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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.
511

PRAGMATISM AND THE POLITICS OF REWILDING NATURE: THE CASE OF GRIZZLY BEAR REINTRODUCTION IN IDAHO

Hintz, John G. 01 January 2005 (has links)
In 1975, the US Fish and Wildlife Service listed the grizzly bear as a threatened species under the Endangered Species Act. Following the listing, a recovery plan was drafted in which the Bitterroot Ecosystem of central Idaho and extreme western Montana was one of six proposed grizzly bear recovery areas. It was the only one of the six, however, which did not contain a resident population of grizzlies. The Fish and Wildlife Service eventually accepted a proposal submitted by a coalition of environmental and timber industry groups. The coalition proposed to reestablish a population of grizzlies in the Bitterroot by translocating 25 bears over five years from existing populations in the US and Canada. The proposal, however, included significant concessions, including reduced protection for the reintroduced grizzlies and management of the grizzly population by a Citizen Management Committee. A large contingent of regional and national environmental groups quickly rose up in vociferous objection to the proposal exposing a significant rift within the environmental movement. These environmentalists objected to the very idea of Citizen Management and also claimed that the proposed recovery area was too small to ensure recovery. Drawing on interviews and document analyses, this dissertation employs an environmental pragmatist approach to examine the intra-environmentalist disputes that flared up throughout the Bitterroot grizzly recovery debates. The dissertation focuses on the relationship between environmental ideologies, science, and conservation advocacy, with an eye toward examining how environmentalists crafted and defended rival proposals for grizzly recovery. Through this interpretive lens, the dissertation aims to explain the existence and persistence of this intra-environmentalism rift as well as explore its ramifications for environmentalism in the region. While no wholly unified environmental movement can ever be possible or is even necessarily desirable unwavering commitments to unreachable ideals on the part of many environmentalists are hindering the growth, flexibility and efficacy of conservation in the region. The main contribution of this dissertation will be to provide an empirical case study that defends the environmental pragmatist assertion that hostile and unnecessary divisiveness within the environmental movement ultimately obstructs the development of a more successful environmentalism.
512

Entreprenörers förmåga att nå sin målmarknad

Kandlan, Sandrin, Nilsson, Christine January 2013 (has links)
The tourism industry is a young industry in Sweden but important for the economy and a large part of the field is mountain tourism. Marketing a place is called destination marketing, which has become a huge phenomenon and an important part of efforts for promotion in the tourism industry. The entrepreneurs in the tourism industry are an important part, as these are a big part of the destination. Their marketing and communication becomes a force to reckon with in order to attract tourists to the area. The purpose of this study is to examine how entrepreneurs through destination marketing reach their target market and with the intention to identify marketing channels that the entrepreneur uses. To achieve this, two questions will be answered: How can entrepreneurs attract customers through destination marketing? Which marketing channels do business owners use to reach out to their target market in the tourism industry? The theories used in this study are destination marketing, internet marketing, services marketing, and entrepreneurs as business owners. This study’s methodology consists of four semi-structured interviews with companies operating in Åre, which is a destination where tourists can visit the mountain all year out. Also a content analysis has been done where an observation was made looking at the company’s internet marketing. The conclusion is that the entrepreneurs through collaboration can increase the demand on the destination and reach out to more tourists. The marketing channels that was used the most is digital communication, more specifically, social media like Facebook and Instagram. Also search engine optimization to get higher traffic to the corporate website is used.
513

Park Cerro de las Tres Cruces

Magan, Jose Luis January 1993 (has links)
The high cost of land generates an inner growth in the cities in South America. In Cali, Colombia this growth has created a dense landscape with few open areas appropriated for the outdoor recreation of Cali's inhabitants.Calehos prefer to develop projects on flat surfaces. However, every day more residential projects are being developed in the foot of the hills that surround Cali, leaving the areas undeveloped in the upper part of the mountains.A landscape architect can preserve these green areas for the enjoyment of the Calehos, providing at the same time a solution for the present problems of erosion and landscape destruction. / Department of Landscape Architecture
514

Radial-growth response of mountain hemlock (Tsuga mertensiana) trees to climate variations along a longitudinal transect, northwestern British Columbia, Canada

