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Wildfire severity alters soil microbial exoenzyme production and fungal abundances in the southern Appalachian mountains

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Pedosphere 2024年第5期34卷 865-878页

作者： megan l.SCHIll Richard BAIRD Shawn P.BROWN Allison m.VEACH Department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University Department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

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Empirical model for fusion cross sections of Ca-induced reactions

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Chinese Physics C 2024年第3期48卷 126-132页

作者： Reddi Rani.l N.Sowmya K.N Sridhar H C.manjunatha m.m.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical formula for the astrophysical S-factor has been suggested as a function of the Coulomb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)Ca as projectiles were considered for different targets,leading to compound nuclei with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfield factor,and the empirical formula for the *** study's findings showed better agreement with those of available experiments when compared to Wong's *** present work leads to a smaller standard deviation value than Wong's formula when used to correlate the experimental data of calcium-induced fusion ***'s formula provides a good approximation of fusion cross-sections when the center of mass energy is below the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formula Gamow-Sommerfield-factor Geometric-factor S-factor

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Design of a multi-Stage Ensemble model for Thyroid Prediction Using learning Approaches

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Intelligent Automation & Soft Computing 2024年第1期39卷 1-13页

作者： m.l.maruthi Prasad R.Santhosh Department of Computer Science and Engineering Faculty of EngineeringKarpagam Academy of Higher EducationCoimbatoreTamil NaduIndia

This research concentrates to model an efficient thyroid prediction approach,which is considered a baseline for significant problems faced by the women *** major research problem is the lack of automated model to attain earlier *** existing model fails to give better prediction ***,a novel clinical decision support system is framed to make the proper decision during a time of *** stages are followed in the proposed framework,which plays a substantial role in thyroid *** steps include i)data acquisition,ii)outlier prediction,and iii)multi-stage weight-based ensemble learning process(mS-WEl).The weighted analysis of the base classifier and other classifier models helps bridge the gap encountered in one single classifier *** classifiers aremerged to handle the issues identified in others and intend to enhance the prediction *** proposed model provides superior outcomes and gives good quality prediction *** simulation is done in the mATlAB 2020a environment and establishes a better trade-off than various existing *** model gives a prediction accuracy of 97.28%accuracy compared to other models and shows a better trade than others.

关键词： Thyroid machine learning pre-processing classification prediction rate

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In situ TEm investigation of electron irradiation and aging-induced high-density nanoprecipitates in an mg-10Gd-3Y-1Zn-0.5Zr alloy

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Journal of magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： m.lv H.l.Ge Q.Q.Jin X.H.Shao Y.T.Zhou B.Zhang X.l.ma Shenyang National laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： mg alloy Electron beam irradiation Hardening Precipitates In-situ TEm

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Greatly enhanced corrosion/wear resistances of epoxy coating for mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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Journal of magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.li J.H.Chu m.m.li D.N.Zou l.B.Tong School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key laboratory of Advanced Design and manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of mg alloys.

关键词： mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

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Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power laser Science and Engineering 2024年第3期12卷 134-145页

作者： m.Füle A.P.Kovács T.Gilinger m.Karnok P.Gaál S.Figul G.marowsky K.Osvay National laser-Initiated Transmutation laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ElI AlPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

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The secondary injury cascade after spinal cord injury:an analysis of local cytokine/chemokine regulation

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Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： Daniel J.Hellenbrand Charles m.Quinn Zachariah J.Piper Ryan T.Elder Raveena R.mishra Taylor l.marti Phoebe m.Omuro Rylie m.Roddick Jae Sung lee William l.murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public HealthMadisonWIUSA Department of Biomedical Engineering University of Wisconsin-MadisonMadisonWIUSA Department of Orthopedics and Rehabilitation University of Wisconsin-MadisonMadisonWIUSA Department of materials Science and Engineering University of Wisconsin-MadisonMadisonWIUSA Forward BIO Institute University of Wisconsin-MadisonMadisonWIUSA

After spinal cord injury,there is an extensive infiltration of immune cells,which exacerbates the injury and leads to further neural ***,a major aim of current research involves targeting the immune response as a treatment for spinal cord *** much research has been performed analyzing the complex inflammatory process following spinal cord injury,there remain major discrepancies within previous literature regarding the timeline of local cytokine *** objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury,identify sexual dimorphisms in terms of cytokine levels,and determine local cytokines that significantly change based on the severity of spinal cord *** were inflicted with either a mild contusion,moderate contusion,severe contusion,or complete transection,7 mm of spinal cord centered on the injury was harvested at varying times post-injury,and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex *** demonstrated pro-inflammatory cytokines including tumor necrosis factorα,interleukin-1β,and interleukin-6 were all upregulated after spinal cord injury,but returned to uninjured levels within approximately 24 hours post-injury,while chemokines including monocyte chemoattractant protein-1 remained upregulated for days *** contrast,several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days *** spinal cord injury,tissue inhibitor of metalloproteinase-1,which specifically affects astrocytes involved in glial scar development,increased more than all other cytokines tested,reaching 26.9-fold higher than uninjured *** a mild injury,11 cytokines demonstrated sexual dimorphisms;however,after a severe contusion only leptin levels were different between female and male *** conclusion,pro-inflammatory cytokines in

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

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Post-fire recovery of Puya raimondii, vegetation and birds in the puna of Huascarán National Park, Perú

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Journal of mountain Science 2024年第1期21卷 20-32页

作者： mery l.SUNI Giovana P.VADIllO César ARANA Enoc JARA-PENA letty SAlINAS m.Estela PONCE Paul m.RAmSAY Plant Physiology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Natural History museum Universidad Nacional Mayor de San MarcosLima 15072Peru Applied Phytology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Statistics Faculty of Mathematical SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Chemical and Biological Sciences Universidad de las Américas PueblaSan Andrés Cholula CP Cholula CP 72810Mexico

A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.

关键词： Burning Plant biomass Trophic guilds Andes Giant rosette plants

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A Theoretically Grounded Question Answering Data Set for Evaluating machine Common Sense

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Data Intelligence 2024年第1期6卷 1-28页

作者： Henrique Santos Ke Shen Alice m.mulvehill mayank Kejriwal Deborah l.mcGuinness Rensselaer Polytechnic Institute Troy NY Information Sciences Institute Marina del Rey CA

Achieving machine common sense has been a longstanding problem within Artificial *** far,benchmark data sets that are grounded in a theory of common sense and can be used to conduct rigorous,semantic evaluations of common sense reasoning(CSR)systems have been *** expectation of the AI community is that neuro-symbolic reasoners can help bridge this gap towards more dependable systems with common *** propose a novel benchmark,called Theoretically Grounded common sense Reasoning(TG-CSR),modeled as a set of question answering instances,with each instance grounded in a semantic category of common sense,such as space,time,and *** benchmark is few-shot i.e.,only a few training and validation examples are provided in the public release to avoid the possibility of *** from recent evaluations suggest that TG-CSR is challenging even for state-of-the-art statistical *** to its semantic rigor,this benchmark can be used to evaluate the common sense reasoning capabilities of neuro-symbolic systems.

关键词： reasoning Intelligence instance

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Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.madhu H.C.manjunatha N.Sowmya B.m.Rajesh l.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)Cr+^(243)Am,23.2 fb at 236 meV for ^(54)Cr+^(247)Cm,95.6 fb at 240 meV for ^(53)Cr+248Bk,and 1.33 fb at 242 meV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

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