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Metal nanohole arrays show excellent performance when applied for sensing, optical fibers, and surface-enhanced spectroscopy, but they are not ideal candidates for surface-enhanced coherent anti-Stokes Raman scattering (SECARS) because of their low enhancement factor (EF). Here, the finite element method was used to study the dependence of the period, width, and thickness of nanoslits on the EF of SECARS and optical transmission in Au nanohole-slit arrays. Nanoslits across the nanoholes significantly modulated the SECARS signal, and we observed an ∼10

SARS-CoV-2, especially the variant strains, is rapidly spreading around the world. Rapid detection methods for the virus are crucial for controlling the COVID-19 epidemic. Herein, a localized surface plasmonic resonance (LSPR) biosensor based on Ω-shaped fiber optic (Ω-FO) was developed for dual assays of SARS-CoV-2 monitoring. Due to its strong ability to control the orientation and density, a new T-shaped aptamer exhibits enhanced binding affinity toward N proteins. After being combined on the fiber optic surface, the T-shaped aptamer sensitively captured N proteins of SARS-CoV-2 for a direct assay. Further, core-shell structured gold/silver nanoparticles functionalized with a T-shaped aptamer (apt-Ag@AuNPs) can amplify the signal of N protein detection for a sandwich assay. The real-time analytical feature of the dual assays endows time-dependent sensitivity enhancement behavior, which provides a guideline to save analytical time. With those characteristics, the LSPR biosensor has been successfully used to rapidly identify 39 healthy volunteers and 39 COVID-19 patients infected with the ancestral or variant SARS-CoV-2. With the help of simple pretreatment, we obtain a true negative rate of 100% and a true positive rate of 92.3% with a short analysis time of 45 min using the direct assay. Further, the LSPR biosensor could also broaden the detection application range to the surface of cold-chain foods using a sandwich assay. Thus, the LSPR biosensor based on Ω-FO was demonstrated to have broad application potential to detect SARS-CoV-2 rapidly.

The wide application of superhydrophobic materials is mainly hindered by the poor mechanical robustness and complicated preparation method. To overcome these problems, we tried to make a combination of hierarchical and self-similar structure by the means of a simple spraying method. By adding nanofiller (carbon nanotube) and microfiller (graphite powder and expanded graphite), the hierarchical structure was constructed. By further doping the fillers in the commercial asphalt uniformly, the self-similar structure was prepared. Based on the aforementioned work, the as-prepared sample could withstand the sandpaper abrasion for 12.00 m under 4.90 kPa. Moreover, this superhydrophobic coating demonstrated good conductivity, superior self-cleaning property, and excellent corrosion resistance. The integration of conductivity with the superhydrophobicity might open new avenues for ground grid applications.

Background Integrins play a prominent role in osteogenic differentiation by transmitting both mechanical and chemical signals. Integrin expression is closely associated with tensile stress, which has a positive effect on osteogenic differentiation. We investigated the relationship between integrin αVβ3 and tensile stress. Methods Human fibroblasts were treated with c (RGDyk) and lentivirus transduction to inhibit function of integrin αVβ3. Y-15, cytochalasin D and verteporfin were used to inhibit phosphorylation of FAK, polymerization of microfilament and function of nuclear YAP, respectively. Fibroblasts were exposed to a cyclic tensile stress of 10% at 0.5 Hz, once a day for 2 h each application. Fibroblasts were harvested on day 4 and 7 post-treatment. The expression of ALP, RUNX2, integrin αVβ3, β-actin, talin-1, FAK, vinculin, and nuclear YAP was detected by Western blot or qRT-PCR. The expression and distribution of integrin αVβ3, vinculin, microfilament and nuclear YAP. Results Cyclic tensile stress was found to promote expression of ALP and RUNX2. Inhibition of integrin αVβ3 activation downregulated the rearrangement of microfilament and the expression of ALP, RUNX2 and nuclear YAP. When the polymerization of microfilament was inhibited the expression of ALP, RUNX2 and nuclear YAP were decreased. The phosphorylation of FAK induced by cyclic tensile stress reduced by the inhibition of integrin αVβ3. The expression of ALP and RUNX2 was decreased by inhibition of phosphorylation of FAK and inhibition of nuclear YAP. Conclusions Cyclic tensile stress promotes osteogenesis of human fibroblasts via integrin αVβ3-microfilament axis. Phosphorylation of FAK and nuclear YAP participates in this process.

