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The annual trading declaration of the electricity market for Kaidu River Cascade Hydropower Station depends on an accurate assessment of their power generation capacity. In order to fully tap the power generation dispatching potential of the hydropower station, rationally declare the annual power generation plan, and guarantee the economic benefits of the hydropower station, it is imperative to carry out research on the power generation dispatching potential of Kaidu River Cascade Hydropower Station. This study focused on Kaidu River Cascade Hydropower Station, aiming to minimize water shortage rates and maximize power generation. A multi-objective optimization dispatching model was created, and it was solved by using an improved NSGA-II algorithm. The model results were compared with simulated dispatching to tap the power generation of optimization dispatching. The results show that: ① Compared with simulation dispatching, optimization dispatching improves output reliability and increases power generation. Under simulation dispatching, the annual average power generation of Kaidu River Cascade Hydropower Station is 1.678 billion kW·h. Optimization dispatching obtains an additional 133 million kW·h (8% increase) in the annual average power generation; ② in different typical years, optimization dispatching has different effects on power generation dispatching potential exploitation of Kaidu River Cascade Hydropower Station, especially in extreme dry years, where the increase is 1.95 times that of normal years and 6.68 times that of extreme wet years. These results provide a decision-making basis for annual trading plan declarations of cascade hydropower stations and ensure the economic benefits of cascade hydropower stations.

[Significance]The rapid development of artificial intelligence and automation has greatly expanded the scope of agricultural automation, with applications such as precision farming using unmanned machinery, robotic grazing in outdoor environments, and automated harvesting by orchard-picking robots. Collaborative operations among multiple agricultural robots enhance production efficiency and reduce labor costs, driving the development of smart agriculture. Multi-robot simultaneous localization and mapping (SLAM) plays a pivotal role by ensuring accurate mapping and localization, which are essential for the effective management of unmanned farms. Compared to single-robot SLAM, multi-robot systems offer several advantages, including higher localization accuracy, larger sensing ranges, faster response times, and improved real-time performance. These capabilities are particularly valuable for completing complex tasks efficiently. However, deploying multi-robot SLAM in agricultural settings presents significant challenges. Dynamic environmental factors, such as crop growth, changing weather patterns, and livestock movement, increase system uncertainty. Additionally, agricultural terrains vary from open fields to irregular greenhouses, requiring robots to adjust their localization and path-planning strategies based on environmental conditions. Communication constraints, such as unstable signals or limited transmission range, further complicate coordination between robots. These combined challenges make it difficult to implement multi-robot SLAM effectively in agricultural environments. To unlock the full potential of multi-robot SLAM in agriculture, it is essential to develop optimized solutions that address the specific technical demands of these scenarios.[Progress]Existing review studies on multi-robot SLAM mainly focus on a general technological perspective, summarizing trends in the development of multi-robot SLAM, the advantages and limitations of algorithms, universally applicable conditions, and core issues of key technologies. However, there is a lack of analysis specifically addressing multi-robot SLAM under the characteristics of complex agricultural scenarios. This study focuses on the main features and applications of multi-robot SLAM in complex agricultural scenarios. The study analyzes the advantages and limitations of multi-robot SLAM, as well as its applicability and application scenarios in agriculture, focusing on four key components: multi-sensor data fusion, collaborative localization, collaborative map building, and loopback detection. From the perspective of collaborative operations in multi-robot SLAM, the study outlines the classification of SLAM frameworks, including three main collaborative types: centralized, distributed, and hybrid. Based on this, the study summarizes the advantages and limitations of mainstream multi-robot SLAM frameworks, along with typical scenarios in robotic agricultural operations where they are applicable. Additionally, it discusses key issues faced by multi-robot SLAM in complex agricultural scenarios, such as low accuracy in mapping and localization during multi-sensor fusion, restricted communication environments during multi-robot collaborative operations, and low accuracy in relative pose estimation between robots.[Conclusions and Prospects]To enhance the applicability and efficiency of multi-robot SLAM in complex agricultural scenarios, future research needs to focus on solving these critical technological issues. Firstly, the development of enhanced data fusion algorithms will facilitate improved integration of sensor information, leading to greater accuracy and robustness of the system. Secondly, the combination of deep learning and reinforcement learning techniques is expected to empower robots to better interpret environmental patterns, adapt to dynamic changes, and make more effective real-time decisions. Thirdly, large language models will enhance human-robot interaction by enabling natural language commands, improving collaborative operations. Finally, the integration of digital twin technology will support more intelligent path planning and decision-making processes, especially in unmanned farms and livestock management systems. The convergence of digital twin technology with SLAM is projected to yield innovative solutions for intelligent perception and is likely to play a transformative role in the realm of agricultural automation. This synergy is anticipated to revolutionize the approach to agricultural tasks, enhancing their efficiency and reducing the reliance on labor.

In order to optimize engineering layout, alleviate the contradiction between water supply and demand, and improve the comprehensive utilization efficiency of water resources in the basin, this study took the sources of the Tarim River including the Aksu River, Hotan River, and Yeerqiang River and its main streams as the research objects. In response to problems such as the large evaporation and seepage losses of plain reservoirs within the river basin and the prominent contradiction between supply and demand of water resources, a joint allocation model of reservoir groups was established and solved. The research results show that a scheme for replacing plain reservoirs in the main streams with mountainous reservoirs has been developed and optimized. By replacing the plain reservoir groups in the main streams, the total water shortage and water loss in the basin can be significantly reduced, and the contradiction between water supply and demand in the basin can be eased. On the basis of meeting the demand for industrial and domestic water, properly reducing the water discharge in the source area can greatly alleviate the water contradiction between the source area and the main stream area and improve the irrigation water supply in the basin. Under the objective of optimized planning, a water resources allocation scheme is made. To be specific, under the condition of average water supply for many years, the water supply for agricultural irrigation and ecological water supply outside the river are 13.502 billion m3 and 1.404 billion m3, respectively. The research results provide technical support for guiding the abandonment of plain reservoirs and have scientific guiding significance and demonstration value for ecological protection and sustainable utilization of water resources in similar basins in arid areas.

