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Study region: Inner Mongolia Autonomous Region, North China Study focus: Sensible heat flux (H) quantifies the intensity of water evapotranspiration, making the factors influencing H pivotal to water consumption. North China's semi-arid grasslands are characterized by widespread grazing and strong wind conditions. Grazing strategy modifies surface air heat transfer resistance via vegetation and consequently alters H. Nevertheless, the majority of studies overlook the impact of the observed variables' time scale on H estimation. This paper employs a ''big-leaf'' model to estimate H, incorporating both grazing management strategy and data time scale, validated using the Bowen ratio, and attempted to analyze the factors that affect H. New hydrological insights for the region: Aerodynamic characteristics estimated from daily data typically exceed estimates derived from hourly data. The influence of surface radiative temperature and air temperature on H outweighs that of aerodynamic resistance, whereas aerodynamic resistance accounts for the disparity in estimating H between daily and hourly data. In grazing-prohibited grasslands, the daily H values estimated by the Big Leaf model closely match those obtained from the Bowen ratio. When estimating the hourly H value for grazing prohibited and grazing grasslands, the increase was 25.95 w/m2 and 52.27 w/m2 compared to the daily scale, respectively. For the estimation of water and heat fluxes across different regions, the temporal scale of input data is a pivotal factor.

Abstract Due to the alternating loads on pumping units and the integration of new energy sources, multisource DC microgrid pumping unit well groups experience increased fluctuations in voltage and power as well as superimposed peak and valley values. This work presents a distributed control strategy for pumping unit well groups on a multisource DC microgrid based on the weighted moving average algorithm. A centralized control program is implanted in the RTU of the single-well controller of each pumping unit, and communication with each well is realized via SCADA and multicast communication, resulting in a distributed well group system. The real-time power values of the pumping well group are calculated by grouping the power values, and each group is weighted using the total power fluctuation threshold of the well group as the control target. Then, a weighted moving average algorithm is used to predict the next power value and form a table of predicted real-time power spectra. According to the power values in the community power spectrum table, the inverter frequency is proportionally adjusted downwards to reach the power peak before deceleration; after the power peak is crossed, the frequency is increased in the same way to reach the power valley before acceleration. Finally, the peak and valley power values of the bus system level off and further learn to reach the set impulse; ultimately, a stable impulse is formed. In laboratory testing and field application in the Shengli Oilfield XIN-11 block, the group control software module effectively suppressed the active power peak and valley values and voltage fluctuations of the bus system, the active power fluctuation rate range decreased by more than 70%, and the DC bus voltage fluctuation range decreased by more than 80%; moreover, the active power decreased by approximately 6% without additional hardware costs.

Abstract Background The intestine of young ruminants is in the developmental stage and has weaker resistance to the changes of external environment. Improving intestinal health is vital to promoting growth of young ruminants. This study investigated effects of guanidino acetic acid (GAA) and rumen‐protected betaine (RPB) supplementation on growth, dietary nutrient digestion and GAA metabolism in the small intestine of sheep. Methods Eighteen healthy Kazakh rams (27.46 ± 0.10 kg of body weight and 3‐month old) were categorized into control, test group I and test group II, which were fed a basal diet, 1500 mg/kg GAA and 1500 mg/kg GAA + 600 mg/kg RPB, respectively. Results Compared with control group, test group II had increased (p

Abstract Lysosomes are essential components for managing tumor microenvironment and regulating tumor growth. Moreover, recent studies have also demonstrated that long non-coding RNAs could be used as a clinical biomarker for diagnosis and treatment of colorectal cancer. However, the influence of lysosome-related lncRNA (LRLs) on the progression of colon cancer is still unclear. This study aimed to identify a prognostic LRL signature in colon cancer and elucidated potential biological function. Herein, 10 differential expressed lysosome-related genes were obtained by the TCGA database and ultimately 4 prognostic LRLs for conducting a risk model were identified by the co-expression, univariate cox, least absolute shrinkage and selection operator analyses. Kaplan–Meier analysis, principal-component analysis, functional enrichment annotation, and nomogram were used to verify the risk model. Besides, the association between the prognostic model and immune infiltration, chemotherapeutic drugs sensitivity were also discussed in this study. This risk model based on the LRLs may be promising for potential clinical prognosis and immunotherapeutic responses related indicator in colon cancer patients.

Evaluating aviation emissions and examining the dispersion properties of contaminants are crucial for understanding atmospheric pollution. To assess the pollutant emissions and dispersion of aircraft during the landing and takeoff (LTO) cycle, and address air pollution surrounding the airport resulting from flight operations, this study evaluated emissions throughout the LTO phase based on Quick Access Recorder (QAR) data in conjunction with the first-order approximation method. An improved Gaussian diffusion model for mobile point sources was employed to examine the diffusion characteristics of contaminants. Additionally, CFD calculation outcomes for various exhaust velocities and wind speeds were utilized to validate the trustworthiness of the improved Gaussian model. The discussion also encompasses the influence of diffusion time, wind direction, wind speed, temperature gradient, and particle deposition on the concentration distribution of contaminants. The findings indicated that the Gaussian diffusion model aligned with the results of the CFD calculations. The diffusion distribution of contaminants around airports varies over time and is significantly influenced by atmospheric environmental factors, including wind direction, wind speed, and atmospheric stability. Specifically, a change in wind direction from 0° to 45° caused a shift of approximately 1000 m in the contaminant’s center. An increase in wind speed from 3 m/s to 5 m/s led to a decrease in concentration by about 15%. Furthermore, a transition in atmospheric stability from category ‘a’ (very unstable) to ‘f’ (very stable) resulted in a two-order-of-magnitude increase in contaminant concentrations.

Abstract Cellular activities are carried out vastly by protein complexes but large repertoire of protein complexes remains functionally uncharacterized which necessitate new strategies to delineate their roles in various cellular processes and diseases. Thermal proximity co-aggregation (TPCA) is readily deployable to characterize protein complex dynamics in situ and at scale. We develop a version termed Slim-TPCA that uses fewer temperatures increasing throughputs by over 3X, with new scoring metrics and statistical evaluation that result in minimal compromise in coverage and detect more relevant complexes. Less samples are needed, batch effects are minimized while statistical evaluation cost is reduced by two orders of magnitude. We applied Slim-TPCA to profile K562 cells under different duration of glucose deprivation. More protein complexes are found dissociated, in accordance with the expected downregulation of most cellular activities, that include 55S ribosome and respiratory complexes in mitochondria revealing the utility of TPCA to study protein complexes in organelles. Protein complexes in protein transport and degradation are found increasingly assembled unveiling their involvement in metabolic reprogramming during glucose deprivation. In summary, Slim-TPCA is an efficient strategy for characterization of protein complexes at scale across cellular conditions, and is available as Python package at https://pypi.org/project/Slim-TPCA/ .

Conservation tillage technology possesses substantial potential to enhance agricultural production efficiency and tackle issues such as wind erosion and land degradation in semi-arid regions. The integration of no-tillage and straw mulching technologies in the conventional aeolian semi-arid agricultural zones of western Liaoning, China, has led to notable improvements in crop yield and soil quality. However, a comprehensive assessment of the mechanisms and kinetics involved in soil nutrient variations is yet to be conducted. During a two-year study period, we assessed four tillage systems in the aeolian semi-arid regions of Northern China: no-tillage with full straw mulching (NTFS), no-tillage with half straw mulching (NTHS), no-tillage without straw mulching (NT), and conventional tillage (CT). The investigation focused on examining nutrient conditions, enhancing photosynthetic activity, and increasing maize yield while improving water use efficiency (WUE). Our findings emphasize the beneficial impact of combining no-tillage and straw mulching on enhancing soil water retention, resulting in a notable rise in soil moisture levels during the crucial growth phases of maize. This approach also positively influenced soil nutrient levels, particularly in the 0–20 cm layer, fostering an environment conducive to maize cultivation. In terms of ecological benefits, no-tillage with straw mulching curtailed soil sediment transport and wind erosion, notably at 30–40 cm heights, aiding in the ecological protection of the region. The yield and WUE were substantially higher under NTFS and NTHS than under CT, with NTHS demonstrating the most significant gains in yield (14.5% to 16.6%) and WUE (18.3% to 21.7%) throughout the study period. A TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) analysis confirmed NTHS as the optimal treatment, achieving the highest scores for soil water, nutrient availability, wind erosion control, maize photosynthesis, yield, and WUE, thus emerging as the most effective conservation tillage strategy for sustainable agriculture in aeolian semi-arid regions.

Whether the self-demodulation of mechanism interference can be realized in the self-driven execution process of filling operation is the basis for the solid filling hydraulic support to achieve intelligence. Using the theoretical analysis method, taking the ZC5 160/30/50 type solid filling hydraulic support as an example, starting from the geometric and motion constraint relationship of the filling support mechanism, the orthogonal pose control index is established: the horizontal distance and vertical distance of the tamping hinge point top beam, which realizes the pose characterization of the rear top beam of the support under any working condition; The motion characteristics of the bottom-discharge conveyor of the filling support under various working condition factors were analyzed, and the orthogonal pose control index was established: the vertical distance and horizontal distance of the top beam of the bottom-discharge conveyor, which realized the pose characterization of the bottom-discharge conveyor under any working condition; Based on the pose control index of the rear top beam and the bottom-discharge conveyor, the landing position characterization index of the filling material on the coal seam floor during the discharge process is further obtained: the discharge center distance, which realizes the landing position characterization of the filling material under any working condition; the connection relationship and easy interference position of the mechanism action and pose adjustment in each stage of the filling operation process are analyzed, based on the orthogonal pose control index, the interference critical control equation of the discharge and typical collision position under any working condition is established by using the projection method; taking the tamping mechanism rotation angle and tamping cylinder stroke as the characterization of the interference critical curve under typical working conditions, it is proposed to use the three-zone distribution characteristics of “interference zone, easy interference zone, and non-interference zone” to characterize the interference critical degree, and give the demodulation path of each interference state; based on the interference critical control equation, interference three-zone distribution characteristics and the connection relationship of mechanism action and pose adjustment in the filling operation process, an interference state autonomous identification method is proposed: using angle sensor and stroke sensor to obtain the real-time rotation angle and stroke of the tamping mechanism, substituting into the interference critical equation of each easy interference position to obtain the theoretical value and interference critical curve of the tamping mechanism rotation angle or stroke in that position, judging the position of the actual value on the interference critical curve three-zone distribution diagram can realize the autonomous discrimination of interference position and state, and autonomous demodulation can be realized according to the interference three-zone distribution curve diagram; based on the interference position and interference state autonomous identification method, the interference autonomous discrimination and demodulation algorithm is designed. The research results provide new reference indicators for the pose characterization of the filling hydraulic support mechanism, provide basic criteria for the intelligent obstacle avoidance and demodulation of mechanism interference, and provide algorithm basis for the self-driven execution of the filling operation of solid intelligent filling.

