939 resultados para VP-SEM-EDS


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Precision Viticulture (PV) is a concept that is beginning to have an impact on the wine-growing sector. Its practical implementation is dependant on various technological developments: crop sensors and yield monitors, local and remote sensors, Global Positioning Systems (GPS), VRA (Variable-Rate Application) equipment and machinery, Geographic Information Systems (GIS) and systems for data analysis and interpretation. This paper reviews a number of research lines related to PV. These areas of research have focused on four very specific fields: 1) quantification and evaluation of within-field variability, 2) delineation of zones of differential treatment at parcel level, based on the analysis and interpretation of this variability, 3) development of Variable-Rate Technologies (VRT) and, finally, 4) evaluation of the opportunities for site-specific vineyard management. Research in these fields should allow winegrowers and enologists to know and understand why yield variability exists within the same parcel, what the causes of this variability are, how the yield and its quality are interrelated and, if spatial variability exists, whether site-specific vineyard management is justifiable on a technical and economic basis.

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Dels criteris proposats per la bibliogra a per identi car les perífrasis verbals (PV) de l'espanyol, només alguns ajuden a diferenciar amb e càcia les PV de les construccions no perifràstiques (CNP). L'objectiu d'aquest article és revisar aquests criteris i avaluar-los per tal de determinar quins són realment vàlids per identi car les PV. L'avaluació s'ha dut a terme amb un grup de 15 conjunts verbals. A més, s'ha realitzat un estudi experimental amb corpus per determinar la productivitat de les PV detectades.

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BACKGROUND: Transcranial magnetic stimulation combined with electroencephalogram (TMS-EEG) can be used to explore the dynamical state of neuronal networks. In patients with epilepsy, TMS can induce epileptiform discharges (EDs) with a stochastic occurrence despite constant stimulation parameters. This observation raises the possibility that the pre-stimulation period contains multiple covert states of brain excitability some of which are associated with the generation of EDs. OBJECTIVE: To investigate whether the interictal period contains "high excitability" states that upon brain stimulation produce EDs and can be differentiated from "low excitability" states producing normal appearing TMS-EEG responses. METHODS: In a cohort of 25 patients with Genetic Generalized Epilepsies (GGE) we identified two subjects characterized by the intermittent development of TMS-induced EDs. The high-excitability in the pre-stimulation period was assessed using multiple measures of univariate time series analysis. Measures providing optimal discrimination were identified by feature selection techniques. The "high excitability" states emerged in multiple loci (indicating diffuse cortical hyperexcitability) and were clearly differentiated on the basis of 14 measures from "low excitability" states (accuracy = 0.7). CONCLUSION: In GGE, the interictal period contains multiple, quasi-stable covert states of excitability a class of which is associated with the generation of TMS-induced EDs. The relevance of these findings to theoretical models of ictogenesis is discussed.

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Los materiales jarosíticos pueden encontrarse en estado natural (minerales de gossan) o generarse en circuitos hidrometalúrgicos. Para recuperar la plata contenida en estos materiales, se han propuesto procesos de descomposición alcalina-cianuración a temperaturas moderadas, elevadas o a presión, según el tipo de jarosita. En este trabajo se presenta un estudio sobre el tratamiento de soluciones sólidas jarosita-beudantita con sulfuros alcalinos a temperatura ambiente, seguido de cianuración convencional para la recuperación de la plata. Las transformaciones en estado sólido se han determinado mediante difracción de rayos X, microscopía óptica y electrónica (SEM-EDS) y microsonda electrónica. Durante la primera etapa del proceso, tiene lugar la descomposición de las fases jarosita, con formación de sulfuros de plomo y plata y un gel de hidróxido de hierro. La descomposición de potasiojarosita-beudantita tiene lugar a pH > 12 y la de beudantita-plumbojarosita, precisa de un valor más elevado (pH = 14). La oxidación posterior para eliminar el exceso de sulfuro, seguida de cianuración convencional, permite la recuperación de la plata contenida.

