Information technology (IT) can be used to empower an organization to enable it to continue evolving. One aspect in which an organization can evolve is in the form of information security. Previously, information security has been seen as a concern only for the IT-department. However, as the number of threats towards information has rapidly grown over the years, the concern for information security has also increased. The issue on how to keep information safe from unauthorized people has become more important as well as questioned over the years. During the last decades, the concept of information security has evolved to become a multi-dimensional concern affecting entire communities, societies, and organizations. This means that information security has been managed differently in the past, but today, new and other measures are required to ensure the secrecy of certain information. Due to this, organizations are forced to implement certain measures to counter these threats, but what are the effects of this? This thesis compares three different organizations over three different sectors and the purpose is to investigate the effects information security might have within an organization as well as how these effects are managed. With a focus on policies, training, and education of employees as well as the employee awareness, this thesis aims to answer how organizations see information security. Further, it aims to find out what consequences these effects have on their daily work. The results from this study have shown that increased security measures need to be highly motivated and in continuous dialogue with the employees to bring incentives for further use of the measures. An increase in information security can have a damaging effect on efficiency. Therefore, it is important that the organization is able to ensure the desired effect of increased security. With larger openness and accessibility, employees will have easier and quicker access to the information needed, which is essential for the effectivity within the organization, as well as higher incentives for attacks and malpractice of information. / Denna uppsats jämför tre olika organisationer verksamma i olika sektorer, syftet är att undersöka effekterna  informationssäkerhet kan ha på en organisation men även hur dessa effkter är hanterade.  Med fokus på policy, träning av anställda men också medvetenheten så siktar denna uppsats på att svara på hur organisationer ser informationssäkerhet. Den kommer också att försöka hitta vad konsekvenserna av informationssäkerhet i det dagliga arbetet.  Resultatet från denna studie visar att ökad informationssäkerhet måste vara motiverat och i konstant dialog med användarna och implementera incitament för att öka motivet. Ökad informationssäkerhet kan ha en skadande effekt på effektiviteten, därför är det viktigt att organisationerna får den önskade effekten de vill av den ökade säkerheten. Genom mer transparans och tillgänglighet så medför det också att anställda har lättare att hitta rätt information som behös vilket är nödvändigt för effektivitet inom organisationen, men detta ökar även incitament för olika typer av attacker och misskötsel av information.

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Abstract The most important paradigms in quantum mechanics are probably a twolevel system, a harmonic oscillator and an ideal (infinite) periodic potential. The first two provide a starting point for understanding the phenomena in systems where the spectrum of energy levels is discrete, whereas the last one results in continuous energy bands. Here an attempt is made to study the dynamics of the electrons in a narrow miniband of a semiconductor superlattice under electric and magnetic fields. Semiconductor superlattices are artificial periodic structures, where certain properties like the period and the energy band structure, defined in standard crystals by the nature, can be controlled. Electron dynamics in a single superlattice miniband is interesting both from the viewpoint of fundamental and applied physics. From the fundamental perspective superlattices serve as a model system for a wealth of phenomena resulting from the wavenature of charge carriers. On the other hand, superlattices can potentially be utilized in oscillators and amplifiers operating at THz frequencies. They can, in principle, provide a reasonable THz Bloch gain under dc bias and parametric amplification in the presence of ac pump field. Because of numerous scientific and technological applications in different areas of science and technology, including astrophysics and atmospheric science, biological and medical sciences, and detection of concealed weapons and biosecurity, a construction of compact tunable THz amplifiers and generators that can operate at room temperature is an important – but so far unrealized – task. This thesis focuses on the influence of electric and magnetic fields on small-signal absorption and gain in semiconductor superlattices in the presence of dissipation (scattering). We present several new ideas how the effects arising due to the wave nature of the electrons can be utilized in an operation of THz oscillators and amplifiers. In Papers I–V, we discuss the properties of superlattice sub-THz and THz parametric amplifiers, whereas the Papers VI–IX are devoted to the problem of domain instability in the realization of cw THz Bloch oscillator. In Paper IX we also establish a feasibility of new type of superlattice THz amplifier based on nonlinear cyclotron-like oscillations of the miniband electrons. The ideas presented in the Papers I–IX are supplemented here with a detailed discussion of the physical origin of the effects and more rigorous mathematical derivations of the main equations.

