9 resultados para 7140-301
em Helda - Digital Repository of University of Helsinki
Resumo:
The need for special education (SE) is increasing. The majority of those whose problems are due to neurodevelopmental disorders have no specific aetiology. The aim of this study was to evaluate the contribution of prenatal and perinatal factors and factors associated with growth and development to later need for full-time SE and to assess joint structural and volumetric brain alterations among subjects with unexplained, familial need for SE. A random sample of 900 subjects in full-time SE allocated into three levels of neurodevelopmental problems and 301 controls in mainstream education (ME) provided data on socioeconomic factors, pregnancy, delivery, growth, and development. Of those, 119 subjects belonging to a sibling-pair in full-time SE with unexplained aetiology and 43 controls in ME underwent brain magnetic resonance imaging (MRI). Analyses of structural brain alterations and midsagittal area and diameter measurements were made. Voxel-based morphometry (VBM) analysis provided detailed information on regional grey matter, white matter, and cerebrospinal fluid (CSF) volume differences. Father’s age ≥ 40 years, low birth weight, male sex, and lower socio-economic status all increased the probability of SE placement. At age 1 year, one standard deviation score decrease in height raised the probability of SE placement by 40% and in head circumference by 28%. At infancy, the gross motor milestones differentiated the children. From age 18 months, the fine motor milestones and those related to speech and social skills became more important. Brain MRI revealed no specific aetiology for subjects in SE. However, they had more often ≥ 3 abnormal findings in MRIs (thin corpus callosum and enlarged cerebral and cerebellar CSF spaces). In VBM, subjects in full-time SE had smaller global white matter, CSF, and total brain volumes than controls. Compared with controls, subjects with intellectual disabilities had regional volume alterations (greater grey matter volumes in the anterior cingulate cortex bilaterally, smaller grey matter volume in left thalamus and left cerebellar hemisphere, greater white matter volume in the left fronto-parietal region, and smaller white matter volumes bilaterally in the posterior limbs of the internal capsules). In conclusion, the epidemiological studies emphasized several factors that increased the probability of SE placement, useful as a framework for interventional studies. The global and regional brain MRI findings provide an interesting basis for future investigations of learning-related brain structures in young subjects with cognitive impairments or intellectual disabilities of unexplained, familial aetiology.
Resumo:
Most of the diseases affecting public health, like hypertension, are multifactorial by etiology. Hypertension is influenced by genetic, life style and environmental factors. Estimation of the influence of genes to the risk of essential hypertension varies from 30 to 50%. It is plausible that in most of the cases susceptibility to hypertension is determined by the action of more than one gene. Although the exact molecular mechanism underlying essential hypertension remains obscure, several monogenic forms of hypertension have been identified. Since common genetic variations may predict, not only to susceptibility to hypertension, but also response to antihypertensive drug therapy, pharmacogenetic approaches may provide useful markers in finding relations between candidate genes and phenotypes of hypertension. The aim of this study was to identify genetic mutations and polymorphisms contributing to human hypertension, and examine their relationships to intermediate phenotypes of hypertension, such as blood pressure (BP) responses to antihypertensive drugs or biochemical laboratory values. Two groups of patients were investigated in the present study. The first group was collected from the database of patients investigated in the Hypertension Outpatient Ward, Helsinki University Central Hospital, and consisted of 399 subjects considered to have essential hypertension. Frequncies of the mutant or variant alleles were compared with those in two reference groups, healthy blood donors (n = 301) and normotensive males (n = 175). The second group of subjects with hypertension was collected prospectively. The study subjects (n=313) underwent a protocol lasting eight months, including four one-month drug treatment periods with antihypertensive medications (thiazide diuretic, β-blocker, calcium channel antagonist, and an angiotensin II receptor antagonist). BP responses and laboratory values were related to polymorphims of several candidate genes of the renin-angiotensin system (RAS). In addition, two patients with typical features of Liddle’s syndrome were screened for mutations in kidney epithelial sodium channel (ENaC) subunits. Two novel mutations causing Liddle’s syndrome were identified. The first mutation identified located in the beta-subunit of ENaC and the second mutation found located in the gamma-subunit, constituting the first identified Liddle mutation locating in the extracellular domain. This mutation showed 2-fold increase in channel activity in vitro. Three gene variants, of which two are novel, were identified in ENaC subunits. The prevalence of the variants was three times higher in hypertensive patients (9%) than in reference groups (3%). The variant carriers had increased daily urinary potassium excretion rate in relation to their renin levels compared with controls suggesting increased ENaC activity, although in vitro they did not show increased channel activity. Of the common polymorphisms of the RAS studied, angiotensin II receptor type I (AGTR1) 1166 A/C polymorphism was associated with modest changes in RAS activity. Thus, patients homozygous for the C allele tended to have increased aldosterone and decreased renin levels. In vitro functional studies using transfected HEK293 cells provided additional evidence that the AGTR1 1166 C allele may be associated with increased expression of the AGTR1. Common polymorphisms of the alpha-adducin and the RAS genes did not significantly predict BP responses to one-month monotherapies with hydroclorothiazide, bisoprolol, amlodipin, or losartan. In conclusion, two novel mutations of ENaC subunits causing Liddle’s syndrome were identified. In addition, three common ENaC polymorphisms were shown to be associated with occurrence of essential hypertension, but their exact functional and clinical consequences remain to be explored. The AGTR1 1166 C allele may modify the endocrine phenotype of hypertensive patients, when present in homozygous form. Certain widely studied polymorphisms of the ACE, angiotensinogen, AGTR1 and alpha-adducin genes did not significantly affect responses to a thiazide, β-blocker, calcium channel antagonist, and angiotensin II receptor antagonist.
Resumo:
Agriculture is an economic activity that heavily relies on the availability of natural resources. Through its role in food production agriculture is a major factor affecting public welfare and health, and its indirect contribution to gross domestic product and employment is significant. Agriculture also contributes to numerous ecosystem services through management of rural areas. However, the environmental impact of agriculture is considerable and reaches far beyond the agroecosystems. The questions related to farming for food production are, thus, manifold and of great public concern. Improving environmental performance of agriculture and sustainability of food production, sustainabilizing food production, calls for application of wide range of expertise knowledge. This study falls within the field of agro-ecology, with interphases to food systems and sustainability research and exploits the methods typical of industrial ecology. The research in these fields extends from multidisciplinary to interdisciplinary and transdisciplinary, a holistic approach being the key tenet. The methods of industrial ecology have been applied extensively to explore the interaction between human economic activity and resource use. Specifically, the material flow approach (MFA) has established its position through application of systematic environmental and economic accounting statistics. However, very few studies have applied MFA specifically to agriculture. The MFA approach was used in this thesis in such a context in Finland. The focus of this study is the ecological sustainability of primary production. The aim was to explore