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

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(boreal latitudes

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

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New insights into protein–polysaccharide complex coacervation:Dynamics,molecular parameters,and applications

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Aggregate 2024年第1期5卷 148-166页

作者： Jiabao Zheng paul Van der Meeren Weizheng Sun School of Food Science and Engineering South China University of TechnologyGuangzhouChina Department of Green Chemistry and Technology Faculty of Bioscience EngineeringGhent UniversityGhentBelgium Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health(111 Center) GuangzhouChina

For more than a decade,the discovery of liquid–liquid phase separation within living organisms has prompted colloid scientists to understand the connection between coacervate functionality,phase behavior,and dynamics at a multidisciplinary *** the protein–polysaccharide was the first system in which the coacervation phenomenon was discovered and is widely used in food systems,the phase state and relaxation dynamics of protein–polysaccharide complex coacervates(PPCC)have rarely been discussed ***,this review aims to unravel the relationship between PPCC dynamics,thermodynamics,molecular architecture,applications,and phase states in past *** ahead,solving the way molecular architecture spreads to macro-functionality,that is,establishing the relationship between molecular architecture–dynamics–application,will catalyze novel advancements in PPCC research within the field of foods and biomaterials.

关键词： dynamics encapsulation liquid coacervate protein-polysaccharide complex coacervation solid precipitate

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A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle J.LAdam H.paul Urbach 袁小聪 Research Center for Humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles

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Associations of accelerometry-measured and self-reported physical activity and sedentary behavior with skeletal muscle energetics:The Study of Muscle,Mobility and Aging(SOMMA)

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Journal of Sport and Health Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri L.blackwell Peggy M.Cawthon paul M.Coen Steven R.Cummings Giovanna Distefano Samaneh Farsijani Daniel E.Forman bret H.Goodpaster Stephen b.Kritchevsky Theresa Mau Frederico G.S.Toledo Anne b.Newman Nancy W.Glynn Department of Epidemiology School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating Center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Department of Epidemiology and biostatistics University of CaliforniaSan FranciscoCA 94143USA Translational Research Institute AdventHealthOrlandoFL 32804USA Department of Medicine(Geriatrics and Cardiology) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Department of Internal Medicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of Endocrinology and Metabolism Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

background:Skeletal muscle energetics decline with age,and physical activity(PA)has been shown to offset these declines in older ***,many studies reporting these effects were based on self-reported PA or structured exercise ***,we examined the associations of accelerometry-measured and self-reported PA and sedentary behavior(Sb)with skeletal muscle energetics and explored the extent to which PA and sedentary behavior would attenuate the associations of age with muscle ***:As part of the Study of Muscle,Mobility and Aging,enrolled older adults(n=879),810(age=76.4±5.0 years old,mean±SD;58%women)had maximal muscle oxidative capacity measured ex vivo via high-resolution re spirometry of permeabilized myofibers(maximal oxidative phosphorylation(maxOXPHOS))and in vivo by ^(31)phosphorus magnetic resonance spectroscopy(maximal adenosine triphosphate(ATP_(max))).Accelerometry-measured sedentary behavior,light activity,and moderate-to-vigorous PA(MVPA)were assessed using a wrist-worn ActiGraph GT9X over 7 ***-reported sedentary behavior,MVPA,and all PA were assessed with the Community Healthy Activities Model Program for Seniors(CHAMPS)*** regression models with progressive covariate adjustments evaluated the associations of sedentary behavior and PA with muscle energetics,as well as the attenuation of the age/muscle energetics association by MVP A and sedentary *** a sensitivity analysis,we also examined activPAL-measured daily step count and time spent in sedentary behavior and their associations with muscle ***:Every 30 min/day more of ActiGraph-measured MVPA was associated with 0.65 pmol/(s×mg)higher maxOXPHOS and 0.012 mM/s higher ATP_(max)after adjusting for age,site/technician,and sex(pbehavior was associated with 0.39 pmol/s×mg lower maxOXPHOS and0.

关键词： Aging Exercise Mitochondria

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boson star superradiance

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 69-78页

作者： He-Yu Gao paul M.Saffin Yi-Jie Wang Qi-Xin Xie Shuang-Yong Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China School of Physics and Astronomy University of NottinghamUniversity ParkNottingham NG72RDUK Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefei 230026China Peng Huanwu Center for Fundamental Theory Hefei 230026China

Recently,it has been realized that in some systems internal space rotation can induce energy amplification for scattered waves,similar to rotation in real *** particularly,it has been shown that energy extraction is possible for a Q-ball,a stationary non-topological soliton that is coherently rotating in its field *** this paper,we generalize the analysis to the case of boson stars,and show that the same energy extraction mechanism still works for boson stars.

关键词： superradiance boson star field space rotation

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Diet and monensin influence the temporal dynamics of the rumen microbiome in stocker and finishing cattle

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Journal of Animal Science and biotechnology 2024年第2期15卷 733-748页

作者： Jianmin Chai Caleb P.Weiss paul A.beck Wei Zhao Ying Li Jiangchao Zhao Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise breeding College of Life Science and EngineeringFoshan UniversityFoshanChina Division of Agriculture Department of Animal ScienceUniversity of ArkansasFayettevilleARUSA Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA Institute of Feed Research of Chinese Academy of Agricultural Sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100193China

background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen *** the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were *** calves were then transported to a feedlot and received similar finishing diets with or without *** microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,Pre-ba,and Final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was *** Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing *** bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were *** treatments during the stocker stage temporally impact the dynamics of rumen *** example,shared bacteria,including bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and F0,while bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in *** affected rumen microbial composition at a specific *** to feedlot significantly influenced microbiome structure and diversity in hay-fed *** taxa associated with body weight were classified,and core microbiotas interacted with each other during the *** In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding *** at the stocker phase may t

