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Kinetic tomography of the Galactic plane within 1.25 kiloparsecs from the Sun. The interstellar flows revealed by HI and CO line emission and 3D dust
No full textWe present a reconstruction of the line-of-sight motions of the local interstellar medium (ISM) based on the combination of a model of the three-dimensional dust density distribution within 1.25 kpc from the Sun and the H I and CO line emission within Galactic latitudes |b| ≤ 5°. We used the histogram of oriented gradient (HOG) method, a computer vision technique for evaluating the morphological correlation between images, to match the plane-of-the-sky dust distribution across distances with the atomic and molecular line emission. We identified a significant correlation between the 3D dust model and the line emission. We employed this correlation to assign line-of-sight velocities to the dust across density channels and produce a face-on map of the local ISM radial motions with respect to the local standard of rest (LSR). We find that most of the material in the 3D dust model follows the large-scale pattern of Galactic rotation; however, we also report local departures from the rotation pattern with standard deviations of 10.8 and 6.6 km s−1 for the H I and CO line emission, respectively. The mean kinetic energy densities corresponding to these streaming motions are around 0.11 and 0.04 eV/cm3 from either gas tracer. Assuming homogeneity and isotropy in the velocity field, these values are within a factor of a few of the total kinetic energy density. These kinetic energy values are roughly comparable to other energy densities, thus confirming the near-equipartition in the local ISM. Yet, we identify energy and momentum overdensities of around a factor of ten concentrated in the Radcliffe Wave, the Split, and other local density structures. Although we do not find evidence of the local spiral arm’s impact on these energy overdensities, their distribution suggests the influence of large-scale effects that, in addition to supernova feedback, shape the energy distribution and dynamics in the solar neighborhood
Kin-discriminating partner choice promotes the evolution of helping
No full textKin selection theory predicts that individuals should evolve to help relatives, either by helping indiscriminately in a population where they do not move very far from their relatives, or by discriminating kin and conditionally helping them. It has been argued that, because kin discrimination enables individuals to reduce how helpful they are with some social partners as well increase how helpful they are with others, this could lead to an increase or a decrease in the overall level of helping. Specifically, it was argued that kin discrimination would increase the overall level of helping if the function relating the optimal level of help and genetic relatedness is convex, but kin discrimination would decrease the overall level of helping if the function relating the optimal level of help and genetic relatedness is concave. However, this prediction was based on a model in which individuals were not able to choose their social partners but only adjust how helpful they should be toward those social partners they have been allocated. Here, we perform a mathematical analysis showing that being able to choose social partners increases the overall level of helping. Consequently, if kin discriminators are allowed to choose whom they help, kin discrimination is more likely to increase the overall level of helping than previously anticipated. We obtained these results in two complementary theoretical settings: one more general, which makes few demographic assumptions, and the other more specific and concrete, which assumes a patch-structured population with complete dispersal
Descriptions of advanced multimorbidity:a scoping review with content analysis
No full textIntroduction: Multimorbidity is associated with adverse clinical outcomes, including increased symptom burden and healthcare utilisation, particularly towards the end of life. Despite this, there is no accepted method to identify the point at which individuals with deteriorating health due to long-term conditions are nearing the end of life or might benefit from a palliative care approach – conceptualised as ‘Advanced Multimorbidity’. This scoping review explored how Advanced Multimorbidity is described and operationalised within the literature. Methods: Multiple electronic databases and Grey Literature sources were searched following scoping review frameworks. Two reviewers independently performed screening and data extraction. Content analysis was used to examine the different descriptions of Advanced Multimorbidity. Stakeholder consultations were undertaken with clinicians, academics and public participants. Patient and public involvement was separately integrated throughout this review from conceptualisation, design and reporting. Results: Forty-four different descriptions of Advanced Multimorbidity were identified from 38 publications. These varied in terms of the clinical conditions and descriptors used. Eighteen descriptions relied on a single indicator to identify Advanced Multimorbidity; 24 used a multidimensional approach. Stakeholder consultations highlighted the need for descriptions that are user-friendly and actionable. Conclusion: The lack of a standardised definition of Advanced Multimorbidity risks variance in clinical and research practice, potentially affecting patient care. A consensus on defining Advanced Multimorbidity would enable better identification of patients who could benefit from a palliative care approach, ensuring more consistent and person-centred care, as well as supporting research and policy development
A multi-resonant thermally activated delayed fluorescence emitter with a twisted second-generation carbazole dendron showing suppressed concentration quenching and its use in solution-processed organic light-emitting diodes
