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Federated learning can effectively ensure the privacy and security of data because it trains data locally on the client.The study of federal learning has made great progress.However,due to the existence of non-independent and identically distributed data,unbalanced data amount and data type,the client will inevitably have problems such as lack of accuracy and low training efficiency when using local data for training.In order to deal with the problem that the federal learning efficiency is reduced due to the difference of the federal learning background,this paper proposes an efficient federated learning scheme based on background optimization to improve the accuracy of the local model in the terminal device,so as to reduce the communication cost and improve the training efficiency of the whole model.Specifically,the first device and the second device are selected according to the diffe-rence in accuracy in different environments,and the irrelevance between the first device model and the global model (hereafter we collectively refer to as the difference value) is taken as the standard difference value.Whether the second device uploads the local model is determined by the value of the difference between the second device and the first device.Experimental results show that compared with the traditional federated learning,the proposed scheme performs better than the federated average algorithm in common federated learning scenarios,and improves the accuracy by about 7.5% in the MINIST data sets.In the CIFAR-10 data set,accuracy improves by about 10%.

Cold spray, as a low - temperature solid - state forming technology, has a series of advantages over other deposition methods, such as little heat influence towards substrate, minimized particle oxidation, and high deposition efficiency, and therefore it has been widely used for metallic protective coating fabrication, component repair and additive manufacturing. In this work, the characteristics of cold spray were firstly demonstrated from three aspects including cold spraying system, materials, and process. Next, the research progress of cold spraying technology on powder materials design, coating bonding mechanism, and coating microstructure and performance control in recent years were presented. Then, the application of cold spraying technology in the field of foreign naval ships and warships was described in detail. Finally, the research and application of cold spraying technology in the field of naval ships and warships in China were briefly described, and its future development direction was prospected in order to improve the corrosion protection and maintenance support ability of naval ships and warships equipment in China.

To investigate the early mechanical strength and water penetration resistance of tunnel shotcrete under full-section construction method, a case study is conducted on an inclined shaft of the Zhengzhou-Wanzhou railway constructed by full-section method. Then, the adaptation between designed strength grade of shotcrete and full-section construction method is analyzed via concrete performance test, actual construction verification, and hydration microscopic analysis. The test results reveal the following: (1) The early age mechanical strength of shotcrete per hour develops faster than molded concrete. The eight-hour compressive strength of shotcrete increases from 3.2 to 7.0 MPa when increasing the designed strength grade from C25 to C40. (2) The water penetration resistance of shotcrete is positively and linearly related to 28-day compressive strength. (3) The magnitude and compactness of plate-like C-S-H in the C35 shotcrete perform better than C25 shotcrete, which can reduce the porosity of hydration microstructure induced by rod-like ettringite crystal, thus increasing 28-day compressive strength and enhancing water penetration resistance. (4) The eight-hour mechanical strength of primary support structure after applying C35 high-performance shotcrete reaches 6.0 MPa, effectively reducing the early and accumulated displacement deformation of primary support. [ABSTRACT FROM AUTHOR]

Longtime behavior of the Kirchhoff plate equations with locally distributed internal damping is studied. The equation is equipped with either homogeneous Dirichlet boundary conditions of zero order and second order, or Robin boundary conditions of first order and third order. Under some assumptions on the damping, it is shown that sufficiently smooth solutions of the equation decay logarithmically. [ABSTRACT FROM AUTHOR]

Graphene, as a rising star in materials science, is intensively studied in Li-ion batteries and supercapacitors, owing to its unique structure and excellent properties. The research status of the application of graphene in energy storage field was disscussed and the future development trend was predicted, and therefore to enhance the understanding of the structure-performance relationship of graphene and also the application of graphene in this field. Firstly, the application of graphene in cathode and anode of Li-ion battery, and the application of graphene in electrical double-layer capacitor and pseudo-capacitor were introduced. Secondly, the challenges of graphene in electrical double-layer capacitor were discussed and the ideal structure of graphene applied to electrical double-layer capacitor was proposed. Finally, the "three steps" to realize the commercial application of graphene-based electrical double-layer capacitor were put forward.

To investigate the chest computed tomography (CT) manifestations and dynamic changes of coronavirus disease 2019 (COVID-19) in the patients younger than 18 years old infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, and to provide a basis for determining the chest CT changes and efficacy of COVID-19 caused by Omicron virus variant in patients younger than 18 years old. Methods The clinical and imaging data of 30 cases of patients younger than 18 years old infected with COVID-19 Omicron variant, who admitted to the Third People's Hospital of Shenzhen from February 11 to March 26, 2022 were collected and retrospectively analyzed. The clinical manifestations, imaging features and dynamic changes of lesions were summarized. Results A total of 41 intrapulmonary lesions in 30 patients with COVID-19 caused by SARS-CoV-2 Omicron variant. The main manifestations were patchy or nodular ground-glass opacities and/or consolidation, with focal subpleural distribution, lesions mainly occur in the right lung (70.73%, 29/41). There were 42 lesion morphologies, with 22 (52.38%) striped shadows and 16 (38.10%) nodular shadows, with small lamellar and patchy shadows predominating. There were 36 lesion density variations, with ground glass shadows being the most common, with a total of 24 ground glass shadows (66.66%) in each lobe of the lung, and also 6 consolidation lesions (16.67%) and 6 mixed ground glass opacity and consolidation lesions (16.67%). With the progression of the disease, lesions gradually enlarged, appeared on the 2nd day (312.93 mm3), peaked on the 9th day (1 837.18 mm3). The average absorption time of the lesions was (16±3) days, and there was no significant difference between the absorption time of patchy and nodular lesions (ground glass and /or consolidation) (t=0.853, P>0.05). The lesions showed focal ground-glass opacity in the early stage, 77.78% lesions were absorbed after treatment in the late stage. Inflammatory nodules were absorbed slowly (9-19 days), without residual fibrotic changes. Conclusions The imaging manifestations of COVID-19 in patients younger than 18 years old infected with SARS-CoV-2 Omicron variant have certain characteristics, showed patchy or nodular ground glass opacities and/or consolidation, mainly distributed in the subpleural area, with small and few lesions and slow change, didn't remain fibrosis. Being familiar with its clinical and imaging manifestations can assist in early diagnosis, but confirming the diagnosis requires a combination of epidemiological history, clinical symptoms, SARS-CoV-2 nucleic acid and radiological manifestations. [ABSTRACT FROM AUTHOR]

