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Treatment of benign paroxysmal positional vertigo. A clinical review

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Journal of Otology 2017年第4期12卷 165-173页

作者： paz perez-Vazquez Virginia Franco-Gutierrez ENT Department Hospital Universitario de Cabuenes Gijon Spain ENT Department Hospital Universitario Marques de Valdecilla Santander Spain

Benign paroxysmal positional vertigo(BPPV) is the most frequent episodic vestibular disorder. It is due to otolith rests that are free into the canals or attached to the cupulas. Well over 90% of patients can be successfully treated with manoeuvres that move the particles back to the utriculus. Among the great variety of procedures that have been described, the manoeuvres that are supported by evidenced-based studies or extensive series are commented in this review. Some topics regarding BPPV treatment, such as controlling the accuracy of the procedures or the utility of post-manoeuvre restrictions are also discussed.

关键词： Benign Paroxysmal Positional Vertigo Treatment Vestibular disorder

Cattle change plant reproductive phenology,promoting community changes in a post-fire Nothofagus forest in northern Patagonia,Argentina

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Journal of Plant Ecology 2013年第6期6卷 459-467页

作者： Manuel de paz Estela Raffaele Laboratorio Ecotono INIBIOMACONICET-Universidad Nacional del ComahueQuintral 1250San Carlos de BarilocheRio Negro 8400Argentina

Aims Variations in rates and length of flowering and fruiting not only affect the reproduction of a given plant species but also the behavior and reproduction of associated *** and fruiting variations may be influenced by herbivory,especially by large *** aim of this study was to determine the effects of cattle browsing on the reproductive phenology of understory species in a subalpine post-fire Nothofagus forest in *** The effects of herbivory on plant reproductive phenology were studied in a set of experimental exclosures(fenced plots)installed since 2001 in a post-fire *** forest,located in Nahuel Huapi National Park(NHNP),*** monitored the beginning and duration of each reproductive phenological stage:floral bud,open flower,immature fruit and mature *** also counted the number of flowers,fruits,seeds and viable seeds of the dominant plants to assess whether browsing modifies temporal patterns of the flowering and fruiting *** Findings Cattle reduced the total number of species flowering and fruiting and changed the reproductive phenology of some *** found that palatable species seem to be negatively affected by browsing in terms of reduced fitness due to changes in flowering and fruiting *** contrast,cattle benefitted the reproduction of non-palatable species and could promote the invasion of shade-intolerant exotic forbs such as Cirsium *** effects of livestock reported in this study are important to understanding how browsing could alter native species establishment and possibly alter successional trajectories during recolonization after fire.

关键词： plant fitness livestock browsing flowering fruiting

Mid and late Holocene forest fires and deforestation in the subalpine belt of the Iberian range,northern Spain

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Journal of Mountain Science 2016年第10期13卷 1760-1772页

作者： Jose M.GARCIA-RUIZ Yasmina SANJUAN Graciela GIL-ROMERA Penelope GONZALEZ-SAMPERIZ Santiago BEGUERIA Jose ARNAEZ paz COBA-perez Amelia GOMEZ-VILLAR Javier ALVAREZ-MARTINEZ Noemi LANA-RENAULT Estela perez-CARDIEL Carlos LOPEZ DE CALLE Instituto Pirenaico de Ecologfa Consejo Superior de Investigaciones Cientificas(IPE-CSIC)Campus de Aula DeiP.O.Box 13.03450.080-ZaragozaSpain Estacion Experimental de Aula Dei Consejo Superior de Investigaciones Cientificas(EEAD-CSIC)Campus de Aula DeiP.O.Box 13.03450.080-ZaragozaSpain Area of Physical Geography University ofLa Rioja26.004-LogronoSpain Centro de Investigaciones en Geografia Ambiental Universidad Nacional Autonoma de MexicoUnidad MoreliaAntigua Carretera a Patzcuaro 870158190-MoreliaMichoacanMexico Departamento de Geografia y Geologia Faeultad de Filosofia y LetrasUniversidad de LeonCampus de Vegazana24.071-LeonSpain Departamento de Ingenieria Agricola y Forestal Universidad de ValladolidCampus La Yutera34.071-PalenciaSpain Department of Geography and Land Management University of Zaragoza50.009-ZaragozaSpain Freelance archaeologist Auda.Colon426003-LogronoSpain

