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In this study, headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS) and odor activity value (OAV) analysis were used to investigate the changes in aroma components of Baiyaqilan oolong tea before and after roasting. The results showed large differences in the types and contents of aroma components in Baiyaqilan tea before and after roasting. The major aroma components before roasting included geraniol, dehydrolinalool, cis-bergamotene, phenylethanol, phenylacetaldehyde, cis-jasmone and geranyl acetone. The major aroma components after roasting included geraniol, dehydrolinalool, oxopholone, cis-jasmone, geranylacetone, cis-coumarin, phenylethanol, phenylacetaldehyde, safranal, trans-2-decenal, oxoisophorone, cis-bergamotene, cosmene, cis-linalool oxide, and 2-pentylfuran. The changes in aroma of Baiyaqilan tea after roasting were attributed to mechanisms such as volatilisation of low-boiling substances, conversion of α-lonone, thermal decomposition of glycosides, oxidation of alcohols, peroxidative decomposition of lipids, and conversion of terpenes and alcohols, resulting in the production of oxopholone, cis-linalool oxides, and 2-pentylfuran as well as a substantial increase in the contents of safranal, trans-2-decenal and cosmene. In summary, this study revealed that the roasting process produced aroma components, altering the aroma profile of oolong tea, and for the first time it was found that the roasting process could lead to the production of the key aroma components including oxopholone. These results provide a reference for in-depth understanding of the effect of the roasting process on the aroma components of oolong tea.

C31H28N2O2, triclinic, P1‾$P\overline{1}$ (no. 2), a = 9.0809(9) Å, b = 9.2626(9) Å, c = 14.8540(15) Å, α = 93.574(8)°, β = 98.554(8)°, γ = 99.558(8)°, V = 99.558(8) Å3, Z = 2, Rgt(F) = 0.0541, wRref(F2) = 0.1424, T = 293(2) K.

Herpes zoster, known as "snake sore", "waist sore" and "spider sore" in Traditional Chinese Medicine, seriously affects the quality of life and health status of patients. This paper reviews the application progress of Traditional Chinese Medicine and theory of syndrome differentiation in clinical nursing of herpes zoster in recent years, and provides reference for improvement of integrative treatment of herpes zoster. (带状疱疹属中医学“蛇缠疮”“缠腰火丹”“蜘蛛疮”范畴, 严重影响患者的生活质量及健康状态。本研究就以辨证施护理论为导向的护理模式在带状疱疹的应用现状进行综述, 旨在为进一步完善该病的中西医结合疗法提供参考。)

Whether the pilot registration system reform can achieve the expected effect is related to the pace of China’s comprehensive implementation of the registration system reform. This paper selects the data of listed companies on the Science and Technology Innovation Board and the data of listed companies on the Growth Enterprise Market after the pilot registration system. At the same time, the data of listed companies before the GEM registration system reform were selected as a comparative sample. Using the stochastic frontier analysis to test the pricing efficiency of IPOs, this article finds that the registration system reform works well. It improves the efficiency of Chinese IPO pricing. Also, underwriter reputation has a negative impact on IPO pricing efficiency.

Under the background of the development of new media technology, the attention of wushu events in the society is gradually increasing, which makes the competition in the event broadcasting market more and more intense. This paper focuses on the problem of predicting the operational risk of wushu event broadcasting rights, based on the GBRT algorithm, innovatively improves the traditional loss function, introduces the regular term, and proposes the application of XGBoost algorithm in the operational risk prediction of wushu event broadcasting rights. The improved algorithm divides the operational risk of broadcasting rights into two main levels, covering three primary and 10 secondary indicators. In this study, the XGBoost algorithm is applied in the early warning of informing proper operation risk, which is classified into two main levels, covering 3 primary and 10 secondary indicators. The article also conducts an in-depth experimental analysis of the risk of overpremium of the event rights and the risk of matching the audience’s demand. In addition, according to the results of audience analysis, men have become the primary audience of wushu events, with a frequency of up to 401 times. Based on the XGBoost algorithm, the wushu event broadcasting right operation risk warning system can effectively predict and help the event broadcasting platform to avoid the potential operation risk, which provides valuable data support for the market decision-making.

