We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain.The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6×His tags ...We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain.The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6×His tags at the C-and N-termini,respectively.High-level expression of the lipase in E.coli BL21(DE3)was obtained upon induction with IPTG at 20°C.The recombinant lipase activity was approximately 1631-fold higher than the wild type.His-tagged recombinant lipase was purified rapidly and efficiently by using Ni-charged affinity chromatography with 63.5%recovery and a purification factor of 10.78.The purified lipase was stable in a broad range of temperatures and pH values,with the optimal temperature and pH being 50°C and 7.0,respectively.Its activity was stimulated to different degrees in the presence of metal ions such as Ca2+,Mg2+,and some non-ionic surfactants.In addition,the purified lipase was activated by a series of water-miscible organic solvents such as some short carbon chain alcohols and was highly tolerant to some water-immiscible organic solvents.展开更多
Credit card fraud is a wide-ranging issue for financial institutions, involving theft and fraud committed using a payment card. In this paper, we explore the application of linear and nonlinear statistical modeling an...Credit card fraud is a wide-ranging issue for financial institutions, involving theft and fraud committed using a payment card. In this paper, we explore the application of linear and nonlinear statistical modeling and machine learning models on real credit card transaction data. The models built are supervised fraud models that attempt to identify which transactions are most likely fraudulent. We discuss the processes of data exploration, data cleaning, variable creation, feature selection, model algorithms, and results. Five different supervised models are explored and compared including logistic regression, neural networks, random forest, boosted tree and support vector machines. The boosted tree model shows the best fraud detection result (FDR = 49.83%) for this particular data set. The resulting model can be utilized in a credit card fraud detection system. A similar model development process can be performed in related business domains such as insurance and telecommunications, to avoid or detect fraudulent activity.展开更多
An optical field with sub-nm confinement is essential for exploring atomic-or molecular-level light-matter interaction.While such fields demonstrated so far have typically point-like cross-sections,an optical field ha...An optical field with sub-nm confinement is essential for exploring atomic-or molecular-level light-matter interaction.While such fields demonstrated so far have typically point-like cross-sections,an optical field having a higher-dimensional cross-section may offer higher flexibility and/or efficiency in applications.Here,we propose generating a nanoscale blade-like optical field in a coupled nanofiber pair(CNP)with a 1-nm-width central slit.Based on a strong mode coupling-enabled slit waveguide mode,a sub-nm-thickness blade-like optical field can be generated with a cross-section down to~0.28 nm×38 nm at 1550 nm wavelength(i.e.,a thickness of~λ_(0)∕5000)and a peak-to-background intensity ratio(PBR)higher than 20 d B.The slit waveguide mode of the CNP can be launched from one of the two nanofibers that are connected to a standard optical fiber via an adiabatical fiber taper,in which a fundamental waveguide mode of the fiber can be converted into a high-purity slit mode with high efficiency(>98%)within a CNP length of less than 10μm at 1550 nm wavelength.The wavelengthdependent behaviors and group velocity dispersion in mode converting processes are also investigated,showing that such a CNP-based design is also suitable for broadband and ultrafast pulsed operation.Our results may open up new opportunities for studying light-matter interaction down to the sub-nm scale,as well as for exploring ultra-high-resolution optical technology ranging from super-resolution nanoscopy to chemical bond manipulation.展开更多
Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disease with an estimated worldwide prevalence of 32.4%.1 The multisystem condition is related to an increased risk of liver-related and cardiova...Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disease with an estimated worldwide prevalence of 32.4%.1 The multisystem condition is related to an increased risk of liver-related and cardiovascular extrahepatic diseases.2 Smoking is the leading preventable risk factor for premature disability and mortality.As NAFLD and smoking are both associated with the development of metabolic features,there has been increasing interest in testing the relationship between smoking and NAFLD.The causal relevance of smoking to NAFLD incidence have been implicated in crosssectional and prospective cohort studies.3,4 However,previous studies mainly focused on the effect of active smoking,discussion on the influence of passive smoking on NAFLD will facilitate illustrating the association between smoking and NAFLD.We conducted a national two-center cross-section study of active,passive smoking and NAFLD risk in Chinese and European population.This design allowed us to(1)test for associations between active,passive smoking and NAFLD risk by sex and consolidate evidence for causality by estimating dose-response relationship,(2)identify mediated factors,and(3)resolve their possible interaction with smoking.展开更多
Solving optimal control problems serves as the basic demand of industrial control tasks.Existing methods like model predictive control often suffer from heavy online computational burdens.Reinforcement learning has sh...Solving optimal control problems serves as the basic demand of industrial control tasks.Existing methods like model predictive control often suffer from heavy online computational burdens.Reinforcement learning has shown promise in computer and board games but has yet to be widely adopted in industrial applications due to a lack of accessible,high-accuracy solvers.Current Reinforcement learning(RL)solvers are often developed for academic research and require a significant amount of theoretical knowledge and programming skills.Besides,many of them only support Python-based environments and limit to model-free algorithms.To address this gap,this paper develops General Optimal control Problems Solver(GOPS),an easy-to-use RL solver package that aims to build real-time and high-performance controllers in industrial fields.GOPS is built with a highly modular structure that retains a flexible framework for secondary development.Considering the diversity of industrial control tasks,GOPS also includes a conversion tool that allows for the use of Matlab/Simulink to support environment construction,controller design,and performance validation.To handle large-scale problems,GOPS can automatically create various serial and parallel trainers by flexibly combining embedded buffers and samplers.It offers a variety of common approximate functions for policy and value functions,including polynomial,multilayer perceptron,convolutional neural network,etc.Additionally,constrained and robust algorithms for special industrial control systems with state constraints and model uncertainties are also integrated into GOPS.Several examples,including linear quadratic control,inverted double pendulum,vehicle tracking,humanoid robot,obstacle avoidance,and active suspension control,are tested to verify the performances of GOPS.展开更多
We propose to generate a sub-nanometer-confined optical field in a nanoslit waveguiding mode in a coupled nanowire pair(CNP).We show that,when a conventional waveguide mode with a proper polarization is evanescently c...We propose to generate a sub-nanometer-confined optical field in a nanoslit waveguiding mode in a coupled nanowire pair(CNP).We show that,when a conventional waveguide mode with a proper polarization is evanescently coupled into a properly designed CNP with a central nanoslit,it can be efficiently channeled into a high-purity nanoslit mode within a waveguiding length<10μm.The CNP can be either freestanding or on-chip by using a tapered fiber or planar waveguide for input-coupling,with a coupling efficiency up to 95%.Within the slit region,the output diffraction-limited nanoslit mode offers an extremely confined optical field(∼0.3 nm×3.3 nm)with a peak-to-background ratio higher than 25 dB and can be operated within a 200-nm bandwidth.The group velocity dispersion of the nanoslit mode for ultrafast pulsed operation is also briefly investigated.Compared with the previous lasing configuration,the waveguiding scheme demonstrated here is not only simple and straightforward in structural design but is also much flexible and versatile in operation.Therefore,the waveguiding scheme we show here may offer an efficient and flexible platform for exploring light–matter interactions beyond the nanometer scale,and developing optical technologies ranging from superresolution nanoscopy and atom/molecule manipulation to ultra-sensitivity detection.展开更多
To study the function of CaPpt1,we deleted PPT1 gene from the Candida albicans genome by sequentially replacing the entire coding region with the selectable markers ARG4 and HIS1.The results showed that the deletion o...To study the function of CaPpt1,we deleted PPT1 gene from the Candida albicans genome by sequentially replacing the entire coding region with the selectable markers ARG4 and HIS1.The results showed that the deletion of Ppt1 did not affect the hyphal formation of C.albicans under serum induction and caused enhanced sensitivity to DNA damage,Calcofluor white and saltinduced stress.We also found that Ppt1 was not required for the phenotypic response of cells treated with the genotoxins,methylmethane sulfonate and hydroxyurea.Flow cytometric analyses indicated that ppt1D cells and wild-type cells showed similar G2/M arrest profiles when exposed to DNA damage stress.Ppt1 was not required for the activation of the DNA damage response pathway,as indicated by normal phosphorylation of Rad53 and Rfa2 in ppt1D cells under DNA damage stress.We suggest that Ppt1 plays important roles in response to various stress conditions in C.albicans.展开更多
文摘We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain.The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6×His tags at the C-and N-termini,respectively.High-level expression of the lipase in E.coli BL21(DE3)was obtained upon induction with IPTG at 20°C.The recombinant lipase activity was approximately 1631-fold higher than the wild type.His-tagged recombinant lipase was purified rapidly and efficiently by using Ni-charged affinity chromatography with 63.5%recovery and a purification factor of 10.78.The purified lipase was stable in a broad range of temperatures and pH values,with the optimal temperature and pH being 50°C and 7.0,respectively.Its activity was stimulated to different degrees in the presence of metal ions such as Ca2+,Mg2+,and some non-ionic surfactants.In addition,the purified lipase was activated by a series of water-miscible organic solvents such as some short carbon chain alcohols and was highly tolerant to some water-immiscible organic solvents.
文摘Credit card fraud is a wide-ranging issue for financial institutions, involving theft and fraud committed using a payment card. In this paper, we explore the application of linear and nonlinear statistical modeling and machine learning models on real credit card transaction data. The models built are supervised fraud models that attempt to identify which transactions are most likely fraudulent. We discuss the processes of data exploration, data cleaning, variable creation, feature selection, model algorithms, and results. Five different supervised models are explored and compared including logistic regression, neural networks, random forest, boosted tree and support vector machines. The boosted tree model shows the best fraud detection result (FDR = 49.83%) for this particular data set. The resulting model can be utilized in a credit card fraud detection system. A similar model development process can be performed in related business domains such as insurance and telecommunications, to avoid or detect fraudulent activity.
基金New Cornerstone Science Foundation(NCI202216)National Natural Science Foundation of China(62175213,92150302)+2 种基金Natural Science Foundation of Zhejiang Province(LR21F050002)Fundamental Research Funds for the Central Universities(2023QZJH27)National Key Research and Development Program of China(2018YFB2200404)。
文摘An optical field with sub-nm confinement is essential for exploring atomic-or molecular-level light-matter interaction.While such fields demonstrated so far have typically point-like cross-sections,an optical field having a higher-dimensional cross-section may offer higher flexibility and/or efficiency in applications.Here,we propose generating a nanoscale blade-like optical field in a coupled nanofiber pair(CNP)with a 1-nm-width central slit.Based on a strong mode coupling-enabled slit waveguide mode,a sub-nm-thickness blade-like optical field can be generated with a cross-section down to~0.28 nm×38 nm at 1550 nm wavelength(i.e.,a thickness of~λ_(0)∕5000)and a peak-to-background intensity ratio(PBR)higher than 20 d B.The slit waveguide mode of the CNP can be launched from one of the two nanofibers that are connected to a standard optical fiber via an adiabatical fiber taper,in which a fundamental waveguide mode of the fiber can be converted into a high-purity slit mode with high efficiency(>98%)within a CNP length of less than 10μm at 1550 nm wavelength.The wavelengthdependent behaviors and group velocity dispersion in mode converting processes are also investigated,showing that such a CNP-based design is also suitable for broadband and ultrafast pulsed operation.Our results may open up new opportunities for studying light-matter interaction down to the sub-nm scale,as well as for exploring ultra-high-resolution optical technology ranging from super-resolution nanoscopy to chemical bond manipulation.
基金supported by the National Natural Science Foundation of China(No.81903382)Natural Science Foundation of Jiangsu Province(Nos.BK20190652,BK20220320)+2 种基金Science and Technology Young Scientific and Technological Talents Project of Jiangsu Province(No.2021-50)China Postdoctoral Science Foundation(Nos.General Program,2019M651900,2021M701757)CAMS Innovation Fund for Medical Sciences(No.2019RU038).
文摘Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disease with an estimated worldwide prevalence of 32.4%.1 The multisystem condition is related to an increased risk of liver-related and cardiovascular extrahepatic diseases.2 Smoking is the leading preventable risk factor for premature disability and mortality.As NAFLD and smoking are both associated with the development of metabolic features,there has been increasing interest in testing the relationship between smoking and NAFLD.The causal relevance of smoking to NAFLD incidence have been implicated in crosssectional and prospective cohort studies.3,4 However,previous studies mainly focused on the effect of active smoking,discussion on the influence of passive smoking on NAFLD will facilitate illustrating the association between smoking and NAFLD.We conducted a national two-center cross-section study of active,passive smoking and NAFLD risk in Chinese and European population.This design allowed us to(1)test for associations between active,passive smoking and NAFLD risk by sex and consolidate evidence for causality by estimating dose-response relationship,(2)identify mediated factors,and(3)resolve their possible interaction with smoking.
基金supported by the National Key R&D Program of China(2022YFB2502901)the Natural Science Foundation of China(U20A20334).
文摘Solving optimal control problems serves as the basic demand of industrial control tasks.Existing methods like model predictive control often suffer from heavy online computational burdens.Reinforcement learning has shown promise in computer and board games but has yet to be widely adopted in industrial applications due to a lack of accessible,high-accuracy solvers.Current Reinforcement learning(RL)solvers are often developed for academic research and require a significant amount of theoretical knowledge and programming skills.Besides,many of them only support Python-based environments and limit to model-free algorithms.To address this gap,this paper develops General Optimal control Problems Solver(GOPS),an easy-to-use RL solver package that aims to build real-time and high-performance controllers in industrial fields.GOPS is built with a highly modular structure that retains a flexible framework for secondary development.Considering the diversity of industrial control tasks,GOPS also includes a conversion tool that allows for the use of Matlab/Simulink to support environment construction,controller design,and performance validation.To handle large-scale problems,GOPS can automatically create various serial and parallel trainers by flexibly combining embedded buffers and samplers.It offers a variety of common approximate functions for policy and value functions,including polynomial,multilayer perceptron,convolutional neural network,etc.Additionally,constrained and robust algorithms for special industrial control systems with state constraints and model uncertainties are also integrated into GOPS.Several examples,including linear quadratic control,inverted double pendulum,vehicle tracking,humanoid robot,obstacle avoidance,and active suspension control,are tested to verify the performances of GOPS.
基金This work was sup-ported by the National Key Research and Development Program of China(2018YFB2200404)the New Cornerstone Science Foundation,the National Natural Science Foundation of China(92150302 and 62175213)+1 种基金the Natural Science Foundation of Zhejiang Province(LR21F050002)the Fundamental Research Funds for the Central Universities.
文摘We propose to generate a sub-nanometer-confined optical field in a nanoslit waveguiding mode in a coupled nanowire pair(CNP).We show that,when a conventional waveguide mode with a proper polarization is evanescently coupled into a properly designed CNP with a central nanoslit,it can be efficiently channeled into a high-purity nanoslit mode within a waveguiding length<10μm.The CNP can be either freestanding or on-chip by using a tapered fiber or planar waveguide for input-coupling,with a coupling efficiency up to 95%.Within the slit region,the output diffraction-limited nanoslit mode offers an extremely confined optical field(∼0.3 nm×3.3 nm)with a peak-to-background ratio higher than 25 dB and can be operated within a 200-nm bandwidth.The group velocity dispersion of the nanoslit mode for ultrafast pulsed operation is also briefly investigated.Compared with the previous lasing configuration,the waveguiding scheme demonstrated here is not only simple and straightforward in structural design but is also much flexible and versatile in operation.Therefore,the waveguiding scheme we show here may offer an efficient and flexible platform for exploring light–matter interactions beyond the nanometer scale,and developing optical technologies ranging from superresolution nanoscopy and atom/molecule manipulation to ultra-sensitivity detection.
基金supported by the National Natural Science Foundation of China(31270113,31300133)the Beijing Natural Science Foundation(5132019)+1 种基金the Fundamental Research Foundation for the Central Universities(105566GK)Open Fund of Key Laboratory of Cell Proliferation and Regulation Biology,Ministry of Education
文摘To study the function of CaPpt1,we deleted PPT1 gene from the Candida albicans genome by sequentially replacing the entire coding region with the selectable markers ARG4 and HIS1.The results showed that the deletion of Ppt1 did not affect the hyphal formation of C.albicans under serum induction and caused enhanced sensitivity to DNA damage,Calcofluor white and saltinduced stress.We also found that Ppt1 was not required for the phenotypic response of cells treated with the genotoxins,methylmethane sulfonate and hydroxyurea.Flow cytometric analyses indicated that ppt1D cells and wild-type cells showed similar G2/M arrest profiles when exposed to DNA damage stress.Ppt1 was not required for the activation of the DNA damage response pathway,as indicated by normal phosphorylation of Rad53 and Rfa2 in ppt1D cells under DNA damage stress.We suggest that Ppt1 plays important roles in response to various stress conditions in C.albicans.
