检索结果-南通市图书馆

国外煤田地质 1989年第1期 24-28页

作者： danie.,j.薛忍霞

The Generalized Stackelberg Equilibrium of the Two-Person Stopping Game

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of the Operations Research Society of China 2024年第1期12卷 155-168页

作者： Marek Skarupski Krzysztof j.Szaj.wski Faculty of Pure and Applied Mathematics Wroclaw University of Science and Technology50-370WrocƚawDolonoslaskiePoland

In modeling the bilateral selection of states of the process,Dynkin(Dokl Akad Nauk USSR 185:241–288,1969)proposed a two-person game in which players use stopping moments as *** purpose of this work is to present a model of the game in which the players have different information about the process itself,as well as various laws to stop the process and accept its *** game model uses the stochastic process apparatus,in particular,the ability to create different filters for the same *** sets of stopping moments based on different filters are not identical,which allows us to model different sets of strategies for *** show that the follower,by observing the behavior of a rational leader,can recover information that is lost due to the lack of complete observation of the state of the *** the competition of two opponents for the maximum of the ***,one of whom has access to full information and the other only knows their relative ranks,we found the generalized Stackelberg *** the priority of a player observing the relative ranks is less than 50%,then that player modifies his strategy based on the behavior of the second *** a player with full information,information about the behavior of the player observing the relative ranks is useless.

关键词： No-zero-sum game Optional stopping Equilibrium Filtration

Extracellular vesicles and angiotensin-converting enzyme 2 in COVID-19 disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BIOCELL 2024年第1期48卷 1-8页

作者： YU LIU ROBERT j.KASPER NATALIE j.S.CHOI Department of Family and Community Medicine Northwestern University Feinberg School of MedicineChicagoIllinois

Extracellular vesicles(EVs)are membranous vesicular structures released from almost all eukaryotic cell types under different physiological or pathological *** evidence demonstrates that EVs can serve as mediators of intercellular communication between donor and recipient cells or microorganism-infected and noninfected *** disease 2019(COVID-19)disease is caused by infection of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)of host cells in the respiratory system and various extra-pulmonary tissue/organs,resulting in complications of multiple organ *** the cell surface receptor,angiotensin-converting enzyme 2(ACE2)mediates cellular entry of SARS-CoV-2 into the host cells in patients with *** studies have found that ACE2 can be released with EVs,which have been shown to interfere with the entry of the virus into host cells and thus may be involved in COVID-19 *** addition,ACE2,neprilysin(NEP),and thimet oligopeptidase(TOP)are the key enzymes that regulate angiotensin metabolism by converting angiotensin II or angiotensin I to angiotensin 1-7,the latter of which has protective effects in counterbalancing the harmful effects of angiotensin II in COVID-19 *** review summarizes the recent research progress regarding EV-associated ACE2,NEP,and TOP and the perspectives of their potential involvement in the pathophysiology of COVID-19 disease.

关键词： Extracellular vesicles COVID-19 Angiotensin converting enzyme 2 Thimet oligopeptidase

Invasive ant learning is not affected by seven potential neuroactive chemicals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2024年第1期70卷 87-97页

作者： Henrique Galante Tomer j.Czaczkes Department of Zoology and Evolutionary Biology Animal Comparative Economics LaboratoryUniversity of Regensburg93053 Regensburg Germany

Argentine ants Linepithema humile are one of the most damaging invasive alien species *** or disrupting cognitive abilities,such as learning,has the potential to improve management efforts,for example by increasing preference for a bait,or improving ants'ability to learn its characteristics or ***-feeding insects are often the victims of psychoactive manipulation,with plants lacing their nectar with secondary metabolites such as alkaloids and non-protein amino acids which often alter learning,foraging,or ***,the effect of neuroactive chemicals has seldomly been explored in ***,we test the effects of seven potential neuroactive chemicals-two alkaloids:caffeine and nicotine;two biogenic amines:dopamine and octopamine,and three nonprotein amino acids:β-alanine,GABA and taurineon the cognitive abilities of invasive *** using bifurcation *** results confirm that these ants are strong associative learners,requiring as little as one experience to develop an ***,we show no short-term effect of any of the chemicals tested on spatial learning,and in addition no effect of caffeine on short-term olfactory *** lack of effect is surprising,given the extensive reports of the tested chemicals affecting learning and foraging in *** mismatch could be due to the heavy bias towards bees in the literature,a positive result publicationbias,ordifferences inmethodology.

