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With the increasing importance of mine water prevention and control in coal mining, higher requirements have been put forward for precise seismic exploration methods. Conventional seismic exploration based on isotropy is increasingly unable to meet the high-precision exploration requirements for coal seams and their roof and floor under complex conditions. Based on the orthogonal anisotropy characteristics of coal bearing strata, the periodic thin interlayer anisotropy and fracture induced anisotropy are comprehensively considered. A wide-angle imaging method based on high-order motion correction is proposed to flatten the in-phase axis and improve the accuracy of far and near offset motion correction for the characteristics of the transverse isoropy medium with vertical symmetry axis(VTI). Applying the Offset Vector Tile(OVT) domain processing to eliminate anisotropy in different directions under structural fractures in coal bearing strata, in response to the characteristics of the transverse isoropy with horizontal axis ofs symmetry medium(HTI). Improve imaging accuracy and resolution during seismic data processing. Improve imaging accuracy and resolution during the seismic data processing phase. On the basis of wide azimuth and high fidelity imaging, lithology interpretation is based on the pseudo acoustic method of rock physical characteristics. By reconstructing the acoustic time difference logging curve and incorporating formation lithology information into the velocity curve, the spatial distribution characteristics of formation lithology can be analyzed through inversion iteration. Fracture interpretation is based on ellipse fitting of azimuth offset information contained in OVT gathers to obtain attenuation gradient of seismic wave in different azimuth, and fracture density and azimuth are fitted to obtain distribution characteristics of formation fracture density. To achieve precise exploration of the two key parameters affecting mine flooding, the coal seam roof aquifer and the water conducting fracture zone. On this basis, a comprehensive evaluation is conducted on the water production risk zone of the coal seam roof. The actual water content risk assessment of the data is in good agreement with the production well situation. The method was applied to the research area, and the actual data of water content risk assessment matched well with the production well situation. The results verified the feasibility and applicability of the proposed risk assessment method, providing useful reference for predicting mine flood risk areas in coal mining.

In environmental epidemiological research, extensive non-random environmental exposures and complex confounding biases pose significant challenges when attempting causal inference. In recent years, the introduction of causal inference methods into observational studies has provided a broader range of statistical tools for causal inference research in environmental epidemiology. The instrumental variable (IV) approach, as a causal inference technique for effectively controlling unmeasured confounding factors, has gradually found application in the field of environmental epidemiological research. This article reviewed the basic principles of IV and summarized the current research progress and limitations of applying IV for causal inference in environmental epidemiology. IV application in the field of environmental epidemiology is still in the initial stage. Rational use of IV and effective integration with other causal inference methods will become the focus of the development of causal inference in environmental epidemiology. The aim of this paper is to provide a methodological reference and basis for future studies involving causal inference to target population health effects of environmental exposures in China.

Based on the current situation of emergency recovery equipment of offshore oil spill and the difficulties of offshore heavy oil spill recovery, this paper introduced multiple types of oil spill recovery equipment according to the differences in working principles. The configuration of oil spill recovery equipment in the emergency equipment warehouse of national, local government and oil spill emergency professional company was statistically analyzed. This paper focused on the problems of the existing oil spill recovery equipment in the process of heavy oil leakage disposal, such as the lack of targeted structural design, the lack of heavy oil pumping and transmission capacity, and the lack of pressure bearing capacity of the oil pipeline. Finally, the new oil skimmer and pumping system designed by overseas oil spill emergency equipment manufacturers were introduced to solve the difficult problem of heavy oil recovery, which could provide technical reference for the research of offshore heavy oil recovery equipment in China.

The basic requirement of the 5th Generation (5G) network is to realize automatic end-to-end service arrangement and slice orchestration. In this paper, considering the purpose of the open standardization of the Northbound Interface (NBI) of 5G transport network, we first analyze the functional requirements of the NBI. Then the modeling scheme of the NBI is proposed. Finally, the different technical implementation schemes of 5G transport network are shielded, which provides a reference for the unification of the NBI.

