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There is a need to facilitate acquisition of real world cognitive multi-tasks that require long periods of training (e.g., air traffic control, intelligence analysis, medicine). Non-invasive brain stimulation-specifically transcranial Direct Current Stimulation (tDCS)-has promise as a method to speed multi-task training. We hypothesized that during acquisition of the complex multi-task Space Fortress, subtasks that require focused attention on ship control would benefit from tDCS aimed at the dorsal attention network while subtasks that require redirection of attention would benefit from tDCS aimed at the right hemisphere ventral attention network. We compared effects of 30 min prefrontal and parietal stimulation to right and left hemispheres on subtask performance during the first 45 min of training. The strongest effects both overall and for ship flying (control and velocity subtasks) were seen with a right parietal (C4, reference to left shoulder) montage, shown by modeling to induce an electric field that includes nodes in both dorsal and ventral attention networks. This is consistent with the re-orienting hypothesis that the ventral attention network is activated along with the dorsal attention network if a new, task-relevant event occurs while visuospatial attention is focused (Corbetta et al., 2008). No effects were seen with anodes over sites that stimulated only dorsal (C3) or only ventral (F10) attention networks. The speed subtask (update memory for symbols) benefited from an F9 anode over left prefrontal cortex. These results argue for development of tDCS as a training aid in real world settings where multi-tasking is critical.

The proliferation of portable communication and entertainment devices has introduced new dangers to the driving environment, particularly for young and inexperienced drivers. Graduate students from George Mason University illustrate a powerful, practical, and cost-effective program that has been successful in educating these drivers on the dangers of texting while driving, which can easily be adapted and implemented in other communities.

Aqueous-ammonia-steeped switchgrass was subject to simultaneous saccharification and fermentation (SSF) in two pilot-scale bioreactors (50- and 350-L working volume). Switchgrass was pretreated by soaking in ammonium hydroxide (30%) with solid to liquid ratio of 5 L ammonium hydroxide per kilogram dry switchgrass for 5 days in 75-L steeping vessels without agitation at ambient temperatures (15 to 33 degrees C). SSF of the pretreated biomass was carried out using Saccharomyces cerevisiae (D(5)A) at approximately 2% glucan and 77 filter paper units per gram cellulose enzyme loading (Spezyme CP). The 50-L fermentation was carried out aseptically, whereas the 350-L fermentation was semiaseptic. The percentage of maximum theoretical ethanol yields achieved was 73% in the 50-L reactor and 52-74% in the 350-L reactor due to the difference in asepsis. The 350-L fermentation was contaminated by acid-producing bacteria (lactic and acetic acid concentrations approaching 10 g/L), and this resulted in lower ethanol production. Despite this problem, the pilot-scale SSF of aqueous-ammonia-pretreated switchgrass has shown promising results similar to laboratory-scale experiments. This work demonstrates challenges in pilot-scale fermentations with material handling, aseptic conditions, and bacterial contamination for cellulosic fermentations to biofuels.

Free associations reveal a close relationship between drug use and such psychological dispositions as dominant perceptions, attitudes, and systems of mental representations. The investigations reported here address the relationship of perceived harm or appeal of drugs, age, and reported drug use through analysis of the free associations of students from elementary to graduate school. Subsamples of drug users and non-users are also included. Comparisons across the range of years studied (10 to 29) showed how subjective meanings and the system of mental representation, including those characteristic of drug users and non-users, evolve as a function of age. Based on the domains studied, the distance measured between user/non-user groups and between age groups showed systematic and predictable increases reflecting on construct validity. The perceptual and motivational dispositions identified were significantly correlated with drug use (behavioral validation). The results offer new insights into the role of such variables as perceived harm and subjective appeal.

The stability of solutions of nitroglycerin in several common pharmaceutical solvents and compounds used as tablet excipients was investigated using a UV spectrophoto metric assay. Included in the study were povidone (I), polyethylene glycol 400 (II), and solvents such as absolute alcohol, propylene glycol, and glycerol. At the elevatted temperatures of the accelerated stability studies, only II demonstrated a considerable adverse effect on the stability of the nitroglycerin solution. It is postulated that a "reaction compound" was formed between nitroglycerin and II which regenerated nitroglycerin depending on hydrolysis conditions. Based on the Arrhenius equation and with initial rates of up to 6 hr of degradation, the predicted stability for a II solution of nitroglycerin in terms of its 10% decomposition at 25 degrees was approximately 7 days.

A 67-year-old man presented with epigastric pain and underwent cholecystectomy for acute acalculus cholecystitis. Exploration revealed a large aneurysm in the hepatic artery. One week later, the patient developed jaundice, ascending cholangitis and common bile duct obstruction. He was treated with percutaneous transhepatic drainage with dramatic improvement, then underwent an emergency aneurysm resection operation. He is now well, 8 months postoperatively. Due to the high mortality rate associated with hepatic artery aneurysm, treatment is primarily surgical with aneurysmorrhaphy or direct arterial reconstruction utilizing either autogenous saphenous vein or prosthetic grafts. For inaccessible aneurysms or when patients are unfit to withstand surgery, embolization is a useful alternative.