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Tumor immune microenvironment exerts a profound effect on the population of infiltrating immune cells. Tissue inhibitor of matrix metalloproteinase 1 (TIMP1) is frequently overexpressed in a variety of cells, particularly during inflammation and tissue injury. However, its function in cancer and immunity remains enigmatic. In this study, we find that TIMP1 is substantially up-regulated during tumorigenesis through analyzing cancer bioinformatics databases, which is further confirmed by IHC tissue microarrays of clinical samples. The TIMP1 level is significantly increased in lymphocytes infiltrating the tumors and correlated with cancer progression, particularly in GBM. Notably, we find that the transcriptional factor Sp1 binds to the promoter of TIMP1 and triggers its expression in GBM. Together, our findings suggest that the Sp1-TIMP1 axis can be a potent biomarker for evaluating immune cell infiltration at the tumor sites and therefore, the malignant progression of GBM. [ABSTRACT FROM AUTHOR]

Effective identification of sulfur ions (S2−) in foodstuff is crucial for food safety and human health, but it remains challenging. Traditional single-mode colorimetric sensing methods are simple and sensitive, but are prone to interference from colored substances which can lead to false positives or negatives results. Herein, we develop a novel "mix-response" biosensor for colorimetric and photothermal dual-mode detection of S2− with good simplicity, sensitivity and portability. In this biosensor, silver-doping Prussian blue nanoparticle (SPB NPs) was used as signal output component, which not only exhibits blue color characteristics, but also has photothermal conversion properties activated by near-infrared (NIR) laser. Upon increasing the S2− concentration, the prepared SPB NPs undergo etching, leading to the formation of new silver sulfide precipitation (Ag 2 S), along with different colorimetric and photothermal response signals. For the portable visualization of S2−, the color information was recorded by a smartphone in combination with RGB (red channel) analysis and the evolution of the photothermal signal was documented by a thermal imager. The introduction of smartphone and handheld thermal imager in this "mix-response" biosensor makes it suitable for on-site quantitative detection of S2− without sophisticated instrument. Moreover, the development of this "mix-response" biosensor does not need the use of recognition probes (e.g. aptamers and reaction intermediates), thereby simplifying the construct procedures of sensing strategies and improving the economic efficiency of detection. More importantly, the photothermal response signals can overcome the interference of colored substances in foods, thereby reducing the false positives or negatives of the detection results. [Display omitted] • A novel "mix-response" biosensor for dual-mode detection of S2− is developed. • This biosensor simplifies the construct procedures without the use of identification probes. • The photothermal signal can overcome the interference of colored substances. • Introduction of smartphone and thermal imager make it suitable for on-site quantitative detection of S2−. [ABSTRACT FROM AUTHOR]

• Dynamic contact behaviors between steel wires and saddle materials (transverse slip, longitudinal deformation, contact state) were presented. • Effects of transverse and longitudinal locations, friction cycles and saddle material on dynamic contact behaviors were explored. In order to prevent skid accidents of main cable of suspension bridge, dynamic contact behaviors between saddle materials and steel wires were explored in the present study. Dynamic contact tests of saddle materials were conducted employing the self-made dynamic contact test rig. Dynamic contact behaviors of the saddle material (transverse slip, longitudinal deformation, contact state, wear mechanism) in a friction cycle were investigated. Effects of transverse and longitudinal locations, friction cycles and saddle materials on the dynamic contact behaviors were presented. The results show that dynamic contact states between saddle specimen and steel wireexhibits the adhesion-gross slip-adhesion-gross slip state in a friction cycle. The transverse slip and longitudinal deformation of saddle specimen both decrease with increasing distance to the contact interface, decrease along the transverse sliding direction, and increase with increasing friction cycles. The ZG270-480 saddle material exhibits the largest average transverse slip and longitudinal deformation, while ZG275-485 saddle material shows the smaller values. [ABSTRACT FROM AUTHOR]

Abstract: Quartz crystal microbalance dissipation (QCM-D) was used to monitor the layer by layer (LBL) self-assemble process of decyl bis phosphonate (DBP) and Collagen on titanium. The mass and viscoelastic properties of self-assembled layers were obtained using QCM-D. The stability of DBP and Collagen layer on titanium was tested to be very good. Osteoblasts cell culture was performed on LBL modified samples and that after BSA adsorption. The morphology of cells was observed by a scanning electron microscope (SEM). The total metabolic activity and differentiation of osteoblasts were evaluated by a metabolic assay and alkaline phosphatase (ALP) activity, respectively. These tests showed that osteoblasts have better activity, proliferation, and differentiation on Collagen terminated samples and BSA adsorbed samples. These results, along with the good biomineralization and protein adsorption abilities of Ti/DBP/Collagen surface (tested in our previous work), suggest titanium modified by this layer by layer technique has the potential application for medical implants. [Copyright &y& Elsevier]

• The effects of Cu or Zn on the fluidity of A357 alloy were investigated. • With increase of Cu or Zn content, the fluidity of A357 alloy decreased. • With increase of Cu or Zn, the solidification temperature range increased. • The coarse grain is not the main reason for the fluidity to deteriorate. Excellent fluidity is an essential condition for Al-Si-Mg alloy (like A357) to make large thin-walled and complex structure castings, but t here is no research about the effects of Cu or Zn on the fluidity of Al-Si-Mg alloys. Under sand casting conditions, the effects of Cu or Zn on the fluidity of A357 were investigated through spiral fluidity resin sand molds, DSC, polarizing microscope and SEM. The results showed that with increase of Cu or Zn content, the solidification temperature range (T) of A357 alloy increased, and the fluidity decreased. With Cu or Zn addition, the grain size of A357 alloy increased, but the coarse grain is not the main reason for the fluidity to deteriorate. [ABSTRACT FROM AUTHOR]

• As for grains of Al-Si-Mg alloy, the poisoning effect of Zr and Ti-B occurred. • As for grains of Al-Si-Mg alloy, the poisoning effect of Sc and Ti-B was studied. • The order of grain size was A357 (Al-Si-Mg alloy) < A357 + Zr < A357 + Sc. • The content of Ti as nucleation cores in the melt decreased. • The poisoning occurred in the nucleation stage of grains. The effects of Sc or Zr on the grains of Al-Si-Mg alloy with Al-Ti-B addition were investigated under sand casting conditions by a polarizing microscope, differential scanning calorimetry and scanning electron microscopy. The results showed that the order of grain size is Alloy 1 (A357) < Alloy 3 (A357 + Zr) < Alloy 2 (A357 + Sc), which meant that when Zr and Ti-B existed at the same time or Sc and Ti-B existed at the same time, the grain refinement effect of Zr, Sc and Ti-B can not be reflected, and the poisoning occurred. The order of the actual nucleation temperature of primary α-Al grains (T l) was Alloy 1 > Alloy 3 > Alloy 2. In Al-Si-Mg alloy with Ti-B, with added Sc or Zr, many intermetallic compounds containing Sc and Ti or Zr and Ti appeared, which meant that the content of Ti as nucleation cores in the melt decreased, and the poisoning occurred in the nucleation stage of grains. [ABSTRACT FROM AUTHOR]

Dichlorvos (DDVP), as a highly effective insecticide, is widely used in agricultural production. However, DDVP residue in foodstuffs adversely affects human health. Conventional instrumental analysis can provide highly sensitive and accurate detection of DDVP, while the need of bulky and expensive equipment limits their application in resource-poor areas and on-site detection. Therefore, the development of easily portable sensing platforms for convenient, rapid and sensitive quantification of DDVP is very essential for ensuring food safety. A portable colorimetric sensing platform for rapid and sensitive quantification of DDVP is developed based on nanozyme-participated highly efficient chromogenic catalysis. The Fe-Mn bimetallic oxide (FeMnOx) nanozyme possesses excellently oxidase-like activity and can efficiently catalyze oxidation of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) into a blue oxide with a very low Michaelis constant (K m) of 0.0522 mM. The nanozyme-catalyzed chromogenic reaction can be mediated by DDVP via inhibiting the acetylcholinesterase (AChE) activity. Thus, trace DDVP concentration-dependent color evolution is achieved and DDVP can be sensitively detected by spectrophotometry. Furthermore, a smartphone-integrated 3D-printed miniature lightbox is fabricated as the colorimetric signal acquisition and processing device. Based on the FeMnOx nanozyme and smartphone-integrated lightbox system, the portable colorimetric sensing platform of DDVP is obtained and it has a wide linear range from 1 to 3000 ng mL−1 with a low limit of detection (LOD) of 0.267 ng mL−1 for DDVP quantification. This represents a new portable colorimetric sensing platform that can perform detection of DDVP in foodstuffs with simplicity, sensitivity, and low cost. The work not only offers an alternative to rapid and sensitive detection of DDVP, but also provides a new insight for the development of advanced sensors by the combination of nanozyme, 3D-printing and information technologies. [Display omitted] • A nanozyme-based efficient chromogenic catalysis is used for dichlorvos assay. • The Fe-Mn bimetallic oxide nanozyme possesses excellently oxidase-like activity. • A portable smartphone-integrated sensing platform of dichlorvos is fabricated. • The sensing platform are applied to quantification of dichlorvos in foodstuffs. [ABSTRACT FROM AUTHOR]

The influence of the partial substitution of Fe by Mo on the magnetic behavior and the frequency dependencies of the complex magnetic permeability are studied in Fe85.6−xMoxZr3.3Nb3.3B6.8Cu1 alloys. With the increase of the Mo content, the crystallization temperature will increase. The spectra of real and imaginary parts of the complex permeability were measured in the frequency of 0.1 kHz to 1 MHz, the obtained permeability spectra shows typical features of domain wall relaxation dispersion. With the increase of the Mo content, the core loss will decrease and the relaxation frequency will increase obviously. [Copyright &y& Elsevier]

[Display omitted] • Fluorescent silicon nanoparticles were synthesized and used for BPA detection. • BPA detection is based on enzymatic oxidation-mediated fluorescence quenching. • The fluorescent method for BPA detection is convenient and sensitive. • The method is suitable for the determination of BPA in actual food samples. As a common raw material of industrial products, bisphenol A (BPA) is widely used in the production of food contact materials, and there is a high risk of exposure in food. However, BPA is a well-known endocrine disruptor and poses a serious threat to human health. Herein, a fluorescent sensing platform of BPA based on enzymatic oxidation-mediated fluorescence quenching of silicon nanoparticles (SiNPs) is established and used to the detection of BPA in food species. The SiNPs are prepared with a facile one-step synthesis and emit bright green fluorescence. BPA can be oxidized by horseradish peroxidase (HRP) and hydrogen peroxide (H 2 O 2) to form a product which can quench the fluorescence of SiNPs through electron transfer. There is a good linear relationship between the fluorescence intensity and BPA concentration in the range of 1–100 μM. Therefore, a fluorometry of BPA is established with a low limit of detection (LOD) of 0.69 μM. This method has been applied to the determination of BPA in mineral drinking water, orange juice, and milk with satisfactory results. The fluorescent sensor of BPA based on SiNPs has favorable application foreground in the field of food safety analysis. [ABSTRACT FROM AUTHOR]

