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A lot of poisonous and harmful smoke flow with high temperature will be produced when there is a fire in coal mine underground. The smoke flow will move along mine roadway and have serious danger for underground personnel and devices. So the paper researched movement rule of fire smoke flow of inclined roadway and horizontal roadway: when fire happens in upstream ventilating roadway, fire smoke flow will move downstream of fire area because of functions of fire pressure and buoyancy effect; when fire happens in downstream ventilating roadway, fire pressure is smaller at early stage of fire, so fire smoke flow will move downward along direction of air flow of roadway; with increasing of fire, fire pressure increases constantly, fire smoke flow will move along direction of fresh air flow when air speed of upstream is lower than critical air speed; function of throttling effect is not obvious at early stage of fire in horizontal roadway, fire smoke flow will move along direction of fresh air flow; with increasing of fire, function of throttling effect increases, fire smoke flow will make reverse movement when value of throttling effect is as big as value of ventilating resistance of roadway. The paper has certain guilding function for relief work of fire of roadway.

Because change of mine gas concentration is influenced by various factors, so prediction of mine gas emission ca't get some variables. To solve the problem, the paper proposed a prediction method of mine gas emission based on time series. It introduced implementation of using AR model of time series to predict mine gas emission in details. The experiment result showed that error rate of prediction for mine gas emission with the method was 4.3% and the prediction is reliable.

In order to predict development status of future safety situation of China's coal industry, a prediction model of simple linear regression for annual death numbers and annual coal production in China's coal industry was established, and the model was used to predict annual death numbers and annual coal production of China's coal industry in three years. The prediction result showed that the model has certain feasibility, which can provide reliable theoretical basis for predicting safety situation of China's coal industry.

Objective: To evaluate the effectiveness and safety of intragastric balloon (IGB) for the treatment of obese Chinese., Methods: IGB was placed into the stomachs of 48 Chinese patients in Hong Kong, 13 males and 35 females; aged 39 +/- 9 (18 - 65), with the mean baseline body weight (BW) of 106 +/- 26 kg and mean body mass index (BMI) of (40 +/- 9) kg/m(2), 34 (70.8%) with coexistent obesity-related morbidities, who failed to respond to other weight reducing treatment, via routine gastroscopy under intravenous conscious sedation. Restricted balanced diet with 1200 kcal/day and exercise of 150 minutes/week were prescribed after the balloon placement. The IGB was removed endoscopically after at most 180 days. Follow-up was conducted once a week during the first month and then once a month., Results: The median hospital stay and treatment duration were 1 (IQR 1:2.25) day and 174 (IQR 166:181) days respectively. The BW, BMI, and waist circumference were significantly decreased after the IGB placement (all P < 0.01) with the mean BW loss of (13 +/- 7) kg, mean BMI loss of (5 +/- 3) kg/m(2), mean excessive body weight loss of (45 +/- 36)%, and mean waist circumference loss of (12 +/- 8) cm. 66.7% of the patients were satisfied with the treatment. No serious complication related to IGB was noted., Conclusion: IGB is a safe and effective device that achieves moderate weight loss in obese Chinese.

Aim: To analyze the clinical and dosimetric predictive factors for radiation-induced esophageal injury in patients with non-small-cell lung cancer (NSCLC) during three-dimensional conformal radiotherapy (3D-CRT)., Methods: We retrospectively analyzed 208 consecutive patients (146 men and 62 women) with NSCLC treated with 3D-CRT. The median age of the patients was 64 years (range 35-87 years). The clinical and treatment parameters including gender, age, performance status, sequential chemotherapy, concurrent chemotherapy, presence of carinal or subcarinal lymph nodes, pretreatment weight loss, mean dose to the entire esophagus, maximal point dose to the esophagus, and percentage of volume of esophagus receiving >55 Gy were studied. Clinical and dosimetric factors for radiation-induced acute and late grade 3-5 esophageal injury were analyzed according to Radiation Therapy Oncology Group (RTOG) criteria., Results: Twenty-five (12%) of the two hundred and eight patients developed acute or late grade 3-5 esophageal injury. Among them, nine patients had both acute and late grade 3-5 esophageal injury, two died of late esophageal perforation. Concurrent chemotherapy and maximal point dose to the esophagus > or =60 Gy were significantly associated with the risk of grade 3-5 esophageal injury. Fifty-four (26%) of the two hundred and eight patients received concurrent chemotherapy. Among them, 25 (46%) developed grade 3-5 esophageal injury (P = 0.0001<0.01). However, no grade 3-5 esophageal injury occurred in patients who received a maximal point dose to the esophagus <60 Gy (P = 0.0001<0.01)., Conclusion: Concurrent chemotherapy and the maximal esophageal point dose > or =60 Gy are significantly associated with the risk of grade 3-5 esophageal injury in patients with NSCLC treated with 3D-CRT.