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Theory and classification of mass extinction causation

National Science review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun Shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

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COVID-19 vaccination produces exercise-responsive SArS-CoV-2 specific T-cells regardless of infection history

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journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.Zúñiga Forrest L.Baker Helena Batatinha Charles r.Pedlar Shane C.Burgess Michael P.Gustafson Emmanuel Katsanis richard j.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of Pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and Comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Arizona Cancer Center The University of ArizonaTucsonAZ 85719USA Laboratory Medicine and Pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of Pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SArS-CoV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(COVID-19).We sought to determine if COVID-19 vaccination would elicit exercise-responsive SArS-CoV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a COVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SArS-CoV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TCr)-βsequencing,and SArS-CoV-2 nAb ***:COVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of CD4+and CD8+naive T-cells,as well as CD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SArS-CoV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SArS-CoV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SArS-CoV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral COVID-19 Exercise immunology SArS-CoV-2 T-Cells Vaccine

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An analytical model to estimate the time delay to reach spontaneous ignition considering heat loss in oil reservoirs

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Petroleum Science 2024年第4期21卷 2469-2474页

作者： james j.Sheng Er-Long Yang College of Petroleum Engineering Northeast Petroleum University

During air injection into an oil reservoir, an oxidation reaction generates some heat to raise the reservoir temperature. When the reservoir temperature reaches an ignition temperature, spontaneous ignition occurs. There is a time delay from the injection to ignition. There are mixed results regarding the feasibility of spontaneous ignition in real-field projects and in laboratory experiments. No analytical model is available in the literature to estimate the oxidation time required to reach spontaneous ignition with heat *** paper discusses the feasibility of spontaneous ignition from theoretical points and experimental and field project observations. An analytical model considering heat loss is proposed. Analytical models with and without heat loss investigate the factors that affect spontaneous ignition. Based on the discussion and investigations, we find that it is more difficult for spontaneous ignition to occur in laboratory experiments than in oil reservoirs; spontaneous ignition is strongly affected by the initial reservoir temperature, oil activity, and heat loss; spontaneous ignition is only possible when the initial reservoir temperature is high, the oil oxidation rate is high, and the heat loss is low.

关键词： Spontaneous ignition Time delay Air injection Heat loss Low temperature oxidation Combustion

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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils

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journal of Electromagnetic Analysis and Applications 2024年第2期16卷 11-23页

作者： Belemdara Dingamadji Hilaire Mbaïnaïbeye jérôme Guidkaya Golam Department of Physics and Engineering Sciences University of N&#8217Djamena N&#8217Djamena Chad Department of Physics University of Moundou Moundou Chad Department of Physics University of Ngaoundere Ngaoundere Cameroon

The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet.

关键词： Modelling 3D Finite Elements Magnetic Flux Hybrid Stepping Motor

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Intelligent Detection and Identification of Attacks in IoT Networks Based on the Combination of DNN and LSTM Methods with a Set of Classifiers

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Open journal of Applied Sciences 2024年第8期14卷 2296-2319页

作者： Brou Médard Kouassi Vincent Monsan Kablan jérôme Adou Department of Mathematics and Computer Science University Felix Houphouet-Boigny Abidjan Cte dIvoire

Internet of Things (IoT) networks present unique cybersecurity challenges due to their distributed and heterogeneous nature. Our study explores the effectiveness of two types of deep learning models, long-term memory neural networks (LSTMs) and deep neural networks (DNNs), for detecting attacks in IoT networks. We evaluated the performance of six hybrid models combining LSTM or DNN feature extractors with classifiers such as random Forest, k-Nearest Neighbors and XGBoost. The LSTM-rF and LSTM-XGBoost models showed lower accuracy variability in the face of different types of attack, indicating greater robustness. The LSTM-rF and LSTM-XGBoost models show variability in results, with accuracies between 58% and 99% for attack types, while LSTM-KNN has higher but more variable accuracies, between 72% and 99%. The DNN-rF and DNN-XGBoost models show lower variability in their results, with accuracies between 59% and 99%, while DNN-KNN has higher but more variable accuracies, between 71% and 99%. LSTM-based models are proving to be more effective for detecting attacks in IoT networks, particularly for sophisticated attacks. However, the final choice of model depends on the constraints of the application, taking into account a trade-off between accuracy and complexity.

关键词： Internet of Things Machine Learning Attack Detection jamming Deep Learning

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Particle elasticity influences polymeric artificial antigen presenting cell effectiveness in vivo via CD8+T cell activation,macrophage uptake,and the protein corona

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Nano research 2024年第10期17卷 9052-9064页

作者： Savannah E.Est-Witte Sydney r.Shannon Dennis H.Gong Kaitlyn G.Calabresi jawaun j.Harris Kaitlyn Storm Edwin j.Yoo Ariel Isser Vivek P.jani Natalie K.Livingston Mary O.Omotoso Kelly rhodes Elana Ben-Akiva randall A.Meyer Zoe T.Hsieh Simone Sidoli Stephany Y.Tzeng jonathan P.Schneck jordan j.Green Translational Tissue Engineering Center Institute for NanobiotechnologyDepartment of Biomedical EngineeringJohns Hopkins School of Medicine400 N BroadwayBaltimoreMD 21231USA Institute for Cell Engineering Department of PathologyJohns Hopkins School of Medicine733 N BroadwayBaltimoreMD 21205USA Department of Biochemistry Albert Einstein College of MedicineThe BronxNew York CityNY 10461USA

Adoptive cell therapy(ACT)is an immunotherapy strategy for cancer that has seen widespread clinical *** ACT,patient-derived lymphocytes are stimulated with the antigen of interest ex vivo,proliferated,then returned to the patient to initiate an antigen-specific antitumor *** effective,this process is resource-intensive and logistically impossible for many *** artificial antigen presenting cells(aAPCs)offer a potential“off-the-shelf”alternative to ex vivo *** particulate aAPCs perform well in vitro,they have had limited success in vivo due to poor bioavailability after *** to bioavailability include rapid clearance,unfavorable biodistribution,and inadequate interactions with CD8+T cells at sites of *** properties such as elasticity have been shown to vastly impact the bioavailability and particle-cell interactions,but this has yet to be investigated in the context of aAPCs for in vivo T-cell *** literature likewise indicates that biomaterial properties,especially elasticity,can modulate T-cell activation in *** the goal of creating a more biomimetic,next-generation particulate aAPC,we developed a poly(ethylene)glycol hydrogel particle platform with tunable elasticity to investigate the impact of elasticity on antigen-specific T cell activation for in vivo adoptive *** this knowledge,we were able to gain more precise control over in vivo T cell activation and investigate possible mechanisms including the effects of aAPC elasticity on T cell binding,macrophage uptake,and the protein corona.

关键词： adoptive cell therapy artificial antigen presenting cells particle drug delivery elasticity protein corona poly(ethylene glycol)

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Evaluating reservoir suitability for large-scale hydrogen storage:A preliminary assessment considering reservoir properties

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Energy Geoscience 2024年第4期5卷 198-211页

作者： Chinedu j.Okere james j.Sheng Chinedu Ejike Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX79409United States Mewbourne School of Petroleum and Geological Engineering University of OklahomaOK73019United States

With rising demand for clean energy,global focus turns to finding ideal sites for large-scale underground hydrogen storage(UHS)in depleted petroleum reservoirs.A thorough preliminary reservoir evaluation before hydrogen(H_(2))injection is crucial for UHS success and *** criteria for UHS often emphasize economics and chemistry,neglecting key reservoir *** study introduces a comprehensive framework for the reservoir-scale preliminary assessment,specifically tailored for long-term H_(2) storage within depleted gas *** evaluation criteria encompass critical components,including reservoir geometry,petrophysical properties,tectonics,and formation *** illustrate the practical application of this approach,we assess the Barnett shale play reservoir *** assessment unfolds through three key stages:(1)A systematic evaluation of the reservoir's properties against our comprehensive screening criteria determines its suitability for H_(2) storage.(2)Using both homogeneous and multilayered gas reservoir models,we explore the feasibility and efficiency of H_(2) *** phase involves an in-depth examination of reservoir behavior during the injection stage.(3)To enhance understanding of UHS performance,sensitivity analyses investigate the impact of varying reservoir dimensions and injection/production *** findings reveal the following:(a)Despite potential challenges associated with reservoir compaction and aquifer support,the reservoir exhibits substantial promise as an H_(2) storage site.(b)Notably,a pronounced increase in reservoir pressure manifests during the injection stage,particularly in homogeneous reservoirs.(c)Furthermore,optimizing injection-extraction cycle efficiency can be achieved by augmenting reservoir dimensions while maintaining a consistent *** ensure a smooth transition to implementation,further comprehensive investigations are advised,including experimental and numerical studies to address

