High Performance 3D PET Reconstruction Using Spherical Basis Functions on a Polar Grid

Statistical iterative methods are a widely used method of image reconstruction in emission tomography. Traditionally, the image space is modelled as a combination of cubic voxels as a matter of simplicity. After reconstruction, images are routinely filtered to reduce statistical noise at the cost of spatial resolution degradation. An alternative to produce lower noise during reconstruction is to model the image space with spherical basis functions. These basis functions overlap in space producing a significantly large number of non-zero elements in the system response matrix (SRM) to store, which additionally leads to long reconstruction times. These two problems are partly overcome by exploiting spherical symmetries, although computation time is still slower compared to non-overlapping basis functions. In this work, we have implemented the reconstruction algorithm using Graphical Processing Unit (GPU) technology for speed and a precomputed Monte-Carlo-calculated SRM for accuracy. The reconstruction time achieved using spherical basis functions on a GPU was 4.3 times faster than the Central Processing Unit (CPU) and 2.5 times faster than a CPU-multi-core parallel implementation using eight cores. Overwriting hazards are minimized by combining a random line of response ordering and constrained atomic writing. Small differences in image quality were observed between implementations

Intensive archaeological survey of the F/H Surface Enhancement Project Area, Savannah River Site, Aiken and Barnwell Counties, South Carolina

Twelve archaeological sites and four artifact occurrences were located by intensive survey of two tracts of land for the F and H Surface Enhancement Project on the Savannah River Site, Aiken and Barnwell Counties, South Carolina. Fieldwork in the 480-acre project area included surface reconnaissance of 3.6 linear kilometers of transects, 140 shovel tests along 4.2 linear kilometers of transects, an additional 162 shovel tests at sites and occurrences, and the excavation of six l {times} 2 m test units. All but one of the sites contained artifacts of the prehistoric era; the twelfth site consists of the remains of a twentieth-century home place. The historic site and six of the prehistoric sites consist of limited and/or disturbed contexts of archaeological deposits that have little research potential and are therefore considered ineligible for nomination to the National Register of Historic Places (NRHP). The remaining five sites have sufficient content and integrity to yield information important to ongoing investigations into upland site use. These sites (38AK146, 38AK535, 38AK539, 38AK541, and 38AK543) are thus deemed eligible for nomination to the NRHP and the Savannah River Archaeological Research Program (SRARP) recommends that they be preserved through avoidance or data recovery

Quality indicators for dementia and older people nearing the end of life: A systematic review

Background: Robust quality indicators (QIs) are essential for monitoring and improving the quality of care and learning from good practice. We aimed to identify and assess QIs for the care of older people and people with dementia who are nearing the end of life and recommend QIs for use with routinely collected electronic data across care settings. // Methods: A systematic review was conducted, including five databases and reference chaining. Studies describing the development of QIs for care of older people and those with dementia nearing the end of life were included. QIs were categorized as relating to processes or outcomes, and mapped against six care domains. The psychometric properties (acceptability, evidence base, definition, feasibility, reliability, and validity) of each QI were assessed; QIs were categorized as robust, moderate, or poor. // Results: From 12,980 titles and abstracts screened, 37 papers and 976 QIs were included. Process and outcome QIs accounted for 780 (79.7%) and 196 (20.3%) of all QIs, respectively. Many of the QIs concerned physical aspects of care (n = 492, 50.4%), and very few concerned spiritual and cultural aspects of care (n = 19, 1.9%). Three hundred and fifteen (32.3%) QIs were robust and of those 220 were measurable using routinely collected electronic data. The final shortlist of 71 QIs came from seven studies. // Conclusions: Of the numerous QIs developed for care of older adults and those with dementia nearing the end of life, most had poor or moderate psychometric properties or were not designed for use with routinely collected electronic datasets. Infrastructure for data availability, combined with use of robust QIs, is important for enhancing understanding of care provided to this population, identifying unmet needs, and improving service provision

Availability and quality of publicly available health workforce data sources in Australia: a scoping review protocol.

