993 resultados para STD-RMN


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In a continuing investigation for potentially bioactive natural products, flavonoids were isolated from Lonchocarpus araripensis (Leguminoseae) and identified as 3-methoxy-6-O-prenyl-6'',6''-dimethylchromene-[7,8,2'',3'']-flavone (1), 3,6-dimethoxy-6'',6''-dimethylchromene-[7,8,2'',3'']-flavone (2) and 3,5,8-trimethoxy-[6,7,2",3"]-furanoflavone (3). This is the first time compound 3 has been described. Compound 2 has been previously isolated from roots while this is the first time 1 is reported in this species. Complete NMR assignments are given for1 ,2 and 3 together with the determination of conformation for 1.

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The aim of this paper was to present a simple and fast way of simulating Nuclear Magnetic Resonance signals using the Bloch equations. These phenomenological equations describe the classical behavior of macroscopic magnetization and are easily simulated using rotation matrices. Many NMR pulse sequences can be simulated with this formalism, allowing a quantitative description of the influence of many experimental parameters. Finally, the paper presents simulations of conventional sequences such as Single Pulse, Inversion Recovery, Spin Echo and CPMG.

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In this work, proton NMR relaxometry was used to measure the behavior of spin-lattice relaxation time with T1H as the time constant, and also of spin-spin relaxation time with the time constant T2H. These relaxometry parameters were determined to better understand the changes in the main structures present in commercial and in nature forms of origanum. The T1H relaxation data showed that the structures which had higher molecular mass were more sensitive to degradation with increased temperature treatment. According to the values of the T2H parameter, up to 150 degrees no significant change in the mobility and organization of water was observed. These data infer that the ideal cooking temperature and tea preparation mode for this herb should be around 100 degrees for the sample not to lose its characteristics. Also, it is not advisable to cook this herb at higher than 150 degrees but better to consume it at room temperature, especially give commercial herb has already been dehydrated.

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Os deslocamentos químicos de RMN 13C de carbonos a , b , g e d de 17 conjuntos de haletos (F, Cl Br e I) alifáticos, inclusive compostos mono, bi e tricíclicos, podem ser reproduzidos por uma equação linear de duas constantes e duas variáveis do tipo : d R-X = A*d R-X1 + B*d R-X2 onde A e B são constantes obtidas por regressão multilinear a partir de deslocamentos químicos de 13C; d R-X, o deslocamento químico de 13C do composto com halogênio (R-X); d R-X1 e d R-X2 deslocamentos químicos de outros haletos. Para brometos (R-X) alifáticos a melhor correlação foi obtida com os dados de fluoretos (R-X1) e iodetos (R-X2) com R2 de 0,9989 e desvio médio absoluto (DM) de 0,39ppm. Para cloretos (R-X) a melhor correlação foi com dados de brometos (R-X1) e iodetos (R-X2) com R2 de 0,9960 e DM de 0,76ppm. Para fluoretos (R-X) a melhor correlação foi com brometos (R-X1) e iodetos (R-X2) com R2 de 0,9977 e DM de 1,10ppm e para iodetos (R-X) foi com fluoretos (R-X1) e brometos (R-X2) com R2 de 0,9972 e desvio médio absoluto de 0,60 ppm.

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kuv., 14 x 22 cm

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The groups within Finnish vocational upper secondary education and training (VET) are often heterogeneous with respect to the student's need for support in their studies. According to the national core curricula, Special Education Needs (SEN) students should in the first place, get their education in the same group as everyone else. This dissertation aims to clarify and create an understanding about how the ideals and intention of equality in education is constructed in communication among teachers in VET in the Swedish-speaking parts of Finland. Through this understanding it should be possible to highlight a potential which could ultimately contribute to a positive development of a more inclusive education within VET. The epistemological platform of the study is to be found within the post structuralist philosophy of language that is considered as subsumed in a social constructionist thinking. The data has been collected through focus group discussions in groups of 3–6 participants (teachers) in seven schools in Finnish-Swedish VET. The analyses are based on a discursive psychological analysis combined with an analysis based on Michel Foucault's concepts with an emphasis on the subject, government and power. Four discourser where identified in the analysis of teachers' constructions of the educational assignment in relation to SEN students. The most dominant was discussing the educational assignment as a pragmatic project i.e. as a matter of transmission of knowledge. The discourse included both interpretative repertoires where the heterogeneous group was constructed as self-evident and possible to manage as well as a constructed as an impossible project. The educational assignment was also constructed as a holistic project, as part of a democratic project, and as a labor market project. Each discourse contains both including as well as excluding features in relation to SEN students. The development of an inclusive practice can and should therefore include elements from all of them. Three discourses were identified in the analysis concerning teachers' versions of SEN students: students with difficulties and problems; students who do not use or do not have ability and students who are irresponsible and lack the will to study. Within the various discourses and interpretative repertoires were both constructs when teachers described a concern and kindness in relation to the individual SEN student and constructions where teachers mainly expressed fears that other students in the group would be negatively affected by students in need of special support. Results from the third research question conclude the results from the two others, the analysis is done out of a government perspective. In the material use of different government techniques are identified: disciplinary power through direct reprimands; pastoral power by a desire of insight in order to promote the opportunities for consultation and the use of bio-power that primarily focuses on what is best for the population and whose tool racism results in a legitimation of the exclusion of SEN students. The conclusion is that teachers in VET need to pay attention to inclusive and exclusive elements identified in various discourses.

