and Astronomy University of ExeterExeterEX44QLUK Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan430074HubeiChina Department of Electrical and computer Engineering Boston UniversityBostonMA02215USA Department of Physics and Astronomy University of Rochester500 Wilson BlvdRochesterNY14618USA Department of computer Science and Engineering University of South FloridaTampaFL33620USA Leibniz Institute of Photonic Technology Albert-Einstein-Straße 907745JenaGermany Institute of Scientific Instruments of cAS Královopolská14761264BrnoCzech Republic

The measurement of the optical transmission matrix(TM)of an opaque material is an advanced form of space-variant aberration *** imaging,TM-based methods are emerging in a range of fields,including optical communications,micro-manipulation,and *** many cases,the TM is very sensitive to perturbations in the configuration of the scattering medium it ***,applications often require an up-to-the-minute characterisation of the fragile TM,typically entailing hundreds to thousands of probe ***,we explore how these measurement requirements can be relaxed using the framework of compressive sensing,in which the incorporation of prior information enables accurate estimation from fewer measurements than the dimensionality of the TM we aim to *** of such priors include knowledge of a memory effect linking the input and output fields,an approximate model of the optical system,or a recent but degraded TM *** demonstrate this concept by reconstructing the full-size TM of a multimode fibre supporting 754 modes at compression ratios down to∼5%with good *** show that in this case,imaging is still possible using TMs reconstructed at compression ratios down to∼1%(eight probe measurements).This compressive TM sampling strategy is quite general and may be applied to a variety of other scattering samples,including diffusers,thin layers of tissue,fibre optics of any refractive profile,and reflections from opaque *** approaches offer a route towards the measurement of high-dimensional TMs either quickly or with access to limited numbers of measurements.

关键词： scattering fibre matrix

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

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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

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

concentration–discharge patterns of weathering products from global rivers

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Acta Geochimica 2017年第3期36卷 405-409页

作者： daniel E.Ibarra Seulgi Moon Jeremy K.caves c.Page chamberlain Kate Maher Earth System Science Stanford University StanfordCA 94305-4216 USA Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Earth Science ETH Ziirich 8092 Zurich Switzerland Geological Sciences Stanford University StanfordCA 94305-2115 USA

Quantifying the functional relationships relating river discharge and weathering products places key constraints on the negative feedback between the silicate weathering and climate. In this study we analyze the concentration–discharge relationships of weathering products from global rivers using previously compiled time-series datasets for concentrations and discharge from global rivers. To analyze the nature of the covariation between specific discharge and concentrations, we use both a power law equation and a recently developed solute production equation. The solute production equation allows us to quantify weathering efficiency, or the resistance to dilution at high runoff, via the Damkohler coefficient. These results are also compared to those derived using average concentration–discharge *** the power law exponent and the Damkohler coefficient increase and asymptote as catchments exhibit increasingly chemostatic behavior, resulting in an inverse relationship between the two parameters. We also show that using thedistribution of average concentration–discharge pairs from global rivers, rather than fitting concentration–discharge relationships for each individual river, underestimates global median weathering efficiency by up to a factor of ～10. This study demonstrates the utility of long time-series sampling of global rivers to elucidate controlling processes needed to quantify patterns in global silicate weathering rates.

关键词： concentration–discharge Rivers Silicate weathering Solutes

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.)

The association between sexual function and prostate cancer risk in us veterans

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Asian Journal of Andrology 2017年第2期19卷 191-195页

作者： daniel F Zapata Lauren E Howard Jennifer Frank Ross M Simon cathrine Hoyo Delores J Grant Stephen J Freedland Adriana c Vidal Duke University Medical center Division of Urology Department of Surgery Durham NC 27710 USA Durham Veterans Affairs Medical center Urology Division Durham NC 27710 USA North carolina State University Department of Biology Raleigh NC 27695 USA North carolina central University Department of Biology Durham NC 27707 USA Department of Surgery Division of Urology Samuel Oschin Comprehensive Cancer institute Cedars-Sinai Medical Center Los Angeles California 90048 USA

