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In order to test the accuracy of the weapon hitting the target, it is very important to locate and measure the spatial coordinates of the falling point target. Aiming at the needs of space coordinate positioning and measurement of targets falling into the sea/ground plane, this paper studies a positioning method of UAV camera combined with target, and uses the principle of homography transformation to calculate the space coordinates of targets. The influence of pixel error on the positioning method is simulated by Monte Carlo method, and the shooting attitude range meeting the measurement requirements is determined by simulation. The results show that the positioning method of UAV camera combined with target has high accuracy, which can meet the needs of landing target positioning and measurement.

Objective To study the relationship between the key influencing factors and the short, medium and long term blood demand, so as to provide basis for building a blood demand prediction model with less prediction error and practical guidance. Methods Through literature research, the influencing factors of blood demand were preliminarily determined. Questionnaires were designed and distributed to relevant experts, and factor analysis was carried out on the survey results to obtain key influencing factors through Delphi method. Results Through literature research, 19 influencing factors of clinical blood demand were obtained, including policy factors, medical service demand, medical technology level, regional population, population characteristics, population structure, medical resource, number of beds, culture, natural environment, operation, patients outside the region, blood use in different departments, blood infusion, time trend, emergencies and disasters, the condition of disasters, hospitals in disaster area, limited diagnosis and treatment ability. Through Delphi method and data analysis, six key factors affecting blood demand were obtained, namely sudden disaster, medical resource, environmental factor, population, bed number and blood infusion. Conclusion The influence of key factors on clinical blood demand was divided into multiple hierarchies. Blood infusion and sudden disaster were short-term influencing factors. Medical resource, population and number of beds were medium influencing factors. Environmental factor was long-term influencing factor. Short, medium and long-term influencing factors were interrelated, and have different impacts on clinical blood demand. Based on the interaction relationship, a three-dimensional mathematical model of influencing factors of clinical blood demand was established, which provided a preliminary research basis for building a blood demand prediction model with less prediction error and practical guidance.

Cereals and pulses are the most important food and its raw materials. Each year, more than 450 million tons of cereals and 19 million tons of pulses (excluding soya beans) are traded in the international market. As the most authoritative and comprehensive standards developing organization, International Organization for Standardization (ISO) elaborates the international standards for cereals and pulses, which plays an important role in coordinating and promoting international trade, improving trade efficiency, and ensuring the quality and safety for grain. This article introduces the work scope, organizational structure, and standard framework of the Cereals and pulses Subcommittee of ISO, as well as the achievements of China's participation in international standardization of grains. In the future, the ISO Cereals and pulses Subcommittee will work with its members to focus on nutrition and health products, new testing technologies for quality and safety, as well as food loss and waste.

Monte Carlo tree search (MCTS) has gained great success in low discrete control tasks.However,there are many tasks in real life that require selecting action sequentially in continuous action space.Kernel regression UCT (KR-UCT) is a successful attempt in low-dimensional continuous action space by using a pre-defined kernel function to exploit the similarity of different continuous actions.However,KR-UCT gets a poor performance when it comes to high-dimensional continuous action space,because KR-UCT does not use the interacting information between agent and the environment.And when it interacts with the environment,KR-UCT needs to perform a lot of simulations at each step to find the best action.In order to solve this problem,this paper proposes a method named kernel regression UCT with policy-value network (KRPV).The proposed method can filter out more representative actions from action space to perform MCTS and generalize the information between different states to pruning MCTS.The proposed method has been evaluated by four continuous control tasks of the OpenAI gym.The experimental results show that KRPV outperforms KR-UCT in all tested continuous control tasks.Especially for the six-dimensional HalfCheetah-v2 task,the rewards gained by KRPV are six-timesof that of KR-UCT.

Crop root system plays an important role in nitrogen uptake. In this study, two rice varieties, conventional rice variety Huanghuazhan (HHZ) and super hybrid rice variety Yangliangyou 6 (YLY6), were grew hydroponically under high nitrogen (HN) and low nitrogen (LN) treatments to investigate the changes of root characteristics and their relationships with nitrogen accumulation at seedling stage. Compared to HN, LN significantly decreased the total N accumulation in HHZ by 19.7% and had no substantial effect in YLY6. Under LN, root dry weight, the total root length, root surface area, and root tips in YLY6 significantly increased by 41.3%, 57.1%, 74.9%, and 20.6%, respectively. However, these four morphological parameters had no significant change in HHZ. Under LN, root diameter and root cortical area in YLY6 significantly increased by 12.4% and 24.2%, respectively. However, the two parameters and root stele diameter in HHZ significantly reduced by 12.0%, 21.9%, and 11.4%, respectively. In YLY6, LN significantly up-regulated the relative expression level of root ammonium transporter genes (AMT2;1, AMT2;3, AMT3;1, and AMT3;2) by 195.6%, 29.3%, 314.9%, and 388.9%, respectively, and increased the relative expression level of glutamine synthetase gene GS1;1 by 158.2%. However, LN had no effect on the relative expression level of the five genes in HHZ. Total nitrogen accumulation was significantly and positively correlated with the root characteristics (but thickness of root cortical sclerenchyma) and expression of above-mentioned genes under LN. These results indicated that the enhanced positive responses of above-mentioned root characteristics contributed to high nitrogen accumulation in YLY6 seedlings under LN. Developing varieties with root positive responses to nitrogen reduction should be a considerable target for green rice production. [ABSTRACT FROM AUTHOR]

