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A biodegradable delivery platform is constructed for controlled drug delivery. Carboxylated biodegradable mesoporous silica nanoparticles (COOH–BMSNs) are synthesized to load the chemotherapy drug methotrexate (MTX), and the mesopores of BMSN are blocked by ZnO quantum dots (QDs) through an amidation reaction to encapsulate the loaded MTX. The ZnO QDs are decomposed under mildly acidic conditions which is characteristic of a tumor microenvironment, resulting in the release of MTX; additionally, glutathione (GSH) can reduce the disulfide bonds (−S–S−) in a BMSN into sulfhydryl (−SH), causing the decomposition of the BMSN and the release of MTX. Therefore, the responsiveness of pH and GSH to MTX delivery can be achieved with ZnO–BMSN–MTX. Notably, in vitro cytotoxicity testing reveals that the drug-free carrier (ZnO–BMSN) exhibits good biocompatibility, whereas the controlled delivery platform (ZnO–BMSN–MTX) exhibits significant cytotoxicity against SMMC-7721 tumor cells benefiting from the synergistic effect of MTX and Zn2+.

Safety issue is the main concern for current lithium-ion batteries (LIBs), especially for the high energy density cells based on nickel-rich oxide/Si-C chemistries, which could experience violent explosion and intense burning with the temperature exceeding 1000 °C during thermal runaway (TR). And moreover, within a module/system, the TR of a single cell might trigger the TR of neighboring cells, usually called TR propagation, leading to a fire accident or even a server disaster. The objective of this work is to introduce an aerogel sheet with extremely low thermal conductivity and high thermal stability to block the TR propagation. The silica aerogel sheet (SAS) is synthesized via a sol-gel process followed by supercritical fluid drying. The thermal conductivities of the obtained SAS are 0.018, 0.029, 0.043 and 0.074 W (m·K) −1at 20 °C, 300 °C, 500 °C and 800 °C, respectively. A simple module is constructed with two LIBs (NCM811/Si-C, 320 Wh/kg) sandwiched with a piece of SAS with various thicknesses (1.2–2.8 mm). The results show that the SAS of 1.2 mm or 1.8 mm thickness cannot stop the TR propagation. The propagation times to next cell are 50 (1.2 mm) and 106 s (1.8 mm), respectively. While the SAS of 2.3 mm or thicker can suppress the TR propagation successfully, and moreover, protect the neighboring cell from any voltage drop/collapse. The microstructure and thermal conductivity of the SAS after TR experiments do not show evident change, revealing that the as-prepared SAS is thermally stable during the violent TR process. This work provides new insights for battery thermal management system (BTMS).

To date, achieving enantioselective electroanalysis for electrochemically silent chiral molecules is still highly desired. Here, an ionic covalent organic framework (COF) consisting of the pyridinium cation was derived from the tripyridinium Zincke salt and 1,4-phenylenediamine in a one-pot reaction. The electrochemical measurements revealed that the ionic backbone contributed to the electron transfer with a low charge transfer resistance. Besides, the π–π+interaction between the pyridinium cation and ferrocenyl unit can promote the absorption of electroactive chiral ferrocenyl reagents into the hole of COF, so as to afford the electrochemical signals by themselves, replacing the testing enantiomers. As a result, the electroactive complex used as an electrochemical platform was highly effective at enantiomerically recognizing amino alcohols (prolinol, valinol, leucinol, and alaninol) and amino acids (methionine, serine, and penicillamine), giving the ratios of current intensity between l- and d-enantiomers in the range of 1.46–1.72. Moreover, the density functional theory calculations determined the possible intermolecular interactions between the testing enantiomers and chiral selector: namely, hydrogen bonds and electrostatic attractions. Overall, the present work offers an effective strategy to enlarge the electrochemical scope for chiral recognition based on electroactive chiral COFs.

