991 resultados para ALLELIC DIVERSITY


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Multiple Sclerosis (MS) is a central nervous system (CNS) chronic inflammatory demyelinating disease leading to various neurological disabilities. The disorder is more prevalent for women with a ratio of 3:2 female to male. Objectives: To investigate variation within the estrogen receptor 1 (ESR1) polymorphism gene in an Australian MS case-control population using two intragenic restriction fragment length polymorphisms; the G594A located in exon 8 detected with the BtgI restriction enzyme and T938C located in intron 1, detected with PvuII. One hundred and ten Australian MS patients were studied, with patients classified clinically as Relapsing Remitting MS (RR-MS), Secondary Progressive MS (SP-MS) or Primary Progressive MS (PP-MS). Also, 110 age, sex and ethnicity matched controls were investigated as a comparative group. No significant difference in the allelic distribution frequency was found between the case and control groups for the ESR1 PvuII (P = 0.50) and Btg1 (P = 0.45) marker. Our results do not support a role for these two ESR1 markers in multiple sclerosis susceptibility, however other markers within ESR1 should not be excluded for potential involvement in the disorder.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Migraine is a debilitating neurological disorder characterized by recurrent attacks of severe headache. The disorder is highly prevalent, affecting approximately 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the type and number of genes involved is not yet clear. However, the calcium channel gene, CACNA1A, on chromosome 19 contains mutations responsible for familial hemiplegic migraine, a rare and severe subtype of migraine. There is also evidence to suggest that serotonin- and dopamine-related genes may be involved in the pathogenesis of migraine. This study employed a linkage and association approach to investigate neurotransmitter-related migraine candidate genes. Polymorphisms within the dopamine beta-hydroxylase (DBH) gene, serotonin transporter gene (SERT), and dopamine receptor gene (DRD2) were tested in 177 unrelated Caucasian migraineurs and 182 control individuals. In addition, an independent sample of 82 families affected with migraine was examined. Unrelated case-control association analysis of a DBH intragenic dinucleotide polymorphism indicated altered allelic distribution between migraine and control groups (L2=16.53, P=0.019). Furthermore, the transmission/disequilibrium test, which was implemented on the family data, also indicated distortion of allele transmission for the same DBH marker (L2=4.44, P=0.035). Together, these results provide evidence for allelic association of the DBH gene with typical migraine susceptibility (Fisher's combined P value=0.006) and indicate that further research into the role of the DBH gene in the etiology of migraine is warranted.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The production of adequate agricultural outputs to support the growing human population places great demands on agriculture, especially in light of ever-greater restrictions on input resources. Sorghum is a drought-adapted cereal capable of reliable production where other cereals fail, and thus represents a good candidate to address food security as agricultural inputs of water and arable land grow scarce. A long-standing issue with sorghum grain is that it has an inherently lower digestibility. Here we show that a low-frequency allele type in the starch metabolic gene, pullulanase, is associated with increased digestibility, regardless of genotypic background. We also provide evidence that the beneficial allele type is not associated with deleterious pleiotropic effects in the modern field environment. We argue that increasing the digestibility of an adapted crop is a viable way forward towards addressing food security while maximizing water and land-use efficiency.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

For the past two decades the concept of managing individual difference in the workforce has been popular in many Western organizations, with calls to manage this "diversity" for the greater good of the organization and the\ individuals in it. Paradoxically, there is no agreed definition for this concept, and its description remains unclear and often contested (Jensen, Maznevski & Schneider 2011). Indeed, a range of terms is used, including diversity: diversity at work, managing diversity, diversity management, workplace diversity, productive diversity, and so forth. The foundation of the concept of managing diversity is the idea that an organization's workforce displays a range of “diverse” characteristics. The characteristics that are included under the heading Of "diversity" vary.