Inadequate sensitivity and side-effect are the main challenges to develop cytosensors combining with therapeutic potential simultaneously for cancer diagnosis and treatment. Herein, localized surface plasma resonance (LSPR) based on hybridized nanolayer modified Ω-shaped fiber-optic (HN/Ω-FO) was developed to integrate cytosensor and plasmonic photothermal treatment (PPT). On one hand, hybridized nanolayers improve the coverage of nanoparticles and refractive index sensitivity (RIS). Moreover, the hybridized nanoploymers of gold nanorods/gold nanoparticles (AuNRs/AuNPs) also result in intense enhancement in electronic field intensity (I). On the other hand, Ω-shaped fiber-optic (Ω-FO) led to strong bending loss in its bending part. To be specific, a majority of light escaped from fiber will interact with HN. Thus, HN/Ω-FO synergistically enhances the plasmonic, which achieved the goal of ultrasensitive cytosensor and highly-efficient plasmonic photothermal treatment (PPT). The proposed cytosensor exhibits ultrasensitivity for detection of cancer cells with a low limit of detection down to 2.6 cells/mL was realized just in 30 min. HN/Ω–FO–based LSPR exhibits unique characteristics of highly efficient, localized, and geometry-dependent heat distribution, which makes it suitable for PPT to only kill the cancer cells specifically on the surface or surrounding fiber-optic (FO) surface. Thus, HN/Ω-FO provides a new approach to couple cytosensor with PPT, indicating its great potential in clinical diagnosis and treatment.

In this work, the aluminum conductors containing different trace elements have been prepared. And the influence of the trace elements on the microstructures and properties of aluminum conductor has been examined. It is found that the higher content of Fe and Si as well as higher Fe/Si ratio is helpful for improving the hardness, but it is harmful for the electrical conductivity. The boron addition can make Ti and V transform into borides. Ti element tend to react with B to form TiB2 particles, but when there is both Ti and V, (V, Ti)B2 prefers to be formed. Although borides can be the nucleate substrate for a-Al and refine the grain size of the as-cast Al, the grain size of aluminum conductor containing higher Ti and V is not always the smaller, which is due to the agglomeration and settling down of the borides during the holding. Keywords: Aluminum conductors, Trace elements, Electrical conductivity, Hardness

Background The physical factors of the extracellular matrix have a profound influence on the differentiation behavior of mesenchymal stem cells. In this study, the effect of the biophysical microenvironment on rat bone marrow mesenchymal stem cell (BMSC) osteogenesis was studied both in vitro and in vivo. Methods To prepare cell culture scaffolds of varying stiffness, increasing amounts of hydroxyapatite (HAp) were mixed into a polyethylene glycol/silk fibroin (PEG/SF) solution. The amount of HAp ranged from 25 to 100 mg, which provided for different ratios between HAp and the PEG/SF composite. In vitro, the effect of stiffness on the osteogenic differentiation of rat BMSCs was studied. The outcome measures, which were verified in vivo, included the protein expression of runt-related transcription factor 2 and osteocalcin, alkaline phosphatase activity, and the mRNA expression of osteogenesis-related markers. Results Increasing amounts of HAp resulted in an increased elastic modulus of the cell culture scaffolds. The PEG/SF/HAp fabricated with HAp (50 mg) significantly increased cell adhesion and viability (p p Conclusions We developed a novel cell culture scaffold and demonstrated that substrate stiffness influenced the osteogenic differentiation of rat BMSCs.

