Regulatory aspects of emissions trading: Conflicts between economic and environmental goals

Emissions trading can provide a least-cost path for acid rain control for electric utilities. But there are many ways regulators — intentionally or inadvertently — can bias utilities' response to the new order.     

Dissociations among the anxiolytic effects of septal, hippocampal, and amygdaloid lesions.

Fear reactions of rats given bilateral lesions to the septum, hippocampus, or amygdala were compared with those of rats given sham lesions, in 2 animal models of anxiety: the shock-probe burying test and the elevated plus-maze test. Septal lesions produced anxiolytic effects in both tests (i.e., an increase in open-arm activity and a decrease in burying), whereas hippocampal and amygdaloid lesions produced neither of these effects. On the other hand, hippocampal and amygdaloid lesions impaired rats' passive avoidance of the electrified shock-probe, whereas septal lesions did not. These dissociations suggest that limbic structures such as the septum, amygdala, and hippocampus exert parallel but distinct control over different fear reactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interphase effects in polymer-modified hydraulic cements

Earlier work has indicated the importance of interphase adhesion within these systems. The work here reported shows that, with reactive polymers, substantial chemical modification occurs at the surface of the polymer latex particle. With certain polymer types, such as polyethylene and polystyrene homopolymers, no evidence is found of such reactions; with others, such as poly(vinylidene chloride, vinyl chloride) and poly(ethyl acrylate, methyl methacrylate), substantial reaction occurs. Crosslinking and insolubilization frequently accompany these reactions, and the nature of the polymer is significantly altered.     

In vitro release of betamethasone -17- valereate from various dermatological bases

Betamethasone -17- Valereate release characteristics, from several commercial dermatological bases, were evaluated before and after dilution with several excipients.

It was found that betamethasone releases faster from creams than from ointments. In addition the release of the corticosteroid is affected by the composition of the diluting excipient.     

The Geoscience Laser Altimeter System (GLAS) Laser Transmitter

The Geoscience Laser Altimeter System (GLAS), launched in January 2003, is a laser altimeter and lidar for the Earth Observing System's (EOS) ICESat mission. GLAS accommodates three, sequentially operated, diode-pumped, solid-state, Nd:YAG laser transmitters. The laser transmitter requirements, design, and qualification test results for this space-based remote-sensing instrument is summarized and presented.     

Burying as a defensive response in rats.

Notes that in typical laboratory settings, the defensive reactions of animals appear to be limited to freezing, fleeing, and attacking. However, 95 naive adult male hooded rats tested in the presence of bedding material incorporated it into a striking and adaptive behavioral sequence. Ss shocked once through a stationary prod buried this shock source, even when the shock–test interval was 20 days. Moreover, the burying seemed to be guided specifically by the relation between the prod and the shock; Ss shocked through a grid did not bury the prod, and Ss shocked by 1 of 2 identical prods buried only the shock prod. Thus, the usual assumption that the rat's defensive repertoire is limited to a few simple behaviors appears to have been shaped by the constraints of standard testing environments rather than by the actual propensities of the rat. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

DS/CDMAM-ary orthogonal signalling in a shadowed Rayleigh channel for mobile communications

In this paper a modified RAKE receiver is studied for a frequency selective mobile radio channel. The reverse link (Mobile to base station) is analysed, assuming lognormal shadowing and Rayleigh fading andK asynchronous users, withM orthogonal sequences per user. The analysis is based on the consideration of the quadrature components of the signal and noise, taking advantage of the multipath effects. The performance evaluation is carried out in terms of both the bit error rate and outage probability in order to qualify completely the proposed receiver. The positive results assure the possibility of applying this system in a microcellular mobile radio environment.     

Gas-cluster ion-beam smoothing of chemo-mechanical-polish processed GaSb(100) substrates

Gas-cluster ion-beam (GCIB) processing of surfaces provides individual atoms within an accelerated gas cluster (∼1,500 atoms per cluster), an energy approximately equal to the individual bond energy of the target surface atoms. The gas-cluster beam is thus capable of providing smoothing and etching of the extreme surface of numerous semiconductors, metals, insulators, and magnetic materials. For semiconductor material systems, the gas-cluster processing effect on the surface and subsurface material is of critical interest for device and circuitry application integrity. In the case of III–V GaSb, chemo-mechanical or touch polishing is the final step in the semiconductor-wafer manufacturing process, often leaving scratches of various depths or damage on the polished surface. In this paper, we report the GCIB etching and smoothing of chemical-mechanical polished GaSb(100) wafers. Using a dual-energy, dual gas-cluster source process, ∼100 nm of material was removed from a GaSb(100) surface. Atomic-force microscopy (AFM) imaging and power spectral-density (PSD) analysis shows significant decrease in the post-GCIB root-mean-square (Rms) roughness and peak-to-valley measurements for the material systems. X-ray rocking-curve analysis has shown a 24-arcsec reduction in the full-width at half-maximum (FWHM) of the (111) x-ray diffraction peak of GaSb. High-resolution transmission-electron microscopy (HRTEM) shows the crystallinity of the subsurface of the pre- and post-GCIB surfaces to be consistent, following the 1 × 10¹⁶ ions/cm² total-fluence processes, with dislocation density for both pre- and post-GCIB cases below the HRTEM resolution limit. X-ray photoelectron spectroscopy (XPS) indicates a strong Ga 3p electron binding-energy intensity for gallium-oxide formation on the GaSb surface with the use of an oxygen GCIB process. Analysis of the Ga 3p electron binding-energy peaks in the XPS data in conjunction with HRTEM indicates a higher Ga or GaSb content in the near-surface layer (less stoichiometric-oxide presence) with use of a CF₄/O₂ GCIB process. The same peak analysis indicates that the surface gallium-oxide state is nearly unchanged, except in thickness, with the use of an O₂-GCIB second step. The material results suggest that GCIB provides a viable method of chemo-mechanical polish (CMP) damage removal on group III–V material for further device processing.     

Maximum likelihood estimation of exponential distribution parameters using interval data

This paper addresses the problem of estimating, by the method of maximum likelihood (ML), the location parameter (when present) and scale parameter of the exponential distribution (ED) from interval data. Interval data are defined as two data values that surround an unknown failure observation. Such observations occur naturally, during periodic inspections, for example, when only the time interval during which the failure occurred is known. The appropriate (conditional) log-likelihood functions are derived, as are expressions for the asymptotic variances and covariances of the ML parameter estimates. To illustrate the calculations involved, two numerical examples are discussed.