1000 resultados para Pre-orifice nozzle


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OBJECTIVE: This pilot experimental study tested the feasibility and intended effect of an educational intervention for parents to help them assist their adolescent child with chronic illness (CI) in becoming autonomous. METHODS: A two-phase pre-post pilot intervention study targeting parents of adolescents with CI was conducted. Parents were allocated to group 1 and 2 and received the four-module intervention consecutively. Intended effect was measured through online questionnaires for parents and adolescents before, at 2 months after, and at 4-6 months after the intervention. Feasibility was assessed through an evaluation questionnaire for parents. RESULTS: The most useful considered modules concerned the future of the adolescent and parents and social life. The most valued aspect was to exchange with other parents going through similar problems and receiving a new outlook on their relationship with their child. For parents, improvement trends appeared for shared management, parent protection, and self-efficacy, and worsening trends appeared for coping skills, parental perception of child vulnerability, and parental stress. For adolescents, improvement trends appeared for self-efficacy and parental bonding and worsening trends appeared for shared management and coping skills. CONCLUSION: Parents could benefit from peer-to-peer support and education as they support the needed autonomy development of their child. Future studies should test an online platform for parents to find peer support at all times and places.

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Suojakaasupakkaaminen (MAP) on yleistynyt viime aikoina, koska sen avulla voidaan säilöä tuoreita tai vähän käsiteltyjä elintarvikkeita pidempään. Suurin syy hyllyiän pidentymiseen on hiilidioksidin aiheuttama mikrobien kasvun hidastuminen. Toisaalta huolena on patogeenisten mikrobien lisääntyminen anaerobisissa olosuhteissa. Pidempi säilyvyys voidaan saavuttaa myös käyttämällä vähemmän lisä- ja säilöntäaineita. Samalla suojakaasupakkaaminen kuitenkin vähentää myös pilaantuneiden tuotteiden määrää. Eniten suojakaasua käytetään lihan pakkaamisessa. Suojakaasupakkaamisessa elintarvikepakkaukseen syötetään normaalista huoneilmasta poikkeava kaasuseos. Pääasiassa kaasuseos koostuu hiilidioksidista, hapesta ja typestä. Lisäksi voidaan käyttää pieniä määriä hiilimonoksidia, argonia ja rikkidioksidia. Kaasuseoksen koostumus määräytyy elintarvikkeiden ominaisuuksien ja vaatimusten perusteella. Halutun kaasukoostumuksen tulee säilyä pakkauksessa muutamasta päivästä muutamaan kuukauteen riippuen elintarvikkeesta. Siksi tärkein pakkaukselta vaadittava ominaisuus on riittävä kaasutiiveys ja erityisesti hapenläpäisevyys. Koska suurin osa suojakaasupakkauksista on tällä hetkellä muovisia, tutkittiin kokeellisessa osiossa kartonkipakkausten tiiveysominaisuuksia. Kokeet tehtiin vertailemalla erilaisten vuoka- ja kansimateriaalien vaikutusta pakkausten tiiveyteen. Vuokien onnistuminen oli suurin yksittäinen tuloksiin vaikuttanut tekijä. Epäonnistuneen vuoan vaikutukset näkyivät myös saumauksessa, koska saumaustyökalun ja vuoan piti sopia yhteen. Lisäksi näkymättömät mikroreiät hankaloittivat todellisten vuotokohtien paikallistamista. Vuototestausten perusteella materiaaleille löydettiin kuitenkin viitteelliset optimiparametrit. Tärkein saumauksessa vaikuttanut tekijä oli sopivan saumauslämpötilan valinta. Prässättyjen vuokien laatu oli epätasainen. Siksi erityisesti rinnakkaisten kansitus- ja hapenläpäisymittausten väliset erot olivat merkitseviä. Lisäksi prässäys laski materiaalien hapenläpäisyominaisuuksia. Yksittäisten vuokien tiiveysominaisuudet täyttivät kuitenkin kaupallisille kaasupakkauksille asetetut vaatimukset. Vesihöyrynläpäisevyydessä materiaalin vesihöyrynläpäisy oli merkittävämpää kuin vesihöyryn kulkeutuminen vuotokohtien tai epäonnistuneiden saumojen kautta.

