The development of technologies such as big data and blockchain has brought convenience to life,but at the same time,privacy and security issues are becoming more and more prominent.The K-anonymity algorithm is an eff...The development of technologies such as big data and blockchain has brought convenience to life,but at the same time,privacy and security issues are becoming more and more prominent.The K-anonymity algorithm is an effective and low computational complexity privacy-preserving algorithm that can safeguard users’privacy by anonymizing big data.However,the algorithm currently suffers from the problem of focusing only on improving user privacy while ignoring data availability.In addition,ignoring the impact of quasi-identified attributes on sensitive attributes causes the usability of the processed data on statistical analysis to be reduced.Based on this,we propose a new K-anonymity algorithm to solve the privacy security problem in the context of big data,while guaranteeing improved data usability.Specifically,we construct a new information loss function based on the information quantity theory.Considering that different quasi-identification attributes have different impacts on sensitive attributes,we set weights for each quasi-identification attribute when designing the information loss function.In addition,to reduce information loss,we improve K-anonymity in two ways.First,we make the loss of information smaller than in the original table while guaranteeing privacy based on common artificial intelligence algorithms,i.e.,greedy algorithm and 2-means clustering algorithm.In addition,we improve the 2-means clustering algorithm by designing a mean-center method to select the initial center of mass.Meanwhile,we design the K-anonymity algorithm of this scheme based on the constructed information loss function,the improved 2-means clustering algorithm,and the greedy algorithm,which reduces the information loss.Finally,we experimentally demonstrate the effectiveness of the algorithm in improving the effect of 2-means clustering and reducing information loss.展开更多
Trimethylamine N-oxide(TMAO)is a risk factor of various chronic diseases,which was produced by metabolism from precursors to trimethylamine(TMA)in gut and the oxidation from TMA in liver.The TMA generation was influen...Trimethylamine N-oxide(TMAO)is a risk factor of various chronic diseases,which was produced by metabolism from precursors to trimethylamine(TMA)in gut and the oxidation from TMA in liver.The TMA generation was influenced by diet,mainly due to the rich TMAO precursors in diet.However,it was still unclear that the effects of different proportion and source of macronutrients in different dietary pattern on the production process of TMAO.Here,the generation of TMA from precursors and TMAO from TMA was determined after single oral choline chloride and intraperitoneal injection TMA,respectively,in mice fed with carbohydrates,proteins and fats in different proportion and sources.The results suggested that the generation of TMAO was increased by low non-meat protein and high fat via enhancing the production of TMAO from TMA,and decreased by plant protein and refined sugar via reducing TMA production from precursors in gut and TMAO transformation from TMA in liver.The high fat and high sugar diets accelerating the development of atherosclerosis did not increase the production of TMAO,the risk factor for atherosclerosis,which indicated that the dietary compositions rather than the elevated TMAO level might be a more key risk factor for atherosclerosis.展开更多
Sea cucumber saponins have attracted more attention in recent years due to biological activities.It is a popular practice to soak sea cucumber in Baijiu at home and being applied to industrial manufacturing in China.H...Sea cucumber saponins have attracted more attention in recent years due to biological activities.It is a popular practice to soak sea cucumber in Baijiu at home and being applied to industrial manufacturing in China.However,knowledge of the effect of alcohol on the absorption and metabolism of sea cucumber saponins is limited.The effects of alcohol on digestion,absorption and metabolism of sea cucumber saponins in BALB/c mice were investigated after gavage and tail intravenous injection.The results showed that the content of saponins in serum and liver was significantly higher under the influence of alcohol than that in the control group after oral administration.Alcohol promoted the absorption of sea cucumber saponins prototype as well as inhibited the process of saponins being transformed into deglycositic metabolites in the small intestine.Moreover,sea cucumber saponins remained in circulation for a long time and alcohol slowed down the clearance of sea cucumber saponins under the influence of alcohol after intravenous injection.This confirmed the feasibility of marinating sea cucumber in Baijiu to improve the efficacy of saponins and provides an important theoretical basis for the utilization of sea cucumber and the development of sea cucumber liquor.展开更多
Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonrecip...Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonreciprocal devices rely on a strong magnetic field,which is provided by a permanent magnet.As a result,the isolation direction of such devices is fixed and severely restricts their applications in quantum networks.In this work,we experimentally demonstrate the simultaneous one-way transmission and unidirectional reflection by using a magneto-optical Fabry-Pérot cavity and a magnetic field strength of 50 mT.An optical isolator and a three-port quasi-circulator are realized based on this nonreciprocal cavity system.The isolator achieves an isolation ratio of up to 22 dB and an averaged insertion loss down to 0.97 dB.The quasi-circulator is realized with a fidelity exceeding 99% and an overall survival probability of 89.9%,corresponding to an insertion loss of~0.46 dB.The magnetic field is provided by an electromagnetic coil,thereby allowing for reversing the light circulating path.The reversible quasi-circulator paves the way for building reconfigurable quantum networks.展开更多
