988 resultados para Turnera diffusa Willd. var. afrodisiaca (Ward) Urb (syn. T. aphrodisiaca)


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Syftet med studien är att undersöka sydfinlandssvenska högskolestuderandes kännedom om och ins¤llning till ett urval finlandssvenska ord och uttryck samt till dessa ords allmänsvenska motsvarigheter. För att undersöka detta har jag gjort en enkätundersökning bland svensksprÃ¥kiga högskolestuderande i Helsingfors. Jag undersöker i vilken utsträckning informanterna använder finlandssvenska ord och uttryck och i vilken utsträckning allmänsvenska. Jag undersöker även vilka finlandssvenska ord och uttryck de använder mest och vilka minst, samt vilka allmänsvenska ord och uttryck de använder mest och vilka minst. Dessutom undersöker jag om informanternas sprÃ¥kliga bakgrund har ett samband med deras kännedom om och användning av finlandssvenska respektive allmänsvenska ord och uttryck. Avsikten med den här undersökningen är att öka kunskapen om hur unga finlandssvenskar förhÃ¥ller sig till sin finlandssvenska varietet samt till den allmänsvenska varieteten som de i vuxen Ã¥lder förutsätts behärska Ã¥tminstone i nÃ¥gon mÃ¥n. Idén till enkätundersökningen kommer frÃ¥n Margareta SödergÃ¥rds och Sofie Tjärus studie Blivande barnträdgÃ¥rdslärares syn pÃ¥ finlandismer (2008). Urvalet finlandismer kommer frÃ¥n en mindre undersökning Goda och onda finlandismer som Mikael Reuter (2004) har gjort bland en grupp finlandssvenska och sverigesvenska sprÃ¥kvÃ¥rdare. Sammanlagt ingÃ¥r 55 finlandismer av olika slag i enkäten. För varje finlandism finns det även en eller fler allmänsvenska motsvarigheter och sammanlagt ingÃ¥r därför 122 ord och uttryck i enkäten. Mina informanter är 162 studerande vid tvÃ¥ svenska högskolor i Helsingfors. För att fÃ¥ reda pÃ¥ relevanta bakgrundsfakta om informanterna har jag använt samma formulär som Therese Leinonen i Svenskan i Finland ett sprÃ¥k i kläm? (Leinonen & Tandefelt 2000). Jag har utgÃ¥ende frÃ¥n informanternas generella sprÃ¥kanvändning delat in dem i tre grupper. En grupp vars vardag är finskdominerad, en vars vardag är svenskdominerad och en vars vardag utspelar sig till ungefär lika stor del pÃ¥ svenska som pÃ¥ finska. Undersökningen är kvantitativ och för att behandla materialet har statistikprogrammet SPSS använts. Studien visar att informanterna förhÃ¥ller sig rätt lika till finlandismerna och de allmänsvenska orden och uttrycken. De känner ungefär lika bra till de finlandssvenska och de allmänsvenska orden och uttrycken, men de prefererar ändÃ¥ i viss mÃ¥n finlandismerna framför de allmänsvenska orden och uttrycken. Mina informanter förefaller i viss mÃ¥n vara mer accepterande mot finskpÃ¥verkade finlandismer än vad Reuters (2004) informanter är, och de förhÃ¥ller sig mindre positiva till metaforiska uttryck än vad Reuters informanter gör. Informanter med en svensksprÃ¥kig vardag verkar använda allmänsvenska ord och uttryck i högre utsträckning än vad informanterna med en finsksprÃ¥kig vardag gör. Resultaten tyder dessutom pÃ¥ att informanterna med en svensksprÃ¥kig vardag ocksÃ¥ känner till fler allmänsvenska ord och uttryck även om de inte alltid själva är beredda att använda dem. Studien visar även att informanter med en svensksprÃ¥kig vardag använder en del metaforiska uttryck mer än vad informanterna med en finsksprÃ¥kig vardag gör. Det är överlag tydligt att undersökningens informanter, finlandssvenska högskolestuderande frÃ¥n södra Finland, varken har en speciellt stor kännedom om metaforiska uttryck eller en speciellt positiv ins¤llning till dessa. Bristande behärskning av metaforiska uttryck, idiom och kollokationer kan ses som ett första steg mot sprÃ¥kförlust och sett ur den synvinkeln är resultatet oroväckande. Det s¤rker den rÃ¥dande uppfattningen att allt inte s¥r helt rätt till med den svenska sprÃ¥kbehärskningen bland unga finlandssvenskar.

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An endocellulase (1→4)-β-d-glucan 4-glucanohydrolase was isolated from the culture filtrates of Chaetomium thermophile. The enzyme was homogeneous by PAGE and SDS-PAGE. The molecular weight was 36 000 by SDS-PAGE and 38 000 by gel filtration. It was a glycoprotein. From the amino acid composition, it was found to be rich in glycine, threonine, and aspartic and glutamic acids, but contained only low proportions of histidine and sulfur-containing amino acids. It was optimally active at pH 6 and at 60°. The enzyme did not hydrolyze cellobiose and cellotriose, but hydrolyzed cello-tetraose, -pentaose, and -hexaose at comparable rates. It was specific for molecules containing β-(1→4) linkages. It showed high activity towards amorphous cellulose, and the reaction products contained cellobiose to cellopentaose, showing that it effects random cleavage of cellulose.

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This paper is concerned with the influence of different levels of complexity in modelling various constituent subsystems on the dynamic stability of power systems compensated by static var systems (SVS) operating on pure voltage control. The system components investigated include thyristor controlled reactor (TCR) transients, SVS delays, network transients, the synchronous generator and automatic voltage regulator (AVR). An overall model is proposed which adequately describes the system performance for small signal perturbations. The SVS performance is validated through detailed nonlinear simulation on a physical simulator.

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The details of the first total synthesis of a natural thapsane lg containing three contiguous quaternary carbon atoms, starting from cyclogeraniol (9) '5 described. The Claisen rearrangement of 9 with methoxypropene in the presence of a catalytic amount of propionic acid produced ketone 10. Rhodium acetate-catalyzed intramolecular cyclopropanation of a-diazo-&keto ester 12, obtained from 10 via 8-keto ester 8, furnished cyclopropyl keto ester 7. Lithium in liquid ammonia reductive cleavage of cyclopropyl compound 7 gave a 1:l mixture of hydrindanone 6 and keto1 13. Wittig methylenation of 6 furnished ester 21. Epoxidation of 21, followed by BF3-OEt2-catalyzed rearrangement of epoxide 23 afforded hemiacetal 25. Treatment of hemiacetal 25 with triethylsilane in trifluoroacetic acid furnished lactone 22, a degradation product of various thapsanes. Finally, DIBAH reduction of lactone 22 generated the thapsane

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The ability of Static Var Compensators (SVCs) to rapidly and continuously control reactive power in response to changing system conditions can result in the improvement of system stability and also increase the power transfer in the transmission system. This paper concerns the application of strategically located SVCs to enhance the transient stability limits and the direct evaluation of the effect of these SVCs on transient stability using a Structure Preserving Energy Function (SPEF). The SVC control system can be modelled from the steady- state control characteristic to accurately simulate its effect on transient stability. Treating the SVC as a voltage-dependent reactive power load leads to the derivation of a path-independent SPEF for the SVC. Case studies on a 10-machine test system using multiple SVCs illustrate the effects of SVCs on transient stability and its accurate prediction.

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Phenylboronic acids can exist, in principle, in three different conformers (syn,syn; syn,anti and anti,anti) with distinct energy profiles. In their native state, these compounds prefer the energetically favored syn, anti-conformation. In molecular complexes, however, the functionality exhibits conformational diversity. In this paper we report a series of co-crystals, with N-donor compounds, prepared by a design strategy involving the synthons based on the syn, syn-conformation of the boronic acid functionality. For this purpose, we employed compounds with the 1,2-diazo fragment (alprazolam, 1H-tetrazole, acetazolamide and benzotriazole), 1,10-phenanthroline and 2,2'-bipyridine for the co-crystallization experiments. However, our study shows that the mere presence of the 1,2-diazo fragment in the coformer does not guarantee the successful formation of co-crystals with a syn, syn-conformation of the boronic acid. [GRAPHICS] The -B(OH)(2) fragment makes unsymmetrical O-H center dot center dot center dot N heterosynthons with alprazolam (ALP) and 1,10-phenanthroline (PHEN). In the co-crystals of phenylboronic acids with 1H-tetrazole (TETR) and 2,2'-bipyridine (BPY), the symmetrical boronic acid dimer is the major synthon. In the BPY complex, boronic acid forms linear chains and the pyridine compound interacts with the lateral OH of boronic acid dimers that acts as a connector, thus forming a ladder structure. In the TETR complex, each heterocycle interacts with three boronic acids. While two boronic acids interact using the phenolic group, the third molecule generates O-H center dot center dot center dot N hydrogen bonds using the extra OH group, of -B(OH)(2) fragment, left after the dimer formation. Thus, although molecules were selected retrosynthetically with the 1,2-diazo fragment or with nearby hetero-atoms to induce co-crystal formation using the syn,syn-orientation of the -B(OH)(2) functionality, co-crystal formation is in fact selective and is probably driven by energy factors. Acetazolamide (ACET) contains self-complementary functional groups and hence creates stable homosynthons. Phenylboronic acids being weak competitors fail to perturb the homosynthons and hence the components crystallize separately. Therefore, besides the availability of possible hydrogen bond acceptors in the required position and orientation, the ability of the phenyl-boronic acid to perturb the existing interactions is also a prerequisite to form co-crystals. This is illustrated in the table below. In the case of ALP, PHEN and BPY, the native structures are stabilized by weak interactions and may be influenced by the boronic acid fragment. Thus phenylboronic acids can attain co-crystals with those compounds, wherein the cyclic O-H center dot center dot center dot N hydrogen bonds are stronger than the individual homo-interactions. This can lower the lattice energy of the molecular complex as compared with the individual crystals. [GRAPHICS] Phenylboronic acids show some selectivity in the formation of co-crystals with N-heterocycles. The differences in solubility of the components fall short to provide a possible reason for the selective formation of co-crystals only with certain compounds. These compounds, being weak acids, do not follow the Delta pK(a) analysis and hence fail to provide any conclusive observation. Theoretical results show that of the three conformers possible, the syn,anti conformer is the most stable. The relative stabilities of the three conformers syn,anti,syn,syn and anti,anti are 0.0, 2.18 and 3.14 kcal/mol, respectively. The theoretical calculations corroborate the fact that only energetically favorable synthons can induce the formation of heterosynthons, as in ALP and PHEN complexes. From a theoretical and structural analysis it is seen that phenylboronic acids will form interactions with those molecules wherein the heterocyclic and acidic fragments can interrupt the homosynthons. However, the energy profile is shallow and can be perturbed easily by the presence of competing functional groups (such as OH and COOH) in the vicinity. [GRAPHICS] .

