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Because of the existence of primary user signals and the inevitable nonlinearity of some RF devices,the inter-ference signals such as three-order intermodulation signal would be produced in the front-end of RF receiver.To reduce the impact of interference signals,the interference which was caused by primary user signals to dynamic spectrum shar-ing wireless communication system was analyzed on the front-end of RF receiver side.Then,the restriction on opera-tional channel selection of dynamic spectrum sharing wireless communication system was derived.By following the re-striction,the negative effects caused by interference signals could be reduced and the quality of communication in dy-namic spectrum sharing system was guaranteed.Finally,availability of the restriction on operational channel selection is verified experimentally in UHF dynamic spectrum sharing wireless communication system.

A signal-to-interference-plus-noise ratio（SINR） performance analysis method of discrete fourier transform spread generalized multi-carrier（DFT-S-GMC） system was proposed.The closed-form SINR expression based on simpli-fied frequency-domain equivalent implementation structure and MMSE equalization for receiver is derived by channel frequency response and noise variance,considering inter-block（IFBT symbol） residual interference multiplexed in time domain.Moreover,it can be easily extended to multi-receive antenna.By simulation results,it is shown that with pro-posed equivalent SINR,the BLock error rate（BLER） performance of DFT-S-GMC over slow fading channel is well matched with that over AWGN channel.

In order to identify the pathogen and its characteristics in diseased Cuora flavomarginata in Hangzhou, Zhejiang, in June 2020, a dominant strain HZ202006 was isolated from the liver of the diseased turtles. Morphological observations, 16S rRNA sequence analysis, whole-genome sequencing, artificial infection experiments, and antimicrobial sensitivity test were performed on this strain. The results confirmed that the strain is Providencia rettgeri, a short rod-shaped, Gram-negative bacterium. Whole-genome sequencing revealed that the complete genome sequence of this strain consists of a 4.8 Mbp double-stranded DNA and two plasmids. Annotation of the sequenced genes using the Comprehensive Antibiotic Resistance Database (CARD) and the Virulence Factors Database (VFDB) identified 20 resistance genes and four virulence factors in the bacterium. Antimicrobial sensitivity test demonstrated that HZ202006 was moderately sensitive only to amikacin, and resistant to 16 common antibiotics, including penicillin, cephalosporins, and aminoglycosides. This study isolated and identified a strain of P. rettgeri causing disease in C. flavomarginata, providing insights for disease control in aquaculture animals affected by this bacterium. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to investigate the effects of different dietary types on feces and urine production, organic matter, chemical oxygen demand (COD), nitrogen, phosphorus, copper and zinc content and production in feces and urine of Inner Mongolia white cashmere goats. Twenty-four Inner Mongolia white cashmere goats of eight months old with similar weight were randomly divided into four groups: Alfalfa green hay group (G1), alfalfa green hay supplemental concentrate group (G2), corn straw group (G3), and corn straw supplemental concentrate group (G4) (the supplemental feeding amount of each goat was 200 g, the ratio of concentrate to coarse was 2.5:7.5, other feeding conditions are the same), with six replicates per group, and one sheep per replicate. The pre-test period was 10 days, and the formal test period was 30 days. The results showed that the amount of fresh feces in the G2 group and G4 group were significantly higher than those in the G1 group and G3 group (P<0.05), and the mass of dry feces was extremely higher than that in the G1 group (P<0.01). Cu content in feces of the G1 group and G2 group was extremely higher than that of the G3 group and G4 group (P<0.01). The emissions of organic matter and zinc in feces of the G2 group and G4 group were significantly higher than those of the G1 group and G3 group (P<0.05), and the emissions of phosphorus were significantly higher than those of the G3 group (P<0.05). The fecal copper emission of the G2 group was extremely higher than that of other groups (P<0.01), and that of the G1 group and G4 group was extremely higher than that of the G3 group (P<0.01). Nitrogen content and emission in urine of the G2 group were extremely higher than those of other groups (P<0.01), while the phosphorus content and emission in urine of the G1 group and G3 group were significantly higher than those of the G1 group and G3 group (P<0.05). The study indicates that the feed formula suitable for Inner Mongolia white cashmere goats can be adjusted according to the amount of feces and urine produced by various diets and the excretion law of pollutants in feces and urine, which can not only meet the production needs of animals, but also reduce the excretion of pollutants. [ABSTRACT FROM AUTHOR]

