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Constraints on solar wind density and velocity based on coronal tomography and Parker Solar Probe measurements
Get PDFPrevious work has established an empirical relationship between densities gained from coronal rotational
tomography near the ecliptic plane with solar wind outflow speeds at heliocentric distance r₀ = 8R⊙. This work
aims to include solar wind acceleration, and thus velocity profiles out to 1 au. Inner boundary velocities are given
as a function of normalized tomographic densities, ρN, as V₀ = (75 * ᵉ⁻[⁵.²⁺ρᴺ] + 108), and typically range from
100 to 180 km s−1. The subsequent acceleration is defined as V(r) = V₀(1+αIP[1-e⁽⁻[ʳ⁻ʳ⁰]/ʳᴴ⁾]), with αIP ranging between 1.75 and 2.7, and rH between 50 and 35 R⊙ dependent on V0. These acceleration profiles
approximate the distribution of in situ measurements by Parker Solar Probe (PSP) and other measurements at 1 au.
Between 2018 November and 2021 September these constraints are applied using the HUXt model and give good
agreement with in situ observations at PSP, with a ∼6% improvement compared with using a simpler constant
acceleration model previously considered. Given the known tomographical densities at 8 R⊙, we extrapolate
density to 1 au using the model velocities and assuming mass flux conservation. Extrapolated densities agree well
with OMNI measurements. Thus coronagraph-based estimates of densities define the ambient solar wind outflow
speed, acceleration, and density from 8 R⊙ to at least 1 au. This sets a constraint on more advanced models, and a
framework for forecasting that provides a valid alternative to the use of velocities derived from magnetic field
extrapolations
Co-designing an intervention using the COM-B model to change an eating behaviour in people living with achalasia
Get PDFBackground: Achalasia is a rare motility disorder affecting the oesophagus, leading to difficulties with eating and drinking. Participants in previous studies reported that they needed more social, clinical and behavioural support in the long-term management of achalasia. This study, therefore aimed to 1) identify the most challenging eating behaviour for people living with achalasia and 2) co-design a behaviour change intervention to help address the challenges they experience.
Methods: This study used a qualitative approach involving online focus groups. The COM-B model was the theoretical framework, with behaviour change techniques (BCTs) as the active ingredients that target a mixture of capability, opportunity and/or motivation. Three focus groups were undertaken to obtain
a range of input from different people living with achalasia. Participants in this study identified the target behaviour, prioritised the different BCTs which most resonated with them to design an intervention and decided on the mode of delivery. The research team analysed the techniques that helped participants with their eating behaviour using the COM-B model as a framework to create the intervention.
Results: The 24 participants in this study identified “eating in a social setting” as the target behaviour for the intervention. A workbook that can be personalised by the individual was the most suitable intervention. The workbook structure aligns with the constructs of the COM-B model. It includes reflection, activities and goal-setting sections based on what was indicated to be useful for the majority of the participants. Key techniques to overcome the challenges with eating in a social setting included social support, regulation to reduce negative emotions, goals and planning.
Conclusion: Using a focus group approach with the COM-B model as the theoretical framework, the participants in this study developed an intervention to support people living with achalasia. In order to achieve long-term behaviour change, engagement with a personalised workbook could facilitate eating in a social setting. Future work will need to pilot the workbook to ensure it can support people to improve their quality of life and complement the ongoing care they receive from health services
Earth Virtualization Engines (EVE)
Get PDFTo manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change
How uncertain and observable are marine ecosystem indicators in shelf seas?
