Visual word recognition without central attention: Evidence for greater automaticity with advancing age.

The present experiments examined the automaticity of word recognition. The authors examined whether people can recognize words while central attention is devoted to another task and how this ability changes across the life span. In Experiment 1, a lexical decision Task 2 was combined with either an auditory or a visual Task 1. Regardless of the Task 1 modality, Task 2 word recognition proceeded in parallel with Task 1 central operations for older adults but not for younger adults. This is a rare example of improved cognitive processing with advancing age. When Task 2 was nonlexical (Experiment 2), however, there was no evidence for greater parallel processing for older adults. Thus, the processing advantage appears to be restricted to lexical processes. The authors conclude that greater cumulative experience with lexical processing leads to greater automaticity, allowing older adults to more efficiently perform this stage in parallel with another task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intersubband gain and stimulated emission in long-wavelength(λ=13 μm) intersubband In(Ga)As-GaAs quantum-dotelectroluminescent devices

The dynamics of injected carriers and the conditions for intersubband gain and population inversion in In(Ga)As-GaAs self-organized quantum dots have been studied. Direct femtosecond pump-probe spectroscopy as a function of temperature and excitation density confirms earlier results and shows a long (>100 ps) electron relaxation time between the excited states and ground state in the dots. Intersubband gains as high as 170 cm^-1 are calculated in the dots. Far-infrared spontaneous emission centered around 13 μm is observed in edge-emitting light-emitting diodes. Stimulated emission, with a distinct threshold around 1.1 kA/cm² in the light-current characteristics, is observed in plasmon-enhanced waveguide devices. The intersubband threshold occurs after a threshold is observed for interband lasing (~1 μm) in the same device     

An analysis of ethnic differences in UK graduate migration behaviour

In this paper, we analyse the employment–migration behaviour of 13,753 UK university graduates. In particular, we distinguish between five different types of sequential migration behaviour from domicile to higher education and on to employment. By controlling for a range of variables relating to human capital acquisition, local economic conditions and personal characteristics, we are able to identify the role of ethnicity in determining the interregional migration behaviour of university graduates.

Comparison of the effects of methamphetamine, bupropion, and methylphenidate on the self-administration of methamphetamine by rhesus monkeys.

The effectiveness of methadone as a treatment for opioid abuse and nicotine preparations as treatments for tobacco smoking has led to an interest in developing a similar strategy for treating psychostimulant abuse. The current study investigated the effects of three such potential therapies on intravenous methamphetamine self-administration (1 – 30 μg/kg/injection) in rhesus monkeys. When given as a presession intramuscular injection, a high dose of methamphetamine (1.0 mg/kg) decreased intravenous methamphetamine self-administration but did not affect responding for a food reinforcer during the same sessions. However, the dose of intramuscular methamphetamine required to reduce intravenous methamphetamine self-administration exceeded the cumulative amount taken during a typical self-administration session, and pretreatment with a low dose of methamphetamine (0.3 mg/kg) actually increased self-administration in some monkeys at the lower self-administration dose. Like pretreatment with methamphetamine, pretreatment with bupropion (3.2 mg/kg) decreased methamphetamine self-administration but did not affect responding for food. Pretreatment with methylphenidate (0.56 mg/kg) did not significantly alter methamphetamine self-administration. These results suggest that some agonist-like agents can decrease methamphetamine self-administration. Although the most robust effects occurred with a high dose of methamphetamine, safety and abuse liability considerations suggest that bupropion should also be considered for further evaluation as a methamphetamine addiction treatment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Radar measurement of bridge scour

Scour around bridge piers and abutments has resulted in many structural failures over the past decade and considerable research has been carried out to develop methods which can be used to evaluate the risk of scour affecting the integrity of these major structures. Traditional site investigation methods based on borehole core and samples of the riverbed sediments are expensive and time-consuming and may not always give a complete assessment of the lithological variation in the riverbed sediments. Geophysical methods can be used to determine the riverbed profile beneath the water in a river and may also be of value for obtaining the previous scour history below the riverbed level.Trials of ground penetrating radar (GPR) have indicated that this geophysical method is particularly effective in determining the sub-bottom geological structure in a shallow freshwater environment. In this presentation the results from a number of scour surveys using GPR are presented and discussed. It is concluded that GPR surveys can be effective in determining both the water depth and sub-bottom geological structure near bridge piers and abutments provided that the correct instrumentation and operational procedures are adopted.     

Does concept-oriented reading instruction increase strategy use and conceptual learning from text?

The authors define reading engagement as the mutual support of motivations, strategies, and conceptual knowledge during reading. To increase reading engagement, a collaborative team designed a year-long integration of reading/language arts and science instruction (Concept-Oriented Reading Instruction, CORI). The authors compared students who received this instruction to similar students who received traditionally organized instruction aimed toward the same objectives. A path analysis showed that CORI had a positive effect on strategy use and text comprehension for students at Grades 3 and 5 when accounting for past achievement and prior knowledge. CORI also had a positive, indirect effect on conceptual knowledge mediated by strategy use, and this instruction facilitated conceptual transfer indirectly through several paths simultaneously. The findings are discussed in relation to a growing literature on instructional contexts for motivated strategy use and conceptual learning from text. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selective serotonin reuptake inhibitors dissociate fenfluramine's anorectic and neurotoxic effects: importance of dose, species and drug

Fenfluramine, a clinically prescribed appetite suppressant, has been found to damage brain serotonin (5-HT) neurons in every animal species tested to date. Recent findings indicate that fluoxetine, a selective 5-HT reuptake inhibitor (SSRI), can prevent fenfluramine-induced 5-HT neurotoxicity without blocking fenfluramine-induced appetite suppression. The purpose of our studies was several-fold: 1) To determine whether the ability for fluoxetine to dissociate fenfluramine-induced anorexia and neurotoxicity is dose-related; 2) to ascertain whether other SSRIs also prevent fenfluramine-induced neurotoxicity without altering its anorectic effect; 3) to determine whether similar fluoxetine/fenfluramine interactions are seen in another animal species (i.e., mice) and 4) to determine whether decreases in food intake seen after the fluoxetine/fenfluramine combination can be attributed to nonspecific behavioral suppression. Results from our studies indicate that fluoxetine's effects are, indeed, dose-related, because higher doses of fluoxetine are required to protect against the 5-HT neurotoxic effects of higher doses of fenfluramine. Further, our results indicate that fluoxetine's effects generalize to all other SSRIs tested (citalopram, paroxetine and sertraline), as well as to other species (mice). Finally, our results demonstrate that anorexia in animals receiving the fenfluramine/fluoxetine combination is not secondary to nonspecific behavioral suppression, because water intake is increased although food intake is decreased in the same animals. Together, these data suggest that the anorectic and 5-HT neurotoxic effects of fenfluramine may involve different mechanisms, and that by combining fenfluramine with SSRIs, it may be possible to exploit fenfluramine's clinically useful properties (e.g., anorexia) without risking brain 5-HT neural injury.     

The transition to parenthood among young African American and Latino couples: Relational predictors of risk for parental dysfunction.

This study examined relationship factors associated with parental dysfunction among young African American and Latino couples. Parent dysfunction was defined in terms of parenting stress, child abuse potential, physically punitive behavior, and paternal disengagement. Fathers who reported positive relations with their own parents and partners before childbirth reported more positive adjustments to parenthood at follow-up. The quality of the prebirth partner relationship buffered the impact of a relationship breakup on a young father's adjustment to parenthood. The quality of a mother's relationship with her parents was the best predictor of her adjustment to parenthood. However, mothers who reported large declines in the quality of the partner relationship also reported high levels of parenting stress. Clinical and policy implications of findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Locus coeruleus lesions decrease norepinephrine input into the medial preoptic area and medial basal hypothalamus and block the LH, FSH and prolactin preovulatory surge

Phagocytosis is a fundamental process in innate resistance to infection. We have used the pathogenic yeast Cryptococcus neoformans to study the interaction of this encapsulated organism with murine macrophages in vitro. In the absence of exogenous opsonins the encapsulated yeast is almost totally resistant to ingestion by murine macrophages. Owing to its ability to activate the alternative complement pathway, the anti-phagocytic properties of the polysaccharide capsule can be partially overcome following opsonization in vitro with non-immune mouse serum and subsequent phagocytosis via complement receptors. Here, we demonstrate the importance of the complement receptor type 3 (CR3) in in vitro phagocytosis of the yeast and in in vivo resistance to infection. In vitro, 70% of a population of resident murine macrophages are able to ingest C. neoformans and then only inefficiently (1-2 organisms per cell). Previously we have shown that tumour necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) efficiently enhance ingestion of serum-opsonized encapsulated C. neoformans, and we now show that the cytokines convert a population of resident macrophages to a state where all the cells are competent for ingestion of large numbers of yeasts (6-8 per cell). We also show that these cytokines have a direct effect on CR3, as enhanced levels of complement-opsonized sheep red blood cells (EIgMC) bind to macrophages activated in this way. However, cytokines that have previously been shown to enhance phagocytosis of EIgMC have no effect on ingestion of encapsulated C. neoformans. These results demonstrate that the cytokines regulating CR3-dependent ingestion of C. neoformans are different to those regulating ingestion of EIgMC and reinforce the importance of studying pathogens rather than inert ligands in understanding the regulation of phagocytosis.     

Criteria for practical fusion power systems: Report from the EPRI fusion panel

Electric utilities are keenly interested in the promise of fusion: large-scale electricity production anywhere, with virtually no natural resource depletion or environmental pollution. To expedite development of commercially viable fusion systems, the Electric Power Research Institute (EPRI)—the R&D wing of the U.S. electric utility industry—recently convened a panel of top utility R&D managers and executive officers to identify the key criteria that must be met by fusion plants in order to be acceptable to utilities. The panel's findings, summarized in this report, emphasize competitive economics, positive public perception, and regulatory simplicity.now Senior Vice President, General Atomics.