Through artificial water - controlled methods, the effects of drought stress at different growth stages on growth and development and compensatory effect after water recovery of peanut (Arachis hypogaea L. ) were studied under pool culture in water proof installations. The results indicated that the plant height, LAI (leaf area index), the dry weight of shoot and pod of peanut all decreased at various levels. With the prolongation of drought stress treatment, their decrease range amplified under drought stress at diiferent growth stage. The drought stress at pod filling and seedling stage had relatively less effect on plant growth of peanut. The compensatory effect affer water recovery was relatively greater at seedling stage. The drought stress at flower - pegging and pod - setting stage had relatively greater effects on the plant growth of peanut, and the compensatory effect after water recovery was negligible at these stages. The drought stress had the least effect on pod yield of peanut and it had increasingly greater effect at pod fiiling and mature stage, flower - pegging and pod setting stage. The effects of drought stress at seedling stage on pod yield of peanut was mainly relevant to the decrease of valid pod number. The effects of drought stress at pod - fiiling and mature stage on pod yield of peanut was mainly relevant to the decrease of pod plumpness. The effects of drought stress at flower - pegging and pod setting stage on pod yield of peanut were the combined effects of low valid pod number and low pod plumpness. [ABSTRACT FROM AUTHOR]

Based on the long-term located observation of forest ecosystem, and by using the 2006 forest resources inventory data of Liaoning Province and the forest industry standard of the People's Republic of China(LY/T 1721-2008, specification for assessment of forest ecosystem services in China), an evaluation was made on the material quantity and services value of main forest ecosystems in fourteen cities of Liaoning Province. In this province, the forest ecosystem services value supplied by water storage, soil conservation, C fixation, O2 release, nutrients accumulation, environment purification, biodiversity conservation, and forest recreation in 2006 was 2591.72×108 yuan, which was 8.54 times of the forestry production value and 28.02% in the GDP of the province. The services value of water storage, biodiversity conservation, C fixation, and O2 release occupied 79.09% of the total, being the main forest ecosystem services in the province. Economic forest and shrub had smaller per unit services value but larger area, and hence, their ecosystem services value should not be ignored. Abies fargesii forest, Phellodendron amurense forest, Juglans mandshurica forest, and Fraxinus mandshurica forest were the representative zonal vegetations in Liaoning Province, which had high value in biodiversity conservation. Under the effects of climate and other factors, the forest area and forest quality in west Liaoning were lower than those in east -Liaoning. [ABSTRACT FROM AUTHOR]

The frequency scaling algorithm (FSA) was introduced in spaceborne spotlight SAR. As the range time extension of imaged scene is smaller than the width of transmitted pulse, FSA applied in airborne spotlight SAP, dechirps on received echoes and reduce the sampling rate to release the computational burden. In spaceborne SAR, however, the range extension is much larger and the bandwidth after dechirping increases instead so that the existing FSA can not be adopted. To overcome this problem, a method to perform directly frequency scaling on chirps in range direction was proposed. An azimuth compression was applied to reduce PRF in azimuth direction. Finally, simulation results of point targets were given to demonstrate the validity and efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

While integrating with space-time code and orthogonal frequency division multiplexing (OFDM), putting cyclic delay diversity into the traditional space time OFDM coded system, a new space time frequency coded strategy was proposed. In the new coded strategy, symbols on the same sub-carriers between different OFDM frames are to be space-time coded and then transmit diversity could be achieved; proper cyclic delay is used to implement frequency diversity and then those symbols on all sub-carriers in one OFDM frame would be space frequency coded. The tests show that the new strategy has obvious advantages on its simple structure and great improvement on error performance. The new coded strategy can achieve full space-time-frequency diversity over frequency selective fading channel. At the same signal to interference ratio (SIR) level, the error performance of the new coded strategy is better than that of the traditional space time OFDM or space frequency OFDM system. [ABSTRACT FROM AUTHOR]

