901 resultados para distribution transformer life time
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The photopolymerization of methyl,ethyl,butyl, and hexyl methacrylates in solution was studied. The effect of initial initiator and monomer concentrations on the time evolution of polymer concentration (M) over bar (n) and PDI was examined. The reversible chain addition and beta-scission, and primary radical termination steps were included in the mechanism along with the classical steps. The rate equations were derived using continuous distribution kinetics and solved numerically to fit the experimental data. The regressed rate coefficients compared well with the literature data. The model predicted the instantaneous increase in (M) over bar (n) and PDI to steady state values. The rate coefficients exhibited a linear increase with the size of alkyl chain of the alkyl methacrylates.
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Thirty percent of 70-year-old women have osteoporosis; after age of 80 its prevalence is up to 70%. Postmenopausal women with osteoporosis seem to be at an increased risk for cardiovascular events, and deterioration of oral health, as shown by attachment loss of teeth, which is proportional to the severity of osteoporosis. Osteoporosis can be treated with many different medication, e.g. estrogen and alendronate. We randomized 90 elderly osteoporotic women (65-80 years of age) to receive hormone therapy (HT)(2mg E2+NETA), 10mg alendronate, and their combination for two years and compared their effects on bone mineral density (BMD) and turnover, two surrogate markers of the risk of cardiovascular diseases, C-reactive protein (CRP) and E-selectin, as well as oral health. The effect of HT on health-related quality of life (HRQoL) was studied in the population-based cohort of 1663 postmenopausal women (mean age 68 yr) (585 estrogen users and 1078 non-users). BMD was measured with dual-energy X-ray absorptiometry (DXA) at 0, 12 and 24 months. Urinary N-telopeptide (NTX) of type I collagen, a marker of bone resorption, and serum aminoterminal propeptide of human type I procollagen (PINP), a marker of bone formation, were measured every six months of treatment. Serum CRP and E-selectin, were measured at 0, 6, and 12 months. Dental, and periodontal conditions, and gingival crevicular fluid (GCF) matrix metalloproteinase (MMP)-8 levels were studied to evaluate the oral health status and for the mouth symptoms a structured questionnaire was used. The HRQoL was measured with 15D questionnaire. Lumbar spine BMD increased similarly in all treatment groups (6.8-8.4% and 9.1-11.2%). Only HT increased femoral neck BMD at both 12 (4.9%) and 24 months (5.8%), at the latter time point the HT group differed significantly from the other groups. HT reduced bone marker levels of NTX and PINP significantly less than other two groups.Oral HT significantly increased serum CRP level by 76.5% at 6 and by 47.1% (NS) at 12 months, and decreased serum E-selectin level by 24.3% and 30.0%. Alendronate had no effect on these surrogate markers. Alendronate caused a decrease in the resting salivary flow rate and tended to increase GCF MMP-8 levels. Otherwise, there was no effect on the parameters of oral health. HT improved the HRQoL of elderly women significantly on the dimensions of usual activities, vitality and sexual activity, but the overall improvement in HRQoL was neither statistically significant nor clinically important. In conclusion, bisphosphonates might be the first option to start the treatment of postmenopausal osteoporosis in the old age.
