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Innovation is something that many governments strive to support, in both the private and public sectors. By bridging the two sectors and creating novel partnerships, public sector expenditure can be reduced

Escapement of the Cape rock lobster (Jasus lalandii ) through the mesh and entrance of commercial traps

Metal-framed traps covered with polyethylene mesh used in the fishery for the South African Cape rock lobster (Jasus lalandii) incidentally capture large numbers of undersize (<75 mm CL) specimens. Air-exposure, handling, and release procedures affect captured rock lobsters and reduce the productivity of the stock, which is heavily fished. Optimally, traps should retain legalsize rock lobsters and allow sublegal animals to escape before traps are hauled. Escapement, based on lobster morphometric measurements, through meshes of 62 mm, 75 mm, and 100 mm was investigated theoretically under controlled conditions in an aquarium, and during field trials. SELECT models were used to model escapement, wherever appropriate. Size-selectivity curves based on the logistic model fitted the aquarium and field data better than asymmetrical Richards curves. The lobster length at 50% retention (L50) on the escapement curve for 100-mm mesh in the aquarium (75.5 mm CL) approximated the minimum legal size (75 mm CL); however estimates of L50 increased to 77.4 mm in field trials where trapentrances were sealed, and to 82.2 mm where trap-entrances were open. Therfore, rock lobsters that cannot escape through the mesh of sealed field traps do so through the trap entrance of open traps. By contrast, the wider selection range and lower L25 of field, compared to aquarium, trials (SR = 8.2 mm vs. 2.6 mm; L25 =73.4 mm vs. 74.1 mm), indicate that small lobsters that should be able to escape from 100-mm mesh traps do not always do so. Escapement from 62-mm mesh traps with open entrance funnels increased by 40−60% over sealed traps. The findings of this study with a known size distribution, are related to those of a recent indirect (comparative) study for the same species, and implications for trap surveys, commercial catch rates, and ghost fishing are discussed

Do fluctuations in the somatic growth rate of rock lobster (Jasus lalandii) encompass all size classes? A re-assessment of juvenile growth

Catch rates in the South African rock lobster (Jasus lalandii) fishery declined after 1989 in response to reduced adult somatic growth rates and a consequent reduction in recruitment to the fishable population. Although spatial and temporal trends in adult growth are well described, little is known about how juvenile growth rates have been affected. In our study, growth rates of juvenile rock lobster on Cape Town harbor wall were compared with those recorded at the same site more than 25 years prior to our study, and with those on a nearby natural nursery reef. We found that indices of somatic growth measured during 1996–97 at the harbor wall had declined significantly since 1971–72. Furthermore, growth was slower among juvenile J. lalandii at the harbor wall than those at the natural nursery reef. These results suggest that growth rates of juvenile and adult J. lalandii exhibit similar types of spatiotemporal patterns. Thus, the recent coastwide decline in adult somatic growth rates might also encompass smaller size classes

Global warming is causing a more pronounced dip in marine species richness around the equator

The latitudinal gradient in species richness, with more species in the tropics and richness declining with latitude, is widely known and has been assumed to be stable over recent centuries. We analyzed data on 48,661 marine animal species since 1955, accounting for sampling variation, to assess whether the global latitudinal gradient in species richness is being impacted by climate change. We confirm recent studies that show a slight dip in species richness at the equator. Moreover, richness across latitudinal bands was sensitive to temperature, reaching a plateau or declining above a mean annual sea surface temperature of 20 °C for most taxa. In response, since the 1970s, species richness has declined at the equator relative to an increase at midlatitudes and has shifted north in the northern hemisphere, particularly among pelagic species. This pattern is consistent with the hypothesis that climate change is impacting the latitudinal gradient in marine biodiversity at a global scale. The intensification of the dip in species richness at the equator, especially for pelagic species, suggests that it is already too warm there for some species to survive.acceptedVersio

Comparing deployment experiences of South African National Defence Force personnel during peace support missions: Sudan vs Democratic Republic of Congo

The South African National Defence Force (SANDF) has operational responsibilities in Africa regarding peace support operations. These deployments are the bread and butter of the SANDF and members are therefore frequently deployed for extended periods. These deployments are unique environments with taxing circumstances, which place various psychological demands on the soldier. The psychological impact of these demands originates not only from combat and the consequent clinical effect thereof, but also from organisational factors and the contribution of family stressors. The study reported here endeavoured to examine the positive and negative subjective deployment experiences of soldiers in two different mission areas. The data are compared and further utilised to provide a framework of two proposed matrices, namely booster and stressor matrices, which may affect the optimal psychological functioning of soldiers. The study adopted a survey design utilising qualitative data focusing on retrospective data. The data stems from the Psychological Demobilisation Questionnaire developed by psychologists in the SANDF and amended by the authors. Data were collected from both combat service support and combat forces, from two different missions in different countries, both missions were one year in duration. Data revealed both positive and negative experiences correlating with the context of operations. These themes were categorised in terms of the sphere of functioning (organisational, family and clinical) from the deployment experience. The booster and stressor matrices provide a practical and accessible framework to military commanders on how to ‘boost’ or mitigate some of the experiences of their deployed force, as the commanders play a key role in the deployed soldier’s experience and the impact of such experiences in the theatre of operation

