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Theophylline is a kind of methyl xanthine derivative that can be found in various foods and is a widely used bronchodilator drug. It is significant to detect theophylline by a sensitive, low-cost, and rapid determination technique. In the investigation, zinc oxide (ZnO) nanoparticles and multiwalled carbon nanotubes (MWCNTs) co-modified carbon paste electrode (CPE) was fabricated by a simple procedure and then was successfully applied to determine theophylline. The electrochemical behavior of the modified electrode was explored using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Compared with the bare CPE and MWCNTs/CPE, the ZnO-modified MWCNTs/CPE electrode (ZnO/MWCNTs/CPE) exhibited good promoting effect on the electrochemical reaction of theophylline. Under the optimized experimental statuses, the differential pulse voltammetric peak currents can be used to detect TP, since it had a linear relationship with the theophylline concentration in the range of 3.3 × 10−7–1.3 × 10−4M. The detection limit is 8.3 × 10−8M (S/N= 3), and the sensitivity is 0.12048 μA μM−1. Furthermore, the fabricated sensor shows high sensitivity, good selectivity, and good stability toward theophylline determination. Finally, we used the prepared electrode as an actual sample to the determination of theophylline in pharmaceutical formulations.

Joint control has been proposed to alleviate the negative spillover of the pandemic. The authority faces a decision dilemma on whether to undertake joint control, which is overlooked by the scientific community. This paper, aiming to clarify the decision-making mechanism under cost optimization, draws on the optimization theory to find the optimal strategies and start time under independent and joint scenarios with an improved infectious disease model. Besides, a simulation analysis, based on the survey in Ruili – a border area between Myanmar and China, is employed. The crucial findings highlight that (1) The control measures contribute to reducing the peak number or peak time of confirmed patients under optimal decision. (2) As the delay of start time, the epidemic control for both countries undergoes from validity to failure. (3) More cost-savings come with earlier joint control but with uneven distribution. Joint strategy mitigates the cost for the one with severe epidemics, but the effect is insignificant for the other. This study, concentrating on cost optimization, provides a novel insight into pandemic control. The results enrich the decision analysis in the context of pandemic joint governance while providing inter-regional control support for the decision-maker to tackle various epidemics.

The hippocampus provides significant inspiration for spatial navigation and memory in both humans and animals. Constructing large-scale spiking neural network (SNN) models based on the biological neural systems is an important approach to comprehend the computational principles and cognitive function of the hippocampus. Such models are usually implemented on neuromorphic computing platforms, which often have limited computing resources that constrain the achievable scale of the network. This work introduces a series of digital design methods to realize a Field-Programmable Gate Array (FPGA) friendly SNN model. The methods include FPGA-friendly nonlinear calculation modules and a fixed-point design algorithm. A brain-inspired large-scale SNN of ∼21 k place cells for path planning is mapped on FPGA. The results show that the path planning tasks in different environments are finished in real-time and the firing activities of place cells are successfully reproduced. With these methods, the achievable network size on one FPGA chip is increased by 1595 times with higher resource usage efficiency and faster computation speed compared to the state-of-the-art.

ObjectiveThe goal was to analyse website content of Chinese electronic (e) cigarette manufacturing enterprises and understand the marketing strategies to provide evidence for decision-makers to regulate manufacturers.MethodsThrough QCC.com, one of the largest enterprise information query platforms in China, we identified 104 official manufacturer websites in 2021. A codebook including 6 sections with 31 items was developed and all webpages were coded separately by two trained researchers.ResultsOver half of the websites (56.7%) did not have age verification for entry. Thirty-two (30.8%) websites had no restriction for minors to use or purchase e-cigarettes, and 79 (76.0%) had no health warning. Overall, 99 websites (95.2%) displayed their products, and 72 (69.2%) displayed e-flavours. The most frequently used descriptions of products included good taste (68.3%), positive mood (62.5%), leakage resistance (56.7%), enjoyment (47.1%), reduced harm (45.2%), alternatives to cigarettes (43.3%) and long battery life (42.3%). Additionally, 75 websites (72.1%) provided contact information on different channels, including WeChat (59.6%), Weibo (41.3%), Facebook (13.5%), Instagram (12.5%) and brand apps (2.9%). Manufacturers provided investment and franchise information (59.6%) and offline store information (17.3%). In addition, 41.3% websites included content regarding corporate social responsibility.ConclusionsChinese e-cigarette manufacturers’ official websites have become a platform for presenting product and brand information, establishing online and offline marketing loops, and displaying corporate social responsibility with weak age restrictions on access and a lack of health warnings. The Chinese government should implement strict regulatory measures on e-cigarette enterprises.

ObjectivesTo assess the relative benefits of various non-pharmacological interventions on treating primary dysmenorrhoea within a network meta-analysis.Study designSystematic review and Bayesian network meta-analysis.Inclusion criteriaRandomised controlled trial involving patient with primary dysmenorrhoea and received non-pharmacological interventions.Data sourcesFour databases (Medline, Embase, Cochrane Library and Web of Science) were searched from inception to October first, 2022.Risk-of-bias (RoB) assessmentRoB 2.0 assessment tools was used to assess the risk of bias in the included studies.Synthesis of resultsConventional meta-analysis was conducted by pairwise comparison between non-pharmacological therapy and control treatment. The Bayesian network meta-analysis was conducted by the Aggregate Data Drug Information System Software based on the consistency or inconsistency model, and rank probability was used to indicate the priority of non-pharmacological therapy.Results33 studies involving eight non-pharmacological interventions were included. With regard to conventional meta-analysis, we selected Visual Analogue Scale (VAS) as primary outcome to evaluate the pain intensity. The result showed that eight interventions (Exercise, Herb, Acupuncture, Aromatherapy, Transcutaneous Electrical Nerve Stimulation, Topical heat, Acupressure, Yoga) displayed positive effect on reduction of menstrual pain compared with placebo or no treatment. A Bayesian network meta-analysis revealed that exercise −3.20 (95% CI −4.01 to −2.34), acupuncture −2.90 (95% CI −3.97 to −2.85) and topical heat −2.97 (95% CI −4.66 to −1.29) probably resulted in a reduction in pain intensity (VAS) .ConclusionsNon-pharmacological interventions may result in a reduction or slight reduction in pain intensity compared with no treatment or placebo. Specifically, exercise and acupuncture are considered as potentially effective non-pharmacological treatments in short-term treatment. Indeed, larger and better methodological quality research is needed.Trial registration numberCRD42022351021.

The information in Spiking Neural Networks (SNNs) is carried by discrete spikes. Therefore, the conversion between the spiking signals and real-value signals has an important impact on the encoding efficiency and performance of SNNs, which is usually completed by spike encoding algorithms. In order to select suitable spike encoding algorithms for different SNNs, this work evaluates four commonly used spike encoding algorithms. The evaluation is based on the FPGA implementation results of the algorithms, including calculation speed, resource consumption, accuracy, and anti-noiseability, so as to better adapt to the neuromorphic implementation of SNN. Two real-world applicaitons are also used to verify the evaluation results. By analyzing and comparing the evaluation results, this work summarizes the characteristics and application range of different algorithms. In general, the sliding window algorithm has relatively low accuracy and is suitable for observing signal trends. Pulsewidth modulated-Based algorithm and step-forward algorithm are suitable for accurate reconstruction of various signals except for square wave signals, while Ben's Spiker algorithm can remedy this. Finally, a scoring method that can be used for spiking coding algorithm selection is proposed, which can help to improve the encoding efficiency of neuromorphic SNNs.

The further exploration of the neural mechanisms underlying the biological activities of the human brain depends on the development of large-scale spiking neural networks (SNNs) with different categories at different levels, as well as the corresponding computing platforms. Neuromorphic engineering provides approaches to high-performance biologically plausible computational paradigms inspired by neural systems. In this article, we present a biological-inspired cognitive supercomputing system (BiCoSS) that integrates multiple granules (GRs) of SNNs to realize a hybrid compatible neuromorphic platform. A scalable hierarchical heterogeneous multicore architecture is presented, and a synergistic routing scheme for hybrid neural information is proposed. The BiCoSS system can accommodate different levels of GRs and biological plausibility of SNN models in an efficient and scalable manner. Over four million neurons can be realized on BiCoSS with a power efficiency of 2.8k larger than the GPU platform, and the average latency of BiCoSS is 3.62 and 2.49 times higher than conventional architectures of digital neuromorphic systems. For the verification, BiCoSS is used to replicate various biological cognitive activities, including motor learning, action selection, context-dependent learning, and movement disorders. Comprehensively considering the programmability, biological plausibility, learning capability, computational power, and scalability, BiCoSS is shown to outperform the alternative state-of-the-art works for large-scale SNN, while its real-time computational capability enables a wide range of potential applications. [ABSTRACT FROM AUTHOR]

Upstream vortex has a significant effect on the secondary flow structure of the downstream turbine in the stage environment. This study investigates the secondary flow structure with non-axisymmetric endwall profiling (NAEW) under the interaction of co-rotating incoming vortex (Vic). A half-delta wing vortex generator is utilized to model Vic. The turbine cascade case which exhibited maximum reduction of the cascade loss with NAEW under no incoming vortex is studied. The mechanism of loss reduction with NAEW under the interaction of Vicis analysed. Viccould decrease the secondary flow near the endwall region by affecting the horseshoe vortex transport in the cascade. However, its loss reduction was lower than the loss increments of Vicitself. The arrival of Vicat the leading edge of the cascade increased the strength of the horseshoe vortex, resulting in a significant increase in loss. Under the interaction of Vic, NAEW decreased the blade loading near endwall region, which resulted in the reduction of cascade loss.

The dysfunction of innate immunity components is one of the major drivers for ulcerative colitis (UC), and increasing reports indicate that gut microbiome serves as an intermediate between genetic mutations and UC development. Here, we find that the IL-17 receptor subunit, CMTM4, is reduced in UC patients and dextran sulfate sodium (DSS)-induced colitis. The deletion of CMTM4 (Cmtm4−/−) in mice leads to a higher susceptibility to DSS-induced colitis than in wildt-ype, and the gut microbiome significantly changes in the composition. The causal role of gut microbiome is confirmed with cohousing experiment. We further identify that S100a8/9 is significantly up-regulated in Cmtm4−/−colitis, with the block of its receptor RAGE that reverses the phenotype associated with the CMTM4 deficiency. CMTM4 deficiency rather suppresses S100a8/9 expression in vitro via the IL17 pathway, further supporting that the elevation of S100a8/9 in vivois most likely a result of microbial dysbiosis. Taken together, the results suggest that CMTM4 is involved in the maintenance of the intestinal homeostasis, suppression of S100a8/9, and prevention of the colitis development. Our study further shows CMTM4 as a crucial innate immunity component, confirming its important role in the UC development and providing insights into potential targets for development of future therapies.

Biomass carbon for sodium ion anode material has advantages of wide source, low cost, and renewable resources, but poor electrochemical performance limits its commercial application. In this work, we propose a hybrid composite based on few-layer MoS22D nano-structures and tubular sisal fiber carbon (TSFC) micro-structures as anode materials for SIBs, where the in situ vertical growth of MoS2nanosheets uniformly on TSFC was successfully obtained by a simple hydrothermal method. It is found that the synthesis conditions play an important role in the formation of MoS2nanosheets and provide tunable structure, morphology, and electrochemical property for the proposed composites. The unique cross-linked network micro-nano-structures of the MoS2/TSFC can effectively improve the electrochemical performance of the anode materials, which shows a reversible specific capacity up to 243 mAh g−1after 500 long-term cycles at a current density of 0.1 A g−1, with a capacity retention of 97 % from 200 to 500 cycles, and a high initial coulombic efficiency of 64 %. This work can provide a new way of resource utilization for natural sisal cellulose, and obtain a new low-cost high-performance sodium ion battery anode material.

A systematic study of the synthesis of C.I. Acid Blue 9 leuco compound in water is reported. The kinetic analysis of experimental data for the condensation reaction between 2-formylbenzenesulfonic acid sodium and N-ethyl-N-(3′-sulfonic acid benzyl) aniline obtained at four different temperatures ranging between 85 and 100°C is discussed. It is shown that the reaction followed second-order rate kinetics. The overall rate constant (k) increased with the increase of temperature. On the basis of the value of k, activation energy (Ea) of the reaction was evaluated. Importantly, it is found that reactant concentration has great effect on the formation of C.I. Acid Blue 9 leuco compound, implying that it is not enough to improve the conversion of N-ethyl-N-(3′-sulfonic acid benzyl) aniline by only prolonging reaction time in the late period of the reaction.

The development of a highly selective, simple, and rapid detection method for nitrofuran antibiotics (NFs) is of great significance for food safety, environmental protection, and human health. To meet these needs, in this work, cyan-color highly fluorescent N-doped graphene quantum dots (N-GQDs) were synthesized using cane molasses as the carbon source and ethylenediamine as the nitrogen source. The synthesized N-GQDs have an average particle size of 6 nm, a high fluorescence intensity with 9 times that of undoped GQDs, and a high quantum yield (24.4%) which is more than 6 times that of GQDs (3.9%). A fluorescence sensor based on N-GQDs for the detection of NFs was established. The sensor shows advantages of fast detection, high selectivity, and sensitivity. The limit of detection for furazolidone (FRZ) was 0.29 μM, the limit of quantification (LOQ) was 0.97 μM, and the detection range was 5–130 μM. The fluorescence quenching mechanism of the sensor was explored by fluorescence spectroscopy, UV–vis absorption spectroscopy, Stern–Volmer quenching constant, Zeta potential, UV–vis diffuse reflectance spectroscopy, and cyclic voltammetry. A fluorescence quenching mechanism of dynamic quenching synergized with photoinduced electron transfer was revealed. The developed sensor was also successfully applied for detecting FRZ in various real samples, and the results were satisfactory.

Three types of ligands have been developed for copper-catalyzed Ullmann cross coupling reaction of bromaminic acid with amines in aqueous solution. Ligands with large steric hindrance and strong electron-donating capacity were beneficial to the reaction. UV–Vis and CV analyses demonstrated that these ligands had strong coordination with copper(I), implying the effect of ligand coordination ability on the stability and catalytic activity of catalytic system.

Cellulose-derived materials have attracted extensive attention for applications in advanced electronics due to their abundance, low cost, light weight, and sustainability. Here, we report a paper-based triboelectric nanogenerator (TENG) which was made of sisal cellulose as the friction layer. The effects of the surface morphology, structure, and dielectric properties of sisal cellulose paper (SCP) on the output performance of SCP-TENG were discussed. It is found that the electrical output performance of the SCP-TENG can be improved and controlled by chemically modifying SCP with different polar groups of -NO2, -COCH3, -Cl, -Br, -CH3, -C2H5, which is closely related to the dielectric constant change of SCP. Among them, the dielectric constant of the nitrated SCP is the highest, and the electrical output performance of the corresponding SCP-TENG also exhibits the highest, with the short-circuit current, open-circuit voltage, charge and power density improving to 20.78 μA, 198 V, 103 nC/m2, 827.03 mW/m2, from 6.13 μA, 118 V, 53 nC/m2, and 256.97 mW/m2, respectively. Based on the linear relationship between the current intensity of the modified SCP-TENG and the degree of substitution of different groups, a chemical sensor for detecting the degree of group substitution was successfully fabricated. This work provides a new idea for broadening the application field of TENG.

A simple rectangular-structured freestanding liquid–solid triboelectric nanogenerator (LS-TENG) was fabricated, which used fluorinated ethylene propylene (FEP) films and deionized water (DI) as friction materials. The LS-TENG can effectively convert mechanical energy into electrical energy under the extremely low-frequency shaking of 2 Hz and shows greatly reliable stability. The influence of liquid volume and units on the output performance of the LS-TENG was studied, and the mechanism of the triboelectric electrification process of the LS-TENG was analyzed by COMSOL Multiphysics software. The results show that friction materials, liquid types, and number of units have a great effect on the output performance of the LS-TENG. Under the optimized conditions, the designed array LS-TENG shows high output performance with the open-circuit voltage, short-circuit current, and transferred charge of 120 V, 3.9 μA, and 133 nC, respectively. The LS-TENG can be applied in capacitive storage, AC power, signal acquisition, and self-powered sensor. The multifunctional LS-TENG provides a potentially practical route for harvesting low-frequency mechanical energy in natural environments and enabling multifunctional applications.

Triphenylborane asymmetrically transfers its phenyl group to N-diphenylphosphinoylarylimines to give diarylmethylamines with high ee in high yield without imine hydrolysis under the catalysis of a chiral amidomonophosphane–rhodium(i) complex.

The bulkiness of the N‐phosphorus groups at imines (I) influences both the reactivity and enantioselectivity of the rhodium/chiral amidophosphane catalyzed arylation reaction with boroxine (II).

The proline‐derived catalyst (I) is effective in the title reaction.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

For Abstract see ChemInform Abstract in Full Text.