Validity of currently used cutoff values of body mass index as a measure of obesity in Sri Lankan children

The aim of the study was to determine the reliability of body mass index based (BMI) cutoff values in diagnosing obesity among Sri Lankan children. Height, weight, waist circumference (WC) and hip circumference (HC) in 282 children were measured. Total body water was determined by deuterium dilution and fat mass (FM) derived using age and gender specific constants. A percentage FM of 30% for girls and 25% for boys were considered as cutoff levels for obesity. Two hundred and eighty two children (M/F: 158/124) were studied and 99 (80%) girls and 72 (45.5%) boys were obese based on % body fat. Eight (6.4%) girls and nine (5.7%) boys were obese based on International Obesity Task Force (IOTF) cutoff values. Percentage FM and WC centile charts were able to diagnose a significant proportion of children as true obese children. The FM and BMI were closely associated in both girls (r = 0.82, p < 0.001) and boys (r = 0.87, p < 0.001). Percentage FM and BMI had a very low but significant association; girls (r = 0.32, p < 0.001) and boys (r = 0.68, p < 0.001). FM had a significant association with WC and HC. BMI based cutoff values had a specificity of 100% but a very low sensitivity, varying between 8% and 23.6%. BMI is a poor indicator of the percentage fat and the commonly used cutoff values were not sensitive to detect cases of childhood obesity in Sri Lankan children.

Site and gender specificity of inheritance of bone mineral density

Differences in genetic control of BMD by skeletal sites and genders were examined by complex segregation analysis in 816 members of 147 families with probands with extreme low BMD. Spine BMD correlated more strongly in male-male comparisons and hip BMD in female-female comparisons, consistent with gender- and site-specificity of BMD heritability. Introduction: Evidence from studies in animals and humans suggests that the genetic control of bone mineral density (BMD) may differ at different skeletal sites and between genders. This question has important implications for the design and interpretation of genetic studies of osteoporosis. Methods: We examined the genetic profile of 147 families with 816 individuals recruited through probands with extreme low BMD (T-score < −2.5, Z-score < −2.0). Complex segregation analysis was performed using the Pedigree Analysis Package. BMD was measured by DXA at both lumbar spine (L1-L4) and femoral neck. Results: Complex segregation analysis excluded purely monogenic and environmental models of segregation of lumbar spine and femoral neck BMD in these families. Pure polygenic models were excluded at the lumbar spine when menopausal status was considered as a covariate, but not at the femoral neck. Mendelian models with a residual polygenic component were not excluded. These models were consistent with the presence of a rare Mendelian genotype of prevalence 3–19 %, causing high BMD at the hip and spine in these families, with additional polygenic effects. Total heritability range at the lumbar spine was 61–67 % and at the femoral neck was 44–67 %. Significant differences in correlation of femoral neck and lumbar spine BMD were observed between male and female relative pairs, with male-male comparisons exhibiting stronger lumbar spine BMD correlation than femoral neck, and female-female comparisons having greater femoral neck BMD correlation than lumbar spine. These findings remained true for parent-offspring correlations when menopausal status was taken into account. The recurrence risk ratio for siblings of probands of a Z-score < −2.0 was 5.4 at the lumbar spine and 5.9 at the femoral neck. Conclusions: These findings support gender- and site-specificity of the inheritance of BMD. These results should be considered in the design and interpretation of genetic studies of osteoporosis.

