977 resultados para U-shaped slots


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Objective : To investigate the relationship between socioeconomic status (SES) and reported perceptions of quality of life (QOL) in a cross-sectional population-based analysis of a representative sample of Australian men.

Methods : In 917 randomly recruited men aged 24–92 years, we measured QoL in the domains of physical health, psychological health, environment and social relationships, using the Australian World Health Organization Quality of Life Instrument (WHOQOL-BREF). Residential addresses were cross-referenced with Australian Bureau of Statistics 2006 census data to ascertain SES. Participants were categorised into lower, mid, or upper SES based on the Index of Relative Socioeconomic Disadvantage and Advantage (IRSAD), the Index of Economic Resources (IER), and the Index of Education and Occupation (IEO). Lifestyle and health information was self-reported.

Results : Males of lower SES reported poorer satisfaction with physical health (OR=0.6, 95%CI 0.4–0.9, p=0.02), psychological health (OR=0.4, 95%CI 0.3–.7, <0.001) and environment (OR=0.5, 95%CI 0.3–0.7, p<0.001), although not social relationships (p=0.59). The poorest QOL for each domain was observed in the lower and upper SES groups, representing an inverse U-shaped pattern of association; however, statistical significance was only observed for psychological  health (OR=0.5, 95%CI 0.4–0.7, p<0.001). These relationships were similar for IEO  and IER.

Conclusions : Men from lower and upper SES groups have lower QOL compared to their counterparts in the mid SES group.

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The movements, diving behaviour and thermal environment occupied by 4 adult female olive ridley turtles Lepidochelys olivacea in northern Australia were determined through satellite telemetry. Patterns of behaviour recorded were rather unusual compared to other sea turtles in that dives were mainly deep, largely benthic and exceptionally long (>2 h) in some cases, characteristics typical of over-wintering turtles in colder environments. One individual occupied shallow coastal foraging zones, while the others foraged far from land (probably on the seabed) in relatively deep water (>100 m). Individuals performed long dives (frequently >100 min), but from the short post-dive intervals we suggest that these dives were mainly aerobic. Maximum dive depth recorded was 200 ± 20 m (mean maximum depths ranged from 20.1 to 46.7 m across individuals; n = 17328 dives in total; depths ≥3 m were considered ‘dives’) and the maximum duration was 200 ± 20 min (mean durations ranged from 24.5 to 48.0 min across individuals). Temperature profiles indicate that turtles experienced temperatures ranging from 23 to 29°C at the surface, with the lowest temperature recorded (18.7°C) at a depth of 98 m. Only 6.9% of the dives were in water <20°C. From time-allocation at depth (TAD) scores, we demonstrated that many dives reaching the known or inferred sea bottom were U-shaped, but there was no apparent diel signal in dive depth. This suggests that many benthic dives were not associated exclusively with resting behaviour and likely had a foraging component as well. The ability to perform long benthic dives allows this species to exploit deeper benthic environments in addition to the shallow coastal areas more generally occupied by adult hard-shelled sea turtles (e.g. green and hawksbill turtles). Deep benthic dives also occur in certain marine mammals (e.g. narwhals) and sea birds (e.g. rockhopper penguins) and therefore seem to be a general foraging strategy exploited by animals that can perform long dives.

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State-owned enterprises continue to play a considerable role in many economies. In this study we empirically investigate the connections between these enterprises and inequality as mediated through political ideology. Using cross-country data on the relative size of the state-owned enterprise sector, we find strong empirical support for an inverted U-shaped relationship between its size and income inequality. We also find strong evidence that left-wing (vis-a-vis right-wing) governments are associated with a larger state-owned enterprise sector in countries with higher inequality. This result is robust to using cross-sectional vs. panel data, different identification strategies, and various controls.

