7,685 research outputs found
Electronic structure and magnetism in the frustrated antiferromagnet LiCrO2
LiCrO2 is a 2D triangular antiferromagnet, isostructural with the common
battery material LiCoO2 and a well-known Jahn-Teller antiferromagnet NaNiO2. As
opposed to the latter, LiCrO2 exibits antiferromagnetic exchange in Cr planes,
which has been ascribed to direct Cr-Cr d-d overlap. Using LDA and LDA+U first
principles calculations I confirm this conjecture and show that (a) direct d-d
overlap is indeed enhanced compared to isostructural Ni and Cr compounds, (b)
p-d charge transfer gap is also enhanced, thus suppressing the ferromagnetic
superexchange, (c) the calculated magnetic Hamiltonian maps well onto the
nearest neighbors Heisenberg exchange model and (d) interplanar inteaction is
antiferromagnetic.Comment: 5 pages, 4 figure
The pressure-amorphized state in zirconium tungstate: a precursor to decomposition
In contrast to widely accepted view that pressure-induced amorphization arises due to kinetic hindrance of equilibrium phase transitions, here we provide evidence that the metastable pressure-amorphized state in zirconium tungstate is a precursor to decomposition of the compound into a mixture of simple oxides. This is from the volume collapse ΔV across amorphization, which is obtained for the first time by measuring linear dimensions of irreversibly amorphized samples during their recovery to the original cubic phase upon isochronal annealing up to 1000 K. The anomalously large ΔV of 25.7 ± 1.2% being the same as that expected for the decomposition indicates that this amorphous state is probably a precursor to kinetically hindered decomposition. A P–T diagram of the compound is also proposed
Association of Breakfast Intake with Obesity, Dietary and Physical Activity Behavior Among Urban School-Aged Adolescents in Delhi, India: Results of a Cross-Sectional Study
In developed countries, regular breakfast consumption is inversely associated with excess weight and directly associated with better dietary and improved physical activity behaviors. Our objective was to describe the frequency of breakfast consumption among school-going adolescents in Delhi and evaluate its association with overweight and obesity as well as other dietary, physical activity, and sedentary behaviors. Methods: Design: Cross-sectional study. Setting: Eight schools (Private and Government) of Delhi in the year 2006. Participants: 1814 students from 8th and 10th grades; response rate was 87.2%; 55% were 8th graders, 60% were boys and 52% attended Private schools. Main outcome measures: Body mass index, self-reported breakfast consumption, diet and physical activity related behaviors, and psychosocial factors. Data analysis: Mixed effects regression models were employed, adjusting for age, gender, grade level and school type (SES). Results: Significantly more Government school (lower SES) students consumed breakfast daily as compared to Private school (higher SES) students (73.8% vs. 66.3%; p<0.01). More 8th graders consumed breakfast daily vs. 10th graders (72.3% vs. 67.0%; p<0.05). A dose-response relationship was observed such that overall prevalence of overweight and obesity among adolescents who consumed breakfast daily (14.6%) was significantly lower vs. those who only sometimes (15.2%) or never (22.9%) consumed breakfast (p<0.05 for trend). This relationship was statistically significant for boys (15.4 % vs. 16.5% vs. 26.0; p<0.05 for trend) but not for girls. Intake of dairy products, fruits and vegetables was 5.5 (95% CI 2.4-12.5), 1.7 (95% CI 1.1-2.5) and 2.2 (95% CI 1.3-3.5) times higher among those who consumed breakfast daily vs. those who never consumed breakfast. Breakfast consumption was associated with greater physical activity vs. those who never consumed breakfast. Positive values and beliefs about healthy eating; body image satisfaction; and positive peer and parental influence were positively associated with daily breakfast consumption, while depression was negatively associated. Conclusion: Daily breakfast consumption is associated with less overweight and obesity and with healthier dietary-and physical activity-related behaviors among urban Indian students. Although prospective studies should confirm the present results, intervention programs to prevent or treat childhood obesity in India should consider emphasizing regular breakfast consumption.Obesity Prevention Center, University of MinnesotaPRIME program of the University of Texas, School of Public Health (Stigler, PI)Center for Health Promotion and Disease Prevention Research in Underserved Population
Effect of micronutrients on leaf composition, fruit quality and yield of Kinnow mandarin
Effect of micronutrients on leaf composition, quality parameters and fruit yield of Kinnow mandarin was studied at Regional Research Station, Abohar. Foliar application of 1000 ppm Zn + 1000 ppm Mn on Kinnow mandarin during the end of April and mid of August gave maximum fruit yield (862 fruits / tree) and good quality fruits (Higher TSS/Acid: 14.23) by correcting these micronutrient deficiencies. Therefore, application of this dose of micronutrient combination will improve yield and fruit quality in Kinnow mandarin by correcting the deficiencies of these micronutrients as a result of which the orchardist will be economically benefited
United States Economy & The Stock Market
Is this a new economy? Inflation and interest rates are low. Compared to previous recessions, unemployment rates are also low but productivity is growing at a healthy pace. For the first time since the 1920s stock markets have been falling during the first few months of an economic recovery. The U.S. stockholders wealth has been reduced by approximately $8.0 trillion between March 24, 2000 and October 9, 2002. Information technology and telecommunication sectors have lost more than 50 percent of their market value. The U.S. consumer has so far shrugged off the bursting of technology bubble. However, the real estate sector is forming a bubble in some areas now. Of late, the enthusiastic American consumer has shown signs of fatigue in the face of corporate scandals, higher trade deficits and resurfacing of federal deficits. This essay finds that the current bear market is similar to the 1929-1934 bear market in many respects. An important difference between the current market and 1929-1934 period is the participation rate and the presence of defined contribution as well as defined benefit plans
Squared torsion gravity and its cosmological implications
We present the coupling of the torsion scalar and the trace of
energy-momentum tensor , which produces new modified
gravity. Moreover, we consider the functional form
where and are
free parameters. As an alternative to a cosmological constant, the
theory may offer a theoretical explanation of the late-time
acceleration. The recent observational data to the considered model especially
the bounds on model parameters is applied in detail. Furthermore, we analyze
the cosmological behavior of the deceleration, effective equation of state and
total equation of state parameters. However, it is seen that the deceleration
parameter depicts the transition from deceleration to acceleration and the
effective dark sector shows a quintessence-like evolution.Comment: 7 figures, 8 pages Comments are welcom
On the Gelfand-Phillips property in Banach spaces with PRI
It is proved that every Banach space belonging to a certain class called the class possesses the Gelfand-Phillips property. Consequently, so does every weakly countably determined Banach space, every Banach space with an -basis whose dual unit ball is weak angelic and spaces for Valdivia
compact
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