A mass production route to catalysts for the oxygen reduction reaction (ORR) is crucial for their end-use application. To date, the direct manufacture of ORR catalysts through simple and economic manufacturing routes remains a challenge, with current approaches relying on convoluted processes using expensive components. Here, a straightforward and cost-effective method is developed to fabricate metal hybrid carbon/titania composite aerogels (CTA-M) as ORR catalysts, which was obtained via carbonizing metal hybrid resorcinol–formaldehyde (RF)/titania composite aerogels at 900 °C in an inert atmosphere. The effect of metal nitrate, including La, Sm, Zr, Cr, Fe, and Cu nitrates, on the structure and ORR performance was investigated. The high porosity and specific surface area enabled CTA-M with a high mass transfer performance. The high asymmetry of anatase leads to the presence of oxygen vacancies in the crystal structure of CTA-M, which maintains the electrostatic equilibrium of the crystal structure, which verifies that the catalytic activity of anatase is superior to that of rutile, whereas the non-homogeneous product enhances the electrical conductivity, which further affects the catalytic activity of the ORR. Trace metal doping can modulate the electronic structure and composition of CTA-M. Iron nitrate doping carbon/titania aerogel (CTA-Fe-A) showed the best pore structure and oxygen adsorption performance. The specific surface area and pore volume of CTA-Fe-A were 720 m2g–1and 1.12 cm3g–1, respectively. The onset potential, half-wave potential, and ultimate current density were 0.82 V, 0.74 V, and 4.96 mA cm–2, respectively. It is expected that this synthesis technique and the resulting CTA-M could be used as a method for large-scale commercial production of ORR catalysts, thus enabling the use of these materials in a broad spectrum of industrial applications.

Although several studies related with the electrochemiluminescence (ECL) technique have been reported for chiral discrimination, it still has to face some limitations, namely, complex synthetic pathways and a relatively low recognition efficiency. Herein, this study introduces a facile strategy for the synthesis of ECL-active chiral covalent organic frameworks (COFs) employed as a chiral recognition platform. In this artificial structure, ruthenium(II) coordinated with the dipyridyl unit of the COF and enantiopure cyclohexane-1,2-diamine was harnessed as the ECL-active unit, which gave strong ECL emission in the presence of the coreactant reagent (K2S2O8). When the as-prepared COF was used as a chiral ECL-active platform, clear discrimination was observed in the response of the ECL intensity toward l- and d-enantiomers of amino acids, including tryptophan, leucine, methionine, threonine, and histidine. The biggest ratio of the ECL intensity between different configurations was up to 1.75. More importantly, a good linear relationship between the enantiomeric composition and the ECL intensity was established, which was successfully employed to determine the unknown enantiomeric compositions of the real samples. In brief, we believe that the proposed ECL-based chiral platform provides an important reference for the determination of the configuration and enantiomeric compositions.

Electrochemiluminescence (ECL), integrating the characteristics of electrochemistry and fluorescence, has the advantages of high sensitivity and low background. However, only a few studies have been reported for enantioselective sensing based on the ECL-active platform because of the huge challenges in constructing tunable chiral ECL luminophores. Here, we developed a facile strategy to design and prepare ECL-active chiral covalent organic frameworks (COFs) Ph-triPy+-(R)-Ru(II) for enantioselective sensing. In such an artificial structure, the ionic skeleton of COFs was beneficial to the electron transfer on the working electrode surface and the chiral Ru-ligand was used as the chiral ECL-active luminophore. It was found that Ph-triPy+-(R)-Ru(II) coupled with sodium persulfate (Na2S2O8) as the coreactant exhibited obvious ECL signals. More importantly, a clear difference toward l- and d-enantiomers was observed in the response of the ECL intensity, resulting in a uniform recognition law. That is, for amino alcohols, d-enantiomers (1 mM) measured by Ph-triPy+-(R)-Ru(II) showed a higher ECL intensity compared with l-enantiomers. Differently, amino acids (1 mM) gave an inverse recognition phenomenon. The ECL intensity ratios between l- and d-enantiomers (1 mM) are in the range of 1.25–1.94 for serine, aspartic acid, glutamic acid, valine, leucine, leucinol, and valinol. What is more interesting is that the ECL intensity was closely related to the concentration of l-amino alcohols and d-amino acids, whereas their inverse configurations remained unchanged. In a word, the present concept demonstrates a feasible direction toward chiral ECL-active COFs and their potential for efficient enantioselective sensing.

