We present the design for OpenPET, an electronics readout system designed for prototype radiotracer imaging instruments. The critical requirements are that it has sufficient performance, channel count, channel density, and power consumption to service a complete camera, and yet be simple, flexible, and customizable enough to be used with almost any detector or camera design. An important feature of this system is that each analog input is processed independently. Each input can be configured to accept signals of either polarity as well as either differential or ground referenced signals. Each signal is digitized by a continuously sampled ADC, which is processed by an FPGA to extract pulse height information. A leading edge discriminator creates a timing edge that is "time stamped" by a TDC implemented inside the FPGA. This digital information from each channel is sent to an FPGA that services 16 analog channels, and information from multiple channels is processed by this FPGA to perform logic for crystal lookup, DOI calculation, calibration, etc. As all of this processing is controlled by firmware and software, it can be modified / customized easily. The system is open source, meaning that all technical data (specifications, schematics and board layout files, source code, and instructions) will be publicly available.

The ideal psoralen-ultraviolet A (PUVA) regimen for chronic plaque psoriasis has yet to be established. There are four components to a PUVA regimen: the dose of psoralen, the starting dose of UVA, the frequency of treatment and the incremental UVA dose protocol. Recent studies have been directed at trying to optimize the efficacy of PUVA while minimizing acute side-effects and the risk of cutaneous carcinogenesis, believed to be independently related to the cumulative dose of UVA and the total number of treatments. The British Photodermatology Group recommends two twice-weekly PUVA regimens: one starts with 50% of the minimal phototoxic dose (MPD) and uses weekly increments of 40%, 30%, 25%, 20%, 15%, 10% and 5% of the previous dose to a maximum of 14.5 J/cm2; the other starts with a fixed dose based on skin type and uses weekly dose increments of 40%, decreasing to 20% once erythema develops. We undertook a prospective randomized controlled trial comparing these regimens in 85 Irish patients. The clearance rate with the MPD regimen was lower than with the skin type regimen, 67.5% vs. 95% (P < 0.05). The reasons for treatment failure were grade 3 erythema and severe PUVA itch. There was a trend suggesting that patients with skin types I and II, but not skin type III, required a higher cumulative UVA dose and fewer exposures to clear with the MPD regimen than the skin type regimen, although this did not reach statistical significance. Grades 2 or 3 erythema were very common in both treatment groups (52. 5% of the skin type group and 45% of the MPD group). This is the third study to suggest that patients with skin types I and II receive a higher total UVA dose when the starting dose is 50-70% of the MPD (rather than 0.5 J/cm2 for skin type I and 1.0 J/cm2 for skin type II) and when large dose increments are used. We suggest that smaller dose increments should be used in patients with skin types I and II.

Child protection social work in Ireland has been expanding at a significant pace over the past decade, particularly since the implementation of the 1991 Child Care Act and the emergence of a number of child abuse ‘scandals’ since the early 1990s. One health board area in Ireland, itself subject to one of the most controversial child abuse inquiries, commissioned a research study into the nature of child protection practices in the area. The aim of the research was to evaluate the overall child protection system and to consider what impact, if any, new practice guidelines and procedures, implemented in the aftermath of the inquiry, had made on the service. This paper considers some of the key findings from the research and considers these in the context of the overall Irish child protection system. Three particular aspects of the research are focused on: the use of procedures and guidelines, the nature of interagency cooperation and the position of social workers within this, and the overall nature and direction of the child care system.

Typically, IT projects are delivered over-budget and behind schedule. In this paper, we explore the effects of common project management practices that contribute to these problems and suggest a better alternative that can utilize resources more effectively. Our alternative approach uses (a) a thorough analysis of risks affecting activities in a project plan (i.e., the root factors leading to cost and time overruns), and (b) an optimization of the resources allocated to each activity in the project plan to maximize the probability of on time and within budget project completion. One key feature of our method is its capability to adapt and learn the risk factors affecting activities during the course of the project, enabling project managers to reallocate resources dynamically to ensure a better outcome given the updated risk profile. We use simulations to test the performance of our optimization algorithm and to gain insights into the benefits of adaptive re-planning.

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