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Statins are the cornerstone treatment for patients with heterozygous familial hypercholesterolaemia but research suggests it could increase the risk of type 2 diabetes in the general population. A low prevalence of type 2 diabetes was reported in some familial hypercholesterolaemia cohorts, raising the question of whether these patients are protected against type 2 diabetes. Obesity is a well known risk factor for the development of type 2 diabetes. We aimed to investigate the associations of known key determinants of type 2 diabetes with its prevalence in people with heterozygous familial hypercholesterolaemia.

To date, it remains challenging to precisely and efficiently construct structurally intriguing polycarbocycles with densely packed stereocenters in organic synthesis. Niduterpenoid B, a naturally occurring ERα inhibitor, exemplifies this complexity with its intricate polycyclic network comprising 5 cyclopentane and 1 cyclopropane rings, featuring 13 contiguous stereocenters, including 4 all-carbon quaternary centers. In this work, we describe the first total synthesis of niduterpenoid B using a structural reorganization strategy. Key features include the following: (1) an efficient methoxy-controlled cascade reaction that precisely forges a highly functionalized tetraquinane (A–D rings) bearing sterically hindered contiguous quaternary stereocenters; (2) a rhodium-catalyzed [1 + 2] cycloaddition that facilitates the construction of a strained 3/5 bicycle (E–F rings) angularly fused with ring D.

Fusing low-resolution (LR) hyperspectral images (HSIs) with high-resolution (HR) multispectral images (MSIs) is a significant technology to enhance the resolution of HSIs. Despite the encouraging results from deep learning (DL) in HSI–MSI fusion, there are still some issues. First, the HSI is a multidimensional signal, and the representability of current DL networks for multidimensional features has not been thoroughly investigated. Second, most DL HSI–MSI fusion networks need HR HSI ground truth for training, but it is often unavailable in reality. In this study, we integrate tensor theory with DL and propose an unsupervised deep tensor network (UDTN) for HSI–MSI fusion. We first propose a tensor filtering layer prototype and further build a coupled tensor filtering module. It jointly represents the LR HSI and HR MSI as several features revealing the principal components of spectral and spatial modes and a sharing code tensor describing the interaction among different modes. Specifically, the features on different modes are represented by the learnable filters of tensor filtering layers, the sharing code tensor is learned by a projection module, in which a co-attention is proposed to encode the LR HSI and HR MSI and then project them onto the sharing code tensor. The coupled tensor filtering module and projection module are jointly trained from the LR HSI and HR MSI in an unsupervised and end-to-end way. The latent HR HSI is inferred with the sharing code tensor, the features on spatial modes of HR MSIs, and the spectral mode of LR HSIs. Experiments on simulated and real remote-sensing datasets demonstrate the effectiveness of the proposed method.

Understanding the lattice evolution of hexanitrostilbene (HNS) is crucial for ensuring its safety and reliability under shock loading. However, the lack of in situ, real-time diagnostics has limited the availability of lattice parameters for shock-loaded explosives. In this study, we utilized dynamic X-ray diffraction technology to obtain the diffraction spectrum of laser shock-loaded HNS and to determine its temporal evolution. Additionally, by improving the laser energy, we initiated HNS and obtained the diffraction spectrum of detonation products during the detonation process. The experimental results showed the presence of a diamond structure in the detonation product, suggesting the existence of either diamond or diamond-like carbon. Our research not only elucidates the crystal structure of shock-loaded HNS and its detonation products but also provides an avenue for laboratory-scale investigations into dynamically loaded explosives, which furnishing an opportunity to unveil the underlying mechanism governing explosive dynamic response behavior.

An asymmetric intramolecular spiro-amination to high steric hindering α-C–H bond of 1,3-dicarbonyl via nitrene transfer using inactive aryl azides has been carried out by developing a novel Cp*Ir(III)-SPDO (spiro-pyrrolidine oxazoline) catalyst, thereby enabling the first successful construction of structurally rigid spiro-quaternary indolinone cores with moderate to high yields and excellent enantioselectivities. DFT computations support the presence of double bridging H–F bonds between [SbF6]−and both the ligand and substrate, which favors the plane-differentiation of the enol π-bond for nitrenoid attacking. These findings open up numerous opportunities for the development of new asymmetric nitrene transfer systems.

