Prenatal and neonatal testosterone exposure interact to affect differentiation of sexual behavior and partner preference in female ferrets.

Implanting testosterone (T) subcutaneously over Postnatal Days 5–20 masculinized sexual behavior, reduced proceptive responsiveness, and shifted sexual preference more readily in male than in female ferrets gonadectomized on Day 5. This enhanced sensitivity of males to neonatal T was best duplicated in females exposed transplacentally to T over Embryonic Days (E) 27–39 (41-day gestation) and injected at birth with T (2.5 μg sc in oil:10% ethanol). Extended exposure of male ferrets to high levels of T, beginning shortly after the onset of testicular steroidogenesis (E25) and continuing for several hours after birth (E41) normally sensitizes their brains to the subsequent organizational effects on coital performance and sexual motivation of the relatively low levels of T that circulate in male ferrets during the first 3 postnatal weeks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Coating and near‐surface modification design strategies for protective and functional surfaces

This paper discusses strategies for controlling the surface chemistry and microstructure of materials to form protective and functional surfaces through controlled gas‐metal reactions. Potential applications range from oxidation, corrosion, and wear resistance to electrochemical devices such as fuel cells to catalysts. Phenomenological examples are presented for coatings designed to self‐grade under oxidizing conditions, and for the growth of simple and complex (binary and ternary) nitride and carbide phase surface layers by nitridation and carburization reactions. Specific systems discussed include environmental barrier coatings (EBCs) for Si‐based ceramics such as Si₃N₄ and SiC, the growth of continuous, protective CrN/Cr₂N, TiN, VN, NiNbVN, and related simple nitride layers on Fe‐ and Ni‐base alloys, the possible formation of ternary nitride and carbide surface phases (e.g. Ti₃AlC₂ and related MAX‐phases) on intermetallic surfaces to improve oxidation resistance, and the formation of composite near‐surface structures in Ag‐SiO₂ and Co(Mo)‐Co₆Mo₆C₂ systems.     

Photoluminescence plasmonic enhancement in InAs quantum dots coupled to gold nanoparticles

Photoluminescence enhancement due to dipole field from gold nanoparticles was observed at 77 K for GaAs capped InAs quantum dots. The gold nanoparticles were coupled to the surface of the cap layer by using dithiol ligands. The enhancement was investigated as a function of the GaAs capped layer thickness. An order of magnitude enhancement in the emission was observed in samples with a cap thickness of 12 nm. This enhancement however is drastically decreased in samples with a cap thickness of 200 nm. The observed enhancement is interpreted in terms of photon scattering from the large dipole scattering cross section.     

Polarization dynamics and non-equilibrium switching processes in ferroelectrics

Time- and temperature-dependent effects are critical for the operation of non-volatile memories based on ferroelectrics. In this paper, we assume a domain nucleation process of the polarization reversal and we discuss the polarization dynamics in the framework of a non-equilibrium statistical model. This approach yields analytical expressions which can be used to explain a wide range of time- and temperature-dependent effects in ferroelectrics. Domain wall velocity derived in this work is consistent with a domain wall creep behavior in ferroelectrics. In the limiting case of para-electric equilibrium, the model yields the well-known Curie law. We also present experimental P-E loops data obtained for soft ferroelectrics at various temperatures. The experimental coercive fields at various temperatures are well predicted by the coercive field formula derived in our theory.     

Roadwise Review has limited congruence with actual driving performance of aging drivers

The Roadwise Review (RR) CD-ROM has been proposed as one way for older drivers to self-evaluate the skills that support safe driving. To better gauge the utility of RR for that purpose, further validation of RR vis-à-vis measures of driving performance is needed. We carried out this study to provide such validation. We correlated the results of the standard Useful Field of View subtest 2 (UFOV-2) and Trail Making Test (TMT) parts A and B to the corresponding RR subsections on visual information processing and visual search. We further examined the correlations between on-road performance (based on demerit points) and RR results (absolute scores and number of problems identified). The correlations between UFOV-2, TMT and the relevant RR sections ranged from .46 to .61. The correlations between demerit points and RR absolute values ranged from −.40 to .50. The correlations between demerit points and the number of problems identified by RR ranged from −.24 to .45. Using a “pass/fail” approach we also failed to find a relationship with the number of problems. These results indicate limited convergence between findings obtained with RR and actual performance using standardized approaches. Such results emphasize the importance of developing a rigorous data synthesis process before attempting knowledge translation of material aimed at older drivers.     

FR139317, a specific ETA-receptor antagonist, inhibits cerebral activation by intraventricular endothelin-1 in conscious rats

A comprehensive series of time-related behavioral, physiological and cerebral metabolic studies was conducted using conscious Sprague-Dawley rats to discern the anti-endothelin (ET) properties of the specific ETA receptor antagonist, FR139317. Endothelin-1 (9 pmol given by injection into one lateral ventricle, i.c.v.) produced convulsions, acute arterial hypertension, arterial hyperglycemia, and hyperventilation. Brain structures close to the i.c.v. site of injection, such as the caudate nucleus, lateral septal nucleus, corpus callosum and hippocampal CA3 medial lamellae, as well as 14 other individual structures, displayed moderate-to-intense levels of metabolic activation after endothelin. Data were assessed quantitatively by means of the autoradiographic [14C]deoxyglucose technique combined with image analysis. Neural circuits in the efferent projection paths of the stimulated forebrain structures, such as the midbrain oculomotor complex, amygdaloid nuclei, substantia nigra pars reticulata and caudal subicular subregions of the hippocampal formation, were stimulated focally by endothelin. Specific medullary nuclei and cerebellar cortical subregions displayed high rates of glucose metabolism following endothelin injection at the time of maximum behavioral and physiological stimulation. I.c.v. treatment with > or = 14 nmol FR139317 before endothelin significantly inhibited the effects produced by the peptide. At the highest dose of FR139317 (28 nmol), there was only mild behavioral stimulation following endothelin injection, and hypermetabolic responses in the brain were abolished except in two specific areas of the cerebellar cortex (approx 40% increases in metabolic activity in the copula pyramis and paramedian lobule). The results indicate that the cerebral stimulatory effects of i.c.v. endothelin are mediated by the A type of endothelin receptor. By itself, i.c.v. FR139317 had no effects on the parameters assessed. Further evaluation of FR139317 is warranted as a possible therapeutic agent for neuropathologies suspected of deriving from central neural or vascular stimulation by endothelin, such as aneurysmal vasospasm, ischemia, excitotoxicity, and peptide-mediated epilepsies.     

A Content Analysis of Print News Coverage of Media Violence and Aggression Research

We conducted a content analysis of news articles (N = 540) to examine whether news coverage of media violence accurately reflects scientific knowledge about exposure to media violence and its effects on viewer aggression. The analysis revealed that over the past 30 years, news articles generally suggested that a link between media violence and aggression exists. However, the tone shifted sharply back toward a neutral conclusion since 2000. This shift may be attributable to the type of medium discussed (e.g., television vs. video games), the number of unaffiliated sources that are cited in the news article, and the sex of the journalist. Implications for how this news coverage may influence news readers are discussed.