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Abundant proxy records suggest a profound reorganization of the Atlantic Meridional Overturning Circulation (AMOC) during the Last Glacial Maximum (LGM, ~21,000 y ago), with the North Atlantic Deep Water (NADW) shoaling significantly relative to the present-day (PD) and forming Glacial North Atlantic Intermediate Water (GNAIW). However, almost all previous observational and modeling studies have focused on the zonal mean two-dimensional AMOC feature, while recent progress in the understanding of modern AMOC reveals a more complicated three-dimensional structure, with NADW penetrating from the subpolar North Atlantic to lower latitude through different pathways. Here, combining 231Pa/230Th reconstructions and model simulations, we uncover a significant change in the three-dimensional structure of the glacial AMOC. Specifically, the mid-latitude eastern pathway (EP), located east of the Mid-Atlantic Ridge and transporting about half of the PD NADW from the subpolar gyre to the subtropical gyre, experienced substantial intensification during the LGM. A greater portion of the GNAIW was transported in the eastern basin during the LGM compared to NADW at the PD, resulting in opposite 231Pa/230Th changes between eastern and western basins during the LGM. Furthermore, in contrast to the wind-steering mechanism of EP at PD, the intensified LGM EP was caused primarily by the rim current forced by the basin-scale open-ocean convection over the subpolar North Atlantic. Our results underscore the importance of accounting for three-dimensional oceanographic changes to achieve more accurate reconstructions of past AMOC. [ABSTRACT FROM AUTHOR]

The application of photo responsive crystals to useful actuation demands a rational design to elicit controllable movement. The [2+2] photocycloaddition reaction triggers mechanical motion using associated photosalient (PS) effects. We herein report a coordination site selective occupation strategy to modulate the arrangement of C=C bonds and thereby tune the PS effect. Replacing or repositioning the donor atom at one end of the linear ligand allowed for a greater level of molecular structural flexibility, facilitating [2+2] photocycloaddition. The distance between photoreactive centres and coordination sites was adjusted by ligand design to regulate PS behaviour. This work suggests new avenues for modulating PS movement to achieve useful motion. [ABSTRACT FROM AUTHOR]

Three photoactive Cd(II) coordination polymers (CPs), [Cd (Fsbpe)(DBBA)2]·2DMF (CP1), [Cd(Fepbpe)(DBBA)2]·2DMF (CP2) and [Cd(Fsbpeb)(DBBA)2] (CP3) (DBBA = 3,5-dibromobenzoic acid, DMF = dimethyl formamide) with similar 1D chain motifs exhibited completely different photosalient behaviors (PS) in response to UV light. Mechanical motion was triggered by [2+2] photocycloaddition and regulated by positioning of the photoactive alkene centers relative to the crystal axis. This solid-state reaction was reversed by heating and photomechanical behaviour was repeated over several cycles. A simple photoactuating device was prepared using a CP3–PVA composite. [ABSTRACT FROM AUTHOR]

Partial discharge (PD) is one of the key factors leading to premature insulation failure of film capacitors used in pulse power devices. To study the effect of frequency on the PD characteristics of biaxially oriented polypropylene (BOPP) film, a sphere-plate electrode was used to simulate defects of the air gap between the film layers. PD experiments of the BOPP film were carried out under 1, 10, 100, 500 Hz, and 1 kHz with a rising edge of 65 ns and a pulse width of 300 ns. The results show that the repetitive partial discharge inception voltage (RPDIV), the number of discharges, the rising stage discharge (RSD) amplitude, and the falling stage discharge (FSD) time-lag, all show an increase and then decrease with increasing pulse frequencies and reach a maximum value at a pulse frequency of 100 Hz. Moreover, the FSD discharge amplitude and the RSD discharge time-lag increase with an increasing pulse frequency. From the perspective of initial electron generation, the quantitative mathematical relationship between PD characteristics (RPDIV, PD amplitude, PD number, and PD time-lag) and frequency was established based on the Fowler–Nordheim field emission effect for the first time, which can reflect the influence of frequency on the memory effect and the development process of PD. The results can provide an experimental basis and a mechanistic explanation for the evaluation of PD characteristics for film capacitors under nanosecond pulse voltage. [ABSTRACT FROM AUTHOR]

Pulsed electric field-induced electroporation has been widely used, but its specific perforation theory has not been fully elucidated. Therefore, this Perspective paper takes as a clue the dynamic development relationship between the pore energy and the pore state in cell membranes. First, based on the contribution of line tension, surface tension, steric repulsion, and applied electric field to pore energy, the theoretical models of reversible electroporation of a microsecond pulsed electric field and irreversible electroporation of a high-frequency nanosecond pulsed electric field are reviewed. Then, the contribution of elastic strain energy to pore energy is increased, and the theoretical model of pulsed electric field electroporation considering the mechanical properties of cell membranes is further reviewed. Based on the contribution of magnetic stress generated by the magnetic field and the gradient magnetic field to pore energy, a theoretical model of cell membrane magnetoporation under the action of a pulsed magnetic field is proposed, which lays a theoretical foundation for the popularization and application of non-contact cell membrane perforation technology. [ABSTRACT FROM AUTHOR]

Conductive polymer composites require high conductive filler loadings to achieve relatively ideal electromagnetic interference (EMI) shielding performance, which brings problems such as heavy weight and poor processability and ultimately limits their application in the aerospace field. To solve the above problems and realize the preparation of excellent EMI shielding composites with low filler loadings, a bipolar pulsed electric field-induced graphene nanoplatelets (GNPs) alignment method is proposed in this paper to improve the electrical conductivity and EMI shielding performance. The orientation and alignment of GNPs in the matrix were characterized by x-ray diffraction and scanning electron microscopy, and the results showed that GNPs formed a conductive network. The electrical conductivity of the composite material in the X-band was measured, and the results showed that the bipolar pulsed electric field could significantly improve the electrical conductivity of the composite material; the improvement percentage reached 100%–300% under the five filler loadings. In addition, the EMI shielding effectiveness of the composite material in the X-band was tested. The results showed that the EMI shielding effectiveness of the composite material with a mass fraction of 14% increased from 16.48–15.86 dB to 21.37–20.99 dB with the action of the bipolar pulsed electric field, and the improvement percentage was 32%. This is the first study on improving the EMI shielding performance of composite materials by applying a bipolar pulsed electric field, and it provides an effective method to prepare EMI shielding composites with low filler loadings. [ABSTRACT FROM AUTHOR]

The combination of magnetic fields and magnetic nanoparticles (MNPs) to kill cancer cells by magneto-mechanical force represents a novel therapy, offering advantages such as non-invasiveness, among others. Pulsed magnetic fields (PMFs) hold promise for application in this therapy due to advantages such as easily adjustable parameters; however, they suffer from the drawback of narrow pulse width. In order to fully exploit the potential of PMFs and MNPs in this therapy, while maximizing therapeutic efficacy within the constraints of the narrow pulse width, a feature-matching theory is proposed, encompassing the matching of three aspects: (1) MNP volume and critical volume of Brownian relaxation, (2) relaxation time and pulse width, and (3) MNP shape and the intermittence of PMF. In the theory, a microsecond-PMF generator was developed, and four kinds of MNPs were selected for in vitro cell experiments. The results demonstrate that the killing rate of the experimental group meeting the requirements of the theory is at least 18% higher than the control group. This validates the accuracy of our theory and provides valuable guidance for the further application of PMFs in this therapy. [ABSTRACT FROM AUTHOR]

INTRODUCTION Non-combustible nicotine products (NCNPs), such as heated tobacco products (HTPs) and nicotine vaping products (NVPs) have gained a significant nicotine market share in South Korea. This descriptive study examined patterns of regular cigarette and NCNP use among South Korean adults. METHODS Data were from the 2020 International Tobacco Control Korea Survey and included 4016 adults (aged ≥19 years) in the Republic of Korea who were regularly (at least weekly) using at least one NCNP (NVP/HTP, n=2117) and/or smoked cigarettes (n=3763) at the time of the survey. Weighted descriptive estimates were computed to assess respondents' nicotine product use among all respondents (exclusive, dual, or triple use). Thereafter, we identified sociodemographic characteristics associated with NCNP use (n=2117). RESULTS Among Korean adults who were smoking cigarettes, 83.1% (95% CI: 81.6- 84.6) did so exclusively, and 16.9% (95% CI: 15.4-18.4) smoked cigarettes and used NCNPs. Among those who used HTPs (n=1877), 14.9% (95% CI: 11.5-18.4) did so exclusively, 59.6% used HTPs and smoked cigarettes (95% CI: 55.4-63.1), 4.2% used HTPs and vaped (95% CI: 11.5-18.4), and 21.6 % (95% CI: 18.9-24.2) used all three products. Of adults who used HTPs and smoked cigarettes, 86.6% smoked daily. Among those who vaped (n=865), 13.3% did so exclusively (95% CI: 9.4-17.1), 55.6% (95% CI: 49.6-61.5) vaped and smoked cigarettes, 5.1% (95% CI: 1.7-8.6) used HTPs and vaped, and 26.1% (95% CI: 22.1-30.1) used all three products. Of adults who vaped and smoked cigarettes, 82.4% (95% CI: 77.1-87.7) smoked daily. CONCLUSIONS Cigarettes remain the most commonly used nicotine product in South Korea, and among adults using heated tobacco and/or vaping products, the majority were also smoking. Research is urgently needed to assess whether adults who are using an NCNP are doing so to quit, or rather to complement their cigarette smoking. [ABSTRACT FROM AUTHOR]

One of the main challenges in small molecule drug discovery is finding novel chemical compounds with desirable activity. Traditional drug development typically begins with target selection, but the correlation between targets and disease remains to be further investigated, and drugs designed based on targets may not always have the desired drug efficacy. The emergence of machine learning provides a powerful tool to overcome the challenge. Herein, a machine learning‐based strategy is developed for de novo generation of novel compounds with drug efficacy termed DTLS (Deep Transfer Learning‐based Strategy) by using dataset of disease‐direct‐related activity as input. DTLS is applied in two kinds of disease: colorectal cancer (CRC) and Alzheimer's disease (AD). In each case, novel compound is discovered and identified in in vitro and in vivo disease models. Their mechanism of actionis further explored. The experimental results reveal that DTLS can not only realize the generation and identification of novel compounds with drug efficacy but also has the advantage of identifying compounds by focusing on protein targets to facilitate the mechanism study. This work highlights the significant impact of machine learning on the design of novel compounds with drug efficacy, which provides a powerful new approach to drug discovery. [ABSTRACT FROM AUTHOR]

With the change of people's dietary structures, obesity, diabetes, and other related chronic metabolic diseases characterized by energy metabolism disorders have become a public health problem worldwide. Stable isotope-resolved metabolomics (SIRM) as a novel technology to explore energy metabolism will certainly contribute to the development of functional foods to improve energy metabolism disorders. The purpose of this review is to elaborate on the technology processes of SIRM in the research of functional foods with improved energy metabolism disorders, and to promote the applications of this technology in functional food. The research strategies for functional foods for improving energy metabolism disorders were summarized. The progress of the application of SIRM on functional foods was elaborated and policy recommendations were also provided. In conclusion, the precise property of SIRM in revealing metabolic pathways will inevitably facilitate the development of functional foods in improving energy metabolism disorders. [ABSTRACT FROM AUTHOR]

The mechanical properties of the cell membrane play an important role in electroporation. This paper studied the influence of the mechanical properties of the cell membrane on the transition energy of electroporation through both modeling and experiments. An electromechanical coupling model of a single pore on the cell membrane was established in COMSOL, and the effect of elastic strain energy on the formation of pores was analyzed. Additionally, to compare the transition energy barrier of pores for different elastic properties of the cell membrane, electroporation experiments were carried out at different temperatures. The simulation showed that the elastic strain energy of the cell membrane increased the transition energy barrier of the pores. The experiments also showed that the transition energy barrier was larger when the elasticity of the cell membrane is intact, which was in good agreement quantitatively with the simulation results. We demonstrated that the mechanical properties of the cell membrane hinder the pore formation, which may be due to the increase of the transition energy barrier. We analyzed the possible mechanism of the effect of cell membrane mechanical properties on electroporation and found the contribution of cell membrane mechanical properties to electroporation during the delivery of exogenous substances, which can provide guidance for improving therapies in electrochemotherapy. [ABSTRACT FROM AUTHOR]

As an increasingly urbanized country, China faces significant disaster risks. Social vulnerability influences the ability to prepare for, respond to, and recover from disasters. Quantifying social vulnerability is a worthwhile study because it can provide information vital to understanding the interactions among individuals, communities, and society and can further help us improve disaster risk mitigation. Therefore, this paper presents a case study on the social vulnerability assessment of the inner area of Jiaxing, China. With household questionnaire data, we calculated the social vulnerability index (SoVI) through categorical principal component analysis (CATPCA). We also presented a holistic and detailed profile of social vulnerability that links three different levels (e.g., households, apartment blocks, and communities) and contains four aspects of SoVI, such as statistical information, spatial pattern, dimension attributes, and risk state combinations of variables. This profile also responded to criticisms about the index method's reductionist nature. Our results retained as much valuable information as we could, enabling a more holistic understanding of demographic, environmental, and social conditions that influence social vulnerability to disasters in the inner city of Jiaxing. [ABSTRACT FROM AUTHOR]

Objective: To explore role of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in idiopathic membranous nephropathy (IMN) and its possible mechanism of activation. Methods: A total of 135 patients with no adrenal corticosteroid and immunosuppressive therapy who were diagnosed with IMN by renal biopsy were collected, and 10 patients with renal tuberculosis and renal tumors who underwent nephrectomy were selected as control group. Immunohistochemical was used to detect NLRP3, tumor necrosis factor receptor-related factor 6 (TRAF6), Caspase-1, NF-κB p65, MAPK signaling pathway-related proteins, including phosphorylated ERK1/2 (p-ERK1/2), phosphorylated p38 (p-p38), phosphorylated JNK (p-JNK) expressions. Blood and 24-hour urine of IMN patients were collected, and 24-hour urine protein quantification, serum creatinine, creatinine clearance rate, blood urea nitrogen and other general clinical data were were analyzed, correlation between urine protein and NLRP3, Caspase-1, IL-1β, TNF- α, NLRP3 and TRAF6 were analyzed, respectively. Results: Compared with control group, 24-hour urine protein and serum creatinine of IMN patients were significantly increased (both P<0.05), and protein expressions of NLRP3 and Caspase-1 in kidney tissues of IMN patients were significantly increased (both P<0.05), among which renal tissue of stage II IMN patients had the highest protein expressions of NLRP3 and Caspase-1, IL-1β and TNF- α expressions were enhanced (both P<0.05), and IL-1β and TNF-α protein expressions in renal tissue of stage II IMN patients were the strongest, protein expressions of NF-κB p65, p-ERK1/2, p-p38 and p-JNK were significantly increased (all P<0.05) . 24-hour urinary protein of IMN patients was positively correlated with expression of NLRP3 protein in kidney tissues (r=0.689, P<0.01), positively correlated with Caspase-1 protein (r=0.614, P<0.000 1), positively correlated with IL-1β (r=0.708, P<0.000 1), positively correlated with TNF-α (r=0.594, P<0.01) . Conclusion: TRAF6 induces ERK1/2, p38 and JNK signaling pathways to stimulate activation of NLRP3 inflammasome through activation of NF-κB, which promotes occurrence of IMN and production of large amounts of urine protein. [ABSTRACT FROM AUTHOR]

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Purpose: Total hip arthroplasty (THA) is often associated with moderate to severe pain. The present study compared the efficacy of circum-psoas block (CPB) with supra-inguinal fascia iliaca block (SIFIB) for postoperative analgesia in patients undergoing THA.Patients and Methods: In this randomized trial, sixty-four patients undergoing THA were allocated randomly to the CPB group or SIFIB group with 40 mL of 0.3% ropivacaine. The primary outcome was dynamic pain score at 6 h postoperatively. Secondary outcomes included dynamic pain scores at 12, 24 and 48 h; static pain scores; sensory and motor block; opioid consumption; time to first opioid request; length of hospital stay; patient satisfaction; and adverse events.Results: CPB patients showed significantly lower dynamic pain scores at 6 (3.11 ± 0.66 vs 4.47 ± 0.74, respectively; P = 0.000), 12 (2.52 ± 0.73 vs 3.53 ± 0.85, respectively; P = 0.000) and 24 h (2.30 ± 0.57 vs 2.87 ± 0.71, respectively; P = 0.001) after surgery, as well as lower static pain scores at 6 and 12h (P = 0.001 and P = 0.033 respectively) than SIFIB patients. Lower opioid consumption was observed in the CPB group at 24 and 48 h (P = 0.000, both) than in the SIFIB group. Patients in the CPB group reported improved quadriceps strength at 6 and 12 h (P = 0.000, both), as well as better muscle strength of hip flexion at 6, 12 and 24 h (P = 0.000, P = 0.000 and P = 0.025 respectively). Compared with SIFIB, CPB was associated with increased sensory block coverage at 6, 12 and 24 h (P = 0.000, P = 0.000, and P =0.022, respectively).Conclusion: CPB has a greater potential to alleviate postoperative pain and improve recovery in THA patients than SIFIB. [ABSTRACT FROM AUTHOR]

