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growth trends and environmental drivers of major tree species of the northern hardwood forest of eastern North America

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Journal of Forestry Research 2023年第1期34卷 37-50页

作者： Rebecca L.Stern paul g.schaberg Shelly A.Rayback Christopher F.Hansen paula F.Murakami gary J.Hawley Rubenstein School of Environment and Natural Resources The University of VermontBurlingtonVT 05405USA ERM MalvernPA 19355USA Forest Service United States Department of AgricultureNorthern Research StationBurlingtonVT 05405USA Department of geography The University of VermontBurlingtonVT 05405USA

The future health and productivity of tree species in the northern hardwood forest of eastern North America are uncertain considering changes in climate and pollution loading *** better understand the trajectory of the northern hardwood forest,we studied the growth of three tree species emblematic of it:sugar maple(Acer saccharum Marsh),American beech(Fagus grandifolia Ehrh.),and yellow birch(Betula alleghaniensis Britton),plus a fourth species,red maple(Acer rubrum L.),whose abundance has increased in the *** also analyzed the link between growth and several factors for690 trees in 45 plots throughout Vermont,USA:tree age and size,site elevation,and climate and acid deposition *** their chronologies(1945-2014),all four species exhibited increasing growth followed by plateaued growth indicative of a maturing *** all species,summer moisture was positively correlated with growth,summer temperature was negatively associated with growth,and winter moisture or snow were positively correlated with *** last association was expected for sugar ***,our data suggest that winter snowpack may be more broadly relevant in sustaining tree growth in a region where snow has historically insulated the soil from freezing that can damage roots and lead to reduced aboveground *** of pollution deposition were also correlated with growth for all species except American beech—a species with documented tolerance to pollutant *** the four species studied,red maple had the fewest associations with environmental variables,which suggests that it may be less susceptible to growth reductions as the climate changes.

关键词： Climate change Sugar maple Yellow birch American beech Red maple

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The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David P.g.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(g evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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Pressurized environments directly influence friction and wear of dry steel contacts—Investigations in a novel high fluid pressure tribometer

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Friction 2024年第7期12卷 1599-1617页

作者： paul REICHLE Jakob BARZ georg UMLAUF günter E.M.TOVAR Institute of Interfacial Process Engineering and Plasma Technology(IgVP) University of StuttgartStuttgart 70569Germany Fraunhofer Institute for Interfacial Engineering and Biotechnology(IgB) Stuttgart 70569Germany

To reduce the usage of classical lubricants in deep drawing,a new tribological system based on volatile lubricants was ***,a volatile medium is injected under high pressure into the interstice between drawing tool and sheet *** on temperature and pressure,the temporary lubricant may exist in its gaseous or liquid *** this study,a novel high fluid pressure tribometer was designed to investigate the friction and wear of dry steel contacts under comparable conditions like in dry deep ***,a new ball-on-disc tribometer was designed and integrated into a high-pressure *** specifically investigate the effects of different environments(technical air,liquid and gaseous carbon dioxide,nitrogen,argon)at atmospheric and high pressure(0.1 MPa,6 MPa)on tribology,the specimens and all components were operating *** the experiments,the friction was measured *** show that the highest friction occurs in air and the lowest in carbon dioxide *** to the experiments,the wear of the specimens was assessed along with changes in surface chemistry related to tribochemical ***,the tribology of the dry sliding contacts is correlated to changes of the surface *** differences as well as similarities regarding the different fluid environments are *** the results show,the differences between the media used are most pronounced at elevated ***,this work gives clear indications on the suitability of volatile lubricants in dry friction or rather gas lubrication,especially for dry deep drawing.

关键词： dry friction and dry wear gas lubrication carbon dioxide tribo-layer dry metal forming

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Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang paul Lingor Department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia with Lewy bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,where pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the way to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical

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Improving Heat Transfer in Parabolic Trough Solar Collectors by Magnetic Nanofluids

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Energy Engineering 2024年第4期121卷 835-848页

作者： Ritesh Singh Abhishek gupta Akshoy Ranjan paul Bireswar paul Suvash C.Saha Department of Applied Mechanics Motilal Nehru National Institute of Technology AllahabadPrayagrajIndia Department of Mechanical and Mechatronic Engineering University of Technology SydneySydneyAustralia

A parabolic trough solar collector(PTSC)converts solar radiation into thermal ***,low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power *** performance of PTSC is enhanced in this study by incorporating magnetic nanoparticles into the working *** circular receiver pipe,with dimensions of 66 mm diameter,2 mm thickness,and 24 m length,is exposed to uniform temperature and velocity *** working fluid,Therminol-66,is supplemented with Fe3O4 magnetic nanoparticles at concentrations ranging from 1%to 4%.The findings demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTC)of the PTSC,with higher nanoparticle volume fractions leading to greater heat transfer but increased pressure *** thermal enhancement factor(TEF)of the PTSC is positively affected by the volume fraction of nanoparticles,both with and without a magnetic ***,the scenario with a 4%nanoparticle volume fraction and a magnetic field strength of 250 g exhibits the highest TEF,indicating superior thermal *** findings offer potential avenues for improving the efficiency of PTSCs in solar thermal plants by introducing magnetic nanoparticles into the working fluid.

