The synergism effect of total ionizing dose（TID） on a single event transient（SET） in a bipolar comparator is investigated. Experimental results show that the shapes of the SET are considerably influenced by the TI...The synergism effect of total ionizing dose（TID） on a single event transient（SET） in a bipolar comparator is investigated. Experimental results show that the shapes of the SET are considerably influenced by the TID accumulated in low dose rates. The variation tendency of SET shapes can be accurately simulated by temperature switching irradiation. The mechanism of this synergism effect is also analyzed in brief via the operating schematic of a comparator. After the accumulation of 100 krad（Si）, the lower tendency of negative SET can be attributed to the degeneration of . The change tendency of a positive SET, either lower or higher, is dependent on the load condition that limits the output range of the comparator.展开更多
We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight deg...We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles.During heavy ion irradiation,the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by 60Co gamma rays before.This could be attributed to more charges trapped caused by 60Co gamma rays,which make GaN devices more vulnerable to SEB.Moreover,the electrical parameters of GaN devices after 60Co gamma and heavy-ion irradiations are presented,such as the output characteristic curve,effective threshold voltages,and leakage current of drain.These results demonstrate that the synergistic effect of TID on SEB for GaN power devices does in fact exist.展开更多
BACKGROUND Sulfonylurea(SU)is a commonly used antidiabetic drugs effective for type 2diabetes mellitus.Previous studies have reported that the SU treatment could alter the serum free fatty acid(FFA)concentration in di...BACKGROUND Sulfonylurea(SU)is a commonly used antidiabetic drugs effective for type 2diabetes mellitus.Previous studies have reported that the SU treatment could alter the serum free fatty acid(FFA)concentration in diabetic patients;however,their exact effects remain unknown.AIM To assess the impact of SU on the FFA level in diabetic patients.METHODS A systematic literature search was conducted by consulting the PubMed,EMBASE,Cochrane Library,Reference Citation Analysis(https://www.referencecitationanalysis.com/),and Web of Science databases from January 1,1991 to July 30,2021.Either a fixed-effects model or random-effects model was applied to study the association between SU treatment and FFA concentration according to the heterogeneity test.Two investigators independently performed data extraction.The mean difference(MD)and corresponding 95%confidence interval(CI)were used to measure effect size.R3.5.1 software was utilized for conducting statistical analyses.RESULTS A total of 13 studies with 2273 individuals were selected.Results indicated that FFA concentration increased slightly after treatment with SU(MD=0.08,95%CI:0.03-0.12,P<0.01).In addition,we found that SU treatment combined with other antidiabetics could also increase the concentration of serum FFA(MD=0.14,95%CI:0.01-0.28,P<0.01).Regarding the type of SU,there was no significant difference in FFA concentration with glimepiride or glibenclamide.FFA concentration was higher at≥12 wk(MD=0.09,95%CI:0.04-0.13)but not at<12 wk(MD=0.01,95%CI:-0.07-0.09).CONCLUSION SU treatment could increase the serum FFA concentration in diabetic patients.The fundamental underlying mechanism still needs further investigation.展开更多
Background:Excessive proliferation and migration of vascular smooth muscle cells(VSMCs)are the main causes of restenosis(RS)in diabetic lower extremity arterial disease(LEAD).However,the relevant pathogenic mechanisms...Background:Excessive proliferation and migration of vascular smooth muscle cells(VSMCs)are the main causes of restenosis(RS)in diabetic lower extremity arterial disease(LEAD).However,the relevant pathogenic mechanisms are poorly understood.Methods:In this study,we introduced a“two-step injury protocol”rat RS model,which started with the induction of atherosclerosis(AS)and was followed by percutaneous transluminal angioplasty(PTA).Hematoxylin-eosin(HE)staining and immunohistochemistry staining were used to verify the form of RS.Two-step transfection was performed,with the first transfection of Lin28a followed by a second transfection of let-7c and let-7g,to explore the possible mechanism by which Lin28a exerted effects.5-ethynyl-2΄-deoxyuridine(EdU)and Transwell assay were performed to evaluate the ability of proliferation and migration of VSMCs.Western blotting and quantitative real-time polymerase chain reaction(qRT-PCR)were performed to detect the expression of Lin28a protein and let-7 family members.Results:Using a combination of in vitro and in vivo experiments,we discovered that let-7c,let-7g,and microRNA98(miR98)were downstream targets of Lin28a.More importantly,decreased expression of let-7c/let-7g increased Lin28a,leading to further inhibition of let-7c/let-7g.We also found an increased level of let-7d in the RS pathological condition,suggesting that it may function as a protective regulator of the Lin28a/let-7 loop by inhibiting the proliferation and migration of VSMCs.Conclusion:These findings indicated the presence of a double-negative feedback loop consisting of Lin28a and let-7c/let-7g,which may be responsible for the vicious behavior of VSMCs in RS.展开更多