The varied mechanisms of yttrium (Y) modifying a hypoeutectic Al–Si alloy under conditions of different cooling rates were investigated using solidification curves, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), transmission electron microscopy (TEM) equipped with energy dispersion X-ray detector (EDX) and high resolution transmission electron microscope (HRTEM). The results show that Y could modify the eutectic silicon of a hypoeutectic Al–Si alloy (A357), but the modification mechanism was different at variable cooling rates. At a low cooling rate, Y modified the eutectic silicon by introducing additional nucleation cores during the nucleation process. At a high cooling rate, Y modified the eutectic silicon by promoting the twin formation during its growth process. • The varied modification mechanism of yttrium (Y) on hypoeutectic Al–Si alloy at different cooling rates was investigated. • At low cooling rate, Y modified eutectic silicon through introducing more nucleation cores during its nucleation process. • At high cooling rate, Y modified eutectic silicon through promoting the formation of twins during its growth process. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract A series of ZrO 2 supports were treated by ammonia solution with different reflux digestion time, and loaded 25 wt% MoO 3 for sulfur-resistant CO methanation reaction by incipient-wetness impregnation method. The MoO 3 /ZrO 2 catalysts were also characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), infrared spectra of adsorbed pyridine (Py-IR). Compared to the undigested ZrO 2 , ZrO 2 with reflux digestion in ammonia solution could achieve more oxygen vacancies, less Lewis acidic sites, smaller crystalline MoO 3 and more amount of active sites. Generally, when the support reflux digested in ammonia solution exceed 12 h, the CO conversion of digested catalysts Mo/A-ZrO 2 - x h reached 60%, while the CO conversion of undigested catalysts was just 36% at the same reaction condition. [ABSTRACT FROM AUTHOR]

Abstract As a new class of promising fluorescent carbon nanomaterials, carbon dots (CDs) have been well developed in recent years for their excellent fluorescent properties, simple synthetic approaches, good biocompatibility and various detection applications, which can be expected to replace the tradition semi-quantum dots. This review aims presents the current progress in the development of CDs with an emphasis on fluorescent properties, synthetic approaches and applications in food safety. First, the fluorescent properties of CDs are briefly introduced. To seek more reasonable synthetic approaches, the characteristics of the diverse methods of CD synthesis are summarized. And then, applications of CDs as fluorescent probes in food safety are discussed, with emphasis on the determination of metal ions/anions, pesticides, veterinary drugs, bacteria, functional components and banned additives. Finally, the challenges, such as how to explain the diversity of fluorescent properties, and how to form a uniform synthesis procedure to improve the quantum yield (QY), for CDs are presented. Although CDs have found many applications in food safety, it is still a challenge to detect a specific target in complex samples. Therefore, combination with other biochemistry technology to exploit novel ligands against the specific target with high binding affinity and selectivity is vitally important for developing sensitive and specific sensing probes in the future. Graphical abstract fx1 Highlights • We reviewed 149 published articles to provide valuable information of CD-based sensor. • The fluorescence properties, synthesis, detection applications in foods are reviewed. • The merits/demerits of various synthesis and detection methods are fully discussed. • The detection principles for various food contaminants are illustrated by schematic. • The analytical parameters for different types of food contaminants are tabulated. [ABSTRACT FROM AUTHOR]

Herein, an ingenious Halbach ring-mediated magnetic filter (HRMF) for capture, sterilization, and detection of foodborne pathogenic bacteria is developed. A composite material with magnetic nanoparticles (MNP) as the core and coated with polydopamine (PDA) and polyethylenimine (PEI) is synthesized, namely MNP@PDA@PEI. Under a Halbach ring, MNP@PDA@PEI can form chains to generate HRMF. Due to the positively charged of PEI, the HRMF could capture the negatively charged bacteria from solution via electrostatic adsorption. Within the HRMF, sterilization performance could be achieved due to the photothermal effect of MNP@PDA@PEI after 5 min of near-infrared light irradiation. More importantly, the number of bacteria could be calculated by bioluminescence method for measuring ATP, which are released from bacteria after photothermal sterilization. Listeria monocytogenes is chosen as a typical bacterium to evaluate the function of HRMF. The time of whole process has been greatly reduced to 38 min. The capture efficiency is 98.63%, and sterilization rate can achieve 99.96% in real samples. The limit of detection is 10.04 CFU/mL, representing a 10-fold decrease compared with bioluminescence method alone. The proposed platform might open a new way for on-site real-time detection of foodborne pathogens, and hold potential to nondestructive sterilization in the food processing industry. [Display omitted] • A capture, sterilization, and detection of pathogenic bacteria platform is developed. • This platform is based on Halbach Ring-mediated magnetic filter. • The capture and sterilization rate of HRMF are 98.63% and 99.96%, respectively. • The platform facilitates a ten-fold increase in detection sensitivity. • The HRMF opens a new way for on-site real-time detection of pathogens. [ABSTRACT FROM AUTHOR]

The introduction of organic additives rich in OH groups, such as citric acid, glucose and d -sorbitol, in nickel nitrate impregnation solutions is an efficient way to minify the size of NiO particles. The organic additives promote the wettability of the impregnation solution during solvent evaporation with increasing viscosity continuously, rather than act as ligands to Ni 2+ . This let Ni species are loaded into the micropores of support KIT-6, which can hinder the aggregation of Ni particles under severe conditions, e.g. thermal treatment at 650 °C. These organic additives can insulate the blocks of Ni species from each other during combustion without affecting their reducibility significantly, and result in a fairly high Ni dispersion. This kind of Ni-based catalysts possess excellent CO methanation catalytic performance: high CH 4 selectivity ( ca. 96% at 350 °C), great thermostability and long-term stability. [ABSTRACT FROM AUTHOR]

• The combustion and emission characteristics of FAME and HCB blends were investigated. • The D80H20 reduces BSFC, NO x and THC emissions by 4.15%, 5.42% and 6.52% respectively compared to D100. • D80H20 has more cost-effective than D80B20. • Model 11 performs best from a combined economy and emission characteristics perspective. Clean and renewable biodiesel demonstrates excellent potential for replacing fossil-based fuels and reducing CO 2 emissions. However, comparative studies on the applicability of fatty acid methyl ester and hydrogenated catalytic biodiesel still need to be included in practical application conditions of light-duty engines. Therefore, a comparative study on the combustion and emission performance of fatty acid methyl ester/diesel and hydrogenated catalytic biodiesel/diesel blends was conducted based on the World Harmonized Steady State Cycle in this research. The results show that except for the idling condition Region E, compared with D100, D80H20 has lower CA50 and ignition delay period, higher maximum cylinder pressure; while D80B20 has lower CA10, lower maximum cylinder pressure. The brake specific fuel consumption of all fuels is the lowest in mode 10, and the brake specific fuel consumption of D80B20 is 1.49% higher than that of D100. While D80H20 is 0.86% lower than that of D100. In Mode 8, NO x and CO 2 emissions were the lowest for all fuels, and compared to D100, NO x and CO 2 emissions were 4.7%, 3.8%, 4.83%, and 2.81% lower for D80H20 and D80B20, respectively. The brake specific fuel consumption, NO x , and THC emissions of D80H20 were reduced by 4.15%, 5.42%, and 6.52%, respectively, compared to D100 in all models, while the NO x , THC and CO 2 emissions of D80B20 were reduced by 6.9%, 23.1%, and 4.9%, respectively. Relative to D80B20, D80H20 has a better economy, but the emission problem cannot be ignored. Model 11 performs best from a combined economy and emission characteristics perspective. [ABSTRACT FROM AUTHOR]