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Background: Links between alcohol consumption and depression have been reported; however, associations amongst the elderly remain unclear. We aimed to investigate the relationship between alcohol consumption and self-reported depression in a population-based sample of 514 men aged 65+ (median 76.4yr, IQR 71.2-82.4). Methods: Alcohol intake over the previous 12 months was estimated from a food frequency questionnaire. Participants were classified as non-drinkers or habitual consumers of ≤2 or ≥3 standard drinks per day. Symptoms of past and 12-month depression were ascertained by self-report based on DSM-IV criteria. Using logistic regression, we estimated the association between alcohol intake and depression, adjusting for age and lifestyle factors. Results: There were 91 non-drinkers (17.7%), 249 (48.4%) consuming ≤2 drinks/day, and 174 (33.9%) consuming ≥3 drinks/day. Forty eight (9.3%) were identified as having lifetime depression and 31 (6.0%) with 12-month depression. With those consuming ≤2 drinks/day as the reference, the odds of lifetime depression were greater for non-drinkers (OR=2.50, 95% CI 1.15-5.44) and tended to be greater for those consuming ≥3 (OR=1.45 95% CI 0.70-3.00). After excluding those with past depression, the likelihood of 12-month depression tended to be greater for non-drinkers (OR=2.38 95% CI 0.89-6.38) and those consuming ≥3 drinks/day (OR=1.68 95% CI 0.70-4.07). These associations were not explained by age, mobility, smoking, BMI, SES or number of medications. Conclusions: These results suggest a U-shaped relationship between alcohol consumption and depression in this sample of elderly men.

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The relationship between mass loss rate and chemical power in flying birds is analysed with regard to water and heat balance. Two models are presented: the first model is applicable to situations where heat loads are moderate. i.e. when heat balance can be achieved by regulating non-evaporative heat loss, and evaporative water loss is minimised. The second model is applicable when heat loads are high, non-evaporative heat loss is maximised. and heat balance has to be achieved by regulating evaporative heat loss. The rates of mass loss of two Thrush Nightingales Luscinia luscinia and one Teal Anas crecca were measured at various flight speeds in a wind tunnel. Estimates of metabolic water production indicate that the Thrush Nightingales did not dehydrate during experimental flights. Probably, the Thrush Nightingales maintained heat balance without actively increasing evaporative cooling. The Teal, however, most likely had to resort to evaporative cooling, although it may not have dehydrated. Chemical power was estimated from our mass loss rate data using the minimum evaporation model for the Thrush Nightingales and the evaporative heat regulation model for the Teal. For both Thrush Nightingales and the Teal, the chemical power calculated from our mass loss rate data showed a greater change with speed (more 'U-shaped' curve) than the theoretically predicted chemical power curves based on aerodynamic theory. The minimum power speeds calculated from our data differed little from theoretical predictions but maximum range speeds were drastically different. Mass loss rate could potentially be used to estimate chemical power in flying birds under laboratory conditions where temperature and humidity are controlled. However, the assumptions made in the models and the model predictions need further testing.

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A teal (Anas crecca) and a thrush nightingale (Luscinia luscinia) were trained to fly in the Lund wind tunnel for periods of up to 3 and 16 h respectively. Both birds flew in steady flapping flight, with such regularity that their wingbeat frequencies could be determined by viewing them through a shutter stroboscope. When flying at a constant air speed, the teal's wingbeat frequency varied with the 0.364 power of the body mass and the thrush nightingale's varied with the 0.430 power. Both exponents differed from zero, but neither differed from the predicted value (0.5) at the 1 % level of significance. The teal continued to flap steadily as the tunnel tilt angle was varied from -1° (climb) to +6° (descent), while the wingbeat frequency declined progressively by about 11%. In both birds, the plot of wingbeat frequency against air speed in level flight was U-shaped, with small but statistically significant curvature. We identified the minima of these curves with the minimum power speed (Vmp) and found that the values predicted for Vmp, using previously published default values for the required variables, were only about two-thirds of the observed minimum-frequency speeds. The discrepancy could be resolved if the body drag coefficients (CDb) of both birds were near 0.08, rather than near 0.40 as previously assumed. The previously published high values for body drag coefficients were derived from wind-tunnel measurements on frozen bird bodies, from which the wings had been removed, and had long been regarded as anomalous, as values below 0.01 are given in the engineering literature for streamlined bodies. We suggest that birds of any size that have well-streamlined bodies can achieve minimum body drag coefficients of around 0.05 if the feet can be fully retracted under the flank feathers. In such birds, field observations of flight speeds may need to be reinterpreted in the light of higher estimates of Vmp. Estimates of the effective lift:drag ratio and range can also be revised upwards. Birds that have large feet or trailing legs may have higher body drag coefficients. The original estimates of around CDb=0.4 could be correct for species, such as pelicans and large herons, that also have prominent heads. We see no evidence for any progressive reduction of body drag coefficient in the Reynolds number range covered by our experiments, that is 21600-215 000 on the basis of body cross-sectional diameter.

