1,243 research outputs found
Replicated evidence for aminoacylase 3 and nephrin gene variations to predict antihypertensive drug responses
Peer reviewe
Neutraalisuihkujen simuloiminen Wendelstein 7-X -stellaraattorissa
Stellarator fusion devices have seen a resurgence of interest in recent years, culminating in the building of the Wendelstein 7-X (W7-X) optimized stellarator in Germany. Compared to tokamaks, stellarators have the advantage of having no externally driven electric current.
However, their non-axisymmetric nature makes it difficult to achieve closed particle orbits. The neutral beam injection (NBI) heating system will be a significant source of fast ions in W7-X, hence predictive modeling of the fast ion confinement is required for machine protection and scenario development. In this thesis, methods for numerical simulations of NBI ions in W7-X are established. Stellarator-specific magnetic field and radial electric field modules were implemented for ASCOT5, the latest development version of the Monte-Carlo orbit-following code ASCOT. Neutral beam injection in the W7-X high mirror ratio scenario was simulated with the BBNBI code, and subsequently the beam ion distribution and wall loads with ASCOT4. The results imply that the global confinement percentage of fast particles is higher than average, and the power loads low, in this scenario, although high local wall loads were also observed.Stellaraattori-tyyppiset fuusiolaitteet ovat viime vuosina tuottaneet yhä lupaavampia tuloksia, yhtenä tärkeimmistä Wendelstein 7-X stellaraattorin hyvin menestynyt ensimmäinen koekamppanja.
Stellaraattorit ovat jatkuvatoimisia laitteita eivätkä vaadi ulkoisesti tuotettua plasmavirtaa, mutta niissä tarvitaan magneettikentän optimointia hiukkasten koossapidon varmistamiseksi. Erityisen vaarallisia ovat neutraalisuihkukuumennuksessa syntyvät nopeat ionit, joiden mallintaminen ennen kuumennuksen käyttöönottoa on tärkeää riskien kartoittamiseksi. Tässä työssä esittelemme menetelmiä neutraalisuihkujen mallinnukseen stellaraattoreissa. Stellaraattorien simuloimiseen vaadittavat magneetti- ja sähkökenttäominaisuudet lisättiin Monte Carlo-koodi ASCOT:n uusimpaan versioon. Neutraalisuihkujen toimintaa simuloitiin BBNBI-ohjelmalla, jonka jälkeen ionien ratoja seurattiin ASCOT4-ohjelmalla virtuaalisessa Wendelstein 7-X:ssä. Tulokset osoittivat, että nopeiden hiukkasten koossapito tutkituilla asetuksilla on kohtuullisen hyvä, mutta ionit saattavat paikallisesti aiheuttaa suuria seinäkuormia
Trends in Teenage Sexual Behavior and Births in Europe
Sexual and reproductive behavior, and outcomes of that behavior, are treated in thisarticle in the framework of sexual and reproductive health. The focus is on teenagers.European trends in sexual behavior and in fertility/births from the 1980s to the late1990s are presented.The transition in sexual initiation started first in the Nordic countries, then in manyWestern European and Central European countries and finally, one generation later,in Southern and Eastern Europe. The age of women at first sexual intercoursedecreased several years almost everywhere in Europe. Due to improvements in sexeducation and in the use of contraceptives, teenage birth rates have been declining,at the same time, around Europe.There is a serious need for sexual health prevention campaigns and related servicesin Europe. Work for improvement of sexual and reproductive health and rights canbe successful only in a society where there is openness and social tolerance onsexual issues
The IUCN Red List of Ecosystems: motivations, challenges, and applications
Abstract
In response to growing demand for ecosystem-level risk assessment in biodiversity conservation, and rapid proliferation of locally tailored protocols, the IUCN recently endorsed new Red List criteria as a global standard for ecosystem risk assessment. Four qualities were sought in the design of the IUCN criteria: generality; precision; realism; and simplicity. Drawing from extensive global consultation, we explore trade-offs among these qualities when dealing with key challenges, including ecosystem classification, measuring ecosystem dynamics, degradation and collapse, and setting decision thresholds to delimit ordinal categories of threat. Experience from countries with national lists of threatened ecosystems demonstrates well-balanced trade-offs in current and potential applications of Red Lists of Ecosystems in legislation, policy, environmental management and education. The IUCN Red List of Ecosystems should be judged by whether it achieves conservation ends and improves natural resource management, whether its limitations are outweighed by its benefits, and whether it performs better than alternative methods. Future development of the Red List of Ecosystems will benefit from the history of the Red List of Threatened Species which was trialed and adjusted iteratively over 50 years from rudimentary beginnings. We anticipate the Red List of Ecosystems will promote policy focus on conservation outcomes in situ across whole landscapes and seascapes
