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At present, the detection of mining subsidence basins by interferometric synthetic aperture radar (InSAR) mainly relies on underground mining data or human visual interpretation. To solve this problem, this paper proposes a deformation basin detection network (DBD-Net) for large-scale InSAR interferograms. At the same time, in order to train the network, a sample database of mining subsidence basins is established by using real differential interferogram data and simulated interferogram data. In Shendong Mining Area and Yanzhou Mining Area, three differential interference images with different time baselines were selected to verify the network performance. The results show that the detection accuracy of deformation basin detection network (DBD-Net) in large-scale InSAR interferograms for mining subsidence basins is 81.87%. Most of the missed and false detection areas are areas with serious noise pollution and unclear characteristics.

BackgroundPublic places are frequently polluted by cigarette smoking, and there is a lack of accurate, real-time, and intelligent monitoring technology to identify smoking behavior. It is necessary to develop a tool to identify cigarette smoking behavior in public places for more efficient control of cigarette smoking and better indoor air quality. ObjectiveTo construct a model for recognizing cigarette smoking behavior based on real-time indoor concentrations of PM2.5 in public places. MethodsReal-time indoor PM2.5 concentrations were measured for at least 7 continuous days in 10 arbitrarily selected places (6 public service providers and and 4 office or other places) from Oct. to Nov. 2022 in Pudong New Area, Shanghai. Indoor nicotine concentrations were monitored with passive samplers simultaneously. Outdoor PM2.5 concentration data were obtained from three municipal environmental monitoring stations which were nearest to each monitoring point during the same period. Mann-Whitney U test was used to compare indoor and outdoor means of PM2.5 concentrations, and Spearman rank correlation was used to analyze indoor PM2.5 and nicotine concentrations. An interactive plot and a random forest model was applied to examine the association between video observation validated indoor smoking behavior and real-time indoor PM2.5 concentrations in an Internet cafe. ResultsThe average indoor PM2.5 concentration in the places providing public services [(97.5±149.3) µg·m−3] was significantly higher than that in office and other places [(19.8±12.2) µg·m−3] (P=0.011). The indoor/outdoor ratio (I/O ratio) of PM2.5 concentration in the public service providers ranged from 1.1 to 19.0. Furthermore, the indoor PM2.5 concentrations in the 10 public places were significantly correlated with the nicotine concentrations (rs=0.969, P

The experiment explored the effect of curing conditions on the component content of dried and air-dried corn. A two-factor experimental design was adopted, with drying methods and curing conditions as independent variables, drying methods at two levels, and curing conditions at ten levels. The results showed that the drying method had a significant effect on corn resistant starch content under maturation conditions (P<0.05), and the drying basis was significantly higher than the air-dried basis (P<0.05), maturation had a significant effect on corn starch content (P<0.05). The interaction of curing and drying methods had a significant effect on content of starch components (P<0.05). Compared with corn at 0 level (0 °C, 0 min), on other levels, amylopectin content, total starch content were decreased, the amylose content and the resistant starch content was increased. When the ripening time was 30~60 min and the ripening temperature was 120 °C, the corn was ripened, the air-dried base corn amylose content increased from 13.96% to 19.21%, and the total starch content increased from 68.49% to 71.17%. The content of resistant starch was relatively stable. The experiment indicates that under the condition of 30~60 min and a curing temperature of 120 °C, the content of air-dried corn amylose and total starch increase with the increase of the curing time, and the curing time has little effect on amylopectin and resistant starch. [ABSTRACT FROM AUTHOR]

To improve the application of hematology and urine testing of laboratory animals, and the consistency and effectiveness of the on-site review in China, there is a need for further standardization of the expression of testing ability in this field. In addition, it promotes better understanding and acceptance of the China National Accreditation Service for Conformity Assessment (CNAS) recognized results by relevant parties. In this paper, the expression of the accredited competence scope in the domestic and international institutes of laboratory animal hematology, blood biochemistry, and urine analysis fields were analyzed and compared. This study provides the CNAS with recommendations to standardize the expression of accreditation ability. In addition, it provides a detailed theoretical reference for further improving the process of standardizing testing of laboratory animals in China.

