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The high integration density of microelectronic devices leads to local heat accumulation, and effective heat dissipation and signal transmission of packaging materials have become the primary issues to be solved. However, existing polymer materials have difficulty meeting the requirements due to their unsatisfactory thermal conductivity and thermal expansion properties. In this work, we proposed the use of digital light processing (DLP) printing technology to construct a triply periodic minimum surface (TPMS) skeleton, and a continuous and efficient heat conduction path was successfully constructed in epoxy resin by impregnating h-BN on the skeleton surface. When the loading of h-BN was 20 vol%, the thermal conductivity of the TPMS(SiO 2)@BN/EP(BN) composites was 1.86 W/(m·K), which was 786 % higher than that of pure epoxy resin. In addition, the thermal expansion coefficient of the composites decreased by more than 70 %. At the test frequencies of 3∼10 MHz, the composites showed stable dielectric properties, and the dielectric constant was always maintained in a low range, between 3.85 and 4.15. This work has realized the transformation of the method for constructing a heat conduction path from disordered to ordered and from random to repeatable. This provides a new strategy for the selection of microelectronic packaging materials. [ABSTRACT FROM AUTHOR]

Mercury emission from industrial wastewater has a great impact on the aquatic environment but is not well studied. Inventory analysis, decoupling and decomposition methods have been conducted based on the China Pollution Source Census dataset, which combines industry removal efficiencies to calculate mercury emissions from industrial wastewater in 340 cities in China during 2000–2010. The results show that over these 11 years, total mercury emissions and per capita mercury emissions increased by approximately 5 times, while the emission intensity increased by only about 3%. From 2000 to 2010, only 0.59% of cities showed strong decoupling between economic growth and mercury emissions, and 37.65% of cities showed weak decoupling, whereas 38.82% of cities showed negative decoupling. We attribute the decoupling of economic development and emissions in individual cities to several socioeconomic factors and find that a decline in emission intensity is the main driver. The Gini coefficient indicates a significant imbalance between cities' emissions, but this situation improved during 2000–2010. The objective of this article is to provide a historical perspective on the situation of mercury emissions from wastewater in China, thereby contributing' to the broader understanding of industrial pollution. [Display omitted] • Wastewater mercury emissions in Chinese cities were calculated from 2000 to 2010. • Only 4.41% of Chinese cities achieved a decoupling of GDP from mercury emissions. • The decline in emission intensity is vital to achieving decoupling. • There is a significant imbalance between cities' emissions. [ABSTRACT FROM AUTHOR]

Photocatalysis has a broad prospect for generating H 2 and reactive oxygen species. In this study, porous nanotubular g-C 3 N 4 /TiO 2 photocatalysts were obtained via electrospinning combined with an innovative vapor deposition approach. The waste foam was used as the precursor material for TiO 2 nanotubes, reducing production cost and benefiting resource recovery. The modification of g-C 3 N 4 onto TiO 2 nanotubes provided extensive active sites with an increased specific surface area and produced the heterojunction to improve charge separation. The g-C 3 N 4 /TiO 2 nanotubes displayed remarkable photocatalytic effects in the degradation of organic dye with a removal efficiency of 93.4% and H 2 evolution reaction performing at 4122 μmol·g−1·h−1 under simulated sunlight. Photocatalytic activation product analyses and density functional theory (DFT) calculations demonstrated a possible photogenerated carriers transfer pathway. This work provides a way to prepare multifunctional porous nanotubes using a facile synthesis method from abandoned resources with implications for environmental remediation and hydrogen generation. [Display omitted] • Waste foam was used as the precursor material for preparing TiO 2 nanotubes. • Porous nanotubular g-C 3 N 4 /TiO 2 photocatalysts were obtained via an innovative vapor deposition approach. • g-C 3 N 4 /TiO 2 displayed remarkable photocatalytic effects for pollutant degradation and hydrogen generation. • Mechanism of photon-generated charges separation and transfer was discussed. [ABSTRACT FROM AUTHOR]

