Abstract College physics course based on online teaching system can make the boring theoretical derivation process more intuitive and convenient with the help of the unique characteristics of multimedia technology and tools, so that students’ learning efficiency can be significantly improved, so it has high research value. Based on this, this paper first analyses the current situation and existing problems of college physics course teaching, then studies the necessity of constructing college physics online teaching platform, and finally gives the construction strategy of college physics online teaching system based on the construction of curriculum group.
Parkinson's disease (PD) is a common neurodegenerative disease that is characterized by pathological dopaminergic (DA) neuronal death and α-synuclein aggregation. Glutamate excitotoxicity is a well-established pathogenesis of PD that involves dysfunctional expression of glutamate transporters. Glutamate transporter-1 (GLT-1) is mainly responsible for clearance of glutamate at synapses, including DA synapses. However, the role of GLT-1 in the aberrant synaptic transmission in PD remains elusive. In the present study, we generated small-interfering RNAs (siRNAs) to knockdown GLT-1 expression in primary astrocytes, and we report that siRNA knockdown of astrocytic GLT-1 decreased postsynaptic density-95 (PSD-95) expression in neuron-astrocyte cocultures in vitro. Using adeno-associated viruses (AAVs) targeting GLT-1 short-hairpin RNA (shRNA) sequences with a glial fibrillary acidic protein (GFAP) promoter, we abolished astrocytic GLT-1 expression in the substantia nigra pars compacta (SNpc) of mice. We found that GLT-1 deficiency in the SNpc induced parkinsonian phenotypes in terms of progressive motor deficits and nigral DA neuronal death in mice. We also found that there were reactive astrocytes and microglia in the SNpc upon GLT-1 knockdown. Furthermore, we used RNA sequencing to determine altered gene expression patterns upon GLT-1 knockdown in the SNpc, which revealed that disrupted calcium signaling pathways may be responsible for GLT-1 deficiency-mediated DA neuronal death in the SNpc. Taken together, our findings provide evidence for a novel role of GLT-1 in parkinsonian phenotypes in mice, which may contribute to further elucidation of the mechanisms of PD pathogenesis.
Glutamate transporters play a key role in glutamate clearance and protect the central nervous system from glutamate excitotoxicity. Dysfunctional glutamate transporters contribute to the pathogenesis of Parkinson's disease (PD); however, the mechanisms that underlie the regulation of glutamate transporters in PD are still not well characterized. Here we report that Nedd4-2 mediates the ubiquitination of glutamate transporters in 1-methyl-4- phenylpyridinium (MPP+)-treated astrocytes and in the midbrain of 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP)-constructed PD model mice. Nedd4-2-mediated ubiquitination induces abnormal glutamate transporter trafficking between the membrane and cytoplasm and consequently decreases the expression and function of glutamate transporters in the membrane. Conversely, Nedd4-2 knockdown decreases glutamate transporter ubiquitination, promotes glutamate uptake and increases glutamate transporter expression in vitro and in vivo. We report for the first time that Nedd4-2 knockdown ameliorates movement disorders in PD mice and increases tyrosine hydroxylase expression in the midbrain and striatum of PD mice; Nedd4-2 knockdown also attenuates astrogliosis and reactive microgliosis in the MPTP model that may be associated with glutamate excitotoxicity. Furthermore, the SGK/PKC pathway is regulated downstream of Nedd4-2 in MPTP-treated mice. These findings indicate that Nedd4-2 may serve as a potential therapeutic target for the treatment of PD.
Objective To investigate the mechanism underlying the immunosuppressive effect and its reverse of γδ1 T cells derived from breast cancer tissues by inducing immunosenescence. Methods After γδ1 T cells isolated from breast cancer tissues were co-cultured with peripheral blood-derived naive CD4+ T cells, the proliferation of treated CD4+ T cells was detected by CCK-8 assay, and the activity of senescence-associated β-galactosidase (SA-β-Gal) in treated CD4+ T cells was detected by SA-β-Gal staining. After the induced senescent CD4+ T cells were co-cultured with the naive CD4+ T cells, the proliferation, apoptosis, activity of the treated CD4+ T cells were examined by CCK-8 assay, flow cytometry and SA-β-Gal staining, respectively; the expression of cell cycle-associated proteins P53, P21 and P16 in the treated CD4+ T cells was detected by Western blot analysis in order to verify the immunosuppressive effect of the senescent CD4+ T cells. The expression levels of inhibitory cytokines interleukin 17D (IL-17D), IL-10, transforming growth factor-α (TGF-α) and so on, in the supernatant were analyzed by cytokine microarray after co-culture of γδ1 T cells with naive CD4+ T cells. After the co-culture system of γδ1 T cells and naive CD4+ T cells was treated with anti-IL-17D monoclonal antibody, the proliferation of the naive CD4+ T cells was determined by CCK-8 assay. The level of IL-17D secreted by γδ1 T cells treated by single-stranded RNA40 (ssRNA40), the ligand of Toll like receptor 8 (TLR8) and TLR8 short hairpin RNA (shRNA) lentiviral vector was detected by ELISA. The effects of ssRNA40 on the immunosenescence induced by γδ1T cells were confirmed by SA-β-Gal staining and Western blot analysis. Results γδ1 T cells derived from breast cancer tissues induced the immunosenescence of the naive CD4+T cells, and the senescent CD4+ T cells further exerted the immunosuppressive effect. The results of cytokine microarray showed that IL-17D concentration was at the highest level among inhibitory cytokines in the supernatant of γδ1 T cells from breast cancer tissues. The inhibitory effect of γδ1 T cells on the proliferation of CD4+ T cells could be reduced by anti-IL-17D monoclonal antibody. TLR8 ligand ssRNA40 inhibited the secretion of IL-17D, and then partially reversed the proliferating inhibition on the naive CD4+ T cells and immunosenescent induction by γδ1 T cells. Conclusion The γδ1 T cells derived from breast cancer tissues exert immunosuppressive effect by producing IL-17D to induce the immunosenescence of the naive CD4+ T cells. TLR8 ligand ssRNA40 can partially reduce the level of IL-17D secreted by γδ1 T cells, which can partially reverse the senescence and immunosuppression effect of γδ1 T cells on naive CD4+ T cells.
