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Quantity and type of peer-reviewed evidence for popular free medical apps: cross-sectional review
No full textIntroduction: – Mobile apps are being increasingly used as a tool to deliver clinical care. Evidence of efficacy for such apps varies, and appropriate levels of evidence may depend on the app's intended use. The UK's National Institute for Health and Care Excellence (NICE) recently developed an evidence standards framework, aiming to explicitly set out the required standards of evidence for different categories of digital health technologies. To determine current compliance with the evidence standards framework, the current study quantified the amount and type of peer-reviewed evidence associated with a cross-section of popular medical apps. Methods: – Apps were identified by selecting the top 100 free medical apps in the Apple App Store and all free apps in the NHS Apps Library. Each app was assigned to one of the four tiers (1, 2, 3a, 3b) in the NICE evidence standards framework. For each app, we conducted searches in Ovid-MEDLINE, Web of Science, Google Scholar, and via manufacturer websites to identify any published articles that assessed the app. This allowed us to determine our primary outcome, whether apps in tiers 3a/3b were more likely than apps in tier 1/2 to be associated with academic peer-reviewed evidence. Results: – We reviewed 125 apps in total (Apple App Store (n = 72), NHS Apps Library (n = 45), both (n = 8), of which 54 were categorized into the higher evidence standards framework tiers, 3a/3b. After screening, we extracted 105 relevant articles which were associated with 25 of the apps. Only 6 articles, pertaining to 3 apps, were reports of randomised controlled trials. Apps in tiers 3a/3b were more likely to be associated with articles than apps in lower tiers (χ 2 = 5.54, p =.01). The percentage of tier 3a/3b apps with associated articles was similar for both the NHS Apps Library (10/28) and Apple App store (7/24), (χ 2 = 0.042, p =.84). Discussion: – Apps that were in higher tiers 3a and 3b, indicating higher clinical risk, were more likely to have an associated article than those in lower categories. However, even in these tiers, supporting peer-reviewed evidence was missing in the majority of instances. In our sample, Apps from the NHS Apps Library were more no more likely to have supporting evidence than popular Apple App Store apps. This is of concern, given that NHS approval may influence uptake of app usage.</p
Switching Polymorph Stabilities with Impurities Provides A Thermodynamic Route to Benzamide Form III
No full textAlmost 200 years ago, benzamide was reported as polymorphic with two of its forms (II and III) found to be of difficult crystallisation. In a recent study, it was shown that benzamide form I can easily convert into benzamide form III with mechanochemistry in the presence of nicotinamide. Here we show, experimentally and computationally, that this transformation is the result of a thermodynamic switch between these two polymorphic forms driven by the formation of solid solutions with small amounts of nicotinamide. The presence of nicotinamide in the crystallisation environment promotes the robust and exclusive crystallisation of the elusive form III. These results represent a promising route to the synthesis andutilisation of elusive polymorphs of pharmaceutical interest
Quantifying the Effects of MV-LV Distribution Network Constraints and DER Reactive Power Capabilities on Aggregators
No full textDistributed energy resources (DER), such as photovoltaic systems and batteries, are becoming common among households. Although the main objective is reducing electricity imports (bills), they could also provide system-level services via an aggregator. However, the more DER provide services, the more important is ensuring that the corresponding operation does not result in network issues. To help DER aggregators understand the implications of network constraints, this work proposes an AC optimal power flow-based methodology to quantify the effects that three-phase low voltage (LV) and medium voltage (MV) network constraints can have on the volume of services that can be provided for a given horizon, and the potential benefits from using DER reactive power capabilities. Using a convex multi-period formulation that avoids binary variables for batteries and incorporates voltage-dependent load models, the methodology maximizes DER exports (services) for service-related periods and household self-consumption for other periods (reducing bills). Different service periods are assessed to explore the extent of services throughout the day. Results using a realistic UK MV-LV network with 2,400+ households, show that aggregator services can be highly overestimated when neglecting MV-LV constraints, these depend on voltage-demand load characteristics, and that exploiting DER reactive power capabilities can significantly unlock further services
Impaired regulatory T cell control of astroglial overdrive and microglial pruning in schizophrenia
No full textIt is widely held that schizophrenia involves an active process of peripheral inflammation that induces or reflects brain inflammation with activation of microglia, the brain’s resident immune cells. However, recent in vivo radioligand binding studies and large-scale transcriptomics in post-mortem brain report reduced markers of microglial inflammation. The findings suggest a contrary hypothesis; that microglia are diverted into their non-inflammatory synaptic remodelling phenotype that interferes with neurodevelopment and perhaps contributes to the relapsing nature of schizophrenia. Recent discoveries on the regulatory interactions between micro- and astroglial cells and meningeal immune regulatory T cells (Tregs) cohere with clinical omics data to suggest that: i) activated astrocytes mediate the shift in microglial phenotype via the production of transforming growth factor-beta, which also contributes to the disturbances of dopamine and GABA function in schizophrenia, and ii) systemically impaired functioning of Treg cells contributes to the dysregulation of glial function, the low-grade peripheral inflammation, and the hitherto unexplained predisposition to auto-immunity and reduced lifeexpectancy in schizophrenia, including greater COVID-19 mortality
A compact core-jet structure in the changing-look Seyfert NGC 2617
No full textThe nearby face-on spiral galaxy NGC2617 underwent an unambiguous ‘inside-out’ multi-wavelength outburst in Spring 2013, and a dramatic Seyfert type change probably between 2010 and 2012, with the emergence of broad optical emission lines. To search for the jet activity associated with this variable accretion activity, we carried out multi-resolution and multi-wavelength radio observations. Using the very long baseline interferometric (VLBI) observations with the European VLBI Network (EVN) at 1.7 and 5.0 GHz, we find that NGC 2617 shows a partially synchrotron self-absorbed compact radio core with a significant core shift, and an optically thin steep-spectrum jet extending towards the north up to about two parsecs in projection.We also observed NGC 2617 with the electronic Multi-Element Remotely Linked Interferometer Network (e-MERLIN) at 1.5 and 5.5 GHz, and revisited the archival data of the Very Large Array (VLA) and the Very Long Baseline Array (VLBA). The radio core had a stable flux density of 1.4 mJy at 5.0 GHz between 2013 June and 2014 January, in agreement with the expectation of a supermassive black hole in the low accretion rate state. The northern jet component is unlikely to be associated with the ‘inside-out’ outburst of 2013. Moreover, we report that most optically selected changing-look AGN at 푧 Ÿ 0•83 are sub-mJy radio sources in the existing VLA surveys at 1.4 GHz, and it is unlikely that they are more active than normal AGN at radio frequencies
The fetal umbilical artery Doppler as a tool for universal third trimester screening: a systematic review and meta-analysis of diagnostic test accuracy.