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Recientemente, MARTÍN-BLANCO & CARRASCO [Anales Jará Bot. Madrid 58(2): 355. 2001] enmendaban una cita anterior de Delphinium fissum subsp. sordidum de Ciudad Real, pero sin aclarar la identidad de la recolección. Explicaban que la planta -perenne, sin duda- no podía ser identificada como D. pentagynum ni como D. emarginatum subsp nevadense, los dos únicos táxones perennes del género entre los recopilados en Flora iberica [BLANCHÉ & MOLERO in CASTROVIEJO & al. (eds.), Fl. Iber. 1:242-251.1986]. Dudas similares habían sido expresadas anteriormente al atribuir a D. fissum subsp. sordidum una población de Almorchón (Badajoz) finalmente publicadas bajo este nombre [BLANCHÉ, Collect. Bot. {Barcelona) 16(1): 230-231.1985]. Todas estas interpretaciones se deben a la misma causa: las muestras estudiadas no tenían fruto ni, por ende, semillas.

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Se ha estudiado la lixiviación de concentrados de cobre con alto contenido de arsénico (hasta 2,5 %), mediante un proceso de oxidación con cloro formado 'in situ', por la reacción entre hipoclorito de sodio y ácido sulfúrico. El objetivo de estas experiencias es producir una solución de lixiviación, de características adecuadas para entrar a la etapa posterior de extracción por solventes (SX), es decir, entre 4 a 6 g/1 de cobre y 5 a 7 g/1 de ácido residual. Esta disolución, además, deberá contener cantidades mínimas de arsénico y cloruro. Las lixiviaciones se realizaron por agitación en un reactor de acrílico diseñado para tal efecto, a temperatura ambiente y a presión atmosférica. Se utilizaron concentrados de cobre de explotaciones mineras de Antofagasta (Chile). Se estudiaron algunas variables típicas de la lixiviación, como son: la concentración de agente lixiviante, el tiempo de lixiviación, el porcentaje de sólidos y la temperatura. La caracterización de algunos residuos sólidos, producto de las lixiviaciones, se realizó por DRX (Difracción de Rayos X) y EDS (Barrido de Energía Dispersiva de Rayos X). El cobre y arsénico en las disoluciones se analizaron mediante Espectroscopia de Absorción Atómica. Los resultados experimentales indican que es posible obtener soluciones de las características deseadas con este procedimiento, que utiliza reactivos comunes y de relativo bajo costo.

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We investigated the decayed historical church window glasses of two Catalonian churches, both under Mediterranean climate. Glass surfaces were studied by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). Their chemical composition was determined by avelength-dispersive spectrometry (WDS) microprobe analysis. The biodiversity was investigated by molecular methods: DNA extraction from glass, amplification by PCR targeting the16S rRNA and ITS regions, and fingerprint analyses by denaturing gradient gel electrophoresis (DGGE). Clone libraries containing either PCR fragments of the bacterial 16S rDNA or the fungal ITS regions were screened by DGGE. Clone inserts were sequenced and compared with the EMBL database.

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Ressenya de: Rafael Feito y Juan Ignacio López (eds.): Construyendo escuelas democráticas. Barcelona: Hipatia, 2008.

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Fiber-reinforced composite as oral implant material: Experimental studies of glass fiber and bioactive glass in vitro and in vivo Department of Prosthetic Dentistry and Biomaterials Science, Institute of Dentistry, University of Turku, Turku, Finland 2008. Biocompatibility and mechanical properties are important variables that need to be determined when new materials are considered for medical implants. Special emphasis was placed on these characteristics in the present work, which aimed to investigate the potential of fiber-reinforced composite (FRC) material as an oral implant. Furthermore, the purpose of this study was to explore the effect of bioactive glass (BAG) on osseointegration of FRC implants. The biocompatibility and mechanical properties of FRC implants were studied both in vitro and in vivo. The mechanical properties of the bulk FRC implant were tested with a cantilever bending test, torsional test and push-out test. The biocompatibility was first evaluated with osteoblast cells cultured on FRC substrates. Bone bonding was determined with the mechanical push-out test and histological as well as histomorplanimetric evaluation. Implant surface was characterized with SEM and EDS analysis. The results of these studies showed that FRC implants can withstand the static load values comparably to titanium. Threaded FRC implants had significantly higher push-out strength than the threaded titanium implants. Cell culture study revealed no cytotoxic effect of FRC materials on the osteoblast-like-cells. Addition of BAG particles enhanced cell proliferation and mineralization of the FRC substrates The in vivo study showed that FRC implants can withstand static loading until failure without fracture. The results also suggest that the FRC implant is biocompatible in bone. The biological behavior of FRC was comparable to that of titanium after 4 and 12 weeks of implantation. Furthermore, addition of BAG to FRC implant increases peri-implant osteogenesis and bone maturation.

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BACKGROUND: The objectives of this study were to determine the proportions of psychiatric and substance use disorders suffered by emergency departments' (EDs') frequent users compared to the mainstream ED population, to evaluate how effectively these disorders were diagnosed in both groups of patients by ED physicians, and to determine if these disorders were predictive of a frequent use of ED services. METHODS: This study is a cross-sectional study with concurrent and retrospective data collection. Between November 2009 and June 2010, patients' mental health and substance use disorders were identified prospectively in face-to-face research interviews using a screening questionnaire (i.e. researcher screening). These data were compared to the data obtained from a retrospective medical chart review performed in August 2011, searching for mental health and substance use disorders diagnosed by ED physicians and recorded in the patients' ED medical files (i.e. ED physician diagnosis). The sample consisted of 399 eligible adult patients (≥18 years old) admitted to the urban, general ED of a University Hospital. Among them, 389 patients completed the researcher screening. Two hundred and twenty frequent users defined by >4 ED visits in the previous twelve months were included and compared to 169 patients with ≤4 ED visits in the same period (control group). RESULTS: Researcher screening showed that ED frequent users were more likely than members of the control group to have an anxiety, depressive disorder, post-traumatic stress disorder (PTSD), or suffer from alcohol, illicit drug abuse/addiction. Reviewing the ED physician diagnosis, we found that the proportions of mental health and substance use disorders diagnosed by ED physicians were low both among ED frequent users and in the control group. Using multiple logistic regression analyses to predict frequent ED use, we found that ED patients who screened positive for psychiatric disorders only and those who screened positive for both psychiatric and substance use disorders were more likely to be ED frequent users compared to ED patients with no disorder. CONCLUSIONS: This study found high proportions of screened mental health and/or substance use disorders in ED frequent users, but it showed low rates of detection of such disorders in day-to-day ED activities which can be a cause for concern. Active screening for these disorders in this population, followed by an intervention and/or a referral for treatment by a case-management team may constitute a relevant intervention for integration into a general ED setting.

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This report has been written as part of the project “Toward improved quality – developing nurse’s continuing vocational training in hospitals and inpatient units”. Its overall goal is to ensure high quality, ethically appropriate and therapeutically effective interventions to enable nurses to manage distressed and disturbed patients in European psychiatric hospitals and inpatient units. In this large-scale, multinational projects there are all together six European countries involved: Finland, Ireland, England, Portugal, Italy and Lithuania. The project work plan were during autumn 2006 and spring 2007. The content of this publication was produced in the first stage of the project aiming to collect the preliminary source material for the project. The literature review was carried out in the project stage, providing the groundwork for the next steps for the project. This project aims to develop an interactive multinational portal with training material. Therefore, it is important to share an understanding of basic information, psychiatric nurse’s continuing vocational education, laws and ethical codes and patient restriction used in mental health care. In this publication, the purpose of the material produced here is to understand nurses’ educational need related to vocational continuing education and to be used in further project stages as an empirical data collection. The data were collected as a preliminary source material for latter phases where nurse’s perceptions of the current practice, nurse’s attitudes to mental illness, prevalence of use of seclusion room and existing and desired vocational training provision will be collected in six different European countries. The following organisations are involved in this project: University of Turku, Dublin City University, St. Vincent Hospital, National Council for the Professional Development of Nursing and Midwifery, University of Padova, Klaipeda College - Health Faculty, Klaipeda Psychiatric Hospital, Escola Superior de Enfermagem de Lisboa, Centro Hospitalar Psiquiátrico de Lisboa, Omnia Vocational Institution the Espoo Region, Kellokoski psychiatric hospital, Hyvinkää hospital area, Pirkanmaa Hospital District, Kingston University & St. George’s Medical School and South West London & St. George’s Mental Health NHS Trust. A wide variety of different countries, organisations and individuals in this project give us a strong confidence that theoretical, practical, ethical and political issues around the topic of interest will be taken account during this project lifetime. We are aware the content of this book will be partially outdated almost as soon as it has been published. We still hope that this publication will encourage nurses and different professions working in mental health care field to have a basic understanding of similarities and differences between different European countries related in mental health care. We also hope that this publication will inspirate and motivate nurses in maintaining and developing the quality of psychiatric care in Europe.