Nanorod Ag doped hydroxyapatites (Ag-HA) were synthesized by precipitation and hydrothermal method. Crystal structure, morphology and antibacterial property of prepared samples with silver contents prepared by different synthesis methods were investigated. The results show that Ag doped hydroxyapatites synthesized by hydrothermal method possess a higher length to diameter ratio, higher degree of crystallinity, better dispersion,larger grain size and smaller unit cell parameters. The average crystal size of prepared samples by precipitation method at 70℃ and hydrothermal method at 180℃ are (22.7±0.7)nm and (50.7±0.9)nm, respectively. In addition, adding silver into hydroxyapatite may increase grain size and unit cell parameters. When silver content is 1.30%, average grain size and unit cell parameters are (53.7±0.9)nm and a =0.9465nm, c =0.6970nm, respectively. Antibacterial test results indicate that Ag-HA exhibits good bactericidal property against Escherichia coli ( E.coli ) and Staphylococcus aureus ( S.aureus ). The antibacterial rate is 100% when silver content varies after different hours(1, 3, 6, 12, 24h).

Drought is the most common and complex meteorological disaster in the world, which weakens the carbon sink function of terrestrial ecosystem. Exploring the response of vegetation to drought and choosing sensitive factors for drought detection will be helpful to obtain the impact of drought on vegetation and to understand the response process and the mechanism of vegetation to drought stress. Based on the Solar-Induced chlorophyll Fluorescence (SIF) and the standardized precipitation evapotranspiration index (SPEI), a maximum correlation coefficient method was used to investigate the response of vegetation photosynthesis to meteorological drought in China during the growing season from 2000 to 2018. Sensitivity and response time scale of vegetation to drought was compared for different drought levels and different vegetation types. The results showed that: (1) about 75.05% of total areas of China had a significant positive correlation between SIF and SPEI. These areas were mainly distributed in the northeast, southwest and Qinghai Tibet Plateau of China. The response time scale of most regions to SPEI was mainly medium and short term. (2) The proportion of SIF to SPEI was the lowest in spring, the highest in summer, and slightly decreased in autumn. The response time scale to drought was mainly short-term in spring, while the region with long response time scale in summer was increased compared with in spring. (3) The semi-arid region was the most sensitive to drought, while the arid region was the weakest. The response time scale of different climatic regions to drought was mainly short-term. (4) The selected vegetation types responded to drought in a short time scale. Grassland was the most sensitive to drought, while woodland and cropland were relatively weak. Besides, broad-leaved forest was more sensitive to drought than coniferous forest. The results showed that under different drought gradients and different vegetation types, SIF could quickly reflect the impact of environmental stress on vegetation photosynthesis. [ABSTRACT FROM AUTHOR]

Aiming at the problems of high-cost, untimely and insufficient overseas material transportation and delivery, in order to effectively plan the overseas anti-terrorism offshore supply scheme, this paper explores the efficient security mode of transportation and delivery, and establishes an overseas delivery scenario for anti-terrorism operations of bases in a certain area. By closely combining the characteristics of overseas transportation and delivery, Anylogic multi-agent is used to carry out the simulation is carried out, and two sets of overseas delivery schemes are compared. The results show that the model has good applicability for overseas material transportation and delivery, which can reduce the delivery cost, and also has certain reference significance for the exploration of overseas delivery modes. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemiological characteristics of mumps in Fujian Province from 2011 to 2020, this paper provides a basis for the formulation of effective prevention and control measures and the evaluation of prevention and control effects. Methods All the reported mumps were collected through National Notifiable Disease Information Management System, 2011-2020. Throat swab specimens were collected for cells culture, genotyping and gene sequence analysis on mumps virus(MuV). Descriptive epidemiological method was used to analyze the feature of time, geography and population. Results The average incidence of mumps in Fujian Province was 14.49/100 000, and the annual incidence was 4.69/100 000-43.17/ 100 000, and the highest incidence was in 2011. Since 2013, the incidence of mumps decreased significantly; Mumps cases have been reported in 9 prefecture-level cities and in Pingtan County, and no regional characteristics existed. Two seasonal peaks occurred regularly in years, the first peak was from April to July, the second small peak was from November to January in the next year. There were more males than females of incidence, with a male-to-female ratio of 1.74 to 1. There was significant difference between male and female (P<0.01) . Most of the patients were students and children (72.71%) . The age of the patients ranged from 5 to 14 years old, and decreased with the increase of age. The concentrated outbreaks mainly occurred in primary and secondary schools, with 30.43% (21/69) in rural primary and secondary schools lower than 69.57% (48/69) in urban primary and secondary schools and secondary education schools. Program from the pathogen surveillance showed that the transmission chain of two different genotype F and G Mumps virus existed in Fujian. Conclusion The incidence of epidemic mumps decreased in Fujian, 2010-2020. The the prevention and control should be strengthened in key places such as schools and nurseries, so as to avoid the occurrence of aggregated epidemic. Two different genotypes of F and G occured in Fujian Province, the surveillance of pathogeny should be strengthened. [ABSTRACT FROM AUTHOR]

