996 resultados para Unit vector fields


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The effectiveness of three operational strategies for the control of Triatoma dimidiata was compared by a field trial in the Department of Madriz, Nicaragua. One strategy involved full pretrial evaluation, followed by spraying of all houses irrespective of whether or not they had been found to be infested. The second strategy minimised the pretrial evaluation by considering the locality infested as soon as one house was found to be positive, followed by spraying all houses. The third strategy involved full pretrial evaluation, followed by spraying only those houses found to be positive. Evaluation after twelve months indicated that all three strategies were similarly effective, since all sprayed houses remained free of infestation. However, comparative estimates of the unit intervention costs indicated that strategies 1 and 2 were substantially less efficient than the third strategy of spraying only positive houses.

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DHSSPS Unit Cost Review Green Park Healthcare Trust

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The Flaviviridae is a family of about 70 mostly arthropod-borne viruses many of which are major public health problems with members being present in most continents. Among the most important are yellow fever (YF), dengue with its four serotypes and Japanese encephalitis virus. A live attenuated virus is used as a cost effective, safe and efficacious vaccine against YF but no other live flavivirus vaccines have been licensed. The rise of recombinant DNA technology and its application to study flavivirus genome structure and expression has opened new possibilities for flavivirus vaccine development. One new approach is the use of cDNAs encopassing the whole viral genome to generate infectious RNA after in vitro transcription. This methodology allows the genetic mapping of specific viral functions and the design of viral mutants with considerable potential as new live attenuated viruses. The use of infectious cDNA as a carrier for heterologous antigens is gaining importance as chimeric viruses are shown to be viable, immunogenic and less virulent as compared to the parental viruses. The use of DNA to overcome mutation rates intrinsic of RNA virus populations in conjunction with vaccine production in cell culture should improve the reliability and lower the cost for production of live attenuated vaccines. The YF virus despite a long period ignored by researchers probably due to the effectiveness of the vaccine has made a come back, both in nature as human populations grow and reach endemic areas as well as in the laboratory being a suitable model to understand the biology of flaviviruses in general and providing new alternatives for vaccine development through the use of the 17D vaccine strain.

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Molecular studies of insect disease vectors are of paramount importance for understanding parasite-vector relationship. Advances in this area have led to important findings regarding changes in vectors' physiology upon blood feeding and parasite infection. Mechanisms for interfering with the vectorial capacity of insects responsible for the transmission of diseases such as malaria, Chagas disease and dengue fever are being devised with the ultimate goal of developing transgenic insects. A primary necessity for this goal is information on gene expression and control in the target insect. Our group is investigating molecular aspects of the interaction between Leishmania parasites and Lutzomyia sand flies. As an initial step in our studies we have used random sequencing of cDNA clones from two expression libraries made from head/thorax and abdomen of sugar fed L. longipalpis for the identification of expressed sequence tags (EST). We applied differential display reverse transcriptase-PCR and randomly amplified polymorphic DNA-PCR to characterize differentially expressed mRNA from sugar and blood fed insects, and, in one case, from a L. (V.) braziliensis-infected L. longipalpis. We identified 37 cDNAs that have shown homology to known sequences from GeneBank. Of these, 32 cDNAs code for constitutive proteins such as zinc finger protein, glutamine synthetase, G binding protein, ubiquitin conjugating enzyme. Three are putative differentially expressed cDNAs from blood fed and Leishmania-infected midgut, a chitinase, a V-ATPase and a MAP kinase. Finally, two sequences are homologous to Drosophila melanogaster gene products recently discovered through the Drosophila genome initiative.

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We use historical data that cover more than one century on real GDP for industrial countries and employ the Pesaran panel unit root test that allows for cross-sectional dependence to test for a unit root on real GDP. We find strong evidence against the unit root null. Our results are robust to the chosen group of countries and the sample period. Key words: real GDP stationarity, cross-sectional dependence, CIPS test. JEL Classification: C23, E32

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iii. Catheter-related bloodstream infection (CR-BSI) diagnosis usually involves catheter withdrawal. An alternative method for CR-BSI diagnosis is the differential time to positivity (DTP) between peripheral and catheter hub blood cultures. This study aims to validate the DTP method in short-term catheters. The results show a low prevalence of CR-BSI in the sample (8.4%). The DTP method is a valid alternative for CR-BSI diagnosis in those cases with monomicrobial cultures (80% sensitivity, 99% specificity, 92% positive predictive value, and 98% negative predictive value) and a cut-off point of 17.7 hours for positivity of hub blood culture may assess in CR-BSI diagnosis.

