Information Systems in Transition Economies: Does Ownership Matter?

This research investigates the moderating roles of firm ownership in managerial perceptions of information systems (IS) in transition economies. Analysis of representative survey data from 304 companies in Hungary showed that perceptions of IS are driven by organizational variables in foreign firms, and by environmental variables in domestic firms. The findings embrace a more fine-grained notion of variables affecting IS usefulness in the transition economy context by showing that those are contingent on firm ownership.     

Environmental and human factors influencing thermal comfort of office occupants in hot - humid and hot - arid climates

The effects of environmental and individual factors on thermal sensation in air-conditioned office environments were analysed for two large, fully compatible thermal comfort field studies in contrasting Australian climates. In the hot - humid location of Townsville, 836 office workers were surveyed; 935 workers participated in hot - arid Kalgoorlie-Boulder. Overall perceived work area temperature and measured indoor operative temperature correlated moderately with thermal sensation for Townsville (T) subjects but only perceived temperature correlated with Kalgoorlie-Boulder (KB) sensation. Multiple regression analyses confirmed that indoor climatic variables (including Predicted Mean Vote) contributed to actual thermal sensation vote (24% T; 15% KB), with operative temperature having more of an effect in T than in KB. Subsequent analyses of individual characteristics showed no linear contributions to thermal sensation. The remaining variances were significantly related to perceived work area temperature (7% additional explained variance in T; 12% in KB). Mann - Whitney analyses (after correction for climatic variables) showed that T subjects with higher job satisfaction had thermal sensations closer to 'neutral'. Males, healthier subjects, non-smokers, respondents with earlier survey times and underweight occupants had lower median thermal sensations in KB. Townsville occupants appeared more adapted to their outdoor climatic conditions than Kalgoorlie-Boulder respondents, perhaps due to limited home air-conditioning. Further research into non-thermal impacts on gender-related thermal acceptability is suggested.     

Self-assessment and task selection in learner-controlled instruction: Differences between effective and ineffective learners

Learner-controlled instruction is often found to be less effective for learning than fixed or adaptive system-controlled instruction. One possible reason for that finding is that students – especially novices – might not able to accurately assess their own performance and select tasks that fit their learning needs. Therefore, this explorative study investigated the differences in self-assessment and task-selection processes between effective and ineffective learners (i.e., in terms of learning gains) studying in a learner-controlled instructional environment. Results indicated that although effective learners could more accurately assess their own performance than ineffective learners, they used the same task aspects to select learning tasks. For effective learners, who were also more accurate self-assessors, the self-assessment criteria predicted subsequent task selection. The results are discussed, particularly with regard to their potential to provide guidelines for the design of a self-assessment and task-selection training.     

Binding of the tautomeric forms of isoniazid-NAD adducts to the active site of the Mycobacterium tuberculosis enoyl-ACP reductase (InhA): a theoretical approach

The front-line antituberculosis drug isoniazid (INH) inhibits InhA, the NADH-dependent fatty acid biosynthesis enoyl ACP-reductase from Mycobacterium tuberculosis, via formation of covalent adducts with NAD (INH-NAD adducts). While ring tautomers were found the main species formed in solution, only the 4S chain INH-NAD tautomer was evidenced in the crystallized InhA:INH-NAD complex. In this study we attempted to explore the modes of interaction and energy binding of the different isomers placed in the active site of InhA with the help of various molecular modelling techniques. Ligand and enzyme models were generated with the help of the Vega ZZ program package. Resulting ligands were then docked into the InhA active site individually using computational automated docking package AUTODOCK 3.0.5. The more relevant docked conformations were then used to compute the interaction energy between the ligands and the InhA cavity. The AM1 Hamiltonian and the QM/MM ONIOM methodologies were used and the results compared. The various tautomers were found docked in almost the same place where INH-NAD was present as predicted by earlier X-ray crystallographic studies. However, some changes of ligand conformation and of the interactions ligand-protein were evidenced. The lower binding energy was observed for the 4S chain adduct that probably represents the effective active form of the INH-NAD adducts, as compared to the 4R epimer. The two 4S,7R and 4R,7S ring tautomers show intermediate and similar binding energies contrasting with their different experimental inhibitory potency on InhA. As a possible explanation based on calculated conformations, we formulated the hypothesis of an initial binding of the two ring tautomers to InhA followed by opening of only the ring hemiamidal 4S,7R tautomer (possibly catalyzed by Tyr158 phenolate basic group) to give the 4S chain INH-NAD tight-binding inhibitor. The predictions of ligand-protein interactions at the molecular level can be of primary importance in elucidating the mechanisms of action of isoniazid and InhA-related resistances, in identifying the effective mycobactericidal entities and, in further step, in the design of a new generation of antitubercular drugs.     

