990 resultados para CAPACITANCE-VOLTAGE CHARACTERISTICS


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Project HR-3 of the Iowa Highway Research Board has been active since October 1, 1950. The project objective is the determination of flood discharge characteristics of small drainage areas. Funds for the project amount to $10,000 per year of which, by cooperative agreement, the Highway Commission and the U. S. Geological Survey each furnish $5,000. Previous reports have explained the set-up of the project and these explanations will not be repeated in this report.

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The prescription information (summary of product characteristics, SPC) is compiled by the pharmaceutical industry as required by the national regulatory authorities. They vary in their content about the properties of drugs and about the usefulness of therapeutic drug monitoring (TDM) in the blood of patients. Based on a previous study carried out in Germany, the degree of agreement of French SPC for 59 psychotropic drugs with the existing medico-scientific evidence in the area of TDM was examined using a recently developed instrument. A summary score of SPC content (SPCC) related to TDM (SPCC(TDM)) has been calculated and compared with the level of recommendation of TDM of the AGNP-TDM expert group consensus guidelines for TDM in psychiatry [AGNP: Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (Association for neuropsychopharmacology and pharmacopsychiatry)]. Among the antidepressants, antipsychotics, tranquillizers/hypnotic agents and mood stabilizers, the highest SPCC(TDM) scores in the French SPC were reached for imipramine (16), haloperidol (6), clonazepam (8) and lithium (23), respectively. Results were similar to those obtained from the analysis of German SPC, and considerable disagreement was found between the information on TDM in SPC and existing medico-scientific evidence, albeit less in the case of mood stabilizers. Taking into account the recommendations of the AGNP-TDM expert group guidelines, there is a deficit in the French SPC concerning TDM-relevant information. An amelioration of this situation could help to improve the clinical practice of TDM of psychotropic drugs, as the SPC is a widely used tool.

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This master thesis presents a research on the analysis of film tourism stakeholders in Catalonia applying the network analysis approach. The research aims to provide an analysis of the relations between local tourism stakeholders with local film offices through their websites. Therefore, the development of the present work involved the review of literature on the themes of film tourism and network analysis. Then the main stakeholders of film and tourism of Catalonia were identified and their websites analyzed. The measures indicators for network analysis such as centrality, closeness and betweenness degree have been applied on the analysis of the websites to determine the extent of the relations of film and tourism stakeholders in Catalonia. Results and conclusions are presented on the referred sections

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A discussion is presented of daytime sky imaging and techniques that may be applied to the analysis of full-color sky images to infer cloud macrophysical properties. Descriptions of two different types of skyimaging systems developed by the authors are presented, one of which has been developed into a commercially available instrument. Retrievals of fractional sky cover from automated processing methods are compared to human retrievals, both from direct observations and visual analyses of sky images. Although some uncertainty exists in fractional sky cover retrievals from sky images, this uncertainty is no greater than that attached to human observations for the commercially available sky-imager retrievals. Thus, the application of automatic digital image processing techniques on sky images is a useful method to complement, or even replace, traditional human observations of sky cover and, potentially, cloud type. Additionally, the possibilities for inferring other cloud parameters such as cloud brokenness and solar obstruction further enhance the usefulness of sky imagers

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Samples of both recycled and nonrecycled asphaltic concrete were extracted in increments by the Abson Recovery Method and the penetration of the asphalt from each increment determined. The recycled projects were plantsite operations containing various amounts of virgin gravel. Cored samples were taken from the pavements on Kossuth County roads that were constructed as recycled projects in 1975, 1976, and 1977. Cored samples were also taken from a Kossuth County paving project done in 1975, that was not recycled. Comparison mix samples from 1978 construction projects in Marshall and Woodbury Counties of non - recycled projects are included. The test data from the penetrations of the recovered asphalt indicates that mixing of the old and new asphalt occurs very extensively in the hot recycling process. In laboratory controlled conditions it is difficult to coat aggregates with different penetration asphalts and prevent them from mixing.

