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The oxidation rate of SiC can be greatly enhanced by pre-amorphization ion-implantation (PAI), and the PAI process has been employed to form the LOCal Oxidation of SiC (LOCOSiC) structure for device isolation in SiC integrated circuits (ICs). This work presents the study on the defect layer below the thermally grown SiO₂ and the impact of the defect layer on devices. The deep-level transient spectroscopy (DLTS) analysis reveals that the defect layer consists lots of C vacancies and Si vacancies. The leakage current of the edge-intensive N⁺/P-junction exhibits stronger temperature dependence than that of the P⁺/N-junction. This result confirms that C vacancy is an effective lifetime killer in n-type SiC, but not in p-type SiC. Although these defects increase the leakage current of the edge-intensive SiC N⁺/P-junction by 42 times at 150 °C compared with the junction with conventional chemical vapor deposited (CVD) field oxide (FOX), the leakage current is still much lower than the required off-state current of ICs. The defect layer has high resistance, and it is hard to let the SiC surface into inversion state so that the threshold voltage of the field MOSFET is higher than ±24 V.

Viral myocarditis (VMC) caused by coxsackievirus B3 (CVB3) infection is a life-threatening disease. The cardiac damage during VMC is not mainly due to the direct cytotoxic effect of the virus on cardiomyocytes but mostly involves the induction of immune responses. Integrin CD11b plays an important role in immune response, for instance, in the induction of Th17 cells. However, the role of CD11b in the pathogenesis of VMC remains largely unknown. In the present study, a mouse model of VMC was established by CVB3 infection and CD11b was knocked down in the VMC mice by transfection with siRNA-CD11b. The expression of CD11b and IL-17 in heart tissues, frequency of Th17 cells in spleen tissues and serum IL-17 levels were measured using quantitative RT-PCR, Western blot, immunohistochemistry, flow cytometry and ELISA. Results showed that CVB3 infection caused the pathological changes in heart tissues with the increases in the following indexes: expression of CD11b and IL-17 in heart tissues, frequency of Th17 cells in spleen tissues and serum IL-17 levels. The expression of CD11b was positively correlated with IL-17 expression in heart tissues. Depletion of CD11b attenuated the damage caused by CVB3 and decreased the frequency of Th17 cells in spleen tissues as well as in IL-17, IL-23 and STAT3 expression in heart tissues. In summary, our findings reveal that disruption of CD11b function reduced CVB3-induced myocarditis, suggesting that CD11b may be a novel therapeutic target for VMC.

Three novel dimeric bithiophenes, echinbithiophenedimers A-C (1-3), along with two known thiophenes, 4 and 5, were obtained from Echinops latifolius, and their structures were identified through extensive spectroscopic analysis and electronic circular dichroism calculations. Compounds 1-3 possessed new carbon skeletons; they are dimeric bithiophenes with 1 and 2 featuring an unprecedented 1,3-dioxolane ring system and 3 featuring an unusual 1,4-dioxane ring. These compounds are the first examples of bithiophene dimers furnished by different cyclic diethers. Dimeric bithiophenes 1-3 had good antifungal activities against five phytopathogenic fungi, and compound 3 showed excellent activity against Alternaria alternate and Pyricularia oryzae, with a minimal inhibitory concentration value of 8 μg/mL, which was close to or higher than that of carbendazim. Moreover, its effect on the mycelial morphology was observed by scanning electron microscopy. Compounds 1-3, which were demonstrated to be nonphototoxic thiophenes, exhibited better nematicidal activity than the commercial nematicide ethoprophos against Meloidogyne incognita. This study revealed that dimeric bithiophenes containing 1,3-dioxolane or 1,4-dioxane rings could be used as novel antifungal and nematicidal agents for controlling plant fungal and nematode pathogens.

Yu-Xin Wen,1,2,* Qiang Qu,3,4,* Wen-Ming Long,5 Yue Luo,6 Hai-Hui Zhuang,1 Xin-Qi Teng,1 Jian Qu1 1Department of Pharmacy, The Second Xiangya Hospital, Central South University; Institute of Clinical Pharmacy, Central South University, Changsha, 410011, People’s Republic of China; 2Department of Pharmacy, Lixian People’s Hospital in Hunan, Lixian, 415500, People’s Republic of China; 3Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, 410078, People’s Republic of China; 4National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410078, People’s Republic of China; 5Department of Pharmacy, Jingzhou District, Second People’s Hospital of Huaihua City, Huaihua, 418400, People’s Republic of China; 6Department of Pharmacy, The People’s Hospital of Liuyang, Liuyang, 410300, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jian QuDepartment of Pharmacy, The Second Xiangya Hospital, Central South University; Institute of Clinical Pharmacy, Central South University, No. 139 Middle Renmin Road, Changsha, 410011, People’s Republic of China, Tel +86-15973190614, Fax +86-731-85292072Email qujianstanley@csu.edu.cnPurpose: This study investigates the nephrotoxicity and efficacy assessment of polymyxin B (PMB) use in renal transplant patients.Patients and Methods: This retrospective study included adult (> 18 years of age) renal transplant patients who received PMB intravenous drip for more than 72 hours. Efficacy assessment of PMB included clinical treatment efficacy, microbiological efficacy at the end of PMB treatment, and in-hospital all-cause mortality. Nephrotoxicity of PMB was evaluated for further group comparison.Results: We enrolled 235 renal transplant patients in our study. After PMB treatment, 45 patients occurred PMB-nephrotoxicity, and the nephrotoxicity rate was 19.15%. Among them, 44 patients were RIFLE R stage, and one patient was RIFLE I stage. The dose of PMB used in patients was 40.0 (40.0– 50.0) mg q12h with a loading dose of 41.8± 9.8 mg. Multivariate logistic regression analysis showed that ICU admission, vasoactive agents, aminoglycosides, creatinine clearance rate before PMB use, and mean total hospital stay were independent risk factors of PMB-nephrotoxicity in kidney transplant patients. The clinical effective rate was 97.9%, and the microbiological clean rate was 66.7%.Conclusion: Our study demonstrated that PMB low dose regimens might achieve good efficacy and less nephrotoxicity in renal transplant patients. We should evaluate the severity of the infection and renal function of patients, avoid the combined use of other nephrotoxic drugs, and minimize the course of use to reduce the occurrence of PMB-nephrotoxicity.Keywords: polymyxin B, nephrotoxicity, renal transplant patients, adverse reactions