No full textThe objective of this study was to investigate the accuracy of universal third trimester umbilical artery (UA) Doppler to predict adverse pregnancy outcome at term. We searched Medline, EMBASE, the Cochrane library and ClinicalTrials.gov from inception to October 2020 and we also analyzed previously unpublished data from a prospective cohort study of nulliparous women, the Pregnancy Outcome Prediction (POP) study. We included studies that performed a third-trimester ultrasound scan in unselected, low or mixed risk populations, excluding studies which only included high risk pregnancies. Meta-analysis was performed using the hierarchal summary receiver operating characteristic curve (HSROC) analysis and bivariate logit-normal models. We identified 13 studies (including the POP study) involving 67,764 pregnancies which met our inclusion criteria. The overall quality was variable and only six studies (N= 5777 patients) blinded clinicians to the UA Doppler result. The summary sensitivity and positive likelihood ratio (LR) for small for gestational age (SGA; birthweight <10th centile) were 21.7% (95% CI 13.2-33.6%) and 2.65 (95% CI 1.89-3.72) respectively. The summary positive LR for NICU admission and metabolic acidosis were 1.35 (95% CI 0.93-1.97) and 1.34 (95% CI 0.86-2.08) respectively. The results were similar in the POP study: associations with SGA (positive LR 2.66 [95% CI 2.11-3.36]) and severe SGA (birthweight <3rd centile; positive LR 3.27 [95% CI 2.29-4.68]) but no statistically significant association with neonatal morbidity. We conclude that third trimester UA Doppler has moderate predictive accuracy for small for gestational age but not for indicators of neonatal morbidity in unselected and low risk pregnancies
High Flux Thin Film Composite PIM-1 Membranes for Butanol Recovery: Experimental Study and Process Simulation
No full textThin film composite (TFC) membranes of the prototypical polymer of intrinsic microporosity (PIM-1) have been prepared by dip coating on a highly porous electrospun polyvinylidene fluoride (PVDF) nanofibrous support. Prior to coating, the support was impregnated in a non-solvent to avoid the penetration of PIM-1 inside the PVDF network. Different non-solvents were considered and the results were compared with those of the dry support. When applied for the separation of n-butanol/water mixtures by pervaporation (PV), the developed membranes exhibited very high permeate fluxes, in the range of 16.1-35.4 kg m-2 h-1, with an acceptable n-butanol/water separation factor of about 8. The PV separation index (PSI) of the prepared membranes is around 115, which is among the highest PSI values that have been reported so far. Hybrid PV-distillation systems have been designed and modelled in Aspen HYSYS using Aspen Custom Modeler for setting up the PIM-1 TFC and commercial PDMS membranes as a benchmark. The butanol recovery cost for the hybrid systems is compared with a conventional standalone distillation process used for n-butanol/water separation and a 10% reduction in recovery cost was obtained
First deep images catalogue of extended IPHAS PNe
No full textWe present the first instalment of a deep imaging catalogue containing 58 True, Likely and Possible extended PNe detected with the Isaac Newton Telescope Photometric Ha Survey (IPHAS). The three narrow-band filters in the emission lines of Ha, [N II] l6584 Å, and [O III] l5007 Å used for this purpose allowed us to improve our description of the morphology and dimensions of the nebulae. In some cases even the nature of the source has been reassessed. We were then able to unveil new macro- and micro-structures, which will without a doubt contribute to a more accurate analysis of these PNe. It has been also possible to perform a primary classification of the targets based on their ionization level. A Deep Learning classification tool has also been tested. We expect that all the PNe from the IPHAS catalogue of new extended planetary nebulae will ultimately be part of this deep Ha, [N II] and [O III] imaging catalogue
Wasserstein distance error bounds for the multivariate normal approximation of the maximum likelihood estimator
No full textWe obtain explicit p-Wasserstein distance error bounds between the distribution of the multi-parameter MLE and the multivariate normal distribution. Our general bounds are given for possibly high-dimensional, independent and identically distributed random vectors. Our general bounds are of the optimal O(n-1=2) order. Explicit numerical constants are given when p 2 (1; 2], and in the case p > 2 the bounds are explicit up to a constant factor that only depends on p. We apply our general bounds to derive Wasserstein distance error bounds for the multivariate normal approximation of the MLE in several settings; these being singleparameter exponential families, the normal distribution under canonical parametrisation, and the multivariate normal distribution under non-canonical parametrisation. In addition, we provide upper bounds with respect to the bounded Wasserstein distance when the MLE is implicitly dened