An efficient space-time-frequency coded OFDM technique for broadband wireless communications was proposed. The proposed scheme adopts subcarrier grouping and linear precoding, which can guarantee the maximum diversity gain and facilitate the process of encoding and decoding. It jointly uses the space time trellis codes (STTC) and the space-time block codes (STBC) to achieve higher coding gain. Power allocation is adopted in the scheme to achieve better bit error rate (BER) performance and higher power efficiency. The proposed scheme is a new approach to space time-frequency coded OFDM (COFDM) that combines OFDM with space-time coding, linear precoding and adaptive power allocation to provide higher quality of transmission in terms of the error rate performance and power efficiency. The significant performance improvement of the design is confirmed by corroborating numerical simulations. [ABSTRACT FROM AUTHOR]

In order to eliminate the Doppler spread effect caused by ionospheric perturbation, an ocean clutter cancellation solution with short dwells was used to HF sky-wave over-the-horizon radar surface surveillance. A singular value decomposition (SVD) based ocean clutter cancellation algorithm and its improved version were introduced to the ship detection. By decomposing the Hankel matrix constructed from the observed signal, zeroing the singular values corresponding to ocean clutter components, and reconstructing the temporal sequence, the ocean clutter can be suppressed. Compared with the existing clutter cancellation algorithms, the proposed algorithm has better suppression performance and it need not estimate the associated parameters or set the iterative ending threshold. The paper also presented an improved scheme on the basis of the SVD algorithm, which can determine effectively different singular values corresponding to the ocean clutter and target signals before cancellation. The improvement algorithm can avoid the incorrect cancellation of target signal significantly in the case of multiple targets or ship echoes with powerful strength. Finally, simulations were given to illuminate the efficiency of the addressed algorithm. [ABSTRACT FROM AUTHOR]

Based on the existing moment-type method, the method windowing the empirical characteristic function (ECF) and a new method estimating parameters of symmetric α stable and Gaussian distributions were proposed. The windowed ECF approximates the characteristic function nearer than ECF itself. The new parameter estimation method overcomes the deficiency of the existing moment-type method that t of ECF must be chosen close to 1, at the same time, it avoids solving complicated equation. The simulations show that the new method is robust. [ABSTRACT FROM AUTHOR]

This paper discussed parallel signal processing for high frequency over the-horizon radar via cluster of workstations (COW), Sun HPC ClusterTools and message passing interface (MPI). There are two key parts of the signal processing algorithms, two-dimensional FFT (Range-Doppler transform) and digital beamforming (DBF). Of the different computing load distribution schemes, the coarse-grained scheme has better performance for MPI, and the scalability of the algorithm was analyzed and discussed for the special hardware and software configure. The simulation results demonstrate that the speed and performance of the parallel scheme are improved evidently. [ABSTRACT FROM AUTHOR]

The resistivity of the anti-corrosion coating of buried steel pipeline is an important parameter.In recent years，the value of this parameter has been used to evaluate the overall quality of the anti-corrosion coating of in-service or directional drilling pipelines.All the domestic standards regarding the on-site measurement of this parameter and the evaluation of the overall quality of the anti-corrosion coating are established with reference to NACE TM 0102-2002.However，those domestic standards have not explained the concept of "anti-corrosion coating resistivity" clearly and there is confusion with terms related to "anti-corrosion coating resistivity".The reasons for selecting the general method and the attenuation method are not defined clearly for the measurement of the resistivity of anti-corrosion coating in various standards，and the test location of the soil resistance is not specified when the general method is used for the directional drilling crossing pipeline，resulting in differences in the field test results and evaluation conclusions of the resistivity of the anti-corrosion coating outside the same pipeline by various inspection units.In order to clarify the above problems，the concepts related to the resistivity of the anti-corrosion coating were explained firstly，and then the meaning of the resistivity of the anti-corrosion coating was clarified through theoretical analysis and formula derivation.Furthermore，the measurement results of the resistivity of the anti-corrosion coating of 100 directional drilling crossing pipelines were statistically analyzed.Finally，suggestions on the revision of relevant standards were given，with expect to revise the unclear problems in the new version of the standards.