No full textMulti-resonant thermally activated delayed fluorescence (MR-TADF) emitters have drawn significant interest for use in organic lighting-emitting diodes (OLEDs) as they typically have bright and narrowband emission. However, their rigid, planar structures result in poor solubility in organic solvents and a tendency to aggregate. This usually results in severe aggregation-caused quenching (ACQ), which hinders in particular, their application in solution-processed OLEDs. Herein, a solution-processable MR-TADF emitter 2,7-tBuCzNB has been designed, synthesized and studied. The presence of eight tert-butyl groups and the use of second-generation donor dendrons help enhance its solubility and suppress the ACQ. 2,7-tBuCzNB exhibits narrowband green emission at 493 nm, with a full-width at half maximum of 32 nm and a high photoluminescence quantum yield (ΦPL) of 93% in toluene. The ΦPL values in 1–10 wt% doped films in mCP are slightly lower but still reach up to 80%. Solution-processed OLEDs using this emitter showed maximum external quantum efficiencies (EQEmax) of 11.4 and 10.6% at 5 and 10 wt% doping concentration, respectively. This work demonstrates a strategy to synthesize solution processable MR-TADF emitters for use in solution-processed OLEDs.</div
God as moral anti-examplar in Spinoza
No full textThis paper addresses the question of whether Spinoza subscribes to moral exemplarism, defined as any moral theory including the idea that it is morally good, right, virtuous, praiseworthy, or obligatory to emulate certain figures identified as moral exemplars. The answer is given at multiple levels. At one level, Spinoza endorsed moral exemplarism as a descriptive theory of how we make moral judgements, but does not endorse those judgements. At another level he endorses judgements of good and bad based on conformity to a constructed exemplar of human nature, although the endorsement is perhaps pragmatic rather than moral. At a third level, Spinoza offers as the highest ethical ideal the emulation of God. But since Spinoza’s God is a being devoid of goals and even of any determinate character, emulating it seems to mean rejecting the whole ethical project of trying to find an exemplar to guide one’s moral choices and development
Boron-functionalized graphitic carbon nitride materials for photocatalytic applications:effects on chemical, adsorptive, optoelectronic, and photocatalytic properties
No full textGraphitic carbon nitride (gC3N4, or CN herein) is widely studied as a photocatalyst owing to its ease of synthesis, high stability, and optoelectronic properties. However, its photocatalytic performance often remains limited, and a common approach to tune its function and enhance its performance is by doping. Boron (B) functionalization of CN has showed a potential benefit on photocatalytic performance for several reactions. However, the reason for this improvement and the links between synthesis method, exact B chemical environment, and performance remain unclear. Here, we present a fundamental study that elucidates the influence of (i) B functionalization, (ii) B content, and (iii) choice of B precursor on the physicochemical, adsorptive, optoelectronic, and photocatalytic properties of bulk B-CN. We synthesized two sets of B-CN materials (0.5–11 at% B), using either elemental boron or boric acid as precursors. The samples were characterized using several imaging and spectroscopic techniques, which confirm the integration of B into the material through B–O bonding and the creation of B clusters in the case of the boron precursor, with density functional theory (DFT) calculations supporting our analyses. The distribution of B atoms within B-CN particles remained heterogeneous. Compared to CN, B-functionalized materials show enhanced porosity and CO2 uptake, with similar degrees of light absorption and deeper energy band positions. Transient absorption spectroscopy (TAS) measurements showed that charge carrier populations, lifetimes, and kinetics were not significantly affected by B functionalization; however, at 5 at% B doping, an increase in the concentration of charge carriers was seen. Higher B content enhances the photocatalytic NOx removal under UVA irradiation (almost two-fold) and the selectivity to NO3– from NOx photooxidation, but has no significant effect on CO2 photoreduction, compared to pristine CN. Overall, this study provides fundamental insights to build on and more rationally produce better-performing B-CN photocatalysts
Testing the effectiveness of hybrid infrastructural/nature based sand dune restoration as defence for an urban coastal community in Hong Kong
No full textWe document a hybrid infrastructural/nature based restoration of an artificial backshore dune in Big Wave Bay (Tai Long Wan), a small embayed sandy beach system in Hong Kong. The 2018 Super Typhoon Mangkhut destroyed the dune, believed to have been built by a coastal village community more than 80 years ago and had withstood all intervening storms. The destruction had itself illustrated how extreme events may alter landforms at a catchment scale, and the vulnerabilities of coastal communities that lies within the catchment. Subsequently, the Hong Kong government made a decision to 'hold-the-line' and rebuild defence in-situ, believed to have driven by space constraints, engineering philosophy, and/or public perception. The result may not be the most storm-proof, but it could be seen as the best outcome based on compromises, and could represent the most probable responses towards extreme events in urban coastal communities. Both hard engineering (in the form of concrete footslabs) and nature based approach (in the form of coastal shrub planting) were installed in 2021, and had shown different trajectory of change in the subsequent years. Although the defence mechanisms had not been tested in an extreme event, comparative strengths of the solutions could be surmised by their integration with the natural processes of the beach system. The overall cost effectiveness of this 'hold-the-line' strategy in Big Wave Bay is estimated, using potential land loss from sea level rise fed into a simple socio-economic model to predict potential economic loss. The result could shed light on quantifying the social costs for adaptation strategies in urban coastal communities in response to climate change.