Objective To study the clinical features, auxiliary examination, diagnosis and treatment, and prognosis of cerebral amyloid angiopathy - related inflammation (CAA - ri). Methods and Results Two elderly female cases with CAA-ri during February 2017 to February 2018 in our hospital were reported. Both of them manifested with cognitive impairment, gait abnormality and decreased daily life ability. Lumbar puncture of 2 cases showed the pressure of cerebrospinal fluid (CSF) was normal, white blood cell (WBC) count was generally normal and protein quantification was increased (988 and 975 mg/L). One case presented decreased CSF amyloid- β protein 40 (A β 40) and 42 (A β 42), and the other one had decreased Aβ42. One case was apolipoprotein E (ApoE) ε3/ε3, and the other was ε3/ε4. Brain MRI showed long T1 and long T2 abnormal signals with flaky fusion, and susceptibility-weighted imaging (SWI) showed multiple cortical and subcortical microhemorrhage. They were diagnosed as CAA - ri, and the symptoms were obviously improved after methylprednisolone implosive sequential therapy. Conclusions In addition to cognitive impairment, gait abnormality can also be the main clinical manifestation of CAA-ri. Typical imaging changes are white matter hyperintensity on T2WI and FLAIR fusion sequences, with multiple cortical and subcortical hemorrhagic lesions on SWI. Once the typical clinical and imaging changes meet the diagnostic criteria, the diagnosis of CAA-ri can be made without biopsy. Immunotherapy is effective for most patients. [ABSTRACT FROM AUTHOR]

Developing new octoploid Trititrigia is of great significance for using Thinopyrum intermedium to the genetic improvement of common wheat. Ten octoploid Trititrigia accessions, i.e., Shannong TE256, Shannong TE259, Shannong TE261, Shannong TE262, Shannong TE263, Shannong TE265, Shannong TE266, Shannong TE267-1, Shannong TE270, and Shannong TE274, were developed from the progenies of the cross between Thinopyrum intermedium and common wheat variety 'Yannong 15'. In this study, cytological methods and genomic in situ hybridization (GISH) were employed to determine cytological stability and chromosome constitutions of the 10 octoploid Trititrigia accessions. Mitotic observation indicated that most plants of octoploid Trititrigia had 56 chromosomes and a few had 54 or 55 chromosomes. Chromosomes in most pollen mother cells of plants with 2n = 56 formed 28 bivalents, showing a high degree of cytogenetic stability, simultaneously, univalents, trivalents and tetravalents appeared occasionally at meiotic metaphase I. At meiosis anaphase I (PMC AI), most chromosomes segregated equally to the two poles except for several univalent chromosomes moving ahead in very few cells. Fourteen Th. intermedium chromosomes were observed to be added to the whole set of common wheat chromosomes in each octoploid Trititrigia, and the alien chromosome constitutions of the 10 octoploid Trititrigia accessions were 2St+8JS+2J+2J-St, 2St+8JS+4J, 2St+8JS+2J+2J-St, 2St+8JS+2J+2J-St, 2St+8JS+2J+2J-St, 6St+4JS+2J+2J-St, 4St+6JS+2J+2J-St, 2St+8JS+4J, 2St+8JS+4J, and 4St+6JS+4J. These alien chromosome constitutions were different from those reported in octoploid Trititrigia, suggesting that the 10 octoploid Trititrigia accessions are novel materials and might be valuable in wheat breeding programs. [ABSTRACT FROM AUTHOR]

