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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.
31

Clustering and incubation in Africa’s small business development: some experiences and lessons

Chisenga, Desmond Chalwe January 2012 (has links)
Magister Economicae - MEcon / There is a general recognition and acceptance that small and medium enterprises (SMEs) are important contributors to social and economic development. However, in Africa which hosts many developing economies, SMEs must endure numerous challenges that tend to repress small enterprise development. Formal cluster development programmes have been identified as one progressive way of assisting SMEs to overcome the obstacles. It involves deliberately instituting and supporting small enterprise clusters. Although this idea of formal clustering of firms is relatively new to Africa, cluster development programmes are increasingly taking the form of small business incubation. Business incubation essentially aims to provide a systematic method of rendering business support services to fledgling small businesses to help them continually rise above market challenges and thrive. Some governments in Africa have embraced the notion and are incorporating plans into their local economic development (LED) programmes to enhance small business development through incubation. Countries like South Africa, Ghana, Kenya, and Nigeria have amongst the most conspicuous incubator programmes and cluster experiences on the African continent. This study interrogates the effectiveness of and hence the scope for formal business incubation or rigid clustering programmes in Africa. It assesses examples of both rigid and flexible clusters in a few African countries in order to identify their main differences and to thus establish some critical areas of business clustering needed for useful small and medium enterprise development in Africa. Upon reviewing case study literature, it is observed that formal incubation programmes are likely to be less effective in creating new SMEs compared to the more flexible clusters in Africa. Rigid clusters also tend to rely heavily on state funding, are more subjected to political interference, are prone to expansion capacity constraints, and are unlikely to sustain themselves financially in the long run. The study notes that rigid clustering mainly favours a high-tech environment. Hence, incubation programmes may be more suitable for advanced economies. For low-tech industries, on the other hand, formal business incubation may be inappropriate.
32

Life history tradeoffs, incubation behavior and conservation of horned larks (Eremophila alpestris)

Camfield, Alaine Francine 11 1900 (has links)
Nearly 30 percent of the earth’s terrestrial surface is mountainous and despite representing a large proportion of the planet’s protected areas, the ecology of vertebrates in high elevation areas have received little attention from researchers and managers. I studied two subspecies of horned larks (Eremophila alpestris articola and E. a. strigata) that breed at high elevation and latitude in British Columbia, Canada and at low elevation and latitude in Washington, USA, respectively. I addressed the question of how the life history of alpine breeding songbirds differs from their low elevation conspecifics and showed that life history variation can be found among closely related groups. My results were consistent with other comparative demographic studies which suggest that alpine vertebrate populations tend to show survivor life history strategies when compared to their low elevation counterparts. In addition, population growth rates were stable for E. a. articola suggesting that this subspecies is well adapted to the challenges of breeding in alpine environments. E. a. strigata, however, is declining rapidly and the remaining breeding habitats in Washington do not support stable populations. I used demographic models to show that within reasonable ranges for each vital rate (fecundity, adult and juvenile survival), management actions that target a single rate independently are unlikely to result in stable or recovering populations and management actions that target multiple vital rates should be prioritized. Finally, to further investigate adaptations of E. a. articola to alpine environments I examined how they modify their incubation behavior in response to changes in ambient temperatures which were generally well outside the optimal temperature range for normal embryonic development. Females adjusted the amount of time spent incubating by varying the frequency rather than the duration of recesses. At low ambient temperatures they appeared to shift their investment toward the survival of their eggs by increasing the total time spent on the nest instead of taking longer or more frequent foraging bouts. Overall, the results of my study indicate that alpine populations of horned larks have life history traits and breeding behaviors that allow them to persist in these areas despite the challenging breeding conditions. / Forestry, Faculty of / Graduate
33

Exploring the influence of funding sources on business incubation in the Western Cape

