Air-plasma Pre-treatment for Polypropylene Automotive Bumpers

The effect of forced air-plasma pre-treatment, Lectro-treat^TM, on polypropylene has been investigated using X-ray photoelectron spectroscopy (XPS), angle-resolved XPS (AR-XPS), and atomic force microscopy (AFM). The pre-treatment process is found to induce both surface chemistry changes and topographical changes. The parameters of the pre-treatment process can be optimised from these observations. The Lectro-treat pre-treatment process has been used for adhesive bonding of a demonstrator component: a bumper assembly. The adhesively bonded bumpers performed successfully in standard automotive tests.     

Cryo-EM imaging of the catalytic subunit of the DNA-dependent protein kinase

The DNA-dependent protein kinase (DNA-PK) plays an important role in mammalian DNA double-strand break repair and immunoglobulin gene rearrangement. The DNA-PK holoenzyme is activated by assembly at DNA ends and is comprised of DNA-PKcs, a 460 kDa protein kinase catalytic subunit, and Ku, a 70 kDa/80 kDa heterodimeric DNA-targeting component. We have solved the three-dimensional structure of DNA-PKcs to approximately 21 A resolution by analytically combining images of nearly 9500 individual particles extracted from cryo-electron micrographs. The DNA-PKcs protein has an open, pseudo 2-fold symmetric structure with a gap separating a crown-shaped top from a rounded base. Columns of density are observed to protrude into the gap from both the crown and the base. Measurements of the enclosed volume indicate that the interior of the protein is largely hollow. The structure of DNA-PKcs suggests that its association with DNA may involve the internalization of double-stranded ends.     

Dynamic Reconfiguration Technologies Based on FPGA in Software Defined Radio System

Partial Reconfiguration (PR) is a method for Field Programmable Gate Array (FPGA) designs which allows multiple applications to time-share a portion of an FPGA while the rest of the device continues to operate unaffected. Using this strategy, the physical layer processing architecture in Software Defined Radio (SDR) systems can benefit from reduced complexity and increased design flexibility, as different waveform applications can be grouped into one part of a single FPGA. Waveform switching often means not only changing functionality, but also changing the FPGA clock frequency. However, that is beyond the current functionality of PR processes as the clock components (such as Digital Clock Managers (DCMs)) are excluded from the process of partial reconfiguration. In this paper, we present a novel architecture that combines another reconfigurable technology, Dynamic Reconfigurable Port (DRP), with PR based on a single FPGA in order to dynamically change both functionality and also the clock frequency. The architecture is demonstrated to reduce hardware utilization significantly compared with standard, static FPGA design.     

The role of photomask resolution on the performance ofarrayed-waveguide grating devices

The crosstalk performance of an arrayed-waveguide grating (AWG) multiplexer or demultiplexer is primarily caused by random optical phase errors introduced in the arrayed waveguides. Because the layout of waveguides on a wafer is patterned via photomask through the photolithography process, the resolution of a photomask has a direct influence on the phase errors of an AWG. The paper presents a theoretical analysis on the phase error caused by photomask resolution and other basic design parameters. Both calculation and measurement results show that a high-resolution photomask (better than 25 nm) is a critical requirement to produce low-crosstalk (less than -30 dB) AWG demultiplexers. We also investigate the effect of nonideal power distribution in the arrayed waveguides because it contributes considerable phase errors when material impurity is not well controlled during wafer fabrication. Basic criteria of power profile truncation, number of grating waveguides, and material index variation are also summarized     

Comparing US and international power and control cable standards

Cables made to IEC and US standards, while having the same purpose, are of widely different designs. Cables made to one standard cannot be made to match the requirements of the other. The cable made to the US standards have been used in the US and throughout most of the world. The IEC standards have not been widely used in Europe where national and private industrial and utility standards have prevailed. IEC standards have been mainly used in countries where there have not been strong electrical codes. The European Union's adaptation of the IEC standards under the harmonized EN standards of CENELEC adds the force of law to the standards. This will promote a wider use of the IEC (CENELEC) standards on the European continent, although each country could still apply its national rules to the CENELEC standard. This is scheduled to change because all CENELEC European harmonized documents have already been withdrawn and replaced by European Norms. These are the same, word for word, in all European countries. CENELEC members are also members of the IEC and, therefore, do not operate a competitive policy with respect to the IEC. International harmonization of standards must be done at the IEC level. The addition of the CE mark to products meeting CENELEC is similar to the application of the UL mark to products meeting UL standards in the US Worldwide harmonization of standards looks to be a long process. North American and European electrical systems are based on different voltages or frequencies, different conductor sizes, and a different concept of what an electrical system should do     

Screening and treatment of distress.

The screening and treatment of psychological distress is an increasingly important aspect of providing comprehensive care to medical patients. The importance of this within oncology was illustrated most recently by the publication of the National Comprehensive Cancer Network's Distress Guidelines (Holland, 1997). Given that measures of general distress assess for symptoms across diagnostic categories, it is not unusual to have a combination of symptoms indicating distress without meeting diagnostic criteria (Derogatis, Morrow, & Petting, 1983). We would suggest that general measures of distress and psychiatric diagnoses not assessed by Coyne et al. (e.g., somatoform or adjustment disorders) may reflect better the distress (health anxiety and somatic preoccupation) of women at increased risk for cancer and be more informative than assessing selectively for mood disorders, anxiety disorders, and alcohol abuse. The authors additionally concluded that if there is not psychiatric disorder, then there is no impairment. We believe it premature at best to reify the DSM in a nonpsychiatric population. Distress exists on a continuum. To wait until patients meet psychiatric criteria before they are seen is not in the spirit of comprehensive medical care. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Damage and rock-volatile mixture effects on impact crater formation

We explored simple geologic strength and material response models to determine which have the capability to simulate impact-induced faulting, complicated ejecta patterns and complex crater shapes. This led us to develop models for material damage, dilatancy, and inhomogeneous materials (mixtures). We found that a strength degradation (damage) model was necessary to produce faulting in homogeneous materials. Both normal and thrust ring faults may occur and extend relatively deeply into the planet during the transient cavity radial expansion. The maximum depth of fault development is about the depth of maximum penetration by the projectile. Dilatancy in geologic materials may reduce the final bulk density compared to the pristine state because of irreversible fracturing. When we include the effects of dilatancy, the radial position of faulting is displaced because of greater upward motions. In addition, the late time crater profile is shallower and the expression of features such as central peaks and rings may be more pronounced. Both damage and rock-ice mixtures effect the distribution of ejecta. The excavation flow field within the heavily damaged region is similar to flow fields in Mohr-Coulomb materials with no zero-pressure strength. In the outer, less damaged zone within the excavation cavity, the material trajectories collapse back into the crater. This effect creates a zone of reduced ejecta emplacement near the edge of the final crater. In the case of rock-ice mixtures, energy is preferentially deposited in the more compressible volatile component and the ejecta pattern is dependent upon the location of shock-induced phase changes in the volatile material.     

Seismic Performance of Hillside Fills

Permanent ground deformations in unsaturated, compacted hillside fills under seismic loading conditions are discussed, with emphasis given to fill performance during the 1994 Northridge earthquake. These movements represent a significant yet often unrecognized hazard to developed hillside areas, as relatively modest deformations induced widespread damage totaling hundreds of millions of dollars during the Northridge event. The development of grading standards in the Los Angeles area is reviewed to place the seismic fill deformation problem in context with other issues that have shaped design and construction practices for hillside fills. Field observational data on fill performance during the Northridge earthquake is presented, and typical ground distress patterns are found to include cracking near cut/fill contacts, lateral extension and settlement of fill pads, and bulging of fill slope faces. For most sites, the prevalent mechanism of permanent ground deformation responsible for the fill movements is contractive volumetric strain accumulation within the unsaturated fill soils during strong earthquake shaking (that is, seismic compression).     

Validation of a system of classifying female substance abusers on the basis of personality and motivational risk factors for substance abuse.

This study explored the validity of classifying a community-recruited sample of substance-abusing women (N?=?293) according to 4 personality risk factors for substance abuse (anxiety sensitivity, introversion-hopelessness, sensation seeking, and impulsivity). Cluster analyses reliably identified 5 subtypes of women who demonstrated differential lifetime risk for various addictive and nonaddictive disorders. An anxiety-sensitive subtype demonstrated greater lifetime risk for anxiolytic dependence, somatization disorder, and simple phobia, whereas an introverted-hopeless subtype evidenced a greater lifetime risk for opioid dependence, social phobia, and panic and depressive disorders. Sensation seeking was associated with exclusive alcohol dependence, and impulsivity was associated with higher rates of antisocial personality disorder and cocaine and alcohol dependence. Finally, a low personality risk subtype demonstrated lower lifetime rates of substance dependence and psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Obituary: James Earle Deese (1921–1999).

Memorializes James Earle Deese, a distinguished contributor to experimental psychology, psycholinguistics, and the study of ideas. Early efforts included his book The Psychology of Learning, published in 1952. By the end of the 1950s he was deeply immersed in the study of verbal behavior in humans. His later work dealt more with the history of ideas than with psychology as an experimental science. Deese's books and articles on the structure of associations and psycholinguistics are viewed as seminal, helping to move psychology from the era of verbal learning to the modern study of verbal behavior and an investigation of the structure among associations that words stimulate or imply. (PsycINFO Database Record (c) 2010 APA, all rights reserved)