Objective To observe the effects of signal factors of corticosterone (CS), cAMP, cGMP, Ca^2+ and protein kinase C (PKC) on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA ...Objective To observe the effects of signal factors of corticosterone (CS), cAMP, cGMP, Ca^2+ and protein kinase C (PKC) on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA lyric rate for thymocytes was measured by fluomspectrophotometry. Results The DNA lyric rate for thymocytes 4-8 hours after irradiation with 2-8 Gy was significantly higher than that in the control (P〈0.01). As compared with the control, the DNA lyric rate for thymocytes treated with 0.01 μnol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.05-0.4 μg/mL ionomycin (Iono, P〈0.05 or P〈0.01) or 0.05-0.4 ng/mL phorbol myristate acetate (PMA, P〈0.05 or P〈0.01), respectively, was significantly increased, while the rate for thymocytes treated with 50 ng/mL cGMP was not significantly increased. The DNA lyric rate for thymocytes treated with 0.01 μmol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.2 and 0.4 μg/mL Iono (P〈0.05), and 0.2 and 0.4 ng/mL PMA (P〈0.05) plus 4-Gy irradiation, respectively, was significantly higher than that treated with single 4-Gy irradiation, while the rate for thymocytes treated with 50 ng/mL cGMP plus 4-Gy irradiation was not increased. When both 0.4 I.tg/mL Iono and 0.4 ng/mL PMA acted on the thymocytes, the DNA lyric rate for thymocytes was significantly higher than that in the control (P〈0.01), the DNA lytic rate for thymocytes treated with both 0.4 μg/mL Iono and 0.4 ng/mL PMA plus 4-Gy irradiation was significantly higher than that treated with single 4-Gy irradiation (P〈0.05), but was Iono plus 4-Gy irradiation or 0.4 ng/mL PMA plus 4-Gy irradiation. can promote thymocyte apoptosis induced by larger dose X-rays. not significantly higher than that treated with 0.4 μg/mL Conclusion CS, cAMP, Ca^2+, and PKC signal factors can promote thymocyte apoptosis induced by larger dose X-rays.展开更多
Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of ...Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of laser pulse and the overall shape of the intensity distribution in the focal line have different influences on the plasma. Calculations show that the evolution of temperature variation is more sensitive to the pulse duration and the electron density variation is more sensitive to the pulse intensity. Pulses with duration of 200 ps to 500 ps and with intensity of 0.2 TW/cm2 to 1.0 TW/cm2 are proved acceptable in slab x-ray lasers.展开更多
X-irradiation has a beneficial effect in treating spinal cord injury. We supposed that X-irradiation could improve the microenvironment at the site of a spinal cord injury and inhibit glial scar formation. Thus, this ...X-irradiation has a beneficial effect in treating spinal cord injury. We supposed that X-irradiation could improve the microenvironment at the site of a spinal cord injury and inhibit glial scar formation. Thus, this study was designed to observe the effects of 8 Gy X-irradiation on the injury site at 6 hours and 2, 4, 7, and 14 days post injury, in terms of improvement in the microenvironment and hind limb motor function. Immunohistochemistry showed that the expression of macrophage marker ED-1 and the area with glial scar formation were reduced. In addition, the Basso, Beattie and Bresnahan score was higher at 7 days post injury relative to the other time points post injury. Results indicated that X-irradiation at a dose of 8 Gy can inhibit glial scar formation and alleviate the inflammatory reaction, thereby repairing spinal cord injury. X-irradiation at 7 days post spinal cord injury may be the best time window.展开更多
Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have bee n widely studied.However,The uncon trollable plating/strippi ng behavior,infinite volume change ...Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have bee n widely studied.However,The uncon trollable plating/strippi ng behavior,infinite volume change and den drites formation of lithium metal anode restrict the applicati on.The unc on trolled n ucleati on of lithium caused by the non uniform multi-physical field distributions,can lead to the undesirable lithium deposition.Herein,a graphene composite uniformly loaded with Ag nano-particles(Ag NPs)is prepared through a facile Gamma ray irradiation method and assembled into self-supported film with layered structure(Ag-rGO film).Whe n such film is used as a lithium metal an ode host,the uncontrolled deposition is converted into a highly nucleation-induced process.On one hand,the Ag NPs distributed between the in terlayers of graphe ne can preferentially induce lithium nu cleati on and en able uniform deposition morphology of lithium between interlayers.On the other hand,the stable layered graphene structure can accommodate volume change,stabilize the interface between anode and electrolyte and inhibit dendrites formation.Therefore,the layered Ag-rGO film as anode host can reach a high Coulombic efficiency over 93.3% for 200 cycle(786 h)at a current density of 1 mA cm^(-2) for 2 mAh cm^(-2) in carbonate-based electrolyte.This work proposes a facile Gamma ray irradiation method to prepare metal/3D-skeleton structure as lithium anode host and demonstrates the potential to regulate the lithium metal deposition behaviors via manipulating the distribution of lithiophilic metal(e.g.Ag)in 3D frameworks.This may offer a practicable thinking for the subsequent design of the lithium metal anode.展开更多
