Results of blood chemistry screens of 47 Alzheimer''s disease patients were compared to those of 71 non-Alzheimer''s disease patients with other dementias. Only kidney-related tests differed between the groups (urea nitrogen, creatinine, uric acid and albumin) with the Alzheimer''s disease patients nearer the normal ranges. Multivariate analyses were used to examine whether the simultaneous use of the analytes could aid in diagnosing Alzheimer''s disease. Linear and quadratic discriminant analysis and logistic regression were used to evaluate a number of models. A linear discriminant model of albumin, uric acid, lactate dehydrogenase, and age demonstrated 70–75% classification accuracy using randomly selected test populations of 20%.

This research examined the effect of using separate hydrolysis and methanolysis reactions for biodiesel production using a whole-cell biocatalysts derived from Rhizopus Oryzae (ATCC 10260). Biodiesel yield from separate hydrolysis and methanolysis was compared to transesterification reactions where both hydrolysis and methanolysis reactions occur in the same reactor. All reactions were conducted at room temperature. The effect of substituting ethanol for methanol was also studied. Separating the hydrolysis and methanolysis reactions did not significantly increase biodiesel yields; however, this approach successfully converted about 99% of triglycerides into fatty acid methyl esters (FAME) and free fatty acids (FFA). Use of ethanol in place of methanol did not significantly improve the biodiesel yield. However, there is evidence that ethanol may either esterify FFA more quickly than methanol, or result in a more stable ester. The best biodiesel yield was about 90% when a transesterification reaction using methanol was followed by one hydrolysis and one ethanolysis reaction; however, this is only slightly higher than the 88% biodiesel yield of two transesterification reactions in series (using methanol as alcohol).

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Lignocellulosic feedstocks have high energy content and have been co-digested with sewage or manure biosolids in Europe for many years. However, it is unclear whether the current U.S. anaerobic digesters are capable of co-digesting lignocellulosic feedstocks without experiencing operational problems. We evaluated co-digestion of switchgrass with sewage biosolids under laboratory conditions similar to common U.S. digesters. Results indicated that finely-ground or ensiled switchgrass could be readily co-digested with sewage biosolids under typical U.S. digester conditions. Concentration up to 4% solids (representing up to 47% of VS added) achieved good specific methane yields and up to 74% energy conversion efficiency while maintaining acceptable VS removal. No evidence of solids accumulation, mixing problems, or floating debris was noted. However, fine-grinding switchgrass is energy intensive and likely to be cost-prohibitive. Moreover, ensiling produced a wide array of particle sizes and the effects of ensiling could not be fully separated from effects due to smaller particle size. Coarsely ground switchgrass, however, did not digest well. It had a low specific methane yield and quickly led to digester operational problems, even at the 2% solids level. Further research is needed to identify pretreatment methods that are more practical than fine-grinding. Ensiling appears promising, and should be studied under full-scale ensiling and digestion conditions to assure that observed effects were not due to smaller particle sizes achieved under laboratory conditions. Other, low-cost pretreatment methods also deserve study as a means of allowing lignocellulosic feedstocks to be co-digested in current U.S. anaerobic digesters.

This article suggests reasons for the difficulty in understanding and preventing low-back pain (LBP), provides a framework for understanding the causes of reported LBP, and highlights an important new direction in research that could accelerate progress in reducing LBP. Fundamental to understanding LBP is the recognition that it is a symptom not an underlying condition. Worker reports of LBP depend not only on the extent and nature of underlying injury but also the worker's perceptions and the likelihood of reporting the symptoms. Each of these factors, in turn, depends on a number of other proximal and distal factors. Identifying the root causes of underlying injury is essential to improving prevention programs. Yet, many of the methods used to study LBP and its causes have serious shortcomings, adding to the confusion over appropriate preventive strategies. An important gap in LBP research has been the factors influencing preventive behaviors for both workers and managers. If workers or managers attribute the causes of LBP to the wrong factors, preventive behaviors will be misdirected and ineffective. Attribution theory, a relatively recent application in the occupational health field, offers promise for identifying incorrect attributions and modifying these attributions so that appropriate protective actions are taken.