The degradation of organic pollutant by photocatalytic technology is an emerging and effective approach to purify water resources. Herein, we reported a heterostructure with selective adsorption and photocatalysis for the efficient removal of organic pollutant. The photocatalyst was comprised of up-converting nanoparticle (UCNP) coated with Ag/Bi 2 O 3. The specific crystallinity of Bi 2 O 3 facilitated the selective adsorption of organic molecules with negative polarity, Ag nanoparticles loaded on Bi 2 O 3 promoted the visible light absorption, and the up-conversion property of UCNP turned near-infrared light into ultraviolet and visible light improving further light-harvesting efficiency in the whole solar spectrum. The adsorption process for organic pollutants over Ag/UCNP@Bi 2 O 3 obeyed the pseudo-second-order and the Langmuir isotherm models, and the maximum Langmuir adsorption capacity for tetracycline reached to 717.4 mg/g at pH 7. Meanwhile, the photocatalytic degradation rate of Ag/UCNP@Bi 2 O 3 for tetracycline (100 mg/L) achieved to 0.0037 min−1 under Xenon lamp irradiation after the adsorption equilibrium. This study provided a feasible strategy to develop photocatalysts with efficient adsorption and photocatalytic ability for organic pollutant from water. The schematic illustration of the photocatalytic mechanism of the Ag/UCNP@Bi 2 O 3 NPs, and the energy transfer mechanisms show the up-conversion process of Yb3+ and Tm3+ doped UCNPs under 980 nm excitation. [Display omitted] • The specific crystallinity of Bi 2 O 3 facilitated selective adsorption. • The interface interaction of Ag/Bi 2 O 3 significantly improved photocatalytic effect. • Up-conversion nanoparticle coupled with Ag/Bi 2 O 3 fulfill whole solar spectrum. • Tetracycline could be selectively adsorbed and further photodegraded. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fatty acid- and terpene-derived biofuels are ideal advanced transportation fuels. • Y. lipolytica is a valuable chassis for the overproduction of advanced biofuels. • Engineering Y. lipolytica to overproduce advanced biofuels is urgently needed. • Engineering strategies in Y. lipolytica for advanced biofuel overproduction are summarized. • Future perspectives in Y. lipolytica advanced biofuel production are prospected. Energy security and global climate change have necessitated the development of renewable energy with net-zero emissions. As alternatives to traditional fuels used in heavy-duty vehicles, advanced biofuels derived from fatty acids and terpenes have similar properties to current petroleum-based fuels, which makes them compatible with existing storage and transportation infrastructures. The fast development of metabolic engineering and synthetic biology has shown that microorganisms can be engineered to convert renewable feedstocks into these advanced biofuels. The oleaginous yeast Yarrowia lipolytica is rapidly emerging as a valuable chassis for the sustainable production of advanced biofuels derived from fatty acids and terpenes. Here, we provide a summary of the strategies developed in recent years for engineering Y. lipolytica to synthesize advanced biofuels. Finally, efficient biotechnological strategies for the production of these advanced biofuels and perspectives for future research are also discussed. [ABSTRACT FROM AUTHOR]

A Cu-coated Al 2 O 3 substrates which can be used for power modules are prepared via sintering and reduction of CuO–SiO 2 film onto the surface of Al 2 O 3 ceramic without precious metal brazing filler or high-vacuum equipment. This method has a significant cost advantage over the existing technology. Effects of oxygen partial pressure from sintering atmosphere and SiO 2 content on microstructure and mechanical properties of Cu/Al 2 O 3 interface are systematically investigated. Phase compositions and morphologies of sintered Cu 2 O layer, reduced Cu layer and reactive layer are characterized via X-ray diffraction and scanning electron microscopy. In addition, physicochemical changes within CuO–SiO 2 during sintering are characterized by thermogravimetry-differential scanning calorimeter. It is found that oxygen and SiO 2 can promote the generation of Cu 2 O–CuO–SiO 2 eutectic phase with low melting point upon sintering, which increases the thickness of reaction layer and the densification of Cu layer. The shear strength between the Cu layer and the Al 2 O 3 substrate is enhanced with the increase in Cu layer densification degree, while varying in irregular manner with the thickness of reaction layer. In particular, the highest shear strength of 62.70 MPa is obtained at oxygen partial pressure of 0.02 atm and SiO 2 content of 1.5 wt%. [ABSTRACT FROM AUTHOR]

