In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ...In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.展开更多
This paper reports the preparation of yttrium oxide(Y_(2)O_(3))doped with various concentrations of Er^(3+)using high temperature synthesis method.Photoluminescence(PL)emission spectra of the samples were recorded at ...This paper reports the preparation of yttrium oxide(Y_(2)O_(3))doped with various concentrations of Er^(3+)using high temperature synthesis method.Photoluminescence(PL)emission spectra of the samples were recorded at an excitation of 980 nm laser source.Two prominent peaks centered at 484 nm and 574 nm were found and attributed to the^(2)P3/2→^(4)I_(11/2)and^(4)S_(3/2)→^(4)I_(15/2),respectively.The sample with 2.5 mol%of Er^(3+)provided the optimum intensity in emission spectra.The sample with optimum PL emission was investigated for its thermoluminescence(TL)glow curve exhibited the second order kinetics.The peak TL intensity was found around 236°C,i.e.,towards high temperature which supports the fact of formation of deeper traps.Therefore,the material taken may be regarded as a good candidate for light emitting diode(LED)applications.展开更多
This article attempts to trace the status and many manifestations of erōs in Xenophon’s ethical and political thought.It examines its meaning in the narrow sense of“love and desire”and the broad sense of“affectiv...This article attempts to trace the status and many manifestations of erōs in Xenophon’s ethical and political thought.It examines its meaning in the narrow sense of“love and desire”and the broad sense of“affective feelings and friendship in the life of the family and the polis.”The principal goal is to demonstrate the remarkable coherence of Xenophon’s concept of erōs despite the diversity of the types of manifestation and visible differences in framing between male-male and male-female relationships.In addition,it will be shown that the principle of self-mastery as a vital criterion for the evaluation of sexual conduct is subordinated to what Xenophon perceives as the primary purpose of sexual intercourse:the procreation of progeny.展开更多
4-Nonylphenol(NP)is a kind of estrogen belonging to the endocrine disrupter,widely used in various agricultural and industrial goods.However,extensive use of NP with direct release to environment poses high risks to b...4-Nonylphenol(NP)is a kind of estrogen belonging to the endocrine disrupter,widely used in various agricultural and industrial goods.However,extensive use of NP with direct release to environment poses high risks to both human health and ecosystems.Herein,for the first time,we developed near-infrared(NIR)responsive upconversion luminescence nanosensor for NP detection.The Förster resonance energy transfer based upconversion nanoparticles(UCNPs)-graphene oxide sensor offers highly selective and sensitive detection of NP in linear ranges of 5−200 ng/mL and 200−1000 ng/mL under 980 nm and 808 nm excitation,respectively,with LOD at 4.2 ng/mL.The sensors were successfully tested for NP detection in real liquid milk samples with excellent recovery results.The rare-earth fluoride based upconversion luminescence nanosensor with NIR excitation wavelength,holds promise for sensing food,environmental,and biological samples due to their high sensitivity,specific recognition,low LOD,negligible autofluorescence,along with the deep penetration of NIR excitation sources.展开更多
The effectiveness of cranial suture expansion therapy hinges on the timely and adequate regeneration of bone tissue in response to mechanical stimuli.To optimize clinical outcomes and prevent post-expansion relapse,we...The effectiveness of cranial suture expansion therapy hinges on the timely and adequate regeneration of bone tissue in response to mechanical stimuli.To optimize clinical outcomes and prevent post-expansion relapse,we delved into the underlying mechanisms governing bone remodeling during the processes of suture expansion and relapse.Our findings revealed that in vitro stretching bolstered mesenchymal stem cells'antioxidative and osteogenic capacity by orchestrating mitochondrial activities,which governed by force-induced endoplasmic reticulum(ER)stress.Nonetheless,this signal transduction occurred through the activation of protein kinase R-like ER kinase(PERK)at the ER-mitochondria interface,rather than ER-mitochondria calcium flow as previously reported.Subsequently,PERK activation triggered TFEB translocation to the nucleus,thus regulating mitochondrial dynamics transcriptionally.Assessment of the mitochondrial pool during expansion and relapse