ABSTRACTChemotherapeutic resistance is one of the most common reasons for poor prognosis of patients with nasopharyngeal carcinoma (NPC). We found that CENPN can promote the growth, proliferation and apoptosis resistance of NPC cells, but its relationship with chemotherapeutic resistance in NPC is unclear. Here we verified that the CENPN expression level in NPC patients was positively correlated with the degree of paclitaxel (PTX) resistance and a poor prognosis through analysis of clinical cases. VAMP8 expression was significantly increased after knockdown of CENPNby transcriptome sequencing. We found in cell experiments that CENPN inhibited macroautophagy/autophagy and VAMP8 expression and significantly increased PTX resistance. Overexpression of CENPNreduced the inhibitory effects of PTX on survival, cell proliferation, cell cycle progression and apoptosis resistance in NPC cells by inhibiting autophagy. In turn, knockdown of CENPNcan affect the phenotype of NPC cells by increasing autophagy to achieve PTX sensitization. Sequential knockdown of CENPNand VAMP8reversed the PTX-sensitizing effect of CENPNknockdown alone. Experiments in nude mice confirmed that knockdown of CENPNcan increase VAMP8 expression, enhance autophagy and increase the sensitivity of NPC cells to PTX. Mechanistic studies showed that CENPN inhibited the translocation of p-CREB into the nucleus of NPC cells, resulting in the decreased binding of p-CREB to the VAMP8promoter, thereby inhibiting the transcription of VAMP8. These results demonstrate that CENPN may be a marker for predicting chemotherapeutic efficacy and a potential target for inducing chemosensitization to agents such as PTX.Abbreviations:3-MA: 3-methyladenine; ATG5: autophagy related 5; CENPN: centromere protein N; CQ: chloroquine; CREB: cAMP responsive element binding protein; ChIP: chromatin immunoprecipitation assay; IC50: half-maximal inhibitory concentration; LAMP2A: lysosomal associated membrane protein 2A; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NPC: nasopharyngeal carcinoma; NPG: nasopharyngitis; oeCENPN: overexpressed CENPN; PTX: paclitaxel; RAPA: rapamycin; RNA-seq: transcriptome sequencing; shCENPN: small hairpin RNA expression vector targeting the human CENPNgene; shCENPN-shVAMP8: sequential knockdown targeting the human CENPNgene and VAMP8gene; shVAMP8: small hairpin RNA expression vector targeting the human VAMP8gene; TEM: transmission electron microscopy; TIR: tumor inhibitory rate; VAMP8: vesicle associated membrane protein 8.

Mesoporous manganese dioxide (mMnO2) was first synthesized for the loading of methotrexate (MTX), and then dopamine was in situ polymerized on the surface of the MTX‐loaded mMnO2(mMnO2‐MTX) in an alkaline solution to encapsulate the drug in the mesopores of mMnO2. Both low pH and glutathione (GSH) can result in the degradation of mMnO2and poly(dopamine) (PDA), and thus the delivery of MTX from the mMnO2‐MTX‐PDA can be triggered by low pH and GSH. Near‐infrared (NIR) light‐responsive delivery of MTX can be achieved owing to the outstanding photothermal conversion capability of PDA; on the other hand, the mMnO2‐MTX‐PDA can be utilized for photothermal therapy under the irradiation of NIR light due to the elevated temperature. The results of cytotoxicity test demonstrate that the pH, GSH, and NIR light tri‐responsive drug‐controlled delivery system has excellent biocompatibility, while exhibits pronounced growth inhibition against murine breast tumor cell line 4T1. Synthesis of mMnO2‐MTX‐PDA and pH, GSH, and NIR light triggered delivery of MTX.

