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  • 751.
    Siira, Sofia
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Coralic, Sanela
    Södertörns högskola, Institutionen för livsvetenskaper.
    Eldelöv, Madeleine
    Södertörns högskola, Institutionen för livsvetenskaper.
    Från snopp till kropp: En c-uppsats utformad inom sex och samlevnad2008Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

     

    Detta är endast en del av ett stort arbete, på grund av omständigheterna (till exempel möjligheten att publicera en power point) har vi varit tvungna att begränsa vår publikation till lärarhandledningen. Det finns också en elevutgåva, power point-presentation samt ett prov som inte publiceras. För att ta del av dessa krävs möjlighet att komma åt Biologi C för lärares kurswebb Vt-2008 på Södertörns högskolas intranät.

     

  • 752.
    Silverstein, Rebecca A
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Ekwall, Karl
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Sin3: a flexible regulator of global gene expression and genome stability2005Ingår i: Current Genetics, ISSN 0172-8083, E-ISSN 1432-0983, Vol. 47, nr 1, s. 1-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    SIN3 was first identified genetically as a global regulator of transcription. Sin3 is a large protein composed mainly of protein-interaction domains, whose function is to provide structural support for a heterogeneous Sin3/histone deacetylase (HDAC) complex. The core Sin3/HDAC complex is conserved from yeast to man and consists of eight proteins. In addition to HDACs, Sin3 can sequester other enzymatic functions, including nucleosome remodeling, DNA methylation, N-acetylglucoseamine transferase activity, and histone methylation. Since the Sin3/HDAC complex lacks any DNA-binding activity, it must be targeted to gene promoters by interacting with DNA-binding proteins. Although most research on Sin3 has focused on its role as a corepressor, mounting evidence suggests that Sin3 can also positively regulate transcription. Furthermore, Sin3 is key to the propagation of epigenetically silenced domains and is required for centromere function. Thus, Sin3 provides a platform to deliver multiple combinations modifications to the chromatin, using both sequence-specific and sequence-independent mechanisms.

  • 753.
    Silverstein, Rebecka A.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Histone deacetylases and their co-regulators in schizosaccharomyces pombe2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The DNA in every eukaryotic cell is wrapped around eight core histones to form the nucleosome. Therefore all events that involve DNA must also involve chromatin and nucleosomes. By regulating chromatin structure the cell can regulate the reactivity of the DNA. One of the most common ways of altering nucleosomes is the acetylation of lysine residues. Two enzymes are required to maintain the correct equilibrium for optimal cell growth: histone acetyltransferases (HATs) and histone deacetyltransferases (HDACs). In general, histone hypoacetylation is correlated with transcriptional inactivation, while hyperacetylation is correlated with active gene transcription. In Schizosaccharomyces pombe, mating type loci are silenced. Deletion of HDAC Hos2 had previously been shown to slightly increase silencing at the mating type locus. To assess whether any other HDAC was necessary for mating type silencing, cells were treated with HDAC poison Trichostatin A (TSA). TSA was found to cause a mild derepression of the mating type locus, indicating that another HDAC was responsible for silencing in this region. The RNA interference nuclease Dcr1 was later identified, and showed to degrade double stranded RNA into small nucleotide fragments. Deletion of dcr1 caused chromosome segregation defects and derepression of centromeric silencing. Rpd3 in S. cerevisiae is recruited to genomic targets by interacting with co-regulator Sin3. S. pombe has three Sin3 homologs. Pst1 interacts with the HDAC Clr6, and like Clr6 is an essential gene, mutants of which display chromosome mis-segregation and derepression of centromeric silencing. Pst1 was required for centromeric cohesion, and localized to centromeres in late S phase. Thus a co-repressor paradigm could be applied to centromere silencing as well. A comparative characterization of HDACs in S. pombe showed that the HDACs had different localizations and histone specificities. The comparison of HDACs was taken further with a genome wide expression analysis and histone density study of mutants. Results indicated that Clr6 was most often involved in promoter initiated gene repression, whereas Hos2 promoted the high expression of growth related genes by deacetylating H4K16ac in their coding regions. A class II HDAC, Clr3, was found to act cooperatively with Sir2 throughout the genome. Using a genomic approach to analyze Pst3, it was established that Clr6 and Pst3 could cooperate to negatively regulate genes by binding to their promoter regions. On the other hand, Pst3 was also involved in the up-regulation of ribosome biosynthesis genes, and could bind to the rDNA.

  • 754.
    Simoff, Ivailo
    Södertörns högskola, Institutionen för livsvetenskaper.
    Ribosomal proteins L5 and L15: Functional characterisation of important features, in vivo2009Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Protein synthesis is a highly regulated and energy consuming process, during which a large ribonucleoprotein particle called the ribosome, synthesizes new proteins. The eukaryotic ribosome consists of two unequal subunits called: small and large subunits. Both subunits are composed of ribosomal RNA (rRNA) and ribosomal proteins (r-proteins).

    Although rRNAs build the matrix of the ribosome and carries out catalysing of the peptide-bond formation between amino acids, r-proteins also appear to play important structural and functional roles. The primary role of r-proteins is to initiate the correct tertiary fold of rRNA and to organize the overall structure of the ribosome.

    In this thesis, I focus on two proteins from the large subunit of the eukaryotic ribosome: r-proteins L5 and L15 from bakers yeast S. cerevisiae. Both r-proteins are essential for ribosome function. Their life cycle is primarily associated with rRNA interactions. As a consequence, the proteins show high sequence homology across the species borders. Furthermore, both L5 and L15 are connected to human diseases, which makes the study their role in ribosome biogenesis and ribosome function important.

    By applying random- and site-directed mutagenesis, coupled with functional complementation tests, I aimed to elucidate functionally regions in both proteins, implicated in transport to the cell nucleus, protein-protein interactions and/or rRNA binding. The importance of individual and multiple amino acid exchanges in the primary sequence of rpL5 and rpL15 were studied in vivo. The obtained results show that S. cerevisiae rpL15 was tolerant to amino acid exchanges in the primary sequence, whereas rpL5 was not. Consequently, A. thaliana rpL15 could substitute for the function of wild type rpL15, whereas none of the tested orthologous proteins to rpL5 could substitute yeast rpL5 in vivo. These observations further emphasize the importance of studying r-proteins as separate entities in the ribosome context.

  • 755.
    Simoff, Ivailo
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Moradi, Hossein
    Södertörns högskola, Institutionen för livsvetenskaper.
    Nygård, Odd
    Södertörns högskola, Institutionen för livsvetenskaper, Biologi. Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Functional characterization of ribosomal protein L15 from Saccharomyces cerevisiae2009Ingår i: Current Genetics, ISSN 0172-8083, E-ISSN 1432-0983, Vol. 55, nr 2, s. 111-125Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study we provide general information on the little studied eukaryotic ribosomal protein rpL15. Saccharomyces cerevisiae has two genes, YRPL15A and YRPL15B that could potentially code for yeast rpL15 (YrpL15). YRPL15A is essential while YRPL15B is dispensable. However, a plasmid-borne copy of the YRPL15B gene, controlled by the GAL1 promoter or by the promoter controlling expression of the YRPL15A gene, can functionally complement YrpL15A in yeast cells, while the same gene controlled by the authentic promoter is inactive. Analysis of the levels of YrpL15B-mRNA in yeast cells shows that the YRPL15B gene is inactive in transcription. The function of YrpL15A is highly resilient to single and multiple amino acid substitutions. In addition, minor deletions from both the N- and C-terminal ends of YrpL15A has no effect on protein function, while addition of a C-terminal tag that could be used for detection of plasmid-encoded YrpL15A is detrimental to protein function. YrpL15A could also be replaced by the homologous protein from Arabidopsis thaliana despite almost 30% differences in the amino acid sequence, while the more closely related protein from Schizosaccharomyces pombe was inactive. The lack of function was not caused by a failure of the protein to enter the yeast nucleus.

  • 756.
    Simoff, Ivailo
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Stockholms universitet.
    Moradi, Hossein
    Södertörns högskola, Institutionen för livsvetenskaper. Stockholms universitet.
    Nygård, Odd
    Södertörns högskola, Institutionen för livsvetenskaper.
    Implications of N-terminal sequence elements in S. cerevisiae ribosomal protein L5Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Yeast ribosomal protein L5 (YrpL5) is an essential 5S rRNA-binding protein that forms the central protuberance of the large ribosomal subunit. Formation of the binary rpL5.5S rRNA complex is a prerequisite for nuclear import of rpL5 and for ribosome assembly. The involvment of the N-terminal sequences of YrpL5 in 5S rRNA interaction and nuclear import was studied by mutagenesis and functional complementation in S. cerevisiae. Furthermore, the ability of YrpL5 orthologous proteins from M. musculus (MrpL5), D. melanogaster (DrpL5) and A. thaliana (ArpL5) were non-functional in yeast cells. Nuclear import of YrpL5 requires conserved sequence elements in the N-terminus. Despite the presence of these elements in ArpL5, this protein was not recognized by the nuclear import machinery in yeast. This failure was probably due to lack of stable complex formation with yeast 5S rRNA.

  • 757.
    Simoff, Ivailo
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Nygård, Odd
    Södertörns högskola, Institutionen för livsvetenskaper.
    Locating the nuclear localization signal in S. cerevisiae ribosomal protein L15AManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Newly synthesized ribosomal proteins (r-proteins) are efficiently transported from the cytoplasm to the site of ribosome assembly in the nucleolus. Nuclear import is facilitated by the presence of a nuclear localization signal (NLS) whereas the nucleolar accumulation requires a nucleolar localization signal (NoLS). In this study we located the NLS of the essential r-protein YrpL15A by studying the ability of various YrpL15A-gfp constructs to enter the nucleus and nucleolus. We found that the NLS signal is located in the C-terminal part of the protein. The identified sequence was sufficient to direct the reporter construct to the nucleus in yeast cells. This protein fragment contains a sequence that resembles a classical monopartite NLS. The fragment also contains a NoLS as seen by the partial co-localization of reporter construct with the nucleolar marker protein nop1. Orthologs of YrpL15A such as rpL15B from Arabidopsis thaliana and rpL15A from Schizosaccharomyces pombe were also able to enter the nucleus and nucleolus of yeast cells, suggesting that their NLS and NoLS are similar to that found in YrpL15. These results are discussed in relation to sequence similarities/dissimilarities. YrpL15A containing a C-terminal tag was unable to assemble into large ribosomal subunits that were transported to the cytoplasm.

  • 758.
    Sinha, Indranil
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Intstitutet.
    Genome-wide patterns of histone modifications in fission yeast2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    DNA is wrapped almost two times around a group of proteins called histones to form a chromosomal structure known as the nucleosome. Both DNA and histones can be modified with different chemical tags by several enzymes to activate or suppress a particular gene or group of genes. Histones can be covalently modified at several places. Among many different types of post-translational histone modifications, histone acetylation and methylation are two important modification types that are associated with transcriptional activation and repression. Histone acetylation and methylation can be added by histone acetyltransferases (HATs) and histone methyletransferases (HMTs), whereas these modifications can be removed by histone deacetylases (HDACs) and histone demethylases (HDMs). Histone modifications are not only involved in the regulation of gene expression, but also in DNA-based processes, such as replication, repair, and the formation and maintenance of heterochromatin. Combinations of modified and unmodified states of histones can form distinct histone modification patterns. In many different genome-wide studies, it was observed that a distinctive pattern of histone modification in various organisms is important for gene regulation, DNA replication, chromosome segregation and heterochromatin-mediated silencing. In this thesis, we have conducted several genome-wide investigations to uncover different histone modification patterns and their roles in transcriptional control in fission yeast. Our analysis of six different HDACs in fission yeast showed that Clr6 and Clr3 are mainly involved in keeping repressed genes silent; Sir2 and Hst2 repress non-expressed genes, and Hst4 acts globally to reduce gene expression, whereas Hos2 is required for the activation of gene expression. By investigating the influence of each HDAC on nucleosome density, we found that all sirtuins and Hos2 enzymes are required to maintain normal nucleosome density and distribution in the S. pombe genome. We have reported that histone acetylation patterns show a 5` to 3` polarity, i.e., the modification levels peak near the ATG and gradually decrease in the coding regions. We also found that histone acetylation patterns depend on gene expression but are independent of gene length. Comparing our data with other published datasets, we observed that different HDAC mutants affect acetylation in different parts of open reading frames (ORFs). We have demonstrated that histone H4 acetylation proceeds in the direction from K16 to K5, consistent with a `zip` model that may be involved in transcriptional control. Our analysis revealed antagonistic crosstalk between H3K36me2/me3 and H3K27ac at promoter regions. We observed that histone H3 K18, K27 and K9 acetylation positively correlate with gene expression, and a conserved pattern was also reported in other organisms. Finally, we report that histone H4K20me1 is strongly linked to active genes, whereas H4K20me3 is associated with weakly expressed genes. Our analysis further shows that H4K20me1 modification levels peak at 3‟UTR regions in active genes. Thus, our analysis revealed many different aspects of histone modification patterns and their roles in transcriptional control in fission yeast.

  • 759.
    Sinha, Indranil
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Institutet.
    Buchanan, Luke
    Technische Universität Dresden, Dresden, Germany / Max Planck Institute, Dresten, Germany.
    Rönnerblad, Michelle
    Karolinska Institutet.
    Bonilla, Carolina
    Karolinska Institutet.
    Durand-Dubief, Mickael
    Karolinska Institutet.
    Shevchenko, Andrej
    Max Planck Institute, Dresten, Germany.
    Grunstein, Michael
    Geffen School of Medicine at UCLA, & the Molecular Biology Institute, Los Angeles, USA.
    Stewart, A. Francis
    Technische Universität Dresden, Dresden, Germany.
    Ekwall, Karl
    Karolinska Institutet.
    Genome-wide mapping of histone modifications and mass spectrometry reveal H4 acetylation bias and H3K36 methylation at gene promoters in fission yeast2010Ingår i: Epigenomics, ISSN 1750-1911, Vol. 2, nr 3, s. 377-393Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To map histone modifications with unprecedented resolution both globally and locus-specifically, and to link modification patterns to gene expression. Materials & methods: Using correlations between quantitative mass spectrometry and chromatin immunoprecipitation/microarray analyses, we have mapped histone post-translational modifications in fission yeast (Schizosaccharomyces pombe). Results: Acetylations at lysine 9, 18 and 27 of histone H3 give the best positive correlations with gene expression in this organism. Using clustering analysis and gene ontology search tools, we identified promoter histone modification patterns that characterize several classes of gene function. For example, gene promoters of genes involved in cytokinesis have high H3K36me2 and low H3K4me2, whereas the converse pattern is found ar promoters of gene involved in positive regulation of the cell cycle. We detected acetylation of H4 preferentially at lysine 16 followed by lysine 12, 8 and 5. Our analysis shows that this H4 acetylation bias in the coding regions is dependent upon gene length and linked to gene expression. Our analysis also reveals a role for H3K36 methylation at gene promoters where it functions in a crosstalk between the histone methyltransferase Set2(KMT3) and the histone deacetylase Clr6, which removes H3K27ac leading to repression of transcription. Conclusion: Histone modification patterns could be linked to gene expression in fission yeast.

