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For metal-free low-dimensional ferromagnetic materials, a hopeful candidate for next-generation spintronic devices, investigating their magnetic mechanisms and exploring effective ways to regulate their magnetic properties are crucial for advancing their applications. Our work systematically investigated the origin of magnetism of a graphitic carbon nitride (Pca21 C4N3) monolayer based on the analysis on the partial electronic density of states. The magnetic moment of the Pca21 C4N3 originates from the spin-split of the 2pz orbit from special carbon (C) atoms and 2p orbit from N atoms around the Fermi energy, which was caused by the lone pair electrons in nitrogen (N) atoms. Notably, the magnetic moment of the Pca21 C4N3 monolayer could be effectively adjusted by adsorbing nitric oxide (NO) or oxygen (O2) gas molecules. The single magnetic electron from the adsorbed NO pairs with the unpaired electron in the N atom from the substrate, forming a Nsub-Nad bond, which reduces the system’s magnetic moment from 4.00 μB to 2.99 μB. Moreover, the NO adsorption decreases the both spin-down and spin-up bandgaps, causing an increase in photoelectrical response efficiency. As for the case of O2 physisorption, it greatly enhances the magnetic moment of the Pca21 C4N3 monolayer from 4.00 μB to 6.00 μB through ferromagnetic coupling. This method of gas adsorption for tuning magnetic moments is reversible, simple, and cost-effective. Our findings reveal the magnetic mechanism of Pca21 C4N3 and its tunable magnetic performance realized by chemisorbing or physisorbing magnetic gas molecules, providing crucial theoretical foundations for the development and utilization of low-dimensional magnetic materials.

Ultrawide-bandgap (UWBG) semiconductors, surpassing GaN with a bandgap of 3.4 eV, offer distinct advantages in high-temperature, high-frequency, and radiation-resistant applications. Specifically, two-dimensional (2D) UWBG materials play a crucial role in the miniaturization of practical devices. Here, employing first-principles calculations, we explore the properties of the polar iodate BiO(IO3) in its 2D monolayer configuration, boasting a bandgap of 3.61 eV. Our calculations confirm the feasibility of deriving 2D BiO(IO3) monolayer from its bulk counterpart while retaining structural stability at room temperature. The UWBG BiO(IO3) monolayer exhibits remarkable ultraviolet absorption, mechanical flexibility, and favorable electronic transport behavior. Notably, the estimated electron mobility reaches an impressive 1353.13 cm2 V−1 s−1. Importantly, the 2D structure of BiO(IO3) displays robust in-plane piezoelectricity without the odd–even effect commonly observed in other 2D piezoelectric materials. The piezoelectric coefficients d21 and d22 of monolayer reach high values of 13.87 and 16.66 pm V−1, respectively, surpassing or closely approaching those of most well-studied 2D systems. The direct stacking configuration enables 2D BiO(IO3) materials to maintain robust piezoelectricity at different thicknesses. Charge injection simulations validate the electromechanical conversion process, aligning well with its piezoelectric properties. This suggests the promising application potential of 2D BiO(IO3) in devices such as micro-electro-mechanical systems.

Searching for novel two-dimensional (2D) materials with excellent properties is of great importance for the design of next generation nano-devices. Based on first-principles calculations, we propose an unexplored 2D monolayer PdTeI2 material, which can be prepared from its bulk crystal by exfoliation method. Our calculations show that monolayer PdTeI2 has excellent dynamical and thermal stability. The appropriate bandgap of 0.82 eV endows monolayer PdTeI2 with superior optical absorption capacity in the infrared and visible regions. Remarkably, the in-plane electron mobility of monolayer PdTeI2 is as high as 104cm2v-1s-1, which is much larger than those of most previously reported 2D materials. Based on the combination of density functional theory and non-equilibrium Green’s function formalism, a large photocurrent of 40 a02/photon for photon energy of 1.0 eV is obtained under a small bias voltage in PdTeI2-based two-electrode optoelectronic devices, indicating the outstanding photoresponse characteristic of monolayer PdTeI2 in the infrared region. The large photocurrent, along with the high electron mobility and strong optical absorption make monolayer PdTeI2 a candidate material for future applications in novel optoelectronics and microelectronic devices, such as infrared photodetectors.

