Temporal Specificity of Extinction in Autoshaping.

Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Localization of extracellular matrix molecules, integrins and their regulators, TGF betas, is correlated with axon pathfinding in the spinal cord of normal and Danforth''s short tail mice

We present a local Dissemination of EPIC, a project which has been devised to support health and social primary care by an information system. One key point of the EPIC project was a standardization effort at European level, providing a standardized basis for the management system based on client needs for planning and manpower control. Whilst EPIC has been designed as a general community information system, the main EPIC applications focus is on the care of the elderly. Savona is a middle size Italian town with a high percentage of elderly people and has already had an experience of integration of health and social care within an Italian project. It has therefore been regarded as a suitable site for the dissemination of EPIC. The EPIC application solved some of the information problems which emerged during the validation of the previous Italian project, such as the definition of the requirements; the collection, processing and retrieval of the clinical/social data; the definition of responsibilities and relations of the operators.     

Effects of short- and long-term dexamethasone treatment on growth and growth hormone (GH)-releasing hormone (GRH)-GH-insulin-like growth factor-I axis in conscious rats

Although the inhibitory effects of a chronic excess of glucocorticoids (GC) on body growth and GH secretion are well established, the mechanisms involved remain unclear. In this study, we examined the chronic effects of a high dose of dexamethasone (DEX) on spontaneous GH secretion and insulin-like growth factor (IGF)-I in conscious rats. The animals were given daily i.p. injections of DEX (200 microg/day) for either one or four weeks. Body growth assessed by tibia length and serum IGF-I levels was significantly inhibited 1 week after treatment. By contrast, spontaneous GH secretion was not altered 1 week after the treatment. Neither hypothalamic GRH and somtatostain mRNA levels nor GH responses to GRH from single somatotropes were affected 1 week after the treatment. Four weeks after DEX treatment, body growth of the rats was noticeably suppressed. Interestingly, spontaneous GH secretion, hypothalamic GRH mRNA levels and GH responses to GRH were all inhibited 4 weeks after treatment. Pituitary GRH receptor mRNA levels were not altered 1 week after treatment, but increased after 4 weeks. These results indicate that a high dose of DEX initially impairs IGF-I production and subsequently inhibits spontaneous GH secretion in rats. Inhibition of spontaneous GH secretion resulting from chronic GC excess is due, at least in part, to the impairment of hypothalamic GRH synthesis and pituitary GH responsiveness. An increase in the pituitary GRH receptor may be caused by decreased GRH secretion.     

Radiation damage induced in Si photodiodes by high-temperature neutron irradiation

Results are presented of a detailed study of the effects of high-temperature 4-MeV neutron irradiation on the performance degradation of Si pin photodiodes together with the radiation-induced defects, observed by deep level transient spectroscopy (DLTS). It was found that the dark current increases after irradiation, while the photocurrent decreases. After irradiation, two majority electron capture levels with (E _c–0.22 eV) and (E _c–0.40 eV) were induced in the n-Si substrate, while one minority hole capture level with (E _v+0.37 eV) was found. Additionally, the degradation of the device performance and the introduction rate of the lattice defects decreases with increasing irradiation temperature. For a 250 °C irradiation, the reduction of the reverse current is only 20% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures.     

Syntheses and structural properties of four Rb-aluminosilicate zeolites

Four types of Rb-aluminosilicate zeolites were hydrothermally synthesized in pure phase for the first time from Rb-aluminosilicate gels without using any organic structure-directing agent (SDA) under stirring conditions. The crystal structure of each zeolite was refined by Rietveld analysis of the X-ray diffraction (XRD) data. These crystal structures were confirmed to be Rb-mordenite, Rb-merlinoite, a new aluminosilicate zeolite with an ATT framework topology, and Rb-offretite denoted by RMA-1, RMA-2, RMA-3, and RMA-4, respectively. The Si/Al ratio of RMA-1 with an MOR topology varied from 5.3 to 8.0; however, the variation of the Si/Al ratios of the other zeolites was rather small. The crystal system of RMA-2 was tetragonal with space group I4/mmm, where two Rb sites were distributed at the center of an 8-membered ring (MR). On the other hand, two Rb sites in RMA-3 were located at the center of the 8-MR in small two cages. The structure of RMA-4 was identified as the OFF type with a local disorder or defect, which included a small amount of an intergrown ERI phase.     

Identification of an endonuclease responsible for apoptosis in rat thymocytes

We studied total occlusion of all three coronary arteries. From 1975 to 1992, a total of 4,100 patients underwent coronary arteriography at Show University Hospital. Of these, four patients (0.1%) had complete occlusion of all three coronary arteries and all of them underwent coronary artery bypass grafting (CABG). The mean numbers of coronary risk factors were only 2.3 but history of angina of effort were long-standing such as 4 to 29 years (mean 16.3 yr). All cases had previous episodes of myocardial infarction. Three cases (75%) had aortic aneurysm. One case was also diagnosed as Leriche syndrome besides coexisting aneurysm. Coronary arteriogram showed total occlusion of right coronary artery, left anterior descending artery and left circumflex artery in the segment of 1.6 or 7 and 11 respectively. All cases had intracoronary anastomosis and intercoronary anastomosis. Among 12 occluded coronary arteries of all four cases, 11 were distally visualized with contrast medium via collateral flow but good opacification of the distal coronary trees were not seen. Also proper assessments of cardiac performance including viability of myocardium were not established because all cases were in the state of C.C.S grades IV. But significant clinical recovery were obtained in all cases after CAGB of three or four bypass. We conclude that these results might be a useful suggestion for the treatment of total occlusion of all three coronary arteries.     

A PRACTICAL METHOD FOR RECTIFYING INTERFACIAL TENSION DATA TO PREDICT THE SHAPE OF INTERFACES IN AN IMMISCIBLE LIQUID/LIQUID/GAS SYSTEM

The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems.     

The distribution of soap in the polymerization system for preparation of carboxylated polystyrene latexes

The distribution of soap in the polymerization system for preparation of carboxylated polystyrene latexes has been investigated. The critical micelle concentration (CMC) for sodium dodecyl sulfate (SDS) in the polymerization system was determined by surface tension measurement to be 0.173 mmole/l. The solubility of styrene (St) in the aqueous phase of the polymerization system was determined by NMR measurement to be 4.52 mmole/l. It was confirmed by NMR measurement that at the concentration of SDS higher than the CMC, St is solubilized in the interior of the SDS micelles, and the concentration of solubilized St is almost proportional to the concentration of micellar SDS. From this relationship, the number and radius of SDS micelles containing solubilized St can be determined.     

A full‐color eyewear display using planar waveguides with reflection volume holograms

Abstract— A full‐color eyewear display with over 85% see‐through transmittance with a 16° horizontal field of view was developed. Very low color crosstalk, less than 0.008 Δu′v′ uniformity, and 120% NTSC color gamut were achieved. Waveguides with two in‐ and out‐coupling reflection volume hologram elements enabled a simple configuration that has an optical engine beside the user's temples. The reflection volume hologram elements used on the waveguides realized a small thickness of 1.4 mm for each waveguide, and an out‐coupling reflection volume hologram used as an optical combiner contributed a high see‐through transmittance of 85% due to its wavelength selectivity. However, there are technical challenges in achieving a reasonable screen size and quality color images with optics that utilize holographic waveguides because holograms have large chromatic dispersions compared to conventional optical elements such as lenses and mirrors. Approaches to overcome these issues are described.