The HIV-1 transactivator of transcription (Tat) is a protein essential for both viral gene expression and virus replication. Tat is an RNA-binding protein that, in cooperation with host cell factors cyclin T1 and cyclin-dependent kinase 9, regulates transcription at the level of elongation. Tat also interacts with numerous other intracellular and extracellular proteins, and is implicated in a number of pathogenic processes. The Tat protein is encoded by two exons and is 101 residues in length. The first exon encodes a 72-residue molecule that activates transcription with the same proficiency as the full-length protein. The physico-chemical properties of Tat make it a particularly challenging target for structural studies: Tat contains seven cysteine residues, six of which are essential for transactivation, and is highly susceptible to oxidative cross-linking and aggregation. In addition, a basic segment (residues 48-57) gives the protein a high net positive charge of +12 at pH 7, endowing it with a high affinity for anionic polymers and surfaces. In order to study the structure of Tat, both alone and in complex with partner molecules, we have developed a system for the bacterial expression and purification of polyhistidine-tagged and isotopically enriched (in 15N and 15N /13C) recombinant HIV-1 Tat1-72 (BH10 isolate) that yields large amounts of protein. These preparations have facilitated the assignment of 95% of the non-proline backbone resonances using heteronuclear 3-dimensional nuclear magnetic resonance (NMR) spectroscopy. Analysis by mass spectrometry and NMR demonstrate that the cysteine-rich Tat protein is unambiguously reduced and monomeric in aqueous solution at pH 4. NMR chemical shifts and coupling constants suggest that it exists in a disordered conformation. Line broadening and multiple peaks in the cysteine-rich and core regions suggest that transient folding occurs in two of the five sequence domains. NMR relaxation parameters were measured and analysed by spectral density and model-free approaches both confirming the lack of structure throughout the length of the molecule. The absence of a fixed conformation and the observation of fast dynamics are consistent with the ability of the Tat protein to interact with a wide variety of proteins and nucleic acid lending further support to the concept that Tat exists as an intrinsically disordered protein.

Arbetstillfredsställelse har många varierande definitioner. Gemensamt är att det handlar om hur tillfreds individen är med sitt arbete. Syftet med studien var att jämföra vård- och bankanställda för att se hur de skiljer sig åt i upplevelsen av inre, yttre och generell arbetstillfredsställelse, var skillnaden ligger och hur viktig arbetsmotivationen är för arbetstillfredsställelse. Sju frågeställningar ligger till grund för studien och 120 bankanställda samt 83 vårdanställda deltog. En enkät på 34 frågor besvarades av samtliga deltagare och analyserades statistiskt. Resultaten visar att bankanställda har generellt högre arbetstillfredsställelse än de vårdanställda. Den faktor där vårdanställda upplever högre grad av generell arbetstillfredsställelse handlar om möjligheten att göra något för någon annan. Det kan bero på att vårdanställda har motivationen att hjälpa andra människor som drivkraft i sitt arbete. Gemensamt för båda branscherna är att arbetstillfredsställelsen ökar med åldern. Förklaring till det kan vara ökad arbetserfarenhet och säkerhet för att känna tillfredsställelse på arbetet.

The HIV-1 transactivator of transcription (Tat) is a protein essential for both viral gene expression and virus replication. Tat is an RNA-binding protein that, in cooperation with host cell factors cyclin T1 and cyclin-dependent kinase 9, regulates transcription at the level of elongation. Tat also interacts with numerous other intracellular and extracellular proteins, and is implicated in a number of pathogenic processes. The Tat protein is encoded by two exons and is 101 residues in length. The first exon encodes a 72-residue molecule that activates transcription with the same proficiency as the full-length protein. The physico-chemical properties of Tat make it a particularly challenging target for structural studies: Tat contains seven cysteine residues, six of which are essential for transactivation, and is highly susceptible to oxidative cross-linking and aggregation. In addition, a basic segment (residues 48-57) gives the protein a high net positive charge of +12 at pH 7, endowing it with a high affinity for anionic polymers and surfaces. In order to study the structure of Tat, both alone and in complex with partner molecules, we have developed a system for the bacterial expression and purification of polyhistidine-tagged and isotopically enriched (in 15N and 15N /13C) recombinant HIV-1 Tat1-72 (BH10 isolate) that yields large amounts of protein. These preparations have facilitated the assignment of 95% of the non-proline backbone resonances using heteronuclear 3-dimensional nuclear magnetic resonance (NMR) spectroscopy. Analysis by mass spectrometry and NMR demonstrate that the cysteine-rich Tat protein is unambiguously reduced and monomeric in aqueous solution at pH 4. NMR chemical shifts and coupling constants suggest that it exists in a disordered conformation. Line broadening and multiple peaks in the cysteine-rich and core regions suggest that transient folding occurs in two of the five sequence domains. NMR relaxation parameters were measured and analysed by spectral density and model-free approaches both confirming the lack of structure throughout the length of the molecule. The absence of a fixed conformation and the observation of fast dynamics are consistent with the ability of the Tat protein to interact with a wide variety of proteins and nucleic acid lending further support to the concept that Tat exists as an intrinsically disordered protein.

