885 resultados para Disturbances
Resumo:
Yleisesti sähkönjakelussa käytettyä vaihtosähköä ollaan korvaamassa tasasähköllä pienjänniteverkoissa. Vaihtojännitteeseen verrattuna tasajännitteen käyttö mahdollistaa korkeampien jännitetasojen käytön ja paremman sähkönlaadun ja sitä kautta paremman käyttövarmuuden. Sähköverkossa käytettävien muuntajien ja suuntaajien osalta tarvitaan uudenlaisia rakenteita ja kehitystä, että tasajännitejakelun käyttöönotto olisi mahdollista. Oikeiden ratkaisujen löytämiseksi on tehty jo paljon tutkimusta, mutta valmiita järjestelmiä ei vielä ole laajemmin otettu käyttöön. Tasajänniteverkot tarvitsevat myös ohjauksen, säädön ja valvonnan takia tiedonsiirto-ominaisuuksia. Tietoa on mahdollista siirtää samassa kaapelissa, jota käytetään myös sähkön siirtoon. Haasteita asettavat mm. kaapeliin kytketyminen ja tiedonsiirtokanavassa esiintyvät häiriöt. Työssä muodostetaan malli tiedonsiirtokanavasta, jonka avulla voidaan mallintaa verkon käyttäytymistä eri taajuuksilla sekä simuloida sähköverkkoon muodostettavia tiedonsiirtokanavia.
Resumo:
OBJECTIVES: Disturbances in eating behavior significantly affect young adults. This study aimed to estimate the prevalence of abnormal eating behaviors, according to the Eating Attitudes Test - 26 (EAT-26) in medical students at a university in southern Santa Catarina State, Brazil. METHODS: Self-reported questionnaire, based on the EAT-26 scale, was administered to medical students. Additional questions about age, gender, study period of the course, weight and height were asked. A total of 391 medical students were assessed, amounting to 93.3 percent of the 419 students enrolled. RESULTS: Ten percent of the surveyed subjects had positive EAT-26 scores. This outcome measure was positive associated with females (PR 6.5), body mass index (BMI) ≤ 25 kg/m² (PR 4.5), age ≤ 20 years (PR 1.3) and being student from 1st to 5th semester of the course (PR 1.7). A higher proportion of women gave positive responses to behaviors related to control of food intake or weight loss than men. CONCLUSION: The significant prevalence of behaviors related to eating disorders, predominantly among women, suggests the implementation of preventive measures targeting this population.
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Hehkulamput tullaan kieltämään Euroopan Unionin alueella vuoden 2016 syyskuuhun mennessä. Hehkulamput korvataan suurimmaksi osaksi pienloistelampuilla, jotka omaavat hehkulamppuihin verrattuna paremman hyötysuhteen. Pienloistelamput aiheuttavat kuitenkin häiriöitä niitä syöttävään sähköverkkoon. Tässä kandidaatin työssä mitattiin 15 erilaisen pienloistelampun aiheuttamat johtuvat RF-taajuiset häiriöt. Tuloksia verrattiin CISPR 15 – standardissa esitettyihin raja-arvoihin, joita pienloistelamppujen tulisi noudattaa. Mittaukset suoritettiin käyttämällä CISPR 16 –standardin kanssa yhteensopivaa mittavastaanotinta (Rohde & Schwarz ESHS30) sekä myöskin CISPR 16 yhteensopivaa keinoverkkoa (Rohde & Schwarz ESH2Z5). Lamput mitattiin CISPR 15 –standardin mukaisesti, muutamia poikkeuksia lukuun ottamatta. Lamppuja ei mitattu käyttämällä CISPR 15 –standardissa vaadittua lampun pidintä. Eikä lamppuja myöskään esikäytetty ollenkaan. Lukuun ottamatta yhtä pienloistelamppua, kaikki jäivät raja-arvon alapuolelle. Rajan ylittäneen lampun tulos tosin mahtuu mittavastaanottimen mittavirheeseen. Joten kyseessä ei ollut suuren suuri ylitys. Muiden tutkittujen pienloistelamppujen johtuvat RF-häiriöt ovat hyväksyttävällä tasolla ja ne tuskin tulevat aiheuttamaan ongelmia.
