1,121 research outputs found

    The influence of shear‐velocity heterogeneity on ScS2/ScS amplitude ratios and estimates of Q in the mantle

    Full text link
    Regional waveforms of deep‐focus Tonga‐Fiji earthquakes indicate anomalous traveltime differences (ScS2‐ScS) and amplitude ratios (ScS2/ScS) of the phases ScS and ScS2. The correlation between the ScS2‐ScS delay time and the ScS2/ScS amplitude ratio suggests that shear wave apparent Q in the mantle below the Tonga‐Fiji region is highest when shear wave velocities are lowest. This observation is unexpected if temperature variations were responsible for the seismic anomalies. Using spectral element method waveform simulations for four tomographic models, we demonstrate that focusing and scattering of shear waves by long‐wavelength 3‐D heterogeneity in the mantle may overwhelm the signal from intrinsic attenuation in long‐period ScS2/ScS amplitude ratios. The tomographic models reproduce the trends in recorded ScS2‐ScS difference times and ScS2/ScS amplitude ratios. Although they cannot be ruled out, variations in shear wave attenuation (i.e., the quality factor Q) are not necessary to explain the data.Key PointsThe influence of complex 3‐D wave propagation in the mantle on ScS2/ScS amplitude ratiosScS2‐ScS difference times are delayed and ScS2/ScS amplitude ratios are high on Samoa indicating low wave speeds but no attenuationBody wave amplitudes may be useful for evaluating the accuracy of tomographic models and as complementary data in tomographic inversionsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134191/1/grl54786_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134191/2/grl54786.pd

    Analysis of histological frequency and pediatric cancer in RondĂŽnia, Western Amazonia (Brazil)

    Full text link
    Objective:Describe the histological and cancer frequency in children and adolescents attended at the Hospital de Base Dr. Ary Pinheiro and the Hospital de Barretos / RondĂŽnia, Western Amazonia, in the years 2014 and 2015. Method: This is a descriptive, quantitative and transverse study. We used a structured instrument containing a series of variables, such as gender, age, histological types, more frequent neoplasms, lymphomas, leukemias, among others. We asked The ComitĂȘ de Ética em Pesquisa em Seres Humanos (Research Ethics Committee) to dispense the Informed Consent Form because the study did not require intervention on the patient or collection of biological material, and no possibility of constraints on patients and their relatives. Results: From 75 cases, 32 (42.7%) were female and 43 (57.3%) were male. Regarding the distribution of patients according to the age group, 21 (28.0%) were younger than 4 years, 12 (16.0%), 5 to 9 years, 17 (22.6%) from 10 to 14 and 25 (33.4%) from 15 to 19. The most frequent histological types by gender were leukemias of myeloproliferative diseases and myelodysplastic diseases with 30% and 50% new cases in the period, followed by lymphomas and reticuloendothelial neoplasms with 16.65% and 20, 0% of the histological types in the period. Leukemia in the hematopoietic and reticuloendothelial system (C42) is the most frequent cancer in both, female and male gender, with 47.5% of cancers in the biennium. The second group of cancers in children from 0 to 19 years old and location of the primary tumor is the encephalon carcinoma (C71), with 11.25% of the new cases. Conclusions: The results presented with their proper nuances are in agreement with the data of studies carried out in Brazil and in other countries

    Grapevine varieties exhibiting differences in stomatal response to water deficit

    Get PDF
    Abstract. Knowledge on variety traits and physiological responses to stress is still scarce in Vitis vinifera L., limiting the optimisation of irrigation and breeding for high water use efficiency. We have characterised five grapevine varieties using thermal imaging, leaf gas exchange, leaf morphology and carbon isotope composition. Plants of the varieties Aragonez, Trincadeira, Cabernet Sauvignon, Syrah and Touriga Nacional were grown in field conditions. Two experiments were performed. In Experiment I (2006), vines of Aragonez and Trincadeira were either well irrigated (WI, 80% ETc), nonirrigated but rain fed (NI) or subjected to regulated deficit irrigation (RDI, 40% ETc) and studied along the summer season. In Experiment II (2006 and 2007), vines of the five varieties were subjected to RDI (30–40% ETc) and studied at veraison. In Experiment I, leaf temperature (Tleaf) correlated negatively with stomatal conductance (gs) and leaf water potential (Ypd). The inverse relationship between gs and Tleaf was highly significant in the afternoon. In Experiment II, the different genotypes showed different Tleaf for similar Ypd. Stomatal density did not correlate with gs suggesting that varieties have different stomatal control. Our results show that combined measurements of canopy temperature and Ypd can aid in better understanding of stomatal regulation in different grapevine varieties. Such variation in stomatal regulation should be taken into account in determining irrigation strategie

    Quantitative methods and studies of psychic disorders and job satisfaction of teachers of the prison system in the Amazon, Brazil

    Full text link
    Objective: To analyze the level of mental suffering and the level of job satisfaction in 85% of the teachers of the state education network who work in the prison units in the city of Porto Velho, Rondonia, Amazonia, Brazil. Method: This is a cross-sectional study; and for the data collection, three structured instruments were used: the sociodemographic questionnaire; the Self-Report-Questionnaire Questionnaire (SRQ-20), and the OSI-Occupational Stress Indicator Scale, Measured by Likert Scale. Results: The results showed that 12.5% of the teachers presented minor psychic disorders, considered as indicators of evidence of mental distress. Satisfaction in the work had indexes similar to those found in the literature, presenting the highest proportion in the intermediate variables, that is, their highest frequencies are in the range of some dissatisfaction, with 32.28%; and 32.04% with some satisfaction. The highest index of dissatisfaction is in the variable that refers to salary, with 29.4%. Conclusions: From the results, it is possible to indicate a possible association between job satisfaction and mental suffering. This study will provide great reflections on the teaching practice in prison units and will contribute to the occupational health of teachers working in prison units, allowing a rethinking of public policies in education and health in the context of the prison system

