Measurement of the Spectral Shape of the β-Decay of ^{137}Xe to the Ground State of ^{137}Cs in EXO-200 and Comparison with Theory

We report on a comparison between the theoretically predicted and experimentally measured spectra of the first-forbidden nonunique β-decay transition ^{137}Xe(7/2^{-})→^{137}Cs(7/2^{+}). The experimental data were acquired by the EXO-200 experiment during a deployment of an AmBe neutron source. The ultralow background environment of EXO-200, together with dedicated source deployment and analysis procedures, allowed for collection of a pure sample of the decays, with an estimated signal to background ratio of more than 99 to 1 in the energy range from 1075 to 4175 keV. In addition to providing a rare and accurate measurement of the first-forbidden nonunique β-decay shape, this work constitutes a novel test of the calculated electron spectral shapes in the context of the reactor antineutrino anomaly and spectral bump.

Search for Neutrinoless Double-β Decay with the Complete EXO-200 Dataset

A search for neutrinoless double-β decay (0νββ) in ^{136}Xe is performed with the full EXO-200 dataset using a deep neural network to discriminate between 0νββ and background events. Relative to previous analyses, the signal detection efficiency has been raised from 80.8% to 96.4±3.0%, and the energy resolution of the detector at the Q value of ^{136}Xe 0νββ has been improved from σ/E=1.23% to 1.15±0.02% with the upgraded detector. Accounting for the new data, the median 90% confidence level 0νββ half-life sensitivity for this analysis is 5.0×10^{25}  yr with a total ^{136}Xe exposure of 234.1 kg yr. No statistically significant evidence for 0νββ is observed, leading to a lower limit on the 0νββ half-life of 3.5×10^{25}  yr at the 90% confidence level.

DEVELOPMENTAL CORRELATES OF GENOME SIZE IN PLETHODONTID SALAMANDERS AND THEIR IMPLICATIONS FOR GENOME EVOLUTION

We present an analysis of the evolutionary relationship between genome size (C-value, mass of DNA per haploid nucleus) and developmental rate using observations of limb regeneration in salamanders of the family Plethodontidae. Rates of growth and differentiation of regenerating limbs are reported for 27 plethodontid species whose C-values range from 14 to 76 picograms. A phylogenetic analysis employing Felsenstein's method of independent contrasts indicates that rate of differentiation is inversely proportional to genome size, although we have not identified any statistically significant association between genome size and the growth rate of regenerating tissue. Our results are consistent with an interpretation that genome size may place a limit on the maximum rate of regeneration attainable in plethodontid salamanders. The implications of our findings for the "junk DNA," "nucleotypic DNA," "selfish DNA," and "skeletal DNA" hypotheses of genome evolution are discussed.

Prospective assessment of the diagnostic utility of esophageal brushings in adults with eosinophilic esophagitis

Patients with eosinophilic esophagitis (EoE) undergo multiple endoscopies with biopsy for both diagnosis and assessment of treatment response, which is inconvenient and costly. Brush cytology has been examined in Barrett's esophagus to reduce the need for repeated endoscopic biopsies. The aim of this pilot study was to evaluate the ability of brush cytology to detect mucosal eosinophilia in patients with EoE. This prospective study included adults with untreated and treated esophageal eosinophilia undergoing endoscopy at a tertiary care center. Patients received paired brushings and biopsies at the proximal and distal esophagus. A blinded pathologist quantified the number of eosinophils and epithelial cells per high-power field (hpf) on the cytology slides. The ratio of eosinophils/epithelial cells was used to normalize the cytology specimens for density of cells collected. The main outcome measures were sensitivity and specificity of brush cytology, and correlation between cytology and histology. Twenty-eight patients enrolled. The average age of the cohort was 37.7 ± 10.4 years; 75% of subjects were male. The sensitivity of cytology was 67-69% at the proximal esophagus and 70-72% at the distal esophagus. The specificity was 61-67% proximally and 70-75% distally. Histology was not significantly correlated with the max ratio of eosinophils/epithelial cells per hpf or the absolute number of eosinophils on cytology slides. Cytology using esophageal brushing has limited sensitivity and specificity for the detection of esophageal mucosal eosinophilia. The presence of exudates on endoscopy increased the detection of eosinophilia, which could make cytology useful in pediatric EoE, which often has a more exudative presentation. Diagnostic yield may improve with alternative acquisition techniques or the incorporation of eosinophil degranulation proteins.

Study on the efficiency of nanosized magnetite and mixed ferrites in magnetic hyperthermia

Magnetic materials, which have the potential for application in heating therapy by hyperthermia, were prepared. This alternative treatment is used to eliminate cancer cells. Magnetite, magnesium-calcium ferrites and manganese-calcium ferrites were synthesized by sol-gel method followed by heat treatment at different temperatures for 30 min in air. Materials with superparamagnetic behavior and nanometric sizes were obtained in all the cases. Thus, these nanopowders may be suitable for their use in human tissue. The average sizes were 14 nm for magnetite, 10 nm for both Mg(0.4)Ca(0.6)Fe(2)O(4) and Mg(0.6)Ca(0.4)Fe(2)O(4) and 11 nm for Mn(0.2)Ca(0.8)Fe(2)O(4). Taking into account that the Mg(0.4)Ca(0.6)Fe(2)O(4) and Mg(0.6)Ca(0.4)Fe(2)O(4) treated at 350 °C showed the lower coercivity values, these nanoparticles were selected for heating tests and cell viability. Heating curves of Mg(0.4)Ca(0.6)Fe(2)O(4) subjected to a magnetic field of 195 kHz and 10 kA/m exhibited a temperature increase up to 45 °C in 15 min. A high human osteosarcoma cell viability of 90-99.5% was displayed. The human osteosarcoma cell with magnesium-calcium ferrites exposed to a magnetic field revealed a death cell higher than 80% in all the cases.

Molecular phylogenetics of moray eels (Muraenidae) demonstrates multiple origins of a shell-crushing jaw (Gymnomuraena, Echidna) and multiple colonizations of the Atlantic Ocean

Moray eels (Muraenidae) are apex predators on coral reefs around the world, but they are not well studied because their cryptic habitats and occasionally aggressive behaviors make them difficult to collect. We provide a molecular phylogeny of moray eels including 44 species representing two subfamilies, eight genera, and all tropical ocean basins. Phylogenetic relationships among these taxa are estimated from portions of mitochondrial loci cytochrome b (632 bp) and cytochrome oxidase subunit 1 (596 bp), and portions of the nuclear loci RAG-1 (421 bp) and RAG-2 (754 bp). We test four sets of contrasting phylogenetic hypotheses using Bayes Factors, Shimodaira-Hasegawa tests, and Templeton tests. First, our results support the subfamily-level taxonomic distinction between true morays (Muraeninae) and snakemorays (Uropterygiinae), statistically rejecting hypotheses of non-monophyly for each subfamily. Second, we reject a monophyletic grouping of the genera Gymnomuraena and Echidna, which share a durophagous (shell-crushing) cranial morphology and dentition, indicating that the durophagous characters are not homologous. Third, we demonstrate that durophagous feeding habits and associated morphological characters have evolved in parallel in an ancestor of Gymnomuraena and at least three additional times within the genus Echidna. Finally, the tree topology indicates multiple invasions of the Atlantic from the Indo-Pacific, one of these occurring immediately prior to formation of the Isthmus of Panama approximately 2.8 MYA (million years ago) and one or two others occurring in the early to mid Miocene. Cladogenesis occurring within the Atlantic during the mid Miocene and Pliocene also contributed to moray species diversity. These data include a pair of sister species separated by the Isthmus of Panama, allowing a time-calibrated tree with an estimated crown age for Muraenidae at between 41 and 60 MYA, consistent with fossil evidence. Most lineage accumulation within morays occurred from the late Oligocene (24-27 MYA) through the Miocene (5-23 MYA) to the late Pliocene (∼ 2.5 MYA).

Multidimensional analysis of an evolving lineage

To identify the forces directing organismal evolution, a general analytical system is developed to synthesize structuralist and Darwinian traditions in an explicitly historical framework. Morphological features of lungless salamanders are examined to identify hierarchical systems of developmental and functional constraint on evolution and their interactions with processes at the genic and populational levels. Characteristic patterns of change occur repeatedly in the evolutionary history of this group.

Phylogeography of two moray eels indicates high dispersal throughout the indo-pacific

Reef fishes disperse primarily as oceanic "pelagic" larvae, and debate continues over the extent of this dispersal, with recent evidence for geographically restricted (closed) populations in some species. In contrast, moray eels have the longest pelagic larval stages among reef fishes, possibly providing opportunities to disperse over great distances. We test this prediction by measuring mitochondrial DNA (mtDNA) and nuclear DNA variation in 2 species of moray eels, Gymnothorax undulatus (N = 165) and G. flavimarginatus (N = 124), sampled at 14-15 locations across the Indo-Pacific. The mtDNA data comprise 632 bp of cytochrome b and 596 bp of cytochrome oxidase I. Nuclear markers include 2 recombination-activating loci (421 bp of RAG-1 and 754 bp of RAG-2). Analyses of molecular variance and Mantel tests indicate little or no genetic differentiation, and no isolation by distance, across 22 000 km of the Indo-Pacific. We estimate that mitochondrial genetic variation coalesces within the past about 2.3 million years (My) for G. flavimarginatus and within the past about 5.9 My for G. undulatus. Permutation tests of geographic distance on the mitochondrial haplotype networks indicate recent range expansions for some younger haplotypes (estimated within approximately 600 000 years) and episodic fragmentation of populations at times of low sea level. Our results support the predictions that the extended larval durations of moray eels enable ocean-wide genetic continuity of populations. This is the first phylogeographic survey of the moray eels, and morays are the first reef fishes known to be genetically homogeneous across the entire Indo-Pacific.

Challenges faced in implementation of a telehealth enabled chronic wound care system

INTRODUCTION

In the rural Midwest region of Western Australia (WA), wound care is a major burden on the healthcare system. Optimal wound care was found to be impeded by issues that included the involvement of multiple healthcare providers, incomplete and inconsistent documentation, and limited access to expert review. A telehealth solution was trailed in 2007.

OBJECTIVE

To describe the systemic barriers encountered in implementing a telehealth program in rural WA and to provide recommendations for future telehealth initiatives.

METHODS

This study trialled the use of a shared electronic wound imaging and reporting system in combination with an expert remote wound consultation service for the management of patients with chronic wounds in the Midwest of WA. The trial sites included rural hospital out-patient clinics, a private domiciliary nursing service, residential aged care facilities, general practices and a podiatry clinic. The implementation conformed to accepted best practice in introducing telehealth initiatives.

RESULTS

During the trial 12 sites had the relevant software installed and were able to access a central server. Although a total of 41 patients with chronic wounds were enrolled, four sites did not enroll any patients and only two sites successfully incorporated the system into regular practice. Major obstacles were workforce issues and significant delays in installing the software at some sites. Only 47% of the healthcare providers trained to use the software at the beginning of the trial were still employed when the trial ended. Prolonged periods of vacant positions at one remote clinic and an aged care facility made it impossible for the remaining providers to allocate time for using the wound care software.

CONCLUSION

The disease burden of the patient group, funding models and workforce shortages frustrated the successful adoption of an evidence based strategy that was known to improve health outcomes.

Admixture determines genetic diversity and population differentiation in the biological invasion of a lizard species

Molecular genetic analyses show that introduced populations undergoing biological invasions often bring together individuals from genetically disparate native-range source populations, which can elevate genotypic variation if these individuals interbreed. Differential admixture among multiple native-range sources explains mitochondrial haplotypic diversity within and differentiation among invasive populations of the lizard Anolis sagrei. Our examination of microsatellite variation supports the hypothesis that lizards from disparate native-range sources, identified using mtDNA haplotypes, form genetically admixed introduced populations. Furthermore, within-population genotypic diversity increases with the number of sources and among-population genotypic differentiation reflects disparity in their native-range sources. If adaptive genetic variation is similarly restructured, then the ability of invasive species to adapt to new conditions may be enhanced.

Water safety in the bush: strategies for addressing training needs in remote areas

CONTEXT

This article describes a unique, remote, water safety-training program delivered to 11 remote Australian communities during 2006-2007. The program, known as 'Water Safety in the Bush', was developed by Combined Universities Centre for Rural Health in Geraldton Western Australia in consultation with the Commonwealth Government Department of Health and Ageing, and the Royal Life Saving Society of Australia.

PROGRAM DESCRIPTION

Drowning and near drowning are major causes of childhood death and injury in rural and remote Australia, making improved water safety awareness and skills a public health priority. Water Safety in the Bush employed a flexible, community development model to meet the special requirements of remote and isolated communities. The model had three elements: coordination by a local organisation; a water safety instruction program based on a Royal Life Saving Society of Australia curriculum adapted to meet local priorities; and strategies for sustainability.

PROGRAM EVALUATION

In the delivery of the program a total of 873 children and 219 adults received swimming and water safety instruction; 47 adults and older children received first-aid training; and 38 community members became AUSTAWIM (the Australian Council for the Teaching of Swimming and Water Safety) accredited instructors. Project evaluation showed parents and community organisations were very satisfied with the program which met a real need. Parents and instructors gave evidence of children's increased skills in water safety, swimming ability, life-saving and water confidence. Training programs with greater contact hours showed greater skill gains. Sustainability strategies included accreditation of local AUSTSWIM instructors, the erection of water safety signs, sourcing of continuing funding, and the introduction of water safety theory into the school curriculum.

