297 resultados para breeding population
Resumo:
Neonate Lepidoptera are confronted with the daunting task of establishing themselves on a food plant. The factors relevant to this process need to be considered at spatial and temporal scales relevant to the larva and not the investigator. Neonates have to cope with an array of plant surface characters as well as internal characters once the integument is ruptured. These characters, as well as microclimatic conditions, vary within and between plant modules and interact with larval feeding requirements, strongly affecting movement behavior, which may be extensive even for such small organisms. In addition to these factors, there is an array of predators, pathogens, and parasitoids with which first instars must contend. Not surprisingly, mortality in neonates is high but can vary widely. Experimental and manipulative studies, as well as detailed observations of the animal, are vital if the subtle interaction of factors responsible for this high and variable mortality are to be understood. These studies are essential for an understanding of theories linking female oviposition behavior with larval survival, plant defense theory, and population dynamics, as well as modern crop resistance breeding programs.
Resumo:
Skipjack (SJT) (Katsuwonus pelamis) is a medium sized, pelagic, highly dispersive tuna species that occurs widely across tropical and subtropical waters. SJT constitute the largest tuna fishery in the Indian Ocean, and are currently managed as a single stock. Patterns of genetic variation in a mtDNA gene and 6 microsatellite loci were examined to test for stock structure in the northwestern Indian Ocean. 324 individuals were sampled from five major fishing grounds around Sri Lanka, and single sites in the Maldive Islands and the Laccadive Islands. Phylogenetic reconstruction of mtDNA revealed two coexisting divergent clades in the region. AMOVA (Analysis of Molecular Variance) of mtDNA data revealed significant genetic differentiation among sites (ΦST = 0.2029, P < 0.0001), also supported by SAMOVA results. AMOVA of microsatellite data also showed significant differentiation among most sampled sites (FST = 0.0256, P<0.001) consistent with the mtDNA pattern. STRUCTURE analysis of the microsatellite data revealed two differentiated stocks. While the both two marker types examined identified two genetic groups, microsatellite analysis indicates that the sampled SJT are likely to represent individuals sourced from discrete breeding grounds that are mixed in feeding grounds in Sri Lankan waters.
Resumo:
Introduction Polybrominated diphenyl ethers (PBDEs) are considered to be a cost effective and efficient way to reduce the possibility of product ignition and inhibit the spread of fire, thereby limiting harm caused by fires. PBDEs are incorporated into a wide variety of manufactured products and are now considered an ubiquitous contaminant found worldwide in biological and environmental samples1 . In comparison to “traditional” persistent organic pollutants (POPs), the exposure modes of PBDEs in humans are less well defined, although dietary sources, inhalation (air/particulate matter) and dust ingestion have been reported 2-4. Limited investigations of population specific factors such as age or gender and PBDE concentrations report: no conclusive correlation by age in adults; higher concentrations in children ; similar concentrations in maternal and cord blood; and no gender differences. After preliminary findings of higher PBDE concentrations in children than in adults in Australia11 we sought to investigate at what age the PBDE concentrations peaked in an effort to focus exposure studies. This investigation involved the collection of blood samples from young age groups and the development of a simple model to predict PBDE concentrations by age in Australia.
Resumo:
Up to fifty per cent of individuals with Alcohol use disorders (AUD) also have alexithymia a personality construct hypothesized to be related to attachment difficulties. The relationship between alexithymia, craving, anxious attachment and alcohol-dependence severity was examined in 254 patients participating in a Cognitive-Behavioral Therapy (CBT) program for alcohol-dependence. Participants completed the Toronto Alexithymia Scale (TAS-20), the Obsessive Compulsive Drinking Scale (OCDS), the Revised Adult Attachment Anxiety Subscale (RAAS-Anxiety) and the Alcohol Use Disorder Identification Test (AUDIT). MANOVA indicated that individuals with alexithymia reported significantly higher levels of total OCDS, obsessive thoughts about alcohol, and compulsive drinking urges and behavior, compared to the non-alexithymic group. Regression analyses found that anxious attachment partially mediated the relationship between alexithymia and craving. Anxious attachment may be a potential treatment target to reduce alcohol consumption in those with alcohol-dependence and alexithymia. Research Highlights ► There were significant relationships of alexithymia, craving and anxious attachment. ► Alexithymic alcoholics reported higher levels of craving and alcoholism severity. ► Anxious attachment partially mediated the relationship of alexithymia and craving.