Objective: To improve the separation efficiency of constricted clam shell and meat. Methods: Taking Lianyungang double-headed razor as the test object, taking frequency, amplitude, and sieve surface inclination as the test factors, and taking the screening efficiency and the ratio of the shell in the meat as the main control targets, a single-factor test was carried out, and the test results were analyzed by Design-Expert software. An analysis of variance was performed to establish a regression model matching the frequency, amplitude, and inclination of the screen surface to the screening efficiency and the ratio of husks in the meat. Using the response surface optimization analysis method, the optimal matching of working parameters for the separation and screening device of constricted razor shell and meat was obtained. Results: When the discharge rate was controlled at 1.2 kg/s, the shell opening rate was controlled at 97%, the frequency was set at 21.6 Hz, the amplitude was set at 3.6 mm, and the screen inclination angle was set at 9°, the screening efficiency of constricted razor was improved, with the screen efficiency of 97.60%, and the shell-on ratio of the meat of 4.52%. Conclusion: The designed vibrating screening device for constricted razor has high screening efficiency and good adaptability, which can meet the preliminary processing requirements.

A new multifunction X-band electron paramagnetic resonance (EPR) spectrometer is designed and produced, which is equipped with a new operation system based on the EPR control and readout system (CRS). The new continuous-wave (cw) dual-mode resonator and the dielectric resonators for respectively the pulsed EPR and transient EPR (trEPR) are designed purposely. The adoption of CRS system improves significantly the integration and expandability. The spectrometer is equipped with cryogen-free EPR variable temperature system with a range of 6~300 K. Thereafter, three typical samples are used to demonstrate the elegant design of the spectrometer by the cw dual-mode EPR, pulsed EPR and trEPR experiments. Perspectively, this design herein will be a criterion or option of the new generation of EPR spectrometer.

Objective: To systematically evaluate the clinical efficacy of acupuncture for peptic ulcer., Methods: Randomized controlled trials of acupuncture for peptic ulcer were searched from China National Knowledge Infrastructure (CNKI), WanFang Database, Chinese Scientific and Technological Journals (VIP), China Biomedicine (CBM), PubMed and the Cochrane Library from the establishment time of databases to September, 2016. Data extraction and quality evaluation were implemented for the literature which met the inclusive criteria. The RevMan 5.3 software was used to make Meta-analysis., Results: Sixteen papers including 1 570 patients of peptic ulcer were included. The results of Meta-analysis showed that there was no statistical significance between acupuncture and western medicine in the effective rate, the healing rate of ulcer area and the HP negative rate (all P >0.05); the recurrence rate of acupuncture was significantly lower than that of western medicine[RR=0.35, 95%CI (0.14, 0.84), P <0.05]. Acupuncture plus western medicine was significantly different from simple western medicine in the effective rate, the healing rate of ulcer area and the recurrence rate[RR=1.20,95% CI (1.04, 1.38), P =0.01; RR=1.29, 95% CI (1.06, 1.58), P =0.01;RR=0.27, 95% CI (0.16, 0.45), P <0.00001]. The analysis of evidence grade (GRADE) pre-sented that the healing rate of ulcer area and the HP negative rate of acupuncture were "low grade", and others were "extremely low grade"., Conclusions: Acupuncture combined with western medicine has some advantages for peptic ulcer compared with the conventional western medicine, which needs further confirmation due to the lower evidence grade. Larger samples, randomized controlled trials with high quality are highly recommended.

