SRAM-based FPGA devices are irradiated by ^（60）Coγrays at various aose rates 10 investigate total dose effects and the evaluation method.The dependences of typical electrical parameters such as static power current...SRAM-based FPGA devices are irradiated by ^（60）Coγrays at various aose rates 10 investigate total dose effects and the evaluation method.The dependences of typical electrical parameters such as static power current, peak-peak value,and delay time on total dose are discussed.The experiment results show that the static power current of the devices reduces rapidly at room temperature（25℃） and high temperature（80℃） annealing after irradiation.When the device is irradiated at a low dose rate,the delay time and peak-peak value change unobviously with an increase in the accumulated dose.In contrast,the function parameters completely fail at 2.1 kGy（Si） when the dose rate increases to 0.71 Gy（Si）/s.展开更多
Ionizing radiation presents an important solution for virus inactivation.However,its efficacy for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)inactivation and the underlying mechanisms remain unclear.Th...Ionizing radiation presents an important solution for virus inactivation.However,its efficacy for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)inactivation and the underlying mechanisms remain unclear.This study demonstrates radiosensitivity and radiation-induced biological changes in SARS-CoV-2 using 20 wild-type and mutant strains.The results show that 1.2 kGy of electron beam(E-beam)or 0.9 kGy of X-ray irradiation can eliminate 99.99%of SARS-CoV-2 particles.The Delta and various Omicron variants exhibit heightened sensitivity to radiation compared to the wild-type,showing nearly 99.99%inactivation efficiency at 1.0 and 0.8 kGy.The relationship between irradiation dose and the logarithmic reduction in virus load adheres to a dose-response model,characterized by extremely narrow windows.Spike(S)protein disruption,rather than the commonly accepted nucleic acid cleavage,is identified as the primary inactivation mechanism(triggering a conformation transition of S protein from pre-fusion to post-fusion with minimal impact on nucleic acid integrity).This study introduces the concept of targeting critical proteins in coronavirus inactivation,offering valuable insight for infectious coronavirus disease control and vaccine development.展开更多
Total ionizing dose effect induced low frequency degradations in 130nm partially depleted silicon-on-insulator （SOI） technology are studied by ^60Co γ -ray irradiation. The experimental results show that the flick...Total ionizing dose effect induced low frequency degradations in 130nm partially depleted silicon-on-insulator （SOI） technology are studied by ^60Co γ -ray irradiation. The experimental results show that the flicker noise at the front gate is not affected by the radiation since the radiation induced trapped charge in the thin gate oxide can be ignored. However, both the Lorenz spectrum noise, which is related to the linear kink effect （LKE） at the front gate, and the flicker noise at the back gate are sensitive to radiation. The radiation induced trapped charge in shallow trench isolation and the buried oxide can deplete the nearby body region and can activate the traps which reside in the depletion region. These traps act as a GR center and accelerate the consumption of the accumulated holes in the floating body. It results in the attenuation of the LKE and the increase of the Lorenz spectrum noise. Simultaneously, the radiation induced trapped charge in the buried oxide can directly lead to an enhanced flicker noise at the back gate. The trapped charge density in the buried oxide is extracted to increase from 2.21×10^18 eV^-1 cm^-3 to 3.59×10^18？eV^-1 cm^-3 after irradiation.展开更多
Steady-state radiolysis experiments were performed to investigate the γ-irradiation treatment of pentachlorophenol (PCP) in aqueous solution. The e?ect of initial concentration on the PCP degradation was also investi...Steady-state radiolysis experiments were performed to investigate the γ-irradiation treatment of pentachlorophenol (PCP) in aqueous solution. The e?ect of initial concentration on the PCP degradation was also investigated. The experimental results showed that γirradiation was able to degrade PCP in aqueous solution successfully, and the radiolytical degradation process of PCP could be described by the first-order kinetic model. When the initial concentration of PCP was 25 and 50 mg/L and the radiation dose ...展开更多
