As the number one cause of sick absenteeism and disability pension, musculoskeletal pain is considered a major health problem in Sweden and many other industrialized countries. Medical findings are often insufficient to explain the pain’s intensity or duration, and psychological factors are known to be important in understanding the aetiology and maintenance of pain. The current thesis examines the relationship between non-specific chronic musculoskeletal pain and cognitions, emotions and behaviours. In Study I, chronic pain patients were interviewed about pain experiences and the results indicated that some patients use psychological defences to deal with chronic pain. Study II was an experimental approach set up to study the association between chronic pain and selective memory. In a pictorial memory game, no differences were found between patients and controls in the neutral game. In the pain-related game patients decreased – and controls improved – their performance, a finding discussed in terms of cognitive avoidance. Study III used questionnaire and register data to examine the predictive value of psychosocial variables on sustained pain-related sick absenteeism and the results showed sense of mastery and recovery beliefs to be especially important. The studies are discussed in terms of emotional and defensive coping and it is suggested that defences can be related to excessive activity, which may increase the risk of future relapses. It was suggested that an increased acceptance of pain, at both an individual and a societal level – would favour rehabilitation and return-to-work for those suffering from persistent pain.

The objective of this thesis was to investigate the effects of mammalian grazers, such as microtine rodents and reindeer, (top-down effects) and nutrient availability (bottom- up effects) on the plant community of a tundra heath. I conducted a large-scale fertilization experiment and studied the impact of grazers using exclosures. I measured the effects of fertilization and grazing on soil microbial activity and nutrient cycling. I investigated the responses to fertilization of the invertebrate community, I studied the effects on the quality of bilberry as food for mammalian herbivores, and I looked at how concentrations of nutrients and carbon-based secondary defences against herbivory fluctuated between seasons in unfertilized and fertilized treatments. The results of my thesis show that the plant community investigated is exposed to a strong top-down control by mammalian herbivores. On the fertilized and grazed areas the aboveground biomass of the vascular plant community did not increase compared to unfertilized areas. However, the productivity of the plant community was clearly nutrient- limited. During the eight years of the experiment, on the fertilized areas plant biomass was significantly increased inside the herbivore exclosures In my study mammalian herbivores at comparatively low densities and grazing outside the growing season were sufficient to control the biomass of a heterogeneous plant community. Microtine rodents (Norwegian lemmings and grey-sided voles) preferred the fertilized areas for overwintering. The food plant quality of bilberry for grey-sided voles was improved on the fertilized areas throughout the year. Grazing decreased the nitrogen storage in the aboveground plant biomass. Reindeer and rodents had also important indirect effects on the plant community by decelerating soil nutrient cycling and soil microbial activity. This effect may be accelerated by the impact of herbivore on plant species composition. Graminoids, which contained the highest nitrogen concentrations in their tissues, increased rapidly on the fertilized areas, but their abundance was significantly lower on grazed fertilized areas. The invertebrate community was detritus-based and received their energy indirectly from the litter via soil microbes and detritivores. Fertilization increased the biomass of invertebrate carnivores, but had no effect on the biomass of invertebrate herbivores. Apparent competition between detritivores and invertebrate herbivores, mediated by carnivorous invertebrates predating on both of them, is supposed to keep the densities and grazing pressure of invertebrate herbivores low. Grazing damage by invertebrates was very low and only 0.021 % of the total vascular plant biomass was removed. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 2001, härtill 6 uppsstser.</p> / digitalisering@umu

Le biofloc est un système d’élevage intensif avec un faible renouvellement d’eau ; ainsi se développe une population diversifiée de micro-organismes (micro-algues, zooplanctons et bactéries) associée à de la matière organique qui forme les floculats. Ces derniers jouent le double rôle de filtre biologique et de complément alimentaire. Cette thèse a pour objectif de mieux comprendre le fonctionnement de ce système d’élevage et ses interactions avec la crevette Litopenaeus stylirostris. Dans cet objectif général s’inscrit deux objectifs plus spécifiques : (i) mesurer les gains zootechniques apportés par l’élevage en biofloc (ii) étudier les interactions trophiques entre le milieu d’élevage et la crevette en lien avec les performances zootechniques. Nos résultats montrent des gains relatifs de l’élevage en biofloc aux niveaux de la survie, de la croissance, des performances de reproduction des femelles et de la qualité de leur progéniture. Ces meilleures performances s’expliquent par la contribution de la productivité naturelle, estimée entre 37 et 40%, dans l’alimentation de la crevette. Ce complément d’aliment, outre d’être toujours disponible dans le milieu d’élevage, apporte de l’énergie, des nutriments et des molécules bioactives. L’aliment naturel représente une source nutritive de lipides, particulièrement riche en phospholipides et en acides gras polyinsaturés, qui sont essentiels pour la reproduction et le développement des larves en phase de lécitotrophie ; ces lipides sont accumulés dans la glande digestive et les œufs des femelles élevées en biofloc. L’aliment naturel est également une source de glutathion, puissante molécule antioxydante, qui contribue au renforcement du système des défenses anti-radicalaires de la crevette et protège les lipides insaturés de la peroxydation, une cause du stress oxydant. Les bactéries sont prépondérantes dans la productivité naturelle d’un élevage en biofloc et contribuent donc à l’alimentation de la crevette. Aussi, dans le dernier volet de cette thèse, nous avons caractérisé la diversité taxonomique et l’abondance des bactéries du milieu d’élevage et montré son influence sur le microbiote intestinal des crevettes. De façon générale, nous observons une meilleure santé des animaux élevés en biofloc qui se traduit par une régulation positive des gènes impliqués dans l’immunité et les défenses anti-radicalaires après un stress au peroxyde d’hydrogène. Ainsi, les effets positifs de l’élevage en biofloc sur les survies, les croissances et la reproduction ont pour origine le complément d’aliment apporté par la productivité naturelle / Biofloc is an intensive rearing system with zero or minimal water exchange where a diverse population of microorganisms (microalgae, zooplankton and bacteria) develops in association with organic matter to form the floc particles. These particles play the double role of biological filter and dietary supplement. This dissertation aims to better understand the process of this rearing system and its interactions with the Litopenaeus stylirostris shrimp. Two specific objectives were integrated within the framework of this general objective: (i) to measure the production gain from biofloc rearing and (ii) to study the interaction between biofloc environment and shrimp and to assess its role on production performances of shrimps. Thus, our results show production gains of shrimp reared in biofloc in terms of survival, growth, reproductive performances and quality of larvae. This better performance can be explained by the contribution of natural productivity, estimated between 37 and 40%, in shrimp food. This food supplement, constantly available in the environment, provides energy, nutrients and bioactive molecules. The natural productivity represents a source of lipids, in particular of phospholipids and polyunsaturated fatty acids, which were essential for the reproduction and development of larvae during the lecitotrophic stage; these lipids were accumulated in digestive gland and eggs from females reared in biofloc. The natural food is also a glutathione source, a powerful antioxidant molecule, which contributes to strengthen antioxidant defense system of shrimps and protects lipids against peroxidation, a cause of oxidative stress. Bacteria were dominant in natural productivity of biofloc environment and contribute to shrimp food. Thus, in the last part of this dissertation, we characterized the taxonomic diversity and abundance of bacteria in biofloc environment and showed their influence on shrimp intestinal microbiota. Generally, we observed a better health of biofloc resulting in up-regulation of the studied genes involved in immunity and anti-radical defenses after oxidative stress with hydrogen peroxide. The positive effects of biofloc rearing on survival, growth and reproduction originate from food complement provided by natural productivity.

