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[Objective] As the most active component in forest soil, dissolved organic matter (DOM) can not only be directly utilized by microorganisms, but also be the main carrier for the migration of C, N, P and other elements in the ecosystem. The migration process is influenced by the hydraulic interactions and dissolving processes driven by throughfall. [Methods] Using soil column microcosm in situ culture to analyze the effects of forest throughfall on the dynamics of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and dissolved organic phosphorus (DOP) across varying layers of sandy red soil during the rainy season. The study focused on a subtropical evergreen broad-leaved forest with rainfall as a control. [Results] (1) During the rainfall season, the DOM input of throughfall into soil increased significantly compared with rainfall(p

In this article, we consider the following quasilinear Schrödinger system: −εΔu+u+k2ε[Δ∣u∣2]u=2αα+β∣u∣α−2u∣v∣β,x∈RN,−εΔv+v+k2ε[Δ∣v∣2]v=2βα+β∣u∣α∣v∣β−2v,x∈RN,\left\{\begin{array}{ll}-\varepsilon \Delta u+u+\frac{k}{2}\varepsilon \left[\Delta \hspace{-0.25em}{| u| }^{2}]u=\frac{2\alpha }{\alpha +\beta }{| u| }^{\alpha -2}u{| v| }^{\beta },& x\in {{\mathbb{R}}}^{N},\\ -\varepsilon \Delta v+v+\frac{k}{2}\varepsilon \left[\Delta \hspace{-0.25em}{| v| }^{2}]v=\frac{2\beta }{\alpha +\beta }{| u| }^{\alpha }{| v| }^{\beta -2}v,& x\in {{\mathbb{R}}}^{N},\end{array}\right. where ε>0,k

Carnosine dipeptidase 1 (CNDP1), an enzyme integral to the hydrolysis of dipeptides containing histidine, plays an indispensable role in myriad physiological processes, including hydrolysis of proteins, maturation of specific biochemical functionalities within proteins, tissue regeneration, and regulation of cell cycle. However, the implications of CNDP1 in oncogenesis and its prognostic value are not yet fully elucidated. Initially, we procured the GSE40367 dataset from the Gene Expression Omnibus and established a protein–protein interaction network. Thereafter, we conducted functional and pathway enrichment analyses utilizing GO, KEGG, and GSEA. Moreover, we undertook an association analysis concerning the expression of CNDP1 with immune infiltration, along with survival analysis across various cancers and specifically in hepatocellular carcinoma (HCC). Our study uncovered a total of 2,248 differentially expressed genes, with a down-regulation of CNDP1 in HCC and other cancers. Our explorations into the relationship between CNDP1 and immune infiltration disclosed a negative correlation between CNDP1 expression and the presence of immune cells in HCC. Survival analyses revealed that diminished expression of CNDP1 correlates with an adverse prognosis in HCC and several other types of cancer. These observations intimate that CNDP1 holds promise as a novel prognostic biomarker for both pan-cancer and HCC.

This work extensively investigated the preparation and dispersion of concentrated aqueous suspensions of H₃PO₄-treated nano-sized Y₂O₃ powder particles. For comparison purposes, the untreated Y₂O₃ powder was also studied. Compared to the untreated Y₂O₃ powder, the treated powder exhibited a narrower particle size distribution and enhanced homogeneity in particle dispersion. In the case of the untreated powder suspension, there was a rapid increase in the pH from 9.34 to 10.4 in a short dispersion time, whereas no variation in the pH was observed for the treated Y₂O₃ suspension during the hydrolysis tests. This was because the phosphate-based protection layer on the surfaces of the particles inhibited the hydrolysis of Y₂O₃ powders, thus enabling the formation of colloidally stable suspensions. TAC was employed as the dispersant in preparing both the treated and untreated Y₂O₃ suspensions. The treated Y₂O₃ suspension exhibited lower viscosity and maintained long-lasting stability for 6 h compared to the untreated one. It was determined that the use of H₃PO₄ at a dosage of 1 wt% allowed one to obtain suspensions with the lowest sedimentation volume and viscosity. A series of treated Y₂O₃ suspensions with solid loadings ranging from 20 vol% to 40 vol% were obtained, which were centrifugal slip cast into cylindrical shapes. The resulting cast green bodies from the 35 vol% treated Y₂O₃ suspensions exhibited a uniform and high packing density of 49.24%.

Objective: To determine the inhibitory effects of pachymic acid on lung adenocarcinoma (LUAD) cells and elucidate its underlying mechanism. Methods: CCK-8, wound healing, Transwell, Western blot, tube formation, and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation, metastasis, angiogenesis as well as autophagy. Subsequently, molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B (PTP1B). Moreover, PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid. Results: Pachymic acid suppressed LUAD cell viability, metastasis as well as angiogenesis while inducing cell autophagy. It also targeted PTP1B and lowered PTP1B expression. However, PTP1B overexpression reversed the effects of pachymic acid on metastasis, angiogenesis, and autophagy as well as the expression of Wnt3a and β-catenin in LUAD cells. Conclusions: Pachymic acid inhibits metastasis and angiogenesis, and promotes autophagy in LUAD cells by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B.

