Effects of various, shape parameters on packing of aggregate particles

The shape of the aggregate particles used has significant effects on the properties of the concrete produced. One major effect is on the packing density of the aggregate which determines the amount of cement paste needed to fill the voids between the aggregate particles. In order to study how the various shape parameters of aggregate particles would affect the packing of aggregate, aggregate samples of different rock types from different sources have been analysed for their shape characteristics using a newly developed digital image processing technique and their packing densities measured in accordance with an existing method given in the British Standard. The packing densities of the aggregate samples are correlated to the shape parameters to evaluate the effects of the various shape parameters on packing. From the results of the correlation, it is found that the shape factor and the convexity ratio are the most important shape parameters affecting the packing of an aggregate. Two alternative formulas revealing the combined effects of these two shape parameters on the packing density of aggregate are proposed.published_or_final_versio

Temporal Construal Effects Are Independent of Episodic Future Thought

Human thought is prone to biases. Some biases serve as beneficial heuristics to free up limited cognitive resources or improve well-being, but their neurocognitive basis is unclear. One such bias is a tendency to construe events in the distant future in abstract, general terms and events in the near future in concrete, detailed terms. Temporal construal may rely on our capacity to orient toward and/or imagine context-rich future events. We tested 21 individuals with impaired episodic future thinking resulting from lesions to the hippocampus or ventromedial prefrontal cortex (vmPFC) and 57 control participants (aged 45-76 years) from Canada and Italy on measures sensitive to temporal construal. We found that temporal construal persisted in most patients, even those with impaired episodic future thinking, but was abolished in some vmPFC cases, possibly in relation to difficulties forming and maintaining future intentions. The results confirm the fractionation of future thinking and that parts of vmPFC might critically support our ability to flexibly conceive and orient ourselves toward future events

Protecting digital legal professional privilege LPP data

The Best Paper AwardTo enable free communication between legal advisor and his client for proper functioning of the legal system, certain documents, known as Legal professional privilege (LPP) documents, can be excluded as evidence for prosecution. In physical world, protection of LPP information is well addressed and proper procedure for handling LPP articles has been established. However, there does not exist a forensically sound procedure for protecting 'digital' LPP information. In this paper, we try to address this important, but rarely addressed, issue. We point out the difficulties of handling digital LPP data and discuss the shortcomings of the current practices, then we propose a feasible procedure for solving this problem. © 2008 IEEE.published_or_final_versionThe 3rd International Workshop on Systematic Approaches to Digital Forensic Engineering (IEEE/SADFE 2008), Oakland, CA., 22 May 2008. In Proceedings of the 3rd SADFE, 2008, p. 91-10

Antecedent Avian Immunity Limits Tangential Transmission of West Nile Virus to Humans

Background: West Nile virus (WNV) is a mosquito-borne flavivirus maintained and amplified among birds and tangentially transmitted to humans and horses which may develop terminal neuroinvasive disease. Outbreaks typically have a three-year pattern of silent introduction, rapid amplification and subsidence, followed by intermittent recrudescence. Our hypothesis that amplification to outbreak levels is contingent upon antecedent seroprevalence within maintenance host populations was tested by tracking WNV transmission in Los Angeles, California from 2003 through 2011. Methods: Prevalence of antibodies against WNV was monitored weekly in House Finches and House Sparrows. Tangential or spillover transmission was measured by seroconversions in sentinel chickens and by the number of West Nile neuroinvasive disease (WNND) cases reported to the Los Angeles County Department of Public Health. Results: Elevated seroprevalence in these avian populations was associated with the subsidence of outbreaks and in the antecedent dampening of amplification during succeeding years. Dilution of seroprevalence by recruitment resulted in the progressive loss of herd immunity following the 2004 outbreak, leading to recrudescence during 2008 and 2011. WNV appeared to be a significant cause of death in these avian species, because the survivorship of antibody positive birds significantly exceeded that of antibody negative birds. Cross-correlation analysis showed that seroprevalence was negatively correlated prior to the onset of human cases and then positively correlated, peaking at 4–6 weeks after the onse

The counselling self-estimate inventory (COSE): Does it work in Chinese counsellors?

Counselling self-efficacy is an important construct for research and evaluation in counsellors' competencies and training effectiveness. Larson et al. developed the Counselling Self-Estimate Inventory (COSE) for counsellors in America and examined its factor structure using exploratory factor analysis. They recommended a five-factor model (microskills, counselling process, difficult client behaviour, cultural competence, and awareness of values) and the use of the COSE for future research. However, little research has investigated the validity of the COSE in the context of counselling Chinese students in schools. In the present study, the factor structure of responses to the Chinese version of the Counselling Self-Estimate Inventory in a sample of 578 Hong Kong secondary school guidance teachers was examined using the EQS approach to confirmatory factor analysis. The results showed that while a five-factor model was fairly able to fit the data, the deletion of items related to the awareness of values factor yielded a better fitting model. The discussion of potential uses and limitations of the C-COSE in the context of preparing and supervising school guidance personnel in student counselling is relevant to counselling psychologists and researchers in Hong Kong and other parts of the world.postprin

Identification of Mechanosensitive Genes during Embryonic Bone Formation

Although it is known that mechanical forces are needed for normal bone development, the current understanding of how biophysical stimuli are interpreted by and integrated with genetic regulatory mechanisms is limited. Mechanical forces are thought to be mediated in cells by “mechanosensitive” genes, but it is a challenge to demonstrate that the genetic regulation of the biological system is dependant on particular mechanical forces in vivo. We propose a new means of selecting candidate mechanosensitive genes by comparing in vivo gene expression patterns with patterns of biophysical stimuli, computed using finite element analysis. In this study, finite element analyses of the avian embryonic limb were performed using anatomically realistic rudiment and muscle morphologies, and patterns of biophysical stimuli were compared with the expression patterns of four candidate mechanosensitive genes integral to bone development. The expression patterns of two genes, Collagen X (ColX) and Indian hedgehog (Ihh), were shown to colocalise with biophysical stimuli induced by embryonic muscle contractions, identifying them as potentially being involved in the mechanoregulation of bone formation. An altered mechanical environment was induced in the embryonic chick, where a neuromuscular blocking agent was administered in ovo to modify skeletal muscle contractions. Finite element analyses predicted dramatic changes in levels and patterns of biophysical stimuli, and a number of immobilised specimens exhibited differences in ColX and Ihh expression. The results obtained indicate that computationally derived patterns of biophysical stimuli can be used to inform a directed search for genes that may play a mechanoregulatory role in particular in vivo events or processes. Furthermore, the experimental data demonstrate that ColX and Ihh are involved in mechanoregulatory pathways and may be key mediators in translating information from the mechanical environment to the molecular regulation of bone formation in the embryo

Recommendations for the treatment of epilepsy in adult patients in general practice in Belgium: an update

In 2008, a group of Belgian epilepsy experts published recommendations for antiepileptic drug (AED) treatment of epilepsies in adults and children. Selection of compounds was based on the registration and reimbursement status in Belgium, the level of evidence for efficacy, common daily practice and the personal views and experiences of the authors. In November 2011 the validity of these recommendations was reviewed by the same group of Belgian epilepsy experts who contributed to the preparation of the original paper. The recommendations made in 2008 for initial monotherapy in paediatric patients were still considered to be valid, except for the first choice treatment for childhood absence epilepsy. This update therefore focuses on the treatment recommendations for initial monotherapy and add-on treatment in adult patients. Several other relevant aspects of treatment with AEDs are addressed, including considerations for optimal combination of AEDs (rational polytherapy), pharmacokinetic properties, pharmacodynamic and pharmacokinetic interaction profile, adverse effects, comorbidity, treatment of elderly patients, AED treatment during pregnancy, and generic substitution of AEDs