HACS/PVA/GO biodegradable mulch film was prepared by casting method with high amylose corn starch (HACS), polyvinyl alcohol (PVA) and graphene oxide (GO) as the main raw materials. The degradation rate, mechanical properties and light transmittance of the mulch film with different degradation cycles were tested by simulating soil degradation experiment. The results show that the degradation rate of the film reaches (58.35±4.84)% after 12 weeks of degradation. The molecular structure of the film changes during the degradation process, and the decomposition of HACS and PVA molecules lead to the decrease of crystallinity. During the degradation process, the surface and cross-sectional structure of the film are obviously damaged. After 4 weeks of degradation, the tensile strength of the film is decreased from (10.12±0.23) MPa to (2.88±0.71) MPa, the elongation at break is decreased from (205.72±3.01)% to (58.37±7.31)%, and light transmittance is decreased from (84.43±2.96)% to (18.31±4.32)%. [ABSTRACT FROM AUTHOR]

The paper introduced spray method, working principle, composition and characteristics of a spray system of hydraulic support of thin coal seam. The spray system of hydraulic support adopts method of high pressure spray method and can control dust around hydraulic support of thin coal seam in coal face effectively. The spray device is set in roof timber in order to save space, which resolves the problem that spary device occupies walkway and cross section of ventilation. The system takes full advantages of electro hydraulic controller and has high automation degree.

In order to solve the problems of nutrient absorption and accumulation and provide theoretical basis for rational amount of calcium fertilization of peanut in saline land, the effects of calcium fertilizer application on absorption and accumulation of nutrients including nitrogen, phosphorus, potassium, calcium and magnesium in peanut under salt stress were examined. Using 'Huayu 25' as experimental material, four Ca levels [T1(0), T2(75), T3(150) and T4(225) kg µ hm-2 CaO] were set under 0.3% salt stress in a pot experiment. The results showed that nutrient contents in peanut followed the order of nitrogen > potassium > calcium > phosphorus > magnesium. At the seedling stage, leaves were the absorption center of nitrogen and calcium, while stems were the center of phosphorus, potassium and magnesium, with nearly half of nutrient accumulation being distributed in the corresponding growth center. At mature stage, the absorption centers of nitrogen, phosphorus and potassium were transferred to pod. The accumulation of nitrogen and phosphorus in seed kernel reached to 72.3%-78.9%. The absorption centers of calcium and magnesium was still in the leaves and stems, with a distribution ratio of 49.8% and 32.6%, respectively. Salt stress significantly inhibited nutrient absorption and distribution in peanut, Especially decreased the nitrogen accumulation in leaves and seed kernels. However, salt stress increased the magnesium accumulation in pod. Exogenous calcium application had significant positive effect on absorption and accumulation of nitrogen, phosphorus, calcium and magnesium in different organs of peanut under salt stress. It had significant adjustment on phosphorus accumulation in seed kernel, which was increased by more than 50%. Appropriate calcium content could significantly promote the peanut nutrient absorption and accumulation under salt stress and improve the distribution ratio of nitrogen, phosphorus, potassium in mature pods of peanut. According to the responses of nutrient absorption and distribution, the optimized application amount for calcium fertilizer under 0.3% salt stress was 150 kg µ hm-2 CaO. [ABSTRACT FROM AUTHOR]

Plant roots have considerable impact on the shear properties of soil, but to date the underlying mechanisms have been poorly quantified. In order to understand the fundamental mechanisms of soil reinforcement by Hedysarum scoparium roots and reduce the cost of the testing and relieve the destruction of environment due to digging roots, five-year plant specimens were collected from the Gaoshawo forest field (Northwest China) by in-situ excavation in this study. The shear properties of root-soil composite of Hedysarum scoparium were studied by the finite-element numerical simulation software. The influence of the root area ratio (RAR) and the vertical load on the shear strength of root-soil composite of Hedysarum scoparium was discussed in this study. The laboratory direct shear test was used to prove the reliability of the numerical simulation under the condition of the 7% soil moisture content and the RAR of 0.0034. The results showed that the shear strength of roots-soil composite conformed to the Mohr-Coulomb's yield criterion and the roots of Hedysarum scoparium could notably enhance the soil shear strength. It was also found that a strong correlation between the RAR and the root apparent cohesion. The root apparent cohesion increased with the increasing of the RAR according to a linear function (R2>0.9). Under the same RAR, the capacity of soil reinforcement by the roots was weakened with the increase of the vertical load, and a logarithmic function (R2>0.9) could be used to describe the relationship between the shear strength growth rate of root-soil composite to pure soil and the vertical load. Under the same vertical load, the growth rate of shear strength of root-soil composite to pure soil decreased linearly with the decreasing of the RAR (R2>0.9). The roots of Hedysarum scoparium played an obvious role to reinforce soil under the low vertical loads. The results of the study indicated that the peak value of the shear stress of root-soil composite of Hedysarum scoparium appeared later compared with that of pure soil. It implied that the root reinforcement did not occur until the significant plastic deformation appeared. Therefore, the roots seemed to have little influence on soil reinforcement for small strains acting on soil-root composite. The numerical simulation results were consistent with the results of laboratory test (the maximum relative error was only 4.26%). It was found that an increase in the vertical load of root-soil composite of Hedysarum scoparium made the contribution of roots to the shear strength increment of root-soil composite decrease. The differences of the cohesion stress and friction angle of root-soil composite of Hedysarum scoparium were only 0.6179 kPa and 0.0039° respectively based on the fitting equation between the vertical load and the shear strength. The fitting equation was developed from the numerical simulation and the laboratory direct shear test results. This paper presented a numerical simulation model capable of simulating the direct shear of root-soil composite of Hedysarum scoparium. The numerical simulation results could serve as the basis and reference for further studies on shear characteristics of root-soil composite. [ABSTRACT FROM AUTHOR]

