1,828 research outputs found

    Forecasting in South African pelagic fisheries management: The use of expert and decision support systems

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    Understanding long-term variability of pelagic fish populations is important in developing forecasting strategies for fisheries management and planning. However, many current fisheries models have only shortterm datasets available, whereas those of suitable duration often lack reliability. As resources are placed under increasing pressure, all available information should be used to assist management. Two simple rulebased deterministic modelling approaches are described, which use semi-quantitative and qualitative rules to relate recruitment success of South African anchovy Engraulis capensis to physical and biological indices. The first model relates recruitment success to indices of wind and sea surface temperature by way of a rulebased decision support system. In the second model, significant environmental and biological factors were identified and related to anchovy recruitment by way of an expert system approach. These two approaches are evaluated and compared. It is suggested that these types of models, when satisfactorily validated, have great potential in supporting the future management of the South African anchovy fishery in the dynamic  environment of the Benguela Current

    The effect of sea temperature and food availability on the spawning success of Cape Anchovy engraulis capensis in the Southern Benguela

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    Data on the thermal structure, copepod biomass and production, and total number of eggs of the Cape anchovy Engraulis capensis were obtained from monthly surveys during the periods August 1993 – March1994 and September 1994 – March 1995 on the western Agulhas Bank and off the South-Western Cape, South Africa. Previous work suggested that anchovy spawn on the western Agulhas Bank in temperaturesbetween 16 and 19°C, where they feed predominantly on copepods. This study shows that the western Bank is a more suitable spawning area for anchovy, having greater thermal stability, a larger area of 16–19°Cwater and a more consistent food environment than off the South-Western Cape. Also, copepod production on the western Bank was highest in 16–19°C water. To identify factors controlling the area of this watermass, a cluster analysis was used on a suite of hydrographic variables. Three periods were identified: winter (August-September), spring (October-December) and summer (January-March), reflecting changes in theextent of the 16–19°C water and anchovy spawning, both of which peaked during spring. Spring was further characterized by infrequent surface upwelling. During summer, upwelling frequently reached the surface andthe upwelling front migrated offshore, constricting the area of 16–19°C water. It is hypothesized that spawning success in anchovy is dependent upon the extent of suitable spawning habitat, both spatially (16–19°Cwater) and temporally (spring). To put this concept into a predictive framework, the number of anchovy eggs was regressed against the area of 16–19°C water; a significant, positive relationship (p < 0.001, r2 = 0.56, n = 17) was found. An implication of the hypothesis is that the duration of spawning may be important to recruitment

    Elevated 5hmC levels characterize DNA of the cerebellum in Parkinson’s disease

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    5-methylcytosine and the oxidation product 5-hydroxymethylcytosine are two prominent epigenetic variants of the cytosine base in nuclear DNA of mammalian brains. We measured levels of 5-methylcytosine and 5-hydroxymethylcytosine by enzyme-linked immunosorbent assay in DNA from post-mortem cerebella of individuals with Parkinson’s disease and age-matched controls. 5-methylcytosine levels showed no significant differences between Parkinson’s disease and control DNA sample sets. In contrast, median 5-hydroxymethylcytosine levels were almost twice as high (p < 0.001) in both male and female Parkinson’s disease individuals compared with controls. The distinct epigenetic profile identified in cerebellar DNA of Parkinson’s disease patients raises the question whether elevated 5-hydroxymethylcytosine levels are a driver or a consequence of Parkinson’s disease

    Analysis of factors influencing the ultrasonic fetal weight estimation

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    Objective: The aim of our study was the evaluation of sonographic fetal weight estimation taking into consideration 9 of the most important factors of influence on the precision of the estimation. Methods: We analyzed 820 singleton pregnancies from 22 to 42 weeks of gestational age. We evaluated 9 different factors that potentially influence the precision of sonographic weight estimation ( time interval between estimation and delivery, experts vs. less experienced investigator, fetal gender, gestational age, fetal weight, maternal BMI, amniotic fluid index, presentation of the fetus, location of the placenta). Finally, we compared the results of the fetal weight estimation of the fetuses with poor scanning conditions to those presenting good scanning conditions. Results: Of the 9 evaluated factors that may influence accuracy of fetal weight estimation, only a short interval between sonographic weight estimation and delivery (0-7 vs. 8-14 days) had a statistically significant impact. Conclusion: Of all known factors of influence, only a time interval of more than 7 days between estimation and delivery had a negative impact on the estimation

    Reducing unscheduled hospital care for adults with diabetes following a hypoglycaemic event: which community-based interventions are most effective? A systematic review

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    AIM: To determine which community-based interventions are most effective at reducing unscheduled hospital care for hypoglycaemic events in adults with diabetes. METHODS: Medline Ovid, CINAHL Plus and ProQuest Health and Medical Collection were searched using both key search terms and medical subject heading terms (MeSH) to identify potentially relevant studies. Eligible studies were those that involved a community-based intervention to reduce unscheduled admissions in adults with diabetes. Papers were initially screened by the primary researcher and then a secondary reviewer. Relevant data were then extracted from papers that met the inclusion criteria. RESULTS: The search produced 2226 results, with 1360 duplicates. Of the remaining 866 papers, 198 were deemed appropriate based on titles, 90 were excluded following abstract review. A total of 108 full papers were screened with 19 full papers included in the review. The sample size of the 19 papers ranged from n = 25 to n = 104,000. The average ages within the studies ranged from 41 to 74 years with females comprising 57% of the participants. The following community-based interventions were identified that explored reducing unscheduled hospital care in people with diabetes; telemedicine, education, integrated care pathways, enhanced primary care and care management teams. CONCLUSIONS: This systematic review shows that a range of community-based interventions, requiring different levels of infrastructure, are effective in reducing unscheduled hospital care for hypoglycaemia in people with diabetes. Investment in effective community-based interventions such as integrated care and patient education must be a priority to shift the balance of care from secondary to primary care, thereby reducing hospital admissions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40200-021-00817-z

