864 resultados para Quadrotor. Variable reference control. Position and orientation control. UAV s


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PURPOSE: It is unclear whether sociocultural and socioeconomic factors are directly linked to type 2 diabetes risk in overweight/obese ethnic minority children and adolescents. This study examines the relationships between sociocultural orientation, household social position, and type 2 diabetes risk in overweight/obese African-American (n = 43) and Latino-American (n = 113) children and adolescents. METHODS: Sociocultural orientation was assessed using the Acculturation, Habits, and Interests Multicultural Scale for Adolescents (AHIMSA) questionnaire. Household social position was calculated using the Hollingshead Two-Factor Index of Social Position. Insulin sensitivity (SI), acute insulin response (AIRG) and disposition index (DI) were derived from a frequently sampled intravenous glucose tolerance test (FSIGT). The relationships between AHIMSA subscales (i.e., integration, assimilation, separation, and marginalization), household social position and FSIGT parameters were assessed using multiple linear regression. RESULTS: For African-Americans, integration (integrating their family's culture with those of mainstream white-American culture) was positively associated with AIRG (β = 0.27 ± 0.09, r = 0.48, P < 0.01) and DI (β = 0.28 ± 0.09, r = 0.55, P < 0.01). For Latino-Americans, household social position was inversely associated with AIRG (β = -0.010 ± 0.004, r = -0.19, P = 0.02) and DI (β = -20.44 ± 7.50, r = -0.27, P < 0.01). CONCLUSIONS: Sociocultural orientation and household social position play distinct and opposing roles in shaping type 2 diabetes risk in African-American and Latino-American children and adolescents.

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The MHD wave instability in commercial cells for electrolytic aluminium production is often described using ‘shallow water’ models. The model [1] is extended for a variable height cathode bottom and anode top to account for realistic cell features. The variable depth of the two fluid layers affects the horizontal current density, the wave development and the stability threshold. Instructive examples for the 500 kA cell are presented.

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Introduction: Evidence from studies conducted mainly in the US and mainland Europe suggests that characteristics of the workforce, such as nurse patient ratios and workload (measured in a number of different ways) may be linked to variations in patient outcomes across health care settings (Carmel and Rowan 2001). Few studies have tested this relationship in the UK thus questions remain about whether we are justified in extrapolating evidence from studies conducted in very different health care systems. Objectives: To investigate whether characteristics of the nursing workforce affect patient mortality UK Intensive Care Units. Data: Patient data came from the case mix programme, Intensive Care National Audit and Research Centre (ICNARC), while information about the units came from a survey of all ICUs in England (Audit Comission 1998). The merged data set contained information on 43,859 patients in 69 units across England. ICNARC also supplied a risk adjustment variable to control for patient characteristics that are often the most important determinants of survival. Methods: Multivariate multilevel logistic regression. Findings: Higher numbers of direct care nurses and lower scores on measures of workload(proportion of occupied beds at the time the patient was admitted and mean daily transfers into the unit) were associated with lower mortality rates. Furthermore, the effect of the number of direct care nurses was greatest on the life chances of the patients who were most at risk of dying. Implications: This study has wide implications for workforce policy and planning because it shows that the size of the nursing workforce is associated with mortality (West et al 2006). Few studies have demonstrated this relationship in the UK. This study has a number of strengths and weaknesses and further research is required to determine whether this relationship between the nursing workforce and patient outcomes is causal.

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We establish a mapping between a continuous-variable (CV) quantum system and a discrete quantum system of arbitrary dimension. This opens up the general possibility to perform any quantum information task with a CV system as if it were a discrete system. The Einstein-Podolsky-Rosen state is mapped onto the maximally entangled state in any finite-dimensional Hilbert space and thus can be considered as a universal resource of entanglement. An explicit example of the map and a proposal for its experimental realization are discussed.

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The 2-year survival rate after conventional radiotherapy for carcinoma of the oesophagus is around 10–20% [8]. Concomitant chemoradiation schedules have produced survival figures of 25–30% at 5 years, and this is now considered standard treatment [1]. Conformal radiotherapy techniques offer the potential to deliver higher doses of radiation to oesophageal tumours [5], and this may improve local tumour control. However, concerns regarding late normal tissue damage to the lung parenchyma and spinal cord remain a concern. Intensitymodulated radiotherapy (IMRT) allows complex dose distributions to be produced, and can reduce the dose to radiosensitive organs close to the tumour [2]. The present study was designed to investigate the impact of beam intensity modulation on treatment planning for carcinoma of the oesophagus, by comparing a standard three-dimensional conformal radiotherapy (3DCRT) technique to an IMRT technique using the same number and orientation of treatment fields.

