973 resultados para 1,3,5-Triazine


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Syftet med studien är att undersöka hur lärare i årskurs 1-3 uppfattar begreppet hållbar utveckling samt undervisning om hållbar utveckling i So-ämnena och dess relevans för elever i årskurs 1-3. Vidare syftar studien till att undersöka hur lärare beskriver att de planerar och genomför undervisning om hållbar utveckling i So-ämnena i årskurs 1-3. Studiens syfte besvaras med hjälp av en kvalitativ metod i form av intervjuer med lärare. Resultatet visar att lärare ser på hållbar utveckling och undervisning kring detta utifrån tre perspektiv som i studien benämns som miljö, socialt perspektiv samt ett omfattande begrepp. Det mest framträdande perspektivet är miljö följt av ett socialt perspektiv. Genom undervisning kopplat till hållbar utveckling i So får eleverna lära sig om hur man tar hand om naturen men även om sociala och samhälleliga frågor. Undervisningen bidrar även till att eleverna får kunskaper om demokrati samt till att ge eleverna förståelse för andra människors situation. I studien framkommer att lärare ser undervisning om hållbar utveckling som relevant för elever i årskurs 1-3 gällande miljö och sociala frågor.

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Syftet med studien var att ta reda på hur lärare ser på närområdet och hur de bedriver undervisning i närområdet utanför klassrummet inom de samhällsorienterande ämnena i årskurs 1-3. Vidare var syftet att undersöka vad lärare hade för åsikter om undervisningens inverkan på elevers lärande i årskurs 1-3 samt vad de såg för möjligheter och problem med undervisningsformen. För att besvara studiens syfte intervjuades sex lärare genom semistrukturerade intervjuer. Intervjuerna analyserades med en innehållsanalys där mönster söktes i informanternas svar. Resultatet visade att samtliga lärare anser att undervisning i närområdet utanför klassrummet har en positiv inverkan på elevers lärande men att alla lärare inte bedriver undervisning i denna form. Problem som hindrar lärare från att bedriva undervisning i närområdet är tids- och ekonomibrist samt bristen på forskning inom ämnet och vissa lärare saknar även viljan till att bedriva undervisning på detta sätt. I resultatet presenteras även några olika exempel på hur lärare undervisar i närområdet utanför klassrummet och vad de ser för möjligheter med denna undervisningsform.

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Studien har haft som syfte att undersöka hur lärare i årskurs 1-3 planerar och genomförundervisning i teknik. Frågeställningarna som tagits fram för att för att få svar på studiens syfteär: hur beskriver lärarna att de planerar för teknikämnet, allmänt och i relation till det centralainnehållet för årskurs 1-3?, hur beskriver lärarna att de undervisar relaterat till det centralainnehållet i teknik för årskurs 1-3? samt vilka undervisningsmetoder används, enligt lärarna?Dessa frågor har det sökts svar på genom kvalitativa intervjuer med åtta lärare i årskurs 1-3.I resultatet framkommer att teknik är ett ämne som inte fullt ut har fått fäste i årskurs 1-3, då detvisar sig att flera lärare i studien saknar förtrogenheten med ämnets kursplan och planering ochundervisning beskrivs till stor del bedrivas tillsammans med No-ämnena. Teknikämnet har haften egen kursplan i tjugo år. Trots detta saknas på många skolor lärare med utbildning i tekniksamt material. Det framgår dock också i resultatet att några av de intervjuade lärarna ärintresserade och väl insatt i ämnets kursplan, även material i form av Skellefte-tekniken och NTAanvänds av flertalet av lärarna i studien. Teknikämnet behöver stärkas ytterligare som eget ämneoch i högre utsträckning undervisas separat för att ge eleverna en god uppfattning av vad som är teknik

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I den här studien har syftet varit att undersöka hur matematikläxor påverkar elevernas kunskapsutveckling. Det finns många olika perspektiv att belysa detta på, i det här fallet har fokus legat på lärarens undervisning i årskurs 1-3, där matematikläxor utgör en del av undervisningen som ska ge eleverna förutsättningar och möjligheter att nå kunskapsmålen. Studien har utgått från följande frågeställning: Vad kan vanligt förekommande matematikläxor ge elever och deras kunskapsutveckling? I arbetet med att undersöka denna frågeställning har en systematisk litteraturstudie genomförts och vetenskapliga artiklar har sökts fram via databaserna ERIC (Ebsco) och LIBRIS. Vetenskapliga artiklar har utifrån beskrivna kriterier valts ut, granskats och bidragit med kunskaper. Resultatet visar att förekomsten av matematikläxor bygger på traditioner och uppfattningar, att en hög läxfrekvens inte automatiskt utvecklar kunskaper hos eleverna, att elevernas förkunskaper och intellektuella förmågor har betydelse och att det är något som lärare måste ta hänsyn till, att olika typer av förståelse kan utvecklas via läxorna och att matematikläxor som genomförs under lektionstid med stöttning av lärare ökar chansen för fler elever att tillgodogöra sig kunskaperna.