In this study, five strains of Lactobacillus rhamnosus (L. rhamnosus) and two strains of Lactobacillus paracasei (L. paracasei) isolated from infants were used as experimental bacteria and Lactobacillus rhamnosus GG as control strain. The gastrointestinal tolerance of these strains were evaluated through acid resistance test, bile salt resistance test, hydrophobicity test, automatic aggregation ability test and cell adhesion test. L. rhamnosus SW-02, the best effective strain in tolerance evaluation, was co-cultured with intestinal organoids. The morphology and growth status of organoids were observed by inverted phase contrast microscope, and the budding rate was calculated. The proliferation status of organoids was evaluated by EdU staining. The mRNA levels of the proliferation marker Ki67, intestinal stem cell marker Lgr5 and tight junction protein Zo-1 were measured by real-time PCR. The level of MUC2 was detected by enzyme-linked immunosorbent assay. The results showed that compared with other strains, L. rhamnosus SW-02 had strong acid resistance. SW-02, SW-03 and SW-X had strong bile salt resistance. LGG, SW-01, SW-02, SW-04 and TX-02 had high hydrophobicity to xylene. For automatic aggregation capability, SW-01 was the strongest, followed by SW-02. The adhesion test of HT-29 cells showed that SW-01, SW-02 and SW-03 had high adhesion ability. When SW-02 was co-cultured with intestinal organoids, SW-02 significantly (P

BACKGROUND Heavy metal pollution in soil has been a serious threat to human health and ecological environmental safety. Stabilization remediation has become an important means of remediation of heavy metal contaminated soil due to the high efficiency and low cost. Attapulgite modified by alkali with an improved performance, provides an important basis for its stabilization and remediation of heavy metal contaminated soil. OBJECTIVES To analyze the changes in physical and chemical properties of attapulgite before and after modification, and to study the effects of attapulgite modified by NaOH on the chemical speciation changes and environmental risks of Cd in contaminated soil, and to explore the stabilization effects of attapulgite modified by NaOH on Cd in the soil. METHODS Different proportions of NaOH were used to modify attapulgite. The surface characteristics, crystal structure and functional groups of the materials were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Stabilization experiments were carried out on artificially prepared heavy metal Cd contaminated soil to study the effects of NaOH-modified attapulgite on the changes of chemical speciation of Cd and environmental risks in contaminated soil. RESULTS By adding the modified material with the mass ratio of NaOH to attapulgite of 1:2, the pH value of the soil was significantly increased by 0.85 units. The exchangeable Cd content decreased by 46.28% and the residual Cd content increased by 1.98 times. The risk assessment code (RAC) and potential risk index (PRI) of Cd in soil decreased the most from 36.70% and 207.90 to 20.08% and 86.40, respectively, which effectively reduced the transfer capacity and environmental risk of Cd in soil. According to SEM, XRD and FTIR analyses, after modification, the surface roughness of attapulgite increased, chemical bonds such as Si-O-Si bonds were opened, so active sites for adsorption of heavy metals increased. Attapulgite modified by alkali immobilized Cd mainly through adsorption, and the reaction of silanol and hydroxide with Cd2+ generated precipitate, so as to achieve the effect of stabilizing and repairing Cd contaminated soil. CONCLUSIONS Alkali-modified attapulgite can effectively stabilize Cd in soil, which has a significant application prospect in remediation of heavy metal contaminated soil.

Recombinase polymerase amplification (RPA) is a novel isothermal nucleic acid amplification technology. Compared to PCR, it features ease of use, high efficiency, high sensitivity, high specificity, and does not need specific instruments, which allows it as an alternative to PCR and the most promising tool for rapid molecular diagnosis. RPA combined with lateral flow dipstick (LFD) (RPA-LFD) enables visual detection of amplified products and has promising applications for rapid nucleic acid detection of pathogens on site. The novel technique provides a new method for quality supervision and inspection of laboratory animals. In this paper, we reviewed the principle, research status, and technical difficulties of RPA-LFD, as well as the progress in rapid extraction of nucleic acid on site.

Objective To investigate the pregnant women's fear of childbirth and its influencing factors, and analyze the relationship between fear of childbirth and social support. Methods A convenient sample of 101 pregnant women were recruited and investigated by using a self-made general information questionnaire, the Chinese version of Childbirth Attitudes Questionnaire (CAQ) and Perceived Social Support Scale (PSSS). Results The dimension score of fetal health was higher than other three dimension of CAQ. There was a significant difference in CAQ score between pregnant women with different employment status(P＜0. 01). There was no correlation between social support level and fear of childbirth among pregnant women. Conclusion Findings of the study showed a high awareness of fetal health among pregnant women, and employment status is a potential influencing factor of attitude toward childbirth. Targeted interventions are required to improve the social support of women. (目的 调查孕妇对分娩的恐惧感以及个体因素对其影响程度, 分析孕妇分娩恐惧与社会支持的相关性。方法 采用方便抽样选取住院的101名孕妇为研究对象, 收集孕妇一般资料和产科相关资料, 和使用分娩恐惧量表(CAQ)调查孕妇对分娩的恐惧感, 使用领悟社会支持量表(PSSS)调查孕妇社会支持程度。结果 CAQ量表4个维度中胎儿健康维度得分较高。不同职业的孕妇中文版CAQ总分差异有统计学意义(P＜0. 01)。社会支持与孕妇分娩恐惧之间缺乏相关性。结论 孕妇对胎儿健康的关注度高于其本身, 孕妇的职业状况影响孕妇对分娩的恐惧感。应制定针对性干预措施提升孕妇社会支持。)

Chengdao Oilfield is located in the modern Yellow River underwater delta, where the seabed strata are complex, and the sediment silt and silty clay have great interbedding changes. In recent years, an increasing number of jack-ups are installed and removed in the same wellhead or similar wellhead. There are risks of sliding pile, punch-through, and liquefaction and subsidence in the area where piles are repeatedly inserted and pulled out on offshore moving platform. Aimed at the risks, preventive measures are analyzed to reduce the risk of pile driving on jack-up platforms.

In the course of towing of offshore platform, it is of great significance to calculate the towing resistance ahead of time and select the main tugboat with proper power for towing safety. In this paper, the calculation formulas or recommended methods for towing resistance of mainstream classification societies were investigated, and a CFD/AQWA finite element numerical simulation was conducted for the typical jack-up offshore platform in Shengli Petroleum Engineering Company.Based on the comparative analysis of the results, a suitable model for the calculation of towing resistance of platforms in domestic waters was optimized, and a suitable towing factor of safety was proposed.

For widely applying Fe17Mn5Si10Cr5Ni memory alloy pipe joints in the connection and repair of seawater pipelines，the corrosion behaviors and mechanism of Fe17Mn5Si10Cr5Ni memory alloy in artificial seawater were analyzed by electrochemical test，corrosion surface analysis technology and corrosion product analysis technology.Results showed that Fe17Mn5Si10Cr5Ni memory alloy could undergo electrochemical corrosion in artificial seawater，and its self-corrosion potential at 3 h was -0.185 V.The self-corrosion potential decreased gradually with the increase of corrosion time，and the corrosion form of Fe17Mn5Si10Cr5Ni memory alloy in artificial seawater was pitting corrosion.Furthermore，the corrosion products were black brown and loose，with a poor adhesion and low bonding strength with the substrate.The corrosion products were Fe2O3，Fe3O4 and FeO(OH).

A multiplex ligation-dependent probe amplification (MLPA) technique was developed for simultaneous detection of six food allergens: soy, sesame, peanut, almond, hazelnut and walnut. Six pairs of species-specific MLPA probes targeting the internal transcribed spacer (ITS) sequences were designed and synthesized. The probes were hybridized with the target DNA, ligated and amplified by polymerase chain reaction (PCR) and the amplicons were detected using capillary electrophoresis, revealing that they could clearly discriminate the six food allergens. Good specificity of the MLPA system was observed for more than 20 plants, animals and bacteria. The limit of detection (LOD) of the assay was determined to be 5 mg/kg for model cookie spiked with different concentrations of the target species. The applicability of the MLPA assay was demonstrated through the analysis of 30 different commercial products, evidencing good performance in practical applications. Therefore, the MLPA technique is highly specific and sensitive and can provide technical support for the assessment, label management and risk control of food allergens.