The conversion of subalpine forests into grasslands for pastoral use is a well-knownphenomenon, although for most mountain areas the timing of deforestation has not been determined. The presence of charcoal fragments in soil profiles affected by shallow landsliding enabled us to date the occurrence of fires and the periods of conversion ofsubalpine forest into grasslands in the Urbión Mountains, Iberian Range, Spain. We found that the treeline in the highest parts of the northwestern massifs of the Iberian Range(the Urbión, Demanda, Neila, and Cebollera massifs) is currently between 1500 and 1600 m a.s.l., probably because of pastoral use of the subalpine belt, whereas in the past it would have reached almost the highest divides(at approximately 2100–2200 m a.s.l.). The radiocarbon dates obtained indicate that the transformation of the subalpine belt occurred during the Late Neolithic, Chalcolithic, Bronze Age, Iron Age, and Middle Ages. Forest clearing was probably moderate during fires prior to the Middle Ages, as the small size of the sheep herds and the local character of the markets only required small clearings, and therefore more limited fires. Thus, it is likely that the forest recovered burnt areas in a few decades; this suggests the management of the forest and grasslands following a slash-andburn system. During the Middle and Modern Ages deforestation and grassland expansion affected most of the subalpine belt and coincided with the increasing prevalence of transhumance, as occurred in other mountains in the Iberian Peninsula(particularly the Pyrenees). Although the occurrence of shallow landslides following deforestation between the Neolithic and the Roman Period cannot be ruled out, the most extensive shallow landsliding processes would have occurred from the Middle Ages until recent times.

关键词： Forest fires Holocene Subalpinegrasslands Shallow landslides Landscape changes Iberian Range

Seismic Policy, Operations, and Research Uses for a Building Inventory in an Earthquake-Prone City

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International Journal of Disaster Risk Science 2020年第6期11卷 709-718页

作者： Ken Elwood Olga Filippova Ilan Noy Jacob Pastor paz School of Engineering The University of AucklandAuckland 1142New Zealand Business School The University of AucklandAuckland 1142New Zealand School of Economics Victoria University of WellingtonWellington 6140New Zealand

After the 2016 New Zealand Kaikoura Earthquake,the absence of information about the state of buildings in Wellington proved to be a source of significant policy *** did not know what damages to expect and therefore how to react,and policies needed to be formulated without a clear quantification of the ***,without detailed knowledge of the existing buildings,it was difficult to assess what the available legal and regulatory tools can achieve and choose among *** describe the creation of a building inventory database for Wellington initiated by the *** database aims to assist the generation of research on the risks,impacts,and viable solutions for reducing future seismic risk in Wellington’s central business district(CBD).The database includes structural,economic,and market information on virtually every significant building in the *** primary purposes are:to collate and provide the best available information about the expected seismic performance of the existing building stock;to assess the impact of possible multiple building failures due to a seismic event;to describe a viable cost-effective path for seismic retrofitting;and to inform the design of a regulatory structure that can facilitate this resilience-building agenda.

关键词： Building inventory Building standards Disaster risk assessment Earthquake-prone city Retrofit

Cell membrane and bioactive factors derived from mesenchymal stromal cells: Cell-free based therapy for inflammatory bowel diseases

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World Journal of Stem Cells 2019年第9期11卷 618-633页

作者： Fabiany da Costa Goncalves Ana Helena paz Nephrology and Transplantation Internal MedicineErasmus Medical CenterRotterdamGD 3015Netherlands Experimental Research Center Hospital de Clínicas de Porto AlegrePorto AlegreRS 90035-903Brazil

