Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional an...Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional and medicinal values.Previous metabolomics analyses have revealed that sand rice contains abundant flavonoid components,which are known for their wide applications in cosmetics,food,and pharmaceuticals.To optimize the use of flavonoids in sand rice,in this study,the response surface methodology(RSM)was selected to determine the optimal ultrasonic-assisted extraction(UAE)criteria for flavonoids extraction from the aerial part of sand rice firstly.Statistical analyses unveiled the optimum parameters for flavonoids extraction fromsand rice could be 62%of ethanol concentration,1:43 solid-toliquid ratio,160Wfor ultrasound power,and 52℃for extraction temperature with extraction time of 12 min.Under this condition,the experiment optimumtotal flavonoid yield could reach at 15.24 mg/g,which was correspond to the maximum predicted value of RSM with 15.22 mg/g.Subsequently,the antifungal efficacy of these extracts was evaluated against three common plant pathogenic fungi,showing a significant inhibitory effect with the highest rate of inhibition reaching 25.3%at a concentration of 4 mg/mL,underscoring its potential as a natural antimicrobial agent.This studywill not only provide a powerful method to extract flavonoids froma desert resource plant,but also pave the way for industrial development and application of the promising desert plants with high nutritional and medicinal values.展开更多
Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structu...Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structural rigidity and flexibility,ensuring material integrity during large deformations,and providing adequate load-bearing capacity and stability once deployed.Most research has focused on optimizing cutout size and shape,while topology optimization offers a broader design space.However,the anisotropic properties of woven composite laminates,complex failure criteria,and multi-performance optimization needs have limited the exploration of topology optimization in this field.This work derives the sensitivities of bending stiffness,critical buckling load,and the failure index of woven composite materials with respect to element density,and formulates both single-objective and multi-objective topology optimization models using a linear weighted aggregation approach.The developed method was integrated with the commercial finite element software ABAQUS via a Python script,allowing efficient application to cutout design in various DCTWS configurations to maximize bending stiffness and critical buckling load under material failure constraints.Optimization of a classical tubular hinge resulted in improvements of 107.7%in bending stiffness and 420.5%in critical buckling load compared to level-set topology optimization results reported in the literature,validating the effectiveness of the approach.To facilitate future research and encourage the broader adoption of topology optimization techniques in DCTWS design,the source code for this work is made publicly available via a Git Hub link:https://github.com/jinhao-ok1/Topo-for-DCTWS.git.展开更多
Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in therm...Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in thermal power plants,the measurement repeatability of LIBS needs to be further improved due to the difficulty in controlling the stability of the generated plasmas at present.In this paper,we propose a novel x-ray fluorescence(XRF) assisted LIBS method for high repeatability analysis of coal quality,which not only inherits the ability of LIBS to directly analyze organic elements such as C and H in coal,but also uses XRF to make up for the lack of stability of LIBS in determining other inorganic ash-forming elements.With the combination of elemental lines in LIBS and XRF spectra,the principal component analysis and the partial least squares are used to establish the prediction model and perform multi-elemental and proximate analysis of coal.Quantitative analysis results show that the relative standard deviation(RSD) of C is 0.15%,the RSDs of other elements are less than 4%,and the standard deviations of calorific value,ash content,sulfur content and volatile matter are 0.11 MJ kg,0.17%,0.79% and 0.41%respectively,indicating that the method has good repeatability in determination of coal quality.This work is helpful to accelerate the development of LIBS in the field of rapid measurement of coal entering the power plant and on-line monitoring of coal entering the furnace.展开更多
In the field of phylogenetic analyses, the rbcL gene encoded large subunit Ribulose-1,5-biphosphate carboxylase/oxygenase （Rubisco, EC4.1.1.39）, which plays a crucial role in the process of photosynthesis for most ...In the field of phylogenetic analyses, the rbcL gene encoded large subunit Ribulose-1,5-biphosphate carboxylase/oxygenase （Rubisco, EC4.1.1.39）, which plays a crucial role in the process of photosynthesis for most terrestrial plants, has been considered to be conserved; however, recent controversy regarding rbcL conservation has appeared since it was proposed to be under natural selection within all principal lineages of land plants. In this study, by examining the variation of DNA and protein sequences among 17 species in the family Tamaricaceae, three nonsynonymous mutations were identified to be under positive selection. The favored sites were located in the alph-helix domains of Rubisco, with decreased hydrophobicity and increased entropy, which could facilitate C〇 2 penetration into the active site of Rubisco. We also found that the expression level of rbcL in different genotypes of Reaumuria soongarica shifted in response to various stresses such as drought, temperature, salt, and light. This study not only sheds light on the functional/structural features of Rubisco in the evolution scenarios from 〇 3-like into C4 in Tamaricaceae but also provides useful information on directing genetic performance to enhance photosynthesis efficiency of desert plants for sustaining fragile desert ecosystems; fur-thermore, it promotes the ability to cope with desert aridification and global warming.展开更多
Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route ...Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route to forming high entropy alloy films(HEAFs),but controlled preparation remains challeng-ing.This work used magnetron sputtering through adjusting preparation parameters to prepare ZrNbTi-CrCu HEAFs,achieving a significant improvement in corrosion resistance and biocompatibility induced by the precipitation of Cu.According to the electrochemical corrosion test,without obvious corrosion pits on the surface of S2 after corrosion,a passivation film composed of bimetallic oxide CuCrO2 formed on the film surface,indicating that ZrNbTiCrCu HEAFs have remarkable corrosion resistance performance.In the cytocompatibility experiment,the cell viability of HEAFs reached over 95%due to the precipitation of Cu,suggesting their excellent biocompatibility.In addition,ZrNbTiCrCu HEAFs exhibit outstanding an-tibacterial ability,especially when the sputtering current is 0.6 A,and the in vitro antibacterial rate of the sample against Escherichia coli is close to 99%.展开更多
Deployable space structure technology is an approach used in building spacecraft,especially when realizing deployment and folding functions.Once in orbit,the structures are released from the fairing,deployed,and posit...Deployable space structure technology is an approach used in building spacecraft,especially when realizing deployment and folding functions.Once in orbit,the structures are released from the fairing,deployed,and positioned.With the development of communication,remote-sensing,and navigation satellites,space-deployable structures have become cutting-edge research topics in space science and technology.This paper summarizes the current research status and development trend of spacedeployable structures in China,including large space mesh antennas,space solar arrays,and deployable structures and mechanisms for deep-space exploration.Critical technologies of space-deployable structures are addressed from the perspectives of deployable mechanisms,cable-membrane form-finding,dynamic analysis,reliable environmental adaptability analysis,and validation.Finally,future technology developments and trends are elucidated in the fields of mesh antennas,solar arrays,deployable mechanisms,and on-orbit adjustment,assembly,and construction.展开更多
Background Follicular cysts contribute significantly to reproductive loss in high-yield dairy cows.This results from the death of follicular granulosa cells(GCs)caused by oxidative stress.Quercetin is known to have si...Background Follicular cysts contribute significantly to reproductive loss in high-yield dairy cows.This results from the death of follicular granulosa cells(GCs)caused by oxidative stress.Quercetin is known to have significant antioxidant and anti-apoptotic effects.However,the effect of quercetin on follicular cysts has yet been elucidated.Therefore,this study aimed to explore the anti-oxidant and anti-apoptosis effects and potential molecular mechanisms of quercetin in H_(2)O_(2)-induced primary cow GCs and 3-nitropropionic acid(3-NPA)-induced mouse model of oxidative stress and thus treat ovarian cysts in dairy cows.Results In this study,compared with estrus cows,cows with follicular cysts showed heightened levels of oxidative stress and increased follicular cell apoptosis,while autophagy levels were reduced.A model of oxidative stress was induced in vitro by H_(2)O_(2)and showed significant increases in apoptosis together with reduced autophagy.These effects were significantly ameliorated by quercetin.Effects similar to those of quercetin were observed after treatmeat of cells with the reactive oxygen species(RCS)inhibitor N-acetylcysteine(NAC).Further investigations using chloroquine(autophagy inhibito r)]rapamycin(autophagy activato r),selisistat(SIRT1 inhibito r),and compound C(AMPK inhibitor)showed that chloroquine counteracted the effects of quercetin on oxidative stress-induced apoptosis,while rapamycin had the same effect as quercetin.In addition,the SIRT1/AMPK pathway inhibitors antagonized quercetin-mediated mitigation of the effects of oxidative stress on increased apoptosis and reduced autophagy.Consistent with the results in vitro,in mouse ovarian oxidative stress model induced by 3-NPA,quercetin activated autophagy through the SIRT1/AMPK signaling pathway,while alleviating oxidative stress damage and inhibiting apoptosis in mouse ovaries.Conclusions These findings indicate that quercetin can inhibit apoptosis in GCs and restore ovarian function by activating autophagy through the SIRT1/ROS/AMPK signaling pathway,suggesting a new direction for the treatment of ovarian follicular cysts in high-yield dairy cows.展开更多