Smashing peacocks further: drawing quasi-trees from biconnected components

We extend the popular force-directed approach to network (or graph) layout to allow separation constraints, which enforce a minimum horizontal or vertical separation between selected pairs of nodes. This simple class of linear constraints is expressive enough to satisfy a wide variety of application-specific layout requirements, including: layout of directed graphs to better show flow; layout with non-overlapping node labels; and layout of graphs with grouped nodes (called clusters). In the stress majorization force-directed layout process, separation constraints can be treated as a quadratic programming problem. We give an incremental algorithm based on gradient projection for efficiently solving this problem. The algorithm is considerably faster than using generic constraint optimization techniques and is comparable in speed to unconstrained stress majorization. We demonstrate the utility of our technique with sample data from a number of practical applications including gene-activation networks, terrorist networks and visualization of high-dimensional data     

Using informal notes for sharing corporate technology know-how

Corporate and academic communities have focused a great deal of attention on formalized approaches for creating, capturing, and propagating knowledge. Far less attention has been paid to the informal mechanisms that individuals share and employ to help them navigate complex processes in order to ‘get things done.’ In this paper, we examine the creation, use, and content of informal documents for supporting users of an enterprise resource planning system in a Fortune 500 company. We contend that such notes, which are commonly used for supporting information systems-related work, are an overlooked source of knowledgeability about organizational practices. This study is a first but necessary step in analyzing the types of information that can be derived from informal notes so that organizations can more fully utilize this largely untapped resource.     

Marital conflict and endocrine function: Are men really more physiologically affected than women?

This study assessed marital conflict behavior and endocrine function in 90 newlywed couples. Blood samples acquired hourly from 8:00 a.m. through 10:00 p.m. were combined to provide composite daytime values for 3 stress hormones--epinephrine ( EPI ), norepinephrine ( NEPI ), and cortisol -- and 3 related hormones (ACTH, growth hormone, and prolactin). These pooled data provided a window on endocrine function in couples for whom the day included a conflict. For wives, higher probabilities of husband's withdrawal in response to wife's negative behavior were associated with higher NEPI and cortisol levels. In addition, higher frequencies of positive behaviors were associated with lower EPI and higher prolactin levels among wives. Husbands' endocrine data were not associated with behavioral data. These findings are discussed in the context of gender models of marital conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fischer–Tropsch synthesis using plug-through contactor membranes based on permeable composite monoliths. Selectivity control by porous structure parameters and membrane geometry

The Fischer–Tropsch synthesis using a contactor membrane reactor was studied varying pore size distribution parameters and membrane geometry. These parameters are responsible for the magnitude of the diffusion constrains and, therefore, correlate with the FTS process productivity and selectivity. The nature of the observed correlations is discussed.     

Behavioral sensitization to drug stimulant effects in C57BL/6J and DBA/2J inbred mice.

Common features shared by addictive drugs have been difficult to identify. One ubiquitous effect of these drugs is psychomotor stimulation. Further, repeated exposure commonly results in sensitization to drug stimulant effects. This study evaluates sensitization to drugs from several drug classes in C57BL/6J and DBA/2J inbred strain mice. DBA/2J mice showed sensitized responses to ethanol and methamphetamine, whereas C57BL/6J mice developed sensitization to morphine and methamphetamine. Strain susceptibilities to ethanol- and morphine-induced sensitization closely paralleled their sensitivities to the acute stimulant effects of these drugs; this was not the case for methamphetamine. The relative sensitivities of DBA/2J and C57BL/6J mice were not consistent across drugs, suggesting that the stimulant and sensitized responses to these drugs may be mediated by at least partially divergent neural mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)