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Objectives: The aim of this study was to develop an assessment tool for automatic detection of dental caries in periapical radiographs using convolutional neural network (CNN) architecture. Methods: A novel diagnostic model named ResNet + SAM was established using numerous periapical radiographs (4278 images) annotated by medical experts to automatically detect dental caries. The performance of the model was compared to the traditional CNNs (VGG19, ResNet-50), and the dentists. The Gradient-weighted Class Activation Mapping (Grad-CAM) technique shows the region of interest in the image for the CNNs. Results: ResNet + SAM demonstrated significantly improved performance compared to the modified ResNet-50 model, with an average F1 score of 0.886 (95% CI 0.855–0.918), accuracy of 0.885 (95% CI 0.862–0.901) and AUC of 0.954 (95% CI 0.924–0.980). The comparison between the performance of the model and the dentists revealed that the model achieved higher accuracy than that of the junior dentists. With the assist of the tool, the dentists achieved superior metrics with a mean F1 score of 0.827 and the interobserver agreement for dental caries is enhanced from 0.592/0.610 to 0.706/0.723. Conclusions: According to the results obtained from the experiments, the automatic assessment tool using the ResNet + SAM model shows remarkable performance and has excellent possibilities in identifying dental caries. The use of the assessment tool in clinical practice can be of great benefit as a clinical decision-making support in dentistry and reduce the workload of dentists. [ABSTRACT FROM AUTHOR]

Several previous studies have found the deleterious effects of cadmium exposure on bone. However, studies on the effects of cadmium exposure on bone mineral density (BMD) in gender- and race-specific groups are still lacking. The aim of this study was to investigate the relationship between cadmium exposure and BMD in adults and the gender and racial differences therein. Weighted multivariate regression, generalized weighted model, and smoothed curve fitting were used to explore the relationship between lumbar BMD with blood cadmium (B-Cd) and urine cadmium (U-Cd) based on data from the National Health and Nutrition Examination Survey (NHANES). In addition, subgroup analyses were further used to investigate the differential associations across gender and race. Of the 4335 adult participants. After adjusting for primary demographic variables, B-Cd [− 0.018 (− 0.028, − 0.008)] and U-Cd [− 0.010 (− 0.020, − 0.001)] were shown to be negatively related to lumbar BMD. In the fully adjusted model, the negative association between B-Cd and lumbar BMD was maintained [− 0.010 (− 0.018, − 0.002)]. In the subgroup analysis stratified by gender and race, this relationship was retained in females and non-Hispanic blacks. Furthermore, these negative associations were most pronounced among non-Hispanic black women [B-Cd and lumbar BMD, − 0.046 (− 0.076, − 0.017); U-Cd and lumbar BMD, -0.034 (− 0.063, − 0.006)]. Our findings suggest that there are significant sex and race differences in the negative association between cadmium exposure and BMD. This negative association was most prominent in non-Hispanic black females. [ABSTRACT FROM AUTHOR]

The activation of large ancient rock landslides caused by reservoir operation is a primary threat to the TGR. Understanding the deformation characteristics and failure mechanisms of these landslides can be helpful for stability assessment and long-term landslide prediction. The primary aim of this study is to research the motion characteristics of ancient rock landslides and their relationships with engineering activities and natural factors. The Tanjiahe landslide, a large reactivated landslide in the TGR region, is used as an example. Long-term professional monitoring data collected since 2006 show that the landslide is experiencing creep deformation. By combining 15 years of meteorological, hydrological and manual GNSS monitoring information, 5 years of displacement measurements from open fractures and deep boreholes, automatic GNSS measurements, and macroscopic inspection results, the deformation mechanisms of landslides are studied in detail. The study shows that landslide deformation is affected by the reservoir water level and that rainfall promotes landslide deformation. Specifically, from November to May, during the high reservoir water level stage and subsequent declining water level stage, the landslide exhibits a very distinct movement pattern with high deformation, lasting nearly 7 months. As the water level rises, the deformation subsides until almost no deformation exists. Landslide displacement continues to increase each year, indicating likely slope instability. However, the deformation rate of the Tanjiahe landslide is gradually decreasing, and the probability of large-scale sliding is low; still, the monitoring system must be strengthened, and additional research must be performed on the corresponding deformation mechanism. [ABSTRACT FROM AUTHOR]

Vehicular platoons are among the most advanced driving assistance systems that may generate considerable fuel savings and increase traffic efficiency. However, communication between vehicles in a platoon is always vulnerable to eavesdropping due to the broadcast nature of wireless channels. To address this issue, we investigate security issues from the physical layer perspective for multi-hop vehicular platooning. The dynamic shielding secured transmission scheme is proposed to guarantee the confidential transmission of private information. Specifically, the neighboring vehicles can alternately act as friendly shielders, which transmit jamming signals to interfere with the eavesdroppers without knowing the channel state information, and thus the secrecy capacity would increase. The mathematical derivation of secrecy capacity is obtained for performance analysis. Meanwhile, the numerical results verify the properties, efficiency, and adaptability of the proposed scheme. [ABSTRACT FROM AUTHOR]

The seepage calculation of water fluctuation is the crucial precondition for landslide stability evaluation. It is controlled by the initial condition, boundary condition, and soil or rock structure as well as geotechnical parameters. Although the geotechnical parameters and boundary condition have greater influence on seepage and the stability of landslides, the role of the initial groundwater position cannot be ignored. To investigate the influence of an initial groundwater table on landslides, especially the influence of cyclical reservoir water fluctuation on their long-term stability, seven different methods to determine the initial groundwater table were proposed in the presented study, among which one is the actual groundwater table, and the other six are obtained with simplified methods. According to the results of the calculations, at the beginning, there is some difference in the factor of safety among different initial groundwater tables. The maximum value of relative tolerance reduces to less than 1.0 % 160 days later. After a filling-drawdown cycle, the relative tolerance of all methods reduces to less than 0.8 %, which could be ignored. It is also observed that, the closer the hydraulic gradient of the proposed initial groundwater table is to the actual condition, the smaller is the relative tolerance. Therefore, to study the influence of cyclical reservoir water fluctuation on landslide long-term stability, the initial groundwater table could be proposed as (1) equal to reservoir water level and (2) on a straight line with the hydraulic gradient equal to the weighted average of actual groundwater table for simplification. [ABSTRACT FROM AUTHOR]

The impulsive wave is considered as one of the most notably secondary hazards induced by landslides in reservoir areas. The impulsive wave with considerable wave amplitude is able to cause serious damage to the dam body, shoreline properties and lives. To investigate and predict the wave characteristics, many experimental studies employed the generalized channels rather than the realistic topography. Deviation from the idealized geometries may result in non-negligible effects due to the wave refraction or reflection with complex topography. To consider the topography effect, a prototype scaled experiment was conducted. A series of tests with different collocation of parameters were performed. The experimental results were then summarized to propose empirical equations to predict the maximum wave amplitude, and wave decay in channel direction. The generalized empirical equations can obtain better results for wave features prediction by compared with those derived from the idealized models. Furthermore, a 3D numerical modeling corresponding to the physical experiment was conducted based on the SPH method. The wave characteristics in the sliding and channel directions were investigated in detail including the maximum wave amplitude, wave run-up, wave arrival time and wave crest amplitude decay. The comparison between the simulation and experiment indicates the promising accuracy of the SPH simulation in determining the general features even with complex river topography. Finally, the limitation and applicability of both the experimental and numerical methods in analyzing the practical engineering problems were discussed. Combination of the both methods can benefit the hazard prevention and reduction for landslide generated impulsive waves in reservoir area. [ABSTRACT FROM AUTHOR]

Previously, we have shown that synuclein γ (SNCG), a member of the brain protein synuclein family, is highly expressed in human infiltrating breast carcinomas but not expressed in normal or benign breast tissues. The SNCG mRNA was also detected in several human breast cancer cell lines with the highest expression found in H3922, a cell line derived from an infiltrating ductal carcinoma. In this study, we show that expression of SNCG mRNA in H3922 cells is significantly decreased by treating cells with the cytokine oncostatin M (OM) who has a growth-inhibitory effect on these cells. A decrease in SNCG mRNA level can be detected as early as 30 min after OM addition. By 4 h OM treatment, the level of SNCG mRNA was decreased to 70% of control, and by 24 h the mRNA was below detectable level. Western blot analysis further demonstrated the suppression of SNCG protein expression by OM. The level of SNCG protein in H3922 cells was reduced more than 90% by OM after 2 days. Since OM- induced growth inhibition occurs after 3–4 days, the down-regulation of SNCG expression appears to proceed the effect of OM on cell growth. Additional experiments to measure the transcriptional rates of SNCG indicate that the observed OM-induced down-regulation of SNCG mRNA occurs mainly at the transcriptional level. In an attempt to examine the role of SNCG gene in the proliferation of breast cancer cells, SNCG cDNA was stably transfected into MCF-7 cells that do not express endogenous SNCG gene. Examination of cell growth under anchorage-dependent and anchorage-independent conditions demonstrates that over expression of SNCG gene significantly stimulated the growth of MCF-7 cells both in monolayer culture and in soft agar. These data together suggest that SNCG may play a role in cell proliferation. [ABSTRACT FROM AUTHOR]

We recently identified, cloned, and characterized a novel human tissue inhibitor of metalloproteinases-4, TIMP-4 (Greene et al., 1996). To determine if TIMP-4 can modulate the in vivo growth of human breast cancers, we transfected a full-length TIMP-4 cDNA into MDA-MB-435 human breast cancer cells and studied the orthotopic growth of TIMP-4-transfected (TIMP4-435) versus control (neo-435) clones in the mammary fat pad of athymic nude mice. TIMP4-435 clones expressed TIMP-4 mRNA and produced anti-metalloproteinase (MMP) activity, while neo-435 clones did not express TIMP-4 mRNA or produce detectable anti-MMP activity. Overexpression of TIMP-4 inhibited the invasion potential of the cells in the in vitro invasion assay. When injected orthotopically into nude mice, TIMP-4 transfectants were significantly inhibited in tumor growth by 4 – 10-fold in primary tumor volumes; and in an axillary lymph node and lung metastasis as compared with controls. These results suggest the therapeutic potential of TIMP-4 in treating cancer malignant progression [ABSTRACT FROM AUTHOR]

The original version of this article unfortunately contained a mistake. "Southwest Minzu Nationalities" in affiliation 1 should be "Southwest Minzu University". [ABSTRACT FROM AUTHOR]

Al17 clusters exhibit apparent changes in curvature, which resemble macroscopic metal tips. Here, we show, using the density functional theory method, how surface charges of Al17q (q = −2 to +3) ions affect the adsorption and dissociation behavior of HCl molecules. Geometries, adsorption energies, vibrational frequencies, Mulliken population analysis and transition states of (Al17HCl)q (q = −2 to +3) adsorption complexes were studied. The results revealed that HCl molecules tend to locate on tip sites of the Al17q (q = −2 to +3) ions. Anionic adsorption complexes are prone to H affinity adsorption, whereas cationic adsorption complexes favor Cl-affinity adsorptions. These adsorption behaviors look quite like macroscopic tip effects. H–Cl bonds of the adsorption complexes weaken with an increase in either positive or negative charge. Dissociation barriers of the H–Cl bonds exhibit binding energies that are 2 orders of magnitude smaller than those of an isolated HCl molecule. Considering adsorption energies and dissociation barriers comprehensively, HCl molecules should dissociate spontaneously for all the models considered. Generally, the more negative charges the clusters carry, the more energy the reaction will release. [ABSTRACT FROM AUTHOR]

Studying the formation mechanisms and influencing factors of typical regional landslides is a crucial step in landslide control and disaster prediction. The mechanism of formation and the influence of hydrodynamic factors on accumulated landslides in the Three Gorges Reservoir have always been a focus of attention. Although rainfall and reservoir water level factors interact with each other, refining the impact areas and characteristics of these two factors will be beneficial for future research on accumulated landslides in the Three Gorges Reservoir area. Taking the Sanmendong landslide as an example and relying on its geological background and professional monitoring data, this study employs gray correlation analysis to analyze the sensitivity between changes in hydrodynamic factors and changes in landslide safety factor. It discusses the regions affected by rainfall and the descending speed of the reservoir water level under different conditions, as well as the changing patterns of data. The ILF-FFT landslide prediction model is utilized to study the relationship between real monitoring data of the Sanmendong landslide and fluctuations in hydrodynamic factors, obtaining the weight coefficients of hydrodynamic factors in the model and separating the fluctuation curve under the influence of rainfall and reservoir water level fluctuations. A comparative analysis of the contribution of hydrodynamic factors to the deformation of the Sanmendong landslide is conducted. The results indicate that the overall deformation of the Sanmendong landslide is more sensitive to rainfall factors, and as the descending speed of the reservoir water level increases, its sensitivity to landslide deformation will also increase. The local deformation of the landslide toe is greatly affected by the factors of reservoir water level descent, and with the increase of the descending speed of the reservoir water level, the correlation results also increase. It is important to note that there is a sudden change in the correlation results at a descending speed of 1.0 m/d in the local stability analysis, which is related to the most dangerous sliding surface identified in the simulation calculation and requires special attention during the process of reservoir water level descent. Furthermore, the deformation of the landslide toe in Sanmendong is greatly affected by the descent of the reservoir water level, while the deformation of the landslide head is more influenced by rainfall factors. [ABSTRACT FROM AUTHOR]