A massive rock and ice avalanche occurred on the western slope of the Ronti Gad valley in the northern part of Chamoli,Indian Himalaya,on 7 February 7,2021.The avalanche on the high mountain slope at an elevation of 5...A massive rock and ice avalanche occurred on the western slope of the Ronti Gad valley in the northern part of Chamoli,Indian Himalaya,on 7 February 7,2021.The avalanche on the high mountain slope at an elevation of 5600 m above sea level triggered a long runout disaster chain,including rock mass avalanche,debris avalanche,and flood.The disaster chain had a horizontal travel distance of larger than 17,600 m and an elevation difference of 4300 m.In this study,the disaster characteristics and dynamic process were analyzed by multitemporal satellite imagery.The results show that the massive rock and ice avalanche was caused by four large expanding discontinuity planes.The disaster chain was divided into five zones by satellite images and field observation,including source zone,transition zone,dynamic entrainment zone,flow deposition zone,and flood zone.The entrainment effect and melting water were recognized as the main causes of the long-runout distance.Based on the seismic wave records and field videos,the time progress of the disaster was analyzed and the velocity of frontal debris at different stages was calculated.The total analyzed disaster duration was 1247 s,and the frontal debris velocity colliding with the second hydropower station was approximately 23 m/s.This study also carried out the numerical simulation of the disaster by rapid mass movement simulation(RAMMS).The numerical results reproduced the dynamic process of the debris avalanche,and the mechanism of long-runout avalanche was further verified by parametric study.Furthermore,this study discussed the potential causes of disaster and flood and the roles of satellite images and seismic networks in the monitoring and early-warning.展开更多
Radio frequency fingerprinting(RFF)is a remarkable lightweight authentication scheme to support rapid and scalable identification in the internet of things(IoT)systems.Deep learning(DL)is a critical enabler of RFF ide...Radio frequency fingerprinting(RFF)is a remarkable lightweight authentication scheme to support rapid and scalable identification in the internet of things(IoT)systems.Deep learning(DL)is a critical enabler of RFF identification by leveraging the hardware-level features.However,traditional supervised learning methods require huge labeled training samples.Therefore,how to establish a highperformance supervised learning model with few labels under practical application is still challenging.To address this issue,we in this paper propose a novel RFF semi-supervised learning(RFFSSL)model which can obtain a better performance with few meta labels.Specifically,the proposed RFFSSL model is constituted by a teacher-student network,in which the student network learns from the pseudo label predicted by the teacher.Then,the output of the student model will be exploited to improve the performance of teacher among the labeled data.Furthermore,a comprehensive evaluation on the accuracy is conducted.We derive about 50 GB real long-term evolution(LTE)mobile phone’s raw signal datasets,which is used to evaluate various models.Experimental results demonstrate that the proposed RFFSSL scheme can achieve up to 97%experimental testing accuracy over a noisy environment only with 10%labeled samples when training samples equal to 2700.展开更多
This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzz...This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzzy model. To save the network communication burden, a distributed dynamic event-triggered mechanism is developed to restrain the information update. Besides, random packet dropouts following the Bernoulli distribution are assumed to occur in sensor to controller channels, where the triggered control input is analyzed via an equivalent method containing a new stochastic variable. By establishing the mode-dependent Lyapunov–Krasovskii functional with augmented terms, the finite-time boundness of the error system limited to strict dissipativity is studied. As a result of the help of an extended reciprocally convex matrix inequality technique, less conservative criteria in terms of linear matrix inequalities are deduced to calculate the desired control gains. Finally, two examples in regard to practical systems are provided to display the effectiveness of the proposed theory.展开更多
