Browse Articles

The splicing factor SRSF6 mediates ferroptosis resistance in head and neck squamous cell carcinoma through induction of stearoyl-CoA desaturase

Near‐Infrared Emissive Molecular Carbons Based on Quadruple [n]Helicenes

Abstract We present a molecular design strategy that combines structural multiplicity and π‐extension on a quaterrylene diimide scaffold to construct efficient near‐infrared (NIR) circularly polarized luminescence (CPL) emitters. Through a carefully controlled synthesis involving sequential regioselective Suzuki coupling followed by Sholl‐type oxidative cyclization, we successfully obtained two novel quadruple [n]helicenes ( QnH ). Comprehensive experimental characterization and theoretical calculations demonstrated their distinct configurational preferences: Q5H exclusively adopted the meso ( P , P , M , M ) configuration, while Q6H produced only the ( P , P , P , P )/( M , M , M , M ) enantiomeric pair. Single‐crystal X‐ray diffraction unambiguously confirmed the unique “four‐bladed propeller” structure of ( P , P , M , M )‐ Q5H . Both compounds demonstrated intense NIR fluorescence emission with photoluminescence quantum yields ( Φ PL ) of 47% for Q5H and 37% for Q6H . The chiral ( P , P , P , P )/( M , M , M , M )‐ Q6H enantiomers showed exceptional chiroptical properties, including intense Cotton effects reached 719 M −1 cm −1 at 410 nm, a high absorption dissymmetry factor | g abs | of 0.035, and prominent CPL activity across 600–800 nm with a CPL brightness ( B CPL ) of 93 M −1 cm −1 .

Rational design of a multi epitope vaccine against Salmonella typhi via subtractive proteomics, reverse vaccinology and molecular modeling

Dual-specificity mitogen-activated protein kinase kinases can use ADP to phosphorylate MAP kinases in vitro

Frontispiece: Alkali Metal Cations Impact the Selectivity of Radical‐Mediated Electrochemical C─H Chlorination

Polymorphic α‐Glucans as Structural Scaffolds in <i>Cryptococcus</i> Cell Walls for Chitin, Capsule, and Melanin: Insights From ¹³ C and ¹ H Solid‐State NMR

Abstract Cryptococcus species are major fungal pathogens responsible for life‐threatening infections in approximately a million individuals globally each year, with alarmingly high mortality rates. These fungi are distinguished by a distinctive cell wall architecture further reinforced by two virulence‐associated layers, melanin and capsule, rendering them insensitive to antifungal agents targeting the cell wall, such as echinocandins. The molecular interplay between these three biomolecular layers remains poorly understood. Here, we employ solid‐state NMR spectroscopy to examine intact cells of both wild‐type and capsule‐deficient strains of C. neoformans , along with melanized cells. High‐resolution 13 C and 1 H data revealed five distinct structural forms of α‐1,3‐glucans that play versatile roles in forming the rigid cell wall scaffold by interacting with chitin microfibrils and chitosan, and in stabilizing the mobile matrix by associating with β‐1,6‐glucan and a small fraction of β‐1,3‐glucan. Two primary forms of α‐1,3‐glucans were distributed throughout the wall, capable of hosting melanin deposition in the inner domain and capsule attachment on the cell surface. These findings offer a paradigm shift in understanding the cryptococcal cell wall and its interaction with two key virulence factors on opposite sides, raising critical biochemical questions that could inform the development of more effective antifungal treatments for cryptococcosis.