The aim of this paper is to study the changes of apoptosis and cell cycle progression in HeLa cells after the poly(ADP-ribose)polymerase(PARP)was inhibited by its inhibitor 3-aminobenzamide(3-AB)and the mechan-isms of...The aim of this paper is to study the changes of apoptosis and cell cycle progression in HeLa cells after the poly(ADP-ribose)polymerase(PARP)was inhibited by its inhibitor 3-aminobenzamide(3-AB)and the mechan-isms of PARP action on HeLa cells damaged by irra-diation.Flow cytometry(FCM)was used to examine the PARP expression and the percentage of apoptotic cells and cell cycle progression.The percentage of HeLa cells with positive expression of PARP protein 2,4,8 and 12 h after administrated with 3-AB was significantly lower than that of the control(P<0.01).The percentages of apoptotic cells in the 3-AB plus irradiation group at the time points of 2,8,12 and 24 h after 2 Gy irradiation were higher than that in the irradiation group(P<0.01 or P<0.05)and the percentage of G2 cells decreased signifi-cantly(P<0.01 or P<0.05).It indicates that 3-AB can rapidly inhibit PARP expression of HeLa cells,promote cell apoptosis and block G2 arrest induced by irradiation.展开更多
Caffeine,which specifically inhibits ATM/ATR kinases,efficiently abrogates the ionizing radiation(IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR.Mechanisms for the effect of caffeine ...Caffeine,which specifically inhibits ATM/ATR kinases,efficiently abrogates the ionizing radiation(IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR.Mechanisms for the effect of caffeine remain to be elucidated.As a target of ATM/ATR kinases,BRCA1 becomes activated and phosphorylated in response to IR.Thus,in this work,we investigated the possible role of BRCA1 in the effect of caffeine on G2 checkpoint and observed how BRCA1 phosphorylation was regulated in this process.For these purposes,the BRCA1 protein level and the phosphorylation states were analyzed by Western blotting by using an antibody against BRCA1 and phospho-specific antibodies against Ser-1423 and Ser-1524 residues in cells exposed to a combination of IR and caffeine.The results showed that caffeine down-regulated IR-induced BRCA1 expression and specifically abolished BRCA1 phosphorylation of Ser-1524,which was followed by an override of G2 arrest by caffeine.In addition,the ability of BRCA1 to transactivate p21 may be required for MCF-7 but not necessary for Hela response to caffeine.These data suggest that BRCA1 may be a potential target of caffeine.BRCA1 and its phosphorylation are most likely to be involved in the caffeine-inhibitable event upstream of G2 arrest.展开更多
The conclusion based on transmission electron microscopy,"the tightly packed ring-like nucleoid of the Deinococcus radiodurans R1 is a key to radioresistance",has instigated lots of debates.In this study,acc...The conclusion based on transmission electron microscopy,"the tightly packed ring-like nucleoid of the Deinococcus radiodurans R1 is a key to radioresistance",has instigated lots of debates.In this study,according to the previous research of PprI’s crucial role in radioresistance of D.radiodurans,we have attempted to examine and compare the nucleoid morphology differences among wild-type D.ra-diodurans R1 strain,pprI function-deficient mutant(YR1),and pprI function-complementary strains(YR1001,YR1002,and YR1004)before and after exposure to ionizing irradiation.Fluorescence mi-croscopy images indicate:(1)the majority of nucleoid structures in radioresistant strain R1 cells ex-hibit the tightly packed ring-like morphology,while the pprI function-deficient mutant YR1 cells carrying predominate ring-like structure represent high sensitivity to irradiation;(2)as an extreme radioresistant strain similar to wild-type R1,pprI completely function-complementary strain YR1001 almost displays the loose and irregular nucleoid morphologies.On the other hand,another radioresistant pprI partly function-complementary strain YR1002’s nucleiods exhibit about 60%ring-like structure;(3)a PprI C-terminal deletion strain YR1004 consisting of approximately 60%of ring-like nucleoid is very sensi-tive to radiation.Therefore,our present experiments do not support the conclusion that the ring-like nucleoid of D.radiodurans does play a key role in radioresistance.展开更多
文摘SRAM-based FPGA devices are irradiated by ^（60）Coγrays at various aose rates 10 investigate total dose effects and the evaluation method.The dependences of typical electrical parameters such as static power current, peak-peak value,and delay time on total dose are discussed.The experiment results show that the static power current of the devices reduces rapidly at room temperature（25℃） and high temperature（80℃） annealing after irradiation.When the device is irradiated at a low dose rate,the delay time and peak-peak value change unobviously with an increase in the accumulated dose.In contrast,the function parameters completely fail at 2.1 kGy（Si） when the dose rate increases to 0.71 Gy（Si）/s.
