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In current smart classroom research, numerous studies focus on recognizing hand-raising, but few analyze the movements to interpret students' intentions. This limitation hinders teachers from utilizing this information to enhance the effectiveness of smart classroom teaching. Assistive teaching methods, including robotic and artificial intelligence teaching, require smart classroom systems to both recognize and thoroughly analyze hand-raising movements. This detailed analysis enables systems to provide targeted guidance based on students' hand-raising behavior. This study proposes a morphology-based analysis method to innovatively convert students' skeleton key point data into several one-dimensional time series. By analyzing these time series, this method offers a more detailed analysis of student hand-raising behavior, addressing the limitations of deep learning methods that cannot compare classroom hand-raising enthusiasm or establish a detailed database of such behavior. This method primarily utilizes a neural network to obtain students' skeleton estimation results, which are then converted into time series of several variables using the morphology-based analysis method. The YOLOX and HrNet models were employed to obtain the skeleton estimation results; YOLOX is an object detection model, while HrNet is a skeleton estimation model. This method successfully recognizes hand-raising actions and provides a detailed analysis of their speed and amplitude, effectively supplementing the coarse recognition capabilities of neural networks. The effectiveness of this method has been validated through experiments.
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Mano , Motivación , Redes Neurales de la Computación , Estudiantes , Humanos , Mano/fisiología , Motivación/fisiología , Movimiento/fisiología , Grabación en Video/métodos , Inteligencia ArtificialRESUMEN
Artificially intelligent robots as teachers (AI teachers) have attracted extensive attention due to their potential to relieve the challenge of global teacher shortage and realize universal elementary education by 2030. Despite mass production of service robots and discussions about their educational applications, the study of full-fledged AI teachers and children's attitudes towards them is quite preliminary. Here, we report a new AI teacher and an integrated model to assess how pupils accept and use it. Participants included students from Chinese elementary schools via convenience sampling. Questionnaires (n = 665), descriptive statistics and structural equation modeling based on software SPSS Statistics 23.0 and Amos 26.0 were carried out in data collection and analysis. This study first developed an AI teacher by coding a lesson design, course contents and Power Point with script language. Based on the popular Technology Acceptance Model and Task-Technology Fit Theory, this study identified key determinants of the acceptance, including robot use anxiety (RUA), perceived usefulness (PU), perceived ease of use (PEOU) and robot instructional task difficulty (RITD). Moreover, this study found that pupils' attitudes towards the AI teacher, which could be predicted by PU, PEOU and RITD, were generally positive. It is also found that the relationship between RITD and acceptance was mediated by RUA, PEOU and PU. This study holds significance for stakeholders to develop independent AI teachers for students.
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Solid-state luminescent materials that possess reversible fluorescence changes toward external multistimuli are of immense interest because of their potential applications in data storage and sensors. While the recent developments in this field are mainly focused on the π-conjugated organic molecules. Herein two polymorphic luminescent ionic liquid (IL)-based stimuli-responsive materials were designed by the supramolecular assemblies of an organic-decorated chlorobismuthate anion and a rotationally flexible imidazolium cation, namely, α (1)/ß (2)-[Bmmim][BiCl4(2,2'-bpy)] (Bmmim = 1-butyl-2,3-dimethylimidazolium; 2,2'-bpy = 2,2'-bipyridine). Because of the different conformations of the n-butyl chains on the imidazolium cations, tuning of the supramolecular packing structures as well as luminescent colors for 1 and 2 was realized. Single-crystal X-ray diffraction and Hirshfeld surface analyses disclose that the polymorphism-dependent emission may be attributed to the different weak interactions, especially to the π-π interactions between adjacent [BiCl4(2,2'-bpy)]- anions in two compounds. Additionally, compound 2 could be transformed into 1 spontaneously at ambient conditions, which could be triggered by the moisture in the air. Both of the title compounds could detect NH3 vapor selectively through the luminescence "turn-off" method rapidly and reversibly because of the destruction of intermolecular interactions, indicating their stimuli-responsive property toward NH3.
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A series of hybrid tellurium chlorides based on ionic liquids (ILs), namely, α-[Bmim]2TeCl6 (1, Bmim = 1-butyl-3-methyl imidazolium), ß-[Bmim]2TeCl6 (2), [HOOCMim]2TeCl6 (3, HOOCMim = 1-carboxymethyl-3-methyl imidazolium), [Bzmim]2TeCl6 (4, Bzmim = 1-benzyl-3-methyl imidazolium), [EPy]2TeCl6 (5, EPy = 1-ethylpyridinium), [Bmmim]2TeCl6 (6, Bmmim = 1-butyl-2,3-dimethyl imidazolium), have been synthesized and characterized. Different kinds of supramolecular networks have been obtained via self-assemblies of isolated [TeCl6]2- anions and various ionic liquid cations. Interestingly, all the title compounds exhibit semiconducting behaviors: their optical absorption edges calculated from reflectance spectra are in the range of 2.54-2.68 eV; their electrical conductivities measured by using two-probe direct current (DC) method indicate values from 2.06 × 10-9 to 4.65 × 10-6 S/cm, which are typical for semiconductors and comparable to the reported crystalline hybrid metal halides. The luminescent property studies reveal that only compounds 3 and 6 exhibit intense emissions both at 77 and 298 K, probably owing to the minimum distortion of the TeCl6 octahedra in 3 and 6.
