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The first prerequisite for obtaining correct information from an X-ray diffraction pattern is to accurately remove the background. The most commonly used method in experiments is direct subtraction, which ignores the absorption of the sample and other interactions within the sample such as the photoelectric effect and the counting of photons produced by Compton scattering. The "rolling ball" algorithm and the use of software such as Jade deduction background as well as other deduction methods also have their own limitations. Monte Carlo simulation can identify and count the particles, so it is very important to use it for quantitative analysis of XRD background. In this study, the atomic Form Factor of each element in the air was calculated by the Baró fitting formula and the molecular Form Factor was given by the Debye formula and compared with the calculation results of the independent atomic model. Geant4 was used to simulate XRD for crystalline substances such as bone and nylon and amorphous substances such as water, and the background and real signals were effectively separated in the results, then the XRD background was quantitatively analyzed on this basis. The results show that there is a huge difference in counting between the independent atomic model and Debye's formula,and the Debye method produces more scattered particles. XRD background comes from the air scattering and other types of interactions between photons and matter in the sample, the former contributing the most at small angles, the proportion decreases from 100% to less than 40% with the increase of the scattering angle, and the proportion of the latter increases from 0 to more than 60% with the scattering angle. The results indirectly illustrate the inaccuracy of the background subtraction methods in the experiment. Such as the direct subtraction method not only ignores the absorption of X-ray by the sample, but also ignores the background count caused by other interactions of X-ray photons in the sample. To accurately remove the background, all the counts of background mentioned above must be considered. The Monte Carlo method was used to simulate the XRD background, and the simulation was closely connected with the practice. The same XRD background pattern can be obtained by constructing the same geometric model as the experiment, setting the same physical parameters as the experiment, and using the same sample Form Factor as the experiment. Applying the simulation results to actual experiments may become a more accurate method of background deduction.

In deep-sea operations, tethers play a vital role in providing energy supply and information transmission for remotely operated vehicles (ROVs). To further refine the collect and release planning of the tether and to regulate ROVs' underwater range of motion, this study proposes a novel tether management system powered by permanent magnet synchronous motors. The surface-underwater control systems and their logical control methods have been thoughtfully designed to meet the tether's working requirements. The electric tether management system comprises components such as a drum, sheave, permanent magnet motor, and respective drivers, presenting a more compact structure than traditional hydraulic-powered tether management systems. Through a sprocket, the system ensures synchronicity between the drum and the spooler for a corrugated motion, facilitating correct tether winding around the drum. By analytically considering the torque and speed statuses of the drum and sheave across typical tether pick-up and pay-out modes, this study validates the effectiveness of the electric tether management system's control and logic. The results indicate that the electric tether management system can efficiently collaborate with the ROV to perform underwater operations, thereby contributing to stable and efficient ROV system operation.

Objective To analyze the expression of SEC61G in oral squamous cell carcinoma (OSCC) tissues and cell lines and determine its correlations with the clinicopathological features and prognosis of patients with OSCC. Methods The expression of SEC61G in OSCC tissues and its diagnostic and prognostic value were detected in the TCGA database. The expression levels of SEC61G in paraffin-embedded OSCC tissues and adjacent normal tissue specimens of 64 patients with OSCC were detected by immunohistochemistry. The correlation of SEC61G expression in OSCC tissues with the clinicopathological features was analyzed. Kaplan-Meier survival curve analysis showed that the expression of SEC61G correlated with the overall survival time of patients with OSCC. Cox regression analysis was used to analyze prognostic influence factors. Results The expression of SEC61G in OSCC tissues was significantly higher than that in para-carcinoma tissues (P < 0.05), consistent with the results of the TCGA database analysis, and its expression was closely related to N stage and clinical stage (P < 0.05). The overall survival of patients with OSCC in the group with low SEC61G expression was significantly higher than that in the high SEC61G expression group (P < 0.05). N stage and SEC61G expression were the prognostic influence factors for patients with OSCC (P < 0.05). SEC61G expression was an independent predictor of the prognosis of patients with OSCC (P < 0.05, AUC=0.923). Conclusion SEC61G is highly expressed in OSCC tissues and associated with N stage and clinical stage. Its high expression is associated with poor prognosis of patients. It may be a diagnostic biomarker for OSCC.

X-ray tube can easily produce X-ray, which is widely used in industry, archaeology and medicine. X-ray tubes use the interaction between high-speed electrons and anodic target atoms to generate X-rays, including discrete characteristic X-rays and continuous bremsstrahlung spectrum. Their spectral distribution is an important parameter index, which is the basis of subsequent applications. The spectral distribution can be obtained by actual measurement, Monte Carlo simulation and analytical calculation. Here, the analytical calculation of bremsstrahlung spectrum was mainly studied. Analytical calculation is to quickly calculate the bremsstrahlung spectrum produced by X-ray tube using known parameters. The key to its accuracy is the depth distribution of electrons in the anode target. By analyzing the depth distribution of electrons in the anode target, an analytical calculation model for the bremsstrahlung spectrum of electrons with incident energy from 10 to 50 keV in the copper target was established. Due to the elastic and inelastic interactions, the electron transport process in the target is very complex, and it is difficult to obtain the electron depth distribution by experimental or theoretical analysis. Monte Carlo simulation software Geant4 was used to simulate the interaction between the electron and copper target with incident energy of 10, 20, 30, 40 and 50 keV. The count, energy distribution and angle distribution of the electron at different penetration depths were obtained. The empirical formulas of electron depth distribution and path length correction coefficient of 10.50 keV electrons in copper target were obtained by fitting the simulated data. Since the penetration depth was scaled by using the continuous slowing down approximation range RCSDA, the parameters of the fitted empirical formula were approximately independent of the incident energy of electrons in this energy segment. The calculated results of the empirical formula for the electron depth distribution are in good agreement with the data of the electron depth distribution simulated by Geant4, which can accurately represent the electron depth distribution and the correction coefficient of path length. Combining the empirical formulas of electron depth distribution and path length correction coefficient with the corresponding bremsstrahlung cross-section data, an analytical calculation model of the bremsstrahlung spectrum of the thick target reflection type X-ray tube was established. Compared with Monte Carlo simulation results, the analytical calculation model has high accuracy and is in good agreement with the simulation results. When the electron incident energy is 15, 25, 35 and 45 keV, the spectral errors are 0.036 6, 0.041 7, 0.040 8 and 0.038 9, respectively. Compared with Monte Carlo simulation of X-ray tube bremsstrahlung spectrum, the analytical calculation speed is faster and can achieve high accuracy, which can be used in the need of fast calculation of X-ray tube bremsstrahlung spectrum.

