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The cerebellar cognitive affective syndrome (CCAS) scale has been developed to screen for possible cognitive and affective impairments in cerebellar patients, but previous studies stressed concerns regarding insufficient specificity of the scale. Also, direct comparisons of CCAS scale performance between cerebellar patients with and without CCAS are currently lacking. The aim of this study was to evaluate the validity of the CCAS scale in cerebellar patients.
Method:
In this study, cerebellar patients with CCAS (n = 49), without CCAS (n = 30), and healthy controls (n = 32) were included. The Dutch/Flemish version of the CCAS scale was evaluated in terms of validity and reliability using an extensive neuropsychological assessment as the gold standard for CCAS. Correlations were examined between the CCAS scale and possible confounding factors. Additionally, a correction for dysarthria was applied to timed neuropsychological tests to explore the influence of dysarthria on test outcomes.
Results:
Cerebellar patients with CCAS performed significantly worse on the CCAS scale compared to cerebellar controls. Sensitivity was acceptable, but specificity was insufficient due to high false-positive rates. Correlations were found between outcomes of the scale and both education and age. Although dysarthria did not affect the validity of the CCAS scale, it may influence timed neuropsychological test outcomes.
Conclusions:
Evaluation of the CCAS scale revealed insufficient specificity. Our findings call for age- and education-dependent reference values, which may improve the validity and usability of the scale. Dysarthria might be a confounding factor in timed test items and should be considered to prevent misclassification.
The Mental Health Bill, 2025, proposes to remove autism and learning disability from the scope of Section 3 of the Mental Health Act, 1983 (MHA). The present article represents a professional and carer consensus statement that raises concerns and identifies probable unintended consequences if this proposal becomes law. Our concerns relate to the lack of clear mandate for such proposals, conceptual inconsistency when considering other conditions that might give rise to a need for detention and the inconsistency in applying such changes to Part II of the MHA but not Part III. If the proposed changes become law, we anticipate that detentions would instead occur under the less safeguarded Deprivation of Liberty Safeguards framework, and that unmanaged risks will eventuate in behavioural consequences that will lead to more autistic people or those with a learning disability being sent to prison. Additionally, there is a concern that the proposed definitional breadth of autism and learning disability gives rise to a risk that people with other conditions may unintentionally be unable to be detained. We strongly urge the UK Parliament to amend this portion of the Bill prior to it becoming law.
Blast injuries can occur by a multitude of mechanisms, including improvised explosive devices (IEDs), military munitions, and accidental detonation of chemical or petroleum stores. These injuries disproportionately affect people in low- and middle-income countries (LMICs), where there are often fewer resources to manage complex injuries and mass-casualty events.
Study Objective:
The aim of this systematic review is to describe the literature on the acute facility-based management of blast injuries in LMICs to aid hospitals and organizations preparing to respond to conflict- and non-conflict-related blast events.
Methods:
A search of Ovid MEDLINE, Scopus, Global Index Medicus, Web of Science, CINAHL, and Cochrane databases was used to identify relevant citations from January 1998 through July 2024. This systematic review was conducted in adherence with PRISMA guidelines. Data were extracted and analyzed descriptively. A meta-analysis calculated the pooled proportions of mortality, hospital admission, intensive care unit (ICU) admission, intubation and mechanical ventilation, and emergency surgery.
Results:
Reviewers screened 3,731 titles and abstracts and 173 full texts. Seventy-five articles from 22 countries were included for analysis. Only 14.7% of included articles came from low-income countries (LICs). Sixty percent of studies were conducted in tertiary care hospitals. The mean proportion of patients who were admitted was 52.1% (95% CI, 0.376 to 0.664). Among all in-patients, 20.0% (95% CI, 0.124 to 0.288) were admitted to an ICU. Overall, 38.0% (95% CI, 0.256 to 0.513) of in-patients underwent emergency surgery and 13.8% (95% CI, 0.023 to 0.315) were intubated. Pooled in-patient mortality was 9.5% (95% CI, 0.046 to 0.156) and total hospital mortality (including emergency department [ED] mortality) was 7.4% (95% CI, 0.034 to 0.124). There were no significant differences in mortality when stratified by country income level or hospital setting.