Rased on die analysis method from seepage mechanics, the coupling effect of coal-seam mining fissure, stress and methane flow was studied. The fissure of coal-seam and overlying rock, as well as mining stress and gas pressure were measured on site. Also, the interaction of these three parameters was comparatively analyzed. The results show that the permeability of cracked coal mass under mining is related to fissure width, connect situation, unevenness, spacing, normal stiffness and mining stress; methane flow in cracked coal mass is intimate to fissure development; and methane permeability is positively correlated to fissure width and negative to fissure spacing. Based on the coupling effect of mining fissure, stress and methane flow in front of working face, a mechanic model of cracked coal mass' mining stress and methane seepage was built. The model can provide the coupling effect of mining fissure, mining stress and methane flow in fractured coal-rock mass. [ABSTRACT FROM AUTHOR]

Objective: To study the association between the volume size of single follicular and iVF-ET/ iCSi outcomes, in which the ultrasound was used to observe the single follicular developmental state in natural cycles and minimal stimulation cycles. Methods: Clinical data of 1 480 women undergoing iVF-ET/iCSi in our center between April 2007 and May 2012 were retrospectively analyzed. They were divided into 5 groups according to the follicular volume size:group A,≥ 5.5 mL;group B,4.5-5.0 mL,group C,3.5-4.0 mL,group D, 2.5-3.0 mL,group E, 1.0-2.0 mL. The clinical outcomes were compared. Results: 1Follicular volume was significantly decreased with the mean diameter of single follicle on the day of hCG administration in 5 groups, in both non-stimulation protocol and minimal stimulation protocol (P<0.001). 2In natural cycles, the pregnancy rate and live birth rate were relatively low in group A (11.8%), while those rates in other four groups were 20.0%-25.0% and 15.8%-20.0%, but there were not significant differences in groups (P >0.05). in group A,the available transplantation embryo rate was high while the non-fertilization rate was low; the zero oocyte retrieval rate(32.6%) was higher than those in group C and group D(P<0.01); the available transplantation embryo cycle was merely 39.53%(17/43). In group B,the 2PN rate was high while the abnormal fertilization and the not-done fertilization rate were low; the non-fertilization rate was relative high while the available transplantation embryo cycle was merely 48.19% (40/83). The results of other C groups were better than group A generally. 3In minimal stimulation cycles, the pregnancy rates were high in group B and C (24.1% and 21.6%), but there were not significant differences when compared with three other groups (16.7%-17.8%, P >0.05). There were significant differences in the rates of fertilization, abnormal fertilization, good embryo and available transplantation embryo among five groups (P<0.05). The abnormal fertilization rate in group B was relatively high (15.4%) and the available transplantation embryo rate and the good embryo rate were highest (97.0% and 87.8%, respectively). The good embryo rate and the available transplantation embryo rate in group E were lowest (58.1% and 75.8%, respectively,P<0.01). The fertilization rate in group C was lowest and the abnormal fertilization rate was also lowest (3.0%,P<0.01). Conclusions:IVF-ET/ICSI outcomes may be better when the volume of single follicle was 2.5-5.0 mL(15.1-19.6 mm of oocyte diameter). However, it is necessary to have more well-designed and multicenter studies. [ABSTRACT FROM AUTHOR]

