Le diabète est une maladie grave et très fréquente. Elle est responsable de complications macrovasculaires dont l’artérite des membres inférieurs et microvasculaires dont les neuropathies périphériques. Desert hedgehog (Dhh) est l’un des trois membres de la famille hedgehog (Hh); cette protéine est notamment exprimée par les nerfs périphériques dont elle permet l’organisation structurale. Les membres de la famille Hh sont en outre impliqués dans la régulation de la physiologie des vaisseaux sanguins. Du fait de la diminution de l’expression de Dhh dans des conditions pathologiques comme le diabète, l’objectif de cette thèse a été de comprendre le rôle de cette protéine dans la physiopathologie des complications vasculaires associées au diabète. Nous avons montré d’une part que le défaut de Dhh altère la survie des nerfs en condition ischémique et ainsi entraîne un défaut de production par le nerf des facteurs pro-angiogéniques nécessaire à la réparation musculaire. D’autre part nous avons mis en évidence que le défaut d’expression de Dhh dans le nerf diabétique est responsable de la perte de l’intégrité de la barrière nerf-vaisseau et en conséquence de la neuropathie diabétique. Dhh apparait donc comme un nouvel acteur important du cross-talk nerf-vaisseau. La compréhension de sa fonction et de sa signalisation en font un candidat intéressant pour le développement de nouvelles stratégies thérapeutiques (thérapie génique Dhh, agonistes de la voie Hh) dans le traitement des complications du diabète. / Diabetes is a serious and frequent illness. It is responsible for macrovascular complications such as peripheral arterial disease and microvascular complications such as peripheral neuropathy. Desert Hedgehog (Dhh) is one of the three hedgehog (Hh) family members; this protein is expressed by Schwann cells of peripheral nerves and is necessary to orchestrate the organisation of nerve sheaths (i.e. Epi-, Peri-, and Endoneurium) by signaling to perineurial cells. Moreover, the Hh family members are also known to regulate blood vessel physiology. Because we found that Dhh is downregulated in pathological conditions such as diabetes, the purpose of this PhD thesis is to understand the contribution of Dhh in diabetes-associated vascular complications. We have shown that Dhh deficiency impairs peripheral nerve survival in the ischemic muscle and, by doing so, decreases the pool of nerve-derived proangiogenic factors. Then we have found that Dhh knockdown in peripheral nerves is responsible for blood nerve barrier breakdown and consequently diabetic neuropathy. Dhh appears as a new actor that plays a crucial role in nerve-vessel cross-talk. The understanding of Dhh function and signaling makes it an interesting candidate for the development of new therapeutic strategies (gene therapy, Hh agonists) in the setting of diabetic complications.

<p>In the winter of 1819 the United States shook under the first Great Depression, and on the Missouri River a great military/scientific enterprise sent to secure Missouri Territory shivered and died from cholera and scurvy. In 1820 Maj. Stephen Long and a poorly equipped expedition of twenty-three soldiers, amateur scientists, and landscape painters, set out from Engineer Cantonment to circumnavigate the unknown Central Great Plains during the height of summer, and rescue something from the debacle. After weathering endless rain and hallucinating waves of Comanche, they divided into two groups at the Arkansas, and then either starved and endured weeks of rain on the lower Arkansas, or ate rancid skunk and endured blistering sun on the 'Red River'. On return they found Long had 'mistaken' the Canadian River for the Red, and that they were yet another failed expedition to know the Louisiana Purchase. Unsurprisingly, Long labeled the whole place a "great desert." An editor improved the phrase to <i>Great American Desert</i>, and emblazoned the phrase on history.</p> <p><i>A Persistent Mirage</i> is both an exegesis of the GAD myth and an HGIS study of the groups and biomes the desert mirage occludes. Desert was a cultural term meaning <i>beyond the pale</i> that beached with the Puritans. Like Turner's frontier, it stayed a step ahead of settlement, moving west to the tall grass prairies before crossing the Mississippi to colonize the Great Plains. Once there it did calculable damage to the writing of Plains Aboriginal history. After all, who lives upon deserts but wandering beasts and savages? Beneath the mirage was an aboriginal network of agricardos, or agricultural and trading centers, growing enough food to support large populations, and produce tradable surpluses, under-girded by bison protein. Euramericans from Cabeza de Vaca on were drawn to agricardos which helped broker the passages of horses to the Northern Plains and of firearms to the Southwest. While some withstood epidemic disease, the escalation of inter-group violence and environmental degradation due to the adoption of the horse by agricardo groups proved their undoing. Beneath the Great American Desert lies the great Indian agricardo complex, with its history just begun.</p>

