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Journal of Innovative Optical Health Sciences 2017年第6期10卷 3-16页

作者： Sara Mattana Silvia Caponi Francesco Tamagnini Daniele Fioretto Francesca Palombo department of physics and geology university of perugia Perugia I-06123Italy Istituto Officina dei Materiali del CNR(CNR-IOM)-Unita di perugia department of physics and geology university of perugia Perugia I-06123Italy Hatherly Laboratories Medical School University of ExeterExeter EX44PSUK School of physics and Astronomy university of Exeter Exeter EX44QLUK

A myloidopathy is one of the most prominent hallmarks of Alkheimer's disease(AD),the leading cause of dementia worldwide,and is characterized by the accumulation of amyloid plaques in the brain *** plaques consist of abnornal deposits mainly composed of an aggregation-prone protein fragment,B-amyloid 140/1-42,into the extracellular *** micro-spectroscopy is an all-optical contactless technique that is based on the interaction between visible light and longitudinal acoustic waves or phonons,giving access to the viscoelasticity of a sample on a subcellular ***,we describe the first application of micromechanical mapping based on Brillouin scattering spectroscopy to probe the stifness of individual amyloid plaques in the hippocampal part of the brain of a B-amyloid overexpressi ng transgenic *** analysis based on Brillouin and Raman microspectroscopy showed that amyloid plaques have a complex structure with a rigid core of B-pleated shoet conformation(B-aryloid)protein sur-rounded by a softer ring-shaped region richer in lipids and other protein *** preliminary results give a new insight into the plaque biophysics and biomechanics,and a valuable contrast mechanism for the study and diagnosis of amnyloidopathy.

关键词： Alzheimer's imaging vibrational spectrosecopy protein misfolding light scattering

Non-contact mechanical and chemical analysis of single living cells by microspectroscopic techniques

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Light(Science & Applications) 2017年第1期6卷 201-209页

作者： Sara Mattana Maurizio Mattarelli Lorena Urbanelli Krizia Sagini Carla Emiliani Mauro Dalla Serra Daniele Fioretto Silvia Caponi department of physics and geology University of PerugiaPerugia I-06123Italy Laboratory of Biochemistry and Molecular Biology Department of ChemistryBiology and BiotechnologyUniversity of Perugiavia del GiochettoPerugia I-06123Italy CEMIN-Center of Excellence for Innovative Nanostructured Material Perugia I-06123Italy Istituto di Biofisica CNR(IBF-CNR) Unitàdi Trentoand FBKVia Sommarive 18Trento 38123Italy Istituto Officina dei Materiali del CNR(CNR-IOM)-Unitàdi perugia c/o Department of Physics and GeologyUniversity of PerugiaPerugia I-06123Italy

Innovative label-free microspectroscopy,which can simultaneously collect Brillouin and Raman signals,is used to characterize the viscoelastic properties and chemical composition of living cells with sub-micrometric *** unprecedented statistical accuracy of the data combined with the high-frequency resolution and the high contrast of the recently built experimental setup permits the study of single living cells immersed in their buffer solution by contactless *** Brillouin signal is deconvoluted in the buffer and the cell components,thereby revealing the mechanical heterogeneity inside the *** particular,a 20%increase is observed in the elastic modulus passing from the plasmatic membrane to the nucleus as distinguished by comparison with the Raman spectroscopic *** line shape analysis is even more relevant for the comparison of cells under physiological and pathological *** oncogene expression,cells show an overall reduction in the elastic modulus(15%)and apparent viscosity(50%).In a proof-of-principle experiment,the ability of this spectroscopic technique to characterize subcellular compartments and distinguish cell status was successfully *** results strongly support the future application of this technique for fundamental issues in the biomedical field.

关键词： living single cell analysis mechanical properties Raman and Brillouin spectroscopy

Investigations　of　the　seismomagnetic　effect　in　the　geomagnetic　diurnal　variations

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Acta Seismologica Sinica(English Edition) 1994年第3期7卷 457-464页

作者：陈伯舫 department of physics and department of Geography and geology University of Hong Kong Hong Kong

In this paper we attempt to Abstract seismomagnetic signals from geomagnetic diurnal variations of three components in quiet days before and after great earthquakes. The method employed here is to examine the ratio of apparent depths between two geomagnetic observatories using the single-station Z/H method. We first estimate the apparent depth for the period of 24 h for two observatories which are located at almost the same latitude. Then we analyse the time changes of the apparent-depth-ratio between these stations. In the interval of 1962 1988, the time variation of apparent-depth-ratio between the Beijing and Lanzhou observatories seems to be related to the three great earthquakes occurred near Beijing. Roughly speaking, the anomalous change in apparentdepth-ratio appears to be positive before earthquake, and appears to be negative after earthquake.

