Binding ties: Closeness and conflict in adult children's caregiving relationships.

The authors used a path model to test the hypothesis that emotional closeness and conflict between adult–child caregivers (N?=?90) and their impaired parents mediated the impact of the parents' functional and cognitive impairment on the caregivers' subjective stress, subjective effectiveness, and depression. Closeness mediated the relationship between cognitive impairment and both stress and effectiveness, whereas conflict mediated cognitive impairment for all 3 outcomes and generally accounted for more variance. There was limited evidence that functional impairment was mediated by the quality of the relationship. Results highlight the importance of both positive and negative ties as intervening mechanisms influencing caregivers' well-being, especially in the presence of cognitive dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Longitudinal patterns of risk for depression in dementia caregivers: Objective and subjective primary stress as predictors.

The present study examined how patterns of risk for depression over 1 year in 188 dementia caregivers (consistently asymptomatic, n ?=?88; consistently symptomatic, n ?=?40; changing risk, n ?=?60) could be predicted by objective (behavior problems of the relative) and subjective (role captivity and overload) primary stress. Results reveal that all primary stressors differentiated caregivers who remained at low levels of symptomatology over the course of 1 year from those who were at risk for experiencing a depressive disorder. In addition, caregivers' subjective experience of role captivity predicted the chronicity of risk. Findings extend prior caregiving research on patterns of depressive symptomatology by highlighting the relationship between subjective primary stressors and stability and change in caregivers' mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of Ectopic Beats in the Electrocardiogram Using an Auto-Associative Neural Network

Abnormal rhythms of the heart are often preceded by the occurrence of ectopic beats. These are difficult to detect as their shape is not very different from that of a normal QRS complex, the main feature in the electrocardiogram. We show how an auto-asociative multi-layer perceptron can be trained to detect normal beats only, so that the subtle abnormalities in shape of ectopic beats become clearly identifiable. This is a generic detector of abnormal beats (i.e. beats whose morphology is different from that of a normal beat) and we use ventricular ectopic beats to illustrate the performance of the algorithm. We also propose a new parameter, the variance ratio, to monitor the progress of learning in an auto-associative network.     

More on graph theoretic software watermarks: Implementation,analysis, and attacks

This paper presents an implementation of the watermarking method proposed by Venkatesan et al. in their paper [R. Venkatesan, V. Vazirani, S. Sinha, A graph theoretic approach to software watermarking, in: Fourth International Information Hiding Workshop, Pittsburgh, PA, 2001]. An executable program is marked by the addition of code for which the topology of the control-flow graph encodes a watermark. We discuss issues that were identified during construction of an actual implementation that operates on Java bytecode. We present two algorithms for splitting a watermark number into a redundant set of pieces and an algorithm for turning a watermark number into a control-flow graph. We measure the size and time overhead of watermarking, and evaluate the algorithm against a variety of attacks.     

A level set topology optimization method for the buckling of shell structures

Structural and Multidisciplinary Optimization - Shell structures are some of the most widely used in engineering applications. Flat plates, stiffened panels, and wing ribs are each examples of...     

Glutathione Conjugation and DANN Adduct Formation of Diol Epoxides in V79 Cells Expressing Human Glutathione Transferase P1-1

V79 cells and cells over-expressing glutathione transferase (GST) P1-1 have been incubated with the (+)- and (?)-anti?enantiomers of trans?7,8-dihydroxy-9,10-epoxy- 7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) and trans?9,10-dihydroxy-11,12-epoxy-9,10,11,12-tetrahydrobenzo[c]chrysene (BCDE) and the formation of glutathione (GSH) conjugates and DNA adducts monitored. With (+)-anti?BPDE and (?)-anti?BCDE, the results demonstrate a several fold increase in conjugate formation concomitant with reduced levels of DNA adducts in GST expressing cells relative to control cells. Thus, the effects were restricted to the enantiomers with R?absolute configuration at the benzylic oxirane carbon. The rate of conjugate formation of BCDE relative to BPDE is significantly lower indicating reduced accessibility of the more lipophilic BCDE for GSTP1-1.     

Multi-user Quantum Cryptography on Optical Networks

Abstract

Quantum cryptography has been shown to be an effective technology for the secure distribution of keys on point-to-point optical links. We show how the existing techniques can be extended to allow multi-user secure key distribution on optical networks. We demonstrate that using network configurations typical of those found in passive optical network architectures any of the current quantum key distribution protocols can be adapted to implement secure key distribution from any user to any other user. An important feature of these adapted protocols is that the broadcaster, or service provider on the network, does not have to be trusted by the two users who wish to establish a key.     

A new interpretation of depth-age profiles

Dosimetry and other techniques provide depth-age profiles in materials as diverse as sediments and ice. A frequent characteristic feature of these plots is a non-linear curve with a foreshortened depth scale. Whilst the age analyses from the dosimetry do not present a problem, many authors have made subsequent assumptions on the basis of the curve shape with respect to climate and environmental changes. Such claims should be strongly questioned, as by using a model which includes the effects of compaction, most of the original curves transform into linear plots corresponding to constant depositional rates. The corrections and the implications for models of climate change are discussed.     

An analysis of a puncture wound case with medical intervention

A worker noted a small wound to his thumb when leaving a work site that was undergoing decontamination because of past operations with plutonium (Pu) and americium (Am). Direct surveys of the wound site confirmed the presence of contamination. The chelating agent Ca-DTPA was administered via a nebuliser within an hour after discovery of the wound. External measurements were made of the wound site and wound dressings; 24-h urinary excretion data were collected periodically and the Pu and Am urine content was determined. Zn-DTPA was administered on three occasions. The ICRP Pu systemic model was modified to consider the enhanced urinary excretion following administration of the chelating agents. The analysis indicated that the wound resulted in an initial deposition of 400 Bq 238Pu, 2240 Bq (239/240)Pu and 1060 Bq 241Am. About 70% of the initial wound activity was removed by surgical procedures and less than 1% of the wound activity was removed by chelation therapy. This paper compares the observed urinary excretion data with that indicated by a simulation of the kinetics of the transfer from the wound site and the kinetics of the chelating agent and Pu.     

Implication of chromium speciation on disposal of discarded CCA-treated wood

The wood preservative chromated copper arsenate (CCA) contains hexavalent chromium [Cr(VI)] and the conversion of Cr(VI) to trivalent chromium [Cr(III)] drives fixation of the treatment chemicals to the wood fibers. Since the toxicity of Cr depends on its valence state, an assessment of the Cr species occurring in CCA-treated wood, as well as leachates and ashes from CCA-treated wood, is helpful when assessing implications for disposal. In this study, both new and weathered wood samples of CCA-treated wood and their ashes were evaluated for total Cr and Cr(VI) within the solid matrices and within leachates. Results show that for both new and weathered CCA-treated wood, Cr(VI) occurred in the range of 0.7-4% of the total Cr. Greater Cr leaching occurred at the pH extremes, with Cr(VI) only measured under alkaline pH values (pH > 9.0). Total chromium concentrations from synthetic precipitation leaching procedure (SPLP) leachates from CCA-treated wood were consistently less than 3mg/L with Cr(VI) below detection limits. The results suggest that leaching of Cr(VI) from discarded CCA-treated wood should not be a concern in most landfill environments. One exception would be disposal in landfills with alkaline leachate; Cr(VI) was observed to leach from CCA-treated wood in the presence of alkaline leachate from crushed concrete. When CCA-treated wood is combusted, chromium becomes concentrated in the ash. Cr(VI) in ash from the combustion of CCA-treated wood was found between 4 and 7% of the total chromium. In ash from the combustion of wood recovered from construction and demolition (C&D) debris (which contained some CCA-treated wood), Cr(VI) accounted for as much as 43% of the total Cr. Nearly, all of the Cr in SPLP leachates produced from the ash was in the Cr(VI) form. The degree of Cr(VI) leaching from the ash was highly dependent upon the alkalinity of the ash, with higher ash leachate pH resulting in greater concentrations of Cr(VI).