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Multimodal learning analytics (MMLA), which has become increasingly popular, can help provide an accurate understanding of learning processes. However, it is still unclear how multimodal data is integrated into MMLA. By following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, this paper systematically surveys 346 articles on MMLA published during the past three years. For this purpose, we first present a conceptual model for reviewing these articles from three dimensions: data types, learning indicators, and data fusion. Based on this model, we then answer the following questions: 1. What types of data and learning indicators are used in MMLA, together with their relationships; and 2. What are the classifications of the data fusion methods in MMLA. Finally, we point out the key stages in data fusion and the future research direction in MMLA. Our main findings from this review are (a) The data in MMLA are classified into digital data, physical data, physiological data, psychometric data, and environment data; (b) The learning indicators are behavior, cognition, emotion, collaboration, and engagement; (c) The relationships between multimodal data and learning indicators are one-to-one, one-to-any, and many-to-one. The complex relationships between multimodal data and learning indicators are the key for data fusion; (d) The main data fusion methods in MMLA are many-to-one, many-to-many and multiple validations among multimodal data; and (e) Multimodal data fusion can be characterized by the multimodality of data, multi-dimension of indicators, and diversity of methods.

Acetic acid is an important bulk chemical that is currently produced via methanol carbonylation using fossil based CO. Synthesis of acetic acid from the renewable and cheap CO 2 is of great importance, but state of the art routes encounter difficulties, especially in reaction selectivity and activity. Here we report a route to produce acetic acid from CO 2 , methanol and H 2 . The reaction can be efficiently catalysed by Ru–Rh bimetallic catalyst using imidazole as the ligand and LiI as the promoter in 1,3-dimethyl-2-imidazolidinone (DMI) solvent. It is confirmed that methanol is hydrocarboxylated into acetic acid by CO 2 and H 2 , which accounts for the outstanding reaction results. The reaction mechanism is proposed based on the control experiments. The strategy opens a new way for acetic acid production and CO 2 transformation, and represents a significant progress in synthetic chemistry. Industrial routes to acetic acid use carbon monoxide for the carbonylation of methanol. Here, the authors report a hydrocarboxylation method that instead uses carbon dioxide and hydrogen for the conversion of methanol into acetic acid.

Fluorescence imaging has revolutionized biomedical research over the past three decades. Its high molecular specificity and unrivalled single-molecule-level sensitivity have enabled breakthroughs in a number of research fields. For in vivo applications its major limitation is its superficial imaging depth, a result of random scattering in biological tissues causing exponential attenuation of the ballistic component of a light wave. Here, we present fluorescence imaging beyond the ballistic regime by combining single-cycle pulsed ultrasound modulation and digital optical phase conjugation. We demonstrate a near-isotropic three-dimensional localized sound–light interaction zone. With the exceptionally high optical gain provided by the digital optical phase conjugation system, we can deliver sufficient optical power to a focus inside highly scattering media for not only fluorescence imaging but also a variety of linear and nonlinear spectroscopy measurements. This technology paves the way for many important applications in both fundamental biology research and clinical studies. Researchers show that digital optical phase conjugation can be used to achieve focusing at record depths in highly scattering media, and report fluorescence imaging beyond the ballistic regime with a three-dimensional confined sound-modulation zone.

Multiphoton microscopy is the current method of choice for in vivo deep-tissue imaging. The long laser wavelength suffers less scattering, and the 3D-confined excitation permits the use of scattered signal light. However, the imaging depth is still limited because of the complex refractive index distribution of biological tissue, which scrambles the incident light and destroys the optical focus needed for high resolution imaging. Here, we demonstrate a wavefront-shaping scheme that allows clear imaging through extremely turbid biological tissue, such as the skull, over an extended corrected field of view (FOV). The complex wavefront correction is obtained and directly conjugated to the turbid layer in a noninvasive manner. Using this technique, we demonstrate in vivo submicron-resolution imaging of neural dendrites and microglia dynamics through the intact skulls of adult mice. This is the first observation, to our knowledge, of dynamic morphological changes of microglia through the intact skull, allowing truly noninvasive studies of microglial immune activities free from external perturbations. Significance Multiphoton microscopy has been the gold standard for in vivo deep-tissue imaging. The long laser wavelength suffers less scattering, and the 3D-confined excitation permits the use of scattered signal light, which greatly improves the imaging depth. However, the direct application of this method to highly turbid media has been limited. Here, we present a microscope system demonstrating high resolution in vivo imaging inside highly turbid tissue. We use advanced wavefront correction with an adaptive correction plane-positioning system to compensate high-order aberrations over an extended corrected field of view. Using this technique, we demonstrate submicron-resolution imaging of neural dendrites and microglia dynamics through the intact skulls of adult mice.

