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Background: Adults living alone represent a growing population group in China. Understanding the prevalence of body mass index (BMI) categories and their associations with demographic and lifestyle factors among this group is essential for informing targeted interventions and public health policies. Methods: In this population-based cross-sectional study, we used individual-level data from the 2011–2021 China General Social Survey. Main outcomes were prevalence of BMI categories adjusted for gender and age, using logistic regression and model-predicted marginal prevalence to estimate BMI categories prevalence. Results: We analyzed 9,077 single-living Chinese adult participants. The primary-adjusted prevalence of BMI categories varied across different genders and age groups. Underweight was more prevalent in females (12.73%; 95% CI: 12.31% - 13.14%) than in males (7.54%; 95% CI: 7.19% - 7.88%), while overweight and obesity were higher in males. Primary-adjusted underweight prevalence was highest among the 18–24 years age group (22.09%; 95% CI: 20.17% - 24.01%) and decreased with age. Primary-adjusted overweight prevalence increased with age, peaking in the 45–54 years age group (41.94%; 95% CI: 40.96% - 42.93%). Primary-adjusted obesity prevalence exhibited a fluctuating pattern across age groups, with the highest prevalence observed in the 45–54 years age group (9.81%; 95% CI: 9.19% - 10.44%). Conclusion: Our findings reveal significant associations between BMI categories and demographic and lifestyle factors among adults living alone in China. These results can inform targeted interventions and public health policies aimed at promoting healthy weight management and addressing the unique health challenges faced by single-living individuals in China. [ABSTRACT FROM AUTHOR]

[Display omitted] • P2-Na 0.7 Cu 0.2 Fe 0.2 Mn 0.5 Ti 0.1 O 2 cathode for SIB is prepared via Cu/Ti co-doping. • The optimized cathode exhibits a high reversible capacity and decent cycle life. • Alleviated phase transition and transition-metal dissolution underpin the enhancement. • The excellent crystal structure is maintained after exposure to air or in water. Environmentally friendly P2-type layered iron manganese oxides appear to be one of the most potential cathode materials for sodium-ion batteries (SIBs). However, their practical application is hindered by the unfavorable phase transitions, dissolution of transition metals, and poor air stability. One effective strategy by either single-cation doping or high-cost Li involved co-doping is used to alleviate the problems. Here, low-cost Cu/Ti co-doping is introduced to boost P2-Na 0.7 Cu 0.2 Fe 0.2 Mn 0.5 Ti 0.1 O 2 as an air and electrochemical stable cathode material for SIBs. The resulting electrode delivers an initial capacity of 130 mAh g−1 at 0.1C within 2.0–4.2 V, a reversible discharge capacity of 61.0 mAh g−1 at a high rate of 5C and a capacity retention ratio exceeding 71.1% after 300 cycles. In particular, the co-doped crystal structure is well-maintained after 1 month of exposure to air, and even 3 days of soaking in water. Furthermore, the enhancement is elucidated by the effectively mitigated P2–Z and the completely suppressed P2–P′2 phase transitions, the decreased volume variation proved by in-situ X-ray diffraction (XRD), as well as the lowered transition-metal dissolution evidenced by inductively coupled plasma optical emission spectrometer (ICP-OES) and X-ray photoelectron spectroscopy (XPS). The low-lost Cu/Ti doping strategy could thus be effective for designing and preparing environmentally friendly and high-performance cathode materials for SIBs. [ABSTRACT FROM AUTHOR]

Background: Particularly fine particulate matter (PM2.5) has become a significant public health concern in China due to its harmful effects on human health. This study aimed to examine the trends in all causes and cause specific morality burden attributable to PM2.5 pollution in China. Methods: We extracted data on all causes and cause specific mortality data attributable to PM2.5 exposure for the period 1990–2019 in China from the Global Burden of Disease 2019. The average annual percent change (AAPC) in age-standardized mortality rates (ASMR) and years of life lost (YLLs) due to PM2.5 exposure were calculated using the Joinpoint Regression Program. Using Pearson's correlation, we estimated association between burden trends, urban green space area, and higher education proportions. Results: During the period 1990–1999, there were increases in mortality rates for All causes (1.6%, 95% CI: 1.5% to 1.8%), Diabetes mellitus (5.2%, 95% CI: 4.9% to 5.5%), Encephalitis (3.1%, 95% CI: 2.6% to 3.5%), Ischemic heart disease (3.3%, 95% CI: 3% to 3.6%), and Tracheal, bronchus and lung cancer (5%, 95% CI: 4.7% to 5.2%). In the period 2010–2019, Diabetes mellitus still showed an increase in mortality rates, but at a lower rate with an AAPC of 1.2% (95% CI: 1% to 1.4%). Tracheal bronchus and lung cancer showed a smaller increase in this period, with an AAPC of 0.5% (95% CI: 0.3% to 0.6%). In terms of YLLs, the trends appear to be similar. Conclusion: Our findings highlight increasing trends in disease burden attributable to PM2.5 in China, particularly for diabetes mellitus, tracheal, bronchus, and lung cancer. [ABSTRACT FROM AUTHOR]

To comprehensively understand the volatile compounds and assess the aroma profiles of different types of Pyrus ussuriensis Maxim. Anli, Dongmili, Huagai, Jianbali, Jingbaili, Jinxiangshui, and Nanguoli were detected via headspace solid phase microextraction (HS-SPME) coupled with two-dimensional gas chromatography/time-of-flight mass spectrometry (GC×GC-TOFMS). The aroma composition, total aroma content, proportion and number of different aroma types, and the relative quantities of each compound were analyzed and evaluated. The results showed that 174 volatile aroma compounds were detected in various cultivars, mainly including esters, alcohols, aldehydes, and alkenes: Jinxiangshui had the highest total aroma content at 2825.59 ng/g; and Nanguoli had the highest number of aroma species detected at 108. The aroma composition and content varied among pear varieties, and the pears could be divided into three groups based on principal component analysis. Twenty-four kinds of aroma scents were detected; among them, fruit and aliphatic were the main fragrance types. The proportions of aroma types also varied among different varieties, visually and quantitatively displaying changes of the whole aroma of the different varieties of pears brought by the changes in aroma composition. This study contributes to further research on volatile compound analysis, and provides useful data for the improvement of fruit sensory quality and breeding work. [ABSTRACT FROM AUTHOR]

The existence of branch pipelines is very common in industry. And the angles between the pipes are different. For studying the influence of inclined crossed pipe and different equivalence ratios on the flame propagation dynamics of premixed methane/air, a high-velocity camera and pressure sensor were used to record the flame propagation images and the changes of pressure inside the pipe on the basis of experiments. The results show the maximum flame propagation velocity and the maximum overpressure increased with the increase of equivalent ratios. Since the crossover pipe was set up with three outlets, the obtained results showed the maximum overpressure value in the straight pipeline was higher than that in the cross pipeline, 0.1553 bar and 0.1142 bar, respectively. Nevertheless, the maximum flame propagation velocity in cross pipe was much higher than that in straight pipe, 65.6 m/s and 25.6 m/s, respectively. The existence of branch pipe can greatly improve the flame velocity. [ABSTRACT FROM AUTHOR]

We propose to use dielectric metasurface as a novel platform to generate dipole trap arrays with high quality and efficiency. According to the specific design parameters of the dipole trap array, the modulation phase and the focusing phase are calculated respectively. Building upon this, we design a metasurface device consisting of cylindrical TiO 2 -based integrated-resonant unit-cells by combining the modulating phase with the focusing phase. In addition, by finely adjusting the position of the nanopillar, a good match between the theoretical phase and the transmission phase of the nanopillar can be achieved to reduce the aberration introduced by the metasurface device. We conducted simulation experiments to demonstrate several configurations of dipole trap arrays. The results indicate that the obtained dipole trap arrays are precisely positioned and have uniform intensity distribution. The spacing and quantity of the traps obtained through this method can be controlled, providing a versatile and scalable system for neutral single-atom quantum information processing and quantum simulation. • By finely tuning the nanopillar position on the metasurface, we achieve a precise match between theoretical and transmission phases. • Combining modulation and focusing phases, our designed metasurface device replaces the function of both the SLM and strong focusing systems. • We use dielectric metasurface as a novel platform to generate dipole trap arrays for single-atom system with high quality and efficiency. [ABSTRACT FROM AUTHOR]

