Can Spectro-Temporal Complexity Explain the Autistic Pattern of Performance on Auditory Tasks?
ERIC Educational Resources Information Center
Samson, Fabienne; Mottron, Laurent; Jemel, Boutheina; Belin, Pascal; Ciocca, Valter
2006-01-01
To test the hypothesis that level of neural complexity explain the relative level of performance and brain activity in autistic individuals, available behavioural, ERP and imaging findings related to the perception of increasingly complex auditory material under various processing tasks in autism were reviewed. Tasks involving simple material…
Beulens, Joline W J; van der Schouw, Yvonne T; Moons, Karel G M; Boshuizen, Hendriek C; van der A, Daphne L; Groenwold, Rolf H H
2013-04-01
Moderate alcohol consumption is associated with a reduced type 2 diabetes risk, but the biomarkers that explain this relation are unknown. The most commonly used method to estimate the proportion explained by a biomarker is the difference method. However, influence of alcohol-biomarker interaction on its results is unclear. G-estimation method is proposed to accurately assess proportion explained, but how this method compares with the difference method is unknown. In a case-cohort study of 2498 controls and 919 incident diabetes cases, we estimated the proportion explained by different biomarkers on the relation between alcohol consumption and diabetes using the difference method and sequential G-estimation method. Using the difference method, high-density lipoprotein cholesterol explained the relation between alcohol and diabetes by 78% (95% confidence interval [CI], 41-243), whereas high-sensitivity C-reactive protein (-7.5%; -36.4 to 1.8) or blood pressure (-6.9; -26.3 to -0.6) did not explain the relation. Interaction between alcohol and liver enzymes led to bias in proportion explained with different outcomes for different levels of liver enzymes. G-estimation method showed comparable results, but proportions explained were lower. The relation between alcohol consumption and diabetes may be largely explained by increased high-density lipoprotein cholesterol but not by other biomarkers. Ignoring exposure-mediator interactions may result in bias. The difference and G-estimation methods provide similar results. Copyright © 2013 Elsevier Inc. All rights reserved.
Potential Underlying Mechanisms for Greater Weight Gain in Massaged Preterm Infants
Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria
2010-01-01
In this paper, potential underlying mechanisms for massage therapy effects on preterm infant weight gain are reviewed. Path analyses are presented suggesting that: 1) increased vagal activity was associated with 2) increased gastric motility, which, in turn, was related to 3) greater weight gain; and 4) increased IGF-1 was related to greater weight gain. The change in vagal activity during the massage explained 49% of the variance in the change in gastric activity. And, the change in vagal activity during the massage explained 62% of the variance in the change in insulin. That the change in gastric activity was not related to the change in insulin suggests two parallel pathways via which massage therapy leads to increased weight gain: 1) insulin release via the celiac branch of the vagus; and 2) increased gastric activity via the gastric branch of the vagus. PMID:21570125
Martin, Thomas E
2015-08-28
Life history theory attempts to explain why species differ in offspring number and quality, growth rate, and parental effort. I show that unappreciated interactions of these traits in response to age-related mortality risk challenge traditional perspectives and explain life history evolution in songbirds. Counter to a long-standing paradigm, tropical songbirds grow at similar overall rates to temperate species but grow wings relatively faster. These growth tactics are favored by predation risk, both in and after leaving the nest, and are facilitated by greater provisioning of individual offspring by parents. Increased provisioning of individual offspring depends on partitioning effort among fewer young because of constraints on effort from adult and nest mortality. These growth and provisioning responses to mortality risk finally explain the conundrum of small clutch sizes of tropical birds. Copyright © 2015, American Association for the Advancement of Science.
The association of trail use with weather-related factors on an urban greenway.
Burchfield, Ryan A; Fitzhugh, Eugene C; Bassett, David R
2012-02-01
To study the association between weather-related measures and objectively measured trail use across 3 seasons. Weather has been reported as a barrier to outdoor physical activity (PA), but previous studies have explained only a small amount of the variance in PA using weather-related measures. The dependent variable of this study was trail use measured as mean hourly trail counts by an infrared trail counter located on a greenway. Each trail count represents 1 person breaking the infrared beam of the trail counter. Two sources of weather-related measures were obtained by a site-specific weather station and a public domain weather source. Temperature, relative humidity, and precipitation were significantly correlated with trail counts recorded during daylight hours. More precise hourly weather-related measures explained 42% of the variance in trail counts, regardless of the weather data source with temperature alone explaining 18% of the variance in trail counts. After controlling for all seasonal and weekly factors, every 1°F increase in temperature was associated with an increase of 1.1 trail counts/hr up to 76°F, at which point trail use began to slightly decrease. Weather-related factors have a moderate association with trail use along an urban greenway.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bearden, T.E.
1975-10-08
This report presents a discussion of the postulated mechanism that leads to the materialization and dematerialization of matter and to antigravity. The mechanism also explains why an orbital electron does not radiate energy, in contradiction to classical electromagnetic theory. One of the paradoxes of special relativity is explained. A new model of a photon is advanced. The relativistic increase of mass with velocity is explained. (GRA)
Changes in materials properties explain the effects of humidity on gecko adhesion.
Puthoff, Jonathan B; Prowse, Michael S; Wilkinson, Matt; Autumn, Kellar
2010-11-01
Geckos owe their remarkable stickiness to millions of dry setae on their toes, and the mechanism of adhesion in gecko setae has been the topic of scientific scrutiny for over two centuries. Previously, we demonstrated that van der Waals forces are sufficient for strong adhesion and friction in gecko setae, and that water-based capillary adhesion is not required. However, recent studies demonstrated that adhesion increases with relative humidity (RH) and proposed that surface hydration and capillary water bridge formation is important or even necessary. In this study, we confirmed a significant effect of RH on gecko adhesion, but rejected the capillary adhesion hypothesis. While contact forces of isolated tokay gecko setal arrays increased with humidity, the increase was similar on hydrophobic and hydrophilic surfaces, inconsistent with a capillary mechanism. Contact forces increased with RH even at high shear rates, where capillary bridge formation is too slow to affect adhesion. How then can a humidity-related increase in adhesion and friction be explained? The effect of RH on the mechanical properties of setal β-keratin has escaped consideration until now. We discovered that an increase in RH softens setae and increases viscoelastic damping, which increases adhesion. Changes in setal materials properties, not capillary forces, fully explain humidity-enhanced adhesion, and van der Waals forces remain the only empirically supported mechanism of adhesion in geckos.
Samlan, Robin A.; Story, Brad H.; Bunton, Kate
2014-01-01
Purpose To determine 1) how specific vocal fold structural and vibratory features relate to breathy voice quality and 2) the relation of perceived breathiness to four acoustic correlates of breathiness. Method A computational, kinematic model of the vocal fold medial surfaces was used to specify features of vocal fold structure and vibration in a manner consistent with breathy voice. Four model parameters were altered: vocal process separation, surface bulging, vibratory nodal point, and epilaryngeal constriction. Twelve naïve listeners rated breathiness of 364 samples relative to a reference. The degree of breathiness was then compared to 1) the underlying kinematic profile and 2) four acoustic measures: cepstral peak prominence (CPP), harmonics-to-noise ratio, and two measures of spectral slope. Results Vocal process separation alone accounted for 61.4% of the variance in perceptual rating. Adding nodal point ratio and bulging to the equation increased the explained variance to 88.7%. The acoustic measure CPP accounted for 86.7% of the variance in perceived breathiness, and explained variance increased to 92.6% with the addition of one spectral slope measure. Conclusions Breathiness ratings were best explained kinematically by the degree of vocal process separation and acoustically by CPP. PMID:23785184
Jones, Mirkka M; Tuomisto, Hanna; Borcard, Daniel; Legendre, Pierre; Clark, David B; Olivas, Paulo C
2008-03-01
The degree to which variation in plant community composition (beta-diversity) is predictable from environmental variation, relative to other spatial processes, is of considerable current interest. We addressed this question in Costa Rican rain forest pteridophytes (1,045 plots, 127 species). We also tested the effect of data quality on the results, which has largely been overlooked in earlier studies. To do so, we compared two alternative spatial models [polynomial vs. principal coordinates of neighbour matrices (PCNM)] and ten alternative environmental models (all available environmental variables vs. four subsets, and including their polynomials vs. not). Of the environmental data types, soil chemistry contributed most to explaining pteridophyte community variation, followed in decreasing order of contribution by topography, soil type and forest structure. Environmentally explained variation increased moderately when polynomials of the environmental variables were included. Spatially explained variation increased substantially when the multi-scale PCNM spatial model was used instead of the traditional, broad-scale polynomial spatial model. The best model combination (PCNM spatial model and full environmental model including polynomials) explained 32% of pteridophyte community variation, after correcting for the number of sampling sites and explanatory variables. Overall evidence for environmental control of beta-diversity was strong, and the main floristic gradients detected were correlated with environmental variation at all scales encompassed by the study (c. 100-2,000 m). Depending on model choice, however, total explained variation differed more than fourfold, and the apparent relative importance of space and environment could be reversed. Therefore, we advocate a broader recognition of the impacts that data quality has on analysis results. A general understanding of the relative contributions of spatial and environmental processes to species distributions and beta-diversity requires that methodological artefacts are separated from real ecological differences.
NASA Astrophysics Data System (ADS)
Ziefle, Reiner Georg
2013-03-01
Present day gravitational physics experiences a huge success in obtaining better and better experimental results. In some cases, the observations do not fit with the present knowledge of established physics. Phenomena, like the increase of the Astronomical Unit by 7 m per century or the so-called anomalous secular increase of the eccentricity of the lunar orbit by about 9 × 10^-12 per year, which can neither be explained by Einstein's Theory of General Relativity, nor by the Newtonian Theory of Gravitation, can be explained by the New Theory of Gravitation
Adaptive prolonged postreproductive life span in killer whales.
Foster, Emma A; Franks, Daniel W; Mazzi, Sonia; Darden, Safi K; Balcomb, Ken C; Ford, John K B; Croft, Darren P
2012-09-14
Prolonged life after reproduction is difficult to explain evolutionarily unless it arises as a physiological side effect of increased longevity or it benefits related individuals (i.e., increases inclusive fitness). There is little evidence that postreproductive life spans are adaptive in nonhuman animals. By using multigenerational records for two killer whale (Orcinus orca) populations in which females can live for decades after their final parturition, we show that postreproductive mothers increase the survival of offspring, particularly their older male offspring. This finding may explain why female killer whales have evolved the longest postreproductive life span of all nonhuman animals.
Jeran, S; Steinbrecher, A; Pischon, T
2016-08-01
Activity-related energy expenditure (AEE) might be an important factor in the etiology of chronic diseases. However, measurement of free-living AEE is usually not feasible in large-scale epidemiological studies but instead has traditionally been estimated based on self-reported physical activity. Recently, accelerometry has been proposed for objective assessment of physical activity, but it is unclear to what extent this methods explains the variance in AEE. We conducted a systematic review searching MEDLINE database (until 2014) on studies that estimated AEE based on accelerometry-assessed physical activity in adults under free-living conditions (using doubly labeled water method). Extracted study characteristics were sample size, accelerometer (type (uniaxial, triaxial), metrics (for example, activity counts, steps, acceleration), recording period, body position, wear time), explained variance of AEE (R(2)) and number of additional predictors. The relation of univariate and multivariate R(2) with study characteristics was analyzed using nonparametric tests. Nineteen articles were identified. Examination of various accelerometers or subpopulations in one article was treated separately, resulting in 28 studies. Sample sizes ranged from 10 to 149. In most studies the accelerometer was triaxial, worn at the trunk, during waking hours and reported activity counts as output metric. Recording periods ranged from 5 to 15 days. The variance of AEE explained by accelerometer-assessed physical activity ranged from 4 to 80% (median crude R(2)=26%). Sample size was inversely related to the explained variance. Inclusion of 1 to 3 other predictors in addition to accelerometer output significantly increased the explained variance to a range of 12.5-86% (median total R(2)=41%). The increase did not depend on the number of added predictors. We conclude that there is large heterogeneity across studies in the explained variance of AEE when estimated based on accelerometry. Thus, data on predicted AEE based on accelerometry-assessed physical activity need to be interpreted cautiously.
Minor, M A; Ermilov, S G; Philippov, D A; Prokin, A A
2016-11-01
We investigated communities of oribatid mites in five peat bogs in the north-west of the East European plain. We aimed to determine the extent to which geographic factors (latitude, separation distance), local environment (Sphagnum moss species, ground water level, biogeochemistry) and local habitat complexity (diversity of vascular plants and bryophytes in the surrounding plant community) influence diversity and community composition of Oribatida. There was a significant north-to-south increase in Oribatida abundance. In the variance partitioning, spatial factors explained 33.1 % of variability in abundance across samples; none of the environmental factors were significant. Across all bogs, Oribatida species richness and community composition were similar in Sphagnum rubellum and Sphagnum magellanicum, but significantly different and less diverse in Sphagnum cuspidatum. Sphagnum microhabitat explained 52.2 % of variability in Oribatida species richness, whereas spatial variables explained only 8.7 %. There was no distance decay in community similarity between bogs with increased geographical distance. The environmental variables explained 34.9 % of the variance in community structure, with vascular plants diversity, bryophytes diversity, and ground water level all contributing significantly; spatial variables explained 15.1 % of the total variance. Overall, only 50 % of the Oribatida community variance was explained by the spatial structure and environmental variables. We discuss relative importance of spatial and local environmental factors, and make general inferences about the formation of fauna in Sphagnum bogs.
Chakraborty, Sudip; Fu, Rong; Massie, Steven T; Stephens, Graeme
2016-07-05
Using collocated measurements from geostationary and polar-orbital satellites over tropical continents, we provide a large-scale statistical assessment of the relative influence of aerosols and meteorological conditions on the lifetime of mesoscale convective systems (MCSs). Our results show that MCSs' lifetime increases by 3-24 h when vertical wind shear (VWS) and convective available potential energy (CAPE) are moderate to high and ambient aerosol optical depth (AOD) increases by 1 SD (1σ). However, this influence is not as strong as that of CAPE, relative humidity, and VWS, which increase MCSs' lifetime by 3-30 h, 3-27 h, and 3-30 h per 1σ of these variables and explain up to 36%, 45%, and 34%, respectively, of the variance of the MCSs' lifetime. AOD explains up to 24% of the total variance of MCSs' lifetime during the decay phase. This result is physically consistent with that of the variation of the MCSs' ice water content (IWC) with aerosols, which accounts for 35% and 27% of the total variance of the IWC in convective cores and anvil, respectively, during the decay phase. The effect of aerosols on MCSs' lifetime varies between different continents. AOD appears to explain up to 20-22% of the total variance of MCSs' lifetime over equatorial South America compared with 8% over equatorial Africa. Aerosols over the Indian Ocean can explain 20% of total variance of MCSs' lifetime over South Asia because such MCSs form and develop over the ocean. These regional differences of aerosol impacts may be linked to different meteorological conditions.
NASA Technical Reports Server (NTRS)
Williams, M.; Harris, W. L.
1984-01-01
The purpose of the analysis is to determine if inflow turbulence distortion may be a cause of experimentally observed changes in sound pressure levels when the rotor mean loading is varied. The effect of helicopter rotor mean aerodynamics on inflow turbulence is studied within the framework of the turbulence rapid distortion theory developed by Pearson (1959) and Deissler (1961). The distorted inflow turbulence is related to the resultant noise by conventional broadband noise theory. A comparison of the distortion model with experimental data shows that the theoretical model is unable to totally explain observed increases in model rotor sound pressures with increased rotor mean thrust. Comparison of full scale rotor data with the theoretical model shows that a shear-type distortion may explain decreasing sound pressure levels with increasing thrust.
2016-01-01
Objective: Obesity has been shown to increase risk of depression. Persons with obesity experience discrimination because of their body weight. Across 3 studies, we tested for the first time whether experiencing (perceived) weight-based discrimination explains why obesity is prospectively associated with increases in depressive symptoms. Method: Data from 3 studies, including the English Longitudinal Study of Ageing (2008/2009–2012/2013), the Health and Retirement Study (2006/2008–2010/2012), and Midlife in the United States (1995/1996–2004/2005), were used to examine associations between obesity, perceived weight discrimination, and depressive symptoms among 20,286 U.S. and U.K. adults. Results: Across all 3 studies, Class II and III obesity were reliably associated with increases in depressive symptoms from baseline to follow-up. Perceived weight-based discrimination predicted increases in depressive symptoms over time and mediated the prospective association between obesity and depressive symptoms in all 3 studies. Persons with Class II and III obesity were more likely to report experiencing weight-based discrimination, and this explained approximately 31% of the obesity-related increase in depressive symptoms on average across the 3 studies. Conclusion: In U.S. and U.K. samples, the prospective association between obesity (defined using body mass index) and increases in depressive symptoms in adulthood may in part be explained by perceived weight discrimination. PMID:27748611
Can spectro-temporal complexity explain the autistic pattern of performance on auditory tasks?
Samson, Fabienne; Mottron, Laurent; Jemel, Boutheina; Belin, Pascal; Ciocca, Valter
2006-01-01
To test the hypothesis that level of neural complexity explain the relative level of performance and brain activity in autistic individuals, available behavioural, ERP and imaging findings related to the perception of increasingly complex auditory material under various processing tasks in autism were reviewed. Tasks involving simple material (pure tones) and/or low-level operations (detection, labelling, chord disembedding, detection of pitch changes) show a superior level of performance and shorter ERP latencies. In contrast, tasks involving spectrally- and temporally-dynamic material and/or complex operations (evaluation, attention) are poorly performed by autistics, or generate inferior ERP activity or brain activation. Neural complexity required to perform auditory tasks may therefore explain pattern of performance and activation of autistic individuals during auditory tasks.
Kinnunen, U; Vihko, V
1991-01-01
Free time, work and background data were related to night-rest catecholamine excretion rates in a teacher group (n = 137) during an autumn term. The explained interindividual variance increased slightly towards the end of the term. Adrenaline excretion was predicted better than noradrenaline, notedly by coffee consumption, amount of physical activity, and subjective stress feelings which explained 16% of the variance in adrenaline excretion during night rest. However, the results indicated that the differences in catecholamine excretion during night rest remained mostly unpredictable.
Iceland, John
2003-08-01
After dramatic declines in poverty from 1950 to the early 1970s in the United States, progress stalled. This article examines the association between trends in poverty and income growth, economic inequality, and changes in family structure using three measures of poverty: an absolute measure, a relative measure, and a quasi-relative one. I found that income growth explains most of the trend in absolute poverty, while inequality generally plays the most significant role in explaining trends in relative poverty. Rising inequality in the 1970s and 1980s was especially important in explaining increases in poverty among Hispanics, whereas changes in family structure played a significant role for children and African Americans through 1990. Notably, changes in family structure no longer had a significant association with trends in poverty for any group in the 1990s.
Van Dyck, Delfien; De Bourdeaudhuij, Ilse; Deliens, Tom; Deforche, Benedicte
2015-04-01
When students make the transition from high school to college or university, their physical activity (PA) levels decrease strongly. Consequently, it is of crucial importance to identify the determinants of this decline in PA. The study aims were to (1) examine changes in psychosocial factors in students during the transition from high school to college/university, (2) examine if changes in psychosocial factors and residency can predict changes in PA, and (3) investigate the moderating effects of residency on the relationship between changes in psychosocial factors and changes in PA. Between March 2008 and October 2010, 291 Flemish students participated in a longitudinal study, with baseline measurements during the final year of high school and follow-up measurements at the start of second year of college/university. At both time points, participants completed a questionnaire assessing demographics, active transportation, leisure-time sports, psychosocial variables, and residency. Repeated measures MANOVA analyses and multiple moderated hierarchic regression analyses were conducted. Modeling, self-efficacy, competition-related benefits, and health-related, external and social barriers decreased, while health-related benefits and time-related barriers increased from baseline to follow-up. Decreases in modeling and time-related barriers were associated with a decrease in active transportation (adjusted R(2) = 3.2%); residency, decreases in self-efficacy, competition-related benefits, and increases in health- and time-related barriers predicted a decrease in leisure-time sports (adjusted R(2) = 29.3%). Residency only moderated two associations between psychosocial factors and changes in PA. Residency and changes in psychosocial factors were mainly important to explain the decrease in leisure-time sports. Other factors such as distance to college/university are likely more important to explain the decrease in active transportation; these are worth exploring in future studies. Because few interactions were found, similar interventions, focusing on self-efficacy, time management, and increasing perceived benefits may be effective to increase leisure-time sports in all students.
Quantifying the Relative Contribution of Factors to Household Vehicle Miles of Travel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garikapati, Venu; Singh, Abhilash C.; Astroza, Sebastian
Household vehicle miles of travel (VMT) has been exhibiting a steady growth in post-recession years in the United States and has reached record levels in 2017. With transportation accounting for 27 percent of greenhouse gas emissions, planning professionals are increasingly seeking ways to curb vehicular travel to advance sustainable, vibrant, and healthy communities. Although there is considerable understanding of the various factors that influence household vehicular travel, there is little knowledge of their relative contribution to explaining variance in household VMT. This paper presents a holistic analysis to identify the relative contribution of socio-economic and demographic characteristics, built environment attributes,more » residential self-selection effects, and social and spatial dependency effects in explaining household VMT production. The modeling framework employs a simultaneous equations model of residential location (density) choice and household VMT generation. The analysis is performed using household travel survey data from the New York metropolitan region. Model results showed insignificant spatial dependency effects, with socio-demographic variables explaining 33 percent, density (as a key measure of built environment attributes) explaining 12 percent, and self-selection effects explaining 11 percent of the total variance in the logarithm of household VMT. The remaining 44 percent remains unexplained and attributable to omitted variables and unobserved idiosyncratic factors, calling for further research in this domain to better understand the relative contribution of various drivers of household VMT.« less
Chakraborty, Sudip; Fu, Rong; Massie, Steven T.; Stephens, Graeme
2016-01-01
Using collocated measurements from geostationary and polar-orbital satellites over tropical continents, we provide a large-scale statistical assessment of the relative influence of aerosols and meteorological conditions on the lifetime of mesoscale convective systems (MCSs). Our results show that MCSs’ lifetime increases by 3–24 h when vertical wind shear (VWS) and convective available potential energy (CAPE) are moderate to high and ambient aerosol optical depth (AOD) increases by 1 SD (1σ). However, this influence is not as strong as that of CAPE, relative humidity, and VWS, which increase MCSs’ lifetime by 3–30 h, 3–27 h, and 3–30 h per 1σ of these variables and explain up to 36%, 45%, and 34%, respectively, of the variance of the MCSs’ lifetime. AOD explains up to 24% of the total variance of MCSs’ lifetime during the decay phase. This result is physically consistent with that of the variation of the MCSs’ ice water content (IWC) with aerosols, which accounts for 35% and 27% of the total variance of the IWC in convective cores and anvil, respectively, during the decay phase. The effect of aerosols on MCSs’ lifetime varies between different continents. AOD appears to explain up to 20–22% of the total variance of MCSs’ lifetime over equatorial South America compared with 8% over equatorial Africa. Aerosols over the Indian Ocean can explain 20% of total variance of MCSs’ lifetime over South Asia because such MCSs form and develop over the ocean. These regional differences of aerosol impacts may be linked to different meteorological conditions. PMID:27313203
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chakraborty, Sudip; Fu, Rong; Massie, Steven T.
Using collocated measurements from geostationary and polar-orbital satellites over tropical continents, in this paper we provide a large-scale statistical assessment of the relative influence of aerosols and meteorological conditions on the lifetime of mesoscale convective systems (MCSs). Our results show that MCSs’ lifetime increases by 3–24 h when vertical wind shear (VWS) and convective available potential energy (CAPE) are moderate to high and ambient aerosol optical depth (AOD) increases by 1 SD (1σ). However, this influence is not as strong as that of CAPE, relative humidity, and VWS, which increase MCSs’ lifetime by 3–30 h, 3–27 h, and 3–30 hmore » per 1σ of these variables and explain up to 36%, 45%, and 34%, respectively, of the variance of the MCSs’ lifetime. AOD explains up to 24% of the total variance of MCSs’ lifetime during the decay phase. This result is physically consistent with that of the variation of the MCSs’ ice water content (IWC) with aerosols, which accounts for 35% and 27% of the total variance of the IWC in convective cores and anvil, respectively, during the decay phase. The effect of aerosols on MCSs’ lifetime varies between different continents. AOD appears to explain up to 20–22% of the total variance of MCSs’ lifetime over equatorial South America compared with 8% over equatorial Africa. Aerosols over the Indian Ocean can explain 20% of total variance of MCSs’ lifetime over South Asia because such MCSs form and develop over the ocean. Finally, these regional differences of aerosol impacts may be linked to different meteorological conditions.« less
Chakraborty, Sudip; Fu, Rong; Massie, Steven T.; ...
2016-06-16
Using collocated measurements from geostationary and polar-orbital satellites over tropical continents, in this paper we provide a large-scale statistical assessment of the relative influence of aerosols and meteorological conditions on the lifetime of mesoscale convective systems (MCSs). Our results show that MCSs’ lifetime increases by 3–24 h when vertical wind shear (VWS) and convective available potential energy (CAPE) are moderate to high and ambient aerosol optical depth (AOD) increases by 1 SD (1σ). However, this influence is not as strong as that of CAPE, relative humidity, and VWS, which increase MCSs’ lifetime by 3–30 h, 3–27 h, and 3–30 hmore » per 1σ of these variables and explain up to 36%, 45%, and 34%, respectively, of the variance of the MCSs’ lifetime. AOD explains up to 24% of the total variance of MCSs’ lifetime during the decay phase. This result is physically consistent with that of the variation of the MCSs’ ice water content (IWC) with aerosols, which accounts for 35% and 27% of the total variance of the IWC in convective cores and anvil, respectively, during the decay phase. The effect of aerosols on MCSs’ lifetime varies between different continents. AOD appears to explain up to 20–22% of the total variance of MCSs’ lifetime over equatorial South America compared with 8% over equatorial Africa. Aerosols over the Indian Ocean can explain 20% of total variance of MCSs’ lifetime over South Asia because such MCSs form and develop over the ocean. Finally, these regional differences of aerosol impacts may be linked to different meteorological conditions.« less
The power of habits: unhealthy snacking behaviour is primarily predicted by habit strength.
Verhoeven, Aukje A C; Adriaanse, Marieke A; Evers, Catharine; de Ridder, Denise T D
2012-11-01
Although increasing evidence shows the importance of habits in explaining health behaviour, many studies still rely solely on predictors that emphasize the role of conscious intentions. The present study was designed to test the importance of habit strength in explaining unhealthy snacking behaviour in a large representative community sample (N= 1,103). To test our hypothesis that habits are crucial when explaining unhealthy snacking behaviour, their role was compared to the 'Power of Food', a related construct that addresses sensitivity to food cues in the environment. Moreover, the relation between Power of Food and unhealthy snacking habits was assessed. A prospective design was used to determine the impact of habits in relation to intention, Power of Food and a number of demographic variables. One month after filling out the questionnaire, including measures of habit strength and Power of Food, participants reported their unhealthy snacking behaviour by means of a 7-day snack diary. Results showed that habit strength was the most important predictor, outperforming all other variables in explaining unhealthy snack intake. The findings demonstrate that snacking habits provide a unique contribution in explaining unhealthy snacking behaviour, stressing the importance of addressing habit strength in further research and interventions concerning unhealthy snacking behaviour. ©2012 The British Psychological Society.
Age, education, and the gender gap in the sense of control.
Slagsvold, Britt; Sørensen, Annemette
2008-01-01
High sense of control is related to benefits in many aspects of life, and education is known to be strongly related to sense of control. In this article we explore why women tend to feel a lower sense of control than men, and why the sense of control tends to be lower among the elderly than among younger people. In particular we explore the role played by education in explaining age- and gender differences in sense of control. The analysis is based on data from the first wave of the Norwegian NorLAG study, with a representative sample of adults aged 40-79 in 30 municipalities. We find that education accounts for some of the age and gender differences in sense of control, but the mediating effects of education are rather modest. We find an increasing gender gap in sense of control with age, and this increasing gap is completely explained by differences in education. Gender differences in sense of control is explained completely by four factors, which are related to resources and power; physical health, education, living with a partner, and leadership experience. Age differences in sense of control are only partially explained. Education, physical health and employment status cuts the age effect on sense of control to half. The effect of education on sense of control is partly mediated through what we suggest are tangible benefits of education, namely health, employment, and leadership experience. Education also influences individuals through socialization mechanisms. We view agentive orientation as a psychological benefit of education, and measure this characteristic with Bem's (1981) sex-role scale on masculinity. Agentive orientation completely explains the remaining effect of education on sense of control.
Gosadi, Ibrahim M.
2016-01-01
Metabolic syndrome (MS) is a combination of factors that increases the risk of cardiovascular atherosclerotic diseases including diabetes, obesity, dyslipidemia, and high blood pressure. Cardiovascular diseases are one of the leading causes of death in the adult Saudi population where the increase in cardiovascular-related mortality is augmented by the rise in the prevalence of MS. Metabolic syndrome is a multi-factorial disorder influenced by interactions between genetic and environmental components. This review aims to provide a comprehensive assessment of studied environmental and genetic factors explaining the prevalence of MS in the Kingdom of Saudi Arabia. Additionally, this review aims to illustrate factors related to the population genetics of Saudi Arabia, which might explain a proportion of the prevalence of MS. PMID:26739969
The contribution of spray formulation component variables to foliar uptake of agrichemicals.
Forster, W Alison; Kimberley, Mark O
2015-09-01
The objective of the present study was to determine the contribution of the active ingredient (AI) and surfactant, and their concentrations, to the foliar uptake of agrichemicals, and to examine the physical properties that would need to be included in a model for foliar uptake. All spray formulation component variables significantly affected uptake, explaining 73% of the deviance. The deviance explained by each factor ranged from 43% (AI concentration nested within AI) to 5.6% (surfactant). The only significant interaction was between AI and surfactant, explaining 15.8% of the deviance. Overall, 90% of the deviance could be explained by the variables and their first-order interactions. Uptake increased with increasing lipophilicity of the AI at concentrations below those causing precipitation on the leaf surface. AI concentration had a far greater (negative) effect on the uptake of the lipophilic molecule epoxiconazole. The uptake of 2-deoxy-D-glucose (DOG) and 2,4-dichlorophenoxyacetic acid (2,4-D) increased with increasing hydrophile-lipophile balance (HLB) of the surfactant, the effect of HLB being far greater on the hydrophilic molecule DOG. However, the differences observed in epoxiconazole uptake owing to the surfactant were strongly positively related to the spread area of the formulation on the leaf surface. For all AIs, uptake increased in a similar manner with increasing molar surfactant concentration. © 2014 Society of Chemical Industry.
Marceau, Lisa; McKinlay, John; Shackelton, Rebecca; Link, Carol
2011-12-01
To estimate the relative contribution of patient attributes, provider characteristics and organizational features of the doctors' workplace to the diagnosis and management of diabetes. In a factorial experimental design doctors (n = 192) viewed clinically authentic vignettes of 'patients' presenting with identical signs and symptoms. Doctor subjects were primary care doctors stratified according to gender and level of experience. During an in-person interview scheduled between real patients, doctors were asked how they would diagnosis and manage the vignette 'patients' in clinical practice. This study considered the relative contribution of patient, doctor and organizational factors. Taken together patient attributes explained only 4.4% of the variability in diabetes diagnosis. Doctor factors explained only 2.0%. The vast majority of the explained variance in diabetes diagnosis was due to organizational factors (14.3%). Relative contributions combined (patient, provider, organizational factors) explained only 20% of the total variance. Attempts to reduce health care variations usually focus on the education/activation of patients, or increased training of doctors. Our findings suggest that shifting quality improvement efforts to the area which contributes most to the creation and amplification of variations (organizational influences) may produce better results in terms of reduced variations in health care associated with diabetes. © 2010 Blackwell Publishing Ltd.
Warren, Nicholas; Dussetschleger, Jeffrey; Punnett, Laura; Cherniack, Martin G
2015-03-01
In this study, we sought to explain the rapid musculoskeletal symptomatology increase in correction officers (COs). COs are exposed to levels of biomechanical and psychosocial stressors that have strong associations with musculoskeletal disorders (MSDs) in other occupations, possibly contributing to their rapid health deterioration. Baseline survey data from a longitudinal study of COs and manufacturing line workers were used to model musculoskeletal symptom prevalence and intensity in the upper (UE) and lower (LE) extremity. Outcomes were regressed on demographics and biomechanical and psychosocial exposures. COs reported significantly higher prevalence and intensity of LE symptoms compared to the industrial workers. In regression models, job tenure was a primary driver of CO musculoskeletal outcomes. In CO models, a single biomechanical exposure, head and arms in awkward positions, explained variance in both UE and LE prevalence (β of 0.338 and 0.357, respectively), and low decision latitude was associated with increased LE prevalence and intensity (β of 0.229 and 0.233, respectively). Manufacturing models were less explanatory. Examining demographic associations with exposure intensity, we found none to be significant in manufacturing, but in CO models, important psychosocial exposure levels increased with job tenure. Symptom prevalence and intensity increased more rapidly with job tenure in corrections, compared to manufacturing, and were related to both biomechanical and psychosocial exposures. Tenure-related increases in psychosocial exposure levels may help explain the CO symptom increase. Although exposure assessment improvements are proposed, findings suggest focusing on improving the psychosocial work environment to reduce MSD prevalence and intensity in corrections. © 2014, Human Factors and Ergonomics Society.
Explaining Discrepancies in Arrest Rates Between Black and White Male Juveniles
Fite, Paula J.; Wynn, Porche’; Pardini, Dustin A.
2010-01-01
The authors investigated discrepancies in arrest rates between Black and White male juveniles by examining the role of early risk factors for arrest. Two hypotheses were evaluated: (a) Disproportionate minority arrest is due to increased exposure to early risk factors, and (b) a differential sensitivity to early risk factors contributes to disproportionate minority arrest. The study included 481 Black and White boys who were followed from childhood to early adulthood. A higher incidence of early risk factors accounted for racial differences related to any juvenile arrest, as well as differences in violence- and theft-related arrests. However, increased exposure to early risk factors did not explain race differences in drug-related arrests. Minimal support was found for the hypothesis that a differential sensitivity to risk factors accounts for disproportionate rate of minority male arrests. In sum, most racial discrepancies in juvenile male arrests were accounted for by an increased exposure to childhood risk factors. Specifically, Black boys were more likely to display early conduct problems and low academic achievement and experience poor parent–child communication, peer delinquency, and neighborhood problems, which increased their risk for juvenile arrest. PMID:19803571
Home Education: The Social Motivation
ERIC Educational Resources Information Center
Beck, Christian W.
2010-01-01
Data from a Norwegian survey show correlation between a student's socially related problems at school and the parent's social motivation for home education. I argue that more time spent at school by a student could result in more socially related problems at school, which can explain an increase in social motivation for home education.
Improving prediction of conditions that modulate dengue fever risks in Yucatán, México.
NASA Astrophysics Data System (ADS)
Laureano-Rosario, A. E.; Garcia-Rejon, J. E.; Gomez-Carro, S.; Farfan-Ale, J.; Muller-Karger, F. E.
2015-12-01
Accurately predicting vector-borne diseases is essential for communities everywhere around the world. Yet this is a difficult task, even in areas where annual epidemics occur. The primary vector for dengue virus disease (DENV) is Aedes aegypti. This is a tropical-subtropical mosquito that proliferates in urban areas. Precipitation and increased temperatures are known to promote growth, reproduction and transmission of DENV. This study assesses potential health risks on coastal communities in the northwest Yucatan Peninsula, Mexico. We studied the relation between DENV incidences and environmental data. We hypothesized that environmental parameters such as rainfall, sea surface temperature (SST), air temperature, humidity, and past DENV cases are the primary drivers of DENV incidences. We collected DENV data from the National Health Information System and demographic data from the National Institute of Statistics and Geography. Precipitation and air temperature were obtained from the National Water Commission. SST was derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR) satellite sensor. In addition, incidence of DENV cases per year was calculated. Multiple regression analyses show that previous DENV cases, minimum air temperature, humidity, and precipitation are positively related to DENV cases and explain 82% of the variation, with 77% explained by previous DENV cases (cases that took place 2-weeks before the target). A second regression model without the previous DENV cases showed 30% of the variation explained by humidity and precipitation (p<0.05). Satellite-derived SST was also included to test whether the percent variation of DENV explained increased. These results imply that if these environmental variables continue to increase with time, the trend of DENV cases will also increase. This study suggests that it is possible to significantly improve DENV prevention and prediction of potential outcomes in Yucatan using remote sensing data.
Warming-related increases in soil CO2 efflux are explained by increased below-ground carbon flux
Christian P. Giardina; Creighton M. Litton; Susan E. Crow; Gregory P Asner
2014-01-01
The universally observed exponential increase in soil-surface CO2 effux (âsoil respirationâ; FS) with increasing temperature has led to speculation that global warming will accelerate soil organic carbon (SOC) decomposition, reduce SOC storage, and drive a positive feedback to future warming. However, interpreting temperatureâFS relationships,...
Trinkoff, Alison M; Le, Rong; Geiger-Brown, Jeanne; Lipscomb, Jane; Lang, Gary
2006-11-01
Nurses are at very high risk for work-related musculoskeletal injury/disorders (MSD) with low back pain/injury being the most frequently occurring MSD. Nurses are also likely to work extended schedules (long hours, on-call, mandatory overtime, working on days off). The purpose of this study was to examine the relationship of extended work schedules in nurses to MSD. Using a longitudinal, three wave survey of 2,617 registered nurses, Wave 1 work schedule data were related to neck, shoulder, and back (MSD) cases occurring in Waves 2 or 3. Schedule characteristics increasing MSD risk included 13+ hour/days, off-shifts, weekend work, work during time off (while sick, on days off, without breaks), and overtime/on-call. These increases in risk were not explained by psychological demands, but were largely explained by physical demands. Adverse schedules are significantly related to nurse MSD. Healthier schedules, less overtime, and reducing work on days off would minimize risk and recovery time. Copyright (c) 2006 Wiley-Liss, Inc.
The optics of microscope image formation.
Wolf, David E
2013-01-01
Although geometric optics gives a good understanding of how the microscope works, it fails in one critical area, which is explaining the origin of microscope resolution. To accomplish this, one must consider the microscope from the viewpoint of physical optics. This chapter describes the theory of the microscope-relating resolution to the highest spatial frequency that a microscope can collect. The chapter illustrates how Huygens' principle or construction can be used to explain the propagation of a plane wave. It is shown that this limit increases with increasing numerical aperture (NA). As a corollary to this, resolution increases with decreasing wavelength because of how NA depends on wavelength. The resolution is higher for blue light than red light. Resolution is dependent on contrast, and the higher the contrast, the higher the resolution. This last point relates to issues of signal-to-noise and dynamic range. The use of video and new digital cameras has necessitated redefining classical limits such as those of Rayleigh's criterion. Copyright © 2007 Elsevier Inc. All rights reserved.
20 CFR 229.3 - Other regulations related to this part.
Code of Federal Regulations, 2010 CFR
2010-04-01
... family relationships which may cause an annuity to be increased under this part. Part 225 explains how... annuities. Part 219 sets out what evidence is necessary to prove eligibility and the relationships described...
ERIC Educational Resources Information Center
Guillen-Royo, Monica
2008-01-01
Within material poverty contexts, consumption and subjective wellbeing are positively and strongly related. This is usually explained in terms of the increased possibilities to satisfy basic needs that additional spending provides. Other important aspects of consumption, such as its relative, symbolic and hedonic dimensions are not generally…
Circadian Misalignment Increases C-Reactive Protein and Blood Pressure in Chronic Shift Workers.
Morris, Christopher J; Purvis, Taylor E; Mistretta, Joseph; Hu, Kun; Scheer, Frank A J L
2017-04-01
Shift work is a risk factor for inflammation, hypertension, and cardiovascular disease. This increased risk cannot be fully explained by classical risk factors. Shift workers' behavioral and environmental cycles are typically misaligned relative to their endogenous circadian system. However, there is little information on the impact of acute circadian misalignment on cardiovascular disease risk in shift workers, independent of differences in work stress, food quality, and other factors that are likely to differ between night and day shifts. Thus, our objectives were to determine the independent effect of circadian misalignment on 24-h high-sensitivity C-reactive protein (hs-CRP; a marker of systemic inflammation) and blood pressure levels-cardiovascular disease risk factors-in chronic shift workers. Chronic shift workers undertook two 3-day laboratory protocols that simulated night work, comprising 12-hour inverted behavioral and environmental cycles (circadian misalignment) or simulated day work (circadian alignment), using a randomized, crossover design. Circadian misalignment increased 24-h hs-CRP by 11% ( p < 0.0001). Circadian misalignment increased 24-h systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 1.4 mmHg and 0.8 mmHg, respectively (both p ≤ 0.038). The misalignment-mediated increase in 24-h SBP was primarily explained by an increase in SBP during the wake period (+1.7 mmHg; p = 0.017), whereas the misalignment-mediated increase in 24-h DBP was primarily explained by an increase in DBP during the sleep opportunity (+1.8 mmHg; p = 0.005). Circadian misalignment per se increases hs-CRP and blood pressure in shift workers. This may help explain the increased inflammation, hypertension, and cardiovascular disease risk in shift workers.
ERIC Educational Resources Information Center
Hatzenbuehler, Mark L.; McLaughlin, Katie A.; Nolen-Hoeksema, Susan
2008-01-01
Background: Sexual minority adolescents appear to be at increased risk for internalizing disorders relative to their heterosexual peers, but there is a paucity of research explaining this elevated risk. Emotion regulation deficits are increasingly understood as important predictors of internalizing psychopathology among general samples of…
High Selection Pressure Promotes Increase in Cumulative Adaptive Culture
Vegvari, Carolin; Foley, Robert A.
2014-01-01
The evolution of cumulative adaptive culture has received widespread interest in recent years, especially the factors promoting its occurrence. Current evolutionary models suggest that an increase in population size may lead to an increase in cultural complexity via a higher rate of cultural transmission and innovation. However, relatively little attention has been paid to the role of natural selection in the evolution of cultural complexity. Here we use an agent-based simulation model to demonstrate that high selection pressure in the form of resource pressure promotes the accumulation of adaptive culture in spite of small population sizes and high innovation costs. We argue that the interaction of demography and selection is important, and that neither can be considered in isolation. We predict that an increase in cultural complexity is most likely to occur under conditions of population pressure relative to resource availability. Our model may help to explain why culture change can occur without major environmental change. We suggest that understanding the interaction between shifting selective pressures and demography is essential for explaining the evolution of cultural complexity. PMID:24489724
Time discounting and the body mass index. Evidence from the Netherlands.
Borghans, Lex; Golsteyn, Bart H H
2006-01-01
In many Western countries, the relative weight of people -- measured by the body mass index (BMI) -- has increased substantially in recent years, leading to an increasing incidence of overweight and related health problems. As with many forms of risky behavior, it is plausible that overweight is related to the individual discount rate. Increases in credit card debts, the rise in gambling and the development of a more hedonic life style, suggest that the average discount rate has increased over time. An increase in time discounting may be a contributing factor in the rise in BMI. Applying a large set of indicators for the individual discount rate from a Dutch survey, this paper analyzes whether changes in time discounting can account for differences in body mass between individuals at a given point in time and whether changes in the average individual discount rate can explain the remarkable increase in BMI experienced in recent years in the Netherlands. We find some evidence for a link between time discounting and differences in BMI between people, but this relationship depends strongly on the choice of the proxy for the discount rate. Giving our hypothesis the best chance, we analyze the development of the time discounting proxies that are most strongly related to BMI. We find no evidence for a change of these proxies over time. Our main conclusion therefore is that overweight might be related to the way people discount future health benefits, but the increase in BMI is more likely explained by shifts in other parameters that determine the intertemporal decisions regarding the trade-off of current and future health and satisfaction.
Butchart, Alexander; Engström, Karin
2002-01-01
To test whether relations between economic development, economic inequality, and child and youth homicide rates are sex- and age-specific, and whether a country's wealth modifies the impact of economic inequality on homicide rates. Outcome variables were homicide rates around 1994 in males and females in the age ranges 0-4, 5-9, 10-14, 15-19 and 20-24 years from 61 countries. Predictor variables were per capita gross domestic product (GDP), GINI coefficient, percentage change in per capita gross national product (GNP) and female economic activity as a percentage of male economic activity. Relations were analysed by ordinary least squares regression. All predictors explained significant variances in homicide rates in those aged 15-24. Associations were stronger for males than females and weak for children aged 0-9. Models that included female economic inequality and percentage change in GNP increased the effect in children aged 0-9 and the explained variance in females aged 20-24. For children aged 0-4, country clustering by income increased the explained variance for both sexes. For males aged 15-24, the association with economic inequality was strong in countries with low incomes and weak in those with high incomes. Relations between economic factors and child and youth homicide rates varied with age and sex. Interventions to target economic factors would have the strongest impact on rates of homicide in young adults and late adolescent males. In societies with high economic inequality, redistributing wealth without increasing per capita GDP would reduce homicide rates less than redistributions linked with overall economic development.
Butchart, Alexander; Engström, Karin
2002-01-01
OBJECTIVE: To test whether relations between economic development, economic inequality, and child and youth homicide rates are sex- and age-specific, and whether a country's wealth modifies the impact of economic inequality on homicide rates. METHODS: Outcome variables were homicide rates around 1994 in males and females in the age ranges 0-4, 5-9, 10-14, 15-19 and 20-24 years from 61 countries. Predictor variables were per capita gross domestic product (GDP), GINI coefficient, percentage change in per capita gross national product (GNP) and female economic activity as a percentage of male economic activity. Relations were analysed by ordinary least squares regression. FINDINGS: All predictors explained significant variances in homicide rates in those aged 15-24. Associations were stronger for males than females and weak for children aged 0-9. Models that included female economic inequality and percentage change in GNP increased the effect in children aged 0-9 and the explained variance in females aged 20-24. For children aged 0-4, country clustering by income increased the explained variance for both sexes. For males aged 15-24, the association with economic inequality was strong in countries with low incomes and weak in those with high incomes. CONCLUSION: Relations between economic factors and child and youth homicide rates varied with age and sex. Interventions to target economic factors would have the strongest impact on rates of homicide in young adults and late adolescent males. In societies with high economic inequality, redistributing wealth without increasing per capita GDP would reduce homicide rates less than redistributions linked with overall economic development. PMID:12471400
High intelligence prevents the negative impact of anxiety on working memory.
Chuderski, Adam
2015-01-01
Using a large sample and the confirmatory factor analysis, the study investigated the relationships between anxiety, working memory (WM) and (fluid) intelligence. The study showed that the negative impact of anxiety on WM functioning diminishes with increasing intelligence, and that anxiety can significantly affect WM only in people below average intelligence. This effect could not be fully explained by the sheer differences in WM capacity (WMC), suggesting the importance of higher-level cognition in coping with anxiety. Although intelligence moderated the impact of anxiety on WM, it was only weakly related to anxiety. In contrast to previous studies, anxiety explained the substantial amount of WMC variance (17.8%) in less intelligent participants, but none of the variance in more intelligent ones. These results can be explained in terms of either increased motivation of intelligent but anxious people to cope with a WM task, or their ability to compensate decrements in WM.
Jefferis, Barbara J M H; Power, Chris; Hertzman, Clyde
2002-01-01
Objectives To examine the combined effect of social class and weight at birth on cognitive trajectories during school age and the associations between birth weight and educational outcomes through to 33 years. Design Longitudinal, population based, birth cohort study. Participants 10 845 males and females born during 3-9 March 1958 with information on birth weight, social class, and cognitive tests. Main outcome measures Reading, maths, draw a man, copying designs, verbal and non-verbal ability tests at ages 7, 11, and 16, highest qualifications achieved by 33, and trajectories of maths standardised scores at 7-16 years. Results The outcome of all childhood cognitive tests and educational achievements improved significantly with increasing birth weight. Analysis of maths scores at 7 and of highest qualifications achieved by 33 showed that the relations were robust to adjustment for potential confounding factors. For each kilogram increase in birth weight, maths z score increased by 0.17 (adjusted estimate 0.15, 95% confidence interval 0.10 to 0.21) for males and 0.21 (0.20, 0.14 to 0.25) for females. Trajectories of maths z scores between 7 and 16 years diverged for different social class groups: participants from classes I and II increased their relative position on the score with increasing age, whereas classes IV and V showed a relative decline with increasing age. Birth weight explained much less of the variation in cognition than did social class (range 0.5-1.5% v 2.9-12.5%). Conclusions The postnatal environment has an overwhelming influence on cognitive function through to early adulthood, but these strong effects do not explain the weaker but independent association with birth weight. What is already known on this topicWeight at birth is associated with later cognitive developmentThis is maintained across the range of normal birth weightsWhat this study addsSocial class at birth and birth weight have independent effects on maths scores in childhood, but social class at birth explains more of the variation in the scoresThe relation between maths scores and birth weight persists across birth weights after adjustment for gestational age, parental education, and other potential confounding factorsTrajectories of maths attainment diverge, with more affluent social groups increasing their relative advantage whereas the effect of birth weight remains constant over time PMID:12169505
Obesity: modern man's fertility nemesis.
Cabler, Stephanie; Agarwal, Ashok; Flint, Margot; du Plessis, Stefan S
2010-07-01
The obesity pandemic has grown to concerning proportions in recent years, not only in the Western World, but in developing countries as well. The corresponding decrease in male fertility and fecundity may be explained in parallel to obesity, and obesity should be considered as an etiology of male fertility. Studies show that obesity contributes to infertility by reducing semen quality, changing sperm proteomes, contributing to erectile dysfunction, and inducing other physical problems related to obesity. Mechanisms for explaining the effect of obesity on male infertility include abnormal reproductive hormone levels, an increased release of adipose-derived hormones and adipokines associated with obesity, and other physical problems including sleep apnea and increased scrotal temperatures. Recently, genetic factors and markers for an obesity-related infertility have been discovered and may explain the difference between fertile obese and infertile obese men. Treatments are available for not only infertility related to obesity, but also as a treatment for the other comorbidities arising from obesity. Natural weight loss, as well as bariatric surgery are options for obese patients and have shown promising results in restoring fertility and normal hormonal profiles. Therapeutic interventions including aromatase inhibitors, exogenous testosterone replacement therapy and maintenance and regulation of adipose-derived hormones, particularly leptin, may also be able to restore fertility in obese males. Because of the relative unawareness and lack of research in this area, controlled studies should be undertaken and more focus should be given to obesity as an etiolgy of male infertility.
The Mug:. on E = mc2 and Relativity Theory in the Mass Culture
NASA Astrophysics Data System (ADS)
Okun, L. B.
2013-11-01
This note is an attempt to explain in simple words why the famous relation E = mc2 misrepresents the essence of Einstein's relativity theory. The first part of the note is addressed to high-school teachers, the rest - to those university professors of Physics who allow themselves to say that the mass of a body increases with its velocity.
Tarkiainen, Lasse; Martikainen, Pekka; Laaksonen, Mikko
2016-03-01
First, to quantify trends in the contribution of alcohol-related mortality to mortality disparity in Finland by income quintiles. Secondly, to estimate the degree to which education, social class and economic activity explain the income-mortality association in alcohol-related and other mortality in four periods within 1988-2012. Register-based longitudinal study using an 11% random sample of Finnish residents linked to socio-economic and mortality data in 1988-2012 augmented with an 80% sample of all deaths during 1988-2007. Mortality rates and discrete time survival regression models were used to assess the income-mortality association following adjustment for covariates in 6-year periods after baseline years of 1988, 1994, 2001, and 2007. Finland. Individuals aged 35-64 years at baselines. For the four study periods for men/women, the final data set comprised, respectively, 26,360/12,825, 22,561/11,423, 20,342/11,319 and 2651/1514 deaths attributable to other causes and 7517/1217, 8199/1450, 9807/2116, 1431/318 deaths attributable to alcohol-related causes. Alcohol-related deaths were analysed with household income, education, social class and economic activity as covariates. The income disparity in mortality originated increasingly from alcohol-related causes of death, in the lowest quintile the contribution increasing from 28 to 49% among men and from 11 to 28% among women between periods 1988-93 and 2007-12. Among men, socio-economic characteristics attenuated the excess mortality during each study period in the lowest income quintile by 51-62% in alcohol-related and other causes. Among women, in the lowest quintile the attenuation was 47-76% in other causes, but there was a decreasing tendency in the proportion explained by the covariates in alcohol-related mortality. The income disparity in mortality among working-age Finns originates increasingly from alcohol-related causes of death. Roughly half the excess mortality in the lowest income quintile during 2007-12 is explained by the covariates of household income, education, social class and economic activity. © 2015 Society for the Study of Addiction.
Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver
2015-01-01
The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17–88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident. PMID:26321998
Nopp, P; Zhao, T X; Brown, B H; Wang, W
1996-11-01
ECG-gated electrical impedance tomographic spectroscopy (EITS) measurements of the lungs were taken on seven normal subjects in the frequency range 9.6 kHz to 614.4 kHz. The results show that in late systole the resistivity p' relative to the R-wave (i.e. p' = 1 at the R-wave) decreases consistently within the lung. In addition there arises an increase in p' in early systole towards the periphery of the lung. Frequency behaviour of p' changes with location. At all times after the R-wave, in the centre of the lung p' is higher at higher frequency f whereas in the periphery it is lower at higher f. The principal decrease in p' can be explained by increasing pulmonary blood volume due to cardiac contraction. The early systolic increase is presumably due to venous return to the left atrium locally leading blood output from the right ventricle which is delayed by the windkessel effect. Based on a model taking extracapillary and capillary blood volume increase into account, the change in frequency behaviour of p' is explained by regional variations in extracapillary blood vessel size determining the relative contributions of extracapillary blood volume and capillary blood volume change to p' at a certain frequency.
NASA Astrophysics Data System (ADS)
Ahlgren, Joakim; Grimvall, Anders; Omstedt, Anders; Rolff, Carl; Wikner, Johan
2017-06-01
Hypoxia and oxygen deficient zones are expanding worldwide. To properly manage this deterioration of the marine environment, it is important to identify the causes of oxygen declines and the influence of anthropogenic activities. Here, we provide a study aiming to explain the declining oxygen levels in the deep waters of the Bothnian Sea over the past 20 years by investigating data from environmental monitoring programmes. The observed decline in oxygen concentrations in deep waters was found to be primarily a consequence of water temperature increase and partly caused by an increase in dissolved organic carbon (DOC) in the seawater (R2Adj. = 0.83) as well as inflow from the adjacent sea basin. As none of the tested eutrophication-related predictors were significant according to a stepwise multiple regression, a regional increase in nutrient inputs to the area is unlikely to explain a significant portion of the oxygen decline. Based on the findings of this study, preventing the development of anoxia in the deep water of the Bothnian Sea is dependent on the large-scale measures taken to reduce climate change. In addition, the reduction of the nutrient load to the Baltic Proper is required to counteract the development of hypoxic and phosphate-rich water in the Baltic Proper, which can form deep water in the Bothnian Sea. The relative importance of these sources to oxygen consumption is difficult to determine from the available data, but the results clearly demonstrate the importance of climate related factors such as temperature, DOC and inflow from adjacent basins for the oxygen status of the sea.
ERIC Educational Resources Information Center
Shono, Yusuke; Edwards, Michael C.; Ames, Susan L.; Stacy, Alan W.
2018-01-01
Indirect tests of memory associations relevant to cannabis have been shown to be useful in explaining and predicting adolescent cannabis use habits. This study sought to increase the understanding of adolescent cannabis-related associative memory and cannabis use behavior over time. A longitudinal sample of alternative high school students (N =…
ERIC Educational Resources Information Center
Schluss, Henning
2009-01-01
In the current climate of increasing alienation from religion, traditional concepts no longer suffice to explain the relation between education and religion. Thus, Religious Education needs to take on the task of reconceiving of this relation. This article looks specifically at Religious Education in Germany. The term religious literacy, which is…
Jacobson, R.; Faust, T.
2014-01-01
Hydrologic connectivity between the channel and floodplain is thought to be a dominant factor determining floodplain processes and characteristics of floodplain forests. We explored the role of hydrologic connectivity in explaining floodplain forest community composition along streams in northern Missouri, USA. Hydrologic analyses at 20 streamgages (207–5827 km2 area) document that magnitudes of 2-year return floods increase systematically with increasing drainage area whereas the average annual number and durations of floodplain-connecting events decrease. Flow durations above the active-channel shelf vary little with increasing drainage area, indicating that the active-channel shelf is in quasi-equilibrium with prevailing conditions. The downstream decrease in connectivity is associated with downstream increase in channel incision. These relations at streamflow gaging stations are consistent with regional channel disturbance patterns: channel incision increases downstream, whereas upstream reaches have either not incised or adjusted to incision by forming new equilibrium floodplains. These results provide a framework to explain landscape-scale variations in composition of floodplain forest communities in northern Missouri. Faust (2006) had tentatively explained increases of flood-dependent tree species, and decreases of species diversity, with a downstream increase in flood magnitude and duration. Because frequency and duration of floodplain-connecting events do not increase downstream, we hypothesize instead that increases in relative abundance of flood-dependent trees at larger drainage area result from increasing size of disturbance patches. Bank-overtopping floods at larger drainage area create large, open, depositional landforms that promoted the regeneration of shade-intolerant species. Higher tree species diversity in floodplains with small drainage areas is associated with non-incised floodplains that are frequently connected to their channels and therefore subject to greater effective hydrologic variability compared with downstream floodplains. Understanding the landscape-scale geomorphic and hydrologic controls on floodplain connectivity provides a basis for more effective management and restoration of floodplain forest communities.
Litter quality versus soil microbial community controls over decomposition: a quantitative analysis
Cleveland, Cory C.; Reed, Sasha C.; Keller, Adrienne B.; Nemergut, Diana R.; O'Neill, Sean P.; Ostertag, Rebecca; Vitousek, Peter M.
2014-01-01
The possible effects of soil microbial community structure on organic matter decomposition rates have been widely acknowledged, but are poorly understood. Understanding these relationships is complicated by the fact that microbial community structure and function are likely to both affect and be affected by organic matter quality and chemistry, thus it is difficult to draw mechanistic conclusions from field studies. We conducted a reciprocal soil inoculum × litter transplant laboratory incubation experiment using samples collected from a set of sites that have similar climate and plant species composition but vary significantly in bacterial community structure and litter quality. The results showed that litter quality explained the majority of variation in decomposition rates under controlled laboratory conditions: over the course of the 162-day incubation, litter quality explained nearly two-thirds (64 %) of variation in decomposition rates, and a smaller proportion (25 %) was explained by variation in the inoculum type. In addition, the relative importance of inoculum type on soil respiration increased over the course of the experiment, and was significantly higher in microcosms with lower litter quality relative to those with higher quality litter. We also used molecular phylogenetics to examine the relationships between bacterial community composition and soil respiration in samples through time. Pyrosequencing revealed that bacterial community composition explained 32 % of the variation in respiration rates. However, equal portions (i.e., 16 %) of the variation in bacterial community composition were explained by inoculum type and litter quality, reflecting the importance of both the meta-community and the environment in bacterial assembly. Taken together, these results indicate that the effects of changing microbial community composition on decomposition are likely to be smaller than the potential effects of climate change and/or litter quality changes in response to increasing atmospheric CO2 concentrations or atmospheric nutrient deposition.
Magargal, Kate E; Parker, Ashley K; Vernon, Kenneth Blake; Rath, Will; Codding, Brian F
2017-07-08
The expansion of Numic speaking populations into the Great Basin required individuals to adapt to a relatively unproductive landscape. Researchers have proposed numerous social and subsistence strategies to explain how and why these settlers were able to replace any established populations, including private property and intensive plant processing. Here we evaluate these hypotheses and propose a new strategy involving the use of landscape fire to increase resource encounter rates. Implementing a novel, spatially explicit, multi-scalar prey choice model, we examine how individual decisions approximating each alternative strategy (private property, anthropogenic fire, and intensive plant processing) would aggregate at the patch and band level to confer an overall benefit to this colonizing population. Analysis relies on experimental data reporting resource profitability and abundance, ecological data on the historic distribution of vegetation patches, and ethnohistoric data on the distribution of Numic bands. Model results show that while resource privatization and landscape fires produce a substantial advantage, intensified plant processing garners the greatest benefit. The relative benefits of alternative strategies vary significantly across ecological patches resulting in variation across ethnographic band ranges. Combined, a Numic strategy including all three alternatives would substantially increase subsistence yields. The application of a strategy set that includes landscape fire, privatization and intensified processing of seeds and nuts, explains why the Numa were able to outcompete local populations. This approach provides a framework to help explain how individual decisions can result in such population replacement events throughout human history. © 2017 Wiley Periodicals, Inc.
Does personality affect health-related quality of life? A systematic review
Huang, I-Chan; Lee, Joy L.; Ketheeswaran, Pavinarmatha; Jones, Conor M.; Revicki, Dennis A.; Wu, Albert W.
2017-01-01
Background Health-related quality of life (HRQOL) is increasingly measured as an outcome for clinical and health services research. However, relatively little is known about how non-health factors affect HRQOL. Personality is a potentially important factor, yet evidence regarding the effects of personality on HRQOL measures is unclear. Methods This systematic review examined the relationships among aspects of personality and HRQOL. Eligible studies were identified from Medline and PsycINFO. The review included 76 English-language studies with HRQOL as a primary outcome and that assessed personality from the psychological perspective. Individuals with various health states, including ill (e.g., cancer, cardiovascular disorders), aging, and healthy, were included in this review study. Results Some personality characteristics were consistently related to psychosocial aspects more often than physical aspects of HRQOL. Personality characteristics, especially neuroticism, mastery, optimism, and sense of coherence were most likely to be associated with psychosocial HRQOL. Personality explained varying proportions of variance in different domains of HRQOL. The range of variance explained in psychosocial HRQOL was 0 to 45% and the range of explained variance in physical HRQOL was 0 to 39%. Conclusions Personality characteristics are related to HRQOL. Systematic collection and analysis of personality data alongside HRQOL measures may be helpful in medical research, clinical practice, and health policy evaluation. PMID:28355244
Tanentzap, Andrew J; Lee, William G
2017-01-01
Abiotic filters have been found either to increase or reduce evolutionary relatedness in plant communities, making it difficult to generalize responses of this major feature of biodiversity to future environmental change. Here, we hypothesized that the responses of phylogenetic structure to environmental change ultimately depend on how species have evolved traits for tolerating the resulting abiotic changes. Working within ephemeral wetlands, we tested whether species were increasingly related as flooding duration intensified. We also identified the mechanisms underlying increased relatedness by measuring root aerenchyma volume (RAV), a trait which promotes waterlogging tolerance. We found that species-specific responses to flooding explained most of the variation in occurrence for 63 vascular plant species across 5170 plots. For a subset of 22 species, we attributed these responses to variation in RAV. Large RAV specifically increased occurrence when flooding lasted for longer time periods, because large RAV reduced above-ground biomass loss. As large RAV was evolutionarily conserved within obligate wetland species, communities were more phylogenetically related as flooding increased. Our study shows how reconstructing the evolutionary history of traits that influence the responses of species to environmental change can help to predict future patterns in phylogenetic structure. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
NASA Astrophysics Data System (ADS)
Green, Fergus
2018-06-01
Until recently, national bans on fossil fuel-related activities were a taboo subject, but they are now becoming increasingly common. The logic of appropriateness that underpins such bans is key to understanding their normative appeal, and to explaining and predicting their proliferation.
Vernon, Lynette; Modecki, Kathryn L; Barber, Bonnie L
2017-01-01
Concerns are growing about adolescents' problematic social networking and possible links to depressed mood and externalizing behavior. Yet there remains little understanding of underlying processes that may account for these associations, including the mediating role of sleep disruption. This study tests this putative mediating process and examines change in problematic social networking investment and disrupted sleep, in relation to change in depressed mood and externalizing behavior. A sample of 874 students (41% male; 57.2% Caucasian; baseline M age = 14.4 years) from 27 high schools were surveyed. Participants' problematic social networking, sleep disruption, and psychopathology (depressed mood, externalizing behaviors) were measured annually over 3 years. Longitudinal mediation was tested using latent trajectories of problematic social networking use, sleep disruption, and psychopathology. Both problematic social networking and sleep disruption underwent positive linear growth over time. Adolescents who increasingly invested in social networking reported increased depressed mood, with around 53% of this association explained by the indirect effect of increased sleep disruptions. Further, adolescents who increasingly invested in social networking also reported increased externalizing behavior; some of this relation was explained (13%) via increased sleep disruptions. However an alternative model in which increased externalizing was associated with increased social networking, mediated by sleep disruptions, indicated a reciprocal relation of similar magnitude. It is important for parents, teachers, and psychologists to minimize the negative effects of social networking on adolescents' psychopathology. Interventions should potentially target promoting healthy sleep habits through reductions in social networking investment and rescheduling usage away from bedtime.
Phosphorus and nitrogen fluxes carried by 21 Finnish agricultural rivers in 1985-2006.
Ekholm, Petri; Rankinen, Katri; Rita, Hannu; Räike, Antti; Sjöblom, Heidi; Raateland, Arjen; Vesikko, Ljudmila; Cano Bernal, José Enrique; Taskinen, Antti
2015-04-01
The Finnish Agri-Environmental Programme aims to reduce nutrient load to waters. Using national monitoring data, we estimated the agricultural load (incl. natural background) of total phosphorus (TP) and total nitrogen (TN) transported by 21 Finnish rivers to the northern Baltic Sea and analysed the flow-adjusted trends in the loads and concentrations from 1985 to 2006. We also related the loads to spatial and temporal patterns in catchment and agricultural characteristics. Agricultural load of TN increased, especially in the rivers discharging into the Bothnian Bay, while the load of TP decreased in most of the rivers, except those discharging into the Archipelago Sea. The trends may partly be related to a decrease in grassed area (TP, TN) and increased mineralisation (TN), but the available data on catchment and agricultural characteristics did not fully explain the observed pattern. Our study showed that data arising from relatively infrequent monitoring may prove useful for analysing long-term trend. The mutual correlation among the explaining variables hampered the analysis of the load generating factors.
On the challenges of drawing conclusions from p-values just below 0.05
2015-01-01
In recent years, researchers have attempted to provide an indication of the prevalence of inflated Type 1 error rates by analyzing the distribution of p-values in the published literature. De Winter & Dodou (2015) analyzed the distribution (and its change over time) of a large number of p-values automatically extracted from abstracts in the scientific literature. They concluded there is a ‘surge of p-values between 0.041–0.049 in recent decades’ which ‘suggests (but does not prove) questionable research practices have increased over the past 25 years.’ I show the changes in the ratio of fractions of p-values between 0.041–0.049 over the years are better explained by assuming the average power has decreased over time. Furthermore, I propose that their observation that p-values just below 0.05 increase more strongly than p-values above 0.05 can be explained by an increase in publication bias (or the file drawer effect) over the years (cf. Fanelli, 2012; Pautasso, 2010, which has led to a relative decrease of ‘marginally significant’ p-values in abstracts in the literature (instead of an increase in p-values just below 0.05). I explain why researchers analyzing large numbers of p-values need to relate their assumptions to a model of p-value distributions that takes into account the average power of the performed studies, the ratio of true positives to false positives in the literature, the effects of publication bias, and the Type 1 error rate (and possible mechanisms through which it has inflated). Finally, I discuss why publication bias and underpowered studies might be a bigger problem for science than inflated Type 1 error rates, and explain the challenges when attempting to draw conclusions about inflated Type 1 error rates from a large heterogeneous set of p-values. PMID:26246976
Whiteman, Noah Kerness; Matson, Kevin D; Bollmer, Jennifer L; Parker, Patricia G
2005-01-01
An increased susceptibility to disease is one hypothesis explaining how inbreeding hastens extinction in island endemics and threatened species. Experimental studies show that disease resistance declines as inbreeding increases, but data from in situ wildlife systems are scarce. Genetic diversity increases with island size across the entire range of an extremely inbred Galápagos endemic bird, providing the context for a natural experiment examining the effects of inbreeding on disease susceptibility. Extremely inbred populations of Galápagos hawks had higher parasite abundances than relatively outbred populations. We found a significant island effect on constitutively produced natural antibody (NAb) levels and inbred populations generally harboured lower average and less variable NAb levels than relatively outbred populations. Furthermore, NAb levels explained abundance of amblyceran lice, which encounter the host immune system. This is the first study linking inbreeding, innate immunity and parasite load in an endemic, in situ wildlife population and provides a clear framework for assessment of disease risk in a Galápagos endemic. PMID:16618672
Baxter, Suzanne Domel; Royer, Julie A.; Hitchcock, David B.
2013-01-01
BACKGROUND A positive relationship exists between children’s body mass index (BMI) and energy intake at school-provided meals. To help explain this relationship, we investigated 7 outcome variables concerning aspects of school-provided meals—energy content of items selected, number of meal components selected, number of meal components eaten, amounts eaten of standardized school-meal portions, energy intake from flavored milk, energy intake received in trades, and energy content given in trades. METHODS We observed children in grade 4 (N=465) eating school-provided breakfast and lunch on one to 4 days per child. We measured children’s weight and height. For daily values at school meals, a generalized linear model was fit with BMI (dependent variable) and the 7 outcome variables, sex, and age (independent variables). RESULTS BMI was positively related to amounts eaten of standardized school-meal portions (p < .0001) and increased 8.45 kg/m2 per serving, controlling for other variables in the model. BMI was positively related to energy intake from flavored milk (p = .0041) and increased 0.347 kg/m2 for every 100-kcal consumed. BMI was negatively related to energy intake received in trades (p = .0003) and decreased 0.468 kg/m2 for every 100-kcal received. BMI was not significantly related to 4 outcome variables. CONCLUSIONS Knowing that relationships between BMI and actual consumption, not selection, at school-provided meals explained the (previously found) positive relationship between BMI and energy intake at school-provided meals is helpful for school-based obesity interventions. PMID:23517000
Lagattuta, Kristin Hansen
2005-01-01
This research investigated 4- through 7-year-olds' and adults' (n = 64) concepts about the emotional consequences of desire fulfillment versus desire inhibition in situations where people's desires conflict with prohibitive rules. Results revealed developmental increases in attributing positive or mixed emotions to story characters that make willpower decisions and negative or mixed emotions to characters that transgress. These developmental changes in emotion predictions were accompanied by age-related differences in emotion explanations. Whereas 4- and 5-year-olds largely explained emotions in relation to the characters' goals, 7-year-olds and adults further explained how rules and future consequences influence emotions. Results are discussed in relation to connections among children's psychological, deontic, and future-oriented reasoning about emotions as well as the development of self-control.
Neuroimaging explanations of age-related differences in task performance.
Steffener, Jason; Barulli, Daniel; Habeck, Christian; Stern, Yaakov
2014-01-01
Advancing age affects both cognitive performance and functional brain activity and interpretation of these effects has led to a variety of conceptual research models without always explicitly linking the two effects. However, to best understand the multifaceted effects of advancing age, age differences in functional brain activity need to be explicitly tied to the cognitive task performance. This work hypothesized that age-related differences in task performance are partially explained by age-related differences in functional brain activity and formally tested these causal relationships. Functional MRI data was from groups of young and old adults engaged in an executive task-switching experiment. Analyses were voxel-wise testing of moderated-mediation and simple mediation statistical path models to determine whether age group, brain activity and their interaction explained task performance in regions demonstrating an effect of age group. Results identified brain regions whose age-related differences in functional brain activity significantly explained age-related differences in task performance. In all identified locations, significant moderated-mediation relationships resulted from increasing brain activity predicting worse (slower) task performance in older but not younger adults. Findings suggest that advancing age links task performance to the level of brain activity. The overall message of this work is that in order to understand the role of functional brain activity on cognitive performance, analysis methods should respect theoretical relationships. Namely, that age affects brain activity and brain activity is related to task performance.
Mechanisms of mindfulness training: Monitor and Acceptance Theory (MAT).
Lindsay, Emily K; Creswell, J David
2017-02-01
Despite evidence linking trait mindfulness and mindfulness training with a broad range of effects, still little is known about its underlying active mechanisms. Mindfulness is commonly defined as (1) the ongoing monitoring of present-moment experience (2) with an orientation of acceptance. Building on conceptual, clinical, and empirical work, we describe a testable theoretical account to help explain mindfulness effects on cognition, affect, stress, and health outcomes. Specifically, Monitor and Acceptance Theory (MAT) posits that (1), by enhancing awareness of one's experiences, the skill of attention monitoring explains how mindfulness improves cognitive functioning outcomes, yet this same skill can increase affective reactivity. Second (2), by modifying one's relation to monitored experience, acceptance is necessary for reducing affective reactivity, such that attention monitoring and acceptance skills together explain how mindfulness improves negative affectivity, stress, and stress-related health outcomes. We discuss how MAT contributes to mindfulness science, suggest plausible alternatives to the account, and offer specific predictions for future research. Copyright © 2016 Elsevier Ltd. All rights reserved.
Mechanisms of Mindfulness Training: Monitor and Acceptance Theory (MAT)1
Lindsay, Emily K.; Creswell, J. David
2016-01-01
Despite evidence linking trait mindfulness and mindfulness training with a broad range of effects, still little is known about its underlying active mechanisms. Mindfulness is commonly defined as (1) the ongoing monitoring of present-moment experience (2) with an orientation of acceptance. Building on conceptual, clinical, and empirical work, we describe a testable theoretical account to help explain mindfulness effects on cognition, affect, stress, and health outcomes. Specifically, Monitor and Acceptance Theory (MAT) posits that (1), by enhancing awareness of one’s experiences, the skill of attention monitoring explains how mindfulness improves cognitive functioning outcomes, yet this same skill can increase affective reactivity. Second (2), by modifying one’s relation to monitored experience, acceptance is necessary for reducing affective reactivity, such that attention monitoring and acceptance skills together explain how mindfulness improves negative affectivity, stress, and stress-related health outcomes. We discuss how MAT contributes to mindfulness science, suggest plausible alternatives to the account, and offer specific predictions for future research. PMID:27835764
Large enhancement in photocurrent by Mn doping in CdSe/ZTO quantum dot sensitized solar cells.
Pimachev, Artem; Poudyal, Uma; Proshchenko, Vitaly; Wang, Wenyong; Dahnovsky, Yuri
2016-09-29
We find a large enhancement in the efficiency of CdSe quantum dot sensitized solar cells by doping with manganese. In the presence of Mn impurities in relatively small concentrations (2.3%) the photoelectric current increases by up to 190%. The average photocurrent enhancement is about 160%. This effect cannot be explained by a light absorption mechanism because the experimental and theoretical absorption spectra demonstrate that there is no change in the absorption coefficient in the presence of the Mn impurities. To explain such a large increase in the injection current we propose a tunneling mechanism of electron injection from the quantum dot LUMO state to the Zn 2 SnO 4 (ZTO) semiconductor photoanode. The calculated enhancement is approximately equal to 150% which is very close to the experimental average value of 160%. The relative discrepancy between the calculated and experimentally measured ratios of the IPCE currents is only 6.25%. For other mechanisms (such as electron trapping, etc.) the remaining 6.25% cannot explain the large change in the experimental IPCE. Thus we have indirectly proved that electron tunneling is the major mechanism of photocurrent enhancement. This work proposes a new approach for a significant improvement in the efficiency of quantum dot sensitized solar cells.
Polarization in Raman spectroscopy helps explain bone brittleness in genetic mouse models
NASA Astrophysics Data System (ADS)
Makowski, Alexander J.; Pence, Isaac J.; Uppuganti, Sasidhar; Zein-Sabatto, Ahbid; Huszagh, Meredith C.; Mahadevan-Jansen, Anita; Nyman, Jeffry S.
2014-11-01
Raman spectroscopy (RS) has been extensively used to characterize bone composition. However, the link between bone biomechanics and RS measures is not well established. Here, we leveraged the sensitivity of RS polarization to organization, thereby assessing whether RS can explain differences in bone toughness in genetic mouse models for which traditional RS peak ratios are not informative. In the selected mutant mice-activating transcription factor 4 (ATF4) or matrix metalloproteinase 9 (MMP9) knock-outs-toughness is reduced but differences in bone strength do not exist between knock-out and corresponding wild-type controls. To incorporate differences in the RS of bone occurring at peak shoulders, a multivariate approach was used. Full spectrum principal components analysis of two paired, orthogonal bone orientations (relative to laser polarization) improved genotype classification and correlation to bone toughness when compared to traditional peak ratios. When applied to femurs from wild-type mice at 8 and 20 weeks of age, the principal components of orthogonal bone orientations improved age classification but not the explanation of the maturation-related increase in strength. Overall, increasing polarization information by collecting spectra from two bone orientations improves the ability of multivariate RS to explain variance in bone toughness, likely due to polarization sensitivity to organizational changes in both mineral and collagen.
Bravo, Adrian J; Pearson, Matthew R; Henson, James M
2017-01-02
Understanding the potential psychosocial mechanisms that explain (i.e., mediate) the associations between depressive symptoms and alcohol-related problems can improve interventions targeting college students. The current research examined four distinct facets of rumination (e.g., problem-focused thoughts, counterfactual thinking, repetitive thoughts, and anticipatory thoughts) and drinking to cope motives as potential explanatory mechanisms by which depressive symptoms are associated with increased alcohol-related problems. Participants were undergraduate students from a large, southeastern university in the United States that consumed at least one drink per typical week in the previous month (n = 403). The majority of participants were female (n = 291; 72.2%), identified as being either White, non-Hispanic (n = 210; 52.1%), or African American (n = 110; 27.3%), and reported a mean age of 21.92 (SD = 5.75) years. Structural equation modeling was conducted examining the concurrent associations between depressive symptoms, rumination facets, drinking to cope motives, and alcohol-related problems (i.e., cross-sectional). There was one significant double-mediated association that suggested that increased depressive symptoms is associated with increased problem-focused thoughts, which is associated with higher drinking to cope motives and alcohol-related problems. Conclusions/Importance: Our results suggests that problem-focused thoughts at least partially explains the associations between depression and maladaptive coping (i.e., drinking to cope), which in turn is related to problematic drinking among college students. Limitations and future directions are discussed.
A case-mix classification system for explaining healthcare costs using administrative data in Italy.
Corti, Maria Chiara; Avossa, Francesco; Schievano, Elena; Gallina, Pietro; Ferroni, Eliana; Alba, Natalia; Dotto, Matilde; Basso, Cristina; Netti, Silvia Tiozzo; Fedeli, Ugo; Mantoan, Domenico
2018-03-04
The Italian National Health Service (NHS) provides universal coverage to all citizens, granting primary and hospital care with a copayment system for outpatient and drug services. Financing of Local Health Trusts (LHTs) is based on a capitation system adjusted only for age, gender and area of residence. We applied a risk-adjustment system (Johns Hopkins Adjusted Clinical Groups System, ACG® System) in order to explain health care costs using routinely collected administrative data in the Veneto Region (North-eastern Italy). All residents in the Veneto Region were included in the study. The ACG system was applied to classify the regional population based on the following information sources for the year 2015: Hospital Discharges, Emergency Room visits, Chronic disease registry for copayment exemptions, ambulatory visits, medications, the Home care database, and drug prescriptions. Simple linear regressions were used to contrast an age-gender model to models incorporating more comprehensive risk measures aimed at predicting health care costs. A simple age-gender model explained only 8% of the variance of 2015 total costs. Adding diagnoses-related variables provided a 23% increase, while pharmacy based variables provided an additional 17% increase in explained variance. The adjusted R-squared of the comprehensive model was 6 times that of the simple age-gender model. ACG System provides substantial improvement in predicting health care costs when compared to simple age-gender adjustments. Aging itself is not the main determinant of the increase of health care costs, which is better explained by the accumulation of chronic conditions and the resulting multimorbidity. Copyright © 2018. Published by Elsevier B.V.
Attention-related changes in correlated neuronal activity arise from normalization mechanisms
Verhoef, Bram-Ernst; Maunsell, John H.R.
2017-01-01
Attention is believed to enhance perception by altering the correlations between pairs of neurons. How attention changes neuronal correlations is unknown. Using multi-electrodes in primate visual cortex, we measured spike-count correlations when single or multiple stimuli were presented, and stimuli were attended or unattended. When stimuli were unattended, adding a suppressive, non-preferred, stimulus beside a preferred stimulus increased spike-count correlations between pairs of similarly-tuned neurons, but decreased spike-count correlations between pairs of oppositely-tuned neurons. These changes are explained by a stochastic normalization model containing populations of oppositely-tuned, mutually-suppressive neurons. Importantly, this model also explains why attention decreased (attend preferred stimulus) or increased (attend non-preferred stimulus) correlations: as an indirect consequence of attention-related changes in the inputs to normalization mechanisms. Our findings link normalization mechanisms to correlated neuronal activity and attention, showing that normalization mechanisms shape response correlations and that these correlations change when attention biases normalization mechanisms. PMID:28553943
Regional myocardial flow heterogeneity explained with fractal networks
VAN BEEK, JOHANNES H. G. M.; ROGER, STEPHEN A.; BASSINGTHWAIGHTE, JAMES B.
2010-01-01
There is explain how the distribution of flow broadens with an increase in the spatial resolution of the measurement, we developed fractal models for vascular networks. A dichotomous branching network of vessels represents the arterial tree and connects to a similar venous network. A small difference in vessel lengths and radii between the two daughter vessels, with the same degree of asymmetry at each branch generation, predicts the dependence of the relative dispersion (mean ± SD) on spatial resolution of the perfusion measurement reasonably well. When the degree of asymmetry increases with successive branching, a better fit to data on sheep and baboons results. When the asymmetry is random, a satisfactory fit is found. These models show that a difference in flow of 20% between the daughter vessels at a branch point gives a relative dispersion of flow of ~30% when the heart is divided into 100–200 pieces. Although these simple models do not represent anatomic features accurately, they provide valuable insight on the heterogeneity of flow within the heart. PMID:2589520
The role of rehearsal and generation in false memory creation.
Marsh, Elizabeth J; Bower, Gordon H
2004-11-01
The current research investigated one possible mechanism underlying false memories in the Deese-Roediger-McDermott (DRM) paradigm. In the DRM paradigm, participants who study lists of related words (e.g., "table, sitting, bench ...") frequently report detailed memories for the centrally related but non-presented critical lure (e.g., "chair"). One possibility is that participants covertly call to mind the critical non-presented lure during the study phase, and later misattribute memory for this internally generated event to its external presentation. To investigate this, the DRM paradigm was modified to allow collection of on-line thoughts during the study phase. False recognition increased following generation during study. False recognition also increased following study of longer lists; this effect was partially explained by the fact that longer lists were more likely to elicit generations of the critical lure during study. Generation of the lure during study contributes to later false recognition, although it does not explain the entire effect.
McCartney, G; Bouttell, J; Craig, N; Craig, P; Graham, L; Lakha, F; Lewsey, J; McAdams, R; MacPherson, M; Minton, J; Parkinson, J; Robinson, M; Shipton, D; Taulbut, M; Walsh, D; Beeston, C
2016-03-01
This paper tests the extent to which differing trends in income, demographic change and the consequences of an earlier period of social, economic and political change might explain differences in the magnitude and trends in alcohol-related mortality between 1991 and 2011 in Scotland compared to England & Wales (E&W). Comparative time trend analyses and arithmetic modelling. Three approaches were utilised to compare Scotland with E&W: 1. We modelled the impact of changes in income on alcohol-related deaths between 1991-2001 and 2001-2011 by applying plausible assumptions of the effect size through an arithmetic model. 2. We used contour plots, graphical exploration of age-period-cohort interactions and calculation of Intrinsic Estimator coefficients to investigate the effect of earlier exposure to social, economic and political adversity on alcohol-related mortality. 3. We recalculated the trends in alcohol-related deaths using the white population only to make a crude approximation of the maximal impact of changes in ethnic diversity. Real incomes increased during the 1990s but declined from around 2004 in the poorest 30% of the population of Great Britain. The decline in incomes for the poorest decile, the proportion of the population in the most deprived decile, and the inequality in alcohol-related deaths, were all greater in Scotland than in E&W. The model predicted less of the observed rise in Scotland (18% of the rise in men and 29% of the rise in women) than that in E&W (where 60% and 68% of the rise in men and women respectively was explained). One-third of the decline observed in alcohol-related mortality in Scottish men between 2001 and 2011 was predicted by the model, and the model was broadly consistent with the observed trends in E&W and amongst women in Scotland. An age-period interaction in alcohol-related mortality was evident for men and women during the 1990s and 2000s who were aged 40-70 years and who experienced rapidly increasing alcohol-related mortality rates. Ethnicity is unlikely to be important in explaining the trends or differences between Scotland and E&W. The decline in alcohol-related mortality in Scotland since the early 2000s and the differing trend to E&W were partly described by a model predicting the impact of declining incomes. Lagged effects from historical social, economic and political change remain plausible from the available data. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Young Children’s Adjustment as a Function of Maltreatment, Shame, and Anger
Bennett, David S.; Sullivan, Margaret Wolan; Lewis, Michael
2007-01-01
Maltreated children are at increased risk for behavior problems. This study examines a model in which shame mediates the potential relation between maltreatment and anger, and anger mediates the potential relation between shame and behavior problems. Participants were 177 children (ages 3 to 7 years) and their mothers, 90 of whom had histories of perpetrating neglect and/or physical abuse. Physical abuse, but not neglect, was related to increased shame during an evaluative task; shame was related to increased anger; and anger to teacher ratings of total behavior problems and externalizing problems. Age moderated the relation between physical abuse and adjustment, as abuse was related to more total problems only among the younger children. Anger was a significant mediator of shame and both behavior problems and externalizing problems. Shame, anger, age, and type of maltreatment appear to be important factors in explaining variance in behavioral adjustment following a history of maltreatment. PMID:16204734
Rutstein, S. O.
2000-01-01
The 1990s have seen a remarkable decrease in mortality among infants and children in most developing countries. In some countries, particularly in sub-Saharan Africa, these declines in mortality among children have slowed and are now increasing again. Internationally comparable data derived from survey programmes, such as the Demographic and Health Survey (DHS) programme, are available both to document the changes that have occurred in mortality and to provide insight into some of the factors that may explain these trends in mortality. The factors found in repeated DHS programmes that explain these trends fall into five categories: fertility behaviour; nutritional status, breastfeeding, and infant feeding; the use of health services by mothers and for children; environmental health conditions; and socioeconomic status. Both simple analyses and multivariate analyses of changes in these factors between surveys indicate that all factors affected the mortality trends. However, to explain trends in mortality, the variables themselves had to have changed over time. During the 1990s fertility behaviour, breastfeeding, and infant feeding have changed less than other factors and so would seem to have played a smaller role in mortality trends. This study confirms that trends in mortality during the 1990s were related to more than just a handful of variables. It would, therefore, be a mistake to concentrate policy actions on one or a few of these while forsaking others. Countries with the largest decreases in mortality have had substantial improvements in most of the factors that might be used to explain these changes. In some countries mortality has risen. In part these increases can be explained by the factors included in this study, such as deterioration in seeking medical care for children with fever. Other factors that were not measured, such as the increasing resistance of malaria to drug treatment and the increased prevalence of parental HIV/AIDS, may be contributing to the increase noted. PMID:11100620
Garza, Kimberly Bosworth; Harris, Carole V; Bolding, Mark S
2013-01-01
Studies have shown a negative association between value of the future (preference for long-term vs. short-term rewards) and harmful addictive behaviors; however, research in the area of preventive behaviors is limited and has shown conflicting results. The primary objectives were: (1) to examine the association among value of the future and diet and physical activity (PA) behaviors, and (2) to assess whether value of the future explained additional variance in behaviors after controlling for theory-based health beliefs related to coronary heart disease (CHD). An online survey was conducted in adults (N = 172) with no prior history of CHD. A delay discounting task was administered to measure value of the future. Questionnaire items were based on the Health Belief Model (HBM) and included CHD knowledge, perceived risk, perceived severity, perceived benefits of and barriers to behavior change, self-efficacy, cues to action, diet and PA behaviors and demographic variables. High value of the future was associated with younger age, lower BMI, more healthful diet, and increased PA. After controlling for HBM components and demographics, value of the future did not explain any additional variance in diet or PA behaviors. Significant predictors of healthful diet included female gender (P = .013), increased age (P = .029), greater than high school education (P = .023), greater diet-related self-efficacy (P = .021), and not having received a healthcare provider recommendation to improve diet (P = .018). Significant predictors of PA level included income between $20,000 and $69,999 (P = .014), greater exercise-related self-efficacy (P < .001) and not having received a healthcare provider recommendation to increase levels of PA (P = .015). Behaviors to prevent CHD may be associated with a person's outlook on the future; however, self-efficacy was a stronger predictor of behavior. These findings support recommendations for enhancement of diet- and PA-related self-efficacy and problem-solving to address myopia in terms of long-term health benefits. Copyright © 2013 Elsevier Inc. All rights reserved.
Kim, Gwang Suk; Cho, Won Jung; Lee, Chung Yul; Marion, Lucy N; Kim, Mi Ja
2005-01-01
To identify the relationship of work stress and family stress to the health of women in Korea. Cross-sectional study. Three hundred and thirty-one married women working in 14 manufacturing companies in Korea. Subjects responded to a questionnaire that included items on work stress, family stress, social support, and general characteristics. Perceived health status (PHS) was assessed with the Short Form-36. There was a significant positive relationship between social support and PHS, but significant negative relationships were found between PHS and work stress as well as family stress. Hierarchical multiple regression analysis explained the health status of married working women by four categories: personal, work related, family related, and social support, and accounted for 45.4% of the variance. When family-related factors were added to the model, the power of explanation was increased by 17.9% compared with the explained variance. Family stress was a major variable not only for explaining the variance but also for correlating with health status. Both work stress and family stress should be considered together when addressing the health of working women in the industrial sector in Korea.
Do Lower-Body Dimensions and Body Composition Explain Vertical Jump Ability?
Caia, Johnpaul; Weiss, Lawrence W; Chiu, Loren Z F; Schilling, Brian K; Paquette, Max R; Relyea, George E
2016-11-01
Caia, J, Weiss, LW, Chiu, LZF, Schilling, BK, Paquette, MR, and Relyea, GE. Do lower-body dimensions and body composition explain vertical jump ability? J Strength Cond Res 30(11): 3073-3083, 2016-Vertical jump (VJ) capability is integral to the level of success attained by individuals participating in numerous sport and physical activities. Knowledge of factors related to jump performance may help with talent identification and/or optimizing training prescription. Although myriad variables are likely related to VJ, this study focused on determining if various lower-body dimensions and/or body composition would explain some of the variability in performance. Selected anthropometric dimensions were obtained from 50 university students (25 men and 25 women) on 2 occasions separated by 48 or 72 hours. Estimated body fat percentage (BF%), height, body weight, hip width, pelvic width, bilateral quadriceps angle (Q-angle), and bilateral longitudinal dimensions of the feet, leg, thigh, and lower limb were obtained. Additionally, participants completed countermovement VJs. Analysis showed BF% to have the highest correlation with countermovement VJ displacement (r = -0.76, p < 0.001). When examining lower-body dimensions, right-side Q-angle displayed the strongest association with countermovement VJ displacement (r = -0.58, p < 0.001). Regression analysis revealed that 2 different pairs of variables accounted for the greatest variation (66%) in VJ: (a) BF% and sex and (b) BF% and body weight. Regression models involving BF% and lower-body dimensions explained up to 61% of the variance observed in VJ. Although the variance explained by BF% may be increased by using several lower-body dimensions, either sex identification or body weight explains comparatively more. Therefore, these data suggest that the lower-body dimensions measured herein have limited utility in explaining VJ performance.
ERIC Educational Resources Information Center
Koger, Dale
2001-01-01
Explains how colleges and universities can increase revenue and enhance status by upgrading their stadiums and arenas. Related issues considered are: determining how much a school should add to its existing stadium and arena, selecting the design and management team, and raising capital. Outlines key areas that design and construction teams should…
Explaining Outsourcing in Health, Sport and Physical Education
ERIC Educational Resources Information Center
Williams, Benjamin J.; Macdonald, Doune
2015-01-01
Outsourcing is a complex, controversial and pervasive practice that is increasingly becoming a matter of concern for educational researchers. This article contributes to this literature by examining outsourcing practices related to health, sport and physical education (HSPE). Specifically, it reports data on specialist health and physical…
Guinn, Caroline H; Baxter, Suzanne D; Royer, Julie A; Hitchcock, David B
2013-05-01
A 2010 publication showed a positive relationship between children's body mass index (BMI) and energy intake at school-provided meals (as assessed by direct meal observations). To help explain that relationship, we investigated 7 outcome variables concerning aspects of school-provided meals: energy content of items selected, number of meal components selected, number of meal components eaten, amounts eaten of standardized school-meal portions, energy intake from flavored milk, energy intake received in trades, and energy content given in trades. Fourth-grade children (N = 465) from Columbia, SC, were observed eating school-provided breakfast and lunch on 1 to 4 days per child. Researchers measured children's weight and height. For daily values at school meals, a generalized linear model was fit with BMI (dependent variable) and the 7 outcome variables, sex, and age (independent variables). BMI was positively related to amounts eaten of standardized school-meal portions (p < .0001) and increased 8.45 kg/m(2) per serving, controlling for other variables in the model. BMI was positively related to energy intake from flavored milk (p = .0041) and increased 0.347 kg/m(2) for every 100 kcal consumed. BMI was negatively related to energy intake received in trades (p = .0003) and decreased 0.468 kg/m(2) for every 100 kcal received. BMI was not significantly related to 4 outcome variables. Knowing that relationships between BMI and actual consumption, not selection, at school-provided meals explained the (previously found) positive relationship between BMI and energy intake at school-provided meals is helpful for school-based obesity interventions. © 2013, American School Health Association.
Östergren, Olof
2015-08-01
Although absolute levels of mortality have decreased among Swedish men and women in recent decades, educational inequalities in mortality have increased, especially among women. The aim of this study is to disentangle the role of income and family type in educational inequalities in mortality in Sweden during 1990-2009, focusing on gender differences. Data on individuals born in Sweden between the ages of 30 and 74 years were collected from total population registries, covering a total of 529,275 deaths and 729 million person-months. Temporary life expectancies (age 30-74 years) by education were calculated using life tables, and rate ratios were estimated with Poisson regression with robust standard errors. Temporary life expectancy improved among all groups except low educated women. Relative educational inequalities in mortality (RRs) increased from 1.79 to 1.98 among men and from 1.78 to 2.10 among women. Variation in family type explained some of the inequalities among men, but not among women, and did not contribute to the trend. Variation in income explained a larger part of the educational inequalities among men compared to women and also explained the increase in educational inequalities in mortality among men and women. Increasing educational inequalities in mortality in Sweden may be attributed to the increase in income inequalities in mortality. © 2015 the Nordic Societies of Public Health.
Macronutrient Composition of Menu Offerings in Fast Food Restaurants in the U.S.
Jarlenski, Marian P; Wolfson, Julia A; Bleich, Sara N
2016-10-01
A high intake of fast food is associated with increased obesity risk. This study assessed recent changes in caloric content and macronutrient composition in large U.S. fast food restaurants. Data from the MenuStat project included 11,737 menu items in 37 fast food restaurants from 2012 to 2014. Generalized linear models were used to examine changes in the caloric content and corresponding changes in the macronutrient composition (non-sugar carbohydrates, sugar, unsaturated fat, saturated fat, and protein) of menu items over time. Additionally, macronutrient composition was compared in menu items newly introduced in 2013 and 2014, relative to 2012. Analyses, conducted in January 2016, controlled for restaurant and were stratified by menu categories. Overall, there was a 22-calorie reduction in food items from 2012 to 2014. Beverages had a 46-calorie increase, explained by an increase in calories from sugar (12 calories) and saturated fat (16 calories). Newly introduced main courses in 2014 had 59 calories fewer than those on 2012 menus, explained by a 54-calorie reduction in unsaturated fat, while other macronutrient content remained fairly constant. Newly introduced dessert items in 2014 had 90 calories more than those on 2012 menus, explained primarily by an increase of 57 calories of sugar. Overall, there were relatively minor changes in menu items' caloric and macronutrient composition. Although declines in caloric content among newly introduced fast food main courses may improve the public's caloric intake, it appears that the macronutrient composition of newly introduced items did not shift to a healthier profile. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
In Search of Graduate Employability: An Exploration of Student Identity
ERIC Educational Resources Information Center
Smith, Sally; Smith, Colin; Taylor-Smith, Ella; Fotheringham, Julia
2017-01-01
Universities are adopting institution-wide projects to increase student work placements and work-related learning across all subject disciplines. However, there are large variations between programs in uptake, with limited evidence explaining why this might be the case. This study uses identity theory (Stryker, 1980) to explore student perceptions…
Truncation Without Shape Constraints: The Latter Stages of Prosodic Acquisition.
ERIC Educational Resources Information Center
Kehoe, Margaret M.
2000-01-01
Evaluates the claim of uniform size and shape restrictions in prosodic development using a cross-sectional database of English-speaking children's multisyllabic word productions. Suggests children's increasing faithfulness to unstressed syllables can be explained by different constraint rankings that relate to edge alignment, syllable structure,…
Effective Classroom Demonstration of Soil Reinforcing Techniques.
ERIC Educational Resources Information Center
Williams, John Wharton; Fox, Dennis James
1986-01-01
Presents a model for demonstrating soil mass stabilization. Explains how this approach can assist students in understanding the various types of soil reinforcement techniques, their relative contribution to increased soil strength, and some of their limitations. A working drawing of the model and directives for construction are included. (ML)
An Empirical Exploration of Factors Related to Adolescents' Political Efficacy
ERIC Educational Resources Information Center
Levy, Brett L. M.
2013-01-01
Political scientists have found that one of the strongest predictors of political participation is political efficacy, the belief that individuals' actions can influence political processes. Prior research indicates that political efficacy increases through various experiences, such as discussions of public issues, but it does not explain why or…
Drug expenditure and new drug introductions: the Swedish experience.
Gerdtham, U G; Johannesson, M; Jönsson, B
1993-09-01
This article measures the impact of the switch to new and more expensive drugs on the aggregate drug expenditure (both prescription and nonprescription) in Sweden during the period 1974 to 1991, and also on the disaggregated expenditure for 3 medical areas: asthma, hypertension and peptic ulcer disease. During the period studied, nominal drug expenditure increased 6-fold. The retail price index of drugs and the number of prescribed drugs accounted for 51.6 and 5.8% of this increase, respectively. The remaining residual amount accounted for 42.6%. Since the price index of drugs increased more slowly than the overall net price index of goods and services, the relative price of drugs decreased dramatically by about 30%. This means that increases in prices of drugs cannot explain the increase in real inflation-adjusted drug expenditure. We also show that the residual increase can be partly explained by the introduction of new and more expensive drugs. It is therefore argued that economic evaluations which compare the extra costs induced by new drugs with the extra benefits should be undertaken to guide decisions about the prescription of new and more expensive drugs.
Effects of emotional valence and arousal on the voice perception network
Kotz, Sonja A.; Belin, Pascal
2017-01-01
Abstract Several theories conceptualise emotions along two main dimensions: valence (a continuum from negative to positive) and arousal (a continuum that varies from low to high). These dimensions are typically treated as independent in many neuroimaging experiments, yet recent behavioural findings suggest that they are actually interdependent. This result has impact on neuroimaging design, analysis and theoretical development. We were interested in determining the extent of this interdependence both behaviourally and neuroanatomically, as well as teasing apart any activation that is specific to each dimension. While we found extensive overlap in activation for each dimension in traditional emotion areas (bilateral insulae, orbitofrontal cortex, amygdalae), we also found activation specific to each dimension with characteristic relationships between modulations of these dimensions and BOLD signal change. Increases in arousal ratings were related to increased activations predominantly in voice-sensitive cortices after variance explained by valence had been removed. In contrast, emotions of extreme valence were related to increased activations in bilateral voice-sensitive cortices, hippocampi, anterior and midcingulum and medial orbito- and superior frontal regions after variance explained by arousal had been accounted for. Our results therefore do not support a complete segregation of brain structures underpinning the processing of affective dimensions. PMID:28449127
Explaining match outcome in elite Australian Rules football using team performance indicators.
Robertson, Sam; Back, Nicole; Bartlett, Jonathan D
2016-01-01
The relationships between team performance indicators and match outcome have been examined in many team sports, however are limited in Australian Rules football. Using data from the 2013 and 2014 Australian Football League (AFL) regular seasons, this study assessed the ability of commonly reported discrete team performance indicators presented in their relative form (standardised against their opposition for a given match) to explain match outcome (Win/Loss). Logistic regression and decision tree (chi-squared automatic interaction detection (CHAID)) analyses both revealed relative differences between opposing teams for "kicks" and "goal conversion" as the most influential in explaining match outcome, with two models achieving 88.3% and 89.8% classification accuracies, respectively. Models incorporating a smaller performance indicator set displayed a slightly reduced ability to explain match outcome (81.0% and 81.5% for logistic regression and CHAID, respectively). However, both were fit to 2014 data with reduced error in comparison to the full models. Despite performance similarities across the two analysis approaches, the CHAID model revealed multiple winning performance indicator profiles, thereby increasing its comparative feasibility for use in the field. Coaches and analysts may find these results useful in informing strategy and game plan development in Australian Rules football, with the development of team-specific models recommended in future.
Ekenberg, C; Lodding, I P; Wareham, N E; Sørensen, S S; Sengeløv, H; Gustafsson, F; Rasmussen, A; Perch, M; Lundgren, J D; Helleberg, M
2017-12-01
Transplant recipients are at high risk of cytomegalovirus (CMV) infection. Mechanisms explaining the variation in risk of infections are far from fully elucidated. We hypothesised that host genetics explains part of the variation in risk of infection and examined if relatives of recipients with CMV infection have higher rates of severe infections compared to relatives of recipients without this infectious phenotype. In a register-based study, we included first-degree relatives of transplant recipients and examined the risk of hospitalisation due to overall infection or viral infection and risk of death among relatives of recipients who developed CMV infection within the first year of transplantation compared to relatives of recipients without CMV. Analyses were adjusted for sex, age and calendar year. We included 4470 relatives who were followed for 103,786 person-years, median follow-up 24 years [interquartile range (IQR) 12-36]. There were a total of 1360 infection-related hospitalisations in the follow-up period, incidence rate (IR) 13.1/1000 person-years [95% confidence interval (CI), 12.4; 13.8]. 206 relatives were hospitalised with viral infection, IR 1.8/1000 person-years (95% CI, 1.6; 2.0). There was no increased risk of hospitalisation due to infections, IR ratio (IRR) 0.99 (95% CI, 0.88; 1.12), nor specifically viral infections, IRR 0.87 (95% CI, 0.63; 1.19), in relatives of recipients with CMV compared to relatives of recipients without CMV. Also, no difference was seen in analyses stratified by transplant type, family relation and CMV serostatus. The risk of hospitalisation due to infection is not increased among first-degree relatives of transplant recipients with CMV infection compared to relatives of recipients without CMV.
NASA Astrophysics Data System (ADS)
van der Wal, Daphne; Lambert, Gwladys I.; Ysebaert, Tom; Plancke, Yves M. G.; Herman, Peter M. J.
2017-10-01
Variations in abundance and diversity of estuarine benthic macrofauna are typically described along the salinity gradient. The influence of gradients in water depth, hydrodynamic energy and sediment properties are less well known. We studied how these variables influence the distribution of subtidal macrofauna in the polyhaline zone of a temperate estuary (Westerschelde, SW Netherlands). Macrofauna density, biomass and species richness, combined in a so-called ecological richness, decreased with current velocities and median grain-size and increased with organic carbon of the sediment, in total explaining 39% of the variation. The macrofauna community composition was less well explained by the three environmental variables (approx. 12-15% in total, with current velocity explaining approx. 8%). Salinity, water depth and distance to the intertidal zone had a very limited effect on both ecological richness and the macrofauna community. The proportion of (surface) deposit feeders (including opportunistic species), decreased relative to that of omnivores and carnivores with increasing current velocity and sediment grain-size. In parallel, the proportion of burrowing sessile benthic species decreased relative to that of mobile benthic species that are able to swim. Correspondingly, spatial variations in hydrodynamics yielded distinct hotspots and coldspots in ecological richness. The findings highlight the importance of local hydrodynamic conditions for estuarine restoration and conservation. The study provides a tool based on a hydrodynamic model to assess and predict ecological richness in estuaries.
A multi-scale examination of stopover habitat use by birds
Buler, J.J.; Moore, F.R.; Woltmann, S.
2007-01-01
Most of our understanding of habitat use by migrating land birds comes from studies conducted at single, small spatial scales, which may overemphasize the importance of intrinsic habitat factors, such as food availability, in shaping migrant distributions. We believe that a multi-scale approach is essential to assess the influence of factors that control en route habitat use. We determined the relative importance of eight variables, each operating at a habitat-patch, landscape, or regional spatial scale, in explaining the differential use of hardwood forests by Nearctic-Neotropical land birds during migration. We estimated bird densities through transect surveys at sites near the Mississippi coast during spring and autumn migration within landscapes with variable amounts of hardwood forest cover. At a regional scale, migrant density increased with proximity to the coast, which was of moderate importance in explaining bird densities, probably due to constraints imposed on migrants when negotiating the Gulf of Mexico. The amount of hardwood forest cover at a landscape scale was positively correlated with arthropod abundance and had the greatest importance in explaining densities of all migrants, as a group, during spring, and of insectivorous migrants during autumn. Among landscape scales ranging from 500 m to 10 km radius, the densities of migrants were, on average, most strongly and positively related to the amount of hardwood forest cover within a 5 km radius. We suggest that hardwood forest cover at this scale may be an indicator of habitat quality that migrants use as a cue when landing at the end of a migratory flight. At the patch scale, direct measures of arthropod abundance and plant community composition were also important in explaining migrant densities, whereas habitat structure was of little importance. The relative amount of fleshy-fruited trees was positively related and was the most important variable explaining frugivorous migrant density during autumn. Although constraints extrinsic to habitat had a moderate role in explaining migrant distributions, our results are consistent with the view that food availability is the ultimate factor shaping the distributions of birds during stopover. ?? 2007 by the Ecological Society of America.
The modulating effect of education on semantic interference during healthy aging.
Paolieri, Daniela; Marful, Alejandra; Morales, Luis; Bajo, María Teresa
2018-01-01
Aging has traditionally been related to impairments in name retrieval. These impairments have usually been explained by a phonological transmission deficit hypothesis or by an inhibitory deficit hypothesis. This decline can, however, be modulated by the educational level of the sample. This study analyzed the possible role of these approaches in explaining both object and face naming impairments during aging. Older adults with low and high educational level and young adults with high educational level were asked to repeatedly name objects or famous people using the semantic-blocking paradigm. We compared naming when exemplars were presented in a semantically homogeneous or in a semantically heterogeneous context. Results revealed significantly slower rates of both face and object naming in the homogeneous context (i.e., semantic interference), with a stronger effect for face naming. Interestingly, the group of older adults with a lower educational level showed an increased semantic interference effect during face naming. These findings suggest the joint work of the two mechanisms proposed to explain age-related naming difficulties, i.e., the inhibitory deficit and the transmission deficit hypothesis. Therefore, the stronger vulnerability to semantic interference in the lower educated older adult sample would possibly point to a failure in the inhibitory mechanisms in charge of interference resolution, as proposed by the inhibitory deficit hypothesis. In addition, the fact that this interference effect was mainly restricted to face naming and not to object naming would be consistent with the increased age-related difficulties during proper name retrieval, as suggested by the transmission deficit hypothesis.
The modulating effect of education on semantic interference during healthy aging
Morales, Luis; Bajo, María Teresa
2018-01-01
Aging has traditionally been related to impairments in name retrieval. These impairments have usually been explained by a phonological transmission deficit hypothesis or by an inhibitory deficit hypothesis. This decline can, however, be modulated by the educational level of the sample. This study analyzed the possible role of these approaches in explaining both object and face naming impairments during aging. Older adults with low and high educational level and young adults with high educational level were asked to repeatedly name objects or famous people using the semantic-blocking paradigm. We compared naming when exemplars were presented in a semantically homogeneous or in a semantically heterogeneous context. Results revealed significantly slower rates of both face and object naming in the homogeneous context (i.e., semantic interference), with a stronger effect for face naming. Interestingly, the group of older adults with a lower educational level showed an increased semantic interference effect during face naming. These findings suggest the joint work of the two mechanisms proposed to explain age-related naming difficulties, i.e., the inhibitory deficit and the transmission deficit hypothesis. Therefore, the stronger vulnerability to semantic interference in the lower educated older adult sample would possibly point to a failure in the inhibitory mechanisms in charge of interference resolution, as proposed by the inhibitory deficit hypothesis. In addition, the fact that this interference effect was mainly restricted to face naming and not to object naming would be consistent with the increased age-related difficulties during proper name retrieval, as suggested by the transmission deficit hypothesis. PMID:29370252
NO supplementation for transfusion medicine and cardiovascular applications.
Cabrales, Pedro; Ortiz, Daniel; Friedman, Joel M
Blood transfusions are used to treat reduced O 2 -carrying capacity consequent to anemia. In many cases anemia is caused by a major blood loss, which also creates a state of hypovolemia. Whereas O 2 transport capacity is restored by increasing levels of circulating Hb, transfusion does not resolve the hypoperfusion, the hypoxia and the inflammatory cascades initiated during the anemia and hypovolemia. This explains why blood transfusion is not always an effective treatment and why transfusion of stored blood has been associated with increased morbidity and mortality, especially in patient populations receiving multiple transfusions. Epidemiologic data indicate that adverse events after transfusion are relatively common, having a great impact on the patients outcome and on the costs of public health. In this chapter, we explain why classical transfusion strategies target the reversal of hypoxia only, but do not address the inflammatory cascades initiated during anemic states and the importance of the flow and vascular endothelium interactions. We also establish the relation between red blood cells storage lesions, limited NO bioavailability and transfusion-associated adverse events. Lastly, we explain the potential use of long-lived sources of bioactive NO to reverse the hypoxic inflammatory cascades, promote a sustained increase in tissue perfusion and thereby allow transfusions to achieve their intended goal. The underlying premise is that adverse effects associated with transfusions are intimately linked to vascular dysfunction. Understanding of these mechanisms would lead to novel transfusion medicine strategies to preserve red cell function and to correct for functional changes induced by hemoglobinopathies that affect cell structure and function.
Ben-David, Boaz M; Tewari, Anita; Shakuf, Vered; Van Lieshout, Pascal H H M
2014-01-01
Selective attention, an essential part of daily activity, is often impaired in people with Alzheimer's disease (AD). Usually, it is measured by the color-word Stroop test. However, there is no universal agreement whether performance on the Stroop task changes significantly in AD patients; or if so, whether an increase in Stroop effects reflects a decrease in selective attention, a slowing in generalized speed of processing (SOP), or is the result of degraded color-vision. The current study investigated the impact of AD on Stroop performance and its potential sources in a meta-analysis and mathematical modeling of 18 studies, comparing 637 AD patients with 977 healthy age-matched participants. We found a significant increase in Stroop effects for AD patients, across studies. This AD-related change was associated with a slowing in SOP. However, after correcting for a bias in the distribution of latencies, SOP could only explain a moderate portion of the total variance (25%). Moreover, we found strong evidence for an AD-related increase in the latency difference between naming the font-color and reading color-neutral stimuli (r2 = 0.98). This increase in the dimensional imbalance between color-naming and word-reading was found to explain a significant portion of the AD-related increase in Stroop effects (r2 = 0.87), hinting on a possible sensory source. In conclusion, our analysis highlights the importance of controlling for sensory degradation and SOP when testing cognitive performance and, specifically, selective attention in AD patients. We also suggest possible measures and tools to better test for selective attention in AD.
Fungal Community Responses to Past and Future Atmospheric CO2 Differ by Soil Type
Ellis, J. Christopher; Fay, Philip A.; Polley, H. Wayne; Jackson, Robert B.
2014-01-01
Soils sequester and release substantial atmospheric carbon, but the contribution of fungal communities to soil carbon balance under rising CO2 is not well understood. Soil properties likely mediate these fungal responses but are rarely explored in CO2 experiments. We studied soil fungal communities in a grassland ecosystem exposed to a preindustrial-to-future CO2 gradient (250 to 500 ppm) in a black clay soil and a sandy loam soil. Sanger sequencing and pyrosequencing of the rRNA gene cluster revealed that fungal community composition and its response to CO2 differed significantly between soils. Fungal species richness and relative abundance of Chytridiomycota (chytrids) increased linearly with CO2 in the black clay (P < 0.04, R2 > 0.7), whereas the relative abundance of Glomeromycota (arbuscular mycorrhizal fungi) increased linearly with elevated CO2 in the sandy loam (P = 0.02, R2 = 0.63). Across both soils, decomposition rate was positively correlated with chytrid relative abundance (r = 0.57) and, in the black clay soil, fungal species richness. Decomposition rate was more strongly correlated with microbial biomass (r = 0.88) than with fungal variables. Increased labile carbon availability with elevated CO2 may explain the greater fungal species richness and Chytridiomycota abundance in the black clay soil, whereas increased phosphorus limitation may explain the increase in Glomeromycota at elevated CO2 in the sandy loam. Our results demonstrate that soil type plays a key role in soil fungal responses to rising atmospheric CO2. PMID:25239904
Sundberg, Christopher W; Hunter, Sandra K; Trappe, Scott W; Smith, Carolyn S; Fitts, Robert H
2018-05-28
The mechanisms for the loss in muscle power and increased fatigability with ageing are unresolved. We show that the contractile mechanics of fibres from the vastus lateralis of old men were well-preserved compared to young men, but the selective loss of fast myosin heavy chain (MHC) II muscle was strongly associated with age-related decrements in whole-muscle strength and power. We reveal that the combination of acidosis (H + ) and inorganic phosphate (P i ) is an important mediator of muscle fatigue in humans by inhibiting the low- to high-force state of the cross-bridge cycle and peak power, but the depressive effects of these ions on cross-bridge function were similar in fibres from young and old men. These findings suggest the age-related loss in muscle power is due primarily to the atrophy of fast fibres, but the age-related increased fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i . The purpose of this study was to identify the mechanisms for the loss in muscle power and increased fatigability with ageing by integrating measures of whole-muscle function with single fibre contractile mechanics. After adjusting for the 22% smaller muscle mass in old (73-89 yrs, n = 6) compared with young men (20-29 yrs, n = 6), isometric torque and power output of the knee extensors were, respectively, 38% and 53% lower with age. Fatigability was ∼2.5-fold greater with age and strongly associated with the reductions in the electrically-evoked contractile properties. To test whether cross-bridge mechanisms could explain age-related decrements in knee extensor function, we exposed myofibres (n = 254) from the vastus lateralis to conditions mimicking quiescent muscle and fatiguing levels of H + (pH 6.2) and P i (30 mM). The fatigue-mimicking condition caused marked reductions in force, shortening velocity, and power and inhibited the low- to high-force state of the cross-bridge cycle, confirming non-human studies that these ions act synergistically to impair cross-bridge function. Other than severe age-related atrophy of fast fibres (-55%), contractile function and the depressive effects of the fatigue-mimicking condition did not differ in fibres from young and old men. The selective loss of fast MHC II muscle was strongly associated with the age-related decrease in isometric torque (r = 0.785) and power (r = 0.861). These data suggest that the age-related loss in muscle strength and power is due primarily to the atrophy of fast fibres, but that the age-related increased fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i . This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
A Theory of Age-Dependent Mutation and Senescence
Moorad, Jacob A.; Promislow, Daniel E. L.
2008-01-01
Laboratory experiments show us that the deleterious character of accumulated novel age-specific mutations is reduced and made less variable with increased age. While theories of aging predict that the frequency of deleterious mutations at mutation–selection equilibrium will increase with the mutation's age of effect, they do not account for these age-related changes in the distribution of de novo mutational effects. Furthermore, no model predicts why this dependence of mutational effects upon age exists. Because the nature of mutational distributions plays a critical role in shaping patterns of senescence, we need to develop aging theory that explains and incorporates these effects. Here we propose a model that explains the age dependency of mutational effects by extending Fisher's geometrical model of adaptation to include a temporal dimension. Using a combination of simple analytical arguments and simulations, we show that our model predicts age-specific mutational distributions that are consistent with observations from mutation-accumulation experiments. Simulations show us that these age-specific mutational effects may generate patterns of senescence at mutation–selection equilibrium that are consistent with observed demographic patterns that are otherwise difficult to explain. PMID:18660535
Yao, Shuyang; Kuja-Halkola, Ralf; Thornton, Laura M; Norring, Claes; Almqvist, Catarina; D'Onofrio, Brian M; Lichtenstein, Paul; Långström, Niklas; Bulik, Cynthia M; Larsson, Henrik
2017-09-01
We examined epidemiological associations between anorexia nervosa (AN) and bulimia nervosa (BN) and risks of committing theft and other crimes in a nationwide female population. Females born in Sweden during 1979-1998 (N = 957,106) were followed from age 15 for up to 20 years using information on clinically diagnosed AN and BN (exposures), convictions of theft and other crimes (outcomes), psychiatric comorbidities, and familial relatedness from Swedish national registers. We estimated hazard ratios (HRs) of criminality in exposed versus unexposed females using Cox proportional hazards regressions and explored how comorbidities and unmeasured familial factors explained the associations. The cumulative incidence of convictions of theft (primarily petty theft) and other crimes was higher in exposed females (AN: 11.60% theft, 7.39% other convictions; BN: 17.97% theft, 13.17% other convictions) than in unexposed females (∼5% theft, ∼6% other convictions). The significantly increased risk of being convicted of theft in exposed females (AN: HR = 2.51, 95% confidence interval = [2.29, 2.74], BN: 4.31 [3.68, 5.05]) was partially explained by comorbidities; unmeasured familial factors partially explained the association with convictions of theft in BN but not in AN. Females with BN had a doubled risk of convictions of other crimes, which was partially explained by comorbidities. Individuals with eating disorders had increased risk for convictions of theft and potentially other crimes. Results underscore the importance of regular forensic screening and encourage research on mechanisms underlying the relation between crime and eating disorder psychopathology and efforts to determine how best to address such relation in treatment. © 2017 Wiley Periodicals, Inc.
[Intelligence and the explanation for socio-economic inequalities in health].
Huisman, M; Mackenbach, J P
2007-05-12
Attention is increasingly being paid to the role of cognitive ability to explain socio-economic inequalities in health. The universal socio-economic gradient in health, where each rung lower on the socio-economic ladder implies worse health, has still not been satisfactorily explained scientifically. Because cognitive ability is related to a multitude of social outcomes in a similarly graded manner, hypothesising that cognitive ability plays a major role in health inequalities by socio-economic status is appealing. Recent empirical studies have shown that at least part of socio-economic health inequalities can indeed be explained by differences in cognitive ability. However, this does not imply that we should be pessimistic about future attempts to break the chain that links socio-economic status and cognitive ability with health. During some life stages, environmental factors may be able to influence cognitive ability. Interventions may therefore be targeted in order to optimize these effects. In addition, there is evidence that cognitive ability is correlated with health-related behaviours such as smoking, excessive alcohol consumption and obesity. Therefore, another opportunity for reducing health inequalities related to cognitive ability and socio-economic status would be to develop tailored interventions to improve health-related behaviours in disadvantaged groups. However, the first priority is to further investigate the role of cognitive ability in health inequalities by examining various health outcomes, different age groups and variations across the life course.
Chouchane, Hatem; Krol, Maarten S; Hoekstra, Arjen Y
2018-02-01
Growing water demands put increasing pressure on local water resources, especially in water-short countries. Virtual water trade can play a key role in filling the gap between local demand and supply of water-intensive commodities. This study aims to analyse the dynamics in virtual water trade of Tunisia in relation to environmental and socio-economic factors such as GDP, irrigated land, precipitation, population and water scarcity. The water footprint of crop production is estimated using AquaCrop for six crops over the period 1981-2010. Net virtual water import (NVWI) is quantified at yearly basis. Regression models are used to investigate dynamics in NVWI in relation to the selected factors. The results show that NVWI during the study period for the selected crops is not influenced by blue water scarcity. NVWI correlates in two alternative models to either population and precipitation (model I) or to GDP and irrigated area (model II). The models are better in explaining NVWI of staple crops (wheat, barley, potatoes) than NVWI of cash crops (dates, olives, tomatoes). Using model I, we are able to explain both trends and inter-annual variability for rain-fed crops. Model II performs better for irrigated crops and is able to explain trends significantly; no significant relation is found, however, with variables hypothesized to represent inter-annual variability. Copyright © 2017 Elsevier B.V. All rights reserved.
Struchiner, Claudio Jose; Rocklöv, Joacim; Wilder-Smith, Annelies; Massad, Eduardo
2015-01-01
In Singapore, the frequency and magnitude of dengue epidemics have increased significantly over the past 40 years. It is important to understand the main drivers for the rapid increase in dengue incidence. We studied the relative contributions of putative drivers for the rise of dengue in Singapore: population growth, climate parameters and international air passenger arrivals from dengue endemic countries, for the time period of 1974 until 2011. We used multivariable Poisson regression models with the following predictors: Annual Population Size; Aedes Premises Index; Mean Annual Temperature; Minimum and Maximum Temperature Recorded in each year; Annual Precipitation and Annual Number of Air Passengers arriving from dengue-endemic South-East Asia to Singapore. The relative risk (RR) of the increase in dengue incidence due to population growth over the study period was 42.7, while the climate variables (mean and minimum temperature) together explained an RR of 7.1 (RR defined as risk at the end of the time period relative to the beginning and goodness of fit associated with the model leading to these estimates assessed by pseudo-R2 equal to 0.83). Estimating the extent of the contribution of these individual factors on the increasing dengue incidence, we found that population growth contributed to 86% while the residual 14% was explained by increase in temperature. We found no correlation with incoming air passenger arrivals into Singapore from dengue endemic countries. Our findings have significant implications for predicting future trends of the dengue epidemics given the rapid urbanization with population growth in many dengue endemic countries. It is time for policy-makers and the scientific community alike to pay more attention to the negative impact of urbanization and urban climate on diseases such as dengue. PMID:26322517
Jefferis, Barbara J M H; Power, Chris; Hertzman, Clyde
2002-08-10
To examine the combined effect of social class and weight at birth on cognitive trajectories during school age and the associations between birth weight and educational outcomes through to 33 years. Longitudinal, population based, birth cohort study. 10 845 males and females born during 3-9 March 1958 with information on birth weight, social class, and cognitive tests. Reading, maths, draw a man, copying designs, verbal and non-verbal ability tests at ages 7, 11, and 16, highest qualifications achieved by 33, and trajectories of maths standardised scores at 7-16 years. The outcome of all childhood cognitive tests and educational achievements improved significantly with increasing birth weight. Analysis of maths scores at 7 and of highest qualifications achieved by 33 showed that the relations were robust to adjustment for potential confounding factors. For each kilogram increase in birth weight, maths z score increased by 0.17 (adjusted estimate 0.15, 95% confidence interval 0.10 to 0.21) for males and 0.21 (0.20, 0.14 to 0.25) for females. Trajectories of maths z scores between 7 and 16 years diverged for different social class groups: participants from classes I and II increased their relative position on the score with increasing age, whereas classes IV and V showed a relative decline with increasing age. Birth weight explained much less of the variation in cognition than did social class (range 0.5-1.5% v 2.9-12.5%). The postnatal environment has an overwhelming influence on cognitive function through to early adulthood, but these strong effects do not explain the weaker but independent association with birth weight.
Struchiner, Claudio Jose; Rocklöv, Joacim; Wilder-Smith, Annelies; Massad, Eduardo
2015-01-01
In Singapore, the frequency and magnitude of dengue epidemics have increased significantly over the past 40 years. It is important to understand the main drivers for the rapid increase in dengue incidence. We studied the relative contributions of putative drivers for the rise of dengue in Singapore: population growth, climate parameters and international air passenger arrivals from dengue endemic countries, for the time period of 1974 until 2011. We used multivariable Poisson regression models with the following predictors: Annual Population Size; Aedes Premises Index; Mean Annual Temperature; Minimum and Maximum Temperature Recorded in each year; Annual Precipitation and Annual Number of Air Passengers arriving from dengue-endemic South-East Asia to Singapore. The relative risk (RR) of the increase in dengue incidence due to population growth over the study period was 42.7, while the climate variables (mean and minimum temperature) together explained an RR of 7.1 (RR defined as risk at the end of the time period relative to the beginning and goodness of fit associated with the model leading to these estimates assessed by pseudo-R2 equal to 0.83). Estimating the extent of the contribution of these individual factors on the increasing dengue incidence, we found that population growth contributed to 86% while the residual 14% was explained by increase in temperature. We found no correlation with incoming air passenger arrivals into Singapore from dengue endemic countries. Our findings have significant implications for predicting future trends of the dengue epidemics given the rapid urbanization with population growth in many dengue endemic countries. It is time for policy-makers and the scientific community alike to pay more attention to the negative impact of urbanization and urban climate on diseases such as dengue.
Circadian misalignment increases cardiovascular disease risk factors in humans
Morris, Christopher J.; Purvis, Taylor E.; Hu, Kun; Scheer, Frank A. J. L.
2016-01-01
Shift work is a risk factor for hypertension, inflammation, and cardiovascular disease. This increased risk cannot be fully explained by classic risk factors. One of the key features of shift workers is that their behavioral and environmental cycles are typically misaligned relative to their endogenous circadian system. However, there is little information on the impact of acute circadian misalignment on cardiovascular disease risk in humans. Here we show—by using two 8-d laboratory protocols—that short-term circadian misalignment (12-h inverted behavioral and environmental cycles for three days) adversely affects cardiovascular risk factors in healthy adults. Circadian misalignment increased 24-h systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 3.0 mmHg and 1.5 mmHg, respectively. These results were primarily explained by an increase in blood pressure during sleep opportunities (SBP, +5.6 mmHg; DBP, +1.9 mmHg) and, to a lesser extent, by raised blood pressure during wake periods (SBP, +1.6 mmHg; DBP, +1.4 mmHg). Circadian misalignment decreased wake cardiac vagal modulation by 8–15%, as determined by heart rate variability analysis, and decreased 24-h urinary epinephrine excretion rate by 7%, without a significant effect on 24-h urinary norepinephrine excretion rate. Circadian misalignment increased 24-h serum interleukin-6, C-reactive protein, resistin, and tumor necrosis factor-α levels by 3–29%. We demonstrate that circadian misalignment per se increases blood pressure and inflammatory markers. Our findings may help explain why shift work increases hypertension, inflammation, and cardiovascular disease risk. PMID:26858430
Estimating seat belt effectiveness using matched-pair cohort methods.
Cummings, Peter; Wells, James D; Rivara, Frederick P
2003-01-01
Using US data for 1986-1998 fatal crashes, we employed matched-pair analysis methods to estimate that the relative risk of death among belted compared with unbelted occupants was 0.39 (95% confidence interval (CI) 0.37-0.41). This differs from relative risk estimates of about 0.55 in studies that used crash data collected prior to 1986. Using 1975-1998 data, we examined and rejected three theories that might explain the difference between our estimate and older estimates: (1) differences in the analysis methods; (2) changes related to car model year; (3) changes in crash characteristics over time. A fourth theory, that the introduction of seat belt laws would induce some survivors to claim belt use when they were not restrained, could explain part of the difference in our estimate and older estimates; but even in states without seat belt laws, from 1986 through 1998, the relative risk estimate was 0.45 (95% CI 0.39-0.52). All of the difference between our estimate and older estimates could be explained by some misclassification of seat belt use. Relative risk estimates would move away from 1, toward their true value, if misclassification of both the belted and unbelted decreased over time, or if the degree of misclassification remained constant, as the prevalence of belt use increased. We conclude that estimates of seat belt effects based upon data prior to 1986 may be biased toward 1 by misclassification.
Factors Contributing to Changes in a Deep Approach to Learning in Different Learning Environments
ERIC Educational Resources Information Center
Postareff, Liisa; Parpala, Anna; Lindblom-Ylänne, Sari
2015-01-01
The study explored factors explaining changes in a deep approach to learning. The data consisted of interviews with 12 students from four Bachelor-level courses representing different disciplines. We analysed and compared descriptions of students whose deep approach either increased, decreased or remained relatively unchanged during their courses.…
Does the Students' Preferred Pedagogy Relate to Their Ethnicity: UK and Asian Experience
ERIC Educational Resources Information Center
Winch, Junko
2016-01-01
An increasing number of international students, whose culture of teaching and learning practices are very different from UK students, are studying at British universities. This study investigates multicultural students' preferences using two different teaching approaches in the 2009/2010 academic year, which is explained in the framework of this…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lincoln, Don
One of the oddest features of special relativity is the inability to go faster than the speed of light and this is absolutely true. The most common explanation is that the mass of an object increases with speed, but this particular explanation simply isn’t true. In this video, Fermilab’s Dr. Don Lincoln explains the truth behind this.
Technologically and Artistically Enhanced Multi-Sensory Computer-Programming Education
ERIC Educational Resources Information Center
Katai, Zoltan; Toth, Laszlo
2010-01-01
Over the last decades more and more research has analysed relatively new or rediscovered teaching-learning concepts like blended, hybrid, multi-sensory or technologically enhanced learning. This increased interest in these educational forms can be explained by new exciting discoveries in brain research and cognitive psychology, as well as by the…
ERIC Educational Resources Information Center
Eisenberg, Miriam H.; Fitz, Caroline C.
2014-01-01
Objective: "Drunkorexia," limiting food intake before alcohol consumption, increases college students' risk for negative alcohol-related health consequences. The current study tested whether (1) women engage in drunkorexia more frequently than men; (2) weight control motivations explain sex differences in drunkorexia; and (3) among…
An Effective Model to Increase Student Attitude and Achievement: Narrative Including Analogies
ERIC Educational Resources Information Center
Akkuzu, Nalan; Akcay, Husamettin
2011-01-01
This study describes the analogical models and narratives used to introduce and teach Grade 9 chemical covalent compounds which are relatively abstract and difficult for students. We explained each model's development during the lessons and analyzed understanding students derived from these learning materials. In this context, achievement,…
USDA-ARS?s Scientific Manuscript database
Threonine is an essential amino acid necessary for synthesis of gut mucins that form the protective intestinal mucous layer. In premature infants, this function might be compromised leading to necrotizing enterocolitis (NEC). We hypothesized that enteral feeding with colostrum, relative to infant fo...
Stressing Academia? Stress-as-Offence-to-Self at Danish Universities
ERIC Educational Resources Information Center
Opstrup, Niels; Pihl-Thingvad, Signe
2016-01-01
Academic work has traditionally been seen as relatively stress free. However, a growing number of studies have reported increases in occupational stress experienced by university researchers. In order to explain stress among this group, we build on a new perspective in occupational stress research: the so-called stress-as-offence-to-self…
Error-based analysis of optimal tuning functions explains phenomena observed in sensory neurons.
Yaeli, Steve; Meir, Ron
2010-01-01
Biological systems display impressive capabilities in effectively responding to environmental signals in real time. There is increasing evidence that organisms may indeed be employing near optimal Bayesian calculations in their decision-making. An intriguing question relates to the properties of optimal encoding methods, namely determining the properties of neural populations in sensory layers that optimize performance, subject to physiological constraints. Within an ecological theory of neural encoding/decoding, we show that optimal Bayesian performance requires neural adaptation which reflects environmental changes. Specifically, we predict that neuronal tuning functions possess an optimal width, which increases with prior uncertainty and environmental noise, and decreases with the decoding time window. Furthermore, even for static stimuli, we demonstrate that dynamic sensory tuning functions, acting at relatively short time scales, lead to improved performance. Interestingly, the narrowing of tuning functions as a function of time was recently observed in several biological systems. Such results set the stage for a functional theory which may explain the high reliability of sensory systems, and the utility of neuronal adaptation occurring at multiple time scales.
Children's patterns of reasoning about reading and addition concepts.
Farrington-Flint, Lee; Canobi, Katherine H; Wood, Clare; Faulkner, Dorothy
2010-06-01
Children's reasoning was examined within two educational contexts (word reading and addition) so as to understand the factors that contribute to relational reasoning in the two domains. Sixty-seven 5- to 7-year-olds were given a series of related words to read or single-digit addition items to solve (interspersed with unrelated items). The frequency, accuracy, and response times of children's self-reports on the conceptually related items provided a measure of relational reasoning, while performance on the unrelated addition and reading items provided a measure of procedural skill. The results indicated that the children's ability to use conceptual relations to solve both reading and addition problems enhanced speed and accuracy levels, increased with age, and was related to procedural skill. However, regression analyses revealed that domain-specific competencies can best explain the use of conceptual relations in both reading and addition. Moreover, a cluster analysis revealed that children differ according to the academic domain in which they first apply conceptual relations and these differences are related to individual variation in their procedural skills within these particular domains. These results highlight the developmental significance of relational reasoning in the context of reading and addition and underscore the importance of concept-procedure links in explaining children's literacy and arithmetical development.
Geisler, Corinna; Braun, Wiebke; Pourhassan, Maryam; Schweitzer, Lisa; Glüer, Claus-Christian; Bosy-Westphal, Anja; Müller, Manfred J.
2016-01-01
Age-related changes in organ and tissue masses may add to changes in the relationship between resting energy expenditure (REE) and fat free mass (FFM) in normal and overweight healthy Caucasians. Secondary analysis using cross-sectional data of 714 healthy normal and overweight Caucasian subjects (age 18–83 years) with comprehensive information on FFM, organ and tissue masses (as assessed by magnetic resonance imaging (MRI)), body density (as assessed by Air Displacement Plethysmography (ADP)) and hydration (as assessed by deuterium dilution (D2O)) and REE (as assessed by indirect calorimetry). High metabolic rate organs (HMR) summarized brain, heart, liver and kidney masses. Ratios of HMR organs and muscle mass (MM) in relation to FFM were considered. REE was calculated (REEc) using organ and tissue masses times their specific metabolic rates. REE, FFM, specific metabolic rates, the REE-FFM relationship, HOMA, CRP, and thyroid hormone levels change with age. The age-related decrease in FFM explained 59.7% of decreases in REE. Mean residuals of the REE-FFM association were positive in young adults but became negative in older subjects. When compared to young adults, proportions of MM to FFM decreased with age, whereas contributions of liver and heart did not differ between age groups. HOMA, TSH and inflammation (plasma CRP-levels) explained 4.2%, 2.0% and 1.4% of the variance in the REE-FFM residuals, but age and plasma T3-levels had no effects. HMR to FFM and MM to FFM ratios together added 11.8% on to the variance of REE-FFM residuals. Differences between REE and REEc increased with age, suggesting age-related changes in specific metabolic rates of organs and tissues. This bias was partly explained by plasmaT3-levels. Age-related changes in REE are explained by (i) decreases in fat free mass; (ii) a decrease in the contributions of organ and muscle masses to FFM; and (iii) decreases in specific organ and tissue metabolic rates. Age-dependent changes in the REE-FFMassociation are explained by composition of FFM, inflammation and thyroid hormones. PMID:27258302
Geisler, Corinna; Braun, Wiebke; Pourhassan, Maryam; Schweitzer, Lisa; Glüer, Claus-Christian; Bosy-Westphal, Anja; Müller, Manfred J
2016-06-01
Age-related changes in organ and tissue masses may add to changes in the relationship between resting energy expenditure (REE) and fat free mass (FFM) in normal and overweight healthy Caucasians. Secondary analysis using cross-sectional data of 714 healthy normal and overweight Caucasian subjects (age 18-83 years) with comprehensive information on FFM, organ and tissue masses (as assessed by magnetic resonance imaging (MRI)), body density (as assessed by Air Displacement Plethysmography (ADP)) and hydration (as assessed by deuterium dilution (D₂O)) and REE (as assessed by indirect calorimetry). High metabolic rate organs (HMR) summarized brain, heart, liver and kidney masses. Ratios of HMR organs and muscle mass (MM) in relation to FFM were considered. REE was calculated (REEc) using organ and tissue masses times their specific metabolic rates. REE, FFM, specific metabolic rates, the REE-FFM relationship, HOMA, CRP, and thyroid hormone levels change with age. The age-related decrease in FFM explained 59.7% of decreases in REE. Mean residuals of the REE-FFM association were positive in young adults but became negative in older subjects. When compared to young adults, proportions of MM to FFM decreased with age, whereas contributions of liver and heart did not differ between age groups. HOMA, TSH and inflammation (plasma CRP-levels) explained 4.2%, 2.0% and 1.4% of the variance in the REE-FFM residuals, but age and plasma T3-levels had no effects. HMR to FFM and MM to FFM ratios together added 11.8% on to the variance of REE-FFM residuals. Differences between REE and REEc increased with age, suggesting age-related changes in specific metabolic rates of organs and tissues. This bias was partly explained by plasmaT3-levels. Age-related changes in REE are explained by (i) decreases in fat free mass; (ii) a decrease in the contributions of organ and muscle masses to FFM; and (iii) decreases in specific organ and tissue metabolic rates. Age-dependent changes in the REE-FFMassociation are explained by composition of FFM, inflammation and thyroid hormones.
Brennan, Angela K.; Cross, Paul C.; Higgs, Megan D.; Edwards, W. Henry; Scurlock, Brandon M.; Creel, Scott
2014-01-01
Understanding how animal density is related to pathogen transmission is important to develop effective disease control strategies, but requires measuring density at a scale relevant to transmission. However, this is not straightforward or well-studied among large mammals with group sizes that range several orders of magnitude or aggregation patterns that vary across space and time. To address this issue, we examined spatial variation in elk (Cervus canadensis) aggregation patterns and brucellosis across 10 regions in the Greater Yellowstone Area where previous studies suggest the disease may be increasing. We hypothesized that rates of increasing brucellosis would be better related to the frequency of large groups than mean group size or population density, but we examined whether other measures of density would also explain rising seroprevalence. To do this, we measured wintering elk density and group size across multiple spatial and temporal scales from monthly aerial surveys. We used Bayesian hierarchical models and 20 years of serologic data to estimate rates of increase in brucellosis within the 10 regions, and to examine the linear relationships between these estimated rates of increase and multiple measures of aggregation. Brucellosis seroprevalence increased over time in eight regions (one region showed an estimated increase from 0.015 in 1991 to 0.26 in 2011), and these rates of increase were positively related to all measures of aggregation. The relationships were weaker when the analysis was restricted to areas where brucellosis was present for at least two years, potentially because aggregation was related to disease-establishment within a population. Our findings suggest that (1) group size did not explain brucellosis increases any better than population density and (2) some elk populations may have high densities with small groups or lower densities with large groups, but brucellosis is likely to increase in either scenario. In this case, any one control method such as reducing population density or group size may not be sufficient to reduce transmission. This study highlights the importance of examining the density-transmission relationship at multiple scales and across populations before broadly applying disease control strategies.
[Associations between mortality and alcohol consumption in Lithuanian population].
Grabauskas, Vilius; Prochorskas, Remigijus; Veryga, Aurelijus
2009-01-01
The objective of the study was to assess alcohol-related mortality that potentially might explain an increasing trend in overall mortality of Lithuanian population, which started after 2000 and peaked in 2005. An empiric analysis of national mortality and other statistical data as well as their international comparisons. An analysis of available data clearly indicates that a decline in mortality in 1998-2000, i.e. during the beginning of the National Programme of Health, as well as its increase in 2001 and 2005 were predominantly determined by cause-specific deaths of two groups: deaths from diseases of the circulatory system (mainly ischemic heart disease) and alcohol consumption-related deaths (liver cirrhosis, accidental poisoning by alcohol, accidents, etc.). A certain proportion of deaths, which were caused by alcohol, were wrongly assigned to the deaths from diseases of the circulatory system due to uncertainties in filling-in death certificates. By approximate estimates, at least one-quarter of increase in all-cause mortality between 2002-2004 and 2005-2007 could be explained by an increase in alcohol consumption, accounting for additional 880 deaths on average per year. In the year 2007, 12.6% (n=5760) of all deaths were somehow related to alcohol consumption. A comparative analysis demonstrated that mortality and alcohol consumption trends were going in parallel over the last decade. The systemic decline in mortality observed in Lithuania from 1995 stopped in 2000 after a decrease in alcohol taxes, which resulted in an increase in alcohol accessibility and consumption. An average annual increase in alcohol consumption over the period of 2001-2004 was 7%; it increased up to 17% in 2005 and accounted for 12% annual increase on average within 2005-2007. Negative trends in alcohol-related morbidity and mortality in Lithuanian population most notably registered in 2001 and 2005 were largely influenced by uncontrollable increase in alcohol consumption over the last decade. Economic and commercial arguments in decision-making process that neglected health interest of Lithuanian population (decrease of alcohol taxes in 1999, other factors increasing alcohol accessibility and consumption) were those counteracting the implementation of balanced health policy in the country.
Carlson, Jordan A; Sallis, James F; Conway, Terry L; Saelens, Brian E; Frank, Lawrence D; Kerr, Jacqueline; Cain, Kelli L; King, Abby C
2012-01-01
To evaluate ecological model predictions of cross-level interactions among psychosocial and environmental correlates of physical activity in 719 community-dwelling older adults in the Baltimore, Maryland and Seattle, Washington areas during 2005-2008. Walkability, access to parks and recreation facilities and moderate-to-vigorous physical activity (MVPA) minutes per week (min/week) were measured objectively. Neighborhood aesthetics, walking facilities, social support, self-efficacy, barriers and transportation and leisure walking min/week were self-reported. Walkability interacted with social support in explaining total MVPA (B=13.71) and with social support (B=7.90), self-efficacy (B=7.66) and barriers (B=-8.26) in explaining walking for transportation. Aesthetics interacted with barriers in explaining total MVPA (B=-12.20) and walking facilities interacted with self-efficacy in explaining walking for leisure (B=-10.88; Ps<.05). Summarizing across the interactions, living in a supportive environment (vs. unsupportive) was related to 30-59 more min/week of physical activity for participants with more positive psychosocial attributes, but only 0-28 more min/week for participants with less positive psychosocial attributes. Results supported synergistic interactions between built environment and psychosocial factors in explaining physical activity among older adults. Findings suggest multilevel interventions may be most effective in increasing physical activity. Copyright © 2011 Elsevier Inc. All rights reserved.
Szoboszlay, Márton; Dohrmann, Anja B; Poeplau, Christopher; Don, Axel; Tebbe, Christoph C
2017-12-01
Land-use and their change have dramatic consequences for above-ground biodiversity, but their impact on soil microbial communities is poorly understood. In this study, soils from 19 European sites representing conversion of croplands to grasslands or forests and of grasslands to croplands or forests were characterized for microbial abundance and bacterial diversity. The abundance of Bacteria and Fungi but not Archaea responded to land-use change. Site was the major determinant of the soil bacterial community structure, explaining 32% of the variation in 16S rRNA gene diversity. While the quantity of soil organic carbon (SOC) only explained 5% of the variation, SOC when differentiated by its quality could explain 22%. This was similar to the impact of soil pH (21%) and higher than that of land-use type (15%). Croplands had the highest bacterial diversity. Converting croplands to grassland caused an increase of Verrucomicrobia; croplands to forest increased Rhizobiales but decreased Bacteroidetes and Nitrospirae; and grasslands to cropland increased Gemmatimonadetes but decreased Verrucomicrobia and Planctomycetes. Network analysis identified associations between particular SOC fractions and specific bacterial taxa. We conclude that land-use-related effects on soil microorganisms can be consistently observed across a continental scale. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Safety margins in older adults increase with improved control of a dynamic object
Hasson, Christopher J.; Sternad, Dagmar
2014-01-01
Older adults face decreasing motor capabilities due to pervasive neuromuscular degradations. As a consequence, errors in movement control increase. Thus, older individuals should maintain larger safety margins than younger adults. While this has been shown for object manipulation tasks, several reports on whole-body activities, such as posture and locomotion, demonstrate age-related reductions in safety margins. This is despite increased costs for control errors, such as a fall. We posit that this paradox could be explained by the dynamic challenge presented by the body or also an external object, and that age-related reductions in safety margins are in part due to a decreased ability to control dynamics. To test this conjecture we used a virtual ball-in-cup task that had challenging dynamics, yet afforded an explicit rendering of the physics and safety margin. The hypotheses were: (1) When manipulating an object with challenging dynamics, older adults have smaller safety margins than younger adults. (2) Older adults increase their safety margins with practice. Nine young and 10 healthy older adults practiced moving the virtual ball-in-cup to a target location in exactly 2 s. The accuracy and precision of the timing error quantified skill, and the ball energy relative to an escape threshold quantified the safety margin. Compared to the young adults, older adults had increased timing errors, greater variability, and decreased safety margins. With practice, both young and older adults improved their ability to control the object with decreased timing errors and variability, and increased their safety margins. These results suggest that safety margins are related to the ability to control dynamics, and may explain why in tasks with simple dynamics older adults use adequate safety margins, but in more complex tasks, safety margins may be inadequate. Further, the results indicate that task-specific training may improve safety margins in older adults. PMID:25071566
Courant, Sabrina; Fortin, Daniel
2010-06-01
Herbivores commonly base their foraging decisions not only on the intrinsic characteristics of plants, but also on the attributes of neighboring species. Although herbivores commonly orient their food choices toward the maximization of energy intake, the impact of such choices on neighboring plants remains largely unexplored. We evaluated whether foraging decisions by herbivores aiming at a rapid intake of digestible energy could explain multiple neighboring effects in complex swards. Specifically, we assessed how spatial patterns of occurrence of Carex atherodes, a highly profitable sedge species, could control the risk of bison (Bison bison) herbivory for seven other plant species. The foraging behavior of 70 free-ranging bison was evaluated in their natural environment during summer, and then related to plant characteristics. We used this information to estimate the instantaneous intake rate of digestible energy at individual feeding stations. We found that neighbor contrast defense and associational susceptibility can both be explained by simple foraging rules of energy maximization. Energy gains were higher when C. atherodes was consumed while avoiding the species for which we detected neighbor contrast defense. The lower intake rate associated with their consumption was due to an increase in handling time caused by their small size relative to C. atherodes. Bison also had higher energy gains by consuming instead of avoiding the plant species that experienced associational susceptibility. Because most of these plants were at least as tall as C. atherodes, their presence increased the heterogeneity of the grazed stratum. Avoiding their consumption increased handling time thereby reducing the instantaneous rate of energy intake. Overall, we found that bison adjust their fine-scale foraging decisions to vertical and horizontal sward structures in a way that maximizes their energy intake rate. Energy maximization principles thus provide a valuable framework to evaluate a broad-range of neighboring effects for prey faced with generalist consumers.
Maternal risk factors in fetal alcohol syndrome: provocative and permissive influences.
Abel, E L; Hannigan, J H
1995-01-01
We present an hypothesis integrating epidemiological, clinical case, and basic biomedical research to explain why only relatively few women who drink alcohol during pregnancy give birth to children with alcohol-related birth defects (ARBDs), in particular, Fetal Alcohol Syndrome (FAS). We argue that specific sociobehavioral risk factors, e.g., low socioeconomic status, are permissive for FAS in that they provide the context for increased vulnerability. We illustrate how these permissive factors are related to biological factors, e.g., decreased antioxidant status, which in conjunction with alcohol, provoke FAS/ARBDs in vulnerable fetuses. We propose an integrative heuristic model hypothesizing that these permissive and provocative factors increase the likelihood of FAS/ARBDs because they potentiate two related mechanisms of alcohol-induced teratogenesis, specifically, maternal/fetal hypoxia and free radical formation.
Potosnak, Mark J; Lestourgeon, Lauren; Nunez, Othon
2014-05-15
Including algorithms to account for the suppression of isoprene emission by elevated CO2 concentration affects estimates of global isoprene emission for future climate change scenarios. In this study, leaf-level measurements of isoprene emission were made to determine the short-term interactive effect of leaf temperature and CO2 concentration. For both greenhouse plants and plants grown under field conditions, the suppression of isoprene emission was reduced by increasing leaf temperature. For each of the four different tree species investigated, aspen (Populus tremuloides Michx.), cottonwood (Populus deltoides W. Bartram ex Marshall), red oak (Quercus rubra L.), and tundra dwarf willow (Salix pulchra Cham.), the suppression of isoprene by elevated CO2 was eliminated at increased temperature, and the maximum temperature where suppression was observed ranged from 25 to 35°C. Hypotheses proposed to explain the short-term suppression of isoprene emission by increased CO2 concentration were tested against this observation. Hypotheses related to cofactors in the methylerythritol phosphate (MEP) pathway were consistent with reduced suppression at elevated leaf temperature. Also, reduced solubility of CO2 with increased temperature can explain the reduced suppression for the phosphoenolpyruvate (PEP) carboxylase competition hypothesis. Some global models of isoprene emission include the short-term suppression effect, and should be modified to include the observed interaction. If these results are consistent at longer timescales, there are implications for predicting future global isoprene emission budgets and the reduced suppression at increased temperature could explain some of the variable responses observed in long-term CO2 exposure experiments. Copyright © 2014 Elsevier B.V. All rights reserved.
Comics as an educational tool for children with juvenile idiopathic arthritis.
Mendelson, Amir; Rabinowicz, Noa; Reis, Yonit; Amarilyo, Gil; Harel, Liora; Hashkes, Philip J; Uziel, Yosef
2017-09-02
This study examined whether the comic book Neta and the Medikidz Explain JIA would improve disease-related knowledge and treatment adherence among patients with juvenile idiopathic arthritis (JIA). In this prospective cohort study, JIA patients answered 20 multiple-choice knowledge questions about their disease, before and after reading the comic book. Demographic, clinical, health-related quality of life and adherence data were recorded and correlated to the responses. We studied 61 patients with a mean age of 14 ± 3.3 (range 8-18) years, 67% female, 83% Jewish and 17% non-Jewish. Thirty-nine percent had oligoarthritis, 13% systemic, 32% polyarthritis 11% psoriatic and 5% enthesitis-related type JIA. The disease was active in 46%, 40% were treated with biologics/disease modifying anti-rheumatic drugs, and 34% were in remission on medication. Among the 53 patients who completed before and after quizzes, average score increased from 63 to 80% (P < 0.001). Non-Jewish patients initially scored lower than Jewish patients (48%), but their score increased to 79% after reading the comic book. Twenty-seven patients who also completed the quiz 1 year after the first reading retained their knowledge (79%). We did not find a statistically significant correlation between knowledge and age, sex, disease subtype, or Child Health Questionnaire quality of life scores. Adherence to medication use, physical therapy and rheumatology clinic visits were high at baseline; thus, these did not change after reading the comic. The comic booklet Neta and the Medikidz Explain JIA is a good educational tool for increasing disease-related knowledge in children with JIA.
Mutagenic potential of water from Pelotas Creek in Rio Grande do Sul, Brazil.
Santos, T C O; Maciel, L F; Leal, K S; Bender, A E N; Paiva, T S; Garcias, G L; Martino-Roth, M G
2009-09-01
Water resource degradation is one of mankind's greatest worries, as it causes direct and indirect damage to the associated biota. We initiated a water monitoring study in Pelotas Creek in 2003 in order to assess the mutagenic effect of the creek's waters. Allium cepa cells exposed to water samples and a chronically exposed macrophyte were analyzed, through evaluation of the mitotic index, mitotic anomalies, interphase anomalies, and total anomalies. Five points were chosen along the lower course of Pelotas Creek, from which water samples and floating pennywort (Hydrocotyle ranunculoides, Apiaceae) were collected in 2006 and 2007. The enteric bacterium Escherichia coli was found at all sampling points; in the physical-chemical analysis, a few variables exceeded permitted limits, pH (from 6 to 9), chloride (250 mg/L), hardness (from 10 to 200 mg CaCO(3)/L), and conductivity (100 microOmega/cm). There was an increased number of cytogenetic anomalies in exposed A. cepa cells and in the pennywort in 2006 relative to 2007, which may be explained by the increased rainfall, which was three times greater in 2007 at some stations than in 2006.Omega/cm). There was an increased number of cytogenetic anomalies in exposed A. cepa cells and in the pennywort in 2006 relative to 2007, which may be explained by the increased rainfall, which was three times greater in 2007 at some stations than in 2006.
Castro, Juan M.; García-Espinosa, Victoria; Curcio, Santiago; Arana, Maite; Chiesa, Pedro; Giachetto, Gustavo; Zócalo, Yanina; Bia, Daniel
2016-01-01
The aims were to determine if childhood obesity is associated with increased central aortic blood pressure (BP) and to characterize haemodynamic and vascular changes associated with BP changes in obese children and adolescents by means of analyzing changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR), and net and relative contributions of reflected waves to the aortic pulse wave amplitude. We included 117 subjects (mean/range age: 10 (5–15) years, 49 females), who were obese (OB) or had normal weight (NW). Peripheral and central aortic BP, PWV, and pulse wave-derived parameters (augmentation index, amplitude of forward and backward components) were measured with tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). With independence of the presence of dyslipidemia, hypertension, or sedentarism, the aortic systolic and pulse BP were higher in OB than in NW subjects. The increase in central BP could not be explained by the elevation in the relative contribution of reflections to the aortic pressure wave and higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP could be explained by an increase in the amplitude of both incident and reflect wave components associated to augmented SV and/or PWV. PMID:26881081
Katz-Wise, Sabra L; Jun, Hee-Jin; Corliss, Heather L; Jackson, Benita; Haines, Jess; Austin, S Bryn
2014-06-01
This research aimed to explain sexual orientation disparities in body mass index (BMI) by examining child abuse history, weight-related behaviors, and sociodemographics. We used data from 7,960 females and 5,992 males from the prospective Growing Up Today Study over nine waves between 1996 (ages 12-14 years) and 2007 (ages 20-25 years). Using repeated measures of BMI (kg/m(2)) as a continuous outcome, gender-stratified latent quadratic growth models adjusted for child abuse history, weight-related behaviors, and sociodemographics. BMI at age 17 years (intercept) and 1-year change in BMI (slope) are reported. Bisexual females had higher BMI at age 17 years (β = 1.59, 95% CI = 1.00-2.18) and displayed greater one-year increases in BMI (β = .09, 95% CI = .03-.14), compared with completely heterosexual females. Gay males displayed smaller 1-year increases in BMI (β = -.19, 95% CI = -.25 to -.12), compared with completely heterosexual males. No sexual orientation differences in BMI at age 17 years were observed for males, but gay males' BMI at age 25 was less than completely heterosexual males' BMI by 2 units. Among females, sexual orientation differences remained but were slightly attenuated after controlling for child abuse history, weight-related behaviors, and sociodemographics. Among males, the addition of child abuse and weight-related behaviors did not change the estimated difference in 1-year BMI increases. Sexual orientation differences in BMI were partly explained by child abuse and weight-related behaviors in females. More research is needed to explore additional drivers of these disparities among both females and males. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Vegetation responses to sagebrush-reduction treatments measured by satellites
Johnston, Aaron; Beever, Erik; Merkle, Jerod A.; Chong, Geneva W.
2018-01-01
Time series of vegetative indices derived from satellite imagery constitute tools to measure ecological effects of natural and management-induced disturbances to ecosystems. Over the past century, sagebrush-reduction treatments have been applied widely throughout western North America to increase herbaceous vegetation for livestock and wildlife. We used indices from satellite imagery to 1) quantify effects of prescribed-fire, herbicide, and mechanical treatments on vegetative cover, productivity, and phenology, and 2) describe how vegetation changed over time following these treatments. We hypothesized that treatments would increase herbaceous cover and accordingly shift phenologies towards those typical of grass-dominated systems. We expected prescribed burns would lead to the greatest and most-prolonged effects on vegetative cover and phenology, followed by herbicide and mechanical treatments. Treatments appeared to increase herbaceous cover and productivity, which coincided with signs of earlier senescence − signals expected of grass-dominated systems, relative to sagebrush-dominated systems. Spatial heterogeneity for most phenometrics was lower in treated areas relative to controls, which suggested treatment-induced homogenization of vegetative communities. Phenometrics that explain spring migrations of ungulates mostly were unaffected by sagebrush treatments. Fire had the strongest effect on vegetative cover, and yielded the least evidence for sagebrush recovery. Overall, treatment effects were small relative to those reported from field-based studies for reasons most likely related to sagebrush recovery, treatment specification, and untreated patches within mosaicked treatment applications. Treatment effects were also small relative to inter-annual variation in phenology and productivity that was explained by temperature, snowpack, and growing-season precipitation. Our results indicated that cumulative NDVI, late-season phenometrics, and spatial heterogeneity of several phenometrics may serve as useful indicators of vegetative change in sagebrush ecosystems.
Genetic progress in multistage dairy cattle breeding schemes using genetic markers.
Schrooten, C; Bovenhuis, H; van Arendonk, J A M; Bijma, P
2005-04-01
The aim of this paper was to explore general characteristics of multistage breeding schemes and to evaluate multistage dairy cattle breeding schemes that use information on quantitative trait loci (QTL). Evaluation was either for additional genetic response or for reduction in number of progeny-tested bulls while maintaining the same response. The reduction in response in multistage breeding schemes relative to comparable single-stage breeding schemes (i.e., with the same overall selection intensity and the same amount of information in the final stage of selection) depended on the overall selection intensity, the selection intensity in the various stages of the breeding scheme, and the ratio of the accuracies of selection in the various stages of the breeding scheme. When overall selection intensity was constant, reduction in response increased with increasing selection intensity in the first stage. The decrease in response was highest in schemes with lower overall selection intensity. Reduction in response was limited in schemes with low to average emphasis on first-stage selection, especially if the accuracy of selection in the first stage was relatively high compared with the accuracy in the final stage. Closed nucleus breeding schemes in dairy cattle that use information on QTL were evaluated by deterministic simulation. In the base scheme, the selection index consisted of pedigree information and own performance (dams), or pedigree information and performance of 100 daughters (sires). In alternative breeding schemes, information on a QTL was accounted for by simulating an additional index trait. The fraction of the variance explained by the QTL determined the correlation between the additional index trait and the breeding goal trait. Response in progeny test schemes relative to a base breeding scheme without QTL information ranged from +4.5% (QTL explaining 5% of the additive genetic variance) to +21.2% (QTL explaining 50% of the additive genetic variance). A QTL explaining 5% of the additive genetic variance allowed a 35% reduction in the number of progeny tested bulls, while maintaining genetic response at the level of the base scheme. Genetic progress was up to 31.3% higher for schemes with increased embryo production and selection of embryos based on QTL information. The challenge for breeding organizations is to find the optimum breeding program with regard to additional genetic progress and additional (or reduced) cost.
NASA Technical Reports Server (NTRS)
Naud, Catherine M.; Posselt, Derek J.; van den Heever, Susan C.
2015-01-01
The distribution of cloud and precipitation properties across oceanic extratropical cyclone cold fronts is examined using four years of combined CloudSat radar and CALIPSO lidar retrievals. The global annual mean cloud and precipitation distributions show that low-level clouds are ubiquitous in the post frontal zone while higher-level cloud frequency and precipitation peak in the warm sector along the surface front. Increases in temperature and moisture within the cold front region are associated with larger high-level but lower mid-/low level cloud frequencies and precipitation decreases in the cold sector. This behavior seems to be related to a shift from stratiform to convective clouds and precipitation. Stronger ascent in the warm conveyor belt tends to enhance cloudiness and precipitation across the cold front. A strong temperature contrast between the warm and cold sectors also encourages greater post-cold-frontal cloud occurrence. While the seasonal contrasts in environmental temperature, moisture, and ascent strength are enough to explain most of the variations in cloud and precipitation across cold fronts in both hemispheres, they do not fully explain the differences between Northern and Southern Hemisphere cold fronts. These differences are better explained when the impact of the contrast in temperature across the cold front is also considered. In addition, these large-scale parameters do not explain the relatively large frequency in springtime post frontal precipitation.
Bergstedt, Roger A.; Swink, William D.
1995-01-01
We used lengths and weights of 2367 live parasitic-phase sea lampreys (Petromyzon marinus) collected from Lake Huron, 1984–1990, to calculate their mean size at half-month intervals. Growth in weight was linear during June through September; increments averaged 11.1 g per half month. Growth increased sharply in October to several times the summer rate. We speculate that the increase in growth in October is explained partly by water temperature and partly by an increase in appetite related to the onset of gonadal development. The greater compression of biomass accumulation in autumn than has been previously demonstrated better explains the autumn pulse of sea lamprey induced host mortality. Based on the seasonal pattern of growth and on recaptures of marked sea lampreys, we conclude that landlocked individuals grow to adult size and mature in one parasitic growth year. Regressions of weight (grams) on total length (millimetres) differed significantly among months, and the season of collection must be considered in predicting weight from length.
Could anterior papillary muscle partial necrosis explain early mitral valve repair failure?
Pozzi, Matteo; Generali, Tommaso; Henaine, Roland; Mitchell, Julia; Lemaire, Anais; Chiari, Pascal; Fran, Jean; Obadia, Jean François
2014-09-01
Standardized techniques of mitral valve repair (MVR) have recently witnessed the introduction of a 'respect rather than resect' concept, the strategy of which involves the use of artificial chordae. MVR displays several advantages over mitral valve replacement in degenerative mitral regurgitation (MR), but the risk of reoperation for MVR failure must be taken into account. Different mechanisms could be advocated as the leading cause of MVR failure; procedure-related mechanisms are usually involved in early MVR failure, while valve-related mechanisms are common in late failure. Here, the case is reported of an early failure of MVR using artificial chordae that could be explained by an unusual procedure-related mechanism, namely anterior papillary muscle necrosis. MVR failure is a well-known complication after surgical repair of degenerative MR, but anterior papillary muscle partial necrosis might also be considered a possible mechanism of procedure-related MVR failure, especially when considering the increasing use of artificial chordae. Owing to the encouraging results obtained, mitral valve re-repair might be considered a viable solution, but must be selected after only a meticulous evaluation of the underlying mechanism of MVR failure.
Association between obesity-related biomarkers and cognitive and motor development in infants.
Camargos, Ana Cristina R; Mendonça, Vanessa A; Oliveira, Katherine S C; de Andrade, Camila Alves; Leite, Hércules Ribeiro; da Fonseca, Sueli Ferreira; Vieira, Erica Leandro Marciano; Teixeira Júnior, Antônio Lúcio; Lacerda, Ana Cristina Rodrigues
2017-05-15
This study aimed to verify the association between obesity-related biomarkers and cognitive and motor development in infants between 6 and 24 months of age. A cross-sectional study was conducted with 50 infants and plasma levels of leptin, adiponectin, resistin, soluble tumor necrosis factor receptors 1 and 2 (sTNFR1 and sTNFR2), chemokines, brain-derived neurotrophic factor (BDNF), serum cortisol and redox status were measured. The Bayley-III test was utilized to evaluate cognitive and motor development, and multiple linear stepwise regression models were performed to verify the association between selected biomarkers and cognitive and motor development. A significant association was found among plasma leptin and sTNFR1 levels with cognitive composite scores, and these two independents variables together explained 37% of the variability of cognitive composite scores (p=0.001). Only plasma sTNFR1 levels were associated and explained 24% of the variability of motor composite scores (p=0.003). Plasma levels of sTNFR1 were associated with the increase in cognitive and motor development scores in infants between 6 and 24 months of age through a mechanism not directly related to excess body weight. Moreover, increase in plasma levels of leptin reduced the cognitive development in this age range. Copyright © 2017 Elsevier B.V. All rights reserved.
The role of sensorimotor processes in social group contagion.
Cracco, Emiel; Brass, Marcel
2018-06-01
Although it is well known that action observation triggers an imitative response, not much is known about how these responses develop as a function of group size. Research on social contagion suggests that imitative tendencies initially increase but then stabilize as groups become larger. However, these findings have mainly been explained in terms of interpretative processes. Across seven experiments (N = 322), the current study investigated the contribution of sensorimotor processes to social group contagion by looking at the relation between group size and automatic imitation in a task that involved minimal interpretation. The results of Experiments 1-2 revealed that automatic imitation increased with group size according to an asymptotic curve on congruent trials but a linear curve on incongruent trials. The results of Experiments 3-7 showed that the asymptote on congruent trials disappeared when no control was needed, namely in the absence of incongruent trials. This suggests that the asymptote in the relation between group size and automatic imitation can be explained in terms of strategic control mechanisms that aim to prevent unintended imitative responses. The findings of the current study are in close correspondence with previous research in the social domain and as such support the hypothesis that sensorimotor processes contribute to the relation between group size and social contagion. Copyright © 2018 Elsevier Inc. All rights reserved.
Afschrift, Maarten; De Groote, Friedl; Verschueren, Sabine; Jonkers, Ilse
2018-01-01
The response to stance perturbations changes with age. The shift from an ankle to a hip strategy with increasing perturbation magnitude occurs at lower accelerations in older than in young adults. This strategy shift has been related to age-related changes in muscle and sensory function. However, the effect of isolated changes in muscle or sensory function on the responses following stance perturbations cannot be determined experimentally since changes in muscle and sensory function occur simultaneously. Therefore, we used predictive simulations to estimate the effect of isolated changes in (rates of change in) maximal joint torques, functional base of support, and sensory noise on the response to backward platform translations. To evaluate whether these modeled changes in muscle and sensory function could explain the observed changes in strategy; simulated postural responses with a torque-driven double inverted pendulum model controlled using optimal state feedback were compared to measured postural responses in ten healthy young and ten healthy older adults. The experimentally observed peak hip angle during the response was significantly larger (5°) and the functional base of support was smaller (0.04m) in the older than in the young adults but peak joint torques and rates of joint torque were similar during the recovery. The addition of noise to the sensed states in the predictive simulations could explain the observed increase in peak hip angle in the elderly, whereas changes in muscle function could not. Hence, our results suggest that strength training alone might be insufficient to improve postural control in elderly. Copyright © 2017 Elsevier B.V. All rights reserved.
Chandon, Pierre; Ordabayeva, Nailya
2017-02-01
Five studies show that people, including experts such as professional chefs, estimate quantity decreases more accurately than quantity increases. We argue that this asymmetry occurs because physical quantities cannot be negative. Consequently, there is a natural lower bound (zero) when estimating decreasing quantities but no upper bound when estimating increasing quantities, which can theoretically grow to infinity. As a result, the "accuracy of less" disappears (a) when a numerical or a natural upper bound is present when estimating quantity increases, or (b) when people are asked to estimate the (unbounded) ratio of change from 1 size to another for both increasing and decreasing quantities. Ruling out explanations related to loss aversion, symbolic number mapping, and the visual arrangement of the stimuli, we show that the "accuracy of less" influences choice and demonstrate its robustness in a meta-analysis that includes previously published results. Finally, we discuss how the "accuracy of less" may explain asymmetric reactions to the supersizing and downsizing of food portions, some instances of the endowment effect, and asymmetries in the perception of increases and decreases in physical and psychological distance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Patriarchy, family structure and the exploitation of women's labor.
Heath, J A; Ciscel, D H
1988-09-01
The authors present a case for including the patriarchal model into the analysis of female labor force participation in the United States. They argue that only if it is assumed that the division of labor and distribution of goods and services are structured to benefit the male head of the family can various trends be explained, including the low relative income of women compared to men, the increase in female labor force participation without a corresponding increase in household work by men, and the increasing number of divorces initiated by women despite the fact that divorce increases female poverty.
Ruiz-Muñoz, Maria; González-Sánchez, Manuel; Martín-Martín, Jaime; Cuesta-Vargas, Antonio I
2017-06-01
To analyse the torque variation level that could be explained by the muscle activation (EMG) amplitude of the three major foot dorsiflexor muscles (tibialis anterior (TA), extensor digitorum longus (EDL), extensor hallucis longus (EHL)) during isometric foot dorsiflexion at different intensities. In a cross-sectional study, forty-one subjects performed foot dorsiflexion at 100%, 75%, 50% and 25% of maximal voluntary contractions (MVC) with the hip and knee flexed 90° and the ankle in neutral position (90° between leg and foot). Three foot dorsiflexions were performed for each intensity. Outcome variables were: maximum (100% MVC) and relative torque (75%, 50%, 25% MVC), maximum and relative EMG amplitude. A linear regression analysis was calculated for each intensity of the isometric foot dorsiflexion. The degree of torque variation (dependent variable) from the independent variables explain (EMG amplitude of the three major foot dorsiflexor muscles) the increases when the foot dorsiflexion intensity is increased, with values of R 2 that range from 0.194 (during 25% MVC) to 0.753 (during 100% MVC). The reliability of the outcome variables was excellent. The EMG amplitude of the three main foot dorsiflexors exhibited more variance in the dependent variable (torque) when foot dorsiflexion intensity increases. Copyright © 2016 Elsevier Ltd. All rights reserved.
Impact of the EURO-2016 football cup on emergency department visits related to alcohol and injury.
Noel, G N; Roch, A R; Michelet, P M; Boiron, L B; Gentile, S G; Viudes, G V
2018-06-01
In Marseille, the 2016 EURO football cup days were independently associated with a 43% increase in alcohol-related visits in the Emergency Department (ED). Patients admitted for alcohol consumption were younger (41 vs. 46.6; P < 0.001), more often male (82.8% vs. 60.1%; P < 0.001) and more often admitted as inpatients (24.0% vs. 16.5%; P = 0.03) than those admitted for injury. Unlike reported in previous studies, injury-related visits did not increase. This could be explained by coding practice variability between EDs (alcohol or injury). To account for this variability, both diagnosis groups must be separately included when using ED data for preparing and monitoring major gatherings.
A new look at children's understanding of mind and emotion: the case of prayer.
Bamford, Christi; Lagattuta, Kristin Hansen
2010-01-01
Multiple methods were used to examine children's awareness of connections between emotion and prayer. Four-, 6-, and 8-year-olds and adults (N = 100) predicted whether people would pray when feeling different emotions, explained why characters in different situations decided to pray, and predicted whether characters' emotions would change after praying. Four- and 6-year-olds exclusively judged that positive emotions motivate prayer, whereas 8-year-olds and adults most often predicted that negative emotions would cause people to pray and that praying could improve emotions. There was also a significant increase between 4 and 8 years in explaining prayer as motivated by need for assistance, for thanksgiving, and for conversation, as well as for explaining postprayer emotions in relation to God or prayer. Religious background predicted individual differences in reasoning only for 4-year-olds. Copyright 2009 APA, all rights reserved.
The Curse of Expertise: When More Knowledge Leads to Miscalibrated Explanatory Insight.
Fisher, Matthew; Keil, Frank C
2016-07-01
Does expertise within a domain of knowledge predict accurate self-assessment of the ability to explain topics in that domain? We find that expertise increases confidence in the ability to explain a wide variety of phenomena. However, this confidence is unwarranted; after actually offering full explanations, people are surprised by the limitations in their understanding. For passive expertise (familiar topics), miscalibration is moderated by education; those with more education are accurate in their self-assessments (Experiment 1). But when those with more education consider topics related to their area of concentrated study (college major), they also display an illusion of understanding (Experiment 2). This "curse of expertise" is explained by a failure to recognize the amount of detailed information that had been forgotten (Experiment 3). While expertise can sometimes lead to accurate self-knowledge, it can also create illusions of competence. Copyright © 2015 Cognitive Science Society, Inc.
Poggel, Dorothe A; Treutwein, Bernhard; Calmanti, Claudia; Strasburger, Hans
2012-08-01
Temporal performance parameters vary across the visual field. Their topographical distributions relative to each other and relative to basic visual performance measures and their relative change over the life span are unknown. Our goal was to characterize the topography and age-related change of temporal performance. We acquired visual field maps in 95 healthy participants (age: 10-90 years): perimetric thresholds, double-pulse resolution (DPR), reaction times (RTs), and letter contrast thresholds. DPR and perimetric thresholds increased with eccentricity and age; the periphery showed a more pronounced age-related increase than the center. RT increased only slightly and uniformly with eccentricity. It remained almost constant up to the age of 60, a marked change occurring only above 80. Overall, age was a poor predictor of functionality. Performance decline could be explained only in part by the aging of the retina and optic media. In Part II, we therefore examine higher visual and cognitive functions.
No association between telomere length-related loci and number of cutaneous nevi.
Li, Xin; Liang, Geyu; Du, Mengmeng; De Vivo, Immaculata; Nan, Hongmei
2016-12-13
Longer telomeres have been associated both with increased melanoma risk and increased nevus counts. Nevus count is one of the strongest risk factors for melanoma. Recent data showed that a genetic score derived by telomere length-related single nucleotide polymorphisms (SNPs) was strongly associated with melanoma risk; however, the relationships between these SNPs and number of cutaneous nevi have not been investigated. We evaluated the associations between telomere length-related SNPs reported by previous genome-wide association study (GWAS) and nevus counts among 15,955 participants of European Ancestry in the Nurses' Health Study and Health Professionals Follow-up Study. None of the SNPs was associated with nevus counts, nor was the genetic score combining the dosage of alleles related to increased telomere length. The telomere length-related SNPs identified by published GWAS do not appear to play an important role in nevus formation. Genetic determinants of telomere length reported by GWAS do not explain the observed epidemiologic association between telomere length and nevus counts.
Emigration for Higher Education: The Case of Palestinians Living in Israel Studying in Jordan
ERIC Educational Resources Information Center
Arar, Khalid; Haj-Yehia, Kussai
2010-01-01
This study explored reasons for the rapid increase in the number of Palestinian Arabs from Israel (PAI) studying higher education (HE) in Jordan. Four hundred and sixty PAI studying in Jordan answered a questionnaire assessing factors related to HE in both countries. Lenient admission requirements and cultural-language similarity explain Jordan's…
Hitting Is Contagious: Experience and Action Induction
ERIC Educational Resources Information Center
Gray, Rob; Beilock, Sian L.
2011-01-01
In baseball, it is believed that "hitting is contagious," that is, probability of success increases if the previous few batters get a hit. Could this effect be partially explained by action induction--that is, the tendency to perform an action related to one that has just been observed? A simulation was used to investigate the effect of inducing…
Dissociable Contributions of Imagination and Willpower to the Malleability of Human Patience.
Jenkins, Adrianna C; Hsu, Ming
2017-07-01
The ability to exercise patience is important for human functioning. Although it is known that patience can be promoted by using top-down control, or willpower, to override impatient impulses, patience is also malleable-in particular, susceptible to framing effects-in ways that are difficult to explain using willpower alone. So far, the mechanisms underlying framing effects on patience have been elusive. We investigated the role of imagination in these effects. In a behavioral experiment (Experiment 1), a classic framing manipulation (sequence framing) increased self-reported and independently coded imagination during intertemporal choice. In an investigation of neural responses during decision making (Experiment 2), sequence framing increased the extent to which patience was related to activation in brain regions associated with imagination, relative to activation in regions associated with willpower, and increased functional connectivity of brain regions associated with imagination, but not willpower, relative to regions associated with valuation. Our results suggest that sequence framing can increase the role of imagination in decision making without increasing the exertion of willpower.
Family Structure and the Intergenerational Transmission of Educational Advantage*
Martin, Molly A.
2013-01-01
I examine whether the effect of parents’ education on children’s educational achievement and attainment varies by family structure and, if so, whether this can be explained by differential parenting practices. Using data from the National Education Longitudinal Study of 1988, I find that as parents’ education increases, children in single mother families experience a lower boost in their achievement test scores, likelihood of attending any post-secondary schooling, likelihood of completing a four-year college degree, and years of completed schooling relative to children living with both biological parents. Differences in parents’ educational expectations, intergenerational closure, and children’s involvement in structured leisure activities partially explain these status transmission differences by family structure. The findings imply that, among children with highly educated parents, children of single mothers are less likely to be highly educated themselves relative to children who grow up with both biological parents. PMID:23017695
[Emigration of Quebec physicians: motivation for departure and return].
Leduc, N; Bilodeau, H; Contandriopoulos, A P; Sainte-Marie, G; Fournier, M A; Dandavino, A
2001-01-01
Since the 80's, outmigration of physicians from Quebec is steadily increasing. About 46 percent of outmigrating doctors explain their move by factors related to their occupational life (higher income, greater opportunity in the academic career, larger amount of resources devoted to the health care system). Nearly 40 percent relate their decision to personal factors (greater job opportunity for their wife/husband, quality of family life...). The factors linked to the context of the receiving place (political climate, linguistic regulations, income tax level...) play a minor role on the migration decision. As concerns the returning physicians, 80 percent explain their decision by personal factors. The factors linked to the occupational life have a lower role. It appears therefore that doctor outmigration from Quebec is not directly determined by manpower policies adopted by the Province during the last two decades, except the policies directly linked to the income level of professionals.
Different pathways explain alcohol related problems in female and male college students
Pedrelli, P.; Collado, A.; Shapero, B. G.; Brill, C.; MacPherson, L.
2016-01-01
Objectives Comprehensive models elucidating the intricate associations of depressive symptoms, coping motives, alcohol use, alcohol-related problems (ARP) and gender among young adults have been scarcely examined. This study investigated relationships among these variables and the effect of gender on these pathways. Methods College students (N = 163; 49.7% female) completed self-report measures on alcohol consumption, depressive symptoms, coping motives, and ARPs. Results Structural equation modeling showed that the association between depressive symptoms and ARPs was mediated by coping motives in both females and males. However, frequency of heavy alcohol use mediated the association between depressive symptoms and ARPs in females but not in males. Conclusions Different models explain the association between depressive symptoms and ARPs in male and female college students. Prevention programs aimed at reducing ARPs should focus on increasing alcohol screening among students with depressive symptoms, teaching coping skills, and emphasizing moderation in alcohol consumption. PMID:27219280
Mentalizing mediates the relationship between psychopathy and type of aggression in schizophrenia.
Bo, Sune; Abu-Akel, Ahmad; Kongerslev, Mickey; Haahr, Ulrik Helt; Bateman, Anthony
2014-01-01
Convincing evidence demonstrates that psychopathy is associated with premeditated aggression. However, studies have failed to explain why this association exists and whether socio-cognitive functions, such as mentalizing, could explain the relation. This cross-sectional study investigates, in 108 patients with schizophrenia, the association of psychopathy and mentalizing abilities with premeditated and impulsive aggression and probes the nature of their influence on these specific aggression patterns. Patients' engagement in premeditated aggression was associated with diminishing mentalizing and increasing psychopathic tendencies. Moreover, mediation analyses reveal that the ability to attribute mental states to others mediates the relation between psychopathy and type of aggression. This mediation is facilitated by a specific mentalizing profile characterized by the presence of intact cognitive and deficient emotional mentalizing capacities. This study is the first to report a mediating effect of mentalizing on the relationship between psychopathy and type of aggression in schizophrenia. Implications of these results are discussed.
NASA Astrophysics Data System (ADS)
Deng, J.; Lee, K. K. M.
2017-12-01
At nearly 2900 km depth, the core-mantle boundary (CMB) represents the largest density increase within the Earth going from a rocky mantle into an iron-alloy core. This compositional change sets up steep temperature gradients, which in turn influences mantle flow, structure and seismic velocities. Here we compute the melting phase relations of (Mg,Fe)O ferropericlase, the second most abundant mineral in the Earth's mantle, at CMB conditions and find that ultralow-velocity zones (ULVZs) could be explained by solid ferropericlase with 35 < Mg# = 100×(Mg/(Mg+Fe) by mol%) < 65. For compositions outside of this range, a solid ferropericlase cannot explain ULVZs. Additionally, solid ferropericlase can also provide a matrix for iron infiltration at the CMB by morphological instability, providing a mechanism for a high electrical conductivity layer of appropriate length scale inferred from core nutations.
Family structure and the intergenerational transmission of educational advantage.
Martin, Molly A
2012-01-01
I examine whether the effect of parents' education on children's educational achievement and attainment varies by family structure and, if so, whether this can be explained by differential parenting practices. Using data from the National Education Longitudinal Study of 1988, I find that as parents' education increases, children in single mother families experience a lower boost in their achievement test scores, likelihood of attending any post-secondary schooling, likelihood of completing a 4-year college degree, and years of completed schooling relative to children living with both biological parents. Differences in parents' educational expectations, intergenerational closure, and children's involvement in structured leisure activities partially explain these status transmission differences by family structure. The findings imply that, among children with highly educated parents, children of single mothers are less likely to be highly educated themselves relative to children who grow up with both biological parents. Copyright © 2011 Elsevier Inc. All rights reserved.
Tack, Ayco J. M.; Mononen, Tommi; Hanski, Ilkka
2015-01-01
Climate change is known to shift species' geographical ranges, phenologies and abundances, but less is known about other population dynamic consequences. Here, we analyse spatio-temporal dynamics of the Glanville fritillary butterfly (Melitaea cinxia) in a network of 4000 dry meadows during 21 years. The results demonstrate two strong, related patterns: the amplitude of year-to-year fluctuations in the size of the metapopulation as a whole has increased, though there is no long-term trend in average abundance; and there is a highly significant increase in the level of spatial synchrony in population dynamics. The increased synchrony cannot be explained by increasing within-year spatial correlation in precipitation, the key environmental driver of population change, or in per capita growth rate. On the other hand, the frequency of drought during a critical life-history stage (early larval instars) has increased over the years, which is sufficient to explain the increasing amplitude and the expanding spatial synchrony in metapopulation dynamics. Increased spatial synchrony has the general effect of reducing long-term metapopulation viability even if there is no change in average metapopulation size. This study demonstrates how temporal changes in weather conditions can lead to striking changes in spatio-temporal population dynamics. PMID:25854888
Giant photocurrent enhancement by transition metal doping in quantum dot sensitized solar cells
NASA Astrophysics Data System (ADS)
Rimal, Gaurab; Pimachev, Artem K.; Yost, Andrew J.; Poudyal, Uma; Maloney, Scott; Wang, Wenyong; Chien, TeYu; Dahnovsky, Yuri; Tang, Jinke
2016-09-01
A huge enhancement in the incident photon-to-current efficiency of PbS quantum dot (QD) sensitized solar cells by manganese doping is observed. In the presence of Mn dopants with relatively small concentration (4 at. %), the photoelectric current increases by an average of 300% (up to 700%). This effect cannot be explained by the light absorption mechanism because both the experimental and theoretical absorption spectra demonstrate several times decreases in the absorption coefficient. To explain such dramatic increase in the photocurrent we propose the electron tunneling mechanism from the LUMO of the QD excited state to the Zn2SnO4 (ZTO) semiconductor photoanode. This change is due to the presence of the Mn instead of Pb atom at the QD/ZTO interface. The ab initio calculations confirm this mechanism. This work proposes an alternative route for a significant improvement of the efficiency for quantum dot sensitized solar cells.
Adsorption of goethite onto quartz and kaolinite
Goldberg, M.C.; Weiner, Eugene R.; Boymel, P.M.
1984-01-01
The adsorption of colloidal goethite onto quartz and kaolinite substrates has been studied as a function of pH and NaCl concentration. Goethite adsorption was measured quantitatively by Fourier-transform infrared spectroscopy. The results indicate that adsorption onto both substrates is due primarily to coulombic forces; however, the pH dependence of adsorption is very different for the two substrates. This is explained by the fact that the surface charge on quartz is entirely pH-dependent, while kaolinite has surface faces which carry a permanent negative charge. Adsorption of goethite on to kaolinite increases markedly with increasing NaCl concentration, while adsorption onto quartz is relatively independent of NaCl concentration. This can be explained by the influence of NaCl concentration upon the development of surface charge on the substrates. A method is described for separating surface-bound goethite from free goethite.
Skoog, Jessica; Midlöv, Patrik; Borgquist, Lars; Sundquist, Jan; Halling, Anders
2014-04-08
It has been reported that there is a difference in drug prescription between males and females. Even after adjustment for multi-morbidity, females tend to use more prescription drugs compared to males. In this study, we wanted to analyse whether the gender difference in drug treatment could be explained by gender-related morbidity. Data was collected on all individuals 20 years and older in the county of Östergötland in Sweden. The Johns Hopkins ACG Case-Mix System was used to calculate individual level of multi-morbidity. A report from the Swedish National Institute of Public Health using the WHO term DALY was the basis for gender-related morbidity. Prescription drugs used to treat diseases that mainly affect females were excluded from the analyses. The odds of having prescription drugs for males, compared to females, increased from 0.45 (95% confidence interval (CI) 0.44-0.46) to 0.82 (95% CI 0.81-0.83) after exclusion of prescription drugs that are used to treat diseases that mainly affect females. Gender-related morbidity and the use of anti-conception drugs may explain a large part of the difference in prescription drug use between males and females but still there remains a difference between the genders at 18%. This implicates that it is of importance to take the gender-related morbidity into consideration, and to exclude anti-conception drugs, when performing studies regarding difference in drug use between the genders.
Winters, Eric R; Petosa, Rick L; Charlton, Thomas E
2003-06-01
To examine whether knowledge of high school students' actions of self-regulation, and perceptions of self-efficacy to overcome exercise barriers, social situation, and outcome expectation will predict non-school related moderate and vigorous physical exercise. High school students enrolled in introductory Physical Education courses completed questionnaires that targeted selected Social Cognitive Theory variables. They also self-reported their typical "leisure-time" exercise participation using a standardized questionnaire. Bivariate correlation statistic and hierarchical regression were conducted on reports of moderate and vigorous exercise frequency. Each predictor variable was significantly associated with measures of moderate and vigorous exercise frequency. All predictor variables were significant in the final regression model used to explain vigorous exercise. After controlling for the effects of gender, the psychosocial variables explained 29% of variance in vigorous exercise frequency. Three of four predictor variables were significant in the final regression equation used to explain moderate exercise. The final regression equation accounted for 11% of variance in moderate exercise frequency. Professionals who attempt to increase the prevalence of physical exercise through educational methods should focus on the psychosocial variables utilized in this study.
Frick, Andrea; Möhring, Wenke
2016-01-01
Recent research has shown close links between spatial and mathematical thinking and between spatial abilities and motor skills. However, longitudinal research examining the relations between motor, spatial, and mathematical skills is rare, and the nature of these relations remains unclear. The present study thus investigated the relation between children’s motor control and their spatial and proportional reasoning. We measured 6-year-olds’ spatial scaling (i.e., the ability to reason about different-sized spaces), their mental transformation skills, and their ability to balance on one leg as an index for motor control. One year later (N = 126), we tested the same children’s understanding of proportions. We also assessed several control variables (verbal IQ and socio-economic status) as well as inhibitory control, visuo-spatial and verbal working memory. Stepwise hierarchical regressions showed that, after accounting for effects of control variables, children’s balance skills significantly increased the explained variance in their spatial performance and proportional reasoning. Our results suggest specific relations between balance skills and spatial as well as proportional reasoning skills that cannot be explained by general differences in executive functioning or intelligence. PMID:26793157
EXPLAINING THE ASSOCIATION BETWEEN INCARCERATION AND DIVORCE*
Siennick, Sonja E.; Stewart, Eric A.; Staff, Jeremy
2014-01-01
Recent studies have suggested that incarceration dramatically increases the odds of divorce, but we know little about the mechanisms that explain the association. This study uses prospective longitudinal data from a subset of married young adults in the National Longitudinal Study of Adolescent Health (N = 1,919) to examine whether incarceration is associated with divorce indirectly via low marital love, economic strain, relationship violence, and extramarital sex. The findings confirmed that incarcerations occurring during, but not before, a marriage were associated with an increased hazard of divorce. Incarcerations occurring during marriage also were associated with less marital love, more relationship violence, more economic strain, and greater odds of extramarital sex. Above-average levels of economic strain were visible among respondents observed preincarceration, but only respondents observed postincarceration showed less marital love, more relationship violence, and higher odds of extramarital sex than did respondents who were not incarcerated during marriage. These relationship problems explained approximately 40 percent of the association between incarceration and marital dissolution. These findings are consistent with theoretical predictions that a spouse’s incarceration alters the rewards and costs of the marriage and the relative attractiveness of alternative partners. PMID:25598544
Danielsen, Charlotte; Hansen, Lise Stengård; Nachman, Gösta; Herling, Christian
2004-01-01
Laboratory experiments with Lepidoglyphus destructor on a diet of mainly whole wheat were conducted to study the mite's development and production of a specific allergen, Lep d 2, at four different temperatures (5, 10, 15 and 20 degrees C) and three levels of relative humidity (ca. 70-88%). Statistical models were used to analyse the role played by temperature, relative humidity and time in explaining the observed number of L. destructor and the amount of allergen produced. Moreover, the life stage distributions of the mites were determined and related to the population growth. Based on a statistical model the intrinsic rate of natural increase, rm, was computed for a range of different temperatures and relative humidities. High relative humidity in combination with temperatures at about 25 degrees C will lead to the highest rm (ca. 0.15 day-1). The highest concentration of Lep d 2 was 3 micrograms g-1 grain, found at 20 degrees C and high relative humidity at a mite density of 254 mites g-1 grain. The concentration of allergens in the grain was best explained by a model that incorporated both the current and the cumulative numbers of mites.
Sheikh, Mashhood A.; Abelsen, Birgit; Olsen, Jan A.
2016-01-01
Previous studies have shown that socio-demographic factors, childhood socioeconomic status (CSES), childhood traumatic experiences (CTEs), social support and behavioral factors are associated with health and well-being in adulthood. However, the relative importance of these factors for mental health, health, and well-being has not been studied. Moreover, the mechanisms by which CTEs affect mental health, health, and well-being in adulthood are not clear. Using data from a representative sample (n = 12,981) of the adult population in Tromsø, Norway, this study examines (i) the relative contribution of structural conditions (gender, age, CSES, psychological abuse, physical abuse, and substance abuse distress) to social support and behavioral factors in adulthood; (ii) the relative contribution of socio-demographic factors, CSES, CTEs, social support, and behavioral factors to three multi-item instruments of mental health (SCL-10), health (EQ-5D), and subjective well-being (SWLS) in adulthood; (iii) the impact of CTEs on mental health, health, and well-being in adulthood, and; (iv) the mediating role of adult social support and behavioral factors in these associations. Instrumental support (24.16%, p < 0.001) explained most of the variation in mental health, while gender (21.32%, p < 0.001) explained most of the variation in health, and emotional support (23.34%, p < 0.001) explained most of the variation in well-being. Psychological abuse was relatively more important for mental health (12.13%), health (7.01%), and well-being (9.09%), as compared to physical abuse, and substance abuse distress. The subjective assessment of childhood financial conditions was relatively more important for mental health (6.02%), health (10.60%), and well-being (20.60%), as compared to mother's and father's education. CTEs were relatively more important for mental health, while, CSES was relatively more important for health and well-being. Respondents exposed to all three types of CTEs had a more than two-fold increased risk of being mentally unhealthy (RRTotal Effect = 2.75, 95% CI: 2.19–3.10), an 89% increased risk of being unhealthy (RRTotal Effect = 1.89, 95% CI: 1.47–1.99), and a 42% increased risk of having a low level of well-being in adulthood (RRTotal Effect = 1.42, 95% CI: 1.29–1.52). Social support and behavioral factors mediate 11–18% (p < 0.01) of these effects. The study advances the theoretical understanding of how CTEs influence adult mental health, health, and well-being. PMID:27252668
Bunnell, David B.; Hale, R. Scott; Vanni, Michael J.; Stein, Roy A.
2006-01-01
Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Ohio reservoirs and larvae from 9 reservoirs during 1998-2001. We sampled chlorophyll as an index of reservoir productivity and obtained daily estimates of water elevation to determine the impact of hydrology on recruitment. Akaike's information criterion (AIC) revealed that Ricker and Beverton-Holt stock-recruit models that included chlorophyll best explained the variation in larval density and age-2 recruits. Specifically, spawning stock catch per effort (CPE) and chlorophyll explained 63-64% of the variation in larval density. In turn, larval density and chlorophyll explained 43-49% of the variation in age-2 recruit CPE. Finally, spawning stock CPE and chlorophyll were the best predictors of recruit CPE (i.e., 74-86%). Although larval density and recruitment increased with chlorophyll, neither was related to seasonal water elevation. Also, the AIC generally did not distinguish between Ricker and Beverton-Holt models. From these relationships, we concluded that crappie recruitment can be limited by spawning stock CPE and larval production when spawning stock sizes are low (i.e., CPE , 5 crappies/net-night). At higher levels of spawning stock sizes, spawning stock CPE and recruitment were less clearly related. To predict recruitment in Ohio reservoirs, managers should assess spawning stock CPE with trap nets and estimate chlorophyll concentrations. To increase crappie recruitment in reservoirs where recruitment is consistently poor, managers should use regulations to increase spawning stock size, which, in turn, should increase larval production and recruits to the fishery.
Electrochromatographic retention of peptides on strong cation-exchange stationary phases.
Nischang, Ivo; Höltzel, Alexandra; Tallarek, Ulrich
2010-03-01
We analyze the systematic and substantial electrical field-dependence of electrochromatographic retention for four counterionic peptides ([Met5]enkephalin, oxytocin, [Arg8]vasopressin, and luteinizing hormone releasing hormone (LHRH) ) on a strong cation-exchange (SCX) stationary phase. Our experiments show that retention behavior in the studied system depends on the charge-selectivity of the stationary phase particles, the applied voltage, and the peptides' net charge. Retention factors of twice positively charged peptides ([Arg8]vasopressin and LHRH at pH 2.7) decrease with increasing applied voltage, whereas lower charged peptides (oxytocin and [Met5]enkephalin at pH 2.7, [Arg8]vasopressin and LHRH at pH 7.0) show a concomitant increase in their retention factors. The observed behavior is explained on the basis of electrical field-induced concentration polarization (CP) that develops around the SCX particles of the packing. The intraparticle concentration of charged species (buffer ions, peptides) increases with increasing applied voltage due to diffusive backflux from the enriched CP zone associated with each SCX particle. For twice charged and on the SCX phase strongly retained peptides the local increase in mobile phase ionic strength reduces the electrostatic interactions with the stationary phase, which explains the decrease of retention factors with increasing applied voltage and CP intensity. Lower charged and weaker retained peptides experience a much stronger relative intraparticle enrichment than the twice-charged peptides, which results in a net increase of retention factors with increasing applied voltage. The CP-related contribution to electrochromatographic retention of peptides on the SCX stationary phase is modulated by the applied voltage, the mobile phase ionic strength, and the peptides' net charge and could be used for selectivity tuning in difficult separations.
Sbihi, Hind; Brook, Jeffrey R; Allen, Ryan W; Curran, Jason H; Dell, Sharon; Mandhane, Piush; Scott, James A; Sears, Malcolm R; Subbarao, Padmaja; Takaro, Timothy K; Turvey, Stuart E; Wheeler, Amanda J; Brauer, Michael
2013-06-19
Exposure to traffic-related air pollution (TRAP) can adversely impact health but epidemiologic studies are limited in their abilities to assess long-term exposures and incorporate variability in indoor pollutant infiltration. In order to examine settled house dust levels of hopanes, engine lubricating oil byproducts found in vehicle exhaust, as a novel TRAP exposure measure, dust samples were collected from 171 homes in five Canadian cities and analyzed by gas chromatography-mass spectrometry. To evaluate source contributions, the relative abundance of the highest concentration hopane monomer in house dust was compared to that in outdoor air. Geographic variables related to TRAP emissions and outdoor NO2 concentrations from city-specific TRAP land use regression (LUR) models were calculated at each georeferenced residence location and assessed as predictors of variability in dust hopanes. Hopanes relative abundance in house dust and ambient air were significantly correlated (Pearson's r=0.48, p<0.05), suggesting that dust hopanes likely result from traffic emissions. The proportion of variance in dust hopanes concentrations explained by LUR NO2 was less than 10% in Vancouver, Winnipeg and Toronto while the correlations in Edmonton and Windsor explained 20 to 40% of the variance. Modeling with household factors such as air conditioning and shoe removal along with geographic predictors related to TRAP generally increased the proportion of explained variability (10-80%) in measured indoor hopanes dust levels. Hopanes can consistently be detected in house dust and may be a useful tracer of TRAP exposure if determinants of their spatiotemporal variability are well-characterized, and when home-specific factors are considered.
2013-01-01
Background Exposure to traffic-related air pollution (TRAP) can adversely impact health but epidemiologic studies are limited in their abilities to assess long-term exposures and incorporate variability in indoor pollutant infiltration. Methods In order to examine settled house dust levels of hopanes, engine lubricating oil byproducts found in vehicle exhaust, as a novel TRAP exposure measure, dust samples were collected from 171 homes in five Canadian cities and analyzed by gas chromatography–mass spectrometry. To evaluate source contributions, the relative abundance of the highest concentration hopane monomer in house dust was compared to that in outdoor air. Geographic variables related to TRAP emissions and outdoor NO2 concentrations from city-specific TRAP land use regression (LUR) models were calculated at each georeferenced residence location and assessed as predictors of variability in dust hopanes. Results Hopanes relative abundance in house dust and ambient air were significantly correlated (Pearson’s r=0.48, p<0.05), suggesting that dust hopanes likely result from traffic emissions. The proportion of variance in dust hopanes concentrations explained by LUR NO2 was less than 10% in Vancouver, Winnipeg and Toronto while the correlations in Edmonton and Windsor explained 20 to 40% of the variance. Modeling with household factors such as air conditioning and shoe removal along with geographic predictors related to TRAP generally increased the proportion of explained variability (10-80%) in measured indoor hopanes dust levels. Conclusions Hopanes can consistently be detected in house dust and may be a useful tracer of TRAP exposure if determinants of their spatiotemporal variability are well-characterized, and when home-specific factors are considered. PMID:23782977
NASA Astrophysics Data System (ADS)
Okayama, Hiroshi; Li, Wei
2006-09-01
Atmopheric turbulence is one of the important correction factors to evaluate the earth's surface using a sinsor on a satellite. CO II and aerosol are selected as factors of turbulence. The effects of turbulence caused by CO II and aerosol on the light reflected from the earth's surface are estimated by measuring the degradation of spatial coherence of light in a chamber in which atmospheric turbulence is generated. Dry ice is used to generate carbon dioxide gas. degradation of spatial coherence is measured in relation to the increase of CO II. Turbulence caused by aerosol is measured by density of smoke cigarettes. The spatial coherence of light in the chamber degrades in relation to the increase of aerosol and as a result the turbulence increases. The relation between the turbulence and the degree of spatial coherence is explained in a formula.
ERIC Educational Resources Information Center
Alcock, Lara; Simpson, Adrian
2017-01-01
This paper describes a study in which we investigated relationships between defining mathematical concepts--increasing and decreasing infinite sequences--explaining their meanings and classifying consistently with formal definitions. We explored the effect of defining, explaining or studying a definition on subsequent classification, and the…
2014-02-01
long hours , shift work , relational conflict...reasons for an increase in medication. Such sleep problems were often explained in textual responses to be the result of long work hours , shift work ...to be operational in nature [1]. Specifically, long hours , shift work , organizational and leadership challenges, nature of work , additional
ERIC Educational Resources Information Center
Montoro-Rodriguez, Julian; Kosloski, Karl; Montgomery, Rhonda J. V.
2003-01-01
Purpose: The goal of this study was to evaluate the practice-oriented model of service use (Yeatts, Crow, & Folts, 1992) relative to the more widely used behavioral model (Andersen, 1968) in its ability to explain the use of respite services by caregivers of Alzheimer's patients. Unlike the behavioral model, which focuses primarily on…
ERIC Educational Resources Information Center
Reike, Dennis; Schwarz, Wolf
2016-01-01
The time required to determine the larger of 2 digits decreases with their numerical distance, and, for a given distance, increases with their magnitude (Moyer & Landauer, 1967). One detailed quantitative framework to account for these effects is provided by random walk models. These chronometric models describe how number-related noisy…
Dardis, Christina M; Dixon, Kristiana J; Edwards, Katie M; Turchik, Jessica A
2015-04-01
This article provides a review of the literature on dating violence (DV) perpetration, specifically sex similarities and differences in the correlates and predictors of DV perpetration and the utility of current theories to explain young men's and women's DV perpetration. Overall, many of the correlates and predictors of DV perpetration are similar among young men and women (e.g., witnessing interparental violence, experiencing child abuse, alcohol abuse, traditional gender roles, relationship power dynamics). However, young women's perpetration of DV is more strongly related to internalizing symptoms (e.g., depression), trait anger and hostility, and experiencing DV victimization than young men's perpetration, whereas young men's perpetration of DV is more consistently related to lower socioeconomic status and educational attainment, antisocial personality characteristics, and increased relationship length than young women's perpetration. Each theory offers insights into but does not fully account for the correlates and predictors of DV perpetration. Sociocultural theories may be useful in explaining the use of coercive control in relationships, and learning/intergenerational transmission of violence theories may be useful in explaining bidirectional couple violence. Future research should focus on integrative theories, such as in the social-ecological theory, in order to explain various forms of DV. Our understanding of young men's and young women's DV perpetration is limited by cross-sectional research designs, methodological inconsistencies, a lack of sex-specific analytic approaches, and a lack of focus on contextual factors; more multivariate and longitudinal studies are needed. Further, as DV prevention programming is often presented in mixed-sex formats, a critical understanding of sex differences and similarities in DV perpetration could ultimately refine and improve effectiveness of programming efforts aimed at reducing DV. © The Author(s) 2014.
Mouchet, Maud; Levers, Christian; Zupan, Laure; Kuemmerle, Tobias; Plutzar, Christoph; Erb, Karlheinz; Lavorel, Sandra; Thuiller, Wilfried; Haberl, Helmut
2015-01-01
We compared the effectiveness of environmental variables, and in particular of land-use indicators, to explain species richness patterns across taxonomic groups and biogeographical scales (i.e. overall pan-Europe and ecoregions within pan-Europe). Using boosted regression trees that handle non-linear relationships, we compared the relative influence (as a measure of effectiveness) of environmental variables related to climate, landscape (or habitat heterogeneity), land-use intensity or energy availability to explain European vertebrate species richness (birds, amphibians, and mammals) at the continental and ecoregion scales. We found that dominant land cover and actual evapotranspiration that relate to energy availability were the main correlates of vertebrate species richness over Europe. At the ecoregion scale, we identified four distinct groups of ecoregions where species richness was essentially associated to (i) seasonality of temperature, (ii) actual evapotranspiration and/or mean annual temperature, (iii) seasonality of precipitation, actual evapotranspiration and land cover) and (iv) and an even combination of the environmental variables. This typology of ecoregions remained valid for total vertebrate richness and the three vertebrate groups taken separately. Despite the overwhelming influence of land cover and actual evapotranspiration to explain vertebrate species richness patterns at European scale, the ranking of the main correlates of species richness varied between regions. Interestingly, landscape and land-use indicators did not stand out at the continental scale but their influence greatly increased in southern ecoregions, revealing the long-lasting human footprint on land-use–land-cover changes. Our study provides one of the first multi-scale descriptions of the variability in the ranking of correlates across several taxa. PMID:26161981
Earthquake clouds and physical mechanism of their formation.
NASA Astrophysics Data System (ADS)
Doda, L.; Pulinets, S.
2006-12-01
The Lithosphere-Atmosphere-Ionosphere (LAI) coupling model created recently permitted to explain some unknown phenomena observed around the time of strong earthquakes. One of them is formation of special shape clouds, usually presented as the thin linear structures. It was discovered that these clouds are associated with the active tectonic faults or with the tectonic plate borders. They repeat the fault shape but usually are turned in relation to the fault position. Their formation is explained by the anomalous vertical electric field generated in the vicinity of active tectonic structure due to air ionization produced by the radon increased emanation. The new formed ions through the hydration process do not recombine and growth with time due to increased water molecules attachment to the ion. Simultaneously they move up driven by the anomalous electric field and drift in the crossed ExB fields. At the higher altitudes the large ion clusters become the centers of condensation and the cloud formation. Examples for the recent major earthquakes (Sumatra 2004, Kashmir 2005, Java 2006) are presented. The size and the angle of the cloud rotation in relation to the fault position permit to estimate the magnitude of the impending earthquake.
The thermal mismatch hypothesis explains host susceptibility to an emerging infectious disease.
Cohen, Jeremy M; Venesky, Matthew D; Sauer, Erin L; Civitello, David J; McMahon, Taegan A; Roznik, Elizabeth A; Rohr, Jason R
2017-02-01
Parasites typically have broader thermal limits than hosts, so large performance gaps between pathogens and their cold- and warm-adapted hosts should occur at relatively warm and cold temperatures, respectively. We tested this thermal mismatch hypothesis by quantifying the temperature-dependent susceptibility of cold- and warm-adapted amphibian species to the fungal pathogen Batrachochytrium dendrobatidis (Bd) using laboratory experiments and field prevalence estimates from 15 410 individuals in 598 populations. In both the laboratory and field, we found that the greatest susceptibility of cold- and warm-adapted hosts occurred at relatively warm and cool temperatures, respectively, providing support for the thermal mismatch hypothesis. Our results suggest that as climate change shifts hosts away from their optimal temperatures, the probability of increased host susceptibility to infectious disease might increase, but the effect will depend on the host species and the direction of the climate shift. Our findings help explain the tremendous variation in species responses to Bd across climates and spatial, temporal and species-level variation in disease outbreaks associated with extreme weather events that are becoming more common with climate change. © 2017 John Wiley & Sons Ltd/CNRS.
Relative Food Prices and Obesity in U.S. Metropolitan Areas: 1976-2001
Xu, Xin; Variyam, Jayachandran N.; Zhao, Zhenxiang; Chaloupka, Frank J.
2014-01-01
This study investigates the impact of food price on obesity, by exploring the co-occurrence of obesity growth with relative food price reduction between 1976 and 2001. Analyses control for female labor participation and metropolitan outlet densities that might affect body weight. Both the first-difference and fixed effects approaches provide consistent evidence suggesting that relative food prices have substantial impacts on obesity and such impacts were more pronounced among the low-educated. These findings imply that relative food price reductions during the time period could plausibly explain about 18% of the increase in obesity among the U.S. adults in metropolitan areas. PMID:25502888
Effect of Training Status on Oxygen Consumption in Women After Resistance Exercise.
Benton, Melissa J; Waggener, Green T; Swan, Pamela D
2016-03-01
This study compared acute postexercise oxygen consumption in 11 trained women (age, 46.5 ± 1.6 years; body mass index [BMI], 28.4 ± 1.7 kg·m(-2) and 11 untrained women (age, 46.5 ± 1.5 years; BMI, 27.5 ± 1.5 kg·m(-2)) after resistance exercise (RE). Resistance exercise consisted of 3 sets of 8 exercises (8-12 repetitions at 50-80% 1 repetition maximum). Oxygen consumption (VO2 ml·min(-1)) was measured before and after (0, 20, 40, 60, 90, and 120 minutes) RE. Immediately after cessation of RE (time 0), oxygen consumption increased in both trained and untrained women and remained significantly above baseline through 60 minutes after exercise (p < 0.01). Total oxygen consumption during recovery was 31.3 L in trained women and 27.4 L in untrained women (p = 0.07). In trained women, total oxygen consumption was strongly related to absolute (kg) lean mass (r = 0.88; p < 0.001), relative (kilogram per square meter) lean mass (r = 0.91; p < 0.001), and duration of exercise (r = 0.68; p ≤ 0.05), but in untrained women, only training volume-load was related to total oxygen consumption (r = 0.67; p ≤ 0.05). In trained women, 86% of the variance in oxygen consumption was explained by lean mass and exercise duration, whereas volume-load explained 45% in untrained women. Our findings suggest that, in women, resistance training increases metabolic activity of lean tissue. Postexercise energy costs of RE are determined by the duration of stimulation provided by RE rather than absolute work (volume-load) performed. This phenomenon may be related to type II muscle fibers and increased protein synthesis.
Exercising self-control increases relative left frontal cortical activation
Crowell, Adrienne; Harmon-Jones, Eddie
2016-01-01
Self-control refers to the capacity to override or alter a predominant response tendency. The current experiment tested the hypothesis that exercising self-control temporarily increases approach motivation, as revealed by patterns of electrical activity in the prefrontal cortex. Participants completed a writing task that did vs did not require them to exercise self-control. Then they viewed pictures known to evoke positive, negative or neutral affect. We assessed electroencephalographic (EEG) activity while participants viewed the pictures, and participants reported their trait levels of behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivity at the end of the study. We found that exercising (vs not exercising) self-control increased relative left frontal cortical activity during picture viewing, particularly among individuals with relatively higher BAS than BIS, and particularly during positive picture viewing. A similar but weaker pattern emerged during negative picture viewing. The results suggest that exercising self-control temporarily increases approach motivation, which may help to explain the aftereffects of self-control (i.e. ego depletion). PMID:26341900
Simulating Food Web Dynamics along a Gradient: Quantifying Human Influence
Jordán, Ferenc; Gjata, Nerta; Mei, Shu; Yule, Catherine M.
2012-01-01
Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar) but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1), when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling of eco-dynamics could greatly contribute to understanding various aspects of functional diversity. PMID:22768346
Hartog, Jasper W L; Hummel, Yoran M; Voors, Adriaan A; Schalkwijk, Casper G; Miyata, Toshio; Huisman, Roel M; Smit, Andries J; Van Veldhuisen, Dirk J
2008-09-01
Diastolic dysfunction is a frequent cause of heart failure, particularly in dialysis patients. Advanced glycation end-products (AGEs) are increased in dialysis patients and are suggested to play a role in the development of diastolic dysfunction. The aim of our study was to assess whether AGE accumulation in dialysis patients is related to the presence of diastolic dysfunction. Data were analyzed from 43 dialysis patients, age 58 +/- 15 years, of whom 65% were male. Diastolic function was assessed using tissue velocity imaging (TVI) on echocardiography. Tissue AGE accumulation was measured using a validated skin-autofluorescence (skin-AF) reader. Plasma N(epsilon)-(carboxymethyl)lysine (CML) and N(epsilon)-(carboxyethyl)lysine (CEL) were measured by stable-isotope-dilution tandem mass spectrometry. Plasma pentosidine was measured by high-performance liquid chromatography. Skin-AF correlated with mean E' (r = -0.51, P < .001), E/A ratio (r = -0.39, P = .014), and E/E' (r = 0.38, P = .019). Plasma AGEs were not significantly associated with diastolic function. Multivariable linear regression analysis revealed that 54% of the variance of average E' was explained by age (P = .007), dialysis type (P = 0.016), and skin-AF (P = .013). Tissue AGEs measured as skin-AF, but not plasma AGE levels, were related to diastolic function in dialysis patients. Although this may support the concept that tissue AGEs explain part of the increased prevalence of diastolic dysfunction in these patients, the ambiguous relation between plasma and tissue AGEs needs further exploring.
Burgess, Gregory C; Depue, Brendan E; Ruzic, Luka; Willcutt, Erik G; Du, Yiping P; Banich, Marie T
2010-04-01
Attentional control difficulties in individuals with attention-deficit/hyperactivity disorder (ADHD) might reflect poor working memory (WM) ability, especially because WM ability and attentional control rely on similar brain regions. The current study examined whether WM ability might explain group differences in brain activation between adults with ADHD and normal control subjects during attentional demand. Participants were 20 adults with ADHD combined subtype with no comorbid psychiatric or learning disorders and 23 control subjects similar in age, IQ, and gender. The WM measures were obtained from the Wechsler Adult Intelligence Scale-III and Wechsler Memory Scale-Revised. Brain activation was assessed with functional magnetic resonance imaging (fMRI) while performing a Color-Word Stroop task. Group differences in WM ability explained a portion of the activation in left dorsolateral prefrontal cortex (DLPFC), which has been related to the creation and maintenance of an attentional set for task-relevant information. In addition, greater WM ability predicted increased activation of brain regions related to stimulus-driven attention and response selection processes in the ADHD group but not in the control group. The inability to maintain an appropriate task set in young adults with combined type ADHD, associated with decreased activity in left DLPFC, might in part be due to poor WM ability. Furthermore, in individuals with ADHD, higher WM ability might relate to increased recruitment of stimulus-driven attention and response selection processes, perhaps as a compensatory strategy. Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cornelissen, M.; de Ridder, L.
Radiation doses of 20, 50 or 100 Gy caused the same time related decrease for RNA and proteoglycan (PG) synthesis in embryonic cartilage in vitro (4 days culture). In this paper, participation of lysosomes in this radiation response is investigated. Therefore, we employ a cytochemical method using beta-glycerophosphate as substrate for acid phosphatase (AP) detection. Increase of AP was found 2 days after irradiation and increased during the whole culture period. The increase was more pronounced with a higher radiation dose. Stimulation of AP activity explains the observed radiation response of RNA and PG synthesis.
Weiblen, R Joseph; Florea, Catalin M; Busse, Lynda E; Shaw, L Brandon; Menyuk, Curtis R; Aggarwal, Ishwar D; Sanghera, Jasbinder S
2015-10-15
It has been experimentally observed that moth-eye antireflective microstructures at the end of As2S3 fibers have an increased laser damage threshold relative to thin-film antireflective coatings. In this work, we computationally study the irradiance enhancement in As2S3 moth-eye antireflective microstructures in order to explain the increased damage threshold. We show that the irradiance enhancement occurs mostly on the air side of the interfaces and is minimal in the As2S3 material. We give a physical explanation for this behavior.
Blanco, Luis E; Aragón, Aurora; Lundberg, Ingvar; Lidén, Carola; Wesseling, Catharina; Nise, Gun
2005-01-01
Identification of pesticide exposure determinants has become an issue in explaining exposure variability and improving control measures. Most studies have been conducted in industrialized countries. The aim of this study was to identify relevant dermal exposure determinants among Nicaraguan subsistence farmers. Field data on possible determinants were collected during 32 pesticide applications through observation and supplementary videorecording. A multistep reduction strategy brought down the 110 potential exposure determinants to 27 variables, which were grouped as worksite, spray equipment, working practices, clothing or hygiene practices related. Dermal exposure was quantified with a modification of Fenske's visual scoring method. Multivariate linear regression modeling within groups and across groups was performed. In the within-group analyses, work practices, spray equipment and worksite related determinants explained 52, 33 and 25% of the exposure variability, respectively. Clothing and hygiene practices were weaker determinants and did not always reduce the exposure. The final model included determinants from all groups except hygiene practices and explained 69% of the exposure variability. A less restricted model increased the explained variability to 75%. Several novel determinants were identified, including spraying on a muddy terrain, dew on plants, sealing the tank lid with a cloth and wiping sweat from the face. This study showed that a combination of observation and visual scoring techniques can provide valuable information on determinants of pesticide exposure and affected body parts under developing country conditions. The results could be used to develop job-specific questionnaires and to design training and preventive programs.
Deitz, Mandi F; Williams, Stacey L; Rife, Sean C; Cantrell, Peggy
2015-05-01
The current study investigated a model explaining sexual assault victims' severity of trauma symptoms that incorporated multiple stigma constructs. Integrating the sexual assault literature with the stigma literature, this study sought to better understand trauma-related outcomes of sexual assault by examining three levels of stigma-cultural, social, and self. Results showed self-stigma was significantly and positively related to trauma symptom severity. Thus, results revealed that the internalized aspect of stigma served as a mechanism in the relation between sexual assault severity and increased levels of trauma symptom severity, highlighting the importance of assessing self-stigma in women reporting sexual assault experiences. © The Author(s) 2015.
Implications of Enhanced Relative Humidity in Cold Tropical Cirrus
NASA Technical Reports Server (NTRS)
Jensen, Eric; Pfister, Leonhard
2004-01-01
In situ measurements of water vapor concentration and temperature in tropical cirrus during the CRYSTAL-FACE and Pre-AVE missions indicate that the steady-state relative humidity within cirrus at T less than 200 K is about 20-30% higher than ice saturation. These measurements challenge the conventional belief, that any water vapor in excess of ice saturation should be depleted by crystal growth given sufficient time. Detailed simulations of thin cirrus near the tropopause indicate that this enhanced steady-state relative humidity increases ice number densities, decreases crystal sizes and extends cloud lifetimes. The areal coverage of thin cirrus in the tropics is increased rather than decreased as indicated by simpler conceptual models. Perhaps most significantly, the increased steady-state H2O saturation mixing ratio over ice in thin cirrus near the tropopause results in about a 0.5-1 ppmv increase in the amount of water that can enter the stratosphere across the tropical tropopause cold trap. Hence, the enhanced steady-state relative humidity in cold cirrus implies that lower tropopause temperatures are required to explain the observed stratospheric water vapor mixing ratios than previously assumed.
Oldham, Alana R; Sillett, Stephen C; Tomescu, Alexandru M F; Koch, George W
2010-07-01
Leaves at the tops of most trees are smaller, thicker, and in many other ways different from leaves on the lowermost branches. This height-related variation in leaf structure has been explained as acclimation to differing light environments and, alternatively, as a consequence of hydrostatic, gravitational constraints on turgor pressure that reduce leaf expansion. • To separate hydrostatic effects from those of light availability, we used anatomical analysis of height-paired samples from the inner and outer tree crowns of tall redwoods (Sequoia sempervirens). • Height above the ground correlates much more strongly with leaf anatomy than does light availability. Leaf length, width, and mesophyll porosity all decrease linearly with height and help explain increases in leaf-mass-to-area ratio and decreases in both photosynthetic capacity and internal gas-phase conductance with increasing height. Two functional traits-leaf thickness and transfusion tissue-also increase with height and may improve water-stress tolerance. Transfusion tissue area increases enough that whole-leaf vascular volume does not change significantly with height in most trees. Transfusion tracheids become deformed with height, suggesting they may collapse under water stress and act as a hydraulic buffer that improves leaf water status and reduces the likelihood of xylem dysfunction. • That such variation in leaf structure may be caused more by gravity than by light calls into question use of the terms "sun" and "shade" to describe leaves at the tops and bottoms of tall tree crowns.
Zhang, Jie; Zhao, Xin; Vatner, Dorothy E; McNulty, Tara; Bishop, Sanford; Sun, Zhe; Shen, You-Tang; Chen, Li; Meininger, Gerald A; Vatner, Stephen F
2016-01-01
Objective Increased vascular stiffness is central to the pathophysiology of aging, hypertension, diabetes and atherosclerosis. However, relatively few studies have examined vascular stiffness in both the thoracic and abdominal aorta with aging, despite major differences in anatomy, embryological origin and relation to aortic aneurysm. Approach and Results The two other unique features of this study were 1) to study young (9±1 years) and old (26±1 years) male monkeys, and 2) to study direct and continuous measurements of aortic pressure and thoracic and abdominal aortic diameters in conscious monkeys. As expected, aortic stiffness, β, was increased p<0.05, 2–3 fold, in old vs. young thoracic aorta, and augmented further with superimposition of acute hypertension with phenylephrine. Surprisingly, stiffness was not greater in old thoracic aorta than young abdominal aorta. These results can be explained in part by the collagen/elastin ratio, but more importantly, by disarray of collagen and elastin, which correlated best with vascular stiffness. However, vascular smooth muscle cell stiffness, was not different in thoracic vs. abdominal aorta in either young or old monkeys. Conclusions Thus, aortic stiffness increases with aging as expected, but the most severe increases in aortic stiffness observed in the abdominal aorta is novel, where values in young monkeys equaled, or even exceeded, values of thoracic aortic stiffness in old monkeys. These results can be explained by alterations in collagen/elastin ratio, but even more importantly by collagen and elastin disarray. PMID:26891739
Association of goal orientation with work engagement and burnout in emergency nurses.
Adriaenssens, Jef; De Gucht, Veronique; Maes, Stan
2015-01-01
Goal orientation is a mindset towards the achievement of work-related goals, and it has been found to be related to occupational well-being. This study explored to what extent the 4-dimensional model of goal orientation adds additional variance to the explanation of burnout and work engagement in emergency nurses, after controlling for demographics, job characteristics and organizational variables. Self-report questionnaires including the Leiden Quality of Work Questionnaire for Nurses, Goal Orientation Questionnaire, Maslach Burnout Inventory and Utrecht Work Engagement Scale were completed by 170 out of 274 emergency nurses from 13 secondary Belgian hospitals (response rate 62%). Hierarchical multiple regression analyses were conducted. Goal orientation explained 14 and 13% of the variance in burnout and work engagement respectively. Job control was predictive of both outcomes. Job demands was a predictor of burnout, and social support predicted work engagement. Reward was related to work engagement. The mastery-approach goal orientation was strongly related to an increase in work engagement and to a decrease in burnout. The performance-avoidance goal orientation was strongly related to a decrease in work engagement and to an increase in burnout. The performance-approach and mastery-avoidance goal orientations were not predictive for the two outcome variables. Goal orientation explains additional variance in burnout and work engagement over and above work characteristics and organizational variables. A mastery-approach goal orientation appears to be beneficial while a performance-avoidance goal orientation is not. Hospital management should therefore invest in personal involvement and growth of ER-nurses and in a rewarding organizational culture.
A social cognitive-based model for condom use among college students.
Dilorio, C; Dudley, W N; Soet, J; Watkins, J; Maibach, E
2000-01-01
Social cognitive theory has been used extensively to explain health behaviors. Although the influence of one construct in this model-self-efficacy-has been well established, the role of other social cognitive constructs has not received as much attention in human immunodeficiency virus (HIV) prevention research. More complete understanding of how social cognitive constructs operate together to explain condom use behaviors would be useful in developing HIV and sexually transmitted disease (STD) prevention programs for college students. The primary aim of this study was to test a social cognitive-based model of condom use behaviors among college students. Data were collected from a sample of college students attending six different colleges and universities. Participants were 18 to 25 years of age, single, and sexually active. For the sample of 1,380 participants, the mean age was 20.6 years (SD = 1.76). Most participants reported having had vaginal intercourse (95.8%) and oral sex (86.5%); 16% reported anal sex. Self-efficacy was related directly to condom use behaviors and indirectly through its effect on outcome expectancies. As predicted, self-efficacy was related to anxiety, but anxiety was not related to condom use. Substance use during sexual encounters was related to outcome expectancies but not to condom use as predicted. Overall, the findings lend support to a condom use model based on social cognitive theory and provide implications for HIV interventions. Interventions that focus on self-efficacy are more likely to reduce anxiety related to condom use, increase positive perceptions about condoms, and increase the likelihood of adopting condom use behaviors.
Desire versus Efficacy in Smokers’ Paradoxical Reactions to Pictorial Health Warnings for Cigarettes
Romer, Daniel; Peters, Ellen; Strasser, Andrew A.; Langleben, Daniel
2013-01-01
Pictorial health warnings on cigarette packs create aversive emotional reactions to smoking and induce thoughts about quitting; however, contrary to models of health behavior change, they do not appear to alter intentions to quit smoking. We propose and test a novel model of intention to quit an addictive habit such as smoking (the efficacy-desire model) that can explain this paradoxical effect. At the core of the model is the prediction that self-efficacy and desire to quit an addictive habit are inversely related. We tested the model in an online experiment that randomly exposed smokers (N = 3297) to a cigarette pack with one of three increasing levels of warning intensity. The results supported the model’s prediction that despite the effects of warnings on aversion to smoking, intention to quit smoking is an inverted U-shape function of the smoker’s self-efficacy for quitting. In addition, smokers with greater (lesser) quit efficacy relative to smoking efficacy increase (decrease) intentions to quit. The findings show that previous failures to observe effects of pictorial warning labels on quit intentions can be explained by the contradictory individual differences that warnings produce. Thus, the model explains the paradoxical finding that quit intentions do not change at the population level, even though smokers recognize the implications of warnings. The model suggests that pictorial warnings are effective for smokers with stronger quit-efficacy beliefs and provides guidance for how cigarette warnings and tobacco control strategies can be designed to help smokers quit. PMID:23383006
Ryberg, Karen R.
2017-01-01
Attribution of the causes of trends in nutrient loading is often limited to correlation, qualitative reasoning, or references to the work of others. This paper represents efforts to improve causal attribution of water-quality changes. The Red River of the North basin provides a regional test case because of international interest in the reduction of total phosphorus loads and the availability of long-term total phosphorus data and ancillary geospatial data with the potential to explain changes in water quality over time. The objectives of the study are to investigate structural equation modeling methods for application to water-quality problems and to test causal hypotheses related to the drivers of total phosphorus loads over the period 1970 to 2012. Multiple working hypotheses that explain total phosphorus loads and methods for estimating missing ancillary data were developed, and water-quality related challenges to structural equation modeling (including skewed data and scaling issues) were addressed. The model indicates that increased precipitation in season 1 (November–February) or season 2 (March–June) would increase total phosphorus loads in the basin. The effect of agricultural practices on total phosphorus loads was significant, although the effect is about one-third of the effect of season 1 precipitation. The structural equation model representing loads at six sites in the basin shows that climate and agricultural practices explain almost 60% of the annual total phosphorus load in the Red River of the North basin. The modeling process and the unexplained variance highlight the need for better ancillary long-term data for causal assessments.
Beison, Ashley; Rademacher, David J
2017-03-01
Background and aims Smartphones are ubiquitous. As smartphones increased in popularity, researchers realized that people were becoming dependent on their smartphones. The purpose here was to provide a better understanding of the factors related to problematic smartphone use (PSPU). Methods The participants were 100 undergraduates (25 males, 75 females) whose ages ranged from 18 to 23 (mean age = 20 years). The participants completed questionnaires to assess gender, ethnicity, year in college, father's education level, mother's education level, family income, age, family history of alcoholism, and PSPU. The Family Tree Questionnaire assessed family history of alcoholism. The Mobile Phone Problem Use Scale (MPPUS) and the Adapted Cell Phone Addiction Test (ACPAT) were used to determine the degree of PSPU. Whereas the MPPUS measures tolerance, escape from other problems, withdrawal, craving, and negative life consequences, the ACPAT measures preoccupation (salience), excessive use, neglecting work, anticipation, lack of control, and neglecting social life. Results Family history of alcoholism and father's education level together explained 26% of the variance in the MPPUS scores and 25% of the variance in the ACPAT scores. The inclusion of mother's education level, ethnicity, family income, age, year in college, and gender did not significantly increase the proportion of variance explained for either MPPUS or ACPAT scores. Discussion and conclusions Family history of alcoholism and father's education level are good predictors of PSPU. As 74%-75% of the variance in PSPU scale scores was not explained, future studies should aim to explain this variance.
NASA Astrophysics Data System (ADS)
Lehmann, E.; Hansen, F.; Ulbrich, U.; Nevir, P.; Leckebusch, G. C.
2009-04-01
While most studies on model-projected future climate warming discuss climatological quantities, this study investigates the response of the relative atmospheric angular momentum (AAM) to climate warming for the 21th century and discusses its possible effects on future length-of-day variations. Following the derivation of the dynamic relation between atmosphere and solid earth by Barnes et al. (Proc. Roy. Soc., 1985) this study relates the axial atmospheric excitation function X3 to changes in length-of-day that are proportional to variations in zonal winds. On interannual time scales changes in the relative AAM (ERA40 reanalyses) are well correlated with observed length-of-day (LOD, IERS EOP CO4) variability (r=0.75). The El Niño-Southern Oscillation (ENSO) is a prominent coupled ocean-atmosphere phenomenon to cause global climate variability on interannual time scales. Correspondingly, changes in observed LOD relate to ENSO due to observed strong wind anomalies. This study investigates the varying effect of AAM anomalies on observed LOD by relating AAM to variations to ENSO teleconnections (sea surface temperatures, SSTs) and the Pacific North America (PNA) oscillation for the 20th and 21st century. The differently strong effect of strong El Niño events (explained variance 71%-98%) on present time (1962-2000) observed LOD-AAM relation can be associated to variations in location and strength of jet streams in the upper troposphere. Correspondingly, the relation between AAM and SSTs in the NIÑO 3.4 region also varies between explained variances of 15% to 73%. Recent coupled ocean-atmosphere projections on future climate warming suggest changes in frequency and amplitude of ENSO events. Since changes in the relative AAM indicate shifts in large-scale atmospheric circulation patterns due to climate change, AAM - ENSO relations are assessed in coupled atmosphere-ocean (ECHAM5-OM1) climate warming projections (A1B) for the 21st century. A strong rise (+31%) in relative AAM is observed with major contributions in the upper troposphere where increased jet streams cause large AAM anomalies. Due to increasing westerly winds, an eastward shift can be observed during strong El Niño events for the Pacific and North America centers of the PNA while its southeast center is less pronounced and shifts to the West. As a result, the PNA region during strong 21th century El Niño events is closely located to the PNA region of mean atmospheric conditions of present time. Further analyses on the climate warming scenario (A1B) determined a total of 28 strong El Niño events suggesting a steady increase in ENSO events, magnitude and duration during the last decades of the 21st century. Rising Niño 3.4 SSTs exceed global increases by 15%. Correspondingly to present times, the AAM-SST relation also indicates a range of explained variances from 8% to 82%. Ongoing analyses on 21st century climate warming relate zonal wind anomalies in the upper troposphere to SST patterns of individual strong El Niños to estimate a possible effect of the relative AAM on length-of-day variations.
NASA Astrophysics Data System (ADS)
Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-05-01
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks.
Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-01-01
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks. PMID:27243577
Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-05-31
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks.
Lunn, Judith; Lewis, Charlie; Sherlock, Christopher
2015-02-01
Children with epilepsy (CWE) have social difficulties that can persist into adulthood, and this could be related to problems with understanding others' thoughts, feelings, and intentions. This study assessed children's ability to interpret and reason on mental and emotional states (Theory of Mind) and examined the relationships between task scores and reports of communication and behavior. Performance of 56 CWE (8-16years of age) with below average IQ (n=17) or an average IQ (n=39) was compared with that of 62 healthy controls with an average IQ (6-16years of age) on cognition, language, and two advanced Theory of Mind (ToM) tasks that required children to attribute mental or emotional states to eye regions and to reason on internal mental states in order to explain behavior. The CWE-below average group were significantly poorer in both ToM tasks compared with controls. The CWE - average group showed a significantly poorer ability to reason on mental states in order to explain behavior, a difference that remained after accounting for lower IQ and language deficits. Poor ToM skills were related to increased communication and attention problems in both CWE groups. There is a risk for atypical social understanding in CWE, even for children with average cognitive function. Copyright © 2014 Elsevier Inc. All rights reserved.
2009-01-01
Sudden cardiac and cerebral events are most common in the morning. A fundamental question is whether these events are triggered by the increase in physical activity after waking, and/or a result of circadian variation in the responses of circulatory function to exercise. Although signaling pathways from the master circadian clock in the suprachiasmatic nuclei to sites of circulatory control are not yet understood, it is known that cerebral blood flow, autoregulation and cerebrovascular reactivity to changes in CO2 are impaired in the morning and, therefore, could explain the increased risk of cerebrovascular events. Blood pressure (BP) and the rate pressure product (RPP) show marked ‘morning surges’ when people are studied in free-living conditions, making the rupture of a fragile atherosclerotic plaque and sudden cardiac event more likely. Since cerebral autoregulation is reduced in the morning, this surge in BP may also exacerbate the risk of hemorrhagic and ischemic strokes in the presence of other acute and chronic risk factors. Increased sympathetic activity, decreased endothelial function, and increased platelet aggregability could also be important in explaining the morning peak in cardiac and cerebral events but how these factors respond to exercise at different times of day is unclear. Evidence is emerging that the exercise-related responses of BP and RPP are increased in the morning when prior sleep is controlled. We recommend that such ‘semi-constant routine’ protocols are employed to examine the relative influence of the body clock and exogenous factors on the 24-h variation in other circulatory factors. PMID:19826832
Nahum-Shani, Inbal; Bamberger, Peter A
2011-01-01
Seeking to explain mixed empirical findings regarding the buffering effect of social support on work-based stress-strain relations, we posit that whether an increase in the level of support received buffers or exacerbates the harmful effects of workload on employee health and well-being is contingent upon the general pattern characterizing an employee supportive exchanges across his/her close relationships. Specifically, we propose that the buffering effect of receiving social support depends on whether the employee perceives his/her social exchanges as reciprocal (support given equals support received), under-reciprocating (support given exceeds support received), or over-reciprocating (support received exceeds support given). Based on longitudinal data collected from a random sample of blue-collar workers, our findings support our predictions, indicating that the buffering effect of social support on the relationship between work hours (on the one hand) and employee health and well-being (on the other) varies as a function of the pattern of exchange relations between an employee and his/her close support providers.
Anxiety and feedback processing in a gambling task: Contributions of time-frequency theta and delta.
Ellis, Jessica S; Watts, Adreanna T M; Schmidt, Norman; Bernat, Edward M
2018-05-02
The feedback negativity (FN) event-related potential (ERP) is widely studied during gambling feedback tasks. However, research on FN and anxiety is minimal and the findings are mixed. To clarify these discrepancies, the current study (N = 238) used time-frequency analysis to disentangle overlapping contributions of delta (0-3 Hz) and theta (3-7 Hz) to feedback processing in a clinically anxious sample, with severity assessed through general worry and physiological arousal scales. Greater general worry showed enhanced delta- and theta-FN broadly across both gain and loss conditions, with theta-FN stronger for losses. Regressions indicated delta-FN maintained unique effects, accounted for theta, and explained the blunted time domain FN for general worry. Increased delta was also associated with physiological arousal, but the effects were accounted for by general worry. Broadly, anxiety-related alterations in feedback processing can be explained by an overall heightened sensitivity to feedback as represented by enhanced delta-FN in relation to the general worry facet of anxiety. Copyright © 2018 Elsevier B.V. All rights reserved.
Nahum-Shani, Inbal; Bamberger, Peter A.
2010-01-01
Seeking to explain mixed empirical findings regarding the buffering effect of social support on work-based stress-strain relations, we posit that whether an increase in the level of support received buffers or exacerbates the harmful effects of workload on employee health and well-being is contingent upon the general pattern characterizing an employee supportive exchanges across his/her close relationships. Specifically, we propose that the buffering effect of receiving social support depends on whether the employee perceives his/her social exchanges as reciprocal (support given equals support received), under-reciprocating (support given exceeds support received), or over-reciprocating (support received exceeds support given). Based on longitudinal data collected from a random sample of blue-collar workers, our findings support our predictions, indicating that the buffering effect of social support on the relationship between work hours (on the one hand) and employee health and well-being (on the other) varies as a function of the pattern of exchange relations between an employee and his/her close support providers. PMID:21152110
NASA Astrophysics Data System (ADS)
Gaitan, S.; ten Veldhuis, J. A. E.
2015-06-01
Cities worldwide are challenged by increasing urban flood risks. Precise and realistic measures are required to reduce flooding impacts. However, currently implemented sewer and topographic models do not provide realistic predictions of local flooding occurrence during heavy rain events. Assessing other factors such as spatially distributed rainfall, socioeconomic characteristics, and social sensing, may help to explain probability and impacts of urban flooding. Several spatial datasets have been recently made available in the Netherlands, including rainfall-related incident reports made by citizens, spatially distributed rain depths, semidistributed socioeconomic information, and buildings age. Inspecting the potential of this data to explain the occurrence of rainfall related incidents has not been done yet. Multivariate analysis tools for describing communities and environmental patterns have been previously developed and used in the field of study of ecology. The objective of this paper is to outline opportunities for these tools to explore urban flooding risks patterns in the mentioned datasets. To that end, a cluster analysis is performed. Results indicate that incidence of rainfall-related impacts is higher in areas characterized by older infrastructure and higher population density.
McCartney, G; Bouttell, J; Craig, N; Craig, P; Graham, L; Lakha, F; Lewsey, J; McAdams, R; MacPherson, M; Minton, J; Parkinson, J; Robinson, M; Shipton, D; Taulbut, M; Walsh, D; Beeston, C
2016-03-01
To provide a basis for evaluating post-2007 alcohol policy in Scotland, this paper tests the extent to which pre-2007 policy, the alcohol market, culture or clinical changes might explain differences in the magnitude and trends in alcohol-related mortality outcomes in Scotland compared to England & Wales (E&W). Rapid literature reviews, descriptive analysis of routine data and narrative synthesis. We assessed the impact of pre-2007 Scottish policy and policy in the comparison areas in relation to the literature on effective alcohol policy. Rapid literature reviews were conducted to assess cultural changes and the potential role of substitution effects between alcohol and illicit drugs. The availability of alcohol was assessed by examining the trends in the number of alcohol outlets over time. The impact of clinical changes was assessed in consultation with key informants. The impact of all the identified factors were then summarised and synthesised narratively. The companion paper showed that part of the rise and fall in alcohol-related mortality in Scotland, and part of the differing trend to E&W, were predicted by a model linking income trends and alcohol-related mortality. Lagged effects from historical deindustrialisation and socio-economic changes exposures also remain plausible from the available data. This paper shows that policy differences or changes prior to 2007 are unlikely to have been important in explaining the trends. There is some evidence that aspects of alcohol culture in Scotland may be different (more concentrated and home drinking) but it seems unlikely that this has been an important driver of the trends or the differences with E&W other than through interaction with changing incomes and lagged socio-economic effects. Substitution effects with illicit drugs and clinical changes are unlikely to have substantially changed alcohol-related harms: however, the increase in alcohol availability across the UK is likely to partly explain the rise in alcohol-related mortality during the 1990s. Future policy should ensure that alcohol affordability and availability, as well as socio-economic inequality, are reduced, in order to maintain downward trends in alcohol-related mortality in Scotland. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Geographic techniques and recent applications of remote sensing to landscape-water quality studies
Griffith, J.A.
2002-01-01
This article overviews recent advances in studies of landscape-water quality relationships using remote sensing techniques. With the increasing feasibility of using remotely-sensed data, landscape-water quality studies can now be more easily performed on regional, multi-state scales. The traditional method of relating land use and land cover to water quality has been extended to include landscape pattern and other landscape information derived from satellite data. Three items are focused on in this article: 1) the increasing recognition of the importance of larger-scale studies of regional water quality that require a landscape perspective; 2) the increasing importance of remotely sensed data, such as the imagery-derived normalized difference vegetation index (NDVI) and vegetation phenological metrics derived from time-series NDVI data; and 3) landscape pattern. In some studies, using landscape pattern metrics explained some of the variation in water quality not explained by land use/cover. However, in some other studies, the NDVI metrics were even more highly correlated to certain water quality parameters than either landscape pattern metrics or land use/cover proportions. Although studies relating landscape pattern metrics to water quality have had mixed results, this recent body of work applying these landscape measures and satellite-derived metrics to water quality analysis has demonstrated their potential usefulness in monitoring watershed conditions across large regions.
Egg size variation among tropical and temperate songbirds: An embryonic temperature hypothesis
Martin, Thomas E.
2008-01-01
Species with “slow” life history strategies (long life, low fecundity) are thought to produce high-quality offspring by investing in larger, but fewer, young. Larger eggs are indeed associated with fewer eggs across taxa and can yield higher-quality offspring. Tropical passerines appear to follow theory because they commonly exhibit slow life history strategies and produce larger, but fewer, eggs compared with northern species. Yet, I show here that relative egg mass (corrected for adult mass) varies extensively in the tropics and subtropics for the same clutch size, and this variation is unexplained. I propose a hypothesis to explain egg size variation both within the tropics and between latitudes: Relative egg mass increases in species with cooler egg temperatures and longer embryonic periods to offset associated increases in energetic requirements of embryos. Egg temperatures of birds are determined by parental incubation behavior and are often cooler among tropical passerines because of reduced parental attentiveness of eggs. Here, I show that cooler egg temperatures and longer embryonic periods explained the enigmatic variation in egg mass within and among regions, based on field studies in tropical Venezuela (36 species), subtropical Argentina (16 species), and north temperate Arizona (20 species). Alternative explanations are not supported. Thus, large egg sizes may reflect compensation for increased energetic requirements of cool egg temperatures and long embryonic periods that result from reduced parental attentiveness in tropical birds. PMID:18591674
van Dillen, Sonja M E; Hiddink, Gerrit Jan; Koelen, Maria A; de Graaf, Cees; van Woerkum, Cees M J
2008-05-01
To unravel the concept of nutrition awareness, as it relates to risky personal nutrition-related behaviours, and to assess the sociodemographic and psychosocial correlates of nutrition awareness. Data were collected in a cross-sectional study with the aid of a face-to-face interview-assisted questionnaire that was based on the Precaution Adoption Process Model and Stages of Change Model. Dutch consumer homes. Six hundred and three Dutch adults aged 18 to 80 years, selected from a panel. Our model explains nutrition awareness well (explained variance 53.7%). Psychosocial correlates were involvement with nutrition, health awareness, association with healthy food, perceived relevance of eating less fat, association with necessity, perceived relevance of vitamins, and perceived attributes of independent organisations. Sociodemographic correlates were gender and age. The relationship between nutrition awareness and nutrition-related behaviours proved to be very complicated. The value of our study is that it unravels the concept of nutrition awareness. Understanding the correlates of nutrition awareness can contribute to a more effective application of behavioural change models. Our results support increasing involvement with nutrition through personalising and tailoring to the motivational stage.
Dispersal Limitations on Fish Community Recovery Following Long-term Water Quality Remediation
McManamay, Ryan A.; Jett, Robert T.; Ryon, Michael G.; ...
2016-02-22
Holistic restoration approaches, such as water quality remediation, are likely to meet conservation objectives because they are typically implemented at watershed scales, as opposed to individual stream reaches. However, habitat fragmentation may impose constraints on the ecological effectiveness of holistic restoration strategies by limiting colonization following remediation. We questioned the importance of dispersal limitations to fish community recovery following long-term water quality remediation and species reintroductions across the White Oak Creek (WOC) watershed near Oak Ridge, Tennessee (USA). Long-term (26 years) responses in fish species richness and biomass to water quality remediation were evaluated in light of habitat fragmentation andmore » population isolation from instream barriers, which varied in their passage potential. In addition, ordination techniques were used to determine the relative importance of habitat connectivity and water quality, in explaining variation fish communities relative to environmental fluctuations, i.e. streamflow. Ecological recovery (changes in richness) at each site was negatively related to barrier index, a measure of community isolation by barriers relative to stream distance. Following species reintroductions, dispersal by fish species was consistently in the downstream direction and upstream passage above barriers was non-existent. The importance of barrier index in explaining variation in fish communities was stronger during higher flow conditions, but decreased over time an indication of increasing community stability and loss of seasonal migrants. Compared to habitat fragmentation, existing water quality concerns (i.e., outfalls, point source discharges) were unrelated to ecological recovery, but explained relatively high variation in community dynamics. Our results suggest that habitat fragmentation limited the ecological effectiveness of intensive water quality remediation efforts and fish reintroduction efforts by impeding recolonization at isolated stream reaches.« less
Biogeographical Interpretation of Elevational Patterns of Genus Diversity of Seed Plants in Nepal
Li, Miao; Feng, Jianmeng
2015-01-01
This study tests if the biogeographical affinities of genera are relevant for explaining elevational plant diversity patterns in Nepal. We used simultaneous autoregressive (SAR) models to investigate the explanatory power of several predictors in explaining the diversity-elevation relationships shown in genera with different biogeographical affinities. Delta akaike information criterion (ΔAIC) was used for multi-model inferences and selections. Our results showed that both the total and tropical genus diversity peaked below the mid-point of the elevational gradient, whereas that of temperate genera had a nearly symmetrical, unimodal relationship with elevation. The proportion of temperate genera increased markedly with elevation, while that of tropical genera declined. Compared to tropical genera, temperate genera had wider elevational ranges and were observed at higher elevations. Water-related variables, rather than mid-domain effects (MDE), were the most significant predictors of elevational patterns of tropical genus diversity. The temperate genus diversity was influenced by energy availability, but only in quadratic terms of the models. Though climatic factors and mid-domain effects jointly explained most of the variation in the diversity of temperate genera with elevation, the former played stronger roles. Total genus diversity was most strongly influenced by climate and the floristic overlap of tropical and temperate floras, while the influences of mid-domain effects were relatively weak. The influences of water-related and energy-related variables may vary with biogeographical affinities. The elevational patterns may be most closely related to climatic factors, while MDE may somewhat modify the patterns. Caution is needed when investigating the causal factors underlying diversity patterns for large taxonomic groups composed of taxa of different biogeographical affinities. Right-skewed diversity-elevation patterns may be produced by the differential response of taxa with varying biogeographical affinities to climatic factors and MDE. PMID:26488164
Biogeographical Interpretation of Elevational Patterns of Genus Diversity of Seed Plants in Nepal.
Li, Miao; Feng, Jianmeng
2015-01-01
This study tests if the biogeographical affinities of genera are relevant for explaining elevational plant diversity patterns in Nepal. We used simultaneous autoregressive (SAR) models to investigate the explanatory power of several predictors in explaining the diversity-elevation relationships shown in genera with different biogeographical affinities. Delta akaike information criterion (ΔAIC) was used for multi-model inferences and selections. Our results showed that both the total and tropical genus diversity peaked below the mid-point of the elevational gradient, whereas that of temperate genera had a nearly symmetrical, unimodal relationship with elevation. The proportion of temperate genera increased markedly with elevation, while that of tropical genera declined. Compared to tropical genera, temperate genera had wider elevational ranges and were observed at higher elevations. Water-related variables, rather than mid-domain effects (MDE), were the most significant predictors of elevational patterns of tropical genus diversity. The temperate genus diversity was influenced by energy availability, but only in quadratic terms of the models. Though climatic factors and mid-domain effects jointly explained most of the variation in the diversity of temperate genera with elevation, the former played stronger roles. Total genus diversity was most strongly influenced by climate and the floristic overlap of tropical and temperate floras, while the influences of mid-domain effects were relatively weak. The influences of water-related and energy-related variables may vary with biogeographical affinities. The elevational patterns may be most closely related to climatic factors, while MDE may somewhat modify the patterns. Caution is needed when investigating the causal factors underlying diversity patterns for large taxonomic groups composed of taxa of different biogeographical affinities. Right-skewed diversity-elevation patterns may be produced by the differential response of taxa with varying biogeographical affinities to climatic factors and MDE.
Two Independent Contributions to Step Variability during Over-Ground Human Walking
Collins, Steven H.; Kuo, Arthur D.
2013-01-01
Human walking exhibits small variations in both step length and step width, some of which may be related to active balance control. Lateral balance is thought to require integrative sensorimotor control through adjustment of step width rather than length, contributing to greater variability in step width. Here we propose that step length variations are largely explained by the typical human preference for step length to increase with walking speed, which itself normally exhibits some slow and spontaneous fluctuation. In contrast, step width variations should have little relation to speed if they are produced more for lateral balance. As a test, we examined hundreds of overground walking steps by healthy young adults (N = 14, age < 40 yrs.). We found that slow fluctuations in self-selected walking speed (2.3% coefficient of variation) could explain most of the variance in step length (59%, P < 0.01). The residual variability not explained by speed was small (1.5% coefficient of variation), suggesting that step length is actually quite precise if not for the slow speed fluctuations. Step width varied over faster time scales and was independent of speed fluctuations, with variance 4.3 times greater than that for step length (P < 0.01) after accounting for the speed effect. That difference was further magnified by walking with eyes closed, which appears detrimental to control of lateral balance. Humans appear to modulate fore-aft foot placement in precise accordance with slow fluctuations in walking speed, whereas the variability of lateral foot placement appears more closely related to balance. Step variability is separable in both direction and time scale into balance- and speed-related components. The separation of factors not related to balance may reveal which aspects of walking are most critical for the nervous system to control. PMID:24015308
Dispersal Limitations on Fish Community Recovery Following Long-term Water Quality Remediation
DOE Office of Scientific and Technical Information (OSTI.GOV)
McManamay, Ryan A.; Jett, Robert T.; Ryon, Michael G.
Holistic restoration approaches, such as water quality remediation, are likely to meet conservation objectives because they are typically implemented at watershed scales, as opposed to individual stream reaches. However, habitat fragmentation may impose constraints on the ecological effectiveness of holistic restoration strategies by limiting colonization following remediation. We questioned the importance of dispersal limitations to fish community recovery following long-term water quality remediation and species reintroductions across the White Oak Creek (WOC) watershed near Oak Ridge, Tennessee (USA). Long-term (26 years) responses in fish species richness and biomass to water quality remediation were evaluated in light of habitat fragmentation andmore » population isolation from instream barriers, which varied in their passage potential. In addition, ordination techniques were used to determine the relative importance of habitat connectivity and water quality, in explaining variation fish communities relative to environmental fluctuations, i.e. streamflow. Ecological recovery (changes in richness) at each site was negatively related to barrier index, a measure of community isolation by barriers relative to stream distance. Following species reintroductions, dispersal by fish species was consistently in the downstream direction and upstream passage above barriers was non-existent. The importance of barrier index in explaining variation in fish communities was stronger during higher flow conditions, but decreased over time an indication of increasing community stability and loss of seasonal migrants. Compared to habitat fragmentation, existing water quality concerns (i.e., outfalls, point source discharges) were unrelated to ecological recovery, but explained relatively high variation in community dynamics. Our results suggest that habitat fragmentation limited the ecological effectiveness of intensive water quality remediation efforts and fish reintroduction efforts by impeding recolonization at isolated stream reaches.« less
Legay, N.; Baxendale, C.; Grigulis, K.; Krainer, U.; Kastl, E.; Schloter, M.; Bardgett, R. D.; Arnoldi, C.; Bahn, M.; Dumont, M.; Poly, F.; Pommier, T.; Clément, J. C.; Lavorel, S.
2014-01-01
Background and Aims Abiotic properties of soil are known to be major drivers of the microbial community within it. Our understanding of how soil microbial properties are related to the functional structure and diversity of plant communities, however, is limited and largely restricted to above-ground plant traits, with the role of below-ground traits being poorly understood. This study investigated the relative contributions of soil abiotic properties and plant traits, both above-ground and below-ground, to variations in microbial processes involved in grassland nitrogen turnover. Methods In mountain grasslands distributed across three European sites, a correlative approach was used to examine the role of a large range of plant functional traits and soil abiotic factors on microbial variables, including gene abundance of nitrifiers and denitrifiers and their potential activities. Key Results Direct effects of soil abiotic parameters were found to have the most significant influence on the microbial groups investigated. Indirect pathways via plant functional traits contributed substantially to explaining the relative abundance of fungi and bacteria and gene abundances of the investigated microbial communities, while they explained little of the variance in microbial activities. Gene abundances of nitrifiers and denitrifiers were most strongly related to below-ground plant traits, suggesting that they were the most relevant traits for explaining variation in community structure and abundances of soil microbes involved in nitrification and denitrification. Conclusions The results suggest that consideration of plant traits, and especially below-ground traits, increases our ability to describe variation in the abundances and the functional characteristics of microbial communities in grassland soils. PMID:25122656
Hoffmann, Ferdinand; Singer, Tania; Steinbeis, Nikolaus
2015-01-01
This study investigated the cognitive mechanisms underlying age-related differences in emotional egocentricity bias (EEB) between children (aged 7-12 years, n = 30) and adults (aged 20-30 years, n = 30) using a novel paradigm of visuogustatory stimulation to induce pleasant and unpleasant emotions. Both children and adults showed an EBB, but that of children was larger. The EEB did not correlate with other measures of egocentricity. Crucially, the developmental differences in EEB were mediated by age-related changes in conflict processing and not visual perspective taking, response inhibition, or processing speed. This indicates that different types of egocentricity develop independently of one another and that the increased ability to overcome EEB can be explained by age-related improvements in conflict processing. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.
Otte, Willem M; van Diessen, Eric; Bell, Gail S; Sander, Josemir W
2013-12-01
In old and modern times and across cultures, recurrent seizures have been attributed to the lunar phase. It is unclear whether this relationship should be classified as a myth or whether a true connection exists between moon phases and seizures. We analyzed the worldwide aggregated search queries related to epilepsy health-seeking behavior between 2005 and 2012. Epilepsy-related Internet searches increased in periods with a high moon illumination. The overall association was weak (r=0.11, 95% confidence interval: 0.07 to 0.14) but seems to be higher than most control search queries not related to epilepsy. Increased sleep deprivation during periods of full moon might explain this positive association and warrants further study into epilepsy-related health-seeking behavior on the Internet, the lunar phase, and its contribution to nocturnal luminance. © 2013.
Anson, Eric; Bigelow, Robin T.; Swenor, Bonnielin; Deshpande, Nandini; Studenski, Stephanie; Jeka, John J.; Agrawal, Yuri
2017-01-01
Postural sway increases with age and peripheral sensory disease. Whether, peripheral sensory function is related to postural sway independent of age in healthy adults is unclear. Here, we investigated the relationship between tests of visual function (VISFIELD), vestibular function (CANAL or OTOLITH), proprioceptive function (PROP), and age, with center of mass sway area (COM) measured with eyes open then closed on firm and then a foam surface. A cross-sectional sample of 366 community dwelling healthy adults from the Baltimore Longitudinal Study of Aging was tested. Multiple linear regressions examined the association between COM and VISFIELD, PROP, CANAL, and OTOLITH separately and in multi-sensory models controlling for age and gender. PROP dominated sensory prediction of sway across most balance conditions (β's = 0.09–0.19, p's < 0.001), except on foam eyes closed where CANAL function loss was the only significant sensory predictor of sway (β = 2.12, p < 0.016). Age was not a consistent predictor of sway. This suggests loss of peripheral sensory function explains much of the age-associated increase in sway. PMID:28676758
Booth, Amy R; Norman, Paul; Harris, Peter R; Goyder, Elizabeth
2014-02-01
The study sought to (1) explain intentions to get tested for chlamydia regularly in a group of young people living in deprived areas using the theory of planned behaviour (TPB); and (2) test whether self-identity explained additional variance in testing intentions. A cross-sectional design was used for this study. Participants (N = 278, 53% male; M = 17.05 years) living in deprived areas of a UK city were recruited from a vocational education setting. Participants completed a self-administered questionnaire, including measures of attitude, injunctive subjective norm, descriptive norm, perceived behavioural control, self-identity, intention and past behaviour in relation to getting tested for chlamydia regularly. The TPB explained 43% of the variance in chlamydia testing intentions with all variables emerging as significant predictors. However, self-identity explained additional variance in intentions (ΔR(2) = .22) and emerged as the strongest predictor, even when controlling for past behaviour. The study identified the key determinants of intention to get tested for chlamydia regularly in a sample of young people living in areas of increased deprivation: a hard-to-reach, high-risk population. The findings indicate the key variables to target in interventions to promote motivation to get tested for chlamydia regularly in equivalent samples, amongst which self-identity is critical. What is already known on this subject? Young people living in deprived areas have been identified as an at-risk group for chlamydia. Qualitative research has identified several themes in relation to factors affecting the uptake of chlamydia testing, which fit well with the constructs of the Theory of Planned Behaviour (TPB). Identity concerns have also been identified as playing an important part in young people's chlamydia testing decisions. What does this study add? TPB explained 43% of the variance in chlamydia testing intentions and all variables were significant predictors. Self-identity explained additional 22% of the variance in intentions and emerged as the strongest predictor. Indicates key variables to target in interventions to promote regular chlamydia testing in deprived young people. © 2013 The British Psychological Society.
Socioeconomic differences in school dropout among young adults: the role of social relations.
Winding, Trine Nøhr; Andersen, Johan Hviid
2015-10-15
School dropout in adolescence is an important social determinant of health inequality in a lifetime perspective. It is commonly accepted that parental background factors are associated with later dropout, but to what extent social relations mediate this association is not yet fully understood. To investigate the effect of social relations on the association between parental socioeconomic position and school dropout in the Danish youth cohort Vestliv. This prospective study used data from questionnaires in 2004 and 2007 and register data in 2004 and 2010. The study population consisted of 3,054 persons born in 1989. Information on dropout was dichotomised into those who had completed a secondary education/were still attending one and those who had dropped out/had never attended a secondary education. Logistic regression analyses were used to investigate associations between parental socioeconomic position and dropout at age 21, taking into account effects of social relations at age 15 and 18. A large proportion of young people were having problems with social relations at age 15 and 18. In general, social relations were strongly related to not completing a secondary education, especially among girls. For instance, 18-year-old girls finding family conflicts difficult to handle had a 2.6-fold increased risk of not completing a secondary education. Young people from low socioeconomic position families had approximately a 3-fold higher risk of not completing a secondary education compared to young people from high position families, and the estimates did not change greatly after adjustment for social relations with family or friends. Poor relations with teachers and classmates at age 18 explained a substantial part of the association between income and dropout among both girls and boys. The study confirmed a social gradient in completion of secondary education. Despite the fact that poor social relations at age 15 and 18 were related to dropout at age 21, social relations with family and friends only explained a minor part of the socioeconomic differences in dropout. However, poor social relations with teachers and classmates at age 18 explain a substantial part of the socioeconomic difference in dropout from secondary education.
Changes in structure and geometric properties of human hair by aging.
Nagase, Shinobu; Kajiura, Yoshio; Mamada, Akira; Abe, Hiroko; Shibuichi, Satoshi; Satoh, Naoki; Itou, Takashi; Shinohara, Yuya; Amemiya, Yoshiyuki
2009-01-01
To clarify hair changes by aging, the effect of age on hair properties was investigated from macro- to microscopic view points. Sensory hair luster tests were performed on 230 Japanese females from 10 to 70 years of age, revealing that hair luster decreases with age. The age dependence of the hair diameter and the ellipticity of the hair cross section could not explain luster reduction by aging. It has been determined that an irregular increase in fiber curvature occurs with age and is a cause of luster reduction with aging. A detailed structural analysis by synchrotron radiation microbeam X-ray diffraction revealed that the inhomogeneity in the lateral distribution of the hair microstructure increased with age and relates to the irregular increase in curvature. Such an increase in curvature is one of the important factors that leads to a poor alignment of hairs and luster reduction, and is related to the appearance of aging hair.
Tree diversity in relation to tree height: alternative perspectives.
Givnish, Thomas J
2017-03-01
Marks et al. (Ecol. Lett., 19, 2016, 743-751) show that tree diversity increases with tree height in North America and argue it reflects habitat 'suitability'. This finding conflicts with classical results, lacks controls for covariates of tree height, and can be explained alternatively using the modified Janzen-Connell effect and regional variance in habitats. © 2017 John Wiley & Sons Ltd/CNRS.
Meeting students halfway: Increasing self-efficacy and promoting knowledge change in astronomy
NASA Astrophysics Data System (ADS)
Bailey, Janelle M.; Lombardi, Doug; Cordova, Jacqueline R.; Sinatra, Gale M.
2017-12-01
Two motivational factors—self-efficacy and interest—may be especially relevant to deepening students' understanding of astronomy. We examined the relationship between students' self-efficacy for, interest in learning about, and changes in their knowledge of stars, as measured by the Star Properties Concept Inventory (SPCI). Approximately 700 undergraduate students taking introductory astronomy responded to surveys at the start and end of their semester-long course. A sequential multiple regression analysis showed that self-efficacy post explains an appreciable percentage of variance in SPCI posttest scores, more than twice the percentage explained by all the pretest variables (SPCI, self-efficacy, and interest) combined. Knowledge and self-efficacy improved significantly over instruction; interest did not. Follow-up analyses revealed that instructors whose classes increased in self-efficacy also had the greatest increases in knowledge scores. Interviews with these instructors suggest they provide their students with more opportunities for mastery experiences with elaborated, performance-related feedback, as well as strong positive verbal persuasion and vicarious experiences through peer instruction. Through increased understanding of the relationship between motivational constructs (e.g., self-efficacy, interest) and knowledge, we can both improve our models and better inform instruction.
Neutrophil formyl-peptide receptors. Relationship to peptide-induced responses and emphysema.
Stockley, R A; Grant, R A; Llewellyn-Jones, C G; Hill, S L; Burnett, D
1994-02-01
A reproducible assay was established to assess the number of formyl-peptide receptors expressed on the surface of human polymorphonuclear leukocytes (PMN). Using this assay the number of receptors was shown to demonstrate wide within- and between-subject variability. However, the receptor numbers were related to the chemotactic response (r = 0.572) and degranulation response (r = 0.512) to the peptide formyl-methionyl-leucyl-phenylalanine. Subsequent studies showed increased receptor numbers on PMN from patients with emphysema (median, 459 x 10(3)/cell; range, 207 to 1,080) as compared with age-matched control subjects (median, 288; range, 168 to 519; p < 0.02), which may explain the increased chemotactic response of the PMN to formyl peptides. This difference was not observed in patients with bronchiectasis, suggesting that the increased receptor number is a feature of emphysema. Furthermore, the increase was largely a feature of smokers with emphysema (median, 463; range, 362 to 1,080), whereas age-matched smokers without emphysema had lower numbers of receptors (p < 0.001; median, 332; range, 243 to 411). This observation suggests a mechanism that may explain the susceptibility of some smokers to the development of emphysema.
Marcondes, Rodrigo R; Maliqueo, Manuel; Fornes, Romina; Benrick, Anna; Hu, Min; Ivarsson, Niklas; Carlström, Mattias; Cushman, Samuel W; Stenkula, Karin G; Maciel, Gustavo A R; Stener-Victorin, Elisabet
2017-06-15
Here we hypothesized that exercise in dihydrotestosterone (DHT) or letrozole (LET)-induced polycystic ovary syndrome mouse models improves impaired insulin and glucose metabolism, adipose tissue morphology, and expression of genes related to adipogenesis, lipid metabolism, Notch pathway and browning in inguinal and mesenteric fat. DHT-exposed mice had increased body weight, increased number of large mesenteric adipocytes. LET-exposed mice displayed increased body weight and fat mass, decreased insulin sensitivity, increased frequency of small adipocytes and increased expression of genes related to lipolysis in mesenteric fat. In both models, exercise decreased fat mass and inguinal and mesenteric adipose tissue expression of Notch pathway genes, and restored altered mesenteric adipocytes morphology. In conclusion, exercise restored mesenteric adipocytes morphology in DHT- and LET-exposed mice, and insulin sensitivity and mesenteric expression of lipolysis-related genes in LET-exposed mice. Benefits could be explained by downregulation of Notch, and modulation of browning and lipolysis pathways in the adipose tissue. Copyright © 2017 Elsevier B.V. All rights reserved.
Seizing an opportunity: increasing use of cessation services following a tobacco tax increase.
Keller, Paula A; Greenseid, Lija O; Christenson, Matthew; Boyle, Raymond G; Schillo, Barbara A
2015-04-10
Tobacco tax increases are associated with increases in quitline calls and reductions in smoking prevalence. In 2013, ClearWay Minnesota(SM) conducted a six-week media campaign promoting QUITPLAN® Services (QUITPLAN Helpline and quitplan.com) to leverage the state's tax increase. The purpose of this study was to ascertain the association of the tax increase and media campaign on call volumes, web visits, and enrollments in QUITPLAN Services. In this observational study, call volume, web visits, enrollments, and participant characteristics were analyzed for the periods June-August 2012 and June-August 2013. Enrollment data and information about media campaigns were analyzed using multivariate regression analysis to determine the association of the tax increase on QUITPLAN Services while controlling for media. There was a 160% increase in total combined calls and web visits, and an 81% increase in enrollments in QUITPLAN Services. Helpline call volumes and enrollments declined back to prior year levels approximately six weeks after the tax increase. Visits to and enrollments in quitplan.com also declined, but increased again in mid-August. The tax increase and media explained over 70% of variation in enrollments in the QUITPLAN Helpline, with media explaining 34% of the variance and the tax increase explaining an additional 36.1% of this variance. However, media explained 64% of the variance in quitplan.com enrollments, and the tax increase explained an additional 7.6% of this variance. Since tax increases occur infrequently, these policy changes must be fully leveraged as quickly as possible to help reduce prevalence.
Lundy, J Jason; Coons, Stephen Joel; Wendel, Christopher; Hornbrook, Mark C; Herrinton, Lisa; Grant, Marcia; Krouse, Robert S
2009-03-01
The purpose of this analysis was to determine the unique contribution of household income to the variance explained in psychological well-being (PWB) among a sample of colorectal cancer (CRC) survivors. This study is a secondary analysis of data collected as part of the Health-Related Quality of Life in Long-Term Colorectal Cancer Survivors Study, which included CRC survivors with (cases) and without (controls) ostomies. The dataset included socio-demographic, health status, and health-related quality of life (HRQOL) information. HRQOL was assessed with the modified City of Hope Quality of Life (mCOH-QOL)-Ostomy questionnaire and SF-36v2. To assess the relationship between income and PWB, a hierarchical linear regression model was constructed combining data from both cases and controls. After accounting for the proportion of variance in PWB explained by the other independent variables in the model, the additional variance explained by income was significant (R (2) increased from 0.228 to 0.250; P = 0.006). Although the study design does not allow causal inference, these results demonstrate a significant relationship between income and PWB in CRC survivors. The findings suggest that for non-randomized group comparisons of HRQOL, income should, at the very least, be included as a control variable in the analysis.
Does sexual selection explain human sex differences in aggression?
Archer, John
2009-08-01
I argue that the magnitude and nature of sex differences in aggression, their development, causation, and variability, can be better explained by sexual selection than by the alternative biosocial version of social role theory. Thus, sex differences in physical aggression increase with the degree of risk, occur early in life, peak in young adulthood, and are likely to be mediated by greater male impulsiveness, and greater female fear of physical danger. Male variability in physical aggression is consistent with an alternative life history perspective, and context-dependent variability with responses to reproductive competition, although some variability follows the internal and external influences of social roles. Other sex differences, in variance in reproductive output, threat displays, size and strength, maturation rates, and mortality and conception rates, all indicate that male aggression is part of a sexually selected adaptive complex. Physical aggression between partners can be explained using different evolutionary principles, arising from the conflicts of interest between males and females entering a reproductive alliance, combined with variability following differences in societal gender roles. In this case, social roles are particularly important since they enable both the relatively equality in physical aggression between partners from Western nations, and the considerable cross-national variability, to be explained.
Monetary policy and the effects of oil price shocks on the Japanese economy
NASA Astrophysics Data System (ADS)
Lee, Byung Rhae
1998-12-01
The evidence of output decreases and price level increases following oil price shocks in the Japanese economy is presented in this paper. These negative effects of oil shocks are better explained by Hamilton's (1996) net oil price increase measure (NOPI) than by other oil measures. The fact that an oil shock has a statistically significant effect on the call money rate and real output and that the call money rate also has a statistically significant effect on real output appears to explain that the effects of oil price shocks on economic activity are partially attributed to contractionary monetary policy responses. The asymmetric effects of positive and negative oil shocks are also found in the Japanese economy and this asymmetry can also be partially explained by monetary policy responses. To assess the relative contribution of oil shocks and endogenous monetary policy responses to the economic downturns, I shut off the responses of the call money rate to oil shocks utilizing the impulse response results from the VAR model. Then, I re-run the VAR with the adjusted call money rate series. The empirical results show that around 30--40% of the negative effects of oil price shocks on the Japanese economy can be accounted for by oil shock induced monetary tightening.
Comoretto, Amanda
2017-01-01
Abstract Research has shown that children exposed to life adversity are at higher risk of negative developmental outcomes than those enduring lower stress levels. Life adversity can lead, among other things, to emotional and behavioural problems. Several factors have been studied to explain this relationship, with several investigators underlining the role of thought structures such as cognitive distortions, which refer to negatively biased information‐processing of external events. This can help explain why some individuals characterised by adverse personal life stories interpret ambiguous events in a negatively biased way. This study was aimed at assessing the mediating role of cognitive distortions in the longitudinal relationship between life adversity and two dimensions of psychopathology, namely, emotional and behavioural problems in 247 secondary school children attending three state secondary schools in one county in the South East of England. An increase in life adversity was associated with an increase in cognitive distortions, which was in turn related to a higher number of symptoms reflecting behavioural issues. In terms of practical applications, an effort to protect children from further exposure to adverse life events could represent a step forward to prevent the development of future behavioural problems in at‐risk children. PMID:28198138
Brain reorganization, not relative brain size, primarily characterizes anthropoid brain evolution.
Smaers, J B; Soligo, C
2013-05-22
Comparative analyses of primate brain evolution have highlighted changes in size and internal organization as key factors underlying species diversity. It remains, however, unclear (i) how much variation in mosaic brain reorganization versus variation in relative brain size contributes to explaining the structural neural diversity observed across species, (ii) which mosaic changes contribute most to explaining diversity, and (iii) what the temporal origin, rates and processes are that underlie evolutionary shifts in mosaic reorganization for individual branches of the primate tree of life. We address these questions by combining novel comparative methods that allow assessing the temporal origin, rate and process of evolutionary changes on individual branches of the tree of life, with newly available data on volumes of key brain structures (prefrontal cortex, frontal motor areas and cerebrocerebellum) for a sample of 17 species (including humans). We identify patterns of mosaic change in brain evolution that mirror brain systems previously identified by electrophysiological and anatomical tract-tracing studies in non-human primates and functional connectivity MRI studies in humans. Across more than 40 Myr of anthropoid primate evolution, mosaic changes contribute more to explaining neural diversity than changes in relative brain size, and different mosaic patterns are differentially selected for when brains increase or decrease in size. We identify lineage-specific evolutionary specializations for all branches of the tree of life covered by our sample and demonstrate deep evolutionary roots for mosaic patterns associated with motor control and learning.
Brain reorganization, not relative brain size, primarily characterizes anthropoid brain evolution
Smaers, J. B.; Soligo, C.
2013-01-01
Comparative analyses of primate brain evolution have highlighted changes in size and internal organization as key factors underlying species diversity. It remains, however, unclear (i) how much variation in mosaic brain reorganization versus variation in relative brain size contributes to explaining the structural neural diversity observed across species, (ii) which mosaic changes contribute most to explaining diversity, and (iii) what the temporal origin, rates and processes are that underlie evolutionary shifts in mosaic reorganization for individual branches of the primate tree of life. We address these questions by combining novel comparative methods that allow assessing the temporal origin, rate and process of evolutionary changes on individual branches of the tree of life, with newly available data on volumes of key brain structures (prefrontal cortex, frontal motor areas and cerebrocerebellum) for a sample of 17 species (including humans). We identify patterns of mosaic change in brain evolution that mirror brain systems previously identified by electrophysiological and anatomical tract-tracing studies in non-human primates and functional connectivity MRI studies in humans. Across more than 40 Myr of anthropoid primate evolution, mosaic changes contribute more to explaining neural diversity than changes in relative brain size, and different mosaic patterns are differentially selected for when brains increase or decrease in size. We identify lineage-specific evolutionary specializations for all branches of the tree of life covered by our sample and demonstrate deep evolutionary roots for mosaic patterns associated with motor control and learning. PMID:23536600
Height-related growth declines in ponderosa pine are not due to carbon limitation.
Sala, Anna; Hoch, Günter
2009-01-01
Decreased gas exchange as trees grow tall has been proposed to explain age-related growth declines in trees. We examined changes of mobile carbon stores (starch, sugars and lipids) with tree height in ponderosa pine (Pinus ponderosa) at two sites differing in water availability, and tested the following hypotheses: (1) carbon supply does not become increasingly limited as trees grow tall; rather, the concentration of mobile carbon compounds increases with tree height reflecting greater reductions of carbon sink activities relative to carbon assimilation; and (2) increases of stored mobile carbon compounds with tree height are greater in drier sites. Height-related growth reductions were associated with significant increases of non-structural carbohydrates (NSC) and lipid concentrations in all tissues in the upper canopy and of NSC in the bole. Lipid concentrations in the bole decreased with tree height, but such decrease is not necessarily inconsistent with non-limiting carbon supply in tall trees. Furthermore, we found stronger increases of mobile carbon stores with tree height at the dry site relative to the moist site. Our results provide first direct evidence that carbon supply does not limit growth in tall trees and that decreases of water availability might negatively impact growth processes more than net-photosynthesis.
Cheung, W S; Bhan, I; Lipton, S A
2000-06-16
Recent observations suggest that nitric oxide (NO(.)) can increase or decrease growth cone motility. Here, these apparently paradoxical results are explained by distinct actions of different NO-related species. Filopodial morphology of 223 rat retinal ganglion cells was monitored under computer-enhanced video microscopy in the presence of NO synthase (NOS) substrates or inhibitors, donors of specific NO-related species, and membrane-permeant cyclic nucleotide analogs. Physiological NOS activity induced filopodial outgrowth, whereas inhibition of NOS stabilized filopodia. Similar to NOS, nitrosonium (NO(+) transfer) and peroxynitrite (ONOO(-)), which can regulate the activity of growth-associated proteins by S-nitrosylation and oxidation, respectively, induced filopodial outgrowth. In contrast, NO(.), which stimulates guanylate cyclase to increase cGMP, stabilized filopodial activity. Thus disparate NO-related species may offer a dynamic process of filopodial growth regulation.
Socioeconomic Status and the Physical and Mental Health of Arab and Chaldean Americans in Michigan.
Samari, Goleen; McNall, Miles; Lee, KyungSook; Perlstadt, Harry; Nawyn, Stephanie
2018-06-05
Research that explains health of Arab and Chaldean Americans relative to the health of non-Arab White Americans is limited but steadily increasing. This study considers whether socioeconomic status moderates the relationship between race/ethnicity and physical and mental health. Data come from a state representative sample of Arab and Chaldean Americans-the 2013 Michigan Behavioral Risk Factor Survey and the 2013 Michigan Arab/Chaldean Behavioral Risk Factor Survey (N = 12,837 adults with 536 Arab/Chaldean Americans). Structural equation models examine whether socioeconomic status, operationalized as educational attainment, moderates the relationship between Arab/Chaldean identity and health, and whether physical activity, access to healthcare, and depression mediate the relationship between educational attainment and health. Results indicate that while Arab/Chaldean Americans have poor health relative to non-Arab White Americans, these differences are largely explained by educational differences. Depression, access to healthcare, and physical activity mediate the relationship between socioeconomic status and health of Arab/Chaldean Americans.
Can selection on nest size from nest predation explain the latitudinal gradient in clutch size?
Biancucci, Luis; Martin, Thomas E
2010-09-01
1. Latitudinal variation in clutch sizes of birds is a well described, but poorly understood pattern. Many hypotheses have been proposed, but few have been experimentally tested, and none have been universally accepted by researchers. 2. The nest size hypothesis posits that higher nest predation in the tropics favours selection for smaller nests and thereby constrains clutch size by shrinking available space for eggs and/or nestlings in the nest. We tested this hypothesis with an experiment in a tropical forest and a comparative study between temperate and tropical field sites. 3. Specifically, we tested if: (i) predation increased with nest size; (ii) tropical birds had smaller nests controlled for body size; and (iii) clutch size was explained by nest size controlled for body size. 4. Experimental swapping of nests of different sizes showed that nest predation increased with nest size in the tropical site. Moreover, nest predation rates were higher in species with larger nests in both sites. However, nest size, corrected for body mass and phylogeny, did not differ between sites and was not related to clutch size between sites. 5. Hence, nest predation can exert selection on nest size as predicted by the hypothesis. Nest size increased with adult body mass, such that adult size might indirectly influence reproductive success through effects on nest size and nest predation risk. Ultimately, however, selection from nest predation on nest size does not explain the smaller clutch sizes typical of the tropics.
Can selection on nest size from nest predation explain the latitudinal gradient in clutch size?
Biancucci, L.; Martin, T.E.
2010-01-01
1. Latitudinal variation in clutch sizes of birds is a well described, but poorly understood pattern. Many hypotheses have been proposed, but few have been experimentally tested, and none have been universally accepted by researchers. 2. The nest size hypothesis posits that higher nest predation in the tropics favours selection for smaller nests and thereby constrains clutch size by shrinking available space for eggs and/or nestlings in the nest. We tested this hypothesis with an experiment in a tropical forest and a comparative study between temperate and tropical field sites. 3. Specifically, we tested if: (i) predation increased with nest size; (ii) tropical birds had smaller nests controlled for body size; and (iii) clutch size was explained by nest size controlled for body size. 4. Experimental swapping of nests of different sizes showed that nest predation increased with nest size in the tropical site. Moreover, nest predation rates were higher in species with larger nests in both sites. However, nest size, corrected for body mass and phylogeny, did not differ between sites and was not related to clutch size between sites. 5. Hence, nest predation can exert selection on nest size as predicted by the hypothesis. Nest size increased with adult body mass, such that adult size might indirectly influence reproductive success through effects on nest size and nest predation risk. Ultimately, however, selection from nest predation on nest size does not explain the smaller clutch sizes typical of the tropics.
Modeling patterns of coral bleaching at a remote Central Pacific atoll.
Williams, Gareth J; Knapp, Ingrid S; Maragos, James E; Davy, Simon K
2010-09-01
A mild bleaching event (9.2% prevalence) at Palmyra Atoll occurred in response to the 2009 ENSO, when mean water temperature reached 29.8-30.1 degrees C. Prevalence among both abundant and sparse taxa varied with no clear pattern in susceptibility relating to coral morphology. Seven taxon-specific models showed that turbidity exacerbated while prior exposure to higher background temperatures alleviated bleaching, with these predictors explaining an average 16.3% and 11.5% variation in prevalence patterns, respectively. Positive associations occurred between bleaching prevalence and both immediate temperature during the bleaching event (average 8.4% variation explained) and increased sand cover (average 3.7%). Despite these associations, mean unexplained variation in prevalence equalled 59%. Lower bleaching prevalence in areas experiencing higher background temperatures suggests acclimation to temperature stress among several coral genera, while WWII modifications may still be impacting the reefs via shoreline sediment re-distribution and increased turbidity, exacerbating coral bleaching susceptibility during periods of high temperature stress. Copyright 2010 Elsevier Ltd. All rights reserved.
Selås, Vidar
2016-06-01
Herbivore cycles are often synchronized over larger areas than what could be explained by dispersal. In Norway, the 3-4 year lemming cycle usually show no more than a one-year time lag between different regions, despite distances of up to 1000 km. If important food plants are forced to reallocate defensive proteins in years with high seed production, spatially synchronized herbivore outbreaks may be due to climate-synchronized peaks in flowering. Because lemming peaks are expected to occur one year after a flowering peak, and the formation of flower buds is induced in the year before flowering, a two-year time lag between flower-inducing climate events and lemming peaks is predicted. At Hardangervidda, South Norway, the probability that a year was a population peak year of lemming during 1920-2014 increased with increasing midsummer atmospheric pressure two years earlier, even when the number of years since the previous peak was accounted for.
Land use, spatial scale, and stream systems: Lessons from an agricultural region
Vondracek, B.; Blann, K.L.; Cox, C.B.; Nerbonne, J.F.; Mumford, K.G.; Nerbonne, B.A.; Sovell, L.A.; Zimmerman, J.K.H.
2005-01-01
We synthesized nine studies that examined the influence of land use at different spatial scales in structuring biotic assemblages and stream channel characteristics in southeastern Minnesota streams. Recent studies have disagreed about the relative importance of catchment versus local characteristics in explaining variation in fish assemblages. Our synthesis indicates that both riparian- and catchment-scale land use explained significant variation in water quality, channel morphology, and fish distribution and density. Fish and macroinvertebrate assemblages can be positively affected by increasing the extent of perennial riparian and upland vegetation. Our synthesis is robust; more than 425 stream reaches were examined in an area that includes a portion of three ecoregions. Fishes ranged from coldwater to warmwater adapted. We suggest that efforts to rehabilitate stream system form and function over the long term should focus on increasing perennial vegetation in both riparian areas and uplands and on managing vegetation in large, contiguous blocks. ?? 2005 Springer Science+Business Media, Inc.
He, Monica M.
2016-01-01
The relationship between short-term macroeconomic growth and temporary mortality increases remains strongest for motor vehicle (MV) crashes. In this paper, I investigate the mechanisms that explain falling MV fatality rates during the recent Great Recession. Using U.S. state-level panel data from 2003–2013, I first estimate the relationship between unemployment and MV fatality rate and then decompose it into risk and exposure factors for different types of MV crashes. Results reveal a significant 2.9 percent decrease in MV fatality rate for each percentage point increase in unemployment rate. This relationship is almost entirely explained by changes in the risk of driving rather than exposure to the amount of driving and is particularly robust for crashes involving large commercial trucks, multiple vehicles, and speeding cars. These findings provide evidence suggesting traffic patterns directly related to economic activity lead to higher risk of MV fatality rates when the economy improves. PMID:26967529
The dynamics of mitochondrial DNA heteroplasmy: implications for human health and disease.
Stewart, James B; Chinnery, Patrick F
2015-09-01
Common genetic variants of mitochondrial DNA (mtDNA) increase the risk of developing several of the major health issues facing the western world, including neurodegenerative diseases. In this Review, we consider how these mtDNA variants arose and how they spread from their origin on one single molecule in a single cell to be present at high levels throughout a specific organ and, ultimately, to contribute to the population risk of common age-related disorders. mtDNA persists in all aerobic eukaryotes, despite a high substitution rate, clonal propagation and little evidence of recombination. Recent studies have found that de novo mtDNA mutations are suppressed in the female germ line; despite this, mtDNA heteroplasmy is remarkably common. The demonstration of a mammalian mtDNA genetic bottleneck explains how new germline variants can increase to high levels within a generation, and the ultimate fixation of less-severe mutations that escape germline selection explains how they can contribute to the risk of late-onset disorders.
Generalizing MOND to explain the missing mass in galaxy clusters
NASA Astrophysics Data System (ADS)
Hodson, Alistair O.; Zhao, Hongsheng
2017-02-01
Context. MOdified Newtonian Dynamics (MOND) is a gravitational framework designed to explain the astronomical observations in the Universe without the inclusion of particle dark matter. MOND, in its current form, cannot explain the missing mass in galaxy clusters without the inclusion of some extra mass, be it in the form of neutrinos or non-luminous baryonic matter. We investigate whether the MOND framework can be generalized to account for the missing mass in galaxy clusters by boosting gravity in high gravitational potential regions. We examine and review Extended MOND (EMOND), which was designed to increase the MOND scale acceleration in high potential regions, thereby boosting the gravity in clusters. Aims: We seek to investigate galaxy cluster mass profiles in the context of MOND with the primary aim at explaining the missing mass problem fully without the need for dark matter. Methods: Using the assumption that the clusters are in hydrostatic equilibrium, we can compute the dynamical mass of each cluster and compare the result to the predicted mass of the EMOND formalism. Results: We find that EMOND has some success in fitting some clusters, but overall has issues when trying to explain the mass deficit fully. We also investigate an empirical relation to solve the cluster problem, which is found by analysing the cluster data and is based on the MOND paradigm. We discuss the limitations in the text.
Goldstein, R.M.; Carlisle, D.M.; Meador, M.R.; Short, T.M.
2007-01-01
The environmental setting (e.g., climate, topography, geology) and land use affect stream physical characteristics singly and cumulatively. At broad geographic scales, we determined the importance of environmental setting and land use in explaining variation in stream physical characteristics. We hypothesized that as the spatial scale decreased from national to regional, land use would explain more of the variation in stream physical characteristics because environmental settings become more homogeneous. At a national scale, stepwise linear regression indicated that environmental setting was more important in explaining variability in stream physical characteristics. Although statistically discernible, the amount of variation explained by land use was not remarkable due to low partial correlations. At level II ecoregion spatial scales (southeastern USA plains, central USA plains, and a combination of the western Cordillera and the western interior basins and ranges), environmental setting variables were again more important predictors of stream physical characteristics, however, as the spatial scale decreased from national to regional, the portion of variability in stream physical characteristics explained by basin land use increased. Development of stream habitat indicators of land use will depend upon an understanding of relations between stream physical characteristics and environmental factors at multiple spatial scales. Smaller spatial scales will be necessary to reduce the confounding effects of variable environmental settings before the effects of land use can be reliably assessed. ?? Springer Science+Business Media B.V. 2006.
Response Monitoring and Adjustment: Differential Relations with Psychopathic Traits
Bresin, Konrad; Finy, M. Sima; Sprague, Jenessa; Verona, Edelyn
2014-01-01
Studies on the relation between psychopathy and cognitive functioning often show mixed results, partially because different factors of psychopathy have not been considered fully. Based on previous research, we predicted divergent results based on a two-factor model of psychopathy (interpersonal-affective traits and impulsive-antisocial traits). Specifically, we predicted that the unique variance of interpersonal-affective traits would be related to increased monitoring (i.e., error-related negativity) and adjusting to errors (i.e., post-error slowing), whereas impulsive-antisocial traits would be related to reductions in these processes. Three studies using a diverse selection of assessment tools, samples, and methods are presented to identify response monitoring correlates of the two main factors of psychopathy. In Studies 1 (undergraduates), 2 (adolescents), and 3 (offenders), interpersonal-affective traits were related to increased adjustment following errors and, in Study 3, to enhanced monitoring of errors. Impulsive-antisocial traits were not consistently related to error adjustment across the studies, although these traits were related to a deficient monitoring of errors in Study 3. The results may help explain previous mixed findings and advance implications for etiological models of psychopathy. PMID:24933282
The epidemiology of cocaine use in Spain.
Barrio Anta, G; Vicente Orta, J; Bravo Portela, M J; de la Fuente de Hoz, L
1993-12-01
Trends and patterns of cocaine use in Spain are described with the aid of different information sources such as population surveys, the State Information System on Drug Abuse, and anthropological studies. In recent years the magnitude of cocaine supply indicators has increased greatly. High levels of last-month prevalence of cocaine use have been detected among the general population--consistently higher than those for heroin-- and cocaine consumption among heroin users has increased. Although the frequency of some health problems related to cocaine use--treatment admissions, hospital emergency admissions--has increased, it is still 30 times less than for heroin. Various hypotheses to explain these discrepancies are discussed.
NASA Astrophysics Data System (ADS)
Gillespie, Jonathan; Masey, Nicola; Heal, Mathew R.; Hamilton, Scott; Beverland, Iain J.
2017-02-01
Determination of intra-urban spatial variations in air pollutant concentrations for exposure assessment requires substantial time and monitoring equipment. The objective of this study was to establish if short-duration measurements of air pollutants can be used to estimate longer-term pollutant concentrations. We compared 5-min measurements of black carbon (BC) and particle number (PN) concentrations made once per week on 5 occasions, with 4 consecutive 1-week average nitrogen dioxide (NO2) concentrations at 18 locations at a range of distances from busy roads in Glasgow, UK. 5-min BC and PN measurements (averaged over the two 5-min periods at the start and end of a week) explained 40-80%, and 7-64% respectively, of spatial variation in the intervening 1-week NO2 concentrations for individual weeks. Adjustment for variations in background concentrations increased the percentage of explained variation in the bivariate relationship between the full set of NO2 and BC measurements over the 4-week period from 28% to 50% prior to averaging of repeat measurements. The averages of five 5-min BC and PN measurements made over 5 weeks explained 75% and 33% respectively of the variation in average 1-week NO2 concentrations over the same period. The relatively high explained variation observed between BC and NO2 measured on different time scales suggests that, with appropriate steps to correct or average out temporal variations, repeated short-term measurements can be used to provide useful information on longer-term spatial patterns for these traffic-related pollutants.
Role of oxygen on the optical properties of borate glass doped with ZnO
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abdel-Baki, Manal; El-Diasty, Fouad, E-mail: fdiasty@yahoo.com
2011-10-15
Lithium tungsten borate glass (0.56-x)B{sub 2}O{sub 3}-0.4Li{sub 2}O-xZnO-0.04WO{sub 3} (0{<=}x{<=}0.1 mol%) is prepared by the melt quenching technique for photonic applications. Small relative values of ZnO are used to improve the glass optical dispersion and to probe as well the role of oxygen electronic polarizability on its optical characteristics. The spectroscopic properties of the glass are determined in a wide spectrum range (200-2500 nm) using a Fresnel-based spectrophotometric technique. Based on the Lorentz-Lorenz theory, as ZnO content increases on the expense of B{sub 2}O{sub 3} the glass molar polarizability increased due to an enhanced unshared oxide ion 2p electron density,more » which increases ionicity of the chemical bonds of glass. The role of oxide ion polarizability is explained in accordance with advanced measures and theories such as optical basicity, O 1s binding energy, the outer most cation binding energy in Yamashita-Kurosawa's interionic interaction parameter and Sun's average single bond strength. FT-IR measurements confirm an increase in bridging oxygen bonds, as a result of replacement of ZnO by B{sub 2}O{sub 3}, which increase the UV glass transmission window and transmittance. - Graphical abstract: O1s, Yamashita-Kurosawa's parameter and average single bond strength of charge overlapping between electronic shells are used to explain enhanced oxide ion 2p electron density, which increases refractive index of glasses. Highlights: > New borate glass for photonic application is prepared. > The dispersion property of the glass is effectively controlled using small amounts of ZnO. > ZnO is used to probe the glass structure and investigate the role of oxygen on the obtained optical properties of the glasses. > Modern theories are used to explain enhanced unshared oxide ion 2p electron density, which increases ionicity of chemical bonds of the glass.« less
Cederberg, C; Hedenus, F; Wirsenius, S; Sonesson, U
2013-02-01
To analyse trends in greenhouse gas (GHG) emissions from production and consumption of animal products in Sweden, life cycle emissions were calculated for the average production of pork, chicken meat, beef, dairy and eggs in 1990 and 2005. The calculated average emissions were used together with food consumption statistics and literature data on imported products to estimate trends in per capita emissions from animal food consumption. Total life cycle emissions from the Swedish livestock production were around 8.5 Mt carbon dioxide equivalents (CO2e) in 1990 and emissions decreased to 7.3 Mt CO2e in 2005 (14% reduction). Around two-thirds of the emission cut was explained by more efficient production (less GHG emission per product unit) and one-third was due to a reduced animal production. The average GHG emissions per product unit until the farm-gate were reduced by 20% for dairy, 15% for pork and 23% for chicken meat, unchanged for eggs and increased by 10% for beef. A larger share of the average beef was produced from suckler cows in cow-calf systems in 2005 due to the decreasing dairy cow herd, which explains the increased emissions for the average beef in 2005. The overall emission cuts from the livestock sector were a result of several measures taken in farm production, for example increased milk yield per cow, lowered use of synthetic nitrogen fertilisers in grasslands, reduced losses of ammonia from manure and a switch to biofuels for heating in chicken houses. In contrast to production, total GHG emissions from the Swedish consumption of animal products increased by around 22% between 1990 and 2005. This was explained by strong growth in meat consumption based mainly on imports, where growth in beef consumption especially was responsible for most emission increase over the 15-year period. Swedish GHG emissions caused by consumption of animal products reached around 1.1 t CO2e per capita in 2005. The emission cuts necessary for meeting a global temperature-increase target of 2° might imply a severe constraint on the long-term global consumption of animal food. Due to the relatively limited potential for reducing food-related emissions by higher productivity and technological means, structural changes in food consumption towards less emission-intensive food might be required for meeting the 2° target.
Joseph L. Ganey; Sean C. Kyle; Todd A. Rawlinson; Darrell L. Apprill; James P Ward
2014-01-01
Mexican Spotted Owls (Strix occidentalis lucida) are common in older forests within their range but also persist in many areas burned by wildfire and may selectively forage in these areas. One hypothesis explaining this pattern postulates that prey abundance increases in burned areas following wildfire. We observed movement to wintering areas within areas burned by...
Zhou, Qianqian; Leng, Guoyong; Feng, Leyang
2017-07-13
Understanding historical changes in flood damage and the underlying mechanisms is critical for predicting future changes for better adaptations. In this study, a detailed assessment of flood damage for 1950–1999 is conducted at the state level in the conterminous United States (CONUS). Geospatial datasets on possible influencing factors are then developed by synthesizing natural hazards, population, wealth, cropland and urban area to explore the relations with flood damage. A considerable increase in flood damage in CONUS is recorded for the study period which is well correlated with hazards. Comparably, runoff indexed hazards simulated by the Variable Infiltration Capacity (VIC) modelmore » can explain a larger portion of flood damage variations than precipitation in 84% of the states. Cropland is identified as an important factor contributing to increased flood damage in central US while urbanland exhibits positive and negative relations with total flood damage and damage per unit wealth in 20 and 16 states, respectively. Altogether, flood damage in 34 out of 48 investigated states can be predicted at the 90% confidence level. In extreme cases, ~76% of flood damage variations can be explained in some states, highlighting the potential of future flood damage prediction based on climate change and socioeconomic scenarios.« less
Population Fluctuations and Synchrony of Grassland Butterflies in Relation to Species Traits
Franzén, Markus; Nilsson, Sven G.; Johansson, Victor; Ranius, Thomas
2013-01-01
Population fluctuations and synchrony influence population persistence; species with larger fluctuations and more synchronised population fluctuations face higher extinction risks. Here, we analyse the effect of diet specialisation, mobility, length of the flight period, and distance to the northern edge of the species’ distribution in relation to between-year population fluctuations and synchrony of butterfly species. All butterfly species associated with grasslands were surveyed over five successive years at 19 grassland sites in a forest-dominated landscape (50 km2) in southern Sweden. At both the local and regional level, we found larger population fluctuations in species with longer flight periods. Population fluctuations were more synchronous among localities in diet specialists. Species with a long flight period might move more to track nectar resources compared to species with shorter flight period, and if nectar sources vary widely between years and localities it may explain that population fluctuations increase with increasing flight length. Diet generalists can use different resources (in this case host plants) at different localities and this can explain the lower synchrony in population fluctuations among generalist species. Higher degree of synchrony is one possible explanation for the higher extinction risks that have been observed for more specialised species. Therefore, diet specialists are more often threatened and require more conservation efforts than generalists. PMID:24205169
Richardson, Richard B; Harper, Mary-Ellen
2016-04-19
It has been more than 60 years since the discovery of the oxygen effect that empirically demonstrates the direct association between cell radiosensitivity and oxygen tension, important parameters in radiotherapy. Yet the mechanisms underlying this principal tenet of radiobiology are poorly understood. Better understanding of the oxygen effect may explain difficulty in eliminating hypoxic tumor cells, a major cause of regrowth after therapy. Our analysis utilizes the Howard-Flanders and Alper formula, which describes the relationship of radiosensitivity with oxygen tension. Here, we assign and qualitatively assess the relative contributions of two important mechanisms. The first mechanism involves the emission of reactive oxygen species from the mitochondrial electron transport chain, which increases with oxygen tension. The second mechanism is related to an energy and repair deficit, which increases with hypoxia. Following a radiation exposure, the uncoupling of the oxidative phosphorylation system (proton leak) in mitochondria lowers the emission of reactive oxygen species which has implications for fractionated radiotherapy, particularly of hypoxic tumors. Our analysis shows that, in oxygenated tumor and normal cells, mitochondria, rather than the nucleus, are the primary loci of radiotherapy effects, especially for low linear energy transfer radiation. Therefore, the oxygen effect can be explained by radiation-induced effects in mitochondria that generate reactive oxygen species, which in turn indirectly target nuclear DNA.
Status threat, not economic hardship, explains the 2016 presidential vote
2018-01-01
This study evaluates evidence pertaining to popular narratives explaining the American public’s support for Donald J. Trump in the 2016 presidential election. First, using unique representative probability samples of the American public, tracking the same individuals from 2012 to 2016, I examine the “left behind” thesis (that is, the theory that those who lost jobs or experienced stagnant wages due to the loss of manufacturing jobs punished the incumbent party for their economic misfortunes). Second, I consider the possibility that status threat felt by the dwindling proportion of traditionally high-status Americans (i.e., whites, Christians, and men) as well as by those who perceive America’s global dominance as threatened combined to increase support for the candidate who emphasized reestablishing status hierarchies of the past. Results do not support an interpretation of the election based on pocketbook economic concerns. Instead, the shorter relative distance of people’s own views from the Republican candidate on trade and China corresponded to greater mass support for Trump in 2016 relative to Mitt Romney in 2012. Candidate preferences in 2016 reflected increasing anxiety among high-status groups rather than complaints about past treatment among low-status groups. Both growing domestic racial diversity and globalization contributed to a sense that white Americans are under siege by these engines of change. PMID:29686081
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Qianqian; Leng, Guoyong; Feng, Leyang
Understanding historical changes in flood damage and the underlying mechanisms is critical for predicting future changes for better adaptations. In this study, a detailed assessment of flood damage for 1950–1999 is conducted at the state level in the conterminous United States (CONUS). Geospatial datasets on possible influencing factors are then developed by synthesizing natural hazards, population, wealth, cropland and urban area to explore the relations with flood damage. A considerable increase in flood damage in CONUS is recorded for the study period which is well correlated with hazards. Comparably, runoff indexed hazards simulated by the Variable Infiltration Capacity (VIC) modelmore » can explain a larger portion of flood damage variations than precipitation in 84% of the states. Cropland is identified as an important factor contributing to increased flood damage in central US while urbanland exhibits positive and negative relations with total flood damage and damage per unit wealth in 20 and 16 states, respectively. Altogether, flood damage in 34 out of 48 investigated states can be predicted at the 90% confidence level. In extreme cases, ~76% of flood damage variations can be explained in some states, highlighting the potential of future flood damage prediction based on climate change and socioeconomic scenarios.« less
A Biophysical Model for the Staircase Geometry of Stereocilia
Orly, Gilad; Manor, Uri; Gov, Nir S.
2015-01-01
Cochlear hair cell bundles, made up of 10s to 100s of individual stereocilia, are essential for hearing, and even relatively minor structural changes, due to mutations or injuries, can result in total deafness. Consistent with its specialized role, the staircase geometry (SCG) of hair cell bundles presents one of the most striking, intricate, and precise organizations of actin-based cellular shapes. Composed of rows of actin-filled stereocilia with increasing lengths, the hair cell’s staircase-shaped bundle is formed from a progenitor field of smaller, thinner, and uniformly spaced microvilli with relatively invariant lengths. While recent genetic studies have provided a significant increase in information on the multitude of stereocilia protein components, there is currently no model that integrates the basic physical forces and biochemical processes necessary to explain the emergence of the SCG. We propose such a model derived from the biophysical and biochemical characteristics of actin-based protrusions. We demonstrate that polarization of the cell’s apical surface, due to the lateral polarization of the entire epithelial layer, plays a key role in promoting SCG formation. Furthermore, our model explains many distinct features of the manifestations of SCG in different species and in the presence of various deafness-associated mutations. PMID:26207893
Changes in urban-related precipitation in the summer over three city clusters in China
NASA Astrophysics Data System (ADS)
Zhao, Deming; Wu, Jian
2017-09-01
The impacts of urban surface expansion on the summer precipitations over three city clusters [Beijing-Tianjin-Hebei (BTH), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD)] in eastern China under different monsoonal circulation backgrounds were explored using the nested fifth-generation Penn State/NCAR Mesoscale Model version 3.7 (MM5 V3.7), including the urban-related thermal and dynamical parameters. Ten-year integrations were performed using satellite image data from 2000 and 2010 to represent the urban surface distributions and expansions in China. Changes in the precipitation revealed obvious subregional characteristics, which could be explained by the influences of the vertical wind velocity and moisture flux. With urban-related warming, vertical wind motion generally intensified over urban surface-expanded areas. Meanwhile, the increase in impervious surface areas induced rapid rainwater runoff into drains, and the Bowen ratio increased over urban areas, which further contributed to changes in the local moisture fluxes in these regions. The intensities of the changes in precipitation were inconsistent over the three city clusters, although the changes in vertical motion and local evaporation were similar, which indicates that the changes in precipitation cannot be solely explained by the changes in the local evaporation-related moisture flux. The changes in precipitation were also influenced by the changes in the East Asian summer monsoon (EASM) circulation and the corresponding moisture flux, which are expressed in marked subregional characteristics. Therefore, the influence of urban-related precipitation over the three city clusters in China, for which changes in moisture flux from both the impacted local evaporation and EASM circulation should be considered, varied based on the precipitation changes of only a single city.
Kirsten, Holger; Al-Hasani, Hoor; Holdt, Lesca; Gross, Arnd; Beutner, Frank; Krohn, Knut; Horn, Katrin; Ahnert, Peter; Burkhardt, Ralph; Reiche, Kristin; Hackermüller, Jörg; Löffler, Markus; Teupser, Daniel; Thiery, Joachim; Scholz, Markus
2015-01-01
Genetics of gene expression (eQTLs or expression QTLs) has proved an indispensable tool for understanding biological pathways and pathomechanisms of trait-associated SNPs. However, power of most genome-wide eQTL studies is still limited. We performed a large eQTL study in peripheral blood mononuclear cells of 2112 individuals increasing the power to detect trans-effects genome-wide. Going beyond univariate SNP-transcript associations, we analyse relations of eQTLs to biological pathways, polygenetic effects of expression regulation, trans-clusters and enrichment of co-localized functional elements. We found eQTLs for about 85% of analysed genes, and 18% of genes were trans-regulated. Local eSNPs were enriched up to a distance of 5 Mb to the transcript challenging typically implemented ranges of cis-regulations. Pathway enrichment within regulated genes of GWAS-related eSNPs supported functional relevance of identified eQTLs. We demonstrate that nearest genes of GWAS-SNPs might frequently be misleading functional candidates. We identified novel trans-clusters of potential functional relevance for GWAS-SNPs of several phenotypes including obesity-related traits, HDL-cholesterol levels and haematological phenotypes. We used chromatin immunoprecipitation data for demonstrating biological effects. Yet, we show for strongly heritable transcripts that still little trans-chromosomal heritability is explained by all identified trans-eSNPs; however, our data suggest that most cis-heritability of these transcripts seems explained. Dissection of co-localized functional elements indicated a prominent role of SNPs in loci of pseudogenes and non-coding RNAs for the regulation of coding genes. In summary, our study substantially increases the catalogue of human eQTLs and improves our understanding of the complex genetic regulation of gene expression, pathways and disease-related processes. PMID:26019233
Comparable Rest-related Promotion of Spatial Memory Consolidation in Younger and Older Adults
Craig, Michael; Wolbers, Thomas; Harris, Mathew A.; Hauff, Patrick; Della Sala, Sergio; Dewar, Michaela
2017-01-01
Flexible spatial navigation depends on cognitive mapping, a function that declines with increasing age. In young adults, a brief period of post-navigation rest promotes the consolidation/integration of spatial memories into accurate cognitive maps. We examined (1) whether rest promotes spatial memory consolidation/integration in older adults and (2) whether the magnitude of the rest benefit changes with increasing age. Young and older adults learned a route through a virtual environment, followed by a 10min delay comprising either wakeful rest or a perceptual task, and a subsequent cognitive mapping task, requiring the pointing to landmarks from different locations. Pointing accuracy was lower in the older than younger adults. However, there was a comparable rest-related enhancement in pointing accuracy in the two age groups. Together our findings suggest that (i) the age-related decline in cognitive mapping cannot be explained by increased consolidation interference in older adults, and (ii) as we grow older rest continues to support the consolidation/integration of spatial memories. PMID:27689512
Beison, Ashley; Rademacher, David J.
2017-01-01
Background and aims Smartphones are ubiquitous. As smartphones increased in popularity, researchers realized that people were becoming dependent on their smartphones. The purpose here was to provide a better understanding of the factors related to problematic smartphone use (PSPU). Methods The participants were 100 undergraduates (25 males, 75 females) whose ages ranged from 18 to 23 (mean age = 20 years). The participants completed questionnaires to assess gender, ethnicity, year in college, father’s education level, mother’s education level, family income, age, family history of alcoholism, and PSPU. The Family Tree Questionnaire assessed family history of alcoholism. The Mobile Phone Problem Use Scale (MPPUS) and the Adapted Cell Phone Addiction Test (ACPAT) were used to determine the degree of PSPU. Whereas the MPPUS measures tolerance, escape from other problems, withdrawal, craving, and negative life consequences, the ACPAT measures preoccupation (salience), excessive use, neglecting work, anticipation, lack of control, and neglecting social life. Results Family history of alcoholism and father’s education level together explained 26% of the variance in the MPPUS scores and 25% of the variance in the ACPAT scores. The inclusion of mother’s education level, ethnicity, family income, age, year in college, and gender did not significantly increase the proportion of variance explained for either MPPUS or ACPAT scores. Discussion and conclusions Family history of alcoholism and father’s education level are good predictors of PSPU. As 74%–75% of the variance in PSPU scale scores was not explained, future studies should aim to explain this variance. PMID:28316252
Gornish, Elise S; Miller, Thomas E
2015-01-01
Increasing rates of change in climate have been observed across the planet and have contributed to the ongoing range shifts observed for many species. Although ecologists are now using a variety of approaches to study how much and through what mechanisms increasing temperature and nutrient pollution may influence the invasions inherent in range shifts, accurate predictions are still lacking. In this study, we conducted a factorial experiment, simultaneously manipulating warming, nitrogen addition and introduction of Pityopsis aspera, to determine how range-shifting species affect a plant community. We quantified the resident community using ordination scores, then used structural equation modeling to examine hypotheses related to how plants respond to a network of experimental treatments and environmental variables. Variation in soil pH explained plant community response to nitrogen addition in the absence of invasion. However, in the presence of invasion, the direct effect of nitrogen on the community was negligible and soil moisture was important for explaining nitrogen effects. We did not find effects of warming on the native plant community in the absence of invasion. In the presence of invasion, however, warming had negative effects on functional richness directly and invasion and herbivory explained the overall positive effect of warming on the plant community. This work highlights the variation in the biotic and abiotic factors responsible for explaining independent and collective climate change effects over a short time scale. Future work should consider the complex and non-additive relationships among factors of climate change and invasion in order to capture more ecologically relevant features of our changing environment.
The influence of El Niño-Southern Oscillation on boreal winter rainfall over Peninsular Malaysia
NASA Astrophysics Data System (ADS)
Richard, Sandra; Walsh, Kevin J. E.
2017-09-01
Multi-scale interactions between El Niño-Southern Oscillation and the Boreal Winter Monsoon contribute to rainfall variations over Malaysia. Understanding the physical mechanisms that control these spatial variations in local rainfall is crucial for improving weather and climate prediction and related risk management. Analysis using station observations and European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim) reanalysis reveals a significant decrease in rainfall during El Niño (EL) and corresponding increase during La Niña particularly north of 2°N over Peninsular Malaysia (PM). It is noted that the southern tip of PM shows a small increase in rainfall during El Niño although not significant. Analysis of the diurnal cycle of rainfall and winds indicates that there are no significant changes in morning and evening rainfall over PM that could explain the north-south disparity. Thus, we suggest that the key factor which might explain the north-south rainfall disparity is the moisture flux convergence (MFC). During the December to January (DJF) period of EL years, except for the southern tip of PM, significant negative MFC causes drying as well as suppression of uplift over most areas. In addition, lower specific humidity combined with moisture flux divergence results in less moisture over PM. Thus, over the areas north of 2°N, less rainfall (less heavy rain days) with smaller diurnal rainfall amplitude explains the negative rainfall anomaly observed during DJF of EL. The same MFC argument might explain the dipolar pattern over other areas such as Borneo if further analysis is performed.
Predicting nitrogen and acidity effects on long-term dynamics of dissolved organic matter.
Rowe, E C; Tipping, E; Posch, M; Oulehle, F; Cooper, D M; Jones, T G; Burden, A; Hall, J; Evans, C D
2014-01-01
Increases in dissolved organic carbon (DOC) fluxes may relate to changes in sulphur and nitrogen pollution. We integrated existing models of vegetation growth and soil organic matter turnover, acid-base dynamics, and organic matter mobility, to form the 'MADOC' model. After calibrating parameters governing interactions between pH and DOC dissolution using control treatments on two field experiments, MADOC reproduced responses of pH and DOC to additions of acidifying and alkalising solutions. Long-term trends in a range of acid waters were also reproduced. The model suggests that the sustained nature of observed DOC increases can best be explained by a continuously replenishing potentially-dissolved carbon pool, rather than dissolution of a large accumulated store. The simulations informed the development of hypotheses that: DOC increase is related to plant productivity increase as well as to pH change; DOC increases due to nitrogen pollution will become evident, and be sustained, after soil pH has stabilised. Copyright © 2013 Elsevier Ltd. All rights reserved.
Zooplankton seasonality across a latitudinal gradient in the Northeast Atlantic Shelves Province
NASA Astrophysics Data System (ADS)
Fanjul, Alvaro; Iriarte, Arantza; Villate, Fernando; Uriarte, Ibon; Atkinson, Angus; Cook, Kathryn
2018-05-01
Zooplankton seasonality and its environmental drivers were studied at four coastal sites within the Northeast Atlantic Shelves Province (Bilbao35 (B35) and Urdaibai35 (U35) in the Bay of Biscay, Plymouth L4 (L4) in the English Channel and Stonehaven (SH) in the North Sea) using time series spanning 1999-2013. Seasonal community patterns were extracted at the level of broad zooplankton groups and copepod and cladoceran genera using redundancy analysis. Temperature was generally the environmental factor that explained most of the taxa seasonal variations at the four sites. However, between-site differences related to latitude and trophic status (i.e. from oligotrophic to mesotrophic) were observed in the seasonality of zooplankton community, mainly in the pattern of taxa that peaked in spring-summer as opposed to late autumn-winter zooplankton, which were linked primarily to differences in the seasonal pattern of phytoplankton. The percentage of taxa variations explained by environmental factors increased with latitude and trophic status likely related to the increase in the co-variation of temperature and chlorophyll a, as well as in the increase in regularity of the seasonal patterns of both temperature and chlorophyll a from south to north, and of chlorophyll a with trophic status. Cladocerans and cirripede larvae at B35 and U35, echinoderm larvae at L4 and decapod larvae at SH made the highest contribution to shape the main mode of seasonal pattern of zooplankton community, which showed a seasonal delay with latitude, as well as with the increase in trophic status.
Spatial patterns of large natural fires in Sierra Nevada wilderness areas
Collins, B.M.; Kelly, M.; van Wagtendonk, J.W.; Stephens, S.L.
2007-01-01
The effects of fire on vegetation vary based on the properties and amount of existing biomass (or fuel) in a forest stand, weather conditions, and topography. Identifying controls over the spatial patterning of fire-induced vegetation change, or fire severity, is critical in understanding fire as a landscape scale process. We use gridded estimates of fire severity, derived from Landsat ETM+ imagery, to identify the biotic and abiotic factors contributing to the observed spatial patterns of fire severity in two large natural fires. Regression tree analysis indicates the importance of weather, topography, and vegetation variables in explaining fire severity patterns between the two fires. Relative humidity explained the highest proportion of total sum of squares throughout the Hoover fire (Yosemite National Park, 2001). The lowest fire severity corresponded with increased relative humidity. For the Williams fire (Sequoia/Kings Canyon National Parks, 2003) dominant vegetation type explains the highest proportion of sum of squares. Dominant vegetation was also important in determining fire severity throughout the Hoover fire. In both fires, forest stands that were dominated by lodgepole pine (Pinus contorta) burned at highest severity, while red fir (Abies magnifica) stands corresponded with the lowest fire severities. There was evidence in both fires that lower wind speed corresponded with higher fire severity, although the highest fire severity in the Williams fire occurred during increased wind speed. Additionally, in the vegetation types that were associated with lower severity, burn severity was lowest when the time since last fire was fewer than 11 and 17 years for the Williams and Hoover fires, respectively. Based on the factors and patterns identified, managers can anticipate the effects of management ignited and naturally ignited fires at the forest stand and the landscape levels. ?? 2007 Springer Science+Business Media, Inc.
Estimation of Particulate Mass and Manganese Exposure Levels among Welders
Hobson, Angela; Seixas, Noah; Sterling, David; Racette, Brad A.
2011-01-01
Background: Welders are frequently exposed to Manganese (Mn), which may increase the risk of neurological impairment. Historical exposure estimates for welding-exposed workers are needed for epidemiological studies evaluating the relationship between welding and neurological or other health outcomes. The objective of this study was to develop and validate a multivariate model to estimate quantitative levels of welding fume exposures based on welding particulate mass and Mn concentrations reported in the published literature. Methods: Articles that described welding particulate and Mn exposures during field welding activities were identified through a comprehensive literature search. Summary measures of exposure and related determinants such as year of sampling, welding process performed, type of ventilation used, degree of enclosure, base metal, and location of sampling filter were extracted from each article. The natural log of the reported arithmetic mean exposure level was used as the dependent variable in model building, while the independent variables included the exposure determinants. Cross-validation was performed to aid in model selection and to evaluate the generalizability of the models. Results: A total of 33 particulate and 27 Mn means were included in the regression analysis. The final model explained 76% of the variability in the mean exposures and included welding process and degree of enclosure as predictors. There was very little change in the explained variability and root mean squared error between the final model and its cross-validation model indicating the final model is robust given the available data. Conclusions: This model may be improved with more detailed exposure determinants; however, the relatively large amount of variance explained by the final model along with the positive generalizability results of the cross-validation increases the confidence that the estimates derived from this model can be used for estimating welder exposures in absence of individual measurement data. PMID:20870928
Saloner, Brendan; Carson, Nicholas; Lê Cook, Benjamin
2014-06-01
To identify contributors to racial/ethnic differences in completion of alcohol and marijuana treatment among adolescents at publicly funded providers. The 2007 Treatment Episode Data Set provided substance use history, treatment setting, and treatment outcomes for youth aged 12-17 years from five racial/ethnic groups (N = 67,060). Individual-level records were linked to variables measuring the social context and service system characteristics of the metropolitan area. We implemented nonlinear regression decomposition to identify variables that explained minority-white differences. Black and Hispanic youth were significantly less likely than whites to complete treatment for both alcohol and marijuana. Completion rates were similar for whites, Native Americans, and Asian-Americans, however. Differences in predictor variables explained 12.7% of the black-white alcohol treatment gap and 7.6% of the marijuana treatment gap. In contrast, predictors explained 57.4% of the Hispanic-white alcohol treatment gap and 19.8% of the marijuana treatment gap. While differences in the distribution of individual-level variables explained little of the completion gaps, metropolitan-level variables substantially contributed to Hispanic-white gaps. For example, racial/ethnic composition of the metropolitan area explained 41.0% of the Hispanic-white alcohol completion gap and 23.2% of the marijuana completion gap. Regional differences in addiction treatment financing (particularly use of Medicaid funding) explained 13.7% of the Hispanic-white alcohol completion gap and 9.8% of the Hispanic-white marijuana treatment completion gap. Factors related to social context are likely to be important contributors to white-minority differences in addiction treatment completion, particularly for Hispanic youth. Increased Medicaid funding, coupled with culturally tailored services, could be particularly beneficial. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Lagares, Alfonso; Jiménez-Roldán, Luis; Gomez, Pedro A; Munarriz, Pablo M; Castaño-León, Ana M; Cepeda, Santiago; Alén, José F
2015-12-01
Quantitative estimation of the hemorrhage volume associated with aneurysm rupture is a new tool of assessing prognosis. To determine the prognostic value of the quantitative estimation of the amount of bleeding after aneurysmal subarachnoid hemorrhage, as well the relative importance of this factor related to other prognostic indicators, and to establish a possible cut-off value of volume of bleeding related to poor outcome. A prospective cohort of 206 patients consecutively admitted with the diagnosis of aneurysmal subarachnoid hemorrhage to Hospital 12 de Octubre were included in the study. Subarachnoid, intraventricular, intracerebral, and total bleeding volumes were calculated using analytic software. For assessing factors related to prognosis, univariate and multivariate analysis (logistic regression) were performed. The relative importance of factors in determining prognosis was established by calculating their proportion of explained variation. Maximum Youden index was calculated to determine the optimal cut point for subarachnoid and total bleeding volume. Variables independently related to prognosis were clinical grade at admission, age, and the different bleeding volumes. The proportion of variance explained is higher for subarachnoid bleeding. The optimal cut point related to poor prognosis is a volume of 20 mL both for subarachnoid and total bleeding. Volumetric measurement of subarachnoid or total bleeding volume are both independent prognostic factors in patients with aneurysmal subarachnoid hemorrhage. A volume of more than 20 mL of blood in the initial noncontrast computed tomography is related to a clear increase in poor outcome risk. : aSAH, aneurysmal subarachnoid hemorrhage.
Reid, Rachel O; Deb, Partha; Howell, Benjamin L; Conway, Patrick H; Shrank, William H
2016-02-01
To facilitate informed decision-making in the Medicare Advantage marketplace, the Centers for Medicare & Medicaid Services publishes plan information on the Medicare Plan Finder website, including costs, benefits, and star ratings reflecting quality. Little is known about how beneficiaries weigh costs versus quality in enrollment decisions. We aimed to assess associations between publicly reported Medicare Advantage plan attributes (i.e., costs, quality, and benefits) and brand market share and beneficiaries' enrollment decisions. We performed a nationwide, beneficiary-level cross-sectional analysis of 847,069 beneficiaries enrolling in Medicare Advantage for the first time in 2011. Matching beneficiaries with their plan choice sets, we used conditional logistic regression to estimate associations between plan attributes and enrollment to assess the proportion of enrollment variation explained by plan attributes and willingness to pay for quality. Relative to the total variation explained by the model, the variation in plan choice explained by premiums (25.7 %) and out-of-pocket costs (11.6 %) together explained nearly three times as much as quality ratings (13.6 %), but brand market share explained the most variation (35.3 %). Further, while beneficiaries were willing to pay more in total annual combined premiums and out-of-pocket costs for higher-rated plans (from $4,154.93 for 2.5-star plans to $5,698.66 for 5-star plans), increases in willingness to pay diminished at higher ratings, from $549.27 (95 %CI: $541.10, $557.44) for a rating increase from 2.5 to 3 stars to $68.22 (95 %CI: $61.44, $75.01) for an increase from 4.5 to 5 stars. Willingness to pay varied among subgroups: beneficiaries aged 64-65 years were more willing to pay for higher-rated plans, while black and rural beneficiaries were less willing to pay for higher-rated plans. While beneficiaries prefer higher-quality and lower-cost Medicare Advantage plans, marginal utility for quality diminishes at higher star ratings, and their decisions are strongly associated with plans' brand market share.
Actual change and inaccurate recall contribute to posttraumatic growth following radiotherapy.
Ransom, Sean; Sheldon, Kennon M; Jacobsen, Paul B
2008-10-01
People with cancer often report that they experience personal growth as a result of the disease, but such reports have unclear validity. Some suggest such growth results from Rogers's (1951) hypothesized organismic valuing process (OVP), an innate tendency for people to gravitate toward well-being; others suggest this growth may be a positive illusion resulting from temporal self-comparisons. To test these conceptualizations, the authors examined 83 individuals with Stages 0-III breast or prostate cancer. Patients completed measures of positive attributes and personal life goals before radiotherapy (Time 1) and after radiotherapy (Time 2). At Time 2, participants also attempted to recreate their Time 1 responses and completed a posttraumatic growth (PTG) measure. PTG was significantly related with actual increases (but not perceived increases) in the relative importance of intrinsic goals versus extrinsic goals and with perceived increases (but not actual increases) in positive attributes. These measures were unrelated to one another and thus explained unique variance in PTG. Data suggest that both actual change processes related to the OVP and biases in autobiographic recall may independently contribute to PTG reports. (c) 2008 APA, all rights reserved.
Exercising self-control increases relative left frontal cortical activation.
Schmeichel, Brandon J; Crowell, Adrienne; Harmon-Jones, Eddie
2016-02-01
Self-control refers to the capacity to override or alter a predominant response tendency. The current experiment tested the hypothesis that exercising self-control temporarily increases approach motivation, as revealed by patterns of electrical activity in the prefrontal cortex. Participants completed a writing task that did vs did not require them to exercise self-control. Then they viewed pictures known to evoke positive, negative or neutral affect. We assessed electroencephalographic (EEG) activity while participants viewed the pictures, and participants reported their trait levels of behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivity at the end of the study. We found that exercising (vs not exercising) self-control increased relative left frontal cortical activity during picture viewing, particularly among individuals with relatively higher BAS than BIS, and particularly during positive picture viewing. A similar but weaker pattern emerged during negative picture viewing. The results suggest that exercising self-control temporarily increases approach motivation, which may help to explain the aftereffects of self-control (i.e. ego depletion). © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Nesting bird "host funnel" increases mosquito-bird contact rate.
Caillouët, Kevin A; Riggan, Anna E; Bulluck, Lesley P; Carlson, John C; Sabo, Roy T
2013-03-01
Increases in vector-host contact rates can enhance arbovirus transmission intensity. We investigated weekly fluctuations in contact rates between mosquitoes and nesting birds using the recently described Nest Mosquito Trap (NMT). The number of mosquitoes per nestling increased from < 1 mosquito per trap night to 36.2 in the final 2 wk of the nesting season. Our evidence suggests the coincidence of the end of the avian nesting season and increasing mosquito abundances may have caused a "host funnel," concentrating host-seeking mosquitoes to the few remaining nestlings. The relative abundance of mosquitoes collected by the NMT suggests that significantly more Aedes albopictus (Skuse) and Culex pipiens (L.) /restuans (Theobald) sought nesting bird bloodmeals than were predicted by their relative abundances in CO2-baited Centers for Disease Control and Prevention light and gravid traps. Culex salinarius (Coquillett) and Culex erraticus Dyar and Knab were collected in NMTs in proportion to their relative abundances in the generic traps. Temporal host funnels and nesting bird host specificity may enhance arbovirus amplification and explain observed West Nile virus and St. Louis encephalitis virus amplification periods.
Heins, Marianne J; Knoop, Hans; Burk, William J; Bleijenberg, Gijs
2013-09-01
Cognitive behaviour therapy (CBT) can significantly reduce fatigue in chronic fatigue syndrome (CFS), but little is known about the process of change taking place during CBT. Based on a recent treatment model (Wiborg et al. J Psych Res 2012), we examined how (changes in) cognitions and behaviour are related to the decrease in fatigue. We included 183 patients meeting the US Centers for Disease Control criteria for CFS, aged 18 to 65 years, starting CBT. We measured fatigue and possible process variables before treatment; after 6, 12 and 18 weeks; and after treatment. Possible process variables were sense of control over fatigue, focusing on symptoms, self-reported physical functioning, perceived physical activity and objective (actigraphic) physical activity. We built multiple regression models, explaining levels of fatigue during therapy by (changes in) proposed process variables. We observed large individual variation in the patterns of change in fatigue and process variables during CBT for CFS. Increases in the sense of control over fatigue, perceived activity and self-reported physical functioning, and decreases in focusing on symptoms explained 20 to 46% of the variance in fatigue. An increase in objective activity was not a process variable. A change in cognitive factors seems to be related to the decrease in fatigue during CBT for CFS. The pattern of change varies considerably between patients, but changes in process variables and fatigue occur mostly in the same period. © 2013.
Schoormans, Dounya; Czene, Kamila; Hall, Per; Brandberg, Yvonne
2015-05-01
The objective of this study was: 1) to compare health-related quality of life (HRQoL) scores of breast cancer survivors to matched controls; and 2) to examine the relative impact (explained variance) of the type and number of co-morbidities on HRQoL. Data from the KARMA project was used in this cross-sectional study. For each woman diagnosed with breast cancer (n = 2552) there were two healthy age- and geographically matched females (n = 5104). Breast cancer survivors were categorized according to time since diagnosis: recently diagnosed (0-1 year), short- (2-5 years), mid- (6-10 years), and long-term survivors (> 10 years). Women completed a questionnaire addressing demographics (age, educational level, and geographical location), lifestyle factors (body mass index (BMI) and smoking), co-morbidities, and HRQoL. The difference in explained variance in six HRQoL-domains between demographics, lifestyle factors, and co-morbidity in women with breast cancer and matched controls was examined by hierarchical regression analyses. Women recently diagnosed (n = 63), reported the worst HRQoL followed by short-term survivors (2-5 years, n = 863). Thereafter, HRQoL scores further improved (6-10 years, n = 726), and were comparable to healthy females after 10 years (n = 893). Co-morbidity has a negative impact on HRQoL, which increased with time after diagnosis. Cardiovascular disease and depression were the strongest associates. Breast cancer survivors report clinically significant improvement in HRQoL scores six years after diagnosis. Co-morbidity has a negative impact on HRQoL, which increases with time after diagnosis, even though the number of co-morbidities remains stable. In long-term survivors there should be increasing awareness of co-morbidity and its impact on HRQoL.
Held, Philip; Owens, Gina P; Monroe, J Richard; Chard, Kathleen M
2017-08-01
The present study examined the predictive role of increased self-reported mindfulness skills on reduced trauma-related guilt in a sample of veterans over the course of residential treatment for posttraumatic stress disorder (PTSD; N = 128). The residential treatment consisted of seven weeks of intensive cognitive processing therapy (CPT) for PTSD, as well as additional psychoeducational groups, including seven sessions on mindfulness skills. Increased mindfulness skills describing, acting with awareness, and accepting without judgment were significantly associated with reductions in trauma-related guilt over the course of treatment. Increases in the ability to act with awareness and accept without judgment were significantly associated with reductions in global guilt, R 2 = .26, guilt distress, R 2 = .23, guilt cognitions, R 2 = .23, and lack of justification, R 2 = .11. An increase in the ability to accept without judgment was the only self-reported mindfulness skill that was associated with reductions in hindsight bias, β = -.34 and wrongdoing, β = -.44. Increases in self-reported mindfulness skills explained 15.1 to 24.1% of the variance in reductions in trauma-related guilt, suggesting that mindfulness skills may play a key role in reducing the experience of trauma-related guilt during psychotherapy. Our results provide preliminary support for the use of mindfulness groups as an adjunct to traditional evidence-based treatments aimed at reducing trauma-related guilt, though this claim needs to be tested further using experimental designs. Copyright © 2017 International Society for Traumatic Stress Studies.
Jenkins, Marion W; Cairncross, Sandy
2010-03-01
Latrine diffusion patterns across 502 villages in Benin, West Africa, were analysed to explore factors driving initial and increasing levels of household adoption in low-coverage rural areas of sub-Saharan Africa. Variables explaining adoption related to population density, size, infrastructure/services, non-agricultural occupations, road and urban proximity, and the nearby latrine adoption rate, capturing differences in the physical and social environment, lifestyles and latrine exposure involved in stimulating status/prestige and well-being reasons for latrine adoption. Contagion was most important in explaining adoption initiation. Cluster analysis revealed four distinct village typologies of demand for latrines which provide a framework for tailoring promotional interventions to better match the different sanitation demand characteristics of communities in scaling-up sanitation development and promotion programmes.
Heat flow and thermotectonic problems of the central Ventura Basin, southern California
De Rito, R. F.; Lachenbruch, A.H.; Moses, T.H.; Munroe, R.J.
1989-01-01
The Ventura Basin, southern California, is located near the Big Bend area of the San Andreas fault system, within the Transverse Ranges physiographic province. Negative curvature of the Ventura Avenue temperature profiles may be explained by an increase in thermal conductivity associated with tectonic compaction of the underlying Pliocene clastic sequence. Basinwide, heat flow averages about 48 mW/m2, a value which is low relative to most of southern California. As heat flow does not vary systematically to the maximum measured depth of about 4 km, this anomly is not easily explained in terms of hydrologic effects or recent uplift and erosion. However, a diminution of heat flow is an expectable consequence of the accumulation of cold sediments (up to 12 km) since Eocene time. -from Authors
Bohlmann, Clarissa; Rauch, Andreas; Zacher, Hannes
2017-01-01
Researchers and practitioners are increasingly interested in entrepreneurship as a means to fight youth unemployment and to improve financial stability at higher ages. However, only few studies so far have examined the association between age and entrepreneurial activity. Based on theories from the lifespan psychology literature and entrepreneurship, we develop and test a model in which perceived opportunities and skills explain the relationship between age and entrepreneurial activity. We analyzed data from the 2013 Global Entrepreneurship Monitor (GEM), while controlling for gender and potential variation between countries. Results showed that age related negatively to entrepreneurial activity, and that perceived opportunities and skills for entrepreneurship mediated this relationship. Overall, these findings suggest that entrepreneurship research should treat age as a substantial variable.
Bohlmann, Clarissa; Rauch, Andreas; Zacher, Hannes
2017-01-01
Researchers and practitioners are increasingly interested in entrepreneurship as a means to fight youth unemployment and to improve financial stability at higher ages. However, only few studies so far have examined the association between age and entrepreneurial activity. Based on theories from the lifespan psychology literature and entrepreneurship, we develop and test a model in which perceived opportunities and skills explain the relationship between age and entrepreneurial activity. We analyzed data from the 2013 Global Entrepreneurship Monitor (GEM), while controlling for gender and potential variation between countries. Results showed that age related negatively to entrepreneurial activity, and that perceived opportunities and skills for entrepreneurship mediated this relationship. Overall, these findings suggest that entrepreneurship research should treat age as a substantial variable. PMID:29250004
The influence of labor market changes on first-time medical school applicant pools.
Cort, David A; Morrison, Emory
2014-12-01
To explore whether the number and composition of first-time applicants to U.S. MD-granting medical schools, which have fluctuated over the past 30 years, are related to changes in labor market strength, specifically the unemployment rate and wages. The authors merged time series data from 1980 through 2010 (inclusive) from five sources and used multivariate time series models to determine whether changes in labor market strength (and several other macro-level factors) were related to the number of the medical school applicants as reported by the American Medical College Application Service. Analyses were replicated across specific sex and race/ethnicity applicant pools. Two results surfaced in the analyses. First, the strength of the labor market was not influential in explaining changes in applicant pool sizes for all applicants, but was strongly influential in explaining changes for black and Hispanic males. Increases of $1,000 in prevailing median wages produced a 1.6% decrease in the white male applicant pool, while 1% increases in the unemployment rate were associated with 4.5% and 3.1% increases in, respectively, the black and Hispanic male applicant pools. Second, labor market strength was a more important determinant in applications from males than in applications from females. Although stakeholders cannot directly influence the overall economic market, they can plan and prepare for fewer applications from males, especially those who are black and Hispanic, when the labor market is strong.
Egg size variation among tropical and temperate songbirds: An embryonic temperature hypothesis
Martin, T.E.
2008-01-01
Species with 'slow' life history strategies (long life, low fecundity) are thought to produce high-quality offspring by investing in larger, but fewer, young. Larger eggs are indeed associated with fewer eggs across taxa and can yield higher-quality offspring. Tropical passerines appear to follow theory because they commonly exhibit slow life history strategies and produce larger, but fewer, eggs compared with northern species. Yet, I show here that relative egg mass (corrected for adult mass) varies extensively in the tropics and subtropics for the same clutch size, and this variation is unexplained. I propose a hypothesis to explain egg size variation both within the tropics and between latitudes: Relative egg mass increases in species with cooler egg temperatures and longer embryonic periods to offset associated increases in energetic requirements of embryos. Egg temperatures of birds are determined by parental incubation behavior and are often cooler among tropical passerines because of reduced parental attentiveness of eggs. Here, I show that cooler egg temperatures and longer embryonic periods explained the enigmatic variation in egg mass within and among regions, based on field studies in tropical Venezuela (36 species), subtropical Argentina (16 species), and north temperate Arizona (20 species). Alternative explanations are not supported. Thus, large egg sizes may reflect compensation for increased energetic requirements of cool egg temperatures and long embryonic periods that result from reduced parental attentiveness in tropical birds. ?? 2008 by The National Academy of Sciences of the USA.
Increased neural responses to empathy for pain might explain how acute stress increases prosociality
Tomova, L.; Majdandžić, J.; Hummer, A.; Windischberger, C.; Heinrichs, M.
2017-01-01
Abstract Recent behavioral investigations suggest that acute stress can increase prosocial behavior. Here, we investigated whether increased empathy represents a potential mechanism for this finding. Using functional magnetic resonance imaging, we assessed the effects of acute stress on neural responses related to automatic and regulatory components of empathy for pain as well as subsequent prosocial behavior. Stress increased activation in brain areas associated with the automatic sharing of others’ pain, such as the anterior insula, the anterior midcingulate cortex, and the primary somatosensory cortex. In addition, we found increased prosocial behavior under stress. Furthermore, activation in the anterior midcingulate cortex mediated the effects of stress on prosocial behavior. However, stressed participants also displayed stronger and inappropriate other-related responses in situations which required them to take the perspective of another person, and to regulate their automatic affective responses. Thus, while acute stress may increase prosocial behavior by intensifying the sharing of others’ emotions, this comes at the cost of reduced cognitive appraisal abilities. Depending on the contextual constraints, stress may therefore affect empathy in ways that are either beneficial or detrimental. PMID:27798249
Wright, Jonathan; McDonald, Paul G.; te Marvelde, Luc; Kazem, Anahita J. N.; Bishop, Charles M.
2010-01-01
Indirect fitness benefits from kin selection can explain why non-breeding individuals help raise the young of relatives. However, the evolution of helping by non-relatives requires direct fitness benefits, for example via group augmentation. Here, we examine nest visit rates, load sizes and prey types delivered by breeding pairs and their helpers in the cooperatively breeding bell miner (Manorina melanophrys). In this system, males remain in their natal colony while young females typically disperse, and helpers of both sexes often assist at multiple nests concurrently. We found extremely clear evidence for the expected effect of genetic relatedness on individual helping effort per nest within colonies. This positive incremental effect of kinship was facultative—i.e. largely the result of within-individual variation in helping effort. Surprisingly, no sex differences were detectable in any aspect of helping, and even non-relatives provided substantial aid. Helpers and breeders of both sexes regulated their provisioning effort by responding visit-by-visit to changes in nestling begging. Helping behaviour in bell miners therefore appears consistent with adaptive cooperative investment in the brood, and kin-selected care by relatives. Similar investment by ‘unrelated’ helpers of both sexes argues against direct fitness benefits, but is perhaps explained by kin selection at the colony level. PMID:19846458
The Faber–Jackson relation and Fundamental Plane from halo abundance matching
Desmond, Harry; Wechsler, Risa H.
2016-11-02
The Fundamental Plane (FP) describes the relation between the stellar mass, size, and velocity dispersion of elliptical galaxies; the Faber–Jackson relation (FJR) is its projection on to {mass, velocity} space. In this work, we re-deploy and expand the framework of Desmond & Wechsler to ask whether abundance matching-based Λ-cold dark matter models which have shown success in matching the spatial distribution of galaxies are also capable of explaining key properties of the FJR and FP, including their scatter. Within our framework, agreement with the normalization of the FJR requires haloes to expand in response to disc formation. We find thatmore » the tilt of the FP may be explained by a combination of the observed non-homology in galaxy structure and the variation in mass-to-light ratio produced by abundance matching with a universal initial mass function, provided that the anisotropy of stellar motions is taken into account. However, the predicted scatter around the FP is considerably increased by situating galaxies in cosmologically motivated haloes due to the variations in halo properties at fixed stellar mass and appears to exceed that of the data. Finally, this implies that additional correlations between galaxy and halo variables may be required to fully reconcile these models with elliptical galaxy scaling relations.« less
Evolutionary history and distance dependence control survival of dipterocarp seedlings.
Bagchi, Robert; Press, Malcolm C; Scholes, Julie D
2010-01-01
One important hypothesis to explain tree-species coexistence in tropical forests suggests that increased attack by natural enemies near conspecific trees gives locally rare species a competitive advantage. Host ranges of natural enemies generally encompass several closely related plant taxa suggesting that seedlings should also do poorly around adults of closely related species. We investigated the effects of adult Parashorea malaanonan on seedling survival in a Bornean rain forest. Survival of P. malaanonan seedlings was highest at intermediate distances from parent trees while heterospecific seedlings were unaffected by distance. Leaf herbivores did not drive this relationship. Survival of seedlings was lowest for P. malaanonan, and increased with phylogenetic dissimilarity from this species, suggesting that survival of close relatives of common species is reduced. This study suggests that distance dependence contributes to species coexistence and highlights the need for further investigation into the role of shared plant enemies in community dynamics.
Drought sensitivity predicts habitat size sensitivity in an aquatic ecosystem.
Amundrud, Sarah L; Srivastava, Diane S
2015-07-01
Species and trophic richness often increase with habitat size. Although many ecological processes have been evoked to explain both patterns, the environmental stress associated with small habitats has rarely been considered. We propose that larger habitats may be species rich simply because their environmental conditions are within the fundamental niche of more species; larger habitats may also have more trophic levels if traits of predators render them vulnerable to environmental stress. We test this hypothesis using the aquatic insect larvae in water-filled bromeliads. In bromeliads, the probability of desiccation is greatest in small plants. For the 10 most common bromeliad insect taxa, we ask whether differences in drought tolerance and regional abundances between taxa predict community and trophic composition over a gradient of bromeliad size. First, we used bromeliad survey data to calculate the mean habitat size of occurrence of each taxon. Comparing the observed mean habitat size of occurrence to that expected from random species assembly based on differences in their regional abundances allowed us to obtain habitat size sensitivity indices (as Z scores) for the various insect taxa. Second, we obtained drought sensitivity indices by subjecting individual insects to drought and measuring the effects on relative growth rates in a mesocosm experiment. We found that drought sensitivity strongly, predicts habitat size sensitivity in bromeliad insects. However, an increase in trophic richness with habitat size could not be explained by an increased sensitivity of predators to drought, but rather by sampling effects, as predators were rare compared to lower trophic levels. This finding suggests that physiological tolerance to environmental stress can be relevant in explaining the universal increase in species with habitat size.
Almeida, Joanna; Bécares, Laia; Erbetta, Kristin; Bettegowda, Vani R; Ahluwalia, Indu B
2018-02-13
Introduction Racial/ethnic inequities in low birth weight (LBW) and preterm birth (PTB) persist in the United States. Research has identified numerous risk factors for adverse birth outcomes; however, they do not fully explain the occurrence of, or inequalities in PTB/LBW. Stress has been proposed as one explanation for differences in LBW and PTB by race/ethnicity. Methods Using the Pregnancy Risk Assessment Monitoring System (PRAMS) data from 2012 to 2013 for 21 states and one city (n = 15,915) we used Poisson regression to estimate the association between acute, financial and relationship stressors and LBW and PTB, and to examine the contribution of these stressors individually and simultaneously to racial/ethnic differences in LBW and PTB. Results Adjusting for age and race/ethnicity, acute (p < 0.001), financial (p < 0.001) and relationship (p < 0.05) stressors were associated with increased risk of LBW, but only acute (p < 0.05) and financial (p < 0.01) stress increased risk of PTB. Across all models, non-Hispanic blacks had higher risk of LBW and PTB relative to non-Hispanic whites (IRR 1.87, 95% CI 1.55, 2.27 and IRR 1.46, 95% CI 1.18, 1.79). Accounting for the effects of stressors attenuated the risk of LBW and PTB by 17 and 22% respectively, but did not fully explain the increased likelihood of LBW and PTB among non-Hispanic blacks. Discussion Results of this study demonstrate that stress may increase the risk of LBW and PTB. While stressors may contribute to racial/ethnic differences in LBW and PTB, they do not fully explain them. Mitigating stress during pregnancy may help promote healthier birth outcomes and reduce racial/ethnic inequities in LBW and PTB.
[Physical activity and reproductive health].
Sundgot-Borgen, J
2000-11-20
The purpose of this article is to review the present knowledge about physical activity and reproductive health. Medline and manual search for articles related to exercise and menstrual function, and exercise and pregnancy were performed. Repetitive intensive exercise with increased stress hormone utilisation seems to partly explain the disturbances in the hypothalamic-pituitary-adrenal axis. The prevalence of menstrual irregularities is higher among athletes who participate in sports in which leanness is considered important for performance. Most of the studies concerning exercise-induced amenorrhoea have focused on low body weight and low fat ratio of body weight. However, energy drain and nutrient deficiency have been found to be important variables explaining menstrual irregularity in athletes. Loss of bone mass is related to menstrual irregularities hence it is important that menstrual irregularity not is considered a "normal" aspect of being an athlete. There are a number of positive effects and a few hypothetical risks related to exercise during pregnancy. There are no clinically controlled studies allowing us to draw conclusions about the effect of intensive training during pregnancy. Physically active women should be aware of the importance of sufficient energy intake to keep their regular menstrual cycle. Moderate exercise during pregnancy is recommended.
Fox, Bryanna Hahn; Farrington, David P
2016-12-01
Developmental and life-course (DLC) theories of crime aim to identify the causes and correlates of offending over the life span, focusing on the within-individual variations that result in criminal and delinquent behavior. Although there are several notable theories in the field, few contain both developmental and situational factors related to offending, and none explain why individuals commit crimes in different ways. This study aims to address these issues by developing typologies of burglars based on developmental and situational characteristics to help identify the various criminal career paths of the offenders, and how these different criminal careers may relate to the commission of offenses. Results of this study indicate that there are five different criminal career paths among the sampled burglars and four different styles of committing the same offense, and that burglars with certain criminal career features tend to commit a specific style of burglary. Through this research, we aim to extend DLC theories to create a more practical and contextual explanation of the relationship between criminal careers and the commission of offenses, and increase the level of within-individual explained variance in criminal behavior.
The Role of the CMB in Redshift Related Departures from the Gao–Solomon Relation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tunnard, R.; Greve, T. R., E-mail: richard.tunnard.13@ucl.ac.uk
A strong correlation between the far-IR and HCN(1−0) line luminosities, known as the Gao–Solomon relation, has been observed to hold over more than 10 orders of magnitude in the local universe. Departures from this relation at redshifts ≳1.5 have been interpreted as evidence for increased dense gas star formation efficiency in luminous galaxies during the period of peak of star formation in the history of the universe. We examine whether the offsets from the relation can be explained by the hotter Cosmic Microwave Background (CMB) at high redshift, which, due to a loss of contrast against the hotter background, reducesmore » the observable molecular-line flux far more significantly than the far-IR continuum bands. Simple line-of-sight modeling argues for highly significant departures from the Gao–Solomon relation at high redshift for kinetic temperatures ∼15 K, while more complex toy-galaxy models based on NGC 1068 suggest a much weaker effect with the galaxy integrated HCN line flux falling by only 10% at z = 3, within the intrinsic scatter of the relation. We conclude that, while the CMB is unlikely to explain the deviations reported in the literature, it may introduce a second-order effect on the relation by raising the low-luminosity end of the Gao–Solomon relation in cooler galaxies. A similar examination of the CO-IR relation finds tantalizing signs of the CMB having a measurable effect on the integrated CO emission in high-redshift galaxies, but these signs cannot be confirmed with the current data.« less
The Role of the CMB in Redshift Related Departures from the Gao-Solomon Relation
NASA Astrophysics Data System (ADS)
Tunnard, R.; Greve, T. R.
2017-11-01
A strong correlation between the far-IR and HCN(1-0) line luminosities, known as the Gao-Solomon relation, has been observed to hold over more than 10 orders of magnitude in the local universe. Departures from this relation at redshifts ≳1.5 have been interpreted as evidence for increased dense gas star formation efficiency in luminous galaxies during the period of peak of star formation in the history of the universe. We examine whether the offsets from the relation can be explained by the hotter Cosmic Microwave Background (CMB) at high redshift, which, due to a loss of contrast against the hotter background, reduces the observable molecular-line flux far more significantly than the far-IR continuum bands. Simple line-of-sight modeling argues for highly significant departures from the Gao-Solomon relation at high redshift for kinetic temperatures ˜15 K, while more complex toy-galaxy models based on NGC 1068 suggest a much weaker effect with the galaxy integrated HCN line flux falling by only 10% at z = 3, within the intrinsic scatter of the relation. We conclude that, while the CMB is unlikely to explain the deviations reported in the literature, it may introduce a second-order effect on the relation by raising the low-luminosity end of the Gao-Solomon relation in cooler galaxies. A similar examination of the CO-IR relation finds tantalizing signs of the CMB having a measurable effect on the integrated CO emission in high-redshift galaxies, but these signs cannot be confirmed with the current data.
Computer ethics and teritary level education in Hong Kong
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, E.Y.W.; Davison, R.M.; Wade, P.W.
1994-12-31
This paper seeks to highlight some ethical issues relating to the increasing proliferation of Information Technology into our everyday lives. The authors explain their understanding of computer ethics, and give some reasons why the study of computer ethics is becoming increasingly pertinent. The paper looks at some of the problems that arise in attempting to develop appropriate ethical concepts in a constantly changing environment, and explores some of the ethical dilemmas arising from the increasing use of computers. Some initial research undertaken to explore the ideas and understanding of tertiary level students in Hong Kong on a number of ethicalmore » issues of interest is described, and our findings discussed. We hope that presenting this paper and eliciting subsequent discussion will enable us to draw up more comprehensive guidelines for the teaching of computer related ethics to tertiary level students, as well as reveal some directions for future research.« less
Gonzales, Nancy A; Germán, Miguelina; Kim, Su Yeong; George, Preethy; Fabrett, Fairlee C; Millsap, Roger; Dumka, Larry E
2008-03-01
This study of 598 7th grade students of Mexican origin examined the role of traditional cultural values as a mediator of the effects of immigrant status, Mexican cultural orientation and Anglo cultural orientation on adolescent externalizing behavior and academic engagement. Immigrant status of adolescents and their maternal caregivers uniquely predicted increased Mexican cultural orientation and decreased Anglo cultural orientation, and both Mexican and Anglo cultural orientation related positively to adolescents' endorsement of traditional cultural values. Endorsement of traditional cultural values related, in turn, to decreased externalizing behaviors and increased academic engagement and these findings were replicated across adolescent and teacher report of these two outcomes. Tests of mediation provided further evidence to support these pathways. Findings support the central importance of traditional cultural values as a protective resource that explains why immigrant youth exhibit fewer externalizing problems and increased academic engagement when compared to their second and third generation peers.
NASA Astrophysics Data System (ADS)
Aerts, Wouter; Joosen, Pieter; Widjaja, Devy; Varon, Carolina; Vandeput, Steven; Van Huffel, Sabine; Aubert, Andre E.
2013-02-01
Gravity changes during partial-G parabolic flights (0g -0.16g - 0.38g) lead to changes in modulation of the autonomic nervous system (ANS), studied via the heart rate variability (HRV) and blood pressure variability (BPV). HRV and BPV were assessed via classical time and frequency domain measures. Mean systolic and diastolic blood pressure show both increasing trends towards higher gravity levels. The parasympathetic and sympathetic modulation show both an increasing trend with decreasing gravity, although the modulation is sympathetic predominant during reduced gravity. For the mean heart rate, a non-monotonic relation was found, which can be explained by the increased influence of stress on the heart rate. This study shows that there is a relation between changes in gravity and modulations in the ANS. With this in mind, countermeasures can be developed to reduce postflight orthostatic intolerance.
Predisposing factors for atrial fibrillation in the elderly
Wasmer, Kristina; Eckardt, Lars; Breithardt, Günter
2017-01-01
Atrial fibrillation (AF) in the elderly occurs as a consequence of cardiovascular aging and an age related increase of comorbidity. Several predisposing factors for AF have been identified for the overall AF population. Most of them, cardiovascular disease in particular, play a role in younger and older patients. The longer time period during which these risk factors can cause structural changes that ultimately lead to AF may, at least in part, explain the association between age and AF. In addition, less well defined age-related changes in cellular electrophysiologic properties and structure predispose to AF in the elderly. PMID:28592961
Falling Enrolments and Rising Expenditures: The School Board's Dilemma.
ERIC Educational Resources Information Center
Sharples, Brian
Previous increases in the costs of Canadian education were easily explained by rising enrollments. In an era of declining enrollments, increased costs are much more difficult to explain. One reason for increased costs is the large proportion of Canadian student population concentrated in high schools where programs are more expensive than at other…
Tapping Transaction Costs to Forecast Acquisition Cost Breaches
2016-01-01
Diameter Bomb Increment II (SDB II) Space Based Infrared System (SBIRS) High Program Standard Missile (SM) - 2 Block IV Stryker Family of Vehicles...some limitations. First, the activities included in this category will vary somewhat from contractor to contractor. As a result, a small portion of...contract may vary over time as new costs are defined by the contractor as being related to SE/PM. This could explain a small portion of the increase in
Nothing From Everything- A Unified Theory
NASA Astrophysics Data System (ADS)
Mehra, Vijay Kumar
2016-07-01
Nothing From Everything-A Unified Theory is a philosophical insight into principles of nature through principle of complementary spontaneity and principle of vertical continuity. This work is intended to explain various cosmological phenomena in light of behaviour of particles in range of their respective and relative speed of light. This theory explains creation of Universe from nothing or zero spacetime through scalar energy field collapsing into Higgs field resulting into giving mass to various particles. The energy particles taking origin from nothing while moving away from zero space-time would create space-time of their own order because energy/matter needs space to exist. The particles while moving away from zero space-time would end up in breaking symmetry of matter/energy at their mass infinity (highest possible mass of any particle, which is function of speed of spin). This break in symmetry would lead to curving of particles upon themselves and hence would lead to creation of antiparticles going back in time towards zero spacetime. Therefore the Universe could have been created by alternate layers of particles and antiparticles and also alternate layers of matter and antimatter with decelerating speed of light, which would lead to creation a closed and flat Universe. With increase in mass of Universe (creation of more and more Universe's matter from nothing), the gravitational force of Universe is bound to increase and hence with quantum by quantum increase in gravity, it would apply brakes on relative speed of photon/light out of its reference frame or designated space and hence speed of photon would decrease. If closed and flat Universe was created with decelerating speed of light, then such Universe is bound to contract back with accelerating speed of light which would have inverse impact on gravitational constant across various spacetime zones of Universe. And hence mass bodies would drift away spontaneously purely on basis and proportional to distance square between mass bodies with accelerating speed of light, but in actual such Universe would be contracting rather than expanding. Furthermore, this theory explains how particles (when moving away from zero space-time) acquire spin, whose force vector acts centrifugally and neutralizes the quantum gravitational force of particle which acts centripetally. While in case of antiparticles both spin force and gravitational force acts towards centre of particles and they are bound to create singularity of zero spacetime. This theory further explains motion of photon/anti-photon in light of space displacement. The time is nothing but is a measure of rate of space displacement. Where there is no space displacement, there is no time. Any force, like gravity, which acts against space displacement must act against time and hence such forces would lead to slowing of time. This theory further explains about curvature of space-time, relative existence of time orders across Universe, black holes including atomic black holes, other Universes, virtual Universe, time travel, existence of life on other planets, numbers of Universe which govern dynamics of Universe, quantum of Universe i.e. existence of particle-antiparticle in space-time and relation of particles with Higgs field, origin of spin and charge of particles, reason for uncertainty principle and Pauli's exclusion principle, space-time dimensions, and other relevant topics of Astrophysics and quantum Physics.
Modelling of cardiac-related changes in lung resistivity measured with EITS.
Zhao, T X; Brown, B H; Nopp, P; Wang, W; Leathard, A D; Lu, L Q
1996-11-01
Resistivity data from 9.6 kHZ to 1.2 MHz were recorded from eight normal subjects using an electrical impedance tomographic spectroscopy (EITS) system and then averaged to a mean cardiac cycle using the ECG gating technique. The Cole-Cole model, that is, extracellular resistance R connected in parallel with intracellular resistance S and membrane capacitance C in series, with a distribution parameter a, was applied to model the frequency characteristics and to produce parametric images. During systole, SC and RC were found to decrease and FR increase. The changes in R/S were not consistent among the subjects. We estimated the peak changes in R, S and C to be -2.5%, -3.3% and -7.6% respectively. The results can be explained by considering the blood vessels as spheres of different sizes with blood inside them. The decrease in R during systole might be caused by the increased blood content in relatively large vessels, whereas that in S by the increased blood volume in relatively small vessels. The capacitance of blood is normally smaller than that of lung tissue, whereas FR blood is higher than that of lung tissue. Hence, as blood content increases, C should decrease and FR increase.
Coons, Stephen Joel; Wendel, Christopher; Hornbrook, Mark C; Herrinton, Lisa; Grant, Marcia; Krouse, Robert S
2009-01-01
Purpose The purpose of this analysis was to determine the unique contribution of household income to the variance explained in psychological well-being (PWB) among a sample of colorectal cancer (CRC) survivors. Methods This study is a secondary analysis of data collected as part of the Health-Related Quality of Life in Long-Term Colorectal Cancer Survivors Study, which included CRC survivors with (cases) and without (controls) ostomies. The dataset included socio-demographic, health status, and health-related quality of life (HRQOL) information. HRQOL was assessed with the modified City of Hope Quality of Life (mCOH-QOL)-Ostomy questionnaire and SF-36v2. To assess the relationship between income and PWB, a hierarchical linear regression model was constructed combining data from both cases and controls. Results After accounting for the proportion of variance in PWB explained by the other independent variables in the model, the additional variance explained by income was significant (R2 increased from 0.228 to 0.250; p = 0.006). Conclusions Although the study design does not allow causal inference, these results demonstrate a significant relationship between income and PWB in CRC survivors. The findings suggest that for non-randomized group comparisons of HRQOL, income should, at the very least, be included as a control variable in the analysis. PMID:19132550
Buck, Nicole M L; Leenaars, Ellie P E M; Emmelkamp, Paul M G; van Marle, Hjalmar J C
2012-11-01
Studies have found that male batterers are more often insecurely attached as compared with nonbatterers. However, it is still not clear how insecure attachment is related to domestic violence. Many studies compared batterers and nonbatterers regarding pathological personality characteristics that are related to attachment (e.g., dependency, jealousy) and generally found that batterers report more personality characteristics. However, these studies did not investigate which role these characteristics played in the relationship between insecure attachment and battering. The first aim of this study is to test which personality characteristics are good candidates to explain the relationship between insecure attachment and domestic violence. The second aim is to test whether personality characteristics are predictive of battering over and above attachment. Seventy-two mainly court-mandated family-only males who were in group treatment for battering are allocated to a securely and an insecurely attached group and compared with 62 nonbatterers. Using questionnaires, self-esteem, dependency, general distrust, distrust in partner, jealousy, lack of empathy, separation anxiety, desire for control, and impulsivity were assessed. This was the first study that examined distrust, separation anxiety, and desire for control in relation to battering. The results show that the relationship between insecure attachment and domestic violence can be explained by separation anxiety and partner distrust. Moreover, only partner distrust increased the risk for battering over and above insecure attachment. The findings suggest the presence of two subtypes among batterers based on attachment style, which has similarities to the family-only and dysphoric-borderline subtypes suggested by Holtzworth-Munroe and Stuart. Implications of the present findings for therapy are discussed.
Tousignant, Michel; Corriveau, Hélène; Roy, Pierre-Michel; Desrosiers, Johanne; Dubuc, Nicole; Hébert, Réjean; Tremblay-Boudreault, Valérie; Beaudoin, Audrée-Jeanne
2012-01-01
To assess some fall-related clinical variables (balance, gait, fear of falling, functional autonomy, self-actualization and self-efficacy) that might explain the fact that supervised Tai Chi has a better impact on preventing falls compared to a conventional physiotherapy program. The participants (152 older adults over 65 who were admitted to a geriatric day hospital program) were randomly assigned to either a supervised Tai Chi group or the usual physiotherapy. The presence of the clinical variables related to falls was evaluated before the intervention (T1), immediately after (T2), and 12 months after the end of the intervention (T3). Both exercise programs significantly improved fall-related outcomes but only the Tai Chi intervention group decreased the incidence of falls. For both groups, most variables followed the same pattern, i.e. showed significant improvement with the intervention between T1 and T2, and followed by a statistically significant decrease at the T3 evaluation. However, self-efficacy was the only variable that improved solely with the Tai Chi intervention (p = 0.001). The impact of supervised Tai Chi on fall prevention can not be explained by a differential effect on balance, gait and fear of falling. It appeared to be related to an increase of general self-efficacy, a phenomenon which is not seen in the conventional physiotherapy program.
Cheng, Yi-Ru; Martin, Thomas E.
2012-01-01
Different body components are thought to trade off in their growth and development rates, but the causes for relative prioritization of any trait remains a critical question. Offspring of species at higher risk of predation might prioritize development of locomotor traits that facilitate escaping risky environments over growth of mass. We tested this possibility in 12 altricial passerine species that differed in their risk of nest predation. We found that rates of growth and development of mass, wings, and endothermy increased with nest predation risk across species. In particular, species with higher nest predation risk exhibited relatively faster growth of wings than of mass, fledged with relatively larger wing sizes and smaller mass, and developed endothermy earlier at relatively smaller mass. This differential development can facilitate both escape from predators and survival outside of the nest environment. Tarsus growth was not differentially prioritized with respect to nest predation risk, and instead all species achieved adult tarsus size by age of fledging. We also tested whether different foraging modes (aerial, arboreal, and ground foragers) might explain the variation of differential growth of locomotor modules, but we found that little residual variation was explained. Our results suggest that differences in nest predation risk among species are associated with relative prioritization of body components to facilitate escape from the risky nest environment.
Vieira, Verónica M.; Fabian, M. Patricia; Webster, Thomas F.; Levy, Jonathan I.; Korrick, Susan A.
2017-01-01
Abstract Attention-deficit/hyperactivity disorder (ADHD) has an uncertain etiology, with potential contributions from different risk factors such as prenatal environmental exposure to organochlorines and metals, social risk factors, and genetics. The degree to which geographic variability in ADHD is independent of, or explained by, risk factors may provide etiological insight. We investigated determinants of geographic variation in ADHD-related behaviors among children living near the polychlorinated biphenyl–contaminated New Bedford Harbor (NBH) Superfund site in Massachusetts. Participants were 573 children recruited at birth (1993–1998) who were born to mothers residing near the NBH site. We assessed ADHD-related behaviors at age 8 years using Conners’ Teacher Rating Scale–Revised: Long Version. Adjusted generalized additive models were used to smooth the association of pregnancy residence with ADHD-related behaviors and assess whether prenatal organochlorine or metal exposures, sociodemographic factors, or other factors explained spatial patterns. Models that adjusted for child's age and sex displayed significantly increased ADHD-related behavior among children whose mothers resided west of the NBH site during pregnancy. These spatial patterns persisted after adjusting for prenatal exposure to organochlorines and metals but were no longer significant after controlling for sociodemographic factors. The findings underscore the value of spatial analysis in identifying high-risk subpopulations and evaluating candidate risk factors. PMID:28444119
Decreases in beetle body size linked to climate change and warming temperatures.
Tseng, Michelle; Kaur, Katrina M; Soleimani Pari, Sina; Sarai, Karnjit; Chan, Denessa; Yao, Christine H; Porto, Paula; Toor, Anmol; Toor, Harpawantaj S; Fograscher, Katrina
2018-05-01
Body size is a fundamental ecological trait and is correlated with population dynamics, community structure and function, and ecosystem fluxes. Laboratory data from broad taxonomic groups suggest that a widespread response to a warming world may be an overall decrease in organism body size. However, given the myriad of biotic and abiotic factors that can also influence organism body size in the wild, it is unclear whether results from these laboratory assays hold in nature. Here we use datasets spanning 30 to 100 years to examine whether the body size of wild-caught beetles has changed over time, whether body size changes are correlated with increased temperatures, and we frame these results using predictions derived from a quantitative review of laboratory responses of 22 beetle species to temperature. We found that 95% of laboratory-reared beetles decreased in size with increased rearing temperature, with larger-bodied species shrinking disproportionately more than smaller-bodied beetles. In addition, the museum datasets revealed that larger-bodied beetle species have decreased in size over time, that mean beetle body size explains much of the interspecific variation in beetle responses to temperature, and that long-term beetle size changes are explained by increases in autumn temperature and decreases in spring temperature in this region. Our data demonstrate that the relationship between body size and temperature of wild-caught beetles matches relatively well with results from laboratory studies, and that variation in this relationship is largely explained by interspecific variation in mean beetle body size. This long-term beetle dataset is one of the most comprehensive arthropod body size datasets compiled to date, it improves predictions regarding the shrinking of organisms with global climate change, and together with the meta-analysis data, call for new hypotheses to explain why larger-bodied organisms may be more sensitive to temperature. © 2018 The Authors. Journal of Animal Ecology © 2018 British Ecological Society.
Age-related regulation of genes: slow homeostatic changes and age-dimension technology
NASA Astrophysics Data System (ADS)
Kurachi, Kotoku; Zhang, Kezhong; Huo, Jeffrey; Ameri, Afshin; Kuwahara, Mitsuhiro; Fontaine, Jean-Marc; Yamamoto, Kei; Kurachi, Sumiko
2002-11-01
Through systematic studies of pro- and anti-blood coagulation factors, we have determined molecular mechanisms involving two genetic elements, age-related stability element (ASE), GAGGAAG and age-related increase element (AIE), a unique stretch of dinucleotide repeats (AIE). ASE and AIE are essential for age-related patterns of stable and increased gene expression patterns, respectively. Such age-related gene regulatory mechanisms are also critical for explaining homeostasis in various physiological reactions as well as slow homeostatic changes in them. The age-related increase expression of the human factor IX (hFIX) gene requires the presence of both ASE and AIE, which apparently function additively. The anti-coagulant factor protein C (hPC) gene uses an ASE (CAGGAG) to produce age-related stable expression. Both ASE sequences (G/CAGAAG) share consensus sequence of the transcriptional factor PEA-3 element. No other similar sequences, including another PEA-3 consensus sequence, GAGGATG, function in conferring age-related gene regulation. The age-regulatory mechanisms involving ASE and AIE apparently function universally with different genes and across different animal species. These findings have led us to develop a new field of research and applications, which we named “age-dimension technology (ADT)”. ADT has exciting potential for modifying age-related expression of genes as well as associated physiological processes, and developing novel, more effective prophylaxis or treatments for age-related diseases.
Zhang, Qiong; Shi, Jiannong; Luo, Yuejia; Zhao, Daheng; Yang, Jie
2006-05-15
To investigate the differences in event-related potential parameters related to children's intelligence, we selected 15 individuals from an experimental class of intellectually gifted children and 13 intellectually average children as control to finish three types of visual search tasks (Chinese words, English letters and Arabic numbers). We recorded the electroencephalogram and calculated the peak latencies and amplitudes. Our results suggest comparatively increased P3 amplitudes and shorter P3 latencies in brighter individuals than in less intelligent individuals, but this expected neural efficiency effect interacted with task content. The differences were explained by a more spatially and temporally coordinated neural network for more intelligent children.
Neighborhoods and HIV: A Social Ecological Approach to Prevention and Care
Latkin, Carl A.; German, Danielle; Vlahov, David
2013-01-01
Neighborhood factors have been linked to HIV risk behaviors, HIV counseling and testing, and HIV medical care. However, the social–psychological mechanisms that connect neighborhood factors to HIV-related behaviors have not been fully determined. In this paper we review the research on neighborhood factors and HIV-related behaviors, approaches to measuring neighborhoods, and mechanism that may help to explain how the physical and social environment within neighborhoods may lead to HIV related behaviors. We then discuss organizational, geographic, and social network approaches to intervene in neighborhoods to reduce HIV transmission and facilitate HIV medical care with the goal of reducing morbidity and mortality and increasing social and psychological well-being. PMID:23688089
A simple but powerful theory of the moon illusion.
Baird, J C; Wagner, M; Fuld, K
1990-08-01
Modification of Restle's theory (1970) explains the moon illusion and related phenomena on the basis of three principles: (1) The apparent sizes of objects are their perceived visual angles. (2) The apparent size of the moon is determined by the ratio of the angular extent of the moon relative to the extents subtended by objects composing the surrounding context, such as the sky and things on the ground. (3) The visual extents subtended by common objects of a constant physical size decrease systematically with increasing distance from the observer. Further development of this theory requires specification of both the components of the surrounding context and their relative importance in determining the apparent size and distance of the moon.
Miller, Jordan A G; Rege, Robert V; Ko, Clifford Y; Livingston, Edward H
2004-07-01
Esophageal cancer mortality is increased in African Americans relative to white patients. The reasons for this are unknown but are thought to be related to inadequate access to health care secondary to a higher poverty rate in African American populations. The National Health Interview Survey database for years 1986 to 1994 were combined and linked to the National Death Index. Individuals who died from esophageal carcinoma were assessed in the combined database, thus enabling detailed analysis of their socioeconomic status, race, and health care access. Poverty was 4-fold more frequent in African Americans who died from esophageal carcinoma than whites. Despite poverty, African American patients' access to health care was good and was not statistically related to increased mortality. Although the esophageal carcinoma mortality rate is higher in African Americans than in whites, it is not clearly related to the presence of poverty or to limited health care access. The higher mortality may be related to lifestyle differences, environmental exposure, or difference in disease biology, but it is not related exclusively to socioeconomic factors.
Measurement of time processing ability and daily time management in children with disabilities.
Janeslätt, Gunnel; Granlund, Mats; Kottorp, Anders
2009-01-01
Improvement is needed in methods for planning and evaluating interventions designed to facilitate daily time management for children with intellectual disability, Asperger syndrome, or other developmental disorders. The aim of this study was to empirically investigate the hypothesized relation between children's time processing ability (TPA), daily time management, and self-rated autonomy. Such a relationship between daily time management and TPA may support the idea that TPA is important for daily time management and that children with difficulties in TPA might benefit from intervention aimed at improving daily time management. Participants were children aged 6 to 11 years with dysfunctions such as attention-deficit/hyperactivity disorder, autism, or physical or intellectual disabilities (N = 118). TPA was measured with the instrument KaTid. All data were transformed to interval measures using applications of Rasch models and then further analysed with correlation and regression analysis. The results demonstrate a moderate significant relation between the parents' ratings of daily time management and TPA of the children, and between the self-rating of autonomy and TPA. There was also a significant relation between self-ratings of autonomy and the parents' rating of the children's daily time management. Parents' ratings of their children's daily time management explain 25% of the variation in TPA, age of the children explains 22%, while the child's self-rating of autonomy can explain 9% of the variation in TPA. The three variables together explain 38% of the variation in TPA. The results indicate the viability of the instrument for assessing TPA also in children with disabilities and that the ability measured by KaTid is relevant for daily time management. TPA seems to be a factor for children's daily time management that needs to be taken into consideration when planning and evaluating interventions designed to facilitate everyday functioning for children with cognitive impairments. The findings add to the increasing knowledge base about children with time processing difficulties and contribute to better methods aimed at improving these children's daily time management. Further research is needed to examine if there are differences in TPA related to specific diagnosis or other child characteristics.
Sociodemographic characteristics of mother’s population and risk of preterm birth in Chile
2013-01-01
Background Preterm birth is a global problem in Perinatal and infant Health. Currently is gaining a growing attention. Rates of preterm birth have increased in most countries, producing a dramatic impact on public health. Factors of diverse nature have been associated to these trends. In Chile, preterm birth has increased since 90. Simultaneously, the advanced demographic transition has modified the characteristics of woman population related to maternity. The principal objective of this study is to analyze some sociodemographic characteristics of the maternal population over time, and their possible association to rates of preterm birth. The second aim is to identify groups of mothers at high risk of having a preterm child. Methods This population-based study examined all liveborn singletons in Chile from 1991 to 2008; divided in three periods. Preterm birth rates were measured as % births <37 weeks of gestation. Logistic regression assessed the risk of preterm birth associated with mother’s age, parity, and marital status, expressed as crude and adjusted odds ratios. Results Over time, rates of preterm birth increased in overall population, especially during the third period (2001–2008). In the same time, characteristics of maternal population changed: significant increase of extreme reproductive ages, significant decrease in parity and increase in mothers living without a partner. Risk of preterm birth remained higher in groups of mothers: <18 and >38 years of age; without a partner; primiparas and grandmultiparas. However, global increase in preterm birth was not explained by the modification of socio demographics characteristics of maternal population. Conclusions Some socio demographic characteristics remained associated with preterm birth over time. These associations allowed identifying five groups of mothers at higher risk to have a preterm child in the population. Increase in overall preterm birth affected all women, even those considered at “low sociodemographic risk” and the contribution of more recent period (2001–2008) to this increase is greater. Then, studied factors couldn’t explain the increase in preterm birth. Further research will have to consider other factors affecting maternal population that could explain the observed trend of preterm birth. PMID:23680406
NASA Astrophysics Data System (ADS)
Hájek, Michal; Dudová, Lydie; Hájková, Petra; Roleček, Jan; Moutelíková, Jitka; Jamrichová, Eva; Horsák, Michal
2016-02-01
The south-western part of the White Carpathians (Czech Republic, Slovakia) is known for its exceptional grassland diversity and occurrence of many species with disjunct distribution patterns, including isolated populations of continental forest-steppe species. The north-eastern part of the mountain range lacks many of these species and has clearly lower maxima of grassland species richness. While climatic and edaphic conditions of both regions largely overlap, their specific environmental history has been hypothesized to explain the exceptional richness in the south-western part. We explored an entire-Holocene record (9650 BC onwards), the first one from the north-eastern part, to find out whether differences in history may explain regional patterns of species rarity and richness. We analysed pollen, macrofossils and molluscs and dated the sequence with 13 radiocarbon dates. We further reconstructed past human activities using available archaeological evidence. Based on this analysis, the Early-Holocene landscape was reconstructed as semi-open with broad-leaved trees (elm and lime) appearing already around 9500 BC. Lime reached a relative abundance of as much as 60% around 8700 BC. All analysed proxies support the existence of dense lime-dominated woodland during the forest optimum starting after climate moistening around 6800 BC, some 2200 years before the first signs of slight forest opening in the Late Neolithic. During the Bronze and Iron Ages, human pressure increased, which led to a decrease in lime and an increase in oak, hornbeam, grasses and grassland snails; nevertheless, forests still dominated the landscape and beech spread when human impact temporarily decreased. Colonisation after AD 1350 created the modern grassland-rich landscape. All available evidence confirmed an early post-Glacial expansion of broad-leaved trees, supporting the hypothesis on their glacial refugia in the Carpathians, as well as presence of closed-canopy forest well before the Neolithic. This environmental history was unfavourable for the survival of Early-Holocene forest-steppe species in the north-eastern White Carpathians and may explain the impoverished grassland flora compared to the south-western part. We conclude that contrasting Holocene histories may explain those patterns in species richness and distributions, which cannot be explained by recent environmental conditions alone.
Celeste, Roger Keller; Nadanovsky, Paulo
2010-10-01
To evaluate the association between income inequality, a public policy scale and to oral health. Analysis, using the Brazilian oral health survey in 2002-2003, included 23,573 15-19-year-old subjects clustered in 330 municipalities. Missing and decayed teeth and malocclusion assessments were the outcomes. Gini coefficient and a novel Scale of Municipal Public Policies were the main exposure variables. Individual level covariates were used as controls in multilevel regressions. An increase from the lowest to the highest Gini value in Brazil was associated with an increase in the number of missing (rate ratio, RR=2.11 confidence interval 95% 1.18-3.77) and decayed teeth (RR=2.92 CI 95% 1.83-4.65). After adjustment for public policies and water fluoridation, the Gini effect was non-significant and public policies explained most of the variation in missing and decayed teeth. The public policy scale remained significant after adjustment with a rate ratio of 0.64 for missing and 0.72 for decayed teeth. Neither Gini nor public policies were significantly related to malocclusion. The public policy effect on missing and decayed teeth was stronger among those with higher education and income. Income inequality effect was explained mainly by public policies, which had an independent effect that was greater among the better-off. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.
What makes migrant live-in home care workers in elder care be satisfied with their job?
Iecovich, Esther
2011-10-01
The study aims to examine job satisfaction of migrant live-in home care workers who provide care to frail older adults and to examine the extent to which quality of relationships between the care provider and care recipient and workplace characteristics is associated with job satisfaction. A convenience sample that included 335 dyads of Philippine workers and their frail care recipients were recruited through 2 national home care agencies and snowballing. Multiple regression analyses examined the extent to which workplace characteristics, quality of relationships, care recipient characteristics, and care worker characteristics explain job satisfaction. Scores for job satisfaction, quality of relationships, and workplace characteristics were strongly positive. Overall and intrinsic job satisfactions were explained by workers' qualifications, workplace characteristics, and quality of relationships from the perspective of care recipients, whereas satisfaction with benefits was affected by workplace characteristics and quality of relationships from the perspective of the care workers. Findings suggest that workers who were better qualified in terms of more years of formal education and more years as care workers and who reported improved workplace characteristics, in particular more job decision authority and variety, reported increased job satisfaction. Therefore, enabling migrant live-in care workers more job decision authority and variety may increase their job satisfaction. More research is needed to deepen our understanding of additional job-related characteristics that explain job satisfaction among this group of care workers.
Curvature Forces in Membrane Lipid-Protein Interactions
Brown, Michael F.
2012-01-01
Membrane biochemists are becoming increasingly aware of the role of lipid-protein interactions in diverse cellular functions. This review describes how conformational changes of membrane proteins—involving folding, stability, and membrane shape transitions—potentially involve elastic remodeling of the lipid bilayer. Evidence suggests that membrane lipids affect proteins through interactions of a relatively long-range nature, extending beyond a single annulus of next-neighbor boundary lipids. It is assumed the distance scale of the forces is large compared to the molecular range of action. Application of the theory of elasticity to flexible soft surfaces derives from classical physics, and explains the polymorphism of both detergents and membrane phospholipids. A flexible surface model (FSM) describes the balance of curvature and hydrophobic forces in lipid-protein interactions. Chemically nonspecific properties of the lipid bilayer modulate the conformational energetics of membrane proteins. The new biomembrane model challenges the standard model (the fluid mosaic model) found in biochemistry texts. The idea of a curvature force field based on data first introduced for rhodopsin gives a bridge between theory and experiment. Influences of bilayer thickness, nonlamellar-forming lipids, detergents, and osmotic stress are all explained by the FSM. An increased awareness of curvature forces suggests that research will accelerate as structural biology becomes more closely entwined with the physical chemistry of lipids in explaining membrane structure and function. PMID:23163284
Hung, George K; Ciuffreda, Kenneth J
2007-07-01
Previous theories of myopia development involved subtle and complex processes such as the sensing and analyzing of chromatic aberration, spherical aberration, spatial gradient of blur, or spatial frequency content of the retinal image, but they have not been able to explain satisfactorily the diverse experimental results reported in the literature. On the other hand, our newly proposed incremental retinal-defocus theory (IRDT) has been able to explain all of these results. This theory is based on a relatively simple and direct mechanism for the regulation of ocular growth. It states that a time-averaged decrease in retinal-image defocus area decreases the rate of release of retinal neuromodulators, which decreases the rate of retinal proteoglycan synthesis with an associated decrease in scleral structural integrity. This increases the rate of scleral growth, and in turn the eye's axial length, which leads to myopia. Our schematic analysis has provided a clear explanation for the eye's ability to grow in the appropriate direction under a wide range of experimental conditions. In addition, the theory has been able to explain how repeated cycles of nearwork-induced transient myopia leads to repeated periods of decreased retinal-image defocus, whose cumulative effect over an extended period of time results in an increase in axial growth that leads to permanent myopia. Thus, this unifying theory forms the basis for understanding the underlying retinal and scleral mechanisms of myopia development.
Pelegrín-Borondo, Jorge; Reinares-Lara, Eva; Olarte-Pascual, Cristina; Garcia-Sierra, Marta
2016-01-01
Today, technological implants are being developed to increase innate human capacities, such as memory or calculation speed, and to endow us with new ones, such as the remote control of machines. This study's aim was two-fold: first, to introduce a Cognitive-Affective-Normative (CAN) model of technology acceptance to explain the intention to use this technology in the field of consumer behavior; and second, to analyze the differences in the intention to use it based on whether the intended implant recipient is oneself or one's child (i.e., the moderating effect of the end user). A multi-group analysis was performed to compare the results between the two groups: implant "for me" (Group 1) and implant "for my child" (Group 2). The model largely explains the intention to use the insideable technology for the specified groups [variance explained (R (2)) of over 0.70 in both cases]. The most important variables were found to be "positive emotions" and (positive) "subjective norm." This underscores the need to broaden the range of factors considered to be decisive in technology acceptance to include variables related to consumers' emotions. Moreover, statistically significant differences were found between the "for me" and "for my child" models for "perceived ease of use (PEU)" and "subjective norm." These findings confirm the moderating effect of the end user on new insideable technology acceptance.
Manure-amended soil characteristics affecting the survival of E. coli O157:H7 in 36 Dutch soils.
Franz, Eelco; Semenov, Alexander V; Termorshuizen, Aad J; de Vos, O J; Bokhorst, Jan G; van Bruggen, Ariena H C
2008-02-01
The recent increase in foodborne disease associated with the consumption of fresh vegetables stresses the importance of the development of intervention strategies that minimize the risk of preharvest contamination. To identify risk factors for Escherichia coli O157:H7 persistence in soil, we studied the survival of a Shiga-toxin-deficient mutant in a set of 36 Dutch arable manure-amended soils (organic/conventional, sand/loam) and measured an array of biotic and abiotic manure-amended soil characteristics. The Weibull model, which is the cumulative form of the underlying distribution of individual inactivation kinetics, proved to be a suitable model for describing the decline of E. coli O157:H7. The survival curves generally showed a concave curvature, indicating changes in biological stress over time. The calculated time to reach the detection limit ttd ranged from 54 to 105 days, and the variability followed a logistic distribution. Due to large variation among soils of each management type, no differences were observed between organic and conventional soils. Although the initial decline was faster in sandy soils, no significant differences were observed in ttd between both sandy and loamy soils. With sandy, loamy and conventional soils, the variation in ttd was best explained by the level of dissolved organic carbon per unit biomass carbon DOC/biomC, with prolonged survival at increasing DOC/biomC. With organic soils, the variation in ttd was best explained by the level of dissolved organic nitrogen (positive relation) and the microbial species diversity as determined by denaturing gradient gel electrophoresis (negative relation). Survival increased with a field history of low-quality manure (artificial fertilizer and slurry) compared with high-quality manure application (farmyard manure and compost). We conclude that E. coli O157:H7 populations decline faster under more oligotrophic soil conditions, which can be achieved by the use of organic fertilizer with a relatively high C/N ratio and consequently a relatively low rate of nutrient release.
Kohl, Lukas; Philben, Michael; Edwards, Kate A; Podrebarac, Frances A; Warren, Jamie; Ziegler, Susan E
2018-02-01
Warmer climates have been associated with reduced bioreactivity of soil organic matter (SOM) typically attributed to increased diagenesis; the combined biological and physiochemical transformation of SOM. In addition, cross-site studies have indicated that ecosystem regime shifts, associated with long-term climate warming, can affect SOM properties through changes in vegetation and plant litter production thereby altering the composition of soil inputs. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming, however, remains poorly understood. To address this issue we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids analysis), and isotopic composition of plant litter and SOM across a well-constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. The observed climate effects on vascular plant litter chemistry, however, explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer relative to cooler forests. These results indicate that climate change induced decreases in the proportion of moss inputs not only impacts SOM chemistry but also increases the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils. © 2017 John Wiley & Sons Ltd.
Grant, T.A.; Madden, E.M.; Shaffer, T.L.; Pietz, P.J.; Berkey, G.B.; Kadrmas, N.J.
2006-01-01
The quantity and quality of northern mixed-grass prairie continues to decline because of conversion to agriculture, invasion of woody and exotic plants, and disruption of important ecological processes that shape grasslands. Declines in grassland bird populations in North Dakota, USA, have coincided with these largely anthropogenic alterations to prairie habitat. In grasslands of north-central and northwestern North Dakota, woody plants have increased due primarily to fire suppression, extirpation of bison (Bos bison), and widescale planting of tree shelter belts. In northern grasslands, effects of woody vegetation on survival of grassland birds are poorly understood, and conclusions are based mainly on studies conducted outside the region. We examined nest survival of clay-colored sparrows (Spizella pallida) and vesper sparrows (Pooecetes gramineus) relative to the distance nests were located from aspen (Populus tremuloides,) woodland edges and relative to other habitat features near the nest. Clay-colored and vesper sparrow nest survival was higher for nests located near woodland edges, nests with greater cover of Kentucky bluegrass (Poa pratensis), and nests more concealed by vegetation. Vesper sparrow nest survival increased as the percent cover of tall shrubs near the nest increased. Based on video-camera data, the 13-lined ground squirrel (Spermophilus tridecemlineatus,) was the most common predator of sparrow eggs and young. Thirteen-lined ground squirrels were more common far from woodland edges than near, and this pattern may, in part, explain clay-colored and vesper sparrow nest survival in relation to woodland edges. In contrast to our results, studies conducted in other grassland systems generally report lower nest survival for grassland birds nesting near trees and shrubs. This disparity in results demonstrates the need to identify specific nest predators and their distributions with respect to important habitat features because these data can be important in explaining-and perhaps predicting-patterns of nest predation.
Mateo, R.; Hoffman, D.J.
2001-01-01
Lead (Pb) exposure causes an increase in tissue lipid peroxides and variation in glutathione (GSH) concentration, which can be related to peroxidative damage of cell membranes in Pb poisoned animals. Species and individual variation in sensitivity to Pb poisoning among animals may be due to differential resistance to oxidative stress. We compared the effects of oxidative stress caused by Pb exposure (1.7, 414 and 828 ig/g of diet) for the first six weeks in growing young of two species of waterfowl, Canada geese (Branta canadensis) and mallards (Anas platyrhynchos), with the first species being possibly more sensitive to Pb poisoning based on previous field and laboratory observations. Blood and liver Pb concentrations increased more in mallards than in geese; this may be explained on the basis of body weight, being 3.2 times higher in geese, and hepatic metabolism where GSH-S-transferase activity is 2.9 fold higher in geese and presumably has a role in the binding of Pb to GSH and subsequent biliary excretion. In contrast, mallards showed higher hepatic levels of GSH and activities of GSH peroxidase (GPX) and GSH reductase (GR). Although both species showed an increase in hepatic GSH concentration with Pb exposure, the increase of lipid peroxidation with Pb exposure was more significant in geese. Within treatment groups, hepatic GSH concentrations were inversely related to liver Pb concentration in both species, which may correspond to the role of GSH in Pb excretion. Hepatic GSH was also inversely related to hepatic lipid peroxidation, but only in mallards and in agreement with the differences observed in GPX and GR activities. The lower resistance to lipid peroxidation of Canada geese may explain why birds of this species found dead in the field by Pb shot ingestion often have a lower number of shot in the gizzard and lower liver Pb concentrations than mallards.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mernild, Sebastian Haugard; Liston, Glen; Hasholt, Bent
2009-01-01
This observation and modeling study provides insights into runoff and sediment load exiting the Watson River drainage basin, Kangerlussuaq, West Greenland during a 30 year period (1978/79-2007/08) when the climate experienced increasing temperatures and precipitation. The 30-year simulations quantify the terrestrial freshwater and sediment output from part of the Greenland Ice Sheet (GrIS) and the land between the GrIS and the ocean, in the context of global warming and increasing GrIS surface melt. We used a snow-evolution modeling system (SnowModel) to simulate the winter accumulation and summer ablation processes, including runoff and surface mass balance (SMB), of the Greenland icemore » sheet. Observed sediment concentrations were related to observed runoff, producing a sediment-load time series. To a large extent, the SMB fluctuations could be explained by changes in net precipitation (precipitation minus evaporation and sublimation), with 8 out of 30 years having negative SMB, mainly because of relatively low annual net precipitation. The overall trend in net precipitation and runoff increased significantly, while 5MB increased insignificantly throughout the simulation period, leading to enhanced precipitation of 0.59 km{sup 3} w.eq. (or 60%), runoff of 0.43 km{sup 3} w.eq (or 54%), and SMB of 0.16 km3 w.eq. (or 86%). Runoff rose on average from 0.80 km{sup 3} w.eq. in 1978/79 to 1.23 km{sup 3} w.eq. in 2007/08. The percentage of catchment oudet runoff explained by runoff from the GrIS decreased on average {approx} 10%, indicating that catchment runoff throughout the simulation period was influenced more by precipitation and snowmelt events, and less by runoff from the GrIS. Average variations in the increasing Kangerlussuaq runoff from 1978/79 through 2007/08 seem to follow the overall variations in satellite-derived GrIS surface melt, where 64% of the variations in simulated runoff were explained by regional melt conditions on the GrIS. Throughout the simulation period, the sediment load varied from a minimum of 0.96 x 10{sup 6} t y{sup -1} in 1991/92 to a maximum of 3.52 x 10{sup 6} t y{sup -1} in 2006/07, showing an average increase of sediment load of 9.42 x 10{sup 5} t (or 72%) throughout the period.« less
Koopmans, M.P.; Rijpstra, W.I.C.; De Leeuw, J. W.; Lewan, M.D.; Damste, J.S.S.
1998-01-01
An immature (Ro=0.39%), S-rich (S(org)/C = 0.07), organic matter-rich (19.6 wt. % TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220 ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The alkylthiophene isomer distributions do not change significantly with increasing thermal maturation, indicating the applicability of alkylthiophenes as biomarkers at relatively high levels of thermal maturity. For a given carbon skeleton, the saturated hydrocarbon, alkylthiophenes and alkylbenzo[b]thiophenes are stable forms at relatively high temperatures, whereas the alkylsulfides are not stable. The large amount of alkylthiophenes produced relative to the alkanes may be explained by the large number of monosulfide links per carbon skeleton. These results are in good agreement with those obtained previously for an artificial maturation series of an immature S-rich sample from the Gessoso-solfifera Formation.An immature (Ro = 0.39%), S-rich (Sorg/C = 0.07), organic matter-rich (19.6 wt.% TOC) limestone from the Ghareb Formation (Upper Cretaceous) in Jordan was artificially matured by hydrous pyrolysis (200, 220, ..., 300??C; 72 h) to study the effect of progressive diagenesis and early catagenesis on the amounts and distributions of hydrocarbons, organic sulfur compounds and S-rich geomacromolecules. The use of internal standards allowed the determination of absolute amounts. With increasing thermal maturation, large amounts of alkanes and alkylthiophenes with predominantly linear carbon skeletons are generated from the kerogen. The alkylthiophene isomer distributions do not change significantly with increasing thermal maturation, indicating the applicability of alkylthiophenes as biomarkers at relatively high levels of thermal maturity. For a given carbon skeleton, the saturated hydrocarbon, alkylthiophene and alkylbenzo[b]thiophenes are stable forms at relatively high temperatures, whereas the alkylsulfides are not stable. The large amount of alkylthiophenes produced relative to the alkanes may be explained by the large number of monosulfide links per carbon skeleton. These results are in good agreement with those obtained previously for an artificial maturation series of an immature S-rich sample from the Gessoso-solfifera Formation.
Mullin, Lucy P; Sillett, Stephen C; Koch, George W; Tu, Kevin P; Antoine, Marie E
2009-08-01
This study examined relationships between foliar morphology and gas exchange characteristics as they vary with height within and among crowns of Sequoia sempervirens D. Don trees ranging from 29 to 113 m in height. Shoot mass:area (SMA) ratio increased with height and was less responsive to changes in light availability as height increased, suggesting a transition from light to water relations as the primary determinant of morphology with increasing height. Mass-based rates of maximum photosynthesis (A(max,m)), standardized photosynthesis (A(std,m)) and internal CO(2) conductance (g(i,m)) decreased with height and SMA, while the light compensation point, light saturation point, and mass and area-based rates of dark respiration (R(m)) increased with height and SMA. Among foliage from different heights, much of the variation in standardized photosynthesis was explained by variation in g(i,) consistent with increasing limitation of photosynthesis by internal conductance in foliage with higher SMA. The syndrome of lower internal and stomatal conductance to CO(2) and higher respiration may contribute to reductions in upper crown growth efficiency with increasing height in S. sempervirens trees.
What explains the relation between family poverty and childhood depressive symptoms?
Tracy, Melissa; Zimmerman, Frederick J; Galea, Sandro; McCauley, Elizabeth; Stoep, Ann Vander
2008-10-01
The relation between low socioeconomic status (SES) and depression has been well documented in adult populations. A number of studies suggest that family SES may be associated with depression among children and adolescents as well, although the evidence is mixed. We assessed the relation between family income and depressive symptoms among 457 children aged 11-13 years and examined pathways that may explain this relation. In-person interviews of children and their caregivers were conducted, including assessment of family income and administration of the Computer-based Diagnostic Interview Schedule for Children (C-DISC). Family income was significantly associated with depressive symptoms, with children in the lowest income group (<$35,000) reporting a mean of 8.12 symptoms compared to 6.27 symptoms in the middle income group ($35,000-$74,999) and 5.13 symptoms in the highest income group (> or = $75,000; p<0.001). Controlling for the number of stressful life events experienced in the past 6 months attenuated the effect of low family income on depressive symptoms by 28%. Indicators of the family environment explained 45% and neighborhood median household income and aggravated assault rate explained 12% of the relation. The family environment, including parental divorce or separation and perceived parental support, appears to explain most of the relation between low family income and childhood depressive symptoms. Further exploration of the pathways between family SES and depression may suggest potential interventions to reduce the occurrence and persistence of depressive symptoms in children.
Humidity trends imply increased sensitivity to clouds in a warming Arctic
Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; ...
2015-12-10
Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Ourmore » findings explain observed seasonal and regional variability in Arctic CRE of order 10Wm 2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1–5Wm 2 in autumn and winter, which are projected to reach 5–15Wm 2 by 2050, implying increased sensitivity of the surface to clouds.« less
Humidity trends imply increased sensitivity to clouds in a warming Arctic.
Cox, Christopher J; Walden, Von P; Rowe, Penny M; Shupe, Matthew D
2015-12-10
Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m(-2). With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1-5 W m(-2) in autumn and winter, which are projected to reach 5-15 W m(-2) by 2050, implying increased sensitivity of the surface to clouds.
Humidity trends imply increased sensitivity to clouds in a warming Arctic
Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; Shupe, Matthew D.
2015-01-01
Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m−2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1–5 W m−2 in autumn and winter, which are projected to reach 5–15 W m−2 by 2050, implying increased sensitivity of the surface to clouds. PMID:26657324
[Type 2 Diabetes and Dietary Patterns 1961 to 2009: Some Social Determinants in Mexico].
Moreno-Altamirano, Laura; Silberman, Martín; Hernández-Montoya, Dewi; Capraro, Santiago; Soto-Estrada, Guadalupe; García-García, Juan José; Sandoval-Bosh, Elvira
2015-01-01
In order to analyze whether the increase in mortality from diabetes in Mexico is related to changes in eating patterns over the period 1961 to 2009, and if they in turn could be explained in the Mexican socioeconomic context, we conducted an ecological study with information from the Food Balance Sheets FAO. A cluster analysis was performed to shape eating patterns (three) and some socioeconomic variables were analyzed. It was observed that the energy derived from cereals and legumes (beans) was significantly reduced, and simultaneously, energy from sugars, animal foods, and vegetable fats had a significant increase. Various socioeconomic conditions may have favored changes in diet and increased mortality from diabetes. These conditions are: trade liberalization, low growth, rising inequality and informal work, declining agriculture, falling real wages in relation to the value of what is called the “basic food and non-food baskets”, increasing prices of healthy food,low cost of processed foods and beverages, and the lack of control in the food market.
Cheung, Y B
1998-03-01
In view of the rising divorce rates, the impact of divorce on health has an increasing importance in public health. The differentials in health between the married and the divorced may be explained by 'marital selection' and 'marital protection'. Using longitudinal data from a study of the 1958 British birth cohort, factors that select people into divorce were identified from the areas of socio-economic status, health, and attractiveness, which included physical attractiveness, health-related behaviour and temperament. Evidence for both positive and adverse selection is found. The different sets of selection factors for females and males appear to be in line with gender role expectations. The health differentials between married and divorced men were weak and can be explained away by the selection factors. Having controlled for the selection effects, there were still significant associations between divorce and physical and psychological health in women. Though these unexplained differentials cannot be definitely interpreted as the consequences of marital dissolution, this interpretation remains plausible.
NASA Astrophysics Data System (ADS)
Griesse-Nascimento, Sarah; Bridger, Joshua; Brown, Keith; Westervelt, Robert
2011-03-01
Interactive computer simulations increase students' understanding of difficult concepts and their ability to explain complex ideas. We created a module of eight interactive programs and accompanying lesson plans for teaching the fundamental concepts of Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) that we call interactive NMR (iNMR). We begin with an analogy between nuclear spins and metronomes to start to build intuition about the dynamics of spins in a magnetic field. We continue to explain T1, T2, and pulse sequences with the metronome analogy. The final three programs are used to introduce and explain the Magnetic Resonance Switch, a recent diagnostic technique based on NMR. A modern relevant application is useful to generate interest in the topic and confidence in the students' ability to apply their knowledge. The iNMR module was incorporated into a high school AP physics class. In a preliminary evaluation of implementation, students expressed enthusiasm and demonstrated enhanced understanding of the material relative to the previous year. Funded by NSF PHY-0646094 grant.
Graham, Dan J; Lucas-Thompson, Rachel G; Mueller, Megan P; Jaeb, Melanie; Harnack, Lisa
2017-04-01
The present study investigated whether parent/child pairs would select more healthful foods when: (i) products were labelled with front-of-package (FOP) nutrition labels relative to packages without labels; (ii) products were labelled with colour-coded Multiple Traffic Light (MTL) FOP labels relative to monochromatic Facts up Front (FuF) FOP labels; and (iii) FOP labels were explained via in-aisle signage v. unexplained. Participants were randomly assigned to one of five conditions: (i) FuF labels with in-aisle signs explaining the labels; (ii) FuF labels, no signage; (iii) MTL labels with in-aisle signage; (iv) MTL labels, no signage; (v) control group, no labels/signage. Saturated fat, sodium, sugar and energy (calorie) content were compared across conditions. The study took place in a laboratory grocery aisle. Parent/child pairs (n 153) completed the study. Results did not support the hypothesis that MTL labels would lead to more healthful choices than FuF labels. The presence of FOP labels did little to improve the healthfulness of selected foods, with few exceptions (participants with v. without access to FOP labels selected lower-calorie cereals, participants with access to both FOP labels and in-aisle explanatory signage selected products with less saturated fat v. participants without explanatory signage). Neither MTL nor FuF FOP labels led to food choices with significantly lower saturated fat, sodium or sugar. In-aisle signs explaining the FOP labels were somewhat helpful to consumers in making more healthful dietary decisions. New FOP labelling programmes could benefit from campaigns to increase consumer awareness and understanding of the labels.
The trait contribution to wood decomposition rates of 15 Neotropical tree species.
van Geffen, Koert G; Poorter, Lourens; Sass-Klaassen, Ute; van Logtestijn, Richard S P; Cornelissen, Johannes H C
2010-12-01
The decomposition of dead wood is a critical uncertainty in models of the global carbon cycle. Despite this, relatively few studies have focused on dead wood decomposition, with a strong bias to higher latitudes. Especially the effect of interspecific variation in species traits on differences in wood decomposition rates remains unknown. In order to fill these gaps, we applied a novel method to study long-term wood decomposition of 15 tree species in a Bolivian semi-evergreen tropical moist forest. We hypothesized that interspecific differences in species traits are important drivers of variation in wood decomposition rates. Wood decomposition rates (fractional mass loss) varied between 0.01 and 0.31 yr(-1). We measured 10 different chemical, anatomical, and morphological traits for all species. The species' average traits were useful predictors of wood decomposition rates, particularly the average diameter (dbh) of the tree species (R2 = 0.41). Lignin concentration further increased the proportion of explained inter-specific variation in wood decomposition (both negative relations, cumulative R2 = 0.55), although it did not significantly explain variation in wood decomposition rates if considered alone. When dbh values of the actual dead trees sampled for decomposition rate determination were used as a predictor variable, the final model (including dead tree dbh and lignin concentration) explained even more variation in wood decomposition rates (R2 = 0.71), underlining the importance of dbh in wood decomposition. Other traits, including wood density, wood anatomical traits, macronutrient concentrations, and the amount of phenolic extractives could not significantly explain the variation in wood decomposition rates. The surprising results of this multi-species study, in which for the first time a large set of traits is explicitly linked to wood decomposition rates, merits further testing in other forest ecosystems.
Teachers mathematical communication profile in explaining subject matter
NASA Astrophysics Data System (ADS)
Umami, Rohmatul; Budayasa, I. Ketut; Suwarsono, St.
2017-12-01
This study aimed to see a teachers mathematical communication profile in explaining a subject matter. It is a qualitative research. A high-school junior teacher (i.e., a teacher with 1- to 5-year experience) teaching mathematics at X-Social Class was selected as the subject of this study. The data was collected by observing the teachers mathematical communication in explaining a given material (i.e., the rule of sine) in class and an in-depth interview would be organized respectively. The result showed that the junior teacher explained the subject matter in systematic, complete, fluent, and centered manner. In this case, she began with reminding students on the previous material related to the current material to be learned, informing the current learning objectives, and finally delivering the subject matter. To support her explanation, the teacher also provided some related information, led the students attention into the given material by asking them particular related questions, and did not use any confusing terms. However, the study found that some of high-school teachers still used less appropriate language in explaining materials.
Brouwer, Rachel M; Panizzon, Matthew S; Glahn, David C; Hibar, Derrek P; Hua, Xue; Jahanshad, Neda; Abramovic, Lucija; de Zubicaray, Greig I; Franz, Carol E; Hansell, Narelle K; Hickie, Ian B; Koenis, Marinka M G; Martin, Nicholas G; Mather, Karen A; McMahon, Katie L; Schnack, Hugo G; Strike, Lachlan T; Swagerman, Suzanne C; Thalamuthu, Anbupalam; Wen, Wei; Gilmore, John H; Gogtay, Nitin; Kahn, René S; Sachdev, Perminder S; Wright, Margaret J; Boomsma, Dorret I; Kremen, William S; Thompson, Paul M; Hulshoff Pol, Hilleke E
2017-09-01
Structural brain changes that occur during development and ageing are related to mental health and general cognitive functioning. Individuals differ in the extent to which their brain volumes change over time, but whether these differences can be attributed to differences in their genotypes has not been widely studied. Here we estimate heritability (h 2 ) of changes in global and subcortical brain volumes in five longitudinal twin cohorts from across the world and in different stages of the lifespan (N = 861). Heritability estimates of brain changes were significant and ranged from 16% (caudate) to 42% (cerebellar gray matter) for all global and most subcortical volumes (with the exception of thalamus and pallidum). Heritability estimates of change rates were generally higher in adults than in children suggesting an increasing influence of genetic factors explaining individual differences in brain structural changes with age. In children, environmental influences in part explained individual differences in developmental changes in brain structure. Multivariate genetic modeling showed that genetic influences of change rates and baseline volume significantly overlapped for many structures. The genetic influences explaining individual differences in the change rate for cerebellum, cerebellar gray matter and lateral ventricles were independent of the genetic influences explaining differences in their baseline volumes. These results imply the existence of genetic variants that are specific for brain plasticity, rather than brain volume itself. Identifying these genes may increase our understanding of brain development and ageing and possibly have implications for diseases that are characterized by deviant developmental trajectories of brain structure. Hum Brain Mapp 38:4444-4458, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Alcohol, wine and platelet function.
Ruf, Jean-Claude
2004-01-01
Epidemiological studies have demonstrated an inverse correlation between moderate wine and alcohol consumption and morbidity and mortality from coronary heart disease. The protective effect has been associated with an increase in the plasma level of HDL cholesterol, as it is well recognized that plasma HDL is inversely correlated with CHD. In addition, it has become evident that blood platelets contribute to the rate of development of atherosclerosis and CHD through several mechanisms. In recent studies it has been shown that the level of HDL cholesterol can explain only 50% of the protective effect of alcoholic beverages; the other 50% may be partly related to a decrease in platelet activity. This anti-platelet activity of wine is explained by ethanol but also by the polyphenolic components with which red wines are richly endowed. Several studies carried out on humans and animals have shown that wine phenolics could exert their effects by reducing prostanoid synthesis from arachidonate. In addition, it has been suggested that wine phenolics could reduce platelet activity mediated by nitric oxide. Moreover, wine phenolics increase vitamin E levels while decreasing the oxidation of platelets submitted to oxidative stress. However, a rebound phenomenon of hyperaggregability is observed after an acute alcohol consumption which is not observed with wine consumption. This protection afforded by wine has been duplicated in animals with grape phenolics added to alcohol. The rebound phenomenon may explain ischemic strokes or sudden deaths known to occur after episodes of drunkenness. It appears that wine, and wine phenolics in particular, could have a more significant inhibitory effect on platelet aggregation and could explain, in part, the hypothesis that red wine is more protective against atherosclerosis and coronary heart disease.
Object Relations and the Development of Values.
ERIC Educational Resources Information Center
Gazda, George M.; Sedgwick, Charlalee
1990-01-01
Claims acquisition of values is related to successes and failures of early relationships. Describes steps person goes through in making identifications, explaining steps that move person toward construction of value system. Refers to works of Heinz Kohut to explain how child's idealizing has within it necessary components for child's growth in…
Nicodemus, Kristin K; Hargreaves, April; Morris, Derek; Anney, Richard; Gill, Michael; Corvin, Aiden; Donohoe, Gary
2014-07-01
We investigated the variation in neuropsychological function explained by risk alleles at the psychosis susceptibility gene ZNF804A and its interacting partners using single nucleotide polymorphisms (SNPs), polygenic scores, and epistatic analyses. Of particular importance was the relative contribution of the polygenic score vs epistasis in variation explained. To (1) assess the association between SNPs in ZNF804A and the ZNF804A polygenic score with measures of cognition in cases with psychosis and (2) assess whether epistasis within the ZNF804A pathway could explain additional variation above and beyond that explained by the polygenic score. Patients with psychosis (n = 424) were assessed in areas of cognitive ability impaired in schizophrenia including IQ, memory, attention, and social cognition. We used the Psychiatric GWAS Consortium 1 schizophrenia genome-wide association study to calculate a polygenic score based on identified risk variants within this genetic pathway. Cognitive measures significantly associated with the polygenic score were tested for an epistatic component using a training set (n = 170), which was used to develop linear regression models containing the polygenic score and 2-SNP interactions. The best-fitting models were tested for replication in 2 independent test sets of cases: (1) 170 individuals with schizophrenia or schizoaffective disorder and (2) 84 patients with broad psychosis (including bipolar disorder, major depressive disorder, and other psychosis). Participants completed a neuropsychological assessment battery designed to target the cognitive deficits of schizophrenia including general cognitive function, episodic memory, working memory, attentional control, and social cognition. Higher polygenic scores were associated with poorer performance among patients on IQ, memory, and social cognition, explaining 1% to 3% of variation on these scores (range, P = .01 to .03). Using a narrow psychosis training set and independent test sets of narrow phenotype psychosis (schizophrenia and schizoaffective disorder), broad psychosis, and control participants (n = 89), the addition of 2 interaction terms containing 2 SNPs each increased the R2 for spatial working memory strategy in the independent psychosis test sets from 1.2% using the polygenic score only to 4.8% (P = .11 and .001, respectively) but did not explain additional variation in control participants. These data support a role for the ZNF804A pathway in IQ, memory, and social cognition in cases. Furthermore, we showed that epistasis increases the variation explained above the contribution of the polygenic score.
García-Espinosa, Victoria; Curcio, Santiago; Marotta, Marco; Castro, Juan M; Arana, Maite; Peluso, Gonzalo; Chiesa, Pedro; Giachetto, Gustavo; Bia, Daniel; Zócalo, Yanina
2016-10-01
The aims were to determine whether children's high peripheral blood pressure states (HBP) are associated with increased central aortic blood pressure (BP) and to characterize hemodynamic and vascular changes associated with HBP in terms of changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR) and net and relative contributions of reflected waves to the aortic pulse amplitude. We included 154 subjects (mean age 11; range 4-16 years) assigned to one of two groups: normal peripheral BP (NBP, n = 101), defined as systolic and diastolic BP < 90th percentile, or high BP (HBP, n = 53), defined as average systolic and/or diastolic BP levels ≥90th percentile (curves for sex, age and body height). The HBP group included children with hypertensive and pre-hypertensive BP levels. After a first analysis, groups were compared excluding obese and dyslipidemic children. Peripheral and central aortic BP, PWV and pulse wave-derived parameters (augmentation index, forward and backward wave components' amplitude) were measured using gold-standard techniques, applanation tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). Independent of the presence of dyslipidemia and/or obesity, aortic systolic and pulse BP were higher in HBP than in NBP children. The increase in central BP could not be explained by an increase in the relative contribution of reflections to the aortic pressure wave, higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP would be explained by an increase in the amplitude of both incident and reflected wave components.
Lane, E L; Cheetham, S; Jenner, P
2008-01-01
The monoamine uptake inhibitor BTS 74 398 induces ipsilateral circling in 6-hydroxydopamine (6-OHDA) lesioned rats without induction of abnormal motor behaviours associated with L-dopa administration. We examined whether this was reflected in the expression of peptide mRNA in the direct and indirect striatal output pathways.6-OHDA lesioning of the nigrostriatal pathway increased striatal expression of PPE-A mRNA and decreased levels of PPT mRNA with PPE-B mRNA expression remaining unchanged. Acute L-dopa administration normalised PPE-A mRNA and elevated PPT mRNA while PPE-B mRNA expression remained unchanged. Acute administration of BTS 74 398 did not alter striatal peptide mRNA levels. Following chronic treatment with L-dopa, PPE-A mRNA expression in the lesioned striatum continued to be normalised and PPT mRNA was increased compared to the intact side. PPE-B mRNA expression was also markedly increased relative to the non-lesioned striatum. Chronic BTS 74 398 administration did not alter mRNA expression in the 6-OHDA lesioned striatum although small increases in PPT mRNA expression in the intact and sham lesioned striatum were observed. The failure of BTS 74 398 to induce changes in striatal neuropeptide mRNA correlated with its failure to induce abnormal motor behaviours or behavioural sensitisation but does not explain how it produces a reversal of motor deficits. An action in another area of the brain appears likely and may explain the subsequent failure of BTS 74 398 and related compounds to exert anti-parkinsonian actions in man.
Tompkins, Adrian M; Larsen, Laragh; McCreesh, Nicky; Taylor, David
2016-03-31
Malaria case statistics were analysed for the period 1926 to 1960 to identify inter-annual variations in malaria cases for the Uganda Protectorate. The analysis shows the mid-to-late 1930s to be a period of increased reported cases. After World War II, malaria cases trend down to a relative minimum in the early 1950s, before increasing rapidly after 1953 to the end of the decade. Data for the Western Province confirm these national trends, which at the time were attributed to a wide range of causes, including land development and management schemes, population mobility, interventions and misdiagnosis. Climate was occasionally proposed as a contributor to enhanced case numbers, and unusual precipitation patterns were held responsible; temperature was rarely, if ever, considered. In this study, a dynamical malaria model was driven with available precipitation and temperature data from the period for five stations located across a range of environments in Uganda. In line with the historical data, the simulations produced relatively enhanced transmission in the 1930s, although there is considerable variability between locations. In all locations, malaria transmission was low in the late 1940s and early 1950s, steeply increasing after 1954. Results indicate that past climate variability explains some of the variations in numbers of reported malaria cases. The impact of multiannual variability in temperature, while only on the order of 0.5°C, was sufficient to drive some of the trends observed in the statistics and thus the role of climate was likely underestimated in the contemporary reports. As the elimination campaigns of the 1960s followed this partly climate-driven increase in malaria, this emphasises the need to account for climate when planning and evaluating intervention strategies.
Exercising self-control increases approach motivation.
Schmeichel, Brandon J; Harmon-Jones, Cindy; Harmon-Jones, Eddie
2010-07-01
The present research tested the hypothesis that exercising self-control causes an increase in approach motivation. Study 1 found that exercising (vs. not exercising) self-control increases self-reported approach motivation. Study 2a identified a behavior--betting on low-stakes gambles--that is correlated with approach motivation but is relatively uncorrelated with self-control, and Study 2b observed that exercising self-control temporarily increases this behavior. Last, Study 3 found that exercising self-control facilitates the perception of a reward-relevant symbol (i.e., a dollar sign) but not a reward-irrelevant symbol (i.e., a percent sign). Altogether, these results support the hypothesis that exercising self-control temporarily increases approach motivation. Failures of self-control that follow from prior efforts at self-control (i.e., ego depletion) may be explained in part by increased approach motivation.
NASA Technical Reports Server (NTRS)
Asoka, Akarsh; Gleeson, Tom; Wada, Yoshihide; Mishra, Vimal
2017-01-01
The depletion of groundwater resources threatens food and water security in India. However, the relative influence of groundwater pumping and climate variability on groundwater availability and storage remains unclear. Here we show from analyses of satellite and local well data spanning the past decade that long-term changes in monsoon precipitation are driving groundwater storage variability in most parts of India either directly by changing recharge or indirectly by changing abstraction. We find that groundwater storage has declined in northern India at the rate of 2 cm/yr and increased by 1 to 2 cm/yr in southern India between 2002 and 2013. We find that a large fraction of the total variability in groundwater storage in north-central and southern India can be explained by changes in precipitation. Groundwater storage variability in northwestern India can be explained predominantly by variability in abstraction for irrigation, which is in turn influenced by changes in precipitation. Declining precipitation in northern India is linked to Indian Ocean warming, suggesting a previously unrecognized teleconnection between ocean temperatures and groundwater storage.
Hochard, Kevin D; Heym, Nadja; Townsend, Ellen
2017-06-01
Heightened arousal significantly interacts with acquired capability to predict suicidality. We explore this interaction with insomnia and nightmares independently of waking state arousal symptoms, and test predictions of the Interpersonal Theory of Suicide (IPTS) and Escape Theory in relation to these sleep arousal symptoms. Findings from our e-survey (n = 540) supported the IPTS over models of Suicide as Escape. Sleep-specific measurements of arousal (insomnia and nightmares) showed no main effect, yet interacted with acquired capability to predict increased suicidality. The explained variance in suicidality by the interaction (1%-2%) using sleep-specific measures was comparable to variance explained by interactions previously reported in the literature using measurements composed of a mix of waking and sleep state arousal symptoms. Similarly, when entrapment (inability to escape) was included in models, main effects of sleep symptoms arousal were not detected yet interacted with entrapment to predict suicidality. We discuss findings in relation to treatment options suggesting that sleep-specific interventions be considered for the long-term management of at-risk individuals. © 2016 The American Association of Suicidology.
Coulson, Neil S; Ferguson, Melanie A; Henshaw, Helen; Heffernan, Eithne
2016-07-01
In recent years, there has been an increase in the application of behavioural models, such as social cognition models, to the promotion of hearing health. Despite this, there exists a well-developed body of literature that suggests such models may fail to consistently explain reliable amounts of variability in human behaviours. This paper provides a summary of this research across selected models of health-related behaviour, outlining the current state of the evidence. Recent work in the field of behaviour change is presented together with commentary on the design and reporting of behaviour change interventions. We propose that attempts to use unreliable models to explain and predict hearing health behaviours should now be replaced by work which integrates the latest in behaviour change science, such as the Behaviour Change Wheel and Theoretical Domains Framework.
Prediction of episodic acidification in North-eastern USA: An empirical/mechanistic approach
Davies, T.D.; Tranter, M.; Wigington, P.J.; Eshleman, K.N.; Peters, N.E.; Van Sickle, J.; DeWalle, David R.; Murdoch, Peter S.
1999-01-01
Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the North-eastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The pre-episode ANC is used to index the antecedent condition, and the stream flow increase reflects how much the relative contributions of sources of waters change during the episode. As much as 92% of the total variation in the minimum ANC in individual catchments can be explained (with levels of explanation >70% for nine of the 13 streams) by a multiple linear regression model that includes pre-episode ANC and change in discharge as independent variable. The predictive scheme is demonstrated to be regionally robust, with the regional variance explained ranging from 77 to 83%. The scheme is not successful for each ERP stream, and reasons are suggested for the individual failures. The potential for applying the predictive scheme to other watersheds is demonstrated by testing the model with data from the Panola Mountain Research Watershed in the South-eastern United States, where the variance explained by the model was 74%. The model can also be utilized to assess 'chemically new' and 'chemically old' water sources during acidification episodes.Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the Northeastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The pre-episode ANC is used to index the antecedent condition, and the stream flow increase reflects how much the relative contributions of sources of waters change during the episode. As much as 92% of the total variation in the minimum ANC in individual catchments can be explained (with levels of explanation >70% for nine of the 13 streams) by a multiple linear regression model that includes pre-episode ANC and change in discharge as independent variables. The predictive scheme is demonstrated to be regionally robust, with the regional variance explained ranging from 77 to 83%. The scheme is not successful for each ERP stream, and reasons are suggested for the individual failures. The potential for applying the predictive scheme to other watersheds is demonstrated by testing the model with data from the Panola Mountain Research Watershed in the South-eastern United States, where the variance explained by the model was 74%. The model can also be utilized to assess `chemically new' and `chemically old' water sources during acidification episodes.
The Marine Corps Physical Fitness Test: The Need to Replace it with a Combat Fitness Test
2008-02-19
unforeseen emergencies.”1 Crossfit , a website-based workout program, has popularized the en vogue, yet relatively old concept of “functional fitness...Sports; 1996. <http://www.cdc.gov/nccdphp/sgr/sgr.htm> 2 Greg Glassman, “What is Fitness?” Crossfit Journal, October 2002, 1-2. 3 human...short, intense workouts aimed at increasing power, speed, and strength. Additionally, Crossfit explains the crossover between the three pathways
Greater effect of increasing shrub height on winter versus summer soil temperature
NASA Astrophysics Data System (ADS)
Paradis, Mélissa; Lévesque, Esther; Boudreau, Stéphane
2016-08-01
Shrub expansion is increasingly observed in arctic and subarctic environments. The development of shrub structure may significantly impact the abiotic environment at the local scale. Our objective was to reconstruct the development of the vertical structure of Betula glandulosa Michx. and to evaluate its effects on winter and summer soil temperature and on snow depth. Stratified sampling of the shrub revealed that shrub biomass distribution followed a similar pattern in stands of contrasting heights. Woody biomass was maximal in the lower stratum and relatively stable in the intermediate strata, while the foliar biomass tracked the vertical development of the shrub structure. Dendrochronological analysis revealed that shrub stands are relatively young; most of the dominant stems started their development after 1990. Shrub height was positively associated with both the dominant stem age and its vertical growth rate. Temperature differences among sites were greater during winter (ca 10 °C) than during summer (ca 2 °C), while the sum of freezing degree-days varied from 680 °C to 2125 °C. Shrub height was the most plausible variable explaining snow depth, winter ground level temperature and the sum of freezing degree-days. However, woody biomass in the 30-40 cm strata best explained summer ground level temperature. Our results suggest that the development of a shrub structure will have far-reaching consequences on the abiotic environment of subarctic ecosystems.
A comparison of cat-related risk perceptions and tolerance for outdoor cats in Florida and Hawaii.
Wald, Dara M; Lohr, Cheryl A; Lepczyk, Christopher A; Jacobson, Susan K; Cox, Linda J
2016-12-01
Risk perceptions and attitudes toward animals often explain tolerance for wildlife and management preferences. However, little is understood about how these relationships vary across different geographic regions and stakeholder groups. To address this gap in knowledge, we compared differences in acceptance capacity, risk perceptions, perceived enjoyment from outdoor cats, and experiences with outdoor cats among 3 groups (general public, conservation community, and animal-welfare community) in Hawaii and Florida, two states with large conservation challenges. We combined independently collected data from Florida and Hawaii, to determine how perception of the risks presented by outdoor cats, group membership, and state of residence influenced people's tolerance for outdoor cats. Florida respondents were significantly more tolerant of outdoor cats and less concerned about cat-related risks than Hawaii respondents (p < 0.05). In both states, animal-welfare group members reported greater enjoyment seeing cats and perceived a smaller increase in the cat population and lower levels of risk than other groups (p < 0.05). All groups exhibited similar relationships between acceptance capacity and enjoyment and the perceived increase in the cat population. Our results suggest public tolerance for cats varied due to the influence of local or geographical concerns, but that strongly held beliefs, risk perceptions, and feelings about cats explained more of the variance in stakeholder tolerance. © 2016 Society for Conservation Biology.
Lehto, Elviira; Ray, Carola; Haukkala, Ari; Yngve, Agneta; Thorsdottir, Inga; Roos, Eva
2015-12-01
We studied the factors that predict liking for vegetables and preference for a variety of vegetables among schoolchildren. Additionally, we examined if there were gender differences in the predictors that explain the hypothesized higher scores in liking vegetables and preferences among girls. The data from the PRO GREENS project included 424 Finnish children (response rate 77%) aged 11 to 12. The children completed validated measures about social and environmental factors related to their liking for vegetables and preferences both at baseline 2009 and follow-up 2010. The associations were examined with regression and mediation analyses. The strongest predictors of both girls' and boys' liking and preferences were higher levels of eating vegetables together with the family, previous vegetable intake and a lower level of perceived barriers. Liking was additionally predicted by a lower level of parental demand that their child should eat vegetables. Girls reported higher levels of liking and preferences in the follow-up. This gender difference was mainly explained by girls' lower level of perceived barriers related to vegetable intake and girls' higher previous vegetable intake. Interventions that aim to increase the low vegetable intake among boys by increasing their liking for vegetables and preference for a variety of vegetables could benefit from targeting perceived barriers, namely boys' perception and values concerning the consumption of vegetables. Copyright © 2015 Elsevier Ltd. All rights reserved.
Status threat, not economic hardship, explains the 2016 presidential vote.
Mutz, Diana C
2018-05-08
This study evaluates evidence pertaining to popular narratives explaining the American public's support for Donald J. Trump in the 2016 presidential election. First, using unique representative probability samples of the American public, tracking the same individuals from 2012 to 2016, I examine the "left behind" thesis (that is, the theory that those who lost jobs or experienced stagnant wages due to the loss of manufacturing jobs punished the incumbent party for their economic misfortunes). Second, I consider the possibility that status threat felt by the dwindling proportion of traditionally high-status Americans (i.e., whites, Christians, and men) as well as by those who perceive America's global dominance as threatened combined to increase support for the candidate who emphasized reestablishing status hierarchies of the past. Results do not support an interpretation of the election based on pocketbook economic concerns. Instead, the shorter relative distance of people's own views from the Republican candidate on trade and China corresponded to greater mass support for Trump in 2016 relative to Mitt Romney in 2012. Candidate preferences in 2016 reflected increasing anxiety among high-status groups rather than complaints about past treatment among low-status groups. Both growing domestic racial diversity and globalization contributed to a sense that white Americans are under siege by these engines of change. Copyright © 2018 the Author(s). Published by PNAS.
Height-income association in developing countries: Evidence from 14 countries.
Patel, Pankaj C; Devaraj, Srikant
2017-12-28
The purpose of this study was to assess whether the height-income association is positive in developing countries, and whether income differences between shorter and taller individuals in developing countries are explained by differences in endowment (ie, taller individuals have a higher income than shorter individuals because of characteristics such as better social skills) or due to discrimination (ie, shorter individuals have a lower income despite having comparable characteristics). Instrumental variable regression, Oaxaca-Blinder decomposition, quantile regression, and quantile decomposition analyses were applied to a sample of 45 108 respondents from 14 developing countries represented in the Research on Early Life and Aging Trends and Effects (RELATE) study. For a one-centimeter increase in country- and sex-adjusted median height, real income adjusted for purchasing power parity increased by 1.37%. The income differential between shorter and taller individuals was explained by discrimination and not by differences in endowments; however, the effect of discrimination decreased at higher values of country- and sex-adjusted height. Taller individuals in developing countries may realize higher income despite having characteristics similar to those of shorter individuals. © 2017 Wiley Periodicals, Inc.
School victimization and substance use among lesbian, gay, bisexual, and transgender adolescents.
Huebner, David M; Thoma, Brian C; Neilands, Torsten B
2015-07-01
Lesbian, gay, bisexual, and transgender (LGBT) adolescents are at increased risk for substance use, relative to their heterosexual counterparts. Although previous research has demonstrated that experiences of anti-LGBT harassment, discrimination, and victimization may explain some of this disparity, little is known about the mechanisms whereby such mistreatment leads to substance abuse. This study aimed to examine whether mechanisms suggested by the Social Development Model might explain the links between school-based victimization and substance use in this population. Five hundred and four ethnically diverse LGBT adolescents ages 14-19 reported their experiences with school victimization, substance abuse, school bonding, and deviant peer group affiliation. Anti-LGBT victimization in school was associated with substance abuse, and although causality cannot be established, structural equation modeling confirmed that the data are consistent with a theoretical model in which this association was mediated by increased affiliation with deviant peers. Preventive interventions for LGBT adolescents must not only attempt to make schools safer for these youth, but also help keep them engaged in healthy peer groups when they are confronted with mistreatment in school.
Baum-Snow, Nathaniel; Pavan, Ronni
2013-01-01
Between 1979 and 2007 a strong positive monotonic relationship between wage inequality and city size has developed. This paper investigates the links between this emergent city size inequality premium and the contemporaneous nationwide increase in wage inequality. After controlling for the skill composition of the workforce across cities of different sizes, we show that at least 23 percent of the overall increase in the variance of log hourly wages in the United States from 1979 to 2007 is explained by the more rapid growth in the variance of log wages in larger locations relative to smaller locations. This influence occurred throughout the wage distribution and was most prevalent during the 1990s. More rapid growth in within skill group inequality in larger cities has been by far the most important force driving these city size specific patterns in the data. Differences in the industrial composition of cities of different sizes explain up to one-third of this city size effect. These results suggest an important role for agglomeration economies in generating changes in the wage structure during the study period. PMID:24954958
School Victimization and Substance Use among Lesbian, Gay, Bisexual, and Transgender Adolescents
Huebner, David M.; Thoma, Brian C.; Neilands, Torsten B.
2014-01-01
Lesbian, gay, bisexual, and transgender (LGBT) adolescents are at increased risk for substance use, relative to their heterosexual counterparts. Although previous research has demonstrated that experiences of anti-LGBT harassment, discrimination, and victimization may explain some of this disparity, little is known about the mechanisms whereby such mistreatment leads to substance abuse. This study aimed to examine whether mechanisms suggested by the Social Development Model might explain the links between school-based victimization and substance use in this population. Five hundred and four ethnically diverse LGBT adolescents ages 14–19 reported their experiences with school victimization, substance abuse, school bonding, and deviant peer group affiliation. Anti-LGBT victimization in school was associated with substance abuse, and although causality cannot be established, structural equation modeling confirmed that the data are consistent with a theoretical model in which this association was mediated by increased affiliation with deviant peers. Preventive interventions for LGBT adolescents must not only attempt to make schools safer for these youth, but also help keep them engaged in healthy peer groups when they are confronted with mistreatment in school. PMID:25529390
NASA Astrophysics Data System (ADS)
Maluck, Julian; Donner, Reik V.
2017-02-01
International trade has grown considerably during the process of globalization. Complex supply chains for the production of goods have resulted in an increasingly connected International Trade Network (ITN). Traditionally, direct trade relations between industries have been regarded as mediators of supply and demand spillovers. With increasing network connectivity the question arises if higher-order relations become more important in explaining a national sector's susceptibility to supply and demand changes of its trading partner. In this study we address this question by investigating empirically to what extent the topological properties of the ITN provide information about positive correlations in the production of two industry sectors. We observe that although direct trade relations between industries serve as important indicators for correlations in the industries' value added growth, opportunities of substitution for required production inputs as well as second-order trade relations cannot be neglected. Our results contribute to a better understanding of the relation between trade and economic productivity and can serve as a basis for the improvement of crisis spreading models that evaluate contagion threats in the case of a node's failure in the ITN.
Decadal variations in diatoms and dinoflagellates on the inner shelf of the East China Sea, China
NASA Astrophysics Data System (ADS)
Abate, Rediat; Gao, Yahui; Chen, Changping; Liang, Junrong; Mu, Wenhua; Kifile, Demeke; Chen, Yanghang
2017-11-01
Diatoms and dinoflagellates are two major groups of phytoplankton that flourish in the oceans, particularly in coastal zone and upwelling systems, and their contrasting production have been reported in several world seas. However, this information is not available in the coastal East China Sea (ECS). Thus, to investigate and compare the decadal trends in diatoms and dinoflagellates, a sediment core, 47 cm long, was collected from the coastal zone of the ECS. Sediment chlorophyll- a (Chl- a), phytoplankton-group specific pigment signatures of diatoms and dinoflagellates, and diatom valve concentrations were determined. The sediment core covered the period from 1961 to 2011 AD. The chlorophyll- a contents ranged from 2.32 to 73 µg/g dry sediment (dw) and averaged 9.81 µg/g dw. Diatom absolute abundance ranged from 29152 to 177501 valve/gram (v/g) dw and averaged 72137 v/g dw. Diatom valve and diatom specific pigment marker concentrations were not significantly correlated. Peridinin increased after the 1980s in line with intensified use of fertilizer and related increases in nutrient inputs into the marine environment. The increased occurrence of dinoflagellate dominance after the 1980s can be mostly explained by the increase in nutrients. However, the contribution of dinoflagellates to total phytoplankton production (Chl- a) decreased during the final decade of this study, probably because of the overwhelming increase in diatom production that corresponded with the construction of the Three Gorges Dam (TGD) and related light availability. Similarly, the mean ratio of fucoxanthin/peridinin for the period from 1982 to 2001 was 6% less than for 1961 to 1982, while the ratio for 2001 to 2011 was 45.3% greater than for 1982 to 2001. The decadal variation in the fucoxanthin/peridinin ratio implies that dinoflagellate production had been gradually increasing until 2001. We suggest that the observed changes can be explained by anthropogenic impacts, such as nutrient loading and dam construction.
Drew, L.J.; Schuenemeyer, J.H.; Amstrong, T.R.; Sutphin, D.M.
2001-01-01
A model is proposed to explain the statistical relations between the mean initial water well yields from eight time increments from 1984 to 1998 for wells drilled into the crystalline bedrock aquifer system in the Pinardville area of southern New Hampshire and the type of bedrock, mean well depth, and mean well elevation. Statistical analyses show that the mean total yield of drilling increments is positively correlated with mean total well depth and mean well elevation. In addition, the mean total well yield varies with rock type from a minimum of 46.9 L/min (12.4 gpm) in the Damon Pond granite to a maximum of 74.5 L/min (19.7 gpm) in the Permian pegmatite and granite unit. Across the eight drilling increments that comprise 211 wells each, the percentages of very low-yield wells (1.9 L/min [0.5 gpm] or less) and high-yield wells (151.4 L/min [40 gpm] or more) increased, and those of intermediate-yield wells decreased. As housing development progressed during the 1984 to 1998 interval, the mean depth of the wells and their elevations increased, and the mix of percentages of the bedrock types drilled changed markedly. The proposed model uses a feed-forward mechanism to explain the interaction between the increasing mean elevation, mean well depth, and percentages of very low-yielding wells and the mean well yield. The increasing percentages of very low-yielding wells through time and the economics of the housing market may control the system that forces the mean well depths, percentages of high-yield wells, and mean well yields to increase. The reason for the increasing percentages of very low-yield wells is uncertain, but the explanation is believed to involve the complex structural geology and tectonic history of the Pinardville quadrangle.
Mackenbach, Johan P
2014-07-01
Variations in 'culture' are often invoked to explain cross-national variations in health, but formal analyses of this relation are scarce. We studied the relation between three sets of cultural values and a wide range of health behaviours and health outcomes in Europe. Cultural values were measured according to Inglehart׳s two, Hofstede׳s six, and Schwartz׳s seven dimensions. Data on individual and collective health behaviours (30 indicators of fertility-related behaviours, adult lifestyles, use of preventive services, prevention policies, health care policies, and environmental policies) and health outcomes (35 indicators of general health and of specific health problems relating to fertility, adult lifestyles, prevention, health care, and violence) in 42 European countries around the year 2010 were extracted from harmonized international data sources. Multivariate regression analysis was used to relate health behaviours to value orientations, controlling for socioeconomic confounders. In univariate analyses, all scales are related to health behaviours and most scales are related to health outcomes, but in multivariate analyses Inglehart׳s 'self-expression' (versus 'survival') scale has by far the largest number of statistically significant associations. Countries with higher scores on 'self-expression' have better outcomes on 16 out of 30 health behaviours and on 19 out of 35 health indicators, and variations on this scale explain up to 26% of the variance in these outcomes in Europe. In mediation analyses the associations between cultural values and health outcomes are partly explained by differences in health behaviours. Variations in cultural values also appear to account for some of the striking variations in health behaviours between neighbouring countries in Europe (Sweden and Denmark, the Netherlands and Belgium, the Czech Republic and Slovakia, and Estonia and Latvia). This study is the first to provide systematic and coherent empirical evidence that differences between European countries in health behaviours and health outcomes may partly be determined by variations in culture. Paradoxically, a shift away from traditional 'survival' values seems to promote behaviours that increase longevity in high income countries. Copyright © 2014 Elsevier Ltd. All rights reserved.
Weight, gender, and depressive symptoms in South Korea
Han, Seung Yong; SturtzSreetharan, Cindi L.
2017-01-01
Abstract Objectives Obesity consistently predicts depression risk, but the underlying mechanisms are poorly understood. Body concerns are proposed as key. South Korean society is characterized by extremely high levels of explicit weight stigma, possibly the highest globally. Using cross‐sectional Korean 2014 National Health Examination Survey (KNHANES) data, we test this proposition in a nationally representative sample of South Korean adults (N = 5,632). Methods Depressive symptoms (outcome variable), was based on the PHQ‐9. Weight status (predictor variable), was based on direct measures of height and weight converted to BMI. Weight concern was self‐reported. Mediation analyses tested how weight concern mediated the influence of weight status on depressive symptoms for women and men. Results Current weight status influenced depressive symptoms in Korean adults, but not always directly. Concerns of being “fat” mediated that relationship. The effect increased significantly as BMI increased within “normal” and overweight/obese categories for women, and in overweight/obese categories for men. Even though women classified as underweight were significantly more depressed than those in other weight categories, there was no similar mediation effect related to weight concerns. Conclusion For South Koreans, the stress of adhering to social norms and avoiding stigma related to body weight seems to explain the relationship between higher body weight and more depressive symptoms. Women are more vulnerable overall, but men are not immune. This study demonstrates that body concerns help explain why weight predicts depression, and more broadly supports the proposition that widespread weight‐related stigma is a potentially major, if unrecognized, driver of population‐level health disparities. PMID:28161899
Barker, F Keith; Burns, Kevin J; Klicka, John; Lanyon, Scott M; Lovette, Irby J
2013-03-01
Recent analyses suggest that a few major shifts in diversification rate may be enough to explain most of the disparity in diversity among vertebrate lineages. At least one significant increase in diversification rate appears to have occurred within the birds; however, several nested lineages within birds have been identified as hyperdiverse by different studies. A clade containing the finches and relatives (within the avian order Passeriformes), including a large radiation endemic to the New World that comprises ~8% of all bird species, may be the true driver of this rate increase. Understanding the patterns and processes of diversification of this diverse lineage may go a long way toward explaining the apparently rapid diversification rates of both passerines and of birds as a whole. We present the first multilocus phylogenetic analyses of this endemic New World radiation of finch relatives that include sampling of all recognized genera, a relaxed molecular clock analysis of its divergence history, and an analysis of its broad-scale diversification patterns. These analyses recovered 5 major lineages traditionally recognized as avian families, but identified an additional 10 relatively ancient lineages worthy of recognition at the family level. Time-calibrated diversification analyses suggested that at least 3 of the 15 family-level lineages were significantly species poor given the entire group's background diversification rate, whereas at least one-the tanagers of family Thraupidae-appeared significantly more diverse. Lack of an age-diversity relationship within this clade suggests that, due to rapid initial speciation, it may have experienced density-dependent ecological limits on its overall diversity.
Ethnic density of regions and psychiatric disorders among ethnic minority individuals.
Emerson, Scott Daniel; Minh, Anita; Guhn, Martin
2018-03-01
Ethnic minorities form an increasingly large proportion of Canada's population. Living in areas of greater ethnic density may help protect mental health among ethnic minorities through psychosocial pathways such as accessibility to culturally appropriate provision of mental health care, less discrimination and a greater sense of belonging. Mood and anxiety disorders are common psychiatric disorders. This study examined whether ethnic density of regions was related to mood and anxiety disorders among ethnic minorities in Canada. Responses by ethnic minority individuals to the 2011-2014 administrations of the Canadian Community Health Survey ( n = 33,201) were linked to health region ethnic density data. Multilevel logistic regression was employed to model the odds of having mood and/or anxiety disorders associated with increasing region-level ethnic density and to examine whether sense of community belonging helped explain variance in such associations. Analyses were adjusted for individual-level demographic factors as well as region-level socio-economic factors. Higher ethnic density related to lower odds of mood and/or anxiety disorders for Canadian-born (but not foreign-born) ethnic minorities. Sense of community belonging did not help explain such associations, but independently related to lower odds of mood and/or anxiety disorders. These findings remained after adjusting for regional population density and after excluding (rural/remote) regions of very low ethnic density. Ethnic density of regions in Canada may be an important protective factor against mental illness among Canadian-born ethnic minorities. It is important to better understand how, and for which specific ethno-cultural groups, ethnic density may influence mental health.
2010-01-01
Background Bone-destructive disease treatments include bisphosphonates and antibodies against the osteoclast differentiator, RANKL (aRANKL); however, osteonecrosis of the jaw (ONJ) is a frequent side-effect. Current models fail to explain the restriction of bisphosphonate (BP)-related and denosumab (anti-RANKL antibody)-related ONJ to jaws. Msx-1 is exclusively expressed in craniofacial structures and pivotal to cranial neural crest (CNC)-derived periodontal tissue remodeling. We hypothesised that Msx-1 expression might be impaired in bisphosphonate-related ONJ. The study aim was to elucidate Msx-1 and RANKL-associated signal transduction (BMP-2/4, RANKL) in ONJ-altered and healthy periodontal tissue. Methods Twenty ONJ and twenty non-BP exposed periodontal samples were processed for RT-PCR and immunohistochemistry. An automated staining-based alkaline phosphatase-anti-alkaline phosphatase method was used to measure the stained cells:total cell-number ratio (labelling index, Bonferroni adjustment). Real-time RT-PCR was performed on ONJ-affected and healthy jaw periodontal samples (n = 20 each) to quantitatively compare Msx-1, BMP-2, RANKL, and GAPDH mRNA levels. Results Semi-quantitative assessment of the ratio of stained cells showed decreased Msx-1 and RANKL and increased BMP-2/4 (all p < 0.05) expression in ONJ-adjacent periodontal tissue. ONJ tissue also exhibited decreased relative gene expression for Msx-1 (p < 0.03) and RANKL (p < 0.03) and increased BMP-2/4 expression (p < 0.02) compared to control. Conclusions These results explain the sclerotic and osteopetrotic changes of periodontal tissue following BP application and substantiate clinical findings of BP-related impaired remodeling specific to periodontal tissue. RANKL suppression substantiated the clinical finding of impaired bone remodelling in BP- and aRANKL-induced ONJ-affected bone structures. Msx-1 suppression in ONJ-adjacent periodontal tissue suggested a bisphosphonate-related impairment in cellular differentiation that occurred exclusively jaw remodelling. Further research on developmental biology-related unique features of jaw bone structures will help to elucidate pathologies restricted to maxillofacial tissue. PMID:20942943
Wehrhan, Falk; Hyckel, Peter; Ries, Jutta; Stockmann, Phillip; Nkenke, Emeka; Schlegel, Karl A; Neukam, Friedrich W; Amann, Kerstin
2010-10-13
Bone-destructive disease treatments include bisphosphonates and antibodies against the osteoclast differentiator, RANKL (aRANKL); however, osteonecrosis of the jaw (ONJ) is a frequent side-effect. Current models fail to explain the restriction of bisphosphonate (BP)-related and denosumab (anti-RANKL antibody)-related ONJ to jaws. Msx-1 is exclusively expressed in craniofacial structures and pivotal to cranial neural crest (CNC)-derived periodontal tissue remodeling. We hypothesised that Msx-1 expression might be impaired in bisphosphonate-related ONJ. The study aim was to elucidate Msx-1 and RANKL-associated signal transduction (BMP-2/4, RANKL) in ONJ-altered and healthy periodontal tissue. Twenty ONJ and twenty non-BP exposed periodontal samples were processed for RT-PCR and immunohistochemistry. An automated staining-based alkaline phosphatase-anti-alkaline phosphatase method was used to measure the stained cells:total cell-number ratio (labelling index, Bonferroni adjustment). Real-time RT-PCR was performed on ONJ-affected and healthy jaw periodontal samples (n = 20 each) to quantitatively compare Msx-1, BMP-2, RANKL, and GAPDH mRNA levels. Semi-quantitative assessment of the ratio of stained cells showed decreased Msx-1 and RANKL and increased BMP-2/4 (all p < 0.05) expression in ONJ-adjacent periodontal tissue. ONJ tissue also exhibited decreased relative gene expression for Msx-1 (p < 0.03) and RANKL (p < 0.03) and increased BMP-2/4 expression (p < 0.02) compared to control. These results explain the sclerotic and osteopetrotic changes of periodontal tissue following BP application and substantiate clinical findings of BP-related impaired remodeling specific to periodontal tissue. RANKL suppression substantiated the clinical finding of impaired bone remodelling in BP- and aRANKL-induced ONJ-affected bone structures. Msx-1 suppression in ONJ-adjacent periodontal tissue suggested a bisphosphonate-related impairment in cellular differentiation that occurred exclusively jaw remodelling. Further research on developmental biology-related unique features of jaw bone structures will help to elucidate pathologies restricted to maxillofacial tissue.
Cognitive Processes in Alcohol Binges: A Review and Research Agenda
Field, Matt; Schoenmakers, Tim; Wiers, Reinout W.
2010-01-01
Alcohol abuse is associated with a cluster of long-term changes in cognitive processes, as predicted by contemporary models of addiction. In this paper we review evidence which suggests that similar changes may occur during an alcohol binge, and as such they may play an important role in explaining the loss of control over alcohol consumption that occurs during alcohol binges. As a consequence of both acute alcohol intoxication (alcohol ‘priming’ effects) and exposure to environmental alcohol-related cues, we suggest that a number of changes in cognitive processes are likely. These include increased subjective craving for alcohol, increased positive and arousing outcome expectancies and implicit associations for alcohol use, increased attentional bias for alcohol-related cues, increased action tendencies to approach alcohol, increased impulsive decision-making, and impaired inhibitory control over drives and behaviour. Potential reciprocal relationships between these different aspects of cognition during an alcohol binge are discussed. Finally, we discuss the relationship between the current model and existing models of cognitive processes in substance abuse, and we speculate on the implications of the model for the reduction binge drinking and its consequences. PMID:19630725
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hagland, Hanne R.; Nilsson, Linn I.H.; Burri, Lena
Highlights: Black-Right-Pointing-Pointer We investigated mechanisms of mitochondrial regulation in rat hepatocytes. Black-Right-Pointing-Pointer Tetradecylthioacetic acid (TTA) was employed to activate mitochondrial oxidation. Black-Right-Pointing-Pointer Mitochondrial biogenesis and respiration were induced. Black-Right-Pointing-Pointer It was confirmed that PPAR target genes were induced. Black-Right-Pointing-Pointer The mechanism involved activation mTOR. -- Abstract: The hypolipidemic effect of peroxisome proliferator-activated receptor (PPAR) activators has been explained by increasing mitochondrial fatty acid oxidation, as observed in livers of rats treated with the pan-PPAR activator tetradecylthioacetic acid (TTA). PPAR-activation does, however, not fully explain the metabolic adaptations observed in hepatocytes after treatment with TTA. We therefore characterized the mitochondrial effects,more » and linked this to signalling by the metabolic sensor, the mammalian target of rapamycin (mTOR). In hepatocytes isolated from TTA-treated rats, the changes in cellular content and morphology were consistent with hypertrophy. This was associated with induction of multiple mitochondrial biomarkers, including mitochondrial DNA, citrate synthase and mRNAs of mitochondrial proteins. Transcription analysis further confirmed activation of PPAR{alpha}-associated genes, in addition to genes related to mitochondrial biogenesis and function. Analysis of mitochondrial respiration revealed that the capacity of both electron transport and oxidative phosphorylation were increased. These effects coincided with activation of the stress related factor, ERK1/2, and mTOR. The protein level and phosphorylation of the downstream mTOR actors eIF4G and 4E-BP1 were induced. In summary, TTA increases mitochondrial respiration by inducing hypertrophy and mitochondrial biogenesis in rat hepatocytes, via adaptive regulation of PPARs as well as mTOR.« less
Mortality among patients with hypertension from 1995 to 2005: a population-based study
Tu, Karen; Chen, Zhongliang; Lipscombe, Lorraine L.
2008-01-01
Background We have reported that the prevalence of diagnosed hypertension increased by 60% from 1995 to 2005 in Ontario. In the present study, we asked whether this increase is explained by a decrease in the mortality rate. Methods We performed a population-based cohort study using linked administrative data for Ontario, a Canadian province with over 12 million residents. We identified prevalent cases of hypertension using a validated case-definition algorithm for hypertension, and we examined trends in mortality from 1995 to 2005 among adults aged 20 years and older with hypertension. Results The age-and sex-adjusted mortality among patients with hypertension decreased from 11.3 per 1000 people in 1995 to 9.6 per 1000 in 2005 (p < 0.001), which is a relative reduction of 15.5%. We found that the relative decrease in age-adjusted mortality was higher among men than among women (–22.2% v. –7.3%, p < 0.001). Interpretation Mortality rates among patients with hypertension have decreased. Along with an increasing incidence, decreased mortality rates may contribute to the increased prevalence of diagnosed hypertension. Sex-related discrepancies in the reduction of mortality warrant further investigation. PMID:18490639
Mortality among patients with hypertension from 1995 to 2005: a population-based study.
Tu, Karen; Chen, Zhongliang; Lipscombe, Lorraine L
2008-05-20
We have reported that the prevalence of diagnosed hypertension increased by 60% from 1995 to 2005 in Ontario. In the present study, we asked whether this increase is explained by a decrease in the mortality rate. We performed a population-based cohort study using linked administrative data for Ontario, a Canadian province with over 12 million residents. We identified prevalent cases of hypertension using a validated case-definition algorithm for hypertension, and we examined trends in mortality from 1995 to 2005 among adults aged 20 years and older with hypertension. The age- and sex-adjusted mortality among patients with hypertension decreased from 11.3 per 1000 people in 1995 to 9.6 per 1000 in 2005 (p < 0.001), which is a relative reduction of 15.5%. We found that the relative decrease in age-adjusted mortality was higher among men than among women (-22.2% v. -7.3%, p < 0.001). Mortality rates among patients with hypertension have decreased. Along with an increasing incidence, decreased mortality rates may contribute to the increased prevalence of diagnosed hypertension. Sex-related discrepancies in the reduction of mortality warrant further investigation.
A Situation-specific Theory of Midlife Women's Attitudes toward Physical Activity (MAPA)
Im, Eun-Ok; Stuifbergen, Alexa K.; Walker, Lorraine
2010-01-01
This paper presents a situation specific theory—the Midlife Women's Attitudes toward Physical Activity (MAPA) theory—that explains how women's attitudes toward physical activity influence their participation in physical activity. Using the integrative approach of Im, the theory was developed based on the Attitude, Social Influence, and Self Efficacy Model, a review of the related literature, and a study of women's attitudes toward physical activity. As a situation-specific theory, the MAPA theory can be easily linked to nursing practice and research projects related to physical activity in midlife women, especially interventions aimed at increasing midlife women's participation in physical activity. PMID:20113755
Zhang, Hua; Yin, Run-sheng; Feng, Xin-bin; Sommar, Jonas; Anderson, Christopher W N; Sapkota, Atindra; Fu, Xue-wu; Larssen, Thorjørn
2013-11-25
The influence of topography on the biogeochemical cycle of mercury (Hg) has received relatively little attention. Here, we report the measurement of Hg species and their corresponding isotope composition in soil sampled along an elevational gradient transect on Mt. Leigong in subtropical southwestern China. The data are used to explain orography-related effects on the fate and behaviour of Hg species in montane environments. The total- and methyl-Hg concentrations in topsoil samples show a positive correlation with elevation. However, a negative elevation dependence was observed in the mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) signatures of Hg isotopes. Both a MIF (Δ(199)Hg) binary mixing approach and the traditional inert element method indicate that the content of Hg derived from the atmosphere distinctly increases with altitude.
Seniors' prescription drug cost inflation and cost containment: evidence from British Columbia.
Morgan, Steven G; Agnew, Jonathan D; Barer, Morris L
2004-06-01
We develop an analytic framework to map out the nature and relative importance of different cost-driving trends in the prescription drug market. This is used to measure prescription drug cost-drivers for the population of seniors in British Columbia during a period when they received comprehensive public drug coverage. Between 1991 and 2001, expenditures on prescription drugs for BC seniors increased from dollar 149 to 320 million. Increases in the population of seniors, and the rate at which they utilized therapies contributed under half of the total cost increase over the period. Changes in the mix of therapies and the type of product selected explained over half of the observed drug expenditure inflation. Increased generic substitution significantly reduced the price of products selected over the period.
Developmental cascade effects of the New Beginnings Program on adolescent adaptation outcomes.
McClain, Darya Bonds; Wolchik, Sharlene A; Winslow, Emily; Tein, Jenn-Yun; Sandler, Irwin N; Millsap, Roger E
2010-11-01
Using data from a 6-year longitudinal follow-up sample of 240 youth who participated in a randomized experimental trial of a preventive intervention for divorced families with children ages 9-12, the current study tested alternative cascading pathways by which the intervention decreased symptoms of internalizing disorders, symptoms of externalizing disorders, substance use, and risky sexual behavior and increased self-esteem and academic performance in mid- to late adolescence (15-19 years old). It was hypothesized that the impact of the program on adolescent adaptation outcomes would be explained by progressive associations between program-induced changes in parenting and youth adaptation outcomes. The results supported a cascading model of program effects in which the program was related to increased mother-child relationship quality that was related to subsequent decreases in child internalizing problems, which then was related to subsequent increases in self-esteem and decreases in symptoms of internalizing disorders in adolescence. The results were also consistent with a model in which the program increased maternal effective discipline that was related to decreased child externalizing problems, which was related to subsequent decreases in symptoms of externalizing disorders, less substance use, and better academic performance in adolescence. There were no significant differences in the model based on level of baseline risk or adolescent gender. These results provide support for a cascading pathways model of child and adolescent development.
Sarkar, R; Marimuthu, K M
1983-12-01
This study, based on the investigations carried on 82 cases of Turners of which 50 of them were mosaics and 85 cases of Klinefelters of which 70 of them were mosaics, is an attempt to explain the vast range of clinical variations observed in cytogenetically established Turner mosaics (45,X/46,XX) and Klinefelter mosaics (47,XXY/46,XY) in the light of the degree of mosaicism present in them. It was observed that the severity of the syndrome in Turner mosaics and Klinefelter mosaics increased with the relative increase in the abnormal cell line population.
Betrus, P A; Elmore, S K; Woods, N F; Hamilton, P A
1995-01-01
As Western society increases in complexity and becomes more reliant on technology, women who thrive as integrators in interactional modes will face new dilemmas. Many women will view these changes as challenges, but for many other women, who view these changes as threats, the response will be depression. We lay a foundation to an understanding of depression in women, evaluating the current concept of depression and pointing out its limitations. We then review the traditional theories of women's increased vulnerability to depressive disorders, which have failed to explain adequately this phenomenon. A more recent theory of women's depression, based on the self-in-relation theory of women's development, is offered as an alternative.
Tomova, L; Majdandžic, J; Hummer, A; Windischberger, C; Heinrichs, M; Lamm, C
2017-03-01
Recent behavioral investigations suggest that acute stress can increase prosocial behavior. Here, we investigated whether increased empathy represents a potential mechanism for this finding. Using functional magnetic resonance imaging, we assessed the effects of acute stress on neural responses related to automatic and regulatory components of empathy for pain as well as subsequent prosocial behavior. Stress increased activation in brain areas associated with the automatic sharing of others' pain, such as the anterior insula, the anterior midcingulate cortex, and the primary somatosensory cortex. In addition, we found increased prosocial behavior under stress. Furthermore, activation in the anterior midcingulate cortex mediated the effects of stress on prosocial behavior. However, stressed participants also displayed stronger and inappropriate other-related responses in situations which required them to take the perspective of another person, and to regulate their automatic affective responses. Thus, while acute stress may increase prosocial behavior by intensifying the sharing of others' emotions, this comes at the cost of reduced cognitive appraisal abilities. Depending on the contextual constraints, stress may therefore affect empathy in ways that are either beneficial or detrimental. © The Author (2016). Published by Oxford University Press.
Hamasaki, Tomoko; Hagihara, Akihito
2011-04-21
A physician's duty to provide an adequate explanation to the patient is derived from the doctrine of informed consent and the physician's duty of disclosure. However, findings are extremely limited with respect to physicians' specific explanatory behaviours and what might be regarded as a breach of the physicians' duty to explain in an actual medical setting. This study sought to identify physicians' explanatory behaviours that may be related to the physicians' legal liability. We analysed legal decisions of medical malpractice cases between 1990 and 2009 in which the pivotal issue was the physician's duty to explain (366 cases). To identify factors related to the breach of the physician's duty to explain, an analysis was undertaken based on acknowledged breaches with regard to the physician's duty to explain to the patient according to court decisions. Additionally, to identify predictors of physicians' behaviours in breach of the duty to explain, logistic regression analysis was performed. When the physician's explanation was given before treatment or surgery (p = 0.006), when it was relevant or specific (p = 0.000), and when the patient's consent was obtained (p = 0.002), the explanation was less likely to be deemed inadequate or a breach of the physician's duty to explain. Patient factors related to physicians' legally problematic explanations were patient age and gender. One physician factor was related to legally problematic physician explanations, namely the number of physicians involved in the patient's treatment. These findings may be useful in improving physician-patient communication in the medical setting.
2011-01-01
Background A physician's duty to provide an adequate explanation to the patient is derived from the doctrine of informed consent and the physician's duty of disclosure. However, findings are extremely limited with respect to physicians' specific explanatory behaviours and what might be regarded as a breach of the physicians' duty to explain in an actual medical setting. This study sought to identify physicians' explanatory behaviours that may be related to the physicians' legal liability. Methods We analysed legal decisions of medical malpractice cases between 1990 and 2009 in which the pivotal issue was the physician's duty to explain (366 cases). To identify factors related to the breach of the physician's duty to explain, an analysis was undertaken based on acknowledged breaches with regard to the physician's duty to explain to the patient according to court decisions. Additionally, to identify predictors of physicians' behaviours in breach of the duty to explain, logistic regression analysis was performed. Results When the physician's explanation was given before treatment or surgery (p = 0.006), when it was relevant or specific (p = 0.000), and when the patient's consent was obtained (p = 0.002), the explanation was less likely to be deemed inadequate or a breach of the physician's duty to explain. Patient factors related to physicians' legally problematic explanations were patient age and gender. One physician factor was related to legally problematic physician explanations, namely the number of physicians involved in the patient's treatment. Conclusion These findings may be useful in improving physician-patient communication in the medical setting. PMID:21510891
Martínez-Andújar, Cristina; Ruiz-Lozano, Juan M; Dodd, Ian C; Albacete, Alfonso; Pérez-Alfocea, Francisco
2017-01-01
Grafting provides a tool aimed to increase low-P stress tolerance of crops, however, little is known about the mechanism (s) by which rootstocks can confer resistance to P deprivation. In this study, 4 contrasting groups of rootstocks from different genetic backgrounds ( Solanum lycopersicum var. cerasiforme and introgression and recombinant inbred lines derived from the wild relatives S. pennellii and S. pimpinellifolium ) were grafted to a commercial F1 hybrid scion and cultivated under control (1 mM, c ) and P deficient (0.1 mM, p ) conditions for 30 days, to analyze rootstocks-mediated traits that impart low ( L , low shoot dry weight, SDW) or high ( H , high SDW) vigor. Xylem sap ionic and hormonal anlyses leaf nutritional status suggested that some physiological traits can explain rootstocks impacts on shoot growth. Although xylem P concentration increased with root biomass under both growing conditions, shoot biomass under low-P was explained by neither changes in root growth nor P transport and assimilation. Indeed, decreased root P export only explained the sensitivity of the HcLp rootstocks, while leaf P status was similarly affected in all graft combinations. Interestingly, most of the nutrients analyzed in the xylem sap correlated with root biomass under standard fertilization but only Ca was consistently related to shoot biomass under both control and low-P, suggesting an important role for this nutrient in rootstock-mediated vigor. Moreover, foliar Ca, S, and Mn concentrations were (i) specifically correlated with shoot growth under low-P and (ii) positively and negatively associated to the root-to-shoot transport of the cytokinin trans -zeatin ( t -Z) and the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), respectively. Indeed, those hormones seem to play an antagonistic positive ( t -Z) and negative (ACC) role in the rootstock-mediated regulation of shoot growth in response to P nutrition. The use of Hp -type rootstocks seems to enhance P use efficiency of a commercial scion variety, therefore could potentially be used for increasing yield and agronomic stability under low P availability.
NASA Astrophysics Data System (ADS)
Rodríguez, G.; Arango, M. I.; Zapata, G.; Bermúdez, J. G.
2018-01-01
Field, petrographic, and geochemical characterization along with U-Pb zircon geochronology of the Jurassic plutons exposed in the Upper Magdalena Valley (Colombia) allowed recognizing distinct western and eastern suites formed in at least three magmatic pulses. The western plutons crop out between the eastern flank of the Central Cordillera and the Las Minas range, being limited by the Avirama and the Betania-El Agrado faults. The western suite comprises a quartz monzonite - quartz monzodiorite - quartz diorite series and subordinate monzogranites. Chemically, the rocks are high-K calc-alkaline I-type granitoids (some reaching the shoshonitic series) with metaluminous of magnesium affinity. Trace-element tectonic discrimination is consistent with magmatism in a continental arc environment. Most rocks of this suite crystallized between 195 and 186 Ma (Early Jurassic, Pliensbachian), but locally some plutons yielded younger ages between 182 and 179 Ma (Early Jurassic, Toarcian). The eastern suite crops out in the eastern margin of the Upper Magdalena Valley, east of the Betania - El Agrado fault. Plutons of this unit belong to the monzogranite series with rock types ranging between syenogranites and granodiorites. They are high-K calc-alkaline continental granitoids, some metaluminous and some peraluminous, related to I-type granites generated in a volcanic arc. Crystallization of the suite was between 173 and 169 Ma (Middle Jurassic, Aalenian-Bajocian), but locally these rocks contain zircon with earlier inherited ages related to the magmatic pulse of the western suite between 182 and 179 Ma (Early Jurassic, Toarcian). The evolution of the Jurassic plutons in the Upper Magdalena Valley is best explained by onset or increase in subduction erosion of the accretionary prism. This explains the eastward migration of the arc away from the trench. Subduction of prism sediments increased the water flux from the subducting slab, decreasing solidus temperatures, therefore increasing the volume of magma and the amount of crustal melts involved in the magma. This is explains the crystallization of older and more primitive quartz-monzodiorite stocks in the west and the later crystallization of granitic bodies with batholitic dimensions in the east.
Decomposition of the drivers of the U.S. hospital spending growth, 2001–2009
2014-01-01
Background United States health care spending rose rapidly in the 2000s, after a period of temporary slowdown in the 1990s. However, the description of the overall trend and the understanding of the underlying drivers of this trend are very limited. This study investigates how well historical hospital cost/revenue drivers explain the recent hospital spending trend in the 2000s, and how important each of these drivers is. Methods We used aggregated time series data to describe the trend in total hospital spending, price, and quantity between 2001 and 2009. We used the Oaxaca-Blinder method to investigate the relative importance of major hospital cost/spending drivers (derived from the literature) in explaining the change in hospital spending patterns between 2001 and 2007. We assembled data from Medicare Cost Reports, American Hospital Association annual surveys, Prospective Payment System (PPS) Impact Files, Medicare Provider Analysis and Review (MedPAR) Medicare claims data, InterStudy reports, National Health Expenditure data, and Area Resource Files. Results Aggregated time series trends show that high hospital spending between 2001 and 2009 appears to be driven by higher payment per unit of hospital output, not by increased utilization. Results using the Oaxaca-Blinder regression decomposition method indicate that changes in historically important spending drivers explain a limited 30% of unit-payment growth, but a higher 60% of utilization growth. Hospital staffing and labor-related costs, casemix, and demographics are the most important drivers of higher hospital revenue, utilization, and unit-payment. Technology is associated with lower utilization, higher unit payment, and limited increases in total revenue. Market competition, primarily because of increased managed care concentration, moderates total revenue growth by driving lower unit payment. Conclusions Much of the rapidly rising hospital spending growth in the 2000s in the United States is driven by factors not commonly known or well measured. Future studies need to explore new factors and dynamics that drive longer-term hospital spending growth in recent years, particularly through the channel of higher prices. PMID:24886580
Özhayat, Esben B
2013-10-01
To meaningfully interpret oral health-related quality of life (OHRQoL) measures, the influence of personality traits must be investigated. To investigate and quantify the influence of self-esteem and negative affectivity (NA) on OHRQoL. It was hypothesized that low self-esteem and high NA would be associated with worse OHRQoL. OHRQoL measured by the Oral Health Impact Profile 49 (OHIP-49), self-esteem measured by the Rosenberg Self-Esteem Scale (RSES), NA measured by the Eysenck Personality Inventory Questionnaire (EPI-Q), global oral rating of oral comfort and controlling variables (gender, age, number of teeth, experience of wearing removable dental prostheses (RDP), location of missing teeth and zone of missing teeth) were collected from 81 patients with partial tooth loss, signed in for treatment with RDP. Bivariate analyses showed that the EPI-Q score had the highest correlation with OHIP-49 score (R = 0.5). Both EPI-Q and RSES score had a stronger correlation with psychosocial items than physical/functional items of the OHIP-49. In the multivariate analyses, the controlling variables alone explained 17.75% of the variance in OHIP-49 score, while addition of EPI-Q score, RSES score and both EPI-Q and RSES score explained additionally 11.64%, 6.07% and 14.12%, respectively. For each unit increase in EPI-Q score, the OHIP-49 score increased 5.1 units and for each unit increase in RSES score, the OHIP-49 score decreased 1.1. NA was statistically and clinically significantly higher and self-esteem was statistically significantly lower in patients reporting worse oral comfort. NA had the strongest and most clinically meaningful influence, but both NA and self-esteem was found to influence OHRQoL; low self-esteem and high NA was associated with worse OHRQoL. This indicates the possibility to explain some of the impact of tooth loss on OHRQoL based on personality traits. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
De Boer, Dolf; Delnoij, Diana; Rademakers, Jany
2010-01-01
Abstract Background Patient‐given global ratings are frequently interpreted as summary measures of the patient perspective, with limited understanding of what these ratings summarize. Global ratings may be determined by patient experiences on priority aspects of care. Objectives (i) identify patient priorities regarding elements of care for breast cancer, hip‐ or knee surgery, cataract surgery, rheumatoid arthritis and diabetes, (ii) establish whether experiences regarding priorities are associated with patient‐given global ratings, and (iii) determine whether patient experiences regarding priorities are better predictors of global ratings than experiences concerning less important aspects of care. Setting and participants Data collected for the development of five consumer quality index surveys – disease‐specific questionnaires that capture patient experiences and priorities – were used. Results Priorities varied: breast cancer patients for example, prioritized rapid access to care and diagnostics, while diabetics favoured dignity and appropriate frequency of tests. Experiences regarding priorities were inconsistently related to global ratings of care. Regression analyses indicated that demographics explain 2.4–8.4% of the variance in global rating. Introducing patient experiences regarding priorities increased the variance explained to 21.1–35.1%; models with less important aspects of care explained 11.8–23.2%. Conclusions Some experiences regarding priorities are strongly related to the global rating while others are poorly related. Global ratings are marginally dependent on demographics, and experiences regarding priorities are somewhat better predictors of global rating than experiences regarding less important elements. As it remains to be fully determined what global ratings summarize, caution is warranted when using these ratings as summary measures. PMID:20550597
NASA Astrophysics Data System (ADS)
Chouchane, Hatem; Krol, Maarten; Hoekstra, Arjen
2016-04-01
Water scarcity is among the main problems faced by many societies. Growing water demands put increasing pressure on local water resources, especially in water-short countries. Virtual water trade can play a key role in filling the gap between local demands and supply. This study aims to analyze the changes in virtual water trade of Tunisia in relation to environmental and socio-economic factors such as GDP, irrigated land, precipitation, population and water scarcity. The water footprint is estimated using Aquacrop for six crops over the period 1981-2010 at daily basis and a spatial resolution of 5 by 5 arc minutes. Virtual water trade is quantified at yearly basis. Regression models are used to investigate changes in virtual water trade in relation to various environmental and socio-economic factors. The explaining variables are selected in order to help understanding the trend and the inter-annual variability of the net virtual water import; GDP, population and irrigated land are hypothesized to explain the trend, and precipitation and water scarcity to explain variability. The selected crops are divided into three baskets. The first basket includes the two most imported crops, which are mainly rain-fed (wheat and barley). The second basket contains the two most exported crops, which are both irrigated and rain-fed (olives and dates). In the last basket we find the two highest economic blue water productive crops, which are mainly irrigated (tomatoes and potatoes). The results show the impact of each factor on net virtual water import of the selected crops during the period 1981-2010. Keywords: Virtual water, trade patterns, Aquacrop, Tunisia, water scarcity, water footprint.
The drawing effect: Evidence for reliable and robust memory benefits in free recall.
Wammes, Jeffrey D; Meade, Melissa E; Fernandes, Myra A
2016-01-01
In 7 free-recall experiments, the benefit of creating drawings of to-be-remembered information relative to writing was examined as a mnemonic strategy. In Experiments 1 and 2, participants were presented with a list of words and were asked to either draw or write out each. Drawn words were better recalled than written. Experiments 3-5 showed that the memory boost provided by drawing could not be explained by elaborative encoding (deep level of processing, LoP), visual imagery, or picture superiority, respectively. In Experiment 6, we explored potential limitations of the drawing effect, by reducing encoding time and increasing list length. Drawing, relative to writing, still benefited memory despite these constraints. In Experiment 7, the drawing effect was significant even when encoding trial types were compared in pure lists between participants, inconsistent with a distinctiveness account. Together these experiments indicate that drawing enhances memory relative to writing, across settings, instructions, and alternate encoding strategies, both within- and between-participants, and that a deep LoP, visual imagery, or picture superiority, alone or collectively, are not sufficient to explain the observed effect. We propose that drawing improves memory by encouraging a seamless integration of semantic, visual, and motor aspects of a memory trace.
Inter-annual Variability of Snowfall in the Lower Peninsula of Michigan, USA
NASA Astrophysics Data System (ADS)
Meng, L.
2016-12-01
Winter snowfall, particularly lake-effect snowfall, impacts all aspects of Michigan life in the wintertime, from motorsports and tourism to impacting the day-to-day lives of residents. Understanding the inter-annual variability of winter snowfall will provide sound basis for local community safety management and improve weather forecasting. This study attempts to understand the trend in winter snowfall and the influencing factors of winter snowfall variability in the Lower Peninsula of Michigan (LPM) using station snowfall measurements and statistical analysis. Our study demonstrates that snowfall has significantly increased from 1932 to 2015. Correlation analysis suggests that regionally average air temperatures have a strong negative relationship with snowfall in LPM. On average, approximately 27% of inter-annual variability in snowfall can be explained by regionally average air temperatures. ENSO events are also negatively related to snowfall in LPM and can explain 8% of inter-annual variability. North Atlantic Oscillation (NAO) does not have strong influence on snowfall. Composite analysis demonstrates that on annual basis, more winter snowfall occurs during the years with higher maximum ice cover (MIC) than during the years with lower MIC in Lake Michigan. Higher MIC is often associated with lower air temperatures which are negatively related to winter snowfall. This study could provide insight on future snow related climate model improvement and weather forecasting.
Oishi, Shigehiro; Kesebir, Selin
2015-10-01
One of the most puzzling social science findings in the past half century is the Easterlin paradox: Economic growth within a country does not always translate into an increase in happiness. We provide evidence that this paradox can be partly explained by income inequality. In two different data sets covering 34 countries, economic growth was not associated with increases in happiness when it was accompanied by growing income inequality. Earlier instances of the Easterlin paradox (i.e., economic growth not being associated with increasing happiness) can thus be explained by the frequent concurrence of economic growth and growing income inequality. These findings suggest that a more even distribution of growth in national wealth may be a precondition for raising nationwide happiness. © The Author(s) 2015.
A Particle Model Explaining Mass and Relativity in a Physical Way
NASA Astrophysics Data System (ADS)
Giese, Albrecht
Physicists' understanding of relativity and the way it is handled is up to present days dominated by the interpretation of Albert Einstein, who related relativity to specific properties of space and time. The principal alternative to Einstein's interpretation is based on a concept proposed by Hendrik A. Lorentz, which uses knowledge of classical physics alone to explain relativistic phenomena. In this paper, we will show that on the one hand the Lorentz-based interpretation provides a simpler mathematical way of arriving at the known results for both Special and General Relativity. On the other hand, it is able to solve problems which have remained open to this day. Furthermore, a particle model will be presented, based on Lorentzian relativity and the quantum mechanical concept of Louis de Broglie, which explains the origin of mass without the use of the Higgs mechanism. It is based on the finiteness of the speed of light and provides classical results for particle properties which are currently only accessible through quantum mechanics.
Pan, Z H; Segal, M M; Lipton, S A
1996-12-24
Nitric oxide (NO.) does not react significantly with thiol groups under physiological conditions, whereas a variety of endogenous NO donor molecules facilitate rapid transfer to thiol of nitrosonium ion (NO+, with one less electron than NO.). Here, nitrosonium donors are shown to decrease the efficacy of evoked neurotransmission while increasing the frequency of spontaneous miniature excitatory postsynaptic currents (mEPSCs). In contrast, pure NO donors have little effect (displaying at most only a slight increase) on the amplitude of evoked EPSCs and frequency of spontaneous mEPSCs in our preparations. These findings may help explain heretofore paradoxical observations that the NO moiety can either increase, decrease, or have no net effect on synaptic activity in various preparations.
Cosmic radiation and cancer: is there a link?
Di Trolio, Rossella; Di Lorenzo, Giuseppe; Fumo, Bruno; Ascierto, Paolo A
2015-01-01
Cosmic radiation can cause genetic and cytogenetic damage. Certain occupations including airline pilots and cabin crew are acknowledged to have a greater exposure to cosmic radiation. In a systematic search of MEDLINE, performed from 1990 to 2014, we analyzed clinical studies using the keywords: cosmic radiation, cancer, chromosome aberration, pilots and astronauts. Increased incidence of skin cancers among airline cabin crew has been reported in a number of studies and appears to be the most consistent finding. However, as with other cancers, it is unclear whether increased exposure to cosmic radiation is a factor in the increased incidence or whether this can be explained by lifestyle factors. Further research is needed to clarify the risk of cancer in relation to cosmic radiation.
Steers, Mai-Ly N.; Neighbors, Clayton; Christina Hove, M.; Olson, Nichole; Lee, Christine M.
2015-01-01
Objective: Although the concepts of harmonious and obsessive passion have been productive in explaining why people eagerly engage in such activities as sports, Internet use, and gambling, previous research has not yet extended these models to explain alcohol and marijuana use among college students. The current research was conducted to clarify the relationships among harmonious and obsessive passion, alcohol and marijuana use, and negative consequences. Method: Two studies were conducted using online assessments. In Study 1, 748 heavy drinking college students (58% female) were recruited and completed measures of passion for drinking alcohol, alcohol use, and alcohol-related negative consequences. In Study 2, 352 regular marijuana-using students (54% female) were recruited and completed assessments of marijuana passion, marijuana use, and marijuana-related consequences. Results: Study 1 found that among heavy drinking college students, harmonious passion was a stronger predictor of increased consumption than was obsessive passion, whereas obsessive passion was a stronger predictor of alcohol-related problems than was harmonious passion. Study 2 revealed similar findings with regard to harmonious passion predicting marijuana consumption; however, unlike Study 1, no significant difference between the passions was found in predicting marijuana-related problems. Conclusions: This research provides a novel perspective on motivation for alcohol and marijuana use. Findings suggest that understanding the locus of young adults’ passion for substance use may be helpful in identifying those who are likely to develop a substance use disorder and therefore may be the most in need of assistance and intervention. PMID:26402355
Steers, Mai-Ly N; Neighbors, Clayton; Hove, M Christina; Olson, Nichole; Lee, Christine M
2015-09-01
Although the concepts of harmonious and obsessive passion have been productive in explaining why people eagerly engage in such activities as sports, Internet use, and gambling, previous research has not yet extended these models to explain alcohol and marijuana use among college students. The current research was conducted to clarify the relationships among harmonious and obsessive passion, alcohol and marijuana use, and negative consequences. Two studies were conducted using online assessments. In Study 1, 748 heavy drinking college students (58% female) were recruited and completed measures of passion for drinking alcohol, alcohol use, and alcohol-related negative consequences. In Study 2, 352 regular marijuana-using students (54% female) were recruited and completed assessments of marijuana passion, marijuana use, and marijuana-related consequences. Study 1 found that among heavy drinking college students, harmonious passion was a stronger predictor of increased consumption than was obsessive passion, whereas obsessive passion was a stronger predictor of alcohol-related problems than was harmonious passion. Study 2 revealed similar findings with regard to harmonious passion predicting marijuana consumption; however, unlike Study 1, no significant difference between the passions was found in predicting marijuana-related problems. This research provides a novel perspective on motivation for alcohol and marijuana use. Findings suggest that understanding the locus of young adults' passion for substance use may be helpful in identifying those who are likely to develop a substance use disorder and therefore may be the most in need of assistance and intervention.
Vieira, Verónica M; Fabian, M Patricia; Webster, Thomas F; Levy, Jonathan I; Korrick, Susan A
2017-05-15
Attention-deficit/hyperactivity disorder (ADHD) has an uncertain etiology, with potential contributions from different risk factors such as prenatal environmental exposure to organochlorines and metals, social risk factors, and genetics. The degree to which geographic variability in ADHD is independent of, or explained by, risk factors may provide etiological insight. We investigated determinants of geographic variation in ADHD-related behaviors among children living near the polychlorinated biphenyl-contaminated New Bedford Harbor (NBH) Superfund site in Massachusetts. Participants were 573 children recruited at birth (1993-1998) who were born to mothers residing near the NBH site. We assessed ADHD-related behaviors at age 8 years using Conners' Teacher Rating Scale-Revised: Long Version. Adjusted generalized additive models were used to smooth the association of pregnancy residence with ADHD-related behaviors and assess whether prenatal organochlorine or metal exposures, sociodemographic factors, or other factors explained spatial patterns. Models that adjusted for child's age and sex displayed significantly increased ADHD-related behavior among children whose mothers resided west of the NBH site during pregnancy. These spatial patterns persisted after adjusting for prenatal exposure to organochlorines and metals but were no longer significant after controlling for sociodemographic factors. The findings underscore the value of spatial analysis in identifying high-risk subpopulations and evaluating candidate risk factors. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.
Theory of mind and Darwin's legacy.
Searle, John
2013-06-18
We do not have an adequate theory of consciousness. Both dualism and materialism are mistaken because they deny consciousness is part of the physical world. False claims include (i) behaviorism, (ii) computationalism, (iii) epiphenomenalism, (iv) the readiness potential, (v) subjectivity, and (vi) materialism. Ontological subjectivity does not preclude epistemic objectivity. Observer relative phenomena are created by consciousness, but consciousness is not itself observer relative. Consciousness consists of feeling, sentience, or awareness with (i) qualitativeness, (ii) ontological subjectivity, (iii) unified conscious field, (iv) intentionality, and (v) intentional causation. All conscious states are caused by lower level neurobiological processes in the brain, and they are realized in the brain as higher level features. Efforts to get a detailed scientific account of how brain processes cause consciousness are disappointing. The Darwinian revolution gave us a new form of explanation; two levels were substituted: a causal level, where we specify the mechanism by which the phenotype functions, and a functional level, where we specify the selectional advantage that the phenotype provides. Sociobiology attempted to explain general features of human society, ethics, etc. It failed. For the incest taboo, it confuses inhibition with prohibition. It did not explain the moral force of the taboo. To explain the function of consciousness we cannot ask, "What would be subtracted if we subtracted consciousness but left everything else the same?" We cannot leave everything else the same because consciousness is necessary for higher functions of human and animal life. The unified conscious field gives the organism vastly increased power.
Theory of mind and Darwin’s legacy
Searle, John
2013-01-01
We do not have an adequate theory of consciousness. Both dualism and materialism are mistaken because they deny consciousness is part of the physical world. False claims include (i) behaviorism, (ii) computationalism, (iii) epiphenomenalism, (iv) the readiness potential, (v) subjectivity, and (vi) materialism. Ontological subjectivity does not preclude epistemic objectivity. Observer relative phenomena are created by consciousness, but consciousness is not itself observer relative. Consciousness consists of feeling, sentience, or awareness with (i) qualitativeness, (ii) ontological subjectivity, (iii) unified conscious field, (iv) intentionality, and (v) intentional causation. All conscious states are caused by lower level neurobiological processes in the brain, and they are realized in the brain as higher level features. Efforts to get a detailed scientific account of how brain processes cause consciousness are disappointing. The Darwinian revolution gave us a new form of explanation; two levels were substituted: a causal level, where we specify the mechanism by which the phenotype functions, and a functional level, where we specify the selectional advantage that the phenotype provides. Sociobiology attempted to explain general features of human society, ethics, etc. It failed. For the incest taboo, it confuses inhibition with prohibition. It did not explain the moral force of the taboo. To explain the function of consciousness we cannot ask, “What would be subtracted if we subtracted consciousness but left everything else the same?” We cannot leave everything else the same because consciousness is necessary for higher functions of human and animal life. The unified conscious field gives the organism vastly increased power. PMID:23754416
Esmaeilzadeh, Safooreh; Allahverdipour, Hamid; Fathi, Behrouz; Shirzadi, Shayesteh
2016-01-01
Background: In spite of developed countries there are progressive trend about HIV/AIDS and its’ aspects of transmission in the low socio-economic societies. The aim of this was to explain the youth's behavior in adopting HIV/AIDS related preventive behaviors in a sample of Iranian university students by emphasizing on fear appeals approaches alongside examining the role of self-control trait for explaining adoption on danger or fear control processes based on Extended Parallel Process Model (EPPM). Methods: A sample of 156 randomly selected university students in Jolfa, Iran was recruited in a predictive cross-sectional study by application of a researcher-designed questionnaire through self-report data collection manner. Sexual high risk behaviors, the EPPM variables, self-control trait, and general self-efficacy were measured as theoretical framework. Results: Findings indicated that 31.3% of participants were in the fear control process versus 68.7% in danger control about HIV/AIDS and also the presence of multi-sex partners and amphetamine consumption amongst the participants. Low self-control trait and low perceived susceptibility significantly were related to having a history of multi-sex partners while high level of self-efficacy significantly increased the probability of condom use. Conclusion: Findings of the study were indicative of the protective role of high level of self-control, perceived susceptibility and self-efficacy factors on youth's high-risk behaviors and their preventative skills as well. PMID:26573026
Mechanisms of nutrient retention and its relation to flow connectivity in river-floodplain corridors
Larsen, Laurel; Harvey, Judson; Maglio, Morgan M.
2015-01-01
Understanding heterogeneity or patchiness in the distribution of vegetation and retention of C and nutrients in river corridors is critical for setting priorities for river management and restoration. Several mechanisms of spatial differentiation in nutrient retention in river and floodplain corridors have been recognized, but few studies have distinguished their relative importance or established their role in long-term geomorphic change, nutrient retention, and connectivity with downstream systems. We evaluated the ability of 3 mechanisms (evapotranspiration focusing [EF], differential hydrologic exchange [DHE], and particulate nutrient redistribution [PNR]) to explain spatial patterns of P retention and function in the Everglades (Florida, USA). We used field measurements in sloughs and on slightly higher, more densely vegetated ridges to quantify P fluxes attributable to the 3 mechanisms. EF does not explain Everglades nutrient retention or P concentrations on ridges and in sloughs. However, DHE resulting from different periods of groundwater–surface-water connectivity across topographic elements is the primary cause of elevated P concentrations on ridges and completely explains interpatch differences in long-term P accumulation rates. With historical flow velocities, which were an order of magnitude higher than at present, PNR would have further increased the interpatch difference in long-term P retention rates nearly 2-fold. In conclusion, DHE and PNR are the dominant drivers of nutrient patchiness in the Everglades and are hypothesized to be important in P-limited river and floodplain corridors globally.
NASA Astrophysics Data System (ADS)
Seo, Jeong Hyun; Jeong, Heui Seob; Lee, Joo Yul; Yoon, Cha Keun; Kim, Joong Kyun; Whang, Ki-Woong
2000-08-01
We measured the time integrated vacuum ultraviolet (VUV) emission spectra of He-Ne-Xe gas mixture from a surface type alternating current (ac) plasma display panel cell. The measured emission lines are the resonance line (147 nm) from Xe*(1s4), the first continuum (150 nm) and the second continuum (173 nm) from Xe dimer excited states. The relative intensities of VUV spectral lines from Xe* and Xe2* are dependent on the He/Ne mixing ratio as well as the Xe partial and total pressure. The intensity of 147 nm VUV increases with the Ne content increase and Xe2* molecular emission increases with the He content increase. Infrared (IR) spectra and the time variation of VUV were measured to explain the reaction pathway and the effect of the mixing ratio of He/Ne on the spectral intensity. A detailed study for the decay time shows that the decay time of 147 nm has two time constants and the radiation of 150 and 173 nm results mainly from Xe*(1s5). The IR spectra shows that the contribution from Xe**(>6 s) to Xe*(1s5) and Xe*(1s4) in He-Xe is different from that of Ne-Xe. The change of IR intensity explains the spectral intensity variations of He-Xe and Ne-Xe discharge.
Why are some STEM fields more gender balanced than others?
Cheryan, Sapna; Ziegler, Sianna A; Montoya, Amanda K; Jiang, Lily
2017-01-01
Women obtain more than half of U.S. undergraduate degrees in biology, chemistry, and mathematics, yet they earn less than 20% of computer science, engineering, and physics undergraduate degrees (National Science Foundation, 2014a). Gender differences in interest in computer science, engineering, and physics appear even before college. Why are women represented in some science, technology, engineering, and mathematics (STEM) fields more than others? We conduct a critical review of the most commonly cited factors explaining gender disparities in STEM participation and investigate whether these factors explain differential gender participation across STEM fields. Math performance and discrimination influence who enters STEM, but there is little evidence to date that these factors explain why women's underrepresentation is relatively worse in some STEM fields. We introduce a model with three overarching factors to explain the larger gender gaps in participation in computer science, engineering, and physics than in biology, chemistry, and mathematics: (a) masculine cultures that signal a lower sense of belonging to women than men, (b) a lack of sufficient early experience with computer science, engineering, and physics, and (c) gender gaps in self-efficacy. Efforts to increase women's participation in computer science, engineering, and physics may benefit from changing masculine cultures and providing students with early experiences that signal equally to both girls and boys that they belong and can succeed in these fields. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Bay, Christiane; Kejs, Anne Mette Tranberg; Storm, Hans H; Engholm, Gerda
2015-02-01
The incidence of melanoma of the skin has risen in Denmark in recent decades, the increase being steeper from 2004. It is unclear whether this represents a true rise in incidence or whether it is caused by an increased awareness of the condition. To assess whether the increase was characterised by early-stage melanomas and a higher proportion of melanomas with superficial spreading morphology, we studied all skin melanoma patients registered in the Danish Cancer Register 1989-2011 (n=27,010) and followed up for death through 2013. Trends in age-standardised incidence by sex, subsite and morphology, relative survival, TNM stage distribution and stage-specific relative survival from 2004 were analysed. The incidence of melanoma more than doubled over 23 years. A steeper increase from 2004 was driven mainly by superficial spreading tumours, but the proportion of nodular melanomas in patients 50 years of age and over also increased significantly. The largest increase occurred for stage I tumours and for tumours on the trunk. From 1989-1993 to 2009-2011 the 5-year relative survival increased at 12% and 6% points for male and female patients, respectively. Greater awareness, and thus lower stage at diagnosis (mediated by a large skin cancer prevention campaign from 2007), might explain part of the increase, but the increase in nodular melanoma also points to a genuine increase in the risk of melanoma. Copyright © 2014 Elsevier Ltd. All rights reserved.
Gorski, Jeff P.; Huffman, Nichole T.; Vallejo, Julian; Brotto, Leticia; Chittur, Sridar V.; Breggia, Anne; Stern, Amber; Huang, Jian; Mo, Chenglin; Seidah, Nabil G.; Bonewald, Lynda; Brotto, Marco
2016-01-01
Conditional deletion of Mbtps1 (cKO) protease in bone osteocytes leads to an age-related increase in mass (12%) and in contractile force (30%) in adult slow twitch soleus muscles (SOL) with no effect on fast twitch extensor digitorum longus muscles. Surprisingly, bone from 10–12-month-old cKO animals was indistinguishable from controls in size, density, and morphology except for a 25% increase in stiffness. cKO SOL exhibited increased expression of Pax7, Myog, Myod1, Notch, and Myh3 and 6-fold more centralized nuclei, characteristics of postnatal regenerating muscle, but only in type I myosin heavy chain-expressing cells. Increased expression of gene pathways mediating EGF receptor signaling, circadian exercise, striated muscle contraction, and lipid and carbohydrate oxidative metabolism were also observed in cKO SOL. This muscle phenotype was not observed in 3-month-old mice. Although Mbtps1 mRNA and protein expression was reduced in cKO bone osteocytes, no differences in Mbtps1 or cre recombinase expression were observed in cKO SOL, explaining this age-related phenotype. Understanding bone-muscle cross-talk may provide a fresh and novel approach to prevention and treatment of age-related muscle loss. PMID:26719336
Climate-driven changes in grassland vegetation, snow cover, and lake water of the Qinghai Lake basin
NASA Astrophysics Data System (ADS)
Wang, Xuelu; Liang, Tiangang; Xie, Hongjie; Huang, Xiaodong; Lin, Huilong
2016-07-01
Qinghai Lake basin and the lake have undergone significant changes in recent decades. We examine MODIS-derived grassland vegetation and snow cover of the Qinghai Lake basin and their relations with climate parameters during 2001 to 2010. Results show: (1) temperature and precipitation of the Qinghai Lake basin increased while evaporation decreased; (2) most of the grassland areas improved due to increased temperature and growing season precipitation; (3) weak relations between snow cover and precipitation/vegetation; (4) a significantly negative correlation between lake area and temperature (r=-0.9, p<0.05) and (5) a positive relation between lake level (lake-level difference) and temperature (precipitation). Compared with Namco Lake (located in the inner Tibetan Plateau) where the primary water source of lake level increases was the accelerated melt of glacier/perennial snow cover in the lake basin, for the Qinghai Lake, however, it was the increased precipitation. Increased precipitation explained the improvement of vegetation cover in the Qinghai Lake basin, while accelerated melt of glacier/perennial snow cover was responsible for the degradation of vegetation cover in Namco Lake basin. These results suggest different responses to the similar warming climate: improved (degraded) ecological condition and productive capacity of the Qinghai Lake basin (Namco Lake basin).
Ohsumi, Akihiro; Hamasaki, Akihiro; Nakagawa, Hiroshi; Yoshida, Hiroe; Shiraiwa, Tatsuhiko; Horie, Takeshi
2007-02-01
Identification of physiological traits associated with leaf photosynthetic rate (Pn) is important for improving potential productivity of rice (Oryza sativa). The objectives of this study were to develop a model which can explain genotypic variation and ontogenetic change of Pn in rice under optimal conditions as a function of leaf nitrogen content per unit area (N) and stomatal conductance (g(s)), and to quantify the effects of interaction between N and g(s) on the variation of Pn. Pn, N and g(s) were measured at different developmental stages for the topmost fully expanded leaves in ten rice genotypes with diverse backgrounds grown in pots (2002) and in the field (2001 and 2002). A model of Pn that accounts for carboxylation and CO diffusion processes, and assumes that the ratio of internal conductance to g(s) is constant, was constructed, and its goodness of fit was examined. Considerable genotypic differences in Pn were evident for rice throughout development in both the pot and field experiments. The genotypic variation of Pn was correlated with that of g(s) at a given stage, and the change of Pn with plant development was closely related to the change of N. The variation of g(s) among genotypes was independent of that of N. The model explained well the variation in Pn of the ten genotypes grown under different conditions at different developmental stages. Conclusions The response of Pn to increased N differs with g(s), and the increase in Pn of genotypes with low g(s) is smaller than that of genotypes with high g(s). Therefore, simultaneous improvements of these two traits are essential for an effective breeding of rice genotypes with increased Pn.
Kelly, John F; Greene, M Claire
2013-12-01
Empirical support for the recovery utility of 12-step mutual-help organizations (MHOs) has led to increased investigation of how such organizations confer benefit. The Twelve Promises of Alcoholics Anonymous (AA) feature prominently in 12-step philosophy and culture and are one of the few documented explications of the cognitive, affective, and behavioral benefits that members might accrue. This study investigated the psychometric properties of a measure of AA's Twelve Promises and examined whether it mediated the effect of 12-step participation on abstinence. Young adults (N=302, M age 20.4 [1.6], range 18-25; 27% female; 95% White) enrolled in an addiction treatment effectiveness study completed assessments at intake and 3-, 6-, and 12-months post treatment including a 26-item, Twelve Promises Scale (TPS). Factor analyses examined the TPS' psychometrics and lagged mediational analyses tested the TPS as a mechanism of behavior change. Robust principal axis factoring extraction with Varimax rotation revealed a 2-factor solution explaining 45-58% of the variance across three administrations ("Psychological Wellbeing"=26-39%; "Freedom from Craving=17-21%); internal consistency was high (alpha=.83-.93). Both factors were found to increase in relation to greater 12-step participation, but significant mediation was found only for the Freedom from Craving factor explaining 21-34% of the effect of 12-step participation in increasing abstinence. The TPS shows potential as a conceptually relevant, and psychometrically sound measure and may be useful in helping elucidate the extent to which the Twelve Promises emerge as an independent benefit of 12-step participation and/or explain SUD remission and recovery. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Lakey, Brian; Orehek, Edward
2011-01-01
Perceived support is consistently linked to good mental health, which is typically explained as resulting from objectively supportive actions that buffer stress. Yet this explanation has difficulty accounting for the often-observed main effects between support and mental health. Relational regulation theory (RRT) hypothesizes that main effects…
Berkemeyer, Shoma
2010-07-01
Studies report on the association between obesity and oxidative stress, with and without additional diseases. Macrophages in adipocytes, and hypoxia in adipose tissue have been suggested to explain how obesity can relate to oxidative stress. The straight line hypothesis using the lactic acid trap construct has been put forward to explain how proton imbalance can relate to obesity. Proton imbalance has been also reported to associate with the production of reactive oxygen species by inhibition of mitochondrial energy production. This review brings together existing literature and concepts to explain how obesity can relate to oxidative stress via protons, uniquely for itself or, as often observed, in conglomeration of additional diseases. Copyright 2010 Elsevier Ltd. All rights reserved.
Creep, compaction and the weak rheology of major faults
Sleep, Norman H.; Blanpied, M.L.
1992-01-01
Field and laboratory observations suggest that the porosity within fault zones varies over earthquake cycles so that fluid pressure is in long-term equilibrium with hydrostatic fluid pressure in the country rock. Between earthquakes, ductile creep compacts the fault zone, increasing fluid pressure, and finally allowing frictional failure at relatively low shear stress. Earthquake faulting restores porosity and decreases fluid pressure to below hydrostatic. This mechanism may explain why major faults, such as the San Andreas system, are weak.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Samsonov, G. V.; Vitryanyuk, V. K.; Voronkin, M. A.
Physicomechanical properties of the hard alloy TiC -Ni--Mo (with content 3. 5, 10, and 25 mol.% relative to TiC) were studied as affected by its carbide phase alloying with niobium carbide. It is shown that an increase in the NbC content favors a rise in the bending strength to 132 kg/mm/sup 2/ and impact strength at practically unchanged hardness (91 HR.4), which is explained by some rise in the grain plasticity of the solid phase presenting the complex carbide TiC -NbC.
NASA Astrophysics Data System (ADS)
Konduru, R.; Gupta, A.; Matsumoto, J.; Takahashi, H. G.
2017-12-01
In order to explain monsoon circulation, surface temperature gradients described as most traditional concept. However, it cannot explain certain important aspects of monsoon circulation. Later, convective quasi-equilibrium framework and vertically integrated atmospheric energy budget has become recognized theories to explain the monsoon circulation. In this article, same theories were analyzed and observed for the duration 1979-2010 over south Asian summer monsoon region. With the help of NCEP-R2, NOAA 20th Century, and Era-Interim reanalysis an important feature was noticed pertained to subcloud layer entropy and vertical moist static energy. In the last 32 years, subcloud layer entropy and vertically integrated moist static energy has shown significant seasonal warming all over the region with peak over the poleward flank of the cross-equatorial cell. The important reason related to the warming was found to be increase in surface enthalpy fluxes. Instead, other dynamical contributions pertained to the warming was also observed. Increase in positive anomalies of vertical advection of moist static energy over northern Bay of Bengal, Central India, Peninsular India, Eastern Arabian Sea, and Equatorial Indian Ocean was found to be an important dynamic factor contributing for warming of vertically integrated moist static energy. Along with it vertical moist stability has also supported the argument. Similar interpretations were perceived in the AMIP simulation of CCSM4 model. Further modeling experiments on this warming will be helpful to know the exact mechanism behind it.
Pelegrín-Borondo, Jorge; Reinares-Lara, Eva; Olarte-Pascual, Cristina; Garcia-Sierra, Marta
2016-01-01
Today, technological implants are being developed to increase innate human capacities, such as memory or calculation speed, and to endow us with new ones, such as the remote control of machines. This study's aim was two-fold: first, to introduce a Cognitive-Affective-Normative (CAN) model of technology acceptance to explain the intention to use this technology in the field of consumer behavior; and second, to analyze the differences in the intention to use it based on whether the intended implant recipient is oneself or one's child (i.e., the moderating effect of the end user). A multi-group analysis was performed to compare the results between the two groups: implant “for me” (Group 1) and implant “for my child” (Group 2). The model largely explains the intention to use the insideable technology for the specified groups [variance explained (R2) of over 0.70 in both cases]. The most important variables were found to be “positive emotions” and (positive) “subjective norm.” This underscores the need to broaden the range of factors considered to be decisive in technology acceptance to include variables related to consumers' emotions. Moreover, statistically significant differences were found between the “for me” and “for my child” models for “perceived ease of use (PEU)” and “subjective norm.” These findings confirm the moderating effect of the end user on new insideable technology acceptance. PMID:26941662
Pyykkönen, Antti-Jussi; Räikkönen, Katri; Tuomi, Tiinamaija; Eriksson, Johan G; Groop, Leif; Isomaa, Bo
2012-05-01
To study whether the frequently reported association between depressive symptoms and the metabolic syndrome (MetS) and its individual components are secondary to the use of antidepressant medication and to established diabetes or cardiovascular diseases (CVD). A population-based, random sample of 4,967 women and men aged 18-75 years. MetS was defined according to the new, harmonized criteria. Glucose tolerance was assessed by oral glucose tolerance test (OGTT). CVD, depressive symptoms, and use of antidepressant medication were self-reported. The odds for having the MetS increased over 10%for each standard deviation increase in depressive symptoms. Users of antidepressant medication had more than 50% increased odds for having the MetS. Depressive symptoms were also associated with higher glucose response during the OGTT, higher serum triglyceride and lower HDL-cholesterol concentrations, and higher waist circumference, while use of antidepressant medication was associated with higher triglycerides, waist circumference, and systolic blood pressure. The associations of depressive symptoms were not secondary to use of antidepressant medication and were not explained by established diabetes or CVD. Depressive symptoms, the MetS, and the individual components of MetS are related. These associations are not driven by use of antidepressant medication, established diabetes, or CVD.
Collective-goal ascription increases cooperation in humans.
Mitkidis, Panagiotis; Sørensen, Jesper; Nielbo, Kristoffer L; Andersen, Marc; Lienard, Pierre
2013-01-01
Cooperation is necessary in many types of human joint activity and relations. Evidence suggests that cooperation has direct and indirect benefits for the cooperators. Given how beneficial cooperation is overall, it seems relevant to investigate the various ways of enhancing individuals' willingness to invest in cooperative endeavors. We studied whether ascription of a transparent collective goal in a joint action promotes cooperation in a group. A total of 48 participants were assigned in teams of 4 individuals to either a "transparent goal-ascription" or an "opaque goal-ascription" condition. After the manipulation, the participants played an anonymous public goods game with another member of their team. We measured the willingness of participants to cooperate and their expectations about the other player's contribution. Between subjects analyses showed that transparent goal ascription impacts participants' likelihood to cooperate with each other in the future, thereby greatly increasing the benefits from social interactions. Further analysis showed that this could be explained with a change in expectations about the partner's behavior and by an emotional alignment of the participants. The study found that a transparent goal ascription is associated with an increase of cooperation. We propose several high-level mechanisms that could explain the observed effect: general affect modulation, trust, expectation and perception of collective efficacy.
Cunningham, Peter J
2011-06-01
This study examines whether affordability thresholds for medical care as defined by families change over time. The results from two nationally representative surveys show that while financial stress from medical bills--defined as the percent with problems paying medical bills--increased between 2003 and 2007, greater out-of-pocket spending accounted for this increase only for higher-income persons with employer-sponsored insurance coverage. Increased spending did not account for an increase in medical bill problems among lower-income persons. Moreover, the increase in medical bill problems among low-income persons occurred at relatively low levels of out-of-pocket spending rather than at higher levels. The results suggest that "affordability thresholds" for medical care as defined by individuals and families are not stable over time, especially for lower-income persons, which has implications for setting affordability standards in health reform.
The Role of Resistance Exercise in Weight Loss.
ERIC Educational Resources Information Center
Alexander, Jeffrey L.
2002-01-01
Explains the role of weight training in weight loss, noting how weight training contributes to the creation of a negative energy balance and explaining how resistance exercise can cause an increase in fat oxidation, both acutely and chronically. Resistance exercise has an indirect impact on weight and fat loss through increasing resting metabolic…
Developmental Cascade Effects of the New Beginnings Program on Adolescent Adaptation Outcomes
Bonds, Darya D.; Wolchik, Sharlene A.; Winslow, Emily; Tein, Jenn-Yun; Sandler, Irwin N.; Millsap, Roger E.
2010-01-01
Using data from a 6-year longitudinal follow-up sample of 240 youth who participated in a randomized experimental trial of a preventive intervention for divorced families with children ages 9–12, the current study tested alternative cascading pathways by which the intervention decreased symptoms of internalizing disorders, symptoms of externalizing disorders, substance use, and risky sexual behavior, and increased self-esteem and academic performance in mid-to late-adolescence (15–19 years old). It was hypothesized that the impact of the program on adolescent adaptation outcomes would be explained by progressive associations between program-induced changes in parenting and youth adaptation outcomes. The results supported a cascading model of program effects in which the program was related to increased mother-child relationship quality, which was related to subsequent decreases in child internalizing problems, which then was related to subsequent increases in self-esteem and decreases in symptoms of internalizing disorders in adolescence. The results also were consistent with a model in which the program was related to increased maternal effective discipline, which was related to subsequent decreases in child externalizing problems, which then was related to subsequent decreases in symptoms of externalizing disorders, less substance use and better academic performance in adolescence. There were no significant differences in the model based on level of baseline risk or adolescent gender. These results provide support for a cascading pathways model of child and adolescent development. PMID:20883581
Effect of Game Management on Wild Red-Legged Partridge Abundance
Díaz-Fernández, Silvia; Arroyo, Beatriz; Casas, Fabián; Martinez-Haro, Monica; Viñuela, Javier
2013-01-01
The reduction of game and fish populations has increased investment in management practices. Hunting and fishing managers use several tools to maximize harvest. Managers need to know the impact their management has on wild populations. This issue is especially important to improve management efficacy and biodiversity conservation. We used questionnaires and field bird surveys in 48 hunting estates to assess whether red-legged partridge Alectoris rufa young/adult ratio and summer abundance were related to the intensity of management (provision of supplementary food and water, predator control and releases of farm-bred partridges), harvest intensity or habitat in Central Spain. We hypothesized that partridge abundance would be higher where management practices were applied more intensively. Variation in young/adult ratio among estates was best explained by habitat, year and some management practices. Density of feeders and water points had a positive relationship with this ratio, while the density of partridges released and magpies controlled were negatively related to it. The variables with greatest relative importance were feeders, releases and year. Variations in post-breeding red-legged partridge abundance among estates were best explained by habitat, year, the same management variables that influenced young/adult ratio, and harvest intensity. Harvest intensity was negatively related to partridge abundance. The other management variables had the same type of relationship with abundance as with young/adult ratio, except magpie control. Variables with greatest relative importance were habitat, feeders, water points, releases and harvest intensity. Our study suggests that management had an overall important effect on post-breeding partridge abundance. However, this effect varied among tools, as some had the desired effect (increase in partridge abundance), whereas others did not or even had a negative relationship (such as release of farm-reared birds) and can be thus considered inefficient or even detrimental. We advise reconsidering their use from both ecological and economical points of view. PMID:23840515
Kirsten, Holger; Al-Hasani, Hoor; Holdt, Lesca; Gross, Arnd; Beutner, Frank; Krohn, Knut; Horn, Katrin; Ahnert, Peter; Burkhardt, Ralph; Reiche, Kristin; Hackermüller, Jörg; Löffler, Markus; Teupser, Daniel; Thiery, Joachim; Scholz, Markus
2015-08-15
Genetics of gene expression (eQTLs or expression QTLs) has proved an indispensable tool for understanding biological pathways and pathomechanisms of trait-associated SNPs. However, power of most genome-wide eQTL studies is still limited. We performed a large eQTL study in peripheral blood mononuclear cells of 2112 individuals increasing the power to detect trans-effects genome-wide. Going beyond univariate SNP-transcript associations, we analyse relations of eQTLs to biological pathways, polygenetic effects of expression regulation, trans-clusters and enrichment of co-localized functional elements. We found eQTLs for about 85% of analysed genes, and 18% of genes were trans-regulated. Local eSNPs were enriched up to a distance of 5 Mb to the transcript challenging typically implemented ranges of cis-regulations. Pathway enrichment within regulated genes of GWAS-related eSNPs supported functional relevance of identified eQTLs. We demonstrate that nearest genes of GWAS-SNPs might frequently be misleading functional candidates. We identified novel trans-clusters of potential functional relevance for GWAS-SNPs of several phenotypes including obesity-related traits, HDL-cholesterol levels and haematological phenotypes. We used chromatin immunoprecipitation data for demonstrating biological effects. Yet, we show for strongly heritable transcripts that still little trans-chromosomal heritability is explained by all identified trans-eSNPs; however, our data suggest that most cis-heritability of these transcripts seems explained. Dissection of co-localized functional elements indicated a prominent role of SNPs in loci of pseudogenes and non-coding RNAs for the regulation of coding genes. In summary, our study substantially increases the catalogue of human eQTLs and improves our understanding of the complex genetic regulation of gene expression, pathways and disease-related processes. © The Author 2015. Published by Oxford University Press.
NASA Astrophysics Data System (ADS)
Nehyba, Slavomír
2018-02-01
Two coarse-grained Gilbert-type deltas in the Lower Badenian deposits along the southern margin of the Western Carpathian Foredeep (peripheral foreland basin) were newly interpreted. Facies characterizing a range of depositional processes are assigned to four facies associations — topset, foreset, bottomset and offshore marine pelagic deposits. The evidence of Gilbert deltas within open marine deposits reflects the formation of a basin with relatively steep margins connected with a relative sea level fall, erosion and incision. Formation, progradation and aggradation of the thick coarse-grained Gilbert delta piles generally indicate a dramatic increase of sediment supply from the hinterland, followed by both relatively continuous sediment delivery and an increase in accommodation space. Deltaic deposition is terminated by relatively rapid and extended drowning and is explained as a transgressive event. The lower Gilbert delta was significantly larger, more areally extended and reveals a more complicated stratigraphic architecture than the upper one. Its basal surface represents a sequence boundary and occurs around the Karpatian/Badenian stratigraphic limit. Two coeval deltaic branches were recognized in the lower delta with partly different stratigraphic arrangements. This different stratigraphic architecture is mostly explained by variations in the sediment delivery and /or predisposed paleotopography and paleobathymetry of the basin floor. The upper delta was recognized only in a restricted area. Its basal surface represents a sequence boundary probably reflecting a higher order cycle of a relative sea level rise and fall within the Lower Badenian. Evidence of two laterally and stratigraphically separated coarse-grained Gilbert deltas indicates two regional/basin wide transgressive/regressive cycles, but not necessarily of the same order. Provenance analysis reveals similar sources of both deltas. Several partial source areas were identified (Mesozoic carbonates of the Northern Calcareous Alps and the Western Carpathians, crystalline rocks of the eastern margin of the Bohemian Massif, older sedimentary infill of the Carpathian Foredeep and/or the North Alpine Foreland Basin, sedimentary rocks of the Western Carpathian/Alpine Flysch Zone).
[Obstructive sleep apnea syndrome, hypertension and artery].
Baguet, Jean-Philippe; Barone-Rochette, Gilles; Pépin, Jean-Louis
2009-04-01
Obstructive sleep apnea syndrome (OSAS), due to upper airway collapse, is frequent but still underestimated. The dose-response relation between OSAS and hypertension (HTN) is now well established. Logically, therefore, blood pressure must be tested in every apneic patient, if necessary by ambulatory blood pressure monitoring. Multiple mechanisms explain this relation, most importantly the increase in sympathetic activity during apnea episodes. OSAS-related hypertension has several characteristics: it is highly prevalent, predominantly diastolic and nocturnal, and frequently affects non-dippers; and the HTN tends to be resistant to treatment. OSAS promotes the formation of arterial lesions (parietal thickening of the carotid artery, increased aortic stiffness, and endothelial dysfunction); the more severe the OSAS, the more severe the lesions. The beneficial effects on blood pressure of continuous positive airway pressure (CPAP), the benchmark treatment for OSAS, are still debated but appear to be significant for untreated or refractory hypertension, for severe OSAS, and when CPAP compliance is good. It also seems promising for the reduction of arterial lesions linked to OSAS.
Occupational Risk for Oral Cancer in Nordic Countries.
Tarvainen, Laura; Suojanen, Juho; Kyyronen, Pentti; Lindqvist, Christian; Martinsen, Jan Ivar; Kjaerheim, Kristina; Lynge, Elsebeth; Sparen, Par; Tryggvadottir, Laufey; Weiderpass, Elisabete; Pukkala, Eero
2017-06-01
To evaluate occupational risk for cancer of the tongue, oral cavity or pharynx after adjustment for alcohol and tobacco use. The data covered 14.9 million people and 28,623 cases of cancer of the tongue, oral cavity and pharynx in the Nordic countries 1961-2005. Alcohol consumption by occupation was estimated based on mortality from liver cirrhosis and incidence of liver cancer. Smoking by occupation was estimated based on the incidence of lung cancer. Only few occupations had relative risks of over 1.5 for cancer of the tongue, oral cavity and pharynx. These occupations included dentists, artistic workers, hairdressers, journalists, cooks and stewards, seamen and waiters. Several occupational categories, including dentists, had an increased relative risk of tongue cancer. This new finding remains to be explained but could be related to occupational chemical exposures, increased consumption of alcohol and tobacco products, or infection with human papilloma virus. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Nonkin in older adults' personal networks: more important among later cohorts?
Suanet, Bianca; van Tilburg, Theo G; Broese van Groenou, Marjolein I
2013-07-01
Research on age-related changes in personal networks has found compelling evidence for socioemotional selectivity theory and exchange theory holding that older adults experience a decline in less emotionally close nonkin relations as they age. However, recent societal developments are likely to have increased the salience of nonkin relations. We hypothesize that age-related decline in the proportion of nonkin in personal networks has been delayed or is slower in late birth cohorts of older adults compared with earlier cohorts. Seven observations by the Longitudinal Aging Study Amsterdam covering a time span of 17 years since 1992 were analyzed using multilevel regression analysis. The sample had 12,949 person-year observations from 3,516 respondents born between 1908 and 1937. Age-related decline in the proportion of nonkin is absent for cohorts born after 1922 and large for cohorts born in 1922 and before. Mediating variables for health and other resources did not explain cohort differences in age-related change. The salience of nonkin relationships is likely to have increased due to societal changes, resulting in absence or delay of decline in later cohorts. The findings raise the need for a reevaluation of old age and the creation of new theoretical perspectives.
Family and Cultural Processes Linking Family Instability to Mexican American Adolescents' Adjustment
Vargas, Danyel A.; Roosa, Mark W.; Knight, George P.; O'Donnell, Megan
2013-01-01
Despite the rapidly growing Mexican American population, no studies to date have attempted to explain the underlying relations between family instability and Mexican American children's development. Using a diverse sample of 740 Mexican American adolescents (49% female; 5th grade M age = 10.4; 7th grade M age = 12.8) and their mothers, we prospectively examined the relations between family instability and adolescent academic outcomes and mental health in the 7th grade. The model fit the data well and results indicated that family instability between 5th and 7th grade was related to increased 7th grade mother-adolescent conflict and in turn, mother-adolescent conflict was related to decreased school attachment and to increased externalizing and internalizing symptoms in the 7th grade. Results also indicated that 7th grade mother-adolescent conflict mediated the relations between family instability and 7th grade academic outcomes and mental health. Further, we explored adolescent familism values as a moderator and found that adolescent familism values served as a protective factor in the relation between mother-adolescent conflict and grades. Implications for future research and intervention strategies are discussed. PMID:23750521
Relation of nitrate concentrations to baseflow in the Raccoon River, Iowa
Schilling, K.E.; Lutz, D.S.
2004-01-01
Excessive nitrate-nitrogen (nitrate) export from the Raccoon River in west central Iowa is an environmental concern to downstream receptors. The 1972 to 2000 record of daily streamflow and the results from 981 nitrate measurements were examined to describe the relation of nitrate to streamflow in the Raccoon River. No long term trends in streamflow and nitrate concentrations were noted in the 28-year record. Strong seasonal patterns were evident in nitrate concentrations, with higher concentrations occurring in spring and fall. Nitrate concentrations were linearly related to streamflow at daily, monthly, seasonal, and annual time scales. At all time scales evaluated, the relation was improved when baseflow was used as the discharge variable instead of total streamflow. Nitrate concentrations were found to be highly stratified according to flow, but there was little relation of nitrate to streamflow within each flow range. Simple linear regression models developed to predict monthly mean nitrate concentrations explained as much as 76 percent of the variability in the monthly nitrate concentration data for 2001. Extrapolation of current nitrate baseflow relations to historical conditions in the Raccoon River revealed that increasing baseflow over the 20th century could account for a measurable increase in nitrate concentrations.
NASA Astrophysics Data System (ADS)
Kaboli, Shirin; McDermid, Joseph R.
2014-08-01
A galvanizing simulator was used to determine the effect of galvanizing bath antimony (Sb) content, substrate surface roughness, and cooling rate on the microstructural development of metallic zinc coatings. Substrate surface roughness was varied through the use of relatively rough hot-rolled and relatively smooth bright-rolled steels, cooling rates were varied from 0.1 to 10 K/s, and bulk bath Sb levels were varied from 0 to 0.1 wt pct. In general, it was found that increasing bath Sb content resulted in coatings with a larger grain size and strongly promoted the development of coatings with the close-packed {0002} basal plane parallel to the substrate surface. Increasing substrate surface roughness tended to decrease the coating grain size and promoted a more random coating crystallographic texture, except in the case of the highest Sb content bath (0.1 wt pct Sb), where substrate roughness had no significant effect on grain size except at higher cooling rates (10 K/s). Increased cooling rates tended to decrease the coating grain size and promote the {0002} basal orientation. Calculations showed that increasing the bath Sb content from 0 to 0.1 wt pct Sb increased the dendrite tip growth velocity from 0.06 to 0.11 cm/s by decreasing the solid-liquid interface surface energy from 0.77 to 0.45 J/m2. Increased dendrite tip velocity only partially explains the formation of larger zinc grains at higher Sb levels. It was also found that the classic nucleation theory cannot completely explain the present experimental observations, particularly the effect of increasing the bath Sb, where the classical theory predicts increased nucleation and a finer grain size. In this case, the "poisoning" theory of nucleation sites by segregated Sb may provide a partial explanation. However, any analysis is greatly hampered by the lack of fundamental thermodynamic information such as partition coefficients and surface energies and by a lack of fundamental structural studies. Overall, it was concluded that the fundamental mechanisms behind the microstructural development of solidified metallic zinc coatings have yet to be completely elucidated and require further investigation.
Ramsey, Elijah W.; Hodgson, M.E.; Sapkota, S.K.; Nelson, G.A.
2001-01-01
An empirical model was used to relate forest type and hurricane-impact distribution with wind speed and duration to explain the variation of hurricane damage among forest types along the Atchafalaya River basin of coastal Louisiana. Forest-type distribution was derived from Landsat Thematic Mapper image data, hurricane-impact distribution from a suite of transformed advanced very high resolution radiometer images, and wind speed and duration from a wind-field model. The empirical model explained 73%, 84%, and 87% of the impact variances for open, hardwood, and cypress-tupelo forests, respectively. These results showed that the estimated impact for each forest type was highly related to the duration and speed of extreme winds associated with Hurricane Andrew in 1992. The wind-field model projected that the highest wind speeds were in the southern basin, dominated by cypress-tupelo and open forests, while lower wind speeds were in the northern basin, dominated by hardwood forests. This evidence could explain why, on average, the impact to cypress-tupelos was more severe than to hardwoods, even though cypress-tupelos are less susceptible to wind damage. Further, examination of the relative importance of wind speed in explaining the impact severity to each forest type showed that the impact to hardwood forests was mainly related to tropical-depression to tropical-storm force wind speeds. Impacts to cypress-tupelo and open forests (a mixture of willows and cypress-tupelo) were broadly related to tropical-storm force wind speeds and by wind speeds near and somewhat in excess of hurricane force. Decoupling the importance of duration from speed in explaining the impact severity to the forests could not be fully realized. Most evidence, however, hinted that impact severity was positively related to higher durations at critical wind speeds. Wind-speed intervals, which were important in explaining the impact severity on hardwoods, showed that higher durations, but not the highest wind speeds, were concentrated in the northern basin, dominated by hardwoods. The extreme impacts associated with the cypress-tupelo forests in the southeast corner of the basin intersected the highest durations as well as the highest wind speeds. ?? 2001 Published by Elsevier Science Inc.
Chimpanzees and bonobos differ in intrinsic motivation for tool use.
Koops, Kathelijne; Furuichi, Takeshi; Hashimoto, Chie
2015-06-16
Tool use in nonhuman apes can help identify the conditions that drove the extraordinary expansion of hominin technology. Chimpanzees and bonobos are our closest living relatives. Whereas chimpanzees are renowned for their tool use, bonobos use few tools and none in foraging. We investigated whether extrinsic (ecological and social opportunities) or intrinsic (predispositions) differences explain this contrast by comparing chimpanzees at Kalinzu (Uganda) and bonobos at Wamba (DRC). We assessed ecological opportunities based on availability of resources requiring tool use. We examined potential opportunities for social learning in immature apes. Lastly, we investigated predispositions by measuring object manipulation and object play. Extrinsic opportunities did not explain the tool use difference, whereas intrinsic predispositions did. Chimpanzees manipulated and played more with objects than bonobos, despite similar levels of solitary and social play. Selection for increased intrinsic motivation to manipulate objects likely also played an important role in the evolution of hominin tool use.
Plant root proliferation in nitrogen-rich patches confers competitive advantage
Robinson, D.; Hodge, A.; Griffiths, B. S.; Fitter, A. H.
1999-01-01
Plants respond strongly to environmental heterogeneity, particularly below ground, where spectacular root proliferations in nutrient-rich patches may occur. Such 'foraging' responses apparently maximize nutrient uptake and are now prominent in plant ecological theory. Proliferations in nitrogen-rich patches are difficult to explain adaptively, however. The high mobility of soil nitrate should limit the contribution of proliferation to N capture. Many experiments on isolated plants show only a weak relation between proliferation and N uptake. We show that N capture is associated strongly with proliferation during interspecific competition for finite, locally available, mixed N sources, precisely the conditions under which N becomes available to plants on generally infertile soils. This explains why N-induced root proliferation is an important resource-capture mechanism in N-limited plant communities and suggests that increasing proliferation by crop breeding or genetic manipulation will have a limited impact on N capture by well-fertilized monocultures.
[Causal inference in medicine--a historical view in epidemiology].
Tsuda, T; Babazono, A; Mino, Y; Matsuoka, H; Yamamoto, E
1996-07-01
Changes of causal inference concepts in medicine, especially those having to do with chronic diseases, were reviewed. The review is divided into five sections. First, several articles on the increased academic acceptance of observational research are cited. Second, the definitions of confounder and effect modifier concepts are explained. Third, the debate over the so-called "criteria for causal inference" was discussed. Many articles have pointed out various problems related to the lack of logical bases for standard criteria, however, such criteria continue to be misapplied in Japan. Fourth, the Popperian and verificationist concepts of causal inference are summarized. Lastly, a recent controversy on meta-analysis is explained. Causal inference plays an important role in epidemiologic theory and medicine. However, because this concept has not been well-introduced in Japan, there has been much misuse of the concept, especially when used for conventional criteria.
Vaccine hesitancy, refusal and access barriers: The need for clarity in terminology.
