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Abstract Owing to the ability to parallel manipulate micro-objects, dynamic holographic optical tweezers (HOTs) are widely used for assembly and patterning of particles or cells. However, for simultaneous control of large-scale targets, potential collisions could lead to defects in the formed patterns. Herein we introduce the artificial potential field (APF) to develop dynamic HOTs that enable collision-avoidance micro-manipulation. By eliminating collision risks among particles, this method can maximize the degree of parallelism in multi-particle transport, and it permits the implementation of the Hungarian algorithm for matching the particles with their target sites in a minimal pathway. In proof-of-concept experiments, we employ APF-empowered dynamic HOTs to achieve direct assembly of a defect-free 8 × 8 array of microbeads, which starts from random initial positions. We further demonstrate successive flexible transformations of a 7 × 7 microbead array, by regulating its tilt angle and inter-particle spacing distances with a minimalist path. We anticipate that the proposed method will become a versatile tool to open up new possibilities for parallel optical micromanipulation tasks in a variety of fields.

Multifunctional therapeutics have emerged as a solution to the constraints imposed by drugs with singular or insufficient therapeutic effects. The primary challenge is to integrate diverse pharmacophores within a single-molecule framework. To address this, we introduced DeepSA, a novel edit-based generative framework that utilizes deep simulated annealing for the modification of articaine, a well-known local anesthetic. DeepSA integrates deep neural networks into metaheuristics, effectively constraining molecular space during compound generation. This framework employs a sophisticated objective function that accounts for scaffold preservation, anti-inflammatory properties, and covalent constraints. Through a sequence of local editing to navigate the molecular space, DeepSA successfully identified AT-17, a derivative exhibiting potent analgesic properties and significant anti-inflammatory activity in various animal models. Mechanistic insights into AT-17 revealed its dual mode of action: selective inhibition of NaV1.7 and 1.8 channels, contributing to its prolonged local anesthetic effects, and suppression of inflammatory mediators via modulation of the NLRP3 inflammasome pathway. These findings not only highlight the efficacy of AT-17 as a multifunctional drug candidate but also highlight the potential of DeepSA in facilitating AI-enhanced drug discovery, particularly within stringent chemical constraints.

Background Although the roles of PD-L1 in promoting tumor escape from immunosurveillance have been extensively addressed, its non-immune effects on tumor cells remain unclear.Methods The spatial heterogeneity of PD-L1 staining in human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) tissues was identified by immunohistochemistry. Three-dimensional (3D) specific cell-led invasion assay and 3D cancer spheroid model were used to investigate the roles of PD-L1hileader cells in collective invasion. The impact of M1 macrophages on specific PD-L1 expression in leader cells and its mechanisms were further studied. Finally, the effect of combination therapy of anti-PD-L1 and CDK4 inhibitor on HPV-positive tumors were evaluated on a mice model.Results Here, we observed a distinctive marginal pattern of PD-L1 expression in HPV-positive HNSCC tissues. By mimicking this spatial pattern of PD-L1 expression in the 3D invasion assay, we found that PD-L1hi cells led the tumor collective invasion. M1 macrophages induced specific PD-L1 expression in leader cells, and depletion of macrophages in tumor-bearing mice abrogated PD-L1hileader cells and collective invasion. Mechanistically, TNF-α secreted by M1 macrophages markedly increased the abundance of PD-L1 via CDK4/ubiquitin-specific peptidase 14-mediated deubiquitination of PD-L1. We also found that suppression of CDK4 enhanced the efficacy of anti-PD-L1 therapy in an E6/E7 murine model.Conclusions Our study identified TNF-α/CDK4/ubiquitin-specific peptidase 14-mediated PD-L1 stability as a novel mechanism underlying M1 macrophage-induced PD-L1hileader cells and collective tumor invasion, and highlighted the potential of the combination therapy of anti-PD-L1 and CDK4 inhibitor for HPV-positive HNSCC.

