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Broad Absorption Line Quasars (BALQSOs) represent a significant phenomenon in the realm of quasar astronomy, displaying distinct blueshifted broad absorption lines. These enigmatic objects serve as invaluable probes for unraveling the intricate structure and evolution of quasars, shedding light on the profound influence exerted by supermassive black holes on galaxy formation. The proliferation of large-scale spectroscopic surveys such as LAMOST (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope), SDSS (the Sloan Digital Sky Survey), and DESI (the Dark Energy Spectroscopic Instrument) has exponentially expanded the repository of quasar spectra at our disposal. In this study, we present an innovative approach to streamline the identification of BALQSOs, leveraging the power of dimensionality reduction and machine-learning algorithms. Our dataset is meticulously curated from the SDSS Data Release 16 (DR16), amalgamating quasar spectra with classification labels sourced from the DR16Q quasar catalog. We employ a diverse array of dimensionality-reduction techniques, including principal component analysis (PCA), t-Distributed stochastic neighbor embedding (t-SNE), locally linear embedding (LLE), and isometric mapping (ISOMAP), to distill the essence of the original spectral data. The resultant low-dimensional representations serve as inputs for a suite of machine-learning classifiers, including the robust XGBoost and Random Forest models. Through rigorous experimentation, we unveil PCA as the most effective dimensionality-reduction methodology, adeptly navigating the intricate balance between dimensionality reduction and preservation of vital spectral information. Notably, the synergistic fusion of PCA with the XGBoost classifier emerges as the pinnacle of efficacy in the BALQSO classification endeavor, boasting impressive accuracy rates of $97.60\%$by 10-cross validation and $96.92\%$on the outer test sample. This study not only introduces a novel machine-learning-based paradigm for quasar classification but also offers invaluable insights transferrable to a myriad of spectral classification challenges pervasive in the realm of astronomy.

Background: Dieulafoy’s lesion (DL) is a rare and important cause of acute nonvariceal upper gastrointestinal bleeding (ANVUGIB), however, there is a lack of clear guidelines focus on the endoscopic hemostasis treatment for DL. Sclerotherapy, as the ANVUGIB guideline recommended endoscopic hemostasis method, is widely used in clinical practice. The aim of this study is to investigate the efficacy of sclerotherapy as the initial treatment for Dieulafoy’s lesion of the upper gastrointestinal tract (UDL). Methods: Patients with UDL who underwent the ANVUGIB standard endoscopic hemostasis between April 2007 and January 2023 were enrolled. The endoscopic therapy method was left to the discretion of the endoscopist. Results: In total, 219 patients were finally obtained, with 74 (33.8%) receiving sclerotherapy and 145 (66.2%) receiving other standard endoscopic therapy. The rebleeding within 30 days was significantly lower in the sclerotherapy group compared to the other standard group (5.8% vs. 16.8%, p= 0.047). There were no significant differences between the two groups in terms of successful hemostasis rate (93.2% vs. 94.5%, p= 0.713), median number of red blood cell transfusions (3.5 vs. 4.0 units, p= 0.257), median hospital stay (8.0 vs. 8.0 days, p= 0.103), transferred to ICU rate (8.1% vs. 6.2%, p= 0.598), the need for embolization or surgery rate (12.2% vs. 9.7%, p= 0.567) and 30-day mortality (0 vs. 2.1%, p= 0.553). In addition, we found no difference in efficacy between sclerotherapy alone and combination (3.1% vs. 8.1%, p= 0.714). Further analysis revealed that thermocoagulation for hemostasis was associated with a higher rate of rebleeding (28.6% vs. 3.1%, p= 0.042) and longer hospital stay (11.5 vs. 7.5 days, p= 0.005) compared to sclerotherapy alone. Conclusion: Sclerotherapy represents an effective endoscopic therapy for both alone and combined use in patients with upper gastrointestinal Dieulafoy’s lesion. Therefore, sclerotherapy could be considered as initial treatment in patients with bleeding of UDL. Graphical Abstract:

Saturated bicyclic amines are increasingly targeted to the pharmaceutical industry as sp3-rich bioisosteres of anilines. Numerous strategies have been established for the preparation of bridgehead aminobicyclics. However, methods to assemble the bridge-amino hydrocarbon skeleton, which serves as a meta-substituted arene bioisostere, are limited. Herein, a general approach to access 2-aminobicyclo[2.1.1]hexanes (aminoBCHs) by titanium-catalyzed formal [2π + 2σ] cycloaddition of bicyclo[1.1.0]butanes and 2-azadienes was developed. Simple derivatization of aminoBCHs leads to various medicinally and agrochemically important analogues.

