Comparison of tetramethylammonium hydroxide (TMAH), trimethylsulfonium hydroxide (TMSH), and trimethylphenylammonium hydroxide (TMPAH) thermochemolysis for in situ space analysis of organic molecules in planetary environments

One of the main objectives of present and future space exploration missions dedicated to astrobiology is the detection of organic molecules of interest for life (e.g. amino and fatty acids). With this aim, a sample preparation and a gas chromatograph (connected to a mass spectrometer) are generally used. To date, tetramethylammonium hydroxide (TMAH) has been the first and only thermochemolysis reagent to be used for in situ sample preparation and chemical analysis of planetary environments. Although TMAH is widely used in terrestrial laboratories, numerous applications also leverage other thermochemolysis reagents that may be more relevant than TMAH to meet both scientific and technical objectives of space instrumentation. The present study compares the performance of tetramethylammonium hydroxide (TMAH), trimethylsulfonium hydroxide (TMSH), and trimethylphenylammonium hydroxide (TMPAH) reagents on molecules of interest to astrobiology. The study focuses on the analyses of 13 carboxylic acids (C₇-C₃₀), 17 proteinic amino acids, and the 5 nucleobases. Here we report the derivatization yield without stirring or adding solvents, the detection sensitivity with mass spectrometry, and the nature of the degradation products from the reagents produced during pyrolysis. We conclude that TMSH and TMAH are the best reagents for analyzing carboxylic acids and nucleobases. Amino acids are not relevant targets for a thermochemolysis over 300 °C as they are degraded and showed high limits of detection. As TMAH, and probably TMSH, meet the space instrumentation requirements, this study informs sample treatment approaches prior to GC-MS analysis in in situ space studies. The thermochemolysis reaction using TMAH or TMSH is also recommended for space return missions to extract organics from a macromolecular matrix, derivatize polar or refractory organic targets, and volatilize with the fewest organic degradations.

Effects of COVID-19 on Vaccine-Preventable Disease Surveillance Systems in the World Health Organization African Region, 2020

Global emergence of the COVID-19 pandemic in 2020 curtailed vaccine-preventable disease (VPD) surveillance activities, but little is known about which surveillance components were most affected. In May 2021, we surveyed 214 STOP (originally Stop Transmission of Polio) Program consultants to determine how VPD surveillance activities were affected by the COVID-19 pandemic throughout 2020, primarily in low- and middle-income countries, where program consultants are deployed. Our report highlights the responses from 154 (96%) of the 160 consultants deployed to the World Health Organization African Region, which comprises 75% (160/214) of all STOP Program consultants deployed globally in early 2021. Most survey respondents observed that VPD surveillance activities were somewhat or severely affected by the COVID-19 pandemic in 2020. Reprioritization of surveillance staff and changes in health-seeking behaviors were factors commonly perceived to decrease VPD surveillance activities. Our findings suggest the need for strategies to restore VPD surveillance to prepandemic levels.

Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars

The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater's sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbonates along grain boundaries indicate reactions with CO₂-rich water, under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks were stored aboard Perseverance for potential return to Earth.

Feasibility and acceptability of experience sampling among LGBTQ+ young people with self-harmful thoughts and behaviours

This study was the first to determine whether it was feasible and acceptable to use experience sampling methods (ESM) among LGBTQ+ young people, who had current experiences of self-harm. Sixteen LGBTQ+ young people (16-25 years old) took part in the experience sampling study. This included a baseline assessment, a 7-day ESM assessment (participants were sampled six times a day using a phone app), and the option of an interview at the end of the 7-day ESM assessment. Feasibility data was descriptively analysed, with pilot ESM data presented. Qualitative data was thematically analysed to determine the acceptability (barriers and facilitators) of taking part in this study. Study feasibility was assessed by enrolment rate (55.2%), participant retention across assessment period (100%), ESM app feasibility (87.5%), and good adherence to total number of ESM surveys (67.6%). Individual study adherence ranged between 43 and 95.2%. Study acceptability was assessed by participant interviews. Thematic analysis indicated four superordinate themes; (i) Self-reflection and awareness; (ii) Practicalities of ESM surveys; (iii) Daily timeframes; and (iv) Suggestions for future studies. Pilot ESM data demonstrates that there was fluctuation of depressive and anxiety symptoms within- and between- participants over the course of the study, however, greater sample power is needed for full analysis. This study demonstrated that ESM designs are feasible and acceptable among LGBTQ+ young people with current experiences of self-harm. Pilot data indicated that specific experiences and moods are likely to be important to self-harm. These potentially have a temporal influence on self-harm behaviour or ideation, and therefore should be examined in a fully powered sample.

Perseverance rover reveals an ancient delta-lake system and flood deposits at Jezero crater, Mars

[Figure: see text].

Evidence for a Diagenetic Origin of Vera Rubin Ridge, Gale Crater, Mars: Summary and Synthesis of Curiosity's Exploration Campaign

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

Feasibility and acceptability of an intervention for enhancing reintegration in adults with experience of homelessness

BACKGROUND

Service centres for homeless adults are potential settings for implementation of reintegration interventions. This study aimed to evaluate (i) the acceptability of a group-based programme among individuals from the broad population of homeless people and (ii) if a future study of its feasibility and acceptability for re-housed homeless people is warranted.

METHODS

Recruiting participants and intervention facilitators from partnering service centres was thought to improve recruitment and retention, cost-effectiveness and social interactions compared to professional-led interventions. Seven adults with experience of homelessness (three females, four males, mean age 39 years, range 18-63) were recruited to participate in the intervention. The research protocol comprised completion pre/post of scales [Recovering Quality of Life questionnaire; Working Alliance Inventory-short form revised (WAI-SR)] and focus groups, and WAI-SR and focus groups after sessions 3 and 6.

RESULTS

The intervention and research protocols were feasible, with all participants engaging in all sessions, completing all scales and attending all focus groups. The quantitative data demonstrated the feasibility of obtaining practically useful measures of relevant outcomes. In the four focus groups, the intervention received very favourable feedback.

CONCLUSIONS

This study demonstrated initial feasibility and acceptability of an intervention that places minimal burden on infrastructure and promotes user autonomy. This is an important advance as there is increasing recognition that the challenge of reintegration is as much a psychological and social problem as a housing problem. If effective, this style of intervention may serve as a template for future interventions with similar populations.

1201 Performance Evaluation Of A Novel Contactless Breathing Monitor And Machine Learning Algorithm For Sleep Stage Classification In A Healthy Population

Introduction

Although polysomnography (PSG) remains the gold standard for sleep assessment in a lab setting, non-EEG signals such as respiration and motion are directly affected by sleep stages and can be used for sleep stage prediction. Importantly, these signals can be obtained in a low-cost and unobtrusive manner, allowing for large scale and longitudinal data collection in a home environment. The Circadia C100 System (FDA 510(k) clearance expected Q1 2020) is a novel ‘nearable’ device that uses radar for contactless monitoring of respiration and motion. The current study aims to validate the performance of the associated sleep analysis algorithm.

Methods

A total of 41 nights of sleep data were recorded from 33 healthy participants using the device, alongside PSG. Data were recorded both in a sleep lab and home environment. PSG data were scored by RPSGT-certified technicians. Respiration and movement features were extracted, and machine learning algorithms were developed to perform sleep stage classification and predict sleep metrics. Algorithms were trained and validated on PSG data using cross-validation.

Results

An epoch-by-epoch true positive rate of 56.2%, 79.4%, 55.5% and 72.6% was found for ‘Wake’, ‘REM’, ‘Light’ and ‘Deep’ respectively. No statistical differences in performance were found between home-recorded and lab-recorded contactless data. Mean absolute error of total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE) was 13.2 minutes, 11.3 minutes and 3%, respectively. The contactless monitor was found to outperform both medical grade and clinical grade actigraphy based devices: The Philips Actiwatch Spectrum Plus and the Fitbit Alta HR.

Conclusion

Current results are encouraging and suggest that the contactless monitor could be used for long-term sleep assessment and continuous evaluation of sleep therapy outcomes. Further clinical validation work is ongoing in subjects diagnosed with sleep disorders such as obstructive sleep apnea.

Support

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Lessons from a publicly funded tier 2 healthy weight programme in Cornwall, UK

BACKGROUND

The UK has one of the highest prevalence rates of obesity worldwide. Public health departments have a duty to provide some obesity treatment and prevention services. With evidence of effective programmes lacking, we investigate lessons learned from a healthy weight programme in Cornwall, UK.

METHODS

Data from the 12-week multi-component adult healthy weight management programme were obtained for 2012-2016. Descriptive statistics and statistical tests were used to describe participants' demographics, health status and anthropometric measures to explore the enrolment and retention of the programme as well as the impact.

RESULTS

A total of 1872 adults were referred into the programme. Overall, 646 completed the programme and, 48.8% achieved the programme's aim of a >3% reduction in weight. Those who completed and met the programme aim tended to have had healthier outcomes at baseline.

CONCLUSIONS

For those who engage with the programme the impact can be meaningful. However, <1% of the population of Cornwall with overweight or obesity enroled in the programme, and those who benefitted most might have been in least need. Providing services that meet the needs of the population is challenging when a variety of services is needed, and the evidence base is poor.

Gait evaluation in hip osteoarthritic and normal dogs using a serial force plate system

The effect of canine hip osteoarthritis (OA) on vertical force distribution was studied using a serial force platform system. This system allows simultaneous measurement of vertical and horizontal force impulses from each limb of a trotting dog. Using these measurements and novel analysis techniques a complete and precise analysis of load distribution was performed. Load distribution was compared between a group of normal dogs and a group of dogs with radiographic evidence of hip OA. Results of this study indicate that trotting dogs with hip OA redistribute vertical force primarily by shifting force between trotting pairs (side-to-side compensation) rather than within trotting pairs (hind-to-fore compensation).