Functional activation during the Rapid Visual Information Processing task in a middle aged cohort: An fMRI study

The Rapid Visual Information Processing (RVIP) task, a serial discrimination task where task performance believed to reflect sustained attention capabilities, is widely used in behavioural research and increasingly in neuroimaging studies. To date, functional neuroimaging research into the RVIP has been undertaken using block analyses, reflecting the sustained processing involved in the task, but not necessarily the transient processes associated with individual trial performance. Furthermore, this research has been limited to young cohorts. This study assessed the behavioural and functional magnetic resonance imaging (fMRI) outcomes of the RVIP task using both block and event-related analyses in a healthy middle aged cohort (mean age = 53.56 years, n = 16). The results show that the version of the RVIP used here is sensitive to changes in attentional demand processes with participants achieving a 43% accuracy hit rate in the experimental task compared with 96% accuracy in the control task. As shown by previous research, the block analysis revealed an increase in activation in a network of frontal, parietal, occipital and cerebellar regions. The event related analysis showed a similar network of activation, seemingly omitting regions involved in the processing of the task (as shown in the block analysis), such as occipital areas and the thalamus, providing an indication of a network of regions involved in correct trial performance. Frontal (superior and inferior frontal gryi), parietal (precuenus, inferior parietal lobe) and cerebellar regions were shown to be active in both the block and event-related analyses, suggesting their importance in sustained attention/vigilance. These networks and the differences between them are discussed in detail, as well as implications for future research in middle aged cohorts.

Expert Identity in Development of Core-Task-Oriented Working Practices for Mastering Demanding Situations

The point of departure in this dissertation was the practical safety problem of unanticipated, unfamiliar events and unexpected changes in the environment, the demanding situations which the operators should take care of in the complex socio-technical systems. The aim of this thesis was to increase the understanding of demanding situations and of the resources for coping with these situations by presenting a new construct, a conceptual model called Expert Identity (ExId) as a way to open up new solutions to the problem of demanding situations and by testing the model in empirical studies on operator work. The premises of the Core-Task Analysis (CTA) framework were adopted as a starting point: core-task oriented working practices promote the system efficiency (incl. safety, productivity and well-being targets) and that should be supported. The negative effects of stress were summarised and the possible countermeasures related to the operators' personal resources such as experience, expertise, sense of control, conceptions of work and self etc. were considered. ExId was proposed as a way to bring emotional-energetic depth into the work analysis and to supplement CTA-based practical methods to discover development challenges and to contribute to the development of complex socio-technical systems. The potential of ExId to promote understanding of operator work was demonstrated in the context of the six empirical studies on operator work. Each of these studies had its own practical objectives within the corresponding quite broad focuses of the studies. The concluding research questions were: 1) Are the assumptions made in ExId on the basis of the different theories and previous studies supported by the empirical findings? 2) Does the ExId construct promote understanding of the operator work in empirical studies? 3) What are the strengths and weaknesses of the ExId construct? The layers and the assumptions of the development of expert identity appeared to gain evidence. The new conceptual model worked as a part of an analysis of different kinds of data, as a part of different methods used for different purposes, in different work contexts. The results showed that the operators had problems in taking care of the core task resulting from the discrepancy between the demands and resources (either personal or external). The changes of work, the difficulties in reaching the real content of work in the organisation and the limits of the practical means of support had complicated the problem and limited the possibilities of the development actions within the case organisations. Personal resources seemed to be sensitive to the changes, adaptation is taking place, but not deeply or quickly enough. Furthermore, the results showed several characteristics of the studied contexts that complicated the operators' possibilities to grow into or with the demands and to develop practices, expertise and expert identity matching the core task. They were: discontinuation of the work demands, discrepancy between conceptions of work held in the other parts of organisation, visions and the reality faced by the operators, emphasis on the individual efforts and situational solutions. The potential of ExId to open up new paths to solving the problem of the demanding situations and its ability to enable studies on practices in the field was considered in the discussion. The results were interpreted as promising enough to encourage the conduction of further studies on ExId. This dissertation proposes especially contribution to supporting the workers in recognising the changing demands and their possibilities for growing with them when aiming to support human performance in complex socio-technical systems, both in designing the systems and solving the existing problems.

