517 research outputs found
An econometric analysis of the wildlife market in South Africa
Bibliography: leaves 149-155.Since there has been no comprehensive nationwide economic study on the expanding wildlife market in South Africa, the present study ventures into a relatively unexplored economic terrain in the hope that more studies will be stimulated in that direction. The study focuses, firstly, on presenting an economic overview of the current trends within the wildlife market of South Africa, attempting inter alia to demonstrate how the sustainable utilisation of wildlife can contribute to both conservation and the economy. Secondly, it is endeavoured to describe the demand for wildlife species at game auctions across South Africa, using a range of econometric modelling techniques
Supporting business students' transition into higher education : the case of marketing downloads
Dynamic surfaces for mesenchymal stem cell self-renewal and differentiation
It is thought that stem cells hold promise for use in future therapeutics. One such application is tissue engineering (TE) which aims to repair or replace diseased or damaged organs in vitro. Successful applications of TE, where the tissue is replaced and is functional, could improve a patientsâ quality of life. Mesenchymal stem cells (MSCs) are a form of adult stem cell that are a precursor for fat, cartilage and bone cells. Bone is the second most transplanted tissue after blood therefore, enabling TE strategies through provision of high quality bone cells to facilitate bone repair would be beneficial. As MSCs are a precursor to bone, their use is attractive. Additionally, their proliferative potential and immunoregulatory properties make MSCs an ideal candidate cell for TE. MSCs require behavioural cues in vitro that direct phenotype in a targeted way. One method to direct stem cell behaviour is to utilise materials engineering. Static materials (examples include topography, chemistry and stiffness) have been employed but research has now moved towards stimuli responsive technologies to provide dual functionalities for culture and that emulate the properties of the stem cell niche.
It is the intention of the work described in this thesis to utilise an enzyme responsive technology to promote MSC self-renewal and stimulate MSC differentiation to bone. Using solid phase peptide synthesis (SPPS) a biomimetic enzyme responsive material was made with the sequence PEG-GPAGâLRGD tethered to a glass coverslip. Due to enzyme action on the sequence, the PEG cap is removed to create on demand adhesion to the peptide RGD. Further, the surface is designed to be under the control of cell secreted enzymes, rather than in response to enzymes added in by the user.
The cell secreted enzymes that were investigated for this thesis were the matrix metalloproteases (MMPs). Here we confirm that the primary MMP secreted by MSCs was the gelatinase MMP-2 and a peptide sequence was designed to be cleaved by this MMP. It is known that redundancy can occur in MMP families and the role of MMP-9 was also investigated. The results show that MMP-9 is as efficient for surface cleavage, although cell supernatant concentration was 100-fold lower. MMP-2 concentration increased at week 3 specifically in response to peptides and so formed the original hypothesis that cleavage occurred at that time point. However, due to the potency of MMP-9 this may not be the case. Due to the limitations of manual synthesis and availability of materials, there was not enough evidence of MSC self-renewal. Further there was some indication of osteogenesis, specifically in response to the sequence at 4-6 weeks, however this is too long in culture to be therapeutically relevant. It may be better in the future to employ an enzyme responsive surface that can guarantee 100% efficiency of cleavage to ensure a synchronised population of end terminal cells
Interrater reliability of surveillance for ventilator-associated events and pneumonia
OBJECTIVETo compare interrater reliabilities for ventilator-associated event (VAE) surveillance, traditional ventilator-associated pneumonia (VAP) surveillance, and clinical diagnosis of VAP by intensivists.DESIGNA retrospective study nested within a prospective multicenter quality improvement study.SETTINGIntensive care units (ICUs) within 5 hospitals of the Centers for Disease Control and Prevention Epicenters.PATIENTSPatients who underwent mechanical ventilation.METHODSWe selected 150 charts for review, including all VAEs and traditionally defined VAPs identified during the primary study and randomly selected charts of patients without VAEs or VAPs. Each chart was independently reviewed by 2 research assistants (RAs) for VAEs, 2 hospital infection preventionists (IPs) for traditionally defined VAP, and 2 intensivists for any episodes of pulmonary deterioration. We calculated interrater agreement using Îș estimates.RESULTSThe 150 selected episodes spanned 2,500 ventilator days. In total, 93â96 VAEs were identified by RAs; 31â49 VAPs were identified by IPs, and 29â35 VAPs were diagnosed by intensivists. Interrater reliability between RAs for VAEs was high (Îș, 0.71; 95% CI, 0.59â0.81). Agreement between IPs using traditional VAP criteria was slight (Îș, 0.12; 95% CI, â0.05â0.29). Agreement between intensivists was slight regarding episodes of pulmonary deterioration (Îș 0.22; 95% CI, 0.05â0.39) and was fair regarding whether episodes of deterioration were attributable to clinically defined VAP (Îș, 0.34; 95% CI, 0.17â0.51). The clinical correlation between VAE surveillance and intensivistsâ clinical assessments was poor.CONCLUSIONSProspective surveillance using VAE criteria is more reliable than traditional VAP surveillance and clinical VAP diagnosis; the correlation between VAEs and clinically recognized pulmonary deterioration is poor.Infect Control Hosp Epidemiol 2017;38:172â178</jats:sec
Teacher Development Multi-Year Study Series. Evaluation of Australiaâs investment in teacher development in Lao PDR: Interim report 1