Conclusion:
Findings from this systematic review can be used to guide preparedness and resource allocation for acute care facilities. Pooled proportions for mortality and other outcomes described in the meta-analysis offer a metric by which future researchers can assess the impact of blast events. Under-representation of LICs and non-tertiary care medical facilities and significant heterogeneity in data reporting among published studies limited the analysis.
Prospective and early-career paleontologists deserve an accurate assessment of employment opportunities in their chosen field of study. Drawing on a wide range of sources, we have produced an admittedly incomplete analysis of the current status and recent trends of permanent academic employment in the discipline. Obtaining more complete longitudinal data on employment trends is a major difficulty; this is a challenge that needs to be addressed. The number of job seekers is far in excess of available positions. There has been a clear erosion in the number of academic paleontologists in the United States, a trend exacerbated in recent years. The decline, in constant dollars, of federal funding for paleontological research has potential strong negative impacts on future hiring. The loss of paleontology positions has also had a deleterious effect on our professional societies, which have seen a loss of regular (professional) membership, although student membership remains strong. These trends also potentially negatively impact efforts to diversify the field. Professional societies need to better coordinate their efforts to address these serious issues. Individual paleontologists also must become more effective advocates for the importance and relevance of our science.
Diamonds are found occasionally in the United States of America. Diamonds from the Prairie Creek lamproite in Arkansas, USA occur within a north to south corridor of Neoproterozoic-to-mid-Cretaceous magmatism that extends across North America. These diamond-bearing lamproites are unusual because they intrude adjacent to sutured and strongly thinned lithosphere rather than stable within-plate settings and the diamonds themselves provide physical evidence of processes related to diamond formation at the cratonic margin. Indeed, A review of previously published geophysical data, isotopic compositions, inclusion suites and inclusion geochemistry suggest most diamonds were formed in subducted and eclogitic rocks within a highly localised diamondiferous lithosphere beneath the cratonic margin.
The morphology and spectroscopic character of 155 diamonds from the Prairie Creek lamproite suggest typical diamond formation conditions in an otherwise thinned continental lithosphere. Most diamonds examined during this investigation have spectroscopic features indicating strong nitrogen aggregation, a history of thermal perturbation and plastic deformation. Nitrogen contents range up to 1882 ppm and the diamonds preserve ∼70% aggregated nitrogen in the B aggregation state. Furthermore, inclusion elastic barometry and time-averaged mantle residence temperatures suggest most Arkansas diamonds formed at 5.2±0.2 GPa and 1205±63°C (1σ). However, a subpopulation of ∼4% of relatively large and inclusion free, colourless, flattened-to-irregular habit Arkansas diamonds are Type IIa with <5 at.ppm nitrogen. Those stones size, morphology, colour and N content might warrant their inclusion in the class of Cullinan-like, Large, Inclusion-Poor, Pure, Irregular and Resorbed or ‘CLIPPIR’ diamonds. Other diamonds examined commonly exhibit physical evidence of plastic deformation, including brown body colour and deformation lamellae.
In RISE, TV46000 once monthly (q1m) or once every 2 months (q2m) significantly extended time to impending schizophrenia relapse. The current study (SHINE, NCT03893825) evaluated the long-term safety, tolerability, and effect of TV46000.
Methods
Patients completing RISE without relapse (rollover) or newly recruited (de novo) were eligible. The de novo and placebo rollover cohorts were randomized 1:1 to q1m or q2m for ≤56 weeks; the TV46000 rollover cohort continued assigned regimen. Exploratory efficacy endpoints included time to impending relapse and patient centered outcomes (PCOs) including Schizophrenia Quality of Life Scale (SQLS).
