1000 resultados para Implications
Resumo:
Head motion (HM) is a well known confound in analyses of functional MRI (fMRI) data. Neuroimaging researchers therefore typically treat HM as a nuisance covariate in their analyses. Even so, it is possible that HM shares a common genetic influence with the trait of interest. Here we investigate the extent to which this relationship is due to shared genetic factors, using HM extracted from resting-state fMRI and maternal and self report measures of Inattention and Hyperactivity-Impulsivity from the Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour (SWAN) scales. Our sample consisted of healthy young adult twins (N = 627 (63% females) including 95 MZ and 144 DZ twin pairs, mean age 22, who had mother-reported SWAN; N = 725 (58% females) including 101 MZ and 156 DZ pairs, mean age 25, with self reported SWAN). This design enabled us to distinguish genetic from environmental factors in the association between head movement and ADHD scales. HM was moderately correlated with maternal reports of Inattention (r = 0.17, p-value = 7.4E-5) and Hyperactivity-Impulsivity (r = 0.16, p-value = 2.9E-4), and these associations were mainly due to pleiotropic genetic factors with genetic correlations [95% CIs] of rg = 0.24 [0.02, 0.43] and rg = 0.23 [0.07, 0.39]. Correlations between self-reports and HM were not significant, due largely to increased measurement error. These results indicate that treating HM as a nuisance covariate in neuroimaging studies of ADHD will likely reduce power to detect between-group effects, as the implicit assumption of independence between HM and Inattention or Hyperactivity-Impulsivity is not warranted. The implications of this finding are problematic for fMRI studies of ADHD, as failing to apply HM correction is known to increase the likelihood of false positives. We discuss two ways to circumvent this problem: censoring the motion contaminated frames of the RS-fMRI scan or explicitly modeling the relationship between HM and Inattention or Hyperactivity-Impulsivity
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- Background Following Kapur’s hypothesis [1] that schizophrenia is the intensification of phenomenological experience caused by the upregulation of dopamine, a survey of observed dopamine responses to phenomenal information was conducted. - Method An integrative study. - Results When considered in the light of the ecological theory of perception (ETP) [2] and global workspace theory (GBT) [3] Kapur’s hypothesis makes sense: Both the ETP and the GBT require an agent to attribute salience to perceptual information in order to filter an infinite array of available information and usefully sort information by importance. Dopamine may be the primary agent for this purpose. Thus perception itself is suspected as being a dopamine-mediated, and the symptoms and signs of schizophrenia may therefore be the result of dopamine dysfunction. - Conclusions The application of both ETP and GBT to the dopamine hypothesis gives the hypothesis a much-needed causal mechanism and the confl uence of these theories also provides ETP with a neurological perceptual fi lter. This paper provides a compelling model for schizophrenia; a hypothesis that ties perceptual theory to Kapur ’ s concept of dopamine-mediated salience.
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The study investigated variation in the ways in which a group of students and teachers of Evangelical Lutheran religious education in Finnish upper secondary schools understand Lutheranism and searched for educational implications for learning in religious education. The aim of understanding the qualitative variation in understanding Lutheranism was explored through the relationship between the following questions, which correspond to the results reported in the following original refereed publications: 1) How do Finnish students understand Lutheranism? 2) How do Finnish teachers of religious education constitute the meaning of Lutheranism? 3) How could phenomenography and the Variation Theory of Learning contribute to learning about and from religion in the context of Finnish Lutheran Religious Education as compared to religious education in the UK? Two empirical studies (Hella, 2007; Hella, 2008) were undertaken from a phenomenographic research perspective (e.g., Marton, 1981) and the Variation Theory of Learning (e.g., Marton & Tsui et al. 2004) that developed from it. Data was collected from 63 upper secondary students and 40 teachers of religious education through written tasks with open questions and complementary interviews with 11 students and 20 teachers for clarification of meanings. The two studies focused on the content and structure of meaning discernment in students and teachers expressed understandings of Lutheranism. Differences in understandings are due to differences in the meanings that are discerned and focused on. The key differences between the ways students understand varied from understanding Lutheranism as a religion to personal faith with its core in mercy. The logical relationships between the categories that describe variation in understanding express a hierarchy of ascending complexity, according to which more developed understandings are inclusive of less developed ones. The ways the teachers understand relate to student s understandings in a sequential manner. Phenomenography and Variation Theory were discussed in the context of religious education in Finland and the UK in relation to the theoretical notion of learning about and from religion (Hella & Wright, 2008). The thesis suggests that variation theory enables religious educators to recognise the unity of learning about and from religion, as learning is always learning about something and involves simultaneous engagement with the object of learning and development as a person. The study also suggests that phenomenography and variation theory offer a means by which it is possible for academics, policy makers, curriculum designers, teachers and students to learn to discern different ways of understanding the contested nature of religions. Keywords: Lutheranism, understanding, variation, teaching, learning, phenomenography, religious education
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The role of added sugar in a healthy diet and implications for health inequalities Sugars provide a readily available, inexpensive source of energy, can increase palatability and help preserve some foods. However added sugars also dilute the nutrient density of the diet. Further, consumption of sugar-sweetened beverages is associated with increased risk of weight gain and reduced bone strength, and high or frequent consumption of added sugars is associated with increased risk of dental caries, particularly in infants and young children. The products of the 2013 NHMRC Dietary Guidelines work program at www.eatforhealth.gov.au include the comprehensive evidence base about food, diet and health relationships and the dietary modeling used to inform recommendations. This presentation will detail the scientific evidence underpinning the revised dietary recommendations on consumption of foods and drinks containing added sugar and compare recommendations with the most recently available relevant Australian dietary intake and trend data. Differences in intakes of relevant food and drinks across quintiles of social disadvantage and in particular between Aboriginal and Torres Strait Islander groups and non-Indigenous Australians will also be explored.
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Physicochemical characterization of freshwater samples from Finland, Sweden, the Netherlands, and Spain revealed that water hardness and pH decreased and the quantity and quality of humic substances changed considerably in this geographical series from south to north. Since the ambient water chemistry may affect the availability of chemicals, the total aqueous concentration of a chemical may be insufficient to predict the bioconcentration, subsequent biological response, and thus risk. In addition, organisms could be affected directly by water quality characteristics. In this context the main objective of this thesis was to investigate the bioavailability of selected ecotoxicologically relevant chemicals (cadmium, benzo(a)pyrene, and pyrene) in various European surface waters and to show the importance of certain water chemistry characteristics in interpreting the bioavailability and toxicity results. The bioavailability of cadmium to Daphnia magna was examined in very soft humic lake water. Humic substances as natural ligands decreased the free and bioavailable proportion of cadmium in soft lake water. As a consequence the uptake rate and the acute toxicity decreased compared with the humic-free reference. When the hardness of humic lake water was artificially elevated, the acute toxicity of cadmium decreased, although the proportion of free cadmium increased. The decreased bioavailability of cadmium in hard water was a result of effective competition for uptake by the hardness cations, especially calcium ions. The protective role of humic substances and water hardness against cadmium toxicity was also observed in Lumbriculus variegatus, although D. magna was more sensitive to cadmium. The bioavailability of two polycyclic aromatic hydrocarbons (PAHs), pyrene and benzo(a)pyrene, was studied in European surface waters of varying water chemistry. Humic substances acted as complexing ligands with both PAHs, but the bioavailability of the more lipophilic benzo(a)pyrene to D. magna was affected more by humic substances than that of pyrene. In addition, not only the quantity of humic substances, but also their quality affected the bioavailability of benzo(a)pyrene. Nevertheless, the humic substances played a protective role in the photo-enhanced toxicity of pyrene under UV-B radiation. Water hardness had no effect on pyrene toxicity. Results indicate that the typical physicochemical characteristics of boreal freshwaters should be considered carefully in local and regional risk assessment of chemicals concerning the Fennoscandian region.
