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Covalent organic frameworks (COFs) are a promising class of metal-free catalysts, offering a high structural and functional variety. Here, we systematically study imine-linked COFs with donor (D) and acceptor (A) groups using density functional theory (DFT). Using water splitting as a model reaction, we analyze the effects of protonation of the catalyst, the orientation of the imine linkage leading to different constitutional isomers, and solvation. In agreement with experimental results, we show that protonation decreases the band gap. In addition, COFs in which the donor is closer to the nitrogen atom of the imine group (DNCA) have lower band gaps than those in which the donor is closer to the carbon atom (DCNA). Three different D/A COFs are compared in this work, for which energies for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) and corresponding electrochemical overpotentials are computed. We show that reaction energies are very similar for DCNA and DNCA COFs. The differences in hydrogen evolution rates between the constitutional isomers observed experimentally in (photocatalytic) HER (Yang et al., Nat. Commun., 2022, 13, 6317), are proposed to be at least in part a consequence of differences in charge distribution. [ABSTRACT FROM AUTHOR]

Majorization is a fundamental model of uncertainty with several applications in areas ranging from thermodynamics to entanglement theory, and constitutes one of the pillars of the resource-theoretic approach to physics. Here, we improve on its relation to measurement apparatuses. In particular, after discussing what the proper notion of second law in this scenario is, we show that, for a sufficiently large state space, any family of entropy-like functions constituting a second law must be countably infinite. Moreover, we provide an analogous result for a variation of majorization known as thermo-majorization which, in fact, does not require any constraint on the state space provided the equilibrium distribution is not uniform. Finally, we discuss the applicability of our results to molecular diffusion and catalytic majorization. In this regard, we consider a variation of majorization used in plasma physics as a model of molecular diffusion and show that no finite family of entropy-like functions constituting a second law of molecular diffusion exists. Moreover, we show how our results are useful when dealing with a conjecture regarding catalytic majorization (i.e. trumping). In particular, we show that the sort of characterizations of trumping that have been considered before require an infinite family of real-valued functions. [ABSTRACT FROM AUTHOR]

The review of Dan Cui's book "Identity and Belonging among Chinese Canadian Youth" examines the formation of identity among Chinese-Canadian adolescents in the areas of school, family, and media. It delves into the historical discrimination faced by Chinese immigrants in the 19th and 20th centuries and how this has influenced the current perception and treatment of Chinese-Canadian youth. The book also sheds light on the effects of school discrimination and the challenges faced by the second generation of Chinese Canadians in forming their identities. It emphasizes how Canada's multicultural policy promotes the assimilation of minorities and highlights the importance of language for the ethnic identity of young Chinese individuals in Canada. [Extracted from the article]

Several guidelines do not recommend beta-blocker as the first-line treatment for hypertension because of its inferior efficacy in stroke prevention. Combination therapy with beta-blocker is commonly used for blood pressure control. We compared the clinical outcomes in patients treated with amlodipine plus bisoprolol (A + B), a ß1-selective beta-blocker and amlodipine plus valsartan (A + V). A population-based cohort study was performed using data from the Taiwan National Health Insurance Research Database. From 2012 to 2019, newly diagnosed adult hypertensive patients who received initial amlodipine monotherapy and then switched to A + V or A + B were included. The efficacy outcomes included all-cause death, atherosclerotic cardiovascular disease (ASCVD) event (cardiovascular death, myocardial infarction, ischemic stroke, and coronary revascularization), hemorrhagic stroke, and heart failure. Multivariable Cox proportional hazards model was used to evaluate the relationship between outcomes and different treatments. Overall, 4311 patients in A + B group and 10980 patients in A + V group were included. After a mean follow-up of 4.34 ± 1.79 years, the efficacy outcomes were similar between the A + V and A + B groups regarding all-cause death (adjusted hazard ratio [aHR] 0.99, 95% confidence interval [CI] 0.83–1.18), ASCVD event (aHR 0.97, 95% CI 0.84–1.12), and heart failure (aHR 1.06, 95% CI 0.87–1.30). The risk of hemorrhagic stroke was lower in A + B group (aHR 0.70, 95% CI 0.52–0.94). The result was similar when taking death into consideration in competing risk analysis. The safety outcomes were similar between the 2 groups. There was no difference of all-cause death, ASCVD event, and heart failure in A + B vs. A + V users. But A + B users had a lower risk of hemorrhagic stroke. [ABSTRACT FROM AUTHOR]

Geodesign is a participatory research and planning process that manages diverse boundaries and combines place-based local knowledge and values, design and planning expertise, and geographic information science for the purpose of collaborative and well-informed spatial planning. It is particularly effective in managing boundaries between stakeholders, knowledge frameworks, and technology· Geodesign is valuable in the early stages of planning, facilitating problem characterization and citizen involvement, as well as impact assessment. [ABSTRACT FROM AUTHOR]