The aircraft model shows obvious time-varying characteristic due to the uncertainty of aerodynamic parameters. The fault diagnosis of the flight control systems is a difficult issue. A sensor fault estimation approach based on aerodynamic parameter identification and iterative learning is proposed by taking the longitudinal motion model of some unmanned aerial vehicle as the study subject. The augmented cubature Kaiman filter ( ACKF) is used for the aerodynamic parameter estimation so that the system model can be identified online. Once a fault comes up, the currently identified aerodynamic parameters are applied to system modeling in the local flight envelope, and a fault estimator is constructed using the iterative learning algorithm. Furthermore, a novel iterative learning algorithm based on the essence of extended state observer (ESO) is designed to improve the fault estimation speed. The fault simulation experiments are conducted to verify the feasibility and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The nuclear magnetic resonance (NMR) technique is a noninvasive and nondestructive way of probing water content in plants, and has been broadly used in the studies on plant-water relationship. In order to investigate water distribution in a living winter wheat plant, the T2 relaxation parameters of NMR were used to measure the moisture contents (MC) in leaf, stem, and spike of winter wheat. The results showed that the amplitude of T2 relaxation spectrum was linearly correlated to the mass of water in the plant sample. And according to the T2 relaxation properties of wheat leaf, stem, and spike, the T2 relaxation spectra could be divided into two components. The fresh weight could be estimated through linear regression using the peak areas of each component of T2 spectra. Then, the moisture contents of each organ could be obtained. To verify the moisture content estimation function, the moisture contents of organs of seven wheat varieties were measured with both NMR and traditional oven-drying methods. The root mean square error (RMSE) was adopted to measure the accuracy. The results showed that the RMSE of two kinds of measured moisture contents of leaf, stem and spike were 5.3%, 3.5% and 3.3%, respectively. The NMR detection method had high detection precision for moisture content. By comparison, the detected moisture contents in spike and stem were more precise, followed by leaf measurement. The larger error for wheat leaf was probably due to a relatively lower signal-noise ratio, and a reason for this might be the lower level filling degree relative to stem and spike. Then the method was applied to monitor the long-term and diurnal changes of the moisture contents in living wheat plants at different growth stages. The results showed that moisture content of the second upper leaf decreased from 79% to 54% during grain milk stage and ripening. The moisture content in flag leaf remained relatively stable, which kept at 78% and then decreased to 72% until the grain dough stage. The moisture contents of the first and second stems below spike also decreased from 69% to 60%. The nutriment in leaf and stem was activated and transferred into wheat grain during the stage of grain filling. This process was accompanied by a decrease of the moisture content in spike from 61% to 31%. The moisture contents of the flag leaf and second upper leaf decreased first and then increased during the stages of grain milk and ripening. At grain milk stage, leaves moisture contents were about 77% at 8:00 and reduced gradually to 74% at 14:00 (at 16:00 for flag leaf), then to 76% at 20:00. It means the moistures of leaves could recover to their initial state after decreased at grain milk stage. However, at ripening stage, the moisture content of flag leaf decreased from 70% at 8:00 to minimum (53%) at 16:00, then to 60% at 20:00. The second upper leaf showed the same tendency that the moisture content decreased from 66% to 45% and merely increased to 55% thereafter. Since the method based on NMR can continuously monitor the same wheat plant without destruction and invasion, this study can reveal the water dynamics and aging process of winter wheat more directly and precisely. The results will lay a theoretic foundation for the study on water consumption of winter wheat growing healthy and rational irrigation schedules. During next study, more wheat plants and high frequency detecting should be taken into account to demonstrate the general significance. At the same time, different environment conditions should be settled for a deeper exploration of the water distribution and movement within the wheat body. [ABSTRACT FROM AUTHOR]

Eco-environment flax/ polypropylene thermoplastic composite are prepared by compression molding process, in which the flax fibers as reinforcement and the matrix phases are come from polypropylene (PP) fibers. The effects of fiber length, molded temperature and holding time on the tensile and bursting performance of the composites are investigated. The results show that the molding temperature was the main factor to influence composite properties. The optimal tensile property of the flax/polypropylene composite is obtained in the parameters of fiber length 5 mm, molding temperature 180 °C and holding time 40 min. The bursting performance of the polypropylene/flax composites is come to the peak value when mentioned above parameters are 5 mm, 170 °C and 40 min. [ABSTRACT FROM AUTHOR]

In this article, a kind of near perfect reconstruction cosine modulated filter banks which could be used to receive wideband signal is raised. First, the design of filter banks is transformed to the design of prototype filter. Considering the problem of amplitude distortion among existing algorithms, this article adopts cost function to make transition band has square root cosine roll-off. Cut-off frequency of passband is adjusted to ensure that the cut-off frequency of prototype filter's 3dB passband is equal to that of ideal filter. In this article, close form solution expression of a cost function whose variable is filter factor is derived as well. To solve the problem of the high complexity of filter, a way based on iteration to solve prototype filter is adopted. The result of the simulation shows that modulated filter banks derived in this way perform better than those designed by existing method. [ABSTRACT FROM AUTHOR]

A mathematical model of thermal reversal oxidation of the low concentration methane was established in this paper. The computational fluid dynamics method was used to simulate the temperature distribution and methane concentration distribution under various operating parameters. The calculated values of methane conversion showed good agreement with the corresponding available experimental data. The model was used to investigate the effects of operational conditions such as the approach velocity and equivalence ratio on the oxidation of methane. The results show that the temperature distribution within the bed is substantially M-typed;the high temperature zone and the methane concentration distribution curve along the direction of gas flow move periodically; the greater the inlet methane concentration, the higher the temperature peak, the closer to the inlet end of the temperature curve and the wider the high-temperature region; if the premixed methane gas flow rate increases from 0. 15 m/s to 0. 70 m/s,the maximum temperature peak and the high temperature zone change little, because as the gas flow velocity increases, both the heat releasing in the reaction bed and the heat carried out by the flow increase. [ABSTRACT FROM AUTHOR]

Divided by whether environmental quality and resources utilization rate could be enhanced, enterprises are facing two developmental directions, which are traditional technological innovation (TTI) and green technological innovation (GTI). There exists a principal-agent relationship between government and enterprises in encouraging and guiding technological innovation. Based on the multitask principal-agent models proposed by Eugene Silberberg, the government's incentive contract assumption is formulated and the models are given a static analysis. Then, four suggestions are made about the government's incentives of green technological innovation, i.e., the government should make clear of its "green goal" in the incentive guidance of technological innovation, promote green technological innovation periodically, focus on enterprises' pilot work on green technological innovation and establish a guarantee mechanism for green technological innovation. [ABSTRACT FROM AUTHOR]

Because the fixed parameters of the extended state observer (ESO) reduce the estimation precision of "total disturbance" and control effect for the systems which the parameters of the controlled objects change largely and fast or there being serious and uncertain outside disturbance, an adaptive active disturbance rejection controller (ADRC) based on BP neural network was proposed. The significance of introducing adaptive ESO as well as the structure of ESO was analyzed, then the adaptive ESO which parameters are adjusted online by means of BP neural network was applied to ADRC. Simulations show that the improved ADRC has higher estimation precision, smaller range of controlling quantity, high robustness and anti-interference performance compared with conventional ADRC. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a multi-attribute group decision making method with unknown attributes' weights and experts' weights in which the information provided by each decision maker in expressed as the hybrid decision matrix where each of the elements is expressed by intuitionistic fuzzy number, interval-valued intuitionistic fuzzy number and linguistic labels. First, define a transformation function which can change multi-granularity linguistic variables to interval-valued intuitionistic fuzzy numbers. Then, ensure the unknown attributes' weights based on the support degrees, and next establish a model to ensure the weights of decision makers which considering the entropy and similarity of interval-valued intuitionistic fuzzy numbers. After transform hybrid decision matrices to interval-valued intuitionistic fuzzy matrices, we can aggregate these individual decision matrices by using IIFWA operation for ranking alternatives. Finally, an illustrative example for supplier selection is given to prove this method. [ABSTRACT FROM AUTHOR]

In order to explore the interaction between nitrocellulose (NC) and nitroglycerine (NG) of composite modified double-base (CMDB) propellants, the radius of gyration of NC molecules and radial distribution function for different atoms of NC and NC/NG blends were calculated by using molecular dynamics simulation( MD) . It was found that the radius of gyration of NC molecules was independent on the temperature, while the number of NG molecules increased greatly with temperature. Besides, according to the radial distribution function of the models, it was revealed that the H-bond could be formed between NG and NC molecules instead of H-bond in the individual NC molecule, which could decrease the interaction force inside NC molecules, thus increase the radius of gyration of NC. [ABSTRACT FROM AUTHOR]

Several most commonly used tools for road-surface milling-planing are introduced, and their structural difference and characteristics are analyzed to improve the quality of tools. The material composition, structure and property, brazing material and joint strength between tool head and tool body are studied by optical microscope (OM), scanning electron microscope (SEM), energy depressive spectroscopy (EDS) and microhardness tester, etc. Based on experimental results, some recommendations are presented as follows:the tool with fiat-bottomed and v-grooved welding structure is suited for milling-planing; the cemented carbide that the content of Cobalt is less than eight percent used as tool head material will give good results; the alloy steels, such as 5CrMnMo with high tempering temperature and tempering martensite, is selected as tool body; the tool head and tool body are jointed with Ni and Cr containing solder and high frequency induction heating brazing. [ABSTRACT FROM AUTHOR]

Service selection is a key step to transform a user's request into an optimal composite service plan. Most existing approaches are influenced by the number of tasks and candidate services and have shortcomings of long response time for large size candidate services and without considering the critical path. To solve above problems, a peer-to-peer (p2p) service overlay was built up to simulate distributed applications. Considering the composite construction and critical path, the end-to-end QoS constraint could be decomposed into local ones by using the management of service community, which facilitates parallel service selection. Experimental results demonstrate that the composite service plan could be built up with great reduced response time and the tradeoff to a near-optimal result. [ABSTRACT FROM AUTHOR]

This paper studied the soil physical properties, soil CO2, soil water and spring water chemistry in a mature forest and a shrub in Nongla of Guangxi, China, as well as the relationships between the chemistry of soil water and spring water, aimed to understand the karst effect of the soil water in Nongla epikarst dynamic system. Significant differences were observed in the soil bulk density and non-capillary porosity under forest and shrub, which affected soil water content. The fixed CO2 in soil water had a significant negative correlation with soil CO2, and the free CO2 in soil water was 0 mg · m-3 in the forest and 5.33 · 103 mg · m-3 in the shrub. In soil water and spring water, there was a negative correlation between pH and Ca2+, Mg2+, and Cl- concentrations, and a positive correlation between K+, Na+, and HCO3- concentrations and organic C content. After the eluviation of rain water, the ion concentrations in leached soil water increased greatly, and accordingly, its corrosion ability enhanced greatly. The karst process in forest environment was stable and intensive, while that in shrub environment was active but weak. [ABSTRACT FROM AUTHOR]

