Analysis of Online Teaching Mode and Effect of Computer Network under Large-Scale Users

Under the influence of the epidemic situation, many teachers and students choose the online teaching of computer network. We should study how to use the online teaching of computer network on a large scale. Based on the online teaching data of the school, this paper makes a comparative analysis of the functions and teaching methods of the computer network teaching platform. Through the feedback survey of teachers and students, most of them are satisfied with the online teaching of computer network, but there are also some problems. These problems are: teachers and students do not adapt to the new online teaching method; they are not familiar with the software of network platform, which makes it difficult to use; there are technologies in the teaching process, such as not fluent, unable to log in, unable to open web pages, etc Question. Through the continuous improvement of computer network teaching problems, teachers and students experience better and better, and their satisfaction is higher and higher. Generally speaking, online teaching of computer network has become an important teaching method, which will continue to be valued and applied in the post epidemic era

A Functional Study Identifying Critical Residues Involving Metal Transport Activity and Selectivity in Natural Resistance-Associated Macrophage Protein 3 in Arabidopsis thaliana

Arabidopsis thaliana natural resistance-associated macrophage protein 3 (AtNRAMP3) is involved in the transport of cadmium (Cd), iron (Fe), and manganese (Mn). Here, we present a structure-function analysis of AtNRAMP3 based on site-directed mutagenesis and metal toxicity growth assays involving yeast mutants, combined with three-dimensional (3D) structure modeling based on the crystal structure of the Eremococcus coleocola NRAMP family transporter, EcoDMT. We demonstrated that two conservative sites, D72 and N75, are essential for the transport activity. The M248A mutation resulted in a decrease in Cd sensitivity, while maintaining Mn transport. The mutation involving G61 caused a significant impairment of Fe and Mn transport, thereby indicating the importance of the conserved residue for proper protein function. The mutation involving G171 disrupted Fe transport activity but not that of Mn and Cd, suggesting that G171 is essential to metal binding and selectivity. Two residues, E194 and R262, may play an important role in stabilizing outward-facing conformation, which is essential for transport activity. Deletion assays indicated that the N-terminus is necessary for the function of AtNRAMP3. The findings of the present study revealed the structure-function relationship of AtNRAMP3 and metal transport activity and selectivity, which may possibly be applied to other plant NRAMP proteins

Stability analysis of seven agronomic traits for soybean [(Glycine max (L.) Merr.] Tokachi nagaha and its derived cultivars using the AMMI model

The stabilities of seven agronomic traits were analyzed and the general stabilities of soybean [Glycine max (L.) Merr.] accessions were evaluated based on the additive main effects and multiplicative interactions (AMMI) model using the founder parent Tokachi nagaha and 137 of its derived cultivars as materials. The objective was to provide a theoretical basis for effectively using germplasm in soybean breeding and production. Analysis of variance (ANOVA) showed that genotype, environment, and genotype by environment interactions were significantly different for each trait. The first three interaction principal components axes (IPCA) were highly significant, accounting for 61.28–70.00% of the total variation. The stability differed for the different traits. 50 cultivars with high general stabilities were identified. The general stability of Tokachi nagaha was moderate, as the stability coefficients (Di) of its seven traits were relatively high; this must be considered by breeders using this cultivar as a breeding parent. There were significant positive correlations between the phenotypic values and their own Di values for number of branches per plant, number of pods per plant, number of seeds per plant, and seed weight per plant. This would lead to the expectation that the phenotypic stability would be lower when a cultivar had more branches, pods, seeds, and high per plant yields. Thus, it appears difficult to breed cultivars that simultaneously have high yields and high stability

Objective Total Isotropic Sensitivity Measurement

The characterization of the performance of wireless devices plays a significant role in developing radio products that meet the demands of the latest standards and deliver a satisfying user experience. With current standard total isotropic sensitivity (TIS) measurement, the transmitters are set to work at their maximum transmission power level. However, the standard TIS test procedure is unable to accurately reflect a receiver\u27s performance because in actual usage transmitters are rarely working at their maximum power level. In measurements, different kinds of devices hold different maximum power levels. The measured radio sensitivity depends on the instantaneous local temperature of the radio, and the local temperature depends on the heat generation (power levels), the heat dissipation, and time. So the power levels and the thermal conditions could affect their radio sensitivity and, hence, the TIS. With standard TIS methods, the maximum power level and the radio\u27s thermal condition cause ambiguity in the measurements. However, this paper proposes a new objective TIS method. With this new TIS method, the measured TIS is a function of the transmitter power level at its thermally stable condition. The proposed method resolves the ambiguity of the TIS measurement

Double Exchange Interaction Between Mn3+ and Ru4+ Ions in La1-x Sr (x) Mn1-x Ru (x) O-3

To study the magnetic interaction between Mn3+ and Ru4+, we designed and synthesized a series of samples La1-x Sr (x) Mn1-x Ru (x) O-3 (0 a parts per thousand currency signx a parts per thousand currency sign 0.80), in which Mn and Ru ions remain as Mn3+ and Ru4+, respectively. The structural, magnetic, and transport properties of polycrystalline La1-x Sr (x) Mn1-x Ru (x) O-3 (0 a parts per thousand currency signx a parts per thousand currency sign 0.80) were investigated. Measurements of magnetization show that Ru4+ substitution induces and enhances ferromagnetism as xa parts per thousand currency sign 0.30. According to measurements of electronic conductivity, all doping samples show the insulating behaviors without metal-insulation transition. However, with increasing Ru4+ substitution, resistivity decreases and a shoulder appears in the rho(T) curves at around corresponding Curie temperature for 0.10 a parts per thousand currency sign x a parts per thousand currency sign 0.40. A large magnetoresistance effect is also observed in La0.60Sr0.40Mn0.60Ru0.40O3. All these phenomena is confirmed to be related with the double exchange interaction between Mn3+ and Ru4+ ions

A Comprehensive 2D-LC/MS/MS Profile of the Normal Human Urinary Metabolome

Profiling bodily fluids is crucial for monitoring and discovering metabolic markers of disease. In this study, a comprehensive analysis approach based on 1D-LC-MS/MS and 2D-LC-MS/MS was applied to profile normal human urine metabolites from 348 children and 315 adults. A total of 2357 metabolites were identified, including 1831 endogenous metabolites and 526 exogenous ones. In total, 1005 metabolites were identified in urine for the first time. The urinary metabolites were mainly involved in amino acid metabolism, small molecule biochemistry, lipid metabolism and cellular compromise. The comparison of adult’s and children’s urine metabolomes showed adults urine had more metabolites involved in immune response than children’s, but the function of binding of melatonin, which belongs to the endocrine system, showed a higher expression in children. The urine metabolites detected by the 1D-LC-MS/MS method were mainly related to amino acid metabolism and lipid metabolism, and the 2D-LC-MS/MS method not only explored metabolites from 1D-LC-MS/MS but also metabolites related to cell signaling, cell function and maintenance, etc. Our analysis comprehensively profiled and functionally annotated the metabolome of normal human urine, which would benefit the application of urinary metabolome to clinical research

Special spin behavior of rare earth ions at the A site of polycrystalline ErFe1-xCrxO3 (x = 0.1, 0.9)

Thermally induced spin control is one of the main directions for future spin devices. In this study, we synthesized single-phase polycrystalline ErFe1-xCrxO3 and combined the magnetization curves and M\"ossbauer spectra to determine the macroscopic magnetism at room temperature. The magnetization of the system at various temperatures is well simulated by molecular field theory. And it is found that under the DM interaction, not only the B-site ions undergo a reorientation process, but the spins of the A-site ions also change at the same time. The effective spin is defined as the projection of Er3+ on the Fe3+/Cr3+ spin plane, and the whole reorientation process is obtained by fitting. This study will complement the actual process of ErFe1-xCrxO3 spin reorientation and will lay a theoretical foundation for the fabrication of future spin-controlled devices