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Disturbance history,species diversity,and structural complexity of a temperate deciduous forest

Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan D.Goode carson R.Barefoot Justin L.Hart daniel c.dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand structural complexity enhancement is an increasingly popular management objective,especially on public *** stand structures are hypothesized to support a relatively high degree of native forest diversity and be more resistant and resilient to *** structures are characterized by the presence of deadwood and heterogeneity of tree-size classes and tree *** little is known about how discrete disturbance events affect structural complexity and compositional diversity in Quercus-dominated stands at fine spatial scales(***).We established 200.05 ha fixed-radius plots on the Sipsey Wilderness of William *** National Forest in northern Alabama to quantify woody plant species composition and *** were mapped on each plot to quantify overstory structural complexity and compositional *** extracted two cores from all canopy Quercus spp.c 5 cm diameter at breast height to quantify age,recruitment pulses,and reconstruct canopy disturbance *** species diversity in the sampled area was 1.75 for trees,2.08 for saplings,and 1.69 for *** alba had the greatest basal area,and Ostrya virginiana had the highest *** stand exhibited a reverse J-shaped distribution with a q-factor of *** oldest Quercus dated to 1795,and the largest recruitment pulse occurred in the *** mean return interval for intermediateseverity disturbance was 38 *** we documented no relationships between disturbance frequency and compositional diversity at the neighborhood scale(0.05 ha),less frequent disturbance was associated with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood *** suggest that localized disturbance increases species diversity and structural complexity,but these processes are manifest at the stand level and not at the neighborhood *** conclude that the spatial variability(***,shape,orientation,microsite conditions)is likel

关键词： canopy gap Quercus(oak) Stand development Succession

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Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

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Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin G.Willson Lauren E.cox Justin L.Hart daniel c.dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Department of Environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an EF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,pcated that understory light penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

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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

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Spatial Variability of Soil Properties and Quality along Different Hillslope Sequences in a Protected Semiarid Oak Forest: the Role of Landscape Position and Shape

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Journal of Earth Science 2023年

作者： Javad cheraghi Mehdi Heydari Mahmood Rostaminia Reza Omidipour Yahya Kooch daniel c.dey Department of soil and water， Faculty of Agriculture， Ilam University，Ilam， Iran Northern Research Station， USDA Forest Service Faculty of Natural Resources & Marine Sciences， Tarbiat Modares University，46417-76489 Noor， Mazandaran Department of Forest Science， Faculty of Agriculture， Ilam University，Ilam， Iran Department of Rangeland and Watershed Management， Faculty of Natural Resources and Earth Sciences， Shahrekord University，Shahrekord， Iran

Forest ecosystems can be characterized by a set of catenas arranged along the slope in mountainous areas because they affect microhabitat features that in turn influence soil properties. Heretofore， limited research has been conducted on the effects of various topographic variables on soil properties and quality in semiarid regions. This study aimed to provide important insights regarding the role of catena position and shape in determining soil properties and soil quality and their relationships in a semiarid protected oak forest in western Iran. Basic soil properties were measured in the laboratory. Finally， the soil quality index (SQI) was calculated at different topographic positions along both convex (Λ-shaped) and concave (V-shaped) catenas and by soil depths (0–15 and 15–30 cm). The findings indicated that soil organic carbon and total nitrogen declined at the lower depth in both V- and Λ-shaped catenas and at all catena positions. The lowest porosity was observed at the lower depth in toeslope positions (TS) in both catenas. Substrate-induced respiration (SIR)， microbial biomass carbon (MBc)， and basal respiration (BR) were higher in the upper depths of TS positions on V-shaped catenas compared to those on Λ-shaped catenas. The level of these biological indices was highest in the upper soil than at lower depths in all positions of both catenas. SQI had the highest values at the TS positions on both catenas and in the upper soil layer for all positions. Pearson correlations between soil properties indicated that SQI for both catenas had the highest significant positive correlation with most soil biological properties. The nutrient levels， microbial activity， and soil porosity in both catena shapes and at both soil depths displayed a relatively downward trend with increasing elevation from toeslope to summit positions. The results showed that catena toposequence shape and position affected most of the soil properties， providing evidence of the important role o

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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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Journal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANDES Letícia RAMOS Dario c.PAIVA Jéssica cUNHA-BLUM Vanessa Matos GOMES daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as chamaecrista choriophylla,cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

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characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina cócola Mercedes Virginia Barros daniel Gregori Leonardo Strazzere Anderson costa dos Santos Mauro c.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%Nacl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions chon Aike geochronology

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comprehensive review of hepatocellular carcinoma with portal vein tumor thrombus:State of art and future perspectives

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 221-227页

作者： Paschalis Gavriilidis Timothy M Pawlik daniel Azoulay Department of Surgery Colchester General HospitalTurner RoadColchester CO45JLUK Department of Surgery The Ohio State Wexner Medical CenterJames Comprehensive Cancer CenterColumbusOHUSA Department of Hepato-Biliary and Liver Transplantation surgery Paul Brousse University HospitalParis-Saclay UniversityVillejuif 94800France

Background:Despite advances in the diagnosis of patients with hepatocellular carcinoma(Hcc),70%-80%of patients are diagnosed with advanced stage *** vein tumor thrombus(PVTT)is among the most ominous signs of advanced stage disease and has been associated with poor survival if *** sources:A systematic search of MEDLINE(PubMed),Embase,cochrane Library and Database for Systematic Reviews(cDSR),Google Scholar,and National Institute for Health and clinical Excellence(NIcE)databases until December 2022 was conducted using free text and MeSH terms:hepatocellular carcinoma,portal vein tumor thrombus,portal vein thrombosis,vascular invasion,liver and/or hepatic resection,liver transplantation,and systematic ***:centers of surgical excellence have reported promising results related to the individualized surgical management of portal thrombus versus arterial chemoembolization or systemic *** elements to the individualized surgical management of Hcc and portal thrombus include precise classification of the portal vein tumor thrombus,accurate identification of the subgroups of patients who may benefit from resection,as well as meticulous surgical *** review addressed five specific areas:(a)formation of PVTT;(b)classifications of PVTT;(c)controversies related to clinical guidelines;(d)surgical treatments versus non-surgical approaches;and(e)characterization of surgical techniques correlated with classifications of ***:current evidence from chinese and Japanese high-volume centers demonstrated that patients with Hcc and associated PVTT can be managed with surgical resection with acceptable results.

关键词： Hepatectomy Liver surgery Liver neoplasms Portal vein tumor thrombus

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Flame Synthesis of Zr/ZSM-5 catalysts with Tunable Acidity for the Oxidative Dehydrogenation of Propane to Propene

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Journal of Thermal Science 2024年第1期33卷 268-283页

作者： daniel Samuel FONZEU MONGUEN cedric Karel WU Lingnan TIAN Zhenyu Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 100049China

Tuning the surface acidity of ZSM-5 catalyst is essential to achieve desired propene selectivity and *** several ratios of Zr were utilized to modify ZSM-5 via flame spray pyrolysis technique coupled with a pulse spray evaporation *** interaction between Zr and ZSM-5 in the flame influenced the physicochemical and acidity properties of the Zr/*** increasing Zr ratio in ZSM-5 shows coated layers of irregular nano-sized Zr with an increase in crystallite sizes due to the synergetic effect between Zr and *** surface chemical analysis revealed increased lattice oxygen on the Zr modified ZSM-5(1:4) sample compared to other *** acidity analysis revealed the Lewis and Br?nsted acid distribution in the weak and medium acid sites on the catalyst ***,the increase in Zr loading decreased the concentration of Br?nsted acid sites and tuned the catalyst surface to more Lewis acidity,promoting propene selectivity and hindering the over-oxidation of *** modified ZSM-5 catalysts were examined in a fixed bed reactor within 300℃-700℃ at a gas hourly space velocity(GHSV) of 6000 mL·g(catalysts)^(-1)·h^(-1) for the oxidative dehydrogenation of propane(ODHP) to *** the catalysts,Zr/ZSM-5(1:4) exhibited the best propene yield, with 57.19% propane conversion and 75.54% selectivity to propene and the highest *** work provides a promising strategy for tuning the surface acidity of ZSM-5 with Zr for ODHP applications.

关键词： flame synthesis Zr modified ZSM-5 catalyst ODHP surface acidity lattice oxygen

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Rapid growth in a large cambrian apex predator

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National Science Review 2024年第3期11卷 128-136页

作者：吴雨 Stephen Pates daniel Pauly 张兴亮傅东静 State Key Laboratory of continental Dynamics and Shaanxi Key Laboratory of Early Life and Environment Department of Geology Northwest University Department of Zoology University of Cambridge Institute for the Oceans and Fisheries University of British Columbia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata, one of the most common radiodont arthropods from the early cambrian chengjiang biota(c. 520 Ma) of china. Analysis of 432 specimens(9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis(ELEFAN) approach. Therefore, we show that the cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory ‘arms race’ that shaped the cambrian explosion over 500 Ma.

关键词： stem-group Euarthropoda Radiodonta post-embryonic development growth dynamics cambrian Explosion

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Twisted fiber microfluidics:a cutting-edge approach to 3D spiral devices

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Microsystems & Nanoengineering 2024年第1期10卷 193-202页

作者： Shunsuke Kato daniel W.carlson Amy Q.Shen Yuanyuan Guo Department of Electrical Information and Physics EngineeringSchool of EngineeringTohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Micro/Bio/Nanofluidics Unit Okinawa Institute of Science and TechnologyOnnaKunigami-gun 904-0495 OkinawaJapan Frontier Research Institute for Interdisciplinary Sciences(FRIS) Tohoku UniversityAoba-kuSendai 980-0845 MiyagiJapan Graduate School of Biomedical Engineering Tohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Department of Physiology Graduate School of MedicineTohoku UniversityAoba-kuSendai 980-8575 MiyagiJapan

The development of 3D spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological *** traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates Dean drag forces,eliminating the necessity for external fields in fluid ***,fabricating 3D spiral microfluidics remains a labor-intensive and costly endeavor,hindering its widespread ***,conventional lithographic methods primarily yield 2D planar devices,thereby limiting the selection of materials and geometrical *** address these challenges,this work introduces a streamlined fabrication method for 3D spiral microfluidic devices,employing rotational force within a miniaturized thermal drawing process,termed as *** innovation allows for rapid prototyping of twisted fiber-based microfluidics featuring versatility in material selection and heightened geometric *** validate the performance of these devices,we combined computational modeling with microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3D flow *** results corroborate the presence of a steady secondary flow,underscoring the effectiveness of our *** 3D spiral microfluidics platform paves the way for exploring intricate microflow dynamics,with promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems.

关键词： thereby straight twisted

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