We investigate normalized solutions to a class of Chern-Simons-Schrödinger systems with combined nonlinearities f(u)=|u|p−2u+µ|u|q−2u in R2,whereµ∈{±1}and 2<p,q<∞.The solutions correspond t...We investigate normalized solutions to a class of Chern-Simons-Schrödinger systems with combined nonlinearities f(u)=|u|p−2u+µ|u|q−2u in R2,whereµ∈{±1}and 2<p,q<∞.The solutions correspond to critical points of the underlying energy functional subject to the L2-norm constraint,namely,∫R2|u|2dx=c for c>0 given.Of particular interest is the competing and double L2-supercritical case,i.e.,µ=−1 and min{p,q}>4.We prove several existence and multiplicity results depending on the size of the exponents p and q.It is worth emphasizing that some of them are also new even in the study of the Schrödinger equations.In addition,the asymptotic behavior of the solutions and the associated Lagrange multipliersλas c→0 is described.展开更多
Twenty-one protostane-type triterpenoids with diverse structures, including nine new compounds(1 e9), were isolated from the of Alisma plantago-aquatica Linn. Structurally, alisolides A-F(1 e6), composed of an oxole g...Twenty-one protostane-type triterpenoids with diverse structures, including nine new compounds(1 e9), were isolated from the of Alisma plantago-aquatica Linn. Structurally, alisolides A-F(1 e6), composed of an oxole group coupled to a five-membered ring, represent unusual C-17 spirost protostane-type triterpenoids. Alisolide H(8) is a novel triterpenoid with an unreported endoperoxide bridge. Alisolide I(9) represents the first example of 23,24-acetal triterpenoid. Their structures were elucidated based on spectroscopic analysis, wherein the absolute configurations of 4-6, 8 were further confirmed by the Mo2(OAc)4-induced ECD method. Furthermore, all isolates were evaluated for their inhibitory effects on LPS-induced NO production in Caco-2 cells, and all the compounds showed remarkable inhibitory activities, with IC50 values in the range of 0.76 e38.20 mmol/L.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos U1532261 and U1630141
文摘The synergism effect of total ionizing dose（TID） on a single event transient（SET） in a bipolar comparator is investigated. Experimental results show that the shapes of the SET are considerably influenced by the TID accumulated in low dose rates. The variation tendency of SET shapes can be accurately simulated by temperature switching irradiation. The mechanism of this synergism effect is also analyzed in brief via the operating schematic of a comparator. After the accumulation of 100 krad（Si）, the lower tendency of negative SET can be attributed to the degeneration of . The change tendency of a positive SET, either lower or higher, is dependent on the load condition that limits the output range of the comparator.
基金Supported by the National Natural Science Foundation of China under Grant Nos. U1532261,U1630141,and 61534008the West Light Foundation of Chinese Academy of Sciences under Grant No. 2018-XBQNXZ-B-003
文摘We investigate the synergism effect of total ionizing dose(TID)on single-event burnout(SEB)for commercial enhancement-mode AlGaN/GaN high-electron mobility transistors.Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles.During heavy ion irradiation,the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by 60Co gamma rays before.This could be attributed to more charges trapped caused by 60Co gamma rays,which make GaN devices more vulnerable to SEB.Moreover,the electrical parameters of GaN devices after 60Co gamma and heavy-ion irradiations are presented,such as the output characteristic curve,effective threshold voltages,and leakage current of drain.These results demonstrate that the synergistic effect of TID on SEB for GaN power devices does in fact exist.
基金Supported by National Natural Science Foundation of China,No.81570360。
文摘BACKGROUND Sulfonylurea(SU)is a commonly used antidiabetic drugs effective for type 2diabetes mellitus.Previous studies have reported that the SU treatment could alter the serum free fatty acid(FFA)concentration in diabetic patients;however,their exact effects remain unknown.AIM To assess the impact of SU on the FFA level in diabetic patients.METHODS A systematic literature search was conducted by consulting the PubMed,EMBASE,Cochrane Library,Reference Citation Analysis(https://www.referencecitationanalysis.com/),and Web of Science databases from January 1,1991 to July 30,2021.Either a fixed-effects model or random-effects model was applied to study the association between SU treatment and FFA concentration according to the heterogeneity test.Two investigators independently performed data extraction.The mean difference(MD)and corresponding 95%confidence interval(CI)were used to measure effect size.R3.5.1 software was utilized for conducting statistical analyses.RESULTS A total of 13 studies with 2273 individuals were selected.Results indicated that FFA concentration increased slightly after treatment with SU(MD=0.08,95%CI:0.03-0.12,P<0.01).In addition,we found that SU treatment combined with other antidiabetics could also increase the concentration of serum FFA(MD=0.14,95%CI:0.01-0.28,P<0.01).Regarding the type of SU,there was no significant difference in FFA concentration with glimepiride or glibenclamide.FFA concentration was higher at≥12 wk(MD=0.09,95%CI:0.04-0.13)but not at<12 wk(MD=0.01,95%CI:-0.07-0.09).CONCLUSION SU treatment could increase the serum FFA concentration in diabetic patients.The fundamental underlying mechanism still needs further investigation.
