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In order to analyze the factors affecting yolk blackening in salted duck eggs, this study investigated the differences in the color difference, metal ion contents and proteomics in different parts of normal and black-yolked salted duck eggs. The effects of these factors on the degree and rate of yolk blackening were studied by single factor experiments. The results showed that the higher the contents of Fe and Cu, the smaller the color difference value of yolk and the blacker the color. It was speculated that the sulfide formed by the combination of Fe2+ in phosvitin (Pv) and S2- was responsible for the blackening of egg yolk, and the degradation and desulfurization of cysteine was an important contributor to sulfur production in egg yolk. Microbial load, temperature and pH were important factors affecting yolk blackening. With increasing bacterial load and curing temperature of duck eggs, the rate of yolk blackening increased. H2S was produced in the pH range of 7.0–8.0, and the gas production rate was the fastest at pH 7.5. In summary, it can be inferred that yolk blackening in salted duck eggs is caused by the discoloration reaction between sulfur and iron elements in egg yolk. Curing temperature, pH and the bacterial load of duck eggs have a great influence on yolk blackening.

The geological conditions of the North China-type coalfields are complicated, and a large number of water-conducting channels are formed by the tectonic cutting of the coal seam base plate, whose detection and identification have always been the key point and difficulty in water damage prevention and control. Based on the multi-branch directional long drilling overrun investigation, the water-conducting channel identification technology combining process analysis and fuzzy comprehensive evaluation was constructed. Firstly, in the process of overpassing exploration, six evaluation indexes were selected, named drilling time recording, drilling fluid consumption, γ recording, rock chip recording, water pressure test and injectability and the construction process was divided into 16 working conditions, according to which a comprehensive analysis flowchart was set up to make a qualitatively judgement on whether the sample points were water-conducting. Secondly, the six indicators are quantified and graded by drilling speed, drilling fluid consumption, γ value, non-tuff proportion, unit grouting volume, and grouting volume, the weights of the indicators were determined by using the over-weighting method, and a three-level quantitative identification was made based on the fuzzy theory and the maximum membership principle to determine whether the sample point was water-conducting. Lastly, the technique was used to carry out a comprehensive process analysis and fuzzy comprehensive evaluation of 13 points in the 15031 working face of Zhaogu No.1 mine, of which 10 points had a high probability of water conduction and 3 points had a low probability of water conduction. This technique constructed a system of indicators for identifying water-conducting channels, and carried out quantitative grading and comprehensive evaluation, which improved the identification of water-conducting channels in the coalbed base plate.

Metal organic frameworks(MOFs),as non-homogeneous Fenton oxidation catalysts,are difficult to be utilized multiple times and prone to secondary pollution in the treatment of printing and dyeing wastewater. To solve this problem, metal organic framework polypropylene melt blown composites (TA-APTES@MOF@PP) were prepared by modifying the surface of polypropylene melt blown nonwoven (PP) with polyphenol heterogeneous network coating, which resulted in excellent adhesion and secondary reactivity,and by in situ growth of MIL-88B (Fe) crystals on its surface. The catalytic degradation effect and recycling performance of the composites were tested with methylene blue dye (MB) as the target pollutant,and the catalyst delivery ratio and optimal reaction conditions were determined by single-factor optimization. The results showed that the degradation of MB by TA-APTES@MOF@PP (MOF 20 mg) under dark conditions was optimal at 3 h with a degradation rate of 95.3% when the pH of dye solution was 3 and the H2O2 concentration was 50 mmol/L. The composite material has no secondary pollution,easy to recycle, good stability, acid and alkali resistance, catalytic effect in the pH range of 2-11 of dying solution, and the 3 h degradation rate was still above 73.4% after 5 cycles. The composite material had a broad application prospect in printing and dyeing wastewater treatment and water environment management.

With the increase of mine development depth, the problems such as high difficulty in plugging deep water inrush points and large quantities of work have become increasingly prominent. The surface multi branch horizontal directional drilling technology is an effective means to solve the above problems, and its construction technical difficulties are mainly well trajectory control, well wall stability control and grouting effect improvement. Based on the above problems, taking Wucun Mine in Jiaozuo Mining Area as an example, the optimal plugging scheme for water inrush points is proposed. The structure of PDM drill is improved by adding eccentric cushion block to improve the control of well trajectory; the potassium ammonium based polymer drilling fluid system is used to optimize the proportioning scheme of the treating agent to improve the wellbore stability control; variable frequency speed regulating grouting pump and secondary mixing process are adopted to improve the grouting effect. The results show that the maximum drop of water level in Wucun Mine shaft is 6.53 m after the completion of the project, and the water blocking effect is significant.

Amide bond is a ubiquitous and crucial functional group that serves as the linchpin for constructing proteins, peptides, and is also the central site in numerous drug molecules. Consequently, it is crucial to investigate the strategies and mechanisms of amidation reactions. In recent years, the use of electrochemistry for amidation has gained significant attention due to its exceptional qualities such as increased selectivity and eco-friendliness. However, due to the complexities of the reaction processes and the scarcity of relevant analytical tools, the studys of in-situ monitoring and mechanistic investigations on these electrochemical amidation reactions are rare. In response to this challenge, a novel coupling device was designed in this study. The main component of the coupling device was a glass capillary tube with a metal cover. The metal coating on the tip's outer surface was connected to a high voltage power supply to drive the electrospray ionization process. Additionally, the metal coating inside the tip was also connected to the metal coating on the tip's outer surface and served as the working electrode for an electrochemical reaction. When high voltage was applied, both the electrospray process and the electrochemical reaction on the tip could be driven simultaneously. The substances produced by the electrochemical reaction in the capillary tip could be quickly transfered to spray droplets, ionized via desolvation process, and finally detected via mass spectrometry. Based on this technique, a series of aromatic primary amines amidation reactions were observed in situ while using triphenylphosphine as the condensing agent. Numerous important intermediates were also discovered during these reactions. Remarkably, this novel approach not only facilitated continuous real-time monitoring of these reactions but also empowered scientists to unambiguously identify an array of key intermediates, including the elusive short-lived free radical intermediates. The electrochemical-mass spectrometry coupling device has numerous advantages, including short analysis delays, the ethical use of sample resources, and uncomplicated, simple preparation processes. It's potential to revolutionize the field of electroorganic synthesis reactions. This cutting-edge technique is poised to become an invaluable tool for rapid screening and in-depth investigations into the complex mechanisms of driving amidation reactions. The coupling device represents an exciting improvement forward in the context of drug investigations, where precision and efficiency are critical. Additionally, as society places increasing emphasis on environmental sustainability and the demand for precise chemical processes intensifies, this breakthrough coupling device is expected to become a formidable instrument in investigating the mechanism of electrochemical reactions.

In the novel power system of urban grid, the multiple resources increase and the data collection becomes more difficult, which lead to a higher random missing data rate. It is difficult to meet the demand for refined analysis and decision making. For the frequent missing data problem in the distribution network, a new missing data filling method for power systems based on fluctuation cross-correlation analysis (FCCA) and generative adversarial network (GAN) is proposed in this paper. Firstly, a multi-dimensional feature extraction method for strongly correlated grid data is proposed by fusing FCCA. Secondly, based on kernel principal component analysis (KPCA), the multi-dimensional feature dataset is dimensionally reduced. Finally, an improved GAN structure is designed, which integrates multi-dimensional features of power grid equipment data to reconstruct low dimensional vectors. The missing data is accurately filled in, and the integrity and availability of the new power system measurement data is improved. The algorithm is validated using real grid data, and the proposed method is also tested in a city grid. The results show that the proposed method has higher filling accuracy than the traditional data filling methods. Therefore, it is conformed that in the case of continuous and significant data environment, integrating strong correlation features for data filling has significant advantages in improving the integrity and availability of measurement data.

Objective To investigate the role and molecular mechanism of poly (ADP-ribose) polymerase 1 (PARP1) in mitosis of HeLa cells. Methods Flow cytometry, immunofluorescent assay and live cell imaging were used to detect the effect of PARP1 on mitosis of HeLa cells. Chromosome karyotype analysis and immunofluorescent assay were used to detect the effect of PARP1 on chromosome stability. Western blotting and co-immunoprecipitation assay were used to analyze the protein expression and enzyme activity of PARP1 in HeLa cells during mitosis. Proteome mass spectrometry was used to identify proteins that interacted specifically with PARP1 in mitosis, which was verified by co-immunoprecipitation and poly(ADP-ribosyl)ation assay. Results Flow cytometry and immunofluorescence staining showed that the response of HeLa cells to nocodazole-induced mitotic arrest was significantly decreased after genetic manipulation (knockdown) or pharmacological inhibition (olaparib) of PARP1 (P < 0.05). The results of live cell imaging showed the mean mitotic time of HeLa cells was shortened after the knockdown of PARP1(P < 0.01). Chromosome karyotype analysis and immunofluorescence staining showed that the proportion of aneuploid and multipolar spindle cells was increased significantly after the knockdown of PARP1 (P < 0.05). Western blotting showed no significant difference in the protein level of PARP1 during the process of mitosis, while the co-immunoprecipitation assay showed the enzyme activity was increased significantly. Proteome mass spectrometry and co-immunoprecipitation assay showed that PARP1 specifically interacted with BUB3, a major component of the mitotic checkpoint complex (MCC), and BUB3 is poly(ADP-ribosyl)ated in mitosis. Conclusion DNA damage repair protein PARP1 may regulate the mitosis of HeLa cells and maintain its chromosome stability by upregulating enzyme activity and poly(ADP-ribosyl)ating mitotic BUB3.

Objective To explore the mechanism of FGFR3⁃TACC3 (F3⁃T3) fusion gene mediating DNA damage repair through promoting pyruvate kinase M2 (PKM2)'s nuclear translocation in glioblastoma. Methods The lentiviral transfection technology was used to constructed stable transitional cell lines U87MG cells and U251MG cells that stably expressing F3 ⁃ T3 and empty vector. In vivo glioblastoma model was constructed by intracranial in situ tumor implantation in athymic mice, and the tumorigenic ability of F3⁃T3 transfected cells in athymic mice of each treatment group was observed by small⁃animal in vivo imaging system. Bioinformatics analysis was performed to analyze gene microarray data exploring the possible biological functions of F3 ⁃ T3 mediating chemoresistance and identify the relationship between survival expectations and PKM2 expression levels in glioblastoma patients from The Cancer Genome Atlas (TCGA) database. Transient transfection of small interference RNA (siRNA) was used to knock down the expression of PKM2 in the F3 ⁃ T3 transfected cells. Proliferative activity of U87MG and U251MG cells treated with different concentrations of temozolomide (TMZ), transfected with siRNA, and TMZ in combination with Compound 3k, a PKM2 inhibitor, was observed in CCK ⁃ 8 cell proliferation assays. Nuclear and cytoplasmic proteins were extracted separately and PKM2 protein expression was observed in whole cell extract, cytoplasmic extract and cytosolic extract after TMZ treatment. Relative expression of PKM2, relative expression of cytosolic phosphorylated histone H2AX (p⁃H2AX) and relative expression of siRNA knockdown PKM2 gene in U87MG and U251MG cells stably expressing the F3 ⁃ T3 fusion gene, detected by Western blotting. Results 1) CCK⁃8 cell proliferation assay showed that the survival rate of U87MG cells in the F3 ⁃ T3 transfected group was higher than that in the empty vector transfected group after treatment with TMZ 640, 320, 160, 80, 40 μmol/L (P = 0.000, 0.000, 0.000, 0.000, 0.004, 0.010), and the survival rate of U251MG cells in the F3 ⁃ T3 transfected group was also higher than that in the empty vector transfected group after TMZ 640, 320, 160, 80, 40, 20, 5 μmol/L (P = 0.000, 0.000, 0.000, 0.002, 0.001, 0.002); the survial rate of U87MG cells in the si⁃PKM2⁃1009 transfected group was lower than that of F3 ⁃ T3 transfected group after TMZ 640, 320, 160, 80, 40, 20, 10, 5, 2.50 μmol/L, the survival rate of U251MG cells in the si⁃PKM2⁃1377 transfected group was also lower than that in F3⁃T3 transfected group after TMZ 640, 320, 160, 80, 40, 20, 5 μmol/L (P = 0.000, 0.000, 0.002, 0.000, 0.002, 0.048, 0.042); and the survival rate of U87MG cells in TMZ + Compound 3k group was lower than TMZ group after TMZ 640, 320, 160, 80, 40, 20 μmol/L (P = 0.000, 0.000, 0.000, 0.000, 0.001, 0.002), and the survival rate of U251MG cells in TMZ + Compound 3k group after treatment with high concentrations of TMZ (640, 320, 160, 80 and 40 μmol/L) was also lower than TMZ group (P = 0.000, 0.000, 0.000, 0.000, 0.003), while the survival rate of U251MG cells in TMZ + Compound 3k group after treatment with low concentrations of TMZ (10, 5 and 2.50 μmol/L) was higher than that of TMZ group (P = 0.000, 0.000, 0.006). 2) An animal model of glioblastoma showed the presence of TMZ resistance in homozygous mice. 3) Bioinformatic analysis showed that the biological function of F3⁃T3 was significantly enriched in the DNA repair pathway (P = 0.000). Survival and overall survival of glioblastoma patients in the TCGA database were lower in the PKM2 high expression group than in the low expression group (P < 0.05). 4) Western blotting showed that the relative expression of p⁃H2AX in U87MG (P = 0.000, 0.000, 0.004) and U251MG (P = 0.000, 0.007, 0.005) cells in the F3 ⁃ T3 transfected group were lower than those in the empty vector transfected group after TMZ treatment for 48 h and then medium change for 24, 36 and 48 h. PKM2 protein incorporation into the nucleus was observed in both U87MG and U251MG cells in the F3⁃T3 transfected group after TMZ treatment, whereas it was not observed in cells in the empty vector transfected group; si⁃PKM2⁃1009 and si⁃ PKM2⁃1377 knocked down the relative expression of p⁃H2AX in U87MG (P = 0.000, 0.001, 0.006) and U251MG (P = 0.000, 0.000, 0.000) cells, respectively. Conclusions In the presence of TMZ, F3 ⁃ T3 promotes PKM2's nuclear translocation and activates DNA damage repair pathways, which in the eventually results resistance of glioblastoma cell to TMZ. PKM2 inhibitors can compromise the resistance glioblastoma cells stably expressing F3⁃T3 fusion gene to TMZ.

