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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.
21

A rights perspective on the global trade in rhino horn

Bowles, Warren Alan 04 June 2014 (has links)
LL.M. (Human Rights Law) / Figures released recently by the South African Department of Environmental Affairs indicate that rhino are being poached in South Africa at an alarmingly high rate, meaning that they are being used like a never-ending commercial resource. It has been debated in South Africa that, if legal trade in rhino horn were to be introduced, it may be a solution to curbing rhino poaching. There are animal rights views that condemn the use and exploitation of nonhuman animals for the financial gain of human beings, one of the foremost rights views being that of Tom Regan. In his view, he proposes ways in which nonhuman animals can be perceived as more than just commercial resources. He elaborates on how nonhuman animals can be regarded as beings in their own right with a unique value that entitles them to respectful treatment and, at the very least, protection from harm and cruel treatment. Analyses and arguments made in this dissertation are not rooted in what the economic consequences of having trade in rhino horn would be. They are rooted in morality and in law to demonstrate why trade should be seen as a solution that is a last resort to curbing rhino poaching. The first chapter of this dissertation concerns itself with unpacking the central tenets and principles of Regan’s rights view in the context of how nonhuman animals can be regarded as beings rather than resources. The second chapter provides an analysis of approaches in environmental ethics that are relevant for preserving the rhino for future generations and how this could be achieved with reference to Regan’s rights view. The third chapter deals with the application of Regan’s rights view to legal and illegal trade in rhino horn. This will also include evaluation of plausible methods for securing rhino horn that are available in the event that legal trade in rhino horn is accepted as a solution to the current rhino poaching situation in South Africa.
22

Ecology and Conservation of Endangered Species in Sumatra: Smaller Cats and the Sumatran Rhinoceros (Dicerorhinus Sumatrensis) As Case Studies

Pusparini, Wulan 29 August 2014 (has links)
While we should celebrate the bicentennial of naming the Sumatran rhinoceros (SR), the only extant population on earth might be on the island of Sumatra. Since Strien's 1986 study in Mamas Valley, Leuser, very little more has been learned about how this species distributed and what factors are influencing its extirpation. This study is the first conducted in Sumatra at an Island-wide scale. Using hierarchical models, I estimate the occurrence rates (%) and indices of abundance of SR on three remaining population areas: Leuser Landscape (LL) in 2007 (2.77%, 26 (CI 12-61)), Way Kambas (WK) in 2008 (33.58%, 27 (CI 14-50)) and Bukit Barisan Selatan (BBS) in 2010 (36.4%, 31 (CI 19-66)). Primary dry land forest and rivers are factors affecting SR occurrence in LL, but the index of abundance also is affected by deforestation, roughness of terrain, and and a vegetation index. The index of abundance in WK is more affected by major roads, and brush and savannah cover types, and the occurrence there is additionally affected by deforestation. Secondary dry land forest, regular roads, and deforestation is affecting both the occurrence rate and index of abundance of SR in BBS. The identification of these environmental and disturbance factors is translated into spatially explicit map that can be used to update the IUCN distribution map. In LL, by comparison to the historical distribution based on Strien (1986), the small population in Bendahara Mountain might still persist outside the core population in Mamas Valley.
23

The occurrence of piroplasms in various South African black rhinoceros (Diceros bicornis) populations

Zimmerman, David Edwin 02 March 2010 (has links)
Between November 2002 and October 2006, blood samples were collected from 46 black rhinoceroses (Diceros bicornis) originating from various national parks and game reserves within South Africa. The samples were divided into two groups, based on the black rhinoceros subspecies from which they originated: twenty-eight (n = 28) of the samples originated from subspecies D. b. bicornis, and eighteen (n = 18) from subspecies D. b. minor. DNA was extracted; the V4 hypervariable region of the 18S rRNA gene amplified and subjected to the Reverse Line Blot (RLB) hybridization assay. The RLB results demonstrated the presence of either Theileria bicornis or Babesia bicornis in 9 of the 46 samples examined. A further three PCR products failed to hybridize with any of the Babesia or Theileria species-specific probes, and only hybridized with the Babesia/Theileria genus-specific probe, suggesting the presence of a novel species or variant of a species. Samples collected from black rhinoceroses originating from the more arid areas of South Africa, Tswalu Game Reserve and the old Vaalbos National Park, were found to be apparently free of T. bicornis and B. bicornis piroplasms. Based on these findings, it was concluded that B. bicornis and T. bicornis are relatively widespread in black rhinoceros populations in South Africa and pose a potential risk to the success of metapopulation management programs. Of the two black rhinoceros subspecies that occur in South Africa, D. b. bicornis is at greater risk due to their apparently Babesia/Theileria-naïve status in certain areas, when compared to the subspecies D. b. minor. Conservation managers need to carefully evaluate methods and procedures during the translocation of black rhinoceroses, especially when relocating from geographically and climatically diverse ecosystems and more so when dealing with the subspecies D. b. bicornis. Copyright / Dissertation (MSc (Veterinary Tropical Diseases))--University of Pretoria, 2009. / Veterinary Tropical Diseases / unrestricted
24

