985 resultados para Cross-shore profile


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Real-time monitoring applications may be used in a wireless sensor network (WSN) and may generate packet flows with strict quality of service requirements in terms of delay, jitter, or packet loss. When strict delays are imposed from source to destination, the packets must be delivered at the destination within an end-to-end delay (EED) hard limit in order to be considered useful. Since the WSN nodes are scarce both in processing and energy resources, it is desirable that they only transport useful data, as this contributes to enhance the overall network performance and to improve energy efficiency. In this paper, we propose a novel cross-layer admission control (CLAC) mechanism to enhance the network performance and increase energy efficiency of a WSN, by avoiding the transmission of potentially useless packets. The CLAC mechanism uses an estimation technique to preview packets EED, and decides to forward a packet only if it is expected to meet the EED deadline defined by the application, dropping it otherwise. The results obtained show that CLAC enhances the network performance by increasing the useful packet delivery ratio in high network loads and improves the energy efficiency in every network load.

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RESUMO: O efluxo de compostos antimicrobianos é um mecanismo importante na multirresistência em bactérias. Bombas de efluxo codificadas em plasmídeos, como a QacA e a Smr, estão implicadas na susceptibilidade reduzida a biocidas, geralmente utilizados na prevenção e controlo de infecções nosocomiais, incluindo as causadas por estirpes de Staphylococcus aureus resistentes à meticilina (MRSA). Neste trabalho pretendeu-se avaliar a relevância de QacA e Smr no perfil de susceptibilidade dos isolados clínicos MRSA SM39 e SM52, que transportam os plasmídeos pSM39 e pSM52 com os determinantes qacA e smr, respectivamente. A actividade de efluxo das estirpes SM39 e SM39 curada (sem pSM39) e das estirpes SM52 e RN4220:pSM52 (estirpe susceptível RN4220 transformada com pSM52) foi caracterizada por: (1) determinação da concentração mínima inibitória (CMI) de biocidas, corantes e antibióticos, na ausência e presença dos inibidores de efluxo tioridazina, clorpromazina, verapamil e reserpina; e (2) fluorometria em tempo-real. A determinação de CMIs demonstrou que a actividade de efluxo mediada por QacA e Smr está envolvida na susceptibilidade reduzida aos biocidas e corantes testados, que incluíram o brometo de hexadeciltrimetilamónio, a cetrimida, o cloreto de benzalcónio, a berberina, o cloreto de dequalínio, a pentamidina e o brometo de etídeo. Os ensaios fluorométricos confirmaram a elevada actividade de efluxo presente nas estirpes com os genes qacA ou smr. A determinação de CMIs para antibióticos β-lactâmicos em conjunto com o teste da nitrocefina revelou a presença simultânea do gene qacA e de uma β-lactamase no plasmídeo pSM39. Este trabalho evidencia a importância das bombas de efluxo QacA e Smr na resistência a biocidas em estirpes MRSA e na sobrevivência destas estirpes em ambiente hospitalar e na comunidade, para além de destacar a questão da potencial co-resistência entre biocidas e antibióticos.--------------- ABSTRACT: Drug efflux has become an important cause of multidrug resistance (MDR) in bacteria. Plasmid-encoded MDR efflux pumps, such as QacA and Smr, are implicated in reduced susceptibility to biocides, generally used in the prevention and control of nosocomial infections, including the ones caused by methicillin-resistant Staphylococcus aureus (MRSA). In this work, we aimed to evaluate the relevance of QacA and Smr to the susceptibility profile of the clinical MRSA isolates SM39 and SM52, which harbor the plasmids pSM39 and pSM52 that carry the determinants qacA and smr, respectively. Efflux activity of strain SM39 and its plasmid-free counterpart, SM39 cured, SM52 and RN4220:pSM52 (susceptible strain RN4220 transformed with pSM52) was characterized by: (1) determination of minimum inhibitory concentration (MIC) of biocides, dyes and antibiotics, in the absence and presence of the efflux inhibitors thioridazine, chlorpromazine, verapamil and reserpine; and (2) real-time fluorometry. MIC determination showed that QacA and Smr mediated efflux was involved in the reduced susceptibility profile to the biocides and dyes tested, which included hexadecyltrymethylammonium bromide, cetrimide, benzalkonium chloride, berberine, dequalinium chloride, pentamidine and ethidium bromide. Fluorometric assays confirmed the higher efflux activity present in strains harboring qacA or smr genes. Moreover, MIC determination for β-lactam antibiotics together with the nitrocefin test confirmed the presence of a β-lactamase in the plasmid carried by SM39 strain, pSM39. This work highlights the relevance of QacA and Smr to the biocide resistance in MRSA strains, and consequently to their survival and maintenance in the hospital environment and in the community. Furthermore, the presence of a β-lactamase and qacA determinants in the the same plasmid reinforces the question of the potencial biocide/antibiotic co-resistance in MRSA strains.