CNN-LSTM-AM approach for outdoor wireless optical communication systems

Abstract This paper introduces the enhancement of Visible Light Communications (VLC) for V2V using artificial intelligence models. Different V2V scenarios are simulated. The first scenario considers a specific longitudinal separation and a variable lateral shift between vehicles. The second scenario assumes random longitudinal separation and a specific lateral shift between vehicles. Significant obstacles that impair performance and dependability in V2V communication systems include bit errors, high power consumption, and interference. By combining Convolutional Neural Networks (CNNs), Generative Adversarial Network (GAN), Gated Recurrent Unit (GRU), and Deep Denoising Autoencoder (DDAE), this paper suggests a deep learning-based system to address these issues. The framework comprises four modules, a power reduction module that uses a GAN to generate low-power signals while maintaining signal quality; a performance enhancement module that uses GRU, a Bit Error Rate (BER) reduction module that uses a DDAE to denoise the received signal and minimize errors; and an interference cancellation module that uses a CNN-based U-Net to separate the desired signal from interference. It is shown that the suggested model significantly improves throughput, power efficiency, BER reduction, and interference cancellation. In dynamic and noisy contexts, our study offers a reliable and scalable way to improve the performance and dependability of V2V communication systems. The CNN-U-Net-GAN-GRU-DDAE model outperforms other models, including CNN-U-Net, CNN-U-Net-GAN, and CNN-U-Net-GAN-GRU, achieving the best results by an average percentage 13.6%, 14.4% and 4.2% respectively. By comparing this work with previous works, we deduce that the improving average percentage for our work by 31.7%.

Sterol regulation in Komagataella phaffii: Identification of sterol regulatory element binding proteins and their activation pathway

A Genetically Encoded Homocysteine Precursor to Probe Protein Active Sites and to Addict <i>Escherichia coli</i> to a Noncanonical Amino Acid Directly Involved in Catalysis

Abstract Noncanonical amino acids (ncAAs) incorporated into proteins by stop codon suppression are powerful tools to probe and expand protein structure and function. Although homocysteine (Hcy) is a ubiquitous, naturally occurring amino acid, it was excluded from the universal genetic code. Hcy is very interesting, yet mostly unexplored, for probing protein active sites because of its subtle structural and electronic differences from cysteine and serine, which are widespread catalytic residues in enzymes. We report the genetic encoding of a new protected Hcy precursor, HcyX, that can be conveniently deprotected by chemical reductants or bioorthogonal reagents. We find varying and sometimes remarkable levels of activity for different purified enzymes with Hcy at catalytic positions. By exploiting partial intracellular deprotection to Hcy, we show that two proteins rendered Hcy‐dependent, an intein and thymidylate synthase, can rescue growth of Escherichia coli by catalyzing a reaction essential for cell survival. To the best of our knowledge, these are the first examples in which cell growth is linked to a genetically incorporated ncAA directly involved in catalysis. We further demonstrate that Hcy‐based disulfide bonds are chemically more stable than cysteine disulfides. Together, these findings open new paths for the experimental evolution of the genetic code.

Determinants of forearm bone mineral density in male athletes with different osteogenic index of training

Discovery of thiacyanine dyes as a new class of potent coronavirus inhibitors that suppress viral RNA synthesis

Research on surface subsidence laws and prediction models under repeated mining of multiple coal seams

Sialic acid identity modulates host tropism of sialoglycan-binding viridans group streptococci

Ag⁺‐Mediated Structural Reconstruction of a Metastable Cu ₃₅ Cluster Toward Cu–Ag Heterometallic Architectures for Superior Electrocatalytic CO ₂ ‐to‐Ethanol Conversion

Abstract Controlled structural transformations of metal nanoclusters (NCs) via dynamic bond reorganization provide fundamental insights into cluster reactivity and open avenues for functionality tuning. Here, we report a thiacalix[4]arene‐protected Cu(I)‐alkynide cluster, {NaCu 35 (TC4A) 4 (Ph‐C≡C) 20 } ( Cu 35 ), which exhibits remarkable structural plasticity. This metastable cluster can grow into a Cu 36 species via ion substitution or undergo thermal‐induced fragmentation to form a smaller Cu 14 cluster. Under thermal etching by Ag + ion, structural reconstruction is triggered, leading to the formation of the bimetallic Cu 14 Ag 6 and Cu 40 Ag 16 clusters. The structural reorganization significantly alters the catalytic outcomes in electrocatalytic CO 2 reduction. Although the monometallic Cu 35 and Cu 14 favor gaseous CH 4 /C 2 H 4 production, the bimetallic Cu 14 Ag 6 demonstrates remarkable selectivity for ethanol synthesis. Notably, Cu 14 Ag 6 achieves an impressive Faradaic efficiency (FE) of 49.27% for ethanol production, alongside a high partial current density of −67.94 mA cm −2 . This marks the highest ethanol selectivity reported to date for atomically precise cluster catalysts. Mechanistic investigations reveal that, compared to homometallic Cu⋯Cu dual sites (which typically favor C 2 H 4 ), the unique Ag⋯Cu⋯Cu trimetallic microstructure in Cu 14 Ag 6 is more thermodynamically favorable for asymmetric C─C coupling between *CHO and *OCH 2 , facilitating the formation of the key *CHO−*OCH 2 intermediate, which drives the ethanol‐selective pathway.

Tobacco smoking and the risk of aortic aneurysm in the UK biobank

Abstract Smoking is an established risk factor for aortic aneurysm, however, few studies have investigated the associations with different aortic aneurysm subsites. The aim of this study was to investigate whether different tobacco smoking metrics and smoking cessation was associated with aortic aneurysm and its subsites in the UK Biobank. The analysis included 495,993 participants, aged 37–73 years. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between smoking and aortic aneurysm. After 12.3 years of follow-up, 3,353 incident cases and 184 deaths from aortic aneurysm were identified. The HRs (95% CIs) of aortic aneurysm incidence for current and former vs. never smokers were 4.32 (3.93–4.76) and 1.70 (1.56–1.84), respectively, and for ≥ 20 vs. &lt;10 cigarettes per day was 5.67 (4.93–6.52), and similar results were observed for pack-years and duration of smoking. At ≥ 30 years of smoking cessation vs. current smoking risk was substantially reduced (0.23, 0.20–0.27) and comparable to never smoking (0.22, 0.20–0.25). Strong positive HRs were observed for current vs. never smoking and abdominal (8.90, 7.79–10.16), thoracoabdominal (11.64, 4.20-32.25), and unspecified site (2.06, 1.61–2.65), ruptured (10.47, 6.12–17.90) and non-ruptured (4.19, 3.80–4.62) aortic aneurysms, but no association was observed for thoracic aortic aneurysm (1.13, 0.88–1.44). Smoking was strongly associated with increased risk of aortic aneurysm and most subtypes. Smoking cessation for ≥ 30 years strongly reduced risk to levels comparable of never smokers. These findings support public health policies promoting smoking prevention and cessation.

Proteasomal regulation of ASK family kinases dictates cell fate under hyperosmotic stress

Surgical outcomes of minimally invasive microscopic debridement in thoracolumbar pyogenic spondylodiscitis

Single-chain Fab chain-exchange (scFab-PACE) converts targeted prodrugs into functional T cell engagers on tumor cells

High H ₂ Recovery Properties of Carbon Molecular Sieve Membranes with Sub‐Nanometer Precision Derived from Dual Cross‐Linked Polyimide Precursor

Abstract Energy‐efficient purification technologies are essential for advancing a sustainable hydrogen economy. Carbon molecular sieve membranes (CMSMs) have emerged as promising candidates; however, achieving precise sub‐Angstrom micropore control and ensuring structural stability remain significant challenges. Here, we introduce a dual cross‐linked strategy to engineer microporosity of the resulting CMSMs by utilizing a decarbonylated 3,5‐diaminobenzoic acid (DABA)‐induced rigid network ( Type A ) in conjunction with a sulfur bond‐induced flexible network ( Type B ). The 6F‐D‐S‐CMS membrane exhibits a record‐high H 2 permeability of 3464 Barrer with H 2 /CH 4 selectivity of 3807, surpassing the Robeson upper bound. Upon pyrolysis at 850 °C, the 6F‐D‐S‐CMS‐850 membrane achieves exceptional selectivity values: H 2 /CH 4 at 6538, H 2 /N 2 at 1634, and H 2 /CO 2 at 149—outperforming most reported CMS membranes. Molecular dynamics simulations revealed that the Type B network suppressed CH 4 adsorption (3.6 cm 3  g −1  versus 6.2 cm 3  g −1 ) and significantly enhanced the small pore volume ratio ( V H2 / V CH4 : 10.3 versus 2.1) during carbonization, thereby eliminating non‐selective pathways and reducing inter‐skeletal spacing (4.09 Å versus 3.78 Å), which enables precise molecular sieving. This rigid‐flexible cross‐linked strategy for CMSMs establishes a scalable blueprint for next‐generation hydrogen production.

Synthesis and characterization of branched multiblock copolymers of polyhydroxybutyrate (PHB) autoxidized fatty acid and polymethylmethacrylate (PMMA)