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Aims: To validate cardiovascular risk prediction models for individuals with diabetes using the UK Biobank in order to assess their applicability. Methods: We externally validated 19 cardiovascular risk scores from seven risk prediction models (Chang et al., Framingham, University of Hong Kong‐Singapore [HKU‐SG], Li et al, RECODe [risk equations for complications of type 2 diabetes], SCORE [Systematic Coronary Risk Evaluation] and the UK Prospective Diabetes Study Outcomes Model 2 [UKPDS OM2]), identified from systematic reviews, using UK Biobank data from 2006 to 2021 (n = 23 685; participant age 40–71 years, 63.5% male). We evaluated performance by assessing the discrimination and calibration of the models for the endpoints of mortality, cardiovascular mortality, congestive heart failure, myocardial infarction, stroke, and ischaemic heart disease. Results: Over a total of 269 430 person‐years of follow‐up (median 11.89 years), the models showed low‐to‐moderate discrimination performance on external validation (concordance indices [c‐indices] 0.50–0.71). Most models had low calibration with overprediction of the observed risk. RECODe outperformed other models across four comparable endpoints for discrimination: all‐cause mortality (c‐index 0.67, 95% confidence interval [CI] 0.65–0.69), congestive heart failure (c‐index 0.71, 95% CI 0.69–0.72), myocardial infarction (c‐index 0.67, 95% CI 0.65–0.68); and stroke (c‐index 0.65, 95% CI 0.62–0.68), and for calibration (except for all‐cause mortality). The UKPDS OM2 had comparable performance to RECODe for all‐cause mortality (c‐index 0.67, 95% CI 0.66–0.69) and cardiovascular mortality (c‐index 0.71, 95% CI 0.70–0.73), but worse performance for other outcomes. The models performed better for younger participants and somewhat better for non‐White ethnicities. Models developed from non‐Western datasets showed worse performance in our UK‐based validation set. Conclusions: The RECODe model led to better risk estimations in this predominantly White European population. Further validation is needed in non‐Western populations to assess generalizability to other populations. [ABSTRACT FROM AUTHOR]

Magnetic refrigeration technology based on the magnetocaloric effect (MCE) of magnetic substances has been considered a prominent, energy‐efficient, and environmentally benign cooling method. Exploring suitable magnetic substances is a prerequisite for practical applications. A family of rare‐earth‐free magnetocaloric materials called Mn30Fe20−xCuxAl50 alloys is identified room‐temperature refrigeration, which are derived from the well‐known MnAl‐based permanent magnets. As expected from experimental and theoretical investigations, all of the Mn30Fe20−xCuxAl50 alloys are crystallized in a stable cubic CsCl‐type crystal structure, revealing a single second‐order type magnetic phase transition (MPT) with tunable MPT temperature. They also exhibit a large reversible MCE and good magnetocaloric performances in a wide temperature range. Crucially, these Mn30Fe20−xCuxAl50 alloys represent a rare case of magnetic materials belonging to a large family that can be fabricated from low‐price, earth‐abundant, and non‐toxic elements. They could provide new choices for practical room‐temperature magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

RGA5 is a component of the Pia resistance‐protein pair (RGA4/RGA5) from Oryza sativa L. japonica. It acts as an immune receptor that directly recognizes the effector AVR1‐CO39 from Magnaporthe oryzae via a C‐terminal non‐LRR domain (RGA5A_S). The interaction between RGA5A_S and AVR1‐CO39 relieves the repression of RGA4, leading to effector‐independent cell death. To determine the structure of the complex of RGA5A_S and AVR1‐CO39 and to understand the details of this interaction, the complex was prepared by fusing the proteins together, by mixing them in vitro or by co‐expressing them in one host cell. Samples purified via the first two strategies were crystallized under two different conditions. A mixture of AVR1‐CO39 and RGA5A_S (complex I) crystallized in 1.1 M ammonium tartrate dibasic, 0.1 M sodium acetate–HCl pH 4.6, while crystals of the fusion complex RGA5A_S‐TEV‐AVR1‐CO39 (complex II) were grown in 2 M NaCl. The crystal of complex I belonged to space group P3121, with unit‐cell parameters a = b = 66.2, c = 108.8 Å, α = β = 90, γ = 120°. The crystals diffracted to a Bragg spacing of 2.4 Å, and one molecule each of RGA5A_S and AVR1‐CO39 were present in the asymmetric unit of the initial model. The crystal of complex II belonged to space group I4, with unit‐cell parameters a = b = 137.4, c = 66.2 Å, α = β = γ = 90°. The crystals diffracted to a Bragg spacing of 2.72 Å, and there were two molecules of RGA5A_S and two molecules of AVR1‐CO39 in the asymmetric unit of the initial model. Further structural characterization of the interaction between RGA5A_S and AVR1‐CO39 will lead to a better understanding of the mechanism underlying effector recognition by R proteins. [ABSTRACT FROM AUTHOR]

With PhI as catalyst and mCPBA as oxidant, a novel and efficient catalytic procedure has been developed for the acetoxyselenylation and formyloxyselenylation of alkenes. In this protocol, PhI is first oxidized into hypervalent iodine intermediate, which promotes the cleavage of Se-Se bond in diselenides. The in situ generated electrophilic selenium species then reacts with alkenes, affording 2-acetoxy-1-selenides and 2-formyloxy-1-selenides in high regioselectivity and good yields. [ABSTRACT FROM AUTHOR]