Objective: To analyze the independent risk factors for the occurrence of moderate-to-severe metabolic-associated fatty liver disease (MAFLD), to construct a prediction model for moderate-to-severe MAFLD, and to verify the validity of the model. Methods: In the first part, 278 medical examiners who were diagnosed with MAFLD in Medical Examination Center at the Second Affiliated Hospital of Hainan University from January to May 2022 were taken as the study subjects (training set), and they were divided into mild MAFLD group (200) and moderate-severe MAFLD group (78) based on ultrasound results. Demographic data and laboratory indexes were collected, and risk factors were screened by univariate and multifactor analysis. In the second part, a dichotomous logistic regression equation was used to construct a prediction model for moderate-to-severe MAFLD, and the model was visualized in a line graph. In the third part, the MAFLD population (200 people in the external validation set) from our physical examination center from November to December 2022 was collected as the moderate-to-severe MAFLD prediction model, and the risk factors in both groups were compared. The receiver operating characteristic (ROC) curves, calibration curves, and clinical applicability of the model were plotted to represent model discrimination for internal and external validation. Results: The risk factors of moderate-to-severe MAFLD were fasting glucose (FPG), blood uric acid (UA), triglycerides (TG), triglyceride glucose index (TyG), total cholesterol (CHOL), and high-density lipoprotein (HDL-C) . UA [OR=1.021, 95% CI (1.015, 1.027), P<0.001] and FPG [OR=1.575, 95% CI (1.158, 2.143), P=0.004] were independent risk factors for people with moderate to severe MAFLD. The visualized line graph model showed that UA was the factor contributing more to the risk of moderate to severe MAFLD in this model. The ROC curves showed AUC values of 0.870 1, 0.868 6 and 0.799 1 for the training set, internal validation set and external validation set, respectively. The curves almost coincided with the reference line after calibration of the model calibration degree with P>0.05 in Hosmer- Lemeshow test. The decision curve analysis (DCA) plotted by the clinical applicability of the model was higher than the two extreme curves, predicting that patients with moderate to severe MAFLD would benefit from the prediction model. Conclusion: The prediction model constructed by combining FPG with UA has higher accuracy and better clinical applicability, and can be used for clinical diagnosis. [ABSTRACT FROM AUTHOR]

Logging Technology has been being widely used in the fields of coal field, natural gas, freshwater resources, petroleum and solid minerals, which has gained lots of achievements and experience, but it is seldom used in the exploration of deep brine resources. By studying the logging results of many projects such as Exploration of Mahai Deep Brine Potassium Deposit in Lenghu Town of Qinghai Province, the paper summarizes the characteristics of parameters including laterolog-3 resistivity, natural gamma-ray, sonic differential time and spontaneous potential in Cenozoic strata, and finds the common logging method being an indispensable guide to the exploration for salt lake resources, particularly for deep brine resources. The relation between characteristics of logging curves and single well sequence is found through statistical analysis of large amounts of logging data in the basin. Then the quantitative recognition is used to analyze and verify the parameter range and curve characteristics of natural gamma-ray and sonic differential time, and the logging interpretation method suitable for deep brine exploration in Qaidam Basin is summarized finally. [ABSTRACT FROM AUTHOR]

Ancient Shanghai has a long history of participating in economic and cultural exchanges along the maritime silk road. Shanghai area was an important hub of Buddhist cultural exchanges between China and Japan in ancient times, especially in Song and Yuan dynasties. During this period, there are two major events worth studying. First, a famous Japanese monk named Junreng came to China to study Buddhism in Song Dynasty and then returned to Kyoto to spread it. Second, a monk named Qingzhuo Zhengcheng came to Shanghai to teach the dharma and then he was invited by the upper class in Japan to teach the dharma there, which had a far-reaching influence. These is not only the historical witness for ancient Shanghai to participate in Sino-Japanese Buddhist exchanges and play an important role in geography, but also a reflection of the development status of Buddhism in Shanghai during the Song and Yuan dynasties. In the Song and Yuan dynasties, there was a certain time gap between the development of Japanese Buddhism and Chinese Buddhism, which strengthened the need and possibility for Japan to learn Chinese Buddhism in different periods. Located in the southeast coast, Shanghai is the seaport of the economically and culturally developed Jiangnan (regions south of the Yangtze River) region. With a relatively high level of local economic, transportation and cultural development, Shanghai attracted famous monks to come and preserved a large number of classics. In addition, Shanghai could take both advantage from Jiangnan region and the Maritime Silk Road to find opportunities. [ABSTRACT FROM AUTHOR]

In consideration of the on-station wagon operation anomaly situation, an anomaly detection algorithm of on-station wagon operation rime (WOT) was proposed based on BIRCH- LKD. This algorithm was focusing on the WOT sequence and converting the sequence into the spherical cluster with WOT feature vector, without considering the peculiar form of the anomaly. A feature clustering tree of WOT feature vector was developed based on the classification rule to be utilized in the dominant anomaly detection and shortening survey range. After computing the K-distance of the other data object, according to the different variation, the appropriate sequence values were selected as the recessive anomaly. At last, the lower bound of WOT was excluded by using the median anomaly condition. The results show that the algorithm has a high detection rate. The anomaly of the WOT sequence can be identified quickly, and the accuracy can be more than 85%. The WOT sequence becomes more smooth and unbroken after the removal of the anomalies, and conforms to the actual development trend. [ABSTRACT FROM AUTHOR]

The hexagonal wurtzite Gallium nitride(GaN) was prepared by calcining β gallium oxide(β-Ga2O3) in flowing ammonia. The XRD, SEM and TEM were employed to investigate the structure and morphology. The photoluminescence (PL) spectroscopy was used to collect photoluminescence spectroscopy of GaN perform the luminous property. The measurement results revealed that the obtained GaN had preferred orientation of (002), and the rod shape and grain size of GaN powders were similar to those of raw gallium oxide which were agglomerates of tens nanometers flake crystallites. The near-edge emission at 346 nm(3.584 eV) of Gallium nitride powders had a blue shift of 19 nm(187 meV) than that of bulk GaN material. [ABSTRACT FROM AUTHOR]

