“Inf luenced by the slow recover y of the globa l economy,the continual impact of El Niño,growing local conflicts,the prevalence of trade protectionism and other factors,this year,the global supply and demand fo...“Inf luenced by the slow recover y of the globa l economy,the continual impact of El Niño,growing local conflicts,the prevalence of trade protectionism and other factors,this year,the global supply and demand for agricultural products and trade is under pressure,and the world’s food security has been a serious challenge.Therefore,it is of great and far-reaching significance for all countries in the world to further develop international cooperation in agriculture from a strategic height,in order to maintain the resilience of the international supply chain of agriculture,and to promote mutual benefits and the common development of all parties.”Yu Jianlong,Vice President of China Council for the Promotion of International Trade(CCPIT)and Vice President of the China Chamber of International Commerce(CCIC),said at the 2024 China Agricultural Conference for International Economic and Trade Cooperation.展开更多
Two recent trips to cities in China got me thinking a lot about China’s development and efforts to maintain its identity.While China is developing with strong momentum in every sector,it has succeeded at preserving a...Two recent trips to cities in China got me thinking a lot about China’s development and efforts to maintain its identity.While China is developing with strong momentum in every sector,it has succeeded at preserving and upholding its ancient traditions and customs.These trips showed me a country not only keen on technological and infrastructural advancement but also deeply committed to cultural preservation and promotion.In every corner of these cities,I witnessed a harmonious blend of the old and new,a testament to China’s dedication to maintaining its cultural heritage while embracing modernity.展开更多
Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE pr...Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE protein isoforms with cysteine and arginine substitutions at amino acid positions 112 and 158 that impact their lipidation and related functions(Flowers and Rebeck,2020).ApoE2 is characterized by Cys112 and Cys158,ApoE3 by Cys112 and Arg158,whereas ApoE4 contains Arg112 and Arg158.展开更多
Non-proliferating cells efficiently generate adenosine 5’-triphosphate (ATP) through mitochondrial oxidative phosphorylation.By contrast, proliferating cells, including cancer cells, tend to rely on aerobic glycolysi...Non-proliferating cells efficiently generate adenosine 5’-triphosphate (ATP) through mitochondrial oxidative phosphorylation.By contrast, proliferating cells, including cancer cells, tend to rely on aerobic glycolysis, an inefficient way to generate energy, and this phenomenon is termed 'the Warburg effect'1,2.However, the advantage of the Warburg effect provided for proliferating cells has been unclear3.Here we propose that aerobic glycolysis may maintain proton homeostasis to benefit proliferating cells.展开更多
Heat shock protein 70(HSP70) maintains Ca^2+ homeostasis in PC12 cells,which may protect against apoptosis;however,the mechanisms of neuroprotection are unclear.Therefore,in this study,we examined Ca^2+ levels in ...Heat shock protein 70(HSP70) maintains Ca^2+ homeostasis in PC12 cells,which may protect against apoptosis;however,the mechanisms of neuroprotection are unclear.Therefore,in this study,we examined Ca^2+ levels in PC12 cells transfected with an exogenous lentiviral HSP70 gene expression construct,and we subsequently subjected the cells to ischemia-hypoxia/reoxygenation injury.HSP70 overexpression increased neuronal viability and ATPase activity,and it decreased cellular reactive oxygen species levels and intracellular Ca^2+ concentration after hypoxia/reoxygenation.HSP70 overexpression enhanced the protein and m RNA expression levels of sarcoplasmic/endoplasmic reticulum Ca^2+-ATPase(SERCA),but it decreased the protein and m RNA levels of inositol 1,4,5-trisphosphate receptor(IP3R),thereby leading to decreased intracellular Ca^2+concentration after ischemia-hypoxia/reoxygenation.These results suggest that exogenous HSP70 protects against ischemia-hypoxia/reoxygenation injury,at least in part,by maintaining cellular Ca^2+ homeostasis,by upregulating SERCA expression and by downregulating IP_3 R expression.展开更多
A low-repetition-rate, all-polarization-maintaining(PM)-fiber sub-nanosecond oscillator is presented, which is simple and low-cost, composed of standard components. The ring cavity is elongated by 114-m-long standar...A low-repetition-rate, all-polarization-maintaining(PM)-fiber sub-nanosecond oscillator is presented, which is simple and low-cost, composed of standard components. The ring cavity is elongated by 114-m-long standard PM fiber, and passively mode-locked by a fiber pigtailed semiconductor saturable absorber. Linearly polarized pulses with 1.66 MHz repetition rate and 22 dB polarization extinction ratio are generated at a wavelength of 1030 nm, which is determined by an intracavity filter. In addition, to demonstrate that the oscillator is a good seed for high energy pulse generation, an all-fiber master oscillator power amplifier is built and amplified pulses with energy about 2 μJ are obtained.展开更多
Fibroblast growth factor 19 (FGF19) is a kind of gut-derived postprandial hormone. As an atypical member of the FGF family, FGF19 functions as an endocrine hormone except regulating cell growth and differentiation. ...Fibroblast growth factor 19 (FGF19) is a kind of gut-derived postprandial hormone. As an atypical member of the FGF family, FGF19 functions as an endocrine hormone except regulating cell growth and differentiation. FGF19 plays a key role in coordination of liver bile acid biosynthesis and gallbladder motility, and acts as a regulator of metabolic homeostasis, including strengthening insulin sensitivity, decreasing triglyceride concentration and reducing body weight.展开更多
Ischemic preconditioning elicited by a non-fatal brief occlusion of blood flow has been applied for an experimental therapeutic strategy against a subsequent fatal ischemic insult. In this study, we investigated the n...Ischemic preconditioning elicited by a non-fatal brief occlusion of blood flow has been applied for an experimental therapeutic strategy against a subsequent fatal ischemic insult. In this study, we investigated the neuroprotective effects of ischemic preconditioning(2-minute transient cerebral ischemia) on calbindin D28k immunoreactivity in the gerbil hippocampal CA1 area following a subsequent fatal transient ischemic insult(5-minute transient cerebral ischemia). A large number of pyramidal neurons in the hippocampal CA1 area died 4 days after 5-minute transient cerebral ischemia. Ischemic preconditioning reduced the death of pyramidal neurons in the hippocampal CA1 area. Calbindin D28k immunoreactivity was greatly attenuated at 2 days after 5-minute transient cerebral ischemia and it was hardly detected at 5 days post-ischemia. Ischemic preconditioning maintained calbindin D28 k immunoreactivity after transient cerebral ischemia. These findings suggest that ischemic preconditioning can attenuate transient cerebral ischemia-caused damage to the pyramidal neurons in the hippocampal CA1 area through maintaining calbindin D28k immunoreactivity.展开更多
Reliability analysis of the inspected and repaired structure requires dealing with a large number of complex random events. Considering many kinds of random factors, a probability of these random events existing possi...Reliability analysis of the inspected and repaired structure requires dealing with a large number of complex random events. Considering many kinds of random factors, a probability of these random events existing possibly in the inspection and repair process and reliability analysis methodologies are proposed. A systematic dynamic reliability model is given for structures in service under the scheduled inspection and repair.展开更多
In this paper,the temperature dependence of birefringence in polarization maintaining photonic crystal fibres(PMPCFs) is investigated theoretically and experimentally.Utilizing the structural parameters of the PM-PC...In this paper,the temperature dependence of birefringence in polarization maintaining photonic crystal fibres(PMPCFs) is investigated theoretically and experimentally.Utilizing the structural parameters of the PM-PCF samples in the experiment,two effects leading to the birefringence variation under different temperatures are analysed,which are the thermal expansion of silica material and the refractive index variation due to the temperature variation.The actual birefringence variation of the PM-PCF is the combination of the two effects,which is in the order of 10-9 K-1 for both fibre samples.Calculation results also show that the influence of refractive index variation is the dominant contribution,which determines the tendency of the fibre birefringence variation with varying temperature.Then,the birefringence beat lengths of the two fibre samples are measured under the temperature,which varies from -40℃ to 80℃.A traditional PANDA-type polarization maintaining fibre(PMF) is also measured in the same way for comparison.The experimental results indicate that the birefringence variation of the PM-PCF due to temperature variation is far smaller than that of the traditional PMF,which agrees with the theoretical analysis.The ultra-low temperature dependence of the birefringence in the PM-PCF has great potential applications in temperature-insensitive fibre interferometers,fibre sensors,and fibre gyroscopes.展开更多
