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The study aims to investigate the pragmatic information in Chinese-English dictionaries. A general survey was made to examine the status quo of the pragmatic information in the existing Chinese-English dictionaries. It was found that all large- and medium-sized dictionaries under investigation provided some pragmatic information. However, these dictionaries only provided the pragmatic information about the Chinese headword but not the English equivalent. The author argues that since the target users of these dictionaries are Chinese EFL learners, they should state clearly the pragmatic differences between the headword in the source language and the equivalent in the target language. Moreover, the cultural notes provided should be focused on the English equivalents instead.

This study explores the collocational patterns of ten high-frequency adjectives in the Written Corpus of China English (abbreviated to WCCE) with a focus on its collocations with nouns. A corpus-based comparative methodology was adopted to investigate the differences between China English and British English in the use of adjective and noun collocational patterns. The major findings of the study can be stated as follows: 1) Some collocational structures only occur in the Chinese context, such as economic rebalancing, economic belt, and international airspace. 2) Some collocational structures, like economic corridor, economic construction, new energy, are used more frequently in China English than in British English. 3) The frequencies of some collocational structures in BNC are much greater than those in WCCE, in particular, Old Testament, local election. The reasons for these different uses of collocational structures with distinct Chinese features might include (but not limited to), i. the development of China’s economy (e.g. economic belt, economic corridor); ii. the differences between China and Britain in politics and society (e.g. Old Testament, local election); iii. the influence of the development of science (e.g. new energy); iv. linguistic transfer (e.g. old Yao, economic take-off). The findings show that China English has its distinctive collocational patterns which may suggest that English used in China has undergone a process of nativization.

Significant breakthroughs have been made in the development of surface-enhanced Raman scattering (SERS) substrates constructed by depositing plasmonic Ag onto nanostructured platforms. AlOOH is widely fabricated using hydrothermal, microwave, and microemulsion methods. Among these, the high catalytic activity of AlOOH prepared by the microemulsion method is derived from its high specific surface area, more active surface OH groups, and multi-active adsorption sites. And nanomaterials with such excellent properties have not yet been fabricated on a SERS-based platform to improve the Raman-enhanced properties of Ag achieving high-sensitivity detection of probe molecules especially with affinity for OH groups. The precious metal Ag has long been known to serve as traps to capture electrons and holes generated by plasmon resonance, reducing electron-hole recombination and exhibiting high activity in photocatalytic processes. In this work, to demonstrate the SERS substrate activity of the AlOOH@Ag complex, it has been successfully applied to identify congo red (CR) molecules with high sensitivity, methyl blue (MB) and methyl orange (MO), enabling trace-level detection with enhanced performance much stronger than Ag substrate.

Mercuric ion (Hg2+), a poisonous metal ion that remained in water ecosystems, can severely damage the human central and peripheral nervous system and kidneys. Consequently, rapid and highly sensitive methods to determine trace Hg2+ are meaningful to discuss. We have proposed a novel approach of surface-enhanced Raman scattering (SERS) for the quantitative analysis of Hg2+ in water samples using dithizone (DTZ) as a Raman reporter. DTZ-modified silver nanoparticles (AgNPs) produced a strong SERS signal. In the presence of Hg2+, the DTZ can capture Hg2+ composing a stable structure, resulting in DTZ leaving the surface of the AgNPs, with an accompanying decrease in the signal. The proposed SERS assay showed a linear range of 10−4–10−8 M, with a limit of detection of 9.83 × 10−9 M. The sensor has low detection cost, rapid detection speed, and uncomplicated sample pretreatment. Furthermore, this method can be successfully utilized to detect Hg2+rapidly in water samples, which sheds new light on the detection of Hg2+ in the environment.

After vitrectomy, the ideal vitreous substitute should be implanted to maintain the normal function of the eye. However, the existing materials (such as silicone oil, air, perfluorocarbons, etc.) still have some shortcomings and cannot fully meet the clinical needs. In this study, thiolated hyaluronic acid (SH-HA) was prepared based on hyaluronic acid. The SH-HA hydrogel was formed by a simple transformation of the sulfhydryl group to the disulfide bond, which had high transparency, controllable swelling property, suitable mechanical strength, excellent biocompatibility and similar physical and chemical properties to natural vitreous. SH-HA hydrogel was filled into the eyes of experimental rabbits to replace their own vitreous after vitrectomy. During the 90 days follow-up period, SH-HA hydrogel showed excellent intraocular compatibility, maintained normal intraocular pressure (IOP), and no cataract, endophthalmitis, retinal detachment and other complications were observed. In general, SH-HA hydrogel has great potential as a vitreous substitute.