Sexual experiences of military conscripts at the end of the 1990s
The sexual socialization and sexual experiences of young men past their adolescence have been studied relatively little thus far. ln the present study, the subject was approached through surveys conducted in 1996 and 1998 in a number of garrisons. There were 984 male respondents in 1996 and 1220 in 1998. 20 years old on average. Both years, the response rate consisted of 98 percent of the conscripts selected for the study. The themes of the study were the sexual experience, number of partners and use of condoms among young men, and how these relate to the mens habits and values in general. Seventy-six percent of the men had engaged in sexual intercourse. One out of two had only one partner over the last year, and one out of four had more than one. For one out of three men. The most recent sexual itercourse occurred with a non-steady partner: Less than half of the men used a condom in their most recent sexual intercourse. The age for initiation into sexual intercourse and the number of partners were strongly correlated with whether the conscripts had secondary education and their use of intoxicants. Those who used more intoxicants, started engaging in sexual intercourse at a younger age and engaged into more relationships. Young men had steady relationships and acquired sexual experiences in accordance with their social skills and the choices the had made regarding their career
Teenagers' sexuality in Estonia and Finland in the 1990s
The present study assessed adolescent knowledge of sexual issues and sexual behavior in Estonia and Finland. The Estonian survey was conducted among students in the final grade of comprehensive school in March 1994, with a questionnaire translated trom the Finnish KISS-92 study. The Estonian sample comprised 532 boys and 548 girls 15.0 years old on average; part of the Finnish KISS group of 1992, covering 680 boys and 687 girls 15.8 years old on average, served for comparison. Significance of difference was tested. Estonian adolescents were found to have significantly less sexual experiences than their Finnish counterparts. At the same time quite a large proportion of the Estonian adolescents were attitudinally ready to start sexual intercourse. From this point of view, it is alarming that knowledge of sexual issues was poor among Estonian adolescents: only one out of ten respondents had good and about one- half had poor knowledge of sexual issues. A good level of knowledge was five times more common among Finnish boys compared to Estonian boys. Among girls the difference was eightfold, respectively
Tutkija ja poliitikko – voiko roolit yhdistää?
Otsikon antoi lehden toimitus. Lyhyt vastaus sen kysymykseen on, kyllä. Työurani on kestänyt nyt noin 18 vuotta. Ensimmäisen puoliskon siitä olin poliittisesti aktiivinen tutkija. Jälkimmäisen puoliskon olen ollut tutkimuksellisesti suuntautunut kansanedustaja. Kokemukseni perusteella uskallan sanoa, että totta kai yhdistäminen on mahdollista, usein jopa suotavaa
Impact of furnace dimensions on recovery boiler performance and cost
In this work designing and pricing of the recovery boiler were studied. The main goal was to find out how furnace screen heat transfer surface affects the recovery boiler price and performance. Two different boiler sizes were studied. Four different boilers were designed in both boiler sizes. One boiler was designed without furnace screen and three others with different size of furnace screens. The boilers were desinged so that they reached the same performances and were comparable.
The furnace screen is an effective heat transfer surface and by adding the furnace screen the furnace can be designed lower. Furnace height has a significant effect on the total price of the boiler. On the other hand, the reduced furnace height yields shorter flue gas residence time, which can lead to incomplete combustion resulting e.g. increased emissions.
Combustion air ratio and mixing of reactants with the air jets have a great effect on the combustion efficiency. In this study, the reduced residence time was compensated by the higher combustion air ratio by feeding more combustion air into the furnace. This way the effective mixing and the complete combustion were ensured.
In order to find out the required amount of combustion air for the complete combustion CFD simulations and field data analysis were made. The target was to find out the effect of the combustion air ratio and the residence time on the CO emissions. According to these results boilers with the different heights could be designed so that they achieve also the same CO emissions. The designed boilers were priced and compared. Only the changing boiler structures were taken into account in pricing, which was sorted out to heat transfer surfaces, high pressure pipes, steel structures, auxiliary equipment and civil/structural costs. The material, manufacturing and erection costs were studied. The heat transfer surfaces and boiler building had the most significant portions in the share of costs
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