Objective To investigate effects of IL-6 trans-signaling on immuno-inflammatory regulation in cecum ligation and puncture (CLP)-induced mice with sepsis. Methods Eighty mice were divided randomly into four groups: sham group (n=15), CLP group (n=30), CLP+sgp130Fc group (n=20) and sgp130Fc group (n=15). Sgp130Fc 0.5 mg/kg was injected intraperitoneally one hour after CLP in the CLP+sgp130Fc group and sgp130Fc group. Body weight and survival rate of mice were monitored daily during the research period (10 days). At 24 hrs after CLP, IL-6,IL-10, MCP-1 and TNFα were detected by ELISA; Peripheral blood leukocytes were separated and lymphocyte subgroups were sorted with the flow cytometry. Results Compared with sham group, the survival rate and body weight decreased significantly(P＜0.05). At 24 hrs after CLP, the expression of IL-6, IL-10, MCP-1 and TNFα increased significantly(P＜0.05). Lower level of the CD3+ CD4+ T cell and CD45+ CD19+ B cell but higher level of the CD3+ CD8+ T cell in the CLP group were found (P＜0.05). Compared with the CLP group, the survival rate was increased significantly(P＜0.05). At 24 hrs after CLP, the expression of IL-6, IL-10, MCP-1 and TNFα decreased significantly, and higher level of CD3+ CD4+ T cell and CD45+ CD19+ B cell but lower level of CD3+ CD8+ T cell in the CLP+ sgp130Fc group(P＜0.05) were recorded. Conclusions Inhibition of IL-6 trans-signaling can reduce mortality of mice with sepsis, which is potentially related to the regulation of early peripheral blood lymphocyte subgroups and inhibition of inflammatory responses.

The Ounan depression is a favorable structural unit for the Carboniferous hydrocarbon migration and accumulation, which demonstrates certain exploration potential. However, the organic matter enrichment mechanism is still unclear, which results in the absence of effective guidance for predicting the distribution of high-quality source rocks and restricts the process of oil and gas exploration. Based on geochemical analysis and XRD, SEM and other tests, the main factors influencing the enrichment of organic matters in Carboniferous source rocks have been identified through a comprehensive investigation into the aspects such as mineral composition, organic matter abundance, kerogen type, thermal evolution degree, formation environment, and the relationship between TOC and primary minerals. The results reveal that shales and carbonate source rocks have been developed in the Carboniferous, a large quantity at poor-medium level and a few at good or above level. They were deposited in the environment of intercontinental shelf with saline-water, arid-hot climate and weak oxidation and reduction. The dispersed organic matters are composed of mixed marine and terrestrial origins, which are overall in a "maturity-high maturity stage". The Carboniferous clastic source rocks are mainly residual type Ⅲ kerogen, but the extracted chloroform bitumen "A" is mainly derived from type Ⅱ kerogen.TOC values increase with the growing of quartz minerals because the high-abundance source rocks are rich in siliceous biological fossils. The SiO2 in the high-SiO2 source rocks has been identified as biogenic, suggesting that the participation of siliceous organisms in the Carboniferous cause the enrichment of marine organic matters and greatly improve the primary productivity of the sediments. This study provide the basis for predicting the distribution of Carboniferous high-quality source rocks and the deployment of oil and gas resources in the study area.

BackgroundChina has seen a significantly increased prevalence of chronic obstructive pulmonary disease (COPD) recently. But primary care institutions, the main "battlefield" for containing COPD, have shown relatively weak capabilities for the diagnosis and treatment of disease. As there are relatively few large-scale investigations and studies on medicines and diagnostic devices for COPD in primary care, we conducted this study to further understand the weaknesses of current COPD containment in primary care, by which the gap in related research may be made up.ObjectiveTo understand the allocation and availability rate of essential medicines for COPD, and availability rate of spirometer as well as the implementation of pulmonary function tests in primary care.MethodsFrom February to March 2021, a multi-stage cluster sampling was adopted to select 8 176 community (township) health centers from 31 provinces of China to attend a survey. The rates of availability and allocation of each of the 16 essential medicines for COPD in the 2018 National Essential Medicines List were calculated to estimate the categories and number of these medicines in primary care institutions. The rate of availability of spirometer in these institutions was estimated. And the rate of implementation of pulmonary function tests in these institutions was estimated.ResultsAltogether, 7 458 (91.22%) institutions who gave effective responses to the survey were included for analysis, including 5 901 (79.12%) township health centers, and 1 557 (20.88%) community health centers. Among the 16 essential medicines for COPD, less than 8 were available in 6 538 (87.66%) institutions, at least 1 inhaled antiasthmatic medicines were available in 4 992 (66.00%) institutions, and long-acting inhaled antiasthmatic medicines were available in 814 (10.91%) institutions. The average availability rate of 16 essential medicines for COPD was 33.30%. The highest ranked three medicines in terms of availability rate were ambroxol〔85.28% (6 360/7 458) 〕, aminophylline〔81.17% (6 054/7 458) 〕 and compound licorice〔74.48% (5 555/7 458) 〕. And the relatively low-ranked three were fluticasone propionate 〔4.89% (365/7 458) 〕, tiotropium bromide〔6.25% (466/7 458) 〕, budesonide forterol〔8.61% (642/7 458) 〕. The average availability rate of 6 inhaled antiasthmatic medicines in community health centers was 28.31%, and that in township health centers was 4.81%. The average availability rate of 2 long-acting inhaled antiasthmatic medicines in community health centers was 16.18%, and that in township health centers was 5.12%. The average availability rate of spirometers in primary care institutions was 8.94% (667/7 458) . The average availability rate of spirometers in community health centers was higher than that of township health centers〔18.56% (289/1 557) vs 6.41% (378/5 901) , P