The Social security system is a necessary part of market economic system, the social security fund is the basis of running a country social security system. However, the fund of social security of our country has many...The Social security system is a necessary part of market economic system, the social security fund is the basis of running a country social security system. However, the fund of social security of our country has many problems, such as investment channel phase contrast is still relatively narrow, the portfolio is not reasonable enough, external capital market is not perfect and so on.so the social security fund in our country is difficult to achieve effective and value. This article will start from the concept of sustainable development, and hope to find out the existing problems in the process of maintaining and increasing the value of social security funds through combing the basic elements of social security funds.展开更多
An improved type of elliptical jacket polarization maintaining fiber was developed by using a modified chemical vapor deposition method with special treatment. Different from conventional elliptical jacket, the shape ...An improved type of elliptical jacket polarization maintaining fiber was developed by using a modified chemical vapor deposition method with special treatment. Different from conventional elliptical jacket, the shape of the stress jacket was transmuted. The cross-section of fiber consists of 5 layers: substrate, outer cladding, stress jacket, inner cladding and core. The cross sectional component distribution was investigated by electron probe microscopy and energy dispersive spectrum. The finite element method was used to calculate the stress birefringence. Based on the analyses of the microstructure, the technological process is improved. The temperature cycling test of the fiber wound into gyroscope coils was performed. The results show that the fiber possesses superior performance at high and low temperatures compared with other fibers. The high homogeneity is achieved by well-controlled modified chemical vapor deposition process. A homogeneous length of 8 km fiber is obtained. With advantages in homogeneity and length, the fiber has great potential in applications such as fiber gyroscopes, fiber hydrophone and other optical fiber sensors.展开更多
Recently,according to CNPC instructions,CNPC’s overseas projects,such as NGCP project in Saudi Arabia,CPL’s project in Bangladesh,XDEC’s project,and BHDC No.5 Drilling Company’s project,have maintained stable oper...Recently,according to CNPC instructions,CNPC’s overseas projects,such as NGCP project in Saudi Arabia,CPL’s project in Bangladesh,XDEC’s project,and BHDC No.5 Drilling Company’s project,have maintained stable operations while fighting against the epidemic–COVID-19.展开更多
Based on the results of plasma experiments and research work done by Dawson and Jones, Trubnikov, Endean, and other researchers, three requirements for producing and maintaining plasma ball lightning have been found: ...Based on the results of plasma experiments and research work done by Dawson and Jones, Trubnikov, Endean, and other researchers, three requirements for producing and maintaining plasma ball lightning have been found: 1) rotation of plasma, 2) the density of charged particles nc > 3.15 × 10-10ω2,3) a stable confinement of plasma. In this model, the energy density of ball lightning ranged from 10-2 J / cm3 to 104 J/ cm3, the formation, shape, stability, energy, maintaining processes and other properties of ball lightning were explained reasonably.展开更多
Foreign language learning is a complex process and its success is determined by a variety of factors.The prime one ofthem is motivation,which,as everyone knows,could be controlled by external forces so as to be taken ...Foreign language learning is a complex process and its success is determined by a variety of factors.The prime one ofthem is motivation,which,as everyone knows,could be controlled by external forces so as to be taken advantage of.Motivationcould prompt the learner to have his own learning goals and let him finish his learning task autonomously.All of that shows the im-portance of maintaining learners’motivation.This paper will demonstrate not only the definition and the types of motivation,but al-so the methods that could be used to stimulate and maintain the motivation.展开更多
In today's society,obesity is the single most important risk factor for early disability and death,and the incidence of obesity is still at an alarming level.The central nervous system regulates energy intake and ...In today's society,obesity is the single most important risk factor for early disability and death,and the incidence of obesity is still at an alarming level.The central nervous system regulates energy intake and consumption in response to changes in the body's energy storage,thereby maintaining the body's continued obesity;fat cell-derived hormone leptin and its receptor(LEPR)are the key regulators of these systems.As in the case of insulin resistance,various mechanisms have been proposed(including feedback inhibition,inflammation,glial hyperplasia,and endoplasmic reticulum stress)to interfere with the action of leptin,hindering the system that controls the body's energy balance to promote or maintain obesity,although these are not clear.However,in ordinary obese patients,the LEPR signal may be increased(rather than impaired),indicating that any obesity-related defects in leptin action must be caused by lesions other than the original LEPR signal.展开更多
BRICS proves it still has a major role to play in the development of emerging economies The BRICS partnership has proven that it is more relevant today than it ever has been,given that the polarization and protectioni...BRICS proves it still has a major role to play in the development of emerging economies The BRICS partnership has proven that it is more relevant today than it ever has been,given that the polarization and protectionism of traditional global powers is at an all-time high.Experts believe that this trajectory has particularly展开更多
Bone formation is a highly energy-demanding process that can be impacted by metabolic disorders.Glucose has been considered the principal substrate for osteoblasts,although fatty acids are also important for osteoblas...Bone formation is a highly energy-demanding process that can be impacted by metabolic disorders.Glucose has been considered the principal substrate for osteoblasts,although fatty acids are also important for osteoblast function.Here,we report that osteoblasts can derive energy from endogenous fatty acids stored in lipid droplets via lipolysis and that this process is critical for bone formation.As such,we demonstrate that osteoblasts accumulate lipid droplets that are highly dynamic and provide the molecular mechanism by which they serve as a fuel source for energy generation during osteoblast maturation.Inhibiting cytoplasmic lipolysis leads to both an increase in lipid droplet size in osteoblasts and an impairment in osteoblast function.The fatty acids released by lipolysis from these lipid droplets become critical for cellular energy production as cellular energetics shifts towards oxidative phosphorylation during nutrient-depleted conditions.In vivo,conditional deletion of the ATGL-encoding gene Pnpla2 in osteoblast progenitor cells reduces cortical and trabecular bone parameters and alters skeletal lipid metabolism.Collectively,our data demonstrate that osteoblasts store fatty acids in the form of lipid droplets,which are released via lipolysis to support cellular bioenergetic status when nutrients are limited.Perturbations in this process result in impairment of bone formation,specifically reducing ATP production and overall osteoblast function.展开更多
After harvest,potato tubers undergo an important period of dormancy,which significantly impacts potato quality and seed vigor.StSN2 has been reported as a key gene for maintaining tuber dormancy;in this study,we explo...After harvest,potato tubers undergo an important period of dormancy,which significantly impacts potato quality and seed vigor.StSN2 has been reported as a key gene for maintaining tuber dormancy;in this study,we explored the molecular mechanism by which StSN2 maintains dormancy.StBIN2 was first identified as a candidate protein that interacts with StSN2 by co-immunoprecipitation/mass spectrometry,and both qPCR and enzyme activity experiments showed that StSN2 can promote the StBIN2 expression and activity.In addition,the interaction between StSN2 and StBIN2 was verified by yeast two-hybrid,luciferase complementation experiments and co-immunoprecipitation.Bioinformatics analysis and site-directed mutagenesis confirmed the critical role of cysteine residues of StBIN2 in its binding to StSN2.Similar to that of StSN2,overexpression of StBIN2 extended the dormancy of potato tuber.Interaction between StSN2 and StBIN2 increased the activity of the StBIN2 enzyme,inhibited the expression of StBZR1,and suppressed BR signaling.On the contrary,this interaction promoted the expression of StSnRK2.2/2.3/2.4/2.6 and StABI5,key genes of ABA signaling,and the phosphorylation of StSnRK2.3,thereby promoting ABA signaling.Altogether,our results indicate that StSN2 interacts with StBIN2 through key cysteine residues and StBIN2 maintains tuber dormancy by affecting ABA and BR signaling.Findings of this research offer new insights into the molecular mechanism by which StSN2 maintains potato tuber dormancy through interaction with StSIN2 and provide guidance for potato improvement.展开更多