Hedysarum scoparium and Salix psammophila have obvious effect on the fixation of mobile and semi-mobile dunes in the Mu Us Desert. In order to explore the friction characteristics between root and soil, 5-year-old Hedysarum scoparium and Salix psammophila roots were measured in the laboratory. The influences of different conditions such as species, soil moisture and vertical load were examined by using direct shear friction tests in the study. The finite element software was used to simulate the process of the laboratory experiments. The results showed that the cohesion stress of the root-soil interface of Hedysarum scoparium and Salix psammophila had a significant difference (P < 0.05). However, there was no significant difference between Hedysarum scoparium root-soil interface and soil-soil interface (P > 0.05). The cohesion stress of the root-soil interface of Salix psammophila and soil-soil interface had a significant difference (P < 0.05). The cohesion stress of the root-soil interface of Hedysarum scoparium ((1.51±0.65) kPa) was higher than that of Salix psammophila ((-0.92±0.50) kPa), and the cohesion stress of soil-soil interface ((3.22±0.55)kPa) was also higher than that of Salix psammophila. The friction angle of the root-soil interface of Hedysarum scoparium had a significant difference with Salix psammophila (P < 0.05) and it also had a significant difference with soil-soil interface (P < 0.05). However, there was no significant difference between Salix psammophila root-soil interface and soil-soil interface (P > 0.05). The friction angle of the root-soil interface of Hedysarum scoparium ((31.00±0.14)°) was higher than that of soil-soil interface ((30.30±0.25)°) and Salix psammophila((30.20±0.17)°). There was a significant difference between the cohesion stress and the friction angle of the root soil interface (P < 0.05) under 2% (dry season) and 22% (rainy season) soil moisture. However, there was no significant difference under 7%-17% soil moisture (P > 0.05). The cohesion stress of 2% soil moisture ((0.0021±0.34) kPa) was lower than that of 22% soil moisture ((3.16±0.57) kPa). The friction angle of 2% soil moisture ((29.80±0.38)°) was lower than that of 22% soil moisture ((30.92±0.59)°). The relationship between vertical load and shear strength of the root-soil interface obeyed the Mohr-Coulomb theory and the constitutive relation was hyperbola. The maximum relative error of the shear strength simulated by the finite element software was 9.54%. The results of the study indicated that the improvement of shear strength of the root-soil composite was not related to the cohesion stress but related to the friction angle. The shear strength of the root-soil interface of Hedysarum scoparium was stronger than that of soil-soil interface and Salix psammophila (P < 0.01). The change of soil moisture had a similar influence on the cohesion stress and the friction angle of the root-soil interface. The capacity of improving shear strength of soil by root reinforcement was significantly affected by the dry and rainy season (P < 0.05). The process of the direct shear friction tests of root-soil and soil-soil interface could be simulated by the finite element model established in the study. The simulation results were consistent with the laboratory tests. The results of this research can serve as a basis for the further studies on the friction characteristics of root-soil interface and root reinforcement. This study also can provide a reference for the selection of windbreak and sand-fixation tree species. [ABSTRACT FROM AUTHOR]

Bacillus mucilaginosus is a kind of heterotrophic aerobic bacteria, which can decompose phosphorus and potassium in soil and silicate minerals, and is widely used in microbial fertilizers. The bacteria is cultured by liquid fermentation and followed by peat adsorption, but the effective number of viable microorganisms and spore rate were lower. Therefore, it is important to identify how to increase the number of viable cells and spore rate with optimized fermentation pattern and condition of Bacillus mucilaginosus. In this study, a strain named YA-07 was isolated from apple orchard soil in Luochuan County of Shannxi Province, which was identified as Bacillus Mucilaginosus through the morphological, physiological and biochemical experiments and the sequence of 16s rDNA. By single factor, and orthogonal experiments, a kind of solid-state fermentation condition, which could produce high density of effective living bacterium and high rate of spore was established. The Results showed that the medium that can make YA-07 produce a large number of effective number of living bacterium, and high spore rate can be divided into 500 mL bottles of peat 50 g, starch 3%, peptone 3%, without inorganic salts and trace elements. At 30°C pH 7.0, 10% inoculation amount, and 144 h cultivation time, the effective number of living bacterium of YA-07 can reach 1.58X109 cfu/g, and the spore rate can reach 91.3%. In this study, the effective number of viable cells and rate of Bacillus mucilaginosus spores were increased by solid fermentation, which not only improved the quality of microbial fertilizer, but also reduced the environmental pollution, so it is of important significance for promoting the development of green agriculture in China. [ABSTRACT FROM AUTHOR]

