213 research outputs found
A New Measure of Traditional Values Across Cultures: China and Russia Compared
A new measure of adherence to traditional values was created with the objective of facilitating research within and across cultures and nations. The measure was tested in China (N = 321) and Russia (N = 314) and factor analysis of the data revealed two subscales named Personal Traditional Values (10 items) and Public Traditional Values (6 items). Empirical psychometric testing of the overall 16-item measure and the two subscales strongly supported the validity and reliability of all three measures. Means comparisons conducted to assess how well the measures could be used for cross-cultural comparisons revealed the Russians somewhat more than the Chinese living by traditional values overall, both nations about equal on living according to traditional values in their personal lives, and the Russians significantly more inclined to abide by traditional values in public. Also tested were several social and psychological variables as theoretical predictors of living by traditional values, and Life Satisfaction was tested as a possible correlate of living according to traditional values. Regression analyses on the combined data confirmed that Family Emotional Support, Conscientiousness, Collectivism, and Age were all significant positive predictors of living by traditional values. Additional regressions also found some unique predictors for each nation. These findings and the results of the parametric tests support the use of the new scales for measuring traditional values both within and across cultures
Superconformal Algebras and Mock Theta Functions
It is known that characters of BPS representations of extended superconformal
algebras do not have good modular properties due to extra singular vectors
coming from the BPS condition. In order to improve their modular properties we
apply the method of Zwegers which has recently been developed to analyze
modular properties of mock theta functions. We consider the case of N=4
superconformal algebra at general levels and obtain the decomposition of
characters of BPS representations into a sum of simple Jacobi forms and an
infinite series of non-BPS representations.
We apply our method to study elliptic genera of hyper-Kahler manifolds in
higher dimensions. In particular we determine the elliptic genera in the case
of complex 4 dimensions of the Hilbert scheme of points on K3 surfaces K^{[2]}
and complex tori A^{[[3]]}.Comment: 28 page
Serine- and threonine/valine-dependent activation of PDK and Tor orthologs converge on Sch9 to promote aging
Dietary restriction extends longevity in organisms ranging from bacteria to mice and protects primates from a variety of
diseases, but the contribution of each dietary component to aging is poorly understood. Here we demonstrate that glucose and specific amino acids promote stress sensitization and aging through the differential activation of the Ras/cAMP/PKA,PKH1/2 and Tor/S6K pathways. Whereas glucose sensitized cells through a Ras-dependent mechanism, threonine and valine promoted cellular sensitization and aging primarily by activating the Tor/S6K pathway and serine promoted sensitization via
PDK1 orthologs Pkh1/2. Serine, threonine and valine activated a signaling network in which Sch9 integrates TORC1 and Pkh
signaling via phosphorylation of threonines 570 and 737 and promoted intracellular relocalization and transcriptional inhibition of the stress resistance protein kinase Rim15. Because of the conserved pro-aging role of nutrient and growth signaling pathways in higher eukaryotes, these results raise the possibility that similar mechanisms contribute to aging in
mammals
Fermionic representations for characters of M(3,t), M(4,5), M(5,6) and M(6,7) minimal models and related Rogers-Ramanujan type and dilogarithm identities
Characters and linear combinations of characters that admit a fermionic sum
representation as well as a factorized form are considered for some minimal
Virasoro models. As a consequence, various Rogers-Ramanujan type identities are
obtained. Dilogarithm identities producing corresponding effective central
charges and secondary effective central charges are derived. Several ways of
constructing more general fermionic representations are discussed.Comment: 14 pages, LaTex; minor correction
HARPS-N high spectral resolution observations of Cepheids II. The impact of the surface-brightness color relation on the Baade-Wesselink projection factor of eta Aql
The Baade-Wesselink (BW) method of distance determination of Cepheids is used
to calibrate the distance scale. Various versions of this method are mainly
based on interferometry and/or the surface-brightness color relation (SBCR). We
quantify the impact of the SBCR, its slope, and its zeropoint on the projection
factor. This quantity is used to convert the pulsation velocity into the radial
velocity in the BW method. We also study the impact of extinction and of a
potential circumstellar environment on the projection factor. We analyzed
HARPS-N spectra of eta Aql to derive its radial velocity curve using different
methods. We then applied the inverse BW method using various SBCRs in the
literature in order to derive the BW projection factor. We find that the choice
of the SBCR is critical: a scatter of about 8% is found in the projection
factor for different SBCRs in the literature. The uncertainty on the
coefficients of the SBCR affects the statistical precision of the projection
factor only little (1-2\%). Confirming previous studies, we find that the
method with which the radial velocity curve is derived is also critical, with a
