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Artificial Intelligence (AI) has penetrated the field of education. Trust has long been regarded as a driver for the acceptance of technology. Netnography and interviews were used to investigate trust in AI-based educational systems from the perspective of users. We identified the factors influencing trust in AI-based educational systems and categorized them as being related to technology, context and individual. Technology-related factors encompass functionality, helpfulness, interpretability, dependability and interaction interface. Context-related factors encompass benevolence of educational organizations, data management, teachers? competencies, official norms and knowledge characteristics. Individual-related factors encompass perception of the nature of learning, propensity to interact with teachers, perception of AI and autonomy orientation. The results from this paper will contribute to the literature on trust in technology and AI ethics in education.

Environmental applications require accurate air temperature (T-air) datasets with different temporal and spatial resolutions. Existing methods generally improve the estimation accuracy of T-air using environmental variables as auxiliary data to overcome problems related to sparse metrological stations. However, these data are always fixed and do not comprehensively explain the variations in T-air values at all temporal and spatial scales. Moreover, these methods seldom consider the spatial heterogeneity of relationships between T-air and auxiliary data. This heterogeneity is often caused by several factors, such as land type, topography, and climate. This study proposes an estimation method to produce maximum, minimum, and mean T-air (T-max, T-min, and T-mean) datasets at different temporal and spatial resolutions using satellite-derived digital elevation model data and both nighttime and daytime land surface temperature data as auxiliary data. The method is based on the assumption that the relationships between T-air and the chosen auxiliary data vary spatially. These relationships were further explored using geographically weighted regression with adaptive bi-square kernel function. The derived relationships were used to construct a T-air estimation model. Monthly T-air data with 5-km resolution and 8-day T-air data with 1-km resolution were produced for 2010. The results show that the proposed method can accurately represent the variations in T-air; the R-2 values were in the range of 0.95-0.99 for the monthly T-air data and 0.93-0.99 for the 8-day T-air data. The root mean square errors (RMSEs) for the monthly and 8-day T-max, T-min, and T-mean data of the year 2010 were 1.29 and 1.45 degrees C, 1.24 and 1.29 degrees C, and 0.8 and 1.2 degrees C, respectively. These results were compared with those from other estimation methods, specifically the estimation of T-air based on multiple linear regression (EATMLR) and regression kriging (EATRK). The proposed method was found to produce RMSEs that were 25-26% smaller than EATMLR and 34-42% smaller than EATRK.

To investigate the effects of multiple environmental conditions on greenhouse gas (CO2 , N2 O, CH4 ) fluxes, we transferred three soil monoliths from Masson pine forest (PF) or coniferous and broadleaved mixed forest (MF) at Jigongshan to corresponding forest type at Dinghushan. Greenhouse gas fluxes at the in situ (Jigongshan), transported and ambient (Dinghushan) soil monoliths were measured using static chambers. When the transported soil monoliths experienced the external environmental factors (temperature, precipitation and nitrogen deposition) at Dinghushan, its annual soil CO2 emissions were 54% in PF and 60% in MF higher than those from the respective in situ treatment. Annual soil N2 O emissions were 45% in PF and 44% in MF higher than those from the respective in situ treatment. There were no significant differences in annual soil CO2 or N2 O emissions between the transported and ambient treatments. However, annual CH4 uptake by the transported soil monoliths in PF or MF was not significantly different from that at the respective in situ treatment, and was significantly lower than that at the respective ambient treatment. Therefore, external environmental factors were the major drivers of soil CO2 and N2 O emissions, while soil was the dominant controller of soil CH4 uptake. We further tested the results by developing simple empirical models using the observed fluxes of CO2 and N2 O from the in situ treatment and found that the empirical models can explain about 90% for CO2 and 40% for N2 O of the observed variations at the transported treatment. Results from this study suggest that the different responses of soil CO2 , N2 O, CH4 fluxes to changes in multiple environmental conditions need to be considered in global change study.

A simple, sensitive, and rapid method for determination of L-trantinterol in rat plasma was developed for the first time by using LC coupled to MS/MS based on chiral stationary phase. A baseline separation of the enantiomers of trantinterol was achieved on a Chirobiotic V column, using a mixture of acetonitrile-methanol-ammonia-acetic acid (80:20:0.01:0.02, v/v/v/v) as the mobile phase. The detection was performed on a triple-quadrupole tandem mass spectrometer by multiple reaction monitoring mode via ESI. The calibration curve was linear in concentration range from 0.270 to 108 ng/mL in plasma with the lower limit of quantification of 0.270 ng/mL. The intra- and interday precision (relative standard deviation) values were within 10.9% and the accuracy (relative error) was from 2.6 to 9.2% at all quality control levels. The method has been successfully applied to a study of L-trantinterol pharmacokinetics in rats.

