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Alcohol Groups (alcohol + groups)
Selected AbstractsVerbal and Nonverbal Memory in Adults Prenatally Exposed to AlcoholALCOHOLISM, Issue 5 2010Claire D. Coles Background:, Neurocognitive effects of prenatal alcohol exposure in adulthood are not well documented. Questions persist regarding the extent to which there are specific, measurable effects beyond those associated with global ability deficits, whether individuals without the full fetal alcohol syndrome (FAS) demonstrate alcohol-related cognitive impairments, and whether observed memory effects are specific to a particular modality, i.e., verbal vs. visual/spatial domains. Methods:, In this study, verbal and nonverbal selective reminding paradigms were used to assess memory function in 234 young adults (M age: 22.78, SD: 1.79). Alcohol exposure was quantified prenatally. Alcohol groups included: Individuals with physical effects of alcohol exposure (Dysmorphic group, n = 47); Exposed individuals without such effects (n = 74). Contrast groups included: Controls (n = 59) matched for ethnicity, socioeconomic status, and hospital of birth; Special Education contrast group (n = 54) included to control for disability status. Memory outcomes entailed total recall, delayed recall, and measures of encoding and retrieval, and learning over trials as indexed by slope. Results:, Results indicated that Dysmorphic individuals were significantly less efficient in memory performance than Controls on all of the outcomes measured, but they did not differ from those in the Special Education contrast group. The nondysmorphic, alcohol-exposed group was intermediate in their performance, suggesting a continuum of effects of prenatal exposure. Evaluation of the encoding and retrieval aspects of memory performance indicated that learning rather than forgetting accounted for the deficits associated with prenatal alcohol exposure. Finally, no interaction was found between modality of presentation (verbal and nonverbal) and effects of alcohol exposure on memory performance. Conclusion:, These findings indicate that prenatal alcohol exposure is associated with persistent and specific effects on memory performance, and these problems result from less efficient encoding of information across both verbal and nonverbal modalities. Education and training efforts with this clinical group should take these characteristics into account. [source] Properties of phenol,formaldehyde resin modified with organic acid estersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2008Rados, aw Mirski Abstract Properties of liquid and cured phenol,formaldehyde (PF) resin modified with esters were analyzed in this study. Esters with different carbon chain lengths, both in the acid and alcohol groups, were applied in the experiments. It was found that the modification of phenolic resin with applied esters does not deteriorate its pot life at the temperature of 20°C. It results in an increase of its reactivity at higher temperatures, manifested in the shortening of gel time at 130°C and a decrease of activation energy. Results of FTIR tests of polycondensed modified PF resin showed that products of alkali hydrolysis of esters not only catalyze the curing reaction of resin, but also become embedded in its structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Physicochemical Properties of Cellulose Selectively Oxidized with the 2,2,6,6-Tetramethyl-1-Piperidinyl Oxoammonium IonJOURNAL OF FOOD SCIENCE, Issue 5 2007D.S. Suh ABSTRACT:, This study examined the characteristics of the oxidation reaction on the primary alcohol groups in cellulose involving the 2,2,6,6-tetramethyl-1-piperidinyl oxoammonium ion (TEMPO) and determined the optimum conditions for the preparation of oxidized cellulose (OC). The applicability of OC in polysaccharide systems was also investigated. The effects of TEMPO, sodium bromide (NaBr), and temperature on the oxidation reaction time, yield, and selectivity for primary alcohol groups were examined using response surface methodology (RSM). The reaction time decreased with increases in the temperature and the levels of TEMPO and NaBr. The yield increased with the level of NaBr and decreased as the temperature increased. Selectivity increased with the temperature and decreased as the levels of TEMPO and NaBr increased. The optimum levels of TEMPO and NaBr and the optimum temperature for the production of OC were determined as 0.3 mM/100 mM anhydroglucose unit (AGU), 50 mM/100 mM AGU, and 25 °C, respectively. The water and oil binding capacity and viscosity of cellulose increased with oxidation. Wheat starch containing OC exhibited a decreased initial pasting temperature and setback, but increased peak viscosity, gelatinization, and retrogradation enthalpy (,H). The hardness of the wheat starch gel decreased significantly upon the addition of OC. [source] Analysis of alcohols, as dimethylglycine esters, by electrospray ionization tandem mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 3 2001Dr David W. Johnson Abstract Dimethylglycine (DMG) esters are new derivatives for the rapid, sensitive and selective analysis of primary and secondary alcohols, in complex mixtures, by electrospray ionization tandem mass spectrometry (ESI-MS/MS). Their development was inspired by the use of the complementary dimethylaminoethyl esters for the trace, rapid analysis of fatty acids. DMG esters are simply prepared by heating a dichloromethane solution of the imidazolide of dimethylglycine, containing triethylamine, and an alcohol. DMG esters of long-chain fatty alcohols, isoprenoidal alcohols and hydroxy-acids are analysed by electrospray ionization tandem mass spectrometry with a precursor ion of m/z 104 scan. Diols, glyceryl esters, glyceryl ethers and some sterols are analysed by a neutral loss of 103 Da scan. Trimethylglycine (TMG) ester iodides, prepared by alkylation of DMG esters with methyl iodide, are more sensitive derivatives for molecules containing secondary alcohol groups, such as cholesterol and gibberellic acid. They are analysed by a precursor ion of m/z 118 scan. DMG or TMG derivatives were shown to be at least comparable and sometimes an order of magnitude more sensitive than N -methylpyridyl ether derivatives for ESI-MS/MS analysis of the different classes of alcohols. Applications of these derivatives for the diagnosis of inherited disorders and the analysis of natural products are presented. Copyright © 2001 John Wiley & Sons, Ltd. [source] Preparation and Characterization of Microwave-treated Carboxymethyl Chitin and Carboxymethyl Chitosan Films for Potential Use in Wound Care ApplicationMACROMOLECULAR BIOSCIENCE, Issue 10 2005Panya Wongpanit Abstract Summary: CM-chitin and CM-chitosan films were successfully crosslinked by microwave treatment. Crosslinking of the microwave-treated CM-chitin films involved mainly the carboxylate and the secondary alcohol groups, while crosslinking of microwave-treated CM-chitosan films involved the carboxylate and the amino groups. In addition, the crystallinity of CM-chitin increased with increasing microwave treatment time, whereas an increase in the crystallinity of the microwave-treated CM-chitosan films was not observed. At a similar percentage of weight loss, the crosslinking of either CM-chitin or CM-chitosan films by microwave treatment required much less stringent condition when compared with the crosslinking by autoclave treatment. Based on both direct and indirect cytotoxicity assays, the cytotoxicity of the microwave-treated CM-chitin films was negative, while that of the microwave-treated CM-chitosan films was positive. Human fibroblasts adhered on the surface of microwave-treated CM-chitosan films much better than on the surface of microwave-treated CM-chitin films. Total amount of protein synthesis of living NHGF cells that were cultured on chitin, microwave-treated CM-chitin, chitosan, microwave-treated CM-chitosan films. [source] Direct Synthesis of PVA- g -PDMS in MicrosuspensionMACROMOLECULAR RAPID COMMUNICATIONS, Issue 5 2008Emmanuel Pouget Abstract The synthesis of P(VA- co -VAc)- graft -PDMS copolymers has been achieved in microsuspension by direct reaction between an epoxy-terminated PDMS and some pendant alcohol groups in P(VA- co -VAc). In this synthesis, the copolymer is used both as dispersant and reactant. The hydrophilic/hydrophobic character of the final material can be varied at will by incorporating various contents of epoxy-functionalized PDMS through optimized reaction conditions. The final composition was determined by TGA and 1H NMR. Products prepared from monofunctional PDMS were easily redispersed in water whereas a film of crosslinked materials, arising from difunctional PDMS, showed the best waterproofing as shown by contact angle analysis. [source] Ceric Ammonium Nitrate Initiated Grafting of PEG to Plasma Polymers for Cell-Resistant SurfacesPLASMA PROCESSES AND POLYMERS, Issue 2 2008Naomi J. Vickers Abstract The development of a facile method with general applicability and mild reaction conditions for grafting PEG onto surfaces to reduce bio-adhesion is described. The approach taken was to use CAN to graft PEG to plasma polymers coatings selected to give a high concentration of alcohol groups. The study showed that grafting required functional groups on surfaces, a minimum concentration of CAN initiator (0.05 M) and was time and initiator concentration dependent. Adhesion of fibroblasts and endothelial cells was reduced to negligible levels compared to the adhesion to tissue culture polystyrene and untreated plasma polymers of allyl alcohol following CAN induced PEG grafting. [source] Hydrogen-bonded networks in 1-(4-methoxyphenyl)-2,2-dimethylpropan-1-olACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2007Marek Gli The asymmetric unit of the title compound, C12H18O2, contains two independent molecules. They differ only slightly in conformation but form completely different intermolecular hydrogen-bonded arrays. One molecule exhibits disorder in the hydroxy group region, but this does not influence the formation of hydrogen bonds. The bulky tert -butyl group on one side of the carbinol C atom and the benzene ring on the other side promote the formation of discrete dimeric motifs via hydrogen-bridged hydroxy groups. Dimers are further joined by strong hydroxy,methoxy O,H...O bonds to form chains with dangling alcohol groups. Weaker intermolecular C,H...O interactions mediate the formation of a two-dimensional network. [source] Gold Catalysis: Tandem Reactions of Diyne,Diols and External Nucleophiles as an Easy Access to Tricyclic Cage-Like Structures,CHEMISTRY - A EUROPEAN JOURNAL, Issue 32 2010Stephen Abstract Different diyne,diols composed of two terminal homopropargylic alcohol groups were prepared by bi-directional synthesis. Subjection of the syn diastereomers to NAC,gold catalysts (NAC=nitrogen acyclic carbene) in the presence of external nucleophiles such as water or anilines provided substituted and highly rigid heterocyclic cages. The corresponding anti disastereomers polymerised. An intermediate of the reactions of the syn diastereomers could be isolated and even be characterised by crystal structure analysis. Overall, eight new bonds are formed in the reaction, which proceeds by a multistep sequence of highly selective hydroalkoxylations and hydrohydroxylation or hydroaminations. For furyl substituents and for internal alkynes competing reaction pathways could be identified. By the cross-coupling of a product with an iodoaryl substituent, the use of these cage compounds as geometrically defined linking groups by using orthogonal transition-metal-catalysed methodology, namely, gold and palladium catalysis, could be demonstrated. [source] | |||||||||||||