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Globalization, along with its digital and information communication technology counterparts, including the Internet and cyberspace, may signify a whole new era for human rights, characterized by new tensions, challenges, and risks for human rights, as well as new opportunities. Human Rights and Risks in the Digital Era: Globalization and the Effects of Information Technologies explores the emergence and evolution of ‘digital’ rights that challenge and transform more traditional legal, political, and historical understandings of human rights. Academic and legal scholars will explore individual, national, and international democratic dilemmas--sparked by economic and environmental crises, media culture, data collection, privatization, surveillance, and security--that alter the way individuals and societies think about, regulate, and protect rights when faced with new challenges and threats. The book not only uncovers emerging changes in discussions of human rights, it proposes legal remedies and public policies to mitigate the challenges posed by new technologies and globalization.
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Background: The Mycobacterium leprae genome has less than 50% coding capacity and 1,133 pseudogenes. Preliminary evidence suggests that some pseudogenes are expressed. Therefore, defining pseudogene transcriptional and translational potentials of this genome should increase our understanding of their impact on M. leprae physiology. Results: Gene expression analysis identified transcripts from 49% of all M. leprae genes including 57% of all ORFs and 43% of all pseudogenes in the genome. Transcribed pseudogenes were randomly distributed throughout the chromosome. Factors resulting in pseudogene transcription included: 1) co-orientation of transcribed pseudogenes with transcribed ORFs within or exclusive of operon-like structures; 2) the paucity of intrinsic stem-loop transcriptional terminators between transcribed ORFs and downstream pseudogenes; and 3) predicted pseudogene promoters. Mechanisms for translational ``silencing'' of pseudogene transcripts included the lack of both translational start codons and strong Shine-Dalgarno (SD) sequences. Transcribed pseudogenes also contained multiple ``in-frame'' stop codons and high Ka/Ks ratios, compared to that of homologs in M. tuberculosis and ORFs in M. leprae. A pseudogene transcript containing an active promoter, strong SD site, a start codon, but containing two in frame stop codons yielded a protein product when expressed in E. coli. Conclusion: Approximately half of M. leprae's transcriptome consists of inactive gene products consuming energy and resources without potential benefit to M. leprae. Presently it is unclear what additional detrimental affect(s) this large number of inactive mRNAs has on the functional capability of this organism. Translation of these pseudogenes may play an important role in overall energy consumption and resultant pathophysiological characteristics of M. leprae. However, this study also demonstrated that multiple translational ``silencing'' mechanisms are present, reducing additional energy and resource expenditure required for protein production from the vast majority of these transcripts.
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The complete genome of the baker's yeast S. cerevisiae was analyzed for the presence of polypurine/polypyrimidine (poly[pu/py]) repeats and their occurrences were classified on the basis of their location within and outside open reading frames (ORFs). The analysis reveals that such sequence motifs are present abundantly both in coding as well as noncoding regions. Clear positional preferences are seen when these tracts occur in noncoding regions. These motifs appear to occur predominantly at a unit nucleosomal length both upstream and downstream of ORFs. Moreover, there is a biased distribution of polypurines in the coding strands when these motifs occur within open reading frames. The significance of the biased distribution is discussed with reference to the occurrence of these motifs in other known mRNA sequences and expressed sequence tags. A model for cis regulation of gene expression is proposed based on the ability of these motifs to form an intermolecular triple helix structure when present within the coding region and/or to modulate nucleosome positioning via enhanced histone affinity when present outside coding regions.