Force overlap in trotting dogs: a Fourier technique for reconstructing individual limb ground reaction force

Time overlap of ground reaction forces from adjacent footfalls is a pervasive problem in clinical gait analysis. When overlap occurs, splitting the fore- and hindlimb force curves at the minimum point between them underestimates hindlimb impulse and contact time. A better alternative is to reconstruct the force curves that occur in the period of overlap. A Fourier method was used to quantify the shape of hindlimb force curves in Labrador Retrievers and Greyhounds. Fourier coefficients did not differ significantly (p <0.05) between those breeds, indicating that, on average, their shapes are quite similar. The technique reported here uses an empirically determined shape that is, subsequently, scaled to the duration and magnitude of the original hindlimb force curve. A segment of this approximated force curve is then inserted in order to reconstruct the portion of the curve that was obscured by the overlap. Subtracting the reconstructed hindlimb curve, from the original force record, yields a reconstructed forelimb force curve.

Restoration of Acutely Thrombosed Arterio-Venous Fistulae by rTPA and Percutaneous Angioplasty

Acute thrombosis in native arterio-venous fistulae (AVF) results in considerable patient morbidity. Interventional radiology (IR) comprising thrombolysis and percutaneous transluminal angioplasty (PTA) is well established in the management of thrombosed polytetrafluoroethylene (PTFE) grafts. However its role in thrombosed AVF is uncertain. We looked retrospectively at the role of IR in re-establishing blood flow in acutely thrombosed AVF.

Between 1992–2000, 21 episodes of acutely thrombosed AVF in 15 patients (9 females; age range 29–80yrs) were referred for intervention. All fistulae were being used for haemodialysis at the time. Diagnosis was established by angiography and thrombolysis with recombinant tissue plasminogen activator (rTPA) was attempted in all patients. Discrete stenoses when present (n=12) were then treated with PTA and resistant or recurrent stenoses were managed by stent insertion (n=3). Patients were then heparinised for 24 hours.

Technical success as defined by radiological patency was achieved in 86% cases. Clinical success i.e. the ability to reuse of the fistula for haemodialysis was achieved in 62% of the interventions, where patency rates at 3 and 6 months were 92% and 69% respectively. Five patients had recurrence of thrombosis >3 months after the primary procedure, 3 had successful re-intervention. Minor local bleeding was the only complication.

Our retrospective study shows rTPA and PTA is successful in the management of acutely thrombosed AVF. We advocate the routine use of IR as a valuable technique for prolonging the life of native AVF in patients on maintenance haemodialysis.

An ecotoxicological view on neurotoxicity assessment

The numbers of potential neurotoxicants in the environment are raising and pose a great risk for humans and the environment. Currently neurotoxicity assessment is mostly performed to predict and prevent harm to human populations. Despite all the efforts invested in the last years in developing novel in vitro or in silico test systems, in vivo tests with rodents are still the only accepted test for neurotoxicity risk assessment in Europe. Despite an increasing number of reports of species showing altered behaviour, neurotoxicity assessment for species in the environment is not required and therefore mostly not performed. Considering the increasing numbers of environmental contaminants with potential neurotoxic potential, eco-neurotoxicity should be also considered in risk assessment. In order to do so novel test systems are needed that can cope with species differences within ecosystems. In the field, online-biomonitoring systems using behavioural information could be used to detect neurotoxic effects and effect-directed analyses could be applied to identify the neurotoxicants causing the effect. Additionally, toxic pressure calculations in combination with mixture modelling could use environmental chemical monitoring data to predict adverse effects and prioritize pollutants for laboratory testing. Cheminformatics based on computational toxicological data from in vitro and in vivo studies could help to identify potential neurotoxicants. An array of in vitro assays covering different modes of action could be applied to screen compounds for neurotoxicity. The selection of in vitro assays could be guided by AOPs relevant for eco-neurotoxicity. In order to be able to perform risk assessment for eco-neurotoxicity, methods need to focus on the most sensitive species in an ecosystem. A test battery using species from different trophic levels might be the best approach. To implement eco-neurotoxicity assessment into European risk assessment, cheminformatics and in vitro screening tests could be used as first approach to identify eco-neurotoxic pollutants. In a second step, a small species test battery could be applied to assess the risks of ecosystems.

An automated curation procedure for addressing chemical errors and inconsistencies in public datasets used in QSAR modelling

The increasing availability of large collections of chemical structures and associated experimental data provides an opportunity to build robust QSAR models for applications in different fields. One common concern is the quality of both the chemical structure information and associated experimental data. Here we describe the development of an automated KNIME workflow to curate and correct errors in the structure and identity of chemicals using the publicly available PHYSPROP physicochemical properties and environmental fate datasets. The workflow first assembles structure-identity pairs using up to four provided chemical identifiers, including chemical name, CASRNs, SMILES, and MolBlock. Problems detected included errors and mismatches in chemical structure formats, identifiers and various structure validation issues, including hypervalency and stereochemistry descriptions. Subsequently, a machine learning procedure was applied to evaluate the impact of this curation process. The performance of QSAR models built on only the highest-quality subset of the original dataset was compared with the larger curated and corrected dataset. The latter showed statistically improved predictive performance. The final workflow was used to curate the full list of PHYSPROP datasets, and is being made publicly available for further usage and integration by the scientific community.