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Tässä diplomityössä suunniteltiin ja rakennettiin kaasuturbiinin kaasusuuttimien virtausmittauslaitteisto. Suuttimien epätasainen toiminta kasvattaa kaasuturbiinin poistolämpötilahajontaa. Virtausmittauksien perusteella voidaan määrittää suuttimien efektiivinen virtauspoikkipinta-ala. Suuttimien asennusjärjestys opti-moidaan suuttimien välisten pinta-alaerojen mukaisesti, jolloin polttoainevirtaus polttokammioihin on mahdollisimman tasainen ja poistolämpötilahajonta pienenee. Kaasuturbiinin MS6001 esittelyssä keskityttiin tärkeimpiin komponentteihin sekä polttoainesuuttimien testauksen kannalta oleellisiin osiin ja niiden toimintaan. Teoriaosuudessa tarkasteltiin tilavuusvirran sekä suutinvirtauksen laskennassa käytettäviä yhtälöitä. Mittalaitteiston suunnittelu ja toteutus olivat tämän työn laajin osa-alue. Laitteiston keskeiset osat ovat kuristuselin ja suutintestausosa. Kuristuselintyypiksi valittiin rengaskammiollinen kuristuslaippa, joka suun-niteltiin standardin SFS-EN ISO 5167:2003 mukaisesti. Standardissa annettujen yhtälöiden antamia tuloksia verrattiin numeerisella virtauslaskentamallilla lasket-tuihin tuloksiin. Suutinrunkojen ja -kärkien mittauksien suunnittelussa sovellettiin samaa standardia sekä numeerista virtauslaskentaa optimaalisen sijainnin löytämiseksi paineyhteelle. Mittauksissa syntyvien epävarmuuksien arviointiin kiinnitettiin erityistä huomiota. Kokeellisessa osuudessa mitattiin yhden kunnostetun suuttimen, käytetyn suut-timen ja suutinrungon virtausta. Tuloksien perusteella laskettiin efektiiviset pinta-alat, joita verrattiin turbiinivalmistajan ilmoittamiin pinta-aloihin. Lopuksi arvioitiin mittaustulosten perusteella laitteiston toimivuutta. Virhe-arvioinnin ja mittaustulosten perusteella laadittiin teknisiä parannusehdotuksia suutintestauslaitteiston luotettavan toiminnan varmistamiseksi.

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The purpose of this study was to investigate different laser cutting nozzles, nozzle flows and possibilities to improve nozzle flow. Another goal was to design new nozzle configuration in which laser cutting would succeed with better cutting speed and smaller gas consumption. Nozzles and nozzle flows were studied with various methods. Computational fluid dynamics was used to calculate old, convergent nozzles and new convergent-divergent nozzles. Measurement apparatus was used to measure both nozzle types. In cutting tests different materials were cut with new nozzles. With the use of design convergent-divergent nozzles 25 % better cutting speed and 33 % smaller gas consumption were achieved when cutting quality was good. Computational fluid dynamics was also discovered to be useful aid in nozzle design.

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OBJECTIVE: This study aimed to assess the long-term outcome of functional endoscopic sinus surgery for Samter's triad patients using an objective visual analogue scale and nasal endoscopy. METHOD: Using a retrospective database, 33 Samter's triad patients who underwent functional endoscopic sinus surgery were evaluated pre- and post-operatively between 1987 and 2007 in Hospital of La Chaux-de-Fonds, Switzerland. RESULTS: A total of 33 patients participated in the study, and the mean follow-up period was 11.6 years (range 1.2-20 years). Patients were divided into two groups based on visual analogue scale scores of the five parameters with the greatest difference in intensity of symptoms between the beginning and end of follow up. Group 1 included patients with a mean visual analogue scale score of 6 and below at the end of follow up and group 2 included patients with a mean visual analogue scale score of more than 6. The only statistically significant difference noted between the two groups was the endonasal findings: stage III-IV polyposis was present in 1 out of 24 patients (4 per cent) in group 1 and in 5 out of 9 patients (56 per cent) in group 2. CONCLUSION: The results of our study indicate that functional endoscopic sinus surgery helps stabilise disease progression. Stage III-IV polyposis had a significant adverse effect on long-term outcome.