Resumo:
Epileptic seizures are harmful to the developing brain. During epileptic seizures, overactivation of glutamate receptors (GluR) leads to neuronal degeneration, defined as excitotoxicity. The hippocampus is especially vulnerable to excitotoxic neuronal death, but its mechanism has remained incompletely known in the developing brain. Recently, signs of activation of inflammatory processes after epileptic seizures have been detected in the hippocampus. The purpose of this thesis was to study the inflammatory reaction and death mechanisms in excitoxic neurodegeneration induced by the glutamate analogue kainic acid (KA) in the developing hippocampus. Organotypic hippocampal slice cultures (OHCs), prepared from 6-7-day-old rats (P6-7) and treated with KA, served as an in vitro model. KA-induced status epilepticus in P9 and P21 rats was used as an in vivo model. The results showed that the pyramidal cell layers of the hippocampus were the most susceptible to irreversible and age-specific neurodegeneration, which occurred in the juvenile (P21), but not in the immature (P9), rat hippocampus. The primary death mechanism was necrosis as there were no significant changes in the expression of selected apoptosis markers and morphological cellular features of necrosis were found. Inflammatory response was similarly age-dependent after KA treatment as a rapid, fulminant and wide response was detected in the juvenile, but not in the immature, rat brain. An anti-inflammatory drug treatment, given before KA, was not neuroprotective in OHCs, possibly because of the timing of the treatment. In summary, the results suggest that KA induces an age-dependent inflammatory response and necrotic neurodegeneration, which may cause disturbances in hippocampal connectivity and promote epileptogenesis.
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Background: Metabolic syndrome (MetS) is a combination of several cardio-metabolic risk factors including obesity, hyperglycemia, hypertension and dyslipidemia. MetS has been associated with increased levels of apolipoprotein B (apoB) and low-density lipoprotein oxidation (OxLDL) and with an increased risk of cardiovascular disease and non-alcoholic fatty liver disease. Aims: To establish the relation of apoB and OxLDL with the MetS development and to determine the status of MetS as a risk factor for adverse liver changes and for subclinical atherosclerosis. Subjects and Methods: The present thesis is part of the two large scale population-based, prospective, observational studies. Cardiovascular Risk in Young Finns study was launched in 1980 including 3,596 subjects aged 3-18 years. Thereafter follow-up studies have been conducted regularly. In the latest follow-ups that were performed in 2001 (N=2,283) and 2007 (N=2,204), non-invasive ultrasound studies were introduced to the study protocol to measure subclinical atherosclerosis i.e. carotid intima-media thickness (IMT), carotid artery distensibility (Cdist) and brachial flow-mediated dilatation (FMD). Alanine-aminotransferase (ALT) and gammaglutamyltransferase (GGT) were measured in 2007 to assess liver function. The Bogalusa Heart Study is a long-term epidemiologic study of cardiovascular risk factors launched in 1972 in a biracial community of Bogalusa, Louisiana, USA. Total of 374 youths (aged 9-18 years at baseline in 1984-88) who underwent non-invasive ultrasound studies of the carotid artery as adults, were included in the analyses of the present thesis. Results: The odds ratios (95% confidence intervals) for MetS incidence during a 6-year follow-up by quartiles of apoB were 2.0(1.0-3.8) for the second quartile, 3.1(1.7-5.7) for the third quartile and 4.2(2.3-7.6) for the fourth quartile. OxLDL was not independently associated with incident MetS. Youth (aged 9-18 years) with MetS or with high body mass index were at 2-3 times the risk of having MetS, high IMT, and type 2 diabetes 24-years later as adults. IMT increased 79±7μm (mean±SEM) in subjects with MetS and 42±2μm in subjects without the MetS (P<0.0001) during 6- years. Subjects who lost the MetS diagnosis during 6-year follow-up had reduced IMT progression compared to persistent MetS group (0.036±0.005vs.0.079±0.010 mm, P=0.001) and reduced Cdist change compared to incident MetS group (-0.12±0.05vs.-0.38±0.10 %/mmHg, P=0.03) over 6-year follow-up. MetS predicted elevated ALT (β±SEM=0.380±0.052, P<0.0001 in men and 0.160±0.052, P=0.002 in women) and GGT (β±SEM=0.240±0.058, P<0.0001 in men and 0.262±0.053, P<0.0001 in women) levels after 6-years. Conclusions: These findings suggest that apoB may give additional information on early metabolic disturbances predisposing MetS. MetS may be used to identify individuals at increased risk of developing atherosclerosis and non-alcoholic liver disease. However, recovery from the MetS may have positive effects on liver and vascular properties.