Cell fusion is a fundamental biological process that is involved in the development of most eukaryotic organisms. During the fusion process in Saccharomyces cerevisiae , cells respond to pheromones to trigger the MAPK (mitogen-activated protein kinase) cascade to initiate mating, followed by polarization, cell-wall remodeling, membrane fusion, and karyogamy. We highlight the applications of the yeast mating signal pathway in promoter engineering for tuning the expression of output genes, as well as in metabolic engineering for decoupling growth and metabolism, biosensors for sensitive detection and signal amplification, genetic circuits for programmable biological functionalities, and artificial consortia for cell–cell communication. Strategies such as exploiting rational engineering of modular circuits and optimizing the reproductive pathway to precisely maneuver physiological events have implications for scientific research and industrial development. The mating response of yeast gives deep insights that facilitate the application of cell fusion to gene transfer, antibody production, and cell reprogramming. Components of the yeast mating-specific mitogen-activated protein kinase (MAPK) signaling pathway, including scaffolds, G protein-coupled receptors (GPCRs), and pheromone-responsive promoters, constitute a toolbox for the rational design of artificial systems. The yeast mating signal pathway has significant synthetic biology applications, including tuning the outputs by promoter engineering, decoupling growth and metabolism through metabolic engineering, detecting and amplifying signals in biosensors, programming biological functions in circuits, and manipulating cell–cell communication in artificial consortia. Advances in synthetic biology tools such as omics, microfluidics, CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9), and machine learning have significantly boosted cell-fusion studies. [ABSTRACT FROM AUTHOR]

Regeneration serves as a self-protective mechanism that allows a tissue or organ to recover its entire form and function after suffering damage. However, the regenerative capacity varies greatly within the plant kingdom. Primitive plants frequently display an amazing regenerative ability as they have developed a complex system and strategy for long-term survival under extreme stress conditions. The regenerative ability of dicot species is highly variable, but that of monocots often exhibits extreme recalcitrance to tissue replenishment. Recent studies have revealed key factors and signals that affect cell fate during plant regeneration, some of which are conserved among the plant lineage. Among these, several members of the ETHYLENE RESPONSE FACTOR (ERF) transcription factors have been implicated in wound signaling, playing crucial roles in the regenerative mechanisms after different types of wounding. An understanding of plant regeneration may ultimately lead to an increased regenerative potential of recalcitrant species, producing more high-yielding, multi-resistant and environmentally friendly crops and ensuring the long-term development of global agriculture. [ABSTRACT FROM AUTHOR]

Herein, three new fluorostyrylindazoles bearing one, three and five fluorine atoms (FPIZ , TFPIZ and PFPIZ) have been synthesized. Interestingly, the crystal of PFPIZ bent back away from the lighht source at the initial stage of 365 nm light irradiation, and then it showed phototropic bending when prolong the irradiation time without changing the irradiation direction. It was found that the photo-induced [2 + 2] cycloaddition could lead to the expansion and contraction of the unit cell in different directions, and in turn trigger the crystal to exhibit macroscopic mechanical moving. Meanwhile, the photochemical reaction was reasonable for the photochromism of the PFPIZ , which is helpful for the visual observation of the photomechanical effects. For instance, the fluorescence of the crystals of PFPIZ was changed from blue-purple to white under 365 nm irradiation. Besides, TFA (trifluoroacetic acid) could quench the emission of the synthesized fluorostyrylindazoles to different degree in solutions as well as in the films. The acidochromism of the styrylindazole derivatives was originated from the protonation of indazole by acid. The design of multi-stimuli response crystalline materials would be helpful for the fabrication of intelligent photoactuators and fluorescence sensors. [Display omitted] • The molecular crystals based on (E)-1-methyl-3-(2-(perfluorophenyl)vinyl)-1 H -indazole exhibited photomechanical effects. • Stereospecific photo-induced [2 + 2] cycloaddition underwent in the crystal of PFPIZ. • The fluorescence of the crystals of PFPIZ was changed from blue-purple to white on account of the photodimerization. • The films of fluorostyrylindazoles could probe gaseous trifluoroacetic acid rapidly and sensitively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five strains of LAB were associated with improved flavor. • LAB fermentation was associated with increased organic acid and decreased sugars. • Important metabolic compounds of different LAB fermentation were identified. • Specific strains can improve enzyme inhibition and antioxidant activities. • Isoquercitrin and m -coumaric acid content reflected the strain/species specificity. Lactic acid bacteria (LAB) have exhibited strain/species specificity for different food matrices. We investigated the impact of LAB fermentation on the flavor, chemical profile, and bioactivity of goji juice. The colony counts of five selected strains reached above 8.5 log CFU/mL. The fermentation increased the organic acids, decreased the sugars, and improved the sensory quality of goji juice. The majority of the strains had increased acetic acid, heptanoic acid, ethyl phenylacetate, and linalool levels. Specific strains suppressed α-glucosidase and pancreatic lipase activities and increased the antioxidant activities of fermented goji juice. Based on non-targeted metabolomics and activities, 23 important differential metabolites were screened among 453 metabolites. The quantification results showed that isoquercitrin and m -coumaric content varied among strains, reflecting the strain specificity in flavone and flavonol biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis. These findings will provide useful information for fermented goji juice biochemistry research. [ABSTRACT FROM AUTHOR]