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En este trabajo se presenta la interpretaciónpor métodos geofísicos combinados de un sector del contacto entre el Pre-Pirineo y la La zona objeto del presente estudio se halla a Depresión Central Catalana...

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Striatal adenosine A2A receptors (A2ARs) are highly expressed in medium spiny neurons (MSNs) of the indirect efferent pathway, where they heteromerize with dopamine D2 receptors (D2Rs). A2ARs are also localized presynaptically in cortico-striatal glutamatergic terminals contacting MSNs of the direct efferent pathway, where they heteromerize with adenosine A1 receptors (A1Rs). It has been hypothesized that postsynaptic A2AR antagonists should be useful in Parkinson's disease, while presynaptic A2AR antagonists could be beneficial in dyskinetic disorders, such as Huntington's disease, obsessive-compulsive disorders and drug addiction. The aim or this work was to determine whether selective A2AR antagonists may be subdivided according to a preferential pre- versus postsynaptic mechanism of action. The potency at blocking the motor output and striatal glutamate release induced by cortical electrical stimulation and the potency at inducing locomotor activation were used as in vivo measures of pre- and postsynaptic activities, respectively. SCH-442416 and KW-6002 showed a significant preferential pre- and postsynaptic profile, respectively, while the other tested compounds (MSX-2, SCH-420814, ZM-241385 and SCH-58261) showed no clear preference. Radioligand-binding experiments were performed in cells expressing A2AR-D2R and A1R-A2AR heteromers to determine possible differences in the affinity of these compounds for different A2AR heteromers. Heteromerization played a key role in the presynaptic profile of SCH-442416, since it bound with much less affinity to A2AR when co-expressed with D2R than with A1R. KW-6002 showed the best relative affinity for A2AR co-expressed with D2R than co-expressed with A1R, which can at least partially explain the postsynaptic profile of this compound. Also, the in vitro pharmacological profile of MSX-2, SCH-420814, ZM-241385 and SCH-58261 was is in accordance with their mixed pre- and postsynaptic profile. On the basis of their preferential pre- versus postsynaptic actions, SCH-442416 and KW-6002 may be used as lead compounds to obtain more effective antidyskinetic and antiparkinsonian compounds, respectively.

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An increased understanding of intraspecific seed packaging (i.e. seed size/number strategy) variation across different environments may improve current knowledge of the ecological forces that drive seed evolution in plants. In particular, pre-dispersal seed predation may influence seed packaging strategies, triggering a reduction of the resources allocated to undamaged seeds within the preyed fruits. Assessing plant reactions to pre-dispersal seed predation is crucial to a better understanding of predation effects, but the response of plants to arthropod attacks remains unexplored. We have assessed the effect of cone predation on the size and viability of undamaged seeds in populations of Juniperus thurifera with contrasting seed packaging strategies, namely, North African populations with single-large-seeded cones and South European populations with multi-small-seeded cones. Our results show that the incidence of predation was lower on the single-large-seeded African cones than on the multi-small-seeded European ones. Seeds from non-preyed cones were also larger and had a higher germination success than uneaten seeds from preyed cones, but only in populations with multi-seeded cones and in cones attacked by Trisetacus sp., suggesting a differential plastic response to predation. It is possible that pre-dispersal seed predation has been a strong selective pressure in European populations with high cone predation rates, being a process which maintains multi-small-seeded cones and empty seeds as a strategy to save some seeds from predation. Conversely, pre-dispersal predation might not have a strong effect in the African populations with single-large-seeded cones characterized by seed germination and filling rates higher than those in the European populations. Our results indicate that differences in pre-dispersal seed predators and predation levels may affect both selection on and intraspecific variation in seed packaging.

