843 resultados para Authors, Spanish American.


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Barley yellow dwarf luteovirus-GPV (BYDV-GPV) is a common problem in Chinese wheat crops but is unrecorded elsewhere. A defining characteristic of GPV is its capacity to be transmitted efficiently by both Schizaphis graminum and Rhopaloshiphum padi. This dual aphid species transmission contrasts with those of BYDV-RPV and BYDV-SGV, globally distributed viruses, which are efficiently transmitted only by Rhopaloshiphum padi and Schizaphis graminum respectively. The viral RNA sequences encoding the coat protein (22K) gene, the movement protein (17K) gene, the region surrounding the conserved GDD motif of the polymerase gene and the intergenic sequences between these genes were determined for GPV and an Australian isolate of BYDV-RPV (RPVa). In all three genes, the sequences of GPV and RPVa were more similar to those of an American isolate of BYDV-RPV (RPVu) than to any other luteovirus for which there is data available. RPVa and RPVu were very similar, especially their coat proteins which had 97% identity at the amino acid level. The coat protein of GPV had 76% and 78% amino acid identity with RPVa and RPVu respectively. The data suggest that RPVu and RPVa are correctly named as strains of the same serotype and that GPV is sufficiently different from either RPV strain to be considered a distinct BYDV type. The coat protein and movement protein genes of GPV are very dissimilar to SGV. The polymerase sequences of RPVu, RPVa and GPV show close affinities with those of the sobemo-like luteoviruses and little similarity with those of the carmo-like luteoviruses. The sequences of the coat proteins, movement proteins and the polymerase segments of BYDV serotypes, other than RPV and GPV, form a cluster that is separate from their counterpart sequences from dicot-infecting luteoviruses. The RPV and GPV isolates consistently fall within a dicot-infecting cluster. This suggests that RPV and GPV evolved from within this group of viruses. Since these other viruses all infect dicots it seems likely that their common ancestor infected a dicot and that RPV and GPV evolved from a virus that switched hosts from a dicot to a monocot.

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Purpose: This study investigated the effect of chemical conjugation of the amino acid L-leucine to the polysaccharide chitosan on the dispersibility and drug release pattern of a polymeric nanoparticle (NP)-based controlled release dry powder inhaler (DPI) formulation. Methods: A chemical conjugate of L-leucine with chitosan was synthesized and characterized by Infrared (IR) Spectroscopy, Nuclear Magnetic Resonance (NMR) Spectroscopy, Elemental Analysis and X-ray Photoelectron Spectroscopy (XPS). Nanoparticles of both chitosan and its conjugate were prepared by a water-in-oil emulsification – glutaraldehyde cross-linking method using the antihypertensive agent, diltiazem (Dz) hydrochloride as the model drug. The surface morphology and particle size distribution of the nanoparticles were determined by Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS). The dispersibility of the nanoparticle formulation was analysed by a Twin Stage Impinger (TSI) with a Rotahaler as the DPI device. Deposition of the particles in the different stages was determined by gravimetry and the amount of drug released was analysed by UV spectrophotometry. The release profile of the drug was studied in phosphate buffered saline at 37 ⁰C and analyzed by UV spectrophotometry. Results: The TSI study revealed that the fine particle fractions (FPF), as determined gravimetrically, for empty and drug-loaded conjugate nanoparticles were significantly higher than for the corresponding chitosan nanoparticles (24±1.2% and 21±0.7% vs 19±1.2% and 15±1.5% respectively; n=3, p<0.05). The FPF of drug-loaded chitosan and conjugate nanoparticles, in terms of the amount of drug determined spectrophotometrically, had similar values (21±0.7% vs 16±1.6%). After an initial burst, both chitosan and conjugate nanoparticles showed controlled release that lasted about 8 to 10 days, but conjugate nanoparticles showed twice as much total drug release compared to chitosan nanoparticles (~50% vs ~25%). Conjugate nanoparticles also showed significantly higher dug loading and entrapment efficiency than chitosan nanoparticles (conjugate: 20±1% & 46±1%, chitosan: 16±1% & 38±1%, n=3, p<0.05). Conclusion: Although L-leucine conjugation to chitosan increased dispersibility of formulated nanoparticles, the FPF values are still far from optimum. The particles showed a high level of initial burst release (chitosan, 16% and conjugate, 31%) that also will need further optimization.

