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Electrocatalytic N2 reduction reaction (eNRR) has been deemed as an alternative approach to the Haber‐Bosch (H‐B) process for ammonia (NH3) production, but it remains a huge challenge. Here jet plasma oxidation of N2 is reported in air into NOx and subsequently NO2− coupling with electrochemical NO2− reduction reaction (pN2─eNO2−RR) over PdNi alloying nanoparticles on N‐doped carbon nanotubes (PdNi/N‐CNTs) for NH3 synthesis. The results demonstrate that the jet plasma reactor possesses excellent gas reforming capacity to achieve the largest NO2− yield rate of 30.46 mmol h−1 with a low energy consumption of 2.66 kWh molN−1. For subsequent eNO2−RR, PdNi/N‐CNTs can afford an NH3 yield of 34.96 mg h−1 mgcat.−1 and a faradaic efficiency (FE) of 98.21% at −0.38 and 0.02 V (vs RHE), respectively. In situ spectroscopic characterizations combined with theoretical calculations unveil that PdNi/N‐CNTs provide Pd and Ni dual active sites, enabling NO2− activation on the Ni site and active H* provision on the Pd site to facilitate eNO2−RR. A cascade pN2‐eNO2−RR system is constructed for sustainable NH3 production, achieving a stable NH3 yield rate of 25.56 mmol h−1, an average FE >85%, as well as NOx to NH3 conversion efficiency of 44.62% at constant ampere‐level current with finally collection of gram‐level (NH4) 2SO4 product. [ABSTRACT FROM AUTHOR]

This study intends to inspect the effects of acute aerobic exercise (AE) on resting state functional connectivity (RSFC) in motor cortex of college students and the moderating effect of fitness level. Methods: 20 high fitness level college students and 20 ordinary college students were recruited in public. Subjects completed 25 min of moderate- and high-intensity acute aerobic exercise respectively by a bicycle ergometer, and the motor cortex's blood oxygen signals in resting state were monitored by functional Near Infrared Spectroscopy (fNIRS, the Shimadzu portable Light NIRS, Japan) in pre- and post-test. Results: At the moderate intensity level, the total mean value of RSFC pre- and post-test was significantly different in the high fitness level group (pre-test 0.62 ± 0.18, post-test 0.51 ± 0.17, t(19) = 2.61, p = 0.02, d = 0.58), but no significant change was found in the low fitness level group. At the high-intensity level, there was no significant difference in the difference of total RSFC between pre- and post-test in the high and low fitness group. According to and change trend of 190 "edges": at the moderate-intensity level, the number of difference edges in the high fitness group (d = 0.58, 23) were significantly higher than those in the low fitness group (d = 0.32, 15), while at high-intensity level, there was a reverse trend between the high fitness group (d = 0.25, 18) and the low fitness group (d = 0.39, 23). Conclusions: moderate-intensity AE can cause significant changes of RSFC in the motor cortex of college students with high fitness, while high fitness has a moderating effect on the relationship between exercise intensity and RSFC. RSFC of people with high fitness is more likely to be affected by AE and show a wider range of changes. [ABSTRACT FROM AUTHOR]

Background: Gut microbiota could affect the onset and development of vascular cognitive impairment (VCI) through modulating metabolic and immune pathways. However, the vascular mechanisms involved remain unclear. Objective: To investigate the gut microbiota associated with VCI and examine the mediating effects of regional cerebral blood flow (CBF) to explore potential therapeutic targets for VCI. Methods: This prospective study enrolled patients with VCI (n = 16) and healthy controls (n = 18) from the Chinese Imaging, Biomarkers, and Lifestyle study between January 1 and June 30, 2022. The gut microbiota composition and diversity were determined by 16 S ribosomal RNA gene sequencing. The association between gut microbiota and Montreal Cognitive Assessment (MoCA) scores was determined using Spearman's correlation analysis. Regional CBF was calculated using pseudo-continuous arterial spin labeling. The mediating effects of regional CBF on the relationship between specific gut microbiota and cognition in VCI were investigated using mediation analysis. Results: Compared to healthy controls, patients with VCI had significantly greater abundance of Bifidobacterium, Veillonella, R uminococcus gnavus , Fusobacterium, and Erysipelatoclostridium and smaller abundance of Collinsella. The abundance of Ruminococcus gnavus was negatively associated with MoCA scores in patients with VCI, with the CBF in the left hypothalamus, right hypothalamus, and left amygdala accounting for 63.96%, 48.22%, and 36.51%, respectively, of this association after adjusting for confounders. Conclusions: Ruminococcus gnavus is associated with cognition in VCI, which is strongly mediated by CBF in the bilateral hypothalamus and left amygdala. These findings highlight the potential regulatory roles of nutrition and metabolism-related areas of the brain in VCI. [ABSTRACT FROM AUTHOR]

The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams. As a result, massive surface melting events of the ice shelf are occurring more frequently, which puts the West Antarctica Ice Sheet at greater risk of degradation. This study shows the connection between surface melting and the prominent intrusion of warm and humid air flows from lower latitudes. By applying the Climate Feedback-Response Analysis Method (CFRAM), the temporal surge of the downward longwave (LW) fluxes over the surface of the Ross Ice Shelf (RIS) and adjacent regions are identified for four historically massive RIS surface melting events. The melting events are decomposed to identify which physical mechanisms are the main contributors. We found that intrusions of warm and humid airflow from lower latitudes are conducive to warm air temperature and water vapor anomalies, as well as cloud development. These changes exert a combined impact on the abnormal enhancement of the downward LW surface radiative fluxes, significantly contributing to surface warming and the resultant massive melting of ice. [ABSTRACT FROM AUTHOR]

Protein‐protein interactions (PPIs) play critical roles in almost all cellular signal transduction events. Characterization of PPIs without interfering with the functions of intact cells is very important for basic biology study and drug developments. However, the ability to profile PPIs especially those weak/transient interactions in their native states remains quite challenging. To this end, many endeavors are being made in developing new methods with high efficiency and strong operability. By coupling with advanced fluorescent microscopy and mass spectroscopy techniques, these strategies not only allow us to visualize the subcellular locations and monitor the functions of protein of interest (POI) in real time, but also enable the profiling and identification of potential unknown interacting partners in high‐throughput manner, which greatly facilitates the elucidation of molecular mechanisms underlying numerous pathophysiological processes. In this review, we will summarize the typical methods for PPIs identification in living cells and their principles, advantages and limitations will also be discussed in detail. [ABSTRACT FROM AUTHOR]

Objective: This study inspects difference of resting state functional connectivity (RSFC) of motor cortex between athletes and ordinary college students and the test‐retest reliability of RSFC. Methods: Twenty high fitness level college students (high fitness group) and 20 ordinary college students (control group) were recruited. The motor cortical blood oxygen signals in resting states were monitored by functional near infrared spectroscopy (fNIRS). RSFCs of brain signals were preprocessed and calculated by FC‐NIRS software. RSFC results of test‐retest reliability were evaluated by intra‐class correlation coefficient (ICC). Results: Total RSFC (HbO signal) was significantly different between high fitness group (0.62 ± 0.04) and low fitness group (0.81 ± 0.04) (p <.05). Significant differences were found between the groups (HbO signal) in 50 edges among the 190 edges of motor cortex (14 edges after FDR corrected). At three hemoglobin concentrations, mean of group‐level ICC (C, 1) for total RSFC in two groups was 0.40 ± 0.10, whereas the mean of group‐level ICC (C, k) was 0.57 ± 0.11, depicting "fair" reliability. The mean of group‐level ICC (C, 1) of 190 "edges" was 0.88 ± 0.06, whereas mean of ICC (C, k) was 0.94 ± 0.03, exhibiting "excellent" reliability. Conclusion: Fitness level is the factor causing specific changes in RSFC strength of motor cortex that can be utilized as biomarker for evaluating the fitness level. [ABSTRACT FROM AUTHOR]