Inner-Centeredness of Highly Creative Adolescents

The Torrance Tests of Creative Thinking were administered to 1,000 metropolitan sixth-graders from whom 4% were selected as being “highly creative.” Miller's tests for locus of control and of evaluation were also given to this latter group and to a control group. Significant differences on the locus of evaluation measure were found between the “high creatives” and a control group, but the differences between the groups were not significant on the measure of locus of control. Although the predicted relationship between creativity and an internal locus of evaluation appeared to be supported, the extent to which the original tests had been successful in selecting people with creative ability was questioned.

HIV research trials versus standard clinics for antiretroviral-naïve patients: the outcomes differ but do the patients?

Exclusion criteria for HIV treatment-naïve drug trials can be stringent and selection bias exists, making it difficult to extrapolate results into the 'real world' clinical situation. We aim to compare the demographics, virological outcomes and psychosocial complexity in adult HIV-infected treatment-naïve patients from our cohort initiating combination antiretroviral therapy (cART) in research trials versus standard clinics. In our unit from 2006 to 2011, 1202 standard clinic and 69 research trial patients initiated cART; every eighth standard clinics patient was included to create a standard clinics:research trials patient ratio of 2:1. Notes were retrospectively reviewed for patient demographics, attendance rates and virological outcomes. Data from 221 antiretroviral-naïve patients starting cART were analysed: 152 standard clinic patients and 69 from research trials. In the research trials group, there was an overrepresentation of men (p = 0.041), men who have sex with men (p < 0.001), patients of white ethnicity (p = 0.01), employed patients (p = 0.01) and patients using excessive alcohol (p = 0.02). There was equal representation of drug use, depression and referral to psychology, psychiatry and social work in both groups. The research trials group at baseline had significantly higher CD4 counts (p < 0.001), lower viral loads (p = 0.01) and more patients achieved undetectable viral loads at three (p < 0.001), six (p < 0.001) and 24 months (p = 0.033). There is a prevailing common preconception that participants in clinical trials are uncomplicated, unlike their 'real-life' counterparts. We demonstrated important similarities in psychosocial complexity as well as differences in demographics and virological outcomes in trial and non-trial patients. Clinicians need to be aware of these discrepancies to ensure the facilitation of a heterogeneous population participating in research trials.

Molecular cloning, characterisation and mRNA expression of the ryanodine receptor from the peach-potato aphid, Myzus persicae

The peach potato aphid, Myzus persicae, is one of the most important agricultural pests of temperate climates. It is mainly controlled through the judicious application of insecticides; however, over time, aphids have developed resistance to many insecticidal classes. The recent introduction of synthetic diamide insecticides, with a novel mode of action, potentially offers new tools to control aphid populations. These diamides act on the ryanodine receptor (RyR), a large endoplasmic calcium release channel. In this study we have cloned cDNAs encoding the complete open reading frame of the RyR from M. persicae. The open reading frame is 15,306 base pairs long and encodes a protein of 5101 amino acids. The aphid RyR shares many of the features of other insect and vertebrate RyRs, including a highly conserved transmembrane region. However, unlike the other RyRs characterised to date, the M. persicae channel does not display alternative splicing at any stage of its developmental cycle, so it cannot generate functional variants of the channel.

Spatial variation in the effects of size and age on reproductive dynamics of common coral trout Plectropomus leopardus

The effects of size and age on reproductive dynamics of common coral trout Plectropomus leopardus populations were compared between coral reefs open or closed (no-take marine reserves) to fishing and among four geographic regions of the Great Barrier Reef (GBR), Australia. The specific reproductive metrics investigated were the sex ratio, the proportion of vitellogenic females and the spawning fraction of local populations. Sex ratios became increasingly male biased with length and age, as expected for a protogyne, but were more male biased in southern regions of the GBR (Mackay and Storm Cay) than in northern regions (Lizard Island and Townsville) across all lengths and ages. The proportion of vitellogenic females also increased with length and age. Female P. leopardus were capable of daily spawning during the spawning season, but on average spawned every 4·3 days. Mature females spawned most frequently on Townsville reserve reefs (every 2·3 days) and Lizard Island fished reefs (every 3·2 days). Females on Mackay reefs open to fishing showed no evidence of spawning over 4 years of sampling, while females on reserve reefs spawned only once every 2-3 months. No effect of length on spawning frequency was detected. Spawning frequency increased with age on Lizard Island fished reefs, declined with age on Storm Cay fished reefs, and declined with age on reserve reefs in all regions. It is hypothesized that the variation in P. leopardus sex ratios and spawning frequency among GBR regions is primarily driven by water temperature, while no-take management zones influence spawning frequency depending on the region in which the reserve is located. Male bias and lack of spawning activity on southern GBR, where densities of adult P. leopardus are highest, suggest that recruits may be supplied from central or northern GBR. Significant regional variation in reproductive traits suggests that a regional approach to management of P. leopardus is appropriate and highlights the need for considering spatial variation in reproduction where reserves are used as fishery or conservation management tools.

Multiple independent emergences of type 2 vaccine-derived polioviruses during a large outbreak in northern Nigeria

Since 2005, a large poliomyelitis outbreak associated with type 2 circulating vaccine-derived poliovirus (cVDPV2) has occurred in northern Nigeria, where immunization coverage with trivalent oral poliovirus vaccine (tOPV) has been low. Phylogenetic analysis of P1/capsid region sequences of isolates from each of the 403 cases reported in 2005 to 2011 resolved the outbreak into 23 independent type 2 vaccine-derived poliovirus (VDPV2) emergences, at least 7 of which established circulating lineage groups. Virus from one emergence (lineage group 2005-8; 361 isolates) was estimated to have circulated for over 6 years. The population of the major cVDPV2 lineage group expanded rapidly in early 2009, fell sharply after two tOPV rounds in mid-2009, and gradually expanded again through 2011. The two major determinants of attenuation of the Sabin 2 oral poliovirus vaccine strain (A481 in the 5'-untranslated region [5'-UTR] and VP1-Ile143) had been replaced in all VDPV2 isolates; most A481 5'-UTR replacements occurred by recombination with other enteroviruses. cVDPV2 isolates representing different lineage groups had biological properties indistinguishable from those of wild polioviruses, including efficient growth in neuron-derived HEK293 cells, the capacity to cause paralytic disease in both humans and PVR-Tg21 transgenic mice, loss of the temperature-sensitive phenotype, and the capacity for sustained person-to-person transmission. We estimate from the poliomyelitis case count and the paralytic case-to-infection ratio for type 2 wild poliovirus infections that ∼700,000 cVDPV2 infections have occurred during the outbreak. The detection of multiple concurrent cVDPV2 outbreaks in northern Nigeria highlights the risks of cVDPV emergence accompanying tOPV use at low rates of coverage in developing countries.

Age estimation and validation for South Pacific albacore Thunnus alalunga

Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.

Comparative biology of tropical Lethrinus species (Lethrinidae): challenges for multi-species management

Life-history characteristics of six tropical Lethrinus species sampled from the Great Barrier Reef World Heritage Area were compared. Two species groups were identified based on fork length (LF ): large species with maximum LF > 640 mm (longface emperor Lethrinus olivaceus, yellowlip emperor Lethrinus xanthochilus and spangled emperor Lethrinus nebulosus) and small species with maximum LF < 480 mm (Pacific yellowtail emperor Lethrinus atkinsoni, pink ear emperor Lethrinus lentjan and ornate emperor Lethrinus ornatus). Lifespan was not correlated with LF . Early growth for all species was rapid and similar during the first few years of life, but coefficients of the von Bertalanffy growth function varied considerably among species. Growth also differed between sexes for L. atkinsoni. Reproductive characteristics varied among species, with peak periods of spawning occurring in November to December for L. atkinsoni, July to August for L. nebulous, September to October for L. olivaceus and a protracted season for L. lentjan, although fewer samples were available for the last two species. Sex-specific LF and age distributions and gonad histology of L. lentjan were suggestive of a functional protogynous reproductive pattern, as observed in other lethrinids. Gonad histology indicated non-functional protogynous hermaphroditism for L. atkinsoni and L. nebulosus. The diversity of life histories among these closely related species emphasizes the difficulty in devising single management strategies appropriate for multi-species fisheries and illustrates the importance of understanding species-specific life histories to infer responses to exploitation.

Ultra-low exposure to α-7 nicotinic acetylcholine receptor partial agonists elicits an improvement in cognition that corresponds with an increase in α-7 receptor expression in rodents: implications for low dose clinical efficacy

Αlpha-7 neuronal nicotinic receptors (NNRs) are considered targets for cognitive enhancement in schizophrenia and Alzheimer's disease. AZD0328 is an alpha-7 NNR partial agonist that enhances cognition in rodents and nonhuman primates at sub-microgram to microgram doses. We hypothesized that increased expression of the alpha-7 receptor contributes to this beneficial activity at low doses and tested this by examining the effect of AZD0328 using in vivo and ex vivo binding, RT-PCR and cognitive function in rodents. AZD0328 (0.00178 mg/kg) was subcutaneously administered to mice 4, 24, 48 and 72 hours prior to testing in novel object recognition and produced a significant increase in cognition at 4, 24 and 48 h post-dosing. In vivo binding was examined in rat brain using [(3)H]AZ11637326 and there was a dose-dependent reduction in receptor binding at higher doses of AZD0328 (0.001-3 mg/kg), and a second alpha-7 partial agonist, SSR180711 (0.01-30 mg/kg). Lower doses of both compounds (0.0001 mg/kg) produced a significant increase in binding of [(3)H]AZ11637326. Ex vivo binding using [(125)I]-α-bungarotoxin, showed a significant increase in receptor number (B(max.)) in the frontal cortex or hippocampus with no significant effect on receptor affinity (K(d)) 2 h post administration of AZD0328. [(3)H]AZ11637326 administered 1.5 h following AZD0328 produced a significant increase in specific binding in rat brain regions. We found that the effect on receptor number was long-lasting, with [(125)I]-α-bungarotoxin binding increased in rats given AZD0328 for 2-48 h, but this was not accompanied by increased mRNA synthesis. SSR180711 produced a similar increase in B(max.) and specific binding with no effect on K(d). Therefore, trace dose of alpha-7 partial agonists has rapid onset and produces a profound, sustained effect on novel object recognition in mice that corresponds by dose to an increase in receptor number in rat brain. These findings provide an explanation for the acute and sustained benefit of alpha-7 receptor activation in working memory in nonhuman primates and guidance for drug development initiatives and treatment regimens for nicotinic partial agonists.