• A nanoplatform with oxygen self-supplying and heat-sensitizing capabilities is prepared using a simple and cost-effective method. • The nanoplatform can generate oxygen in response to the acidic microenvironment of the biofilm to alleviate its hypoxic state. • Under near-infrared irradiation, the nanoplatform converts oxygen into a significant amount of singlet oxygen and heat to eradicate biofilm. • The nanoplatform remarkably enhances the efficiency of photodynamic therapy in eradicating multidrug-resistant biofilms. Bacterial biofilms, especially those caused by multidrug-resistant bacteria, have emerged as one of the greatest dangers to global public health. The acceleration of antimicrobial resistance to conventional antibiotics and the severe lack of new drugs necessitates the development of novel agents for biofilm eradication. Photodynamic therapy (PDT) is a promising non-antibiotic method for treating bacterial infections. However, its application in biofilm eradication is hampered by the hypoxic microenvironment of biofilms and the physical protection of extracellular polymeric substances. In this study, we develop a composite nanoplatform with oxygen (O 2) self-supplying and heat-sensitizing capabilities to improve the PDT efficacy against biofilms. CaO 2 /ICG@PDA nanoparticles (CIP NPs) are fabricated by combining calcium peroxide (CaO 2) with the photosensitizer indocyanine green (ICG) via electrostatic interactions, followed by coating with polydopamine (PDA). The CIP NPs can gradually generate O 2 in response to the acidic microenvironment of the biofilm, thereby alleviating its hypoxic state. Under near-infrared (NIR) irradiation, the nanoplatform converts O 2 into a significant amount of singlet oxygen (1O 2) and heat to eradicate biofilm. The generated heat enhances the release of O 2 , accelerates the generation of 1O 2 in PDT, increases cell membrane permeability, and increases bacterial sensitivity to 1O 2. This nanoplatform significantly improves the efficacy of PDT in eradicating biofilm-dwelling bacteria without fostering drug resistance. Experiments on biofilm eradication demonstrate that this nanoplatform can eradicate over 99.9999% of methicillin-resistant Staphylococcus aureus (MRSA) biofilms under 5-min NIR irradiation. Notably, these integrated advantages enable the system to promote the healing of MRSA biofilm-infected wounds with negligible toxicity in vivo, indicating great promise for overcoming the obstacles associated with bacterial biofilm eradication. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Post-endoscopic submucosal dissection electrocoagulation syndrome (PEECS) is an uncommon complication after colorectal endoscopic submucosal dissection (ESD). This study aimed to explore the risk factors of PEECS for superficial colorectal lesions based on the latest and consistent diagnostic criteria and to establish a predictive nomogram model. Methods: This retrospective analysis included patients with superficial colorectal lesions who underwent endoscopic submucosal dissection (ESD) between June 2008 and December 2021 in our center. The independent risk factors of PEECS for superficial colorectal lesions were identified using least absolute shrinkage and selection operator (LASSO) logistic regression analysis, as well as univariate analysis and multivariate logistic regression, and derived predictive nomogram model was constructed. Results: Among the 555 patients with superficial colorectal lesions enrolled, PEECS occurred in 45 (8.1%) patients. Multivariate logistic regression revealed that female sex (OR 3.94, P< 0.001), age > 50 years (OR 4.28, P= 0.02), injury to muscle layer (OR 10.38, P< 0.001), non-lifting sign (OR 2.20, P= 0.04) and inadequate bowel preparation (OR 5.61, P< 0.001) were independent risk factors of PEECS for superficial colorectal lesions. A predictive nomogram model was constructed based on the above five predictors. For this model, the area under the receiver operating characteristic (ROC) curve was 0.855, the calibration curve exhibited good consistency between the prediction and the actual observation, and the C-index was confirmed as 0.843 by bootstrap method. Conclusion: Female sex, age > 50 years, injury to muscle layer, non-lifting sign and inadequate bowel preparation were independent risk factors of PEECS for superficial colorectal lesions. The proposed nomogram could accurately predict the risk of PEECS for superficial colorectal lesions. Graphical abstract:

Biofilms formed by pathogenic bacteria present a persistent risk to human health. While the eradication of matured biofilms remains a formidable challenge, delaying or preventing their formation, which is coordinately regulated by quorum sensing (QS), presents a simpler and more advantageous strategy. Quercetin, a naturally occurring compound with anti-QS properties, has the potential to act as an antibiofilm agent. However, it is plagued by certain inherent drawbacks, including poor water solubility and limited bioavailability. Furthermore, solely blocking QS is not enough to prevent biofilm formation because it lacks bactericidal properties. To address these difficulties, we fabricated bi-functional nanoparticles through the co-assembly of quercetin and copper ions in a facile manner. The resulting quercetin/copper nanoparticles (QC NPs) demonstrated minimal cytotoxicity and hemolysis in vitro. In response to the low pH of microenvironments that were populated by bacterial colonies, the QC NPs underwent disassembly to release copper ions and quercetin. The former exterminated bacteria by disrupting the integrity of the cell membrane, while the latter disrupted the processes involved in QS that are responsible for the biofilm by downregulating the expression of specific genes, effectively preventing the formation of biofilms by both Gram-negative Pseudomonas aeruginosaand Gram-positive Staphylococcus aureus. In addition, the QC NPs were integrated into a bacterial cellulose membrane. The composite membrane proved to be highly effective at inhibiting biofilm formation in vitroand demonstrated the ability to reduce inflammatory responses and accelerate the healing of bacteria-infected wounds in vivo. Overall, the bi-functional QC NPs hold great potential for use in addressing the challenges associated with the management of bacterial biofilms.

This paper studies firstly the fault analysis method of valve-side winding single-phase grounding of converter transformer in line-commutated-converter high-voltage direct-current system. One power frequency cycle after fault is divided into 12 time periods according to the valve state, then the 12 time periods of high-voltage bridge faults are classified into 6 types based on the common characteristics, and the 12 time periods of low-voltage (LV) bridge faults are classified into 3 types. For each type of time period, the current flow path is analyzed, the corresponding circuit equation is written. By combining multiple time periods, the expressions of valve-side current and grid-side current are solved. On this basis, the differential current of converter transformer differential protection is derived and the performance of differential protection under valve-side winding single-phase grounding is studied. The research results show that when a single-phase grounding fault occurs in the valve-side winding of the LV bridge converter transformer, the second-harmonic ratio in the differential current is bigger than 15%, so the differential protection refuses to act due to mis-locking. In order to prevent differential protection from failing to act, an improved scheme of converter transformer differential protection is proposed. Through the logic coordination between the zero-sequence current unit and differential protection, the improved scheme can not only reflect various internal faults of converter transformer, but also ensure no action under the inrush current. The effectiveness of the proposed scheme is verified by simulation.