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The analyses of the numerical stability and dispersion of the 3-D hybrid implicit–explicit finite-difference time domain (3-D HIE-FDTD), including the lumped elements, are systematically researched. Specifically, three lumped elements of the resistor, inductor, and capacitor are discussed, and the explicit, semi-implicit, and implicit schemes are discussed. First, according to the techniques of von Neumann and Jury criterion, the numerical stability of the extended 3-D HIE-FDTD method is studied. Research results demonstrate that: 1) as to the lumped resistor and inductor under the semi-implicit and implicit schemes, and capacitor under the implicit scheme, the numerical stability condition of the extended 3-D HIE-FDTD method is consistent with the 3-D HIE-FDTD method unloaded lumped elements and 2) for the lumped resistor and inductor under the explicit scheme, the numerical stability condition becomes more stringent than that of the 3-D HIE-FDTD method unloaded case, which is dependent on the value of the resistance or inductance. Second, based on the Norton equivalent circuit, the numerical dispersion characteristics of the extended 3-D HIE-FDTD method are analyzed, and the numerical impedance for the lumped elements under different difference schemes is deduced. Finally, to testify the validity of the theoretical results, the numerical results of microstrip circuits are provided.

The numerical stability and dispersion analysis of the extended 2-D finite-difference time-domain (2-D-FDTD) method are systematically studied. Particularly, three different passive linear lumped elements including the resistor, inductor, and capacitor are analyzed, respectively. Moreover, three different formulations of the explicit, semi-implicit, and implicit schemes are discussed, respectively. Furthermore, by combining the von Neumann technique and Jury criterion, the numerical stability of the extended 2-D-FDTD method is analyzed, which has not been reported thus far. Theoretical results show that: 1) for the resistor, the stability condition is same as the FDTD method unloaded case; 2) for the inductor, in the explicit and implicit schemes, the stability is connected with the value of the inductance; 3) for the semi-implicit scheme, the stability is independent of the value of the inductance; and 4) for the capacitor, the stability relationship is related to both the mesh size and the value of the capacitance. On the other hand, based on the Norton equivalent circuit, the analysis of the numerical dispersion of the extended 2-D-FDTD is presented; and some interesting theoretical results are deduced. Finally, the microstrip circuits including the three lumped elements are simulated to demonstrate the validity of the theoretical results.

A 3D printer uses machine vision to solve a problem that has plagued 3D inkjet printers, increasing the range of materials that can be used, and enabling the rapid production of complex objects such as a robot hand.

Reliable chiral discrimination of enantiomers with simple devices is of great importance for chiral analysis. Here, a chiral sensing platform is developed for chiral discrimination through two different modes: electrochemistry and temperature. Au nanoparticles (AuNPs) are grown in situ on the nanosheets of MXene by utilizing the strong metal reduction ability of MXene, which can be further used for the anchoring of N-acetyl-l-cysteine (NALC), a commonly used chiral source, through Au–S bonds. Owing to the excellent electrical conductivity and photothermal conversion efficiency of MXene, the resultant MXene-AuNPs-NALC is applied in the construction of a chiral sensing platform for the discrimination of tryptophan (Trp) enantiomers through two different modes: electrochemistry and temperature. Compared with conventional single-mode chiral sensors, the proposed chiral sensing platform can integrate two different indicators (currents and temperature) into one chiral sensor, greatly improving the reliability of chiral discrimination.

This paper presents the analysis and comparisons between the Surface Permanent Magnet (SPM) and Interior Permanent Magnet (IPM) Machines about their loss and efficiency characteristics. To calculate the airgap flux density and torque, an analytic model is created. The loss functions are derived using the key design parameters which have a great influence on the loss characteristic. As a result, the efficiency can be calculated. The relationship between the design parameters and efficiency characteristic is investigated adopting the proposed method. The efficiency of different driving cycles is also calculated and compared. Finally, some principles are obtained to help the initial design to fit the actual loading requirement. The analytic results are compared with those by Finite Elements Analysis (FEA), and a prototype is made and tested to validate the proposed method and analysis.

The objective of this research was to develop new hydrophobic silica aerogel microspheres (HSAMs) with water glass and hexmethyldisilazane for oil adsorption. The effects of the hexmethyldisilazane concentration and drying method on the structure and organic liquid adsorption capacity were investigated. The hexmethyldisilazane concentration of the modification solution did not influence the microstructure and pore structure in a noteworthy manner, which depended more on the drying method. Vacuum drying led to more volume shrinkage of the silica gel microsphere (SGM) than supercritical CO2drying, thus resulting in a larger apparent density, lower pore volume, narrower pore size distribution, and more compact network. Owing to the large pore volume and pore size, the HSAMs synthesized via supercritical CO2drying had a larger organic liquid adsorption capacity. The adsorption capacities of the HSAMs with pore volumes of 4.04–6.44 cm3/g for colza oil, vacuum pump oil, and hexane are up to 18.3, 18.9, and 11.8 g/g, respectively, higher than for their state-of-the-art counterparts. The new sorbent preparation method is facile, cost-effective, safe, and ecofriendly, and the resulting HSAMs are exceptional in capacity, stability, and regenerability.

Radiation detection systems for security applications are often equipped with neutron sensors and are required to promptly respond with an alarm if the neutron flux exceeds the background level. As the ambient neutron flux is essentially caused by cosmic radiation, this background could be evaluated by assessing the rate of muons crossing the gamma-ray detector which is comprised in such systems anyway. A study performed with a commercial backpack radiation detection system demonstrates the feasibility of this approach, assuming the gamma spectrometer is capable of discriminating muon signals from energetic events caused by the gamma-ray cascades following neutron captures. This requires a dynamic range exceeding the usual 3–4 MeV. The instrument used provided standard spectroscopy up to 10 MeV and facilitated charge-loss compensated spectroscopy up to 1 GeV, which allowed a separate assessment of normal gamma events (< 3 MeV), neutron-capture (n.c.) gamma events (3–7 MeV), and muon events (>10 MeV). In this case, the rate of n.c. gamma events can be used as a neutron indicator on its own, while the muon rate signals the ambient neutron background level.

Submerged macrophytes play an important role in structuring biological communities. Aquatic fungi are an important component of aquatic ecosystems. However, little is known about the effects of submerged macrophytes on fungal communities. In this study, we take an integrative approach to ascertain the influence of Potamogeton lucensL. on the structure, and function of the fungal communities from different areas (with/without P. lucensL.) of two sample types (water/sediment) using Illumina MiSeq metabarcoding and qPCR. Fungal alpha diversity in area cultivated with P. lucensL. was higher than in those without P. lucensL., but the opposite trend was found in the sediment samples. The copy number of the nuclear ribosomal internal transcribed spacer (ITS) region in the sediment samples was higher in area with than without P. lucensL. We found 15 and 3 significantly different genera in the sediment and water samples, respectively. At the operational taxonomic unit (OTU) level, the fungal communities were found to be clustered according to area (with/without P. lucensL) and source (water/sediment). Total phosphorus, alkali-hydrolyzable nitrogen, and NO2−contents influenced the fungal community in the PL water samples. It was positively correlated with alkali-hydrolyzable nitrogen, content in the P. lucensL sediments samples. For the water samples, plant pathogens were significantly higher in P. lucensL area, while wood saprotrophs, plant pathogenic on pollen, fungal parasites, dung saprotroph, and animal pathogens were significantly higher in P. lucensL area. Our study confirmed that submerged macrophytes changed the fungal community composition in both sediment and water, demonstrating that submerged macrophytes affect the transportation and cycling of nutrients related to fungi in lake ecosystems.

This paper proposes a method to create the efficiency map of the Permanent Magnet (PM) assisted Synchronous Reluctance Machine (PMa-synRM). Rather than improve the classic loss models, it is proposed primarily to provide a tool to investigate the mechanism between design parameters and efficiency characteristics. Firstly, an analytic model is built to predict the flux density in airgap and electromagnetic torque. Then the loss distribution is analyzed and the parameters that have a significant impact on the losses are selected to derive loss functions. The output results with corresponding control strategies can be obtained, including the torque, speed and loss. A program to create efficiency map has been established based on the proposed method. The influence of design parameters on the loss and efficiency characteristics is studied using the loss coefficients which obtained by the proposed loss functions. Several criteria are concluded to guide the initial design toward expected efficiency characteristics. The results obtained using the proposed method are compared with Finite Elements Analysis (FEA) results, and experiment platform is also constructed to validate the proposed method.

A novel Zn‐coordination covalent porphyrin assembly (TCPP‐BZA‐Zn) is designed. The assembly structure is synthesized through the amidation reaction between the porphyrin terminal carboxyl group and the amino group of benzylamine (BZA), and further assembled through π–π stacking. In particular, the inherently ordered structure of TCPP‐BZA‐Zn with Zn as the catalytic active center endows the porphyrin assembly structure with several obvious advantages, such as high ion transport properties and high electrocatalytic performance. In the presence of hydrogen peroxide as a co‐reaction reagent, TCPP‐BZA‐Zn/GCE showed excellent ECL behavior. The amplification phenomenon of ECL was further studied by cyclic voltammetry and the corresponding mechanism was proposed. Based on TCPP‐BZA‐Zn, an electrochemiluminescence sensor was constructed for copper ion detection. The ECL intensity of the sensor shows a good linear relationship with the concentration of copper ion in the range of 10 nM–1 mM, and the detection limit is 1.3 nM.

In this paper, a novel hybrid excited axial field flux-switching permanent magnet (HEAFFSPM) machine is presented, of which the high torque capability and flexible flux regulation make it suitable for EV application. The field regulation principle of the machine is investigated, and the analogical saturation effect at pro-magnetized condition is revealed. Then the influence of the machine design parameters on the field regulation capacity and output torque of a 3-phase 6/10 stator/rotor-pole HEAFFSPM machine are analyzed by 3-D finite element analysis (FEA) method under univariate optimization condition. With the slight decrease of the electromagnetic torque, both the analogical saturation effect under pro-magnetized condition and the high flux regulation capacity are effectively improved with multivariable optimization via design of experiments (DOE) method. Finally, a prototype has been manufactured and the analysis result is validated with the experiment result.

A resorcinol-formaldehyde/titanium oxide (RF/TiO2) aerogel was synthesized via an acid-catalyzed sol-gel process followed by CO2supercritical drying. After the thermal treatment of the RF/TiO2aerogel, the partially reduced TiO2aerogel (PRTA) was prepared as a catalyst for oxygen reduction reaction (ORR). Magnéli phase (Ti4O7) and anatase with oxygen vacancies were formed in PRTA. The specific surface area and the pore volume of PRTA were 637 m2g-1and 1.72 cm3g-1, respectively. RF-derived carbon, TiO2(a)/TiO2(r), and TiO2(a) were also prepared to estimate the origin of ORR activity. The Eonset, E1/2, and Jlimitwere 0.75 V, 0.65 V, and 3.33 mA cm-2, respectively. Its stability outperformed Pt/C. This preparation method is inspiring for preparing the Magnéli phase with a better pore structure.A partially reduced TiO2aerogel catalyst with high specific surface area and high pore volume was synthesized by the sol-gel method, CO2supercritical drying and in-situ carbothermal treatment. The sample showed appealing ORR catalytic activity due to the formation of Ti4O7(Magnéli phase) and anatase, which contains abundant oxygen vacancies and structural defects.

AbstractIndented impressions can be left on the surface beneath a document when it is written on. In the absence of this document, electrostatic detection devices can be used to reveal the underneath previously written information. However, there are instances where the toner used to develop these indentations has to be substituted with alternative application, under unexpected circumstances, such as the supply chain disruption during the ongoing global pandemic. This study aimed to verify the use of erasable marker pen ink as an alternative application for the development of indentations. The procedure was optimized and evaluated, and its performance in deciphering indented impressions from 11 different underlying surfaces was compared to a conventional electrostatic detection device that applied toner to develop indentation. Electrostatic device with toner application using cascade developer method has successfully developed indented impressions from all surfaces, except for the coated glossy paper. In contrast, the application of erasable marker pens revealed indentation successfully from not only the coated glossy paper but also six other common writing surfaces. While the toner is a reliable application for deciphering indentations, the application of erasable marker ink pen can be used in the event when toners are unavailable but also on surfaces such as glossy paper, where application of toners to develop indentation may not provide satisfactory results.

A simple drug controlled delivery system is facilely designed for pH‐responsive delivery of methotrexate (MTX), an anticancer drug. Aminated mesoporous silica nanoparticles (AMSNs) were first synthesized for the loading of MTX, and then the MTX‐loaded AMSN (AMSN‐MTX) was encapsulated with hyaluronic acid (HA) through electrostatic attractions. Successful preparation of the HA‐encapsulated AMSN‐MTX (AMSN‐MTX‐HA) is confirmed by different characterizations such as scanning electron microscopy, Fourier transform infrared, x‐ray diffraction, and so on. Because the protonation/deprotonation of HA is closely related to pH, the electrostatic interactions between HA and AMSN depend closely on the pH of the medium and thus pH‐responsive delivery of MTX is achieved. The release kinetic data of MTX from the carrier fit well to Higuchi and Korsmeyer‐Peppas models. Cell experiments indicate that the developed AMSN‐MTX‐HA displays high inhibitory effect on hepatoma (SMMC‐7721) cells while the drug‐free carrier of AMSN‐HA has good biocompatibility.

At present, chiral electroanalysis of nonelectroactive chiral compounds still remains a challenge because they cannot provide an electrochemical signal by themselves. Here, a strategy based on a competitive self-assembly interaction of a ferrocene (Fc) unit and the testing isomers entering into the cavity of β-cyclodextrin (β-CD) was carried out for chiral electroanalysis. First of all, the Fc derivative was directly bridged to silica microspheres, followed by inclusion into the cavity of β-CD. As expected, once it was modified onto the surface of a carbon working electrode as an electrochemical sensor, SiO2@Fc-CD-WE, its differential pulse voltammetry signal would markedly decrease compared with the uncovered Fc. Next, when l- and d-isomers of amino acids that included histidine, threonine, phenylalanine, and glutamic acid were examined using SiO2@Fc-CD-WE, it showed an enantioselective entry of amino acids into the cavity of β-cyclodextrin instead of Fc, resulting in the release of Fc with signal enhancement. For histidine, glutamic acid, and threonine, l-isomers showed a higher peak current response compared with d-isomers. The peak current ratios between l- and d-isomers were 2.88, 1.21, and 1.40, respectively. At the same time, the opposite phenomenon occurred for phenylalanine with a peak current ratio of 3.19 between d- and l-isomers. In summary, we are assured that the recognition strategy based on the supramolecular interaction can enlarge the detection range of chiral compounds by electrochemical analysis.

Amine hybrid silica aerogel globule (AHSAG) for CO2capture including direct air capture (DAC) was firstly synthesized via wet casting assisted self-catalyzed sol-gel process. AHSAG has abundant interpenetrating macropores, which favors diffusion of CO2into internal amine sites and can enhance CO2adsorption kinetics and capacity. The optimal CO2adsorption capacity of AHSAG with dry 100% and 400 ppm CO2are 3.82 (30 °C) and 1.86 mmol/g (55 °C), respectively. Corresponding amine efficiencies are 0.478 and 0.233. The effect of temperature on CO2adsorption capacity is attributed to simultaneous enhancement of mass transfer kinetics and adsorption thermodynamics. The highest CO2adsorption rate of AHSAG is achieved at 70 and 55 °C with 100% and 400 ppm CO2, respectively. The trend of CO2adsorption rate with temperature is attributed to the synergistic effect of diffusion kinetics and desorption. Based on experimental CO2adsorption kinetics, adsorption mechanism in 400 ppm CO2was estimated with different diffusion models. Both film diffusion resistance and intraparticle diffusion resistance are involved in CO2capture of AHSAG from air under given condition to control the overall adsorption process. Three kinetics models were used to fit the experimental data of AHSAG for DAC, and the Avrami model showed the best fitting within the whole adsorption period. Comparing with its state-of-the-art counterparts, AHSAG offers significant advantages for practical DAC, such as high adsorption capacity and amine efficiency, fast adsorption kinetics, and excellent cyclic stability.

A Prussian blue analogue is grown in situ on nickel foam (NF) by a co-precipitation strategy, which is further converted into Ni-Co tellurides ((Ni-Co)Te)/NiTe through a hydrothermal method. The obtained (Ni-Co)Te/NiTe shows a heterogeneous and multi-dimensional structure, which displays a high areal specific capacitance of 2390.7 mF cm−2at 1 mA cm−2and a high capacitance retention of 80.3 % after 5000 cycles. Further, a hybrid supercapacitor (HSC) is assembled by using the (Ni-Co)Te/NiTe grown on NF (NF@(Ni-Co)Te/NiTe) as the cathode and activated carbon (AC) supported on NF (NF@AC) as the anode, respectively. The HSC exhibits a maximum energy density of 95.6 Wh kg−1at the power density of 444.5 W kg−1, which is higher than most of the HSCs previously reported. The synergistic effect of the heterojunction in the (Ni-Co)Te/NiTe and its multi-dimensional structure plays a crucial role in the enhanced reaction kinetics of the HSC.

Over the last decades, the strategy of using stem cells has gained a lot of attention in treating many diseases. Recently, DR was identified as one of the common complications experienced by diabetic patients around the world. The current treatment strategy needs to be addressed since the active progression of DR may lead to permanent blindness. Interestingly, varieties of stem cells have emerged to optimize the therapeutic effects. It is also known that stem cells possess multilineage properties and are capable of differentiating, expanding in vitroand undergoing genetic modification. Moreover, modified stem cells have shown to be an ideal resource to prevent the degenerative disease and exhibit promising effects in conferring the migratory, anti-apoptotic, anti-inflammatory and provide better homing for cells into the damaged tissue or organ as well promoting healing properties. Therefore, the understanding of the functional properties of the stem cells may provide the comprehensive guidance to understand the manipulation of stem cells making them useful for long-term therapeutic applications. Hence in this review the potential use and current challenges of genetically modified stem cells to treat DR will be discussed along with its future perspectives.

This paper proposes a road intrusion detection model based on distributed optical fiber vibration sensors signals. Considering that the existing unsupervised classification method often has a high false alarm rate when meeting the new non-intrusion samples, we propose a one-dimensional semi-supervised generative adversarial network (1D-SSGAN) model for intrusion signal recognition. The 1D-SSGAN is composed of a generator and a discriminator. The output layer of the discriminator is mapped to N+1 classes, and the generator and discriminator are trained on the N class dataset. During the learning process of the generator against the discriminator, many new samples are generated based on a small number of samples, which effectively expands the datasets and assists the training of the discriminator. Experimental result analysis demonstrates the effectiveness of the proposed model.

Au–Ag nanoparticles (Au–Ag NPs) with a core–shell structure are prepared and used for ultrasensitive electrochemical impedance (EI) discrimination of the isomers of tryptophan (Trp). As revealed by circular dichroism, rotary polarization caused by the Au–Ag NPs is consistent with D-Trp but opposite to L-Trp, and thus, the Au–Ag NPs can selectively combine with D-Trp through preferential interactions. Compared with Au–Ag NPs, the composites of D-Trp and Au–Ag NPs (Au–Ag NPs/D-Trp) display significantly increased charge transfer resistance (Rct); differently, the Rctof Au–Ag NPs/L-Trp remains almost unchanged because the Au–Ag NPs exhibit poor affinity toward L-Trp. Therefore, ultrasensitive EI enantiodiscrimination of the isomers of Trp is realized even at an extremely low concentration of the Trp isomers (0.1 nM). In addition, it is successfully applied in the ultrasensitive determination of D-Trp at a low concentration level (0.1 nM∼10 μM).

In the past, various chiral isomers accompanied by electroactive units have been distinguished using electrochemical techniques, which can produce electrochemical signals by themselves. However, it is still difficult to use an electrochemical technique to detect nonelectroactive samples. To address this bottleneck, an electroactive chiral polymer (S,S)-p-CVB-Fc that contains one redox-active ferrocene unit was designed and synthesized in this study. The electroactive polymer can give electrochemical signals as an alternative to the tested chiral samples, regardless of whether the isomers have electroactive units. Then, it was fixed on the surface of a glassy carbon electrode as an electrochemical chiral sensor. When nonelectroactive amino acids including proline, threonine, and alanine were examined by the sensor, clear discrimination in the response of peak current could be observed toward l- and d-isomers at pH 6.5. The peak current ratios (IL/ID) for proline and alanine were 1.47 and 1.48, respectively. In contrast, for threonine, the d-isomer exhibited a higher peak current than the l-isomer with a ratio of 2.59. In summary, the results ensure that the current work can enlarge the testing scope of chiral samples in the field of chiral electroanalysis using an electroactive sensor.