This work presents a theoretical and experimental approach for the coupling of 4-ethynylaniline (4-APA) and 4-ethynylnitrobenzene (4-NPA) in the theoretical application of density functional theory (DFT) and experimental monitoring of surface-enhanced Raman spectroscopy (SERS). The results support electromagnetic enhancement to drive the conversion of aromatic alkynamine and nitro compounds and regulation by the catalytic coupling reaction conditions. In addition, this work investigates the adsorption site effect of surface plasmon coupling reactions of 4-APA and 4-NPA molecules into alkynyl azo compounds. This study presents theoretical and experimental images used to analyze the plasmon-driven surface catalytic reaction system.

Heavy metals have been widely applied in industry, agriculture, and other fields because of their outstanding physics and chemistry properties. However, heavy metal pollution is inevitable in the process of mass production and emission. Heavy metal ions will cause irreversible harm to the human body and other organisms due to their nondegradable nature even at low concentrations of exposure and ingestion. Therefore, it is of great significance for human health and ecological environment to develop high accuracy and sensitivity as well as stable techniques for detecting heavy metal ions. In recent years, surface-enhanced Raman scattering (SERS) spectroscopy has been regarded as a promising new technique for the determination of trace heavy metal ions on account of its special fingerprint identification capability, high sensitivity, rapid detection ability, and simple operation. This review summarized in detail the basic principles and strategies for detecting mercury ions, copper ions, arsenic ions, zinc ions, cadmium ions, lead ions, and chromium (VI) ions as well as the current challenges and future trends for the determination of heavy metal ions based on SERS technology.

Chitosan (CTS) has been used as a nerve guidance conduit (NGC) material for bridging peripheral nerve defects due to its biocompatible, biodegradable, and non-toxic properties. However, the nerve regeneration effect of chitosan alone is restricted due to its inadequate biological activity. Herein, a composite, bioactive chitosan based nerve conduit, consisting of outer warp-knitted tube scaffold made from medical-grade chitosan fiber, and inner porous cross linked carboxymethyl chitosan (C-CM-CTS) sponge with radial texture was developed. The inner wall of the scaffold was coated with C-CM-CTS solution. CM-CTS provided favorable bioactivities in the composite chitosan-based nerve conduit. An in vitro study of CM-CTS revealed its satisfying biocompatibility with fibroblast and its inhibition of oxidative damage to Schwann cells. As the internal filler of the NGC, the lyophilized sponge of C-CM-CTS showed a longitudinal guidance effect for nerve reconstruction. After 10 mm defect in rat sciatic nerve was bridged with the composite bioactive chitosan-based nerve conduit, the nerve conduit was able to effectively promote axonal regeneration and played a positive role in inducing nerve regeneration and functional recovery. In addition to the functional advantages, which are equal to those of an autograft; the technology for the preparation of this conduit can be put into mass production.

Wound healing is a complicated process that influences patient's life quality. Plant-based polysaccharide has recently gained interest in its use in wound dressing materials because of its biological compatibility, natural abundance, and ideal physiochemical properties. The present study reveals the potential of polysaccharide isolated from Moringa oleifera seed (MOS-PS) and its nanocomposite with silver (MOS-PS-AgNPs) as alternative materials for wound dressing. First, MOS-PS was isolated and structurally characterized by TLC, HPLC, FTIR, NMR, and GPC analyses. A green and simple method was used to synthesize AgNPs using MOS-PS as a stabilizing and reducing agent. The size, morphology, and structure of the MOS-PS-AgNPs were characterized by UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and zeta potential analysis. The results showed that the MOS-PS-AgNPs were spherically shaped, having no cytotoxicity toward mouse fibroblasts cells and promoting their in-vitro migration. Moreover, the MOS-PS-AgNPs displayed strong anti-microbial activity against wound infectious pathogenic bacteria. Finally, the MOS-PS-AgNPs were used for dressing animal wounds and its preliminary mechanism was studied by RT-PCR and histological analysis. The results showed that the MOS-PS-AgNPs can promote wound contraction and internal tissue growth well. Overall, our results indicated that the MOS-PS-AgNPs might be an excellent candidate for use as an optimal wound dressing material.