Purpose: Histological microvascular invasion (MVI) is a risk factor for poor survival and early recurrence in hepatocellular carcinoma (HCC) after surgery. Its prognostic value in the setting of locoregional therapies (LRT), where no tissue samples are obtained, remains unknown. This study aims to establish CT-derived indices indicative of MVI on liver MRI with superior soft tissue contrast and evaluate their association with patient survival after ablation via interstitial brachytherapy (iBT) versus iBT combined with prior conventional transarterial chemoembolization (cTACE). Patients and Methods: Ninety-five consecutive patients, who underwent ablation via iBT alone (n = 47) or combined with cTACE (n = 48), were retrospectively included between 01/2016 and 12/2017. All patients received contrast-enhanced MRI prior to LRT. Overall (OS), progression-free survival (PFS), and time-to-progression (TTP) were assessed. Decision-tree models to determine Radiogenomic Venous Invasion (RVI) and Two-Trait Predictor of Venous Invasion (TTPVI) on baseline MRI were established, validated on an external test set (TCGA-LIHC), and applied in the study cohorts to investigate their prognostic value for patient survival. Statistics included Fisher's exact and t-test, Kaplan–Meier and cox-regression analysis, area under the receiver operating characteristic curve (AUC-ROC) and Pearson's correlation. Results: OS, PFS, and TTP were similar in both treatment groups. In the external dataset, RVI showed low sensitivity but relatively high specificity (AUC-ROC = 0.53), and TTPVI high sensitivity but only low specificity (AUC-ROC = 0.61) for histological MVI. In patients following iBT alone, positive RVI and TTPVI traits were associated with poorer OS (RVI: p < 0.01; TTPVI: p = 0.08), PFS (p = 0.04; p = 0.04), and TTP (p = 0.14; p = 0.03), respectively. However, when patients with combined cTACE and iBT were stratified by RVI or TTPVI, no differences in OS (p = 0.75; p = 0.55), PFS (p = 0.70; p = 0.43), or TTP (p = 0.33; p = 0.27) were observed. Conclusion: The study underscores the role of non-invasive imaging biomarkers indicative of MVI to identify patients, who would potentially benefit from embolotherapy via cTACE prior to ablation rather than ablation alone. [ABSTRACT FROM AUTHOR]

In response to the pressing challenges of the ongoing biodiversity crisis, the protection of endangered species and their habitats, as well as the monitoring of invasive species are crucial. Habitat suitability modeling (HSM) is often treated as the silver bullet to address these challenges, commonly relying on generic variables sourced from widely available datasets. However, for species with high habitat requirements, or for modeling the suitability of habitats within the geographic range of a species, variables at a coarse level of detail may fall short. Consequently, there is potential value in considering the incorporation of more targeted data, which may extend beyond readily available land cover and climate datasets. In this study, we investigate the impact of incorporating targeted land cover variables (specifically tree species composition) and vertical structure information (derived from LiDAR data) on HSM outcomes for three forest specialist bat species (Barbastella barbastellus, Myotis bechsteinii, and Plecotus auritus) in Rhineland‐Palatinate, Germany, compared to commonly utilized environmental variables, such as generic land‐cover classifications (e.g., Corine Land Cover) and climate variables (e.g., Bioclim). The integration of targeted variables enhanced the performance of habitat suitability models for all three bat species. Furthermore, our results showed a high difference in the distribution maps that resulted from using different levels of detail in environmental variables. This underscores the importance of making the effort to generate the appropriate variables, rather than simply relying on commonly used ones, and the necessity of exercising caution when using habitat models as a tool to inform conservation strategies and spatial planning efforts. [ABSTRACT FROM AUTHOR]

Squamous cell carcinoma (SCC) is the second most common skin cancer worldwide, and exposure to ultraviolet (UV) light is a major cause of SCC. UV nail lamps can be used for drying and hardening acrylic or gel nail polish. We report a case of a 52-year-old Caucasian woman with an 18-year history of UV nail lamp use every 3 weeks and an 18-year history of weekly tanning bed use who presented with over 25 actinic keratoses and two SCC in situ on her dorsal hands. Of note, this patient has never had any previous biopsies, skin cancer or precancers, or skin cancer or precancer treatment at any time in the past and on skin examination had no precancers or cancers elsewhere on her body. We also review the existing research regarding nail lamp use, which overall suggests that the risk of carcinogenesis is low, and discuss ways dermatologists can educate patients regarding proper UV nail lamp use to minimize risks. This patient’s extensive UV nail lamp use coupled with UVA exposure from tanning beds may have put her at particular risk and exacerbated the effects of the nail lamp alone.