Spatio-Temporal Variation in Growth Performance and Condition of the Winged Pearl Oyster Pteria penguin

Environmental conditions can strongly influence the growth performance of pearl oysters and affect pearl farm production schedules. Growth and condition index (CI) of two age cohorts of Pteria penguin were measured for 13 months to investigate differences in growth performance between four culture sites within the northern (Vava’u) and southern (Tongatapu) island groups of the Kingdom of Tonga. Environmental conditions were also measured at culture sites and used to explore potential effects on oyster growth and condition. Between island groups, growth performance of P. penguin was superior at northern sites and was most strongly related to higher water temperatures at these sites. Within the southern island group, growth performance varied significantly between sites and may be driven by differences in wave energy. Monthly growth rates (GM) of P. penguin also showed significant temporal variation related to age and environmental conditions. This study demonstrated significant variation in the growth performance of P. penguin at latitudinal and local scales and suggests that in oligotrophic marine environments with minimal terrestrial inputs, such as Tonga, water temperature and wave exposure may be the primary environmental conditions influencing the growth performance of P. penguin. This study therefore recommends that optimal culture sites for P. penguin in Tonga are characterized primarily by warmer water temperatures (25–30°C) and low wave exposure (2 day–1). Culture of P. penguin at sites with more suitable environmental conditions enables pearl production to begin up to 34.2 % (6.5 months) earlier than at less-suitable sites and this may greatly influence mabé pearl farm profitability and feasibility

Spatio-Temporal Variation in Growth Performance and Condition of the Winged Pearl Oyster Pteria penguin

Environmental conditions can strongly influence the growth performance of pearl oysters and affect pearl farm production schedules. Growth and condition index (CI) of two age cohorts of Pteria penguin were measured for 13 months to investigate differences in growth performance between four culture sites within the northern (Vava’u) and southern (Tongatapu) island groups of the Kingdom of Tonga. Environmental conditions were also measured at culture sites and used to explore potential effects on oyster growth and condition. Between island groups, growth performance of P. penguin was superior at northern sites and was most strongly related to higher water temperatures at these sites. Within the southern island group, growth performance varied significantly between sites and may be driven by differences in wave energy. Monthly growth rates (GM) of P. penguin also showed significant temporal variation related to age and environmental conditions. This study demonstrated significant variation in the growth performance of P. penguin at latitudinal and local scales and suggests that in oligotrophic marine environments with minimal terrestrial inputs, such as Tonga, water temperature and wave exposure may be the primary environmental conditions influencing the growth performance of P. penguin. This study therefore recommends that optimal culture sites for P. penguin in Tonga are characterized primarily by warmer water temperatures (25–30°C) and low wave exposure (<15 joules m2 day–1). Culture of P. penguin at sites with more suitable environmental conditions enables pearl production to begin up to 34.2 % (6.5 months) earlier than at less-suitable sites and this may greatly influence mabé pearl farm profitability and feasibility

Retinoblastoma outcome at a single institution in South Africa

Introduction. Retinoblastoma (RB) is the most common eye cancer in children. Early detection is necessary for cure.Objective. To compare stage and outcome of children with RB treated at Kalafong Hospital, Pretoria, South Africa (SA), during two time periods (1993 - 2000 and 2001 - 2008, after outreach interventions in 2000 and introduction of compulsory community service for doctors in 1998).Methods. Data collected included demography (age, gender, date of birth), stage and treatment received. The main outcome measure was disease-free survival and the study end-point was 60 months after diagnosis.Results. There were 51 patients during the time period 1993 - 2000 (group 1) and 73 during 2001 - 2008 (group 2), with median ages of 32 and 26 months, respectively (marginally significantly younger in group 2; p=0.046). In group 1, the majority (57%) presented with advanced disease (stages III and IV), a decline in this proportion in group 2 (40%) indicating a downward but not significant trend (p=0.075). Bilateral disease was diagnosed in 22% of patients in group 1 and 33% in group 2. Overall survival was 33% and 43% for groups 1 and 2, respectively. Excluding absconding patients, event-free survival was 50% in group 1, improving to 68% in group 2 (not statistically significant; p=0.18). Fewer patients needed radiotherapy during the second period (statistically significant; p=0.04), probably because of less advanced disease.Conclusion. Poor outcome is probably a result of late diagnosis. It is important to implement a strategy that will ensure early diagnosis and optimal management of RB in SA

Hypercalcaemic multicentric lymphoma in a dog presenting as clitoromegaly

Clitoromegaly is a clinical manifestation of various local and systemic conditions in all species. The external genitalia are a very rare site of primary or metastatic lymphoma in canines, with only one previously-reported case in a dog and only sparse reports in the medical literature. Lymphoma is also very rare in dogs less than four years of age. This account reports on a T-cell multicentric lymphoma in a 16-month-old Basset hound presented primarily for clitoromegaly. The patient survived for 68 days with cyclophosphamide-vincristine-prednisolone therapy. The causes of clitoromegaly in all species, including humans, are tabulated with references.The Faculty of Veterinary Science, University of Pretoria.http://www.jsava.co.zaam2014mn201