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Asymmetric catalytic anhydride openings via carbon-based nucleophiles

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chinese chemical Letters 2014年第1期25卷 1-8页

作者： chen Zheng Fen-er chen Department of chemistry Fudan University

The asymmetric desymmetrization of cyclic anhydrides via the addition of carbon-based nucleophiles has been the focus of considerable levels of interest because it leads to optically active products. Over the past 20 years, a variety of different catalytic asymmetric alkylation reactions have been developed for the desymmetrization of cyclic anhydrides using different metal reagents as nucleophiles and using chiral ligands. The purpose of this review is to provide an overview of significant developments in this field. ~ 2013 Fen-er chen. Published by Elsevier B.V. on behalf of chinese chemical Society. All rights reserved.

关键词： cyclic anhydrides carbon-based nucleophiles chiral ligands Asymmetric catalysis Metal reagents

characteristics of American scholars’research on chinese Medical classics and Their contributions

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chinese Journal of Integrative Medicine 2020年第8期26卷 629-632页

作者： WANg er-liang cHEN Xiao school of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China

chinese medical classics are important carriers for the inheritance,innovation and development of academic thoughts of chinese medicine(cM),containing rich thoughts on diagnosis and treatment as well as therapeutic principles of *** international exchange of cM has a very long *** the development of society,Western scholars in modern times are deepening their researches on chinese medical *** would provide a new way for promoting cM in Western countries to investigate researches made by famed American scholars and their academic viewpoints.

关键词： chinese medicine classics international exchange American scholar

Effect of Laser Welding on Properties of Dissimilar Joint of Al-Mg-Si and Al-Mn Aluminum Alloys

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Journal of Materials science & Technology 2010年第3期26卷 276-282页

作者： c.c.chang c.P.chou S.N.Hsu g.Y.Hsiung J.r.chen Department of Mechanical Engineering National Chiao-Tung University National Synchrotron radiation research center Department of Biomedical Engineering and Environmental sciences National Tsing-Hua University

This study discusses the welding properties for the components of an aluminum-alloy ultra-high vacuum chamber and beam position monitor （BPM）.The welding parameters include the modes of laser output （pulsed wave and continuous wave）,welding speed,shield gas flow,welding bead structure,and focusing *** results showed that the welding defect rate of the pulsed wave type was larger than that of the continuous wave *** crack in the welding bead reduced with decreasing welding *** fusion penetration of the welding bead was higher when the focusing distance was long enough to deepen into the welding *** morphology during the experimental process revealed the proper flow of shield *** adaptability design of the welding bead structure in the preceding processes had more effect on overall welding structure and morphology.

关键词： Laser welding Aluminum alloy Ultra-high vacuum Beam position monitor (BPM)

Preparation Process and Mechanical Properties of PLA/PcL Intravascular Stent

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Journal of Donghua University(English Edition) 2014年第5期31卷 640-642页

作者： WANg cong-er Key Laboratory of Textile science & Technology Ministry of Education Donghua University Shanghai 201620 China college of Textiles Donghua University Shanghai 201620 China

A hand-made biodegradable intravascular stent with zig- zag structure has been developed, which made from polylactic acid （ PLA ） braided thread and poly-eaprolactone （ PcL ） tube. This paper showed the preparation process of the PLA braded thread and stent, and discussed the heat setting process of the stents. The sixteen groups of stents were made for the heat setting experiments, discussing two factors on four levels. radial compression behavior of stents was tested by plate compression method. The result showed that both the heat setting temperature and time had significant effects on stent compression strength. The compression recovery rate was mainly affected by heat setting temperature. The optimized heat setting condition should be 90-100℃ for 45 rain.