Electrochemical CO_(2)reduction to C_(2)H_(4)can provide a sustainable route to reduce globally accelerating CO_(2)emissions and produce energy-rich chemical feedstocks.However,the poor selectivity in C_(2)H_(4)electr...Electrochemical CO_(2)reduction to C_(2)H_(4)can provide a sustainable route to reduce globally accelerating CO_(2)emissions and produce energy-rich chemical feedstocks.However,the poor selectivity in C_(2)H_(4)electrosynthesis limits its implementation in industrially interesting processes.Herein,we report a composite structured catalyst composed of Ag and Cu_(2)O with different crystal faces to achieve highly efficient reduction of CO_(2)to C_(2)H_(4).The catalyst composed of Ag and octahedral Cu_(2)O enclosed with(111)facet exhibits the best CO_(2)electroreduction performance,with the Faradaic efficiency(FE)and partial current density reaching 66.8%and 17.8 mA cm2 for C_(2)H_(4)product at-1.2 VRHE in 0.5 M KHCO_(3),respectively.Physical characterization and electrochemical test analysis indicate that the high selectivity for C_(2)H_(4)product stems from the synergistic effect of crystal faces control engineering and tandem catalysis.Specifically,Ag can provide optimal availability of CO intermediate by suppressing hydrogen evolution;subsequently,C-C coupling is promoted on the intimate surface of Cu_(2)O with facetdependent selectivity.The insights gained from this work may be beneficial for designing efficient multicomponent catalysts for improving the selectivity of electrochemical CO_(2)reduction reaction to generate C2þproducts.展开更多
Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'...Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.展开更多
Antarctic krill(Euphausia superba)oil has been gaining increasing attention due to its nutritional and functional potentials.Krill oil usually contains a high concentration(about 50%)of phospholipids(AKOP)rich in DHA ...Antarctic krill(Euphausia superba)oil has been gaining increasing attention due to its nutritional and functional potentials.Krill oil usually contains a high concentration(about 50%)of phospholipids(AKOP)rich in DHA and EPA accompanied with 30%–40%triacylglycerols.Phospholipids can be made into liposomes without emulsifiers due to its amphiphilic characteristics.However,the absorption kinetics of AKOP liposome in vivo is not clear,which restrict the molecular mechanism analysis related to its distinct bioactivities.The lipid analysis in serum,small intestinal content and wall was carried out after oral administration of AKOP liposome to illustrate its absorption kinetics in blood and the digestive tract of healthy mice by single gavage.The major type of the obtained AKOP was phosphatidylcholine,and the total contents of the DHA and EPA were 29.31%.AKOP liposome was almost completely digested in the small intestine in 1 h and the hydrolysis products could be quickly absorbed by intestinal enterocytes.The DHA in serum peaked at 2 h after administration of AKOP liposome.AKOP liposome could be quickly digested and absorbed in vivo.The obtained results might provide a scientific basis for the molecular mechanism analysis related to distinct bioactivities of Antarctic krill oil phospholipid.展开更多
Topological materials have novel properties both in their bulk and boundaries,thereby attracting a wide interest in the theoretical and experimental communities.The recent development of the topological quantum chemis...Topological materials have novel properties both in their bulk and boundaries,thereby attracting a wide interest in the theoretical and experimental communities.The recent development of the topological quantum chemistry and symmetrybased indicator theory in this field has significantly simplified the procedure for determining the topological properties of nonmagnetic crystalline materials.Accordingly,a large number of new topological materials have been found by scanning large crystal databases.This study provides details on the algorithm used in the Catalogue of Topological Electronic Materials.Moreover,based on the algorithm,we develop an automatic package named SymTopo,which calculates the symmetry representations of any given nonmagnetic crystalline material and predicts its topological properties.This package may facilitate the discovery of more topological materials in the future.展开更多
Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme s...Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme seedlings in response to inorganic Cd stress,we cultured the seedlings under two different Cd levels:natural seawater and high Cd stress.High Cd stress significantly inhibited the seedlings growth,and darkened the thalli color.Additionally,the pigment contents,growth rate,peroxidase(POD)activity,dehydroascorbic acid(DHA)content,and glutathione reductase(GR)activity in S.fusiforme were significantly reduced by high Cd treatment.Contrarily,the Cd accumulation,Cd2+absorption rate,dark respiration/net photosynthetic rate(Rd/Pn),ascorbic acid(Vc)content,soluble protein(SP)content,glutathione(GSH),and the activities of superoxide dismutase(SOD)and catalase(CAT)of S.fusiforme under Cd treatment significantly increased compared to the control group.The decrease of malondialdehyde(MDA)was not significant.Although S.fusiforme seedlings increased the antioxidant activities of POD,SOD,Vc,and the AsA-GSH cycle to disseminate H2O2 and maintain healthy metabolism,high Cd stress caused Cd accumulation in the stem and leaves of S.fusiforme seedlings.The excessive Cd significantly restricted photosynthesis and reduced photosynthetic pigments in the seedlings,resulting in growth inhibition and deep morphological color,especially of the stems.High levels of Cd in seawater had toxic effects on commercial S.fusiforme seedlings,and risked this edible seaweed for human food.展开更多