An Aflatoxin B1 (AFB1) biosensor was fabricated via an Ag nanoparticles assembly on the surface of a porous anodized aluminum (PAA) membrane. First, the Raman reporter 4-Aminothiophenol (4-ATP) and DNA (partially complementary to AFB1 aptamer) were attached to the surface of Ag nanoparticles (AgNPs) by chemical bonding to form a 4-ATP-AgNPs-DNA complex. Similarly, the surface of a PAA membrane was functionalized with an AFB1 aptamer. Then, the PAA surface was functionalized with 4-ATP-AgNPs-DNA through base complementary pairing to form AgNPs-PAA sensor with a strong Raman signal. When AFB1 was added, AgNPs would be detached from the PAA surface because of the specific binding between AFB1 and the aptamer, resulting in a reduction in Raman signals. The detection limit of the proposed biosensor is 0.009 ng/mL in actual walnut and the linear range is 0.01&ndash, 10 ng/mL. The sensor has good selectivity and repeatability, it can be applied to the rapid qualitative and quantitative detection of AFB1.

Additional file 17: Table S1. Young’s modulus of the scaffolds with different concentration of hydroxyapatite (HAp).

The Cu-TiC composites with non-stoichiometric TiC have been tried to prepare by melt reaction method in this work. It is confirmed that the TiC with different stoichiometries can be successfully prepared by changing the Ti/C ratio in raw material. When there is much excessive Ti in Cu melts, sub-stoichiometric TiC, such as TiC0.6, will be synthesized. However, the sub-stoichiometric TiCx, is not formed by direct reaction between Ti and graphite. In Cu-TiC composites prepared by melt reaction method, near stoichiometric TiCy prefer to be firstly synthesized by reaction between Ti and graphite. Then near stoichiometric TiCy will further react with Ti in the melts to form sub-stoichiometric TiCx (x

In this work, Cu-TiC composites have been successfully prepared by reaction of soluble Ti and carbon coating TiC. Firstly, the ball milling of graphite and TiC mixtures is used to obtain the carbon coating TiC which has fine size and improved reaction activity. After adding the ball milled carbon coating TiC into Cu–Ti melts, the soluble Ti will easily react with the carbon coating to form TiC. This process will also improve the wettability between Cu melts and TiC core. As a result, besides the TiC prepared by reaction of soluble Ti and carbon coating, the ball milled TiC will also be brought into the melts. Some of these ball-milled TiC particles will go on being coated by the formed TiC from the reaction of Ti and the coating carbon and left behind in the composites. However, most of TiC core will be further reacted with the excessive Ti and be transformed into the newly formed TiC with different stoichiometry. The results indicate that it is a feasible method to synthesize TiC in Cu melts by reaction of soluble Ti and ball-milled carbon coating TiC. Keywords: Composites, carbon coating TiC, Cu alloys, Ball-milling

The excellent grain refinement effectiveness and good electrical conductivity is difficult to be simultaneously obtained due to the influence of both the grain boundary and excessive Ti in the usually used refiners, such as Al-5Ti-1B master alloy. In order to solve this problem, in this work, Al-Ti-B mater alloys with less or without excessive Ti but with high refinement potency TiB2 have been tried to prepare, and the grain refinement effectiveness of them and its influence on the electrical conductivity of the refined Al have been investigated. It is found that the grain refinement effectiveness of the Al-Ti-B master alloys prepared using the Al-5Ti-1B and Al-B master alloys as the starting materials at 720 °C is much better than those prepared using the Al-10Ti and Al-B master alloys, which is because that the high refinement potency TiB2 with TiAl3 2DC in the Al-5Ti-B can be kept in the prepared master alloys. As a result, using the prepared Al-Ti-B master alloys as the refiners, both the good grain refinement effectiveness and improved electrical conductivity of Al can be realized. Keywords: Grain refinement, Electrical conductivity, Al, Master alloys

