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We theoretically and experimentally investigate the laser-detected magnetic resonance spectra dressed by a radio-frequency magnetic field in F g = 4 of D1 line of cesium atoms. The analytical expression of the transmission spectrum for magnetic resonance dressed by a radio-frequency magnetic field is derived and has substantial agreement with the transmission spectra observed in the experiment. The theoretical prediction of the ratio of the amplitudes of the two sidebands with the detuning is basically consistent with the experimental data, which confirms the validity of the analytical expression. The separation between the two sidebands under resonance shows a highly linear proportion to the amplitude of the dressing field, which may provide a useful scheme for the measurement of radio-frequency magnetic field and magnetic imaging.

We demonstrate a simple technique to lock the frequency of a laser to an atomic transition with a new technique of subnatural linewidth spectroscopy. The coupled rubidium system exhibits an enhanced absorption spectrum of the probe beam with a subnatural linewidth. Compared with other techniques with an additional laser, our scheme only utilizes a single laser, which will be locked. The observed spectroscopic linewidth is down to about 3.5 MHz. The laser frequency fluctuation is about 226 kHz after locking on. The demonstrated scheme offers a convenient and low-cost technique for laser frequency stabilization and related precision measurements.

A DC current sensor based on an optically pumped atomic magnetometer is proposed. It has a high linearity in a wide operation range, since the magnetometer measures the absolute magnitude of the magnetic field produced by the current to be measured. The current sensor exhibits a high accuracy with a non-moment solenoid and magnetic shielding to suppress the influence from the environment. The absolute error of the measured current is below 0.08 mA when the range is from 7.5 mA to 750 mA. The relative error is 5.54 × 10−5 at 750 mA.

Twenty eight male patients with non-pathological fracture neck of femur (FNOF), age range 61-89 years, mean age 74.4 years, presented for surgery for fracture neck of femur to Merlin Park Regional Hospital, Galway Ireland and 28 age and sex matched control patients, age range 60-85 years, mean age 72.4 years who were admitted to the medical ward for various complaints including chest pain, gastroenteritis, and upper respiratory tract infections were included in the study. Following a formal written consent blood were collected for CBC, CMP, and total and free testosterone levels, LH, Estradiol, total 25(OH)D and 1,25(OH)2D, and PTH levels pre-operatively. Bone mineral density was done within 7 days of the incident fracture on the patients and the control groups after enrollment. The study is approved by the local IRB.

Current videoconferencing systems can be roughly divided into two types: a window-type where a computer display works as a window to reveal a remote partner, and a mirror-type whose display shows the mirrored reflections of both participants. While mirror-type systems enhance the feeling of togetherness by merging the two sites into one display, an inherent problem remains. Despite the mirror metaphor, the partner has no physical body in front of the display. To cope with this incongruence, we placed a partition in front of the display. Across that partition we further also placed a robotic table and a robotic bench that move based on the partner's behavior. The experiments indicated that the table and bench successfully facilitated feeling as if there were the partner's physical body was present at the opposite side of the partition.

In China, Grape bagging was done by mostly manual work. In order to improve the intelligence level of grape bagging and reduce the amount of human labor, a robot system for grape bagging was developed. The hardware structure of robot system was designed based on cylindrical coordinate. One kind of grape extraction algorithm based on 2G-R-B was developed. And the control system of grape bagging robot was completed. The robot could realize starting the machine automatically. The performance test of grape bagging robot indicated that the success rate for bagging grape was 85%, and the execution time of a single bagging cycle was 39.6s.

The radiofrequency-optical double magnetic resonance in cesium atoms filled in a vapor cell is investigated experimentally. One resonant signal involving spin-exchange collisions is observed in the MZ type magnetic resonance spectrum. We solve Liouville equations describing the dynamics of the system and analyze the role of the spin-exchange collisions in the atomic population distributions under resonant conditions. The theoretical calculations agree very well with the experimental results. In contrast with the normal magnetic resonance, the collision induced magnetic resonance exhibits the interesting saturation effect: both the signal amplitude and the signal linewidth are nearly constant when the laser intensity is above a moderate threshold value, which can be useful for precision measurements of the geomagnetic field.