Resumo:
As AITPM National President, I was invited by Queensland’s Premier, Hon. Anna Bligh MP, as an audience guest to People’s Question Time on Wednesday 24 March 2010, which focused on ‘The Challenges and Opportunities of Population Growth in Queensland’. On the panel were: Premier and Minister for the Arts, Anna Bligh; Minister for Climate Change and Sustainability, Kate Jones; Minister for Infrastructure and Planning, Stirling Hinchliffe; Michael Rayner – Growth Management Summit Advisory Panel, Principal Director, Cox Rayner Architects; and Greg Hallam – Executive Director, Local Government Association of Queensland. The moderator for this session was Law Academic Erin O’Brien, of Queensland University of Technology.
Resumo:
Somatic embryogenesis and transformation systems are indispensable modern plant breeding components since they provide an alternative platform to develop control strategies against the plethora of pests and diseases affecting many agronomic crops. This review discusses some of the factors affecting somatic embryogenesis and transformation, highlights the advantages and limitations of these systems and explores these systems as breeding tools for the development of crops with improved agronomic traits. The regeneration of non-chimeric transgenic crops through somatic embryogenesis with introduced disease and pest-resistant genes for instance, would be of significant benefit to growers worldwide.
Resumo:
Genetic variation is the resource animal breeders exploit in stock improvement programs. Both the process of selection and husbandry practices employed in aquaculture will erode genetic variation levels overtime, hence the critical resource can be lost and this may compromise future genetic gains in breeding programs. The amount of genetic variation in five lines of Sydney Rock Oyster (SRO) that had been selected for QX (Queensland unknown) disease resistance were examined and compared with that in a wild reference population using seven specific SRO microsatellite loci. The five selected lines had significantly lower levels of genetic diversity than did the wild reference population with allelic diversity declining approximately 80%, but impacts on heterozygosity per locus were less severe. Significant deficiencies in heterozygotes were detected at six of the seven loci in both mass selected lines and the wild reference population. Against this trend however, a significant excess of heterozygotes was recorded at three loci Sgo9, Sgo14 and Sgo21 in three QX disease resistant lines (#2, #5 and #13). All populations were significantly genetic differentiated from each other based on pairwise FST values. A neighbour joining tree based on DA genetic distances showed a clear separation between all culture and wild populations. Results of this study show clearly, that the impacts of the stock improvement program for SRO has significantly eroded natural levels of genetic variation in the culture lines. This could compromise long-term genetic gains and affect sustainability of the SRO breeding program over the long-term.
Resumo:
Most salad vegetables are eaten fresh by consumers. However, raw vegetables may pose a risk of transmitting opportunistic bacteria to immunocompromised people, including cystic fibrosis (CF) patients. In particular, CF patients are vulnerable to chronic Pseudomonas aeruginosa lung infections and this organism is the primary cause of morbidity and mortality in this group. Clonal variants of P. aeruginosa have been identified as emerging threats to people afflicted with CF; however it has not yet been proven from where these clones originate or how they are transmitted. Due to the organisms‟ aquatic environmental niche, it was hypothesised that vegetables may be a source of these clones. To test this hypothesis, lettuce, tomatoes, mushrooms and bean sprout packages (n = 150) were analysed from a green grocer, supermarket and farmers‟ market within the Brisbane region, availability permitting. The internal and external surfaces of the vegetables were separately analysed for the presence of clonal strains of P. aeruginosa using washings and homogenisation techniques, respectively. This separation was in an attempt to establish which surface was contaminated, so that recommendations could be made to decrease or eliminate P. aeruginosa from these foods prior to consumption. Soil and water samples (n = 17) from local farms were also analysed for the presence of P. aeruginosa. Presumptive identification of isolates recovered from these environmental samples was made based on growth on Cetrimide agar at 42°C, presence of the cytochrome-oxidase enzyme and inability to ferment lactose. P. aeruginosa duplex real-time polymerase chain reaction assay (PAduplex) was performed on all bacterial isolates presumptively identified as P. aeruginosa. Enterobacterial repetitive intergenic consensus strain typing PCR (ERIC-PCR) was subsequently performed on confirmed bacterial isolates. Although 72 P. aeruginosa were isolated, none of these proved to be clonal strains. The significance of these findings is that vegetables may pose a risk of transmitting sporadic strains of P. aeruginosa to people afflicted with CF and possibly, other immunocompromised people.
