ABSTRACT
Ag2O/TiO2 nanobelt heterostructures have been found to possess high ultraviolet photocatalytic activity, but a poor cycling performance. After a S-doping treatment, the obtained Ag2O/Ag2S2O7/TiO2 heterostructured nanobelts exhibited an enhanced and stable photocatalytic activity under both ultraviolet and visible light irradiation, which was exemplified by photo-degradation of organic pollutants and photocurrent response measurements. Meanwhile, the crystal structure and phase transformation of Ag2O, Ag2S2O7 and Ag2S were studied by XRD and XPS measurements.
ABSTRACT
Newly developed light-activated surgical adhesives have been investigated as a substitute to traditional protein solders for vascular tissue fusion without the need for sutures. Porcine carotid arteries (n = 6) and femoral arteries (n = 6) were exposed, and an incision was made in the arterial walls using a 16G needle. The surgical adhesive, composed of a poly(L-lactic-co-glycolic acid) scaffold doped with the traditional protein solder mix of porcine serum albumin and indocyanine green dye, was used to close the incisions in conjunction with an 805 nm diode laser. Blood flow was restored to the vessels immediately after the procedure and the incision sites were checked for patency. The new adhesives were flexible enough to be wrapped around the vessels while their solid nature avoided the problems associated with "runaway" of the less viscous liquid protein solders widely used by researchers. The strength and hemostatic abilities of the new surgical adhesives were evaluated in the context of arterial pressure, persistence of hemostasis and presence of any inflammatory reaction after 3 days. After this evaluation period, the surgical procedure was repeated on the carotid arteries (n = 6) and femoral arteries (n = 6) of three additional animals that had been heparinized prior to surgery to closer approximate the conditions seen in a typical vascular surgical setting. The patency rate of both the unheparinized and heparinized vessels was 100% at 3 days post-operative with evidence of intraluminal thrombosis seen in only one of the repaired vessels. The adhesive technique also compared favorably with a previous study conducted using conventional suture techniques. Repairs formed with the adhesive technique were achieved more rapidly than suturing, and acute leakage was observed less frequently. Finally, the adhesive technique produced better histology than the suture technique, suggesting that it has great promise as an alternative to suturing. These initial results indicate that laser-assisted vascular repair using the new adhesives is safe, easy to perform, and contrary to conventional suturing, provides an immediate leak-free closure. In addition, the flexible and moldable nature of the new adhesives allows them to be tailored to a wide range of tissue geometries, thus greatly improving the clinical applicability of laser-assisted tissue repair.
Subject(s)
Carotid Arteries/surgery , Femoral Artery/surgery , Lactic Acid , Laser Coagulation , Polyglycolic Acid , Polymers , Tissue Adhesives , Animals , Biomechanical Phenomena , Membranes, Artificial , Polylactic Acid-Polyglycolic Acid Copolymer , Swine , Vascular PatencyABSTRACT
This study describes the relations of patterns of alcohol consumption with Type A behavior, age, retirement, marital status, and socioeconomic status among male participants in the Veterans Administration Normative Aging Study. In April 1984, 1,663 men completed form N of the Jenkins Activity Survey; in September 1982, 1,556 of these men had responded to a mailed survey of drinking behaviors. When age, marital status, socioeconomic status, and retirement status were controlled for, Type A score was virtually unrelated to the probability of being a nondrinker, having three or more drinks per day, problems with drinking, and periodic heavier drinking. Three other measures from the Jenkins Activity Survey--speed and impatience, hard-driving and competitive, and involvement--also had little association with these drinking behaviors. Moderate drinking was found to be strongly associated with higher socioeconomic status and being married. Results suggest that socioeconomic status and possibly marital status, but not Type A behavior and retirement, may influence the relation of drinking with the development of coronary heart disease.