Porous aromatic framework materials with high stability, sensitivity, and selectivity have great potential to provide new sensors for optoelectronic/fluorescent probe devices. In this work, a luminescent porous aromatic framework material (LNU-23) was synthesized via the palladium-catalyzed Suzuki cross-coupling reaction of tetrabromopyrene and 1,2-bisphenyldiborate pinacol ester. The resulting PAF solid exhibited strong fluorescence emission with a quantum yield of 18.31%, showing excellent light and heat stability. Because the lowest unoccupied molecular orbital (LUMO) of LNU-23 was higher than that of the nitro compounds, there was an energy transfer from the excited LNU-23 to the analyte, leading to the selective fluorescence quenching with a limit of detection (LOD) ≈ 1.47 × 10−5 M. After integrating the luminescent PAF powder on the paper by a simple dipping method, the indicator papers revealed a fast fluorescence response to gaseous nitrobenzene within 10 s, which shows great potential in outdoor fluorescence detection of nitro compounds.

The strong radioactivity of iodine compounds derived from nuclear power plant wastes has motivated the development of highly efficient adsorbents. Porous aromatic frameworks (PAFs) have attracted much attention due to their low density and diverse structure. In this work, an azo group containing PAF solid, denoted as LNU-58, was prepared through Suzuki polymerization of tris-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-phenyl)-amine and 3,5-dibromoazobenzene building monomers. Based on the specific polarity properities of the azo groups, the electron-rich aromatic fragments in the hierarchical architecture efficiently capture iodine molecules with an adsorption capacity of 3533.11 mg g−1 (353 wt%) for gaseous iodine and 903.6 mg g−1 (90 wt%) for dissolved iodine. The iodine uptake per specific surface area up to 8.55 wt% m−2 g−1 achieves the highest level among all porous adsorbents. This work illustrates the successful preparation of a new type of porous adsorbent that is expected to be applied in the field of practical iodine adsorption.

Lipid metabolism in bovine mammary epithelial cells has been the primary focus of the research of milk fat percentage of dairy cattle. Functional microRNAs can affect lipid metabolism by regulating the expression of candidate genes. The purpose of the study was to screen and identify differentially expressed miRNAs, candidate genes, and co-regulatory pathways related to the metabolism of milk fat. To achieve this aim, we used miRNA and transcriptome data from the mammary epithelial cells of dairy cattle with high (H, 4.85%) and low milk fat percentages (L, 3.41%) during mid-lactation. One hundred ninety differentially expressed genes and 33 differentially expressed miRNAs were significantly enriched in related regulatory networks, of which 27 candidate genes regulated by 18 differentially expressed miRNAs significantly enriched in pathways related to lipid metabolism (p

Herein, we developed a concise, time-efficient, and high selective assay for detecting Fe2+ through its triggered surface plasmon-catalyzed reduction reaction of p-nitrothiophenol (PNTP) to p,p′-dimercaptoazobenzene (DMAB) based on surface-enhanced Raman scattering (SERS) spectroscopy. When Fe2+ was added to the PNTP-AuNPs system, the appearance of three characteristic peaks at 1142, 1392, and 1140 cm− 1 attributed to DMAB demonstrated that Fe2+ induced the catalytic coupling reaction of PNTP. The Raman intensity ratio of the peak at 1142 cm− 1 to the peak at 1336 cm− 1 and the concentration of Fe2+ presented a good linear response from 10 to 100 µM with a limit of detection (LOD) of 0.35 µM. Besides, the probable reaction process has been put forward. More importantly, the entire detection process can be completed within 2 min and was used successfully for the detection of Fe2+ in river water.

A new type of catalyst was synthesized by immobilizing heteropolyacid on ionic liquid-modified mesostructured cellular silica foam (denoted as MCF) and applied to the oxidative desulfurization of fuel. The surface morphology and structure of the catalyst were characterized by XRD, TEM, N2 adsorption–desorption, FT-IR, EDS and XPS analysis. The catalyst exhibited good stability and desulfurization for various sulfur-containing compounds in oxidative desulfurization. Heteropolyacid ionic liquid-based MCF solved the shortage of the amount of ionic liquid and difficult separation in the process of oxidative desulfurization. Meanwhile, MCF had a special three-dimensional structure that was not only highly conducive to mass transfer but also greatly increased catalytic active sites and significantly improved catalytic efficiency. Accordingly, the prepared catalyst of 1-butyl-3-methyl imidazolium phosphomolybdic acid-based MCF (denoted as [BMIM]3PMo12O40-based MCF) exhibited high desulfurization activity in an oxidative desulfurization system. The removal of dibenzothiophene could achieve levels of 100% in 90 min. Additionally, four sulfur-containing compounds could be removed completely under mild conditions. Due to the stability of the structure, sulfur removal efficiency still reached 99.8% after the catalyst was recycled six times.