    Geoepidemiological Profile of Leprosy in RondĂŽnia, Brazil

    Full text link
    The research aimed to evaluate the geoepidemiological profile of leprosy and its spatially uneven production in the state of Rondonia in the period from 2011 to 2014, from the perspective of medical geography, identifying and performing mapping of critical areas of the spatial production of leprosy. The study it is quantitative, descriptive and retrospective research. Information System Diseases and Reportable - the database SINAN (Sistema de Informação de Agravos e Notificåveis) was used. For the clothing of thematic maps was used ArcGIS program. The research universe was created by the registration of all new cases of leprosy reported in the period from 2011 to 2014, living in Rondonia. The State of Rondonia had 2,972 (two thousand nine hundred seventy-two) new cases of leprosy in the period studied, respectively 827 new cases in 2011, 779 in 2012, 2013 686 and 2014 680, which corresponds to 5.24 detection rate in 2011 4.93 2012 3.96 3.88 2013 and 2014 and are classified as hyperendemic area with detection rate/average incidence of 4.50 per 10,000 inhabitants. Leprosy is present in virtually 100% of the municipalities of Rondonia

    Modulatory antimicrobial activity of Piper arboretum extracts (Zingiberaceae)

    Get PDF
    The side effects of certain antibiotics have been a recent dilemma in the medical arena. Due this fact, the necessity of natural product discovery could provide important indications against several pharmacological targets and combat many infectious agents. Piper arboreum Aub. (Piperaceae) has been used by Brazilian traditional communities against several illnesses including rheumatism, bronchitis, sexually transmitted diseases and complaints of the urinary tract. Medicinal plants are a source of several remedies used in clinical practice to combat microbial infections. In this study, ethanol extract and fractions of Piper arboreum leaves were used to assay antimicrobial and modulatory activity. The minimum inhibitory concentration (MIC) was determined using microdilution method of ethanol extract and fractions from the leaves of P. arboreum ranging between 8 and 1024 mgmL–1. The capacity of these natural products to enhance the activity of antibiotic and antifungal drugs was also assayed. In these tests, natural products were combined with drugs. The natural products assayed did not demonstrate any clinically relevant antimicrobial activity (MIC ³ 1024 mg mL–1). However, the modulation of antibiotic activity assay observed a synergistic activity of natural products combined with antifungal (such as nystatin and amphotericin B) and antibiotic drugs (such as amikacin, gentamicin and kanamycin). According to these results, these natural products can be an interesting alternative not only to combat infectious diseases caused by bacteria or fungi, but also to combat enhanced resistance of microorganisms to antibiotic and antifungal drugs

    Optimization Algorithms for Large-Scale Real-World Instances of the Frequency Assignment Problem

    Get PDF
    Nowadays, mobile communications are experiencing a strong growth, being more and more indispensable. One of the key issues in the design of mobile networks is the Frequency Assignment Problem (FAP). This problem is crucial at present and will remain important in the foreseeable future. Real world instances of FAP typically involve very large networks, which can only be handled by heuristic methods. In the present work, we are interested in optimizing frequency assignments for problems described in a mathematical formalism that incorporates actual interference information, measured directly on the field, as is done in current GSM networks. To achieve this goal, a range of metaheuristics have been designed, adapted, and rigourously compared on two actual GSM networks modeled according to the latter formalism. In order to generate quickly and reliably high quality solutions, all metaheuristics combine their global search capabilities with a local-search method specially tailored for this domain. The experiments and statistical tests show that in general, all metaheuristics are able to improve upon results published in previous studies, but two of the metaheuristics emerge as the best performers: a population-based algorithm (Scatter Search) and a trajectory based (1+1) Evolutionary Algorithm. Finally, the analysis of the frequency plans obtained offers insight about how the interference cost is reduced in the optimal plans.Publicad

    Factor Analysis and the Social Capital Index: A Study at the Brazil / Bolivia Border

    Full text link
    Objective: The study aimed to build the level of social capital by neighborhoods GuajarĂĄ-Mirim border region between the State of RondĂŽnia, Brazil and the Republic of Bolivia, which in recent years has been showing signs of social fragility due advance not virtuous practices. Method: This work made use of research in secondary bases as well as in primary bases. The tabulation of qualitative and quantitative data was performed in Excel (2010) and for their processing performance index construction purposes were calculated following the factorial analysis techniques presented by Hair et al. [19] Santana [20, 21]; and Choi [22]. For this, we made use of the statistical tool SPSS (Statistical Package for Social Sciences) for the construction of the indices of social capital. The correlation analysis process was done in Excel. results: It was observed that the capital reached regular levels in GuajarĂĄ-Mirim neighborhoods not observable, so correlations between the studied parameters, however, it needs to be further studied as factors such as the flooding of the Mamore river may have interfered in any way in the implementation process of the field survey to the residents of the city. It became clear that the municipality of GuajarĂĄ-Mirim suffers from serious social problems and that most problems are correlated with the increase in alcoholic beverage market in the city and use drugs. However, was not observed as the institutional arrangements are dealing with this problem, that is, as public bodies are relating to discuss actions for concrete solutions to this evil that plagues large portion of the population of GuajarĂĄ-Mirim, mainly young teenagers residents of GuajĂĄ-Mamim. However, we hope to continue this work in order to better understand this mechanism of social network between the actors of this process in the region
    • 

    corecore