The use of multiple-choice(MC)question types has been one of the most contentious issues in language testing.Much has been said and written about the use of MC over the years.However,no attempt has ever been made to i...The use of multiple-choice(MC)question types has been one of the most contentious issues in language testing.Much has been said and written about the use of MC over the years.However,no attempt has ever been made to introduce any innovation in test item types.The researchers proposed a jumbled words test item(JW)based on cognitive science and deep learning principles,and addressed the feasibility of replacing the type of multiple-choice(MC)question with JW to meet the ongoing rapid development of language testing practice.Two research questions were proposed ad hoc,focusing on the co-relationship between JW and MC scores.RASCH-GZ was used to perform item analyses(Rasch,1960).The item difficulty parameters thus obtained were used to compare the two different test items.The sample data metric includes 40 Chinese participants.The findings revealed that correlation analysis revealed that the performance of the same group of subjects taking both JW and MC was not relevant(Pearson Corr=0).This is primarily due to the total elimination of guessing factors inherent in test-takers during JW test performance.Three factors were specified for the design of the JW test:compute program,test difficulty,and score acceptability.These all have three dimensions.Data collected through questionnaires were analyzed using EFA in SPSS V.24.0.KMOs(=0.867)were found to be approximately one and significance at 0.000(0.05),indicating that the construct of theuestionnaire thus designed has better validity for factor analysis.Three important conclusions were obtained,the implications of which could provide impetus for our testing counterparts to practice more precisely and correctly,potentially reshaping our overall language testing practice.Limitations and recommendations for future research were also discussed.展开更多
The genus Caragana is a member of the family of Fabaceae, subfamily Faboideae and there are 62 species, 9 varieties, 12 deformations grown in China. More than 200 components have been identified as flavonoids, stilben...The genus Caragana is a member of the family of Fabaceae, subfamily Faboideae and there are 62 species, 9 varieties, 12 deformations grown in China. More than 200 components have been identified as flavonoids, stilbenoids, which are the major constituents of this genus, and phenylpropanoids, terpenoids, alkaloids also have been isolated from this genus. Modern pharmacological studies suggest diverse pharmacological activities of the herbals from the genus, including anti-tumor, antiinflammatory, anti-virus, and anti-oxidant activities. This review summarized the update research progress on the chemical components and pharmacological effects of the Cragana genus.展开更多
Efficient immune responses rely on the proper differentiation of CD8^(+)T cells into effector and memory cells.Here,we show a critical requirement of N^6-Methyladenosine(m^(6)A)methyltransferase Mettl3 during CD8^(+)T...Efficient immune responses rely on the proper differentiation of CD8^(+)T cells into effector and memory cells.Here,we show a critical requirement of N^6-Methyladenosine(m^(6)A)methyltransferase Mettl3 during CD8^(+)T cell responses upon acute viral infection.Conditional deletion of Mettl3 in CD8^(+)T cells impairs effector expansion and terminal differentiation in an m^(6)A-dependent manner,subsequently affecting memory formation and the secondary response of CD8^(+)T cells.Our combined RNA-seq and m^(6)AmiCLIP-seq analyses reveal that Mettl3 deficiency broadly impacts the expression of cell cycle and transcriptional regulators.Remarkably,Mettl3 binds to the Tbx21 transcript and stabilizes it,promoting effector differentiation of CD8^(+)T cells.Moreover,ectopic expression of T-bet partially restores the defects in CD8^(+)T cell differentiation in the absence of Mettl3.Thus,our study highlights the role of Mettl3 in regulating multiple target genes in an m^(6)A-dependent manner and underscores the importance of m^(6)A modification during CD8^(+)T cell response.展开更多
Delayed diabetic wound healing has placed an enormous burden on society.The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis.Platelet-rich plasma(PRP)gel,a popular biomateri...Delayed diabetic wound healing has placed an enormous burden on society.The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis.Platelet-rich plasma(PRP)gel,a popular biomaterial in the field of regeneration,has limited applications due to its non-injectable properties and rapid release and degradation of growth factors.Here,we prepared an injectable hydrogel(DPLG)based on PRP and laponite by a simple one-step mixing method.Taking advantages of the non-covalent interactions,DPLG could overcome the limitations of PRP gels,which is injectable to fill irregular injures and could serve as a local drug reservoir to achieve the sustained release of growth factors in PRP and deferoxamine(an angiogenesis promoter).DPLG has an excellent ability in accelerating wound healing by promoting macrophage polarization and angiogenesis in a full-thickness skin defect model in typeⅠdiabetic rats and normal rats.Taken together,this study may provide the ingenious and simple bioactive wound dressing with a superior ability to promote wound healing.展开更多
The Integrator complex,discovered in 2005 while searching for protein partners of deleted in split hand/split foot protein 1(DSS1),is the exclusive large multiprotein complex associated with RNA PolⅡthat is specific ...The Integrator complex,discovered in 2005 while searching for protein partners of deleted in split hand/split foot protein 1(DSS1),is the exclusive large multiprotein complex associated with RNA PolⅡthat is specific to metazoans[1].展开更多
基金Foundation of National Natural Science Foundation of China(62202118)Scientific and Technological Research Projects from Guizhou Education Department([2023]003)+1 种基金Guizhou Provincial Department of Science and Technology Hundred Levels of Innovative Talents Project(GCC[2023]018)Top Technology Talent Project from Guizhou Education Department([2022]073).
