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  • 151. Benach, J
    et al.
    Filling, C
    Oppermann, U C T
    Roversi, P
    Bricogne, G
    Berndt, Kurt D
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institutet.
    Jörnvall, H
    Ladenstein, R
    Structure of bacterial 3 beta/17 beta-hydroxysteroid dehydrogenase at 1.2 angstrom resolution: A model for multiple steroid recognition2002In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 41, no 50, p. 14659-14668Article in journal (Refereed)
    Abstract [en]

    The enzyme 3beta/17beta-hydroxysteroid dehydrogenase (3beta/17beta-HSD) is a steroid-inducible component of the Gram-negative bacterium Conramonas testosteroni. It catalyzes the reversible reduction/ dehydrogenation of the oxo/beta-hydroxy groups at positions 3 and 17 of steroid compounds, including hormones and isobile acids. Crystallographic analysis at 1.2 Angstrom resolution reveals the enzyme to have nearly identical subunits that form a tetramer with 222 symmetry. This is one of the largest oligomeric structures refined at this resolution. The subunit consists of a monomer with a single-domain structure built around a seven-stranded beta-sheet flanked by six alpha-helices. The active site contains a Ser-Tyr-Lys triad, typical for short-chain dehydrogenases/reductases (SDR). Despite their highly diverse substrate specificities, SDR members show a close to identical folding pattern architectures and a common catalytic mechanism. In contrast to other SDR apostructures determined, the substrate binding loop is well-defined. Analysis of structure-activity relationships of catalytic cleft residues, docking analysis of substrates and inhibitors, and accessible surface analysis explains how 3beta/17beta-HSD accommodates steroid substrates of different conformations.

  • 152.
    Bengtsson, Ellen
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Media Technology.
    Hoff, Isabelle
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Media Technology.
    Digitalisering av brädspel: Hur automation av spelmekanik kan förändra sociala interaktioner vid spelande2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Enjoyment and social interaction are closely connected, and board games can be synonymous with both of these things. Board games and digital versions of those games are often used in parallel, which offers a unique position of inquiry. Automation is a tool commonly used in the creation of digital board games, but how does it affect the sociality and how does it differ from physical board games? This is the question that this paper explores through an observational study of the game Ticket to Ride, both in its original, physical form as well as its digital counterpart. Two groups of players were recorded while playing both versions of the game in a different order. Throughout the observation of these game sessions, seven different game mechanics have been used as the lens to determine how the difference in social interaction is connected to the game itself. These game mechanics were turn-taking (time), game surface (space), object (state), actions (strategy), rules (automation), bookkeeping and chance, but social interactions unrelated to the game were also examined. Two of the seven game mechanics turned out to have the most effect on social interaction in the different versions of the game; rules and turn-taking. These two mechanics were important to the learning of the game and for maintaining focus throughout the game.

  • 153.
    Bengtsson, Joakim
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Nyberg, Jessica
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Vad i den grafiska spelmiljön påverkar spelarens problemlösning i spelet Brothers: A tale of two sons?2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här studien undersöker hur miljön i spelet Brothers: A tale of two sons (Starbreeze Studios, 2013) tolkas av spelarna. Studien fokuserar på spelmiljön och hur grafik med interagerbara objekt tolkas och hur spelaren lägger märke till objekten. En kvalitativ undersökning genomfördes där fyra personer intervjuades. Semi-strukturerad intervjuform användes och varje spelare fick testa utvalda scener ur spelet under observation. Spelet har fokus på problemlösning och det är inte alltid tydligt vad spelaren ska göra. Många andra spelutvecklare gör interagerbara objekt enkla att se genom att särskilja dem från andra objekt, genom highlights och iögonfallande färger. Målet med studien var att undersöka vilka objekt spelaren tolkar som interagerbara och hur dessa objekt utmärker sig visuellt jämfört med andra grafiska element. Genom intervjuer och observationer, blev slutsatsen att den grafiska miljön hade påverkan på spelarna, en del objekt var mer utmärkande än andra att de skulle användas som nyckelobjekt för problemlösning. Objekt som var avvikande och hade unika former som särskilde sig från bakgrunden var lättare att uppfatta som interagerbara objekt.

  • 154. Bensch, Staffan
    et al.
    Grahn, Mats
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Müller, Nils
    Gay, Laurene
    Åkesson, Susanne
    Genetic, morphological, and feather isotope variation of migratory willow warblers show gradual divergence in a ring.2009In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 18, no 14, p. 3087-96Article in journal (Refereed)
    Abstract [en]

    The circular distribution of the willow warbler Phylloscopus trochilus around the Baltic Sea shares many features with the classic examples of ring species; however, the system is much younger. It has previously been shown that a secondary contact zone is located in central Scandinavia, where there are narrow clines for several morphological traits coincident with a migratory divide. Here we analyse multiple traits and genes from > 1700 males captured on breeding territories at 77 sites spread around the Baltic Sea to test the following hypothesis. If the secondary contact zone in Scandinavia is a result of divergence in two allopatric refuge populations during the last glaciation, we expect to find a similar secondary contact zone somewhere else around the circular distribution. Our results show that the trait clines were wider and displaced from each other along the eastern side of the Baltic Sea. Analyses of 12 microsatellite loci confirmed that the genome is very similar between the terminal forms (F(ST) = 0). Two AFLP-derived markers filtered out from a genomic scan instead appear to be maintained by selection. These markers exhibited steep clines at the secondary contact zone in Scandinavia, but as for the phenotypic traits, had vastly different cline centres east of the Baltic Sea. The trait clines along the ring distribution outside the Scandinavian secondary contact zone thus seem to have been shaped by independent action of selection or drift during the process of postglacial colonization.

  • 155.
    Benulic, Kajsa-Stina
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    A Beef with Meat: Media and Audience Framings of Environmentally Unsustainable Production and Consumption2016Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The aim of this thesis is to identify potential routes of participation in environmentally sustainable changes of the Swedish meat production and consumption. Changes are needed as meat production and consumption have been linked to serious environmental problems, such as climate change, biodiversity loss, and land use change. Scientists, international organizations, and Swedish government authorities have identified individual consumer responsibility as key in making that change happen. The public is to be informed and educated to make more environmentally sustainable choices as meat consumers, and become more supportive of policy instruments. This strategy, which mirrors the dominant approach to solving environmental problems, is suggested by government authorities despite their suspicion that media should have made most Swedes aware of the environmental impacts of meat.

    In this thesis potential participatory routes are identified through the analysis of Swedish news media and audience framings of meat production and consumption. Media framing is studied as an important source of information, and perhaps motivation, crucial in the individualized consumer responsibility approach. The media framing is studied through content analysis of mainstream and alternative radical newspapers. The audiences’ framing of meat may be influenced by media, but also by their everyday experiences, beliefs, values, and opinions. Focus group discussions with reception elements are the methods used for studying how audiences frame meat and use media in the process. The concept of participation is broadened to include passive and active forms to capture in which roles individuals consider to contribute to changing meat production and consumption. It is not self-evident that routes to change must include individual participation, since responsibility may be attributed to other actors, both by media and their audiences.

    The results imply only participatory route supported by media and audience framing. It is the one that mirrors the individualized consumer responsibility approach to solving environmental problems. The major barrier to the route is the audiences’ perceived inability to act. In an alternative route supported by both media and audience framing, state centered actors are made responsible for enforcing change. Here, the major barrier is the perceived unlikeliness of powerful actors assuming responsibility. Audiences construct no citizen roles for themselves to participate in. Neither does media, who only address audiences as consumers. Based on these findings it is suggested that the outlook for the individualized responsibility approach to making meat production and consumption environmentally sustainable is gloomy. At least if it the approach is to continuously rely on the information and motivation offered by media.