Deoxyribonucleic acid (DNA) methylation is an important epigenetic mark involved in diverse biological processes. Here, we report the critical function of tomato (

In this study, the performance of complementary metal–oxide–semiconductor (MOS) circuits fabricated on SiC substrates was investigated by designing several digital and analog circuits, and a unique process flow was developed to integrate n-type MOS (NMOS) and p-type MOS (PMOS) transistors with low and high threshold voltages (Vth) into a single chip. A detailed process flow with local oxidation of SiC isolation and a dual gate oxide with a compromised gate dielectric are presented. The performance of NMOS field-effect transistors (FETs) and PMOSFETs with low and high Vth were characterized in detail. Lateral MOS capacitors were also fabricated in the same chip to explore the characteristics of the gate dielectric. Several common logic gate components were fabricated and tested at elevated temperatures to demonstrate the normal function of these elements in a digital circuit. Static random-access memory (SRAM) cells were designed and optimized through simulation. Characterizations of all the circuit blocks are presented to demonstrate the capability of these circuits in harsh environments.

Germinating seeds can release diverse phytochemicals that repel, inhibit, or kill pathogens such as root-knot nematodes and seed-borne fungi. However, little is known about the composition of these phytochemicals and their effects on pathogens. In this study, we demonstrated that tomato seed exudates can attract the nematode Meloidogyne incognita using a dual-choice assay. Eighteen compounds were then isolated and identified from the exudates. Of these, esters (1-3), fatty acids (4-6), and phenolic acids (10-12) were proven to be the signaling molecules that facilitated the host-seeking process of second-stage juveniles (J2s) of nematodes, while alkaloids (17 and 18) disrupted J2s in locating their host. Furthermore, some phenolic acids and alkaloids showed antifungal effects against seed-borne fungi. In particular, ferulic acid (12) showed obvious activity against Aspergillus flavus (minimum inhibitory concentration (MIC), 32 μg/mL), while dihydrocapsaicin (17) showed noticeable activity against Fusarium oxysporum (MIC, 16 μg/mL). Overall, this study presents the first evidence that M. incognita can be attracted to or deterred by various compounds in seed exudates through identification of the structures of the compounds in the exudates and analysis of their effects on nematodes. Furthermore, some antifungal compounds were also found. The findings of this work suggest that seed exudates are new source for finding insights into the development of plant protective substances with nematocidal and antifungal effects.

Experimental studies of ventilation air methane oxidation were carried out in a thermal flow-reversal reactor and a fixed bed reactor in laboratory scale respectively. The reaction characteristics of ventilation air methane in a fixed bed reactor were investigated. The influence of the feed gas velocity and the lean methane concentration on the temperature profile in the thermal flow-reversal reactor was studied. The internal temperature uniformity of the cross section and the cavity of the flow-reversal reactor which have influence on lean methane conversion have also been discussed and analyzed. The results shows that the oxidation of lean methane needs to meet the ignition temperature condition and the residence time condition, and the temperature distribution in the thermal flow-reversal reactor is mainly related to the methane concentration and the feed gas velocity while the methane conversion rate is mainly related to the temperature and the residence time in the high temperature zone of the reactor.

The spatial characteristics of larval galleries and mining behaviour of the coffee stem-borer, Acalolepta cervinus (Hope), were studied on their host plant, Coffea arabica L. Results showed that entry holes were centrally located on stems of 4*!cm diameter. Older larvae than third instar preferred tunnelling upward on the stems when diameter at the entry hole is larger than 4*!cm, but downward on less than 4*!cm. The vertical distribution of entry holes skewed toward lower position of stems. The larvae preferred drilling holes beside protrusions, especially beside the bases of adjacent branches. More entry holes were located on the south-facing side of stems. Larvae boring hole on stem exhibited a strong location preference. This study helps us to understand larval tunnelling behaviour and to develop the control methods against the target pest.