Abstract Millions of adenosine (A) to inosine (I) RNA editing events are reported and well‐studied in eukaryotes; however, many features and functions remain unclear in prokaryotes. By combining PacBio Sequel, Illumina whole‐genome sequencing, and RNA Sequencing data of two Klebsiella pneumoniae strains with different virulence, a total of 13 RNA editing events are identified. The RNA editing event of badR is focused, which shows a significant difference in editing levels in the two K. pneumoniae strains and is predicted to be a transcription factor. A hard‐coded Cys is mutated on DNA to simulate the effect of complete editing of badR. Transcriptome analysis identifies the cellular quorum sensing (QS) pathway as the most dramatic change, demonstrating the dynamic regulation of RNA editing on badR related to coordinated collective behavior. Indeed, a significant difference in autoinducer 2 activity and cell growth is detected when the cells reach the stationary phase. Additionally, the mutant strain shows significantly lower virulence than the WT strain in the Galleria mellonella infection model. Furthermore, RNA editing regulation of badR is highly conserved across K. pneumoniae strains. Overall, this work provides new insights into posttranscriptional regulation in bacteria.

Integrating artificial intelligence and new diagnostic platforms into routine clinical microbiology laboratory procedures has grown increasingly intriguing, holding promises of reducing turnaround time and cost and maximizing efficiency. At least one billion people are suffering from fungal infections, leading to over 1.6 million mortality every year. Despite the increasing demand for fungal diagnosis, current approaches suffer from manual bias, long cultivation time (from days to months), and low sensitivity (only 50% produce positive fungal cultures). Delayed and inaccurate treatments consequently lead to higher hospital costs, mobility and mortality rates. Here, we developed single-cell Raman spectroscopy and artificial intelligence to achieve rapid identification of infectious fungi. The classification between fungi and bacteria infections was initially achieved with 100% sensitivity and specificity using single-cell Raman spectra (SCRS). Then, we constructed a Raman dataset from clinical fungal isolates obtained from 94 patients, consisting of 115,129 SCRS. By training a classification model with an optimized clinical feedback loop, just 5 cells per patient (acquisition time 2 s per cell) made the most accurate classification. This protocol has achieved 100% accuracies for fungal identification at the species level. This protocol was transformed to assessing clinical samples of urinary tract infection, obtaining the correct diagnosis from raw sample-to-result within 1 h.

Abstract Despite the clinical benefit of androgen‐deprivation therapy (ADT), the majority of patients with advanced prostate cancer (PCa) ultimately develop lethal castration‐resistant prostate cancer (CRPC). In this study, we identified thioesterase superfamily member 6 (THEM6) as a marker of ADT resistance in PCa. THEM6 deletion reduces in vivo tumour growth and restores castration sensitivity in orthograft models of CRPC. Mechanistically, we show that the ER membrane‐associated protein THEM6 regulates intracellular levels of ether lipids and is essential to trigger the induction of the ER stress response (UPR). Consequently, THEM6 loss in CRPC cells significantly alters ER function, reducing de novo sterol biosynthesis and preventing lipid‐mediated activation of ATF4. Finally, we demonstrate that high THEM6 expression is associated with poor survival and correlates with high levels of UPR activation in PCa patients. Altogether, our results highlight THEM6 as a novel driver of therapy resistance in PCa as well as a promising target for the treatment of CRPC.

Metabolic interactions within gut microbiota play a vital role in human health and disease. Targeting metabolically interacting bacteria could provide effective treatments; however, obtaining functional bacteria remains a significant challenge due to the complexity of gut microbiota. Here, we developed a facile droplet-based approach to isolate and enrich functional gut bacteria that could utilize metabolites from an engineered butyrate-producing bacteria (EBPB) of anti-obesity potential. This involves the high throughput formation of single-bacteria droplets, followed by culturing “droplets” on agar plates to form discrete single-cell colonies. This approach eliminates the need for sophisticated s instruments to sort droplets and thus allows the operation hosted in a traditional anaerobic chamber. In comparison to the traditional culture, the droplet-based approach obtained a community of substantially higher diversity and evenness. Using the conditioned plates containing metabolites from the EBPB supernatant, we obtained gut bacteria closely associated or interacting with the EBPB. These include anaerobic Lactobacillus and Bifidobacterium, which are often used as probiotics. The study illustrates the potential of our approach in the search for the associated bacteria within the gut microbiota and retrieving those yet-to-be cultured.

Exploring the vibrational properties of experimental or theoretical finding of new phase two-dimensional (2D) materials is one key to expand their promising application. The GaGeTe monolayer with high carrier mobility, tunable band structure, and low cleavage energy attracts rapidly growing interests in electronics. However, their vibrational modes and phonon properties are not explored. Based on first-principles calculations within the framework of density functional perturbation theory, we systematically study the lattice vibrational modes as well as phonon thermal conductivity of single-layer GaGeTe, which could be exfoliated from the experimentally synthesized GaGeTe crystal. We find that the frequencies and intensities of A1g and Eg Raman modes, contributing to the main peaks in Raman spectra of monolayer GaGeTe, show distinct responses to different external strains. The calculated lattice thermal conductivity of GaGeTe is about 58 Wm-1 K−1, which is comparable to that of MoS2 (around 52 Wm−1K−1) and two orders of magnitude lower than that of graphene (2000 Wm−1K−1) at room temperature. This is mainly due to the partial couple for acoustic branches and low frequency optic phonon branches, moderate group velocity, strong anharmonic ZA phonon branch. Moreover, atom substitution at tellurium could be as an effective strategy to further decrease lattice thermal conductivity. Our findings fill in the gap about the thermal transport properties of GaGeTe monolayer and trigger for further experimental verification of the predicted properties.

As is well known, NO2 adsorption plays an important role in gas sensing and treatment because it expands the residence time of compounds to be treated in plasma–catalyst combination. In this work, the adsorption behaviors and mechanism of NO2 over pristine and Se-vacancy defect-engineered WSSe monolayers have been systematically investigated using density functional theory (DFT). The adsorption energy calculation reveals that introducing Se vacancy acould result in a physical-to-chemical adsorption transition for the system. The Se vacancy, the most possible point defect, could work as the optimum adsorption site, and it dramatically raises the transferred-electron quantities at the interface, creating an obviously electronic orbital hybridization between the adsorbate and substrate and greatly improving the chemical activity and sensing sensitivity of the WSSe monolayer. The physical-to-chemical adsorption transition could meet different acquirements of gas collection and gas treatment. Our work broadens the application filed of the Janus WSSe as NO2-gas-sensitive materials. In addition, it is found that both keeping the S-rich synthetic environments and applying compression strain could make the introduction of Se vacancy easier, which provides a promising path for industrial synthesis of Janus WSSe monolayer with Se vacancy.

With the increasing demands for the miniaturization of ferroelectricity-enabled electronic devices, it is highly desirable that the ferroelectricity would exist in low-dimensional materials. However, those ferroelectrics, especially one-dimensional (1D) ones, are still limited. Herein, based on the first-principles calculations, 1D ferroelectricity in novel InSeI nanowires with noncentrosymmetric P42 space group is explored, which could possess three different paths for the reversal of electric polarization. The minimum energy barrier of 97 meV/f.u. for the polarization reversal, comparable with those of other low-dimensional ferroelectrics, could be achieved through a unique four-step concerted process. According to ab initio molecular dynamics simulations, the Curie temperature of the proposed P42-InSeI nanowires is estimated to about 866 K, above room temperature. The electronic structure and carrier mobility of the nanowires are also studied, demonstrating that they could be promising materials in nanoelectronics such as high-density nonvolatile memories due to their stable array structures formed by van der Waals interactions.

Solid lubricant WS2 was encapsulated in the dimples on the cylinder surface by the hot-pressing method. The tribological and releasing performance of the as-prepared sample were investigated under high temperature conditions. The results indicate that, compared with the original cylinder, WS2 in the dimples exhibited better tribological properties at high temperature than at room temperature. The average friction coefficients of the as-prepared samples were about 0.13 and 0.15 at high temperature and room temperature, respectively, which were 27.8% and 16.7% lower than that of the original cylinder, respectively. Moreover, compared with the original cylinder, the anti-adhesion time of the as-prepared sample increased 2.3-fold. Additionally, the reduced viscosity of the lubricating oil caused by high temperature accelerated the erosion effect and release rate of the solid lubricant in the dimples. Thus, the polar additives in the lubricating oil and the chemical reactions between the cylinder substrates and solid lubricants that WS2 released from the dimples are the main factors in friction reduction. This study provides some guidance for anti-friction design of cylinders under high temperature conditions.

Two-dimensional (2D) piezoelectric materials that can achieve conversion between mechanical and electrical energy are of notable interest for functional materials. However, most 2D materials have only in-plane piezoelectricity, which limits their applications in vertically integrated nanoelectromechanical systems. Here, we employ first-principles calculations to predict properties of a family of piezoelectric materials—Li-based ternary chalcogenides LiMX2 (M = Al, Ga, and In; X = S, Se, and Te). These materials exhibit the coexistence of intrinsic out-of-plane and in-plane piezoelectricity with coefficients d11 = 1.48–8.66 pm/V and d31 = 0.24–0.83 pm/V, respectively. The out-of-plane piezoelectric coefficients d31 of LiAlSe2, LiGaTe2, and LiAlTe2 in particular are as high as 0.61, 0.70, and 0.83 pm/V, respectively, much larger than those of most reported 2D materials. This enhancement can be attributed to the unique double-buckled stacking structure of these LiMX2 monolayers. It is also found that the in-plane piezoelectricity is highly dependent on the ratio of anion and cation polarizabilities, whereas the out-of-plane piezoelectricity exhibits a complicated variation trend with respect to the order of atomic number. The coexistence of large out-of-plane and in-plane piezoelectricity endows LiMX2 monolayers with potential applications in both directional and nondirectional piezoelectric devices.

In video coding, rate distortion optimized quantization (RDOQ), a popular version of soft-decision quantization (SDQ), achieves superior coding performance, however is ill-suited for hardware implementation due to its inherent sequential processing. On the other hand, deadzone hard-decision quantization (HDQ) is friendly to hardware implementation, however suffers from non-negligible coding performance degradation. This paper proposes a content-adaptive deadzone offset model to improve the coefficient-wise deadzone HDQ by imitating the behavior patterns of RDOQ. The contributions of this paper are characterized by twofold. On one hand, this work formulates seeking optimal deadzone offset model as a problem of binary classification, and analyzes the distribution characteristics of the optimal deadzone offsets obtained from samples by fully imitating RDOQ, and then derives adaptive deadzone offset model by maximizing the right classification probability of offset-induced rounding in HDQ. On the other hand, the distribution parameters of DCT coefficients are measured in a position-wise way, and the adaptive deadzone model is built by applying Maximum a posterior estimation method according to three characteristic parameters, i.e. quantization step size, parameter of DCT coefficients, and quantization remainder, in the sense of rate distortion optimization. Simulation results verify that the proposed adaptive HDQ algorithm, in comparison with fixed-offset HDQ, achieves 0.54% and 0.52% bit rate saving on average with almost negligible complexity increment. Simultaneously, the proposed algorithm only sacrifices smaller than 0.55% and 0.54% increment in terms of BD-BR in comparison with RDOQ. The proposed HDQ is well-suited for hardwired video coding implementation.

Multidrug-resistant (MDR) Acinetobacter baumannii strains can cause severe infections in intensive care units, and are rapidly developing resistance to the last-resort of existing antibiotics, posing a major global threat to health care system. Berberine hydrochloride (BBH), a kind of isoquinoline alkaloids extracted from Berberis and other plants, has been widely used as an antibacterial medicine for its reliable therapeutic efficiency. The in vitro synergistic effects of BBH with antibiotics against MDR A. baumannii were determined. BBH alone had weak antimicrobial activity (e.g., MIC≥256 mg/L) against MDR A. baumannii. However, it dramatically increased the susceptibility of MDR strains against antibiotics with FICI values

Some p53 mutants promote invasive migration of cancer cells and metastasis of tumours in vivo. However the key mechanistic details behind these phenomena remain unclear. Here the authors propose a non-cell autonomous mechanism involving fibroblasts, whereby mutant p53-expressing cancer cells activate an exosome-mediated mechanism that influences integrin recycling in fibroblasts, thus influencing extracellular matrix remodelling to favour cancer cell invasion and migration.

Temporal lobe epilepsy (TLE) is a form of refractory focal epilepsy, which includes a latent period and a chronic period. Microelectrode arrays capable of multi-region detection of neural activities are important for accurately identifying the epileptic focus and pathogenesis mechanism in the latent period of TLE. Here, we fabricated multi-shank MEAs to detect neural activities in the DG, hilus, CA3, and CA1 in the TLE rat model. In the latent period in TLE rats, seizures were induced and changes in neural activities were detected. The results showed that induced seizures spread from the hilus and CA3 to other areas. Furthermore, interneurons in the hilus and CA3 were more excited than principal cells and exhibited rhythmic oscillations at approximately 15 Hz in grand mal seizures. In addition, the power spectral density (PSD) of neural spikes and local field potentials (LFPs) were synchronized in the frequency domain of the alpha band (9–15 Hz) after the induction of seizures. The results suggest that fabricated MEAs have the advantages of simultaneous and precise detection of neural activities in multiple subregions of the hippocampus. Our MEAs promote the study of cellular mechanisms of TLE during the latent period, which provides an important basis for the diagnosis of the lesion focus of TLE.

Carotenoids harvest energy from light and transfer it to chlorophylls during photosynthesis. Here, Feng et al. perform ab initio calculations on excited-state dynamics and simulated 2D electronic spectrum of carotenoids, supporting the existence of a new excited state in carotenoids.

The secretome from cancer and stromal cells contributes to the creation of a microenvironment, which in turn contributes to invasion and angiogenesis. Here, the authors compare the secretomes of immortalized normal fibroblasts and cancer-derived fibroblast and identify CLIC3 as a driver of cancer progression.

The spread of antibiotic resistance genes (ARGs) has become an emerging threat to the global health. Although horizontal gene transfer (HGT) is regarded as one of the major pathways, more evidence has shown the significant involvement of vertical gene transfer (VGT). However, traditional cultivation-based methods cannot distinguish HGT and VGT, resulting in often contradictory conclusions. Here, single-cell microfluidics with time-lapse imaging has been successfully employed to dissect the contribution of plasmid-mediated HGT and VGT to ARG transmission in an environmental community. Using Escherichia coli with an ARG-coded plasmid pKJK5 with trimethoprim resistance as the donor, we quantified the effects of three representative antibiotics (trimethoprim, tetracycline and amoxicillin) on the ARG transfer process in an activated sludge bacterial community. It was found that HGT was influenced by the inhibitory mechanism of an antibiotic and its targets (donor, recipient alone or together), whereas VGT contributes significantly to the formation of transconjugants and consequently ARG spreading. Trimethoprim is highly resisted by the donor and transconjugants, and its presence significantly increased both the HGT and VGT rates. Although tetracycline and amoxicillin both inhibit the donor, they showed different effects on HGT rate as a result of different inhibitory mechanisms. Furthermore, we show the kinetics of HGT in a community can be described using an epidemic infection model, which in combination with quantitative measure of HGT and VGT on chip provides a promising tool to study and predict the dynamics of ARG spread in real-world communities. Keywords: Cell tracking, Microfluidics, Antibiotics, Antibiotic resistance genes, Horizontal gene transfer, Vertical gene transfer

The bis(benzimidazol-1-yl)methane molecule of the title compound, C15H12N4·2H2O, displays a trans conformation with a twofold axis running through the methylene C atom. Two adjacent water molecules are bonded to this molecule through O—H...N hydrogen bonds, forming a trimer. Adjacent trimers are connected together via C—H...O interactions, forming a chain running along the b-axis direction. Two such chains are joined together via π–π interactions [centroid–centroid distance = 3.556 (2) Å], forming double chains, which are connected via the water molecules through C—H...O associations, forming a sheet structure. The sheets are stacked on top of each other along the a-axis direction and connected through O—H...O and C—H...O interactions, forming a three-dimensional ABAB layer network structure.