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(ENGLISH VERSION BELOW) En 1780, le médecin Jean-André Venel fonde à Orbe, dans le canton de Vaud, le premier institut orthopédique connu dans le monde, proposant une version clinique d'un savoir-faire médical ancestral. A travers des sources qui réactualisent les travaux consacrés à Venel, cet article retrace les origines de son institution et de sa pensée médicale, dans un contexte de production et de diffusion d'un savoir particulier en termes de technique du corps et de médecine de l'enfant. Revisitant la figure légendaire - ou mythique ? - de ce que l'histoire de la médecine a retenu comme étant le « père de l'orthopédie », l'article s'interroge par la même occasion sur les conditions d'émergence d'une spécialité médicale au sortir de l'Ancien Régime, et de son impact dans les premières décennies du XIXe siècle. In 1780, the physician Jean-André Venel creates in Orbe (canton of Vaud) the first orthopedic institute of the world, offering a clinical version of an ancient medical savoir-faire. By using sources that enable us to update the scholarship on Venel, this article traces the origins of his institute and of his medical thought, in the context of the production and diffusion of a specialized knowledge on the body and on children. With this new perspective on the legendary, if not mythical, figure, whom the history of medicine has canonized as the "father of orthopedia", this article also examines the conditions of emergence of a medical specialization at the end of the Ancien Régime and its impact in the first decades of the nineteenth century.

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The adult dentate gyrus produces new neurons that morphologically and functionally integrate into the hippocampal network. In the adult brain, most excitatory synapses are ensheathed by astrocytic perisynaptic processes that regulate synaptic structure and function. However, these processes are formed during embryonic or early postnatal development and it is unknown whether astrocytes can also ensheathe synapses of neurons born during adulthood and, if so, whether they play a role in their synaptic transmission. Here, we used a combination of serial-section immuno-electron microscopy, confocal microscopy, and electrophysiology to examine the formation of perisynaptic processes on adult-born neurons. We found that the afferent and efferent synapses of newborn neurons are ensheathed by astrocytic processes, irrespective of the age of the neurons or the size of their synapses. The quantification of gliogenesis and the distribution of astrocytic processes on synapses formed by adult-born neurons suggest that the majority of these processes are recruited from pre-existing astrocytes. Furthermore, the inhibition of astrocytic glutamate re-uptake significantly reduced postsynaptic currents and increased paired-pulse facilitation in adult-born neurons, suggesting that perisynaptic processes modulate synaptic transmission on these cells. Finally, some processes were found intercalated between newly formed dendritic spines and potential presynaptic partners, suggesting that they may also play a structural role in the connectivity of new spines. Together, these results indicate that pre-existing astrocytes remodel their processes to ensheathe synapses of adult-born neurons and participate to the functional and structural integration of these cells into the hippocampal network.

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AIMS: Smoking cessation has been suggested to increase the short-term risk of type 2 diabetes mellitus (T2DM). This study aimed at assessing the association between smoking cessation and incidence of T2DM and impaired fasting glucose (IFG). METHODS: Data from participants in the CoLaus study, Switzerland, aged 35-75 at baseline and followed for 5.5years were used. Participants were classified as smokers, recent (≤5years), long-term (>5years) quitters, and non-smokers at baseline. Outcomes were IFG (fasting serum glucose (FSG) 5.6-6.99mmol/l) and T2DM (FSG ≥7.0mmol/l and/or treatment) at follow up. RESULTS: 3,166 participants (63% women) had normal baseline FSG, of whom 26.7% were smokers, 6.5% recent quitters, and 23.5% long-term quitters. During follow-up 1,311 participants (41.4%) developed IFG (33.6% women, 54.7% men) and 47 (1.5%) developed T2DM (1.1% women, 2.1% men). Former smokers did not have statistically significant increased odds of IFG compared with smokers after adjustment for age, education, physical activity, hypercholesterolemia, hypertension and alcohol intake, with OR of 1.29 [95% confidence interval 0.94-1.76] for recent quitters and 1.03 [0.84-1.27] for long-term quitters. Former smokers did not have significant increased odds of T2DM compared with smokers with multivariable-adjusted OR of 1.53 [0.58-4.00] for recent quitters and 0.64 [0.27-1.48] for long-term quitters. Adjustment for body-mass index and waist circumference attenuated the association between recent quitting and IFG (OR 1.07 [0.78-1.48]) and T2DM (OR 1.28 [0.48-3.40]. CONCLUSION: In this middle-aged population, smoking cessation was not associated with an increased risk of IFG or T2DM.