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Nowhere to Hide: Radio-faint AGN in the GOODS-N field
No full textContext. Obtaining a census of active galactic nuclei (AGN) activity across cosmic time is critical to our understanding of galaxy evolution and formation. Many AGN classification techniques are compromised by dust obscuration. However, very long baseline interferometry (VLBI) can be used to identify high brightness temperature compact radio emission (> 105 K) in distant galaxies that can only be reliably attributed to AGN activity. Aims. We present the second in a series of papers dealing with the compact radio population in the GOODS-N field. This paper reviews the various multi-wavelength data and AGN classification techniques in the context of a VLBI-detected sample and use these to investigate the nature of the AGN as well as their host galaxies. Methods. Multi-wavelength data from radio to X-ray were compiled for the GOODS-N AGN sample, and fourteen widely used multi-wavelength AGN classification schemes were tested. We discuss and compare the various biases that affect multi-wavelength and VLBI selection. We use the physical interpretation to imply the nature of VLBI-selected AGN and their hosts. Results. Firstly, we find that no single identification technique can identify all VLBI objects as AGN. Infrared colour-colour selection is most notably incomplete. However, the usage of multiple classification schemes can identify all VLBI-selected AGN, independently verifying similar approaches used in other deep field surveys. In the era of large area surveys with instruments such as the SKA and ngVLA, multi-wavelength coverage, which relies heavily upon observations from space, is often unavailable. Therefore, VLBI remains an integral component in detecting AGN of the jetted efficient and inefficient accretion types. Secondly, a substantial fraction (46%) of the VLBI AGN have no X-ray counterpart, which is most likely due to lack of sensitivity in the X-ray band. Thirdly, a high fraction of the VLBI AGN reside in low or intermediate redshift dust-poor early-type galaxies. These most likely exhibit inefficient accretion. Fourthly, A significant fraction of the VLBI AGN reside in symbiotic dusty starburst - AGN systems. Finally, in the Appendix, we present an extensive compilation of the multi-wavelength properties of all the VLBI AGN in GOODS-N
Maintenance of barrier tissue integrity by unconventional lymphocytes
No full textMucosal surfaces, as a first barrier with the environment are especially susceptible to damage from both pathogens and physical trauma. Thus, these sites require tightly regulated repair programs to maintain barrier function in the face of such insults. Barrier sites are also enriched for unconventional lymphocytes, which lack rearranged antigen receptors or express only a limited range of such receptors, such as ILCs (Innate Lymphoid Cells), γδ T Cells and MAIT (Mucosal Associated Invariant T Cells). Recent studies have uncovered critical roles for unconventional lymphocytes in regulating mucosal barrier function, and, in particular, have highlighted their important involvement in barrier repair. The production of growth factors such as amphiregulin by ILC2, and fibroblast growth factors by γδ T cells have been shown to promote tissue repair at multiple barrier sites. Additionally, MAIT cells have been shown to exhibit pro-repair phenotypes and demonstrate microbiota-dependent promotion of murine skin healing. In this review we will discuss how immune responses at mucosal sites are controlled by unconventional lymphocytes and the ways in which these cells promote tissue repair to maintain barrier integrity in the skin, gut and lungs
Spin-valley collective modes of the electron liquid in graphene
No full textWe develop the theory of collective modes supported by a Fermi liquid of electrons in pristine graphene. Under reasonable assumptions regarding the electron-electron interaction, all the modes but the plasmon are over-damped. In addition to the SU(2) symmetric spin mode, these include also the valley imbalance modes obeying a U(1) symmetry, and a U(2) symmetric valley spin imbalance mode. We derive the interactions and diffusion constants characterizing the over-damped modes. The corresponding relaxation rates set fundamental constraints on graphene valley- and spintronics applications
Developing guidance for psychological professionals on inpatient mental health wards during the COVID-19 pandemic
No full textDue to the challenges faced by mental health inpatient psychological professionals working during the COVID-19 pandemic, we aimed to produce guidelines on best practice through consultations with psychological professionals, patients and ward staff
Sorption, swelling and plasticization of PIM-1 in methanol-dimethyl carbonate vapour mixtures
No full textMembranes from PIM-1 represent a promising tool for the efficient recovery of organic components from their vapour mixtures with water or alcohols. To understand the phenomena governing the separation, sorption, swelling and mechanical characteristics were systematically studied for thick PIM-1 films exposed to vapour mixtures of methanol and dimethyl carbonate (DMC). The studied binary vapour mixtures contained 30, 55, 82 and 90 mol.% of methanol and reached 28, 49 and 63 % of the dew point pressure at 40 °C. The separation factor for sorption of vapour mixtures ranged 4.0-7.5, peaked for the azeotropic mixture (82 mol% of methanol) at low saturation (28 % of the dew point pressure), and was significantly contributed by competitive sorption. Furthermore, the tested PIM-1 films exhibited anomalously low volume swelling while their storage modulus remained comparable to that of the pure polymer until exposed to the highly saturated vapours (63 % of the dew point pressure). Raman spectroscopy analysis of PIM-1 swollen by liquid methanol and DMC revealed the pronounced frequency shifts of the C-C vibrations in the aromatic rings and the C-H vibrations in the pentacyclic units. These centres presumably triggered the relaxation of the polymer backbone occurring at high saturations of the vapours. In conclusion, PIM-1 remains highly rigid and selective to DMC in wide ranges of saturation and composition for vapour mixtures of methanol with DMC and is a candidate for effective inversely selective vapour separation membranes
