939 resultados para Yarkand (China)--History--Sources


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New emerging contaminants could represent a danger to the environment and Humanity with repercussions not yet known. One of the major worldwide pharmaceutical and personal care productions are antimicrobials products, triclosan, is an antimicrobial agent present in most products. Despite the high removal rate of triclosan present in wastewater treatments, triclosan levels are on the rise in the environment through disposal of wastewater effluent and use of sewage sludge in land application. Regulated in the EC/1272/2008 (annex VI, table 3.1), this compound is considered very toxic to aquatic life and it has been reported that photochemical transformation of triclosan produces dioxins. In the current work it was defined three objectives; determination of the most efficient process in triclosan degradation, recurring to photochemical degradation methods comparing different sources of light; identification of the main by-products formed during the degradation and the study of the influence of the Fenton and photo-Fenton reaction. Photochemical degradation methods such as: photocatalysis under florescent light (UV), photocatalysis under visible light (sunlight), photocatalysis under LEDs, photo-Fenton and Fenton reaction have been compared in this work. The degradation of triclosan was visualized through gas chromatography/mass spectrometry (GC/MS). In this study photo-Fenton reaction has successfully oxidized triclosan to H2O and CO2 without any by-products within 2 hours. Photocatalysis by titanium dioxide (TiO2) under LEDs was possible, having a degradation rate of 53% in an 8 hours essay. The degradation rate of the Fenton reaction, UV light and sunlight showed degradation between 90% and 95%. The results are reported to the data observed without statistic support, since this was not possible during the work period. Hydroquinone specie and 2,4-dichlorophenol by-products were identified in the first hour of photocatalysis by UV. A common compound, possibly identified has C7O4H , was present at the degradation by UV, sunlight and LEDs and was concluded to be a contaminant. In the future more studies in the use of LEDs should be undertaken given the advantages of long durability and low consumption of energy of these lamps and that due to their negative impact on the environment fluorescent lamps are being progressively made unavailable by governments, requiring new solutions to be found. Fenton and photo-Fenton reactions can also be costly processes given the expensive reagents used.

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En 1871, Edward Tylor rejeta fermement les récits de son temps qui niaient l'existence de croyances religieuses chez certains peuples alors considérés comme sauvages. C'était le cas, tout particulièrement, de l'explorateur victorien Samuel Baker, dont l'autorité ethnographique fut mise en cause à travers la citation de quelques voyageurs étrangers, dont deux français, qui avaient également observé les peuples nilotiques. Contrairement à d'autres sources de Primitive Culture, la qualité de ces ethnographies oubliées était, hélas, tout à fait médiocre ; mais elles permirent à Tylor de faire l'une des affirmations les plus décisives de son œuvre, celle de l'universalité de l'animisme. Ce passage capital - concernant des peuples qui deviendront célèbres dans l'histoire de l'anthropologie, à commencer par les Nuer - recèle par ailleurs une dimension additionnelle. Tylor voulait élargir à tout être spirituel les critères d'identification d'une religion, sauf que les ethnographes du Nil Blanc suggéraient que ces rudes populations croyaient bel et bien en un être suprême. Le dossier du monothéisme était comme anticipé par la force de ces données ; mais il ne faut pas y voir une contradiction de la part de Tylor. Au contraire, cette dialectique imprévue entre l'ethnographie et la théorie permet de mieux saisir la portée du concept d'animisme dont il fut le créateur.

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Introduction We attempted to supplement traditional insecticide spraying by treating peridomiciliar food sources with a powder formulation. Methods Two groups of houses were treated with deltamethrin suspension concentrate (SC), one of which had its primary peridomestic food sources treated with deltamethrin 2P. Results Triatoma brasiliensis was the most commonly captured triatomine. Birds, dogs and rodents were the major food sources identified by the precipitin reaction; 554 domestic animals received powder treatment. A sharp reduction in infestation rates was observed in the two groups up to 360 days after spraying. Conclusion The combination SC + 2P did not improve the control of triatomines.