The sweet taste receptor, which was identified approximately 20 years ago, mediates sweet taste recognition in humans and other vertebrates. With the development of genomics, metabonomics, structural biology, evolutionary biology, physiology, and neuroscience, as well as technical advances in these areas, our understanding of this important protein has resulted in substantial progress. This article reviews the structure, function, genetics, and evolution of the sweet taste receptor and offers meaningful insights into this G protein–coupled receptor, which may be helpful guidances for personalized feeding, diet, and medicine. Prospective directions for research on sweet taste receptors have also been proposed.

To investigate the petrogenesis of cyclic units in layered intrusions, we examined chromitite, dunite, poikilitic harzburgite and bronzitite from the Ultramafic Zone of the Stillwater Complex and measured stable isotopes of Li and O in their major minerals. The Li isotopes in olivine range from 4 to 26‰ in δ7Li with uniform Li contents of 1–3 ppm, whereas orthopyroxene and clinopyroxene have Li contents of 0.5–5 ppm and 4–8 ppm, and δ7Li ranges of −13 to 7‰ and −14 to −6‰, respectively. The δ18O values vary from 4.91 to 5.72‰ in olivine, from 5.11 to 5.87‰ in orthopyroxene, and from 4.64 to 5.86‰ in clinopyroxene. For a given sample, olivine displays more variable and higher δ7Li but lower δ18O values than orthopyroxene, indicating that olivine experienced more extensive compositional modification after crystallization relative to orthopyroxene. The general Li and O isotopic compositions are interpreted as the result of re-equilibration between interstitial liquids, from which pyroxenes crystallized, and cumulus minerals. The inter-mineral and inter-sample isotopic variations correlate with mineral assemblages, crystal sizes and major and trace element compositions, revealing that the interstitial liquids varied compositionally mainly due to mixing between fractionated magma and newly injected primitive magma. Abrupt mineralogical and geochemical changes from silicate rocks to chromitites imply that hydrous fluids, which collected on chromite surfaces and were later released from chromite seams, played an additional, critical medium of chemical exchange between minerals in the chromitites.

Summary The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4′‐deoxyflavones, which are reported to have many health‐promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4′‐deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side‐effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O‐methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3′‐hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7‐methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6‐hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co‐expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4′‐deoxyflavone substrates are supplied in the medium. Co‐expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.

Background Helicobacter pylori ( H. pylori ) infection is associated with remodeling of gut microbiota. Many studies have found H. pylori infection and eradication therapy can alter the gut microbiota. However, few studies explored the impact of eradication therapy containing minocycline and metronidazole on gut microbiota. Aim The objective of the present study was to explore the changes of gut microbiota after H. pylori infection. Besides, learn more about the dynamic changes of gut microbiota during different stages of eradication treatment containing minocycline, metronidazole, bismuth agents and proton pump inhibitors. Methods Sixty stool samples from the patients with H. pylori infection before eradication, 14 and 42 days after eradication, and ten stool samples from non-infected individuals were collected. Subsequently, we performed 16S rRNA gene amplicon sequencing to analyze these samples, and the results were evaluated by using alpha diversity, beta diversity and microbial composition analyses. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was also used to predict the metabolic pathways according to the Kyoto Encyclopedia of Genes and Genomes database. Results The alpha and beta diversity of the microbiota changed significantly in H. pylori infected individuals, but returned to baseline 42 days after eradication therapy. At the genus level, the abundances of Bacteroidetes , [Ruminococcus]_gnavus_group , Ruminococcaceae_Incertae_Sedis , Tuzzrealla , Butyricicoccus were significantly lower in the H. pylori infected group. Bacterial abundance was also dynamically changing during eradication treatment. In addition, PICRUST analysis found the levels of uronic acid metabolism, uncharacterized transport system, and biosynthesis of unsaturated fatty acids were higher in H. pylori infected individuals than in the non-infected group. Conclusions Intestinal microbiota diversity, composition, functional predictions altered significantly after H. pylori infection, and gradually returned to healthy control levels after the application of eradication therapy containing minocycline and metronidazole in one month and a half.