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The aim of this study was to evaluate the epidemiological, clinical and laboratorial profile of patients with Baggio-Yoshinari Syndrome (BYS), who underwent internment at the Instituto de Infectologia Emilio Ribas in São Paulo, Brazil, during the period from July 1990 to July 2006. BYS is a new Brazilian tick-borne disease caused by Borrelia burgdorferi sensu lato microorganisms that resembles features of Lyme disease (LD), except for its epidemiological, clinical and laboratorial particularities. From 60 patients' records with positive serology to B. burgdorferi done by ELISA and Western-blotting methods, 19 cases were diagnosed as having BYS, according to criteria adopted at LIM-17 HCFMUSP, the Brazilian Reference Laboratory for the research of BYS. The other 41 remaining patients displayed miscellaneous infections or auto-immune processes. The beginning of symptoms in BYS group varied from one day to six years, from the onset of the disease. Four of 19 patients were included in acute disease stage, and 15 in latent. General unspecific symptoms were identified in almost all cases, with high frequencies of fever (78.9%) and lymphadenomegaly (36.8%). Six patients had skin lesions (31.5%); six arthralgia or arthritis (31.5%) and eight neurological symptoms (42%). Interestingly, two patients showed antibodies directed to B. burgdorferi exclusively in cerebrospinal fluid. Since BYS is a new emergent Brazilian zoonosis and its diagnosis is sometimes complex, all the new knowledge about BYS must be scattered to Brazilian Medical specialists, aiming to teach them how to diagnose this amazing tick-borne disease and to avoid its progression to chronic irreversible sequels

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This study describes the epidemiological profile of malaria in the State of Tocantins, in the period 2003-2008, investigates the association between the frequency of malaria and population growth, classifies the cases by 'autochthonous' and 'imported', reports the indices of the disease and analyses the distribution of the cases by Plasmodium species, age and gender. The retrospective study was based on secondary data, stored in SIVEP-malaria and analyzed using the software Epi-Info 3.5.1. and Bioestat 5.0. 19,004 samples were investigated for malaria, 19% of them were positive, 73.32% with Plasmodium vivax, 21.80% with Plasmodium falciparum, 4.79% with mixed infections and only 0.08% with Plasmodium malariae. Male individuals accounted for 76.95% and predominated in all years and age groups, especially in the 15 to 49 years old group. From the overall cases, 34.27% were autochthonous and 65.73% were imported (χ2 = 356.8, p = 0.0001). The frequency of malaria decreased significantly during the entire series (rp = 0.96, p = 0.002) and the number of municipalities with autochthonous transmission also diminished. It was found that malaria is predominantly imported, related to land activities, which confirms the need for effective measures to maintain vigilance throughout the state and enhance educational activities in order to guide the population towards early treatment-seeking.

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The environmental contamination by geohelminths represents a world public health problem and has been well documented by several authors. However, few papers describe the presence of such contamination in saline soils of coastal beaches. A study was performed on the beaches of the municipality of Santos in the period between May 2004 to April 2005 with the aim of determining the degree of contamination, and the correlation between contamination level and seasonal conditions and characteristics of the environment. Of the 2,520 samples analyzed, 18.2% (458) were contaminated, 32.3% (148) of which were localized in children's recreational areas (playgrounds). The parasite profile found in the analyzed samples indicated the presence of several zoonotic parasites: Ancylostoma larvae (82.5%), Toxocara sp. eggs (59.4%), Ancylostomidae-like eggs (37.1%), coccid oocysts (13.5%), Trichostrongylus sp. eggs and larvae, Ascaris lumbricoides eggs, (11.6%), Entamoeba sp. cysts (10.0%), Strongyloides sp. (4.8%), several free nematoids and some non-identified parasitic structures (3.3%). It was established that the highest frequency of parasitic structures occurred in the months between May and October 2004, and from February to March 2005. An increase in the diversity of parasitic forms was documented in the months between February to December 2004 and from January to April 2005, these periods having the highest rainfall.

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Old timber structures may show significant variation in the cross section geometry along the same element, as a result of both construction methods and deterioration. As consequence, the definition of the geometric parameters in situ may be both time consuming and costly. This work presents the results of inspections carried out in different timber structures. Based on the obtained results, different simplified geometric models are proposed in order to efficiently model the geometry variations found. Probabilistic modelling techniques are also used to define safety parameters of existing timber structures, when subjected to dead and live loads, namely self-weight and wind actions. The parameters of the models have been defined as probabilistic variables, and safety of a selected case study was assessed using the Monte Carlo simulation technique. Assuming a target reliability index, a model was defined for both the residual cross section and the time dependent deterioration evolution. As a consequence, it was possible to compute probabilities of failure and reliability indices, as well as, time evolution deterioration curves for this structure. The results obtained provide a proposal for definition of the cross section geometric parameters of existing timber structures with different levels of decay, using a simplified probabilistic geometry model and considering a remaining capacity factor for the decayed areas. This model can be used for assessing the safety of the structure at present and for predicting future performance.