The fruits of Rosa roxburghiiTratt. are edible nutritional food with high medicinal value and have been traditionally used as Chinese folk medicine for a long time. In this study, 26 triterpenoids including four new pentacyclic triterpenoids, roxbuterpenes A–D (1, 4, 5, and 24), along with 22 known analogues (2, 3, 6–23, 25, and 26), were isolated from the fruits of R. roxburghii. Their chemical structures were determined on the basis of extensive spectroscopic analyses (including IR, HRESIMS and NMR spectroscopy). The absolute configuration of roxbuterpene A (1) was determined by an X-ray crystallographic analysis. This is the first report of the crystal structure of 5/6/6/6/6-fused system pentacyclic triterpenoid. Notably, roxbuterpenes A and B (1and 4) possessed the A-ring contracted triterpenoid and nortriterpenoid skeletons with a rare 5/6/6/6/6-fused system, respectively. Compounds 1–7, 11, 13–15, 18–20, 24, and 25exhibited moderate or potent inhibitory activities against α-glucosidase. Compounds 2, 4, 6, 11, and 14showed strong activities against α-glucosidase with IC50values of 8.4 ± 1.6, 7.3 ± 2.2, 13.6 ± 1.4, 0.9 ± 0.4, and 12.5 ± 2.4 μM, respectively (positive control acarbose, 10.1 ± 0.8 μM). Compounds 13, 14, and 16moderately inhibited the release of NO (nitric oxide) with IC50values ranging from 25.1 ± 2.0 to 51.4 ± 3.1 μM. Furthermore, the expressions of TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6) were detected by ELISA (enzyme-linked immunosorbent assay), and compounds 13, 14, and 16exhibited moderate inhibitory effects on TNF-α and IL-6 release in a dose-dependent manner ranging from 12.5 to 50 μM.

Glycidic esters represent pivotal constituents in synthetic chemistry, offering enhanced versatility for tailoring toward a diverse array of molecular targets in comparison with simple epoxides. While considerable progress has been made in the asymmetric synthesis of trans- and trisubstituted glycidic esters, achieving enantioselective preparation of cis-glycidic esters has remained a long-standing challenge. Here, we demonstrate a selectivity-predictable modular platform for the asymmetric synthesis of cis-glycidic esters via a novel dinuclear (salen)titanium(III)-catalyzed radical-type kinetic resolution (KR) approach. This radical KR protocol operates under mild conditions and demonstrates a wide substrate scope, facilitating the synthesis of alkyl- and aryl-substituted cis-glycidic esters with high levels of regioselectivity and enantioselectivity, along with hydroxy ester byproducts representing synthetically valuable motifs as well. This study presents a unique exploration of radical-type KR applied to epoxides, effectively overcoming the steric challenges inherent in conventional nucleophilic-type methodologies typically employed in epoxide chemistry.

The synthesis of complex alkanes by the tetrafunctionalization of alkynes is limited and challenging. Herein, an unprecedented efficient geminal diazidation and dibromination of terminal alkynes is developed, which provides novel access to structurally diverse organic azides. The approach has exclusive chemo- and regioselectivity and features mild reaction conditions, good tolerance of various functional groups, and more crucially, no metal involved in the reaction, thereby benefiting the late-stage decoration of medicinal molecules. A mechanistic study showed that the current geminal diazidation and dibromination proceeds via a radical pathway.

Five-carbon (C5) units are the fundamental building blocks that constitute a multitude of natural products. Herein we report an unprecedented unusual C5functionalization of indole regioselectively at the C-2-position enabled by a (2-pyridyl)sulfonyl-directing palladium-catalyzed dehydrogenative strategy with a bulk chemical 2-methyl-2-butene as a C5source. Compared to typical C5functionalization using pentenyl alcohols, carbonates, borates, or halides as the C5source, the protocol not only has a low cost advantage but also is of atom and step economy.

Ammonium ion was introduced to enhance the sulfidization of heterogenite, the main cobalt oxide mineral. The flotation recovery was significantly improved from less than 20% to over 70%. Micro flotation and FT-IR analyses indicated that ammonium ions enhanced the adsorption intensity of xanthate and improved the flotation recovery of heterogenite. Zeta potential, ICP-OES, and XPS tests further illustrated that cobalt on the surface of heterogenite was transferred to the liquid phase by forming ammonia complexes, thereby increasing the sulfur adsorption sites on the mineral surface and promoting sulfidization. This study will contribute to a better understanding of the flotation behavior of heterogenite and provide a valuable reference for the efficient recovery of cobalt oxide ores.