The numerical simulation based on shrink core model theory which describes the adsorption/desorption processes that occur in a compound adsorption refrigerator was performed. And the heat and mass transfer performance of the compound adsorbent SrCl2 impregnated activated carbon fiber (here the mass proportion of SrCl2 to activated carbon fiber is 4.27) was primarily analyzed, based on this model when the evaporate temperature is 5°C. The experimental analytical results conform to the theoretical simulation. [ABSTRACT FROM AUTHOR]

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A cross flow is applied on a missile, which has a great influence on the stage of out of tube, when a missile is launched from the concentric canister launcher during the movement of submarine. This leads to a series of launching safety and load problems. In order to obtain a higher degree of confidence of load characteristics out of tube both in time and spatial dimensions and use the less hypotheses, an unsteady simulation model which can solve the flow field and missile motion in consideration of the adapter elasticity and 3 DOF motion of missile is proposed and established by the first time. The effect of bubble elasticity on the load characteristics is analyzed. The motion parameters, load characteristics and adapter deformation during the launching of missile from launch tube are obtained. The results show that the oscillation resulting from the cross flow has an adverse effect on missile launching. [ABSTRACT FROM AUTHOR]

With the selection of Geldart B type magnetite powder as medium solids, we investigated the density distribution characteristic of the fluidized bed along the directions of bed heights and axial positions, by combining the experimental measurement and numerical simulation based on the Euler-Euler multi-phase model. The results indicate that the distribution range of bed densities along bed heights and axial positions are 1.95-2. 10 g/cm³ and 2.00-2. 10 g/cm³ respectively with the operating gas velocity of 1.50Umf ≤ U ≤ 2.20Umf, and the standard deviation both less than 0.20 g/cm³. The density stability of axial positions is better than the density stability along different bed heights. Therefore, we should pay close emphasis to maintain the density fluctuation along bed heights as least as possible, which aims to improve the density stability in the whole ADMFB. It shows good agreements of the experimental measurement and numerical simulation results. [ABSTRACT FROM AUTHOR]

This study aims to reveal the effects of the herb pair Astragali Radix-Salviae Miltiorrhizae Radix et Rhizoma(AR-SMRR) on phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR) pathway and autophagy in the lung tissue of the rat model of acute lung injury(ALI). Fifty adult male SD rats were randomized into sham, model, autophagy inhibition(intraperitoneal injection of chloroquine at 10 mg·kg~(-1)), autophagy induction(intraperitoneal injection of rapamycin at 15 mg·kg~(-1)), and AR-SMRR(5 g·kg~(-1), gavage) groups. The rats in the sham group received intratracheal instillation of normal saline, and those in other groups received intratracheal instillation of lipopolysaccharide(LPS, 5 mg·kg~(-1)) for the modeling of ALI. Seven days before the operation, the rats in the sham and model groups were administrated with normal saline, and those in other groups with corresponding drugs. Specimens were collected 24 h after modeling. The pathological changes of the lung tissue were observed under a light microscope. The lung wet/dry weight ratio and the lactate dehydrogenase(LDH) activity and total protein concentration in the bronchoalveolar lavage fluid(BALF) were measured. Western blot was employed to measure the protein levels of microtubule-associated protein 1-light chain 3(LC3), beclin-1, p62, PI3K, Akt, and mTOR. Compared with the sham group, the model group showed increased histopathological score of the lung tissue, lung wet/dry weight ratio, and LDH activity and protein concentration in BALF. Autophagy inhibition further increased these indicators compared with the model group, while autophagy induction and AR-SMRR lowered the levels. In addition, AR-SMRR up-regulated the protein levels of LC3-Ⅱ and beclin-1, down-regulated the expression of p62, and inhibited the expression of p-PI3K, p-Akt, and p-mTOR in the lung tissue of ALI rats. The findings suggest that AR-SMRR can alleviate the lung injury and edema in the rat model of ALI induced by LPS by enhancing autophagy via down-regulating PI3K/Akt/mTOR signaling pathway.