Objective To investigate the endoscopic characteristics of different grades of melanosis coli （MC） complicated with polyps. Methods Clinical and endoscopic data of 597 patients diagnosed with MC who underwent colonoscopy were retrospectively analyzed. The correlation of different grades of MC with age， gender and intestinal diseases was analyzed. The gender， age， polyp size and pathological type of polyps in patients with different grades of MC were analyzed statistically. Results Polyps were more commonly detected in gradeⅠMC than in gradeⅡand gradeⅢMC. The size of polyps significantly differed among different grades of MC. The detection rate of < 0.5 cm polyps in gradeⅢMC was 37.50%， significantly lower than 67.11% in gradeⅠand 60.18% in gradeⅡMC. The detection rate of 0.6-1.0 cm polyps in gradeⅢMC was 57.50%， significantly higher than 23.49% in grade Ⅰand 25.66% in gradeⅡMC. The detection rates of hyperplastic polyps and tubular adenoma significantly differed among different grades of MC complicated with polyp （all P < 0.05）. No statistical significance was observed in the distribution of inflammatory polyp， retention polyp， serrated adenoma and tubular-serrated adenoma among different grades of MC complicated with polyp （all P > 0.05）. Conclusions Polyps are more commonly detected in gradeⅠMC. Polyps of 0.6-1.0 cm in size are more likely to be detected in grade ⅢMC. Hyperplastic polyps are more commonly detected in gradeⅠMC， whereas tubular adenoma in gradeⅡandⅢMC.

Atopic dermatitis (AD) is a relapsing inflammatory skin condition that has become a global health issue with complex etiology and mounting prevalence. The association of AD with skin and gut microbiota has been revealed by virtue of the continuous development of sequencing technology and genomics analysis. Also, the gut–brain–skin axis and its mutual crosstalk mechanisms have been gradually verified. Accordingly, the microbiota–skin–gut axis also plays an important role in allergic skin inflammation. Herein, we reviewed the relationship between the microbiota–skin–gut axis and AD, explored the underlying signaling molecules and potential pathways, and focused on the potential mechanisms of probiotics, antimicrobial peptides (AMPs), coagulase-negative staphylococci transplantation, fecal microbiota transplantation, AMPs, and addition of essential fatty acids in alleviating AD, with the aim to provide a new perspective for targeting microbiota in the treatment of allergic skin inflammation.

Electrochemical reaction is a continuous dynamic process, accompanied by electron transfer and generation of short-lived intermediates. The mechanism investigation of electrochemical interfaces is pivotal for the progression of energy storage, electro-organic synthesis, electrocatalysis, and electroanalysis. The valuable insights for optimizing performance, improving efficiency, and developing novel methodologies can be attained by elucidating the complicated pathways involved in the electrochemical processes. Thus, how to monitor transient intermediates formed at the solid-liquid interface becomes the critical point in unraveling these intricate processes. To this end, a series of in-situ analytical methods such as in-situ electron paramagnetic resonance spectroscopy (in-situ EPR), in-situ Raman spectroscopy, in-situ infrared spectroscopy (in-situ IR) and in-situ electrochemical mass spectrometry (in-situ EC-MS) have been exploited to probe the chemical transformations at the electrode/electrolyte interface. Among them, due to the superior specificity for interpreting molecular information, EC-MS has progressively gained extensive attention as a powerful and reliable tool for capturing intermediates and revealing the mechanisms in electrochemical reactions. In this review, the research progresses in the recent advancements in the detection of transient reaction intermediates through electrochemical mass spectrometry were presented. The discussion centered on elucidating the principle and configuration of the devices employed in EC-MS, with a specific focus on electrospray ionization mass spectrometry (ESI-MS), atmospheric pressure ionization mass spectrometry (AIMS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). In addition, the review delved into the wide-ranging applications of EC-MS in monitoring electrochemical processes in electro-organic synthesis, electrocatalysis, lithium-ion batteries, electrochemiluminescence, and bioelectrochemical reactions. Despite the remarkable progress has made, the challenges in the field of EC-MS are prospected. There is still an urgent need for further improvement of the experimental apparatus to enhance the sampling efficiency and time resolution to capture short-lived and low-concentration reaction intermediates. In the future, we anticipate that EC-MS will be combined with other in situ analytical techniques, such as in situ infrared or Raman spectroscopy, enabling multi-dimensional characterization and monitoring of electrochemical reaction intermediates.

With the continuous research on the basic theory and application technology of photocatalysis, certain progress has been made in the understanding of the preparation, performance mechanism and application aspects of new photocatalysts driven by visible light. Graphitic phase carbon nitride(g-C3N4), as a chemically stable non-metallic material, has attracted much attention from domestic and foreign scholars because of its environmental friendliness and high plasticity. In recent years, the exploration and application of g-C3N4 based materials in the field of photocatalysis have been developed rapidly. Among them, the strategy of doping non-metallic elements was particularly prominent, which has become a research hotspot in materials science and environmental chemistry and other disciplines.In order to sort out and summarize the relevant researches in a timely manner, the current research status of non-metal-doped modified g-C3N4-based photocatalytic materials in recent years was summarized and reviewd in this paper, the preparation methods of non-metal-doped g-C3N4 and its applications in photocatalysis was systematically discussed, and an outlook was presentd on its future development direction, such as the applicontion of photoatalysis, photothermal catalysis, and piezoelectric photocatalysis, which will the further explored.

In order to improve the core power density of liquid metal reactors, plate-type fuel assemblies are typically used, which have obvious advantages in heat transfer capacity. For the low Prandtl number fluid, the RANS turbulence model-based CFD method needs to be modified by inserting the turbulent Prandtl number model. This paper investigated the turbulent Prandtl number model for the turbulent heat transfer of liquid metal flow in a narrow rectangular channel. First, the existing turbulent Prandtl number models were summarized and classified as the local turbulence Prandtl number model and the global turbulence Prandtl number model. They were evaluated based on the experimental data. The results showed that the prediction results of each model are not ideal. Then, a typical numerical example was used to analyze the temperature field and flow field in the narrow gap of a narrow rectangular channel. It was shown that the entire flow region only includes the near-wall region and the transition region, and the transition region accounts for the main proportion. A semi-empirical local turbulence Prandtl number model was obtained by solving the turbulent transport equation, and the unknown coefficients were determined iteratively with the experimental data. The error was controlled within ±20%. Finally, the applicability of the newly proposed turbulent Prandtl number model was explored, and the results showed that it has good applicability for the different runner sizes and different liquid metal types. This study can provide a reference for the numerical simulation of turbulent heat transfer of metal liquid in the narrow rectangular channel.