Summaries in Afrikaans and English / Text in Afrikaans / 'n Kort elementologiese uiteensetting vir strafregtelike aanspreeklikheid word gevolg deur bewysregtelike begrippe wat van toepassing is op vermoedens by toerekeningsvatbaarheid. Die historiese regsposisie asook die ontwikkeling in die huidige Suid-Afrikaanse reg met betrekking tot geestesongesteldes, kinders en persone wat 'n verweer van nie-patologiese ontoerekeningsvatbaarheid insluit, word bespreek. Daar word gekonsentreer op ·die ontwikkeling van 'n algemene verweer van niepatologiese ontoerekeningsvatbaarheid. Die konstitusionele reg, vennoedens en ontoerekeningsvatbaarheid word aan die hand van Suid-Afrikaanse regspraak en die Interim Grondwet bespreek. Daar word na buitelandse reg gekyk ten einde 'n aanbeveling te kan maak wat grondwetlik nie sal indruis op die reg van die individu tot onskuld nie. 'n Algemene verweer van nie-patologiese ontoerekeningvatbaarheid word onderstellll mits dit met omsigtigheid deur die howe benader word. Die arbitrere ouderdomsgrens vir vasstelling van toerekeningsvatbaarheid by kinders word gekritiseer en 'n verhoorbaarheidvasstellingseenheid word aanbeveel. / A short elementological discussion of criminal responsibility is followed by concepts of law of evidence that is applicable to presumptions of accountability. The historical legal position as well as the development in the current South African law and the present legal position with reference to the mentally disturbed children and persons with a defence of non-pathological unaccountability are included and discussed. The constitutional law, presumptions and unaccountablility are discussed with reference to the South African case law and the Interim Constitution. Foreign law is perused so that a recommendation could be made that would not interfere with the rights of the individual to be deemed innocent. A general defence of non-pathological unaccountability is supported if it is treated with the necessary circumspection by the courts. The arbitrary age boundaries for the determination of accountability in children is critized and a unit to determine trialability for pathological and non-pathological accountability is recommended. / Criminal & Procedural Law / LL.M.

<p>Denial of Service and the Distributed Denial of Service Attacks have recently emerged as one of the most newsworthy, if not the greatest, weaknesses of the Internet. This paper attempt to explain how they work, why they are hard to combat today, and what will need to happen if they are to be brought under control. It is divided into eight sections. The first is an overview of the current situation and also brief explanatory of the rest of the chapters being covered. The second is a detailed description of exactly how this attack works, and why it is hard to cope with today; of necessity it includes a description of how the Internet works today. The third section is totally about the different attacks in recent years and how they affected the people or the bigorganizations. The fourth section describes the short-term prospects, the tools which are used to rectify these attacks. The fifth is problems being faced with an explanatory of the percentage of attack in recent years and comparing the problems. The sixth is what can be done today to help alleviate this problem. The seventh section describes the legal actions and also legal actions that can be followed against the attack by the victim; and the eighth section describes the long-term picture, what will change to bring this class of problem under control, if not eliminate it entirely. And finally there are some appendices: a bibliography, giving references to original research work and announcements; a brief article on securing servers; and acknowledgments for the many people who helped make this paper possible.</p>