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SUMMARY High-risk human papillomavirus (hr-HPV) infection is necessary but not sufficient for cervical cancer development. Recently, P16INK4A gene silencing through hypermethylation has been proposed as an important cofactor in cervical carcinogenesis due to its tumor suppressor function. We aimed to investigate P16INK4A methylation status in normal and neoplastic epithelia and evaluate an association with HPV infection and genotype. This cross-sectional study was performed with 141 cervical samples from patients attending Hospital Moncorvo Filho, Rio de Janeiro. HPV detection and genotyping were performed through PCR and P16INK4A methylation by nested-methylation specific PCR (MSP). HPV frequency was 62.4% (88/141). The most common HPV were HPV16 (37%), HPV18 (16.3%) and HPV33/45(15.2%). An upward trend was observed concerning P16INK4A methylation and lesion degree: normal epithelia (10.7%), low grade lesions (22.9%), high grade (57.1%) and carcinoma (93.1%) (p < 0.0001). A multivariate analysis was performed to evaluate an association between methylation, age, tobacco exposure, HPV infection and genotyping. A correlation was found concerning methylation with HPV infection (p < 0.0001), hr-HPV (p = 0.01), HSIL (p < 0.0007) and malignant lesions (p < 0.0001). Since viral infection and epigenetic alterations are related to cervical carcinoma, we suggest that P16INK4A methylation profile maybe thoroughly investigated as a biomarker to identify patients at risk of cancer.

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SUMMARY The aim of this study was to describe the epidemiological profile of snakebite accidents reported by the toxicological assistance center in Fortaleza, Ceará, Brazil. Database information on snakebite accidents was analyzed regarding the period from January 2003 to December 2011. A total of 1063 cases were found. The accidents occurred during the rainy months (March, April and May), in urban areas (52.3%), affecting individuals younger than 50 years and predominantly among males (70.7%). The lower limbs were the most frequently affected body area (33.7%). Most accidents involved non-venomous snakes (76.1%). The genus Bothrops was the main one involved in venomous accidents (83%). It is expected that this study can be used as the substrate to improve healthcare surveillance and implementing better measures for the treatment of this population.

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Objective: This study was designed to determine the frequency and causative agent(s) of urinary tract infections (UTIs) in individuals with symptoms of urinary tract infections in Enugu State of Southeast Nigeria, and to determine the antibiotic susceptibility pattern of microbial agents isolated from urine culture.Methods: The study involved 211 individuals (149 females and 62 males) clinically suspected for UTI. Urine samples were collected by the mid-stream ‘clean catch’ method and tested using standard procedures. Antibiotic susceptibility of the isolated pathogens was tested using the Kirby-Bauer technique according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.Results: Microscopy of centrifuged urine samples showed 16 patients had pyuria while 54 had pus cells. Calcium oxalate crystals were found in 14 samples. Urinalysis performed with urine samples showed 17 had protein; seven were nitrite positive and three had moderate to high glucose concentration. Fifty-four urine samples (36.2%) from females and 12 (19.4%) from males showed significant growth upon culture. Gram stain and biochemical tests identified nine different organisms with Escherichia coli as the most common isolated species. Forty three randomly selected strains were further tested for their susceptibility against a panel of antibiotics. Thirty isolates (81.08%) were resistant to four or more antibiotics with the highest resistance shown by E. coli (76.67%). All the Gram- negative isolates were resistant to Ampicilox, Cefuroxime and Amoxicillin.Conclusion: Urinary tract infections were found more in females in the area under study. As found in other studies, E. coli was the most predominant isolate, although other organisms seem to be on the increase.

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Enterococci are increasingly responsible for nosocomial infections worldwide. This study was undertaken to compare the identification and susceptibility profile using an automated MicrosScan system, PCR-based assay and disk diffusion assay of Enterococcus spp. We evaluated 30 clinical isolates of Enterococcus spp. Isolates were identified by MicrosScan system and PCR-based assay. The detection of antibiotic resistance genes (vancomycin, gentamicin, tetracycline and erythromycin) was also determined by PCR. Antimicrobial susceptibilities to vancomycin (30 µg), gentamicin (120 µg), tetracycline (30 µg) and erythromycin (15 µg) were tested by the automated system and disk diffusion method, and were interpreted according to the criteria recommended in CLSI guidelines. Concerning Enterococcus identification the general agreement between data obtained by the PCR method and by the automatic system was 90.0% (27/30). For all isolates of E. faecium and E. faecalis we observed 100% agreement. Resistance frequencies were higher in E. faecium than E. faecalis. The resistance rates obtained were higher for erythromycin (86.7%), vancomycin (80.0%), tetracycline (43.35) and gentamicin (33.3%). The correlation between disk diffusion and automation revealed an agreement for the majority of the antibiotics with category agreement rates of > 80%. The PCR-based assay, the van(A) gene was detected in 100% of vancomycin resistant enterococci. This assay is simple to conduct and reliable in the identification of clinically relevant enterococci. The data obtained reinforced the need for an improvement of the automated system to identify some enterococci.

