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Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang Yang Liang Julius Rebek jr. Yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,o-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Reflections on four decades of physical activity epidemiology

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Journal of Sport and Health Science 2024年第5期13卷 608-610页

作者： Barbara Sternfeld David R.Jacobs jr. Division of Research Kaiser Permanente Northern CaliforniaOaklandCA 94610USA Division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

In 1985,Public Health Reports published a series of papers prepared for a workshop sponsored by the Centers for Disease Control and Prevention(CDC).1 Building on the seminal work of Jeremy Morris and Ralph Paffenbarger jr.,who were among the first to use epidemiological methods to study physical activity(PA),2,3 the workshop itself was the result of a growing scientific understanding of the importance of“physical fitness and exercise for improving the health of the public”.

关键词： semi workshop Ralph

Climate bonds toward achieving net zero emissions and carbon neutrality:Evidence from machine learning technique

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Journal of Management Science and Engineering 2024年第1期9卷 1-15页

作者： Hermas Abudu Presley K.Wesseh jr. Boqiang Lin College of overseas Education Chengdu UniversityChengdu610106SichuanChina School of Management China Institute for Studies in Energy PolicyCollaborative Innovation Center for Energy Economics and Energy PolicyXiamen UniversityFujian361005China Center for African Development Strategy(CFADS) MonroviaLiberia

The Conference of the Parties(CoP26 and 27)placed significant emphasis on climate financing policies with the objective of achieving net zero emissions and carbon ***,studies on the implementation of this policy proposition are *** address this gap in the literature,this study employs machine learning techniques,specifically natural language processing(NLP),to examine 77 climate bond(CB)policies from 32 countries within the context of climate *** findings indicate that“sustainability”and“carbon emissions control”are the most outlined policy objectives in these CB ***,the study highlights that most CB funds are invested toward energy projects(i.e.,renewable,clean,and efficient initiatives).However,there has been a notable shift in the allocation of CB funds from climate-friendly energy projects to the construction sector between 2015 and *** shift raises concerns about the potential redirection of funds from climate-focused investments to the real estate industry,potentially leading to the greenwashing of climate ***,policy sentiment analysis revealed that a minority of policies hold skeptical views on climate change,which may negatively influence climate ***,the findings highlight that the effective implementation of CB policies depends on policy goals,objectives,and ***,this study contributes to the literature by employing NLP techniques to understand policy sentiments in climate financing.

关键词： Climate bonds funds utilization Climate bonds policy text mining Machine learning technique Net zero emissions Policy sentiment analysis

SnRK1a1, a new player in the sucrose-opaque2 network during endosperm filling

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Molecular Plant 2024年第8期17卷 1172-1174页

作者： Kelly Mayrink Balmant Marcio F.R.Resende jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(Flint-Garcia et al.,2009).

关键词： endosperm reservoir Flint

Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1322-1332页

作者： Qinghe Cui Xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik jr. Dzmitry Bahrets Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the *** technology has a very broad application prospect in industrial *** have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this *** this review,metals were classified according to their crystal *** effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were *** main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism

Capacitorless Solid-state Power Filter for Single-phase DC-AC Converters

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CES Transactions on Electrical Machines and Systems 2024年第3期 367-377页

作者： Haitham Kanakri Euzeli C. Dos Santos, jr. IEEE Purdue University Electrical and Computer Engineering Department

Converters rely on passive filtering as a crucial element due to the high-frequency operational characteristics of power electronics. Traditional filtering methods involve a dual inductor-capacitor(LC) cell or an inductor-capacitor-inductor(LCL) T-circuit. However, capacitors are susceptible to wear-out mechanisms and failure modes. Nevertheless, the necessity for monitoring and regular replacement adds to an elevated cost of ownership for such systems. The utilization of an active output power filter can be used to diminish the dimensions of the LC filter and the electrolytic dc-link capacitor, even though the inclusion of capacitors remains an indispensable part of the system. This paper introduces capacitorless solid-state power filter(SSPF) for single-phase dc-ac converters. The proposed configuration is capable of generating a sinusoidal ac voltage without relying on capacitors. The proposed filter, composed of a planar transformer and an H-bridge converter operating at high frequency, injects voltage harmonics to attain a sinusoidal output voltage. The design parameters of the planar transformer are incorporated, and the impact of magnetizing and leakage inductances on the operation of the SSPF is illustrated. Theoretical analysis, supported by simulation and experimental results, are provided for a design example for a single-phase system. The total harmonic distortion observed in the output voltage is well below the IEEE 519 standard. The system operation is experimentally tested under both steady-state and dynamic conditions. A comparison with existing technology is presented, demonstrating that the proposed topology reduces the passive components used for filtering.