Human APOBEC3 proteins are host-encoded intrinsic restriction factors that can prevent the replication of a broad range of human and animal retroviruses such as HIV, SIV, FIV, MLVs and XMRV. The main pathway of the restriction is believed to occur as a result of the cytidine deaminase activity of these proteins that converts cytidines into uridines in single-stranded DNA retroviral replication intermediates. Uridines in these DNA intermediates disrupt the viral replication cycle and also alter retrovirus infectivity because of the C-to-T transition mutations generated as a result of the deaminase activity on the minus strand DNA. In addition, human APOBEC3 proteins also exhibit a deamination-independent pathway to restrict retroviruses that is not currently well understood. Although the restriction of retroviruses by human APOBEC3 proteins has been intensely studied in vitro, our understanding of how the murine APOBEC3 (mA3) protein restricts retroviruses and/or prevents zoonotic infections in vivo is very limited. In contrast to humans and primates that have 7 APOBEC3 genes, mice have but a single copy. My study of the function and structure of mA3 revealed that it has an inverted functional organization for cytidine deamination in comparison to the human A3G catalytic sites. I have also found that disruption of the integrity of either of these catalytic sites substantially impedes restriction of HIV and MLV. Interestingly, our data shows that mA3 induces a significant decrease in retroviral activity of HIV and MLVs by exploiting both deamination-dependent and -independent pathways. However, the deaminase activity of mA3 is essential to confer long-term restriction of retroviral infection. My observations suggest that mA3 has dual activities, both deamination-dependent and -independent, that work cooperatively to restrict a broad range of human and animal retroviral pathogens. In the context of the intrinsic immune system, APOBEC3 proteins provide a powerful block to the transmission of retroviral pathogens that very few have found ways to evade.

Individer som utövar någon typ av sport utsätter sig för både psykiskt och fysisk påfrestning. Denna påfrestning kan vara något som stressar individen och måste därför hanteras och bemästras på något sätt.  Syftet med studien var att undersöka vad som motiverar hobby- respektive professionella ryttare, finns det någon skillnad i upplevelsen av motgångar i sin sport mellan hobbyryttare och professionella tävlingsryttare, och om grupperna har olika sätt att bemästra motgångar. Deltagarna var 11 kvinnor, fem professionella ryttare och sex hobbyryttare. Analysen gjordes genom meningskoncentrering, där olika teman utformades efter studiens frågeställningar. Resultatet visade bland annat på att hobbyryttarna använde sig utav undvikande bemästrande strategi i större utsträckning än vad de professionella ryttarna gjorde. Detta skulle kunna bero på att professionella ryttare använde sig mer utav problemfokuserad bemästrandestrategier därför att de hade mer rutin och kunskap inom sporten än hobbyryttarna hade.

