180 research outputs found

    Methodology of calculation of construction and hydrodynamic parameters of a foam layer apparatus for mass-transfer processes

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    Промислова реалізація методу стабілізації газорідинного шару дозволяє значно розширити галузь застосування пінних апаратів і відкриває нові можливості інтенсифікації технологічних процесів з одночасним створенням маловідходних технологій. У статті встановлені основні параметри, що впливають на гідродинаміку пінних апаратів, розглянуті основні конструкції та режими роботи пінних апаратів. Виявлено зв'язок гідродинамічних параметрів. Розглянуто гідродинамічні закономірності пінного шару. Вказані фактори, що впливають на процес масообміну, як в газовій, так і в рідкій фазах. Проведений аналіз ряду досліджень показав, що перспективним напрямком інтенсифікації процесу масообміну є розробка апаратів з трифазним псевдозрідженим шаром зрошуваної насадки складних форм із сітчастих матеріалів. Отже, необхідне проведення спеціальних досліджень гідродинамічних режимів роботи апарату з сітчастою насадкою і визначенням параметрів, що впливають на швидкість переходу насадки з одного режиму в інший.Industrial implementation of the stabilization method of the gas-liquid layer can significantly expand the field of use of foaming apparatus and opens up new opportunities for intensifying technological processes with the simultaneous creation of low-waste technologies. The article establishes the basic parameters influencing the hydrodynamics of foam apparatus, considers the basic constructions and operating modes of foam apparatus. The connection of hydrodynamic parameters is revealed. The hydrodynamic laws of the foam layer are considered. The indicated factors affecting the process of mass transfer, both in the gas and in the liquid phases. The conducted analysis of a number of studies showed that the perspective direction of intensification of the mass transfer process is the development of apparatuses with a three-phase fluidized bed of an irrigated nozzle of complex forms with mesh materials

    Ectopic Cushing' syndrome caused by a neuroendocrine carcinoma of the mesentery

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    BACKGROUND: ACTH overproduction within the pituitary gland or ectopically leads to hypercortisolism. Here, we report the first case of Cushing' syndrome caused by an ectopic ACTH-secreting neuroendocrine carcinoma of the mesentery. Moreover, diagnostic procedures and pitfalls associated with ectopic ACTH-secreting tumors are demonstrated and discussed. CASE PRESENTATION: A 41 year-old man presented with clinical features and biochemical tests suggestive of ectopic Cushing's syndrome. First, subtotal thyroidectomy was performed without remission of hypercortisolism, because an octreotide scan showed increased activity in the left thyroid gland and an ultrasound revealed nodules in both thyroid lobes one of which was autonomous. In addition, the patient had a 3 mm hypoenhancing lesion of the neurohypophysis and a 1 cm large adrenal tumor. Surgical removal of the pituitary lesion within the posterior lobe did not improve hypercortisolism and we continued to treat the patient with metyrapone to block cortisol production. At 18-months follow-up from initial presentation, we detected an ACTH-producing neuroendocrine carcinoma of the mesentery by using a combination of octreotide scan, computed tomography scan, and positron emission tomography. Intraoperatively, use of a gamma probe after administration of radiolabeled (111)In-pentetreotide helped identify the mesenteric neuroendocrine tumor. After removal of this carcinoma, the patient improved clinically. Laboratory testing confirmed remission of hypercortisolism. An octreotide scan 7 months after surgery showed normal results. CONCLUSION: This case underscores the diagnostic challenge in identifying an ectopic ACTH-producing tumor and the pluripotency of cells, in this case of mesenteric cells that can start producing and secreting ACTH. It thereby helps elucidate the pathogenesis of neuroendocrine tumors. This case also suggests that patients with ectopic Cushing's syndrome and an octreotide scan positive in atypical locations may benefit from explorative radioguided surgery using (111)In-pentetreotide and a gamma probe

    Challenges and Pitfalls in the Management of Parathyroid Carcinoma: 17-Year Follow-Up of a Case and Review of the Literature

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    A 29-year-old man presented to his primary care physician with nausea, severe weight loss and muscle weakness. He had a hard, fixed neck swelling. He was severely hypercalcaemic with 10-fold increased parathyroid hormone (PTH) concentrations. A diagnosis of primary hyperparathyroidism was established and the patient was referred for parathyroidectomy. At neck exploration, an enlarged parathyroid gland with invasive growth into the thyroid gland was found and removed, lymph nodes were cleared and hemithyroidectomy was performed. A suspected diagnosis of parathyroid carcinoma was confirmed histologically. Serum calcium and PTH levels normalised post-operatively, but hyperparathyroidism recurred within 3 years of surgery. Over the following 17 years, control of hypercalcaemia represented the most difficult challenge despite variable success achieved with repeated surgical interventions, embolisations, radiofrequency ablation of metastases and treatment with calcimimetics, bisphosphonates and haemodialysis using low-dialysate calcium. In this paper, we report the challenges and pitfalls we encountered in the management of our patient over nearly two decades of follow-up and review recent literature on the topic

    O potencial pedagógico da Hora do Conto para o desenvolvimento da Comunicação Oral

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    O presente relatório é produto de um projeto de investigação que pretendeu caracterizar a adequação e dinamização da hora do conto com a finalidade de promover o desenvolvimento da comunicação oral, implementada numa sala de 3/4 anos e a adequação didática de um processo de intervenção educativa de estratégias para a promoção do desenvolvimento da Oralidade (incidindo na dinamização da hora conto) implementado numa turma de 3.º ano do 1.º Ciclo do Ensino Básico. Tendo consciência da desvalorização que é atribuída à temática em análise, acreditamos que os profissionais de educação se tornam responsáveis pelo desenvolvimento e aperfeiçoamento das capacidades de comunicação das crianças/alunos. Neste sentido, consideramos que foi extremamente importante investir neste domínio e nas competências a ele associado, nas vertentes de compreensão e expressão orais. Para atingir os objetivos delineamos, planificamos, construímos, aplicamos e avaliamos em sala de aula, um conjunto de intervenções educativas adotando como estratégia principal a dinamização da hora do conto. Assim sendo, podemos verificar através dos resultados obtidos, que efetivamente, a hora do conto e a utilização de diferentes estratégias para a dinamização da mesma, contribuíram positivamente para o desenvolvimento das competências orais dos intervenientes, potenciando melhorias, a vários níveis, nomeadamente na vertente de compressão e de expressão oral dos dois grupos de aplicação.This report is the product of a research project that aimed to characterize the adequacy and dynamization of the story time with the purpose of promoting the development of oral communication, implemented in a 3/4 year classroom and the didactic adequacy of a process of educational intervention strategies to promote the development of Orality (focusing on the dynamization of the story time) implemented in a 3rd year class of the 1st Cycle of Basic Education. Being aware of the devaluation that is attributed to the theme under analysis, we believe that education professionals become responsible for the development and improvement of communication skills of children/students. In this sense, we believe that it was extremely important to invest in this field and in the skills associated with it, in the areas of understanding and oral expression. In order to achieve the objectives, we delineate, plan, build, apply and evaluate in the classroom, a set of educational interventions adopting as the main strategy the dynamization of the story time. Therefore, we can verify through the results obtained, that effectively, the story time and the use of different strategies for the dynamization of the tale, contributed positively to the development of the oral skills of the participants, enhancing improvements, at various levels, particularly in the compression and oral expression of the two groups of application. Keywords: Oral Communication; Compression and Oral Expression; Story Time; Pre-School; 1st Cycle of Basic Education

    Cardiac Perforation Following Left Ventricular Cineangiocardiography

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    Nonpulsatile exophthalmos in carotid-cavernous sinus fistula.

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    An unusual case of carotid artery-cavernous sinus fistula with pulseless exophthalmos is presented in a two and one-half year old child. Though exophthalmos and increased episcleral venous distention were present, the ophthalmic artery pressure was not significantly altered as determined by ocular pneumoplethysmography. Consequently there was no evidence of hypoxic sequelae which frequently occur with this arteriovenous shunt. The combined use of arteriography and ocular pneumoplethysmography is advocated for determining and characterizing the presence of significant intracranial arteriovenous disease
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