The properties of the combustion and deflagration to detonation transition(DDT)of Al/Fe_(2)O_(3)/RDX hybrid nanocomposites,a type of potentially novel lead-free primary explosives,were tested in weakly confined condit...The properties of the combustion and deflagration to detonation transition(DDT)of Al/Fe_(2)O_(3)/RDX hybrid nanocomposites,a type of potentially novel lead-free primary explosives,were tested in weakly confined conditions,and the interaction of Al/Fe_(2)O_(3)nanothermite and RDX in the DDT process was studied in detail.Results show that the amount of the Al/Fe_(2)O_(3)nanothermite has a great effect on the DDT properties of Al/Fe_(2)O_(3)/RDX nanocomposites.The addition of Al/Fe_(2)O_(3)nanothermite to RDX apparently improves the firing properties of RDX.A small amount of Al/Fe_(2)O_(3)nanothermite greatly increases the initial combustion velocity of Al/Fe_(2)O_(3)/RDX nanocomposites,accelerating their DDT process.When the contents of Al/Fe_(2)O_(3)nanothermite are less than 20 wt%,the DDT mechanisms of Al/Fe_(2)O_(3)/RDX nanocomposites follow the distinct abrupt mode,and are consistent with that of RDX,though their DDT processes are different.The RDX added into the Al/Fe_(2)O_(3)nanothermite increases the latter's peak combustion velocity and makes it generate the DDT when the RDX content is at least 10 wt%.RDX plays a key role in the shock compressive combustion,the formation and the properties of the DDT in the flame propagation of nanocomposites.Compared with RDX,the fast DDT of Al/Fe_(2)O_(3)/RDX nanocomposites could be obtained by adjusting the chemical constituents of nanocomposites.展开更多
BACKGROUND Fibrobronchoscopy is a common adjunct tool that requires anesthesia and is widely used in the diagnosis and treatment of various respiratory diseases.However,current anesthesia methods,such as spray,nebuliz...BACKGROUND Fibrobronchoscopy is a common adjunct tool that requires anesthesia and is widely used in the diagnosis and treatment of various respiratory diseases.However,current anesthesia methods,such as spray,nebulized inhalation,and cricothyroid membrane puncture,have their own advantages and disadvantages.Recently,studies have shown that bronchoscopic direct-view glottis anesthesia is a simple and inexpensive method that shortens the examination time and provides excellent anesthetic results.AIM To evaluate the effectiveness of bronchoscopic direct vision glottis anesthesia for bronchoscopy.METHODS The study included 100 patients who underwent bronchoscopy during thoracic surgery.A random number table method was used to divide the patients into control and observation groups(50 patients each).The control and observation groups were anesthetized using the nebulized inhalation and bronchoscopic direct vision glottis method,respectively.Hemodynamic indices[systolic blood pressure(SBP),diastolic blood pressure(DBP),heart rate(HR),and oxygen saturation(SpO_(2))before(T1),5 min after anesthesia(T2),and at the end of the operation(T3)]serum stress hormone indices[norepinephrine(NE),epinephrine(E),adrenocorticotropic hormone(ACTH),and cortisol(Cor)before and after treatment]were compared between the 2 groups.Adverse effects were also RESULTS At T2 and T3,SBP,DBP,and HR were lower in the observation group than the control group,whereas SpO_(2) was higher than the control group[(119.05±8.01)mmHg vs(127.05±7.83)mmHg,(119.35±6.66)mmHg vs(128.39±6.56)mmHg,(84.68±6.04)mmHg vs(92.42±5.57)mmHg,(84.53±4.97)mmHg compared to(92.57±6.02)mmHg,(74.25±5.18)beats/min compared to(88.32±5.72)beats/min,(74.38±5.31)beats/min compared to(88.42±5.69)beats/min,(97.36±2.21)%vs(94.35±2.16)%,(97.42±2.36)%vs(94.38±2.69%],with statistically significant differences(all P<0.05).After treatment,NE,E,ACTH,and Cor were significantly higher in both groups than before treatment,but were lower in the observation group than in the control group[(68.25±8.87)ng/mL vs(93.35±14.00)ng/mL,(53.59±5.89)ng/mL vs(82.32±10.70)ng/mL,(14.32±1.58)pg/mL vs(20.35±3.05)pg/mL,(227.35±25.01)nmol/L vs(322.28±45.12)nmol/L],with statistically significant differences(all P<0.05).The incidence of adverse reactions was higher in the control group than in the observation group[12.00%(12/50)vs 6.00%(3/50)](P<0.05).CONCLUSION The use of bronchoscopic direct vision glottis anesthesia method for bronchoscopy patients is beneficial for stabilizing hemodynamic indices during bronchoscopy and reducing the level of patient stress,with good safety and practicality.展开更多
