The heterogeneous character of the dilute acid hydrolysis of crystalline cellulose. III. Kinetic and X-ray data

Thirteen prehydrolyzed samples of cellulose, including native, mercerized, and regenerated materials were hydrolyzed in 1% and 1.5% sulfuric acid at 160, 170, and 180°C. Pseudo first-order rate constants and weight average degrees of polymerization were determined for each sample. For all cellulose samples, data from several experiments were used to determine the dependence of the rate of hydrolysis on sulfuric acid concentration. The results obtained in this study indicate that Sharples' end-attack model is consistent with kinetic data for the hydrolysis of cellulose II samples, but is not applicable to the hydrolysis of cellulose I samples. X-ray diffraction analyses indicated that, for native and mercerized cellulose samples, structural changes during dilute acid hydrolysis are not significant. However, data for rayon indicated that such changes may need to be taken into account in analysis of the reaction kinetics.     

Comparison of the K--BIT with short forms of the WAIS--R in a neuropsychological population.

The purpose of the study was to compare the Kaufman Brief Intelligence Test (K-BIT; A. S. Kaufman & N. L. Kaufman, 1990) with subtest reduction short forms of the Wechsler Adult Intelligence Scale--Revised (WAIS--R; D. Wechsler, 1976) and Full Scale WAIS--R scores (FSIQ). The participants were 64 consecutive referrals to a neuropsychology service. Results indicated that the K-BIT did well but not as well as the WAIS--R short forms in predicting FSIQ. The K-BIT has the advantage that it is motor free and takes only 15 to 30 min. The WAIS--R short form procedures have the advantage that, should there be a need for a complete WAIS--R profile, the nonadministered subtests could be added at a later date. The WAIS--R is also more familiar to many clinicians. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note on boundingk-terminal reliability

A generalization of a theorem of Lomonosov and Polesskii is proved, which provides a novel method for determining upper bounds on the probability that a graph contains a Steiner tree (k-terminal reliability).     

OEICs for WDM transceiver modules fabricated by reactive ion etching on semi-insulating substrates

The design and fabrication of OEICs on semi-insulating InP substrates comprising 1300 nm DFB lasers, 1300/1530 nm wavelength duplexers and monitor photodiodes is described. OEIC lasing thresholds were as low as 20 mA. The through-state crosstalk for the integrated duplexer was typically -12 dB. Linear tracking of the laser output by the monitor photodiode was achieved with sensitivities in the region of 70 mu A/mW. The OEICs operated successfully in a 622 Mbit/s bidirectional optical link.<>     

Photopolymerization of an expanding monomer with an aromatic dioxirane

The objective was to study the photocationic polymerization of an expanding monomer, 1,5,7,11‐tetraoxaspiro[5.5]undecane (TOSU), and an aromatic dioxirane, bisphenol A diglycidyl ether (BADGE). Both homopolymerizations and binary polymerizations were conducted. The homopolymer, poly(TOSU), was found to be a linear poly(carbonate), which was soluble in acetone. Poly(BADGE) products contained ether linkages in addition to primary and secondary alcohol functionalities. Binary polymerization products varied depending on the irradiation time and length of dark cure. ¹³C‐NMR analysis of binary polymerizate products revealed peaks not seen in homopolymer spectra consistent with the formation of copolymer linkages. Mass spectrometry data revealed peaks consistent with oligomers that contained both TOSU and BADGE mer units. The structures of key reaction products were proposed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 62–71, 2004     

Age differences in trust and reliance of a medication management system

The present study examined age differences in trust and reliance of an automated decision aid. In Experiment 1, older and younger participants performed a simple mathematical task concurrent with a simulated medication management task. The decision aid was designed to facilitate medication management, but with varying reliability. Trust, self-confidence and usage of the aid were measured. The results indicated that older adults had greater trust in the aid and were less confident in their performance, but they did not calibrate trust differently than younger adults. In Experiment 2, a variant of the same task was used to investigate whether older adults are subject to over-reliance on the automation. Differences in omission and commission errors were examined. The results indicated that older adults were more reliant on the decision aid and committed more automation-related errors. A signal detection analyses indicated that older adults were less sensitive to automation failures. Results are discussed with respect to the perceptual and cognitive factors that influence age differences in the use of fallible automation.     

Massage therapy in the treatment of lymphedema. Rationale, results, and applications.

The ongoing NCCAM-supported experimental and clinical translational approaches should shed light not only on the physiologic mechanisms underlying the benefits of massage therapy but could also, if successful in defined populations of patients, have a substantial impact by providing a simpler, more cost-effective LE treatment alternative worldwide.     

Young children's predictions of illness: Failure to recognize probabilistic causation.

In this study preschool-age children made predictions for a set of salient probabilistic causes. Of interest was whether the children viewed outcomes of familiar causes of illness as definite or as probabilistic. In Experiment 1, children judged that a common cause would affect all members of a group in the same way. In Experiment 2, children believed they could definitely predict illness outcomes in a single case. These judgments contrasted with adults' variable and uncertain predictions. Children did recognize uncertainty in outcomes dependent on voluntary choices. Experiment 3 presented both high- and low-potency causes of illness. Children treated all causes of illness as nonprobabilistic. These results are discussed in the context of children's understanding of causal relations and the sources of variability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of gigabit network research on scientific visualization

Networks based on the High Performance Parallel Interface (HIPPI) will become the norm at Los Alamos National Laboratory. The ramification of such a high-speed networking paradigm on scientific visualization are enormous. Not only will scientists have the capability of networked framebuffer animation loops in their offices, but also the partitioning of graphics tasks between MIMD, SIMD, and specialized hardware will be feasible. Of course, as bandwidth increases, the problem size quickly grows to exceed whatever the limits are. For this reason, the investigation of gigabyte networks is currently underway at Los Alamos National Laboratory.