In this paper, a portable fluorescence-based functional hydrogel loaded with β- d -glucose pentaacetate (β-D-GP) is designed for high-sensitive quantification of amine vapor and visual monitoring of freshness of shrimp. We found for the first time that amine vapor can mediate β-D-GP to generate photoluminescent polymer-carbon nanodots (PCNDs) with good optical properties. On this basis, a functional hydrogel sensing platform is simply formed by solidifying β-D-GP in agarose hydrogels. When exposure to the volatile amines released from the spoilage of shrimp, β-D-GP in hydrogel is immediately mediated by amines to generate PCNDs, resulting in obvious fluorescence-based color variation of functional hydrogel. Notably, a smartphone is used to obtain digital photographs and RGB (Red/Green/Blue) information of hydrogels for on-site quantitative analysis. The gray value of G/(R + B) of hydrogel shows good linearity with trimethylamine (TMA) vapor concentration in the range of 0–59.49 × 10−9 mol dm−3. More importantly, the G/(R + B) value of functional hydrogel is successfully used to assess the freshness of shrimp. Consequently, this strategy provides a low-cost, portable fluorescence analysis device with promising applications in achieving high-sensitive, nondestructive, and on-site food safety evaluation of animal-derived aquatic products. [Display omitted] • Amine vapor can mediate β- d -glucose pentaacetate to generate photoluminescent polymer-carbon nanodots. • A portable fluorescence-based functional hydrogel loaded with β- d -glucose pentaacetate is designed. • Photoluminescent polymer-carbon nanodots are generated in situ in hydrogels without additional synthesis. • Introduction of smartphone combined with RGB analysis greatly improves the practicality of monitoring on-site. • The hydrogel platform achieves highly sensitive, nondestructive and on-site monitoring of shrimp freshness. [ABSTRACT FROM AUTHOR]

The effects of two-step annealing on the microstructures and soft magnetic properties of nanocrystalline Fe86Zr7B6Cu1 ribbons were studied. Two-step annealing results in a marked decrease of grain size and a distinct improvement of soft magnetic properties with respect to conventional annealing at 600 °C for 1 h. Bcc α-Fe with the grain size of 8 nm is formed in ribbon after it is pre-annealed at 750 °C for 2 min followed by annealing at 600 °C for 58 min. Its coercive force Hc, initial permeability μi, and relaxation frequency f0 are 1.5 A/m, 6.15×104, and 8.9×104 Hz, respectively. The decrease of grain size may result from a larger value of the nucleation rate obtained during the initial stage of crystallization by annealing amorphous ribbon at higher temperatures for short duration. But pre-annealing at 800 °C leads to the decrease of soft magnetic properties because of the formation of Fe3Zr. [Copyright &y& Elsevier]

The variation in suspended sediment concentration (SSC) has an important impact on the protection of estuarine shoal wetlands and the maintenance of waterways. Typhoons (tropical cyclones), one of the most severe meteorological disasters, frequently occur along the southeastern coasts of China and substantially affect the spatial-temporal distribution of SSC in the Yangtze Estuary. In this study, the spatial-temporal distribution of SSC was observed at high frequency through hourly geostationary satellite remote sensing during four typhoon events, namely, Typhoons Damrey/Saola (August 2012), Soulik (July 2013), Matmo (July 2014) and Dujuan (September 2015). Such observation is difficult to achieve through in situ approaches due to the unsafe working conditions created by typhoon winds. Moreover, wind speed, wave height and period, and bottom shear stress (BSS) data combined with turbidity data were used to analyze the causes of typhoon-induced SSC variations. The results indicated that the average wind-driven significant wave height during typhoons was 2.1-fold higher than that in pre-typhoon periods. In the lower mouth of the Yangtze Estuary and in Hangzhou Bay, the SSC increased by 0.14–0.33 g/L, whereas in the upper mouth, the SSC was less affected by wind. The significant increase in SSC persisted for 1–2 days following typhoon transit. With the assistance of the FVCOM model, it was observed that the enhanced wave-current dynamics and increased BSS during the typhoons were the main reasons for the sharp increase in SSC. Moreover, it was inferred from the satellite images that sediment exchange occurs between channels and shoals during a typhoon, which affects the SSC distribution for up to one month. • Suspended sediment concentrations were observed with high frequency by in-situ data and ocean color satellite GOCI. • Suspended sediment concentration variations in four typhoon events were analyzed with the assistance of the FVCOM model. • Sediment exchange between channels and shoals was deduced based on GOCI observation. [ABSTRACT FROM AUTHOR]

Magnetic pulse welding (MPW) is a cost-effective solid-state welding technology, which is mainly used in the lap joining of similar and dissimilar materials. It has broad application prospects in aerospace, automotive and appliance industries. In this paper, the corrosion-resistant 5052 aluminum alloy (Al) and the high-strength 2A66 aluminum-lithium alloy (Al Li) were joined by MPW. The interface microstructure of Al/Al Li welded joints was characterized and analyzed by scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the welding interface was composed of four zones: the molten zone with porous structure, the shear molten zone, the sine wave interface zone and the flat interface zone. It can be seen that the shear molten zone consisted of ultra-fine equiaxed grains, which were formed by the rapid melting and solidification of Al alloy at the interface. A fine grain layer was observed at the sine wave interface, and some precipitated phases disappeared inside the fine grains. These were caused by dynamic recrystallization and a certain temperature rise at the interface. The precipitated phases near the fine grain layer only deformed to a certain extent and did not dissolve. This showed that the grains outside the fine grain layer were only subjected to a certain impact without severe deformation and temperature rise, reflecting that the heat-affected zone (HAZ) of MPW was very narrow. Unlabelled Image • The microstructure evolution at the interface of Al/Al Li MPW joint was characterized and analyzed by SEM and TEM. • The welding interface consisted of a molten zone with porous, a shear molten zone, a wave interface and a flat interface. • The precipitates in shear molten zone and fine-grained band were dissolved, and those near the wave interface were deformed. [ABSTRACT FROM AUTHOR]