关键词： Site selection Underground hydrogen storage Preliminary evaluation Depleted petroleum reservoirs reservoir assessment

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rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:Value of tailored peri-pancreatectomy protocols

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World journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich Elijah Dixon Parul j Shukla Shailesh V Shrikhande rahul r Deshpande Fawwaz Mohammed Neil W Pearce Wesley Francis Shaneeta johnson johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGrOUND Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-latively high risk for *** ability to rescue patients from post-PD complications is as a recognized quality *** protocols were instituted at our low volume facility in the year *** To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of *** A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between january 1,2013 and june 30,***-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD *** Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this *** complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).Twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their ***(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).CONCLUSION This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring *** low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major *** attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adaptive learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protoc

关键词： Pancreas Complication rescue Failure Morbidity Mortality Pancreaticoduodenectomy

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Mid-term survival of the Optimys short stem: A prospective case series of 500 patients

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World journal of Orthopedics 2024年第3期15卷 257-265页

作者： Bryan Hamans Sheryl de Waard Sjoerd Kaarsemaker Esther r C janssen Inger N Sierevelt Gino M M j Kerkhoffs Daniël Haverkamp Department of Orthopaedic Surgery Xpert ClinicAmsterdam 1101EANetherlands Department of Orthopedic Surgery Amsterdam University Medical CenterAmsterdam 1105 AZNetherlands Esther r C janssen Department of Orthopaedic SurgeryViecuri Medisch CentrumVenlo 5912 BLNetherlands Centre for Orthopaedic research Spaarne ZiekenhuisHoofddorp 2134 TMNetherlands Department of Orthopaedic Surgery and Sports Medicine Amsterdam UMC-Location AMCAmsterdam 1105 AZNetherlands Department of Orthopedic Surgery Xpert Orthopedic Surgery ClinicAmsterdam 1101 EANetherlands

BACKGrOUND In recent years,there has been an increase in the number of total hip arthroplasty procedures in the younger patient *** active group has higher expectations of their prosthesis in comparison to the older population,and there is a greater physical demand for the *** femoral stems were in-troduced to retain proximal bone stock and joint biomechanics and became more common to implant in this specific ***,the long-term survival and functional outcomes of various short stems are still being investigated in different *** To determine the 5-year survival of the Optimys hip *** This was a prospective multicenter cohort study of 500 patients conducted in two hospitals in the *** patients received the Optimys short stem(Mathys Ltd,Bettlach,Switzerland).The primary outcome measure was survival of the hip stem,with revision as the *** secondary outcome measurements included patient-reported outcome measures(PrOMs).Kaplan-Meier analysis was used to calculate the 5-year survival ***-minus-log transformation was performed to calculate the 95%confidence interval(95%CI).Mixed model analyses were performed to assess the course of the PrOMs during the 1st 2 years after *** were modeled separately for the 1st and 2nd years to calculate the yearly change in PrOMs during both follow-up periods with accompanying 95%*** The mean age of the total 500 patients was 62.3 years(standard deviation:10.6)and 202 were male(40%).At a median follow-up of 5.5 years(interquartile range:4.5-6.7),7 patients were deceased and 6 revisions were registered,for infection(n=3),subsidence(n=2)and malposition(n=1).This resulted in an overall 5-year survival of 98.8%(95%CI:97.3-99.5).If infection was left out as reason for revision,a stem survival of 99.4%(95%CI:98.1-99.8)was *** questionnaires were completed by 471 patients(94%),317 patients(63%)completed the 1-year follow-up questionna

关键词： Total hip arthroplasty Femoral stem Short stem Optimys Survival 5-year survival revision PrOMs

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In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

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Particuology 2024年第3期86卷 304-312页

作者： Simon Aβmann Franz j.T.Huber Stefan Will Lehrstuhl für Technische Thermodynamik(LTT) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical Technologies(SAOT) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(TTIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of TTIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution

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