A new fluorescent method was developed based on the ulifloxacin-europium(Ⅲ)-sodium dodecylbenzene sulfonate system for the determination of ulifloxacin,the active metabolite of prulifloxacin.Sodium dodecylbenzene s...A new fluorescent method was developed based on the ulifloxacin-europium(Ⅲ)-sodium dodecylbenzene sulfonate system for the determination of ulifloxacin,the active metabolite of prulifloxacin.Sodium dodecylbenzene sulfonate formed a ternary complex with ulifloxacin-europium(Ⅲ)and significantly enhanced the characteristic fluorescence of europium(Ⅲ).The enhanced fluorescence intensity showed a good linear relationship with the concentration of ulifloxacin in the range of 5.0×10^-8-2.0×10^-6M with a detection limit of 2.0×10^-10 M(3σ).This method is rapid and sensitive,and has been successfully applied to the determination of ulifloxacin in human urine and serum samples.展开更多
Dimension-reduced and decentralized learning i always viewed as an efficient way to solve multi-agent cooperative learning in high dimension. However, the dynamic environmen brought by the concurrent learning makes th...Dimension-reduced and decentralized learning i always viewed as an efficient way to solve multi-agent cooperative learning in high dimension. However, the dynamic environmen brought by the concurrent learning makes the decentralized learning hard to converge and bad in performance. To tackle thi problem, a timesharing-tracking framework(TTF), stemming from the idea that alternative learning in microscopic view results in concurrent learning in macroscopic view, is proposed in this paper, in which the joint-state best-response Q-learning(BRQ-learning) serves as the primary algorithm to adapt to the companions policies. With the properly defined switching principle, TTF makes all agents learn the best responses to others at different joint states. Thus from the view of the whole joint-state space, agents learn the optimal cooperative policy simultaneously. The simulation results illustrate that the proposed algorithm can learn the optimal joint behavior with les computation and faster speed compared with other two classica learning algorithms.展开更多
The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and etc.Motivated by this issue,a seven-level bo...The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and etc.Motivated by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this paper.The proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy generation.The configuration of topology and operating principles are illustrated in detail.The natural balance of capacitors and capacitance calculations are deduced as well.Moreover,the comparative study is conducted for different types of MLIs.The results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power loss.Finally,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.展开更多
As a wide-bandgap semiconductor(WBG), β-Ga_2O_3 is expected to be applied to power electronics and solar blind UV photodetectors. In this review, defects in β-Ga_2O_3 single crystals were summarized, including dislo...As a wide-bandgap semiconductor(WBG), β-Ga_2O_3 is expected to be applied to power electronics and solar blind UV photodetectors. In this review, defects in β-Ga_2O_3 single crystals were summarized, including dislocations, voids, twin, and small defects. Their effects on device performance were discussed. Dislocations and their surrounding regions can act as paths for the leakage current of SBD in single crystals. However, not all voids lead to leakage current. There's no strong evidence yet to show small defects affect the electrical properties. Doping impurity was definitely irrelated to the leakage current. Finally, the formation mechanism of the defects was analyzed. Most small defects were induced by mechanical damages. The screw dislocation originated from a subgrain boundary. The edge dislocation lying on a plane slightly tilted towards the(102) plane, the(101) being the possible slip plane. The voids defects like hollow nanopipes, PNPs, NSGs and line-shaped grooves may be caused by the condensation of excess oxygen vacancies, penetration of tiny bubbles or local meltback. The nucleation of twin lamellae occurred at the initial stage of "shoulder part" during the crystal growth. These results are helpful in controlling the occurrence of crystal defects and improving the device performance.展开更多
We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single ...We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.展开更多
Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has be...Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has been treated,and 4.405 million m^3 of water reaching the national urban miscellaneous water standard has been reclaimed and reused.A total of 25 km pipeline,5 pits,scenery fountains,lakes,and 12 pump stations have been constructed for flushing toilets,irrigating green grass lawn and afforest,and cleaning hardened pavement.The design and construction of 5 pits,scenery fountains,and lakes are important to meet the national urban miscellaneous water standard under occasional phosphorus and/or nitrogen exceed concentration.The unit water cost is 4.19 yuan/m^3,including membrane modules depreciation and amortization.After the A 2/O-MBR system passes the membrane modules depreciation and amortization period,the unit water cost is 2.82 yuan/m^3.The water productivity of the membrane stack rises first at the beginning of operation,reaches the maximum value,and then decreases.The average annual transmembrane pressure difference increases by 1.12 kPa.The average VMD of industrial permeability decreases annually by 0.45 m^3.展开更多
Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly...Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly considered in the countries’decision-making process.In this study,we evaluate the global temperature slowdown of the NDC scenario(ΔT=0.6°C)and attribute the global temperature slowdown to certain regions of the world with a compact earth system model.Considering reductions in CO_(2),CH_(4),N_(2)O,BC,and SO_(2),the R5OECD(the Organization for Economic Co-operation and Development in 1990)and R5ASIA(Asian countries)are the top two contributors to global warming mitigation,accounting for 39.3%and 36.8%,respectively.R5LAM(Latin America and the Caribbean)and R5MAF(the Middle East and Africa)followed behind,with contributions of 11.5%and 8.9%,respectively.The remaining 3.5%is attributed to R5REF(the Reforming Economies).Carbon Dioxide emission reduction is the decisive factor of regional contributions,but not the only one.Other greenhouse gases are also important,especially for R5MAF.The contribution of short-lived aerosols is small but significant,notably SO_(2)reduction in R5ASIA.We argue that additional species beyond CO_(2)need to be considered,including short-lived pollutants,when planning a route to mitigate climate change.It needs to be emphasized that there is still a gap to achieve the Paris Agreement 2-degree target with current NDC efforts,let alone the ambitious 1.5-degree target.All countries need to pursue stricter reduction policies for a more sustainable world.展开更多
From the roots of Ligularia macrophylla, a bisesquiterpene, ligumacrophyllal was isolated and its structure was elucidated on the basis of spectroscopic methods.
A new bisabolane sesquiterpene, 5 beta-acetoxy-4 beta, 8-diangeloyloxy-2 beta,3 beta, :10,11-diepoxy-bisabola-7 (14)-ene, was isolated from the roots of Ligularia songarica and its structure was elucidated on the basi...A new bisabolane sesquiterpene, 5 beta-acetoxy-4 beta, 8-diangeloyloxy-2 beta,3 beta, :10,11-diepoxy-bisabola-7 (14)-ene, was isolated from the roots of Ligularia songarica and its structure was elucidated on the basis of spectroscopic methods, especially 2D-NMR techniques.展开更多
We study the behaviors of three-dimensional double and triple Weyl fermions in the presence of weak random potential.By performing the Wilsonian renormalization group(RG)analysis,we reveal that the quasiparticle expe...We study the behaviors of three-dimensional double and triple Weyl fermions in the presence of weak random potential.By performing the Wilsonian renormalization group(RG)analysis,we reveal that the quasiparticle experiences strong renormalization which leads to the modification of the density of states and quasiparticle residue.We further utilize the RG analysis to calculate the classical conductivity and show that the diffusive transport is substantially corrected due to the novel behavior of the quasiparticle and can be directly measured by experiments.展开更多
BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can ...BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can effectively increase hemoglobin in patients with dialysis-dependent chronic kidney disease,with an adverse events profile comparable to that of epoetin alfa.We administered roxadustat to a maintenance hemodialysis patient who was allergic to erythropoiesis-stimulating agents(ESAs)and depended on blood transfusion for five years.After applying Roxadustat,the patient’s anemia improved significantly.CASE SUMMARY A 77-year-old Chinese man had type 2 diabetes for 16 years,underwent maintenance hemodialysis for five years,and had fatigue for five years.Laboratory tests showed severe anemia(hemoglobin concentration of 42 g/L).The patient