997 resultados para Eurocódigo 8


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The monoterpene cyclic ether, cineole (l,8-cineole, I) also known as eucalyptol, is a component of many essential oils and is widely distributed in nature. It is extensively used in pharmaceutical preparations for external application and also as a nasal spray. It was reported earlier that cineole when administered to sheep may be largely oxidized in the system (Scheline 1978). However the mode of metabolism of cineole is not known. Hence the present study was undertaken to investigate the metabolic fate of this ubiquitous terpenoid following its administration to rats by gastric intubation.

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Tutkimuskohteenani on vuonna 1988 syntyneiden suomenkielisten suomalaisten nuorten historiakulttuuri ja historiatietoisuus. Tutkimustehtävä kiteytyi kolmeen pääkysymykseen: mitkä historian välittäjäkanavat vaikuttavat eniten nuorten käsityksiin menneisyydestä, millä tavoin ja kuinka usein nuoret törmäävät historiaan arkielämässään ja millaiset historialliset tapahtumat ovat nuorille merkityksellisiä. Tutkimusjoukko muodostui 1093 kahdeksasluokkalaisesta, jotka vastasivat lomakekyselyyn kevätlukukaudella 2003. Menetelmänä käytettiin ryväsotantaa. Kyselylomake sisälsi pääosin suljettuja kysymyksiä. Tutkimuksen metodit ovat pääosin kvantitatiivisia. Analyysissa käytettiin frekvenssilaskentaa, keskiarvojen vertailua sekä havainnollistuksena taulukoita ja pylväsdiagrammeja. Kvantitatiivisilla menetelmillä kartoitettiin yleiskuvaa nuorten historiakulttuurista sekä eroja tyttöjen ja poikien välillä. Kvalitatiivista tutkimusotetta käytettiin avointen kysymysten kohdalla sekä analysoitaessa historian välittäjäkanavia julkisten ja kansanomaisten - oman, perheen ja suvun sisäisten sekä suvun ulkopuolisten - historian esityksinä. Nuorten historiatietoisuutta muokkaa eniten kouluopetus, jota vahvistaa median ylläpitämä julkinen historiakulttuuri. Viikoittaisissa historian kohtaamisissa poikien historiakulttuuria leimasivat tyttöjä enemmän julkiset historianesitykset - sanomalehdet ja visuaalinen eläytyminen television kautta - sekä historialliset roolipelit. Tyttöjen viikoittaisessa historian kohtaamisessa nousi voimakkaasti esille oman, henkilökohtaisen ja suvun historian käsittely päiväkirjan kirjoittamisen, muistoesineiden ja valokuvien kautta.Tytöt käyttävätkin historiaa oman elämänhistoriansa jäsentämisen sekä tradition siirtämisen tarkoituksessa. Nimenomaan heidän kauttaan näyttää elävän vahvana suvun muisteluperinne. Vaikka nuoret kohtaavat kansanomaisia historianesityksiä enemmän kuin julkista historiakulttuuria, heidän historiatietoisuutensa keskittyy jälkimmäiseen. He mieltävät tärkeäksi historiaksi lähinnä kansallisen menneisyyden ja historiakulttuurin julkiset muodot. Kouluopetuksen vaikutus näkyi nuorten vahvana uskona kansalliseen kertomukseen. Nuoret näkevät erityisen tärkeäksi Suomen itsenäisyyden ja Suomen sodat 1939-45 voitettuina itsenäisyyskamppailuina. Mannerheimia arvostettiin Suomen historian tärkeimpänä samaistumiskohteena ja Suomen sotien merkitys kulminoitui suvun jäsenten kohtaloiden ja kansallisen julkisen historian limittymiseen. Historian reseptiossa jatkotutkimuksen aiheita voisivat olla maaseudulla ja kaupungissa elävien nuorten historiakulttuurien erojen sekä erilaisten historiakulttuuristen alaryhmien hahmottaminen. Empiiristä kartoitusta ja vertailevaa tutkimusta voisi tehdä myös eri ikäryhmien historiakulttuurien välillä.

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A blunt-nosed hypersonic missile mounted with a forward-facing cavity is a good alternative to reduce the stagnation heating rates. The effects of a forward-racing cavity on heat transfer and aerodynamic coefficients are addressed in this paper. Tests were carried out in hypersonic shock tunnel HST2, at a hypersonic Mach number of 8 using a 41 deg apex-angle blunt cone. The aerodynamic forces on the test model with and without a forward-facing cavity at various angles of attack are measured by using an internally mountable accelerometer force balance system. Heat flux measurements have been carried out on the test model with and without a forward-facing cavity of the entire surface at zero degree angle of attack with platinum sensors. A numerical simulation was also carried out using the computational fluid dynamics code (CFX-Ansys 5.7). An important result of this study is that the smaller cavity diameter has the highest lift-to-drag ratio, whereas the medium cavity has the highest heat flux reduction. Theshock structure around the test model has also been visualized using the Schlieren flow visualization technique. The visualized shock structure and the measured aerodynamic forces on the missile-shaped body with cavity configurations agree well with the axisymmetric numerical simulations.

