48 research outputs found
Strategic review of enhancements and culture-based fisheries
Enhancements are interventions in the life cycle of common-pool aquatic resources. Enhancement technologies include culture-based fisheries, habitat modifications, fertilization, feeding and elimination of predators/competitors. Enhancements are estimated to yield about two million mt per year, mostly from culture-based fisheries in fresh waters where they account for some 20 percent of capture, or 10 percent of combined capture and culture production. Marine enhancements are still at an experimental stage, but some have reached commercial production. Enhancements use limited external feed and energy inputs, and can provide very high returns for labour and capital input. Moreover, enhancement initiatives can facilitate institutional change and a more active management of aquatic resources, leading to increased productivity, conservation and wider social benefits. Enhancements may help to maintain population abundance, community structure and ecosystem functioning in the face of heavy exploitation and/or environmental degradation. Negative environmental impacts may arise from ecological and genetic interactions between enhanced and wild stocks. Many enhancements have not realised their full potential because of a failure to address specific institutional, technological, management and research requirements emanating from two key characteristics. Firstly, enhancement involves investment in common-pool resources and can only be sustained under institutional arrangements that allow regulation of use and a flow of benefits to those who bear the costs of enhancement. Secondly, interventions are limited to certain aspects of the life cycle of stocks, and outcomes are strongly dependent on natural conditions beyond management control. Hence, management must be adapted to local conditions to be effective, and certain conditions may preclude successful enhancement altogether. Governments have a major role to play in facilitating enhancement initiatives through the establishment of conducive institutional arrangements, appropriate research support, and the management of environmental and other impacts on and from enhancements.<br /
Coastline complexity: a parameter for functional classification of coastal environments
Changes in Plasma Volatile Fatty Acids in Response to Weaning and Feed Intake in Young Calves
Effect of age, sex and gender on pain sensitivity: A narrative review
© 2017 Eltumi And Tashani. Introduction: An increasing body of literature on sex and gender differences in pain sensitivity has been accumulated in recent years. There is also evidence from epidemiological research that painful conditions are more prevalent in older people. The aim of this narrative review is to critically appraise the relevant literature investigating the presence of age and sex differences in clinical and experimental pain conditions. Methods: A scoping search of the literature identifying relevant peer reviewed articles was conducted on May 2016. Information and evidence from the key articles were narratively described and data was quantitatively synthesised to identify gaps of knowledge in the research literature concerning age and sex differences in pain responses. Results: This critical appraisal of the literature suggests that the results of the experimental and clinical studies regarding age and sex differences in pain contain some contradictions as far as age differences in pain are concerned. While data from the clinical studies are more consistent and seem to point towards the fact that chronic pain prevalence increases in the elderly findings from the experimental studies on the other hand were inconsistent, with pain threshold increasing with age in some studies and decreasing with age in others. Conclusion: There is a need for further research using the latest advanced quantitative sensory testing protocols to measure the function of small nerve fibres that are involved in nociception and pain sensitivity across the human life span. Implications: Findings from these studies should feed into and inform evidence emerging from other types of studies (e.g. brain imaging technique and psychometrics) suggesting that pain in the older humans may have unique characteristics that affect how old patients respond to intervention
An experimental investigation of the effect of age and sex/gender on pain sensitivity in healthy human participants
© 2018 El-Tumi et al. Background: Ageing is associated with alterations of the structure and function of somatosensory tissue that can impact on pain perception. The aim of this study was to investigate the relationship between age and pain sensitivity responses to noxious thermal and mechanical stimuli in healthy adults. Methods: 56 unpaid volunteers (28 women) aged between 20 and 55 years were categorised according to age into one of seven possible groups. The following measurements were taken: thermal detection thresholds, heat pain threshold and tolerance using a TSA-II NeuroSensory Analyzer; pressure pain threshold using a handheld electronic pressure algometer; and cold pressor pain threshold, tolerance, intensity and unpleasantness. Results: There was a positive correlation between heat pain tolerance and age (r = 0.228, P = 0.046), but no statistically significant differences between age groups for cold or warm detection thresholds, or heat pain threshold or tolerance. Forward regression found increasing age to be a predictor of increased pressure pain threshold (B = 0.378, P = 0.002), and sex/gender to be a predictor of cold pressor pain tolerance, with women having lower tolerance than men (B =-0.332, P = 0.006). Conclusion: The findings of this experimental study provide further evidence that pressure pain threshold increases with age and that women have lower thresholds and tolerances to innocuous and noxious thermal stimuli. Significance: The findings demonstrate that variations in pain sensitivity response to experimental stimuli in adults vary according to stimulus modality, age and sex and gender
Alojamento do granito Lavras e a mineralização aurÃfera durante evolução de centro vulcano-plutônico pós-colisional, oeste do Escudo Sul-riograndense: dados geofÃsicos e estruturais
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Restocking and stock enhancement of coastal fisheries: Potential, problems and progress
The demand for fish is expected to rise substantially by 2020. Although aquaculture must provide much of the additional fish, it remains to be seen whether restored or enhanced capture fisheries can also help fill the projected gap in supply. The key challenges for capture fisheries involve reducing fishing effort, removing excess fishing capacity and building the institutional arrangements needed to restore spawning biomass to more productive levels, and to reverse degradation of the supporting habitats. Two interventions, based largely on hatchery technology, have the potential to reduce the time needed to rebuild some severely over-exploited fisheries, or improve the productivity of other 'healthy' fisheries. These interventions are 'restocking', which involves releasing cultured juveniles to restore spawning biomass to levels where the fishery can once again support regular harvests, and 'stock enhancement', which involves release of cultured juveniles to overcome recruitment limitation. However, despite the potential of these interventions, few restocking and stock enhancement programmes have met expectations. The main problems have been a pre-occupation with bio-technical research at the expense of objective analysis of the need for the intervention, and failure to integrate the technology within an appropriate management scheme that has the participation and understanding of the users. The papers presented at the Special Symposium on this subject at the Seventh Asian Fisheries Forum provide a series of valuable lessons to guide objective assessment of the potential for restocking and stock enhancement. They also show how to implement these interventions responsibly and effectively where they are deemed to add value to other forms of management. Above all, these studies demonstrate that restocking and stock enhancement programmes are applied in complex human-environment systems, involving dynamic interactions between the resource, the technical intervention and the people who use it