Objective To investigate the diagnostic value of fecal calprotein (FCP) combined with C-reactive protein (CRP) in severe Clostridium difficile infection (CDI) in order to provide a reference for improving the diagnostic strategy of severe CDI. Methods A case-control trial was conducted on 73 patients diagnosed with CDI and treated in our hospital from January 2020 to December 2022. They were divided into mild-moderate CDI group and severe CDI group. Demographic information and severity-related factors were selected as variables, univariate and multivariate logistic regression analyses were employed to analyze the risk factors for severe CDI, and receiver operating characteristic (ROC) curve was plotted to determine diagnostic values of CRP and FCP. Results Comparison of clinical data between the 2 groups showed that more patients having fever (P=0.028), higher serum CRP (P < 0.001) and FCP levels (P < 0.001) were observed in the severe CDI group. Multifactorial analysis indicated that both serum CRP level (P=0.005, OR=1.028, 95%CI: 1.008-1.049) and FCP level (P < 0.001, OR=1.023, 95%CI: 1.010-1.036) were independent risk factors for severe CDI. ROC curve analysis revealed that both serum CRP level (AUC: 0.753, 95%CI: 0.626-0.880) and FCP level (AUC: 0.794, 95%CI: 0.671-0.917) had a moderate predictive value for severe CDI, and their combination had a high predictive value for severe CDI (AUC: 0.923, 95%CI: 0.865-0.982). Conclusion FCP is an independent risk factor for severe CDI, and FCP combined with CRP shows more accurate diagnosis for severity of CDI, which provides a basis for choosing an appropriate antibiotic regimen.

Objective·To explore the role played by the differentially expressed SRY-box transcription factor 9 (SOX9) gene in diffuse large B cell lymphoma (DLBCL), particularly in the regulation of metabolic reprogramming in the germinal center B-cell (GCB) like subtype.Methods·The clinical information and gene expression profile data of 481 DLBCL patients retrieved from the NCICCR-DLBCL database were included. Data analysis and visualisation were performed by using R language version 4.1.3. The classification was performed by using a cell of origin subtype (COO) classification algorithm based on RNA-seq sequencing of expression. ABC/GCB features were used to annotate gene sets, and the classification was verified by gene set enrichment analysis. The ABC and GCB subgroup was dichotomised based on the mean expression of SOX9. Differential analysis was performed by using the DEseq2 package. The relationship between SOX9 and ABC-DLBCL metabolism was analysed by using KEGG (Kyoto Encyclopedia of Genes and Genomes) with the Hallmark annotation set. The survival curves were plotted by using the Kaplan-Meier method. The pan-cancer analysis was performed by using GEPIA2. The microenvironmental scoring analysis was performed by the ESTIMATE package.Results·Of the 481 DLBCL patient samples, all the patients had RNA-seq expression data, 421 had clinical staging, 335 had international prognostic index (IPI) scores and 234 had survival data. The classification yielded 232 (48.2%) ABC subtypes, 173 (36.0%) GCB subtypes and 76 (15.8%) unclassified, consistent with the proportions declared in the database, and the enrichment analysis was verified to be consistent with the ABC/GCB expression profile. Compared to the high SOX9 expression group, the overall survival was shorter in the low SOX9 expression group and the prognostic score was worse. The pan-cancer analysis showed that this phenomenon was also seen in other tumor types. The differential analysis showed that there were 156 upregulated genes and 1 826 downregulated genes in the GCB subtype in the low SOX9 expression group, compared to the high SOX9 expression group. For metabolic processes, down-regulated genes were enriched in glycolysis.Conclusion·In the ABC subtype of DLBCL, the SOX9 gene affects the biological features of ABC-DLBCL by regulating metabolic reprogramming, and low expression of SOX9 in DLBCL, possibly caused by high methylation, predicts decreased glycolysis in tumors. The proportion of tumor stromal cells decreases, showing a worse prognosis.

In this study, the fermentation supernatant, cells and disrupted cell supernatant of five strains of lactic acid bacteria (LAB) were screened for tyrosinase inhibitory activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The results showed that the tyrosinase inhibitory activity of the fermentation supernatant was much higher than that of the cells and the disrupted cell supernatant. The percentage inhibition of tyrosinase activity by the fermentation supernatant of strain MNJ-9 was 68.9% compared to only 50.9% with the cells and 34.8% with the disrupted cell supernatant. The fermentation supernatant of strain MNJ-9 scavenged 93.1% of DPPH radical. Meanwhile, MNJ-9 was identified by 16S rDNA gene sequencing. The major components of the fermentation supernatant of MNJ-9 were investigated using untargeted metabolomics based on liquid chromatography-mass spectrometry (LC-MS). The tyrosinase inhibitory activity and DPPH radical scavenging capacity of 10 of the major components were measured. The results showed that 5-aminovaleric acid had the highest tyrosinase inhibitory activity and DPPH radical scavenging capacity. The cytotoxicity of 5-aminovaleric acid on mouse melanoma cells (B16F10), and its impact on the melanin content and tyrosinase activity of B16F10 cells were determined to evaluate its whitening ability. The results showed that the cell survival rate was equal to or over 80% after culture for 72 h with 70 μg/mL of 5-aminovaleric acid, indicating no apparent cytotoxicity. At 5-aminovaleric acid concentrations of 10–70 μg/mL, the intracellular melanin content and tyrosinase activity were 85.4%–45.2% and 76.53%–40.5%, respectively. This indicates that 5-aminovaleric acid has some whitening ability.

【Objective】 Biochar amendment has been widely used to improve soil quality and remediate soil contamination. The objective of this paper is to elucidate the impact of its combination with brackish water irrigation on water flow and salt transport in saline-alkaline soils in the Yellow River Delta. 【Method】 The experiment was conducted using soil columns. Soil taken from the delta was amended with biochar of wheat or maize straw respectively. There were 10 treatments by applying 10 t/hm2 (X1) and 20 t/hm2 (X2) of wheat biochar (X1), or 10 t/hm2 (Y1) and 20 t/hm2 (Y2) of maize biochar. The control was irrigation with deionized water (CK). The concentration of the brackish water was 3 g/L. In each treatment, we measured the movement of water, salt and soil pH. 【Result】 Amending soil with biochar combined with brackish water irrigation improved soil infiltration capacity and water retention in the soil. The wheat straw biochar worked better in improving infiltration than the maize straw biochar. Biochar amendment combined with brackish water irrigation also facilitated salt leaching, reducing salt content in the soil by 7.3% to 10.44%, compared to the CK. Wheat straw biochar worked better in de-salinizing the soil than maize straw biochar, especially the X1 whose desalination rate was 53.74%. The addition of biochar combined with brackish water irrigation increased soil pH, albeit not significantly, especially the maize straw biochar in X2 which affects soil pH most. 【Conclusion】 Amending the soil with 10 t/hm2 of wheat straw biochar combined with brackish water irrigation was effective to improve the quality of the saline soils in the Yellow River Delta region. Results of this study provide guidance to sustainably utilize brackish water and biochar to improve productivity of the saline-alkaline soils in Yellow River delta and areas with similar conditions.

How to simultaneously obtain the depth, edge, and other light information of the scene to accurately perceive the physical world is an important issue for imaging systems. However, such tasks usually require bulky optical components and active illumination methods. Here, we design and experimentally validate a single geometric metasurface that can achieve depth measurement or edge detection under incoherent or coherent light respectively. Double helix point source function is utilized, and three verification experiments are carried out, including double-helix beam calibration, 2D object and 3D object detection, respectively. Additionally, two-dimensional edge detection can also be achieved. This compact imaging system can enable new applications in various fields, from machine vision to microscopy.

The selection of college grants is affected by many factors, but some of the influencing factors cannot be quantitatively judged at present. In order to be more fair and reasonable to the students in need of financial assistance for the review and evaluation, this paper introduces the fuzzy comprehensive evaluation method into the process to establish a fuzzy hierarchical analysis based on the college national scholarship evaluation model, the article finally through a specific example of the application of this paper based on the fuzzy comprehensive evaluation of the optimization model of the bursary system. The affiliation degree of the fuzzy comprehensive evaluation-based scholarship system constructed in this paper is (0.536,0.323,0.130,0.014), and the article concludes that Zhang’s moral education status is very good, and he is qualified to receive the scholarship.

To be able to better develop local folk music and traditional culture, this paper proposes the optimization of local folk music teaching and transmission paths. Analyze the musical styles taught in colleges and universities, learn that ethnic music with a strong national culture is not asked for, build a more comprehensive and three-dimensional system of musical knowledge, master the cultural connotations of ethnic music, strengthen the understanding of their own group culture, and lay the foundation for survival and development in a multicultural society. According to single or multiple continuous or discrete analysis of folk music teaching transmission paths, the state variables of the path optimization process are set to ensure that the growth rate coefficient of the teaching transmission path is positive and the growth rate of teaching is positive. Combining the amount of teaching demand for local ethnic music, the inflection point of the path curve is substituted into the transmission path to obtain the path state variable values. Using the fruit fly optimization algorithm to strengthen the Logistic model, the individual flight distance and direction of fruit flies are preset, and the distance value between the fruit fly position and the origin is calculated to locate toward the target position with visual advantage, and finally the music teaching transmission path optimization is realized. The analysis results show that the logistic model combined with the FOA algorithm has a significantly higher test rate both for subsamples and full samples, and the value of 0.45 is closer to the true value of 0.46, which has a strong applicability and a good path optimization effect.

Neuromyelitis optica spectrum disorders(NMOSD), an inflammatory demyelinating disease of central nervous system, is characterized by optic neuritis, longitudinally extensive transverse myelitis, and neuropathic pain. Given the lack of mature animal models, the mechanism of neuropathic pain in NMOSD is still unclear, although some studies have reported neuropathic pain in NMOSD models. It is therefore necessary to build a reliable and feasible animal model of NMOSD related neuropathic pain, in order to provide scientific support for the mechanism and the mining of therapeutic targets. This article reviews the research progress of the establishment of NMOSD-related neuropathic pain animal models and their applications, and provides a reference for the establishment of ideal NMOSD neuropathic pain animal models.

Environmental pollution is one of the most significant public concerns in modern society, which is harmful to ecology and human health directly or indirectly. Among different types of environmental pollutants, environmental endocrine disruptors, drugs and personal care products are more serious in water and soil. In order to deal with the residues of environmental pollutants and avoid their long-term potential harm to human health, there is an urgent need to develop a rapid and accurate method for analyzing and monitoring environmental pollutants. As one of ambient ionization mass spectrometry, direct analysis in real time mass spectrometry (DART-MS) has the advantage of ease of use, rapid analysis and minimum sample preparation. It can realize fast sampling under ambient conditions and serve a promising technique for environmental pollutant screening. In this review, the principle of DART-MS and its characteristics were introduced firstly, and then the application of DART-MS in the detection of pesticide residues, veterinary drugs and abused drugs, and environmental pollutants were briefly summarized. Finally, methodology and application of DART-MS in the screening of environmental pollutants were prospected.