Short chain fatty acid (SCFA), a class of fatty acids with six or less carbon atoms, have important physiological functions for human health. As metabolites of the intestinal flora, SCFA can maintain intestinal health. Furthermore, accumulating research has proved that SCFA have many functions such as maintaining brain and bone functions, participating in regulating the immune response, antibacterial and antitumor activity, and alleviating obesity and diabetes. In this paper, recent literature on the production, absorption and functions of SCFA in the body are reviewed to provide a theoretical reference for the research and application of SCFA in nutrition.

After comparing the bacterial load of black-yolked salted duck eggs (BSE) and that of duck eggs with different cleanliness degrees, it was found that the total bacterial count on the shell of severely stained eggs (DE) was distinctly higher than that on the shell of non-visually stained eggs (CE), and the total bacterial count in the shell membrane and contents of BSE increased greatly. Furthermore, 16S rDNA gene sequencing was used to analyze the differences in the composition and abundance of bacterial communities in CE, DE and BSE. It turned out that Proteobacteria, Firmicutes and Actinobacteria were the dominant phyla, accounting for 34.35%, 27.25% and 17.28% of the total abundance, respectively, while Bacteroidetes accounted for 8.29% of the total abundance. Proteobacteria was the dominant bacteria in DE and accounted for 89.01% of the total abundance, while the relative abundance of Firmicutes and Actinobacteria were 6.16% and 3.98%. The dominant phyla in BSE were Proteobacteria (76.50%), Bacteroidetes (8.00%), Actinobacteria (6.76%) and Firmicutes (5.43%). The abundance of Proteobacteria in DE and BSE was significantly increased. The dominant bacterial genera in CE were Nesterdella (9.08%), Campylobacter (7.91%), Streptococcus (3.41%) and Oligomonas (2.92%). In DE, Psychrobacter was the dominant genus, accounting for 86.01% of the total abundance, and the relative abundance of Acinetobacter was 2.20%. The dominant bacteria in BSE were Rolstonia (22.91%), Serratia (5.05%) and Actinomycetes (3.32%). The cluster analysis of bacterial diversity showed that the dominant microorganisms of BSE were close to those of DE. The microbial phenotype analysis showed that the dominant microorganisms of BSE were Gram-negative bacteria, had high oxidative stress tolerance and pathogenicity, and could tolerate oxidizing detergents. The results of microbial gene function prediction and species composition of metabolic pathways demonstrated that bacterial carbohydrate decomposition, lipid transport and metabolic oxidation in DE were stronger than those in CE. More coenzyme transport and metabolic pathways could make the biochemical reactions of bacteria from DE faster to produce more secondary metabolites, thus resulting in changes in the quality of duck eggs. This is consistent with the highest bacterial abundance in the secondary metabolite biosynthesis, transport and catabolism pathways in BSE. The results of this study provide theoretical support for the cleaner production of duck eggs.

ObjectiveTo sort out and analyze the research progress of adolescent psychological resilience， and to grasp the research hotspots and frontiers in this field.MethodsCiteSpace was used to make a visual analysis of the number of publications， authors and institution， and co-occurrence， clustering and burst terms of keywords in literatures related to adolescent psychological resilience collected in CNKI database from January 1， 2012 to December 31， 2021.Results① For almost a decade， the research on adolescent psychological resilience was divided into a slow growth stage （2012-2018） and a rapid growth stage （2018-2021）. ② The cooperation between authors were relatively close， and most of them were small and medium-sized cooperative organizations. There was less cooperation in scientific research institutions and most of them were normal universities. ③ In terms of co-occurrence analysis， hot keywords could be roughly divided into three categories： mental health status， influencing factors， and prevention and intervention research. ④ The related high-frequency keywords generate ten clusters， including academic emotions， learning burnout， adolescents， migrant children， mental health， internalized problems， social support， coping style， self-esteem and happiness. ⑤ The keywords with high burst intensity were coping style， mental health， mediation， regression analysis， social work， mental health and anxiety.ConclusionIn the future， cooperation between research institutions can be strengthened to improve the quality of the research on psychological resilience of adolescents. In addition， intervention research related to psychological resilience may become a hotspot in this field in the future.

ObjectiveTo investigate the mediating role of loneliness and social anxiety in the relationship between basic psychological needs satisfaction and smartphone addiction among high school students， and to provide references for the intervention to smartphone addiction for high school students.MethodsIn April 2022， a total of 14 666 high school students from 5 middle schools in a county of Sichuan Province were included by random sampling method. Basic Psychological Needs Scales （BPNS）， the UCLA Loneliness Scale-3 edition （UCLA-3）， Interaction Anxiousness Scale （IAS） and the Mobile Phone Addiction Index （MPAI） were used for cross-sectional investigation. Bootstrap method was used to analyze the mediating role of loneliness and social anxiety in the relationship between the basic psychological needs satisfaction and smartphone addiction.Results① In this study， 14 036 valid questionnaires were returned， and 1 752 （12.48%， 95% CI： 0.114~0.136） high school students were found to be addicted to smartphone phone. The BPNS score was negatively correlated with UCLA-3， IAS and MPAI scores （r=-0.771， -0.486， -0.417， P

Parahydrogen-induced polarization (PHIP) technique can greatly enhance the sensitivity of nuclear magnetic resonance (NMR) signals, and has been applied in the fields of magnetic resonance imaging, in situ chemical reaction monitoring, etc. In addition to improving the sensitivity of different molecules in the PHIP, it is also crucial to extend and preserve the high polarization state. To achieve this, a possible approach is to transfer the polarized state into a nuclear spin singlet state. Here, we focus on the singlet states preparation in hexene molecule that can be polarized by PHIP. By designing optimal control pulses, a five-spin system in hexene molecule was manipulated, and various quantum states were prepared respectively. Our results show that three different nuclear spin singlet states could be prepared with the group CH2=CH- in hexene. The three different nuclear spin singlet states have longer lifetime than that of the initial state polarized by PHIP, and thus can be utilized as the intermediate states to delay the decay of the polarization state. By comparing the lifetime of the singlet state with the longitudinal relaxation time of the corresponding spin, it is deduced that converting the state of the polarized hexene to longitudinal magnetization may also be an effective way to preserve the polarizability.

Objective To investigate the outcomes of a novel direct pulp capping agent containing platelet-rich fibrin (PRF) and mineral trioxide aggregate (MTA). Methods A total of 32 New Zealand rabbits were randomly divided into 4 groups, namely, the PRF+MTA group (P+M group), PRF group (P group), MTA group (M group) and blank control group (BC group), with 8 rabbits per group. Dental pulp exposure and direct pulp capping were performed, and complete crown square sealing was performed on 2 mandibular central incisor teeth of each rabbit. Four rabbits from each group were euthanized after each observation period (7 and 28 days). The experimental teeth were subjected to HE staining. Inflammatory cell infiltration, calcified bridge formation and pulp tissue disorganization were observed and graded. Results Inflammatory cell infiltration: on the 7th day, group P+M and group M were lighter than group BC (P0.05). Calcified bridge formation: on the 7th and 28th days, group P+M was lighter than group P, group M and group BC (P0.05). Conclusion The combination of PRF and MTA for direct pulp capping provided light inflammatory cell infiltration, stable pulp status and a strong ability of pulp tissue to form calcified bridge, and the calcified bridge resembled certain points of osteodentin.

ObjectiveTo establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy.MethodsThe collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types.ResultsAccording to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy.ConclusionThree-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.

The quality of naturally fermented maize flour, unfermented maize flour and maize flour fermented with Lactobacillus plantarum (Lp) and/or Saccharomyces cerevisiae (Sc) was analyzed by using unfermented maize flour as the control. The results showed that the contents of crude protein, crude fat, crude fiber and crude ash in fermented maize flour were significantly lower (P < 0.05) and the content of total starch was significantly higher (P < 0.05) when compared with unfermented maize flour. Fermentation increased the pasting temperature of maize flour significantly (P < 0.05), the breakdown and setback values of naturally fermented and Lp + Sc fermented maize flour were significantly lower than those of unfermented maize flour (P < 0.05), and the stability and anti-retrogradation ability of maize flour were improved. Moreover, fermentation with Lp and Lp + Sc had a pronounced effect on the structure of maize flour, while during fermentation with Sc and Lp + Sc, aroma compounds and metabolites which could improve the off-odor of fermented maize flour were produced. The fermentation periods of maize flour with Lp, Sc and their combination were 72, 18?and 48?hours, respectively compared to 13 days for natural fermentation. Maize flour fermented with Lp + Sc had better quality, flavor and processing properties.

Objective To explore the influencing factors of intracranial infection in patients after ventricular drainage, and to build and verify the established risk prediction model. Methods A retrospective analysis was carried out on 757 patients who underwent external ventricular drainage (EVD) in our department from January 2010 to December 2018. According to the occurrence of postoperative intracranial infection, they were divided into intracranial infection group (n=79) and non-intracranial infection group (n=678). Their clinical data were collected and compared. Univariate analysis and multivariate logistic regression analysis were used to explore the influencing factors of intracranial infection after ventricular drainage. A risk prediction model was established and anomogram was drawn. Another 148 patients with EVD in our hospital from 2019 to 2020 were selected as the validation group, including 8 patients with intracranial infection after surgery and 140 patients without. The area under receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were employed to evaluate the prediction efficacy of the model. Results Hypoproteinemia, lumbar cisternae drainage, EVD time >7 d, pulmonary infection, tracheotomy, open craniocerebral trauma, surgical incision infection, and complicated with bacteremia/sepsis were influencing factors of intracranial infection after EVD. The validation results for the prediction model showed that the area under ROC curve for the risk of postoperative intracranial infection was 0.923 in the modeling group and 0.920 in the verification sample (P < 0.01). As to the Hosmer-Lemeshow test, the P value was 0.450 in the modeling patients and 0.877 in those from the verification group. Conclusion There are 8 high-risk factors for incidence of intracranial infection in patients after EVD. Our established model can effectively predict the occurrence of intracranial infection in these patients.

This paper summarized the nursing cooperation in transurethral resection of prostate under comprehensive body temperature control. The clinical data of 80 patients who received transurethral resection of prostate were retrospectively analyzed. The comprehensive body temperature control strategy was carried, including adequate preoperative preparation and targeted nursing interventions during operation. There was no intraoperative hypothermia or massive hemorrhage reported, and patient’s blood pressure was stable during the surgery. Based on perioperative nursing cooperation, adopting comprehensive body temperature control showed a positive effect on reducing the risk of intraoperative hypothermia and postoperative complications. (总结综合控温干预下经尿道前列腺电切术的护理配合。回顾医院2021年12月—2022年12月收治的经尿道前列腺电切术治疗的80例患者的临床资料。采取综合控温措施实施干预, 包括充分的术前准备, 术中针对性护理措施。患者术中无低体温发生, 无大出血, 血压平稳, 手术顺利进行, 术后无相关并发症。对经尿道前列腺电切术患者采取综合控温干预措施, 同时完善围手术期护理, 对降低术中低体温和术后相关并发症发生风险具有积极意义。)

Objective To explore the "clinical normal reference range" of pulpal blood flow (PBF) in the physiological state in an effort to provide a reference for clinical diagnosis and treatment. Methods According to the working principle and operational considerations of laser Doppler flowmetry (LDF), the PBF blood flow value of the first molars of the upper and lower mandibles of normal adults was detected by LDF, and the clinical reference value range under physiological conditions was analyzed and calculated. The differences in PBF values by sex, dental position and location (left and right side, upper and lower jaw) were analyzed. Results A total of 200 normal adult participants with an average age of (22.76 ± 3.26) years were included. The cohort included 95 males and 105 females, with a total of 800 first molars. Neither the PBF values of the left and right first molars nor the PBF values of the upper and lower first molars in males or females significantly differed (P>0.05). The PBF value for females was higher than that of males. Specifically, the clinical reference PBF values for males and females were (8.56 ± 3.25) PU and (9.51 ± 3.47) PU, respectively. Conclusion The PBF values of normal adult first molars in healthy subjects were higher in females than in males, and in the PBF values of first molars of the same sex did not significantly differ between the left side and right side or upper and lower jaw; these values could be used as a reference for the selection of control teeth.