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OBJECTIVE: To assess whether formatting the medical order sheet has an effect on the accuracy and security of antibiotics prescription. DESIGN: Prospective assessment of antibiotics prescription over time, before and after the intervention, in comparison with a control ward. SETTING: The medical and surgical intensive care unit (ICU) of a university hospital. PATIENTS: All patients hospitalized in the medical or surgical ICU between February 1 and April 30, 1997, and July 1 and August 31, 2000, for whom antibiotics were prescribed. INTERVENTION: Formatting of the medical order sheet in the surgical ICU in 1998. MEASUREMENTS AND MAIN RESULTS: Compliance with the American Society of Hospital Pharmacists' criteria for prescription safety was measured. The proportion of safe orders increased in both units, but the increase was 4.6 times greater in the surgical ICU (66% vs. 74% in the medical ICU and 48% vs. 74% in the surgical ICU). For unsafe orders, the proportion of ambiguous orders decreased by half in the medical ICU (9% vs. 17%) and nearly disappeared in the surgical ICU (1% vs. 30%). The only missing criterion remaining in the surgical ICU was the drug dose unit, which could not be preformatted. The aim of antibiotics prescription (either prophylactic or therapeutic) was indicated only in 51% of the order sheets. CONCLUSIONS: Formatting of the order sheet markedly increased security of antibiotics prescription. These findings must be confirmed in other settings and with different drug classes. Formatting the medical order sheet decreases the potential for prescribing errors before full computerized prescription is available.

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This study had the objective of to analyze the demographic and bacteriologic data of 32 hospitalized newborns in an neonatal intensive care unit of a public maternity hospital in Rio de Janeiro city, Brazil, seized by Pseudomonas aeruginosa sepsis during a period ranged from July 1997 to July 1999, and to determine the antimicrobial resistance percentage, serotypes and pulsed field gel electrophoresis (PFGE) patterns of 32 strains isolated during this period. The study group presented mean age of 12.5 days, with higher prevalence of hospital infection in males (59.4%) and vaginal delivery (81.2%), than females (40.6%) and cesarean delivery (18.8%), respectively. In this group, 20 (62.5%) patients received antimicrobials before positive blood cultures presentation. A total of 87.5% of the patients were premature, 62.5% presented very low birth weight and 40.6% had asphyxia. We detected high antimicrobial resistance percentage to b-lactams, chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline among the isolated strains. All isolated strains were classified as multi-drug resistant. Most strains presented serotype O11 while PFGE analysis revealed seven distinct clones with isolation predominance of a single clone (75%) isolated from July 1997 to June 1998.

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In 2009, the Sheffield Alcohol Research Group (SARG) at Sheffield University developed the Sheffield Alcohol Policy Model version 2.0 (SAPM) to appraise the potential impact of alcohol policies, including different levels of MUP, for the population of England. In 2013, SARG were commissioned by the DHSSPS and the Department for Social Development to adapt the Sheffield Model to NI in order to appraise the potential impact of a range of alcohol pricing policies. The present report represents the results of this work. Estimates from the Northern Ireland (NI) adaptation of the Sheffield Alcohol Policy Model - version 3 - (SAPM3) suggest: 1. Minimum Unit Pricing (MUP) policies would be effective in reducing alcohol consumption, alcohol related harms (including alcohol-related deaths, hospitalisations, crimes and workplace absences) and the costs associated with those harms. 2. A ban on below-cost selling (implemented as a ban on selling alcohol for below the cost of duty plus the VAT payable on that duty) would have a negligible impact on alcohol consumption or related harms. 3. A ban on price-based promotions in the off-trade, either alone or in tandem with an MUP policy would be effective in reducing alcohol consumption, related harms and associated costs. 4. MUP and promotion ban policies would only have a small impact on moderate drinkers at all levels of income. Somewhat larger impacts would be experienced by increasing risk drinkers, with the most substantial effects being experienced by high risk drinkers. 5. MUP and promotion ban policies would have larger impacts on those in poverty, particularly high risk drinkers, than those not in poverty. However, those in poverty also experience larger relative gains in health and are estimated to marginally reduce their spending due to their reduced drinking under the majority of policies åÊ

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Correspondence analysis was applied to sand fly sampling in 865 stations from the Western Mediterranean basin. The position of each of 24 species was determined with respect to the bioclimatic belts. Thus, the multidimensional analyses manifest clear correlations between bioclimatic belts and their expression in the area, the phytosociological groupings, and vector species of visceral and cutaneous leishmaniases. The transfer of these data to usual maps allows to delimit the geographical distribution of these diseases in the Western Mediterranean basin and contributes to the determination, in a rational manner, of the high risk zones.