AIM: To illustrate the isoform-specific role and mechanism of c-Jun N-terminal kinases(JNKs) in mouse optic nerve axotomy induced neurotrauma. METHODS: We firstly investigated the expression of JNK1, JNK2, and JNK3 in...AIM: To illustrate the isoform-specific role and mechanism of c-Jun N-terminal kinases(JNKs) in mouse optic nerve axotomy induced neurotrauma. METHODS: We firstly investigated the expression of JNK1, JNK2, and JNK3 in the retinal ganglion cells(RGCs) by double-immunofluorescent staining. Then we created optic nerve axotomy model in wild type as well as JNK1, JNK2, JNK3, isoform specific gene deficiency mice. With that, we checked the protein expression profile of JNKs and its active form, and quantified the survival RGCs number by immunofluorescence staining. We further explored the molecules underlying isoform specific protective effect by real-time polymerase chain reaction(PCR) and Western blotting assay. RESULTS: We found that all the three isoforms of JNKs were expressed in the RGCs. Deficiency of JNK3, but not JNK1 or JNK2, significantly alleviated optic nerve axotomyinduced RGCs apoptosis. We further established that expression of Noxa, a pro-apoptotic member of BH3 family, was significantly suppressed only in JNK3 gene deficiency mice. But tumor necrosis factor receptor 1(TNFR1) and Fas, two key modulators of death receptor mediated apoptosis pathway, did not display obvious change in the expression. CONCLUSION: It is suggested that mitochondria mediated apoptosis, but not death receptor mediated apoptosis got involved in the JNK3 gene deficiency induced RGCs protection. Our study provides a novel insight into the isoform-specific role of JNKs in neurotrauma and indicates some cues for its therapeutics.展开更多
Fe-Mn-Co-xTa alloys(x=0,1,2,3 wt.%)were fabricated using spark plasma sintering to explore the influence of Ta content on the microstructure,mechanical properties,and damping characteristics of Fe-17Mn-3Co damping all...Fe-Mn-Co-xTa alloys(x=0,1,2,3 wt.%)were fabricated using spark plasma sintering to explore the influence of Ta content on the microstructure,mechanical properties,and damping characteristics of Fe-17Mn-3Co damping alloys.The micro structural analysis reveals the dominant presence ofγ-austenite,ε-martensite,α'-martensite,and Co_(3)Ta precipitates within the alloy.Incremental increments in Ta content exhibit proportional enhancements in hardness,tensile strength,and fracture elongation of the alloy.Notably,these improvements in mechanical attributes are closely correlated with the generated second-phase Co_(3)Ta.As the Ta content increases,there is a gradual augmentation in the formation of Co_(3)Ta within the alloy.Consequently,the damping property initially experiences an ascent followed by a subsequent decline with rising Ta content.This damping behavior finds its origins in multiple mechanisms,including grain boundary damping stemming from reduced grain size,interfacial damping induced by the generated Co_(3)Ta,and dislocation damping.It is noteworthy that the emergence of the secondary phase wields a dual impact on damping property.On the one hand,the proliferation of the second phase fosters increased interfaces for energy dissipation.On the other hand,these interfaces give rise to compressive stresses,constraining interface movement and thus impeding damping property enhancement.展开更多
Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in...Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in rare instances host switching can result in Ficus species sharing pollinators.in this study,we examined factors facilitating observed host switching at Xishuangbanna in southwestern(sW)China,where Ficus squamosa is at the northern edge of its range and lacks the fig wasps that pollinate it elsewhere,and its figs are colonized by a Ceratosolen pollinator that routinely breeds in figs of F.heterostyla.Methods We recorded the habitat preferences of F.squamosa and F.heterost-yla at Xishuangbanna,and compared characteristics such as fig size,location and colour at receptive phase.Furthermore,the vegetative and reproductive phenologies in the populations of F.squamosa and F.heterostyla were recorded weekly at Xishuangbanna Tropical botanical garden for 1 year.Important Findings Ficus squamosa is a shrub found near fast-flowing rivers,F.heterostyla is a small tree of disturbed forest edges.although preferring different habitats,they can be found growing close together.both species have figs located at or near ground level,but they differ in size when pollinated.Fig production in F.squamosa was concentrated in the colder months.F.heterostyla produced more figs in summer but had some through-out the year.The absence of its normal pollinators,in combination with similarly located figs and partially complementary fruiting patterns appear to have facilitated colonization of F.squamosa by the routine pollinator of F.heterostyla.The figs probably also share similar attractant volatiles.This host switching suggests one mechanism whereby fig trees can acquire new pollinators and emphasizes the likely significance of edges of ranges in the genesis of novel fig tree-fig wasp relationships.展开更多
We theoretically explore the manipulation of a temporal electron-spin splitter by aδ-potential in an embedded magnetic-elec tric-barrier micro structure(EMEBM),which is constructed by patterning a ferromagnetic strip...We theoretically explore the manipulation of a temporal electron-spin splitter by aδ-potential in an embedded magnetic-elec tric-barrier micro structure(EMEBM),which is constructed by patterning a ferromagnetic stripe and a Schottky-metal stripe on the top and bottom of an InAs/Al_(x)In_(1-x)As heterostructure,respectively.Spin polarization of the dwell time remains,even though aδ-potential is inserted by atomic-layer doping.Both the magnitude and sign of the spinpolarized dwell time can be manipulated by changing the weight or position of the 6-potential.Thus,a structurally controllable temporal electron-spin splitter can be obtained for spintronics device applications.展开更多
基金supported by National Nature Science Foundation of China(No.22075230)the financial support of the doctoral research foundation(No.19ZX7102)from Southwest University of Science and Technology。
文摘The properties of the combustion and deflagration to detonation transition(DDT)of Al/Fe_(2)O_(3)/RDX hybrid nanocomposites,a type of potentially novel lead-free primary explosives,were tested in weakly confined conditions,and the interaction of Al/Fe_(2)O_(3)nanothermite and RDX in the DDT process was studied in detail.Results show that the amount of the Al/Fe_(2)O_(3)nanothermite has a great effect on the DDT properties of Al/Fe_(2)O_(3)/RDX nanocomposites.The addition of Al/Fe_(2)O_(3)nanothermite to RDX apparently improves the firing properties of RDX.A small amount of Al/Fe_(2)O_(3)nanothermite greatly increases the initial combustion velocity of Al/Fe_(2)O_(3)/RDX nanocomposites,accelerating their DDT process.When the contents of Al/Fe_(2)O_(3)nanothermite are less than 20 wt%,the DDT mechanisms of Al/Fe_(2)O_(3)/RDX nanocomposites follow the distinct abrupt mode,and are consistent with that of RDX,though their DDT processes are different.The RDX added into the Al/Fe_(2)O_(3)nanothermite increases the latter's peak combustion velocity and makes it generate the DDT when the RDX content is at least 10 wt%.RDX plays a key role in the shock compressive combustion,the formation and the properties of the DDT in the flame propagation of nanocomposites.Compared with RDX,the fast DDT of Al/Fe_(2)O_(3)/RDX nanocomposites could be obtained by adjusting the chemical constituents of nanocomposites.
基金Hebei Science and Technology Program,No.162777232(to Xing SS).
文摘BACKGROUND Fibrobronchoscopy is a common adjunct tool that requires anesthesia and is widely used in the diagnosis and treatment of various respiratory diseases.However,current anesthesia methods,such as spray,nebulized inhalation,and cricothyroid membrane puncture,have their own advantages and disadvantages.Recently,studies have shown that bronchoscopic direct-view glottis anesthesia is a simple and inexpensive method that shortens the examination time and provides excellent anesthetic results.AIM To evaluate the effectiveness of bronchoscopic direct vision glottis anesthesia for bronchoscopy.METHODS The study included 100 patients who underwent bronchoscopy during thoracic surgery.A random number table method was used to divide the patients into control and observation groups(50 patients each).The control and observation groups were anesthetized using the nebulized inhalation and bronchoscopic direct vision glottis method,respectively.Hemodynamic indices[systolic blood pressure(SBP),diastolic blood pressure(DBP),heart rate(HR),and oxygen saturation(SpO_(2))before(T1),5 min after anesthesia(T2),and at the end of the operation(T3)]serum stress hormone indices[norepinephrine(NE),epinephrine(E),adrenocorticotropic hormone(ACTH),and cortisol(Cor)before and after treatment]were compared between the 2 groups.Adverse effects were also RESULTS At T2 and T3,SBP,DBP,and HR were lower in the observation group than the control group,whereas SpO_(2) was higher than the control group[(119.05±8.01)mmHg vs(127.05±7.83)mmHg,(119.35±6.66)mmHg vs(128.39±6.56)mmHg,(84.68±6.04)mmHg vs(92.42±5.57)mmHg,(84.53±4.97)mmHg compared to(92.57±6.02)mmHg,(74.25±5.18)beats/min compared to(88.32±5.72)beats/min,(74.38±5.31)beats/min compared to(88.42±5.69)beats/min,(97.36±2.21)%vs(94.35±2.16)%,(97.42±2.36)%vs(94.38±2.69%],with statistically significant differences(all P<0.05).After treatment,NE,E,ACTH,and Cor were significantly higher in both groups than before treatment,but were lower in the observation group than in the control group[(68.25±8.87)ng/mL vs(93.35±14.00)ng/mL,(53.59±5.89)ng/mL vs(82.32±10.70)ng/mL,(14.32±1.58)pg/mL vs(20.35±3.05)pg/mL,(227.35±25.01)nmol/L vs(322.28±45.12)nmol/L],with statistically significant differences(all P<0.05).The incidence of adverse reactions was higher in the control group than in the observation group[12.00%(12/50)vs 6.00%(3/50)](P<0.05).CONCLUSION The use of bronchoscopic direct vision glottis anesthesia method for bronchoscopy patients is beneficial for stabilizing hemodynamic indices during bronchoscopy and reducing the level of patient stress,with good safety and practicality.
文摘AIM: To illustrate the isoform-specific role and mechanism of c-Jun N-terminal kinases(JNKs) in mouse optic nerve axotomy induced neurotrauma. METHODS: We firstly investigated the expression of JNK1, JNK2, and JNK3 in the retinal ganglion cells(RGCs) by double-immunofluorescent staining. Then we created optic nerve axotomy model in wild type as well as JNK1, JNK2, JNK3, isoform specific gene deficiency mice. With that, we checked the protein expression profile of JNKs and its active form, and quantified the survival RGCs number by immunofluorescence staining. We further explored the molecules underlying isoform specific protective effect by real-time polymerase chain reaction(PCR) and Western blotting assay. RESULTS: We found that all the three isoforms of JNKs were expressed in the RGCs. Deficiency of JNK3, but not JNK1 or JNK2, significantly alleviated optic nerve axotomyinduced RGCs apoptosis. We further established that expression of Noxa, a pro-apoptotic member of BH3 family, was significantly suppressed only in JNK3 gene deficiency mice. But tumor necrosis factor receptor 1(TNFR1) and Fas, two key modulators of death receptor mediated apoptosis pathway, did not display obvious change in the expression. CONCLUSION: It is suggested that mitochondria mediated apoptosis, but not death receptor mediated apoptosis got involved in the JNK3 gene deficiency induced RGCs protection. Our study provides a novel insight into the isoform-specific role of JNKs in neurotrauma and indicates some cues for its therapeutics.
