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91.
The rise of two sub-specialties in Physical Anthropology traces back to the Anatomy Departments of Schools of Medicine in Germany and France during the nineteenth century. The study of human diversity in bones and bodies was largely by medically-trained anatomists. There developed Medical Anthropology and Dental Anthropology, employing osteometry and craniometry on the skeleton, somatometry and cephalometry on the living body. As a result cross-sectional studies gave way to longitudinal studies and X-ray techniques were added to purely mensurational procedures. In Medical Anthropology the specialties most directly concerned are pediatrics, plastic surgery, endocrinology, and orthopaedics. In Dental Anthropology the specialties most directly concerned are pedodontics, orthodontics, oral surgery, and prosthodontics. The contributions of Physical Anthropology to each is discussed.  相似文献   
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93.
Physical inactivity is most commonly found in socially vulnerable groups. Dutch policies target these groups through community-based health-enhancing physical activity (CBHEPA) programs. As robust evidence on the effectiveness of this approach is limited, this study investigated whether CBHEPA programs contribute to an increase in and the maintenance of physical activity in socially vulnerable groups. In four successive cohorts, starting at a six-month interval, 268 participants from 19 groups were monitored for twelve months in seven CBHEPA programs. Data collection was based on repeated questionnaires. Socio-economic indicators, program participation and coping ability were measured at baseline. Physical activity, health-related quality of life and on-going program participation were measured three times. Self-efficacy and enjoyment were measured at baseline and at twelve months. Statistical analyses were based on a quasi-RCT design (independent t-tests), a comparison of participants and dropouts (Mann-Whitney test), and multilevel modelling to assess change in individual physical activity, including group level characteristics. Participants of CBHEPA programs are socially vulnerable in terms of low education (48.6%), low income (52.4%), non-Dutch origin (64.6%) and health-related quality of life outcomes. Physical activity levels were not below the Dutch average. No increase in physical activity levels over time was observed. The multilevel models showed significant positive associations between health-related quality of life, self-efficacy and enjoyment, and leisure-time physical activity over time. Short CBHEPA programs (10–13 weeks) with multiple trainers and gender-homogeneous groups were associated with lower physical activity levels over time. At twelve months, dropouts'' leisure-time physical activity levels were significantly lower compared to continuing participants, as were health-related quality of life, self-efficacy and enjoyment outcomes. BMI and care consumption scored significantly higher among dropouts. In conclusion, Dutch CBHEPA programs reach socially vulnerable, but not necessarily inactive, groups in terms of socio-economic and health-related quality of life outcomes. Our findings suggest that CBHEPA programs particularly contribute to physical activity maintenance in socially vulnerable groups, rather than to an increase in physical activity behaviour over time.  相似文献   
94.
In order to obtain information about the conformational features of a 2′-O-methylated polyribonucleotide at the nearest neighbor level, a detailed nuclear magnetic resonance study of AmpA was undertaken. AmpA was isolated from alkali hydrolysates of yeast RNA, and proton spectra were recorded at 100 MHz in the Fourier transform mode in D2O solutions, 0.01 M, pH 5.4 and 1.5 at 25°C. 31P spectra were recorded at 40.48 MHz. Complete, accurate sets of nmr parameters derived for each nucleotidyl unit by simulation iteration methods. The nmr data were translated into conformational parameters for all the bonds using procedures developed in earlier studies from these laboratories. It is shown that AmpA exists in aqueous solution with a flexible molecular framework, which shows preferences for certain orientations. The ribose rings exist as a 2E ? 3E equilibrium with the —pA ribose showing a bias for the 3E pucker. The C(4′)—C(5′) bonds of both nucleotidyl units show significant preference (75–80%) to exist in gg conformation. The dominant conformer (80%) about C(5′)—O(5′) of the 5′-nucleotidyl unit is gg′. Even though an unambiguous determination of the orientation of the 3′-phosphate group cannot be made, tentative evidence shows that it preferentially occupies g+ domains [O(3′)—P trans to C(3′)—C(2′)] in which the H(3′) —C(3′)—O(3′)—P(3′) dihedral angle is about 31°. There is reasonable evidence that the 2′-O-methyl preferentially occupies the domain in which the O(2′)—CH3 bond is trans to C(2′)—C(1′). Lowering of pH to 1.5, which results in protonation of both the adenine moieties, causes destacking of AmpA. Such destacking is accompanied by small, but real, perturbations in the conformations about most of the bonds in the backbone. A detailed comparison of the solution conformations of ApA and AmpA clearly shows that 2′-O-methylation strongly influences the conformational preference about the C(3′)—O(3′) bond of the 3′-nucleotidyl unit, in addition to inducing small changes in the overall ribophosphate backbone conformational equilibria. The effect of 2′-O-methylation is such that the C(3′)—O(3′) is forced to occupy preferentially the g+ domain rather than the normally preferred g? domain [O(3′)—P trans to C(3′)—C(4′)] in ApA. The data on ApA and AmpA further reveal that the extent of stacking interaction is less in AmpA compared to ApA. It is suggested that stacked species of AmpA exist as right-handed stacks where the magnitude of ω and ω′ about O(5′)—P and P—O(3′) is about 290°. The reason for the lesser degree of stacking in AmpA compared to ApA is intramolecular interaction between 2′-O-methyl and the flexible O(3′)—P—O(5′) bridge, the interaction causing some perturbation in the magnitudes of ω/ω′, causing destacking. The destacking will lead to an increase in χCN by a few degrees, causing an increase in 2E populations; the latter in turn will shift the 3′ phosphate group from g? to g+ domains. In short, a coupled series of conformational events is envisioned at the onset of destacking, made feasible by the interaction between the 2′-O-methyl group and the swivel O(3′)—P—O(5′) bridge.  相似文献   
95.