Adaptive lead weighted ResNet trained with different duration signals for classifying 12-lead ECGs
No full textIntroduction: We describe the creation of a ensemble deep neural network architecture to classify cardiac abnormality from 12 lead ECGs. The model was created by the team between a ROC and a heart place for the PhysioNet/Computing in Cardiology Challenge 2020.Methods: ECGs were downsampled to 257 Hz and then set to a consistent duration by randomly clipping or zeropadding the signal to 4096 samples. To learn effective features, we created a modified ResNet with larger kernel sizes that models long-term dependencies. We embeddeda Squeeze-And-Excitation layer into the modified ResNet to learn the importance of each lead, adaptively. A simple constrained grid-search method was applied to deal with class imbalance.Results: Using the bespoke weighted accuracy metric, We achieved a 5-fold cross-validation score of 0.684, sensitivity and specificity of 0.758 and 0.969, respectively. The corresponding result for the hidden test set was 0.672.Conclusion: The proposed prediction model performed well on the validation and hidden test data. Such modelsmay be potentially used for ECG screening or diagnosis
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
Efficient Multi-Objective Gans for Image Restoration
No full textGenerative adversarial networks (GANs) have been widely adopted in many image processing tasks including restoration. In order to further improve quality of generated images, the training objective function needs to incorporate more constraints in addition to the adversarial loss. It can be straightforward to combine various losses in a linear fashion. However, hyperparameter fine-tuning and non-convex loss optimization are challenging problems when combining cost functions in such a manner. Here, we propose an efficient formulation of multiple loss components for training GANs. The proposed method, termed HypervolGAN, not only provides an efficient alternative for simultaneous cost optimization, but also boosts model performance in terms of improving generated image quality without excess computation. We further introduce two image-quality-measure based loss components to the GANs specifically for image restoration. Extensive evaluations and results on various benchmark datasets validate the effectiveness of the proposed methods
A Multi-Objective Multi-Type Facility Location Problem for the Delivery of Personalised Medicine
No full textAdvances in personalised medicine targeting specific subpopulations and individuals pose a challenge to the traditional pharmaceutical industry. With a higher level of personalisation, an already critical supply chain is facing additional demands added by the very sensitive nature of its products. Nevertheless, studies concerned with the efficient development and delivery of these products are scarce. Thus, this paper presents the case of personalised medicine and the challenges imposed by its mass delivery. We propose a multi-objective mathematical model for the location-allocation problem with two interdependent facility types in the case of personalised medicine products. We show its practical application through a cell and gene therapy case study. A multi-objective genetic algorithm with a novel population initialisation procedure is used as solution method
Randomized phase 2 study of the addition of ramucirumab or merestinib to standard first line therapy for advanced or metastatic biliary tract cancer
No full textBackground: Biliary tract cancers (BTC) are aggressive, rare GI malignancies with poor outcomes; approximately half of patients succumb to disease within 1 year. We evaluated the efficacy and safety of ramucirumab or merestinib with first-line cisplatin-gemcitabine in patients with advanced BTC.Methods: This global, double-blind, phase 2 study was carried out in 81 sites across 18 countries. Eligible patients who were treatment naïve, ≥18 years, with non-resectable, recurrent or metastatic biliary tract adenocarcinoma, an ECOG performance status of 0 or 1, received cisplatin-gemcitabine (25mg/m2-1000mg/m2) (day-1 and day-8, every 21-days, 8-cycles) and were randomized 2:1:2:1 to receive either intravenous (IV) ramucirumab 8mg/kg/placebo (same cycle) or oral merestinib 80mg/oral placebo (daily) until disease progression. Randomization was done by an interactive web response system; stratified by primary tumor site, geographic region and metastatic disease. Primary objective was investigator-assessed PFS (intention-to-treat population). This study, registered at ClinicalTrials.gov, NCT02711553, is ongoing for long-term follow-up.Findings: 309 patients were randomized (25-May-2016 through 08-August-2017); 106 to the RAM arm, 102 to the MER arm and 101 to the placebo arm; 306 received ≥1 treatment dose. Median PFS (80% CI) was 6.47 (5.7-7.1) months in ramucirumab arm (n=106), 6.97 (6.2-7.1) months in merestinib arm (n=102), and 6.64 (5.6-6.8) months in pooled placebo arm (n=101) (ramucirumab vs placebo: HR 1.12, 80% CI 0.90-1.40; merestinib vs placebo: HR 0.92, 80% CI 0.73-1.15). Median follow-up time (IQR) (data cutoff 16-February-2018.) was 10.9 (8.1-14.1) months. Grade ≥3 adverse events (AEs) occurred in 90 (86.5%) of 104 patients in ramucirumab, 87 (85.3%) of 102 in merestinib, compared to 81 (81.0%) of 100 patients in placebo; most commonly neutropenia (ramucirumab: 51 [49.0%]; merestinib: 48 [47.1%]; placebo: 33 [33.0%]), thrombocytopenia (ramucirumab: 36 [34.6%]; merestinib: 19 [18.6%]; placebo: 17 [17.0%]) and anemia (ramucirumab: 28 [26.9%]; merestinib: 16 [15.7%]; placebo: 19 [19.0%]). Approximately half the patients reported serious AEs (ramucirumab: 53 [51.0%]; merestinib: n=56 [54.9%]; placebo: n=48 [48.0%]). Treatment-related deaths, deemed related by the investigator, occurred in 1 patient in RAM arm (cardiac arrest) and 2 patients in MER arm (1 pulmonary embolism and 1 sepsis). Interpretation: Adding ramucirumab or merestinib to first-line cisplatin-gemcitabine was well-tolerated, with no new safety signals but did not improve PFS in patients with molecularly-unselected advanced BTC. The role of these targeted inhibitors remains investigational, highlighting the need for further understanding of biliary tract malignancies and the contribution of molecular selection