987 resultados para Cooper pairing


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Ankylosing spondylitis (AS) has been associated with human leukocyte antigen (HLA)-B27 for over 30 years; however, the mechanism of action has remained elusive. Although many studies have reported associations between AS and other genes in the major histocompatibility complex (MHC) in AS, no conclusive results have emerged. To investigate the contribution of non-B27 MHC genes to AS, a large cohort of AS families and controls were B27 typed and genotyped across the region. Interrogation of the data identified a region of 270kb, lying from 31952649 to 32221738 base pairs from the p-telomere of chromosome 6 and containing 23 genes, which is likely to include genes involved with susceptibility to AS.

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The major histocompatibility complex (MHC) on chromosome 6 is associated with susceptibility to more common diseases than any other region of the human genome, including almost all disorders classified as autoimmune. In type 1 diabetes the major genetic susceptibility determinants have been mapped to the MHC class II genes HLA-DQB1 and HLA-DRB1 (refs 1–3), but these genes cannot completely explain the association between type 1 diabetes and the MHC region4, 5, 6, 7, 8, 9, 10, 11. Owing to the region's extreme gene density, the multiplicity of disease-associated alleles, strong associations between alleles, limited genotyping capability, and inadequate statistical approaches and sample sizes, which, and how many, loci within the MHC determine susceptibility remains unclear. Here, in several large type 1 diabetes data sets, we analyse a combined total of 1,729 polymorphisms, and apply statistical methods—recursive partitioning and regression...

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Background The Global Burden of Disease Study 2013 (GBD 2013) aims to bring together all available epidemiological data using a coherent measurement framework, standardised estimation methods, and transparent data sources to enable comparisons of health loss over time and across causes, age–sex groups, and countries. The GBD can be used to generate summary measures such as disability-adjusted life-years (DALYs) and healthy life expectancy (HALE) that make possible comparative assessments of broad epidemiological patterns across countries and time. These summary measures can also be used to quantify the component of variation in epidemiology that is related to sociodemographic development. Methods We used the published GBD 2013 data for age-specific mortality, years of life lost due to premature mortality (YLLs), and years lived with disability (YLDs) to calculate DALYs and HALE for 1990, 1995, 2000, 2005, 2010, and 2013 for 188 countries. We calculated HALE using the Sullivan method; 95% uncertainty intervals (UIs) represent uncertainty in age-specific death rates and YLDs per person for each country, age, sex, and year. We estimated DALYs for 306 causes for each country as the sum of YLLs and YLDs; 95% UIs represent uncertainty in YLL and YLD rates. We quantified patterns of the epidemiological transition with a composite indicator of sociodemographic status, which we constructed from income per person, average years of schooling after age 15 years, and the total fertility rate and mean age of the population. We applied hierarchical regression to DALY rates by cause across countries to decompose variance related to the sociodemographic status variable, country, and time. Findings Worldwide, from 1990 to 2013, life expectancy at birth rose by 6·2 years (95% UI 5·6–6·6), from 65·3 years (65·0–65·6) in 1990 to 71·5 years (71·0–71·9) in 2013, HALE at birth rose by 5·4 years (4·9–5·8), from 56·9 years (54·5–59·1) to 62·3 years (59·7–64·8), total DALYs fell by 3·6% (0·3–7·4), and age-standardised DALY rates per 100 000 people fell by 26·7% (24·6–29·1). For communicable, maternal, neonatal, and nutritional disorders, global DALY numbers, crude rates, and age-standardised rates have all declined between 1990 and 2013, whereas for non–communicable diseases, global DALYs have been increasing, DALY rates have remained nearly constant, and age-standardised DALY rates declined during the same period. From 2005 to 2013, the number of DALYs increased for most specific non-communicable diseases, including cardiovascular diseases and neoplasms, in addition to dengue, food-borne trematodes, and leishmaniasis; DALYs decreased for nearly all other causes. By 2013, the five leading causes of DALYs were ischaemic heart disease, lower respiratory infections, cerebrovascular disease, low back and neck pain, and road injuries. Sociodemographic status explained more than 50% of the variance between countries and over time for diarrhoea, lower respiratory infections, and other common infectious diseases; maternal disorders; neonatal disorders; nutritional deficiencies; other communicable, maternal, neonatal, and nutritional diseases; musculoskeletal disorders; and other non-communicable diseases. However, sociodemographic status explained less than 10% of the variance in DALY rates for cardiovascular diseases; chronic respiratory diseases; cirrhosis; diabetes, urogenital, blood, and endocrine diseases; unintentional injuries; and self-harm and interpersonal violence. Predictably, increased sociodemographic status was associated with a shift in burden from YLLs to YLDs, driven by declines in YLLs and increases in YLDs from musculoskeletal disorders, neurological disorders, and mental and substance use disorders. In most country-specific estimates, the increase in life expectancy was greater than that in HALE. Leading causes of DALYs are highly variable across countries. Interpretation Global health is improving. Population growth and ageing have driven up numbers of DALYs, but crude rates have remained relatively constant, showing that progress in health does not mean fewer demands on health systems. The notion of an epidemiological transition—in which increasing sociodemographic status brings structured change in disease burden—is useful, but there is tremendous variation in burden of disease that is not associated with sociodemographic status. This further underscores the need for country-specific assessments of DALYs and HALE to appropriately inform health policy decisions and attendant actions.

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Background The Global Burden of Disease, Injuries, and Risk Factor study 2013 (GBD 2013) is the first of a series of annual updates of the GBD. Risk factor quantification, particularly of modifiable risk factors, can help to identify emerging threats to population health and opportunities for prevention. The GBD 2013 provides a timely opportunity to update the comparative risk assessment with new data for exposure, relative risks, and evidence on the appropriate counterfactual risk distribution. Methods Attributable deaths, years of life lost, years lived with disability, and disability-adjusted life-years (DALYs) have been estimated for 79 risks or clusters of risks using the GBD 2010 methods. Risk–outcome pairs meeting explicit evidence criteria were assessed for 188 countries for the period 1990–2013 by age and sex using three inputs: risk exposure, relative risks, and the theoretical minimum risk exposure level (TMREL). Risks are organised into a hierarchy with blocks of behavioural, environmental and occupational, and metabolic risks at the first level of the hierarchy. The next level in the hierarchy includes nine clusters of related risks and two individual risks, with more detail provided at levels 3 and 4 of the hierarchy. Compared with GBD 2010, six new risk factors have been added: handwashing practices, occupational exposure to trichloroethylene, childhood wasting, childhood stunting, unsafe sex, and low glomerular filtration rate. For most risks, data for exposure were synthesised with a Bayesian meta-regression method, DisMod-MR 2.0, or spatial-temporal Gaussian process regression. Relative risks were based on meta-regressions of published cohort and intervention studies. Attributable burden for clusters of risks and all risks combined took into account evidence on the mediation of some risks such as high body-mass index (BMI) through other risks such as high systolic blood pressure and high cholesterol. Findings All risks combined account for 57·2% (95% uncertainty interval [UI] 55·8–58·5) of deaths and 41·6% (40·1–43·0) of DALYs. Risks quantified account for 87·9% (86·5–89·3) of cardiovascular disease DALYs, ranging to a low of 0% for neonatal disorders and neglected tropical diseases and malaria. In terms of global DALYs in 2013, six risks or clusters of risks each caused more than 5% of DALYs: dietary risks accounting for 11·3 million deaths and 241·4 million DALYs, high systolic blood pressure for 10·4 million deaths and 208·1 million DALYs, child and maternal malnutrition for 1·7 million deaths and 176·9 million DALYs, tobacco smoke for 6·1 million deaths and 143·5 million DALYs, air pollution for 5·5 million deaths and 141·5 million DALYs, and high BMI for 4·4 million deaths and 134·0 million DALYs. Risk factor patterns vary across regions and countries and with time. In sub-Saharan Africa, the leading risk factors are child and maternal malnutrition, unsafe sex, and unsafe water, sanitation, and handwashing. In women, in nearly all countries in the Americas, north Africa, and the Middle East, and in many other high-income countries, high BMI is the leading risk factor, with high systolic blood pressure as the leading risk in most of Central and Eastern Europe and south and east Asia. For men, high systolic blood pressure or tobacco use are the leading risks in nearly all high-income countries, in north Africa and the Middle East, Europe, and Asia. For men and women, unsafe sex is the leading risk in a corridor from Kenya to South Africa. Interpretation Behavioural, environmental and occupational, and metabolic risks can explain half of global mortality and more than one-third of global DALYs providing many opportunities for prevention. Of the larger risks, the attributable burden of high BMI has increased in the past 23 years. In view of the prominence of behavioural risk factors, behavioural and social science research on interventions for these risks should be strengthened. Many prevention and primary care policy options are available now to act on key risks.

