936 resultados para high fix-rate GPS
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ntestinal aspergillosis is an infection with a very high death rate especially in leukemic patients. Here we describe a case of a 46 years old woman with acute myeloid leukemia (LAM M5) who developed intestinal primary aspergillosis. This patient was diagnosed with LAM M5 through bone marrow aspiration and bone biopsy in March 2004. Symptoms of the disease were slight persistent fever, weight loss, asthenia, anemia, thrombocytopenia,and leukocytosis with high number of blasts in peripheral blood. After induction chemotherapy with ICE (Ifosfamide, Carboplatin, Etoposide), she developed neutropenia and high fever without apparent infective foci. She was treated with empiric antibiotic therapy, nevertheless she developed an intense diarrhea and ileo-cecal distention. Diagnostic exams didn’t show signs of a focal lesion. Despite the change in antibiotic treatment and the transfusions of granulocytes and blood cells, the patient developed extremely critical conditions with persistence of neutropenia and abdominal distention. A surgical treatment was decided at the time. We treated the patient with a two steps surgical procedure. The first step was a right abdominal ileostomy followed by improvement of general conditions and then the second step a right colectomy. The histological morphology confirmed necrotizing colitis with Aspergillus ife. At that time , treatment with voriconazole was started. The general conditions of the patient improved rapidly and we were able to treat the patient with other medical anti-leukemic therapies. The patient is now cured and in healthy state. We obtained a good clinical result as only in other few cases described in literature.
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Introduction. Breast phyllodes tumors (PT) are uncommon fibroepithelial lesions having potential malignant features. These tumors have characteristic features, like phleomorphism, mitoses and overgrowth of the stroma with possible infiltrative margins. The clinical behaviour could be unpredictable, since the relatively high recurrence rate despite correct surgical strategy. Conventional diagnostic examinations show high sensitivity and specificity, but cannot demonstrate the differences between benign and malignant PT. MRI is not more effective. Patients and methods. Sixteen patients affected by PT have been surgically treated at our Institution. All patients received mammography and ultrasonography (US) as preoperative diagnostic work-up. Results. in 13 patients, US was effective in preoperative diagnosis of PT. Mammography was uneffective in detecting breast lesions in 5 cases, while in 11 cases mammographic findings presented benign features, with a round opacity with moderate tissue density and well-defined wall. Conclusion. US remains the most useful diagnostic test in detecting PT. However, there is no test effective in identifying malignat PT. In case of suspicion, fine needle biopsy should be performed.
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A presente investigação situa-se na área da integração da Educação Profissional com Educação Básica na Modalidade de Jovens e Adultos (PROEJA) e busca a compreensão das vivências dos estudantes do curso no Câmpus Rio Grande que integra o Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul (IFRS-RG). Faz parte também dos objetivos identificar as contribuições do curso para a socialização desses estudantes e os significados atribuídos ao curso. Em função da elevada taxa de evasão, a pesquisa foi desenvolvida com estudantes que não concluíram o curso. A hermenêutica filosófica constitui-se na epistemologia que ancora teoricamente a abordagem metodológica. A Análise Textual Discursiva foi a metodologia qualitativa adotada para a análise do material empírico constituído centralmente pelas histórias contadas pelos estudantes. Eles contam sua passagem pelo PROEJA, desde o ingresso até a sua evasão. Foram produzidos dados quantitativos além de levantamentos para conhecer o contexto da trajetória escolar dos estudantes. Esses elementos subsidiaram a análise qualitativa das informações. Como resultados foram encontradas: uma taxa de evasão geral da ordem de 57%. Nos dois primeiros módulos ocorreu 87 % de toda a evasão do curso. Em todo o período de oferecimento do curso, ou seja sete anos, apenas três estudantes concluíram o mesmo. Pela análise qualitativa, emergiram cinco categorias que tratam: a) do ingresso no PROEJA e dos desencontros nesse processo; b) do estudante com suas peculiaridades, dificuldades e significados; c) do ser professor no PROEJA; d) do curso pelo viés da formação integrada; e) dos componentes constituintes da evasão. Como conclusões a pesquisa aponta para a inadequação do curso em seus diversos aspectos. Reforça que a construção curricular adaptada de um curso existente foi um equívoco. A formação dos professores e gestores promoveu a proposta de um curso repleto de contradições. Mesmo com todos os distanciamentos, o curso promoveu um ensino de qualidade na formação humana e por isso os estudantes desenvolveram sentimentos positivos quanto ao curso. Promoveu os estudantes a novas oportunidades na sua vida social, inclusive com ingresso na universidade. A tese geral aponta para a potencialidade do PROEJA do Câmpus Rio Grande, na transformação da realidade do sujeito, apesar do alto índice de evasão e da inadequação do curso.