  • 156. Berg, H
    et al.
    Francis, J
    Souter, Petra
    Södertörn University, Avdelning Naturvetenskap.
    Support to marine research for sustainable management of marine and coastal resources in the Western Indian Ocean2002In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 31, no 7-8, p. 597-601Article in journal (Refereed)
  • 157. Berg, Mikko
    et al.
    Marttila, Topias
    Kaipainen, Mauri
    Kojo, Ilpo
    Exploring Political Agendas with Advanced Visualizations and Interface Tools.2006In: e-Service Journal, ISSN 1528-8226, E-ISSN 1528-8234, Vol. 4, p. 47-63Article in journal (Refereed)
    Abstract [en]

    With Web-based e-services called "election engines," citizens can search for and compare candidates in local and national elections using issue-based questionnaires. The results of such services are generally in the form of search engine lists. However, data on political issues andagendas is very complex, i.e., highly multidimensional. Hence, we argue that relevant votingdecisions should not be based on simple search engine results, but on more encompassing cognitive operations. In our project, the service was redesigned to extend the function from a meresearch engine to a navigation toolset with real-time feedback. Two types of visualization components, a similarity map and sector diagrams, help citizens to make sense of multidimensional political spaces by facilitating exploration at will. As the result of an extended researchproject, our redesigned service was published by a major commercial broadcasting company forthe Finnish EU elections in June 2004 and in local elections in October 2004. 

  • 158. Berger, Juerg
    et al.
    Senti, Kirsten-Andre
    Senti, Gabriele
    Södertörn University, School of Life Sciences. Karolinska Institute.
    Newsome, Timothy P.
    Åsling, Bengt
    Dickson, Barry J.
    Suzuki, Takashi
    Systematic identification of genes that regulate neuronal wiring in the Drosophila visual system2008In: PLoS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 4, no 5, p. Online-Article in journal (Refereed)
    Abstract [en]

    Forward genetic screens in model organisms are an attractive means to identify those genes involved in any complex biological process, including neural circuit assembly. Although mutagenesis screens are readily performed to saturation, gene identification rarely is, being limited by the considerable effort generally required for positional cloning. Here, we apply a systematic positional cloning strategy to identify many of the genes required for neuronal wiring in the Drosophila visual system. From a large-scale forward genetic screen selecting for visual system wiring defects with a normal retinal pattern, we recovered 122 mutations in 42 genetic loci. For 6 of these loci, the underlying genetic lesions were previously identified using traditional methods. Using SNP-based mapping approaches, we have now identified 30 additional genes. Neuronal phenotypes have not previously been reported for 20 of these genes, and no mutant phenotype has been previously described for 5 genes. The genes encode a variety of proteins implicated in cellular processes such as gene regulation, cytoskeletal dynamics, axonal transport, and cell signalling. We conducted a comprehensive phenotypic analysis of 35 genes, scoring wiring defects according to 33 criteria. This work demonstrates the feasibility of combining large-scale gene identification with large-scale mutagenesis in Drosophila, and provides a comprehensive overview of the molecular mechanisms that regulate visual system wiring.

  • 159.
    Berger, Tony
    et al.
    Södertörn University College, School of Communication, Media and it.
    Törnqvist, Carl
    Södertörn University College, School of Communication, Media and it.
    EmoWheel: En metodutveckling för utvärdering av emotionellt engagemang2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a study of how emotional engagement can be measured and be taken into account in the development of websites. We believe that emotions become relevant only when viewed in correlation to how users experiencing a webpage. In this study, we developed a tool for use together with user tests where the information about the user's emotional engagement can add new value to the evaluation. The tool allows the user to mark, on the website, his/her emotions and level of engagement represented by colored circles, generating quantiative data on how users feel about the website. The tool is part of a method for evaluating the emotional engagement that we have developed which consists of user testing supported by the tool and accompanied by interviews.

  • 160.
    Bergfeldt, Vendela
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Microbes that never sleep: A multidisciplinary study of the antibiotic resistance management in Sweden2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The hypotheses of this study are that reduction and rational usage of antibiotics reduces development of antibiotic resistance. In Sweden, the trends do not follow this pattern. Despite a decrease in prescriptions of antibiotics, there is an increase in the number of patients infected with Methicillin-resistant Staphylococcus Aureus (MRSA), Extended Spectrum Beta-Lactamases (ESBL) and ESBL selecting for carbapenem-resistance (ESBLCARBA). This study aims to study factors affecting antibiotic resistance management. An additional aim is to use a multidisciplinary approach for a subject that has mostly been studied with quantitative methods. First, linear regressions investigated any possible significant changes of prescription rates in outpatient care, hospital usage of antibiotic groups and antibiotic resistance. After this, nine interviews were conducted with physicians in outpatient care, hospital care and with representatives from the Swedish Strategic Programme for the Rational Use of Antimicrobial Agents and Surveillance of Resistance (Strama), a network working for Swedish prevention against antibiotics resistance. There was a significant decrease in the number of prescriptions of antibiotics in outpatient care among all Swedish counties and a small, but significant increase of antibiotics used in hospitals. The number of patients infected with multidrug resistant bacteria also show a significant increase. The interviews revealed that health care workers in all counties follow the same guidelines and try to be as specific as possible in choosing antibiotics to hit specific bacteria. The respondents suggested migration and extended travelling as explanations to the growing number of cases of multidrug resistant bacteria. Further, two major factors emerged as important for an efficient antibiotic resistance management; Education/knowledge and Discussion. The results indicate a need for further research on rational usage of antibiotics and the use of broad-spectrum antibiotics in hospital care, rather than the reduction through prescriptions. The results indicate that rational usage has a bigger impact than reduction. Using a multidisciplinary approach gave a broader perspective on the issue and future studies should see the possibilities of mixing quantitative and qualitative studies.

  • 161. Bergh, F T
    et al.
    Flinn, Elisabeth M
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Svaren, J
    Wright, Anthony P
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Horz, W
    Comparison of nucleosome remodeling by the yeast transcription factor Pho4 and the glucocorticoid receptor2000In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 275, no 12, p. 9035-9042Article in journal (Refereed)
    Abstract [en]

    Chromatin reorganization of the PHO5 and murine mammary tumor virus (MMTV) promoters is triggered by binding of either Pho4 or the glucocorticoid receptor (GR), respectively. In order to compare the ability of Pho4 and GR to remodel chromatin and activate transcription, hybrid promoter constructs were created by insertion of the MMTV B nucleosome sequence into the PHO5 promoter and then transformed into a yeast strain expressing GR, Activation of either Pho4 (by phosphate depletion) or GR (by hormone addition) resulted in only slight induction of hybrid promoter activity. However, simultaneous activation of both Pho4 and GR resulted in synergistic activation to levels exceeding that of the wild type PHO5 promoter. Under these conditions, Pho4 completely disrupted the nucleosome containing its binding site. In contrast, GR had little effect on the stability of the MMTV B nucleosome. A minimal transactivation domain of the GR fused to the Pho4 DNA-binding domain is capable of efficiently disrupting the nucleosome with a Pho4-binding site, whereas the complementary hybrid protein (Pho4 activation domain, GR DNA-binding domain) does not labilize the B nucleosome. Therefore, we conclude that significant activation by Pho4 requires nucleosome disruption, whereas equivalent transcriptional activation by GR is not accompanied by overt perturbation of nucleosome structure. Our results show that the DNA-binding domains of the two factors play critical roles in determining how chromatin structure is modified during promoter activation.

