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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Alpine plant-ant interactions /

Puterbaugh, Mary Norris, January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
112

Alpine plant-ant interactions

Puterbaugh, Mary Norris, January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
113

Vegetationsentwicklung auf Skipistenplanierungen in der alpinen Stufe bei Davos = Development of vegetation on levelled ski runs in the alpine zone near Davos /

Meisterhans, Edwin. Meisterhans, Edwin. January 1988 (has links)
Diss. Nr. 8462 Naturwiss. ETH Zürich. / siehe auch: Vegetationsentwicklung auf Skipistenplanierungen in der alpinen Stufe bei Davos. Bibliogr.: p. 144-150.
114

Crescimento relativo dos cortes e tecidos da carcaça de caprinos de cinco grupos raciais terminados em pasto ou confinamento /

Lourençon, Raquel Vasconcelos, 1981. January 2011 (has links)
Orientador: Heraldo César Gonçalves / Banca: Simone Fernandes / Banca: Mauro Sartori Bueno / Resumo: Este trabalho foi realizado com o objetivo de avaliar o crescimento relativo dos cortes comerciais e dos tecidos da carcaça de caprinos. Foram utilizados 78 cabritos, machos e fêmeas, de cinco grupos raciais: Alpino; 1/2 Boer + 1/2 Alpino (1/2 BA); 1/2 Anglo Nubiano + 1/2 Alpino (1/2 ANA); 3/4 Boer + 1/4 Alpino (3/4 BA); e ½ Anglo Nubiano + ¼ Boer + ¼ Alpino (TC). Os grupos foram distribuídos em dois sistemas de terminação, pasto (ST1) e confinamento (ST2). Os cabritos foram abatidos em média aos 22,07 kg de peso vivo e 128,4 ± 7,9 dias. O peso médio das meias carcaças foi de 5,09 kg. Para determinação do crescimento alométrico foi utilizada a equação exponencial Y = aXb. O cruzamento com a raça Anglo Nubiana proporcionou o crescimento precoce da perna em relação ao peso da meia carcaça (PMC). O lombo cresceu tardiamente nos animais Alpinos e ½ ANA. Nos animais do grupo TC as costelas apresentaram crescimento tardio. Os cruzamentos não influenciaram no desenvolvimento do pescoço. A paleta foi considerada precoce nos animais ½ BA e TC. O tecido muscular, em relação ao PMC, apresentou crescimento precoce no grupo ½ BA. No ST1, a paleta cresceu precocemente, enquanto no ST2 este crescimento foi isogônico. O tecido adiposo dos animais do ST1 foi depositado tardiamente. As fêmeas apresentaram crescimento precoce de perna e tecido muscular, que nos machos foi considerado intermediário. O crescimento dos caprinos é influenciado pelos cruzamentos raciais, sistema de terminação e sexo / Abstract: This work was conducted with the objective of evaluate the relative growth of carcass cuts and tissues of goats. Seventy-eight male and female kids from five racial groups were used: Alpine; ½ Boer + ½ Alpine (½ BA); ½ Nubian + ½ Alpine (½ ANA); ¾ Boer + ¼ Alpine (¾ BA); and ½ Nubian + ¼ Boer + ¼ Alpine (TC); distributed in two finishing systems, pasture (FS1) and feedlot (FS2). The kids were slaughtered at an average of 22.07 kg of live weight and 128.4 ± 7.9 days. The average weight of half carcasses was 5.09 kg. To determine the allometric growth the exponential equation was used Y= aXb. The crossing with the Anglo Nubian provided the early growth of the leg in relation to the half carcass weight. The loin grew late in the Alpine animals and ½ the ANA. In animals from group TC ribs grew late. The crossings did not influence the development of the neck. The palette was considered earlier in kids ½ BA and TC. Muscle tissue in relation to the half carcass, grew early in the group ½ BA. In FS1, the palette grew early, while this growth was intermediate in FS2. The fat tissue of animals in FS1 had a late growth. The females showed early growth of leg and muscle tissue, while in males was considered intermediate. The growth of goats is influenced by the crossings, sex and finishing system / Mestre
115

The Plateau Pika: A Keystone Engineer on the Tibetan Plateau

January 2010 (has links)
abstract: The highly-social plateau pika (Lagomorpha: Ochotona curzoniae) excavates vast burrow complexes in alpine meadows on the Tibetan Plateau. Colonies of over 300 individuals/ha have been reported. As an ecosystem engineer, their burrowing may positively impact ecosystem health by increasing plant species diversity, enhancing soil mixing, and boosting water infiltration. However, pikas are commonly regarded as pests, and are heavily poisoned throughout their range. The underlying assumption of eradication programs is that eliminating pikas will improve rangeland quality and decrease soil erosion. This dissertation explores the link between plateau pikas and the alpine meadow ecosystem in Qinghai Province, PRC. This research uses both comparative field studies and theoretical modeling to clarify the role of pika disturbance. Specifically, these studies quantify the impact of pikas on nutrient cycling (via nutrient concentrations of vegetation and soil), hydrology (via water infiltration), local landscape properties (via spatial pattern description), and vascular plant communities (via species richness and composition). The competitive relationship between livestock and pikas is examined with a mathematical model. Results of this research indicate that pika colonies have both local and community level effects on water infiltration and plant species richness. A major contribution of pika disturbance is increased spatial heterogeneity, which likely underlies differences in the plant community. These findings suggest that the positive impact of plateau pikas on rangeland resources has been undervalued. In concurrence with other studies, this work concludes that plateau pikas provide valuable ecosystem services on the Tibetan Plateau. / Dissertation/Thesis / Ph.D. Biology 2010
116

Offpistskidåkning i svenska fjällen : - Om topptursutrustning och riskbeteende

Åkesson, Anna January 2018 (has links)
The purpose of this study was to determine whether ski tourers in the Swedish mountains have enough knowledge and experience to perform the activity safely. Adventure oriented activities that demands equipment has over the last years increased among outdoor practitioners in Sweden. Because of the growth, ski touring equipment have had a rapid development and made the activity more accessible. In the northern parts of Sweden a survey- and a field study, were examine risk behavior, avalanche equipment and techbindings. The results shows that ski touring has increased over the last years and that the activity is mainly performed by young men that are experienced downhill skiers. According to the result men seems to have a higher risk acceptance and many off-piste skiers are prepared to take risks to get good skiing/ski touring. Nearly everyone from the study are carrying avalanche equipment, but it seems like some are not sufficiently prepared in case of an accident. The results also indicates that some ski tourers dis-trust the retention function of techbindings and some manually lock out the release mechanism of the binding exposing themselves to a high risk of lower leg injury.
117

Vývoj německých alpských spolků v Českých zemích do roku 1938 / Development of German Alpine Clubs in Czech Lands until 1938

Chaloupská, Pavlína January 2014 (has links)
Mgr. Pavlína Chaloupská, abstrakt disertační práce Abstract: The thesis analyzes activities of the most important German Alpine clubs operating in the Czech Lands and interwar Czechoslovakia since their establishment until 1938. The history of alpine clubs is explained, and the organization of DuÖAV (Deutscher und Österreichischer Alpenverein, German and Austrian Alpine Association) is analysed, on the basis of general and specific introductory information related to the alpinism in the late 19th century. The thesis is divided according to geographical location of the constituent sections. For each section of DuÖAV, the circumstances of its establishment are monitored, the sphere of its activity is defined, the internal organization is described, and the economic functioning is analyzed. The activities of Alpine clubs in Bohemia and Alps are charted in detail, and based on the research it was discovered that the most important activity of the Alpine clubs was the construction of the Alpine huts, owned by German clubs from Bohemia. Among other activities there were organization of guiding and rescue operations, giving lectures, balls and excursions in their locality. Two chapters are devoted to the most important personalities of the German alpinism in the Czech lands: Johann Stüdl and Rudolf Kauschka.
118

Evolution de la niche climatique et de la distribution géographique des espèces végétales alpines / Evolution of climatic niches and geographic distributions in alpine plants

Boucher, Florian 29 November 2013 (has links)
La niche climatique des espèces joue un rôle important dans la distribution spatiale de la biodiversité mais la manière dont les niches climatiques évoluent reste encore peu connue. Ce travail vise à révéler la manière dont les niches climatiques évoluent en général, et plus précisément à déterminer comment certaines plantes se sont adaptées aux environnements alpins. En étudiant de nombreux groupes de plantes, de poissons, de mammifères et d'oiseaux, nous avons montré que les niches climatiques évoluent le plus souvent par à-coups et non pas de manière graduelle. Les niches climatiques restent en effet stables pendant des périodes de plusieurs millions d'années puis évoluent de manière extrêmement rapide avant de se stabiliser à nouveau dans une autre gamme de climat. Des simulations ont permis de montrer que les phases de relative stabilité n'étaient pas forcément causées par une sélection stabilisante sur les niches climatiques mais pouvaient également résulter de la présence de barrières géographiques qui empêchent les espèces d'expérimenter de nouveaux climats. L'étude de l'histoire des plantes du genre Androsace a révélé que les changements rapides de niches correspondaient au contraire à l'apparition de nouveaux traits, comme la forme de vie en coussin. Ce travail montre que de nombreux facteurs influencent l'évolution des niches climatiques et souligne la nécessité de tous les étudier ensemble. / Species' climatic niches play an important role in the spatial distribution of biodiversity but the way climatic niches evolve remains poorly known. This works aims at determining the general mode of evolution of climatic niches, and more precisely at revealing how some plants have adapted to alpine environments. The study of many groups of plants, fishes, mammals and birds has shown that climatic niches usually evolve by fits and starts but not gradually. Climatic niches indeed remain stable over million years before evoving extremely quickly and stabilizing again in a new range of climates. Simulations have shown that these phases of relative stability need not be caused by stabilizing selection but can also be caused by geographic barriers that impede species from experiencing new climates. The study of the history of plants of the genus Androsace has revealed that rapid niche shifts on the contrary resulted from the appearing of novel traits, like the cushion life form. This work shows that numerous factors contribute to the evolution of climatic niches and emphasizes the necessity to study them together.
119

Etude des sources et de la dynamique atmosphérique de polluants organiques particulaires en vallées alpines : apport de nouveaux traceurs organiques aux modèles récepteurs / Study of sources and atmospheric dynamics of particulate organic pollutants in Alpine valleys : contribution of new organic tracers for receptor modelling applications