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En este artículo analizamos la valoración de los titulados universitarios sobre la formación recibida y su utilidad en la ocupación actual. El objetivo es analizar si existen diferencias por el nivel formativo de origen y el sexo de los estudiantes. A su vez, examinamos si las características de la situación laboral intervienen en estas relaciones afectando diferencialmente según las características sociodemográficas. Los resultados muestran la existencia de diferencias valorativas entre los jóvenes según su origen social y sexo, siendo las mujeres y los jóvenes de clase trabajadora los que valoran mejor su formación recibida. Finalmente, con la introducción de la situación laboral como variable de control constatamos que, en algunos casos, estas diferencias valorativas son debidas al contexto laboral actual de los graduadoss que a diferencias sociodemográficas.

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This paper proposes a novel image denoising technique based on the normal inverse Gaussian (NIG) density model using an extended non-negative sparse coding (NNSC) algorithm proposed by us. This algorithm can converge to feature basis vectors, which behave in the locality and orientation in spatial and frequency domain. Here, we demonstrate that the NIG density provides a very good fitness to the non-negative sparse data. In the denoising process, by exploiting a NIG-based maximum a posteriori estimator (MAP) of an image corrupted by additive Gaussian noise, the noise can be reduced successfully. This shrinkage technique, also referred to as the NNSC shrinkage technique, is self-adaptive to the statistical properties of image data. This denoising method is evaluated by values of the normalized signal to noise rate (SNR). Experimental results show that the NNSC shrinkage approach is indeed efficient and effective in denoising. Otherwise, we also compare the effectiveness of the NNSC shrinkage method with methods of standard sparse coding shrinkage, wavelet-based shrinkage and the Wiener filter. The simulation results show that our method outperforms the three kinds of denoising approaches mentioned above.

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Surface-enhanced Raman (SERS) spectra of deoxyadenosine and 5'-dAMP on Ag and Au surfaces showed the protonation of both compounds in the N1 position, their orientation geometry on metal surfaces, and the formation of Ag+ complexes at alkaline pH on hydroxylamine-reduced Ag colloids. Interestingly, substitution at the N9 position caused dramatic changes in the relative band intensities within the spectra of both deoxyadenosine and 5'-dAMP compared to that of simple adenine, although they continued to be dominated by adenine vibrations. Concentration-dependent spectra of 5'-dAMP were observed, which matched that of adenine at high concentrations and that of deoxyadenosine at lower concentration (

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It is very common to analyse the factors associated with the onset and continuation of civil wars entirely separately, as if there were likely to be no similarity between them. This is an overstatement of the theoretical position, which has established only that they may be different (i.e. less than perfectly correlated). The hypothesis that the explanatory variables are the same is not theoretically excludable and is empirically testable, both for individual variables and for combinations of them. Starting from this approach yields a rather different picture of the factors associated with the continuation of civil wars, because the relatively small sample size means that confidence intervals on individual coefficients are wide in this case. It is shown here that country size, mountainous terrain and (in most datasets) ethnic diversity seem significant for the continuation of civil wars, starting from the null hypothesis that variables affect onset and continuation probabilities identically, rather than entirely independently. One variable that affects onset and continuation significantly differently is anocracy, which we find to matter only for onset. Civil war is more likely if it occurred two years previously, as well as one year previously, which indicates that wars are more likely to restart after only one year of peace, and also more likely to stop in their first year. The combined model strengthens the result that ethnic diversity matters (it is consistently significant across datasets, whereas it is not when onset is analysed separately), although in the UCD/PRIO dataset it is significant only for onset. By contrast, if continuation is analysed independently, virtually nothing is significant except a pre-1991 dummy and a dummy for civil war two years previously.

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Fibre distribution and orientation in a series of round panel specimens of ultra high performance fibre reinforced concrete (UHPFRC) was investigated using electrical resistivity measurements and confirmed by X-ray CT imaging. By pouring specimens in different ways, the orientation of steel fibres was influenced and the sensitivity of the electrical resistivity technique was investigated. The round panels were tested in flexure and the results are discussed in relation to the observed orientation of fibres in the panels. It was found that the fibres tended to align perpendicular to the direction of flow. As a result, panels poured from the centre were significantly stronger than panels poured by other methods because the alignment of fibres led to more fibres bridging the radial cracks formed during mechanical testing.

