19 research outputs found
An exploration of the relationship between leadership styles and the implementation of transformation interventions.
The objective of this research was to determine whether a relationship exists between the way in which subordinates experience their managers’ leadership styles and the influence of such leadership styles on the implementation of transformation interventions. A two-phase triangulated research design was employed where the qualitative phase preceded the quantitative phase. Ninety six (N = 96) respondents from a mining company participated in the survey. Results indicate a statistical and meaningful correlation between Integrated Leadership styles and transformation interventions but no correlation between Directive Leadership and implementation of transformation interventions
Vulnerability of Cape Fold Ecoregion freshwater fishes to climate change and other human impacts
1. Native freshwater fish populations throughout South Africa's Cape Fold Ecoregion (CFE) are in decline as a result of human impacts on aquatic habitats, including the introduction of nonnative
freshwater fishes. Climate change may be further accelerating declines of many species, although this has not yet been studied in the CFE. This situation presents a major conservation challenge that requires assigning management priorities through assessing species in terms of their vulnerability to climate change.
2. One factor hindering reliable vulnerability assessments and the concurrent development of effective conservation strategies is limited knowledge of the biology and population status of many species. This paper reports on a study employing a rapid assessment method used
in the USA, designed to capitalize on available expert knowledge to supplement existing empirical data, to determine the relative vulnerabilities of different species to climate change and other human impacts. Eight local freshwater fish experts conducted vulnerability assessments on 20 native and 17 non‐native freshwater fish species present in the CFE.
3. Results show (1) that native species were generally classified as being more vulnerable to extinction than were non‐native species, (2) that the climate change impacts are expected to increase the vulnerability of most native, and some non‐native, species, (3) that vulnerability
hotspots requiring urgent conservation attention occur in the Olifants‐Doring, upper Berg and upper Breede River catchments in the south west of the region, (4) that in addition to providing guidance for prioritizing management interventions, this study highlights the need for reliable data on the biology and distribution of many CFE freshwater fishes, and (5) that
identification of priority areas for protection should be based on multiple sources of data
Comparative effectiveness of autologous hematopoietic stem cell transplant vs fingolimod, natalizumab, and ocrelizumab in highly active relapsing-remitting multiple sclerosis
Importance: Autologous hematopoietic stem cell transplant (AHSCT) is available for treatment of highly active multiple sclerosis (MS).
Objective: To compare the effectiveness of AHSCT vs fingolimod, natalizumab, and ocrelizumab in relapsing-remitting MS by emulating pairwise trials.
Design, Setting, and Participants: This comparative treatment effectiveness study included 6 specialist MS centers with AHSCT programs and international MSBase registry between 2006 and 2021. The study included patients with relapsing-remitting MS treated with AHSCT, fingolimod, natalizumab, or ocrelizumab with 2 or more years study follow-up including 2 or more disability assessments. Patients were matched on a propensity score derived from clinical and demographic characteristics.
Exposure: AHSCT vs fingolimod, natalizumab, or ocrelizumab.
Main outcomes: Pairwise-censored groups were compared on annualized relapse rates (ARR) and freedom from relapses and 6-month confirmed Expanded Disability Status Scale (EDSS) score worsening and improvement.
Results: Of 4915 individuals, 167 were treated with AHSCT; 2558, fingolimod; 1490, natalizumab; and 700, ocrelizumab. The prematch AHSCT cohort was younger and with greater disability than the fingolimod, natalizumab, and ocrelizumab cohorts; the matched groups were closely aligned. The proportion of women ranged from 65% to 70%, and the mean (SD) age ranged from 35.3 (9.4) to 37.1 (10.6) years. The mean (SD) disease duration ranged from 7.9 (5.6) to 8.7 (5.4) years, EDSS score ranged from 3.5 (1.6) to 3.9 (1.9), and frequency of relapses ranged from 0.77 (0.94) to 0.86 (0.89) in the preceding year. Compared with the fingolimod group (769 [30.0%]), AHSCT (144 [86.2%]) was associated with fewer relapses (ARR: mean [SD], 0.09 [0.30] vs 0.20 [0.44]), similar risk of disability worsening (hazard ratio [HR], 1.70; 95% CI, 0.91-3.17), and higher chance of disability improvement (HR, 2.70; 95% CI, 1.71-4.26) over 5 years. Compared with natalizumab (730 [49.0%]), AHSCT (146 [87.4%]) was associated with marginally lower ARR (mean [SD], 0.08 [0.31] vs 0.10 [0.34]), similar risk of disability worsening (HR, 1.06; 95% CI, 0.54-2.09), and higher chance of disability improvement (HR, 2.68; 95% CI, 1.72-4.18) over 5 years. AHSCT (110 [65.9%]) and ocrelizumab (343 [49.0%]) were associated with similar ARR (mean [SD], 0.09 [0.34] vs 0.06 [0.32]), disability worsening (HR, 1.77; 95% CI, 0.61-5.08), and disability improvement (HR, 1.37; 95% CI, 0.66-2.82) over 3 years. AHSCT-related mortality occurred in 1 of 159 patients (0.6%).
Conclusion: In this study, the association of AHSCT with preventing relapses and facilitating recovery from disability was considerably superior to fingolimod and marginally superior to natalizumab. This study did not find evidence for difference in the effectiveness of AHSCT and ocrelizumab over a shorter available follow-up time
Conservation implications of establishment success of the Critically Endangered Twee River redfin ‘Pseudobarbus’ erubescens (Skelton, 1974) in an artificial impoundment in South Africa
1. This study reports the first known record of breeding of the Critically Endangered Twee River redfin ‘Pseudobarbus’ erubescens in an artificial impoundment. This followed an introduction of 48 individuals into a 10 ha impoundment within the species' native range more than a decade ago.