Idag är det kustnära eller det s.k. litorala området i fokus för många av världens mariner. Det finnsolika syften med att genomföra operationer i det litorala området men det huvudsakliga syftet äratt tillse att sjötransportförbindelserna som till största del sker i det litorala området fungerar.Andra syften är t.ex. att med expeditionära styrkor kunna påverka en situation på land eller somSverige operera i det litorala området i syfte att försvara sig. De uppgifter som ska lösas i detlitorala området inkluderas av begreppet Littoral Warfare, men vad betyder det för de olikanationerna?Denna uppsats jämför hur USA, Storbritannien och Sverige ser på det litorala området ochbegreppet Littoral Warfare. Undersökningen kopplas till vilka målsättningar nationerna har inomdet litorala området, vilka metoder de avser nyttja samt vilka medel som finns att tillgå för att lösauppgifter i det litorala området. Undersökningen genomförs genom att jämföra de olikanationernas doktriner för att ge ökad förståelse av begrepp som används i gemensammaoperationer och med avsikt att minska risken för missförstånd.Undersökningens resultat visar att nationerna har samma uppfattning avseende vad begreppetLittoral Warfare innebär men att uppfattningen om vilket det litorala området är skiljer sig.Målsättningarna mellan nationerna är till viss del också särskiljande då t.ex. Sverige har en merdefensiv hållning än de andra nationerna. Skillnader som framkommer avseende val av metod ärmer en resursfråga än vilka mål nationen vill uppnå i det litorala området. / Nowadays, the coastal and littoral areas are in focus for most of the navies and marines in theworld. There are a number of different purposes for a navy to conduct littoral operations. Onepurpose could be to ensure functioning sea lines of communication, which most times areestablished in this part of the sea. Another purpose could be to influence the situation ashore withan expeditionary force. Furthermore, the littoral area could be used to defend a nation, which is thecase in Sweden. Missions and tasks supposed to be conducted in the littoral areas are gatheredunder the heading of Littoral Warfare, but what does this term imply for different nations?This research compares how the US, Great Britain and Sweden views the littoral area and the termLittoral Warfare. The research is connected to what objectives these nations have in the littoralarea, what methods they intend to use and what means they have available to accomplish theirobjectives. In order to increase the knowledge for the different terms used in combined jointoperations and to minimize the risk of misunderstanding, this research is comparing the doctrinesof the nations mentioned above.The result of this comparison shows that these nations have the same general understanding of theterm, Littoral Warfare, but their notions on the actual area considered as littoral are divergent.Furthermore, there is some diversity between the nations regarding their objectives where Swedenfor instance, has a more defensive approach compared to the others. Finally, the differences thatcomes to light regarding what methods to use in the littoral area, depends on what means areavailable, more so than the objective itself. / Avdelning: ALB – Slutet Mag. 3 C-upps. Hylla: Upps. ChP 07-09

Denial of Service and the Distributed Denial of Service Attacks have recently emerged as one of the most newsworthy, if not the greatest, weaknesses of the Internet. This paper attempt to explain how they work, why they are hard to combat today, and what will need to happen if they are to be brought under control. It is divided into eight sections. The first is an overview of the current situation and also brief explanatory of the rest of the chapters being covered. The second is a detailed description of exactly how this attack works, and why it is hard to cope with today; of necessity it includes a description of how the Internet works today. The third section is totally about the different attacks in recent years and how they affected the people or the bigorganizations. The fourth section describes the short-term prospects, the tools which are used to rectify these attacks. The fifth is problems being faced with an explanatory of the percentage of attack in recent years and comparing the problems. The sixth is what can be done today to help alleviate this problem. The seventh section describes the legal actions and also legal actions that can be followed against the attack by the victim; and the eighth section describes the long-term picture, what will change to bring this class of problem under control, if not eliminate it entirely. And finally there are some appendices: a bibliography, giving references to original research work and announcements; a brief article on securing servers; and acknowledgments for the many people who helped make this paper possible.