We present a Lagrangian convective transport scheme developed for global chemistry and transport models, which considers the variable residence time that an air parcel spends in convection. This is particularly important for accurately simulating the tropospheric chemistry of short-lived species, e.g., for determining the time available for heterogeneous chemical processes on the surface of cloud droplets. In current Lagrangian convective transport schemes air parcels are stochastically redistributed within a fixed time step according to estimated probabilities for convective entrainment as well as the altitude of detrainment. We introduce a new scheme that extends this approach by modeling the variable time that an air parcel spends in convection by estimating vertical updraft velocities. Vertical updraft velocities are obtained by combining convective mass fluxes from meteorological analysis data with a parameterization of convective area fraction profiles. We implement two different parameterizations: a parameterization using an observed constant convective area fraction profile and a parameterization that uses randomly drawn profiles to allow for variability. Our scheme is driven by convective mass fluxes and detrainment rates that originate from an external convective parameterization, which can be obtained from meteorological analysis data or from general circulation models. We study the effect of allowing for a variable time that an air parcel spends in convection by performing simulations in which our scheme is implemented into the trajectory module of the ATLAS chemistry and transport model and is driven by the ECMWF ERA-Interim reanalysis data. In particular, we show that the redistribution of air parcels in our scheme conserves the vertical mass distribution and that the scheme is able to reproduce the convective mass fluxes and detrainment rates of ERA-Interim. We further show that the estimated vertical updraft velocities of our scheme are able to reproduce wind profiler measurements performed in Darwin, Australia, for velocities larger than 0.6 m s−1. SO2 is used as an example to show that there is a significant effect on species mixing ratios when modeling the time spent in convective updrafts compared to a redistribution of air parcels in a fixed time step. Furthermore, we perform long-time global trajectory simulations of radon-222 and compare with aircraft measurements of radon activity.

Identifying reaction pathways is a major challenge in chemistry, and proves particularly difficult for surface reactions. Here the authors show that imaging the molecular orbitals with photoemission tomography provides insight into the structure of surface intermediates allowing their identification.

The paper focuses on the Value at Risk model, which is nowadays often used for risk analysis mostly in the banking and insurance industries. Following the characteristics of the model principle, the Value at Risk is interpreted in the economic sense. Two sub-methods are mentioned: Monte Carlo method and historical simulation method. Author presents a number of empirical studies focused on the application of these methods in the practice. The aim of the paper is to apply the Value at Risk model to selected stocks from the SPAD segment of the Prague Stock Exchange within the 2011 period using these two sub-methods. The confidence interval, hold period and other important parameters related to the sub-methods are selected. Based on historical stock prices, various statistical indicators are calculated. Non-diversified and diversified Value at Risk, calculated by the sub-methods are compared. The individual differences among relative, absolute and marginal Value at Risk are described in the paper. Author presents possibility of reducing the Value at Risk.

We define common thermodynamic concepts purely within the framework of general Markov chains and derive Jarzynski’s equality and Crooks’ fluctuation theorem in this setup. In particular, we regard the discrete-time case, which leads to an asymmetry in the definition of work that appears in the usual formulation of Crooks’ fluctuation theorem. We show how this asymmetry can be avoided with an additional condition regarding the energy protocol. The general formulation in terms of Markov chains allows transferring the results to other application areas outside of physics. Here, we discuss how this framework can be applied in the context of decision-making. This involves the definition of the relevant quantities, the assumptions that need to be made for the different fluctuation theorems to hold, as well as the consideration of discrete trajectories instead of the continuous trajectories, which are relevant in physics.

Magnetic resonance imaging (MRI) can potentially be used for non-invasive screening of patients with stable angina pectoris to identify probable obstructive coronary artery disease. MRI-based coronary blood flow quantification has to date only been performed in a 2D fashion, limiting its clinical applicability. In this study, we propose a framework for coronary blood flow quantification using accelerated 4D flow MRI with respiratory motion correction and compressed sensing image reconstruction. We investigate its feasibility and repeatability in healthy subjects at rest. Fourteen healthy subjects received 8 times-accelerated 4D flow MRI covering the left coronary artery (LCA) with an isotropic spatial resolution of 1.0 mm3. Respiratory motion correction was performed based on 1) lung-liver navigator signal, 2) real-time monitoring of foot-head motion of the liver and LCA by a separate acquisition, and 3) rigid image registration to correct for anterior-posterior motion. Time-averaged diastolic LCA flow was determined, as well as time-averaged diastolic maximal velocity (VMAX) and diastolic peak velocity (VPEAK). 2D flow MRI scans of the LCA were acquired for reference. Scan-rescan repeatability and agreement between 4D flow MRI and 2D flow MRI were assessed in terms of concordance correlation coefficient (CCC) and coefficient of variation (CV). The protocol resulted in good visibility of the LCA in 11 out of 14 subjects (six female, five male, aged 28 ± 4 years). The other 3 subjects were excluded from analysis. Time-averaged diastolic LCA flow measured by 4D flow MRI was 1.30 ± 0.39 ml/s and demonstrated good scan-rescan repeatability (CCC/CV = 0.79/20.4%). Time-averaged diastolic VMAX (17.2 ± 3.0 cm/s) and diastolic VPEAK (24.4 ± 6.5 cm/s) demonstrated moderate repeatability (CCC/CV = 0.52/19.0% and 0.68/23.0%, respectively). 4D flow- and 2D flow-based diastolic LCA flow agreed well (CCC/CV = 0.75/20.1%). Agreement between 4D flow MRI and 2D flow MRI was moderate for both diastolic VMAX and VPEAK (CCC/CV = 0.68/20.3% and 0.53/27.0%, respectively). In conclusion, the proposed framework of accelerated 4D flow MRI equipped with respiratory motion correction and compressed sensing image reconstruction enables repeatable diastolic LCA flow quantification that agrees well with 2D flow MRI.