Objective To investigate the effects of JSH⁃23 combined with Stattic targeting inhibition of nuclear factor⁃κB (NF⁃κB) and signal transducer and activator of transcription factor 3 (STAT3) signaling pathways on the proliferation and migration ability of mesenchymal glioblastoma cells and the expressions of NF⁃κB pathway and STAT3 pathway⁃related proteins. Methods The mRNA⁃seq results of 529 glioma patients were downloaded from The Cancer Genome Atlas (TCGA). Bioinformatics was used to analyze the correlation between RelA/P65 and STAT3 and the markers of mesenchymal glioblastoma, as well as the expression of NF⁃κB pathway and STAT3 pathway⁃related proteins in mesenchymal, classical and proneural glioblastoma. The human glioma cell lines U87MG and U251MG in vitro were treated with JSH⁃23, Stattic, JSH⁃23 and Stattic, respectively. The half⁃inhibitory concentration (IC50) of the two drugs was calculated by cytotoxicity assay, and the synergistic effect of the two drugs was observed by drug synergistic assay. CCK⁃8 assay and colony⁃forming assay were used to detect the proliferation activity of tumor cells. Wound healing assay and Transwell assay were used to detect the migration ability of tumor cells. Western blotting was used to detect the relative expressions of NF⁃κB pathway and STAT3 pathway⁃related proteins P65, phosphorylated P65 (p⁃P65), STAT3, phosphorylated STAT3 (p⁃STAT3) and CD44. Results 1) Bioinformatics analysis showed that RelA/P65 mRNA and STAT3 mRNA were positively correlated with mesenchymal glioblastoma markers CD44, CXCR4, CHI3L1, IL⁃4R and TRADD (r=0.206-0.605; P＜0.01, for all); the expressions of NF⁃κB pathway and STAT3 pathway⁃related proteins in mesenchymal glioblastoma were the highest, followed by classical glioblastoma, and the lowest in proneural glioblastoma. 2) The cytotoxicity assay showed the IC50 of JSH⁃23 on U87MG and U251MG cells were 59.39 and 56.21 μmol/L, and Stattic were 0.96 and 1.08 μmol/L. The drug synergistic assay showed that the synergistic effect of JSH⁃23 at 40-80 μmol/L and Stattic at 0.50-1 μmol/L on U87MG was the highest, and the synergistic effect of JSH⁃23 at 40 μmol/L and Stattic at 1 μmol/L on U251MG was the highest. The final concentration of JSH⁃23 was 60 μmol/L and Stattic was 1 μmol/L. 3) After the combined treatment of JSH⁃23, Stattic, JSH⁃23 and Stattic, the proliferation activity of U87MG and U251MG cells decreased (P=0.000, for all), the colony forming efficiency decreased (P=0.000, for all), the cell mobility decreased (P＜0.05, for all), and the positive cell numbers of crystal violet staining decreased (P=0.000, for all). The relative expressions of P65 (P=0.000, for all), p⁃P65 (P=0.000, for all), STAT3 (P=0.000, for all), p⁃STAT3 (P=0.000, for all) and CD44 (P=0.000, for all) were decreased, especially after JSH⁃23 combined with Stattic treatment (P＜0.01, for all). Conclusions JSH⁃23 combined with Stattic targeting inhibition of NF⁃κB and STAT3 signaling pathways can effectively inhibit the proliferation and migration ability of mesenchymal glioblastoma cells, and down⁃regulate the relative expressions of NF⁃κB pathway and STAT3 pathway⁃related proteins.

Objective To explore the regularity of external-use Chinese medicine agents for curing freckle and chloasma.Methods To screening the external prescriptions for freckles and chloasma recorded in ancient books. The Excel data recording system was used to build an external prescription database of Chinese medicines for facial pigmentation skin disease. The frequency analysis and correlation analysis of 115 external prescriptions were carried out to summarize the common herbs, external application method, matrix, common Chinese medicine pairs and drug groups in the treatment of freckle and chloasma. Results Although with different causes of disease and different western medicine methods for freckles and chloasma, the external prescriptions of Chinese medicine were similar in ancient literature, Mainly including Baizhi, Baifuzi, Baiji, Bailian and Fuling, etc. Common drug pairs and drug groups included Baidingxiang, Baizhi, Baiji, Baifuzi, Bailian and Gansong, etc. The most commonly external-used method was rubbing and cleansing,with chicken egg white and honey as most popular drug matrix.Conclusion Common drugs, matrix drugs, drug pairs and external application methods for freckles and chloasma found by data mining analysis can provide ideas and references for clinical treatment and developing beauty products.

This study aims to review the biomarkers of depression discovered by proteomic techniques to guide the identification of specific biomarkers for depression. Depression is a common psychological disease， and its diagnosis and efficacy evaluation rely on subjective clinical evaluation， lacking objective diagnostic tools. Proteomics is the primary method to discover and verify biomarkers. This study reviews proteomic biomarkers in brain tissue， cerebrospinal fluid and blood of patients with depression， as well as the latest strategies for screening biomarkers of depression.

Studying the strength characteristics of slip zone soils under different shear conditions is of great significance for the stability evaluation of reservoir landslides. Aiming at the weak research on the mechanical properties of landslide zone soil in the reservoir bank accumulation layer at present, in this paper, the Tongjiaping landslide slip zone soil in the Three Gorges Reservoir area is taken as an example to research the strength variation characteristics of slip zone soils under different shear test conditions. The ARS-E2 ring shear apparatus is employed to operate the shear modes of constant velocity, acceleration and deceleration on the strength variation characteristics of the slip zone soil. The experimental results indicate that the stable residual strength of slip soil samples tends to be obtained under constant low-speed shear conditions; meanwhile, the phenomenon of 'strain softening' is prone to appearing after reaching the peak strength. Moreover, the change trend of shear stress is basically the same whether accelerated ring shear or decelerated ring shear under the same shear stress condition, which both have a positive correlation with the normal stress. However, the change in shear rate will significantly affect the peak cohesion of slip zone soils. The research results reveal the mechanical properties of the sliding zone soil under different ring shear conditions, which provide a theoretical basis for revealing the mechanical mechanism of the deformation and failure of reservoir bank accumulation landslides.

To meet the high-performance trajectory tracking requirements of underactuated autonomous underwater vehicle (AUV) under complex disturbances and parameter uncertainty, a three-dimensional trajectory tracking controller method with predefined dynamic performance and convergence time is proposed. Firstly, by extending the forward position channel of the underactuated AUV, and a multi-input multi-output trajectory tracking control-oriented model is developed. Subsequently, by combining dynamic process functions with predefined-time control theory, a dynamic performance-predefined trajectory tracking control system is established, which allows the transient quality of AUV trajectory tracking to be determined by dynamic process functions, and the actual convergence time of tracking errors to be predefined by a single control parameter. Finally, to avoid control singularities and the " differential explosion" phenomenon, the controller design incorporates the absolute value correction method and radial basis function neural network (RBFNN) fitting method. Numerical simulation results indicate that the proposed controller significantly improves the disturbance rejection and transient quality of underactuated AUV, achieving fact, smooth, and High-performance trajectory tracking. [ABSTRACT FROM AUTHOR]

Mitochondria provides most of the energy to drive cell function, and its dysfunction can lead to a variety of disease. Since mitochondria has been proved to be able to transfer between cells, mitochondrial transplantation has become an innovative idea for the treatment of mitochondrial dysfunction and this technology has been supported by evidences from animal experiments. The transplantation of mitochondrial is potentially applied in the treatment of disease of various tissues including heart, liver, lung and brain.

Coal mine production is a typical high-risk industry, and the emotional fluctuations of coal mine employees are neglected sources of danger. In order to effectively manage the coal mine employees’ unsafe emotion, the causes and induced mechanisms of unsafe emotion are analyzed. First, the complex system theory and multi-agent modeling method are used to establish coal mine employees’ unsafe emotion induction model. Second, we use the Netlogo simulation platform to dynamically simulate coal mine employees’ unsafe emotion induction process and the relationship between influencing factors. The research shows that individual psychological resilience level, social support level and event intervention strategies are negatively correlated with coal mine employees’ unsafe emotion, and unsafe affective events are positively correlated with coal mine employees’ unsafe emotion. Finally, from the three aspects of pre-job screening, employee psychological construction and safety atmosphere creation, suggestions for preventing unsafe emotion of coal mine employees are proposed.

Objective To investigate methods for predicting uric acid stones with conventional CT by measuring the CT value of stones, mean diameter size, density of stones, stone to kidney CT value ratio, and body width. Methods Patients underwent conventional CT scanning and were diagnosed postoperatively before uric acid stones and non-uric acid stones were detected by dual-energy CT.A total of 50 patients with uric acid stones and 60 patients with non-uric acid stones were enrolled, and after stones were detected by conventional CT scan, uric acid stones and non-uric acid stones were distinguished by dual-energy CT. The selected stones were ＞ 7 mm in long diameter. Data acquisition was performed on enrolled patients by a radiologist blinded to stone composition. The predictive value of each index was evaluated by independent sample t test, chi-square test, and receiver operating characteristic curve (ROC). Results There was great value in distinguishing uric acid stones from non-uric acid stones in stone CT value (P＜0.01), significant statistical difference in uniform stones or not and in size (P＜ 0.05). The CT scan showed a high predictive value for the diagnosis of uric acid stones, with AUC=0.948, sensitivity as 94%,and specificity as 85%.According to the ROC curve, the CT scaning value of 730 HU was adopted as the threshold for the diagnosis of uric acid stones, with a positive predictive value of 83.9%, a negative predictive value of 94.4%, and an accuracy of 80.1%. The size of the stone also had a predictive value, AUC=0.63, sensitivity 36%, and specificity 88.3%, and the mean diameter of the stone greater than 18.05 mm was defined as a diagnosis standard of uric acid stones according to the ROC curve, which had a positive predictive value of 72%, a negative predictive value of 62.4%, and an accuracy of 64.5%. Using a stone CT value of 730 HU as the threshold combined with a uniform stone density to predict uric acid stones, its specificity was 100% and the positive predictive value was 100%. Conclusions Conventional CT is of high value in differentiating uric acid calculi from non-uric acid calculi by measuring the mean diameter size and density of calculi. When evaluate CT result with or without homogenous stone density as the diagnostic criteria, the specificity and positive predictive value of diagnosing uric acid calculi are significantly higher.

Cellulose is one of the most abundant resources in nature. The third-generation aerogels prepared from cellulose have both the high porosity and large specific surface area of traditional aerogels and their own advantages. However, its inherent flammability, poor mechanical properties and low thermal stability limit its application. At present, the functionalization of cellulose aerogels and the development of a variety of functionalized composite aerogels have become a research hotspot. In this paper, the preparation process, functionalization methods and main application fields of cellulose aerogels are summarized. Finally, the problems of functional cellulose aerogels are discussed. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemiological trends of Alzheimer's disease in the elderly population in China from 1990 to 2019, and to provide a scientific basis for the specific formulation of prevention and treatment measures. Methods Based on data obtained from the Global Burden of Disease (GBD) 2019 database, we analyzed quantitative changes in the number of incidences and disability-adjusted life years (DALYs) of Alzheimer's disease among people aged 60 to 89 years in China from 1990 to 2019. Trend changes over the period were assessed by calculating the annual percentage change (AAPC) and linkage regression analysis, age-period-cohort models were constructed by Statal7 to analyze trends in DALY incidence and rates along three dimensions: age, period, and cohort. Results The number of DALY and Alzheimer's disease incidence cases in the Chinese elderly population in 2019 was 1 526 516 and 5 034 024 person-years, respectively, with 5 829 523 and 1 956 623 person-years of DALY and Alzheimer's disease incidence in elderly men, and 943 563 and 3 077 401 person-years of DALY and Alzheimer's disease incidence in elderly women, respectively. The Chinese elderly population in 2019 Incidence and DALY rates were 600.49 per 100 000 and 1 980.23 per 100 000, respectively, increasing at an average rate of 1.12% and 0.81% per year, with a more pronounced increase in elderly men than in elderly women. Conclusion China's elderly population faces a heavy burden of disease from Alzheimer's disease, and the government should take immediate action to alleviate the heavy morbidity and financial burden on patients. [ABSTRACT FROM AUTHOR]

In order to reduce the occurrence of coal mine safety accidents, the system dynamics(SD) method is adopted to construct an SD model of factors affecting the unsafe sentiment of miners from the miner group level, social media network level, and coal mine enterprise governance level. Vensim PLE software was used to simulate the micro-evolution trend of the influencing factors of miners’ unsafe emotions. The results show that the improvement of emotional leadership and organizational emotional carrying capacity can effectively control the unsafe sentiment of miners; coal mine enterprises should timely use the “leader persuasion effect” and “media effect” to disseminate real and effective information to control the increase of unsafe emotional intensity of miners. Therefore, coal mining enterprises should pay attention to the changes of miners’ emotions, actively manage unsafe emotions, and avoid the occurrence of safety accidents.

This paper designs a wireless measurement system based on Wave Mesh. The system uses a 26 GHz high-frequency radar-type level sensor to collect coal level data. The radar sensor automatically converts the microwave signal into a coal level signal through its own electronic circuit part, and sends the output coal level signal to the STM32F104 single-chip microprocessor for conversion and storage. The Wave Mesh wireless ad hoc network technology is used to achieve long-distance wireless transmission between the ground measurement device and the upper computer. The system application shows that the coal level measurement system can facilitate the staff to monitor the changes of the coal level in real time, adjust the switch of the coal conveyor in time, control the coal level in a normal range, and ensure the safe and normal operation of the mine.

To reduce unsafe behaviors of miners, based on affective events theory and psychological pressure theory, system dynamics(SD) method was adopted to construct the SD model of influencing factors of miners’ unsafe behaviors from the perspective of affective events. Vensim PLE software was used to conduct dynamic simulation on the mechanism of influencing factors of miners’ unsafe behaviors. The results show that: cognitive level, positive affective events and safety climate can inhibit unsafe behaviors. Psychological stress and negative affective events can promote unsafe behaviors. Therefore, coal mining enterprises should pay attention to the psychological pressure and emotion of miners, and appropriately increasing positive affective events and improving safety climate can effectively reduce unsafe behaviors of miners.