To evaluate the feasibility of hybrid process of coagulation, sedimentation and immersed ultrafiltration (UF) for the drinking water treatment from Bei River source water, pilot study was performed in terms of pollutants removal and membrane fouling. The performance of the hybrid UF process was also compared with that of the conventional process in the full-scale drinking water treatment plant. Results showed that in the conventional treatment process, there was still 0.176 NTU of turbidity in the sand-filtration effluent on average; while it was only 0.080 NTU in the hybrid UF process. The removal efficiencies of conventional treatment process for CODMn and UV254 were 47.5% and 42.3%, respectively, which were slightly lower than the 50.6% and 44.0% achieved by the hybrid UF process. As for the membrane fouling, it was shown that the trans-membrane pressure (PTM) would increase rapidly when direct UF of raw water was carried out. However, in the hybrid UF process, due to the pre-removal of membrane foulants by coagulation and sedimentation, the PTM development rate became much lower; and stable operation of the UF could be achieved. It is demonstrated that the hybrid UF process can improve the security of drinking water supply. [ABSTRACT FROM AUTHOR]

A pilot-scale membrane adsorption bioreactor (MABR) was carried out for the drinking water treatment from Dong River water with coagulation-sedimentation as pre-treatment. During the experiments, the MABR exhibited much higher capacity for organic matter removal as compared with the conventional sand-filtration and ultra-filtration alone, with the average removal efficiencies of 72.4% and 89.1% for CODMn and UV254, respectively. During the stable operation period after start-up, the MABR also achieved excellent removal for the influent NH3-N and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. -N, the effluent concentrations were maintained below O.2 mg/L and O.05 mg/L, respectively. In the investigation, the membrane in MABR was operated under the conditions of constant flux (20 L./( m² ⋅ h) ), continuous aeration ( 12.5 m³/( m² ⋅ h), calculated based on the bottom area of the membrane tank), and backwashing for 5 rain after every 8 h of filtration. Under these conditions, obvious membrane fouling was observed for the membrane, with the average trans-membrane pressure development rate of 0.51 kPa/d. To mitigate membrane fouling and to decrease the chemical cleaning time, it is required to further optimize relevant operating parameters of the membrane in MABR. [ABSTRACT FROM AUTHOR]

To evaluate the suitable sludge retention time (SR) in submerged membrane bio reactor (SOMBER) for drinking water treatment, two Mrs under the SR of 80 d and 20 d were run in parallel and compared in terms of the effectiveness for treating polluted raw water. The results showed that under the SR of 80 d, the removal efficiencies of SOMBER for DOC, UV254, TO, CODMN were 19.6% , 13.4%, 27.7% and 30. 7%, while those under the SR of 20 d were 21.2%, 13.2%, 29. 2% and 32.7% , respectively. Furthermore, both of the Mrs achieved over 96% of removal for influent NH3 - N. However, when the short SR (20 d) was employed, the development rate of Trans - membrane pressure in SOMBER was lower than that under hg SR (80 d). Therefore, the reduction of SR from 80 d to 20 d would not affect the effectiveness of SOMBER for treating polluted raw water, but mitigate the membrane fouling in SOMBER. With the short SR, it would be possible to dose powdered activated carbon directly in the SOMBER, in which the sludge withdrawal could be performed periodically, to maintain the sludge concentration in suitable range. [ABSTRACT FROM AUTHOR]

To produce high quality drinking water more effeciently, a submerged membrane adsorption bioreactor ( MABR) was evaluated for enhanced removal of organic matter from contaminated raw water. The results showed that the MABR was able to decrease influent TOC, CODMn, DOC and UV254, as well as BDOC and AOC by 41. 3% , 59. 4% , 36. 7% , 53. 5% , 67. 9% and 44. 0% , respectively, when powdered activated carbon (PAC) was dosed in the reactor at 8 mg/L. In the MABR, physical separation by the membrane, biodegradation by microorganism and adsorption by PAC were identified to jointly contribute to the removal of dissolved organic matter, with the respective contribution of 11. 1% , 7. 6% and 18. 0% in terms of DOC removal. However, enhanced separation effect on dissolved organic matter in the mixed liquor was observed for the membrane in MABR, which was attributed to a dynamic sludge layer formed on the membrane surface based on microscopic analysis. Taking into account of the short hydraulic retention time (0. 5 h) , MABR technology may be both technically and economically promising for application in drinking water treatment. [ABSTRACT FROM AUTHOR]

Using the hybrid chemical and biological sludges as raw material, the adsorbent was prepared by chemically activating with 18. 0 mol/L H2SO in the mass ratio of 1 : 3, and thereafter pyrolyzing at 550 °C for 1 h. The physical and chemical characteristics of the hybrid sludge-derived adsorbent were examined in terms of the surface physical morphology, the specific surface area and pore structure, the aluminum and iron contents, and element composition. Furthermore, the adsorption effect of the adsorbent for organic substances in wastewater was also investigated. The results indicated that the adsorption capacity of the sludge-derived adsorbent for UVzs was lower than that of a commercial activated carbon (AC), while its capacity of adsorbing COD was higher than that of the commercial AC. Further study showed that the sludge-originated adsorbent could reduce the polymeric ferric aluminous chloride (PFAC) dosage when it was reused in chemically enhanced primary treatment. With the simultaneous dosing of 15 mg/L of PFAC and 0. 3 g/L of the adsorbent, the removal efficiencies of UVzs and COD reached to 26. 1% and 61.6% , respectively. The coagulant dosage could be reduce to about 50% through the addition of the adsorbent to achieve similar removal efficiencies of UV254 and COD. [ABSTRACT FROM AUTHOR]