With the aim of addressing the visual positioning problem of board-to-board (BTB) jacks during the automatic assembly of flexible printed circuit (FPC) in mobile phones, an FPC-BTB jack detection method based on the optimized You Only Look Once, version 5 (YOLOv5) deep learning algorithm was proposed in this study. An FPC-BTB jack real-time detection and positioning system was developed for the real-time target detection and pose output synchronization of the BTB jack. On that basis, a visual positioning experimental platform that integrated a UR5e manipulator arm and Hikvision industrial camera was built for BTB jack detection and positioning experiments. As indicated by the experimental results, the developed FPC-BTB jack detection and positioning system for BTB target recognition and positioning achieved a success rate of 99.677%. Its average detection accuracy reached 99.341%, the average confidence of the detected target was 91%, the detection and positioning speed reached 31.25 frames per second, and the positioning deviation was less than 0.93 mm, which conforms to the practical application requirements of the FPC assembly process.

The fluidic pintle nozzle, a new method to control the thrust of a solid rocket motor, has been proposed in recent years by combining the pintle with the aerodynamic throat (fluidic throat). The study of static characteristics has proved that it has a remarkable effect on thrust control. To study the transient characteristics of the fluidic pintle nozzle, 2D transient simulations of a fluidic pintle nozzle propulsion system were conducted, employing dynamic meshing techniques. The Reynolds-averaged Navier–Stokes equations were meticulously solved, implementing a k–ω SST turbulence model. The thrust control principle of the fluid pintle nozzle was studied, and the wave structure was summarized. The transient characteristics of the secondary flow opening, secondary flow closing, pintle moving forward (pressure rise), and pintle moving backward (pressure drop) were obtained, and the effects of the injection angle and injection port position were studied. The response process after injection can be roughly divided into three stages: pressure propagation, pressure oscillation, and equilibrium stability, with time distributions of 0.4%, 5.39%, and 94.21%, respectively. In the process of the pintle moving forward, the rate of combustion chamber pressure increases and thrust decreases gradually because of the arc wall of the nozzle throat upstream, and the process of throats moving backward is just the opposite. Compared with the condition with a maximum throat opening and no secondary flow, the thrust of the condition with a minimum throat opening and a 0.3-flow-ratio secondary flow is increased by 80.95%. Under conditions of constrained flow ratio, the injection angle of the secondary flow ostensibly exerts negligible influence on the dynamic modulation of thrust. Nevertheless, it remains evident that a reduction in throat opening accentuates the impact of reverse injection. Furthermore, the proximity of the injection port to the head of the pintle is directly proportional to the efficacy of thrust control.

A satellite with two solar wings can be modeled using a pair of symmetric flexible cantilever beams connected to a central rigid body. Due to certain reasons, the symmetric flexible cantilever beams may be turned into asymmetric ones, which will inevitably influence the vibration properties of the structural system. By changing the structural sizes and adding local mass on one side of the two beams, a structural system with asymmetric mass distribution is obtained and its vibration characteristics are investigated. Hamilton’s principle with the assumed mode method is employed to establish the equation of motion of the asymmetric structural system. The natural frequencies, mode shapes, frequency response curves and displacement time histories of the system are calculated, and they are compared with those of the structural system with a symmetric mass distribution. The correctness and feasibility of the present analytical method are verified by means of the finite element method (FEM) and a vibration experiment. The analytical results show that the mass asymmetry of the two beams leads to the mode localization phenomenon, and the coupling effect between the two beams and the central rigid body is enhanced. The larger the mass asymmetry is and the closer the position of the added local mass to the end of the cantilever beam is, the more obvious of the mode localization phenomenon is and the more obvious of the coupling effect between the two beams and the central rigid body is. The present investigation results are helpful for the dynamic analysis and design of spacecraft structures composed of flexible solar wings and a central rigid body.

A robot screwing skill learning framework based on teaching–learning is proposed to improve the generalization ability of robots for different scenarios and objects, combined with the experience of a human operation. This framework includes task-based teaching, learning, and summarization. We teach a robot to twist and gather the operation’s trajectories, define the obstacles with potential functions, and counter the twisting of the robot using a skill-learning-based dynamic movement primitive (DMP) and Gaussian mixture model–Gaussian mixture regression (GMM-GMR). The hole-finding and screwing stages of the process are modeled. In order to verify the effectiveness of the robot tightening skill learning model and its adaptability to different tightening scenarios, obstacle avoidance trends and tightening experiments were conducted. Obstacle avoidance and tightening experiments were conducted on the robot tightening platform for bolts, plastic bottle caps, and faucets. The robot successfully avoided obstacles and completed the twisting task, verifying the effectiveness of the robot tightening skill learning model and its adaptability to different tightening scenarios.

The objective of this experiment was to investigate the effects of 5,6-dimethylbenzimidazole (5,6-DMB) and cobalt (Co) on the ruminal vitamin B12 synthesis and fermentation parameters of sheep under high concentrate conditions. Twenty-four Kazakh rams (body weight = 39.23 ± 2.61 kg and 8 months old) fitted with permanent ruminal fistulas were randomly divided into four groups with six rams in each group. The control (CON) group was fed a basal ration with a concentrate-to-roughage ratio of 70:30, and the experimental groups (T60, T75 and T90) were fed a basal diet with 60 mg 5,6-DMB+ 0.25 mg Co, 75 mg 5,6-DMB+ 0.5 mg Co and 90 mg 5,6-DMB+ 0.75 mg Co supplied to each kilogram of basal diet, respectively. The experiment lasted for 26 days, with the first 14 days being an adaptation period to allow the sheep to adapt to the diet type and environment, and the second 12 days being a sample period. On 0, 7 and 12 d of the sample period, all sheep were weighed before the morning feed. Rumen fluid samples were collected from all sheep on the last 4 days of the sample period. The results showed that the ruminal vitamin B12 content was higher in trial groups than that of the CON group at 3 h after feeding (p < 0.05). Rumen pH was higher in trial groups than in the CON group at 1, 3 and 5 h after feeding (p < 0.05). The concentration of ruminal ammonia-N was significantly increased in trial groups when compared to the CON group (p < 0.05) at 1 and 3 h after feeding. At 1 and 3 h after feeding, the concentration of propionate in trial groups was higher than that in the CON group (p < 0.05). The rumen microbial protein content reached the highest value at 3 h after feeding, and all trial groups were higher than the CON group (p < 0.05). Thus, the supplementation of 5,6-DMB and Co increased vitamin B12, propionate, ammonia-N and microbial protein contents and pH in the rumen of sheep, and the best results were obtained by the amounts of 75 mg/kg 5,6-DMB and 0.5 mg/kg Co, respectively.

This paper analyzes the typical technical problems arising from dumping and tamping collision interferences in the working faces of conventional mechanized solid backfilling mining (SBM). Additionally, the technical and consecutive characteristics of the solid intelligent backfilling (SIB) method, the execution device, and the corresponding process categories of the SIB process are analyzed. A design for an SIB process flow is presented. Critical algorithms, including automatic recognition and optimization planning based on the cost function and laying the algorithm foundation, are proposed to develop a backfilling process control system. A joint simulation test system is built on a MATLAB/Simulink simulation toolkit (MSST) to simulate and test the optimized algorithms. The results show that the optimized algorithm can realize the automatic optimization planning and automatic interference-recognition adjustment of the backfilling process under actual engineering conditions. In conclusion, this paper analyzes typical technical problems in the conventional backfilling process, designs the SIB process flow, and develops key algorithms to achieve the automatic control of the backfilling process.

The lifting operation of offshore pipelines is an important step in ocean pipeline engineering. An effective analytical method is developed for investigating the mechanical properties of the pipeline based on mechanical, physical, and geometric relationships. By using the shooting and the secant methods to transform the boundary value problem into an initial value one and then solving them with the Runge–Kutta method, the deformation and mechanical properties of the pipeline are calculated. Furthermore, based on the Det Norske Veritas (DNV) offshore standard, the mechanical properties of the pipeline are checked. The finite element method (FEM) by Orcaflex is employed to verify the accuracy of the analytical model. The effects of some factors such as the current velocity and lifting point position on the mechanical properties of the pipeline are analyzed based on the analytical model. The results indicate that the change in current velocity during the lifting process has a minimal effect on the pipeline, but the change in lifting point position significantly affects the deformation and mechanical properties of the pipeline.

To develop an effective suction slot arrangement, computational fluid dynamics simulation software and a high subsonic compressor cascade were used to simulate different suction slots. Based on the effects of various suction slots on the cascade performance under various operating conditions, a novel segmented suction slot structure Seg3 was proposed. The results of the study revealed that in the vicinity of the operating conditions (incidence≤4°), a full-blade height suction slot should be installed at least 5% of the chord length downstream of the corner separation point to effectively remove the separation. For small and medium incidences, the best performance was observed for suction slot SS5, which was located at 60% of the chord length downstream of the leading edge. Analyzing the effects of SS5 and Seg3 on the cascade performance revealed that when the incidence was less than 4°, the reductions in the total pressure loss coefficients for ζsuc of SS5 and Seg3 both exceeded 8.2%. When the incidence was 4° or greater, the ζsuc increased slightly for SS5, whereas it decreased for Seg3, and the ζsuc was reduced. For a 3° incidence, for example, Seg3 reduced the ζsuc and passage blockage by 12.74% and 8.41%, respectively, and increased the static pressure rise coefficient by 18.55% from the baseline values. Thus, the segmented suction slot proposed in this paper outperformed conventional full-blade height suction slots.

Abstract To reduce the inaccuracy of using the monitoring data outside the pit to evaluate the unorganized emission dust source of open pit mine, the circulating accumulation emission model is established. Based on the model, the monitoring data in the pit can be converted into the dust emission from the pit. The main conclusions include: (1) the circulating accumulation emission model is suitable for the dust diffusion process in open pit mine. The ratio of diffusion $$\mu$$ μ and the ratio of surplus $$\varepsilon$$ ε were used to simulate the dust diffusion process in open pit mine, containing emission, retention and diffusion. (2) The initial value of the dust in the pit before the team operation has little influence on the final stable value. (3) When the external dust enters the pit, it will accumulate under the action of eddy current. The dust background value in the pit is different from that outside the pit. (4) The dust emission from the pit can be calculated from the monitoring data in the pit based on the circulating accumulation emission model. The model can deal with environmental changes such as the wind direction and speed, without arranging a lot of external monitoring equipment like the traditional external monitoring methods.

Abstract Flutter is a self‐excited vibration under the interaction of the inertial force, aerodynamic force, and elastic force of the structure. After the flutter occurs, the aircraft structures will exhibit limit cycle oscillation, which will cause catastrophic accidents or fatigue damage to the structures. Therefore, it is of great theoretical and practical significance to study the aeroelastic characteristics and flutter control for improving the aeroelastic stability of aircraft structures. This paper reviews the recent advances in aeroelastic analysis and flutter control of wings and panel structures. The mechanism of aeroelastic flutter of wings and panels is presented. The research methods of aeroelastic flutter for different structures developed in recent years are briefly summarized. Various control strategies including the linear and nonlinear control algorithms as well as the active flutter control results of wings and panels are presented. Finally, the paper ends with conclusions, which highlight challenges of the development in aeroelastic analysis and flutter control, and provide a brief outlook on the future investigations. This study aims to present a comprehensive understanding of aeroelastic analysis and flutter control. It can also provide guidance on the design of new wings and panel structures for improving their aeroelastic stability.

BackgroundOlder adults are more susceptible to severe health outcomes for coronavirus disease 2019 (COVID-19). Universal vaccination has become a trend, but there are still doubts and research gaps regarding the COVID-19 vaccination in the elderly. This study aimed to investigate the efficacy, immunogenicity, and safety of COVID-19 vaccines in older people aged ≥ 55 years and their influencing factors.MethodsRandomized controlled trials from inception to April 9, 2022, were systematically searched in PubMed, EMBASE, the Cochrane Library, and Web of Science. We estimated summary relative risk (RR), rates, or standardized mean difference (SMD) with 95% confidence interval (CI) using random-effects meta-analysis. This study was registered with PROSPERO (CRD42022314456).ResultsOf the 32 eligible studies, 9, 21, and 25 were analyzed for efficacy, immunogenicity, and safety, respectively. In older adults, vaccination was efficacious against COVID-19 (79.49%, 95% CI: 60.55−89.34), with excellent seroconversion rate (92.64%, 95% CI: 86.77−96.91) and geometric mean titer (GMT) (SMD 3.56, 95% CI: 2.80−4.31) of neutralizing antibodies, and provided a significant protection rate against severe disease (87.01%, 50.80−96.57). Subgroup and meta-regression analyses consistently found vaccine types and the number of doses to be primary influencing factors for efficacy and immunogenicity. Specifically, mRNA vaccines showed the best efficacy (90.72%, 95% CI: 86.82−93.46), consistent with its highest seroconversion rate (98.52%, 95% CI: 93.45−99.98) and GMT (SMD 6.20, 95% CI: 2.02−10.39). Compared to the control groups, vaccination significantly increased the incidence of total adverse events (AEs) (RR 1.59, 95% CI: 1.38−1.83), including most local and systemic AEs, such as pain, fever, chill, etc. For inactivated and DNA vaccines, the incidence of any AEs was similar between vaccination and control groups (p > 0.1), while mRNA vaccines had the highest risk of most AEs (RR range from 1.74 to 7.22).ConclusionCOVID-19 vaccines showed acceptable efficacy, immunogenicity and safety in older people, especially providing a high protection rate against severe disease. The mRNA vaccine was the most efficacious, but it is worth surveillance for some AEs it caused. Increased booster coverage in older adults is warranted, and additional studies are urgently required for longer follow-up periods and variant strains.

This study aims to obtain anaerobic fungi from the rumen and fecal samples and investigates their potential for lignocellulosic bioconversion. Multiple anaerobic strains were isolated from rumen contents (CR1–CR21) and fecal samples (CF1–CF10) of Bactrian camel using the Hungate roll tube technique. After screening for fiber degradability, strains from rumen contents (Oontomyces sp. CR2) and feces (Piromyces sp. CF9) were compared with Pecoramyces sp. F1 (earlier isolated from goat rumen, having high CAZymes of GHs) for various fermentation and digestion parameters. The cultures were fermented with different substrates (reed, alfalfa stalk, Broussonetia papyrifera leaves, and Melilotus officinalis) at 39°C for 96 h. The Oontomyces sp. CR2 had the highest total gas and hydrogen production from most substrates in the in vitro rumen fermentation system and also had the highest digestion of dry matter, neutral detergent fiber, acid detergent fiber, and cellulose present in most substrates used. The isolated strains provided higher amounts of metabolites such as lactate, formate, acetate, and ethanol in the in vitro rumen fermentation system for use in various industrial applications. The results illustrated that anaerobic fungi isolated from Bactrian camel rumen contents (Oontomyces sp. CR2) have the highest lignocellulosic bioconversion potential, suggesting that the Bactrian camel rumen could be a good source for the isolation of anaerobic fungi for industrial applications.