This paper describes the dynamic propagation process of the influence of public service advertisements (PSAs) using the information dissemination model and proposes a click probability function by modeling the click rate of advertisements, which is solved by a heuristic method. The EPR advertisement recommendation algorithm is selected to simulate the push process of the advertisement, and the experimental performance is analyzed. Analyze the presentation of Shaanxi regional culture and the network mobilization mechanism model of enterprise public service advertisement, predict and analyze the click rate of public service advertisement broadcasting, and emphasize the trust analysis of the audience. Variables such as the number of effective viewing of advertisements, the number of link clicks, the number of likes, and the amount of placement are selected to carry out descriptive analysis and correlation analysis of the effect of PSAs on Shaanxi regional culture. From the correlation coefficient matrix, it can be seen that the correlation coefficients between the explanatory variables take smaller values and are at the level below 0.11, and the number of likes has significant positive correlation coefficients with the indicators of advertisement effect at each stage. Thus it can be verified that the social attributes of advertisements play a positive role in the effect of advertisements.

Objective: The feasibility of the determination of glutamate purity was studied by differential scanning calorimetry. Methods: Indium and Zinc were used to correct the instrument parameters. Under the conditions of nitrogen atmosphere and flow rate of 50 mL/min, the effects of sample particle size, experimental atmosphere, heating rate and sample quality on the DSC measurement results were investigated, and the glutamic acid purity was determined under the optimal conditions. The determination results were compared between DSC and China Pharmacopeia 2015 titration. Results: Under the condition of weighing 3 mg and heating rate at 40 ℃/min, the purity of glutamic acid was 99.74% and the precision was 0.07%. The purity of glutamic acid measured by titration 99.72%. Conclusion: The DSC method has high accuracy and simple operation, and can be used for the determination of glutamate purity.

Breast cancer has a high occurrence rate globally and its treatment has demonstrated clinical efficacy with the use of systemic chemotherapy and immune checkpoint blockade. Insufficient cytotoxic T lymphocyte infiltration and the accumulation of immunosuppressive cells within tumours are the primary factors responsible for the inadequate clinical effectiveness of breast cancer treatment. The stimulator of interferon genes (STING) represents a pivotal protein in the innate immune response. Upon activation, STING triggers the activation and enhancement of innate and adaptive immune functions, resulting in therapeutic benefits for malignant tumours. The STING signalling pathway in breast cancer is influenced by various factors such as deoxyribonucleic acid damage response, tumour immune microenvironment, and mitochondrial function. The use of STING agonists is gaining momentum in breast cancer research. This review provides a comprehensive overview of the cyclic guanosine monophosphate-adenosine monophosphate synthase-STING pathway, its agonists, and the latest findings related to their application in breast cancer.

Excessive accumulation of nitrate (NO3-) can lead to eutrophication and ecological degradation, while also posing potential hazards to human health. The conventional Haber-Bosch process for ammonia synthesis, while effective, comes with a heavy environmental toll due to its energy consumption and greenhouse gas emissions. Fortunately, electrocatalytic nitrate reduction (NO3RR) offers a greener alternative, converting nitrates into nitrogen and ammonia, thus curbing environmental pollution while enabling ammonia recycling. MXene, characterized by its high conductivity, large specific surface area, and abundant surface functional groups, emerges as a promising catalytic material for NO3RR applications. This review offers an in-depth investigation into the application of MXene-based materials in NO3RR, elucidating strategies to enhance MXene catalytic efficiency through surface functionalization, defect engineering, and composite material synthesis. The challenges and future research directions for MXene in NO3RR are outlined. The aim is to provide a theoretical framework and practical guidance for the design and improvement of NO3RR catalysts, with the goal of enhancing their reaction efficiency and sustainability.

ObjectiveTo investigate a foodborne disease outbreak and identify the pathogenic factors in order to prevent the occurrence of similar incidents.MethodsEpidemiological study， on-site food hygiene investigation， and laboratory testing were used to analyze the cause of outbreak in Company A.ResultsA total of 24 confirmed cases were screened out. The major clinical symptoms were diarrhea （100.0%）， stomachache （100.0%）， and vomiting （41.7%）. Samples from 24 patients were tested positive for Vibrio parahaemolyticus， and were homologous by Pulsed field gel electrophoresis （PFGE） phylogenetic study. According to the result of case-control study， eating glass noodles salad at the dinner and supper on July 16th， 2019 was the risk factor （OR=15.71，95%CI：1.90‒129.71）.ConclusionThis foodborne disease outbreak was caused by glass noodles salad cross contaminated with Vibrio parahaemolyticus.