was administered a subcutaneous injection of ESAs before dialysis.He suffered an allergic shock immediately and fainted.His blood pressure dropped to undetectable levels.He was not administered ESAs henceforth.The patient was prescribed iron supplements and received blood transfusions occasionally for five years.His hemoglobin concentration ranged from 42-68 g/L.After taking six weeks of oral roxadustat three times weekly(100 mg TIW),the patient’s hemoglobin concentration increased significantly,and his symptoms decreased.We adjusted the doses of roxadustat,and the hemoglobin concentration was maintained between 97 and 126 g/L.CONCLUSION Oral roxadustat is effective in treating anemia in maintenance hemodialysis patients who cannot be administered ESAs.展开更多
Dear Editor,This letter is concerned with quadratic L_(2) performance(quadratic stability and L_(2) gain)for switched uncertain linear systems(SULS)with norm-bounded uncertainties.Assuming that no single uncertain sub...Dear Editor,This letter is concerned with quadratic L_(2) performance(quadratic stability and L_(2) gain)for switched uncertain linear systems(SULS)with norm-bounded uncertainties.Assuming that no single uncertain subsystem achieves quadratic L_(2) performanceγbut a convex combination of the subsystems can make it,we propose a state-dependent switching law such that the SULS achieves the desired quadratic L_(2) performance.The discussion is extended to the SULS with state feedback control,and a sufficient condition is proposed to design the state feedback gains and the switching law simultaneously.展开更多
We report an exact numerical study on disorder effect in double-Weyl semimetals,and compare exact numerical solutions for the quasiparticle behavior with the Born approximation and renormalization group results.It is ...We report an exact numerical study on disorder effect in double-Weyl semimetals,and compare exact numerical solutions for the quasiparticle behavior with the Born approximation and renormalization group results.It is revealed that the low-energy quasiparticle properties are renormalized by multiple-impurity scattering processes,leading to apparent power-law behavior of the self-energy.Therefore,the quasiparticle residue surrounding nodal points is considerably reduced and vanishes as ZE∝Er with nonuniversal exponent.We show that such unusual behavior of the quasiparticle leads to strong temperature dependence of diffusive conductivity.Remarkably,we also find a universal minimum conductivity along the direction of linear dispersion at the nodal point,which can be directly observed by experimentalist.展开更多
AIM:To identify the effects of interleukin(IL)-13 on retinal pigment epithelial(RPE) cells and the IL-13 level in aqueous humor of age-related macular degeneration(AMD) patients.METHODS:IL-13 levels in aqueous...AIM:To identify the effects of interleukin(IL)-13 on retinal pigment epithelial(RPE) cells and the IL-13 level in aqueous humor of age-related macular degeneration(AMD) patients.METHODS:IL-13 levels in aqueous humor specimens from AMD patients were detected with enzyme-linked immunosorbent assay(ELISA).ARPE-19 cells were treated with 10 ng/m L IL-13 for 12,24,and 48 h.The cell proliferaton was evaluated by the MTS method.The m RNA and protein levels of α-SMA and ZO-1 were evaluated with quantitative real-time polymerase chain reaction(q RT-PCR) and Western blot respectively.The expression of tumor necrosis factor-α(TNF-α),transforming growth factor-β(TGF-β) and vascular endothelial growth factor(VEGF) were assessed by ELISA.RESU LTS:IL-13 levels in the aqueous humor of patients with AMD were significantly higher than those in the control(167.33±17.64 vs 27.12±5.65 pg/m L;P〈0.01).In vit ro,IL-13 of high concentrations(10,15,and 20 ng/m L) inhibited ARPE-19 cell proliferation.α-SMA m RNA in ARPE-19 cell were increased(1.017±0.112 vs 1.476±0.168;P〈0.001) and ZO-1 decreased(1.051±0.136 vs 0.702±0.069;P〈0.001) after treated with 10 ng/m L IL-13 for 48 h.The protein expression of α-SMA and ZO-1 also showed the same tendency(α-SMA:P=0.038;ZO-1:P=0.008).IL-13 significantly reduced the level of TNF-α(44.70±1.67 vs 31.79±3.53 pg/m L;P=0.005) at 48 h,but the le vel of TGF-β2 was significantly increased from 34.44±2.92 to 57.61±6.31 pg/m L at 24h(P=0.004) and from 61.26±1.11 to 86.91±3.59 pg/m L at 48h(P〈0.001).While expressions of VEGF didn't change after IL-13 treatment.CONCLUSION:IL-13 in vitr o inhibit ARPE-19 cell proliferation and expression in the aqueous may be associated with AMD.展开更多
