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Serverless computing is a promising paradigm that greatly simplifies cloud programming. With serverless computing, developers simply provide event-driven functions to a serverless platform, and these functions can be orchestrated as serverless workflows to accomplish complex tasks. Due to the lightweight limitation of functions, serverless workflows not only suffer from existing vulnerability-based threats but also face new security threats from the function compiling phase. In this paper, we present SMWE, a secure and makespan-oriented workflow execution framework in serverless computing. SMWE enables all life cycle protection for functions by adopting compiler shifting and running environment replacement in the serverless workflow. Furthermore, SMWE balances the tradeoff between security and makespan by carefully scheduling functions to running environments and selectively applying the secure techniques to functions. Extensive evaluations show that SMWE significantly increases the security of serverless workflows with small makespan cost. [ABSTRACT FROM AUTHOR]

The hybrid system can extend the range of special vehicles and meet the electrical requirements of on-board equipment. In this paper, the driving force plummet problem of a new two-gear power-split hybrid system was studied during gear switches in a hybrid mode. The dynamic model of a hybrid electric system was established, and the effects of the engine angular acceleration and angular jerk on vehicle power and ride performance were obtained. The optimal ratio of the torque change rate of the motor and engine in the mode switch process was proposed. Considering the battery limitation and the external characteristics of the engine, the method of determining the target speed of the engine during shifting was proposed. Considering the response characteristics of each power source, the dynamic coordinated control strategy of multiple power sources in the mode switch process was proposed. The vehicle dynamics model was established based on the Matlab/Simulink 2020b and verified by simulation and a hardware-in-the-loop (HIL) test. The results show that the dynamic coordinated control strategy can reduce the peak impact by 80.33%, effectively improve the vehicle power and ride performance, and prevent the occurrence of high-current battery charging. [ABSTRACT FROM AUTHOR]

As a highly economic berry fruit crop, blueberry is enjoyed by most people and has various potential health benefits, many of which are attributed to the relatively high concentrations of flavonoids. To obtain more accurate and comprehensive transcripts, the full-length transcriptome of half-highbush blueberry (Vaccinium corymbosum/angustifolium cultivar Northland) obtained using single molecule real-time and next-generation sequencing technologies was reported for the first time. Overall, 147,569 consensus transcripts (average length, 2738 bp; N50, 3176 bp) were obtained. After quality control steps, 63,425 high-quality isoforms were obtained and 5030 novel genes, 3002 long non-coding RNAs, 3946 transcription factor genes (TFs), 30,540 alternative splicing events, and 2285 fusion gene pairs were identified. To better explore the molecular mechanism of flavonoid biosynthesis in mature blueberry fruit, an integrative analysis of the metabolome and transcriptome was performed on the exocarp, sarcocarp, and seed. A relatively complete biosynthesis pathway map of phenylpropanoids, flavonoids, and proanthocyanins in blueberry was constructed. The results of the joint analysis showed that the 228 functional genes and 42 TFs regulated 78 differentially expressed metabolites within the biosynthesis pathway of phenylpropanoids/flavonoids. O2PLS analysis results showed that the key metabolites differentially accumulated in blueberry fruit tissues were albireodelphin, delphinidin 3,5-diglucoside, delphinidin 3-O-rutinoside, and delphinidin 3-O-sophoroside, and 10 structural genes (4 Vc4CLs, 3 VcBZ1s, 1 VcUGT75C1, 1 VcAT, and 1 VcUGAT), 4 transporter genes (1 VcGSTF and 3 VcMATEs), and 10 TFs (1 VcMYB, 2 VcbHLHs, 4 VcWD40s, and 3 VcNACs) exhibited strong correlations with 4 delphinidin glycosides. These findings provide insights into the molecular mechanisms of flavonoid biosynthesis and accumulation in blueberry fruit. [ABSTRACT FROM AUTHOR]

A catalyst-free aza-Michael addition/C(sp3)-O bond formation tandem reaction of substituted amino ferrocenes with quinone esters was developed, which provided a green and efficient strategy for the construction of a C(sp3)-O bond from C(sp3)-H, and a series of N-ferrocene-substituted benzodihydrooxazoles were smoothly produced in moderate to excellent yields (up to >99% yield). The mechanism experiments showed that quinone esters performed as both substrate and oxidant. The salient features of this transformation include good functional group tolerance, broad substrate scope and mild conditions. [ABSTRACT FROM AUTHOR]

"Blind holes" are the main reasons for the reduced performance of microgas sensor carriers. To improve the "blind hole" of catalytic combustion methane sensors and therefore, their thermal stability, this study presents a numerical simulation of the catalytic combustion in an Al2O3− oriented ceramic array involving porous microthermal plates. A three-visualization model of the sensor is established using the FLUENT software, and the simulation results are systematically analyzed based on the dynamics and thermodynamic mechanism of the microgas sensor. The results show that the regularity of the surface reaction presents a circular distribution, with the center line of the channel serving as the axis symmetry. The total reaction velocity in the array hole increases gradually from the inlet to the outlet. The flow velocity at the inlet should be controlled at more than 1 × 10−8 m/s, which is more accurate compared with the concept of "uniform velocity" in previous studies. The optimum pore size at the inlet should be 150 nm, and the inner pore size of the wall should be slightly higher than 300 nm, which is a more careful division compared with previous pore-size studies. The efficient reaction position is from the inlet to the quarter of the hole. The simulation results make up for the deficiencies in the analysis of the process parameters of the methane sensor carrier array hole and the internal reaction change process, as well as provide innovative comments on the sensor structure design. Through digital simulations, the limitations associated with the experiments can be avoided, the theoretical study can be improved, theoretical support can be provided for experiments related to the improvement of thermal stability, the predictability of experiments can be improved, and the feasibility of the research proposal can be verified. These steps are important for the improvement of the "blind hole" problem of catalytic combustion methane sensors. [ABSTRACT FROM AUTHOR]

Sentiment analysis of subjective texts in social media is beneficial to help people adjust and intervene in a negative mental state in time, which is significant to mental health care. At present, limited by the accuracy of word segmentation, sentiment analysis of subjective text has difficulties in dealing with context, sentence patterns, and word co-occurrence. This paper aims to propose an efficient method of semantic feature representation and sentiment analysis, thereby providing a basis for sentiment visualization and interactive applications. Based on Ernie-Tiny and BiGRU, this paper proposes a sentiment analysis model ET_s_BG+p to solve problems in analyzing Chinese subjective texts' complex semantics, diverse sentence patterns, and shortness. The model inputs the semantic features obtained via Ernie-Tiny into BiGRU and then splices the output with the sentence vectors of Ernie-Tiny to form final text features and perform sentiment classification. Experiments are performed on a dataset integrating text comments from Weibo, takeaway, and e-commerce platforms. The results show that the model proposed in this paper performs best in most of the evaluation indicators compared with baseline models such as CNN, BiLSTM, and GRU. The experiments show that the accuracy of the model on the dataset built in this research is 84.30%, the precision is 83.95%, the recall rate is 88.35%, and the F1 value is 85.98%. At the same time, based on ET_s_BG+p, this paper develops a prototype visual display platform that integrates functions such as text input, sentiment analysis, and agent interaction, which can provide support for daily emotion monitoring and adjustment. [ABSTRACT FROM AUTHOR]

Drought is the main abiotic stress limiting soybean production worldwide and seriously limits the reproductive growth of soybean. To elucidate the molecular mechanisms of drought stress response in soybean seed developmental stages, transcriptome analysis was performed on five seed developmental stages under drought stress and control conditions. Thousands of genes were found to change in expression level under drought stress, GO and KEGG enrichment analysis showed that differentially expressed genes (DEGs) were involved in drought resistance at every stage or tissue, but there were very few DEGs at the primary stage of seed development, which indicated that the seeds at the primary developmental stage were influenced little by drought stress. There was no shared DEG among all five stages or tissues, this indicated that they have different mechanisms to resist drought stress. Furthermore, we investigated DEGs associated with drought response at different stages to identify candidate regulators of drought stress response during soybean seed development. These genes are associated with metabolic and regulatory networks, among others. Taken together, the results will expand our understanding of the adaptation of soybean to drought stress and provide new insights into the molecular mechanisms of soybean drought tolerance development. [ABSTRACT FROM AUTHOR]

In order to improve the response characteristics of the surface acoustic wave (SAW) sensor to trace gases, a SAW CO gas sensor based on a Pd–Pt/SnO2/Al2O3 film with a high-frequency response performance is proposed in this paper. The gas sensitivity and humidity sensitivity of trace CO gas are tested and analyzed under normal temperatures and pressures. The research results show that, compared with the frequency response of the Pd–Pt/SnO2 film, the CO gas sensor based on a Pd–Pt/SnO2/Al2O3 film has a higher frequency response performance, and the sensor has high-frequency response characteristics to CO gas with a concentration in the range of 10–100 ppm. The average response recovery time of 90% ranges from 33.4 s to 37.2 s, respectively. When the CO gas with a concentration of 30 ppm is tested repeatedly, its frequency fluctuation is less than 5%, indicating that the sensor has good stability. In the range of relative humidity (RH) from 25% to 75%, it also has high-frequency response characteristics for CO gas with a 20 ppm concentration. [ABSTRACT FROM AUTHOR]

To improve household air quality, the Chinese government has launched a number of pilot stove renovation projects, but few studies have explored the impact of the project on people's perception of and willingness to participate in these renovations; moreover, factors affecting willingness to pay for the project in rural China are not yet clear. We conducted a field measurement and a corresponding door-to-door questionnaire survey using the renovated group and the unrenovated group. The results showed that (1) the stove renovation project could not only reduce PM2.5 exposure and the excess mortality risk of rural residents, but also (2) improve residents' risk perception and self-protective willingness. (3) Specifically, the project had a deeper impact on female and low-income residents. (4) Meanwhile, the higher the income and the larger family size, the higher the risk perception and self-protective willingness. (5) Furthermore, willingness to pay for the project was related with residents' support for the project, benefit from renovation, income, and family size. Our results recommended that stove renovation policies should pay more attention to families with lower income and smaller size. [ABSTRACT FROM AUTHOR]

Surface Acoustic Wave (SAW) methane-sensing technology is a new way to detect methane at room temperature. However, the material and structure of the sensitive film are the important factors affecting the detection performance of the sensor. In this paper—with a SAW methane sensor using graphene–nickel cavitation—a composite film is proposed, which can work at room temperature. A delay linear dual-channel differential oscillator with center frequency of 204.3 MHz and insertion loss of −5.658 dB was designed; Cryptophane-A material was prepared by the "three-step method". The composite sensitive film was synthesized by a drop coating method, electrochemical deposition method and electroplating method. The composite film was characterized by SEM. The sensor performance test system and gas sensitivity test system were constructed to determine the response performance of the sensor at concentrations of 0~5% CH4. The results showed that the sensor had a good response recovery performance in the test concentration range, and the frequency offset was positively correlated with methane concentration. The 90% average response time and recovery times were 41.2 s and 57 s, respectively. The sensor sensitivity was 809.4 ± 6.93 Hz/(1% CH4). This study provides a good theoretical basis for the development of surface acoustic-wave methane sensors. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising future fuel to enable the transition of transportation sector toward carbon neutrality. The direct utilization of H2 in internal combustion engines (ICEs) faces three major challenges: high NOx emissions, severe pressure rise rates, and pre-ignition at mid to high loads. In this study, the potential of H2 combustion in a truck-size engine operated in spark ignition (SI) and pre-chamber (PC) mode was investigated. To mitigate the high pressure rise rate with the SI configuration, the effects of three primary parameters on the engine combustion performance and NOx emissions were evaluated, including the compression ratio (CR), the air–fuel ratio, and the spark timing. In the simulations, the severity of the pressure rise was evaluated based on the maximum pressure rise rate (MPRR). Lower compression ratios were assessed as a means to mitigate the auto-ignition while enabling a wider range of engine operation. The study showed that by lowering CR from 16.5:1 to 12.5:1, an indicated thermal efficiency of 47.5% can be achieved at 9.4 bar indicated mean effective pressure (IMEP) conditions. Aiming to restrain the auto-ignition while maintaining good efficiency, growth in λ was examined under different CRs. The simulated data suggested that higher CRs require a higher λ, and due to practical limitations of the boosting system, λ at 4.0 was set as the limit. At a fixed spark timing, using a CR of 13.5 combined with λ at 3.33 resulted in an indicated thermal efficiency of 48.6%. It was found that under such lean conditions, the exhaust losses were high. Thus, advancing the spark time was assessed as a possible solution. The results demonstrated the advantages of advancing the spark time where an indicated thermal efficiency exceeding 50% was achieved while maintaining a very low NOx level. Finally, the optimized case in the SI mode was used to investigate the effect of using the PC. For the current design of the PC, the results indicated that even though the mixture is lean, the flame speed of H2 is sufficiently high to burn the lean charge without using a PC. In addition, the PC design used in the current work induced a high MPRR inside the PC and MC, leading to an increased tendency to engine knock. The operation with PC also increased the heat transfer losses in the MC, leading to lower thermal efficiency compared to the SI mode. Consequently, the PC combustion mode needs further optimizations to be employed in hydrogen engine applications. [ABSTRACT FROM AUTHOR]

Soybeans are essential crops that supply protein and oil. The composition and contents of soybean fatty acids are relevant to human health and have a significant relationship with soybean oil processing and applications. Identifying quantitative trait locus (QTL) genes related to palmitic acid could facilitate the development of a range of nutritive soybean cultivars using molecular marker-assisted selection. In this study, we used a cultivar with higher palmitic acid content, 'Dongnong42', and a lower palmitic acid content cultivar, 'Hobbit', to establish F2:6 recombinant inbred lines. A high-density genetic map containing 9980 SLAF markers was constructed and distributed across 20 soybean chromosomes. The genetic map contained a total genetic distance of 2602.58 cM and an average genetic distance of 0.39 cM between adjacent markers. Two QTLs related to palmitic acid content were mapped using inclusive composite interval mapping, explaining 4.2–10.1% of the phenotypic variance in three different years and environments, including the QTL included in seed palmitic 7-3, which was validated by developing SSR markers. Based on the SNP/Indel and significant differential expression analyses of Dongnong42 and Hobbit, two genes, Glyma.15g119700 and Glyma.15g119800, were selected as candidate genes. The high-density genetic map, QTLs, and molecular markers will be helpful for the map-based cloning of palmitic acid content genes. These could be used to accelerate breeding for high nutritive value cultivars via molecular marker-assisted breeding. [ABSTRACT FROM AUTHOR]

In order to further improve the degree of frequency response of the surface acoustic wave (SAW) sensor for gas detection, the structure of the forked-finger transducer was analyzed, and its optimal structural parameters were simulated and designed. The simulation model of the unidirectional fork-finger transducer is established by using COMSOL finite element software. The thickness of the piezoelectric substrate, the electrode structure and material, and the thickness of the coating film are optimized and simulated. The results show that: the optimal thickness of the piezoelectric substrate is 3λ. The optimal thickness ratio and the lay-up ratio of the forked-finger electrode are 0.02 and 0.5, respectively. The Al electrode is more suitable as the a forked-finger electrode material compared to Cu, Au and Pt materials. Under the same conditions, the metal oxide-sensitive film (ZnO and TiO2) has a higher frequency response than the polymer-sensitive film (polyisobutylene and polystyrene), and the best sensitive film thickness range is 0.5~1 μm. [ABSTRACT FROM AUTHOR]

Heinong 84 is one of the major soybean varieties growing in Northeast China, and is resistant to the infection of all strains of soybean mosaic virus (SMV) in the region including the most prevalent strain, N3. However, the resistance gene(s) in Heinong 84 and the resistant mechanism are still elusive. In this study, genetic and next-generation sequencing (NGS)-based bulk segregation analysis (BSA) were performed to map the resistance gene using a segregation population from the cross of Heinong 84 and a susceptible cultivar to strain N3, Zhonghuang 13. Results show that the resistance of Heinong 84 is controlled by a dominant gene on chromosome 13. Further analyses suggest that the resistance gene in Heinong 84 is probably an allele of Rsv1 . Finally, two pairs of single-nucleotide-polymorphism (SNP)-based primers that are tightly cosegregated with the resistance gene were designed for rapidly identifying resistant progenies in breeding via the cleaved amplified polymorphic sequence (CAPS) assay.

Aiming at solving the slow-response problem of traditional bead-type thermal conductivity gas sensors, a fast-response thermal conductivity gas sensor can be made by using multiwalled carbon nanotubes (MWNTs), combined with the technology of carrier modification, to modify the performance of the sensor carrier. The carrier material, granular nanoscale γ-Al₂O₃/ZrO₂, was synthesized by chemical precipitation, and its particle size was found to be 50⁻70 nm through SEM. After the carrier material was wet-incorporated into carbon nanotubes, the composite carrier γ-Al₂O₃/ZrO₂/MWNTs was obtained. The results show that the designed thermal conductivity sensor has a fast response to methane gas, with a 90% response time of 7 s and a recovery time of 16 s. There is a good linear relationship between the sensor output and CH₄ gas concentration, with an average sensitivity of 1.15 mV/1% CH₄. Thus, the response speed of a thermal conductivity sensor can be enhanced by doping carbon nanotubes into γ-Al₂O₃/ZrO₂.