Guaico Culex virus (GCXV) is a newly identified segmented Jingmenvirus from Culexspp. mosquitoes in Central and South America. The genome of GCXV is composed of four or five single-stranded positive RNA segments. However, the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown. In this study, we used reverse genetics to rescue two GCXVs (4S and 5S) that contained four and five RNA segments, respectively, in C6/36 ​cells. Further in vitrocharacterization revealed that the two GCXVs exhibited comparable replication kinetics, protein expression and viral titers. Importantly, GCXV RNAs were detected in the bodies, salivary glands, midguts and ovaries of Culex quinquefasciatusat 4–10 days after oral infection. In addition, two GCXVs can colonize Cx. quinquefasciatuseggs, resulting in positive rates of 15%–35% for the second gonotrophic cycle. In conclusion, our results demonstrated that GCXVs with four or five RNA segments can be detected in Cx. quinquefasciatuseggs during the first and second gonotrophic cycles after oral infection.

Introduction: High-quality epidemiological data on hemorrhagic stroke (HS) and its subtypes, intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH), remains limited in Asian ethnicities. We investigated the trends in HS incidence and 30-day mortality from 2005 to 2019 in a multi-ethnic Asian population from a national registry.Patients and methods: Data on all stroke cases from the Singapore Stroke Registry from 2005 to 2019 were collected. Cases were defined using centrally adjudicated review of diagnosis codes. Death outcomes were obtained by linkage with the national death registry. Incidence (per 100,000 people) and 30-day mortality (per 100 people) were measured as crude and age-standardized rates. Trends were analyzed using linear regression.Results: We analyzed 19,017 cases of HS (83.9% ICH; 16.1% SAH). From 2005 to 2019, age-standardized incidence rates (ASIR) for HS remained stable from 34.4 to 34.5. However, age-standardized mortality rates (ASMR) decreased significantly from 29.5 to 21.4 (p< 0.001). For ICH, ASIR remained stable while ASMR decreased from 30.4 to 21.3 (p< 0.001); for SAH, ASIR increased from 2.7 to 6.0 (p= 0.006) while ASMR remained stable. In subgroup analyses, HS incidence increased significantly in persons <65 years (from 18.1 to 19.6) and Malays (from 39.5 to 49.7).Discussion: From 2005 to 2019, ASIR of HS remained stable while ASMR decreased. Decreasing ASMR reflects improvements in the overall management of HS, consistent with global trends.Conclusion: Population health efforts to address modifiable risk factors for HS in specific demographic subgroups may be warranted to reduce incidence and mortality of HS.

An acid-promoted cyclization of α-azidobenzyl ketones has been developed for the synthesis of 6-substituted quinoline derivatives. A variety of synthetically useful 6-OTf or -OMs quinoline derivatives were obtained in moderate to good yields. The reaction proceeds via C═N bond formation without organophosphine, providing convenient access to structurally interesting and synthetically important 6-substituted quinoline derivatives in moderate to good yields. A mechanistic perspective that is different from the traditional intramolecular Schmidt reaction has been proposed.

Electrocarboxylation of the C(sp3)–O bond in 1,3-oxazolidin-2-ones with CO2to achieve β-amino acids is developed. The C–O bond in substrates can be selectively cleaved via the single electron transfer on the surface of a cathode or through a CO2•–intermediate under additive-free conditions. A great diversity of β-amino acids can be obtained in a moderate to excellent yield and readily converted to various biologically active compounds.

Hyperspectral image (HSI) exhibits high-quality spectral signals that convey subtle differences, enabling the discrimination of similar materials and providing a unique advantage for anomaly detection (AD). Fine spectral of anomalies can be effectively identified amidst heterogeneous background pixels. Given the similarity of materials in spatial and spectral dimensions, joint utilization of spatial and spectral information enhances detection performance. However, many existing AD approaches for HSIs usually achieve high accuracy at the expense of high computational complexity. In response to the requirements of practical detection scenarios-efficiency, robustness, and accuracy-this article introduces a rapid and robust AD algorithm through discriminative band selection for HSIs. We propose a spatial-spectral feature extraction strategy to ensure detection accuracy. Initially, to effectively mine context information across a broad spectral range, the HSI cube in space is partitioned into several groups using a coarse-to-fine strategy. Subsequently, we identify the most relevant and informative bands based on spatial local density and spectral information entropy, forming the coarse HSI bands subset. Following this, we design a multiband target-background ratio (MBTBR) to capture strongly discriminative bands, resulting in the fine HSI bands subset. Finally, we present an adaptively spatial—spectral feature extraction strategy to detect anomalous targets. Extensive experimental results on real hyperspectral datasets demonstrate that the proposed method achieves satisfactory performance compared to the state-of-the-art algorithms, validating its strong robustness and low computational complexity simultaneously.