Two-component systems typically consist of a paired histidine kinase and response regulator and couple environmental changes to adaptive responses. The response regulator VbrR from Vibrio parahaemolyticus, a member of the OmpR/PhoB family, regulates virulence and antibiotic resistance genes. The activation mechanism of VbrR remains unclear. Here, we report the crystal structures of full-length VbrR in complex with DNA in the active conformation and the N-terminal receiver domain (RD) and the C-terminal DNA-binding domain (DBD) in both active and inactive conformations. Structural and biochemical analyses suggest that unphosphorylated VbrR adopts mainly as inactive dimers through the DBD at the autoinhibitory state. The RD undergoes a monomer-to-dimer transition upon phosphorylation, which further induces the transition of DBD from an autoinhibitory dimer to an active dimer and enables its binding with target DNA. Our study suggests a new model for phosphorylation-induced activation of response regulators and sheds light on the pathogenesis of V. parahaemolyticus.

In order to solve the system of compatible nonlinear equations, the author proposes a hybrid computational intelligence method of Newton's method and genetic algorithm. First, the Quasi-Newton Methods (QN) method is given. Aiming at the local convergence of the algorithm, it is easy to cause the solution to fail. By embedding the QN operator in the Genetic Algorithm (GA) and defining the appropriate fitness, thus, a hybrid computational intelligence algorithm of CNLE is obtained that combines the advantages of GA and QN method, which has both faster convergence and higher probability of solving. Experimental results show that: The value of the selection probability pn of the QN operator also directly affects the solution efficiency. Generally speaking, for strong nonlinear CNLE composed of multimodal functions, pn can be larger; For weakly nonlinear CNLE composed of functions with fewer extreme points and stronger monotonicity, pn can be smaller. It is demonstrated that the computational results show that this method significantly outperforms the GA and QN methods.

ObjectiveTo analyze the chemical structure of the interfering substance that affects the result of methamphetamine analysis in wastewater.MethodsA combination of GC-MS and liquid chromatography-quadrupole time-of-flight mass spectrometry （LC-QTOF-MS） was used to analyze the mass spectrum characteristics of the interfering substance that affects the result of methamphetamine analysis and to infer its possible structure. Liquid chromatography-triple quadrupole-mass spectrometry （LC-TQ-MS） was used to confirm the control material.ResultsUsing LC-QTOF-MS in positive electrospray ionization （ESI+） mode, the mass-to-charge ratio （m/z） of quasi-molecular ion in the MS1 mass spectrometry of interfering substance was identical to that of methamphetamine, indicating that the interfering substance was probably an isomer of methamphetamine. The MS2 mass spectra obtained at three collision energies of 15 V, 30 V and 45 V were highly similar to methamphetamine, suggesting that the interfering substance contained methylamino and benzyl groups. Further analysis using GC-MS in electron impact （EI） ionization mode showed that the base peak in the mass spectrum of the interfering substance was at m/z 44. The interfering substance was confirmed to be N-methyl-2-phenylpropan-1-amine by compared with the standard reference.ConclusionThe chemical structure of N-methyl-2-phenylpropan-1-amine is highly similar to methamphetamine, which is easy to cause interference for the detection of trace amounts of methamphetamine in wastewater using LC-TQ-MS. Therefore, in the actual analysis, the chromatographic retention time can be used to distinguish between N-methyl-2-phenylpropan-1-amine and methamphetamine.

In order to explore the influence of the variation of hemispherical bevel gear parameters on the dynamic characteristics of the system, a dynamic model of the hemispherical bevel gear pair is established based on the lumped mass method. Based on high-quality hexahedral mesh model, the dynamic transmission performance of hemispherical bevel gears is analyzed by rigid-flexible coupling flexible body dynamics simulation. The influence of parameters such as the size of hemispherical bevel gears and the shaft angle on the motion state of the system is analyzed. The simulation results show that the transmission accuracy, stability and strength of the system change regularly and are negatively correlated with each other under different parameters. The comprehensive performance of hemispherical bevel gears is the best when the diameter of indexing circle is 65 mm and the angle of intersecting shaft is 120°. The flexible multi-body dynamics simulation analysis provides an important reference for the model design, processing and manufacturing of hemispherical bevel gears.

Infertility is a major health concern worldwide. This retrospective study aimed to assess the predictive value of the morphokinetic parameters of temporary-arrest embryos for the pregnancy outcomes of women undergoing frozen embryo transfer (FET) cycles. In this study, we evaluated 244 FET cycles with 431 day-4 temporary-arrest embryos. They were categorized into two groups (pregnancy and non-pregnancy) according to the pregnancy outcomes of the women after embryo transfer on day 5, and their fundamental characteristics were compared. The morphokinetic parameters from the time-lapse monitoring system were assessed according to different pregnancy outcomes. The mean number of embryo blastomeres thawed on day 3 in the pregnancy group was 7.47, which was significantly higher than the number in the non-pregnancy group (p < 0.01). Besides, embryos in the non-pregnancy group contained more embryo fragments and lower grades than those in the pregnancy group (p < 0.001). Furthermore, morphokinetic parameters: tPNa, t2, t5, and t5_tPNf showed a statistical difference between the pregnancy and non-pregnancy groups (p < 0.05). Receiver-operating characteristic analysis revealed that the time from pronuclear fading to the 5-cell stage (t5_PNF) predicted the clinical prognosis outcomes (area under the curve = 0.64; 95% confidence interval [CI], 0.58–0.70; p < 0.001). The morphokinetic parameter t5_PNF could be regarded as a potential implantation predictor in our study.