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A newsletter published periodically to keep the faculty, students, staff, and community informed about the activities taking place on the campus of LaGuardia Community College. Cover article: SONY SHIFT SCHEDULED SOON, SPOKESMAN SAYS. Other entries include: CUNY TEACHING EXCELLENCE AWARD TO PROFESSOR MILLER; CHILD CARE LEAVE ADOPTED BY BHE; NINETY SENIOR CITIZENS RECEIVE CERTIFICATES; COLLEGE COMMENCEMENT TO BE HELD AT QUEENS COLLEGE AUDITORIUM; DEAN PALMER TO SING AT SEPT. 16, COMMENCEMENT; FOUR MORE PARAPROFESSIONALS COMPLETE DEGREES.”

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A formação interna da estrutura de uma peça fundida deve determinar as características mecânicas dessa peça, quando em serviço. Dessa forma, torna-se fundamental conhecer e parametrizar os elementos que influem na formação da estrutura do componente sólido, para o desenvolvimento adequado de sistemas de solidificação que permitam conduzir a melhoria da qualidade de uma peça no processo de solidificação. Modelos numéricos podem ser empregados para a determinação da formação estrutural, entretanto estes devem ser aferidos adequadamente para garantir sua aplicabilidade. No trabalho em questão, desenvolveu-se uma metodologia que permitiu a aferição de um modelo numérico para a previsão das condições de resfriamento de ligas de alumínio. Elaborou-se um conjunto de coquilhas e moldes que permitiram o acoplamento e verificação da estrutura formada na solidificação em diferentes situações de resfriamento, observando principalmente a direção de extração de calor e a taxa de resfriamento associada. O modelo numérico aplicado respondeu coerentemente aos resultados obtidos permitindo a previsão da estrutura solidificada pela observação dos resultados de evolução das isotermas solidus e liquidus no interior dos sistemas.

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Water-insoluble glucan was isolated from the baker’s yeast Saccharomyces cerevisiae. The yeast cells were treated with alkali and the residue then with acid. Chemical and NMR (1D and 2D) analyses showed that a linear (1→3)-β-glucan was purified that was not contaminated with other carbohydrates, proteins or phenolic compounds. The effects of the glucan on wound healing were assessed in human venous ulcers by histopathological analysis after 30 days of topical treatment. (1→3)-β-glucan enhanced ulcer healing and increased epithelial hyperplasia, as well as increased inflammatory cells, angiogenesis and fibroblast proliferation. In one patient who had an ulcer that would not heal for over 15 years, glucan treatment caused a 67.8% decrease in the area of the ulcer. This is the first study to investigate the effects of (1→3)-β-glucan on venous ulcer healing in humans; our findings suggest that this glucan is a potential natural biological response modifier in wound healing

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To investigate the role of β-(1-3)-D-glucan on 99mTc labelled Escherichia coli translocation and cytokines secretion in rats submitted to small bowel ischemia/reperfusion injury. Methods: Five groups (n=10 each) of Wistar rats were subjected to control(C), sham(S), group IR subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R), and group I/R+glucan subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R) and injected with 2mg/Kg intramuscular. Translocation of labelled bacteria to mesenteric lymph nodes, liver, spleen, lung and serum was determined using radioactivity/count and colony forming units/g(CFU/g). Serum TNFα, IL-1β, IL-6, IL-10 were measured by ELISA. Results: CFU/g and radioactivity/count were higher in I/R than in I/R+glucan rats. In C, S and S+glucan groups, bacteria and radioactivity/count were rarely detected. The I/R+glucan rats had enhancement of IL-10 and suppressed production of serum TNFα, IL-1β and, IL-6, compared to I/R untreated animals. Conclusion: The β-(1-3)-D-glucan modulated the production of pro-inflammatory and anti-inflammatory cytokines during bowel ischemia/reperfusion, and attenuated translocation of labelled bacteria

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Water-insoluble glucan was isolated from the baker’s yeast Saccharomyces cerevisiae. The yeast cells were treated with alkali and the residue then with acid. Chemical and NMR (1D and 2D) analyses showed that a linear (1→3)-β-glucan was purified that was not contaminated with other carbohydrates, proteins or phenolic compounds. The effects of the glucan on wound healing were assessed in human venous ulcers by histopathological analysis after 30 days of topical treatment. (1→3)-β-glucan enhanced ulcer healing and increased epithelial hyperplasia, as well as increased inflammatory cells, angiogenesis and fibroblast proliferation. In one patient who had an ulcer that would not heal for over 15 years, glucan treatment caused a 67.8% decrease in the area of the ulcer. This is the first study to investigate the effects of (1→3)-β-glucan on venous ulcer healing in humans; our findings suggest that this glucan is a potential natural biological response modifier in wound healing