<p>In the winter of 1819 the United States shook under the first Great Depression, and on the Missouri River a great military/scientific enterprise sent to secure Missouri Territory shivered and died from cholera and scurvy. In 1820 Maj. Stephen Long and a poorly equipped expedition of twenty-three soldiers, amateur scientists, and landscape painters, set out from Engineer Cantonment to circumnavigate the unknown Central Great Plains during the height of summer, and rescue something from the debacle. After weathering endless rain and hallucinating waves of Comanche, they divided into two groups at the Arkansas, and then either starved and endured weeks of rain on the lower Arkansas, or ate rancid skunk and endured blistering sun on the 'Red River'. On return they found Long had 'mistaken' the Canadian River for the Red, and that they were yet another failed expedition to know the Louisiana Purchase. Unsurprisingly, Long labeled the whole place a "great desert." An editor improved the phrase to <i>Great American Desert</i>, and emblazoned the phrase on history.</p> <p><i>A Persistent Mirage</i> is both an exegesis of the GAD myth and an HGIS study of the groups and biomes the desert mirage occludes. Desert was a cultural term meaning <i>beyond the pale</i> that beached with the Puritans. Like Turner's frontier, it stayed a step ahead of settlement, moving west to the tall grass prairies before crossing the Mississippi to colonize the Great Plains. Once there it did calculable damage to the writing of Plains Aboriginal history. After all, who lives upon deserts but wandering beasts and savages? Beneath the mirage was an aboriginal network of agricardos, or agricultural and trading centers, growing enough food to support large populations, and produce tradable surpluses, under-girded by bison protein. Euramericans from Cabeza de Vaca on were drawn to agricardos which helped broker the passages of horses to the Northern Plains and of firearms to the Southwest. While some withstood epidemic disease, the escalation of inter-group violence and environmental degradation due to the adoption of the horse by agricardo groups proved their undoing. Beneath the Great American Desert lies the great Indian agricardo complex, with its history just begun.</p>

This thesis looks at the pueblo theory as it was presented: whether there is anything supporting Rogers' theory, whether a pueblo could have existed in the area, and why the claim has been generally accepted by the archaeological community.

This thesis is the culmination of a graduate research project involving a floristic survey of the lichens of the Spring Mountain National Recreation Area (SMNRA), Humboldt-Toiyabe National Forest, Nevada. The project was based on extensive collections made between 1997 and 2007 as part of an air pollution biomonitoring program and a baseline established by Larry St. Clair (BYU). The Spring Mountains are a sky island mountain range in the Mojave Desert located less than an hour northwest of Las Vegas. A floristic survey of the lichen communities in the Spring Mountains represents a major addition to our understanding of the lichen flora of the Mojave Desert, a poorly studied region in western North America. This thesis also compares the lichen flora of the SMNRA with other lichen floras of the Mojave Desert based on a literature survey of all the lichen studies conducted in the Mojave Desert. The SMNRA species list represents 58% of the 217 species in 68 genera reported for the Mojave Desert. This survey of all reported Mojave lichen species reveals several interesting interactions related to species diversity, substrate, and growth form distribution patterns. These interactions appear to be influenced by two general factors: Microhabitat conditions and available substrates – which are further defined by differences in geological substrates, occurrence and development of woody plant communities, and a combination of environmental factors – elevation, temperature, precipitation, and insolation. Drier and warmer habitats are generally dominated by crustose species with some, mostly smaller, foliose taxa in protected microhabitats usually with shaded or northern exposures. Fruticose species are generally lacking or sparse with smaller thalli when found in hot and dry habitats. All the fruticose species reported from the Mojave Desert sites were rare and had very small thalli. Many foliose and fruticose species, with larger, more complex thalli and thus greater surface area, are more susceptible to higher rates of water loss and therefore occur less frequently in extreme arid locations. The lichen communities in the Mojave Desert respond to sharp contrasts in microhabitat conditions with exposed, lower elevation sites having lower numbers of species along with more drought resistant growth forms – crustose and squamulose species. The Spring Mountains NRA, with high elevation mountains and well developed woody plant communities, accommodates a large variety of microhabitat conditions spread over a complex temperature and moisture gradient. These conditions have resulted in the highest species diversity (124 species in 48 genera) and the greatest number of foliose and corticolous species when compared with all of the other Mojave Desert lichen floras.

Under efterkrigstiden har ett antal operationer med luftmakt genomförts. Dessa krig har haft olika förlopp där vissa operationer har nått relativt enkla framgångar medan andra haft större svårigheter att effektivt uppnå framgång, trots överlägsna resurser. Genom en fallstudie av två moderna luftoperationer, operation Desert Storm i Irak år 1991 och operation Allied Force i Kosovo år 1999, undersöks tre luftmaktsteoretiska variablers betydelse för dessa operationers väg till framgång. Variablerna som undersöks är hämtade ur den moderna luftmaktsteori som John Warden har bidragit till att bilda och vars syfte är att bidra till att förklara hur strategisk förlamning av motståndaren uppkommer. Resultatet av undersökningen visar att systemperspektiv sannolikt bidrar till luftoperativ framgång, däremot kan inte parallell attack visas ha betydelse för att uppnå framgång. Den tredje undersökta variabeln, luftoperativ kontroll, befinns vara betydelsefull som en förutsättning för de övriga två variablernas funktion.

Polar desert environments are limiting in plant available nutrients, mainly nitrogen (N) and phosphorus (P) that severely limit plant growth and establishment. Cryogenic activity regularly patterns the ground into a patchwork of frost boils – sorted circles that are associated with an increase in moisture, fertility and plant cover. Within some frost boils, the accumulation of ice-rich soil at the permafrost table can cause an upward flow of soil organic carbon (SOC) enriched permafrost material into the active layer. These diapiric intrusions are predicted to fuel microbial activity and enrich the horizon in N and P; however, the enrichment of the diapir horizon and accessibility by plants has yet to be studied. The aim of this research was to characterize the N distribution within diapir horizons located in frost boils and the effect of these intrusions on vascular plant N uptake in a polar desert ecosystem of the Canadian High Arctic. Natural abundance and enriched isotope 15N techniques were used to trace the flow of N through the soil-plant system. Surface and diapir horizons contained the highest total C and total N content within frost boils. Natural abundance δ15N analysis indicated that uptake by Salix arctica plants located on frost boils in the absence of a diapir horizon were sourcing N from the surface. However, when diapir nutrients became available, S. arctica plants began sourcing N from the diapir horizon and underlying low SOC sources in the soil, while reducing uptake from the surface. The altered foraging strategy of S. arctica in response to diapir horizon formation was further indicated by significant uptake of atom%15N nutrients that were injected directly into diapir horizons. These findings suggest diapir horizons are enriched in N and accessible by plants roots as an important nutrient source that is instrumental in their survival within frost boils of a polar desert ecosystem in the high arctic.

In A Theory of Justice, John Rawls names two conditions as necessary and sufficient for an agent to have self-respect. I argue that Rawls’s two conditions constitute an inadequate understanding of self-respect. Contrary to Rawls, I argue that self-respect requires moral desert, and that self-respect is a distinct concept from self-esteem.