In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectra...In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectral signal enhancement is paramount.To aid researchers in identification of optimal signal enhancement conditions and more accurate interpretation of the underlying signal enhancement mechanisms,theoretical simulations of the spatiotemporal processes of coaxial DP-LIBS-induced plasma have been established in this work.Using a model based on laser ablation and two-dimensional axisymmetric fluid dynamics,plasma evolutions during aluminum–magnesium alloy laser ablation under single-pulse and coaxial dualpulse excitations have been simulated.The influences of factors,such as delay time,laser fluence,plasma temperature,and particle number density,on the DP-LIBS spectral signals are investigated.Under pulse intervals ranging from 50 to 1500 ns,the time evolutions of spectral line intensity,dual-pulse emission enhancement relative to the single-pulse results,laser irradiance,spatial distribution of plasma temperature and species number density,as well as laser irradiance shielded by plasma have been obtained.The study indicates that the main reason behind the radiation signal enhancement in coaxial DP-LIBS-induced plasma is attributed to the increased species number density and plasma temperature caused by the second laser,and it is inferred that the shielding effect of the plasma mainly occurs in the boundary layer of the stagnation point flow over the target surface.This research provides a theoretical basis for experimental research,parameter optimization,and signal enhancement tracing in DP-LIBS.展开更多
Unhealthy eating habits with sugar-rich and high-fat foods can bring nutritional imbalance and other chronic diseases. At present, there is an increasing demand in regulating human sub-health through functional foods....Unhealthy eating habits with sugar-rich and high-fat foods can bring nutritional imbalance and other chronic diseases. At present, there is an increasing demand in regulating human sub-health through functional foods. Agriophyllum squarrosum(L.) Moq., a pioneer plant native to sand dunes with ecological restoration function, is a traditional food plant of sand regions and Mongolian folk medicine. Numerous studies have confirmed that A. squarrosum seed, also called sand rice, has high nutritional value. However, the long-term health effects of eating sand rice remain unclear. To better explore and evaluate its long-term effects, hereby, ICR mice were fed with sand rice flour at different ratios(control, 60% and 95%) for 100 days. Results show that the growth and blood glucose level curve of these experimental mice were lower and more stable than that of the control. In addition, mice fed pure sand rice ingredient(95%) gained more stable body weight and blood glucose after 28 days, which revealed that sand rice is a food with comprehensive nutritional value and rarely negatively impacts the body growth performance. Our data also demonstrates that, the content of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C) provided the lowest level in the blood of mice with a diet of pure sand rice ingredient, 0.48, 4.14, 0.91, 3.03 mmol/L, respectively. Also, T-SOD and GSH-PX activity provided a high level in mice with pure sand rice gradient, which significantly increased by 36%(T-SOD)and 19%(GSH-PX) compared to the control. These results suggest that long term intake of the pure sand rice ingredients is more helpful for stabilizing blood lipid and improve antioxidant capacity and beneficial to people suffering from chronic disease. This study supplies the first animal evidence to support the claim that sand rice is a promising functional food with comprehensive nutrition in the future. We are confident that, with increasing demands of daily sand rice usage, planting A. squarrosum in the vast desert regions will further increase the local economy and ecological restoration when coping with global warming.展开更多
Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems...Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems.The CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in orbit.This work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among them.The coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the literature.Then,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free deployment.The effect of material property change during storage was also discussed through numerical experiments.展开更多
The self-absorption effect in laser-induced breakdown spectroscopy(LIBS)reduces the accuracy of quantitative measurement results.The self-absorption-free LIBS(SAF-LIBS)has been proved to directly capture the optically...The self-absorption effect in laser-induced breakdown spectroscopy(LIBS)reduces the accuracy of quantitative measurement results.The self-absorption-free LIBS(SAF-LIBS)has been proved to directly capture the optically thin plasma spectra by setting an appropriate exposure time.In this work,a novel SAF-LIBS technique with high repetition rate acousto-optic gating is developed,in which an acousto-optic modulator is used as the shutter to diffract the optically thin fluorescence,and a high repetition rate laser is used to produce quasi-continuous plasmas to enhance the integral spectral intensity,so that the CCD spectrometer can replace an intensified CCD(ICCD)and echelle spectrometer in SAF-LIBS.Experimental results show that the average absolute prediction error of aluminum is reduced to 0.18%,which is equivalent to that of traditional SAF-LIBS.This technique not only effectively shields continuous background radiation and broadened spectral lines in optically thick plasma,but also has advantages of miniaturization,low cost,convenience and reliability.展开更多
基金support received from the Lanzhou Youth Science and Technology Talent Innovation Project(Grant No.:2023-QN-140)National Natural Science Foundation of China(Grant Nos.:31901079,32171608,32271695 and 32201378)the Chinese Academy of Sciences Strategic Biological Resources Program(Grant No.:KFJ-BRP-007-015).
