On sex differences in spatial abilities.

The present author agrees with the suggestions by P. J. Caplan et al (see record 1986-10956-001) that sex differences in average performance on spatial tasks are often modest in magnitude and inconsistent from one task to another and that spatial ability is not a unitary construct; however, their contentions that sex differences in spatial abilities are nonexistent and that the concept of spatial abilities is not sufficiently valid as to allow meaningful investigation of sex differences are challenged. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Safety Analysis Results for ITER In-Vessel Loss of Coolant Events

A number of postulated in-vessel loss of coolant accidents (LOCAs) associated with the first wall and baffle cooling systems of the ITER detailed design have been analyzed for the ITER Non-site Specific Safety Report (NSSR-1). A range of break sizes from one first wall tube break (1.57 × 10^–4 m²) to damage to all in-vessel components (0.6 m² break) have been examined. These events span the ITER event classification from likely events to extremely unlikely events. In addition, in-vessel pipe breaks in combination with bypass of the two confinement barriers through a generic penetration have been examined. In all cases, when the vacuum vessel pressure suppression system is activated, most of the radioactive inventory is carried to the suppression pool where it remains for the duration of the event. Releases in these events are well within ITER release limits.     

A longitudinal study of the performance of hypertensive and normotensive subjects on the Wechsler Adult Intelligence Scale.

Performance on the Wechsler Adult Intelligence Scale (WAIS) was followed over 2 5- to 6-year intervals for essential hypertensive Ss (EH; n?=?22) free from medical complications and for normotensive Ss (N; n?=?20). EH were treated with adrenergic beta-blocking drugs, diuretics, or both. Mean age was 46 years (SD?=?12.6 years), initially (Time 1). Results were unaltered by adjustment for initial age. N improved modestly on the Verbal scale, from Time 1 to Time 2 only. EH neither improved nor declined on the Verbal scale. Scores remained unchanged for both EH and N Ss for the Performance scale. Overall, and at Times 2 and 3, Verbal scores were lower for the EH group. It was concluded that neither decline nor improvement in cognitive function over time are necessary outcomes of modest, carefully treated, uncomplicated hypertension in the middle years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antenatal hormone therapy for fetal lung maturation

In summary, several agents have been studied, but only CS and thyroid hormones have been found to accelerate fetal lung maturation in animal studies. Thirty years of research has documented the beneficial effect of antenatal CS on fetal lung maturation, and antenatal steroid in combination with postnatal surfactant remains the mainstay of prevention and therapy for RDS in preterm infants. The efficacy and safety of postnatal steroids have yet to be demonstrated. Unfortunately, the addition of antenatal TRH to this regimen has not provided further benefit to the neonatal outcome of preterm infants as evidenced by the recently completed multicenter trials. In addition, the optimal number of courses of antenatal CS for lung maturation remains unclear.     

Age-related differences in concurrent-task performance of normal adults: Evidence for a decline in processing resources.

A concurrent-task paradigm was used to investigate age-related differences in the attentional capacity of 92 right-handed adults. Young, middle-aged, and elderly Ss were compared as they performed speeded, unimanual finger tapping with and without concurrent silent reading, speaking, and maze completion. There were 2 levels of difficulty for each cognitive task. The decrement in tapping rate from the single- to dual-task condition increased linearly with age. Concurrent-task tapping was slowed more by difficult than by easy tasks, and difficult tasks had a disproportionately disruptive effect on the concurrent performance of elderly Ss. The heightened vulnerability of the elderly to concurrent-task effects cannot be attributed parsimoniously to either general slowing or diminution of a specific resource. Instead, the results suggest a reduction in a general-purpose processing resource with increasing age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Poly(ethylene oxide) Grafted to Silicon Surfaces: Grafting Density and Protein Adsorption

Poly(ethylene oxide) (PEO) polymer, in linear and star form, was covalently grafted to silicon surfaces, and the surfaces were tested for their ability to adsorb proteins. Linear PEG of molecular weight 3400, 10 000, and 20 000 g/mol and star PEO molecules were coupled via their terminal hydroxyl groups activated by tresyl chloride to aminosilane-treated silicon wafers. The amount of PEO coupled to the surface was varied by changing the concentration of the tresyl-PEO solution. The dry PEO thickness on the surface was measured using X-ray photoelectron spectroscopy (XPS) and ellipsometry, from which the grafting density was calculated. The PEO surfaces were exposed to solutions of each of three proteins: cytochrome-c, albumin, and fibronectin. The degree of adsorption of each protein was determined by XPS and ellipsometry and recorded as a function of PEO grafting density. All three proteins were found to reach zero adsorption at the highest grafting densities on all three PEG surfaces, which for all three PEG surfaces was a PEO content of 100 +/- 10 ng/cm2. On both star PEO surfaces, albumin and fibronectin decreased to zero adsorption at intermediate values of grafting density, whereas cytochrome-c continued to adsorb at all grafting densities, although with a decreasing trend. A physical model of the surface helped explain these protein adsorption results in terms of the spacing and degree of overlap of grafted PEO chains.     

Photophysical processes and interactions between poly(ethylene terephthalate) and 1-amino-2-(2-methoxyethoxy)-4-hydroxy-9,10-anthraquinone

The effect of 1-amino-2-(2-methoxyethoxy)-4-hydroxy-9,10-anthraquinone (C. I. Disperse Red 59) on the phototendering of poly(ethylene terephthalate) (PET) was assessed. The photophysical processes occurring in the polymer, the dye, and the dyed polymer were determined. The energy and nature of the dye and polymer electronic excited states were assigned on the basis of absorption and luminescence properties. Irradiation failed to produce dye-sensitized phototendering of PET; however, the titanium dioxide delusterant in commercial PET did function as a sensitizer in the presence of moist air. The phototendering of blank-dyed PET yarn was found to obey (pseudo-) zero-order kinetics k = 1.69 × 10^?19 per cent breaking strength loss/quantum absorbed/cm². The dye exhibited fluorescence from a lowest, ～51.5 kcal/mole, singlet charge-transfer (C-T) excited state but did not phosphoresce. The PET possessed a complex fluorescence spectrum attributed to similar ¹(n,π^*)₁ excited states, ～78.1 kcal/mole, while its phosphorescence derives from a proposed ³(π,π^*) state, ～69.8 kcal/mole, populated by intersystem crossing from a ¹(π,π^*) state, ～92.3 kcal/mole. The dyed polymer exhibited a PET-sensitized delayed fluorescence from the dyestuff involving triplet–singlet transfer by a dipole–dipole (Coulumbic) long-range resonance excitation mechanism. The transfer process was characterized by an experimentally determined critical transfer distance, R₀, of approximately 40 Å.     

Phase Transformation Kinetics in the System Bismuth Oxide-Zirconia

The effect of ZrO₂ addition on the phase transformation of Bi₂O₃ was studied with powder X-ray diffraction and differential thermal analysis. Samples containing higher than a few mole percent ZrO₂ were obtained as the metastable β phase (tetragonal) at room temperature when they were cooled at 20°C/min from 800°C where the δ phase (fcc) is stable. When the same samples were cooled at the same rate from 1000°C, which is above the solidus, they formed the stable α phase (monoclinic) at room temperature. Evidence for the relatively higher solubility of ZrO₂ in the α phase is discussed to explain this observation.