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This study examines the relationship between age and productivity measured based on key performance indicators (KPI) amongst academic staff at Universiti Sains Malaysia (USM). Three models were used in the analysis: linear, quadratic and piece-wise spline. The linear model indicates that age is negatively related to KPI. The quadratic model shows an inverted-U shaped relationship where KPI peaks at age 41 years. The piece-wise spline model indicates academic staff reach the peak of their productivity between ages 46-50 years with another productive age interval between 36-40 years implying 10 golden years when KPI could be harvested fruitfully. There is a significant downtrend in the KPI after 50 years of age. Other factors that have significant influence on KPI are gender, academic rank and discipline. The sub-models show that the influence of age on KPI is more significant amongst academic staff in the arts compared to the science stream. Age influence on KPI is significant amongst female staff but not male staff. We conclude that assessing performance in the workplace with regard to age requires complex methodological engagement and also needs to be based on a wider lens which recognises and includes within the discussion, the intangible and social dimensions of performance.

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This paper uses the Vietnamese Households Living Standards Surveys of 2002, 2004, 2006and 2008 to examine the effects of nonfarm activity on poverty in rural Vietnam. We show that nonfarm activity helps the poor, but not the poorest, given that households need to own a minimum level of endowment to partake in nonfarm activity. We find an inverted-U shaped relationship between households’ endowment levels and the probability of participating in nonfarm activity. Also, in contrast to previous studies which largely by-passed the endogeneity of nonfarm activity, we instrument it with nonfarm networks, and find that nonfarm activity plays an important role in poverty reduction, however, this impact decreases over time.

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In this study, we report the epidemiology and risk factors for humeral fractures (proximal humerus and shaft) among men and women residing in south-eastern Australia. Incident fractures during 2006 and 2007 were identified using X-ray reports (Geelong Osteoporosis Study Fracture Grid). Risk factors were identified using data from case-control studies conducted as part of the Geelong Osteoporosis Study. Median age of fracture was lower in males than females for proximal humerus (33.0 vs 71.2 years), but not for humeral shaft (8.9 vs 8.5 years). For females, proximal humerus fractures occurred mainly in the 70-79 and 80+ years age groups, whereas humeral shaft fractures followed a U-shaped pattern. Males showed a U-shaped pattern for both proximal humerus and humeral shaft fractures. Overall age-standardised incidence rates for proximal humerus fractures in males and females were 40.6 (95 % CI 32.7, 48.5) and 73.2 (95 % CI 62.2, 84.1) per 100,000 person years, respectively. For humeral shaft fractures, the age-standardised rate was 69.3 (95 % CI 59.0, 79.6) for males and 61.5 (95 % CI 51.9, 71.0) for females. There was an increase in risk of proximal humerus fractures in men with a lower femoral neck BMD, younger age, prior fracture and higher milk consumption. In pre-menopausal women, increased height and falls were both risk factors for proximal humerus fractures. For post-menopausal women, risk factors associated with proximal humerus fractures included a lower non-milk dairy consumption and sustaining a prior fracture. Humeral shaft fractures in both sexes were sustained mainly in childhood, while proximal humerus fractures were sustained in older adulthood. The overall age-standardised rates of proximal humerus fractures were nearly twice as high in females compared to males, whereas the incidence rates of humeral shaft fractures were similar.

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In this study, we examine the nature of the relationship between ethical leadership and unethical pro-organizational behavior (UPB), defined as unethical behavior conducted by employees with the aim of benefiting their organization, and whether the strength of the relationship differs between subordinates experiencing high and low identification with supervisor. Based on three-wave survey data obtained from 239 public sector employees in China, we find that ethical leadership has an inverted u-shaped (curvilinear) relationship with UPB. As the level of ethical leadership increases from low to moderate, UPB increases; as the level of ethical leadership increases from moderate to high, UPB decreases. Further, we find that the strength of this inverted u-curve relationship differs between subordinates with high and low identification with supervisor. That is to say, the inverted u-shaped relationship between ethical leadership and UPB was stronger when subordinates experienced high levels of identification with supervisor. The theoretical and managerial implications of our findings for understanding how to manage UPB in an organizational context are discussed. © 2012 Springer Science+Business Media Dordrecht.

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This paper analyzes how differences in the composition of wealth between human and physical capital among families affect fertility choices. These in tum influence the dynamics of wealth and income inequality across generations through a tradeoffbetween quantity and quality of children. Wealth composition affects fertility because physical capital has only a wealth effect on number of children, whereas human capital increases the time cost of child-rearing in addition to the wealth effect. I construct a model combining endogenous fertility with borrowing constraints in human capital investments, in which weaIth composition is determined endogenously. The model is calibrated to the PNAD, a Brazilian household survey, and the main findings of the paper can be summarized as follows. First, the model implies that the crosssection relationship between fertility and wealth typically displays a U-shaped pattem, reflecting differences in wealth composition between poor and rich families. Also, the quantity-quality tradeoff implies a concave cross-section relationship between investments per child and wealth. Second, as the economy develops and families overcome their bOlTowing constraints, the negative effect of weaIth on fertility becomes smaller, and persistence of inequality declines accordingly. The empirical evidence presented in this paper is consistent with both implications .

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We investigate whether and how bank complexity affects performance and systemic risk. We base the analysis on a complexity measure that captures diversification and diversity, controlling for size and other bank characteristics. We find that more complex banks exhibit a higher profitability, lower risk, and higher market share. Moreover, we show an inversely U-shaped relation between bank complexity and banks’ sensitivity to systemic shocks. The evidence challenges the view that higher bank complexity is per se bad and is consistent with theoretical models that show that diversity in the banking system is critical for financial stability.

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Biotic interactions between brachiopods and spionid polychaete worms, collected around San Juan Islands (USA), were documented using observations from live-collected individuals and traces of bioerosion found in dead brachiopod shells. Specimens of Terebratalia tranversa (Sowerby), Terebratulina unguicula (Carpenter), Laqueus californianus (Koch), and Hemithiris psittacea (Gmelin) were collected from rocky and muddy substrates, from sites ranging from 14.7-93.3 m in depth. Out of 1,131 specimens, 91 shells showed traces of bioerosion represented by horizontal tubes. Tubes are U-shaped, straight or slightly curved, sometimes branched, with both tube openings communicating externally. on internal surfaces of infested shells, blisters are observed. All brachiopod species yielded tubes, except for H. psittacea. Tubes are significantly more frequent on live specimens, and occur preferentially on larger, ventral valves. This pattern suggests selectivity by the infester rather than a taphonomic bias. Given the mode of life of studied brachiopods (epifaunal, sessile, attached to the substrate, lying on dorsal valve), ventral valves of living specimens should offer the most advantageous location for suspension-feeding infesters. Frequent infestation of brachiopods by parasitic spionids is ecologically and commercially noteworthy because farmed molluscs are also commonly infested by parasitic polychaetes. In addition, brachiopod shells are among the most common marine macroscopic fossils found in the Phanerozoic fossil record. From a paleontological perspective, spionid-infested brachiopod shells may be a prime target for studying parasite-host interactions over evolutionary time scales.

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The measurement of nitrogen dioxide at the parts-perbillion level is described. The experimental arrangement consists of two optical fibers placed on opposite sides of and in contact with a liquid film (14-57 μL in volume) supported on a U-shaped wire guide and two tubular conduits (one of which constitutes the means for the delivery of the liquid), light from a green (555 nm) light-emitting diode enters the liquid film, composed of Griess-Saltzman reagent. The transmitted light is measured by a referenced photodetection arrangement. Sample gas flows past the droplet at a low flow rate (typically 0.10-0.25 L/min). The response is proportional to the sampling period and the analyte concentration. The limit of detection for this nonoptimized arrangement is estimated to be <10 ppb by volume for a 5 min sample. Some unusual characteristics are observed. The initial absorbance, when most of the analyte/reaction product is still near the surface, is higher than that when the content of the droplet is fully mixed. The signal depends on the sample flow rate in a nonmonotonic fashion, first increasing and then decreasing with increasing sampling rate; the specific chemistry involved in the collection and determination of NO2 may be responsible.

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The study on several components of intervertebral joints is essential to understand the spine's degenerative mechanisms and to assess the best method for their treatment. For such study it is necessary to know the mechanical properties of the isolated intervertebral disc (ID) mechanical properties and, it is necessary to evaluate its stresses and strains. In order to assess the ID displacements, a fine, U-shaped blade was developed, over which two extensometers connected in a Wheatstone bridge were placed. The device was then tested on porcine spine ID, where compression loads were applied and the extremities displacements of the blade coupled to the intervertebral disc were measured. Stress/strain diagram, both on the compression and on the decompression phases, evidencing the non-linear nature of such relationship. With the experiment, it was possible to obtain approximate values of the longitudinal elasticity module (E) of the disc material and of the Poisson coefficient (n ). After several tests, E results are compatible with those obtained by others studies, with very simple and low-cost device. This experiments can be used for obtained others mechanical properties of isolated ID with precision and accuracy.