The traditional electrochemical deposition process used to prepare Cu(In, Ga)Se2 (CIGS) thin films has inherent flaws, such as the tendency to produce low-conductivity Ga2O3 phase and internal defects. In this article, CIGS thin films were prepared under vacuum (3 kPa), and the mechanism of vacuum electrodeposition CIGS was illustrated. The route of Ga incorporation into the thin films could be controlled in a vacuum environment via inhibiting pH changes at the cathode region. Through the incorporation of a low-conductivity secondary phase, Ga2O3 was inhibited at 3 kPa, as shown by Raman and X-ray photoelectron spectroscopy. The preparation process used a higher current density and a lower diffusion impedance and charge transfer impedance. The films that were produced had larger particle sizes.

The separation and transfer of photogenerated electron–hole pairs in semiconductors is the key point for photoelectrochemical (PEC) water splitting. Here, an ideal TaON/BiVO4 heterojunction electrode was fabricated via a simple hydrothermal method. As BiVO4 and TaON were in well contact with each other, high performance TaON/BiVO4 heterojunction photoanodes were constructed. The photocurrent of the 2-TaON/BiVO4 electrode reached 2.6 mA cm−2 at 1.23 V vs. RHE, which is 1.75 times as that of the bare BiVO4. TaON improves the PEC performance by simultaneously promoting the photo-generated charge separation and surface reaction transfer. When a Co-Pi co-catalyst was integrated onto the surface of the 2-TaON/BiVO4 electrode, the surface water oxidation kinetics further improved, and a highly efficient photocurrent density of 3.6 mA cm−2 was achieved at 1.23 V vs. RHE. The largest half-cell solar energy conversion efficiency for Co-Pi/TaON/BiVO4 was 1.19% at 0.69 V vs. RHE, corresponding to 6 times that of bare BiVO4 (0.19% at 0.95 V vs. RHE). This study provides an available strategy to develop photoelectrochemical water splitting of BiVO4-based photoanodes.

Ultramicropores (size < 0.7 nm) are critically demanded to provide an efficient path for the penetration and transportation of electrolytes to achieve high-performance supercapacitors. Here, a self-sacrificial template approach is adopted, which introduces C8 alkyl chains with a kinetic diameter of 0.8-1 nm to occupy the cavity of a porous aromatic framework (PAF). During the heating process, the alkyl chains decompose from the dense architecture as the temperature increased from 500 to 600 °C, forming ∼1 nm micropores. The newly-obtained cavities provide sites for thermal-driven skeleton engineering (700-900 °C) to obtain ultramicropores. Based on the well-defined pore structure, the carbonized PAF solid revealed outstanding electrochemical performances, including high rate and long-term stability in a 6 M KOH electrolyte. Notably, the specific capacitance (294 F g-1) derived from the self-sacrificial template method exceeds the capability of all the other methods for the construction of ultramicropores including self-template strategy, carbonization of nanoparticles, and template-assisted strategy. The synthesis of ultramicroporous carbons via the self-sacrificial template route opens up a promising gate to adjust the porous structure for high-performance applications in supercapacitors.

Plasmon-assisted reactions have different reaction mechanisms than conventional chemical reactions occurring in solutions, and the hot electrons produced by plasmon decay play an irreplaceable role...

microRNA is a class of single-stranded RNA molecules of about 22-24 nucleotides in length, which regulate a variety of biological processes, including lipid metabolism and triglyceride synthesis at transcriptional and translational levels by degrading target mRNAs or interfering with the protein production. In this study, the effect of miR-2382-5p on triglyceride levels was examined in bovine mammary epithelial cells (BMECs), and the results showed that miR-2382-5p could decrease the content of triglyceride. Furthermore, miR-2382-5p regulated the expression of lipoprotein lipase (LPL), peroxisome proliferator-activated receptor gamma co-activator 1beta (PPARGC1B), hormone-sensitive lipase (HSL), and peroxisome proliferator-activated receptor gamma (PPARγ), which are known to increase triglyceride decomposition in lipid metabolism. Luciferase reporter assay and quantitative real-time PCR (qPCR) validated that miR-2382-5p downregulated the mRNA expression of target gene N-myc downstream-regulated gene 2 (NDRG2) by specifically recognizing and binding to its 3'-untranslated region (UTR). Meanwhile, overexpression of NDRG2 led to increased triglyceride and cholesterol production in BMECs. In summary, this study suggested that miR-2382-5p regulated lipid metabolism by targeting NDRG2, which might be a potential target for molecular manipulation of milk fat composition to produce healthy milk. This study also provided basic data for further understanding lipid metabolism in dairy cattle.

