Aromatic Hydrogenation Catalysis: A Review

High aromatic content in diesel fuel has been recognized both to lower the fuel quality and to contribute significantly to the formation of undesired emissions in exhaust gases [1, 2]. Because of the health hazards associated with these emissions, environmental regulations governing the composition of diesel fuels are being tightened in both Europe and the United States, leading to limitations on aromatics [3, 4].     

Complexity and computability of solutions to linear programming systems

Through key examples and constructs, exact and approximate, complexity, computability, and solution of linear programming systems are reexamined in the light of Khachian's new notion of (approximate) solution. Algorithms, basic theorems, and alternate representations are reviewed. It is shown that the Klee-Minty example hasnever been exponential for (exact) adjacent extreme point algorithms and that the Balinski-Gomory (exact) algorithm continues to be polynomial in cases where (approximate) ellipsoidal centered-cutoff algorithms (Levin, Shor, Khachian, Gacs-Lovasz) are exponential. By model approximation, both the Klee-Minty and the new J. Clausen examples are shown to be trivial (explicitly solvable) interval programming problems. A new notion of computable (approximate) solution is proposed together with ana priori regularization for linear programming systems. New polyhedral constraint contraction algorithms are proposed for approximate solution and the relevance of interval programming for good starts or exact solution is brought forth. It is concluded from all this that the imposed problem ignorance of past complexity research is deleterious to research progress on computability or efficiency of computation.This research was partly supported by Project NR047-071, ONR Contract N00014-80-C-0242, and Project NR047-021, ONR Contract N00014-75-C-0569, with the Center for Cybernetic Studies, The University of Texas at Austin.     

The effect of synchronization on the interpretation of flashing lamp displays

The question of whether all the lamps on a display indicating the same state should flash in phase with each other or independently is of interest to display designers. A randomized groups experiment was carried out to answer this question. It was found that a synchronized display was interpreted more quickly and with fewer errors than a display with independently flashing lamps.     

Subjective time experience in an intergenerational sample

The roles chronological age and gender play in subjective time experience were explored in a sample of 294 adult men and women. Subjective time experience (STE: the difference between subjective age and chronological age) was found to vary widely among individuals, with some being "accurate" (SA = CA), and others either "retarded" (SA less than CA) or "advanced" (SA greater than CA). Males were more retarded in STE than females at every point in the lifespan, and patterns of age differences in adulthood differed for the two sexes as well. The results suggest that chronological age may play a key role in transitions in STE, and that chronological age is more significant in the STE of women than in the STE of men.     

The effect of feedback on keying performance

The introduction of new telephone signalling systems and new technologies for telephone keypads has stimulated interest in the effect of providing electronic feedback on keying performance. An experiment using a conventional keypad is reported which shows that electronic auditory feedback had no significant effect on keying speed, accuracy or subject's opinion. A further series of experiments investigating the best type of feedback to improve performance with ‘touch’ keypads is then described. It was found that an electronic tone presented through the telephone earpiece was the best feedback.

Finally, performance with two types of touch keyphones incorporating the optimum form of feedback was compared with performance using a conventional keyphone. It was found that accuracy was significantly greater with the conventional keyphone, although performance with the touch keypads could be improved by electronically removing some of the very short spurious signalling times produced by them.     

A sensitive method for the determination of amitriptyline and nortriptyline in human plasma

The kinetics of the male gametogenesis during the pregonadal period, prespermatogenesis, and "early" spermatogenesis has been described in detail. Concerning spermatogenesis in the adult individual reference is made to the articles of Courot, Hochereau-de Reviers and Ortavant (1970) and of Clermont (1972). The comparison of female and male gametogenesis (Fig. 1) shows that the "gonia stage" (asterisks) of the female germ cells is limited to one proliferation wave only, whereas the "gonia stage" of the male germ cells consists of a first proliferation wave, comparable to that of oogonia, a preparative phase to initiate spermatogenesis, and a second proliferation wave with renewal and differentiation of the spermatogonia. Germ cells in the "gonia stage" are highly sensitive towards ionising radiation and cytostatic drugs.     