In a context of changing carnivore populations worldwide, it is crucial to understand the consequences of these changes for prey populations. The recolonization by wolves of the French Vercors mountain range and the long-term monitoring (2001–2017) of roe deer in this area provided a unique opportunity to assess the effects of wolves on this prey. Roe deer was the main prey of wolves in the west Vercors mountain range during this recolonization. We compared roe deer abundance and fawn body mass in two contrasted areas of a wolf pack territory: a central area (core of the territory characterized by an intense use by wolves) and a peripheral area (used more occasionally). Roe deer population growth rates were lower in the central area between 2001 and 2006, resulting in a decline in roe deer abundance. Roe deer abundance substantially dropped in the two study areas after an extremely severe winter but the abundance of roe deer in the central area facing with wolves was slower to recover and remained at lower abundance levels for 6 years. Fawn body mass was consistently lower in the central area, varied similarly as roe deer abundance, and was not influenced by weather conditions or red deer population abundance. Altogether, the effects of wolves on roe deer in the central area occurred during a 10-year period following the establishment of wolves, through the interplay between wolf predation (before wolves started preying on red deer), harsh winter conditions and possibly naivety of prey to this recolonizing predator.  相似文献   
96.
In cultivated grasses, tillering, spike architecture and seed shattering represent major agronomical traits. In barley, maize and rice, the NOOT‐BOP‐COCH‐LIKE (NBCL) genes play important roles in development, especially in ligule development, tillering and flower identity. However, compared with dicots, the role of grass NBCL genes is underinvestigated. To better understand the role of grass NBCLs and to overcome any effects of domestication that might conceal their original functions, we studied TILLING nbcl mutants in the non‐domesticated grass Brachypodium distachyon. In B. distachyon, the NBCL genes BdUNICULME4 (CUL4) and BdLAXATUM‐A (LAXA) are orthologous, respectively, to the barley HvUniculme4 and HvLaxatum‐a, to the maize Zmtassels replace upper ears1 and Zmtassels replace upper ears2 and to the rice OsBLADE‐ON‐PETIOLE1 and OsBLADE‐ON‐PETIOLE2/3. In B. distachyon, our reverse genetics study shows that CUL4 is not essential for the establishment of the blade–sheath boundary but is necessary for the development of the ligule and auricles. We report that CUL4 also exerts a positive role in tillering and a negative role in spikelet meristem activity. On the other hand, we demonstrate that LAXA plays a negative role in tillering, positively participates in spikelet development and contributes to the control of floral organ number and identity. In this work, we functionally characterized two new NBCL genes in a context of non‐domesticated grass and highlighted original roles for grass NBCL genes that are related to important agronomical traits.  相似文献   
97.
In insect societies, the presence of reproductives or eggs has been shown to shape several biological traits in the colony members. Social interactions are one of these traits that involve modification of the communication system of the entire colony. Many studies described the role of chemical compounds and dominance behaviors in the presence of reproductive but vibratory behaviors received very few investigations. Yet, vibratory behaviors are ideal candidates, particularly for subterranean species like termites, as they could be quickly transmitted through the substrate and could be very diversified (origin, modulation). Here, we investigated whether the presence of reproductives/eggs affects the vibratory behavior (body‐shaking) of workers in the subterranean termite Reticulitermes flavipes. Our results reveal that the presence of reproductives or eggs triggers an increase of workers' body‐shaking, independent of their colony of origin after 24 hr. We hypothesize that vibratory communication could be used to transfer information about the presence of reproductives and eggs to the entire colony, suggesting that vibratory behaviors could serve as an important yet neglected mediator of social regulation.  相似文献   
98.
Environmental Biology of Fishes - Cortisol is recognized as a physiological indicator of stress in fish. However, this hormone is typically measured in plasma samples. In this study, cortisol...  相似文献   
99.
Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern...  相似文献   
100.
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