Cellulose samples with different crystallinities (33-85%) were prepared by treating a commercial cellulose (crystalline, 85%) with phosphoric acid under different conditions. Supported Fe, Co, Ni, Pd, Pt, Rh, Ru, Ir, Ag, and Au catalysts were examined for the conversion of cellulose with a crystallinity of 33% in water medium in the presence of hydrogen, and Ru was found to be the most effective catalyst for the formation of sorbitol. We demonstrated that carbon nanotubes (CNTs) were the most efficient support of Ru for cellulose conversion, and the mean size of Ru nanoparticles over CNT was similar to 8.8 nm. NH3-TPD and H-2-TPD characterizations suggest that plenty of acid sites and unique hydrogen species over the Ru/CNT are important for sorbitol formation through hydrolysis and hydrogenation of cellulose. A 40% yield of hexitols (including 36% of sorbitol) could be achieved over the Ru/CNT catalyst for the conversion of the commercial cellulose (crystalline, 85%), and this yield was the highest one reported to date for the direct conversion of cellulose into sugar alcohols.National Natural Science Foundation of China [20625310, 20773099, 20873110]; National Basic Program of China [2010CB732303, 2005CB221408]; New Century Excellent Talents in Fujian Provinc

Gold nanoparticles loaded on nitric acid-pretreated carbon nanotubes are efficient for the selective oxidation of cellobiose by molecular oxygen to gluconic acid in aqueous medium without pH control; a gluconic acid yield of 80% has been obtained at 145 degrees C.

Cellulose can be transformed into methyl glucosides in methanol with yields of 50-60% in the presence of several acid catalysts under mild conditions (< or = 473 K); H(3)PW(12)O(40) provides the highest turnover number (approximately 73 in 0.5 h) for the formation of methyl glucosides among many acid catalysts examined.

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BackgroundRett syndrome is caused by a pathogenic mutation in the MECP2 gene with major consequences for motor and cognitive development. One of the effects of impaired MECP2 function is reduced production of Brain Derived Neurotrophic Factor (BDNF), a protein required for normal neuronal development. When housed in an enriched environment, MECP2 null mice improved motor abilities and increased levels of BDNF in the brain. We investigated the effects of environmental enrichment on gross motor skills and blood BDNF levels in girls with Rett syndrome.MethodsA genetically variable group of 12 girls with a MECP2 mutation and younger than 6 years participated in a modified individually randomised stepped wedge design study. Assessments were conducted on five occasions, two during the baseline period and three during the intervention period. Gross motor function was assessed using the Rett Syndrome Gross Motor Scale (maximum score of 45) on five occasions, two during the baseline period and three during the intervention period. Blood levels of BDNF were measured at the two baseline assessments and at the end of the intervention period. The intervention comprised motor learning and exercise supplemented with social, cognitive and other sensory experiences over a six-month period.ResultsAt the first assessment, the mean (SD) age of the children was 3 years (1 year 1 month) years ranging from 1 year 6 months to 5 years 2 months. Also at baseline, mean (SD) gross motor scores and blood BDNF levels were 22.7/45 (9.6) and 165.0 (28.8) ng/ml respectively. Adjusting for covariates, the enriched environment was associated with improved gross motor skills (coefficient 8.2, 95%CI 5.1, 11.2) and a 321.4 ng/ml (95%CI 272.0, 370.8) increase in blood BDNF levels after 6 months of treatment. Growth, sleep quality and mood were unaffected.ConclusionsBehavioural interventions such as environmental enrichment can reduce the functional deficit in Rett syndrome, contributing to the evidence-base for management and further understanding of epigenetic mechanisms. Environmental enrichment will be an important adjunct in the evaluation of new drug therapies that use BDNF pathways because of implications for the strengthening of synapses and improved functioning.Trial registrationACTRN12615001286538.

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The mechanism of nonionic surfactants improving the cellulose conversion is still controversial. To protect enzyme stability and prevent unproductive adsorption of cellulase to lignin, which have been thought of as the chief factors for the improvement of nonionic surfactants on cellulolytic hydrolysis, were evaluated in this work. SDS-PAGE detection showed that the enzyme could not aggregate in the enzymatic hydrolysis process whether the polysorbates (Tweens) were present or not. Tweens had different capabilities to retain and even improve enzymes' activities, but these capabilities had little relation to enhancing the enzymatic hydrolysis of treated sugar cane bagasse (SCB). Tweens could increase the adsorption of cellulase to lignins and SCB samples, which was different from the current viewpoint that nonionic surfactants could impede the adsorption of cellulase to lignin. After discussion, it was proposed that the nonionic surfactants initially lubricated the access of cellulase to cellulose and subsequently combined with the free chemical groups released from lignin to impede the adsorption of cellulase to lignin with the enzymatic hydrolysis proceeding.