Seasonal Changes in Behavior and Exhibit Use of Captive African Elephants (Loxodonta africana) and Black Rhinoceroses (Diceros bicornis)

Mueller, Jenni Elizabeth 08 July 2008 (has links)
No description available.
25

The Structure of L-System

Chiu, Po-Hung 10 September 2015 (has links)
No description available.
26

Determination of the botanical composition of black rhinoceros (Diceros bicornis) dung using the rbcL gene as a molecular marker, and analysis of antioxidant and phenolic content of its browse

Bulani, Siyavuya Ishmael 25 June 2013 (has links)
The black rhinoceros remains one of the world's extremely endangered species despite a variety of policies to protect it. The black rhinoceros population at the Great Fish River Reserve (GFRR) in the Eastern Cape in South Africa has increased steadily since their re-introduction in 1986. This megaherbivore is a browser, with a diet obtained largely from the short and medium succulent thicket of the GFRR. Knowledge of the preferential diet of the black rhinoceros on the reserve is an important factor for the effective management of the land and the herbivores that compete for its resources. The dietary preferences of the black rhinoceros at the reserve have been established using backtracking methods. In this study the rbcL gene was used to establish an rbcL gene database of the plants from the GFRR and determine the botanical composition of the black rhinoceros dung from the GFRR. Due to the limited number of rbcL gene plant sequences from the GFRR deposited in the GenBank database, 18 plant species from the GFRR were sequenced. Sequence analyses between the partial rbcL gene sequences generated were able to distinguish between plants down to species level. Plant species from the family Euphorbiaceae and Fabaceae showed sequence variation at intra-specific level compared to those of Tiliaceae which were more conserved. The generated rbcL gene sequences from seasonal dung samples were compared to the rbcL gene sequenced from 18 plant species obtained from the GFRR and those from the GenBank database. A wide range of plant species were identified from the dung samples. There were no major differences in botanical composition between the dung samples, except that Grewia spp. were found to dominate in almost all seasons. The results obtained on the free radical scavenging activity of the extracts against 2,2-Diphenyl-l-picrylhydrazyl (DPPH) increased in the order of methanol > ethyl acetate > chloroform. The DPPH free radical scavenging activity of the methanol plant extracts increased in the order Brachylaena elliptica > Plumbago auriculata > Grewia robusta > Azima tetracantha. Methanol extracts on the TLC plate sprayed with Fe³⁺-2,4,6-Tri-2-pyridyl-s-triazine (TPTZ) showed that the compounds present in the extracts react differently to ferric ion, with most compounds unable to reduce ferric ion. Furthermore the methanol extracts were able to exhibit reduction potentials vs. Ag/AgCl at low concentrations. The compounds in the extracts were shown to be phenolic acids and flavonoid glycosides.
27

A survey of the available browse for the black rhinoceros (Diceros bicornis ssp. bicornis Linnaeus, 1758) in a farmland area in the Kunene region, Namibia

Olsson, Sanna January 2015 (has links)
No description available.
28

Molecular and biochemical analysis of the diet of the black rhinoceros

Kgopa, Ananias Hodi 15 July 2013 (has links)
The black rhinoceros, Diceros bicornis, is listed as critically endangered. The black rhinoceros population in the Great Fish River Reserve (GFRR) has increased steadily to a current estimate of one hundred animals since the re-introduction of four animals in 1986. In an effort to contribute to the effective conservation and management of this species, dietary composition was studied in the medium Portulcaria thicket vegetation of the GFRR. This study used a molecular approach to determine the diet of the black rhinoceros of the GFRR by sequencing the ribulose bisphosphate carboxylase large subunit (rbcL) gene in plants and dung. Twenty-three plant species were collected from the reserve, and 802 bp of the rbcL gene were sequenced. These plant sequences were used as a reference database for the identification of plant sequences generated from black rhinoceros dung. Initial studies investigated the amplification, cloning and sequencing of DNA extracted from the dung samples which indicated the viability of the molecular approach. Thereafter, dung generated rbcL DNA was analyzed by GS FLX sequencing. Of the plant sequences identified by comparison to the GenBank database, Carissa bispinosa was the most prevalent. The study further characterized the antioxidant activities and phenolic content of plants eaten by the black rhinoceros using four different assays. Phyllanthus verrucosus, Putterlickia pyracantha, Maytenus capitata, Euclea undulata and Ozoroa mucrunata consistently had high antioxidant activities when assayed against 2,2-azinobis (3-ethyl benzothiazolium-6-sulfonic acid) (ABTSʹ⁺), 2,2-diphenyl-1-picrylhydrazyl (DPPHʹ), and ferric reducing antioxidant potentials (FRAP) and phenolic content when evaluated using the Folin-Ciocalteu assay. The majority of plants investigated showed low antioxidant potentials and low phenolic content. The extent to which antioxidants influenced the browse selection by the black rhinoceros remains inconclusive.
29

Využití programu Rhinoceros při výuce Deskriptivní geometrie / Usage of computer program Rhinoceros in the lessons of Descriptive geometry

ČEČKOVÁ, Veronika January 2007 (has links)
This work is about the acquaintance with the possibilities and manipulation of CAD program Rhinoceros and its usage in lessons. First of all the work is focused on descriptive geometry and its imagination in space. It is also about the assessment of advantages and disadvantages of chosen program in lessons.
30

The demography, spatial ecology and reproductive success of the black rhinoceros, Diceros bicornis, in Hluhluwe-iMfolozi Park, Kwazulu-Natal, South Africa

Nhleko, Zoliswa Nombulelo January 2014 (has links)
Black rhinoceroses (Diceros bicornis) are endangered; there are only ~5000 individuals remaining worldwide. Consequently, black rhinos are managed as a metapopulation in southern Africa. This means that even though several sub-populations of black rhinos are geographically separated, they are managed as a single population. This is achieved by interchanging genetic material between the sub-populations. The main aim of the metapopulation management approach is to increase black rhino numbers in the sub-region. The Rhino Management Group (RMG), formed in 1989, was tasked with setting scientifically defensible demographic targets for the remaining black rhino sub-populations in southern Africa. In the same year, the RMG set fecundity rate at 25% and stated that each black rhino sub-population should achieve a minimum growth rate of 5% per year. The black rhino population in the Hluhluwe-iMfolozi Park (HiP), KwaZulu-Natal, South Africa, is of international importance as it has historically been a significant donor population for the translocation of black rhinos to establish new subpopulations elsewhere in the sub-region. However, the black rhino population at HiP is performing poorly in terms of reproductive success. My study was initiated to assess the reproductive life-histories of the black rhino population at HiP and to determine whether the population was meeting the demographic targets set by the RMG. I also wished to assess the use of space by black rhinos in HiP as a potential explanation for the observed reproductive output. Detailed life-history information for known black rhinos (n = 120) was used to investigate reproductive success between 1998 and 2012. The mean age at sexual maturity (ASM) was determined as 12 years, which is higher than the ASM found in black rhino populations that are considered to be performing poorly (ASM = ~ 7 years). The intercalving interval (ICI) was three years, nine months; this was also longer than the ICI of most black rhino populations. Further, the 2012 black rhino population at HiP had a growth rate of 6.4%, and the population comprised 60% adults, 23% sub-adults and 13% juveniles. Such demographics are usually observed in stable populations and it is possible that poor habitat quality could be resulting in the delayed ASM and longer ICI’s at HiP. In addition, 5% of the population is removed annually as part of the Black Rhino Range Expansion Program (BRREP) to establish new sub-populations. This could also be negatively influencing the reproductive performance of the HiP population. To determine the home range and habitat use of black rhinos at HiP, field data from 13 individual adult black rhinos (n = 9 females and 4 males) over a two-year period (2011-2012) were analyzed. Black rhino female home ranges were slightly smaller (15.4 ± 12.9 km²) than the home ranges of males (23.3 ±14.0 km²) and both sexes utilized similar habitats in the centre of the park. In addition, both the male and female black rhinos were found closer to rivers and drainage lines than expected. However, the assessment of black rhino space use in HiP was limited by a small sample size, making inferences of the impact of space use on reproductive success difficult. Nevertheless, my study suggests that food availability likely influences the location and sizes of black rhino home ranges at HiP. I believe that my study forms the first step in understanding the factors that influence the reproductive success and habitat use patterns of the current black rhino population at HiP. The information produced by my study should enable park management to identify future research to be conducted at HiP, which will yield more robust data for making informed black rhino management decisions at HiP and elsewhere.

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