the possibilities of assessing ecological sustainability of agriculture by using two different approaches. In the first approach the MFA-methods from industrial ecology were applied to agriculture, whereas the other is based on the food consumption scenarios. The two approaches were used in order to capture some of the impacts of dietary changes and of changes in production mode on the environment. The methods were applied at levels ranging from national to sector and local levels. Through the supply-demand approach, the viewpoint changed between that of food production to that of food consumption. The main data sources were official statistics complemented with published research results and expertise appraisals. MFA approach was used to define the system boundaries, to quantify the material flows and to construct eco-efficiency indicators for agriculture. The results were further elaborated for an input-output model that was used to analyse the food flux in Finland and to determine its relationship to the economy-wide physical and monetary flows. The methods based on food consumption scenarios were applied at regional and local level for assessing feasibility and environmental impacts of relocalising food production. The approach was also used for quantification and source allocation of greenhouse gas (GHG) emissions of primary production. GHG assessment provided, thus, a means of crosschecking the results obtained by using the two different approaches. MFA data as such or expressed as eco-efficiency indicators, are useful in describing the overall development. However, the data are not sufficiently detailed for identifying the hot spots of environmental sustainability. Eco-efficiency indicators should not be bluntly used in environmental assessment: the carrying capacity of the nature, the potential exhaustion of non-renewable natural resources and the possible rebound effect need also to be accounted for when striving towards improved eco-efficiency. The input-output model is suitable for nationwide economy analyses and it shows the distribution of monetary and material flows among the various sectors. Environmental impact can be captured only at a very general level in terms of total material requirement, gaseous emissions, energy consumption and agricultural land use. Improving environmental performance of food production requires more detailed and more local information. The approach based on food consumption scenarios can be applied at regional or local scales. Based on various diet options the method accounts for the feasibility of re-localising food production and environmental impacts of such re-localisation in terms of nutrient balances, gaseous emissions, agricultural energy consumption, agricultural land use and diversity of crop cultivation. The approach is applicable anywhere, but the calculation parameters need to be adjusted so as to comply with the specific circumstances. The food consumption scenario approach, thus, pays attention to the variability of production circumstances, and may provide some environmental information that is locally relevant. The approaches based on the input-output model and on food consumption scenarios represent small steps towards more holistic systemic thinking. However, neither one alone nor the two together provide sufficient information for sustainabilizing food production. Environmental performance of food production should be assessed together with the other criteria of sustainable food provisioning. This requires evaluation and integration of research results from many different disciplines in the context of a specified geographic area. Foodshed area that comprises both the rural hinterlands of food production and the population centres of food consumption is suggested to represent a suitable areal extent for such research. Finding a balance between the various aspects of sustainability is a matter of optimal trade-off. The balance cannot be universally determined, but the assessment methods and the actual measures depend on what the bottlenecks of sustainability are in the area concerned. These have to be agreed upon among the actors of the area
Resumo:
