[A matched nested case-control study on the risk factors of metabolic syndrome among male criminal policemen].

OBJECTIVE: To explore the risk factors and their differences of metabolic syndrome (MS) on male criminal police, thereby provide the scientific basis to make prevention and control strategies about the metabolic syndrome for the criminal police career. METHODS: Based on physical examination data of criminal police in 2010, 439 patients with MS (CDS) were randomly selected as cases. And as the 1:2 matched nested case-control study, 878 health controls were employed, which were matched with on the basis of sex and age (±1 year). An face-to-face epidemiological investigations on the past exposure status of several possible risk factors was conducted, such as the family history of hypertension and other social economic status, as well as body height and weight, waist circumference, blood pressure, serum lipid and plasma sugar. and the data were analyzed with logistic regression. RESULTS: 1317 cases were surveyed, through single factor logistic regression analysis found that 12 factors are related to exposure. Multivariate logistic regression analysis suggested that six factors, such as stress events (OR = 1.989, 95%CI: 1.467∼2.696), snoring (OR = 1.672, 95%CI: 1.218∼2.294), sweets (OR = 0.562, 95%CI: 0.412∼0.766), meat and products (OR = 1.494, 95%CI: 1.065∼2.094), siting after dinner for more than 3 h (OR = 1.399, 95%CI: 1.023∼1.915). CONCLUSIONS: MS has become a important public health problems among criminal police. For their professional special, a series of bad habits , unhealthy life style and psychological problems became important risk factors of MS on criminal police. Targeted prevention and control measures should be taken to reduce the incidence of MS.

Measurement and analysis of water vapor inside optical components for optical fiber H2O sensing system.

Water vapor existing inside internal end-face gaps of optical components of an optical fiber H2O sensing system makes it possible to influence the measurement accuracy and stability. The influence principle has been briefly analyzed based on the structure of three main optical components: a distributed feedback laser diode (DFB-LD), a collimator, and a photoelectric diode (PD). With application of a differential technique, the influence of water vapor inside the DFB-LD can be removed. With reasonable recombination of the collimator and the PD in a dual-beam detection system, the influence of water vapor inside the collimator and the PD's end-face gaps has been suppressed from more than 1.57×10(-3) to as low as -2.175×10(-5) in absorbance. After H2O isolation processing water vapor inside the end-face gaps of the DFB-LD, the collimator, and the PD can be utilized as a reference to design a simple but feasible H2O sensor. As a result, good linearity with an R2 of 0.9964 has been realized in a concentration range of 39-2110 ppm during an application test, and a long-term test of the designed H2O sensor against the S8000 with a difference of 10 ppm has been achieved.