Super-resolution optical microscopy, which gives access to finer details of objects, is highly desired for fields of nanomaterial, nanobiology, nanophotonics, etc. Many efforts, including tip optimization and illumination optimization etc., have been made in both near-field and far-field super-resolution microscopy to achieve a spatial resolution beyond the diffraction limit. The development of vector light fields opens up a new avenue for super-resolution optical microscopy via special illumination modes. Cylindrical vector beam (CVB) has been verified to enable resolution improvement in tip-scanning imaging, nonlinear imaging, stimulated emission depletion (STED) microscopy, subtraction imaging, superoscillation imaging, etc. This paper reviews recent advances in CVB-based super-resolution imaging. We start with an introduction of the fundamentals and properties of CVB. Next, strategies for CVB based super-resolution imaging are discussed, which are mainly implemented by tight focusing, depletion effect, plasmonic nanofocusing, and polarization matching. Then, the roadmap of super-resolution imaging with CVB illumination in the past two decades is summarized. The typical CVB-based imaging techniques in fields of both near-field and far-field microscopy are introduced, including tip-scanning imaging, nonlinear imaging, STED, subtraction imaging, and superoscillation imaging. Finally, challenges and future directions of CVB-illuminated super-resolution imaging techniques are discussed.

To improve the NO-CO low-temperature selective catalytic reduction (SCR) denitration rate, finding new effective denitration catalysts has become the focus of the denitration field. A vanadium-substituted molecular sieve AM-6 was synthesized by hydrothermal method, the performance of AM-6 molecular sieve was improved by surfactant-assisted synthesis. The effect of different amounts of CTAB on the morphology, composition and the catalytic reduction performance was studied. These catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results show that the addition of CTAB does not introduce other impurity elements. When the ratio of CTAB to V is 1:4, AM-6(1/4CTAB) has more regular surface morphology, better crystalline formability, well-balanced ratio of V5+/V4+, and the denitrification activity reaches 81.54% at 150℃, which is reduced by 50℃ than the temperature at which the denitrification activity of AM-6 reaches 80%.

C32H54O4, monoclinic, P21 (no. 4), a = 7.8727(1) Å, b = 19.9173(2) Å, c = 19.1801(2) Å, β = 94.539(1)°, V = 2998.06(6) Å3, Z = 4, Rgt(F) = 0.0370, wRref(F2) = 0.0983, T = 293 K.

C31H50N2O2S, orthorhombic, P212121 (no. 19), a = 11.9922(9) Å, b = 16.7099(8) Å, c = 29.1262(16) Å, V = 5836.6(6) Å3, Z = 8, Rgt(F) = 0.0654, wRref(F2) = 0.1230, T = 293(2) K.

Objective To investigate the application, safety and effectiveness of "rivets" technique in endovascular therapy of internal carotid artery anterior wall anuerysms. Methods A retrospective study was carried on 8 patients suffered from aneurysm in anterior wall of the internal carotid artery and treated by endovascular therapy with rivets technique in our department from January 2010 to May 2018. Their clinical data, postoperative cerebral angiography, and clinical outcomes by follow-up digital subtraction angiography (DSA) were collected and analyzed. Results All aneurysms in the 8 patients were safely and successfully embolized during the operation, and no intraoperative aneurysm rupture happened. One patient was found having a little residual of aneurysm neck in the DSA results in 1 week, 3 months and 6 months after the operation, and this patient was followed up further since the coil was stable in form. DSA reexamination in 6 months after operation showed the other 7 patients had well repaired carotid artery intima, indicating that the aneurysm was cured completely. Conclusion The "riveting" technology can enhance the anti-impact ability of the coil at the neck of aneurysm. Combined with the stent guiding the blood flow, the technology can safely and effectively treat these easily ruptured aneurysms.

The transverse free vibration model of the rubber conveyor belt with the steel rope core is established based the small deflection theory of the orthogonal anisotropy sheet model. By using the classical solution method, the analytical solutions of the SFSF boundary model of the lower branch conveyor belt, the SCSC boundary model of the upper branch slot shape bottom, and the SFSC boundary model of the side. The main stiffness of the conveyor belt with the steel rope core is derived by using the Khobar approximation. The previous-order natural frequencies of the lower branch conveyor belt and the upper branch conveyor belt, the vibration type and the variation law of natural frequency with the tension variation are obtained by employing the numerical analysis. The results show that the natural frequencies of the lower and the upper branch of the conveyor belt increase with the increasement of the belt tension, and the tension influences the frequency of the lower branch conveyor belt greatest and the frequency of the upper branch conveyor belt bottom smaller. The researching results provide the bending vibration response analysis and the resonance avoiding design of the conveyor belt with the basis.