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Genetic studies based on cohorts with rare and extreme bone phenotypes have shown that the LRP5 gene is an important genetic modulator of BMD. Using family-based and case-control approaches, this study examines the role of the LRP5 gene in determining normal population variation of BMD and describes significant association and suggestive linkage between LRP5 gene polymorphisms and BMD in >900 individuals with a broad range of BMD. Introduction: Osteoporosis is a common, highly heritable condition determined by complex interactions of genetic and environmental etiologies. Genetic factors alone can account for 50-80% of the interindividual variation in BMD. Mutations in the LRP5 gene on chromosome 11q12-13 have been associated with rare syndromes characterized by extremely low or high BMD, but little is known about the contribution of this gene to the development of osteoporosis and determination of BMD in a normal population. Materials and Methods: To examine the entire spectrum of low to high BMD, 152 osteoporotic probands, their families (597 individuals), and 160 women with elevated BMD (T score > 2.5) were recruited. BMD at the lumbar spine, femoral neck, and hip were measured in each subject using DXA. Results: PAGE sequencing of the LRP5 gene revealed 10 single nucleotide polymorphisms (SNPs), 8 of which had allele frequencies of >5%, in exons 8, 9, 10, 15, and 18 and in introns 6, 7, and 21. Within families, a strong association was observed between an SNP at nucleotide C171346A in intron 21 and total hip BMD (p < 1 × 10-5 in men only, p = 0.0019 in both men and women). This association was also observed in comparisons of osteoporotic probands and unrelated elevated BMD in women (p = 0.03), along with associations with markers in exons 8 (C135242T, p = 0.007) and 9 (C141759T, p = 0.02). Haplotypes composed of two to three of the SNPs G121513A, C135242T, G138351A, and C141759T were strongly associated with BMD when comparing osteoporotic probands and high BMD cases (p < 0.003). An SNP at nucleotide C165215T in exon 18 was linked to BMD at the lumbar spine, femoral neck, and total hip (parametric LOD scores = 2.8, 2.5, and 2.2 and nonparametric LOD scores = 0.3, 1.1, and 2.2, respectively) but was not genetically associated with BMD variation. Conclusion: These results show that common LRP5 polymorphisms contribute to the determination of BMD in the general population.

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A continuum for describing the degree to which teachers interpret the various features of a curriculum is presented. The continuum has been developed based upon the observation of classroom practices and discussions with a group of teachers who are using an innovative junior secondary mathematics curriculum. It is anticipated that the ongoing use of the continuum will lead to its improvement as well as the refinement of the curriculum, more focussed support for the teachers,improved student learning, and the building of explanatory theory regarding mathematics teaching and learning.

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In this paper we explore some of the ethical issues associated with conducting Ethnographic Action Research (Tacchi, 2004; Tacchi et al., 2003) for understanding and facilitating distributed collaboration. Ethnography and action research are increasingly popular qualitative approaches to researching computer-supported collaboration and we are applying them together in a project within a distributed research centre. We identify ethical principles applied to the conduct of research in Australia and we briefly describe a number of ethical problems that arise due to the nature of Ethnographic Action Research.

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Mr=300.33 , triclinic, P1, a=5.635 (2), b=11.077(2), c=11.582(2)A, a= 70.48 (1), fl= 88.16 (3), y=80.56(3) ° , V= 670.325 A3, Z=2, D x = 1.49 Mg m -3, Cu Ka, n= 1.54184 ,A, g = 2.308mm -1, F(000)=316, T=301K, R=0.054, R w = 0.093 for 1944 observed counter reflections. The sulphur position with respect to the dihydrouracil ring, which is of possible relevance to the action of thymidylate synthetase, is axial in molecule A and equatorial in B. Both molecules show the anti conformation about the glycosidic bond [torsion angle C(6)-N(1)-C(1')-O(4'), 2'CN = 21.6 (9) and 29.4 (10) °] and have the C(4')-endo, O(4')-exo (40T) sugar conformation. The dioxolane-ring conformation is O(2')-endo in A and C(7)-endo in B. The dihydrouracil rings show self base pairing with hydrogen bondsN(3A)...O(ZB) and N(3B)...O(ZA).