In order to study various temporal dependencies and the relationship between the various attributes more efficiently in the temporal database, this paper investigated the temporal candidate keywords and firstly proposed the notions of temporal quasi left attributes, temporal quasi right attributes and temporal pure double attributes. It combined with relational database theory, gave the temporal maximum relative block method to obtain the temporal candidate keywords. And it demonstrates the relevant theorems and deductions. This is an important role in promoting the standardization of temporal candidate key. [ABSTRACT FROM AUTHOR]

Data race Is a common problem in muldthreaded programs. Due to the state explosion of thread interleaving. it Is difficult to accurately detect bugs triggered by data races. Moreover, it is hard to replay and triage such bugs because of the facts that thread scheduling is difficult to control and the number of interieaving is astronomically large. A data race detection and witness generaion method for multithreaded programs is proposed. A semantic model is designed to encode the execuion path and the condition of data races as first-order logic formula. The satistfablity of the formula, solvable by constraint solvers, indicates the existence of data races under multiple thread inteneavings without requiring repeated execuions. The solutions produced by an SMT solver serve as witnesses to localize and verify data races. In the experiments, we compare existing tools threadsanitizer and helgrind with ours to detect the data races for 10 multithreaded programs. It ss shown that our method can detect 287.5% and 264.7% more bugs respetvely without false alarm, while the false alarm positive rate of threadsanitizer and helgrind are 10.5% and 9.8%. [ABSTRACT FROM AUTHOR]

In order to improve the production capacity of a coalbed methane well, the paper analyzed the coalbed methane drainage mechanism and gas drainage stage. From a geological structure, roof and floor lithology, fracturing liquid, well net layout and other aspects, the paper discussed the main factors affected to the coalbed methane drainage in Tunliu Minefield. The study held that the fold would highly be affected to the drainage effect of the coalbed methane well and the breaking of the roof and floor would be certainty affected to the coalbed methane drainage. The fracturing technology was applied to the intensified reconstruction of the coal reservoir, the assistant drainage effect of the activated water + nitrogen gas fracturing liquid system was better than the activated water fracturing and the assistance drainage effect of the clean fracturing liquid was the worst. The coal reservoir features of the study zone determined that the coalbed methane well within Tunliu Minefield would be hard to have a high production, but could have a long production time. The study held that the well net of the coalbed methane wells in the study zone could be small well net structure with an inter-row distance of 200 mx250 m and the layout of well position should be parallel to the extension direction (northeast direction) of the main fracture. [ABSTRACT FROM AUTHOR]

By means of the fractional ultrasonic-extraction mode, four different-rank coals, including lignite, coking coal, low- and mid-metamorphism anthracites were extracted by different solvent, and X-ray diffraction (XRD) was applied to investigate the microcrystalline structure parameters. The results reveal that, as the increase of coal metamorphism degree, the yields of fractional extraction show the similar trends, i. e. the extraction yield of coking coal is the largest, followed by the lignite and anthracites. For the four coals, the yield extracted by tetrahydrofuran (THF) is more than those by the other three solvents. The comparison of the extraction yields under the other three solvents, controlled by the maceral and chemical composition of coals, shows different trends. Further, the aromatic lamellae spacing (d002) of all residues is lesser than that of all raw coals, but the diameter (La) and the stack height (Lc) of aromatic layer appear slightly increasing trend. The research concludes that different microcrystalline structure parameters of coal have different evolution mechanism under fractionally extracted by solvents; La is affected by swelling degree of coal microscopic structure, Lc done by swelling degree and the amount of small molecular compounds dissolved out of coal body, and d002 comprehensive done by swelling degree, the amount of dissolved-off small molecular compounds and the hold-up solvent molecules. But the increase in stack layers N of aromatic layer is just because of the increase of calculation value obtained by the various aromatic lamellae spacing d d002 and the stack height Lc rather than that in fact. [ABSTRACT FROM AUTHOR]

In order to study the chemical structure and composition characteristics of tectonic coal, the authors collected primary structure coal and tectonic coals (cataclastic coal, granulated coal, mylonitic coal) from underground Sihe Mine in Qinshui Basin. After organic solvent extraction of four coal samples, microcrystalline structure parameters of coal samples were analyzed with modern technology (NMR, XRD, FTIR). The results showed that micro-chemical composition features, macromolecular structure arrangement and the main functional groups composition were different with primary structure coal. The paper revealed mylonitic coal had the highest ordering degree, its evolution degree was ahead of primary structure coal. And in this process, the hydrogen bond fell off, the content of methane gas increased, aliphatic hydrocarbons content decreased, the aryl group polycondensation degree increased. Meanwhile, the paper revealed from microscopic view that mylonitic coal developed area was proned to coal and gas outburst. [ABSTRACT FROM AUTHOR]

