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The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Abnormalities in reward circuit function are considered a core feature of addiction. Yet, it is still largely unknown whether these abnormalities stem from chronic drug use, a genetic predisposition, or both.
In the present study, we investigated this issue using a large sample of adolescent children by applying structural equation modeling to examine the effects of several dopaminergic polymorphisms of the D1 and D2 receptor type on the reward function of the ventral striatum (VS) and orbital frontal cortex (OFC), and whether this relationship predicted the propensity to engage in early alcohol misuse behaviors at 14 years of age and again at 16 years of age.
The results demonstrated a regional specificity with which the functional polymorphism rs686 of the D1 dopamine receptor (DRD1) gene and Taq1A of the ANKK1 gene influenced medial and lateral OFC activation during reward anticipation, respectively. Importantly, our path model revealed a significant indirect relationship between the rs686 of the DRD1 gene and early onset of alcohol misuse through a medial OFC × VS interaction.
These findings highlight the role of D1 and D2 in adjusting reward-related activations within the mesocorticolimbic circuitry, as well as in the susceptibility to early onset of alcohol misuse.
Periodontal diseases (gingivitis and periodontitis), result from a disruption of the host–oral microbiome homoeostasis. Whereas the pathological role of some specific bacterial strains during periodontal diseases is well documented, the impact of parasites in periodontium pathophysiology is still under debate. This review aims to collect data about the prevalence and the potential role of Trichomonas tenax during periodontal diseases. Data from 47 studies revealed that T. tenax prevalence in diseased periodontium ranged from 0 to 94·1%. The prevalence of oral protozoan infections was found to be largely greater in patients with periodontal diseases than with healthy periodontium. The parasite detection was mainly performed by direct microscopy. Trichomonas tenax presence was clearly correlated with periodontal disease. The high heterogeneity of its periodontal prevalence may be correlated with the diversity of the population screened (age, sex, systemic diseases), and the methods used for diagnosis. This protozoan seems to have the capacity to be involved in the inflammatory process of gum disease. Animal experimentation, using relevant physiopathological models of periodontitis, needs to be performed to investigate the ability of T. tenax to cause and/or worsen the disease. Further investigations using standardized experimental designs of epidemiologic studies are also needed.
We explored age-dependent patterns in haemagglutination inhibition (HI) titre to seasonal [1956 A(H1N1), 1977 A(H1N1), 2007 A(H1N1)] and pandemic [A(H1N1)pdm09] influenza strains using serological data collected from an adult French influenza cohort. Subjects were recruited by their general practitioners from 2008 to 2009 and followed until 2010. We explored age-related differences between strain-specific HI titres using 1053 serological samples collected over the study period from 398 unvaccinated subjects. HI titres against the tested seasonal and pandemic strains were determined using the HI technique. Geometric mean titres (GMTs) were estimated using regression models for interval-censored data. Generalized additive mixed models were fit to log-transformed HI estimates to study the relationship between HI titre and age (age at inclusion and/or age at initial strain circulation). GMT against one strain was consistently highest in the birth cohort exposed to that strain during childhood, with peak titres observed in subjects aged 7–8 years at the time of initial strain circulation. Our results complete previous findings on influenza A(H3N2) strains and identify a strain-dependent relationship between HI titre and age at initial strain circulation.
The construction of a prototype telescope is now reaching the stage of mirror polishing and building the active cell. Three blanks have already been produced. Two polishing methods are tested, utilizing the stressing technics, or involving excentered polishing strokes. A working model of one leg of the telescope translator has been built.
We have assembled the asteroid proper elements computed by different authors, using different methods, and for different regions of the asteroid belt. Asteroids on planet crossing orbits are not yet included. The use of very different algorithms is dictated by the dynamics of the different regions. For the asteroids of the main belt, having semimajor axes between 2.1 and 3.8 AU, and with proper eccentricity and sine of inclination less than 0.3, proper elements are computed by a fully analytical iterative theory developed by Milani and Knežević (1990,1992,1994; hereafter M&K). For high inclination and/or eccentricity main-belt asteroids, having 1.8 < a < 3.8 AU and either e or sin I larger than 0.24, proper elements are computed by a semianalytical theory developed by Lemaitre and Morbidelli (1994; hereafter L&M). For Trojans, proper elements are computed by a synthetic theory (that is, from the output of a numerical integration for a few Myr) by Milani (1993). For the Hilda asteroids in the 3: 2 resonance, proper elements have been computed by a synthetic theory by Schubart (1982, 1991). For a discussion of the state of the art in the computation of proper elements, see Knežević and Milani, this volume; for Trojans, see Milani, this volume; for some other cases (e.g. proper elements for resonant asteroids), see Froeschlé and Morbidelli, this volume. When and if new proper elements will be available for other asteroids, they will be added to the public domain file, together with updates and upgrades of the existing catalogues.