Penrose, Kelly-Anne 10 June 2008 (has links)
This research was initiated to develop an understanding of the differential radial-growth response of mature mountain hemlock (Tsuga mertensiana) trees located along a line of latitude in northwestern British Columbia. Increment core samples were collected from mountain hemlock stands located at five high-elevation sites between the Queen Charlotte Islands and Smithers. Tree ring-width index chronologies were compared to historical precipitation and air temperature data from four climate stations, as well as the El Nino Southern Oscillation and the Pacific Decadal Oscillation. No two mountain hemlock stands had the same growth response to monthly air temperature and precipitation, indicating that the trees are responding to site-specific limiting factors. The response to El Nino Southern Oscillation events was consistent along the transect, while the response to Pacific Decadal Oscillation phase changes was greatest at coastal sites and decreased towards the interior.
515

Lietuvos pilkųjų (Lepus europaeus) ir Baltųjų (Lepus timidus) kiškių kaukolių morfologinė analizė / Skulls morphological analysis of European hare (Lepus europaeus) and Mountain hare (Lepus timidus) in Lithuania

Kriščiūnaitė, Asta 05 March 2014 (has links)
Darbo tikslas: išmatuoti Lietuvoje paplitusių pilkųjų ir baltųjų kiškių kaukoles ir nustatyti šių kiškių kaukolių morfologinius tarprūšinius skirtumus. Tyrimas buvo atliekamas Kauno Tado Ivanausko zoologijos muziejuje, naudojant šiame muziejuje esančią kiškių kaukolių kolekciją. Osteometrinei analizei naudota 29 L. europaeus, 21 L. timidus kaukolės. Makroskopinei palyginamajai analizei naudota 68 L. europaeus, 24 L. timidus kaukolės. Osteometrinei analizei atlikti buvo pasirinkti 31 matavimas. 21 matavimas atliktas remiantis F. Palacios metodika, modifikuota F. Riga ir kt. (2001 m.), 10 matavimų atlikti pagal A. von den Driesch (1976) metodiką. Matavimai atlikti elektroniniu slankmačiu 0,01 mm tikslumu. Makroskopinė palyginamoji analizė buvo atliekama remiantis F. Palacios 1998 m. metodika. Tyrimo metu tarp rūšių nustatyta 15 statistiškai patikimų matmenų (P<0,05) ir 8 makrsokopinės anatomijos tarprūšiniai skirtumai. Išvados: pilkųjų kiškių veidinė dalis yra ilgesnė ir platesnė už baltųjų kiškių. Pilkųjų kiškių kiaušo dalis yra aukštesnė už baltųjų kiškių, tačiau baltiesiems kiškiams būdinga platesnė priekinė kiaušo dalis. Bendras kaukolės ilgis tarp rūšių nesiskiria, tačiau baltųjų kiškių kaukolės yra platesnės. Atlikus tarprūšinę pilkųjų ir baltųjų kiškių kaukolių ir apatinių žandikaulių osteologinę analizę, nustatyti 7 kaukolės ir 1 apatinio žandikaulio skirtumas. / Aim: To measure the spread of European and Mountain rabbit skulls in Lithuania as well as determine the morphological differences and variations of the skulls between the species. The study was conducted at Tadas Ivanauskas Zoology Museum in Kaunas, using the collection of the rabbit skulls presented there. In terms of the study, the 29 L. europaeus, 21 L. timidus skulls were used for Osteometric analysis while 68 L. europaeus, 24 L. timidus skulls were used for macroscopic comparative analysis. During the Osteometric investigation, thirty one measurement was performed in total, in which twenty one of them was based on F. Palacios methodology (modified F.Riga et al., (2001)) while other ten were based on A. von den Driesch (1976) methodology. Measurements were performed using electronic caliper with 0.01mm accuracy. Macroscopic comparative analysis was performed with reference to F. Palacios, (1998) methodology. As a result, fifteen statistically relevant dimensions (P<0,05) were discovered along with eight macroscopic anatomical variations between the species. Conclusions: The facial part of the European rabbit skull is longer and wider when compared to the Mountain rabbit skull. In addition, the neurocranium of the European rabbit skull is higher. However, Mountain rabbits typically have wider frontal area of the neurocranium. Overall length of the skull remains the same between the species, nevertheless, white rabbits were discovered to have generally wider skulls. The... [to full text]
516

Development of Bio-based Phenol Formaldehyde Resol Resins Using Mountain Pine Beetle Infested Lodgepole Pine Barks

Zhao, Yong 13 August 2013 (has links)
Phenol formaldehyde (PF) resol resins have long been used widely as wood adhesives due to their excellent bonding performance, water resistance and durability. With the growing concern for fossil fuel depletion and climate change, there is a strong interest in exploring renewable biomass materials as substitutes for petroleum-based feedstock. Bark, rich in phenolic compounds, has demonstrated potential to partially substitute phenol in synthesizing bio-based PF resins. In this study, acid-catalyzed phenol liquefaction and alkaline extraction were used to convert mountain pine beetle (MPB; Dendroctonus ponderosae) infested lodgepole pine (Pinus contorta) barks to phenol substitutes, liquefied bark and bark extractives. Two types of bio-based phenol formaldehyde (PF) resol resins, namely liquefied bark-PF resin and bark extractive-PF resins, were then synthesized and characterized. It was found that acid-catalyzed phenol liquefaction and alkaline extraction were effective conversion methods to obtain phenol substitute with the maximum yield of 85% and 68%, respectively. The bio-based PF resol resins had higher molecular weights, higher polydispersity indices, shorter gel times, and faster curing rates than the lab synthesized control PF resin without the bark components. Based on the lap-shear tests, the bio-based PF resol resins exhibited comparable wet and dry bonding strength to lab PF resin and commercial PF resin. The post-curing thermal stability of the bio-based PF resins was similar to the lab control PF resin. The liquid-state 13C nuclear magnetic resonance (NMR) study revealed significant influences on the resin structures by the inclusion of the bark components. Methylene ether bridges, which were absent in the lab PF resin, were found in the bio-based PF resins. The bark components favored the formation of para-ortho methylene linkages in the bio-based bark extractive-PF resins. The liquefied bark-PF resin showed a higher ratio of para-para/ortho-para methylene link (-CH2-), a higher unsubstituted/substituted hydrogen (-H/-CH2OH) ratio and a higher methylol/methylene (-CH2OH/-CH2-) ratio than the bark extractive-PF resin. Both tannin components of bark alkaline extractives and phenolated barks contributed to the acceleration of the curing rate of the bio-based resins. This research demonstrated the promise of the bio-based PF resins containing either bark alkaline extractives or liquefied barks as environmentally friendly alternatives to PF adhesives derived solely from fossil fuel based phenol and proposed a novel higher value-added application of the largely available barks from the mountain pine beetle-infested lodgepole pine trees.
517

Development of Bio-based Phenol Formaldehyde Resol Resins Using Mountain Pine Beetle Infested Lodgepole Pine Barks

Zhao, Yong 13 August 2013 (has links)
Phenol formaldehyde (PF) resol resins have long been used widely as wood adhesives due to their excellent bonding performance, water resistance and durability. With the growing concern for fossil fuel depletion and climate change, there is a strong interest in exploring renewable biomass materials as substitutes for petroleum-based feedstock. Bark, rich in phenolic compounds, has demonstrated potential to partially substitute phenol in synthesizing bio-based PF resins. In this study, acid-catalyzed phenol liquefaction and alkaline extraction were used to convert mountain pine beetle (MPB; Dendroctonus ponderosae) infested lodgepole pine (Pinus contorta) barks to phenol substitutes, liquefied bark and bark extractives. Two types of bio-based phenol formaldehyde (PF) resol resins, namely liquefied bark-PF resin and bark extractive-PF resins, were then synthesized and characterized. It was found that acid-catalyzed phenol liquefaction and alkaline extraction were effective conversion methods to obtain phenol substitute with the maximum yield of 85% and 68%, respectively. The bio-based PF resol resins had higher molecular weights, higher polydispersity indices, shorter gel times, and faster curing rates than the lab synthesized control PF resin without the bark components. Based on the lap-shear tests, the bio-based PF resol resins exhibited comparable wet and dry bonding strength to lab PF resin and commercial PF resin. The post-curing thermal stability of the bio-based PF resins was similar to the lab control PF resin. The liquid-state 13C nuclear magnetic resonance (NMR) study revealed significant influences on the resin structures by the inclusion of the bark components. Methylene ether bridges, which were absent in the lab PF resin, were found in the bio-based PF resins. The bark components favored the formation of para-ortho methylene linkages in the bio-based bark extractive-PF resins. The liquefied bark-PF resin showed a higher ratio of para-para/ortho-para methylene link (-CH2-), a higher unsubstituted/substituted hydrogen (-H/-CH2OH) ratio and a higher methylol/methylene (-CH2OH/-CH2-) ratio than the bark extractive-PF resin. Both tannin components of bark alkaline extractives and phenolated barks contributed to the acceleration of the curing rate of the bio-based resins. This research demonstrated the promise of the bio-based PF resins containing either bark alkaline extractives or liquefied barks as environmentally friendly alternatives to PF adhesives derived solely from fossil fuel based phenol and proposed a novel higher value-added application of the largely available barks from the mountain pine beetle-infested lodgepole pine trees.
518