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To investigate the role of β-(1-3)-D-glucan on 99mTc labelled Escherichia coli translocation and cytokines secretion in rats submitted to small bowel ischemia/reperfusion injury. Methods: Five groups (n=10 each) of Wistar rats were subjected to control(C), sham(S), group IR subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R), and group I/R+glucan subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R) and injected with 2mg/Kg intramuscular. Translocation of labelled bacteria to mesenteric lymph nodes, liver, spleen, lung and serum was determined using radioactivity/count and colony forming units/g(CFU/g). Serum TNFα, IL-1β, IL-6, IL-10 were measured by ELISA. Results: CFU/g and radioactivity/count were higher in I/R than in I/R+glucan rats. In C, S and S+glucan groups, bacteria and radioactivity/count were rarely detected. The I/R+glucan rats had enhancement of IL-10 and suppressed production of serum TNFα, IL-1β and, IL-6, compared to I/R untreated animals. Conclusion: The β-(1-3)-D-glucan modulated the production of pro-inflammatory and anti-inflammatory cytokines during bowel ischemia/reperfusion, and attenuated translocation of labelled bacteria

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The frequency of disseminated candidiasis caused by yeast has enhancing in intensive care unit. Despite the availability of new antifungal drugs, C. albicans sepsis mortality causes can be as high as 30-40%. So, it has been needed to looking for a new therapeutic medicament that helps in treatment and prevention of this infection. Previous data that demonstrated that particulated β-glucan stimulates the immune system and experiments of this work were conducted to investigating if β-glucan extracted from Saccharomices cerevisiae, could modified the evolution of mouse model C. albicans systemic infection. Balb/c mice with sepsis and β-1,3 glucan treated or not were analyzed the influence of β-1,3 glucan in survival of the animals, in the fungal burdens in kidney, in the production of urea and TNF even in the histopathology of kidney. The experiments shown that the infected animals a nd glucan treated had great survival (p<0,05), less unit form colony in kidney and normal levels of urea. In the kidney histopathology of not glucan treated animals it has seen more lesions when compared with treated animals. So we conclude that β-1,3 glucan could stimulate the immune system against disseminated C. albicans

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Two botryosphaerans, exopolysaccharides (EPS) secreted by the ascomyceteous fungus Botryosphaeria rhodina, when grown on sucrose and fructose as sole carbon sources, were structurally compared after their isolation from the culture medium. Both EPS were submitted to trypsin digestion, and eluted as a single peak on gel filtration. Total acid hydrolysis yielded only glucose, and data from methylation analysis and Smith degradation indicated that both EPS constituted a main chain of glucopyranosyl beta(1 -> 3) linkages substituted at O-6. The products obtained after partial acid hydrolysis demonstrated side chains consisting of glucosyl- and gentiobiosyl- linked beta(1 -> 6) residues. C-13-NMR spectroscopy studies showed that all glucosidic linkages were of the beta-configuration. The carbon source affected the side chain structures of botryosphaeran but not the main chain makeup. Sucrose produced less branching (21%) than fructose (31%). (c) 2005 Published by Elsevier Ltd.

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The exopolysaccharide, Botryosphaeran, produced by the ligninolytic, ascomycetcous fungus Botryosphaeria sp., was isolated from the extracellular fluid by precipitation with ethanol, and purified by gel permeation chromatography to yield a carbohydrate-rich fraction (96%) composed mainly of glucose (98%). Infra-red and C-13 NMR spectroscopy showed that all the glucosidic linkages were in the beta-configuration. Data from methylation analysis and Smith degradation indicated that Botryosphaeran was a (1 --> 3)-beta-(D)-glucan with approx 22% side branching at C-6. The products obtained from partial acid hydrolysis demonstrated that the side branches consisted of single (1 --> 6)-beta-linked glucosyl, and (1 --> 6)-beta-linked gentiobiosyl residues.[GRAPHICS](C) 2003 Elsevier Ltd. All rights reserved.

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Botryosphaeran, a (1 -> 3; 1 -> 6)-beta-D-glucan produced by Botryosphaeria rhodina, and laminarin were hydrolysed by two fungal beta-glucanases predominantly of the 1,3-type produced by B. rhodina and Trichoderma harzianum Rifai grown on botryosphaeran as sole carbon source. Both beta-glucanase preparations presented different modes of attack on botryosphaeran and laminarin. Laminarin was hydrolysed to the extent of similar to 50% in 1 hand 100% within 24 h, and its hydrolysis products were mainly glucose and gentiobiose, and lesser amounts of laminaribiose and oligosaccharides of DP 3-4 during the early stages of hydrolysis, while botryosphaeran 'yielded mainly glucose and gentiobiose with some trisaccharide, but no laminaribiose or tetrasaccharide when hydrolysed by the T. harzianum enzyme. By contrast, B. rhodina beta-1,3-glucanases produced predominantly glucose during all stages of botryosphaeran hydrolysis. Some physicochemical properties of the 1,3- and 1,6-beta-glucanases, and beta-glucosidases contained in the two fungal P-glucanase preparations are also described for the first time. (c) 2006 Elsevier Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)