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We report the static & dynamic magnetic characteristics of a high-layer-number NiFe/FeMn multilayer test structure with potential applications in broadband absorber and filter devices. To allow fine control over the absorption linewidths and to understand the mechanisms governing the resonances in a tailored structure similar to that expected to be used in real world applications, the multilayer was intentionally designed to have layer thickness and interface roughness variations. Magnetometry measurements show the sample has complex hysteresis loops with features consistent with single ferromagnetic film reversals. Structural characterisation by transmission electron microscopy allows us to correlate the magnetic properties with structural features. Analysis of resonance frequencies from broadband ferromagnetic resonance measurements as a function of field magnitude and orientation provide values of the local exchange bias, rotatable anisotropy, and uniaxial anisotropy fields for specific layers in the stack and explain the observed mode softening. The linewidths of the multilayer are adjustable around the bias field, approaching twice that seen at larger fields, allowing control over the bandwidth of devices formed from the structure.

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A obesidade infantil é um importante problema de saúde pública, não só pelos efeitos adversos durante a infância mas porque tende a persistir na idade adulta, constituindo um factor de risco para diversas doenças crónicas. Os alicerces de uma vida saudável estruturam-se na vida pré-natal e sedimentam-se nos seis primeiros anos de vida, sendo o crescimento da criança fortemente influenciado pelo seu contexto ambiental familiar. Foi neste âmbito que emergiu como objectivo geral deste estudo explorar as relações existentes entre os determinantes infantis (antecedentes obstétricos e peri-natais) e parentais (práticas alimentares, conhecimento dos pais sobre alimentação infantil, percepção parental de competência e percepção do peso da criança) e o desenvolvimento de excesso de peso em crianças pré-escolares. Este estudo, de carácter observacional e transversal, foi realizado com 792 crianças pré-escolares, idade M= 4,39 anos (±0,91Dp) e seus pais, residentes num concelho pertencente às NUTs III Dão-Lafões, sendo efectuada a avaliação antropométrica e classificação nutricional das crianças com base no referencial NCHS (CDC, 2000) e da OMS nos pais. O protocolo de pesquisa incluiu instrumentos de medida que validamos para a população portuguesa e a construção do Questionário de Conhecimentos sobre Alimentação Infantil (QAI) cujas propriedades psicométricas certificam a sua qualidade (Alfa de Cronbach = 0,942; Alfa de Cronbach teste re-teste = 0,977). Nas crianças, 31,3% apresentavam excesso de peso (12,4% obesidade), assim como 41,1% das mães (10,2% obesidade) e 64,4% dos pais (14,8% obesidade), sendo mais evidente nas mães o risco metabólico associado ao Perímetro da Cintura. As mães revelam mais conhecimentos sobre alimentação e sentimentos de eficácia mais elevados com o papel parental, enquanto os pais manifestaram mais sentimentos de motivação e satisfação. Os resultados obtidos corroboram existir efeito significativo dos determinantes infantis e parentais no excesso de peso da criança, designadamente: (i) do peso ao nascer, com impacto dos nascidos grandes; (ii) da higiene do sono especificamente dos que dormem menos de 11horas; (iii) dos que não brincam na rua, (iv) das mães mais jovens, do IMC e risco metabólico dos Pais; (v) da percepção parental da imagem corporal dos filhos, verificando-se que quanto mais elevado o IMC das crianças, mais distorcida é esta percepção dos pais; (vi) das crenças, atitudes e práticas alimentares e que permitem inferir que uma maior preocupação com o peso da criança, maior controlo, restrição e menor pressão para comer se associa a maior excesso de peso. As inferências evidenciam que, na vigilância de saúde periódica se torna imprescindível a valorização dos determinantes de risco biológicos e familiares do excesso de peso infantil, considerando programas de intervenção centrados na família, num processo que encontre sentido a partir daquilo que as famílias experienciam, de forma a ajudá-las a criar recursos fortalecedores de competência para uma parentalidade mais positiva.

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The South Carolina Budget and Control Board, Office of Research and Statistics annually published Statistical Abstracts, a comprehensive, single-source reference of demographic and economic data pertinent to the state. This publication is now an online publication by the South Carolina Revenue and Fiscal Affairs Office.

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The South Carolina Budget and Control Board, Office of Research and Statistics annually published Statistical Abstracts, a comprehensive, single-source reference of demographic and economic data pertinent to the state. This publication is now an online publication by the South Carolina Revenue and Fiscal Affairs Office.

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The South Carolina Budget and Control Board, Office of Research and Statistics annually published Statistical Abstracts, a comprehensive, single-source reference of demographic and economic data pertinent to the state. This publication is now an online publication by the South Carolina Revenue and Fiscal Affairs Office.