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Trace elements in pearls have characteristic disciplines and functions. The previous work had paid attention to different characteristics of trace elements in freshwater and seawater cultured pearls, but only limited species of trace elements have been detected by former testing techniques and analysis methods, and the test results have not been further analyzed. With the advantages of detection in good capability and high speed, inductively coupled plasma mass spectrometer (ICP-MS) can concurrently test various trace and ultra-trace elements. In the present paper, trace elements of cultured pearls in freshwater and seawater were measured by ICP-MS, and analyzed compared by a method of data processing. The results show that: (1) The kinds of higher content of trace elements (Sr, Zn, Ni, Ba, Mn, Cr, Cu, Pb, Ti, Co, Ce, Zr, La, Rb) in cultured pearls are approximately the same, but the total amount of trace elements in freshwater cultured pearls is significantly less than that of seawater cultured pearls. (2) The content of trace elements (Sr, Mn, Ba, Ni, Cr, Pb) in freshwater cultured pearls is more regular, and has a relatively fixed sequence from high to low, namely Sr > Mn > Ba > Ni > Cr > Pb. The content of trace elements in seawater cultured pearls is quite different. Sr is enriched in all samples. There is no a stable order of contents for the other trace elements. (3) There is a significant correlation among some trace elements in cultured pearls. The conclusion is instructive to indicate cultured environment, cultured technology, identification, comprehensive development and utilization of cultured pearls.
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Oncolytic bacteria can trigger innate immune activity. However, the antitumour efficacy of inactivated bacteria is poor, and attenuated live bacteria pose substantial safety risks. Here we show that intratumourally injected paraformaldehyde-fixed bacteria coated with manganese dioxide potently activate innate immune activity, modulate the immunosuppressive tumour microenvironment and trigger tumour-specific immune responses and abscopal antitumour responses. A single intratumoural administration of mineralized Salmonella typhimurium suppressed the growth of multiple types of subcutaneous and orthotopic tumours in mice, rabbits and tree shrews and protected the cured animals against tumour rechallenge. We also show that mineralized bacteria can be administered via arterial embolization to treat orthotopic liver cancer in rabbits. Our findings support the further translational testing of oncolytic mineralized bacteria as potent and safe antitumour immunotherapeutics.
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Inmunoterapia , Salmonella typhimurium , Microambiente Tumoral , Animales , Salmonella typhimurium/fisiología , Ratones , Conejos , Inmunoterapia/métodos , Óxidos , Compuestos de Manganeso/química , Línea Celular Tumoral , Humanos , Femenino , Inmunidad InnataRESUMEN
Background: The pathogenesis of pancreatitis involves diverse environmental risk factors, some of which have not yet been clearly elucidated. This study systematically investigated the causal effects of genetically predicted modifiable risk factors on pancreatitis using the Mendelian randomization (MR) approach. Methods: Genetic variants associated with 30 exposure factors were obtained from genome-wide association studies. Summary-level statistical data for acute pancreatitis (AP), chronic pancreatitis (CP), alcohol-induced AP (AAP) and alcohol-induced CP (ACP) were obtained from FinnGen consortia. Univariable and multivariable MR analyses were performed to identify causal risk factors for pancreatitis. Results: Genetic predisposition to smoking (OR = 1.314, P = 0.021), cholelithiasis (OR = 1.365, P = 1.307E-19) and inflammatory bowel disease (IBD) (OR = 1.063, P = 0.008) as well as higher triglycerides (OR = 1.189, P = 0.016), body mass index (BMI) (OR = 1.335, P = 3.077E-04), whole body fat mass (OR = 1.291, P = 0.004) and waist circumference (OR = 1.466, P = 0.011) were associated with increased risk of AP. The effect of obesity traits on AP was attenuated after correcting for cholelithiasis. Genetically-driven smoking (OR = 1.595, P = 0.005), alcohol consumption (OR = 3.142, P = 0.020), cholelithiasis (OR = 1.180, P = 0.001), autoimmune diseases (OR = 1.123, P = 0.008), IBD (OR = 1.066, P = 0.042), type 2 diabetes (OR = 1.121, P = 0.029), and higher serum calcium (OR = 1.933, P = 0.018), triglycerides (OR = 1.222, P = 0.021) and waist-to-hip ratio (OR = 1.632, P = 0.023) increased the risk of CP. Cholelithiasis, triglycerides and the waist-to-hip ratio remained significant predictors in the multivariable MR. Genetically predicted alcohol drinking was associated with increased risk of AAP (OR = 15.045, P = 0.001) and ACP (OR = 6.042, P = 0.014). After adjustment of alcohol drinking, genetic liability to IBD had a similar significant causal effect on AAP (OR = 1.137, P = 0.049), while testosterone (OR = 0.270, P = 0.002) a triglyceride (OR = 1.610, P = 0.001) and hip circumference (OR = 0.648, P = 0.040) were significantly associated with ACP. Genetically predicted higher education and household income levels could lower the risk of pancreatitis. Conclusions: This MR study provides evidence of complex causal associations between modifiable risk factors and pancreatitis. These findings provide new insights into potential therapeutic and prevention strategies.
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Colelitiasis , Diabetes Mellitus Tipo 2 , Pancreatitis , Humanos , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Enfermedad Aguda , Pancreatitis/etiología , Pancreatitis/genética , Factores de Riesgo , Triglicéridos , Colelitiasis/epidemiología , Colelitiasis/genéticaRESUMEN
The different hydrogen bond interactions in two organic-inorganic hybrid manganese halide compounds, namely [A]2[MnBr4] (A = N-butyl-N-methylpyrrolidinium ([P14]+) for (1) and N-butyl-N-methylpiperidinium ([PP14]+) for (2)), lead to distinct photoluminescence quantum yields (81% for 1; 55% for 2). Further applications of luminescent 1 are also developed.