2. Sampling the impoundment using three fyke nets set overnight yielded 2838 P. erubescens, which included both juveniles and adults capable of spawning. Fork length measurements of a subsample of 250 individuals ranged from 29 to 125 mm with length cohorts indicating multiple
spawning events.
3. This demonstrates that this species can successfully reproduce in lentic environments and suggests that artificial impoundments could be stocked to provide refugia for P. erubescens and other highly threatened small cyprinids while conservation strategies are developed to
mitigate against habitat loss resulting from alien fish invasions, increased human use of water, and from climate change in rivers
Ecosystem responses to the eradication of common carp Cyprinus carpio using rotenone from a reservoir in South Africa
1. The control of invasive alien fish populations using piscicides to alleviate impacts on native biota is a controversial conservation strategy because the collateral impacts on non‐target taxa are not well documented. This article documents the responses of water quality, plankton and macroinvertebrate communities to an eradication of the globally invasive common carp Cyprinus carpio Linnaeus 1758, using the piscicide rotenone in a small South African reservoir. 2. Treated and untreated reservoirs were sampled before and at intervals following rotenone treatment. Sampling endpoints included water quality parameters, plankton, macroinvertebrates and fish. These endpoints were selected to gain an understanding of the ecological impacts of the treatment at various biological levels and to document possible recovery following treatment. 3. The study showed that: (i) the common carp were successfully removed; (ii) water clarity improved following the removal of fish; (iii) invertebrate communities, including macroinvertebrates and large zooplankton, recovered within 6 months of treatment; and (iv) that small zooplankton (i.e. Rotifera) dynamics were complex but rotifer abundances had returned to pre‐treatment levels within 6 months of treatment.4. 4. There was a 56% similarity between the macroinvertebrate assemblages before and 6 months after treatment, showing a substantial turnover in taxa following treatment. The phytoplankton community of the treated reservoir was dominated by blue‐green and green algae prior to the treatment. The blue‐green algal communities were not present 6 months after the treatment, possibly indicating a change in the nutrient status of the reservoir resulting from lower nutrient concentrations in the water column. 5. The phytoplankton community of the reservoir changed from a community typical of eutrophic waters to a community typical of a lower nutrient state. Within each group, there were species changes, but we suggest these are likely to be part of the altered biological interaction dynamics resulting from fish removals, rather than a direct effect of rotenone
Yeast Eicosanoids I. The Distribution and Taxonomic Value of Cellular Fatty Acids and Arachidonic Acid Metabolites in the Dipodascaceae and Related Taxa
Variability of the Mitochondrial Genome and Development of the Primary Progressing form of Multiple Sclerosis
Parâmetros sangüíneos e urinários, no pré e pós parto, de búfalas criadas em sistema exclusivo de pastejo The blood and urinary values in the pre and pos-parturient period of buffaloes, kept on exclusive pasture feeding
Foi avaliada a ocorrência de alterações nas concentrações de glicose sanguínea, proteína plasmática total, hematócrito e presença de corpos cetônicos na urina de oito búfalas leiteiras da raça Murrah, com idade variando entre 5 e 10 anos, com no mínimo duas lactações, clinicamente sadias, desde 60 dias antes até 60 dias pós-parto. As concentrações médias de glicose sangüínea e o valor médio do hematócrito diminuíram significativamente no pós-parto (p<0,05). As concentrações de proteína plasmática total não sofreram variações significativas do pré para o pós-parto. No período pré-parto os corpos cetônicos só foram detectados na urina de uma búfala; entretanto, a partir do 32º dia de lactação foram detectados em todos os animais. Houve uma relação direta entre a coloração da urina positiva para o teste de Rothera e as concentrações de glicose sangüínea. Pode-se concluir que na fase inicial da lactação as búfalas utilizadas sofreram um déficit energético, caracterizado pela diminuição nas concentrações sangüíneas de glicose e presença de corpos cetônicos na urina, e que a lactação causou um declínio progressivo no hematócrito, enquanto que as concentrações da proteína plasmática total não sofreram variações do pré para o pós-parto.<br>Eight lactating buffaloes of the Murrah breed were used from 60 days before up to 60 days after calving, in order to evaluate alterations in the concentration of blood glucose, total plasmatic protein, haematocrit and the presence of ketonic bodies in the urine. The 5 to 10- year old buffaloes were clinically healthy and had had at least two lactations. During the experimental period the animals were maintained on Brachiaria brizantha pasture and supplemented with a mineral mixture and water.The media concentrations of blood glucose and the media values of the haematocrit diminished significantly after calving (p<0,05). The concentrations of total plasmatic protein did not show significant variation during the pre and post-calving period. The ketonic bodies in the pre-calving period were only detected in the urine of one buffaloe, but after the 32nd day of lactation ketonic bodies were detected in all animals. There was a direct relationship between the color of the urine positive by the Rothera test and blood glucose concentrations. It can be concluded that at the beginning of lactation the buffaloes had an energetic deficit, characterized by a decline of blood glucose concentrations and the presence of ketonic bodies in the urine, and that lactation caused a progressive decline of the hematocrit, but that the concentration of total plasmatic protein did not vary during the pre and post-calving period