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Att det förflutna spelar en avgörande roll vid såväl individers som kollektivs identitetsformering är snarast ett axiom inom historiefacket. Därför är det ingen överraskning att det förflutna brukas av grupper och deras ledare i syfte att befästa och vidmakthålla den egna identiteten. Forskningen kring detta – den så kallade historiebruksforskningen – har under de senaste decennierna upplevt ett starkt uppsving inom flera discipliner i Norden, framför allt inom historia och historiedidaktik. Historiebruksforskningen har ändå försummat att i någon högre grad ta i beaktande religiösa och teologiska aspekter, liksom också de teologiska ämnena har varit dåliga på att visa intresse för historiebruksfrågor. Avhandlingen kan därför ses som ett svar på denna ömsesidiga försummelse, och som ett bidrag till det aktuella och framväxande forskningsfältet kring historiebruk och kulturellt minne. Med utgångspunkt i den österbottniske mångsysslaren Anders Svedberg (1832–1889) undersöks mer konkret begreppet ”religiöst historiebruk”. Anders Svedberg växte upp, levde och verkade i det av väckelsen starkt präglade Munsala i svenska Österbotten. Han var en man av folket som kände till dess seder, bruk och historia. Därför kunde han ösa ur dess historia när han skrev sina tidningsartiklar och när han i lantdagen talade för allmogens demokratisering. Genom anspelningar på och hänvisningar till det förflutna refererade han ofta till kyrkohistoriska händelser i sin argumentation. Men vilka händelser använde han sig av? Varför hänvisade han till just de händelserna? Hur gjorde han det och i vilket syfte? Utifrån dessa konkreta frågor ger undersökningen förslag på vad som allmänt kan tänkas karakterisera ett religiöst historiebruk. Resultaten ger vid handen att ett religiöst historiebruk – särskilt när det bygger på en religiös minnesgemenskaps kulturella texter – har en förmåga att fungera legitimerande, mobiliserande och inkluderande/exkluderande. --------------------------------------------------------------------- Menneisyydellä on merkittävä osa sekä yksilön että yhteisön identiteetin muotoutumisessa. Tämä väittämä on yleisesti tunnustettu. Siksi ei ole yllättävää että eri yhteisöt ja niiden johtajat hyödyntävät menneisyyttä vahvistaakseen ja suojellakseen omaa identiteettiään. Niin kutsuttu historian käytön tutkimus on viime vuosikymmenillä vahvistanut asemaansa monilla tieteenaloilla pohjoismaissa, erityisesti historiatieteessä ja historian didaktiikassa. Historian käytön tutkimus ei kuitenkaan oleellisesti ole huomioinut uskonnollisia tai teologisia näkökulmia. Myöskään teologiset oppiaineet eivät ole osoittaneet suurempaa kiinnostusta historian käyttöä kohtaan. Väitöstutkimus vastaa siten näihin molempiin laiminlyönteihin ja se voidaan nähdä kirkkohistoriallisena panoksena historian käytön ja kulttuurisen muistin ajankohtaiseen ja kasvavaan tutkimusalaan. Tutkimus ottaa lähtökohdakseen pohjoismaalaisen monitaiturin Anders Svedbergin (1832–1889) ja tarkastelee hänen kautta käsitettä ”uskonnollinen historiankäyttö”. Anders Svedberg varttui, eli ja toimi Munsalassa aikaan jolloin herännäisyydellä ja muilla herätysliikkeillä oli vahva jalansija alueella. Svedberg tunsi pohjoismaalaisen maalaisväestön tavat ja tottumukset sekä alueen historian. Tämän takia hän osasi hyödyntää kyseistä historiaa kirjoittaessaan lehtiartikkeleita maalaisväestölle ja ajaessaan heidän etujaan säätyvaltiopäivillä. Kirjoituksissaan ja puheissaan hän viittasi usein historiallisiin ja kirkkohistoriallisiin tapahtumiin. Mutta mihin tapahtumiin hän viittasi? Miksi hän viittasi juuri näihin tapahtumiin, miten hän sen teki ja millä tavalla? Näiden konkreettisten kysymysten avulla tutkimus pyrkii tarkastelemaan miltä uskonnollinen historiankäyttö yleisellä tasolla voi näyttää. Tutkimustulos osoittaa että uskonnollisella historiankäytöllä – varsinkin perustuessaan uskonnollisen muistiyhteisön kulttuuriseen tekstiin – on kyky legitimoida, mobilisoida sekä sisällyttää ja sulkea pois ihmisiä.