968 resultados para Half a life


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Bone stress injuries of the foot have been known for more than 150 years. For a century, their primary diagnostic imaging tool has been radiography. However, currently the golden standard for establishing the diagnosis of stress injuries is magnetic resonance imaging (MRI). Although the injury type has been fairly well documented in the earlier literature, little information is available on the healing of stress injuries located in e.g. the talus and calcaneus. The current study retrospectively evaluated the stress injuries of the foot and ankle treated at the Central Military Hospital over a period of eight years in patients who underwent MRI for stress injury of the foot. The imaging studies of the patients were reevaluated to determine the exact nature of the stress injury. Moreover, the hospital records of the patients were reviewed to determine the healing of stress injuries of the talus and calcaneus. Patients with a stress fracture in the talus were recalled for a follow-up examination and MRI scan one to six years after the initial injury to determine if the fracture had completely healed, clinically and radiologically. The bone stress injuries of the foot were found to affect more than one bone in a majority of the cases. The talus and the calcaneus were the bones most commonly affected. In the talus, the most common site for the injuries was the head of the bone, and in the calcaneus, the posterior part of the bone. The injuries in these bones were associated with injuries in the surrounding bones. Stress injuries in the calcaneus seemed to heal well. No complications were seen in the primary healing process. The patients were, however, sometimes compelled to refrain from physical training for up to months. In the talus, minor degenerative findings of the articular surface were seen in half of the patients who participated in a follow-up MRI scan and radiographs taken one to six years after the initial injury. Half of the patients also reported minor exercise related symptoms in the follow-up. The symptoms were, however, not noticeable in everyday life.

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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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Inadvertent failure of power transformers has serious consequences on the power system reliability, economics and the revenue accrual. Insulation is the weakest link in the power transformer prompting periodic inspection of the status of insulation at different points in time. A close Monitoring of the electrical, chemical and such other properties on insulation as are sensitive to the amount of time-dependent degradation becomes mandatory to judge the status of the equipment. Data-driven Diagnostic Testing and Condition Monitoring (DTCM) specific to power transformer is the aspect in focus. Authors develop a Monte Carlo approach for augmenting the rather scanty experimental data normally acquired using Proto-types of power transformers. Also described is a validation procedure for estimating the accuracy of the Model so developed.

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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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Gastric motility disorders, including delayed gastric emptying (gastroparesis), impaired postprandial fundic relaxation, and gastric myoelectrical disorders, can occur in type 1 diabetes, chronic renal failure, and functional dyspepsia (FD). Symptoms like upper abdominal pain, early satiation, bloating, nausea and vomiting may be related to gastroparesis. Diabetic gastroparesis is related to autonomic neuropathy. Scintigraphy is the gold standard in measuring gastric emptying, but it is expensive, requires specific equipment, and exposes patients to radiation. It also gives information about the intragastric distribution of the test meal. The 13C-octanoic acid breath test (OBT) is an alternative, indirect method of measuring gastric emptying with a stable isotope. Electrogastrography (EGG) registers the slow wave originating in the pacemaker area of the stomach and regulating the peristaltic contractions of the antrum. This study compares these three methods of measuring gastric motility in patients with type 1 diabetes, functional dyspepsia, and chronic renal failure. Currently no effective drugs for treating gastric motility disorders are available. We studied the effect of nizatidine on gastric emptying, because in preliminary studies this drug has proven to have a prokinetic effect due to its cholinergic properties. Of the type 1 patients, 26% had delayed gastric emptying of solids as measured by scintigraphy. Abnormal intragastric distribution of the test meal occurred in 37% of the patients, indicating impaired fundic relaxation. The autonomic neuropathy score correlated positively with the gastric emptying rate of solids (P = 0.006), but HbA1C, plasma glucose levels, or abdominal symptoms were unrelated to gastric emptying or intragastric distribution of the test meal. Gastric emptying of both solids and liquids was normal in all FD patients but abnormal intragastric distribution occurred in 38% of the patients. Nizatidine improved symptom scores and quality of life in FD patients, but not significantly. Instead of enhancing, nizatidine slowed gastric emptying in FD patients (P < 0.05). No significant difference appeared in the frequency of the gastric slow waves measured by EGG in the patients and controls. The correlation between gastric half-emptying times of solids measured by scintigraphy and OBT was poor both in type 1 diabetes and FD patients. According to this study, dynamic dual-tracer scintigraphy is more accurate than OBT or EGG in measuring gastric emptying of solids. Additionally it provides information about gastric emptying of liquids and the intragastric distribution of the ingested test meal.