Backgrounds: Gait disorder is associated with cognitive functional impairment, and this disturbance is more pronouncedly when performing additional cognitive tasks. Our study aimed to characterize gait disorders in mild cognitive impairment (MCI) under three dual tasks and determine the association between gait performance and cognitive function. Methods: A total of 260 participants were enrolled in this cross-sectional study and divided into MCI and cognitively normal control. Spatiotemporal and kinematic gait parameters (31 items) in single task and three dual tasks (serial 100-7, naming animals and words recall) were measured using a wearable sensor. Baseline characteristics of the two groups were balanced using propensity score matching. Important gait features were filtered using random forest method and LASSO regression and further described using logistic analysis. Results: After matching, 106 participants with MCI and 106 normal controls were recruited. Top 5 gait features in random forest and 4 ~ 6 important features in LASSO regression were selected. Robust variables associating with cognitive function were temporal gait parameters. Participants with MCI exhibited decreased swing time and terminal swing, increased mid stance and variability of stride length compared with normal control. Subjects walked slower when performing an extra dual cognitive task. In the three dual tasks, words recall test exhibited more pronounced impact on gait regularity, velocity, and dual task cost than the other two cognitive tests. Conclusion: Gait assessment under dual task conditions, particularly in words recall test, using portable sensors could be useful as a complementary strategy for early detection of MCI. [ABSTRACT FROM AUTHOR]

Single-domain magnetic particles have unique and excellent magnetic properties and are widely used in biomedical applications, but there are many mechanisms for their response to external magnetic fields. Different models apply under various conditions, which challenges researchers who want to choose a suitable model for their studies. Based on this situation, this paper comprehensively summarizes the mechanisms and models of magnetic loss of single-domain magnetic particles in an external magnetic field. Notably, this paper comprehensively summarizes the non-equilibrium kinetic model of the response of single-domain superparamagnetic particles to external magnetic fields. In this paper, the mechanism for hysteresis loss of single-domain ferromagnetic particles and a model for its calculation are presented, the Stoner–Wohlfarth (SW) model based on equilibrium state and the statistical mechanics model based on non-equilibrium state are introduced; then, the mechanism for the relaxation loss of single-domain superparamagnetic particles and a model for its calculation are introduced, and the linear response model based on equilibrium state and the statistical mechanics model based on non-equilibrium state are introduced in a general way. Lastly, the development of single-domain superparamagnetic particles is briefly prospected. This review provides a convenient reference for researchers to explore the magnetic properties of single-domain magnetic particles and promotes their application and development in the field of biomedicine. [ABSTRACT FROM AUTHOR]

Ammonia decomposition has attracted significant attention in recent years due to its ability to produce hydrogen without emitting carbon dioxide and the ease of ammonia storage. This paper reviews the recent developments in ammonia decomposition technologies for hydrogen production, focusing on the latest advances in catalytic materials and catalyst design, as well as the research progress in the catalytic reaction mechanism. Additionally, the paper discusses the advantages and disadvantages of each method and the importance of finding non-precious metals to reduce costs and improve efficiency. Overall, this paper provides a valuable reference for further research on ammonia decomposition for hydrogen production. [ABSTRACT FROM AUTHOR]

For decades, global warming and energy shortages have been two urgent problems in human society. The solar-driven photocatalytic conversion of carbon dioxide (CO2) into hydrocarbon fuels is expected to become a technology to solve these problems. Two-dimensional (2D) materials shine in the field of photocatalytic CO2 due to their layered structure, larger specific surface area, more active sites, and larger charge transfer efficiency. This article reviews the progress of CO2 reduction by several types of 2D materials in recent years. Generally, the reduction of CO2 is difficult in terms of kinetics and thermodynamics, but it is found through theoretical calculations and experiments that 2D materials have certain advantages in the reduction of CO2. Then the preparation methods of 2D materials are summarized and a variety of 2D materials are discussed and classified. Finally, an outlook on the development trend of 2D materials is made. This review aims to provide systematic and concise guidance for the design of 2D nanomaterials for photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built‐in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide‐cobalt nanowire arrays grown on carbon fiber paper (Ni2P‐CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni2P‐CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm−2, respectively. Moreover, the assembled lab‐scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface‐induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high‐performance heterogeneous electrocatalysts. [ABSTRACT FROM AUTHOR]

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built‐in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide‐cobalt nanowire arrays grown on carbon fiber paper (Ni2P‐CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni2P‐CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm−2, respectively. Moreover, the assembled lab‐scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface‐induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high‐performance heterogeneous electrocatalysts. [ABSTRACT FROM AUTHOR]

Nanosecond pulsed electric fields over 200 kV/mm have been used for filler alignment in polymer-based thin film (120–250 μm) composites to improve their thermal conductivity, but little research has been performed on bulk composites because of the requirement of an extremely high nanosecond pulsed voltage. In this paper, a microsecond pulsed voltage with a pulse width of 1 μs and an electric field of only 11.76 kV/mm was adopted for the first time to prepare bulk composites of 1.7 mm. The effects of frequency on nanosheets' orientation and the thermal conductivity of epoxy composites were studied. The orientation degree of BN nanosheets was determined based on cross-sectional scanning electron microscopy images and X-ray diffraction peaks. The orientation degree and thermal conductivity of epoxy composites increased with the increase of the frequency, but the increase rate was lower under higher frequencies. The thermal conductivity of composites containing 10 wt. % BN nanosheets prepared under 100 Hz was 0.588 W/mK, which was more than twice that of composites without an applied electric field. Additionally, an effective medium theory model was adopted for thermal conductivity modeling. In addition, thermogravimetric and differential scanning calorimetry analyses were performed to evaluate the thermal properties of the composites. The results showed that after BN orientation in epoxy resin, the composites had higher glass transition temperature and better thermal stability. Microsecond pulsed electric fields are promising for preparing bulk insulation composites with higher thermal conductivity. [ABSTRACT FROM AUTHOR]