  • 162.
    Bergman, Daniella
    Södertörn University College, School of Discourse Studies.
    Om arternas överlevnad: en artikelserie om den biologiska mångfalden i Sverige2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Överingress:

    Tänk att du är på en skogspromenad, alla träd har smala

    stammar och är antingen gran eller tall. Kvittret och sången

    har försvunnit eftersom här inte finns några insekter för

    fåglarna att äta. Den biologiska mångfalden i Sverige är

    viktig för att vi ska må bra. I dag bryter många skogsägare

    mot lagen när de avverkar skog och det påverkar den

    biologiska mångfalden negativt.

    När valet nu står mellan gamla träd och nya hus, i ett

    samhälle med bostadsbrist, är prioriteringarna inte självklara.

  • 163.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Engqvist, Robert
    Karolinska Institute.
    Stålhandske, C
    Chemical Centre, Lund.
    Wallberg, H
    KTH.
    Studies of the reactions between indole-2,3-diones (isatins) and 2-aminobenzylamine2003In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 59, no 7, p. 1033-1048Article in journal (Refereed)
  • 164.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Janosik, T
    Koch, E
    Pelcman, B
    Acid-induced dimerization of 3-(1H-indol-3-yl)maleimides. Formation of cyclopentindole derivatives2000In: JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1, ISSN 1470-4358, no 16, p. 2615-2621Article in journal (Refereed)
    Abstract [en]

    Acid-induced dimerizations of 3-substituted maleimides have been investigated, leading to e.g. the cyclopentindole 9 and the deeply coloured spiro compounds 24 and 25 in good yields. 3-(1H-Indol-3-yl)maleimide 6b readily gave the cycloaddition products 13-15 on treatment with appropriate dienophiles. In addition, several related 3,3-di-(1H-indol-3-yl)succinimides have been prepared and studied.

  • 165.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Janosik, T
    Yudina, L
    Desarbre, E
    Lidgren, G
    Venemalm, L
    Reactions of 1,2-bis(1H-indol-2-yl)ethane: Formation of indolo[2,3-c]carbazole and cyclohept[1,2-b : 5,4-b ']bisindole derivatives2000In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 56, no 13, p. 1911-1916Article in journal (Refereed)
    Abstract [en]

    1,2-Bis(1H-indol-2-yl)ethane (9) has been prepared and converted into indolo[2,3-c]carbazole (8) using palladium acetate in refluxing acetic acid. Reaction of 9 with CoF3 in hot TFA led to isolation of cyclohept[1,2-b:5,4-b']bisindole derivatives 11 and 12, which could be elaborated into further derivatives. Treatment of 9 with orthoesters, aldehydes and ketones under acidic conditions afforded additional bisindoles containing a seven-membered ring.

  • 166.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Janosik, Tomasz
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Recent progress in the chemistry of sulfur-containing indoles2002In: Progress in Heterocyclic Chemistry, ISSN 0959-6380, Vol. 14, no C, p. 1-18Article in journal (Refereed)
  • 167.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institutet.
    Janosik, Tomasz
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institutet.
    Wahlström, Niklas
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institutet.
    Indolocarbazoles2001In: Advances in Heterocyclic Chemistry, ISSN 0065-2725, E-ISSN 1557-8429, Vol. 80, p. 1-71Article, review/survey (Refereed)
  • 168.
    Bergman, Jan
    et al.
    Södertörn University, School of Life Sciences.
    Johnson, Ann-Louise
    A short synthesis of the carbazole alkaloid clausine E2006In: Organic preparations and procedures international, ISSN 0030-4948, E-ISSN 1945-5453, Vol. 38, no 6, p. 593-599Article in journal (Refereed)
  • 169.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Koch, E
    Pelcman, B
    Coupling reactions of indole-3-acetic acid derivatives. Synthesis of arcyriaflavin A2000In: JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1, ISSN 1470-4358, no 16, p. 2609-2614Article in journal (Refereed)
    Abstract [en]

    The bisindolesuccinic acid methyl ester 10 was obtained by an iodine-promoted coupling of the dianion 9. The diester was converted to the N-benzylimide 12, which was oxidatively cyclized to the indolo[2,3-a]pyrrolo[3,4-c]carbazole 15. The diester 10 could be directly transformed to the known indolocarbazole diester 27 via acid-induced intramolecular cyclization in TFA. The same methodology gave arcyriaflavin A 4 from the succinimide 18b.

  • 170.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Rehn, S
    Synthesis of 4-oxo-4,5-dihydro-3H-pyrrolo[2,3-c]quinoline-1-carboxylic acid ethyl ester and its isomer 1-oxo-2,9-dihydro-1H-beta-carboline-4-carboxylic acid ethyl ester2002In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 58, no 45, p. 9179-9185Article in journal (Refereed)
    Abstract [en]

    4-Oxo-4,5-dihydro-3H-pyrrolo[2,3-c]quinoline-1-carboxylic acid ethyl ester was obtained when TosMIC was reacted with 3-methylene-oxindole acetic acid ethyl ester. An alternative synthesis to this pyrroloquinolone was performed via a reduction of a 2,3,4-trisubstituted pyrrole obtained in turn by treatment of a vinyl sulfone with ethyl isocyanoacetate under basic conditions. A beta-carboline, isomeric with the pyrroloquinolone, was synthesised utilizing a tosylimine.

  • 171.
    Bergman, Jan
    et al.
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Wahlström, Niklas
    Södertörn University, Avdelning Naturvetenskap. Karolinska Institute.
    Yudina, L N
    Tholander, J
    Lidgren, G
    Synthesis of indolocarbazole quinones; potent aryl hydrocarbon receptor ligands2002In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 58, no 7, p. 1443-1452Article in journal (Refereed)
    Abstract [en]

    Syntheses of indolo[2,3-b]carbazole-6,12-dione and the isomeric indolo[3,2-b]carbazole-6,12-dione, an extremely efficient inducer of the aryl hydrocarbon (Ah) receptor are described. Initial oxidation of the parent indolo[3,2-b]carbazole followed by several different ring-closing strategies produced the latter compound. Entries into syntheses of unsymmetrical 6,12-disubstituted indolo[2,3-b]carbazoles are also described.

  • 172.
    Bergström, Emma
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Media Technology.
    Den mobilanpassade jobbrekryteringsprocessen: En kvalitativ undersökning om två intressentgruppers användarupplevelse av tjänsten Uptrail2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to examine two user groups experience and usage of the mobile job advertising service Uptrail. The two groups that are the focus of this work are the companies that use the service for job recruitment and job-seekers that have applied for work through Uptrail. In which context job-seekers apply for work through the service and why is also examined in this study. This is to give an understanding of how the mobile interface might influence users behaviour during the job recruitment process. The study is based on a qualitative research method where individual in-depth interviews with representatives from the different groups are used for gathering data. Also a shorter observation has been applied during the interviews with the job seekers. Collected data were then analyzed through an inductive interpretation method and combined with previous research and theories regarding mobile usage, context, digital recruitment (e-recruitment) and user experience (UX).

