1000 resultados para 32-306


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The diffuse and regular reflectances of five optically absorbing coatings frequently used in optical systems, were measured over the 0.32-14.3 mu m wavelength range, before and after exposure to heat and intense optical radiation. The measured coatings included Nextel Velvet Black, an anodised coating and NPL Super Black. The anodised coating exhibited substantial variations in its diffuse and regular reflectance values after thermal and simulated solar ageing. Solar and thermal ageing of the Nextel Velvet Black resulted in increases of its reflectance. However, thermal ageing tended to decrease the reflectance of the other paint samples examined. Thermal and solar ageing of the NPL Super Black resulted in only minor changes in its reflectance characteristics. All measurements are traceable to the UK National Standards.

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Quadrature Phase Shift Keying (QPSK) and Dual Carrier Modulation (DCM) are currently used as the modulation schemes for Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) in the ECMA-368 defined Ultra-Wideband (UWB) radio platform. ECMA-368 has been chosen as the physical radio platform for many systems including Wireless USB (W-USB), Bluetooth 3.0 and Wireless HDMI; hence ECMA-368 is an important issue to consumer electronics and the users’ experience of these products. To enable the transport of high-rate USB, ECMA-368 offers up to 480 Mb/s instantaneous bit rate to the Medium Access Control (MAC) layer, but depending on radio channel conditions dropped packets unfortunately result in a lower throughput. This paper presents improvement on a high data rate modulation scheme that fits within the configuration of the current standard increasing system throughput by achieving 600 Mb/s (reliable to 3.2 meters) thus maintaining the high rate USB throughput even with a moderate level of dropped packets. The modulation system is termed improved and optimal Dual Circular 32-QAM (DC 32-QAM). The system performance for improved and optimal DC 32-QAM modulation is presented and compared with previous DC 32- QAM, 16-QAM and DCM.

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Quadrature Phase Shift Keying (QPSK) and Dual Carrier Modulation (DCM) are currently used as the modulation schemes for Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) in the ECMA-368 defined Ultra-Wideband (UWB) radio platform. ECMA-368 has been chosen as the physical radio platform for many systems including Wireless USB (W-USB), Bluetooth 3.0 and Wireless HDMI; hence ECMA-368 is an important issue to consumer electronics and the users experience of these products. To enable the transport of high-rate USB, ECMA-368 offers up to 480 Mb/s instantaneous bit rate to the Medium Access Control (MAC) layer, but depending on radio channel conditions dropped packets unfortunately result in a lower throughput. This paper presents an alternative high data rate modulation scheme that fits within the configuration of the current standard increasing system throughput by achieving 600 Mb/s (reliable to 3.1 meters) thus maintaining the high rate USB throughput even with a moderate level of dropped packets. The modulation system is termed Dual Circular 32-QAM (DC 32-QAM). The system performance for DC 32-QAM modulation is presented and compared with 16-QAM and DCM1.

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Life-history traits vary substantially across species, and have been demonstrated to affect substitution rates. We compute genomewide, branch-specific estimates of male mutation bias (the ratio of male-to-female mutation rates) across 32 mammalian genomes and study how these vary with life-history traits (generation time, metabolic rate, and sperm competition). We also investigate the influence of life-history traits on substitution rates at unconstrained sites across a wide phylogenetic range. We observe that increased generation time is the strongest predictor of variation in both substitution rates (for which it is a negative predictor) and male mutation bias (for which it is a positive predictor). Although less significant, we also observe that estimates of metabolic rate, reflecting replication-independent DNA damage and repair mechanisms, correlate negatively with autosomal substitution rates, and positively with male mutation bias. Finally, in contrast to expectations, we find no significant correlation between sperm competition and either autosomal substitution rates or male mutation bias. Our results support the important but frequently opposite effects of some, but not all, life history traits on substitution rates. KEY WORDS: Generation time, genome evolution, metabolic rate, sperm competition.