In order to know about the composition information of the basic structural units of low metamorphic coals, by means of X-ray diffractometer (XRD) and High resolution transmission electron microscopy(HRTEM), the paper contrastively discussed the arrangement mode of macromolecular structure and the change laws of lignite coal, exampled by Longkou lignite, before and after be fractionally extracted by different solvent. The results reveal that, as the extraction stages increase, the aromatic layer spacing shows a reduction trend, but the length and width of aromatic layer both appear increasing trend. However, these change laws of all the parameters of coal microcrystalline structure are caused by different swelling mechanisms. Comparison by the other extraction residues, the transmission electron microscope images of the raw coal are more clear, and the structure and the arrangement mode of the aromatic layer more uniform. With the increasing of the extraction stages, the clarities of high resolution images of the residues get weak. The macro-molecular structure of the lignite is mainly made up of 2-3 carbon net layers with directional arrangement, and single carbon net layer scatters in local area by the mode of deflection shape, wormlike shape or cross shape. The ultra-micro-pores mainly include the spaces in different BSU or the carbon net layers in the same BSU. [ABSTRACT FROM AUTHOR]

Morality is in essence an indicator of practical reason for lifestyle. It does not only exist in our daily life but also helps construct our world of values on the basis of our daily life. The decline and distortion of morals are due to an unprincipled lifestyle. The key to moral problems lies in the improvement of human way of living : on the social level we have to reform the ways of production and living to make them more reasonable and on the part of individuals strengthen our own sense of moral constraints. [ABSTRACT FROM AUTHOR]

A decoupling control strategy is proposed for looper strong coupling control system of hot strip rolling. Based on predictive control theory, a double-inputs-double-outputs control system could be divided into two SISO subsystems, the controller of each subsystem be updated sequentially in a sampling time, and the future control information be kept and used to compensate the coupling effect among subsystems. Control theory is used to reject error disturbance between the future control information and actual value. Above decoupling control strategy could simplify the design of controller, reduce computation load and improve control precision. Finally, simulation results show that the proposed control strategy has better decoupling and control performance. [ABSTRACT FROM AUTHOR]

CFD method has the advantage of well simulating the flow over wind farm of complex terrain, compared with the method of using the software WAsP with linear model, thus becoming the development direction of assessment of wind resources in complex terrain. In order to use the CFD package FINE/TURBO and standard k-ε turbulence model with wall function in the wind resources assessment and micrositing of wind farm in the complex terrain, in this paper, Island Nanao had been simulated in wind directions at intervals of 30 degrees, under the assumption of neutral condition, to investigate the influence of inlet condition on the results. The simulation results show that the wind speed-up and intensity don't change essentially under different inlet conditions. Based on this law, with whole year wind data, an assessment method with post processing has been built, providing a strong reference for engineering practice. [ABSTRACT FROM AUTHOR]

With the aid of analyzing interacted effect of rolling speed increment on looper systems in hot strip finishing rolling, the model of interconnected looper system was established. Based on H. control theory and considering the coupled effect between looper height and looper tension systems as disturbance factor, the looper controllers for each rolling mill were designed using decentralized control strategy. Simulation results show the effectiveness of the algorithm and the good control performance of the looper system. [ABSTRACT FROM AUTHOR]

In this paper, vehicle platoon spatially invariant interconnected systems are modeled as multidimensional systems by introducing spatial variables and spatial shift operators. The multi-object distributed H2/H∞ control method is investigated based on the model. Distributed output feedback controllers, which have the same structure as the plants, are designed to ensure that the systems have both good dynamic characteristic and system outputs to be as little as possible. Finally, vehicle platoon interconnected system is simulated by mass-spring model and the results demonstrate the correctness of the model and effectiveness of the method. [ABSTRACT FROM AUTHOR]

MCM-41-supported Ni2P, MoP and WP catalysts were prepared by an in-situ temperature programmed reduction method from their oxide precursors and characterized by XRD and CO chemisorption. The hydrodesulfurization(HDS)performances of the three catalysts were evaluated using a model fuel containing 0.8% dibenzothionphene(DBT)in decalin. The results indicate that MCM-41-supported Ni2P catalyst shows the highest HDS performance, exhibiting the highest HDS reaction rate constant and TOF, while WP/MCM-41 is the lowest. The HDS reaction routes over the three catalysts exhibit different trends towards different temperatures. The presence of H2S in the feed significantly suppresses the hydrogenation pathway of Ni2P/MCM-41,and leads to a drastic decrease in the HDS activity. MoP/MCM-41 exhibits better sulfur resistance compared with other catalysts. [ABSTRACT FROM AUTHOR]

Binary systems containing ionic liquids are new working pairs in absorption heat pumps. Ionic liquid,1-ehtyl-3-methylimidazolium diethylphosphate([EMIM][DEP]), was synthesized. Vapor pressures for binary systems of[EMIM][DEP] + H2O and [EMIM][DEP] + C2H5OH were measured at different concentrations and temperatures. The experimental data show a considerable negative deviation of vapor-liquid equilibrium from Raoult's law.The vapor pressure data are correlated by NRTL model. NRTL parameters are obtained. The average relative deviation between experimental data and correlated ones are 2.72%, 2.36% respectively. [ABSTRACT FROM AUTHOR]