关键词： beef cattle Diet Feedlot phase Monensin Next-generation sequencing Rumen microbiota Stocker

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Ab_(2)-type rare earth-based compounds with C-15 structure:Looking for reversible hydrogen storage materials

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Journal of Rare Earths 2024年第5期42卷 803-816,I0001页

作者： Hao Shen Junxian Zhang Valerie paul-boncour Ping Li Zhinian Li Yuanfang Wu Lijun Jiang National Engineering Research Center of Nonferrous Metals Materias and Products for New Energy GRINM Group Co.LtdBeijing00088China Univ Paris Est Creteil CNRSICMPEUMR 71822 rue Henri Dunant94320ThiaisFrance Institute for Advanced Materials and Technology University of Science and TechnologyBeijing100083China GRIMAT Engineering Institute Co. Ltd.Beijing101407China

Ab_(2)-type(A=rare earth,b=transition metal)intermetallic compounds with C15 structure can easily absorb large amount of hydrogen,showing their potential use as hydrogen storage *** crucial problem hindering their application is hydrogen induced amorphization(HIA),which leads to the irreversible hydrogen sorption *** stability of the Ab_2 Laves phase compounds,the structural properties,the hydrogenation properties and the controlling factors of HIA are discussed in this *** with other factors,the atomic radii ratio r_A/r_b is the most important one influencing the ***-element substitution is an efficient way to suppress or limit HIA and may enable Ab_2 compounds to be suitable for hydrogen storage.

关键词： Rare earth-based Ab_2-type compounds Hydrogenation properties Hydrogen induced amorphization Elemental substitution

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Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico

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Forest Ecosystems 2024年第1期11卷 1-13页

作者： Jaime Roberto Padilla-Martínez Carola paul Kai Husmann Jose Javier Corral-Rivas Klaus von Gadow Department of Forest Economics and Sustainable Land-use Planning Faculty of Forest Sciences and Forest EcologyUniversity of GottingenBüsgenweg 137077GottingenGermany Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Boulevard Durango S/N34120DurangoMexico Faculty of Forestry and Forest Ecology Georg-August-UniversitatBüsgenweg 537077GottingenGermany Department of Forestry and Wood Science Faculty of AgriSciencesStellenbosch UniversityStellenbosch Private Bag X1Stellenbosch7602South Africa

Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological ***,a greater species diversity presents challenges for forest management and *** study aims to develop basal area growth models for tree species *** analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,***,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster ***,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site *** principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the *** generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak *** developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests.

关键词： Temperate multispecies forests Cluster analysis basal area increment Generalized additive models

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Synthesis of Unprotectedα-Tertiary Amines and 1,2-Amino Alcohols from Vinyl Azides by Light Induced Denitrogenative Alkylarylation/Dialkylation

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CCS Chemistry 2024年第4期6卷 1060-1070页

作者： Sifan Li Hai-Wu Du paul W.Davies Wei Shu Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen 518055Guangdong School of Chemistry University of BirminghamEdgbastonBirmingham B152TT

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to ***,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been *** use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial *** strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group *** synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted *** investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.

关键词： photocatalysis α-tertiary primary amines 1 2-amino alcohols vinyl azide electron donor-acceptor complex

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Incidence and risk factors for early renal dysfunction after liver transplantation

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World Journal of Transplantation 2016年第1期6卷 220-232页

作者： Patricia Wiesen paul b massion Jean Joris Olivier Detry Pierre Damas Department of General Intensive Care University Hospital of Liege Department of Anaesthesiology and Intensive Care Medicine University Hospital of Liege Department of Abdominal Surgery and Transplantation CHU Liege University of Liege (CHU ULg)

AIM: To determine renal dysfunction post liver transplantation, its incidence and risk factors in patients from a belgian University ***: Orthotopic liver transplantations performed from January 2006 until September 2012 were retrospectively reviewed(n = 187). Patients with no renal replacement therapy(RRT) before transplantation were classified into four groups according to their highest creatinine plasma level during the first postoperative week. The first group had a peak creatinine level below 12 mg/L, the second group between 12 and 20 mg/L, the third group between 20 and 35 mg/L, and the fourth above 35 mg/L. In addition, patients who needed RRT during the first week after transplantation were also classified into the fourth group. Perioperative parameters were recorded as risk factors, namely age, sex, bodymass index(bMI), length of preoperative hospital stay, prior bacterial infection within one month, preoperative ascites, preoperative treatment with β-blocker, angiotensin-converting enzyme inhibitor or non steroidal anti-inflammatory drugs, preoperative creatinine and bilirubin levels, donor status(cardiac death or brain death), postoperative lactate level, need for intraoperative vasopressive drugs, surgical revision, mechanical ventilation for more than 24 h, postoperative bilirubin and transaminase peak levels, postoperative hemoglobin level, amount of perioperative blood transfusions and type of immunosuppression. Univariate and multivariate analysis were performed using logistic ordinal regression method. Post hoc analysis of the hemostatic agent used was also ***: There were 78 patients in group 1(41.7%), 46 in group 2(24.6%), 38 in group 3(20.3%) and 25 in group 4(13.4%). Twenty patients required RRT: 13(7%) during the first week after transplantation. Using univariate analysis, the severity of renal dysfunction was correlated with presence of ascites and prior bacterial infection, preoperative bilirubin, urea and creatinine le

关键词： Liver transplantation Acute kidney injury incidence Perioperative complications Acute kidney injury risk factors Creatinine/blood Severity renal failure

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