The annual trading declaration of the electricity market for Kaidu River Cascade Hydropower Station depends on an accurate assessment of their power generation capacity. In order to fully tap the power generation dispatching potential of the hydropower station, rationally declare the annual power generation plan, and guarantee the economic benefits of the hydropower station, it is imperative to carry out research on the power generation dispatching potential of Kaidu River Cascade Hydropower Station. This study focused on Kaidu River Cascade Hydropower Station, aiming to minimize water shortage rates and maximize power generation. A multi-objective optimization dispatching model was created, and it was solved by using an improved NSGA-II algorithm. The model results were compared with simulated dispatching to tap the power generation of optimization dispatching. The results show that: ① Compared with simulation dispatching, optimization dispatching improves output reliability and increases power generation. Under simulation dispatching, the annual average power generation of Kaidu River Cascade Hydropower Station is 1.678 billion kW·h. Optimization dispatching obtains an additional 133 million kW·h (8% increase) in the annual average power generation; ② in different typical years, optimization dispatching has different effects on power generation dispatching potential exploitation of Kaidu River Cascade Hydropower Station, especially in extreme dry years, where the increase is 1.95 times that of normal years and 6.68 times that of extreme wet years. These results provide a decision-making basis for annual trading plan declarations of cascade hydropower stations and ensure the economic benefits of cascade hydropower stations.

Millet was treated at 600 MPa for 15 min and 30 min, respectively (millet: water=1∶1 or 1∶2 (w/w). The effects of different treatment conditions on physicochemical and functional properties of millet flour were investigated to provide a theoretical basis for optimizing the quality characteristics of millet powder. The results showed that high hydrostatic pressure (HHP) treatment affected the morphology, particle size, and crystal characteristics of the four different millet powders. The morphology of starch particles in the whole flour changed from a scattered irregular sphere to complex and bonded to block structure with other substances, and the average particle size decreased significantly. The overall particle size shrank, and the crystal structure changed from natural A type to B type. The effect on the microstructure was particularly significant when the ratio of millet to water was 1∶2. The dynamic rheological tests showed that Gʹ and tanδ of millet paste after HHP treatment were higher than those of original powder, and Gʺ was lower than that of original powder. The results showed that HHP treatment could improve the elasticity and viscosity of millet starch, and this technology could be used as an effective physical modification method to improve the physical properties of millet powder.

The saltwater intrusion in the Pearl River Delta has caused huge economic losses andsocial impacts to the surrounding areas. It is extremely urgent to reduce the adverse effects ofthe saltwater intrusion. Taking the eight key reservoirs in the Xijiang River Basin as theresearch object, this paper formulates the real-time dispatching simulation schemes of singlereservoir, two reservoirs and eight reservoirs in dry season respectively, and aiming at the low-water conditions of 95% and 99% incoming water frequency, establishes and applies the real-timedispatching simulation model of key reservoirs in the Xijiang River Basin to meet the saltwaterresistance and freshwater supplement demand of Wuzhou section at the downstream of Xijiang RiverBasin. The results show that: ① In the case of single-reservoir dispatching, and in the 95%incoming water scenario, Tianyi, Guangzhao, Longtan and Yantan reservoirs can meet the saltwaterresistance demand of the Wuzhou section. In the 99% incoming water scenario, only Tianyi andLongtan reservoirs can meet the saltwater resistance demand; ② The joint dispatching of tworeservoirs and seven reservoirs under different incoming water can meet the target of saltwaterresistance and freshwater supplement, and the water level of Longtan drops at the most flattrend; ③ In the process of saltwater resistance and freshwater supplement, the priority of allreservoirs is: Longtan, Tianyi, Yantan, Guangzhao, Xijin, Baise. The research results haveimportant theoretical significance for reducing the impact of salt tides in the Pearl River Delta,and provide an important reference for the subsequent real-time optimal dispatching of the keyreservoirs in the Xijiang River Basin.

Preparation of calcium-modified biochar (ca-Bc) using corn stover biochar (Bc) as raw material and calcium chloride (cacl2) as modifier. The changes in morphological composition of biochar before and after modification were compared, and the effect of ca-Bc on the phosphate adsorption and the role of different pH for it were explored. Meanwhile, investigated the effect of ca-Bc on various forms of phosphorus in the substrate, to clarify the effect of ca-Bc on the control of phosphorus in the water body and the substrate. The results showed: (1) compared with Bc, ca-Bc had a denser pore structure, larger specific surface area, and more adsorption sites and oxygen-containing functional groups. Under neutral conditions, ca-Bc prepared at a cad2 concentration of 1.0molL-1 had the best adsorption effect on phosphate, at which time the removal rate of phosphate could reach 88.3%, which was nearly 3 times higher removal rate than Bc. (2) The adsorption process of ca-Bc on phosphate conformed to the quasi-primary, quasi-secondary kinetic model and Langmuir isothermal adsorption model, which was mainly determined by single-molecule adsorption and influenced by both diffusion and chemisorption, and the theoretical maximum adsorption amount reaches 15.6mol L-1. (3) Addition of ca-Bc to the substrate, the proportion of exchange phosphorus (Ex-P), organic phosphorus (Org-P), and calcium-bound phosphorus (Ca-P) decreased from 0.5% to 0.3%, 22.6% to 19.4%, and 39.1% to 41.5%. Therefore, the addition of Ca-BC can promote the morphological transformation of substrate phosphorus, resulting in a decrease in the proportion of potentially reactive phosphorus and an increase in the proportion of stable state phosphorus, reducing the risk of substrate phosphorus release. [ABSTRACT FROM AUTHOR]