Purpose: Cardiovascular disease is one of the leading causes of mortality in patients with obesity. Metabolically healthy obesity (MHO), in which people do not have metabolic disorders, is a transient state of obesity. However, over the long term, a proportion of individuals with MHO develop metabolic syndrome (MetS). We aimed to investigate the effect of substantial weight loss following bariatric surgery in MHO on carotid intima-media thickness (CIMT) and pulse-wave velocity (PWV), which are independent predictors of subclinical atherosclerosis. Methods: This prospective study included 38 patients (34 women, four men) undergoing bariatric surgery who had severe obesity but without comorbidities (hypertension, diabetes, and hyperlipidemia), and 28 control individuals who were matched for age and sex. CIMT and PWV of the left common carotid artery were measured. At 12-month follow-up after bariatric surgery, measurements were repeated in the 38 patients with obesity. Results: Mean baseline body mass index (BMI) in the MHO group was 40.55 ± 3.59 kg/m2, which decreased by 33.1% after bariatric surgery. Compared with controls, CIMT and PWV were increased in MHO (543.53 ± 55.29 vs. 407.82 ± 53.09 μm, 6.70 ± 1.22 vs. 5.45 ± 0.74 m/s, respectively; all P< 0.001). At 12 months post-bariatric surgery, CIMT in MHO was lower than baseline (466.79 ± 53.74 vs. 543.53 ± 55.29 μm, P= 0.009), but PWV was not significantly different from baseline (6.27 ± 0.86 vs. 6.70 ± 1.22 m/s, P= 0.132). Multivariate regression showed that BMI was an independent predictor of CIMT (β = 0.531, P< 0.001). Conclusion: Carotid artery structure and function were impaired in MHO, and improved carotid artery structure was associated with weight loss in MHO after bariatric surgery.

The grid-connected converter synchronizes with the power grid through the controller, so its out-of-step mechanism and out-of-step characteristics are different from synchronous generators. The out-of-step characteristics and out-of-step protection of grid-connected converter are urgent research topics at present. In this paper, the out-of-step mechanism of grid-connected converter under the low voltage ride through (LVRT) control strategy is analyzed by combining the phase plane method and the equal area criterion. The characteristics of current, voltage and measured impedance angle at the point of interconnection (PoI) are analyzed after the grid-connected converter is out-of-step, and compared with those of the traditional power system. On the basis of these, a novel out-of-step protection method for the grid-connected converter is proposed based on the measured impedance angle at the PoI. It judges the out-of-step by the characteristic that the measured impedance angle oscillates continuously and the difference of its extreme values increases gradually. The faster the out-of-step oscillation develops, the faster the protection acts, so it is adaptive. Finally, a MATLAB/Simulink simulation model is built to verify the effectiveness of the proposed protection method.

• An injectable decellularized extracellular matrix hydrogel is developed to deliver exosomes encapsulating curcumin locally to the infarcted area of the heart. • The solubility and bioavailability of curcumin are enhanced by exosomal encapsulation, and the hydrogel improves the retention of exosomes. • Intramyocardial injection of this hydrogel promotes angiogenesis, decreases collagen deposition, and prevents cardiac fibrosis to facilitate cardiac repair after myocardial infarction. Excessive cardiac fibrosis impairs cardiac repair after myocardial infarction (MI). In this work, an injectable composite hydrogel integrating natural biomaterials, exosomes, and bioactive molecules is developed to prevent or alleviate cardiac fibrosis. Curcumin, a natural molecule with antifibrotic activity, is encapsulated in the exosomes that are isolated from bone marrow-derived mesenchymal stem cells to enhance its water solubility and bioavailability. These composite exosomes are efficiently internalised by fibroblasts and effectively inhibit their transition to myofibroblasts in vitro. Decellularized porcine cardiac extracellular matrix (dECM) hydrogel is used as the carrier for delivering these composite exosomes to the infarcted myocardium, not only improving the retention of exosomes but also providing mechanical support and structural protection. Injection of this hydrogel into the infarcted heart of a mouse MI model leads to a decrease in collagen deposition, alleviation of fibrosis, a reduction in infarct size, and an improvement in cardiac function. The reported composite hydrogel comprising natural materials and biomolecules exhibits good biocompatibility and bioactivity. Altogether, this study demonstrates that the dECM hydrogel is a suitable platform for the local delivery of antifibrotic biomolecule-encapsulating exosomes to prevent myocardial fibrosis after MI and have great potential for the treatment of MI in clinical settings. [Display omitted] [ABSTRACT FROM AUTHOR]