Vitamin D is an essential nutrient in the body. In recent years, increasing attention has been paid to its role in regulating immunity and anti-inflammatory effects. However, the application of vitamin D in vivo may produce some side effects, such as hypercalcemia and hypercalciuria. Some analogs of vitamin D obtained through molecular modification can reduce the side effects while retaining a similar regulatory action as that of vitamin D. The supplementation of vitamin D or the use of vitamin D analogs may contribute to the prevention and treatment of immune inflammatory diseases. This article reviews the role of vitamin D and its analogues in the prevention and treatment of oral mucosal diseases and periodontal diseases. The literature review results show that vitamin D and its analogues can protect the integrity of the oral mucosal barrier, prevent or delay the occurrence of oral lichen planus, and provide a reference value for the prevention and treatment of periodontitis.

Objective: To investigate effect of Wumei Pill on colon cell apoptosis in ulcerative colitis (UC) rats by regulating miR-146a and its mechanism. Methods: A total of 50 SD rats were selected, with 10 rats in each group, and divided into control group, model group, Wumei Pill low, medium and high doses groups. Transfected with anti-miR-NC, anti-miR-146a, miR-NC, miR-146a as anti-miR-NC group, anti-miR-146a group, Wumei Pill+miR-NC group, Wumei Pill+miR-146a group. CCK-8 was used to detect cell proliferation; flow cytometry was used to detect cell apoptosis; RT-qPCR was used to detect cell miR-146a expression; ELI-SA was used to detect cell IL-1β and IL-13 contents; Western blot was used to detect expressions of B-cell lymphoma 2 (Bcl-2) and Bax proteins. Results: Compared with control group, cell survival rate, Bcl-2 protein expression in model group were decreased, while apoptosis rate, Bax protein expression, IL-lp, IL-13 contents and miR-146a expression were increased (P<0.05). Compared with model group, Wumei Pill significantly increased cell survival rate and Bcl-2 protein expression, decreased cell apoptosis rate, Bax protein expression, IL-1β, IL-13 contents and miR-146a expression (P<0.05). Inhibition of miR-146a increased cell survival rate, Bcl-2 protein expression, decreased cell apoptosis rate, IL-1β, IL-13 contents and Bax protein expression (P<0.05). Overexpression of miR-146a reversed effects of Wumei Pills on proliferation and apoptosis of colon cells in UC rats. Conclusion: Wumei Pill can reduce apoptosis of colon cells in UC rats by up-regulating expression of miR-146a. [ABSTRACT FROM AUTHOR]

Three kinds of phenolic resin ceramic brake pads were prepared with phenolic resin, boron modified phenolic resin, melamine modified phenolic resin as binder, and ceramic fiber as reinforcing fiber. The impact toughness and hardness of the material were tested. The friction and wear properties were investigated by friction and wear tester. The worn surface morphology and its composition were analyzed by scanning electron microscope (SEM) and X-ray energy spectrometer, and the wear mechanism was also discussed. The experimental results show that boron modified phenolic resin binder can improve the hardness of friction materials, melamine modified phenolic resin can improve the impact toughness of materials, reducing material hardness; in the friction process, melamine modified phenolic resin carbonized at high temperature, forming a dense layer of friction on the surface of friction material. The existence of friction layer makes the friction coefficient of the friction material become relatively stable, and reduces the wear rate of the friction material.

The objective of this study is to clarify relay intercropping crop growth characteristics and its effects on yield formation under nitrogen application and interspecific distance. In this study, the soybean/maize strip relay intercropping system was used as the main body, to explore the crop growth rate, dry mater accumulation, and distribution, and yield differences under different nitrogen levels (nitrogen application and no nitrogen application) and interspecific distance (the spacing of soybean 30, 45, 60, 75, and 100 cm mono-cropping), to fit the process of crop dry mater accumulation, and comprehensively analyze the crop growth law and yield benefit. The results showed that the maximum growth rate of maize was reached from male stage to milking stage, and the maximum growth rate was 30 cm (MS30) without nitrogen application, which was 34.99% higher than that of monoculture maize (MM100). The growth rate of relay intercropping was significantly lower than that of monoculture soybean (SS100) before the first flowering stage, but higher than that of SS100 after the first flowering stage, with the highest spacing of 60 cm (MS60), and 78.91% higher than that of SS100 from full flowering stage to full pod stage without nitrogen application. The logistic equation could fit well the matter accumulation process of maize and soybean, and the R2 were all above 0.95. Compared with no nitrogen application, nitrogen application delayed the accumulation peak and increased the biomass of maize. The matter accumulation of intercropping soybean was slower than monoculture at the early growth stage, but MS45 and MS60 were gradually equal to or even exceeded monoculture soybean at later growth stage. Nitrogen application increased the dry matter allocation rate to the grain, and maize yield increased by 10.05% and 40.90% in two years, respectively. With the increase of interspecific distance, soybean yield increased first and then decreased, with the highest value in MS60 and the lowest value in MS30. In the two years, soybean yield in MS60 was 23.88% and 31.77% higher than MS30 under no nitrogen application and nitrogen application, respectively. The land equivalent ratio under relay intercropping was all above 1.35, among which MS60 under nitrogen application was the largest (1.89). The suitable interspecific distance (interspecific distance 60 cm) under relay intercropping can realize the cooperative growth of maize and soybean, increase crop growth rate, promote the accumulation and distribution of matter, and improve the system yield and land equivalent ratio. [ABSTRACT FROM AUTHOR]

The experiment was to screen suitable Avena sativa varieties for cultivation in the agricultural pastoral ecotone of the Qinghai Plateau. Field observations were conducted in Riyue Township, Huangyuan County, a typical agricultural pastoral ecotone of the Qinghai Plateau. A comprehensive evaluation was conducted on seven Avena sativa materials considering aspects such as production performance, nutrient composition and effective nutrient output. The results showed that Avena sativa varieties with different milk ripening stages had significant differences in the same ecological environment. The hay yield of Qingyin No.1 and Qingtian No.1 significantly higher than that of other varieties (P<0.05). The crude protein (CP) content of Mengsiyan No.1 reached up to 10.01%. The net protein utilization rate of Qingyin No.3 was the highest, reaching 58.55%, followed by Qingtian No. 1 and Qingyin No. 1. The metabolic energy and metabolic energy output of Qingyin No. 1 were the highest, reaching 10.21 MJ/kg and 10 429.35 kg/hm², respectively, with significant differences compared to other varieties (P<0.05). The CP output per unit area and net protein output of Qingtian No.1 were the highest, reaching 1 468.98 and 774.89 kg/hm², respectively, with significant differences compared to other varieties (P<0.05). The experiment indicates that based on a comprehensive evaluation of dry matter output, net protein output, and metabolic energy output, it is recommended to plant varieties Qingtian No.1 and Qingyin No.1 in this area. [ABSTRACT FROM AUTHOR]