Milne, James 10 February 2021 (has links)
The topic of business incubation has been the subject of considerable academic research, and a focal point in entrepreneurship support ecosystems. Business incubators provide entrepreneurs and start-up businesses with a shared space (either physical or virtual). The incubator offers a systematic shared support structure that enhances businesses' chances of succeeding and growing into entities that eventually graduate to a location beyond the ‘safety net' of the incubator. Academic research in the field of incubation has predominantly focused on (i) understanding business incubation models that are most effective within particular operating environments; and (ii) understanding support services that are most useful to incubatees of the incubator. This research instead explores the influence that funding sources have on business incubators, with a focus on understanding how incubators in turn assist their incubatees in accessing finance. Research focusing on funder influence on incubators, and support provided to incubatees to assist with access to finance, is at a nascent stage within the South African business incubation landscape. The research was undertaken utilising a multiple case study approach, with individual business incubators constituting a case. Incubators were classified into three case typologies, depending on their predominant funding source: mixed; private; or public funded. From the population of business incubators in South Africa, a sample of 8 incubators within the Western Cape Province were selected. Semi-structured interviews with participants were undertaken over a three month period and involved undertaking interviews with 8 incubator managers, and 10 current or former incubatees. Qualitative data from participant interviews were analysed using a combination of NVivo12 and MS Excel, in order to determine responses relevant to the research question and subquestions. The information collected was categorised into themes of relevance using initial and pattern coding methodologies. The research suggests that funders influence the work of incubators through driving their own objectives, utilising the incubator as a tool. Public sector funders set objectives for incubators that were linked to achieving socioeconomic goals (poverty alleviation and economic redress). Public sector funders were found to be strongly focused on achieving their own performance indicator goals, even if these did not align to the work of the incubators. Private sector funders set objectives for incubators that were linked to achieving the goals of their organisation or fund mandate. Private sector funders were found to lack long-term commitment to funding incubators. Communication between public and private sector funders was found to be, in general, poorly co-ordinated. Lack of co-ordination between funders negatively affected the impact of incubators. The cross-case multiple case study methodology revealed that in the Western Cape, similarities exist in the channels of support provided by incubators to assist their incubatees in accessing funding, regardless of the funding structure of the business incubator. However, heterogeneous priorities exist in funding support services provided to incubatees. Bias was identified in the process of sourcing of funding for incubatees. Incubators pursued a blend of proactive and reactive approaches to accessing funding for their incubatees, depending on their relationship with funder(s). The researcher recommends a strengthening of efforts to co-ordinate objectives across the two broad spheres of incubator funding sources (public and private) in order to build effective and sustainable business incubators in South Africa. Financiers of incubators should review stakeholders and other financiers involved in the incubator to clarify policy, commitments and performance metrics. Emphasis must be placed on ensuring alignment (i) between incubator financiers; (ii) between the objectives of the financier(s) and the incubator. The current study is well suited to being expanded in future, both in terms of: (i) widening the interview participant base to include incubator financiers; (ii) a geographic expansion to focus on South Africa as a whole.
34

WHAT MECHANISMS UNDERLIE SYNCHRONOUS HATCHING IN LOGGERHEAD TURTLE NESTS?

Unknown Date (has links)
The goal of this study was to determine if hatching synchrony occurs in loggerhead sea turtle nests and if it does, what mechanism(s) promote that synchrony. Synchrony may occur because oviposition takes place during a single evening, and because incubation temperatures within the nest show relatively little variation; thus, rates of embryonic development among the eggs are similar ("temporal synchrony hypothesis"). Alternatively, synchrony might be enhanced through embryo-to-embryo communication that stimulates and synchronizes development ("coordinated hatching hypothesis"). Experiments were designed to distinguish between these two hypotheses. I found that if only a few embryos survive, temporal synchrony occurs. However, if many embryos survive, the duration of incubation and hatching shortens, presumably because embryonic movements inside soft-shelled eggs are detected by and transmitted between eggs and stimulate development, expediting hatching synchrony. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
35

Assessing the Effects of Incubation Temperature on the Cognitive Ability of Hatchling Loggerhead (Caretta caretta) Sea Turtles

Unknown Date (has links)
Under the expected warmer temperatures due to climate change, sea turtle embryos may be subjected to thermal conditions detrimental to nest success and hatchling quality; one trait which may be negatively affected is cognitive ability. In this study, loggerhead sea turtle eggs were acquired from Boca Raton, FL and lab incubated under two female-producing temperatures: an “optimal” temperature of 31°C and a sublethal temperature of 33°C. Cognitive ability of post-hatchlings, assessed via associative learning and reversal was investigated using a y-maze. The sublethal temperature decreased incubation duration, hatch success, hatchling growth rates and produced smaller hatchlings with significantly more scute anomalies. Hot hatchlings performed worse on the reversal, taking longer to train, and thus hint at an effect of incubation temperature on cognitive flexibility in loggerhead turtles. With temperatures rising on beaches in South Florida, this study provides evidence of further potential threats to hatchling quality and potentially even survival. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
36

Comparative Evaluation of Three Different Methodologies for Determining Embryo Temperature in Broiler Hatching Eggs During Incubation

Olojede, Opeyemi Christiana 14 August 2015 (has links)
Temperature is the most important among several factors that are needed for optimum avian embryonic development during incubation. Previous studies have implied that incubation temperature may have an impact on chick quality and post hatch performance. The use and accuracy of different methodologies for the estimation of embryonic temperature and eggshell conductance values during incubation were determined in three trials. Results suggested that air cell temperature using transponders may be used for the estimation of embryo temperature from 12 through 19 days of incubation and the subsequent calculation of eggshell conductance and specific eggshell conductance values. A final trial was conducted to further substantiate the estimation of embryo temperature using air cell readings by implanting probes alongside transponders in the air cell. It was determined that further modifications are needed to perfect this particular method.
37