In this paper, nitrogen-doped carbon quantum dots (N-CQDs) were synthesized by a solvothermal method using 1,2,4-triaminobenzene as a carbon precursor. The surface of the synthesized N-CQDs was modified with amino functional groups. The results indicated that N-CQDs had various N-related functional groups and chemical bonds and were amorphous in structure. At the same time, the quantum yield of N-CQDs was 5.11%, and the average lifetime of fluorescence decay was 5.79 ns. The synthesized N-CQDs showed good selectivity for and sensitivity to Ag+. A linear relationship between N-CQDs detection efficiency and Ag+ concentration was observed for concentration ranges of Ag+ corresponding to 0&ndash, 10 &mu, M and 10&ndash, 30 &mu, M. In addition, N-CQDs were used for the detection of trace Ag+ in food packaging material. The silver ion content of the sample determined by the N-CQDs detection method was 1.442 mg/L, with a relative error of 6.24% with respect to flame atomic absorption spectrometry, according to which the Ag+ content was 1.352 mg/L. This indicates that the N-CQDs detection method is reliable. Therefore, the N-CQDs prepared in this paper can detect Ag+ rapidly, simply, and sensitively and are expected to be a promising tool for the detection of trace Ag+ in food packaging materials.

The CCAAT-enhancer-binding protein α (C/EBPα) plays an important role in adipogenic differentiation of adipose-derived stem cells (ASC). Recent studies have shown that microRNAs (miRNAs) participate in the regulation of self-renewal, proliferation, and multi-directional differentiation of ASCs. In the present study, we analyzed the targeting miRNAs on C/EBPα and found that miR-326 played an essential role in it. The results of qPCR confirmed that the expression of miR-326 was reduced in adipogenic differentiation. In addition, the dual-luciferase reporter assay system verified binding between miR-326 and the 3' untranslated region of C/EBPα. Furthermore, transfection of miR-326 into human adipose-derived stem cells caused a significant reduction in C/EBPα. Our results highlight the importance of miR-326 in adipogenic differentiation and provide a reliable basis for clinical treatment of adipose-related diseases. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:2054-2060, 2020. © 2019 American Association for Anatomy.

A method is developed for detecting the concentration of sodium thiocyanate (NaSCN) in milk based on surface-enhanced Raman scattering (SERS) technology. A trichloroacetic acid solution can be used to enhance the SERS signal because of its function in promoting the aggregation of Ag nanoparticles (Ag NPs). Meanwhile, the protein in milk would be precipitated as trichloroacetic acid added and the interference from protein could be reduced during the detection. In this work, the enhancement factor (EF) is 7. 56 &times, 105 for sodium thiocyanate in water and the limit of detection (LOD) is 0.002 mg/L. Meanwhile, this method can be used to detect the concentration of sodium thiocyanate in milk. Results show that SERS intensity increased as the concentration of sodium thiocyanate increase from 10 to 100 mg/L. The linear correlation coefficient is R2 = 0.998 and the detection limit is 0.04 mg/L. It is observed that the concentration of sodium thiocyanate does not exceed the standard in the three kinds of milk. The confirmed credibility of SERS detection is compared with conventional methods.

The grounding grid is an indispensible part in the eletrical system. Nevertheless, the grounding grid materials are susceptible. Considering the small sample size and strong nonlinear feature of the grounding grid corrosion, we introduced a non-excavation corrosion prediction model based on particle swarm optimization extreme learning machine. This model utilized the extreme learning machine to fast deal with the nonlinear relationship, and utilized the particle swarm optimization to search global optimal solution. Compared with generalized regression neural network and BP neural network, the prediction results of this model are more accurate. Thus, this model might have bright future in improving the accuracy of corrosion prediction of grounding grids.

Based on the concept of green and sustainable development, clean heating in northern China has become the key work of local governments, which has been gradually implemented in major cities to meet different heating supply. Therefore, in the new situation, we need to pay more attention to the high quality and sustainable heating mode. Under the new situation, clean heating in northern China needs to focus on optimizing the heating energy structure, which will improve the utilization rate of renewable energy. By strengthening the coordinated planning of the system, we can coordinate the available energy, which will build a multi energy complementary, green and efficient clean heating system. Based on Computer aided technology, we can realize the scheme design of clean heating system. Finally, this paper lists an engineering case.

This paper reported a simple approach to prepare robust conductive/superhydrophobic coating. The hierarchical structure was obtained through the addition of microscale filler (graphite powder and expanded graphite) and nanoscale filler (carbon nanotube). The self-similar structure was obtained through bonding the fillers using the epoxy matrix. Through the combination of the hierarchical and self-similar structures, the as-prepared superhydrophobic coating demonstrated excellent anti-abrasion property, good conductivity, excellent self-cleaning performance in both oil and water environment, outstanding anticorrosive property, and superior thermal stability simultaneously. Moreover, this superhydrophobic coating was achieved by a simple casting method, which has the potential to be used in large scale production.

A highly sensitive nitrite (NO2&minus, ) electrochemical sensor is fabricated using glassy carbon electrode modified with Au nanoparticle and grapheme oxide. Briefly, this electrochemical sensor was prepared by drop-coating graphene oxide-chitosan mixed film on the surface of the electrode and then electrodepositing a layer of Au nanoparticle using cyclic voltammetry. The electrochemical behavior of NO2&minus, on the sensor was investigated by cyclic voltammetry and amperometric i-t curve. The results showed that the sensor exhibited better electrocatalytic activity for NO2&minus, in 0.1 mol/L phosphate buffer solution (PBS) (pH 5.0). The oxidation peak current was positively correlated with NO2&minus, concentration in the ranges of 0.9 &micro, M to 18.9 &micro, M. The detection limit was estimated to be 0.3 &micro, M. In addition, the interference of some common ions (e.g., NO3&minus, CO32&minus, SO42&minus, Cl&minus, Ca2+ and Mg2+) and oxidizable compound including sodium sulfite and ascorbic acid in the detection of nitrite was also studied. The results show that this sensor is more sensitive and selective to NO2&minus, Therefore, this electrochemical sensor provided an effective tool for the detection of NO2&minus

To review the research progress of miRNA regulation in the differentiation of adipose-derived stem cells (ADSCs).The recent literature associated with miRNAs and differentiation of ADSCs was reviewed. The regulatory mechanism was analyzed in detail and summarized.The results indicate that the expression of miRNAs changes during differentiation of ADSCs. In addition, miRNAs regulate the differentiation of ADSCs into adipocytes, osteoblasts, chondrocytes, neurons, and hepatocytes by regulating the signaling pathways involved in cell differentiation.Through controlling the differentiation of ADSCs by miRNAs, the suitable seed cell for tissue engineering can be established. The review will provide a theoretical basis for molecular targeted therapy and stem cell therapy in clinic.总结近年来 miRNA 在调控脂肪干细胞（adipose-derived stem cells，ADSCs）分化中的研究进展。.查阅近年来与 miRNA 和 ADSCs 分化调控相关的文献，详细分析其调节机制，并进行综述。.在 ADSCs 分化过程中，miRNA 的表达会改变，并且 miRNA 可通过调节细胞分化相关的信号通路，调控 ADSCs 定向分化为脂肪细胞、成骨细胞、软骨细胞、神经细胞、肝细胞等。.利用 miRNA 对 ADSCs 分化的调控作用，构建出符合需求的组织工程种子细胞，用于临床分子靶向治疗和干细胞治疗。.

Effects of heat treatment including annealing, especially recovery and recrystallization interannealing on properties of hard drawn aluminum wire were discussed. The experimental results showed that annealing influence properties of hard drawn aluminium wire significantly. Recovery at 180oC on hard drawn aluminum wire improved its electrical conductivity by 0.5% (IACS) without strength decrease. Interrecrystallization annealing at 300oC increased the conductivity of hard drawn aluminum wire by 1.5%IACS, but reduced its strength to 140MPa. Precipitation of supersaturated Fe from solid solution during recrystallization annealing process contributed mainly to the conductivity increasing of hard drawn aluminium wire.

Aluminum and its alloys have achieved extensive industrial application while contamination can cause serious problems to their aesthetic appearance and functionality. Superhydrophobic coating could be a potential solution to the problems. In this study, superhydrophobic coating on the Aluminum alloy surface was prepared via spraying hydrophobic silica nanoparticles suspension. The static water contact angle and sliding angle on the silica nanoparticle deposited aluminum alloy surface were 159±1° and 2°, respectively. In addition, the silica nanoparticle deposited aluminum alloy surface showed excellent self-cleaning property. This method may provide a facile and cost-effective route to form surperhydrophobic surfaces, which would be of technological significance for many practical applications.

