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GH907 superalloy has been widely used in aircraft，ship and other industries.Because GH907 superalloy will be corroded when used in marine environment， it is necessary to study its corrosion behavior.In this work， the corrosion behavior of GH907 superalloy material in simulated marine environment was studied by neutral salt spray test.The 2D and 3D morphology of GH907 superalloy after corrosion were observed by means of scanning electron microscope (SEM)，X-ray energy dispersive spectroscopy (EDS) and 3D confocal laser scanning，and the composition of GH907 superalloy was analyzed.Moreover，the electrochemical corrosion behavior of GH907 superalloy was analyzed through electrochemical tests of potentiodynamic scanning and electrochemical impedance spectroscopy.Results showed that GH907 material would undergo passivation behavior during neutral salt spray corrosion.After corrosion， the corrosion current density of GH907 increased， the corrosion resistance decreased， and the corrosion products and passivation film possessed limited ability to protect the material.Furthermore， the main corrosion type was pitting corrosion.EDS results revealed that the corrosion products in the pitting pits were mainly Fe oxides， with very low Ni and Co element contents.Besides， the charge transfer and diffusion behavior existed in the corrosion process， and the corrosion system was an activation control system.

Background Diabetes mellitus has been a major concern as a common risk factor for cardiovascular disease. Glycated hemoglobin (HbA1c) variability is an indicator of long-term blood glucose fluctuation. Therefore, it is of great clinical significance to explore the correlation between HbA1c variability and new-onset atrial fibrillation (AF) in diabetic patients combined with heart failure with preserved ejection fraction (HFpEF) . Objective To investigate the correlation between HbA1c variability and new onset AF in type 2 diabetes mellitus (T2DM) patients combined with HFpEF. Methods The clinical data of 317 T2DM patients combined with HFpEF diagnosed in the Department of Cardiology, the Second Affiliated Hospital of Zhengzhou University from January 2018 to January 2019 were retrospectively analyzed. The follow-up was performed until February 2022, with a mean follow-up time of 3.4 years. The included patients were divided into the AF group (34 cases) and non-AF group (283 cases) based on the presence of new-onset AF during the follow-up period. The HbA1c variability was expressed as standard deviation of HbA1c measurement (HbA1c-SD) and HbA1c coefficient of variation (HbA1c-CV). Multivariate Cox regression analysis was used to explore the correlation between HbA1c variability and new-onset AF in T2DM patients combined with HFpEF. The survival curves were plotted by the Kaplan-Meier (K-M) method. The receiver operating characteristic (ROC) curve of HbA1c variability predicting new-onset AF in T2DM patients combined with HFpEF was plotted. Results The HbA1c-SD and HbA1c-CV of patients in the AF group were higher than those in the non-AF group (P0.34%, HbA1c-CV>4.74%) groups according to the median of HbA1c variability. Log-rank test results showed higher incidence of new-onset AF in patients with high HbA1c variability (PHbA1c-SD0.34%, HbA1c-CV>4.74%) is independently associated with an increased risk of new-onset AF in T2DM patients combined with HFpEF, with significant clinical value in predicting AF.

In order to protect the geographical origin information of Chinese chestnut as a geographical indication product, 164 Chinese chestnut samples were collected from 10 provinces, including Qianxi in Hebei, Jixian in Tianjin and Huairou in Beijing for analysis of stable isotopes (C, H, O, and N) and mineral elements using elemental analysis-stable isotope mass spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). Analysis of variance (ANOVA), principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to classify the production regions of Chinese chestnut and establish a geographical origin traceability model. The results showed that the cross-validation rate of the OPLS-DA model for the 10 geographical origins was 100%, and the area of the receiver operating characteristic (ROC) curve was close to 1. The elements Mg, δ2H, δ18O, Al, Na, δ15N, Cu, Ba, Zn and Th were the main factors (variable importance in the projection, VIP > 1) to distinguish Hebei chestnuts and those from the other nine production regions. The established model can provide an effective theoretical basis for geographical origin discrimination of Chinese chestnut.