Renewable energy DC hydrogen production has become a new development trend. Due to the interaction between the weak damping of DC network and the negative impedance characteristics of power supply of hydrogen production, the actual available power of renewable and hydrogen energy DC interconnection system will be lower than its rated setting value. To solve this problem, this paper proposes an intelligent damping control to realize the rated power operation of hydrogen generation power source and significantly improve the hydrogen generation performance. In this paper, the nonlinear model under typical control strategies is established in order to adapt to different degrees of disturbance, and the damping controller is designed based on state feedback, including feedback control law and damping generation formula. On this basis, an intelligent method of damping control is proposed to support rapid decision-making. Finally, the intelligent damping control method is verified by simulation analysis. It realizes rated power of power supply of hydrogen production by generating only a small amount of damping power and superimposing it on the hydrogen production power.

Objective To observe the effect of dopamine pretreatment of the root canal on improving the bonding performance of AH-plus sealer. Methods A total of 32 freshly isolated permanent teeth with a single canal were collected, with no caries, no fracture of roots, and a root canal curvature0.05). Root canals treated with 2 mg/mL dopamine had the highest bonding strength in all groups (P

Objective To evaluate prospectively the side effects and tolerance of docetaxel with concurrent late-course hyperfractionated radiotherapy after breast-conserving surgery for stage T1-T2 breast cancer, and to assess the value of this treatment in shortening the treatment time and reducing the economic burden among patients. Methods A total of 20 patients with T1-T2 breast cancer were recruited after they underwent breast-conserving surgery. The acute radiation response classification, treatment completion rate, disease-free survival, hospital stays, and treatment costs were observed. Radiotherapy for all patients was started before the last single-agent docetaxel chemotherapy. Results The completion rate of treatment and the good rate of cosmetic effect reached 100%. The main adverse reactions were hematological toxicity (leukopenia) and skin reactions, which were tolerated. The median follow-up time was 30.1 months, and the follow-up rate was 100%. The average total treatment time of this hyperfractionated radiotherapy with concurrent docetaxel was four weeks, and the total hospitalization cost savings was approximately 10, 000 yuan. The 21-month disease-free survival rate was 100%. Conclusion Stage T1-T2 breast cancer can tolerate hyperfractionated radiotherapy with concurrent chemotherapy after a breast-conserving operation. The procedure results in good local control and satisfactory cosmetic effects, with high health and economic value.

Quantum computing has the capability of parallel computing and is superior to classical computing in solving some specific problems. Once a large-scale quantum computer is developed, the security of classical cryptographic algorithms and protocols, which is based on the assumption of computational complexity, will be severely challenged. Quantum cryptography is a new cryptosystem; its security is based on the principles of quantum mechanics, and can resist the attack of quantum computing. This paper focuses on the nearly 40 years development of quantum cryptographic protocols, including quantum key distribution (QKD), quantum secure direct communication, quantum secret sharing, quantum identity authentication, two-party secure computation, and quantum private query, and summarizes the problems in the process of development. The analysis shows that the quantum cryptographic protocols are in an unbalanced state: QKD is far ahead of other protocols and other protocols are difficult to achieve breakthroughs. In the future, practical quantum protocols for digital signature and two-party secure computation are core issues that needs to be addressed urgently. Therefore, research on quantum and post-quantum cryptography should be conducted synchronously, cross-over study and talent cultivation for the quantum science and cryptography disciplines should be strengthened, and the examination and evaluation mechanism of relevant basic research needs to be optimized.

Theaflavins are a class of natural products extracted from black tea or green tea, with significant anti-tumor effects on gastric cancer, liver cancer, breast cancer and other tumors. Theaflavins were once considered as the new products for anticancer therapy. However, the anti-tumor mechanism of theaflavins involves a variety of biological processes, and the regulation is complex. Therefore, this article summarizes the role of theaflavins in promoting tumor cell apoptosis, inducing tumor cell mitotic arrest and regulating tumor immunity, and reviews the inhibition of tumorigenesis and growth through MAPK, PI3K/AKT, Hedgehog, NF-κB, JAK/STAT and Wnt/β-Catenin signal pathways, in order to provide new ideas for cancer treatment and anti-cancer drug development.

Objective: In order to explore the effect of an external electrostatic field on the growth of ice crystals during food freezing. Methods: Based on the classic Kobayashi model of phase field method, the free energy density of electric field was introduced into the phase field model. Used the five-point difference scheme in the finite difference method to discretize the partial differential equation, the simulation and visualization of ice crystal growth were realized by programming. Results: The results showed that the simulation results were consistent with other simulation results and experimental results, and the ice crystal morphology had a typical sixfold symmetry; With the increase of electric field intensity, the growth rate of main branches and nucleation growth of ice crystals were inhibited. Conclusion: In the process of quick-frozen food preservation, adding a certain electric field strength will reduce the formation of ice crystals, and retain the quality and flavor of food as much as possible.