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The time required to regrowth a forest in degraded areas depends on how the forest is removed and on the type of land use following removal. Natural regeneration was studied in abandoned old fields after intensive agricultural land use in areas originally covered by Brazilian Atlantic Forests of the Anchieta Island, Brazil in order to understand how plant communities reassemble following human disturbances as well as to determine suitable strategies of forest restoration. The fields were classified into three vegetation types according to the dominant plant species in: 1) Miconia albicans (Sw.) Triana (Melastomataceae) fields, 2) Dicranopteris flexuosa (Schrader) Underw. (Gleicheniaceae) thickets, and 3) Gleichenella pectinata (Willd.) Ching. (Gleicheniaceae) thickets. Both composition and structure of natural regeneration were compared among the three dominant vegetation types by establishing randomly three plots of 1 x 3 m in five sites of the island. A gradient in composition and abundance of species in natural regeneration could be observed along vegetation types from Dicranopteris fern thickets to Miconia fields. The gradient did not accurately follow the pattern of spatial distribution of the three dominant vegetation types in the island regarding their proximity of the remnant forests. A complex association of biotic and abiotic factors seems to be affecting the seedling recruitment and establishment in the study plots. The lowest plant regeneration found in Dicranopteris and Gleichenella thickets suggests that the ferns inhibit the recruitment of woody and herbaceous species. Otherwise, we could not distinguish different patterns of tree regeneration among the three vegetation types. Our results showed that forest recovery following severe anthropogenic disturbances is not direct, predictable or even achievable on its own. Appropriated actions and methods such as fern removal, planting ground covers, and enrichment planting with tree species were suggested in order to restore the natural forest regeneration process in the abandoned old fields.
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The overall goal of the study was to describe adoption of information technology (IT)-based patient education (PE) developed for patients and nurses use in psychiatric nursing. The data were collected in three phases during the period 2000-2006 in a variety of psychiatric settings in Finland. Firstly, the development process of IT-based PE for patients with schizophrenia spectrum psychosis was described. Secondly, nurses’ adoption of IT-based PE and the variables explaining adoption were demonstrated. Moreover, use of daily IT-based PE in clinical practice and factors associated with use were identified and described. And thirdly, nurses’ experiences of the IT-based PE after one year clinical use were evaluated. IT-based PE program was developed in several stages based on users’ needs and it included information and multimedia applications. Altogether, almost 500 IT-based PE sessions were carried out by the nurses on the study wards and revealed nurses’ activity in educating patients using IT to vary and depend on the hospital in which they worked. Almost 80% of all the possible IT-based PE sessions involved 93 patients and 83 nurses. Less than 2% of the IT-based PE sessions were interrupted and less than 10% suffered disturbances due to the patients or external causes. Moreover, the patients whose education took more days had poorer mental status than those whose education was carried out over a shorter period. After a year’s experience, advantages and disadvantages were described by the nurses for both patients and nurses of the IT-based PE. IT-based PE can be used even on closed acute psychiatric wards with patients with serious mental health disorders. However, technology adoption requires time, and therefore, it must fit in with clinical practice. Collaboration between users and developers is needed when developing user-centered methods in the area of mental health services. Moreover, it is important to understand factors that affect IT adoption in healthcare settings. IT-based PE is one option in interactive and co-operative health care practice between patients and nurses. Therefore the staff should begin to refer patients to established, credible and well-maintained Internet sites that provide information on common psychological problems. Even if every nurse should be trained and engaged to carry out IT-based PE, by targeting the training especially for the most active nurses aids them to support the less active ones. Adoption should also be understood from a perspective that includes aspects related to the context where it is implemented and examine how and in what circumstances it works.
Resumo:
Työssä esitellään ajoneuvokäytössä elektronisiin laitteisiin mahdollisesti vaikuttavat sähkömagneettiset häiriöt, kytkeytyneiden häiriöiden siirtotiet sekä kytkeytyneiden häiriöiden muodot. Työssä käydään läpi lyhyesti tapoja joilla häiriön syntyä voidaan vähentää. Lisäksi työssä käydään läpi lyhyesti tapoja joilla häiriön vaikutusta voidaan pyrkiä vähentämään. Työssä esitellään laite, jonka mahdollisuuksia toimia taksin taksamittarina tutkitaan. Taksin taksamittarin tulee täyttää Euroopan Unionin alueella myynnissä ollessaan täyttää Euroopan Unionin asettama direktiivi ajoneuvoelektroniikalle, lisäksi laitteen tulee täyttää Euroopan Unionin mittalaitedirektiivin asettamat vaatimukset. Esitellyn laiteen häiriönsietoa testataan sähkökenttää vastaan Euroopan Unionin asettaman direktiivin mukaisesti.
Resumo:
Allergic diseases including food allergy and eczema in an infant in combination with the everyday activities of caring for a family will pose challenges to parents. Only fragments of these challenges are revealed to health care professionals. Families have varying mental, social and economic resources to help them care for an allergic infant, and all such resources are important in determining how families succeed in meeting these challenges and the quality of the infant’s care. This study evaluated the whole burden to the family caused by an infant's allergic disease during the first 24 months of life. As the primary caregiver during this period is usually the mother, her perspective was considered important. Ecocultural theory, which considers families as capable of modifying the positive and negative forces facing them, was taken as the frame of reference. Data were collected as part of an ongoing prospective mother-infant study, and the methods included severity scoring of atopic dermatitis, dietary records, health-related quality of life measurements and assessments of the use of health care services and medications for treating the infant’s eczema, food allergy and asthma. Interviews with mothers were analysed by deductive content analysis on the basis of ecocultural theory and the family empowerment model. The theme “Living an ordinary family life” guided the organization of family activities essential for treating the infant's food allergy and eczema. These activities were sources of both strain and support for the mothers, the allergy-related supporting factors being the mother’s own knowledge of the allergy, hopes for an improvement in the infant’s condition, social support and work. An infant’s food allergy at the age of one year caused considerable strain for the mother in cases where the introduction of new foods into the child’s diet was delayed. This delay was still causing the mother additional strain when the child was 24 months of age. The infants waking at night at the ages of 12 and 24 months because of itching related to eczema caused strain for the mothers. The infants’ health-related quality of life was impaired at ages of 6 and 12 months compared with healthy infants. The principal reasons for impairments were itching, scratching and sleep disturbances at 6 and 12 months and treatment difficulties at 6 months. Problems with getting to sleep were reported at all stages irrespective of eczema and were also present in healthy infants. The economic impact of the treatment of allergic diseases on families during the first 24 months was 131 EUR (2006 value) in cases of eczema and 525 EUR in cases of food allergy. From the societal perspective, the costs of food allergy were a median of 3183 EUR (range 628–11 560 EUR) and of eczema a median of 275 EUR (range 94–1306 EUR). These large variations in costs in food allergy and eczema indicate that disease varies greatly . In conclusion, food allergy and eczema cause extra activities and costs to families which arrange these disease-related activities in such a way that they support the leading family theme “Living an ordinary family life”. Health care professionals should consider this thematic character of family life and disease-related activities in order to ensure that new treatments are sustainable, meaningful and tailored to daily activities. In addition, those mothers who are experiencing difficulties with food allergic infants or infants with eczema should be recognized early and provided with individual encouragement and support from health clinics. In the light of the present results, early detection of symptoms and effective parental guidance can contribute to the well-being and health-related quality of life of the child and family.