With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to humans.However,we know little about the fundamental working mechanism of pre-trained models in w...With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to humans.However,we know little about the fundamental working mechanism of pre-trained models in which we do not know how they approach such performance and how the task is solved by the model.For example,given a task,human learns from easy to hard,whereas the model learns randomly.Undeniably,difficulty-insensitive learning leads to great success in natural language processing(NLP),but little attention has been paid to the effect of text difficulty in NLP.We propose a human learning matching index(HLM Index)to investigate the effect of text difficulty.Experiment results show:1)LSTM gives more human-like learning behavior than BERT.Additionally,UID-SuperLinear gives the best evaluation of text difficulty among four text difficulty criteria.Among nine tasks,some tasks’performance is related to text difficulty,whereas others are not.2)Model trained on easy data performs best in both easy and medium test data,whereas trained on hard data only performs well on hard test data.3)Train the model from easy to hard,leading to quicker convergence.展开更多
The rapid spread of mobile tigecycline resistance presents a significant public health threat,particularly with the increasing prevalence of tet(X4)-positive Enterobacterales across various species.This study aimed to...The rapid spread of mobile tigecycline resistance presents a significant public health threat,particularly with the increasing prevalence of tet(X4)-positive Enterobacterales across various species.This study aimed to inves-tigate the epidemic features and transmission dynamics of tet(X4)-positive Klebsiella pneumoniae(K.pneumo-niae)through the analysis of 206 raw meats,including pork(n=182),beef(n=16),duck(n=5),and chicken(n=3).These samples were collected from schools,markets,and restaurants in Chengdu City,China.A total of 25 isolates were obtained from 13 administrative regions.All isolates exhibited resistance to tetracycline,tigecycline,ampicillin,chloramphenicol,and florfenicol.Over half of the isolates also demon-strated resistance to streptomycin(80%),sulfamethoxazole/trimethoprim(72%),ciprofloxacin(64%),and ampicillin/sulbactam(56%).Among these strains,14 distinct sequence types(STs)were identified,revealing evidence of inter-regional clonal spread,notably among 9 K.pneumoniae ST3393.Phylogenetic analysis revealed the presence of two K.pneumoniae ST5 closely resembling hypervirulent K.pneumoniae from Jiangsu.Importantly,12 isolates were capable of transferring tigecycline resistance to Escherichia coli J53.Further plasmid analysis showed that the tet(X4)-harboring plasmids in K.pneumoniae could be classified into four types,primarily belonging to the IncFIA(HI1)/HI1A/HI1B hybrid plasmid(n=16)and IncFII plasmid(n=7),which significantly contributed to the cross-species dissemination of tet(X4).In summary,this study highlights the prevalence of MDR tet(X4)-positive K.pneumoniae in Chengdu,driven predominantly by clonal expansion and plasmid-mediated horizontal gene transfer.These findings emphasize the importance of contin-uous surveillance of tet(X4)-positive K.pneumoniae in raw meat and the implementation of effective measures to control their spread.展开更多
We report bound states of solitons from a harmonic mode-locked fiber laser based on a solution-processed graphene saturable absorber. Stable soliton pairs, 26.2 ps apart, are generated with 720 fs duration. By simply ...We report bound states of solitons from a harmonic mode-locked fiber laser based on a solution-processed graphene saturable absorber. Stable soliton pairs, 26.2 ps apart, are generated with 720 fs duration. By simply increasing the pump power, the laser can also generate harmonic mode-locking with harmonics up to the26 th order(409.6 MHz repetition rate). This is a simple, low-cost, all-fiber, versatile multifunction ultrafast laser that could be used for many applications.展开更多
基金supported by the National Natural Science Foundation of China(Nos.20875056,20775043)
文摘A new fluorescent method was developed based on the ulifloxacin-europium(Ⅲ)-sodium dodecylbenzene sulfonate system for the determination of ulifloxacin,the active metabolite of prulifloxacin.Sodium dodecylbenzene sulfonate formed a ternary complex with ulifloxacin-europium(Ⅲ)and significantly enhanced the characteristic fluorescence of europium(Ⅲ).The enhanced fluorescence intensity showed a good linear relationship with the concentration of ulifloxacin in the range of 5.0×10^-8-2.0×10^-6M with a detection limit of 2.0×10^-10 M(3σ).This method is rapid and sensitive,and has been successfully applied to the determination of ulifloxacin in human urine and serum samples.