potential difference on the projection factor of 9%. An increase of 0.1 in
E(B-V) translates into a decrease in the projection factor of 3%. A 0.1
magnitude effect of a circumstellar envelope (CSE) in the visible domain is
rather small on the projection factor, about 1.5%. However, we find that a 0.1
mag infrared excess in the K band due to a CSE can increase the projection
factor by about 6%. The impact of the surface-brightness color relation on the
BW projection factor is found to be critical. Efforts should be devoted in the
future to improve the SBCR of Cepheids empirically, but also theoretically,
taking their CSE into account as well.Comment: Accepted for publication in Astronomy & Astrophysic
Adaptive sliding-mode observer for second order discrete-time MIMO nonlinear systems based on recurrent neural-networks
Recommended from our members
Surface brightness-colour relations of dwarf stars from detached eclipsing binaries: I. Calibrating sample
Aims. Surface brightness - colour relations (SBCRs) are very useful tools for predicting the angular diameters of stars. They offer the possibility to calculate very precise spectrophotometric distances by the eclipsing binary method or the Baade-Wesselink method. Double-lined Detached Eclipsing Binary stars (SB2 DEBs) with precisely known trigonometric parallaxes allow for a calibration of SBCRs with unprecedented precision. In order to improve such calibrations, it is important to enlarge the calibration sample of suitable eclipsing binaries with very precisely determined physical parameters. Methods. We carefully chose a sample of ten SB2 DEBs in the solar neighbourhood which contain inactive main-sequence components. The components have spectral types from early A to early K. All systems have high-precision parallaxes from the Gaia mission. We analysed high precision ground- and space-based photometry simultaneously with the radial velocity curves derived from HARPS spectra. We used spectral disentangling to obtain the individual spectra of the components and used these to derive precise atmospheric parameters and chemical abundances. For almost all components, we derived precise surface temperatures and metallicities. Results. We derived absolute dimensions for 20 stars with an average precision of 0.2% and 0.5% for masses and radii, respectively. Three systems show slow apsidal motion. One system, HD 32129, is most likely a triple system with a much fainter K6V companion. Also three systems contain metallic-line components and show strong enhancements of barium and ittrium. Conclusions. The components of all systems compare well to the SBCR derived before from the detached eclipsing binary stars. With a possible exception of HD 32129, they can be used to calibrate SBCRs with a precision better than 1% with available Gaia DR3 parallaxes
The Araucaria Project: Improving the cosmic distance scale
The book consists of a number of short articles that present achievements of
the Araucaria members, collaborators, and friends, in various aspects of
distance determinations and related topics. It celebrates the 20-year
anniversary of the Araucaria Project, acknowledges the people who worked for
its success, and popularises our methods and results among broader readership.
This book is a part of a project that has received funding from the European
Union's Horizon 2020 research and innovation programme under grant agreement No
695099.Comment: 114 pages, book published in 2021 on behalf of the Nicolaus
Copernicus Astronomical Center of the Polish Academy of Sciences, to
celebrate 20 years of the Arauria Projec
The binary system of the spinning-top Be star Achernar
Achernar, the closest and brightest classical Be star, presents rotational
flattening, gravity darkening, occasional emission lines due to a gaseous disk,
and an extended polar wind. It is also a member of a close binary system with
an early A-type dwarf companion. We aim to determine the orbital parameters of
the Achernar system and to estimate the physical properties of the components.
We monitored the relative position of Achernar B using a broad range of high
angular resolution instruments of the VLT/VLTI (VISIR, NACO, SPHERE, AMBER,
PIONIER, GRAVITY, and MATISSE) over a period of 13 years (2006-2019). These
astrometric observations are complemented with a series of more than 700
optical spectra for the period from 2003 to 2016. We determine that Achernar B
orbits the Be star on a seven-year period, eccentric orbit (e = 0.7255 +/-
0.0014) which brings the two stars within 2 au at periastron. The mass of the
Be star is found to be mA = 6.0 +/- 0.6 Msun for a secondary mass of mB = 2.0
+/- 0.1 Msun. We find a good agreement of the parameters of Achernar A with the
evolutionary model of a critically rotating star of 6.4 Msun at an age of 63
million years. We also identify a resolved comoving low-mass star, which leads
us to propose that Achernar is a member of the Tucana-Horologium moving group.
Achernar A is presently in a short-lived phase of its evolution following the
turn-off, during which its geometrical flattening ratio is the most extreme.
Considering the orbital parameters, no significant interaction occurred between
the two components, demonstrating that Be stars may form through a direct,
single-star evolution path without mass transfer. Since component A will enter
the instability strip in a few hundred thousand years, Achernar appears to be a
promising progenitor of the Cepheid binary systems.Comment: 27 pages, Astronomy & Astrophysics, in press. The full set of
continuum normalized high resolution spectra of Achernar is available at
https://doi.org/10.5281/zenodo.697730
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