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Abstract In the context of automated driving, the connected and automated vehicles (CAVs) technology unlock the energy saving potential. This paper develops an LSTM‐based deep learning framework for eco‐driving adaptive identification on Intelligent vehicle multivariate time series data. The framework can be adapted for Driver Assistance Systems (DAS) to reduce fuel consumption. Specifically, considering overtaking on rural road is a critical maneuver for operation and has potential to reduce consumption, a simulated driving experiment with 30 participants was conducted to collect the multivariate time series data of the overtaking operation behaviors in conditional automation driving. Driving behaviors were classified into eco‐driving operation behaviors and high fuel consumption operation behaviors based on fuel consumption calculated by using vehicle specific power (VSP). Significance analysis based on linear regression was adopted to identify operation behaviors, and an eco‐driving behavior identification model was established with the use of long short‐term memory (LSTM) for multivariate classification theory. Meanwhile, the other four classification algorithms were used to establish identification models for comparison. The results indicated that the gear position, lane position, the acceleration pedal depth, the clutch pedal depth, and the brake pedal depth had a significant influence on fuel consumption. The eco‐driving behavior identification model of overtaking demonstrated a high classification power and robustness with a classification accuracy of 89.16%. According to the simulation results, the developed adaptive identification model is with promising performance. The conclusions provide theoretical support for developing an adaptive strategy for connected eco‐driving.

A new genus of viviparid snail, Dalipaludina gen. nov., from the Yunnan Plateau of China is described within an integrative taxonomic framework based on data from the mitochondrial COI marker and morphology. Dalipaludina can be distinguished from all other viviparid genera by a unique combination shell, operculum and radula characters. Four species are assigned here to the new genus, Dalipaludina delavayana comb. nov., Dalipaludina oxytropoides comb. nov., Dalipaludina occidentalis comb. nov., and Dalipaludina pyramidella comb. nov., and one species is newly assigned to Margarya, Margarya dianchiensis comb. nov. The four species of Dalipaludina are allopatrically distributed in shallow water lentic habitats at high altitude regions of the Yunnan Plateau.

Abstract We demonstrate a method for quickly and automatically detecting all three components of a remanent magnetic field around a shielded spin-exchange relaxation-free (SERF) atomic magnetometer (AM) using the trisection algorithm (TSA) for zero-field resonance (ZFR). To satisfy the measurement of AMs, a resonance light of the 87Rb D1 line with a spectral width of less than 1MHz is converted to circular polarization by a linear polarizer and a quarter-wave plate. After the light beam has passed through the alkali metal vapor cell, the residual magnetic field can be measured by searching for triaxial ZFR optical peaks. The TSA stably reduces the measurement time to 2.41 s on average and improves the measurement accuracy, significantly outpacing existing methods. The weighted averages of all measurements with corresponding uncertainties are (−15.437 ± 0.022)nT, (6.062 ± 0.021)nT, and (−14.158 ± 0.052)nT on the x-, y-, and z-axes, respectively. These improvements could facilitate more extremely weak magnetic studies in real time, such as magnetoencephalography (MEG) and magnetocardiography (MCG) measurements.

As a clean and efficient energy, nuclear energy can replace coal for heating in winter, so as to achieve the goal of “reducing pollution and carbon” in the heating process. According to the heat supply demand index proposed by the heat supply network, based on MATLAB/Simulink simulation platform, the whole plant main system model of swimming pool-type low-temperature reactor was established, and the heat supply control scheme which can be used for reactor power regulation was put forward in this paper. The fixed value adjustment process of reactor power and the reactor response process under heat network accident conditions were analyzed in detail. The simulation results show that the control scheme can adjust the reactor power according to the fixed value demand of the heat supply network load. During the adjustment process, the main temperature parameters of the reactor are within the safety limit, and the temperature in the user room of the heat supply network can be maintained near 18 ℃. Due to the large heat capacity of the low-temperature reactor pool and there are three heat exchange circuits from the heat source to the heat network, resulting in a certain pure lag link, which makes the regulation time constant of the water supply temperature very large. At the same time, the control scheme has a certain ability to resist small load disturbance under accident conditions. In case of small load step disturbance of 2%PN caused by accidents such as fracture of heat supply network, the scheme can control the reactor power unchanged, and the temperature in the user’s room can only change within the range of 1 ℃ and be stabilized again. In addition, the control scheme can automatically trigger the flow control link of the primary circuit under the accident condition of the heat supply network, adjust the flow of the primary circuit, so that the temperature entering the reactor water tank does not exceed 68 ℃, so as to ensure that the water temperature of the water tank does not exceed the concrete temperature limit. As the primary circuit flow decreases, the core outlet temperature rises immediately. Therefore, it is necessary to place the main pump lower from the ground, so as to increase the effective NPSH (net positive suction head) of the main pump and prevent it from cavitation. In conclusion, the heating control scheme can meet the heating load demand of the heating network, maintain the stability of reactor power under the condition of small disturbance of the heating network accident, and meet the safety requirements of temperature parameters, which have a certain design reference value.

We report the highly efficient conversion of readily available biomass-derived polyols with amines to valuable furfurylamines or β-amino alcohols compounds using ruthenium catalysis. The reaction outcome is readily tuned by the simple addition of 4 ​Å molecular sieves (furfurylamines vs. β-amino alcohols) with high chemo-selectivity. The proposed reaction mechanism involves ruthenium-catalyzed hydrogen borrowing for the reduction of the imine intermediate and C–C bond cleavage of polyols via a retro-aldol process. A series of arylamines was successfully transformed into the desired products with moderate to good yields.

This paper presents a stochastic analysis of the size effect on the nominal strength of quasibrittle structures with a large preexisting notch. This type of scaling behavior has been extensively studied within a deterministic framework. Little attention is paid to stochastic analysis, which is essential for reliability-based analysis and design of engineering structures. Stochastic finite element simulations are performed to study the failure of geometrically similar beams of different sizes. The numerical analysis uses a continuum damage model, in which the tensile strength and fracture energy are modeled by homogeneous random fields. Different correlation lengths are considered as a parametric study. The analysis yields the size effects on the mean and coefficient of variation (CoV) of the nominal structural strength. It is shown that the size effect on the mean strength agrees well with the Bazant size effect model. The simulation predicts a strong size effect on the CoV of the nominal strength. Small-, intermediate-, and large-size asymptotes are derived analytically for the scaling behavior of the strength CoV. Based on these asymptotes, an approximate scaling equation is proposed for the CoV of nominal strength. The effect of the correlation length on the simulated failure behavior is discussed. [ABSTRACT FROM AUTHOR]

Cordyceps militaris polysaccharides have aroused attention due to extensive physiological activities. One novel enzymatic-extractable polysaccharide, EPCMa, was obtained by chromatography column under optimum conditions. Structural characteristics analysis indicated that EPCMa consisted of → 3)-α-L-Fucp-(1→, →4)-α-D-Glcp-(1→, →2,6)-α-D-Galp-(1→, →3)-α-Glcp-(1→, →6)-β-D-Galp-(1 → and β-D-Manp-(1 → with 20792 Da. Moreover, our work further investigated the effect of EPCMa on CCl4-indued liver injury and its underlying in mice. Results showed that EPCMa activated Nrf2 pathway by up-regulating Nrf2 and HO-1 expressions to enhance antioxidant enzymes for decreasing ROS and lipid peroxidation against oxidative stress, which inhibited NF-κB p65 and IκBα phosphorylation against the releases of IL-6, TNF-α and COX-2, thereby achieving hepatoprotective effect. To sum up, activation of Nrf2 pathway and suppression of NF-κB pathway by Nrf2/ROS/NF-κB signaling pathway are the main underlying mechanisms against CCl4-induced liver injury. These results demonstrated that EPCMa might be developed as a potential functional food and natural agent against liver injury.

Unraveling the origin of Helmholtz capacitance is of paramount importance for understanding the interfacial structure and electrostatic potential distribution of electric double layers (EDL). In this work, we combined the methods of ab initio molecular dynamics and classical molecular dynamics and modeled electrified Cu(100)/electrolyte and graphene/electrolyte interfaces for comparison. It was proposed that the Helmholtz capacitance is composed of three parts connected in series: the usual solvent capacitance, water chemisorption induced capacitance, and Pauling repulsion caused gap capacitance. We found the Helmholtz capacitance of graphene is significantly lower than that of Cu(100), which was attributed to two intrinsic factors. One is that graphene has a wider gap layer at interface, and the other is that graphene is less active for water chemisorption. Finally, based on our findings, we provide suggestions for how to increase the EDL capacitance of graphene-based materials in future work, and we also suggest that the new understanding of the potential distribution across the Helmholtz layer may help explain some experimental phenomena of electrocatalysis. [ABSTRACT FROM AUTHOR]

BackgroundThe coronavirus disease (COVID-19) pandemic has impacted HIV prevention strategies globally. However, changes in pre-exposure prophylaxis (PrEP) adherence and HIV-related behaviors, and their associations with medication adherence among men who have sex with men (MSM) PrEP users remain unclear since the onset of the COVID-19 pandemic.MethodsA Retrospective Cohort Study of HIV-negative MSM PrEP users was conducted in four Chinese metropolises from December 2018 to March 2020, assessing the changes in PrEP adherence and HIV-related behaviors before and during the COVID-19. The primary outcome was poor PrEP adherence determined from self-reported missing at least one PrEP dose in the previous month. We used multivariable logistic regression to determine factors correlated with poor adherence during COVID-19.ResultsWe enrolled 791 eligible participants (418 [52.8%] in daily PrEP and 373 [47.2%] in event-driven PrEP). Compared with the data conducted before the COVID-19, the proportion of PrEP users decreased from 97.9 to 64.3%, and the proportion of poor PrEP adherence increased from 23.6 to 50.1% during the COVID-19 [odds ratio (OR) 3.24, 95% confidence interval (CI) 2.62–4.02]. While the percentage of condomless anal intercourse (CAI) with regular partners (11.8 vs. 25.7%) and with casual partners (4.4 vs. 9.0%) both significantly increased. The proportion of those who were tested for HIV decreased from 50.1 to 25.9%. Factors correlated with poor PrEP adherence during the COVID-19 included not being tested for HIV (adjusted odds ratio [aOR] = 1.38 [95% CI: 1.00, 1.91]), using condoms consistently with regular partners (vs. never, aOR = 2.19 [95% CI: 1.16, 4.13]), and being married or cohabitating with a woman (vs. not married, aOR = 3.08 [95% CI: 1.60, 5.95]).ConclusionsIncreased poor PrEP adherence and CAI along with the decrease in HIV testing can lead to an increase in HIV acquisition and drug resistance to PrEP. Targeted interventions are needed to improve PrEP adherence and HIV prevention strategies.

It is worth understanding the potentials of zero charge (PZCs) and structures of stepped metal/water interfaces, because for many electrocatalytic reactions, stepped surfaces are more active than atomically flat surfaces. Herein, a series of stepped Pt/water interfaces are modeled at different step densities with ab initio molecular dynamics. It is found that the structures of Pt/water interfaces are significantly influenced by the step density, particularly in regard to the distribution of chemisorbed water. The step sites of metal surfaces are more preferred for water chemisorption than terrace sites, and until the step density is very low, water will chemisorb on the terrace. In addition, it is revealed that the PZCs of stepped Pt/water interfaces are generally smaller than that of Pt(111), and the difference is mainly attributed to the difference in their work function, providing a simple way to estimate the PZCs of stepped metal surfaces. Finally, it is interesting to see that the Volta potential difference is almost the same for Pt/water interfaces with different step densities, although their interface structures and magnitude of charge transfer clearly differ. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is a kind of lung disease with acute dyspnea, pulmonary inflammation, respiratory distress, and non-cardiogenic pulmonary edema, accompanied by the mid- and end-stage characteristics of COVID-19, clinically. It is imperative to find non-toxic natural substances on preventing ALI and its complications. The animal experiments demonstrated that Lentinus edodes polysaccharides (PLE) had a potential role in alleviating ALI by inhibiting oxidative stress and inflammation, which was manifested by reducing the levels of serum lung injury indicators (C3, hs-CRP, and GGT), reducing the levels of inflammatory factors (TNF-α, IL-1β, and IL-6), and increasing the activities of antioxidant enzymes (SOD and CAT) in the lung. Furthermore, PLE had the typical characteristics of pyran-type linked by β-type glycosidic linkages. The conclusions indicated that PLE could be used as functional foods and natural drugs in preventing ALI.

The present work was aimed to investigate the protective effects of enzymatic-hydrolyzed Auricularia polytricha polysaccharides (EnAPS) on renal functions. The characterizations were analyzed by physicochemical methods, and the renoprotections were processed in adenine-induced chronic kidney diseases (CKD) models of mice. Animal experiments exhibited that EnAPS showed superior renal-protections contributing to its antioxidant effects of increasing the enzyme activities and decreasing the lipid contents, and anti-inflammatory effects of reducing proinflammatory cytokines than A. polytricha polysaccharides (APS). Besides, the anti-apoptosis effects of EnAPS was proved by down-regulating Bax and Caspase-3 expressions and up-regulating Bcl-2 expressions by molecular biotechnology, and the anti-fibrosis effects was confirmed by histopathological observations of staining. The characterizations indicated that lower molecular weights possibly contributed to the superior renoprotective effects. These results suggested that enzymatic hydrolysis had potential effects in enhancing the bioactivities, and the polysaccharides could be used in the development of functional foods supplement against CKD.

Helicostoa sinensis E. Lamy, 1926 is a unique freshwater gastropod species with a sessile habit. This enigmatic species was first found cemented on river limestones from China about 120 years ago and described together with the genus. It was never collected again and has been considered monotypic. Here, we report the rediscovery of Helicostoa from several rivers in China, and describe a second species of this genus based on a comprehensive study. In addition to the unique sessile habit of both species, the new Helicostoa species presents one of the most remarkable cases of sexual dimorphism within molluscs. Only the adult female is sessile and the original aperture of the female is sealed by shell matter or rock, while an opening on the body whorl takes the function of the original aperture. The male is vagile, with a normal aperture. Our results confirm the recently suggested placement of Helicostoa within the family Bithyniidae. The sessility of Helicostoa species is considered as an adaption to the limestone habitat in large rivers. The extreme sexual dimorphism and secondary aperture of females are considered as adaptations to overcome the obstacles for mating and feeding that come with a sessile life style. [ABSTRACT FROM AUTHOR]

The field density of as-constructed asphalt pavements usually exhibits considerable variability. Understanding and quantifying this variability is of crucial importance for building more reliable and durable pavements. This study investigates the probability distribution of the field density based on an analytical model of gyratory compaction. The model is derived from mass balance and the transition state theory for the process of aggregate rearrangement. Meanwhile, the variability in the compaction effort is also taken into account. The model is first calibrated by the laboratory gyratory compaction experiments, and is then used to predict the probability distribution of the field density, which is compared with field measurements. It is shown that the probabilistic model can capture the left-skewed and leptokurtic features of the field density distribution. The present model surpasses the commonly used Gaussian distribution for characterising the field density distribution. A parametric study is performed to investigate the effects of the compaction properties of mixture and field compaction effort on the probability distribution of the field density. The model can potentially be used to guide the asphalt mix design for achieving the desired field density. [ABSTRACT FROM AUTHOR]

Abstract Background Glioma is a common brain tumor with a high mortality rate. A small population of cells expressing stem-like cell markers in glioma contributes to drug resistance and tumor recurrence. Methods Porous silicon nanoparticles (PSi NPs) as photothermal therapy (PTT) agents loaded with TMZ (TMZ/PSi NPs), was combined with hyperbaric oxygen (HBO) therapy in vitro and in vivo. To further investigate underlying mechanism, we detected the expression of stem-like cell markers and hypoxia related molecules in vitro and in vivo after treatment of TMZ/PSi NPs in combination with PTT and HBO. Results NCH-421K and C6 cells were more sensitive to the combination treatment. Moreover, the expression of stem-like cell markers and hypoxia related molecules were decreased after combination treatment. The in vivo results were in line with in vitro. The combination treatment presents significant antitumor effects in mice bearing C6 tumor compared with the treatment of TMZ, PTT or TMZ/PSi NPs only. Conclusion These results suggested the TMZ/PSi NPs combined with HBO and PTT could be a potential therapeutic strategy for glioma.