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The inconsistent findings of past board diversity research demand a test of competing linear and curvilinear diversity–performance predictions. This research focuses on board age and gender diversity, and presents a positive linear prediction based on resource dependence theory, a negative linear prediction based on social identity theory, and an inverted U-shaped curvilinear prediction based on the integration of resource dependence theory with social identity theory. The predictions were tested using archival data on 288 large organizations listed on the Australian Securities Exchange, with a 1-year time lag between diversity (age and gender) and performance (employee productivity and return on assets). The results indicate a positive linear relationship between gender diversity and employee productivity, a negative linear relationship between age diversity and return on assets, and an inverted U-shaped curvilinear relationship between age diversity and return on assets. The findings provide additional evidence on the business case for board gender diversity and refine the business case for board age diversity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In vivo small molecules as necessary intermediates are involved in numerous critical metabolic pathways and biological processes associated with many essential biological functions and events. There is growing evidence that MS-based metabolomics is emerging as a powerful tool to facilitate the discovery of functional small molecules that can better our understanding of development, infection, nutrition, disease, toxicity, drug therapeutics, gene modifications and host-pathogen interaction from metabolic perspectives. However, further progress must still be made in MS-based metabolomics because of the shortcomings in the current technologies and knowledge. This technique-driven review aims to explore the discovery of in vivo functional small molecules facilitated by MS-based metabolomics and to highlight the analytic capabilities and promising applications of this discovery strategy. Moreover, the biological significance of the discovery of in vivo functional small molecules with different biological contexts is also interrogated at a metabolic perspective.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Many wild koala populations in Australia continue to experience serious declines due to factors such as disease caused by Chlamydia. This thesis is the first of its kind to investigate diversity of the chlamydial infections in wild koala populations across Australia and has made significant progress towards the development of a vaccine for koalas. The findings in this study have demonstrated that it is feasible to develop a safe and effective recombinant vaccine against Chlamydia in both disease free as well as severely diseased koalas. Most importantly, this study is also first of its kind to evaluate a multi-component vaccine that should be effective against the range of Chlamydia pecorum strains circulating in both captive as well as wild koala populations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background Dietary diversity is recognized as a key element of a high quality diet. However, diets that offer a greater variety of energy-dense foods could increase food intake and body weight. The aim of this study was to explore association of diet diversity with obesity in Sri Lankan adults. Methods Six hundred adults aged > 18 years were randomly selected by using multi-stage stratified sample. Dietary intake assessment was undertaken by a 24 hour dietary recall. Three dietary scores, Dietary Diversity Score (DDS), Dietary Diversity Score with Portions (DDSP) and Food Variety Score (FVS) were calculated. Body mass index (BMI) ≥ 25 kg.m-2 is defined as obese and Asian waist circumference cut-offs were used diagnosed abdominal obesity. Results Mean of DDS for men and women were 6.23 and 6.50 (p=0.06), while DDSP was 3.26 and 3.17 respectively (p=0.24). FVS values were significantly different between men and women 9.55 and 10.24 (p=0.002). Dietary diversity among Sri Lankan adults was significantly associated with gender, residency, ethnicity, education level but not with diabetes status. As dietary scores increased, the percentage consumption was increased in most of food groups except starches. Obese and abdominal obese adults had the highest DDS compared to non obese groups (p<0.05). With increased dietary diversity the level of BMI, waist circumference and energy consumption was significantly increased in this population. Conclusion Our data suggests that dietary diversity is positively associated with several socio-demographic characteristics and obesity among Sri Lankan adults. Although high dietary diversity is widely recommended, public health messages should emphasize to improve dietary diversity in selective food items.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Putnam's “constrict theory” suggests that ethnic diversity creates challenges for developing and sustaining social capital in urban settings. He argues that diversity decreases social cohesion and reduces social interactions among community residents. While Putnam's thesis is the subject of much debate in North America, the United Kingdom, and Europe, there is a limited focus on how ethnic diversity impacts upon social cohesion and neighborly exchange behaviors in Australia. Employing multilevel modeling and utilizing administrative and survey data from 4,000 residents living in 148 Brisbane suburbs, we assess whether ethnic diversity lowers social cohesion and increases “hunkering.” Our findings indicate that social cohesion and neighborly exchange are attenuated in ethnically diverse suburbs. However, diversity is less consequential for