Soil moisture and nitrogen nutrient are the two principal factors affecting rice production. Alternating dry and wet irrigation (AWD) coupled with nitrogen application plays important roles in root growth and yield formation in rice. However, its effect on grain filling physiology and their relationship with root physiology is not clearly understood. To explore the effects of alternating dry and wet irrigation and nitrogen application coupling on grain filling, changes of key enzyme activities involved in sucrose-to starch conversion and hormone contents, and root physiology of rice, the super rice variety Nanjing 9108 was cultivated as the material in the field. The field experiments were conducted with two irrigation regimes [conventional irrigation (CI) and AWD] and five nitrogen application rates [no nitrogen fertilizer (0N), 90 kg hm-2 (90N), 180 kg hm-2 (180N), 270 kg hm-2 (270N), and 360 kg hm-2 (360N) nitrogen fertilizer]. The results showed that there was a significant interaction effect between irrigation method and nitrogen application rate. Alternating dry and wet irrigation increased the maximum grain filling rate and average grain filling rate of Nanjing 9108, and increased the activities of the sucrose synthase enzymes, adenosine diphosphate glucose pyrophosphorylation enzymes, starch synthase enzymes, and starch branching enzymes, and the contents of zeatin + zeatin riboside, 3-indoleacetic acid and abscisic acid, increased root oxidation activity, and the content of zeatin + zeatin riboside in roots after heading, promoted the transfer of NSC stored in the stem sheath to the grain in the early growth stage of rice, and the highest yield was obtained after coupling with 270N, which was the best water-nitrogen coupling mode in this experiment. In conclusion, the water-nitrogen coupling effect can be exerted by appropriate regulation of water and fertilizer, which can improve the physiological performance of rice roots and grain-filling physiological activity, and achieve high rice yield. [ABSTRACT FROM AUTHOR]

The experiment was to monitor the degradation effect of anti-nutritional factors during soybean meal fermentation. The β-mannanase producing strain HTGC-10 stored in the laboratory was used as the fermentation strain to degrade mannan. The degradation effect of strain HTGC-10 was detected by thin layer chromatography and real-time electrophoresis. The results showed that strain HTGC-10 could degrade mannan to small mannooligosaccharide. HTGC-10 was used to ferment 10% soybean meal. The results of real-time electrophoresis showed that HTGC-10 could degrade macromolecular proteins in soybean meal well within 0~24 h of fermentation. In 0~24 h of fermentation, HTGC-10 could degrade the antitrophic factors well, and the antitrophic factors of soybean globulin, β -associated soybean globulin and KTI in soybean meal to 11.9%, 18.5% and 2.0% of the original contents, respectively. The continuous fermentation for 24~48 h had little effect on the degradation of antitrophic factors in soybean meal. The study indicates that the fermentation time of soybean meal should be 24 h to make better use of soybean meal resources. [ABSTRACT FROM AUTHOR]

We screened and identified an endophytic bacterium that could efficiently degrade PAHs, which would expand the library of polycyclic aromatic hydrocarbons (PAHs) degrading microorganisms and reduce the pollution risk of crops. Its degradation mechanism and colonization performance were preliminarily examined. The results showed that strain PX1 belonged to Stenotrophomonas maltophilia. The strain had broad spectrum ability to remove PAHs. In PAH mineral salt (MS) media, almost 100% naphthalene was degraded by strain PX1 after 7-d incubation. In a cultivation system solely containing phenanthrene of 50.0 mg ⋅ L-1, pyrene of 20.0 mg ⋅ L-1, fluoranthene of 20.0 mg ⋅ L-1 or benzo[a] pyrene of 10.0 mg ⋅ L-1, the degradation efficiency of phenanthrene, pyrene, fluoranthene and benzo [a] pyrene by strain PX1 reached 72.6%, 50.7%, 31.9%, and 12.9%, respectively. Pyrene was selected as PAHs model to study the degradation characteristics of strain PX1. Enzyme activity tests showed that the activities of phthalate dioxygenase, catechol-1, 2-dioxygenase, and catechol-2, 3-dioxygenase in strain PX1 were induced by pyrene. Some metabolic intermediates such as 4,5-epoxypyrene, 4,5-dihydroxypyrene, gentilic acid/protocatechuic acid, salicylic acid, cis-hexadienedioic acid/2-hydroxymyxofuroic acid semialdehyde, cis-2'-carboxyphenylpyruvic acid, 1-hydroxy-2-naphthoic acid, and salicylaldehyde were detected during the degradation of pyrene by strain PX1. Results of the seed soaking experiment showed that strain PX1 could efficiently colonize in Ipomoea aquatic and Triticum aestivum. After inoculated with strain PX1, the growth of I. aquatic and T. aestivum was significantly increased, and the pyrene concentration in I. aquatic, T. aestivum and MS media was reduced by 29.8%-50.7%, 52.4%-67.1% and 8.0%-15.3%, respectively. Our results suggested that strain PX1 degraded pyrene mainly through 'salicylate pathway' and 'phthalate pathway', and could be colonized into plants and promote plant growth. [ABSTRACT FROM AUTHOR]

To investigate the influence of coaxial airflow on the piezoelectric droplet injection process, a computational fluid dynamics model was established, and the two-dimensional numerical simulation of a piezoelectric spray nozzle with coaxial airflow injection tank was performed. The velocity and pressure field distribution characteristics of the nozzle internal and external fluid area were analyzed based on the calculation results. The result shows that the coaxial airflow meets just below the nozzle and disperses to the left and right sides to form axisymmetric pairs of vortices in the air domain. With the continuous spraying of airflow, the number of vortices increases and continues to strengthen and expand and continue to move downstream to the nozzle. The introduction of coaxial airflow leads to the increase of the amplitude of piezoelectric membrane and decrease of pressure in air domain, while the pressure in vortex region which is located just beneath the nozzle and diffused by the airflow on both sides decreases significantly. With the increase of coaxial airflow velocity, the droplet fracture moment is delayed, the droplet shape tends to change from ellipsoidal to spherical, the droplet extension length increases, and the droplet diameter increases. [ABSTRACT FROM AUTHOR]