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Se realizó un estudio descriptivo- retrospectivo desde enero de 2007 a diciembre del 2011. El universo estuvo constituido por los pacientes de 18 años y más con diagnóstico de Neumotórax, internados en los departamentos de cirugía del Hospital Regional Vicente Corral Moscoso y Hospital Teófilo Dávila. Para el levantamiento de la información se utilizó un formulario previamente diseñado. Los datos se transcribieron de las historias clínicas a los formularios respectivos. Resultados: Se incluyeron 73 pacientes del HTD y 52 del HVCM, el neumotórax de mayor prevalencia fue el traumático con el 85.6% de los casos, izquierdo en el 54.4%; las características clínicas de mayor relevancia fueron: dolor moderado 40.8%; taquicardia 15.2%; desviación de la tráquea hacia la derecha 32.8%; distención de las venas del cuello 38.4%; hipersonoridad 76.8%; murmullo vesicular disminuido 80%; disnea 99.2%; cianosis 22.4%; los método diagnósticos presentaron la siguiente prevalencia: radiografía de tórax 100%; tomografía 27.2% y resonancia en el 0.8% de los casos; el tratamiento fue en el 16% toracocentesis con aspiración de aguja y en el 100% tubo de tórax. La media de días de hospitalización fue de 5 días y la mortalidad fue del 10.4%.- Conclusiones: Se registraron diferencias estadísticamente significativas entre ambas instituciones en las características clínicas en cuanto a la procedencia, intensidad del dolor, frecuencia cardiaca, murmullo vesicular disminuido y presentación de cianosis. Además se evidencia una alta mortalidad.au
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The objective of this dissertation is to explore a more accurate and versatile approach to investigating the neutralization of spores suffered from ultrafast heating and biocide based stresses, and further to explore and understand novel methods to supply ultrafast heating and biocides through nanostructured energetic materials A surface heating method was developed to apply accurate (± 25 ˚C), high heating rate thermal energy (200 - 800 ˚C, ~103 - ~105 ˚C/s). Uniform attachment of bacterial spores was achieved electrophoretically onto fine wires in liquids, which could be quantitatively detached into suspension for spore enumeration. The spore inactivation increased with temperature and heating rate, and fit a sigmoid response. The neutralization mechanisms of peak temperature and heating rate were correlated to the DNA damage at ~104 ˚C/s, and to the coat rupture by ultrafast vapor pressurization inside spores at ~105 ˚C/s. Humidity was found to have a synergistic effect of rapid heating and chlorine gas to neutralization efficiency. The primary neutralization mechanism of Cl2 and rapid heat is proposed to be chlorine reacting with the spore surface. The stress-kill correlation above provides guidance to explore new biocidal thermites, and to probe mechanisms. Results show that nano-Al/K2S2O8 released more gas at a lower temperature and generated a higher maximum pressure than the other nano-Al/oxysalts. Given that this thermite formulation generates the similar amount of SO2 as O2, it can be considered as a potential candidate for use in energetic biocidal applications. The reaction mechanisms of persulfate and other oxysalts containing thermites can be divided into two groups, with the reactive thermites (e.g. Al/K2S2O8) that generate ~10× higher of pressure and ~10× shorter of burn time ignited via a solid-gas Al/O2 reaction, while the less reactive thermites (e.g. Al/K2SO4) following a condensed phase Al/O reaction mechanism. These different ignition mechanisms were further re-evaluated by investigating the roles of free and bound oxygen. A constant critical reaction rate for ignition was found which is independent to ignition temperature, heating rate and free vs. bound oxygen.
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While news stories are an important traditional medium to broadcast and consume news, microblogging has recently emerged as a place where people can dis- cuss, disseminate, collect or report information about news. However, the massive information in the microblogosphere makes it hard for readers to keep up with these real-time updates. This is especially a problem when it comes to breaking news, where people are more eager to know “what is happening”. Therefore, this dis- sertation is intended as an exploratory effort to investigate computational methods to augment human effort when monitoring the development of breaking news on a given topic from a microblog stream by extractively summarizing the updates in a timely manner. More specifically, given an interest in a topic, either entered as a query or presented as an initial news report, a microblog temporal summarization system is proposed to filter microblog posts from a stream with three primary concerns: topical relevance, novelty, and salience. Considering the relatively high arrival rate of microblog streams, a cascade framework consisting of three stages is proposed to progressively reduce quantity of posts. For each step in the cascade, this dissertation studies methods that improve over current baselines. In the relevance filtering stage, query and document expansion techniques are applied to mitigate sparsity and vocabulary mismatch issues. The use of word embedding as a basis for filtering is also explored, using unsupervised and supervised modeling to characterize lexical and semantic similarity. In the novelty filtering stage, several statistical ways of characterizing novelty are investigated and ensemble learning techniques are used to integrate results from these diverse techniques. These results are compared with a baseline clustering approach using both standard and delay-discounted measures. In the salience filtering stage, because of the real-time prediction requirement a method of learning verb phrase usage from past relevant news reports is used in conjunction with some standard measures for characterizing writing quality. Following a Cranfield-like evaluation paradigm, this dissertation includes a se- ries of experiments to evaluate the proposed methods for each step, and for the end- to-end system. New microblog novelty and salience judgments are created, building on existing relevance judgments from the TREC Microblog track. The results point to future research directions at the intersection of social media, computational jour- nalism, information retrieval, automatic summarization, and machine learning.
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We propose a study of the mathematical properties of voice as an audio signal -- This work includes signals in which the channel conditions are not ideal for emotion recognition -- Multiresolution analysis- discrete wavelet transform – was performed through the use of Daubechies Wavelet Family (Db1-Haar, Db6, Db8, Db10) allowing the decomposition of the initial audio signal into sets of coefficients on which a set of features was extracted and analyzed statistically in order to differentiate emotional states -- ANNs proved to be a system that allows an appropriate classification of such states -- This study shows that the extracted features using wavelet decomposition are enough to analyze and extract emotional content in audio signals presenting a high accuracy rate in classification of emotional states without the need to use other kinds of classical frequency-time features -- Accordingly, this paper seeks to characterize mathematically the six basic emotions in humans: boredom, disgust, happiness, anxiety, anger and sadness, also included the neutrality, for a total of seven states to identify
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Communicating at a high data rate through the ocean is challenging. Such communications must be acoustic in order to travel long distances. The underwater acoustic channel has a long delay spread, which makes orthogonal frequency division multiplexing (OFDM) an attractive communication scheme. However, the underwater acoustic channel is highly dynamic, which has the potential to introduce significant inter-carrier interference (ICI). This thesis explores a number of means for mitigating ICI in such communication systems. One method that is explored is directly adapted linear turbo ICI cancellation. This scheme uses linear filters in an iterative structure to cancel the interference. Also explored is on-off keyed (OOK) OFDM, which is a signal designed to avoid ICI.
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Knowledge Exchange examined different routes in achieving the vision of 'having a layer of scholarly and scientific content openly available in the internet'. One of these routes involves exploring new developments in the future of publishing. Work is being undertaken investigating interesting alternative business models which could contribute to the transition to open access. In this light KE has commissioned a study investigating whether submission fees could play a role in a business model for Open Access journals. The general conclusion of the report bearing the title ‘Submission Fees a tool in the transition to open access?', written by Mark Ware, is that there are benefits to publishers in certain cases to switch to a model in which an author pays a fee when submitting an article. Especially journals with a high rejection rate might be interested in combining submission fees with article processing charges in order to make the transition to open access easier. In certain disciplines, notably economic and finance journals and in some areas of the experimental life sciences, submission fees are already common. Overall there seems to be an interest in the model but the risks, particularly those involved in any transition, are seen by the publishers to outweigh the perceived benefits. There is also a problem in that the advantages offered by submission fees are often general benefits that might improve the system but do not provide publishers and authors with direct incentives to change to open access. To support transition funders, institutions and publication funds could make it clear that submission fees would be an allowable cost. At present this is often unclear in their policies. Author acceptance of submission fees is critical to its success. It is an observable fact that authors will accept them in some circumstances. Author acceptance would require further study though. Based on the interviews and the modelling in the study one model in particular is regarded as the most suitable way to meet the current requirements (i.e. to strengthen open access to research publications). In this model authors pay a submission fee plus an Article Processing Fee and the article is subsequently made available in open access. Both fees are set at levels that balance acceptability with the author community with securing a meaningful mix of revenues for the Publisher.
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This paper details a qualitative exploratory study of rural home-based businesses. Little is known about the formation or operation of home-based businesses in rural areas despite their high incidence rate.in-depth cases are presented and, by employing a methodology designed to elicit rich narratives, the stories of eight participants are told. emergent themes include the motivations for and the realities of operating a rural home-based business, the importance of a contextual factors, and the use of technology.
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A micro gas sensor has been developed by our group for the detection of organo-phosphate vapors using an aqueous oxime solution. The analyte diffuses from the high flow rate gas stream through a porous membrane to the low flow rate aqueous phase. It reacts with the oxime PBO (1-Phenyl-1,2,3,-butanetrione 2-oxime) to produce cyanide ions, which are then detected electrochemically from the change in solution potential. Previous work on this oxime based electrochemistry indicated that the optimal buffer pH for the aqueous solution was approximately 10. A basic environment is needed for the oxime anion to form and the detection reaction to take place. At this specific pH, the potential response of the sensor to an analyte (such as acetic anhydride) is maximized. However, sensor response slowly decreases as the aqueous oxime solution ages, by as much as 80% in first 24 hours. The decrease in sensor response is due to cyanide which is produced during the oxime degradation process, as evidenced by the cyanide selective electrode. Solid phase micro-extraction carried out on the oxime solution found several other possible degradation products, including acetic acid, N-hydroxy benzamide, benzoic acid, benzoyl cyanide, 1-Phenyl 1,3-butadione, 2-isonitrosoacetophenone and an imine derived from the oxime. It was concluded that degradation occurred through nucleophilic attack by a hydroxide or oxime anion to produce cyanide, as well as a nitrogen atom rearrangement similar to Beckmann rearrangement. The stability of the oxime in organic solvents is most likely due to the lack of water, and specifically hydroxide ions. The reaction between oxime and organo-phosphate to produce cyanide ions requires hydroxide ions, and therefore pure organic solvents are not compatible with the current micro-sensor electrochemistry. By combining a concentrated organic oxime solution with the basic aqueous buffer just prior to being used in the detection process, oxime degradation can be avoided while preserving the original electrochemical detection scheme. Based on beaker cell experiments with selective cyanide sensitive electrodes, ethanol was chosen as the best organic solvent due to its stabilizing effect on the oxime, minimal interference with the aqueous electrochemistry, and compatibility with the current microsensor material (PMMA). Further studies showed that ethanol had a small effect on micro-sensor performance by reducing the rate of cyanide production and decreasing the overall response time. To avoid incomplete mixing of the aqueous and organic solutions, they were pre-mixed externally at a 10:1 ratio, respectively. To adapt the microsensor design to allow for mixing to take place within the device, a small serpentine channel component was fabricated with the same dimensions and material as the original sensor. This allowed for seamless integration of the microsensor with the serpentine mixing channel. Mixing in the serpentine microchannel takes place via diffusion. Both detector potential response and diffusional mixing improve with increased liquid residence time, and thus decreased liquid flowrate. Micromixer performance was studies at a 10:1 aqueous buffer to organic solution flow rate ratio, for a total rate of 5.5 μL/min. It was found that the sensor response utilizing the integrated micromixer was nearly identical to the response when the solutions were premixed and fed at the same rate.