基金supported by the National Key Research and Development Program of China(2024YFC2309900 and 2021YFC2301200)the Zhejiang Plan for the Special Support for Top-notch Talents in China(2022R52029)+1 种基金the Fundamental Research Funds for the Central Universities(2022ZFJH003)the Hangzhou Global Scientific and Technological Innovation Center of Zhejiang University(KC2021ZY0B0002).
文摘Ionizing radiation presents an important solution for virus inactivation.However,its efficacy for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)inactivation and the underlying mechanisms remain unclear.This study demonstrates radiosensitivity and radiation-induced biological changes in SARS-CoV-2 using 20 wild-type and mutant strains.The results show that 1.2 kGy of electron beam(E-beam)or 0.9 kGy of X-ray irradiation can eliminate 99.99%of SARS-CoV-2 particles.The Delta and various Omicron variants exhibit heightened sensitivity to radiation compared to the wild-type,showing nearly 99.99%inactivation efficiency at 1.0 and 0.8 kGy.The relationship between irradiation dose and the logarithmic reduction in virus load adheres to a dose-response model,characterized by extremely narrow windows.Spike(S)protein disruption,rather than the commonly accepted nucleic acid cleavage,is identified as the primary inactivation mechanism(triggering a conformation transition of S protein from pre-fusion to post-fusion with minimal impact on nucleic acid integrity).This study introduces the concept of targeting critical proteins in coronavirus inactivation,offering valuable insight for infectious coronavirus disease control and vaccine development.
基金Supported by the National Postdoctoral Program for Innovative Talents under Grant No BX201600037the Science and Technology Research Project of Guangdong Province under Grant Nos 20158090901048 and 2015B090912002the Distinguished Young Scientist Program of Guangdong Province under Grant No 2015A030306002
文摘Total ionizing dose effect induced low frequency degradations in 130nm partially depleted silicon-on-insulator （SOI） technology are studied by ^60Co γ -ray irradiation. The experimental results show that the flicker noise at the front gate is not affected by the radiation since the radiation induced trapped charge in the thin gate oxide can be ignored. However, both the Lorenz spectrum noise, which is related to the linear kink effect （LKE） at the front gate, and the flicker noise at the back gate are sensitive to radiation. The radiation induced trapped charge in shallow trench isolation and the buried oxide can deplete the nearby body region and can activate the traps which reside in the depletion region. These traps act as a GR center and accelerate the consumption of the accumulated holes in the floating body. It results in the attenuation of the LKE and the increase of the Lorenz spectrum noise. Simultaneously, the radiation induced trapped charge in the buried oxide can directly lead to an enhanced flicker noise at the back gate. The trapped charge density in the buried oxide is extracted to increase from 2.21×10^18 eV^-1 cm^-3 to 3.59×10^18？eV^-1 cm^-3 after irradiation.
基金the National NaturalScience Foundation of China (No. 50678089)and the Excellent Young Teacher Program of MOE,China.
文摘Steady-state radiolysis experiments were performed to investigate the γ-irradiation treatment of pentachlorophenol (PCP) in aqueous solution. The e?ect of initial concentration on the PCP degradation was also investigated. The experimental results showed that γirradiation was able to degrade PCP in aqueous solution successfully, and the radiolytical degradation process of PCP could be described by the first-order kinetic model. When the initial concentration of PCP was 25 and 50 mg/L and the radiation dose ...
基金supported by the National Natural Science Foundation of China(Grant No.30570546).