A novel bimetallic layered hydroxide (Ca–Fe–Cl LDHs) was prepared for the removal of arsenic (III) (As (III)) from an aqueous solution. The materials were characterized by SEM, XPS, TGA, and FTIR to analyze this removal mechanism. The effects of pH, contact time, dosage, initial concentration, and coexisting anions on the removal of As (III) by Ca–Fe–Cl LDHs were explored. The results demonstrated that Ca–Fe–Cl LDHs exhibited good performance with a maximum adsorption capacity of 22.1 mg/g, and adding 1.26 g/L Ca–Fe–Cl LDHs can reduce the concentration of arsenic solution (0.4 mg/L) to below 0.01 mg/L, and the removal rate of As (III) was not affected within the pH range of 2 − 12. The Langmuir model and the pseudo second-order dynamics model could better fit the experimental data with R2 equal to 0.969 and 0.885, respectively. Coexisting ions, such as HPO42−, SO42−, CO32−, and NO3−could inhibit material adsorption and reduce the removal efficiency of As (III). Under experimental conditions, the concentration of 0.01 M Na2CO3 solution was used for regeneration, and the efficiency of As (III) removal was maintained above 90% after 5 regenerations. [ABSTRACT FROM AUTHOR]

To predict the volume change of stage III NSCLC after radiotherapy with 60 Gy. This retrospective study included two independent cohorts, a train cohort of 192 patients, and a test cohort of 31 patients. We developed a radiomics model based on radiomics features and clinical variables. LIFEx package was used to extract radiomics texture features from CT images. The classification method was logistic regression analysis and feature selection was performed by correlation coefficients. Performance metrics of logistic regression include accuracy, precision, the receiver operating characteristic curves, and recall. The combination features of clinical variables and radiomics can predict the tumor volume change after radiotherapy with 88.7% accuracy (88.6% precision, 88.7% recall, and 88.7% ROC area). Radiomics features combined with medical knowledge have a great potential to predict accurately tumor volume change of stage III NSCLC after radiotherapy with 60 Gy. [ABSTRACT FROM AUTHOR]

Li 3 VO 4 is one of the most potential anode materials for high-performance lithium ions batteries due to its suitable voltage platform and considerable theoretical capacity. Nevertheless, unsatisfactory electronic conductivity is hindering its further practical application. In this study, we report the synthesis of oxygen vacancy-rich Li 3 VO 4 nanoplates via adjusting surface tension of reaction solution in the hydrothermal process. Decreasing the surface tension of reaction solution leads to a morphology change of Li 3 VO 4 from large block to nanoplate and then nanoparticles gradually, accompanied by the generation of oxygen vacancies. The optimal Li 3 VO 4 sample, consisting of two-dimensional nanoplates rich in oxygen vacancies, delivers a discharge specific capacity of 458 mAh g −1 at 0.1 A g −1 after 100 cycles. Even at a high current density of 1 A g −1, its capacity still reaches 235 mAh g −1 after 300 cycles, exhibiting outstanding cycling stability. The rich oxygen vacancies and two-dimensional nanoplate morphology synergistically accelerate lithium ions conduction and enhance the electrochemical performance of Li 3 VO 4. The strategy reported in this paper can be readily extended to a variety of alkali metal vanadium oxides, possibly expanding the exploration of other metal oxides in the two dimensions. [ABSTRACT FROM AUTHOR]

Realizing accurate pesticide multiresidue detection in a complex matrix is still a challenge for point-of-care sensing methods. Herein, we introduced background-free and multicolor aptasensors based on bioorthogonal surface-enhanced Raman scattering (SERS) tags and successfully applied them to analyze multiple pesticide residues. The excellent anti-interference and multiplex capability are due to the application of three bioorthogonal Raman reporters involving 4-ethenylbenzenamine (4-EBZM), Prussian blue (PB) and 2-amino-4-cyanopyridine (AMCP) with alkynyl and cyano groups, which demonstrated apparent Raman shift peaks at 1993 cm−1, 2160 cm−1, and 2264 cm−1 in the biologically Raman-silent region, respectively. Ultimately, a detection range of 1–50 nM for acetamiprid, atrazine and malathion was achieved with detection limits of 0.39, 0.57 and 0.16 nM, respectively. The developed aptasensors were successfully used to determine pesticide residues in real samples. These proposed multicolor aptasensors offer an effective strategy for pesticide multiresidue detection with advantages of anti-interference, high specificity and high sensitivity. [Display omitted] • Aptasensors for Pesticide Multi-residues detection Using Bioorthogonal SERS tags. • Bioorthogonal tags demonstrated Raman peaks at 1993, 2160 and 2264 cm−1. • Aptasensors showed LODs of 0.39, 0.57 and 0.16 nM for three pesticides respectively. • Aptasensors were efficiently applied to detect pesticide multi-residues in real samples. [ABSTRACT FROM AUTHOR]

• Electroencephalographic spatial features are used for emotion recognition. • Design automatic eigenvalue selection to improve the Common Spatial Pattern method. • A channel optimization strategy is proposed to decrease the computation load. • The proposed method achieves superior results than the traditional method. Emotional human-computer interaction (HCI) has become an important research area in the fields of artificial intelligence and cognitive science, owing to the requirement for active emotion perception. To enhance the performance of electroencephalography (EEG)-based emotional HCI, this paper proposes an improved common spatial pattern combined with a channel-selection strategy (ICSPCS) for EEG-based emotion recognition. Specifically, we first use a common spatial pattern algorithm to design a spatial domain filter according to three different emotions (positive, neutral, and negative). The traditional joint approximation diagonalization method using the criterion of the "highest score eigenvalue" may be unable to solve multiple classifications of emotion representation. Therefore, we design three different eigenvalue selection methods in terms of the positions of the eigenvalues with the highest scores. Finally, to make the installation easier and reduce the computational load, we also develop a channel-selection strategy based on the weight values that individually reflect the degrees of influence of all the channels on emotion recognition. Experiments are conducted on a self-collected dataset and on the MAHNOB-HCI dataset. The average recognition accuracies for the three emotion tasks are found to be 85.85% and 94.13% on the self-collected and MAHNOB-HCI datasets, respectively, thus proving the effectiveness of the proposed ICSPCS method for emotion recognition. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) can threaten the clean production of rice owing to continuous selective pressure in heavy metal–antibiotic co-contaminated paddy soils. As an important soil carbon reservoir, the role of humic substances from different types of manure in the regulation of soil ARGs remains unclear. In this study, fulvic acid (FA) and humic acid (HA) were extracted from pig manure (PM), cow dung (CD), and chicken manure (CM). The influence of their characteristics and doses on the fate of ARGs was investigated in arsenic (As)–antibiotic co-contaminated paddy soils. The release of As and degradation of antibiotics were promoted in 1% PM-FA treatment, with increases of 4.8%–5.6% and 8.3%–8.8% compared with CM-FA and CD-FA treatments, respectively. The coexistence of FA/HA, Fe, As, and antibiotics in soil pore water affected the environmental behavior of ARGs, with FA showing a more positive effect. Species including Bacillus , Geobacter , Desulfitobacterium , and Christensenellaceae_R-7_group were considered potential hosts of ARGs, and their resistance to co-contamination increased after the addition of FA. Membrane transport is a potential strategy for host bacteria of ARGs to cope with As–antibiotic complex pressure. These results demonstrate the coupling mechanisms of As, antibiotics, and ARGs regulated by different humic substances in co-contaminated paddy soils, which could support the clean production of rice in agricultural practice. [Display omitted] • The role of humic substances from different manure was studied on the fate of ARGs. • PM-FA has more aliphatic carbon and electron transfer ability than CD- and CM-FA. • PM-FA (1%) strongly regulated the biotic and abiotic processes of As-OTC in soil. • Resistance of ARGs host bacteria to As-OTC co-contamination increased with FA. • Membrane transport is the potential strategy to cope with As-OTC pressure in soil. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • UHPLC-Q-TOF-MS was used for the identification of flavonoid constituents in flowers of Juglans regia L. • Thirty-six flavonoid compounds were identified, among which some were reported in Juglans regia L. for the first time. • The mass spectrometric fragmentation pathways of eleven representative flavonoids were proposed. Abstract The flowers of Juglans regia L. have demonstrated their medicinal value as a part of edible plants. In this study, an analytical methodology for identification of flavonoid chemical constituents in flowers of Juglans regia L. was established using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Thirty-six flavonoid compounds were identified based on highly accurate mass measurements, and the mass spectrometric fragmentation pathways of eleven representative compounds were proposed, which was helpful for the identification of different types of flavonoids. The study has laid the foundation for the research and development of effective drugs from flowers of Juglans regia L. [ABSTRACT FROM AUTHOR]

The authors describe an ultra-sensitive approach for the determination of lead(II) by using a lead-specific aptamer and a fluorophore derived from perylenetetracarboxylic acid diimide (PTCDI). The fluorescence of PTCDI, with excitation/emission peaks at 494/543 nm, is quenched by the aptamer but restored if the aptamer binds lead(II). A detection scheme has been worked out that has a 0.1 ng·mLlimit of detection and a dynamic range that extends from 0.1 ng·mL to 10 μg·mL. The assay also demonstrates high selectivity for lead ions over nine other ions due to the aptamer's high specificity. The method shows a average recovery of 77.2-93.4% with an RSD of less than 3% in water samples. [ABSTRACT FROM AUTHOR]

Background: ambient fine particulate air pollution (PM2.5) is an important yet often overlooked risk factor for cardiovascular disease in the United States. However, epidemiologic evidence suggests that current knowledge does not comprehensively capture state-level disparities in mortality for ambient PM2.5-related ischemic heart diseases. I performed serial cross sectional analysis with ambient PM2.5-attributable ischemic heart diseases decedents between 1990 and 2019. I used the Global Health Data Exchange to extract age adjusted mortality rates in each state, and used Joinpoint software to calculate average annual percentage change. Results: the average age adjusted mortality rates (AAMR) for ischemic heart diseases attributable to ambient PM2.5 for both sex ranged from 1.5 (1.3–1.8) per 100,000 in Hawaii to 1.1 (0.9–1.3) per 100,000 in Mississippi, respectively. The rate of change in AAMR varied widely across states. Compared with the national level, the number of states with smaller decline has increased from 3 before 2002 to 10 after 2011. Oregon, Idaho, and Montana showed an upward trend in AAMR, which was independent of sex after 2011. Between 1990 and 2019, average AAMR for ischemic heart diseases attributable to ambient PM2.5 was higher for male than female in all states. But the number of states with sex disparities in the rate of change has decreased, from 13 in 1990–2002 to 5 after 2011. Conclusions: wide state-level disparities exist in burden of ischemic heart diseases attributable to ambient PM2.5. After 2011, the association between rate of AAMR decline and sex weakened across states. State-level policies and programs are needed to address the avoidable burden of ischemic heart diseases deaths attributable to ambient particulate pollution, with priority for states with a higher burden. [Display omitted] • Oregon, Idaho, and Montana saw an upward trend in age adjusted mortality rates. • Female in the District of Columbia, Kansas, and Texas saw greater declines than male after 2011. • The rate of decline in age adjusted mortality rates in three states was below the national level. [ABSTRACT FROM AUTHOR]

The co-existence of antibiotics and heavy metals in soil with manure application poses high risk to both environment and human health, and thus effective remediation methods are in urgent need. This study investigated the synergistic effects of electrokinetic remediation (EKR) on antibiotic resistance and arsenic (As) in co-contaminated paddy soils. EKR treatments in soil amended with pig manure (EKR-PD) showed better remediation efficiency compared with that without pig manure. In detail, the content of available As and the abundance of antibiotic-resistant bacteria (ARB) decreased by 25.2 %−41.4 % and 9.5 %−21.1 % after 7-d remediation, respectively, due to a relatively higher current density for EKR-PD. The role of the electric field contributed to 33.9 % of antibiotic degradation. Antibiotic resistance genes (ARGs) with ribosomal-protection and enzymatic-deactivation types were easier to remove, with the removal ratio of 37.8 %−41.6 % in EKR-PD. Brevundimonas was the most significantly different species during remediation. Bacillus and Clostridium_ sensu_stricto_1 were potential host bacteria of ARGs in the electric field. Membrane transport might be an effective strategy for microorganisms to respond to the stress of both electric field and co-contaminated environments. This study supports the potential role of EKR in the co-contamination of heavy metals and antibiotic resistance under manure application. [Display omitted] • Manure application enhanced the resistance of soil microbes to the electric field. • Higher removal of antibiotics-arsenic occurred in manure-applied EKR. • Brevundimonas was the most significantly different species among treatments. • Potential ARGs host bacteria were judged in the OTC-As soil during EKR. • Membrane transport related with resistance to OTC-As and electric field. [ABSTRACT FROM AUTHOR]

Background: Glycyrrhetinic acid (GA) derivatives had shown not only cytotoxicity but also could trigger apoptosis in various human cancer cell lines. Moreover, cinnamic acid (CA) and its phenolic analogues as potent antitumor agents were employed in the design of anti-tumor drugs. To further improve the anti-tumor activity of GA and CA derivatives, a series of novel compounds were designed and synthesized using GA and CA derivatives fragments. Results: The result showed that all the novel glycyrrhetinic acid-cinnamoyl (GA-CA) hybrids presented higher antitumor activity on the tumor cell lines of HepG2, HT-29, Hela and lower cytotoxicity on three non-tumor cells lines MDCK, HY926, H9C2 than the parent compounds (IC > 50 μM). It was worth noting that 8a had a superior cytotoxicity effect on Hela cells (IC = 8.54 μM) than on other cancer cell lines (IC > 15 μM). And it also indicated that 8a showed lower cytotoxicity (IC > 27 μM) towards MDCK, HY926 and H9C2 cells than cisplatin (DDP, IC < 10 μM). Moreover, according to the acute toxicity, it could be indicated that the LD of 8a exceeded 3.0 g/kg by oral administration in mice. The further research using Giemsa, H33342 staining, flow cytometric analysis and caspase-3 assay showed that 8a could cause Hela cell damage, nuclei lysis and apoptosis. In addition, the structure-activity relationships of these hybrids were briefly discussed. Conclusions: Compared with GA, target compounds demonstrated better anti-tumor activity, among which 8a was the most active one. What's more, structure-activity relationship analysis also revealed that hybrids with trans olefinic bond group show higher antitumor activity than those without olefinic bond, such as 1a > 1b, 6a > 2b, 8a > 3b, 9a > 4b. In addition, it was found that the methoxy substituent might enhance selectivity of GA-CA hybrids towards regular non-cancerous cells MDCK, HY926 and H9C2, such as 4a, 6a, 7a, 8a. However, there might be less relationship between the cytotoxicity and the quantity, position of methoxy moiety. Hence, it is urgent need to synthesize efficient, low toxicity and multi-target anti-tumor compounds based on the structure combination principle. [ABSTRACT FROM AUTHOR]

Most aptasensors are designed based on aptamers' conformational change or structural transformation upon interaction with their targets. A limitation of these strategies is the unpredictability of such structural alterations that may yield false-positive or nonspecific signals. In bioanalysis, a dominant strategy for protein determination is the sandwich assay because of its high specificity and sensitivity resulting from the dual recognition mechanism. However, the approach is poorly suited to detection of low molecular weight targets, which unlikely bind to two aptamers simultaneously due to steric hindrance. To circumvent this drawback, a split aptamer strategy was recently developed, in which nucleic acid aptamers were split into two fragments that could specifically form a ternary assembly in the presence of ligand. This elegant approach has been extensively adopted for detection of various targets, especially small molecular weight targets, with different transduction methods including colorimetric, fluorescence, and electrochemical techniques. This review first introduced split aptamers and how to obtain split aptamers, and then summarized recent advances in the development of sandwich-format biosensing assays based on split aptamer fragments, aiming at providing a general guide for the design of split-aptamer-based sandwich assays. Furthermore, we discussed possible challenges in the development of split-aptamer-based sandwich assay regarding stability, sensitivity and multiplicity, so as to offer future opportunities of this assay. [ABSTRACT FROM AUTHOR]