Two groups of specimens including 8 stub columns were tested to study the effect of bond stress between steel tube and core concrete on the axial loaded behavior of tubed high-strength stub columns ( HSC ). Each group included two columns without bond stress and two columns with bond stress. Elastic-plastic analysis on the steel tube during the loading procedure was carried out. The results from test and analysis indicate that the longitudinal stress of the steel tube is evidently decreased in respect that the bond effect is eliminated, while the bond stress has little effect on the axial load strength and ductility of tubed HSC. Therefore it is not necessary to eliminate the bond effect between the steel tube and the core concrete in structural engineering. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the clinical effect of E-max porcelain laminate veneer on esthetic restoration for anterior teeth over 2 years. METHODS: E-max porcelain laminate veneer was used in 45 patients with 120 defective anterior teeth. Improved Ryge veneer reexamination standards including the integrity of ceramic veneer, marginal adaptation, gingival health and color match were adopted to evaluate the of clinical effect during 2 years of follow-up. RESULTS: The average satisfaction rate instantly after treatment, 1 year after treatment and 2 years after treatment was 93%, 95% and 94%, respectively. CONCLUSIONS: E-max porcelain laminate veneer has fewer side effects, better aesthetics and biological characteristics. The treatment is cost-efficient, safe and long-lasting. [ABSTRACT FROM AUTHOR]

Objective To observe the injury of intestinal mucosal barrier and the expression of autophagy protein in colon tissue of rats with chronic renal failure. Methods Thirty SPF healthy male SD rats were randomly divided into sham operation group (10 rats) and model group (20 rats). The model group was given adenine 200 mg/(kg·d) by gavage for 4 weeks after left nephrectomy. The general conditions of rats were observed. Serum, renal tissue and colon tissue samples were collected at 4 and 8 weeks after gavage. The levels of serum creatinine, urea nitrogen, TNF-α, IL-6 and LPS were measured by ELISA. Renal and colon tissue were examined by HE staining and microscopy. The protein expressions of LC3, beclin-1, ZO-1 and claudin-1 were detected by Western blot. Results Compared with the sham operation group, the model group rats gradually showed a slow response to external stimuli, slow action, withered and yellow hair color, dull luster, pale conjunctiva and slow weight gain. The levels of serum creatinine, urea nitrogen and inflammatory factors in the model group were all higher than those in the sham operation group, and increased at 8 weeks compared with 4 weeks (P＜0.05). Renal pathology in the model group showed renal tubular dilatation, lymphatic and monocyte infiltration, glomerulosclerosis and interstitial fibrosis. Histopathology of colon in model group showed atrophy and collapse of intestinal villi, infiltration of inflammatory cells in mucosal layer and aggravation of pathological changes, which was more serious at 8 weeks than at 4 weeks. The expression of LC3Ⅱ/Ⅰ, Beclin-1, ZO-1 and Claudin-1 in the model group decreased as compared to those of sham operation group(P＜0.05), and much decreased at 8 weeks as compared with 4 weeks (P＜0.05). Conclusions Autophagy disorder may be a potential mechanism causing intestinal mucosal barrier injury in rats with chronic renal failure.

In order to study the behaviors of designers in collaborative production development process and the typical problems of process management, an integrated model of agent-oriented dynamic simulation based on CAS and MAS theory was set up firstly. The integrated model included 4 important parts: Designer agents, arbitration agent, environment objectives (task, resource and product information) and function model of the dynamic simulation system. Secondly, simulation system development method was introduced, and simulation process, class packaging, and functions calling process were described in detail. Lastly, the proposed method was applied on some motorcycle engine development project. The simulation results show that agent-oriented simulation can provide scientific and quantized decision basis, simultaneously, provides a new idea for behavior study of designers in the process. [ABSTRACT FROM AUTHOR]

Polymer flooding is an important technology for enhanced oil recovery. In this paper, an optimal control model is built for making the dynamic injection strategies of polymer flooding, in which the maximum of profit is as the performance index, the fluid flow equations of polymer flooding is as governing equations, the maximum polymer usage and bound constraints of polymer injecting concentrations are as inequality constraints. The size and concentration of slugs, and the ending time of polymer flooding are chosen as control variables. For this distributed parameter optimal control problem, an iterative dynamic programming with variable stages numerical algorithm is proposed. Firstly, the free final time optimal control problem of polymer flooding is transformed into a fixed final time problem by introducing a normalized time variable. Then the size and concentration of slugs, and the ending time of polymer flooding are optimized at the same time using classical iterative dynamic programming. Finally, the numerical results of an example illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In order to understand the status of heavy metal pollution and the resulting ecological risk of farmland soil surrounding the manganese mining area, 174 soil samples were collected, and the heavy metals(Cu, Zn, Pb, Cr, Ni, Mn, As, and Hg) were analyzed. Principal component analysis (PCA) and the positive matrix factorization (PMF) model were used to determine the source of heavy metals in the soils. The single-factor pollution index method, geo-accumulation index method, potential ecological risk assessment method, and US EPA health risk assessment model were used to evaluate the ecological environment risk of heavy metals. The results showed that the average values of Cu, Zn, Cr, Ni, Mn, and Hg exceeded the background value of Guizhou. 100% of Zn samples and 38.86% of Cu samples exceeded the risk screening value for agricultural land soil pollution. Source analysis revealed that the main sources of soil heavy metals were mining emission, mixed agricultural activity and transportation, nature, and agricultural activities. The risk evaluation showed that Ni, Cr, Pb, and As belonged to the clean level, Hg and Cu were in a light pollution stage, Zn fell into the category of moderate contamination, and Mn reached the heavy pollution level. Cu, Zn, Pb, Cr, Ni, Mn, As, and Cd posed low potential ecological risk, while Hg caused a considerable potential ecological risk. In total, the integrated potential ecological risk of heavy metals was ranked "strong", eight types of heavy metals had carcinogenic risks and non-carcinogenic risks for children aged 0-5 years, and the main contributing factors were Cr and Mn, respectively.