文摘Dimension-reduced and decentralized learning i always viewed as an efficient way to solve multi-agent cooperative learning in high dimension. However, the dynamic environmen brought by the concurrent learning makes the decentralized learning hard to converge and bad in performance. To tackle thi problem, a timesharing-tracking framework(TTF), stemming from the idea that alternative learning in microscopic view results in concurrent learning in macroscopic view, is proposed in this paper, in which the joint-state best-response Q-learning(BRQ-learning) serves as the primary algorithm to adapt to the companions policies. With the properly defined switching principle, TTF makes all agents learn the best responses to others at different joint states. Thus from the view of the whole joint-state space, agents learn the optimal cooperative policy simultaneously. The simulation results illustrate that the proposed algorithm can learn the optimal joint behavior with les computation and faster speed compared with other two classica learning algorithms.
基金supported by the National Natural Science Foundation of China under Grants 62173148 and 52377186,and Joint Laboratory of Energy Saving and Intelligent Maintenance for Modern Transportations。
文摘The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and etc.Motivated by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this paper.The proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy generation.The configuration of topology and operating principles are illustrated in detail.The natural balance of capacitors and capacitance calculations are deduced as well.Moreover,the comparative study is conducted for different types of MLIs.The results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power loss.Finally,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.
基金the Financial support from the National key Research and Development Program of China(Nso.2018YFB0406502,2016YFB1102201)the National Natural Science Foundation of China(Grant No.51321091)+2 种基金the key Research and Development Program of Shandong Province(No.2018CXGC0410)the Young Scholars Program of Shandong University(No.2015WLJH36)the 111 Project 2.0(No.BP2018013)
文摘As a wide-bandgap semiconductor(WBG), β-Ga_2O_3 is expected to be applied to power electronics and solar blind UV photodetectors. In this review, defects in β-Ga_2O_3 single crystals were summarized, including dislocations, voids, twin, and small defects. Their effects on device performance were discussed. Dislocations and their surrounding regions can act as paths for the leakage current of SBD in single crystals. However, not all voids lead to leakage current. There's no strong evidence yet to show small defects affect the electrical properties. Doping impurity was definitely irrelated to the leakage current. Finally, the formation mechanism of the defects was analyzed. Most small defects were induced by mechanical damages. The screw dislocation originated from a subgrain boundary. The edge dislocation lying on a plane slightly tilted towards the(102) plane, the(101) being the possible slip plane. The voids defects like hollow nanopipes, PNPs, NSGs and line-shaped grooves may be caused by the condensation of excess oxygen vacancies, penetration of tiny bubbles or local meltback. The nucleation of twin lamellae occurred at the initial stage of "shoulder part" during the crystal growth. These results are helpful in controlling the occurrence of crystal defects and improving the device performance.
基金supported in part by the Japan Ministry of Education,Sciences and Culture under Grants-in-Aid for Scientific Research(C)(21560471)the Green Industry Leading Program of Hubei University of Technology(CPYF2017003)the National Natural Science Foundation of China(1160147411461082)
文摘We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.
