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Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990–2021 : a systematic analysis for the Global Burden of Disease Study 2021
Get PDF“I expect it as part of the kind of package deal when you sign up to these things”—Motivations and experiences of ghosting
No full textMost online dating users perceive ghosting to be common and expect that there is a chance of being ghosted on online dating platforms (ODPs). The current study extends previous research by gaining qualitative insight into what people believe constitutes ghosting behavior, why people ghost, and how ghosting makes them feel. This study aimed to (a) explore individuals’ motivations to ghost, (b) explore individuals experiences of ghosting, and (c) gather the ghosters views of ghosting definition. A total of 12 online interviews were conducted. All participants had previously ghosted on ODPs and lived in the United Kingdom. Data were analyzed using reflexive thematic analysis. The presented five themes reflect a contextual realist approach, using both semantic and latent coding, and reveal that ghosting is considered the norm on ODP. There are general and specific motivations underpinning ghosting behavior, producing a mixed emotional response from the ghoster. The findings also shed light on how we can better define ghosting, with participants having concerns with the word relationship. Finally, we highlight several protective factors that can minimize the likelihood of ghosting. Based on our findings we suggest that ghosting be defined as being a gradual or sudden one-sided ceasing of communication to end the progress of an interaction with another person. While we found several protective factors that can minimize the likelihood of ghosting, these are unique to the individual and ghosting cannot be abolished as it has become a normative and embedded practice within ODP
Antiviral defense in plant stem cells
No full textUndifferentiated plant and animal stem cells are essential for cell, tissue, and organ differentiation, development, and growth. They possess unusual antiviral immunity which differs from that in specialized cells. By comparison to animal stem cells, we discuss how plant stem cells defend against viral invasion and beyond
Estimating nonlinear heterogeneous agent models with neural networks
Get PDFWe leverage recent advancements in machine learning to develop an integrated method to solve globally and estimate models featuring agent heterogeneity, nonlinear constraints, and aggregate uncertainty. Using simulated data, we show that the proposed method accurately estimates the parameters of a nonlinear Heterogeneous Agent New Keynesian (HANK) model with a zero lower bound (ZLB) constraint. We further apply our method to estimate this HANK model using U.S. data. In the estimated model, the interaction between the ZLB constraint and idiosyncratic income risks emerges as a key source of aggregate output volatility
Strain‐modulated ferromagnetism at an intrinsic van der Waals heterojunction
No full textThe van der Waals interaction enables atomically thin layers of exfoliated 2D materials to be interfaced in heterostructures with relaxed epitaxy conditions, however, the ability to exfoliate and freely stack layers without any strain or structural modification is by no means ubiquitous. In this work, the piezoelectricity of the exfoliated van der Waals piezoelectric α‐In2Se3 is utilized to modify the magnetic properties of exfoliated Fe3GeTe2, a van der Waals ferromagnet, resulting in increased domain wall density, reductions in the transition temperature ranging from 5 to 20 K, and an increase in the magnetic coercivity. Structural modifications at the atomic level are corroborated by a comparison to a graphite/α‐In2Se3 heterostructure, for which a decrease in the Tuinstra‐Koenig ratio is found. Magnetostrictive ferromagnetic domains are also observed, which may contribute to the enhanced magnetic coercivity. Density functional theory calculations and atomistic spin dynamic simulations show that the Fe3GeTe2 layer is compressively strained by 0.4%, reducing the exchange stiffness and magnetic anisotropy. The incorporation of α‐In2Se3 may be a general strategy to electrostatically strain interfaces within the paradigm of hexagonal boron nitride‐encapsulated heterostructures, for which the atomic flatness is both an intrinsic property and paramount requirement for 2D van der Waals heterojunctions
Differential development of antibiotic resistance and virulence between Acinetobacter species
No full textThe two species that account for most cases of Acinetobacter-associated bacteremia in the United Kingdom are Acinetobacter lwoffii, often a commensal but also an emerging pathogen, and Acinetobacter baumannii, a well-known antibiotic-resistant species. While these species both cause similar types of human infection and occupy the same niche, A. lwoffii (unlike A. baumannii) has thus far remained susceptible to antibiotics. Comparatively little is known about the biology of A. lwoffii, and this is the largest study on it conducted to date, providing valuable insights into its behaviour and potential threat to human health. This study aimed to explain the antibiotic susceptibility, virulence, and fundamental biological differences between these two species. The relative susceptibility of A. lwoffii was explained as it encoded fewer antibiotic resistance and efflux pump genes than A. baumannii (9 and 30, respectively). While both species had markers of horizontal gene transfer, A. lwoffii encoded more DNA defense systems and harbored a far more restricted range of plasmids. Furthermore, A. lwoffii displayed a reduced ability to select for antibiotic resistance mutations, form biofilm, and infect both in vivo and in in vitro models of infection. This study suggests that the emerging pathogen A. lwoffii has remained susceptible to antibiotics because mechanisms exist to make it highly selective about the DNA it acquires, and we hypothesize that the fact that it only harbors a single RND system restricts the ability to select for resistance mutations. This provides valuable insights into how development of resistance can be constrained in Gram-negative bacteria
Faecal volatile organic compound analysis in de novo paediatric inflammatory bowel disease by gas chromatography–ion mobility spectrometry : a case–control study