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Among the main etiologies of secondary arterial hypertension figure out the tumorous affections of adrenal gland, located on cortex - primary aldosteronism (Conn’s syndrome) and Cushing’s syndrome - or at glandular medulla - pheocromocytoma. Although these tumors are at most benign the surgical resection is needed in order to eliminate the disturbances provided by them and to limit the mass growth, being curative in about 80-90% of the cases. In this paper some particularities above surgical treatment of these diseases will be focused emphasizing the pre-operative prepare of the patients and the currently preconized approach.
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Connectivity depends on rates of dispersal between communities. For marine soft-sediment communities continued small-scale dispersal as post-larvae and as adults can be equally important in maintaining community composition, as initial recruitment of substrate by pelagic larvae. In this thesis post-larval dispersal strategies of benthic invertebrates, as well as mechanisms by which communities are connected were investigated. Such knowledge on dispersal is scarce, due to the difficulties in actually measuring dispersal directly in nature, and dispersal has not previously been quantified in the Baltic Sea. Different trap-types were used underwater to capture dispersing invertebrates at different sites, while in parallel measuring waves and currents. Local community composition was found to change predictably under varying rates of dispersal and physical connectivity (waves and currents). This response was, however, dependent on dispersal-related traits of taxa. Actively dispersing taxa will be relatively better at maintaining their position, as they are not as dependent on hydrodynamic conditions for dispersal and will be less prone to be passively transported by currents. Taxa also dispersed in relative proportions that were distinctly different from resident community composition and a significant proportion (40 %) of taxa were found to lack a planktonic larval life-stage. Community assembly was re-started in a large-scale manipulative field experiment over one year across several sites, which revealed how patterns of community composition (α-, β- and λ-diversity) change depending on rates of dispersal. Results also demonstrated that in response to small-scale disturbance, initial recruitment was by nearby-dominant species after which other species arrived from successively further away. At later assembly time, the number of coexisting species increased beyond what was expected purely by local niche requirements (species sorting), transferring regional differences in community composition (β-diversity) to the local scale (α-diversity, mass effect). Findings of this thesis complement more theoretical studies in metacommunity ecology by demonstrating that understanding how and when individuals disperse relative to underlying environmental heterogeneity is key to interpreting how patterns of diversity change across different spatial scales. Such information from nature is critical when predicting responses to, for example, different types of disturbances or management actions in conservation.
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In order to study possible alterations of the skeleton which might play a role in the pathogenesis of the periodontitis of "cara inchada" in young cattle, ribs from 20 affected calves, 2 to 10 months old, were examined. Electrolytically decalcified longitudinal sections of the costochondral junction and cross sections through the corpus costae, stained with Haematoxylin-Eosin, were studied. In five calves, longitudinal sections of the proximal humerus were examined as well. The status of mineralization was checked by microradiograms. Systemic alteration of the skeleton due to disturbances of mineral metabolism could not be shown in any of the animals. In seven 2 to 4 months old calves, no bone changes were found. The reduced osteogenesis in six 3 to 5 months old calves and the reduced osteogenesis and diminished chondral growth in seven 5 to 10 months old calves are therefore a consequence of the disease. The results show that the development of the alveolar bone was not defective, so this cannot be a determinant factor for the development of the periodontitis of "cara inchada" in cattle.
