Undescribed polyketides from endophytes associated with the critically endangered conifer Abies beshanzuensis.

Four undescribed polyketides, beshanzones A (1) and B (2) as well as beshanhexanols A (3) and B (4), along with three known ones (5-7) were isolated from the rice fermentation of two endophytic fungi associated with the critically endangered Chinese endemic conifer Abies beshanzuensis. γ-Butyrolactone derivatives 1, 2, and 5 were isolated from Phomopsis sp. BSZ-AZ-2, an interesting strain that drawn our attention this time. The cyclohexanol derivatives 3, 4, 6, and 7 were obtained during a follow-up investigation on Penicillium commune BSZ-P-4-1. The chemical structures including absolute configurations of compounds 1-4 were determined by spectroscopic methods, Mo2(OAc)4 induced electronic circular dichroism (IECD), GIAO NMR calculations and DP4+ probability analyses. In particular, compound 2 contains a novel 5/5 bicyclic ring system, which might be biogenetically derived from the known compound 5 through hydrolysis followed by an Aldol reaction. All isolates were evaluated for their antimicrobial activities against a small panel of bacterial and fungal pathogens. Compounds 6 and 7 showed moderate inhibitory activities against Candida albicans, with MIC values of 16 and 32 µg/mL, respectively.

On-chip silicon photonic micro-ring processor lights up optical image encryption.

Optical image encryption has long been an important concept in the fields of photonic network processing and communication. Here, we propose a convolution-like operation-based optical image encryption algorithm exploiting a silicon photonic multiplexing architecture to achieve content security. Particularly, the encryption process is completed in a 3 × 3 cross-shaped photonic micro-ring resonator (MRR) array on chip. For the first time, to the best of our knowledge, this algorithm encodes information in an integrated intensity modulation, effectively reducing the encoding difficulty. Moreover, the high reliability and scalability of optical encryption are ensured using both linear and nonlinear operations on photonic chips according to characteristics of MRRs. As the encryption and decryption experiments show, the image restoration accuracy of our optical encryption algorithm exceeds 99% under real system noise at the pixel level, indicating its noise-robust property. Meanwhile, the peak signal-to-noise ratios of the restored and encrypted images are >60 and <15 dB, respectively, revealing both the high accuracy of the restored image and the small correlation between the encrypted and original images. This work adds to the rapidly expanding field of optical image encryption on photonic chips.

Transmissibility of the variant of concern for SARS-CoV-2 in six regions.

Introduction: Differences in transmissibility of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) in different districts are hard to assess. To address this, our study focused on calculating the Real-time reproduction number (R t ) for these variants in different regions. Methods: According to the criteria defined by the World Health Organization (WHO), the global landscape was categorized into six distinct regions. In each region, the predominant SARS-CoV-2 variant was first identified based on the proportion of variant sequencing analysis results. Then, using serial interval (SI) parameters, we calculated R t for the relevant Variant of Concern (VOC) in each region. This approach enabled us to compare the R t values of the same variant across different regions and analyze the transmissibility of each region's variant in relation to the overall situation in that region. Results: The progression of VOC for SARS-CoV-2 shows regional variations. However, a common sequence of evolution is observed: Wild-type → Alpha → Beta → Delta → Omicron. Moreover, an increasing trend is discerned within diverse regions where the shift in R t of distinct VOC corresponds with the overarching R t route of SARS-CoV-2 in specific regions. Conclusion: As the COVID-19 pandemic advances, regional epidemiological trends are aligning, likely due to similar virus mutations and shared public health strategies, suggesting opportunities for standardized global responses.

Comparative transcriptome analysis reveals genes involved in trichome development and metabolism in tobacco.