To determine the snow melting effect and the evaluation index of DTC phase change material (PCM) in asphalt pavement, the snow melting effect of phase change asphalt mixture under low temperatures was studied and analyzed by designing indoor and outdoor snow melting tests. The asphalt mixture specimens without phase change materials was taken as the control group. The results show that the phase change material in asphalt mixture has a noticeable thermoregulation effect, and the larger the dosage, the greater the snow melting effect. When the phase change material dosage is 0. 5% and the snow thickness are 1. 5 cm and 3. 0 cm, respectively, the phase change asphalt mixture snow melting rate increased by 19. 0% and 16. 0% compared with ordinary asphalt mixture. Based on the indoor and outdoor snow melting tests, the snow thickness change rate (Δh) and residual snow coverage (RSC) were proposed as the comprehensive evaluation indexes of the snow melting effect of phase change asphalt mixture. [ABSTRACT FROM AUTHOR]

In the process of missile design, the aerodynamic characteristics of missile as an important factor directly affect the dynamic quality of missile flight. In the case of severe nonlinearity of aerodynamic characteristics in subsonic and transonic regions, the aerodynamic calculation accuracy provided by engineering estimation and CFD numerical calculation method is limited, which leads to low identification accuracy of rudder efficiency characteristics, so it is necessary to calculate aerodynamic parameters accurately by wind tunnel test method to determine the rudder efficiency of missiles. The influence of Mach number of missile flight on aerodynamic characteristics of missile in subsonic and transonic speed is studied by means of wind tunnel test method, and the driving efficiency of rudder is analyzed according to aerodynamic characteristics. The results show that, with the increase of Mach number, the aerodynamic characteristics of the missile are basically the same as at subsonic speed; the pitch rudder efficiency of the missile is increased first and then decreased, while the roll rudder efficiency is decreased first and then increased at subtransonic speed.

Objective To study the effects of hedysarum polybotys saccharides (HPS) and selenizated hedysarum polybotys saccharides (SE-HPS) on the oral squamous cancer cell line SCC25. Methods Different concentrations (0, 10, 25, 50, 100, 200, 400 μg/ml) of HPS and SE-HPS were added to SCC25 cells in the logarithmic growth stage. Cell proliferation was detected by the CCK-8 method, apoptosis was detected by flow cytometry, and apoptosis-related indexes were observed by RT-qPCR and Western blotting. Results The concentrations of HPS and SE-HPS inhibited the proliferation of SCC25 cells. The inhibitory effect of 50 μg/mL HPS and SE-HPS on the proliferation of SCC25 cells was the strongest and was time-dependent. The inhibition effect significantly increased within 48 h, and the effect was achieved after 48 h. At the plateau stage, SE-HPS inhibited the proliferation of SCC25 cells more strongly than HPS (P < 0.05). The results of flow cytometry showed that 50 μg/mL HPS and SE-HPS acted on SCC25 cells for 48 h, and the apoptotic rates were 25.8% and 30.8% respectively. Compared with the control group (0 μg/mL HPS and SE-HPS), the difference was statistically significant (P < 0.05). RT-qPCR and Western blotting showed that 50 μg/mL HPS and SE-HPS acted on SCC25 cells for 48 h, and the mRNA and protein expression levels of the apoptosis gene Fas/FasL were upregulated. The difference was statistically significant (P < 0.05). Conclusion Both HPS and SE-HPS can inhibit the proliferation of SCC25 oral cancer cells, but SE-HPS is superior to HPS and can induce apoptosis through the Fas/Fasl pathway.

[Objective] The present study investigated the effects of heat stress on physiological traits n leaves of different rice varieties at seedling stage and the relationship with heat resistance to provide basis for breeding heat tolerant rice varieties. [Method] Eight indica and eight japonica rice varieties were treated at conditions of control (28 °C/22 °C, day (07 : 00 - 19 : 00)/night ( 19 : 00 - 07 : 00 ), CK ) and heat tress (42 °C/35 °C, day(07 : 00-19 : 00)/night (19 : 00 -07 : 00), HS) at seedling stage. All varieties were classified to different heat tolerant degrees (highly tolerant, HT; moderately tolerant, MT; sensitive, S and mostly sensitive, MS) according to the survival rates under heat stress. The effects of heat stress on relative water content, chlorophyll content, reactive oxygen species (ROS) accumulation, membrane injury, antioxidant enzyme activity, osmotic adjustment substances and endogenous phytohormone content in leaves were also evaluated. [Result] Dongdao-4 (C10), Xiangliangyou-2 (C8), Huanghuazhan (C1) and Changbai-9 (C16) were highly tolerant rice varieties under heat stress condition with high seedlings survival rates. Xiangliangyou900 (C6), Taiyou390 (C7), Zhenghan-6 (C12), Wuyungeng21 (C11), Yuewangsimiao (C4) and Jigeng-515 (C13) were mostly sensitive varieties. Compared with CK, HS decreased contents of water, chlorophyll and endogenous 1AA, Z+ZR and GA3 contents in rice leaf, while increased ROS accumulation, membrane injury (relative electrical conductivity and MDA content), antioxidant enzyme activities (SOD, POD, CAT and APX) and contents of osmotic adjustment substances (proline and soluble sugar) and en-dogenous ABA. The relative water content, chlorophyll content, SOD, POD and CAT activities, and endogenous ABA content in heat tolerant rice varieties were significantly higher than those in heat sensitive varieties, while ROS content, relative electrical conductivity and MDA content were significantly lower. There was no significant difference in APX activity, and contents of osmotic adjustment substances and endogenous IAA, Z + ZR and GA3 between heat tolerant and sensitive varieties. The ROS accumulation, antioxidant enzyme activity, membrane injury degree and endogenous ABA content were significantly correlated to survival rates of rice varieties, which could be used for screening heat tolerant varieties. [Conclusion] Heat stress induced over accumulation of ROS in leaves and resulted oxidative stress were main reason for leaf withering. Improving antioxidant defense capability and endogenous ABA signaling was an important path-way in rice for resisting heat stress, and it can be used as an important breeding strategy for heat tolerant rice resources. [ABSTRACT FROM AUTHOR]

To reveal the effect of different land use types on soil cellulase activity (SCA) and soil fertility factors, and clarify the relationship between soil chemical factors and SCA. In Hailun City, Heilongjiang Province, the soils from dry land and forest land were as the research object, and path analysis method was used to clarify the positive and negative effects of soil chemical factors on SCA. The results showed that the contents of organic carbon, total nitrogen, total phosphorus, water content and SCA of forest land were significantly higher than those of dry land, while the pH of dry land was significantly higher than that of forest land. The correlation analysis showed that there was significant negative correlations between SCA and organic carbon, total nitrogen in dry land, and there was extremely significantly positive correlation between SCA and organic carbon, water content, and significant positive correlation between SCA and TN in forest land. Path analysis showed that pH, total nitrogen and water content were important factors that had significant and direct effects on SCA in dry land, while organic carbon and total nitrogen had indirect negative effects on SCA. Organic carbon and total nitrogen were the main controlling factors of SCA in forest land. The soil fertility factors and SCA were obviously difference between dry land and forest land. The nutrient level and SCA of dry land soil were lower than those of forest land, which indicated that there was long-term and intensive human use of dry land in this region, leading to the degradation of the nutrient status of dry land and the reduction of water content. [ABSTRACT FROM AUTHOR]

The terahertz(THz) wave is located in the transition region of photonics to electronics, and has important application prospects in high-speed broadband communication, radar, imaging and other fields. However, the devices currently used for dynamic regulation of THz waves are still lacking, which limits the development of THz technology to some extent. VO2 has an unique metal-insulator phase change characteristic, and the phase change process can be applied to dynamically regulate THz wave transmission. It is also a recent research hotspot to explore the combination of metamaterials and VO2 to prepare efficient, dynamic and flexible terahertz functional devices. In this paper, the phase transition characteristics of VO2 are briefly described, and the effects of microstructure and chemical composition on phase transition characteristics are analyzed. The research progress of VO2 film in THz band regulation performance is reviewed systematically, and the different combinations of VO2 and metamaterials are summarized. In the application of THz wave dynamic regulation, the development prospects and challenges of THz wave regulation function devices based on VO2 phase transition characteristics are prospected.

C/C-SiC composites were prepared by the combined process of chemical vapor infiltration (CVI) and gaseous silicon infiltration (GSI) using C/C green body with the density of 1.0g/cm3. Effect of CVI C/C-SiC intermediate composites' density on the phase composition, microstructure and mechanical properties of CVI-GSI C/C-SiC composites was studied. The results show that as the CVI C/C-SiC intermediate composites' density increases, the residual C content increases and residual Si content decreases in the CVI-GSI C/C-SiC composites, the SiC content increases first and then decreases, and the density of CVI-GSI C/C-SiC composites increases first and then decreases; as the CVI C/C-SiC in termediate composites' density is increased from 1.27g/cm3 to 1.63g/cm3, the mechanical properties of CVI-GSI C/C-SiC composites increase at first, which then decrease with the further increasing of CVI-C/C-SiC composites' density. Specifically, when the CVI C/C-SiC composites density is 1.42g/cm3, the prepared CVI-GSI C/C-SiC composites has the best mechanical properties, with flexure strength, flexure modulus and fracture toughness of 247.50MPa, 25.63GPa and 10.08MPa·m1/2, respectively.

Superhydrophobicity and superhydrophilicity are extreme properties of solid surface governed by surface morphology and surface chemistry. Switching between superhydrophobicity and superhydrophilicity can be achieved by applying external stimuli and exchanging counterions due to the change in surface morphology and/or surface chemistry. This review mainly gives a concise overview of switchable wettability of surface. Through applying external stimuli such as light, temperature, pH value, solvent, electric potential and exchanging of counterions, the wettability of surface can switch between superhydrophobicity and superhydrophilicity. The material with asymmetric wettability exhibits some novel abilities such as directional liquid transport. Finally, the advances of surface with switchable wettability are prospected. By controlling the micro-nano structure and chemical composition, the switch between superhydrophobicity and superhydrophilicity can be realized on various surfaces.

Aiming at diseases of high-speed railway such as track structure void, the effectiveness of real-time monitoring using fiber-optic vibration measurement technology was studied through numerical simulation and field test. A section of damaged line was selected, and the distributed optical fiber vibration monitoring system based on the principle of Φ-OTDR was adopted. The vibration measuring optical fiber was laid on the surface of the track plate in the middle of the two rails, and then the optical fiber was drawn to the monitoring base station outside the track. The vibration data before and after the repair of the disease were collected and recorded by the DOVS optical fiber vibration analyzer, and the under-rail structure was detected in detail by the impact image method. The research shows that the influence of the void disease of the under-rail structure on vibration is divided into vibration excitation and vibration amplification. The near vibration source may cause resonance, and its amplification effect is obvious compared with that of the far vibration source, which can reach 2-3 times of the original amplitude. [ABSTRACT FROM AUTHOR]

This paper intends to provide an analytical framework to interpret the dynamic nexus between China and the world order from the perspective of the neo-Gramscian international relations school. It supposes that the post-war world order is mainly shaped by and reflected in the architecture of international/global governance. This supposition is largely built on the conceptual nexus between global governance, hegemony, and world order. Then, through the lens of global governance, the paper contends that the post-war historical dynamics between China and the world order can be divided into three periods: first the period of hostility and rejection (1949-1971), second the period of acceptance and integration (1971-2008), and third the period of leadership and contribution (2008 up to now). On the basis of such chronology, the paper attempts to deliver a historical and holistic interpretation of China’s changing role in the post-war world order. By distinguishing the roles China played and is playing in different historical periods, and by elaborating this dynamic historical process through a holistic view, this paper concludes that China is currently serving as a proactive rule-shaper rather than a disruptive revisionist or a stubborn vindicator of the existing world order.