Tiivistelmä Maaraportin tavoitteena on luoda yleiskatsaus Italian kolmanteen sektoriin ja tutkimus kohdistuu erityisesti Pohjois-Italiassa sijaitsevan Veneton läänin kolmannen sektorin palvelutuotantoon. Raportissa tarkastellaan erityisesti kolmannen sektorin ja julkisen palvelutuotantosektorin sekä julkishallinnon toiminnallisia suhteita. Kolmannen sektorin mahdollisuuksia vastata maaseutualueiden palvelujen tarjonnan haasteisiin on pyritty analysoimaan. Italia on julkishallinnon ja kolmannen sektorin palvelutuotannon kannalta tarkasteltuna nykytilanteessa mielenkiintoinen testilaboratorio koko Euroopan mittakaavassa johtuen maan historiallisista, kulttuuri-sista, kieli- ja maantieteellisistä sekä itse väestöpohjan tarjoamista haasteista. Italiasta ei voida puhua yhden homogeenisen valtiokäsitteen alla, koska maa toimii kulttuurisista perinteistään johtuen kolmella eri nopeudella. Itse valtio käsitettäkin tulkitaan Italiassa monin eri tavoin pohjautuen ”valtiona” nähdyn organisaation käytännön funktioon sitoutuneena alueellisiin ja kulttuurisiin tekijöihin. Teollinen, dynaaminen yritysten varakas Pohjois-Italia henkilöityneenä Milanoon, hallinnon ja kulttuurin leimaama Keski-Italia kiteytyneenä ikuiseen kaupunkiin Roomaan ja Napolin alapuolinen Etelä-Italia, joka painii ”järjestelmässä sisällä olevan järjestelmänsä” kanssa eivät ole koskaan muodos-taneet oikeasti yhtenäistä Italian valtiota. Italiassa erillisinä itsehallinnollisina alueina toimivat lääneiksi luettavat Sisilia, Trentino Alto-Adige, Val di Aosta, Sardegna ja Friuli-Venezia Giulia, mikä lisää hallinnollista kirjavuutta. Viimeisten vuosien aikana Italian julkishallinto on ollut jatkuvassa transitiotilassa yrittäessään kohdata uudistumisen vaateita globalisoituvassa maailmassa. Italiassa on meneillään hidas siirtyminen liittovaltiomaiseen järjestelmään ja jopa syvempään paikallisuuteen. Massiivinen ja raskas julkishallintokoneisto neljällä eri tasolla (valtio - lääninhallinnolliset alueet - vahvat maakunnat - kunnat) on erittäin hankalasti modernisoitavissa, mutta poliittinen tahtotila on vaihtumassa klassista vahvaa keskushallintoa kannattavasta ajattelutavasta hyväksymään federalistisia, alueellisia hallintoratkaisuja. Italiassa on herätty havaitsemaan, että ongelmien ratkaisu täytyy viedä itse alueille ja niiden ihmisille, koska unilateraalinen keskushallinnointitapa ei enää vastaa monikerroksisiin, moniulotteisiin alueellisiin haasteisiin. Jokaisella alueella on erilaiset lähtökohdat ongelmien ratkaisuihin myös globalisoitumisen asettamissa yhteisissä haasteissa. Kolmannen sektorin asema arvostettuna italialaisten kansalaispalvelujen täydentäjänä ja tuottajana alkaa olla nykypäivää. Kolmannen sektorin elintärkeä osuus uusien palvelutarpeiden tunnistamisessa on jo yleisesti tunnustettu tosiasia Italiassa. Vapaaehtoisjärjestöt toimivat eturivissä kansalaisten arkipäivässä ja pystyvät näin kanavoimaan ensimmäisinä sosiaalista kehityskulkua ja kohottamaan esiin erilaisia marginaalistenkin ryhmien tarpeita sekä vastaamaan niihin. Kolmas sektori laajentaa, tuottaa ja paikkaa paikallista julkista palvelutuotantoa. Ratkaiseva askel lainsäädännölliseltä kannalta on ollut rahoitusvirtojen ohjaaminen kolmannen sektorin ns. ONLUS-organisaatioille ja ONLUS-statuksen perustaminen vuonna 1997. Italiassa on 60 231.214 asukasta (31.7.2009) ja se on hallinnollisesti jakaantuneena 8 100 kuntaan. Suomessa vastaavat luvut ovat 5 350 712 asukasta ja 348 kuntaa (11/2009). Maantieteelliseltä kooltaan Italia ei eroa 301 338 km2:n pinta-alallaan paljonkaan Suomesta (338 424 km2). Väestömäärän erojen vuoksi Italiassa on keskimäärin 199,9 asukasta neliökilometrillä ja Suomessa 17,1. Maiden välinen suora vertailu ei ollut mittakaavaerojen vuoksi järkevää. Kuntien hallinnollinen rooli on Italiassa painotukseltaan erilainen kuin Suomessa. Suomessa kuntien vastuulla oleva sosiaali-, terveydenhuolto- ja koulutoimi eivät ole samassa laajuudessa italialaisten kuntien vastuulla vaan näiden toimialojen vastuulliset tahot ovat läänit terveydenhoitopiireineen sekä maakuntahallinto koulupiirien osalta. Italialaisten kuntien vastuualueet voivat myös vaihdella mittavasti perustuslaissa määriteltyjen perustoimien lisäksi. Tutkimuksen kohteeksi on rajattu Koillis-Italiassa sijaitseva Veneton läänin alue, koska se on väkimäärältään lähes yhtä suuri kuin Suomi, 4 893 309 asukasta (31.3.2009). Kuntien lukumäärä on huimaava 581 