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Thrombosis and infection are two major complications associated with central venous catheters (CVCs), which significantly contribute to morbidity and mortality. Antifouling coating strategies currently represent an efficient approach for addressing such complications. However, existing antifouling coatings have limitations in terms of both duration and effectiveness. Herein, we propose a durable zwitterionic polymer armor for catheters. This armor is realized by pre-coating with a robust phenol-polyamine film inspired by insect sclerotization, followed by grafting of poly-2-methacryloyloxyethyl phosphorylcholine (pMPC) via in-situ radical polymerization. The resulting pMPC coating armor exhibits super-hydrophilicity, thereby forming a highly hydrated shell that effectively prevents bacterial adhesion and inhibits the adsorption and activation of fibrinogen and platelets in vitro. In practical applications, the armored catheters significantly reduced inflammation and prevented biofilm formation in a rat subcutaneous infection model, as well as inhibited thrombus formation in a rabbit jugular vein model. Overall, our robust zwitterionic polymer coating presents a promising solution for reducing infections and thrombosis associated with vascular catheters.

Abstract Worldwide, skin cancer prevalence necessitates accurate diagnosis to alleviate public health burdens. Although the application of artificial intelligence in image analysis and pattern recognition has improved the accuracy and efficiency of early skin cancer diagnosis, existing supervised learning methods are limited due to their reliance on a large amount of labeled data. To overcome the limitations of data labeling and enhance the performance of diagnostic models, this study proposes a semi-supervised skin cancer diagnostic model based on Self-feedback Threshold Focal Learning (STFL), capable of utilizing partial labeled and a large scale of unlabeled medical images for training models in unseen scenarios. The proposed model dynamically adjusts the selection threshold of unlabeled samples during training, effectively filtering reliable unlabeled samples and using focal learning to mitigate the impact of class imbalance in further training. The study is experimentally validated on the HAM10000 dataset, which includes images of various types of skin lesions, with experiments conducted across different scales of labeled samples. With just 500 annotated samples, the model demonstrates robust performance (0.77 accuracy, 0.6408 Kappa, 0.77 recall, 0.7426 precision, and 0.7462 F1-score), showcasing its efficiency with limited labeled data. Further, comprehensive testing validates the semi-supervised model’s significant advancements in diagnostic accuracy and efficiency, underscoring the value of integrating unlabeled data. This model offers a new perspective on medical image processing and contributes robust scientific support for the early diagnosis and treatment of skin cancer.

Summary: Universal coatings with versatile surface adhesion, good mechanochemical robustness, and the capacity for secondary modification are of great scientific interest. However, incorporating these advantages into a system is still a great challenge. Here, we report a series of catechol-decorated polyallylamines (CPAs), denoted as pseudo-Mytilus edulis foot protein 5 (pseudo-Mefp-5), that mimic not only the catechol and amine groups but also the backbone of Mefp-5. CPAs can fabricate highly adhesive, robust, multifunctional polyCPA (PCPA) coatings based on synergetic catechol-polyamine chemistry as universal building blocks. Due to the interpenetrating entangled network architectures, these coatings exhibit high chemical robustness against harsh conditions (HCl, pH 1; NaOH, pH 14; H2O2, 30%), good mechanical robustness, and wear resistance. In addition, PCPA coatings provide abundant grafting sites, enabling the fabrication of various functional surfaces through secondary modification. Furthermore, the versatility, multifaceted robustness, and scalability of PCPA coatings indicate their great potential for surface engineering, especially for withstanding harsh conditions in multipurpose biomedical applications.

Thrombus formation and tissue embedding significantly impair the clinical efficacy and retrievability of temporary interventional medical devices. Herein, we report an insect sclerotization-inspired antifouling armor for tailoring temporary interventional devices with durable resistance to protein adsorption and the following protein-mediated complications. By mimicking the phenol-polyamine chemistry assisted by phenol oxidases during sclerotization, we develop a facile one-step method to crosslink bovine serum albumin (BSA) with oxidized hydrocaffeic acid (HCA), resulting in a stable and universal BSA@HCA armor. Furthermore, the surface of the BSA@HCA armor, enriched with carboxyl groups, supports the secondary grafting of polyethylene glycol (PEG), further enhancing both its antifouling performance and durability. The synergy of robustly immobilized BSA and covalently grafted PEG provide potent resistance to the adhesion of proteins, platelets, and vascular cells in vitro. In ex vivo blood circulation experiment, the armored surface reduces thrombus formation by 95 %. Moreover, the antifouling armor retained over 60 % of its fouling resistance after 28 days of immersion in PBS. Overall, our armor engineering strategy presents a promising solution for enhancing the antifouling properties and clinical performance of temporary interventional medical devices.

Proteins, cells and bacteria adhering to the surface of medical devices can lead to thrombosis and infection, resulting in significant clinical mortality. Here, we report a zwitterionic polymers-armored amyloid-like protein surface engineering strategy we called as “armored-tank” strategy for dual functionalization of medical devices. The “armored-tank” strategy is realized by decoration of partially conformational transformed LZM (PCTL) assembly through oxidant-mediated process, followed by armoring with super-hydrophilic poly-2-methacryloyloxyethyl phosphorylcholine (pMPC). The outer armor of the “armored-tank” shows potent and durable zone defense against fibrinogen, platelet and bacteria adhesion, leading to long-term antithrombogenic properties over 14 days in vivo without anticoagulation. Additionally, the “fired” PCTL from “armored-tank” actively and effectively kills both Gram-positive and Gram-negative bacterial over 30 days as a supplement to the lacking bactericidal functions of passive outer armor. Overall, this “armored-tank” surface engineering strategy serves as a promising solution for preventing biofouling and thrombotic occlusion of medical devices.

Abstract Universal protein coatings have recently gained wide interest in medical applications due to their biocompatibility and ease of fabrication. However, the challenge persists in protein activity preservation, significantly complicating the functional design of these coatings. Herein, an active dual‐protein surface engineering strategy assisted by a facile stepwise protein–protein interactions assembly (SPPIA) method for catheters to reduce clot formation and infection is proposed. This strategy is realized first by the partial oxidation of bovine serum albumin (BSA) and lysozyme (LZM) for creating stable nucleation platforms via hydrophobic interaction, followed by the assembly of nonoxidized BSA (pI, the isoelectric point, ≈4.7) and LZM (pI ≈11) through electrostatic interaction owing to their opposite charge under neutral conditions. The SPPIA method effectively preserves the conformation and functionality of both BSA and LZM, thus endowing the resultant coating with potent antithrombotic and bactericidal properties. Furthermore, the stable nucleation platform ensures the adhesion and durability of the coating, resisting thrombosis and bacterial proliferation even after 15 days of PBS immersion. Overall, the SPPIA approach not only provides a new strategy for the fabrication of active protein coatings but also shows promise for the surface engineering technology of catheters.

Abstract Background Previously, a novel lamprey immune protein (LIP) was identified, which plays an important role in immunity and the regulation of growth and development in lampreys. However, the mechanism of how LIP regulates growth and development remains unclear. Methods In this study, a zebrafish model of LIP overexpression was established by delivering a transgenic plasmid to the fertilized egg. The biological function of LIP was explored in vivo through phenotypic characterization, comparative transcriptome sequencing, and physiological and biochemical analyses. Results LIP caused developmental toxicity in zebrafish, increased embryo mortality and exhibited strong teratogenic, lethal, and developmental inhibitory effects. Comparative transcriptome analysis showed that LIP-induced large-scale cell death by triggering ferroptosis. Furthermore, LIP-induced lipid peroxidation and caused pericardial edema. Direct inhibition of acsl4a and tfr1a, or silencing of acsl4a and tfr1a with specific siRNA suppressed ferroptosis and pericardial edema. Conclusions Taken together, we confirmed that LIP can participate in growth and development via the regulation of lipid peroxidation and ferroptosis. This lays the foundation for future studies on the function of LIP in lampreys. Video Abstract

Ma et al characterise differentially expressed miRNAs in Lamprey upon bacterial infection. They identify miR-4561 as being decreased after infection and show that it targets the 3′UTR of the mRNA encoding lamprey immune protein (LIP) involved in lamprey innate immunity and regulates survival in lamprey embryos.

Integration of two or more biomolecules with synergetic and complementary effects on a material surface can help to obtain multi-functions for various biomedical applications. However, the amounts of biomolecules integrated and their physiological functions are compromised due to the limited surface anchoring sites. Herein, we propose a novel concept of film engineering strategy “from surface to bulk synergetic modification”. This new concept is realized by employing the surface amine groups of plasma polymerized allylamine (PPAm) film for grafting a molecule e.g., thrombin inhibitor, bivalirudin (BVLD), meanwhile its bulk amine groups is used as a universal depot for storing and releasing therapeutic nitric oxide (NO) gas as supplement to the functions of BVLD. It is demonstrated that such a “from surface to bulk synergetic modification” film engineering can impart the modified-substrates with anti-platelet and anti-coagulant dual functions, giving rise to a highly endothelium-mimetic thromboresistant property. We believe that our research provides a very promising strategy to deliver multifunctional surface versatilely that require NO release in combination with other properties, which will find broad biomedical applications in blood-contacting devices, and et al. Moreover, it also provides a brand-new film engineering strategy for tailoring surface multi-functionalities of a wide range of materials. Keywords: Surface chemistry, Amine-bearing coating, Synergic modification, Biomolecule grafting, Nitric oxide loading

Diabetic retinal image classification aims to conduct diabetic retinopathy automatically diagnosing, which has achieved considerable improvement by deep learning models. However, these methods all rely on sufficient network training by large scale annotated data, which is very labor-expensive in medical image labeling. Aiming to overcome these drawbacks, this paper focuses on embedding self-supervised framework into unsupervised deep learning architecture. Specifically, we propose a Self-supervised Fuzzy Clustering Network (SFCN) by a feature learning module, reconstruction module, and a fuzzy self-supervision module. The feature learning and reconstruction modules ensure the representative ability of the network, and fuzzy self-supervision module is in charge of further providing the training direction for the whole network. Furthermore, three losses of reconstruction, self-supervision, and fuzzy supervision jointly optimize the SFCN under an unsupervised manner. To evaluate the effectiveness of the proposed method, we implement the network on three widely used retinal image datasets, which results demonstrate the satisfied performance on unsupervised retinal image classification task.

The popularity of Internet applications has made communication privacy an increasingly important security requirement. As an important aspect of privacy, anonymity ensures that a subject may use resources or services without disclosing user identity or corresponding relationships. Since the seminal work by Chaum for anonymous communication, many different anonymous communication systems, and anonymous protocols have been developed and investigated extensively. In recent years, anonymous communication systems have evolved from academic tools used by specialists to mass-market software used by millions of ordinary people. How to evaluate and quantify the anonymity that different anonymous communication systems can offer has been a new focus. Though some efforts have been made on anonymity metrics and measuring techniques, systematic research on measuring anonymity of anonymous communication systems is still needed. In this paper, we give a comprehensive overview of state-of-the-art research on measuring anonymity. We first summarize the anonymous mechanisms applied by different anonymous systems. We then introduce the formalization of the notion of anonymity for measuring the anonymity degree. Further, metrics based on various theories and approaches are reviewed. We particularly elaborate on the metrics based on information theory as a separate section because of its popularity and multiple branches. The metrics based on information entropy is probably of the greatest interest.

Abstract Endothelium can secrete vasoactive mediators and produce specific extracellular matrix, which contribute jointly to the thromboresistance and regulation of vascular cell behaviors. From a bionic point of view, introducing endothelium‐like functions onto cardiovascular stents represents the most effective means to improve hemocompatibility and reduce late stent restenosis. However, current surface strategies for vascular stents still have limitations, like the lack of multifunctionality, especially the monotony in endothelial‐mimic functions. Herein, a layer‐by‐layer grafting strategy to create endothelium‐like dual‐functional surface on cardiovascular scaffolds is reported. Typically, a nitric oxide (NO, vasoactive mediator)‐generating compound and an endothelial polysaccharide matrix molecule hyaluronan (HA) are sequentially immobilized on allylamine‐plasma‐deposited stents through aqueous amidation. In this case, the stents could be well‐engineered with dual endothelial functions capable of remote and close‐range regulation of the vascular microenvironment. The synergy of NO and endothelial glycocalyx molecules leads to efficient antithrombosis, smooth muscle cell (SMC) inhibition, and perfect endothelial cell (EC)‐compatibility of the stents in vitro. Moreover, the dual‐functional stents show efficient antithrombogenesis ex vivo, rapid endothelialization, and long‐term prevention of restenosis in vivo. Therefore, this study will provide new solutions for not only multicomponent surface functionalization but also the bioengineering of endothelium‐mimic vascular scaffolds with improved clinical outcomes.

Soil aggregates are the material basis of soil structure and important carriers of nutrients. Long-term application of organic and inorganic fertilizers can affect the composition of soil aggregates to varying degrees, which in turn affects the distribution and storage of soil nutrients. We report the results of a 15-year long-term field-based test of aeolian sandy soil and used the wet sieve method to analyze the stability of water-stable aggregates, as well as the distribution characteristics of nutrients in different particle size aggregates. Our results show that long-term application of organic fertilizer (M3) and combined organic–inorganic treatments (NPK1-M1, NPK1-M2, and NPK1-M3) help to increase the amount of organic carbon, inorganic carbon, and cation exchange in the macro-aggregates, and the improvement rates are 92–103%, 8–28%, and 74–85%, respectively. The organic content of the fertilizers also promotes the formation of macro-aggregates, and the stability of aggregates increase from 0.24 to 0.45. In contrast, the application of inorganic fertilizers (NPK1, NPK2, and NPK3) has no marked effect on the formation and stability of macro-aggregates; the application of inorganic fertilizers can merely maintain the organic carbon content of the soil. Correlation analysis shows that the application of organic fertilizers and chemical (inorganic) fertilizers containing phosphorus and potassium can markedly increase the content and reserves of available phosphorus and potassium across all aggregate sizes, and there is a significant positive correlation between these parameters and the amount of applied fertilizer (p < 0.05). Aggregates of various sizes in aeolian sandy soils in arid areas have the potential for greater nutrient storage. Therefore, organic fertilizers can be used in the agricultural production process to improve soil structure and fertility.

A reduced polyoxometalate-based organo-metallophosphate (MOPO) framework formulated as [Co4(PO4)(C7H8N4)6] (PWVI10WV2O40) (Co-PO4-PW12) with an ultra-high CO production rate of 13 676 µmol g-1 h-1 has been presented through photocatalytic CO2 reduction investigations. [ABSTRACT FROM AUTHOR]

Land cover products provide critical information for monitoring and analyzing land surface changes. However, notable disagreement and incompatible classification systems among existing land cover products bring challenges in using them. Here, we developed a hierarchical International Geosphere-Biosphere Programme (IGBP) classification system and integrated four widely used land cover products (i.e., MODIS-IGBP, ESA-CCI, GlobeLand30, and GLC_FCS30) based on their accuracy against a collection of global reference samples. We generated a hybrid global annual land cover product (HYBMAP) with ~1 km (1/120°, 30″) spatial resolution from 2000 to 2020. The HYBMAP integrates information from the four products of high- and medium-resolution and reduces the disagreement between them by up to 20.1%. The overall accuracy of the HYBMAP is 75.5%, which is higher than the best of the four products (MODIS-IGBP, 70.9%). HYBMAP also integrates the temporal change information from the four products and identifies a faster growth of built-up lands. The HYBMAP provides more consistent and reliable global land cover time series data for global change research. It is free to access at https://doi.org/10.5281/zenodo.10488191.

ABSTRACT It is essential for aerobic organisms to maintain the homeostasis of intracellular reactive oxygen species (ROS) for survival and adaptation to the environment. In line with other eukaryotes, the catalase of Neurospora crassa is an important enzyme for clearing ROS, and its expression is tightly regulated by the growth phase and various oxidative stresses. Our study reveals that, in N. crassa, histone deacetylase 2 (HDA-2) and its catalytic activity positively regulate the expression of the catalase-3 (cat-3) gene. HDA-2, SIF-2, and SNT-1 may form a subcomplex with such a regulation role. As expected, deletion of HDA-2 or SIF-2 subunit increased acetylation levels of histone H4, indicating that loss of HDA-2 complex fails to deacetylate H4 at the cat-3 locus. Furthermore, loss of HDA-2 or its catalytic activity led to dramatic decreases of TFIIB and RNA polymerase II (RNAP II) recruitment at the cat-3 locus and also resulted in high deposition of H2A.Z at the promoter and transcription start site (TSS) regions of the cat-3 gene. Collectively, this study strongly demonstrates that the HDA-2-containing complex activates the transcription of the cat-3 gene by facilitating preinitiation complex (PIC) assembly and antagonizing the inhibition of H2A.Z at the cat-3 locus through H4 acetylation. IMPORTANCE Clearance of reactive oxygen species (ROS) is critical to the survival of aerobic organisms. In the model filamentous fungus Neurospora crassa, catalase-3 (cat-3) expression is activated in response to H2O2-induced ROS stress. We found that histone deacetylase 2 (HDA-2) positively regulates cat-3 transcription in N. crassa; this is widely divergent from the classical repressive role of most histone deacetylases. Like HDA-2, the SIF-2 or SNT-1 subunit of HDA-2-containing complex plays a positive role in cat-3 transcription. Furthermore, we also found that HDA-2-containing complex provides an appropriate chromatin environment to facilitate PIC assembly and to antagonize the inhibition role of H2A.Z at the cat-3 locus through H4 acetylation. Taken together, our results establish a mechanism for how the HDA-2-containing complex regulates transcription of the cat-3 gene in N. crassa.

The mechanical properties of gas-containing coal and rock mass play important roles in controlling the occurrence and development of coal and gas outbursts. The gradual increase in mining depth will change the failure mechanism of gas-containing coal and rock mass. In order to further study the failure mechanism of gas-containing coal and rock mass, samples were taken from the gas-containing coal seam in the Wuhushan Coal Mine of the Wuhai Mining area of China. The mechanical parameters of coal samples during the failure process under different gas pressure conditions were measured and analyzed with the SAW-2000 rock mechanics testing machine, the gas-containing coal uniaxial compression device and inflation system. Meanwhile, the failure process and mechanical parameters of coal samples under different gas pressure were simulated by RFPA2D gas plate numerical simulation software. The results show that with increasing gas pressure in the coal there is decrease in Compressive strength, Elastic modulus, Strain, Peak strength and Bearing capacity and increase in Poisson’s ratio. When the failure state appears in the coal, the cracks are longer and wider, more random cracks are genareted, and the damage degree of the coal is greater. The numerical analysis’ results are in good agreement with experimental results. The research results are applicable to the gas bearing coal with the same or similar gas geological conditions. The tests can be carried out repeatedly and reasonable results can be obtained according to the physical and mechanical parameters of the actual coal seam and the occurrence of gas. On this basis, physical experiments and numerical simulations of triaxial compression can also be carried out to further study the mechanical characteristics of deformation and the failure of gas-containing coal under gas pressure and provide technical support for revealing the mechanism of coal and gas outbursts.

CFRP materials are widely used in special environments, and it has excellent mechanical properties. However, CFRP processing is very difficult, especially in the process of using traditional cutting methods, due to its heterogeneity and anisotropy. In this work, based on the failure mechanism of CFRP materials, we studied the cutting mechanism of the cutters in milling processing, modeled and analyzed the milling cutters and processing materials, and conducted orthogonal milling experiments of CFRP composite materials. Based on the experimental data, the influence of different machining parameters on the cutting force was studied, and the relationship between the influence of different cutting methods on the cutting stress and cutting heat on the life of the milling tool was obtained. According to the angle between the fiber orientation and the cutting edge of the cutting edge, the cutting behavior of single fiber and CFRP unidirectional laminate is classified. The failure modes of CFRP materials under different processing behaviors are predicted and analyzed, and the theoretical model is simulated by the finite element method. The CFRP milling process and failure process are theoretically analyzed, and the milling failure process and failure forms are summarized. Through the finite element simulation of the failure process and the section observation under the scanning electron microscope, the cutting mechanism of the CFRP material is analyzed, which provides a reference for optimizing the milling parameters and optimizing the mechanism.

A reduced polyoxometalate-based organo-metallophosphate (MOPO) framework formulated as [Co4(PO4)(C7H8N4)6] (PWVI10WV2O40) (Co-PO4-PW12) with an ultra-high CO production rate of 13 676 µmol g-1 h-1 has been presented through photocatalytic CO2 reduction investigations. [ABSTRACT FROM AUTHOR]

Background The phenomenon of "no referral" still exists against the backdrop of implementing the hierarchical medical system, which has been preliminarily constructed in China. Most existing studies on addressing this phenomenon are mostly from the perspective of hospital management policies, ignoring the role of doctors as "health gatekeepers" in making decisions during the hierarchical diagnosis and treatment process. Objective To investigate the influence of personal, institutional, environmental, and policy factors on the willingness of physicians in county hospitals to refer patients with common diseases to lower level of institutions from physicians' perspective. Methods This study was conducted from July to August 2021. By use of region-based stratified and convenience sampling, seven county-level people's hospitals were selected as settings from eastern, central and western China. By use of cluster sampling, physicians (n=142) in internal medical departments were selected from the above-mentioned hospitals to attend an online (through the WJX.cn platform) or off-line (hospital) questionnaire survey to understand their willingness to refer patients with a common illness to lower level institutions, and personal, institutional, environmental, and policy factors associated with their willingness during a consultation described using the scenario simulation method. The survey achieved a response rate of 96.5% (137/142). Binary Logistic regression was used to analyze the effects of personal, institutional, environmental, and policy factors on physicians' willingness to refer the patients to a lower level institution. Results The mean score of physicians' willingness to refer the patients to a lower level institution was (9.92±2.20). Fifty-six physicians (40.9%) had higher level of willingness to conduct downward referrals. Education level, awareness level of referrals, and frequency of communication of referrals between higher and lower level institutions were associated with scores of physicians' willingness to conduct downward referrals (P