The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor （ACDR） powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamenta...The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor （ACDR） powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour （humid air）. The simulation involves the electro-dynamics~ chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone.展开更多
Bitter melon fruit is susceptible to yellowing,softening,and rotting under room-temperature storage conditions,resulting in reduced commercial value.Nitric oxide(NO)is an important signaling molecule and plays a cruci...Bitter melon fruit is susceptible to yellowing,softening,and rotting under room-temperature storage conditions,resulting in reduced commercial value.Nitric oxide(NO)is an important signaling molecule and plays a crucial role in regulating the fruit postharvest quality.In this study,we investigated the effects of NO treatment on changes in sensory and firmness of bitter melon fruit during postharvest storage.Moreover,transcriptomic,metabolomic,and proteomic analyses were performed to elucidate the regulatory mechanisms through which No treatment delays the ripening and senescence of bitter melon fruit.Our results show that differentially expressed genes(DEGs)were involved in fruit texture(CSLE,β-Gal,and PME),plant hormone signal transduction(ACS,JAR4,and AUX28),and fruit flavor and aroma(SUS2,LOX,and GDH2).In addition,proteins differentially abundant were associated with fruit texture(PLY,PME,and PGA)and plant hormone signal transduction(PBL15,JAR1,and PYL9).Moreover,No significantly increased the abundance of key enzymes involved in the phenylpropanoid biosynthetic pathway,thus enhancing the disease resistance and alleviating softening of bitter melon fruit.Finally,differential metabolites mainly included phenolic acids,terpenoids,and flavonoids.These results provide a theoretical basis for further studies on the physiological changes associated with postharvest ripening and senescence of bitter melon fruit.展开更多
In randomized clinical trials with right-censored time-to-event outcomes,the popular log-rank test without adjusting for baseline covariates is asymptotically valid for treatment effect under simple randomization of t...In randomized clinical trials with right-censored time-to-event outcomes,the popular log-rank test without adjusting for baseline covariates is asymptotically valid for treatment effect under simple randomization of treatments but is too conservative under covariate-adaptive random-ization.The stratified log-rank test,which adjusts baseline covariates in the test procedure by stratification,is asymptotically valid regardless of what treatment randomization is applied.In the literature,however,under simple randomization there is no affirmative conclusion about whether the stratified log-rank test is asymptotically more powerful than the unstratified log-rank test.In this article we show when the stratified and unstratified log-rank tests aim for the same null hypothesis and that,under simple randomization,the stratified log-rank test is asymp-totically more powerful than the unstratified log-rank test in the region of alternative hypothesis that is specified by a Cox proportional hazards model.We also provide some discussion about why we do not have an affirmative conclusion in general.展开更多
基金performed using HPC resources from CALMIP(Grant 2011-[P1053])supported by the French Agence Nationale de la Recherche under Project ANR-12-BS09-0019-1 through REMOVAL
文摘The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor （ACDR） powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour （humid air）. The simulation involves the electro-dynamics~ chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone.
基金supported by the National Key Research and Development Program of China[2022YFD2100105]Special Innovation Abiity Construction Fund of Beiing Academy of Agricultural and Forestry Sciences (20210437)Collaborative Innovation Center of Beijing Academy of Agricultural and Forestry Sciences (201915).
文摘Bitter melon fruit is susceptible to yellowing,softening,and rotting under room-temperature storage conditions,resulting in reduced commercial value.Nitric oxide(NO)is an important signaling molecule and plays a crucial role in regulating the fruit postharvest quality.In this study,we investigated the effects of NO treatment on changes in sensory and firmness of bitter melon fruit during postharvest storage.Moreover,transcriptomic,metabolomic,and proteomic analyses were performed to elucidate the regulatory mechanisms through which No treatment delays the ripening and senescence of bitter melon fruit.Our results show that differentially expressed genes(DEGs)were involved in fruit texture(CSLE,β-Gal,and PME),plant hormone signal transduction(ACS,JAR4,and AUX28),and fruit flavor and aroma(SUS2,LOX,and GDH2).In addition,proteins differentially abundant were associated with fruit texture(PLY,PME,and PGA)and plant hormone signal transduction(PBL15,JAR1,and PYL9).Moreover,No significantly increased the abundance of key enzymes involved in the phenylpropanoid biosynthetic pathway,thus enhancing the disease resistance and alleviating softening of bitter melon fruit.Finally,differential metabolites mainly included phenolic acids,terpenoids,and flavonoids.These results provide a theoretical basis for further studies on the physiological changes associated with postharvest ripening and senescence of bitter melon fruit.
文摘In randomized clinical trials with right-censored time-to-event outcomes,the popular log-rank test without adjusting for baseline covariates is asymptotically valid for treatment effect under simple randomization of treatments but is too conservative under covariate-adaptive random-ization.The stratified log-rank test,which adjusts baseline covariates in the test procedure by stratification,is asymptotically valid regardless of what treatment randomization is applied.In the literature,however,under simple randomization there is no affirmative conclusion about whether the stratified log-rank test is asymptotically more powerful than the unstratified log-rank test.In this article we show when the stratified and unstratified log-rank tests aim for the same null hypothesis and that,under simple randomization,the stratified log-rank test is asymp-totically more powerful than the unstratified log-rank test in the region of alternative hypothesis that is specified by a Cox proportional hazards model.We also provide some discussion about why we do not have an affirmative conclusion in general.