The effective separation and migration of photogenerated charge carriers in bulk and on the surface of photocatalysts will significantly promote photocatalytic efficiency. However, the synchronous regulation of photocharges on both counts is challenging. Herein, the simultaneous separation of bulk and surface photocharges is conducted to enhance photocatalytic activity by coupling the surface defects and lattice engineering of bismuth oxybromide. The depth-modulated Bi5O7Br ultrathin nanosheets with an abundance of bismuth in the crystal structure increased the internal electric field, which propelled the separation and migration of photocharges from bulk to the surface. Creation of oxygen vacancies (OVs) on the nanosheet surface forms local electric fields, which can stimulate the migration of charges to active sites on the catalyst surface. Therefore, the OV-assembled Bi5O7Br nanosheets demonstrated enhanced photocatalytic degradation efficiency under simulated solar-light illumination. This study proved the possibility of charge governing via electric field modulation based on an integrated strategy. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs), which play a pivotal role in inducing either inflammatory or tolerogenic response based on their subtypes and environmental signals. Emerging evidence indicates that DCs are critical for initiation and progression of autoimmune diseases, including multiple sclerosis (MS). Current disease-modifying therapies (DMT) for MS can significantly affect DCs’ functions. However, the study on the impact of DMT on DCs is rare, unlike T and B lymphocytes that are the most commonly discussed targets of these therapies. Induction of tolerogenic DCs (tolDCs) with powerful therapeutic potential has been well-established to combat autoimmune responses in laboratory models and early clinical trials. In contrast to in vitro tolDC induction, in vivo elicitation by specifically targeting multiple cell-surface receptors has shown greater promise with more advantages. Here, we summarize the role of DCs in governing immune tolerance and in the process of initiating and perpetuating MS as well as the effects of current DMT drugs on DCs. We then highlight the most promising cell-surface receptors expressed on DCs currently being explored as the viable pharmacological targets through antigen delivery to generate tolDCs in vivo. [ABSTRACT FROM AUTHOR]

The development of soy protein‐based adhesives is an environment‐friendly strategy to fabricate formaldehyde‐free wood composite with desired properties. However, it remains challenge to effectively control crosslinking process and therefore tailor the property of soy protein‐based adhesives. Herein, inspired by the components of defatted soy flour, a controllable crosslinking system of soy protein and epichlorohydrin‐modified polyamidoamine was developed by adjusting the soybean polysaccharide contents. The results confirmed that soluble polysaccharide involved into the crosslinking system via Maillard reaction. Even though the weight ratios of polysaccharide in the adhesives increased from 0% to 60%, the water‐insoluble contents of the cured adhesives were slightly driven down from 89.15% to 84.98%, meanwhile thermal stability of the cured adhesives can be improved 1.4 times. Moreover, polysaccharide can be used as a small molecular additive to reduce initial viscosity of the adhesive and achieve improved spread property and mechanical interlock with plywood. Notably, the soaked wet bond strength of the resultant plywood reached 1.58 MPa and the cycled wet bond strength reached 1.17 MPa, which meet the requirement of outdoor use, when the contents of polysaccharide in the adhesives were 40%. Therefore, this study may provide a facile and cost‐effective approach to prepare a high‐performance soy protein‐based adhesive. [ABSTRACT FROM AUTHOR]

Ischemic stroke is a leading cause of death and disability worldwide. Post‐ischemia, microglia respond immediately to the alternations in neuronal activity and mediate inflammation. Toll‐like receptor 4 (TLR4) plays a key role in this phenomenon. To explore the effect of loureirin C, an effective compound from Chinese Dragon's blood, on ischemic stroke, Sprague–Dawley rats were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) with/without intragastric administration of loureirin C (7, 14, and 28 mg/kg). Loureirin C alleviated MCAO/R‐induced brain impairment evaluated by neurological scores (p < 0.001), brain water content (p < 0.001), and cerebral infarct volume (p = 0.001). The neuroprotective (p < 0.001) and inhibitory effects on microglial activation (p < 0.001) of loureirin C were revealed by immunofluorescence. Rescue studies with TLR4 overexpression in BV‐2 microglia showed that the antiinflammatory effect of loureirin C was attributable to the inhibition of TLR4 protein expression. Moreover, co‐immunoprecipitation assays showed that the binding of Triad3A, an E3 ubiquitin ligase of TLR4, was increased by loureirin C (p = 0.003). Our study demonstrates that loureirin C could be a promising therapeutic agent for the management of ischemic stroke by inhibiting microglial activation, potentially by Triad3A‐mediated promotion of TLR4 ubiquitination and degradation. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the most promising green technologies to utilize solar energy for clean energy achievement and environmental governance, such as artificial photosynthesis, water splitting, pollutants degradation, etc. Despite decades of research, the performance of photocatalysis still falls far short of the requirement of 5% solar energy conversion efficiency. Combining photocatalysis with the other physical fields has been proven to be an efficient way around this barrier which can improve the performance of photocatalysis remarkably. This review will focus on the recent advances in photocatalysis coupling by external physical fields, including Thermal-coupled photocatalysis (TCP), Mechanical-coupled photocatalysis (MCP), and Electromagnetism-coupled photocatalysis (ECP). In this paper, coupling mechanisms, materials, and applications of external physical fields are reviewed. Specifically, the promotive effect on photocatalytic activity by the external fields is highlighted. This review will provide a detailed and specific reference for photocatalysis coupling by external physical fields in a deep-going way. [ABSTRACT FROM AUTHOR]