文摘“Inf luenced by the slow recover y of the globa l economy,the continual impact of El Niño,growing local conflicts,the prevalence of trade protectionism and other factors,this year,the global supply and demand for agricultural products and trade is under pressure,and the world’s food security has been a serious challenge.Therefore,it is of great and far-reaching significance for all countries in the world to further develop international cooperation in agriculture from a strategic height,in order to maintain the resilience of the international supply chain of agriculture,and to promote mutual benefits and the common development of all parties.”Yu Jianlong,Vice President of China Council for the Promotion of International Trade(CCPIT)and Vice President of the China Chamber of International Commerce(CCIC),said at the 2024 China Agricultural Conference for International Economic and Trade Cooperation.
文摘Two recent trips to cities in China got me thinking a lot about China’s development and efforts to maintain its identity.While China is developing with strong momentum in every sector,it has succeeded at preserving and upholding its ancient traditions and customs.These trips showed me a country not only keen on technological and infrastructural advancement but also deeply committed to cultural preservation and promotion.In every corner of these cities,I witnessed a harmonious blend of the old and new,a testament to China’s dedication to maintaining its cultural heritage while embracing modernity.
基金supported by core funding provided by Temasek Life Sciences Laboratory(to CTO)。
文摘Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE protein isoforms with cysteine and arginine substitutions at amino acid positions 112 and 158 that impact their lipidation and related functions(Flowers and Rebeck,2020).ApoE2 is characterized by Cys112 and Cys158,ApoE3 by Cys112 and Arg158,whereas ApoE4 contains Arg112 and Arg158.
基金supported by National Natural Science Foundation of China (Grant No.81622037 and 81672762)Beijing Municipal Natural Science Foundation (Grant No.5194023)Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five–year Plan (Grant No.CIT&TCD20190333)
文摘Non-proliferating cells efficiently generate adenosine 5’-triphosphate (ATP) through mitochondrial oxidative phosphorylation.By contrast, proliferating cells, including cancer cells, tend to rely on aerobic glycolysis, an inefficient way to generate energy, and this phenomenon is termed 'the Warburg effect'1,2.However, the advantage of the Warburg effect provided for proliferating cells has been unclear3.Here we propose that aerobic glycolysis may maintain proton homeostasis to benefit proliferating cells.
基金supported by the National Natural Science Foundation of China,No.81571938 and 81501706the Natural Science Foundation of Shandong Province of China,No.Y2007C133
文摘Heat shock protein 70(HSP70) maintains Ca^2+ homeostasis in PC12 cells,which may protect against apoptosis;however,the mechanisms of neuroprotection are unclear.Therefore,in this study,we examined Ca^2+ levels in PC12 cells transfected with an exogenous lentiviral HSP70 gene expression construct,and we subsequently subjected the cells to ischemia-hypoxia/reoxygenation injury.HSP70 overexpression increased neuronal viability and ATPase activity,and it decreased cellular reactive oxygen species levels and intracellular Ca^2+ concentration after hypoxia/reoxygenation.HSP70 overexpression enhanced the protein and m RNA expression levels of sarcoplasmic/endoplasmic reticulum Ca^2+-ATPase(SERCA),but it decreased the protein and m RNA levels of inositol 1,4,5-trisphosphate receptor(IP3R),thereby leading to decreased intracellular Ca^2+concentration after ischemia-hypoxia/reoxygenation.These results suggest that exogenous HSP70 protects against ischemia-hypoxia/reoxygenation injury,at least in part,by maintaining cellular Ca^2+ homeostasis,by upregulating SERCA expression and by downregulating IP_3 R expression.