In the ancient concrete building, concrete beams with plain steel reinforcement under the load will evolve from flexural failure to shear failure with the increase of service time. The existing bearing capacity analysis model of the concrete beam with plain steel reinforcement couldn't distinguish these two failure modes. By selecting concrete beam reinforced with plain bars as research object, the calculated formula of bonding strength between plain steel bar and concrete was proposed and the effect of relatively small bond strength on the load bearing capacity of concrete beams was analyzed in detail. Based on the strut-tie model and the standard truss model, the bearing capacity of the concrete beams was calculated. The results showed that the average ratio of the test values to the analytical values of the strut-tie model and the standard truss model was 1.460 and 1.309, respectively, and the variance was 0.858 and 0.781, respectively. The variable angle truss calculation model was established which could distinguish the failure mode of the concrete beams with plain steel reinforcement. The suggested model was validated by the experimental data of 32 concrete beams. The average ratio of the test results of the bearing capacity of the concrete beams to the calculated values of the variable angle truss model was 1.034 and the variance was 0.100, which indicated that test results and prediction results were in a good agreement. The modified variable angle truss model could precisely predict the failure mode of the reinforced concrete beam with plain steel bar. Thus, the suggested model could be used to calculate the load bearing capacity and analyze the failure mode of concrete beams reinforced with plain steel bars. [ABSTRACT FROM AUTHOR]

Composite structures have been widely used in the field of aerospace.In order to study the mechanical properties of composites in hygrothermal environments,the pull-through tests of a type of polyimide composite laminates are carried out under three test environments:cold temperature dry(CTD),room temperature dry(RTD)and elevated temperature wet(ETW).The numerical simulation analysis of the RTD test process is carried out.The pull-through strength and failure mode of two typical laminates are obtained by experiment,and the failure load is predicted by simulation analysis.The results show that the type of polyimide composites have excellent thermal stability.The pull-through strength of the composites under CTD condition is 8.1%~9.0% higher than that under RTD condition,and the pull-through strength of the composites under ETW condition is equivalent to that under RTD condition.The pull-through strength of(30/60/10)ply is slightly higher than(40/50/10)ply.

An adaptive watermarking algorithm based on computer generated holography with strong robustness is proposed. Firstly, two original watermarks are converted to holograms using the computer generated holography by the conjugate-symmetric extension. And the holograms are encrypted by the pre-process method. Then, the original image is decomposed into two pyramidal levels by Con-tourlet transform, and the intermediate frequency is transformed into eight directional subbands. Finally, encrypted holograms are embedded into the directional subbands adaptively. Experiments demonstrate that the PSNR of watermarked image is 38. 385 7 dB. The extracted watermarks can be well recognized when JPEG compression quality factor is bigger than 30 and cropping part is less than 30%. The proposed method also can well resist attacks such as Gaussian noise, salt & pepper noise, speckle noise, Gaussian filtering, median filtering and average filtering. And the watermarks extracted from print-scan experiment can be well recognized. In the phase of watermark extraction, original image is not needed. The watermarking technology proposed can be widely used in copyright protection of digital and printed images. [ABSTRACT FROM AUTHOR]

Low-speed vehicles have a very high contribution to air pollution in China due to their considerable numbers, especially in the fringe area of city. In China, the low-speed vehicles emissions greatly exceed those of trucks and passenger cars because of their lower emission limits. Emissions of CO, HC, NOx and PM by low-speed vehicles accounted for 0.5%, 4.1%, 7.3% and 4.8% of the total vehicle emissions in 2012 in China. In 2005, the China Ministry of Environmental Protection issued the first-phase and second-phase emission standard (standards GB19756-2005 and GB19757-2005, respectively). However, there were not many research-based data about the emission characteristics of low-speed vehicles. In this study, a Portable Emission Measurement System (PEMS), which is comprised of a regulated gaseous emission analyzer (SEMTECH-DS) and an electrical, low-pressure impactor (ELPI), was introduced to study the emission characteristics of low-speed vehicles in real road. Six low-speed vehicles were measured on national and rural roads using PEMS, which can measure CO, HC, NOx and PM emissions. The results indicated that vehicle speed had a very big impact on pollutant emissions on both national and rural roads. Emissions on rural roadways were much more variable than those on national roadways because of the variability in vehicle speed. The ratios of acceleration and deceleration modes were not very high both on national and rural roads (28.48% and 33.76%, respectively). The emission factor of four pollutants was highest in acceleration mode on both national and rural roads. The CO, HC, NOx and PM emission factors in acceleration mode were 1.86, 1.32, 1.57, 1.22 times those in cruise mode, respectively. The CO, HC, NOx and PM emission factors in acceleration mode were 2.30, 1.42, 3.09, 1.39 times those in deceleration mode, respectively. The size distributions of particles emitted from low-speed vehicles were similar on national and rural roads. The ratio of coarse mode particles was very low (0.15 % and 0.16%, respectively) of the total particle number concentration on national and rural roads. Comparing the number concentration of particles emitted on national and rural roads, the particle-number concentration on rural roads was higher 32.0% than that on the national roads. Especially for particles of diameter 0.32 μm, the number concentration was 62.2% higher than that on the national road, probably due to the poor combustion in the engine cylinders. This report could provide some reference for future emission control policies for low-speed vehicles. [ABSTRACT FROM AUTHOR]

Objective:To investigate the effects of autophagy on cisplatin-induced cervical cancer Hela cell death, and observe impact of Beclin 1 on sensitivity of Hela cells to cisplatin in vitro. Methods: Hela cells were treated with cisplatin in different concentration, and MDC dyeing was explored to measure the formation of autophagic vacuoles and Western blot was used for detecting protein expression of Beclin 1 and LC3. The eukaryotic expression vector of Beclin 1 was transfected via lipofectamine into Hela cells. MTT assay was employed to observe the effect on the IC50 value of cisplatin, and flow cytometry was employed to observe the percentage of autophagic cells and apoptotic cells. Results: The autophagy vesicles were increased and the expression of Beclin 1 and LC3 were significantly improved in a dose-dependent manner in Hela cells treated with cisplatin (P<0.05). The eukaryotic expression vector pcDNA3.1 ( + )-Beclin1 significantly improved the expression of Beclinl in Hela cells (P<0.05). MTT assay showed the IC50 value of cisplatin decreased from 1.0 mg/L to 0.5 mg/L(< 0.05), and more autophagic cells and apoptotic cells were identified in pcDNA 3.1 ( + )-Beclin1 group than the other groups. Conclusions: Autophagy play an important role in the process of cisplatin-induced Hela cells death, and Beclin 1 overexpression can increase the sensitivity of Hela cells to cisplatin. [ABSTRACT FROM AUTHOR]

The falling film absorption heat transfer of water-lithium bromide on the outer surface of vertical tubes is experimentally studied. The two enhanced heat transfer tubes are designed in terms of the field synergy principle. Their absorption heat transfer performance is compared with that of the smooth copper tube as well to investigate the enhancement effect in absorption process. The control variables for the experimental study were solution mass flow rate, solution concentration and temperature, cooling water temperature and mass flow rate. The experimental results indicate that two heat-enhanced tubes can considerably improve the LiBr/H2O falling film absorption performance. The heat transfer enhancement ratios for the two tubes are 20% and 50% respectively at lower falling film Reynolds number, and increase with the Reynolds number of cooling water. The inherent physical mechanism of heat transfer enhancement is analyzed with respect to the field synergy principle and the wavy nature of the falling film. It is discovered that both the intersection angle between velocity and temperature gradient and the heat resistance caused by film thickness have an effect on convective heat transfer. [ABSTRACT FROM AUTHOR]

The accurate calculation of the burning surface during the grain burnback is the basis for the ballistic performance calculation of solid rocket motor. The overload conditions of the motor can significantly affect the burning surface area, grain burnback and internal ballistic performance of the motor. The minimum distance function (MDF) method is suitable for calculating the burnback process of complex three-dimensional grains, and has high precision. Based on the MDF method, this paper takes the common tube and star grain in engineering applications as the research object, and for the rocket motor working environment with high lateral overload, the burning surface area, grain burnback and internal ballistic performance of the motor are calculated and obtained. On this basis, the influence of overload on the burning surface area and internal ballistic performance of the motor is comprehensively analyzed.

In the spectral mean cross section measurements of 197Au(n,2n)196Au and 45Sc(n,2n)44Scm, the activation products 196Au and 44Scm have low activity and shorter halflife, but the activation products 198Au and 46Sc from neutron capture reactions of 197Au(n,g) and 45Sc(n,g) have strong activity and longer halflife, which results in poor signaltonoise ratio of gammaray characteristic peaks, and increases the measuring uncertainty of 196Au and 44Scm activity. In order to accurately measure 196Au and 44Scm, a radioactive activity measuring device based on anticoincidence principle was developed. The main techniques used were as follows: Firstly, liquid flash measurement system has been used to detect the betaray emitted by the decay of 198Au and 46Sc, basing on the anticoincidence principle, the betaray would be used to suppress Compton background caused by gammarays emitted by the two nuclides above; Secondly, a portable antiCompton spectrometer has been constructed using a ring sodium iodide crystal, and the Compton background caused by the decay of 198Au and 46Sc has been further suppressed by the anti-Compton principle. Thirdly, a thin layer of lead shield has been placed between the radioactive source distributed evenly in the liquid scintillation and a wellshaped high purity germanium (HPGe) crystal to absorb the Xrays emitted by the decay of the 196Au, as results, the coincidence between the Xrays and the characteristic gammarays emitted by 196Au in the HPGe crystal reduces significantly, and the detection efficiency of this measurement device for 196Au increases too. By using the digital spectrometer, the liquid flash measurement system and the antiCompton spectrometer integrated into one, the anticoincidence effect could be superimposed and good experimental results were obtained. For 198Au and 46Sc, the anticoincidence inhibition ratio is 871% and 869% respectively. The detection efficiency for 44Scm is 313%. After increasing the shielding layer, the detection efficiency for 196Au increases greatly, from 5.5% when the shielding layer is not available up to 11.9%. Under the condition of strong isotope interference (198Au or 46Sc of 02 MBq), the minimum detectable activity (MDA) of 24 h detecting to 196Au is less than 07 Bq, and to 44Scm is less than 03 Bq. Applying the double anticoincidence measuring device established in this paper to the activity measurement of 196Au and 44Scm could effectively reduce the uncertainty of 197Au(n,2n)196Au and 45Sc(n,2n)44Scm average crosssection measurement.