Background: Oritavancin is a new generation of semi-synthetic glycopeptide antibiotics against Gram-positive bacteria, which served as the first and only antibiotic with a single-dose therapeutic regimen to treat ABSSSI. A naturally occurring glycopeptide A82846B is the direct precursor of oritavancin. However, its application has been hampered by low yields and homologous impurities. This study established a multi-step combinatorial strategy to rationally construct a high-quality and high-efficiency biosynthesis system for A82846B and systematically optimize its fermentation process to break through the bottleneck of microbial fermentation production., Results: Firstly, based on the genome sequencing and analysis, we deleted putative competitive pathways and constructed a better A82846B-producing strain with a cleaner metabolic background, increasing A82846B production from 92 to 174 mg/L. Subsequently, the PhiC31 integrase system was introduced based on the CRISPR-Cas12a system. Then, the fermentation level of A82846B was improved to 226 mg/L by over-expressing the pathway-specific regulator StrR via the constructed PhiC31 system. Furthermore, overexpressing glycosyl-synthesis gene evaE enhanced the production to 332 mg/L due to the great conversion of the intermediate to target product. Finally, the scale-up production of A82846B reached 725 mg/L in a 15 L fermenter under fermentation optimization, which is the highest reported yield of A82846B without the generation of homologous impurities., Conclusion: Under approaches including blocking competitive pathways, inserting site-specific recombination system, overexpressing regulator, overexpressing glycosyl-synthesis gene and optimizing fermentation process, a multi-step combinatorial strategy for the high-level production of A82846B was developed, constructing a high-producing strain AO-6. The combinatorial strategies employed here can be widely applied to improve the fermentation level of other microbial secondary metabolites, providing a reference for constructing an efficient microbial cell factory for high-value natural products., (© 2024. The Author(s).)

Lignin in biomass plays significant role in substitution of synthetic polymer and reduction of energy expenditure, and the lignin content was usually determined by wet chemical methods. However, the methods' heavy workload, low efficiency, huge consumption of chemicals and use of toxic reagents render them unsuitable for sustainable development and environmental protection. Chinese fir, a prevalent angiosperm tree, holds immense importance for various industries. Since our previous work found that Raman spectroscopy could accurately predict the lignin content in poplar, we propose that the lignin content of Chinese fir can be estimated by similar strategy. The results suggested that the peak at 2895 cm -1 is the optimal choice of internal standard peak and algorithm of XGBoost demonstrates the highest accuracy among all algorithms. Furthermore, transfer learning was successfully introduced to enhance the accuracy and robustness of the model. Ultimately, we report that a machine learning algorithm, combining transfer learning with XGBoost or LightGBM, offers an accurate, high-efficiency and environmental friendly method for predicting the lignin content of Chinese fir using Raman spectra., Competing Interests: Declaration of competing interest The authors declare no competing interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Chestnut plants ( Castanea ) are important nut fruit trees worldwide. However, little is known regarding the genetic relationship and evolutionary history of different species within the genus. How modern chestnut plants have developed local adaptation to various climates remains a mystery. The genomic data showed that Castanea henryi first diverged in the Oligocene ~31.56 million years ago, followed by Castanea mollissima, and the divergence between Castanea seguinii and Castanea crenata occurred in the mid-Miocene. Over the last 5 million years, the population of chestnut plants has continued to decline. A combination of selective sweep and environmental association studies was applied to investigate the genomic basis of chestnut adaptation to different climates. Twenty-two candidate genes were associated with temperature and precipitation . We also revealed the molecular mechanism by which CmTOE1 interacts with CmZFP8 and CmGIS3 to promote the formation of non-glandular trichomes for adaptation to low temperature and high altitudes. We found a significant expansion of CER1 genes in Chinese chestnut ( C. mollissima ) and verified the CmERF48 regulation of CmCER1.6 adaptation to drought environments. These results shed light on the East Asian chestnut plants as a monophyletic group that had completed interspecific differentiation in the Miocene, and provided candidate genes for future studies on adaptation to climate change in nut trees., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nanjing Agricultural University.)

Ultrafast electron diffraction has been proven to be a powerful tool for the study of coherent acoustic phonons owing to its high sensitivity to crystal structures. However, this sensitivity leads to complicated behavior of the diffraction intensity, which complicates the analysis process of phonons, especially higher harmonics. Here, we theoretically analyze the effects of photoinduced coherent transverse and longitudinal acoustic phonons on electron diffraction to provide a guide for the exploitation and modulation of coherent phonons. The simulation of the electron diffraction was performed in 30-nm films with different optical penetration depths based on the atomic displacements obtained by solving the wave equation. The simulation results exhibit a complex relationship between the frequencies of the phonons and diffraction signals, which highly depends on the laser penetration depth, sample thickness, and temporal stress distribution. In addition, an intensity decomposition method is proposed to account for the in-phase oscillation and high harmonics caused by inhomogeneous excitation. These results can provide new perspectives and insights for a comprehensive and accurate understanding of the lattice response under coherent phonons., Competing Interests: The authors have no conflicts to disclose., (© 2023 Author(s).)

