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Bioactive chiral metabolites from a shark-derived fungus

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Bioactive chiral metabolites from a shark-derived fungus

玻化微珠对秸秆灰/水泥复合材料导热性能的影响

中国化学会第十届全国天然有机化学学术会议

作者： Yi Zhang Jun mu Yan Feng markus Kramer frank Essmann Jin-Yuan Han Hai-Yan Bao Stephanie Grond College of Food Science and technology Guangdong Ocean University School of Environmental and Chemical Engineering Dalian Jiaotong University Institute of Organic Chemistry University of Tübingen marine Science and technology College Zhejiang Ocean University Inter-faculty Institute for Biochemistry University of Tübingen

＜正＞Nine chiral compounds（1-9）were produced by a shark gill-derived fungus Penicillium crustosum AP2t1 in static fermentation,including a new acetylenic compound（1）,a new quinazoline alkaloid（2）,and seven known metabolites[fructigenine A（3）,cyclopenin（4）,cyclopenol（5）,（R）-penipratynolene（6）,（3S,4S）-3,4-dihydro-3,4,8-trihydroxyl-naphthalenone（7）,

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混凝土与水泥制品 2020年第7期 72-76页

作者：王春红鲍鑫支中祥 KO frank ZAKARIA Sarani 左恒峰贾立霞高晓平天津工业大学纺织科学与工程学院 300387 清华大学汽车安全与节能国家重点实验室北京100084 materials Engineering Department University of British ColumbiaVancouverBC V6T 1Z4Canada Bioresources and Biorefinery Laboratory Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia 河北科技大学纺织服装学院石家庄050018 内蒙古工业大学轻工与纺织学院呼和浩特010051

通过响应面Box-Behnken实验设计,对玻化微珠增强秸秆灰/水泥复合材料的性能进行了优化研究。研究结果表明,所选模型具有显著性(P<0.05),模型优化得出的复合材料最优工艺参数为:掺入量为10%,粒径为600μm。在最优工艺下,玻化微珠增强秸秆... 详细信息

通过响应面Box-Behnken实验设计,对玻化微珠增强秸秆灰/水泥复合材料的性能进行了优化研究。研究结果表明,所选模型具有显著性(Pm。在最优工艺下,玻化微珠增强秸秆灰/水泥基复合材料的导热系数为0.2919 W/(m·K),相比未优化处理的,导热系数降低了36%。

关键词：秸秆灰水泥基复合材料玻化微珠响应曲面模型

中元古代具有高的Cr同位素分异特征和高的大气氧浓度

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矿物岩石地球化学通报 2018年第6期37卷 1180-1180页

作者： D.E.Canfield S.C.Zhang A.B.frank X.m.Wang H.J.Wang J.Su Y.t.Ye R.Frei 袁超

大气氧对生命大爆发具有重要意义。然而。前人通过Cr同位素研究表明,中元古代时期具有非常低的大气氧浓度(当今氧水平的0.1%),并不足以使得中元古代真核生物大爆发。Cr同位素是揭示大气氧化历史的一个非常有用的办法。由于Cr^3+物相发... 详细信息

大气氧对生命大爆发具有重要意义。然而。前人通过Cr同位素研究表明,中元古代时期具有非常低的大气氧浓度(当今氧水平的0.1%),并不足以使得中元古代真核生物大爆发。Cr同位素是揭示大气氧化历史的一个非常有用的办法。由于Cr^3+物相发生大陆氧化性风化作用,Cr同位素会发生分馏,重的53Cr同位素会倾向于进入氧化的镉酸盐中(Cr^4+),从而使得残留相(Cr^3+)中亏损重Cr同位素。

关键词： Cr^3+ 中元古代同位素氧浓度大气特征和分异生命大爆发

Volume and fat infiltration of spino-pelvic musculature in adults with spinal deformity

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World Journal of Orthopedics 2015年第9期6卷 727-737页

作者： Bertrand moal Nicolas Bronsard José G Raya Jean marc Vital frank Schwab Wafa Skalli Virginie Lafage Spine Division Hospital for Joint DiseasesNew-York University University Langone Medical Center Nice University Hospital Center Orthopedic and Traumatologic Surgery DepartmentH?pital Saint Roch Center for Biomedical Imaging Department of RadiologyNew York University Langone Medical Center University Hospital of Bordeaux Spinal UnitDepartement of Orthopaedic Surgery Laboratory of Biomechanics Arts et Métiers ParisTech