unveiled a sequential,two-phase regulation governed by the ER stress/p-PERK/TFEB signaling cascade.Initially,PERK activation facilitated TFEB nuclear localization,stimulating mitochondrial biogenesis through PGC1-α,thereby addressing energy demands during the initial phase.Subsequently,TFEB shifted focus towards ensuring adequate mitophagy for mitochondrial quality maintenance during the remodeling process.Premature withdrawal of expanding force disrupted this sequential regulation,leading to compromised mitophagy and the accumulation of dysfunctional mitochondria,culminating in suboptimal bone regeneration and relapse.Notably,pharmacological activation of mitophagy effectively mitigated relapse and attenuated bone loss,while its inhibition impeded anticipated bone growth in remodeling progress.Conclusively,we elucidated the ER stress/p-PERK/TFEB signaling orchestrated sequential mitochondria biogenesis and mitophagy under mechanical stretch,thus ensuring antioxidative capacity and osteogenic potential of cranial suture tissues.展开更多
Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 n...Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors.展开更多
Bisphenol A(BPA)is an industrial pollutant that can cause immune impairment.Selenium acts as an antioxidant,as selenium deficiency often accompanies oxidative stress,resulting in organ damage.This study is the first t...Bisphenol A(BPA)is an industrial pollutant that can cause immune impairment.Selenium acts as an antioxidant,as selenium deficiency often accompanies oxidative stress,resulting in organ damage.This study is the first to demonstrate that BPA and/or selenium deficiency induce pyroptosis and ferroptosis-mediated thymic injury in chicken and chicken lymphoma cell(MDCC-MSB-1)via oxidative stress-induced endoplasmic reticulum(ER)stress.We established a broiler chicken model of BPA and/or selenium deficiency exposure and collected thymus samples as research subjects after 42 days.The results demonstrated that BPA or selenium deficiency led to a decrease in antioxidant enzyme activities(T-AOC,CAT,and GSH-Px),accumulation of peroxides(H2O2 and MDA),significant upregulation of ER stress-relatedmarkers(GRP78,IER 1,PERK,EIF-2α,ATF4,and CHOP),a significant increase in iron ion levels,significant upregulation of pyroptosis-related gene(NLRP3,ASC,Caspase1,GSDMD,IL-18 and IL-1β),significantly increase ferroptosis-related genes(TFRC,COX2)and downregulate GPX4,HO-1,FTH,NADPH.In vitro experiments conducted in MDCC-MSB-1 cells confirmed the results,demonstrating that the addition of antioxidant(NAC),ER stress inhibitor(TUDCA)and pyroptosis inhibitor(Vx765)alleviated oxidative stress,endoplasmic reticulum stress,pyroptosis,and ferroptosis.Overall,this study concludes that the combined effects of oxidative stress and ER stress mediate pyroptosis and ferroptosis in chicken thymus induced by BPA exposure and selenium deficiency.展开更多
Er-doped Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)magnets with a low remanence temperature coefficient were prepared by powder metallurgy method.The influence of Er content on the remanence and microstruct...Er-doped Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)magnets with a low remanence temperature coefficient were prepared by powder metallurgy method.The influence of Er content on the remanence and microstructure was investigated.X-ray diffractometer(XRD)analysis showed that the magnets with different Er contents consist of 2:17 R phase and 1:5 H phase.Scanning electron microscopy(SEM)analysis showed that the composition of the matrix is consistent with stoichiometric composition and no obvious precipitated phase appears.With the increase in doped Er amount,the temperature stability of Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)is getting better.When x is up to 0.3,the magnets with a low remanence temperature coefficient are obtained and the remanence descends tardily from 0.86 to 0.80 T as the temperature rises from room temperature to 400℃.These results indicate that Er substitution for Sm in SmCobased permanent magnets together with optimal composition and proper heat treatment could achieve a desired magnetic performance combined with high thermal stability.展开更多
基金supported by the Guangdong Basic and Applied Basic Research Foundation (No.2023A1515010093)the Shenzhen Fundamental Research Program (Stable Support Plan Program)(Nos.JCYJ20220809170611004, 20231121110828001 and 20231121113641002)the National Taipei University of Technology-Shenzhen University Joint Research Program (No.2024001)。
文摘In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.
文摘This paper reports the preparation of yttrium oxide(Y_(2)O_(3))doped with various concentrations of Er^(3+)using high temperature synthesis method.Photoluminescence(PL)emission spectra of the samples were recorded at an excitation of 980 nm laser source.Two prominent peaks centered at 484 nm and 574 nm were found and attributed to the^(2)P3/2→^(4)I_(11/2)and^(4)S_(3/2)→^(4)I_(15/2),respectively.The sample with 2.5 mol%of Er^(3+)provided the optimum intensity in emission spectra.The sample with optimum PL emission was investigated for its thermoluminescence(TL)glow curve exhibited the second order kinetics.The peak TL intensity was found around 236°C,i.e.,towards high temperature which supports the fact of formation of deeper traps.Therefore,the material taken may be regarded as a good candidate for light emitting diode(LED)applications.
文摘This article attempts to trace the status and many manifestations of erōs in Xenophon’s ethical and political thought.It examines its meaning in the narrow sense of“love and desire”and the broad sense of“affective feelings and friendship in the life of the family and the polis.”The principal goal is to demonstrate the remarkable coherence of Xenophon’s concept of erōs despite the diversity of the types of manifestation and visible differences in framing between male-male and male-female relationships.In addition,it will be shown that the principle of self-mastery as a vital criterion for the evaluation of sexual conduct is subordinated to what Xenophon perceives as the primary purpose of sexual intercourse:the procreation of progeny.
文摘4-Nonylphenol(NP)is a kind of estrogen belonging to the endocrine disrupter,widely used in various agricultural and industrial goods.However,extensive use of NP with direct release to environment poses high risks to both human health and ecosystems.Herein,for the first time,we developed near-infrared(NIR)responsive upconversion luminescence nanosensor for NP detection.The Förster resonance energy transfer based upconversion nanoparticles(UCNPs)-graphene oxide sensor offers highly selective and sensitive detection of NP in linear ranges of 5−200 ng/mL and 200−1000 ng/mL under 980 nm and 808 nm excitation,respectively,with LOD at 4.2 ng/mL.The sensors were successfully tested for NP detection in real liquid milk samples with excellent recovery results.The rare-earth fluoride based upconversion luminescence nanosensor with NIR excitation wavelength,holds promise for sensing food,environmental,and biological samples due to their high sensitivity,specific recognition,low LOD,negligible autofluorescence,along with the deep penetration of NIR excitation sources.
基金supported by National Natural Science Foundation of China(No.82370988,32271416,81870743,82170934)Sichuan Province Science and Technology Support Program(2024YFHZ0043)。
文摘The effectiveness of cranial suture expansion therapy hinges on the timely and adequate regeneration of bone tissue in response to mechanical stimuli.To optimize clinical outcomes and prevent post-expansion relapse,we delved into the underlying mechanisms governing bone remodeling during the processes of suture expansion and relapse.Our findings revealed that in vitro stretching bolstered mesenchymal stem cells'antioxidative and osteogenic capacity by orchestrating mitochondrial activities,which governed by force-induced endoplasmic reticulum(ER)stress.Nonetheless,this signal transduction occurred through the activation of protein kinase R-like ER kinase(PERK)at the ER-mitochondria interface,rather than ER-mitochondria calcium flow as previously reported.Subsequently,PERK activation triggered TFEB translocation to the nucleus,thus regulating mitochondrial dynamics transcriptionally.Assessment of the mitochondrial pool during expansion and relapse unveiled a sequential,two-phase regulation governed by the ER stress/p-PERK/TFEB signaling cascade.Initially,PERK activation facilitated TFEB nuclear localization,stimulating mitochondrial biogenesis through PGC1-α,thereby addressing energy demands during the initial phase.Subsequently,TFEB shifted focus towards ensuring adequate mitophagy for mitochondrial quality maintenance during the remodeling process.Premature withdrawal of expanding force disrupted this sequential regulation,leading to compromised mitophagy and the accumulation of dysfunctional mitochondria,culminating in suboptimal bone regeneration and relapse.Notably,pharmacological activation of mitophagy effectively mitigated relapse and attenuated bone loss,while its inhibition impeded anticipated bone growth in remodeling progress.Conclusively,we elucidated the ER stress/p-PERK/TFEB signaling orchestrated sequential mitochondria biogenesis and mitophagy under mechanical stretch,thus ensuring antioxidative capacity and osteogenic potential of cranial suture tissues.
基金Project supported by the Science and Technology International Cooperation Project of Qinghai Province (2022-HZ-807)the Open Project Salt Lake Chemical Engineering Research Complex,Qinghai University (2023-DXSSZZ-04)。
文摘Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors.
基金supported by the National Natural Science Foundation of China Regional Joint Innovation Fund (No.U22A20524)the Heilongjiang Province Natural Science Foundation Key projects (No.ZD2023C002).
文摘Bisphenol A(BPA)is an industrial pollutant that can cause immune impairment.Selenium acts as an antioxidant,as selenium deficiency often accompanies oxidative stress,resulting in organ damage.This study is the first to demonstrate that BPA and/or selenium deficiency induce pyroptosis and ferroptosis-mediated thymic injury in chicken and chicken lymphoma cell(MDCC-MSB-1)via oxidative stress-induced endoplasmic reticulum(ER)stress.We established a broiler chicken model of BPA and/or selenium deficiency exposure and collected thymus samples as research subjects after 42 days.The results demonstrated that BPA or selenium deficiency led to a decrease in antioxidant enzyme activities(T-AOC,CAT,and GSH-Px),accumulation of peroxides(H2O2 and MDA),significant upregulation of ER stress-relatedmarkers(GRP78,IER 1,PERK,EIF-2α,ATF4,and CHOP),a significant increase in iron ion levels,significant upregulation of pyroptosis-related gene(NLRP3,ASC,Caspase1,GSDMD,IL-18 and IL-1β),significantly increase ferroptosis-related genes(TFRC,COX2)and downregulate GPX4,HO-1,FTH,NADPH.In vitro experiments conducted in MDCC-MSB-1 cells confirmed the results,demonstrating that the addition of antioxidant(NAC),ER stress inhibitor(TUDCA)and pyroptosis inhibitor(Vx765)alleviated oxidative stress,endoplasmic reticulum stress,pyroptosis,and ferroptosis.Overall,this study concludes that the combined effects of oxidative stress and ER stress mediate pyroptosis and ferroptosis in chicken thymus induced by BPA exposure and selenium deficiency.
基金financially supported by the National Natural Science Foundation of China(Nos.51761145026 and 51471016)the Beijing Natural Science Foundation(No.2151002).
文摘Er-doped Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)magnets with a low remanence temperature coefficient were prepared by powder metallurgy method.The influence of Er content on the remanence and microstructure was investigated.X-ray diffractometer(XRD)analysis showed that the magnets with different Er contents consist of 2:17 R phase and 1:5 H phase.Scanning electron microscopy(SEM)analysis showed that the composition of the matrix is consistent with stoichiometric composition and no obvious precipitated phase appears.With the increase in doped Er amount,the temperature stability of Sm1-xErx(CobalFe0.15Cu0.08Zr0.03)7.8(x=0,0.1,0.2,0.3)is getting better.When x is up to 0.3,the magnets with a low remanence temperature coefficient are obtained and the remanence descends tardily from 0.86 to 0.80 T as the temperature rises from room temperature to 400℃.These results indicate that Er substitution for Sm in SmCobased permanent magnets together with optimal composition and proper heat treatment could achieve a desired magnetic performance combined with high thermal stability.