This study quantitatively characterized the positive and negative centroplasm effects of superabsorbent polymer (SAP) aggregate with different particle sizes (6 ~20 mm) by testing the compressive strength of concrete with single SAP or expanded polystyrene (EPS) aggregate, drawing on the centroplasm hypothesis. The results show that the water release of SAP aggregate exhibits a positive centroplasm effect on cement mortar due to the interfacial enhancement and a negative centroplasm effect due to pore formation. The empirical formula of negative centroplasm effects caused by pores induced by SAP aggregate is proposed. With the increase of SAP aggregate size, its negative centroplasm effect increases, while its positive centroplasm effect increases first and then decreases. The concept of "critical size" of SAP aggregate in mortar with different water-cement ratios is proposed. It is related to the water-cement ratio and the curing age of mortar. [ABSTRACT FROM AUTHOR]

The quality and safety of hay is of great significance to the stable development of animal husbandry. However, the harvest and mowing period of forage is often in rainy season, hay is prone to mildew during storage, which poses potential safety hazards to livestock and humans. As one of the natural anti-mildew agents, plant essential oil is widely used in forage storage. Compared with chemical anti-mildew agent, plant essential oil is more safe and effective, and pollution-free to the environment, so it has great potential for development. The article reviews the conditions and hazards of forage mildew, the types of plant essential oils, antibacterial properties and the application in forage mildew control, in order to provide reference for the further application of plant essential oils in hay processing and storage. [ABSTRACT FROM AUTHOR]

This paper firstly reviews the history and trends in development of spaceborne Synthetic Aperture Radar (SAR) satellite technology in American and European countries. Besides, the basic information of the launched satellites and the future satellite plans are introduced. Then this paper summaries and assorts the imaging algorithm of spaceborn SAR satellite and analyzes the advantages and disadvantages of each algorithm. Moreover, the scope and the application status of each algorithm are presented. And then the paper elaborates trends of SAR imaging algorithm, which mainly introduces the algorithms based on compressive sensing theory and new image modes, and the results of simulation are also illustrated. At last, the paper summaries the development direction of spaceborne SAR imaging algorithm.

The boundary between the Triassic and Jurassic periods is a key moment in Earth history, which is distinguished by one of the five biggest mass extinctions, Pangea progressively breaking apart with the opening of the central Atlantic Ocean, eruption of Central Atlantic Magma Province, and a dramatic increase in the CO2 concentration. However, the major occurrence of terrestrial sediments in China has been difficult to bio-stratigraphically correlate with the Global Stratotype Section and Point (GSSP) defined in marine strata from the Triassic-Jurassic boundary (TJB). Two new <5I3C wood stratigraphic curves in the Kuqa River section were generated from two independent samplings, focusing on the materials within the charcoal and coalified fossil wood and representing the synchronous evolution of <5I3C in atmospheric CO2. The consistency of the two results proves the repeatability of this study, verifying the method of carbon-isotope stratigraphic sampling. The terrestrial Kuqa River section in the Tarim Basin is well correlated with the TJB of GSSP in Austria and other typical global sections, as constrained by the biostratigraphy of sporo-pollen assemblages and mega-plant fossils. The end-Triassic mass extinction (ETE) beginning horizon and synchronous TJB of GSSP are located near the bottom of Beds 38 and 41, respectively. The obvious negative carbon isotope excursion took place at the of the ETE beginning horizon and TJB. The significant fluctuations of carbon-isotope records in both marine and terrestrial strata across the ETE and TJB have been discovered globally, suggesting a global perturbation of carbon reservoirs within Earth surface cycles during this period. [ABSTRACT FROM AUTHOR]

There were multiple episodes of magmatism in the Southern Da Hinggan Mountains during the Late Jurassic to Early Cretaceous, and an in-depth study of the petrogenesis and evolutionary process is of great geological significance to reveal the Mesozoic geodynamic background and mineralization. In this paper, LA-ICP-MS zircon U-Pb dating and whole-rock geochemistry for medium-grained adamellite, fine-grained adamellite and granite peg-matite in Hailiute area were carried out. The zircon 206Pb/238U weighted average ages of the medium-grained adam-ellite, fine-grained adamellite and granite pegmatite are 142.0 ± 0.7 Ma, 141.2 ± 1.1 Ma and 139.7 ± 2.4 Ma respectively, belonging to the Early Cretaceous. They have high SiO2 and total alkali contents, and their A/CNK value is 1.01 ~ 1.18, with an average value of 1.09, which is weak peraluminous. They are characterized by enrichment of large ion lithophile elements such as Rb, Th and K and depletion of high field strength elements including Ba, Sr, P and Ti, with extremely negative Eu anomalies (δEu = 0.012~0.040). The Zr+Nb+Ce+Y value of them is between 38. 25x10-6 and 258. 2x10-6, less than 350x10-6. The zircon saturation temperature of them is 723X1 to 778X1. The primary muscovite and alkaline-mafic minerals Eire not found among them. The magma experienced the fractional crystallization of plagioclase and K-feldspar during its evolution. The Zr/Hf, La/Ta and La/Nb of them are lower than the range of normal granite, however Nb/Ta and Y/Ho of them are in the area of normal granite. The parameters of tetrad effect of rare earth element (TE1,3) of them is between 1.18 and 1.34, greater than 1.1. In conclusion, the Hailiute granite belongs to early Cretaceous highly differentiated I-type granite. It has weak interaction between melt and fluid in the process of crystallization differentiation, which can promote the formation of tungsten, tin and rare metals minerals. [ABSTRACT FROM AUTHOR]