文摘The development of technologies such as big data and blockchain has brought convenience to life,but at the same time,privacy and security issues are becoming more and more prominent.The K-anonymity algorithm is an effective and low computational complexity privacy-preserving algorithm that can safeguard users’privacy by anonymizing big data.However,the algorithm currently suffers from the problem of focusing only on improving user privacy while ignoring data availability.In addition,ignoring the impact of quasi-identified attributes on sensitive attributes causes the usability of the processed data on statistical analysis to be reduced.Based on this,we propose a new K-anonymity algorithm to solve the privacy security problem in the context of big data,while guaranteeing improved data usability.Specifically,we construct a new information loss function based on the information quantity theory.Considering that different quasi-identification attributes have different impacts on sensitive attributes,we set weights for each quasi-identification attribute when designing the information loss function.In addition,to reduce information loss,we improve K-anonymity in two ways.First,we make the loss of information smaller than in the original table while guaranteeing privacy based on common artificial intelligence algorithms,i.e.,greedy algorithm and 2-means clustering algorithm.In addition,we improve the 2-means clustering algorithm by designing a mean-center method to select the initial center of mass.Meanwhile,we design the K-anonymity algorithm of this scheme based on the constructed information loss function,the improved 2-means clustering algorithm,and the greedy algorithm,which reduces the information loss.Finally,we experimentally demonstrate the effectiveness of the algorithm in improving the effect of 2-means clustering and reducing information loss.
基金supported by the National Natural Science Foundation of China(32072145)。
文摘Trimethylamine N-oxide(TMAO)is a risk factor of various chronic diseases,which was produced by metabolism from precursors to trimethylamine(TMA)in gut and the oxidation from TMA in liver.The TMA generation was influenced by diet,mainly due to the rich TMAO precursors in diet.However,it was still unclear that the effects of different proportion and source of macronutrients in different dietary pattern on the production process of TMAO.Here,the generation of TMA from precursors and TMAO from TMA was determined after single oral choline chloride and intraperitoneal injection TMA,respectively,in mice fed with carbohydrates,proteins and fats in different proportion and sources.The results suggested that the generation of TMAO was increased by low non-meat protein and high fat via enhancing the production of TMAO from TMA,and decreased by plant protein and refined sugar via reducing TMA production from precursors in gut and TMAO transformation from TMA in liver.The high fat and high sugar diets accelerating the development of atherosclerosis did not increase the production of TMAO,the risk factor for atherosclerosis,which indicated that the dietary compositions rather than the elevated TMAO level might be a more key risk factor for atherosclerosis.
文摘Sea cucumber saponins have attracted more attention in recent years due to biological activities.It is a popular practice to soak sea cucumber in Baijiu at home and being applied to industrial manufacturing in China.However,knowledge of the effect of alcohol on the absorption and metabolism of sea cucumber saponins is limited.The effects of alcohol on digestion,absorption and metabolism of sea cucumber saponins in BALB/c mice were investigated after gavage and tail intravenous injection.The results showed that the content of saponins in serum and liver was significantly higher under the influence of alcohol than that in the control group after oral administration.Alcohol promoted the absorption of sea cucumber saponins prototype as well as inhibited the process of saponins being transformed into deglycositic metabolites in the small intestine.Moreover,sea cucumber saponins remained in circulation for a long time and alcohol slowed down the clearance of sea cucumber saponins under the influence of alcohol after intravenous injection.This confirmed the feasibility of marinating sea cucumber in Baijiu to improve the efficacy of saponins and provides an important theoretical basis for the utilization of sea cucumber and the development of sea cucumber liquor.
基金supported by the National Key R&D Program of China(Grant No.2019YFA0308700)the National Natural Science Foundation of China(Grant Nos.11890704,92365107,and 12305020)+2 种基金the Program for Innovative Talents and Teams in Jiangsu(Grant No.JSSCTD202138)the Shccig-Qinling Program,the China Postdoctoral Science Foundation(Grant No.2023M731613)the Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2023ZB708)。
文摘Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonreciprocal devices rely on a strong magnetic field,which is provided by a permanent magnet.As a result,the isolation direction of such devices is fixed and severely restricts their applications in quantum networks.In this work,we experimentally demonstrate the simultaneous one-way transmission and unidirectional reflection by using a magneto-optical Fabry-Pérot cavity and a magnetic field strength of 50 mT.An optical isolator and a three-port quasi-circulator are realized based on this nonreciprocal cavity system.The isolator achieves an isolation ratio of up to 22 dB and an averaged insertion loss down to 0.97 dB.The quasi-circulator is realized with a fidelity exceeding 99% and an overall survival probability of 89.9%,corresponding to an insertion loss of~0.46 dB.The magnetic field is provided by an electromagnetic coil,thereby allowing for reversing the light circulating path.The reversible quasi-circulator paves the way for building reconfigurable quantum networks.