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Prevention of cardiovascular diseases is known to postpone death, but in an aging society it is important to ensure that those who live longer are neither disabled nor suffering an inferior quality of life. It is essential both from the point of view of the aging individual as well as that of society that any individual should enjoy a good physical, mental and social quality of life during these additional years. The studies presented in this thesis investigated the impact of modifiable risk factors, all of which affect cardiovascular health in the long term, on mortality and health-related quality of life (HRQoL). The data is based on the all male cohort of the Helsinki Businessmen Study. This cohort, originally of 3.490 men born between 1919 and 1934 has been followed since the 1960s. The socioeconomic status of the participants is similar, since all the men were working in leading positions. Extensive baseline examinations were conducted among 2.375 of the men in 1974 when their mean age was 48 and at this time the health, medication and cardiovascular risk factors of the participants were observed. In 2000, at the mean age of 73, the HRQoL of the survivors of the original cohort was examined using the RAND-36 mailed questionnaire (n=1.864). RAND-36, along with the equivalent SF-36, is the world s most widely used means of assessing generic health. The response rate was generally over 90%. Mortality was retrieved from national registers in 2000 and 2002. For the six substudies of this thesis, the impact of four different modifiable cardiovascular risk factors (weight gain, cholesterol, alcohol and smoking) on the HRQoL in old age was studied both independently and in combination. The follow-up time for these studies varies from 26 up to 39 years. Mortality is reported separately or included in the RAND-36 scores for HRQoL. Elevated levels of all the risk factors examined among the participants in midlife led to a diminished life expectancy. Among survivors, lower weight gain in midlife was associated with better HRQoL, both physically and mentally. Higher levels of serum cholesterol in middle age indicated both an earlier mortality and a decline in the physical component of HRQoL in a dose-response manner during the 39-year follow-up. Mortality was significantly higher in the highest baseline category of reported mean alcohol consumption (≥ 5 drinks/day), but fairly comparable in abstainers and moderate drinkers during the 29-year follow-up. When HRQoL in old age was accounted for mortality, the men with the highest alcohol consumption in midlife clearly had poorer physical and mental health in old age, but the HRQoL of abstainers and those who drank alcohol in moderation were comparatively similar. The amount of cigarette smoking in midlife was shown to have had a dose-response effect on both mortality and HRQoL in old age during the 26 year follow-up. The men smoking over 20 cigarettes daily in middle age lost about 10 years of their life-expectancy. Meanwhile, the physical functioning of surviving heavy smokers in old age was similar to men 10 years older in the general population. The impact of clustered cardiovascular risk factors was examined by comparing two subcohorts of men who were healthy in 1974, but with different baseline risk factor status. The men with low risk had a 50 % lower mortality during the 29-years follow-up. Their RAND-36 scores for the physical quality of life in old age were significantly better, and the 2002 questionnaire examining psychological well-being indicated also significantly better mental health among the low-risk group. The results indicate that different risk factor levels in midlife have a meaningful impact on life-expectancy and the quality of these extra years. Leading a healthy lifestyle improves both survival and the quality of life.
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The Molecular Adsorbent Recirculating System (MARS) is an extracorporeal albumin dialysis device which is used in the treatment of liver failure patients. This treatment was first utilized in Finland in 2001, and since then, over 200 patients have been treated. The aim of this thesis was to evaluate the impact of the MARS treatment on patient outcome, the clinical and biochemical variables, as well as on the psychological and economic aspects of the treatment in Finland. This thesis encompasses 195 MARS-treated patients (including patients with acute liver failure (ALF), acute-on-chronic liver failure (AOCLF) and graft failure), and a historical control group of 46 ALF patients who did not undergo MARS. All patients received a similar standard medical therapy at the same intensive care unit. The baseline data (demographics, laboratory and clinical variables) and MARS treatment-related and health-related quality-of-life data were recorded before and after treatment. The direct medical costs were determined for a period of 3.5 years.Additionally, the outcome of patients (survival, native liver recovery and need for liver transplantation) and survival predicting factors were investigated. In the outcome analysis, for the MARS-treated ALF patients, their 6-month survival (75% vs. 61%, P=0.07) and their native liver recovery rate (49% vs. 17%, P<0.001) were higher, and their need for transplantations was lower (29% vs. 57%, P= 0.001) than for the historical controls. However, the etiological distribution of the ALF patients referred to our unit has changed considerably over the past decade and the percentage of patients with a more favorable prognosis has increased. The etiology of liver failure was the most important predictor of the outcome. Other survival predicting factors in ALF included hepatic encephalopathy, the coagulation factors and the liver enzyme levels prior to MARS treatment. In terms of prognosis, the MARS treatment of the cirrhotic AOCLF patient seems meaningful only when the patient is eligible for transplantation. The MARS treatment appears to halt the progression of encephalopathy and reduce the blood concentration of neuroactive amino acids, albumin-bound and water-soluble toxins. In general, the effects of the MARS treatment seem to stabilize the patients, thus allowing additional time either for the native liver to recover, or for the patients to endure the prolonged waiting for transplantation. Furthermore, for the ALF patients, the MARS treatment appeared to be less costly and more cost-efficient than the standard medical therapy alone. In conclusion, the MARS treatment appears to have a beneficial effect on the patient outcome in ALF and in those AOCLF patients who can be bridged to transplantation.