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Collaborative infrastructure projects use hybrid formal and informal governance structures to manage transactions. Based on previous desk-top research, the authors identified the key mechanisms underlying project governance, and posited the performance implications of the governance (Chen et al. 2012). The current paper extends that qualitative research by testing the veracity of those findings using data from 320 Australian construction organisations. The results provide, for the first time, reliable and valid scales to measure governance and performance of collaborative projects, and the relationship between them. The results confirm seven of seven hypothesised governance mechanisms; 30 of 43 hypothesised underlying actions; eight of eight hypothesised key performance indicators; and the dual importance of formal and informal governance. A startling finding of the study was that the implementation intensity of informal mechanisms (non-contractual conditions) is a greater predictor of project performance variance than that of formal mechanisms (contractual conditions). Further, contractual conditions do not directly impact project performance; instead their impact is mediated by the non-contractual features of a project. Obligations established under the contract are not sufficient to optimise project performance.

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Big Data presents many challenges related to volume, whether one is interested in studying past datasets or, even more problematically, attempting to work with live streams of data. The most obvious challenge, in a ‘noisy’ environment such as contemporary social media, is to collect the pertinent information; be that information for a specific study, tweets which can inform emergency services or other responders to an ongoing crisis, or give an advantage to those involved in prediction markets. Often, such a process is iterative, with keywords and hashtags changing with the passage of time, and both collection and analytic methodologies need to be continually adapted to respond to this changing information. While many of the data sets collected and analyzed are preformed, that is they are built around a particular keyword, hashtag, or set of authors, they still contain a large volume of information, much of which is unnecessary for the current purpose and/or potentially useful for future projects. Accordingly, this panel considers methods for separating and combining data to optimize big data research and report findings to stakeholders. The first paper considers possible coding mechanisms for incoming tweets during a crisis, taking a large stream of incoming tweets and selecting which of those need to be immediately placed in front of responders, for manual filtering and possible action. The paper suggests two solutions for this, content analysis and user profiling. In the former case, aspects of the tweet are assigned a score to assess its likely relationship to the topic at hand, and the urgency of the information, whilst the latter attempts to identify those users who are either serving as amplifiers of information or are known as an authoritative source. Through these techniques, the information contained in a large dataset could be filtered down to match the expected capacity of emergency responders, and knowledge as to the core keywords or hashtags relating to the current event is constantly refined for future data collection. The second paper is also concerned with identifying significant tweets, but in this case tweets relevant to particular prediction market; tennis betting. As increasing numbers of professional sports men and women create Twitter accounts to communicate with their fans, information is being shared regarding injuries, form and emotions which have the potential to impact on future results. As has already been demonstrated with leading US sports, such information is extremely valuable. Tennis, as with American Football (NFL) and Baseball (MLB) has paid subscription services which manually filter incoming news sources, including tweets, for information valuable to gamblers, gambling operators, and fantasy sports players. However, whilst such services are still niche operations, much of the value of information is lost by the time it reaches one of these services. The paper thus considers how information could be filtered from twitter user lists and hash tag or keyword monitoring, assessing the value of the source, information, and the prediction markets to which it may relate. The third paper examines methods for collecting Twitter data and following changes in an ongoing, dynamic social movement, such as the Occupy Wall Street movement. It involves the development of technical infrastructure to collect and make the tweets available for exploration and analysis. A strategy to respond to changes in the social movement is also required or the resulting tweets will only reflect the discussions and strategies the movement used at the time the keyword list is created — in a way, keyword creation is part strategy and part art. In this paper we describe strategies for the creation of a social media archive, specifically tweets related to the Occupy Wall Street movement, and methods for continuing to adapt data collection strategies as the movement’s presence in Twitter changes over time. We also discuss the opportunities and methods to extract data smaller slices of data from an archive of social media data to support a multitude of research projects in multiple fields of study. The common theme amongst these papers is that of constructing a data set, filtering it for a specific purpose, and then using the resulting information to aid in future data collection. The intention is that through the papers presented, and subsequent discussion, the panel will inform the wider research community not only on the objectives and limitations of data collection, live analytics, and filtering, but also on current and in-development methodologies that could be adopted by those working with such datasets, and how such approaches could be customized depending on the project stakeholders.

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In the present study, we examined the associations of early nutrition with adult lean body mass (LBM) and muscle strength in a birth cohort that was established to assess the long-term impact of a nutrition program. Participants (n = 1,446, 32% female) were born near Hyderabad, India, in 29 villages from 1987 to 1990, during which time only intervention villages (n = 15) had a government program that offered balanced protein-calorie supplementation to pregnant women and children. Participants’ LBM and appendicular skeletal muscle mass were measured using dual energy x-ray absorptiometry; grip strength and information on lifestyle indicators, including diet and physical activity level, were also obtained. Ages (mean = 20.3 years) and body mass indexes (weight (kg)/height (m)2; mean = 19.5) of participants in 2 groups were similar. Current dietary energy intake was higher in the intervention group. Unadjusted LBM and grip strength were similar in 2 groups. After adjustment for potential confounders, the intervention group had lower LBM (β = −0.75; P = 0.03), appendicular skeletal muscle mass, and grip strength than did controls, but these differences were small in magnitude (<0.1 standard deviation). Multivariable regression analyses showed that current socioeconomic position, energy intake, and physical activity level had a positive association with adult LBM and muscle strength. This study could not detect a “programming” effect of early nutrition supplementation on adult LBM and muscle strength.

