GUIDELINES FOR DESIGNING EIS INTERFACES Meeting Executives' Information Needs

For users of an executive information system (EIS), the EIS interface is the system and is crucial to the EIS's success. These guidelines for designing EIS interfaces are based on studies of actual EIS interfaces that meet the unique information needs of executives.     

Organic Materials and Thin‐Film Structures for Cross‐Point Memory Cells Based on Trapping in Metallic Nanoparticles

Non‐volatile solid‐state memory cells based on composites of metal nanoparticles and polymers are embedded in organic semiconducting host materials. This paper presents data from a wide range of materials and device structures and shows that the switching phenomenon is commonly observed.     

Intrinsic Volume Changes of Self-propagating Synthesis

The final product(s) of self-propagating synthesis are shown to be intrinsically denser than the starting reactants. This behavior results in intrinsic decreases in the sample volume that increase with both the heat of reaction and the adiabatic combustion temperature. Forming of liquid product(s) during reaction simply adds another intrinsic source of porosity, i.e. changes in volume on product solidification. Thus, obtaining fully dense bodies from self-propagating synthesis requires a mechanism for reducing porosity, e.g. hot-pressing.     

Luminescence from praseodymium doped AlN thin films deposited by RF magnetron sputtering and the effect of material structure and thermal annealing on the luminescence

Thin films of Praseodymium doped AlN are deposited on silicon (111) substrates at 77 K and 950 K by rf magnetron sputtering method. About 500–1000 nm thick films are grown at 100–200 watts RF power and 5–8 mTorr nitrogen, using a metal target of Al with Pr. X-rays diffraction results show that films deposited at 77 K are amorphous and those deposited at 950 K are crystalline. Cathodoluminescence studies are performed at room temperature and luminescence peaks are observed in a wide range from ultraviolet to infrared region. The most intense peak is obtained in green at 526 nm from amorphous films as a result from ³P₁→³H₅ transition. In crystalline films the intense peak was obtain in red at 648 nm as a result from ³P₀→³F₂ transition. Films are thermally activated at 1300 K for half an hour in a nitrogen atmosphere. Thermal activation enhances the intensity of luminescence. Two peaks at 488 nm and 505 nm merged after thermal activation, giving rise to a single peak at 495 nm.     

Effect of postnatal exposure to a PCB mixture in monkeys on multiple fixed interval-fixed ratio performance

Behavioral impairment as a consequence of PCB exposure beginning in utero has been reported in both humans and animals. The present study assessed the behavioral consequences of postnatal exposure to PCBs. Male monkeys (Macaca fascicularis) were dosed from birth to 20 weeks of age with 7.5 microgram(s)/kg/day of a PCB mixture representative of the PCBs typically found in human breast milk (eight monkeys) or vehicle (four monkeys). At 4 years of age, performance under a multiple fixed interval (FI)-fixed ratio (FR) schedule of reinforcement was assessed. The FI component was more sensitive to disruption as a result of PCB exposure than was the FR component. PCB-exposed monkeys displayed shorter mean interresponse times (IRTs) than controls, particularly during the earlier sessions of the experiment. Similarly, the increase in pause time characteristic of the acquisition of typical FI performance emerged more slowly across sessions in the PCB-treated group. However, the number of short IRTs (less than 5 s) remained greater in the treated group compared to controls over the 48-session duration of the experiment. On the FR component, control monkeys decreases the mean pause time across sessions whereas the PCB-treated group did not; there were no differences between groups for absolute value of average IRT or pause time. The results of this study extend previous research in this cohort of monkeys, and provide further evidence that PCB exposure limited to the early postnatal period and resulting in environmentally relevant body burdens produces long-term behavioral effects.     

Concentration-response relationships for adenosine agonists during preconditioning of rabbit cardiomyocytes

Although adenosine receptors have been implicated in the induction of preconditioning in a variety of experimental models, there is controversy concerning the specific adenosine receptor subtypes mediating this effect. Concentration-protection relationships for adenosine and adenosine agonists in rabbit cardiomyocytes were used to characterize the role of adenosine receptor subtypes in preconditioning. Isolated cells were ischemically preconditioned or pre-incubated for 10 min with increasing concentrations of adenosine, CCPA (2-chloro-N6-cyclopentyladenosine), APNEA (N6-2-(4-aminophenyl)ethyladenosine), or BNECA (N6-benzyl-5'-N-ethyl-carboxamidoadenosine) in the presence or absence of 1 or 10 microM of the selective A1-adenosine antagonist DPCPX (8-Cyclopentyl-1,3-dipropylxanthine). Following a 30-min post-incubation period, cells were pelleted, layered with oil and ischemically incubated for 180 min. Injury was assessed by osmotic swelling and trypan blue exclusion of sequential samples, and determination of the areas beneath the mortality curves. Adenosine produced a broad concentration-protection curve which was displaced to the right by DPCPX. The curve for A1-selective agonist CCPA was biphasic, with an initial response below 1 nM and a second above 1 microM. DPCPX abolished the early response leaving a steep monophasic curve between 0.1 and 10 microM CCPA. The APNEA curve appeared moriophasic, the major slope occurring between 1-100 nM; DPCPX (1 microM) shifted the concentration-response curve approximately 30-fold and decreased the slope. Adenosine receptor agonist BNECA produced preconditioning characterized by a shallow monophasic concentration-protection curve with a maximal effect of 49% and an EC50 of approximately 5 nM; DPCPX shifted the BNECA concentration-protection relationship approximately 40-fold with only a modest increase in slope. Analysis of the data suggests that induction of preconditioning results from interaction of agonists with the A1 receptor and a second adenosine receptor having properties consistent with the A3 receptor. Adenosine, CCPA, APNEA, BNECA and DPCPX each appear to be selective for the A1 adenosine receptor subtype in isolated rabbit cardiomyocytes.     

Comparison of physical property-porosity behaviour with minimum solid area models

An extensive survey of the porosity dependence of (room temperature) physical properties shows that mechanical properties and electrical and thermal conductivity, i.e. properties dependent on the local flux or fields in the material, follow minimum solid area models. This is shown extensively for elastic properties and tensile (flexure) strength, but consistency with other properties, e.g. compressive strength, hardness, electrical and thermal conductivity is also shown. Although data for ceramics is most extensive, data for rocks, metals, and carbon are included, since the consistency of these, especially of metals with ceramics, provides important support for the minimum solid area concept. While porosity characterization is generally minimal, expected model trends with pore character are corroborated by correlating processing and resultant expected pore character with porosity-property results. It is argued that properties dependent on mass should be better fit by a linear, i.e. rule of mixture, relationship between such properties and porosity. Support for this is shown in dielectric constant-porosity data.