  • 760.
    Sinha, Indranil
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi. Karolinska Institutet.
    Jemt, Elisabeth
    Göteborgs universitet.
    Durand-Dubief, Mickaël
    Baraham Institute, Cambridge, UK.
    Stålfors, Annelie
    Karolinska Institutet.
    Sanders, Steven
    Case Western Reserve university, Cleveland, USA.
    Ekwall, Karl
    Karolinska Institutet.
    Gnome wide mapping suggests different roles for H4K20me1 and H4K20me3 in gene expressionManuskript (preprint) (Övrigt vetenskapligt)
  • 761.
    Sinha, Indranil
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Wirén, Marianna
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Ekwall, Karl
    Södertörns högskola, Institutionen för livsvetenskaper. Karolinska Institutet.
    Genome-wide patterns of histone modifications in fission yeast2006Ingår i: Chromosome Research, ISSN 0967-3849, E-ISSN 1573-6849, Vol. 14, nr 1, s. 95-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have used oligonucleotide tiling arrays to construct genome-wide high-resolution histone acetylation maps for fission yeast. The maps are corrected for nucleosome density and reveal surprisingly uniform patterns of modifications for five different histone acetylation sites. We found that histone acetylation and methylation patterns are generally polar, i.e. they change as a function of distance from the ATG codon. A typical fission yeast gene shows a distinct peak of histone acetylation around the ATG and gradually decreased acetylation levels in the coding region. The patterns are independent of gene length but dependent on the gene expression levels. H3K9Ac shows a stronger peak near the ATG and is more reduced in the coding regions of genes with high expression compared with genes with low expression levels. H4K16Ac is strongly reduced in coding regions of highly expressed genes. A second microarray platform was used to confirm the 5' to 3' polarity effects observed with tiling microarrays. By comparing coding region histone acetylation data in HDAC mutants and wild type, we found that hos2 affects primarily the 5' regions, sir2 and clr6 affect middle regions, and clr6 affects 3' regions. Thus, mechanisms involving different HDACs modulate histone acetylation levels to maintain a 5' to 3' polarity within the coding regions.

  • 762.
    Siri, Troili
    Södertörns högskola, Institutionen för livsvetenskaper.
    Local Implications of Higher Global Food Prices: A Study of Poverty and Possibilities in Zambia2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The purpose of this study is to examine how the global food price crisis 2007-2008 affected poor people in Zambia. The study is supposed to find out how the high world market prices of food were transmitted to Zambia and what impacts the high prices had on the poor people in rural and urban parts of Zambia.

    The theories that are used in the paper are Amartya Sen’s theory of food entitlement, Henry Bernstein’s writings of poverty and farming and a microeconomic theory of supply and demand. The method that is used is a literature study.

    The result of the study indicated that poverty increased and poor people suffered welfare losses in Zambia due to the high prices 2007-2008. This very much as a result of that a majority of the poor people are net consumers of food, although ca 70 % of the poor people works in the agricultural sector. Higher prices did not turn out to be an incitement and a possibility for the poor farmers to raise the production. The study shows that small-scale farmers first of all need help to handle other supply-side constraints such as lack of land, information, inputs and credits, before they can increase production according to economic laws.

  • 763.
    Sjöberg, Therese
    Södertörns högskola, Institutionen för livsvetenskaper.
    En studie över det svenska utvecklingssamarbetet för barns rättigheter i Guatemala: Två organisationer med fokus på ursprungsbefolkning och utveckling sett ur ett rättighetsperspektiv2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Studien ämnar undersöka den ideologiska grunden för två organisationers arbete mot barnvåld och främjande för barns rättigheter i Guatemala. Organisationerna är IM, Individuell människohjälp och Unicef Sverige. Studiens frågeställning är även huruvida dessa idéer går att relatera till ett rättighetsperspektiv inom utveckling. Den tvådelade frågeställningen syftar till att se undersöka hur synen på rättigheternas roll betonas av det svenska utvecklingssamarbetet och därmed även påverkar synen på organisationernas barnpolitik. Som ett resultat av detta undersöks även på vilket sätt rättighetsperspektivet ser främjandet av barns mänskliga rättigheter inverkar på utveckling som helhet. Guatemala är land som trots sin ratificering av konventionen om barns rättigheter, uppvisar en alltjämt ökande våldspiral och kränkningar av barns rättigheter. Landet uppvisar även stora ekonomiska, sociala och politiska klyftor. Med detta i åtanke intar studien en fokus på en av de mest utsatta grupperna i Guatemalas samhälle; barn tillhörande ursprungsbefolkningen. Den kvalitativa flerfallstudien grundar sig på sekundärt källmaterial och har metodologiskt genomförts med en idéanalys. Här granskas idéerna som utrycks av rättighetsperspektivens främste förespråkare Amartya Sen och hans frihetsbegrepp, samt Robert Chambers syn på utvecklingens innebörd. Organisationernas ideologi relateras även till konventionen om barns mänskliga rättigheter. Då studien ser till bakomliggande idéer bakom ett utvecklingssamarbete, uppmärksammas även vilken vikt som tillskrivs ord som lyhördhet och delaktighet. Uppsatsen visar på en likritning med båda organisationernas policy och idéerna inom ett rättighetsperspektiv. Resultaten visar även på att en utvecklingsprocess, sett ur ett rättighetsperspektiv samverkar på ett direkt, såväl som på ett indirekt sätt av främjandet av barns rättigheter.

  • 764.
    Sjödin, Emma
    Södertörns högskola, Institutionen för livsvetenskaper.
    Leaking or Waterproof Organization?: Babati Town and the Current Capacity to Handle Floods2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 765.
    Sjöling, Sara
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Cowan, Don A
    University of the Western Cape, South Africa.
    Metagenomics: microbial community genomes revealed2008Ingår i: Psychrophiles: from biodiversity to biotechnology / [ed] Rosa Margesin, Franz Schinner, Jean-Claude Marx, Charles Gerday, Berlin, Heidelberg: Springer, 2008, s. 313-330Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    The rapidly expanding field of metagenomics has revolutionized the ability to analyzemicrobial communities by providing access to ‘true’ microbial diversity. This field has a broad range of applications in the areas of biodiversity, systems biology and biotechnology (Handelsman et al. 2002). As most microbial communities in soil, sediment or aquatic environments are highly complex, consisting of hundreds oreven thousands of species of which only a few have been cultured, the approaches collectively described as metagenomics, community genomics or environmental genomics have been developed to help to unlock this thus far hidden diversity. Metagenomics is therefore the application of modern genomic tools used to analyze the collective genomes of whole microbial communities (the metagenome) in an environmental sample, thereby bypassing the need for isolation or cultivation (Béjà et al. 2000; Riesenfeld et al. 2004b). Even though the tip of the microbial ice-berg has barely been scratched, this approach is rapidly increasing our knowledge of microbial genetic and functional diversity through gene/pathway discovery either by sequencing or activity-based screening strategies (Handelsman 2005).

  • 766.
    Sjöling, Sara
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Edlund, Anna
    Östersjöns döda bottnar fulla med liv2008Ingår i: HavsUtsikt, ISSN 1104-0513, nr 1, s. 12-13Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 767.
    Sjöling, Sara
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Stafford, W
    Cowan, D A
    Soil metagenomics: exploring and exploiting the soil microbial gene pool2007Ingår i: Modern soil microbiology / [ed] Jan Dirk van Elsas, Janet K Jansson, Jack T Trevors, Boca Raton: CRC Press, Taylor & Francis , 2007, s. 409-434Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 768.
    Sjöling, Sara
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Thureborn, Petter
    Den gömda och okända rikedomen2009Ingår i: HavsUtsikt, ISSN 1104-0513, nr 3, s. 8-9Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 769.
    Sjövall, Johanna
    Södertörns högskola, Institutionen för livsvetenskaper.
    Identitet och svenskhet: En diskursiv granskning av svenska läroböcker i historia2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis is concerned with how identity is connected to historical writings and what normsshapes the perspectives of history. The purpose of this study is to investigate the possibilitiesfor identification offered in history books used for history teaching. This study is concernedwith what role the nation plays and how it shapes the conception of history, with the hope ofcounteracting negative attitudes towards those not being identified as “Swedish” in the historytelling.The study was conducted through discourse analysis. The material for this analysis consistedof three history books directed towards 4-6th graders.The study shows how identity is created through putting “us” against “them”. The Swedishnation is the principal starting point of identity formation in the study material. It is in broadercontexts replaced by an western “us”. The rest of the world is only mentioned sparsely inrelation to this western “us”. The past is used to create a source of collective identity. Thenation constitutes an unquestioned base of unity. The nationalism and the history telling isconnected to ideas of social evolution. The western thinking and development is being presented as superior.