Induced monoterpene responses in jack pine: defence against jack pine budworm and a fungal associate of the mountain pine beetle

Colgan, Lindsay Jessica 11 1900 (has links)
My thesis research investigated monoterpene responses in jack pine (Pinus banksiana Lamb.) to different agents to better understand how these responses may influence the spread of the mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) in the boreal forest. The results support that monoterpenes are inducible responses in jack pine. In the first study, methyl jasmonate application elicited the greatest response in juvenile and mature trees suggesting that jasmonic acid plays a role in jack pine defence responses. In the cross-induction study, I found evidence of an increase in resistance to Grosmannia clavigera with prior jack pine budworm defoliation (Choristoneura pinus pinus Freeman; JPBW). In contrast, needle monoterpenes greatly increased after G. clavigera inoculation and continued to increase during JPBW defoliation; however, JPBW increased its feeding rate to compensate for a change in host quality. Overall, monoterpene induction in jack pine depended on the agent(s) involved and their order. The systemic responses that were observed may have implications for MPB spread in the boreal forest. / Forest Biology and Managment
519

Studies of the germination of seven Australian alpine and subalpine shrub species

MacPhee, Elizabeth Unknown Date (has links) (PDF)
Seeds of seven alpine and subalpine Australian shrub species (Acacia alpina,A. obliquinervia, Bossiaea foliosa, Hovea montana, Oxylobium ellipticum,Grevillea australis & Pimelea ligustrina) with potential to colonise in badly disturbed alpine and subalpine sites had a range of treatments (scarification,stratification, leaching, chemical soaks, freezing & diurnally fluctuating temperatures) applied to them to enhance germination success. Seeds of the hard seeded legumes responded well to scarification and stratification treatments. Acacia obliquinervia was scarified with boiling water which resulted in enhanced germination success. The scarification treatment with the best result was nicking for the other four legumes. The use of hot-watersoaks for these other legumes, of a minute or less showed some potential as a useful scarification treatment Stratification periods between 8 to 14 weeks for Acacia alpina, 12 to 14 weeks for Bossiaea foliosa, 2 to 8 weeks for Hoveamontana and 4 to 6 weeks for Oxylobium ellipticum gave significantly enhanced germination. Grevillea australis did not respond to germinationpre-treatments, except for an isolated case of nicking and stratification for 6weeks. The same treatment of older seed did not result in significantgermination. Pimelea ligustrina did not reliably respond to germination pretreatments.Germination trial results were then applied to one of the legumespeCIes (Bossiaea foliosa) as a guide to how these seeds respond to apretreatment before sowing on a disturbed site at the Bogong High Plains.The treatment of 30s in water @ l00°C and 14 weeks stratification before sowing in autumn was found to significantly enhance the field establishment success of Bossiaea foliosa.
520

