993 resultados para Gerard, Rudy


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There is evidence across several species for genetic control of phenotypic variation of complex traits1, 2, 3, 4, such that the variance among phenotypes is genotype dependent. Understanding genetic control of variability is important in evolutionary biology, agricultural selection programmes and human medicine, yet for complex traits, no individual genetic variants associated with variance, as opposed to the mean, have been identified. Here we perform a meta-analysis of genome-wide association studies of phenotypic variation using ~170,000 samples on height and body mass index (BMI) in human populations. We report evidence that the single nucleotide polymorphism (SNP) rs7202116 at the FTO gene locus, which is known to be associated with obesity (as measured by mean BMI for each rs7202116 genotype)5, 6, 7, is also associated with phenotypic variability. We show that the results are not due to scale effects or other artefacts, and find no other experiment-wise significant evidence for effects on variability, either at loci other than FTO for BMI or at any locus for height. The difference in variance for BMI among individuals with opposite homozygous genotypes at the FTO locus is approximately 7%, corresponding to a difference of ~0.5 kilograms in the standard deviation of weight. Our results indicate that genetic variants can be discovered that are associated with variability, and that between-person variability in obesity can partly be explained by the genotype at the FTO locus. The results are consistent with reported FTO by environment interactions for BMI8, possibly mediated by DNA methylation9, 10. Our BMI results for other SNPs and our height results for all SNPs suggest that most genetic variants, including those that influence mean height or mean BMI, are not associated with phenotypic variance, or that their effects on variability are too small to detect even with samples sizes greater than 100,000.

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Painted apple moth Teia anartoides Walker (Lepidoptera: Lymantriidae), a native to Australia, was discovered in Auckland, New Zealand in late 1999 and eradicated by 2006. It was recognised in 2002 that biological control would be the most effective long-term control strategy if eradication was unsuccessful, and a search was initiated for potential biocontrol agents in Australia. In 2003, autumn and spring surveys were undertaken in Victoria, Tasmania and South Australia of the guild of parasitoid natural enemies of T. anartoides. Eggs, larvae and pupae were collected and held to rear out any parasitoids. In addition, localised searches were made in Queensland in late 2003 early 2004 and laboratory-reared juvenile stages of T. anartoides were released for recapture in both Victoria and Queensland. Acacia dealbata Link (Fabales: Fabaceae) was the main plant from which T. anartoides was recovered, followed by apple. Most T. anartoides samples were collected from Victoria and Tasmania. Eighteen species from 13 genera of egg, larval and pupal parasitoids were reared and included Diptera (Tachinidae) and Hymenoptera (Braconidae, Encyrtidae, Eulophidae and Ichneumonidae). Of the seven Hymenopteran genera recovered from the larval stage, the most common in Victoria and Tasmania was a previously unidentified larval parasitoid Cotesia Cameron (Hymenoptera: Braconidae) sp. Echthromorpha intricatoria (Fabricius) (Hymenoptera: Ichneumonidae) was the dominant pupal parasitoid. The survey showed that the parasitoid complex associated with T anartoides is structurally very similar to that on other pest Lymantriidae in the northern hemisphere such as gypsy moth (Lymantria dispar L.) (Lepidoptera: Lymantriidae). Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) was recorded for the first time in Australia.

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Photovoltaic (PV) panels and electric domestic water heater with storage (DWH) are widely used in households in many countries. However, DWH should be explored as an energy storage mechanism before batteries when households have excess PV energy. Through a residential case study in Queensland, Australia, this paper presents a new optimized design and control solution to reduce water heating costs by utilizing existing DWH energy storage capacity and increasing PV self-consumption for water heating. The solution is produced by evaluating the case study energy profile and numerically maximizing the use of PV for DWH. A conditional probability matrix for different solar insolation and hot water usage days is developed to test the solution. Compared to other tariffs, this solution shows cost reduction from 20.8% to 63.3% This new solution could encourage solar households move to a more economical and carbon neutral water heating method.

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Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles.

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Contains correspondence, minutes, reports, clippings, manuscripts, research materials, journal articles, photographs and publications; primarily relating to Berger's involvement with Ethiopian Jewry and his efforts to bring about their rescue through the organization he formed, the American Association for Ethiopian Jews. Also contains material from Berger's other interests- his writings, travels through the world and to Israel and Ethiopia, community affiliations, research in Black American Jews, profession as a Jewish social work executive, his commitment to Jewish causes and to Israel. There are also many personal and biographical materials from the numerous long-term friendships and associations he established.