Results
334 patients were randomized and received TV46000 q1m (n=172) or q2m (n=162), for 202.3 patient-years [PY] of TV-46000 treatment. Treatment-emergent adverse events (AEs) reported for ≥5% of patients were: overall–injection site pain (event rate/100 PY, n [%]; 23.23, 16 [5%]); de novo (n=109)–injection site pain (56.10, 11 [10%]), injection site nodule (16.03, 6 [6%]), blood creatine phosphokinase increased (16.03, 8 [7%]), urinary tract infection (10.69, 7 [6%]); placebo rollover (n=53)–tremor (18.50, 5 [9%]); TV46000 rollover (n=172)–headache (7.97, n=8 [5%]). Serious AEs reported for ≥2 patients were worsening schizophrenia and hyperglycemia. Kaplan– Meier estimates for remaining relapse-free at week 56 were 0.98 (2% risk; q1m) and 0.88 (12%; q2m). SQLS improved for q1m (least-squares mean change [SE], − 2.16 [0.98]) and q2m (− 0.43 [0.98]); other PCOs (5Level EuroQoL 5Dimensions Questionnaire, Personal and Social Performance Scale, Drug Attitudes Inventory 10-item version) remained stable.
Conclusions
TV-46000 had a favorable long-term benefit–risk profile in patients with schizophrenia.
Whole genome sequencing (WGS) can help identify transmission of pathogens causing healthcare-associated infections (HAIs). However, the current gold standard of short-read, Illumina-based WGS is labor and time intensive. Given recent improvements in long-read Oxford Nanopore Technologies (ONT) sequencing, we sought to establish a low resource approach providing accurate WGS-pathogen comparison within a time frame allowing for infection prevention and control (IPC) interventions.
Methods:
WGS was prospectively performed on pathogens at increased risk of potential healthcare transmission using the ONT MinION sequencer with R10.4.1 flow cells and Dorado basecaller. Potential transmission was assessed via Ridom SeqSphere+ for core genome multilocus sequence typing and MINTyper for reference-based core genome single nucleotide polymorphisms using previously published cutoff values. The accuracy of our ONT pipeline was determined relative to Illumina.
Results:
Over a six-month period, 242 bacterial isolates from 216 patients were sequenced by a single operator. Compared to the Illumina gold standard, our ONT pipeline achieved a mean identity score of Q60 for assembled genomes, even with a coverage rate as low as 40×. The mean time from initiating DNA extraction to complete analysis was 2 days (IQR 2–3.25 days). We identified five potential transmission clusters comprising 21 isolates (8.7% of sequenced strains). Integrating ONT with epidemiological data, >70% (15/21) of putative transmission cluster isolates originated from patients with potential healthcare transmission links.
Conclusions:
Via a stand-alone ONT pipeline, we detected potentially transmitted HAI pathogens rapidly and accurately, aligning closely with epidemiological data. Our low-resource method has the potential to assist in IPC efforts.
We study the instability of a dusty simple shear flow where the dust particles are distributed non-uniformly. A simple shear flow is modally stable to infinitesimal perturbations. Also, a band of particles remains unaffected in the absence of any background flow. However, we demonstrate that the combined scenario – comprising a simple shear flow with a localized band of particles – can exhibit destabilization due to their two-way interaction. The instability originates solely from the momentum feedback from the particle phase to the fluid phase. Eulerian–Lagrangian simulations are employed to illustrate the existence of this instability. Furthermore, the results are compared with a linear stability analysis of the system using an Eulerian–Eulerian model. Our findings indicate that the instability has an inviscid origin and is characterized by a critical wavelength below which it is not persistent. We have observed that increasing particle inertia dampens the unstable modes, whereas the strength of the instability increases with the strength of the coupling between the fluid and particle phases.
Singing may be a relative strength for people with dementia, yet little is known of how individuals leverage it as a communicative resource in everyday interaction. This study analyzes how Dan, a man living with vascular dementia, modifies lyrics based on prior talk and the physical environment during interactions with his wife, Morgan. Using Conversation Analysis, I describe the emergent structure of his singing and what it accomplishes. Dan uses singing to do a range of interactional jobs (such as complimenting, complaining, and requesting), and his lyrics are susceptible to evaluation based on their construction and relevance to previous talk. Both participants treat his singing as humorous and creative wordplay, but the laughability of his singing is contingent on how he modifies the formulaic lyrics based on the current discursive context. Thus, singing is a way in which Dan situationally constructs himself as a funny, clever, and sociable person. Dan’s singing also indirectly indexes his close relationship with Morgan by assuming her shared musical knowledge. This analysis contributes to the study of identity construction by people with dementia, the understanding of how people adapt to changes in cognition, and the study of the structure and function of singing in everyday interaction.