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Neurocysticercosis (NCC) is one of the major causes of childhood seizures in developing countries including India and Latin America. In this study neurological pediatric cases presenting with afebrile seizures were screened for anti-Cysticercus antibodies (IgG) in their sera in order to estimate the possible burden of cysticercal etiology. The study included a total of 61 pediatric afebrile seizure subjects (aged one to 15 years old); there was a male predominance. All the sera were tested using a pre-evaluated commercially procured IgG-ELISA kit (UB-Magiwell Cysticercosis Kit ™). Anti-Cysticercus antibody in serum was positive in 23 of 61 (37.7%) cases. The majority of cases with a positive ELISA test presented with generalized seizure (52.17%), followed by complex partial seizure (26.08%), and simple partial seizure (21.73%). Headaches were the major complaint (73.91%). Other presentations were vomiting (47.82%), pallor (34.78%), altered sensorium (26.08%), and muscle weakness (13.04%). There was one hemiparesis case diagnosed to be NCC. In this study one child without any significant findings on imaging was also found to be positive by serology. There was a statistically significant association found between the cases with multiple lesions on the brain and the ELISA-positivity (p = 0.017). Overall positivity of the ELISA showed a potential cysticercal etiology. Hence, neurocysticercosis should be suspected in every child presenting with afebrile seizure especially with a radio-imaging supportive diagnosis in tropical developing countries or areas endemic for taeniasis/cysticercosis.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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Background: Genetic changes in influenza surface and internal genes can alter viral fitness and virulence. Mutation trend analysis and antiviral drug susceptibility profiling of A(H1N1)pdm09 viruses is essential for risk assessment of emergent strains and disease management. Objective: To profile genomic signatures and antiviral drug resistance of A(H1N1)pdm09 viruses and to discuss the potential role of mutated residues in human host adaptation and virulence. Study design: A(H1N1)pdm09 viruses circulating in Portugal during pandemic and post-pandemic periods and 2009/2010 season. Viruses were isolated in MDCK-SIAT1 cell culture and subjected to mutation analysis of surface and internal proteins, and to antiviral drug susceptibility profiling. Results: The A(H1N1)pdm09 strains circulating during the epidemic period in Portugal were resistant to amantadine. The majority of the strains were found to be susceptible to oseltamivir and zanamivir, with five outliers to neuraminidase inhibitors (NAIs) identified. Specific mutation patterns were detected within the functional domains of internal proteins PB2, PB1, PA, NP, NS1, M1 and NS2/NEP, which were common to all isolates and also some cluster-specific. Discussion: Modification of viral genome transcription, replication and apoptosis kinetics, changes in antigenicity and antiviral drug susceptibility are known determinants of virulence. We report several point mutations with putative roles in viral fitness and virulence, and discuss their potential to result in more virulent phenotypes. Monitoring of specific mutations and genetic patterns in influenza viral genes is essential for risk assessing emergent strains, disease epidemiology and public health implications.

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The objective was to validate Regulatory Sensory Processing Disorders’ criteria (DC:0-3R, 2005) using empirical data on the presence and severity of sensory modulation deficits and specific psychiatric symptoms in clinical samples. Sixty toddlers who attended a child mental health unit were diagnosed by a clinical team. The following two groups were created: toddlers with RSPD(N = 14) and those with ‘‘other diagnoses in Axis I/II of the DC:0-3R00(OD3R) (N = 46). Independently of the clinical process, parents completed the Infant Toddler Sensory Profile (as a checklist for sensory symptoms) and the Achenbach Behavior Checklist for ages 1/2–5 (CBCL 1/2–5). The scores from the two groups were compared. The results showed the following for the RSPD group: a higher number of affected sensory areas and patterns than in the OD3R group; a higher percentage of sensory deficits in specific sensory categories; and a higher severity of behavioral symptoms such as withdrawal, inattention, other externalizing problems and pervasive developmental problems in CBCL 1/2–5. The results confirmed our hypotheses by indicating a higher severity of sensory symptoms and identifying specific behavioral problems in children with RSPD. The results revealed convergent validity between the instruments and the diagnostic criteria for RSPD and supported the validity of RSPD as a unique diagnosis. The findings also suggested the importance of identifying sensory modulation deficits in order to develop an early intervention to enhance the sensory capacities of children who do not fully satisfy the criteria for some DSM-IV-TR disorders.