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This report presents a case study to be used in courses of negotiation in masters and executive programs. The case studies the topics of the coalitions´ formation and stability from a negotiation analysis perspective, linking it to value creation. Moreover, it illustrates the problem of western companies investing in the Chinese market. The methodology utilized was the construction of a negotiation case, inspired by a real negotiation in the Consumer Electronics industry. Its purpose is to illustrate the value creation problems in coalitions. It is concluded that by maximizing value creation, negotiating parties are more likely to obtain stable coalitions

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Introduction The control of bacillary dysentery (BD) remains a big challenge for China. Methods Negative binomial multivariable regression was used to study relationships between meteorological variables and the occurrence of BD during the period of 2006-2012. Results Each 1°C rise of temperature corresponded to an increase of 3.60% (95%CI, 3.03% to 4.18%) in the monthly number of BD cases, whereas a 1 hPa rise in atmospheric pressure corresponded to a decrease in the number of BD cases by 2.85% (95%CI = 3.34% to 2.37% decrease). Conclusions Temperature and atmospheric pressure may be considered as predictors for the occurrence of BD in Guangzhou.

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FCT

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AbstractIn the last 15 years, different types of Triatominae resistance to different insecticides have been reported; thus, resistance may be more widespread than known, requiring better characterization and delimitation, which was the aim of this review. This review was structured on a literature search of all articles from 1970 to 2015 in the PubMed database that contained the keywords Insecticide resistance and Triatominae . Out of 295 articles screened by title, 33 texts were selected for detailed analysis. Insecticide resistance of Triatomines is a complex phenomenon that has been primarily reported in Argentina and Bolivia, and is caused by different factors (associated or isolated). Insecticide resistance of Triatominae is a characteristic inherited in an autosomal and semi-dominant manner, and is polygenic, being present in both domestic and sylvatic populations. The toxicological profile observed in eggs cannot be transposed to different stages of evolution. Different toxicological profiles exist at macro- and microgeographical levels. The insecticide phenotype has both reproductive and developmental costs. Different physiological mechanisms are involved in resistance. Studies of Triatomine resistance to insecticides highlight three deficiencies in interpreting the obtained results: I) the vast diversity of methodologies, despite the existence of a single guiding protocol; II) the lack of information on the actual impact of resistance ratios in the field; and III) the concept of the susceptibility reference lineage. Research on the biological and behavioral characteristics of each Triatominae species that has evolved resistance is required in relation to the environmental conditions of each region.

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FCT

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Chagas disease (CD) is a parasitic infection that originated in the Americas and is caused by Trypanosoma cruzi. In the last few years, the disease has spread to countries in North America, Asia and Europe due to the migration of Latin Americans. In the Brazilian Amazon, CD has an endemic transmission, especially in the Rio Negro region, where an occupational hazard was described for piaçaveiros (piassaba gatherers). In the State of Amazonas, the first chagasic infection was reported in 1977, and the first acute CD case was recorded in 1980. After initiatives to integrate acute CD diagnostics with the malaria laboratories network, reports of acute CD cases have increased. Most of these cases are associated with oral transmission by the consumption of contaminated food. Chronic cases have also been diagnosed, mostly in the indeterminate form. These cases were detected by serological surveys in cardiologic outpatient clinics and during blood donor screening. Considering that the control mechanisms adopted in Brazil's classic transmission areas are not fully applicable in the Amazon, it is important to understand the disease behavior in this region, both in the acute and chronic cases. Therefore, the pursuit of control measures for the Amazon region should be a priority given that CD represents a challenge to preserving the way of life of the Amazon's inhabitants.