基金supported by the Key Labora tory of Infrared Imaging Materials and Detectors,Shanghai Insti tute of Technical Physics,Chinese Academy of Sciences(No.IIM DKFJJ-21-10)China Postdoctoral Science Foundation(No 2018T110993)。
文摘Fe-Mn-Co-xTa alloys(x=0,1,2,3 wt.%)were fabricated using spark plasma sintering to explore the influence of Ta content on the microstructure,mechanical properties,and damping characteristics of Fe-17Mn-3Co damping alloys.The micro structural analysis reveals the dominant presence ofγ-austenite,ε-martensite,α'-martensite,and Co_(3)Ta precipitates within the alloy.Incremental increments in Ta content exhibit proportional enhancements in hardness,tensile strength,and fracture elongation of the alloy.Notably,these improvements in mechanical attributes are closely correlated with the generated second-phase Co_(3)Ta.As the Ta content increases,there is a gradual augmentation in the formation of Co_(3)Ta within the alloy.Consequently,the damping property initially experiences an ascent followed by a subsequent decline with rising Ta content.This damping behavior finds its origins in multiple mechanisms,including grain boundary damping stemming from reduced grain size,interfacial damping induced by the generated Co_(3)Ta,and dislocation damping.It is noteworthy that the emergence of the secondary phase wields a dual impact on damping property.On the one hand,the proliferation of the second phase fosters increased interfaces for energy dissipation.On the other hand,these interfaces give rise to compressive stresses,constraining interface movement and thus impeding damping property enhancement.
基金The Chinese Natural Science Foundation(31372253,31120002)the Young and Middle Aged Academic Leaders of Yunnan Province(2011HB041)the CAS 135 program(XTBG-T01,XTBG-T01,F01).
文摘Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in rare instances host switching can result in Ficus species sharing pollinators.in this study,we examined factors facilitating observed host switching at Xishuangbanna in southwestern(sW)China,where Ficus squamosa is at the northern edge of its range and lacks the fig wasps that pollinate it elsewhere,and its figs are colonized by a Ceratosolen pollinator that routinely breeds in figs of F.heterostyla.Methods We recorded the habitat preferences of F.squamosa and F.heterost-yla at Xishuangbanna,and compared characteristics such as fig size,location and colour at receptive phase.Furthermore,the vegetative and reproductive phenologies in the populations of F.squamosa and F.heterostyla were recorded weekly at Xishuangbanna Tropical botanical garden for 1 year.Important Findings Ficus squamosa is a shrub found near fast-flowing rivers,F.heterostyla is a small tree of disturbed forest edges.although preferring different habitats,they can be found growing close together.both species have figs located at or near ground level,but they differ in size when pollinated.Fig production in F.squamosa was concentrated in the colder months.F.heterostyla produced more figs in summer but had some through-out the year.The absence of its normal pollinators,in combination with similarly located figs and partially complementary fruiting patterns appear to have facilitated colonization of F.squamosa by the routine pollinator of F.heterostyla.The figs probably also share similar attractant volatiles.This host switching suggests one mechanism whereby fig trees can acquire new pollinators and emphasizes the likely significance of edges of ranges in the genesis of novel fig tree-fig wasp relationships.
基金supported by the Science and Technology Innovation Plan Project of Hunan Province in China(S2019JJQNJJ2177)the National Natural Science Foundation of China(11864009)。
文摘We theoretically explore the manipulation of a temporal electron-spin splitter by aδ-potential in an embedded magnetic-elec tric-barrier micro structure(EMEBM),which is constructed by patterning a ferromagnetic stripe and a Schottky-metal stripe on the top and bottom of an InAs/Al_(x)In_(1-x)As heterostructure,respectively.Spin polarization of the dwell time remains,even though aδ-potential is inserted by atomic-layer doping.Both the magnitude and sign of the spinpolarized dwell time can be manipulated by changing the weight or position of the 6-potential.Thus,a structurally controllable temporal electron-spin splitter can be obtained for spintronics device applications.
