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The aim of the present study is to evaluate the potential ecological risk and trend of soil heavy-metal pollution around a coal gangue dump in Jilin Province (Northeast China). The concentrations of Cd, Pb, Cu, Cr and Zn were monitored by inductively coupled plasma mass spectrometry (ICP-MS). The potential ecological risk index method developed by Hakanson (1980) was employed to assess the potential risk of heavy-metal pollution. The potential ecological risk in the order of ER(Cd) > ER(Pb) > ER(Cu) > ER(Cr) > ER(Zn) have been obtained, which showed that Cd was the most important factor leading to risk. Based on the Cd pollution history, the cumulative acceleration and cumulative rate of Cd were estimated, then the fixed number of years exceeding the standard prediction model was established, which was used to predict the pollution trend of Cd under the accelerated accumulation mode and the uniform mode. Pearson correlation analysis and correspondence analysis are employed to identify the sources of heavy metals and the relationship between sampling points and variables. These findings provided some useful insights for making appropriate management strategies to prevent or decrease heavy-metal pollution around a coal gangue dump in the Yangcaogou coal mine and other similar areas elsewhere.

Extracting accurate atmospheric parameters and elemental abundances from stellar spectra is crucial for studying the Galactic evolution. In this paper, a deep neural network architecture named StarNet is used to estimate stellar parameters (T eff, log g, [M/H]), α-elements as well as C and N abundances from LAMOST spectra, using stars in common with APOGEE survey as training data set. With the spectral signal-to-noise ratio (S/N) in g band (S/N g ) larger than 10, the test indicates our method yields uncertainties of 45 K for T eff, 0.1 dex for log g, 0.05 dex for [M/H], 0.03 dex for [α/M], 0.06 dex for [C/M] and 0.07 dex for [N/M]. Because of few stars with [M/H] < −1.0 dex in the training set, the uncertainties are dominated by stars with [M/H] > −1.0 dex. Based on test results, we think StarNet is valid for measuring parameters from low-resolution spectra of the LAMOST survey. The trained network is then used to predict parameters for 938,720 giants from LAMOST DR5. Within the range of stellar parameters 4000 K < T eff < 5300 K, 0 dex < log g < 3.8 dex and −2.5 dex < [M/H] < 0.5 dex, the comparisons with high-precision measurements (e.g., PASTEL, asteroseismic log g) yield uncertainties of 100 K for T eff, 0.10 dex for log g, 0.12 dex for [M/H]. Our estimations are consistent with values from the high-precision measurements. In this research, a deep neural network is successfully applied on the numerous spectra from LAMOST. The deep neural network shows an excellent performance, which demonstrates that deep learning can effectively reduce the inconsistencies between parameters measured by the individual survey pipelines.

Long noncoding RNA (lncRNA) has been increasingly implicated in the regulation of muscle development. Large White pigs have a higher muscle growth rate than do Mashen pigs. In the present study, the lncRNA expression profiles in skeletal muscle of these 2 pig breeds were compared at 1, 90, and 180 d of age using RNA sequencing. We obtained 2,718 million clean reads and identified a total of 5,153 novel lncRNA. We found 1,407 differentially expressed lncRNA that showed consistent expression patterns between the 2 breeds at all the 3 sampling points. Ten lncRNA were randomly selected, and their expression was validated using Real-time Quantitative PCR. In summary, this study identifies a number of lncRNA that correlate with muscle growth. The regulation and function of these lncRNA in muscle growth and development need to be further explored.

The potassium feldspar ore in a certain area of Chengde contains K2O 9.82%, Na2O 2.41%, which belongs to the high quality feldspar ore. It cannot be exploited and utilized because of the high iron content. An experimental research was carried out to remove iron from a feldspar ores in this area by the technique of high gradient magnetic separation respectively. The properties of potassium feldspar ore were analyzed, and the technology for iron removal from potash feldspar ore was expounded. The optimum parameters were determined. Finally, the content of Fe2O3 in the potash feldspar was reduced from the original 0.88% to 0.082%, significantly reduced the content of Fe2O3. The effect of iron removal was ideal, and the products can meet the requirements of high-grade daily porcelain on feldspar raw materials.

To improve the isolation ability of the existing equipment for low-frequency line spectrum, this paper presents an electromagnetic double-layer vibration isolation system (ED-VIS) for the first time. The negative and positive stiffness values of the ED-VIS are provided by the electromagnet and the linear spring, respectively. To better analyze the vibration isolation system designed in this paper, the dynamic model of the ED-VIS is established, and the effects of damping ratio, excitation force amplitude, and mass ratio on the force transmissibility feature of the isolator are analyzed. Then, the ED-VIS test bench is built, and the low-frequency vibration isolation capability of the ED-VIS is measured by a frequency sweep test. According to the sweep test results, a method to improve the low-frequency vibration isolation capability of the isolator is proposed. Finally, the reliability of the system in isolating low-frequency vibration is verified. The results show that compared with the equivalent linear vibration isolation system, ED-VIS is more sensitive to low-frequency vibration and has a lower initial vibration isolation frequency. Therefore, this paper designs the ED-VIS has better low-frequency vibration isolation performance.