The spatial scale effect on sediment concentration in runoff has received little attention despite numerous studies on sediment yield or sediment delivery ratio in the context of multiple spatial scales. We have addressed this issue for hilly areas of the Loess Plateau, north China where fluvial processes are mainly dominated by hyperconcentrated flows. The data on 717 flow events observed at 17 gauging stations and two runoff experimental plots, all located in the 3906km(2) Dalihe watershed, are presented. The combination of the downstream scour of hyperconcentrated flows and the downstream dilution, which is mainly caused by the base flow and is strengthened as a result of the strong patchy storms, determines the spatial change of sediment concentration in runoff during flood events. At the watershed scale, the scouring effect takes predominance first but is subordinate to the downstream dilution with a further increase in spatial scale. As a result, the event mean sediment concentration first increases following a power function with drainage basin area and then declines at the drainage basin area of about 700 km(2). The power function in combination with the proportional model of the runoff-sediment yield relationship we proposed before was used to establish the sediment-yield model, which is neither the physical-based model nor the regression model. This model, with only two variables (runoff depth and drainage basin area) and two parameters, can provide fairly accurate prediction of event sediment yield with model efficiency over 0.95 if small events with runoff depth lower than 1 mm are excluded. Copyright (c) 2011 John Wiley & Sons, Ltd.

The tumor suppressor p53 regulates the expression of various genes that promote apoptosis. PIG11 (P53-induced gene 11), also referred to as TP53I11 (tumor protein p53 inducible protein 11), is a direct p53 target gene. Recent data demonstrated that PIG11 was up-regulated markedly in arsenic trioxide induced apoptosis by DDRT-PCR, suggesting a new class of p53 target genes that sensitize cells to the effects of chemotherapeutic agents. In this study, through the construction of a recombinant GFP-PIG11 expression vector and transfection of HEK293 cells with GFP or GFP-PIG11, the role of PIG11 in apoptosis was analyzed. Results demonstrated that the percentage (11.38%) of apoptotic cells with GFP-PIG11 transfection was higher than that (7.28%) of with only GFP transfection (P0.05). At 24 h after 1 microM of arsenic trioxide treatment, apoptotic cells exhibited a significant increase in the expression of GFP-PIG11 (36.67%+/-2.78), in contrast, 10.50%+/-2.03 only GFP and 5.25%+/-0.96 vehicle control (P0.01). In addition, we showed that intracellular content of reactive oxygen species (ROS) was 9.66+/-0.52 in GFP-PIG11 transfection, higher than 5.21+/-0.08 in GFP only and 5.99+/-0.45 in vehicle control (P0.01). The above results suggest that overexpression of PIG11 could induce cell apoptosis in the low levels and enhanced the apoptotic effects of arsenic trioxide. The process could be involved in intracellular generation of ROS.

In this paper, tapping mode atomic force microscopy was applied to visualize the higher order chromatin structure reconstituted from calf thymus DNA and calf thymus whole histone in vitro. All the revealed reconstituted chromatin structures consisted of similar well-defined subunits. In some of the chromatin structures, four to six subunits per turn were wrapped right-handed to form a flattened solenoid with a height distribution of 12 ± 2 nm; and the other Y- and V-shaped chromatin structures were formed by aggregation of these solenoids, which presented similar heights as the solenoids. Typical atomic force microscopy (AFM) images revealed relatively regular solenoid structure (containing six nucleosomes per turn) with a ratio of diameter to pitch of 3 : 1, which is in good agreement with that of 30 : 11 in the chromatin solenoid model proposed by Finch and Klug. Bio-gel elution was used to separate reconstituted chromatin from uncombined histone particles, which proved to be helpful for the AFM imaging of the higher order chromatin structure with nearly no disturbance of histone particles and salt in the background. The AFM observations showed that the higher order chromatin structure was preserved well enough during the bio-gel elution process. The cause for the stability of higher order chromatin structure during the bio-gel elution was analysed. Electron microscopy analysis and circular dichroism spectroscopy investigation of the DNA–histone complexes indicated the formation of ordered aggregates. Copyright © 2001 John Wiley & Sons, Ltd.

Atomic force microscopy was used to investigate the local ordering characteristics of hypotonic spread HeLa nucleosomal chains. Nucleosomal chains were diluted in tridistilled water and dropped on freshly cleaved mica, rinsed with ultrapure water and air dried. We have found that nucleosomal chains show varied structures in vitro: beads-on- a-string irregular arrangement, open rings, closed rings. Neither the hydrolysation of trypsin nor the digestion of micrococcal nuclease or nuclease is necessary for observation of 'beads-on-a-string'. The closed rings formed by a nucleosomal chain have a close relevance to the two marked characteristics of the mild method developed in this work for preparing H1-depleted chromatin. The described method may provide a new reliable way to study the behaviour of the extended chromatin fibre at low ionic strength. These observations may provide a useful clue to elucidate how the structure of the extended chromatin fibre affects DNA transcription, replication and repair.

Telomeres are an essential nucleoprotein structure at the ends of all eukaryotic chromosomes. Studies on the structure and function of telomeres have received particular attention owing to their possible significance to ageing and cancer. In this work, human telomere from HeLa cells were isolated and purification by bio-gel P-2 column. Large duplex loops with a tail were first observed directly in the purified telomeric DNA species by atomic force microscopy (AFM). The lengths of the loop and tail are ∼2.5 ± 0.5 and 2.0 ± 1.5 kb, respectively. The AFM images also showed that the circular portion of loops is assumed to be a double-stranded structure according to its apparent height, but to be a triplex or tetraplex structure for the loop-tail junction. These results indicate that telomeres in human cells may end in large loops, which is an advantage in further studies on the structure and function of telomeres in cells and provides a new procedure for the study of telomere structure.