文摘Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional and medicinal values.Previous metabolomics analyses have revealed that sand rice contains abundant flavonoid components,which are known for their wide applications in cosmetics,food,and pharmaceuticals.To optimize the use of flavonoids in sand rice,in this study,the response surface methodology(RSM)was selected to determine the optimal ultrasonic-assisted extraction(UAE)criteria for flavonoids extraction from the aerial part of sand rice firstly.Statistical analyses unveiled the optimum parameters for flavonoids extraction fromsand rice could be 62%of ethanol concentration,1:43 solid-toliquid ratio,160Wfor ultrasound power,and 52℃for extraction temperature with extraction time of 12 min.Under this condition,the experiment optimumtotal flavonoid yield could reach at 15.24 mg/g,which was correspond to the maximum predicted value of RSM with 15.22 mg/g.Subsequently,the antifungal efficacy of these extracts was evaluated against three common plant pathogenic fungi,showing a significant inhibitory effect with the highest rate of inhibition reaching 25.3%at a concentration of 4 mg/mL,underscoring its potential as a natural antimicrobial agent.This studywill not only provide a powerful method to extract flavonoids froma desert resource plant,but also pave the way for industrial development and application of the promising desert plants with high nutritional and medicinal values.
基金supported by the National Natural Science Foundation of China(No.12202295)the International(Regional)Cooperation and Exchange Projects of the National Natural Science Foundation of China(No.W2421002)+2 种基金the Sichuan Science and Technology Program(No.2025ZNSFSC0845)Zhejiang Provincial Natural Science Foundation of China(No.ZCLZ24A0201)the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.GK249909299001-004)。
文摘Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structural rigidity and flexibility,ensuring material integrity during large deformations,and providing adequate load-bearing capacity and stability once deployed.Most research has focused on optimizing cutout size and shape,while topology optimization offers a broader design space.However,the anisotropic properties of woven composite laminates,complex failure criteria,and multi-performance optimization needs have limited the exploration of topology optimization in this field.This work derives the sensitivities of bending stiffness,critical buckling load,and the failure index of woven composite materials with respect to element density,and formulates both single-objective and multi-objective topology optimization models using a linear weighted aggregation approach.The developed method was integrated with the commercial finite element software ABAQUS via a Python script,allowing efficient application to cutout design in various DCTWS configurations to maximize bending stiffness and critical buckling load under material failure constraints.Optimization of a classical tubular hinge resulted in improvements of 107.7%in bending stiffness and 420.5%in critical buckling load compared to level-set topology optimization results reported in the literature,validating the effectiveness of the approach.To facilitate future research and encourage the broader adoption of topology optimization techniques in DCTWS design,the source code for this work is made publicly available via a Git Hub link:https://github.com/jinhao-ok1/Topo-for-DCTWS.git.