Objective To investigate the dysregulated genes, pathways and networks involved in type 2 diabetes-derived brain dysfunctions via performing whole transcriptome sequencing on the cerebral cortex of db/db and wild-type (WT) mice. Methods Male db/db and WT mice were divided into two groups (n=9). The body weight and blood glucose were measured at week 8 and 24. The 24-week-old animals were sacrificed for cerebral cortex collection. RNA-sequencing and analysis of differentially expressed genes (DEGs), GO functional enrichment, KEGG pathway enrichment and PPI network were performed. Results A total of 306 differential transcripts, including 178 up-regulated and 128 down-regulated ones were identified in the db/db mice as compared to WT ones. Among all differentially expressed genes, 43 genes (such as Clcnka and Trim17) were found to be up-regulated and 59 genes (such as Arih1 and Nectin-3) were down-regulated. The protein-protein interaction network was constructed with thirteen nodes as hub genes. All the nodes were down-regulated genes and majorly belonged to mitochondrially encoded families. The GO functional enrichment showed changes in various categories as compared to WT. KEGG enrichment analysis revealed that target genes were mainly enriched in metabolic pathways, Parkinson's disease, Alzheimer's disease, and the involved DEGs mainly regulate oxidative phosphorylation process. Conclusions The relationship between type 2 diabetes and central nervous system impairments, and the potentially related genes, pathways and networks are identified.

FBG(Fiber Bragg Grating) strain sensors based on similar material were designed according to the size of the geological mechanics model test, which can detect transverse, longitudinal and tangential strain synchronously. Then 7 FBG strain sensors were pre-embedded successively at left of laneway surrounding rock. Whereafter, fiber optics sensing network was built by adopting WDM (Wavelength Division Multiplexing) to real-timely monitor strain of the model test. The results detected by FBG strain sensors indicate that the radial strain of deep laneway surrounding rock does not descent with distance to laneway in laneway excavating experiment, while it presents as undulant arrangement , and the radial strain still presents as undulant arrangement with the distance to laneway in laneway excavating experiment after overloading experiment. Splitting the model, zonal disintegration of deep laneway wall rock under high ground stress is observed successfully, which validates that the FBG strain sensors are reliable. [ABSTRACT FROM AUTHOR]

We screened and identified an endophytic bacterium that could efficiently degrade PAHs, which would expand the library of polycyclic aromatic hydrocarbons (PAHs) degrading microorganisms and reduce the pollution risk of crops. Its degradation mechanism and colonization performance were preliminarily examined. The results showed that strain PX1 belonged to Stenotrophomonas maltophilia . The strain had broad spectrum ability to remove PAHs. In PAH mineral salt (MS) media, almost 100% naphthalene was degraded by strain PX1 after 7-d incubation. In a cultivation system solely containing phenanthrene of 50.0 mg·L -1 , pyrene of 20.0 mg·L -1 , fluoranthene of 20.0 mg·L -1 or benzo[a]pyrene of 10.0 mg·L -1 , the degradation efficiency of phenanthrene, pyrene, fluoranthene and benzo[a]pyrene by strain PX1 reached 72.6%, 50.7%, 31.9%, and 12.9%, respectively. Pyrene was selected as PAHs model to study the degradation characteristics of strain PX1. Enzyme activity tests showed that the activities of phthalate dioxygenase, catechol-1,2-dioxygenase, and catechol-2,3-dioxygenase in strain PX1 were induced by pyrene. Some metabolic intermediates such as 4,5-epoxypyrene, 4,5-dihydroxypyrene, gentilic acid/protocatechuic acid, salicylic acid, cis-hexadienedioic acid/2-hydroxymyxofuroic acid semialdehyde, cis-2'-carboxyphenylpyruvic acid, 1-hydroxy-2-naphthoic acid, and salicylaldehyde were detected during the degradation of pyrene by strain PX1. Results of the seed soaking experiment showed that strain PX1 could efficiently colonize in Ipomoea aquatic and Triticum aestivum. After inoculated with strain PX1, the growth of I. aquatic and T. aestivum was significantly increased, and the pyrene concentration in I. aquatic , T. aestivum and MS media was reduced by 29.8%-50.7%, 52.4%-67.1% and 8.0%-15.3%, respectively. Our results suggested that strain PX1 degraded pyrene mainly through 'salicylate pathway' and 'phthalate pathway', and could be colonized into plants and promote plant growth.

Nitrogen is the most limiting nutrient for ecosystems. The natural abundance of δ 15 N ( 15 N/ 14 N) can efficiently indicate ecosystem nitrogen cycling processes. We investigated the interannual variations in natural abundance of δ 15 N in soil-plant system and soil net nitrogen mineralization in a meadow steppe of Inner Mongolia. Results across the four sampling years (2017-2020) showed that the content of soil NO 3 - -N (9.83-14.79 mg·kg -1 ) was significantly higher than that of NH 4 + -N (3.92-5.00 mg·kg -1 ) and that δ 15 N value of soil NH 4 + (13.3‰-18.3‰) was significantly higher than that of NO 3 - (3.76‰-6.14‰). The δ 15 N value of soil NO 3 - was negatively correlated with soil NO 3 - content. The δ 15 N value of soil NH 4 + was relatively higher in the dry years, while the δ 15 N value of soil NO 3 - significantly decreased in the wetter and drier years. Soil net mineralization and ammonification rates were significantly higher in the dry years than that of the wet years, while soil nitrification rates showed no correlation with annual precipitation. The δ 15 N values of plants were not related to that of soils, but nega-tively correlated with plant nitrogen content. Both δ 15 N values and nitrogen contents were significantly and positively correlated between the leguminous and non-leguminous plants, suggesting that legume could facilitate nitrogen uptake of non-leguminous plants. These results could provide supporting data for nitrogen cycling and their responses to changes in precipitation in grassland soil-plant systems.