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Community foundations have been described as the fastest growing form of philantrhopy. This report focuses on the development of community foundations in Australia as one especially important example of the growth of community foundations world-wide.

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Recently, we defined a new syndromic form of X-linked mental retardation in a 4-generation family with a unique clinical phenotype characterized by mild mental retardation, choreoathetosis, and abnormal behavior (MRXS10). Linkage analysis in this family revealed a candidate region of 13.4 Mb between markers DXS1201 and DXS991 on Xp11; therefore, mutation analysis was performed by direct sequencing in most of the 135 annotated genes located in the region. The gene (HADH2) encoding L-3-hydroxyacyl-CoA dehydrogenase II displayed a sequence alteration (c.574 C-->A; p.R192R) in all patients and carrier females that was absent in unaffected male family members and could not be found in 2,500 control X chromosomes, including in those of 500 healthy males. The silent C-->A substitution is located in exon 5 and was shown by western blot to reduce the amount of HADH2 protein by 60%-70% in the patient. Quantitative in vivo and in vitro expression studies revealed a ratio of splicing transcript amounts different from those normally seen in controls. Apparently, the reduced expression of the wild-type fragment, which results in the decreased protein expression, rather than the increased amount of aberrant splicing fragments of the HADH2 gene, is pathogenic. Our data therefore strongly suggest that reduced expression of the HADH2 protein causes MRXS10, a phenotype different from that caused by 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency, which is a neurodegenerative disorder caused by missense mutations in this multifunctional protein.

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In 2006, the American Law Institute (ALI) and the International Insolvency Institute (III) established a Transnational Insolvency Project and appointed Professor Ian Fletcher (United Kingdom) and Professor Bob Wessels (Netherlands) as Joint Reporters. The objective was to investigate whether the essential provisions of the ALI Principles of Cooperation among the NAFTA Countries (ALI-NAFTA Principles) and the annexed Guidelines Applicable to Court-to-Court Communication in Cross-border Cases (ALI-NAFTA Guidelines) may, with certain necessary modifications, be acceptable for use by jurisdictions across the world. In 2012, Professor Fletcher and Professor Wessels presented the report Transnational Insolvency: Global Principles for Cooperation in International Insolvency Cases (“ALI-III Report”) to the Annual Meetings of the American Law Institute and the International Insolvency Institute. In 2013, the Australian Academy of Law (AAL) provided support to the authors to undertake research on the possible benefits for Australia of courts and insolvency administrators of referring to the ALI-III Report when addressing international insolvency cases. This AAL project was at the request of the Council of Chief Justices of Australia and New Zealand. This research Report compares the Global Principles for Cooperation in International Insolvency Cases with the Cross-border Insolvency Act 2008 and the UNCITRAL Model Law as it has been adopted and has force of law in Australia. Further, it examines the Global Guidelines for Court-to-Court Communications in International Insolvency Cases in light of Australian cross-border insolvency and procedural law. Finally, it makes brief reference to and commentary on the Global Rules on Conflict–of-Laws Matters in International Insolvency Cases annexed to the ALI-III Report from the perspective of Australian choice of law rules.

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This paper offers insights into the relationship between curriculum decision making, positive school climate, and academic achievement for same-sex attracted (SSA) students. The authors use critical discourse analysis to present a ‘conversation’ between six same-sex attracted young people, aged 14-19, and three pop-culture texts currently popular with both teachers and school-aged peers: The Hunger Games, Tomorrow When the War Began, and Neighbours. Analysis starts from the perspective that schools are empowered agents in the production of students’ sexualised identities and seeks to understand how textual choices function as active discourse in that production. Through this analysis, an argument is made for expanding notions of what it means to ‘attend to’ gender and sexuality through textual choice and critical pedagogy.

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A total of 1,625 tornadoes occurred in the United States in 2011, resulting in economic losses that exceeded $25 billion. Two tornado outbreaks stand out because they caused more than half of those losses. The tornadoes that cut through Tuscaloosa, Alabama, on April 27 and Joplin, Missouri, on May 22 were responsible for a combined 223 fatalities and more than 13,000 damaged buildings in the two cities. Although the economic losses associated with tornado damage are well documented, the writers argue that the overall impact should encompass longer term, broader considerations such as the social disruption and psychological effects that impact communities. This paper examines observations by tornado damage assessment teams led by the first author in these two medium-sized cities and suggests that the evolution of building codes and past approaches to construction have led to conditions that made this extent of damage possible. The authors outline a multidisciplinary path forward that incorporates engineering research and social and economic studies into a new design paradigm leading to building code changes and social practices that will improve resistance and mitigate future losses at a community level from tornadoes.