This paper reviewed the research progress in the preparation of polymer/graphene composites, and two emerging preparation methods were introduced emphatically. The structural and performance design of polymer/graphene functional composites were described in detail, and their future development direction was prospected. This review provided an important reference for the research and development of advanced polymer/graphene composites, promoting the comprehensive research and industrial applications of graphene. [ABSTRACT FROM AUTHOR]

Aiming at the weak early fault characteristics of rolling bearings which were difficult to extract under interference of noise and harmonics, a fault diagnosis method was proposed based on DTD transform and SCS. Firstly, original signals were transformed by DTD transform, and the diagonal series of DTD spectrum was used as reconstructed signals. Secondly, the reconstructed signals were handled by SCS method to suppress the interference of noises and low-frequency harmonics. Finally, denoised signal were analyzed by envelope spectrum to extract fault characteristic frequency, judge fault type, and realize fault diagnosis. Analyzed results of simulation signals, experimental signals, and engineering signals show that the proposed method may effectively extract weak fault characteristics in the early fault signals of rolling bearings and accurately judge the fault type. [ABSTRACT FROM AUTHOR]

Using phosphogypsum, lime, and cement to stabilize the roadbed soil, the lime-phosphorus stabilized soil and cement phosphogypsum stabilized soil were respectively subjected to CBR test, compressive elastic modulus test, and 7 d unconfined compressive strength test to determine the recommended mix ratio of phosphogypsum comprehensive stabilized roadbed soil. The results show that the CBR, compressive elastic modulus and unconfined compressive strength of lime-phosphorus stabilized soil and cement-phosphorus stabilized soil increase with the increase of the dosage of phosphogypsum; the lime dosage in lime-phosphorus stabilized soil is 5%~7%,and when the proportion of lime-phosphorus gypsum is 1:1.5,the cement dosage in cement-phosphorus stabilized soil is 4%~ 6%,and when the ratio of cement phosphogypsum is 1:2,the mechanics of mixture performance and economy are the best. [ABSTRACT FROM AUTHOR]

Leaf orientation value is a comprehensive index reflecting the two characteristics of "straight" and "vertical" of leaves. The varieties with high leaf orientation value have straight and not curved leaves, and small angle, which are conducive to the wind ventilation and light transmission for maize population. When the planting density is high, it is easier to obtain high yield than the expanded plant-type. It is of great significance for molecular design breeding of ideal plant type to clarify the genetic basis of leaf orientation value. In this study, 285 diverse lines genotyped by the MaizeSNP50 chip were evaluated for leaf orientation in 2017 and 2018. The genome-wide association analysis (GWAS) were used to identified the SNPs, which were significant association with leaf orientation values. The analysis of variance showed that the significant variations were observed for leaf orientation value of different inbred lines (P < 0.01). In the selection of the optimal model, it was found that the Q + K model was the most suitable for the leaf orientation association analysis in this study. A total of 15 loci (P < 4.05E-5) were detected by GWAS, including 27 SNPs, explaining 5.54%-8.73% of phenotypic variation, and 15 candidate genes were mined in two years. Among them, site 2 in 1.07 bin was an important site found in this study, and its candidate gene might be Zm00001d032050 encoding cyclin dependent protein kinase, which needed to be further confirmed by map-based cloning. [ABSTRACT FROM AUTHOR]

To improve the recognition and positioning accuracy of road intersection extraction on electronic map, an automatic extraction method of road intersection on electronic map based on neighborhood features was proposed. Firstly, the road information of electronic map was extracted by object-oriented classification, and the road network was constructed after the road information is connected and refined by morphological algorithm. Then, the features of eight neighborhood foreground points of the road intersections were taken as the judgment rules to traverse the road network and extract the initial road intersections. Finally, the straight line fitted by the least square method was used to correct the positions deviation of the intersections to obtain the ac-curate locations of the intersections. The experimental results show that the recognition and positioning accuracy are improved, which can effectively extract the road intersections of the electronic map. [ABSTRACT FROM AUTHOR]

Urban village reconstruction has improved the living environment of the aborigines and effectively promoted urban economy. However, the negative impact between the aboriginal occupation and residence is widespread, and it has attracted broad attention of the public and academia. Taking urban villages of Taiyuan as an example, this paper randomly surveys 1, 000 aborigines in urban village and constructs a binary logistic regression model to identify and analyze the key influencing factors leading to the negative impact on the aboriginal occupational relationship after the reconstruction of urban villages. Results show that in urban village reconstruction, eight factors including household labor force, education level, occupation type, monthly income, resettlement mode, resettlement satisfaction, traffic satisfaction, and job changes have a significant impact on changes in occupational relations. Moreover, compared with the people with high income, low-income and low-education aborigines represent a more obvious change on the occupation and residence relationship. This paper provides corresponding policy recommendations and suggestions for making resettlement plan of the urban village reconstruction. [ABSTRACT FROM AUTHOR]

In order to solve the problems of large noise and defective fracture surface in the 3D data model of Terracotta blocks, a fracture surface matching method based on geometric features of Terracotta was proposed. Firstly, the fracture surfaces were segmented and recognized from the outer surface of Terracotta blocks; Secondly, the concave and convex feature regions of the fracture surface were extracted, and the coarse matching of blocks was completed according to the similarity of feature regions; Lastly, the geometry features including curvature, surface normals and point cloud density were calculated, and the fine matching of blocks was completed using the improved iterative closest point (ICP) based on the geometry features, thus the Terracotta blocks were matching accurately. A great number of Terracotta blocks were used to validate the proposed matching method. The results show that the proposed matching method can complete the Terracotta blocks matching. Especially the proposed fine matching algorithm, compared with ICP and MICP, the matching accuracy can increase by about 40% and 10% respectively, and the time consuming can decrease by 50% and 25 % respectively. So the matching method based on geometric features is an effective Terracotta blocks matching method. [ABSTRACT FROM AUTHOR]

A modified NDLT-HPM (MNDLT-HPM for short) was proposed through introduction of a parameter into the NDLT-HPM (nonlinearities distribution Laplace transform-homotopy perturbation method). This parameter makes the solving process for the nonlinear differential equations more flexible and is able to adjust and control the convergence region of the series solution, meanwhile overcomes the limitations of the NDLT-HPM that the series solution may be non-convergent when embedded parameter p equals 1. The present algorithm gives series solutions which converge well to the corresponding exact ones, thus obtaining sufficiently accurate approximate analytical solutions. 2 numerical examples show the advantage and accuracy of this method. [ABSTRACT FROM AUTHOR]

The grafting of the Internet of things to traditional labs has a brûlant future, it wiil enhance the intelligent level of supervision. Combined with the reality of the lab's improvement of our university, the paper introduces the constriction scheme and technical details oo the system including soofware and hardware, and the improvement in the aspects of "safety, energy saving, efficiency, comfort". II has been proved by practice that this management system has obtained the expected effect, it raise s the level of lab management, reduces the workload of the staffs, saves e nergy and prooects environment, and improves security and environment of lab teaching. [ABSTRACT FROM AUTHOR]

Biochar is a solid material that is produced from biomass pyrolysis in oxygen-limited atmosphere at relatively low temperatures. Therefore, the conversion of biosolids (e.g. agricultural waste, invasive species, municipal sewage sludge, etc) into biochar could provide a useful way to achieve resource reuse and environmental management. In China, decreased land resources and soil fertility is of increasing concern presently, which may threat national food security. Therefore, a range of biochars have been tested for their potential in improving farming soil quality considering the high fertility sustained by biochar in Amazonian Dark Earths locally known as Terra Preta de Indio. Some studies have proved that biochar can play a positive role in improving the fertility of agricultural soils and thus increasing crops yield. Moreover, biochar has also been shown to be effective in control and remediation of a range of soil contamination and hence improve soil environmental quality, leading to increased food output and quality. In the present review, the most recent advances in the effect of biochar on agricultural soil fertility and soil environment quality with the underlying mechniasms are reviewed and discussed here in detail. Firstly, most biochars, particularly those produced from wetland plant residues tend to improve water retention capacity of agricultural soil, especially for those with sandy texture. This phenomenon could be caused by the porous structure of biochar, which can increase the water-holding porosity of soils. Secondly, substantial evidence has shown that the bioavailability of key mineral nutrients increase remarkably in response to biochar application, which could be attributed to the sufficient mineral ash in biochar and relatively high caiton exchange capacity (CEC) originated from the rich surface functional groups of biochar. Thirdly, the alkalinity of biochar, which is most likely resulted from the high mineral content, has exhibited potential in mitigation of soil acidity. As a result, the leaching of essential minerals and associated water eutrophication could be controlled to different degrees. However, the long-lasting buffering performance of biochar in the areas of acid rain is still unknown, which needs long-term monitoring with locating tests. Fourthly, with high CEC and mineral content, biochar could be used as fixing agent to sequester heavy metals in agriculture soils through complexation and precipitation, resulting in decreased transfer and accumulation of heavy metals in food chain. On the other hand, a series of negative impacts of biochar on farmland are also highlighted in this review. First of all, biochar may reduce the aggregation of soil particles, and bring ammonia gas gathered in soils which is detrimental to the soil organisms. Simultaneously, the application of biochar into soil could induce the enrichment of polycyclic aromatic hydrocarbon and heavy metals in uncontaminated farmland as well as decreased nitrogen uptake by crops, All of these potential risks can not be ignored. Full realization and systematic investigation on these hazardous effects of biochar is essential to ensure the safe and efficient application of biochar for the improvement of soil fertility and environmental quality. At last, a range of research gaps and future challenges have been characterized and discussed in detail. To achieve better understanding of the effect of biochar on sustainable agriculture with associated mechanisms, long-term experiments in field scales are needed to investigate the persistent output and biogeochemical behaviors of different kinds of biochar. Besides, more field experiments should be carried out to explore the applicability of biochars in differing regions with specific soil types, which could provide more realistic information to improve the local soils. In parallel, ecological and toxicological effects of biochar should be addressed to identify the potential risks. Finally, more efforts should be paid to establish the regulation framework and reference criterion to ensure biochar quality and evaluate its effect on soil fertility and environmental quality. [ABSTRACT FROM AUTHOR]

Ontology similarity measure and ontology mapping are central contexts for knowledge representation and information processing. An ontology algorithm based on iterated Laplacian semi-supervised learning is proposed. Using iterated Laplacian semi-supervised learning method, all the vertices of the ontology graph are mapped into real numbers. Then, the ontology similarity measure algorithm and the ontology mapping strategy are obtained by comparing the differences of their corresponding values. Two experiments confirm that the new algorithm has high quality for special application fields. [ABSTRACT FROM AUTHOR]

In sound reproduction systems, the configuration of loudspeakers greatly affect the accuracy and efficiency of the performance. Based on boundary surface control principle, an optimization method which combines the transfer function method and QR algorithm is proposed for three dimensional sound reproduction. The loudspeakers indicated by the vectors which are most linearly independent in the transfer impedance matrix, are selected as the optimal sound sources. The sound reproduction tests are conducted with the sound pressure inside the vehicle of constant speed as the optimal objective. Both the results of the optimized loudspeaker system and the original loudspeakers system are compared with the desired sound field. It is shown that the performance of 11 optimized loudspeakers could match the performance of 21 loudspeakers and after optimization, the time required to calculate driving signals of loudspeakers is reduced greatly, which demonstrate the effectiveness of the optimization method. [ABSTRACT FROM AUTHOR]