The object of this thesis was to study plant community structure, especially in relation to vertebrate herbivory, in an altitudinal gradient in the Fennoscandian mountain chain. A sowing experiment in a high alpine Ranunculus glacialis population showed that seeds germinated better in cleared microsites than under established individuals. This is contrasted with a hypothesis that predicts positive plant-plant interactions in high alpine environments. It was concluded that plant-plant interactions in die studied population varied from neutral to negative, whereas no indications for positive interactions were found. An exclosure experiment in a snow-bed showed that a lemming population consumed 33 % of the available graminoids and 66 % of the mosses from August to June during a population peak. The results shows that grazing needs to be considered as a structuring factor in snow-bed vegetation. The vegetation in exclosures in another snow-bed changed from a graminoid-dominated to a herb-dominated plant community during a long-term (six years) experiment No changes of the same magnitude were seen in a tall herb meadow on a lower altitude. Survival of transplanted adult shoots from the tall herb meadow was equally high in the snow-bed as on the meadow, and germination was also high on bare ground in the snow-bed. Grazing seemed to be a more important structuring factor in the snow-bed than in the more productive tall herb meadow. Raising the grazing pressure during one growing season by introducing microtine rodents into enclosures did not cause any large short-term effects on plant community structure in a tall hob meadow or in a snow-bed. Marked shoots showed that some preferred plant species had a high shoot mortality, but biomass for pooled categories of plants was not significantly affected. It was predicted that the tall herb meadow would be more grazing sensitive than die snow-bed, but productivity on the meadow seemed to be sufficiently high for the plants to compensate for the grazing during the growing season. A greenhouse experiment showed that voles, when grazing freely, have the potential to deplete productive field layer vegetation contrary to predictions from plant defence theories. A nitrogen-based defence did not prevent heavy shoot mortality for toxic tall herbs. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 5 uppsatser.</p> / digitalisering@umu.se

Disturbances, such as herbivory and fire are commonplace in savanna ecosystems. The effects of herbivory and fire on growth and defences of adult trees is a much studied filed in plant ecology. However, there are comparatively few studies that have investigated the effects of herbivory and fire on seedling growth, defences and establishment. African Acacia trees are common and widespread, and are suggested to be keystone species in savanna ecosystems. They have been shown to significantly positively increase soil characteristics, such as soil moisture and infiltration, while also increasing spatial heterogeneity of savannas. These trees are distinguishable by their array of physical and chemical defences. Physical defences are either in the form of spines (physiologically costly to produce, thus considered inducible) or prickles (physiologically cheap to produce, thus considered constitutive), while condensed tannins are the most common form of chemical defences. Adult Acacia trees have been shown on several occasions to be highly resilient to disturbance events, primarily due to their large size. However, the effects of herbivory and fire on Acacia seedlings have been little studied despite their apparent importance for our understanding of African savanna ecosystem functioning. In two separate experiments, this thesis aimed to investigate the individual and combined effects of simulated herbivory and fire on the regrowth, defences, and total non-structural carbohydrates (TNC) of the seedlings of several Acacia species, while also testing the Resource Availability Hypothesis (RAH) (14 Acacia species) and the Expanded Growth-Differentiation Balance Hypothesis (GDBH) (three Acacia species). The RAH (Coley, Bryant & Chapin 1985) and the GDBH (Loomis 1932) both assume that arid-adapted (resource-poor) species are slow growing, with low tissue turnover rates. Contrastingly, humid-adapted (resource-rich) species have fast growth rates and thus a high tissue turnover rate. Therefore, arid-adapted species are predicted to invest more carbohydrate reserves in defence after a disturbance event, in order to defend new photosynthetic material. Conversely, humid-adapted (resource-rich) species are predicted to invest carbohydrate reserves into increased growth after a disturbance event, in order to compensate for tissue loss. The first greenhouse experiment found that, in accordance with the RAH, humid-adapted species displayed elevated growth rates compared to arid-adapted species. Overall, defences significantly increased after herbivory, but significantly decreased after fire. Herbivory was also shown to significantly reduce TNC stores in roots more than fire. We found that arid-adapted species did indeed invest more carbohydrate stores (TNC) into defence, and displaying an increase in spine and prickle abundance, spine and prickle length, and condensed