210 research outputs found
The development of English-language hymnody and its use in worship : 1960-1995.
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN039276 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
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Spatial Ecology and Population Dynamics of Tule Elk (Cervus elaphus nannodes) at Point Reyes National Seashore, California
No full textThe tule elk (Cervus elaphus nannodes) was reintroduced to Point Reyes National Seashore, California in 1978. After exhibiting irruptive growth for 20 years, elk abundances have fluctuated. Three subpopulations of elk currently inhabit Pt. Reyes: a fenced subpopulation at high density; a free-ranging subpopulation in designated wilderness at low density; and a free-ranging subpopulation on active ranchland at low density. Little is known about the spatial ecology and population dynamics of tule elk. This unusual situation provided an opportunity to quantify and compare factors affecting the home ranges, group sizes, resource selection, small-scale movements and population dynamics of tule elk. I collected biweekly fixes on radio-collared elk cows between 2005 and 2008 to examine herd structures, space use patterns, grouping behavior and survival rates of tule elk. Radio-telemetry data revealed 6 herds of elk at Pt. Reyes (4 at Tomales), which had distinct herd ranges and showed little spatial interaction. Fixed kernel home ranges were some of the smallest for elk in North America (217 ha, SE = 35), and were negatively correlated with elk density. Home range sizes were 300% smaller than previous estimated for elk at Pt. Reyes in 1998. The sizes of elk groups peaked during the winter and mid-summer, and were smallest during the spring parturition and fall rutting periods. Elk with larger home range sizes generally formed smaller groups. Resource selection function (RSF) results indicated that tule elk at Pt. Reyes selected flat, grassland-dominated habitats over hilly, scrub and forest habitats; although resource selection patterns varied among herds. Elk shifted to lower elevations, steeper slopes and more scrub-dominated habitats during the dry season (May - October). Most elk showed an aversion to areas close to roads and trails, but this result was not consistent across all herds. I quantified small-scale movement patterns of tule elk using hourly fixes from GPS-collared elk. Elk exhibited daily cycles in their movement patterns by increased their hourly movements in the morning and evening hours. Elk daily movements were longest during wet spring months and shortest during the dry fall months. Elk slowed when traveling through homogeneous grassland habitat. Windy conditions caused elk to slow, but precipitation had no effect on elk movement. Elk moved faster when closer to roads and trails. Elk in higher density herds moved slower on an hourly scale than lower density herds, but herd density had no affect on daily movement patterns. Using known-fate models applied to radio-telemetry data, I estimated annual cow elk survival was 0.96 (SE = 0.02). I captured and monitored radio-collared elk calves from 2005 to 2007 to estimate calf survival and causes of mortality. Using known-fate models, I estimated annual survival for elk calves was 0.81 (SE = 0.02). The primary cause of death for both cows and calves was starvation, which was often accompanied by copper and selenium deficiencies. Sensitivity and elasticity estimates of elk vital rates revealed that adult cow elk survival contributed the most (30%) to elk annual population change (λ). The D Ranch and Limantour herds were expected irruptive growth and by 2018 increase to 393 and 389 elk, respectively, based on stochastic population projection models. The projected future abundance of elk in the Tomales herds was dependant on the previous year's annual rainfall: models projected increases in elk abundance following years of above-average rainfall but no change in elk abundance following years of below-average rainfall. Future growth of the D Ranch and Limantour elk herds will likely concentrate on adjacent ranchlands, given RSF models results, and will likely result in future conflicts between NPS management, unless proactive actions are taken
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Survey and Analytical Methods for Long-Term Monitoring of Wildlife Metacommunities in California Montane Forests
No full textLong-term, large-scale monitoring of wildlife metacommunities is needed to recognize population declines early enough to identify environmental stressors and facilitate adaptive planning. Potential outcomes include information supporting the designation of new species of conservation concern, or better yet, conservation actions that avert the need for conferring critical statuses. By surveying multiple species, declines of individual species need not be considered in isolation, but can be compared to responses of other species in the metacommunity. However, multi-species monitoring presents a variety of new challenges in terms of appropriate survey methods and analytical techniques for drawing valid ecological inferences. In this study, I investigated several related aspects of multi-species monitoring. One theme was the role of automated survey methods (e.g., audio recorders and camera stations) that leave a permanent record and easily provide for temporal replication of surveys. I applied occupancy models to repeat surveys for addressing detection probability and providing unbiased estimates of species occurrence. Lastly, I evaluated several novel quantitative methods for comparing community properties using monitoring data. In the first chapter I considered the effectiveness of automated recorders for monitoring common birds in California forests. I applied single-species occupancy models to 46 species using 5 years of monitoring data in which automated recorders were placed at 453 random sites across a 5.4-million-ha northern California study area. The devices were programmed to record sounds during up to 3 surveys each morning on 3 consecutive days during the breeding season when songbirds were singing from territories. Skilled interpreters reviewed these recordings to identify all species heard during each survey. With Monte Carlo simulation and results from occupancy models, I demonstrated 80% power for monitoring declines as small as 2.5% per year over 20 years for 32 species given a sampling effort of 100 new sites per year. I also determined an effective survey area radius of 30 m to 50 m for automated recorders, and showed that the devices provided similar occupancy estimates as traditional point counts despite lower survey-level detection probability. In the second chapter I applied multi-species occupancy models to the calculation of biodiversity indices describing metacommunity organization. I used the same automated recorder data set for birds from Chapter One. Specifically, I applied simulation and Bayesian hierarchical models to demonstrate how a failure to address detection probability heterogeneity underestimates the evenness of species occupancy distributions. In models of the bird data I found that a number of species traits (migration, foraging guild, territoriality, body size) were informative in explaining detection probability. By pooling information from common species in a multi-species model, I was able to draw stronger inferences about rarer species than by modeling these species individually. Lastly, I illustrated the ecological significance of species-traits modeling and found that warbler and woodpecker occupancies were evener than for sparrows. In the third chapter, I proposed a new quantitative method for comparing species abundance distributions. I illustrated this method using avian point count surveys from 4 research forests in California. I applied bootstrap resampling to probabilistically compare the abundances of intermediate ranks among and within species abundance distributions. I found higher abundances of intermediately-common species on 2 of the forests, and ascribed this finding to differences in forest productivity and habitat complexity leading to greater niche partitioning of resources. At the metacommunity-level, I found higher abundances of intermediately-common species for neotropical migrants compared to resident birds. In the fourth chapter, I considered the use of baited camera stations for monitoring Pacific fisher (Pekania pennant pacifica) and other mammals. Cameras were placed at 172 randomly selected forest sites across 2.8 million ha of northwestern California. The duration of each survey was 2 to 4 weeks. I estimated regional occupancy from these data at 2 survey scales (e.g., individual sites [0.465] and pairs of sites 1.6 km apart [0.651]). I also demonstrated 80% power for monitoring declines as small as 2.0% per year over 20 years given a sampling effort of 100 new sites per year. Lastly, I calculated the median latency to first detection for 13 other species of mammals detected at > 5% of sites, showed that latency was < 6 days for 10 of these species, and argued that these results strengthen the case for expanding the use of camera traps to multi-species monitoring
Landscape-painter as landscape-gardener : the case of Alfred Parsons R.A.
