A Bayesian Image Analysis of the Change in Tumor/Brain Contrast Uptake Induced by Radiation via Reversible Jump Markov Chain Monte Carlo

This work is motivated by a pilot study on the change in tumor/brain contrast uptake induced by radiation via quantitative Magnetic Resonance Imaging. The results inform the optimal timing of administering chemotherapy in the context of radiotherapy. A noticeable feature of the data is spatial heterogeneity. The tumor is physiologically and pathologically distinct from surrounding healthy tissue. Also, the tumor itself is usually highly heterogeneous. We employ a Gaussian Hidden Markov Random Field model that respects the above features. The model introduces a latent layer of discrete labels from an Markov Random Field (MRF) governed by a spatial regularization parameter. We further assume that conditional on the hidden labels, the observed data are independent and normally distributed, We treat the regularization parameter of the MRF, as well as the number of states of the MRF as parameters, and estimate them via the Reversible Jump Markov chain Monte Carlo algorithm. We propose a novel and nontrivial implementation of the Reversible Jump moves. The performance of the method is examined in both simulation studies and real data analysis. We report the pixel-wise posterior mean and standard deviation of the change in contrast uptake marginalized over the number of states and hidden labels. We also compare the performance with a Markov chain with fixed number of states and a parallel Expectation-Maximization approach from a frequentist perspective

Design and analysis of permanent magnet synchronous motors

The latest developments in high energy product permanent magnet materials have led to renewed interest in the permanent magnet (P.M.) synchronous motor. This is primarily due to the high efficiencies and power factors which may be obtained from the P.M. motor. If this device is to find its way into widespread industrial use, it is important that sufficient analytical skills be developed and detailed design information be transmitted to the motor design engineer, such that the inherent advantages of a P.M. motor are recognized and utilized. -- This work, then, presents a detailed analysis of both the transient and steady state behavior of the P.M. motor. Included, as well, are the derivations of three of the important parameters of P.M. motors, namely direct axis reactance, quadrature axis reactance and open circuit voltage. The analysis is then used to predict transient and steady state performance with reasonable accuracy. Tested results of four prototype P.M. motors are presented in order to provide correlation with, and verification of, the analytical results. -- Finally, a number of important parameter variations are undertaken, and important conclusions to the design, manufacture and testing of P.M. motors are presented

Longitudinal Image Analysis of Tumor/Brain Change in Contrast Uptake Induced by Radiation

This work is motivated by a quantitative Magnetic Resonance Imaging study of the differential tumor/healthy tissue change in contrast uptake induced by radiation. The goal is to determine the time in which there is maximal contrast uptake, a surrogate for permeability, in the tumor relative to healthy tissue. A notable feature of the data is its spatial heterogeneity. Zhang, Johnson, Little, and Cao (2008a and 2008b) discuss two parallel approaches to “denoise” a single image of change in contrast uptake from baseline to a single follow-up visit of interest. In this work we explore the longitudinal profile of the tumor/healthy tissue change in contrast uptake. In addition to the spatial correlation, we account for temporal correlation by jointly modeling multiple images on the individual subjects over time. We fit a two-stage model. First, we propose a longitudinal image model for each subject. This model simultaneously accounts for the spatial and temporal correlation and denoises the observed images by borrowing strength both across neighboring pixels and over time. We propose to use the area under the receiver operating characteristics (ROC) curve (AUC) to summarize the differential contrast uptake between tumor and healthy tissue. In the second stage, we fit a population model on the AUC values and estimate when it achieves the maximum

Arkansas Agricultural Chemical Ground-Water Management Plan

The Arkansas Agricultural Chemical Ground-Water Management Plan (SMP) is based on the Draft State Pesticide Ground- Water Management Plan Guidance and The Pesticides and Ground-Water Protection Strategy prepared by the U.S. Environmental Protection Agency (EPA). The need for a plan to protect ground water from contamination by agricultural chemicals and agents arises from evidence nationwide that using these chemicals can, in some instances, lead to contamination. In February 1988, EPA proposed a strategy to regulate certain pesticides by prohibiting their use in areas vulnerable to leaching unless a state develops and implements an acceptable management plan. The advantage of a state plan as opposed to a federal plan is that a state plan can provide protection for ground-water resources without unnecessarily restricting pesticide use. State plans can be more sensitive to local conditions such as soil types, farming practices and hydrogeological considerations