In order to investigate the correlation between algae propagation and physico-chemical factors for reservoir water, the algae propagation was modelled and the factors were monitored under the microcosm envi ronment for building regression equations. The linear matrix based on the biomass of anabaena(ACD) , micro cystis(ACM) and algae(AC) in moderate eutrophic situation was built. Results showed that the reservoir is phosphorous-limited and relative to total phosphorous (TP) and temperature. The prediction equations based on TP and temperature can predict algae concentration variations. The prediction equations bulit under microcosm conditions can help water plants predict algae concentrations and adjust water treatment processes according to the equations' results. [ABSTRACT FROM AUTHOR]

NbN thin films were deposited at room temperature with reactive magnetron sputtering method at different N2 partial pressure. X-ray diffraction analysis, transmission electron microscopy and atomic force microscopy were employed to characterize their phases, microstructure and surface morphology. Their microhardness and elastic modulus were evaluated using a microhardness tester and the effect of N2 partial pressure on the phase formation, microstructure and mechanical properties of NbN thin films was investigated. The results show that there is an obvious effect of N2 partial pressure on the deposition rate, phases, hardness and elastic modulus of magnetroned NbN films : at a low N2 partial pressure, the deposition rate is higher and hcp β-Nb2N and fcc δ-NbN coexist in NbN films ; with the increase of N2 pressure, the films are single-phase fcc δ-NbN and accordingly, the hardness and modulus reach peak values of 36.6 GPa and 457 GPa respectively; with a further increase of N2 partial pressure, there are fcc δ-NbN and hcp ε-NbN in NbN films and the hardness and modulus of films decrease. [ABSTRACT FROM AUTHOR]

Urban traffic is closely related to the daily life of the public,and air pollution in the traffic microenvironment has become a public health problem that cannot be ignored.This paper reviews the comparative studies of air pollutant exposure levels among different modes of transportation in multiple cities in China.By comparing the exposure levels of pollutants among different modes of transportation,this paper provides a reference for protecting the health of the public in daily transportation and selecting targeted control measures.

Objective: Invent a simulator which provides a simulation of heart rate and respiratory rate to the intelligent sleep monitoring devices based on precision pressure sensors., Methods: The simulator was composed of control part and simulated silicone doll. The simulated silicone doll contains heartbeat simulator and breathing simulation airbag. Heartbeat and breathing combination pressure signal can be produced according to frequency set values. Frequencies of pressure signal of the simulator were compared with the monitoring results of intelligent sleep monitoring devices with known accuracy to verify the frequency accuracy of pressure signal of the simulator. Verified the repeatability and stability of the simulator with a stopwatch., Results: The heart rate of the simulator was with in ±2 beats per minute of the monitoring results of intelligent sleep monitoring devices and the respiratory rate of the simulator was with in ±2 times per minute of the monitoring results. The repeatability and stability of the simulator was better than ±5% according to results with a stopwatch., Conclusions: It's practicable to use the simulator which provides a simulation of heart rate and respiratory rate to the accuracy test of the intelligent sleep monitoring devices based on precision pressure sensor.

Objective To explore the overall level,distribution characteristics,and differences in household fine particulate matter (PM 2.5 ) pollution caused by fuel burning in urban and rural areas in China. Methods The relevant articles published from 1991 to 2021 were retrieved and included in this study.The data including the average concentration of household PM 2.5 and urban and rural areas were extracted,and the stoves and fuel types were reclassified.The average concentration of PM 2.5 in different areas was calculated and analyzed by nonparametric test. Results The average household PM 2.5 concentration in China was (178.81±249.91) μg/m 3 .The mean household PM 2.5 concentration was higher in rural areas than in urban areas[(206.08±279.40) μg/m 3 vs. (110.63±131.16) μg/m 3 ; Z =-5.45, P <0.001] and higher in northern areas than in southern areas[(224.27±301.66) μg/m 3 vs. (130.11±140.61) μg/m 3 ; Z =-2.38, P =0.017].The north-south difference in household PM 2.5 concentration was more significant in rural areas than in urban areas[(324.19±367.94) μg/m 3 vs. (141.20±151.05) μg/m 3 , χ 2 =-5.06, P <0.001].The PM 2.5 pollution level showed differences between urban and rural households using different fuel types ( χ 2 =92.85, P <0.001),stove types ( χ 2 =74.42, P <0.001),and whether they were heating ( Z =-4.43, P <0.001).Specifically,rural households mainly used solid fuels (manure,charcoal,coal) and traditional or improved stoves,while urban households mainly used clean fuels (gas) and clean stoves.The PM 2.5 concentrations in heated households were higher than those in non-heated households in both rural and urban areas ( Z =-4.43, P <0.001). Conclusions The household PM 2.5 pollution caused by fuel combustion in China remains a high level.The PM 2.5 concentration shows a significant difference between urban and rural households,and the PM 2.5 pollution is more serious in rural households.The difference in the household PM 2.5 concentration between urban and rural areas is more significant in northern China.PM 2.5 pollution in the households using solid fuel,traditional stoves,and heating is serious,and thus targeted measures should be taken to control PM 2.5 pollution in these households.

The present study aimed to explore the chemical constituents from the stems and leaves of Cephalotaxus fortunei. Seven lignans were isolated from the 75% ethanol extract of C. fortunei by various chromatographic methods, including silica gel, ODS column chromatography, and HPLC. The structures of the isolated compounds were elucidated according to physicochemical properties and spectral data. Compound 1 is a new lignan named cephalignan A. The known compounds were identified as 8-hydroxy-conidendrine(2), isolariciresinol(3), leptolepisol D(4), diarctigenin(5), dihydrodehydrodiconiferyl alcohol 9'-O-β-D-glucopyranoside(6), and dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside(7). Compounds 2 and 5 were isolated from the Cephalotaxus plant for the first time.