BACKGROUND: The glandular trichomes of tobacco (Nicotiana tabacum) can efficiently produce secondary metabolites. They act as natural bioreactors, and their natural products function to protect plants against insect-pests and pathogens and are also components of industrial chemicals. To clarify the molecular mechanisms of tobacco glandular trichome development and secondary metabolic regulation, glandular trichomes and glandless trichomes, as well as other different developmental tissues, were used for RNA sequencing and analysis. RESULTS: By comparing glandless and glandular trichomes with other tissues, we obtained differentially expressed genes. They were obviously enriched in KEGG pathways, such as cutin, suberine, and wax biosynthesis, flavonoid and isoflavonoid biosynthesis, terpenoid biosynthesis, and plant-pathogen interaction. In particular, the expression levels of genes related to the terpenoid, flavonoid, and wax biosynthesis pathway mainly showed down-regulation in glandless trichomes, implying that they lack the capability to synthesize certain exudate compounds. Among the differentially expressed genes, 234 transcription factors were found, including AP2-ERFs, MYBs, bHLHs, WRKYs, Homeoboxes (HD-ZIP), and C2H2-ZFs. These transcription factor and genes that highly expressed in trichomes or specially expressed in GT or GLT. Following the overexpression of R2R3-MYB transcription factor Nitab4.5_0011760g0030.1 in tobacco, an increase in the number of branched glandular trichomes was observed. CONCLUSIONS: Our data provide comprehensive gene expression information at the transcriptional level and an understanding of the regulatory pathways involved in glandular trichome development and secondary metabolism.

Theoretical Epidemiology Needs Urgent Attention in China.

The mathematical method to which theoretical epidemiology belongs is one of the three major methodologies in epidemiology. It is of great value in diagnosing infectious disease epidemic trends and evaluating the effectiveness of prevention and control measures. This paper aims to summarize the brief history of the development of theoretical epidemiology, common types of mathematical models, and key steps to develop a mathematical model. It also provides some thoughts and perspectives on the development and application of theoretical epidemiology in China.

Assessment of Bitterness in Non-Charged Pharmaceuticals with a Taste Sensor: A Study on Substances with Xanthine Scaffold and Allopurinol.

Taste sensors with an allostery approach have been studied to detect non-charged bitter substances, such as xanthine derivatives, used in foods (e.g., caffeine) or pharmaceuticals (e.g., etofylline). In this study, the authors modified a taste sensor with 3-bromo-2,6-dihydroxybenzoic acid and used it in conjunction with sensory tests to assess the bitterness of non-charged pharmaceuticals with xanthine scaffolds (i.e., acefylline and doxofylline), as well as allopurinol, an analogue of hypoxanthine. The results show that the sensor was able to differentiate between different levels of sample bitterness. For instance, when assessing a 30 mM sample solution, the sensor response to acefylline was 34.24 mV, which corresponded to the highest level of bitterness (τ = 3.50), while the response to allopurinol was lowest at 2.72 mV, corresponding to relatively weaker bitterness (τ = 0.50). Additionally, this study extended the application of the sensor to detect pentoxifylline, an active pharmaceutical ingredient in pediatric medicines. These results underscore the taste sensor's value as an additional tool for early-stage assessment and prediction of bitterness in non-charged pharmaceuticals.

Structured-Light 3D Imaging Based on Vector Iterative Fourier Transform Algorithm.

Quasi-continuous-phase metasurfaces overcome the side effects imposed by high-order diffraction on imaging and can impart optical parameters such as amplitude, phase, polarization, and frequency to incident light at sub-wavelength scales with high efficiency. Structured-light three-dimensional (3D) imaging is a hot topic in the field of 3D imaging because of its advantages of low computation cost, high imaging accuracy, fast imaging speed, and cost-effectiveness. Structured-light 3D imaging requires uniform diffractive optical elements (DOEs), which could be realized by quasi-continuous-phase metasurfaces. In this paper, we design a quasi-continuous-phase metasurface beam splitter through a vector iterative Fourier transform algorithm and utilize this device to realize structured-light 3D imaging of a target object with subsequent target reconstruction. A structured-light 3D imaging system is then experimentally implemented by combining the fabricated quasi-continuous-phase metasurface illuminated by the vertical-cavity surface-emitting laser and a binocular recognition system, which eventually provides a new technological path for the 3D imaging field.

Asymmetric magma plumbing system beneath Axial Seamount based on full waveform inversion of seismic data.

The architecture of magma plumbing systems plays a fundamental role in volcano eruption and evolution. However, the precise configuration of crustal magma reservoirs and conduits responsible for supplying eruptions are difficult to explore across most active volcanic systems. Consequently, our understanding of their correlation with eruption dynamics is limited. Axial Seamount is an active submarine volcano located along the Juan de Fuca Ridge, with known eruptions in 1998, 2011, and 2015. Here we present high-resolution images of P-wave velocity, attenuation, and estimates of temperature and partial melt beneath the summit of Axial Seamount, derived from multi-parameter full waveform inversion of a 2D multi-channel seismic line. Multiple magma reservoirs, including a newly discovered western magma reservoir, are identified in the upper crust, with the maximum melt fraction of ~15-32% in the upper main magma reservoir (MMR) and lower fractions of 10% to 26% in other satellite reservoirs. In addition, a feeding conduit below the MMR with a melt fraction of ~4-11% and a low-velocity throat beneath the eastern caldera wall connecting the MMR roof with eruptive fissures are imaged. These findings delineate an asymmetric shallow plumbing system beneath Axial Seamount, providing insights into the magma pathways that fed recent eruptions.

Pentacyclic triterpenoids as potential ACL inhibitors from the rare medicinal plant Semiliquidambar cathayensis.

An extensive phytochemical investigation on the rare medicinal plant Semiliquidambar cathayensis (family: Hamamelidaceae) led to the isolation of four new (1-4, named semiliquidacids A-D, respectively) and 25 related known pentacyclic triterpenoids. The new structures with absolute configurations were elucidated by spectroscopic methods, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analysis. Compound 1 represents the first naturally occurring ursane-type triterpenoid featuring an uncommon C-25 formyl group. Compound 4 and oleanolic acid (13) exhibited remarkable inhibitory effects against the ATP-citrate lyase (ACL, an emerging drug target for hyperlipidemia and related metabolic disorders) with IC50 values of 6.5 and 11.9 µM, respectively. The molecular interaction and binding mode between the bioactive triterpenoids and ACL were elaborated by conducting a molecular docking study. Meanwhile, the chemotaxonomic significance of the isolated triterpenoids has been briefly discussed.

Myasthenia gravis with tongue muscle atrophy: A case series.

Here, we presented 6 patients who were admitted to our institution and diagnosed as myasthenia gravis (MG) with tongue muscle atrophy. All these 6 patients developed symptoms of bulbar muscle weakness in acetylcholine receptor antibodies positive MG (AChR-MG) (3/6), muscle-specific receptor tyrosine kinase antibodies positive MG (MuSK-MG) (1/6), and sero-negative MG (2/6). Most of patients had "triple-furrowed" tongue except for patient 2 with irregular atrophy of tongue muscle. Tongue muscle atrophy occurs in patients with MuSK-MG, AChR-MG, and sero-negative MG. Atrophied tongue muscles of five patients with MG were reversible after immunotherapy.

MODELS: a six-step framework for developing an infectious disease model.

Since the COVID-19 pandemic began, a plethora of modeling studies related to COVID-19 have been released. While some models stand out due to their innovative approaches, others are flawed in their methodology. To assist novices, frontline healthcare workers, and public health policymakers in navigating the complex landscape of these models, we introduced a structured framework named MODELS. This framework is designed to detail the essential steps and considerations for creating a dependable epidemic model, offering direction to researchers engaged in epidemic modeling endeavors.

Isolated Binary Fe-Ni Metal-Nitrogen Sites Anchored on Porous Carbon Nanosheets for Efficient Oxygen Electrocatalysis through High-Temperature Gas-Migration Strategy.

Atomically dispersed dual-site catalysts can regulate multiple reaction processes and provide synergistic functions based on diverse molecules and their interfaces. However, how to synthesize and stabilize dual-site single-atom catalysts (DACs) is confronted with challenges. Herein, we report a facile high-temperature gas-migration strategy to synthesize Fe-Ni DACs on nitrogen-doped carbon nanosheets (FeNiSAs/NC). FeNiSAs/NC exhibits a high half-wave potential (0.88 V) for the oxygen reduction reaction (ORR) and a low overpotential of 410 mV at 10 mA cm-2 for the oxygen evolution reaction (OER). As an air electrode for Zn-air batteries (ZABs), it shows better performances in aqueous ZABs and excellent stability and flexibility in solid-state ZABs. The high specific surface area (1687.32 m2/g) of FeNiSAs/NC is conducive to electron transport. Density functional theory (DFT) reveals that the Fe sites are the active center, and Ni sites can significantly optimize the free energy of the oxygen-containing intermediate state on Fe sites, contributing to the improvement of ORR and the corresponding OER activities. This work can provide guidance for the rational design of DACs and understand the structure-activity relationship of SACs with multiple active sites for electrocatalytic energy conversion.

Trends in Respiratory Infectious Pathogens in Children Under the Age of 14 - Xiamen City, Fujian Province, China, 2017-2023.

What is already known about this topic?: Respiratory infections pose a significant burden on public health. Despite recent outbreaks occurring in various locations, there is limited information available on the prevalence trends of multiple common respiratory pathogens in China beyond 2022. What is added by this report?: A retrospective analysis was conducted on respiratory pathogen infections in a Xiamen hospital over a seven-year period. The analysis revealed fluctuating trends, with the number of infections for certain viruses initially decreasing after 2019, only to rebound to previous or higher levels. Recently, there has been an observed collective increase in positive cases for certain pathogens. What are the implications for public health practice?: The study improves understanding of respiratory pathogens, primarily in Xiamen, with potential implications for the improvement of strategies for the prevention and management of respiratory infectious diseases.

Recent advances in harnessing biological macromolecules for wound management: A review.

Wound dressings (WDs) are an essential component of wound management and serve as an artificial barrier to isolate the injured site from the external environment, thereby helping to prevent exogenous infections and supporting healing. However, maintaining a moist wound environment, providing protection from infection, good biocompatibility, and allowing for gas exchange, remain a challenge in device design. Functional wound dressings (FWDs) prepared from hybrid biological macromolecule-based materials can enhance efficacy of these systems for skin wound management. This review aims to provide an overview of the state-of-the-art FWDs within the field of wound management, with a specific focus on hybrid biomaterials, techniques, and applications developed over the past five years. In addition, we highlight the incorporation of biological macromolecules in WDs, the emergence of smart WDs, and discuss the existing challenges and future prospects for the development of advanced WDs.

Enantioselective Ring-Closing Aminomethylamination of Allylic Aminodienes with Aminals Triggered by C-N Bond Metathesis.

A conceptually novel strategy utilizing a cyclopalladated complex as an electrophile to activate the C-N bond for the C-N bond metathesis between allylamines and aminals is developed, which enables an efficient ring-closing aminomethylamination of allylic aminodienes and aminals. The reaction proceeds under mild reaction conditions and displays a remarkable scope. Utilizing a modified Trost-type diphosphine as the ligand, this method enables the efficient synthesis of 5-10-membered aminoallylated chiral N-heterocycles in good yields with high enantiomeric excess values.

Parallel edge extraction operators on chip speed up photonic convolutional neural networks.

We experimentally establish a 3 × 3 cross-shaped micro-ring resonator (MRR) array-based photonic multiplexing architecture relying on silicon photonics to achieve parallel edge extraction operations in images for photonic convolution neural networks. The main mathematical operations involved are convolution. Precisely, a faster convolutional calculation speed of up to four times is achieved by extracting four feature maps simultaneously with the same photonic hardware's structure and power consumption, where a maximum computility of 0.742 TOPS at an energy cost of 48.6 mW and a convolution accuracy of 95.1% is achieved in an MRR array chip. In particular, our experimental results reveal that this system using parallel edge extraction operators instead of universal operators can improve the imaging recognition accuracy for CIFAR-10 dataset by 6.2% within the same computing time, reaching a maximum of 78.7%. This work presents high scalability and efficiency of parallel edge extraction chips, furnishing a novel, to the best of our knowledge, approach to boost photonic computing speed.

Carbopol 940-based hydrogels loading synergistic combination of quercetin and luteolin from the herb Euphorbia humifusa to promote Staphylococcus aureus infected wound healing.

With the increasing prevalence of Staphylococcus aureus infections, rapid emergence of drug resistance and the slow healing of infected wounds, developing an efficient antibiotic-free multifunctional wound dressing for inhibiting S. aureus and simultaneously facilitating wound healing have become a huge challenge. Due to their excellent biocompatibility and biodegradability, some carbopol hydrogels based on plant extracts or purified compounds have already been applied in wound healing treatment. In China, Euphorbia humifusa Willd. (EuH) has been traditionally used as a medicine and food homologous medicine for the treatment of furuncles and carbuncles mainly caused by S. aureus infection. In an earlier study, EuH-originated flavonoids quercetin (QU) and luteolin (LU) could serve as a potential source for anti-S. aureus drug discovery when used in synergy. However, the in vivo effects of QU and LU on S. aureus-infected wound healing are still unknown. In this study, we found a series of Carbopol 940-based hydrogels loading QU and LU in combination could disinfect S. aureus and also could promote wound healing. In the full-thickness skin defect mouse model infected with S. aureus, the wound contraction ratio, bacterial burden, skin hyperplasia and inflammation score, as well as collagen deposition and blood vessels were then investigated. The results indicate that the optimized QL2 [QU (32 µg mL-1)-LU (8 µg mL-1)] hydrogel with biocompatibility significantly promoted S. aureus-infected wound healing through anti-infection, anti-inflammation, collagen deposition, and angiogenesis, revealing it as a promising alternative for infected wound repair.

Modulating the Electronic States of Pt Nanoparticles on Reducible Metal-Organic Frameworks for Boosting the Oxidation of Volatile Organic Compounds.

The adsorption and activation of pollutant molecules and oxygen play a critical role in the oxidation reaction of volatile organic compounds (VOCs). In this study, superior adsorption and activation ability was achieved by modulating the interaction between Pt nanoparticles (NPs) and UiO-66 (U6) through the spatial position effect. Pt@U6 exhibits excellent activity in toluene, acetone, propane, and aldehyde oxidation reactions. Spectroscopic studies, 16O2/18O2 kinetic isotopic experiments, and density functional theory (DFT) results jointly reveal that the encapsulated Pt NPs of Pt@U6 possess higher electron density and d-band center, which is conducive for the adsorption and dissociation of oxygen. The toluene oxidation reaction and DFT results indicate that Pt@U6 is more favorable to activate the C-H of toluene and the C═C of maleic anhydride, while Pt/U6 with lower electron density and d-band center exhibits a higher oxygen dissociation temperature and higher reactant activation energy barriers. This study provides a deep insight into the architecture-performance relation of Pt-based catalysts for the catalytic oxidation of VOCs.

Computational Modeling of Bone Fracture Healing Under Different Initial Conditions and Mechanical Load.

OBJECTIVE: Computational model of bone healing can replace animal experiments to study the parameters affecting the bone healing process, thus reducing the damage to experimental animals and saving a lot of time. We propose a computational model for continuous simulation of four phases of bone healing to study the effects of mechanical environmental and biological factors, including initial conditions at the fracture site, mechanical stimulus loading, and vascular growth rate. METHODS: A finite element model of mechanobiological fracture healing containing several pre-determined variables was developed for bone healing after fracture in sheep, which included many relevant parameters and biological effects during fracture healing, such as the effects of mechanical environment, blood supply level in the local fracture area, cell migration and diffusion, and resorption effects of fracture healing. The effects of several parameters on indices such as Young's modulus of the callus during bone healing were obtained by simulation. RESULTS: The initial geometry of the healing tissue and mechanical loading had the greatest effect on fracture healing, and different preset values were likely to cause delayed or non-healing fractures. Changed initial tissue properties of the healing tissue showed a nonlinear effect on fracture healing rather than a linear delay or advancement. Parameters related to angiogenesis had a greater effect on fracture healing compared to those related to cell migration. CONCLUSION: This paper quantified the effect of fracture healing pre-determined variables on fracture healing to better understand the application of mechanobiology in fracture healing simulation models and optimization of treatment strategies. SIGNIFICANCE: The importance of initial conditions and loads on fracture healing has been shown to help physicians treat bone nonunion or delayed bone healing after a fracture.

Effects of pressure-controlled ventilation targeting end-inspiratory flow rate on pulmonary complications and inflammation levels in patients undergoing spinal surgery in the prone position: a randomized clinical trial.

BACKGROUND: This study assessed the impact of pressure-controlled ventilation (PCV) focusing on end-inspiratory flow rate on the incidence of postoperative pulmonary complications (PPCs) and inflammation levels in patients undergoing spinal surgery in the prone position. METHODS: A total of 187 patients who underwent posterior spinal surgery were enrolled and randomly divided into 3 groups: 61 in the volume-controlled ventilation (VCV) group (group V), 62 in the PCV-volume-guaranteed (VG) group (group P1), and 64 in the PCV-VG end-expiratory zero flow rate group (group P2). Indicators including tidal volume (VT), peak airway pressure (Ppeak), and dynamic lung compliance (Cdyn) were recorded. The Ppeak, Cdyn, PETCO2, and oxygenation index (PaO2/FiO2) after intubation (T0), after prone position (T1), 60 min after prone position (T2), and after supine position at the end of surgery (T3) of the three groups were collected. RESULTS: In the within-group comparison, compared with T0, Ppeak increased at T1 - 2 in groups V and P1 (P < 0.01), whereas it decreased at T1 - 3 in group P2 (P < 0.01). Cdyn decreased at T1 - 2 and PaO2/FiO2 increased at T1 - 3 in all three groups (P < 0.01), and PaO2/FiO2 increased at T1 - 3 (P < 0.01). Compared with group V, Ppeak decreased at T0 - 3 in group P1 (P < 0.01) and at T1 - 3 in group P2 (P < 0.01), while Cdyn increased at T0 - 3 in groups P1 and P2 (P < 0.01). Compared with group P1, Ppeak was elevated at T0 (P < 0.01) and decreased at T1 - 3 (P < 0.05), and Cdyn was elevated at T0 - 3 in group P2 (P < 0.01). The total incidence of PPCs in group P2 was lower than that in group V (P < 0.01). Compared with the preoperative period, serum interleukin 6 (IL-6) and C-reactive protein (CRP) levels were increased at 24 and 72 h after surgery in group V (P < 0.01), whereas that was increased at 24 h after surgery in group P1 and group P2 (P < 0.01). Compared with group V, serum IL-6 and CRP levels were reduced at 24 h after surgery in groups P1 and P2 (P < 0.01 or < 0.05). CONCLUSION: In patients undergoing spinal surgery in the prone position, PCV-VG targeting an end-inspiratory zero flow rate lowers the incidence of PPCs and inflammation levels.