The Government of Lao Peopleâs Democratic Republic (Lao PDR) is undertaking significant primary education reforms, supported by the Australian Government\u27s Department of Foreign Affairs and Trade (DFAT) through its flagship Basic Education Quality and Access in Laos program (BEQUAL). The Australian Government has commissioned a study to investigate how the BEQUAL program is making a difference to improving teaching quality and student learning outcomes. This research is part of a multi-year study series undertaken by DFAT\u27s Education Analytics Service to investigate teacher and learning development initiatives in three countries: Lao PDR, Timor-Leste and Vanuatu. In 2019, the new curriculum for Lao language and other subjects was introduced for Grade 1 and is being phased in across all five primary grades. The new curriculum promotes teaching practices that support pedagogies focused on student-centred approaches, active learning, assessment of student learning progress, and a phonics approach to teaching reading. Teachers are being provided with teacher guides and other teaching and learning resources, and receive face-to-face orientation on the new curriculum. In BEQUAL-targeted districts, education support grants are also available to facilitate additional in-service support for teachers and principals. This study has provided the opportunity to investigate teaching quality and student literacy outcomes in Lao PDR over two rounds of data collection, with another planned for October 2022. The Baseline Report captured âstate of playâ information in 2019 prior to major curriculum changes, as well as the onset of the COVID-19 pandemic. This summary provides an overview of findings and recommendations from the second year (2021) of the study, following two years of BEQUAL support for the implementation of the new Grade 1 Lao language curriculum
Report Highlights: Evaluation of Australiaâs investment in teacher development in Lao PDR: Interim report 1
The Government of Lao Peopleâs Democratic Republic (Lao PDR) is undertaking significant primary education reforms, supported by the Australian Governmentâs Department of Foreign Affairs and Trade (DFAT) through its flagship Basic Education Quality and Access in Laos program (BEQUAL). The Australian Government has commissioned a study to investigate how the BEQUAL program is making a difference to improving teaching quality and student learning outcomes. This research is part of a multi-year study series undertaken by DFATâs Education Analytics Service to investigate teacher and learning development initiatives in three countries: Lao PDR, Timor-Leste and Vanuatu
Mesenchymal stem cell fate : applying biomaterials for control of stem cell behavior
The materials pipeline for biomaterials and tissue engineering applications is under continuous development. Specifically, there is great interest in the use of designed materials in the stem cell arena as materials can be used to manipulate the cells providing control of behaviour. This is important as the ability to 'engineer' complexity and subsequent in vitro growth of tissues and organs is a key objective for tissue engineers. This review will describe the nature of the materials strategies, both static and dynamic, and their influence specifically on mesenchymal stem cell fate
Beyond Income: What Else Predicts Very Low Food Security among Children?
We examine characteristics and correlates of households in the United States that are most likely to have children at risk of inadequate nutrition â those that report very low food security (VLFS) among their children. Using 11 years of the Current Population Survey, plus data from the National Health and Nutrition Examination Survey and American Time Use Survey, we describe these households in great detail with the goal of trying to understand how these households differ from households without such severe food insecurity. While household income certainly plays an important role in determining VLFS among children, we find that even after flexibly controlling for income-to-poverty rates some household characteristics and patterns of program participation have important additional explanatory power. Finally, our examination of the NHANES and ATUS data suggests an important role for both mental and physical health in determining the food security status of children
New Evidence on Why Children\u27s Food Security Varies Across Households with Similar Incomes
This project examines why very low food security status among children is different across households with very similar measured resources. Controlling for measures of income-to-needs, we examine whether elements in the!environment, household characteristics, or behaviors are systematically correlated with VLFS among children. We use different measures of income-to-needs, including those averaged across years to capture âpermanentâ income (or to average out measurement error) and measures that include income after taxes and transfers. Our analysis uses the Current Population Survey (across many years, matched December to March), the American Time Use Survey (matched to the December CPS), the National Health and Nutrition Examination Surveys (1999-2010), and the Panel Study of Income Dynamics. We find that, no matter how we control for income-to-needs, certain characteristics appear to be systematically correlated with VLFS among children. In particular, mental and physical disabilities of the household head are strongly correlated with!VLFS among children. The presence of teenage children, holding other aspects of household size and composition constant, predict VLFS among children,suggesting that larger children require more food. Finally, participating in transfer programs is correlated with VLFS among children, suggesting that these households are in the âsystem.â These patterns suggest pathways for future research and future policy actions to address VLFS among children
Teacher Development Multi-Year Study Series: Evaluation of Australiaâs Investment in Teacher Development in Lao PDR: Baseline Report
This report constitutes the Baseline Report of the multi-year study of the Australian Government Department of Foreign Affairs and Tradeâs (DFAT) investment in teacher development in Lao PDR through the Basic Education Quality and Access in Laos program (BEQUAL). This Lao PDR study is part of a three-country multi-year study series on teacher development, in response to DFATâs Office of Development Effectivenessâ 2015 Investing in Teachers report. This study is framed within the context of Lao PDRâs staged introduction of a new primary education curriculum, and accompanying in-service teacher professional development support. The overall aim of this study is to investigate the teacher professional development component to answer the question: to what extent does BEQUAL support improve teaching quality and student literacy in Lao PDR
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