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Background: Nursing home short stays (NHSS) in the canton of Vaud have been introduced for respite care purpose. However, a growing number of older patients are urgently admitted from home (within 24h) or directly after hospital discharge (58% of all admissions in 2010). NHSS appears therefore as an increasingly important component of the health care system, but the characteristics of admitted patients have not been previously described. A better knowledge would contribute to identify specific care needs and enhance their care. Objectives: 1) To describe the characteristics of patients admitted in unplanned NHSS ( after hospital stay or urgently from home); 2) To determine living disposition 3-month after NHSS discharge. Method: Over a 18-month period, elderly patients with unplanned NHSS admission to 2 facilities in Lausanne were identified. Demographic, social, health, and functional data, as well as main reason for admission were collected. Death and place of living at 3-months were collected using the administrative database. Results: Overall, 114 patients (mean age 83.1 ± 6.2 years, 77% women, 84% living alone) were assessed, 80% being admitted from hospital. Mean score in Lawton's instrumental ADL before NHSS admission was 4.6 ± 2.5 and 69% of the patients were home care recipients (median number of weekly visits: 5 ± 3). Patients reported going out 4.2 ± 1.3 times/week and 56% reported at least one fall over the past year. Among the 91 patients coming from the hospital, main reason for admission was injury/limb immobilization (58%), recuperation (13%) and functional impairment in basic ADL (10%). Mean score at Katz's Basic ADL at admission was 3.7 ± 1.9. Overall, 90% of patients were identified with gait and balance impairment, 78% with cognitive impairment and 70% with polypharmacy (>6 different drugs). At 3-month after NHSS discharge (N = 92), 72% patients were living at home, 16% had been admitted to long term care, and 6% died. Among patients living at home at follow-up, 11% had been readmitted to hospital during the follow-up period. Conclusion: Older patients with unplanned NHSS admission show a high prevalence of functional, mobility, and cognitive impairments, as well as other geriatric syndromes. Specific measures should be considered during these stays to prevent further functional decline and, possibly, hospital readmission. Patients admitted with basic ADLs impairment might be candidate for higher levels of care (rehabilitation).

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Orientation: Research that considers the effects of individual characteristics and job characteristics jointly in burnout is necessary, especially when one considers the possibility of curvilinear relationships between job characteristics and burnout. Research purpose: This study examines the contribution of sense of coherence (SOC) and job characteristics to predicting burnout by considering direct and moderating effects. Motivation for this study: Understanding the relationships of individual and job characteristics with burnout is necessary for preventing burnout. It also informs the design of interventions. Research design, approach and method: The participants were 632 working adults (57% female) in South Africa. The measures included the Job Content Questionnaire, the Sense of Coherence Questionnaire and the Maslach Burnout Inventory. The authors analysed the data using hierarchical multiple regression with the enter method. Main findings: Job characteristics and SOC show the expected direct effects on burnout. SOC has a direct negative effect on burnout. Job demands and supervisor social support show nonlinear relationships with burnout. SOC moderates the effect of demands on burnout and has a protective function so that the demands-burnout relationship differs for those with high and low SOC. Practical/managerial implications: The types of effects, the shape of the stressor-strain relationship and the different contributions of individual and job characteristics have implications for designing interventions. Contribution/value add: SOC functions differently when combined with demands, control and support. These different effects suggest that it is not merely the presence or absence of a job characteristic that is important for well-being outcomes but how people respond to its presence or absence.

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Wet pavement friction is known to be one of the most important roadway safety parameters. In this research, frictional properties of flexible (asphalt) pavements were investigated. As a part of this study, a laboratory device to polish asphalt specimens was refined and a procedure to evaluate mixture frictional properties was proposed. Following this procedure, 46 different Superpave mixtures, one stone matrix asphalt (SMA) mixture and one porous friction course (PFC) mixture were tested. In addition, 23 different asphalt and two concrete field sections were also tested for friction and noise. The results of both field and laboratory measurements were used to develop an International Friction Index (IFI)-based protocol for measurement of the frictional characteristics of asphalt pavements for laboratory friction measurements. Based on the results of the study, it appears the content of high friction aggregate should be 20% or more of the total aggregate blend when used with other, polish susceptible coarse aggregates; the frictional properties increased substantially as the friction aggregate content increased above 20%. Both steel slag and quartzite were found to improve the frictional properties of the blend, though steel slag had a lower polishing rate. In general, mixes containing soft limestone demonstrated lower friction values than comparable mixes with hard limestone or dolomite. Larger nominal maximum aggregate size mixes had better overall frictional performance than smaller sized mixes. In addition, mixes with higher fineness moduli generally had higher macrotexture and friction.