  • 770.
    Skibicki, Dominik
    et al.
    Södertörns högskola, Institutionen för ekonomi och företagande. Södertörns högskola, Institutionen för livsvetenskaper.
    Pejhman, Pourmand
    Södertörns högskola, Institutionen för ekonomi och företagande. Södertörns högskola, Institutionen för livsvetenskaper.
    Extern granskning av medicinska bilder, framtidens lösning?2010Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 771.
    Skjöldevald, Maja
    Södertörns högskola, Institutionen för livsvetenskaper.
    Small-scale farmers and the shift in the food trading paradigm: – A comparison of two rice supply chains in Babati district, Tanzania2008Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    The aim of this study is to find out the dynamics of rice supply chains and their impacts on the small-scale rice producer in Magugu village. The problem addressed in this study is the changes in the food trading paradigm and how it is shaping power relations at a local level. The empirical material in this study has been collected during a fieldtrip to the Babati district in Tanzania from the 25th of February to the 19th of March (2008). The First Mile Project (FMP) in Tanzania had the purpose to teach farmers how to build more equal and efficient supply chains and linking the producer to the consumer. A comparison between a regular rice supply chain and one involved in the FMP was made to explore how the two was forming in the changing food trade paradigm and how the farmers were adapting to this fact. Several methods were employed in this study. These include: case study method, qualitative methods, and secondary data. The results in this study was analysed with the use of the Global Value Chain (GVC) analysis and the Network theory. The conclusion was that depending on how the networks and the power relations within them, actors in the leading position in the GVC determines how the product is going to be: produced, processed, and marketed, at what time and to what price and establish requirements of the GVC. The rice farmers involved in the FMP were the once most able to adapt to the requirements of the GVC and food trading paradigm because of the cooperation among the group and good relations with other actors along the supply chain.

  • 772.
    Skoogh, Camilla
    Södertörns högskola, Institutionen för livsvetenskaper.
    Konflikten mellan människor och elefanter2008Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

    Sammanfattning

    Uppsatsen beskriver konflikten mellan elefanter och människor kring Tarangire nationalpark. Som är en park som är mycket känd för mängden elefanter som de har, så det är ett växande problem. Själva fokusen ligger på hur elefanterna förstör för de lokala befolkningen och vad som kommer hända om elefanterna får fortsätta att öka i antal som de gör nu. Uppsatsen ska undersöka vad man kan göra för att bevara det vilda djurlivet i synnerhet elefanterna, men samtidigt skydda jordbrukare mot elefanter som äter upp och förstör deras grödor.

    Men genom att befolkningen i Tanzania ökar gör det att människor flyttar allt närmare Tarangire nationalpark och dom korridorer som djuren använder för deras traditionella vandringar. Allt detta skapar stora problem genom att djurens habitat minskar, vilket resulterar i att bland annat elefanterna orsakar stora skador på jordbrukarnas fält, genom att de äter upp grödor eller trampar sönder grödorna.

    Alla jordbrukare kring Tarangire nationalpark hade detta problem och många kände en uppgivenhet eftersom ingen hjälpte dem, verken nationalparkerna eller regeringen. Jordbrukarna hade några traditionella metoder för att skrämma iväg elefanterna och några av dessa var att man gjorde ljud, eld och kastade saker. Men ibland hjälpte ingenting eftersom elefanten i fråga inte var rädd. Vilket innebar för jordbrukaren att man inte kunde göra någonting, utan man fick se på hur ens levebröd blev uppätet eller nedtrampat. För att sen ta arbete hos någon annan för att överleva.

  • 773.
    Sköld, Linda
    Södertörns högskola, Institutionen för livsvetenskaper. Södertörns högskola, Lärarutbildningen.
    ”Naturvetenskap finns ju överallt”: En kvalitativ studie av hur förskollärare på småbarnsavdelningar på Reggio Emilia inspirerade förskolor  ser på arbetet med naturvetenskap2012Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The purpose of the study was to determine the attitudes of the teachers of Reggio Emilia inspired preschools concerning the science work with children between the ages of one and three, as well as their opinions on how the physical preschool environment and the choice of materials influence their scientific work. The study was conducted in three departments of two different kindergartens. Although both kindergartens called themselves Reggio Emilia inspired, their working methods and their environments differed largely. None of them were originally built as Reggio Emilia inspired preschools. One of the kindergartens strived to design their indoor environment the same way as the preschools of Reggio Emilia are constructed, there for they were setting up different stations where the children themselves have the opportunity to explore various scientific areas. They also had their pedagogical documentation clearly visible. The other kindergarten did not have a “station mind-set” of the indoor environment and their pedagogical documentation was not visible. Their teachers claimed that their preschool was new and under construction, and that the pedagogical documentation would soon become a natural part of their activity. All three preschool teachers that were interviewed felt that it is important to work with science with children between the ages of one and three, saying that science involves many areas and is found everywhere. All preschool teachers, however, had the forest as their basis for the scientific work and it was mostly the forest and outdoor activities that were in focus in their development of educational activities.

  • 774. Slesak, Ireneusz
    et al.
    Libik, Marta
    Karpinska, Barbara
    Södertörns högskola, Institutionen för livsvetenskaper.
    Karpinski, Stanislaw
    Miszalski, Zbigniew
    The role of hydrogen peroxide in regulation of plant metabolism and cellular signalling in response to environmental stresses2007Ingår i: Acta Biochimica Polonica, ISSN 0001-527X, E-ISSN 1734-154X, Vol. 54, nr 1, s. 39-50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hydrogen peroxide (H2O2) is produced predominantly in plant cells during photosynthesis and photorespiration, and to a lesser extent, in respiration processes. It is the most stable of the so-called reactive oxygen species (ROS), and therefore plays a crucial role as a signalling molecule in various physiological processes. Intra- and intercellular levels of H2O2 increase during environmental stresses. Hydrogen peroxide interacts with thiol-containing proteins and activates different signalling pathways as well as transcription factors, which in turn regulate gene expression and cell-cycle processes. Genetic systems controlling cellular redox homeostasis and H2O2 signalling are discussed. In addition to photosynthetic and respiratory metabolism, the extracellular matrix (ECM) plays an important role in the generation of H2O2, which regulates plant growth, development, acclimatory and defence responses. During various environmental stresses the highest levels of H2O2 are observed in the leaf veins. Most of our knowledge about H2O2 in plants has been obtained from obligate C-3 plants. The potential role of H2O2 in the photosynthetic mode of carbon assimilation, such as C-4 metabolism and CAM (Crassulacean acid metabolism) is discussed. We speculate that early in the evolution of oxygenic photosynthesis on Earth, H2O2 could have been involved in the evolution of modem photosystem II.

  • 775.
    Slesgård, Sanna
    Södertörns högskola, Institutionen för livsvetenskaper.
    Fick algblomningen i Östersjön 2005 några ekonomiska effekter?: Fallet turistnäringen på Gotland2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Algblomning är en naturligt förekommande företeelse och sker i alla vatten världen över men på senare år har algblomningarna i Östersjön blivit kraftigare och utbredningen större. Då algblomningen påverkar badvattenkvaliteten negativt, kan det tänkas att det får effekt på turismnäringen i Östersjön. Syftet med denna uppsats är att studera, genom en enkätundersökning baserad på produktionsfunktionsmetoden, huruvida ett förändrat miljötillstånd som algblomning, påverkat den gotländska turistboendebranschen och deras ”produktion av attraktiva övernattningar” sommaren 2005. Resultatet visar att algblomningen inte hade någon större påverkan på företagens ”produktion av attraktiva övernattningar”. Detta kan bero på att deltagandet av enkäten var låg och resultatet blir därmed svår analyserat och ej säkerställt. Det är också intressant att totalt sett anser 57 % av alla svarande att turistbranschen påverkades negativt av algblomningen, vilket är fler än de som själva ansåg sig bli påverkade – nästan dubbelt så många. Totalt var det 35 % som ansåg sig påverkade av algblomningen totalt i undersökningen och där var det faktiskt västgruppen som ansåg sig mest påverkade på annat sätt av algblomningen med 17 % mot 13 % för östgruppen. Nästan alla som deltog i undersökningen hävdade att media blåser upp problemet algblomning och att det påvekar bilden av Gotland negativt.