The sweet taste and health effect of Lithocarpus polystachyus are mainly related flavonoid. To obtain Lithocarpus transcriptome database and flavonoid biosynthesis-related genes, the RNA-Seq techology (Illumina HiSeq 4000) was used to sequence its transcriptome. Six Gb database was assembled after assembly steps, and 41 043 of L. polystachyus unigenes were obtained. With blasting them with 7 data banks, all unigenes were involved in 51 GO-terms and 237 metabolic pathways. And furthermore 28 genes of the flavonoid biosynthesis-related were found. After using the MicroSatallite, 18 161 SSR were obtained, the single-nucleotide-repeated was the richest at 7 346. These data represent abundant messages about transcripts and provide valuable genome data sources in molecular biology of L. polystachyus., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

According to the sequence of P450 cDNA of Eleutherococcus senticosus, specific primers were designed. Frokaryotic ex pression vector pET30a-P450 was constructed and the prokaryotic expression conditions were optimized. Results showed that the BL21 after being transformed with the recombinant expression vector accumulated the high amount of recombinant protein. SDS-PAGE analysis showed that the recombinant protein was about 53 kDa. The recombinant accumulated the highest amount of recombinant protein af ter IPTG (1 mmol x L(-1)) at 27-37 degrees C for 24 h. Consequently P450 gene of E. senticosus could be expressed successfully by prokaryotic expression vector pET30a-P450. Induction temperature, IPTG concentration, medium type and amount of induction time could all influence the expression of target protein, but the impact strength was different.

In order to find the characteristics of two members of gene family of squaleneexpoxidase (SE) , a quantitative real time PCR method was developed to analyze the expression of Eleutherococcus senticosus SE1 and SE2 gene from different growth periods and in different organs. The result indicated that all the expression of SE2 more than SE1 in the whole growth period and organs of E. senticosus. And in the whole growth period, expression of SE1 showed a low-high-low characteristic. Both expression of SE2 and growth period showed the same trend. The lowest content of the expression was in the roots. SE1 expression have been improved more than SE2 when treated with MeJA. The expression of E. senticosus SE1 and saponins content had significantly positive correlation (P < 0.05) and the correlation coefficients was 0. 858, while the correlation was not significant for SE2. That indicated that SE1 played a key enzyme gene in the biosynthesis of triterpenoidsaponins

The transient photochemical behavior of xanthone (XAN) in 1-butyl-3-methyl imidazolium hexafluoride phosphate ionic liquid ([bmim][PF6]) or binary mixed solution with acetonitrile (MeCN) was investigated by nano-second laser photolysis techniques. The spectral blue shift of 3XAN* was observed in the neat [bmim][PF6] or IL/MeCN mixture solution compared to MeCN solution. And the yield was also increased. Moreover, the energy transfer rate constant of XAN and naphthalene (NAP) was affected by the concentrations of ionic liquid. The values decreased rapidly with increasing VIL. For example, the values were 1.2 x 10(10) mol x L(-1) x s(-1) in MeCN, and 1.1 x 10(8) mol x L(-1) x s(-1) in [bmim][PF6], respectively. The photo-induced electron transfer between XAN and N,N-dimethylaniline was also investigated by changing the concentrations of [bmim][PF6] in binary solution.

Objective: To analyze the codon usage of chloroplast genome and the influencing factor in Eleutherococcus senticosus., Method: Codon of 52 genes, which were selected from the chloroplast genome sequence of E. senticosus, was multivariate statistical and correspondence analyzed using CodonW and SPSS software., Result: GC content at the three position of codons by turns was 46.46%, 38.26%, 29.88%, whereas GC1 and GC2 had a significant correlation coefficient (P < 0.01). The correlation coefficient with GC12, and GC3 was 0.205 and was not significant correlated. There were 30 codons which relative synonymous codon usage was greater than 1 and 29 codons end with A and T. In the corresponding analysis, the first axis shows 10.35% variation. And there was significant correlation coefficient between ENC and GC3. The correlation coefficients with GC3 and ENC were -0.288 and 0.353, respectively. We defined 16 codons from 16 amino acids as the major preference codons in chloroplast genome of E. senticosus., Conclusion: The third positions for all codon are preferred to ending with A and T. The codon usage bias is formed under effect of mutation and selection, as well as other factors. But the selection will have a far greater impact than others.

Objective: To analyze the expression differences of SS, SE and bAS in leaf, petiole and callus from leaf and petiole of Eleutherococcus senticosus., Methods: Calluses were induced from explants of E. senticosus leaf and petiole. The expression amount of SS, SE and bAS gene was detected by real time PCR., Results: The expression amount of SS, SE and bAS genes in callus from leaf were 89.3%, 73.8% and 83.4% of that in leaf, respectively. The expression amount of SS, SE and bAS genes in callus from petiole were 80.2%, 87.7% and 70.9% of that in petiole, respectively., Conclusion: The expression amount of SS, SE and bAS gene in callus from E. senticosus are significantly lower than that in plant.

The photochemistry of pyrene in conventional solvents (acetone, acetonitrile, cyclohexane) and ionic liquids [Bmim] [PF6], [BuPy][BF4], R4 NNTf2 was investigated by time-resolved laser photolytic techniques. The transient absorption spectra of the excited pyrene and other radical species were compared. The absorption band of pyrene cation radical was observed in the acetone, acetronitrile and pyridinium ionic liquid [BuPy][BF4] systems. Only excited triplet pyrene was observed in cyclohexane and [Bmim][PF6] and R4 NNTf2. The result demonstrates that there was an interaction between pyrene and solvents, and the pyrene cation radical was formed by electron transfer from the excited state of pyrene to acetonitrile, acetone and [BuPy][BF4]. The possible mechanisms of the six systems were suggested.

Based on the long-term located observation of forest ecosystem, and by using the 2006 forest resources inventory data of Liaoning Province and the forest industry standard of the People's Republic of China( LY/T 1721-2008, specification for assessment of forest ecosystem services in China), an evaluation was made on the material quantity and services value of main forest ecosystems in fourteen cities of Liaoning Province. In this province, the forest ecosystem services value supplied by water storage, soil conservation, C fixation, O2 release, nutrients accumulation, environment purification, biodiversity conservation, and forest recreation in 2006 was 2591.72 x 10(8) yuan, which was 8.54 times of the forestry production value and 28.02% in the GDP of the province. The services value of water storage, biodiversity conservation, C fixation, and O2 release occupied 79.09% of the total, being the main forest ecosystem services in the province. Economic forest and shrub had smaller per unit services value but larger area, and hence, their ecosystem services value should not be ignored. Abies fargesii forest, Phellodendron amurense forest, Juglans mandshurica forest, and Fraxinus mandshurica forest were the representative zonal vegetations in Liaoning Province, which had high value in biodiversity conservation. Under the effects of climate and other factors, the forest area and forest quality in west Liaoning were lower than those in east Liaoning.

Background & Objective: In order to improve quality assurance (QA) and quality control (QC) of radiotherapy, individualized vacuum bag is used in the localization of radiation treatment, gradually becoming one of the important steps for the QA and QC in the many departments of radiation oncology. It is controversial whether localization with vacuum bags under the simulator influences the precision of direct measurement for tumor depth in the isocentric posterior oblique field in the patients with thoracic and abdominal tumors. This study was designed to explore the influence of vacuum bag on the direct measurement, Methods: Twenty-nine patients with thoracic and abdominal carcinoma who had to need isocentric irradiation in the supine position were immobilized using vacuum bag. The irradiation depths of 45 posterior oblique fields were determined by CT-simulator and conventional simulator, respectively; then the absolute value for the difference of both depths was regarded as error value., Results: There were 37 fields (82.2%) with error value of smaller than 5 mm; 8 fields (17.8%), more than 5 mm. In the latter, 5 field were belonged to be repositioned in the phase II of radiotherapy because of light leaking air into the vacuum bag in the phase I of radiotherapy., Conclusion: Vacuum bag has a slight influence on direct measurement for depths of isocentric posterior oblique field.