5,331 research outputs found
Locus of control and savings
Abstract: This paper analyzes the relationship between individuals’ locus of control and their savings behavior, i.e. wealth accumulation, savings rates, and portfolio choices. Locus of control is a psychological concept that captures individuals’ beliefs about the controllability of life events and is a key component of self-control. We find that households with an internal reference person save more both in terms of levels and as a percentage of their permanent incomes. Although the locus-of-control gap in savings rates is largest among rich households, the gap in wealth accumulation is particularly large for poor households. Finally, households with an internal reference person and average net worth hold significantly less financial wealth, but significantly more pension wealth, than otherwise similar households with an external reference person
Magnetotransport in the Kondo model with ferromagnetic exchange interaction
We consider the transport properties in an applied magnetic field of the spin
S=1/2 Kondo model with ferromagnetic exchange coupling to electronic
reservoirs, a description relevant for the strong coupling limit of
underscreened spin S=1 Kondo impurities. Because the ferromagnetic Kondo
interaction is marginally irrelevant, perturbative methods should prove
accurate down to low energies. For the purpose of this study, we use a
combination of Majorana diagrammatic theory with Density Matrix Numerical
Renormalization Group simulations. In the standard case of antiferromagnetic
Kondo exchange, we first show that our technique recovers previously obtained
results for the T-matrix and spin relaxation at weak coupling (above the Kondo
temperature). Considering then the ferromagnetic case, we demonstrate how the
low-energy Kondo anomaly splits for arbitrary small values of the Zeeman
energy, in contrast to fully screened Kondo impurities near the strong coupling
Fermi liquid fixed point, and in agreement with recent experimental findings
for spin S=1 molecular quantum dots.Comment: 14 pages, 13 figures, minor changes in V
GSMBE growth of GaInAsP/InP 1.3 mu m-TM-lasers for monolithic integration with optical waveguide isolator
Selfdual 2-form formulation of gravity and classification of energy-momentum tensors
It is shown how the different irreducibility classes of the energy-momentum
tensor allow for a Lagrangian formulation of the gravity-matter system using a
selfdual 2-form as a basic variable. It is pointed out what kind of
difficulties arise when attempting to construct a pure spin-connection
formulation of the gravity-matter system. Ambiguities in the formulation
especially concerning the need for constraints are clarified.Comment: title changed, extended versio
Electron effective mass in Sn-doped monoclinic single crystal -gallium oxide determined by mid-infrared optical Hall effect
The isotropic average conduction band minimum electron effective mass in
Sn-doped monoclinic single crystal -GaO is experimentally
determined by mid-infrared optical Hall effect to be
combining investigations on () and () surface cuts. This result
falls within the broad range of values predicted by theoretical calculations
for undoped -GaO. The result is also comparable to recent
density functional calculations using the
Gaussian-attenuation-Perdue-Burke-Ernzerhof hybrid density functional, which
predict an average effective mass of (arXiv:1704.06711
[cond-mat.mtrl-sci]). Within our uncertainty limits we detect no anisotropy for
the electron effective mass, which is consistent with most previous theoretical
calculations. We discuss upper limits for possible anisotropy of the electron
effective mass parameter from our experimental uncertainty limits, and we
compare our findings with recent theoretical results
The Association of Infant Feeding Patterns with Food Allergy Symptoms and Food Allergy in Early Childhood
Background: The role of infant feeding for food allergy in children is unclear and studies have not addressed simultaneous exposures to different foods. The goal of this study was to analyze existing data on feeding practices that represent realistic exposure and assess the risk of food allergy symptoms and food allergy in children.
Methods: The Infant Feeding Practices Study II conducted by the CDC and US-FDA enrolled pregnant women and collected infant feeding information using nine repeated surveys. Participants were re-contacted after 6 years. Food allergy data were collected at 4, 9, 12, and 72 months. In total, 1387 participants had complete infant feeding pattern data for 6 months and information on food allergy symptoms and doctors’ diagnosed food allergy. Feeding patterns constituted six groups: 3-months of feeding at breast followed by mixed feeding, 3-months of breast milk and bottled milk followed by mixed feeding, 1-month of feeding at breast followed by mixed feeding, 6-months of mixed feeding i.e., concurrent feeding of breast milk, bottled milk and formula, 2–3 months of formula followed by formula and solid food, and formula and solid food since the first month. To estimate risks of food allergy, we used linear mixed models, controlling for potential confounders.
Results: Of the 328 children with food allergy symptoms in infancy and at 6 years, 52 had persistent symptoms from infancy. Children exposed to mixed feeding had a higher risk of food allergy symptoms (Risk Ratio [RR] 1.54; 95% Confidence Interval [CI] 1.04, 2.29) compared to 3-months of feeding at breast adjusted for confounding. No statistically significant risk of infant feeding patterns was found for doctors’ diagnosed food allergy. Paternal allergy posed a higher risk for food allergy symptoms (RR 1.36; 95% CI 1.01, 1.83). Prenatal maternal smoking increased the risk for doctors’ diagnosed food allergy (RR 2.97; 95% CI 1.53, 5.79).