neighborly exchange among immigrants when compared to the general population. Our results provide at least partial support for Putnam's thesis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we define two models of users that require diversity in search results; these models are theoretically grounded in the notion of intrinsic and extrinsic diversity. We then examine Intent-Aware Expected Reciprocal Rank (ERR-IA), one of the official measures used to assess diversity in TREC 2011-12, with respect to the proposed user models. By analyzing ranking preferences as expressed by the user models and those estimated by ERR-IA, we investigate whether ERR-IA assesses document rankings according to the requirements of the diversity retrieval task expressed by the two models. Empirical results demonstrate that ERR-IA neglects query-intents coverage by attributing excessive importance to redundant relevant documents. ERR-IA behavior is contrary to the user models that require measures to first assess diversity through the coverage of intents, and then assess the redundancy of relevant intents. Furthermore, diversity should be considered separately from document relevance and the documents positions in the ranking.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Australia has been populated for more than 40,000 years with Indigenous Australians joined by European settlers only 230 years ago. The first settlers consisted of convicts from more than 28 countries and members of the British army who arrived in 1788 to establish a British penal colony. Mass migration in the nineteenth century with one and a half million immigrants from Europe, principally from the United Kingdom and Ireland (Haines and Shlomowitz, 1992), established the continent as an Anglo society in the Pacific. In the twentieth century immigrants came from many European countries and in the latter decades from many parts of Asia and the Middle East (Collins, 1991, pp.10-13). In the 21st century Australia has an ethnically and culturally diverse population. The original Indigenous population of Australia accounts for approximately 460,000 or 2.5 per cent of the total population (ABS, 2006a). Estimates are that around 4.5m. persons in the population (close to 20 per cent), were born outside Australia with the majority of these arriving from Europe, principally the United Kingdom, and New Zealand (ABS, 2006b). Like many other countries, Australia has a legacy of discrimination and inequality in employment. Propelled by racist ideologies and the male breadwinner ideology, Indigenous Australians, and non-European immigrants, and women were barred from certain jobs and paid less for their work than any white male counterpart. These conditions were legally sanctioned through the industrial relations system and other laws in the nineteenth and first half of the twentieth century. Since the 1960s a dramatic change has occurred in social policy and national legislation and Australia today has an extensive array of laws which forbid employment discrimination on race, ethnicity, gender and many other characteristics, and other approaches which promote proactive organizational plans and actions to achieve equity in employment. This chapter outlines these developments.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Polarisation diversity is a technique to improve the quality of mobile communications, but its reliability is suboptimal because it depends on the mobile channel and the antenna orientations at both ends of the mobile link. A method to optimise the reliability is established by minimising the dependency on antenna orientations. While the mobile base station can have fixed antenna orientation, the mobile terminal is typically a handheld device with random orientations. This means orientation invariance needs to be established at the receiver in the downlink, and at the transmitter in the uplink. This research presents separate solutions for both cases, and is based on the transmission of an elliptically polarised signal synthesised from the channel statistics. Complete receiver orientation invariance is achieved in the downlink. Effects of the transmitter orientation are minimised in the uplink.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article examines how documentation concealed racialising practices in a diversity project that was seen to be productive and inclusive. Documentation examples are taken from a doctoral study about embedding Indigenous perspectives in early childhood education curricula in two Australian urban childcare centres. In place of reporting examples of ‘good’ early childhood education practice, the study labelled racialising practices in educators’ work. The primary aim was to understand how racialising practices are mobilised in professional practices, including documentation, even when educators’ work is seen to be high quality. Extracts from two communal journals that captured an action research process around embedding practices are examined to show how racism and whiteness were concealed within the documentation. This enables understanding about how documentation can provide evidence to stakeholders that diversity work in mainstream childcare centres is productive and inclusive, despite disparity between what is recorded and what occurs in practice.