Tea plant (Camellia sinensis) has very long history of cultivation and abundant germplasm resources in China. Purple bud is a characteristic variety, which has attracted the attention of breeding researchers because it accumulated a large number of anthocyanins naturally. In many species, R2R3-MYB transcription factors (TFs) were proved to be involved in the regulation of anthocyanin biosynthesis. Research on anthocyanin metabolism has been relatively clear in some species, but that needs to be further elucidated in tea plants. In this research, an R2R3-MYB transcription factor CsMYB113 related to the anthocyanin accumulation regulation was identified from tea plants. Spatial and temporal expression analysis revealed differential expression of CsMYB113 among different tissues and organs, with highest expression occurring in the roots. Subcellular localization assays showed that CsMYB113 localized in the nucleus. Ectopic expression of CsMYB113 increased pigmentation and anthocyanin contents by the upregulation of the expression levels of genes in anthocyanin biosynthesis pathway among different tissues of Arabidopsis. Moreover, transient overexpression of 35S::CsMYB113 in tea plant increased the anthocyanin contents in the leaves. Our results indicated that CsMYB113 plays important role in the anthocyanin biosynthesis regulation in tea plants. It will also provide useful candidate gene for the modification of anthocyanin metabolism by genetic engineering in plants. [ABSTRACT FROM AUTHOR]

Reverse homodigital dorsoradial flap (RHDF) of the thumb has become a qualified option for the reconstruction of thumb tissue defects. However, the sensory recovery of the flap in long term is still unknown. Therefore, this study focused on the sensory recovery of RHDFs for the coverage of thumb in hand after a long-term follow-up. From January 2010 to March 2011, 18 patients (14 men and four women) were treated consecutively with an RHDF. All the patients were followed up two times. The pain and cold intolerance of the flap were self-reported by the patients. The sensory recovery of the flap was evaluated using Semmes–Weinstein (SW) monofilament, moving two-point discrimination (M-2PD) and static two-point discrimination (S-2PD) tests. The average times of the first and second follow-up were 39 ± 4 and 88 ± 6 months, respectively. The mean value of SW monofilament sensitivity score and M-2PD at first follow-up was significantly higher than that of the second follow-up and contralateral thumb. The mean value of S-2PD at the second follow-up was significantly lower than that of the first follow-up and higher than that of the contralateral thumb. The cold intolerance severity score (CISS) at the first follow-up was higher than that at the second follow-up. No significant difference was found in terms of the pain between the two follow-ups. RHDFs without nerve coaptation for thumb coverage could obtain good sensory recovery after a long-term follow-up. Abbreviations: RHDF: reverse homodigital dorsoradial flap; CISS: cold intolerance severity score; SW: Semmes–Weinstein monofilament sensitivity score; M-2PD: moving two-point discrimination; S-2PD: static two-point discrimination; VAS: visual analog scale. [ABSTRACT FROM AUTHOR]

The self-noise level of a seismometer can determine the performance of the seismic instrument and limit the ability to use seismic data to solve geoscience problems. Accurately measuring and simultaneously comparing the self-noise models from different types of seismometers has long been a challenging task due to the constraints of observation conditions. In this paper, the self-noise power spectral density (PSD) values of nine types of seismometers are calculated using four months of continuous seismic waveforms from Malingshan seismic station, China, and nine self-noise models are obtained based on the probability density function (PDF) representation. For the seismometer STS-2.5, the self-noise levels on the horizontal channels (E–W and N–S) are significantly higher than that on the vertical channel (U–D) in the microseism band (0.1 Hz to 1 Hz), which is a computing bias caused by the misalignment between the sensors in the horizontal direction, while the remarkably elevated noise on the horizontal channels at the low frequencies (<0.6 Hz) may originate from the local variation of atmospheric pressure. As for the very broadband seismometers Trillium-Horizon-120 and Trillium-120PA, and the ultra-broadband seismometers Trillium-Horizon-360 and CMG-3T-360, there is a trade-off between the microseism band range and low-frequency range in the PSD curves of the vertical channel. When the level of self-noise in the microseism band is high, the self-noise at low frequencies is relatively low. Although compared with the other very broadband seismometers, the self-noise level of the vertical component of the STS-2.5 is 3 dB to 4 dB lower at frequencies less than 1 Hz, the self-noise level of the STS-2.5 at high frequencies (>2 Hz) is slightly higher than others. From our observations, we conclude that the nine seismometers cannot reach the lowest noise level in all frequency bands within the working range. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass is considered the most abundant and renewable feedstock for biobased butyric acid production. However, the furan derivatives (FAs, mainly furfural and 5-hydroxymethylfurfural) generated from the pretreatment of lignocellulose severely inhibit the growth of Clostridium tyrobutyricum, which is the best strain for producing butyric acid. The tolerance mechanism of C. tyrobutyricum to FAs has not been investigated thus far. Here, the response of C. tyrobutyricum ATCC 25755 to FA challenge was first evaluated by using comprehensive transcriptional analysis. The results indicated that the genes related to membrane transport, heat shock proteins, and transcriptional regulation were upregulated under FA stress. However, the expression of almost all genes encoding reductases was not changed, and only the ad gene CTK_RS02625 and the bud gene CTK_RS07810 showed a significant increase of ~ 1.05-fold. Then, the enzyme activity assays indicated that BUD could catalyze the reduction of FAs with relatively low activity and that AD could not participate in the conversion of FAs, indicating that the inability to rapidly convert FAs to their low-toxicity alcohols may be the main reason for the low FA tolerance of C. tyrobutyricum. This research provides insights into the development of FA-tolerant strains, thereby enhancing the bioconversion of lignocellulosic biomass to butyric acid. Key points: • The response of C. tyrobutyricum to FAs was evaluated for the first time. • Genes encoding membrane transporters and heat shock proteins were triggered by FAs. • A lack of effective FA reductases leads to low FA tolerance in C. tyrobutyricum. [ABSTRACT FROM AUTHOR]

Perovskite LaFeO 3 with ABO 3 structure is regarded as a potential candidate in electromagnetic wave absorption, considering its unique dielectric-magnetic coupling loss mechanism. However, the limited attenuation ability of pristine LaFeO 3 restricts its further application. In this work, the dual doping strategy is carried out to improve the dielectric and magnetic loss capacity. Ca and Mn dual doped La 0.8 Ca 0.2 Fe 1-x Mn x O 3 are prepared by spray pyrolysis method. The minimum reflection loss (RL min) of La 0.8 Ca 0.2 Fe 0.2 Mn 0.8 O 3 reaches −52.3 dB with an effective absorption bandwidth (EAB) of 3.92 GHz at the fitting thickness of 2.08 mm. The enhancement of the dielectric loss mainly originates from strengthened dipole polarization induced by the Jahn-Teller distortion which is caused by Ca and Mn double doping. The magnetic loss can be attributed to the improvement of double-exchange between Fe3+ –O2- -Mn3+ and Mn3+ –O2- -Mn4+ owing to the introduction of Mn. This work provides new insights into regulating the electromagnetic wave absorption performance of perovskite. • Dual doped perovskite oxide La 0.8 Ca 0.2 Fe 1-x Mn x O 3 were synthesized via facile spray pyrolysis method. • The Jahn-Teller distortion is achieved by an A/B double-doped perovskite oxide strategy, and the conformational relationship between B–O properties and lattice distortion was investigated, the lattice distortion of LCFMO successfully enhanced the polarization and relaxation process. • Based on Zener's double exchange theory, the Fe3+/Mn4+- O -Mn3+ double exchange channel is constructed to enhance the magnetic loss, and the crystal structure and electron leaps work together to achieve the matching of dielectric and magnetic properties. [ABSTRACT FROM AUTHOR]

Electroadhesive grippers can be used to pick up a wide range of materials, and those with variable stiffness functionality can increase load capacity and strength. This paper proposes an electroadhesive gripper (VSEAF) with variable stiffness function and a simple construction based on low melting point alloys (LMPAs) with active form adaptation through pneumatic driving. Resistance wires provide active changing stiffness. For a case study, a three-fingered gripper was designed with three electroadhesive fingers of varied stiffness. It is envisaged that these electroadhesive grippers with variable stiffness would extend the preparation process and boost the use of electroadhesion in soft robot applications. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have garnered considerable attention due to their advantageous properties, including tunable bandgap, prominent carrier mobility, tunable response and absorption spectral band, and so forth. The above-mentioned properties ensure that 2D materials hold great promise for various high-performance infrared (IR) applications, such as night vision, remote sensing, surveillance, target acquisition, optical communication, etc. Thus, it is of great significance to acquire better insight into IR applications based on 2D materials. In this review, we summarize the recent progress of 2D materials in IR light emission device applications. First, we introduce the background and motivation of the review, then the 2D materials suitable for IR light emission are presented, followed by a comprehensive review of 2D-material-based spontaneous emission and laser applications. Finally, further development directions and challenges are summarized. We believe that milestone investigations of 2D-material-based IR light emission applications will emerge soon, which are beneficial for 2D-material-based nano-device commercialization. [ABSTRACT FROM AUTHOR]

In order to solve the difficult problem of deep learning-based robot vision tracking algorithm research and implementation, a deep learning-based target tracking algorithm and a classical tracking algorithm were proposed. It mainly uses the combination of traditional TLD algorithm and GOTURN algorithm to benefit from a large number of offline training data and updates the learner online, so that the whole system has better performance in real-time and accuracy. The results show that the performance of the TLD algorithm is poor regardless of the accuracy curve or the accuracy curve, and the performance of GOTURN-LD is significantly improved when the illumination changes. In the face of occlusion problem, the TLD algorithm shows strong robustness. Although GOTURN-LD is not very stable, its performance is better than GOTURN on the whole. [ABSTRACT FROM AUTHOR]

With the increasing proportion of wind turbines in power grids, they are required to have capabilities of active and efficient virtual inertial response to maintain grid frequency stability. However, the virtual inertial control methods currently used in doubly-fed induction generator (DFIG) units suffer from a secondary frequency drop (SFD) problem. Although the SFD can be inhibited by reducing the active power support strength of the DFIG units during inertia response, it will undoubtedly weaken the virtual inertia of the units. Therefore, how to eliminate the SFD while increasing the virtual inertia of the units is a worthy issue for studying. To solve this issue, a wind-storage combined virtual inertial control system based on quantization and regulation decoupling of active power increments is proposed in this paper. First, by setting the parameters of a proportional–differential (P-D) algorithm, the total active power increments required for virtual inertial response are quantified at the DFIG level. Secondly, a curve-shifting method based on the rate of change of frequency is adopted to adjust the active power output of the DFIG units. Finally, a battery energy storage system (BESS) is used to compensate for the power shortages of the units according to the quantized value of the active power increments. Simulations show that the control method can not only eliminate SFD but also effectively increase the system's virtual inertia. [ABSTRACT FROM AUTHOR]

With the development of power modules for high voltage, high temperature, and high power density, their size is becoming smaller, and the packaging insulation experiences higher electrical, thermal, and mechanical stress. Packaging insulation needs to meet the requirement that internal electric field, temperature, and mechanical stress should be as low as possible. Focusing on the coupling principles and optimization design among electrical, thermal, and mechanical stresses in the power module packaging insulation, a multi-objective optimization design method based on Spice circuit, finite element field numerical calculation, and multi-objective gray wolf optimizer (MOGWO) is proposed. The packaging insulation optimal design of a 1.2 kV SiC MOSFET half-bridge power module is presented. First, the high field conductivity characteristics of the substrate ceramic and encapsulation silicone of the packaging insulation material were tested at different temperatures and external field strengths, which provided the key insulation parameters for the calculation of electric field distribution. Secondly, according to the mutual coupling principles among electric–thermal–mechanical stress, the influence of packaging structure parameters on the electric field, temperature, and mechanical stress distribution of packaging insulation was studied by finite element calculation and combined with Spice circuit analysis. Finally, the MOGWO algorithm was used to optimize the electric field, temperature, and mechanical stress in the packaging insulation. The optimal structural parameters of the power module were used to fabricate the corresponding SiC MOSFET module. The fabricated module is compared with a commercial module by the double-pulse experiment and partial discharge experiment to verify the feasibility of the proposed design method. [ABSTRACT FROM AUTHOR]

• A circular pressure modulation approach for steerable ultrasonic propulsion of rigid objects is developed based on the simplified sector-array of focused transducers. • The general theory of ARF exerting on on-axis rigid spheres is derived in explicit formula for traditional and inclined focused fields based on acoustic scattering. • The ARF acting on on-axis spheres by focused fields exhibits an axial distribution of increasing followed by decreasing with the peak slightly beyond the focus. • Inclined propulsion is realized by adjusting the angle of power-on sources, with the maximum deflection angle determined by the F-number and element number of the sector-array. • This study provides an applicable technique for steerable propulsion of calculi using an ultrasonic power supply without the complex control in amplitude and phase for the sector-array. As a common disease of human urinary system, the high prevalence and incidence rate of renal calculus have brought heavy burden to society. Traditional ultrasonic lithotripsy struggles with the comprehensive elimination of residual fragments and may inadvertently inflict renal damage. Although focused ultrasound can propel stones by the acoustic radiation force (ARF) with minimal tissue damage and enhanced passage rate, it is still lack of the accurate control for calculi at different locations. A circular pressure modulation approach for steerable ultrasonic propulsion of rigid objects is developed based on a sector-array of focused transducers. The ARF exerted on on-axis rigid spheres (stones) is derived based on acoustic scattering. It is proved that the ARF of focused fields exhibits an axial distribution of increasing followed by decreasing with the peak slightly beyond the focus. As the sphere radius increases, the ARF exerted on spheres at the focus increases accordingly with a decreasing growth rate. Inclined propulsion can be realized by the circular binary pressure modulation with the deflection increased by expanding the angle of power-off sector sources. The maximum deflection angle approaching 60° is determined by the F-number and element number of the sector-array. Experimental propulsions of steel balls are conducted using an 8-element sector-array with motion trajectories captured by a high-speed camera. Distributions of the motion speed and acceleration for steel balls of different radii are calculated through image processing. The ARF of mN level and the deflection angle of 12° are demonstrated by the successful propulsion of steel balls. This research provides an effective and flexible approach of steerable stone propulsion using an ultrasonic power supply without the complex control in amplitude or phase and the high-precision motion of the sector-array, hence promoting the practical application in non-invasive treatment of stones. [ABSTRACT FROM AUTHOR]

Ni-based superalloys are widely used to manufacture the critical hot-end components of aviation jet engines and various industrial gas turbines. The analysis of Ni-based superalloys microstructures is an important research task during the design and development of superalloys. The material microstructure information can only be understood by experts in the long history. Image segmentation and recognition are developing techniques for accelerating the microstructure analysis automatically. Although deep learning techniques have achieved satisfactory performance, they usually suffer from generalization, i.e., performing worse on a new dataset. In this paper, a deep transfer learning method which just needs a small number of labeled images is proposed to perform the microstructure recognition on γ ′ phase. To evaluate the effectiveness, we homely prepare two Ni-based superalloys at temperatures 900 ° C and 1000 ° C, and manually annotate two datasets named as W-900 and W-1000. Experimental results demonstrate that the proposed method only needs 3 and 5 labeled images to achieve state-of-the-art segmentation accuracy during the transfer from W-900 to W-1000 and the transfer from W-1000 to W-900, while enjoying the advantage of fast convergence. In addition, a simple and effective software for the Ni-based superalloys microstructure recognition on γ ′ phase is developed to improve the efficiency of materials experts, which will greatly facilitate the design of new Ni-base superalloys and even other multicomponent alloys. [ABSTRACT FROM AUTHOR]

In order to improve the quality of remanufacturing assembly with uncertainty for the sustainability of remanufacturing industry, an error propagation model of the remanufacturing assembly process and its optimal control method are established. First, the state space model of error propagation is established by taking the work-in-process parameter errors of each process as the initial state of the procedure and the parameters of remanufactured parts and operation quantities as the input. Then, the quality control issue of remanufacturing assembly is transformed into a convex quadratic programming with constraints based on this model. Finally, the proposed method is used to control the remanufactured-crankshaft assembly quality. The experimental results show that the axial-clearance consistency and the crankshaft torque are improved, and the one-time assembly success rate of a remanufactured crankshaft is increased from 96.97%to 99.24%. This study provides a theoretical model and method support for the quality control of remanufacturing assembly and has a practical effect on improving the quality of remanufactured products. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides (AMPs), a part of the natural defence against pathogens, have been considered as alternative antibiotics to combat the increase of antimicrobial resistance (AMR). Given the advanced development of fluorescent probes, extensive research has been focussed on understanding the physiological processes of the interaction between AMPs and bacteria. To better guide the choice of suitable fluorescent reporters for the mechanism study of AMPs, in this review, we summarise a toolbox of commonly used fluorescent reporters for AMP studies, including intrinsic fluorescent reporters, conventional fluorophores, and recently developed aggregation-induced emission (AIE) fluorogens. This paper is a brief guide of commonly available fluorescent labelling methodologies to study the mechanisms of antimicrobial peptides (AMPs). [ABSTRACT FROM AUTHOR]

Cd is one of the most serious and harmful heavy metals in the world. Nanomaterials as a new passivating agent for heavy metals in soil have become a hot issue. But nanometer magnesium hydroxide application to heavy metal pollution in soils has not been reported. The laboratory culture experiments were conducted to study the effect of nanometer magnesium hydroxide and ordinary magnesium hydroxide (100, 200, and 300 mg kg−1) as cadmium passivators on soil cadmium form under different cadmium levels (1, 5, 10, and 15 mg kg−1). The results showed that the soil Cd distribution ratio of exchangeable Cd (EX‐Cd FDC) was 66.7% to 81.8% at cadmium levels of 1, 5, 10, and 15 mg kg−1, identifying it as the main form of soil cadmium. Soil EX‐Cd FDC reached the lowest level on the 14th day of culture. Addition of both nanometer magnesium hydroxide and ordinary magnesium hydroxide decreased the EX‐Cd FDC of the soil at each cadmium level. With increasing amount, the soil EX‐Cd FDC followed a decreasing trend. During the 0–28 days of culture, at the levels of 1, 5, 10, and 15 mg kg−1 cadmium, the EX‐Cd FDC of soil treated with nanometer magnesium hydroxide and ordinary magnesium hydroxide decreased by 11.4% to 67.7%, 7.8% to 37.2%, 7.7% to 36.4%, and 5.0% to 28.8% (nanometer magnesium hydroxide) and.5% to 49.5%,.6% to 15.0%, 1.0% to 18.1%, and.7% to 14.6% (common magnesium hydroxide), respectively, compared with control. Under the same application amount, nanometer magnesium hydroxide achieved a better effect than ordinary magnesium hydroxide in reducing soil EX‐Cd FDC. The antagonism between Cd and Mg competes for exchange sites during soil adsorption or Mg2+ forms hydroxy‐magnesium through OH− coordination in the soil via hydrolysis equilibrium. This facilitates the formation of precipitates, such as carbonates in Cd2+, and reduces active‐state cadmium in soil. The effect of nanometer magnesium hydroxide in passivating active cadmium on cadmium‐contaminated soil exceeds that of common magnesium hydroxide. [ABSTRACT FROM AUTHOR]

Primary anti‐phospholipid antibody syndrome (pAPS) is a multi‐organ autoimmune disease, and autoantibodies are involved in its pathogenesis. Follicular helper T cells (Tfh) and follicular regulatory T cells (Tfr) are critical for B cell maturation and antibody production, but their roles in pAPS remain unknown. We enrolled 32 pAPS patients and 23 healthy controls (HCs) and comprehensively analyzed circulating Tfh and Tfr, as well as their subsets, using flow cytometry. Clinical data including autoantibody levels were collected and their correlations with Tfh and Tfr subsets were analyzed. In addition, correlation analyses between B cell functional subsets and Tfh and Tfr were performed. Changes and potential effects of serum cytokines on Tfr and Tfh were further explored. We found the circulating Tfr was significantly decreased while Tfh and Tfh/Tfr ratios were increased in pAPS patients. Tfh2, inducible T cell co‐stimulator (ICOS)+ programmed cell death 1 (PD‐1)+ Tfh and Ki‐67+ Tfh percentages were elevated, while CD45RA−forkhead box protein 3 (FoxP3)hi, Helios+, T cell immunoglobulin and ITIM (TIGIT)+ and Ki‐67+ Tfr percentages were decreased in pAPS patients. New memory B cells and plasmablasts were increased and altered B cell subsets and serum autoantibodies were positively correlated with Tfh, Tfh2, ICOS+PD‐1+ Tfh cells and negatively associated with Tfr, CD45RA−FoxP3hi Tfr and Helios+ Tfr cells. In addition, pAPS with LA/aCL/β2GPI autoantibodies showed lower functional Tfr subsets and higher activated Tfh subsets. Serum interleukin (IL)‐4, IL‐21, IL‐12 and transforming growth factor (TGF)‐β1 were up‐regulated and associated with Tfh and Tfr subset changes. Our study demonstrates that imbalance of circulating Tfr and Tfh, as well as their functional subsets, is associated with abnormal autoantibody levels in pAPS, which may contribute to the pathogenesis of pAPS. [ABSTRACT FROM AUTHOR]

We reported metallic ruthenium (Ru) nanoparticles loaded on amino modified dendritic mesoporous silica microspheres (Ru/NH2‐DMSMs) for ammonia decomposition to hydrogen. The sizes of the loaded Ru nanoparticles on carrier are 2–3 nm, providing rich active sites for ammonia decomposition reaction. As a result, the obtained Ru/NH2‐DMSMs‐5.1 can afford almost ~100 % ammonia decomposition at 550 °C, due to the unique mesoporous structure of DMSMs inhibiting the aggregation of active Ru nanoparticles and enhancing the mass transport of ammonia. [ABSTRACT FROM AUTHOR]

During carbon fiber–reinforced plastic (CFRP) hole-making, exit damages such as burrs and delamination frequently occur. Some hole-making technologies are invented to cater to the demands of the high hole quality for CFRP laminates. To adequately eliminate the process-induced damages, a novel dill-milling tool is designed, and a series of drill-milling experiments are conducted on CFRP by using this novel drill-milling tool. Theoretical and experimental analyses of the drill-milling process and the performance of the novel drill-milling have been conducted. The result indicates that compared with the drilling process, using the new drill-milling process, the burrs can be thoroughly removed and the delamination can be reduced significantly, even removed. The changes of the hole quality and the exit damages are different with the variations of the helical milling parameters. Therefore, by comprehensive consideration, proper helical milling parameters should be chosen adequately. Furthermore, in theory, the right-handed helix angles βy should be raised, which is favorable for improving the hole accuracy and reducing the exit damages. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides (AMPs) are being intensively investigated as they are considered promising alternatives to antibiotics where their clinical efficacy is dwindling due to the emergence of antimicrobial resistance (AMR). Accompanying with the development of AMPs, a number of fluorescent probes have been developed to facilitate the understanding the modes of action of AMPs. These probes have been used to monitor the binding process, determine the working mechanism and evaluate the antimicrobial properties of AMPs. In particular, with the recent advance of aggregation‐induced emission (AIE) fluorophores, that show many advantageous properties over traditional probes, there is an increasing research interest in using AIE probes for AMP studies. In this review, we give an overview of AMP development, highlight the recent progress of using fluorescence probes in particularly AIE probes in the AMP field and propose the future perspective of developing potent antimicrobial agents to combat AMR. [ABSTRACT FROM AUTHOR]

Cationic antimicrobial peptides have been investigated for their potential use in combating infections by targeting the cell membrane of microbes. Their unique chemical structure has been investigated to understand their mode of action and optimize their dose–response by rationale design. One common feature among cationic AMPs is an amidated C-terminus that provides greater stability against in vivo degradation. This chemical modification also likely modulates the interaction with the cell membrane of bacteria yet few studies have been performed comparing the effect of the capping groups. We used maculatin 1.1 (Mac1) to assess the role of the capping groups in modulating the peptide bacterial efficiency, stability and interactions with lipid membranes. Circular dichroism results showed that C-terminus amidation maintains the structural stability of the peptide (α-helix) in contact with micelles. Dye leakage experiments revealed that amidation of the C-terminus resulted in higher membrane disruptive ability while bacteria and cell viability assays revealed that the amidated form displayed higher antibacterial ability and cytotoxicity compared to the acidic form of Mac1. Furthermore, 31P and 2H solid-state NMR showed that C-terminus amidation played a greater role in disturbance of the phospholipid headgroup but had little effect on the lipid tails. This study paves the way to better understand how membrane-active AMPs act in live bacteria. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is one of the greatest threats to human health that, by 2050, will lead to more deaths from bacterial infections than cancer. New antimicrobial agents, both broad-spectrum and selective, that do not induce AMR are urgently required. Antimicrobial peptides (AMPs) are a novel class of alternatives that possess potent activity against a wide range of Gram-negative and positive bacteria with little or no capacity to induce AMR. This has stimulated substantial chemical development of novel peptide-based antibiotics possessing improved therapeutic index. This review summarises recent synthetic efforts and their impact on analogue design as well as their various applications in AMP development. It includes modifications that have been reported to enhance antimicrobial activity including lipidation, glycosylation and multimerization through to the broad application of novel bio-orthogonal chemistry, as well as perspectives on the direction of future research. The subject area is primarily the development of next-generation antimicrobial agents through selective, rational chemical modification of AMPs. The review further serves as a guide toward the most promising directions in this field to stimulate broad scientific attention, and will lead to new, effective and selective solutions for the several biomedical challenges to which antimicrobial peptidomimetics are being applied. [ABSTRACT FROM AUTHOR]

Allium cepa is used for the prevention and treatment of hyperlipidemia‐related diseases such as atherosclerosis in the folk. This study was mainly aimed at investigating the effects of A. cepa extract (ACE) enriched in polyphenols on hyperlipidemia Sprague‐Dawley (SD) experiment rat models. The levels of total cholesterol (TC), triglyceride (TG), low‐density lipoprotein cholesterol (LDL‐C), high‐density lipoprotein cholesterol (HDL‐C), malondialdehyde (MDA), and superoxide dismutase (SOD) activity in serum and liver were measured using ELISA kits. In addition, hematoxylin‐eosin (HE) technique was used to observe the liver and the aortic arch pathology. Moreover, western blotting (WB) method was applied to analyze LDL receptor (LDLR) and 3‐hydroxy‐3‐methylglutaryl (HMG)‐CoA reductase (HMGCR) in liver. As a result, quercetin (2.42 mg/g DW) and isoquercitrin (4.60 mg/g DW) were the main constituents of ACE using HPLC analysis. Furthermore, ACE reduced the levels of TC, TG, LDL‐C, and MDA, and increased HDL levels and elevated SOD activity both in serum and liver in hyperlipidemic SD rats (p <.05). HE results showed that liver fat drops of the rats in ACE group were obviously decreased, and the lipid and foam cells of the aortic arch of the rats in ACE group were markedly ameliorated. WB results showed that ACE promoted the degradation of HMGCR and increased LDLR expression in liver (p <.05). In conclusion, ACE alleviated hyperlipidemia with downregulation of HMGCR and upregulation of LDLR. Practical applications: Atherosclerosis, a major cardiovascular disease, is the leading cause of mortality and morbidity in the developed countries. Moreover, accumulating data indicate that, during atherosclerosis development, hyperlipidemia is an important risk factor. To date, hyperlipidemia is mainly treated with hyperlipidemic agents including statins, in spite of the side effects and poor tolerance in some patients. In addition, Allium cepa is a medicinal and edible plant. Furthermore, A. cepa is used for the prevention and treatment of hyperlipidemia‐related diseases such as atherosclerosis in the folk. But the underlying mechanism is still unclear. In fact, this research showed that A. cepa extract (ACE) alleviated hyperlipidemia with downregulation of HMGCR and upregulation of LDLR, suggesting that ACE might be a potential option for hyperlipidemia as non‐statin lipid‐lowering agent. [ABSTRACT FROM AUTHOR]

Objectives. To assess the expression and clinical value of miR-19 in gastrointestinal malignancy. Setting. Embase, Web of Science, PubMed, and other databases were retrieved to screen out relevant studies until December 31, 2019. Participants. Gastrointestinal cancer patients with the description of miR-19 expression, as well as the correlation between miR-19 and clinicopathological characteristics or prognosis. Main Outcome Measures. Pooled odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI) was obtained to determine miR-19 expression in gastrointestinal malignancy and the association between miR-19 and patients' clinical characteristics and survival. Results. Thirty-seven studies were included in this study. miR-19 levels in gastrointestinal malignancy, especially in hepatocellular (OR = 4.88 , 95 % CI = 2.38 ‐ 9.99), colorectal (OR = 4.81 , 95 % CI = 2.38 ‐ 9.72), and pancreatic (OR = 5.12 , 95 % CI = 2.43 ‐ 10.78) cancers, were significantly overexpressed, and miR-19 was tightly related to some clinicopathological characteristics, such as lymph node metastasis (OR = 1.74 , 95 % CI = 1.05 ‐ 2.86). Although gastrointestinal cancer patients with low and high miR-19 expression had comparable OS (overall survival) and DFS (disease-free survival), subgroup analyses showed that patients with high miR-19 presented better DFS than those with low miR-19 in liver cancer (HR = 0.46 , 95 % CI = 0.30 ‐ 0.71). Conclusions. miR-19 might be a potential progression and prognostic biomarker for gastrointestinal malignancy. [ABSTRACT FROM AUTHOR]

Objectives. To assess the expression and clinical value of miR-19 in gastrointestinal malignancy. Setting. Embase, Web of Science, PubMed, and other databases were retrieved to screen out relevant studies until December 31, 2019. Participants. Gastrointestinal cancer patients with the description of miR-19 expression, as well as the correlation between miR-19 and clinicopathological characteristics or prognosis. Main Outcome Measures. Pooled odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI) was obtained to determine miR-19 expression in gastrointestinal malignancy and the association between miR-19 and patients' clinical characteristics and survival. Results. Thirty-seven studies were included in this study. miR-19 levels in gastrointestinal malignancy, especially in hepatocellular (OR = 4.88 , 95 % CI = 2.38 ‐ 9.99), colorectal (OR = 4.81 , 95 % CI = 2.38 ‐ 9.72), and pancreatic (OR = 5.12 , 95 % CI = 2.43 ‐ 10.78) cancers, were significantly overexpressed, and miR-19 was tightly related to some clinicopathological characteristics, such as lymph node metastasis (OR = 1.74 , 95 % CI = 1.05 ‐ 2.86). Although gastrointestinal cancer patients with low and high miR-19 expression had comparable OS (overall survival) and DFS (disease-free survival), subgroup analyses showed that patients with high miR-19 presented better DFS than those with low miR-19 in liver cancer (HR = 0.46 , 95 % CI = 0.30 ‐ 0.71). Conclusions. miR-19 might be a potential progression and prognostic biomarker for gastrointestinal malignancy. [ABSTRACT FROM AUTHOR]

The chemical formation of the peptide bond has long fascinated and challenged organic chemists. It requires not only the activation of the carboxyl group of an amino acid but also the protection of the Nα-amino group. The more than a century of continuous development of ever-improved protecting group chemistry has been married to dramatic advances in the chemical synthesis of peptides that, itself, was substantially enhanced by the development of solid-phase peptide synthesis by R. B. Merrifield in the 1960s. While the latter technology has continued to undergo further refinement and improvement in both its chemistry and automation, the development of the base-labile 9-fluorenylmethoxycarbonyl (Fmoc) group and its integration into current synthesis methods is considered a major landmark in the history of the chemical synthesis of peptides. The many beneficial attributes of the Fmoc group, which have yet to be surpassed by any other Nα-protecting group, allow very rapid and highly efficient synthesis of peptides, including ones of significant size and complexity, making it an even more valuable resource for research in the post-genomic world. This review charts the development and use of this Nα-protecting group and its adaptation to address the need for more green chemical peptide synthesis processes. Alternative deprotection reagents together with green solvents in modern SPPS strategies have contributed to the enduring popularity of the Nα-Fmoc group in the chemical synthesis of peptides. [ABSTRACT FROM AUTHOR]

During the measurement of spectral luminous efficiency function V λ , monochromatic visual stimuli of higher luminance can be obtained by narrow band optical filters with broad band light sources, compared to monochromators. However, the distortion of V λ is inevitably caused due to the bandwidth of the optical filters. In this paper, the effect of optical filters and light source spectra on the spectral luminous efficiency function V λ measurement is studied. Filters with different spectral transmittances and light sources with different spectral power distributions are considered in the model to simulate visual sensitivity experiment. Compared with real V λ , the distortion of the simulated V λ caused by the bandwidth of filters is quantitatively evaluated with the aid of a quality indicator, mismatch error f ′ . Results and conclusions in this paper can be used as a guide to optimize the design of the visual sensitivity experiments for V λ measurement. [ABSTRACT FROM AUTHOR]

Since the development of solid-phase peptide synthesis in the 1960s, many laboratories have modified the technology for the production of peptide arrays to facilitate the discovery of novel peptide mimetics and therapeutics. One of these, known as SPOT synthesis, enables parallel peptide synthesis on cellulose paper sheets and has several advantages over other peptide arrays methods. Today, the SPOT technique remains one of the most frequently used methods for synthesis and screening of peptides on arrays. Although polypropylene and glass can be used for the preparation of peptide arrays, the most commonly used material for SPOT membranes is cellulose. Critical to the success of the SPOT synthesis is the ability to modify a cellulose membrane to make it more suitable for solid-phase peptide synthesis of peptides and their analogues. In this review, we highlight the current range of chemical modifications of cellulose that have been developed to enable SPOT synthesis and further enhance its impact on peptide drug discovery. This will contribute to further chemical modifications and applications of SPOT synthesis for peptide arrays and peptide therapeutic screening. SPOT synthesis is one of the popular strategies to prepare peptide arrays. The critical factor for a successful SPOT synthesis is cellulose membrane modification and functionalization. Here, we highlight the current modifications of cellulose to facilitate SPOT synthesis and its contribution to the discovery of novel peptide mimetics and therapeutics. [ABSTRACT FROM AUTHOR]

With the completion of the experimental and regional phases, China's BeiDou Navigation Satellite System (BDS) is being speedily expanded to a global and multifunctional satellite navigation system, BDS III. Confronted with challenges such as limited frequency resources and diversified user requirements, new signals with novel modulation techniques are adopted in BDS III. In addition to the legacy B1I and B3I signals, new open service signals, B1C and B2a/B2b, as well as some new authorized service signals, will be broadcast by BDS III satellites. Among them, B1C and B2a are compatible and interoperable with GPS and Galileo. The modulation techniques and the detailed signal structures of B1C and B2a are introduced in this paper, along with analysis of the initial in‐orbit test results of the new signals. [ABSTRACT FROM AUTHOR]

Abstract In this paper we prove the global in time existence and uniqueness of solutions of the spatially homogeneous Boltzmann equation for Bose–Einstein particles for the hard sphere model for bounded anisotropic initial data. The main idea of our proof is as follows: we first establish an intermediate equation which is closely related to the original equation and is relatively easily proven to have global in time and unique solutions, then we use the multi-step iterations of the collision gain operator to obtain a desired uniform L ∞ -bound for solutions of the intermediate equation so that if an initial datum is sufficiently small relative to the inverse of the Planck constant (which belongs to the case of very high temperature), then the corresponding solution of the intermediate equation becomes the solution of the original equation. [ABSTRACT FROM AUTHOR]

• In this study, an MYB transcription factor CsMYBPA1 which is the upstream regulator of CsGSTU18 was identified by Y1H assay. • Molecular evidence confirmed that CsMYBPA1 activated CsGSTU18 by binding to MBS cis-element on the promoter fragment. • CsMYBPA1, which belong to 5 subfamily of R2R3-MYB, was localized in the nucleus. • Over-expression of CsMYBPA1 could elevate anthocyanin content in transgenic arabidopsis. • The transient silencing of CsMYBPA1 reduced anthocyanin accumulation and decreased the expression of CsGSTU18 in tea leaves, whereas its transient over-expression plants showed the opposite changes. Tea is one of the most widely consumed nonalcoholic beverages worldwide and one of the most important economic crops in the world. Tea varieties rich in anthocyanins have become one of the important breeding targets due to their important health care function. In our previous study, an important gene CsGSTU18 involved in anthocyanin transport was identified. However, the corresponding molecular mechanism is still unclear. Here, we used the promoter sequence of CsGSTU18 as bait in a yeast onehybrid (YIH) screen for promoter-binding proteins. We identified an R2R3-MYB transcription factor, CsMYBPA1, that was coordinately expressed with anthocyanin accumulation. Molecular evidence confirmed that CsMYBPA1 activated CsGSTU18 by binding to MBS cis-element, indicating that CsGSTU18 was a direct target gene of CsMYBPA1. In addition, over-expression of CsMYBPA1 elevated anthocyanin content in transgenic Arabidopsis. Transient silencing of CsMYBPA1 reduced anthocyanin accumulation and decreased the expression level of CsGSTU18 in tea plant leaves, whereas the transient over-expression of CsMYBPA1 showed the opposite change trend. Overall, these findings suggest that CsMYBPA1 directly actives CsGSTU18 to enhance anthocyanin accumulation. This study provides important gene resources and theoretical basis for the anthocyanin metabolism regulation and modification. [ABSTRACT FROM AUTHOR]

Pose estimation plays a crucial role in human-centered vision applications and has advanced significantly in recent years. However, prevailing approaches use extremely complex structural designs for obtaining high scores on the benchmark dataset, hampering edge device applications. In this study, an efficient and lightweight human pose estimation problem is investigated. Enhancements are made to the context enhancement module of the U-shaped structure to improve the multi-scale local modeling capability. With a transformer structure, a lightweight transformer block was designed to enhance the local feature extraction and global modeling ability. Finally, a lightweight pose estimation network— U-shaped Hybrid Vision Transformer, UViT— was developed. The minimal network UViT-T achieved a 3.9% improvement in AP scores on the COCO validation set with fewer model parameters and computational complexity compared with the best-performing V2 version of the MobileNet series. Specifically, with an input size of 384×288, UViT-T achieves an impressive AP score of 70.2 on the COCO test-dev set, with only 1.52 M parameters and 2.32 GFLOPs. The inference speed is approximately twice that of general-purpose networks. This study provides an efficient and lightweight design idea and method for the human pose estimation task and provides theoretical support for its deployment on edge devices. [ABSTRACT FROM AUTHOR]

To combat the serious issue of increasing global antibiotic resistance, new antimicrobial therapies are urgently required. As one alternative, previously used antibiotics are being investigated for use in combination with more modern antibiotics including antimicrobial peptides. Towards this goal, 7-aminocephalosporanic acid, the precursor to the conventional β-lactam antibiotic, cephalosporin, and the related compound, 7-aminodesacetoxycephalosporanic acid, were each chemically modified to enable their use in solid phase peptide synthesis for covalent conjugation via their 7-amino group and a glycolic linker to the N-terminus of a series of cationic antimicrobial peptides, MSI-78, CA(1-7)M(2-9)NH2 and des-Chex1-Arg20. Chemically functionalized Cα-Fm-protected 7-aminocephalosporanic acid and 7-aminodesacetoxycephalosporanic acid building blocks were separately prepared and attached by their 7-amino group to the N-terminus of each peptide on the solid phase via a glutaric anhydride linker. The resulting conjugated AMPs were assessed for antibacterial activity against a panel of six Gram-negative bacteria, including clinically isolated multi-drug resistant (MDR) pathogens. Only the conjugated MSI-78 analogues displayed significant activity against Acinetobacter baumannii and MDR A. baumannii 156 and enhanced activity against Klebsiella pneumoniae. Further work is required to optimize the conjugation of AMPs to 7-cephalosporanic acid and/or 7-aminodesacetoxycephalosporanic acid to universally induce an enhanced effect on killing of drug sensitive and MDR bacterial strains that are common causes of hospital-acquired infections. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to conduct a meta-analysis of retrospective studies that investigated the association of preoperative C-reactive protein (CRP) levels with the overall survival (OS) of patients with bone neoplasms. Methods: A detailed literature search was performed in the Cochrane Library, Web of Science, Embase and PubMed databases up to August 28, 2017, for related research publications written in English. We extracted the data from these studies and combined the hazard ratios (HR) and 95% confidence intervals (CIs) to assess the correlation between CRP levels and OS in patients with bone neoplasms. Results: Five studies with a total of 816 participants from several countries were enrolled in this current meta-analysis. In a pooled analysis of all the publications, increased serum CRP levels had an adverse prognostic effect on the overall survival of patients with bone neoplasms. However, the combined data showed no significant relationship between the level of CRP and OS in Asian patients (HR = 1.73; 95% CI: 0.86–3.49; P = 0.125). Similar trends were observed in patients with bone neoplasms when stratified by ethnicity, histology, metastasis and study sample size. Conclusions: The results of this meta-analysis suggest that increased CRP expression indicates a poorer prognosis in patients with bone neoplasms. More prospective studies are needed to confirm the prognostic significance of CRP levels in patients with bone neoplasms. [ABSTRACT FROM AUTHOR]

Protein-protein interactions, living cells, fluorescence, proximity labeling, enzyme, photoactivation Keywords: protein-protein interactions; living cells; fluorescence; proximity labeling; enzyme; photoactivation EN protein-protein interactions living cells fluorescence proximity labeling enzyme photoactivation 1 1 1 07/19/23 20230717 NES 230717 B Elucidation of Protein-Protein Interactions (PPIs) b in living cells/animals is very important for the study of basic biology and the development of novel therapeutics. Front Cover: Chemical and Biological Strategies for Profiling Protein-Protein Interactions in Living Cells (Chem. [Extracted from the article]

Two series of branched tetramers of the proline-rich antimicrobial peptide (PrAMP), Chex1-Arg20, were prepared to improve antibacterial selectivity and potency against a panel of Gram-negative nosocomial pathogens including Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa. First, tetramerization was achieved by dithiomaleimide (DTM) conjugation of two C-terminal-cysteine bearing dimers that also incorporated C-terminal peptide chemical modification. DTM-linked tetrameric peptides containing a C-terminal hydrazide moiety on each dimer exhibited highly potent activities in the minimum inhibitory concentration (MIC) range of 0.49-2.33 μ m. A second series of tetrameric analogues with C-terminal hydrazide modification was prepared by using alternative conjugation linkers including trans-1,4-dibromo-2-butene, α,α'-dibromo- p-xylene, or 6-bismaleimidohexane to determine the effect of length on activity. Each displayed potent and broadened activity against Gram-negative nosocomial pathogens, particularly the butene-linked tetrameric hydrazide. Remarkably, the greatest MIC activity is against P. aeruginosa (0.77 μ m/8 μg mL−1) where the monomer is inactive. None of these peptides showed any cytotoxicity to mammalian cells up to 25 times the MIC. A diffusion NMR study of the tetrameric hydrazides showed that the more active antibacterial analogues were those with a more compact structure having smaller hydrodynamic radii. The results show that C-terminal PrAMP hydrazidation together with its rational tetramerization is an effective means for increasing both diversity and potency of PrAMP action. [ABSTRACT FROM AUTHOR]

• In this study, RNA-seq analysis of the green and purple leaves was performed to screen the important genes relate to anthocyanin accumulation regulation in tea plants. • CsGSTU18, belong to Tau subfamily of glutathione S-transferase, is positive correlation with anthocyanin contents. • CsGSTU18 which exhibited the highest expression in the second leaf was localized in the endoplasmic reticulum and cytoplasm. • Over-expression of CsGSTU18 enhanced anthocyanin accumulation in transgenic Arabidopsis and rescued the anthocyanin-deficient phenotype of strawberry rap mutant. • AsODN-mediated transient silencing of CsGSTU18 significantly reduced anthocyanin accumulation in tea plant leaves, whereas the transient over-expression of CsGSTU18 showed the opposite change trend. Tea plant (Camellia sinensis) is a natural health drink. Because of its unique taste and the health-care effects of natural products, tea is more and more popular and concerned with people. Under the conditions of high temperature and strong light, the young leaves of tea plants are prone to accumulate anthocyanins, which in turn affects the suitability and quality of tea leaves. Here, we screened a key significantly up-regulated glutathione S-transferase 18 (CsGSTU18) gene from both cultivars 'Zi 1' (Z1) and 'Shaanxi Ziyang' (SZ) by RNA-seq. CsGSTU18, which belongs to Tau subfamily, was localized in the endoplasmic reticulum and cytoplasm. The overexpression of CsGSTU18 enhanced anthocyanin accumulation in transgenic Arabidopsis and rescued the anthocyanin-deficient phenotype of strawberry reduced anthocyanins in petioles (rap) mutant. Antisense oligonucleotide (asODN)-mediated transient silencing of CsGSTU18 significantly reduced anthocyanin accumulation in tea plant leaves, whereas the transient overexpression of CsGSTU18 showed the opposite change trend. Overall, these findings suggest that CsGSTU18 plays an important role in anthocyanin accumulation, which result in the tea tender shoot turning purple. This study provides a basis for further research on the molecular mechanism of anthocyanin accumulation in tea plant. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fluidized electrocatalysis system using V 2 O 5 nanodots electrocatalyst was reported. • V 2 O 5 nanodots electrocatalyst exhibits superior bifunctional NRR and NOR activities. • DFT calculations affirm the role of oxygen vacancies in N 2 adsorption and activation. • Monte Carlo simulation discerns the mechanistic insights of such fluidized system. We report a fluidized electrocatalysis system using V 2 O 5 nanodots (V 2 O 5 NDs) electrocatalyst dispersed in aqueous electrolyte for efficiently ambient electrocatalytic nitrogen reduction reaction (NRR) and nitrogen oxidation reaction (NOR). Compared to the conventional catalyst-immobilized approach, the V 2 O 5 NDs catalyst with such fluidized approach exhibits superior bifunctional activities toward NRR and NOR, affording a high NH 3 yield of 575.3 μg h−1 mg−1 and a faradaic efficiency (FE) of 28.7 % for NRR and a high NO 3 – yield of 1388.0 μg h−1 mg−1 and a FE of 12.6 % for NOR, respectively. The high bifunctional activities of V 2 O 5 NDs are originated from the abundant oxygen vacancies as the active sites for the adsorption and activation of N 2 , affirmed by the DFT calculations. Furthermore, a theoretical model is built by the Monte Carlo simulation to confirm the important role of nanodots-incorporated fluidized approach in enhancement of mass transport and regeneration of active sites. [ABSTRACT FROM AUTHOR]