Golly, Benjamin 15 October 2014 (has links)
Récemment, la qualité de l'air dans la région Rhône-Alpes est devenue un sujet sensible depuis sa mise en demeure par l'Union Européenne pour non respect des normes en vigueurs concernant les taux de particules fines (PM). Effectivement, certaines zones géographiques de la région connaissent de nombreux dépassements en PM10, particulièrement dans les vallées alpines durant la période hivernale. Ces dépassements en particules sont aussi accompagnés de fortes concentrations en composés organiques comme les hydrocarbures aromatiques polycycliques (HAP) constituants ces PM. Un accroissement des connaissances sur les sources de pollution atmosphérique particulaire et leurs dynamiques au sein des vallées alpines est alors nécessaire, ceci afin d'améliorer la mise en place des politiques de diminution des émissions grâce à une meilleure connaissance de l'influence des différentes sources au niveau régional. Ces travaux de thèse sont axés autour des émissions des sources industrielles encore mal connues et plus particulièrement l'industrie du carbone très présente dans les bassins industriels de ces fonds de vallées. Les approches classiques par les éléments métalliques n'étant pas spécifiques, l'exploration de la fraction organique a permis de proposer un profil chimique organique complet et d'avancer le benzo(b)naphtho(2,1-d)thiophène (BNT(2,1)), composé particulaire majoritaire de la famille des Hydrocarbures Aromatiques Polycycliques soufrés (HAPS) comme traceur de cette source. Ce composé a été détecté et quantifié sur plusieurs sites en proximité d'activités industrielles confirmant ainsi sa source potentielle. De plus le profil industriel a été introduit comme profil « source » afin d'évaluer sa robustesse dans les méthodologies de type modèle récepteur de bilan de masse comme le « Chemical Mass Balance » (CMB) et statistique comme la « Positive Matrix Factorization » (PMF). Les résultats ont confirmé l'intérêt de l'ajout des composés organiques à ces méthodologies. Ainsi, le profil industriel et les composés organiques HAPS ont permis de mieux tracer la source appelée génériquement « industrie du carbone » (combustions de charbon, de coke et de matériaux graphitiques) dans les vallées alpines mais aussi sur différents sites urbains français. En parallèle, un modèle de régression non linéaire multivarié (MRNL) a été développé pour la quantification des sources de HAP, basé sur l'utilisation de traceurs spécifiques de source (lévoglucosan, hopanes….) et de données météorologiques (gradient thermique). Son application a été validée sur un ensemble de sites alpins des vallées de l'Arve et de la Tarentaise. Un couplage entre ce modèle et les données de mesures optiques du carbone suie (BC) par aéthalomètre, a permis de proposer une solution aux mauvais résultats de corrélation entre les HAP mesurés et modélisés par le modèle MRNL sur le site de la vallée de la Maurienne. Ces faibles corrélations peuvent être liées à une mauvaise représentativité des composés organiques utilisés à tracer correctement les sources d'émission sur certains sites.Enfin, l'inter-comparaison de ces méthodologies pour la détermination des sources de HAP et plus particulièrement de la source industrielle permet de valider cette méthodologie dans une perspective opérationnelle de suivi des sources de HAP sur ces différents sites. Ces travaux réalisés au cours de cette thèse mettent en évidence l'intérêt de la caractérisation de la fraction organique des PM et les biais qui peuvent exister sur l'utilisation des composés organiques pour l'étude des sources d'émissions. Des alternatives y sont proposées afin de soulever ces ambiguïtés et d'améliorer l'étude des sources de HAP par les modèles récepteurs. / Recently, Air quality has become a sensitive topic for Rhône-Alpes region due to the formal notice which was addressed by the European Commission for non-compliance with legislation in force. Indeed, certain geographic areas in the region present a lot of overruns in PM10, especially in Alpine valleys during winter. These overruns particles are also accompanied by high concentrations of organic compounds such as polycyclic aromatic hydrocarbons (PAHs), which constitute these PMs. An increase in khowledge about the sources of particulate air pollution and their dynamics in Alpine valleys is necessary, in order to improve the implementation of policies to reduce emissions through better knowledge of the influence of different sources at regional level. This thesis is focused around emissions from industrial sources still poorly known and particularly of the carbon industry highly present in these industrial areas of the valley bottoms. Traditional approaches by metallic elements being not specific, exploration of the organic fraction allowed to propose a complete organic chemical profile. In addition they led us to evidence the benzo(b)naphtho(2,1-d)thiophene (BNT(2,1)), the most abundant particulate compound of the family of sulfur-containing polycyclic aromatic hydrocarbons (PASHs), as a tracer of this source. This compound was detected and quantified on multiple sites in near industrial activities confirming its potential source. In addition the industrial profile was introduced as profile “source” in order to assess its robustness in methodologies of receptor model like the “Chemical Mass Balance “(CMB) and the “Positive Matrix Factorization” (PMF). The results confirmed the interest of the addition of organic compounds to these methodologies. Thus, the industrial profile and the PASHs compounds have allowed to better trace the source usually called “carbon industry” (coal, coke and graphite materials combustions) in the Alpine valleys but also in different French urban sites. In parallel, a non linear regression model (NLRM) was developed to PAH source apportionment, based on the use of specific molecular markers (levoglucosan, hopanes…) and of meteorological data (altitudinal temperature lapse rate). Its implementation has been validated on a set of sites of the Alpine valleys of Arve and Tarentaise. Coupling between this model and the optical measurements of black carbon (BC) by aethalometer, allowed to propose a solution to the poor performance of correlation between PAHs measured and modeled by NLRM model on this site of the Maurienne valley. These low correlations may be related to poor representativeness of organic compounds used to correctly trace the emission sources at some sites. Finally, the inter-comparison of these methodologies for the determination of PAH sources and especially of industrial source allows to validate this methodology in an operational perspective of monitoring of PAH levels on these sites. The work performed during this thesis highlights the interest of the characterizatin of the organic fraction of PM and the biases that may exist on the use of organic compounds for the study of the emission sources. Some alternatives are suggested to clarify ambiguities and improve the source apportionment of PAHs by receptor models.
120