    The TCF7L2 locus and type 1 diabetes

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    <p>Abstract</p> <p>Background</p> <p><it>TCF7L2 </it>belongs to a subfamily of TCF7-like HMG box-containing transcription factors, and maps to human chromosome 10q25.3. A recent study identified genetic association of type 2 diabetes (T2D) with this gene, correlated with diminished insulin secretion. This study aimed to investigate the possibility of genetic association between <it>TCF7L2 </it>and type 1 diabetes (T1D).</p> <p>Methods</p> <p>The SNP most significantly associated with T2D, rs7903146, was genotyped in 886 T1D nuclear family trios with ethnic backgrounds of mixed European descent.</p> <p>Results</p> <p>This study found no T1D association with, and no age-of-onset effect from rs7903146.</p> <p>Conclusion</p> <p>This study suggests that a T2D mechanism mediated by <it>TCF7L2 </it>does not participate in the etiology of T1D.</p

    Identification of 24 new microsatellite loci in the sweat bee Lasioglossum malachurum (Hymenoptera: Halictidae)

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    OBJECTIVE: The objective here is to identify highly polymorphic microsatellite loci for the Palaearctic sweat bee Lasioglossum malachurum. Sweat bees (Hymenoptera: Halictidae) are widespread pollinators that exhibit an unusually large range of social behaviours from non-social, where each female nests alone, to eusocial, where a single queen reproduces while the other members of the colony help to rear her offspring. They thus represent excellent models for understanding social evolution. RESULTS: 24 new microsatellite loci were successfully optimized. When amplified across 23-40 unrelated females, the number of alleles per locus ranged from 3 to 17 and the observed heterozygosities 0.45 to 0.95. Only one locus showed evidence of significant deviation from Hardy-Weinberg equilibrium. No evidence of linkage disequilibrium was found. These 24 loci will enable researchers to gain greater understanding of colony relationships within this species, an important model for the study of eusociality. Furthermore, 22 of the same loci were also successfully amplified in L. calceatum, suggesting that these loci may be useful for investigating the ecology and evolution of sweat bees in general

    Attachment styles and personal growth following romantic breakups: The mediating roles of distress, rumination, and tendency to rebound

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    © 2013 Marshall et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.The purpose of this research was to examine the associations of attachment anxiety and avoidance with personal growth following relationship dissolution, and to test breakup distress, rumination, and tendency to rebound with new partners as mediators of these associations. Study 1 (N = 411) and Study 2 (N = 465) measured attachment style, breakup distress, and personal growth; Study 2 additionally measured ruminative reflection, brooding, and proclivity to rebound with new partners. Structural equation modelling revealed in both studies that anxiety was indirectly associated with greater personal growth through heightened breakup distress, whereas avoidance was indirectly associated with lower personal growth through inhibited breakup distress. Study 2 further showed that the positive association of breakup distress with personal growth was accounted for by enhanced reflection and brooding, and that anxious individuals’ greater personal growth was also explained by their proclivity to rebound. These findings suggest that anxious individuals’ hyperactivated breakup distress may act as a catalyst for personal growth by promoting the cognitive processing of breakup-related thoughts and emotions, whereas avoidant individuals’ deactivated distress may inhibit personal growth by suppressing this cognitive work

    FTO gene SNPs associated with extreme obesity in cases, controls and extremely discordant sister pairs

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    <p>Abstract</p> <p>Background</p> <p>FTO is a gene located in chromosome region 16q12.2. Recently two studies have found associations of several single nucleotide polymorphisms (SNPs) in FTO with body mass index (BMI) and obesity, particularly rs1421085, rs17817449, and rs9939609.</p> <p>Methods</p> <p>We examined these three SNPs in 583 extremely obese women with current BMI greater than 35 kg/m<sup>2 </sup>and lifetime BMI greater than 40 kg/m<sup>2</sup>, and 544 controls who were currently normal weight (BMI<25 kg/m<sup>2</sup>) and had never been overweight during their lifetimes.</p> <p>Results</p> <p>We detected highly significant associations of obesity with alleles in all three SNPs (p < 10<sup>-9</sup>). The strongest association was with rs1421085 (p = 3.04 × 10<sup>-10</sup>, OR = 1.75, CI = 1.47–2.08). A subset of 99 cases had extremely discordant sisters with BMI<25 kg/m<sup>2</sup>. The discordant sisters differed in allele and genotype frequencies in parallel with the overall case and control sample. The strongest association was with rs17817449 (z = 3.57, p = 3.6 × 10<sup>-4</sup>).</p> <p>Conclusion</p> <p>These results suggest common variability in FTO is associated with increased obesity risk or resistance and may in part account for differences between closely related individuals.</p
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