We report the remote excited Raman optical activity (ROA) of adenine along Ag plasmonic waveguide. First, the surface plasmons that propagate along Ag nanowire is demonstrated experimentally. Second, the Raman spectra of adenine are measured experimentally. Third, the remote exited ROA by plasmonic waveguide are measured and compared. It is found that the plasmon chirality strongly influenced the molecular ORA by the local surface plasmon and remote plasmon waveguide. The plasmon chirality of nanostructures and the chirality plasmon waveguide should be considered in the experiments for the local and remote measurement.

In this study, we report on a novel potential-responsive hybrid film system for heavy metal removal, which was composed of a layered α-zirconium phosphate (α-ZrP) nanosheet and a conducting polyaniline (PANI)-intercalated chain that functioned as a proton pumping element. The proposed system features a quick responsive uptake/release rate that was about 10 times the adsorption/desorption rate with an open circuit. The potential-responsive film system exhibited a high electroactivity because of an acidic micro-environment for the nitrogen atoms in the PANI chains due to protons available on the electronegative α-ZrP nanosheets and their ion exchangeability. The uniform and dense hybrid film was formed on platinum electrodes using a one-step electrosynthesis based on unipolar pulse electrodeposition (UPED). By simply switching the operating potential applied to the electrode, heavy metal uptake onto the film from aqueous solutions and metal release for film regeneration were accomplished. This film system is shown to be a promising alternative to conventional techniques for heavy metal capture from wastewater.

The isolated carotenoid and pheophytin a, the complex of carotenoid–pheophytin a and a carotenoid–pheophytin a–TiO2 film have been investigated using the time-dependent density functional theory. Charge transfer mechanisms were revealed by the three-dimensional visualization technology. The photoinduced electron transfer, energy transfer and photoelectric conversion efficiency were systematically investigated in the above systems. Furthermore, the charge transfer mechanism and the energy transfer mechanism were studied when the investigated systems were optically excited in electronic transitions.

Cadmium selenide (CdSe) quantum dots (QDs) were synthesized by water phase synthesis method using 3-mercaptopropionic acid (3-MPA) as a stabilizer, and they were applied to the detection of copper ions (Cu2+). The results showed that CdSe QDs have excellent selectivity and sensitivity toward Cu2+. The fluorescence intensity of CdSe QDs decreased with the increase of Cu2+ concentration. The linear range was from 30 nM to 3 &mu, M, and the detection limit was 30 nM. Furthermore, CdSe QDs were used for detecting the concentration of Cu2+ in oysters. The content of Cu2+ was 40.91 mg/kg, which was close to the one measured via flame atomic absorption spectrometry (FAAS), and the relative error was 1.81%. Therefore, CdSe QDs have a wide application prospect in the rapid detection of copper ions in food.

To observe the clinical efficacy on migraine treated with acupoint implantation.Sixty cases of migraine were randomized into a implantation group and an electroacupuncture (EA) group, 30 cases in each one. In the implantation group, implantation was used at Fengchi (GB 20), Taiyang (EX-HN 5), Waiguan (TE 5), Yanglingquan (GB 34), etc., once every 2 weeks, for 4 weeks totally. In the EA group, the acupoints were the same as the implantation group, and EA was applied to Fengchi (GB 20) and Taiyang (EX-HN 5), Yanglingquan (GB 34) and Zusanli (ST 36), once every two days, for 4 weeks totally. The visual analogue scale (VAS) was adopted before and after treatment and the clinical efficacy was compared between the two groups.After treatment, VAS score was reduced in the implantation group and the EA group as compared with that before treatment (both P0.01). After treatment, VAS score in the implantation group was lower than that in the EA group (P0.01). The difference in VAS score before and after treatment in the implantation group was improved apparently as compared with that in the EA group (P0.01). The total effective rate in the implantation group was higher than that in the EA group (P0.05).The acupoint implantation reduces VAS score in the patients of migraine and its clinical efficacy is better than that in the EA group. The therapy presents the long-term clinical effect and deserves to be promoted in clinical practice.