Objective: To study the percentage of the measured values of the main pulmonary ventilation function parameters in their predicted values based on Zapletal equation among healthy children aged 5-14 years in Kunming, China, and to provide a basis for accurate judgment of pulmonary ventilation function in clinical practice., Methods: A total of 702 healthy children aged 5-14 years (352 boys and 350 girls) from Kunming were enrolled. The Jaeger spirometer was used to measure the nine indices:forced vital capacity (FVC), forced expiratory volume in one second (FEV1), ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC), maximal mid-expiratory flow (MMEF), forced expiratory flow at 25% of forced vital capacity (FEF25), forced expiratory flow at 50% of forced vital capacity (FEF50), forced expiratory flow at 75% of forced vital capacity (FEF75), peak expiratory flow (PEF), and maximal voluntary ventilation (MVV). The values obtained from the Zapletal equation of predicted values provided by the spirometer were used as the predicted values of children, and the percentage of measured values in predicted values was calculated., Results: In the 702 children, the percentages of the measured values of the main pulmonary ventilation function parameters PEF, FVC, FEV1, FEV1/FVC, and MVV in their predicted values fluctuated from 102% to 114%, 94% to 108%, 98% to 113%, 98% to 107%, and 141% to 183% respectively. As for the main airway velocity parameters, the percentages of the measured values of FEF25, FEF50, FEF75, and MMEF in their predicted values fluctuated from 98% to 116%, 85% to 102%, 71% to 98%, and 83% to 100% respectively. The percentages of the measured values of PEF, FVC, FEV1, FEV1/FVC, MVV, FEF25, FEF50, FEF75, and MMEF in their predicted values had the lower limits of normal of 88.2%, 88.4%, 92.0%, 94.4%, 118.5%, 82.9%, 70.0%, 62.1%, and 70.1% respectively., Conclusions: There are differences between pulmonary ventilation function parameter levels and normal values provided by Zapletal equation in healthy children aged 5-14 years in Kunming. As for the pulmonary ventilation function parameters of PEF, FVC, FEV, FEV1/FVC, MVV, FEF25, FEF50, FEF75, and MMEF in these children, the lower limits of normal of measured values in predicted values may be determined as 88.2%, 88.4%, 92.0%, 94.4%, 118.5%, 82.9%, 70.0%, 62.1%, and 70.1% respectively.

Objective: To investigate the clinical feature, diagnostic and therapeutic experience of autoimmune pancreatitis (AIP)., Methods: Twenty-one patients with AIP treated in the First Affiliated Hospital, Harbin Medical University from January 2006 to July 2014 were analyzed retrospectively. There were 15 men and 6 women among the 21 cases and the age ranged from 36 to 64 years. The characters of diagnosis and treatment of AIP were explored through clinical symptoms, imaging features, serologic test results, diagnostic treatment, and histopathologic characteristics., Results: All the patients showed obstructive jaundice and upper abdominal pain to different extents as major manifestations and the levels of serum IgG4, CA19-9, CEA were elevated in 16 cases (76.2%), 6 cases (28.5%) and 3 cases (14.2%), respectively. CT showed diffuse enlargement of the pancreas in 9 cases, localized pancreatic head enlargement in 3 cases and focally pancreatic mass in 9 cases. AIP was confirmed by extrapancreatic involvement, radiological and serological results plus biopsy in 11 cases (52.4%), interpretation of response to steroid in 3 cases (14.3%) and open laparotomy in 7 cases (33.3%). Surgery included choledochojejunostomy in 3 cases, cholecystojejunostomy in 1 case, pancreaticoduodenectomy in 2 cases and distal pancreatectomy combined with splenectomy in 1 case. The pathologic results displayed massive lymphocytes and plasma cells infiltration in the pancreatic tissues as well as parenchymal fibrosis. Except for 1 patient who had no symptom, the regular steroid therapy was performed (oral prednisone) and all the patients were cured. The follow-up time range was from 3 to 93 months, 4 cases (19.0%) were recurrent followed by the symptoms alleviated after the steroid was applied again., Conclusions: AIP is rare and characterized by non-specific clinical manifestations so that the early diagnosis is difficult with a high misdiagnosis rate. The clinicians should strengthen the recognition of AIP and the definite diagnosis depends on the combination of clinical manifestations, radiological, serological and histopathological results so as to avoid the unnecessary operation.

Objective: To study the expression of cyclooxygenase-2 (COX-2) in esophageal carcinoma and its correlation with microlymphatic density (MLD), and to investigate the clinicopathological and prognostic significance of COX-2 and MLD in patients with esophageal cancer., Methods: COX-2 expression and MLD were detected by immunohistochemistry in 100 cases of esophageal squamous cell carcinoma. Follow up was available in 76 patients. Multivariable Cox regression was used to analyze the association between the laboratory indices and overall survival of patients with esophageal carcinoma., Results: COX-2 expression was present in 73% of patients. MLD in patients with high COX-2 expression (99.71±39.62) was significantly higher than that in those with low or no COX-2 expression (80.22±30.36) (P<0.05). No correlations were observed between the over expression of COX-2 and clinicopathologic parameters including tumor size and lymphatic metastasis (P<0.05). However, MLD was associated with lymphatic metastasis and the depth of invasion (P<0.05, P<0.01). In the 76 patients with followed up, the median survival was 25.5 months. Cox regression showed that the COX-2 expression, histological grade of the tumor and MLD were risk factors of overall survival of esophageal carcinoma., Conclusions: COX-2 may contribute to the lymphangiogenesis in the tumor. COX-2 may be a new target point for the treatment of esophageal carcinoma. COX-2 expression and microlymphatic vessel density are of significant prognostic value for esophageal carcinoma.