tannin concentration. Humid-adapted species displayed an increase in growth rather than in defence, with the majority of species only increasing one defensive trait. Humid-adapted species also displayed significant trade-offs (negative correlations) between new stem growth and defence traits, while arid-adapted species overall did not display any significant trade-offs between stem growth and increased defences. The majority of arid-adapted species also displayed an allometric effect for spine abundance and length, with an increase in one trait led to an increase in the other. Prickles were found to be inducible, despite the assumption that due to low physiological cost, they are no inducible. Herbivory and fire were shown to not be substitutable in their effects on Acacia seedlings in a controlled experimental setting. The second greenhouse experiment tested the Expanded Growth-Differentiation Balance Hypothesis (GDBH) in the seedlings of A. erioloba, A. karroo, and A. nilotica using five levels of nutrient availability. Overall, spine abundance and spine length displayed a unimodal trend in all three species, with spine abundance and spine length being greatest at a nutrient availability of 800 mg/ ℓ. Spine abundance, spine length and condensed tannins increased significantly after herbivory, but were shown to significantly decrease after fire. We found that with an increase in nutrient availability, the growth of stems and roots, along with the production of TNC in roots and stems of all species significantly increased. Our data provide mixed support for the assumptions and predictions of the expanded GDBH. The regrowth of stems and physical defences were consistent with the GDBH. Chemical defences (i.e. condensed tannins) were however, inconsistent with the predictions of the GDBH. We have shown that Acacia seedlings are highly resilient to disturbance events, while the growth responses of Acacia seedlings are underpinned by TNC stores in roots. Simulated herbivory and fire are often substituted for one another in controlled experiments. However, we have shown that the effects of herbivory and fire have significantly different effects on regrowth patterns of Acacia seedlings. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Five potential resistance-inducing chemicals were applied to two sugarcane varieties (N12 and N27) in a pot trial with the aim of inducing resistance to nematodes in naturally-infested soil. BION® (acibenzolar-S-methyl), methyl jasmonate, cis-jasmone and 2,6-dichloroisonicotinic acid (INA) were applied as a foliar spray and suSCon® maxi (imidacloprid) applied to the soil. All chemicals were tested at two rates and plants were sprayed one week prior to being harvested at 7, 9 and 11 weeks of age. Meloidogyne and Pratylenchus infestation of sett and shoot roots was determined at each harvest. The activity of four pathogenesis-related proteins was examined at 7, 9 and 11 weeks using separate assays, these enzymes where chitinase, β-1,3-glucanase, peroxidase and polyphenol oxidase. Methyl jasmonate treatment produced significant increases in β-1,3-glucanase, chitinase and peroxidase activity. All other elicitor treatments showed little difference in enzyme activity from the Control. The effect of each treatment on plant growth was examined by recording the dried root and shoot biomass of each plant. No significant differences were seen (p<0.05; Holm-Sidak test). However, root and shoot dried biomass was highest in the N12 variety treated by suSCon® maxi. The infection of sugarcane with Ustilago scitaminea (sugarcane smut) is commonly identified visually by the presence of a smut whip. Identification of sugarcane smut infection can be determined prior to whip development by staining tissue sections with lactophenol cotton blue and examining plant tissues microscopically. This allows for a rapid determination of smut infection which can aid breeding programs. Smut infection is achieved in vitro by soaking sugarcane setts in smut spores collected from infected whips. Four methods of inoculation were examined. The method that most consistently caused infection involved allowing setts to germinate for 24 hours, before puncturing a bud with a toothpick, followed by submerging the sett in 1x10⁸ smut spores per mℓ. An elicitor of systemic acquired resistance called BION®, and an insecticide with resistance-inducing properties called Gaucho® (imidacloprid) were used as a sett soak treatments to induce resistance to sugarcane smut. The effect of each treatment at three concentrations on plant germination and growth was examined in the NCo376 variety. Smut spore germination on agar was examined in the presence of both treatments at three concentrations. Sugarcane setts were treated with a concentration that did not significantly reduce the germination of smut spores or sugarcane setts. Plants were infected with smut post treatment and allowed to grow for approximately one month until plants were between 8 and 10 cm in height. Smut infection was assessed by cutting longitudinal sections through the base of the shoot and staining each section with cotton blue lactophenol. Treatment with BION® and Gaucho® did not reduce smut infection. / M.Sc.Agric. University of KwaZulu-Natal, Pietermaritzburg 2013.