Successful Piloting of Discrete ISS at a CCR Impoundment

Successful Piloting of Discrete ISS at a CCR Impoundment Authors Mr. George Little - United States - Forgen Dr. Paul Lear - United States - Lear Environmental Consulting Mr. Tim Silar - United States - Silar Services Mr. Richard Chapman - United States - Forgen Mr. John Magee - United States - Silar Services Mr. Ambaresh Tijare - United States - Forgen Mr. David Miller - United States - Forgen Abstract Discrete ISS involves targeted stabilization treatment in a discrete treatment zone. Rather than treating overburden, the mixing auger injects water and/or air as a drilling fluid until the top of the treatment zone is reached. Reagent grout is then injected as the mixing auger moves through the treatment zone. For CCR impoundments, Discrete ISS offers the ability to produce a low permeability treated zone underneath the CCR material, hydraulically isolating it from groundwater. Forgen conducted pilot testing at a CCR impoundment in the Summer of 2022 under the direction of Silar Services Incorporated (SSi), the discrete ISS technology patent holder. In three areas of the impoundment, Forgen successfully drilled through 25 to 45 feet of CCR material and stabilized a 4 to 5-foot thick layer of ash and underlying native soil. A rosette of 7 columns was installed in each of the 3 areas. Logs were generated for each column by the drill rig monitoring system, including the inclination of the Kelly bar/drill shaft (via x and y inclinometers) and the horizontal location (northing and easting) of the mixing head tip logged continuously throughout the advancement of the auger at each column location. The logs allowed Forgen to demonstrate that complete overlap was achieved between adjacent columns. Combined with the QC results for collected wet grab samples and post-treatment core samples, Forgen was able to demonstrate that the treatment zone was emplaced at the planned top and bottom elevations and that the hydraulic conductivity of the treated material was less than 1x10-6 cm/s. The pilot study results indicate that a low permeability layer can be installed underneath the CCR material in the impoundment

An Epidemiological Reappraisal of the Familial Aggregation of Prostate Cancer: A Meta-Analysis

Studies on familial aggregation of cancer may suggest an overall contribution of inherited genes or a shared environment in the development of malignant disease. We performed a meta-analysis on familial clustering of prostate cancer. Out of 74 studies reporting data on familial aggregation of prostate cancer in unselected populations retrieved by a Pubmed search and browsing references, 33 independent studies meeting the inclusion criteria were used in the analysis performed with the random effects model. The pooled rate ratio (RR) for first-degree family history, i.e. affected father or brother, is 2.48 (95% confidence interval: 2.25–2.74). The incidence rate for men who have a brother who got prostate cancer increases 3.14 times (CI:2.37–4.15), and for those with affected father 2.35 times (CI:2.02–2.72). The pooled estimate of RR for two or more affected first-degree family members relative to no history in father and in brother is 4.39 (CI:2.61–7.39). First-degree family history appears to increase the incidence rate of prostate cancer more in men under 65 (RR:2.87, CI:2.21–3.74), than in men aged 65 and older (RR:1.92, CI:1.49–2.47), p for interaction = 0.002. The attributable fraction among those having an affected first-degree relative equals to 59.7% (CI:55.6–63.5%) for men at all ages, 65.2% (CI:57.7–71.4%) for men younger than 65 and 47.9% (CI:37.1–56.8%) for men aged 65 or older. For those with a family history in 2 or more first-degree family members 77.2% (CI:65.4–85.0%) of prostate cancer incidence can be attributed to the familial clustering. Our combined estimates show strong familial clustering and a significant effect-modification by age meaning that familial aggregation was associated with earlier disease onset (before age 65)

Continental breakup and UHP rock exhumation in action: GPS results from the Woodlark Rift, Papua New Guinea

We show results from a network of campaign Global Positioning System (GPS) sites in the Woodlark Rift, southeastern Papua New Guinea, in a transition from seafloor spreading to continental rifting. GPS velocities indicate anticlockwise rotation (at 2–2.7°/Myr, relative to Australia) of crustal blocks north of the rift, producing 10–15 mm/yr of extension in the continental rift, increasing to 20–40 mm/yr of seafloor spreading at the Woodlark Spreading Center. Extension in the continental rift is distributed among multiple structures. These data demonstrate that low-angle normal faults in the continents, such as the Mai'iu Fault, can slip at high rates nearing 10 mm/yr. Extensional deformation observed in the D'Entrecasteaux Islands, the site of the world's only actively exhuming Ultra-High Pressure (UHP) rock terrane, supports the idea that extensional processes play a critical role in UHP rock exhumation. GPS data do not require significant interseismic coupling on faults in the region, suggesting that much of the deformation may be aseismic. Westward transfer of deformation from the Woodlark Spreading Center to the main plate boundary fault in the continental rift (the Mai'iu fault) is accommodated by clockwise rotation of a tectonic block beneath Goodenough Bay, and by dextral strike slip on transfer faults within (and surrounding) Normanby Island. Contemporary extension rates in the Woodlark Spreading Center are 30–50% slower than those from seafloor spreading-derived magnetic anomalies. The 0.5 Ma to present seafloor spreading estimates for the Woodlark Basin may be overestimated, and a reevaluation of these data in the context of the GPS rates is warranted

Servitization and enterprization in the construction industry:the case of a specialist subcontractor

The current economic climate and a continuing fall in output of the UK construction industry has led to falling prices and margins particularly affecting those lower down in the supply chain such as specialist subcontractors. Coen Ltd. is one such company based in the West Midlands. Faced with a need to up its game it has embarked on a business improvement programme concentrating on better operational efficiency, building stronger client relationships and delivering value added services. Lacking appropriate internal resources Coen has joined with Aston Business School in a 2 year ERDF sponsored project to fulfil the transformation programme. The paper will describe the evolution of product- service offerings in construction and link this with the work being carried out at Coen with Aston and outline the anticipated outcomes