Research on multiview stereo (MVS) based on remote sensing images has promoted the development of large-scale urban 3-D reconstruction. However, remote sensing multiview image data suffer from the problems of occlusion and uneven brightness between views during acquisition, which leads to the problem of blurred details in depth estimation. To solve the above problem, we reexamine the deformable learning method in the MVS task and propose a novel paradigm based on view space and depth deformable learning (SDL-MVS), aiming to learn deformable interactions of features in different view spaces and deformably model the depth ranges and intervals to enable high accurate depth estimation. Specifically, to solve the problem of view noise caused by occlusion and uneven brightness, we propose a progressive space deformable sampling (PSS) mechanism, which performs deformable learning of sampling points in the 3-D frustum space and the 2-D image space in a progressive manner to embed source features to the reference feature adaptively. To further optimize the depth, we introduce depth hypothesis deformable discretization (DHD), which achieves precise positioning of the depth prior by adaptively adjusting the depth range hypothesis and performing deformable discretization of the depth interval hypothesis. Finally, our SDL-MVS achieves explicit modeling of occlusion and uneven brightness faced in MVS through the deformable learning paradigm of view space and depth, achieving accurate multiview depth estimation. Extensive experiments on LuoJia-MVS and WHU datasets show that our SDL-MVS reaches state-of-the-art performance. It is worth noting that our SDL-MVS achieves a mean absolute error (MAE) error of 0.086 and an accuracy of 98.9% for Acc $_{\lt 0.6\,\text {m}}$ and 98.9% for Acc $_{\lt 3-\text {interval}}$ on the LuoJia-MVS dataset under the premise of three views as input.

Herein, the de novosynthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline (SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

According to the requirements of Chang’e 4 mission, the configuration and layout of Queqiao relay satellite are designed based on the mission analysis. The satellite’s shape, structure size, mechanical interface of launch vehicle adapter, module division, primary structure and equipment layout are determined. Based on small satellite’s platform and main structure, we optimized configuration and layout of structure size, solar array fixing, tank fixing, big antenna fixing. Combining with light-weighting technology and 3D printing technology, achieving a goal of zero-counterweight, the loading ratio reaches a high level of advanced small satellite. To pursue the tenet of “Simplicity, symmetry, and harmony”, the design ability is highlighted by combining the functionality and simplicity. It provides the reference to the similar satellite configuration and layout.

In this letter, an efficient two-stage adaptive beamforming algorithm is proposed for sparse linear array synthesis. In the first stage, the unitary matrix pencil method is employed to synthesize a sparse linear array to generate a pattern with a low sidelobe level (SLL). Next, by serving the results obtained previously as a constraint, an adaptive beamforming method is implemented to enhance the anti-interference ability of the array while maintaining the shape of sparse patterns as much as possible. Moreover, an adjustable factor is introduced to enhance the capability of seeking feasible solutions, and new constraints are raised to broad nulls, respectively. Four numerical examples involving low SLL, single interferer, multiple interferers and broad nulls are provided to validate the flexibility and effectiveness of the proposed method. Simulation results show the superior anti-interference performance and high computational efficiency of the proposed algorithm.

Due to the range-angle-dependent beampattern, frequency diverse array (FDA) has attracted extensive attention. However, the inherent time-varying and range-angle coupling problems of the FDA are still troublesome. In this article, a quasi-time-invariant focusing beamforming scheme for retrodirective (RD)-FDA is proposed to alleviate the above tough problems. Specifically, linear and semicircular RD-FDAs are explored to achieve automatic beam alignment of the desired target without phase weights. By establishing an artificial neural network (ANN) framework, frequency offsets can be optimized to match the radiation requirements. By minimizing the loss value of the network, the desired focusing pattern can be realized. Then, optimized frequency offsets are periodically inverted to limit the signal phase, which allows flexible control of the spatial variation range of the mainlobe beam. Simulation results show the effectiveness and superiority of the proposed scheme to achieve quasi-time-invariant beamforming.

A catalytic enantioselective polycyclization of tertiary enamides with terminal silyl enol ethers has been developed by virtue of Cu(OTf)2catalysis with a novel spiropyrroline-derived oxazole (SPDO) ligand. This tandem reaction offers an effective approach to assemble bicyclic and tricyclic N-heterocycles bearing both aza- and oxa-quaternary stereogenic centers, which are primal subunits in a range of natural alkaloids. Strategic application of this methodology and a late-stage radical cyclization as key steps have been showcased in the concise total synthesis of (−)-cephalocyclidin A.