High-pressure chambers filled with gaseous hydrogen (HHPC), deuterium (DHPC) and helium (HeHPC) under different initial pressures from about I kbar up to 3 kbar were irradiated with braking γ-rays of threshold ...High-pressure chambers filled with gaseous hydrogen (HHPC), deuterium (DHPC) and helium (HeHPC) under different initial pressures from about I kbar up to 3 kbar were irradiated with braking γ-rays of threshold energy 10 MeV during varying periods of exposure at the electron beam currents 22-24μA. Upon opening of these chambers, a lot of new synthesized structures with unusual element compositions very different from the initial ones were found. The described phenomena agree well with a series of studies by authors carried out under the action of γ-rays on dense gases of hydrogen, deuterium and helium in the presence of chosen metals in the reaction chamber.展开更多
Diamond like carbon films, prepared by RF glow discharge on glass substrates, were irradiated by γ rays. The as deposited and irradiated films were characterized by Raman spectroscopy, electrical resistivity, a...Diamond like carbon films, prepared by RF glow discharge on glass substrates, were irradiated by γ rays. The as deposited and irradiated films were characterized by Raman spectroscopy, electrical resistivity, and infrared transmittance. It is shown that the irradiation of the γ rays can lead to the breaking of SP 3 C H and SP 2 C H bonds, slight increasing of SP 3 C C bonds, and induced hydrogen recombination with H 2 molecules, subsequently diffusing to the surface of the films. When the γ rays irradiation dose reached 10×10 4 Gy, the numbers of SP 3 C H bonds was decreased by about 50%, the resistivity of irradiated DLC films was increased, and the diamond like character of the films became more obvious. The structure of DLC films was modified when irradiated by γ rays. The irradiation mechanisms are briefly discussed.展开更多
The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain g...The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain genetic mutants necessary to improve production. It is in this context that we undertook this study to evaluate the effects induced on the cultivation of peanut seeds irradiated by X-rays at low doses applied in radiotherapy. X-ray irradiation of four (2, 3, 4, 5) lots of peanuts are performed with respectively 0.5, 1.5, 2 and 4 Gray using the cobalt 60 therapy device (Alcyon II). The seeding of the seeds and then the following-up of the crops during 35 days allowed us to study the parameters of germination, growth and yield. The results obtained after monitoring revealed that the irradiation did not have any significant impact on germination and would appear to temporarily inhibit the growth rate compared to the control batch. However, the decrease in weight of the harvested seeds can be explained by the absence of fertilizer during the cultivation.展开更多
Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and d...Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and developed by authors in this paper; planar segments are used as the reflection mirror instead of curved segments because of the simple process and low cost. After the complex assembling process with a special metal supporter, a final circle light spot of φ 12 mm was obtained in the visible light testing experiment of GIO; the effective area of 1710.51 mm^2@ 1 keV and 530 mm^2@8 keV is obtained in the x-ray testing experiment with the GIO-SDD combination, which is supposed to be a concentrating detector in xray detection systems.展开更多
This paper mainly reports the permanent impact of displacement damage induced by heavy-ion strikes on the deepsubmicron MOSFETs. Upon the heavy ion track through the device, it can lead to displacement damage, includi...This paper mainly reports the permanent impact of displacement damage induced by heavy-ion strikes on the deepsubmicron MOSFETs. Upon the heavy ion track through the device, it can lead to displacement damage, including the vacancies and the interstitials. As the featured size of device scales down, the damage can change the dopant distribution in the channel and source/drain regions through the generation of radiation-induced defects and thus have significant impacts on their electrical characteristics. The measured results show that the radiation-induced damage can cause DC characteristics degradations including the threshold voltage, subthreshold swing, saturation drain current, transconductanee, etc. The radiation-induced displacement damage may become the dominant issue while it was the secondary concern for the traditional devices after the heavy ion irradiation. The samples are also irradiated by Co- 60 gamma ray for comparison with the heavy ion irradiation results. Corresponding explanations and analysis are discussed.展开更多