Surface soil moisture (SSM) plays a pivotal role various fields, including agriculture, hydrology, water environment, and meteorology. To investigate the impact of land use types and fractional vegetation cover (FVC) on the accuracy of SSM estimation, this study conducted a comprehensive analysis of SSM estimation performance across diverse land use scenarios (e.g., multiple land use combinations and cropland) and varying FVC conditions. Sentinel-2 NDVI and MOD09A1 NDVI were fused by the Enhanced Spatial and Temporal Adaptive Reflection Fusion Model (ESTARFM) to obtain NDVI with a temporal resolution better than 8 d and a spatial resolution of 20 m, which improved the matching degree between NDVI and the Sentinel-1 backscattering coefficient (σ0). Based on the σ0, NDVI, and in situ SSM, combined with the water cloud model (WCM), the SSM estimation model is established, and the model of each land use and FVC is validated. The model has been applied in Handan. The results are as follows: (1) Compared with vertical–horizontal (VH) polarization, vertical–vertical (VV) polarization is more sensitive to soil backscattering (). In the model for multiple land use combinations (Multiple-Model) and the model for the cropland (Cropland-Model), the R2 increases by 0.084 and 0.041, respectively. (2) The estimation accuracy of SSM for the Multiple-Model and Cropland-Model is satisfactory (Multiple-Model, RMSE = 0.024 cm3/cm3, MAE = 0.019 cm3/cm3, R2 = 0.891; Cropland-Model, RMSE = 0.023 cm3/cm3, MAE = 0.018 cm3/cm3, R2 = 0.886). (3) When the FVC > 0.75, the accuracy of SSM by the WCM is low. It is suggested the model should be applied to the cropland where the FVC ≤ 0.75. This study clarified the applicability of SSM estimation by microwave remote sensing (RS) in different land uses and FVCs, which can provide scientific reference for regional agricultural irrigation and agricultural water resources management. The findings highlight that the VV polarization-based model significantly improves SSM estimation accuracy, particularly in croplands with FVC ≤ 0.75, offering a reliable tool for optimizing irrigation schedules and enhancing water use efficiency in agriculture. These results can aid in better water resource management, especially in regions with limited water availability, by providing precise soil moisture data for informed decision-making.
Based on the existing image mosaic technology, this paper introduces the granular computing and obtains a simplified new algorithm. The image mosaic executed by this algorithm at first establishes correlation model on the basis of granular computing theory, and obtains edge map of each image needing mosaic. The new calculation method is used to calculate gradient of in different columns of edge map, to obtain the feature point coordinates with the maximum gradient; meanwhile, all feature points of two images are matched with each other, to acquire the best matching point. In addition, the error-correcting mechanism is introduced in the matching process, which is used to delete feature points with matching error. The correlation calculation is carried out for the matching pixels acquired by the above processing, to get the feature transformational matrix of the two images. According to the matrix, two separated image maps map into the same plane. The slow transitional mosaic method is applied in the aspect of image addition plus overlap removal, so that images have no bulgy boundary after mosaics. The whole image mosaic process shows that the given granular computing algorithm is superior to the traditional one both in the number of processed images and the number of processing, and the mosaic image gained has high quality.
The quality of innovative talents cultivation plays a decisive role in the rise and fall of the country and the survival of a nation.As an important base for cultivating talents,colleges and universities have their unshirkable responsibilities to shoulder the sacred mission of cultivating innovative talents.This paper analyzes the current situation of university students' creativity training by questionnaire,proposes many solutions to improve university students' innovative ability from several aspects,such as creating a positive campus atmosphere for innovation,striving to build high-quality faculty and promoting the teaching reform on innovative talents cultivation,etc.
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