Pseudostellaria heterophylla is one of the traditional medicines in China. From 2020 to 2022, postharvest wet root rot disease was observed with an incidence of 2~5% on the tuberous roots of the harvested P. heterophylla in Zherong county, Fujian province, China, which usually occurs under damp and unventilated conditions. The symptoms of the disease were as follows: white mycelia grew on the surface of tuberous root initially and gradually wrapped around the roots, the internal root tissue turned yellow and became wet decay finally. To identify the causal agent, a total of 20 samples with symptomatic tuberous roots were collected. Small pieces (3 mm2) were treated by surface disinfection with 75% ethanol and 1% NaOCl, then rinsed 3 times with sterile water. These treated pieces were transferred onto potato dextrose agar (PDA) and incubated at 25°C in the dark for 7 d. Ten pure cultures were obtained using single-spore isolation method. The fungus colonies initially produced white aerial mycelium, subsequently exhibited yellow pigmentation. Mycelia were consisted of smooth, hyaline, branched, and septate hyphae. The conidia were solitary or clustered, brown or dark brown, smooth, ellipsoidal to spherical, 6.66 (5.50-7.81)×5.65 (4.17-7.22) µm (n=50) in size. The conidiophores were hyaline or pale brown and produced conidiogenous cells, which were pale brown, smooth, ampulliform, and 10.14 (8.82-15.30) um long (n=50). Based on these morphological characteristics, the fungus was identified as the genus Apiospora (Arthrinium). The rDNA-ITS region and partial β-tubulin gene (BenA) were amplified using the primers ITS1/ITS4 (White et al. 1990) and Bt2a/Bt2b (Glass and Donaldson 1995), respectively. The sequences of isolates FJAT-32563 and FJAT-32564 were deposited in GenBank (ITS, OM920984 and OM920985; BenA, OM953823 and OM953824). All sequences had more than 99% similarity with those of A. arundinis strain CBS:106.12 (ITS, KF144883; BenA, KF144973). In the multilocus phylogenetic analysis (ITS + BenA), the two isolates clustered together with other strains of A. arundinis with 100% bootstrap support. The isolates were therefore identified as A. arundinis based on both morphological and molecular characteristics. To confirm the pathogenicity, fresh tuberous roots were selected and surface disinfected, then the roots were immersed with a quarter length in the conidial suspension (106/mL) for 30 min, whereas the control roots were immersed with sterile water (n=30). They were placed in petri dish with wet filter paper at 25±2℃, maintaining 80% relative humidity in the dark. The white aerial mycelium appeared at 5 days after inoculation, and wet root rot decaying occurred after inoculation for 21 days. The symptoms were similar to those described above, whereas the control roots were asymptomatic. The same fungus was re-isolated from the infected roots, showing similar morphological characteristics and molecular traits. Koch's postulates were completed and the pathogenicity test for the isolates has been repeated thrice. Previously, A. arundinis was reported to infect peach and sugarcane (Ji et al. 2020; Liao et al. 2022). To our knowledge, this is the first report of A. arundinis causing wet root rot of P. heterophylla in China. The disease would be a potentially new threat to this medicinal plant.

This study proposes a rational strategy for the design, fabrication and system integration of the humanoid intelligent display platform (HIDP) to meet the requirements of highly humanized mechanical properties and intelligence for human-machine interfaces. The platform's sandwich structure comprises a middle light-emitting layer and surface electrodes, which consists of silicon elastomer embedded with phosphor and silk fibroin ionoelastomer, respectively. Both materials are highly stretchable and resilient, endowing the HIDP with skin-like mechanical properties and applicability in various extreme environments and complex mechanical stimulations. Furthermore, by establishing the numerical correlation between the amplitude change of animal sounds and the brightness variation, the HIDP realizes audiovisual interaction and successful identification of animal species with the aid of Internet of Things (IoT) and machine learning techniques. The accuracy of species identification reaches about 100% for 200 rounds of random testing. Additionally, the HIDP can recognize animal species and their corresponding frequencies by analyzing sound characteristics, displaying real-time results with an accuracy of approximately 99% and 93%, respectively. In sum, this study offers a rational route to designing intelligent display devices for audiovisual interaction, which can expedite the application of smart display devices in human-machine interaction, soft robotics, wearable sound-vision system and medical devices for hearing-impaired patients., (© 2023. Shanghai Jiao Tong University.)

Morphing in creatures has inspired various synthetic polymer materials that are capable of shape shifting. The morphing of polymers generally relies on stimuli-active (typically heat and light active) units that fix the shape after a mechanical load-based shape programming. Herein, we report a strategy that uses a mechanochemically active 2,2'-bis(2-phenylindan-1,3-dione) (BPID) mechanophore as a switching unit for mechanochemical morphing. The mechanical load on the polymer triggers the dissociation of the BPID moiety into stable 2-phenylindan-1,3-dione (PID) radicals, whose subsequent spontaneous dimerization regenerates BPID and fixes the temporary shapes that can be effectively recovered to the permanent shapes by heating. A greater extent of BPID activation, through a higher BPID content or mechanical load, leads to higher mechanochemical shape fixity. By contrast, a relatively mechanochemically less active hexaarylbiimidazole (HABI) mechanophore shows a lower fixing efficiency when subjected to the same programing conditions. Another control system without a mechanophore shows a low fixing efficiency comparable to the HABI system. Additionally, the introduction of the BPID moiety also manifests remarkable mechanochromic behavior during the shape programing process, offering a visualizable indicator for the pre-evaluation of morphing efficiency. Unlike conventional mechanical mechanisms that simultaneously induce morphing, such as strain-induced plastic deformation or crystallization, our mechanochemical method allows for shape programming after the mechanical treatment. Our concept has potential for the design of mechanochemically programmable and mechanoresponsive shape shifting polymers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Antibiotics are double-edged swords. Although antibiotics are used to inhibit pathogenic bacteria, they also run the risk of destroying some of the healthy bacteria in our bodies. We examined the effect of penicillin on the organism through a microarray dataset, after which 12 genes related to immuno-inflammatory pathways were selected by reading the literature and validated using neomycin and ampicillin. The expression of genes was measured using qRT-PCR. Several genes were significantly overexpressed in antibiotic-treated mice, including CD74 and SAA2 in intestinal tissues that remained extremely expressed after natural recovery. Moreover, transplantation of fecal microbiota from healthy mice to antibiotic-treated mice was made, where GZMB, CD3G, H2-AA, PSMB9, CD74, and SAA1 were greatly expressed; however, SAA2 was downregulated and normal expression was restored, and in liver tissue, SAA1, SAA2, SAA3 were extremely expressed. After the addition of vitamin C, which has positive effects in several aspects, to the fecal microbiota transplantation, in the intestinal tissues, the genes that were highly expressed after the fecal microbiota transplantation effectively reduced their expression, and the unaffected genes remained normally expressed, but the CD74 gene remained highly expressed. In liver tissues, normally expressed genes were not affected, but the expression of SAA1 was reduced and the expression of SAA3 was increased. In other words, fecal microbiota transplantation did not necessarily bring about a positive effect of gene expression restoration, but the addition of vitamin C effectively reduced the effects of fecal microbiota transplantation and regulated the balance of the immune system., Competing Interests: The authors declare there are no competing interests., (©2023 Huang et al.)