  • 776.
    Slotvitskaja, Jelena
    Södertörns högskola, Institutionen för livsvetenskaper.
    Ekologiskt hållbar utveckling i kommunalt miljömålsarbete  : Hur kan en möjlig formulering av lokala miljömål underlätta kommunala verksamheter som äldreboende samt gruppboende att uppnå miljömål Giftfri miljö och God bebyggd miljö?2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    Sustainable development includes environmental, social and economic dimension, which has become an accepted concept at all levels of society. There is also a need for these dimensions to integrate with each other. To attain a sustainable development it has to be seen as a whole. The environmental objectives were established by Swedish parliament in 1999; however these objectives are only one of the steps in achieving a sustainable society. Swedish municipality are forced to use the environmental objectives for guidance in planning society. Municipalities have a responsibility to integrate environmental issues into political processes and at the same time contribute to an increase of the awareness about these issues. There is no guidance in the work with the environmental objectives and municipality have to work on the basis of their own environment and conditions.

    The aim of this essay was to study the work of implementing environmental objectives in one municipality, with the focus on the objectives four and fifteen; towards an ecological sustainable development with support of the environmental work of another municipality. The focus of the work lays on the formulation of environmental objectives four and fifteen in order for them to be achieved without difficulty.

    One conclusion is that none of the chosen environmental objectives are reached. The theoretical discussion highlights the importance of a communicative work between different participants and also information about the environmental issues on the individual level.      

    This work was considered to contribute to future research concerning municipalities work with environmental objectives. 

  • 777.
    Slotwinska, Paulina
    Södertörns högskola, Institutionen för livsvetenskaper.
    Genmodifierade grödor och dess konsekvenser: För människa och miljö i Sydamerika, USA och EU2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

    Uppsatsen behandlar GMO (genmodifierade grödor) och hur de påverkar människa och miljö i USA, Sydamerika (Argentina och Brasilien) och Europa. De geografiska områdena har valts då arealen över GMO-odlingar är störst i USA och Sydamerika samt för att mestadels av GMO exporteras till Europa. GMO-frågan har varit väldigt omdebatterad i Europa och andra delar av världen de senaste åren av miljöorganisationer, forskare och genteknikföretag. Syftet med denna uppsats är att undersöka för- och nackdelarna med genmodifierade grödor.

    Uppsatsens undersökning utgörs av två intervjuer med sakkunniga personer med skilda uppfattningar om genmodifierade grödor. I denna del behandlas även information från olika organisationer som t.ex. SNF (Svenska naturskyddsföreningen) och gmofri.se. Undersökningen genomfördes i syfte att besvara uppsatsens frågeställningar. Hur påverkas människor och miljö av genmodifierade grödor i USA, Sydamerika och Europa? Kan genmodifierade grödor lösa problemet med världssvälten? Hur förhåller man sig till GMO i olika geografiska delar av världen och varför?

    Uppsatsens resultat visar att miljöpåverkan är stor eftersom genmodifierade grödor är oförutsägbara och kan ge oväntade egenskaper. Det största miljöproblemet med GMO är påverkan av den biologiska mångfalden som sker p.g.a. spridning till naturliga växter. Människans påverkas då GMO kan bidra till allergiframkallning och även att människan kan få det svårare att bekämpa sjukdomar med hjälp av antibiotika. Människan påverkas även på andra områden än hälsan, exempelvis genom att människan förlorar kontroll över livsmedelsproduktionen då multinationella gentekniksföretag äger patent på 90 procent av all GMO. GMO är inte heller en lösning på svälten, man bör lösa svältens orsaker i första hand som bland annat krig. GMO som lösning på svält används som marknadsföring av genteknikföretag då det är ett faktum att det endast är dessa företag som tjänat på GMO hittills och majoriteten av GMO som odlas i perifera länder exporteras som foder till kärnländernas slaktdjur och för användning som biobränsle. Resultatet visar även att man vet för lite om genmodifierade grödors påverkan på miljö och framför allt på människan för att kommersialiseras.

  • 778.
    Smolarz, Katarzyna
    et al.
    Södertörns högskola, Centrum för Östersjö- och Östeuropaforskning (CBEES). Södertörns högskola, Institutionen för livsvetenskaper.
    Berger, Agata
    Long-term toxicity of hexabromocyclododecane (HBCDD) to the benthic clam Macoma balthica from the Baltic Sea2009Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 95, nr 3, s. 239-247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The world's largest brackish water sea area, the Baltic Sea, is considered to be one of the most polluted seas of the world. Many new pollutants are constantly entering the environment, such as brominated flame-retardants (BFRs). BFRs represent a group of compounds that structurally resemble hydrophobic organic contaminants, but only scarce data about their toxicity to marine organism exist. Thus, the purpose of this study was to analyze long-term in vivo cytotoxicity and genotoxicity of hexabromocyclodododecane (HBCDD) to exposed marine invertebrates using a suite of cytogenetic biomarkers. This included a set of nuclear and nucleolar characteristics and the micronucleus test. The use of those parameters reflects different mechanisms of nuclear activity regulation in cells (as a parameter of cytotoxicity) and measures subcellular processes. The induction of nuclear abnormalities (like the formation of micronuclei) was also employed here as a parameter of genotoxicity. In order to reflect the proliferative and metabolic activity of the cells the number of argylophillic nucleolar organiser regions (NORs) in interphase cells was scored. Over a period of 50 days an in vivo exposure experiment with a clam Macoma balthica and different concentrations of HBCDD (nominal concentrations of 0, 100 and 250 μg/l) with three replicates each was performed. Gill cells were used as “sentinel systems” considering specificity in metabolism, repair mechanisms, adaptative response and cell proliferation. A significant increase in nuclear and nucleolar abnormalities and in the frequency of dead cells was observed during the duration of the experiment with the highest peak occurring 10 days after exposure for nuclear abnormalities and 20–30 days after exposure for malfunction of ribosomal genes (NORs) (GLM analyses and Spearman correlation, p < 0.05). Thus, the induction of micronuclei and other nuclear abnormalities reflected the toxic potential of HBCDD to marine invertebrates while an increase in the number of NOR may also reflect adaptive responses of the system as enhanced induction of proliferative regeneration of the gill tissue

  • 779.
    Solbrig, Franziska
    Södertörns högskola, Institutionen för livsvetenskaper.
    Integrating conservation and sustainable use of biodiversity: Four Examples of Ecosystem Management Areas in Germany and Sweden2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    The loss of biodiversity is recognised as a tremendous threat to ecosystems, but its maintenance is challenging. One important issue is seen as decisive for its success: the integration of sustainable use and conservation of biodiversity that means to reconcile protective measures with different kinds of use. This study investigated management areas that explicitly emphasise this issue: UNESCO Man and Biosphere (MAB) Reserves that shall contribute to reconcile the conservation of biodiversity with its sustainable use and an initiative from the Swedish government called Regional Landscape Strategies that aims to find a balance between sustainable use and conservation on a landscape level. In three MAB Reserves in Germany and one Swedish county testing Regional Landscape Strategies semi-structured interviews were conducted. They aimed to detect the values and factors steering the decisions of biodiversity management and conservation as well as to identify obstacles for sustainable use, conservation and their integration in general. The interviews reveal that the connected terms and concepts can be interpreted in different ways and this exacerbates the work. Furthermore, the study detects some issues that can facilitate the integration of sustainable use and conservation of biodiversity in the respective areas and discussed their applicability on a larger scale. Examples are the establishment of a kind of forum involving local affected stakeholders and the creation of a connection point mediating the different sectors within the administration. These aspects could help to design the management of biodiversity more sustainable if they would be part of the mainstream management practises. Regarding the state of biodiversity that shall be achieved or maintained it can be mentioned that different factors and values steer the decisions; intrinsic values are underlying, but further issues seem crucial: practicability of the respective land use, aesthetic values, a high resilience of the system as well as the near-natural states.

  • 780.
    Souter, Petra
    Södertörns högskola, Institutionen för livsvetenskaper. Stockholms universitet, Zoologiska institutionen.
    Causes and consequences of spatial genetic variation in two species of scleractinian coral in East Africa: Levels of genetic differentiation and intraspecific diversity of Pocillopora damicornis and Platygyra daedalea2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The work presented in this thesis is a study of the spatial genetic structure of two species of scleractinian corals, Pocillopora damicornis and Platygyra daedalea. The overall objective was to investigate the current capacity of MPAs to preserve and restore coral reefs and to contribute information to improve management decisions. Samples were taken from 11 sites along the coast of Kenya. In addition P. daedalea was sampled from one site on each of the islands of Unguja (Zanzibar archipelago) and Mafia in Tanzania.

