Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminu...Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.展开更多
Ferroptosis plays a key role in aggravating the progression of spinal cord injury(SCI),but the specific mechanism remains unknown.In this study,we constructed a rat model of T10 SCI using a modified Allen method.We id...Ferroptosis plays a key role in aggravating the progression of spinal cord injury(SCI),but the specific mechanism remains unknown.In this study,we constructed a rat model of T10 SCI using a modified Allen method.We identified 48,44,and 27 ferroptosis genes that were differentially expressed at 1,3,and 7 days after SCI induction.Compared with the sham group and other SCI subgroups,the subgroup at 1 day after SCI showed increased expression of the ferroptosis marker acyl-CoA synthetase long-chain family member 4 and the oxidative stress marker malondialdehyde in the injured spinal cord while glutathione in the injured spinal cord was lower.These findings with our bioinformatics results suggested that 1 day after SCI was the important period of ferroptosis progression.Bioinformatics analysis identified the following top ten hub ferroptosis genes in the subgroup at 1 day after SCI:STAT3,JUN,TLR4,ATF3,HMOX1,MAPK1,MAPK9,PTGS2,VEGFA,and RELA.Real-time polymerase chain reaction on rat spinal cord tissue confirmed that STAT3,JUN,TLR4,ATF3,HMOX1,PTGS2,and RELA mRNA levels were up-regulated and VEGFA,MAPK1 and MAPK9 mRNA levels were down-regulated.Ten potential compounds were predicted using the DSigDB database as potential drugs or molecules targeting ferroptosis to repair SCI.We also constructed a ferroptosis-related mRNA-miRNA-lncRNA network in SCI that included 66 lncRNAs,10 miRNAs,and 12 genes.Our results help further the understanding of the mechanism underlying ferroptosis in SCI.展开更多
Ultra-precision diamond cutting is a promising machining technique for realizing ultra-smooth surface of different kinds of materials.While fundamental understanding of the impact of workpiece material properties on c...Ultra-precision diamond cutting is a promising machining technique for realizing ultra-smooth surface of different kinds of materials.While fundamental understanding of the impact of workpiece material properties on cutting mechanisms is crucial for promoting the capability of the machining technique,numerical simulation methods at different length and time scales act as important supplements to experimental investigations.In this work,we present a compact review on recent advancements in the numerical simulations of material-oriented diamond cutting,in which representative machining phenomena are systematically summarized and discussed by multiscale simulations such as molecular dynamics simulation and finite element simulation:the anisotropy cutting behavior of polycrystalline material,the thermo-mechanical coupling tool-chip friction states,the synergetic cutting responses of individual phase in composite materials,and the impact of various external energetic fields on cutting processes.In particular,the novel physics-based numerical models,which involve the high precision constitutive law associated with heterogeneous deformation behavior,the thermo-mechanical coupling algorithm associated with tool-chip friction,the configurations of individual phases in line with real microstructural characteristics of composite materials,and the integration of external energetic fields into cutting models,are highlighted.Finally,insights into the future development of advanced numerical simulation techniques for diamond cutting of advanced structured materials are also provided.The aspects reported in this review present guidelines for the numerical simulations of ultra-precision mechanical machining responses for a variety of materials.展开更多
Hemorrhagic shock is a life-threatening disease often encountered in emergency departments(EDs).Hemorrhagic shock caused by extensive bleeding from multiple sites is often associated with high mortality and morbidity....Hemorrhagic shock is a life-threatening disease often encountered in emergency departments(EDs).Hemorrhagic shock caused by extensive bleeding from multiple sites is often associated with high mortality and morbidity.In recent years,resuscitative endovascular balloon occlusion of the aorta(REBOA)has been widely used in traumatic hemorrhagic shock and is considered to be an effective resuscitation measure.[1]Some studies reported that REBOA was also effective for non-traumatic hemorrhage.[2,3]In this study,we report a case of hemorrhagic shock caused by acute upper gastrointestinal bleeding that was successfully treated and received REBOA to obtain a transition time.This report may provide feasible options for emergency physicians,gastroenterologists,or surgeons to more actively treat refractory gastrointestinal bleeding.展开更多
Background Docosahexaenoic acid(DHA)and calcidiol could be enriched in chicken for improving public nutrition and health.It remains unclear if supranutritional levels of DHA and calcidiol impair growth performance or ...Background Docosahexaenoic acid(DHA)and calcidiol could be enriched in chicken for improving public nutrition and health.It remains unclear if supranutritional levels of DHA and calcidiol impair growth performance or metabolism of broiler chickens.This study was to determine singular and combined effects of high levels of supplemental DHA-rich microalgal biomass or oil and calcidiol on growth performance,concentrations of triglycerides,cholesterol,and nonesterfied fatty acids in plasma,liver,breast,and thigh,and biophysical properties of tibia.Methods In Exp.1,144 day-old Cornish chicks were divided into 4 groups(6 cages/treatment,6 birds/cage),and were fed a corn-soybean meal basal diet(BD),BD+10,000 IU calcidiol/kg(BD+Cal),BD HA),and BD+1%DHA-rich Aurantiochytrium(1.2 g DHA/kg;BD+D+Cal+DHA for 6 weeks.In Exp.2,180 day-old chicks were divided into5 groups,and were fed:BD,BD+DHA(0.33%to 0.66%oil,1.5 to 3.0 g DHA/kg),BD EPA/kg),BD+DHA+EPA(1.9%to 3.8%eicosapentaenoic acid-rich Nannochloropsis sp.CO18,0.3 to 0.6 g BD+DHA+calcidiol(6000 to 12,000 IU/kg diet),and+DHA+EPA+Cal for 6 weeks.Results Birds fed BD+Cal diet in Exp.1 and BD lower(P+DHA<0.05)+EPA diet in Exp.2 had higher(P<0.05)body weight gain(10%-11%)and gain:feed ratio(7%),and total cholesterol and triglyceride concentrations in plasma(18%-54%),liver(8%-26%),breast(19%-26%),and thigh(10%-19%),respectively,over the controls.The two diets also improved(P<0.05)tibial breaking strength(8%-24%),total bone volume(2%-13%),and(or)bone mineral density(3%-19%)of chickens.Conclusion Supranutrition of dietary calcidiol and DHA alone or together did not produce adverse effects,but led to moderate improvements of growth performance,lipid profiles of plasma and muscle,and bone properties of broiler chickens.展开更多
Synthetic biology efforts have also led to the development of photosynthetic cyanobacteria as"autotrophic cell factories"for biosynthesis of various biofuels directly from CO_(2).However,the low tolerance to...Synthetic biology efforts have also led to the development of photosynthetic cyanobacteria as"autotrophic cell factories"for biosynthesis of various biofuels directly from CO_(2).However,the low tolerance to toxicity of biofuels has restricted the economic application of cyanobacterial hosts.In this study,RNAseq transcriptomics was employed to reveal stress responses to exogenous n-hexane in Synechocystis sp.PCC 6803.Functional enrichment analysis of the transcriptomic data showed that signal transduction systems were induced significantly.To further identify regulatory genes related to n-hexane tolerance,a library of transcriptional regulators(TRs)deletion mutants was then screened for their roles in nhexane tolerance.The results showed that a knockout mutant of slr0724 that encodes an Hta R suppressor protein was more tolerant to n-hexane than the wild type,indicating the involvement of slr0724 in nhexane tolerance.This study provides the foundation for better understanding the cellular responses to n-hexane in Synechocystis sp.PCC 6803,which could contribute to the further engineering of nhexane tolerance in cyanobacteria.展开更多
A vertical GaN field-effect transistor with an integrated self-adapted channel diode(CD-FET)is proposed to improve the reverse conduction performance.It features a channel diode(CD)formed between a trench source on th...A vertical GaN field-effect transistor with an integrated self-adapted channel diode(CD-FET)is proposed to improve the reverse conduction performance.It features a channel diode(CD)formed between a trench source on the insulator and a P-type barrier layer(PBL),together with a P-shield layer under the trench gate.At forward conduction,the CD is pinched off due to depletion effects caused by both the PBL and the metal-insulator-semiconductor structure from the trench source,without influencing the on-state characteristic of the CD-FET.At reverse conduction,the depletion region narrows and thus the CD turns on to achieve a very low turn-on voltage(V_(F)),preventing the inherent body diode from turning on.Meanwhile,the PBL and P-shield layer can modulate the electric field distribution to improve the off-state breakdown voltage(BV).Moreover,the P-shield not only shields the gate from a high electric field but also transforms part of C_(GD)to CGS so as to significantly reduce the gate charge(Q_(GD)),leading to a low switching loss(E_(switch)).Consequently,the proposed CD-FET achieves a low V_(F)of 1.65 V and a high BV of 1446 V,and V_(F),Q_(GD)and E_(switch)of the CD-FET are decreased by 49%,55%and 80%,respectively,compared with those of a conventional metal-oxide-semiconductor field-effect transistor(MOSFET).展开更多
Considering the significance of low-energy electrons(LEEs;0–20 eV) in radiobiology, the sensitization potential of gold nanoparticles(AuNPs) as high-flux LEE emitters when irradiated with sub-keV electrons has been s...Considering the significance of low-energy electrons(LEEs;0–20 eV) in radiobiology, the sensitization potential of gold nanoparticles(AuNPs) as high-flux LEE emitters when irradiated with sub-keV electrons has been suggested. In this study, a track-structure Monte Carlo simulation code using the dielectric theory was developed to simulate the transport of electrons below 50 keV in gold. In this code, modifications, particularly for elastic scattering, are implemented for a more precise description of the LEE emission in secondary electron emission. This code was validated using the secondary electron yield and backscattering coefficient. To ensure dosimetry accuracy, we further verified the code for energy deposition calculations using the Monte Carlo toolkit, Geant4. The development of this code provides a basis for future studies regarding the role of AuNPs in targeted radionuclide radiotherapy.展开更多
After drawbacks and shortages of using conventional kV or MV imaging mode were analyzed, this study proposes a new position verification mode with using the energy larger than 15 MeV or nominal accelerating potential ...After drawbacks and shortages of using conventional kV or MV imaging mode were analyzed, this study proposes a new position verification mode with using the energy larger than 15 MeV or nominal accelerating potential greater than 25 MV X-Ray. The new position verification mode is named HMV imaging mode. Along with the comparison of theoretical analyses, phantom experiments and clinical results to the original imaging modes, this report is going to demonstrate the HMV imaging mode is superior to traditional kV and MV imaging modes. This report first theoretically analyzed three main effects of X-ray interacting with medium by numerous equations and compared their mass attenuation coefficient with different types of tissue. X-ray irradiated on a “Catphan 500” cylinder phantom with different energies to verify these theoretical results. Furthermore, based on phantom experiments’ results, we have done numerous clinical trials and comparisons with patient’s clinical results. The theoretical and experimental results illustrate that the scanned images from HMV mode have a good quality and have ability to identify different tissue components clearly. HMV imaging mode overcomes drawbacks of position verification from both kV and MV level imaging mode as well as keeping advantages of kV and MV imaging mode. The result indicates that HMV is a good position verification mode in radiotherapy.展开更多
Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for...Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui(GV14) and Mingmen(GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.展开更多
基金the National Natural Science Foundation of China(No.12172052 and No.12132003).
文摘Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.
基金supported by National Key Research and Development Project of Stem Cell and Transformation Research,No.2019YFA0112100Tianjin Key Research and Development Plan,Key Projects for Science and Technology Support,No.19YFZCSY00660(both to SQF)。
文摘Ferroptosis plays a key role in aggravating the progression of spinal cord injury(SCI),but the specific mechanism remains unknown.In this study,we constructed a rat model of T10 SCI using a modified Allen method.We identified 48,44,and 27 ferroptosis genes that were differentially expressed at 1,3,and 7 days after SCI induction.Compared with the sham group and other SCI subgroups,the subgroup at 1 day after SCI showed increased expression of the ferroptosis marker acyl-CoA synthetase long-chain family member 4 and the oxidative stress marker malondialdehyde in the injured spinal cord while glutathione in the injured spinal cord was lower.These findings with our bioinformatics results suggested that 1 day after SCI was the important period of ferroptosis progression.Bioinformatics analysis identified the following top ten hub ferroptosis genes in the subgroup at 1 day after SCI:STAT3,JUN,TLR4,ATF3,HMOX1,MAPK1,MAPK9,PTGS2,VEGFA,and RELA.Real-time polymerase chain reaction on rat spinal cord tissue confirmed that STAT3,JUN,TLR4,ATF3,HMOX1,PTGS2,and RELA mRNA levels were up-regulated and VEGFA,MAPK1 and MAPK9 mRNA levels were down-regulated.Ten potential compounds were predicted using the DSigDB database as potential drugs or molecules targeting ferroptosis to repair SCI.We also constructed a ferroptosis-related mRNA-miRNA-lncRNA network in SCI that included 66 lncRNAs,10 miRNAs,and 12 genes.Our results help further the understanding of the mechanism underlying ferroptosis in SCI.
基金support from the National Natural Science Foundation of China(52275416 and 51905194)National Key Research and Development Program(2021YFC2202303)Science Challenge Project(No.TZ2018006-0201-02)。
文摘Ultra-precision diamond cutting is a promising machining technique for realizing ultra-smooth surface of different kinds of materials.While fundamental understanding of the impact of workpiece material properties on cutting mechanisms is crucial for promoting the capability of the machining technique,numerical simulation methods at different length and time scales act as important supplements to experimental investigations.In this work,we present a compact review on recent advancements in the numerical simulations of material-oriented diamond cutting,in which representative machining phenomena are systematically summarized and discussed by multiscale simulations such as molecular dynamics simulation and finite element simulation:the anisotropy cutting behavior of polycrystalline material,the thermo-mechanical coupling tool-chip friction states,the synergetic cutting responses of individual phase in composite materials,and the impact of various external energetic fields on cutting processes.In particular,the novel physics-based numerical models,which involve the high precision constitutive law associated with heterogeneous deformation behavior,the thermo-mechanical coupling algorithm associated with tool-chip friction,the configurations of individual phases in line with real microstructural characteristics of composite materials,and the integration of external energetic fields into cutting models,are highlighted.Finally,insights into the future development of advanced numerical simulation techniques for diamond cutting of advanced structured materials are also provided.The aspects reported in this review present guidelines for the numerical simulations of ultra-precision mechanical machining responses for a variety of materials.
基金supported by a grant from Health Commission of Zhejiang Province“optimization study on partial balloon occlusion of the aorta in traumatic hemorrhagic shock patients(2023KY774)”.
文摘Hemorrhagic shock is a life-threatening disease often encountered in emergency departments(EDs).Hemorrhagic shock caused by extensive bleeding from multiple sites is often associated with high mortality and morbidity.In recent years,resuscitative endovascular balloon occlusion of the aorta(REBOA)has been widely used in traumatic hemorrhagic shock and is considered to be an effective resuscitation measure.[1]Some studies reported that REBOA was also effective for non-traumatic hemorrhage.[2,3]In this study,we report a case of hemorrhagic shock caused by acute upper gastrointestinal bleeding that was successfully treated and received REBOA to obtain a transition time.This report may provide feasible options for emergency physicians,gastroenterologists,or surgeons to more actively treat refractory gastrointestinal bleeding.
基金funded in part by a DOE MAGIC grant(DE-EE0007091)USDA grant(2019-69012-29905)Cornell University(Hatch grants NYC-127302)。
文摘Background Docosahexaenoic acid(DHA)and calcidiol could be enriched in chicken for improving public nutrition and health.It remains unclear if supranutritional levels of DHA and calcidiol impair growth performance or metabolism of broiler chickens.This study was to determine singular and combined effects of high levels of supplemental DHA-rich microalgal biomass or oil and calcidiol on growth performance,concentrations of triglycerides,cholesterol,and nonesterfied fatty acids in plasma,liver,breast,and thigh,and biophysical properties of tibia.Methods In Exp.1,144 day-old Cornish chicks were divided into 4 groups(6 cages/treatment,6 birds/cage),and were fed a corn-soybean meal basal diet(BD),BD+10,000 IU calcidiol/kg(BD+Cal),BD HA),and BD+1%DHA-rich Aurantiochytrium(1.2 g DHA/kg;BD+D+Cal+DHA for 6 weeks.In Exp.2,180 day-old chicks were divided into5 groups,and were fed:BD,BD+DHA(0.33%to 0.66%oil,1.5 to 3.0 g DHA/kg),BD EPA/kg),BD+DHA+EPA(1.9%to 3.8%eicosapentaenoic acid-rich Nannochloropsis sp.CO18,0.3 to 0.6 g BD+DHA+calcidiol(6000 to 12,000 IU/kg diet),and+DHA+EPA+Cal for 6 weeks.Results Birds fed BD+Cal diet in Exp.1 and BD lower(P+DHA<0.05)+EPA diet in Exp.2 had higher(P<0.05)body weight gain(10%-11%)and gain:feed ratio(7%),and total cholesterol and triglyceride concentrations in plasma(18%-54%),liver(8%-26%),breast(19%-26%),and thigh(10%-19%),respectively,over the controls.The two diets also improved(P<0.05)tibial breaking strength(8%-24%),total bone volume(2%-13%),and(or)bone mineral density(3%-19%)of chickens.Conclusion Supranutrition of dietary calcidiol and DHA alone or together did not produce adverse effects,but led to moderate improvements of growth performance,lipid profiles of plasma and muscle,and bone properties of broiler chickens.
基金supported by grants from the National Key Research and Development Program of China(2020YFA0906800,2021YFA0909700,2018YFA0903600 and 2019YFA0904600)。
文摘Synthetic biology efforts have also led to the development of photosynthetic cyanobacteria as"autotrophic cell factories"for biosynthesis of various biofuels directly from CO_(2).However,the low tolerance to toxicity of biofuels has restricted the economic application of cyanobacterial hosts.In this study,RNAseq transcriptomics was employed to reveal stress responses to exogenous n-hexane in Synechocystis sp.PCC 6803.Functional enrichment analysis of the transcriptomic data showed that signal transduction systems were induced significantly.To further identify regulatory genes related to n-hexane tolerance,a library of transcriptional regulators(TRs)deletion mutants was then screened for their roles in nhexane tolerance.The results showed that a knockout mutant of slr0724 that encodes an Hta R suppressor protein was more tolerant to n-hexane than the wild type,indicating the involvement of slr0724 in nhexane tolerance.This study provides the foundation for better understanding the cellular responses to n-hexane in Synechocystis sp.PCC 6803,which could contribute to the further engineering of nhexane tolerance in cyanobacteria.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61874149 and U20A20208)the Outstanding Youth Science and Technology Foundation of China(Grant No.2018-JCJQ-ZQ-060).
文摘A vertical GaN field-effect transistor with an integrated self-adapted channel diode(CD-FET)is proposed to improve the reverse conduction performance.It features a channel diode(CD)formed between a trench source on the insulator and a P-type barrier layer(PBL),together with a P-shield layer under the trench gate.At forward conduction,the CD is pinched off due to depletion effects caused by both the PBL and the metal-insulator-semiconductor structure from the trench source,without influencing the on-state characteristic of the CD-FET.At reverse conduction,the depletion region narrows and thus the CD turns on to achieve a very low turn-on voltage(V_(F)),preventing the inherent body diode from turning on.Meanwhile,the PBL and P-shield layer can modulate the electric field distribution to improve the off-state breakdown voltage(BV).Moreover,the P-shield not only shields the gate from a high electric field but also transforms part of C_(GD)to CGS so as to significantly reduce the gate charge(Q_(GD)),leading to a low switching loss(E_(switch)).Consequently,the proposed CD-FET achieves a low V_(F)of 1.65 V and a high BV of 1446 V,and V_(F),Q_(GD)and E_(switch)of the CD-FET are decreased by 49%,55%and 80%,respectively,compared with those of a conventional metal-oxide-semiconductor field-effect transistor(MOSFET).
基金supported by the National Natural Science Foundation of China (Nos. 12004180, 21906083, 11975122, and 22006067)the Natural Science Foundation of Jiangsu Province (No. BK20190384)the Fundamental Research Funds for the Central Universities (Nos. NE2020006, NS2022095)。
文摘Considering the significance of low-energy electrons(LEEs;0–20 eV) in radiobiology, the sensitization potential of gold nanoparticles(AuNPs) as high-flux LEE emitters when irradiated with sub-keV electrons has been suggested. In this study, a track-structure Monte Carlo simulation code using the dielectric theory was developed to simulate the transport of electrons below 50 keV in gold. In this code, modifications, particularly for elastic scattering, are implemented for a more precise description of the LEE emission in secondary electron emission. This code was validated using the secondary electron yield and backscattering coefficient. To ensure dosimetry accuracy, we further verified the code for energy deposition calculations using the Monte Carlo toolkit, Geant4. The development of this code provides a basis for future studies regarding the role of AuNPs in targeted radionuclide radiotherapy.
文摘After drawbacks and shortages of using conventional kV or MV imaging mode were analyzed, this study proposes a new position verification mode with using the energy larger than 15 MeV or nominal accelerating potential greater than 25 MV X-Ray. The new position verification mode is named HMV imaging mode. Along with the comparison of theoretical analyses, phantom experiments and clinical results to the original imaging modes, this report is going to demonstrate the HMV imaging mode is superior to traditional kV and MV imaging modes. This report first theoretically analyzed three main effects of X-ray interacting with medium by numerous equations and compared their mass attenuation coefficient with different types of tissue. X-ray irradiated on a “Catphan 500” cylinder phantom with different energies to verify these theoretical results. Furthermore, based on phantom experiments’ results, we have done numerous clinical trials and comparisons with patient’s clinical results. The theoretical and experimental results illustrate that the scanned images from HMV mode have a good quality and have ability to identify different tissue components clearly. HMV imaging mode overcomes drawbacks of position verification from both kV and MV level imaging mode as well as keeping advantages of kV and MV imaging mode. The result indicates that HMV is a good position verification mode in radiotherapy.
基金supported by the National Natural Science Foundation of China(31301895)the Natural Science Fund of Education Department of Anhui Province,China(KJ2018A0402)
基金supported by the Major Special Project of Scientific Research Fund of Yunnan Provincial Education Department of China,No.zd2012001
文摘Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui(GV14) and Mingmen(GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells.