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1.
Multimedia Tools and Applications - Individual tooth segmentation and identification from cone-beam computed tomography images are preoperative prerequisites for orthodontic treatments. Instance...  相似文献   
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Hydrological drought is assessed through river flow, which depends on river runoff and water withdrawal. This study proposed a framework to project future hydrological droughts considering agricultural water withdrawal (AWW) for shared socioeconomic pathway (SSP) scenarios. The relationship between AWW and potential evapotranspiration (PET) was determined using a deep belief network (DBN) model and then applied to estimate future AWW using projections of the twelve global climate models (GCMs). 12 GCMs were bias-corrected using the quantile mapping method, climate variables were generated, and river flow was estimated using the soil and water assessment tool (SWAT) model. The standardized runoff index (SRI) was used to project the changes in hydrological drought characteristics. The results revealed a higher occurrence of severe droughts in the future. Droughts would be more frequent in the near future (2021–2060) than in the far future (2061–2100) and more severe when AWW is considered. Droughts would also be more severe for SSP5-8.5 than for SSP2-4.5. The study revealed that the increased PET due to rising temperatures is the primary cause of the increased drought frequency and severity. The AWW will accelerate the drought severities in the future in the Yeongsan River basin.

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3.
Helicobacter pylori infection is the etiology of several gastric-related diseases including gastric cancer. Cytotoxin associated gene A (CagA), vacuolating cytotoxin A (VacA) and α-subunit of urease (UreA) are three major virulence factors of H. pylori, and each of them has a distinct entry pathway and pathogenic mechanism during bacterial infection. H. pylori can shed outer membrane vesicles (OMVs). Therefore, it would be interesting to explore the production kinetics of H. pylori OMVs and its connection with the entry of key virulence factors into host cells. Here, we isolated OMVs from H. pylori 26,695 strain and characterized their properties and interaction kinetics with human gastric adenocarcinoma (AGS) cells. We found that the generation of OMVs and the presence of CagA, VacA and UreA in OMVs were a lasting event throughout different phases of bacterial growth. H. pylori OMVs entered AGS cells mainly through macropinocytosis/phagocytosis. Furthermore, CagA, VacA and UreA could enter AGS cells via OMVs and the treatment with H. pylori OMVs would cause cell death. Comparison of H. pylori 26,695 and clinical strains suggested that the production and characteristics of OMVs are not only limited to laboratory strains commonly in use, but a general phenomenon to most H. pylori strains.  相似文献   
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Effects of operating parameters in the thermal gradient chemical vapor infiltration of propane such as thermal gradient, diffusion, infiltrations time, and concentration of propane were studied by focusing on the visualizations of the intrinsic effects of these parameters. A uniform deposition in the preform was obtained with a gradually increasing temperature along the gas flow. The uniformity of deposition through the preform got improved with increasing deposition time. Results of numerical modeling estimated the experimental data very well when the pre-exponential factor of the overall rate of carbon deposition from propane reported by Vaidyaraman[1] was multiplied by 4. The average density of a preform increased by about 3 times from 0.38 to 1.15 g/cm3 after 60 hr deposition with a thermal gradient under the conditions of 3% propane in nitrogen and 840 to 900 ℃.  相似文献   
6.
Sustainable production of clean water is a global challenge. While we firmly believe that membrane technologies are one of the most promising solutions to tackle the global water challenges, one must reduce their energy consumption and fouling propensity for broad sustainable applications. In addition, different membranes face various challenges in their specific applications during long-term operations. In this short review,we will summarize the recent progresses in emerging membrane technologies and system integration to advance and sustain water reuse and desalination with discussion on their challenges and perspectives.  相似文献   
7.
To fabricate new smart materials that can deliver both the pharmaceutically active molecules and metal nanoparticles, we have formulated chitosan-based semi-IPN hydrogels and their silver nanocomposites (Ag NCs) along with amoxicillin (AMX). Semi-IPN hydrogels and their Ag NCs were synthesized from chitosan, dimethylamino ethyl methacrylate and 2-hydroxyethyl methacrylate via simple-free radical polymerization method and reducing with NaBH4. The resultant formulations were evaluated for in vitro release of AMX, anti-bacterial studies and DNA cleavage studies. The hydrogels with AMX-derived silver nanoparticles (Ag NPs) show better ability to cleave DNA and anti-microbial activity than individual AMX and Ag NPs.  相似文献   
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Betacyanins have gained increasing interest as natural food dye because of their health-promoting effects. This study investigated the betacyanins extraction from peel and flesh of red–purple pitaya using ethanol/K2HPO4-based liquid biphasic partitioning system (LBPS) by optimised concentrations of ethanol, K2HPO4, NaCl and crude. Overall, the highest values of betacyanins concentration in alcohol-rich top phase (Ct), phase volume ratio (Vr) and partition coefficient (K) of betacyanins that represented an optimum betacyanins extraction from the peel (98.080%, 1.667 and 51.097, respectively) and flesh (96.256%, 2.167 and 25.764, respectively) were achieved. Lastly, conventional solvent extractions, colour characterisation and antioxidant activity evaluation were conducted.  相似文献   
10.
Control charts for monitoring the coefficient of variation (γ) are useful for processes with an inconsistent mean (μ) and a standard deviation (σ) which changes with μ, by monitoring the consistency in the ratio σ over μ. The synthetic-γ chart is one of the charts proposed to monitor γ, and its attractiveness lie in waiting until a second point to fall outside the control limits before a decision is made. However, existing synthetic-γ charts do not differentiate between the points falling outside the upper control limit (UCL) and lower control limit (LCL). Hence, this paper proposes a side-sensitive synthetic-γ chart, where successive nonconforming samples must either fall above the UCL or below the LCL. Formulae to compute the average run length (ARL), the standard deviation of the run length (SDRL) and expected average run length (EARL) are derived using the Markov chain approach, and the algorithms to obtain the optimal charting parameters are proposed. Subsequently, the optimal charting parameters, ARL, SDRL and EARL values for various numerical examples are shown. Comparisons show that the side-sensitive synthetic-γ chart consistently outperforms the existing synthetic-γ chart, especially for small shifts. The proposed chart also consistently outperforms the Shewhart-γ chart, while showing comparable or better performance than the Exponentially Weighted Moving Average (EWMA) chart for most shift sizes, except for very small shifts. Finally, this paper shows the implementation of the proposed chart on an industrial example.  相似文献   
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