Inflammatory bowel diseases(IBD)are chronic inflammatory disorders of the gastrointestinal tract associated with multifactorial conditions such as ulcerative colitis and Crohn’s *** the underlying mechanisms of IBD remain unclear,growing evidence has shown that dysregulated immune system reactions in genetically susceptible individuals contribute to mucosal ***,conventional treatments have been effective in inducing remission of IBD but not in preventing the relapse of *** this way,mesenchymal stromal cells(MSC)therapy has been recognized as a promising treatment for IBD due to their immunomodulatory properties,ability to differentiate into several tissues,and homing to inflammatory *** so,literature is conflicted regarding the location and persistence of MSC in the body after *** this reason,recent studies have focused on the paracrine effect of the biofactors secreted by MSC,especially in relation to the immunomodulatory potential of soluble factors(cytokines,chemokines,and growth factors)and extracellular vehicles that are involved in cell communication and in the transfer of cellular material,such as proteins,lipids,and nucleic ***,treatment with interferon-γ,tumor necrosis factor-α,and interleukin-1βcauses MSC to express immunomodulatory molecules that mediate the suppression via cell-contact dependent *** together,we present an overview of the role of bioactive factors and cell membrane proteins derived from MSC as a cell-free therapy that can improve IBD treatment.

关键词： Bioactive factors Cell membrane Mesenchymal stem cells Cell-free therapy Inflammatory bowel diseases

Novel aspects of the apolipoprotein-E receptor family： regulation and functional role of their proteolytic processing

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Frontiers in Biology 2012年第2期7卷 113-143页

作者： Jorge A. LARIOS Maria-paz MARZOLO Laboratorio de Trafico lntracelular y Senalizacion Departamento de Biologla Celular y Molecular Pontifieia Universidad Catolica de Chile Alameda # 340 Santiago Chile Millenium Nucleus in Regenerative Biology （MINREB） Facultad de Ciencias Biol6gieas Pontificia Universidad Catolica de Chile Alameda # 340 Santiago Chile

Studies related to the functional and regulatory aspects of proteolytic processing are of interest to cell biologists, developmental biologists and investigators who work on human diseases. Much of what is known about this topic derives from the study of the proteolytic processing of the amyloid precursor protein （APP）, which is involved in the pathology of Alzheimer＇s disease, and of the Notch protein and its Delta ligand, which play roles during embryonic development and in biologic processes in the adult. The proteolytic processing of plasma membrane receptor proteins is under the control of different enzymes that are responsible for releasing the ectodomain into the extracellular environment, where it has the potential to function as a signaling molecule and/or regulate the availability of the receptor＇s ligand. Following shedding of the ectodomain, the y-secretase enzymatic complex cleaves the transmembrane domain and releases the cytoplasmic domain （ICD） of the receptor. The ICD can function in the cytoplasm and/or at the nucleus. Members of the low-density lipoprotein receptor （LDLR） family are cndocytic-signaling proteins that perform a wide variety of physiologic functions during development and in the adult life. In addition these receptors have been implicated in a variety of diseases in adults. The prototypic receptor for this family of proteins is the LDLR itself. Besides their binding to apolipoproteins, these receptors bind many ligands that are destined for internalization and degradation. Some ligands have signaling properties. The proteolytic processing of certain members of the LDLR family not only controls receptor availability at the cell surface but also has functional consequences that amplify the spectrum of roles that these receptors perform. In addition, many complex regulatory mechanisms control the proteolytie processing of these receptors.

关键词： ADAM APP LDLR LRP metalloproteinase secretase

LJItrasensitive H2S gas sensors based on p-type WS2 hybrid materials

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Nano Research 2018年第8期11卷 4215-4224页

作者： Georgies Alene Asrest Jose J. Baldovi Aron Dombovari Topias Jarvinen Gabriela Simone Lorite Melinda Mohl Andrey Shchukarev alej.ndro perez paz Lede Xian Jyri-Pekka Mikkola Anita Lloyd Spetz Heli Jantunen Angel Rubio Krisztian Kordas Microelectronics Research Unit Faculty of Information Technology and Electrical Engineering University of Oulu P.O. Box 4S00FI-90014 Oulu Finland Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 149 22761 Hamburg Germany Nano-Bio Spectroscopy Group European Theoretical Spectroscopy Facifity (ETSF) Universidad del Pals Vasco CFM SCIC-UPV/EHU-MPC DIPC A venida Tolosa 72 20018 San Sebastian Spain Technical Chemistry Department of Chemistry Chemical-Biological Centre Umea University SE-90187 Umea Sweden School of Chemical Sciences and Engineering School of Physics and Nanotechnology Yachay Tech University Urcuquf Ecuador Industrial Chemistry & Reaction Engineering Department of Chemical Engineering Johan Gadolin Process Chemistry Centre AboAkademi University FI-20500 Abo-Turku Finland Sensor and Actuator Systems Department of Physics Chemistry and Biology Link~ping University SE-58183 LinkOping Sweden