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The Dissolved Gas Analysis (DGA) a non destructive test procedure, has been in vogue for a long time now, for assessing the status of power and related transformers in service. An early indication of likely internal faults that may exist in Transformers has been seen to be revealed, to a reasonable degree of accuracy by the DGA. The data acquisition and subsequent analysis needs an expert in the concerned area to accurately assess the condition of the equipment. Since the presence of the expert is not always guaranteed, it is incumbent on the part of the power utilities to requisition a well planned and reliable artificial expert system to replace, at least in part, an expert. This paper presents the application of Ordered Ant Mner (OAM) classifier for the prediction of involved fault. Secondly, the paper also attempts to estimate the remaining life of the power transformer as an extension to the elapsed life estimation method suggested in the literature.
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"Extended Clifford algebras" are introduced as a means to obtain low ML decoding complexity space-time block codes. Using left regular matrix representations of two specific classes of extended Clifford algebras, two systematic algebraic constructions of full diversity Distributed Space-Time Codes (DSTCs) are provided for any power of two number of relays. The left regular matrix representation has been shown to naturally result in space-time codes meeting the additional constraints required for DSTCs. The DSTCs so constructed have the salient feature of reduced Maximum Likelihood (ML) decoding complexity. In particular, the ML decoding of these codes can be performed by applying the lattice decoder algorithm on a lattice of four times lesser dimension than what is required in general. Moreover these codes have a uniform distribution of power among the relays and in time, thus leading to a low Peak to Average Power Ratio at the relays.
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This clinical study focused on effects of childhood specific language impairment (SLI) on daily functioning in late life. SLI is a neurobiological disorder with genetic predisposition and manifests as poor language production or comprehension or both in a child with age-level non-verbal intelligence and no other known cause for deficient language development. The prevalence rate of around 7% puts it among the most prevalent developmental disorders in childhood. Negative long-term effects, such as problems in learning and behavior, are frequent. In follow-up studies the focus has seldom been on self-perception of daily functioning and participation, which are considered important in the International Classification of Functioning, Disability, and Health (ICF). To investigate the self-perceived aspects of everyday functioning in individuals with childhood receptive SLI compared with age- and gender-matched control populations, the 15D, 16D, and 17D health-related quality of life (HRQoL) questionnaires were applied. These generic questionnaires include 15, 16, and 17 dimensions, respectively, and give both a single index score and a profile with values on each dimension. Information on different life domains (rehabilitation, education, employment etc.) from each age-group was collected with separate questionnaires. The study groups comprised adults, adolescents (12-16 years), and pre-adolescents (8-11 years) who had received a diagnosis of receptive SLI and had been examined, usually before school age, at the Department of Phoniatrics of Helsinki University Central Hospital, where children with language deficits caused by various etiologies are examined and treated by a multidisciplinary team. The adult respondents included 33 subjects with a mean age of 34 years. Measured with 15D, the subjects perceived their HRQoL to be nearly as good as that of their controls, but on the dimensions of speech, usual activities, mental functioning, and distress they were significantly worse off. They significantly more often lived with their parents (19%) or were pensioned (26%) than the adult Finnish population on average. Adults with self-perceived problems in finding words and in remembering instructions, manifestations of persistent language impairment, showed inferior every day functioning to the rest of the study group. Of the adolescents and pre-adolescents, 48 and 51, respectively, responded. The majority in both groups had received special education or extra educational support at school. They all had attended speech therapy at some point; at the time of the study only one adolescent, but every third pre-adolescent still received speech therapy. The 16D score of the adolescent or the 17D score of the pre-adolescents did not differ from that of their controls. The 16D profiles differed on some dimensions; subjects were significantly worse off on the dimension of mental functioning, but better off on the dimension of vitality than controls. Of the 17D dimensions, the study group was significantly worse off on speech, whereas the control group reported significantly more problems in sleeping. Of the childhood performance measures investigated, low verbal intelligence quotient (VIQ), which is often considered to reflect receptive language impairment, was in adults subjects significantly associated with some of the self-perceived problems, such as problems in usual activities and mental functioning. The 15D, 16D, and 17D questionnaires served well in measuring self-perceived HRQoL. Such standardized measures with population values are especially important in confirming with the ICF guidelines. In the future these questionnaires could perhaps be used on a more individual level in follow-up of children in clinics, and even in special schools and classes, to detect those children at greatest risk of negative long-term effects and perhaps diminished well-being regarding daily functioning and participation.