Bedford, Helen; Attwell, Katie; Danchin, Margie; Marshall, Helen; Corben, Paul; Leask, Julie
2017-08-19
Although vaccination uptake is high in most countries, pockets of sub-optimal coverage remain posing a threat to individual and population immunity. Increasingly, the term 'vaccine hesitancy' is being used by experts and commentators to explain sub-optimal vaccination coverage. We contend that using this term to explain all partial or non-immunisation risks generating solutions that are a poor match for the problem in a particular community or population. We propose more precision in the term 'vaccine hesitancy' is needed particularly since much under-vaccination arises from factors related to access or pragmatics. Only with clear terminology can we begin to understand where the problem lies, measure it accurately and develop appropriate interventions. This will ensure that our interventions have the best chance of success to make vaccines available to those who want them and in helping those who are uncertain about their vaccination decision. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kozlov, Andrei S; Andor-Ardó, Daniel; Hudspeth, A J
2012-02-21
The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer's micromechanics and of the associated noise. Using microrheology, we characterize the statistics of this noise; exploiting the fluctuation-dissipation theorem, we determine the associated micromechanics. The statistics reveal unusual Brownian motion in which the mean square displacement increases as a fractional power of time, indicating that the mechanisms governing energy dissipation are related to those of energy storage. This anomalous scaling contradicts the canonical model of mechanoelectrical transduction, but the results can be explained if the micromechanics incorporates viscoelasticity, a salient characteristic of biopolymers. We amend the canonical model and demonstrate several consequences of viscoelasticity for sensory coding.
Kozlov, Andrei S.; Andor-Ardó, Daniel; Hudspeth, A. J.
2012-01-01
The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer’s micromechanics and of the associated noise. Using microrheology, we characterize the statistics of this noise; exploiting the fluctuation-dissipation theorem, we determine the associated micromechanics. The statistics reveal unusual Brownian motion in which the mean square displacement increases as a fractional power of time, indicating that the mechanisms governing energy dissipation are related to those of energy storage. This anomalous scaling contradicts the canonical model of mechanoelectrical transduction, but the results can be explained if the micromechanics incorporates viscoelasticity, a salient characteristic of biopolymers. We amend the canonical model and demonstrate several consequences of viscoelasticity for sensory coding. PMID:22328158
Universal Behavior of Extreme Price Movements in Stock Markets
Fuentes, Miguel A.; Gerig, Austin; Vicente, Javier
2009-01-01
Many studies assume stock prices follow a random process known as geometric Brownian motion. Although approximately correct, this model fails to explain the frequent occurrence of extreme price movements, such as stock market crashes. Using a large collection of data from three different stock markets, we present evidence that a modification to the random model—adding a slow, but significant, fluctuation to the standard deviation of the process—accurately explains the probability of different-sized price changes, including the relative high frequency of extreme movements. Furthermore, we show that this process is similar across stocks so that their price fluctuations can be characterized by a single curve. Because the behavior of price fluctuations is rooted in the characteristics of volatility, we expect our results to bring increased interest to stochastic volatility models, and especially to those that can produce the properties of volatility reported here. PMID:20041178
Hall effect analysis in irradiated silicon samples with different resistivities
NASA Astrophysics Data System (ADS)
Borchi, E.; Bruzzi, M.; Dezillie, B.; Lazanu, S.; Li, Z.; Pirollo, S.
1999-08-01
The changes induced by neutron irradiation in n- and p-type silicon samples with starting resistivities from 10 /spl Omega/-cm up to 30 k/spl Omega/-cm, grown using different techniques, as float-zone (FZ), Czochralski (CZ) and epitaxial, have been analyzed by Van der Pauw and Hall effect measurements. Increasing the fluence, each set of samples evolves toward a quasi-intrinsic p-type material. This behavior has been explained in the frame of a two-level model, that considers the introduction during irradiation of mainly two defects. A deep acceptor and a deep donor, probably related to the divacancy and to the C/sub i/O/sub i/ complex, are placed in the upper and lower half of the forbidden gap, respectively. This simple model explains quantitatively the data on resistivity and Hall coefficient of each set of samples up to the fluence of /spl ap/10/sup 14/ n/cm/sup 2/.
Issues of doing gender and doing technology - Music as an innovative theme for technology education
NASA Astrophysics Data System (ADS)
Thaler, A.; Zorn, I.
2010-08-01
This paper presents the concept and results of the research project 'Engineer Your Sound!' (2008-2009). It aimed at exploring whether interdisciplinary, innovative teaching/learning settings in the fields of technology and digital media can be used to give pupils the opportunities to experiment and discover their technical potential, skills, interests and talents and if music technology could offer such an appealing context. The paper explains how technology and why gender need to be addressed when planning to raise young people's interest in technology but questions if interest in technology is mainly influenced by gender. The paper explores through ethnographic research how pupils' technological competencies and interests have developed during the course of a technology-related project. Results of the analysis explain how music technology can serve as a suitable theme with the potential to increase both males' and females' interest in technology.
Pitzer, Virginia E; Feasey, Nicholas A; Msefula, Chisomo; Mallewa, Jane; Kennedy, Neil; Dube, Queen; Denis, Brigitte; Gordon, Melita A; Heyderman, Robert S
2015-11-01
Multiyear epidemics of Salmonella enterica serovar Typhi have been reported from countries across eastern and southern Africa in recent years. In Blantyre, Malawi, a dramatic increase in typhoid fever cases has recently occurred, and may be linked to the emergence of the H58 haplotype. Strains belonging to the H58 haplotype often exhibit multidrug resistance and may have a fitness advantage relative to other Salmonella Typhi strains. To explore hypotheses for the increased number of typhoid fever cases in Blantyre, we fit a mathematical model to culture-confirmed cases of Salmonella enterica infections at Queen Elizabeth Central Hospital, Blantyre. We explored 4 hypotheses: (1) an increase in the basic reproductive number (R0) in response to increasing population density; (2) a decrease in the incidence of cross-immunizing infection with Salmonella Enteritidis; (3) an increase in the duration of infectiousness due to failure to respond to first-line antibiotics; and (4) an increase in the transmission rate following the emergence of the H58 haplotype. Increasing population density or decreasing cross-immunity could not fully explain the observed pattern of typhoid emergence in Blantyre, whereas models allowing for an increase in the duration of infectiousness and/or the transmission rate of typhoid following the emergence of the H58 haplotype provided a good fit to the data. Our results suggest that an increase in the transmissibility of typhoid due to the emergence of drug resistance associated with the H58 haplotype may help to explain recent outbreaks of typhoid in Malawi and similar settings in Africa. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.
Haefliger, I O; von Arx, G; Pimentel, A-R
2010-04-01
The aim of this study was to assess the pathophysiological mechanisms leading to intraocular pressure (IOP) increase and to review the prevalence of glaucoma in thyroid eye disease (TED), an autoimmune reaction affecting extra-ocular muscles and intra-orbital content in thyrotoxicosis (Grave's disease, hyperthyroidism). We applied the modified Friedenswald's and Goldmann's equations to explain the mechanisms by which IOP increases in TED and gave a brief review of the literature. In TED, Friedenswald's equation explains the ultra-short term IOP increase observed when eyes deviate from their primary gaze position (eyeball compression by enlarged and infiltrated extra-ocular muscles). Goldmann's equation explains the long-term IOP increase seen in TED (episcleral venous pressure elevation secondary to intraorbital content and pressure increase). Most studies did not find a significant increase in glaucoma prevalence in patients with TED. In TED, glaucoma prevalence does not seem to be significantly increased and, from a pathophysiological standpoint, the long-term IOP increase is essentially due to episcleral venous pressure elevation. Copyright Georg Thieme Verlag KG Stuttgart . New York.
Tredennick, Andrew T; Adler, Peter B; Adler, Frederick R
2017-08-01
Theory relating species richness to ecosystem variability typically ignores the potential for environmental variability to promote species coexistence. Failure to account for fluctuation-dependent coexistence may explain deviations from the expected negative diversity-ecosystem variability relationship, and limits our ability to predict the consequences of increases in environmental variability. We use a consumer-resource model to explore how coexistence via the temporal storage effect and relative nonlinearity affects ecosystem variability. We show that a positive, rather than negative, diversity-ecosystem variability relationship is possible when ecosystem function is sampled across a natural gradient in environmental variability and diversity. We also show how fluctuation-dependent coexistence can buffer ecosystem functioning against increasing environmental variability by promoting species richness and portfolio effects. Our work provides a general explanation for variation in observed diversity-ecosystem variability relationships and highlights the importance of conserving regional species pools to help buffer ecosystems against predicted increases in environmental variability. © 2017 John Wiley & Sons Ltd/CNRS.
Gonzales, Nancy A.; Germán, Miguelina; Kim, Su Yeong; George, Preethy; Fabrett, Fairlee C.; Millsap, Roger; Dumka, Larry E.
2009-01-01
This study of 598 7th grade students of Mexican origin examined the role of traditional cultural values as a mediator of the effects of immigrant status, Mexican cultural orientation and Anglo cultural orientation on adolescent externalizing behavior and academic engagement. Immigrant status of adolescents and their maternal caregivers uniquely predicted increased Mexican cultural orientation and decreased Anglo cultural orientation, and both Mexican and Anglo cultural orientation related positively to adolescents” endorsement of traditional cultural values. Endorsement of traditional cultural values related, in turn, to decreased externalizing behaviors and increased academic engagement and these findings were replicated across adolescent and teacher report of these two outcomes. Tests of mediation provided further evidence to support these pathways. Findings support the central importance of traditional cultural values as a protective resource that explains why immigrant youth exhibit fewer externalizing problems and increased academic engagement when compared to their second and third generation peers. PMID:18085435
NASA Astrophysics Data System (ADS)
Prywer, Jolanta; Mielniczek-Brzóska, Ewa; Olszynski, Marcin
2015-05-01
Effect of trisodium citrate on the crystallization of struvite was studied. To evaluate such an effect an experiment of struvite growth from artificial urine was performed. The investigations are related to infectious urinary stones formation. The crystallization process was induced by the addition of aqueous ammonia solution to mimic the bacterial activity. The spectrophotometric results demonstrate that trisodium citrate increases induction time with respect to struvite formation and decreases the growth efficiency of struvite. The inhibitory effect of trisodium citrate on the nucleation and growth of struvite is explained in base of chemical speciation analysis. Such an analysis demonstrates that the inhibitory effect is related with the fact that trisodium citrate binds NH4 + and Mg2+ ions in the range of pH from 7 to 9.5 characteristic for struvite precipitation. The most important is the MgCit- complex whose concentration strongly depends on an increase in pH rather than on an increase in citrate concentrations.
Different sensitivities of snowpacks to warming in Mediterranean climate mountain areas
NASA Astrophysics Data System (ADS)
López-Moreno, J. I.; Gascoin, S.; Herrero, J.; Sproles, E. A.; Pons, M.; Alonso-González, E.; Hanich, L.; Boudhar, A.; Musselman, K. N.; Molotch, N. P.; Sickman, J.; Pomeroy, J.
2017-07-01
In this study we quantified the sensitivity of snow to climate warming in selected mountain sites having a Mediterranean climate, including the Pyrenees in Spain and Andorra, the Sierra Nevada in Spain and California (USA), the Atlas in Morocco, and the Andes in Chile. Meteorological observations from high elevations were used to simulate the snow energy and mass balance (SEMB) and calculate its sensitivity to climate. Very different climate sensitivities were evident amongst the various sites. For example, reductions of 9%-19% and 6-28 days in the mean snow water equivalent (SWE) and snow duration, respectively, were found per °C increase. Simulated changes in precipitation (±20%) did not affect the sensitivities. The Andes and Atlas Mountains have a shallow and cold snowpack, and net radiation dominates the SEMB; and explains their relatively low sensitivity to climate warming. The Pyrenees and USA Sierra Nevada have a deeper and warmer snowpack, and sensible heat flux is more important in the SEMB; this explains the much greater sensitivities of these regions. Differences in sensitivity help explain why, in regions where climate models project relatively greater temperature increases and drier conditions by 2050 (such as the Spanish Sierra Nevada and the Moroccan Atlas Mountains), the decline in snow accumulation and duration is similar to other sites (such as the Pyrenees and the USA Sierra Nevada), where models project stable precipitation and more attenuated warming. The snowpack in the Andes (Chile) exhibited the lowest sensitivity to warming, and is expected to undergo only moderate change (a decrease of <12% in mean SWE, and a reduction of < 7 days in snow duration under RCP 4.5). Snow accumulation and duration in the other regions are projected to decrease substantially (a minimum of 40% in mean SWE and 15 days in snow duration) by 2050.
den Hoed, M; Westerterp, K R
2008-08-01
Activity-related energy expenditure is the most variable component of total energy expenditure and thus an important determinant of energy balance. To determine whether body composition is related to physical activity in both men and women. A total of 134 healthy participants were recruited (80 women, 54 men; aged 21+/-2 years; body mass index, 22.0+/-2.4). Physical activity was measured for a period of 2 weeks using a triaxial accelerometer for movement registration (Tracmor). Percentage body fat (%BF) was determined by underwater weighing and deuterium dilution according to Siri's three-compartment model. The participant characteristics-body mass, height and gender together explained a substantial part of the variation in %BF (R(2)=0.75, SEE=4.0%). Adding physical activity to the model increased the explained variation in %BF with 4% (R(2)=0.79, SEE=3.7%, P<0.001). Taking seasonality into account by adding the number of daylight hours as an independent variable further increased the explained variation with 1% (R(2)=0.80, SEE=3.7%, P<0.05). In analogy, the association was evaluated for both genders separately. In women, %BF and physical activity were significantly associated (P<0.001). In men, %BF was only associated with physical activity when seasonality was taken into account as well (P<0.05). This probably resulted from men participating more in season bound sports, because an association was found without adjusting for seasonality when only men with a consistent year-round participation in sports were considered. Evidence was found for an association between body composition and physical activity in both genders. A consistent year-round degree of physical activity appears to be a prerequisite to reveal the association. Moreover, Tracmor-assessed physical activity improves the estimate of %BF when a participant's characteristics are taken into account.
The Geomagnetic Field and Correlations with Multiple Sclerosis: A Possible Etiology of Disease
NASA Astrophysics Data System (ADS)
Wade, Brett
Multiple sclerosis (MS) is a complex autoimmune disease that results in a demyelinating process of the central nervous system. It is the most common, progressive, neurological disease affecting young adults, and there is no cure. A curious feature of MS is its distinct global prevalence with high rates of occurrence between 40 and 60 degrees latitude. While genetics may partially explain this phenomenon, studies have shown that the influence of genetics is modest. Many non-genetic variables, such as viruses, vitamin D, smoking, diet, hormones, etc., have been shown to be related to the expression of MS but none of these variables have been determined to be necessarily strong enough to exclude other factors. The geomagnetic field, which is a non-uniform, three dimensional entity which protects all living things from ionizing radiation, is suggested in this research to be related to global MS prevalence. This study hypothesized that either the total field, the vertical field, or the horizontal field strength of the geomagnetic field will be correlated with MS. Using secondary sources of prevalence studies (N=131) and geomagnetic data, the results supported all three hypotheses with the strongest correlation being an inverse relationship between the horizontal field and MS (r = -.607). The explanation for the inverse relationship being most strongly correlated with MS prevalence is explained by the fact that the horizontal aspect of the geomagnetic field has a protective effect from incoming cosmic radiation. Chronic exposure to high levels of background radiation can have deleterious health effects. This research suggests that living in areas of a weak horizontal field increases a person's exposure to ionizing radiation and therefore increases the risk for developing MS. While it was not the intention of this research, it became clear that an explanation which explained the results of this research and also attempted to unify the mechanisms of all non-genetic variables was prudent. A Unified Theory of MS Disease Expression is presented in this research.
Sato, Yasuto; Kiyohara, Kosuke; Kojimahara, Noriko; Yamaguchi, Naohito
2016-07-01
The aim of this study was to examine whether incidence of malignant neoplasms of the central nervous system from 1993 to 2010 has increased among young people in Japan, and whether the increase could be explained by increase in mobile phone use. Joinpoint regression analysis of incidence data was performed. Subsequently, the expected incidence rate was calculated assuming that the relative risk was 1.4 for those who used mobile phones more than 1640 h cumulatively. Annual percent change was 3.9% (95% confidence interval [CI], 1.6-6.3) for men in their 20s from 1993 to 2010, 12.3% (95% CI, 3.3-22.1) for women in their 20s from 2002 to 2010, 2.7% (95% CI, 1.3-4.1) for men in their 30s from 1993 to 2010, and 3.0% (95% CI, 1.4-4.7) for women in their 30s from 1993 to 2010. Change in incidence rates from 1993 to 2010 was 0.92 per 100,000 people for men in their 20s, 0.83 for women in their 20s, 0.89 for men in their 30s, and 0.74 for women in their 30s. Change in expected incidence rates from 1993 to 2010 was 0.08 per 100,000 people for men in their 20s, 0.03 for women in their 20s, 0.15 for men in their 30s, and 0.05 for women in their 30s. Patterns in sex-, age-, and period-specific incidence increases are inconsistent with sex-, age-, and period-specific prevalence trends, suggesting the overall incidence increase cannot be explained by heavy mobile phone use. Bioelectromagnetics. 37:282-289, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
The development of the Professional Values Model in Nursing.
Kaya, Ayla; Boz, İlkay
2017-01-01
One of the most important criteria for professionalism is accumulation of knowledge that is usable in professional practice. Nursing models and theories are important elements of accumulating nursing knowledge and have a chance to guarantee the ethical professional practice. In recent years, there has been an increase in the use of models in nursing research and newly created terminology has started to be used in nursing. In this study, a new model, termed as the Professional Values Model, developed by the authors was described. Concepts comprising the conceptual framework of the model and relations between the concepts were explained. It is assumed that awareness about concepts of the model will increase not only the patients' satisfaction with nursing care, but also the nurses' job satisfaction and quality of nursing care. Contemporary literature has been reviewed and synthesized to develop this theoretical paper on the Professional Values Model in nursing. Having high values in nursing increases job satisfaction, which results in the improvement of patient care and satisfaction. Also, individual characteristics are effective in the determination of individual needs, priorities, and values. This relation, proved through research about the Professional Values Model, has been explained. With development of these concepts, individuals' satisfaction with care and nurses' job satisfaction will be enhanced, which will increase the quality of nursing care. Most importantly, nurses can take proper decisions about ethical dilemmas and take ethical action when they take these values into consideration when giving care. The Professional Values Model seems suitable for nurse managers and it is expected that testing will improve it. Implementation of the Professional Values Model by nurse managers may increase motivation of nurses they work with. It is suggested that guidance by the Professional Values Model may help in enhancement of motivation efforts of the nurse managers and therefore should be taken into account.
NASA Astrophysics Data System (ADS)
Bertin, Xavier; Chaumillon, Eric; Sottolichio, Aldo; Pedreros, Rodrigo
2005-06-01
Tidal inlet characteristics are controlled by wave energy, tidal range, tidal prism, sediment supply and direction and rates of sand delivered to the inlet. This paper deals with the relations between inlet and lagoon evolutions, linked by the tidal prism. Our study is focused on the Maumusson Inlet and the Marennes-Oléron Bay (first oyster farming area in Europe), located on the western coast of France. The tidal range (2-6 m) and wave climate (mean height: 1.5 m) place this tidal inlet system in the mixed energy (tide, waves), tide-dominated category. The availability of high-resolution bathymetric data since 1824 permits to characterise and quantify accurately morphological changes of both the inlet and the tidal bay. Since 1824, sediment filling of the tidal bay has led to a 20% decrease in its water volume, and a 35% reduction of the inlet throat section. Furthermore, the bay is subjected to a very high anthropic pressure, mainly related to oyster farming. Thus, both natural and human-related processes seem relevant to explain high sedimentation rates. Current measurements, hydrodynamic modelling and cross-sectional area of the inlet throat are used in order to quantify tidal prism changes since 1824. Both flood and ebb tidal prism decreased by 35%. Decrease in the Marennes-Oléron Bay water volume is inferred to be responsible for a part of tidal prism decrease at the inlet. Tidal prisms decrease may also be explained by an increase in frictional resistance to tidal wave propagation, due to a general shoaling and oyster farms in the bay. A conceptual model is proposed, taking into account natural and human-related sedimentation processes, and explaining tidal inlet response to tidal bay evolutions.
Gait analysis in demented subjects: Interests and perspectives
Beauchet, Olivier; Allali, Gilles; Berrut, Gilles; Hommet, Caroline; Dubost, Véronique; Assal, Frédéric
2008-01-01
Gait disorders are more prevalent in dementia than in normal aging and are related to the severity of cognitive decline. Dementia-related gait changes (DRGC) mainly include decrease in walking speed provoked by a decrease in stride length and an increase in support phase. More recently, dual-task related changes in gait were found in Alzheimer’s disease (AD) and non-Alzheimer dementia, even at an early stage. An increase in stride-to-stride variability while usual walking and dual-tasking has been shown to be more specific and sensitive than any change in mean value in subjects with dementia. Those data show that DRGC are not only associated to motor disorders but also to problem with central processing of information and highlight that dysfunction of temporal and frontal lobe may in part explain gait impairment among demented subjects. Gait assessment, and more particularly dual-task analysis, is therefore crucial in early diagnosis of dementia and/or related syndromes in the elderly. Moreover, dual-task disturbances could be a specific marker of falling at a pre-dementia stage. PMID:18728766
Effect of climatological factors on respiratory syncytial virus epidemics
NOYOLA, D. E.; MANDEVILLE, P. B.
2008-01-01
SUMMARY Respiratory syncytial virus (RSV) presents as yearly epidemics in temperate climates. We analysed the association of atmospheric conditions to RSV epidemics in San Luis Potosí, S.L.P., Mexico. The weekly number of RSV detections between October 2002 and May 2006 were correlated to ambient temperature, barometric pressure, relative humidity, vapour tension, dew point, precipitation, and hours of light using time-series and regression analyses. Of the variation in RSV cases, 49·8% was explained by the study variables. Of the explained variation in RSV cases, 32·5% was explained by the study week and 17·3% was explained by meteorological variables (average daily temperature, maximum daily temperature, temperature at 08:00 hours, and relative humidity at 08:00 hours). We concluded that atmospheric conditions, particularly temperature, partly explain the year to year variability in RSV activity. Identification of additional factors that affect RSV seasonality may help develop a model to predict the onset of RSV epidemics. PMID:18177520
Personality Traits and Training Initiation Process: Intention, Planning, and Action Initiation
Laguna, Mariola; Purc, Ewelina
2016-01-01
The article aims at investigating the role of personality traits in relation to training initiation. Training initiation is conceptualized as a goal realization process, and explained using goal theories. There are three stages of the process analyzed: intention to undertake training, plan formulation, and actual training undertaking. Two studies tested the relationships between five personality traits, defined according to the five factor model, and the stages of the goal realization process. In Study 1, which explains training intention and training plans’ formulation, 155 employees participated. In Study 2, which was time-lagged with two measurement points, and which explains intention, plans, and training actions undertaken, the data from 176 employees was collected at 3 month intervals. The results of these studies show that personality traits, mainly openness to experience, predict the training initiation process to some degree: intention, plans, and actual action initiation. The findings allow us to provide recommendations for practitioners responsible for human resource development. The assessment of openness to experience in employees helps predict their motivation to participate in training activities. To increase training motivation it is vital to strengthen intentions to undertake training, and to encourage training action planning. PMID:27909414
Whitney, Paul; Hinson, John M; Satterfield, Brieann C; Grant, Devon A; Honn, Kimberly A; Van Dongen, Hans P A
2017-11-22
Insufficient sleep is a global public health problem resulting in catastrophic accidents, increased mortality, and hundreds of billions of dollars in lost productivity. Yet the effect of sleep deprivation (SD) on decision making and performance is often underestimated by fatigued individuals and is only beginning to be understood by scientists. The deleterious impact of SD is frequently attributed to lapses in vigilant attention, but this account fails to explain many SD-related problems, such as loss of situational awareness and perseveration. Using a laboratory study protocol, we show that SD individuals can maintain information in the focus of attention and anticipate likely correct responses, but their use of such a top-down attentional strategy is less effective at preventing errors caused by competing responses. Moreover, when the task environment requires flexibility, performance under SD suffers dramatically. The impairment in flexible shifting of attentional control we observed is distinct from lapses in vigilant attention, as corroborated by the specificity of the influence of a genetic biomarker, the dopaminergic polymorphism DRD2 C957T. Reduced effectiveness of top-down attentional control under SD, especially when conditions require flexibility, helps to explain maladaptive performance that is not readily explained by lapses in vigilant attention.
Personality Traits and Training Initiation Process: Intention, Planning, and Action Initiation.
Laguna, Mariola; Purc, Ewelina
2016-01-01
The article aims at investigating the role of personality traits in relation to training initiation. Training initiation is conceptualized as a goal realization process, and explained using goal theories. There are three stages of the process analyzed: intention to undertake training, plan formulation, and actual training undertaking. Two studies tested the relationships between five personality traits, defined according to the five factor model, and the stages of the goal realization process. In Study 1, which explains training intention and training plans' formulation, 155 employees participated. In Study 2, which was time-lagged with two measurement points, and which explains intention, plans, and training actions undertaken, the data from 176 employees was collected at 3 month intervals. The results of these studies show that personality traits, mainly openness to experience, predict the training initiation process to some degree: intention, plans, and actual action initiation. The findings allow us to provide recommendations for practitioners responsible for human resource development. The assessment of openness to experience in employees helps predict their motivation to participate in training activities. To increase training motivation it is vital to strengthen intentions to undertake training, and to encourage training action planning.
Cortese, C G; Ghislieri, Chiara; Colombo, Lara
2008-01-01
Organization research has shown increasing interest in the dynamics of work-family conflict (w.f.c.). The NEXT study highlights that w.f.c. significantly influences satisfaction for one's job and the decision to quit the nursing profession. This study analyzes w.f.c. in a sample of Italian nurses, with the aim of examining the main differences in relation to personal variables, and understanding the degree to which w.f.c. explains job satisfaction. A self-reporting questionnaire was administered to 325 nurses in different hospitals of Northern Italy. Descriptive, reliability and Anova data analysis was performed. The relationships between variables were analyzed through correlations (Pearson's r); the role of w.f.c. in explaining job satisfaction was estimated via multiple regression. W.f.c. appeared to be more critical in subjects who had care responsibilities and in those who had more demanding work assignments. W.f.c. contributed to explaining job satisfaction, even if it was not its principal determining factor. This area of research appears to be important in that it leads to a better comprehension of the dynamics involved in work satisfaction and can suggest possible initiatives for support and development.
Psychological correlates of loneliness in the older adult.
Walton, C G; Shultz, C M; Beck, C M; Walls, R C
1991-06-01
Loneliness is the emotional response to the discrepancy between desired and available relationships. As people grow old, the likelihood of experiencing age-related losses increases. Such losses may impede the maintenance or acquisition of desired relationships, resulting in a higher incidence of loneliness. This pilot study examines how loneliness relates to age-related losses, hopelessness, self-transcendence, and spiritual well-being in a convenience sample of 107 adults aged 65 years or older. The collective utility of the independent variables in predicting loneliness was investigated by means of a regression decision tree with an automatic random subset crossvalidation procedure. This procedure explained 46% of the variance. Higher scores for age-related losses and hopelessness were associated with higher loneliness scores. Higher scores for self-transcendence and existential spiritual well-being were associated with lower loneliness scores.
A change in competitive context reverses sexual selection on male size.
Kasumovic, M M; Andrade, M C B
2009-02-01
In studies of sexual selection, larger size is often argued to increase male fitness, and relatively smaller males are explained by genetic and/or environmental variation. We demonstrate that a size-development life-history trade-off could underlie the maintenance of a broad, unimodal distribution of size in male redback spiders (Latrodectus hasselti). Larger males are superior in direct competition, but redback males mature rapidly at small size in the presence of females. In field enclosures, we simulated two competitive contexts favouring development of divergent male sizes. Relatively smaller males lost when competing directly, but had 10 times higher fitness than relatively larger males when given the temporal advantage of rapid development. Linear selection gradients confirmed the reversal of selection on size, showing that it is critical to consider life-history decisions underlying the development of traits related to fitness.
Anomalous low strain induced by surface charge in nanoporous gold with low relative density.
Liu, Feng; Ye, Xing-Long; Jin, Hai-Jun
2017-07-26
The surface stress induced axial strain in a fiber-like solid is larger than its radical strain, and is also greater than the radical strain in similar-sized spherical solids. It is thus envisaged that the surface-induced macroscopic dimension change (i.e., actuation strain) in nanoporous gold (NPG) increases with decreasing relative density, or alternatively, with an increasing ratio between volumes of fiber-like ligaments and sphere-like nodes. In this study, electrochemical actuations of NPG with similar structure sizes, same (oxide-covered) surface state but different relative densities were characterized in situ in response to surface charging/discharging. We found that the actuation strain amplitude did not increase, but decreased dramatically with decreasing relative density of NPG, in contrast to the above prediction. The actuation strain decreased abruptly when the relative density of NPG was decreased to below 0.25, when the Au content in the AuAg precursor was below 20 at%. Further studies indicate that this anomalous behavior cannot be explained by potential- or size-dependences of the elasticity, the structure difference arising from different dealloying rates, or additional strain induced by the external load during dilatometry experiments. In NPG with low relative density, mutual movements of nano-ligaments may occur in the pore space and disconnected regions, which may compensate the local strain in ligaments and account for the anomalous low actuation strain in macroscopic NPG samples.
Martin, T.E.; Bassar, R.D.; Bassar, S.K.; Fontaine, J.J.; Lloyd, P.; Mathewson, Heather A.; Niklison, Alina M.; Chalfoun, A.
2006-01-01
Broad geographic patterns in egg and clutch mass are poorly described, and potential causes of variation remain largely unexamined. We describe interspecific variation in avian egg and clutch mass within and among diverse geographic regions and explore hypotheses related to allometry, clutch size, nest predation, adult mortality, and parental care as correlates and possible explanations of variation. We studied 74 species of Passeriformes at four latitudes on three continents: the north temperate United States, tropical Venezuela, subtropical Argentina, and south temperate South Africa. Egg and clutch mass increased with adult body mass in all locations, but differed among locations for the same body mass, demonstrating that egg and clutch mass have evolved to some extent independent of body mass among regions. A major portion of egg mass variation was explained by an inverse relationship with clutch size within and among regions, as predicted by life-history theory. However, clutch size did not explain all geographic differences in egg mass; eggs were smallest in South Africa despite small clutch sizes. These small eggs might be explained by high nest predation rates in South Africa; life-history theory predicts reduced reproductive effort under high risk of offspring mortality. This prediction was supported for clutch mass, which was inversely related to nest predation but not for egg mass. Nevertheless, clutch mass variation was not fully explained by nest predation, possibly reflecting interacting effects of adult mortality. Tests of the possible effects of nest predation on egg mass were compromised by limited power and by counterposing direct and indirect effects. Finally, components of parental investment, defined as effort per offspring, might be expected to positively coevolve. Indeed, egg mass, but not clutch mass, was greater in species that shared incubation by males and females compared with species in which only females incubate eggs. However, egg and clutch mass were not related to effort of parental care as measured by incubation attentiveness. Ecological and life-history correlates of egg and clutch mass variation found here follow from theory, but possible evolutionary causes deserve further study. ?? 2006 The Society for the Study of Evolution. All rights reserved.
ERIC Educational Resources Information Center
King, Chris; Kennett, Peter
2002-01-01
Explains how physics teaching can be more relevant for elementary and secondary students by integrating physics and earth science content that students can relate to and understand. Identifies and explains Earth contexts that can be appropriately implemented into the physics curriculum such as energy resources and radioactivity. (Author/YDS)
ERIC Educational Resources Information Center
Uitto, Anna
2014-01-01
The aim of the study was to discover the contribution of students' interest in school biology, as well as their self-efficacy and attitudes towards different science subjects and mathematics when explaining students' orientation towards biology-related careers at upper-secondary school. The data of 321 K-11 students (49% women) were…
ERIC Educational Resources Information Center
Floyd, Randy G.; McGrew, Kevin S.; Evans, Jeffrey J.
2008-01-01
This study examined the relative contributions of measures of Cattell-Horn-Carroll (CHC) cognitive abilities in explaining writing achievement. Drawing from samples that covered the age range of 7 to 18 years, simultaneous multiple regression was used to regress scores from the Woodcock-Johnson III (WJ III; Woodcock, McGrew, & Mather, 2001) that…
Introduction to ergonomics for healthcare workers.
Waters, Thomas R
2010-01-01
Healthcare workers who handle and move patients as part of their jobs suffer a disproportionately high number of work-related musculoskeletal disorders (MSDs). The majority of reported work-related MSDs are back pain cases that result in significant numbers of lost work days. It is likely that these lost workdays have a substantial impact on the quality and cost of health care. Patient care ergonomics can reduce the risk of work-related MSDs by helping safety experts design the work so it can be safely performed by most workers. This article provides a general overview of ergonomics--what it is, how it can be used to help design safe work, and why all healthcare workers and administrators should know and understand how excessive work demands can lead to increased risk of work-related MSDs. The article will also explain technological solutions that can be implemented to reduce the risk of work-related MSDs for healthcare workers.
The Cultural Boundaries of Perspective-Taking: When and Why Perspective-Taking Reduces Stereotyping.
Wang, Cynthia S; Lee, Margaret; Ku, Gillian; Leung, Angela K-Y
2018-06-01
Research conducted in Western cultures indicates that perspective-taking is an effective social strategy for reducing stereotyping. The current article explores whether and why the effects of perspective-taking on stereotyping differ across cultures. Studies 1 and 2 established that perspective-taking reduces stereotyping in Western but not in East Asian cultures. Using a socioecological framework, Studies 2 and 3 found that relational mobility, that is, the extent to which individuals' social environments provide them opportunities to choose new relationships and terminate old ones, explained our effect: Perspective-taking was negatively associated with stereotyping in relationally mobile (Western) but not in relationally stable (East Asian) environments. Finally, Study 4 examined the proximal psychological mechanism underlying the socioecological effect: Individuals in relationally mobile environments are more motivated to develop new relationships than those in relationally stable environments. Subsequently, when this motivation is high, perspective-taking increases self-target group overlap, which then decreases stereotyping.
Rousseaux, Marc; Braem, Bérenger; Honoré, Jacques; Saj, Arnaud
2015-08-01
Brain hemisphere lesions often cause a contralesional tilt of the subjective vertical (SV) a phenomenon related to spatial neglect and postural disorders. Depending on the method employed, different perceptual systems come into play when this gravitational vertical is assessed. Here, we compared the anatomical and psychophysical characteristics of modality-dependent SV biases in patients with right hemisphere stroke. The SV was measured with visual, haptic and visual-haptic modalities (SV, SVV, SVHV) in 46 patients with a relatively recent stroke. Voxel-based lesion-symptom mapping (performed with NPM(®)) was used to highlight brain areas in which lesions best explained the severity of task biases (p < .05). Lesions explaining the SVV tilt (TSVV) were centered on the posterior part of the middle temporal gyrus, those explaining the TSHV were more limited and anterior, without convergence with the former. Lesions explaining the TSVHV were centered on the superior temporal gyrus and more anterior those explaining the TSVV, with convergence with lesions explaining both the TSVV and the TSHV. Patients showed counterclockwise deviations in the SVs. Constant and variable errors were greater for the SHV than for the SVV and for the SVHV. The TSVV and TVHV were closely related to the presence of left spatial neglect and hemianopia. Errors in the SVV and (at a lesser degree) SVHV were preferentially related to lesions in visual associative cortex. The SVV and especially the SVHV provide valuable estimates of patient difficulties, in view of the lower associated variable errors (i.e., greater precision) and closer relationships with clinical disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.
2018-01-01
Abstract Dopamine has been suggested to be crucially involved in effort-related choices. Key findings are that dopamine depletion (i) changed preference for a high-cost, large-reward option to a low-cost, small-reward option, (ii) but not when the large-reward option was also low-cost or the small-reward option gave no reward, (iii) while increasing the latency in all the cases but only transiently, and (iv) that antagonism of either dopamine D1 or D2 receptors also specifically impaired selection of the high-cost, large-reward option. The underlying neural circuit mechanisms remain unclear. Here we show that findings i–iii can be explained by the dopaminergic representation of temporal-difference reward-prediction error (TD-RPE), whose mechanisms have now become clarified, if (1) the synaptic strengths storing the values of actions mildly decay in time and (2) the obtained-reward-representing excitatory input to dopamine neurons increases after dopamine depletion. The former is potentially caused by background neural activity–induced weak synaptic plasticity, and the latter is assumed to occur through post-depletion increase of neural activity in the pedunculopontine nucleus, where neurons representing obtained reward exist and presumably send excitatory projections to dopamine neurons. We further show that finding iv, which is nontrivial given the suggested distinct functions of the D1 and D2 corticostriatal pathways, can also be explained if we additionally assume a proposed mechanism of TD-RPE calculation, in which the D1 and D2 pathways encode the values of actions with a temporal difference. These results suggest a possible circuit mechanism for the involvements of dopamine in effort-related choices and, simultaneously, provide implications for the mechanisms of TD-RPE calculation. PMID:29468191
Artieri, Carlo G; Haerty, Wilfried; Gupta, Bhagwati P; Singh, Rama S
2008-05-01
Several hypotheses have been proposed to explain the persistence of dioecy despite the reproductive advantages conferred to hermaphrodites, including greater efficiency at purging deleterious mutations in the former. Dioecy can benefit from both mutation purging and accelerated evolution by bringing together beneficial mutations in the same individual via recombination and shuffling of genotypes. In addition, mathematical treatment has shown that sexual selection is also capable of mitigating the cost of maintaining separate sexes by increasing the overall fitness of sexual populations, and genomic comparisons have shown that sexual selection can lead to accelerated evolution. Here, we examine the advantages of dioecy versus hermaphroditism by comparing the rate of evolution in sex-related genes and the rate of accumulation of deleterious mutations using a large number of orthologs (11,493) in the dioecious Caenorhabditis remanei and the hermaphroditic Caenorhabditis briggsae. We have used this data set to estimate the deleterious mutation rate per generation, U, in both species and find that although it is significantly higher in hermaphrodites, both species are at least 2 orders of magnitude lower than the value required to explain the persistence of sex by efficiency at purging deleterious mutations alone. We also find that genes expressed in sperm are evolving rapidly in both species; however, they show a greater increase in their rate of evolution relative to genes expressed in other tissues in C. remanei, suggesting stronger sexual selection pressure acting on these genes in dioecious species. Interestingly, the persistence of a signal of rapid evolution of sperm genes in C. briggsae suggests a recent evolutionary origin of hermaphrodism in this lineage. Our results provide empirical evidence of increased sexual selection pressure in dioecious animals, supporting the possibility that sexual selection may play an important role in the maintenance of sexual reproduction.
Charlier, Caroline; Van Hoof, Elke; Pauwels, Evelyn; Lechner, Lilian; Spittaels, Heleen; De Bourdeaudhuij, Ilse
2013-01-01
Physical activity determinants are subject to change when confronted with the diagnosis of 'cancer' and new cancer-related determinants appear. The aim of the present study is to compare the contribution of cancer-related determinants with more general ones in explaining physical activity 3 weeks to 6 months post-treatment. A theory-based and validated questionnaire was used to identify physical activity levels (total and domain-specific) and associated determinants among 464 breast cancer survivors (aged 18 to 65 years) 3 weeks to 6 months post-treatment. Descriptive analyses showed higher scores for general determinants in comparison with cancer-related determinants. Nevertheless, regression analyses showed that both general and cancer-related determinants explained total and domain-specific physical activity. Self-efficacy, enjoyment, social support, lack of time and lack of company were important general determinants. The perception of returning to normal life, cancer-related barriers (fatigue, lack of energy and physical side effects) and self-efficacy in overcoming these barriers were important cancer-related determinants. Although results differed according to the women's working status and the physical activity domain, general self-efficacy explained most physical activity types in both groups. Comparable with the general population, enhancing breast cancer survivors' self-efficacy in being sufficiently physically active seems to be important in physical activity interventions post-treatment. However, interventions should be tailored to the experienced symptoms and working status of the women. Copyright © 2011 John Wiley & Sons, Ltd.
Skalická, Věra; Ringdal, Kristen; Witvliet, Margot I.
2015-01-01
Background Socioeconomic inequalities in mortality can be explained by different groups of risk factors. However, little is known whether repeated measurement of risk factors can provide better explanation of socioeconomic inequalities in health. Our study examines the extent to which relative educational and income inequalities in mortality might be explained by explanatory risk factors (behavioral, psychosocial, biomedical risk factors and employment) measured at two points in time, as compared to one measurement at baseline. Methods and Findings From the Norwegian total county population-based HUNT Study (years 1984–86 and 1995–1997, respectively) 61 513 men and women aged 25–80 (82.5% of all enrolled) were followed-up for mortality in 25 years until 2009, employing a discrete time survival analysis. Socioeconomic inequalities in mortality were observed. As compared to their highest socioeconomic counterparts, the lowest educated men had an OR (odds ratio) of 1.41 (95% CI 1.29–1.55) and for the lowest income quartile OR = 1.59 (1.48–1.571), for women OR = 1.35 (1.17–1.55), and OR = 1.40 (1.28–1.52), respectively. Baseline explanatory variables attenuated the association between education and income with mortality by 54% and 54% in men, respectively, and by 69% and 18% in women. After entering time-varying variables, this attainment increased to 63% and 59% in men, respectively, and to 25% (income) in women, with no improvement in regard to education in women. Change in biomedical factors and employment did not amend the explanation. Conclusions Addition of a second measurement for risk factors provided only a modest improvement in explaining educational and income inequalities in mortality in Norwegian men and women. Accounting for change in behavior provided the largest improvement in explained inequalities in mortality for both men and women, as compared to measurement at baseline. Psychosocial factors explained the largest share of income inequalities in mortality for men, but repeated measurement of these factors contributed only to modest improvement in explanation. Further comparative research on the relative importance of explanatory pathways assessed over time is needed. PMID:25853571
Skalická, Věra; Ringdal, Kristen; Witvliet, Margot I
2015-01-01
Socioeconomic inequalities in mortality can be explained by different groups of risk factors. However, little is known whether repeated measurement of risk factors can provide better explanation of socioeconomic inequalities in health. Our study examines the extent to which relative educational and income inequalities in mortality might be explained by explanatory risk factors (behavioral, psychosocial, biomedical risk factors and employment) measured at two points in time, as compared to one measurement at baseline. From the Norwegian total county population-based HUNT Study (years 1984-86 and 1995-1997, respectively) 61 513 men and women aged 25-80 (82.5% of all enrolled) were followed-up for mortality in 25 years until 2009, employing a discrete time survival analysis. Socioeconomic inequalities in mortality were observed. As compared to their highest socioeconomic counterparts, the lowest educated men had an OR (odds ratio) of 1.41 (95% CI 1.29-1.55) and for the lowest income quartile OR = 1.59 (1.48-1.571), for women OR = 1.35 (1.17-1.55), and OR = 1.40 (1.28-1.52), respectively. Baseline explanatory variables attenuated the association between education and income with mortality by 54% and 54% in men, respectively, and by 69% and 18% in women. After entering time-varying variables, this attainment increased to 63% and 59% in men, respectively, and to 25% (income) in women, with no improvement in regard to education in women. Change in biomedical factors and employment did not amend the explanation. Addition of a second measurement for risk factors provided only a modest improvement in explaining educational and income inequalities in mortality in Norwegian men and women. Accounting for change in behavior provided the largest improvement in explained inequalities in mortality for both men and women, as compared to measurement at baseline. Psychosocial factors explained the largest share of income inequalities in mortality for men, but repeated measurement of these factors contributed only to modest improvement in explanation. Further comparative research on the relative importance of explanatory pathways assessed over time is needed.
Sahadevan, S; Earnest, A; Koh, Y L; Lee, K M; Soh, C H; Ding, Y Y
2004-09-01
This study first aimed to determine the adequacy of the Diagnosis Related Grouping (DRG) model's ability to explain (1) the variance in the actual length of stay (LOS) of elderly medical inpatients and (2) the LOS difference in the same cohort between the departments of Geriatric Medicine (GRM) and General Medicine (GM). We then looked at how these explanatory abilities of the DRG changed when patients' function-linked variables (ignored by DRG) were incorporated into the model. Basic demographic data of a consecutively hospitalised cohort of elderly medical inpatients from GRM and GM, as well as their actual LOS, discharge DRG codes [with their corresponding trimmed average length of stay (ALOS)] and selected function-linked variables (including premorbid functional status, change in functional profile during hospitalisation and number of therapists seen) were recorded. Beginning with ALOS, function-linked variables that were significantly associated with LOS were then added into two multiple liner regression models so as to quantify how the functional dimension improved the DRGs' abilities to explain LOS variances and interdepartmental LOS differences. Forward selection procedure was employed to determine the final models. For the interdepartmental analysis, the study sample was restricted to patients who shared common DRG codes. 114 GRM and 118 GM patients were studied. Trimmed ALOS alone explained 8% of the actual LOS variance. With the addition of function-linked variables, the adjusted R2 of the final model increased to 28%. Due to common code restrictions, the data of 79 GRM and 78 GM patients were available for the analysis of interdepartmental LOS differences. At the unadjusted stage, the median stay of GRM patients was 4.3 days longer than GM's and with adjustments made for the DRGs, this difference was reduced to 3.9 days. Additionally adjusting for the patients' functional features diminished the interdepartmental LOS discrepancy even further, to 2.1 days. This study demonstrates that for elderly medical inpatients, the incorporation of patients' functional status significantly improves the DRG model's ability to predict the patients' actual LOS as well as to explain interdepartmental LOS differences between GRM and GM.
Eggert, Thomas; Straube, Andreas
2016-01-01
This study investigates the inter-trial variability of saccade trajectories observed in five rhesus macaques (Macaca mulatta). For each time point during a saccade, the inter-trial variance of eye position and its covariance with eye end position were evaluated. Data were modeled by a superposition of three noise components due to 1) planning noise, 2) signal-dependent motor noise, and 3) signal-dependent premotor noise entering within an internal feedback loop. Both planning noise and signal-dependent motor noise (together called accumulating noise) predict a simple S-shaped variance increase during saccades, which was not sufficient to explain the data. Adding noise within an internal feedback loop enabled the model to mimic variance/covariance structure in each monkey, and to estimate the noise amplitudes and the feedback gain. Feedback noise had little effect on end point noise, which was dominated by accumulating noise. This analysis was further extended to saccades executed during inactivation of the caudal fastigial nucleus (cFN) on one side of the cerebellum. Saccades ipsiversive to an inactivated cFN showed more end point variance than did normal saccades. During cFN inactivation, eye position during saccades was statistically more strongly coupled to eye position at saccade end. The proposed model could fit the variance/covariance structure of ipsiversive and contraversive saccades. Inactivation effects on saccade noise are explained by a decrease of the feedback gain and an increase of planning and/or signal-dependent motor noise. The decrease of the fitted feedback gain is consistent with previous studies suggesting a role for the cerebellum in an internal feedback mechanism. Increased end point variance did not result from impaired feedback but from the increase of accumulating noise. The effects of cFN inactivation on saccade noise indicate that the effects of cFN inactivation cannot be explained entirely with the cFN’s direct connections to the saccade-related premotor centers in the brainstem. PMID:27351741
Kristensen, Petter; Keyes, Katherine M; Susser, Ezra; Corbett, Karina; Mehlum, Ingrid Sivesind; Irgens, Lorentz M
2017-01-01
Perinatal mortality according to birth weight has an inverse J-pattern. Our aim was to estimate the influence of familial factors on this pattern, applying a cohort sibling design. We focused on excess mortality among macrosomic infants (>2 SD above the mean) and hypothesized that the birth weight-mortality association could be explained by confounding shared family factors. We also estimated how the participant's deviation from mean sibling birth weight influenced the association. We included 1 925 929 singletons, born term or post-term to mothers with more than one delivery 1967-2011 registered in the Medical Birth Registry of Norway. We examined z-score birth weight and perinatal mortality in random-effects and sibling fixed-effects logistic regression models including measured confounders (e.g. maternal diabetes) as well as unmeasured shared family confounders (through fixed effects models). Birth weight-specific mortality showed an inverse J-pattern, being lowest (2.0 per 1000) at reference weight (z-score +1 to +2) and increasing for higher weights. Mortality in the highest weight category was 15-fold higher than reference. This pattern changed little in multivariable models. Deviance from mean sibling birth weight modified the mortality pattern across the birth weight spectrum: small and medium-sized infants had increased mortality when being smaller than their siblings, and large-sized infants had an increased risk when outweighing their siblings. Maternal diabetes and birth weight acted in a synergistic fashion with mortality among macrosomic infants in diabetic pregnancies in excess of what would be expected for additive effects. The inverse J-pattern between birth weight and mortality is not explained by measured confounders or unmeasured shared family factors. Infants are at particularly high mortality risk when their birth weight deviates substantially from their siblings. Sensitivity analysis suggests that characteristics related to maternal diabetes could be important in explaining the increased mortality among macrosomic infants.
A study into psychosocial factors as predictors of work-related fatigue.
Rahman, Hanif Abdul; Abdul-Mumin, Khadizah; Naing, Lin
2016-07-14
To explore and determine relationship between psychosocial factors and work-related fatigue among emergency and critical care nurses in Brunei. Cross-sectional study conducted on all emergency and critical care nurses across Brunei public hospitals from February to April 2016. 201 nurses participated in the study (82% response rate). A total of 36% of the variance of chronic fatigue was explained by stress, trust in management, decision latitude, self-rated health, and work-family conflict. Burnout, self-rated health, commitment to workplace, and trust in management explained 30% of the variance of acute fatigue. Stress, work-family conflict and reward explained 28% of the variance of intershift recovery after controlling for significant sociodemographic variables. Smoking was identified as an important sociodemographic factor for work-related fatigue. Psychosocial factors were good predictors of work-related fatigue. A range of psychosocial factors were established, however more research is required to determine all possible causation factors of nurses' work-related fatigue.
Schiebener, Johannes; Brand, Matthias
2017-06-01
Previous literature has explained older individuals' disadvantageous decision-making under ambiguity in the Iowa Gambling Task (IGT) by reduced emotional warning signals preceding decisions. We argue that age-related reductions in IGT performance may also be explained by reductions in certain cognitive abilities (reasoning, executive functions). In 210 participants (18-86 years), we found that the age-related variance on IGT performance occurred only in the last 60 trials. The effect was mediated by cognitive abilities and their relation with decision-making performance under risk with explicit rules (Game of Dice Task). Thus, reductions in cognitive functions in older age may be associated with both a reduced ability to gain explicit insight into the rules of the ambiguous decision situation and with failure to choose the less risky options consequently after the rules have been understood explicitly. Previous literature may have underestimated the relevance of cognitive functions for age-related decline in decision-making performance under ambiguity.
Domestic and International Climate Migration from Rural Mexico
Nawrotzki, Raphael J.; Runfola, Daniel M.; Hunter, Lori M.; Riosmena, Fernando
2016-01-01
Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move. PMID:28439146
Kin competition within groups: the offspring depreciation hypothesis.
Ridley, J; Sutherland, W J
2002-01-01
Where relatives compete for the same resources (kin competition) and each obtains an equal share, this can favour the evolution of elevated dispersal rates, such that most resource competition is among non-relatives. We show that this effect evaporates as among-sibling dominance increases to the point where the allocation of resources is maximally unequal. We restore a kin-competition effect on emigration rates from dominance-ranked family groups by showing that where siblings form queues to inherit the breeding positions, the length of the queue affects the fitness of all individuals by depreciating the rank of subsequent offspring. Incorporating this 'offspring depreciation' effect decreases optimal queue lengths, increases dispersal rates and explains the otherwise paradoxical use of sinks by cooperatively breeding birds in stable environments. The offspring depreciation effect also favours the evolution of small, but consistent, clutch sizes and high reproductive skew, but constrains the evolution of alloparenting. PMID:12573070
A New Clinical Sign of Lumbrical Plus Finger.
Schuind, Frédéric A; Moungondo, Fabian; Van Wetter, Pierre
2018-06-01
Paradoxical finger extension is the classical clinical presentation of the lumbrical plus syndrome. We report a new additional sign, increased metacarpophalangeal flexion of the involved finger when the patient tries to make a fist. Three cases of lumbrical tightness are discussed, illustrating this new sign in 3 different clinical settings. The new sign was present in all 3 cases. Lumbrical tenotomy corrected the paradoxical interphalangeal extension and partly the increased metacarpophalangeal flexion. The lumbrical tendon has a relatively high moment arm relative to the metacarpophalangeal joint, which could explain the basis of this clinical sign. This new physical examination sign may help in diagnosing the lumbrical plus syndrome, a subtle complication of flexor digitorum profundus lesions that is not easily diagnosed but which is easily addressed. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Muftić, Lisa R
2006-12-01
Institutional anomie theory (IAT) contends that crime can be explained by an examination of American society, particularly the exaggerated emphasis on economic success inherent in American culture, which has created a "cheating orientation" that permeates structural institutions, including academia. Consistent with its macrosocial perspective, previous tests of IAT have examined IAT variables at the structural level only. The current study tests the robustness of IAT by operationalizing IAT variables at the individual level and looking at a minor form of deviance, student cheating. The author also examines the role statistical modeling has in testing the theory at the microlevel. Undergraduates, 122 American born and 48 international, were surveyed about their cheating behaviors and adherence to economic goal orientations. Results related to the hypothesis that American students, relative to foreign-born students, will have an increased adherence to economic goal orientations that increase cheating behaviors are presented, as are suggestions for future studies.
Creating lenticular galaxies with mergers
NASA Astrophysics Data System (ADS)
Querejeta, Miguel; Eliche-Moral, M. Carmen; Tapia, Trinidad; Borlaff, Alejandro; van de Ven, Glenn; Lyubenova, Mariya; Martig, Marie; Falcón-Barroso, Jesús; Méndez-Abreu, Jairo; Zamorano, Jaime; Gallego, Jesús
2017-03-01
Lenticular galaxies (S0s) represent the majority of early-type galaxies in the local Universe, but their formation channels are still poorly understood. While galaxy mergers are obvious pathways to suppress star formation and increase bulge sizes, the marked parallelism between spiral and lenticular galaxies (e.g. photometric bulge-disc coupling) seemed to rule out a potential merger origin. Here, we summarise our recent work in which we have shown, through N-body numerical simulations, that disc-dominated lenticulars can emerge from major mergers of spiral galaxies, in good agreement with observational photometric scaling relations. Moreover, we show that mergers simultaneously increase the light concentration and reduce the angular momentum relative to their spiral progenitors. This explains the mismatch in angular momentum and concentration between spirals and lenticulars recently revealed by CALIFA observations, which is hard to reconcile with simple fading mechanisms (e.g. ram-pressure stripping).
Breastfeeding promotion in Thailand.
Hangchaovanich, Yupayong; Voramongkol, Nipunporn
2006-10-01
National Breastfeeding Project in Thailand began in 1989. The main activities were the promotion of the Baby-Friendly Hospital Initiative; legislation on maternity leave; and the Code of Marketing of Breastmilk Substitutes and related products. The development of Baby - Friendly Hospital Initiative may in part explain the increasing of prevalence rate of breastfeeding. However exclusive breastfeeding has not shown favorable increases. The survey in 2005 found exclusive breastfeeding at 6 months was 14.5% while the national target of the Ninth National Health Development Plan (NHDP) has been set at 30%. There are many factors affecting the success of breastfeeding promotion. The Ministry of Public Health, which is responsible for infant/child health, has to find solutions with the most potential for any problem related to such a matter especially prevention of childhood diseases. Furthermore, it must also create an environment where good health fundamentals for physical and intellectual developments from infancy to childhood and maturity exist.
Kin competition within groups: the offspring depreciation hypothesis.
Ridley, J; Sutherland, W J
2002-12-22
Where relatives compete for the same resources (kin competition) and each obtains an equal share, this can favour the evolution of elevated dispersal rates, such that most resource competition is among non-relatives. We show that this effect evaporates as among-sibling dominance increases to the point where the allocation of resources is maximally unequal. We restore a kin-competition effect on emigration rates from dominance-ranked family groups by showing that where siblings form queues to inherit the breeding positions, the length of the queue affects the fitness of all individuals by depreciating the rank of subsequent offspring. Incorporating this 'offspring depreciation' effect decreases optimal queue lengths, increases dispersal rates and explains the otherwise paradoxical use of sinks by cooperatively breeding birds in stable environments. The offspring depreciation effect also favours the evolution of small, but consistent, clutch sizes and high reproductive skew, but constrains the evolution of alloparenting.
Migrant Networks and Pathways to Child Obesity in Mexico
CREIGHTON, MATHEW J; GOLDMAN, NOREEN; TERUEL, GRACIELA; RUBALCAVA, LUIS
2011-01-01
The purpose of this paper is twofold: 1) to assess the link between migrant networks and becoming overweight or obese and 2) to explore the pathways by which migrant networks may contribute to the increasing overweight and obese population of children in Mexico. Using two waves of the Mexican Family Life Survey (MxFLS), we find that children and adolescents (ages 3 to 15) living in households with migrant networks are at an increased risk of becoming overweight or obese over the period of observation, relative to their peers with no migrant networks. Sedentary behavior and household-level measures of economic wellbeing explain some of the association between networks and changes in weight status, but the role of extended networks remains significant. Community-level characteristics related to migration do not account for any of the observed relationship between household-level networks and becoming overweight or obese. PMID:21277058
Domestic and International Climate Migration from Rural Mexico.
Nawrotzki, Raphael J; Runfola, Daniel M; Hunter, Lori M; Riosmena, Fernando
2016-12-01
Evidence is increasing that climate change and variability may influence human migration patterns. However, there is less agreement regarding the type of migration streams most strongly impacted. This study tests whether climate change more strongly impacted international compared to domestic migration from rural Mexico during 1986-99. We employ eight temperature and precipitation-based climate change indices linked to detailed migration histories obtained from the Mexican Migration Project. Results from multilevel discrete-time event-history models challenge the assumption that climate-related migration will be predominantly short distance and domestic, but instead show that climate change more strongly impacted international moves from rural Mexico. The stronger climate impact on international migration may be explained by the self-insurance function of international migration, the presence of strong migrant networks, and climate-related changes in wage difference. While a warming in temperature increased international outmigration, higher levels of precipitation declined the odds of an international move.
Migrant networks and pathways to child obesity in Mexico.
Creighton, Mathew J; Goldman, Noreen; Teruel, Graciela; Rubalcava, Luis
2011-03-01
The purpose of this paper is twofold: 1) to assess the link between migrant networks and becoming overweight or obese and 2) to explore the pathways by which migrant networks may contribute to the increasing overweight and obese population of children in Mexico. Using two waves of the Mexican Family Life Survey (MxFLS), we find that children and adolescents (ages 3 to 15) living in households with migrant networks are at an increased risk of becoming overweight or obese over the period of observation, relative to their peers with no migrant networks. Sedentary behavior and household-level measures of economic wellbeing explain some of the association between networks and changes in weight status, but the role of extended networks remains significant. Community-level characteristics related to migration do not account for any of the observed relationship between household-level networks and becoming overweight or obese. Copyright © 2010 Elsevier Ltd. All rights reserved.
Pharmacogenetics of leptin in antipsychotic-associated weight gain and obesity-related complications
Lee, Amy K; Bishop, Jefrey R
2013-01-01
Second-generation antipsychotics can greatly improve symptoms of psychosis-spectrum disorders. Unfortunately, these drugs are associated with weight gain, which increases a patient’s risk for developing chronic diseases including Type 2 diabetes, cardiovascular diseases or other obesity-related complications. There are interindividual differences in weight gain resulting from antipsychotic drug use that may be explained by pharmacodynamic characteristics of these agents as well as clinical factors. In addition, genetic variations in pathways associated with satiety are increasingly recognized as potential contributors to antipsychotic-associated weight gain. Polymorphisms in the leptin gene, as well as the leptin receptor gene, are potential pharmacogenetic markers associated with these outcomes. This article summarizes evidence for the associations of the leptin gene and the leptin receptor gene polymorphisms with antipsychotic-induced weight gain, potential mechanisms underlying these relationships, and discusses areas for future pharmacogenetic investigation. PMID:21787190
Behie, A M; O'Donnell, M H
2017-09-20
Many industrialized nations are currently experiencing a decline in average secondary sex ratio (SSR) resulting in fewer boys being born relative to girls. While many potential factors may explain the decline in the birth of males relative to females, it seems most studies support the idea that male offspring are produced less often when environmental conditions are poor owing to males being more susceptible to loss in harsh environments. This study investigates the maternal factors that are associated with the sex of offspring in a cohort of the Australian population. It found that greater parental perceptions of wealth were significantly associated with an increase in the number of sons produced. These results suggest that male offspring are born at increased numbers to women with higher available resources, which may reflect the fact that male offspring are more vulnerable in poor environments.
[Atherosclerosis, oxidative stress and physical activity. Review].
Calderón, Juan Camilo; Fernández, Ana Zita; María de Jesús, Alina Isabel
2008-09-01
Atherosclerosis and related diseases have emerged as the leading cause of morbidity and mortality in the western world and, therefore, as a problem of public health. Free radicals and reactive oxygen species have been suggested to be part of the pathophysiology of these diseases. It is well known that physical activity plays an important role as a public health measure by reducing the risk of developing atherosclerosis-related cardiovascular events in the general population. It is also known that physical activity increases in some tissues, the reactive oxygen species production. In this review the atherosclerosis-oxidative stress-physical activity relationship is focused on the apparent paradox by which physical activity reduces atherosclerosis and cardiovascular risk in parallel with the activation of an apparently damaging mechanism which is an increased oxidative stress. A hypothesis including the experimental and clinical evidence is presented to explain the aforementioned paradox.
ERIC Educational Resources Information Center
Kunar, L. N. S.
1975-01-01
Describes the forces responsible for the eruptions of volcanoes and gives the physical and chemical parameters governing the type of eruption. Explains the structure of the earth in relation to volcanoes and explains the location of volcanic regions. (GS)
Periodic nonlinear waves resulting from the contact interaction of a crack
NASA Astrophysics Data System (ADS)
Lee, Sang Eon; Jin, Suyeong; Hong, Jung-Wuk
2017-09-01
When two different inputs of distinct low and high frequencies are applied to a medium, the linear responses are composed of waves of two dominant frequencies. However, microcracks such as fatigue cracks generate nonlinear waves by modulating the characteristics of the incident waves. Although this phenomenon has been observed and used to detect microcracks, the underlying principles have not been thoroughly elucidated. The hysteresis properties were introduced to describe the nonlinear relationship between the stress and strain to explain these phenomena [Van Den Abeele et al., Res. Nondestruct. Eval. 12, 17 (2000) and Nazarov et al., Acoust. Phys. 49, 344 (2003)]. The generation of harmonics was explained by superimposing stress-strain relations that vary with crack width and excitation magnitude. As the crack depth increases, the ratio of magnitudes of the second harmonic to the first harmonic increases, but the increment becomes smaller [Kawashima et al., Ultrasonics 40, 611 (2002)]. Here, we show that the waves affected by the contact motion of the crack surfaces cultivate the nonlinearity in waveforms, resulting in high frequency off-band signals. With the hypothesis that the clapping of cracks might generate nonlinear components close to the high excitation frequency, we prove that the generation of the high frequency off-band peaks is directly affected by the clapping contact interaction of the crack surfaces. The amount of energy transmitted is closely related to the size of the crack width and the magnitudes of low and high frequency excitations.
Yan, Hai; Fan, Shuxin; Guo, Chenxiao; Hu, Jie; Dong, Li
2014-01-01
The effects of land cover on urban-rural and intra-urban temperature differences have been extensively documented. However, few studies have quantitatively related air temperature to land cover composition at a local scale which may be useful to guide landscape planning and design. In this study, the quantitative relationships between air temperature and land cover composition at a neighborhood scale in Beijing were investigated through a field measurement campaign and statistical analysis. The results showed that the air temperature had a significant positive correlation with the coverage of man-made surfaces, but the degree of correlation varied among different times and seasons. The different land cover types had different effects on air temperature, and also had very different spatial extent dependence: with increasing buffer zone size (from 20 to 300 m in radius), the correlation coefficient of different land cover types varied differently, and their relative impacts also varied among different times and seasons. At noon in summer, ∼37% of the variations in temperature were explained by the percentage tree cover, while ∼87% of the variations in temperature were explained by the percentage of building area and the percentage tree cover on summer night. The results emphasize the key role of tree cover in attenuating urban air temperature during daytime and nighttime in summer, further highlighting that increasing vegetation cover could be one effective way to ameliorate the urban thermal environment. PMID:25010134
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prywer, Jolanta, E-mail: jolanta.prywer@p.lodz.pl; Olszynski, Marcin; Mielniczek-Brzóska, Ewa
2015-11-15
Effect of trisodium citrate on the precipitation of carbonate apatite is studied. The experimental series are performed in the solution of artificial urine. The investigations are related to infectious urinary stones formation as carbonate apatite is one of the main components of this kind of stones. To mimic a real infection in urinary tract the aqueous ammonia solution was added to the solution of artificial urine. The spectrophotometric results demonstrate that trisodium citrate increases induction time with respect to carbonate apatite formation and decreases the efficiency of carbonate apatite precipitation. The inhibitory effect of trisodium citrate on the precipitation ofmore » carbonate apatite is explained in base of chemical speciation analysis. Such an analysis demonstrates that the inhibitory effect is mainly related with the fact that trisodium citrate binds Ca{sup 2+} ions and causes the formation of CaCit{sup −} and Ca{sub 10}(PO{sub 4}){sub 6}CO{sub 3} complexes. Trisodium citrate binds Ca{sup 2+} ions in the range of pH from 6 to 9.5 for which carbonate apatite is favored to be formed. - Highlights: • Trisodium citrate (TC) increases induction time of carbonate apatite (CA) formation. • TC decreases the efficiency of CA precipitation. • The inhibitory effect of TC is explained in base of chemical speciation analysis. • The inhibitory effect is mainly related with the fact that TC binds Ca{sup 2+} ions. • TC binds Ca{sup 2+} ions in the range of pH from 6 to 9.5 for which CA is formed.« less
NASA Astrophysics Data System (ADS)
Kohl, L.; Philben, M. J.; Edwards, K. A.; Podrebarac, F. A.; Jamie, W.; Ziegler, S. E.
2017-12-01
Warmer climates have been associated with reduced soil organic matter (SOM) bioreactivity, lower respiration rates at a given temperature, which is typically attributed to the presence of more decomposed SOM. Cross site studies, however, indicate that ecosystem regime shifts associated with long-term climate warming can affect SOM properties through changes in vegetation and plant litter inputs to soils. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming remains poorly understood. To address this, we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids), and isotopic composition of plant litter and SOM across a well-constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. Climate effects on vascular plant litter chemistry explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer forests. These results indicate that a climate induced decrease in the proportion of moss inputs will not only impact SOM chemistry but also increase the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils.
Associations between Screen Time and Physical Activity among Spanish Adolescents
Serrano-Sanchez, Jose A.; Martí-Trujillo, Sara; Lera-Navarro, Angela; Dorado-García, Cecilia; González-Henríquez, Juan J.; Sanchís-Moysi, Joaquín
2011-01-01
Background Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. Methodology/Principal Findings A multi-stage stratified random sampling method was used to select 3503 adolescents (12–18 years old) from the school population of Gran Canaria, Spain. MVPA, screen-time in front of television, computer, video game console and portable console was assessed in the classroom by fulfilling a standardized questionnaire. Bivariate and multivariate logistic regression analyses adjusted by a set of social-environmental variables were carried out. Forty-six percent of girls (95% CI±2.3%) and 26% of boys (95% CI±2.1%) did not meet the MVPA recommendations for adolescents. Major gender differences were observed in the time devoted to vigorous PA, video games and the total time spent on screen-based activities. Boys who reported 4 hours•week−1 or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44–0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors. Conclusions/Significance No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity. PMID:21909435
Comparable Neutrophil Responses for Arm and Intensity-matched Leg Exercise.
Leicht, Christof A; Goosey-Tolfrey, Victoria L; Bishop, Nicolette C
2017-08-01
Arm exercise is performed at lower absolute intensities than lower body exercise. This may impact on intensity-dependent neutrophil responses, and it is unknown whether individuals restricted to arm exercise experience the same changes in the neutrophil response as found for lower body exercise. Therefore, we aimed to investigate the importance of exercise modality and relative exercise intensity on the neutrophil response. Twelve moderately trained men performed three 45-min constant load exercise trials after determination of peak oxygen uptake for arm exercise (V˙O2peak arms) and cycling (V˙O2peak legs): 1) arm cranking exercise at 60% V˙O2peak arms, 2) moderate cycling at 60% V˙O2peak legs, and 3) easy cycling at 60% V˙O2peak arms. Neutrophil numbers in the circulation increased for all exercise trials, but were significantly lower for easy cycling when compared with arm exercise (P = 0.009), mirroring the blunted increase in HR and epinephrine during easy cycling. For all trials, exercising HR explained some of the variation of the neutrophil number 2 h postexercise (R = 0.51-0.69), epinephrine explaining less of this variation (R = 0.21-0.34). The number of neutrophils expressing CXCR2 decreased in the recovery from exercise in all trials (P < 0.05). Arm and leg exercise elicits the same neutrophil response when performed at the same relative intensity, implying that populations restricted to arm exercise might achieve a similar exercise induced neutrophil response as those performing lower body exercise. A likely explanation for this is the higher sympathetic activation and cardiac output for arm and relative intensity-matched leg exercise when compared with easy cycling, which is partly reflected in HR. This study further shows that the downregulation of CXCR2 may be implicated in exercise-induced neutrophilia.
Riva-Murray, K.; Riemann, R.; Murdoch, P.; Fischer, J.M.; Brightbill, R.
2010-01-01
Widespread and increasing urbanization has resulted in the need to assess, monitor, and understand its effects on stream water quality. Identifying relations between stream ecological condition and urban intensity indicators such as impervious surface provides important, but insufficient information to effectively address planning and management needs in such areas. In this study we investigate those specific landscape metrics which are functionally linked to indicators of stream ecological condition, and in particular, identify those characteristics that exacerbate or mitigate changes in ecological condition over and above impervious surface. The approach used addresses challenges associated with redundancy of landscape metrics, and links landscape pattern and composition to an indicator of stream ecological condition across a broad area of the eastern United States. Macroinvertebrate samples were collected during 2000-2001 from forty-two sites in the Delaware River Basin, and landscape data of high spatial and thematic resolution were obtained from photointerpretation of 1999 imagery. An ordination-derived 'biotic score' was positively correlated with assemblage tolerance, and with urban-related chemical characteristics such as chloride concentration and an index of potential pesticide toxicity. Impervious surface explained 56% of the variation in biotic score, but the variation explained increased to as high as 83% with the incorporation of a second land use, cover, or configuration metric at catchment or riparian scales. These include land use class-specific cover metrics such as percent of urban land with tree cover, forest fragmentation metrics such as aggregation index, riparian metrics such as percent tree cover, and metrics related to urban aggregation. Study results indicate that these metrics will be important to monitor in urbanizing areas in addition to impervious surface. ?? 2010 US Government.
Pan-Tropical Analysis of Climate Effects on Seasonal Tree Growth
Wagner, Fabien; Rossi, Vivien; Aubry-Kientz, Mélaine; Bonal, Damien; Dalitz, Helmut; Gliniars, Robert; Stahl, Clément; Trabucco, Antonio; Hérault, Bruno
2014-01-01
Climate models predict a range of changes in tropical forest regions, including increased average temperatures, decreased total precipitation, reduced soil moisture and alterations in seasonal climate variations. These changes are directly related to the increase in anthropogenic greenhouse gas concentrations, primarily CO2. Assessing seasonal forest growth responses to climate is of utmost importance because woody tissues, produced by photosynthesis from atmospheric CO2, water and light, constitute the main component of carbon sequestration in the forest ecosystem. In this paper, we combine intra-annual tree growth measurements from published tree growth data and the corresponding monthly climate data for 25 pan-tropical forest sites. This meta-analysis is designed to find the shared climate drivers of tree growth and their relative importance across pan-tropical forests in order to improve carbon uptake models in a global change context. Tree growth reveals significant intra-annual seasonality at seasonally dry sites or in wet tropical forests. Of the overall variation in tree growth, 28.7% was explained by the site effect, i.e. the tree growth average per site. The best predictive model included four climate variables: precipitation, solar radiation (estimated with extrasolar radiation reaching the atmosphere), temperature amplitude and relative soil water content. This model explained more than 50% of the tree growth variations across tropical forests. Precipitation and solar radiation are the main seasonal drivers of tree growth, causing 19.8% and 16.3% of the tree growth variations. Both have a significant positive association with tree growth. These findings suggest that forest productivity due to tropical tree growth will be reduced in the future if climate extremes, such as droughts, become more frequent. PMID:24670981
Associations between screen time and physical activity among Spanish adolescents.
Serrano-Sanchez, Jose A; Martí-Trujillo, Sara; Lera-Navarro, Angela; Dorado-García, Cecilia; González-Henríquez, Juan J; Sanchís-Moysi, Joaquín
2011-01-01
Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. A multi-stage stratified random sampling method was used to select 3503 adolescents (12-18 years old) from the school population of Gran Canaria, Spain. MVPA, screen-time in front of television, computer, video game console and portable console was assessed in the classroom by fulfilling a standardized questionnaire. Bivariate and multivariate logistic regression analyses adjusted by a set of social-environmental variables were carried out. Forty-six percent of girls (95% CI±2.3%) and 26% of boys (95% CI±2.1%) did not meet the MVPA recommendations for adolescents. Major gender differences were observed in the time devoted to vigorous PA, video games and the total time spent on screen-based activities. Boys who reported 4 hours•week(-1) or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44-0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors. No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity.