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Metabolites of microorganisms have long been considered as potential sources for drug discovery. In this study, five new depsidone derivatives, talaronins A-E (1–5) and three new xanthone derivatives, talaronins F–H (6–8), together with 16 known compounds (9–24), were isolated from the ethyl acetate extract of the mangrove-derived fungus Talaromyces species WHUF0362. The structures were elucidated by analysis of spectroscopic data and chemical methods including alkaline hydrolysis and Mosher’s method. Compounds 1 and 2 each attached a dimethyl acetal group at the aromatic ring. A putative biogenetic relationship of the isolated metabolites was presented and suggested that the depsidones and the xanthones probably had the same biosynthetic precursors such as chrysophanol or rheochrysidin. The antimicrobial activity assay indicated that compounds 5, 9, 10, and 14 showed potent activity against Helicobacter pylori with minimum inhibitory concentration (MIC) values in the range of 2.42–36.04 μmol/L. While secalonic acid D (19) demonstrated significant antimicrobial activity against four strains of H. pylori with MIC values in the range of 0.20 to 1.57 μmol/L. Furthermore, secalonic acid D (19) exhibited cytotoxicity against cancer cell lines Bel-7402 and HCT-116 with IC50 values of 0.15 and 0.19 μmol/L, respectively. The structure–activity relationship of depsidone derivatives revealed that the presence of the lactone ring and the hydroxyl at C-10 was crucial to the antimicrobial activity against H. pylori. The depsidone derivatives are promising leads to inhibit H. pylori and provide an avenue for further development of novel antibiotics.

A contribution to the engineering application of a proposed 500 kV fault current limiter (FCL) is presented. A new type of FCL composed of a highly coupled split reactor (HCSR) and fast switches is proposed. When the circuit breaker (CB) in series with the FCL in the 500 kV power system interrupts the limited fault current, the rate of rise of the recovery voltage (RRRV) reaches a value much higher than the rated value. Based on a simplified equivalent single‐phase circuit, the influence of the new FCL on the interruption procedure of the CB is simulated and discussed. The simulation results show that the high RRRV is caused by high‐frequency resonant oscillations between the HCSR and its parasite capacitance. Analysis indicates that when the reactance of the FCL is close to the short circuit reactance of the system, the RRRV will reach the highest value. To solve this issue, we proposed installing a shunt capacitor with the FCL. Simulation results showed that the RRRV under all fault modes could be restrained to below the rated value by introducing a certain shunt capacitor.

Two new austocystin analogs, austocystin P (1) and austocystin Q (2), along with fourteen known compounds (3-16) were isolated from the fermentation extract of Aspergillus sp. WHUF05236. The planar structures of 1 and 2 were elucidated through 1D, 2D NMR and MS analyses. Their absolute configurations were determined by the time-dependent density functional (TDDFT)-ECD calculation. Compounds 3, 11, and 12 exhibited antimicrobial activities against Helicobacter pylori with MIC values ranging from 20.00 to 43.47 μM. Compounds 3, 6, and 7 showed cytotoxicities against the human colon cancer cell lines Hct-116 with IC

The spatial distribution of multiple species in a vacuum arc is an essential microscopic feature. Ionization, recombination, and species diffusion are the main factors affecting the distribution of arc particles. The purpose of this paper is to investigate the spatial distribution characteristics of multiple species in a vacuum arc using a high-speed camera and interference filters. CuCr50 and pure copper plate electrodes were used to conduct arc-burning experiments in a demountable vacuum chamber. The distribution of different species was obtained by arranging interference filters outside the quartz glass window. The experimental results show that most neutral atoms originated from the evaporation of the electrode material and were distributed on the electrode surface. Strong ionization of ions and atoms near the cathode caused the number of single-charged ions to increase, and their ion density gradually decreased along the axial direction with increasing distance from the cathode. Double-charged ions were mainly distributed near the anode where the electron temperature was higher, and their density increased along the axial direction with increasing distance to the cathode. The above conclusions provide a basis for further research on the characteristics of microscopic particles in vacuum arcs.

In fractured tight reservoirs, the seepage capacity of the matrix is poor, and fluid migration mainly depends on matrix/fracture transfer. An accurate understanding of the matrix/fracture flow is the basis of well tests and numerical simulations for tight reservoirs. In this paper, the unsteady flow equation for tight reservoirs is deduced based on the boundary layer theory, which can reflect the effect of the dynamic threshold pressure gradient, and the theoretical flow equation is verified by seepage experiments. Based on the study of the flow equation, the approximate semi‐analytical solution of the matrix/fracture unsteady transfer shape factor and the transfer function for tight reservoirs are established considering the early stage of matrix/fracture transfer (pressure does not propagate to the matrix center) and the late stage of matrix/fracture transfer (pseudo‐steady state). The results show that the shape factor of the tight reservoir is mainly affected by three factors (minimum threshold pressure gradient, static boundary layer thickness, and sensitivity coefficient of the fluid boundary layer), and the theoretical curves show that the intermediate transfer enters the pseudo‐steady state when the dimensionless time reaches approximately 0.14. The higher the minimum threshold pressure gradient is, the larger the transfer shape factor. The larger the static boundary layer thickness is, the larger the transfer shape factor; additionally, the larger the sensitivity coefficient of the fluid boundary layer is, the faster the change rate of the shape factor. Finally, the transfer shape factor is applied to a well test interpretation. Examples prove that the fitting accuracy of the new curve type is improved by 34.2% compared with the curve type for the conventional well test interpretation method.

Great progress has been achieved in the development of fault current limiters (FCL) in recent years. However, there has been no domestic or overseas standard basis directly in terms of experimental verification. Short circuit testing of high-voltage FCL requires tremendous system capacities. Hence equivalent synthetic methods of testing should be considered. Due to the particularity of component parts in FCL, synthetic testing methods for circuit breakers may induce insulation stress in abnormal conditions. Based on the working principles of high-voltage FCL with high coupling split reactors, equivalent testing methods should be considered firstly, the paper conducts research and analysis on relevant domestic and overseas standards as well as lab capacities, and puts forward equivalent methods of short circuit testing. Then, testtag plans are formulated with actual working status. Lastly, system simulations on the feasibility of plans are carried out.

The vacuum circuit breakers(VCBs) are commonly used in the medium and lower voltage power systems. With the requirements of current limiters, the interruption characteristics of the vacuum circuit breaker need to be improved. As to obtain the relationships between interruption characteristics and arcing extinguishing chamber key structures, tests are adopted to a 40.5kV vacuum circuit breaker in this paper, and lots of calculations are carried out for optimization of electromagnetic field. It is shown that for the application in current limiters, contact structures and coil must be designed and optimized for obtaining larger magnetic force so as to interrupt the arc under the conditions of higher DC component and shorter arcing time. Testing results reveals that the interruption behaviors are affected by the polarity of the vacuum circuit breaker, it is harder for interrupting when polarity is positive, and the interruption performance of the VCB is decreasing because of the electrical inductance existing in the current limiter.

Vacuum circuit breakers are widely used in medium and low voltage power system. This article is based on the national key R&D project "Development of economical high-voltage AC current limiter for voltage levels of 500kV and above", which mainly studies a 40.5kV/50kA vacuum interrupter(VI). The special VI was used for the current limiter to interrupt the arc under the conditions of higher DC component and shorter arcing time. In order to obtain the structures of the contacts and the repulsion mechanism, lots of magnetic simulating calculations were carried out. A 2/3 coil-type contact structure was used in this paper. Then, a 40.5kV/50kA VI with the 2/3 coil-type contact structure was designed by electric field simulating calculations. A fast repulsion mechanism was used as the driving component to carry out the rated symmetric short-circuit current breaking test (T100s) and the rated asymmetric short-circuit current breaking test (T100a) under the parameters described in the paper. At present, the VI designed in this paper could successfully break the rated short circuit current of 50kA, and the DC component of T100a was 78%.

Trained immunity, induced by β-glucan in monocytes, is mediated by activating metabolic pathways that result in epigenetic rewiring of cellular functional programs; however, molecular mechanisms underlying these changes remain unclear. Here, we report a key immunometabolic and epigenetic pathway mediated by the miR–9-5p-isocitrate dehydrogenase 3α (IDH3α) axis in trained immunity. We found that β-glucan–trained miR–9-5p–/– monocytes showed decreased IL-1β, IL-6, and TNF-α production after LPS stimulation. Trained miR–9-5p–/– mice produced decreased levels of proinflammatory cytokines upon rechallenge in vivo and had worse protection against Candida albicans infection. miR–9-5p targeted IDH3α and reduced α-ketoglutarate (α-KG) levels to stabilize HIF-1α, which promoted glycolysis. Accumulating succinate and fumarate via miR–9-5p action integrated immunometabolic circuits to induce histone modifications by inhibiting KDM5 demethylases. β-Glucan–trained monocytes exhibited low IDH3α levels, and IDH3α overexpression blocked the induction of trained immunity by monocytes. Monocytes with IDH3α variants from autosomal recessive retinitis pigmentosa patients showed a trained immunity phenotype at immunometabolic and epigenetic levels. These findings suggest that miR–9-5p and IDH3α act as critical metabolic and epigenetic switches in trained immunity.

Ischemic stroke has been reported to cause significant changes to memory, thinking, and behavior. Intriguingly, recently reported studies have indicated the association of Trimethylamine N-oxide (TMAO) with the acute phase of ischemic stroke. However, the comprehensive underlying mechanism remained unknown. The objective of the present study was to investigate the association between TMAO and recovery of neurological function after ischemic stroke. For this purpose, a middle cerebral artery occlusion/reperfusion (MCAO/R) rat model was established and treated with TMAO or/and sh-ALK5, followed by the neurological function evaluation. Behaviors of rats were observed through staircase and cylinder tests. Moreover, the expression of Smurf2 and ALK5 was detected by immunohistochemistry while expression of GFAP, Neurocan, and Phosphacan in brain tissues was determined by immunofluorescence. Thereafter, gain- and loss-of-function assays in astrocytes, the proliferation, viability, and migration were evaluated by the EdU, CCK-8, and Transwell assays. Besides, Smurf2 mRNA expression was determined by the RT-qPCR, whereas, Smurf2, ALK5, GFAP, Neurocan, and Phosphacan expression was evaluated by the Western blotting. Finally, the interaction of Smurf2 with ALK5 and ALK5 ubiquitination was assessed by the co-immunoprecipitation. Notably, our results showed that TMAO promoted the proliferation of reactive astrocyte and formation of glial scar in MCAO/R rats. However, this effect was abolished by the Smurf2 overexpression or ALK5 silencing. We further found that TMAO upregulated the ALK5 expression by inhibiting the ubiquitination role of Smurf2. Overexpression of ALK5 reversed the inhibitory effect of Smurf2 on astrocyte proliferation, migration, and viability. Collectively, our work identifies the evolutionarily TMAO/Smurf2/ALK5 signaling as a major genetic factor in the control of reactive astrocyte proliferation and glial scar formation in ischemic stroke, thus laying a theoretical foundation for the identification of ischemic stroke.

Acute myeloid leukemia (AML) is a fatal disease characterized by the accumulation of immature myeloid blasts in the bone marrow (BM). Cytokine provide signals for leukemia cells to improve their survival in the BM microenvironment. Previously, we identified interleukin-33 (IL-33) as a promoter of cell survival in a human AML cell line and primary mouse leukemia cells. In this study, we report that the cell surface expression of IL-33–specific receptor, Interleukin 1 Receptor Like 1 (IL1RL1), is elevated in BM cells from AML patients at diagnosis, and the serum level of IL-33 in AML patients is higher than that of healthy donor controls. Moreover, IL-33 levels are found to be positively associated with IL-6 levels in pediatric patients with AML. In vitro, IL-33 treatment increased IL-6 mRNA expression and protein level in BM and peripheral blood (PB) cells from AML patients. Evidence was also provided that IL-33 inhibits cell apoptosis by activating p38 mitogen-activated protein kinase (MAPK) pathway using human AML cell line and AML patient samples. Finally, we confirmed that IL-33 activated IL-6 expression in a manner that required p38 MAPK pathway using clinical AML samples. Taken together, we identified a potential mechanism of IL-33–mediated survival involving p38 MAPK in pediatric AML patients that would facilitate future drug development.

The phenomenon of 500 kV line short-circuit urrent exceeding the protection scope of circuit breaker is seriously threatening the safety of power grid, and installing a suitable fault current limiter is an effective method to deal with such problem. 550 kV high coupled split reactor studied in this paper is an important component of 500kV fault current limiter that is desighed with new technology. It has the functions of withstanding and limiting short-circuit current, and has the advantages of high flexibility, easy maintenance and low loss. However, at present, there is a lack of relevant literature and standards to guide this type of equipment for the evaluation of mechanical and thermal stress under actual conditions. This paper studied the actual working conditions of 550kV high coupled split reactor, analyzed its current characteristics, and on this basis, performed steady-state temperature field simulation analysis at rated continuous current and stress calculation during short circuit, and proposed a scheme for equivalent test using a small prototype in the actual conditions of the laboratory. This paper is beneficial to the design and testing of such equipment in the future.

Breath volatile biomarkers are capable of distinguishing patients with various cancers. However, high throughput analytical technology is a prerequisite to a large-cohort study intended to discover reliable breath biomarkers for cancer diagnosis. Single-photon ionization (SPI) is a universal ionization technology, and SPI-mass spectrometry (SPI-MS) shows a remarkable advantage in the comprehensive detection of volatile organic compounds (VOCs), in particular, nonpolar compounds. In this study, we have introduced SPI-MS coupled with on-line thermal desorption (TD-SPI-MS) to demonstrate nontarget analysis of breath VOCs for gastric cancer patients. The breath fingerprints of the gastric cancer patients were significantly distinct from that of the control group. Acetone, isoprene, 1,3-dioxolan-2-one, phenol, meta-xylene, 1,2,3-trimethylbenzene, and phenyl acetate showed higher relative peak intensities in the breath profiles of gastric cancer patients. A diagnostic prediction model was further developed by using a training set (121 samples) and validated with a test set (53 samples). The predication accuracy of the developed model was 96.2%, and the area under the curve (AUC) of the receiver operator characteristic curve (ROC) was 0.997, indicating a satisfactory prediction ability of the developed model. Thus, by taking gastric cancer as an example, we have shown that TD-SPI-MS will be a promising tool for high throughput analysis of breath samples to discover characteristic VOCs in patients with various cancers.

Fashion products typically feature in compositions of a variety of styles at different clothing parts. In order to distinguish images of different fashion products, we need to extract both appearance (i.e., "how to describe") and localization (i.e.,"where to look") information, and their interactions. To this end, we propose a biologically inspired framework for image-based fashion product retrieval, which mimics the hypothesized twostream visual processing system of human brain. The proposed attentional heterogeneous bilinear network (AHBN) consists of two branches: a deep CNN branch to extract fine-grained appearance attributes and a fully convolutional branch to extract landmark localization information. A joint channel-wise attention mechanism is further applied to the extracted heterogeneous features to focus on important channels, followed by a compact bilinear pooling layer to model the interaction of the two streams. Our proposed framework achieves satisfactory performance on three image-based fashion product retrieval benchmarks., Comment: 11 pages, 8 figures

It is of great significance to achieve good cooperation between the fast vacuum switch driven by the electromagnetic repulsion mechanism and the buffer system. The purpose of this paper is to study the cooperation of the 40.5kV fast vacuum switch driven by the electromagnetic repulsive mechanism and the oil damper. Firstly, the dynamic characteristics of the electromagnetic repulsion mechanism during the opening process were simulated by MAXWELL software. Then, based on the dynamic characteristics of the electromagnetic repulsive mechanism, a simplified model of the oil buffer is established by AMESim software and its cushioning characteristics are simulated. Moreover, the influence of the buffer piston area and the annular gap width on the cushioning characteristics of oil buffer is analyzed. Finally, the dynamic characteristics of the electromagnetic repulsion mechanism under the action of the oil damper are simulated and analyzed. It provides some guidance for the cooperation of the fast vacuum switch driven by the electromagnetic repulsive mechanism and the oil damper.

As an instance-level recognition task, person re-identification methods always calculate local features by horizontal pooling. It is based on a simple assumption that pedestrians always stand vertically. But as to wildlife re-identification task, we can not make similar assumption since the various view-angles of wildlife. In this paper, we propose a novel dynamic partial matching method. In our module, global feature learning benefits greatly from local feature learning, which performs an alignment/matching by flipping local features and calculating the shortest path between them. Besides the partial matching method, we also consider a series of data augmentation methods such as flip as new id, random whitening, random crop and so on. And we also use an example sampling strategy, i.e., hard negative mining, for training. In addition, we ensemble the models with different backbones and epochs using imagenet pre-trained models. Extensive experiments validate the superiority of our method for tiger Re-ID. Code has been released at https://github.com/vvictoryuki/tiger_reid_pytorch.

Circuit breakers are important control and protection devices in power systems and are essential for ensuring safe and reliable operation of power systems. In recent years, the application of fast electromagnetic repulsive mechanism based on the principle of eddy current in vacuum circuit breaker has gradually become a hot research topic. However, due to the large mass of the moving mechanism and the large opening distance in the high voltage vacuum circuit breaker, it is difficult for the ordinary mechanism to break quickly. Therefore, a double-layer coil type fast electromagnetic repulsive mechanism is proposed, which can generate a larger electromagnetic repulsive force to achieve fast driving of the mechanism. Taking the 40.5kV/50kA vacuum circuit breaker as an example, the 2D finite element model was built by MAXWELL software, and its motion characteristics were simulated. In addition, the effect of the metal plate thickness, coil inner radius, number of coil turns and initial gap on the motion characteristics of the fast electromagnetic repulsive mechanism is investigated. The results show that the rise time of the electromagnetic repilsive force is very short. In contrast, the electromagnetic repilsive force has a long time to fall, and the peak value of the electromagnetic repilsive force is large. Thickening the metal plate, increasing the inner radius of the coil plate, increasing the number of coil turns and reducing the initial gap can increase the speed of the rapid electromagnetic repulsive mechanism. The simulation analysis provides a basis for further design of the electromagnetic repilsive mechanism.

Targeting of Mycobacterium tuberculosis (MTB) PE/PPE antigens that induce type 1 helper T cell (Th1) and Th17 responses represents a crucial strategy for the development of tuberculosis (TB) vaccines. However, only a few PE/PPE antigens induce these responses. Here, we sought to determine how the cell wall–associated antigen PPE60 (Rv3478) activates dendritic cell (DC) maturation and T-cell differentiation. We observed that PPE60 induces DC maturation by augmenting the protein expression of cluster of differentiation 80 (CD80) and CD86 and major histocompatibility complex (MHC) class I and MHC class II on the cell surface. PPE60 also stimulated the production of tumor necrosis factor-α (TNFα), interleukin (IL)-1β, IL-6, IL-12p70, and IL-23p19 but not IL-10. This induction was mediated by Toll-like receptor 2 (TLR2) and followed by activation of p38, c-Jun N-terminal kinase (JNK), and NF-κB signaling. PPE60 enhanced MHC-II expression and promoted antigen processing by DCs in a TLR2-dependent manner. Moreover, PPE60-stimulated DCs directed naïve CD4(+) T cells to produce IFN-γ, IL-2, and IL-17A, expanding the Th1 and Th17 responses, along with activation of T-bet and RAR-related orphan receptor C (RORγt) but not GATA-3. Moreover, PPE60 activated the NLRP3 inflammasome followed by caspase-1–dependent IL-1β and IL-18 synthesis in DCs. Of note, pharmacological inhibition of NLRP3 activation specifically attenuated IFN-γ and IL-17A secretion into the supernatant from CD4(+) T cells cocultured with PPE60-activated DCs. These findings indicate that PPE60 induces Th1 and Th17 immune responses by activating DCs in a TLR2-dependent manner, suggesting PPE60's potential for use in MTB vaccine development.

Two new xanthone derivatives, spinosusones A (1) and B (2), and a new tryptoquivaline analogue, asperdiazapinone G (3), together with nine known compounds (4-12) were isolated from the EtOAc extract of the marine-derived fungus Aspergillus sp . WHUF03110. The structures of 1-3 were determined by spectroscopic analysis, and comparison with literature data. Most of these isolated compounds were evaluated for their antimicrobial activities against ten Gram-negative and seven Gram-positive bacteria, Mycobacterium smegmatis ATCC 607, Candida albicans ATCC SC5314, and C. albicans YY-1-4. Compound 10 displayed strong antibacterial activity against five Gram-positive bacteria ( Bacillus subtilis 168, Staphylococcus aureus ATCC25923, S. aureus NEWMAN, S. aureus USA300, S. aureus NRS 271) with MIC values ranging from 1.0 to 2.0 μg/mL, and displayed moderate antibacterial activity against four Gram-negative bacteria ( Helicobacter pylori 26695, H. pylori G27, H. pylori 159, H. pylori 129) and M. smegmatis ATCC 607 with a MIC value of 8.0 μg/mL.