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We examine the moving and housing preferences of middle-aged and older in Finland, a country where population composition and movement through the life course are changing. A logistic regression reveals that middle-aged, moderate income residents, renters, those who have lived in their houses only a short time, and residents who are generally dissatisfied are most likely to consider moving. Downsizing appeals to residents with lower incomes who live alone, and who have been in their current houses longer. All potential movers agree on the importance of transportation access and a neighborhood grocery store; however, those preferring to downsize are also interested in house and neighborhood design as well as services that will allow aging in place. Income limitations may create affordability problems for some potential movers.
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A health-monitoring and life-estimation strategy for composite rotor blades is developed in this work. The cross-sectional stiffness reduction obtained by physics-based models is expressed as a function of the life of the structure using a recent phenomenological damage model. This stiffness reduction is further used to study the behavior of measurable system parameters such as blade deflections, loads, and strains of a composite rotor blade in static analysis and forward flight. The simulated measurements are obtained using an aeroelastic analysis of the composite rotor blade based on the finite element in space and time with physics-based damage modes that are then linked to the life consumption of the blade. The model-based measurements are contaminated with noise to simulate real data. Genetic fuzzy systems are developed for global online prediction of physical damage and life consumption using displacement- and force-based measurement deviations between damaged and undamaged conditions. Furthermore, local online prediction of physical damage and life consumption is done using strains measured along the blade length. It is observed that the life consumption in the matrix-cracking zone is about 12-15% and life consumption in debonding/delamination zone is about 45-55% of the total life of the blade. It is also observed that the success rate of the genetic fuzzy systems depends upon the number of measurements, type of measurements and training, and the testing noise level. The genetic fuzzy systems work quite well with noisy data and are recommended for online structural health monitoring of composite helicopter rotor blades.
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Occupational rhinitis is mainly caused by work environment and not by stimuli encountered outside the workplace. It differs from rhinitis that is worsened by, but not mainly caused by, workplace exposures. Occupational rhinitis can develop in response to allergens, inhaled irritants, or corrosive gases. The thesis evaluated the use of challenge tests in occupational rhinitis diagnostics, studied the long-term health-related quality of life among allergic occupational rhinitis patients, and the allergens of wheat grain among occupational respiratory allergy patients. The diagnosed occupational rhinitis was mainly allergic rhinitis, which was caused by occupational agents, most commonly flours and animal allergens. The non-IgE-mediated rhinitis reactions were less frequent and caused more often asthma than rhinitis. Both nasal challenges and inhalation challenges were found to be safe tests. The inhalation challenge tests had considerably resource-intensive methodology. However, the evaluation of nasal symptoms and signs together with bronchial reactions saved time and expense compared with the organization of multiple individual challenges. The scoring criteria used matched well with the weighted amount of discharge ≥ 0.2 g and in most cases gave comparable results. The challenge tests are valuable tools when there is uncertainty whether the patient's exposure should be reduced or discontinued. It was found that continuing exposure decreases health-related quality of life among patients with allergic occupational rhinitis despite of rhinitis medications, still approximately ten years after the diagnosis. Health-related quality of life among occupational rhinitis patients without any longer occupational exposure was mainly similar than that of the healthy controls. This highlights the importance of the reduction and cessation of occupational exposure. To achieve this, 17% of occupational rhinitis patients had been re-educated. Alpha-amylase inhibitors, lipid transfer protein 2G, thaumatin -like protein, and peroxidase I were found to be relevant allergens in Finnish patients with occupational respiratory wheat allergy. Of these allergens, thaumatin-like protein and lipid transfer protein 2G were found as new allergens associated with baker's rhinitis and asthma. The knowledge of the new clinically relevant proteins can be used in the future in the development of better standardized diagnostic preparations.