Irradiation protection of the nonlinear optical devices used in the spacecraft and next generation active laser system must be solved. The first problem was to find the irradiation damage mechanism of the nonlinear ma...Irradiation protection of the nonlinear optical devices used in the spacecraft and next generation active laser system must be solved. The first problem was to find the irradiation damage mechanism of the nonlinear materials. In this paper the irradiation electronic field originating from high speed charged particle beams was discussed. The calculating model of the electronic field, based on the relativistic mechanics and electro-magnetic theory, was founded. The common characters of the irradiation electronic field were predicted and the fields of α ray and β ray were calculated by means of our model. The simulating results showed that the intensity of the electric field increased with the energy or the intensity of the beam. The results also showed that the field change trend of α ray and β ray was similar, but the field value was quite different. When the beam intensity I = 100 μA and the beam energy εm = 500 Mev, the electronic field values were about 3.5 × 107 v/m for α ray and 2.4 × 1011 v/m for β ray.展开更多
Gamma radiation is an effective tool for inducing genetic variation in plant characters. In the present experiment, M<sub>5</sub> mulberry variety juvenile twigs were subjected to source Co<sup>60<...Gamma radiation is an effective tool for inducing genetic variation in plant characters. In the present experiment, M<sub>5</sub> mulberry variety juvenile twigs were subjected to source Co<sup>60</sup> gamma irradiation (1 kR - 10 kR)</span><span> </span><span style="font-family:"">and mutants grown in triplicates in randomized block design to raise M<sub>1</sub> and M<sub>2</sub><sup> </sup>generation. In M<sub>2</sub> generation plants were subjected to phytochemical and bioassay tests. Silkworm rearing parameters and commercial characters of cocoons were recorded by feeding cross breed silkworms. Results show that M<sub>5</sub> mutant leaves revealed significant variations in phytochemical constituents and moisture content. Bioassay tests recorded significant differences compared to control in M<sub>2</sub> generation. Commercial characters like cocoon weight (1.41 g), shell weight (0.24 g), shell percentage (16.29 %), filament length (821.00 mts), renditta (8.2), denier (2.24) and effective rate of rearing (92.14 %) were increased. It is concluded </span><span style="font-family:"">that, gamma rays treatment enhances the mulberry plants leaf </span><span style="font-family:"">bioactive components, silkworm rearing and cocoon parameters<b> </b>and shows beneficial variants in M<sub>2</sub> generation.展开更多
Between October 1985 and June 1992 Postoperative kelolds of 125 Patients were treated with superficial X-ray (100-140 Kv) and electron beam (6 and 9 MeV ), in an attempt to prevent their recurrence, 100 patients with ...Between October 1985 and June 1992 Postoperative kelolds of 125 Patients were treated with superficial X-ray (100-140 Kv) and electron beam (6 and 9 MeV ), in an attempt to prevent their recurrence, 100 patients with 129 sites received a dose of 1200-4000 cGy at 200-300 cGy per fraction within one to four weeks and at intervals of one to three weeks between excision and irradiation. Rate of success In the prevention of kelold was only 28. 6% (37/ 129). However, 25 patients with 25 sites received a total dose of 1500 cGy at 500 cGy per fraction starting within one week after excision and at Intervals of 96 hours. The success rate was 84% (21/25).展开更多
A high-efficiency synthesis method for a latent pigment of red pigment diketo-pyrrolo-pyrrole (Pig. Red 272:272DPP), which is important as a functional organic pigment, was investigated, and the investigation results ...A high-efficiency synthesis method for a latent pigment of red pigment diketo-pyrrolo-pyrrole (Pig. Red 272:272DPP), which is important as a functional organic pigment, was investigated, and the investigation results revealed that irradiation of microwaves (MWs) for several seconds to 272 DPP in NMP (N-methyl-2-pyrrolidone) solvent yielded DPP latent pigment (272DPP-BOC) at a high yield of 86.2%. Two kinds of latent-pigment crystals, namely, red and yellow, were obtained by recrystallization, and it was found that the fluorescence-emission properties of the two kinds differ significantly. Single-crystal X-ray structural analysis showed that the difference in the fluorescence-emission properties of the two types is derived from the difference in their crystal structures.展开更多
