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Estudo da qualidade do sedimento através de teste de toxicidade e marcadores de esgoto na Enseada de Ubatuba-SP, Brasil. Influência do aumento da população de veraneio / Study of sediment quality through toxicity tests and sewage markers at Ybatuba Small Bay-SP, Brazil, influenced by increasing population in summer holidaysLuis Fabiano Joaquim de Oliveira 09 October 2009 (has links)
Este estudo teve como objetivo avaliar a toxicidade do sedimento da Enseada de Ubatuba através de testes de toxicidade, utilizando-se fase aquosa e sedimento total antes e depois do aumento da população de veraneio e a contaminação por esgoto urbano. Realizaram-se testes de toxicidade com a água intersticial e interface água/sedimento e larvas de L. variegatus. No testes com sedimento total utilizou-se anfípodo T. viscana. Utilizaram-se as análises de esteróis fecais para verificar a contaminação por esgoto. Foram coletadas em 17 estações. Uma estação do canto direito da Praia do Itaguá foi a única que obteve toxicidade nos três testes na campanha após o aumento da população de veraneio. Para os testes com a fase aquosa, uma estação próxima ao Instituto de Pesca e duas na Praia do Perequê-Açú foram tóxicas nas duas campanhas. Apresentaram contaminação por esgoto e toxicidade para os testes de fase aquosa três estações do canto direito da Praia do Itaguá, uma próxima ao Rio Acaraú, outra em frente ao Rio Grande e também uma na Praia do Perequê-Açú. Uma estação próxima a saída do Rio Grande apresentou indício de contaminação por esgoto, mas não obteve toxicidade na fase aquosa. O aumento da população de veraneio mostrou uma maior toxicidade para os testes com a fase aquosa e uma diminuição do número de sobreviventes de anfípodos. A Enseada de Ubatuba apresentou toxicidade nos testes com fase aquosa em quase todas as estações após o aumento da população, assim deve ser monitorada com freqüência e melhorar a infra-estrutura de saneamento. / The goal of this study was to evaluate the toxicity of the sediment in Ubatuba small Bay through toxicity tests using liquid phase and the total sediment before and after the increase of the floating population and the sewage contamination. The liquid phase was evaluated through toxicity test with interstitial water and water/sediment interface, both with embryos of L. variegatus. The tests with total sediment were utilized amphipod T. viscana. The analyses with chemical faecal steroids marks was utilized for the sewage contamination in the sediment. It was realized samples in 17 stations. One station localized in the right corner of Itaguá beach, was the only one that showed toxicity in the three of the tests in the campaign after the increase of the floating population, two tests with de liquid phase in one station, localized near to Pesca Institute, two stations, localized in the Perequê-Açu beach, was toxic in both campaigns. Contamination by urban sewage and toxicity tests of liquid phase was observed in three stations localized in the right corner of Itaguá beach, other near the mouth of the Acaraú river, and another in front of Grande river and as well one station in the Perequê-Açu beach. One station near the mouth of Grande river had showed indication of contamination by urban sewage, but the liquid phase showed no sign of toxicity. The increase of the floating population showed a high toxicity for the test with liquid phase and a decrease in the number of survives in the amphipods tests. The small bay of Ubatuba showed toxicity in the liquid phase tests in almost of all stations after the increase in the floating population, then the region must be monitored with frequency and it is necessary to improve the structure of the sanitation in the area.
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Microbiological Quality of Toroi: A Māori food delicacyDixon, Lorraine Louise January 2007 (has links)
A study was undertaken to determine the food safety of the fermented Māori delicacy, Toroi. Ten batches of Toroi were prepared by a commonly used traditional method that consisted of boiling the vegetable component, either watercress or puha, and combining it with chopped mussel flesh. The mixture was cooled and then stored in a refrigerator for up to eight months to allow natural fermentation to take place. All ingredients were sourced from retail outlets. The Toroi was examined at intervals over eight months for a range of pathogens (seven in all) that have been related to incidents of food poisoning in ready-to-eat foods in New Zealand. The survival of a faecal contamination indicator, the laboratory grown strain Escherichia coli NZRM 916, was mapped over eight months. Two strategies to prevent the growth of Listeria monocytogenes in Toroi were also investigated. Only one of the seven pathogens sought was recovered from any sample. This pathogen was Bacillus cereus, a spore-former known to be associated with vegetables. All batches contained B. cereus on the day of preparation but after two weeks refrigerated storage there was no further recovery from any sample. There was a very low incidence of natural E. coli in the Toroi, consistent with levels permitted in mussels sold in retail outlets. The laboratory grown strain, E. coli declined substantially over two months and was not recovered from any samples at eight months. A laboratory grown strain of Listeria monocytogenes, (L70) was added to Toroi and grew well with an increase in concentration of about seven-fold, over 19 days storage in a refrigerator. A bacteriocin producing lactic acid bacterium, Lactobacillus sake Lb706, was added in combined culture with L. monocytogenes to Toroi. It was found that at least 5 x108 L. sake cells were required as an inoculum to ensure elimination of L. monocytogenes from the Toroi. When a purified bacteriocin; nisin, was added, a concentration of 10 mg g-1 in the Toroi was required to eliminate L. monocytogenes. The inhibition study results suggest that unacceptably high inocula or purified bacteriocin would be required to prevent the growth of L. monocytogenes in Toroi. The results of this suggest that Toroi be prepared from mussels either purchased from a retail outlet or harvested from sites known to be free from contamination. Toroi should be safe to eat if prepared carefully, chilled promptly and thoroughly and allowed to ferment for at least two weeks. In addition, care should be taken to maintain Toroi at refrigerated temperatures until it is eaten.
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Behavioural Endocrinology of Breeding Adelie Penguins (Pygoscelis adeliae)Ninnes, Calum Edward January 2008 (has links)
Measuring hormonal changes is vital for understanding how the social and physical environment influences behaviour, reproduction and survival. Various methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross validated to ensure they correlate. I directly compare faecal and plasma hormone measurements (Chapter 2), and use the most suitable endocrine measure to test the Darling hypothesis (Chapter 3) - that breeding is hastened and synchronized in larger colonies due to increased social stimulation (mediated by the endocrine system). Blood and faecal samples were simultaneously collected from individual Adelie penguins (Pygoscelis adeliae) for comparison, and assayed for testosterone and corticosterone (or their metabolites). Sex differences and variability within each measure, and correlation of values across measures were compared. For both hormones, plasma samples showed greater variation than faecal samples. Males had higher corticosterone levels than females, but the difference was only significant in faecal samples. Plasma testosterone, but not faecal testosterone, was significantly higher in males than females. Correlation between sample types was poor overall, and weaker in females than in males; perhaps because measures from plasma represent hormones that are both free and bound to globulins, whereas measures from faeces represent only the free portion. Faecal samples also represent a cumulative measure of hormones over time, as opposed to a plasma 'snapshot' concentration. Faecal sampling appears more suitable for assessing baseline hormone levels. In the second study I examined, over two seasons, whether the timing of breeding varied with colony size; larger colonies present occupants with higher levels of social stimulation and are predicted to show earlier, more synchronous breeding. Baseline faecal hormone levels throughout the breeding season, and survival, were measured to investigate possible proximate and ultimate mechanisms for the results. The influence of environmental variability was examined, by relating the timing of breeding, survival, and endocrine changes to sea ice conditions. Colony size did not influence the timing or synchrony of breeding, survival, or hormone levels within years; perhaps because colonies in an Adelie rookery are not independent from the 'social environment' of adjacent colonies. Across years, synchrony in the smaller rookery was higher than in the larger rookery. The scale of these comparisons may exceed the applicability of the Darling hypothesis. Therefore, no support was found for the Darling hypothesis, at the colony or rookery level, in this species. Higher corticosterone metabolite and lower sex hormone levels in the first season correlated to later breeding and lower survival compared to the second season. This is likely due to the persistence of extensive sea ice conditions late into the first season. Researchers should take care in selecting the most appropriate method of hormone measurement for their question. Future studies testing the Darling hypothesis must carefully select their definition of a colony (i.e. a truly isolated social unit) and the scale at which the hypothesis is tested. Combining endocrine measurements with behavioural, survival, and environmental information allows for a more comprehensive interpretation of animal ecology.
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A microsimulation study of the benefits and costs of screening for colorectal cancerStevenson, Christopher Eric, Chris.Stevenson@aihw.gov.au January 2001 (has links)
This thesis examines the benefits and costs of screening for colorectal cancer in the context of an organised population screening programme. It uses microsimulation modelling to derive an optimally cost-effective screening protocol for various combinations of the available screening tests. ¶
First a mathematical model for the natural history of colorectal cancer is derived, based on analyses of Australian population and hospital-based cancer registries combined with data from published studies. Then a model for population based screening is derived based mainly on data from published screening studies, including the four major published randomised controlled trials of faecal occult blood test (FOBT) screening. These two models are used to simulate the application of a screening programme to the Australian population. The simulations are applied to a period of 40 years following 1990 (the studys base year), with both costs and benefits discounted back to the base year at an annual rate of 3%.¶
The models are applied to simulating a population screening programme based on FOBT with a colonoscopy follow up of positive tests. This simulation suggests that the optimal application of such a programme would be to offer annual screening to people aged 50 to 84 years. Such a programme would lead to a cumulative fall in years of life lost to colorectal cancer (YLL) of 28.5% at a cost per year of life saved (YLS) of $8,987. These costs and benefits are consistent with those arising from other currently funded health interventions. They are also consistent with the cost per YLS which Australian governments appear willing to pay for health interventions when justified on the basis of cost-effectiveness. The fall in colorectal cancer deaths from this screening programme should be first detectable by a national monitoring system after around three years of screening. However the full benefits from screening would not be realised before around 30 years of screening.¶
These simulations are based on the standard guaiac FOBT, but the results suggest that significant cost-effective gains could be made by using the newer immunochemical FOBT. Further cost-effect gains could be made by offering sigmoidoscopy every five years in addition to annual FOBT.¶
The models are then applied to simulating population screening programmes using colonoscopy and sigmoidoscopy as primary screening tools. Offering colonoscopy every ten years to all people aged from 45 to 85 leads to an overall fall in cumulative YLL of 37.6%, at a cost of $15,585 per YLS. Offering sigmoidoscopy every three years to all people aged 40 to 85 leads to an overall fall in cumulative YLL of 29.1%, at a cost of $4,862 per YLS. Both of these cost and benefit results are also consistent with the cost per YLS which Australian governments appear willing to pay. The fall in deaths with colonoscopy screening would also be detectable after three years of screening but the fall with sigmoidoscopy screening would not be detectable until after six years of screening. Sigmoidoscopy would need around 35 years of screening to reach its potential gains while colonoscopy screening would not reach its full potential during the 40 year screening period.¶
Finally the models are applied to targeting people at higher risk of cancer. The results show that offering colonoscopy every five years to people at higher risk because of a family history of colorectal cancer is a cost-effective addition to the annual FOBT screening programme.¶
An earlier version of chapter two of this thesis has been published as
Stevenson CE 1995. Statistical models for cancer screening. Statistical Methods in Medical Research; 4: 1923.¶
An expanded version of chapter two, along with parts of chapter one, has been published as
Stevenson CE 1998. Models of screening. In: Encyclopedia of Biostatistics. Armitage P, Colton T, eds. John Wiley and Sons Ltd, pp 39994022.
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Haemorrhoids : Aspects of Symptoms and Results after SurgeryJóhannsson, Helgi Örn January 2005 (has links)
<p>One hundred haemorrhoid patients were compared with 300 matched control persons. Haemorrhoid symptoms and bowel symptoms were studied. Most common symptom of the patients was bleeding (44%), followed by prolapse (24%), hygiene problem (14%), pain (12%) and itching (5%). Bowel symptoms, as bloating and evacuation difficulties, possibly related to IBS, were frequent among the patients.</p><p>556 patients were operated upon with Milligan-Morgan haemorrhoidectomy. 418 (81%) answered a questionnaire on results, and on disturbances in anal continence. Totally140 (33%) reported recurrence, and 139 (33%) patients reported anal incontinence. Forty of the 139 patients associated this to the surgical procedure. Female gender was associated to increased risk of incontinence.</p><p>The 40 patients who reported incontinence, were invited to undergo ano-rectal manometry, saline infusion test, endo-anal ultrasound, proctoscopy and clinical examination. Altogether 19 patients approved to participate. Matched control subjects and 15 persons previously operated for haemorrhoids, but without symptoms of incontinence, served as two reference groups. Incontinence score and saline infusion test showed significantly poorer continence in the patient group. Endo-anal ultrasound showed injury to the external sphincter in 20% of the patients. Anal pressure was slightly lower in the patient group, but the difference was not significant. </p><p>Totally 225 patients were randomised to Milligan-Morgan or Ferguson haemorrhoidectomy. Primary aim was to study changes in anal continence. Other aims were to study postoperative pain, wound healing, complications, patient satisfaction and recurrence and changes in bowel function. Patients in the Ferguson group reported, slightly quicker wound healing (P=0.06). Postoperative pain was equal, as was rate of complications. After one year the Ferguson group reported lower incontinence score, and more satisfied patients. Recurrence rate was equal, 15-17%. Most bowel symptoms were reduced one year after surgery.</p><p>In conclusion, functional bowel symptoms are common in haemorrhoid patients. Haemorrhoidectomy is associated with risk for incontinence in 5-10% of patients and females are at greater risk. A proportion of the patients who claim postoperative incontinence have physiological signs of sphincter incompetence, and external sphincter injuries are observed in those patients. Ferguson haemorrhoidectomy results in better anal continence and more satisfied patients. </p>
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Tracking an elusive predator: Studying the Scandinavian lynx population by use of genetic markersBerlin, Ingrid January 2007 (has links)
<p>Abstract</p><p>Gaining accurate population information is crucial for the conservation and management of species. The National Monitoring Program for Large Carnivores monitors the Swedish lynx population (species Lynx lynx) by surveying family groups, non-invasive sampling and genetic analysis. Ten microsatellite regions were used as genetic markers to retrieve unique individual genotypes, through polymerase chain reactions (PCR) with specific primer-pairs and capillary-electrophoresis. Complete genotypes were matched using an internal database. The aim of this degree project was to show how monitoring of lynx through genetic analysis is carried out at the Department of Evolutionary Biology at Uppsala University, and to evaluate how effective these methods are and how they might be improved.</p><p>Even though most of the methods used were fairly robust and reproducible, non-invasive sampling and microsatellite analysis posed some problems regarding DNA quality and quantity, and increased the risks of certain genotyping errors. These risks might be worth taking though, as genetic analysis, in combination with field observations, gives a more comprehensive picture of the Swedish lynx population.</p>
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Haemorrhoids : Aspects of Symptoms and Results after SurgeryJóhannsson, Helgi Örn January 2005 (has links)
One hundred haemorrhoid patients were compared with 300 matched control persons. Haemorrhoid symptoms and bowel symptoms were studied. Most common symptom of the patients was bleeding (44%), followed by prolapse (24%), hygiene problem (14%), pain (12%) and itching (5%). Bowel symptoms, as bloating and evacuation difficulties, possibly related to IBS, were frequent among the patients. 556 patients were operated upon with Milligan-Morgan haemorrhoidectomy. 418 (81%) answered a questionnaire on results, and on disturbances in anal continence. Totally140 (33%) reported recurrence, and 139 (33%) patients reported anal incontinence. Forty of the 139 patients associated this to the surgical procedure. Female gender was associated to increased risk of incontinence. The 40 patients who reported incontinence, were invited to undergo ano-rectal manometry, saline infusion test, endo-anal ultrasound, proctoscopy and clinical examination. Altogether 19 patients approved to participate. Matched control subjects and 15 persons previously operated for haemorrhoids, but without symptoms of incontinence, served as two reference groups. Incontinence score and saline infusion test showed significantly poorer continence in the patient group. Endo-anal ultrasound showed injury to the external sphincter in 20% of the patients. Anal pressure was slightly lower in the patient group, but the difference was not significant. Totally 225 patients were randomised to Milligan-Morgan or Ferguson haemorrhoidectomy. Primary aim was to study changes in anal continence. Other aims were to study postoperative pain, wound healing, complications, patient satisfaction and recurrence and changes in bowel function. Patients in the Ferguson group reported, slightly quicker wound healing (P=0.06). Postoperative pain was equal, as was rate of complications. After one year the Ferguson group reported lower incontinence score, and more satisfied patients. Recurrence rate was equal, 15-17%. Most bowel symptoms were reduced one year after surgery. In conclusion, functional bowel symptoms are common in haemorrhoid patients. Haemorrhoidectomy is associated with risk for incontinence in 5-10% of patients and females are at greater risk. A proportion of the patients who claim postoperative incontinence have physiological signs of sphincter incompetence, and external sphincter injuries are observed in those patients. Ferguson haemorrhoidectomy results in better anal continence and more satisfied patients.
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Tracking an elusive predator: Studying the Scandinavian lynx population by use of genetic markersBerlin, Ingrid January 2007 (has links)
Abstract Gaining accurate population information is crucial for the conservation and management of species. The National Monitoring Program for Large Carnivores monitors the Swedish lynx population (species Lynx lynx) by surveying family groups, non-invasive sampling and genetic analysis. Ten microsatellite regions were used as genetic markers to retrieve unique individual genotypes, through polymerase chain reactions (PCR) with specific primer-pairs and capillary-electrophoresis. Complete genotypes were matched using an internal database. The aim of this degree project was to show how monitoring of lynx through genetic analysis is carried out at the Department of Evolutionary Biology at Uppsala University, and to evaluate how effective these methods are and how they might be improved. Even though most of the methods used were fairly robust and reproducible, non-invasive sampling and microsatellite analysis posed some problems regarding DNA quality and quantity, and increased the risks of certain genotyping errors. These risks might be worth taking though, as genetic analysis, in combination with field observations, gives a more comprehensive picture of the Swedish lynx population.
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Understanding the relationships between pregnancy, childbirth and incontinencePrendergast, Susan Unknown Date
No description available.
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Understanding the relationships between pregnancy, childbirth and incontinencePrendergast, Susan 11 1900 (has links)
The purpose of this thesis was to explore the relationships between pregnancy, childbirth and incontinence (both urinary and faecal) and the effect of preventive activities during pregnancy on continence. Two papers comprise this thesis. The first paper, a scoping review, focused on examination of how pregnancy and childbirth affect continence in nulliparous women. Several key considerations were identified from the published literature that we suggest are crucial to understanding these relationships. The second paper, a systematic review, is focused on the effect of preventive measures during pregnancy on continence. Pelvic floor muscle training was found to be effective in reducing the incidence of incontinence at 3 months postpartum. Few studies met our inclusion criteria thus limiting analysis of data. Based on these two papers, further prospective research is suggested. The final chapter of this thesis outlines a developing PhD project that addresses gaps identified through the scoping and systematic reviews.
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