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Chinese j.urnal of Structural Chemistry 2007年第5期26卷 594-598页

作者： HUANG Wei YUAN Cai Ansaldi Mireille Morelli Xavier Edward j. Meehan CHEN Li-Qing HUANG Ming-Dong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beo＇ing 100039 China Laboratoire de Chimie Bacte＇rienne Institut de Biologie Structurale et Microbiologie CentreNational de la Recherche Scientifique 31 Chemin Joseph Aiguier 13402 Marseille Cedex 20 France Laboratoire de Chimie Bactoéienne CNRS/IBSM BIP Laboratory 31 Chemin Joseph Aiguier 13402 Marseille Cedex 20 France Laboratory for Structural Biology Department of Chemistry Graduate Programs of Biotechnology Chemistry and Materials Science University of Alabama in Huntsville Huntsville AL 35899 USA

TorI, a Tor system inhibitor acting through protein-protein interaction with the TorR response regulator, is an excisionase that interacts with the integrase and DNA during prophage excision. It has been crystallized by the vapor-diffusion method using polyethylene glycol 3350 as a precipitant at pH 8.5. The X-ray diffraction data sets from the TorI crystal was collected at a resolution of 2.1 , using a synchrotron source. The crystal belongs to primitive monoclinic lattice with cell parameters of 46.210 × 53.992 × 73.561A

关键词： Torl inhibitor crystallization X-ray diffraction

Effects of metoclopramide on gastric motility measured by short-term bio-impedance

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World j.urnal of Gastroenterology 2009年第38期15卷 4763-4769页

作者： María-Raquel Huerta-franco Miguel Vargas-Luna Kathleen M Capaccione Etna Yaez-Roldán Ulises Hernández-Ledezma Ismael Morales-Mata Teodoro Córdova-Fraga Department of Applied Science and Labor Research DCS-Campus LeónUniversity of Guanajuato Department of Physical Engineering DCI-Campus LeónUniversity of Guanajuato Robert Wood j.hnson Medical School The University of Medicine and Dentistry of New Jersey

AIM:To analyze the accuracy of short-term bio-impedance as a means of measuring gastric ***: We evaluated differences in the short-term electrical bio-impedance signal from the gastric region in the following conditions: (1) fasting state, (2) after the administration of metoclopramide (a drug that induces an increase in gastric motility) and (3) after food ingestion in 23 healthy volunteers. We record-ed the real component of the electrical impedance signal from the gastric region for 1000 s. We performed a Fast Fourier Transform (FFT) on this data and then compared the signal among the fasting, medicated, and postprandial conditions using the median of the area under the curve, the relative area under the curve and the main peak ***: The median of the area under the curve of the frequency range in the region between 2-8 cycles per minute (cpm) decreased from 4.7 cpm in the fasting condition to 4.0 cpm in the medicated state (t=3.32, P=0.004). This concurred with the decrease seen in the relative area under the FFT curve in the region from 4 to 8 cpm from 38.3% to 26.6% (t=2.81, P=0.012) and the increase in area in the region from 2 to 4 cpm from 22.4% to 27.7%, respectively (t=-2.5, P=0.022). Finally the main peak position also decreased in the region from 2 to 8 cpm. Main peak activity in the fasting state was 4.72 cpm and declined to 3.45 cpm in the medicated state (t=2.47, P=0.025). There was a decrease from the fasting state to the postprandial state at 3.02 cpm (t=4.0, P=0.0013). CONCLUSION: Short-term electrical bio-impedance can assess gastric motility changes in individuals experiencing gastric stress by analyzing the area medians and relative areas under the FFT curve.

关键词： Bio-impedance Fast Fourier Transform Gastric motility Metoclopramide Postprandial

重稀土HRENiGa_(2)(HRE=Dy,Ho或Er)化合物的优异低温磁热性能

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Science China Materials 2023年第1期66卷 249-256页

作者：郭丹 Luis M.Moreno-Ramírez j.a-Yan Law 张义坤 Victorino franco Key Laboratory of Novel Materials for Sensor of Zhej.ang Province&School of Electronics and Information Engineering Hangzhou Dianzi UniversityHangzhou 310012China Departamento de Física de la Materia Condensada ICMS-CSICUniversidad de SevillaP.O.Box 1065.41080-SevillaSpain State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200072China

RENiX_(2)化合物(其中RE为稀土元素,X为p区元素)在低温磁制冷应用中受到高度关注.它们根据元素的不同可以结晶成CeNiSi_(2)型、NdNiGa_(2)型或MgCuAl_(2)型晶体结构,并表现出不同类型的磁有序性从而影响其磁性.MgCuAl_(2)型铝化物由于... 详细信息

RENiX_(2)化合物(其中RE为稀土元素,X为p区元素)在低温磁制冷应用中受到高度关注.它们根据元素的不同可以结晶成CeNiSi_(2)型、NdNiGa_(2)型或MgCuAl_(2)型晶体结构,并表现出不同类型的磁有序性从而影响其磁性.MgCuAl_(2)型铝化物由于具有有利的铁磁基态从而表现出比CeNiSi_(2)型硅化物和NdNiGa_(2)型镓化物更大的磁热性能.此外,RENiGa_(2)镓化物根据RE元素的不同可以结晶成NdNiGa_(2)或MgCu Al_(2)型结构.本文中,我们选择重稀土(HRE)元素来探索HRENiGa_(2)(HRE=Dy,Ho或Er)镓化物的微观结构、磁有序和磁热性能.三种化合物均以MgCuAl_(2)型晶体结构结晶,并且随着温度的升高经历了从铁磁到顺磁的二级磁相转变.DyNiGa_(2),HoNiGa_(2)和ErNiGa_(2)化合物的最大等温磁熵变(|ΔSisomax|)值分别为6.2,10.4和11.4 j.kg^(-1)K^(-1)(0-5T),这与许多最近报道的低温磁制冷材料性能相当.特别地,HoNiGa_(2)和ErNiGa_(2)化合物(包括它们的复合材料)在氢气液化的温度范围内表现出优异的磁热性能.

关键词：重稀土磁热性能晶体结构磁制冷材料稀土元素磁有序等温磁熵变硅化物

Engineered neuronal microtissue provides exogenous axons for delayed nerve fusion and rapid neuromuscular recovery in rats

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Bioactive Materials 2022年第12期7卷 339-353页

作者： j.stin C.Burrell Suradip Das franco A.Laimo Kritika S.Katiyar Kevin D.Browne Robert B.Shultz Vishal j.Tien Phuong T.Vu Dmitriy Petrov Zarina SAli j.seph M.Rosen D.Kacy Cullen Center for Brain Inj.ry&Repair Department of NeurosurgeryPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Bioengineering School of Engineering&Applied ScienceUniversity of PennsylvaniaPhiladelphiaPAUSA Center for Neurotrauma Neurodegeneration&RestorationCorporal Michael J.Crescenz Veterans Affairs Medical CenterPhiladelphiaPA19104USA Axonova Medical LLCPhiladelphiaPAUSA Dartmouth-Hitchcock Medical Center Division of Plastic SurgeryDartmouth CollegeLebanonNHUSA

Nerve inj.ry requiring surgical repair often results in poor functional recovery due to the inability of host axons to re-grow long distances and reform meaningful connections with the target muscle. While surgeons can re-route local axon fascicles to the target muscle, there are no technologies to provide an exogenous source of axons without sacrificing healthy nerves. Accordingly, we have developed tissue engineered neuromuscular interfaces (TE-NMIs) as the first inj.ctable microtissue containing motor and sensory neurons in an anatomically-inspired architecture. TE-NMIs provide axon tracts that are intended to integrate with denervated distal structures and preserve regenerative capacity during prolonged periods without host innervation. Following implant, we found that TE-NMI axons promoted Schwann cell maintenance, integrated with distal muscle, and preserved an evoked muscle response out to 20-weeks post nerve transection in absence of innervation from host axons. By repopulating the distal sheath with exogenous axons, TE-NMIs also enabled putative delayed fusion with proximal host axons, a phenomenon previously not achievable in delayed repair scenarios due to distal axon degeneration. Here, we found immediate electrophysiological recovery after fusion with proximal host axons and improved axon maturation and muscle reinnervation at 24-weeks post-transection (4-weeks following delayed nerve fusion). These findings show that TE-NMIs provide the potential to improve functional recovery following delayed nerve repair.

关键词： Nerve regeneration Neuromuscular inj.ry Muscle preservation Tissue engineering Microtissue Axon fusion

Nonlinear orbital uncertainty propagation with differential algebra and Gaussian mixture model

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Science China(Physics,Mechanics & Astronomy) 2019年第3期62卷 82-92页

作者： Zhen-j.ang Sun Ya-Zhong Luo Pierluigi di Lizia franco Bernelli Zazzera College of Aerospace Science and Engineering National University of Defense Technology Department of Aerospace Science and Technology Politecnico di Milano

Nonlinear uncertainty propagation is of critical importance in many application fields of astrodynamics. In this article, a framework combining the differential algebra technique and the Gaussian mixture model method is presented to accurately propagate the state uncertainty of a nonlinear system. A high-order Taylor expansion of the final state with respect to the initial deviations is firstly computed with the differential algebra technique. Then the initial uncertainty is split to a Gaussian mixture *** the high-order state transition polynomial, each Gaussian mixture element is propagated to the final time, forming the final Gaussian mixture model. Through this framework, the final Gaussian mixture model can include the effects of high-order terms during propagation and capture the non-Gaussianity of the uncertainty, which enables a precise propagation of probability density. Moreover, the manual derivation and integration of the high-order variational equations is avoided, which makes the method versatile. The method can handle both the application of nonlinear analytical maps on any domain of interest and the propagation of initial uncertainties through the numerical integration of ordinary differential equation. The performance of the resulting tool is assessed on some typical orbital dynamic models, including the analytical Keplerian motion, the numerical j.2 perturbed motion,and a nonlinear relative motion.

关键词： nonlinear orbit uncertainty propagation differential algebra Gaussian mixture model taylor expansion

No benefits from warming even for subnival vegetation in the central Himalayas

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Science Bulletin 2021年第18期66卷 1825-1829,M0003页

作者： Shalik Ram Sigdel j.yram Pandey Eryuan Liang Sher Muhammad Flurin Babst Steven W.Leavitt Miaogen Shen Haifeng Zhu franco Salerno Shilong Piao j.j.lio Camarero j.sep Penuelas State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China International Centre for Integrated Mountain Development(ICIMOD) KathmanduNepal Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China School of Natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Laboratory of Tree-Ring Research University of ArizonaAZ 85721USA Water Research Institute-National Research Council(IRSA-CNR) Brugherio 20861Italy Instituto Pirenaico de Ecología(IPE-CSIC) Zaragoza 50080Spain CSIC Global Ecology Unit CREAF-CSIC-UABCerdanyola del VallesCatalonia 08913Spain CREAF Cerdanyola del VallesCatalonia 08913Spain

普遍认为变暖有利于高山植被生态系统,并已经导致冰缘植物向高海拔的扩张.珠峰山谷金字塔气象站(海拔5050 m)1994~2018的气象记录显示,高海拔山区呈显著的暖干化趋势.然而,我们依然不清楚暖干化是否对冰缘植被更新和分布造成显著影响?... 详细信息

普遍认为变暖有利于高山植被生态系统,并已经导致冰缘植物向高海拔的扩张.珠峰山谷金字塔气象站(海拔5050 m)1994~2018的气象记录显示,高海拔山区呈显著的暖干化趋势.然而,我们依然不清楚暖干化是否对冰缘植被更新和分布造成显著影响?本研究在喜马拉雅山中段3个山谷建立了8块(30 m×120 m)滇藏方枝柏(j.niperus indica)和高山柏(j.niperus squamata)灌木线样地(海拔介于4344~5074 m之间).样地调查揭示,自20世纪90年代之前所有样地种群更新呈增加的趋势,然而90年代以来更新持续下降.种群更新与春季、夏季温度之间呈现显著的负相关关系,暗示了暖干化加剧了水分胁迫,并限制了种群的更新.另外,近60年来所有灌木线位置稳定.近30年遥感数据也证实,研究区冰缘植被无变绿趋势,甚至出现2%-6%的植被生长减弱现象.因此,进一步研究应该探讨冰缘植被生长减弱对喜马拉雅山区水循环和生物多样性的影响.

关键词：生物多样性喜马拉雅山区高海拔山区种群更新植被生态系统植被生长气象记录

Investigation of the transcriptomic and metabolic changes associated with superficial scald physiology impaired by lovastatin and 1-methylcyclopropene in pear fruit(cv.“Blanquilla”)

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Horticulture Research 2020年第1期7卷 2229-2245页

作者： j.rdi Giné-Bordonaba Nicola Busatto Christian Larrigaudière Violeta Lindo-García Gemma Echeverria Urska Vrhovsek Brian Farneti franco Biasioli Concetta De Quattro Marzia Rossato Massimo Delledonne Fabrizio Costa XaRTA-Postharvest Institute for Food and Agricultural Research and Technology(IRTA)Edifici FruitcentreParc Científic i Tecnològic Agroalimentari de Lleida25003 LleidaSpain Department of Genomics and Biology of Fruit Crops Research and Innovation CentreFondazione Edmund Machvia Mach 138010 San Michele all’AdigeTrentoItaly Department of Food Quality and Nutrition Research and Innovation CentreFondazione Edmund Machvia Mach 138010 San Michele all’AdigeTrentoItaly Department of Biotechnology University of VeronaStrada le Grazie 1537134 VeronaItaly Center Agriculture Food Environment University of Trentovia Mach 138010 San Michele all’AdigeTrentoItaly

To elucidate the physiology underlying the development of superficial scald in pears,susceptible“Blanquilla”fruit was treated with different compounds that either promoted(ethylene)or repressed(1-methylcyclopropene and lovastatin)the incidence of this disorder after 4 months of cold *** data show that scald was negligible for the fruit treated with 1-methylcyclopropene or lovastatin,but highly manifested in untreated(78%incidence)or ethylenetreated fruit(97%incidence).The comparison between the fruit metabolomic profile and transcriptome evidenced a distinct reprogramming associated with each *** all treated samples,cold storage led to an activation of a cold-acclimation-resistance mechanism,including the biosynthesis of very-long-chain fatty acids,which was especially evident in 1-methylcyclopropane-treated *** the treatments applied,only 1-methylcyclopropene inhibited ethylene production,hence supporting the involvement of this hormone in the development of ***,a common repression effect on the PPO gene combined with higher sorbitol content was found for both lovastatin and 1-methylcyclopropene-treated samples,suggesting also a non-ethylene-mediated process preventing the development of this *** results presented in this work represent a step forward to better understand the physiological mechanisms governing the etiology of superficial scald in pears.

关键词： superficial impaired hence

Low-temperature magnetic properties of horse spleen ferritin

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Chinese Science Bulletin 2010年第27期55卷 3174-3180页

作者： TIAN LanXiang 1,2,CAO ChangQian 1,2,LIU QingSong 1,2 &PAN YongXin 1,2 1Key Laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beij.ng 100029,China 2franco-Chinese Biomineralization and Nano-structures Laboratory,Beij.ng 100029,China Key Laboratory of the Earth''s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China franco-Chinese Biomineralization and Nano-structures Laboratory Beijing 100029 China

The magnetic properties of the antiferromagnetic cores in ferritin are of importance in the construction and improvement of ferritin-based magnetic resonance imaging systems and their application to environmental *** this study,we carry out integrated magnetic and transmission electron microscopy analyses of horse spleen ferritin(HoSF)to understand the relationships between the magnetic behavior of HoSF and temperature,applied field and grain-size *** R-value from the Wohlfarth-Cisowski test for the investigated sample at 5 K was 0.46,indicating very weak magnetostatic interactions among the nanoparticles of *** nanoparticles of HoSF show superparamagnetic properties at room temperature,while below the blocking temperature of Tb≈12 K it has a net magnetic moment that comes from the uncompensated spins of the nanoparticle surface or *** thermal relaxation process of HoSF follows the Néel-Arrhenius *** low-temperature AC susceptibility data,we calculated the effective magnetic anisotropy energy Ea=(5.52±0.16)×10-21 j.the effective magnetic anisotropy energy constant Keff=(4.65±0.14)×10 4 j.m3 and the pre-exponential frequency factor f0 =(4.52±2.93)×1011 *** values are useful in understanding the magnetic behavior of the antiferromagnetic nanoparticles and their potential application in biomedical technology.