Conclusions: Analysis of this prospective birth cohort suggest that introduction of multiple feeding source may lead to food allergy symptoms. Future efforts are needed to determine acceptable approaches to improve the ascertainment of food allergy in children and the role of infant feeding
Sex-partitioning of the <i>Plasmodium falciparum</i> stage V gametocyte proteome provides insight into <i>falciparum</i>-specific cell biology
One of the critical gaps in malaria transmission biology and surveillance is our lack of knowledge about Plasmodium falciparum gametocyte biology, especially sexual dimorphic development and how sex ratios that may influence transmission from the human to the mosquito. Dissecting this process has been hampered by the lack of sex-specific protein markers for the circulating, mature stage V gametocytes. The current evidence suggests a high degree of conservation in gametocyte gene complement across Plasmodium, and therefore presumably for sex-specific genes as well. To better our understanding of gametocyte development and subsequent infectiousness to mosquitoes, we undertook a Systematic Subtractive Bioinformatic analysis (filtering) approach to identify sex-specific P. falciparum NF54 protein markers based on a comparison with the Dd2 strain, which is defective in producing males, and with syntenic male and female proteins from the reanalyzed and updated P. berghei (related rodent malaria parasite) gametocyte proteomes. This produced a short list of 174 male- and 258 female-enriched P. falciparum stage V proteins, some of which appear to be under strong diversifying selection, suggesting ongoing adaptation to mosquito vector species. We generated antibodies against three putative female-specific gametocyte stage V proteins in P. falciparum and confirmed either conserved sex-specificity or the lack of cross-species sex-partitioning. Finally, our study provides not only an additional resource for mass spectrometry-derived evidence for gametocyte proteins but also lays down the foundation for rational screening and development of novel sex-partitioned protein biomarkers and transmission-blocking vaccine candidates
Massive Young Stellar Objects in the Galactic Center. I. Spectroscopic Identification from Spitzer/IRS Observations
We present results from our spectroscopic study, using the Infrared
Spectrograph (IRS) onboard the Spitzer Space Telescope, designed to identify
massive young stellar objects (YSOs) in the Galactic Center (GC). Our sample of
107 YSO candidates was selected based on IRAC colors from the high spatial
resolution, high sensitivity Spitzer/IRAC images in the Central Molecular Zone
(CMZ), which spans the central ~300 pc region of the Milky Way Galaxy. We
obtained IRS spectra over 5um to 35um using both high- and low-resolution IRS
modules. We spectroscopically identify massive YSOs by the presence of a 15.4um
shoulder on the absorption profile of 15um CO2 ice, suggestive of CO2 ice mixed
with CH3OH ice on grains. This 15.4um shoulder is clearly observed in 16
sources and possibly observed in an additional 19 sources. We show that 9
massive YSOs also reveal molecular gas-phase absorption from CO2, C2H2, and/or
HCN, which traces warm and dense gas in YSOs. Our results provide the first
spectroscopic census of the massive YSO population in the GC. We fit YSO models
to the observed spectral energy distributions and find YSO masses of 8 - 23
Msun, which generally agree with the masses derived from observed radio
continuum emission. We find that about 50% of photometrically identified YSOs
are confirmed with our spectroscopic study. This implies a preliminary star
formation rate of ~0.07 Msun/yr at the GC.Comment: Accepted for publication in Ap
Detecting the Neutrino Mass Hierarchy with a Supernova at IceCube
IceCube, a future km^3 antarctic ice Cherenkov neutrino telescope, is highly
sensitive to a galactic supernova (SN) neutrino burst. The Cherenkov light
corresponding to the total energy deposited by the SN neutrinos in the ice can
be measured relative to background fluctuations with a statistical precision
much better than 1%. If the SN is viewed through the Earth, the matter effect
on neutrino oscillations can change the signal by more than 5%, depending on
the flavor-dependent source spectra and the neutrino mixing parameters.
Therefore, IceCube together with another high-statistics experiment like
Hyper-Kamiokande can detect the Earth effect, an observation that would
identify specific neutrino mixing scenarios that are difficult to pin down with
long-baseline experiments. In particular, the normal mass hierarchy can be
clearly detected if the third mixing angle is not too small, sin^2 theta_13 <
10^-3. The small flavor-dependent differences of the SN neutrino fluxes and
spectra that are found in state-of-the-art simulations suffice for this
purpose. Although the absolute calibration uncertainty at IceCube may exceed
5%, the Earth effect would typically vary by a large amount over the duration
of the SN signal, obviating the need for a precise calibration. Therefore,
IceCube with its unique geographic location and expected longevity can play a
decisive role as a "co-detector" to measure SN neutrino oscillations. It is
also a powerful stand-alone SN detector that can verify the delayed-explosion
scenario.Comment: 19 pages, 6 Figs, final version accepted by JCAP, some references
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The Wonder of Colors and the Principle of Ariadne
The Principle of Ariadne, formulated in 1988 ago by Walter Carnielli
and Carlos Di Prisco and later published in 1993, is an infinitary principle that is independent of the Axiom of Choice in ZF, although it can be consistently added to
the remaining ZF axioms. The present paper surveys, and motivates, the foundational importance of the Principle of Ariadne
and proposes the Ariadne Game, showing that the Principle of Ariadne,
corresponds precisely
to a winning strategy for the Ariadne Game. Some relations to other
alternative. set-theoretical principles
are also briefly discussed
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