    The result of the study implies that Uptrail has impacted the motives behind job advertising by affecting the user experience of the recruitment process. Job applicants experienced that the mobile format and the process of the service changed their habits on applying for work through digital application. In line with previous research results from this study also suggest that the usage of mobile services largely takes place in “home like” environments. This is explained as a consequence of existing attitudes and thoughts regarding the job search process. 

  • 173.
    Bergström, Sara
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Effektmätning inom eventbranschen: En plan för mätning av effekt och ROI inom eventbranschen2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The competition in the event industry is tough; the event agencies have to work hard to keep customers. Event marketing is partly about changing the receivers’ attitudes about a specific topic. The only way to find out whether attitudes have been changed is to measure the effects of the event.

    This report discusses in what way event agencies evaluate the effect of their events. I came to the conclusion that it is not common for event agencies to measure the effect. The reason is mostly because it is expensive to hire a company that does it, but also because it takes a lot of time. The solution is to define a method for evaluation that is simple, flexible and inexpensive for everyone involved.

    Even though this report is about evaluation in the event industry, I also look at evaluation in the advertising business, to find possible similarities. The outcome is a possible solution used for smartphones. One possible method to use is called Telia Mobil Respons and it is both easy to understand and manage, but also cost effective. 

  • 174.
    Berini, Francesca
    et al.
    Politecnico di Milano and University of Insubria, Varese, Italy.
    Presti, Ilaria
    Politecnico di Milano and University of Insubria, Varese, Italy / Chemo Biosynthesis, Corana, Pavia, Italy.
    Beltrametti, Fabrizio
    Actygea, Gerenzano, Varese, Italy.
    Pedroli, Marco
    Vårum, Kjell M
    Norwegian University of Science and Technology, Trondheim, Norway.
    Pollegioni, Loredano
    Politecnico di Milano and University of Insubria, Varese, Italy.
    Sjöling, Sara
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Marinelli, Flavia
    Politecnico di Milano and University of Insubria, Varese, Italy.
    Production and characterization of a novel antifungal chitinase identified by functional screening of a suppressive-soil metagenome2017In: Microbial Cell Factories, ISSN 1475-2859, E-ISSN 1475-2859, Vol. 16, no 1, article id 16Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Through functional screening of a fosmid library, generated from a phytopathogen-suppressive soil metagenome, the novel antifungal chitinase-named Chi18H8 and belonging to family 18 glycosyl hydrolases-was previously discovered. The initial extremely low yield of Chi18H8 recombinant production and purification from Escherichia coli cells (21 μg/g cell) limited its characterization, thus preventing further investigation on its biotechnological potential.

    RESULTS: We report on how we succeeded in producing hundreds of milligrams of pure and biologically active Chi18H8 by developing and scaling up to a high-yielding, 30 L bioreactor process, based on a novel method of mild solubilization of E. coli inclusion bodies in lactic acid aqueous solution, coupled with a single step purification by hydrophobic interaction chromatography. Chi18H8 was characterized as a Ca(2+)-dependent mesophilic chitobiosidase, active on chitin substrates at acidic pHs and possessing interesting features, such as solvent tolerance, long-term stability in acidic environment and antifungal activity against the phytopathogens Fusarium graminearum and Rhizoctonia solani. Additionally, Chi18H8 was found to operate according to a non-processive endomode of action on a water-soluble chitin-like substrate.

    CONCLUSIONS: Expression screening of a metagenomic library may allow access to the functional diversity of uncultivable microbiota and to the discovery of novel enzymes useful for biotechnological applications. A persisting bottleneck, however, is the lack of methods for large scale production of metagenome-sourced enzymes from genes of unknown origin in the commonly used microbial hosts. To our knowledge, this is the first report on a novel metagenome-sourced enzyme produced in hundreds-of-milligram amount by recovering the protein in the biologically active form from recombinant E. coli inclusion bodies.

  • 175.
    Berkmann, Anna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Greening Potentials and Limits of Eco-Labelling Schemes in the EU: A policy evaluation with a focus on small firms in the German coffee-processing sector2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As SMEs transformation to sustainable practices in manufacturing, processing and services, is declared to be the key to a green growth model, the research in this thesis aims to understand in what way eco-labelling can be a part of that. In order to approach this complex issue, the thesis aims to identify the greening potential and the limits of contemporary eco-labelling schemes for SME product within the German coffee-processing sector. With regard to that, the thesis applied the policy evaluation method "Program Theory Evaluation" (PTE), which assesses a policy in place and thus provides information how the introduction and the function of eco-labelling schemes is observed and perceived by German coffee-processing SMEs (GCPS). Hence, based on a policy evaluation from a rational perspective, which has the focus on the policy’s problem-solving process and implementation cycle, the thesis reveals how eco-labelling schemes’ underlying theoretical greening strategy act in practice to German coffee-processing SME (GCPS). Thereby it could be evaluated that eco-labelling schemes imply shortcomings to address and green GCPS high quality coffee products. As the PTE-method aims also on optimizing the policy’s rationalisation, the inappropriate or failed implementation of eco-labelling schemes by GCPS has been further explored. To grasp the eco-labelling schemes extent of limits to green GCPS products, the thesis compares and analyses the policy evaluation results against the backdrop of eco-labelling schemes’ normative theoretical policy conception and in the light of "Environmental Authority of Political Consumerism (Ecological Modernisation Theory)". With regard to that, the thesis fosters a policy learning process and uncovers that eco-labelling scheme eco-labelling schemes potential to green GCPS products is limited and conditioned to this a lower level of sustainable value as they are focused to supply mainly the demand for mainstream coffee products. Hence, the thesis concludes that it is not the underlying rationality of eco-labelling schemes, namely being a consumer-oriented and market-based policy instrument that does not apply to green GCPS products. However, this opens up a new perspective as it points out a sustainable quality gap between products using eco-labelling schemes and non-labelled GCPS high quality products. In return this raises considerations in terms of improving eco-labelling schemes’ contribution to sustainable development. Thus the thesis argues to optimize their rationalization with regard to GCPS high quality products as frontrunners of tomorrow’s sustainability.

  • 176. Bernard, Pascal
    et al.
    Schmidt, Christine Katrin
    Vaur, Sabine
    Dheur, Sonia
    Drogat, Julie
    Genier, Sylvie
    Ekwall, Karl
    Södertörn University, School of Life Sciences.
    Uhlmann, Frank
    Javerzat, Jean-Paul
    Cell-cycle regulation of cohesin stability along fission yeast chromosomes2008In: EMBO Journal, ISSN 0261-4189, E-ISSN 1460-2075, Vol. 27, no 1, p. 111-121Article in journal (Refereed)
    Abstract [en]

    Sister chromatid cohesion is mediated by cohesin, but the process of cohesion establishment during S-phase is still enigmatic. In mammalian cells, cohesin binding to chromatin is dynamic in G1, but becomes stabilized during S-phase. Whether the regulation of cohesin stability is integral to the process of cohesion establishment is unknown. Here, we provide evidence that fission yeast cohesin also displays dynamic behavior. Cohesin association with G1 chromosomes requires continued activity of the cohesin loader Mis4/Ssl3, suggesting that repeated loading cycles maintain cohesin binding. Cohesin instability in G1 depends on wpl1, the fission yeast ortholog of mammalian Wapl, suggestive of a conserved mechanism that controls cohesin stability on chromosomes. wpl1 is nonessential, indicating that a change in wpl1-dependent cohesin dynamics is dispensable for cohesion establishment. Instead, we find that cohesin stability increases at the time of S-phase in a reaction that can be uncoupled from DNA replication. Hence, cohesin stabilization might be a pre-requisite for cohesion establishment rather than its consequence.

  • 177.
    Berndt, Kurt D
    University of Chicago, USA.
    Design, synthesis, and characterization of amphiphilic helical peptides as models of protein structure1989Doctoral thesis, monograph (Other academic)
  • 178.
    Berndt, Kurt D
    et al.
    Eidgenössische Technische Hochschule-Hönggerberg, Zürich, Switzerland.
    Beunink, J
    Schröder, W
    Wüthrich, K
    Designed replacement of an internal hydration water molecule in BPTI: structural and functional implications of a glycine-to-serine mutation.1993In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 32, p. 4564-4570Article in journal (Refereed)
    Abstract [en]

    The three-dimensional structure of the basic pancreatic trypsin inhibitor (BPTI) contains four internal water molecules, which form a total of nine intermolecular hydrogen bonds with the BPTI polypeptide chain. To investigate the effect of such internal hydration on protein structure and stability, we displaced one of the internal water molecules in a recombinant BPTI analogue, BPTI(G36S), in which Gly 36 is replaced by serine. The replacement of a water molecule by the seryl side chain was established by the absence of the protein-water nuclear Overhauser effects (NOE) that had been attributed to the water molecule near Gly 36 in wild-type BPTI and by the presence of new, intramolecular NOEs to the hydroxyl proton of Ser 36. BPTI(G36S) has slightly reduced thermal stability compared to BPTI, corresponding to a destabilization by delta (delta G) approximately 0.7 kcal/M in 6 M guanidinium hydrochloride solution. Additionally, the stabilities of the complexes formed between BPTI(G36S) and trypsin, plasmin, or kallikrein are significantly reduced when compared to the corresponding complexes with wild-type BPTI.

  • 179.
    Berndt, Kurt D
    et al.
    Eidgenossische TH-Honggerberg, Zürich, Switzerland.
    Güntert, P
    Wüthrich, K
    Nuclear-Magnetic-Resonance Solution Structure of Dendrotoxin-K from the Venom of Dendroaspis-Polylepis-Polylepis1993In: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 234, no 3, p. 735-750Article in journal (Refereed)
  • 180.
    Berndt, Kurt D
    et al.
    Eidgenösische Technische Hochschule-Hönggerberg, Zürich, Switzerland.
    Güntert, Peter
    Orbons, Leonard P.M.
    Wüthrich, Kurt
    Determination of a high-quality nuclear magnetic resonance solution structure of the bovine pancreatic trypsin inhibitor and comparison with three crystal structures1992In: Journal of Molecular Biology, Vol. 227, p. 757-775Article in journal (Refereed)
    Abstract [en]

    A high-quality three-dimensional structure of the bovine pancreatic trypsin inhibitor (BPTI) in aqueous solution was determined by 1H nuclear magnetic resonance (n.m.r.) spectroscopy and compared to the three available high-resolution X-ray crystal structures. A newly collected input of 642 distance constraints derived from nuclear Overhauser effects and 115 dihedral angle constraints was used for the structure calculations with the program DIANA, followed by restrained energy minimization with the program AMBER. The BPTI solution structure is represented by a group of 20 conformers with an average root-mean-square deviation (RMSD) relative to the mean solution structure of 0.43 A for backbone atoms and 0.92 A for all heavy atoms of residues 2 to 56. The pairwise RMSD values of the three crystal structures relative to the mean solution structure are 0.76 to 0.85 A for the backbone atoms and 1.24 to 1.33 A for all heavy atoms of residues 2 to 56. Small local differences in backbone atom positions between the solution structure and the X-ray structures near residues 9, 25 to 27, 46 to 48 and 52 to 58, and conformational differences for individual amino acid side-chains were analyzed for possible correlations with intermolecular protein-protein contacts in the crystal lattices, using the pairwise RMSD values among the three crystal structures as a reference.

  • 181.
    Berndt, Kurt D
    et al.
    Eidgenössische TH-Hönggerberg, Zürich, Switzerland.
    Güntert, Peter
    Wüthrich, Kurt
    Conformational sampling by NMR solution structures calculated with the program DIANA evaluated by comparison with long-time molecular dynamics calculations in explicit water1996In: Proteins: Structure, Function, and Bioinformatics, ISSN 0887-3585, E-ISSN 1097-0134, Vol. 24, p. 304-313Article in journal (Refereed)
    Abstract [en]

    The NMR solution structure of bovine pancreatic trypsin inhibitor (BPTI) obtained by distance geometry calculations with the program DIANA is compared with groups of conformers generated by molecular dynamics (MD) simulations in explicit water at ambient temperature and pressure. The MD simulations started from a single conformer and were free or restrained either by the experimental NOE distance restraints or by time-averaged restraints; the groups of conformers were collected either in 10 ps intervals during 200 ps periods of simulation, or in 50 ps intervals during a 1 ns period of simulation. Overall, these comparisons show that the standard protein structure determination protocol with the program DIANA provides a picture of the protein structure that is in agreement with MD simulations using "realistic" potential functions over a nanosecond timescale. For well-constrained molecular regions there is a trend in the free MD simulation of duration 1 ns that the sampling of the conformation space is slightly increased relative to the DIANA calculations. In contrast, for surface-exposed side-chains that are less extensively constrained by the NMR data, the DIANA conformers tend to sample larger regions of conformational space than conformers selected from any of the MD trajectories. Additional insights into the behavior of surface side-chains come from comparison of the MD runs of 200 ps or 1 ns duration. In this time range the sampling of conformation space by the protein surface depends strongly on the length of the simulation, which indicates that significant side-chain transitions occur on the nanosecond timescale and that much longer simulations will be needed to obtain statistically significant data on side-chain dynamics.

  • 182. Berndtsson, Johan
    et al.
    Normark, Maria
    The coordinative functions of flight strips: air traffic control revisited1999In: Proceedings of the international ACM SIGGROUP conference on Supporting group work, GROUP '99 / [ed] Stephen C Hayne, New York: ACM , 1999, p. 101-110Conference paper (Refereed)
    Abstract [en]

    Cooperation in time-critical and physically distributed worksettings, such as air traffic control, requires extensive coordinationbetween the involved actors. For this coordination to beefficient the controllers rely both on the comprehensive use ofrules and procedures, and on artifacts supporting them infollowing these procedures. At the Copenhagen Air TrafficControl Center this coordination is largely carried out throughthe use of a flight plan database system, paper flight strips, anda closed-circuit television system. In relation to the introductionof a new and increasingly automated system in the year 2003 this paper discusses the coordinative functions served bythese three, soon to be replaced, artifacts from a design perspective.Despite the skepticism expressed in previous research,our results show that a further computerization couldbe successful if the coordinative functions the system currentlyfulfills are properly preserved.

  • 183.
    Berntsson, Jenny
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Regional destinationsutveckling: Visit Roslagen, ett samarbete i tiden?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A large proportion of Sweden's tax estimated revenue generated by the tourism industry. Sweden is due to this nutritional sharp increase created a national strategy for both government and business. One of the key words in this strategy is on sustainable destination development, which will increase more of the country's destinations' competitiveness in a sustainable way in order to create a stronger competitiveness in Sweden and internationally. Roslagen is a region that consists of four municipalities, three of these municipalities have formed a company called Destination Visit Roslagen AB. This study focuses on the planning regarding the hospitality industry seen over time in the region Roslagen. It also illustrates how this design looks today regarding cooperation and communication between the public and the private business. The study also describes how the planning around Roslagens tourism industry is controlled today by the company through agreements with municipalities, and how far this development is considered to be the best solution for the region. Finally also examines sustainability aspects of the destination developed and controlled.