Compared with conventional antibody-based immunoassay methods, aptasensors based on nucleic acid aptamer have made at least two significant breakthroughs. One is that aptamers are more easily used for developing various simple and rapid homogeneous detection methods by “sample in signal out” without multi-step washing. The other is that aptamers are more easily employed for developing highly sensitive detection methods by using various nucleic acid-based signal amplification approaches. As many substances playing regulatory roles in physiology or pathology exist at an extremely low concentration and many chemical contaminants occur in trace amounts in food or environment, aptasensors for signal amplification contribute greatly to detection of such targets. Among the signal amplification approaches in highly sensitive aptasensors, the nuclease-based target recycling signal amplification has recently become a research focus because it shows easy design, simple operation, and rapid reaction and can be easily developed for homogenous assay. In this review, we summarized recent advances in the development of various nuclease-based target recycling signal amplification with the aim to provide a general guide for the design of aptamer-based ultrasensitive biosensing assays. [ABSTRACT FROM AUTHOR]

Experimental and dynamic analyses of the deflagration characteristics of laminar premixed syngas-air at different preheating temperatures and with different CO 2 volume fractions were carried out in a rectangular half-open pipe. The effects of CO 2 concentration and different initial temperatures on the flame structure evolution, flame structure profile and reaction rate of critical radicals, flame propagation speed, overpressure dynamics and hydrodynamic instability of syngas-air mixture were studied. The FFCM-1 mechanism was used to predict the laminar burning velocity of syngas-air under relevant conditions. The results revealed that the addition of CO 2 inhibited the flame propagation and reduced the concentration of H, OH and O, thus reduced the laminar burning velocity. The increase in temperature promotes the chemical effect of CO 2 , and the interaction between the flame front and the pressure wave is more pronounced, prolonging the duration of the " tulip " flame. Adding CO 2 reduces the flame front speed and overpressure, decreases the oscillation amplitude in late flame propagation, and inhibits the explosion intensity. Meanwhile, the temperature increase accelerates the flame propagation in the spherical and finger stages, and the maximum flame propagation speed and peak pressure appear earlier. In addition, as CO 2 content and temperature rise, flame hydrodynamic instability is difficult to ignore. However, there is a lack of data from studies of syngas deflagration dynamics at higher temperatures and with higher CO 2 additions. This suggests a focus on studies at higher temperatures as well as with higher CO 2 additions to enable the development of accurate kinetic models for wide range of syngas combustion. Also, the higher the initial temperature, the longer the time required for heating. • The appearance time of the tulip flame increased with the initial temperature. • CO 2 inhibits flame propagation and reduces the concentration of H, OH and O. • The maximum flame front speed appear earlier as the initial temperature increases. • The peak pressure decreases with increasing initial temperature. [ABSTRACT FROM AUTHOR]

Layered transition-metal oxides have been potential as high-performance cathode materials for sodium-ion batteries (SIBs), however, suffer from the undesirable side reactions between cathode/electrolyte interface during cycling. One improvement strategy by surface coatings is typically used, but at the compromise of lowering ion transport kinetics and poor rate capability. Herein, we report a surface optimized high-rate P2-Na 2/3 Ni 1/3 Mn 2/3 O 2 cathode material for SIBs via a highly conductive Al-doped ZnO (AZO). By tuning the calcination temperatures, the optimized cathode material coated with 1 wt% AZO at 500 °C exhibits decent cycling and rate performances (66.2 mAh g−1 with a capacity retention of 82.6% at 5C after 500 cycles). Electrochemical kinetics analysis demonstrates that the NM@AZO-500 exhibits a high Na+ diffusion coefficient and a low charge-transfer resistance, and in-situ X-ray diffraction (XRD) and ex-situ X-ray photoelectron spectroscopy (XPS) reveal that the AZO coating effectively relieves the lattice stress during cycles and inhibits undesirable side reaction; all of which give rise to the observed enhancement. The result promises an effective surface optimized route for high-performance cathode materials for SIBs by coating highly conductive oxide. [Display omitted] [ABSTRACT FROM AUTHOR]

Traffic sign detection is an important part of environment-aware technology and has great potential in the field of intelligent transportation. In recent years, deep learning has been widely used in the field of traffic sign detection, achieving excellent performance. Due to the complex traffic environment, recognizing and detecting traffic signs is still a challenging project. In this paper, a model with global feature extraction capabilities and a multi-branch lightweight detection head is proposed to increase the detection accuracy of small traffic signs. First, a global feature extraction module is proposed to enhance the ability of extracting features and capturing the correlation within the features through self-attention mechanism. Second, a new, lightweight parallel decoupled detection head is proposed to suppress redundant features and separate the output of the regression task from the classification task. Finally, we employ a series of data enhancements to enrich the context of the dataset and improve the robustness of the network. We conducted a large number of experiments to verify the effectiveness of the proposed algorithm. The accuracy of the proposed algorithm is 86.3%, the recall is 82.1%, the mAP@0.5 is 86.5% and the mAP@0.5:0.95 is 65.6% in TT100K dataset, while the number of frames transmitted per second is stable at 73, which meets the requirement of real-time detection. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is a powerful and high-speed detection technology. It provides information on molecular fingerprint recognition with ultrahigh sensitive detection. However, it shows poor anti-interference capacity against complex matrices. Molecularly imprinted polymers (MIPs) can achieve specific recognition of targets from complex matrices. Through introducing the MIP separation system, the MIP-SERS chemical sensor can effectively overcome the limitation of complex matrix interference, and further improve the stability of sensors for detection. Herein, the materials and structures of integrated MIP-SERS sensors are systematically reviewed, and its application as a sensor for chemical detection of hazardous substances in environmental and food samples has been addressed as well. To broaden the prospects of application, we have discussed the current challenges and future perspectives that would accelerate the development of versatile MIP-SERS chemical sensors. Image 1 • A refining of major scientific developments of SERS for advancing chemical analyzing. • Introducing molecular imprinting for addressing matrix interference. • Introduction to the development and classification of MIP-SERS chemical sensors. • Various applications of MIP-SERS sensors in environmental and food samples. • Future prospects of MIP-SERS detection methods. [ABSTRACT FROM AUTHOR]

A tungsten selenide (WSe 2) nanofilm was successfully prepared by liquid phase exfoliation. Open and closed aperture Z-scan techniques were used to distinguish between the real and imaginary parts of the third-order optical nonlinearity of the WSe 2 nanofilm at 800 nm. The WSe 2 nanofilm exhibits excellent saturable absorption characteristics at this waveband. A saturation light intensity of 147 ± 9 GW/cm2, a modulation depth of 24% and a nonlinear refractive index coefficient of about −1.36 × 10−10 cm2/W were obtained. The results reveal that the WSe 2 nanofilm is an excellent third order nonlinear optical material, and has potential applications ranging from ultrashort pulse laser mode-locking to optical Kerr-based photonic devices in the 800 nm wavelength range. Image 1 • Tungsten selenide (WSe 2) nanofilm was successfully prepared by liquid phase exfoliation method. • The saturable absorption characteristics and the nonlinear refractive index at 800nm for the nanofilm were obtained. • WSe 2 nanofilm was proved to be an excellent nonlinear material and has potential application as a modulator at 800nm. [ABSTRACT FROM AUTHOR]

• DOM characteristics influence As methylation and biovolatilization in paddy soils. • Arsine production is markedly enhanced following pig manure DOM application. • Among DOMs, Pig manure DOM addition yields much higher As-methylation in paddy soil. • Pig manure DOM addition increases the OTU number of arsM -carrying bacteria. • High labile C amount is responsible for the enhanced As-methylation in paddy soils. The effect of dissolved organic matter (DOM), derived from composted pig manure or rice straw, on arsenic methylation and subsequent biovolatilization in paddy soils was investigated. Arsine production following pig manure DOM application was 2.7- and 9.6-fold higher than that of soils treated with rice straw DOM and the control, respectively. Trimethylarsine was the dominant arsine at 54 %, followed by dimethylarsine at 22 %, arsine at 21 %, and monomethylarsine at 3 %. The copy numbers of the total and As-methylating bacteria were significantly enhanced in paddy soils treated with DOM. Pig manure DOM altered soil bacterial profile by increasing the OTU number of As methylation-inducing bacteria, such as Proteobacteria, Bacteroidetes, Geobacter , Sphingomonas , Streptomyces , and Rhodopseudomonas , thereby promoting As volatilization and methylation in paddy soils. The higher relative content of alkyl-C, N-alkyl C, and carboxyl-C in pig manure DOM was responsible for the increase in total and arsM -carrying bacteria in paddy soils, leading to enhanced As methylation. These observations will promote a better understanding of the role of DOM in mediating As methylation and volatilization, along with how organic fertilization affects straighthead disorder of rice, a condition caused by methylated arsenic species. [ABSTRACT FROM AUTHOR]

Chalcogenide glasses with less optical losses are highly demanded as optical materials for micro lense, waveguide and fiber devices. However, it is still challengeable to reduce the optical losses in infrared chalcogenide glasses with opaque visible light. Herein, an improved 3D distribution of scattering sources is established in this study to test and compare the concentration and distribution of defects in As 38 S 62 , Ge 28 Sb 12 Se 60 and As 40 Se 60 chalcogenide glasses. Furthermore, by comparing the scattering images of serial As 40 Se 60 glass prepared under various melting, quenching and annealing temperatures, the preparation process was optimized to reduce its scattering loss. In addition, this study introduced a scheme that could be widely applied to optimize processing of other infrared glasses and devices glass to reduce their scattering losses. [ABSTRACT FROM AUTHOR]

The published version of this article, unfortunately, contains error. Author name was corrected as "A. M. Abd EI-Aty" - upper case of "i" in "EI-Aty", instead of "A. M. Abd El-Aty" - lower case of "L". Given in this paper is the correct author name. [ABSTRACT FROM AUTHOR]

A class-specific molecular imprinted polymer (MIP) is described for simultaneous recognition of prometryn and simetryn prior to their determination via a fingerprint signal (at 974 cm−1 and 1074 cm−1) in the surface enhanced Raman scattering (SERS) spectra that were acquired in the presence of gold nanoparticles. The imprinted nanoparticles were applied to the analysis of rice and wheat samples spiked with both herbicides. The method has fairly good recoveries (72.7-90.9%) with a relative standard deviation of 1.7-7.8%, and a 20 μg·kg−1 limit of detection. The imprint factors (compared to non-imprinted polymers) are 5.3 for prometryn and 4.2 for simetryn (both at 10 μg·mL−1 of the initial solution).A MIP-SERS method was developed for simultaneous detection of triazine herbicides (prometryn and simetryn) in food samples. [ABSTRACT FROM AUTHOR]

Ammonia allows for long-distance and large-scale storage transport of renewable energy sources. The reactivity of NH 3 -Air flame can be enhanced by doping with hydrogen and by increasing the initial temperature. The flame combustion characteristics of NH 3 –H 2 -Air are studied in a rectangular closed pipe with a mole fraction of 45% H 2 , an equivalence ratio (φ) of 0.8–1.2 and 0.1 MPa. The initial temperatures (T u) of the mixture are 300 K, 375 K and 450 K. Experimental studies of flame front speed, flame tip structure evolution, and overpressure dynamics are performed. Laminar burning velocity (S L), peak mole fraction of key radicals, and flame instability of NH 3 –H 2 -Air flames are simulated in Chemkin Pro-software using the Mathieu and Petersen mechanism. The results show that the relatively low equivalence ratio and initial temperature promote the structural changes of the flame tip, forming a "tulip" flame and a distorted "tulip". As the equivalence ratio increases, the flame front speed and overpressure increase and the flame oscillates slightly. The distortion in the lip of the "tulip" is more pronounced. The increase in temperature promotes flame propagation in the early stages and the pressure decreases. Reactive activity increases with increasing temperature, the peak mole fraction of NH 2 and H radicals increases, and S L increases. At normal temperature, the flame is affected by thermo-diffusive instability only when lean mixture. The Darrieus-Landau instability increases as the equivalence ratio increases. Conversely, the Darrieus-Landau instability decreases with increasing temperature. Therefore, the current experimental and simulation results help to understand the laminar combustion characteristics of NH 3 –H 2 -Air at high temperatures. • The distortion of "tulip" is most obvious at T u = 300 K and φ = 1.1. • Increased temperature promotes flame propagation in the finger-shaped phase. • As The temperature increases (300–450 K), the H and NH 2 mole fractions increase. • DL instability decreases with increasing initial gas temperature. [ABSTRACT FROM AUTHOR]

Ammonia is a kind of carbonless alternative fuel with great research foresight. Improving the burning velocity of NH 3 and studying the reduce of nitrogen oxides have far-reaching significance for the effective utilization of ammonia. This paper mainly studies the characteristics of three different mixtures (NH 3 :H 2 = 1:1, NH 3 :H 2 :CO = 2:1:1, NH 3 :CO = 1:1) in closed tubes under different equivalent ratios of Ф (0.7–1.4), and use chemkin software to simulate the laminar burning velocity under different experimental conditions and at high temperature (298–650 K) and high pressure (1–10 at m), which carry out kinetic analysis and the related exploration of its nitrogen oxide emissions. The results show as follows: (1) In the closed pipe, the flame propagation speed of NH 3 /H 2 /air is the largest, when the equivalent ratio is 1.1, the flame propagation speed of three different mixtures is the highest, the overpressure phenomenon is the most obvious. and the overpressure and temperature are the highest in the pipe. (2) The symmetrical shape of the pipe changes the direction of the flame flow, creating an interesting turbulent flow that resembles a halberd. (3) Replacing half NH 3 fuel of NH 3 /air mixture with H 2 is mainly due to the chemical effect of H 2 leading to the increase of LBV, while replacing half NH 3 fuel of NH 3 /air mixture with CO is mainly due to the thermal effect leading to the increase of LBV. The promotion effect of elevated temperature is mainly due to the contribution thermal effect and chemical effect. For NH 3 /H 2 /air, chemical effect is the main component of promotion effect of elevated temperature. For NH 3 /CO/air mixture, the promotion effect of elevated temperature, which is more the influence of thermal effect. The inhibitory effect of initial pressure is the contribution of chemical effect. (4) High temperature promoted the formation of NO, while high pressure inhibited it. • The combustion characteristics of NH 3 /H 2 /air, NH 3 /CO/air, NH 3 /H 2 /CO/air in a closed pipe are discussed. • The shape of the pipe changes the direction of flame flow and forms an interesting phenomenon. • The different temperature compensation methods are used. • The kinetic analysis of elevated temperature and pressure. [ABSTRACT FROM AUTHOR]

Food safety is a critical issue that is closely related to people's health and safety. As a simple, rapid, and sensitive detection technique, surface-enhanced Raman scattering (SERS) technology has significant potential for food safety detection. Recently, researchers have shown a growing interest in utilizing silent region molecules for SERS analysis. These molecules exhibit significant Raman scattering peaks in the cellular Raman silent region between 1800 and 2800 cm−1 avoiding overlapping with the SERS spectrum of biological matrices in the range 600–1800 cm−1, which could effectively circumvent matrix effects and improve the SERS accuracy. In this review, the application of silent region molecules-based SERS analytical technique for food safety detection is introduced, detection strategies including label-free detection and labeled detection are discussed, and recent applications of SERS analysis technology based on molecules containing alkyne and nitrile groups, as well as Prussian blue (PB) in the detection of pesticides, mycotoxins, metal ions, and foodborne pathogens are highlighted. This review aims to draw the attention to the silent region molecules-based SERS analytical technique and to provide theoretical support for its further applications in food safety detection. [ABSTRACT FROM AUTHOR]

Located along the southern part of the West Qinling orogenic belt, the Yangshan gold deposit is one of the largest in China. The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite‐gold quartz veins. Pyrite and arsenopyrite are the major Au‐bearing minerals. Hydrothermal muscovite from gold‐bearing quartz veins was dated using the in situ Rb‐Sr method to determine the formation age of the Yangshan gold deposit. The Rb‐Sr isochron date of the muscovite yielded 210.1 ± 5.6 Ma (MSWD = 1.2). This date is near the lower end of the period of the mineralized granitic dykes (210.49–213.10 Ma). Two stages of gold enriching process are recognized in the gold‐bearing pyrite: the first is incorporated with the Co, Cu, As, Ni enrichment; and the second is accompanied by Bi, Co, Ni, Pb, Cu, Sb concentration. The in‐situ sulfur isotopic values of pyrites show a restricted Δ34s range of –1.43 ‰ to 2.86 ‰ with a mean value of 0.43 ‰. Trace‐element mapping and in‐situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary bedrock. Thus, magmatism plays a critical role in the formation of the Yangshan gold deposit. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract FDA approval of CpG oligodeoxynucleotide (CpG ODN) adjuvants for a human hepatitis B virus vaccine has been delayed until late 2017 because of concerns regarding the severe side effects, which may be attributed to the high dosage and systemic diffusion of this proinflammatory material. Considering that PLGA could provide shelter to resist nucleases in tissue and that cationic lipids could confine anionic oligonucleotides in the nanoparticles via electrostatic attraction to avoid systemic diffusion, we encapsulated a natural phosphodiester or the expensive phosphorothioate CpG ODNs in our previously reported hyaluronic acid-modified cationic lipid-PLGA hybrid nanoparticles and evaluated vaccine efficacy in a TC-1-grafted mouse model. Our results showed that together with Poly I:C, CpG ODN could promote the maturation of bone marrow-derived dendritic cells and the cross-presentation of exogenous antigens in vitro. For the coencapsulation with Poly I:C, in vivo studies showed that adjuvant effects on the vaccine efficacy of tumor depression, immune cell activation, and memory T-cell elevation of phosphodiester CpG ODNs were comparable to those of the phosphorothioate CpG ODNs at a low concentration (5 µg/dose). In conclusion, the combination of oligonucleotide adjuvants and synthetic particulate systems not only potentiated the immunogenicity of these nanoparticles but also made these adjuvants safer and more economical, which may be helpful for their wide application. [ABSTRACT FROM AUTHOR]

The effects of different initial temperatures (T = 300–500 K) and different hydrogen volume fractions (5%–20%) on the combustion characteristics of premixed syngas/air flames in rectangular tubes were investigated experimentally. A high-speed camera and pressure sensor were used to obtain flame propagation images and overpressure dynamics. The CHEMKIN-PRO model and GRI Mech 3.0 mechanism were used for simulation. The results show that the flame propagation speed increases with the initial temperature before the flame touches the wall, while the opposite is true after the flame touches the wall. The increase in initial temperature leads to the increase in overpressure rise rate in the early flame propagation process, but the peak overpressure is reduced. The laminar burning velocity (LBV) and adiabatic flame temperature (AFT) increase with increasing initial temperature. The increase in initial temperature makes the peaks of H, O, and OH radicals increase. • The flame propagation time increases with the initial temperature. • The increase of initial temperature leads to faster propagation of early flame. • The peak overpressure decreases with increasing initial temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVDF nanofiber membrane modified by haloamine salt has 99% antibacterial properties against E. coli and S. aureus. • The multi-scale PVDF-PAA-TMP-Cl nanofiber films were successfully prepared by depositing ultra-fine (20–35 nm) nanofiber layers on the surface of antibacterial scaffold fiber films. • After optimizing performance parameters, the multi-scale nanofiber member has excellent filtration efficiency (99.93 %) and low filtration resistance (79pa) for PM 0.3 and the antibacterial properties of E. coli and S. aureus were still above 90 % after 10 cycles of chlorination. • The preparation of multi-scale nanofiber membrane with high efficiency filtration and lasting antibacterial activity provides a new idea for the research of air and water filtration and protective materials. Particulate matter (PM) pollution and the coronavirus (COVID-19) pandemic have increased demand for protective masks. However, typical protective masks only intercept particles and produce peculiar odors if worn for extended periods owing to bacterial growth. Therefore, new protective materials with good filtration and antibacterial capabilities are required. In this study, we prepared multi-scale polyvinylidene fluoride (PVDF) nanofibrous membranes for efficient filtration and durable antibacterial properties via N -halamine modification. The N -halamine-modified nanofibrous membrane (PVDF-PAA-TMP-Cl) had sufficient active chlorine content (800 ppm), and the tensile stress and strain were improved compared with the original membrane, from 6.282 to 9.435 MPa and from 51.3 % to 56.4 %, respectively. To further improve the interception efficiency, ultrafine nanofibers (20–35 nm) were spun on PVDF-PAA-TMP-Cl nanofibrous membranes, and multi-scale PVDF-PAA-TMP-Cl nanofibrous membranes were prepared. These membranes exhibited good PM 0.3 interception (99.93 %), low air resistance (79 Pa), promising long-term PM 2.5 purification ability, and high bactericidal efficiency (>98 %). After ten chlorination cycles, the antibacterial efficiency against Escherichia coli and Staphylococcus aureus exceeded 90 %; hence, the material demonstrated highly efficient filtration and repeatable antibacterial properties. The results of this study have implications for the development of air and water filtration systems and multi-functional protective materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVDF nanofiber membrane modified by haloamine salt has 99% antibacterial properties against E. coli and S. aureus. • The multi-scale PVDF-PAA-TMP-Cl nanofiber films were successfully prepared by depositing ultra-fine (20–35 nm) nanofiber layers on the surface of antibacterial scaffold fiber films. • After optimizing performance parameters, the multi-scale nanofiber member has excellent filtration efficiency (99.93 %) and low filtration resistance (79pa) for PM 0.3 and the antibacterial properties of E. coli and S. aureus were still above 90 % after 10 cycles of chlorination. • The preparation of multi-scale nanofiber membrane with high efficiency filtration and lasting antibacterial activity provides a new idea for the research of air and water filtration and protective materials. Particulate matter (PM) pollution and the coronavirus (COVID-19) pandemic have increased demand for protective masks. However, typical protective masks only intercept particles and produce peculiar odors if worn for extended periods owing to bacterial growth. Therefore, new protective materials with good filtration and antibacterial capabilities are required. In this study, we prepared multi-scale polyvinylidene fluoride (PVDF) nanofibrous membranes for efficient filtration and durable antibacterial properties via N -halamine modification. The N -halamine-modified nanofibrous membrane (PVDF-PAA-TMP-Cl) had sufficient active chlorine content (800 ppm), and the tensile stress and strain were improved compared with the original membrane, from 6.282 to 9.435 MPa and from 51.3 % to 56.4 %, respectively. To further improve the interception efficiency, ultrafine nanofibers (20–35 nm) were spun on PVDF-PAA-TMP-Cl nanofibrous membranes, and multi-scale PVDF-PAA-TMP-Cl nanofibrous membranes were prepared. These membranes exhibited good PM 0.3 interception (99.93 %), low air resistance (79 Pa), promising long-term PM 2.5 purification ability, and high bactericidal efficiency (>98 %). After ten chlorination cycles, the antibacterial efficiency against Escherichia coli and Staphylococcus aureus exceeded 90 %; hence, the material demonstrated highly efficient filtration and repeatable antibacterial properties. The results of this study have implications for the development of air and water filtration systems and multi-functional protective materials. [ABSTRACT FROM AUTHOR]

[Display omitted] Advanced thermal-insulation materials for human use in high-temperature and ultra-low-temperature environments have received extensive attention. However, facile synthesis of aerogels with excellent mechanical and thermal properties via freeze-drying or electrospinning alone is still challenging. We hypothesized that a polyimide aerogel with high mechanical strength and good thermal-insulation performance and suitability for various applications at high and low temperatures could be prepared facilely using a simple and novel preparation strategy that combines electrospinning, freeze-drying, and in situ thermal crosslinking. Polyamideimide (PAI) nanofibers loaded with bismaleimide (BMI) were electrospun and dispersed into a polyamic acid aqueous solution. PAI/BMI-nanofiber-reinforced polyimide (IBNR-PI) aerogels with an interpenetrating network structure were prepared by freeze-drying and heat treatment. The IBNR-PI aerogels possessed extremely low volume density (26 mg cm−3) and high porosity (94.92%). Most importantly, they showed high tensile strength and good compressive fatigue resistance with plastic deformation of only 7% after 1000 compression cycles. The aerogels also showed a significantly low thermal conductivity (30.06 mW m−1 K−1) and excellent thermal insulation over a wide temperature range. Thus, the IBNR-PI aerogels are excellent candidates for thermal-insulation materials at high and low temperatures. [ABSTRACT FROM AUTHOR]

Transition-metal layered oxides (such as P2-Na2/3Ni1/3Mn2/3O2) are suggested as one type of the most potential cathode candidates for sodium ion batteries (SIBs) owing to their high capacity and low cost; however, they suffer from the structural damage and sluggish Na+ kinetics resulting from the undesirable phase transformation of P2−O2 and the Na+/vacancy ordering, respectively. Herein, a Mg/Ti co-doped P2-Na0.67Ni0.28Mg0.05Mn0.62Ti0.05O2 layered oxide is demonstrated as a high-efficiency cathode material for SIBs. The cathode delivers a high reversible capacity of 135.5 mAh g−1, good cycling stability (82.7 mAh g−1 upon 100 cycles at 0.1C), and an attractive energy density of 479.4 Wh Kg−1. Furthermore, the phase transition from the undesirable P2−O2 to the reversible P2−OP4 demonstrated by in situ XRD and the partially suppressed Na+/vacancy ordering as well as the improved electronic and ionic conductivities all give rise to the enhancement. These results show the important role of cationic co-doping in designing and preparing high-efficiency layered oxide cathode materials for SIBs. [ABSTRACT FROM AUTHOR]

In the propagation phase of a dielectric metasurface, there are two important problems. Firstly, the range of transmittance of the nanopillars for a building metasurface is usually between 60% and 100%, which reduces the metasurface's overall transmittance and affects the uniformity of the transmitted light. Secondly, the realistic phase provided by the nanopillar cannot be matched very well with the theoretical phase at each lattice location.The phase difference (between a realistic phase and theoretical phase) may reach tens of degrees. Here, we propose an interesting method to solve these problems. With this new method, a metalens is designed in this paper. The nanopillars for building the metalens have transmittance over 0.95, which increases the metalens transmittance and improves the light uniformity. In addition, with the new method, the phase differences of all elements in the metalens can also be reduced to be below 0.05°, decreasing the metalens spherical aberration dramatically. This method not only helps us to optimize the metalens but also provides a useful way for designing high-quality metasurfaces. [ABSTRACT FROM AUTHOR]

With the industrial application of syngas, the explosion accident caused by it has gradually become a topic of concern for researchers. In this paper, the effects of CO 2 addition on the deflagration characteristics of syngas-air premixed mixtures were investigated through experiments and numerical simulations. Experiments were carried out inside a T-pipeline, using a high-speed camera and a pressure sensor to simultaneously record the flame evolution and pressure dynamics during deflagration. Simulations were calculated using the GRI 3.0 mechanism by Chemkin Premix Code. The results show that the addition of CO 2 has a certain inhibitory effect on the flame propagation, which can make the finger flame in the vertical pipe evolve into a "tulip" flame. And under the inhibition of CO 2 , the deflagration overpressure of the mixture is reduced, and the number of H, O, OH radicals is also greatly reduced, and the chemical reaction rate is correspondingly slowed down. [Display omitted] • The flame spreads symmetrically in the T-pipeline. • The addition of CO 2 can inhibit the flame propagation in the T-pipeline. • The more CO 2 added, the lower the T-pipeline explosion overpressure. [ABSTRACT FROM AUTHOR]

Aptamer-based strip assay is an easy, highly efficient and low-cost detection method, which has been developed and easily applied to onsite detection. A new sensitive sandwich dipstick assay for adenosine triphosphate (ATP) detection was successfully developed based on specific recognition between split aptamer fragments and the target. In this method, the thiolated aptamer was first conjugated to the surface of gold nanoparticles (AuNPs), while the biotin-aptamer was immobilized on the surface of a nitrocellulose filter in the test line. In the presence of ATP, the thiol-aptamer/ATP/biotin-aptamer complexes were generated, which led to an obvious increase in optical signals at the test line. Under the optimal determination conditions, an excellent linear logarithmic response to the ATP concentration was obtained within the range of 0.5 μM to 5 mM. The limit of detection (LOD) of 0.5 μM was reached at a signal-to-noise ratio of 3. The dipstick assay showed a good average recovery of 96-108 % with the RSD of less than 20 % in urine samples. The proposed method exhibited high specificity against other nucleotides such as the uridine triphosphate (UTP), cytidine triphosphate (CTP), and guanosine triphosphate (GTP). The results indicated that the dipstick strip may be considered as an inexpensive screening tool for onsite ATP determination. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This work reports a composite film using (3-Aminopropyl)triethoxysilane-modified boron nitride nanosheets (BNNS) incorporated in the aramid nanofibers (ANF) network via sol–gel method. High-resolution TEM, SEM, XPS, and XRD outcomes confirmed the imitation pearl layered structure—BNNSs as thermal conductive fillers were layer-by-layer overlapped on ANF. The reasonable coordination between interfaces and fillers stimulated the thermal conductivity (35.4 W/(m·k)) of composite film i.e., 338.43% higher than that of ANF. The composite film exhibited good cyclic thermal stability, high tensile strength (65.9 MPa), and high volume resistivity (2.424×1015 Ω∙cm). [Display omitted] • BNNS@APTES/ANF with imitation pearl layered structure was prepared via sol–gel method. • BNNS as thermal conductive fillers were layer-by-layer overlapped on the ANF. • High thermal conductivity of BNNS@APTES/ANF was 35.4 W/(m·k) higher than pure ANF. • BNNS@APTES/ANF exhibited excellent tensile property and high volume resistivity. • The thermal conductivity of BNNS@APTES/ANF did not decay during 8 cooling/heating cycles. This work reports a composite film using (3-Aminopropyl)triethoxysilane-modified boron nitride nanosheets (BNNS) incorporated in the aramid nanofibers (ANF) network via sol–gel method. High-resolution TEM, SEM, XPS, and XRD outcomes confirmed the imitation pearl layered structure—BNNSs as thermal conductive fillers were layer-by-layer overlapped on ANF. The reasonable coordination between interfaces and fillers stimulated the thermal conductivity (35.4 W (m·k)-1) of composite film i.e., 338.43 % higher than that of ANF. The composite film exhibited good cyclic thermal stability, high tensile strength (65.9 MPa), and high volume resistivity (2.424 × 1015 Ω∙cm). [ABSTRACT FROM AUTHOR]

The enzyme-linked apta-sorbent assay (ELASA) is widely used for the detection of small-molecule compounds as a result of low cost and reagent stability of aptamers. However, enzyme labels used in ELASA still suffer from some drawbacks, such as high production cost and limited stability. To overcome the drawbacks, we reported a nanozyme-linked apta-sorbent assay (NLASA) coupled with surface-enhanced Raman scattering (SERS)-colorimetric dual-mode detection. For nanozyme labels, Pd–Pt bimetallic nanocrystals (Pd–Pt NRs) could catalyze 3,3′,5,5′-tetramethylbenzidine (TMB) to blue TMB2+, whose color variation could not only be distinguished by naked eyes but also had a strong SERS signal. The NLASA method was employed to detect ochratoxin A (OTA) with a limit of detection values of 0.097 nM (0.039 ppb) and 0.042 nM (0.017 ppb) via the colorimetric and SERS methods, respectively. This method was applied for the determination of OTA in wine and grape samples, and the detection results were in a satisfied agreement with those determined by the high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method. The proposed NLASA method provided a rapid and sensitive detection for OTA and could also be broadened for other small-molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • UHPLC-Q-Orbitrap HRMS analysis of both supernatant and naturally-occurring precipitate of Sini decoction. • Totally 99 chemical constituents were identified from the accurate-mass measurements and database searching. • The acid-base complexes were investigated using CSI-MS. Decoctions are a staple of traditional Chinese medicine. This study reports on a comprehensive analysis of the chemical compositions of both the supernatant and naturally-occurring precipitate of Sini decoction using ultra-high-performance liquid chromatography (UHPLC) hyphenated with quadrupole-Orbitrap high-resolution mass spectrometry (Q-Orbitrap HRMS). A total of 99 compounds (40 flavonoids, 34 alkaloids, 7 terpenoids, 3 phenolic acids and 15 other compounds) were tentatively identified in the full-scan MS/data-dependent MS/MS (full-scan MS1/dd-MS2) acquisition mode. Moreover, cold spray ionization-mass spectrometry (CSI-MS) was used to explore the presence of self-assembled complexes between phytochemical ingredients. As a proof-of-concept demonstration, the complexation between one acidic compound (glycyrrhizic acid) and three basic compounds (aconitine, hypaconitine, and mesaconitine) was characterized. This study may present inspiring scientific evidence for the formation of naturally-occurring precipitate, enabling a better understanding of Sini decoction and its therapeutic relevance. [ABSTRACT FROM AUTHOR]

To further investigate the flame dynamics inside the special tubes, experiments were carried out in a T-type tube to investigate the effect of the equivalence ratio and the opening ratio on the deflagration of the methane-air premixed mixture. The changes of flame structure, propagation velocity and overpressure during flame propagation are analyzed. The experimental results shown when equivalence ratio was 1.0 and the outlets was fully open, the mixture burned completely, the flame propagation velocity was the highest, it taken only 51 ms for the flame to spread to the exits at both ends and the flame shape was more symmetrical. Under the same equivalence ratio, the increase of the opening ratio would cause the flame propagation velocity to increase, but the overpressure would decrease. When the opening ratio was 0.25, the resistance encountered during the flame propagation process was the largest, and the turbulence at the fork also increased, the interaction between the two caused the maximum overpressure of 0.58 bar at this time. The coupling effect of overpressure and flame front velocity could also clearly show that the two were positively correlated, and the velocity of the flame propagating to the left and right ends of the horizontal tube was symmetrical. When the equivalence ratio was 1.0, as the opening ratio increases, the time to reach the maximum overpressure peak shown a linear downward trend. These findings add to our knowledge of the deflagration dynamics of special tubes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bioinspired vine-like nanofiber membrane is achieved via facile one-step method. • The membrane possesses special wettability and enhanced flame retardancy. • The oily fumes filtration efficiency is 99.78 %, pressure drop is 68.11 Pa. • The membrane displays good reusability and stability for actual COFs purification. • Achieve a trade-off between purification efficiency and air permeability. Indoor air pollution, especially from cooking oil fumes (COFs), has become a serious issue that affects human health. Obtaining filters that can offer high efficiency, high air permeability and good reusability and stability for COFs removal remains a challenge. Herein, a bioinspired vine-like polyethylene terephthalate/cellulose acetate (PET/CA) composite nanofibrous membrane with high filtration performance, high air permeability and enhanced flame retardancy for COFs removal is achieved via a one-step co-electrospinning process. The nanofibrous membrane consists of hierarchically branched nanofibers to offer small pore size (0.48 μm), high porosity (94.75 %) and low packing density (0.22 g m−3), as well as surface superhydrophobicity (water contact angle of 154°) and superoleophilicity (vegetable oil wetting time of 0.21 s). The nanofibrous filter demonstrates high-efficiency COFs removal (>99.5 %), low air resistance (<70 Pa) and good reusability and stability for actual COFs purification. By virtue of the simple fabrication technique and the superiorities in COFs capture, the bioinspired vine-like hierarchical structured nanofibrous membranes have promising applications for oily fumes filtration and air purification in the catering industry. [ABSTRACT FROM AUTHOR]

Under the condition that the gas composition constant equivalence ratio is Φ = 1, and the initial temperature and initial pressure are T 0 and P 0 , respectively, the experimental study of the premixed gas flames with different hydrogen doping ratios (φ = 10%–40%) is different. The behavior and shape change of propagation in the flaring rate pipe (ƞ = 1.0–0.25). The study found that the pre-mixed gas flame in the flared pipe has undergone more complicated shape changes than other studies. One of the outstanding findings is that the tulip flame appeared twice in this open pipe experiment. And through the high-speed camera and high-frequency pressure sensor to obtain the tulip flame picture and the pressure change in the combustion chamber, comprehensive analysis of the experimental results, and the results show that every appearance of the tulip flame is accompanied by the deceleration of the flame front and the increase of overpressure in the combustion chamber. • An interesting phenomenon in which the tulip flame appears twice in a row was discovered. • Independently designed solenoid valve control switch to ensure that the explosion vent opens or closes on time. • In-depth analysis of the tulip flame from multiple angles. [ABSTRACT FROM AUTHOR]

Non-noble electrocatalysts (such as transition metal sulfides) have been attractive to substitute noble-metal catalysts for oxygen evolution reaction (OER) to advance the practical application of clean energy. Herein, a Fe-doped CoS2 nanoparticles supported CoS2 microspheres@N-doped carbon (Fe-CoS2/CoS2@NC) is prepared as an efficient OER electrocatalyst. The Fe-CoS2/CoS2@NC composite is derived by sulfurizing the metanilic-intercalated Co(OH)2 microspheres decorated with binary active CoFe-Prussian blue analogue (CoFe-PBA) nanoparticles. The obtained composite combines the advantageous characteristics for enhancing electrocatalytic performances: binary active Fe-CoS2 derived from CoFe-PBA, active CoS2, N-doped carbon scaffold to improve electronic conductivity, the appropriate specific surface area and meso/macroporous size distribution to afford rich active sites. The Fe-CoS2/CoS2@NC requires an overpotential of 300 mV to reach a current density of 10 mA cm−2 with a Tafel slope of 72 mV dec−1 in 1.0 M KOH, outperforming those of NC/CoS2, NC/Fe-CoS2 and CoS2. Furthermore, the enhancement is experimentally supported by the low charge-transfer resistance and the large electrochemical active surface area during the OER. The synthesis approach could be extended to provide a tunable hydroxide/PBAs precursor-based approach for designing and preparing hierarchical structures as electrocatalysts. [ABSTRACT FROM AUTHOR]

Nucleic acid aptamers are oligonucleotide sequences screened by an in vitro methodology called Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Known as "chemical antibodies", aptamers can achieve specific recognition towards the targets through conformational changes with high affinity, and possess multiple attractive features including, but not limited to, easy and inexpensive to prepare by chemical synthesis, relatively stable and low batch-to-batch variability, easy modification and signal amplification, and low immunogenicity. Now, aptamers are attracting researchers' attentions from more than 25 disciplines, and have showed great potential for application and economic benefits in disease diagnosis, environmental detection, food security, drug delivery and discovery. Although some aptamers exist naturally as the ligand-binding elements of riboswitches, SELEX is a recognized method for aptamers screening. After thirty-two years of development, a series of SELEX methods have been investigated and developed, as well as have shown unique advantages to improve sequence performances or to explore screening mechanisms. This review would mainly focus on the novel or improved SELEX methods that are available in the past five years. Firstly, we present a clear overview of the aptamer's history, features, and SELEX development. Then, we highlight the specific examples to emphasize the recent progress of SELEX methods in terms of carrier materials, technical improvements, real sample-improved screening, post-SELEX and other methods, as well as their respects of screening strategies, implementation features, screening parameters. Finally, we discuss the remaining challenges that have the potential to hinder the success of SELEX and aptamers in practical applications, and provide the suggestions and future directions for developing more convenient, efficient, and stable SELEX methods in the future. [Display omitted] • The review mainly focused on the novel or improved SELEX methods that are available in the past five years. • Five major categories of SELEX were emphasized on their respects of screening strategies, implementation features, as well as screening parameters. • The challenges and future directions were concluded and depicted for more efficient and practical SELEX. [ABSTRACT FROM AUTHOR]

This test represents a water quality improvement exemplary project in relation to a tributary section of the Maozhou River located within the Bao'an District, Shenzhen, China. It uses in situ pollution control, aeration, and biofilm combined technologies to treat black and odorous water in situ. Three kinds of aeration equipment are used in the test project: a micronano aerator, push-flow aerator, and jet aerator. The operation results show that the micronano aerator is better than the push-flow aerator, and the push-flow aerator is better than the jet aerator. Three biological fillers were used in the test project: carbon fiber grass, AquaMats ecobase, and biological ribbon. The operation results show that the carbon fiber grass is better than the AquaMats ecobase, and the AquaMats ecobase is better than the biological ribbon. After processing, it was found out that the later transparency, dissolved oxygen (DO), oxidation-reduction potential (ORP), Ammonia nitrogen content index (NH3-N), dichromate oxidizability (CODcr), and biochemical oxygen demand (BOD5) all could comply with the requirements of treatment, indicating that the combined technology is practically viable. The combination technology can provide valuable reference for the treatment of urban black and odorous water. [ABSTRACT FROM AUTHOR]