Visible light-induced cascade annulation of sulfoxonium ylides with azides for the synthesis of 2-trifluoromethyl indoles.

An efficient protocol was reported for the synthesis of 2-trifluoromethyl indoles through visible-light-promoted intermolecular cyclization of sulfoxonium ylides with azides, without the need for external photocatalysts, transition metals, or bases. The formation of 2-trifluoromethyl indoles involves an intriguing cascade process including azide rearrangement, intermolecular nucleophilic addition, and visible-light-promoted cyclization of a key intermediate. The protocol features high efficiency, mild conditions, excellent substrate compatibility and good regioselectivity.

Nanoscale covalent organic framework-mediated pyroelectrocatalytic activation of immunogenic cell death for potent immunotherapy.

The conventional molecular immunogenic cell death (ICD) inducers suffer from poor biocompatibility and unsatisfactory efficacy. Here, a biocompatible nanosized covalent organic framework (nCOF)-based pyroelectric catalyst (denoted as TPAD-COF NPs) is designed for pyroelectric catalysis-activated in situ immunotherapy. TPAD-COF NPs confine organic pyroelectric molecules to rigid TPAD-COF NPs to substantially reduce aggregation and enhance biocompatibility, thus improving pyroelectrocatalytic efficiency.

Catalyst-Free [4+1] Annulation of α-Imidoyl Sulfoxonium Ylides and Diazo Compounds Enabling the Modular Synthesis of 2-Indanones and 3(2)-Furanones.

A novel substrate-regulated [4+1] annulation of α-imidoyl sulfoxonium ylides with diazoketones under catalyst-free conditions is described. The reaction proceeds through a coupling of sulfoxonium ylides and in situ-generated ketenes to form the key reactive zwitterionic intermediates, followed by selective formation of C-C or C-O bonds to achieve five-membered ring systems. The cascade reaction permits the direct synthesis of synthetically useful 2-indanones and 3(2)-furanones, which expands the reaction pattern of sulfoxonium ylides in annulation transformation.

Insights into the molecular network characteristics of major HIV-1 subtypes in developed Eastern China: a study based on comprehensive molecular surveillance data.

Purpose: This study aimed to conduct a comprehensive molecular epidemiology study of major HIV-1 subtypes in developed Eastern China (Zhejiang Province).

Methods: Plasma samples and epidemiological information were collected from 4180 newly diagnosed HIV-1 positive patients in Zhejiang Province in 2021. Pol sequences were obtained to determine the subtypes via multiple analytical tools.

The evolutionary and transmission dynamics of HIV-1 CRF08_BC.

HIV-1 CRF08_BC is a significant subtype in China, though its origin and spread remain incompletely understood. Previous studies using partial genomic data have provided insights but lack comprehensive analysis. Here, we investigate the early evolutionary and spatiotemporal dynamics of HIV-1 CRF08_BC in China and Myanmar using near-complete genome sequences.

Detection of Cervical Lesion Cell/Clumps Based on Adaptive Feature Extraction.

Automated detection of cervical lesion cell/clumps in cervical cytological images is essential for computer-aided diagnosis. In this task, the shape and size of the lesion cell/clumps appeared to vary considerably, reducing the detection performance of cervical lesion cell/clumps. To address the issue, we propose an adaptive feature extraction network for cervical lesion cell/clumps detection, called AFE-Net.

Engineering an Organic Nanoplatform for Augmented Pyroeletroimmunotherapy.

Photothermal immunotherapy has shown great promise in the treatment of tumor metastasis. However, the thermal resistance of tumor cells substantially compromises the treatment effect of photothermal immunotherapy. Herein, a high-performance organic pyroelectric nanoplatform, Bu-TPAD-BF nanoparticles (NPs), is rationally engineered for the effective pyroelectroimmunotherapy of tumor metastasis.

The emergence and circulation of human immunodeficiency virus (HIV)-1 subtype C.