LESSONS LEARNED

Flexibility was the major success factor. Within the parameters of minimum guidelines, communities were encouraged to choose the timing, venue and delivery mode of the training to ensure the program was best suited to the local community. Community ownership was achieved by requiring that local organisations design and implement the projects. Designing programs that addressed local constraints ensured high participation rates. A number of challenges were also identified. Not all community organisations had the capacity to take on the coordinating role, and struggled to effectively deliver a sustainable program. Other models may be needed for these communities. Accessing appropriately qualified water safety instructors in local areas also proved difficult at several of the sites. Further, designing standardised outcome evaluation strategies that could be implemented across all participating sites was problematic.

IMPLICATIONS

Remote and isolated communities have a pressing need to gain the knowledge and skills necessary for water safety and survival. Standard training programs, which in the case of swimming and water safety instruction are generally run in two-week blocks, are often not feasible. Models for delivering training, which give resources and power to local organisations to find innovative ways to meet their priorities, build capacity and ensure high participation rates.

Measurement of nuclear transparency for the A(e,e'pi+) reaction

We have measured the nuclear transparency of the A(e,e'pi+) process in 2H, 12C, 27Al, 63Cu, and 197Au targets. These measurements were performed at the Jefferson Laboratory over a four momentum transfer squared range Q2=1.1 to 4.7 (GeV/c)2. The nuclear transparency was extracted as the super-ratio of (sigmaA/sigmaH) from data to a model of pion-electroproduction from nuclei without pi-N final-state interactions. The Q2 and atomic number dependence of the nuclear transparency both show deviations from traditional nuclear physics expectations and are consistent with calculations that include the quantum chromodynamical phenomenon of color transparency.

Multiple sources, admixture, and genetic variation in introduced anolis lizard populations

Invasive species are classically thought to suffer from reduced within-population genetic variation compared to their native-range sources due to founder effects and population bottlenecks during introduction. Reduction in genetic variation in introduced species may limit population growth, increase the risk of extinction, and constrain adaptation, hindering the successful establishment and spread of an alien species. Results of recent empirical studies, however, show higher than expected genetic variation, rapid evolution, and multiple native-range sources in introduced populations, which challenge the classical scenario of invasive-species genetics. With mitochondrial DNA (mtDNA) sequence data, we examined the molecular genetics of 10 replicate introductions of 8 species of Anolis lizards. Eighty percent of introductions to Florida and the Dominican Republic were from multiple native-range source populations. MtDNA haplotypes restricted to different geographically distinct populations in the native range of a species commonly occurred as intrapopulation polymorphisms in introduced populations. Two-thirds of introduced populations had two or more sources, and admixture elevated genetic variation in half of the introduced populations above levels typical of native-range populations. The mean pairwise sequence divergence among haplotypes sampled within introduced populations was nearly twice that within native-range populations (2.6% vs. 1.4%). The dynamics of introductions from multiple sources and admixture explained the observed genetic contrasts between native and introduced Anolis populations better than the classical scenario for most introduced populations. Elevated genetic variation through admixture occurred regardless of the mode or circumstances of an introduction. Little insight into the number of sources or amount of genetic variation in introduced populations was gained by knowing the number of physical introductions, the size of a species' non-native range, or whether it was a deliberate or accidental introduction. We hypothesize that elevated genetic variation through admixture of multiple sources is more common in biological invasions than previously thought. We propose that introductions follow a sequential, two-step process involving a reduction in genetic variation due to founder effects and population bottlenecks followed by an increase in genetic variation if admixture of individuals from multiple native-range sources occurs.

Differential admixture shapes morphological variation among invasive populations of the lizardAnolis sagrei

The biological invasion of the lizard Anolis sagrei provides an opportunity to study evolutionary mechanisms that produce morphological differentiation among non-native populations. Because the A. sagrei invasion represents multiple native-range source populations, differential admixture as well as random genetic drift and natural selection, could shape morphological evolution during the invasion. Mitochondrial DNA (mtDNA) analyses reveal seven distinct native-range source populations for 10 introduced A. sagrei populations from Florida, Louisiana and Texas (USA), and Grand Cayman, with 2-5 native-range sources contributing to each non-native population. These introduced populations differ significantly in frequencies of haplotypes from different native-range sources and in body size, toepad-lamella number, and body shape. Variation among introduced populations for both lamella number and body shape is explained by differential admixture of various source populations; mean morphological values of introduced populations are correlated with the relative genetic contributions from different native-range source populations. The number of source populations contributing to an introduced population correlates with body size, which appears independent of the relative contributions of particular source populations. Thus, differential admixture of various native-range source populations explains morphological differences among introduced A. sagrei populations. Morphological differentiation among populations is compatible with the hypothesis of selective neutrality, although we are unable to test the hypothesis of interdemic selection among introductions from different native-range source populations.