Host-specificity of Salmonella enterica serovar Gallinarum: Insights from comparative genomics

In this study, we have identified the possible genetic factors responsible for fowl-adaptation of Salmonella enterica serovar Gallinarum (S. Gallinarum). By comparing the genes related to Salmonella pathogenicity islands (SPI) of S. Gallinarum with those of Salmonella enterica serovar Enteritidis (S. Enteritidis) we have identified twenty-four positively selected genes. Our results suggest that the genes encoding the structural components of SPI-2 encoded type three secretion apparatus (TTSS) and the effector proteins that are secreted via SPI-1 encoded TTSS have evolved under positive selection pressure in these serovars. We propose that these positively selected genes play important roles in conferring different host-specificities to S. Gallinarum and S. Enteritidis.

Specificity of Carvalhotingis visenda (Hemiptera: Tingidae) as a biological control agent for cat's claw creeper Macfadyena unguis-cati (Bignoniaceae) in Australia

Biological control is considered the most suitable management option for cat's claw creeper, Macfadyena unguis-cati, a major environmental weed in coastal and sub-coastal areas of Queensland and New South Wales, Australia. The potential host range of the leaf-sucking bug, Carvalhotingis visenda (Hemiptera: Tingidae) was evaluated on the basis of nymphal survival and development, adult feeding and survival, and oviposition preference using choice and no-choice tests involving 38 plant species in 10 families. In no-choice tests, although adults survived on a few of the non-target plants, no eggs were laid on any of the non-target plants. In no-choice condition, the tingid oviposits and completes nymphal development only on M. unguis-cati. There was also no visible feeding damage on any of the non-target plants. In choice tests, adults showed distinct preference for M. unguis-cati, and the preference level increased over time as the tingids moved away from the non-target plants. At the end of the trial no adults were evident on any of the non-target plants. Host specificity tests confirm that the tingid is a highly host specific biocontrol agent, and does not pose risk to any non-target plants in Australia. This agent has been approved for field release by the relevant regulatory authorities in Australia.

Towards Ecologically Sustainable Management of the Torres Strait Prawn Fishery. CRC Torres Strait Task T1.5 – Final Report

This publication, which is the final report to the Torres Strait Cooperative Research Centre, provides an overview of all the research that was conducted as part of the Torres Strait CRC Task 1.5 - Towards Ecologically Sustainable Management of the Torres Strait Prawn Fishery The objectives of the task were: To develop cost-effective protocols to monitor and quantify the bycatch and environmental impacts of commercial prawn trawling. To monitor the status of target species using both fishery dependent and fishery independent data. To develop biological reference points for target species and undertake management strategy evaluation, in particular a risk assessment of fishing at various levels of fishing mortality. This report focuses on the second component of objective 1 and details a comparative analysis of bycatch samples collected from areas of the Torres Strait that were both closed and open to prawn trawl fishing. The report also reviews the research conducted in relation to objectives 2 and 3 which are detailed in a separate report, Stock Assessment of the Torres Strait Tiger Prawn Fishery (Penaeus esculentus).

Austropleospora osteospermi gen. et sp nov and its host specificity and distribution on Chrysanthemoides monilifera ssp rotundata in Australia.

Hendersonia osteospermi was found for the first time in Australia on leaf spots of the introduced invasive plant Chrysanthemoides monilifera ssp. rotundata (bitou bush) in coastal regions of New South Wales. Pathogenicity tests on species from 11 tribes in the family Asteraceae, demonstrated that H. osteospermi caused severe necrosis on leaves and stems of C. monilifera ssp. rotundata and its congener C. monilifera ssp. monilifera (boneseed). Small necrotic spots also developed on Osteospermum fruticosum and Dimorphotheca cuneata in the Calenduleae and on Helianthus annuus (sunflower) in the Heliantheae. None of the other plant species tested developed leaf spots, although H. osteospermi was re-isolated from senescent leaves of Cynara scolymus (globe artichoke) in the Cynareae and Vernonia cinerea in the Vernonieae. Single ascospores from ascomata of a Pleospora-like fungus found on diseased stems of bitou bush produced H. osteospermi in culture, which proved the anamorph/teleomorph connection. The ITS region of both a single-ascospore isolate and a single-conidium isolate were sequenced and found to be identical. The taxonomic status of H. osteospermi is re-examined and Austropleospora osteospermi gen. et sp. nov. is described as its teleomorph based on morphology, host range tests and DNA sequence analysis. The potential of A. osteospermi for the biological control of bitou bush and boneseed in Australia is discussed.