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This paper presents a methodology for selection of static VAR compensator location based on static voltage stability analysis of power systems. The analysis presented here uses the L-index of load buses, which includes voltage stability information of a normal load flow and is in the range of 0 (no load of system) to 1 (voltage collapse). An approach has been presented to select a suitable size and location of static VAR compensator in an EHV network for system voltage stability improvement. The proposed approach has been tested under simulated conditions on a few power systems and the results for a sample radial network and a 24-node equivalent EHV power network of a practical system are presented for illustration purposes. © 2000 Published by Elsevier Science S.A. All rights reserved.

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Boerhaavia diffusa is a traditional herbal medicine extensively used in the Ayurveda and Unani forms of medicine in India and many parts of the world. Different parts of the plant are used as an appetizer, alexiteric, eye tonic, for flushing out the renal system, and to treat blood pressure. This study was conducted to evaluate the in vivo genotoxic and/or antigenotoxic potential of punarnavine, a separated alkaloid from the root of B. diffusa using toxicity studies (OECD guideline 474, 1997). The genotoxic and antigenotoxic potential of punarnavine was assayed using the comet assay on lymphocytes, liver, spleen, brain, and bone marrow as well as using the micronucleus test in bone marrow cells including the in vitro chromosomal aberration test. The results demonstrated that none of the tested doses of punarnavine showed genotoxic effects by the comet assay, or clastogenic effects in the micronucleus test. On the other hand, for all cells evaluated, the three tested doses of punarnavine promoted inhibition of DNA damage induced by cyclophosphamide. Based on these results, we concluded that punarnavine, an alkaloid from the Boerhaavia diffusa root, has no genotoxic or clastogenic effects in our experimental conditions. However, it caused a significant decrease in DNA damage induced by cyclophosphamide. It is suggested that the antigenotoxic properties of this alkaloid may be of great pharmacological importance and beneficial for cancer prevention.

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Cryptococcus neoformans is a pathogenic basidiomycetous yeast responsible for more than 600,000 deaths each year. It occurs as two serotypes (A and D) representing two varieties (i.e. grubii and neoformans, respectively). Here, we sequenced the genome and performed an RNA-Seq-based analysis of the C. neoformans var. grubii transcriptome structure. We determined the chromosomal locations, analyzed the sequence/structural features of the centromeres, and identified origins of replication. The genome was annotated based on automated and manual curation. More than 40,000 introns populating more than 99% of the expressed genes were identified. Although most of these introns are located in the coding DNA sequences (CDS), over 2,000 introns in the untranslated regions (UTRs) were also identified. Poly(A)-containing reads were employed to locate the polyadenylation sites of more than 80% of the genes. Examination of the sequences around these sites revealed a new poly(A)-site-associated motif (AUGHAH). In addition, 1,197 miscRNAs were identified. These miscRNAs can be spliced and/or polyadenylated, but do not appear to have obvious coding capacities. Finally, this genome sequence enabled a comparative analysis of strain H99 variants obtained after laboratory passage. The spectrum of mutations identified provides insights into the genetics underlying the micro-evolution of a laboratory strain, and identifies mutations involved in stress responses, mating efficiency, and virulence.