文摘Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has been treated,and 4.405 million m^3 of water reaching the national urban miscellaneous water standard has been reclaimed and reused.A total of 25 km pipeline,5 pits,scenery fountains,lakes,and 12 pump stations have been constructed for flushing toilets,irrigating green grass lawn and afforest,and cleaning hardened pavement.The design and construction of 5 pits,scenery fountains,and lakes are important to meet the national urban miscellaneous water standard under occasional phosphorus and/or nitrogen exceed concentration.The unit water cost is 4.19 yuan/m^3,including membrane modules depreciation and amortization.After the A 2/O-MBR system passes the membrane modules depreciation and amortization period,the unit water cost is 2.82 yuan/m^3.The water productivity of the membrane stack rises first at the beginning of operation,reaches the maximum value,and then decreases.The average annual transmembrane pressure difference increases by 1.12 kPa.The average VMD of industrial permeability decreases annually by 0.45 m^3.
基金funded by the undergraduate student research training program of the Ministry of Education, the National Natural Science Foundation of China (Grants Nos. 41771495, 41830641, and 41988101)the Second Tibetan Plateau Scientific Expedition and Research Program Grant 2019QZKK0208+1 种基金funded by the European Research Council Synergy project “Imbalance-P ” (Grant No. ERC-2013-Sy G-610028)the European Union’s Horizon 2020 research and innovation project “CONSTRAIN” (Grant No. 820829)
文摘Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly considered in the countries’decision-making process.In this study,we evaluate the global temperature slowdown of the NDC scenario(ΔT=0.6°C)and attribute the global temperature slowdown to certain regions of the world with a compact earth system model.Considering reductions in CO_(2),CH_(4),N_(2)O,BC,and SO_(2),the R5OECD(the Organization for Economic Co-operation and Development in 1990)and R5ASIA(Asian countries)are the top two contributors to global warming mitigation,accounting for 39.3%and 36.8%,respectively.R5LAM(Latin America and the Caribbean)and R5MAF(the Middle East and Africa)followed behind,with contributions of 11.5%and 8.9%,respectively.The remaining 3.5%is attributed to R5REF(the Reforming Economies).Carbon Dioxide emission reduction is the decisive factor of regional contributions,but not the only one.Other greenhouse gases are also important,especially for R5MAF.The contribution of short-lived aerosols is small but significant,notably SO_(2)reduction in R5ASIA.We argue that additional species beyond CO_(2)need to be considered,including short-lived pollutants,when planning a route to mitigate climate change.It needs to be emphasized that there is still a gap to achieve the Paris Agreement 2-degree target with current NDC efforts,let alone the ambitious 1.5-degree target.All countries need to pursue stricter reduction policies for a more sustainable world.
基金This work was supported by the NNSFC (No. 29972017).
文摘From the roots of Ligularia macrophylla, a bisesquiterpene, ligumacrophyllal was isolated and its structure was elucidated on the basis of spectroscopic methods.
文摘A new bisabolane sesquiterpene, 5 beta-acetoxy-4 beta, 8-diangeloyloxy-2 beta,3 beta, :10,11-diepoxy-bisabola-7 (14)-ene, was isolated from the roots of Ligularia songarica and its structure was elucidated on the basis of spectroscopic methods, especially 2D-NMR techniques.
基金Project supported by the National Natural Science Foundation of China(Grant No.11874337).
文摘We study the behaviors of three-dimensional double and triple Weyl fermions in the presence of weak random potential.By performing the Wilsonian renormalization group(RG)analysis,we reveal that the quasiparticle experiences strong renormalization which leads to the modification of the density of states and quasiparticle residue.We further utilize the RG analysis to calculate the classical conductivity and show that the diffusive transport is substantially corrected due to the novel behavior of the quasiparticle and can be directly measured by experiments.
文摘BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can effectively increase hemoglobin in patients with dialysis-dependent chronic kidney disease,with an adverse events profile comparable to that of epoetin alfa.We administered roxadustat to a maintenance hemodialysis patient who was allergic to erythropoiesis-stimulating agents(ESAs)and depended on blood transfusion for five years.After applying Roxadustat,the patient’s anemia improved significantly.CASE SUMMARY A 77-year-old Chinese man had type 2 diabetes for 16 years,underwent maintenance hemodialysis for five years,and had fatigue for five years.Laboratory tests showed severe anemia(hemoglobin concentration of 42 g/L).The patient was administered a subcutaneous injection of ESAs before dialysis.He suffered an allergic shock immediately and fainted.His blood pressure dropped to undetectable levels.He was not administered ESAs henceforth.The patient was prescribed iron supplements and received blood transfusions occasionally for five years.His hemoglobin concentration ranged from 42-68 g/L.After taking six weeks of oral roxadustat three times weekly(100 mg TIW),the patient’s hemoglobin concentration increased significantly,and his symptoms decreased.We adjusted the doses of roxadustat,and the hemoglobin concentration was maintained between 97 and 126 g/L.CONCLUSION Oral roxadustat is effective in treating anemia in maintenance hemodialysis patients who cannot be administered ESAs.
基金the National Natural Science Foundation of China(61903129)。
文摘Dear Editor,This letter is concerned with quadratic L_(2) performance(quadratic stability and L_(2) gain)for switched uncertain linear systems(SULS)with norm-bounded uncertainties.Assuming that no single uncertain subsystem achieves quadratic L_(2) performanceγbut a convex combination of the subsystems can make it,we propose a state-dependent switching law such that the SULS achieves the desired quadratic L_(2) performance.The discussion is extended to the SULS with state feedback control,and a sufficient condition is proposed to design the state feedback gains and the switching law simultaneously.
基金Supported by the the National Natural Science Foundation of China(Grant No.11874337)。
文摘We report an exact numerical study on disorder effect in double-Weyl semimetals,and compare exact numerical solutions for the quasiparticle behavior with the Born approximation and renormalization group results.It is revealed that the low-energy quasiparticle properties are renormalized by multiple-impurity scattering processes,leading to apparent power-law behavior of the self-energy.Therefore,the quasiparticle residue surrounding nodal points is considerably reduced and vanishes as ZE∝Er with nonuniversal exponent.We show that such unusual behavior of the quasiparticle leads to strong temperature dependence of diffusive conductivity.Remarkably,we also find a universal minimum conductivity along the direction of linear dispersion at the nodal point,which can be directly observed by experimentalist.
文摘AIM:To identify the effects of interleukin(IL)-13 on retinal pigment epithelial(RPE) cells and the IL-13 level in aqueous humor of age-related macular degeneration(AMD) patients.METHODS:IL-13 levels in aqueous humor specimens from AMD patients were detected with enzyme-linked immunosorbent assay(ELISA).ARPE-19 cells were treated with 10 ng/m L IL-13 for 12,24,and 48 h.The cell proliferaton was evaluated by the MTS method.The m RNA and protein levels of α-SMA and ZO-1 were evaluated with quantitative real-time polymerase chain reaction(q RT-PCR) and Western blot respectively.The expression of tumor necrosis factor-α(TNF-α),transforming growth factor-β(TGF-β) and vascular endothelial growth factor(VEGF) were assessed by ELISA.RESU LTS:IL-13 levels in the aqueous humor of patients with AMD were significantly higher than those in the control(167.33±17.64 vs 27.12±5.65 pg/m L;P〈0.01).In vit ro,IL-13 of high concentrations(10,15,and 20 ng/m L) inhibited ARPE-19 cell proliferation.α-SMA m RNA in ARPE-19 cell were increased(1.017±0.112 vs 1.476±0.168;P〈0.001) and ZO-1 decreased(1.051±0.136 vs 0.702±0.069;P〈0.001) after treated with 10 ng/m L IL-13 for 48 h.The protein expression of α-SMA and ZO-1 also showed the same tendency(α-SMA:P=0.038;ZO-1:P=0.008).IL-13 significantly reduced the level of TNF-α(44.70±1.67 vs 31.79±3.53 pg/m L;P=0.005) at 48 h,but the le vel of TGF-β2 was significantly increased from 34.44±2.92 to 57.61±6.31 pg/m L at 24h(P=0.004) and from 61.26±1.11 to 86.91±3.59 pg/m L at 48h(P〈0.001).While expressions of VEGF didn't change after IL-13 treatment.CONCLUSION:IL-13 in vitr o inhibit ARPE-19 cell proliferation and expression in the aqueous may be associated with AMD.