With the implementation of the new policy for coronary stent centralized volume purchasing in China, the blood pressure sensor at the tip of the catheter, as one of the essential medical instruments for the diagnosis and treatment of coronary artery disease, will meet the new development opportunity of the industry, a number of medical device companies will actively participate in the development and registration of the catheter tip blood pressure sensor. As an invasive blood pressure sensor, the catheter tip blood pressure sensor should meet the current effective industry standard YY 0781-2010, however, there are many problems when using YY 0781-2010 as a blood pressure sensor because of the difference of product structure and working mode. In this paper, the problems about "Operation Manual", "electrical performance" and "safety requirement" in the course of carrying out YY 0781- 2010 with the blood pressure sensor on the tip of catheter are discussed and analyzed in detail, hope to provide some inspiration for more research and development enterprises of blood pressure sensors on the tip of catheters and inspectors of medical device testing institutions, also hope to be able to contribute to the high-quality development of blood pressure sensor industry at the tip of the Catheter.

Objective: To investigate the effects of SI-4650, a novel small molecule inhibitor of spermine oxidase (SMO), on the proliferation and epithelial mesenchymal transformation (EMT) of human ovarian cancer SKVO-3 cells as well as its underlying molecular mechanisms. Methods: SKVO-3 cells treated with 0 μmol/L SI-4650 were used as control group, SKVO-3 cells treated with 30, 60 μmol/L SI-4650 were used as experimental group. The effects of SI-4650 on the activity of SMO, the polyamine contents and the cellular reactive oxygen species (ROS) were detected. Cell proliferation, cell cycle and mitochondrial membrane potential change of SKVO-3 cells were tested. The effects of SI-4650 on apoptosis, migration and invasion were investigated. The effects of SI-4650 on Bax, Bcl-2, Caspase3, E-cadherin, N-cadherin, Vimentin, matrix metalloproteinase 2 ( MMP2) and MMP 9 expression levels in SKVO-3 cells were detected. Results: Comparison between blank control group and experimental groups,SI-4650 could improve the content of SI-4650 in SKVO-3 cells. SI-4650 could inhibit the activity of SMO ( P ＜0.01), reduce the ROS ( P ＜0.01)and polyamine content in SKVO-3 cells ( P ＜0.01). Treatment of SKVO-3 cells with SI-4650 inhibited the proliferation (the inhibition rate was 32.27% and 47.31% in experimental groups), caused S-phase cell cycle arrest ( P ＜0.01) and induced apoptosis ( P ＜0.01). The expressions of Bax and c-Caspase3 in SKVO-3 cells were increased ( P ＜0.01),the content of Bcl-2 was decreased ( P ＜0.01), and the mitochondrial membrane potential was decreased ( P ＜0.01), and the number of apoptotic cells was increased(31.41% and 43.51% in experimental groups). At the same time, SI-4650 could change the expression levels of EMT-related factors, increased the expression level of E-cad , decreased the expression levels of N-cad, Vimentin, MMP-2 and MMP-9, and inhibited the migration and invasion of SKVO-3 cells. Conclusion: SI-4650 can effectively inhibit proliferation, invasion and metastasis of human ovarian cancer SKVO-3 cells, and the mechanism may be related to its ability to depress the activity of SMO, interfere polyamine metabolism and induce cell cycle arrest, mitochondrial apoptosis and inhibit EMT. This study reveals potential application of SI-4650 in the treatment of ovarian cancer.

This study investigated the effects and mechanisms of 6-gingerol on adipose tissue insulin resistance in naturally aging rats with glycolipid metabolism disorders. Twenty-seven aging male SD rats were randomly divided into a model group(aged, n=9) and two groups treated with 6-gingerol at 0.05 mg·kg~(-1)(G-L, n=9) and 0.2 mg·kg~(-1)(G-H, n=9). Six young rats were randomly assigned to a normal control group(NC). Rats were treated for seven weeks by gavage. Non-esterified fatty acid(NEFA) and insulin content was determined by enzyme-linked immunosorbent assay(ELISA), and adipose tissue insulin resistance index(Adipo-IR) was calculated. HE staining was used to observe the size of adipocytes in epididymal white adipose tissue(eWAT). The gene and protein expression levels of adiponectin receptor 1(AdipoR1), AMP-activated protein kinase α(AMPKα), phosphorylated AMPK(p-AMPKα~(Thr172)), peroxisome proliferator-activated receptor-γ coactivator-1α(PGC-1α), phosphatidylinositol 3-kinase(PI3 K), protein kinase B(Akt), phosphorylated Akt(p-Akt~(Ser473)), tumor necrosis factor-α(TNF-α), c-Jun N-terminal kinase 1/2(JNK1/2), phosphorylated JNK1/2(p-JNK~(Thr183/Tyr185)), interleukin-1β(IL-1β), and interleukin-6(IL-6) in adiponectin(APN), insulin, and inflammatory factor signaling pathways were detected by Western blot and real-time RCR, respectively. The results showed that 6-gingerol at a high dose could significantly decrease the fasting plasma content of NEFA and insulin and reduce Adipo-IR. Additionally, 6-gingerol at a high dose significantly increased the protein and mRNA expression of APN, AdipoR1, PGC-1α, and PI3 K in eWAT, elevated the relative expression of p-AMPK~(Thr172) and p-Akt~(Ser 473), reduced the protein and mRNA expression of TNF-α, IL-1, and IL-6 in eWAT, and decreased the relative expression of p-JNK1 and p-JNK2. This study reveals that 6-gingerol can improve insulin sensitivity of adipose tissues in aging rats with glycolipid metabolism disorders, and this effect is presumedly achieved by enhancing the PI3 K/Akt signaling pathway, inhibiting adipose tissue inflammation, increasing APN synthesis, enhancing AdipoR1 expression, and activating its downstream AMPK/PGC-1α signaling pathway.

To analyze the feeding habits and trophic level of jellyfish ( Rhopilema esculentum ), Chinese shrimp ( Fenneropenaeus chinesis ), grass shrimp ( Penaeus monodon ), and clam ( Ruditapes philippinarum ), and the food web structure in marine aquaculture pond, we measured the δ 13 C and δ 15 N values of the four species and different feed from May to September in 2017. The average proportional contribution of different feed to the four species were analyzed using the IsoSource linear mixture model. The results showed that zooplankton was the main food source to jellyfish, Engraulis japonicus was the main food source to the two shrimp species, and the phytoplankton, benthic diatoms and dejecta of the two shrimp species were the main food source to the clam. The trophic level of the clam ranged from 2.64 to 2.95, with a mean value of 2.84. The trophic level of jellyfish ranged from 2.78 to 3.27, with a mean value of 3.06. the grass shrimp ranged from 3.03 to 3.54, with a mean value of 3.25. The trophic level of Chinese shrimp ranged from 3.76 to 4.40, with a mean value of 3.95. Results of comprehensive analysis showed that the clam was the primary consumer, jellyfish was the secondary consumer, and shrimps were the predators. Jellyfish filtered the dejecta of the two kinds of prawns and improved water quality of the polyculture pond to a certain extent.

Fourteen current-use pesticides (CUPs) in the surface seawaters of the typical Liaoning sea areas were analyzed using HPLC-MS/MS. The concentrations, distribution, and ecological risks were studied, as well as their source appointments using principal component analysis (PCA). The results revealed that seven types of CUPs were detected in the surface seawaters of the typical Liaoning sea areas. The total concentrations of these CUPs ranged from 16.7 ng·L -1 to 176.1 ng·L -1 . The samples with high concentrations were collected mostly from the estuary, and the concentrations of CUPs in the western Liaodong Bay were generally higher than those in the northeastern Yellow Sea. Atrazine and triadimenol were the predominant CUPs, and their contribution rates accounted for 56.0% and 34.5%, respectively. The PCA results indicated that six types of CUPs might be caused by the runoff from farmlands and the wastewater discharge from the chemical pesticide factory, and fruit planting could be a substantial contributor to the single component acetochlor. Atrazine and acetochlor posed medium-high ecological risks to the microalgae, while all the seven types of CUPs showed relatively lower risks to invertebrates and fish.

With the Liaohe River basin as the research object, the morphology, abundance, and distribution characteristics of micro(meso) plastics of soil in Liaohe River basin were studied based on the density flotation principle and the technique of stereo microscope and micro-FTIR and the significant factors affecting the distribution of the micro(meso)plastics and their potential sources were reasonably speculated. The results indicated that the average abundance of the soil micro(meso)plastic is (145.83±211.46) n·kg -1 . The most abundant types of micro(meso)plastics are debris (46.00%), <1000 μm (39.57%), PP (41.71%), and white (46.86%). Among them, Rayon, PES, and PET micro(meso)plastics are primarily in the shape of fibrous (>85%), PE is mostly in the shape of film and fragments (96.91%), PP is mainly in the shape of fragments (85.62%), and PS is primarily in the shape of foam. Industrial activities (express delivery companies, plastic factories, and clothing factories), agricultural activities (plastic mulch, sewage irrigation, and sludge composting), population density, and sewage treatment plants, etc, may lead to higher levels of micro(meso)plastic abundance in the soil of the study area. Plastic products (pesticide bottles, chemical fertilizer packaging bags, woven bags, and plastic agricultural films), sewage discharge and irrigation, and foam materials used for packaging and decoration are the potential sources of soil micro(meso)plastic in the region.

Objective: To investigate the feasibility of constructing a mouse model of spermatogonial stem cell (SSC) transplant recipient by high-temperature heat stress., Methods: Four-week-old C57BL/6 male mice and B6(Cg)-Tyrc-2J/J coat color gene homozygous mutant male mice were heat-treated at 43 ℃ for an hour in the incubator. The best transplantation time was determined by HE staining, immunohistochemistry and TUNEL and the SSCs were transplanted into the seminiferous tubules of the mice followed by regular observation of the proliferation, differentiation and spermiogenesis of the SSCs in the testis of the recipient mice. Then the recipients were mated with age-matched normal female mice and the epigenetic features of their offspring were observed., Results: After 3－5 days of high-temperature heat stress, the spermatogenic cells in the testicular seminiferous tubules of the recipient mice showed obviously decreased layers, disordered and loose arrangement, massive deletion, significant apoptosis, reduced mesenchymal cells and increased autophagy, which were basically recovered in about 12 days. At 8 weeks after transplantation, the isolated and purified SSCs were differentiated into spermatogenic cells and sperm with genetic function in the testicular seminiferous tubules of the recipient mice, and normal offspring were reproduced after natural mating., Conclusions: High-temperature heat stress can be used as an efficient method for rapid construction of the mouse model of spermatogonial stem cell transplantation recipient.

Base on the data from fishery resources survey carried out in northern coastal waters in Yuhuan in November 2016 (autumn) and April 2017 (spring), we examined the niche and interspecific associations of major nekton by the methods of index of relative importance (IRI), niche breadth, niche overlap, the variance ratio (VR), X 2 -test, association coefficient (AC), Jaccard index (JI), point correlation coefficient (Φ) and Spearman rank correlation index. The ecological niche breadth of Portunus trituberculatus was the largest, with the absolute competitive advantage. The niche breadths of the important economic species Coilia nasus and Octopus variabilis were the smallest, which was at a weak competitive position. The niche overlap of the major nekton species in this area was uneven, possibly caused by the diversity of local environments. Overall interspecific associations indicated that insignificant negative correlation existed among major nekton species. All results of the X 2 -test, association coefficient (AC) and Jaccard index (JI) were consistent with that of overall interspecific associations, which indicated the independent trend among species. The correlation coefficients (Φ) and the Spearman rank correlation index revealed that the positive coupling pairs were more than the negative ones. It was due to the positive association among the other 14 species, caused by the spatial exclusion from large captured individuals of Muraenesox cinereus. According to the Spearman rank correlation and cluster analysis, 15 species could be divided into five ecological groups. The species within one ecological group had similar ecologically adaptable requirements of habitat, while the species from different ecological groups had different living habits and different ecological requirements.

Objective To investigate the change of serum matrix metalloproteinases-9 (MMP-9) expression before,during,and after carotid endarterectomy (CEA) and to investigate the prognostic role of MMP-9. Methods Forty carotid stenosis patients who underwent CEA in the Department of Vascular Surgery,Peking Union Medical College Hospital from February to September 2012 were enrolled in this study. Based on the findings of transcranial doppler monitoring,patients were divided into embolic-positive group and emboli-negative group. Serum samples were obtained from 40 consecutive patients undergoing CEA before operation (pre-op),before de-clamping,30 minutes after de-clamping,and 12 hours after operation (12-h post-op). MMP-9 expression was quantified using enzyme-linked immunosorbent assay and gelatin zymography. Student's t-test and chi-square test were used to compare the differences between these two groups. Results Of these 40 patients,microemboli were detected in 8 patients. The 12-h post-op MMP-9 level was significantly higher than the pre-op level in the emboli-positive group [(904.27±369.47)ng/ml vs. (333.88±126.32) ng/ml,t=4.132,P=0.001].However,there was no difference between pre-op and 12-h post-op MMP-9 levels in the emboli-negative group [(375.83±194.36) ng/ml vs. (472.74±271.21) ng/ml,t=-1.643,P=0.081]. Gelatin zymography also showed higher MMP-9 activity in the emboli-positive group than in the emboli-negative group. Conclusion Serum MMP-9 concentration remarkably increases 12 hours after CEA in patients with microemboli shedding,suggesting MMP-9 may be a potential biomarker for CEA-related cerebral ischemic injury.

This study analyzed the values of δ 13 C and δ 15 N by the application of stable isotope technique from the marine mammals (Phoca largha, Neophocaena asiaorientalis sunameri, Balaenoptera acutorostrata) and major biological species in Dalian marine area based on the animals collected due to stranding and death after bycatch from January, 2008 to June, 2017, and the fisheries resources investigation between autumn, 2016 and spring, 2017 in the same area. The trophic level was then calculated in order to establish the continuous trophic spectrum of the food web in Dalian marine area. The results showed that the value of δ 15 N ranged from 8.0‰ to 14.7‰ and the value of δ 13 C ranged from -21.1‰ to -16.7‰ of the food web in Dalian marine area. The major biological species could be categorized into three groups, namely primary consumer, secondary consumer and top predator. The analysis of δ 15 N revealed that the trophic level ranged from 2.63 to 4.59 for the major biological species. The trophic level of B. acutorostrata, N. asiaorientalis sunameri, P. largha, echinoderm, cephalopods, gastropod, bivalve, crustacean and fish were 3.16, 4.11, 4.25, 3.24-3.84, 3.81-3.93, 3.65-4.13, 2.63-3.15, 3.58-4.12 and 3.20-4.59, respectively. The characteristics of the trophic structure demonstrated that the primary consumer was bivalve, the secondary consumers were B. acutorostrata, cephalopods, Echinoderms, gastropod and crustacean, and top predators were N. asiaorientalis sunameri, P. largha and fish. The value of δ 15 N increased with the increase in the body length, indicating the feeding of N. asiaorientalis sunameri tended to be at a higher trophic level with the growth and feeding ability enhanced. This study established the continuous trophic spectrum of food web in Dalian marine area and would provide the information for the marine mammal and fisheries resources protection.

Objective: To devAop a new approach for functional penile reconstruction., Methods: Total penile reconstruction using innervated gracilis muscles and anterolateral thigh (ALT) flap with fascia lata was performed on four human cadavers. Canine models were constructed using gracilis muscles and lower abdominal flap with anterior rectus sheaih, instead of the ALT flap. Seven months later, the erectile function of the neophalli elicited by electrostimulation was evaluated. The length, diameter and stiffness were measured respectively and the results were analyzed statistically using paired-samples t test., Results: The penile reconstruction was success with good appearance in the cadaveric study. The hardness of the reconstructed penis in canine models was graded as 1.2 ± 0.4 at rest. With the nerve pedicles stimulated, it increased significantly and was graded as 3.4 ± 0.5 (P ＜ 0.05),while the length shortened and the diameter did not change significantly. A successful erection-mimic course was observed., Conclusions: It indicates that penile reconstruction with skin flaps combined with muscle is feasible, serving as a theoretical and technical support for further clinical application.