Hundreds of proteins work together in microorganisms to coordinate and control normal activity in cells. Their degradation is not only the last step in the cell's lifespan but also the starting point for its recycling. In recent years, protein degradation has been extensively studied in both eukaryotic and prokaryotic organisms. Understanding the degradation process is essential for revealing the complex regulatory network in microorganisms, as well as further artificial reconstructions and applications. This review will discuss several studies on protein quality-control family members Lon, FtsH, ClpP, the proteasome in Streptomyces, and a few classical model organisms, mainly focusing on their structure, recognition mechanisms, and metabolic influences.

Dual-mode sensing with a two-signal read-out is conducive to the improvement of detection accuracy. Herein, a fluorescent and scattering dual-mode chemosensor for tetracycline (TC) is proposed based on a carbon dot@cerium-guanosine monophosphate (CD@GMP-Ce) coordination polymer network. The inexpensive CD@GMP-Ce was prepared by exploiting the adaptive inclusion capability of coordination polymers and possessed remarkable fluorescence and strong Rayleigh scattering. The functional CD@GMP-Ce demonstrated fluorescence and scattering, the two optical-signal responses to TC simultaneously. Based on TC-specific fluorescence and scattering decline, the dual-mode detection of TC was established and the probe's detection limits were 43 nM in the fluorescence mode and 77 nM in the scattering mode, respectively. Furthermore, the potential application of the dual-mode sensor was verified by measuring TC in milk and tap-water samples. The study not only provides a new perspective for the development of assay methods for TC but also expands the applications of cerium coordination polymers.

Without an effective strategy for targeted therapy, glioblastoma is still incurable with a median survival of only 15 months. Both chronic inflammation and epigenetic reprogramming are hallmarks of cancer. However, the mechanisms and consequences of their cooperation in glioblastoma remain unknown. Here, we discover that chronic inflammation governs H3K27me3 reprogramming in glioblastoma through the canonical NF-κB pathway to target EZH2. Being a crucial mediator of chronic inflammation, the canonical NF-κB signalling specifically directs the expression and redistribution of H3K27me3 but not H3K4me3, H3K9me3 and H3K36me3. Using RNA-seq screening to focus on genes encoding methyltransferases and demethylases of histone, we identify EZH2 as a key methyltransferase to control inflammation-triggered epigenetic reprogramming in gliomagenesis. Mechanistically, NF-κB selectively drives the expression of EZH2 by activating its transcription, consequently resulting in a global change in H3K27me3 expression and distribution. Furthermore, we find that co-activation of NF-κB and EZH2 confers the poorest clinical outcome, and that the risk for glioblastoma can be accurately molecularly stratified by NF-κB and EZH2. It is notable that NF-κB can potentially cooperate with EZH2 in more than one way, and most importantly, we demonstrate a Synergistic effect of cancer cells induced by combinatory inhibition of NF-κB and EZH2, which both are frequently over-activated in glioblastoma. In summary, we uncover a functional cooperation between chronic inflammation and epigenetic reprogramming in glioblastoma, combined targeting of which by inhibitors guaranteed in safety and availability furnishes a potent strategy for effective treatment of this fatal disease., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

In this study, regularization algorithms (RR, LR, and ENR), classical ML algorithms (SVR, DT, and RF), and advanced GBM algorithms (LightGBM, CatBoost, and XGBoost) were applied to build the holocellulose content predictive models of poplar based on features extracted from Raman spectra. Evaluation results of models indicate that classical ML algorithms show higher predictive accuracy than regularization algorithms, and the advanced GBM algorithms better than the classical ML algorithms. Furthermore, models built by CatBoost and XGBoost can estimate holocellulose content with high predictive accuracy of test R 2 above 0.93 and test RMSE less than 0.29%. It provides the heretofore best precision of holocellulose content predictive model based on Raman spectroscopy so far for our knowledge. Therefore, it is suggested that Raman spectroscopy coupled with ML algorithms is a promising tool for predicting the holocellulose content in poplar which can be applied in large-scale tree genetic and breeding programs., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Alzheimer's disease (AD) is the most common form of dementia worldwide. Previous studies have reported that sevoflurane, a frequently used anesthetic, can induce cognitive impairment in preclinical and clinical settings. However, the mechanism underlying the development of this neurotoxicity is currently unclear. Methods: Seven-month-old APP/PS1 mice were placed in an anesthesia induction box containing 3% sevoflurane in 100% O 2 for 6 h, while BV2 cells were cultured with 4% sevoflurane for 6 h. Pyroptosis and tau protein expression in excised hippocampus tissues and cells were measured using Western blotting and immunofluorescence assay. Caspase-1 and NLRP3 were knocked out in BV2 microglia using CRISPR/Cas9 technology to determine whether they mediate the effects induced by sevoflurane. Results: Sevoflurane directly activated caspase-1 to induce pyroptosis in the mouse model of AD via NLRP3 and AIM2 activation. In addition, sevoflurane mediated cleavage of gasdermin D (GSDMD) but not gasdermin E (GSDME), promoted the biosynthesis of downstream interleukin-1 β and interleukin-18, and increased β -amyloid (A β ) deposition and tau phosphorylation. The nontoxic caspase-1 small-molecule inhibitor VX-765 significantly inhibited this activation process in microglia, while NLRP3 deletion suppressed sevoflurane-induced caspase-1 cleavage and subsequently pyroptosis, as well as tau pathology. Furthermore, silencing caspase-1 alleviated the sevoflurane-induced release of IL-1β and IL-18 and inhibited tau-related enzymes in microglia. Conclusion: This study is the first to report that clinical doses of sevoflurane aggravate the progression of AD via the NLRP3/caspase-1/GSDMD axis. Collectively, our findings elucidate the crucial mechanisms of NLRP3/caspase-1 in pyroptosis and tau pathogenesis induced by sevoflurane and suggest that VX-765 could represent a novel therapeutic intervention for treating AD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tian, Xing, Gao, Zhang, Song, Tian and Dai.)