Dysphonia analysis of Parkinson’s disease is the basis of information analysis for early diagnosis of Parkinson’s disease based on speech. In recent years, with the deepening of research, Mel transform domain information shows more and more advantages in this field. At the same time, the improvement of classification performance by extracting structural features is increasingly apparent. This paper proposes a method for local gradient statistical feature extraction in Mel transform domain from the point of the structure of Mel transform domain information of speech signals of people with Parkinson’s disease. Firstly, the speech signal is converted into the energy signal in the time-frequency transform domain by the method of Mel frequency transformation, and the energy spectrum is represented visually. Then, the energy data are processed by sliding window, and the local structure information of the Mel transform domain is obtained by calculating the gradient and angle of each energy point in the detection window. Finally, the gradients of the energy points of all detection windows are calculated according to the angles to obtain the local gradient statistical features, which represent the change of energy value in Mel transform domain. The results of the experiments performed on different datasets by different classifiers show that compared with the methods of Mel transform domain analysis, cepstrum analysis and deep learning, the local gradient statistical features in Mel transform domain are superior to them in classification accuracy and sensitivity, thereby verifying the effectiveness of the local gradient statistical feature in the dysphonia analysis of Parkinson’s disease.

In order to provide a basis for the design and application of carbon fiber reinforced resin matrix composites and aiming at the galvanic corrosion between carbon fiber composite materials and metals, the influences of CFRP type, metal material type, service environment and structural connection method on the above - mentioned galvanic corrosion were expounded based on the microstructure and performance characteristics of the carbon fiber and its composite materials. As the riveting, bolting and bonding between carbon fiber composite materials and metals could have different effects on the galvanic corrosion and there is little research on this aspect at present, this will be one of the important study contents in the future.

For slowing down the internal corrosion in crude oil pipeline, the failure mode, morphology and mechanism, as well as influence factors of internal corrosion in buried pipeline transporting purified crude oil were researched systematically. Results showed that the aqueous phase was deposited gradually in some locations during transport, and Cl - content could reach the maximum of 48 859.8 mg/L. In addition, the internal corrosion was mainly pitting and localized corrosion, and during the autocatalytic process of internal corrosion, the continuous migration of Cl - into the pits promoted the development of pitting corrosion, thus the Cl content at the pit bottom was higher than that at the surface by up to one order of magnitude. When the water content of the pipeline fluctuated in the range of 0.1% to 3.9%, the water content possessed little effect on the risk point of internal corrosion, and increasing the medium flow velocity had a more obvious effect on reducing the risk of internal corrosion. When the flow velocity increased to 2.00 m/s, the number of locations at risk of internal corrosion was reduced by 35.23% compared with that when actual flow velocity was 0.29 m/s.

In order to study the relationship between the macro-bending loss characteristics of the single-mode fiber and the temperature change, the thermo-optical effect and thermal expansion effect are corrected according to the theoretical formula proposed by Faustini L. Based on this formula, the macro-bending loss of SMF28 and 1060XP single-mode fiber with core-cladding-infinite coating structure under the influence of temperature is simulated and analyzed. The influence of temperature, wavelength, bending radius and other factors on the macro-bending loss of SMF28 single-mode fiber is explored, and the linear fitting results between the temperature and the two kinds of single-mode fibers are obtained. The results show that the macrobending loss increases with the decrease of bending radius, and the increase of wavelength. The loss also decreases with the increase of temperature. Under certain bending radius and wavelength, the macro-bending loss and temperature are in monotonic relationship, which means increasing the number of bending turns can effectively increase the sensitivity to temperature.

AbstractObjective: To investigate the effect of γδ T cells on the proliferation, apoptosis and autophagy of multiple myeloma cells., Methods: Peripheral blood mononuclear cells (PBMNC) were isolated from healthy volunteers, and stimulated with zoledronic acid (Zol) in combination with rhIL-2. Flow cytometry analysis was used to detected the purity of γδ T cells. γδ T cells were collected and co-cultured with RPMI-8226 or U-266 cells at different effector target ratios. The proliferation of RPMI-8226 or U-266 cell lines were detected by CCK-8. Cell cycle and cell apoptosis were detected by flow cytometry and Western blot．The expressions of autophagy-related proteins were detected by Western blot., Results: γδ T cells can be expanded in vitro. γδ T cells could inhibit the proliferation of RPMI-8226 or U-266 cells, induced cell cycle arrest and promoted apoptosis in an effector target-dependent manner. In addition, γδ T cells could induce autophagy of myeloma cells, inhibited the expression of autophagy-related PI3K, P-AKT and P-mTOR, while increased the expression of AMPK and Beclin-1., Conclusion: γδ T cells can inhibit the proliferation of RPMI-8226 and U-266 myeloma cells, induce cell cycle arrest, promote apoptosis, and enhance autophagy in vitro. The mechanism may be related to inhibition of PI3K/AKT/mTOR signaling pathway and/or activation of AMPK/Beclin-1 signaling pathway.