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An ion emitter consisting of a sharp silver tip covered in RbAg4I5 solid electrolyte film has been developed and studied. An accelerating potential is applied and Ag+ ions are emitted from the tip’s apex by field evaporation. The emitted ions are collected by a Faraday cup, producing a current on the pico/nanoampere level which is read by an electrometer. The tips were produced mechanically by sandpaper polishing. The sharpest tip produced had a 2:4 m apex radius. Two deposition methods were studied: thermal vacuum and pulsed laser deposition. The best tip produced a peak current value of 96nA at 180oC, and a quasi-stable 4nA emission current at 160oC, both using an extraction potential of 10kV . The emission dependence on time, temperature and accelerating potential has been studied. Deposited films were characterized by X-ray diffraction (XRD), profilometry, optical and Scanning Electron Microscope (SEM) and Secondary Ion Mass Spectroscopy (SIMS) measurements. Several ion emitters were developed, the latter ones were all able to maintain stable high ion emissions for long periods of time. This investigation was a continuation of an ongoing project backed by the European Space Agency, with the objective of making a proof of concept of this kind of ion emitter with potential application on ion thrusters for orbiting satellites. Going forward, it would be interesting to make a finer analysis of the electrolyte’s conductivity at high temperatures, explore Wien Effect-based emission and to further develop a multi-tip ion emitter prototype.

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Abstract: INTRODUCTION: To provide information for cervical cancer screening and vaccination in Henan province, China, the distribution of human papillomavirus (HPV) was analyzed. METHODS: The HPV genotypes were detected using gene array and flow-through hybridization. RESULTS: Overall, 38.1% (1,536/4,033) of the women were human papillomavirus deoxyribonucleic acid (HPV DNA) positive. The prevalence of high-risk HPV types was 32.4%. HPV 16 was the most prevalent genotype (8.9%), followed by HPV 52 (5.8%) and HPV 58 (4.4%). CONCLUSIONS: The data support close surveillance of women for cervical cancer screening, and HPV prophylactic vaccines including HPV16, HPV 52, and HPV 58 might offer greater protection in this area.

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O objetivo deste estudo centra-se na análise e na comparação do contributo do petróleo do golfo da Guiné para a segurança energética dos EUA e da China no período 1990-2000, tendo presente a afirmação recente da região africana num quadro de escassez da matéria-prima. Foram elaborados três case studies visando caracterizar as potencialidades e riscos associados à região produtora e analisar o crescente envolvimento dos EUA e da China, através da implementação de políticas públicas conducentes à obtenção dos resultados visados e mediante o reforço da exposição da vertente empresarial. Os resultados obtidos traduziram-se no reforço do abastecimento dos EUA, mantendo uma posição ímpar perante o maior fornecedor regional, a Nigéria, enquanto a China assumiu posição de crescente relevância na região e sedimentou uma relação de grande preponderância face ao outro grande produtor, Angola. A existência de nexos de causalidade entre níveis de segurança energética e o recurso a instrumentos de políticas públicas é um domínio complexo, sendo de referir que o recurso ao economic statecraft pelos EUA, não afigura hipótese fundamentada enquanto fator explicativo das performances alcançadas por este país na região.

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Fundação para a Ciência e a Tecnologia (FCT), Fundação Millennium bcp, Imprensa Nacional-Casa da Moeda

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PURPOSE: Inspite of the long experience with the treatment of intermittent claudication, little is known about the natural history of stenotic lesions in the iliac segment. With the advent of endovascular treatment, this knowledge has become important. METHODS: Fifty-two stenosis, diagnosed using arteriography, in 38 claudicant patients were analyzed. After a minimum time interval of 6 months, a magnetic resonance angiography was performed to determine whether there was arterial occlusion. The primary factors that could influence the progression of a stenosis were analyzed, such as risk factors (smoking, hypertension, diabetes, sex, and age), compliance with clinical treatment, initial degree of stenosis, site of the stenosis, and length of follow-up. RESULTS: The average length of follow-up was 39 months. From the 52 lesions analyzed, 13 (25%) evolved to occlusion. When occlusion occurred, there was clinical deterioration in 63.2% of cases. This association was statistically significant (P = .002). There was no statistically significant association of the progression of the lesion with the degree or site of stenosis, compliance with treatment, or length of follow-up. Patients who evolved to occlusion were younger (P = .02). The logistic regression model showed that the determinant factors for clinical deterioration were arterial occlusion and noncompliance with clinical treatment. CONCLUSIONS: The progression of a stenosis to occlusion, which occurred in 25% of the cases, caused clinical deterioration. Clinical treatment was important, but it did not forestall the arterial occlusion. Prevention of occlusion could be achieved by early endovascular intervention or with the development of drugs that might stabilize the atherosclerotic plaque.