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Os atuais esquemas de modulação e acesso ao meio, tais como o Wide- Band Code-Division Multiple Access (WCDMA) ou Orthogonal Frequency- Division Multiple Access (OFDMA), que são otimizados para a gestão eficiente do espetro electromagnético e elevada taxa de transmissão, originam sinais de elevado Peak-to-Average Power Ratio (PAPR) e requisitos de linearidade rigorosos. As arquiteturas de amplificação tradicionais, i.e. baseadas no operação em modo de corrente do dispositivo ativo, são incapazes de satisfazer estes requisitos em simultâneo. Assim, o amplificador de potência (do inglês, Power Ampli_er (PA)) incorre numa degradação significativa de rendimento energético em favor de maior linearidade, aumentando simultaneamente os custos de operação das estacões base para os operadores de telecomunicações móveis e o impacte ambiental. Este trabalho foca-se no estudo da arquitetura Doherty, a principal solução encontrada para melhorar o compromisso linearidade/rendimento para aplicações em estações-base de comunicações móveis. Para tal, são expostos os princípios básicos de amplificadores de rádio frequência assim como a análise teórica do tradicional PA Doherty (do inglês, Doherty Power Amplifier (DhPA)) de duas vias e suas variantes. O estudo _e complementado com o projeto e implementação de um PA excitador, em classe-AB, e de um DhPA de elevada potência, colocando-se em prática a teoria e técnicas de projeto estudadas ao longo deste trabalho, aliadas aos desafios da implementação com dispositivos reais de elevada potência.
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As infecções cervicais profundas constituem um verdadeiro desafio clínico, permanecendo na actualidade um problema relevante de saúde. Objectivo: Análise estatística dos internamentos com diagnóstico de celulite/abcesso cervical no Serviço de Otorrinolaringologia do Hospital Prof. Doutor Fernando Fonseca. Material e métodos: Avaliação de processos clínicos referentes a internamentos com o diagnóstico de entrada de celulite/ abcesso cervical, entre 2001-2011. Resultados: Neste período foram internados 80 doentes com média de idade de 44 anos. As infecções odontogénicas foram responsáveis por 83,3% das etiologias detectadas. O tempo médio de internamento foi de 8,72 dias. 94% dos doentes foram medicados com antibioterapia de acção dupla e em 22,5% recorreu-se à drenagem cervical. Conclusão: Ainda hoje as infecções cervicais profundas constituem casos de gravidade acrescida, com índice de mortalidade elevado. A infecção odontogénica constitui a sua principal etiologia. A instituição de antibioterapia endovenosa precoce e eventual drenagem cirúrgica são fundamentais no tratamento desta condição.