Family centered maternity care: its relationship to perinatal regionalization and neonatal intensive care

For several months prior to birth a major portion of a family's attention, conversation, thought, and often worry, is directed toward the idea of a new child. This prolonged attention and anticipation contribute to making childbirth an emotionally charged experience. In psychological terms, it is therefore a critical period of peak motivation for learning, and a time to peak susceptibility to reinforcement. Theory, reason, and scientific evidence indicate thng with childbirth and early postpartum experiences, can significantly affect subsequent parental behaviors, the child's central environment influence. Evidence strongly suggests that these parental attitudes and behaviors so crucial to the child's ultimate well-being are learned rather than derived instinctually, and therefore they are malleable and can be taught, directed, and corrected. Through education and reinforcement it is possible to encourage parental behaviors and child interactions which are products of feelings of control, competence, accomplishment, understanding, and caring. Similarly we can recognize and work toward replacing attitudes, feelings, and behaviors that express fear, worry, and insecurity about the child. Over the past 50 years major changes have occurred in the practice of obstetrics and newborn pediatrics. Other major changes will necessarily occur as we move toward perinatal regionalization. Changes instigated solely on physiologic data can have unrecognized collateral effects on the psychological component of the childbirth experience. All concerned health care personnel, especially obstetricians and pediatricians, can insist that the importance of desirable mother-father-child interactions be recognized and that practices fostering them be afforded a high priority. I would like to endorse a comment from a recent article by Richmond concerning the advent of behavioral pediatrics by adding that behavioral obstetrics is also "an idea whose time has arrived".     

Race and IQ: Molecular Genetics as Deus ex Machina.

During the last hundred years, the debate over the meaning of race has retained a highly consistent core, despite evolution of the technical details. Non-Europeans, and in particular, Africans, are assigned the role of deviants and outcasts, whose claim on our common humanity remains in doubt. Each time the technical facade of these racialist arguments is destroyed, the latest jargon and half-truths from the margins of science are used to rebuild them around the same core belief in Black inferiority. Because race is in part a genetic concept, the advent of molecular DNA technology has opened an important new chapter in this story. Unfortunately, the article by D. Rowe (2005, this issue, see record 2005-00117-007) begins from mistaken premises and merely restates the racialist view using the terminology of molecular genetics. No technology--even the awe-inspiring tools now available to DNA science--can overcome the handicap of fundamental conceptual errors. Race is not a concept that emerged from within modern genetics; rather, it was imposed by history, and its meaning is inseparable from that cultural origin. By ignoring its cultural meaning the reductionist narrative about race fails--both in the narrow terms of science and as a contribution to the broader social discourse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of a Position Sensitive Neutron Detector with High Efficiency and Energy Resolution for Use at High-Flux Beam Sources

We are developing a high-efficiency neutron detector with 1 cm position resolution and coarse energy resolution for use at high-flux neutron source facilities currently proposed or under construction. The detector concept integrates a segmented ³He ionization chamber with the position sensitive, charged particle collection methods of a MicroMegas detector. Neutron absorption on the helium produces protons and tritons that ionize the fill gas. The charge is amplified in the field region around a wire mesh and subsequently detected in current mode by wire strips mounted on a substrate. One module consisting of a high-voltage plate, a field-shaping high-voltage plate, a grid and wire strips defines a detection region. For 100 % efficiency, detector modules are consecutively placed along the beam axis. Analysis over several regions with alternating wire strip orientation provides a two-dimensional beam profile. By using ³He, a 1/v absorption gas, each axial region captures neutrons of a different energy range, providing an energy-sensitive detection scheme especially useful at continuous beam sources.     

Life-cycle modeling for adaptive and variant design. Part 1: Methodology

Life-cycle modeling for design (LCMD) is a methodology for assessing the life-cycle impacts for a complex product with many individual components starting from initial design phases when few design specifications have been made. The methodology combines life-cycle assessment (LCA) with probabilistic design methods in a way that forecasts attributes of possible final designs yet reduces information needs. Specifically, LCMD is a methodology for generating arrays of design scenarios that communicate the range of designs being considered by a design team, and estimating missing data for those design scenarios. The main contribution to enhancing standard LCA is the incorporation of methods to estimate physical attributes of individual components for various design options and in four analyses for evaluating the arrays of design scenarios. An automotive case study presented in part 2 of this work demonstrates one application of LCMD.