Lärares syfte med laborativt arbete i NOundervisningen i årskurs 1-3 : En kvalitativ intervjustudie om sex lärares syfte med laborativt arbete i NO-undervisningen

Syftet med denna kvalitativa studie var att undersöka lärares syfte med laborativt arbete i årskurs 1-3 i NO-undervisningen samt vilka svårigheter som lärarna beskriver med det laborativa arbetssättet i NO-undervisningen. Studien har genomförts med hjälp av kvalitativa intervjuer av sex lärare som är verksamma i årskurserna 1-3. Alla tre årskurserna finns representerade i studien. De resultat som framkommit i studien är att lärare har flera olika syftet med det laborativa arbetet i NO-undervisningen. De syften som framkom var att öka förståelsen för naturvetenskapliga fenomen hos eleverna, öka elevernas motivation och intresse för naturvetenskap, erbjuda elever att uppleva naturvetenskap med händerna, erbjuda eleverna en möjlighet att träna på läroplanens mål, erbjuda eleverna en undervisning som utgår från varje elevs förutsättningar. Studiens frågeställningar berör även hur de intervjuade lärarna använder sig av laborativt arbete samt vilka svårigheter som lärarna uppger finnas med arbetssättet. Studien visar då att lärarna främst arbetar laborativt utomhus främst med biologi och att den svårigheten som flest lärare påpekade var avsaknaden av material.

Green mitigation strategy for cultural heritage: bacterial potential for biocide production

Several biosurfactants with antagonistic activity are produced by a variety of microorganisms. Lipopeptides (LPPs) produced by some Bacillus strains, including surfactin, fengycin and iturin are synthesized nonribosomally by mega-peptide synthetase (NRPS) units and they are particularly relevant as antifungal agents. Characterisation, identification and evaluation of the potentials of several bacterial isolates were undertaken in order to establish the production of active lipopeptides against biodeteriogenic fungi from heritage assets. Analysis of the iturin operon revealed four open reading frames (ORFs) with the structural organisation of the peptide synthetases. Therefore, this work adopted a molecular procedure to access antifungal potential of LPP production by Bacillus strains in order to exploit the bioactive compounds synthesis as a green natural approach to be applied in biodegraded cultural heritage context. The results reveal that the bacterial strains with higher antifungal potential exhibit the same morphological and biochemical characteristics, belonging to the genera Bacillus. On the other hand, the higher iturinic genetic expression, for Bacillus sp. 3 and Bacillus sp. 4, is in accordance with the culture antifungal spectra. Accordingly, the adopted methodology combining antifungal screening and molecular data is represent a valuable tool for quick identification of iturin-producing strains, constituting an effective approach for confirming the selection of lipopeptides producer strains.

Detection of human interchromosomal trans-splicing in sequence databanks.

Trans-splicing is a common phenomenon in nematodes and kinetoplastids, and it has also been reported in other organisms, including humans. Up to now, all in silico strategies to find evidence of trans-splicing in humans have required that the candidate sequences follow the consensus splicing site rules (spliceosome-mediated mechanism). However, this criterion is not supported by the best human experimental evidence, which, except in a single case, do not follow canonical splicing sites. Moreover, recent findings describe a novel alternative tRNA mediated trans-splicing mechanism, which prescinds the spliceosome machinery. In order to answer the question, ?Are there hybrid mRNAs in sequence databanks, whose characteristics resemble those of the best human experimental evidence??, we have developed a methodology that successfully identified 16 hybrid mRNAs which might be instances of interchromosomal trans-splicing. Each hybrid mRNA is formed by a trans-spliced region (TSR), which was successfully mapped either onto known genes or onto a human endogenous retrovirus (HERV-K) transcript which supports their transcription. The existence of these hybrid mRNAs indicates that trans-splicing may be more widespread than believed. Furthermore, non-canonical splice site patterns suggest that infrequent splicing sites may occur under special conditions, or that an alternative trans-splicing mechanism is involved. Finally, our candidates are supposedly from normal tissue, and a recent study has reported that trans-splicing may occur not only in malignant tissues, but in normal tissues as well. Our methodology can be applied to 5'-UTR, coding sequences and 3'-UTR in order to find new candidates for a posteriori experimental confirmation.