This thesis aims to see how individual and partner’s unemployment affect self-rated depressive symptoms, both for individuals separately, and for individuals in a relationship within Europe. The research questions were examined by using European Social Survey (ESS) data from 2014. An index was created in order to capture the phenomena of depressive symptoms. To investigate the effect of unemployment in relation to self-rated depression, multiple regressions analysis were used. The results show that there is a relationship between unemployment and depressive symptoms, for both men and women. However, men tend to be affected by their own unemployment only, whereas evidence was found supporting that having an unemployed partner affect depressive symptoms in a negative way for women. Hence, women are a more vulnerable group on the labour market, because they are not only affected by their own labour market status, but also by the labour market status of their partners.

The coal industry of Mpumalanga Province is faced with the problem of developing cost effective ways of using large volumes of calcium and magnesium sulphate enriched waste waters. Use of the waste waters for agricultural production may contribute as a stabilising factor with regard to yields in this high potential agricultural area. The objectives of this study were to determine the effect of such waste waters on yield and to compare crop response to calcium and magnesium sulphate salinity at different nutrient levels. Two separate glasshouse experiments were conducted. Wheat (Triticum aestivum L. cv. SST 825) was grown in calcium and magnesium sulphate salinised nutrient solutions (Ca:Mg 2: 1) with differential levels of NO3, NH4, P and K. A soil pot experiment was subsequently conducted with maize (Zea mays, cv. PAN 6256), three gypsum and magnesium sulphate salinity levels and a 6 x 2 x 3 factorial combination of N, P and K. Calcium and magnesium sulphate salinity decreased the biomass production of both crops. This was mainly due to interactions of Mg with the uptake of essential nutrients in wheat and a Mg toxicity andlor Ca deficiency induced by high levels of Mg andlor SO4 in maize. The application of NO3, NH4, and K at rates different from the level considered beneficial for non-saline conditions improved wheat growth under sulphate saline conditions. Strongly inhibitory salinity levels controlled the maize yield of the highest salinity treatment regardless of the level of fertiliser application. A beneficial effect of higher NH4 supply was observed in both experiments. This can be ascribed to the antagonistic effect that NH4 exerted on Mg concentrations in plants (both experiments) and SO4 (soil pot experiment) and/or to a higher N-utilization efficiency where N was supplied as NH4 compared to NO3. Differential application levels of P had no effect on the yield of wheat. Phosphorus concentrations in maize were marginal to low, even at extremely high soil Bray I-P levels. This was probably caused by the precipitation of P as insoluble calcium phosphate complexes in the soil andlor between the free space of the cortex cells of plant roots. These results could also indicate that the Bray I extraction method does not give a true reflection of plant available P in sulphate saline soil. Further experimentation is needed to verify these results under field conditions and determine the optimal rate, method and timing of especially NH4 and PO4 fertilisers when irrigating crops with these calcium and magnesium sulphate enriched waste waters. / Dissertation (MSc (Plant Production and Soil Science))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

Magister Scientiae - MSc / This thesis aims to measure the rate of radon loss from water in a systematic way. The dependence on surface area, temperature and concentration will be investigated. The experiments were done at UWC by creating radon using radium sources and then measuring the radon concentrations inside a vacuum chamber to obtain the speed of radon escape from the water. The results are compared to a model [Cal 2002] where the radon concentration in the air and hence the transfer rate is measured using a RAD7 radon detector. Since the equations cannot be solved analytically, a numerical solution is employed. The radon transfer velocity coefficient is found to be (1.9±0.5)×10-6m/s. This value indicates that the escape of radon should not be a problem when a sample is open to the air for a minute or two. / South Africa