基金supported by National Energy R&D Center of Petroleum Refining Technology of China(RIPP,SINOPEC)National Key Research and Development Program of China(No.2017YFA0304203)+5 种基金Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(No.IRT_17R70)National Natural Science Foundation of China(Nos.61975103,61875108,61775125 and 11434007)Industrial Application Innovation Project(No.627010407)Scientific and Technological Innovation Project of Shanxi Gemeng US-China Clean Energy R&D Center Co.,Ltd111 Project(D18001)Fund for Shanxi‘1331KSC’。
文摘Although laser-induced breakdown spectroscopy(LIBS),as a fast on-line analysis technology,has great potential and competitiveness in the analysis of chemical composition and proximate analysis results of coal in thermal power plants,the measurement repeatability of LIBS needs to be further improved due to the difficulty in controlling the stability of the generated plasmas at present.In this paper,we propose a novel x-ray fluorescence(XRF) assisted LIBS method for high repeatability analysis of coal quality,which not only inherits the ability of LIBS to directly analyze organic elements such as C and H in coal,but also uses XRF to make up for the lack of stability of LIBS in determining other inorganic ash-forming elements.With the combination of elemental lines in LIBS and XRF spectra,the principal component analysis and the partial least squares are used to establish the prediction model and perform multi-elemental and proximate analysis of coal.Quantitative analysis results show that the relative standard deviation(RSD) of C is 0.15%,the RSDs of other elements are less than 4%,and the standard deviations of calorific value,ash content,sulfur content and volatile matter are 0.11 MJ kg,0.17%,0.79% and 0.41%respectively,indicating that the method has good repeatability in determination of coal quality.This work is helpful to accelerate the development of LIBS in the field of rapid measurement of coal entering the power plant and on-line monitoring of coal entering the furnace.
基金supported by the National Natural Science Foundation of China(NSFC,Grant Nos.31370395 and 31500266)the"One Hundred Talents"project of the Chinese Academy of Sciences(Grant No.29Y127E71)
文摘In the field of phylogenetic analyses, the rbcL gene encoded large subunit Ribulose-1,5-biphosphate carboxylase/oxygenase （Rubisco, EC4.1.1.39）, which plays a crucial role in the process of photosynthesis for most terrestrial plants, has been considered to be conserved; however, recent controversy regarding rbcL conservation has appeared since it was proposed to be under natural selection within all principal lineages of land plants. In this study, by examining the variation of DNA and protein sequences among 17 species in the family Tamaricaceae, three nonsynonymous mutations were identified to be under positive selection. The favored sites were located in the alph-helix domains of Rubisco, with decreased hydrophobicity and increased entropy, which could facilitate C〇 2 penetration into the active site of Rubisco. We also found that the expression level of rbcL in different genotypes of Reaumuria soongarica shifted in response to various stresses such as drought, temperature, salt, and light. This study not only sheds light on the functional/structural features of Rubisco in the evolution scenarios from 〇 3-like into C4 in Tamaricaceae but also provides useful information on directing genetic performance to enhance photosynthesis efficiency of desert plants for sustaining fragile desert ecosystems; fur-thermore, it promotes the ability to cope with desert aridification and global warming.
基金the Natural Science Foundation of China(Nos.52205218,52401297)Natural Science Foundation of Shan-dong Province,China(Nos.ZR2020QE024 andZR2021QB015)the Youth Innovation Team Project of Higher Education Institutions in Shandong Province(No.2022KJ272).
文摘Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route to forming high entropy alloy films(HEAFs),but controlled preparation remains challeng-ing.This work used magnetron sputtering through adjusting preparation parameters to prepare ZrNbTi-CrCu HEAFs,achieving a significant improvement in corrosion resistance and biocompatibility induced by the precipitation of Cu.According to the electrochemical corrosion test,without obvious corrosion pits on the surface of S2 after corrosion,a passivation film composed of bimetallic oxide CuCrO2 formed on the film surface,indicating that ZrNbTiCrCu HEAFs have remarkable corrosion resistance performance.In the cytocompatibility experiment,the cell viability of HEAFs reached over 95%due to the precipitation of Cu,suggesting their excellent biocompatibility.In addition,ZrNbTiCrCu HEAFs exhibit outstanding an-tibacterial ability,especially when the sputtering current is 0.6 A,and the in vitro antibacterial rate of the sample against Escherichia coli is close to 99%.
基金financial support from the National Natural Science Foundation of China(11290154 and U20B2033)。
文摘Deployable space structure technology is an approach used in building spacecraft,especially when realizing deployment and folding functions.Once in orbit,the structures are released from the fairing,deployed,and positioned.With the development of communication,remote-sensing,and navigation satellites,space-deployable structures have become cutting-edge research topics in space science and technology.This paper summarizes the current research status and development trend of spacedeployable structures in China,including large space mesh antennas,space solar arrays,and deployable structures and mechanisms for deep-space exploration.Critical technologies of space-deployable structures are addressed from the perspectives of deployable mechanisms,cable-membrane form-finding,dynamic analysis,reliable environmental adaptability analysis,and validation.Finally,future technology developments and trends are elucidated in the fields of mesh antennas,solar arrays,deployable mechanisms,and on-orbit adjustment,assembly,and construction.
基金supported by the Science and Technology Department of Gansu Province(21JR7RA858)the National Natural Science Foundation of China(32160858)+2 种基金Gansu Youth Science and Technology Fund Program(21JR7RA843)the Beijing University of Agriculture Youth Science Innovation Ability Improvement Project(QJKC2022007)Research Project of Guangdong Vocational College of Science and Trade(GDKM2022-96)。
文摘Background Follicular cysts contribute significantly to reproductive loss in high-yield dairy cows.This results from the death of follicular granulosa cells(GCs)caused by oxidative stress.Quercetin is known to have significant antioxidant and anti-apoptotic effects.However,the effect of quercetin on follicular cysts has yet been elucidated.Therefore,this study aimed to explore the anti-oxidant and anti-apoptosis effects and potential molecular mechanisms of quercetin in H_(2)O_(2)-induced primary cow GCs and 3-nitropropionic acid(3-NPA)-induced mouse model of oxidative stress and thus treat ovarian cysts in dairy cows.Results In this study,compared with estrus cows,cows with follicular cysts showed heightened levels of oxidative stress and increased follicular cell apoptosis,while autophagy levels were reduced.A model of oxidative stress was induced in vitro by H_(2)O_(2)and showed significant increases in apoptosis together with reduced autophagy.These effects were significantly ameliorated by quercetin.Effects similar to those of quercetin were observed after treatmeat of cells with the reactive oxygen species(RCS)inhibitor N-acetylcysteine(NAC).Further investigations using chloroquine(autophagy inhibito r)]rapamycin(autophagy activato r),selisistat(SIRT1 inhibito r),and compound C(AMPK inhibitor)showed that chloroquine counteracted the effects of quercetin on oxidative stress-induced apoptosis,while rapamycin had the same effect as quercetin.In addition,the SIRT1/AMPK pathway inhibitors antagonized quercetin-mediated mitigation of the effects of oxidative stress on increased apoptosis and reduced autophagy.Consistent with the results in vitro,in mouse ovarian oxidative stress model induced by 3-NPA,quercetin activated autophagy through the SIRT1/AMPK signaling pathway,while alleviating oxidative stress damage and inhibiting apoptosis in mouse ovaries.Conclusions These findings indicate that quercetin can inhibit apoptosis in GCs and restore ovarian function by activating autophagy through the SIRT1/ROS/AMPK signaling pathway,suggesting a new direction for the treatment of ovarian follicular cysts in high-yield dairy cows.
基金supported by the National Key R&D Program of China (No. 2017YFA0304203)the National Energy R&D Center of Petroleum Refining Technology (RIPP, SINOPEC)+3 种基金Changjiang Scholars and Innovative Research Team at the University of the Ministry of Education of China (No. IRT_17R70)National Natural Science Foundation of China (NSFC) (Nos. 61975103, 61875108 and 627010407)111 Project (No. D18001)Fund for Shanxi (No. 1331KSC)
文摘In the field of dual-pulse laser-induced breakdown spectroscopy(DP-LIBS)research,the pursuit of methods for determining pulse intervals and other parameters quickly and conveniently in order to achieve optimal spectral signal enhancement is paramount.To aid researchers in identification of optimal signal enhancement conditions and more accurate interpretation of the underlying signal enhancement mechanisms,theoretical simulations of the spatiotemporal processes of coaxial DP-LIBS-induced plasma have been established in this work.Using a model based on laser ablation and two-dimensional axisymmetric fluid dynamics,plasma evolutions during aluminum–magnesium alloy laser ablation under single-pulse and coaxial dualpulse excitations have been simulated.The influences of factors,such as delay time,laser fluence,plasma temperature,and particle number density,on the DP-LIBS spectral signals are investigated.Under pulse intervals ranging from 50 to 1500 ns,the time evolutions of spectral line intensity,dual-pulse emission enhancement relative to the single-pulse results,laser irradiance,spatial distribution of plasma temperature and species number density,as well as laser irradiance shielded by plasma have been obtained.The study indicates that the main reason behind the radiation signal enhancement in coaxial DP-LIBS-induced plasma is attributed to the increased species number density and plasma temperature caused by the second laser,and it is inferred that the shielding effect of the plasma mainly occurs in the boundary layer of the stagnation point flow over the target surface.This research provides a theoretical basis for experimental research,parameter optimization,and signal enhancement tracing in DP-LIBS.
基金financially supported by the Biological Resources Programme,Chinese Academy of Sciences (Grant No.KFJ-BRP-007-015)the National Natural Science Foundation of China (Grant No.31901079 and 32171608)+2 种基金Jiangsu Provincial Key Research and Development Program (Grant No.18YF1NA123)Key Laboratory of Highway Construction and Maintenance Technology in the Loess Region of Shanxi Transportation Research Institute (Grant No.BRZD 1809)Lanzhou Talent Innovation and Entrepreneurship Project (Grant No.2021-RC-76).
文摘Unhealthy eating habits with sugar-rich and high-fat foods can bring nutritional imbalance and other chronic diseases. At present, there is an increasing demand in regulating human sub-health through functional foods. Agriophyllum squarrosum(L.) Moq., a pioneer plant native to sand dunes with ecological restoration function, is a traditional food plant of sand regions and Mongolian folk medicine. Numerous studies have confirmed that A. squarrosum seed, also called sand rice, has high nutritional value. However, the long-term health effects of eating sand rice remain unclear. To better explore and evaluate its long-term effects, hereby, ICR mice were fed with sand rice flour at different ratios(control, 60% and 95%) for 100 days. Results show that the growth and blood glucose level curve of these experimental mice were lower and more stable than that of the control. In addition, mice fed pure sand rice ingredient(95%) gained more stable body weight and blood glucose after 28 days, which revealed that sand rice is a food with comprehensive nutritional value and rarely negatively impacts the body growth performance. Our data also demonstrates that, the content of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C) provided the lowest level in the blood of mice with a diet of pure sand rice ingredient, 0.48, 4.14, 0.91, 3.03 mmol/L, respectively. Also, T-SOD and GSH-PX activity provided a high level in mice with pure sand rice gradient, which significantly increased by 36%(T-SOD)and 19%(GSH-PX) compared to the control. These results suggest that long term intake of the pure sand rice ingredients is more helpful for stabilizing blood lipid and improve antioxidant capacity and beneficial to people suffering from chronic disease. This study supplies the first animal evidence to support the claim that sand rice is a promising functional food with comprehensive nutrition in the future. We are confident that, with increasing demands of daily sand rice usage, planting A. squarrosum in the vast desert regions will further increase the local economy and ecological restoration when coping with global warming.
基金co-supported by the National Natural Science Foundation of China(No.12202295)the Fundamental Research Funds for the Central Universities,China(No.YJ2021137)+1 种基金the Open Project of State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi’an Jiaotong University,China(No.SV2021-KF-04)the Open Project of State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,China(No.GZ22120)。
文摘Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems.The CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in orbit.This work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among them.The coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the literature.Then,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free deployment.The effect of material property change during storage was also discussed through numerical experiments.
基金National Key R&D Program of China(No.2017YFA0304203)National Energy R&D Center of Petroleum Refining Technology(RIPP,SINOPEC),Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(IRT_17R70)+3 种基金National Natural Science Foundation of China(Nos.61975103,61875108,61775125 and 11434007)Major Special Science and Technology Projects in Shanxi(No.201804D131036)111 Project(No.D18001)Fund for Shanxi’1331KSC’。
文摘The self-absorption effect in laser-induced breakdown spectroscopy(LIBS)reduces the accuracy of quantitative measurement results.The self-absorption-free LIBS(SAF-LIBS)has been proved to directly capture the optically thin plasma spectra by setting an appropriate exposure time.In this work,a novel SAF-LIBS technique with high repetition rate acousto-optic gating is developed,in which an acousto-optic modulator is used as the shutter to diffract the optically thin fluorescence,and a high repetition rate laser is used to produce quasi-continuous plasmas to enhance the integral spectral intensity,so that the CCD spectrometer can replace an intensified CCD(ICCD)and echelle spectrometer in SAF-LIBS.Experimental results show that the average absolute prediction error of aluminum is reduced to 0.18%,which is equivalent to that of traditional SAF-LIBS.This technique not only effectively shields continuous background radiation and broadened spectral lines in optically thick plasma,but also has advantages of miniaturization,low cost,convenience and reliability.
