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Optical properties of phosphate glasses co-doped with Yb^(3+) and silver nanoparticles

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Chinese Physics B 2014年第12期23卷 249-253页

作者： m.A.Vallejo H. m.A.martinez G. A.V.Kiryanov J.L.Lucio m. Centro de Investigaciones enóptica Loma del Bosque 115 Col.Lomas del CampestreLeón 37150 Guanajuato Mxico División de Ciencias e Ingenierías del Campus León de la Universidad de Guanajuato Loma del Bosque 103Col.Lomas del Campestre37150León Guanajuato Mxico

We report the fabrication and spectroscopic characterization of Yb^3＋-doped phosphate glass, also containing silver nitrate. Scanning electron microscopy（SEm） provides the evidence of the formation of silver nano-particles（SNPs）, which are formed as a consequence of melting and thermal decomposition of Ag NO3. Absorption spectra of the samples in the visible-to-near-infrared spectral range reveal the presence of bands centered at 410 nm associated with the SNP-plasmon resonance, and at 976 nm due to the Yb^3＋. Under 916-nm laser-diode pumping, the effect of the SNP reflects that： i） the fluorescence in the 950-nm–1150-nm spectral range is strongly enhanced（～ 30 times）, while the fluorescence decay time associated with the ^2F5/2→^2F7/2transition of Yb^3＋ increases 25%, and ii） the basic lasing properties（saturation pumping intensity, the emission and absorption cross sections） are substantially improved.

关键词： rare earths phosphate glasses silver nanoparticles

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脑动静脉畸形的7T非增强mR成像

国际医学放射学杂志 2016年第3期 326-327页

作者： K.H.Wrede P.Dammann S.Johst C.mnninghoff m.Schlamann S.maderwald 李志鹏 Erwin L.Hahn Institute for magnetic resonance Imaging University Duisburg-Essen

摘要目的前瞻性评估7 T mR时间飞跃(TOF)mRA和7 T非对比增强磁化准备快速梯度回波(mPRAGE)对颅内动静脉畸形(AVm)显示,并与1.5 T TOF mRA以及DSA做对比分析。方法招募20例具有单个或者多个AVm的病人,研究方案包括7 T和1.5 T的TOF mRA,以... 详细信息

摘要目的前瞻性评估7 T mR时间飞跃(TOF)mRA和7 T非对比增强磁化准备快速梯度回波(mPRAGE)对颅内动静脉畸形(AVm)显示,并与1.5 T TOF mRA以及DSA做对比分析。方法招募20例具有单个或者多个AVm的病人,研究方案包括7 T和1.5 T的TOF mRA,以及7 T的非对比增强mPRAGE序列,另外所有的病人都进行了4支血管的3D DSA检查。由2名放射科医生使用5点量表分析AVm以下

关键词： mRA 对比增强 TOF AVm mR

静脉注射钆塞酸二钠减少肝动脉期呼吸屏气能力的多中心随机安慰剂对照试验研究

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国际医学放射学杂志 2017年第2期 215-216页

作者： T.R.mc Clellan U.motosugi m.S.middleton B.C.Allen T.A.Jaffe C.m.miller 孙欢 Department of Radiology and Center for Advanced magnetic resonance Development Duke University Medical Center

摘要目的在多中心双盲安慰剂对照试验中,阐明最大肝动脉期呼吸屏气持续时间是否受注射钆塞酸二钠的影响。材料与方法本前瞻性多中心研究符合HIPAA并获得机构

关键词：钆塞酸二钠动脉期运动伪影对照试验

Recurrent ectopic pancreatitis of the jejunum and mesentery over a 30-year period

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 218-220页

作者： John CT Wong Charlotte Robinson Edward C Jones Alison Harris Charles Zwirewich Robert Wakefield Richard K Simons Eric m Yoshida Department of medicine Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Radiology Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Pathology and Laboratory medicine Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Surgery Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Division of Gastroenterology Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9

BACKGROUND:Ectopic pancreas is defined as pancreatic tissue found outside its usual anatomical position,with no ductal or vascular communication with the native pancreas. We describe a case of ectopic pancreas of the small bowel and mesentery causing recurrent episodes of pancreatitis, initially suspected on computed tomography(CT)and magnetic resonance cholangiopancreatography(mRCP),and confirmed on histological review of the resection. mETHODS:A 67-year-old woman presented with clinical symptoms and biochemical evidence of *** had similar episodes over the past 30 years with unrevealing investigations,and was concluded to have idiopathic pancreatitis. She underwent CT and mRCP,with findings suggestive of ectopic pancreas,a diagnosis confirmed on histology of the resection. RESULTS:mRCP identified a mass in the proximal small bowel mesentery isointense to the native pancreas,with a small duct draining into a proximal jejunal *** resected specimen consisted of normal parenchyma with lobulated acinar tissue with scattered islets of Langerhans,an occasional ductular structure,and admixed areas of adipose *** patient remained asymptomatic with normal biochemistry six months post-operatively. CONCLUSION:In an individual with abdominal pain,elevated serum amylase/lipase,but imaging findings of a normal native pancreas,ectopic pancreatitis should be considered,and can be evaluated by CT and mRCP.