Shizuishan is a typical exhausted resources-based city in the northern area of the Ningxia Hui autonomous region in China. In order to develop the planting industry of selenium (Se)-rich agricultural products and promote green and sustainable urban development and transformation, investigations on the quality of Se-rich land were carried out in Shizuishan City, where 7399 surface soil (0-20 cm) samples of farmlands, 30 atmospheric precipitation samples, and nine parent rocks were collected. By means of semi variogram model construction by GS + , Kriging interpolation in ArcGIS and statistics via SPSS, such as correlation analysis and mean-value analysis, the content, spatial distribution, and enrichment factors of Se-soil were analyzed. Further, the enrichment characteristics of soil Se in alkaline conditions were summarized. The results indicated that ω (Se) in surface soil was (0.26±0.12) mg·kg -1 , and its spatial distribution was highly auto-correlated. The variation in Se content was related to natural factors. Along Helan Mountain, the content of Se in the surface soil was comparatively higher than that where coal mines were located. The parent rock was the principal factor that controlled the enrichment of soil Se. The physical and chemical properties of soil such as organic material, pH, and iron and manganese oxides had crucial effects on the enrichment of soil Se in a surficial environment. Compared to a strong alkaline environment, alkaline conditions were beneficial for the enrichment of Se in the surface soil.

Objective: To investigate the protective effects and potential mechanisms of estrogen modified human bone marrow mesenchymal stem cells (hBMSC) on high glucose (HG)-induced injury of vascular endothelial cells. Methods: hBMSCs were cultured under 30 mmol/l glucose to establish a high glucose model (HG), and then were divided into four groups as following: HG group (HG control, without any treatment), HG+E2 group (cells were treated with 20 μmol/L estrogen), HG+E2+ Triciribine group (cells were pretreated with 5 μmol/L protein kinase B (PKB/Akt) inhibitor for 45 min, and then modified by 20 μmol/L estrogen), and NG group (cells were cultured under normal conditions). After 12 h treatment, the cell viability of hBMSC was detected by CCK8 assay, and the contents of NO, VEGF and IL8 in the supernatant of cultured medium in each group were detected by nitrate reductase and ELISA assay (n=6). After 48 h, the expression levels of endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS (p-eNOS) were detected by Western blot (n=3). In addition, the cell supernatant of each group was further extracted as conditioned medium to culture HUVECs, and the cells were subsequently divided into HG-CM group (HUVECs were treated with HG group's conditioned medium), HG+E2-CM group (HUVECs were treated with HG+E2 group's conditioned medium), HG+E2+Triciribine-CM group (HUVECs were treated with HG+E2+ Triciribine group's conditioned medium) and HG-H group (HUVEC were cultured under HG condition, which were treated with final concentration 30 mmol/l glucose). The cell viability of HUVECs in each group was detected by CCK8 assay after 12 h cultured (n=6). After 24 h treatment, the apoptosis rate of HUVECs in each group was detected by flow cytometry (n=3). Furthermore, the migration rate of HUVECs in each group was observed by wound healing assay after 48 h cultured (n=3). Results: Compared with NG group, the cell viability and eNOS protein phosphorylation level of hBMSC in HG group and the contents of NO, VEGF and IL-8 in the supernatant of cultured medium were decreased (P<0.05). Compared with HG group, the cell viability and eNOS protein phosphorylation level in HG+E2 group and the contents of NO, VEGF and IL-8 in cultured medium supernatant were increased significantly (P<0.05), whereas pre-treatment of hBMSC cells with a Akt inhibitor Triciribine, the above indexes showed reverse changes (P<0.05). Furthermore, compared with HG-CM group, the cell viability and migration ability (P<0.05) of HUVECs in HG+E2-CM group were increased significantly (P<0.05), and the proportion of apoptosis was decreased (P<0.05). While compared with HG+E2-CM group, the cell viability and migration ability of HUVECs in HG+E2+Triciribine-CM group were decreased (P<0.05), and the proportion of apoptosis was increased (P<0.05). Conclusion: Estrogen may promote the secretion of NO, VEGF and IL-8 by activating the Akt/eNOS signaling pathway of hBMSC cells, increase the cell viability and migration ability of HUVECs and inhibit the occurrence of apoptosis, play a protective role against the injury of HUVECs induced by HG condition.