The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and...The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and ms.This beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic loads.In addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive engines.The light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid nitrogen.This CPMU can generate X-ray photons within an energy range of 8.7-30 keV.The beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam path.Four X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative micro-CT.Furthermore,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray chamber.Following the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023.展开更多
Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain lar...Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC).Methods The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine.Results In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions.Conclusions These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.展开更多
The persistent luminescence(PersL)dependence on the dopants and derived mechanism of trapping and de-trapping processes were investigated in Y3Al2Ga3O12(YAGG)based nanophosphor,doped with Ce^3+and/or Cr^3+.It is found...The persistent luminescence(PersL)dependence on the dopants and derived mechanism of trapping and de-trapping processes were investigated in Y3Al2Ga3O12(YAGG)based nanophosphor,doped with Ce^3+and/or Cr^3+.It is found that the presence of Cr^3+ions produce electron and hole traps and capture suitable charge after X-ray irradiation.The effect of irradiation on the carriers trapping and their pathways after excitation was studied by means of thermo luminescence technique.On the other hand,for blue light irradiation the mechanism seems to be different.In the latter case,the Ce^3+ions,having the position of energy levels in the conduction band,become sensitizers for the electrons and main emission centres for the PersL(de-trapping process goes through Ce^3+).展开更多
Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LU...Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases.展开更多
Wettability manipulation of glancing angle deposited Fe/Co/Ni nanorod arrays was realized by X-ray irradiation in ultra-high vacuum chamber. Reversible transition was also purchased by alternating ethanol immersion an...Wettability manipulation of glancing angle deposited Fe/Co/Ni nanorod arrays was realized by X-ray irradiation in ultra-high vacuum chamber. Reversible transition was also purchased by alternating ethanol immersion and X-ray irradiation. Alkyl group adsorption-desorption mechanism and corresponding morphology depen- dence of wettability manipulation were revealed.展开更多
Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx carcinoma cell lines (Hep-2) which were irradiated by different doses of X-ray. The results show that (1) the irrad...Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx carcinoma cell lines (Hep-2) which were irradiated by different doses of X-ray. The results show that (1) the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, (2) the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and (3) the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry (FCM) primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum (20.36%), but the apoptotic ratios of the 2 to 8 Gy dose groups change little.展开更多
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 391702750)
文摘Objective To observe the effects of signal factors of corticosterone (CS), cAMP, cGMP, Ca^2+ and protein kinase C (PKC) on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA lyric rate for thymocytes was measured by fluomspectrophotometry. Results The DNA lyric rate for thymocytes 4-8 hours after irradiation with 2-8 Gy was significantly higher than that in the control (P〈0.01). As compared with the control, the DNA lyric rate for thymocytes treated with 0.01 μnol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.05-0.4 μg/mL ionomycin (Iono, P〈0.05 or P〈0.01) or 0.05-0.4 ng/mL phorbol myristate acetate (PMA, P〈0.05 or P〈0.01), respectively, was significantly increased, while the rate for thymocytes treated with 50 ng/mL cGMP was not significantly increased. The DNA lyric rate for thymocytes treated with 0.01 μmol/L CS (P〈0.01), 50 ng/mL cAMP (P〈0.01), 0.2 and 0.4 μg/mL Iono (P〈0.05), and 0.2 and 0.4 ng/mL PMA (P〈0.05) plus 4-Gy irradiation, respectively, was significantly higher than that treated with single 4-Gy irradiation, while the rate for thymocytes treated with 50 ng/mL cGMP plus 4-Gy irradiation was not increased. When both 0.4 I.tg/mL Iono and 0.4 ng/mL PMA acted on the thymocytes, the DNA lyric rate for thymocytes was significantly higher than that in the control (P〈0.01), the DNA lytic rate for thymocytes treated with both 0.4 μg/mL Iono and 0.4 ng/mL PMA plus 4-Gy irradiation was significantly higher than that treated with single 4-Gy irradiation (P〈0.05), but was Iono plus 4-Gy irradiation or 0.4 ng/mL PMA plus 4-Gy irradiation. can promote thymocyte apoptosis induced by larger dose X-rays. not significantly higher than that treated with 0.4 μg/mL Conclusion CS, cAMP, Ca^2+, and PKC signal factors can promote thymocyte apoptosis induced by larger dose X-rays.