Get PDFOperational analysis and forecast products of shelf sea biogeochemistry often lack reliable information on uncertainty. This is problematic, as good quality uncertainty information is both requested by the product end-users and essential for data assimilation. To address this problem we developed a quality-assessed ensemble representation of many leading sources of uncertainty in a coupled marine physical-biogeochemical model of the North-West European Shelf. Based on these ensembles we have estimated the uncertainty of several marine ecosystem health indicators (MEHIs), acting as proxies for biological productivity, phytoplankton community structure, trophic fluxes, deoxygenation, acidification and carbon export. We have also evaluated how observable these MEHIs are from the most widely available observations of total chlorophyll (mostly from the surface), highlighting those MEHIs and locations that need to be better monitored. Our results show that the most uncertain and the least observable MEHI is the phytoplankton community composition, highlighting the value of its observations (and their assimilation) particularly in the UK regional waters. We demonstrate that daily operational estimates of the other MEHIs, produced by the Met Office, are fairly well constrained. We also quantify how much MEHI uncertainties are reduced when one substantially coarsens the MEHI spatial and temporal resolution, as in the global and/or climate applications
Empirical investigation of different factor structures for the eating disorder examination–questionnaire in adult women with anorexia nervosa
Get PDFThe Eating Disorder Examination–Questionnaire (EDE-Q) is a widely used self-report measure of eating pathology. Despite widespread use, investigations of its factor structure have proved inconclusive and rarely supported the “original” interpretation. The current study evaluates several proposed factor solutions of the EDE-Q using latent variable analysis in a sample of adult women with anorexia nervosa (AN). A total of 804 patients from a specialist treatment center in the United States participated in the study. Confirmatory factor analysis was conducted on 22 EDE-Q items assessing attitudinal features of eating pathology. Findings suggested that three full-item versions (none of which was the “original” interpretation) fit the data adequately, with a brief, seven-item version showing excellent fit. The study is one of the first to examine this within a sample of women with AN and provides an empirical foundation for how best to use the EDE-Q among clinical and research participants with AN. Findings suggest that the “original” factor structure lacks structural validity in women with AN. Its use should generally be discouraged, and future work on screening and treatment outcomes might consider the EDE-Q7
Surface water temperature observations and ice phenology estimations for 1.4 million lakes globally
Get PDFWater temperature and ice cover are critical characteristics of the ecological, biogeochemical, and physical functioning of a lake. Site-specific observations of temperature and ice, however, are not available for most lakes in the world. Yet this information is crucial to understanding the global role of lakes in the functioning of the bio- and hydrosphere. Here, we present the LakeTEMP dataset, referring to the ~1.4 million lakes globally of the HydroLAKES database with a surface area exceeding 0.1 km2, and consisting of two subsets: (1) an observational dataset that contains lake surface water temperatures (LSWTs), derived from Landsat 8 thermal radiance observations between 2013 and 2021 extracted at the lake center points; and (2) a dataset with monthly and yearly LSWT summary statistics and predictions of average yearly ice cover durations, interpolated from the observational dataset using seasonal trendlines. All observations underwent extensive quality control and filtering, based on outlier detection, overlapping imagery removal, and the removal of observations taken from dry lake beds. Validation of the LSWT observations was carried out with in-situ data and yielded an R^2, RMSE and median of differences of 0.93, 1.71°C and 0.42°C, respectively. The global average yearly LSWT is 6.3°C, assuming 0°C during times of presumed ice cover, and 12.4°C when only considering periods of open water. About 8% of all lakes never freeze, ~6% have short or sporadic freezing periods, and ~86% freeze every year, corresponding to an estimated proportion of global lake surface area of 23%, 20%, and 57%, respectively. The warmest lakes in the
world (average temperatures of up to 36°C) are all artificial lakes used in the power plant, mining, salt
extraction, and aquaculture industries. LakeTEMP fills a crucial spatial data gap in large-scale limnological research, especially for the incorporation of small lakes and understudied geographies of remote regions.
Moreover, easy linkage to other large-scale datasets that use the unique lake identifiers from HydroLAKES, most
notably the LakeATLAS database (56 hydro-environmental variables for each lake including anthropogenic influences), allows to explore characteristics that may be correlated to or affected by LSWT and ice cover. The data
are in an analysis-ready format and openly available at https://doi.org/10.6084/m9.figshare.23844660
Down the drain: reconstructing social practice from the content of two sewers in a Late Antique bathhouse in Jerash, Jordan
Get PDFThis contribution examines social practices in the Central Bathhouse in Jerash in Late Antiquity based on the ceramic assemblage, vessel glass, faunal remains, and small finds retrieved from two sections of the bathhouse’s sewer. We argue that although the bathhouse underwent significant architectural alterations from its construction in the 4th c. CE to its abandonment in the late 7th, the activities taking place inside the building remained largely the same. Our study shows that even towards the end of the bathhouse’s lifespan, bodily grooming remained integral to the bathing experience, while food and drink were consumed on the premises even though the bathing facilities had been reduced to a bare minimum. The faunal remains indicate the type of food consumed, while the small finds illustrate a lively environment where gaming and gambling took place in a social
space frequented by men, women, and children
Cocoa pod husk-derived organic soil amendments differentially affect soil fertility, nutrient leaching, and greenhouse gas emissions in cocoa soils
Get PDFThe depletion of soil nutrients and decline in yields on cocoa farms in west Africa over time force farmers to abandon their farms and look for new fertile land, thereby contributing to deforestation. Cocoa pod husks (CPH) are a major farm waste representing considerable export of nutrients from cocoa soils, particularly P and K. Here, the impacts of soil amendment with raw CPH residues, CPH compost, CPH biochar, or a CPH compost-biochar mixture on soil fertility, greenhouse gas (GHG) emissions, and nutrient losses via leaching were assessed in two laboratory experiments using two major soil types used for cocoa cultivation in Ghana (an acidic Ferralsol and an alkaline Nitisol). In Experiment 1, soil nutrient availability and CO2 and N2O emissions were quantified, whereas simulation and quantification of nutrient leaching were conducted in Experiment 2. Soil pH increased from 4.8 and 8.6 by 1.4- and 1.1-folds on average in amended Ferralsols and Nitisols, respectively. Soil electrical conductivity increased in soils amended with CPH compost and/or biochar. Addition of raw CPH caused remarkable microbial immobilisation of N and reduced N availability and leaching, whereas CPH compost and/or biochar addition increased soil nitrate availability but reduced soil ammonium availability. Leaching of Ca in Nitisols was reduced when CPH biochar was included in the soil amendment. While soil K availability increased in all amended soils, most notably when CPH biochar was included, soil P and Ca availabilities were greatest where CPH compost was included. Soil total GHG emission (CO2 plus N2O) increased in all amended Ferralsols and the Nitisols amended with CPH compost or raw CPH, with the latter remarkably increasing soil CO2 emission by up to 14.8-folds. Compared to sole CPH compost amendment, CPH compost-biochar mixture amendment reduced soil total GHG emission and N and P leaching. These findings show that composted and/or pyrolysed CPH can be judiciously used to enhance soil fertility in cocoa farms, particularly in acidic soils. Pyrolysed CPH is especially beneficial for reducing soil nutrient leaching and GHG emissions and thus for increasing the sustainability of cocoa production in Ghana and west Africa
The seventh blind test of crystal structure prediction: structure ranking methods
Get PDFA seventh blind test of crystal structure prediction has been organized by the Cambridge Crystallographic Data Centre. The results are presented in two parts, with this second part focusing on methods for ranking crystal structures in order of stability. The exercise involved standardized sets of structures seeded from a range of structure generation methods. Participants from 22 groups applied several periodic DFT-D methods, machine learned potentials, force fields derived from empirical data or quantum chemical calculations, and various combinations of the above. In addition, one non-energy-based scoring function was used. Results showed that periodic DFT-D methods overall agreed with experimental data within expected error margins, while one machine learned model, applying system-specific AIMnet potentials, agreed with experiment in many cases demonstrating promise as an efficient alternative to DFT-based methods. For target XXXII, a consensus was reached across periodic DFT methods, with consistently high predicted energies of experimental forms relative to the global minimum (above 4 kJ mol−1 at both low and ambient temperatures) suggesting a more stable polymorph is likely not yet observed. The calculation of free energies at ambient temperatures offered improvement of predictions only in some cases (for targets XXVII and XXXI). Several avenues for future research have been suggested, highlighting the need for greater efficiency considering the vast amounts of resources utilized in many cases
Tau-mediated synaptic dysfunction is coupled with HCN channelopathy
Get PDFINTRODUCTION: In tauopathies, altered tau processing correlates with impairments
in synaptic density and function. Changes in hyperpolarization-activated cyclic
nucleotide-gated (HCN) channels contribute to disease-associated abnormalities in
multiple neurodegenerative diseases.
METHODS: To investigate the link between tau and HCN channels, we performed
histological, biochemical, ultrastructural, and functional analyses of hippocampal tissues
from Alzheimer’s disease (AD), age-matched controls, Tau35 mice, and/or Tau35
primary hippocampal neurons.
RESULTS: Expression of specific HCN channels is elevated in post mortem AD hippocampus.
Tau35 mice develop progressive abnormalities including increased phosphorylated
tau, enhanced HCN channel expression, decreased dendritic branching,
reduced synapse density, and vesicle clustering defects. Tau35 primary neurons show
increased HCN channel expression enhanced hyperpolarization-induced membrane
voltage “sag” and changes in the frequency and kinetics of spontaneous excitatory
postsynaptic currents.
DISCUSSION: Our findings are consistent with a model in which pathological changes
in tauopathies impact HCN channels to drive network-wide structural and functional
synaptic deficits