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Milk is the largest source of iodine in UK diets and an earlier study showed that organic summer milk had significantly lower iodine concentration than conventional milk. There are no comparable studies with winter milk or the effect of milk fat class or heat processing method. Two retail studies with winter milk are reported. Study 1 showed no effect of fat class but organic milk was 32.2% lower in iodine than conventional milk (404 vs. 595 μg/L; P < 0.001). Study 2 found no difference between conventional and Channel Island milk but organic milk contained 35.5% less iodine than conventional milk (474 vs. 306 μg/L; P < 0.001). UHT and branded organic milk also had lower iodine concentrations than conventional milk (331 μg/L; P < 0.001 and 268 μg/L: P < 0.0001 respectively). The results indicate that replacement of conventional milk by organic or UHT milk will increase the risk of sub-optimal iodine status especially for pregnant/lactating women.

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Historians have neglected tbe impact of female enfranchisement on Australian electoral outcomes. This papers employs multivariate analysis to explore electoral behaviour in New South Wales during the Great Depression. It argues that women were less prone to support Labor than men, but that women in paid employment constituted a partial exception to this pattern. In 1932 the conservative parties significantly eroded Labor's working-class support. Part of this success was due to the ability of employers to coerce workers with the threat of dismissal. Female wage earners were particularly vulnerable to this coercion. Conservative electoral appeals recast masculinity in terms of family responsibility rather than class assertion. Conflict in the household economy possibly influenced women to vote against Labor due to its identification with the cause of male breadwinners. Overall female voting behaviour was more stable than that of men and this despite the higb profile of issues that would have been expected particularly to influence female voters.

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In 1931 and 1932, New South Wales faced civic collapse. During the last months of the Lang government, the semi-fascist New Guard became a serious threat to the state. This article examines the challenge posed by the New Guard to the New South Wales police, and the strategies used by the police to suppress the group. Superintendent W.J. MacKay, the colourful and Machiavellian future commissioner, effectively and ruthlessly exercised police power against the New Guard. This article disputes the dominant historical interpretation of this period, which sees the police as collaborators with a reactionary secret army, the ‘Old Guard’.

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The purpose of the study was to investigate the relative importance of child and adolescent social and academic pathways to well-being in adulthood (32-years) indicated by a sense of meaning, social engagement, positive coping and prosocial values. Data were drawn from a 15 wave (32-year) longitudinal study of the health and development of around 1000 New Zealanders (Dunedin Multidisciplinary Health and Development Study, New Zealand). Moderate continuity in social connectedness (0.38) and high continuity in academic ability (0.90) was observed across childhood and adolescence. Adolescent social connectedness was a better predictor of adult well-being than academic achievement (0.62 vs. 0.12). There was evidence of an indirect pathway from adolescent academic achievement to adult well-being through social connectedness (0.29). Indicators of well-being in adulthood appear to be better explained by social connection rather than academic competencies pathways. Implications for promoting longer term well-being during the school years are discussed.

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BACKGROUND: The purpose of this study is to ascertain whether acute burn management (ABM) is available at health facilities in low- and middle-income countries (LMICs). METHOD: The study used the World Health Organization situational analysis tool (SAT) which is designed to assess emergency and essential surgical care and includes data points relevant to the acute management of burns. The SAT was available for 1413 health facilities in 59 countries. RESULTS: A majority (1036, 77.5 %) of the health facilities are able to perform ABM. The main reasons for the referral of ABM are lack of skills (53.4 %) and non-functioning equipment (52.2 %). Considering health centres and district/rural/community hospitals that referred due to lack of supplies/drugs and/or non-functioning equipment, almost half of the facilities were not able to provide continuous and consistent access to the equipment required either for resuscitation or to perform burn wound debridement. Out of the facilities that performed ABM, 379 (36.6 %) are capable of carrying out skin grafts and contracture release, which is indicative of their ability to manage full thickness burns. However the magnitude of full thickness burns managed was limited in half of these facilities, as they did not have access to a blood bank. CONCLUSION: The initial management of acute burns is generally available in LMICs, however it is constrained by the inability to perform resuscitation (19 %) and/or burn wound debridement (10 %). For more severe burns, an inability to perform skin grafting or contracture release limits definitive management of full thickness burns, whilst lack of availability to blood further compromises the treatment of major burns.