925 research outputs found

    Effect of a trace element addition strategy on volatile fatty acid accumulation in thermophilic anaerobic digestion of food waste

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    PurposeA trace element (TE) supplementation strategy previously shown to be effective in mesophilic conditions was tested for thermophilic digestion of source segregated domestic food waste.MethodsInoculum from a mesophilic anaerobic digester treating municipal wastewater biosolids was successfully acclimated to thermophilic temperature (55 °C) with food waste as a substrate. Four laboratory-scale digesters were maintained at a loading of 2 g VS l?1 day?1 with one pair receiving TE supplementation. Two more pairs of digesters were incrementally loaded to 3 and 4 g VS l?1 day?1, respectively, and also received TE.ResultsAll digesters performed well for the first 3–4 months of operation, but volatile fatty acid (VFA) concentrations in those without TE showed no recovery from an initial small accumulation. On continued operation, VFA concentrations increased in all digesters, especially those at higher loading rates or without TE supplementation, reaching &gt;30 g l?1. Under these meta-stable conditions, a deliberate disturbance to daily feeding (cessation then resumption) led to acetic acid accumulation, a fall in pH and a sharp increase in the ratio of partial to intermediate alkalinity. Increases in VFA corresponded to an increasing total ammonia nitrogen concentration which appeared to become inhibitory at ~2,500 mg N l?1.ConclusionsWhile TE supplementation delayed the onset and reduced the rate of VFA accumulation, it was unable to sustain stable digestion of this substrate in thermophilic conditions.<br/

    State-to-State Rotational Rate Constants for CO+He: Infrared Double Resonance Measurements and Simulation of the Data Using the SAPT Theoretical Potential Energy Surface

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    An extensive data set of 54 time-resolved pump-probe measurements was used to examine CO+He rotational energy transfer within the CO v=2 rotational manifold. Rotational levels in the range Ji=2-9 were excited and collisional energy transfer of population to the levels Jf=1-10 was monitored. The resulting data set was analyzed by fitting to numerical solutions of the master equation. State-to-state rate constant matrices were generated using fitting law functions and ab initio theoretical calculations that employed the SAPT potential energy surface of Heijmen et al. [J. Chem. Phys. 107, 9921 (1997)]. Fitting laws based on the modified exponential gap (MEG), statistical power exponential gap (SPEG), and energy corrected sudden with exponential power (ECS-EP) models all yielded acceptable simulations of the kinetic data, as did the theoretical rate constants. However, the latter were unique in their ability to reproduce both our kinetic data and the pressure broadening coefficients for CO+He. These results provide an impressive demonstration of the quality of the symmetry adapted perturbation theory (SAPT) potential energy surface

    Eligibility screening older research participants using remote cognitive assessment—experiences and reflections from a primary care randomised controlled trial

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    Background The COVID-19 pandemic forced many research teams to adjust the way they conduct studies, including moving to remote delivery of some or all of their recruitment and data collection processes. The Montreal Cognitive Assessment (MoCA) is widely used in research and is available in multiple formats for different groups and assessment settings. Here, we reflect on our experiences of administering the MoCA Blind/Telephone as part of the initial telephone eligibility check for participation in a randomised controlled trial with community-dwelling older people with frailty. Main body In response to COVID-19, a number of changes were made to the trial’s screening and recruitment procedures, to minimise the amount of time the researchers would spend in the participants’ homes when recruitment began in May 2021. One of the changes was for the researchers to conduct a cognitive assessment for eligibility during an initial telephone call, rather than during the subsequent home visit for consent and baseline data collection. We found that in comparison with conducting the assessment in-person, telephone administration caused uncertainty for the researchers about whether participants were struggling to answer questions due to cognition or hearing impairment. Some participants experienced practical difficulties when combining holding a telephone and completing one of the assessment items. It was hard for the researchers to judge the emotional impact that undertaking the assessment was having on the older people on the telephone, without visual warning signs of fatigue or mood. We discuss the potential impact of these issues on trial recruitment and participant engagement, and the feasibility of videoconferencing as an alternative method of conducting the MoCA. Conclusion The MoCA is a useful tool when cognitive impairment is part of screening and data collection and it is helpful to have the option to use the test remotely. However, as we have found, telephone testing is not always straightforward. Researchers should weigh up the pros and cons for each individual study, especially those involving older adults. If choosing remote methods, consider the practicality of using videoconferencing and think about the possible impact of telephone assessment on the relationship with the (potential) research participants. Trial registration Personalised care planning for older people with frailty ISRCTN16123291 28/08/2020