Blue horizontal-branch stars (BHBs) are ideal tracers for studying the Milky Way (MW) due to their bright and nearly constant magnitude. However, an incomplete screen of BHBs from a survey would result in bias of estimation of the structure or mass of the MW. With surveys of large sky telescopes like the Sloan Digital Sky Survey (SDSS), it is possible to obtain a complete sample. Thus, detecting BHBs from massive photometric images quickly and effectually is necessary. The current acquisition methods of BHBs are mainly based on manual or semi-automatic modes. Therefore, novel approaches are required to replace manual or traditional machine-learning detection. The mainstream deep-learning-based object-detection methods are often vanilla convolutional neural networks whose ability to extract global features is limited by the receptive field of the convolution operator. Recently, a new Transformer-based method has benefited from the global receptive field advantage brought by the self-attention mechanism, exceeded the vanilla convolution model in many tasks, and achieved excellent results. Therefore, this paper proposes a hybrid convolution and Transformer model called AstroYOLO to take advantage of the convolution in local feature representation and Transformer’s easier discovery of long-distance feature dependences. We conduct a comparative experiment on the 4799 SDSS DR16 photometric image dataset. The experimental results show that our model achieves 99.25% AP@50, 93.79% AP@75, and 64.45% AP@95 on the test dataset, outperforming the YOLOv3 and YOLOv4 object-detection models. In addition, we test on larger cutout images based on the same resolution. Our model can reach 99.02% AP@50, 92.00% AP@75, and 61.96% AP@95 respectively, still better than YOLOv3 and YOLOv4. These results also suggest that an appropriate size for cutout images is necessary for the performance and computation of object detection. Compared with the previous models, our model has achieved satisfactory object-detection results and can effectively improve the accuracy of BHB detection.

• A multifunctional dressing based on bacterial cellulose deposited with a tannic acid/Cu2+ ion/Mg2+ ion complex film (BTCM) is developed. • The BTCM membrane can effectively eradicate bacteria in the wound area under a short-term near-infrared irradiation. • The BTCM membrane can promote proliferation, migration, and tube formation of endothelial cells in vitro and angiogenesis in vivo. • The BTCM membrane can accelerate the healing process of the bacteria-infected full-thickness skin wounds. For most traditional wound dressings, it is challenging to simultaneously eliminate bacteria and promote angiogenesis to accelerate the healing process of bacteria-infected wounds. In this work, we develop a multifunctional dressing based on bacterial cellulose (BC) deposited with a tannic acid/Cu2+ ion/Mg2+ ion (TCM) complex film. Overall, the TCM complex exhibits robust interfacial adhesion to modify BC and good photothermal properties to effectively eradicate bacteria in the wound area under near-infrared (NIR) irradiation. The individual components of the TCM complex have several advantageous features for wound healing, such as antibacterial ability and negligible cytotoxicity; in particular, the released Cu2+ and Mg2+ ions are favorable for the proliferation, migration, and tube formation of endothelial cells in vitro. The results of in vivo experiments demonstrated that with the assistance of NIR irradiation, this composite dressing is more effective than traditional gauze or pristine BC dressing in promotion of angiogenesis and collagen deposition without causing remarkable inflammation, thereby accelerating the healing process of bacteria-infected full-thickness skin wounds. This work thus provides a simple and facile way to fabricate multifunctional BC-based dressings that could be potentially used for treating infected wounds. [Display omitted] [ABSTRACT FROM AUTHOR]

Polarization (P), angular index (l), and radius index (p) are three independent degrees of freedom (DoFs) of vector vortex beams, which have found extensive applications in various domains. While efficient sorting of a single DoF has been achieved successfully, simultaneous sorting of all these DoFs in a compact and efficient manner remains a challenge. In this study, we propose a beam sorter that simultaneously handles all the three DoFs using a diffractive deep neural network (D2NN), and demonstrate the robust sorting of 120 Laguerre–Gaussian (LG) modes experimentally in the visible spectrum. Our proposed beam sorter underscores the considerable potential of D2NN in optical field manipulation and promises to enhance the diverse applications of vector vortex beams.

• A nanoplatform equipped with "disruption and killing" functions is designed to enhance the effectiveness of conventional antibiotics for biofilm eradication. • The nanoplatform can degrade the polysaccharides of extracellular polymeric substances to disrupt the structural integrity of biofilms. • Under near-infrared irradiation, the nanoplatform facilitates the release and the bacterial uptake of rifampicin to effectively eliminate the bacteria within biofilms. Due to the absence of timely and effective therapies, infections induced by bacterial biofilms have been widely acknowledged as a significant global public health concern. In modern times, aside from surgical intervention (when appropriate), antibiotics are the sole clinical option for treating biofilm-associated infections. However, the rise of drug resistance, as well as the poor therapeutic effects of current treatment regimens in eliminating biofilms highlight the requirement for novel strategies to enhance the accessibility of antibiotics in the "post-antibiotic era". The current study presents a multifunctional nanoplatform equipped with a "disruption and killing" function to enhance the effectiveness of conventional antibiotics for the eradication of biofilms. Herein, mesoporous silica nanoparticles were employed as carriers to encapsulate the model antibiotic rifampicin (Rif). Subsequently, the nanoparticles were coated with layers of the tannic acid/iron ion (TA/Fe) complex and immobilized with α-amylase. The α-amylase present in the outer layer can degrade the polysaccharides of extracellular polymeric substances (EPS), which in turn disrupts the structural integrity of the biofilms, thus facilitating the entry of the nanoplatform. When exposed to near-infrared (NIR) light, the TA/Fe complex layers can generate heat, which facilitates the release of Rif and increases the bacterial uptake of Rif by damaging the bacterial cell membrane, ultimately resulting in the elimination of bacteria within biofilms. The in vitro experiments demonstrated that this nanoplatform effectively eliminated over 99% of biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa when exposed to NIR radiation for 10 min. Additionally, in vivo experimental findings further validated the extensive therapeutic efficacy of this nanoplatform against biofilm-infected wounds, accelerating the rate of healing and reducing inflammatory reactions. To summarize, this nanoplatform provides a novel avenue to improve the effectiveness of conventional antibiotics in eradicating bacterial biofilms. [Display omitted] [ABSTRACT FROM AUTHOR]