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The spectral energy associated with the carrier and sidebands of naturally sampled carrier based PWM can be spread by randomising the carrier (switch) half-period Tc = 1/2fc. So long as the switch duty cycle each period still correctly reflects the value of the modulating fundamental waveform as sampled during that switch period, then the fundamental component will remain undistorted. Natural sampling will ensure this occurs. Carrier based PWM can be extended to (m+1) level multilevel converter waveform generation by creating m triangular carriers, each with an equal 2*pi/m phase displacement. Alternatively the carrier disposition strategy calls for m amplitude displaced triangular carriers, each of amplitude 1/m and frequency mfc. Randomising these carrier sub-periods T0> = 1/2mfc is shown to generate (m+ 1) level PWM waveforms where the first (m-1) carrier groups are cancelled, while the remaining carrier and sidebands at multiples of mfc are spectrally spread. Numerous five level simulation and experimentally gathered randomised PWM waveforms are presented, showing the effects of the variation of the degree of randomisation, modulation depth and pulse number.

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Charts of the various families related to the Lindley family: Lipschitz, Heimann, Edinger, Hochstaedter, Goldschmidt, Jakobson, Braunschweig.

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Transformation of Australian education is occurring at a rapid rate through the implementation of a number of initiatives. These initiatives include the Digital Education Revolution, the move to a National Curriculum and the implementation of a National Framework for Professional Standards for Teachers and Principals. As these initiatives are rolled out to schools across Australia, the equitable access to professional learning to support all teachers, regardless of their geographical location, is in question. A number of studies have been conducted in Australia that highlight the importance of professional learning and the difficulty faced by regional and remote teachers with regard to access (Gerard Daniels, 2007; Lysons, Cooksey, Panizzon, Parnell & Pegg 2006; Ministerial Review of Schooling, 1994, Rural and Remote Education Advisory Council, 2000; Vinson, 2002). Along with access to professional learning, has been the discussion of effective modes of delivery. Face to face professional learning, in regional and metropolitan areas, is offered in isolation, or in some cases, is complimented with virtual learning environments. The need for a more sustainable approach to professional learning is highly necessary. A mixed method research approach was utilised in order to answer the primary research question "In what ways might technology be used to support professional learning of regional and remote teachers in Western Australia?" This research paper outlines the findings from the study including the significance of travel time; impact of limited relief teachers; implications for promotion and teacher registration; professional learning communities being valued but often limited by small staff numbers; professional learning conducted in the local context being preferred; professional learning established at the teacher and school level being desirable; teachers being confident in using technology and accessing PD online if required; and social cohesiveness being valued and often limited by isolation. Further, this research has culminated in the development of a "model of rethinking connectedness" that would facilitate improving the amount and variety of professional learning available to regional and remote teachers.

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Objective Foodborne illnesses in Australia, including salmonellosis, are estimated to cost over $A1.25 billion annually. The weather has been identified as being influential on salmonellosis incidence, as cases increase during summer, however time series modelling of salmonellosis is challenging because outbreaks cause strong autocorrelation. This study assesses whether switching models is an improved method of estimating weather–salmonellosis associations. Design We analysed weather and salmonellosis in South-East Queensland between 2004 and 2013 using 2 common regression models and a switching model, each with 21-day lags for temperature and precipitation. Results The switching model best fit the data, as judged by its substantial improvement in deviance information criterion over the regression models, less autocorrelated residuals and control of seasonality. The switching model estimated a 5°C increase in mean temperature and 10 mm precipitation were associated with increases in salmonellosis cases of 45.4% (95% CrI 40.4%, 50.5%) and 24.1% (95% CrI 17.0%, 31.6%), respectively. Conclusions Switching models improve on traditional time series models in quantifying weather–salmonellosis associations. A better understanding of how temperature and precipitation influence salmonellosis may identify where interventions can be made to lower the health and economic costs of salmonellosis.

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- Introduction Malaria cases have dwindled in Bhutan with aim of malaria elimination by 2016. The aims of this study are to determine the trends and burden of malaria, the costs of intensified control activities, the main donors of the control activities and the costs of different preventive measures in the pre-elimination phase (2006-2014). - Methods A descriptive analysis of malaria surveillance data from 2006-2014 was carried out, using data from the Vector-borne Disease Control Programme (VDCP), Bhutan. Malaria morbidity and mortality among local Bhutanese and foreign nationals were analysed. The cost of different control and preventive measures, and estimation of the average numbers of long-lasting insecticidal nests (LLINs) per person were calculated. - Findings There were 5,491 confirmed malaria cases from 2006 to 2014. By 2013, there was an average of one LLIN for every 1·51 individuals. The Global Fund was the main international donor accounting for > 80% of the total funds. The cost of procuring LLINs accounted for > 90% of the total cost of prevention measures. - Interpretation The malaria burden reduced significantly over the study period with high coverage of LLINs in Bhutan. This foreseeable challenges that require national attention to maintain malaria-free status after elimination are importation of malaria, particularly from India; continued protection of the population in endemic districts through complete coverage with LLINs and IRS; and exploration of local funding modalities post elimination in the event there is a reduction in international funding.

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The integration of stochastic wind power has accentuated a challenge for power system stability assessment. Since the power system is a time-variant system under wind generation fluctuations, pure time-domain simulations are difficult to provide real-time stability assessment. As a result, the worst-case scenario is simulated to give a very conservative assessment of system transient stability. In this study, a probabilistic contingency analysis through a stability measure method is proposed to provide a less conservative contingency analysis which covers 5-min wind fluctuations and a successive fault. This probabilistic approach would estimate the transfer limit of a critical line for a given fault with stochastic wind generation and active control devices in a multi-machine system. This approach achieves a lower computation cost and improved accuracy using a new stability measure and polynomial interpolation, and is feasible for online contingency analysis.