    IONIZATION MEASUREMENT AND SPECTROSCOPY OF ThS AND ThS+^+

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    Author Institution: Department of Chemistry, Emory University, Atlanta; Ga 30322Gas-phase thorium sulfide has been produced via laser ablation of thorium in a jet-cooled expansion of 0.1\% H2_2S/He carrier gas. Electronic spectra have been recorded for the first time by laser-induced fluorescence (LIF) over the region 17500-23650 cm−1^{-1}. Resonance-enhanced multiphoton ionization (REMPI) was used in conjunction with a Wiley-McLaren time-of-flight mass spectrometer to confirm LIF assigments of seven rotationally-resolved bands belonging to ThS. Dispersing fluorescence from the \italic{[22.13]}1^1Π\Pi-\italic{X}1^1ÎŁ\Sigmag_g transition revealed a vibrational progression of the ground electronic state of ThS, for which the vibrational constants were ω\omegae_e = 520.0(7) cm−1^{-1} and ω\omegae_eχ\chie_e = 11.0(9) cm−1^{-1}. An accurate value for the ionization potential of ThS as well as term energies of ThS+^+ up to v+^+ = 7 in the 2^2ÎŁ\Sigma+^+ ground state and v+^+ = 3 in the 2^2Δ\Delta3/2_{3/2} first excited state have been obtained using two-photon pulsed-field ionization zero kinetic energy photoelectron spectroscopy (PFI-ZEKE). Vibrational constants for these states have also been detemined. High-level electronic structure calculations performed for ThS and ThS+^+ gave term energies and molecular parameters that are in excellent agreement with the experimental results. The change in bond characteristics upon ionization of ThS is found to be consistent with that observed for HfO, HfS, and ThO

    Estimating the incidence, prevalence and true cost of asthma in the UK: secondary analysis of national stand-alone and linked databases in England, Northern Ireland, Scotland and Wales-a study protocol.

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    INTRODUCTION: Asthma is now one of the most common long-term conditions in the UK. It is therefore important to develop a comprehensive appreciation of the healthcare and societal costs in order to inform decisions on care provision and planning. We plan to build on our earlier estimates of national prevalence and costs from asthma by filling the data gaps previously identified in relation to healthcare and broadening the field of enquiry to include societal costs. This work will provide the first UK-wide estimates of the costs of asthma. In the context of asthma for the UK and its member countries (ie, England, Northern Ireland, Scotland and Wales), we seek to: (1) produce a detailed overview of estimates of incidence, prevalence and healthcare utilisation; (2) estimate health and societal costs; (3) identify any remaining information gaps and explore the feasibility of filling these and (4) provide insights into future research that has the potential to inform changes in policy leading to the provision of more cost-effective care. METHODS AND ANALYSIS: Secondary analyses of data from national health surveys, primary care, prescribing, emergency care, hospital, mortality and administrative data sources will be undertaken to estimate prevalence, healthcare utilisation and outcomes from asthma. Data linkages and economic modelling will be undertaken in an attempt to populate data gaps and estimate costs. Separate prevalence and cost estimates will be calculated for each of the UK-member countries and these will then be aggregated to generate UK-wide estimates. ETHICS AND DISSEMINATION: Approvals have been obtained from the NHS Scotland Information Services Division's Privacy Advisory Committee, the Secure Anonymised Information Linkage Collaboration Review System, the NHS South-East Scotland Research Ethics Service and The University of Edinburgh's Centre for Population Health Sciences Research Ethics Committee. We will produce a report for Asthma-UK, submit papers to peer-reviewed journals and construct an interactive map

    Supporting well-being in retirement through meaningful social roles: Systematic review of intervention studies

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    Context The marked demographic change toward greater proportions of older people in developed nations poses significant challenges for health and social care. Several studies have demonstrated an association between social roles in later life and positive health and well-being outcomes. After retiring from work, people may lose roles that provide purpose and social contacts. The outcomes of interventions to promote social roles in retirement have not been systematically reviewed. Methods We examined three research questions: (1) What kinds of intervention have been developed to promote social roles in retirement? (2) How much have they improved perceived roles? (3) Have these roles improved health or well-being? We included those studies that evaluated the provision of social roles; used a control or comparison group; targeted healthy retirement-transition adults who were living in the community; provided an abstract written in English; took place in a highly developed nation; and reported social role, health, or well-being outcomes. We searched eight electronic databases and combined the results with hand searches. Findings Through our searches, we identified 9,062 unique publications and eleven evaluative studies of acceptable quality, which reported seven interventions that met our inclusion criteria. These interventions varied in year of inception and scope, but only two were based outside North America. The studies rarely reported the quality or meaning of roles. Only three studies used random allocation, thus limiting inferences of causality from these studies. Interventions providing explicit roles and using supportive group structures were somewhat effective in improving one or more of the following: life satisfaction, social support and activity, physical health and activity, functional health, and cognition. Conclusions Social role interventions may improve health and well-being for people in retirement transition. Future research should improve the quality of intervention and assessment and look at which interventions are most effective and acceptable in facilitating social roles for diverse older populations. © 2013 Milbank Memorial Fund