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We report cloning of the DNA encoding winged bean basic agglutinin (WBA I). Using oligonucleotide primers corresponding to N- and C-termini of the mature lectin, the complete coding sequence for WBA I could be amplified from genomic DNA. DNA sequence determination by the chain termination method revealed the absence of any intervening sequences in the gene. The DNA deduced amino acid sequence of WBA I displayed some differences with its primary structure established previously by chemical means. Comparison of the sequence of WBA I with that of other legume lectins highlighted several interesting features, including the existence of the largest specificity determining loop which might account for its oligosaccharide-binding specificity and the presence of an additional N-glycosylation site. These data also throw some light on the relationship between the primary structure of the protein and its probable mode of dimerization.
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Health information technology (IT) can have a profound effect on the temporal flow and organisation of work. Yet research into the context, meaning and significance of temporal factors remains limited, most likely because of its complexity. This study outlines the role of communications in the context of the temporal and organizational landscape of seven Australian residential aged care facilities displaying a range of information exchange practices and health IT capacity. The study used qualitative and observational methods to identify temporal factors associated with internal and external modes of communication across the facilities and to explore the use of artifacts. The study concludes with a depiction of the temporal landscape of residential aged care particularly in regards to the way that work is allocated, prioritized, sequenced and coordinated. We argue that the temporal landscape involves key context-sensitive factors that are critical to understanding the way that humans accommodate to, and deal with health technologies, and which are therefore important for the delivery of safe and effective care.
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This thesis is a qualitative study that examines how participating staff from Thai based non-governmental organisations interpret and construct the notion of human trafficking; and how this impacts prevention methods. The research examined the impact of different socio-cultural, political and religious ideologies on anti-trafficking prevention and programme implementation. Findings highlighted that while a 'raid and rescue' approach to human trafficking was widely recognised by donors and the media; it was not suitable or complementary to sustainable and community focused anti-trafficking models. Rather, a holistic approach that considers contextual factors and inter-agency collaboration is essential for effective anti-trafficking prevention strategies.
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The influence of atmospheric aerosols on Earth's radiation budget and hence climate, though well recognized and extensively investigated in recent years, remains largely uncertain mainly because of the large spatio-temporal heterogeneity and the lack of data with adequate resolution. To characterize this diversity, a major multi-platform field campaign ICARB (Integrated Campaign for Aerosols, gases and Radiation Budget) was carried out during the pre-monsoon period of 2006 over the Indian landmass and surrounding oceans, which was the biggest such campaign ever conducted over this region. Based on the extensive and concurrent measurements of the optical and physical properties of atmospheric aerosols during ICARB, the spatial distribution of aerosol radiative forcing was estimated over the entire Bay of Bengal (BoB), northern Indian Ocean and Arabian Sea (AS) as well as large spatial variations within these regions. Besides being considerably lower than the mean values reported earlier for this region, our studies have revealed large differences in the forcing components between the BoB and the AS. While the regionally averaged aerosol-induced atmospheric forcing efficiency was 31 +/- 6 W m(-2) tau(-1) for the BoB, it was only similar to 18 +/- 7 W m(-2) tau(-1) for the AS. Airborne measurements revealed the presence of strong, elevated aerosol layers even over the oceans, leading to vertical structures in the atmospheric forcing, resulting in significant warming in the lower troposphere. These observations suggest serious climate implications and raise issues ranging from the impact of aerosols on vertical thermal structure of the atmospheric and hence cloud formation processes to monsoon circulation.
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Recent molecular studies on langurs of the Indian subcontinent suggest that the widely-distributed and morphologically variable Hanuman langurs (Semnopithecus entellus) are polyphyletic with respect to Nilgiri and urple-faced langurs. To further investigate this scenario, we have analyzed additional sequences of mitochondrial cytochrome b as well as nuclear protamine P1 genes from these species. The results confirm Hanuman langur polyphyly in the mitochondrial tree and the nuclear markers suggest that the Hanuman langurs share protamine P1 alleles with Nilgiri and purple-faced langurs. We recommend provisional splitting of the so-called Hanuman langurs into three species such that the taxonomy is consistent with their evolutionary relationships.