关键词： biodegradable intravascular stents polylactic acid(PLA) heat setting process compression properties

risk factors for long cOVID in children and adolescents:a systematic review and meta-analysis

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World Journal of Pediatrics 2024年第2期20卷 133-142页

作者： Daniel g.rayner Elaine Wang cloris Su om D.Patel Stephanie Aleluya Alessandra giglia Evelyn Zhu Maha Siddique Department of Health research Methods Evidenceand ImpactFaculty of Health SciencesMcMaster University1280 Main St WHamiltonONL8S 4K1Canada Faculty of Health sciences McMaster University1280 Main St WHamiltonON L8S 4K1Canada Faculty of science McMaster University1280 Main St WHamiltonONL8S 4K1Canada

Background The long-term sequelae of cOVID-19 in children and adolescents remain poorly understood and *** systematic review and meta-analysis sought to summarize the risk factors for long cOVID in the pediatric *** We searched six databases from January 2020 to May 2023 for observational studies reporting on risk factors for long cOVID or persistent symptoms those were present 12 or more weeks post-infection using multivariable regression *** registries,reference lists of included studies,and preprint servers were hand-searched for relevant ***-effects meta-analyses were conducted to pool odds ratios for each risk *** study risk of bias was rated using QUIPS,and the grADE framework was used to assess the certainty of evidence for each unique *** Sixteen observational studies(N=46,262)were included,and 19 risk factors were amenable to *** moderate certainty in the evidence,age(per 2-year increase),allergic rhinitis,obesity,previous respiratory diseases,hospitalization,severe acute cOVID-19,and symptomatic acute cOVID-19 are probably associated with an increased risk of long *** sex,asthma,comorbidity,and heart diseases may be associated with an increased risk of long cOVID,and Asian and Black races may be associated with a decreased risk of long *** did not observe any credible subgroup effects for any risk *** The current body of literature presents several compelling risk factors for the development of long cOVID in the pediatric *** research is necessary to elucidate the pathophysiology of long cOVID.

关键词： cOVID-19 Long cOVID Post-acute cOVID-19 syndrome Pediatrics risk factors

Sex-dependent increase of movement activity in the freshwater isopod Asellus aquaticus following adaptation to a predator-free cave habitat

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current Zoology 2023年第4期69卷 418-425页

作者： ELTE Eötvös Loránd University Hajriz Berisha gergely Horváth Žiga Fišer gergely Balázs cene Fišer gábor Herczeg Author Notes Behavioural Ecology group Department of Systematic Zoology and EcologyBiological InstituteELTE Eötvös Loránd UniversityPázmány Péter sétány 1/CBudapestHungary H-1117 ELKH-ELTE-MTM Integrative Ecology research group Pázmány Péter sétány 1/CBudapestHungary H-1117 Department of Biology Biotechnical FacultyUniversity of LjubljanaJamnikarjeva 1011000 LjubljanaSlovenia

Populations experiencing negligible predation pressure are expected to evolve higher behavioral ***,when sexes have different expected benefits from high activity,the adaptive shift is expected to be ***,we compared movement activity of one cave(lack of predation)and three adjacent surface(high and diverse predation)populations of Asellus aquaticus,a freshwater isopod known for its independent colonization of several caves across *** predicted 1)higher activity in cave than in surface populations,with 2)the difference being more pronounced in males as they are known for active mate searching behavior,while females are *** was assessed both in the presence and absence of *** results supported both predictions:movement activity was higher in the cave than in the surface populations,particularly in *** predation pressure in the cave-adapted population is most likely the main selective factor behind increased behavioral activity,but we also showed that the extent of increase is sex-specific.

关键词： adaptation cave colonization movement activity predator-free environment

Meiofaunal community Spatial Distribution and Diversity as Indicators of Ecological Quality in the Bohai Sea, china

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Journal of Ocean University of china 2021年第2期20卷 409-420页

作者： cUI chunyan ZHANg Zhinan HUA er college of Marine Life sciences Ocean University of ChinaQingdao 266100China

The Bohai Sea is a semi-enclosed marginal sea in the North West Pacific. Meiofauna samples were collected from 22 stations in the Bohai Sea to document the spatial distribution, structure, and diversity of the meiofaunal community and investigate the major factors influencing the community features. A total of 20 higher taxa of meiofauna were identified. The dominant group was Nematoda, accounting for 90.8% of the total meiofaunal abundance on average, followed by copepoda, Bivalvia, Polychaeta, Kinorhyncha, and Ostracoda. Meiofaunal abundance ranged from 121 ± 89 ind(10 cm2)-1 to 3042 ± 1054 ind(10 cm2)-1. Diversity indices also varied among different stations, with a Margalef's richness index(d) of 1.1–3.1, Shannon-Wiener diversity index(H′) of 0.7–1.8, and Pielou's evenness index(J′) of 0.4– 0.8. Meiofaunal abundance and diversity indices were significantly lower in the areas of Bohai Bay and adjacent to Laizhou Bay. The correlation analysis showed that meiofaunal abundance and diversity indices are closely linked to variations in sediment silt-clay content, medium grain size(MDΦ), and chlorophyll-a concentrations. The ecological quality status of most stations can be ranked from poor to moderate based on meiofaunal richness. According to the value of nematode to copepod ratio(Ne:co ratio), most stations are uncontaminated, except seven stations are slightly or moderately contaminated. Both meiofaunal richness and Ne:co ratio indicate the poor ecological quality of three stations adjacent to Laizhou Bay. The efficiency of the meiofauna communities as environmental indicators will be tested in a greater area in the future studies.