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The Watson-Crick type of base pairing is considered to be mandatory for the formation of duplex DNA. However, conformational calculations carried out in our laboratory, have shown that some combinations of backbone torsion angles and sugar pucker lead to duplexes with Hoogsteen type of base pairing also. Here we present the results of energy calculations performed on A-T containing doublet sequences in the D-form with both Hoogsteen and Watson-Crick type of base pairing and the 3 viable models for the A-T containing polynucleotide duplex poly[d(A-T)].

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Field surveys of egg parasitoids of the diamondback moth, Plutella xylostella, were conducted at Redlands and Gatton, south-east Queensland. Eggs of P. xylostella were present all year round in both localities, and parasitized eggs were consistently found between late spring and early winter. Percent parasitism in the range 30–75% was recorded on many occasions, although rates less than 10% were more common. The major parasitoids included Trichogrammatoidea bactrae Nagaraja and Trichogramma pretiosum Riley. Laboratory evaluation showed that the T. pretiosum from Gatton has a high capacity to parasitize P. xylostella eggs under suitable conditions. This study represents the first record of egg parasitoids of P. xylostella from Australia.

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Field trials and laboratory bioassays were undertaken to compare the performance and efficacy (mortality of diamondback moth larvae) of insecticides applied to cabbages with three high volume hydraulic knapsack sprayers (NS-16, PB-20 and Selecta 12V) and a controlled droplet application (CDA) sprayer. In field experiments, the high volume knapsack sprayers (application rate 500-600 L ha-') provided better spray coverage on the upper and lower surfaces of inner leaves, the upper surfaces of middle and outer leaves, and greater biological efficacy than the CDA sprayer (application rate 20~40 L ha-'). The PB-20 provided better spray coverage on the upper surface of middle leaves and both Surfaces of outer leaves when compared with the Selecta I2V. However, its biological efficacy in the field was not significantly different from that of the other high volume sprayers. Increasing the application rate from 20 to 40 L ha - ' for the CDA sprayer significantly increased droplet density but had no impact on test insect mortality. Laboratory evaluations of biological efficacy yielded higher estimates than field evaluations and there was no significant difference between the performance of the PB-20 and the CDA sprayer. Significant positive relationships were detected between insect mortality and droplet density deposited for both the PB-20 and the CDA sprayers

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In newly invaded communities, interspecific competition is thought to play an important role in determining the success of the invader and its impact on the native community. In southern Australia, the native Polistes humilis was the predominant social wasp prior to the arrival of the exotic Vespula germanica (Hymenoptera: Vespidae). Both species forage for similar resources (water, pulp, carbohydrate and protein prey), and concerns have arisen about potential competition between them. The aim of this study was to identify the protein foods that these wasps feed on. As many prey items are masticated by these wasps to the degree that they cannot be identified using conventional means, morphological identification was complemented by sequencing fragments of the mitochondrial 16S rRNA gene. GenBank searches using blast and phylogenetic analyses were used to identify prey items to at least order level. The results were used to construct complete prey inventories for the two species. These indicate that while P. humilis is restricted to feeding on lepidopteran larvae, V. germanica collects a variety of prey of invertebrate and vertebrate origin. Calculated values of prey overlap between the two species are used to discuss the implications of V. germanica impacting on P. humilis. Results obtained are compared to those gained by solely 'conventional' methods, and the advantages of using DNA-based taxonomy in ecological studies are emphasized.