kpl. Veneto on maantieteelliseltä alueeltaan pieni ja harvaan asuttua maaseutua on pinta-alasta melko niukasti. Pohjoisen osan vuoristoalueet karuine olosuhteineen muodostavat palvelutuotannollisesti haas-teellisen ympäristön, joka on verrattavissa suomalaisten maaseutualueiden tilanteeseen. Venetossa on omaksuttu Italian mittakaavassa innovatiivisia ratkaisuja julkishallinnon palvelutuotannon ja kolmannen sektorin toiminnan osalta. Veneton alue on luokiteltu maailman pienyritysintensiivisimmäksi alueeksi, mikä heijastuu myös alueen palvelutuotantoratkaisuissa. Raportti esittelee ensin Italian hallintoa, keskushallinnon, paikallishallinnon ja tutkimuksen asettelulle olennaisten kolmannen sektorin toimijoiden osalta. Tämä on välttämätöntä, sillä kolmannen sektorin toiminta on Italiassa hyvin pitkälle lainsäädännöllä ohjattua ja rajattua. Kolmannen sektorin käsitteistöä, toimijoita, järjestäytymistä ja sen toimintaa säätelevää lainsäädäntöä esitellään tarkemmin. Veneton läänin osalta kolmanteen sektoriin perehdytään sekä hallinnon että toimijakentän näkökulmia tulkiten. Raportin lopussa esitellään kolmannen sektorin palvelutuotantoon ja hallinnointiin liittyviä case-esimerkkitapauksia.
Resumo:
We study the energy current in a model of heat conduction, first considered in detail by Casher and Lebowitz. The model consists of a one-dimensional disordered harmonic chain of n i.i.d. random masses, connected to their nearest neighbors via identical springs, and coupled at the boundaries to Langevin heat baths, with respective temperatures T_1 and T_n. Let EJ_n be the steady-state energy current across the chain, averaged over the masses. We prove that EJ_n \sim (T_1 - T_n)n^{-3/2} in the limit n \to \infty, as has been conjectured by various authors over the time. The proof relies on a new explicit representation for the elements of the product of associated transfer matrices.
Resumo:
This contribution deals with social and political aspects affecting cultural life in Jalisco (Mexico), during the last forty years. It is, especially, a critical view on the regional deterioration of experimental music, analysing ethnic, religion, gender and other social components in one of the culturally foremost states of Mexico.
Resumo:
Gene mapping is a systematic search for genes that affect observable characteristics of an organism. In this thesis we offer computational tools to improve the efficiency of (disease) gene-mapping efforts. In the first part of the thesis we propose an efficient simulation procedure for generating realistic genetical data from isolated populations. Simulated data is useful for evaluating hypothesised gene-mapping study designs and computational analysis tools. As an example of such evaluation, we demonstrate how a population-based study design can be a powerful alternative to traditional family-based designs in association-based gene-mapping projects. In the second part of the thesis we consider a prioritisation of a (typically large) set of putative disease-associated genes acquired from an initial gene-mapping analysis. Prioritisation is necessary to be able to focus on the most promising candidates. We show how to harness the current biomedical knowledge for the prioritisation task by integrating various publicly available biological databases into a weighted biological graph. We then demonstrate how to find and evaluate connections between entities, such as genes and diseases, from this unified schema by graph mining techniques. Finally, in the last part of the thesis, we define the concept of reliable subgraph and the corresponding subgraph extraction problem. Reliable subgraphs concisely describe strong and independent connections between two given vertices in a random graph, and hence they are especially useful for visualising such connections. We propose novel algorithms for extracting reliable subgraphs from large random graphs. The efficiency and scalability of the proposed graph mining methods are backed by extensive experiments on real data. While our application focus is in genetics, the concepts and algorithms can be applied to other domains as well. We demonstrate this generality by considering coauthor graphs in addition to biological graphs in the experiments.
Resumo:
XVIII IUFRO World Congress, Ljubljana 1986.