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Tämä diplomityö on tehty osana Logproof-tutkimushanketta, joka keskittyy häiriöttömyyden hallintaan logistisissa monitoimijaverkostoissa. Työn tavoitteena on selvittää logistiikkaintensiivisten yritysten tarpeita kuljetusten häiriöiden analysoinnin ja hallinnan kehittämiseksi ja siten ennakoivan riskienhallinnan edistämiseksi. Asiakastarvetietoa on kerätty hyödyntäen puolistrukturoituja haastatteluja ja tietoa on analysoitu käyttäen hyväksi sisällönanalyysiä sekä tulkintataulukkoa. Kiinnostus kuljetusten häiriöitä ja niiden analysointia kohtaan on kasvamassa ja yrityksissä tiedostetaan hallintajärjestelmien ja analysoinnin tarve tulevaisuudessa. Kirjallisuuskatsauksen ja asiakastarpeiden kartoituksen avulla työssä on selvitetty yritysten nykytilaa kuljetusten häiriöiden hallinnan ja analysoinnin osalta ja tarkasteltu mahdollisia tulevaisuuden kehityssuuntia analysoimalla asiakkaiden näkyviä ja piileviä tarpeita. Työssä on edellisten lisäksi tarkasteltu, kuinka havaitut asiakastarpeet ovat sovitettavissa yhteen case-yrityksen, Oy Lars Krogius Ab:n, ARS (Analytic Rou-ting Solution) -palvelun ominaispiirteiden kanssa. Työ tarjoaa tarvetietoa palvelun tulevaisuuden kehitykselle.
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The relation between hyperglycemia and diabetic neuropathy has already been demonstrated in some studies. Among the theories proposed for its etiology the oxidative stress stands out. The performance of nitric oxide as a link between the metabolic and vascular neuropathogenic factors that triggers the diabetic neuropathy has already been put forward. This study aimed to assess the quantification and measurements of the cell body profile area (CBPA) of NADPH-diaphorase reactive (NADPH-dp) myenteric neurons of the jejunum of diabetic rats (induced by streptozotocin) supplemented with Ascorbic Acid (AA). These changes in the myenteric neurons seem to be related to the gastrointestinal disturbances observed in diabetes mellitus (DM). Twenty male Wistar rats (Rattus norvegicus) were distributed in 4 groups (n=5): controls (C), control supplemented (CS), diabetic (D), and diabetic suplemented (DS). DM was induced by estreptozotocin (50mg/kg body wt). One week after the induction and confirmation of the DM (glycemia exam), animals of the groups CS and DS received 50mg of AA three times a week by gavage. After 90 days of experiment, the animals were anesthetized with lethal thiopental dose (40mg/kg) and the collected jejunum processed for the histochemistry NADPH-diaphorase technique. Whole-mount preparations were obtained for quantitative and morphometric analysis of the myenteric neurons. A quantity of jejunum neurons in the Group D (96±7.5) was not different (P>0.05) from Group DS (116±8.08), C (92±9.7), and CS (81±5.4), but in Group DS the quantity was higher (P<0.05) than in Group C and CS. The CBPA of neurons from Group D (189.50±2.68µm²) and DS (195.92±3.75µm²) were lower (P<0.05) than from Group C (225.13±4.37µm²) and CS (210.23±3.15µm²). The streptozotocin-induced DM did not change the jejunum-ileum area, the jejunum myenteric plexus space organization and the density of NADPH-dp neurons. The 50g AA-supplementation, three times a week, during 90 days, did not decrease hyperglycemia; however, it had a neuroprotective effect on the myenteric neurons, minimizing the increase on the CBPA of NADPH-dp neurons and increasing the amount of NADPD-dp neurons.