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Chronic kidney disease (CKD) is the 16th leading cause of mortality worldwide. Clinical studies have raised that long-term use of omeprazole (OME) is associated with the morbidity of CKD. OME is commonly used in clinical practice to treat peptic ulcers and gastroesophageal reflux disease. However, the mechanism underlying renal failure following OME treatment remains mostly unknown and the rodent model of OME-induced CKD is yet to be established. We described the process of renal injury after exposure to OME in mice; the early renal injury markers were increased in renal tubular epithelial cells (RTECs). And after long-term OME treatment, the OME-induced CKD mice model was established. Herein, aryl hydrocarbon receptor (AHR) translocation appeared after exposure to OME in HK-2 cells. Then for both in vivo and in vitro, we found that Ahr-knockout (KO) and AHR small interfering RNA (siRNA) substantially alleviated the OME-induced renal function impairment and tubular cell damage. Furthermore, our data demonstrate that antagonists of AHR and CYP1A1 could attenuate OME-induced tubular cell impairment in HK-2 cells. Taken together, these data indicate that OME induces CKD through the activation of the AHR-CYP axis in RTECs. Our findings suggest that blocking the AHR-CYP1A1 pathway acts as a potential strategy for the treatment of CKD caused by OME. Key messages: We provide an omeprazole-induced chronic kidney disease (CKD) mice model. AHR activation and translocation process was involved in renal tubular damage and promoted the occurrence of CKD. The process of omeprazole nephrotoxicity can be ameliorated by blockade of the AHR-CYP1A1 axis. [ABSTRACT FROM AUTHOR]

Marine is the harshest corrosive environment where almost all marine underwater equipment and facilities undergo corrosion caused by marine microorganisms. With the development of marine resources globally, the marine engineering and relevant infrastructures have increased exponentially. Microbiologically influenced corrosion (MIC) leads to severe safety accidents and great economic losses. The specific aggregation of corrosive microbial communities and their interactions with materials conform to a typical ecological adaptation mechanism. On the one hand, corrosive biofilms in the marine environment selectively colonize on a specific steel substrate by utilizing their complex community composition and various extracellular polymeric substances; on the other hand, the elemental composition and surface microstructure of different engineering steels affect the microbial community and corrosive process. MIC in the marine environment is a dynamic process evolving with the formation of corrosive biofilms and corrosion products. In this mini-review, the interactions between corrosive biofilm and steel substrates are explored and discussed, especially those conducted in situ in the marine environment. Herein, the important role of iron in the dynamic process of marine corrosion is highlighted. [ABSTRACT FROM AUTHOR]

In this paper, a SiC MOSFETs gate driver for parallel connections is proposed and implemented. The proposed design enhances the reliability of parallel-connected SiC MOSFETs in high-frequency applications. High-speed over-current protections are applied for both over-voltage and under-voltage situations. In addition, a dynamic balancing current sharing scheme for SiC MOSFETs is proposed for high-speed parallel applications by current feedback and switching delay time compensation. With the proposed design, parallel-connected SiC MOSFETs can work at an operation frequency of 1 MHz with over-current protections. In addition, with the dynamic current balancing scheme, the operation temperature decreases from 115 to 86.9 °C, while the temperature difference for paralleled devices drops from 25.8 to 1.8 °C. [ABSTRACT FROM AUTHOR]

Biogenic methane in shallow shale reservoirs has been proven to contribute to economic recovery of unconventional natural gas. However, whether the microbes inhabiting the deeper shale reservoirs at an average depth of 4.1 km and even co-occurring with sulfate-reducing prokaryote (SRP) have the potential to produce biomethane is still unclear. Stable isotopic technique with culture-dependent and independent approaches were employed to investigate the microbial and functional diversity related to methanogenic pathways and explore the relationship between SRP and methanogens in the shales in the Sichuan Basin, China. Although stable isotopic ratios of the gas implied a thermogenic origin for methane, the decreased trend of stable carbon and hydrogen isotope value provided clues for increasing microbial activities along with sustained gas production in these wells. These deep shale-gas wells harbored high abundance of methanogens (17.2%) with ability of utilizing various substrates for methanogenesis, which co-existed with SRP (6.7%). All genes required for performing methylotrophic, hydrogenotrophic and acetoclastic methanogenesis were present. Methane production experiments of produced water, with and without additional available substrates for methanogens, further confirmed biomethane production via all three methanogenic pathways. Statistical analysis and incubation tests revealed the partnership between SRP and methanogens under in situ sulfate concentration (~ 9 mg/L). These results suggest that biomethane could be produced with more flexible stimulation strategies for unconventional natural gas recovery even at the higher depths and at the presence of SRP. [ABSTRACT FROM AUTHOR]

