Design of a 60 GHz beam waveguide antenna positioner

A development model antenna positioner mechanism with an integral 60 GHz radio frequency beam waveguide is discussed. The system features a 2-ft diameter carbon-fiber reinforced epoxy antenna reflector and support structure, and a 2-degree-of-freedom elevation over azimuth mechanism providing hemispherical field of view. Emphasis is placed on the constraints imposed on the mechanism by the radio frequency subsystems and how they impacted the mechanical configuration

Factors Promoting Silica Urolithiasis (Urinary Calculi) in Sheep

The following study was conducted to determine the effects of a high calcium to phosphorus ratio and alkali-forming effects of the diet on silica urolithiasis in ruminants

Mercury-Selentium Interrelationships in Layers

Results presented in previous Poultry Field Day reports (A.S. Series 73-18, 74-19) have shown 5 to 10 ppm mercury as methylmercury to lower production and reproductive efficiency of hens. Reports from other stations have indicated the existence of a mercury-selenium interrelationship whereby the toxicity of one is reduced by the presence of elevated dietary levels of the other. The studies reported herein were for the purpose of determining the extent that this inter relationship may serve to reduce the detrimental effects of methylmercury or selenium in layers

Mercury and Selenium Interactions During Growth and Reproduction of Chickens (Progress Report)

Elevated levels of mercury exist in various segments of the environment largely from past industrial and agricultural activities. Bacterial conversion of inorganic mercury to the biologically more important methylmercury promotes accumulation in animal bodies. Concentrations tend to increase as methylmercury is passed up the food chain through aquatic organisms to fish and water fowl and eventually to humans. It is this form of mercury, i.e., methylmercury, that has been implicated in egg shell thinning and lowered reproduction in birds

Interrelationships of Mercury, Selenium and Arsenic in Broiler Diets

In previous reports from the South Dakota Agricultural Experiment Station (A.S. Series 73-18, 74-19 and 75-37), the effects of methylmercury on growth, egg production and egg hatchability were documented for Leghorn-type hens. In these studies, methylmercury at levels up to 10 p.p.m. of the diet had no effect upon growth but reduced egg production, egg quality and hatchability. Selenium was shown to be partially effective in overcoming these detrimental effects of mercury. On the other hand, an arsenic-selenium interaction is known to exist and many of the environmental segments providing mercury also contain elevated levels of arsenic. Studies described below were conducted to determine the toxicity of 10 p.p.m. methylmercury for the more rapidly growing broiler-type chick and to determine the extent that nutritional interrelationships between mercury, selenium and arsenic may alter its toxicity and related tissue distribution patterns

Selenite Versus Seleniferous Wheat In The Mercury-Selenium Interrelationships

An interaction between mercury and selenium that reduces the toxicity of methylmercury in growing chicks and laying hens has been demonstrated in previous work from the South Dakota Agricultural Experiment Station (A.S. Series 78-6 and 79-25). An inorganic form of selenium, sodium selenite, was used in those studies. However, much of the selenium occurring in plants and animals is in an organic form, principally selenomethionine and/or selenocysteine bound to protein moeties. Studies described herein were to compare the effectiveness of- selenium as found in seleniferous wheat with that of sodium selenite in counteracting methylmercury toxicity in growing chicks

Outcomes and prognostic factors in parotid gland malignancies: A 10-year single center experience.

Objectives:To describe a 10-year single center experience with parotid gland malignancies and to determine factors affecting outcomes. Study Design:Retrospective review. Methods:The institutional cancer registry was used to identify patients treated surgically for malignancies of the parotid gland between January 2005 and December 2014. Clinical and pathologic data were collected retrospectively from patient charts and analyzed for their association with overall survival (OS) and disease-free survival (DFS). Results:Two hundred patients were identified. Mean age at surgery was 57.8 years, and mean follow-up time was 52 months. One hundred two patients underwent total parotidectomy, while 77 underwent superficial parotidectomy, and 21 underwent deep lobe resection. Seventy patients (35%) required facial nerve (FN) sacrifice. Acinic cell carcinoma was the most common histologic type (22%), followed by mucoepidermoid carcinoma (21.5%) and adenoid cystic carcinoma (12.5%). Twenty-nine patients (14.5%) experienced recurrences, with mean time to recurrence of 23.6 months (range: 1-82 months). Five- and 10-year OS were 81% and 73%, respectively. Five- and 10-year DFS were 80% and 73%, respectively. In univariate analyses, age > 60, histologic type, positive margins, high grade, T-stage, node positivity, perineural invasion, and FN involvement were predictors of OS and DFS. In the multivariate analysis, histology, positive margins, node positivity, and FN involvement were independent predictors of OS and DFS. Conclusions:Our single-center experience of 200 patients suggests that histology, positive margins, node positivity, and FN involvement are independently associated with outcomes in parotid malignancies. Level of Evidence:4

A cidade do Rio de Janeiro e as chuvas de março/93: (des) organização urbana e inundações

The mountainous arcas of Rio de Janeiro act as water divergent areas, converging to the valley-flats. In the last decades, urban expansion has advanced fastly to still forested upward lands, mainly on the north slope of the Tijuca Massif, where numerous "favelas" are located. Changes in the slopes and valley-flats hydrologic behaviour generate major runoff budgets. So major flows-sediment's and flows-garbage's concentrations into the drained valley-axis, naturally or artificially (channels and pluvial tubulations), spreading inundations on the respectives street of the districts's major density population . The Joana, Maracanã and Comprido basins studied in detail show that the mud-flows and garbage-flows concentrate on the knick slopes and the floods on the valley-axis. These events are aggravated by the cumulated rainstorms due to the inadequacy of the urban pluvial drainage system.Os maciços montanhosos da cidade do Rio de Janeiro funcionam como centros dispersores de águas pluviais, as quais, naturalmente, convergem para os fundos de vales. Nas últimas décadas, a expansão urbana tem avançado rapidamente em direção às áreas mais elevadas da cidade, ainda florestadas, principalmente na vertente norte do Maciço da Tijuca, onde se espraiam numerosas favelas. Mudanças no comportamento hidrológico nas encostas e fundos de vales geraram uma maior produção de escoamento superficial. Em decorrência, uma maior concentração de fluxos de sedimentos e lixos dentro dos eixos de vales drenados, naturalmente ou artificialmente (canais e tubulações pluviais), propagando inundações nas respectivas ruas dos bairros de maior densidade populacional. Um estudo detalhado nas bacias dos rios Joana, Maracanã e Comprido mostra que os fluxos de lama e lixos concentram-se nas zonas de ruptura de declive, e as enchentes nos eixos de vales. Estes eventos são agravados pelas chuvas acumuladas devido a insuficiência do sistema de drenagem pluvial urbano

Nasal mucosal melanosis may act as a harbinger of melanoma: A case report

Background: The progression from a benign pigmented lesion on the skin to cutaneous melanoma is better understood, and it could be presumed that a similar progression occurs with mucosal lesions. However, to our knowledge, there has never been documentation of melanosis transforming into melanoma over time. Objective: To describe a transformation of a mucosal melanosis into melanoma. Methods: A 53-year-old man with diffuse melanosis of the nasal cavity underwent surgical resection. Results: Pathology revealed melanocytic hyperplasia without evidence of melanoma. The patient was serially examined, with excisions for new areas of melanosis. The pathology progressed to severely atypical melanocytic proliferation and melanoma in situ over a 4-year period. Conclusion: Nasal melanosis may be a precancerous lesion and may transform into melanoma. All melanosis should be biopsied with close endoscopic observation. Lesions with dysplasia or atypia should be excised due to potential transformation to melanoma

Economic impact of treatment for surgical site infections in cases of total knee arthroplasty in a tertiary public hospital in Brazil

The aim of this study was to estimate the additional cost of treatment of a group of nosocomial infections in a tertiary public hospital. A retrospective observational cohort study was conducted by means of analyzing the medical records of 34 patients with infection after total knee arthroplasty, diagnosed in 2006 and 2007, who met the criteria for nosocomial infection according to the Centers for Disease Control and Prevention. To estimate the direct costs of treatment for these patients, the following data were gathered: length of hospital stay, laboratory tests, imaging examinations, and surgical procedures performed. Their costs were estimated from the minimum values according to the Brazilian Medical Association. The estimated cost of the antibiotics used was also obtained. The total length of stay in the ward was 976 days, at a cost of US$18,994.63, and, in the intensive care unit, it was 34 days at a cost of US$ 5,031.37. Forty-two debridement procedures were performed, at a cost of US$5,798.06, and 1965 tests (laboratory and imaging) were also performed, at a cost of US$ 15,359.25. US$20,845.01 was spent on antibiotics and US$ 1,735.16 on vacuum assisted closure therapy, microsurgical flaps, implant removal, spacer use, and surgical revision. The total additional cost of these cases of hospital infection in 2006 and 2007 was of US$ 91,843.75. Based on that, we demonstrate that the high cost of treatment for hospital infections emphasizes the importance of taking measures to prevent and control hospital infection