Thesis (MBA)--Stellenbosch University, 2004 / ENGLISH ABSTRACT: Desert Cool is a South African manufacturing, wholesale, and retail company that markets 4x4 accessories and camping gear through its retail outlets trading as 4x4 Mega World. Desert Cool has sole import rights for well known products, like Engel fridge/freezer, ARB accessories and Old Man Emu suspensions. Desert Cool recently created its own brand name "Sunset Gear" under which it will market various 4x4 accessories and camping gear. Desert Cool has grown fast over the last two years and they are already being seen as the leading 4X4 accessories company in South Africa. Important priorities in the organisation are the development of new products, changes to current products and to satisfy customer needs. Currently these priorities are not being managed properly. Also due to fast growth in terms of sales the organisational structure has not been attended to and has fallen behind. Several projects have delivered poor results due to the wrong approach and poor management of the projects. The goal of this study is to sell the concept of matrix management and organisational structure to the management of Desert Cool, instead of keep on following the conventional functional structure. The study project examines the advantages, disadvantage and characteristics of functional as well as matrix management. It also examines and lists the criteria's on which one can select between the two organisational structures. These criteria have been used in a survey with a questionnaire to obtain top management's views. The survey resulted in the following conclusions: The questionnaire used can be divided into three sections, section 1 is an introduction to matrix management, section 2 is a selecting phase where the respondents need to select between matrix and functional management and the last section is an evaluation of the respondents' responses in the first two sections. The results indicate that the average vote for matrix management in section 1 is 94%, in section 2, 57% and in section 3, 68%. The low percentage in section 2 is not due to a low vote percentage for matrix management (received 84% of the votes), but more due to the level of preference for matrix management. The percentage votes received in section 3 is not too low, but a higher percentage was expected when compared to the 94% in section 1. The 68% also raises a concern when one looks at the results in the functional management section. The results also indicate that the average votes for functional management in section 1 is 6%, in section 2 it is 11% and in section 3 it is 54%. Due to the low score in section 1 a low score in section 2 was expected and for that matter also in section 3, but a fairly high vote came from section 3. The introduction and selecting sections (section 1 and 2) give results that are inline of what were expected, but the evaluation section (section 3) shows a different result. With a closer investigation into this result, it became clear that most of the people could not separate the matrix characteristics from the functional characteristics. This resulted that in some instances high votes were given to both the matrix and the functional characteristic that are opposed to each other. Due to limited knowledge of matrix management amongst management, we need to supply them with more clear info so that they can obtain a better understanding. A better understanding of matrix management might have resulted in a better response in section 3 of the questionnaire. Overall a good result has been obtained. To conclude, Desert Cool cc is growing at a fast rate, but their structure and management style has fallen behind. Matrix management will offer a complete management style as can be seen from the results. The basis has been laid through the survey and matrix management need to be represented in a formal way to all the people of Desert Cool. This document will contribute to understand the advantages, disadvantages, characteristics and the issues of matrix management. It also explains the role of the project manager in this structure. / AFRIKAANSE OPSOMMING: Desert Cool is 'n Suid Afrika gebaseerde maatskappy wat 4 x 4 toebehore en kamptoerusting vervaardig, groothandel en klein handel en bemark dit deur sy kleinhandeltakke, 4 x 4 Megaworld. Desert Cool het alleen invoerregte vir produkte soos Engel