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Introduction Patients post sepsis syndromes have a poor quality of life and a high rate of recurring illness or mortality. Follow-up clinics have been instituted for patients postgeneral intensive care but evidence is sparse, and there has been no clinic specifically for survivors of sepsis. The aim of this trial is to investigate if targeted screening and appropriate intervention to these patients can result in an improved quality of life (Short Form 36 health survey (SF36V.2)), decreased mortality in the first 12 months, decreased readmission to hospital and/or decreased use of health resources. Methods and analysis 204 patients postsepsis syndromes will be randomised to one of the two groups. The intervention group will attend an outpatient clinic two monthly for 6 months and receive screening and targeted intervention. The usual care group will remain under the care of their physician. To analyse the results, a baseline comparison will be carried out between each group. Generalised estimating equations will compare the SF36 domain scores between groups and across time points. Mortality will be compared between groups using a Cox proportional hazards (time until death) analysis. Time to first readmission will be compared between groups by a survival analysis. Healthcare costs will be compared between groups using a generalised linear model. Economic (health resource) evaluation will be a within-trial incremental cost utility analysis with a societal perspective. Ethics and dissemination Ethical approval has been granted by the Royal Brisbane and Women’s Hospital Human Research Ethics Committee (HREC; HREC/13/QRBW/17), The University of Queensland HREC (2013000543), Griffith University (RHS/08/14/HREC) and the Australian Government Department of Health (26/2013). The results of this study will be submitted to peer-reviewed intensive care journals and presented at national and international intensive care and/or rehabilitation conferences.
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Exercise that targets ankle joint mobility may lead to improvement in calf muscle pump function and subsequent healing. The objectives of this research were to assess the impact of an exercise intervention in addition to routine evidence-based care on the healing rates, functional ability and health-related quality of life for adults with venous leg ulcers (VLUs). This study included 63 patients with VLUs. Patients were randomised to receive either a 12-week exercise intervention with a telephone coaching component or usual care plus telephone calls at the same timepoints. The primary outcome evaluated the effectiveness of the intervention in relation to wound healing. The secondary outcomes evaluated physical activity, functional ability and health-related quality of life measures between groups at the end of the 12 weeks. A per protocol analysis complemented the effectiveness (intention-to-treat) analysis to highlight the importance of adherence to an exercise intervention. Intention-to-treat analyses for the primary outcome showed 77% of those in the intervention group healed by 12 weeks compared to 53% of those in the usual care group. Although this difference was not statistically significant due to a smaller than expected sample size, a 24% difference in healing rates could be considered clinically significant. The per protocol analysis for wound healing, however, showed that those in the intervention group who adhered to the exercise protocol 75% or more of the time were significantly more likely to heal and showed higher rates for wound healing than the control group (P = 0·01), that is, 95% of those who adhered in the intervention group healed in 12 weeks. The secondary outcomes of physical activity, functional ability and health-related quality of life were not significantly altered by the intervention. Among the secondary outcomes (physical activity, functional ability and health-related quality of life), intention-to-treat analyses did not support the effectiveness of the intervention. However, per protocol analyses revealed encouraging results with those participants who adhered more than 75% of the time (n = 19) showing significantly improved Range of Ankle Motion from the self-management exercise programme (P = 0·045). This study has shown that those participants who adhere to the exercise programme as an adjunctive treatment to standard care are more likely to heal and have better functional outcomes than those who do not adhere to the exercises in conjunction with usual care.