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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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1. Whether life-history traits can determine community composition and structure is an important question that has been well explored theoretically, but has received scant empirical attention. Life-history traits of a seven-member community of galler and parasitoid fig wasp species (Chalcidoidea), developing within the inflorescences (syconia) of Ficus racemosa (Moraceae) in India, were determined and used to examine community structure and ecology. 2. Gallers were pro-ovigenic (all eggs are mature upon adult emergence) whereas parasitoids were synovigenic (eggs mature progressively during adult lifespan). Initial egg load was correlated with body size for some species, and there was a trade-off between egg number and egg size across all species. Although all species completed their development and left the syconium concurrently, they differed in their adult and pre-adult lifespans. Providing sucrose solutions increased parasitoid lifespan but had no effect on the longevity of some galler species. While feeding regimes and body size affected longevity in most species, an interaction effect between these variables was detected for only one species. 3. Life-history traits of wasp species exhibited a continuum in relation to their arrival sequence at syconia for oviposition during syconium development, and therefore reflected their ecology. The largest number of eggs, smallest egg sizes, and shortest longevities were characteristic of the earliest-arriving galling wasps at the smallest, immature syconia; the converse characterised the later-arriving parasitoids at the larger, already parasitised syconia. Thus life history is an important correlate of community resource partitioning and can be used to understand community structure. 4. This is the first comprehensive study of life-history traits in a fig wasp community. The comparative approach revealed constraints and flexibility in trait evolution.

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Quality of life (QoL) and Health-related quality of life (HRQoL) are becoming one of the key outcomes of health care due to increased respect for the subjective valuations and well-being of patients and an increasing part of the ageing population living with chronic, non-fatal conditions. Preference-based HRQoL measures enable estimation of health utility, which can be useful for rational rationing, evidence-based medicine and health policy. This study aimed to compare the individual severity and public health burden of major chronic conditions in Finland, including and focusing on reliably diagnosed psychiatric conditions. The study is based on the Health 2000 survey, a representative general population survey of 8028 Finns aged 30 and over. Depressive, anxiety and alcohol use disorders were diagnosed with the Composite International Diagnostic Interview (M-CIDI). HRQoL was measured with the 15D and the EQ-5D, with 83% response rate. This study found that people with psychiatric disorders had the lowest 15D HRQoL scores at all ages, in comparison to other main groups of chronic conditions. Considering 29 individual conditions, three of the four most severe (on 15D) were psychiatric disorders; the most severe was Parkinson s disease. Of the psychiatric disorders, chronic conditions that have sometimes been considered relatively mild - dysthymia, agoraphobia, generalized anxiety disorder and social phobia - were found to be the most severe. This was explained both by the severity of the impact of these disorders on mental health domains of HRQoL, and also by the fact that decreases were widespread on most dimensions of HRQoL. Considering the public health burden of conditions, musculoskeletal disorders were associated with the largest burden, followed by psychiatric disorders. Psychiatric disorders were associated with the largest burden at younger ages. Of individual conditions, the largest burden found was for depressive disorders, followed by urinary incontinence and arthrosis of the hip and knee. The public health burden increased greatly with age, so the ageing of the Finnish population will mean that the disease burden caused by chronic conditions will increase by a quarter up to year 2040, if morbidity patterns do not change. Investigating alcohol consumption and HRQoL revealed that although abstainers had poorer HRQoL than moderate drinkers, this was mainly due to many abstainers being former drinkers and having the poorest HRQoL. Moderate drinkers did not have significantly better HRQoL than abstainers who were not former drinkers. Psychiatric disorders are associated with a large part of the non-fatal disease burden in Finland. In particular anxiety disorders appear to be more severe and have a larger public health burden than previously thought.