The prevalence of chronic kidney disease(CKD) increases year by year and has become a highly prevalent disease, seriously affecting the quality of life of patients and bringing heavy family burden. There are many diseases causing CKD, including va-rious primary and secondary glomerulonephritis, renal tubular injury, and renal vascular lesions. Although routine medical treatment for CKD can alleviate the clinical symptoms to a certain extent, it is sometimes difficult to prevent the progression of CKD. Traditional Chinese medicine(TCM) is advantageous in high safety, few adverse reactions, and definite clinical efficacy in the treatment of CKD. The active components contained can play a synergistic effect through multiple pathways and multiple targets to delay disease progression, but its mechanism of action has not been fully elucidated. As revealed by the literature in this field in China and abroad, abnormal mitophagy is a common feature of the pathogenesis of CKD of different types. In recent years, a large number of studies have proved that the regulation of mitophagy through the PINK1/Parkin signaling pathway and mitophagy receptor pathway could delay the progression of CKD and protect renal function. Therefore, the regulation of mitophagy by TCM in the prevention and treatment of CKD through related pathways has become a potential therapeutic target in recent years. This paper reviewed the research articles on the definite efficacy of TCM in preventing and treating CKD by regulating mitophagy through relevant pathways to provide new targets and stra-tegies for preventing and treating CKD and delaying their entry into end-stage renal diseases.

A passive air sampler was used to monitor the concentration and contamination profile of 18 polychlorinated biphenyls (PCBs) in the atmosphere over the urban and industrial area of Gaolan, a city in northwest China, during the non-heating and heating seasons of 2018, and the sources, pollutant transport, and the health risks of PCB exposure were analyzed and assessed using principle component analysis, trajectory modeling, and inhalation exposure modeling. The atmospheric concentration in the study area ranged from 110.2 to 429.9 pg·m -3 , and the highest average concentration was found at the industrial estate. Tetra-PCBs and penta-PCBs were the dominant homologue groups, and the percentage of tetra-PCBs increased in the heating season. Combustion and industrial thermal processes, PCB-containing electrical equipment, and the combined source of volatilization from paint, combustion, and industrial thermal processes were considered to be the main sources, and the source of combustion and industrial thermal processes contributed the largest proportion of PCBs at 40.8%. Largely, the emission of UP-PCBs would significantly influence PCB pollution in the study area. Trajectory analysis results illustrated that PCBs emitted from sources in the study area would be transmitted to Lanzhou City atmospherically; local pollution would be the main source of PCBs contamination in the study area during the non-heating season, while the atmospheric input of PCBs transmitted from the northwest region would be another source during the heating season. Health risk analysis showed that the non-cancer risk of PCBs exposure was low in all age groups; however, lifetime cancer risks exceeded 10 -6 . PCBs emitted from combustion and industrial thermal processes sources would have a strong impact on resident exposure to PCBs, and adverse health effects would be caused due to long-term inhalation exposure of the inhabitants to PCBs contamination in the study area.

Objective: To evaluate the clinical effects of plasmakinetic enucleation of the prostate (PKERP) and holmium laser enucleation of the prostate (HoLEP) in the treatment of BPH., Methods: We retrospectively analyzed the clinical data on 78 BPH patients treated by PKERP (n = 38) or HoLEP (n = 40) from January 2016 to October 2017. We recorded the operation time, intraoperative hemoglobin level, catheter-indwelling time, bladder irrigation time, hospital stay, 6-month postoperative IPSS, quality of life (QOL), maximum urinary flow rate (Qmax), postvoid residual urine (PVR), PSA level, International Index of Erectile Function (IIEF) and postoperative complications, and compared the obtained parameters between the two groups and some of them with the baseline., Results: In comparison with the baseline, both the PKERP and HoLEP groups showed statistically significant differences at 6 months after surgery in the QOL score (4.82 ± 0.56 and 4.70 ± 0.67 vs 2.44 ± 0.69 and 2.92 ± 0.49, P < 0.01), IPSS (19.52 ± 4.96 and 19.44 ± 4.08 vs 9.56 ± 2.5 and 9.81 ± 2.5, P < 0.01), Qmax (［4.54 ± 1.86］ and ［4.42 ± 2.89］ ml/s vs ［17.72 ± 3.46］ and ［17.27 ± 4.42］ ml/s, P < 0.01), and PVR (［83.73±55.33］ and ［109.65 ± 89.58］ ml vs ［19.93 ± 11.07］ and ［18.31 ± 15.03］ ml, P < 0.01). Statistically significant differences were also found between the PKERP and HoLEP groups in the reduced hemoglobin level (［21.04 ± 16.96］ vs ［7.88 ± 6.65］ g/dl, P = 0.01), catheter-indwelling time (［7.67 ± 2.27］ vs ［3.93 ± 2.18］ d, P = 0.01), bladder irrigation time (［1.67 ± 0.62］ vs ［1.3 ± 0.54］ d, P = 0.05), hospital stay (［4.22 ± 1.55］ vs ［3.26 ± 0.9］ d, P = 0.01), and 6-month postoperative QOL score (［2.44 ± 0.69］ vs ［2.92 ± 0.49］, P = 0.05), but not in the other parameters., Conclusions: Both PKERP and HoLEP are safe and effective for the treatment of BPH, the former more feasible in primary hospitals, while the latter with the advantages of less bleeding, shorter catheterization and hospital stay, and higher 6-month postoperative QOL score.

