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Wine is a complex solution system generated by physical, chemical and biological transformation of grape berries. Traditional methods for wine authenticity identification and quality control are cumbersome and time-consuming, and therefore cannot meet the needs of mass production. Spectroscopic techniques can simplify the procedure of wine analysis, shorten the analysis time, and enable simultaneous analysis of multiple components. Therefore, spectroscopic techniques have been widely used to assess wine quality and identify the geographical origin, variety, age and authenticity of wine. Furthermore, the combination of spectroscopic techniques and chemometrics allows the identification or modeling of key chemical markers, providing rapid, accurate, non-destructive and real-time detection for wine analysis and quality control. In this article, we summarize the theoretical basis for the application of ultraviolet-visible (UV-Vis), infrared, fluorescence and Raman spectroscopy for wine analysis. Furthermore, we review the current status of the application of spectroscopic techniques in conjunction with chemometrics for wine traceability, quality control and authenticity identification. Finally, we discuss the challenges that spectroscopic techniques face when applied in practice and propose possible solutions to these challenges.

Background Shoulder-hand syndrome is one of the major disabling factors for stroke patients, which seriously affects their physical and psychological health as well as their quality of life. Currently, there are many non-pharmacologic treatments used to treat post-stroke shoulder-hand syndrome, but there is still some confusion about which non-pharmacologic treatment modality is more effective in clinical practice. Objective To provide evidence-based support for clinical decision-making, this network meta-analysis evaluates the efficacy of seven non-pharmacological treatments in improving outcomes for post-stroke shoulder-hand syndrome, pain as measured by the Visual Analogue Scale (VAS), and scores on the simplified Fugl-Meyer Assessment (FMA) . Methods A computerized search of databases including CNKI, Wanfang Data, VIP, China Biomedical Literature Service System, PubMed, Embase, and Cochrane Library was conducted for randomized controlled trials on non-pharmacological treatments for post-stroke shoulder-hand syndrome up to June 2023. Two researchers independently screened the literature and extracted data, performing the network meta-analysis using RevMan 5.3 and Stata 15.0. Results The analysis included 62 studies involving 5 090 patients, assessing interventions such as acupuncture, herbal fumigation, extracorporeal shockwave therapy, moxibustion, herbal hot compress, electrical stimulation, and herbal soak. Results showed that all seven non-pharmacological treatments were superior to the control group in improving overall effectiveness, and FMA scores (P

The van der Waals itinerant ferromagnet Fe5GeTe2 has recently aroused great attention for the promising in spintronic devices applications. For such applications, the intrinsic magnetic properties such as magnetocrystalline anisotropy and room-temperature Curie temperature play the key role, both of which depend on the localized feature of its itinerant 3d electrons of Fe. Here, we study the localized feature of the itinerant 3d electrons of Fe of Fe5GeTe2. The results of Fe5GeTe2 single crystal show that the inverse susceptibility well fits the Curie–Weiss law above the paramagnetic Curie temperature TΔ ≈ 300 K, and the saturated magnetization follows a spin wave model with a power law of 1.525 below 30 K, both of which identify the strongly localized feature. Furthermore, the Rhodes–Wohlfarth ratio of approximately 2.4 of Fe5GeTe2 is higher than the value of 2.14 of vdW itinerant ferromagnet Fe3GeTe2, implying that the localized extent of the former is slightly lower than the latter. [ABSTRACT FROM AUTHOR]

The unstructured multiple-attempt (MA) item response data in virtual learning environments (VLEs) are often from student-selected assessment data sets, which include missing data, single-attempt responses, multiple-attempt responses, and unknown growth ability across attempts, leading to a complex and complicated scenario for using this kind of data set as a whole in the practice of educational measurement. It is critical that methods be available for measuring ability from VLE data to improve VLE systems, monitor student progress in instructional settings, and conduct educational research. The purpose of this study is to explore the ability recovery of the multidimensional sequential 2-PL IRT model in unstructured MA data from VLEs. We conduct a simulation study to evaluate the effects of the magnitude of ability growth and the proportion of students who make two attempts, as well as the moderated effects of sample size, test length, and missingness, on the bias and root mean square error of ability estimates. Results show that the model poses promise for evaluating ability in unstructured VLE data, but that some data conditions can result in biased ability estimates.