    The cost of community research—recruiting community-dwelling participants to a feasibility primary care cluster randomised controlled trial

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    Background To support a robust evidence base for the organisation and provision of community-delivered health services for older people, clinical trials need to be designed to account for community-based participant recruitment. There is currently little reported information available on the time and cost of recruiting community-dwelling older people, which makes the completion of cost attribution documentation problematic when applying for research funding. Main body We aimed to establish the amount of researcher time it takes to recruit community-dwelling older people to a feasibility primary care cluster randomised controlled trial, including collecting baseline data. The trial was part of a programme of work investigating an intervention to improve the quality of life for older people with frailty. Two researchers conducting home visits to recruit and collect baseline data from participants recorded the time spent on travelling to and from the visit, at the visit itself and any associated administration. The median total researcher activity time per visit was 148 min. We discuss the various elements of recruitment and data collection activity and the factors that impacted the length of time taken, including location, individuals’ capacity and cognition, hearing and visual impairment and the desire for social contact. Conclusion Studies cannot reach their recruitment targets if they are unrealistically planned and resourced. We recommend that trials recruiting older people in the community allocate two and a half hours of researcher time per person, on average, for consent, baseline data collection, travel and administration. We acknowledge that a variety of different factors will mean that researcher activity will vary between different community-based trials. Our findings give a good starting point for timing calculations, and evidence on which to base the justification of research activity costings. Trial registration Personalised care planning for older people with frailty ISRCTN12363970. 08/11/2018

    Dipole-phonon quantum logic with alkaline-earth monoxide and monosulfide cations

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    Dipole-phonon quantum logic (DPQL) leverages the interaction between polar molecular ions and the motional modes of a trapped-ion Coulomb crystal to provide a potentially scalable route to quantum information science. Here, we study a class of candidate molecular ions for DPQL, the cationic alkaline-earth monoxides and monosulfides, which possess suitable structure for DPQL and can be produced in existing atomic ion experiments with little additional complexity. We present calculations of DPQL operations for one of these molecules, CaO+^+, and discuss progress towards experimental realization. We also further develop the theory of DPQL to include state preparation and measurement and entanglement of multiple molecular ions.Comment: 10 pages, 6 figure

    State-to-State Rotational Relaxation Rate Constants for CO+Ne from IR-IR Double-Resonance Experiments: Comparing Theory to Experiment

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    IR-IR double-resonance experiments were used to study the state-to-state rotational relaxation of CO with Ne as a collision partner. Rotational levels in the range Ji=2-9 were excited and collisional energy transfer of population to the levels Jf=2-8 was monitored. The resulting data set was analyzed by fitting to numerical solutions of the master equation. State-to-state rate constant matrices were generated using fitting law functions. Fitting laws based on the modifed exponential gap (MEG) and statistical power exponential gap (SPEG) models were used; the MEG model performed better than the SPEG model. A rate constant matrix was also generated from scattering calculations that employed the ab initio potential energy surface of McBane and Cybulski [J. Chem. Phys. 110, 11 734 (1999)]. This theoretical rate constant matrix yielded kinetic simulations that agreed with the data nearly as well as the fitted MEG model and was unique in its ability to reproduce both the rotational energy transfer and pressure broadening data for Ne-CO. The theoretical rate coefficients varied more slowly with the energy gap than coefficients from either of the fitting laws

    Operation and recovery of a seasonally-loaded UK waste stabilisation pond system

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    An intermittent discharge waste stabilisation pond system was trialled for treatment of a seasonal wastewater load from a campsite. The system showed rapid acclimatisation to incoming load, with chlorophyll-a exceeding 700 mg l?1 within 2 weeks and filtered and unfiltered effluent biochemical oxygen demand below 20 and 30 mg l?1 respectively. Good performance continued for some weeks, after which photosynthetic oxygenation capacity in the first pond was seriously impaired by a shock loading believed to include fatty material. Inflow to the system was suspended and a surface film was broken up, after which the pond recovered within an 8-day period. Laboratory experiments indicated that interventions such as artificial aeration and dilution with effluent had no beneficial effect although mixing may have increased the rate of recovery
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