Solid-state photochemical reactions of olefinic compounds have been demonstrated to represent powerful access to organic cyclic molecules with specific configurations. However, the precise control of the stereochemistry in these reactions remains challenging owing to complex and fleeting configuration transformations. Herein, we report a unique approach to control the regiospecific configurations of C = C groups and the intermediates by varying temperatures in multiple-step thermal/photoinduced reactions, thus successfully realizing reversible ring closing/opening changes using a single-crystal coordination polymer platform. All stereochemical transitions are observed by in situ single-crystal X-ray diffraction, powder X-ray diffraction and infrared spectroscopy. Density functional theory calculations allow us to rationalize the mechanism of the synergistic thermal/photoinduced transformations. This approach can be generalized to the analysis of the possible configuration transformations of functional groups and intermediates and unravel the detailed mechanism for any inorganic, organic and macromolecular reactions susceptible to incorporation into single-crystal coordination polymer platforms. Solid-state photochemical reactions of olefinic compounds provide access to organic cyclic molecules with specific configurations but the precise control of the stereochemistry in these reactions remains challenging. Here, the authors demonstrate control of the regiospecific configurations of C=C groups and the intermediates by varying temperatures in multi-step thermal and photoinduced ring opening and closing reactions using a single-crystal coordination polymer platform. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) eradication plays a crucial role in gastric cancer prevention, but the antimicrobial resistance of H. pylori is obstructing this elimination process. In this study, we developed nanoclusters (NCs) from Zn0.3Fe2.7O4 nanoparticles using a poly(ethylene glycol)-b-poly(ε-caprolactone)-based nanocarrier as an innovative antibiotic-independent H. pylori management. Results: The nanocluster showed minimal toxicity and maximal biocompatibility. With a low concentration (50 µg/mL) of NCs under a short time period (~ 2 min) of near-infrared (808 nm) irradiation, we kept the culture medium temperature to 41 °C for 20 min with continuous irradiation. The heated NCs exhibited efficient photothermal effects and resulted in an excellent inhibition of H. pylori growth, adhesion and ability to induce vacuolization in eukaryotic cells in in vitro investigation. Transmission electron microscopy showed a dramatic morphologic change after NCs photothermia on H. pylori, including cell wall and membrane rupture, as well as ribosome damage. Besides, levofloxacin and clarithromycin resistance was decreased after photothermal treatment in H. pylori NCTC 11637 and/or clinical strains, however metronidazole resistance was unchanged. We also discovered a significant decrease in the biofilm formation of H. pylori under the NCs-based photothermal application, while efflux pump function was unchanged. Conclusions: Based on this novel NCs-based photothermal approach, we were able to demonstrate in vitro a significant inhibition of both H. pylori growth and molecular toxicity, and its improvement in antibiotic sensitivity alone with the eradication of H. pylori biofilms previously believed to be tolerant to conventional antibiotics. [ABSTRACT FROM AUTHOR]

In pulsed electromagnetic field tumor ablation, a bipolar nanosecond pulsed electric field has obvious therapeutic advantages. This article proposes a bipolar linear transformer drive (LTD) source circuit topology with a self-triggering H-bridge for this application. In this topology, in the absence of a magnetic core reset circuit, high-frequency bipolar pulse output is realized by introducing an H-bridge while keeping the circuit structure simple. A self-triggered H-bridge is formed by cleverly introducing a self-triggered circuit in the H-bridge, which reduces the difficulty of circuit control. There are only two main control signals, and the sources of all the main control switches share the same ground. The self-triggered switches are self-triggered through the energy-taking capacitor, which improves the stability of the switch control. Theoretical analysis and simulation results demonstrated the theoretical feasibility of the above-mentioned topology; thus, an experimental prototype was built to test the key parameters. The entire prototype adopts a modular design, and each module consists of only four self-triggering H-bridges and one nanocrystalline magnetic core. The key parameters of the final designed prototype are as follows: voltage amplitude of ±4 kV, pulse width of 60–260 ns, pulse rising edge of approximately 11 ns, continuous operation at a maximum frequency of 10 kHz, and output of 500 kHz high-frequency nanosecond pulse. [ABSTRACT FROM AUTHOR]

An ultrasensitive "signal-off–on" electrochemiluminescence (ECL) biosensor is constructed based on f1-TiO2/g-C3N4/PDA for thrombin detection. The flower-like titanium dioxide (f1-TiO2) has a huge specific surface area, which can not only increase the capacity of 2D graphite-like carbon nitride (g-C3N4) layer, but also promote the action of coreactants, and the ECL intensity of the electrode modified with f1-TiO2/g-C3N4/PDA is 3.5 times higher than the electrode modified with g-C3N4/PDA. The carboxylated thrombin aptamer (sDNA) is incubated onto the modified electrode by amide bond; then, the complementary strand of thrombin aptamer (tDNA) modified with ferrocene is connected to the electrode surface by complementary base pairing with sDNA. Due to the ferrocene can quench the ECL of g-C3N4, the ECL signal decreases, while the ECL signal is restored in the presence of the target thrombin (TB). When K2S2O8 and H2O2 are used as a co-reactant, the ECL aptasensor for TB detection is constructed with a concentration variation from 10−11 to 10−5 M, which has a excellent sensitivity, and the detection limit is 8.9 × 10−12 M. It also shows good specificity, reproducibility, and stability. This novel ECL aptasensor has potential application in human thrombin assay. [ABSTRACT FROM AUTHOR]