Owing to their higher intrinsic electrical conductivity and chemical stability with respect to their oxide counterparts, nanostructured metal sulfides are expected to revive materials for resistive chemical sensor applications. Herein, we explore the gas sensing behavior of WS2 nanowire-nanoflake hybrid materials and demonstrate their excellent sensitivity （0.043 ppm-1） as well as high selectivity towards H2S relative to CO, NH~, H2, and NO （with corresponding sensitivities of 0.002, 0.0074, 0.0002, and 0.0046 pprn-1, respectively）. Gas response measurements, complemented with the results of X-ray photoelectron spectroscopy analysis and first-principles calculations based on density functional theory, suggest that the intrinsic electronic properties of pristine WS2 alone are not sufficient to explain the observed high sensitivity towards H2S. A major role in this behavior is also played by O doping in the S sites of the WS2 lattice. The results of the present study open up new avenues for the use of transition metal disulfide nanomaterials as effective alternatives to metal oxides in future applications for industrial process control, security, and health and environmental safety.

关键词： ws nanowire nanoflake gas sensor H2S,O doping

Stability of plane-parallel flow of magnetic fluids under external magnetic fields

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 295-310页

作者： P.Z.S.paz F.R.CUNHA Y.D.SOBRAL Department of Mathematics University of BrasíliaCampus Universitário Darcy RibeiroBrasília-DF70910-900Brazil Laboratory of Microhydrodynamics and Rheology-Vortex Group Department of Mechanical EngineeringUniversity of BrasíliaCampus Universitário Darcy RibeiroBrasília-DF70910-900Brazil

In this work,we present a theoretical study on the stability of a two-dimensional plane Poiseuille flow of magnetic fluids in the presence of externally applied magnetic *** fluids are assumed to be incompressible,and their magnetization is coupled to the flow through a simple phenomenological *** parameters are defined,and the equations are perturbed around the base *** eigenvalues of the linearized system are computed using a finite difference scheme and studied with respect to the dimensionless parameters of the *** examine the cases of both the horizontal and vertical magnetic *** obtained results indicate that the flow is destabilized in the horizontally applied magnetic field,but stabilized in the vertically applied *** characterize the stability of the flow by computing the stability diagrams in terms of the dimensionless parameters and determine the variation in the critical Reynolds number in terms of the magnetic ***,we show that the superparamagnetic limit,in which the magnetization of the fluids decouples from hydrodynamics,recovers the same purely hydrodynamic critical Reynolds number,regardless of the applied field direction and of the values of the other dimensionless magnetic parameters.

关键词： hydrodynamic stability magnetic fluid Orr-Sommerfeld equation magnetization evolution

Solving the inverse grating problem by white light interference Fourier scatterometry

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Light(Science & Applications) 2012年第1期1卷 17-23页

作者： Valeriano Ferreras paz Sandy Peterhansel Karsten Frenner Wolfgang Osten Institute of Applied Optics Stuttgart University70569 StuttgartGermany SCoPE—Stuttgart Research Center of Photonic Engineering Stuttgart UniversityStuttgartGermany

Scatterometry is a well-established,fast and precise optical metrology method used for the characterization of sub-lambda periodic *** Fourier scatterometry method,by analyzing the Fourier plane,makes it possible to collect the angle-resolved diffraction spectrum without any mechanical *** improve the depth sensitivity of this method,we combine it with white light *** show the exemplary application of the method on a silicon line *** characterize the sub-lambda features of the grating structures,we apply a model-based reconstruction approach by comparing simulated and measured *** simulations are based on the rigorous coupled-wave analysis method.

关键词： Fourier scatterometry inverse problem optical sub-lambda metrology RCWA white light interference