• An injectable alginate/fibrin hydrogel is developed to deliver cardiomyocytes and VEGF locally to the infarcted area of the heart. • This hydrogel supports the retention and integration of the transplanted cardiomyocytes into the host myocardium. • The delivered VEGF is favorable for blood recovery to improve the survival of cardiomyocytes. • Intramyocardial injection of this hydrogel promotes angiogenesis, inhibits fibrosis, and improves cardiac function after myocardial infarction. Myocardial infarction (MI) is one of the typical cardiovascular diseases, which persist as the leading cause of death globally. Due to the poor regenerative capability of endogenous cardiomyocytes (CMs), the transplantation of exogenous CMs becomes a promising option for MI treatment. However, the low retention and survival of transplanted cells still limit the clinical translation of cell therapy. Herein, an alginate/fibrin-based injectable hydrogel was prepared for the delivery of neonatal CMs and an angiogenesis agent vascular endothelial growth factor (VEGF) locally to the infarcted area of the heart. This hydrogel combined the specific advantages of alginate and fibrin with proper mechanical properties and cell affinity, showing good biocompatibility to support the retention and integration of the transplanted CMs to the host myocardium. Moreover, the delivered VEGF was favorable for the blood recovery to mitigate the ischemic microenvironment of the infarcted area and thus improved the survival of the transplanted CMs. Intramyocardial injection of this hydrogel to the infarcted area of the heart promoted angiogenesis, inhibited fibrosis, and improved cardiac function, exhibiting great potential for MI treatment. [ABSTRACT FROM AUTHOR]

Transplantation of exogenous cardiomyocytes (CMs) is a hopeful method to treat myocardial infarction (MI). However, its clinical application still remains challenging due to low retention and survival rates of the transplanted cells. Herein, a stromal cell-derived factor 1 (SDF-1)-loaded injectable hydrogel based on a decellularized porcine extracellular matrix (dECM) is developed to encapsulate and deliver CMs locally to the infarct area of the heart. The soluble porcine cardiac dECM is composed of similar components such as the human cardiac ECM, which could be self-assembled into a nanofibrous hydrogel at physiological temperature to improve the retention of transplanted CMs. Furthermore, the chemokine SDF-1 could recruit endogenous cells to promote angiogenesis, mitigating the ischemic microenvironment and improving the survival of CMs. The results in vitroshow that this composite hydrogel exhibits good biocompatibility, anti-apoptosis property, and chemotactic effects for mesenchymal stromal cells and endothelial cells through SDF-1-CXCR4 axis. Moreover, intramyocardial injection of this composite hydrogel to the infarcted area leads to the promotion of angiogenesis and inhibition of fibrosis, reducing the infarction size and improving the cardiac function. The combination of natural biomaterials, exogenous cells, and bioactive factors shows potential for MI treatment in the clinical application.

The intermediacy of alkoxy radicals in cerium-catalyzed C–H functionalization via H-atom abstraction has been unambiguously confirmed. Catalytically relevant Ce(IV)–alkoxide complexes have been synthesized and characterized by X-ray diffraction. Operando electron paramagnetic resonance and transient absorption spectroscopy experiments on isolated pentachloro Ce(IV) alkoxides identified alkoxy radicals as the sole heteroatom-centered radical species generated via ligand-to-metal charge transfer (LMCT) excitation. Alkoxy-radical-mediated hydrogen atom transfer (HAT) has been verified via kinetic analysis, density functional theory (DFT) calculations, and reactions under strictly chloride-free conditions. These experimental findings unambiguously establish the critical role of alkoxy radicals in Ce-LMCT catalysis and definitively preclude the involvement of chlorine radical. This study has also reinforced the necessity of a high relative ratio of alcohol vs Ce for the selective alkoxy-radical-mediated HAT, as seemingly trivial changes in the relative ratio of alcohol vs Ce can lead to drastically different mechanistic pathways. Importantly, the previously proposed chlorine radical–alcohol complex, postulated to explain alkoxy-radical-enabled selectivities in this system, has been examined under scrutiny and ruled out by regioselectivity studies, transient absorption experiments, and high-level calculations. Moreover, the peculiar selectivity of alkoxy radical generation in the LMCT homolysis of Ce(IV) heteroleptic complexes has been analyzed and back-electron transfer (BET) may have regulated the efficiency and selectivity for the formation of ligand-centered radicals.

