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Odors existing in natural environment are typically mixtures of a large variety of chemical compounds in specific proportions. It is a challenging task for an electronic nose to recognize the gas mixtures. Most current research is based on the overall response of sensors and uses relatively simple datasets, which cannot be used for complex mixtures or rapid monitoring scenarios. In this study, a novel electronic nose (E-nose) using a spiking neural network (SNN) model was proposed for the detection and recognition of gas mixtures. The electronic nose integrates six commercial metal oxide sensors for automated gas acquisition. SNN with a simple three-layer structure was introduced to extract transient dynamic information and estimate concentration rapidly. Then, a dataset of mixed gases with different orders of magnitude was established by the E-nose to verify the model's performance. Additionally, random forests and the decision tree regression model were used for comparison with the SNN-based model. Results show that the model utilizes the dynamic characteristics of the sensors, achieving smaller mean squared error (MSE < 0.01) and mean absolute error (MAE) with less data compared to random forest and decision tree algorithms. In conclusion, the electronic nose system combined with the bionic model shows a high performance in identifying gas mixtures, which has a great potential to be used for indoor air quality monitoring in practical applications. [ABSTRACT FROM AUTHOR]

Biomedical sensing technology is developing at a tremendous pace and is expected to become an effective clinical tool for the diagnosis and monitoring of human health. The development of sensing devices has successfully transformed the specific sensor prototype designed in the laboratory into a commercially feasible clinical disease detection device. Recently, sensing devices have been accelerated and extended to various fields beyond disease detection, including the measurement of gastrointestinal physiological parameters such as pH, VOC detection, small-molecule gas sensing, and noninvasive screening of oral and lung diseases such as oral cancer, gastric cancer, and other major diseases. In this review, the applications of sensors and electronic nose devices in the diagnosis and monitoring of oral, pulmonary, and gastrointestinal diseases are reviewed, as well as the design and application of sensor materials in disease markers and in situ detection. This article also introduces the practical application of sensing devices in human disease detection, critically analyzes their detection mechanisms and clinical utility, and discusses their future development in medicine. We believe that this review will help readers, especially practitioners in the medical field, provide ideas for the development of sensing devices. [ABSTRACT FROM AUTHOR]

Calcium ions participate in the regulation of almost all biological functions of the body, especially in cardiac excitation–contraction coupling, acting as vital signaling through ion channels. Various cardiovascular drugs exert their effects via affecting the ion channels on the cell membrane. The current strategies for calcium ion monitoring are mainly based on fluorescent probes, which are commonly used for intracellular calcium ion detection (calcium imaging) and cannot achieve long-term monitoring. In this work, an all-solid-state silicone–rubber ion-sensitive membrane was fabricated on light-addressable potentiometric sensors to establish a program-controlled field-effect-based ion-sensitive light-addressable potentiometric sensor (LAPS) platform for extracellular calcium ion detection. L-type calcium channels blocker verapamil and calcium channel agonist BayK8644 were chosen to explore the effect of ion channel drugs on extracellular calcium ion concentration in HL-1 cell lines. Simultaneously, microelectrode array (MEA) chips were employed to probe the HL-1 extracellular field potential (EFP) signals. The Ca2+ concentration and EFP parameters were studied to comprehensively evaluate the efficacy of cardiovascular drugs. This platform provides more dimensional information on cardiovascular drug efficacy that can be utilized for accurate drug screening. [ABSTRACT FROM AUTHOR]

Coronary rotational atherectomy is an effective technique for treating cardiovascular disease by removing calcified tissue using small rotary grinding tools. However, it is difficult to analyze the stress force on vessel walls using experiments directly. Using computational fluid dynamics is a better way to study the stress force characteristics of the burr grinding procedure from a fluid dynamics perspective. For this purpose, physical and simulation models of atherosclerotic plaque removal were constructed in this study. The simulation results show that smaller ratios between the burr and arterial diameter (B/A = 0.5) result in a more stable flow field domain. Additionally, the pressure and stress force generated by the 4.5 mm diameter grinding tool reach 92.77 kPa and 10.36 kPa, surpassing those of the 2.5 mm and 3.5 mm grinding tools. The study has demonstrated the use of computational fluid dynamics to investigate wall shear stress characteristics in medical procedures, providing valuable guidance for optimizing the procedure and minimizing complications. [ABSTRACT FROM AUTHOR]

The IEEE 802.11 standard provides multi-rate support for different versions. As there is no specification on the dynamic strategy to adjust the rate, different rate adaptation algorithms are applied according to different manufacturers. Therefore, it is often hard to interpret the performance discrepancy of various devices. Moreover, the ever-changing channels always challenge the rate adaptation, especially in the scenario with scarce spectrum and low SNR. As a result, it is important to sense the radio environment cognitively and reduce the unnecessary oscillation of the transmission rate. In this paper, we propose an environment-aware robust (EAR) algorithm. This algorithm employs an occasional small packet, designs a rate scheme adaptive to the environment, and enhances the robustness. We verify the throughput of EAR using network simulator NS-3 in terms of station number, motion speed and node distance. We also compare the proposed algorithm with three benchmark methods: AARF, RBAR and CHARM. Simulation results demonstrate that EAR outperforms other algorithms in several wireless environments, greatly improving the system robustness and throughput. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationships between sleep duration and depression among middle-aged and older adults in China. Methods: This study used the data of 17,744 respondents from the 2018 China Health and Retirement Longitudinal Study (CHARLS), an ongoing national longitudinal survey of Chinese adults aged 45 years and above. Self-reported sleep duration per night was obtained from face-to-face interviews. Depression was evaluated using the 10-item Center for Epidemiological Studies-Depression scale (CES-D 10). The multivariable generalized linear model (GLM) was adopted to estimate the associations between sleep duration and depression. Results: Of the 17,744 respondents, 8425 (47.5%) were men. The mean (SD) age was 62.6 (10.0) years old. Respondents with short (≤4, 5 h per night) sleep duration had a higher risk of depression [odds ratio (OR): 2.77, 95% confidence interval (CI): 2.35–3.27), p < 0.001; OR: 1.65, 95% CI: 1.38–1.98, p < 0.001] compared with those slept for 7 h per night after adjusting for covariates. Long sleep duration (8, 9, ≥10) had no significant risk for depression. Restricted cubic splines analysis suggested that when sleep duration fell below 9 h, increased sleep duration was associated with a significantly lower risk of depression (OR: 0.82, 95% CI: 0.79–0.84, p < 0.001). When sleep duration exceeded 9 h, the risk of depression (OR: 1.03, 95% CI: 0.94–1.14, p = 0.512) would not increase significantly facing prolonged sleep duration. Conclusions: Short sleep duration was associated with depressive symptoms among middle-aged and older adults in China. Future studies are needed to focus on examining the cause-effect relationship between sleep duration and depression. [ABSTRACT FROM AUTHOR]

Objective: At the global level, a multi-country outbreak of monkeypox has attracted global attention. The purpose of this study is to explore the growing contribution of global research on monkeypox. Methods: Publications related to monkeypox were retrieved from PubMed and Web of Science. Bibliometric analyses were conducted by VOSviewer and CiteSpace software to generate network maps, evaluate hot topics in the field, and identify cooperation patterns between different authors and countries. Results: A total of 1822 publications were retrieved to reflect the global overall monkeypox research output, including clinical trials, systematic reviews, case reports, and laboratory studies. The most productive country and institution were respectively the United States and Centers for Disease Control and Prevention—USA (CDC). The top three authors with the highest number of publications were all from the CDC. Research hotspots included some monkeypox-related diseases, such as smallpox and vaccinia, and the prevention and treatment of monkeypox diseases, such as antiviral drugs and smallpox vaccines. Research fronts included real-time PCR, immune evasion, animal models, and monkeypox outbreak countries (Democratic Republic of Congo and others). Conclusions: Research on monkeypox is mainly carried out from the aspects of its source, transmission route, virus prevalence, and prevention and control measures. Controlling monkeypox is a global responsibility, and the future research into monkeypox control methods is suggested to focus on more than vaccines. [ABSTRACT FROM AUTHOR]

Knowing the molecular mechanism of male sterility in alfalfa is important to utilize the heterosis more effectively. However, the molecular mechanisms of male sterility in alfalfa are still unclear. In this study, the bulked segregant analysis (BSA) and bulked segregant RNA-seq (BSR) were performed with F2 separation progeny to study the molecular mechanism of male sterility in alfalfa. The BSA-seq analysis was located in a candidate region on chromosome 5 containing 626 candidate genes which were associated with male sterility in alfalfa, while the BSR-seq analysis filtered seven candidate DEGs related to male sterility, and these candidate genes including EF-Tu, β-GAL, CESA, PHGDH, and JMT. The conjunctive analyses of BSR and BSA methods revealed that the genes of Msβ-GAL and MsJMT are the common detected candidate genes involved in male sterility in alfalfa. Our research provides a theory basis for further study of the molecular mechanism of male sterility in alfalfa and significant information for the genetic breeding of Medicago sativa. [ABSTRACT FROM AUTHOR]

The practice of odorant analysis can often be very challenging because odorants are usually composed of a host of volatile organic compounds (VOCs) at low concentrations. Preconcentration with solid phase microextraction (SPME) is a conventional technique for the enrichment of these volatile compounds before analysis by headspace gas chromatography-mass spectrometry (GC-MS). However, commercially available SPME products usually bear the defects of weak mechanical strength and high cost. In this work, novel SPME fibers were prepared by a one-pot synthesis procedure from divinylbenzene (DVB), porous carbon powder (Carbon) and polydimethylsiloxane (PDMS). Factors that influence the extraction efficiency, such as extraction temperature, extraction time, salting effects, pH, stirring rate, desorption temperature and time, were optimized. VOCs in landfills pose a great threat to human health and the environment. The new SPME fibers were successfully applied in the analysis of VOCs from the leachate of a cyanobacteria landfill. Quantification methods of major odor contributors were established, and a good linearity (r > 0.998) was obtained, with detection limits in the range of 0.30–0.50 ng/L. Compared to commercial SPME fibers, the new material has higher extraction efficacy and higher precision. Hence, it is suitable for the determination of hazardous odorants of various sources. [ABSTRACT FROM AUTHOR]

With the continuous process of urbanization, regional integration has become an inevitable trend of future social development. Accurate prediction of passenger volume is an essential prerequisite for understanding the extent of regional integration, which is one of the most fundamental elements for the enhancement of intercity transportation systems. This study proposes a two-phase approach in an effort to predict highway passenger volume. The datasets subsume highway passenger volume and impact factors of urban attributes. In Phase I, correlation analysis is conducted to remove highly correlated impact factors, and a random forest algorithm is employed to extract significant impact factors based on the degree of impact on highway passenger volume. In Phase II, a deep feedforward neural network is developed to predict highway passenger volume, which proved to be more accurate than both the support vector machine and multiple regression methods. The findings can provide useful information for guiding highway planning and optimizing the allocation of transportation resources. [ABSTRACT FROM AUTHOR]

As a countermeasure to urban exhaust pollution and traffic congestion, traffic restriction policy (TRP) and carpooling strategy have been widely introduced throughout the world. However, their effects are largely determined by the rationality of implementing policies, and unreasonable policies make them controversial on the long-term implementation benefits. To more effectively manage traffic demand and maintain the sustainability of transportation system, it is necessary to make optimization for management policy before implementation. In this paper, the elastic demand model and equilibrium assignment model are developed under TRP. Considering the negative impact of the mandatory TRP on the public acceptance, we propose a novel TRP strategy, namely TRP with carpool exemptions (TRP-CE), that is, a proportion of high occupancy vehicles (HOV) are allowed to travel in the restricted district even if their license plate numbers are restricted. Then, a bi-level programming model is proposed to solve the optimal schemes by combining multi purposes of ensuring travel convenience, alleviating traffic congestion, and reducing the exhaust pollution. Finally, a numerical experiment is conducted to evaluate the effectiveness of proposed models and make comparative analysis between separate TRP and TRP-CE. The results indicate that TRP-CE has benefits in the following aspects: (1) Carpool exemptions provide an incentive to carpool for travelers by private cars; (2) the public acceptance of TRP is improved by introducing carpool exemptions as a compensatory mitigation strategy for mandatory TRP; (3) the implementation effect of demand management can be well achieved by joint optimization; and (4) there is no need to design and reconstruct HOV lanes for the implementation of TRP-CE, which is convenient for practical application. [ABSTRACT FROM AUTHOR]

As a countermeasure to urban exhaust pollution and traffic congestion, traffic restriction based on the last digit of license plate numbers has been widely introduced throughout the world. However, the effect of traffic restriction is weakened as it causes the long-distance detour of restricted travel modes and induces travel demand to shift to unrestricted travel modes. To consider detour and shift of traffic demand caused by traffic restriction, we propose a stochastic user equilibrium model under traffic rationing based on mode shifting rate and the corresponding solution algorithm. A case study is conducted to verify the effectiveness of proposed model and algorithm. Main findings of numerical experiments include: (1) Compared with traditional stochastic user equilibrium model, the temporary traffic demand shift caused by long-distance detour are well considered in proposed model. (2) Sensitivity analysis of the consumption parameters used in the proposed model shows that, the involved cost parameters have different effectiveness on the mode shifting rate. This study provides a reasonable relaxation of the intensively used assumption, that all restricted vehicles outside the restricted district will detour in traffic rationing research, and provides a reasonable approach to evaluate the change of link flow and the beneficial effectiveness on the sustainability of traffic environment after implementation of traffic restriction policy. [ABSTRACT FROM AUTHOR]

Intercity transport systems have been plagued by low efficiency and overutilization for a long time, due to unhealthy competition among multi-transport modes. Hence, this study aims to estimate the dominant trip distance of intercity passenger transport modes to optimize the allocation of intercity passenger transport resources and improve the efficiency of intercity transport systems. Dominant trip distance was classified into two types: Absolute dominant trip distance and relative dominant trip distance; and their respective models were developed using passenger transport mode share functions and fitting curves. Particularly, the big data of intercity passenger transport mode share rate of more than 360 cities in China was obtained using a network crawler and each passenger transport mode share function and their curves were proposed. Furthermore, the dominant trip distances estimation models of intercity passenger transport were developed and solved. The results show that there are significant differences in dominant trip distance between the transport modes. For example, the absolute and relative dominant trip distances of highway are 8–119 km and 8–463 km, respectively, while those of airway are 1594–3000 km and 2477–3000 km, respectively. [ABSTRACT FROM AUTHOR]

AlCoCrFeNiTi high-entropy alloy coatings (HEACs) were prepared by mechanical alloying (MA) and laser cladding (LC) process on H13 hot-working die steel substrate. Phase evolution, microstructure, and mechanical properties of the alloyed powder and HEACs were investigated in detail. The final milling AlCoCrFeNiTi coating powders exhibited simple body centered cubic (BCC) phase and mean granular size of less than 4 μm. With the increase of heat input of the laser, partial BCC phase transformed into minor face centered cubic (FCC) phase during LC. AlCoCrFeNiTi HEACs showed excellent metallurgical bonding with the substrate, and few defects. Moreover, the microhardness of AlCoCrFeNiTi HEACs reached 1069 HV due to the existence of the hard oxidation and the second phase grains, which are about five times that of the substrate. The laser surface cladding HEACs exhibited deteriorated tensile property compared with that of the substrate and the fracture generally occurred in the region of HEACs. The fracture mechanism of AlCoCrFeNiTi HEACs was dominated by the comprehensive influence of brittle fracture and ductile fracture. [ABSTRACT FROM AUTHOR]

Traffic control is very important for two-lane highway lane-closure work zone traffic management. Control of the open lane's right of way is very similar to that of a two-phase signalized intersection. Thus, four control strategies including flagger control, pre-timed control proposed by Schonfeld, pre-timed control proposed by Webster, and actuated control are employed for possible use at work zones. Two primary methodologies, the mathematical delay model adopted from signalized intersections, and the simulation model calibrated with field data, are proposed. The simulation and mathematical results show that control strategies for two one-way road intersections could be used for two-lane highway lane-closure work zones. Flagger control after gap-out distance optimization prevails over all the other control strategies in terms of stopped delay, queue length, and throughput, under low or high volumes. Actuated control could be a good alternative for work zone areas due to its small queue length and large vehicle throughput under moderate volume conditions. Our findings may help to optimize the work-zone control strategy and improve operational efficiency at two-lane highway lane-closure work zones. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Sustainability of Abandoned Slopes in the Hill and Gully Loess Plateau Region Considering Deep Soil Water" that appeared in the previous issue.

Soil desiccation of the deep soil layer is considered one of the main limiting factors to achieving sustainable development of ecosystems in the hill and gully Loess Plateau region. In this study, slope croplands were selected as the control, and deep soil water was studied on abandoned slopes, including natural abandoned slopes, Robinia pseudoacacia plantations, and Caragana korshinskii plantations. Then, we explored deep soil water characteristics of different vegetation types and slope aspects and the variation tendencies of deep soil water at different recovery stages. The results showed that there were no significant differences in deep soil water content between sunny and shady slopes, and thus, slope aspect was not the key impact factor affecting deep soil water. Deep soil water content on R. pseudoacacia plantations and C. korshinskii plantations was lower than that on natural abandoned slopes; there were no significant differences in soil water content between the natural abandoned slopes and slope croplands. Soil desiccation did not exist on natural abandoned slopes; thus, natural vegetation restoration is an appropriate way to achieve a sustainable ecosystem with respect to deep soil water. In contrast, soil desiccation intensified until it was difficult for vegetation to obtain available water in the deep soil layer on the plantations; soil desiccation began to appear at the 11–20-year stage, and it became increasingly severe until the deep soil water was close to the wilting coefficient at the ≥30-year stage on R. pseudoacacia plantations. Deep soil water was rapidly consumed, and soil desiccation began to appear at the 1–10-year stage and then was close to the wilting coefficient in the later stages on C. korshinskii plantations. According to the results, the plantations needed to be managed in a timely manner to prevent or reduce soil desiccation. [ABSTRACT FROM AUTHOR]