The Development of a Pragmatic Methodology for the More Accurate Determination of the Core Body Temperature of Broiler Embryos During Incubation

Durojaye, Oluwaseun Ayobami 11 August 2017 (has links)
Avian embryonic development, hatchability, and post-hatch performance are greatly affected by temperature. Therefore, a pragmatic, minimally invasive, and industrially applicable method for the precise and accurate measurement of embryonic temperature is needed. The objective of this research was to develop such a method. Preliminary research concerning air cell depth profiles and the relationships of eggshell thickness to thermal gradients across the shells of broiler hatching eggs were determined. This provided information for appropriately positioning and timing wired thermistor probe insertion into egg air cells for the practical and accurate estimation of embryo temperature. The relationship between air cell temperature readings using transponders and wired thermistor probe network assemblies were likewise determined. Embryo temperature estimation using probes was shown to be a satisfactory, but their depth should be adjusted daily by 0.042 cm after Day 12 of incubation in order to mirror transponder temperature readings.
38

Effect of elevated embryonic incubation temperature on the temperature preference of juvenile lake (Coregonus clupeaformis) and round whitefish (Prosopium cylindraceum)

Harman, Adam January 2020 (has links)
Lake (Coregonus clupeaformis) and round (Prosopium cylindraceum) whitefish are two species of cold-adapted freshwater fish that spawn in shallow (<10m) cobble beds in the Laurentian great lakes. Developing whitefish embryos are potentially exposed to various anthropogenic sources of warming, including climate change and thermal effluents discharged in the nearshore environment. Several studies have investigated the effects of elevated incubation temperatures on whitefish embryos (particularly lake whitefish) but little work has been done to examine post-hatch effects. Thermal preferenda (temperature preference) describe the range of temperatures an organism will occupy when given a choice and are traditionally thought to be species-specific. Temperature preference can be modulated by a variety of abiotic and biotic factors including environmental temperature and is typically correlated with optimal growth temperature for a species. Assays for thermal preferenda require at least 24 hours, which includes a long tank-acclimation period that limits throughput and thus impacts replication in the study. A shuttle box thermal preference assay was optimized from 24-hours to 4-hours; length of acclimation time and trial length had no significant impact on thermal preference. Whitefish were incubated at natural and elevated temperatures until hatching; all groups were moved to common garden conditions (15°C) during the post-hatching stage. Temperature preference was determined at 12 months of age; lake whitefish were also tested at 8 months. Round whitefish displayed a significant decrease in temperature preference when incubated at 2°C and 6°C compared to 0.5°C. Lake whitefish had similar temperature preferences regardless of age and incubation temperature. This suggests that there is a difference in thermal tolerance between these species, as round whitefish were more sensitive to elevated incubation treatments. This thesis identified a persistent effect of elevated incubation treatments on the thermal preference of juvenile round whitefish, lasting up to 12 months post-hatch, which highlights the importance of examining sub-lethal thermal effects and thermal plasticity of cold-adapted species. / Thesis / Master of Science (MSc) / Lake and round whitefish are cold-adapted freshwater species that spawn in shallow coastal water in the Laurentian great lakes. Anthropogenic warming from various sources (e.g. climate change, thermal effluent) has been shown to reduce survival of whitefish embryos, but few studies have investigated the effects of elevated embryonic incubation temperatures on surviving juveniles. Fish typically prefer a small range of temperatures (temperature preference) that they will occupy if given a choice, which can be affected by a variety of factors including early life thermal exposure. This thesis shows round whitefish incubated at elevated temperatures (2°C, 6°C) display decreased temperature preference up to 12 months post-hatch, while lake whitefish had similar temperature preference regardless of incubation temperature. Therefore, this thesis provides more evidence that round whitefish are a more thermally sensitive species.
39