基金Project supported by the Initiative Research Program of State Key Laboratory of Precision Measurement Technology and Instruments,Chinathe National Natural Science Foundation of China(Grant No.51527901)
文摘A low-repetition-rate, all-polarization-maintaining(PM)-fiber sub-nanosecond oscillator is presented, which is simple and low-cost, composed of standard components. The ring cavity is elongated by 114-m-long standard PM fiber, and passively mode-locked by a fiber pigtailed semiconductor saturable absorber. Linearly polarized pulses with 1.66 MHz repetition rate and 22 dB polarization extinction ratio are generated at a wavelength of 1030 nm, which is determined by an intracavity filter. In addition, to demonstrate that the oscillator is a good seed for high energy pulse generation, an all-fiber master oscillator power amplifier is built and amplified pulses with energy about 2 μJ are obtained.
基金supported by the Major Program of the Shanghai Municipality for Basic Research(10JC1412400)the National Natural Science Foundation Major International(Regional)Joint Research Project(81220108006)
文摘Fibroblast growth factor 19 (FGF19) is a kind of gut-derived postprandial hormone. As an atypical member of the FGF family, FGF19 functions as an endocrine hormone except regulating cell growth and differentiation. FGF19 plays a key role in coordination of liver bile acid biosynthesis and gallbladder motility, and acts as a regulator of metabolic homeostasis, including strengthening insulin sensitivity, decreasing triglyceride concentration and reducing body weight.
基金supported by Hallym University Research Fund,2016(HRF-201605-012)Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2016R1A6A3A01011698)
文摘Ischemic preconditioning elicited by a non-fatal brief occlusion of blood flow has been applied for an experimental therapeutic strategy against a subsequent fatal ischemic insult. In this study, we investigated the neuroprotective effects of ischemic preconditioning(2-minute transient cerebral ischemia) on calbindin D28k immunoreactivity in the gerbil hippocampal CA1 area following a subsequent fatal transient ischemic insult(5-minute transient cerebral ischemia). A large number of pyramidal neurons in the hippocampal CA1 area died 4 days after 5-minute transient cerebral ischemia. Ischemic preconditioning reduced the death of pyramidal neurons in the hippocampal CA1 area. Calbindin D28k immunoreactivity was greatly attenuated at 2 days after 5-minute transient cerebral ischemia and it was hardly detected at 5 days post-ischemia. Ischemic preconditioning maintained calbindin D28 k immunoreactivity after transient cerebral ischemia. These findings suggest that ischemic preconditioning can attenuate transient cerebral ischemia-caused damage to the pyramidal neurons in the hippocampal CA1 area through maintaining calbindin D28k immunoreactivity.
文摘Reliability analysis of the inspected and repaired structure requires dealing with a large number of complex random events. Considering many kinds of random factors, a probability of these random events existing possibly in the inspection and repair process and reliability analysis methodologies are proposed. A systematic dynamic reliability model is given for structures in service under the scheduled inspection and repair.
文摘In this paper,the temperature dependence of birefringence in polarization maintaining photonic crystal fibres(PMPCFs) is investigated theoretically and experimentally.Utilizing the structural parameters of the PM-PCF samples in the experiment,two effects leading to the birefringence variation under different temperatures are analysed,which are the thermal expansion of silica material and the refractive index variation due to the temperature variation.The actual birefringence variation of the PM-PCF is the combination of the two effects,which is in the order of 10-9 K-1 for both fibre samples.Calculation results also show that the influence of refractive index variation is the dominant contribution,which determines the tendency of the fibre birefringence variation with varying temperature.Then,the birefringence beat lengths of the two fibre samples are measured under the temperature,which varies from -40℃ to 80℃.A traditional PANDA-type polarization maintaining fibre(PMF) is also measured in the same way for comparison.The experimental results indicate that the birefringence variation of the PM-PCF due to temperature variation is far smaller than that of the traditional PMF,which agrees with the theoretical analysis.The ultra-low temperature dependence of the birefringence in the PM-PCF has great potential applications in temperature-insensitive fibre interferometers,fibre sensors,and fibre gyroscopes.
文摘The Social security system is a necessary part of market economic system, the social security fund is the basis of running a country social security system. However, the fund of social security of our country has many problems, such as investment channel phase contrast is still relatively narrow, the portfolio is not reasonable enough, external capital market is not perfect and so on.so the social security fund in our country is difficult to achieve effective and value. This article will start from the concept of sustainable development, and hope to find out the existing problems in the process of maintaining and increasing the value of social security funds through combing the basic elements of social security funds.
基金Project(50272019) supported by the National Natural Science Foundation of China project supported by China Postdoc toral Science Foundation
文摘An improved type of elliptical jacket polarization maintaining fiber was developed by using a modified chemical vapor deposition method with special treatment. Different from conventional elliptical jacket, the shape of the stress jacket was transmuted. The cross-section of fiber consists of 5 layers: substrate, outer cladding, stress jacket, inner cladding and core. The cross sectional component distribution was investigated by electron probe microscopy and energy dispersive spectrum. The finite element method was used to calculate the stress birefringence. Based on the analyses of the microstructure, the technological process is improved. The temperature cycling test of the fiber wound into gyroscope coils was performed. The results show that the fiber possesses superior performance at high and low temperatures compared with other fibers. The high homogeneity is achieved by well-controlled modified chemical vapor deposition process. A homogeneous length of 8 km fiber is obtained. With advantages in homogeneity and length, the fiber has great potential in applications such as fiber gyroscopes, fiber hydrophone and other optical fiber sensors.
文摘Recently,according to CNPC instructions,CNPC’s overseas projects,such as NGCP project in Saudi Arabia,CPL’s project in Bangladesh,XDEC’s project,and BHDC No.5 Drilling Company’s project,have maintained stable operations while fighting against the epidemic–COVID-19.
文摘Based on the results of plasma experiments and research work done by Dawson and Jones, Trubnikov, Endean, and other researchers, three requirements for producing and maintaining plasma ball lightning have been found: 1) rotation of plasma, 2) the density of charged particles nc > 3.15 × 10-10ω2,3) a stable confinement of plasma. In this model, the energy density of ball lightning ranged from 10-2 J / cm3 to 104 J/ cm3, the formation, shape, stability, energy, maintaining processes and other properties of ball lightning were explained reasonably.
文摘Foreign language learning is a complex process and its success is determined by a variety of factors.The prime one ofthem is motivation,which,as everyone knows,could be controlled by external forces so as to be taken advantage of.Motivationcould prompt the learner to have his own learning goals and let him finish his learning task autonomously.All of that shows the im-portance of maintaining learners’motivation.This paper will demonstrate not only the definition and the types of motivation,but al-so the methods that could be used to stimulate and maintain the motivation.
基金This work was supported by the Postgraduate Innovation Funding project of Hebei University(Grant No:hbu2020ss083).
文摘In today's society,obesity is the single most important risk factor for early disability and death,and the incidence of obesity is still at an alarming level.The central nervous system regulates energy intake and consumption in response to changes in the body's energy storage,thereby maintaining the body's continued obesity;fat cell-derived hormone leptin and its receptor(LEPR)are the key regulators of these systems.As in the case of insulin resistance,various mechanisms have been proposed(including feedback inhibition,inflammation,glial hyperplasia,and endoplasmic reticulum stress)to interfere with the action of leptin,hindering the system that controls the body's energy balance to promote or maintain obesity,although these are not clear.However,in ordinary obese patients,the LEPR signal may be increased(rather than impaired),indicating that any obesity-related defects in leptin action must be caused by lesions other than the original LEPR signal.