• A facile method is developed for fabrication of a superhydrophobic photothermal coating based on candle soot. • The coating can resist initial bacterial adhesion and kill the residual bacteria on the surface under NIR irradiation, preventing long-term biofilm formation. • The coating exhibits long-term storage stability and could be deposited on diverse practical substrates. Bacterial biofilms formed on the material surfaces have posed a series of serious problems for human health and industries. The treatment of mature biofilms is particularly difficult because they are inherently highly resistant against antibiotics and other adverse factors. The prevention is strategically advantageous over the treatment, and thus the development of innovative surfaces with capability to inhibit biofilm formation is highly demanded. In this work, we developed a superhydrophobic photothermal coating for prevention of biofilm formation, which was based on candle soot with hierarchical structure and excellent light-to-heat conversion ability. This coating was fabricated by deposition of a candle soot layer on the substrate, followed by sequential chemical vapor deposition of tetraethoxysilane and immobilization of fluorinated silane to make the coating robust and superhydrophobic. The resulted coating could repel a majority of bacteria from the surface at the early stage, and then eradicate a small number of bacteria remained on the surface under a short-term irradiation of near-infrared laser. The combination of anti-adhesive property and photothermal bactericidal property endowed the coating with good antibiofilm property to prevent biofilm formation for at least 2 weeks. This coating is facile for deposition on various substrates with good storage stability, showing great potential for diverse practical applications to solve the biofilm-associated problems of materials and devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Aiming at the present situation that the existing pole bus protection for the LCC~MMC hybrid HVDC system is simple in principle and cannot protect DC filter, this paper proposes a novel extended pole bus protection principle. Firstly, it constructed the equivalent circuits of LCC~MMC hybrid HVDC system in the normal operation state, fault on the elements within the protection zone, and DC transmission line fault, respectively, analyzed the direction of DC current on each measurement point in each case. On these bases, this paper proposed a DC current direction-based extended pole bus protection principle, and theoretically proved that the fault on DC transmission line and the AC system will not cause the maloperation. Compared with the existing pole bus protection, the proposed protection not only cover its protection zone, but also can reflect the fault on the DC filter branch. The simulation results verified that the proposed protection has clear selectivity for the internal fault and external fault.

• A facile method is developed for endowing bacterial cellulose (BC) with antifouling and photothermal antibacterial properties. • The modified BC is fabricated by physical incorporation of gold nanorods followed by deposition of a phase-transitioned protein film. • The modified BC can suppress bacterial adhesion and kill the bacteria that broke through the antifouling layer under NIR irradiation. • The modified BC exhibits negligible cytotoxicity in vitro and good histocompatibility in vivo. Bacterial cellulose (BC) is one of the most versatile natural biopolymers with unique physical, chemical, and biological features. However, the lack of intrinsic antibacterial property of native BC limits its broad biomedical applications where such property is highly required to prevent contamination or infection caused by attached bacteria. In this work, we developed a simple and facile method to fabricate a dual-functional BC membrane by physical incorporation of gold nanorods (GNRs) followed by deposition of a phase-transitioned bovine serum albumin (PTB) film. Due to the broad-spectrum antifouling property of the PTB film, the resulting membrane could prevent the adhesion and accumulation of bacteria. A few bacteria that broke through the protection of the PTB film could be eradicated under short-term irradiation of a near-infrared laser due to the excellent photothermal property of incorporated GNRs. The whole fabrication was conducted in a simple and environmentally friendly manner, avoiding complicated processes and toxic organic solvents. Moreover, because all the components were biocompatible, the resulting membrane showed negligible cytotoxicity in vitro and good histocompatibility in vivo. This work thus provided a reliable way to endow BC with antibacterial property, being beneficial for diverse biomedical applications. [ABSTRACT FROM AUTHOR]

Intracellular delivery of functional molecules is of great importance in various biomedical and biotechnology applications. Recently, nanoparticle-based photothermal poration has attracted increasing attention because it provided a facile and efficient method to permeabilize cells transiently, facilitating the entry of exogenous molecules into cells. However, this method still has some safety concerns associated with the nanoparticles that bind to the cell membranes or enter the cells. Herein, a nanoplatform with both photothermal property and sugar-triggered cleaning ability for intracellular delivery is developed based on phenylboronic acid (PBA) functionalized porous magnetic nanoparticles (named as M-PBA). The M-PBA particles could bind to the target cells effectively through the specific interactions between PBA groups and the cis-diol containing components on the cell membrane. During a short-term near-infrared irradiation, the bound particles convert absorbed light energy to heat, enabling high-efficiency delivery of various exogenous molecules into the target cells via a photothermal poration mechanism. After delivery, the bound particles could be easily “cleaned” from the cell surface via mild sugar-treatment and collected by a magnet, avoiding the possible side effects caused by the entrance of particles or their fragments. The delivery and cleaning process is short and effective without compromising the viability and proliferation ability of the cells with delivered molecules, suggesting that the M-PBA particles could be used as promising intracellular delivery agents with a unique combination of efficiency, safety, and flexibility.

Nasopharyngeal carcinoma (NPC) is an epithelia-derived malignancy with a distinctive geographic distribution. Cystathionine γ-lyase (CSE) is involved in cancer development and progression. Nevertheless, the role of CSE in the growth of NPC is unknown. In this study, we found that CSE levels in human NPC cells were higher than those in normal nasopharyngeal cells. CSE overexpression enhanced the proliferative, migrative, and invasive abilities of NPC cells and CSE downregulation exerted reverse effects. Overexpression of CSE decreased the expressions of cytochrome C, cleaved caspase (cas)-3, cleaved cas-9, and cleaved poly-ADP-ribose polymerase, whereas CSE knockdown exhibited reverse effects. CSE overexpression decreased reactive oxygen species (ROS) levels and the expressions of phospho (p)-extracellular signal-regulated protein kinase 1/2, p-c-Jun N-terminal kinase, and p-p38, but promoted the expressions of p-phosphatidylinositol 3-kinase (PI3K), p-AKT, and p-mammalian target of rapamycin (mTOR), whereas CSE knockdown showed oppose effects. In addition, CSE overexpression promoted NPC xenograft tumor growth and CSE knockdown decreased tumor growth by modulating proliferation, angiogenesis, cell cycle, and apoptosis. Furthermore, DL-propargylglycine (an inhibitor of CSE) dose-dependently inhibited NPC cell growth via ROS-mediated mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR pathways without significant toxicity. In conclusion, CSE could regulate the growth of NPC cells through ROS-mediated MAPK and PI3K/AKT/mTOR cascades. CSE might be a novel tumor marker for the diagnosis and prognosis of NPC. Novel donors/drugs that inhibit the expression/activity of CSE can be developed in the treatment of NPC.

• Biomaterials used for cardiac patches are classified according to their sources. • The required properties for the biomaterials to make cardiac patches are introduced. • The specific advantages and shortcomings of different types of cardiac patches are discussed. • The development tendency of biomaterials based cardiac patches is prospected. Myocardial infarction (MI) is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium, resulting in a life-threatening condition. To repair the damaged myocardium in MI, researchers are looking forwards to new ways to postpone the progression of myocardial injury. Cardiac patches, the scaffolds layered on the heart surface, can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells, showing considerable curative effect in the treatment of MI. Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches. In this review, we focus on the recent progress on these biomaterials-based cardiac patches, which could be categorized into two types according to the sources of materials including (ⅰ) natural materials and (ⅱ) synthetic materials. The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented. [Display omitted] [ABSTRACT FROM AUTHOR]

Biofilms formed from the pathogenic bacteria that attach to the surfaces of biomedical devices and implantable materials result in various persistent and chronic bacterial infections, posing serious threats to human health. Compared to the elimination of matured biofilms, prevention of the formation of biofilms is expected to be a more effective way for the treatment of biofilm-associated infections. Herein, we develop a facile method for endowing diverse substrates with long-term antibiofilm property by deposition of a hybrid film composed of tannic acid/Cu ion (TA/Cu) complex and poly(ethylene glycol) (PEG). In this system, the TA/Cu complex acts as a multifunctional building block with three different roles: (i) as a versatile “glue” with universal adherent property for substrate modification, (ii) as a photothermal biocidal agent for bacterial elimination under irradiation of near-infrared (NIR) laser, and (iii) as a potent linker for immobilization of PEG with inherent antifouling property to inhibit adhesion and accumulation of bacteria. The resulted hybrid film shows negligible cytotoxicity and good histocompatibility and could prevent biofilm formation for at least 15 days in vitroand suppress bacterial infection in vivo, showing great potential for practical applications to solve the biofilm-associated problems of biomedical materials and devices.

Selective functionalization of inactive C(sp3)–F bonds to prepare medicinally interesting aryldifluoromethylated compounds remains challenging. One promising route is the transition-metal-catalyzed cross-coupling through oxidative addition of the C(sp3)–F bond in trifluoromethylarenes (ArCF3), which are ideal precursors for this process due to their ready availability and low cost. Here, we report an unprecedented excited-state palladium catalysis strategy for selective defluoroarylation of trifluoromethylarenes with arylboronic acids. This visible-light-induced palladium-catalyzed cross-coupling proceeds under mild reaction conditions and allows transformation of a variety of arylboronic acids and ArCF3. Preliminary mechanistic studies reveal that the oxidative addition of the C(sp3)–F bond in ArCF3to excited-state palladium(0) via a single electron transfer pathway is responsible for the C(sp3)–F bond activation.

Attachment of bacteria and subsequent formation of biofilms on material surfaces lead to serious consequences including infection, contamination and biofouling, posing a prominent threat to human health and causing problems in many industries. Therefore, it is highly desirable to endow the surfaces with antibacterial properties. Traditional antibacterial surfaces are designed via either bacteria-resisting strategy to prevent the initial adhesion of bacteria or bacteria-killing strategy to eradicate any bacteria that attach to the surface. However, these single-function surfaces have their inherent shortcomings and cannot realize long-term efficacy against bacteria. In recent years, various dual-function antibacterial surfaces with both bacteria-resisting and bacteria-killing properties together have been developed, showing better performance for combating surface-attached bacteria and preventing formation of biofilms. In this review, we summarize the recent development of these dual-function antibacterial surfaces. We focus on the design principles and fabrication strategies of such surfaces and highlight the representative examples, which are categorized specifically into two types according to the anti-adhesive and bactericidal properties are simultaneous or switchable. A brief perspective is finally presented on current challenges and future research directions. [ABSTRACT FROM AUTHOR]

The development of economical multiphase photocatalysts is a significant challenge in achieving large-scale industrialization. Rational catalyst design can help in achieving efficient, energy-saving, and green catalytic reactions, making it more feasible to screen potential catalyst candidates. In this paper, we have successfully developed a high-efficiency photocatalyst Cu-doped Cu2WO4(OH)2(CWOH-y, where y represents the molar ratio of copper tungsten source), which can catalyze the aerobic coupling reaction of amines to produce corresponding imines under visible light irradiation. N-benzylidenebenzylamine is synthesized under visible light at 25 °C with an 89 % yield. Under natural light at around 35 °C (mean light intensity of 50 mW/cm2), 94 % of the benzylamine is converted, and 97 % of the product is N-benzylidenebenzylamine. The catalyst exhibits high efficiency due to the synergistic effect of doped Cu, Cu2WO4(OH)2, and visible light. This combination generates a significant amount of superoxide free radicals and singlet oxygen when exposed to visible light. Furthermore, the catalyst demonstrates universality and stability with a wide range of amine derivatives. This study introduces a new environmentally friendly photocatalytic pathway for the synthesis of imines and emphasizes the potential applications of Cu2WO4(OH)2.

Myocardial infarction (MI) is associated with inflammatory reaction, which is a pivotal component in MI pathogenesis. Moreover, excessive inflammation post-MI can lead to cardiac dysfunction and adverse remodeling, emphasizing the critical need for an effective inflammation-regulating treatment for cardiac repair. Macrophage polarization is crucial in the inflammation process, indicating its potential as an adjunct therapy for MI. In this study, we developed an injectable alginate hydrogel loaded with annexin A1 (AnxA1, an endogenous anti-inflammatory and pro-resolving mediator) for MI treatment. In vitro results showed that the composite hydrogel had good biocompatibility and consistently released AnxA1 for several days. Additionally, this hydrogel led to a reduced number of pro-inflammatory macrophages and an increased proportion of pro-healing macrophages via the adenosine monophosphate (AMP)-activated protein kinase (AMPK)-mammalian target of the rapamycin (mTOR) axis. Furthermore, the intramyocardial injection of this composite hydrogel into a mouse MI model effectively modulated macrophage transition to pro-healing phenotypes. This transition mitigated early inflammatory responses and cardiac fibrosis, promoted angiogenesis, and improved cardiac function. Therefore, our study findings suggest that combining biomaterials and endogenous proteins for MI treatment is a promising approach for limiting adverse cardiac remodeling, preventing cardiac damage, and preserving the function of infarcted hearts.

Microplastic records from lake cores can reconstruct the plastic pollution history. However, the associations between anthropogenic activities and microplastic accumulation are not well understood. Huguangyan Maar Lake (HML) is a deep-enclosed lake without inlets and outlets, where the sedimentary environment is ideal for preserving a stable and historical microplastic record. Microplastic (size: 10–500 μm) characteristics in the HML core were identified using the Laser Direct Infrared Imaging system. The earliest detectable microplastics appeared unit in 1955 (1.1 items g–1). The microplastic abundance ranged from n.d. to 615.2 items g–1in 1955–2019 with an average of 134.9 items g–1. The abundance declined slightly during the 1970s and then increased rapidly after China’s Reform and Opening Up in 1978. Sixteen polymer types were detectable, with polyethylene and polypropylene dominating, accounting for 23.5 and 23.3% of the total abundance, and the size at 10–100 μm accounted for 80%. Socioeconomic factors dominated the microplastic accumulation based on the random forest modeling, and the contributions of GDP per capita, plastic-related industry yield, and total crop yield were, respectively, 13.9, 35.1, and 9.3% between 1955–2019. The total crop yield contribution further increased by 1.7% after 1978. Coarse sediment particles increased with soil erosion exacerbated microplastics discharging into the sediment.

Biofilm contamination presents a significant threat to public health, the food industry, and aquatic/marine-related applications. In recent decades, although various methods have emerged to combat biofilm contamination, the intricate and persistent nature of biofilms makes complete eradication challenging. Therefore, innovative alternative solutions are imperative for addressing biofilm formation. Instead of solely focusing on the eradication of mature biofilms, strategically advantageous measures involve the delay or prevention of biofilm formation on surfaces. Quorum sensing, a communication system enabling bacteria to coordinate their behavior based on population density, plays a pivotal role in biofilm formation for numerous microbial species. Materials possessing antibiofilm properties that target quorum sensing have gained considerable attention for their potential to prevent biofilm formation. This Review consolidates recent research progress on the utilization of materials with antiquorum sensing properties for combating biofilm formation. These materials can be categorized into three distinct types: (i) antibiofilm nanomaterials, (ii) antibiofilm surfaces, and (iii) antibiofilm hydrogels with antiquorum sensing capabilities. Finally, the Review concludes with a brief discussion of current challenges and outlines potential avenues for future research.

Gene transfection, defined by the delivery of nucleic acids into cellular compartments, stands as a crucial procedure in gene therapy. While branched polyethylenimine (PEI) is widely regarded as the “gold standard” for nonviral vectors, its cationic nature presents several issues, including nonspecific protein adsorption and notable cytotoxicity. Additionally, it often fails to achieve high transfection efficiency, particularly with hard-to-transfect cell types. To overcome these challenges associated with PEI as a vector for plasmid DNA (pDNA), the photothermal agent indocyanine green (ICG) is integrated with PEI and pDNA to form the PEI/ICG/pDNA (PI/pDNA) complex for more efficient and safer gene transfection. The negatively charged ICG serves a dual purpose: neutralizing PEI’s excessive positive charges to reduce cytotoxicity and, under near-infrared irradiation, inducing local heating that enhances cell membrane permeability, thus facilitating the uptake of PI/pDNA complexes to boost transfection efficiency. Using pDNA encoding vascular endothelial growth factor as a model, our system shows enhanced transfection efficiency in vitro for hard-to-transfect endothelial cells, leading to improved cell proliferation and migration. Furthermore, in vivo studies reveal the therapeutic potential of this system in accelerating the healing of infected wounds by promoting angiogenesis and reducing inflammation. This approach offers a straightforward and effective method for gene transfection, showing potentials for tissue engineering and cell-based therapies.