The effects of hydrothermal conditions on the sorption and fixation of cesium by various clay minerals and shales were investigated. Hydrothermal heating, which may be expected in a radioactive waste repository, altered the clay minerals and shales and led to a decrease in their cation-exchange capacity. Cesium sorption greatly decreased in micaceous vermiculite and in well-crystallized illites containing vermiculite upon hydrothermal treatment at 400°C and 300 bars pressure due to complete layer collapse. However, poorly crystallized illites heated as above showed either a small increase or only a slight decrease in Cs sorption because of partial layer collapse. These studies show that the decrease in Cs sorption is greater in well-crysallized illites than in poorly crystallized illites when treated similarly under hydrothermal conditions. Hydrothermal heating of Cs-sorbed and Cs-saturated samples increased the amount of Cs fixation in all minerals and shales as a result of collapse of the layers. For example, a sample of the Conasauga shale fixed only 18% of sorbed Cs before treatment but fixed 47% after hydrothermal treatment at 200°C and 300 bars pressure. Thus, hydrothermal conditions in a shale repository may be beneficial after leaked radioactive Cs ions are taken up by clay minerals in shales.
Background: High grade gliomas (HGGs) shed extracellular vesicles (EVs) into the bloodstream. EV-derived RNA (EV-RNA) can be detected in plasma, making it a potential biomarker for HGG recurrence after treatment. We sought to establish a baseline relationship between EV-RNA in plasma and hypervascular HGG tissue on MRI. Methods: Eight patients with a new diagnosis of HGG had measurements of plasma EV-RNA and contemporaneous dynamic susceptibility contrast (DSC) MRI. Patient-specific median signal intensity of corpus callosum (mSI-CC) was determined from 10 measurements on the relative cerebral blood volume (rCBV) map. Tumour tissue with signal intensity > mSI-CC and > 2x, > 3x, > 4x and > 5x mSI-CC was segmented on the rCBV map. EV-RNA plasma concentration was correlated with tissue volumes. Results: Pearson correlation showed a significant positive relationship between EV-RNA plasma concentration and tissue volume with signal intensity > mSI-CC (r(6) = 0.899, p = 0.002). No significant relationship could be detected for progressively smaller tissue volumes with signal intensity > 2x, > 3x, > 4x and > 5x mSI-CC. Conclusions: EV-RNA plasma concentration correlates strongly with the total volume of hypervascular HGG tissue on DSC MRI at baseline and merits further evaluation as a biomarker of tumour behaviour in longitudinal imaging studies.
Background: High-grade gliomas (HGG) present challenges with short post-surgery survival and high progression rates. Extracellular vesicles (EVs) in the tumor microenvironment (TME) contribute to a pro-tumorigenic setting. Investigating Transfer RNA fragments (TfRNA) in HGG patient plasma EVs reveals potential biomarkers and therapeutic targets, shedding light on the molecular landscape for enhanced diagnostic and therapeutic strategies. This study examines TfRNA in 10 HGG patients at diagnosis, offering insights into the molecular landscape for improved management strategies. Methods: The study involved the collection of plasma samples from HGG patients and controls. EVs were isolated from these samples and subsequently analyzed for tfRNA. Results: Analysis of plasma EVs highlighted distinct differences in TfRNA fragments between High-Grade Glioma (HGG) and control samples. HGG EVs showed a global reduction in tRNA content, higher 5’ tfRNA proportions, and increased nuclear tfrna compared to controls. A notable biological marker, elevated in HGG, holds potential as a diagnostic indicator. Conclusions: Our study concludes that High-Grade Gliomas (HGG) demonstrate a global reduction in tfRNA content in plasma extracellular vesicles compared to non-cancer controls, echoing findings in other cancers. Despite this, specific tfRNA molecules in HGG show significant differential expression or sorting into EVs, indicating their potential as future biomarkers or therapeutic targets.