No full textThe gut microbiota and its related metabolites differ between inflammatory bowel disease (IBD) patients and healthy controls. In this study, we compared faecal volatile organic compound (VOC) patterns of paediatric IBD patients and controls with gastrointestinal symptoms (CGIs). Additionally, we aimed to assess if baseline VOC profiles could predict treatment response in paediatric IBD patients. We collected faecal samples from a cohort of de novo therapy-naïve paediatric IBD patients and CGIs. VOCs were analysed using gas chromatography–ion mobility spectrometry (GC-IMS). Response was defined as a combination of clinical response based on disease activity scores, without requiring treatment escalation. We included 109 paediatric IBD patients and 75 CGIs, aged 4 to 17 years. Faecal VOC profiles of paediatric IBD patients were distinguishable from those of CGIs (AUC ± 95% CI, p-values: 0.71 (0.64–0.79), <0.001). This discrimination was observed in both Crohn’s disease (CD) (0.75 (0.67–0.84), <0.001) and ulcerative colitis (UC) (0.67 (0.56–0.78), 0.01) patients. VOC profiles between CD and UC patients were not distinguishable (0.57 (0.45–0.69), 0.87). Baseline VOC profiles of responders did not differ from non-responders (0.70 (0.58–0.83), 0.1). In conclusion, faecal VOC profiles of paediatric IBD patients differ significantly from those of CGIs
Fecal microbiota and volatile metabolome pattern alterations precede late-onset meningitis in preterm neonates
No full textObjective The fecal microbiota and metabolome are hypothesized to be altered before late-onset neonatal meningitis (LOM), in analogy to late-onset sepsis (LOS). The present study aimed to identify fecal microbiota composition and volatile metabolomics preceding LOM. Methods Cases and gestational age-matched controls were selected from a prospective, longitudinal preterm cohort study (born &lt;30 weeks’ gestation) at nine neonatal intensive care units. The microbial composition (16S rRNA sequencing) and volatile metabolome (gas chromatography-ion mobility spectrometry (GC-IMS) and GC-time-of-flight-mass spectrometry (GC-TOF-MS)), were analyzed in fecal samples 1-10 days pre-LOM. Results Of 1397 included infants, 21 were diagnosed with LOM (1.5%), and 19 with concomitant LOS (90%). Random Forest classification and MaAsLin2 analysis found similar microbiota features contribute to the discrimination of fecal pre-LOM samples versus controls. A Random Forest model based on six microbiota features accurately predicts LOM 1-3 days before diagnosis with an area under the curve (AUC) of 0.88 (n=147). Pattern recognition analysis by GC-IMS revealed an AUC of 0.70-0.76 (P&lt;0.05) in the three days pre-LOM (n=92). No single discriminative metabolites were identified by GC-TOF-MS (n=66). Conclusion Infants with LOM could be accurately discriminated from controls based on preclinical microbiota composition, while alterations in the volatile metabolome were moderately associated with preclinical LOM
Deflections of high-content recycled aggregate concrete beams reinforced with GFRP bars and steel fibres
No full textCurrent design guidelines for reinforced concrete (RC) beams reinforced with Fibre Reinforced Polymer (FRP) bars neglect shear and shear crack-induced deflections in the calculation of total deflections. However, shear crack-induced deflections can be up to 25 % of the total deflections of FRP RC beams and thus they need to be considered in the calculations. At the same time, the use of Recycled Aggregate Concrete (RAC) reinforced with steel fibres is becoming more common in construction, but limited research has examined deflections in FRP RAC beams with steel fibres. This article proposes a new approach (based on Eurocode 2) to calculate more accurately the deflections of FRP RAC beams reinforced with steel fibres. To achieve this, nine under-reinforced normal concrete (NC) beams and nine RAC beams were tested in bending in three Series: (I) beams with steel bars as flexural and shear reinforcement, (II) beams with Glass FRP (GFRP) bars as flexural reinforcement and steel bars as shear reinforcement, and (III) beams with GFRP bars as flexural reinforcement and 1 % of steel fibres (by volume). The nine RAC beams were cast with RAC made of 100 % recycled concrete aggregates, a structural option that has received limited attention. The results show that adding steel fibres to beam Series III increased the average load at first cracking by up to 15 % and 17 % compared to Series I and II, respectively. Beam Series II and III were then modelled in Abaqus® to provide further insight into their load-deflection behaviour. It is shown that current approaches can accurately predict crack widths at the serviceability limit state of FRP RAC beams but not at higher load levels. The new approach modifies the Eurocode 2 equation using a factor βr that considers the weaker bond of GFRP bars and the additional shear crack-induced deflections. Compared to existing models, the new proposed approach calculates deflections more accurately and with the lowest average Test/Prediction ratio (T/P = 1.17) and Standard Deviation (SD = 0.11) over all beams in Series II and III
Variable temporal length training for action recognition CNNs
No full textMost current deep learning models are suboptimal in terms of the flexibility of their input shape. Usually, computer vision models only work on one fixed shape used during training, otherwise their performance degrades significantly. For video-related tasks, the length of each video (i.e., number of video frames) can vary widely; therefore, sampling of video frames is employed to ensure that every video has the same temporal length. This training method brings about drawbacks in both the training and testing phases. For instance, a universal temporal length can damage the features in longer videos, preventing the model from flexibly adapting to variable lengths for the purposes of on-demand inference. To address this, we propose a simple yet effective training paradigm for 3D convolutional neural networks (3D-CNN) which enables them to process videos with inputs having variable temporal length, i.e., variable length training (VLT). Compared with the standard video training paradigm, our method introduces three extra operations during training: sampling twice, temporal packing, and subvideo-independent 3D convolution. These operations are efficient and can be integrated into any 3D-CNN. In addition, we introduce a consistency loss to regularize the representation space. After training, the model can successfully process video with varying temporal length without any modification in the inference phase. Our experiments on various popular action recognition datasets demonstrate the superior performance of the proposed method compared to conventional training paradigm and other state-of-the-art training paradigms