Background: Tumor cells tend to utilize glycolysis rather than aerobic respiration even under aerobic conditions. OVOL2, an inhibitory C2H2 zinc finger transcription factor, is a potential tumor suppressor in cancers. However, the association between OVOL2 and tumor energy metabolism is unknown. Methods: Western blotting was used to determine the expression of OVOL2 in different non-small cell lung cancer (NSCLC) cell lines and mouse models. The metabolic parameters in NSCLC cells following overexpression or knockdown OVOL2 were examined. To define the mechanism by which OVOL2 regulates aerobic glycolysis, interacting protein of OVOl2 and downstream molecular events were identified by luciferase assay and co-immunoprecipitation. We documented the regulatory mechanism in mouse xenograft models. Finally, clinical relevance of OVOL2, NF-κB signaling and GLUT1 was measured by immunostaining. Results: OVOL2 is downregulated in NSCLC and overexpression of OVOL2 inhibits the survival of cancer cells. Moreover, OVOL2 directly binds to P65 and inhibits the recruitment of P300 but facilitates the binding of HDAC1 to P65, which in turn negatively regulates NF-κB signaling to suppress GLUT1 translocation and glucose import. In contrast, OVOL2 expression is negatively regulated by NF-κB signaling in NSCLC cells via the ubiquitin–proteasome pathway. Re-expression of OVOL2 significantly compromise NF-κB signaling-induced GLUT1 translocation, aerobic glycolysis in NSCLC cells and mouse models. Immunostaining revealed inverse correlations between the OVOL2 and phosphorylated P65 levels and between the OVOL2 and membrane GLUT1 levels, and a strong correlation between the phosphorylated P65 and membrane GLUT1 levels. Conclusions: These results suggest a regulatory circuit linking NF-κB and OVOL2, which highlights the role of NF-κB signaling and OVOL2 in the modulation of glucose metabolism in NSCLC. 5S647uSA4FfDHArbVFhiZ4 Video Abstract [ABSTRACT FROM AUTHOR]

Four Cd(II)/diene coordination polymers (CPs) with similar 1D chain motifs exhibit different photosalient (PS) behaviours in response to UV light. The [2+2] photoreaction between the C＝C groups within these CPs results in diverse PS behaviours of their crystals with different C＝C pair arrangements. The interesting PS behaviours of these CPs can be applied in design and fabrication of advanced photoactuating materials. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons are among persistent organic pollutants and incomplete combustion of hydrocarbons during petroleum processing activities may cause polycyclic aromatic hydrocarbons contamination in the surrounding area. For the first time in Morgah, Rawalpindi, Pakistan, three targeted polycyclic aromatic hydrocarbons i.e. naphthalene, phenanthrene, and pyrene were estimated from surroundings of an oil refinery. Samples were collected simultaneously in soil, water, and leaves of Melia azedarach L., a widely grown tree species in the sampling area, along different selected sites of main drainage coming out of the refinery. Among three polycyclic aromatic hydrocarbons, pyrene was observed in maximum concentration (24.31 mg/kg in soil) among all selected environmental media and studied compounds showed a dynamic behavior in context of accumulation at different sampling points. There was a significant effect of distance, from petroleum refining area on polycyclic aromatic hydrocarbons levels in soil, water and plant leaves. Our findings provide conclusive evidence that location of an oil refinery has attributed to high polycyclic aromatic hydrocarbons contamination in selected study area which can pose significant risk to general environment and to the public. [ABSTRACT FROM AUTHOR]

Four structurally diverse coordination polymers 1–4 (CP1–CP4) were designed and constructed from Cd(II) ions and various carboxyl ligands (H2oba, 4,4′-oxydibenzoic acid; H2bpa, (E)-4,4′-(ethene-1,2-diyl)dibenzoic acid; H2pbda, 4,4′-((1,3-phenylenebis(methylene))bis(oxy))dibenzoic acid) and the alkene containing ligand (CH3-bpeb, 4,4′-((1E,1′E)-(2,5-dimethyl-1,4-phenylene)bis(ethene-2,1-diyl))dipyridine). CP1–CP4 possess Cd2 binuclear secondary building units (SBUs). The geometry of the dicarboxylate ligands and the reaction conditions determined the final structure with a variety of motifs. CP1 possesses an interdigitated 2D structure, while CP2 consists of a 1D channel-like motif with isolated CH3-bpeb molecules embedded in the channels. The solid-state structure of CP3 consists of two unique layers interpenetrated to form a 2D + 2D → 2D polycatenated backbone, while a 1D channel-like motif filled by isolated CH3-bpeb molecules was observed for CP4. In all four coordination polymers pairs of CH3-bpeb molecules were bound or encapsulated by the Cd2 secondary building units at an appropriate distance and orientation for solid-state [2 + 2] photodimerization of one pair of C＝C bonds. Desolvation of CP3 with heat resulted in a decrease in solid-state fluorescence and a slowing of the rate of solid-state photodimerization. [ABSTRACT FROM AUTHOR]

Activating basal plane inert sites will endow MoTe2 with prominent hydrogen evolution reaction (HER) catalytic capability and arouse a new family of HER catalysts. Herein, we fabricated single MoTe2 sheet electrocatalytic microdevice for in situ revealing the activated basal plane sites by vacancies introducing. Through the extraction of electrical parameters of single MoTe2 sheet, the in-plane and interlayer conductivities were optimized effectively by Te vacancies due to the defect levels. More deeply, Te vacancies can induce the delocalization of electrons around Mo atoms and shift the d-band center, as a consequence, facilitate the adsorption of H from the catalyst surface for HER catalysis. Benefiting by the coordinated regulation of band structure and local charge density, the overpotential at −10 mA·cm−2 was reduced to 0.32 V after Te vacancies compared to 0.41 V for the basal plane sites of same MoTe2 nanosheet. Meanwhile, the insights gained from single nanosheet electrocatalytic microdevice can be applied to the improved HER of the commercial MoTe2 power. That the in situ testing of the atomic structure-electrical behavior-electrochemical properties of a single nanosheet before/after vacancies introducing provides reliable insight to structure-activity relationships. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is an autoimmunity-related chronic demyelination disease of the central nervous system (CNS), causing young disability. Currently, highly specific immunotherapies for MS are still lacking. Programmed cell death 1 (PD-1) is an immunosuppressive co-stimulatory molecule, which is expressed on activated T lymphocytes, B lymphocytes, natural killer cells, and other immune cells. PD-L1, the ligand of PD-1, is expressed on T lymphocytes, B lymphocytes, dendritic cells, and macrophages. PD-1/PD-L1 delivers negative regulatory signals to immune cells, maintaining immune tolerance and inhibiting autoimmunity. This review comprehensively summarizes current insights into the role of PD-1/PD-L1 signaling in MS and its animal model experimental autoimmune encephalomyelitis (EAE). The potentiality of PD-1/PD-L1 as biomarkers or therapeutic targets for MS will also be discussed. [ABSTRACT FROM AUTHOR]