Thiram is used as a fungicide and insecticide in agriculture to prevent white rot and anthracnose, but it also produces certain pesticide residues that endanger human health. Polydopamine (PDA) is an adhesive polymer that functionalizes almost all chemical materials, having been inspired by the adhesive properties of catechol and amines in mussel adhesive protein. In this work, we have fabricated a highly sensitive face mask (FM)-based surface-enhanced Raman scattering (SERS) substrate by depositing silver nanoparticles (AgNPs), using a PDA layer as an interface to promote adhesion. Face masks are currently ubiquitous, and are simple and easy to obtain, and this approach can be regarded as waste utilization. FM/PDA/AgNPs can detect Nile Blue A (NBA) probe molecules at concentrations as low as 1.0 × 10− 9 M, and permit measurements with sensitivity and uniformity. The Raman substrate can be used to swab the surface of fruit to detect thiram at concentrations as low as 1.0 × 10− 7 M, and the reproducibility has been assessed. The simple utilization of this flexible SERS substrate holds promise for its practical application in the field of pesticide control.

Gold nanoparticles have received widespread attention as surface-enhanced Raman scattering (SERS) detection active substrates. In this work, we used the nematic liquid crystal molecule N-(4-methoxybenzylidene)-4-butylaniline (MBBA) at room temperature to synthesize liquid crystal (LC)-Au nanoparticles in one step without adding any other reducing agents or stabilizers. Gold nanoparticles synthesized by this method have good sensitivity and stability as a SERS substrate. The nanoparticles can detect Rhodamine 6G (R6G) molecules with a concentration as low as 10−8 M, and the SERS signal does not decrease significantly in 30 days. Using this synthesis principle, we grew gold nanoparticles in a capillary in one step. We expect the proposed method to result in a highly efficient and portable SERS substrate after subsequent improvements.

In this study, zinc aluminum layered double hydroxide (ZnAl-LDH) with a Zn/Al molar ratio 8/1 was synthesized via a facile urea method, and the mixed metal oxide (MMO) was prepared using the corresponding LDH as a precursor. In order to improve the performance of electron transport layer, we introduced graphene into ZnAl-MMO to prepare new nanocomposites, ZnAl-MMO/graphene, as promising photoanodes for dye-sensitized solar cell (DSSC). The bare ZnAl-MMO and formed ZnAl-MMO/graphene nanocomposites were characterized by X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM) and UV–vis absorption spectrum, confirming the presence of graphene and the wurtzite type phase of ZnO. A series of DSSC were fabricated by the corresponding nanocomposites and a D205 as dye. The photovoltaic behavior of these cells based on different graphene concentration was further investigated by electrochemical method. It turned out that the introduced graphene facilitated the dye adsorption and light-scattering, which heightened the performance of DSSC. The DSSC based on ZnAl-MMO/0.2 wt.% graphene reached the best power conversion efficiency (PCE) of 0.51%, showing a rise of 25% approximately when compared with plain ZnAl-MMO.

4,4’-Dithiobisbenzoic acid (DTBA) is equivalent to two 4-mercaptobenzoic acid (pMBA) molecules connected together after losing H+, and this bimolecular mechanism of DTBA efficiently promotes the ionization reaction. Under the irradiation of laser light, DTBA molecules are broken to form bimolecules similar to pMBA, and this kind of bimolecular coupling greatly increases the probability of binding with Ag NPs. Also, this molecule has the carboxylic acid group, which leads to a certain sensitivity to pH. In this article, through the comparison of DTBA and pMBA parallel experiments, it is clear that DTBA has better Raman activity, higher reaction efficiency, and more stable reaction than pMBA. The occurrence of this highly efficient ionization reaction under the monitoring of surface-enhanced Raman spectroscopy (SERS) provides a certain value for the progress of further related reactions, and it also has a wide range of applications in pH sensors and intracellular pH monitoring.

This article reviews mushrooms with anti-breast cancer activity. The mushrooms covered which are better known include the following: button mushroom Agaricus bisporus, Brazilian mushroom Agaricus blazei, Amauroderma rugosum, stout camphor fungus Antrodia camphorata, Jew’s ear (black) fungus or black wood ear fungus Auricularia auricula–judae, reishi mushroom or Lingzhi Ganoderma lucidum, Ganoderma sinense, maitake mushroom or sheep’s head mushroom Grifola frondosa, lion’s mane mushroom or monkey head mushroom Hericium erinaceum, brown beech mushroom Hypsizigus marmoreus, sulfur polypore mushroom Laetiporus sulphureus, Lentinula edodes (shiitake mushroom), Phellinus linteus (Japanese “meshimakobu,” Chinese “song gen,” Korean “sanghwang,” American “black hoof mushroom”), abalone mushroom Pleurotus abalonus, king oyster mushroom Pleurotus eryngii, oyster mushroom Pleurotus ostreatus, tuckahoe or Fu Ling Poria cocos, and split gill mushroom Schizophyllum commune. Antineoplastic effectiveness in human clinical trials and mechanism of anticancer action have been reported for Antrodia camphorata, Cordyceps sinensis, Coriolus versicolor, Ganoderma lucidum, Grifola frondosa, and Lentinula edodes.

The Ag+ is first adopted to oxidize PATP to DMAB. It could act as a SERS substrate and overcomes the drawbacks of the traditional metal sol. Compared with the traditional silver sol system, the intensity of the Raman peak is increased by 10 times.

Hybrid knife as a multi-function endoscopic instrument provides an effective model for endoscopic diagnosis and treatment of diseases. Hybrid knife does not need exchange of instrument during endoscopic operation. It can effectively reduce the potential risk of perforation and hemorrhage so that improving quality of life for patients. The technology has been widely used in clinic, especially in the treatment of digestive internal medicine, and in the course of respiratory intervention. Researchers have started to use the hybrid knife technique and have obtained good surgical results. In this review, we introduced the advantages of hybrid knife and summarized the clinic application, including the tumor excision and the tissue collection for pathology. Furthermore, the application of hybrid knife has significant implication to gastrointestinal and urinary diseases, and airway tumors, and we also explored the possibility of application of hybrid knife system in more diseases. Hybrid knife system has important clinical significance and is worth further study and exploration.

A highly stable electrochemical biosensor for pesticide detection was developed. For the first time polymeric ionic liquids (PILs) were introduced to construct an acetylcholinesterase (AChE) biosensor . AChE was entrapped in PILs microspheres through an emulsion polymerization reaction, where negatively charged Au nanoparticles (Au NPs) can be immobilized by the positively charged PILs, leading to improved catalytic performance. The results suggest that the positively charged PILs not only provide a biocompatible microenvironment around the enzyme molecule, stabilizing its biological activity and preventing its leakage, but also act as a modifiable interface allowing other components with electron transport properties to be loaded onto the polymer substrate, thus providing an efficient electron transport channel for the entrapped enzyme. More notably, when AChE was immobilized in a positively charged environment, the active site is closer to the electrode, promoting faster electron transfer. The detection limits of the constructed electrochemical biosensor AChE@PILs@Au NPs/GCE toward carbaryl and dichlorvos (DDVP) were 5.0 × 10

Multiple-twinned silver nanoparticles (Ag-NPs) supported on mesoporous graphene were prepared through a facile oxidative etching process. Firstly, the Ag-NPs are supported onto the traditional graphene (Ag-NPs/G) by the typical wetness impregnation method. Then, the mesopores with sizes ranging from 5 to 10 nm were successfully fabricated on the initial graphene support through the oxidative etching process assisted by the Ag-NPs. And the Ag-NPs with multiple-twinned structure were simultaneously generated on the mesoporous graphene (Ag-MtNPs/MpG) during the etching process. The synergistic effect of both the unique mesopores on the graphene and the as-prepared multiple-twinned Ag-NPs in the Ag-MtNPs/MpG sample dramatically enhanced the release rate of silver ions (Ag+) and resulted in robust antibacterial activity of against Escherichia coli, in comparison with that of single crystallized Ag-NPs supported on traditional graphene (Ag-NPs/G). The present method paves a feasible way to design novel Ag based antibacterial materials.