IntroductionThe health workforce is an integral component of the healthcare system. Comprehensive, high-quality data on the health workforce are essential to identifying gaps in health service provision, as well as informing future health workforce and health services planning, and health policy. While many data sources are used in Australia for these purposes, the quality of the data sources with respect to relevance, accessibility and accuracy is not clear.Methods and analysisThis scoping review aims to identify and appraise publicly available data sources describing the Australian health workforce. The review will include any data source (eg, registry, administrative database and survey) or document reporting a data source (eg, journal article, report) on the Australian health workforce, which is publicly available and describes the characteristics of the workforce. The search will be conducted in 10 bibliographic databases and the grey literature using an iterative process. Screening of titles and abstracts will be undertaken by two investigators, independently, using Covidence software. Any disagreement between investigators will be resolved by a third investigator. Documents/data sources identified as potentially eligible will be retrieved in full text and reviewed following the same process. Data will be extracted using a customised data extraction tool. A customised appraisal tool will be used to assess the relevance, accessibility and accuracy of included data sources.Ethics and disseminationThe scoping review is a secondary analysis of existing, publicly available data sources and does not require ethics approval. The findings of this scoping review will further our understanding of the quality and availability of data sources used for health workforce and health services planning in Australia. The results will be submitted for publication in peer-reviewed journals and presented at conferences targeted at health workforce and public health topics

A new echocardiographic model for quantifying three-dimensional endocardial surface area

A new technique for quantitatively mapping the three-dimensional left ventricular endocardial surface was developed, using measurements from standard cross-sectional echocardiographic images. To validate the accuracy of this echocardiographic mapping technique in an animal model, the endocardial areas of 15 excised canine ventricles were calculated using measurements made from echocardiographic studies of the hearts and compared with areas determined with latex casts of the same ventricles. Close correlation (r = 0.87, p < 0.001) between these two measures of endocardial area provided preliminary confirmation of the accuracy of the maps.To further characterize the mapping algorithm, it was translated into computer format and used to map the surfaces of idealized hemiellipsoids. Areas measured with this mapping technique closely approximated the actual areas of idealized surfaces with a wide spectrum of shapes; maps were particularly accurate for ellipsoids with shapes similar to those of undistorted human ventricles. Also, the accuracies of area calculations were relatively insensitive to deviation from the assumed positions of the echocardiographic short-axis planes. Finally, although the accuracy of the mapping technique improved as data from more transverse planes were added, the procedure proved reliable for estimating surface areas when data from only three planes were used. These studies confirm the accuracy of the echocardiographic mapping technique, and they suggest that the resulting planar plots might be useful as templates for localizing and quantifying the overall extent of abnormal wall motion

On a Watson-like Uniqueness Theorem and Gevrey Expansions

We present a maximal class of analytic functions, elements of which are in one-to-one correspondence with their asymptotic expansions. In recent decades it has been realized (B. Malgrange, J. Ecalle, J.-P. Ramis, Y. Sibuya et al.), that the formal power series solutions of a wide range of systems of ordinary (even non-linear) analytic differential equations are in fact the Gevrey expansions for the regular solutions. Watson's uniqueness theorem belongs to the foundations of this new theory. This paper contains a discussion of an extension of Watson's uniqueness theorem for classes of functions which admit a Gevrey expansion in angular regions of the complex plane with opening less than or equal to (\frac \pi k,) where (k) is the order of the Gevrey expansion. We present conditions which ensure uniqueness and which suggest an extension of Watson's representation theorem. These results may be applied for solutions of certain classes of differential equations to obtain the best accuracy estimate for the deviation of a solution from a finite sum of the corresponding Gevrey expansion.Comment: 18 pages, 4 figure

Creative and Stylistic Devices Employed by Children During a Storybook Narrative Task: A Cross-Cultural Study