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Cyclosporine is an immunosuppressant drug with a narrow therapeutic index and large variability in pharmacokinetics. To improve cyclosporine dose individualization in children, we used population pharmacokinetic modeling to study the effects of developmental, clinical, and genetic factors on cyclosporine pharmacokinetics in altogether 176 subjects (age range: 0.36–20.2 years) before and up to 16 years after renal transplantation. Pre-transplantation test doses of cyclosporine were given intravenously (3 mg/kg) and orally (10 mg/kg), on separate occasions, followed by blood sampling for 24 hours (n=175). After transplantation, in a total of 137 patients, cyclosporine concentration was quantified at trough, two hours post-dose, or with dose-interval curves. One-hundred-four of the studied patients were genotyped for 17 putatively functionally significant sequence variations in the ABCB1, SLCO1B1, ABCC2, CYP3A4, CYP3A5, and NR1I2 genes. Pharmacokinetic modeling was performed with the nonlinear mixed effects modeling computer program, NONMEM. A 3-compartment population pharmacokinetic model with first order absorption without lag-time was used to describe the data. The most important covariate affecting systemic clearance and distribution volume was allometrically scaled body weight i.e. body weight**3/4 for clearance and absolute body weight for volume of distribution. The clearance adjusted by absolute body weight declined with age and pre-pubertal children (< 8 years) had an approximately 25% higher clearance/body weight (L/h/kg) than did older children. Adjustment of clearance for allometric body weight removed its relationship to age after the first year of life. This finding is consistent with a gradual reduction in relative liver size towards adult values, and a relatively constant CYP3A content in the liver from about 6–12 months of age to adulthood. The other significant covariates affecting cyclosporine clearance and volume of distribution were hematocrit, plasma cholesterol, and serum creatinine, explaining up to 20%–30% of inter-individual differences before transplantation. After transplantation, their predictive role was smaller, as the variations in hematocrit, plasma cholesterol, and serum creatinine were also smaller. Before transplantation, no clinical or demographic covariates were found to affect oral bioavailability, and no systematic age-related changes in oral bioavailability were observed. After transplantation, older children receiving cyclosporine twice daily as the gelatine capsule microemulsion formulation had an about 1.25–1.3 times higher bioavailability than did the younger children receiving the liquid microemulsion formulation thrice daily. Moreover, cyclosporine oral bioavailability increased over 1.5-fold in the first month after transplantation, returning thereafter gradually to its initial value in 1–1.5 years. The largest cyclosporine doses were administered in the first 3–6 months after transplantation, and thereafter the single doses of cyclosporine were often smaller than 3 mg/kg. Thus, the results suggest that cyclosporine displays dose-dependent, saturable pre-systemic metabolism even at low single doses, whereas complete saturation of CYP3A4 and MDR1 (P-glycoprotein) renders cyclosporine pharmacokinetics dose-linear at higher doses. No significant associations were found between genetic polymorphisms and cyclosporine pharmacokinetics before transplantation in the whole population for which genetic data was available (n=104). However, in children older than eight years (n=22), heterozygous and homozygous carriers of the ABCB1 c.2677T or c.1236T alleles had an about 1.3 times or 1.6 times higher oral bioavailability, respectively, than did non-carriers. After transplantation, none of the ABCB1 SNPs or any other SNPs were found to be associated with cyclosporine clearance or oral bioavailability in the whole population, in the patients older than eight years, or in the patients younger than eight years. In the whole population, in those patients carrying the NR1I2 g.-25385C–g.-24381A–g.-205_-200GAGAAG–g.7635G–g.8055C haplotype, however, the bioavailability of cyclosporine was about one tenth lower, per allele, than in non-carriers. This effect was significant also in a subgroup of patients older than eight years. Furthermore, in patients carrying the NR1I2 g.-25385C–g.-24381A–g.-205_-200GAGAAG–g.7635G–g.8055T haplotype, the bioavailability was almost one fifth higher, per allele, than in non-carriers. It may be possible to improve individualization of cyclosporine dosing in children by accounting for the effects of developmental factors (body weight, liver size), time after transplantation, and cyclosporine dosing frequency/formulation. Further studies are required on the predictive value of genotyping for individualization of cyclosporine dosing in children.
