Early diagnosis of cancers is critical for prevention of metastasis and early treatment. The study reports an electrochemical sensor for detection of cancer cell based on folic acid (FA) and ...octadecylamine (OA)-functionalized graphene aerogel microspheres (FA-GAM-OA). Citric acid was mixed with FA and OA and heated at 180 °C for 4 h to form FA and OA-functionalized graphene oxide. The graphene oxide was employed as solid particle surfactant for stabilizing toluene-in-water emulsion. The graphene oxide sheets in the emulsion were self-assembled into graphene oxide gel microspheres on the water/toluene interfaces. Followed by free drying and reduction in H2 at 400 °C for 5 h. The resulted FA-GAM-OA shows a sphere-like structure with an average diameter of 1.2 µm, the rich of open-pores and folic acid groups. Small particle size and good hydrophilicity make FA-GAM-OA can be dispersed in water for sensor preparation. The small size of graphene sheets and their self-assembly avoid a serious agglomeration of graphene sheets. The FA-GAM-OA offers a large surface area (1723.6 m2 g−1) and high electronic conductivity (2978.2 S m−1). The covalent linkage and ordered alignment of folic acid groups at FA-GAM-OA surface achieve to specific cancer cell capture with high capture efficiency. The electrochemical sensor based on FA-GAM-OA exhibits extremely good analytical performances in detection of liver cancer cells with a linear range of 5–105 cell mL−1 giving a low detection limit of 5 cells mL−1 (S/N = 3). The method was successfully applied to electrochemical detection of liver cancer cells in whole blood.
•The study develops a folic acid and octadecylamine functionalized graphene aerogel.•Folic acid heads were covalently linked at graphene as a capture probe for cancer cell.•The graphene aerogel offers large specific surface, and electronic/ion conductivity.•Electrochemical sensor based on graphene exhibits a high sensitivity and selectivity.•The study offers approach for building on graphene aerogel for further application.
Catalytic borrowing hydrogen reaction is a very attractive transformation in the field of C‐alkylation reaction. In this work, a new Zr (Zirconium)‐containing coordination polymer containing ...unsymmetric indolyl dicarboxylic acid 1‐(carboxymethyl)‐1H‐indole‐5‐carboxylic acid (H2CIA) was synthesized by the way of a solvothermal synthetic route and characterized by powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption‐desorption, fourier transform infrared spectroscopy and X‐ray photoelectronic spectroscopy (XPS). The coordination polymer Zr‐CIA was employed as the catalyst for C‐alkylation of acetophenone derivatives in the presence of benzyl alcohol. In addition, Zr‐CIA catalyst was also observed to be effective in the reaction of alcohols with alcohols and high yields of alkylation products were achieved. Mechanism investigations were also conducted to better understand the catalysts and transformations. Meanwhile, the Zr‐CIA could be reused at least five times without a notable decrease in activity and selectivity.
Abstract This research paper presents a comprehensive investigation into the utilization of color image processing technologies and deep learning algorithms in the development of a robot vision ...system specifically designed for 8-ball billiards. The sport of billiards, with its various games and ball arrangements, presents unique challenges for robotic vision systems. The proposed methodology addresses these challenges through two main components: object detection and ball pattern recognition. Initially, a robust algorithm is employed to detect the billiard balls using color space transformation and thresholding techniques. This is followed by determining the position of the billiard table through strategic cropping and isolation of the primary table area. The crucial phase involves the intricate task of recognizing ball patterns to differentiate between solid and striped balls. To achieve this, a modified convolutional neural network is utilized, leveraging the Xception network optimized by an innovative algorithm known as the Improved Chaos African Vulture Optimization (ICAVO) algorithm. The ICAVO algorithm enhances the Xception network's performance by efficiently exploring the solution space and avoiding local optima. The results of this study demonstrate a significant enhancement in recognition accuracy, with the Xception/ICAVO model achieving remarkable recognition rates for both solid and striped balls. This paves the way for the development of more sophisticated and efficient billiards robots. The implications of this research extend beyond 8-ball billiards, highlighting the potential for advanced robotic vision systems in various applications. The successful integration of color image processing, deep learning, and optimization algorithms shows the effectiveness of the proposed methodology. This research has far-reaching implications that go beyond just billiards. The cutting-edge robotic vision technology can be utilized for detecting and tracking objects in different sectors, transforming industrial automation and surveillance setups. By combining color image processing, deep learning, and optimization algorithms, the system proves its effectiveness and flexibility. The innovative approach sets the stage for creating advanced and productive robotic vision systems in various industries.