Objective: To explore the relevance between the expression of C-MYC gene and protein of patients with T lymphoblastic lymphoma and leukemia(T-LBL/ALL) and its effect on the prognosis., Methods: Paraffin specimens from 60 cases of T-LBL/ALL with detailed follow-up during May 2005 to May 2016 were selected as study group; at same time 20 cases of reactive hyperplasia (RH) of lymphonuedes were selected as control group. The immunohistochemical EnVision method was used to mark the terminal deoxynucleotidyl transferase (TDT), myeloperoxidase (MPO), Ki-67 and C-MYC immune tissue., Results: C-MYC gene rupture and copy number increase did not occur in 20 cases of RH.The expression of C-MYC protein did not correlate with C-MYC gene copy number increase. The expression rate of C-MYC protein was 66.7% (40/60), and 20 cases of lymph node RH was all negative (0/20), as compared with the positive expression rate of protein C-MYC, the difference was statistically significant (P<0.05). The Ki-67 positive index and mediastinal bloadening had influence on the expression of C-MYC protein (P<0.05), the sex, primary site, symptoms, age, AnnArbor stage and lactate dehydrogenase (LDH) level and bone marrow involvement have no influence on it, there was no statistically significant difference (P>0.05). The 8q24 chromosome breakage occurred in 6 cases (10%), and the number of copies increased in 11 cases (18.3%). C-MYC gene copy number increase and C-MYC gene rupture in a total 20 cases of reactive hyperplasia of lymph nodes did not occur., Conclusion: C-MYC gene may play an important role on the development of T-LBL/ALL. It can be an independent prognosis factor.

The waste water containing dyes is difficult to be biochemically treated because of its deep color. Adsorption becomes an important treatment method for this kind of waste water. The iron organic framework was rapidly synthesized at room temperature, and characterized by IR and XRD. Adsorption properties of the materials were tested using four anonic dyes solutions. It was found that the iron organic framework could be formed rapidly, with higher surface area and pore volumes. The pH value of zero point charge was 3.7. The adsorption experiments showed that the iron organic material could remove more dyes in acid solution. The dye adsorption capacity increased with increasing dye concentration. These adsorption data fitted well with Langmuir thermoadsorption equation. The calculated parameter from Langmuir adsorption indicated that the adsorption process could be performed easily. The second order kinetic equation could describe the adsorption data. In addition, the structure of dyes could affect the adsorption process. The metal complex dyes could be quickly removed.

Objective: To investigate the correlation between the lumbar bone marrow fat and abdominal fat., Methods: A total of 68 individuals (32 men and 36 women, aged 21-74 years with a median of 49.5 years) were included in this study. All the subjects underwent spectroscopic examination of the third lumber vertebra with the single voxel method on a 1.5T MR scanner to measure the fat fraction (FF%). Quantitative CT was also performed for measurement of the abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The measurements were compared between subjects aged ≥50 years and those below 50 years, respectively,in male or female subjects., Results: In male subjects, BMI, FF%, VAT or SAT showed no significant differences between the two age groups (P>0.05), and FF% was not correlated with BMI, VAT or SAT (r=0.109, 0.034, 0.066, respectively; P>0.05). In the female subjects, BMI, FF%, VAT and SAT differed significantly between the two age groups (P<0.05), and in ≥50 years group, FF% showed a positive correlation with VAT (r=0.499, P<0.05) but was not correlated with SAT (r=0.221, P>0.05); in<50 years group, FF% was not correlated with VAT or SAT (r=0.076, -0.067, respectively; P>0.05)., Conclusion: FF% is positively correlated with VAT in female subjects aged beyond 50 years, but is not correlated with VAT or SAT in male subjects or in younger female subjects.

Nitrogen fertilizer is necessary to improve yield and quality of lettuce. Spectroscopy is one of the most effective techniques used to detect crop nitrogen content. In this study, canopy reflectance spectra were acquired under five levels of nitrogen, and then were Savitzky-Golay smoothed, the first-order derivative spectra were calculated from the smoothed spectra to eliminate noise effects. Backward interval partial least squares (BiPLS), genetic algorithm (GA) and successive projections algorithm (SPA) were combined to select the efficient wavelengths. The number of variables was decreased from 2,151 to 8. The optimal intervals or variables were used to build multivariable linear regression (MLR) model, radial basis function neural network (RBFNN) models and extreme learning machine (ELM) models. This work proved that the results of BiPLS-GA-SPA-ELM model was superior to others with RMSEC was 0.241 6%, Rc was 0.934 6, RMSEP was 0.284 2% and Rp was 0.921 8. Our research results may provide a foundation for nutrition regulation and developing instrument.