Work and family: marriage, children, child gender and the work hours and earnings of West German men

We find a strong association between family status and labor market outcomes for recent cohorts of West German men in the German Socio-Economic Panel. Living with a partner and living with a child both have substantial positive effects on earnings and work hours. These effects persist in fixed effects models that control for correlation in time-invariant unobservables that affect both family and work outcomes. Child gender also matters - a first son increases fathers' work hours by 100 hours per year more than a first daughter. There is evidence of son preference in the probability that a German man is observed to be coresiding with a son or a daughter. Men are more likely to remain in the same household with a male child than a female child and girls are underrepresented in the raw data. Controlling for selective attrition in our labor supply model reveals that men who remain with female children are strongly positively selected (in terms of their work hours) relative to men who remain with male children

The Premium of English Proficiency in the South Korean Labor Market

In this paper, we estimate the wage premium of English skills in the Korean labor market using Korean Labor and Income Panel Study (KLIPS) data. In a simple OLS model, we find that people with some English skills in terms of self evaluation or job requirement earn 30% more than those who do not have English skills. But in a small sample of relatively young people, higher English test scores do not raise earnings. When we add SAT scores in the wage equation, there is no wage premium of English skills, and in the IV estimation, we find no English premium. These results consistently imply that while there is a large wage premium of English skills in the Korean labor market, it reflects unobservable ability for the most part. Meanwhile some of the regression results favor human capital theory over screening theory as an explanation of the nature of the wage premium of English skills

A definitive number of atoms on demand: controlling the number of atoms in a-few-atom magneto-optical trap

A few 85Rb atoms were trapped in a micron-size magneto-optical trap with a high quadrupole magnetic-field gradient and the number of atoms was precisely controlled by suppressing stochastic loading and loss events via real-time feedback on the magnetic field gradient. The measured occupation probability of single atom was as high as 99%. Atoms up to five were also trapped with high occupation probabilities. The present technique could be used to make a deterministic atom source.Comment: 3 pages, 4 figure

Lineshape measurement of an extreme-weak amplitude-fluctuating light source by the photon-counting-based second-order correlation spectroscopy

We demonstrate lineshape measurement of an extreme-weak amplitude fluctuating light source by using the photon-counting-based second-order correlation spectroscopy combined with the heterodyne technique. The amplitude fluctuation of a finite bandwidth introduces a low-lying spectral structure in the lineshape and thus its effect can be isolated from that of the phase fluctuation. Our technique provides extreme sensitivity suited for single-atom-level applications.Comment: 3 pages, 3 figure

Calibration of second-order correlation functions for non-stationary sources with a multi-start multi-stop time-to-digital converter

A novel high-throughput second-order-correlation measurement system is developed which records and makes use of all the arrival times of photons detected at both start and stop detectors. This system is suitable particularly for a light source having a high photon flux and a long coherence time since it is more efficient than conventional methods by an amount equal to the product of the count rate and the correlation time of the light source. We have used this system in carefully investigating the dead time effects of detectors and photon counters on the second-order correlation function in the two-detector configuration. For a non-stationary light source, distortion of original signal was observed at high photon flux. A systematic way of calibrating the second-order correlation function has been devised by introducing a concept of an effective dead time of the entire measurement system.Comment: 7 pages, 6 figure

Observation of sub-Poisson photon statistics in the cavity-QED microlaser

We have measured the second-order correlation function of the cavity-QED microlaser output and observed a transition from photon bunching to antibunching with increasing average number of intracavity atoms. The observed correlation times and the transition from super- to sub-Poisson photon statistics can be well described by gain-loss feedback or enhanced/reduced restoring action against fluctuations in photon number in the context of a quantum microlaser theory and a photon rate equation picture. However, the theory predicts a degree of antibunching several times larger than that observed, which may indicate the inadequacy of its treatment of atomic velocity distributions.Comment: 4 pages, 4 figure

Multimodality Imaging Can Help to Doubt, Diagnose and Follow-Up Cardiac Mass

Primary cardiac lymphoma is a very rare form of lymphoma primarily or mainly involving the heart, as in the two cases presented in this report. Various imaging modalities, including coronary computed tomography angiography, cardiac magnetic resonance imaging and positron emission tomography were useful for the characterization and diagnosis of cardiac mass. Pathologic confirmation was successful with endomyocardial biopsy under echocardiographic guidance, intra- and extracardiacally. In primary cardiac lymphoma, diagnosis using multiple modalities may be useful for mass characterization, and for response monitoring after chemotherapy