This study aimed to determine how California secondary physical education teachers perceive the state mandated youth fitness testing for the 5th, 7th, and 9th grades using Fitnessgram. The ...participants were secondary school physical education teachers (N = 323). A previously validated attitudinal instrument (Keating & Silverman, 2004a) was used to collect the data. The means and standard deviations for each attitude subdomain and the overall attitudes were computed. MANOVA and ANOVA were employed to test the differences in attitudes by demographic and profession-related variables. Teachers' overall attitudes toward the Fitnessgram were slightly higher than a neutral attitude, indicating slightly positive attitudes on a 7-point Likert scale (M = 4.47, SD = 1.06). The mean scores for the attitude subdomain of cognitive (i.e., usefulness of fitness test results) and the affective (i.e., enjoyment of implementing fitness tests, and enjoyment of using fitness test results) components were 4.25 (SD = 1.38), 4.90 (SD = 1.15), and 4.39 (SD = 1.17), respectively. The data from the study suggested that teachers marginally agreed that the test results were useful and that they somewhat enjoyed implementing the test. Class size and student grade levels taught were important profession-related variables to consider regarding teacher attitudes toward the Fitnessgram.
Life-history theory allows predictions of how changes in environmental selection pressures along a species' geographic distribution result in discrete shifts in life-history traits. We tested for ...spatial patterns of 24 populations of brown bears Ursus arctos across North America that grouped according to the following environmental and population parameters: evapotranspiration as a correlate of primary productivity of vegetation, coefficient of variation of monthly evapotranspiration values as a measure of seasonality, population density, and adult female weight. Cluster analysis grouped brown bear populations into two regions: Pacific-coastal populations characterized by high population density and large females that lived in areas of high primary productivity and low seasonality, and inland and barren-ground populations characterized by relatively low density and small bears that lived in areas of low productivity and high seasonality. For each region, we tested whether life-history traits (age at maturity and interbirth interval) related to primary productivity or seasonality. High altitude (interior; > 1000 m) and high latitude (barren-ground; > 65°N) populations respond to extremes in seasonality with risk-spreading adaptations. For example, age at maturity and interbirth interval increased with greater seasonality. In contrast, Pacific-coastal populations living on the western edge of brown bear geographic range respond to intraspecific competition at high densities by maximizing offspring competitive ability. For example, age at maturity increased with greater primary productivity and high population density. In each region, the female parent decided on the life-history trade-offs required to reduce the risks of offspring mortality depending on the environmental pattern.
We investigate the degree of between-population genetic differentiation in the Mediterranean field cricket Gryllus bimaculatus, as well as the possible causes of such differentiation. Using ...cytochrome b mtDNA sequences, we estimate genetic variation in G. bimaculatus from seven South African and two Mediterranean populations. Within-population genetic variation in Europe (two haplotypes, one unique to a single individual) suggest low effective population size and strong bottlenecks with associated founder effects, probably due to cold winter environments in Europe that limit reproduction to a short part of the summer. The likely cause for this is the daily maxima in winter temperatures that fall below the critical level of 16°C (enabling normal calling and courtship behaviour) in Mediterranean Europe, whereas the equivalent temperatures in southern Africa are above this limit and enable reproduction over a large part of the year. European genetic variants were either shared with Africa or closely related to African haplotypes. For survival, European populations are probably dependent on immigration from other areas, including Africa. South African populations have low but measurable gene flow with Europe and show significant between-population genetic differentiation (30 haplotypes). Isolation-by-distance is not sufficient to explain the degree of between-population genetic differences observed, and a large degree of dispersal is also required in order to account for the observed patterns. Differences in morphology and calling behaviour among these populations are underlied by these genetic differences.
Globalisation involves geographically wider transaction networks and has multiple interrelated dimensions. The globalisation process has geographical scope, volume and density of transactions, and a ...direction and pace of change. Globalization has a long history, and the local and the global have almost continuously interacted. Most forward changes have been incremental, and there have also been major reversals or almost complete system-breakdowns. There are numerous drivers of globalization of different types, persons, and groups with varying motives, and anonymous drivers like technology, weather, and disease. The article devotes most attention to a review of selected patterns and trends in contemporary globalisation These are climate change; demographic trends, income inequality, and migration; security concerns, technology, and peacekeeping; competing ideologies; the global economy, equities, trade, banking reform, and tax havens; and shifting power relationships among the United States, Europe, China, Japan, and Emerging Markets.
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BFBNIB, DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Context. The reionization of the Universe is one of the most important topics of present-day astrophysical research. The most plausible candidates for the reionization process are star-forming ...galaxies, which according to the predictions of the majority of the theoretical and semi-analytical models should dominate the H I ionizing background at z greater than or similar to 3. Aims. We measure the Lyman continuum escape fraction, which is one of the key parameters used to compute the contribution of star-forming galaxies to the UV background. It provides the ratio between the photons produced at lambda <= 912 angstrom rest-frame and those that are able to reach the inter-galactic medium, i.e. that are not absorbed by the neutral hydrogen or by the dust of the galaxy's inter-stellar medium. Methods. We used ultra-deep U-band imaging (U = 30.2 mag at 1 sigma) from Large Binocular Camera at the Large Binocular Telescope (LBC/LBT) in the CANDELS/GOODS-North field and deep imaging in the COSMOS and EGS fields in order to estimate the Lyman continuum escape fraction of 69 star-forming galaxies with secure spectroscopic redshifts at 3.27 <= z <= 3.40 to faint magnitude limits (L = 0.2L*, or equivalently M-1500 similar to -19). The narrow redshift range implies that the LBC U-band filter exclusively samples the lambda <= 912 angstrom rest-frame wavelengths. Results. We measured through stacks a stringent upper limit (<1.7% at 1 sigma) for the relative escape fraction of H I ionizing photons from bright galaxies (L > L*), while for the faint population (L = 0.2L*) the limit to the escape fraction is less than or similar to 10%. We computed the contribution of star-forming galaxies to the observed UV background at z similar to 3 and find that it is not sufficient to keep the Universe ionized at these redshifts unless their escape fraction increases significantly (>= 10%) at low luminosities (M-1500 >= -19). Conclusions. We compare our results on the Lyman continuum escape fraction of high-z galaxies with recent estimates in the literature, and discuss future prospects to shed light on the end of the Dark Ages. In the future, strong gravitational lensing will be fundamental in order to measure the Lyman continuum escape fraction down to faint magnitudes (M-1500 similar to -16) that are inaccessible with the present instrumentation on blank fields. These results will be important in order to quantify the role of faint galaxies to the reionization budget.
This study examined cutaneous vasoconstriction to whole-body hypothermia, specifically contributions of neural and endothelial vasomotor responses in glabrous and non-glabrous skin. Eleven ...participants were semi-recumbent at an ambient temperature of 22 °C for 30 min, after which ambient temperature was decreased to 0 °C until rectal temperature (Tre) had decreased by 0.5 °C. Laser-Doppler fluxmetry was measured at the forehead and thigh for measures of glabrous and non-glabrous skin, respectively; wavelet analysis was performed on the laser-Doppler signal to determine endothelial and neural activities. Hypothermia took on average 97 ± 7 min and caused marked decreases at glabrous (42 ± 5%baseline, p < 0.001) and non-glabrous (69 ± 4%baseline, p < 0.001) skin. In glabrous skin, neural activity increased from 11 ± 1% at thermoneutral to 18 ± 1% (p < 0.001). In non-glabrous skin there was an initial decrease (p = 0.001) in neural activity from 13 ± 2% to 9 ± 1% (−0.2 °C decrease in Tre) and then increased (p = 0.002) to 21 ± 2% baseline at −0.5 °C Tre. Endothelial activity decreased in both glabrous (16 ± 3% to 6 ± 1%, p < 0.001) and non-glabrous (15 ± 1% to 7 ± 1%, p = 0.003) skin. Hypothermia elicits large decreases in skin blood flow in both glabrous and non-glabrous skin that are related to increases in neural activity and a reduction of endothelial activity.
•We studied skin vasoconstriction to mild hypothermia, −0.5 °C core temperature.•Hypothermia was elicited by exposure to 0 °C ambient temperature.•In glabrous skin, neural activity increased.•In non-glabrous skin, neural activity initially decreased and then increased.•Endothelial activity decreased in both glabrous and non-glabrous skin.