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Iowa state, county, and city engineering offices expend considerable effort monitoring the state’s approximately 25,000 bridges, most of which span small waterways. In fact, the need for monitoring is actually greater for bridges over small waterways because scour processes are exacerbated by the close proximity of abutments, piers, channel banks, approach embankments, and other local obstructions. The bridges are customarily inspected biennially by the county’s road department bridge inspectors. It is extremely time consuming and difficult to obtain consistent, reliable, and timely information on bridge-waterway conditions for so many bridges. Moreover, the current approaches to gather survey information is not uniform, complete, and quantitative. The methodology and associated software (DIGIMAP) developed through the present project enable a non-intrusive means to conduct fast, efficient, and accurate inspection of the waterways in the vicinity of the bridges and culverts using one technique. The technique combines algorithms image of registration and velocimetry using images acquired with conventional devices at the inspection site. The comparison of the current bridge inspection and monitoring methods with the DIGIMAP methodology enables to conclude that the new procedure assembles quantitative information on the waterway hydrodynamic and morphologic features with considerable reduced effort, time, and cost. It also improves the safety of the bridge and culvert inspections conducted during normal and extreme hydrologic events. The data and information are recorded in a digital format, enabling immediate and convenient tracking of the waterway changes over short or long time intervals.

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Understanding the influence of pore space characteristics on the hydraulic conductivity and spectral induced polarization (SIP) response is critical for establishing relationships between the electrical and hydrological properties of surficial sedimentary deposits. Here, we present the results of laboratory SIP measurements on saturated quartz samples with granulometric characteristics ranging from fine sand to fine gravel. We alter the pore characteristics using three principal methods: (i) variation of the grain sizes, (ii) changing the degree of compaction, and (iii) changing the level of sorting. We then examine how these changes affect both the SIP response and the hydraulic conductivity. In general, the results indicate a clear connection between the applied changes in pore characteristics and the SIP response. In particular, we observe a systematic correlation between the hydraulic conductivity and the relaxation time of the Cole-Cole model describing the observed SIP effect for the whole range of considered grain sizes.

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The present study is an integral part of a broader study focused on the design and implementation of self-cleaning culverts, i.e., configurations that prevent the formation of sediment deposits after culvert construction or cleaning. Sediment deposition at culverts is influenced by many factors, including the size and characteristics of material of which the channel is composed, the hydraulic characteristics generated under different hydrology events, the culvert geometry design, channel transition design, and the vegetation around the channel. The multitude of combinations produced by this set of variables makes the investigation of practical situations a complex undertaking. In addition to the considerations above, the field and analytical observations have revealed flow complexities affecting the flow and sediment transport through culverts that further increase the dimensions of the investigation. The flow complexities investigated in this study entail: flow non-uniformity in the areas of transition to and from the culvert, flow unsteadiness due to the flood wave propagation through the channel, and the asynchronous correlation between the flow and sediment hydrographs resulting from storm events. To date, the literature contains no systematic studies on sediment transport through multi-box culverts or investigations on the adverse effects of sediment deposition at culverts. Moreover, there is limited knowledge about the non-uniform, unsteady sediment transport in channels of variable geometry. Furthermore, there are few readily useable (inexpensive and practical) numerical models that can reliably simulate flow and sediment transport in such complex situations. Given the current state of knowledge, the main goal of the present study is to investigate the above flow complexities in order to provide the needed insights for a series of ongoing culvert studies. The research was phased so that field observations were conducted first to understand the culvert behavior in Iowa landscape. Modeling through complementary hydraulic model and numerical experiments was subsequently carried out to gain the practical knowledge for the development of the self-cleaning culvert designs.

