[Preparation and luminescent performance of Tb3+ doped SiO2 core-shell nanoparticles].

The authors synthesized the core-shell nanoparticles of SiO2-coated SiO2:Tb3+ by using sol-gel method (SiO2:Tb3+ @SiO2), and studied the influence of core-shell ratio and preparation craftwork on its luminescence properties. The photograph of TEM and EDS showed that SiO2:Tb3+ were coated successfully by SiO2. The authors found that the samples of SiO2:Tb3+ @SiO2 prepared by mixing of core and shell after shell aging with the ratio of core/shell being 1.2 g/25 mL had the stronger fluorescence intensity. Time-resolved spectra showed that the SiO2:Tb3+ @SiO2 had longer fluorescence life time than SiO2:Tb3+.

[Influence of the amount of H2O on the emission spectra of Tb doped SiO2 xerogels].

Tb-doped luminescent SiO2 xerogel was prepared by the sol-gel technique. FTIR was used to measure the microstructure of the luminescent materials. The luminescence properties were characterized by F-7000 UV-visible fluorescence spectrophotometer. The effects of the molar ratio of H2O on the fluorescence and phosphorescence intensity and phosphorescence lifetime of the sample were mainly investigated. The results showed that for the Tb3+ doped xerogels, the sample of 1 : 4 : 4 annealed at 650 degrees C reaches the maximum intensity, the sample of 1 : 4 : 5 annealed at 750 degrees C reaches the maximum, the sample of 1 : 4 : 6 annealed at 850 degrees C is the strongest. With increasing the amount of water, the luminous intensity of the samples annealed at 750 degrees C was first weakened, then enhanced and finally weakened. It was shown that the luminous intensity of samples is related to the molar ratio of aqueous solutions and annealing temperature, whose influence on the luminous intensity formed a competitive mechanism. Phosphorescence was observed at the same time, illustrating the existence of defects in the matrix space, and that the influence of water on the intensity is the same as that of fluorescence. In addition, with the increase in the molar ratio of aqueous solutions, the amount of defect gradually changed and resulted in a change in the luminescence decay time.

A reliable detachable balloon that prevents abdominal cavity contamination during transrectal natural orifice transluminal endoscopic surgery.

OBJECTIVE: To evaluate the efficacy and safety of a detachable endoluminal balloon in the prevention of abdominal cavity contamination during transrectal natural orifice transluminal endoscopic surgery (NOTES). METHODS: The efficacy and safety of a detachable endoluminal balloon to maintain disinfection in the distal colon of the pigs were evaluated. The bacterial loads and colonic cleanliness were monitored. Additionally, the device was applied to another nine pigs that underwent a cholecystotomy by transrectal NOTES. Necropsy and pathological examination were performed after 28-day follow-up. RESULTS: All animals exposed to the device and one of the seven pigs not exposed to the device scored three points on the bowel cleanliness scale (P < 0.001). After 30 min bacterial loads of the test (with balloon occlusion) and control (without balloon occlusion) groups showed a significant difference (0.8 × 103 CFU/mL vs 186.8 × 103 CFU/mL, P < 0.01). Cholecystotomy by transrectal NOTES with the device was successfully performed. The mean intraperitoneal procedure time was 102.9 ± 37.7 min. There were no procedure-related adverse events. During the follow-up, all animals presented normal behavior and appetite. No peritoneal infection or adhesion was detected at autopsy. Cholecystotomy and rectal incision were histologically healed and no histological abnormalities were detected in the colon related to balloon placement. CONCLUSIONS: The detachable balloon provides a reliable solution for preventing peritoneal contamination during transluminal operations. The technique may assist in future transrectal NOTES.

[Analysis on the long-term trend of injury related deaths in Macheng of Hubei province, 1974-2008].

OBJECTIVE: To study the long-term trend of injury related deaths, the distribution of causes of injuries as well as disease burden in Macheng city, Hubei province, in 1974 - 2008. METHODS: Data was gathered from vital statistics and registration system of Macheng city which was established in 1974. Data related to Cause Eliminated Life Expectancy (CELE), years of potential life lost (YPLL) and proportion of YPLL on total deaths were calculated. RESULTS: The injury death rates varied between 62.64/100 000 and 154.97/100 000 during that 35 years. In males and females, injury death rates varied between 69.16/100 000 - 163.86/100 000 and 55.34/100 000 - 157.35/100 000, respectively. Death rates on injury in males exceeded those of females. The average infant injury mortality was 770.13/100 000, stayed the highest in all of the age groups. In terms of geographic region, death rate showed the highest in the hilly area (37.03/100 000), followed by mountainous area (33.66/100 000) and the rate was lowest in the plain area (31.43/100 000). In terms of causes of deaths, suicide, drowning, suffocation, traffic accident and fall were the five top causes of injury, accounting for 84.26% of all the injury mortality. The mortality of suicide showed highest in the injury mortality accounting for 48.14% of all the injury mortality. Injury was the main causes of death among children and youths. The mortality of injury was the highest in people aged from 15 to 29 years, with 59.38% in males and 62.26% in females. Injury eliminated life expectancy increased while the YPLL due to injury decreased, annually. CONCLUSION: Although the trends of mortality rates on injuries were declining over the past 10 years, it remained high in figures. The main causes of injury shifted around, but suicide had always been the main cause over the years, in different age groups, sex or terrains. The death rate of traffic accident was increasing. Effective control strategies should be formulated based on the caused of death related to injuries and among the high-risk populations.