Sweet taste receptors (STRs) are class C G protein-coupled receptors (GPCRs) that function as heterodimers of TAS1R2 and TAS1R3. These receptors possess multiple binding sites and can be activated by a wide range of sweet-tasting compounds. Interestingly, TAS1R2 alone or even its extracellular domain-truncated form (TAS1R2-TMD), can act as a functional receptor. Previous studies demonstrated that the sweetener S819 and the sweet inhibitor amiloride act through the transmembrane domain (TMD) of TAS1R2; however, the molecular mechanisms underlying these ligand-specific effects remain unclear, largely due to the historical lack of experimentally determined full-length STR structures. Recent breakthroughs in cryo-EM structural determination of the full-length TAS1R2/TAS1R3 complex now offer an unprecedented opportunity to elucidate receptor activation mechanisms at atomic resolution. In this study, we investigated ligand-induced conformational dynamics of hTAS1R2-TMD using microsecond-scale molecular dynamics (MD) simulations on three systems: hTAS1R2-TMD/S819 (agonist-bound), hTAS1R2-TMD/amiloride (antagonist-bound), and hTAS1R2-TMD (apo). Comparative analyses revealed that agonist and antagonist binding distinctly modulate key structural switches, including the conserved ionic lock (E6.35-R3.50), which stabilizes the inactive state and disrupts upon activation. Notably, we identified a novel salt bridge (D7.32-R3.32) that forms preferentially in the active state, potentially serving as a unique molecular switch for TAS1R2. Additional analyses uncovered ligand-specific rearrangements in hydrogen-bonding and hydrophobic interaction networks. These results provide atomistic insights into how agonists and antagonists differentially modulate TAS1R2 activation and lay a structural foundation for designing novel sweeteners and taste modulators.

Assessing axillary lymph node (ALN) tumor burden (low burden: < 3 positive ALNs; high burden: ≥ 3 positive ALNs) preoperatively is essential for guiding treatment strategies. This study aimed to develop a radiomics-based nomogram by integrating clinical data, serologic markers, ultrasound imaging features, and ultrasound-derived radiomics features to predict axillary lymph node metastatic burden in breast cancer. A study was conducted on 234 breast cancer patients. Univariate and multivariate logistic regression analyses were used to identify independent risk factors from ultrasound imaging and clinical pathology, constructing a clinical model. Radiomics features were extracted from ultrasound images, and the best features were selected using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm to construct the Radiomics score. The Radiomics nomogram model was built by combining the Radiomics score and independent risk factors from the clinical model. The performance of the clinical model, radiomics model, and combined model in predicting axillary lymph node tumor burden was evaluated. Model performance was assessed by discrimination, calibration curves, and decision curves. Results showed that US-reported ALN status and CA153 were independent risk factors for high ALN tumor burden. The radiomics nomogram demonstrated good calibration and discrimination, with an area under the ROC curve of 0.815 (95% CI, 0.755-0.876) for the training set and 0.808 (95% CI, 0.678-0.938) for the testing set. Furthermore, compared to the clinical model and radiomics model, The differences in AUC between the nomogram model and the clinical model, as well as between the nomogram model and the radiomics model, were not statistically significant (nomogram model vs. clinical model: P = 0.2078; nomogram model vs. radiomics model: P = 0.4161). But the nomogram model provided greater net benefit for all patients in the probability threshold range of 0.05-0.70. This study highlights the potential of an ultrasound-based radiomics nomogram as a robust and non-invasive predictive tool for evaluating ALN tumor burden, offering valuable guidance for personalized treatment planning in breast cancer.