Electrical tree degradation of MgO/epoxy resin composites at different voltage frequencies

Electrical tree degradation is one of the main causes of insulation failure in high-frequency transformers.Electrical tree degradation is studied on pure epoxy resin(EP)and MgO/EP composites at frequencies ranging from 50 Hz to 130 kHz.The results show that the tree initiation voltage of EP decreases,while the growth rate and the expansion coefficient increase with frequency.Moreover,the bubble phenomenon at high frequencies in EP composites is discussed.Combined with trap distribution character-istics within the material,the intrinsic mechanism of epoxy composites to inhibit the growth of the electrical tree at different frequencies is discussed.It can be concluded that more deep traps and blocking effect are introduced by doping nano-MgO into EP bulks,which can improve the electrical tree resistance performance of EP composites in a wide frequency range.

The BZR1-EDS1 module regulates plant growth-defense coordination

Plants have developed sophisticated strategies to coordinate growth and immunity,but our understanding of the underlying mechanism remains limited.In this study,we identified a novel molecular module that reg-ulates plant growth and defense in both compatible and incompatible infections.This module consisted of BZR1,a key transcription factor in brassinosteroid(BR)signaling,and EDS1,an essential positive regulator of plant innate immunity.We found that EDS1 interacts with BZR1 and suppresses its transcriptional activ-ities.Consistently,upregulation of EDS1 function by a virulent Pseudomonas syringae strain or salicylic acid treatment inhibited BZR1-regulated expression of BR-responsive genes and BR-promoted growth.Furthermore,we showed that the cytoplasmic fraction of BZR1 positively regulates effector-triggered im-munity(ETI)controlled by the TIR-NB-LRR protein RPS4,which is attenuated by BZR1's nuclear transloca-tion.Mechanistically,cytoplasmic BZR1 facilitated AvrRps4-triggered dissociation of EDS1 and RPS4 by binding to EDS1,thus leading to efficient activation of RPS4-controlled ETI.Notably,transgenic expression of a mutant BZR1 that accumulates exclusively in the cytoplasm improved pathogen resistance without compromising plant growth.Collectively,these results shed new light on plant growth-defense coordina-tion and reveal a previously unknown function for the cytoplasmic fraction of BZR1.The BZR1-EDS1 mod-ule may be harnessed for the simultaneous improvement of crop productivity and pathogen resistance.

Trends and regional differences in glycemic control of patients with type 2 diabetes in China, 2009–2013

To the Editor:According to the International Diabetes Federation,China has been ranked first worldwide in terms of the prevalence of diabetes among people aged 20 to 79 years.[1]As a cornerstone in the management of patients with type 2 diabetes mellitus(T2DM),the level of glycemic control has changed considerably over the past decades.A multicenter observational study in North China showed that 45.82%of patients with T2DM met the glycated hemoglobin(HbA1c)control standard in 2017.[2]With the largest population of residents with T2DM,China is also faced with significant regional discrepancies in the rates of adequate glycemic control(HbA1c<7%),ranging from 25.9%in Shaanxi province[3]to 56.1%in Jiangsu province.[4]Indeed,previous studies in China were conducted for short periods of time,in a limited number of areas,and with relatively small sample sizes.Based on the data of the China National HbA1c Surveillance System study(CNHSS),this analysis aimed to investigate temporal trends and regional variations in glycemic control in T2DM patients in China from 2009 to 2013.

Estimation of heritabilities of disease resistance to Edwardsiella tarda and genetic correlations between resistance and growth traits in Chinese tongue sole (Cynoglossus semilaevis)

Chinese tongue sole(Cynoglossus semilaevis)is an important marine flatfish which is widely cultured in coastal areas in China.Infectious bacterial diseases such as Edwardsiella tarda imposed serious threats to this species.A potential strategy to prevent this disease is to select resistance strains.The aim of the present work was to estimate the genetic variation of disease resistance to E.tarda and to evaluate the genetic correlations between resistance traits and growth traits.Three types of models were fitted by using different trait definitions(binary,continuous and categorical).After a 9-day challenge test,the overall survival was 75.4%(ranging from 6.4%to 100%in families),and at test day 6,the overall survival was 50.7%.We set test day 6 and 9 as cut-off point times respectively.The heritabilities of survival traits were ranging from 0.10 to 0.36.Considerably higher heritability values were obtained at day 6 than at day 9,regardless of which model or trait definition used(except Trait 2 in LIN).The genetic correlations between disease resistance traits and growth traits(i.e.body weight and total length)were low and not significant from zero(−0.12–0.24).There is a substantial re-ranking of families when defined resistance as categorical and continuous traits compared to binary trait.These results confirm the existence of genetic variation for resistance against E.tarda and weak genetic correlations indicate that joint genetic improvement of E.tarda resistance and growth is scarcely available.