文摘BRICS proves it still has a major role to play in the development of emerging economies The BRICS partnership has proven that it is more relevant today than it ever has been,given that the polarization and protectionism of traditional global powers is at an all-time high.Experts believe that this trajectory has particularly
基金supported by National Institutes of Health(NIH),the National Institute of Arthritis and Musculoskeletal and Skin Diseases(NIAMS)Grant K01AR072123(ER-R)the American Society of Bone and Mineral Research(ASBMR)Rising Star awardprovided by NIH-National Institute of Diabetes and Digestive and Kidney Disease(NIDDK)Grant DK116056(MPC)。
文摘Bone formation is a highly energy-demanding process that can be impacted by metabolic disorders.Glucose has been considered the principal substrate for osteoblasts,although fatty acids are also important for osteoblast function.Here,we report that osteoblasts can derive energy from endogenous fatty acids stored in lipid droplets via lipolysis and that this process is critical for bone formation.As such,we demonstrate that osteoblasts accumulate lipid droplets that are highly dynamic and provide the molecular mechanism by which they serve as a fuel source for energy generation during osteoblast maturation.Inhibiting cytoplasmic lipolysis leads to both an increase in lipid droplet size in osteoblasts and an impairment in osteoblast function.The fatty acids released by lipolysis from these lipid droplets become critical for cellular energy production as cellular energetics shifts towards oxidative phosphorylation during nutrient-depleted conditions.In vivo,conditional deletion of the ATGL-encoding gene Pnpla2 in osteoblast progenitor cells reduces cortical and trabecular bone parameters and alters skeletal lipid metabolism.Collectively,our data demonstrate that osteoblasts store fatty acids in the form of lipid droplets,which are released via lipolysis to support cellular bioenergetic status when nutrients are limited.Perturbations in this process result in impairment of bone formation,specifically reducing ATP production and overall osteoblast function.
基金This work was supported by the Innovation Team Project no.sccxtd-2023-09 of the Modern Agricultural Industrious Technology System of Sichuan Provincethe Biological Breeding Project no.SKL-ZY202203 of the State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China.We thank A&L Scientific Editing(www.alpublish.com)for the linguistic assistance during the preparation of this manuscript.
文摘After harvest,potato tubers undergo an important period of dormancy,which significantly impacts potato quality and seed vigor.StSN2 has been reported as a key gene for maintaining tuber dormancy;in this study,we explored the molecular mechanism by which StSN2 maintains dormancy.StBIN2 was first identified as a candidate protein that interacts with StSN2 by co-immunoprecipitation/mass spectrometry,and both qPCR and enzyme activity experiments showed that StSN2 can promote the StBIN2 expression and activity.In addition,the interaction between StSN2 and StBIN2 was verified by yeast two-hybrid,luciferase complementation experiments and co-immunoprecipitation.Bioinformatics analysis and site-directed mutagenesis confirmed the critical role of cysteine residues of StBIN2 in its binding to StSN2.Similar to that of StSN2,overexpression of StBIN2 extended the dormancy of potato tuber.Interaction between StSN2 and StBIN2 increased the activity of the StBIN2 enzyme,inhibited the expression of StBZR1,and suppressed BR signaling.On the contrary,this interaction promoted the expression of StSnRK2.2/2.3/2.4/2.6 and StABI5,key genes of ABA signaling,and the phosphorylation of StSnRK2.3,thereby promoting ABA signaling.Altogether,our results indicate that StSN2 interacts with StBIN2 through key cysteine residues and StBIN2 maintains tuber dormancy by affecting ABA and BR signaling.Findings of this research offer new insights into the molecular mechanism by which StSN2 maintains potato tuber dormancy through interaction with StSIN2 and provide guidance for potato improvement.