Selection for hatchability of Japanese quail embryos incubated at 102 F

Colvin, Wendy R. 03 March 2005 (has links)
A genetic selection study to determine the effects on egg hatchability and subsequent chick performance of Japanese quail (Coturnix japonica) eggs incubated at 100 F dry bulb temperature (Control, Line C) when compared to other eggs incubated at 102 F (Selected, Line S) was conducted over 10 consecutive generations. Eggs from a randomly mated population (designated as Generation 0) of Japanese quail maintained at the Oregon Agricultural Experiment Station were randomly allocated to two treatment groups (Lines C and S) and incubated at the different temperatures in separate but identical Jamesway 252 machines. On day 14 of incubation all eggs were transferred to a common hatcher (98.5 F). Using family-based selection, the chicks that hatched from the two lines were subsequently used as breeders (25 paired matings per line) and the resulting eggs from each line incubated at their respective temperatures for 10 consecutive generations. Following the 10th generation percent egg fertility and percent hatch of fertile eggs were greater in Line C vs. Line S (p<O.O3 and p<O.0001, respectively). Embryo development time was shortened in Line S by 24 hours and mean 4- or 5- week body weights were greater (p<0.001) in Line S. Ten-day post-hatch mortality increased greatly in Line S vs. Line C after generation 6 (p<0.001) and hen-day egg production decreased after generation 4 in Line S vs. Line C (p<0.0001). The results indicate that embryo development time can be reduced by high temperature incubation, but at the expense of reproductive traits such as egg production, fertility, and hatchability of fertile eggs. / Graduation date: 2005
40

Développement embryonnaire, détermination du sexe sensible à la température et phénologie des pontes sous contrainte du changement climatique : le cas de la tortue Caouanne (Caretta caretta) / Embryonic development, temperature-dependent sex determination and nesting phenology under climate change constraints : the case of the loggerhead turtle (Caretta caretta)

Monsinjon, Jonathan 20 December 2017 (has links)
Le climat affecte entre autre la phénologie, l’aire de distribution, le comportement et la physiologie des espèces. Le changement climatique a donc des répercussions sur chacun de ces facteurs. L’augmentation globale des températures prévue d’ici 2100 pourrait profondément modifier la biodiversité de l’échelle des espèces jusqu’à celle des écosystèmes. Les ectothermes, et en particulier les reptiles ovipares à détermination du sexe sensible à la température, font partie des organismes susceptibles d’être les plus vulnérables au réchauffement du climat puisque quasiment tous leurs traits d’histoire de vie dépendent de la température. L’origine et le maintien de ce mécanisme de détermination du sexe, pouvant conduire à un sex ratio fortement biaisé à l’échelle d’une population, reste une énigme pour les écologues. Parmi les nombreuses questions soulevées par la présence de ce mécanisme de détermination du sexe, la signification adaptative, s’il y en a une, de ce mécanisme est cruciale.Ce mécanisme de détermination du sexe rend-il les espèces plus vulnérables dans le contexte actuel du changement du climat ? Plusieurs hypothèses évolutives ont été proposées et des modèles de dynamique des populations sont disponibles pour répondre à ces questions. Cependant, prédire le sex ratio primaire en conditions naturelles, c’est-à-dire le sex ratio des nouveaux nés, reste un défi majeur à l’heure actuel. Ce manuscrit vise à apporter de nouveaux outils méthodologiques afin de correctement prédire le sex ratio d’une ponte en fonction de la température ressentie par les embryons au cours de l’incubation. Les tortues marines,quasiment toutes menacées, sont des espèces migratrices présentant toute ce mécanisme de détermination du sexe.Chez ces espèces, la phénologie des pontes est aussi sensible à la température du milieu. Ce type de plasticité phénotypique est probablement la stratégie la plus efficace pour pallier à un changement rapide du climat. Ce manuscrit apporte quelques éléments de réponse quant au potentiel adaptatif des tortues marines face au réchauffement climatique avec l’exemple de plusieurs populations de tortues Caouanne (Caretta caretta). / Climate affects, among other things, species’phenology, distribution range, behavior and physiology.Climate change thus impacts each of these factors. Global warming expected by 2100 might profoundly modify biodiversity from species to ecosystems. Ectotherms, and in particular oviparous reptiles with temperature dependent sex determination, are thought to be among the most vulnerable in the face of global warming because virtually all their life history traits depend on temperature.The origin and the persistence of temperature-dependent sex determination, which could lead to heavily biased population sex ratios, is still an enigma for ecologists. Among numerous issues related to this sex determining mechanism, understanding its adaptive significance, if there is one, is crucial. At another level, does this sex determining mechanism make species more vulnerable in the context of contemporary climate change ? Several evolutionary hypotheses have been proposed and population dynamic models are available to address these issues. However, predicting primary sex ratio, i.e., the sex ratio of hatchlings, in natural conditions currently remainsa challenge. This manuscript aims to bring new methodological tools to properly predict sex ratio of aclutch depending on temperature experienced by embryosthroughout incubation. Marine turtles, almost all being threatened, are migratory species that all exhibit this sex determining mechanism. For those species, nesting phenology is also sensitive to environmental temperature.This type of phenotypic plasticity is probably the most efficient strategy to keep up with rapid climate change.This manuscript provides some elements for understanding the adaptive potential of sea turtles in the face of global warming with the example of several).

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