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Background: Bhutan has reduced its malaria incidence significantly in the last 5 years, and is aiming for malaria elimination by 2016. To assist with the management of the Bhutanese malaria elimination programme a spatial decision support system (SDSS) was developed. The current study aims to describe SDSS development and evaluate SDSS utility and acceptability through informant interviews. Methods: The SDSS was developed based on the open-source Quantum geographical information system (QGIS) and piloted to support the distribution of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) in the two sub-districts of Samdrup Jongkhar District. It was subsequently used to support reactive case detection (RACD) in the two sub-districts of Samdrup Jongkhar and two additional sub-districts in Sarpang District. Interviews were conducted to ascertain perceptions on utility and acceptability of 11 informants using the SDSS, including programme and district managers, and field workers. Results: A total of 1502 households with a population of 7165 were enumerated in the four sub-districts, and a total of 3491 LLINs were distributed with one LLIN per 1.7 persons. A total of 279 households representing 728 residents were involved with RACD. Informants considered that the SDSS was an improvement on previous methods for organizing LLIN distribution, IRS and RACD, and could be easily integrated into routine malaria and other vector-borne disease surveillance systems. Informants identified some challenges at the programme and field level, including the need for more skilled personnel to manage the SDSS, and more training to improve the effectiveness of SDSS implementation and use of hardware. Conclusions: The SDSS was well accepted and informants expected its use to be extended to other malaria reporting districts and other vector-borne diseases. Challenges associated with efficient SDSS use included adequate skills and knowledge, access to training and support, and availability of hardware including computers and global positioning system receivers.

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This paper presents a flexible and integrated planning tool for active distribution network to maximise the benefits of having high level s of renewables, customer engagement, and new technology implementations. The tool has two main processing parts: “optimisation” and “forecast”. The “optimization” part is an automated and integrated planning framework to optimize the net present value (NPV) of investment strategy for electric distribution network augmentation over large areas and long planning horizons (e.g. 5 to 20 years) based on a modified particle swarm optimization (MPSO). The “forecast” is a flexible agent-based framework to produce load duration curves (LDCs) of load forecasts for different levels of customer engagement, energy storage controls, and electric vehicles (EVs). In addition, “forecast” connects the existing databases of utility to the proposed tool as well as outputs the load profiles and network plan in Google Earth. This integrated tool enables different divisions within a utility to analyze their programs and options in a single platform using comprehensive information.

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Regular electrical activation waves in cardiac tissue lead to the rhythmic contraction and expansion of the heart that ensures blood supply to the whole body. Irregularities in the propagation of these activation waves can result in cardiac arrhythmias, like ventricular tachycardia (VT) and ventricular fibrillation (VF), which are major causes of death in the industrialised world. Indeed there is growing consensus that spiral or scroll waves of electrical activation in cardiac tissue are associated with VT, whereas, when these waves break to yield spiral- or scroll-wave turbulence, VT develops into life-threatening VF: in the absence of medical intervention, this makes the heart incapable of pumping blood and a patient dies in roughly two-and-a-half minutes after the initiation of VF. Thus studies of spiral- and scroll-wave dynamics in cardiac tissue pose important challenges for in vivo and in vitro experimental studies and for in silico numerical studies of mathematical models for cardiac tissue. A major goal here is to develop low-amplitude defibrillation schemes for the elimination of VT and VF, especially in the presence of inhomogeneities that occur commonly in cardiac tissue. We present a detailed and systematic study of spiral- and scroll-wave turbulence and spatiotemporal chaos in four mathematical models for cardiac tissue, namely, the Panfilov, Luo-Rudy phase 1 (LRI), reduced Priebe-Beuckelmann (RPB) models, and the model of ten Tusscher, Noble, Noble, and Panfilov (TNNP). In particular, we use extensive numerical simulations to elucidate the interaction of spiral and scroll waves in these models with conduction and ionic inhomogeneities; we also examine the suppression of spiral- and scroll-wave turbulence by low-amplitude control pulses. Our central qualitative result is that, in all these models, the dynamics of such spiral waves depends very sensitively on such inhomogeneities. We also study two types of control chemes that have been suggested for the control of spiral turbulence, via low amplitude current pulses, in such mathematical models for cardiac tissue; our investigations here are designed to examine the efficacy of such control schemes in the presence of inhomogeneities. We find that a local pulsing scheme does not suppress spiral turbulence in the presence of inhomogeneities; but a scheme that uses control pulses on a spatially extended mesh is more successful in the elimination of spiral turbulence. We discuss the theoretical and experimental implications of our study that have a direct bearing on defibrillation, the control of life-threatening cardiac arrhythmias such as ventricular fibrillation.