Sleep and Breathing at High Altitude

Johnson, Pamela Lesley January 2008 (has links)
Doctor of Philosphy (PhD) / This thesis describes the work carried out during four treks, each over 10-11 days, from 1400m to 5000m in the Nepal Himalaya and further work performed during several two-night sojourns at the Barcroft Laboratory at 3800m on White Mountain in California, USA. Nineteen volunteers were studied during the treks in Nepal and seven volunteers were studied at White Mountain. All subjects were normal, healthy individuals who had not travelled to altitudes higher than 1000m in the previous twelve months. The aims of this research were to examine the effects on sleep, and the ventilatory patterns during sleep, of incremental increases in altitude by employing portable polysomnography to measure and record physiological signals. A further aim of this research was to examine the relationship between the ventilatory responses to hypoxia and hypercapnia, measured at sea level, and the development of periodic breathing during sleep at high altitude. In the final part of this thesis the possibility of preventing and treating Acute Mountain Sickness with non-invasive positive pressure ventilation while sleeping at high altitude was tested. Chapter 1 describes the background information on sleep, and breathing during sleep, at high altitudes. Most of these studies were performed in hypobaric chambers to simulate various high altitudes. One study measured sleep at high altitude after trekking, but there are no studies which systematically measure sleep and breathing throughout the whole trek. Breathing during sleep at high altitude and the physiological elements of the control of breathing (under normal/sea level conditions and under the hypobaric, hypoxic conditions present at high altitude) are described in this Chapter. The occurrence of Acute Mountain Sickness (AMS) in subjects who travel form near sea level to altitudes above 3000m is common but its pathophysiology not well understood. The background research into AMS and its treatment and prevention are also covered in Chapter 1. Chapter 2 describes the equipment and methods used in this research, including the polysomnographic equipment used to record sleep and breathing at sea level and the high altitude locations, the portable blood gas analyser used in Nepal and the equipment and methodology used to measure each individual’s ventilatory response to hypoxia and hypercapnia at sea level before ascent to the high altitude locations. Chapter 3 reports the findings on the changes to sleep at high altitude, with particular focus on changes in the amounts of total sleep, the duration of each sleep stage and its percentage of total sleep, and the number and causes of arousals from sleep that occurred during sleep at increasing altitudes. The lightest stage of sleep, Stage 1 non-rapid eye movement (NREM) sleep, was increased, as expected with increases in altitude, while the deeper stages of sleep (Stages 3 and 4 NREM sleep, also called slow wave sleep), were decreased. The increase in Stage 1 NREM in this research is in agreement with all previous findings. However, slow wave sleep, although decreased, was present in most of our subjects at all altitudes in Nepal; this finding is in contrast to most previous work, which has found a very marked reduction, even absence, of slow wave sleep at high altitude. Surprisingly, unlike experimental animal studies of chronic hypoxia, REM sleep was well maintained at all altitudes. Stage 2 NREM and REM sleep, total sleep time, sleep efficiency and spontaneous arousals were maintained at near sea level values. The total arousal index was increased with increasing altitude and this was due to the increasing severity of periodic breathing as altitude increased. An interesting finding of this research was that fewer than half the periodic breathing apneas and hypopneas resulted in arousal from sleep. There was a minor degree of upper airway obstruction in some subjects at sea level but this was almost resolved by 3500m. Chapter 4 reports the findings on the effects on breathing during sleep of the progressive increase of altitude, in particular the occurrence of periodic breathing. This Chapter also reports the results of changes to arterial blood gases as subjects ascended to higher altitudes. As expected, arterial blood gases were markedly altered at even the lowest altitude in Nepal (1400m) and this change became more pronounced at each new, higher altitude. Most subjects developed periodic breathing at high altitude but there was a wide variability between subjects as well as variability in the degree of periodic breathing that individual subjects developed at different altitudes. Some subjects developed periodic breathing at even the lowest altitude and this increased with increasing altitude; other subjects developed periodic breathing at one or two altitudes, while four subjects did not develop periodic breathing at any altitude. Ventilatory responses to hypoxia and hypercapnia, measured at sea level before departure to high altitude, was not significantly related to the development of periodic breathing when the group was analysed as a whole. However, when the subjects were grouped according to the steepness of their ventilatory response slopes, there was a pattern of higher amounts of periodic breathing in subjects with steeper ventilatory responses. Chapter 5 reports the findings of an experimental study carried out in the University of California, San Diego, Barcroft Laboratory on White Mountain in California. Seven subjects drove from sea level to 3800m in one day and stayed at this altitude for two nights. On one of the nights the subjects slept using a non-invasive positive pressure device via a face mask and this was found to significantly improve the sleeping oxyhemoglobin saturation. The use of the device was also found to eliminate the symptoms of Acute Mountain Sickness, as measured by the Lake Louise scoring system. This finding appears to confirm the hypothesis that lower oxygen saturation, particularly during sleep, is strongly correlated to the development of Acute Mountain Sickness and may represent a new treatment and prevention strategy for this very common high altitude disorder.

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