Transmission parameters of the 2001 foot and mouth epidemic in Great Britain.

Despite intensive ongoing research, key aspects of the spatial-temporal evolution of the 2001 foot and mouth disease (FMD) epidemic in Great Britain (GB) remain unexplained. Here we develop a Markov Chain Monte Carlo (MCMC) method for estimating epidemiological parameters of the 2001 outbreak for a range of simple transmission models. We make the simplifying assumption that infectious farms were completely observed in 2001, equivalent to assuming that farms that were proactively culled but not diagnosed with FMD were not infectious, even if some were infected. We estimate how transmission parameters varied through time, highlighting the impact of the control measures on the progression of the epidemic. We demonstrate statistically significant evidence for assortative contact patterns between animals of the same species. Predictive risk maps of the transmission potential in different geographic areas of GB are presented for the fitted models

OpenForensics:a digital forensics GPU pattern matching approach for the 21st century

Pattern matching is a crucial component employed in many digital forensic (DF) analysis techniques, such as file-carving. The capacity of storage available on modern consumer devices has increased substantially in the past century, making pattern matching approaches of current generation DF tools increasingly ineffective in performing timely analyses on data seized in a DF investigation. As pattern matching is a trivally parallelisable problem, general purpose programming on graphic processing units (GPGPU) is a natural fit for this problem. This paper presents a pattern matching framework - OpenForensics - that demonstrates substantial performance improvements from the use of modern parallelisable algorithms and graphic processing units (GPUs) to search for patterns within forensic images and local storage devices

Distributed resource discovery using a context sensitive infrastructure

Distributed Resource Discovery in a World Wide Web environment using full-text indices will never scale. The distinct properties of WWW information (volume, rate of change, topical diversity) limits the scaleability of traditional approaches to distributed Resource Discovery. An approach combining metadata clustering and query routing can, on the other hand, be proven to scale much better. This paper presents the Content-Sensitive Infrastructure, which is a design building on these results. We also present an analytical framework for comparing scaleability of different distribution strategies

The effect of real workloads and stochastic workloads on the performance of allocation and scheduling algorithms in 2D mesh multicomputers

The performance of the existing non-contiguous processor allocation strategies has been traditionally carried out by means of simulation based on a stochastic workload model to generate a stream of incoming jobs. To validate the performance of the existing algorithms, there has been a need to evaluate the algorithms' performance based on a real workload trace. In this paper, we evaluate the performance of several well-known processor allocation and job scheduling strategies based on a real workload trace and compare the results against those obtained from using a stochastic workload. Our results reveal that the conclusions reached on the relative performance merits of the allocation strategies when a real workload trace is used are in general compatible with those obtained when a stochastic workload is used

Differential chemosensitivity to antifolate drugs between RAS and BRAF melanoma cells.

BACKGROUND: The importance of the genetic background of cancer cells for the individual susceptibility to cancer treatments is increasingly apparent. In melanoma, the existence of a BRAF mutation is a main predictor for successful BRAF-targeted therapy. However, despite initial successes with these therapies, patients relapse within a year and have to move on to other therapies. Moreover, patients harbouring a wild type BRAF gene (including 25% with NRAS mutations) still require alternative treatment such as chemotherapy. Multiple genetic parameters have been associated with response to chemotherapy, but despite their high frequency in melanoma nothing is known about the impact of BRAF or NRAS mutations on the response to chemotherapeutic agents. METHODS: Using cell proliferation and DNA methylation assays, FACS analysis and quantitative-RT-PCR we have characterised the response of a panel of NRAS and BRAF mutant melanoma cell lines to various chemotherapy drugs, amongst them dacarbazine (DTIC) and temozolomide (TMZ) and DNA synthesis inhibitors. RESULTS: Although both, DTIC and TMZ act as alkylating agents through the same intermediate, NRAS and BRAF mutant cells responded differentially only to DTIC. Further analysis revealed that the growth-inhibitory effects mediated by DTIC were rather due to interference with nucleotide salvaging, and that NRAS mutant melanoma cells exhibit higher activity of the nucleotide synthesis enzymes IMPDH and TK1. Importantly, the enhanced ability of RAS mutant cells to use nucleotide salvaging resulted in resistance to DHFR inhibitors. CONCLUSION: In summary, our data suggest that the genetic background in melanoma cells influences the response to inhibitors blocking de novo DNA synthesis, and that defining the RAS mutation status could be used to stratify patients for the use of antifolate drugs

Are appraisal mechanisms in the Interpretation of Intrusions Inventory distinct constructs or are they all appraisals of responsibility?