基金suported by the National Natural Science Foundation of China (Grant No. 10874242)the National Basic Research Program of China (973 Program) (Grant No. 2007CB815105)Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20070290008)
文摘Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of laser pulse and the overall shape of the intensity distribution in the focal line have different influences on the plasma. Calculations show that the evolution of temperature variation is more sensitive to the pulse duration and the electron density variation is more sensitive to the pulse intensity. Pulses with duration of 200 ps to 500 ps and with intensity of 0.2 TW/cm2 to 1.0 TW/cm2 are proved acceptable in slab x-ray lasers.
基金supported by the National Natural Science Foundation of China, No. 81070982, 81201400Tianjin Research Program of Application Foundation and Advanced Technology, No. 10JCZDJC18800, 13JCQNJC11100the Research Foundation of Tianjin Health Bureau, No. 09kz104
文摘X-irradiation has a beneficial effect in treating spinal cord injury. We supposed that X-irradiation could improve the microenvironment at the site of a spinal cord injury and inhibit glial scar formation. Thus, this study was designed to observe the effects of 8 Gy X-irradiation on the injury site at 6 hours and 2, 4, 7, and 14 days post injury, in terms of improvement in the microenvironment and hind limb motor function. Immunohistochemistry showed that the expression of macrophage marker ED-1 and the area with glial scar formation were reduced. In addition, the Basso, Beattie and Bresnahan score was higher at 7 days post injury relative to the other time points post injury. Results indicated that X-irradiation at a dose of 8 Gy can inhibit glial scar formation and alleviate the inflammatory reaction, thereby repairing spinal cord injury. X-irradiation at 7 days post spinal cord injury may be the best time window.
基金support from the National Natural Science Foundation of China(Grant No.21875195,21875198 and 22005257)the Fundamental Research Funds for the Central Universities(20720190040).
文摘Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have bee n widely studied.However,The uncon trollable plating/strippi ng behavior,infinite volume change and den drites formation of lithium metal anode restrict the applicati on.The unc on trolled n ucleati on of lithium caused by the non uniform multi-physical field distributions,can lead to the undesirable lithium deposition.Herein,a graphene composite uniformly loaded with Ag nano-particles(Ag NPs)is prepared through a facile Gamma ray irradiation method and assembled into self-supported film with layered structure(Ag-rGO film).Whe n such film is used as a lithium metal an ode host,the uncontrolled deposition is converted into a highly nucleation-induced process.On one hand,the Ag NPs distributed between the in terlayers of graphe ne can preferentially induce lithium nu cleati on and en able uniform deposition morphology of lithium between interlayers.On the other hand,the stable layered graphene structure can accommodate volume change,stabilize the interface between anode and electrolyte and inhibit dendrites formation.Therefore,the layered Ag-rGO film as anode host can reach a high Coulombic efficiency over 93.3% for 200 cycle(786 h)at a current density of 1 mA cm^(-2) for 2 mAh cm^(-2) in carbonate-based electrolyte.This work proposes a facile Gamma ray irradiation method to prepare metal/3D-skeleton structure as lithium anode host and demonstrates the potential to regulate the lithium metal deposition behaviors via manipulating the distribution of lithiophilic metal(e.g.Ag)in 3D frameworks.This may offer a practicable thinking for the subsequent design of the lithium metal anode.
文摘High-pressure chambers filled with gaseous hydrogen (HHPC), deuterium (DHPC) and helium (HeHPC) under different initial pressures from about I kbar up to 3 kbar were irradiated with braking γ-rays of threshold energy 10 MeV during varying periods of exposure at the electron beam currents 22-24μA. Upon opening of these chambers, a lot of new synthesized structures with unusual element compositions very different from the initial ones were found. The described phenomena agree well with a series of studies by authors carried out under the action of γ-rays on dense gases of hydrogen, deuterium and helium in the presence of chosen metals in the reaction chamber.
文摘Diamond like carbon films, prepared by RF glow discharge on glass substrates, were irradiated by γ rays. The as deposited and irradiated films were characterized by Raman spectroscopy, electrical resistivity, and infrared transmittance. It is shown that the irradiation of the γ rays can lead to the breaking of SP 3 C H and SP 2 C H bonds, slight increasing of SP 3 C C bonds, and induced hydrogen recombination with H 2 molecules, subsequently diffusing to the surface of the films. When the γ rays irradiation dose reached 10×10 4 Gy, the numbers of SP 3 C H bonds was decreased by about 50%, the resistivity of irradiated DLC films was increased, and the diamond like character of the films became more obvious. The structure of DLC films was modified when irradiated by γ rays. The irradiation mechanisms are briefly discussed.