Background: Patients with an acute ischemic stroke (AIS) are selected to receive reperfusion therapy using either computed tomography (CT-CTA) or magnetic brain imaging (MRI). The aim of this study was to compare CT and MRI as the primary imaging modality for AIS patients undergoing EVT. Methods: Data for AIS patients between January 2018 and January 2021 were extracted from two prospective multicenter EVT cohorts: the ETIS registry in France (MRI) and the OPTIMISE registry in Canada (CT). Demographics, procedural data and outcomes were collected. We assessed the association of qualifying imaging (CT vs. MRI) with time metrics and functional outcome. Results: From January 2018 to January 2021, 4059 patients selected by MRI and 1324 patients selected by CT were included in the study. Demographics were similar between the two groups. The median imaging-to-arterial puncture time was 37 minutes longer in the MRI group. Patients selected by CT had more favorable 90-day functional outcomes (mRS 0-2) as compared to patients selected by MRI (48.5% vs 44.4%; adjusted OR (aOR), 1.54, 95%CI 1.31 to 1.80, p<0.001). Conclusions: Patients with AIS undergoing EVT who were selected with MRI as opposed to CT had longer imaging-to-arterial-puncture delays and worse functional outcomes at 90 days.
Obesity is a significant health issue in Aotearoa; effective and pragmatic strategies to facilitate weight loss are urgently required. Growing recognition of the circadian rhythm’s impact on metabolism has popularised diets like time-restricted eating (TRE)(1). The 16:8 TRE method involves limiting food intake to an 8-hour daily eating window and can lead to weight loss without other substantial changes to diet(2). Nonetheless, TRE requires accountability and tolerating hunger for short periods. Continuous glucose monitors (CGM) are small wearable biofeedback devices that measure interstitial glucose levels scanned via smartphones. By providing immediate feedback on the physiological effects of eating and fasting, CGM use may promote adherence to TRE(3). This pilot study aimed to 1) investigate how CGM affects adherence to TRE and 2) assess the feasibility of CGM use while undertaking TRE. This two-arm randomised controlled trial enrolled healthy adults from Dunedin, assigning them to TRE-only or TRE+CGM groups for 14 days. Successful adherence to TRE was defined a priori as maintaining an 8-hour eating window on 80% of days. CGM feasibility was defined a priori as scanning the glucose monitor thrice daily on 80% of days. Secondary outcomes included well-being, anthropometry, glucose levels, and overall TRE and CGM experiences via semi-structured interviews. Twenty-two participants were randomised into two groups: TRE-only (n = 11) and TRE+CGM (n = 11, with n = 2 excluded from analysis post-randomisation for medical reasons). Participants had a diverse range of ethnicities, the mean age was 32 (+/-14.9) years, and 55% were female. The TRE+CGM group adhered to the 8-hour eating window for an average of 10.0 days (range 2-14) compared with 8.6 days (range 2-14) in the TRE-only group. Both groups had similar mean eating window durations of 8.1 hours. Five (56%) participants in the TRE+CGM group achieved the a priori criteria for TRE adherence, compared to 3 (27%) in the TRE-only group. Participants in the TRE+CGM group performed an average of 8.2 (+/-5.6) daily scans, with n = 7 (78%) of participants meeting the a priori CGM feasibility criteria. Neither group reported consistent adverse psychological impacts in DASS-21 and WHO-5 scores. Interviews highlighted that CGM increased hunger tolerance during fasting as participants felt reassured by their normal glucose levels. CGM aided TRE accountability by acting as a biological tracker of food intake. Participants reported that TRE led to improved energy and self-efficacy, a more productive daily routine, and healthier food choices. Promisingly, 72% of participants would use CGM and undertake TRE in future. This study demonstrates that using CGM while undertaking TRE is feasible and can improve adherence by enhancing hunger tolerance and accountability. Overall, participants experienced increased awareness of eating habits and physiological mechanisms. Over the longer term, this simple and synergistic approach may be a helpful weight loss strategy.