In the presence of NH4I as catalyst and m-chloroperbenzoic acid as oxidant, the Se-Se bond cleavage of diselenides undergoes smoothly. The in situ generated reactive electrophilic Se species reacts with alkenes quickly, and a series of β-hydroxy selenides are prepared in good yields. This new catalytic method for synthesis of β-hydroxy selenides is a stereospecific anti addition, which occurs with a Markovnikov orientation. [ABSTRACT FROM AUTHOR]

A simple, multiple‐hydrogen‐bond approach to fabricating physically crosslinked, Amylopectin reinforced polyacrylamide/poly(vinyl alcohol) (Amy/PAAm/PVA) double‐network (DN) hydrogels with super toughness in bulk and at solid interfaces is reported. The Amy/PAAm/PVA DN hydrogels exhibit high tensile strength (854.1 kPa), high extensibility (≈eight times), high bulk toughness (4094.8 kJ m−3), good self‐recovery property (≈92% of self‐recovery at room temperature), and strong adhesion to nonporous glass surfaces (≈158 kPa). Such tough and adhesive DN hydrogels have great potential for various applications in engineering artificial soft tissues, flexible electronics, and wearable devices. [ABSTRACT FROM AUTHOR]

Advantages of the new method are mild reaction conditions, simple procedure, and good yields. [ABSTRACT FROM AUTHOR]

The in-situ generated reactive electrophilic Se species reacts with several alkenes (I) furnishing β-hydroxy selenides in moderate to good yields. [ABSTRACT FROM AUTHOR]

Advantages of the new method are mild reaction conditions, simple procedure, and good yields. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to present an end‐to‐end deep convolutional neural network to improve the dual‐energy CT (DECT) material decomposition performance. Methods: In this study, we proposes a unified mutual‐domain (sinogram domain and CT domain) material decomposition network (DIRECT‐Net) for DECT imaging. By design, the DIRECT‐Net has immediate access to mutual‐domain data, and utilizes stacked convolution neural network layers for noise reduction and material decomposition. The training data are numerically generated following the fundamental DECT imaging physics. Numerical simulation of the XCAT digital phantom, experiments of a biological specimen, a calcium chloride phantom and an iodine solution phantom are carried out to evaluate the performance of DIRECT‐Net. Comparisons are performed with different DECT decomposition algorithms. Results: Results demonstrate that the proposed DIRECT‐Net can generate water and bone basis images with less artifacts compared to the other decomposition methods. Additionally, the quantification errors of the calcium chloride (75‐375 mg/cm3) and the iodine (2‐20 mg/cm3) are less than 4%. Conclusions: An end‐to‐end material decomposition network is proposed for quantitative DECT imaging. The qualitative and quantitative results demonstrate that this new DIRECT‐Net has promising benefits in improving the DECT image quality. [ABSTRACT FROM AUTHOR]

Conditions in space, such as microgravity, may affect the hematopoietic and bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) of astronauts. However, to date, few detailed phenotype change data about the different type of hematopoietic cells have reported. In this study, C57BL/6 mice were randomly divided into two groups: a control group (control) and a hindlimb suspension group (treated). After four weeks of hindlimb suspension, we found that this simulated microgravity (sµg) condition could increase the percentage of monocytes and macrophages and decrease the percentage of B lymphocytes and mature red cells in bone marrow. The percentage of B lymphocytes in the spleen and the red blood cell count in peripheral blood also decreased, consistent with the response of bone marrow. The cytoskeleton in the BM‐MSCs was disrupted. The expression levels of hematopoietic‐related genes, such as fms‐like tyrosine kinase‐3 ligand, granulocyte‐macrophage colony stimulating factor, interleukin‐3, and adipogenic differentiation associated genes, leptin and proliferator‐activated receptor γ type 2, were upregulated under sµg conditions. These results indicated that simulating microgravity can affect the phenotype of certain types of hematopoietic cells and the morphology and gene expression pattern of BM‐MSCs. [ABSTRACT FROM AUTHOR]

The research on multiple hydrogen bonds (H‐bonds) hydrogels have gradually aroused wide interest. In this paper, a multiple H‐bonds‐reinforced poly(acrylamide‐co‐2‐vinyl‐4,6‐diamino‐2‐vinyl‐1,3,5‐triazine)/tannic acid (P(Am‐co‐VDT)/TA) hydrogels are prepared. The results suggest that the prepared hydrogel has two types of H‐bonds crosslinking regions: A "soft" region of H‐bonds between the diaminotriazine (DAT) moieties on the polymer chains and the TA pyrogallol/catechol groups, and a "hard" region of H‐bonds forming by DAT moieties with itself. The hard crosslinking region exhibits significantly higher activation energy than the soft region. Such soft and hard dual physically crosslinked networks dramatically enhance the mechanical properties of P(Am‐co‐VDT)/TA hydrogels in a synergistic manner (tensile strength is 2.34 MPa, elongation at break is 410%). Due to the multiple hydrogen bonds, the hydrogel has good pH sensitivity and rapid response to shape memory within a few minutes. In addition, the hydrogels have the capacity of physical adsorption of the anti‐inflammatory drug diclofenac sodium and other molecules with a specific spatially arranged chemical composition. These hydrogels with high mechanical strength, excellent shape memory behavior, and capacity of adsorption of anti‐inflammatory drug could be attractive candidates for applications in the fields of biomedicine, tissue engineering, and medical materials. [ABSTRACT FROM AUTHOR]