基金supported by the National Natural Science Foundation of China Grants(Nos.82100891,81670757,82270888,82170824,81770822,81800732,and 81900685)Natural Science Foundation of Shandong Province(No.ZR2017LH025)+1 种基金Shandong Provincial Medicine and Health Science and Technology Development Program(No.2017WS461)China Postdoctoral Science Foundation(No.2021M691957).
文摘Background:Excessive proliferation and migration of vascular smooth muscle cells(VSMCs)are the main causes of restenosis(RS)in diabetic lower extremity arterial disease(LEAD).However,the relevant pathogenic mechanisms are poorly understood.Methods:In this study,we introduced a“two-step injury protocol”rat RS model,which started with the induction of atherosclerosis(AS)and was followed by percutaneous transluminal angioplasty(PTA).Hematoxylin-eosin(HE)staining and immunohistochemistry staining were used to verify the form of RS.Two-step transfection was performed,with the first transfection of Lin28a followed by a second transfection of let-7c and let-7g,to explore the possible mechanism by which Lin28a exerted effects.5-ethynyl-2΄-deoxyuridine(EdU)and Transwell assay were performed to evaluate the ability of proliferation and migration of VSMCs.Western blotting and quantitative real-time polymerase chain reaction(qRT-PCR)were performed to detect the expression of Lin28a protein and let-7 family members.Results:Using a combination of in vitro and in vivo experiments,we discovered that let-7c,let-7g,and microRNA98(miR98)were downstream targets of Lin28a.More importantly,decreased expression of let-7c/let-7g increased Lin28a,leading to further inhibition of let-7c/let-7g.We also found an increased level of let-7d in the RS pathological condition,suggesting that it may function as a protective regulator of the Lin28a/let-7 loop by inhibiting the proliferation and migration of VSMCs.Conclusion:These findings indicated the presence of a double-negative feedback loop consisting of Lin28a and let-7c/let-7g,which may be responsible for the vicious behavior of VSMCs in RS.
基金supported by National Natural Science Foundation of China (Grant No.12071486)supported by National Natural Science Foundation of China (Grant No.11671236)Shandong Provincial Natural Science Foundation (Grant No. ZR2020JQ01)。
文摘We investigate normalized solutions to a class of Chern-Simons-Schrödinger systems with combined nonlinearities f(u)=|u|p−2u+µ|u|q−2u in R2,whereµ∈{±1}and 2<p,q<∞.The solutions correspond to critical points of the underlying energy functional subject to the L2-norm constraint,namely,∫R2|u|2dx=c for c>0 given.Of particular interest is the competing and double L2-supercritical case,i.e.,µ=−1 and min{p,q}>4.We prove several existence and multiplicity results depending on the size of the exponents p and q.It is worth emphasizing that some of them are also new even in the study of the Schrödinger equations.In addition,the asymptotic behavior of the solutions and the associated Lagrange multipliersλas c→0 is described.
基金The financial support from the National Standardization of Traditional Chinese Medicine Project(ZYBZH-C-SH-49,China)the National Natural Science Foundation of China(No.81530095)+1 种基金National Standardization Program for Chinese Medicine(ZYBZH-K-LN-01,China)Shanghai Committee of Science and Technology(16DZ0500800,China)are gratefully acknowledged
文摘Twenty-one protostane-type triterpenoids with diverse structures, including nine new compounds(1 e9), were isolated from the of Alisma plantago-aquatica Linn. Structurally, alisolides A-F(1 e6), composed of an oxole group coupled to a five-membered ring, represent unusual C-17 spirost protostane-type triterpenoids. Alisolide H(8) is a novel triterpenoid with an unreported endoperoxide bridge. Alisolide I(9) represents the first example of 23,24-acetal triterpenoid. Their structures were elucidated based on spectroscopic analysis, wherein the absolute configurations of 4-6, 8 were further confirmed by the Mo2(OAc)4-induced ECD method. Furthermore, all isolates were evaluated for their inhibitory effects on LPS-induced NO production in Caco-2 cells, and all the compounds showed remarkable inhibitory activities, with IC50 values in the range of 0.76 e38.20 mmol/L.