Housing has always been a hot issue in various disciplines. Only when people live in peace can they be happy to work and achieve sustainable economic and social development. In recent years, the construction of a large number of subsidized housing communities has provided material protection for low- and middle-income groups, achieving initial results. However, problems in the construction of supporting facilities and site selection have become increasingly prominent. Therefore, it is important to study the spatial characteristics of the daily activities of the residents of affordable housing to better understand their daily needs and promote the development of affordable housing. Taking a typical community of low-cost housing in Fuzhou City as an example, this study used data from a questionnaire survey and 48 h activity log survey in December 2020, and combined in-depth interview materials from typical samples as the database for this study. Based on the theory of time geography, this study investigated the temporal and spatial behavior characteristics of low-rent housing residents from a microscopic perspective. With the help of GIS visualization techniques, such as 95% standard confidence ellipse, point density analysis, and overlay analysis methods, this study adopted a hybrid analysis method combining qualitative and quantitative analysis to study the spatial characteristics of three types of activities of working, shopping, and leisure of low-rent housing residents on one weekday and one rest day and their use of nearby space from the perspective of micro-individuals, and analyzed their influencing factors using multiple linear regression. The results showed that 1) there is a big difference between the activity space of residents in the case community on weekdays and rest days. The activity space of the sample was more fixed on weekdays, and the working and shopping activities were more dependent on the Juyuanzhou area. On the rest days, the average area of the residents' activity space was four times larger than that on weekdays. Residents needed to use a larger area to meet their shopping and leisure needs, and there were greater internal differences among the samples. 2) Residents had relatively small internal differences in work activities, and their workplaces were mainly distributed in the Juyuanzhou area, with a strong dependence on the Juyuanzhou area. The area of activity space was significantly positively influenced by the residents' income, age and work commute distance. 3) Influenced by residents' travel intentions, there was a big difference between residents' shopping and leisure activities between weekdays and rest days. Workdays relied more on the surroundings of the community, while on the rest days, the internal differences in the resident sample increased. Both shopping and leisure spaces had a significant tendency to expand and decay in distance. Shopping and leisure activities were concentrated within 500 m on weekdays and extended to 5 km on rest days. A comparative analysis with the conclusions of related studies revealed the following significant characteristics of low-rent housing residents in Fuzhou: 1) Short commuting distances to work and dependence on community surroundings. 2) Compared with weekdays, the proportion and space scope of residents' rest days for shopping and leisure activities increased significantly, but the spatial scope of activities was still limited due to the limitation of transportation. Unlike the trend of positioning subsidized housing in first-tier cities, such as Beijing and Shanghai, at the edge of the city, Fuzhou has a large space for inner-city renewal and suburban development, and still has enough space to make the siting of subsidized housing relatively balanced. Finally, in view of the existing problems of the case community, some reference measures are provided for the optimization of low-rent housing from two aspects: planning and construction and community building.

Single pixel imaging as an alternative to traditional imaging methods, has attracted extensive attention in various research fields. Metasurfaces with subwavelength unit cells and compact footprint can be used as a substitute for traditional optical elements. In this work, we propose a single pixel imaging scheme based on metasurface composed of photon sieves, where spatial modulation is realized through shifting. Spatial multiplexing capability is demonstrated by this shifting mode, which can obtain more patterns in limited space and greatly increase the mask capacity. Benefited from the simple structure and easy manufacture of photon sieves, large capacity metasurface can be manufactured. Meanwhile, metasurfaces can simplify the single pixel imaging system, leading to the system miniaturization and integration. In addition, numerical and optical experiments prove that our proposal can operate at the range from the entire visible light to near-infrared light. Such scheme provides a new way for single pixel imaging and would be applied in microscopic imaging, dynamic imaging, hyperspectral imaging, and so on.

Rare disease (RD)is the general term for a class of diseases with very low prevalence.Due to the relatively small number of patients with rare diseases, the diagnosis and treatment, drug research and development, medical safeguard, and scientific research of rare diseases are poorly developed, which highlight the difficulty in diagnosis and treatment, lack of availability of treatment drugs, and lower rate of medical safeguard. In 2018, China's First Edition of Rare Diseases Catalogue was published, which for the first time defined the management scope of rare diseases and promoted research development in field of RD.Since the 13th Five-Year Plan, China has launched a series of policies and measures outlining prevention and treatment of rare diseases, drug research and development, registration, accessing healthcare, and scientific research.In order to further improve the diagnosis, treatment, and management of rare diseases, and better safeguard the health rights and interests of patients with RDs, this paper focuses on the policies and exploration and practice related to rare diseases in China in recent years, and makes suggestions for future policy reviews.

With the rapid development of the world economy, some developing countries only pay attention to the growth rate of GDP, but ignore the importance of sustainable development. The extensive economy, which relies on a lot of energy to drive economic growth, can no longer meet the development requirements of a low-carbon economy. Fundamentally changing this mode of economic growth, optimising the energy structure will become an effective key path. This paper starts with the current situation of the government's development of a low-carbon economy, and analyses the factors affecting it. In order to develop a low-carbon economy, reducing haze pollution and greenhouse gas emissions, energy conservation and emission reduction work of the logistics industry becomes imminent. To analyse the current situation of logistics energy efficiency and structure, qualitative and quantitative research methods are used to measure the impact of these indicators on a low-carbon economy, predict the total energy demand and supply under different scenarios, and formulate the best scenario to optimise the energy structure. Finally, the government put forward the grey prediction management scheme for the development of a low-carbon economy.

As the pace of national modernisation accelerates, the society urgently needs talents with entrepreneurial qualities and innovative spirit. Therefore, colleges and universities need to vigorously cultivate the entrepreneurial quality and innovative spirit of college students. We believe that the quality evaluation index system for implementing innovation and entrepreneurship education should be constructed from the perspectives of university students, colleges and universities and the external environment. The article constructs a structural equation model (SEM) with seven hidden variables and 23 observed variables. By revising the hypothetical model, it is concluded that the total effect of cultivating innovative and entrepreneurial talents is 0.48. Therefore, we believe that the current development of postgraduate innovation and entrepreneurship education is still very unsatisfactory. The entrepreneurial situation of students has not attracted the attention of colleges and universities. The allocation of resources, full-time teachers and the curriculum system need to be further improved.