    Populations of P. daedalea were largely panmictic within two lagoonal clusters. Samples obtained from two off-shore sites were more similar to the samples from the island samples in Tanzania than they were to proximal lagoonal samples. Off-shore and island samples were also significantly more genetically diverse in both the level of heterozygosity and allelic richness. Migration predominantly occurs from off-shore and island reefs toward the lagoonal reefs. The investigated populations of P. damicornis exhibited limited genetic neighbourhoods and highly localised recruitment and a significant pair-wise differentiation was found between a majority of the sampling sites. These results are probably a cause of the genetic bottleneck caused by the high mortality of this species during the 1998 coral bleaching event and reflects subsequent founder events and variable recruitment patterns, causing genetically distinct populations.

    P. damicornis also displayed plastic reproduction, with some sites being dominated by large numbers of identical multilocus genotypes. The clonal colonies showed signs of being genotypcially distinct as they were all found to be homozygotes for a specific allele at one of the microsatellite loci. Due to the decreased genotypic diversity, associated with the high rate of clonal reproduction, the level of genetic diversity and allelic richness tended to be lower at unmanaged reefs. Also, the probability of encountering clonally produced individuals was significantly greater on unprotected reefs compared with protected reefs.

    Canonical discriminant analysis of measurements of ten skeletal characters identified two distinct morphological types of P. daedalea. Analysis of molecular variance showed that morphotype explained a larger proportion of the genetic divergence than did the geographic distribution of sites sampled within MMP. However, phylogenetic analysis of rRNA sequences showed no evidence of sequence divergence, neither between morphotypes nor between samples of P. daedalea from MMP and samples of Platygyra sinensis from Hong Kong.

    In summary, these data demonstrate the importance of incorporating multiple species and aspects when addressing the issue of connectivity and its implications for management. P. damicornis would benefit from localised management efforts to preserve its genotypic diversity, whereas P. daedalea would benefit from larger reserves to minimise the risk of loosing rare alleles through genetic drift which would further reduce its genetic diversity on lagoonal reefs. It also brings the subject of morphological characteristics and local adaptation into focus by revealing possible genetic divergence between two morphotypes of P. daedalea and two reproductive modes in P. damicornis.

  • 781.
    Souter, Petra
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Grahn, Mats
    Södertörns högskola, Institutionen för livsvetenskaper.
    Higher prevalence of clonal reproduction in the coral Pocillopora damicornis on reefs outside marine protected areas in KenyaManuskript (preprint) (Övrigt vetenskapligt)
  • 782.
    Souter, Petra
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper. Australian Inst Marine Sci, Townsville, Australia.
    Grahn, Mats
    Södertörns högskola, Institutionen för livsvetenskaper.
    Spatial genetic patterns in lagoonal, reef-slope and island populations of the coral Platygyra daedalea in Kenya and Tanzania2008Ingår i: Coral reefs (Print), ISSN 0722-4028, E-ISSN 1432-0975, Vol. 27, nr 2, s. 433-439Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Considering the rapid degradation of coral reefs, it is becoming increasingly important to assess factors such as levels of intraspecific genetic diversity and degree of connectivity between populations and reefs. In this study, five DNA microsatellite markers were used to infer migration patterns and levels of genetic diversity in ten populations of the faviid coral Platygyra daedalea along the coast of East Africa. Populations from reef-slopes and offshore islands had significantly greater genetic diversity, measured as expected heterozygosity and allelic richness than those of inshore lagoonal reefs. A combination of F-statistics and individual assignment tests indicated moderate to high levels of gene flow among lagoonal populations, and less migration between lagoonal sites and the reef-slope and island sites. These results suggest that reef-slope and island reefs could be important reservoirs of genetic diversity for this coral species.

  • 783.
    Souter, Petra
    et al.
    Södertörns högskola, Institutionen för livsvetenskaper.
    Henriksson, Oskar
    Södertörns högskola, Institutionen för livsvetenskaper.
    Grahn, Mats
    Södertörns högskola, Institutionen för livsvetenskaper.
    Limited migration and significant population sub-division in the coral Pocillopora damicornis on reefs along the coast of KenyaManuskript (preprint) (Övrigt vetenskapligt)
  • 784. Souter, Petra
    et al.
    Henriksson, Oskar
    Södertörns högskola, Institutionen för livsvetenskaper, Biologi. Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Olsson, Niklas
    Södertörns högskola, Institutionen för livsvetenskaper.
    Grahn, Mats
    Södertörns högskola, Institutionen för livsvetenskaper, Biologi. Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap.
    Patterns of genetic structuring in the coral Pocillopora damicornis on reefs in East Africa.2009Ingår i: BMC Ecology, ISSN 1472-6785, E-ISSN 1472-6785, Vol. 9, s. 19-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study showed that population differentiation in P. damicornis varied over spatial scales and that this variability occurred at both evolutionary and ecological time scales. This paradox is discussed in light of stochastic recruitment and small scale population structures found in other species of coral. The study also identifies potential source reefs, such as those within Mnemba Conservation area near Zanzibar and genetically isolated reefs such as those within Malindi Marine National Park and Reserve in northern Kenya.

  • 785.
    Srebrenikovic, Amir
    Södertörns högskola, Institutionen för livsvetenskaper.
    Geografi på gott och ont: En studie om kriminella och polisens användning av geografiska förutsättningar2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

    Undersökningen behandlar hur kriminella personer och polisen använder sig av geografiska förutsättningar i sina respektive verksamheter. Hur de först kartlägger objekt i sin omgivning för att sedan välja hur de ska agera. Kriminella personer och polisen undersöks för att visa hur aktörer, på olika sida om lagen, möter liknande geografiska förutsättningar fast upplever dem på olika sätt. Avslutningsvis återges deras inställning till att först kartlägga objekt i sin omgivning innan de agerar. Undersökningen skildrar hur aktörer subjektivt upplever objektiva föremål i sin omgivning på olika sätt, beroende på deras avsikter. 

    Kriminella personer planerar ett brott genom att först kartlägga sin omgivning. Det leder till att de sedan kan avgöra hur de ska agera på brottsplatsen. De beger sig till brottsplatsen en tid innan brottet ska utföras. På brottsplatsen undersöker de människors dagliga rutiner och hur objekt som exempelvis byggnader är placerade, för att kunna underlätta deras brott.  De kriminella har angett vilken tid på dygnet ett brott är som mest gynnsamt för dem. Om de inte kan utföra ett brott under en särskild tid ökar risken för att gripas. Objekt i en omgivning kan skapa tillfällen och försvåra för kriminella att genomföra brott. Deras erfarenhet bidrar till att hitta tillfällen som lämpar sig för brott i en omgivning. Svårigheter anser de vara andra människor som befinner sig på en brottsplats och väderförhållanden.

    I polisens arbete kartläggs objekt i omgivningen utförligt, eftersom de inte vill riskera att skada andra poliser, misstänkta eller allmänheten, när de ska agera i arbetet. På en brottsplats försöker de säkra bevismaterial beroende på brottsplatsens förutsättningar. Polisen vill göra ett gripande på säkrast möjliga sätt, i annat fall kan en polisaktion komma att avbrytas. Det kan handla om att gripa en misstänkt under en särskild tid på dygnet. Under ett spaningsarbete ska enskilda poliser själva kartlägga sin omgivning och avgöra hur en förflyttning ska ske. Polisspanare måste ständigt förnya och omvärdera sin omgivning. Både polisen och kriminella anser att de inte kan utföra respektive arbete utan att först ta hänsyn åt de objekt som finns i en omgivning. De resonerar om varandras agerande och uppfattar liknande objekt i omgivningen. Dessa upplever de sedan på olika sätt, till följd av deras avsikter i arbetet.