Sexual dysfunction and prostate cancer are common among older men. Few studies explored the association between these two illnesses. We examined whether sexual function is associated with prostate cancer risk among older men. Among 448 men undergoing prostate biopsy at the Durham Veterans Affairs Hospital, sexual function was ascertained from the Expanded Prostate cancer Index composite sexual assessment. We tested the link between sexual function and prostate cancer risk adjusting for multiple demographic and clinical characteristics using logistic regression. Multinomial logistic regression was used to test the associations with risk of low-grade （Gleason 〈6） and high-grade （Gleason 〉7 or 〉4 ＋ 3） disease versus no cancer. Of 448 men, 209 （47%） had a positive biopsy; these men were less likely to be white （43% vs 55%, P=0.013）, had higher prostate-specific antigen （PSA）（6.0 vs 5.4 ng ml-1, P 〈 0.001）, but with lower mean sexual function score （47 vs 54, P = 0.007）. There was no difference in age, BMI, pack years smoked, history of heart disease and/or diabetes. After adjusting for baseline differences, sexual function was linked with a decreased risk of overall prostate cancer risk （OR. 0.91 per lO-point change in sexual function, P= 0.004） and high-grade disease whether defined as Gleason ≥7 （OR： 0.86, P= 0.001） or 〉4 ＋ 3 （OR： 0.85, P= 0.009）. Sexual function was unrelated to low-grade prostate cancer （OR： 0.94, P = 0.13）. Thus, among men undergoing prostate biopsy, higher sexual function was associated with a decreased risk of overall and high-grade prostate cancer. confirmatory studies are needed.

关键词： erectile dysfunction prostate prostate cancer risk sexual function

Positive Solutions for Singular Quasilinear Schrodinger Equations with One Parameter, II

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Journal of Partial Differential Equations 2010年第3期23卷 222-234页

作者： MOAMENI Abbas OFFIN daniel c. Division of Sciences and Engineering American University of Kuwait Safat 13034 Kuwait Department of Mathematics and Statistics Queen's University Kingston Canada

We establish the existence of positive bound state solutions for the singular quasilinear Schrodinger equation iψ/t=-div（ρ（｜ψ｜^2） ψ）＋ω（｜ψ｜62）ψ-λρ（｜ψ｜^2）ψ,x∈Ω,t〉0,where ω（τ^2）τ→∞ as τ→ 0 and, λ 〉 0is a parameter and Ω is a ball in ^RN. This problem is studied in connection with the following quasilinear eigenvalue problem with Dirichlet boundary condition -div（ρ（｜ ψ｜^2） ψ）=λ1ρ（｜ψ｜^2）ψ=λ1ρ（｜ψ｜^2）ψ,x∈Ω.Indeed, we establish the existence of solutions for the above Schrodinger equation when A belongs to a certain neighborhood of the first eigenvahie λ1 of this eigenvalue problem. The main feature of this paper is that the nonlinearity ω｜ψ｜^2 is unbounded around the origin and also the presence of the second order nonlinear term. Our analysis shows the importance of the role played by the parameter A combined with the nonlinear nonhomogeneous term div （ρ（｜ ψ｜^2） ψ） which leads us to treat this prob- lem in an appropriate Orlicz space. The proofs are based on various techniques related to variational methods and implicit function theorem.

关键词： Schrodinger equations solitary waves variational methods.

Silk fibroin as an additive for cell-free protein synthesis

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Synthetic and Systems Biotechnology 2020年第3期5卷 145-154页

作者： Marilyn S.Lee chia-Suei Hung daniel A.Phillips chelsea c.Buck Maneesh K.Gupta Matthew W.Lux us Army combat capabilities Development command chemical and Biological center 8567 Ricketts Point RoadAberdeen Proving GroundMD21010USA us Air Force Research Laboratory 217912th St.B652/R122 Wright-Patterson Air Force BaseOH45433USA us Naval Research Laboratory center for Bio/Molecular Science and Engineering Bldg.42Room 3034555 Overlook Ave.WashingtonDC 20375UES Inc.4401 Dayton Xenia Rd.BeavercreekOH 45432USA

cell-free systems contain many proteins and metabolites required for complex functions such as transcription and translation or multi-step metabolic *** into expanding the delivery of these systems by drying or by embedding into other materials is enabling new applications in sensing,point-of-need manufacturing,and responsive ***,silk fibroin from the silk worm,Bombyx mori,has received attention as a protective additive for dried enzyme formulations and as a material to build biocompatible hydrogels for controlled localization or delivery of biomolecular *** this work,we explore the effects of silk fibroin as an additive in cell-free protein synthesis(cFPS)*** of silk fibroin on cFPS activity and stability after drying,as well as the potential for incorporation of cFPS into hydrogels of crosslinked silk fibroin are *** find that simple addition of silk fibroin increased productivity of the cFPS reactions by up to 42%,which we attribute to macromolecular crowding ***,we did not find evidence that silk fibroin provides a protective effects after drying as previously described for purified ***,the enzymatic crosslinking transformations of silk fibroin typically used to form hydrogels are inhibited in the presence of the cFPS reaction *** attempts did not impact cFPS activity,but did yield localized protein aggregates rather than a *** discuss the mechanisms at play in these results and how the silk fibroin-cFPS system might be improved for the design of cell-free devices.

关键词： cell-free systems cell-free protein synthesis cFPS Silk fibroin Preservation