AIm: to investigate fat infiltration and volume of spino-pelvic muscles in adults spinal deformity(ASD) with magnetic resonance imaging(mRI) and 3D ***: Nineteen female ASD patients(mean age 60 ± 13) were included prospectively and consecutively and had t1-weighted turbo Spin Echo sequence mRIs with Dixon method from the proximal tibia up to t12 vertebra. the Dixon method permitted to evaluate the proportion of fat inside each muscle(fat-water ratio). In order to investigate the accuracy of the Dixon method for estimating fat vs water, the same mRI acquisition was performed on phantoms of four vials composed of different proportion of fat vs water. With muscl'X software, 3D reconstructions of 17 muscles or group of muscles were obtained identifying the muscle's contour on a limited number of axial images [Deformation of parametric specific objects(DPSO) method]. musclar volume(Vmuscle), infiltrated fat volume(Vfat) and percentage of fat infiltration [Pfat, calculated as follow: Pfat = 100 ×(Vfat/Vmuscle)] were characterized by extensor or flexor function respectively for the spine, hip and knee and theirs relationship with demographic data were investigated. RESULtS: Phantom acquisition demonstrated a non linear relation between Dixon fat-water ratio and the real fat-water ratio. In order to correct the Dixon fatwater ratio, the non linear relation was approximated with a polynomial function of degree three using the phantom acquisition. On average, Pfat was 13.3% ± 5.3%. muscles from the spinal extensor group had a Pfat significantly greater than the other muscles groups, and the largest variability(Pfat = 31.9% ± 13.8%, P muscles from the hip extensor group ranked 2nd in terms of Pfat(14% ± 8%), and were significantly greater than those of the knee extensor(P = 0.030). muscles from the knee extensor group demonstrated the least Pfat(12% ± 8%). they were also the only group with a significant correlation between Vmuscle and Pfat(r =-0.

关键词： Spino-pelvic musculature Adults with spinal deformity muscular degeneration muscular volume Fat infiltration Dixon method

聚乙烯基环己烷-聚乙烯-聚乙烯基环己烷三嵌段共聚物溶液的受限结晶研究

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高等学校化学学报 2005年第3期26卷 583-585页

作者：于佩潜李洪胜王震谢续明 Bates frankS. 清华大学化工系高分子研究所北京100084 Department of Chemical Engineering and materials Science University of minnesota MN USA

the crystallization of poly(vinylcyclohexane)-b-poly(ethylene)-b-poly(vinylcyclohexane)(PVCH-PE-PVCH) triblock copolymer/chloroform solution was investigated. the solvent of the solution system was evaporated at various temperatures. It was found that the crystallinity was decreased with increasing the solvent evaporating temperature. this indicated that the crystallinity depends on the crystallization time because the higher the evaporating temperature, the faster the speed of the solvent evaporating is. However, the melting temperature(t_m) of the block copolymer was found to depend on the competition between the crystallization and the microphase separation. When the evaporating temperature is lower(below 333 K), i.e. the speed of the solvent-evaporating is slow, the PE block crystallized freely and the t_m increased with increasing the solvent evaporating temperature, implying that the t_m only depends on the crystalline temperature. On the other hand, with the increasing temperature up to above 343 K for solvent evaporating, two melting peaks at 356 and 377 K were observed for the crystallization of PVCH-PE-PVCH in the solution. It resulted in that the crystallization and the microphase separation of the block copolymer occurred simultaneously. And the confined and unconfined crystallization coexisted for the samples. the competition of the crystallization and the microphase separation can be controlled through changing the solvent evaporating speed.

关键词：聚乙烯基环己烷-聚乙烯-聚乙烯基环己烷微相分离受限结晶

Differential Cross Section measurement for the ~6Li(n,t)~4He Reaction

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中国核科技报告 2002年第S1期 5-7页

作者： ZHANG Guohui tANG Guoyou CHEN Jinxiang SHI Zhaomin Institute of Heavy Ion Physics & mOE Key Laboratory of Heavy Ion Physics, Peking University, Beijing 100871CHEN Zemin Department of Physics, tsinghua University, Beijing 100084Yu.m.Gledenov m. Sedysheva G. Khuukhenkhuu Joint Institute for Nuclear Research, frank Laboratory of Neutron Physics, Dubna 141980, Russia

the differential cross sections and integrated cross sections of the 6Li(n,t)4He reaction were measured at 1.85 and 2.67 meV by using a gridded ionization chamber. Neutrons were produced through the t(p,n)3He reaction. the absolute neutron flux was determined through the 238U(n,f) reaction. Present results are compared with existing data.