Oxidative stress has been proven to play a critical role in the pathogenesis of neuronal injury. As a novel adipocytokine, omentin is produced by visceral adipose with insulin sensitizing effects and has been revealed to possess anti-inflammatory effects. However, the possible effect of omentin on oxidative stress remains unknown. The present study aimed to detect the potential protective effect of omentin against hydrogen peroxide (H2O2)-induced cytotoxicity of PC12 cells. The results showed that no cytotoxic effect was shown in PC12 cells co-cultured with omentin alone at a concentration of 50–1000 ng/mL. The CCK8 and TUNEL assays suggested that omentin could remarkably attenuate apoptosis induced by 100 μM H2O2. The PCR and western blotting showed that the expression levels of Bax was significantly inhibited by omentin via the upregulation of miR-128-3p at its 3′-UTR. Taken together, these results indicated that omentin protects PC12 cells against H2O2-induced apoptosis, and further studies need to be conducted before utilization in the clinic for the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Poor efficacy and low electrical safety are issues in the treatment of tumours with pulsed magnetic fields (PMFs). Based on the cumulative effect of high-frequency pulses and the enhanced perforation effect of targeted nanoparticles, this article proposes for the first time a new method that combines high-frequency nanosecond-pulsed magnetic fields (nsPMFs) with folic acid-superparamagnetic iron oxide nanoparticles (SPIONs-FA) to kill tumour cells. After determining the safe concentration of the targeted iron oxide nanoparticles, CCK-8 reagent was used to detect the changes in cell viability after utilising the combined method. After that, PI macromolecular dyes were used to stain the cells. Then, the state of the cell membrane was observed by scanning electron microscopy, and other methods were applied to study the cell membrane permeability changes after the combined treatment of the cells. It was finally confirmed that the high-frequency PMF can significantly reduce cell viability through the cumulative effect. In addition, the targeted iron oxide nanoparticles can reduce the magnetic field amplitude and the number of pulses required for the high-frequency PMF to kill tumour cells in vitro through magnetoporation. The objective of this research is to improve the electrical safety of the PMF with the use of nsPMFs for the safe, efficient and low-intensity treatment of tumours. [ABSTRACT FROM AUTHOR]

In a real-world network confrontation process, attack and defense actions change rapidly and continuously. The network environment is complex and dynamically random. Therefore, attack and defense strategies are inevitably subject to random disturbances during their execution, and the transition of the network security state is affected accordingly. In this paper, we construct a network security state transition model by referring to the epidemic evolution process, use Gaussian noise to describe random effects during the strategy execution, and introduce a random disturbance intensity factor to describe the degree of random effects. On this basis, we establish an attack-defense stochastic differential game model, propose a saddle point equilibrium solution method, and provide an algorithm to select the optimal defense strategy. Our method achieves real-time defense decision-making in network attack-defense scenarios with random disturbances and has better real-time performance and practicality than current methods. Results of a simulation experiment show that our model and algorithm are effective and feasible. [ABSTRACT FROM AUTHOR]

Asian summer monsoon (ASM) variability and its long-term ecological and societal impacts extending back to Neolithic times are poorly understood due to a lack of high-resolution climate proxy data. Here, we present a precisely dated and well-calibrated treering stable isotope chronology from the Tibetan Plateau with 1- to 5-y resolution that reflects high- to low-frequency ASM variability from 4680 BCE to 2011 CE. Superimposed on a persistent drying trend since the mid-Holocene, a rapid decrease in moisture availability between ~2000 and ~1500 BCE caused a dry hydroclimatic regime from ~1675 to ~1185 BCE, with mean precipitation estimated at 42 ± 4% and 5 ± 2% lower than during themid-Holocene and the instrumental period, respectively. This second-millennium-BCE megadrought marks the mid-to late Holocene transition, during which regional forests declined and enhanced aeolian activity affected northern Chinese ecosystems. We argue that this abrupt aridification starting ~2000 BCE contributed to the shift of Neolithic cultures in northern China and likely triggered human migration and societal transformation. [ABSTRACT FROM AUTHOR]

Although tremendous efforts have been paid on electrocatalysts toward efficient electrochemical hydrogen generation, breakthrough is still highly needed in the design and synthesis of wonderful non-precious-metal electrocatalyst. Herein, a nanovilli Ni2P electrode, which with superaerophobic and superhydropholic can significantly facilitate the mass and electron transfer was constructed via a facial morphology control strategy. Meanwhile, the substitution of sluggish oxygen evolution with urea oxidation, lowering the two-electrode cell voltage to only 1.48 volts to achieve a current density of 10 mAcm−2. Thus, the as-constructed electrode achieves the operation of hydrogen generation by an AA battery. This work sheds new light on the exploration of other high-efficient electrocatalysts for hydrogen generation by using intermittent clean energy. [ABSTRACT FROM AUTHOR]

High quality Zn0.5CoxFe2.5 – xO4 (x = 0, 0.05, 0.1, 0.15) serial magnetic nanoparticles with single cubic structures were prepared by the modified thermal decomposition method, and Zn0.5CoxFe2.5 – xO4/SiO2 composite magnetic nanoparticles were prepared by surface modification of SiO2. The magnetic anisotropy of the sample increases with the increase of the doping amount of Co2+. When the doping amount is 0.1, the sample shows the transition from superparamagnetism to ferrimagnetism at room temperature. In the Zn0.5CoxFe2.5 – xO4/SiO2 serial samples, the maximum value of specific loss power (SLP) with 1974 W/gmetal can also be found at doping amount of x = 0.1. The composite nanoparticles are expected to be an excellent candidate for clinical magnetic hyperthermia. [ABSTRACT FROM AUTHOR]