Clay minerals and zeolites, candidate backfill minerals for nuclear waste repositories, were treated with saturated NaCl brine and Mg-rich (Mg-Ca-Na-K) brine at 200°C and 300°C for 4 weeks under a confining pressure of 30 MPa. The Al concentrations released in NaCl brine were lower than those in Mg-rich brine at both temperatures indicating that the Mg-rich brine is more acidic than the NaCl brine under these hydrothermal conditions. The Si concentrations in both brines were low because of the relatively acidic conditions developed during the hydrothermal treatment. As determined by X-ray powder diffraction or by specific Cs and Sr sorption measurements, no alteration could be detected in clay minerals treated with NaCl brine at 200°C. Among the zeolites tested, only phillipsite and erionite altered to analcime in NaCl brine at 200°C. Zeolites and most of the clay minerals tested did not alter in the Mg-rich brine treated at 200°C. Vermiculite altered to randomly interstratified vermiculite/K-vermiculite (mica-like) by selective K uptake from the Mg-rich brine.
At 300°C, the clay minerals did not greatly alter, whereas the zeolites altered to analcime and/or albite in the presence of the NaCl brine. In the Mg-rich brine, Al-rich montmorillonite from Wyoming did not alter, whereas Al-poor montmorillonite from Texas altered to randomly interstratified montmorillonite/ illite at 300°C. Vermiculite collapsed to form K-vermiculite (~ 10.2 Å) by the selective uptake of K from the Mg-rich brine at 300°C. Most of the zeolites altered to smectites in the Mg-rich brine at 300°C because of the acidic conditions generated by the hydrolysis of Mg. The selective Cs-sorption Kd decreased from 11,700 for untreated phillipsite to 240 and 15 for the hydrothermally produced analcime/albite mixtures from the phillipsite at 200° and 300°C, respectively, in NaCl brine. These results suggest that montmorillonites and mordenites are relatively more resistant than vermiculite or other zeolites at elevated temperatures and pressures in concentrated hydrothermal brines expected in a salt repository.
Sodium-saturated Wyoming bentonite was hydrothermally reacted at 150° and 250°C for 30 to 180 days to determine smectite alteration rates that might be applied to nuclear-waste repository design. Na-Ca solutions deficient in K were used to determine the role of interlayer cations in the creation of high layer-charge in the smectites. The results provide insight into the mechanism and timing of various steps in the diagenetic alteration of smectite to illite. X-ray powder diffraction (XRD) analyses of the reacted clay showed little effect on the character of the 17-Å reflection even after 180 days at 250°C. Potassium saturation of these reacted clays and re-examination by XRD indicated collapse of some smectite layers, leaving at most only 60% expandable layers. The development of layer charge sufficient to cause collapse on saturation with a low hydration energy exchange-cation does not require K in the reacting fluid. Rate constants for the illitization reactions as determined by K-saturated collapse are between 1.0 × 10−3 and 2.8 × 10−3/day with activation energies <3.5 kcal/mole. Ca in a Na-silicate-bicarbonate solution slightly reduced the illitization rate constants. These rate constants are higher than expected from extrapolation of studies of beidellite-composition glasses at higher temperatures, but lower than values obtained in studies of natural clays in artificial sea water. The release of Si, Al, and Mg in the 150°C experiments suggests congruent dissolution of the smectite. In contrast, at 250°C the release of Al was not stoichiometric with Si; as little as one half of the relative available Si was released. Rather than different mechanisms for dissolution at the two temperatures, the conclusion is that noncrystalline Al-rich phases formed at greater rates at higher temperatures. The cation-exchange capacities for several of these reacted smectites were significantly less than expected, suggesting a clogging of interlayer sites, perhaps by Al-complexes.
We investigate the effect of particle inertia on the merger of co-rotating dusty vortex pairs at semi-dilute concentrations. In a particle-free flow, the merger is triggered once the ratio of vortex core size to vortex separation reaches a critical value. The vortex pair separation then decreases monotonically until the two cores merge together. Using Eulerian–Lagrangian simulations of co-rotating particle-laden vortices, we show substantial departure from the vortex dynamics previously established in particle-free flows. Most strikingly, we find that disperse particles with moderate inertia cause the vortex pair to push apart to a separation nearly twice as large as the initial separation. During this stage, the drag force exerted by particles ejected out of the vortex cores on the fluid results in a net repulsive force that pushes the two cores apart. Eventually, the two dusty vortices merge into a single vortex with most particles accumulating outside the core, similar to the dusty Lamb–Oseen vortex described in Shuai & Kasbaoui (J. Fluid Mech., vol 936, 2022, p. A8). For weakly inertial particles, we find that the merger dynamics follows the same mechanics as that of a single-phase flow, albeit with a density that must be adjusted to match the mixture density. For highly inertial particles, the feedback force exerted by the particles on the fluid may stretch the two cores during the merger to a point where each core splits into two, resulting in inner and outer vortex pairs. In this case, the merger occurs in two stages where the inner vortices merge first, followed by the outer ones.