According to anchor broken, bolt withdrawing and other support problems occurred in a mine pressure bumping roadway of Huating Coalfield, the analysis showed that the available bolt support length in Huating Coalfield was less than a scope of loose circle and anchor length was about 3.5 times longer than the bolt. Due to have poor matching between the bolt and anchor in the mine pressure bumping roadway, which led to make the mine roadway stability lost. The study results showed that the system kinetic energy and deformation energy born by the anchor would be reduced with the anchor length reduced and bolt length increased and anchor length decreased properly could be suitable to the site loose zone and plastic zone scope of the mine roadway and thus the bolt and anchor could be well matched. There-fore, an optimization was conducted on the support parameters, the length of the bolt was increased from 2.4 m to 2.8 m and a row space distance was reduced as 0. 7 mx0. 8 m. The length of the anchor was decreased from 7. 3 m and 8.3 m to 6.5 m, the row space distance was decreased as 1. 0 mx0. 8 m and a yield ring, ball type backing plate and other yield devices were added. The site observation showed that the support method could effectively control the deformation of mine roadway and could basically eliminate the phenomena of anchor broken and bolt withdrawn. [ABSTRACT FROM AUTHOR]

Objective To design a behavioral test for detecting hind limb motor functional deficit in rats after stroke. Methods Rats' sensibility and stability of "hind limb jump onto countertop" were compared with those on ipsilateral cycle and the beam walking 1, 7, 14, 21 and 28d after intracerebral hemorrhage (ICH). Results The duration of ipsilateral cycle was less than 7 days, while that of hind limb jump onto countertop and beam walking was both more than 28 days. The corresponding positive symptoms of these three behavioral assessments were most serious 1d after ICH, dominated by moderate to severe, and gradually decreased afterward. 28d after ICH, the positive symptoms of hind limb jump onto countertop and beam walking were still not fully recovered, and dominated by mild to moderate. By comparison, the sensibility of hind limb jump onto countertop was equal to that of ipsilateral cycle and beam walking, while its stability was superior to that of ipsilateral cycle and equal to that of beam walking. Conclusion The experiment of hind limb jump onto countertop is a sensitive, stable and simple behavioral test to detect rat's hind limb motor functional deficit after stroke. [ABSTRACT FROM AUTHOR]

While satisfying the precondition of the pump efficiency and head, the studies of cavitation performance of mixed-flow pump are carried out based on the cavitation model with the barotropic fluid state equation in order to prevent cavitations occurring as far as possible. The experimental results show that the mixed-flow pump with five blades, designed by velocity coefficient method, is not reasonable due to higher critical net positive suction head under design condition. Consequently, inlet edge shape and thickness of the pump impeller blades, and the variation of blades thickness along flowing direction are optimized using the pump efficiency and head as the objective functions after increasing the pump impeller blade number to seven. Cavitation performances among three types of mixed-flow pump with different blade structures are compared and analyzed. Some useful conclusions are conducted. The critical net positive suction head can be greatly reduced by extending the blade inlet toward the pump inlet properly, attenuating the blade inlet edge and optimizing the blade thickness. The optimized pump efficiency and head are 90. 857% and 163. 86 m respectively, and the critical net positive suction head reaches 28. 64 m which is relatively reduced by 45% compared with that of the original pump with 5 blades. The effective improvement of the cavitation performance in the design condition provides helpful directions for further design and optimization of the mixed-flow pump. [ABSTRACT FROM AUTHOR]

PURPOSE: To analyze the synovial fluid, and explore the significance of fibrin during the formation of intra-articular adhesion (IA). METHODS: Arthroscopic disc repositioning and suturing was performed on patients with temporomandibular joint (TMJ) internal derangement (ID) ranging from stage II to V who visited the TMJ clinic at the Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, between Dec. 27, 2007 and Jun. 16, 2008. The patients' ID stages were classified based on the criteria of Wilkes & Bronstein's classification. 125 samples of synovial fluids were collected before arthroscopic surgery and stored in cold environment. According to the fluorescence intensity of each sample, and the immunofluorescence confocal laser microscopic semi-quantitative analysis was used to determinate the content of fibrin. Student's t test was performed using SPSS16.0 software package, to compare the difference of the average fluorescence intensity of joint fluid in different groups (ID stage, different age, different sex and different joints). RESULTS: There was statistically significant difference in the synovial fluid immune fluorescence intensity in different sex and age group. The average synovial fluid immune fluorescence intensity of all 125 samples was 4.43±3.67 (0-31.68). The average immune fluorescence intensity of each stage was stage II: 2.38±1.17, stage M: 4.68± 3.98, stage IV: 4.80±2.80 and stage V: 3.58±2.64. There was significant difference between the results of stage II and stage HI (P=0.0065<0.05), and there was significant difference between the results of stage II and stage IV (P=0.0207< 0.05). The average immune fluorescence intensity of the male group was 4.05±2.70 and the female group was 5.57±4.71. There was significant difference between the results of male group and female group. The average immune fluorescence intensity of the synovial fluid of left TMJ was 4.37±3.04 and the right TMJ was 5.97±5.20. There was significant difference between the results of the left and right TMJ synovial fluids. The average immune fluorescence intensity of group 1 was 4.55±2.45, group 2 was 4.56±3.39, group 3 was 2.60±1.12 and group 4 was 5.68±6.71. There was significant difference between group 1 and group 3, group 2 and group 3, group 3 and group 4. CONCLUSION: The average intensity of TMJ increased with ID stage, which confirmed that fibrin in synovial fluid is one of the important protein factors during the formation of IA, and verified our hypothesis about the formation of IA. Supported by Shanghai Leading Academic Discipline Project (S30206), Grant from Shanghai Municipal Bureau of Health (2008160), Natural Science Foundation of Shanghai Municipality (10ZR1418200), Ph.D. Programs Foundation of Ministry of Education of China (20090073110068), and Natural Science Foundation of Henan Province (2010C320006). [ABSTRACT FROM AUTHOR]

A latent fault usually leads to great security risk and financial loss. The judgment of unobvious latent fault judgment relies on regular inspection. A regular inspection and periodic maintenance model, which aims to acquire the minimal mean cost of long-term operation of component, was proposed based on the residual life after the occurrence of latent fault, and the influence of accelerating deterioration on maintenance was discussed. The latent fault occurrence can be estimated in time through the regular inspection. Furthermore, the periodic maintenance strategy used after latent fault appearance can make full use of residual life of component and maximize its service life. [ABSTRACT FROM AUTHOR]