Speech errors, phonotactic constraints, and implicit learning: A study of the role of experience in language production.

Speech errors follow the phonotactics of the language being spoken. For example, in English, if [n] is mispronounced as [ ], the [ ] will always appear in a syllable coda. The authors created an analogue to this phenomenon by having participants recite lists of consonant–vowel–consonant syllables in 4 sessions on different days. In the first 2 experiments, some consonants were always onsets, some were always codas, and some could be both. In a third experiment, the set of possible onsets and codas depended on vowel identity. In all 3 studies, the production errors that occurred respected the phonotactics of the experiment. The results illustrate the implicit learning of the sequential constraints present in the stimuli and show that the language production system adapts to recent experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tolyl-Substituted Siloles: Synthesis, Substituent Effects, and Aggregation-Induced Emission

The syntheses, spectroscopic characteristics, and electrochemical behavior of 1,1-dimethyl-2,5-diphenyl-3,4-bis(p-methylphenyl)silole and 1,1-dimethyl-2,3,4,5-tetra(p-methylphenyl)silole are reported. The compounds are weakly luminescent in dilute fluid solution but exhibit dramatic aggregation-induced emission (AIE). Absorbance, luminescence, and voltammetric characteristics are compared to 1,1-dimethyl-2,3,4,5-tetraphenylsilole and 1,1-dimethyl-3,4-diphenyl-2,5-bis(p-methylphenyl)silole, allowing a comparison of the effects of the position of the substituents on the silole ring. In addition, HOMO and LUMO energies and band gaps, derived from electrochemical, spectroscopic, and computational data, are reported. Substitution of the weakly electron-donating p-methyl groups on the peripheral aryl groups at the 2- and 5-positions of the silole ring results in slight red shifts in absorption and emission maxima, slight enhancement of luminescence quantum yields, slightly longer luminescence lifetimes, and more anodic oxidation potentials.     

Equal-Channel Angular Extrusion of a Low-Density High-Entropy Alloy Produced by High-Energy Cryogenic Mechanical Alloying

In this study, we demonstrate the feasibility of forming a bulk consolidated, low-density high-entropy alloy, namely AlFeMgTiZn, which shows reasonable mechanical properties and high hardness. The fabrication of the high-entropy alloy from powdered precursors via high-energy mechanical alloying as a function of milling time is presented. In turn, the evolution of the alloy microstructure with postmilling anneal treatment is elucidated. Last, the severe plastic deformation processing methodology, i.e., equal-channel angular extrusion, chosen for consolidation, is described and shown to result in a bulk product with good results.     

Laser deposited biocompatible Ca–P coatings on Ti–6Al–4V: Microstructural evolution and thermal modeling

A high intensity continuous wave diode pumped ytterbium laser source was used to deposit Ca–P coatings on a Ti–6Al–4V biocompatible alloy in order to generate a physically textured surface, enhancing osseointegration. Scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM) and energy dispersive spectroscopy (EDS) studies were coupled with X-ray and micro diffraction work to determine the structure, composition, and phases present in various zones of a sample prepared across the coating/substrate interaction zone. Three-dimensional thermal modeling was also carried out to determine the cooling rate and maximum temperature experienced by different regions of the substrate. Combining these results provide us with valuable insights regarding the thermo-physical as well as chemical interactions that take place across the coating–substrate interface.     

Photochemical Formation of Brominated Dioxins and Other Products of Concern from Hydroxylated Polybrominated Diphenyl Ethers (OH-PBDEs)

The photochemical conversion of selected hydroxylated polybrominated diphenyl ethers (OH-PBDEs) to dioxins and other products was investigated. OH-PBDEs, which are both transformation products of polybrominated diphenyl ethers and naturally occurring compounds, undergo direct photolysis to yield a number of products that may have a higher toxicity than their parent. The compounds investigated were 6-OH-PBDE 99, 6'-OH-PBDE 100, and 6'-OH-PBDE 118. Of special interest was 6'-OH-PBDE 118, a potential transformation product of PBDE 153 that is capable of photochemically generating 2,3,7,8-tetrabromodibenzo-p-dioxin, the most toxic brominated dioxin congener. Photolysis experiments were conducted at two different pH values to assess the photochemical behavior of both the phenol and phenolate form of the compounds. The percent conversion to dioxin and other photoproducts was determined and the natural product, 6-OH-PBDE 99, was found to have the highest conversion to dioxin (7%). The reaction quantum yields ranged from 0.027 to 0.16 across all photolysis conditions. In addition, it is shown that all three compounds are capable of photochemically generating other compounds of concern, including brominated phenols and a dibenzofuran.     

Proinflammatory activity and the sensitization of depressive-like behavior during maternal separation.

When guinea pig pups are isolated for a few hours in a novel environment, they exhibit a distinctive passive behavioral response that appears to be mediated by proinflammatory activity. Recently, we observed that pups separated on two consecutive days show an enhanced (sensitized) passive response on the second day. In Experiment 1, pups receiving intracerebroventricular infusion of 50 ng of the anti-inflammatory cytokine interleukin-10 prior to a first separation failed to show a sensitized behavioral response to separation the next day. In Experiment 2, pups separated on Days 1 and 2, or just 2, showed an increase in passive responding during separation on Day 5. Pups injected with the bacterial antigen lipopolysacchride (LPS; 75 μg/kg body weight, intraperitoneal) prior to separation on Day 1 showed an increase in passive behavior several days later not shown by pups injected with saline prior to Day 1 separation. However, injection of LPS without separation on the first day did not enhance responding during an initial separation on the second day. These results suggest that immune activation is necessary, but not sufficient, to account for the sensitization of passive behavior of isolated guinea pig pups the following day, that boosting proinflammatory activity during an initial separation may promote sensitization several days later, and that the sensitized response persists for at least several days. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Insomnia and well-being.

Most Americans have occasional problems with insomnia. The relationship of insomnia to illness is well known. However, insomnia may also relate to lower levels of well-being. Although there are various definitions of well-being, one of the most clearly articulated and comprehensive models identifies 2 overarching constructs, psychological well-being and subjective well-being. The purpose in the present study was to assess the relationship between insomnia symptoms and the dimensions of psychological and subjective well-being, adjusting for the potential confound of comorbid physical and psychological illness. The data for the present study came from the National Survey of Midlife Development in the United States, a survey of community-dwelling adults. After adjustment for demographic characteristics and a wide range of chronic mental and physical health conditions, insomnia symptoms were found to have a significant relationship with both psychological and subjective well-being but a stronger relationship to subjective well-being. These data suggest that insomnia symptoms have a stronger relationship to enjoying life than to the perception that one has a meaningful life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Magnetic assembly of high-density DNA arrays for genomic analyses

A method for rapidly assembling high-density DNA arrays with near-perfect order is described. Photolithography is used to generate a wafer-scale array of microwells in a layer of photoresist on a chemically functionalized glass coverslip. The array is enclosed within a microfluidic device, and a suspension of superparamagnetic microbeads conjugated to DNA molecules is introduced into the chamber. A permanent magnet is used to direct the rapid assembly of the beads into the wells, with each well containing a single bead. These beads are immobilized on the glass surface via affinity binding, and excess beads can be recycled or washed away. Nonspecifically bound beads are removed by dissolving the photoresist. The result is a high-density array of beads with virtually no background. This method can be used to produce protein arrays for chip-based assays and DNA arrays for genotyping or genome sequencing.     

Mechanical properties of electrodeposited nanocrystalline copper using tensile and shear punch tests

Characterization of the mechanical properties of electrodeposited nanocrystalline Cu with an average grain size of 74 nm was carried out using two different testing techniques, shear punch tests and tensile tests. The grain size distribution was broad and the volume fraction of larger grains was appreciable. The electrodeposited Cu had a high yield strength combined with moderate ductility and strain hardening. Scatter in the ductility values was attributed to residual porosity and inhomogeneity in the microstructure. Measurements of the strain rate sensitivity showed a significant increase in the rate sensitivity and a decrease in the activation volume for the deformation of nanocrystalline Cu compared with similar tests on coarse-grained cold worked Cu.