Abstract Background Prunus pedunculata Pall, the deciduous shrub of Amygdalus subgenus in Rosaceae, is a new kind of desert oil-bearing tree. It has a long story of being planted in the West and North of China for sand fixation and desert control. In addition, the seeds of P. pedunculata are rich of oil, especially the monounsaturated fatty acid and polyunsaturated fatty acid. However, little is known about the molecular mechanisms of oil accumulation during the seed development of P. pedunculata. Results The seeds of P. pedunculata from three independent plants at 10, 18, 24, 31, 39, 45, 59 and 73 days after flowering (DAF) were obtained and the oil compositions were evaluated. It showed that oleic acid was the dominant type of oil content in the mature seeds (from 32.724% at 10DAF to 72.06% at 73DAF). Next, transcriptome sequencing for the developing seeds produced 988.795 million high quality reads and TRINITY assembled 326,271 genes for the first transcriptome for P. pedunculata. After the assembled transcriptome was evaluated by BUSCO with 85.9% completeness, we identified 195,342, 109,850 and 121,897 P. pedunculata genes aligned to NR, GO and KEGG pathway databases, respectively. Then, we predicted 23,229 likely proteins from the assembled transcriptome and identified 1917 signal peptides and 5512 transmembrane related proteins. In the developing seeds we detected 91,362 genes (average FPKM > 5) and correlation analysis indicated three possible development stages – early (10 ~ 24DAF), middle (31 ~ 45DAF) and late (59 ~ 73DAF). We next analyzed the differentially expressed genes (DEGs) in the developing seeds. Interestingly, compared to 10DAF the number of DEGs was increased from 4406 in 18DAF to 27,623 in 73DAF. Based on the gene annotation, we identified 753, 33, 8 and 645 DEGs related to the fatty acid biosynthesis, lipid biosynthesis, oil body and transcription factors. Notably, GPAT, DGD1, LACS2, UBC and RINO were highly expressed at the early development stage, ω6-FAD, SAD, ACP, ACCA and AHG1 were highly expressed at the middle development stage, and LACS6, DGD1, ACAT1, AGPAT, WSD1, EGY2 and oleosin genes were highly expressed at the late development stage. Conclusions This is the first time to study the developing seed transcriptome of P. pedunculata and our findings will provide a valuable resource for future studies. More importantly, it will improve our understanding of molecular mechanisms of oil accumulation in P. pedunculata.

The species Brassica rapa includes enormous leafy vegetables with extreme leaf morphological diversity. Leaf traits such as size, shape, weight, and ratio of the leaf blade to the petiole contribute to yield, appearance, and desirability to consumers. These leaf-related traits are controlled by quantitative trait loci (QTLs). The construction of high-density bin maps using low-coverage sequencing is a powerful method for QTL fine-mapping and gene identification. In this study, we performed whole-genome re-sequencing of Wutacai ‘Zhongbaye’ and Chinese cabbage ‘HN53’ and 150 F2 individuals to construct a high-density bin map for QTL mapping of 11 leaf-related traits. The parental lines and F2 population were re-sequenced at 10x and 1x coverage, respectively. A map containing 565 bin markers was constructed based on parental single-nucleotide polymorphisms and a modified sliding window approach. The total map length was 944.6 cM and the average distance of the bins was 1.65 cM. In total, 60 significant QTLs controlling 11 leaf-related traits were detected. We further identified candidate genes responsible for these complex leaf-related traits. These findings suggest that this cost-effective bin-mapping approach is capable of rapid identification of QTLs and candidate genes, and will thus facilitate the dissection of the underlying molecular basis of leaf morphological variations and accelerate the improvement of B. rapa vegetable breeding.

Abstract To study the heights of the caved zone and water-conducting fracture zone in backfill mining, the failure mechanism of strata during backfill mining was analyzed, and a method for determining the heights of the two zones was proposed based on key strata theory. The movement and failure regularity of the strata above the backfilling panel were revealed through numerical simulation. Considering the geologic conditions of the CT101 backfilling panel, the height of the fracture zone was determined using the proposed method along with empirical calculation, numerical simulation, and borehole detection. The results of the new calculation method were similar to in situ measurements. The traditional empirical formula, which is based on the equivalent mining height model, resulted in large errors during calculation. The findings indicate the reliability of the new method and demonstrate its significance for creating reference data for related studies.

Automatic assembly of elastic components is difficult because of the potential deformation of parts during the assembly process. Consequently, robots cannot adapt their manipulation to dynamic changes. Designing systems that learn assembly skills can help in alleviating the uncertain factor for industrial-grade assembly robots. This study proposes a skill acquisition method based on multi-modal information description to realize the assembly of systems with elastic components. This multi-modal information includes two-dimensional images, poses, forces/torques, and robot joint parameters. In this method, robots acquire searching, location determination, and pose adjustment skills using these multi-modal information parameters. As a result, robots can reach the assembly target by analyzing two-dimensional images with no position constraint. While acquiring pose adjustment skills, the reward function with depth and assembly steps is used to improve the learning efficiency. The deep deterministic policy gradient (DDPG) algorithm is applied for acquiring skills. Experiments using a KUKA iiwa robot demonstrated the effectiveness and conciseness of our method. Our results indicate that the robot acquired searching, location determination, and pose adjustment skills that allowed it to successfully complete elastic assembly.

Aspergillus niger is one of the major pathogenic fungi causing postharvest grape decay. The development of antifungal agents is beneficial to reduce the loss of grapes during storage. The aim of this study was to investigate the antifungal mechanism of cyclosporin A (CsA). It was indicated that the rot development on grapes caused by A. niger was almost completely inhibited with CsA in vivo at a concentration of 200 mg/L. The transcriptomic analysis revealed that the expression levels of genes involved in rRNA processing and ribosome biogenesis were down-regulated, whereas those related to β-glucosidases and chitinases were up-regulated. The results implied that CsA may disturb rRNA and ribosome formation to obstruct protein synthesis, accelerate chitin and glucan degradation to destruct cell walls, and ultimately reduce postharvest decay caused by A. niger in grapes. This study evaluated the potential of CsA as a grape preservative and provided new insights into the mechanisms underlying the molecular response in A. niger with the treatment of CsA.

In this study, elastic metamaterial sandwich plates with axially deformed Timoshenko beam cores, considering both the out-of-plane and in-plane deformations of the face plates, are designed and the vibration band-gap properties are explored. The beam cores act as local resonators that can bear axial force, bending moment and shearing force. The finite element method (FEM) and the spectral element method (SEM) are combined to create the finite/spectral element hybrid method (FE-SEHM) for establishing the dynamic model and calculating the frequency response functions (FRFs) of the elastic metamaterial sandwich plate with axially deformed beam cores. It is observed that the metamaterial sandwich plate possesses both the axial and transverse vibration band-gaps of the beams, and the two kinds of band-gaps are independent. Compared with the metamaterial sandwich plates with rod cores, those with axially deformed beam cores have more extensive application ranges for vibration reduction.

Robot automatic assembly of weak stiffness parts is difficult due to potential deformation during assembly. The robot manipulation cannot adapt to the dynamic contact changes during the assembly process. A robot assembly skill learning system is designed by combining the compliance control and deep reinforcement, which could acquire a better robot assembly strategy. In this paper, a robot assembly strategy learning method based on variable impedance control is proposed to solve the robot assembly contact tasks. During the assembly process, the quality evaluation is designed based on fuzzy logic, and the impedance parameters in the assembly process are studied with a deep deterministic policy gradient. Finally, the effectiveness of the method is verified using the KUKA iiwa robot in the weak stiffness peg-in-hole assembly. Experimental results show that the robot obtains the robot assembly strategy with variable compliant in the process of weak stiffness peg-in-hole assembly. Compared with the previous methods, the assembly success rate of the proposed method reaches 100%.

Methicillin-resistant Staphylococcus aureus (MRSA) is highly concerning as a principal infection pathogen. The investigation of higher effective natural anti-MRSA agents from marine Streptomyces parvulus has led to the isolation of actinomycin D, that showed potential anti-MRSA activity with MIC and MBC values of 1 and 8 μg/mL, respectively. Proteomics-metabolomics analysis further demonstrated a total of 261 differential proteins and 144 differential metabolites induced by actinomycin D in MRSA, and the co-mapped correlation network of omics, indicated that actinomycin D induced the metabolism pathway of producing the antibiotic sensitivity in MRSA. Furthermore, the mRNA expression levels of the genes acnA, ebpS, clfA, icd, and gpmA related to the key differential proteins were down-regulated measured by qRT-PCR. Molecular docking predicted that actinomycin D was bound to the targets of the two key differential proteins AcnA and Icd by hydrogen bonds and interacted with multiple amino acid residues of the proteins. Thus, these findings will provide a basic understanding to further investigation of actinomycin D as a potential anti-MRSA agent.

Staphylococcus aureus (S. aureus) is a common pathogen that causes various serious diseases, including chronic infections. Discovering new antibacterial agents is an important aspect of the pharmaceutical field because of the lack of effective antibacterial drugs. In our research, we found that one anti-S. aureus substance is actinomycin D, originating from Streptomyces parvulus (S. parvulus); then, we further focused on the anti-S. aureus ability and the omics profile of S. aureus in response to actinomycin D. The results revealed that actinomycin D had a significant inhibitory activity on S. aureus with a minimum inhibitory concentration (MIC) of 2 μg/mL and a minimum bactericidal concentration (MBC) of 64 μg/mL. Bacterial reactive oxygen species (ROS) increased 3.5-fold upon treatment with actinomycin D, as was measured with the oxidation-sensitive fluorescent probe DCFH-DA, and H2O2 increased 3.5 times with treatment by actinomycin D. Proteomics and metabolomics, respectively, identified differentially expressed proteins in control and treatment groups, and the co-mapped correlation network of proteomics and metabolomics annotated five major pathways that were potentially related to disrupting the energy metabolism and oxidative stress of S. aureus. All findings contributed to providing new insight into the mechanisms of the anti-S. aureus effects of actinomycin D originating from S. parvulus.

The purpose of this study is to investigate the potential effects of 5-hydroxytryptophan (5-HTP) duodenal perfusion on melatonin (MT) synthesis in the gastrointestinal (GI) tract of sheep. 5-hydroxytryptophan is a precursor in the melatonin synthetic pathway. The results showed that this method significantly increased melatonin production in the mucosa of all segments in GI tract including duodenum, jejunum, ileum, cecum and colon. The highest melatonin level was identified in the colon and this indicates that the microbiota located in the colon may also participate in the melatonin production. In addition, portion of the melatonin generated by the GI tract can pass the liver metabolism and enters the circulation via portal vein. The current study provides further evidence to support that GI tract is the major site for melatonin synthesis and the GI melatonin also contributes to the circulatory melatonin level since plasma melatonin concentrations in 5-HTP treated groups were significantly higher than those in the control group. In conclusion, the results show that 10–50 mg of 5-HTP flowing into the duodenum within 6 h effectively improve the production of melatonin in the GI tract and melatonin concentration in sheep blood circulation during the day.

Campylobacteriosis is the most common cause of bacterial gastroenteritis worldwide. Consumption of chicken meat is considered the main route for human infection with Campylobacter. This study aimed to determine the critical factors for Campylobacter cross-contamination in Chinese commercial kitchens during chicken handling. Five commercial kitchens were visited to detect Campylobacter occurrence from 2019 to 2020. Chicken samples (n = 363) and cotton balls from the kitchen surfaces (n = 479) were collected, and total bacterial counts and Campylobacter spp. were detected. Genotypic characterization of 57 Campylobacter jejuni isolates was performed by multilocus sequence typing (MLST). In total, 77.41% of chicken carcass samples and 37.37% of kitchen surfaces showed Campylobacter spp. contamination. Before chicken preparation, Campylobacter spp. were already present in the kitchen environment; however, chicken handling significantly increased Campylobacter spp. prevalence (p < 0.05). After cleaning, boards, hands, and knives still showed high bacterial loads including Campylobacter spp., which related to poor sanitary conditions and ineffective handling practices. Poor sanitation conditions on kitchen surfaces offer greater opportunities for Campylobacter transmission. Molecular typing by MLST revealed that Campylobacter cross-contamination occurred during chicken preparation. The most prevalent sequence types, ST693 and ST45, showed strong biofilm formation ability. Consequently, sanitary condition of surfaces and biofilm formation ability of isolates were the critical points contributing to spread of Campylobacter in kitchen environment. These results provide insight into potential targeted control strategies along the farm-to-plate chain and highlight the necessity for improvements in sanitary conditions. The implementation of more effective cleaning measures should be considered to decrease the campylobacteriosis risk.

Campylobacter jejuni is an important foodborne pathogen causing campylobacteriosis. It can infect humans through the consumption of contaminated chicken products or via the direct handling of animals. Diallyl trisulfide (DATS) is a trisulfide compound from garlic extracts that has a potential antimicrobial effect on foodborne pathogens. This study investigated the antimicrobial activity of DATS on C. jejuni by evaluating the minimal inhibitory concentrations (MICs) of C. jejuni 81-168, and fourteen C. jejuni isolates from chicken carcasses. Thirteen of 14 C. jejuni isolates and 81-176 had MICs ≤ 32 μg/mL, while one isolate had MIC of 64 μg/mL. Scanning electron microscopy (SEM) analysis showed the disruption and shrink of C. jejuni bacterial cell membrane after the DATS treatment. A time-killing analysis further showed that DATS had a dose-dependent in vitro antimicrobial effect on C. jejuni during the 24 h treatment period. In addition, DATS also showed an antimicrobial effect in chicken through the decrease of C. jejuni colony count by 1.5 log CFU/g (cloacal sample) during the seven-day DATS treatment period. The transcriptional analysis of C. jejuni with 16 μg/mL (0.5× MIC) showed 210 differentially expression genes (DEGs), which were mainly related to the metabolism, bacterial membrane transporter system and the secretion system. Fourteen ABC transporter-related genes responsible for bacterial cell homeostasis and oxidative stress were downregulated, indicating that DATS could decrease the bacterial ability to against environmental stress. We further constructed five ABC transporter deletion mutants according to the RNA-seq analysis, and all five mutants proved less tolerant to the DATS treatment compared to the wild type by MIC test. This study elucidated the antimicrobial activity of DATS on C. jejuni and suggested that DATS could be used as a potential antimicrobial compound in the feed and food industry.

At present, the production lines of mobile phones are mainly manual and semi-automatic. Robots are the most important tools used to improve the intelligence level of industry production. The design of an intelligent robotic assembly system is presented in this paper, which takes the assembly of screen components and shell components as examples. There are major factors restricting the application of robots, such as the calibration of diversified objects, the moving workpiece with incomplete information, and diverse assembly types. A method was proposed to solve these technological difficulties. The multi-module calibration method is used to transform the pose relationship between the robot, the conveyor belt, and the two cameras in the robot assembly system. Aiming at a workpiece moving with incomplete information, the minimum matrix method is proposed to detect the position. Then dynamic fetching is realized based on pose estimation of the moving workpiece. At last, the template matching method is used to identify the assembly area of the workpiece type. The proposed method was verified on a real platform with a LINKHOU LR4-R5 60 robot. Results showed that the assembly success rate was above 98%, and the intelligent assembly system of the robot can realize the assembly of mobile phone screens and back shells without any staff.