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The electron and hole mobilities of octathio[8]circulene (sulflower) crystal have been calculated using quantum chemical methods, with accurate determination of reorganization energies and the rate of charge transfer, the key parameters controlling the charge carriers conductance. We find this molecular crystal to be an excellent conductor with large mobilities for both the charge carriers. Moreover, the hole mobility is found to be slightly larger than the electron mobility. Such an ambipolar organic crystal with substantial carrier mobilities shows possibilities of sophisticated device fabrication in advanced electronics.

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C17H19N302, monoclinic, P21, a = 5.382 (1), b = 17.534(4), c = 8.198(1)/L ,8 = 100.46(1) °, Z= 2, d,, = 1.323, dc= 1.299 Mg m-3, F(000) = 316, /~(Cu .Ka) = 0.618 mm -1. R = 0.052 for 1284 significant reflections. The proline-containing cispeptide unit which forms part of a six-membered ring deviates from perfect planarity. The torsion angle about the peptide bond is 3.0 (5) ° and the peptide bond length is 1.313 (5)A. The conformation of the proline ring is Cs-Cf~-endo. The crystal structure is stabilized by C-H... O interactions.

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[Excerpt] These comments are in response to the “Request for Information Concerning Labor Rights in Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua and their Laws Governing Exploitative Child Labor” published at 68 Fed. Reg. 19580 (April 21, 2003). This Request for Information was issued pursuant to Section 2102(c)(8) and (9) of the Trade Act of 2002, Pub. L. 107-210, which requires the President, with respect to any proposed trade agreement, to submit to Congress a “meaningful labor rights report” and a “report describing the extent to which the country or countries that are parties to the agreement have in effect laws governing exploitative child labor.”

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C18H2204, orthorhombic, P212~21, a = 7.343 (4), b = 11.251 (4), c = 19.357 (4)A, Z = 4, Dr, ' = 1.20, D e = 1.254 g cm -3, F(000) = 648, p(MoKa) = 0.94 cm -~. X-ray intensity data were collected on a Nonius CAD-4 diffractometer and the structure was solved by direct methods. Full-matrix least-squares refinement gave R = 0.052 (R w = 0.045) for 1053 observed reflections. The stereochemical configuration at C(2) has been shown to be 2-exo-methyl-2-endo-(2,6-dimethoxyphenyl), i.e. (3) in contrast to the structure (2) assigned earlier based on its ~H NMR data.

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- Purpose To examine the change in corneal thickness and posterior curvature following 8 hours of miniscleral contact lens wear. - Methods Scheimpflug imaging (Pentacam HR, Oculus) was captured before, and immediately following, 8 hours of miniscleral contact lens wear for 15 young (mean age 22 ± 3 years), healthy participants with normal corneae. Natural diurnal variations were considered by measuring baseline corneal changes obtained on a separate control day without contact lens wear. - Results Over the central 6 mm of the cornea, a small, but highly statistically significant amount of edema was observed following 8 hours of miniscleral lens wear, after accounting for normal diurnal fluctuations (mean ± standard deviation percentage swelling 1.70 ± 0.98%, p < 0.0001). Posterior corneal topography remained stable following lens wear (-0.01 ± 0.07 mm steepening over the central 6 mm, p = 0.60). The magnitude of posterior corneal topographical changes following lens wear did not correlate with the extent of lens-related corneal edema (r = -0.16, p = 0.57). Similarly, the initial central corneal vault (maximum post-lens tear layer depth) was not associated with corneal swelling following lens removal (r = 0.27, p = 0.33). - Conclusions While a small amount of corneal swelling was induced following 8 hours of miniscleral lens wear (on average <2%), modern high Dk miniscleral contact lenses that vault the cornea do not induce clinically significant corneal edema or hypoxic related posterior corneal curvature changes during short-term wear. Longer-term studies of compromised eyes (e.g. corneal ectasia) are still required to inform the optimum lens and fitting characteristics for safe scleral lens wear to minimize corneal hypoxia.

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Bovine serum albumin conjugates of two trinucleotides, dpTpTpA and dTpTpAp, were prepared by linking the trinucleotides through their end phosphates by the ‘carbodiimide method’. Antibodies were raised in rabbits by injecting the trinucleotide-bovine serum albumin conjugates. Analysis by double diffusion in agar gel, quantitative precipitin reaction and its inhibition by haptens showed clearly the presence of antibodies specific to the whole trinucleotide molecule. The titre of antibodies obtained by the trinucleotide-rabbit serum albumin conjugates with their respective antisera was approximately the same, indicating that linking the trinucleotide through either 5′ or 3′ phosphate does not have an appreciable effect on the titre of antibodies. The results also demonstrate that the nucleotide(s) away from the carrier protein is more immunodominant than the one linked directly to the protein.

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Matrix metalloproteinase (MMP) -8, collagenase-2, is a key mediator of irreversible tissue destruction in chronic periodontitis and detectable in gingival crevicular fluid (GCF). MMP-8 mostly originates from neutrophil leukocytes, the first line of defence cells which exist abundantly in GCF, especially in inflammation. MMP-8 is capable of degrading almost all extra-cellular matrix and basement membrane components and is especially efficient against type I collagen. Thus the expression of MMP-8 in GCF could be valuable in monitoring the activity of periodontitis and possibly offers a diagnostic means to predict progression of periodontitis. In this study the value of MMP-8 detection from GCF in monitoring of periodontal health and disease was evaluated with special reference to its ability to differentiate periodontal health and different disease states of the periodontium and to recognise the progression of periodontitis, i.e. active sites. For chair-side detection of MMP-8 from the GCF or peri-implant sulcus fluid (PISF) samples, a dip-stick test based on immunochromatography involving two monoclonal antibodies was developed. The immunoassay for the detection of MMP-8 from GCF was found to be more suitable for monitoring of periodontitis than detection of GCF elastase concentration or activity. Periodontally healthy subjects and individuals suffering of gingivitis or of periodontitis could be differentiated by means of GCF MMP-8 levels and dipstick testing when the positive threshold value of the MMP-8 chair-side test was set at 1000 µg/l. MMP-8 dipstick test results from periodontally healthy and from subjects with gingivitis were mainly negative while periodontitis patients sites with deep pockets ( 5 mm) and which were bleeding on probing were most often test positive. Periodontitis patients GCF MMP-8 levels decreased with hygiene phase periodontal treatment (scaling and root planing, SRP) and even reduced during the three month maintenance phase. A decrease in GCF MMP-8 levels could be monitored with the MMP-8 test. Agreement between the test stick and the quantitative assay was very good (κ = 0.81) and the test provided a baseline sensitivity of 0.83 and specificity of 0.96. During the 12-month longitudinal maintenance phase, periodontitis patients progressing sites (sites with an increase in attachment loss ≥ 2 mm during the maintenance phase) had elevated GCF MMP-8 levels compared with stable sites. General mean MMP-8 concentrations in smokers (S) sites were lower than in non-smokers (NS) sites but in progressing S and NS sites concentrations were at an equal level. Sites with exceptionally and repeatedly elevated MMP-8 concentrations during the maintenance phase were clustered in smoking patients with poor response to SRP (refractory patients). These sites especially were identified by the MMP-8 test. Subgingival plaque samples from periodontitis patients deep periodontal pockets were examined by polymerase chain reaction (PCR) to find out if periodontal lesions may serve as a niche for Chlamydia pneumoniae. Findings were compared with the clinical periodontal parameters and GCF MMP-8 levels to determine the correlation with periodontal status. Traces of C. pneumoniae were identified from one periodontitis patient s pooled subgingival plaque sample by means of PCR. After periodontal treatment (SRP) the sample was negative for C. pneumoniae. Clinical parameters or biomarkers (MMP-8) of the patient with the positive C. pneumoniae finding did not differ from other study patients. In this study it was concluded that MMP-8 concentrations in GCF of sites from periodontally healthy individuals, subjects with gingivitis or with periodontitis are at different levels. The cut-off value of the developed MMP-8 test is at an optimal level to differentiate between these conditions and can possibly be utilised in identification of individuals at the risk of the transition of gingivitis to periodontitis. In periodontitis patients, repeatedly elevated GCF MMP-8 concentrations may indicate sites at risk of progression of periodontitis as well as patients with poor response to conventional periodontal treatment (SRP). This can be monitored by MMP-8 testing. Despite the lower mean GCF MMP-8 concentrations in smokers, a fraction of smokers sites expressed very high MMP-8 concentrations together with enhanced periodontal activity and could be identified with MMP-8 specific chair-side test. Deep periodontal lesions may be niches for non-periodontopathogenic micro-organisms with systemic effects like C. pneumoniae and possibly play a role in the transmission from one subject to another.

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Pyrolysis of (eta(5)-C5Me5WH3)B4H8, 1, in the presence of excess BHCl2 center dot SMe2 in toluene at 100 degrees C led to the isolation of (eta(5)-C5Me5W)(2)B5H9, 2, and B-Cl inserted (eta(5)-C5Me5W)(2)B5H8Cl, 3, and (eta(5)-C5Me5W)(2)B5H7Cl2, (four isomers). All the Chlorinated tungstaboranes were isolated as red and air and moisture sensitive solids. These new compounds have been characterized in solution by H-1, B-11, C-13 NMR, and the structural types were unequivocally established by crystallographic analysis of compounds 3, 4, and 7. Density functional theory (DFT) calculations were carded out on the model molecules of 3-7 to elucidate the actual electronic structures of these chlorinated species. On grounds of DFT calculations we demonstrated the role of transition metals, bridging hydrogens, and the effect of electrophilic substitution of hydrogens at B-H vertices of metallaborane structures.