Carbon dots (CDs) are known as the rising star of carbon-based nanomaterials and, by virtue of their unique structure and fascinating properties, they have attracted considerable interest in different fields such as biological sensing, drug delivery, photodynamic therapy, photocatalysis, and solar cells in recent years. Particularly, the outstanding electronic and optical properties of the CDs have attracted increasing attention in biomedical and photocatalytic applications owing to their low toxicity, biocompatibility, excellent photostability, tunable fluorescence, outstanding efficient up-converted photoluminescence behavior, and photo-induced electron transfer ability. This article reviews recent progress on the synthesis routes and optical properties of CDs as well as biomedical and photocatalytic applications. Furthermore, we discuss an outlook on future and potential development of the CDs based biosensor, biological dye, biological vehicle, and photocatalysts in this booming research field.

Porous carbon nanofibers with unique hierarchical structures have great potential in many fields, including heterogeneous catalysis, optoelectronics, and sensing. However, several preparation issues, such as additional templates, complicated processes, and harsh conditions, seriously hamper their widespread use. Here, we control the Sonogashira coupling reaction of linear building monomers─1,4-dibromaphthalene and 1,4-ethylbenzene─at the molecular level. Due to the occurrence of branching chain reaction (side reaction), 1D oligomer expands the growth orientation in the plane direction, forming a curled 1D fiber polymer. After thermal-driven skeleton engineering, porous carbon nanofibers were obtained with hierarchical channels of macro- (150 nm), meso- (5.2 nm), and microcavities (0.5 and 1.3 nm). The integration of macro-/meso-/microporous structure reveals a fast and sufficient interaction with electrolyte molecules, facilitating the construction of high-performance electrical devices. Our strategy, using a side reaction to achieve the dimensionality control of 1D copolymerization, paves a new way for the facile preparation of porous carbon nanofibers.

Eating vegetables with pesticide residues over a long period of time causes serious adverse effects on the human body, such as acute poisoning, chronic poisoning, and endocrine system interference. To achieve the goal of a healthy society, it is an urgent issue to find a simple and effective method to detect organic pesticides. In this work, two fluorescent porous organic polymers, LNU-45 and LNU-47 (abbreviation for Liaoning University), were prepared using π-conjugated dibromopyrene monomer and boronic acid compounds as building units through a Suzuki coupling reaction. Due to the large π-electron delocalization effect, the resulting polymers revealed enhanced fluorescence performance. Significantly, in sharp contrast with the planar π-conjugated polymer framework (LNU-47), the distorted conjugated structure (LNU-45) shows a higher specific surface area and provides a broad interface for analyte interaction, which is helpful to achieve rapid response and detection sensitivity. LNU-45 exhibits strong fluorescence emission at 469 nm after excitation at 365 nm in THF solution, providing strong evidence for its suitability as a luminescent chemosensor for organic pesticides. The fluorescence quenching coefficients of LNU-45 for trifluralin and dicloran were 5710 and 12,000 (LNU-47 sample by ca. 1.98 and 3.38 times), respectively. Therefore, LNU-45 serves as an effective “real-time” sensor for the detection of trifluralin and dicloran with high sensitivity and selectivity.

Simple Summary MicroRNAs are small molecules that can regulate the relative abundance of their target genes by binding to the 3′ untranslated region of the target genes at the post-transcriptional level to affect various biological processes, such as biosynthesis, fat metabolism and proliferation, apoptosis, and cell differentiation. Fertility is one of the most important economic traits in livestock production. Bulls require the continuous production of high-quality spermatozoa in abundance. The quality of semen is an exceptionally important factor affecting the fertilization rate of the dairy cow and is also associated with the increasing conception rate in the process of artificial insemination. Therefore, accurately predicting fertility potential for a semen sample from donor bull for artificial insemination is crucial for consistently high reproductive efficiency. The present study performed a genome-wide sequencing analysis of microRNAs and mRNAs between immature and mature testes of Chinese Red Steppes. These results provide novel candidate microRNAs and functional genes related to bull reproduction traits and the networks between microRNAs and target genes, which will provide a useful genetic mechanism and epigenetic information for marker-assisted selection of bulls with excellent sperm quality in the future. Abstract This study aims to screen potential regulators and regulate fecundity networks between microRNAs (miRNAs) and target genes. The bovine testes of immature and mature Chinese Red Steppes were performed by genome-wide analysis of mRNAs and miRNAs. Compared with testicular tissues of newborns, 6051 upregulated genes and 7104 downregulated genes in adult cattle were identified as differentially expressed genes (DEGs). The DEGs were significantly enriched in 808 GO terms (p < 0.05) including male gonad development, male genitalia development, spermatogenesis, and sperm motility. Moreover, DEGs were also significantly enriched in 105 KEGG pathways (p < 0.05), including cGMP-PKG signaling pathway and calcium signaling pathway. To explore the expression of miRNA-regulated gene expression, 896 differentially expressed target genes negatively regulated with the expression levels of 31 differentially expressed miRNAs (DERs) were predicted and analyzed, and a network-integrated analysis was constructed. Furthermore, real-time PCR was performed to verify the expression levels of DEGs and DERs. Our results identified novel candidate DEGs and DERs correlated with male reproduction and intricate regulating networks between miRNAs and genes, which will be valuable for future genetic and epigenetic studies of sperm development and maturity, as well as providing valuable insights into the molecular mechanisms of male fertility and spermatogenesis in cattle.