Human immunodeficiency virus (HIV)-1 subtype C is the most prevalent globally and is thought to have originated in non-human primates in the Democratic Republic of Congo. Although the global dominance of HIV-1 subtype C is well established, a thorough understanding of its evolutionary history and transmission dynamics across various risk populations remains elusive. The current knowledge is insufficient to fully capture the global diversification and dissemination of this subtype.

Enantioselective synthesis of spiro-,-ketals iridium and Brønsted acid co-catalyzed asymmetric formal [4+2] cycloaddition.

We present an iridium and Brønsted acid co-catalyzed enantioselective formal [4+2] cycloaddition reaction of cyclic enamides with 2-(1-hydroxyallyl)phenols. This method yields a wide range of -unsubstituted spiro-,-ketals, with good efficiency (up to 94%) and excellent enantioselectivities (most >95% ee). The protocol features easy scale-up and facile product derivatization.

Optimizing ancestral trait reconstruction of large HIV Subtype C datasets through multiple-trait subsampling.

Large datasets along with sampling bias represent a challenge for phylodynamic reconstructions, particularly when the study data are obtained from various heterogeneous sources and/or through convenience sampling. In this study, we evaluate the presence of unbalanced sampled distribution by collection date, location, and risk group of human immunodeficiency virus Type 1 Subtype C using a comprehensive subsampling strategy and assess their impact on the reconstruction of the viral spatial and risk group dynamics using phylogenetic comparative methods. Our study shows that a most suitable dataset for ancestral trait reconstruction can be obtained through subsampling by all available traits, particularly using multigene datasets.

Formal (4+2) cycloaddition of azoalkenes with trifluoromethylimidoyl sulfoxonium ylides: synthesis of trifluoromethyl pyridazine derivatives.

CF-substituted imidoyl sulfoxonium ylides (TFISYs) are extraordinarily versatile and powerful synthons for use in cyclization chemistry that affords diverse CF-substituted N-heterocycles. We first reacted TFISYs as a two-atom synthon with readily available azoalkenes and then subjected the products to metal-free formal (4+2) cycloaddition chemistry. This protocol features mild conditions and broad substrate scope, is simple to operate, and provides highly functionalized trifluoromethylpyridazines that are widely found in bioactive molecules.

Fall Direction Detection in Motion State Based on the FMCW Radar.

Accurately detecting falls and providing clear directions for the fall can greatly assist medical staff in promptly developing rescue plans and reducing secondary injuries during transportation to the hospital. In order to facilitate portability and protect people's privacy, this paper presents a novel method for detecting fall direction during motion using the FMCW radar. We analyze the fall direction in motion based on the correlation between different motion states.

Emotion Recognition Using Different Sensors, Emotion Models, Methods and Datasets: A Comprehensive Review.

In recent years, the rapid development of sensors and information technology has made it possible for machines to recognize and analyze human emotions. Emotion recognition is an important research direction in various fields. Human emotions have many manifestations.

Rhodium-Catalyzed 1,4-Aryl Rearrangement of Sulfur Ylide for the Synthesis of 2-Pyridyl Thioethers.

We report a novel rhodium-catalyzed rearrangement involving N-substituted 2-thiopyridones and diazoesters. This reaction proceeds through the rhodium-catalyzed formation of sulfur ylides, followed by a direct C-N bond cleavage to achieve N-to-C 1,4-pyridyl migration. The protocol can be used to construct various thiopyridines possessing tetrasubstituted carbon stereocenters in moderate to excellent yields, which expands the transformation pattern of sulfur ylide intermediates in rearrangement reactions.

Tracing the origin of an imported HIV-1 sub-subtype A6 strain first identified in Zhejiang Province, China.

Human migration and mobility have been identified as key drivers of HIV dissemination among nations, which increases the problem of genetic diversity. Here, we report the near full-length genome of HIV-1 A6 identified in a female patient in the remote mountain area of Lishui, Zhejiang Province, which is the first time A6 has been reported in China. The near full-length genome was amplified with two large amplicons of 5.