关键词： meiofauna spatial distribution biodiversity ecological quality the Bohai Sea

Influence of earthquake direction on the seismic response of irregular plan rc frame buildings

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 243-256页

作者： Magliulo g Maddaloni g Petrone c University of Naples Federico II Department of Structures for Engineering and Architecture University of Naples Parthenope Department of Engineering

The nonlinear response of structures is usually evaluated by considering two accelerograms acting simultaneously along the orthogonal directions. In this study, the infl uence of the earthquake direction on the seismic response of building structures is examined. Three multi-story rc buildings, representing a very common structural typology in Italy, are used as case studies for the evaluation. They are, respectively, a rectangular plan shape, an L plan shape and a rectangular plan shape with courtyard buildings. Nonlinear static and dynamic analyses are performed by considering different seismic levels, characterized by peak ground acceleration on stiff soil equal to 0.35 g, 0.25 g and 0.15 g. Nonlinear dynamic analyses are carried out by considering twelve different earthquake directions, and rotating the direction of both the orthogonal components by 30° for each analysis(from 0° to 330°). The survey is carried out on the L plan shape structure. The results show that the angle of the seismic input motion signifi cantly infl uences the response of rc structures; the critical seismic angle, i.e., the incidence angle that produces the maximum demand, provides an increase of up to 37% in terms of both roof displacements and plastic hinge rotations.

关键词： plan irregularity nonlinear analyses reinforced concrete buildings seismic performance ground motion directionality

Anti- MSP-1_(19) antibody (Igg) and reactive oxygen species (rOS) response against malaria infection in pregnancy in South Western Nigeria

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Asian Pacific Journal of Tropical Medicine 2009年第2期2卷 9-15页

作者： Akanbi om Odaibo AB Ademowo Og Department of Environmental Biology and Fisheries Faculty of scienceAdekunle Ajasin UniversityAkungba-AkokoOndo StateNigeria Department of Zoology Parasitology UnitUniversity of IbadanIbadanNigeria Institute for Advanced Medical research and Training College of MedicineUniversity of IbadanIbadanNigeria

Objective:Although immunity to malaria is reduced in pregnancy,the maternal immune system still continues to respond to malaria infection by the production of *** has been reported to play significant role in immune response against ***-MSP-1_(19) antibody and reactive oxygen species have been shown to be protective against malaria infection in *** work assessed the response of anti-MSP-1_(19) antibody(a promising blood stage vaccine candidate antigen) and oxidative stress in 250 pregnant ***: Blood samples were collected in dry and wet *** falciparum infection was determined by microscopy, anti-MSP-1_(19) Igg level was investigated using ***(MDA) and reduced glutathione (gSH) were used as indicators of oxidative stress and they were quantified ***: Parasitaemia was significantly higher(Pry season and its level decreased with *** was a significant increase(Pgg and MDA levels in the dry than wet ***-MSP-1_(19) Igg and MDA levels were significantly higher in *** positive primigravidae than *** negative primigravidae in both wet and dry *** wet season anti-MSP-1_(19) Igg level was significantly increased(Pgravidae than *** negative. The anti-MSP-1_(19) Igg and MDA were significant higher in *** positive multigravidae than primigravidae. reduced glutathione(gSH) level was significantly reduced(Pg malaria positive than malaria negative patients in both ***:This study suggests that Igg and MDA response were positively associated with the presence of malaria infection.

关键词： Pregnancy Malaria reactive oxygen species Anti-MSP-l_(19) antibody(Igg) MDA