Four fluorescent low molecular weight gelators based on benzoxazole or benzothiazole functionalized pyrimidine were designed and synthesized. The ability of the target was tested, and all compounds could form stable supramolecular gels in an alcohol/water mixture and its fluorescence increased during gel formation. Photophysical spectra during gel formation, SEM, XRD, FT-IR study suggested that the self-assembly was driven by hydrogen bonding, van der Waals forces and weak π-π interaction. Interestingly, the gel collapsed after being illuminated by 365 nm UV light and 1H NMR of the gel before and after illumination proved that the [2 + 2]-cycloaddition between the double bond of pyrimidine was responsible for the light response. Furthermore, the fluorescent of xerogel film could be quenched by volatile acids while the fluorescent of the solution was enhanced after acid was added. The different phenomena were discussed. The nano-fiber assembled via gel formation could be used as fluorescent imaging material of latent fingerprints. [Display omitted] • Design and synthesis of novel uracil derivatives containing benzoxazole and benzothiazole. • Benzoxazole-modified uracil derivatives exhibit good gelation abilities and driving force of gel formation was investigated. • The gel could respond to light and acid. The response mechanism was studied. • The nano-materials assembled via gel formation could be used as fluorescent imaging material of latent fingerprints. [ABSTRACT FROM AUTHOR]

Axially wrinkled SnO 2 /TiO 2 heteronanotubes have been successfully prepared by sacrificial template method combined with hydrothermal synthesis. The special folded morphology of SnO 2 /TiO 2 nanostructures may provide more active sites, and the S-scheme heterojunction between SnO 2 and TiO 2 enhances the separation of photogenerated electron-hole pairs, which are conducive to the improvement of photocatalytic degradation for organic pollutants. Using SnO 2 /TiO 2 nanotubes as catalyst, the removal rate of Rhodamine B (RhB), methyl orange (MO) and tetracycline hydrochloride (TCH) under the irradiation of a xenon lamp is 93%, 91% and 85%, respectively. After five cycles, the removal efficiency of organic pollutants maintains almost unchanged, indicating that the synthesized SnO 2 /TiO 2 nanotubes has good stability and reusability. In addition, trapping experiments have been carried out to investigate the major reactive oxidative species for organic pollutants photodegradation. This study provides a facile avenue to design nanotublar photocatalysts with enhanced degradation performance for organic pollutants. [ABSTRACT FROM AUTHOR]

To prepare colorless polyimides (CPIs), two novel diamines, namely 6-amino-2-(2′-methyl-4′-aminobenzene)-N-phenylbenzimidazol (5a) and 6-amino-2-(2′-trifluoromethyl-4′-aminobenzene)-N-phenylbenzimidazol (5b) were synthesized, and two series of polyimides derived from them were developed. Except for the inherent asymmetric structures, the twisted moieties had been successfully incorporated in the benzimidazole dianmines through 2′- and N-substituents. The loose chain packing and hindered charge transfer (CT) interaction caused by the askew and distorted segments provided the polyimides with excellent optical transparency (80% transmittance at 400 nm, semi-alicyclic series), while the resulting films inherited the unique superheat-resistance of poly(benzimidazole imide)s (PBIIs), e.g., high glass-transition temperatures (up to 402 °C). Such outstanding optical and thermal properties expanded their application as heat-resistant colorless materials. Furthermore, the correlation between various 2′-substituents and characters of these PBII films was systematically analyzed. These data indicated that these colorless polyimides had potential application as optical and optoelectronic materials. [Display omitted] • Two novel benzimidazole dianmines containing 2′- and N-substituents (5a and 5b) were successfully synthesized. • Polyimide films with asymmetric and twisted structures were successfully synthesized. • The semi-aromatic poly(benzimidazole imide) films achieved colorlessness (T 400 = 80–81% and T g = 394–402 °C). • The effect of various 2′-substitutions on the properties of these N-phenyl-poly(benzimidazole imide)s was investigated. [ABSTRACT FROM AUTHOR]