文摘The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain genetic mutants necessary to improve production. It is in this context that we undertook this study to evaluate the effects induced on the cultivation of peanut seeds irradiated by X-rays at low doses applied in radiotherapy. X-ray irradiation of four (2, 3, 4, 5) lots of peanuts are performed with respectively 0.5, 1.5, 2 and 4 Gray using the cobalt 60 therapy device (Alcyon II). The seeding of the seeds and then the following-up of the crops during 35 days allowed us to study the parameters of germination, growth and yield. The results obtained after monitoring revealed that the irradiation did not have any significant impact on germination and would appear to temporarily inhibit the growth rate compared to the control batch. However, the decrease in weight of the harvested seeds can be explained by the absence of fertilizer during the cultivation.
基金supported by the National Natural Science Foundation of China(Grant No.61471357)the State Key Laboratory of Geo-Information Engineering Foundation(Grant No.SKLGIE2014-M-2-1)
文摘Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and developed by authors in this paper; planar segments are used as the reflection mirror instead of curved segments because of the simple process and low cost. After the complex assembling process with a special metal supporter, a final circle light spot of φ 12 mm was obtained in the visible light testing experiment of GIO; the effective area of 1710.51 mm^2@ 1 keV and 530 mm^2@8 keV is obtained in the x-ray testing experiment with the GIO-SDD combination, which is supposed to be a concentrating detector in xray detection systems.
基金Project supported by the National Natural Science Foundation of China (Grants No. 60625403,60836004,60925015 and 90207004)the Major State Basic Research Development Program of China (973 Program) (Grant No. 2006CB302701)
文摘This paper mainly reports the permanent impact of displacement damage induced by heavy-ion strikes on the deepsubmicron MOSFETs. Upon the heavy ion track through the device, it can lead to displacement damage, including the vacancies and the interstitials. As the featured size of device scales down, the damage can change the dopant distribution in the channel and source/drain regions through the generation of radiation-induced defects and thus have significant impacts on their electrical characteristics. The measured results show that the radiation-induced damage can cause DC characteristics degradations including the threshold voltage, subthreshold swing, saturation drain current, transconductanee, etc. The radiation-induced displacement damage may become the dominant issue while it was the secondary concern for the traditional devices after the heavy ion irradiation. The samples are also irradiated by Co- 60 gamma ray for comparison with the heavy ion irradiation results. Corresponding explanations and analysis are discussed.
文摘Irradiation protection of the nonlinear optical devices used in the spacecraft and next generation active laser system must be solved. The first problem was to find the irradiation damage mechanism of the nonlinear materials. In this paper the irradiation electronic field originating from high speed charged particle beams was discussed. The calculating model of the electronic field, based on the relativistic mechanics and electro-magnetic theory, was founded. The common characters of the irradiation electronic field were predicted and the fields of α ray and β ray were calculated by means of our model. The simulating results showed that the intensity of the electric field increased with the energy or the intensity of the beam. The results also showed that the field change trend of α ray and β ray was similar, but the field value was quite different. When the beam intensity I = 100 μA and the beam energy εm = 500 Mev, the electronic field values were about 3.5 × 107 v/m for α ray and 2.4 × 1011 v/m for β ray.
文摘Gamma radiation is an effective tool for inducing genetic variation in plant characters. In the present experiment, M<sub>5</sub> mulberry variety juvenile twigs were subjected to source Co<sup>60</sup> gamma irradiation (1 kR - 10 kR)</span><span> </span><span style="font-family:"">and mutants grown in triplicates in randomized block design to raise M<sub>1</sub> and M<sub>2</sub><sup> </sup>generation. In M<sub>2</sub> generation plants were subjected to phytochemical and bioassay tests. Silkworm rearing parameters and commercial characters of cocoons were recorded by feeding cross breed silkworms. Results show that M<sub>5</sub> mutant leaves revealed significant variations in phytochemical constituents and moisture content. Bioassay tests recorded significant differences compared to control in M<sub>2</sub> generation. Commercial characters like cocoon weight (1.41 g), shell weight (0.24 g), shell percentage (16.29 %), filament length (821.00 mts), renditta (8.2), denier (2.24) and effective rate of rearing (92.14 %) were increased. It is concluded </span><span style="font-family:"">that, gamma rays treatment enhances the mulberry plants leaf </span><span style="font-family:"">bioactive components, silkworm rearing and cocoon parameters<b> </b>and shows beneficial variants in M<sub>2</sub> generation.