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

The research aimed to develop chemically modified PIM-1s for use in adsorption and gas separation processes. In particular, the nitrile group in PIM-1 was converted to several different functional groups to manipulate the interaction ability of PIM-1 with different species. Synthesis of PIM-1 was achieved by two different methods, using both the low (72h, 65 °C) and the high temperature (40 min, 160 °C) methods. Hydrolysis of PIM-1 was performed in the presence of 20% and 10% NaOH solutions (1:1 H2O/ethanol) at 120 and 100 °C, respectively. The reaction resulted in a mixture of hydrolysis products. The composition of the polymer has a profound effect on the final performance of the polymer. Powder samples of hydrolysed PIMs were used in the research. The reduction of nitrile to primary amine was achieved using borane dimethyl sulphide complex, resulting in amine PIM-1. Both membrane and powder forms of amine PIMs were studied. The reaction of PIM-1 with ethanolamine and diethanolamine produced hydroxyalkylaminoalkylamide PIMs. The combination of all available techniques (ATR-IR, solution and solid state NMR, TGA, Elemental analysis, UV, GPC, MALDI-ToF, low pressure N2 sorption) was used to characterise the polymers. Gas sorption studies of modified PIMs showed that the sorption capacities of polymer altered depend on the modification. Hydrolysed PIMs showed reduced CO2 uptake. Ethanolamine modified PIM showed reduced CO2 uptake along with even more reduced N2 uptake, leading to enhanced CO2/N2 ideal selectivity at 1 bar. Amine modification increased the CO2 uptake of the polymer, while showing the same N2 uptake. Enhanced sorption selectivity was also achieved by amine PIM-1. Although chemical modifications reduced the permeability of the membranes, enhanced gas selectivity was obtained. Enhanced H2/CO2 selectivity placed amine PIM-1 above the 2008 Robeson upper bound. The relationship between the degree of conversion and permeability of amine PIM-1 was studied in detail. The effect of temperature and pressure on the permeability of amine PIM was studied, using several different temperatures and pressures. Ethanolamine modified PIM showed size selective behaviour by enhanced H2/N2 and H2/CH4 selectivities, and it crossed the 2008 Robeson upper bounds. Dye adsorption studies revealed that chemical modification manipulated the interaction ability of PIM-1. PIM-1 showed high affinity for neutral dye. While hydrolysed PIMs showed high affinity for cationic species, amine and ethanolamine modified PIMs displayed high affinity for anionic dyes. The factors affecting the uptake capacity of PIM-1, including temperature and pH, were studied along with kinetics of dye adsorption. Thermal treatments of modified PIMs and their structural characterisation were performed. The adsorption and separation performances of thermally treated and untreated modified PIMs were compared.

The benefits that altruistic behaviours, emotional intelligence (EQ) and intrinsic motivation have on organisations are increasingly becoming observable and enticing greater insights into these constructs, especially from the perspective of leaders. Moreover, the increase in the effectiveness of leaders across all of these constructs enables greater employee performance, from both the perspective of leaders and their followers, which results in increased organisational profitability. The primary objective of this research study was to investigate the relationship between the three constructs of altruistic behaviour, EQ and intrinsic motivation amongst leaders in South African organisations. This study also attempted to determine whether intrinsic motivation has a mediating effect on EQ and altruistic behaviours. Moreover, this study wishes to identify demographic differences in terms of the responses to the items related to each of the constructs. The questionnaires employed by this study was administered to leaders (n=136) who currently work in South Africa. Positive and statistically significant relationships were found amongst these constructs, implying that, an increase in one of these constructs will result in an increase in another. However, there was no sufficient evidence in support of mediating effect of intrinsic motivation on EQ and altruistic behaviours. The confirmatory factor analysis was able to validate all three measuring instruments used to assess the constructs from a South African perspective. The present study was unable to identify any demographic differences for the Adapted Self-Report Altruism Scale and Intrinsic Work Motivation Scale and was only able to identify demographic differences by the Schutte Self-report Emotional Intelligence Test as a whole and the perception of emotion scale. The study encountered some limitations. Firstly, the researcher encountered a difficulty in finding appropriate literature on the constructs. Secondly, the study obtained a small sample size (n=136). The reason for this is that the target sample chosen by the researcher, namely leaders in organisations, proved to be a challenging sample because many leaders were not able or willing to complete the questionnaire due to their heavy workload and strict deadlines. Thirdly, given that three measuring instruments were used to gain the data needed for this study, the total number of items came to 136. This could mean that the questionnaire may have been burdensome to complete and it would take approximately 15 minutes to complete. In addition, factors such as biased responses, as well as personal and environmental factors on the part of the respondents all posed limitations to this study in that it may have influenced the responses given by the sample. The results obtained by this study suggests that the higher the level of EQ of leaders, the higher the likelihood that they will be intrinsically motivated and exhibit altruistic behaviour. As explained by exchange theory, if one is conditioned to be “good”, the likelihood of partaking in altruistic behaviour is enhanced (Bar-Tal, 1986). If an organisation creates a culture of altruistically helping others in the workplace and the community, the possibility of creating a “habit” of exhibiting altruistic behaviour could result. The benefits of creating this altruistic culture could be far-reaching. The researcher encourages organisations to measure and identify the level of EQ of their leaders and provide development opportunities should this be lacking. This is because, as identified by Barbuto and Burbach (2006), in order for leaders to achieve support from their followers, it is crucial that they develop a high reliance on their empathy to identify with the feelings and emotions of their followers. It is important to note that the results of this study was analysed in June 2016 and is based only on 136 leaders across some industries of South Africa. It is suggested that the results of this study to be validated in the South African context by additional empirical research that tests the hypothesis identified in this study to ascertain whether the results of the current study can be replicated and applied broadly. It is advised that the study is tested over a longer period, in different industries and across various countries. This is so that increasing value can be added to this field of research.