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Objectivo: analisar a experiência recente em cirurgia estapédica do Hospital Professor Doutor Fernando Fonseca, recorrendo à avaliação dos seus resultados audiométricos. Materiais e métodos: avaliação retrospectiva de processos clínicos referentes a 155 cirurgias estapédicas consecutivas realizadas no Hospital Professor Doutor Fernando Fonseca, entre Janeiro de 2006 e Dezembro de 2010. Resultados: a média de idades foi de 43,6 anos. A média de 4 frequências (0.5, 1, 2 e 4 kHz) do gap aero-ósseo pós- operatório foi de 5,2 dB. O ganho auditivo médio registado foi de 27 dB sendo a taxa de sucesso cirúrgico de 88,2%. A alteração da condução óssea nas altas frequências foi de 4,9 dB. Conclusões: A cirurgia estapédica apresenta uma elevada taxa de sucesso e baixa frequência de complicações, sendo uma opção preferencial no tratamento da otosclerose. Os resultados deste trabalho confirmam-no reforçando o recurso à cirurgia estapédica no Hospital Professor Doutor Fernando Fonseca.
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BACKGROUND: Reconstruction of the distal femur after resection for malignant bone tumors in skeletally immature children is challenging. The use of megaprostheses has become increasingly popular in this patient group since the introduction of custom-made, expandable devices that do not require surgery for lengthening, such as the Repiphysis(®) Limb Salvage System. Early reports on the device were positive but more recently, a high complication rate and associated bone loss have been reported. QUESTIONS/PURPOSES: We asked: (1) what are the clinical outcomes using the Musculoskeletal Tumor Society (MSTS) scoring system after 5-year minimum followup in patients treated with this prosthesis at one center; (2) what are the problems and complications associated with the lengthening procedures of this implant; and (3) what are the specific concerns associated with revision of this implant? METHODS: At our institute, between 2002 and 2007, the Repiphysis(®) expandable prosthesis was implanted in 15 children (mean age, 8 years; range, 6-11 years) after distal femoral resection for malignant bone tumors. During this time, the general indication for use of this implant was resection of the distal femur for localized malignant bone tumors in pediatric patients. Alternative techniques used for this indication were modular prosthetic reconstruction, massive (osteoarticular or intercalary) allograft reconstruction, or rotationplasty. Age and tumor extension were the main factors to decide on the surgical indication. Of the 15 patients who had this prosthesis implanted during reconstruction surgery, five died with the implant in situ or underwent amputation before 5 years followup and the remaining 10 were evaluated at a minimum of 5 years (mean, 104 months; range, 78-140 months). No patients were lost to followup. These 10 patients were long-term survivors and underwent the lengthening program. They were included in our study analysis. The first seven lengthening procedures were attempted in an outpatient setting; however, owing to pain and burning sensations experienced by the patients, the procedures failed to achieve the desired lengthening. Therefore, other procedures were performed with the patients under general anesthesia. We reviewed clinical data at index surgery for all 15 patients. We further analyzed the lengthening procedures, implant survival, radiographic and functional results, for the 10 long-term survivors. Functional results were assessed according to the MSTS scoring system. Complications were classified according to the International Society of Limb Salvage (ISOLS) classification system. RESULTS: Nine of the 10 survivors underwent revision of the implant for mechanical failure. They had a mean MSTS score of 64% (range, 47%-87%) before revision surgery. At final followup the 10 long-term surviving patients had an average MSTS score of 81% (range, 53%-97%). In total, we obtained an average lengthening of 39 mm per patient (range, 17-67 mm). Exact expansion of the implant was unpredictable and difficult to control. Nine of 10 of the long-term surviving patients underwent revision surgery of the prosthesis-eight for implant breakage and one for stem loosening. At revision surgery, six patients had another type of expandable prosthesis implanted and three had an adult-type megaprosthesis implanted. In five cases, segmental bone grafts were used during revision surgery to compensate for loss of bone stock. CONCLUSIONS: We could not comfortably expand the Repiphysis(®) prosthesis in an outpatient setting because of pain experienced by the patients during the lengthening procedures. Furthermore, use of the prosthesis was associated with frequent failures related to implant breakage and stem loosening. Revisions of these procedures were complex and difficult. We no longer use this prosthesis and caution others against the use of this particular prosthesis design. LEVEL OF EVIDENCE: Level IV, therapeutic study.