关键词： Parabolic trough solar collector(PTSC) magnetic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTC) thermal enhancement factor(TEF)

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Exploring innovative synthetic solutions for advanced polymer-based electrochromic energy storage devices:Phenoxazine as a promising chromophore

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Journal of Energy Chemistry 2024年第4期91卷 433-452页

作者： Catalin-paul Constantin Mihaela Balan-Porcarasu gabriela Lisa “Petru Poni”Institute of Macromolecular Chemistry Electroactive Polymers&Plasmochemistry Laboratory41A Grigore Ghica Voda AlleyIasi 700487Romania “gh.Asachi”Technical University Iasi Faculty of Chemical EngineeringBd.Mangeron 71Iasi 700050Romania

The current investigation offers an innovative synthetic solution regarding electrochromic(EC)and energy storage applications by exploring phenoxazine(POZ)***,three POZ-based polymers(polyimide,polyazomethine,and polyamide)were synthesized to ascertain the superior *** polyamide exhibited remarkable attributes,including high redox stability during 500 repetitive CVs,optical contrast of 61.98%,rapid response times of 1.02 and 1.38 s for coloring and bleaching,EC efficiency of 280 cm^(2)C^(-1).and decays of the optical density and EC efficiency of only 12.18%and 6.23%after 1000 ***,the energy storage performance of polyamide PA was tested,for which the following parameters were obtained:74.7 F g^(-1)(CV,scan rate of 10 mV s^(-1))and 118 F g^(-1)(gCD,charging current of 0.1 A g^(-1)).Then,the polyamide was tested in EES devices,which yielded the following EC parameters:an optical contrast of 62.15%,response times of 9.24 and 5.01 s for coloring and bleaching,EC efficiency of 178 cm^(2)C^(-1),and moderate decays of 20.25%and 23.24%for the optical density and EC efficiency after 500 *** energy storage performance included a capacitance of 106 F g^(-1)(CV,scan rate of 0.1 mV s^(-1))and 9.23 F g^(-1)(gCD,charging current of 0.1 A g^(-1)),capacitance decay of 11.9%after500 cycles,and 1.7 V retention after 2 ***,two EES devices connected in series powered a 3 V LED for almost 30 s.

关键词： Polymers Phenoxazine Electrochromic Energy storage Electrochromi cenergy storage devices

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Hypoxic and temporal variation in the endocrine disrupting toxicity of perfluorobutanesulfonate in marine medaka(Oryzias melastigma)

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Journal of Environmental Sciences 2024年第2期136卷 279-291页

作者： Baili Sun Jing Li Yachen Bai Xiangzhen Zhou paul K.S.Lam Lianguo Chen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China Office of the President Hong Kong Metropolitan University30 Good Shepherd StreetKowloonHong Kong SARChina

Perfluorobutanesulfonate(PFBS)is an emerging pollutant capable of potently disrupting the sex and thyroid endocrine systems of ***,the hypoxic and temporal variation in PFBS endocrine disrupting toxicity remain largely *** the present study,adult marine medaka were exposed to environmentally realistic concentrations of PFBS(0 and 10μg/L)under normoxia or hypoxia conditions for 7 days,aiming to explore the interactive behavior between PFBS and *** addition,PFBS singular exposure was extended till 21days under normoxia to elucidate the time-course progression in PFBS *** results showed that hypoxia inhibited the growth and caused the suspension of egg spawn regardless of PFBS *** regard to the sex endocrine system,7-day PFBS exposure led to an acute stimulation of transcriptional profiles in females,which,subsequently,recovered after the 21-day *** potency of hypoxia to disturb the sex hormones was much stronger than PFBS.A remarkable increase in estradiol concentration was noted in medaka blood after hypoxia *** in sex endocrinology of coexposed fish were largely determined by hypoxia,which drove the formation of an estrogenic *** further enhanced the endocrine disrupting effects of ***,the hepatic synthesis of vitellogenin and choriogenin,two commonly used sensitive biomarkers of estrogenic activity,failed to initiate in response to the estrogen *** to sex endocrine system,disturbances in thyroidal axis by PFBS or hypoxia were relatively ***,the present findings will advance our toxicological understanding about PFBS pollutant under the interference of hypoxia.