Salkovskis\u27 (1989) cognitive-behavioural model of obsessive-compulsive disorder (OCD) posits that appraisals of intrusive thoughts that lead to symptoms of OCD are those in which the person perceives him or herself to be responsible for the occurrence of the intrusion and/or the perceived catastrophic outcomes (content) associated with the unwanted thought. Since Salkovskis\u27 contribution, other cognitive theorists have acknowledged the importance of the appraisals (interpretations) of intrusive thoughts in the development and maintenance of OCD. The Obsessive Compulsive Cognitions Working Group (OCCWG) created the Interpretation of Intrusions Inventory (III), a self-report scale containing three subscales (Control of Thoughts, Importance of Thoughts, and Responsibility). Each subscale is designed to capture different types of appraisals of mental intrusions. Three hundred and seven undergraduate students at the University of Windsor completed the III. To provide an independent replication of the factor structure of the III, and to assess the hypothesis that its items are better conceptualized as representing a two-factor structure (of items that assess occurrence and content) related to responsibility appraisals, exploratory and confirmatory factor analyses were conducted. (Abstract shortened by UMI.)Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .F47. Source: Masters Abstracts International, Volume: 43-05, page: 1843. Adviser: Josee L. Jarry. Thesis (M.A.)--University of Windsor (Canada), 2004

Appraisals of importance and control of thoughts: An experimental analysis

Cognitive theory of obsessions hypothesizes that faulty appraisals of intrusive thoughts are paramount in the development and persistence of obsessive-compulsive disorder (OCD). Types of faulty appraisals include interpretations of excessive responsibility for preventing an adverse outcome (responsibility), appraisals of exaggerated personal importance (importance of thoughts), and interpretations that focus on having total control over one\u27s own thoughts (control of thoughts). Previous research suggests that importance and control of thoughts appraisals (Ferguson, Jarry, & Jackson, 2006) and beliefs (Obsessive Compulsive Cognitions Working Group, 2005) are better described as one construct. Although there are numerous experimental studies suggesting that appraisals of excessive responsibility lead to more severe OCD symptoms, only two have demonstrated this effect with importance of thoughts appraisals (Teachman, Woody, & Magee, 2006; Teachman & Clerkin, 2007), and none have experimentally examined the combined effect of importance appraisals and efforts at mental control. The present research investigates the impact of an experimental manipulation of importance appraisals and attempts at mental control on the severity of OCD associated manifestations. Participants had an unwanted mental intrusion provoked through the use of a well-established intrusive thought provocation procedure (Rachman, Shafran, Mitchell, Trant, & Teachman, 1996). Appraisals of importance were experimentally manipulated by systematically varying information given to participants about having an intrusive thought (i.e., whether it is meaningful or not). Attempts at mental control were manipulated using a thought suppression task, as suppression is a common strategy used by people in response to an intrusive thought in order to regain mental control. Results revealed that participants who were exposed to importance interpretations, and those who were not given any feedback about their intrusive thought (Control group), reported more severe dysfunctional appraisals of importance and mental control, as well as higher levels of OCD associated symptoms than did those who had their intrusive thought normalized. Participants who were instructed to exercise mental control via thought suppression did not report more severe levels of obsessive-compulsive symptoms than did those who were not given such instructions. Finally, the findings clearly suggest that psychoeducational information to normalize mental intrusions is beneficial

Detecting and deterring public computer misuse : the FRILLS project

This presentation looks at forensic readiness for local libraries in Scotland (FRILLS). FRILLS aims to develop simple, low-cost techniques to provide a basic forensic readiness regime for public access ICT facilities, in order to deter misuse of those facilities by better detection of misuse

Testicular cancer and cryptorchidism

The failure of testicular descent or cryptorchidism is the most common defect in newborn boys. The descent of the testes during development is controlled by insulin-like 3 peptide and steroid hormones produced in testicular Leydig cells, as well as by various genetic and developmental factors. While in some cases the association with genetic abnormalities and environmental causes has been shown, the etiology of cryptorchidism remains uncertain. Cryptorchidism is an established risk factor for infertility and testicular germ cell tumors (TGCT). Experimental animal models suggest a causative role for an abnormal testicular position on the disruption of spermatogenesis however the link between cryptorchidism and TGCT is less clear. The most common type of TGCT in cryptorchid testes is seminoma, believed to be derived from pluripotent prenatal germ cells. Recent studies have shown that seminoma cells and their precursor carcinoma in situ cells express a number of spermatogonial stem cell (SSC) markers suggesting that TGCTs might originate from adult stem cells. We review here the data on changes in the SSC somatic cell niche observed in cryptorchid testes of mouse models and in human patients. We propose that the misregulation of growth factors' expression may alter the balance between SSC self-renewal and differentiation and shift stem cells towards neoplastic transformation