The article analyzes why colleges and universities should strengthen innovation and entrepreneurship education based on “mass entrepreneurship and innovation”’ First, we conduct a questionnaire survey on the status of college students’ innovation and entrepreneurship attitude and use nonlinear methods to construct an evaluation model of innovation and entrepreneurship capabilities to evaluate students’ innovation and entrepreneurship capabilities quantitatively. Finally, we verify the effectiveness of the combined evaluation model through data on the innovation and entrepreneurship activities of college students. The research results can provide a new idea for appraisal of college students’ innovation and entrepreneurship ability.

This article summarises 15 factors that affect the collaborative innovation of industry, university and research through literature research and establishes the innovation entity and innovation environment subsystem of the collaborative innovation system of colleges and universities based on the theory of synergy. By setting system boundaries and causal relationship analysis, the dynamic model of the collaborative innovation system in colleges and universities is established, and the model's validity is verified. Combining the actual work, the enlightenment of collaborative innovation management in colleges and universities is as follows: Develop collaborative innovation led by scientific and technological talents strategy. Strengthen the policy and system support for collaborative innovation of colleges and universities. Improve the collaborative innovation input mechanism of institutions of higher learning.

How to realize more reasonable noise addition in location differential privacy-preserving is a hot topic issue.However,adding the same amount of noise in different locations will result in the decrease of service availability and privacy preservation.To this end,a differentially private location privacy-preserving scheme with semantic location is examined in this paper,which can systematically solve the contradiction among privacy-preserving,service availability and time overhead.The proposed method firstly constructs the expected distance by employing the framework of geo-indistinguishability,then determines the sensitivity of different locations by using the privacy quality function and requirement function,and finally adds Laplace noise to different types of region at fine granularity according to the location sensitivity.Comprehensive simulation experiments are carried out on two public datasets,which compare the proposed scheme with the existing methods in terms of query success rate based on Bayesian attack,service availability based on expected distance quantization and time overhead.The experimental results demonstrate that the proposed scheme is feasible and effective,and obtains a better trade-offs among privacy preservation,service availability and time consuming.

With the rapid development of packaging industry and the improvement of environmental protection requirements of human society, biodegradable functional packaging film materials have attracted great attention. However, commercial biodegradable functional package film materials have been constrained by its high cost, low mechanical properties and water resistance. The lignin microspheres were firstly prepared by self-assembling and were adhered to the surface of cellulose film via self-depositing, resulting in fabrication of novel cellulose-based UV-blocking film materials. Subsequently, the surface morphology, ultraviolet resistance and mechanical properties of the obtained functional film materials were studied. The surface properties of films were investigated by scanning microscopy (SEM),infrared spectroscopy (FTIR) and confocal laser scanning microscopy.The mechanical properties and UV resistance of cellulose based films were characterized by tensile test and UV transmittance test.It is noteworthy that the lignin microspheres with 1-2 μm in size are uniformly distributed on cellulose films and hydrophobic modification of cellulose-based films facilitated the deposition of lignin. Moreover, the deposited contents of lignin microspheres increase with the increase of the lignin concentration in solution. Due to the introduction of lignin microspheres, the strength of cellulose composites film increases by 22% and the UVB-shielding capacity reaches 94% as compared with the controlled cellulose films.

Supercapacitors have become a new type of energy storage device widely used due to their high efficiency, fast speed and good cycle stability, and electrode material is a key issue restricting their development. The porous niobium nitride fibers were prepared by electrospinning combined with reduction nitride technology using pentachloride as raw material, and Nb4N5||Nb4N5 symmetrical button capacitance was prepared. In order to improve the electrochemical performance of electrode material, NaHCO3 was added into Na2SO4 electrolyte. The results show that the prepared niobium nitride fiber exhibits a tetragonal phase, continuous and porous on the surface. The porous niobium nitride electrode has two mechanisms of electric double layer and pseudocapacitive energy storage. The specific capacitance of the capacitor increases to 187 F·g-1 with the NaHCO3 addition of 15 mmol·dm-3. The buffering effect inhibits the dissolution of niobium nitride, effectively reduces the solution resistance, the solution impedance R1 and the diffusion impedance WR reduce to 1.22 Ω and 1.47 Ω respectively and the ionic conductivity improves. The carrier concentration increases to 6.58×1024 cm3, and the relaxation time of the capacitor is shortened to 0.24 s at the same time.

Objective: In order to improve the quality of cantaloupe production and shorten the drying period. Methods: Use different blanching time (0.5, 1.0, 1.5, 2.0, 2.5 min), impregnation liquid (0.1%, 0.2%, 0.3%, 0.4%, 0.5% citric acid solution) to pretreat cantaloupe slices, and study different hot air temperature (35, 45, 55, 65, 75 ℃), air velocities (0.5, 1.0, 1.5, 2.0, 2.5 m/s), and slice thicknesses (2, 4, 6, 8, 10 mm) on the hot air drying characteristics and moisture diffusivity coefficient of cantaloupe slices, different thin-layer drying mathematical models were fitted. Results: 0.4% citric acid pretreatment yields the best quality dried product, and the temperature and thickness influenced slice drying significantly. There was no constant drying stage in cantaloupe slices drying with the effective moisture diffusivity coefficients of 1.134 8×10-7~4.908 0×10-7 m2/s and activation energy of 28.15 kJ/mol. Conclusion: The optimal hot air drying process of cantaloupe slices drying is as followed: hot air temperature of 55 ℃, air velocities of 2.0 m/s, slice thickness of 6 mm, under the conditions, Page model has the highest R2 value and the lowest root mean square error, which is more suitable for evaluating the moisture removal law of hot-air drying of cantaloupe slices.