To improve yield, effects of nano-potassium molybdate was investigated on photosynthetic characteristics and nitrogen metabolism of rapeseed. Different concentrations (0-1100 mg·L-1) of nano-potassium molybdate were sprayed on rapeseed seedling under hydroponic conditions. Changes of gas exchange parameters, key enzyme activities of carbon and N assimilation and N contents of leaves were measured. Results showed that spray of nano-potassium molybdate increased photosynthetic pigment and net photosynthetic rate of leaves, while decreased gas exchange parameters (including transpiration rate, stomatal conductance and intercellular CO2 concentration). The activities of Rubisco and PEPC enzyme increased gradually with the nano-molybdate concentration, in which Rubisco enzyme activity was significantly enhanced at 550 mg·L-1 and 1100 mg·L-1 compared to control, and PEPC enzyme activities increased significantly at 1100 mg·L-1. The activities of nitrate reductase, nitrite reductase and glutamate synthase were significantly increased at 550 mg·L-1 compared with control. No significant change was observed at higher concentrations. Nitrate-N contents were significantly reduced after the spray of nano-potassium molybdate, while ammonia-N contents and N concentrations were not significantly changed compared with control. In addition, protein content increased significantly at 550 mg·L-1. In summary, 550 mg·L-1 nano-potassium molybdate spray enhanced carbon assimilation efficiency of rapeseed, while N assimilation efficiency was also significantly increased. The promotion of photosynthesis in rapeseed by nano-potassium molybdate was mainly related to nonstomatal factors: increased photosynthetic pigment contents and enhanced activities of key enzymes for photosynthesis. It could promote the conversion of inorganic to organic N in rape leaves by enhancing the activities of key enzymes of N metabolism. [ABSTRACT FROM AUTHOR]

Re-Os isotope method is a powerful tool for dating ore deposits, but digesting samples with the Carius tube is complicated and dangerous.A simple and quick method to determine the age of molybdenite Re-Os and Re content has been established.5-15 mg of molybdenite samples were digested with 3 mL HNO3 in a 10 mL colorimetric cylinder.Molybdic acid in solution was removed by a centrifuge, the supernatant of the solution was then diluted to an appropriate volume.M187/M185 ratio of the resulting solution was determined directly by Inductively Coupled Plasma-Mass Spectrometry(ICP-MS).According to the principle of radioactive decay, it can be inferred that the mass ratio is positively correlated with the age.The Re-Os age of the sample can be calculated by comparing with the M187/M185 ratio of the molybdenite standard material(JDC and HLP).The Re content in the sample can be calculated on the basis of 185Re counting using the relative method.In order to test the reliability of this method, a series of molybdenite samples, whose ages vary from 13.26 Ma to 2130 Ma, were analyzed.The resulting ages were generally identical to the reference ages within 0.36%-7.42% deviations.The samples with older ages yield better results because the 187Os is more radiogenic.This method, without spike addition, can avoid the trouble of sealing and opening the Carius tube and the process of separating and purifying Re and Os, which significantly improves the experimental efficiency.This simple and quick method is highly suitable for the preliminary analysis of molybdenite Re-Os ageing.

Higher analytical precision and lower detection limit are required in geological dating and tracing, due to the wide application of Os. In this study, high-precision determination of pg-ng Os by Negative Ion Thermal Ionization Mass Spectrometry (NTIMS) was established by reagent purification, vessel cleaning and chemical preparation to ensure the ultra-low blank and obtain sensitive and stable signals. Isobaric oxygen interferences are corrected by stepwise spectrum stripping, and mass discrimination effect is corrected by internal standard iteration. The total procedural blank of Os is 0.41 pg, the signal of 1 pg 190Os is about 85000 cps, and the mass fractionation factor is less than 0.1%. Pg level of Os is measured by ion counter dynamic jumping scan mode and the measurement precision of 187Os/188Os is less than 0.2%. ng level of Os using Faraday cup static mode yielded the measurement precision of 187Os/188Os less than 0.005%. The measured value, 187Os/188Os=0.3361±7 (2RSD, n=9), for national reference material JCBY is identical with the certified value within uncertainty. The analysis precision meets the advanced international laboratory level. This method has the merits of low blank, high sensitivity and high accuracy, and can provide high-precision Os isotope data of geological samples.

To explore the effects of storage temperature and thermal processing on biogenic amines (BAs) contents in meat during storage, contents of BAs in meat were determined by capillary electrophoresis (CE) indirect ultraviolet (UV). The meats were fresh and cooked chicken, beef and pork that were stored at 4 °C (refrigerated condition) for 6 d and 25 °C (room temperature condition) for 24 h, respectively. The results show that spermine (Spm) and spermidine (Spd) contents decrease during storage. Putrescine (Put), histamine (HA), cadaverine (Cad) and tyramine (TA) contents in meat increase rapidly with increasing storage time at 25 °C, while the contents of the four BAs increase slowly with increasing storage time at 4 °C. Under both room temperature and refrigerated conditions, the contents of Put, HA, Cad and TA in fresh meat are higher than those in cooked meat. It indicates that refrigeration conditions and thermal processing can effectively inhibit the increase of BAs contents in meat. BAs contents in pork are lower than that in chicken and beef, which suggests that the type of meat also affects the contents of BAs in meat. [ABSTRACT FROM AUTHOR]

In view of nonlinear characteristic of pressure distribution of high viscous materials like coal slurry in slurry pipeline, the paper put forward a kind of modeling method based on BP neural network optimized by quantum genetic algorithm after analysis of relationship of pipeline pressure and main influence factors based on experimental data. The method optimizes weights and thresholds of BP neural network by quantum genetic algorithm, and uses the optimized BP neural network to approximate nonlinear characteristics of the pipeline pressure of coal slurry, then gets mathematical model. The simulation results show that the pressure distribution model of coal slurry pipeline based on optimized BP neural network has good stability, its error is 0.063 2, which can satisfy engineering requirement, and it is better than the model based on BP neural network in optimization time and accuracy.

[Objectives] To investigate the effects of temperature and humidity on the population dynamics of Grapholita molesta, a pest that causes significant losses to pear crops worldwide. [Methods] A monitoring site was set up in a pear orchard in Daxing, Beijing municipality where sex pheromone traps were used to monitor the population dynamics of adult G. molesta over three years (2018-2021). The data obtained were combined with local meteorological data collected over the same period to analyze the relationship between temperature, humidity and population dynamics. [Results] G. molesta began to appear in the pear orchard in mid to late March. Four population peaks occurred each year; in mid to late April, mid-June, mid to late July and early to mid-September. There was a significant relationship between the average and maximum temperature and population density, which can be described by the equation Y= - 5.62 - 0.16X1+0.72X2+0.52X3+0.18X4, where X3 is the highest temperature, X1 is the average temperature, X2 is the lowest temperature and X4 is the average relative humidity. The relative importance of these factors was: X3> X1> X2> X4. [Conclusion] There is a significant relationship between the occurrence of G. molesta in pear orchards in Daxing, Beijing municipality, and local temperature and humidity data. These results lay a foundation for developing a model to predict the occurrence of G. molesta. [ABSTRACT FROM AUTHOR]