Rationale and ethical assessment of an oropharyngeal gonorrhoea controlled human infection model
No full textInfection with Neisseria gonorrhoeae, the causative agent of gonorrhoea, causes significant morbidity worldwide and can have long-term impacts on reproductive health. The greatest global burden of gonorrhoea occurs in low- and middle-income settings. Global public health significance is increasing due to rising antimicrobial resistance (AMR), which threatens future gonorrhoea management. The oropharynx is an important asymptomatic reservoir for gonorrhoea transmission and a high-risk site for development of AMR and treatment failure. Controlled human infection model (CHIM) studies using N. gonorrhoeae may provide a means to accelerate the development of urgently needed therapeutics, vaccines and other biomedical prevention strategies. A gonorrhoea urethritis CHIM has been used since the 1980s with no reported serious adverse events. Here, we describe the rationale for an oropharyngeal gonorrhoea CHIM, including analysis of potential ethical issues that should inform the development of this novel study design.</p
Self-poled halide perovskite Ruddlesden-Popper ferroelectric-photovoltaic semiconductor thin films and their energy harvesting properties
No full textAmbient energy harvesters with multi-source energy harvesting capabilities are highly desirable for developing compact and sustainable power solutions for emerging technologies such as the Internet of Things. In this study, thin films of low-dimensional halide perovskites, (BA)2(MA)n-1PbnBr3n+1 (n = 1, 2), are demonstrated to be both semiconducting and ferroelectric, enabling the harvesting of mechanical and ambient light energy. By incorporating Cr/Cr2O3 or phenyl-C61-butyric acid methyl ester (PCBM) as a barrier/passivation layer, reproducible ferroelectric properties are consistently achieved in (BA)2(MA)n-1PbnBr3n+1 +1 thin films. The corresponding flexible piezoelectric energy harvesters delivered a peak-to-peak open-circuit voltage of 8 V under a 10 N force, while the photovoltaic devices exhibited an open-circuit voltage of ≈1.2 V under 1 Sun illumination. This study unveils the potential of low-dimensional halide perovskite thin films for lightweight, multi-source energy harvesting and provides key insights into the crucial role of barrier layers in achieving reliable thin-film halide perovskite ferroelectric devices
Higher dose corticosteroids in hospitalised COVID-19 patients requiring ventilatory support (RECOVERY):a randomised, controlled, open-label, platform trial
No full textBackground: Low dose corticosteroids (e.g., 6 mg dexamethasone) have been shown to reduce mortality for hypoxic COVID-19 patients. We have previously reported that higher dose corticosteroids cause harm in patients with clinical hypoxia but not receiving ventilatory support (the combination of non-invasive mechanical ventilation, including high-flow nasal oxygen, continuous positive airway pressure and bilevel positive airway pressure ventilation, and invasive mechanical ventilation or extra-corporeal membrane oxygenation), but the balance of efficacy and safety in patients receiving ventilatory support is uncertain.Methods: This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) assessed multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting adult patients receiving ventilatory support were randomly allocated (1:1) to either usual care with higher dose corticosteroids (dexamethasone 20 mg once daily for 5 days followed by 10 mg once daily for 5 days or until discharge if sooner) or usual standard of care alone (which includes dexamethasone 6 mg once daily for 10 days or until discharge if sooner). The primary outcome was 28-day mortality; secondary outcomes were duration of hospitalisation and (among participants not on invasive mechanical ventilation at baseline) the composite of invasive mechanical ventilation or death. Recruitment closed on 31 March 2024 when funding for the trial ended. The RECOVERY trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936).Findings: Between 25 May 2021 and 9 January 2024, 477 COVID-19 patients receiving ventilatory support were randomly allocated to receive usual care plus higher dose corticosteroids vs. usual care alone (of whom 99% received corticosteroids during the follow-up period). Of those randomised, 221 (46%) were in Asia, 245 (51%) in the UK and 11 (2%) in Africa. 143 (30%) had diabetes mellitus. Overall, 86 (35%) of 246 patients allocated to higher dose corticosteroids vs. 86 (37%) of 231 patients allocated to usual care died within 28 days (rate ratio [RR] 0.87; 95% CI 0.64-1.18; p = 0.37). There was no significant difference in the proportion of patients discharged from hospital alive within 28 days (128 [52%] in the higher dose corticosteroids group vs. 120 [52%] in the usual care group; RR 1.04, 0.81-1.33]; p = 0.78). Among those not on invasive mechanical ventilation at baseline, there was no clear reduction in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (76 [37%] of 206 vs. 93 [45%] of 205; RR 0.79 [95% CI 0.63-1.00]; p = 0.05).Interpretation: In patients hospitalised for COVID-19 receiving ventilatory support, we found no evidence that higher dose corticosteroids reduced the risk of death compared to usual care, which included low dose corticosteroids.<p/