关键词： Li Differential Cross Section measurement for the n,t

Estimates of Genetic Variability of <i>mycobacterium tuberculosis</i>Complex and Its Association with Drug Resistance in Cameroon

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Advances in Infectious Diseases 2013年第1期3卷 55-59页

作者： Larissa Kamgue Sidze Emmanuel mouafo tekwu Christopher Kuaban Jean-Paul Assam Assam Jean-Claude tedom Stefan Niemann matthias frank Véronique N. Penlap Beng Institute for tropical medicine University of Tübingen Tübingen Germany Laboratory for tuberculosis Research Biotechnology Centre of Nkolbisson (BTC) University of Yaoundé I Yaoundé Cameroon Pneumology Unit Jamot Hospital Yaoundé Cameroon Research Centre Borstel Molecular Mycobacteriology Borstel Germany

the present study investigates the genetic diversity among mycobacterium tuberculosis complex circulating in the Centre region of Cameroon and analyzes the relationship between genotypes and drug resistance patterns. Spoligotyping was performed by PCR-amplification followed by the reverse hybridization of 298 cultured specimens. Spoligotypes patterns were identified by comparison to reference strains in SPolDB4 database via the mIRU VNtR plus web application. About 97.65% of all tuberculosis (tB) cases were attributed to m. tuberculosis. A total of 65 different profiles were identified. Of these, 40 were represented as Shared types (St) while the others were orphans. LAm10_CAm and Haarlem families were the most prevalent genetic families with 51.01% and 14.09% respectively. St 61, a member of the LAm10_ CAm family formed the largest cluster with 128 (42.95%) isolates. No association was found between genotypes with regard to drug resistance and HIV sero-status. However, there was a significant association between genotypes and age groups. Patients belonging to 15 - 24 and 35 - 44 age groups were more likely infected by LAm10_CAm strains compared to others. the population structure of mycobacterium tuberculosis complex strains from the Centre region was found to be diverse and the spoligotype 61 of the LAm10_CAm family was highly predominant. Isolates of the LAm10_CAm seem to be not associated with drug resistance.

关键词： m. tuberculosis Spoligotyping LAm10_CAm

快中子^64Zn(n，α)^61Ni反应微分截面实验测量

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核技术 2008年第6期31卷 433-437页

作者：张国辉郭利安张家国曹荣太陈金象 Gledenov Yu m Sedysheva m Khuukhenkhuu G 北京大学物理学院核物理与核技术国家重点实验室北京100871 frank Laboratory of Neutron Physics JINR Dubna 141980 Russia Nuclear research Centre National University of Mongolia Ulaanbaatar Mongolia

由于64Zn(n,α)61Ni反应的剩余核是稳定的,不能用通常的活化法来测量,致使该反应截面实验数据缺乏。利用双屏栅电离室作为带电粒子探测器,在En=2.54,4.00,5.03,5.50与5.95meV5个能点,对64Zn(n,α)61Ni反应的微分截面进行了实验测量,并... 详细信息

由于64Zn(n,α)61Ni反应的剩余核是稳定的,不能用通常的活化法来测量,致使该反应截面实验数据缺乏。利用双屏栅电离室作为带电粒子探测器,在En=2.54,4.00,5.03,5.50与5.95meV5个能点,对64Zn(n,α)61Ni反应的微分截面进行了实验测量,并通过微分截面对角度的积分得到了反应截面。实验在北京大学4.5mV静电加速器上进行。2.54meV的单能中子采用固体氚-钛靶t(p,n)3He反应产生,其余四种能量的准单能中子通过氘气体靶D(d,n)3He反应获得。绝对中子通量采用238U(n,f)反应来确定,实验过程中用BF3长中子计数器进行相对中子通量监测。测量结果与已有的实验与评价数据进行了比较。

关键词：快中子 ^64Zn(n,α)^61Ni反应微分截面截面

人类免疫缺陷病毒感染能否防止先兆子痫-子痫的发生

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世界核心医学期刊文摘（妇产科学分册） 2005年第9期1卷 33-34页

作者： frank K.A. Buchmann E.J. Schackis R.C. 张丽娟 P.O. Box 5622 We ltevredenpark 1715 South Africa Prof.

OBJECtIVE: In view of recent suggestions that human immunodeficiency virus ( HI V) infection may protect against preeclampsia, this study was done to evaluate w hether untreated HIV-positive pregnant women have a lower rate of prceclampsia -eclampsia than HIV-negative women. mEtHODS: Subjects for this study were preg nant women from Soweto, South Africa, who gave birth from march to December 2002 at midwife-run clinics or at the Chris Hani Baragwanath Hospital and in whom t he HIV status was known. A sample size calculation indicated that 2,588 subjects would be required to show statistical significance at P th a power of 8 0%for a reduction in the rate of preeclampsia from 8%to 5%with HIV seropositi vity, assuming an HIV seroprevalence rate of 30%. Data collection was by record review from randomly selected patient files and birth registers. RESULtS: In th e total sample of 2,600 women, 1,797 gave birth at the hospital and 803 at the m idwife-run clinics. the HIV seroprevalence rate was 27.1%. Hypertension was fo und in 17.3%of women, with 5.3%having preeclampsia-eclampsia. the rates of pr eeclampsia-eclampsia were 5.2%in HIV-negative and 5.7%in HIV-positive women (P = .61). CD4 count results were available for only 13 women (0.5%). CONCLUSI ON: Human immunodeficiency virus seropositivity was not associated with any redu ction in the risk of developing preeclampsia-eclampsia.

关键词：血清阳性率出生登记计数结果样本量病历记录