Effects of polymer matrix and temperature on pyrolysis of tetrabromobisphenol A: Product profiles and transformation pathways.

Plastics are crucial constituents in electronic waste (e-waste) and part of the issue in e-waste recycling and environmental protection. However, previous studies have mostly focused on plastic recovery or thermal behavior of flame retardants, but not both simultaneously. The present study simulated the process of e-waste thermal treatment to explore tetrabromobisphenol A (TBBPA) pyrolysis at various temperatures using polystyrene (PS), polyvinyl chloride (PVC), and e-waste plastics as polymer matrices. Pyrolysis of TBBPA produced bromophenol, bromoacetophenone, bromobenzaldehyde, and bromobisphenol A. Co-pyrolysis with the polymer matrices increased emission factors by 1 - 2 orders of magnitude. The pyrolytic products of TBBPA, TBBPA+PS, and TBBPA+PVC were mainly low-brominated bisphenol A, while that of TBBPA in e-waste plastics was consistently bromophenol. Increasing temperature drove up the proportions of gaseous and particulate products, but lowered the relative abundances of inner wall adsorbed and residual products in pyrolysis of pure TBBPA. In co-pyrolysis of TBBPA with polymer matrix, the proportions of products in different phases were no longer governed solely by temperature, but also by polymer matrix. Co-pyrolysis of TBBPA with PS generated various bromophenols, while that with PVC produced chlorophenols and chlorobrominated bisphenol A. Transformation pathways, deduced by ab initio calculations, include hydrogenation-debromination, isopropylphenyl bond cleavage, oxidation, and chlorination.

Abdominal wall endometriosis: an overlooked but possibly preventable complication.

OBJECTIVE: To find ways of preventing abdominal wall endometriosis through a retrospective case review. MATERIALS AND METHODS: A retrospective study of 22 patients presenting with 26 postoperative abdominal wall masses. All masses were pathologically proved to be scar endometriosis between September 1994 and September 2006. The age, parity, symptoms and duration, previous surgeries, interval between previous surgery and current operation, initial diagnosis, and the 26 sites and size of endometrioma were recorded and analyzed. RESULTS: About 60% of the patients were in the fourth decade of life. All 22 cases, except one with mid-trimester hysterotomy, had previous cesarean section (CS). Three cases had vertical midline incision for CS, and the other 19 had Pfannenstiel incision, 18 of which were for CS and one for hysterotomy. Of the 22 cases, only three had multiple endometriomas, i.e. one case had three foci and the other two cases had two foci each. Twenty-three endometriomas were found in the Pfannenstiel incision group; 19 out of the 23 foci (82%) were located in either corner of the Pfannenstiel incision wounds (with right side predominance in 13 out of 19). Three endometriomas were noted in vertical midline incisions and two were in the upper corner. Three endometrioma excisions were done during repeated CS. CONCLUSION: Abdominal wall endometriosis may be caused by iatrogenic inoculation of the endometrium into the surgical wound. It is strongly recommended that, at the conclusion of the surgical procedure, the abdominal wound be cleaned thoroughly, particularly at both corner sites (especially the operators side). If an abdominal wall endometriosis is encountered after CS but the patient plans to have future pregnancy and the symptoms are mild, excision of the endometrioma may be deferred until the next indicated CS.

A randomised, double-blind, placebo-controlled trial on the effect of Pycnogenol on the climacteric syndrome in peri-menopausal women.

BACKGROUND: French maritime pine bark extract (Pycnogenol) was found to alleviate menstrual pain and reduce hyperactivity in clinical studies. These results suggest the possibility to observe positive effects in treating climacteric syndrome. OBJECTIVE: Clinical investigation of the effect of Pycnogenol, French maritime pine bark extract, on the climacteric syndrome. METHODS: Some 200 peri-menopausal women were enrolled in a double-blind, placebo-controlled study, and treated with Pycnogenol (200mg) daily. Climacteric symptoms were evaluated by the Women's Health Questionnaire (WHQ), patients were checked for antioxidative status and routine chemistry. A total of 155 women completed the study. RESULTS: All climacteric symptoms improved, antioxidative status increased and LDL/HDL ratio was favourably altered by Pycnogenol. No side effects were reported. CONCLUSION: Pycnogenol may offer an alternative method to reducing climacteric symptoms without unwanted effects.