文摘A massive rock and ice avalanche occurred on the western slope of the Ronti Gad valley in the northern part of Chamoli,Indian Himalaya,on 7 February 7,2021.The avalanche on the high mountain slope at an elevation of 5600 m above sea level triggered a long runout disaster chain,including rock mass avalanche,debris avalanche,and flood.The disaster chain had a horizontal travel distance of larger than 17,600 m and an elevation difference of 4300 m.In this study,the disaster characteristics and dynamic process were analyzed by multitemporal satellite imagery.The results show that the massive rock and ice avalanche was caused by four large expanding discontinuity planes.The disaster chain was divided into five zones by satellite images and field observation,including source zone,transition zone,dynamic entrainment zone,flow deposition zone,and flood zone.The entrainment effect and melting water were recognized as the main causes of the long-runout distance.Based on the seismic wave records and field videos,the time progress of the disaster was analyzed and the velocity of frontal debris at different stages was calculated.The total analyzed disaster duration was 1247 s,and the frontal debris velocity colliding with the second hydropower station was approximately 23 m/s.This study also carried out the numerical simulation of the disaster by rapid mass movement simulation(RAMMS).The numerical results reproduced the dynamic process of the debris avalanche,and the mechanism of long-runout avalanche was further verified by parametric study.Furthermore,this study discussed the potential causes of disaster and flood and the roles of satellite images and seismic networks in the monitoring and early-warning.
基金supported by Innovation Talents Promotion Program of Shaanxi Province,China(No.2021TD08)。
文摘Radio frequency fingerprinting(RFF)is a remarkable lightweight authentication scheme to support rapid and scalable identification in the internet of things(IoT)systems.Deep learning(DL)is a critical enabler of RFF identification by leveraging the hardware-level features.However,traditional supervised learning methods require huge labeled training samples.Therefore,how to establish a highperformance supervised learning model with few labels under practical application is still challenging.To address this issue,we in this paper propose a novel RFF semi-supervised learning(RFFSSL)model which can obtain a better performance with few meta labels.Specifically,the proposed RFFSSL model is constituted by a teacher-student network,in which the student network learns from the pseudo label predicted by the teacher.Then,the output of the student model will be exploited to improve the performance of teacher among the labeled data.Furthermore,a comprehensive evaluation on the accuracy is conducted.We derive about 50 GB real long-term evolution(LTE)mobile phone’s raw signal datasets,which is used to evaluate various models.Experimental results demonstrate that the proposed RFFSSL scheme can achieve up to 97%experimental testing accuracy over a noisy environment only with 10%labeled samples when training samples equal to 2700.
基金Project supported by the National Natural Science Foundation of China (Grant No. 62263005)Guangxi Natural Science Foundation (Grant No. 2020GXNSFDA238029)+2 种基金Laboratory of AI and Information Processing (Hechi University), Education Department of Guangxi Zhuang Autonomous Region (Grant No. 2022GXZDSY004)Innovation Project of Guangxi Graduate Education (Grant No. YCSW2023298)Innovation Project of GUET Graduate Education (Grant Nos. 2022YCXS149 and 2022YCXS155)。
文摘This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzzy model. To save the network communication burden, a distributed dynamic event-triggered mechanism is developed to restrain the information update. Besides, random packet dropouts following the Bernoulli distribution are assumed to occur in sensor to controller channels, where the triggered control input is analyzed via an equivalent method containing a new stochastic variable. By establishing the mode-dependent Lyapunov–Krasovskii functional with augmented terms, the finite-time boundness of the error system limited to strict dissipativity is studied. As a result of the help of an extended reciprocally convex matrix inequality technique, less conservative criteria in terms of linear matrix inequalities are deduced to calculate the desired control gains. Finally, two examples in regard to practical systems are provided to display the effectiveness of the proposed theory.
基金This work was supported by the University of Science and Technology Beijing.DG acknowledges the financial support from 111 Project(no.B170003)Foshan Science and Technology Innovation Project(no.2018IT100363).