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BACKGROUND: The long-term outcome of antiretroviral therapy (ART) is not assessed in controlled trials. We aimed to analyse trends in the population effectiveness of ART in the Swiss HIV Cohort Study over the last decade. METHODS: We analysed the odds of stably suppressed viral load (ssVL: three consecutive values <50 HIV-1 RNA copies/mL) and of CD4 cell count exceeding 500 cells/μL for each year between 2000 and 2008 in three scenarios: an open cohort; a closed cohort ignoring the influx of new participants after 2000; and a worst-case closed cohort retaining lost or dead patients as virological failures in subsequent years. We used generalized estimating equations with sex, age, risk, non-White ethnicity and era of starting combination ART (cART) as fixed co-factors. Time-updated co-factors included type of ART regimen, number of new drugs and adherence to therapy. RESULTS: The open cohort included 9802 individuals (median age 38 years; 31% female). From 2000 to 2008, the proportion of participants with ssVL increased from 37 to 64% [adjusted odds ratio (OR) per year 1.16 (95% CI 1.15-1.17)] and the proportion with CD4 count >500 cells/μL increased from 40 to >50% [OR 1.07 (95% CI 1.06-1.07)]. Similar trends were seen in the two closed cohorts. Adjustment did not substantially affect time trends. CONCLUSIONS: There was no relevant dilution effect through new participants entering the open clinical cohort, and the increase in virological/immunological success over time was not an artefact of the study design of open cohorts. This can partly be explained by new treatment options and other improvements in medical care.

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In this work, zinc indium tin oxide layers with different compositions are used as the active layer of thin film transistors. This multicomponent transparent conductive oxide is gaining great interest due to its reduced content of the scarce indium element. Experimental data indicate that the incorporation of zinc promotes the creation of oxygen vacancies. In thin-film transistors this effect leads to a higher threshold voltage values. The field-effect mobility is also strongly degraded, probably due to coulomb scattering by ionized defects. A post deposition annealing in air reduces the density of oxygen vacancies and improves the fieldeffect mobility by orders of magnitude. Finally, the electrical characteristics of the fabricated thin-film transistors have been analyzed to estimate the density of states in the gap of the active layers. These measurements reveal a clear peak located at 0.3 eV from the conduction band edge that could be attributed to oxygen vacancies.