Zebrafish Fish-egg lectin (zFEL) has been identified and proved to be a maternal factor with antibacterial and opsonic ability in fishes. In this study, we found that zFEL was capable of enhancing the phagocytosis of the bacteria by macrophages of mouse (RAW264.7 and mouse peritoneal macrophages), suggesting a cross-species function of zFEL in higher animals. Further studies showed that zFEL can active the antigen presentation ability by up-regulating the expression of CD80, CD86 and MHC II. Meanwhile, zFEL also promoted the polarization of macrophages to M1-type, which was confirmed by the increase of cytokines TNF-α and IL-6. The expression of p38 gene was up-regulated in macrophages preincubated with zFEL. Taken together, zFEL appears opsonic function in mammal macrophages and has potential application in immunomodulation. • Cross-species opsonic activity is found by zebrafish fish-egg lectin (zFEL) on mouse macrophages. • zFEL can up-regulate the expression of CD80, CD86 and MHC II on macrophages. • zFEL promotes the polarization of macrophages to M1-type. [ABSTRACT FROM AUTHOR]

Nowadays, there are few studies in vivo to explore the effects of Human Cytomegalovirus (HCMV) single gene such as immediate early protein 2 (IE2) on the nervous system, let alone the mechanism that IE2 causes cognitive impairment. In this study, the Rosa26-LSL-IE2/Cre mouse was used to show the effects of IE2 on the cognitive ability and the GluNRs/CaMKIIα/CREB signaling pathway in the hippocampus. We divided the mice into experimental and control groups based on the results of PCR firstly. After that, the cognitive abilities of the two groups were compared through new object recognition (NOR) and Morris water maze (MWM) tests. The results of the behavioral tests showed that the cognitive ability of the experimental mice was lower than that of the control group. It is known that changes in the expression levels of N-methyl D -aspartate receptor 1, 2A, and 2B (GluN1, GluN2A, GluN2B) affect synaptic plasticity and cause cognitive changes. Finally, we analyzed the expression levels of GluN1, GluN2A, GluN2B, and related signaling pathway molecules by qPCR and western blot. We found that the expression levels of the GluNRs/CaMKIIα/CREB signaling pathway were decreased in the experimental group. These results indicated that IE2 could affect the expression levels of GluNRs/CaMKIIα/CREB signaling pathway, which was closely related to the cognitive impairment of the experimental group. In summary, we used this novel mouse model to show that IE2 could cause cognitive impairment in the hippocampus, which might be related to the GluNRs/CaMKIIα/CREB signaling pathway. It is helpful to further understand the mechanism of the cognitive impairment induced by HCMV IE2. • Human cytomegalovirus IE2 could be stably expressed and inherited in the hippocampus of the Rosa26-LSL-IE2/Cre mice. • HCMV IE2 destroyed the structure of hippocampus in the Rosa26-LSL-IE2/Cre mouse. • HCMV IE2 caused cognitive impairment in the hippocampus. • The cognitive impairment caused by IE2 might through the GluNRs/CaMKIIα/CREB signaling pathway. [ABSTRACT FROM AUTHOR]

Agricultural products are frequently contaminated by mycotoxins; thus, the accurate detection of mycotoxins is important to food safety. Zearalenone (ZEN), a mycotoxin produced by certain Fusarium and Gibberella species, is a group III carcinogen. We developed a universal surface-enhanced Raman scattering (SERS) aptasensor for the detection of ZEN. The SERS biosensor consists of two functional nanomaterials: sulfhydryl (SH)-ZEN aptamer complementary DNA-modified Fe 3 O 4 @Au was used as a capture probe and SH-ZEN aptamer-modified Au@Ag core-shell nanoparticles served as reporter probes. In the absence of ZEN, the highest Raman signal was obtained owing to the SERS effects of Fe 3 O 4 @Au and Au@Ag core-shell nanoparticles. Conversely, the addition of ZEN triggered the release of Au@Ag core-shell nanoparticles from Fe 3 O 4 @Au, leading to a decrease in SERS intensity after magnetic separation. Hybridization of the ZEN aptamer and its complementary strand generated a strong SERS signal from the reporter probe. Moreover, preferential binding of the ZEN aptamer to ZEN was observed. The signal intensity in SERS decreased linearly when the capture probes released the reporter. For ZEN detection, a linear range from 0.005 to 500 ng mL−1, with an R2 of 0.9981, was obtained. The detection limit was 0.001 ng mL−1. The SERS aptasensor showed excellent performance for analytical applications with real-world samples (beer and wine). This study presents a new model for the detection of mycotoxins based on simple changes in aptamers. [Display omitted] • Detection of mycotoxins is important to overcome food contamination. • SERS aptasensor was developed to detect zearalenone, a group III carcinogen. • SH-cDNA-modified Fe 3 O 4 @Au as capture probe; SH-Apt-modified Au@Ag as reporter probe. • Wide linear range of 0.005–500 ng mL−1 for detecting zearalenone. • Novel model for the detection of mycotoxins to guarantee food safety. [ABSTRACT FROM AUTHOR]