Continuous epitaxy of single-crystal graphite films by isothermal carbon diffusion through nickel.

Multilayer van der Waals (vdW) film materials have attracted extensive interest from the perspective of both fundamental research and technology. However, the synthesis of large, thick, single-crystal vdW materials remains a great challenge because the lack of out-of-plane chemical bonds weakens the epitaxial relationship between neighbouring layers. Here we report the continuous epitaxial growth of single-crystal graphite films with thickness up to 100,000 layers on high-index, single-crystal nickel (Ni) foils.

Highly Efficient and -Selective C-H Functionalization of Polystyrene Providing a Versatile Platform for Diverse Applications.

Postpolymerization modification of polystyrene (PS) can afford numerous value-added materials with different functions and applications, but it has been hampered by the lack of efficient methods. We report herein a highly efficient and -selective conversion of the C-H bonds of the aromatic ring of PS into diverse functional groups using a combination of thianthrenation and thio-Suzuki-Miyaura coupling reaction. Notably, the thianthrenation efficiency of PS is as high as 99% and the degree of thianthrenation can be conveniently controlled using stoichiometric tuning of the amount of thianthrene--oxide added, resulting in 24-99 mol % thianthrenation.

Self-Assembled Aza-Boron-Dipyrromethene for Ferroptosis-Boosted Sonodynamic Therapy.

The presence of apoptosis inhibition proteins renders the cancer cells resistant to apoptosis, severely compromising the antitumor efficacy of sonodynamic therapy (SDT). Here, an intelligent anticancer nanoplatform based on an Aza-boron-dipyrromethene dye (denoted as Aza-BDY) is elaborately established for ferroptosis augmented SDT through cysteine (Cys) starvation. After endocytosis by tumor cells, Aza-BDY serves as both a ferroptosis inducing agent and a sonosensitizer for tumor treatment.

The emergence and transmission dynamics of HIV-1 CRF07_BC in Mainland China.

A total of 1155 partial gene sequences of human immunodeficiency virus (HIV)-1 CRF07_BC were sampled between 1997 and 2015, spanning 13 provinces in Mainland China and risk groups [heterosexual, injecting drug users (IDU), and men who have sex with men (MSM)] to investigate the evolution, adaptation, spatiotemporal and risk group dynamics, migration patterns, and protein structure of HIV-1 CRF07_BC. Due to the unequal distribution of sequences across time, location, and risk group in the complete dataset ('full1155'), subsampling methods were used. Maximum-likelihood and Bayesian phylogenetic analysis as well as discrete trait analysis of geographical location and risk group were carried out.

Omicron: Call for updated vaccines.

The Omicron SARS-CoV-2 variant was potentially generated from a chronically infected COVID-19 patient vaccinated with an messenger RNA (mRNA)- or non-mRNA-based vaccine, offering the opportunity for the virus to evolve and mutate to evade the body's immune response. To understand the significance of this SARS-CoV-2 variant and what it means for the global response to the pandemic, vaccinologists should systematically evaluate the role of mRNA- and non-mRNA-based vaccines in the generation of novel SARS-CoV-2 variants, including variants of concerns (VOCs) and interest (VOIs), that occur via breakthrough vaccine-elicited immunity. Although COVID vaccine boosters are likely to offer some protection and mRNA- or non-mRNA-based vaccines can be adapted to new variants, such as Omicron, the requirement of a booster so soon after full vaccination, with further shots potentially required, is of concern given the impacts on human health.

Concerns on the multiple nomenclature systems for SARS-CoV-2.

The multiple nomenclature systems of SARS-CoV-2 are confusing and have several issues. The emergence of variants of concern and variants of interest has posed an increased risk to global health. To assist with public discussion and communication with nonscientific audiences about significant mutations, and ultimately to inform the ongoing response to the COVID-19 pandemic, we scientists need to develop easy-to-pronounce and nonstigmatizing labels for significant mutations.