In order to explore the effect of hammering time on the quality of beef gel, beef gel prepared by beating process was used as control group, the color difference, myofibrillar protein oxidation degree, cooking loss rate, fat exudation rate and texture characteristics of beef gel with different beating time were determined, and the mechanism of the impact of beat time on beef gel quality was studied through observing the changes of meat size, protein two level structure and microstructure of beef gel. The results showed that with the extension of beating time, the L* value and W value first decreased and then increased, and the a* value and b* value increased first and then decreased. The oxidation degree of myofibrillar protein increased, total thiol decreased, the carbonyl value and bromphenol blue binding capacity increased, cooking loss rate decreased and then increased with fat exudation, and the hardness and chewiness of gel texture increased gradually. Resilience, cohesion and resilience increased first and then decreased. 30 min was the cut-off point, and the gel quality of 30 min was on the rise, which was more than 30 min. The increasing of gel quality was due to the decreasing of meat particle size and the increasing of protein two level structure beta fold. The degradation of gel quality after 30 min was due to the deepening of protein oxidation and the change of gel microstructure. The results showed that the hammering process could improve the quality of minced meat, but excessive hammering could cause the quality deterioration of minced meat.

Water electrolysis can transform unstable renewable energy into the hydrogen energy and realize large-scale and seasonal energy storage, which is one of the key means to achieve the goal of "carbon neutrality" in China. The technology of high temperature solid oxide electrolysis cell (SOEC) was discussed and studied, and the working principle of the high temperature solid oxide electrolysis was introduced. According to its actual operation characteristics, the electrochemical model and thermodynamic model of electrolysis process were established, and the models were verified by comparing with the experimental data. Furthermore, the effects of current density and operating temperature on the high temperature solid oxide electrolysis were analyzed, and the thermodynamic analysis was conducted. The results show that the thermal integration and management of SOEC at high temperature will be conducive to reduce the power consumption. If the high-temperature electrolysis process is combined with other industrial processes and utilized the low-grade industrial waste heat, the overall efficiency of high-temperature solid oxide electrolysis is expected to be further improved.

Conducting the soil environmental condition survey and accessing the distribution and potential sources of heavy metals and arsenic in soils in Xiongan New Area are of great significance for the land resources and environment management of the district. Based on the data of soil survey samples in the Xiongan New Area, spatial distributions of the elements (As, Hg, Cd, Cu, Pb, Zn, Ni and Cr) are analyzed and computed by using geostatistics and ArcGIS techniques. A combination of spatial analysis, multivariate statistical analysis, and positive matrix factorization model is used to assess the sources of these elements. The result show that the soil quality is good and the pollution risk is low. Approximately 4.35% of the soil samples for Cd and Cu have total concentrations higher than the risk screening values for soil contamination of agricultural land, and lower than the risk control values for soil contamination of agricultural land. However, moderate and significant enrichment in Cd, Cu, Pb, Zn and Hg in the surface soils was observed compared with their background values of Hebei province. The contents of As, Cd, Cu, Pb, Zn, Ni and Cr exhibite a gradually increasing trend from north to south. These elements principally concentrate in the southwest of the study area. The distribution of Hg is relatively dispersed, and the high-values are mainly located in the urban and industrial areas. The vertical distributions of heavy metals and arsenic in soils of different landuse types are dominantly controlled by physicochemical factors such as pH, organic carbon, and Fe/Al oxides. Anthropogenic sources contribute 67.12% of the heavy metal concentrations in soils, indicating the great influence on soil heavy metal accumulation. Hg is dominated by atmospheric deposition related to anthropogenic emissions such as coal combustion and smelting activities. As is principally affected by industrial activities. Cd, Cu, Pb and Zn are influenced by anthropogenic activities such as industrial production, sewage irrigation and vehicle emission.

Data race is a major factor which causes multi-core programs to produce concurrent bugs.To address the high hardware cost in happens-before detection proposals,a light-weight hardware data race detection approach based on sliding window technology was proposed.It used sliding windows to save recent memory instructions in thread execution and dynamically detected data races with small race distance which more easily lead to concurrent bugs.Considering the race distance,parallel thread segments were subdivided into concurrent race regions with lock and concurrent race regions without lock.A pair of alternate rewritable sliding windows was used to store the memory instructions in concurrent race region without lock,and a sliding window with variable size was used to store the memory instructions in concurrent race region with lock.When there was a conflict between a remote sharing access and memory accesses in sliding windows,a data race was detected.In the hardware implementation,the addresses of the data in sliding windows were automatically encoded into three hardware signatures with small size.Data races can be detected quickly without modifying the L1 cache and cache coherence protocol messages.This approach supplies efficient guidance to help users to diagnose concurrency bugs occurred in the development and production run of multi-core programs,achieving smaller hardware and bandwidth overhead.

A potential attack based on degree information by re-identifying target vertexes from a sequence of published graphs was analyzed.To deal with this kind of attack,a k-anonymous graph stream constructing method based on information loss estimation was provided.Information loss caused by re-constructing graph was controlled by using the method of attributes generalization of nodes and the structure generalization of sub-graph.The disturbance in sub-graph was forbidden to prevent the attack.The method of measuring the information loss of nodes and structures during the anonymous process due to re-construction of graph was defined.A k-anonymity cluster algorithm based on greedy clustering algorithm was build,which realized anonymous partition according to the information loss.Finally,a method of constructing anonymous social network for the evolving social network with the least information loss was provided.The experiments on medical diagnostic data set show that the algorithm of constructing anonymous graph based on the information loss estimation can be used to control the loss of information.

Objective To investigate the efficacy and safety of CyberKnife for giant cavernous hemangioma in cavernous sinus. Methods The data of 7 cases of giant cavernous hemangioma in cavernous sinus region confirmed by imaging examination and treated with CyberKnife were collected. The tumor volume was 11.86-70.12 cm3 (median 23.30 cm3). CT and MRI were acquired and fused by MIM 6.5.4 software. The acquired data sets were imported into a CyberKnife Robotic Radiosurgery System (Multiplan 4.0.2) and used to delineate the target organs at risk. The irradiation doses received by the lesions were 21 Gy/3 times in 5 cases, 25 Gy/5 times in one case and 30 Gy/3 times in one case. The exposure field was 109-155, and target volume reached over 95%. Patients maintained at supine positionduring treatment and utilized a 6D-skull trace mode specific to CyberKnife. Changes of clinical symptoms and imaging immediately after treatment and during follow-up period were observed to evaluate the efficacy and safety of this therapeutic method. Results Patients were followed-up for 6-18 months, and the meanfollow-up period was 9.37 months. Volumes of lesions were calculated after operation. All of these patients showed decrease in tumor volume (35.48% to 84.03% ) and improvement in symptoms (including visual impairment, visual field defect and headaches) after therapy. Postoperative MRI revealed the tumor volume was 6.75-28.35 cm3 (median 10.50 cm3), which were significantly lower than that of before treatment [11.86-70.12 cm3 (median 23.30 cm3); Z = -2.366, P = 0.018]. Only one case presented radioactive cerebral edema, and the symptom was disappeared after 5-day treatment with mannitol and dexamethasone. Conclusions CyberKnife is an effective treatment method for giant cavernous hemangioma in cavernous sinus region. It is suggested to be the first selection for patients with giant cavernous hemangioma in cavernous sinus, who are not suitable for traditional surgeries and general radiotherapy. DOI: 10.3969/j.issn.1672-6731.2015.10.008