Patients with advanced or recurrent cervical cancer have poor prognosis, and their 1-year survival is only 10%-20%. Chemotherapy is considered as the standard treatment for patients with advanced or ...recurrent cervical cancer, and cisplatin appears to treat the disease effectively. However, resistance to cisplatin may develop, thus substantially compromising the efficacy of cisplatin to treat advanced or recurrent cervical cancer. In this article, we systematically review the recent literature and summarize the recent advances in our understanding of the molecular mechanisms underlying cisplatin resistance in cervical cancer.
The selective electrocatalytic conversion of CO2 into useful products is a major challenge in facilitating a closed carbon cycle. Here, on the basis of first-principles calculations combined with ...computational hydrogen electrode model, we report a curvature-dependent selectivity of CO2 reduction on cobalt–porphyrin nanotubes which are thermodynamically stable, displaying tunable geometric and electronic properties with tube radius. We have found that CO production is preferred on nanotubes with larger diameter, and the predicted current density from microkinetics is larger than that on Au, the best metal catalyst for CO production from CO2 electroreduction. In contrast, highly curved nanotubes with small radii tend to further catalyze CO reduction to CH4 gas and the overpotential is much lower in comparison with the cases on Cu surfaces. The selectivity and the feasibility of synthesis make cobalt–porphyrin nanotubes very promising for CO2 conversion.
The study reports on the synthesis of a graphene aerogel@octadecylamine-functionalized carbon quantum dots (GA@O-CQDs). The graphene oxide aqueous dispersion, O-CQDs aqueous dispersion and toluene ...were strongly mixed to make a toluene-in-water Pickering emulsion. The graphene oxide sheets in the aqueous phase are reduced by hydrazine hydrate, diffuse into the toluene droplets, and self-assemble into graphene oxide microgels. This is followed by freeze-drying and thermal annealing to obtain the GA@O-CQDs hybrid that has a three-dimensional structure of several microns. It was dispersed in ethanol and deposited on a glassy carbon electrode. The modified electrode was applied to differential pulse voltammetric determination of acetaminophen, best at a peak potential of 0.15 V (vs. Ag/AgCl). Figures of the merit include a wide linear response range (0.001–10 μM) and a 0.38 nM of the detection limit (S/
N
= 3). The assay has been applied to the determination of acetaminophen in tablets.
Graphical abstract
Schematic presentation of the synthesis of graphene aerogel@octadecylamine-functionalized carbon quantum dots. The synthesis achieves to the intimate chemical and electrical contact between graphene and carbon quantum dots. An electrode modified with the hybrid exhibits ultra high sensitivity for detection of acetaminophen.
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•We report one concept for synthesis of atomically dispersed RuO2-graphene quantum dot-graphene.•Ultrasmall RuO2 was atomically dispersed on graphene sheets with a very high Ru ...loading of 4.2%•The intimate contacts achieve to formation of double Schottky heterojunctions at the interfaces.•Ru in hybrid brings an increased capacitance of more than five times of the theoretical value of RuO2.•The study offers one way for synthesis of graphene-based composites with high catalytic activity.