文摘Electrochemical CO_(2)reduction to C_(2)H_(4)can provide a sustainable route to reduce globally accelerating CO_(2)emissions and produce energy-rich chemical feedstocks.However,the poor selectivity in C_(2)H_(4)electrosynthesis limits its implementation in industrially interesting processes.Herein,we report a composite structured catalyst composed of Ag and Cu_(2)O with different crystal faces to achieve highly efficient reduction of CO_(2)to C_(2)H_(4).The catalyst composed of Ag and octahedral Cu_(2)O enclosed with(111)facet exhibits the best CO_(2)electroreduction performance,with the Faradaic efficiency(FE)and partial current density reaching 66.8%and 17.8 mA cm2 for C_(2)H_(4)product at-1.2 VRHE in 0.5 M KHCO_(3),respectively.Physical characterization and electrochemical test analysis indicate that the high selectivity for C_(2)H_(4)product stems from the synergistic effect of crystal faces control engineering and tandem catalysis.Specifically,Ag can provide optimal availability of CO intermediate by suppressing hydrogen evolution;subsequently,C-C coupling is promoted on the intimate surface of Cu_(2)O with facetdependent selectivity.The insights gained from this work may be beneficial for designing efficient multicomponent catalysts for improving the selectivity of electrochemical CO_(2)reduction reaction to generate C2þproducts.
基金This study was supported by the Jiangsu Provincial Health and Family Planning Commission(WSGL201605)
文摘Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention.
文摘Antarctic krill(Euphausia superba)oil has been gaining increasing attention due to its nutritional and functional potentials.Krill oil usually contains a high concentration(about 50%)of phospholipids(AKOP)rich in DHA and EPA accompanied with 30%–40%triacylglycerols.Phospholipids can be made into liposomes without emulsifiers due to its amphiphilic characteristics.However,the absorption kinetics of AKOP liposome in vivo is not clear,which restrict the molecular mechanism analysis related to its distinct bioactivities.The lipid analysis in serum,small intestinal content and wall was carried out after oral administration of AKOP liposome to illustrate its absorption kinetics in blood and the digestive tract of healthy mice by single gavage.The major type of the obtained AKOP was phosphatidylcholine,and the total contents of the DHA and EPA were 29.31%.AKOP liposome was almost completely digested in the small intestine in 1 h and the hydrolysis products could be quickly absorbed by intestinal enterocytes.The DHA in serum peaked at 2 h after administration of AKOP liposome.AKOP liposome could be quickly digested and absorbed in vivo.The obtained results might provide a scientific basis for the molecular mechanism analysis related to distinct bioactivities of Antarctic krill oil phospholipid.
基金Project supported by the Information Program of the Chinese Academy of Sciences(Grant No.XXH13506-202)
文摘Topological materials have novel properties both in their bulk and boundaries,thereby attracting a wide interest in the theoretical and experimental communities.The recent development of the topological quantum chemistry and symmetrybased indicator theory in this field has significantly simplified the procedure for determining the topological properties of nonmagnetic crystalline materials.Accordingly,a large number of new topological materials have been found by scanning large crystal databases.This study provides details on the algorithm used in the Catalogue of Topological Electronic Materials.Moreover,based on the algorithm,we develop an automatic package named SymTopo,which calculates the symmetry representations of any given nonmagnetic crystalline material and predicts its topological properties.This package may facilitate the discovery of more topological materials in the future.
基金Foundation item:The National Key R&D Program of China under contract No.2018YFD0901500the National Natural Science Foundation of China under contract Nos 41706147 and 41876124.
文摘Cadmium(Cd)is a common heavy metal pollutant in the aquatic environment,generally toxic to plant growth and leading to growth inhibition and biomass reduction.To study the oxidation resistance in Sargassum fusiforme seedlings in response to inorganic Cd stress,we cultured the seedlings under two different Cd levels:natural seawater and high Cd stress.High Cd stress significantly inhibited the seedlings growth,and darkened the thalli color.Additionally,the pigment contents,growth rate,peroxidase(POD)activity,dehydroascorbic acid(DHA)content,and glutathione reductase(GR)activity in S.fusiforme were significantly reduced by high Cd treatment.Contrarily,the Cd accumulation,Cd2+absorption rate,dark respiration/net photosynthetic rate(Rd/Pn),ascorbic acid(Vc)content,soluble protein(SP)content,glutathione(GSH),and the activities of superoxide dismutase(SOD)and catalase(CAT)of S.fusiforme under Cd treatment significantly increased compared to the control group.The decrease of malondialdehyde(MDA)was not significant.Although S.fusiforme seedlings increased the antioxidant activities of POD,SOD,Vc,and the AsA-GSH cycle to disseminate H2O2 and maintain healthy metabolism,high Cd stress caused Cd accumulation in the stem and leaves of S.fusiforme seedlings.The excessive Cd significantly restricted photosynthesis and reduced photosynthetic pigments in the seedlings,resulting in growth inhibition and deep morphological color,especially of the stems.High levels of Cd in seawater had toxic effects on commercial S.fusiforme seedlings,and risked this edible seaweed for human food.