Outbreak of type 2 vaccine-derived poliovirus in Nigeria: emergence and widespread circulation in an underimmunized population

Wild poliovirus has remained endemic in northern Nigeria because of low coverage achieved in the routine immunization program and in supplementary immunization activities (SIAs). An outbreak of infection involving 315 cases of type 2 circulating vaccine-derived poliovirus (cVDPV2; >1% divergent from Sabin 2) occurred during July 2005-June 2010, a period when 23 of 34 SIAs used monovalent or bivalent oral poliovirus vaccine (OPV) lacking Sabin 2. In addition, 21 "pre-VDPV2" (0.5%-1.0% divergent) cases occurred during this period. Both cVDPV and pre-VDPV cases were clinically indistinguishable from cases due to wild poliovirus. The monthly incidence of cases increased sharply in early 2009, as more children aged without trivalent OPV SIAs. Cumulative state incidence of pre-VDPV2/cVDPV2 was correlated with low childhood immunization against poliovirus type 2 assessed by various means. Strengthened routine immunization programs in countries with suboptimal coverage and balanced use of OPV formulations in SIAs are necessary to minimize risks of VDPV emergence and circulation.

Practical guidelines for routine intensity-modulated radiotherapy verification: pre-treatment verification with portal dosimetry and treatment verification with in vivo dosimetry

The purpose of this work is to provide guidelines for the routine use of portal dosimetry and in vivo diode measurements to verify intensity-modulated radiotherapy (IMRT) treatments. To achieve tolerance levels that are sensitive enough to intercept problems, both the portal dosimetry and the in vivo procedure must be optimised. Portal dosimetry was improved by the introduction of an optimised two-dimensional (2D) profile correction, which also accounted for the effect of backscatter from the R-arm. The scaled score, indicating the fraction of points not meeting the desired gamma evaluation criteria within the field opening, was determined as the parameter of interest. Using gamma criteria of a 3% dose difference and 3 mm distance to agreement, a "scaled score" threshold value of 1.5% was chosen to indicate excessive tongue and groove and other problems. The pre-treatment portal dosimetry quality assurance (QA) does not encompass verification of the patient dose calculation or position, and so it is complemented by in vivo diode measurements. Diode positioning is crucial in IMRT, and so we describe a method for diode positioning at any suitable point. We achieved 95% of IMRT field measurements within ±5% and 99% within ±8%, with improved accuracy being achieved over time owing to better positioning. Although the careful preparation and setup of the diode measurements can be time-consuming, this is compensated for by the time efficiency of the optimised procedure. Both methods are now easily absorbed into the routine work of the department.

Test of recrudescence hypothesis for overwintering of West Nile virus in gray catbirds

West Nile virus is a pathogen of concern for both human and wildlife health. Although many aspects of the ecology of West Nile virus are well understood, the mechanisms by which this and similar mosquito-borne viruses overwinter and become reinitiated each spring in temperate regions is not known. A thorough understanding of this mechanism is crucial to risk assessment and development of control strategies. One of the hypotheses to explain the mechanism by which this virus persists from year to year is the spring recrudescence of latent virus in avian reservoir hosts. Stress-related immunosuppression is implicated in the recrudescence of latent viruses in birds. We tested the spring recrudescence hypothesis in a controlled laboratory experiment using hatching-year gray catbirds (Dumatella carolinensis) captured in northern Ohio (July-August 2006). Catbirds (n = 60) were experimentally infected (September 2006) and later examined for the effects of immunosuppression through exogenous hormones and artificially induced migratory disposition. We found no effect of either testosterone or migratory behavior on infection status in any of the treatment birds. Moreover, we detected no viral RNA in the kidney, spleen, brain, or liver upon necropsy at 24 wk postinfection.

Effect of informational internet web pages on patients' decision-making: randomised controlled trial regarding choice of spinal or general anaesthesia for orthopaedic surgery

This study explored whether patients' preference for particular types of anaesthesia could be influenced pre-operatively by giving them the addresses of various relevant websites. Patients at an orthopaedic pre-assessment education clinic completed a questionnaire, which included a short multiple-choice general knowledge quiz about anaesthesia, and also questioned them as to their choice of anaesthesia (general or neuraxial). Patients were randomly assigned to intervention or control groups. Intervention group members were given the addresses of three relevant anaesthesia and health related websites to access at home. All patients were asked to complete the questionnaires on a second occasion, before surgery. Initially, most patients stated a preference for general anaesthesia. Subsequently, the intervention group altered their preference towards neuraxial anaesthesia compared to the control group (p < or = 0.0001). The increase in median (IQR [range]) anaesthesia knowledge test score was greater in the intervention group (from 10.0 (9.0-12.0 [5.0-14.0]) to 13.0 (11.0-14.0 [6.0-14.0])) than in the control group (from 10.0 (9.0-11.5 [3.0-13.0]) to 11.0 (9.0-12.0 [4.0-14.0]); p = 0.0068).

The size of the spleen by magnetic resonance imaging in patients with cystic fibrosis; with and without diabetes--a novel observational study

BACKGROUND

Magnetic resonance imaging (MRI) has been shown to be a useful tool to evaluate the volume of the pancreas. There is currently no information about the size of the spleen in cystic fibrosis (CF) patients.

PATIENTS AND METHODS

We investigated 51 adult volunteers: 28 pancreatic insufficient CF patients [13 with CF-related diabetes (CFRD) and 15 non-diabetic] and 23 male non-CF patients [12 with type 1 diabetes mellitus (T1DM) and 11 healthy control subjects]. Patients with known liver cirrhosis or portal hypertension were excluded. The size of the spleen was measured in all subjects by an investigator unaware of patients' clinical status. For comparison of spleen size in the four study groups only male CF patients were included. For CF patients, spleen size was compared with forced expiratory volume in 1 s (FEV(1)), body mass index (BMI), total number of days of intravenous (IV) antibiotic treatment for pulmonary exacerbations in year previous to study, levels of circulating white blood cells, glycosylated haemoglobin A1c (HbA1c), and exocrine function of the pancreas, as assessed by daily requirement of oral lipase.

RESULTS

Amongst the four study groups, spleen size was greatest in the male non-diabetic CF patients (P = 0.01). For CF patients, spleen size was greater in male compared to female patients (P = 0.012). For patients with CFRD, there was an inverse correlation between the spleen size and HbA1c (r = -0.59, P = 0.04) and the daily intake of supplementary lipase (r = -0.63, P = 0.02). The size of the spleen in patients with CFRD, but not in CF patients without CFRD, inversely correlated with the days of IV antibiotic treatment received in the year previous to the study (r = -0.67, P = 0.012). There was no correlation between spleen size and BMI, FEV1 and white blood cell counts in any group.

CONCLUSION

On MRI, the spleen size was greatest in male non-diabetic CF patients in comparison with other groups. The size of the spleen in CFRD patients was smaller when diabetes was poorly controlled, when exocrine pancreatic function was greatly impaired and in those with greater need for IV antibiotics in the year prior to the study.

Superconductivity in CuxBi2Se3 and its implications for pairing in the undoped topological insulator

Bi2Se3 is one of a handful of known topological insulators. Here we show that copper intercalation in the van der Waals gaps between the Bi2Se3 layers, yielding an electron concentration of approximately 2x10{20} cm{-3}, results in superconductivity at 3.8 K in CuxBi2Se3 for 0.12<or=x<or=0.15. This demonstrates that Cooper pairing is possible in Bi2Se3 at accessible temperatures, with implications for studying the physics of topological insulators and potential devices.

Increased accuracy of batch fecundity estimates using oocyte stage ratios in Plectropomus leopardus

Using the ratio of the number of migratory nuclei to hydrated oocytes to estimate batch fecundity of common coral trout Plectropomus leopardus increases the time over which samples can be collected and, therefore, increases the sample size available and reduces biases in batch fecundity estimates.

Tetragonal-to-orthorhombic structural phase transition at 90 K in the superconductor Fe(1.01)Se

In this Letter we show that superconducting Fe(1.01)Se undergoes a structural transition at 90 K from a tetragonal to an orthorhombic phase but that nonsuperconducting Fe(1.03)Se does not. High resolution electron microscopy at low temperatures further reveals an unexpected additional modulation of the crystal structure of the superconducting phase that involves displacements of the Fe atoms, and that the nonsuperconducting composition shows a different, complex nanometer-scale structural modulation. Finally, we show that magnetism is not the driving force for the phase transition in the superconducting phase.

The metal-insulator transition in Fe(1.01-x)Cu(x)Se

Iron selenide, Fe(1.01)Se, the layered parent compound of the recently discovered superconducting arsenide family, has previously been shown to be non-magnetic and superconducting with a critical temperature of 8 K. Here we show that copper can be substituted at the iron site in Fe(1.01)Se up to a solubility limit of 20-30%, after which a first-order transition to the three-dimensional CuFeSe(2) structure type is observed. As little as 1.5% copper is sufficient to suppress the superconductivity, and 4% drives the system through a metal-insulator transition. A local magnetic moment is introduced, which maximizes near 12% doping, where a spin-glass transition near 15 K is observed.