Diazoxide, a non-diuretic benzothiadiazlne antihypertensive agent, is thought to act directly upon the vascular smooth muscle of the resistance vessels to exert its therapeutic effects in hypertension. Diazoxide may exert its antihypertensive action by antagonizing calcium in vascular smooth muscle. Wohl et al. (1967 and 1968) have suggested such an interaction based on experiments conducted with isolated rabbit aortae. The present experiments were designed to investigate the possible cellular locus of the postulated interaction of diazoxide with calcium using the isolated anterior mesenteric vein of the rabbit as a model of vascular smooth muscle. This vein is spontaneously motile and possesses characteristics similar to those observed for vessels of the microcirculation. Diazoxide at 10ˉ⁴ M inhibited spontaneous motility and its associated membrane electrical activity, and caused hyperpolarization in rabbit anterior mesenteric veins examined with a sucrose gap apparatus. Diazoxide also inhibited spontaneous electrical and contractile activity in guinea-pig taenia coli and in estrogen dominated rabbit uterus. In all these tissues, calcium is believed to play an important role in spontaneous electrical membrane activity. Diazoxide failed to affect contractility, rate of spontaneous contractions, or action potential configurations in isolated rabbit heart, even though the action potential in heart tissues possesses a definite calcium current component. Diazoxide reduced contractions induced in the mesenteric vein by electrical stimulation of the smooth muscle itself or by excitation of the nerve endings within the vein. Various drugs were chosen for their ability to contract the mesenteric vein in different ways. Noradrenaline contracts vascular smooth muscle even when the tissue Is depolarized with ouabain Diazoxide failed to inhibit noradrenaline contractions in the depolarized vein, but showed the characteristics of a competitive inhibitor of noradrenaline in normally polarized veins. Diazoxide was also capable of inhibiting contractions to serotonin and procaine, agents which require membrane polarization to initiate contraction. The inhibitory effect of diazoxide was not observed to be modified in solutions containing high concentrations of calcium. Diazoxide was tested upon the contractile responses to calcium In veins depolarized in K⁺ Ringer solution. Examination of the resultant dose response curves showed that diazoxide inhibited calcium contractions ln a reversible, non surmountable manner. Hydrochlorothiazide had no effect upon calcium induced contractions. Diazoxide antagonizes drug induced contractions only if a polarized membrane is present. Calcium Induced contractions in depolarizing solutions were inhibited in an apparently Insurmountable manner, while drug responses in polarizing solutions were inhibited by diazoxide in a surmountable manner. In addition, action potentials from rabbit heart were unchanged whereas, the apparently calcium spike mediated electrical activity of certain smooth muscles is inhibited. It is concluded that diazoxide affects the membrane of vascular smooth muscle to reduce excitability of the tissue to drugs or electrical stimuli. It is possible that cell membrane bound calcium could be the locus of action of diazoxide and that this agent modifies membrane calcium to cause increased membrane stability. / Medicine, Faculty of / Anesthesiology, Pharmacology and Therapeutics, Department of / Graduate

Chinese hamster V79-171B cells grown for about 24 hours in suspension culture display increased resistance to cell killing by ionizing radiation compared with cells grown as monolayers, an observation originally termed the "contact effect". More recently, development of that resistance was shown to be accompanied by changes in the conformation of the DNA which reduce its denaturation rate in high salt/weak alkali. These changes in DNA conformation, mediated by the cellular micro-environment, appear to be responsible for the contact effect. The conditions necessary for the development of the effect are not, however, completely understood. In particular, when cells grown as monolayers on petri plates are suspended in spinner culture flasks, their growth characteristics change in three distinct ways. First, cells in suspension no longer have a solid substrate, so they remain round. Second, after several hours, they begin to aggregate to form "spheroids", so that three-dimensional intercellular cell contact develops. Third, cells in the stirred suspension cultures are not subjected to high local concentrations of metabolic by-products or surrounded by a zone depleted of nutrients, as are cells in monolayer culture. The studies described here were designed to determine how each of these factors influence changes in DNA conformation, as assayed using the alkali unwinding technique. Our results indicated that a round shape may not be an essential requirement, since cells spread out on the surface of cytodex beads in suspension culture, and sparsely-seeded cells in monolayer culture demonstrated at least a partial contact effect. Three-dimensional intercellular contact does not always seem necessary for the development of the contact effect. Cells grown in a methyl cellulose matrix developed radioresistance, even though the cells formed only small clusters of less than five cells. Similarly, suspension culture cells which were prevented from aggregating by frequent exposure to trypsin, also developed the contact effect. There was no evidence that nutrient depletion plays a role in the failure of cells grown as monolayers to develop a contact effect. However, cells grown as spheroids in the presence of monolayer cells, or in monolayer cell-conditioned medium, did not display a full contact effect. This indicates a role for monolayer cell-produced factors (possibly extracellular matrix proteins) in preventing the development of the contact effect. We conclude that changes in DNA conformation and the increase in radiation resistance, seen in V79-171b cells grown as spheroids, are not the result of intercellular contact or round shape of the cells. This radioresistance appears to be the result of an absence of monolayer cell-produced factors which could control both cell shape and DNA conformation. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate

The detrimental effect of ethanol on coordinated movement and the similarity of this effect to that of pathological damage to the cerebellum or the inferior olive (10) suggests that ethanol profoundly effects the olivocerebellar system. Each cerebellar Purkinje cell (PC) displays two distinct action potential responses: the simple spike (SS), evoked intrinsicly and via the parallel fibres, and the complex spike (CS), evoked via a solitary climbing fibre (CF) which originates from the 10. Ethanol (1.5 g/kg, i.v.) was found to have no significant effect on the CS activity evoked by direct electrical activation of CFs, while it significantly reduced, in parallel, that evoked by cerebral cortex stimulation and that occurring spontaneously. In addition, ethanol, applied both systemically and locally by micropressure, reduced the spontaneous activity of inferior olive (10) neurones. These results strongly suggest an action of ethanol local to the 10 nucleus, perhaps by a direct action on the 10 neurones themselves. Elimination of spontaneous CS activity by the electrolytic lesioning of the contralateral 10 did not significantly alter spontaneous SS firing rate. However, subsequent administration of ethanol i.v. did produce a significant increase of SS rate, indicating that only part of ethanol-evoked SS rate increase is dependant upon the reduction of CS activity. Simple spike regularity was not significantly altered by either 10 lesioning or i.v. ethanol. Ethanol applied locally to PC's by micropressure was found to reduce the period of inhibition evoked by local stimulation of the cerebellar cortex in the majority of the cells tested. This result is in agreement with the previously reported effects of intravenous ethanol on this inhibition, thought to be mediated by gamma-aminobutyric acid (GABA). Both intravenously and locally applied ethanol antagonized the inhibition of PC's evoked by locally applied GABA. These results, while in agreement, are contrary to the reported effects of ethanol in other systems. Intravenously administered ethanol did not significantly alter Golgi cell spontaneous firing, while it did significantly reduce the period of inhibition of Golgi cell firing evoked by 10 stimulation. / Pharmaceutical Sciences, Faculty of / Graduate

Workplace bullying is a repeated, health-harming mistreatment carried out in the form of verbal abuse or other ways that are threatening, humiliating, and intimidating; which interferes with work; and which prevents work from being completed (Lutgen-Sandvik & Sypher, 2009). The study sought to explore reported workplace bullying and how the phenomenon plays out as a fundamental conflict that affects the quality of life of those bullied. The study was guided by a central research question namely, what effects follow reported workplace bullying? A sub-question focused on the nature and extent of the effects of reported workplace bullying. Using the phenomenological research methodology, eight participants who reported being bullied in the workplace were interviewed. The following themes: 1) Confusion Concerning Organizational Response, 2) Fear Concerning Various Levels of Reprisals, 3) Re-bullied as Consequence of Reporting Experience, 4) Intimidation to Force Regret for Reporting Experience, 5) Alienation within the Workplace, 6) Hopelessness and Helplessness about Conditions in the Workplace, and 7) Physical and Emotional Stress Deranging Personal and Social Balance emerged from the findings. Based on discussions of the implications of the study, an Organizational Response Model (ORM) dealing with bullying and reported workplace bullying was developed as a prescriptive tool to compliment several groups who work with the bullying conflict.