文摘The use of multiple-choice(MC)question types has been one of the most contentious issues in language testing.Much has been said and written about the use of MC over the years.However,no attempt has ever been made to introduce any innovation in test item types.The researchers proposed a jumbled words test item(JW)based on cognitive science and deep learning principles,and addressed the feasibility of replacing the type of multiple-choice(MC)question with JW to meet the ongoing rapid development of language testing practice.Two research questions were proposed ad hoc,focusing on the co-relationship between JW and MC scores.RASCH-GZ was used to perform item analyses(Rasch,1960).The item difficulty parameters thus obtained were used to compare the two different test items.The sample data metric includes 40 Chinese participants.The findings revealed that correlation analysis revealed that the performance of the same group of subjects taking both JW and MC was not relevant(Pearson Corr=0).This is primarily due to the total elimination of guessing factors inherent in test-takers during JW test performance.Three factors were specified for the design of the JW test:compute program,test difficulty,and score acceptability.These all have three dimensions.Data collected through questionnaires were analyzed using EFA in SPSS V.24.0.KMOs(=0.867)were found to be approximately one and significance at 0.000(0.05),indicating that the construct of theuestionnaire thus designed has better validity for factor analysis.Three important conclusions were obtained,the implications of which could provide impetus for our testing counterparts to practice more precisely and correctly,potentially reshaping our overall language testing practice.Limitations and recommendations for future research were also discussed.
文摘The genus Caragana is a member of the family of Fabaceae, subfamily Faboideae and there are 62 species, 9 varieties, 12 deformations grown in China. More than 200 components have been identified as flavonoids, stilbenoids, which are the major constituents of this genus, and phenylpropanoids, terpenoids, alkaloids also have been isolated from this genus. Modern pharmacological studies suggest diverse pharmacological activities of the herbals from the genus, including anti-tumor, antiinflammatory, anti-virus, and anti-oxidant activities. This review summarized the update research progress on the chemical components and pharmacological effects of the Cragana genus.
基金the National Natural Science Foundation of China(32130039,31970831,81970541,31960151,and 31630038)the National Key Research and Development Program of China(2017YFA0104401)+3 种基金the Pinduoduo-China Agricultural University Research Fund(PC2023B01011)Frontiers Science Center for Molecular Design Breeding(MOE),Chinese Universities Scientific Fund(2022TC030 and 2021TC087)the Project for Extramural Scientists of State Key Laboratory of Agrobiotechnology from China Agricultural University(2021SKLAB6-3 and 2021SKLAB6-4)the Collaborative Innovation Center of Chinese Ministry of Education(2020-39)。
文摘Efficient immune responses rely on the proper differentiation of CD8^(+)T cells into effector and memory cells.Here,we show a critical requirement of N^6-Methyladenosine(m^(6)A)methyltransferase Mettl3 during CD8^(+)T cell responses upon acute viral infection.Conditional deletion of Mettl3 in CD8^(+)T cells impairs effector expansion and terminal differentiation in an m^(6)A-dependent manner,subsequently affecting memory formation and the secondary response of CD8^(+)T cells.Our combined RNA-seq and m^(6)AmiCLIP-seq analyses reveal that Mettl3 deficiency broadly impacts the expression of cell cycle and transcriptional regulators.Remarkably,Mettl3 binds to the Tbx21 transcript and stabilizes it,promoting effector differentiation of CD8^(+)T cells.Moreover,ectopic expression of T-bet partially restores the defects in CD8^(+)T cell differentiation in the absence of Mettl3.Thus,our study highlights the role of Mettl3 in regulating multiple target genes in an m^(6)A-dependent manner and underscores the importance of m^(6)A modification during CD8^(+)T cell response.
基金supported by funds from National Natural Science Foundation of China(82173760,32101144,China)Program for HUST Academic Frontier Youth Team(2018QYTD13,China)。
文摘Delayed diabetic wound healing has placed an enormous burden on society.The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis.Platelet-rich plasma(PRP)gel,a popular biomaterial in the field of regeneration,has limited applications due to its non-injectable properties and rapid release and degradation of growth factors.Here,we prepared an injectable hydrogel(DPLG)based on PRP and laponite by a simple one-step mixing method.Taking advantages of the non-covalent interactions,DPLG could overcome the limitations of PRP gels,which is injectable to fill irregular injures and could serve as a local drug reservoir to achieve the sustained release of growth factors in PRP and deferoxamine(an angiogenesis promoter).DPLG has an excellent ability in accelerating wound healing by promoting macrophage polarization and angiogenesis in a full-thickness skin defect model in typeⅠdiabetic rats and normal rats.Taken together,this study may provide the ingenious and simple bioactive wound dressing with a superior ability to promote wound healing.
基金supported by the National Natural Science Foundation of China(32288102)the New Cornerstone Science Laboratory。
文摘The Integrator complex,discovered in 2005 while searching for protein partners of deleted in split hand/split foot protein 1(DSS1),is the exclusive large multiprotein complex associated with RNA PolⅡthat is specific to metazoans[1].