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Radiative and total heat transfer at the flow stagnation point of a 1:40.8 binary scaled model of the Titan Explorer vehicle were measured in the X3 expansion tube. Results from the current study illustrated that with the addition of CH4 into a N2 test gas radiative heat transfer could be detected. For a test gas of 5% CH4 and 95% N2, simulating an atmospheric model for Titanic aerocapture, approximately 4% of the experimentally measured total stagnation point heat transfer was found to be due to radiation. This was in comparison to < 1% measured for a test gas of pure nitrogen. When scaled to the flight vehicle, experimental results indicate a 64% contribution of radiation (test gas 5% CH4/95% N2). Previous numerical results however have predicted this contribution to be between 80-92%. Thus, experimental results from the current study suggest that numerical analyses are over-predicting the radiative heat transfer on the flight vehicle.

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The design-build (DB) system is regarded as an effective means of delivering sustainable buildings. Specifying clear sustainability requirements to potential contractors is of great importance to project success. This research investigates the current state-of-the-practice for the definition of sustainability requirements within the public sectors of the U.S. construction market using a robust content analysis of 49 DB requests for proposals (RFPs). The results reveal that owners predominantly communicate their desired level of sustainability through the LEED certification system. The sustainability requirement has become an important dimension for the best-value evaluation of DB contractors with specific importance weightings of up to 25%. Additionally, owners of larger projects and who provide less design information in their RFPs generally allocate significantly higher importance weightings to sustainability requirements. The primary knowledge contribution of this study to the construction industry is the reveal of current trend in DB procurement for green projects. The findings also provide owners, architects, engineers, and constructors with an effective means of communicating sustainability objectives in solicitation documents.

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I live in the Sydney North Shore suburb of Northbridge. In many ways it is a white middle class enclave, comparable to places like Cabramatta that are identified with a specifically represented ethnic group. Gated primarily by the inflated property prices, it is a location that marks a territory principally for the white middle class. It is not a place of African-American movements. Or is it? Radio, television, film and Internet increasingly constitute a large portion of the sonic and visual landscapes of our suburban lives. In our lounge rooms and in our cars we are presented texts that take us beyond our local environments, into the places of other nations. This paper will explore the position of a fan of rap music, physically located beyond the cultural and political circumstances that drive sustained action for the movements of African-Americans. It will analyze whether such a fandom can indicate membership, as a social actor, in this group and in doing so illuminate the boundaries of movement activity in an information society.

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This study compared the determinants of physical activity in active and low-active African-American sixth grade students (N=108, 57 F, 51 M). Objective assessments of physical activity over a seven-day period were obtained using the CSA 7164 accelerometer. Students were classified as active if they exhibited three pr more 20-minute bouts of moderate to vigorous physical activity over the seven-day period. Relative to low-actives, active boys reported significantly higher levels of self-efficacy, greater involvement in community physical activity organizations, and were significantly more likely to perceive their mother us active. Relative to low-actives, active girls reported significantly higher levels of physical activity self-efficacy, greater positive beliefs regarding physical activity outcomes, and were significantly less likely to watch television or play video games for greater than or equal to 3 hrs/day. These observations provide preliminary guidance as to the design of physical activity interventions targeted at African-American youth.

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Many countries conduct regular national time use surveys, some of which date back as far as the 1960s. Time use surveys potentially provide more detailed and accurate national estimates of the prevalence of sedentary and physical activity behavior than more traditional self-report surveillance systems. In this study, the authors determined the reliability and validity of time use surveys for assessing sedentary and physical activity behavior. In 2006 and 2007, participants (n = 134) were recruited from work sites in the Australian state of New South Wales. Participants completed a 2-day time use diary twice, 7 days apart, and wore an accelerometer. The 2 diaries were compared for test-retest reliability, and comparison with the accelerometer determined concurrent validity. Participants with similar activity patterns during the 2 diary periods showed reliability intraclass correlations of 0.74 and 0.73 for nonoccupational sedentary behavior and moderate/vigorous physical activity, respectively. Comparison of the diary with the accelerometer showed Spearman correlations of 0.57-0.59 and 0.45-0.69 for nonoccupational sedentary behavior and moderate/vigorous physical activity, respectively. Time use surveys appear to be more valid for population surveillance of nonoccupational sedentary behavior and health-enhancing physical activity than more traditional surveillance systems. National time use surveys could be used to retrospectively study nonoccupational sedentary and physical activity behavior over the past 5 decades.