Estrogen Induction Of Biotin-Binding Protein In Immature Chicks - Kinetics, Hormonal Specificity And Modulation

Employing a specific radioimmunoassay for quantification, the kinetics of estrogen-induced elevation in the plasma concentration of biotin-binding protein (BBP) in immature male chicks was investigated. A single injection of the steroid hormone enhanced the plasma BBP content several-fold at 6 h, reaching peak levels around 48 h and declining thereafter. A 2-fold amplification of the response was evident during secondary stimulation with the hormone. The magnitude of the response was hormonal dose-dependent while the initial lag phase and the time of peak protein accumulation were unaltered within the hormonal doses tested. The circulatory half-life of the specific protein in normal and estrogenized birds was 10 h. Hyperthyroidism markedly decreased the hormonal response while the opposite effect was seen during hypothyroidism. The antiestrogens E- and Z-clomiphene citrate effectively blocked the protein induction whereas progesterone, either alone or in combination with estrogen, was ineffective in modulating the induction. Cycloheximide administration drastically inhibited the inductive response. The above observations clearly suggest that the genes corresponding to the two isofunctional proteins of chicken egg, viz. BBP and avidin, are differentially regulated.

Specificity of deoxycytidylate antibodies

Antibodies to deoxycytidylate (dpC) were elicited in rabbits using a thyroglobulin (Tg) conjugate of dpC. The specificity of the antibodies was determined by measuring the inhibition of the binding of [3H]dpC to the antibodies by various non-radioactive nucleotides or derivatives. The antibodies were found to distinguish dpC from pC and DNA from RNA, probably due to their specificity for the conformation of the deoxycytidylate.

Specificity of protein - Nucleic acid interaction and the biochemical evolution

The water soluble carbodiimide mediated condensation of dipeptides of the general form Gly-X was carried out in the presence of mono- and poly-nucleotides. The observed yield of the tetrapeptide was found to be higher for peptide-nucleotide system of higher interaction specificity following mainly the anticodon-amino acid relationship (Basu, H.S. & Podder, S.K., 1981, Ind. J. Biochem. Biophys.,19, 251-253). The yield of the condensation product of L-peptide was more because of its higher interaction specificity. The extent of the racemization during the condensation of Gly-L-Phe, Gly-L-Tyr and Gly-D-Phe was found to be dependent on the specificity of the interaction -the higher the specificity, the lesser the racemization. The product formed was shown to have a catalytic effect on the condensation reaction. These data thus provide a mechanism showing how the specific interaction between amino acids/dipeptides and nucleic acids could lead to the formation of the lsquoprimitiversquo translation machinery.

Induction of riboflavin-carrier protein in the immature male rat by estrogen: kinetic and hormonal specificity

The kinetics of estrogen-induced accumulation of riboflavin-carrier protein in the plasma was investigated in immature male rats using a specific and sensitive homologous radio-immunoassay procedure developed for this purpose. Following a single injection of the steroid hormone, plasma riboflavin-carrier protein levels increased markedly after an initial lag period of approximately 24 h, reaching peak levels around 96 h and declining thereafter. A 1.5 fold amplification of the inductive response was evident on secondary stimulation with the hormone. The magnitude of the response was dependent on hormonal dose, whereas the initial lag phase and the time of peak riboflavin-carrier protein induction were unaltered within the range of the steroid doses (0.1–10 mg/ kg body wt.) tested. Simultaneous administration of progesterone did not affect either the kinetics or the maximum level of the protein induced. The hormonal specificity of this induction was further adduced by the effect of administration of antiestrogens viz., En and Zu chlomiphene citrates, which effectively curtailed hormonal induction of the protein. That the induction involvedde novo-protein synthesis was evident from the complete inhibition obtained upon administration of cycloheximide. Passive immunoneutralization of endogenous riboflavin-carrier protein with antiserum to the homologous protein terminated pregnancy in rats confirming the earlier results with antiserum to chicken riboflavin-carrier protein.