Due to the excellent physical properties and advantages in the field of tumor therapy, lutetium 177 has attracted extensive attention in the field of internal radiation therapy in nuclear medicine. The carrier free radionuclide lutetium 177 can be used for targeted treatment of neuroendocrine tumor and prostate tumor. The carrier free radionuclide lutetium 177 can be prepared by irradiating high abundance ytterbium 176 isotope in reactor. The experimental study result found that the abundance of ytterbium 176 isotope directly affects the activity of lutetium 177. In order to meet the requirement of high abundance of ytterbium 176 isotope, in view of the characteristics of high primary separation coefficient and good universality of electromagnetic method, the key process parameters of electromagnetic separation and preparation of high abundance ytterbium 176 isotopes were studied. Ultra dry YbCl3 with purity of 99.99% was selected as the separation raw material according to the requirements of electromagnetic isotope separation on raw materials. The trajectory of ytterbium ion beam in magnetic field was simulated, and the effects of magnetic induction intensity and beam opening angle on the dispersion of ytterbium isotope separation were given. The results are the same as the theoretical analysis. The design of nonuniform field will increase the dispersion between isotopes, reduce the sputtering contamination between isotopes, and then improve the abundance of isotopes. The emission angle of ytterbium ion beam is 11°, the seven isotopes of ytterbium can be separated completely, and the dispersion of ytterbium 176 and ytterbium 174 is large. The effects of ion source parameter on the beam intensity and focusing ability of ytterbium isotopes were obtained by ytterbium isotope electromagnetic separation experiment. The main basis for judging whether the discharge parameters of the ion source are appropriate is the current intensity of the ytterbium 176 ion beam and the focusing ability Q of the ion beam. In this experiment, the ratio of the current intensity of the ytterbium 176 to the panel current intensity was taken as the embodiment of the focusing ability Q. This experiment was carried out by controlling the variable method, and the optimal combination of separation parameters was given. Finally, ytterbium 176 isotope sample with high abundance was prepared by electromagnetic separation. After separation, the ytterbium isotope in the receiver is chemically purified to obtain ytterbium 176 isotope, which is detected by mass spectrometer. The abundance of the sample reaches 9816%. The high abundance ytterbium 176 isotope prepared in this study is chemically treated to form Yb2O3 compound, which is used as the target of nuclear reactor irradiation to supply the demander.

Based on an analysis of the influence of the quality of fast-selling products on customers’ shopping behaviour, this paper discusses the research on the influence of various factors on customers’ shopping behaviour. According to modern scientific methods and literature, theoretical research and social factor analysis, from three angles, namely corporate image, product/service image, and consumer image, six important indicators, such as corporate image, product style and value, consumer characteristics, user’s buying feeling, corporate philosophy and corporate values, are determined, which are the key factors that influence people’s choice behaviour. Considering the key factors in the quality of fast-selling products and the weight of their influence on users’ choice behaviour, according to the development trend of the fast-selling-product industry, this paper provides appropriate guidance on shaping and ensuring the quality of enterprises’ products. Suggestions on image-building and maintenance of fast-selling products are as follows: the image-building of fast-selling products must pay attention to quality, the shaping of brand culture and the practice of brand image communication management.

Polymetallic enrichment layers are commonly found at the base of the Lower Cambrian and extensively distributed across the Upper Yangtze Platform, yet their genetic models remain controversial. This study systematically collected samples from a typical section in the southeastern Chongqing region for mineral, organic, and inorganic analyses. It investigates the relationship between the abundance of various trace metal elements and organic matter at the base of the Niutitang Formation, as well as the vertical distribution characteristics of organic carbon isotopes and organic matter features. The results indicate that the Niutitang Formation shale exhibits a distinct three-part structure from bottom to top. Various metal elements are enriched in the lower interval, showing a close correlation between the abundance of polymetallic elements and the carbon isotopes of shale organic matter. The middle interval contains the highest TOC value and the lowest Ti/Al ratio, while the upper interval shows a significant decrease in organic matter abundance, with a clear positive correlation between the excess silicon content and Ti/Al ratio. Additionally, the mixing effect of deep-sea upwelling is the primary control on the formation of polymetallic enrichment layers in the lower interval, followed by the adsorption of organic matter under anoxic conditions. The sedimentary environment of the upper interval of the Niutitang Formation trends toward oxidation, with paleoclimate shifting toward colder and drier conditions, exhibiting aeolian sedimentary features that are unfavorable for the enrichment of trace metal elements. Consequently, upwelling is a key factor in the enrichment and mineralization of trace metal elements at the base of the Lower Cambrian in the Upper Yangtze region. [ABSTRACT FROM AUTHOR]

Green purchasing behavior refers to the potential of consumers to reduce the impact on the environment and the excessive loss of natural resources in the procurement process as far as possible under the premise of meeting their own needs. This behavior is not only helpful in alleviating environmental problems but also is an important way to achieve sustainable development. However, whether consumers will increase non-green or excessive compensatory consumption behaviors due to the "moral permission" psychological tendency, present after purchasing green products, is an important question in the current research. This study explores the effect of green purchase intention on compensatory consumption behavior, with special attention to the moderating role of pro-environmental behavior in this relationship. With the increasingly severe global environmental problems, green consumption, as a pro-environmental behavior, has gradually become the focus of social attention. By analyzing the relationship between consumers' green purchase intention and their subsequent compensatory consumption behavior, this study further reveals the important role of pro-environment behavior in the consumption decision-making process. [ABSTRACT FROM AUTHOR]