This paper aims to investigate the protective effect and mechanism of Astragalus membranaceus and Angelica sinensis before and after compatibility against triptolide(TP)-induced hepatotoxicity. The experiment was divided into a blank group, model group, Astragalus membranaceus group, Angelica sinensis group, and compatibility groups with Astragalus membranaceus/Angelica sinensis ratio of 1∶1, 2∶1, and 5∶1. TP-induced hepatotoxicity model was established, and corresponding drug intervention was carried out. The levels of alanine transaminase(ALT), aspartate transaminase(AST), and alkaline phosphatase(ALP) in serum were detected. Pathological injuries of livers were detected by hematoxylin-eosin(HE) staining. The levels of malondialdehyde(MDA), superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), and reduced glutathione(GSH) in the liver were measured. Wes-tern blot method was used to detect the expression of nuclear factor erythroid 2-related factor 2(Nrf2), Kelch-like ECH-associated protein 1(Keap1), peroxisome proliferator-activated receptor gamma, coactivator-1 alpha(PGC-1α), heme oxygenase-1(HO-1), and NAD(P)H quinone dehydrogenase 1(NQO1) in livers. Immunofluorescence was used to detect the expression of Nrf2 and PGC-1α in livers. The results indicated that Astragalus membranaceus/Angelica sinensis ratio of 2∶1 and 5∶1 could significantly reduce the levels of serum AST, ALT, and ALP, improve the pathological damage of liver tissue, increase the levels of GSH and GSH-Px, and reduce the content of MDA in liver tissue. Astragalus membranaceus/Angelica sinensis ratio of 1∶1 and 2∶1 could significantly improve the level of SOD. Astragalus membranaceus and Angelica sinensis before and after compatibility significantly increased the protein expression of HO-1 and NQO1, improved the protein expression of Nrf2 and PGC-1α, and decreased the protein expression of Keap1 in liver tissue. The above results confirmed that the compatibility of Astragalus membranaceus and Angelica sinensis had antioxidant effects by re-gulating Keap1/Nrf2/PGC-1α, and the Astragalus membranaceus/Angelica sinensis ratio of 2∶1 and 5∶1 had stronger antioxidant effect and significantly reduced TP-induced hepatoto-xicity.

Renal outer medullary potassium (ROMK) channel is an important K + excretion channel in the body, and K + secreted by the ROMK channels is most or all source of urinary potassium. Previous studies focused on the ROMK channels of thick ascending limb (TAL) and collecting duct (CD), while there were few studies on the involvement of ROMK channels of the late distal convoluted tubule (DCT2) in K + excretion. The purpose of the present study was mainly to record the ROMK channels current in renal DCT2 and observe the effect of high potassium diet on the ROMK channels by using single channel and whole-cell patch-clamp techniques. The results showed that a small conductance channel current with a conductance of 39 pS could be recorded in the apical membrane of renal DCT2, and it could be blocked by Tertiapin-Q (TPNQ), a ROMK channel inhibitor. The high potassium diet significantly increased the probability of ROMK channel current occurrence in the apical membrane of renal DCT2, and enhanced the activity of ROMK channel, compared to normal potassium diet (P < 0.01). Western blot results also demonstrated that the high potassium diet significantly up-regulated the protein expression levels of ROMK channels and epithelial sodium channel (ENaC), and down-regulated the protein expression level of Na + -Cl - cotransporter (NCC). Moreover, the high potassium diet significantly increased urinary potassium excretion. These results suggest that the high potassium diet may activate the ROMK channels in the apical membrane of renal DCT2 and increase the urinary potassium excretion by up-regulating the expression of renal ROMK channels.

Soil polluted by heavy metals (HMs) is an important environmental issue in China, and regional geological background is a vital factor that influences the enrichment of HMs in soils. Previous studies have shown that soils derived from black shales are commonly enriched in HMs and present high potential eco-environmental risks. However, few studies have investigated the HMs in different agricultural products, which inhibit the safe use of land and safe production of food crops in black shale regions. This study investigated the concentrations, pollution risks, and speciation of HMs in soils and agricultural products from a typical black shale region in Chongqing. The results showed that the study soils were enriched in Cd, Cr, Cu, Zn, and Se but not in Pb. Approximately 98.7% of total soils exceeded the risk screening values, and 47.3% of total soils exceeded the risk intervention values. Cd had the highest pollution level and potential ecological risks and was the primary pollutant in soils of the study area. Most of the Cd resided in ion-exchangeable fractions (40.6%), followed by residual fractions (19.1%) and weak organic matter combined fractions (16.6%), whereas Cr, Cu, Pb, Se, and Zn were dominated by residual fractions. Additionally, organic combined fractions contributed to Se and Cu, and Fe-Mn oxide combined fractions contributed to Pb. These results indicated that Cd had higher mobility and availability than those of other metals. The agricultural products presented a weak ability to accumulate HMs. Approximately 18.7% of the collected samples with Cd exceeded the safety limit, but the enrichment factor was relatively low, indicating low pollution risks of the heavy metals. The findings of this study could provide guidelines for safe use of land and safe production of food crops in black shale regions with high geological background.