Tinnitus is an auditory phantom percept that affects the perception of sound in the patient’s ears, and the incidence of prolonged tinnitus is as high as ten to fifteen percent. Acupuncture is a unique treatment method in Chinese medicine, and it has great advantages in the treatment of tinnitus. However, tinnitus is a subjective symptom of patients, and there is currently no objective detection method to reflect the improvement effect of acupuncture on tinnitus. We used functional near-infrared spectroscopy (fNIRS) to explore the effect of acupuncture on the cerebral cortex of tinnitus patients. We collected the scores of the tinnitus disorder inventory (THI), tinnitus evaluation questionnaire (TEQ), hamilton anxiety scale (HAMA), and hamilton depression scale (HAMD) of eighteen subjects before and after acupuncture treatment, and the fNIRS signals of these subjects in sound-evoked activity before and after acupuncture treatment. According to the fNIRS detection results of tinnitus patients, acupuncture increased the concentration of oxygenated hemoglobin in the temporal lobe of tinnitus patients, and affected the activation of the auditory cortex. The study may reflect the neural mechanisms of acupuncture treatment for tinnitus and ultimately help to provide an objective evaluation method for the therapeutic effect of acupuncture treatment for tinnitus.

Scattering media, such as biological tissues and turbid liquids, scatter light randomly and introduce several challenges when imaging objects behind them. The transmission matrix (TM) describes the relation between the input and output of a beam transmitted through a medium, which can be used to reconstruct a target located behind a scattering medium. However, the current TM methods cannot easily retrieve the phase distribution of objects inside or behind a scattering medium. In this work, a compressive sensing (CS) method to identify the TM of a scatter contained in an imaging system was investigated. By calibrating the TM, the phase information of the object can be retrieved quantitatively. This method allows one to retrieve multilevel and dynamic phase objects behind different scatters. The influence of the calibration parameters on the reconstruction quality was investigated in detail. The proposed method, featuring noninterference measurements of the TM and exploiting a large field of view, can be used in phase imaging applications.

Light-sheet fluorescence microscopy (LSFM) is a kind of volumetric imaging methodology suited for long term living specimens at high temporal-spatial resolution. A single Airy beam (SAB) light-sheet can extend the field of view of Light-sheet fluorescence microscopy benefiting from its non-diffracting nature, but at the cost of out-of-focus background and low imaging contrast caused by side lobes illumination. Here, we propose a method to generate a sort of multiple Airy beams (MAB), which are linearly superimposed of multiple single Airy beams with different scale factors. Compared to the SAB light-sheet, the energy of the multiple Airy beams light-sheet is more concentrated on the focal plane of the detection objective, which can improve the imaging contrast and decrease the photodamage effect. Furthermore, we combined the complementary beam subtraction (CBS) strategy to increase the axial resolution, termed as multiple Airy beams-complementary beam subtraction method, which enables the axial resolution of 1.2 μm while keeping the field of view of 450 μm × 450 μm. The effectiveness of the method is demonstrated by imaging of fluorescent beads and aspergillus conidiophores.

Super-resolution structured illumination microscopy (SIM) routinely performs image reconstruction in the frequency domain using an approach termed frequency-domain reconstruction (FDR). Due to multiple Fourier transforms between the spatial and frequency domains, SIM suffers from low reconstruction speed, constraining its applications in real-time, dynamic imaging. To overcome this limitation, we developed a new method for SIM image reconstruction, termed spatial domain reconstruction (SDR). SDR is intrinsically simpler than FDR, does not require Fourier transforms and the theory predicts it to be a rapid image reconstruction method. Results show that SDR reconstructs a super-resolution image 7-fold faster than FDR, producing images that are equal to either FDR or the widely-used FairSIM. We provide a proof-of-principle using mobile fluorescent beads to demonstrate the utility of SDR in imaging moving objects. Consequently, replacement of the FDR approach with SDR significantly enhances SIM as the desired method for live-cell, instant super-resolution imaging. This means that SDR-SIM is a “What You See Is What You Get” approach to super-resolution imaging.

BACKGROUND:Temperature is a key factor influencing the growth and distribution of Taxus chinensis var. mairei, which is of high medicinal value. However, there is little information about the changes in rhizosphere bacterial community of Taxus chinensis var. maire under different temperatures. METHODS:In this study, the rhizosphere bacterial communities of Taxus chinensis var. maire under a series of temperatures [5°C (T5), 15°C (T15), 25°C (T25), 35°C (T35)] were assessed through high-throughput sequencing. And some taxa annotated as Mitochondria were positively correlated with the activity of SOD. RESULTS:Activity of peroxidase (POD) and superoxide dismutase (SOD) were increased and decreased respectively with increasing incubation temperature, showing that SOD may be the dominant reactive oxygen species (ROS) detoxifying enzyme in Taxus chinensis var. maire under low temperature. Taxus chinensis var. maire enriched specific bacterial taxa in rhizosphere under different temperature, and the rhizosphere bacterial diversity decreased with increasing temperature. CONCLUSION:The results indicated that rhizosphere bacteria may play important role for Taxus chinensis var. maire in coping with temperature changes, and the management of rhizosphere bacteria in a potential way to increase the cold resistance of Taxus chinensis var. mairei, thus improving its growth under low temperature and enlarging its habitats.

Taxus chinensis is a rare and endangered shrub, highly sensitive to temperature changes and widely known for its potential in cancer treatment. How gene expression of T. chinensis responds to low temperature is still unknown. To investigate cold response of the genus Taxus, we obtained the transcriptome profiles of T. chinensis grown under normal and low temperature (cold stress, 0°C) conditions using Illumina Miseq sequencing. A transcriptome including 83,963 transcripts and 62,654 genes were assembled from 4.16 Gb of reads data. Comparative transcriptomic analysis identified 2,025 differently expressed (DE) isoforms at p < 0.05, of which 1,437 were up-regulated by cold stress and 588 were down-regulated. Annotation of DE isoforms indicated that transcription factors (TFs) in the MAPK signaling pathway and TF families of NAC, WRKY, bZIP, MYB, and ERF were transcriptionally activated. This might have been caused by the accumulation of secondary messengers, such as reactive oxygen species (ROS) and Ca2+. While accumulation of ROS will have caused damages to cells, our results indicated that to adapt to low temperatures T. chinensis employed a series of mechanisms to minimize these damages. The mechanisms included: (i) cold-enhanced expression of ROS deoxidant systems, such as peroxidase and phospholipid hydroperoxide glutathione peroxidase, to remove ROS. This was further confirmed by analyses showing increased activity of POD, SOD, and CAT under cold stress. (ii) Activation of starch and sucrose metabolism, thiamine metabolism, and purine metabolism by cold-stress to produce metabolites which either protect cell organelles or lower the ROS content in cells. These processes are regulated by ROS signaling, as the “feedback” toward ROS accumulation.

Background: Acupuncture carries the potential risk of transmission of pathogenic microorganisms from the environment to the patient, and from one patient to another. An outbreak of tuberculosis at a private clinic in eastern China was investigated to identify the source of infection, mode of transmission, and risk factors for infection. Methods: A probable case was one who had the onset of unexplained pain, swelling, or abscess in the area of invasive treatment between January 1, 2011 and February 23, 2012. A confirmed case was a probable case with positive laboratory test results for Mycobacterium tuberculosis. Patient history and the frequency of invasive treatment were compared between 56 probable and confirmed cases and 98 controls in a case–control study. Results: Fifty-six of 2561 patients (2.2%) who had visited the clinic developed tuberculosis. The odds ratio (OR) of M. tuberculosis infection increased with the frequency of clinic visits (Chi-square for trend = 28.943, p = 0.000). Multivariate analysis showed that the frequency of acupuncture (Chi-square = 24.258, adjusted p-value = 0.000) and sharing acupuncture needles (Chi-square = 8.936, adjusted p-value = 0.003) were risk factors for M. tuberculosis infection. Thirty-two pus sample and nine sputum sample cultures were M. tuberculosis-positive. Conclusions: This outbreak was caused by acupuncture and was transmitted through sharing acupuncture needles contaminated with M. tuberculosis.

Abstract This study analyzes the impact of public participation on the choice of third-party evaluators' behavior strategies during the service quality supervision process of China's pension public–private partnership project. An evolutionary game model between third-party evaluators and government regulators is developed, wherein the evolution rule of the two sides and public participation’s influence on their behavior under the two different conditions are analyzed, and a numerical simulation is carried out using MATLAB 2016a. It is found that third-party evaluators may choose the false evaluation strategy without public participation because of the inducement of rent-seeking or insufficient government punishment when the regulatory revenue of the government regulatory agencies is less than the regulatory cost. In contrast, in the case of public participation, the true evaluation strategy is chosen with an improvement in the level of public participation or an increase in reputation incentive. This suggests the construction and improvement of a third-party evaluation system, which shows that the construction of the service quality supervision system in China’s pension PPP project has a large operating space.

The processing residue of Pterocarpus erinaceus was used to obtain an ethanol-extract, whose anti-fungal properties and mode of action was investigated using multi-omics principles and gas chromatography-mass spectrometry. The results showed that the decay resistance of the heartwood of Pterocarpus erinaceus was in Grade I; it showed strong decay resistance. The effective concentration of 70% ethanol extract of the heartwood of Pterocarpus erinaceus was 13.8%. It showed high inhibition against Coriolus versicolor and Gloeophyllum trabeum, and the content of the extract was positively correlated with the diameter of the inhibition zone. Transcriptomics analysis showed there were 93 genes differentially expressed in Gloeophyllum trabeum. Among them, 42 genes were up-regulated and 51 genes were down-regulated. These genes were mainly related to oxidoreductase activity, integral components of the membrane, carbohydrate metabolism, lipid metabolism, and other related Gloeophyllum trabeum life activities. In total, 31 substances were separated and observed using GC-MS, and their peak areas accounted for 91.8% of the total peak area. Of these, 16 substances including ketones, esters, amines, alkanes, olefins and aromatic compounds showed a relatively high content. Ketones accounted for the most abundance at 29.1%. These compounds may represent the main active components of antifungal and decay resistance.

The processing residue of Pterocarpus erinaceus was used to obtain an ethanol-extract, whose anti-fungal properties and mode of action was investigated using multi-omics principles and gas chromatography-mass spectrometry. The results showed that the decay resistance of the heartwood of Pterocarpus erinaceus was in Grade I; it showed strong decay resistance. The effective concentration of 70% ethanol extract of the heartwood of Pterocarpus erinaceus was 13.8%. It showed high inhibition against Coriolus versicolor and Gloeophyllum trabeum, and the content of the extract was positively correlated with the diameter of the inhibition zone. Transcriptomics analysis showed there were 93 genes differentially expressed in Gloeophyllum trabeum. Among them, 42 genes were up-regulated and 51 genes were down-regulated. These genes were mainly related to oxidoreductase activity, integral components of the membrane, carbohydrate metabolism, lipid metabolism, and other related Gloeophyllum trabeum life activities. In total, 31 substances were separated and observed using GC-MS, and their peak areas accounted for 91.8% of the total peak area. Of these, 16 substances including ketones, esters, amines, alkanes, olefins and aromatic compounds showed a relatively high content. Ketones accounted for the most abundance at 29.1%. These compounds may represent the main active components of antifungal and decay resistance.

Moso bamboo is an economically and ecologically important nontimber forestry species. Here, the authors analyze 427 genomes collected from 15 representative geographic areas, and identify genes under balancing selection, putative patterns of historic demography, and candidate genes associated with important traits.

Features and relevant services of online social media have been attracting users during the COVID-19 pandemic. Previous studies have shown that college students tend to use social media more frequently than other groups. However, in being affected by social media overload, the social media use behaviors of many college students have been out of their control in terms of their capabilities or cognition. Based on the stressor–strain–outcome (SSO) model and the theory of compensatory internet use (TCIU), we developed a research model to study the causes of social media overload and its impact on college students’ academic performance during the COVID-19 pandemic. A total of 441 valid responses from college students through questionnaires in China are collected via purposive sampling and used in the data analysis. This study conducts PLS-SEM to analyze collected data, finding that boredom proneness is associated with overload (stress), which has a bearing on social media overload (strain) and the reduction in final performance (outcome). Through illustrating the psychological and behavioral conditions that hinder the academic performance of students, this study provides deeper insights into students’ uncontrollable use of social media. Moreover, with respect to the identified antecedents, this study aims to find solutions to mitigate the impact of social media overload resulting from boredom proneness on the academic performance of college students.

The work environment of employees has been greatly affected by the COVID-19 pandemic, and many limitations and risks can be seen until now. In addition to employees in firms, the faculty in colleges and universities also suffer from pressure and face challenges. For the purpose of performance assessment and promotion, the faculty not only needs to teach students, but also assumes the time pressure from academic research. This study discusses the process in which the faculty’s subjective well-being is affected, in an effort to learn about the job demands of the faculty under the work environment with a high level of time pressure, and the effect of these time-related job demands on their psychological health. In this study, 347 valid questionnaires were collected from universities in coastal areas of the Chinese mainland. The results show that time-related job demands have a positive impact on time pressure; time pressure has a negative impact on subjective well-being; and time-related self-efficacy can significantly mediate the relationship among time-related job demands, time pressure, and subjective well-being. On this basis, this study proposes its theoretical and practical implications.

Abstract Background Cellulases are of great significance for full utilization of lignocellulosic biomass. Termites have an efficient ability to degrade cellulose. Heterologous production of the termite-origin cellulases is the first step to realize their industrial applications. The use of P. pastoris for the expression of recombinant proteins has become popular. The endoglucanase from Reticulitermes speratus (RsEG), belonging to glycoside hydrolase family 9 (GHF9), has not been produced in P. pastoris yet. Results A mutant RsEGm (G91A/Y97W/K429A) was successfully overexpressed in P. pastoris. RsEGm, with optimum pH 5.0, was active over the pH range of 4.0 to 9.0, and exhibited superior pH stability over between pH 4.0 and pH 11.0. It displayed the highest activity and good stability at 40 °C, but lost activity quickly at 50 °C. The apparent kinetic parameters of RsEGm against Carboxymethyl Cellulose (CMC) were determined, with K m and V max of 7.6 mg/ml and 5.4 μmol/min•mg respectively. Co2+, Mn2+ and Fe2+ enhanced the activity of RsEGm by 32.0, 19.5 and 11.2% respectively, while Pb2+ and Cu2+ decreased its activity by 19.6 and 12.7% separately. Conclusions RsEGm could be overexpressed in P. pastoris. It was stable between pH 4.0 and pH 11.0, and exhibited higher stability at temperatures ≤ 40 °C. This endoglucanase may have potential to be used in the field of laundry, textile and lignocellulose-based biofuels and chemicals.

The formation of bacterial biofilms has increased the resistance of bacteria to various environmental factors and is tightly associated with many persistent and chronic bacterial infections. Herein we design a strategy conjugating florfenicol, an antibiotic commonly used in the treatment of streptococcus, with the antimicrobial biomaterial, chitosan oligosaccharides. The results demonstrated that the florfenicol-COS conjugate (F-COS) efficiently eradicated the mature Streptococcus hyovaginalis biofilm, apparently inhibiting drug resistance to florfenicol. A quantity of 250 μg/mL F-COS showed effective inhibitory activity against planktonic cells and biofilm of the bacteria, and a 4-fold improvement of the F-COS compared to unmodified florfenicol was observed. Furthermore, the conjugate showed a broad-spectrum activity against both Gram-positive and Gram-negative bacteria. It suggested that F-COS might have a potential for application in the treatment of biofilm-related infections.

Microbial biofilms are considerably more resistant to antibiotics than planktonic cells. It has been reported that chitosan coupling with the aminoglycoside antibiotic streptomycin dramatically disrupted biofilms of several Gram-positive bacteria. This finding suggested the application of the covalent conjugate of antimicrobial natural polysaccharides and antibiotics on anti-infection therapy. However, the underlying molecular mechanism of the chitosan-streptomycin conjugate (CS-Strep) remains unclear and the poor water-solubility of the conjugate might restrict its applications for anti-infection therapy. In this study, we conjugated streptomycin with water-soluble chitosan oligosaccharides (COS). Unlike CS-Strep, the COS-streptomycin conjugate (COS-Strep) barely affected biofilms of tested Gram-positive bacteria. However, COS-Strep efficiently eradicated established biofilms of the Gram-negative pathogen Pseudomonas aeruginosa. This activity of COS-Strep was influenced by the degree of polymerization of chitosan oligosaccharide. The increased susceptibility of P. aeruginosa biofilms to antibiotics after conjugating might be related to the following: Suppression of the activation of MexX-MexY drug efflux pump system induced by streptomycin treatment; and down-regulation of the biosynthesis of biofilm exopolysaccharides. Thus, this work indicated that covalently linking antibiotics to chitosan oligosaccharides was a possible approach for the development of antimicrobial drugs against biofilm-related infections.