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Many Kinds of Reserved Judgement in No-Data Problem

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Applied Mathematics 2024年第1期15卷 1-8页

作者： Houju Hori jr. Nara Community Tsubakikishi Shrine Nara Japan

The reserved judgment can be broadly categorized into three types: Re-Do, Re-Set, and Natural Flowing Case (i.e. step by step in Re-Try). Hori et al. constructed the Bayes-Fuzzy Estimation and demonstrated that system theory can be applied to the possibility of Markov processes, and that decision-making approaches can be applied to sequential Bayes estimation. In this paper, we focus on the Natural Flowing Case within reserved judgment. Here, the possibility of oblique (or principal) factor rotation is considered as a part of the tandem fuzzy system that follows step by step for sequential Bayes estimation. Ultimately, we achieve a significant result whereby the expected utility can be calculated automatically without the need to construct a utility function for reserved judgment. There, this utility in Re-Do can be calculated by the prior utility, and that utility in Re-set does not exist by our research in this paper. Finally, we elucidate the relationship between fuzzy system theory and fuzzy decision theory through an applied example of Bayes-Fuzzy theory. Fuzzy estimation can be applied to only normal making decision, but it is impossible to apply abnormal decision problem. our Vague, specially Type 2 Vague can be applied to abnormal case, too.

关键词： Bayes-Fuzzy Estimation Re-Do Re-Set Indifferent Zone Reserved Judgement

2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities

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Journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrmann Erik A.Willis Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs jr. Kansas Center for Metabolism and obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Department Syracuse UniversitySyracuseNY 13244USA Clinical Sciences Division Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA College of Health and Human Services University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across *** original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 *** a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since *** replaced estimated METs with measured values when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 *** added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older *** added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major ***:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health *** new website with the complete lists of PAs and supporting resources is available at https://***.

关键词： Adults Energy expenditure Exercise MET Physical Activities

Between Quantum Mechanics and General Relativity

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Journal of Modern Physics 2024年第8期15卷 1199-1228页

作者： Walter James Christensen jr. Department of Physics and Astronomy Cal Poly Pomona University Pomona USA

The origin of elementary particle mass is considered as a function of n-valued graviton quanta. To develop this concept we begin in a cold region of “empty space” comprised of only microscopic gravitons oscillating at angular frequency ω. From opposite directions enters a pair of stray protons. Upon colliding, heat and energy are released. Customarily, this phase and what follows afterward would be described by Quantum Chromodynamics (QCD). Instead, we argue for an intermediary step. one in which neighboring gravitons absorb discrete amounts of plane-wave energy. Captured by the graviton, the planewave becomes a standing wave, whereupon its electromagnetic energy densities are converted into gravitational quanta. Immediately thereafter an elementary particle is formed and emitted, having both mass and spin. From absorption to conversion to emission occurs in less than 3.7 × 10−16 s. During this basic unit of hybrid time, general relativity and quantum physics unite into a common set of physical laws. As additional stray protons collide the process continues. over eons, vast regions of spacetime become populated with low-mass particles. These we recognize to be dark matter by its effects on large scale structures in the universe. Its counterpart, dark energy, arises when the conversion of gravitational quanta to particle emission is interrupted. This causes the gravitational quanta to be ejected. It is recognized by its large scale effects on the universe.

关键词： Dark Matter and Energy Gravitational Quanta Graviton Standing Wave Schwarzschild Metric General Relativity Quantum Physics Unified Field Theory Blackholes