文摘The aim of this paper is to study the changes of apoptosis and cell cycle progression in HeLa cells after the poly(ADP-ribose)polymerase(PARP)was inhibited by its inhibitor 3-aminobenzamide(3-AB)and the mechan-isms of PARP action on HeLa cells damaged by irra-diation.Flow cytometry(FCM)was used to examine the PARP expression and the percentage of apoptotic cells and cell cycle progression.The percentage of HeLa cells with positive expression of PARP protein 2,4,8 and 12 h after administrated with 3-AB was significantly lower than that of the control(P<0.01).The percentages of apoptotic cells in the 3-AB plus irradiation group at the time points of 2,8,12 and 24 h after 2 Gy irradiation were higher than that in the irradiation group(P<0.01 or P<0.05)and the percentage of G2 cells decreased signifi-cantly(P<0.01 or P<0.05).It indicates that 3-AB can rapidly inhibit PARP expression of HeLa cells,promote cell apoptosis and block G2 arrest induced by irradiation.
基金supported by the National Basic Research Program of China (Grant No. 2010CB834202)the National Natural Science Foundation of China (Grant Nos. 10835011and 10805064)+1 种基金the Scientific Technology Research Projects of Gansu Province (Grant Nos. 0806RJYA020 and 099RJYA015)Western Talent Program of Chinese Academy of Sciences (Grant No. 0860260XBO)
文摘Caffeine,which specifically inhibits ATM/ATR kinases,efficiently abrogates the ionizing radiation(IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR.Mechanisms for the effect of caffeine remain to be elucidated.As a target of ATM/ATR kinases,BRCA1 becomes activated and phosphorylated in response to IR.Thus,in this work,we investigated the possible role of BRCA1 in the effect of caffeine on G2 checkpoint and observed how BRCA1 phosphorylation was regulated in this process.For these purposes,the BRCA1 protein level and the phosphorylation states were analyzed by Western blotting by using an antibody against BRCA1 and phospho-specific antibodies against Ser-1423 and Ser-1524 residues in cells exposed to a combination of IR and caffeine.The results showed that caffeine down-regulated IR-induced BRCA1 expression and specifically abolished BRCA1 phosphorylation of Ser-1524,which was followed by an override of G2 arrest by caffeine.In addition,the ability of BRCA1 to transactivate p21 may be required for MCF-7 but not necessary for Hela response to caffeine.These data suggest that BRCA1 may be a potential target of caffeine.BRCA1 and its phosphorylation are most likely to be involved in the caffeine-inhibitable event upstream of G2 arrest.
基金Supported by the National Basic Research Program of China(Grant No.2004CB19604)the National Natural Science Foundation of China(Grant No.30330020)the National Science fund for Distinguished Young Scholars(Grant No.30425038)
文摘The conclusion based on transmission electron microscopy,"the tightly packed ring-like nucleoid of the Deinococcus radiodurans R1 is a key to radioresistance",has instigated lots of debates.In this study,according to the previous research of PprI’s crucial role in radioresistance of D.radiodurans,we have attempted to examine and compare the nucleoid morphology differences among wild-type D.ra-diodurans R1 strain,pprI function-deficient mutant(YR1),and pprI function-complementary strains(YR1001,YR1002,and YR1004)before and after exposure to ionizing irradiation.Fluorescence mi-croscopy images indicate:(1)the majority of nucleoid structures in radioresistant strain R1 cells ex-hibit the tightly packed ring-like morphology,while the pprI function-deficient mutant YR1 cells carrying predominate ring-like structure represent high sensitivity to irradiation;(2)as an extreme radioresistant strain similar to wild-type R1,pprI completely function-complementary strain YR1001 almost displays the loose and irregular nucleoid morphologies.On the other hand,another radioresistant pprI partly function-complementary strain YR1002’s nucleiods exhibit about 60%ring-like structure;(3)a PprI C-terminal deletion strain YR1004 consisting of approximately 60%of ring-like nucleoid is very sensi-tive to radiation.Therefore,our present experiments do not support the conclusion that the ring-like nucleoid of D.radiodurans does play a key role in radioresistance.
