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[Objective] The effect of antioxidase activity of sugarcane leaves treated with ethephon and 1-MCP was studied under water stress in sugarcane seedling period to provide references for identifying the influence of ethephon and 1-MCP on drought-resistance of sugarcane seedling. [Method] Antioxidase activity of sugarcane HOC 22 planted in pot was studied by spraying ethephon (200 and 300 mg/L) to sugarcane leaf and enclosed steaming by 1-MCP (1 mg/L) for 16 hours. Finally, the antioxidase activity of POD, SOD and CAT was measured at different stages. [Result] With the increasing of water stress, the antioxidase activity of POD, SOD and CAT of sugarcane treated with 200 mg/L ethephon and 1-MCP increased markedly, and the antioxidase activity of sugarcane ascended first under mild water stress and descended at last under medium or serious water stress. Using 3(X) mg/L ethephon and 1 -MCP is instrumental in improving antioxidase activity of sugarcane under conditions of water stress mildly. But it was unfavorable for improving antioxidase activity of sugarcane to treat with 300 mg/L ethephon and I-MCP under moderate and severe water stress conditions. [Conclusion]The antioxidase activity of POD, SOD and CAT of sugarcane can be improved by using 200 mg/L ethephon and I-MCP, which is beneficial for increasing drought-resistance, however 300 mg/L ethephon and I-MCP undermines the drought-resistance of sugarcane. [ABSTRACT FROM AUTHOR]

Through artificial water - controlled methods, the effects of drought stress at different growth stages on growth and development and compensatory effect after water recovery of peanut (Arachis hypogaea L. ) were studied under pool culture in water proof installations. The results indicated that the plant height, LAI (leaf area index), the dry weight of shoot and pod of peanut all decreased at various levels. With the prolongation of drought stress treatment, their decrease range amplified under drought stress at diiferent growth stage. The drought stress at pod filling and seedling stage had relatively less effect on plant growth of peanut. The compensatory effect affer water recovery was relatively greater at seedling stage. The drought stress at flower - pegging and pod - setting stage had relatively greater effects on the plant growth of peanut, and the compensatory effect after water recovery was negligible at these stages. The drought stress had the least effect on pod yield of peanut and it had increasingly greater effect at pod fiiling and mature stage, flower - pegging and pod setting stage. The effects of drought stress at seedling stage on pod yield of peanut was mainly relevant to the decrease of valid pod number. The effects of drought stress at pod - fiiling and mature stage on pod yield of peanut was mainly relevant to the decrease of pod plumpness. The effects of drought stress at flower - pegging and pod setting stage on pod yield of peanut were the combined effects of low valid pod number and low pod plumpness. [ABSTRACT FROM AUTHOR]

Objective To analyze the impact factors for unplanned discontinuation of patient-controlled intravenous analgesia (PCIA) within 24 h after thoracic surgery so as to prevent over-use of medical resources. Methods Clinical data of patients with thoracic surgery in Peking Union Medical College Hospital from April 1, 2018 to March 31, 2019 were reviewed. Patients were divided into two groups according to the duration time from the start to the end of PCIA: group A(≤24 h) and group B(＞24 h). Univariate analysis and logistic multivariate regression were used to compare the demographic characteristics, anesthesia/surgery type, PCIA regimen and adverse effect between the two groups. Results A total of 371 patients were included in this study. Univariate analysis showed that the proportion of patients stopped PCIA in 24 hours was higher in female patients than that in male patients (16.8%/39.4%). The proportion of PCIA stop in 24 hours after thoracoscopic surgery was higher than that after thoracotomy (31.4%/19.7%). In PCIA, patients who used morphine were more likely to stop using postoperative PCIA within 24 hours than those who used oxycodone and sufentanil, and patients who used oxycodone were more likely to stop using PCIA within 24 hours than those who used sufentanil (60%/40.5%/25.3%). The proportion of patients who stopped using 5-HT3 receptor blocker in PCIA within 24 hours was lower than that of those who did not (14.9%/30.6%). Patients who were of sedation at the time of follow-up were less likely to stop using PCIA within 24 hours than those who did not have sedation (25.3%/41.8%). Patients who complained of postoperative nausea were more likely to stop using PCIA within 24 hours than those who did not(62.1%/17.3%).The proportion of patients with postoperative vomiting who stopped using PCIA within 24 hours was higher than those without postoperative vomiting (64%/22.1%). Logistic multivariate analysis showed that female, thoracoscopic surgery, intraoperative inhalation of nitrous oxide, postoperative nausea and postoperative vomiting were related with unplanned discontinuation of PCIA within 24 h after thoracic surgery. Conclusions For patients undergoing thoracic surgery,the application of postoperative PCIA should be comprehensively evaluated according to the patient's personal situation, surgery type, and the risk of postoperative nausea/vomiting.

Although deep neural networks perform well in many areas,research shows that deep neural networks are vulnerable to attacks from adversarial examples.There are many algorithms for attacking neural networks,but the attack speed of most attack algorithms is slow.Therefore,the rapid generation of adversarial examples has gradually become the focus of research in the area of adversarial examples.AdvGAN is an algorithm that uses the network to attack another network,which can generate adversarial samples extremely faster than other methods.However,when carrying out a targeted attack,AdvGAN needs to train a network for each target,so the efficiency of the attack is low.In this article,we propose a multi-target attack network(MTA) based on the generative adversarial network,which can complete multi-target attacks and quickly generate adversarial examples by training only once.Experiments show that MTA has a higher success rate for targeted attacks on the CIFAR10 and MNIST datasets than AdvGAN.We have also done adversarial sample transfer experiments and attack experiments under defense.The results show that the transferability of the adversarial examples generated by MTA is stronger than other multi-target attack algorithms,and our MTA method also has a higher attack success rate under defense.