Few studies have reported the relationship between wild (Olea europaea L. subsp. europaea var. sylvestris) and cultivated (Olea europaea L. subsp. europaea var. europaea) olive trees by using diverse markers. Herein, the amino and fatty acids composition of stones from wild and cultivated olives were assessed respectively using amino acids analyzer and gas chromatography coupled with mass spectrometry. Stones of 24 Tunisian olive samples including twelve cultivated trees and twelve wild trees were obtained from olives harvested at ripe stage. Results showed that 17 amino acids (with eight essential amino acids) and 15 fatty acids (eight saturated and seven unsaturated) were detected in the both olive taxa. Statistically, significant differences among wild and cultivated stones were observed for amino and fatty acids contents. Based on the major fatty acids and the essential amino acids, multivariate analyses classified olive varieties into three groups showing a close relationship between some wild and cultivated olive trees. Results were useful to distinguish some interest wild olive genotypes having stones richer in essential amino acids and monounsaturated fatty acids. Wild olive trees would constitute a genetic pool of interest criteria. These data would be used as complementary tool to morphological traits and molecular markers studies providing a relationship between the cultivated and wild olive trees.

The positions and magnitudes of deuterium offsets between bulk xylem and corresponding source waters are under debate and quantifying them is essential for isotope-based ecohydrological investigations. In this study, stable isotopes (δ2H, δ18O, and δ13C), iteration method, and rehydration experiments were combined to quantitatively determine the magnitude of cryogenic vacuum extraction (CVE)- and radial water transport (RWT)-induced deuterium offsets using one riparian tree species Salix babylonica L. A modified potential water source line (MPWL) was proposed to identify the total δ2H offsets between bulk xylem and source waters. The relationships between δ2H offsets induced by CVE or RWT and plant water content, leaf δ13C values, soil water content (SWC), and the depth to the water table (WTD) were investigated. Results showed that the bulk xylem waters in different tissue positions of S. babylonica showed −7.0 ‰ to −4.0 ‰ deuterium depletion relative to MPWL at four different sites (p < 0.01). The isotopic compositions of sap water coincided well with MPWL on the dual-isotope plot at the four sites. The CVE- and RWT-induced δ2H offsets accounted for 75.1 % and 24.9 % of the total δ2H offsets, respectively. The CVE-induced δ2H offsets were significantly negatively correlated with plant water content. In comparison, the RWT-induced δ2H offsets were negatively related to plant leaf δ13C values, trunk water content, and SWC, but positively correlated with WTD. This study provides a quantitative contribution of two major sources of deuterium offsets. The results provide critical insights into isotope-based plant water source identification and evapotranspiration partitioning.

The key parameter to determine whether jadeitite can be named gem grade jadeitite 'jadeite jade' or not is the content (the mass fraction) of jadeite in jadeitite. So far, most methods to determine the mass fraction of mineral in rock are destructive, which is not suitable in gem detection. Based on the changes of mineral composition and mass fraction of mineral in jadeitite, a non-destructive method by measuring the relative density of jadeitite was established in order to get the mass fraction of jadeite. By Static Water Density Method, 186 pieces of jadeitite samples with relative densities of 3.30-3.24 were divided into groups according to different densities. The main mineral composition and mass fraction of minerals in jadeitite were analyzed by X-ray Powder Diffraction, Manual Heavy-sand Analysis, Electron Probe Microanalysis, Infrared Spectrometry and Raman Spectrometry. The linear relationship between the mass fraction of jadeite and the relative density of jadeitite was statisticstically analyzed. Results show that the main minerals in jadeitite are jadeite, albite, and analcite. As the mass fraction (wA) of jadeite decreases, those of albite and analcime increase, and the measured specific gravities (SG) of jadeitite change accordingly. The relationship between them is wA=1.3454 SG-3.4531 (r=0.9814), showing a good linear dependence relation. Because the measured specific gravity of jadeitite is approximately equal to the theoretical one, mass fraction of jadeite is obtained by measuring the specific gravity of jadeitite. This non-destructive method applies to jadeitite with a specific gravity of 3.3-3.0, jadeite content of 95%-60%, and sum mass fractions of jadeite and albite of 90%-97%.