Resumo:
1. A diverse array of patterns has been reported regarding the spatial extent of population genetic structure and effective dispersal in freshwater macroinvertebrates. In river systems, the movements of many taxa can be restricted to varying degrees by the natural stream channel hierarchy. 2. In this study, we sampled populations of the non-biting freshwater midge Echinocladius martini in the Paluma bioregion of tropical northeast Queensland to investigate fine scale patterns of within- and among-stream dispersal and gene flow within a purported historical refuge. We amplified a 639 bp fragment of mitochondrial COI and analysed genetic structure using pairwise ΦST, hierarchical AMOVA, Mantel tests and a parsimony network. Genetic variation was partitioned among stream sections using Streamtree to investigate the effect of potential instream dispersal barriers. 3. The data revealed strong natal site fidelity and significant differentiation among neighbouring, geographically proximate streams. We found evidence for only episodic adult flight among sites on separate stream reaches. Overall, however, our data suggested that both larval and adult dispersal was largely limited to within a stream channel. 4. This may arise from a combination of the high density of riparian vegetation physically restricting dispersal and from the joint effects of habitat stability and large population sizes. Together these may mitigate the requirement for movement among streams to avoid inbreeding and local extinction due to habitat change and may thus enable persistence of upstream populations in the absence of regular compensatory upstream flight. Taken together, these data suggest that dispersal of E. martini is highly restricted, to the scale of only a few kilometres, and hence occurs predominantly within the natal stream.
Resumo:
Objective Laser Doppler imaging (LDI) was compared to wound outcomes in children's burns, to determine if the technology could be used to predict these outcomes. Methods Forty-eight patients with a total of 85 burns were included in the study. Patient median age was 4 years 10 months and scans were taken 0–186 h post-burn using the fast, low-resolution setting on the Moor LDI2 laser Doppler imager. Wounds were managed by standard practice, without taking into account the scan results. Time until complete re-epithelialisation and whether or not grafting and scar management were required were recorded for each wound. If wounds were treated with Silvazine™ or Acticoat™ prior to the scan, this was also recorded. Results The predominant colour of the scan was found to be significantly related to the re-epithelialisation, grafting and scar management outcomes and could be used to predict those outcomes. The prior use of Acticoat™ did not affect the scan relationship to outcomes, however, the use of Silvazine™ did complicate the relationship for light blue and green scanned partial thickness wounds. Scans taken within the 24-h window after-burn also appeared to be accurate predictors of wound outcome. Conclusion Laser Doppler imaging is accurate and effective in a paediatric population with a low-resolution fast-scan.
Resumo:
Aim: This paper reports a study designed to assess the psychometric properties (validity and reliability) of a Turkish version of the Australian Parents’ Fever Management Scale (PFMS). Background: Little is known about childhood fever management among Turkish parents. No scales to measure parents’ fever management practices in Turkey are available. Design: This is a methodological study. Methods: Eighty parents, of febrile children aged six months to five years, were randomly selected from the paedaitric hospital and two community family health centers in Sakarya, Turkey. The PFMS was back translated; language equivalence and content validity were validated. PFMS and socio-demographic data were collected in 2009. Means and standard deviations were calculated for interval level data and p values greater than 0.05 were considered statistically significant. Unrotated principal component analysis was used to determine construct validity and Cronbach’s coefficient alpha determined the internal consistency reliability. Results: The PFMS was psychometrically sound in this population. Construct validity, confirmed by confirmatory factor analysis [KMO 0.812, Bartlett’s Specificity (χ² = 182.799, df=28, P < 0·001)] revealed the Turkish version to be comprised of the eight original PFMS items. Internal consistency reliability coefficient was 0.80 and the scale’s total-item correlation coefficients ranged from 0.15 to 0.66 and were significant (p<0.001). Interestingly parents reported high scores on the PFMS 34.52±4.60 (range 8-40 with 40 indicating a high burden of care for febrile children). Conclusion: The PFMS was as psychometrically robust in a Turkish population as in an Australian population and is, therefore, a useful tool for health professionals to identify parents’ practices, provide targeted education thereby in reducing the unnecessary burden of care they place on themselves when caring for a febrile child. Relevance to clinical practice. Testing in different populations, cultures and healthcare systems will further assist in reporting the PFMS usefulness in clinical practice and research.