关键词：马脾铁蛋白低温度磁性质透射电子显微镜磁各向异性常数纳米粒子生物医学技术交流磁化率

Subclinical carotid atherosclerosis predicts all-cause mortality and cardiovascular events in obese patients with negative exercise echocardiography

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World j.urnal of Cardiology 2019年第1期11卷 24-36页

作者： Rafael Vidal-Perez Raúl franco-Gutiérrez Alberto j.Pérez-Pérez Virginia franco-Gutiérrez Alberto Gascón-Vázquez Andrea López-López Ana María Testa-Fernández Carlos González-j.anatey Department of Cardiology Hospital Universitario Lucus Augusti Department of Otolaryngology Hospital Carmen y Severo Ochoa Faculty of Medicine University of Santiago de Compostela

BACKGROUND Obesity is a maj.r health problem due to its high prevalence. The relationship between obesity and cardiovascular disease is unclear. Some studies agree that certain conditions associated with obesity, such as physical inactivity or cardiovascular risk factors, are responsible for cardiovascular risk excess among obese people. Carotid intima-media thickness and carotid plaques(CP) have been associated with cardiovascular adverse events in healthy populations, and recent data suggest a higher prevalence of subclinical carotid atherosclerosis in obese and metabolically unhealthy patients. However, there are no studies correlating subclinical atherosclerosis and adverse events(AE) in obese *** To determine the association between carotid disease and AE in obese patients with negative exercise echocardiography(EE).METHODS From j.nuary 1, 2006 to December 31, 2010, 2000 consecutive patients with a suspicion of coronary artery disease were submitted for EE and carotid ultrasonography. Exclusion criteria included previous vascular disease, left ventricular ej.ction fraction < 50%, positive EE, significant valvular heart disease and inferior to submaximal EE. An AE was defined as all-cause mortality,myocardial infarction and cerebrovascular accident. Subclinical atherosclerosis was defined as CP presence according to Manheim and the American Society of Echocardiography *** Of the 652 patients who fulfilled the inclusion criteria, 226(34.7%) had body mass indexes ≥ 30 kg/m2, and 76 of them(33.6%) had CP. During a mean follow-up time of 8.2(2.1) years, 27 AE were found(11.9%). Mean event-free survival at 1, 5 and 10 years was 99.1%(0.6), 95.1%(1.4) and 86.5%(2.7), respectively. In univariate analysis, CP predicted AE [hazard ratio(HR) 2.52, 95% confidence interval(CI) 1.17-5.46; P = 0.019]. In multivariable analysis, the presence of CP remained a predictor of AE(HR 2.26, 95%CI 1.04-4.95, P = 0.041). Other predictors identified were glomerular

关键词： Carotid intima media thickness Carotid plaque Carotid disease Myocardial infarction Mortality Stroke Exercise stress echocardiography

Exploring DFT+U parameter space with a Bayesian calibration assisted by Markov chain Monte Carlo sampling

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npj.Computational Materials 2021年第1期7卷 1661-1669页

作者： Pedram Tavadze Reese Boucher Guillermo Avendaño-franco Keenan X.Kocan Sobhit Singh Viviana Dovale-Farelo Wilfredo Ibarra-Hernández Matthew B.j.hnson David S.Mebane Aldo H.Romero Department of Physics and Astronomy West Virginia UniversityMorgantownWVUSA Department of Mechanical and Aerospace Engineering West Virginia UniversityMorgantownWVUSA Department of Physics and Astronomy Rutgers UniversityPiscatawayNJUSA Facultad de Ingeniería Benemérita Universidad Autónoma de PueblaApdo.Postal J-39PueblaPue.72570México

The density-functional theory is widely used to predict the physical properties of ***,it usually fails for strongly correlated materials.A popular solution is to use the Hubbard correction to treat strongly correlated electronic ***,the values of the Hubbard U and j.parameters are initially unknown,and they can vary from one material to *** this semi-empirical study,we explore the U and j.parameter space of a group of iron-based compounds to simultaneously improve the prediction of physical properties(volume,magnetic moment,and bandgap).We used a Bayesian calibration assisted by Markov chain Monte Carlo sampling for three different exchange-correlation functionals(LDA,PBE,and PBEsol).We found that LDA requires the largest U *** has the smallest standard deviation and its U and j.parameters are the most transferable to other iron-based ***,PBE predicts lattice parameters reasonably well without the Hubbard correction.

关键词： materials Hubbard parameter