Raman spectroscopy has been widely used in the research of fibrous proteins because of the insensitivity to moisture, less amount of sample, and better signal-to-noise ratio. In recent years, Raman spectroscopy is adopted to investigate the secondary structures of solid or aqueous protein, the conformation transition under different conditions (concentration, temperature, pressure, pH, chemical modification, external force, etc.), the orientation of the molecular chains, and some important chemical bonds. Here, we will introduce the methods for using Raman spectroscopy to analyze the conformation and orientation of samples, which would be an efficient method to get the "structure-property" relationship., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

The Muli area is the only permafrost region on the Chinese mainland wherein gas hydrates have been discovered. The gas hydrates are present in the fractures and pore spaces of the host rocks with a lamellar or micro-disseminated structure. By combining conventional and image logs, we describe the thickness of the permafrost layer and the well log responses of the gas hydrate reservoir, and calculate the porosity and gas hydrate saturation. We then analyze the advantages and disadvantages of different logging methods for evaluating gas hydrate reservoirs. Our results indicate that (1) gas hydrates are present below the permafrost in the Muli area, (2) gas hydrates predominantly occur in rock fractures, (3) the apparent resistivity is sensitive to gas hydrates present in pore spaces, and both apparent resistivity and acoustic logs are sensitive to gas hydrates present in fractures, (4) a density log is more appropriate for calculating porosity, and (5) gas hydrate saturation can be effectively calculated by the Archie equation, the modified Archie equation, and the Indonesian equation.

Red emissive carbon dots (CDs) have drawn more and more attention due to their good organ penetration depth and slight biological tissue photodamage. Herein, the fluorescent CDs with red emission were synthesized by the facile one-pot hydrothermal treatment of citric acid and neutral red and they show red fluorescence both in aqueous solution and solid state. The solution of CDs exhibits the quantum yield of 12.1%, good stability against photobleaching, and low cytotoxicity. As-prepared CDs can be used as a fluorescent probe for peculiar detection of Pt 2+ , Au 3+ , and Pd 2+ . Furthermore, the CDs show excellent biocompatibility, which were successfully used as hopeful bioimaging and biosensing of noble metal ions in PC12 cells and zebrafish.

Nuclear factor-kappaB (NF-kappaB) has been recognized to play a critical role in cell survival and inflammatory processes. It has become a target for intense drug development for the treatment of cancer, inflammatory, and autoimmune diseases. Here, we describe a potent NF-kappaB inhibitor, eriocalyxin B (Eri-B), an ent-kauranoid isolated from Isodon eriocalyx, an anti-inflammatory remedy. The presence of two alpha,beta-unsaturated ketones give this compound the uniqueness among the ent-kauranoids tested. Eri-B inhibited the NF-kappaB transcriptional activity but not that of cAMP response element-binding protein. It suppressed the transcription of NF-kappaB downstream gene products including cyclooxygenase-2 and inducible nitric-oxide synthase induced by tumor necrosis factor-alpha or lipopolysaccharide in macrophages and hepatocarcinoma cells. Chromatin immunoprecipitation assay indicated that Eri-B selectively blocked the binding between NF-kappaB and the response elements in vivo without affecting the nuclear translocation of the transcription factor. Down-regulation of the endogenous p65 protein sensitized the cells toward the action of the compound. Furthermore, in vitro binding assays suggested that Eri-B reversibly interfered with the binding of p65 and p50 subunits to the DNA in a noncompetitive manner. In summary, this study reveals the novel action of a potent NF-kappaB inhibitor that could be potentially used for the treatment of a variety of NF-kappaB-associated diseases. Modification of the structure of this class of compounds becomes the key to the control of the behavior of the compound against different cellular signaling pathways.

A tylophorine analogue, DCB-3503, has been shown to have potent activity against tumor growth in vitro and in vivo, as well as activity in an autoimmune disease model in vivo. This study focuses on investigating the mechanisms responsible for antitumor activity of DCB-3503. The concentrations for inhibiting 50% growth/colony formation ability are 50/162 and 40/149 nmol/L for PANC-1 and HPAC cells, respectively. The growth inhibition effects are associated with DCB-3503-induced reprogramming of tumor cells. DCB-3503 could interfere with cell cycle progression. Several cell cycle regulatory proteins, including cyclin D(1), are down-regulated by DCB-3503. Using several different transcription elements coupled with a reporter gene, it was found that the nuclear factor-kappaB (NF-kappaB) signaling pathway is the most sensitive pathway mediator affected by DCB-3503. The inhibition of NF-kappaB activity is dependent on the down-regulation of nuclear phosphorylated p65, a component of the active form of the NF-kappaB complex. Such a decrease in nuclear phosphorylated p65 can be reversed by a proteosome inhibitor. Furthermore, the activity and protein expression of nuclear IkappaB kinase alpha, which is responsible for p65 phosphorylation, is suppressed and down-regulated in cells treated with DCB-3503. In summary, DCB-3503 could affect cell cycle regulatory proteins and is a potent modulator of NF-kappaB function. It is a potentially useful compound in the management of cancers in which cyclin D1 overexpression and high NF-kappaB activity play a pivotal role.