Poor capacity and cycle stability limit many applications of supercapacitors in wearable electronic devices. The study reports synthesis of atomically dispersed RuO2 (AD-RuO2)-tryptophan functionalized graphene quantum dot (Trp-GQD)-graphene (G) hybrid. Trp-GQD was bound to graphene oxide (GO) by π-π stacking and then combined with Ru3+ ion via Ru-N coordination bond to form Ru-Trp-GQD-GO complex. Followed by partial reduction into graphene gel with hydrazine hydrate, thermal reduction in N2 and oxidation in air in sequence. The resulting AD-RuO2-Trp-GQD-G offers well-defined three-dimensional structure and high Ru loading of 4.2%. RuO2 was atomically dispersed on the graphene sheets. The intimate contacts of Trp-GQD with G and RuO2 create the double Schottky heterojunctions at the interfaces and results in an excellent catalytic activity. The AD-RuO2-Trp-GQD-G electrode exhibits high capacitance of 503.7F g−1 at 1 A g−1. The value is much higher than that of graphene electrode (160F g−1) and G-Trp-GQD electrode (192F g−1). This verifies that the introduction of Ru per gram can bring an increased capacitance of 7421.4F, which is more than five times of the theoretical value of RuO2 electrode. The flexible supercapacitor displays high capacitance (354F g−1 at 0.5 A g−1), rate-capacity (186F g−1 at 20 A g−1) and cycling stability (99.6% capacity retention after 10,000 cycles at 10 A g−1). The supercapacitor is able to deliver a power density of up to 52000 W kg−1 and energy density of up to 332 Wh Kg−1 and good application prospect in wearable electronic devices.
The wheelset coaxial wheel diameter difference is one of the most common wheel faults of railway vehicles. The existence of the wheelset coaxial wheel diameter difference may lead to the off-load ...operation of vehicles, resulting in abnormal wheel tread wear, leading to the deterioration of the wheel-rail contact relationship, resulting in the deterioration of the vehicle's operating stability and comfort, and even leading to an increase in the derailment coefficient, affecting the running safety. In order to monitor the freight car wheelset coaxial wheel diameter difference online, a vehicle-track coupling dynamics model based on a trackside detection method was established, and the response of rail lateral displacement under the condition of the wheelset coaxial wheel diameter difference was analyzed. The results show that the existence of the wheelset coaxial wheel diameter difference can lead to a deviation in the vehicle's run, with an increase in the wheelset coaxial wheel diameter difference and an increase in the lateral offset of wheelset increases. The impact of vehicle unbalance loading on the lateral movement of the wheelset is much smaller than that of the wheelset coaxial wheel diameter difference. The existence of the wheelset coaxial wheel diameter difference can be better reflected by detecting the wheelset's lateral displacement. On straight line, the variation of lateral displacement has no infection of vehicle speed, but shows a quadratic growth trend with the wheelset coaxial wheel diameter difference. Based on this, the mapping relationship between the wheelset coaxial wheel diameter difference and wheelset lateral displacement can be obtained. Through a mapping relationship, the size of the wheelset coaxial wheel diameter difference can be reversed precisely through the detection of a trackside lateral movement monitoring system. The reliability of the identification method was verified with a specific test on the trackside monitoring system.
The patriarchal structure of the traditional Chinese family suggests that sons, more than daughters, provide financial support to elderly parents. The norm of receiving support in old age primarily ...from sons, however, may have been undermined by dramatic demographic, economic, and cultural changes occurring over the last several decades in China, especially in urban areas. We examine gender differences in adult children's financial support to parents using a recent data set ("Study of Family Life in Urban China") collected in 1999 (N = 1,801). The results show that married daughters, especially those living with parents, provide more financial support to parents than married sons do. This significant gender difference can be primarily explained by daughters' resources, such as education and income.
There are two key motivations for this paper: (1) the need to respond to the often observed rejections of efficiency studies’ results by management as they claim that a single-perspective evaluation ...cannot fully reflect the operating units’ multi-function nature; and (2) a detailed bank branch performance assessment that is acceptable to both line managers and senior executives is still needed. In this context, a two-stage Data Envelopment Analysis approach is developed for simultaneously benchmarking the performance of operating units along different dimensions (for line managers) and a modified Slacks-Based Measure model is applied for the first time to aggregate the obtained efficiency scores from stage one and generate a composite performance index for each unit. This approach is illustrated by using the data from a major Canadian bank with 816 branches operating across the nation. Three important branch performance dimensions are evaluated: Production, Profitability, and Intermediation. This approach improves the reality of the performance assessment method and enables branch managers to clearly identify the strengths and weaknesses in their operations. Branch scale efficiency and the impacts of geographic location and market size on branch performance are also investigated. This multi-dimensional performance evaluation approach may improve management acceptance of the practical applications of DEA in real businesses.
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