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In order to predict the current state and future development of Earth s climate, detailed information on atmospheric aerosols and aerosol-cloud-interactions is required. Furthermore, these interactions need to be expressed in such a way that they can be represented in large-scale climate models. The largest uncertainties in the estimate of radiative forcing on the present day climate are related to the direct and indirect effects of aerosol. In this work aerosol properties were studied at Pallas and Utö in Finland, and at Mount Waliguan in Western China. Approximately two years of data from each site were analyzed. In addition to this, data from two intensive measurement campaigns at Pallas were used. The measurements at Mount Waliguan were the first long term aerosol particle number concentration and size distribution measurements conducted in this region. They revealed that the number concentration of aerosol particles at Mount Waliguan were much higher than those measured at similar altitudes in other parts of the world. The particles were concentrated in the Aitken size range indicating that they were produced within a couple of days prior to reaching the site, rather than being transported over thousands of kilometers. Aerosol partitioning between cloud droplets and cloud interstitial particles was studied at Pallas during the two measurement campaigns, First Pallas Cloud Experiment (First PaCE) and Second Pallas Cloud Experiment (Second PaCE). The method of using two differential mobility particle sizers (DMPS) to calculate the number concentration of activated particles was found to agree well with direct measurements of cloud droplet. Several parameters important in cloud droplet activation were found to depend strongly on the air mass history. The effects of these parameters partially cancelled out each other. Aerosol number-to-volume concentration ratio was studied at all three sites using data sets with long time-series. The ratio was found to vary more than in earlier studies, but less than either aerosol particle number concentration or volume concentration alone. Both air mass dependency and seasonal pattern were found at Pallas and Utö, but only seasonal pattern at Mount Waliguan. The number-to-volume concentration ratio was found to follow the seasonal temperature pattern well at all three sites. A new parameterization for partitioning between cloud droplets and cloud interstitial particles was developed. The parameterization uses aerosol particle number-to-volume concentration ratio and aerosol particle volume concentration as the only information on the aerosol number and size distribution. The new parameterization is computationally more efficient than the more detailed parameterizations currently in use, but the accuracy of the new parameterization was slightly lower. The new parameterization was also compared to directly observed cloud droplet number concentration data, and a good agreement was found.
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This thesis studies quantile residuals and uses different methodologies to develop test statistics that are applicable in evaluating linear and nonlinear time series models based on continuous distributions. Models based on mixtures of distributions are of special interest because it turns out that for those models traditional residuals, often referred to as Pearson's residuals, are not appropriate. As such models have become more and more popular in practice, especially with financial time series data there is a need for reliable diagnostic tools that can be used to evaluate them. The aim of the thesis is to show how such diagnostic tools can be obtained and used in model evaluation. The quantile residuals considered here are defined in such a way that, when the model is correctly specified and its parameters are consistently estimated, they are approximately independent with standard normal distribution. All the tests derived in the thesis are pure significance type tests and are theoretically sound in that they properly take the uncertainty caused by parameter estimation into account. -- In Chapter 2 a general framework based on the likelihood function and smooth functions of univariate quantile residuals is derived that can be used to obtain misspecification tests for various purposes. Three easy-to-use tests aimed at detecting non-normality, autocorrelation, and conditional heteroscedasticity in quantile residuals are formulated. It also turns out that these tests can be interpreted as Lagrange Multiplier or score tests so that they are asymptotically optimal against local alternatives. Chapter 3 extends the concept of quantile residuals to multivariate models. The framework of Chapter 2 is generalized and tests aimed at detecting non-normality, serial correlation, and conditional heteroscedasticity in multivariate quantile residuals are derived based on it. Score test interpretations are obtained for the serial correlation and conditional heteroscedasticity tests and in a rather restricted special case for the normality test. In Chapter 4 the tests are constructed using the empirical distribution function of quantile residuals. So-called Khmaladze s martingale transformation is applied in order to eliminate the uncertainty caused by parameter estimation. Various test statistics are considered so that critical bounds for histogram type plots as well as Quantile-Quantile and Probability-Probability type plots of quantile residuals are obtained. Chapters 2, 3, and 4 contain simulations and empirical examples which illustrate the finite sample size and power properties of the derived tests and also how the tests and related graphical tools based on residuals are applied in practice.