944 resultados para Smithsonian Institution. Bureau of Ethnology
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QUESTIONS UNDER STUDY: With the reduction in breast cancer mortality in recent years the aesthetic outcome after treatment has gained increasing attention. The aim of this study was to assess the outcome quality of our single institution concept of free TRAM flap breast reconstruction with the aim of providing data to assist the patient's decision-making when breast reconstruction is an option. PRINCIPLES/METHODS: Thirty-two consecutive patients receiving immediate (n = 14) or delayed (n = 18) breast reconstruction with free transverse rectus abdominis musculocutaneous (TRAM) flaps were included. The selection of patients was based on their own wish and the availability of abdominal tissue, without excluding patients at risk for wound healing complications. Patient data were assessed prospectively and the aesthetic outcome was rated after the final result had been achieved. RESULTS: Ten patients sustained wound healing complications (4 of 9 smokers, 8 of 16 patients with a BMI over 25 kg/m2), 8 of them requiring revisional surgery. An average of 1.06 corrective procedures were performed per patient. The aesthetic outcome was judged to be good by 20 patients, fair by 5 and poor by 1 patient who sustained severe tissue loss. CONCLUSIONS: Our results revealed that a large measure of satisfaction is achievable from breast reconstruction with free TRAM flaps, in spite of the invasive nature of the procedure and the inclusion of patients at risk for wound healing complications. These data may be used in the decision-making process by patients eligible for breast reconstruction after mastectomy.
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Iron ore is one of the most important ores in the world. Over the past century, most mining of iron ore has been focused on magnetite (Fe3O4). As the name suggests, magnetite is magnetic in nature and is easily separated from gangue (unwanted) minerals through magnetic separation processes. Unfortunately, the magnetite ore bodies are diminishing. Because of this, there has been a recent drive to pursue technology that can economically separate hematite (Fe2O3) from its gangue minerals as hematite is a much more abundant source of iron. Most hematite ore has a very small liberation size that is frequently less than 25μm. Beneficiation of any ore with this fine of a liberation size requires advanced processing methods and is seldom pursued. A single process, known as selective flocculation and dispersion, has been successfully implemented at a plant scale for the beneficiation of fine liberation size hematite ore. Very little is known about this process as it was discovered by the U.S. Bureau of Mines by accident. The process is driven by water chemistry and surface chemistry modifications that enhance the separation of the hematite from its gangue minerals. This dissertation focuses on the role of water chemistry and process reagents in this hematite beneficiation process. It has been shown that certain ions, including calcium and magnesium, play a significant role in the process. These ions have a significant effect on the surface chemistry as reported by zeta potential studies. It was shown that magnesium ions within the process water have a more significant impact on surface chemistry than calcium ions due to steric hindrance effects at the hematite surface. It has also been shown that polyacrylic acid dispersants, if used in the process, can increase product quality (increase iron content, decrease phosphorus content, decrease silica content) substantially. Water, surface and reagent chemistry experiments were performed at a laboratory, pilot, and full plant scale during the course of this work. Many of the conclusions developed in the laboratory and pilot scale were found to be true at the full plant scale as well. These studies are the first published in history to develop theories of water chemistry and surface chemistry interactions at a full plant scale.
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A supply of so-called "copper pitch" ore was received by the Montana Bureau of Mines and Geology in response to a request by them from a resident of Kalispell, who had previously sent a specimen to the Bureau for a mineralogical analysis. Since this material was little known and had apparently received but little study under a reflecting microscope, it was thought that such a study might throw some light on the mineralogical and chemical composition of the material.
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Manganese is commonly known to be a metal of great strategic importance. It is essential in the production of all steels, first as a scavenger to remove oxygen and sulfur, and second as an alloying element in wear-resistant steels.
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The Continental porphyry Cu‐Mo mine, located 2 km east of the famous Berkeley Pit lake of Butte, Montana, contains two small lakes that vary in size depending on mining activity. In contrast to the acidic Berkeley Pit lake, the Continental Pit waters have near-neutral pH and relatively low metal concentrations. The main reason is geological: whereas the Berkeley Pit mined highly‐altered granite rich in pyrite with no neutralizing potential, the Continental Pit is mining weakly‐altered granite with lower pyrite concentrations and up to 1‐2% hydrothermal calcite. The purpose of this study was to gather and interpret information that bears on the chemistry of surface water and groundwater in the active Continental Pit. Pre‐existing chemistry data from sampling of the Continental Pit were compiled from the Montana Bureau of Mines and Geology and Montana Department of Environmental Quality records. In addition, in March of 2013, new water samples were collected from the mine’s main dewatering well, the Sarsfield well, and a nearby acidic seep (Pavilion Seep) and analyzed for trace metals and several stable isotopes, including dD and d18O of water, d13C of dissolved inorganic carbon, and d34S of dissolved sulfate. In December 2013, several soil samples were collected from the shore of the frozen pit lake and surrounding area. The soil samples were analyzed using X‐ray diffraction to determine mineral content. Based on Visual Minteq modeling, water in the Continental Pit lake is near equilibrium with a number of carbonate, sulfate, and molybdate minerals, including calcite, dolomite, rhodochrosite (MnCO3), brochantite (CuSO4·3Cu(OH)2), malachite (Cu2CO3(OH)2), hydrozincite (Zn5(CO3)2(OH)6), gypsum, and powellite (CaMoO4). The fact that these minerals are close to equilibrium suggests that they are present on the weathered mine walls and/or in the sediment of the surface water ponds. X‐Ray Diffraction (XRD) analysis of the pond “beach” sample failed to show any discrete metal‐bearing phases. One of the soil samples collected higher in the mine, near an area of active weathering of chalcocite‐rich ore, contained over 50% chalcanthite (CuSO4·5H2O). This water‐soluble copper salt is easily dissolved in water, and is probably a major source of copper to the pond and underlying groundwater system. However, concentrations of copper in the latter are probably controlled by other, less‐soluble minerals, such as brochantite or malachite. Although the acidity of the Pavilion Seep is high (~ 11 meq/L), the flow is much less than the Sarsfield Well at the current time. Thus, the pH, major and minor element chemistry in the Continental Pit lakes are buffered by calcite and other carbonate minerals. For the Continental Pit waters to become acidic, the influx of acidic seepage (e.g., Pavilion Seep) would need to increase substantially over its present volume.
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In the past the steel industry of the United States has depended almost wholly on imports for its supplies of manganese. Although it is well known that there are enormous deposits of low grade manganese ore in the United States the production of substantial amounts of ferro-grade material from domestic sources presents a field for constructive and practical research.
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The laboratory model is considered in this thesis. Information gained from this investigation has not been transferred to the larger industrial machines. Some of the factors noted concerning the efficiency of the laboratory shaking table are inherent in this small scale model only.
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The object of this research was to produce a workable electrolytic cell for the continuous deposition of manganese from aqueous sulphate solutions and determine the critical factors in its operation.
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The smelting of complex lead ores is a difficult operation, especially when they contain considerable amounts of iron and zinc. When these ores are smelted, all of the zinc, which is valuable and well worth recovering, goes into the slag. With the advent of the flotation processes, and the ability of these processes to concentrate the lead and zinc minerals into separate products, the smelting of complex lead ores was to a great extent simplified.
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IMPORTANCE This study addresses the value of patients' reported symptoms as markers of tumor recurrence after definitive therapy for head and neck squamous cell carcinoma. OBJECTIVE To evaluate the correlation between patients' symptoms and objective findings in the diagnosis of local and/or regional recurrences of head and neck squamous cell carcinomas in the first 2 years of follow-up. DESIGN Retrospective single-institution study of a prospectively collected database. SETTING Regional hospital. PARTICIPANTS We reviewed the clinical records of patients treated for oral cavity, oropharyngeal, laryngeal, and hypopharyngeal carcinomas between January 1, 2008, and December 31, 2009, with a minimum follow-up of 2 years. MAIN OUTCOMES AND MEASURES Correlation between symptoms and oncologic status (recurrence vs remission) in the posttreatment period. RESULTS Of the 101 patients included, 30 had recurrences. Pain, odynophagia, and dysphonia were independently correlated with recurrence (odds ratios, 16.07, 11.20, and 5.90, respectively; P < .001). New-onset symptoms had the best correlation with recurrences. Correlation was better between 6 to 12 and 18 to 21 months after therapy and in patients initially treated unimodally (P < .05). Primary stage and tumor site had no effect. CONCLUSIONS AND RELEVANCE The correlation between symptoms and oncologic status is low during substantial periods within the first 2 years of follow-up. New-onset symptoms, especially pain, odynophagia, or dysphonia, better correlate with tumor recurrence, especially in patients treated unimodally.
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In the Burgdorf Museum of Ethnology, a mummy rests in a coffin. According to the inventory book, it was purchased from the Cairo Egyptian museum in 1926. The coffin was now examined by Egyptologists and the mummy was radiocarbon dated and examined by Anthropologists. The aim of the study was to compare the results and to check whether mummy and coffin actually belong together. The skull was examined morphological-anthropologically and by CT as a “blank sample”. Coffin and skull imply that the individual was female. The coffin dates to the Ptolemaic period. Only skull bones are preserved, the ethmoid is damaged. CT images Show resinous substances, bone fragments and brain remnants inside the skull. The ethmoid bone was probably foraminated during the mummification process and thus ended up inside the skull. The individual was mummified between the New Kingdom and the Ptolemaic period. Due to its style, it is most probable that the coffin comes from the Gamhud necropolis. The Burgdorf museum of ethnology inventory book chronicles were largely falsified by the examinations. There is a time gap between coffin and the mummy, there are two possible interpretations: the body was mummified with older linen, or the mummy and the coffin do not belong together. The authors strongly advise further investigations.
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The impact of cancer on the population of Salvador-Bahia, Brazil was studied using mortality data available from the Brazilian National Bureau of Vital Statistics. Average annual site, age, and gender specific and adjusted cancer mortality rates were determined for the years 1977-83 and contrasted with United States cancer mortality rates for the year of 1977. The accuracy of the cancer mortality rates generated by this research was determined by comparing the underlying causes of death as coded on death certificates to pathology reports and to hospital diagnosis of a sample of 966 deaths occurring in Salvador during the year of 1983. To further explore the information available on the death certificate, a population based decedent case control study was used to determine the relationship between type of occupation (proxy for exposure) and mortality by cancer sites known to be occupationally related.^ The rates in Salvador for cancer of the stomach, oral cavity, and biliary passages are, on average, two fold higher than the U.S. rates.^ The death certificate was found to be accurate for 65 percent of the 485 cancer deaths studied. Thirty five histologically confirmed cancer deaths were found in a random sample of 481 deaths from other causes. This means that, approximately 700 more deaths may be lost among the remainder 10,073 death certificates stating a cause other than cancer.^ In addition, despite the known limitations of decedent case-control studies, cancers of the oral cavity OR = 2.44, CI = 1.17-5.09, stomach OR = 2.31, CI = 1.18-4.52, liver OR = 4.06, CI = 1.27-12.99, bladder OR = 6.77, CI = 1.5-30.67, and lymphoma OR = 2.55, CI = 1.04-6.25 had elevated point estimates, for different age strata indicating an association between these cancers and occupations that led to exposure to petroleum and its derivates. ^
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A cross-sectional study on the use of three pesticides and their presence in drinking water sources was conducted in Githunguri/Kiaria community between January 1994-March 1995. The main objective of the study was to determine the extent to which some of the pesticides used by the Githunguri/Kiaria agricultural community were polluting their drinking water sources. Due to monetary and physical limitations, only DDT, its isomers and metabolites, carbofuran and carbaryl pesticides were identified and used as surrogates of pollution for the other pesticides.^ The study area was divided into high and low lying geographic surface areas. Thirty-four and 38 water sampling sites were randomly selected respectively. During wet and dry seasons, a total of 144 water samples were collected and analyzed at the Kenya Bureau of Standards Laboratory in Nairobi. Gas chromatography was used to analyze samples for possible presence of DDT, its isomers and metabolites, while high pressure liquid chromatography was used to analyze samples for carbofuran and carbaryl pesticides.^ Six sites testing positively for DDT, its isomers and metabolites represented 19.4% of the total sampled sites, with a mean concentration of 0.00310 ppb in the dry season and 0.0130 ppb in the wet season. All the six sites testing positively for the same pesticide exceeded the European maximum contaminant limit (MCL) in the wet season, and only one site exceeded the European MCL in the dry season.^ Those sites testing positively for carbofuran and carbaryl represented 5.6% of the total sampled sites. The mean concentration for the carbofuran at the sites was 2.500 ppb and 1.590 ppb in the dry and wet seasons respectively. Similarly, the mean concentration for carbaryl at the sites was 0.281 ppb in the dry season and 0.326 ppb in the wet season.^ One site testing positively for carbofuran exceeded the European MCL and WHO set limit in the wet season, while one site testing positively for the same pesticide exceeded the USA, Canada, European and WHO MCLs in the dry season. Similarly, one site which tested positively for carbaryl pesticide exceeded the European MCL in both seasons.^ Out of the 2,587 community members in the study area, 333 (13%) were exposed through their drinking water sources to the three pesticides investigated by this study. As a public health measure, integrated pest management approaches (IPM), protection of the wells and education of the community is necessary to minimize the pollution of the environment and safeguard the drinking water sources from pollution by the pesticides. ^