Previous studies demonstrated that myopia could result in alterations of brain activity in specific areas. However, whether the visual function could improve by Lasik surgery, with the brain activity alterations also change, is still unknown. Here, we intended to use the amplitude of low-frequency fluctuation (ALFF) technique to investigate the intrinsic brain activity changes in pre-Lasik (PRL) and post-Lasik (POL) patients. A total of 15 patients with myopia (nine male and six female) were recruited in our study, who were matched according to age, weight, and height. These patients comprised both the PRL and POL groups, which is self-controlled. The patients all underwent resting-state functional magnetic resonance imaging (MRI), and the spontaneous brain activity changes were recorded by the ALFF technique. The data were recorded and arranged in the receiver operating characteristic (ROC) curve, which presented how intrinsic activities altered in different brain regions. Moreover, by Graphpad prism 8, we can analyze the linear correlation between HADS (Hospital Anxiety and Depression Scale) and ALFF values as well. Differences in ALFF values existed in brain regions between the same patient before and after the Lasik operation. The regions with increased ALFF values after Lasik surgery were the left parahippocampal gyrus, cerebellar vermis, and left posterior cingulate cortex. The regions with decreased ALFF values after Lasik surgery were the left supramarginal gyrus and right trigonometric inferior frontal gyrus. We demonstrated significant fluctuations of ALFF values in specific brain areas between the same patients before and after the Lasik surgery. The altered ALFF values reflected the hyperactivity or hypoactivity of the specific brain areas, which may help predict the recovery level of patients' vision after Lasik surgery. Furthermore, based on the experimental results that presented significant activity alterations in specific brian regions, patients could be speculated equipped with a better visual function.

This paper presents a new type of brace system to strengthen transversal connection of T beam bridges. A nylon T beam bridge was made to study the strengthening effect. Braces were installed in the mid span and the load was symmetrical. The results show that the reduction of the maximum deflection of the bridge with the brace system was 14.9% in experiments and 19.1% in finite element analysis, which show that the transversal connection of T beam bridge can be improved efficiently by the proposed brace system.

Preparation of iron oxide red (α-Fe2O3) from the converter dust by the superconductivity high gradient magnetic separation (S-HGMS) and roasting process was investigated in the paper. The basic properties of the dust were studied by the X Ray Fluorescence, the chemical analysis and the X Ray Diffraction methods. The results showed that the raw dust mainly contained elements of Fe‵O‵Si‵Ca, the iron content of the raw dust was 61.80%, and there were ferrous phases of Fe3O4, α-Fe2O3, Fe2(SiO4) and CaFe(Si2O6) in the raw dust. Under the optimum conditions of magnetic field intensity of 1.8T, the dispersion agent of 30mg/L and velocity of 500mL/min, the powders absorbed by the magnetic medium mainly contained Fe3O4 and α-Fe2O3, and the iron content of powders absorbed was up to 65.90%. The Fe2+ content of the powders absorbed under the optimum magnetic conditions dropped to 0.25% from 19.10% after roasting of fifty minutes, and the iron content of powders absorbed under the optimum magnetic conditions fell to 64% due to oxidation, and the Fe3O4 was removed. Finally the α-Fe2O3 content was up to 91.07% in the iron oxide red.

Purpose – The samples of nickel foam with porosity of about 88 percent were uniaxially tensioned at room temperature, and the phenomena of tensile fracture were compared with that from the fully dense plate of metal nickel. The purpose of this paper is to investigate the differences between their behaviors of tensile fracture. Design/methodology/approach – The tensile test was carried out by using the tester of CMT-series microcomputer-controlled electronic universal testing machine. The difference of tensile fracture behavior between the nickel foam and the dense metal nickel was discussed by analyzing the load-displacement curve and the microscopical fracture. Findings – The results indicated that, nickel foam also displayed the feature of macroscopic plastic-deformation during tension, but it showed a macroscopic brittleness much more than that of the fully dense body. The axial apparent strain at the maximum load for the foamed sample was markedly less than that for the dense one. In addition, an obviously gradual course exhibited for the foamed body during tensile failure and a rapidly instant course for the dense body correspondingly. Originality/value – There have been some studies on the tensile behavior for metal foams, but much less than on the compression, and the relevant works are mostly for aluminum foam. The present work provides the investigations on the difference of tensile fracture behavior between the nickel foam and the dense metal nickel, as well as that of the corresponding samples in various cases with different tensile velocities. It is found that the porosity can make a remarkable decrease of the apparent strain at the maximum load and a significant increase of the macroscopical brittleness for the metallic nickel under tension.

We report a relatively rare case of renal replacement lipomatosis presenting as a renal mass. Computed tomography revealed a predominantly low-density and roundish mass, with an irregular renal parenchyma, high-density calcification, and abundant low-density fat. The differential diagnosis before surgery was squamous cell carcinoma, teratoma, or angiomyolipoma of the kidney. The case was initially misdiagnosed, because we had no experience with this disease. After mass exploration, histological examination confirmed the diagnosis of renal replacement lipomatosis. The patient was free from signs of recurrence 10 months after the operation.