No full textIn 2 vols.Available from British Library Document Supply Centre-DSC:DXN016830 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
Vascular endothelial growth factor and basic fibroblast growth factor expression in esophageal adenocarcinoma and Barrett esophagus
No full textAbstractObjective: This study was undertaken to investigate the role of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor in the development and progression of Barrett esophagus and adenocarcinomas of the esophagus and gastroesophageal junction. Methods: Vascular endothelial growth factor and basic fibroblast growth factor messenger RNA expression levels, relative to the control gene encoding β-actin, were measured by using a quantitative reverse transcription-polymerase chain reaction method (ABI 7700 Sequence Detector system) in specimens of Barrett intestinal metaplasia (n = 16), dysplasia (n = 11), adenocarcinoma (n = l 5), and matching normal squamous esophageal tissues (n = 35). Vascular endothelial growth factor and basic fibroblast growth factor protein expression and CD31+ microvessel density were assessed by means of immunohistochemistry in 25 tissue sections that included representative areas for each of these Barrett stages. Results: Expression levels were significantly increased in adenocarcinoma compared with in either normal squamous mucosa (P <.0001 for both genes) or intestinal metaplasia (vascular endothelial growth factor, P =.002; basic fibroblast growth factor, P <.0001). Vascular endothelial growth factor levels were also significantly higher in cancer tissues compared with dysplasia tissues (P =.024, Mann-Whitney U test). Basic fibroblast growth factor expression was also significantly increased in Barrett dysplastic mucosa compared with in intestinal metaplasia or normal esophageal mucosa. Microvessel density was generally higher in adenocarcinoma compared with in preneoplastic Barrett tissues. The pattern of vascular endothelial growth factor and basic fibroblast growth factor protein expression was similar to the messenger RNA expression pattern, with the exception that mucin-containing goblet cells stained intensely for vascular endothelial growth factor and only weak vascular endothelial growth factor staining was present in some adenocarcinomas. Conclusions: Vascular endothelial growth factor and basic fibroblast growth factor messenger RNA expression levels are significantly upregulated in esophageal and gastroesophageal junction adenocarcinomas, suggesting a role for these angiogenic factors in the development of these cancers. Vascular endothelial growth factor and basic fibroblast growth factor messenger RNA expression levels are also increased in some Barrett esophagus tissues, with this increase occurring at an earlier stage for basic fibroblast growth factor than for vascular endothelial growth factor. Basic fibroblast growth factor protein expression pattern is similar to the messenger RNA expression pattern, but unlike the messenger RNA findings, vascular endothelial growth factor protein expression is strongest in goblet cells.J Thorac Cardiovasc Surg 2003;125:246-5
History and status of introduced ungulates on Rancho Piedra Blanca, California
No full textMaster of Science (MS)Natural Resources and EnvironmentUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/97702/1/39015003284448.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/97702/2/39015003284448.pd
Contribution of Prof. H. W. E. Ntsan\u27wisi in the Development of the Mhala Area
No full textThis article is based on the presentation that the author made at a conference that was organised by the Oral History Association of South Africa (OHASA) and that was held in Mthatha, Eastern Cape on October 12, 2017. The theme of the conference was “Oliver Reginald Tambo in Memoriam: Reminiscing on a Centenary of Struggle.
Some chemical problems in geology
No full textThis thesis is in the main a compilation of the views held at this institution in regard to the problems discussed as interpreted by the author. No claims for originality are made except in the manner of presentation as the material used has been obtained by conference and class room work with Professor V. H. Gottschalk and Professor G. H. Cox and also to some extent with H. A. Buehler, State Geologist. On the other hand the material is an expression of these ideas as assimilated by the author and hence may in certain cases differ radically from the views held by those mentioned above. It is hoped that this thesis may serve as an outline for future study of the subjects discussed and its main value is as such rather than as a contribution to the knowledge of chemical geology. With this in mind the bibliographies have been prepared with some care although they are by no means complete --Introduction, page [2]
The Lateralis Group of the Bombylid Genus Villa
No full textAuthor Institution: Department of Zoology and Entomolog
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