Objective: To investigate the effects of glutamine on the changes of nuclear factor (NF)-kappaB and lung pathology in acute lung injury., Methods: Forty SD rats underwent injection of lipopolysaccharide (LPS) 5 mg/kg into the femoral vein, and were randomly divided into 4 equal groups: Group B: undergoing injection of glutamine 0.75 g/kg into the femoral vein 1 h before LPS injection, Group C undergoing injection of glutamine and LPS simultaneously, and Group D undergoing injection of glutamine 1 h after LPS injection, and Group E without glutamine injection. Another 10 rats underwent injection of normal saline to be used as controls (Group A). Four hours after the LPS injection the rats were killed with their lungs taken out RT-PCR was used to detect the level of nuclear factor (NF)-kappaB mRNA expression. ELISA was used to detect the tumor necrosis factor (TNF) - in lung. The activity of superoxide dismutase (SOD) was examined by hydroxylamine method, and the malondialdehyde level was determined by thiobarbituric acid (TBA) method., Results: The lung NF-kappaB mRNA expression levels and TNF- levels of Groups B, C, D, and E were all significantly higher than that of Group A (all P < 0.01). The lung NF-kappaB mRNA expression levels and TNF- levels of Groups C and D were all significantly lower than those of Group B (P < 0.01). However, there were no significant differences in lung NF-kappaB mRNA expression level and TNF- level between Group B and Group E (both P > 0.05). The SOD activity of Group B was significantly lower than that of Group A and the MDA content of Group B was significantly higher than that of Group A (both P < 0.05). The SOD activity levels of Groups C and D were significantly higher than that of Group B and the MDA content of Groups C and D were significantly lower than that of Group B (P < 0.01 or P < 0.05). However there were no significant differences in lung SDD activity and MDA content between Groups B and E (both P > 0.05). Obvious inflammatory changes were seen in the lungs of Groups B and E at the similar extent. Only slight infiltration could be seen in Groups C and D. The lung of Group A was normal., Conclusion: Early glutamine administration protects the lung against acute LPS injury. The mechanism may be inhibition of the overexpression of NF-kappaB mRNA.

Objective: To study the effect of the repair of rabbit articular cartilage defects by the composite of chondrogenic induction of autologous MSCs and autologous "two-phase" bone matrix gelatin (BMG)., Methods: Twenty-four healthy adult New Zealand rabbits weighing 2 to 3 kg were divided into group A, B and C with 8 in each. Autologous MSCs derived from group A were cultured in vitro and observed under inverted phase contrast microscope when enough cells through trypsinization transferring in vitro were obtained. Then the growth curves of 1, 3 and 5 passage culture of MSCs were drawn. The 3rd passage MSCs were induced into chondrogenic differentiation by adding TGF-beta1 (10 ng/mL), IGF-1 (10 ng/mL) and vitamin C (50 ng/mL) in vitro. At 8 days after induction, the features of chondrocytes were observed under inverted phase contrast microscope,and immunohistochemical staining and Mallory staining were made. Getting out part of the ilium of group A and B, according to the method of Urist, the "two-phase" BMG was acquired. Chondrogenic induction of autologous MSCs was inoculated into the corresponding BMG to set up a composite of cell-carrier, and then it was observed through scanning electric microscope after 3 days of culture. The model of articular cartilage defects of rabbits was made: in group A,autologous cell-carriers were implanted; in group B, there only existed autologous BMG; in group C,there was nothing. At 8, 12 weeks after operation, the gross, HE staining and immunohistochemical staining were made,and grading scales were evaluated according to Wakitani histological grading method., Results: Features of MSCs were as follows: the shape of primary cells was shot-spindled and of passage cells was long. As to the growth curves of 1, 3 and 5 passage culture of MSCs,passage cells grew slowly for 3 days after being passaged and went into log-growth during the 3rd and the 7th days and into plateau later, but the 3rd passage cells grew best. Observation of MSCs after chondrogenic induction was performed: the shape of cells was elliptical and the effect of induction was verified by the positive results of collagen type II, S-100 and Mallory staining. Under scanning electric microscope,the structure of BMG was good and cells were observed growing in it well. As far as repair of articular cartilage defects are concerned at 8, 12 weeks after transplantation, the defects in group A were repaired by the hyline-like tissue and the structures of the cartilage surface and normal cartilage were in integrity,and immunohistochemical staining of collagen type II was positive, while those in group B and C were repaired by the fibrous-like tissues and the surfaces were irregular. In Wakitanni histological score, at 8 weeks after operation, group A was (3.50 +/- 1.51) points, group B was (10.00 +/- 1.41) points and group C was (12.00 +/- 0.93) points; at 12 weeks, group A was (1.13 +/- 0.99) points, group B was (8.38+/-1.30) points, and group C was (10.13 +/- 1.64) points. At different time points,group A was significantly better than group B and C, showing significant differences (P < 0.05)., Conclusion: Induced autologous MSCs and the composite withautologous "two-phase" BMG have the function to repair articular cartilage defects, and they are better than autologous BMG transplanted only or nothing transplanted.

Objective: To explore the relationship of monitoring CD14(+) monocyte human leucocyte antigen (locus) DR (HLA-DR) and the outcome in the early stage of sepsis., Methods: Thirty-six definitely diagnosed septic patients in intensive care unit (ICU) were included. CD14(+) monocyte HLA-DR levels were detected by flow cytometer on the first day of the study, and acute physiology and chronic health evaluation II (APACHE II) scores were evaluated. Their clinical values in predicting the outcome of the disease were assessed through correlation analysis., Results: Among 36 sepsis patients CD14(+) monocyte HLA-DR level<30% was found in 6 patients (16.67%). The average APACHE II score was 24.17+/-4.45 (r=0.212, P=0.687), all of them die, CD14(+) monocyte HLA-DR level <40% was 27.78% (10/36), the scores of APACHE II score was 23.50+/-4.30 (r=-0.0251, P=0.484), and the mortality rate was 80% (8/10)., Conclusion: CD14(+) monocyte HLA-DR level <30% is an immunosuppressive index. In predicting the outcome of sepsis, it might be better than APACHE II scores. Immunosuppression is primarily found in the early stage of sepsis, suggesting that the classical compensatory anti-inflammatory response syndrome (CARS) hypothesis needs to be revised and improved.