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Treatment of cancer using gene therapy is based on adding a property to the cell leading to its elimination. One possibility is the use of suicide genes that code for enzymes that transform a pro-drug into a cytotoxic product. The most extensively used is the herpes simplex virus thymidine kinase (TK) gene, followed by administration of the antiviral drug ganciclovir (GCV). The choice of the promoter to drive the transcription of a transgene is one of the determinants of a given transfer vector usefulness, as different promoters show different efficiencies depending on the target cell type. In the experiments presented here, we report the construction of a recombinant adenovirus carrying TK gene (Ad-TK) driven by three strong promoters (P CMV IE, SV40 and EN1) and its effectiveness in two cell types. Human HeLa and mouse CCR2 tumor cells were transduced with Ad-TK and efficiently killed after addition of GCV. We could detect two sizes of transcripts of TK gene, one derived from the close together P CMV IE/SV40 promoters and the other from the 1.5 Kb downstream EN1 promoter. The relative amounts of these transcripts were different in each cell type thus indicating a higher flexibility of this system.

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The large spatial inhomogeneity in transmit B, field (B-1(+)) observable in human MR images at hi h static magnetic fields (B-0) severely impairs image quality. To overcome this effect in brain T-1-weighted images the, MPRAGE sequence was modified to generate two different images at different inversion times MP2RAGE By combining the two images in a novel fashion, it was possible to create T-1-weigthed images where the result image was free of proton density contrast, T-2* contrast, reception bias field, and, to first order transmit field inhomogeneity. MP2RAGE sequence parameters were optimized using Bloch equations to maximize contrast-to-noise ratio per unit of time between brain tissues and minimize the effect of B-1(+) variations through space. Images of high anatomical quality and excellent brain tissue differentiation suitable for applications such as segmentation and voxel-based morphometry were obtained at 3 and 7 T. From such T-1-weighted images, acquired within 12 min, high-resolution 3D T-1 maps were routinely calculated at 7 T with sub-millimeter voxel resolution (0.65-0.85 mm isotropic). T-1 maps were validated in phantom experiments. In humans, the T, values obtained at 7 T were 1.15 +/- 0.06 s for white matter (WM) and 1.92 +/- 0.16 s for grey matter (GM), in good agreement with literature values obtained at lower spatial resolution. At 3 T, where whole-brain acquisitions with 1 mm isotropic voxels were acquired in 8 min the T-1 values obtained (0.81 +/- 0.03 S for WM and 1.35 +/- 0.05 for GM) were once again found to be in very good agreement with values in the literature. (C) 2009 Elsevier Inc. All rights reserved.

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A parts based model is a parametrization of an object class using a collection of landmarks following the object structure. The matching of parts based models is one of the problems where pairwise Conditional Random Fields have been successfully applied. The main reason of their effectiveness is tractable inference and learning due to the simplicity of involved graphs, usually trees. However, these models do not consider possible patterns of statistics among sets of landmarks, and thus they sufffer from using too myopic information. To overcome this limitation, we propoese a novel structure based on a hierarchical Conditional Random Fields, which we explain in the first part of this memory. We build a hierarchy of combinations of landmarks, where matching is performed taking into account the whole hierarchy. To preserve tractable inference we effectively sample the label set. We test our method on facial feature selection and human pose estimation on two challenging datasets: Buffy and MultiPIE. In the second part of this memory, we present a novel approach to multiple kernel combination that relies on stacked classification. This method can be used to evaluate the landmarks of the parts-based model approach. Our method is based on combining responses of a set of independent classifiers for each individual kernel. Unlike earlier approaches that linearly combine kernel responses, our approach uses them as inputs to another set of classifiers. We will show that we outperform state-of-the-art methods on most of the standard benchmark datasets.

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The behavioural response of Triatoma pseudomaculata to chemical substances present in their faeces or cuticle (footprints) was analyzed. Groups of larvae were simultaneously exposed to a clean filter paper and to another paper impregnated with a chemical stimulus in a circular arena. In these choice experiments, the insects aggregated significantly around papers impregnated with dry faeces. In addition, the bugs also showed a significant aggregation response to papers impregnated with compounds derived from their cuticle that were deposited by contact on the substrate. These results indicate that chemical compounds that affect the behaviour of T. pseudomaculata are present in the faeces and in the cuticle of this species. Results are discussed in relation to chemical communication in the Triatominae, as well as to the potential use of these substances in traps or sensors for the detection of this species.