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Sormen koukistajajännevamman korjauksen jälkeisen aktiivisen mobilisaation on todettu johtavan parempaan toiminnalliseen lopputulokseen kuin nykyisin yleisesti käytetyn dynaamisen mobilisaation. Aktiivisen mobilisaation ongelma on jännekorjauksen pettämisriskin lisääntyminen nykyisten ommeltekniikoiden riittämättömän vahvuuden vuoksi. Jännekorjauksen lujuutta on parannettu kehittämällä monisäieommeltekniikoita, joissa jänteeseen tehdään useita rinnakkaisia ydinompeleita. Niiden kliinistä käyttöä rajoittaa kuitenkin monimutkainen ja aikaa vievä tekninen suoritus. Käden koukistajajännekorjauksessa käytetään yleisesti sulamattomia ommelmateriaaleja. Nykyiset käytössä olevat biohajoavat langat heikkenevät liian nopeasti jänteen paranemiseen nähden. Biohajoavan laktidistereokopolymeeri (PLDLA) 96/4 – langan vetolujuuden puoliintumisajan sekä kudosominaisuuksien on aiemmin todettu soveltuvan koukistajajännekorjaukseen. Tutkimuksen tavoitteena oli kehittää välittömän aktiivisen mobilisaation kestävä ja toteutukseltaan yksinkertainen käden koukistajajännekorjausmenetelmä biohajoavaa PLDLA 96/4 –materiaalia käyttäen. Tutkimuksessa analysoitiin viiden eri yleisesti käytetyn koukistajajänneompeleen biomekaanisia ominaisuuksia staattisessa vetolujuustestauksessa ydinompeleen rakenteellisten ominaisuuksien – 1) säikeiden (lankojen) lukumäärän, 2) langan paksuuden ja 3) ompeleen konfiguraation – vaikutuksen selvittämiseksi jännekorjauksen pettämiseen ja vahvuuteen. Jännekorjausten näkyvän avautumisen todettiin alkavan perifeerisen ompeleen pettäessä voima-venymäkäyrän myötöpisteessä. Ydinompeleen lankojen lukumäärän lisääminen paransi ompeleen pitokykyä jänteessä ja suurensi korjauksen myötövoimaa. Sen sijaan paksumman (vahvemman) langan käyttäminen tai ompeleen konfiguraatio eivät vaikuttaneet myötövoimaan. Tulosten perusteella tutkittiin mahdollisuuksia lisätä ompeleen pitokykyä jänteestä yksinkertaisella monisäieompeleella, jossa ydinommel tehtiin kolmen säikeen polyesterilangalla tai nauhamaisen rakenteen omaavalla kolmen säikeen polyesterilangalla. Nauhamainen rakenne lisäsi merkitsevästi ompeleen pitokykyä jänteessä parantaen myötövoimaa sekä maksimivoimaa. Korjauksen vahvuus ylitti aktiivisen mobilisaation jännekorjaukseen kohdistaman kuormitustason. PLDLA 96/4 –langan soveltuvuutta koukistajajännekorjaukseen selvitettiin tutkimalla langan biomekaanisia ominaisuuksia ja solmujen pito-ominaisuuksia staattisessa vetolujuustestauksessa verrattuna yleisimmin jännekorjauksessa käytettävään punottuun polyesterilankaan (Ticron®). PLDLA –langan todettiin soveltuvan hyvin koukistajajännekorjaukseen, sillä se on polyesterilankaa venymättömämpi ja solmujen pitävyys on parempi. Viimeisessä vaiheessa tutkittiin PLDLA 96/4 –langasta valmistetulla kolmisäikeisellä, nauhamaisella jännekorjausvälineellä tehdyn jännekorjauksen kestävyyttä staattisessa vetolujuustestauksessa sekä syklisessä kuormituksessa, joka simuloi staattista testausta paremmin mobilisaation toistuvaa kuormitusta. PLDLA-korjauksen vahvuus ylitti sekä staattisessa että syklisessä kuormituksessa aktiivisen mobilisaation edellyttämän vahvuuden. Nauhamaista litteää ommelmateriaalia ei aiemmin ole tutkittu tai käytetty käden koukistajajännekorjauksessa. Tässä tutkimuksessa ommelmateriaalin nauhamainen rakenne paransi merkitsevästi jännekorjauksen vahvuutta, minkä arvioidaan johtuvan lisääntyneestä kontaktipinnasta jänteen ja ommelmateriaalin välillä estäen ompeleen läpileikkautumista jänteessä. Tutkimuksessa biohajoavasta PLDLA –materiaalista valmistetulla rakenteeltaan nauhamaisella kolmisäikeisellä langalla tehdyn jännekorjauksen vahvuus saavutti aktiivisen mobilisaation edellyttämän tason. Lisäksi uusi menetelmä on helppokäyttöinen ja sillä vältetään perinteisten monisäieompeleiden tekniseen suoritukseen liittyvät ongelmat.

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Previous studies have shown a relationship between the use of communications technology and well-being, particularly mediated through its effect on personal relationships. However, there is some debate over whether this effect is positive or negative. The present study explored this issue further, examining whether the effect varies depending on the type of communications technology, and the nature of the personal relationship. An online survey was conducted with 3,421 participants in three countries (Australia, UK and US). It examined the use of ten communication methods, overall satisfaction with life and satisfaction with four different kinds of relationships (close and extended family, and close and distant friends). Results indicate that richer communication methods, which include non-verbal cues, were positively associated with both overall satisfaction with life and satisfaction with relationships. These methods included face-to-face communication, and phone and video calls. Conversely, more restricted methods, such as text messaging and instant messaging, were negatively associated with both variables. Social networking was negatively associated with overall satisfaction, but not with satisfaction with relationships. The strength of the association between a communications method and satisfaction with a relationship varied depending on the type of relationship, but whether it was positive or negative did not change.

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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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Jarvis et al. (Research Articles, 12 December 2014, p. 1320) presented molecular clock analyses that suggested that most modern bird orders diverged just after the mass extinction event at the Cretaceous-Paleogene boundary (about 66 million years ago). We demonstrate that this conclusion results from the use of a single inappropriate maximum bound, which effectively precludes the Cretaceous diversification overwhelmingly supported by previous molecular studies.