关键词： ectopic pancreas gastrointestinal tract endoscopic ultrasound computed tomography magnetic resonance cholangiopancreatography

Biophysics of articular cartilage:What we can learn from spin relaxation?

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Biophysics of articular cartilage:What we can learn from spi...

morphometric analysis of facial and cochlear nerves in normal-hearing ears using 3D-CISS

第十七届国际生物物理大会;第十二届中国生物物理大会

作者： Konstantin I.momot R.mark Wellard Sabrina Barheine Alf Pawlik Jean-Philippe Ravasio Gary Cowin Chris Bell James m.Pope Faculty of Science and Technology Queensland University of TechnologyBrisbaneAustralia Faculte de medecine Universite Henri PoincareNancyFrance Centre for magnetic resonance University of QueenslandBrisbaneAustralia

Articular cartilage(AC) is a connective tissue covering the articulating surfaces of long *** structural basis is a biopolymeric extracellular matrix(ECm) based on collagen and *** provides a range of techniques for characterisation of the cartilage ECm and shows great promise for clinical diagnosis of *** research aims to develop mRI methodologies for studying the basic biophysics of articular cartilage,particularly the link between the macromolecular organisation of its ECm and load carriage.

关键词： mRI osteoarthritis Redfield relaxation theory biomechanics of cartilage

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Journal of Otology 2019年第4期14卷 136-140页

作者： meltem ?zdemir Rasime Pelin Kavak University of Health Sciences D??kap? Y?ld?r?m Beyaz?t Training and Research HospitalDepartment of Radiology

Purpose:The aim of the current study was to establish a normative data set for the morphometric parameters of the facial nevre(FN)and cochlear nevre(CN)according to age and sex in the adult population,using 3-dimensional constructive interference in steady state(3D-CISS)sequence on magnetic resonance ***:We retrospectively analyzed 157 ears of 102 adults with no hearing impairment,facial palsy or meniere's *** vertical(VD)and horizontal(HD)diameters as well as cross-sectional areas(CSAs)of the FNs and CNs were measured on the parasagittal oblique image created using the axial 3D-CISS sections passing through the internal acoustic *** related the measurement results with side,sex and ***:The mean VD,HD and CSA of the FNs were 1.09±0.18 mm,0.84±0.17 mm,and 0.75±0.27mm^2,respectively,whereas those of the CNs were 1.34±0.17 mm,1±0.15mm and 1.06±0.3mm^2,*** was no statistically significant difference between the morphometric parameters of both the nerves according to side or sex(P>0.05).However,except for the CSA of the FNs among males,we found a statistically significant decrease in all the morphometric parameters of both the nerves with ageing(Pmative morphometric data obtained in this study can be beneficial in clinical applications for sensorineural hearing loss,facial palsy and meniere's disease.

关键词： Cochlear nerve Facial nerve 3 dimensional constructive interference in steady state(3D-CISS)

Fast cross-linking by DOPA2 promotes the capturing of a stereospecific protein complex over nonspecific encounter complexes

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Biophysics Reports 2022年第Z1期8卷 239-252页

作者： Jian-Hua Wang Zhou Gong Xu Dong Shu-Qun Liu Yu-Liang Tang Xiaoguang Lei Chun Tang meng-Qiu Dong National Institute of Biological Sciences (NIBS) Tsinghua Institute of multidisciplinary Biomedical Research Tsinghua University State Key Laboratory of magnetic resonance and Atomic molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Yunnan University Beijing National Laboratory for molecular Sciences College of Chemistry and Molecular EngineeringCenter for Quantitative BiologyPeking-Tsinghua Center for Life SciencePeking University

Transient and weak protein–protein interactions are essential to many biochemical reactions, yet are technically challenging to study. Chemical cross-linking of proteins coupled with mass spectrometry analysis(CXmS) provides a powerful tool in the analysis of such interactions. Central to this technology are chemical cross-linkers. Here, using two transient heterodimeric complexes EIN/HPr and EIIAGlc/EIIBGlc as our model systems, we evaluated the effects of two amine-specific homo-bifunctional cross-linkers with different reactivities. We showed previously that DOPA2(di-ortho-phthalaldehyde with a di-ethylene glycol spacer arm) cross-links proteins 60–120 times faster than DSS(disuccinimidyl suberate). We found that though most of the intermolecular cross-links of either cross-linker are consistent with the encounter complexes(ECs), an ensemble of short-lived binding intermediates,more DOPA2 intermolecular cross-links could be assigned to the stereospecific complex(SC), the final lowest-energy conformational state for the two interacting proteins. Our finding suggests that faster cross-linking captures the SC more effectively and cross-linkers of different reactivities potentially probe protein–protein interaction dynamics across multiple timescales.

关键词： Chemical cross-linking mass spectrometry Transient protein–protein interaction Encounter complexes Stereospecific complex Cross-linker DOPA2 DSS

Cold adaptation does not alter ATP homeostasis during cold exposure in Drosophila melanogaster

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Integrative Zoology 2018年第4期13卷 471-481页

作者： Caroline m.WILLIAmS James R.ROCCA Arthur S.EDISON David B.ALLISON Theodore J.mORGAN Daniel A.HAHN Department of Integrative Biology University of CaliforniaBerkeleyCaliforniaUSA Departments of Entomology and Nematology University of FloridaGainesvilleFloridaUSA Biochemistry University of FloridaGainesvilleFloridaUSA Advanced magnetic resonance Imaging and Spectroscopy Facility McKnight Brain InstituteUniversity of FloridaGainesvilleFloridaUSA Departments of Genetics and Biochemistry Complex Carbohydrate Research CenterUniversity of GeorgiaAthensGeorgiaUSA Department of Epidemiology and Biostatistics School of Public HealthIndiana University BloomingtonBloomingtonIndianaUSA Division of Biology Kansas State UniversityManhattanKansasUSA

In insects and other ectotherms,cold temperatures cause a coma resulting from loss of neuromuscular function,during which ionic and metabolic homeostasis are progressively *** adaptation improves homeostasis during cold exposure,but the ultimate targets of selection are still an open *** acclimation and adaptation remodels mitochondrial metabolism in insects,suggesting that aerobic energy production during cold exposure could be a target of ***,we test the hypothesis that cold adaptation improves the ability to maintain rates of aerobic energy production during cold exposure by using^(31)P NmR on live *** lines of Drosophila melanogaster artificially selected for fast and slow recovery from a cold coma,we show that cold exposure does not lower ATP levels and that cold adaptation does not alter aerobic ATP production during cold ***-hardy and cold-susceptible lines both experienced a brief transition to anaerobic metabolism during cooling,but this was rapidly reversed during cold exposure,suggesting that oxidative phosphorylation was sufficient to meet energy demands below the critical thermal minimum,even in cold-susceptible *** thus reject the hypothesis that performance under mild low temperatures is set by aerobic ATP supply limitations in ***,excluding oxygen and capacity limitation as a weak link in energy *** work suggests that the modulations to mitochondrial metabolism resulting from cold acclimation or adaptation may arise from selection on a biosynthetic product(s)of those pathways rather than selection on ATP supply during cold exposure.

关键词： chill coma energetics insect oxygen limitation thermal tolerance

Silver Nanoparticles Supported on TiO_(2) and Their Antibacterial Properties:Effect of Surface Confinement and Nonexistence of Plasmon resonance

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materials Sciences and Applications 2014年第12期5卷 895-903页

作者： Zoe Vineth Quinones-Jurado miguel ángel Waldo-mendoza Hugo marcelo Aguilera-Bandin Edgar Giovanny Villabona-Leal Elsa Cervantes-González Elías Pérez Innovation and Development in Advanced materials POLYnnova GroupSan Luis PotosíMéxico A Schulman of méxico San Luis PotosíMéxico Institute of Physic Autonomous University of San Luis PotosíSan Luis PotosíMéxico Academic Coordination Altiplano RegionAutonomous University of San Luis PotosíSan Luis PotosíMéxico

Ag/TiO2 nanocomposites are usually regarded as an effective synergy for high antimicrobial performance under ultraviolet-visible light conditions. This study confirmed that the surface plasmon resonance of Ag NPs plays an important role in relation to the NPs size and consequently with the antibacterial effect of the nanocomposite. We observed that under visible light the reactivity of TiO2 cannot be amplified when it is supporting Ag NPs that have an inactive photocatalytically surface. The results confirmed that the antimicrobial effectiveness of nanocomposite based on Ag NPs supported-TiO2 is closely associated to the contact surface area and to the electronic performance of the noble metal.

关键词： Ag-TiO_(2) Antibacterial Silver Nanoparticles Surface Confinement