To investigate the symptoms of SARS-CoV-2 infection, their dynamics and their discriminatory power for the disease using longitudinally, prospectively collected information reported at the time of their occurrence. We have analysed data from a large phase 3 clinical UK COVID-19 vaccine trial. The alpha variant was the predominant strain. Participants were assessed for SARS-CoV-2 infection via nasal/throat PCR at recruitment, vaccination appointments, and when symptomatic. Statistical techniques were implemented to infer estimates representative of the UK population, accounting for multiple symptomatic episodes associated with one individual. An optimal diagnostic model for SARS-CoV-2 infection was derived. The 4-month prevalence of SARS-CoV-2 was 2.1%; increasing to 19.4% (16.0%–22.7%) in participants reporting loss of appetite and 31.9% (27.1%–36.8%) in those with anosmia/ageusia. The model identified anosmia and/or ageusia, fever, congestion, and cough to be significantly associated with SARS-CoV-2 infection. Symptoms’ dynamics were vastly different in the two groups; after a slow start peaking later and lasting longer in PCR+ participants, whilst exhibiting a consistent decline in PCR- participants, with, on average, fewer than 3 days of symptoms reported. Anosmia/ageusia peaked late in confirmed SARS-CoV-2 infection (day 12), indicating a low discrimination power for early disease diagnosis.
Recent measurements from Mars document X-ray amorphous/nano-crystalline materials in multiple locations across the planet. Despite their prevalence, however, little is known about these materials or what their presence implies for the history of Mars. The X-ray amorphous component of the martian soil in Gale crater has an X-ray diffraction pattern that can be fit partially with allophane (approximately Al2O3⋅(SiO2)1.3–2⋅(H2O)2.5–3), and the low-temperature water-release data are consistent with allophane. The chemical data from Gale crater suggest that other silicate materials similar to allophane, such as Fe-substituted allophane (approximately (Fe2O3)0.01–0.5(Al2O3)0.5–0.99⋅(SiO2)2⋅3H2O), may also be present. In order to investigate the properties of these potential poorly crystalline components of the martian soil, Fe-free allophane (Fe:Al = 0), Fe-poor allophane (Fe:Al = 1:99), and Fe-rich allophane (Fe:Al = 1:1) were synthesized and then characterized using electron microscopy and Mars-relevant techniques, including infrared spectroscopy, X-ray diffraction, and evolved gas analysis. Dissolution experiments were performed under acidic (initial pH values pH0 = 3.01, pH0 = 5.04), near-neutral (pH0 = 6.99), and alkaline (pH0 = 10.4) conditions in order to determine dissolution kinetics and alteration phases for these poorly crystalline materials. Dissolution rates (rdiss), based on the rate of Si release into solution, show that these poorly crystalline materials dissolve approximately an order of magnitude faster than crystalline phases with similar compositions at all pH conditions. For Fe-free allophane, logrdiss = –10.65–0.15 × pH; for Fe-poor allophane, logrdiss = –10.35–0.22 × pH; and for Fe-rich allophane, logrdiss = –11.46–0.042 × pH at 25°C, where rdiss has the units of mol m–2 s–1. The formation of incipient phyllosilicate-like phases was detected in Fe-free and Fe-rich allophane reacted in aqueous solutions with pH0 = 10.4 (steady-state pH ≈ 8). Mars-analog instrument analyses demonstrate that Fe-free allophane, Fe-poor allophane, and Fe-rich allophane are appropriate analogs for silicate phases in the martian amorphous soil component. Therefore, similar materials on Mars must have had limited interaction with liquid water since their formation. Combined with chemical changes expected from weathering, such as phyllosilicate formation, the rapid alteration of these poorly crystalline materials may be a useful tool for evaluating the extent of aqueous alteration in returned samples of martian soils.