文摘Between October 1985 and June 1992 Postoperative kelolds of 125 Patients were treated with superficial X-ray (100-140 Kv) and electron beam (6 and 9 MeV ), in an attempt to prevent their recurrence, 100 patients with 129 sites received a dose of 1200-4000 cGy at 200-300 cGy per fraction within one to four weeks and at intervals of one to three weeks between excision and irradiation. Rate of success In the prevention of kelold was only 28. 6% (37/ 129). However, 25 patients with 25 sites received a total dose of 1500 cGy at 500 cGy per fraction starting within one week after excision and at Intervals of 96 hours. The success rate was 84% (21/25).
文摘A high-efficiency synthesis method for a latent pigment of red pigment diketo-pyrrolo-pyrrole (Pig. Red 272:272DPP), which is important as a functional organic pigment, was investigated, and the investigation results revealed that irradiation of microwaves (MWs) for several seconds to 272 DPP in NMP (N-methyl-2-pyrrolidone) solvent yielded DPP latent pigment (272DPP-BOC) at a high yield of 86.2%. Two kinds of latent-pigment crystals, namely, red and yellow, were obtained by recrystallization, and it was found that the fluorescence-emission properties of the two kinds differ significantly. Single-crystal X-ray structural analysis showed that the difference in the fluorescence-emission properties of the two types is derived from the difference in their crystal structures.
基金supported by the CAS Project for Young Scientists in Basic Research(YSBR-096)the National Major Scientific Instruments and Equipment Development Project of China(No.11627901)+1 种基金the National Key Research and Development Program of China(Nos.2021YFF0701202,2021YFA1600703)the National Natural Science Foundation of China(Nos.U1932205,12275343).
文摘The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and ms.This beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic loads.In addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive engines.The light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid nitrogen.This CPMU can generate X-ray photons within an energy range of 8.7-30 keV.The beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam path.Four X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative micro-CT.Furthermore,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray chamber.Following the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023.
基金This work was supported by grants from the National Natural Science Foundation of China (No. 30973434 and No. 30772577), the Grant for Development of Science and Technology from Department of Science and Technology of Guangzhou, China (No. 2008Z1-E241), and the Grant for Development of Important New Drugs from Ministry of Health of China (No. 2009ZX09303-007).
文摘Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC).Methods The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine.Results In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions.Conclusions These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.
基金Project supported by the Polish National Science Centre(OPUS 11#2016/21/B/ST5/02385)
文摘The persistent luminescence(PersL)dependence on the dopants and derived mechanism of trapping and de-trapping processes were investigated in Y3Al2Ga3O12(YAGG)based nanophosphor,doped with Ce^3+and/or Cr^3+.It is found that the presence of Cr^3+ions produce electron and hole traps and capture suitable charge after X-ray irradiation.The effect of irradiation on the carriers trapping and their pathways after excitation was studied by means of thermo luminescence technique.On the other hand,for blue light irradiation the mechanism seems to be different.In the latter case,the Ce^3+ions,having the position of energy levels in the conduction band,become sensitizers for the electrons and main emission centres for the PersL(de-trapping process goes through Ce^3+).
文摘Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases.
文摘Wettability manipulation of glancing angle deposited Fe/Co/Ni nanorod arrays was realized by X-ray irradiation in ultra-high vacuum chamber. Reversible transition was also purchased by alternating ethanol immersion and X-ray irradiation. Alkyl group adsorption-desorption mechanism and corresponding morphology depen- dence of wettability manipulation were revealed.
基金the Science and Technol-ogy Department of Henan province (No.0624410052)the key Ion Beam Bioengineering Laboratory of Henan Province+1 种基金the Pathology Laboratory of Zhengzhou Uni-versitythe People's Hospital of Henan Province.
文摘Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx carcinoma cell lines (Hep-2) which were irradiated by different doses of X-ray. The results show that (1) the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, (2) the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and (3) the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry (FCM) primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum (20.36%), but the apoptotic ratios of the 2 to 8 Gy dose groups change little.