The incremental learning methods based on rough set theory are effective in acquiring knowledge in dynamically changing information tables. In this paper, we focus on the effective acquisition of decision rules by incrementally updating approximations when an incomplete information table changes. First of all, we present a four-step model to obtain three-way decision rules in an incomplete information table based on the graded tolerance relation. The first step presents the graded tolerance relation between objects. The second step calculates the degrees of objects belonging to approximations by using fuzzy logic operators. Besides, we propose a relation matrix to calculate the degrees efficiently. The third step gets three-way approximations by applying a pair of thresholds to the degrees. The fourth step obtains three-way decision rules based on the descriptions of objects. According to the four-step model, we find the notion of approximations plays an essential role in rule acquisition. Incrementally updating approximations are an effective method to obtain decision rules when an incomplete information changes. Accordingly, we study the incrementally updating approximations by incrementally updating the relation matrix when changing attributes, objects, and the attribute value of an object. Finally, experimental results illustrate that the incremental methods are more effective than non-incremental methods. [ABSTRACT FROM AUTHOR]

In this paper, a novel modulation method is proposed for the torque ripple suppression of a brushless DC motor (BLDCM) during both the commutation period and the speed regulation period. The main sources of torque ripple are the imbalance current during commutation and the PWM during speed regulation. A single-inductor multiple-output (SIMO) Buck DC–DC converter is adopted to generate input voltage for the inverter driver of a BLDCM. During the commutation period, the input voltage of an inverter can be adjusted to four times the back electromotive force (EMF), which suppresses the torque ripple caused by imbalance commutation current. Meanwhile, by changing the output voltage of a SIMO DC–DC, the speed of a BLDCM can be regulated without PWM on the inverter switches, which also suppresses the torque ripple. A control algorithm is applied on a Field Programmable Gate Array (FPGA), and the proposed BLDCM drive prototype is fabricated and tested. Measurement results show that with the proposed speed regulation strategy, the torque ripple is suppressed from 33.3% to 20.1%, and that with the proposed suppression strategy in commutation, the torque ripple is suppressed further to 5.3%. [ABSTRACT FROM AUTHOR]

Here, we report a composite photocatalyst BiOCO/BiWO which was successfully prepared via a two-step hydrothermal method assisted by Ag nanoparticles. The use of Ag nanoparticles is promoting the production of BiOCO by oxidizing ethylene glycol and to obtain the most suitable heterogenous structure. The synthesized BiOCO/BiWO photocatalyst possesses larger specific surface areas than pure BiO and pure BiWO samples. The complex structure of BiOCO/BiWO benefits the separation of photogenerated electrons and holes since its photoluminescence intensity of emission peaks were dramatically weakened. With larger specific surface areas and lower photogenerated electron-hole pairs recombination rate, BiOCO/BiWO-3% composite exhibits the highest photocatalytic activity among all samples when photodegrading gaseous pollution under visible light (λ > 420 nm). The photocatalytic activity of BiOCO/BiWO-3% composite was 2.05, 3.41 and 10.19 times than that of BiOCO/BiWO, pure BiO and pure BiWO, respectively. Finally, a possible charge separation mechanism was proposed to explain the improved photocatalytic activity of BiOCO/BiWO composite. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Background: There is a lack of existing literature regarding the quality of esophagogastroduodenoscopy (EGD) reporting for gastric cancer evaluation. This study aims to determine criteria for quality endoscopic evaluation of gastric cancer in North America by identifying important features of the EGD report for pre-operative evaluation of gastric cancer and assessing inclusion of these features in existing reports. Methods: Semi-structured interviews were conducted with experienced endoscopists from community and academic hospitals affiliated with the University of Toronto to identify essential elements for an EGD report. Then, 225 EGD reports from 2005 to 2008 were evaluated by two trained reviewers for inclusion of recommended EGD report elements and global assessment of report quality and adequacy for surgical planning. Results: Essential elements recommended by interviewed endoscopists include tumor size, location, and distance from gastroesophageal junction (GEJ). Approximately 95 % of all reports documented the location of lesions, <5 % documented distance from the GEJ, and <15 % documented tumor size. Overall report quality was rated as excellent for 4-5 % of reports; 20-42 % of all reports were deemed to be adequate for surgical planning. All surgeons interviewed as part of the endoscopist panel indicated that they would repeat the EGD before consulting with patients regarding surgical planning. Conclusions: For pre-operative evaluation of gastric cancer, tumor size, location, and distance from key anatomical landmarks were proposed as essential elements of a quality EGD report. Most of the reviewed reports did not document these elements. Report quality is perceived to be poor and may lead to repeat endoscopy. Developing a standardized EGD reporting format based on inclusion of individual parameters can improve the quality of gastric cancer management. [ABSTRACT FROM AUTHOR]