Immunologic studies on nucleic acids and their components. I. An analysis of the specificity of anti-deoxyadenylate antibodies by a membrane-binding technique

Anti-deoxyadenylate antibodies were produced in rabbits by injecting a conjugate of deoxyadenosine 5′-phosphate with bovine serum albumin. The antisera, as analyzed by double diffusion in agar and the quantitative precipitin reaction, showed hapten-specific antibodies. The specific interaction between [3H]deoxyadenylate and antiserum was studied by a sensitive nitrocellulose membrane-binding assay. The specificity of the antibodies was analyzed by measuring the effectiveness of other nucleotides or derivatives to inhibit the hapten-antibody binding. The requirements for recognition by the antibody sites were studied by using a series of naturally occurring nucleic acid components as well as some synthetic derivatives as inhibitors. The antibodies were found to show a high degree of specificity for the whole nucleotide, the base, sugar and phosphate playing almost equally important roles. There was cross reactivity with other mononucleotides, although of a low order. The antibodies were able to react with DNA and tRNA.

Overparenting and homework: The student’s task, but everyone’s responsibility

A high level of parental involvement is widely considered to be essential for optimal child and adolescent development and wellbeing, including academic success. However, recent consideration has been given to the idea that extremely high levels of parental involvement (often called ‘overparenting’ or ‘helicopter parenting’) might not be beneficial. This study used a newly created overparenting measure, the Locke Parenting Scale (LPS), to investigate the association of overparenting and children’s homework. Eight hundred and sixty-six parents completed online questionnaires about their parenting beliefs and intentions, and their attitudes associated with their child’s homework. Parents with higher LPS scores tended to take more personal responsibility for the completion of their child’s homework than did other parents, and ascribed greater responsibility for homework completion to their child’s teacher. However, increased perceived responsibility by parents and teachers was not accompanied by a commensurate reduction in what they perceived was the child’s responsibility. Future research should examine whether extreme parental attitudes and reported behaviours translate to validated changes in actual homework support.

Development and testing of allometric equations for estimating above-ground biomass of mixed-species environmental plantings

To quantify the impact that planting indigenous trees and shrubs in mixed communities (environmental plantings) have on net sequestration of carbon and other environmental or commercial benefits, precise and non-biased estimates of biomass are required. Because these plantings consist of several species, estimation of their biomass through allometric relationships is a challenging task. We explored methods to accurately estimate biomass through harvesting 3139 trees and shrubs from 22 plantings, and collating similar datasets from earlier studies, in non-arid (>300mm rainfallyear-1) regions of southern and eastern Australia. Site-and-species specific allometric equations were developed, as were three types of generalised, multi-site, allometric equations based on categories of species and growth-habits: (i) species-specific, (ii) genus and growth-habit, and (iii) universal growth-habit irrespective of genus. Biomass was measured at plot level at eight contrasting sites to test the accuracy of prediction of tonnes dry matter of above-ground biomass per hectare using different classes of allometric equations. A finer-scale analysis tested performance of these at an individual-tree level across a wider range of sites. Although the percentage error in prediction could be high at a given site (up to 45%), it was relatively low (<11%) when generalised allometry-predictions of biomass was used to make regional- or estate-level estimates across a range of sites. Precision, and thus accuracy, increased slightly with the level of specificity of allometry. Inclusion of site-specific factors in generic equations increased efficiency of prediction of above-ground biomass by as much as 8%. Site-and-species-specific equations are the most accurate for site-based predictions. Generic allometric equations developed here, particularly the generic species-specific equations, can be confidently applied to provide regional- or estate-level estimates of above-ground biomass and carbon. © 2013 Elsevier B.V.