关键词： geomagnetic S_q field single-station Z/H method deep conductivily seismomagnetic effect

Nuclear sphingomyelin in neurodegenerative diseases

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Neural Regeneration Research 2021年第10期16卷 2028-2029页

作者： Elisabetta Albi Alice V.Alessenko department of Pharmaceutical Science University of PerugiaPerugiaItaly Emanuel Institute of Biochemical physics Russian Academy of SciencesMoscowRussia

Introduction:Recently,sphingolipids(SphLs)have become increasingly appreciated as a family of molecules involved in the growth,differentiation,and death of the central nervous system *** disequilibrium among the different SphLs leads to changes in the neuronal cell physiology and induces the development of neurodegenerative diseases(Alessenko and Albi,2020).Sphingomyelin(SM),sphinganin(Sphn),sphingosine(Sph),sphingosine-1-phosphate(S1P)and ceramide(Cer)are the most well-studied group of SphLs responsible for neurodegeneration,as well as derived molecules such as glucosylceramide or cerebroside(GCer)and galactosylceramide(GalCer)and finally more complex molecules such as as gangliosides.

关键词： finally system sine

Evaluation of formation susceptibility and sand production potential in an offshore field,Niger Delta Basin,Nigeria

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Energy Geoscience 2024年第1期5卷 1-11页

作者： David O.Ubuara Yinka A.Olayinka Godwin O.Emujakporue Geoffrey C.Soronnadi-Ononiwu department of geology University of Port HarcourtNigeria Mease Energy Nigeria Limited Port HarcourtNigeria department of geology University of IbadanNigeria department of physics University of Port HarcourtNigeria

Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil *** vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta *** foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(GR),density(RHOB),compressional slowness(DTC),and shear slowness(DTS)*** the Areo oil field,two wells(well 001 and well 002)were *** evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale *** compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high *** maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the *** means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the *** Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi ***,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce *** findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored in

关键词： Wireline log Stress Geo-mechanicanical characterization Sand prediction Niger delta

Helical tomotherapy for duodenal adenocarcinoma in an elderly patient: A case report

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World Journal of Gastrointestinal Oncology 2017年第2期9卷 94-97页

作者： Valentina Lancellotta Giuseppe Russo Marco Lupattelli Martina Iacco Elisabetta Perrucci Claudio Zucchetti Lorenzo Falcinelli Cynthia Aristei Radiation Oncology Section Department of Surgical and Biomedical Sciences University of Perugia Perugia General Hospital Gastroenterology Division Perugia General Hospital Radiation Oncology Division Perugia General Hospital Medical physics Unit Perugia General Hospital

To evaluate the efficacy and feasibility of external beam radiotherapy(EBRT) for duodenal adenocarcinoma in an 84-year-old female who underwent EBRT(2.2 Gy/d for a total dose of 46.2 Gy) using helical tomotherapy(HT). Toxicity was evaluated on the National Cancer Institute's common toxicity criteria(CTCAE 3.0). The patient completed the treatment without G3-G4 toxicity. After 22-mo follow-up, she is alive and well, in complete remission with no late side effects. HT seems to be feasible and effective for duodenal adenocarcinoma in old to very old patients.

关键词： The elderly Duodenal carcinoma Helical tomotherapy Toxicity

The northern Qiangtang Block rapid drift during the Triassic Period:Paleomagnetic evidence

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Geoscience Frontiers 2019年第6期10卷 2313-2327页

作者： Yanan Zhou Xin Cheng Yiying Wu Vadim Kravchinsky Ruiqi Shao Weijie Zhang Bitian Wei Ruiyao Zhang Fanrong Lu Hanning Wu department of geology&State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China department of physics University of AlbertaABCanada

As one of the pivotal Gondwana-derived blocks,the kinematic history of the northern Qiangtang Block(in the Tibetan Plateau)remains unclear,mainly because quantitative paleomagnetic data to determine the paleoposition are ***,for this study,we collected 226 samples(17 sites)from Triassic sedimentary rocks in the Raggyorcaka and Tuotuohe areas of the northern Qiangtang Block(NQB).Stepwise demagnetization isolated high temperature/field components from the *** Early and Late Triassic datasets passed field tests at a 99%confidence level and were proved to be primary *** were calculated to be at 24.9°N and 216.5°E with A95=8.2°(N=8)for the Early Triassic dataset,and at 68.1 N,179.9 E with A(95)=5.6°(N=37)for the Late Triassic,the latter being combined with a coeval volcanic dataset published *** paleopoles correspond to paleolatitudes of14.3°S±8.2°and 29.9 N15.6°,*** previously published results,we reconstructed a three-stage northward drift process for the NQB.(1)The northern Qiangtang Block was located in the subtropical part of the southern hemisphere until the Early Triassic;(2)thereafter,the block rapidly drifted northward from southern to northern hemispheres during the Triassic;and(3)the block converged with the Eurasian continent in the Late ***^4800 km northward movement from the Early to Late Triassic corresponded to an average motion rate of^11.85 cm/*** rapid drift of the NQB after the Early Triassic led to a rapid transformation of the Tethys Ocean.

关键词： Northern Qiangtang block Paleomagnetism Plate tectonics Tethys ocean Tibetan plateau Triassic

^(57)Fe M?ssbauer spectroscopy study of organic rich sediments(source rocks) from test well CT-1, Chinnewala structure of Jaisalmer basin,India

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Geoscience Frontiers 2016年第5期7卷 793-798页

作者： R.P.Tripathi Beena Bhatia R.Sharma K.R.Patel S.S.Meena Girish Ganwani S.C.Mathur department of physics Jai Narain Vyas University Jodhpur 342 005 India department of geology Jai Narain Vyas University Jodhpur 342 005 India

^57Fe Mossbauer spectroscopic study was carried out on the organic rich sedimentary samples collected at different depth intervals from newly drilled test well Chinnewala Tibba-1（CT-1） located in Jaisalmer Petroliferous basin India. It is found that iron is mainly distributed in high spin Fe^3＋and Fe^2＋ state in clay minerals. The plot of Fe^2＋/（Fe^2＋＋ Fe^3＋） indicates the presence of poor redox conditions in the *** obtained are also compared with those already reported in the literature. This comparison shows that there may exist a correlation between prospecting of the basin, the redox environment in sediments and the nature of iron bearing minerals distributed in the sedimentary sequence.

关键词： Jaisalmer petroliferous basin Chinnewala Tibba structure ^57Fe Mossbauer spectroscopic study Source rocks Hydrocarbon prospecting

Role of Magmatism and Related-Exsolved Fluids during Ta-Nb-Sn Concentration in the Central Eastern Desert of Egypt:Evidences from Mineral Chemistry and Fluid Inclusions

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Journal of Earth Science 2023年第3期34卷 674-689页

作者： Mohamed Abd El Monsef Mabrouk Sami Fatma Toksoy‐Köksal Rainer Abart Martin Ondrejka Khaled MAbdelfadil geology department Faculty of ScienceTanta University31527 TantaEgypt geology department Faculty of ScienceMinia University61519 El-MiniaEgypt department of Geological Engineering Middle East Technical University06800 AnkaraTurkey department of Lithospheric Research University of Vienna1090 ViennaAustria department of Mineralogy Petrology and Economic GeologyComenius UniversityBratislavaSlovakia department of geology Faculty of ScienceSohag University82524 SohagEgypt department of physics and Earth Sciences Jacobs University28759 BremenGermany

The rare metals of Abu Dabbab area in the Central Eastern Desert of Egypt have been investigated for their mineralogy and conditions of precipitation using combination of EMPA and fluid inclusions studies,in order to delineate the source,mechanism of formation and evolutionary model for these economic ***(Ta-Nb-Sn)-bearing minerals at the Abu Dabbab area include columbite group minerals(CGMs),wodginite and *** both granitic intrusion and its enclosed quartz veins,most of zoned CGMs and cassiterite grains are commonly characterized by a well-developed twostage ***,columbite-(Mn)(CGM-Ⅰ)represents the early formed phase of CGMs that is characterized by high Mn#values(0.64-0.92)with quite low Ta#values(0.13-0.49).It was invaded by Ta-rich phases including tantalite-(Mn)(CGM-Ⅱ;Ta#=0.13-0.49)and wodginite,which contain high Ta_(2)O_(5)and SnO_(2)(17.91 wt.%).In regard to cassiterite,there are distinct compositional differences between the early-phase cassiterite(Cst-Ⅰ)and the late-phase one(Cst-Ⅱ),where the latter is enriched in Ta_(2)O_(5),Nb_(2)O_(5)and *** chemistry and textural criteria of the early stage CGM-Ⅰand Cst-Ⅰ,all are indicative of magmatic ***,the latter CGM-Ⅱ,wodginite and Cst-Ⅱwere influenced by the late magmatic Ta-rich *** inclusions microthermometry shows criteria of phase separation represented by both boiling and fluid *** initial fluid was supposed to be of magmatic origin(magmatic CH4),that was consequently influenced by fluid mixing/dilution with post-hydrothermal/meteoric water with respect to the decompression process during *** construction gave rise to an estimate P-T conditions(T=330-370℃,P=22-50 MPa).The fluid inclusions’microthermometry supports a transition between magmatic and late to post-hydrothermal activities in addition to surface-derived fluid(meteoric fluid?)in a part as main source for the polymetallic deposits.

关键词： columbite-group minerals wodginite cassiterite magmatic-hydrothermal fluid inclusion deposits Abu Dabbab

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Monitoring of TDS and conductivity in groundwater in the seismically active region in NW Himalayas,India

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Earthquake Science 2010年第3期23卷 295-299页

作者： Arvind Kumar Surinder Singh Bikramjit Singh Bajwa Sandeep Mahajan Rajeev Kalia Sunil Dhar department of physics Guru Nanak Dev University department of geology Govt.CollegeDharamsala

The earthquake precursors and earthquake prediction are the burning issue among the community of earth scientists and engineers. Studies of earthquake precursory phenomena since the last several decades have shown that significant geophysical and geochemical changes may occur prior to intermediate and large earthquakes （Hartmann and Levy, 2005; Yang et al, 2005; Einarsson et al, 2008; Italiano et al, 2008; Kumar et al, 2009）. Among the more intensely investigated geochemical phenomena there have been changes in the concentrations of dissolved ions and gases in groundwater as well as variations in the concentrations of crustal and mantle volatiles in ground gases.

关键词： TDS (total dissolved solids) conductivity earthquake precursor NW Himalayas