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Continuous cultivation and cereal cropping of southern Queensland soils previously supporting native vegetation have resulted in reduced soil nitrogen supply, and consequently decreased cereal grain yields and low grain protein. To enhance yields and protein concentrations of wheat, management practices involving N fertiliser application, with no-tillage and stubble retention, grain legumes, and legume leys were evaluated from 1987 to 1998 on a fertility-depleted Vertosol at Warra, southern Queensland. The objective of this study was to examine the effect of lucerne in a 2-year lucerne–wheat rotation for its nitrogen and disease-break benefits to subsequent grain yield and protein content of wheat as compared with continuous wheat cropping. Dry matter production and nitrogen yields of lucerne were closely correlated with the total rainfall for October–September as well as March–September rainfall. Each 100 mm of total rainfall resulted in 0.97 t/ha of dry matter and 26 kg/ha of nitrogen yield. For the March–September rainfall, the corresponding values were 1.26 t/ha of dry matter and 36 kg/ha of nitrogen yield. The latter values were 10% lower than those produced by annual medics during a similar period. Compared with wheat–wheat cropping, significant increases in total soil nitrogen were observed only in 1990, 1992 and 1994 but increases in soil mineralisable nitrogen were observed in most years following lucerne. Similarly, pre-plant nitrate nitrogen in the soil profile following lucerne was higher by 74 kg/ha (9–167 kg N/ha) than that of wheat–wheat without N fertiliser in all years except 1996. Consequently, higher wheat grain protein (7 out of 9 seasons) and grain yield (4 out of 9 seasons) were produced compared with continuous wheat. There was significant depression in grain yield in 2 (1993 and 1995) out of 9 seasons attributed to soil moisture depletion and/or low growing season rainfall. Consequently, the overall responses in yield were lower than those of 50 kg/ha of fertiliser nitrogen applied to wheat–wheat crops, 2-year medic–wheat or chickpea–wheat rotation, although grain protein concentrations were higher following lucerne. The incidence and severity of the soilborne disease, common root rot of wheat caused by Bipolaris sorokiniana, was generally higher in lucerne–wheat than in continuous wheat with no nitrogen fertiliser applications, since its severity was significantly correlated with plant available water at sowing. No significant incidence of crown rot or root lesion nematode was observed. Thus, productivity, which was mainly due to nitrogen accretion in this experiment, can be maintained where short duration lucerne leys are grown in rotations with wheat.

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Fashion and war don’t seem an obvious pairing, but the military jacket is a fashion staple. It may take the form of a double-breasted dress uniform with brass buttons and epaulettes, trimmed in rock star braid, or it may be a khaki combat jacket, worn with Doc Martens and a scowl. Here I explore how these two forms of the military jacket were frogmarched into fashion...

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Soil nitrogen (N) supply in the Vertosols of southern Queensland, Australia has steadily declined as a result of long-term cereal cropping without N fertiliser application or rotations with legumes. Nitrogen-fixing legumes such as lucerne may enhance soil N supply and therefore could be used in lucerne-wheat rotations. However, lucerne leys in this subtropical environment can create a soil moisture deficit, which may persist for a number of seasons. Therefore, we evaluated the effect of varying the duration of a lucerne ley (for up to 4 years) on soil N increase, N supply to wheat, soil water changes, wheat yields and wheat protein on a fertility-depleted Vertosol in a field experiment between 1989 and 1996 at Warra (26degrees 47'S, 150degrees53'E), southern Queensland. The experiment consisted of a wheat-wheat rotation, and 8 treatments of lucerne leys starting in 1989 (phase 1) or 1990 (phase 2) for 1,2,3 or 4 years duration, followed by wheat cropping. Lucerne DM yield and N yield increased with increasing duration of lucerne leys. Soil N increased over time following 2 years of lucerne but there was no further significant increase after 3 or 4 years of lucerne ley. Soil nitrate concentrations increased significantly with all lucerne leys and moved progressively downward in the soil profile from 1992 to 1995. Soil water, especially at 0.9-1.2 m depth, remained significantly lower for the next 3 years after the termination of the 4 year lucerne ley than under continuous wheat. No significant increase in wheat yields was observed from 1992 to 1995, irrespective of the lucerne ley. However, wheat grain protein concentrations were significantly higher under lucerne-wheat than under wheat wheat rotations for 3-5 years. The lucerne yield and soil water and nitrate-N concentrations were satisfactorily simulated with the APSIM model. Although significant N accretion occurred in the soil following lucerne leys, in drier seasons, recharge of the drier soil profile following long duration lucerne occurred after 3 years. Consequently, 3- and 4-year lucerne-wheat rotations resulted in more variable wheat yields than wheat-wheat rotations in this region. The remaining challenge in using lucerne-wheat rotations is balancing the N accretion benefits with plant-available water deficits, which are most likely to occur in the highly variable rainfall conditions of this region.