490 research outputs found
Environmental challenges to operationalisation of South African rainfall enhancement
Most of the atmospheric moisture in systems moving across South Africa leaves the sub-continent as the weather systems move
out over the ocean, only a tenth of it falls on the landmass as rain. An increase in the efficiency of the atmospheric moisture delivery
system by means of rainfall enhancement is therefore an attractive concept. Rainfall enhancement functions by either providing
additional Cloud Condensation Nuclei or Ice forming Nuclei that will beneficially influence the precipitation formation process,
improving the efficiency of moisture to rainfall conversion.
Systematic South African research into rainfall enhancement started in the 1970s. The South African Rainfall Enhancement
Programme (SAREP), initiated in the late 1990\'s, is the most recent in a series of studies and was the first semi-operational rainfall
enhancement project to occur in South Africa as a response to drought conditions. In a recent study (DWAF, 2004 in prep) to finalise
SAREP and provide guidance on operationalising rainfall enhancement, it was recommended that environmental impact
assessment must be undertaken before this technology is implemented further.
Rainfall enhancement falls specifically within the jurisdiction of the National Water Act (NWA) and the National
Environmental Management Act (NEMA). A licence to undertake rainfall enhancement activities is required from the Minister of Water Affairs and Forestry after an appropriate environmental impact assessment has been undertaken to inform his decision. This paper proposes an approach to fulfil the legal requirements for operationalising future rainfall enhancement. The interaction between the science of rainfall enhancement and the ability of scientific disciplines to determine relevant environmental impacts, to appropriately inform the decision-making process, is specifically highlighted. The data requirements identified by scientists during the study varies in duration and resource needs and does not differentiate between ongoing scientific research and the requisite information required for informed decision making. This paper contemplates an approach which provides for holistic and co-ordinated investigation of South African rainfall enhancement into the future. Water SA Vol. 30 (5) 2005: pp.88-9
Editorial
Somatostatin analogues and their clinical applicationLaparoscopic cholecystectom
Cold treatment enhances low-temperature flight performance in false codling moth, Thaumatotibia leucotreta (Lepidoptera: Tortricidae)
1 In sterile insect technique programmes, temperatures experienced by insects during rearing and handling, along with cool temperatures after release, can negatively affect performance and activity levels. Phenotypic plasticity (trait modifications caused by
prior stress exposure) can offset these effects but is poorly understood in many species and traits.
2 We investigated the effects of a cold treatment (2 ∘C for 16 h) on flight performance in adult false codling moth, Thaumatotibia leucotreta. Using diverse methods, flight performance was tested using flight assays in the laboratory and in the field under
varying environmental conditions.
3 The flight performance of T. leucotreta in the laboratory was affected by cold treatment (relative to a 25 ∘C control group), test temperature and their interaction. Field recapture of released moths was significantly affected by the interaction between cold
treatment and environmental conditions.
4 Field recapture counts depended on the ambient temperature upon release. For example, under warmer conditions (>17 ∘C), the recapture count of cold-treated moths was lower than that of the untreated control group, whereas the recapture count of
cold-treated moths at cooler temperatures was significantly higher.
5 Our results suggest a temperature-dependent interaction between acute cold exposure and flight performance in adult T. leucotreta, which may be used to enhance the efficacy of the sterile insect technique under cooler environmental conditions
Deconstructing intercontinental invasion pathway hypotheses of the Mediterranean fruit fly (Ceratitis capitata) using a Bayesian inference approach: are port interceptions and quarantine protocols successfully preventing new invasions?
Aim Knowledge of how effective interceptions and quarantine measures are in preventing new biological invasions is of paramount importance for maintaining ecosystem function in a rapidly changing world. Here, we determine current macrogeographic population structure and routes of invasion of the Mediterranean fruit fly (Ceratitis capitata) using genetic approaches and reconstruct and test invasion pathway hypotheses in a Bayesian framework.
Location Africa, Australia, Greece, Guatemala and Madeira. Methods We sampled 323 C. capitata individuals from 14 locations worldwide and genotyped all individuals for 11 polymorphic microsatellite markers. We calculated measures of genetic diversity and determined population structure. Moreover, we reconstructed and tested eighteen invasion pathway scenarios in a Bayesian framework using ABC modelling. Results We show a decrease in genetic diversity outside the native range (Africa) into the introduced range (Australia, Greece, Guatemala and Madeira). The most likely invasion pathway scenario closely matched the historical
records, with an initial colonization of Europe from Africa and a secondary colonization of Australia from Europe. Moreover, we show an introduction from
Greece to the Americas and, finally, a back introduction into South Africa from Europe.
Main conclusions Given the lack of new introductions into colonized (non-African) locations despite increasing trade, and apart from the initial invasion and establishment of the species outside of Africa, we conclude that quarantine
and interception measures have been largely successful to date
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Interventions to promote patients and families' involvement in adult intensive care settings: a protocol for a mixed-method systematic review.
BACKGROUND: There has been an identified need for greater patient and family member involvement in healthcare. This is particularly relevant in an intensive care unit (ICU), as the family provides a key communicative and practical link between patient and clinician. Family members have been deemed a positive beneficial influence on ICU care and recovery processes, yet they themselves are often emotionally affected after discharge. There has been no standardised evidenced-based approach which explores research on family member involvement and the range and quality of contributions remain unclear. This project will undertake a systematic review to assess the evidence base for interventions designed to promote patient and family member involvement in adult intensive care settings and develop a comprehensive typology of interventions for use by clinicians, patients and carers. METHODS: The following databases will be searched without date restriction: MEDLINE, EMBASE and CINAHL, as well as the Cochrane Central Register of Controlled Trials, Joanna Briggs and Cochrane Libraries. Manual searches of recent back issues of leading ICU and patient experience journals will also be undertaken, as will the reference lists of included studies. Unpublished literature will be sought through grey literature databases, including GreyLit and OpenGrey. All evaluation studies that consider intervention activities to promote patient and family member involvement in adult ICUs will be included; all research designs will be eligible. We will seek to include studies that report on a mixture of relevant outcomes for patients and family members. Abstracts and papers will be independently screened by at least two members of the team to determine their inclusion. Included papers will be assessed for methodological rigour using a standard rating approach, which assesses 'quality of study' and 'quality of information'. Quality assessment will be completed by at least two members of the team. Data on interventions, evaluation methods and outcomes will be collated using a predetermined extraction table. These are likely to be heterogeneous in nature, which will mean that the review will follow a narrative approach to synthesis. DISCUSSION: The review will provide valuable and rigorous insight into the range and quality of interventions available to promote patient and family member involvement in ICU. This is the first step towards addressing the absence of a synthesis of research for this context, and will, in addition, develop a typology of available interventions that will help service users and clinicians make informed decisions about the approaches to patient and family member involvement which they might want to adopt. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (CRD42018086325)
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