vries/yskaste, ARB toebehore en Old Man Emu onderstelle. Desert Cool het onlangs sy eie handelsmerk geskep, naamlik 'Sunset Gear'. Verskeie produkte word onder hierdie handelsmerk bemark. Desert Cool het baie vinnig gegroei oor die laaste twee jaar en word reeds gesien as die leier in die 4 x 4 toebehore mark in Suid-Afrika. Belangrike prioriteite binne die maatskappy is die ontwikkeling van nuwe produkte, verbeteringe aan huidige produkte en om aan kliente se behoeftes te voldoen. Huidiglik word hierdie prioriteite nie behoorlik gebestuur nie. As gevolg van die hoe groei tempo in verkope en die groot hoeveelheid aandag wat daaraan gegee is, het die ontwikkeling van die organisasie struktuur agterwee gebly. 'n Hele paar projekte het swak resultate opgelewer weens die verkeerde benadering en swak bestuur daarvan. Die doel van hierdie studie is om die konsep van matriksbestuur en -organisasie struktuur aan die bestuur van Desert Cool te verkoop, en om af te sien van die huidige funksionele organisasie struktuur. Die studieprojek ondersoek die voordele, nadele en kenmerke van funksionele- en matriksbestuur. Dit ondersoek ook die kriteria's wat gebruik kan word om te kies tussen die twee organisasie strukture. Hierdie kriteria's word dan gebruik in 'n ondersoek, in die vorm van 'n vraelys, om die opinie van die hoofbestuur te verkry. Die vraelys kan in drie afdelings opgedeel word, afdeling 1 kan beskou word as 'n inleiding tot matriksbestuur, afdeling 2 is 'n keuse fase waar die respondente 'n keuse moet maak tussen funksionele- en matriksbestuur en die laaste afdeling dien as 'n evaluasie van die respondent se antwoorde in afdeling 1 en 2. Die resultate dui daarop dat die gemiddelde stem vir matriksbestuur in die afdeling 1, 94% is, in afdeling 2, 57% is en in afdeling 3, 68% is. Die lae persentasie gemiddelde in afdeling 2, is nie as gevolg van 'n lae stem persentasie vir matriksbestuur nie (verkry 84% van stemme), maar meer as gevolg van die vlak van voorkeur vir matriksbestuur. Die persentasie stemme ontvang in afdeling 3 is nie te laag nie, maar 'n hoër persentasie is verwag wanneer daar gekyk word na die 94% wat in afdeling 1 behaal is. Die 68% is ook kommerwekend wanneer daar gekyk word na die persentasie stemme wat funksionele bestuurs in afdeling 3 (gemiddelde van 54%) behaal het. Die resultate dui dat die gemiddelde stem vir funksionele bestuur in afdeling 1, 6% is, vir afdeling 2, 11 % is en vir afdeling 3, 54% is. As gevolg van die lae telling in afdeling 1, is daar 'n lae telling in afdelings 2 en 3 verwag, maar 'n redelike hoë persentasie stemme is behaal vir funksionele bestuur in afdeling 3. Afdeling 1 (inleding) en afdeling 2 (selekteuring) lewer resultate in Iyn met wat verwag is, maar afdeling 3 (evalueering) het 'n meer teenstrydige resultaat gelewer, as dit wat verwag is. Met nadere ondersoek op die resultaat, het dit aan die lig gekom dat respondente nie kon onderskei tussen die matriks en die funksionele kenmerke van die strukture nie. Dit het daartoe gelei dat hoë stemme in sommige gevalle aan beide die teenstaande kenmerke gegee is. Die beperkte kennis wat hoofbestuur het van matrikbestuur, het bygedra tot die swak resultaat in afdeling 3. Dit is dus noodsaaklik dat hulle eers meer breedvoerig ingelig word aangaande matriksbestuur, sodat hulle dit better kan verstaan, voordat 'n evaluasie van so 'n aard gedoen word. Indien hulle matriksbestuur beter verstaan het kon dit tot 'n beter resultaat in afdeling 3 gelei het. Oor die algemeen is goeie resultate verkry. Om mee af te sluit, Desert Cool groei teen 'n hoe tempo, maar die organisasiestruktuur en bestuurstyl het agterwee gebly. Die resulate dui daarop dat matriksbestuur die mees aangewese bestuurstyl vir Desert Cool is. Die basis is gelê deur die ondersoek en nou moet matriksbestuur op 'n formele manier aan almal oorgedra word. Hierdie dokument sal bydra om die voordele, nadele en kenmerke van matriksbestuur beter te verstaan. Dit verduidelik ook die rol van die projekbestuurder in die struktuur.

3 pp. / Revised / The most effective weed control practice in alfalfa is maintaining a healthy crop and dense stand. Cultural practices that promote a vigorous stand can reduce the need for chemical weed control. Cultural practices that promote a healthy stand reduce the need for chemical weed control, but herbicides are sometimes necessary even in well-managed alfalfa.