With water as the reaction medium, an efficient protocol has been developed for the synthesis of Z-β-sulfonyl-α,β-unsaturated carbonyl products via water-promoted sulfonylation of alkynylcarbonyl compounds with sodium sulfinates. This strategy could effectively avoid the use of toxic organic solvents, catalysts and additives. This method features a wide substrate scope with a broad range of functional group tolerance, utilizes easily available starting materials, can be scaled-up, and is operationally simple. [ABSTRACT FROM AUTHOR]

The increasing prevalence of antibiotic-resistant pathogens requires the development of new antibiotics. Proline-rich antimicrobial peptides (PrAMPs), including native apidaecins, Bac7, and oncocins or designed A3APO, show multi-modal actions against pathogens together with immunostimulatory activities. The interactions of the designed PrAMP, Chex1-Arg20, and its dimeric and tetrameric oligomers with different model membranes were investigated by circular dichroism spectroscopy, dynamic light scattering, zeta potential, differential scanning calorimetry, and dye leakage. Chex1-Arg20 oligomers showed stronger affinity and preferential binding to negatively charged phospholipid bilayers and led to lipid aggregation and neutralization. Fluorescence microscopy of negatively charged giant unilamellar vesicles with AlexFluor-647-labeled Chex1-Arg20 dimers and tetramers displayed aggregation at a peptide/lipid low ratio of 1:200 and at higher peptide concentrations (1:100/1:50) for Chex1-Arg20 monomer. Such interactions, aggregation, and neutralization of PrAMP oligomers additionally showed the importance of interactions of PrAMPs with negatively charged membranes. [ABSTRACT FROM AUTHOR]

Background: Apolipoprotein E (APOE) is the most recognized risk gene for cognitive decline and clinical progression of late-onset Alzheimer's disease (AD); nonetheless, its association with neuropsychiatric symptoms (NPSs) remains inconclusive. Objective: To investigate the association of APOE ɛ4 with NPSs and explore nutritional status and cognition as joint mediators of this association. Methods: Between June 2021 and October 2022, patients with amnestic mild cognitive impairment (aMCI) or AD were recruited from the Chinese Imaging, Biomarkers, and Lifestyle Study. NPSs were assessed using the Neuropsychiatric Inventory, while global cognition and nutritional status were evaluated using the Mini-Mental State Examination (MMSE) and Mini-Nutritional Assessment (MNA), respectively. Simple mediation and multiple chain mediation models were developed to examine the mediating effects of the MNA and MMSE scores on the relationship between APOE ɛ4 and specific neuropsychiatric symptom. Results: Among 310 patients, 229 (73.87%) had NPSs, and 110 (35.48%) carried APOE ɛ4. Patients with APOE ɛ4 were more likely to have hallucinations (p = 0.014), apathy (p = 0.008), and aberrant motor activity (p = 0.018). MNA and MMSE scores mediated the association between APOE ɛ4 and hallucinations (17.97% and 37.13%, respectively), APOE ɛ4 and apathy (30.73% and 57.72%, respectively), and APOE ɛ4 and aberrant motor activity (17.82% and 34.24%), respectively. Chain-mediating effects of MNA and MMSE scores on the association of APOE ɛ4 with hallucinations, apathy, and aberrant motor activity after adjusting for confounding factors were 6.84%, 11.54%, and 6.19%, respectively. Conclusion: Nutritional status and cognition jointly mediate the association between APOE ɛ4 and neuropsychiatric symptoms in patients with aMCI or AD. [ABSTRACT FROM AUTHOR]

• IL-6-/- mice are less susceptible to develop tumors, compared to WT mice. • Infiltrated CD8+ T cells are found to exhibit high expression in tumor of IL-6-/- mice. • IL-6 acts as a negative regulator in IFNγ-STAT1-MHC-I signaling. • Blockade of IL-6 also increased CD8+ T cells in the CT26 subcutaneous tumors and sensitize animals to anti-PD-1 therapy. Long-standing inflammatory bowel disease predisposes to the development of colorectal cancer (CRC). Interleukin (IL) -6, a pivotal link between chronic inflammation and tumor progression, has recently been recognized as a potential therapeutic target. The effect of IL-6 on proliferation and metastasis of CRC by activating the STAT3 pathway has been widely demonstrated in recent years, but few on mediating tumor immune evasion. In this study, we found that IL-6 was remarkably overexpressed in CRC and its elevation was associated with a poor prognosis. We studied CRC tumorigenesis in vivo by inoculating MC38 tumors and induced-CRC model via AOM/DSS (azoxymethane/dextran sulfate sodium) in IL-6 deficient (IL-6-/-) and wild-type (WT) mice and found that IL-6-/- mice were less susceptible to develop tumors, compared to WT mice. We detected CD8+ T cells via immunofluorescence and found they exhibit high expression in tumor of IL-6-/- mice. High level of IL-6 was found in colitis model, with down-regulation of MHC-I molecules. In in vitro experiments, we found that IL-6 may act as a negative regulator in IFNγ-STAT1-MHC-I signaling. In addition, vivo trials also confirmed that MHC-I mRNA level was negatively related to the existence of IL-6. Furthermore, the blockade of IL-6 also activated CD8+ T -cell accumulation and led to the high PD-L1 expression in CRC, which can sensitize animals to anti-PD-1 therapy. Our study provides a research basis for the significant role of IL-6 in tumor evasion and highlights a novel target to improve the efficacy of immunotherapy. [ABSTRACT FROM AUTHOR]

Summary A3-APO, a de novo designed branched dimeric proline-rich antimicrobial peptide (PrAMP), is highly effective against a variety of in vivo bacterial infections. We undertook a selective examination of the mechanism for the Gram-negative Escherichia coli bacterial membrane interaction of the monomer (Chex-Arg20), dimer (A3-APO), and tetramer (A3-APO disulfide-linked dimer). All three synthetic peptides were effective at killing E. coli . However, the tetramer was 30-fold more membrane disruptive than the dimer while the monomer showed no membrane activity. Using flow cytometry and high-resolution fluorescent microscopy, it was observed that dimerization and tetramerization of the Chex-Arg20 monomer led to an alteration in the mechanism of action from non-lytic/membrane hyperpolarization to membrane disruption/depolarization. Our findings show that the membrane interaction and permeability of Chex-Arg20 was altered by multimerization. [ABSTRACT FROM AUTHOR]