关键词： Perfluorobutanesulfonate(PFBS) Aquatic hypoxia Temporal toxicity Combined exposure Endocrine disruption Marine medaka

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An Autopsy and Histopathology-based Study to Ascertain the Cause of Death of Brought Dead Cases

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Journal of Forensic Science and Medicine 2024年第1期10卷 28-33页

作者： Chandan Bandyopadhyay Prabir Chandra paul Prabhas Chandra Chakraborty Department of Forensic and State Medicine Medical CollegeKolkataWest BengalIndia Department of Pathology Jagannath Gupta Institute of Medical Science and HospitalKolkataWest BengalIndia Department of Forensic Medicine and Toxicology NRS Medical College and HospitalKolkataand M.G.M Medical College and L S.K HospitalKishanganjBiharIndia

Background and Objectives:The cases of apparent natural deaths are encountered in the hospital casualties who are noted dead at the time of the first medical attention and as such are labeled as“Brought Dead.”These include the cases of sudden death,unexplained death,and unattended *** cause of such deaths is reported in the literature to emanate principally from the cardiovascular system,though there are some documented geographical,racial,and other *** the present study,we endeavored to detect the cause of such natural deaths in terms of the disease and the organ system involved,in the deceased individuals of the contemporary Bengali population,with cases due to obvious unnatural causes being *** and Methods:An observational,cross-sectional study with 105(n=105,male:89,female:16)study subjects of age group of 20-80 years,selected by systemic random sampling,from the brought dead subjects coming to the mortuary of the NRS Medical College and Hospital for medicolegal autopsy from April 2011 to March 2012,excluding cases having a history of the obvious unnatural *** system-wise gross examination was done,followed by tissue sampling for histopathological *** case-wise findings were tabulated and analyzed for descriptive statistics using SPSS ***:In the present study,89 cases were male(84.8%)and 16 cases were female(15.2%),which reflects a male:female ratio of 5.56:*** dead bodies are mostly recovered from the footpaths(47 cases,44%).Sixty-four(61%)cases are of known *** 54 cases out of 105(51.4%),morbid pathology is detected in the respiratory system(RS),lobar pneumonia,and cavitary pulmonary tuberculosis being the most frequent disease entity,in both ***-one years-sixty-five years is found to be the most commonly affected age group,in both *** and Conclusions:The present study shows that the most common organ system involved in brought dead cases is the RS,which is s

关键词： Autopsy brought dead cause of death histopathology

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Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting

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International Journal of Extreme Manufacturing 2024年第1期6卷 340-351页

作者： Yang Sha Menghui Zhu Kun Huang Yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng paul Mativenga Zhu Liu Department of Materials School of Natural SciencesThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Laser Processing Research Centre Department of MechanicalAerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom National graphene Institute The University of ManchesterOxford RoadManchester M139PLUnited Kingdom Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Research Centre for Laser Extreme Manufacturing Ningbo Institute of Materials Engineering and TechnologyChinese Academy of SciencesNingboPeople’s Republic of China

Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water *** address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of ***,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE *** electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·*** the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially *** addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water *** combination exhibits excellent durability under industrial current *** energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal *** LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production.

关键词： electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate

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Novel wild edible mushroom Astraeus hygrometricus(Pers.)Morgan induces robust apoptosis on human acute lymphoblastic leukemia cells through a RONS-subsisted mitochondria-dependent pathway

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Journal of Traditional Chinese Medical Sciences 2024年第1期11卷 67-77页

作者： Amrita Pal Ribhu Ray Anirban Chouni Subhadip Hajra Santanu paul Department of Botany University of CalcuttaKolkata 700019India Department of Cancer Chemoprevention Chittaranjan National Cancer InstituteKolkata 700026India

Objective:To explore the therapeutic effects of the novel wild edible mushroom Astraeus hygrometricus(Pers.)Morgan(***)on human acute lymphoblastic leukemia ***:Extensive screening of the antiproliferative and chemopreventive potential of different extracts from 5 wild mushrooms,***,Phallus sp.,Lentinus sp.,Tricholoma sp.,and Serpula *** performed against a panel of 6 cancer cell lines and normal cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)*** determination,cell cycle profiling,intracellular reactive oxygen species(ROS)and reactive nitrogen species(RNS),and mitochondrial membrane potential were analyzed by flow *** activity of caspases was measured colorimetrically,and the expression pattern of mitochondrial proteins was ***:The methanol extract of *** and MOLT-4 cells were identified as the most potent extract exhibiting antiproliferative activity and most sensitive cell line,*** mushroom extract induced robust selective apoptosis in MOLT-4 cells and arrested cell cycle progression at the g0/g1 *** extract disrupted the mitochondrial membrane potential and enhanced ROS production in MOLT-4 *** methanol extract induced apoptosis by downregulating the expression of Bcl-2,increasing the expression of Bax,and activating the caspase ***:The novel wild edible mushroom is a potential repository of biomolecules for the development of antileukemic drugs.

关键词： Mushroom Astraeus hygrometricus(Pers.)Morgan Apoptosis Antileukemic

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