Objective To explore the clinical value of optic radiation reconstruction in protecting against visual field deficits (VFDs) in anterior temporal lobectomy (ATL). Methods We retrospectively analyzed 24 patients with medically refractory temporal lobe epilepsy undergoing ATL between January 2013 and June 2014. The surgical operations were aided by combining optic radiation reconstruction by diffusion tensor tractography (DTT), microscopy-based neuronavigation and intraoperative MRI (iMRI) techniques. ATL was performed according to the distance between Meyer's loop and temporal pole. The visual fields were examined and seizure outcomes were evaluated by Engel class test in 3-month follow-up. Results The optic radiation was reconstructed in all patients. No bleeding was found in operative site or distant site by iMRI scan. The size of removed temporal lobe was 3.29 cm (1.90-5.10 cm). Visual field testing 3 months after operation showed no VFDs in 16 cases (66.67%) and mild VFDs (< 1/4 quadrant) in 8 cases (33.33% ). One case suffered mild VFD before operation, but did not aggravate after operation. Engel class test showed Engel classⅠin 19 patients (79.17%), class Ⅱ in 4 patients (16.67%) and class Ⅲ in one patient (4.17%). Conclusions For patients with medically refractory temporal lobe epilepsy, the techniques of combining optic radiation reconstruction, microscopy-based euronavigation and iMRI aided in precise mapping could reduce the risk of visual field deficits in anterior temporal lobectomy. DOI: 10.3969/j.issn.1672-6731.2015.09.005

Objective To evaluate the accuracy and safety of deep brain electrode implantation assisted by robotized stereotactic assistant (ROSA) system. Methods A total of 6 epileptic patients who had difficulty in positioning of epileptogenic focus underwent deep brain electrode implantation assisted by ROSA system. Record the maximum and minimum distance of electrode deviation according to postoperative CT and MRI and calculate the average distance, so as to evaluate the accuracy of operation. Record intraoperative electrode related bleeding events, postoperative electrode related bleeding or ischemic events and complications during the follow-up period, so as to evaluate the safety of operation. Results A total of 37 electrodes were successfully implanted in all 6 cases, with a success rate of 100%. Implanted electrodes were mainly located in medial temporal lobe, hippocampus and insular lobe (5 cases) and parieto-lobe (one case). The maximum deviation distance was 8.79 mm, and minimum was 1.14 mm, with an average of (3.65 ± 1.82) mm. Neither intraoperative electrode related bleeding event nor postoperative electrode related bleeding or ischemic event was found. No patient suffered from severe complications, such as intracranial infection, electrode disjunction, undesirable healing of scalp and wound infection, during the follow-up period from 3 to 5 months (mean 3.67 months). Conclusions Deep brain electrode implantation assisted by ROSA system is safe and accurate. DOI: 10.3969/j.issn.1672-6731.2015.09.006

Taking the long-term reforestation experimental base established in a severely degraded sub-tropical hilly red soil region in Taihe County of Jiangxi Province in 1991 as the object, this paper studied the changes of soil nutrients and microbial communities after 19 years reforestation of Pinus elliottii forest, Liquidambar formosana forest, and P. elliotti-L. formosana forest, with the naturally restored grassland as the control. The soil organic carbon content in the L. formosana and P. elliottii-L. formosana forests (15. 16±3. 53 and 16. 42±0. 49 g · kg-1, respectively) was significantly higher than that in the control (9. 30±1. 13 g · kg-1), the soil total phosphorus content was in the order of the control (0. 30±0. 02 g · kg-1 ) > P. elliottii-L. formosana forest (0.22±0.04 g · kg-1) > L. formosana forest (0. 14±0. 01 g.kg-1), while the soil available phosphorus content was 1. 66±0. 02 mg · kg-1 in L. formosana forest, 2. 47±0. 27 mg · kg-1 in P. elliottii-L. formosa- na forest, and 1. 15±0. 71 m g · kg-1 in P. elliottii forest, being significantly higher than that in the control (0. 01±0. 00 mg · kg-1). The total amounts of soil microbes, the amount and percentage of soil bacteria, and the amount of inorganic and organic phosphate-solubilizing microbes in L. formosana forest and P. elliottii-L. formosana forest were all significantly higher than those in P. elliottii forest and the control, while the amount and percentage of soil fungi and the percentage of soil actinomycetes in L. formosana forest and P. elliottii-L. formosana forest were significantly lower than those in the control. The soil organic carbon content was significantly positively correlated with the percentage of soil bactera, but negatively correlated with the percentage of soil fungi and actinomycetes, while the soil available phosphorus content was significantly positively correlated with the amount of organic phosphate-solubilizing microes, but not with the amount of inorganic phosphate- solubilizing microbes. It was suggested that L. formosana forest and P. elliottii-L. formosana forest could be the recommended reforestation models in sub-tropical degraded red soil region. [ABSTRACT FROM AUTHOR]