基金the support of the National Natural Science Foundation of China(Nos.U22B2059,62176079)National Natural Science Foundation of Heilongjiang Province,China(No.YQ 2022F005)the Industry-University-Research Innovation Foundation of China University(No.2021ITA05009).
文摘With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to humans.However,we know little about the fundamental working mechanism of pre-trained models in which we do not know how they approach such performance and how the task is solved by the model.For example,given a task,human learns from easy to hard,whereas the model learns randomly.Undeniably,difficulty-insensitive learning leads to great success in natural language processing(NLP),but little attention has been paid to the effect of text difficulty in NLP.We propose a human learning matching index(HLM Index)to investigate the effect of text difficulty.Experiment results show:1)LSTM gives more human-like learning behavior than BERT.Additionally,UID-SuperLinear gives the best evaluation of text difficulty among four text difficulty criteria.Among nine tasks,some tasks’performance is related to text difficulty,whereas others are not.2)Model trained on easy data performs best in both easy and medium test data,whereas trained on hard data only performs well on hard test data.3)Train the model from easy to hard,leading to quicker convergence.
基金supported by the National Key Research and Development Program of China(No.2022YFD1800400)National Natural Science Foundation of China(No.81991531)+1 种基金Natural Science Foundation of Shandong Province(No.ZR2020MC188)The sequence data of 25 K.pneumoniae isolates have been submitted to NCBI under BioProject accession number PRJNA1011004.
文摘The rapid spread of mobile tigecycline resistance presents a significant public health threat,particularly with the increasing prevalence of tet(X4)-positive Enterobacterales across various species.This study aimed to inves-tigate the epidemic features and transmission dynamics of tet(X4)-positive Klebsiella pneumoniae(K.pneumo-niae)through the analysis of 206 raw meats,including pork(n=182),beef(n=16),duck(n=5),and chicken(n=3).These samples were collected from schools,markets,and restaurants in Chengdu City,China.A total of 25 isolates were obtained from 13 administrative regions.All isolates exhibited resistance to tetracycline,tigecycline,ampicillin,chloramphenicol,and florfenicol.Over half of the isolates also demon-strated resistance to streptomycin(80%),sulfamethoxazole/trimethoprim(72%),ciprofloxacin(64%),and ampicillin/sulbactam(56%).Among these strains,14 distinct sequence types(STs)were identified,revealing evidence of inter-regional clonal spread,notably among 9 K.pneumoniae ST3393.Phylogenetic analysis revealed the presence of two K.pneumoniae ST5 closely resembling hypervirulent K.pneumoniae from Jiangsu.Importantly,12 isolates were capable of transferring tigecycline resistance to Escherichia coli J53.Further plasmid analysis showed that the tet(X4)-harboring plasmids in K.pneumoniae could be classified into four types,primarily belonging to the IncFIA(HI1)/HI1A/HI1B hybrid plasmid(n=16)and IncFII plasmid(n=7),which significantly contributed to the cross-species dissemination of tet(X4).In summary,this study highlights the prevalence of MDR tet(X4)-positive K.pneumoniae in Chengdu,driven predominantly by clonal expansion and plasmid-mediated horizontal gene transfer.These findings emphasize the importance of contin-uous surveillance of tet(X4)-positive K.pneumoniae in raw meat and the implementation of effective measures to control their spread.
基金National Natural Science Foundation of China(NSFC)(61575106)Beihang University(BUAA)+1 种基金Beijing Advanced Innovation Center for Big Data-Based Precision Medicine(Ultrafast Pulsed Fiber Lasers and Applications)School of Instrumentation and Optoelectronic Engineering
文摘We report bound states of solitons from a harmonic mode-locked fiber laser based on a solution-processed graphene saturable absorber. Stable soliton pairs, 26.2 ps apart, are generated with 720 fs duration. By simply increasing the pump power, the laser can also generate harmonic mode-locking with harmonics up to the26 th order(409.6 MHz repetition rate). This is a simple, low-cost, all-fiber, versatile multifunction ultrafast laser that could be used for many applications.