Produção e composição do leite de cabras alpinas submetidas ao transporte, à mudança de local de ordenha e à administração de ACTH

Canaes, Taissa de Souza [UNESP] 28 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-28Bitstream added on 2014-06-13T19:18:51Z : No. of bitstreams: 1 canaes_ts_me_jabo.pdf: 627539 bytes, checksum: a19cf142d9cad8b982065ff380586a32 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O transporte de animais é um manejo intrínseco à atividade agropecuária. Com o objetivo de estudar o efeito do transporte, a mudança de local de ordenha e a administração de ACTH sobre a produção e composição do leite, foram utilizadas doze cabras Alpinas pluríparas no final da lactação. O trabalho foi realizado em três experimentos: 1) transporte e mudança de local de ordenha com o objetivo de estudar seus efeitos sobre a produção e composição do leite; 2) transporte dos animais e retorno ao mesmo local para estudar seus efeitos sobre a produção e composição do leite e o comportamento; 3) administração de ACTH com a finalidade de estudar os efeitos do aumento do nível de cortisol sobre a produção de leite. Nas três etapas experimentais, foram colhidas amostras de sangue para dosagens hormonais (cortisol) e enzimáticas (glicose, proteína total e triglicerídeos) no plasma antes (-10 min) e após (O, 10 e 120 min) o transporte, nas semanas subseqüentes após a ordenha (O e 1 ° min); e anterior (-10 min) e após (O, 10, 30, 60, 120 e 180 min) a administração de ACTH. Semanalmente foram mensuradas a produção e composição do leite e no primeiro experimento foram mensurados volumes do leite residual após administração de ocitocina. Os resultados demonstraram níveis maiores (P<0,05) de cortisol e glicose após o transporte e mudança de local de ordenha, e após administração de ACTH. A produção de leite foi significativamente menor (P<O,05) para o experimento 1 e 3, não ocorrendo alteração após o segundo experimento. Não foram observadas alterações (P>0,05) na composição do leite durante o experimento 1 e 2, exceto para o parâmetro gordura (P<0,05)... / Animal transport is an inherent handling in combined agriculture activity. The aim of this study was to evaluate the effect of transportation and reallocation, and ACTH administration on milk production and composition. Twelve Alpine goats at the end of lactation were used. The work was accomplished in three experiments: 1) transportation and reallocation of the animais to study the effects on production and composition of milk; 2) transportation of the animais and its return to the same site to study the effect on production and composition of milk and animais behavior; 3) administration of ACTH with the purpose of studying agent's effects stressor on the physiologic variables and on milk production. The physiologic variables were analyzed in three experimental stages. Blood samples were taken for hormonal dosages (cortisol) and enzymatic (total protein glucose and triglycerides) in plasma before (-10 min) and after (O, 10 and 120 min) transportation and/or milking in subsequent weeks after milking (O and 10 min); prior (-10 min) and after (O, 10, 30, 60, 120 and 180 min) ACTH administration. Production and composition of milk were measured weekly. In the first stage, volumes of the residual milk after oxytocin administration were monitored. The results demonstrated larger levels (P<0.05) of cortisol and glucose after transportation and reallocation, and ACTH administration. Milk production was significantly lower (P<0.05) after experiment 1 and 3; no change was observed (P>0.05) after the second experimental stage. Changes in milk composition were not observed (P>0.05) except for fat (P<0.05). Behavioral analysis did not reveal any alteration (P>0.05) in the transport experiment...(Complete abstract, click electronic address below)

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