Development of two-color laser system for high-resolution polarization spectroscopy measurements of atomic hydrogen.

We have developed a high-spectral-resolution laser system for two-photon pump, polarization spectroscopy probe (TPP-PSP) measurements of atomic hydrogen in flames. In the TPP-PSP technique, a 243-nm laser beam excites the two-photon 1S-2S transition, and excited n=2 atoms are then detected by polarization spectroscopy of the n=2 to n=3 transition using 656-nm laser radiation. The single-frequency-mode 243 and 656-nm beams are produced using injection-seeded optical parametric generators coupled with pulsed dye amplifiers. The use of single-mode lasers allows accurate measurement of signal line shapes and intensities even with significant pulse-to-pulse fluctuations in pulse energies. Use of single-mode lasers and introduction of a scheme to select nearly constant laser energies enable repeatable extraction of important spectral features in atomic hydrogen transitions.

Differences in consumption of food items between obese and normal-weight people in India.

BACKGROUND: There is a rising prevalence of obesity in India, and diet may be a major determinant of this. We aimed to assess differences in types and quantities of food items consumed by obese and normal-weight people in India. METHODS: Cross-sectional data of 7067 factory workers and their families were used from the Indian Migration Study, conducted in four cities across northern, central and southern India. Food frequency questionnaire data were used to compare the quantities of consumption of 184 food items between 287 obese (body mass index>30 kg/m2) and 1871 normalweight (body mass index 18.50-22.99 kg/m2) individuals, using t tests and ANCOVAs. Individuals with diabetes,hypertension and cardio-vascular disease were excluded. SPSS 16.0 was used for analysis. RESULTS: After adjusting for age, sex, location and socioeconomic status, obese individuals were found to eat significantly larger quantities of 11 food items compared with normalweight individuals. These included phulkas, chapatis/parathas/naan, plain dosa, mutton/chicken pulao/biryani, chicken fried/grilled, rasam, mixed vegetable sagu, vegetable raitha, honey,beetroot and bottlegourd (p< 0.01). Consumption of plain milk was higher among normal-weight than among obese individuals (p< 0.05). Consumption of some of these food items was also found to increase by socioeconomic status, decrease by age, and be higher among men relative to women. CONCLUSION: Obese individuals were found to consume larger quantities of certain food items compared with normal weight individuals. Interventions should aim at limiting overall food consumption among obese individuals.

Study of relationship between facial index and gestational age in normal newborns.

Anthropometric dimensions are the basis of evaluation of health of newborns. Results of cephalometric studies can be used in forensic medicine, plastic surgery, pediatrics, oral surgery, dentistry, otolaryngology and syndromology. Three hundred sixty appropriate for gestational age newborns belonging to the region in and around Patiala were the subjects of the present study. The gestational age varied from 29 to 41 weeks. Face length and face width were measured and facial index was calculated. The overall mean face length and mean face width were 5.17 cm and 6.42 cm respectively. Facial index ranged from 79.3 - 81.4% with mean facial index being 80.5%. Facial index increased with increasing gestational age. Gestational age has negative correlation with face length and face width but positively significant correlation was observed between gestational age and facial index. Facial length and facial width were jointly determined. All inter-relationships improved remarkably when determined for gestational age groups. These findings have significant implication as gestational age linearly influenced facial index. In addition they provide database from 29th to 41st week of gestation and can be used as baseline for further anthropometric studies to specify the role of heredity and environment.