Physiological consequences of the P2328S mutation in the ryanodine receptor (RyR2) gene in genetically modified murine hearts

Aim

To explore the physiological consequences of the ryanodine receptor (RyR2)-P2328S mutation associated with catecholaminergic polymorphic ventricular tachycardia (CPVT).

Methods

We generated heterozygotic (RyR2^p/s) and homozygotic (RyR2^s/s) transgenic mice and studied Ca²⁺ signals from regularly stimulated, Fluo-3-loaded, cardiac myocytes. Results were compared with monophasic action potentials (MAPs) in Langendorff-perfused hearts under both regular and programmed electrical stimulation (PES).

Results

Evoked Ca²⁺ transients from wild-type (WT), heterozygote (RyR2^p/s) and homozygote (RyR2^s/s) myocytes had indistinguishable peak amplitudes with RyR2^s/s showing subsidiary events. Adding 100 nm isoproterenol produced both ectopic peaks and subsidiary events in WT but not RyR2^p/s and ectopic peaks and reduced amplitudes of evoked peaks in RyR2^s/s. Regularly stimulated WT, RyR2^p/s and RyR2^s/s hearts showed indistinguishable MAP durations and refractory periods. RyR2^p/s hearts showed non-sustained ventricular tachycardias (nsVTs) only with PES. Both nsVTs and sustained VTs (sVTs) occurred with regular stimuli and PES with isoproterenol treatment. RyR2^s/s hearts showed higher incidences of nsVTs before but mainly sVTs after introduction of isoproterenol with both regular stimuli and PES, particularly at higher pacing frequencies. Additionally, intrinsically beating RyR2^s/s showed extrasystolic events often followed by spontaneous sVT.

Conclusion

The RyR2-P2328S mutation results in marked alterations in cellular Ca²⁺ homeostasis and arrhythmogenic properties resembling CPVT with greater effects in the homozygote than the heterozygote demonstrating an important gene dosage effect.

Applying computer-assisted structure elucidation algorithms for the purpose of structure validation: revisiting the NMR assignments of hexacyclinol

Computer-assisted structure elucidation (CASE) using a combination of 1D and 2D NMR data has been available for a number of years. These algorithms can be considered as "logic machines" capable of deriving all plausible structures from a set of structural constraints or "axioms", defined by the spectroscopic data and associated chemical information or prior knowledge. CASE programs allow the spectroscopist not only to determine structures from spectroscopic data but also to study the dependence of the proposed structure on changes to the set of axioms. In this article, we describe the application of the ACD/Structure Elucidator expert system to help resolve the conflict between two different hypothetical hexacyclinol structures derived by different researchers from the NMR spectra of this complex natural product. It has been shown that the combination of algorithms for both structure elucidation and structure validation delivered by the expert system enables the identification of the most probable structure as well as the associated chemical shift assignments.

Performance validation of neural network based (13)c NMR prediction using a publicly available data source

The validation of the performance of a neural network based 13C NMR prediction algorithm using a test set available from an open source publicly available database, NMRShiftDB, is described. The validation was performed using a version of the database containing ca. 214,000 chemical shifts as well as for two subsets of the database to compare performance when overlap with the training set is taken into account. The first subset contained ca. 93,000 chemical shifts that were absent from the ACD\CNMR DB, the "excluded shift set" used for training of the neural network and the ACD\CNMR prediction algorithm, while the second contained ca. 121,000 shifts that were present in the ACD\CNMR DB training set, the "included shift set". This work has shown that the mean error between experimental and predicted shifts for the entire database is 1.59 ppm, while the mean deviation for the subset with included shifts is 1.47 and 1.74 ppm for excluded shifts. Since similar work has been reported online for another algorithm we compared the results with the errors determined using Robien's CNMR Neural Network Predictor using the entire NMRShiftDB for program validation.

Field investigation of perinatal mortality in friesian cattle associated with myocardial degeneration and necrosis

Perinatal mortality and stillbirths were investigated in an extensively managed herd of Friesian cows and heifers calving over a 2-year period: 504 cows were calved and 215 heifers. Cows were bred to Friesian and Jersey bulls using natural service. The perinatal fetal mortality rate was 7.5% for cows and 30% for heifers. An experienced stockman managed these calvings and veterinary assistance was required only on nine occasions. All stillborn fetuses were examined post-mortem by the Veterinary Laboratories Agency, Carmarthen and no infectious agent was identified on any occasion. Thyroid hyperplasia was found in two fetuses. In blood samples taken from 10 late pregnant heifers, mean glutathione peroxidase values were 7.9 +/- 1.7 IU/ml Packed Cell Volume (PCV). Tissues from eight fetuses were submitted to the University of Liverpool for histopathological examination; all presented lesions consistent with myocardial degeneration and necrosis of the left ventricle. Following treatment of 205 late pregnant heifers with sodium selenite and vitamin E, the overall perinatal mortality rate in these cattle fell to below 11%.