An ionic liquid (IL)-based liposome was utilized as a substrate to construct a SERS platform. The isotropy of the IL outer surface together with its ion-exchange property led to the array-like growth of Au nanoparticles (NPs), generating hot-spots and resulting in anionic probes being present on the hot-spot regions. The simultaneous strategy of enrichment and localization endowed the platform with ability to detect trace amounts of anionic probes.

The purpose of this study was to develop a flexible substrate methylcellulose-decorated silver nanoparticles (MC/Ag NPs) film and explore its application in fruits and vegetables by surface enhanced Raman spectroscopy (SERS) technology for rapid detection of pesticides. The performance of the MC/Ag NPs film substrate was characterized by Nile blue A (NBA), and the detection limit was as low as 10−8 M. The substrate also exhibited satisfactory Raman signal strength after two months of storage. The impressive sensitivity and stability were due to the excellent homogeneity of the silver nanoparticles that were grown in situ in the methylcellulose matrix, which generated “hot spots” between the silver nanoparticles without a large amount of aggregation, and resulted in the ultra-high sensitivity and excellent stability of the MC/Ag NPs film substrate. The MC/Ag NPs film substrate was used to detect thiram pesticides on tomato and cucumber peels, and the minimum detectable level of thiram was 2.4 ng/cm2, which was much lower than the maximum residue level. These results indicate that the MC/Ag NPs film is sensitive to rapid detection of multiple pesticides in food.

Simple Summary Fertility is one of the essential reproduction traits of bulls, and accurate prediction of fertility potential using a semen sample from a donor bull for artificial insemination is crucial to achieve consistently high reproductive efficiency. Somatic cells, such as Sertoli cells and Leydig cells, are important in testis formation and provide a nurturing and regulatory environment for spermatogenesis. Furthermore, it was suggested that non-coding RNAs, such as microRNAs, long non-coding RNAs, circular RNAs, and Piwi-interacting RNA, function as important regulators of gene expression at post-transcriptional level in spermatogenesis. In this study, microRNA-34c was verified to specifically regulate the AXL gene by targeting a sequence in the 3’ UTR; miRNA-34c can also influence the proliferation, apoptosis, and relative abundance of the transcript of male-reproduction-related genes. Therefore, microRNA-34c can be considered an essential regulator in the process of bull spermatogenesis. These results identify a key microRNA and functional genes in the process of cattle male reproduction, providing useful information for future marker-assisted selection of bulls with excellent sperm quality. Abstract MicroRNAs (miRNAs) play significant roles in mammalian spermatogenesis. Sertoli cells can provide a stable microenvironment and nutritional factors for germ cells, thus playing a vital role in spermatogenesis. However, few studies elucidate the regulation of bovine testicular Sertoli cells by miRNAs. Here, we have reported that miRNA-34c (miR-34c) regulates proliferation, apoptosis, and relative transcripts abundance gene in bovine Sertoli cells. In bovine Sertoli cells, overexpression of miR-34c inhibited proliferation and relative abundance of gene transcripts while promoting apoptosis of Sertoli cells, and the effects were the opposite when miR-34c was knocked down. Receptor tyrosine kinase (AXL) was identified as a direct target gene of miR-34c in Sertoli cells, validated by analysis of the relative abundance of AXL transcript and dual-luciferase reporter assay. The relative abundance of the transcript of genes related to male reproduction in Sertoli cells was changed after the AXL gene was overexpressed, as demonstrated by the RT2 Profiler PCR Array results. In summary, miR-34c specifically regulated the AXL gene by targeting a sequence in the 3′-UTR, which could influence proliferation, apoptosis, and relative abundance of the transcript of male reproduction-related genes. Therefore, miR-34c could be considered an essential regulator in the process of bull spermatogenesis.