关键词： associativelearning caffeine memory neuroactivechemicals

A Study of the TPS Based Beam-Matching Concept for Medical Linear Accelerators at a Tertiary Hospital

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International j.urnal of Medical Physics, Clinical Engineering and Radiation Oncology 2024年第1期13卷 16-25页

作者： Ntombela N. Lethukuthula Rovetto j. Nicolas Nethwadzi C. Lutendo Mpumelelo Nyathi Department of Radiation Oncology Steve Biko Academic Hospital Pretoria South Africa Department of Medical Physics University of Pretoria Pretoria South Africa Department of Medical Physics Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy can be improved if patients can be moved between any one of the department’s medical linear accelerators (LINACs) without the need to change anything in the patient’s treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must be the same, or nearly the same. The purpose of this work is to describe further and compare measurements and parameters after the initial vendor-recommended beam matching of the five LINACs. Deviations related to dose calculations and to beam matched accelerators may compromise treatment accuracy. The safest and most practical way to ensure that all accelerators are within clinical acceptable accuracy is to include TPS calculations in the LINACs matching evaluation. Treatment planning system (TPS) was used to create three photons plans with different field sizes 3 × 3 cm, 10 × 10 cm and 25 × 25 cm at a depth of 4.5 cm in Perspex. Calculated TPS plans were sent to Mosaiq to be delivered by five LINACs. TPS plans were compared with five LINACs measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINACs, there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one specific LINAC named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINACs’ performance were within the acceptable deviation and delivering radiation dose consistently and accurately.

关键词： Radiotherapy Beam-Matching Linear Accelerator Dosimetry

Improved Analytical Methods for Determination of Residues of Nitrapyrin and 6-Chloropicolinic Acid in Different Crop Matrices by Liquid Chromatography-Tandem Mass Spectrometry

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Agricultural Chemistry and Environment 2024年第3期13卷 263-281页

作者： Fabiola G. Zuno-Floriano Riza L. Reyes-Punongbayan Matt j. Hengel Department of Environmental Toxicology University of California Davis California USA

Novel analytical methods were developed for the determination of nitrapyrin and 6-chloropicolinic acid (6-CPA) residues in agricultural products. Nitrapyrin was extracted with hexane: toluene (1:1, v/v) and 6-CPA with 0.1 N sodium hydroxide (NaOH). For nitrapyrin, samples were cleaned with silica solid phase extraction (SPE) and for 6-CPA with C18 or carbon SPE. Analysis was performed by liquid chromatography-tandem mass spectroscopy (LC-MS/MS) with external calibration (0.010 to 0.0010 µg∙mL−1 for nitrapyrin and 0.0050 to 0.00025 µg∙mL−1 for 6-CPA). Recoveries for nitrapyrin and 6-CPA were 68% - 102% and 66% - 90%, respectively. Nitrapyrin was detected in celery and onion (−1) and 6-CPA in onion, mustard greens and lettuce (−1). Lower level method validation (LLMV) for nitrapyrin and 6-CPA was 0.020 µg∙g−1 and 0.050 µg∙g−1, respectively. The methods presented in this study are robust and were utilized for the registration of nitrapyrin on agricultural commodities in the United States.

关键词： Herbicide Agricultural Products External Calibration LC-MS/MS Registration

Primary and Secondary Microplastic and Nanoplastic Regulations: Perspectives on Water Industry Impacts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Environmental Protection 2024年第6期15卷 697-715页

作者： Shirin Estahbanati Giridhar Upadhyaya Martha j. M. Wells Katherine Y. Bell Brown and Caldwell New York NY USA Brown and Caldwell Irvine CA USA EnviroChem Services Cookeville TN USA Brown and Caldwell Nashville TN USA

Plastic pollution, both primary and secondary, is an environmental challenge, prompting regulatory actions at global and regional levels. With increasing research about the impacts of micro- and nanoplastics on ecosystems and human health, governments worldwide have undertaken efforts to address this issue. The global community has advanced regulatory efforts that have led to the implementation of national laws or regulations in numerous countries. These measures ban or restrict the use of primary and secondary microplastics and nanoplastics. An overview of global and European regulatory frameworks is presented to provide context for the United States (US). In the endeavor to document plastics regulation development in the US, a description of regulatory agencies and their roles in advancing policy and rules as well as future direction and areas for improvement in regulating plastics are introduced. A discussion of what emerging regulations mean to utilities and industries is also provided along with a comparison of regulatory frameworks.

关键词： Microplastic Regulation Environmental Governance Plastic Pollution Mitigation Regulatory Framework

Applications of genetic code expansion technology in eukaryotes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo Yu j.Cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

Analysis of the inflection points of height-diameter models

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2024年第4期11卷 414-422页

作者： Tzeng Yih Lam Mark j.Ducey Department of Forest Resources Management Faculty of ForestryThe University of British Columbia2045-2424 Main MallVancouverBCV6T 1Z4 Canada Department of Natural Resources and the Environment University of New Hampshire114 James HallDurhamNH 03824USA

The inflection point is an important feature of sigmoidal height-diameter(H-D)*** is often cited as one of the properties favoring sigmoidal model ***,there are very few studies analyzing the inflection points of H-D *** goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional *** six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)*** models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial *** distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and *** produced some of the largest inflection *** and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree *** species or decreasing shade tolerance resulted in larger inflection *** trends in the estimated inflection points of HOS and VBR were entirely opposite across the ***,HOS could produce concave H-D curves for portions of the *** on the studied behaviors,the choice between two-parameter models may not *** recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on *** sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with *** study highlights the need to integrate analysis of inflection points into modeling H-D relationships.

关键词： Concavity Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling Points of inflection Species-specific models

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.LEE S.CHANG j.LEE Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring