997 resultados para Reference parameters


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In order to distinguish dysfunctional gait; clinicians require a measure of reference gait parameters for each population. This study provided normative values for widely used parameters in more than 1400 able-bodied adults over the age of 65. We also measured the foot clearance parameters (i.e., height of the foot above ground during swing phase) that are crucial to understand the complex relationship between gait and falls as well as obstacle negotiation strategies. We used a shoe-worn inertial sensor on each foot and previously validated algorithms to extract the gait parameters during 20 m walking trials in a corridor at a self-selected pace. We investigated the difference of the gait parameters between male and female participants by considering the effect of age and height factors. Besides; we examined the inter-relation of the clearance parameters with the gait speed. The sample size and breadth of gait parameters provided in this study offer a unique reference resource for the researchers.

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BACKGROUND: Knowledge of normal heart weight ranges is important information for pathologists. Comparing the measured heart weight to reference values is one of the key elements used to determine if the heart is pathological, as heart weight increases in many cardiac pathologies. The current reference tables are old and in need of an update. AIMS: The purposes of this study are to establish new reference tables for normal heart weights in the local population and to determine the best predictive factor for normal heart weight. We also aim to provide technical support to calculate the predictive normal heart weight. METHODS: The reference values are based on retrospective analysis of adult Caucasian autopsy cases without any obvious pathology that were collected at the University Centre of Legal Medicine in Lausanne from 2007 to 2011. We selected 288 cases. The mean age was 39.2 years. There were 118 men and 170 women. Regression analyses were performed to assess the relationship of heart weight to body weight, body height, body mass index (BMI) and body surface area (BSA). RESULTS: The heart weight increased along with an increase in all the parameters studied. The mean heart weight was greater in men than in women at a similar body weight. BSA was determined to be the best predictor for normal heart weight. New reference tables for predicted heart weights are presented as a web application that enable the comparison of heart weights observed at autopsy with the reference values. CONCLUSIONS: The reference tables for heart weight and other organs should be systematically updated and adapted for the local population. Web access and smartphone applications for the predicted heart weight represent important investigational tools.

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This work aimed at assessing the doses delivered in Switzerland to paediatric patients during computed tomography (CT) examinations of the brain, chest and abdomen, and at establishing diagnostic reference levels (DRLs) for various age groups. Forms were sent to the ten centres performing CT on children, addressing the demographics, the indication and the scanning parameters: number of series, kilovoltage, tube current, rotation time, reconstruction slice thickness and pitch, volume CT dose index (CTDI(vol)) and dose length product (DLP). Per age group, the proposed DRLs for brain, chest and abdomen are, respectively, in terms of CTDI(vol): 20, 30, 40, 60 mGy; 5, 8, 10, 12 mGy; 7, 9, 13, 16 mGy; and in terms of DLP: 270, 420, 560, 1,000 mGy cm; 110, 200, 220, 460 mGy cm; 130, 300, 380, 500 mGy cm. An optimisation process should be initiated to reduce the spread in dose recorded in this study. A major element of this process should be the use of DRLs.

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Increased renal resistive index (RRI) has been recently associated with target organ damage and cardiovascular or renal outcomes in patients with hypertension and diabetes mellitus. However, reference values in the general population and information on familial aggregation are largely lacking. We determined the distribution of RRI, associated factors, and heritability in a population-based study. Families of European ancestry were randomly selected in 3 Swiss cities. Anthropometric parameters and cardiovascular risk factors were assessed. A renal Doppler ultrasound was performed, and RRI was measured in 3 segmental arteries of both kidneys. We used multilevel linear regression analysis to explore the factors associated with RRI, adjusting for center and family relationships. Sex-specific reference values for RRI were generated according to age. Heritability was estimated by variance components using the ASSOC program (SAGE software). Four hundred women (mean age±SD, 44.9±16.7 years) and 326 men (42.1±16.8 years) with normal renal ultrasound had mean RRI of 0.64±0.05 and 0.62±0.05, respectively (P<0.001). In multivariable analyses, RRI was positively associated with female sex, age, systolic blood pressure, and body mass index. We observed an inverse correlation with diastolic blood pressure and heart rate. Age had a nonlinear association with RRI. We found no independent association of RRI with diabetes mellitus, hypertension treatment, smoking, cholesterol levels, or estimated glomerular filtration rate. The adjusted heritability estimate was 42±8% (P<0.001). In a population-based sample with normal renal ultrasound, RRI normal values depend on sex, age, blood pressure, heart rate, and body mass index. The significant heritability of RRI suggests that genes influence this phenotype.

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Determination of fat-free mass (FFM) and fat mass (FM) is of considerable interest in the evaluation of nutritional status. In recent years, bioelectrical impedance analysis (BIA) has emerged as a simple, reproducible method used for the evaluation of FFM and FM, but the lack of reference values reduces its utility to evaluate nutritional status. The aim of this study was to determine reference values for FFM, FM, and %FM by BIA in a white population of healthy subjects, to observe the changes in these values with age, and to develop percentile distributions for these parameters. Whole-body resistance of 1838 healthy white men and 1555 women, aged 15-64 y, was determined by using four skin electrodes on the right hand and foot. FFM and FM were calculated according to formulas validated for the subject groups and analyzed for age decades. This is the first study to present BIA-determined age- and sex-specific percentiles for FFM, FM, and %FM for healthy subjects, aged 15-64 y. Mean FM and %FM increased progressively in men and after age 45 y in women. The results suggest that any weight gain noted with age is due to a gain in FM. In conclusion, the data presented as percentiles can serve as reference to evaluate the normality of body composition of healthy and ill subject groups at a given age.

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Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E), peak A wave (peak A), E/A ratio (E/A), E wave deceleration time (EDT) and isovolumic relaxation time (IRVT) were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT), by age (peak A and E/A) and by body weight (TRIV). Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.

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Abstract: Magellanic penguins (Spheniscus magellanicus) usually arrive in poor body conditions at Brazilian beaches during the winter. Hematology provides valuable information about clinical and immunity status of the animals. The aims of this study were to determine the hematologic, total plasma protein (TPP) and fibrinogen profiles of young and adult magellanic penguins in PROAMAR and CETAS-SC, relating these results with the state of health and survival possibility of the animals. In Paraná 14 animals were evaluated in pre and eight in post-rehabilitation and 29 animals were evaluated in Santa Catarina after rehabilitation. Before rehabilitation, all animals showed weakness. In hematological exams of these animals, we found that anemia was present in 83% of the penguins that died and 50% of those which survived. The heterophils/lymphocytes (H/L) ratio was 3.87±0.57 in animals that died, significantly higher than the average of 2.20±0.30 for animals that survived. These two parameters are useful to assess the survival possibility of animals to rehabilitation. The body condition score was positively correlated with hematocrit and TPP, and negatively correlated with H/L ratio. After rehabilitation, the values were similar to other animals of the family Spheniscidae, with averages ranging from 1.64 to 1.90x106 erythrocytes/μL; 43.38 to 48.80% of hematocrit; 12.45 to 13.52g/dL of hemoglobin; 8,684 to 14,011 leukocytes/μL; 4,767 to 8,041 heterophils/μL; 3,215 to 4,951 lymphocytes/μL; 95 to 655 eosinophils/μl; 179.8 to 277.9 monocytes/μL; 141 to 184.9 basophils/μL; and 1.26 to 1.74 of H/L ratio. These parameters can therefore be used as reference values and release parameters for young and adult Magellanic penguins in captivity on the rehabilitation centers.

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Waste combustion has gone from being a volume reducing discarding-method to an energy recovery process for unwanted material that cannot be reused or recycled. Different fractions of waste are used as fuel today, such as; municipal solid waste, refuse derived fuel, and solid recovered fuel. Furthermore, industrial waste, normally a mixture between commercial waste and building and demolition waste, is common, either as separate fuels or mixed with, for example, municipal solid waste. Compared to fossil or biomass fuels, waste mixtures are extremely heterogeneous, making it a complicated fuel. Differences in calorific values, ash content, moisture content, and changing levels of elements, such as Cl and alkali metals, are common in waste fuel. Moreover, waste contains much higher levels of troublesome trace elements, such as Zn, which is thought to accelerate a corrosion process. Varying fuel quality can be strenuous on the boiler system and may cause fouling and corrosion of heat exchanger surfaces. This thesis examines waste fuels and waste combustion from different angles, with the objective of giving a better understanding of waste as an important fuel in today’s fuel economy. Several chemical characterisation campaigns of waste fuels over longer time periods (10-12 months) was used to determine the fossil content of Swedish waste fuels, to investigate possible seasonal variations, and to study the presence of Zn in waste. Data from the characterisation campaigns were used for thermodynamic equilibrium calculations to follow trends and determine the effect of changing concentrations of various elements. The thesis also includes a study of the thermal behaviour of Zn and a full—scale study of how the bed temperature affects the volatilisation of alkali metals and Zn from the fuel. As mixed waste fuel contains considerable amounts of fresh biomass, such as wood, food waste, paper etc. it would be wrong to classify it as a fossil fuel. When Sweden introduced waste combustion as a part of the European Union emission trading system in the beginning of 2013 there was a need for combustion plants to find a usable and reliable method to determine the fossil content. Four different methods were studied in full-scale of seven combustion plants; 14Canalysis of solid waste, 14C-analysis of flue gas, sorting analysis followed by calculations, and a patented balance method that is using a software program to calculate the fossil content based on parameters from the plant. The study showed that approximately one third of the coal in Swedish waste mixtures has fossil origins and presented the plants with information about the four different methods and their advantages and disadvantages. Characterisation campaigns also showed that industrial waste contain higher levels of trace elements, such as Zn. The content of Zn in Swedish waste fuels was determined to be approximately 800 mg kg-1 on average, based on 42 samples of solid waste from seven different plants with varying mixtures between municipal solid waste and industrial waste. A review study of the occurrence of Zn in fuels confirmed that the highest amounts of Zn are present in waste fuels rather than in fossil or biomass fuels. In tires, Zn is used as a vulcanizing agent and can reach concentration values of 9600-16800 mg kg-1. Waste Electrical and Electronic Equipment is the second Zn-richest fuel and even though on average Zn content is around 4000 mg kg-1, the values of over 19000 mg kg-1 were also reported. The increased amounts of Zn, 3000-4000 mg kg-1, are also found in municipal solid waste, sludge with over 2000 mg kg-1 on average (some exceptions up to 49000 mg kg-1), and other waste derived fuels (over 1000 mg kg-1). Zn is also found in fossil fuels. In coal, the average level of Zn is 100 mg kg-1, the higher amount of Zn was only reported for oil shale with values between 20-2680 mg kg-1. The content of Zn in biomass is basically determined by its natural occurrence and it is typically 10-100 mg kg-1. The thermal behaviour of Zn is of importance to understand the possible reactions taking place in the boiler. By using thermal analysis three common Zn-compounds were studied (ZnCl2, ZnSO4, and ZnO) and compared to phase diagrams produced with thermodynamic equilibrium calculations. The results of the study suggest that ZnCl2(s/l) cannot exist readily in the boiler due to its volatility at high temperatures and its conversion to ZnO in oxidising conditions. Also, ZnSO4 decomposes around 680°C, while ZnO is relatively stable in the temperature range prevailing in the boiler. Furthermore, by exposing ZnO to HCl in a hot environment (240-330°C) it was shown that chlorination of ZnO with HCl gas is possible. Waste fuel containing high levels of elements known to be corrosive, for example, Na and K in combination with Cl, and also significant amounts of trace elements, such as Zn, are demanding on the whole boiler system. A full-scale study of how the volatilisation of Na, K, and Zn is affected by the bed temperature in a fluidised bed boiler was performed parallel with a lab-scale study with the same conditions. The study showed that the fouling rate on deposit probes were decreased by 20 % when the bed temperature was decreased from 870°C to below 720°C. In addition, the lab-scale experiments clearly indicated that the amount of alkali metals and Zn volatilised depends on the reactor temperature.

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The present work aims at deciphering the processes that control the nutrient distribution along the EEZ (Exclusive Economic Zone of India) of the west coast of India and to bring out its linkage with primary and secondary productivity. This work assume utmost importance as very few studies have hitherto focused entirely on the EEZ of the west coast of India to address the biochemical responses brought about by monsoons. The present study examines the seasonal variations in physicochemical parameters and associated primary biological responses along the west coast of India. This study targets to measure and understand the shelf ocean exchange in a typical coastal upwelling region of the southeast Arabian Sea, and the influence of convective mixing along the northern part of the west coast of India. The study focuses more directly on coastal upwelling along the southwest coast of India, within the EEZ. The effects of coastal upwelling, eddy formation and the offshore advection are apparent in the present investigation. This has consequences to fisheries and climate, in energy transfer to the food chain and the increased sequestering of carbon in the ocean. The study also focuses on the Oxygen Minimum Zone (OMZ) and dentrification observed along the EEZ of the west coast of India on a seasonal scale. In the study, an attempt is also made to demarcate the geographical boundaries of the denitrification zone in the EEZ of India and on the nature and magnitude of these variations, on a seasonal and inter annual scales

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The thesis attempts to study the changes in oceanographic parameters associated with extreme climatic events,the influence of oceanographic as well as meteorological parameters on fishes.The characteristics of major pelagic fishes of southwest coast of India(Oil sardine and Indian mackerel) have been described here.A description on study area and period of study is also described .The impact of extreme climatic events on the oceanographic variability of Eastern Arabian Sea.The extreme climatic event,the Indian Ocean Dipole associated with EI Nino Southern Oscillation is taken into consideration.The variability in oil sardine and mackerel landings of southwest coast of India during the study period.The trend analysis of the landings has been done and also a prediction model is applied for the landings.The influence of environmental parameters on oil sardine as well as mackerel fishery has been explained .With regression analysis ,the significant relation between environmental parameters and fish landings are also been recognized.The prediction of landings is done with these environmental parameters.

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This thesis Entitled macrobenthos of the continental margin (200-1000m) of south eastern arabian sea with special reference to polychaetes. The continental margins are geologically complex and hydrodynamically active regions of the ocean, where vital biogeochemical processes take place from a global perspective. The Eastern Arabian Sea is one of the most productive regions of the world, and as a result, vast amount of organic matter is supplied to the sub surface waters and sea bed of the Arabian Sea. In this study, data on faunal abundance, standing crop and faunal composition, together with sedimentary and environmental parameters were collected from three depths (200m, 500m & 1000m) in nine bathymetric transects along the South Eastern Arabian Sea (from Cape Comorin to Karwar) during three surveys. In the present study, five textural classes of sediments were identified from the SEAS margin, viz. sand, silty sand, sandy silt, clayey silt and admixture of sand, silt and clay. The composition of sand was higher in the southern region and decreased progressively towards the north. On the shelf edge and upper slope regions in the south (Cape to Kollam) in particular, sandy sediments dominated .

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This thesis Entitled studies on the macrobenthic community of cochin backwaters with special reference to culture of eriopisa chilkensis (Gammaridae- amphipoda).Benthic organisms are usually studied for environmental impact assessment, pollution control and resource conservation. The benthic monitoring component has three major objectives: 1) characterize the benthic communities to assess the estuarine health, 2) determine seasonal and spatial variability in benthic communities, and 3) detect changes in the estuarine community through examination of changes in abundances of specific indicator taxa and other standard benthic indices.Cochin backwaters situated at the tip of the northern Vembanad lake is a tropical positive estuarine system. The backwaters of Kerala support as much biological productivity and diversity as tropical rain forest and are responsible for the rich fishery potential of Kerala. Backwaters also act as nursery grounds for commercially important prawns and fishes.The thesis has been subdivided into seven chapters. The first chapter gives a general introduction about the topic and also highlights the scope and purpose of the study. The second chapter covers the methodology adopted for the collection and analysis of water quality parameters, sediment and the macrobenthic fauna.Chapter 3 deals with hydrographic features, sediment characteristics and the spatial variation and abundance of macrobenthic fauna in the Cochin estuary.Chapter 4 explains the impact of organic enrichment on macrobenthic popUlation in the Cochin estuary and includes the comparison of the present data with the earlier work in this region.Chapter 5 deals with seasonal variability in abundance of macrobenthic species in the estuary. The study was conducted from 9 stations during three seasons (pre-monsoon, monsoon and post-monsoon) in 2003.Chapter 6 deals with Life history and Population Dynamics of Eriopisa chilkensis Chilton (Gammaridae-Amphipoda). The life cycle of the gammarid amphipod Eriopisa chilkensis from the Cochin estuary, south west coast of India was studied for the first time under laboratory conditions.

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There are only a few attempts in the Indian ocean to evolve reliable climatic models of energy exchange fluxes and to study their inter annul variations. Large space scale and time history of the flux fields could be estimated by the bulk aerodynamic exchange and radiation equation, making use of the climatic normal’s of the related parameters derived from the remarkably good amount of surface marine observations compiled and made available on magnetic tape TDF II by the national climatic centre of NOAA for the period of years 1854 –early 1973. In this thesis the author has made an attempt to calculate the thermal energy exchange fluxes in a meaningful way, using the bulk aerodynamic coefficients which depend on the changes in the wind speed. The spatial and temporal distribution of the exchanges of energy between the ocean and atmosphere , are presented and their impact on the climatic variations of the Indian ocean are discussed from the point of view of predominating air sea interaction processes.

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Coral Reefs are marine, biogenic, wave resistant carbonate structures, formed of the skeletal remains of hermatypic, or reef building organisms. The main reef builders are calcifying Rhodophytes, molluscs, sponges, polychaetes and Cnidarians. Among them, scleractinian corals and hydrocorallians are by far the most important contributors to the formation of reefs. Coral reefs cover approximately 600 thousand square kilometers of the earth's surface (Crossland fl a_1., 1991) which is about 2x106 square kilometres of tropical oceans.

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Quaternary stratigraphy of the Kerala coast and the genetic aspects of the sediments are discussed. The age of limeshells, and peaty sediments determined by radio carbon dating have been used for reconstruction of sea level changes. Evolution of red sands occurring in some parts of the coastal tract of Kerala is also discussed, based on textural parameters and quartz grain morphology.