  • 786. Srivastava, R.
    et al.
    Kitambi, Satish Srinivas
    Södertörns högskola, Institutionen för livsvetenskaper.
    Goyal, A.
    In silico analysis of thioredoxins and glutaredoxins2005Ingår i: Journal of Plant Biochemistry and Biotechnology, ISSN 0971-7811, E-ISSN 0974-1275, Vol. 14, nr 2, s. 121-126Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thioredoxins (TRXs) and glutaredoxins (GRXs) are ubiquitous small redox proteins belonging to the thioredoxin (TRX) superfamily. They regulate several cellular functions via mediating a dithiol/disulphide exchange in target proteins. Thioredoxins have been classified into several subgroups based on their structural homologs. In an attempt to identify thioredoxin proteins which have not been characterized, an EST database survey of Lycopersicon esculentum, Glycine max, Helianthus annus, Secale cereale, Solanum tuberosum, Apis mellifera ligustica, Oncorhynchus mykiss, Salmo salar, and whole genome survey for Drosophila melanogaster, Rattus norvegicus and Caenorhabditis briggsae was performed. Several glutaredoxin and glutaredoxin-like proteins from Ricinus communis, Vercinia fordii, Lycopersicon esculentum, Tilia platyphyllos, Populus tremuloides, Triticum aestivum and Oryza sativa were also characterized. The deduced amino acid sequences were aligned and phylogenetic trees were constructed to determine the consensus sequences and for establishing interrelationships amongst the new and established thioredoxin and glutaredoxins. Based on the alignments, proteins were designated to their respective classes and subcellular localization predictions were used to predict their possible site of actions. In silico analysis has identified several new thioredoxins, glutaredoxins and related proteins and provided insight into their evolutionary relationships.

  • 787. Stacey, N. E.
    et al.
    Van der Kraak, G. J.
    Olsén, K. Håkan
    Södertörns högskola, Institutionen för livsvetenskaper, Miljövetenskap. Södertörns högskola, Institutionen för livsvetenskaper, Biologi.
    Male primer endocrine responses to preovulatory female cyprinids under natural conditions in Sweden2012Ingår i: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 80, nr 1, s. 147-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigated two related aspects of male-female reproductive interactions in the family Cyprinidae: (1) whether ovulating female rudd Scardinius erythrophthalmus (subfamily Leuciscinae) induce endocrine and gonadal priming responses in conspecific males, a phenomenon which has been described only in species from the subfamily Cyprininae such as goldfish, Carassius auratus, crucian carp Carassius carassius and common carp, Cyprinus carpio and (2) whether the stimuli mediating these responses are species-specific. Field studies of three sympatric European cyprinids, two leuciscins (S. erythrophthalmus and white bream Blicca bjoerkna) and one cyprinin (C. carassius), were conducted on fishes captured in Sweden in the spawning season and held in net pens under natural conditions. As previously reported in C. carassius, male S. erythrophthalmus increased milt (sperm and seminal fluid) volume and plasma concentrations of the sperm maturation hormone 4-pregnen-17,20 beta-diol-3-one (17,20 beta-P) when they were held with female S. erythrophthalmus induced to ovulate by injection of Ovaprim (GnRH analogue plus dopamine antagonist). Male S. erythrophthalmus had larger milt volumes than male C. carassius prior to and following exposure to ovulatory conspecifics, but exhibited a smaller proportional milt increase in response to stimulation, suggesting species differences in sperm allocation at spawning. The presence of female S. erythrophthalmus and B. bjoerkna did not affect milt volumes of C. carassius under two experimental conditions: (1) ovulating S. erythrophthalmus and B. bjoerkna did not increase the milt volumes of C. carassius and (2) S. erythrophthalmus and B. bjoerkna did not interfere with the milt volume increase induced in male C. carassius by ovulating conspecifics. These results suggest that, as in C. auratus, C. carassius and C. carpio (subfamily Cyprininae), female S. erythrophthalmus (subfamily Leuciscinae) release a preovulatory pheromone that exerts priming effects on male hormones and sperm allocation. The findings also indicate that C. carassius discriminate between the reproductive odours of conspecifics and heterospecifics.

  • 788.
    Stenberg, Anna
    Södertörns högskola, Institutionen för livsvetenskaper.
    Vad gör och vad kan försvarsmakten göra för en hållbar utveckling?: En studie av försvarsmaktens arbete för en hållbar utveckling med avseende på utbildning.2007Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [sv]

    Genom våra val och beteendemönster påverkar vi människor varandra, både lokalt och globalt. Medvetenheten ökar och vi ser idag en växande oro för effekten av detta.

    Världssamfundet har enats om att sträva efter en hållbar utveckling. Åren 2005-2014 har av Förenta Nationerna (FN) blivit utsedda till år där man ska verka för en hållbar utveckling genom utbildning.

    Sverige har fört in hållbar utveckling i miljöbalken och landets miljöpolitik skall sträva efter densamma. Försvarsmakten har ett ansvar för den ekologiskt hållbara utvecklingen inom sin sektor, försvarssektorn. Som myndighet når de ut till många genom just utbildning då cirka 8500 värnpliktiga utbildas per år, därtill tillkommer de anställda.

    Uppsatsen undersöker hur försvarsmakten uttalat arbetar för en hållbar utveckling och hur utbildningssituationen, i fråga om hållbar utveckling, ser ut. Därefter har ett utbildningsförslag för en utbildning för hållbar utveckling utformats.

    Studien har genomförts genom litteraturstudier, intervjuer samt deltagande på ett forsknings- och utvecklingsseminarium.

    Försvarsmakten har tidigare inte arbetat så mycket uttalat för en hållbar utveckling. Gällande utbildning där hållbar utveckling tas upp, sker detta bara för anställda på det förbandet som undersöktes. Följaktligen når detta inte alla verksamma inom myndigheten. En utbildning för hållbar utveckling skulle kunna ske som en utbildningscykel, på cirka elva månader, där kunskap om begreppet och dess innebörd ges, men också hur deltagarnas val och beteenden påverkar deras omgivning.

    Om en hållbar utveckling ska ske måste alla ta ansvar för den och där måste staten och myndigheterna ta täten och verka föredömligt. Arbetet bör ske med tydliga mål och riktlinjer så att alla strävar efter samma mål.

  • 789.
    Stensson, Erica
    Södertörns högskola, Institutionen för livsvetenskaper.
    The social stratification of albinos in Tanzania: a case study from Babati2008Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    The study investigates the social stratification of albinos in Tanzania. This is done by conducting a case study in Babati and decoding and generalising the attitudes in a national context. This is combined with a litterateur study which has been made analysing the attitudes towards albinos in the media. The study has used a critical as well as continental discourse analysis and decoded the data by using the theories of social constructivism and of stigma. Semi-structured interviews as well as a litterateur study was conducted.

    The result proved that the albinos in Tanzania are stigmatised in the society and that people treat them based on myths and preconceptions. This stratification sometimes goes as far as to murders and mutations of albinos. The respondents as well as the media and government refer to the lack of education as the main cause behind the killings of albinos. A combination of the myths about albinos and the lack of education is the reasons that are accurate when analysing the reasons behind the ongoing murders.

     

     

     

  • 790. Stenvall, Jörgen
    et al.
    Fierro-Gonzalez, Juan Carlos
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Swoboda, Peter
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Saamarthy, Karunakar
    Cheng, Qing
    Cacho-Valadez, Briseida
    Arner, Elias S. J.
    Persson, Olof P.
    Miranda-Vizuete, Antonio
    Tuck, Simon
    Selenoprotein TRXR-1 and GSR-1 are essential for removal of old cuticle during molting in Caenorhabditis elegans2011Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 108, nr 3, s. 1064-1069Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Selenoproteins, in particular thioredoxin reductase, have been implicated in countering oxidative damage occurring during aging but the molecular functions of these proteins have not been extensively investigated in different animal models. Here we demonstrate that TRXR-1 thioredoxin reductase, the sole selenoprotein in Caenorhabditis elegans, does not protect against acute oxidative stress but functions instead together with GSR-1 glutathione reductase to promote the removal of old cuticle during molting. We show that the oxidation state of disulfide groups in the cuticle is tightly regulated during the molting cycle, and that when trxr-1 and gsr-1 function is reduced, disulfide groups in the cuticle remain oxidized. A selenocysteine-to-cysteine TRXR-1 mutant fails to rescue molting defects. Furthermore, worms lacking SELB-1, the C. elegans homolog of Escherichia coli SelB or mammalian EFsec, a translation elongation factor known to be specific for selenocysteine in E. coli, fail to incorporate selenocysteine, and display the same phenotype as those lacking trxr-1. Thus, TRXR-1 function in the reduction of old cuticle is strictly selenocysteine dependent in the nematode. Exogenously supplied reduced glutathione reduces disulfide groups in the cuticle and induces apolysis, the separation of old and new cuticle, strongly suggesting that molting involves the regulated reduction of cuticle components driven by TRXR-1 and GSR-1. Using dauer larvae, we demonstrate that aged worms have a decreased capacity to molt, and decreased expression of GSR-1. Together, our results establish a function for the selenoprotein TRXR-1 and GSR-1 in the removal of old cuticle from the surface of epidermal cells.

  • 791.
    Stephenson-Möller, Klara
    Södertörns högskola, Institutionen för livsvetenskaper.
    Klimat & Patriarkat: Genusgeografi i Huddinge2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The essay deals with gender aspects on climate change adaption. The aspects consist of the fact that women in Sweden drive cars less than men, and that women in the developing world are more affected by natural disasters arising from global warming. This study was carried out in the municipality of Huddinge, a suburb to Stockholm, by interviewing one Agenda 21 coordinator, one planner and one student in genderstudies. I also attended a meeting in the Committee for built environment in the Huddinge Municipality, to ask the politicians questions and observe gender structures during the meeting. The results also consist of a search for gender-related words in the documents used in the essay.

    The results are analysed using ecofeminsim, a theory that connects woman subordination and environmental destruction. According to ecofeminists these issues are both caused by patriarchal structures formed in western society during the scientific revolution. Ecofemisnim is of interest for geography, as both these deals with theories connecting processes on global issues. To solve the climate change-problem, geography could play an important role in connecting natural science with social science.

    The results are that there are insights into both gender awareness issues and into climate adaption issues among the civil servans in Huddinge Municipality, but these two issues are not connected to each other. The work carried out to adapt the municipality to a warmer climate consists of working towards more walking, cycling and public transport. It is important to consider gender issues in climate change policies on all levels.

  • 792.
    Stockhaus, Karolina
    Södertörns högskola, Institutionen för livsvetenskaper.
    Polish aesthetic medicine market in the context of Swede's beauty tourism: High-quality, low-cost services towards demanding Swedish patients2012Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis concerns Swedes’ medical tourism to Poland with an indication of  travelling for beauty treatments. Its goal is to study Swedes travelling to Poland because of aesthetic medicine purposes. Trips with medical background, e.g. surgeries, dental treatments or spa/wellness tourism were not taken into account in this assignment. However, in many aspects, some of this data were also included because of the unavailability of more precise sources. The aim has also been to try to reach an insight in what kind of factors and motivations cause that more and more Swedes choose to seek medical help in Poland. The goal has been also to show how the future of this kind of tourism could look like. The study is based on qualitative interviews with clinics and medical centres performing those treatments and patients/customers with such an experience. The theoretical framework concerns laws and regulations, also personal motivations and needs. I came to the conclusion that there are several reasons for people to travel to Poland for medical services: relative low costs of treatment, high quality of service and technology, short waiting periods, insignificant cultural differences and geographical proximity of both of the countries.

  • 793. Strålfors, Annelie
    et al.
    Walfridsson, Julian
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Bhuiyan, Hasanuzzaman
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    Ekwall, Karl
    Södertörns högskola, Institutionen för livsvetenskaper, Molekylärbiologi.
    The FUN30 Chromatin Remodeler, Fft3, Protects Centromeric and Subtelomeric Domains from Euchromatin Formation2011Ingår i: PLoS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 7, nr 3, artikel-id e1001334Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The chromosomes of eukaryotes are organized into structurally and functionally discrete domains. This implies the presence of insulator elements that separate adjacent domains, allowing them to maintain different chromatin structures. We show that the Fun30 chromatin remodeler, Fft3, is essential for maintaining a proper chromatin structure at centromeres and subtelomeres. Fft3 is localized to insulator elements and inhibits euchromatin assembly in silent chromatin domains. In its absence, euchromatic histone modifications and histone variants invade centromeres and subtelomeres, causing a mis-regulation of gene expression and severe chromosome segregation defects. Our data strongly suggest that Fft3 controls the identity of chromatin domains by protecting these regions from euchromatin assembly.

  • 794.
    Sundholm, Cecilia
    Södertörns högskola, Institutionen för livsvetenskaper.
    Educate a woman - and you will educate an entire nation?: A comparative study between rural and urban areas on the perception of education and empowerment of women2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis aims to investigate if there are differences between men and women in rural and urban areas on perception of women empowerment. The focus is on girls’ education and development in a post – colonial country. Semi structured, qualitative interviews were conducted in Babati district, Tanzania in February 2011. In order to obtain as much useful information and data as possible several research questions were focused on during the fieldwork. These were: What is the perception on empowerment of women, according to local men and women in rural and urban Babati? , How does a gender gap in school affect development, according to local men and women in rural and urban Babati? , Is the patriarchal heritage an obstacle for development and gender equality, according to local men and women in rural and urban Babati? , Why are urban areas more equal than rural areas, according to local men and women in rural and urban Babati?

    The conclusion is that people in rural and urban areas are very similar in their opinions’ of empowerment of women and education for girls. The traditional social and cultural structures are often obstacles for development.

  • 795.
    Sundin, Charlotta
    Södertörns högskola, Institutionen för livsvetenskaper.
    Risker med GMO i jordbruket2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The world is growing more and more genetically modified (or engineered) crops (GM crops). In Argentina farmers grow almost only GM soy, and no conventional soy. It is a controversial subject, since genetic engineering has many advocates and critics. The positive sides of GM crops are that it can create higher yields and incomes for the farmers. Those are the main objects of growing GM crops. Critics, on the other hand, say that GM crops have bad effects on the environment, and the risks could be too high. For example GM crops can spread to neighboring farms, where organic crops are growing. Many scientists claim that nobody really have enough knowledge of the effects of growing GM crops, and therefore thorough risk assessments are needed to examine the effects and possible risks of growing GM crops before starting to grow them. Politicians, too often, make decisions on false scientific grounds, when they claim that genetic engineering is a safe and precise method. The large corporations developing GMOs are heavily influencing political decision making. Scientists have studied the genetic engineering process and the results show that the method is not precise. It is difficult to know exactly what gene is transferred, and where it ends up. It is also important to discuss the precautionary principle in the decision making process.

  • 796.
    Svallhammar, Stig
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Den oslagsbara Roslagsbanan2011Ingår i: Spår : årsbok, ISSN 0283-6483, s. 35-50Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 797.
    Svallhammar, Stig
    Södertörns högskola, Institutionen för livsvetenskaper.
    I väntan på tunnelbanan: kollektivtrafikutbyggnad och bebyggelseexploatering i Stockholm2008Bok (Övrigt vetenskapligt)
  • 798.
    Svallhammar, Stig
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Järnvägsdöden – ett faktum?2011Ingår i: Spår : årsbok, ISSN 0283-6483, s. 152-158Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 799.
    Svallhammar, Stig
    Södertörns högskola, Institutionen för livsvetenskaper, Geografi.
    Magplask eller svanhopp i San Francisco?: spårtrafiksystem, kabelspårväg och planeringskatastrofen BART2010Ingår i: Geografiska Notiser, ISSN 0016-724X, nr 4, s. 187-196Artikel i tidskrift (Övrigt vetenskapligt)
  • 800.
    Svallhammar, Stig
    Södertörns högskola, Institutionen för livsvetenskaper.
    [Recencion av] Brandt, Backa Fredrik, Botniabanan. Förväntningar i tid och rum på regionalutveckling och resande.2008Ingår i: Svensk Geografisk Årsbok, ISSN 0081-9808, Vol. 81/84, s. 115-121Artikel, recension (Övrigt vetenskapligt)
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