Purpose: The purpose of this study was to analyze the effects of culture on the creative and stylistic features children employ when producing narratives based on wordless picture books. Method: Participants included 60 first- and second-grade African American, Latino American, and Caucasian children. A subset of narratives based on wordless picture books collected as part of a larger study was coded and analyzed for the following creative and stylistic conventions: organizational style (topic centered, linear, cyclical), dialogue (direct, indirect), reference to character relationships (nature, naming, conduct), embellishment (fantasy, suspense, conflict), and paralinguistic devices (expressive sounds, exclamatory utterances). Results: Many similarities and differences between ethnic groups were found. No significant differences were found between ethnic groups in organizational style or use of paralinguistic devices. African American children included more fantasy in their stories, Latino children named their characters more often, and Caucasian children made more references to the nature of character relationships. Conclusion: Even within the context of a highly structured narrative task based on wordless picture books, culture influences children’s production of narratives. Enhanced understanding of narrative structure, creativity, and style is necessary to provide ecologically valid narrative assessment and intervention for children from diverse cultural backgrounds

Priorities and opportunities for palliative and end of life care in United Kingdom health policies: a national documentary analysis.

BACKGROUND: Access to high-quality palliative care is inadequate for most people living and dying with serious illness. Policies aimed at optimising delivery of palliative and end of life care are an important mechanism to improve quality of care for the dying. The extent to which palliative care is included in national health policies is unknown. We aimed to identify priorities and opportunities for palliative and end of life care in national health policies in the UK. METHODS: Documentary analysis consisting of 1) summative content analysis to describe the extent to which palliative and end of life care is referred to and/or prioritised in national health and social care policies, and 2) thematic analysis to explore health policy priorities that are opportunities to widen access to palliative and end of life care for people with serious illness. Relevant national policy documents were identified through web searches of key government and other organisations, and through expert consultation. Documents included were UK-wide or devolved (i.e. England, Scotland, Northern Ireland, Wales), health and social care government strategies published from 2010 onwards. RESULTS: Fifteen policy documents were included in the final analysis. Twelve referred to palliative or end of life care, but details about what should improve, or mechanisms to achieve this, were sparse. Policy priorities that are opportunities to widen palliative and end of life care access comprised three inter-related themes: (1) integrated care - conceptualised as reorganisation of services as a way to enable improvement; (2) personalised care - conceptualised as allowing people to shape and manage their own care; and (3) support for unpaid carers - conceptualised as enabling unpaid carers to live a more independent lifestyle and balance caring with their own needs. CONCLUSIONS: Although information on palliative and end of life care in UK health and social care policies was sparse, improving palliative care may provide an evidence-based approach to achieve the stated policy priorities of integrated care, personalised care, and support for unpaid carers. Aligning existing evidence of the benefits of palliative care with the three priorities identified may be an effective mechanism to both strengthen policy and improve care for people who are dying

Eliciting a predatory response in the eastern corn snake (Pantherophis guttatus) using live and inanimate sensory stimuli: implications for managing invasive populations

North America's Eastern corn snake (Pantherophis guttatus) has been introduced to several islands throughout the Caribbean and Australasia where it poses a significant threat to native wildlife. Invasive snake control programs often involve trapping with live bait, a practice that, as well as being costly and labour intensive, raises welfare and ethical concerns. This study assessed corn snake response to live and inanimate sensory stimuli in an attempt to inform possible future trapping of the species and the development of alternative trap lures. We exposed nine individuals to sensory cues in the form of odour, visual, vibration and combined stimuli and measured the response (rate of tongue-flick [RTF]). RTF was significantly higher in odour and combined cues treatments, and there was no significant difference in RTF between live and inanimate cues during odour treatments. Our findings suggest chemical cues are of primary importance in initiating predation and that an inanimate odour stimulus, absent of simultaneous visual and vibratory cues, is a potential low-cost alternative trap lure for the control of invasive corn snake populations