Taking the long-term reforestation experimental base established in a severely degraded sub-tropical hilly red soil region in Taihe County of Jiangxi Province in 1991 as the object, this paper studied the changes of soil nutrients and microbial communities after 19 years reforestation of Pinus elliottii forest, Liquidambarformosana forest, and P. elliotti-L. formosana forest, with the naturally restored grassland as the control. The soil organic carbon content in the L. formosana and P. elliottii-L. formosana forests (15.16+/-3.53 and 16.42+/-0.49 g kg-1, respectively) was significantly higher than that in the control (9.30+/-1.13 g kg-1), the soil total phosphorus content was in the order of the control (0.30+/-0.02 g kg-1) > P. elliottii-L. formosana forest (0.22+/-0.04 g kg-1 ) > L. formosana forest (0.14+/-0.01 g kg-1 ), while the soil available phosphorus content was 1.66+/-0.02 mg kg-1 in L. formosana forest, 2.47+/-0. 27 mg kg- in P. elliottii-L. formosana forest, and 1. 15+/-0.71 mg kg-1 in P. elliottii forest, being significantly higher than that in the control (0.01+/-0.00 mg kg-1). The total amounts of soil microbes, the amount and percentage of soil bacteria, and the amount of inorganic and organic phosphate-solubilizing microbes in L. formosana forest and P. elliottii-L. formosana forest were all significantly higher than those in P. elliottii forest and the control, while the amount and percentage of soil fungi and the percentage of soil actinomycetes in L. formosana forest and P. elliottii-L. formosana forest were significantly lower than those in the control. The soil organic carbon content was significantly positively correlated with the percentage of soil bactera, but negatively correlated with the percentage of soil fungi and actinomycetes, while the soil available phosphorus content was significantly positively correlated with the amount of organic phosphate-solubilizing microes, but not with the amount of inorganic phosphate-solubilizing microbes. It was suggested that L. formosana forest and P. elliottii-L. formosana forest could be the recommended reforestation models in sub-tropical degraded red soil region.

Prevalence of antibiotic-resistant bacteria in wastewater effluents is concerned as an emerging contaminant. To estimate antibiotic resistance in secondary effluents of municipal wastewater treatment plants, antibiotic tolerance of heterotrophic bacteria, proportion of antibiotic-resistant bacteria and hemi-inhibitory concentrations of six antibiotics (penicillin, ampicillin, cefalexin, chloramphenicol, tetracycline and rifampicin) were determined at two wastewater treatment plants (WWTPs) in Beijing. The results showed that proportions of ampicillin-resistant bacteria in WWTP-G and chloramphenicol-resistant bacteria in WWTP-Q were highest to 59% and 44%, respectively. The concentrations of ampicillin-resistant bacteria in the effluents of WWTP-G and WWTP-Q were as high as 4.0 x 10(3) CFU x mL(-1) and 3.5 x 10(4) CFU x mL(-1), respectively; the concentrations of chloramphenicol-resistant bacteria were 4.9 x 10(2) CFU x mL(-1) and 4.6 x 10(4) CFU x mL(-1), respectively. The data also indicated that the hemi-inhibitory concentrations of heterotrophic bacteria to 6 antibiotics were much higher than common concentrations of antibiotics in sewages, which suggested that antibiotic-resistant bacteria could exist over a long period in the effluents with low concentrations of antibiotics. Antibiotic-resistant bacteria could be a potential microbial risk during sewage effluent reuse or emission into environmental waters.