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Abstract :The contraction of the heart or skeletal muscles is mainly due to the propagation, through excitable cells, of an electrical influx called action potential (AP). The AP results from the sequential opening of ion channels that generate inward or outward currents through the cell membrane. Among all the channels involved, the voltage-gated sodium channel is responsible for the rising phase of the action potential. Ten genes encode the different isoforms of these channels (from Nav1.1 to Nav1.9 and an atypical channel named NavX). Nav1.4 and Nav1.5 are the main skeletal muscle and cardiac sodium channels respectively. Their importance for muscle and heart function has been highlighted by the description of mutations in their encoding genes SCN4A and SCNSA. They lead respectively to neuromuscular disorders such as myotonia or paralysis (for Nav1.4), and to cardiac arrhythmias that can deteriorate into sudden cardiac death (for Nav1.5).The general aim of my PhD work has been to study diseases linked with channels dysfunction, also called channelopathies. In that purpose, I investigated the function and the regulation of the muscle and cardiac voltage-gated sodium channels. During the two first studies, I characterized the effects of two mutations affecting Nav1.4 and Nav1.5 function. I used the HEK293 model cells to express wild-type or mutant channels and then studied their biophysical properties with the patch-clamp technique, in whole cell configuration. We found that the SCN4A mutation produced complex alterations of the muscle sodium channel function, that could explain the myotonic phenotype described in patients carrying the mutation. In the second study, the index case was an heterozygous carrier of a SCNSA mutation that leads to a "loss of function" of the channel. The decreased sodium current measured with mutated Nay 1.5 channels, at physiological temperature, was a one of the factors that could explain the observed Brugada syndrome. The last project aimed at identifying a new potential protein interacting with the cardiac sodium channel. We found that the protein SAP97 binds the three last amino-acids of the C-terminus of Na,, 1.5. Our results also indicated that silencing the expression of SAP97 in HEK293 cells decreased the sodium current. Sodium channels lacking their three last residues also produced a reduced INa. These preliminary results suggest that SAP97 is implicated in the regulation of sodium channel. Whether this effect is direct or imply the action of an adaptor protein remains to be investigated. Moreover, our group has previously shown that Nav1.5 channels are localized to lateral membranes of cardiomyocytes by the dystrophin multiprotein complex (DMC). This suggests that sodium channels are distributed in, at least, two different pools: one targeted at lateral membranes by DMC and the other at intercalated discs by another protein such as SAP97.These studies reveal that cardiac and muscle diseases may result from ion channel mutations but also from regulatory proteins affecting their regulation.Résumé :La contraction des muscles et du coeur est principalement due à la propagation, à travers les cellules excitables, d'un stimulus électrique appelé potentiel d'action (PA). C'est l'ouverture séquentielle de plusieurs canaux ioniques transmembranaires, permettant l'entrée ou la sortie d'ions dans la cellule, qui est à l'origine de ce PA. Parmi tous les canaux ioniques impliqués dans ce processus, les canaux sodiques dépendant du voltage sont responsables de la première phase du potentiel d'action. Les différentes isoformes de ces canaux (de Nav1.1 à Nav1.9 et NavX) sont codées par dix gènes distincts. Nav1.4 et Nav1.5 sont les principaux variants exprimés respectivement dans le muscle et le coeur. Plusieurs mutations ont été décrites dans les gènes qui codent pour ces deux canaux: SCN4A (pour Nav1.4) et SCNSA (pour Nav1.5). Elles sont impliquées dans des pathologies neuromusculaires telles que des paralysies ou myotonies (SCN4A) ou des arythmies cardiaques pouvant conduire à la mort subite cardiaque (SCNSA).Mon travail de thèse a consisté à étudier les maladies liées aux dysfonctionnements de ces canaux, aussi appelées canalopathies. J'ai ainsi analysé la fonction et la régulation des canaux sodiques dépendant du voltage dans le muscle squelettique et le coeur. A travers les deux premières études, j'ai ainsi pu examiner les conséquences de deux mutations affectant respectivement les canaux Nav1.4 et Nav1.5. Les canaux sauvages ou mutants ont été exprimés dans des cellules HEK293 afin de caractériser leurs propriétés biophysiques par la technique du patch clamp en configuration cellule entière. Nous avons pu déterminer que la mutation trouvée dans le gène SCN4A engendrait des modifications importantes de la fonction du canal musculaire. Ces altérations fournissent des indications nous permettant d'expliquer certains aspects de la myotonie observée chez les membres de la famille étudiée. Le patient présenté dans la deuxième étude était hétérozygote pour la mutation identifiée dans le gène SCNSA. La perte de fonction des canaux Nav1.5 ainsi engendrée, a été observée lors d'analyses à températures physiologiques. Elle représente l'un des éléments pouvant potentiellement expliquer le syndrome de Brugada du patient. La dernière étude a consisté à identifier une nouvelle protéine impliquée dans la régulation du canal sodique cardiaque. Nos expériences ont démontré que les trois derniers acides aminés de la partie C-terminale de Nav1.5 pouvaient interagir avec la protéine SAP97. Lorsque que l'expression de la SAP97 est réduite dans les cellules HEK293, cela induit une baisse importante du courant sodique. De même, les canaux tronqués de leurs trois derniers acides aminés génèrent un flux ionique réduit. Ces résultats préliminaires suggèrent que SAP97 est peut-être impliquée dans la régulation du canal Na,,1.5. Des expériences complémentaires permettront de déterminer si ces deux protéines interagissent directement ou si une protéine adaptatrice est nécessaire. De plus, nous avons préalablement montré que les canaux Nav1.5 étaient localisés au niveau de la membrane latérale des cardiomyocytes par le complexe multiprotéique de la dystrophine (DMC). Ceci suggère que les canaux sodiques peuvent être distribués dans un minimum de deux pools, l'un ciblé aux membranes latérales pax le DMC et l'autre dirigé vers les disques intercalaires par des protéines telles que SAP97.L'ensemble de ces études met en évidence que certaines maladies musculaires et cardiaques peuvent être la conséquence directe de mutations de canaux ioniques, mais que l'action de protéines auxiliaires peut aussi affecter leur fonction.