Galaxies with stellar masses near M* contain the majority of stellar mass in the universe, and are therefore of special interest in the study of galaxy evolution. The Milky Way (MW) and Andromeda ...(M31) have present-day stellar masses near M*, at 5 x 10 super(10) M sub(middot in circle) (defined here to be MW-mass) and 10 super(11) M sub(middot in circle) (defined to be M31-mass). We study the typical progenitors of these galaxies using the FOURSTAR Galaxy Evolution Survey (ZFOURGE). ZFOURGE is a deep medium-band near-IR imaging survey, which is sensitive to the progenitors of these galaxies out to z ~ 3. We use abundance-matching techniques to identify the main progenitors of these galaxies at higher redshifts. We measure the evolution in the stellar mass, rest-frame colors, morphologies, far-IR luminosities, and star formation rates, combining our deep multiwavelength imaging with near-IR Hubble Space Telescope imaging from Cosmic Near-IR Deep Extragalactic Legacy Survey (CANDELS), and Spitzer and Herschel far-IR imaging from Great Observatories Origins Deep Survey-Herschel and CANDELS-Herschel. The typical MW-mass and M31-mass progenitors passed through the same evolution stages, evolving from blue, star-forming disk galaxies at the earliest stages to redder dust-obscured IR-luminous galaxies in intermediate stages and to red, more quiescent galaxies at their latest stages. The progenitors of the MW-mass galaxies reached each evolutionary stage at later times (lower redshifts) and with stellar masses that are a factor of two to three lower than the progenitors of the M31-mass galaxies. The process driving this evolution, including the suppression of star formation in present-day M* galaxies, requires an evolving stellar-mass/halo-mass ratio and/or evolving halo-mass threshold for quiescent galaxies. The effective size and SFRs imply that the baryonic cold-gas fractions drop as galaxies evolve from high redshift to z ~ 0 and are strongly anticorrelated with an increase in the Sersic index. Therefore, the growth of galaxy bulges in M* galaxies corresponds to a rapid decline in the galaxy gas fractions and/or a decrease in the star formation efficiency.
HST WFPC2 observations of Cepheids in M96 (NGC 3368) are used to find a distance to that galaxy of 11.2±1.0 Mpc. This estimate is based on a calibration of the Cepheid period-luminosity relation in ...the Large Magellanic Cloud, and includes a correction for the difference in metallicity between the two systems. There are good reasons for believing M96 is at the same distance as four E/S0 galaxies in the Leo-I group, and hence we calibrate secondary distance indicators based on the early-type galaxies, namely the fundamental plane and surface-brightness-fluctuation method. Also the Type Ia supernova 1998bu occurred in M96 itself and is used to calibrate the SN Ia distance scale. These methods reach to recession velocities of greater than 5000 km s−1 and can therefore allow us to evaluate the Hubble constant without reference to the peculiar velocity of M96 itself. In fact, these indicators agree well between themselves and hence we find H0 = 67±7 km s−1 Mpc−1 where the quoted error includes estimates of potential systematic effects.
The hoot‐calls of Wood Owls Strix woodfordii, recorded in the Kruger National Park, South Africa, from 1986 to 1998, are sufficiently different to distinguish individuals. Thirteen hoot‐call ...variables, measured from recordings over this period, show that male and female Wood Owls have such temporal stability that these calls can be used reliably as a long‐term census technique. manova, based on ordinations from principal component analysis, was used to identify individuals statistically between sampling periods. A forward stepwise discriminant function analysis achieved 100% classification success of individual male (n = 3) and female (n = 4) owls from a single sampling period. For all the individuals recorded over the whole study period we achieved a classification success of 80.9% (n = 9) for male hoot calls and of 96.3% (n = 13) for female calls. We found mean occupation periods of 82.25 and 65 months and annual turnover rates of 19.3% and 13.65% for males and females, respectively. Our survey, using vocalizations, is unique since we use data collected over a 12‐year period to derive estimates of population turnover in Wood Owls, and consider what questions can be addressed in similar studies.
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