    This study used a qualitative approach and a hermeneutic approach. To examine the planning of Roslagens tourism used primary and secondary data. The primary data consists of interviews with Norrtälje and Östhammar business leaders who for a long time and still work with the tourism industry development, and is with and ensures that the company Visit Roslagen care what the contract states. To get a broader picture of Roslagens planning also Visit Roslagens CEO interviewed. The secondary data consists, among other things, in a previous interview survey by Visit Roslagens project manager and some newspaper articles and a description of the agreements between the Company and the municipalities.

    To form an understanding of the topic destination development has previous research and literature used on destination development, planning and management, internal and external communications as well as identity and image, finally, in theory, paragraph describes the effects and sustainable development of the tourism industry.

    The findings in this study show that Roslagen over time have received a stakare merger between the public and private initiatives of public affairs who first were those who stood for the planning of destination development in the region. The national strategy was significant in this development, and created the motivation to form a company for this type of development. The Company has an agreement with each municipality. Local government agreements are similar and means that the company will manage; -turistutveckling, -turistservice, -Marketing and sales. The influence of the municipality of the company is through the agreements which are then followed up by the two local business managers. In addition to the agreement the company manages all planning on the tourism industry itself. Local authorities believe that this incorporation of the tourism industry planning is good for it to be more long-term when not various policy changes could affect various development decisions in the region, but that it instead is a lngsiktig planning under the agreements should be made in consultation between the tourism industry and the public through Agreements between local authorities and the company. Finally, Roslagens planning on destination development considered sustainable when there is a planning and an increasing interaction between public and private actors on the destination. With this planning increases the likelihood that social and environmental sustainability are protected when these factors are the hospitality industry makes money.

  • 184.
    Bertrand, Yann
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France / Göteborgs universitet.
    Contrasting the general with the particular in phylogenetics - a proposal to keep the meanings of mono/paraphyletic and clade/grade separated2008In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175, Vol. 57, no 3, p. 705-708Article in journal (Refereed)
    Abstract [en]

    Clade and monophyletic group on one hand and grade and paraphyletic group on the other hand are commonly used as pairs of interchangeable terms. I question this apparent synonymy and propose that "monophyly" and "paraphyly" should refer to a property of a set, whereas "clade" and "grade" should apply to individuals resulting from evolutionary process.

  • 185.
    Bertrand, Yann
    Södertörn University, School of Life Sciences. Göteborgs universitet.
    Relationships between nomenclature, phylogenetics and systematics2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Systematists have become increasingly aware of the limits imposed by the current system of nomenclature for accurately representing evolutionary relationships and managing efficiently names associated with clades. In reaction, a new system of nomenclature, the PhyloCode is being developed that fully recognizes the historical nature of taxonomy and the importance of the cladistics revolution. As a consequence, questions emerge about the new historical entities of systematics, questions that can be apprehended through the lens of epistemology, philosophy of language and metaphysics. What is the ontological nature of entities that lack any other essential features besides spatiotemporal properties? How to depart from the fixed realm of immutable and transcendental essence into a worldview wherein all biological entities are characterized by their temporality and materiality? What are the consequences of nomenclatural decisions on other sectors of biology? With the ever growing sequencing capacity and tree reconstructing abilities, our conceptualization of phylogenetic relationships is changing at an unprecedented pace. Then it begs the question, what prevents communication break down when the references of clades’ names are changing almost on a daily basis. These are some of the fundamental issues I am tackling in the present work. Addressing the ontological issue, I argue that species and clades are best perceived as mereological sums of individuals, which means that each biological individual is the unique individual composed of all its less inclusive individuals and nothing more. I propose to separate the meanings of “clade” and “monophyletic group”. I suggest to use “monophyletic” for an epithet referring to a defining property of a set (a natural kind) and “clade” for a noun which corresponds to a historical entity (an individual) resulting from evolutionary process. I present the idea that a phyloname is not attached to a single clade but to a natural kind containing as members the clades that would be selected in counterfactual phylogenies. The defining properties of this natural kind are provided by the phylogenetic definition. Finally I stress that taxonomists are also driven by the will to narrate the same sort of history, when they adjust the reference of names in light of new phylogenetic data, which leads me to submit that taxa can also be perceived as narratives.

  • 186.
    Bertrand, Yann
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France / Göteborgs universitet.
    Species individuality and integrationManuscript (preprint) (Other academic)
  • 187.
    Bertrand, Yann
    et al.
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France / Göteborgs universitet.
    Härlin, Mikael
    Södertörn University, School of Life Sciences.
    Historicism and essentialism in phylogenetic biologyManuscript (preprint) (Other academic)
  • 188.
    Bertrand, Yann
    et al.
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France / Göteborgs universitet.
    Härlin, Mikael
    Södertörn University, School of Life Sciences.
    Phylogenetic hypotheses, taxonomic sameness and the reference of taxon names2008In: Zoologica Scripta, ISSN 0300-3256, E-ISSN 1463-6409, Vol. 37, no 3, p. 337-347Article in journal (Refereed)
    Abstract [en]

    When scientists use a taxon name like Mammalia, it is important that they talk about the same thing. But, what does it mean to be the same thing in different phylogenetic hypotheses? And, how is taxonomic reference maintained across hypotheses? Here, we discuss the differences between real and hypothetical clades, and how such a distinction relates to the sameness problem. Since hypotheses influence how we perceive things and pursue science, we find it important to have a functioning nomenclatural system for clades as perceived in phylogenetic hypotheses. As a solution to the sameness problem for such clades, we argue that a taxon name does not primarily refer to a single clade that somehow mirror the reality of branches in the tree of life. Instead we suggest that a taxon name refers to a set, or natural kind, of counterfactual and reconstructed clades.

  • 189.
    Bertrand, Yann
    et al.
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France.
    Härlin, Mikael
    Södertörn University, School of Life Sciences.
    Stability and universality in the application of taxon names in phylogenetic nomenclature2006In: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 55, no 5, p. 848-858Article in journal (Refereed)
  • 190.
    Bertrand, Yann J.
    et al.
    Science and Historical Investigations of Evolution Laboratory of Dubá, Dubá, Czech Republic.
    Johansson, Magnus
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology. Örebro University.
    Norberg, Peter
    Sahlgrenska University.
    Revisiting Recombination Signal in the Tick-Borne Encephalitis Virus: A Simulation Approach2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 10, article id e0164435Article in journal (Refereed)
    Abstract [en]

    The hypothesis of wide spread reticulate evolution in Tick-Borne Encephalitis virus (TBEV) has recently gained momentum with several publications describing past recombination events involving various TBEV clades. Despite a large body of work, no consensus has yet emerged on TBEV evolutionary dynamics. Understanding the occurrence and frequency of recombination in TBEV bears significant impact on epidemiology, evolution, and vaccination with live vaccines. In this study, we investigated the possibility of detecting recombination events in TBEV by simulating recombinations at several locations on the virus' phylogenetic tree and for different lengths of recombining fragments. We derived estimations of rates of true and false positive for the detection of past recombination events for seven recombination detection algorithms. Our analytical framework can be applied to any investigation dealing with the difficult task of distinguishing genuine recombination signal from background noise. Our results suggest that the problem of false positives associated with low detection P-values in TBEV, is more insidious than generally acknowledged. We reappraised the recombination signals present in the empirical data, and showed that reliable signals could only be obtained in a few cases when highly genetically divergent strains were involved, whereas false positives were common among genetically similar strains. We thus conclude that recombination among wild-type TBEV strains may occur, which has potential implications for vaccination with live vaccines, but that these events are surprisingly rare.

  • 191.
    Bertrand, Yann
    et al.
    Södertörn University, School of Life Sciences. Muséum National d'Histoire Naturelle, Paris, France.
    Pteijel, F.
    Göteborgs universitet.
    Rouse, G. W.
    Adelaide University, Australia.
    Taxonomic surrogacy in biodiversity assessments, and the meaning of Linnaean ranks2006In: Systematics and Biodiversity, ISSN 1477-2000, E-ISSN 1478-0933, Vol. 4, no 2, p. 149-159Article in journal (Refereed)
    Abstract [en]

    The majority of biodiversity assessments use species as the base unit. Recently, a series of studies have suggested replacing numbers of species with higher ranked taxa (genera, families, etc.); a method known as taxonomic surrogacy that has an important potential to save time and resources in assesments of biological diversity. We examine the relationships between taxa and ranks, and suggest that species/higher taxon exchanges are founded on misconceptions about the properties of Linnaean classification. Rank allocations in current classifications constitute a heterogeneous mixture of various historical and contemporary views. Even if all taxa were monophyletic, those referred to the same rank would simply denote separate clades without further equivalence. We conclude that they are no more comparable than any other, non-nested taxa, such as, for example, the genus Rattus and the phylum Arthropoda, and that taxonomic surrogacy tacks justification. These problems are also illustrated with data of polychaetous annelid worms from a broad-scale study of benthic biodiversity and species distributions in the Irish Sea. A recent consensus phylogeny for polychaetes is used to provide three different family-level classifications of polychaetes. We use families as a surrogate for species, and present Shannon-Wiener diversity indices for the different sites and the three different classifications, showing how the diversity measures rely on subjective rank allocations.

  • 192.
    Bertrand, Yann
    et al.
    Göteborg University.
    Töpel, Mats
    Göteborg University.
    Elväng, Annelie
    Södertörn University, School of Life Sciences, Molecular biology.
    Melik, Wessam
    Södertörn University, School of Life Sciences, Chemistry. Södertörn University, School of Life Sciences, Molecular biology.
    Johansson, Magnus
    Södertörn University, School of Life Sciences, Chemistry. Södertörn University, School of Life Sciences, International health.
    First Dating of a Recombination Event in Mammalian Tick-Borne Flaviviruses2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 2, p. e31981-Article in journal (Refereed)
    Abstract [en]

    The mammalian tick-borne flavivirus group (MTBFG) contains viruses associated with important human and animal diseases such as encephalitis and hemorrhagic fever. In contrast to mosquito-borne flaviviruses where recombination events are frequent, the evolutionary dynamic within the MTBFG was believed to be essentially clonal. This assumption was challenged with the recent report of several homologous recombinations within the Tick-borne encephalitis virus (TBEV). We performed a thorough analysis of publicly available genomes in this group and found no compelling evidence for the previously identified recombinations. However, our results show for the first time that demonstrable recombination (i.e., with large statistical support and strong phylogenetic evidences) has occurred in the MTBFG, more specifically within the Louping ill virus lineage. Putative parents, recombinant strains and breakpoints were further tested for statistical significance using phylogenetic methods. We investigated the time of divergence between the recombinant and parental strains in a Bayesian framework. The recombination was estimated to have occurred during a window of 282 to 76 years before the present. By unravelling the temporal setting of the event, we adduce hypotheses about the ecological conditions that could account for the observed recombination.

  • 193.
    Besara, Sheyno
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Barbäck, Zanna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Spelroll "At Heart": Spelrollers inverkan på erfarna spelares problemlösningsförmåga i vardagen2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Games offer a safe and motivational environment that allows and encourages trial and error. A gamer can act in the game without any real consequences in real life. Thereby a gamer is offered the opportunity to develop a broad set of skills. Games have earlier been proven to develop gamer’s problem-solving skills. Roles, as an important part of a game’s structure, contribute to a deepened and more certain development of a diversity of skills – problem solving as one of them. In this paper we examine the relation between roles and gamer’s development of their problem-solving skills in real life – whether it exits and if so, to what extent.

    We’ve found that roles encourage a creative form of problem solving and that gamers develop their problem-solving skills in real life differently depending on which role they play as. Each role posses a unique set of skills, thereby their performance differs depending on the situation. Gamers develop their problem- solving skills to different extents since the roles require different actions to solve problems in the game. 

  • 194.
    Besara, Sheyno
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Barbäck, Zanna
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Webbshop för optik: En förstudie: Vikten av användbarhet och aktuella trender inom e-handel2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Trends are part of shaping the market standards and keep challenging the competition to stay on their toes. E-commerce is a fast growing field, a lot due to the rapid evolution of technology. As a result, new trends emerge and form the market once again. Followed by new trends are new possibilities and measures, which lead to higher demands and expectations from the consumers. To manage an e-business successfully it is a prerequisite to stay updated with the current e-commerce trends to be able to keep up with the competitors. To be able to embrace trends and keep up with the competition, a great mean is usability. It is vital to any kind of service to have a good usability, and to maintain it regularly, for it’s chances of survival in the harsh competition. For returning consumers it is important to listen to their expectations, and see to it that the service meet their needs with user-friendly functions. Since the experience of the service is what stays with them. Usability is the backbone of the service, ensuring the user journey to be as smooth as possible, and enhance both the service itself and the consumers’ experience. So it is not sufficient enough to only implement current trends into the service. Without good usability to complement with – neither the trends nor the service will reach their full potential.

    This paper is a pre-study and a result of a degree project, and covers general guidelines for the development of a web shop for optics. The guidelines are based on research on usability and current e-commerce trends. To produce these guidelines, methods such as Brand Experience Workshop, Creative Session and interviews with the target group have been executed.

  • 195. Beskow, Anne
    et al.
    Wright, Anthony P. H.
    Södertörn University, School of Life Sciences.
    Comparative analysis of regulatory transcription factors in Schizosaccharomyces pombe and budding yeasts2006In: Yeast, ISSN 0749-503X, E-ISSN 1097-0061, Vol. 23, no 13, p. 929-935Article in journal (Refereed)
    Abstract [en]

    Regulatory transcription factors (rTFs), which bind specific DNA sequences in the regulatory regions of genes and subsequently activate or repress transcription, play a central role in programming genomic expression. The number of rTFs in a species might therefore reflect its functional complexity. For simple organisms like yeast, a relatively small number of rTFs might be expected that is fairly constant between yeast species. We show that the budding yeast, Saccharomyces cerevisiae, contains 201 rTfs, which is one of the largest rTF numbers found in yeast species for which genome sequences are available. This is a much higher number than the 129 rTFs found in the fission yeast, Schizosaccharomyces pombe, which is currently the yeast with the lowest number of rTFs. Comparative analysis of several different budding yeast species shows that most of the 'extra' rTFs found in S. cerevisiae were probably acquired as a result of a whole genome duplication (WGD) event that occurred in an ancestor of a subset of budding yeast species. However, we also show that budding yeast species that have not been affected by the WGD contain a greater number of rTFs than S. pombe (mean = 145). Thus, two or more mechanisms have led to the 60% increase in rTFs in S. cerevisiae compared to S. pombe. This difference may correlate with a more extensive functional divergence in budding yeasts compared to fission yeasts. The relatively small number of rTFs in S. pombe make this organism an attractive model for global studies of mechanisms that programme gene expression.

  • 196.
    Betzeki, Christina
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Media Technology.
    Swedan, Leyla
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Media Technology.
    Persuasive design som medel för miljövänligt agerande: En studie om hur funktioner i miljöfrämjande mobilapplikationer kan motivera användare att agera miljövänligt2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to investigate how an environmental mobile application can motivate users to act more eco-friendly by using persuasive design principles. In this study, we identify a set of key principles to consider when designing mobile persuasive technology in order to motivate and influence pro-environmental behavior change. We evaluated three existing mobile applications by using PSD design principles. After the evaluation, one mobile application was selected for usertesting, with a total of six participants. The participants received one week to get familiar with the application and its functionalities . Furthermore, the participants received a survey with general questions about their eco-friendly habits. The upcoming phase included the interview we conducted, which contained questions to bring forward the participants opinions about functions and motivation factors that could affect their usage of eco-friendly applications. The result showed that the design principles rewards, personalization, simulation, self-monitoring, normative influence, cooperation, social comparison, competition and reminders had the greatest influence on the users motivation to use the application and act eco-friendly. The reason of importance for the chosen design principles was mainly due to individual, social and practical factors.

  • 197.
    Betzholtz, Per-Eric
    et al.
    University of Kalmar.
    Ehrig, A
    Lindeborg, M
    Dinnétz, Patrik
    University of Kalmar.
    Food plant density, patch isolation and vegetation height determine occurrence in a Swedish metapopulation of the marsh fritillary Euphydryas aurinia (Rottemburg, 1775) (Lepidoptera, Nymphalidae)2007In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 11, no 4, p. 343-350Article in journal (Refereed)
    Abstract [en]

    The occurrence pattern of the marsh fritillary was studied within a patch network on the Baltic island Oland, Sweden. Presence/absence was established for potentially suitable habitat patches (n = 158) on calcareous moist grassland and analyzed in a multiple logistic regression model where patch area, patch isolation and nine habitat quality variables were included as explanatory variables. Larval food plant density was positively, and patch isolation negatively, correlated to the presence of Euphydryas aurinia. Area did not contribute to the explanation of the occurrence pattern. Significant interactions between larval food plant density times patch isolation, and larval food plant density times vegetation height, show that with low food plant density the butterfly primarily occurs in patches with a vegetation height of 4-10 cm, within a distance of 250 m from nearest occupied patch. In patches with a high food plant density the butterfly occurs in patches where the vegetation height is higher, 4-16 cm, and the distance to nearest occupied patch can be longer, up to 1.4 km. This study supports earlier findings in other regions, suggesting that a network of adjacent patches with a high food plant density and a vegetation height within the preferred threshold, despite their size, is an apparent conservation goal.

  • 198. Bianchi, Thomas S
    et al.
    Engelhaupt, Erika
    Westman, Per
    Andrén, Thomas
    Rolff, Carl
    Elmgren, Ragnar
    Cyanobacterial blooms in the Baltic Sea: Natural or human-induced?2000In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 45, no 3, p. 716-726Article in journal (Refereed)
    Abstract [en]

    Massive summer blooms of nitrogen-fixing cyanobacteria have been documented in the Baltic Sea since the 19th century, but are reported to have increased in frequency, biomass, and duration in recent decades-presumably in response to the well-documented anthropogenic eutrophication of the Baltic. Here, we present an 8,000-yr record of fossil cyanobacterial pigments, diatom microfossil assemblages, and delta(15)N variations in sediment cores from the Baltic proper. This record indicates that nitrogen-living cyanobacterial blooms are nearly as old as the present brackish water phase of the Baltic Sea, starting as far back as ca. 7000 B.P.-soon after the former freshwater Ancylus Lake turned into the brackish Litorina Sea. Demonstration of cyanobacterial blooms in the Baltic prior to the greatly increased anthropogenic nutrient inputs of the 20th century is important for setting realistic goals when trying to reduce the magnitude of present brooms. Our results suggest that the presently predominating nitrogen (N) limitation of phytoplankton in the Baltic Sea proper is not man-induced, but a natural phenomenon, which has endured for some 7,000 yr. These cyanobacterial blooms were possibly initiated by increased availability of phosphorus (P)-from inflow of P-rich seawater and increased P release from sediments-during periods of deep-water anoxia, caused by the establishment of salinity stratification. Efforts to restore the Baltic proper to a more oligotrophic and natural condition should take into account that nitrogen-fixing cyanobacterial blooms are a characteristic, natural feature of this sea.

  • 199.
    Bidla, Gawa
    et al.
    Stockolms universitet.
    Lindgren, Malin
    Södertörn University, School of Life Sciences.
    Theopold, Ulrich
    Stockholms universitet.
    Dushay, Mitchell S.
    Södertörn University, School of Life Sciences.
    Hemolymph coagulation and phenoloxidase in Drosophila larvae2005In: Developmental and Comparative Immunology, ISSN 0145-305X, E-ISSN 1879-0089, Vol. 29, no 8, p. 669-679Article in journal (Refereed)
    Abstract [en]

    Hemolymph coagulation is a first response to wounding in insects. Although studies have been performed in large-bodied insects such as the moth Galleria mellonella, less is known about clotting in Drosophila melanogaster, the insect most useful for genetic and molecular analyses of innate immunity. Here we show the similarities between clots in Drosophila and Galleria by light- and electron microscopy. Phenoloxidase changes the Drosophila clot's physical properties through cross-linking and melanization, but it is not necessary for preliminary soft clot formation. Bacteria associate with the clot, but this alone does not necessarily kill them. The stage is now set for rapid advances in our understanding of insect hemolymph coagulation, its roles in immune defense and wound healing, and for a more comprehensive grasp of the insect immune system in general.

  • 200. Bindler, Richard
    et al.
    Renberg, Ingemar
    Rydberg, Johan
    Andrén, Thomas
    Södertörn University, School of Life Sciences, Geography. Södertörn University, School of Life Sciences, Environmental science.
    Widespread waterborne pollution in central Swedish lakes and the Baltic Sea from pre-industrial mining and metallurgy2009In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 157, p. 2132-2141Article in journal (Refereed)
    Abstract [en]

    Metal pollution is viewed as a modern problem that began in the 19th century and accelerated through the 20th century; however, in many parts of the globe this view is wrong. Here, we studied past waterborne metal pollution in lake sediments from the Bergslagen region in central Sweden, one of many historically important mining regions in Europe. With a focus on lead (including isotopes), we trace mining impacts from a local scale, through a 120-km-long river system draining into Malaren - Sweden’s third largest lake, and finally also the Baltic Sea. Comparison of sediment and peat records shows that pollution from Swedish mining was largely waterborne and that atmospheric deposition was dominated by long-range transport from other regions. Swedish ore lead is detectable from the 10th century, but the greatest impact occurred during the 16th-18th centuries with improvements occurring over recent centuries, i.e., historical pollution > modern industrial pollution.

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