In the context of the search of asteroid families (i.e. identification of minor planets as potential fragments of an old bigger body), the calculation of proper elements plays an important role. They are quasi-invariants of the motion, obtained by a double averaging process of the restricted N-body problem; firstly the osculating elements are averaged over the short periodic terms (namely the longitudes of the asteroid and of the perturbing planets) so to get the mean elements, and secondly, the mean elements are averaged over the long periodic terms (longitudes of the pericenters and of the nodes of the asteroid and of the perturbing planets) to obtain the proper elements.
During the past three years observational and theoretical work has been uncommonly extensive and fruitful in two of the fields within the interests of Commission 28—namely, the distribution of external galaxies and the analysis of diffuse nebulosity, the latter including interstellar absorbing material. Important work is also under way at a number of observatories in the interpretation of planetary nebulae. Studies of clusters, however, have been limited to a few active workers, and progress has not been rapid in the analysis of individual galaxies.
1. Since the field covered by Commission No. 28 extends over the problems of three very different types of objects—external galaxies, galactic nebulae, and star clusters—it has been proposed occasionally that the Commission might well be subdivided, or possibly eventually split into three separate Commissions. As Trumpler points out, these three fields “have often been grouped together...more on a historical basis than on an actual similarity of the researches... which are more and more drifting apart.” But some members of the Commission have noted that a distinct difference also separates globular clusters and galactic clusters; and that planetary nebulae and dark absorbing clouds involve at times widely different types of investigations. The chairman of the Commission has made a canvass of the opinions of the members and finds that a large majority believe that no division or subdivision is advisable at this time. It is suggested that the organization or reorganization of a Commission should be left to the Union as a whole or to the Executive Committee.
This Comm. 20 triennial report is prepared as a short summary of the scientific progress in the fields of interest, where, by necessity, only a few highlights are to be mentioned. On the Comm. 20 webpage, the interested reader may find a more complete list of recent references to the relevant literature. Its URL at the time of writing (October 1999) is www.astro.uu.se/IAU/c20/, but mirror sites are expected to have been set up at the time of appearance of these Transactions.
Research in Celestial Mechanics, for the past three years, has mainly focused on the understanding of Chaos on all its aspects. The always larger number of potential applications (meteors, KBO, NEA, asteroids of the main belt but also exoplanets or galactic motions) and the development of new efficient tools, like the symplectic integrators, have allowed the passage from QUALITATIVE models (for example the transfer mechanisms) to real QUANTITATIVE results (like the calculation of lifetimes). This important step has contributed to (re)create collaborations between theoreticians and observers (for example, in the prediction of catastrophic impacts) and to situate the Celestial Mechanics in a wider scientific context.
Aspheric diffraction gratings have been produced by the elastic relaxation method. These gratings lead to more efficient spectrograph mounting arrangements since, for a wide field instrument of fast aperture ratio, a smaller number of optical surfaces are required. The UV-PRIM spectrograph is the first instrument of this type to have been constructed.
The basic principle of the camera described by Bernard Schmidt in 1932 is that a single concave mirror with a stop at its center of curvature has no unique axis and therefore yields equally good images at all points of its yield. The field is curved, and to correct the spherical aberration produced by the mirror, Schmidt introduced, in the stop at the center of curvature of the mirror, a thin non spherical corrector plate of glass. Around 1930 at the Hamburg Observatory and in spite of many difficulties, it was Schmidt's genius as an optician that succeeded - after several judiciously interpreted trials - in figuring a corrector plate by elastic relaxation, and thus demonstrated the optical performance of this new generation of instruments.