The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr during heat treatment and its influence on damping and mechanical properties are reported in this work.Prior to heat treatment,the alloy consisted of a-Mg matrix ...The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr during heat treatment and its influence on damping and mechanical properties are reported in this work.Prior to heat treatment,the alloy consisted of a-Mg matrix and lamellar 14H LPSO phases.After 510℃heat treatment,lamellae shortened,and their content decreased.Upon 8h heat treatment,block 18R LPSO phases formed at the grain boundaries while 14H LPSO lamellae disappeared.Presence of block 18R LPSO phases improved mechanical and damping properties of the alloy.The corresponding mechanisms of the influence of LPSO type and morphology on mechanical and damping capacities are discussed.展开更多
BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some ...BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.展开更多
A rapid and sensitive method to identify and analyze mixed pesticides of tricyclazole,paraquat and flusilazole by surface-enhanced Raman scattering has been reported.Aqueous samples can be detected by SERS in low conc...A rapid and sensitive method to identify and analyze mixed pesticides of tricyclazole,paraquat and flusilazole by surface-enhanced Raman scattering has been reported.Aqueous samples can be detected by SERS in low concentrations of 0.01 mg/L, 0.1 mg/L and 2.85 mg/L for individual tricyclazole,paraquat and flusilazole respectively.When mixing the three pesticides in the low concentrations,their characteristic peaks can still be identified from the SERS spectrum of the mixture.展开更多
Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could ex...Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could exert hypoxic stresses such as oxidative damage on organisms living in these environments.In order to cope with these stresses,organisms have evolved specific strategies to adapt to hypoxia,including changes in physiology,gene expression regulation,and genetic mutations.Here,we review how mammals have adapted to the three high-altitude plateaus of the world,the limited oxygen dissolved in deep water habitats,and underground tunnels,with the aim of better understanding the adaptation of mammals to hypoxia.展开更多
Let M be the multilinear maximal function and = （b1, . . . , bm） be a collection of locally integrable functions. Denote by M and [,M] the maximal commutator and the commutator of M with , respectively. In this pape...Let M be the multilinear maximal function and = （b1, . . . , bm） be a collection of locally integrable functions. Denote by M and [,M] the maximal commutator and the commutator of M with , respectively. In this paper, the multiple weighted strong and weak type estimates for operators M and [,M] are studied. Some characterizations of the class of functions bj are given, for which these operators satisfy some strong or weak type estimates.展开更多
Short-chain fatty acids are important nutrients that regulate milk fat synthesis.They regulate milk syn-thesis via the sterol regulatory element binding protein 1(SREBP1)pathway;however,the details are still unknown.H...Short-chain fatty acids are important nutrients that regulate milk fat synthesis.They regulate milk syn-thesis via the sterol regulatory element binding protein 1(SREBP1)pathway;however,the details are still unknown.Here,the regulation and mechanism of sodium acetate(SA)in milk fat synthesis in bovine mammary epithelial cells(BMECs)were assessed.BMECs were treated with SA supplementation(SAþ)or without SA supplementation(SA-),and milk fat synthesis and activation of the SREBP1 pathway were increased(P=0.0045;P=0.0042)by SAþand decreased(P=0.0068;P=0.0031)by SA-,respectively.Overexpression or inhibition of SREBP1 demonstrated that SA promoted milk fat synthesis(P=0.0045)via the SREBP1 pathway.Overexpression or inhibition of TATA element modulatory factor 1(TMF1)demon-strated that TMF1 suppressed activation of the SREBP1 pathway(P=0.0001)and milk fat synthesis(P=0.0022)activated by SAþ.Overexpression or inhibition of TMF1 and SREBP1 showed that TMF1 suppressed milk fat synthesis(P=0.0073)through the SREBP1 pathway.Coimmunoprecipitation analysis revealed that TMF1 interacted with SREBP1 in the cytoplasm and suppressed the nuclear localization of SREBP1(P=0.0066).The absence or presence of SA demonstrated that SA inhibited the expression of TMF1(P=0.0002)and the interaction between TMF1 and SREBP1(P=0.0001).Collectively,our research sug-gested that TMF1 was a new negative regulator of milk fat synthesis.In BMECs,SA promoted the SREBP1 pathway and milk fat synthesis by suppressing TMF1.This study enhances the current understanding of the regulation of milk fat synthesis and provides new scientific data for the regulation of milk fat synthesis.展开更多
The high-pressure behavior of deep carbonate dictates the state and dynamics of oxidized carbon in the Earth's mantle,playing a vital role in the global carbon cycle and potentially influencing long-term climate c...The high-pressure behavior of deep carbonate dictates the state and dynamics of oxidized carbon in the Earth's mantle,playing a vital role in the global carbon cycle and potentially influencing long-term climate change.Optical absorption and Raman spectroscopic measurements were carried out on two natural carbonate samples in diamond-anvil cells up to 60 GPa.Mg-substitution in high-spin siderite FeCO_(3)increases the crystal field absorption band position by approximately 1000 cm^(-1),but such an effect is marginal at>40 GPa when entering the low-spin state.The crystal field absorption band of dolomite cannot be recognized upon compression to 45.8 GPa at room temperature but,in contrast,the high-pressure polymorph of dolomite exhibits a strong absorption band at frequencies higher than(Mg,Fe)CO_(3)in the lowspin state by 2000–2500 cm^(-1).Additionally,these carbonate minerals show more complicated features for the absorption edge,decreasing with pressure and undergoing a dramatic change through the spin crossover.The optical and vibrational properties of carbonate minerals are highly correlated with iron content and spin transition,indicating that iron is preferentially partitioned into low-spin carbonates.These results shed new light on how carbonate minerals evolve in the mantle,which is crucial to decode the deep carbon cycle.展开更多
The aim of software testing is to find faults in a program under test, so generating test data that can expose the faults of a program is very important. To date, current stud- ies on generating test data for path cov...The aim of software testing is to find faults in a program under test, so generating test data that can expose the faults of a program is very important. To date, current stud- ies on generating test data for path coverage do not perform well in detecting low probability faults on the covered path. The automatic generation of test data for both path coverage and fault detection using genetic algorithms is the focus of this study. To this end, the problem is first formulated as a bi-objective optimization problem with one constraint whose objectives are the number of faults detected in the traversed path and the risk level of these faults, and whose constraint is that the traversed path must be the target path. An evolution- ary algorithm is employed to solve the formulated model, and several types of fault detection methods are given. Finally, the proposed method is applied to several real-world programs, and compared with a random method and evolutionary opti- mization method in the following three aspects： the number of generations and the time consumption needed to generate desired test data, and the success rate of detecting faults. The experimental results confirm that the proposed method can effectively generate test data that not only traverse the target path but also detect faults lying in it.展开更多
Generating test data that can expose the faults of the program is an important issue in software testing. Al- though previous methods of covering path can generate test data to traverse target path, the test data gene...Generating test data that can expose the faults of the program is an important issue in software testing. Al- though previous methods of covering path can generate test data to traverse target path, the test data generated by these methods are difficult in detecting some low-probabilistic faults that lie on the covered paths. We present a method of generating test data for covering multiple paths to detect faults in this study. First, we transform the problem of cover- ing multiple paths and detecting faults into a multi-objective optimization problem with constraint, and construct a mathe- matical model for it. Then, we give a strategy of solving the model based on a weighted genetic algorithm. Finally, we ap- ply our method to several real-world programs, and compare it with several methods. The experimental results confirm that the proposed method can more efficiently generate test data that not only traverse the target paths but also detect faults lying in them than other methods.展开更多
Mn-based oxides have been regarded as a promising family of cathode materials for high-performance lithium-ion batteries,but the practical applications have been limited because of severe capacity deterioration(such a...Mn-based oxides have been regarded as a promising family of cathode materials for high-performance lithium-ion batteries,but the practical applications have been limited because of severe capacity deterioration(such as Li Mn O_(2)and Li Mn_(2)O_(4))as well as further complications from successive structure changes during cycling,low initial coulombic efficiency(such as Li-rich cathode)and oxidization of organic carbonate solvents at high charge potential(such as Li Ni0.5 Mn1.5 O4).Large amounts of efforts have been concentrated on resolving these issues towards practical applications,and many vital progresses have been carried out.Hence,the primary target of this review is focused on different proposed strategies and breakthroughs to enhance the rate performance and cycling stability of nanostructured Mn-based oxide cathode materials for Li-ion batteries,including morphology control,ion doping,surface coatings,composite construction.The combination of delicate architectures with conductive species represents the perspective ways to enhance the conductivity of the cathode materials and further buffer the structure transformation and strain during cycling.At last,based on the elaborated progress,several perspectives of Mn-based oxide cathodes are summarized,and some possible attractive strategies and future development directions of Mn-based oxide cathodes with enhanced electrochemical properties are proposed.The review will offer a detailed introduction of various strategies enhancing electrochemical performance and give a novel viewpoint to shed light on the future innovation in Mn-based oxide cathode materials,which benefits the design and construction of high-performance Mn-based oxide cathode materials in the future.展开更多
Let 6=(bi,b2,...,bm)be a collection of locally integrable functions and T,the com-mutator of multilinear singular integral operator T.Denote by L(δ)and L(δ(·))the Lipschitz spaces and the variable Lipschitz spa...Let 6=(bi,b2,...,bm)be a collection of locally integrable functions and T,the com-mutator of multilinear singular integral operator T.Denote by L(δ)and L(δ(·))the Lipschitz spaces and the variable Lipschitz spaces,respectively.The main purpose of this paper is to establish some new characterizations of the(variable)Lipschitz spaces in terms of the boundedness of multilinear commutator T∑b in the context of the variable exponent Lebesgue spaces,that is,the authors give the necessary and sufficient conditions for bj(j=1,2,...,m)to be L(δ)or L(δ(·))via the boundedness of multilinear commutator from products of variable exponent Lebesgue spaces to variable exponent Lebesgue spaces.The authors do so by applying the Fourier series technique and some pointwise esti-mate for the commutators.The key tool in obtaining such pointwise estimate is a certain generalization of the classical sharp maximal operator.展开更多
Based on the adsorption of copper ions on single-walled carbon nanotubes（SWNTs） in electrolyte, Cu/SWNTs nanocomposite film was initially prepared on indium-doped tin oxide（ITO） substrate by one-step electrodeposi...Based on the adsorption of copper ions on single-walled carbon nanotubes（SWNTs） in electrolyte, Cu/SWNTs nanocomposite film was initially prepared on indium-doped tin oxide（ITO） substrate by one-step electrodeposition. This method may provide a versatile and facile pathway to fabricate other SWNTs-supported metal composite films. Electrochemical experiments revealed that the obtained Cu/SWNTs/ITO electrode offered an excellent electrocatalytic activity towards the oxidation of glucose and could be applied to the construction of non-enzymatic glucose biosensor. The linear range of the sensor was 1.0×10–6 to 6.0×10–4 mol/L and the response time was within 2 s. Particularly, its sensitivity reached as high as 1434.67 μA？L？mmol–1？cm–2, which was superior to any other non-enzymatic glucose biosensor based on copper-carbon nanotubes electrode reported previously.展开更多
Diamond-like carbon (DLC) films were prepared by PLD process using 308 nm(XeCl) laser beam with high power (500 W) and high frequency(300 Hz). The effects of nitrogen pressure on the structure and properties of the DL...Diamond-like carbon (DLC) films were prepared by PLD process using 308 nm(XeCl) laser beam with high power (500 W) and high frequency(300 Hz). The effects of nitrogen pressure on the structure and properties of the DLC films under such extremely high power and repetition rate were studied. The results indicate that the microstructures of the films are varied from amorphous carbon to graphitized carbon in long-order with the increase of N2 pressure, and the optical properties of the films are deteriorated as compared to that of DLC films without nitrogen.展开更多
Compound ceramic coatings with the main crystalline of Al_2TiO_5（in the as-prepared coating without treatment） were prepared in situ on the surface Ti-6Al-4V alloy by means of pulsed bipolar micro-arc oxidation in N...Compound ceramic coatings with the main crystalline of Al_2TiO_5（in the as-prepared coating without treatment） were prepared in situ on the surface Ti-6Al-4V alloy by means of pulsed bipolar micro-arc oxidation in Na AlO_2 solution. For the purpose of studying the antioxidation properties of the samples, the coated samples treated in argon and the as-coated samples were calcined in air at 1000 °C. And the related characteristics were investigated by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and X-ray fluorescence（XRF） spectroscopy, respectively. The results show that, when it was calcined in air for 1 h, Al_2TiO_5in the as-prepared coating decomposed and transformed into α-Al_2O_3 and rutile TiO_2.However, after almost 4 h in argon, Al_2TiO_5in the asprepared coating decomposed and the final coating surface contents are completely α-Al_2O_3, and those of the middle interface are mainly Al_2O_3 and Ti_2O_3. The morphologies of the coatings after calcination in argon and air are different.High-temperature oxidation occurred violently in the alloy substrate without coatings. Furthermore, the weight gain curves of the as-prepared samples and the coated samples treated in argon both show a parabolic shape.展开更多
1 Introduction Regression testing refers to retest code after modification to ensure that changes will not introduce new faults or cause faults in other lines of code[1].Regression test selection(RTS)is one of the pre...1 Introduction Regression testing refers to retest code after modification to ensure that changes will not introduce new faults or cause faults in other lines of code[1].Regression test selection(RTS)is one of the predominant techniques.It identifies test cases that are relevant to test recent changes in an application and seeks to reduce the number of test suite while preserving the capability to reveal faults[2].展开更多
Density functional theory (DFT) calculations were carried out to investigate the organic field effect transistor (OFET) performance of the symmetrical metal-free tetrakis (1,2,5-thiadiazole) porphyrazine (S4)PzH2 and ...Density functional theory (DFT) calculations were carried out to investigate the organic field effect transistor (OFET) performance of the symmetrical metal-free tetrakis (1,2,5-thiadiazole) porphyrazine (S4)PzH2 and tetrakis (1,4-diamyloxybenzene) (A4)PzH2 as well as the low-symmetry metal-free porphy- razine with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene groups in the ratio 2:2 (cis) and 1:3, that is, (cis-S2A2)PzH2 and (SA3)PzH2, (S = 1,2,5-thiadiazole ring, A = annulated 1,4-diamyloxy-benzene ring, Pz = porphyrazine) in terms of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy, ionization energy (IE), electron affinity (EA), and their reorganization energy (λ) during the charge-transport process. On the basis of Marcus electron transfer theory, electronic couplings (V) and field effect transistor (FET) properties for the four compounds with known crystal structure have been calculated. The electron transfer mobility (μ -) is revealed to be 0.056 cm2·V-1·s-1 for (S4)PzH2. The hole transfer mobility (μ+) is 0.075, 0.098, and 8.20 cm2·V-1·s-1 for (cis-S2A2)PzH2, (SA3)PzH2, and (A4)PzH2, respectively. The present work represents the theoretical effort towards understanding the OFET properties of symmetrical and unsymmetrical porphyrazine derivatives with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene.展开更多
The stereo matching method based on a space-aware network is proposed, which divides the network into threesections: Basic layer, scale layer, and decision layer. This division is beneficial to integrate residue netwo...The stereo matching method based on a space-aware network is proposed, which divides the network into threesections: Basic layer, scale layer, and decision layer. This division is beneficial to integrate residue network and densenetwork into the space-aware network model. The vertical splitting method for computing matching cost by usingthe space-aware network is proposed for solving the limitation of GPU RAM. Moreover, a hybrid loss is broughtforward to boost the performance of the proposed deep network. In the proposed stereo matching method, thespace-aware network is used to calculate the matching cost and then cross-based cost aggregation and semi-globalmatching are employed to compute a disparity map. Finally, a disparity-post processing method is utilized suchas subpixel interpolation, median filter, and bilateral filter. The experimental results show this method has a goodperformance on running time and accuracy, with a percentage of erroneous pixels of 1.23% on KITTI 2012 and1.94% on KITTI 2015.展开更多
To solve the teaching difficulties,including hard cultivating engineering thinking,a reasonable transition of professional training,and deep cooperation of students,which impeded the cultivation effectiveness of stude...To solve the teaching difficulties,including hard cultivating engineering thinking,a reasonable transition of professional training,and deep cooperation of students,which impeded the cultivation effectiveness of students’ability to solve complex engineering problems,the paper proposed a Zongheng group teaching model of curriculum cluster based on projects.Firstly,from the perspective of Metaverse,and considering the professional,current teaching situation and learning situation,we analyzed the professional background and proposed the Zongheng group teaching model of curriculum cluster.Then,the connotation,teaching construction and implementation details are explained.After that,we summarized the teaching effect about the 2 years of exploration and practice in the major of software engineering at College of Computer and Information Technology in Mudanjiang Normal University,to clarify the effect of teaching reform.2 years of teaching practice shows that making full use of the advantages of curriculum cluster,Zongheng group and the project-based teaching method,the long-range training,in-depth student cooperation,and the students’ability of solving complex engineering problems are improved.展开更多
In this paper, we conduct research on the development of Daur ethnic education under the influence of big data. Life in the river valley of Daur ethnic which is a nationality has a long history, splendid culture and t...In this paper, we conduct research on the development of Daur ethnic education under the influence of big data. Life in the river valley of Daur ethnic which is a nationality has a long history, splendid culture and the national spirit of national self-confidence, the foundation of national culture has a strong self-confidence. Combining the concept of big data and data analysis technique to the Daur ethnic education will largely enhance the result of the current education pattern. The survey of the research indicated that we should pay attention to the precious data captured.展开更多
基金This paper was supported by National Natural Science Foundation of China(51671063,51771060,51871068,51971071)Domain Foundation of Equipment Advance Research of 13th Five-year Plan(61409220118)+3 种基金Heilongjiang Province Natural Science Foundation(LH2019E081,E2017030)the Fundamental Research Funds for the Central Universities(HEUCFG201834)Harbin City Application Technology Research and Development Project(2017RAQXJ032)Project of Mudanjiang normal university(GP2020004).
文摘The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr during heat treatment and its influence on damping and mechanical properties are reported in this work.Prior to heat treatment,the alloy consisted of a-Mg matrix and lamellar 14H LPSO phases.After 510℃heat treatment,lamellae shortened,and their content decreased.Upon 8h heat treatment,block 18R LPSO phases formed at the grain boundaries while 14H LPSO lamellae disappeared.Presence of block 18R LPSO phases improved mechanical and damping properties of the alloy.The corresponding mechanisms of the influence of LPSO type and morphology on mechanical and damping capacities are discussed.
基金The Shanxi Provincial Administration of Traditional Chinese Medicine,No.2023ZYYDA2005.
文摘BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.
基金supported by the National Natural Science Foundation of China(No.20975039)Yantai Science and Technology Bureau(No.2010145)
文摘A rapid and sensitive method to identify and analyze mixed pesticides of tricyclazole,paraquat and flusilazole by surface-enhanced Raman scattering has been reported.Aqueous samples can be detected by SERS in low concentrations of 0.01 mg/L, 0.1 mg/L and 2.85 mg/L for individual tricyclazole,paraquat and flusilazole respectively.When mixing the three pesticides in the low concentrations,their characteristic peaks can still be identified from the SERS spectrum of the mixture.
基金This work was financially supported by the National Key R&D Program of China(2021YFB3802200)the Scientific and Technological Innovation Foundation of Shunde Graduate School,University of Science and Technology Beijing(BK19AE027 and BK20BE022).
基金Doctoral Research Fund of Mudanjiang Teachers College,Grant/Award Number:No.1002319042The filing project of Heilongjiang Education Department,Grant/Award Number:1354MSYTD024Ancell-Teicher Research Foundation for Genetic and Molecular Evolution.
文摘Oxygen plays a pivotal role in the metabolism and activities of mammals.However,oxygen is restricted in some environments-subterranean burrow systems or habitats at high altitude or deep in the ocean-and this could exert hypoxic stresses such as oxidative damage on organisms living in these environments.In order to cope with these stresses,organisms have evolved specific strategies to adapt to hypoxia,including changes in physiology,gene expression regulation,and genetic mutations.Here,we review how mammals have adapted to the three high-altitude plateaus of the world,the limited oxygen dissolved in deep water habitats,and underground tunnels,with the aim of better understanding the adaptation of mammals to hypoxia.
基金Supported by National Natural Science Foundation of China(Grant No.11271162)the Scientific Research Fund of Heilongjiang Provincial Education Department(Grant No.12531720)the Scientific Research Fund of Mudanjiang Normal University(Grant No.GY201305)
文摘Let M be the multilinear maximal function and = （b1, . . . , bm） be a collection of locally integrable functions. Denote by M and [,M] the maximal commutator and the commutator of M with , respectively. In this paper, the multiple weighted strong and weak type estimates for operators M and [,M] are studied. Some characterizations of the class of functions bj are given, for which these operators satisfy some strong or weak type estimates.
基金supported by China Postdoctoral Science Foundation funded project(2019M662971)The Basic Scientific Research Operating Expenses of Higher Education Institutions of Heilongjiang Province(No.2020-KYYWF-0283).
文摘Short-chain fatty acids are important nutrients that regulate milk fat synthesis.They regulate milk syn-thesis via the sterol regulatory element binding protein 1(SREBP1)pathway;however,the details are still unknown.Here,the regulation and mechanism of sodium acetate(SA)in milk fat synthesis in bovine mammary epithelial cells(BMECs)were assessed.BMECs were treated with SA supplementation(SAþ)or without SA supplementation(SA-),and milk fat synthesis and activation of the SREBP1 pathway were increased(P=0.0045;P=0.0042)by SAþand decreased(P=0.0068;P=0.0031)by SA-,respectively.Overexpression or inhibition of SREBP1 demonstrated that SA promoted milk fat synthesis(P=0.0045)via the SREBP1 pathway.Overexpression or inhibition of TATA element modulatory factor 1(TMF1)demon-strated that TMF1 suppressed activation of the SREBP1 pathway(P=0.0001)and milk fat synthesis(P=0.0022)activated by SAþ.Overexpression or inhibition of TMF1 and SREBP1 showed that TMF1 suppressed milk fat synthesis(P=0.0073)through the SREBP1 pathway.Coimmunoprecipitation analysis revealed that TMF1 interacted with SREBP1 in the cytoplasm and suppressed the nuclear localization of SREBP1(P=0.0066).The absence or presence of SA demonstrated that SA inhibited the expression of TMF1(P=0.0002)and the interaction between TMF1 and SREBP1(P=0.0001).Collectively,our research sug-gested that TMF1 was a new negative regulator of milk fat synthesis.In BMECs,SA promoted the SREBP1 pathway and milk fat synthesis by suppressing TMF1.This study enhances the current understanding of the regulation of milk fat synthesis and provides new scientific data for the regulation of milk fat synthesis.
基金supported by the National Key Research and Development Program of China(Grant No.2019YFA0708502)。
文摘The high-pressure behavior of deep carbonate dictates the state and dynamics of oxidized carbon in the Earth's mantle,playing a vital role in the global carbon cycle and potentially influencing long-term climate change.Optical absorption and Raman spectroscopic measurements were carried out on two natural carbonate samples in diamond-anvil cells up to 60 GPa.Mg-substitution in high-spin siderite FeCO_(3)increases the crystal field absorption band position by approximately 1000 cm^(-1),but such an effect is marginal at>40 GPa when entering the low-spin state.The crystal field absorption band of dolomite cannot be recognized upon compression to 45.8 GPa at room temperature but,in contrast,the high-pressure polymorph of dolomite exhibits a strong absorption band at frequencies higher than(Mg,Fe)CO_(3)in the lowspin state by 2000–2500 cm^(-1).Additionally,these carbonate minerals show more complicated features for the absorption edge,decreasing with pressure and undergoing a dramatic change through the spin crossover.The optical and vibrational properties of carbonate minerals are highly correlated with iron content and spin transition,indicating that iron is preferentially partitioned into low-spin carbonates.These results shed new light on how carbonate minerals evolve in the mantle,which is crucial to decode the deep carbon cycle.
基金Acknowledgements This study was jointly funded by Fundamental Research Funds for Central Universities （2013XK09）, the National Natural Science Foundation of China （Grant No. 61075061）, the Excellent Young Scholars of Higher University of Heilongjiang Province （1252G063）, the Natural Science Foundation of Jiangsu Province （BK2012566）, the Specialized Research Fund for the Doctoral Program of Higher Education （20100095110006）, the Excellent Creative Team Foundation of China University of Mining and Technology （2011ZCX002）, and the Key Advanced Research Program of Mudanjiang Normal University （SY201216）.
文摘The aim of software testing is to find faults in a program under test, so generating test data that can expose the faults of a program is very important. To date, current stud- ies on generating test data for path coverage do not perform well in detecting low probability faults on the covered path. The automatic generation of test data for both path coverage and fault detection using genetic algorithms is the focus of this study. To this end, the problem is first formulated as a bi-objective optimization problem with one constraint whose objectives are the number of faults detected in the traversed path and the risk level of these faults, and whose constraint is that the traversed path must be the target path. An evolution- ary algorithm is employed to solve the formulated model, and several types of fault detection methods are given. Finally, the proposed method is applied to several real-world programs, and compared with a random method and evolutionary opti- mization method in the following three aspects： the number of generations and the time consumption needed to generate desired test data, and the success rate of detecting faults. The experimental results confirm that the proposed method can effectively generate test data that not only traverse the target path but also detect faults lying in it.
基金This study was jointly funded by the Excellent Young Scholars of Higher University of Heilongjiang Province （1252G063）, the National Natural Science Foundation of China （Grant No. 61375067）, the National Basic Research Program of China （2014CB046306-2） the Nat- ural Science Foundation of Jiangsu Province （BK2012566）, the Scientific and Technological Plan Project of Mudanjiang City （Z2013s043）, and the Research Project of Mudanjiang Normal University （SY201216 and QY201214）.
文摘Generating test data that can expose the faults of the program is an important issue in software testing. Al- though previous methods of covering path can generate test data to traverse target path, the test data generated by these methods are difficult in detecting some low-probabilistic faults that lie on the covered paths. We present a method of generating test data for covering multiple paths to detect faults in this study. First, we transform the problem of cover- ing multiple paths and detecting faults into a multi-objective optimization problem with constraint, and construct a mathe- matical model for it. Then, we give a strategy of solving the model based on a weighted genetic algorithm. Finally, we ap- ply our method to several real-world programs, and compare it with several methods. The experimental results confirm that the proposed method can more efficiently generate test data that not only traverse the target paths but also detect faults lying in them than other methods.
基金financially supported by the National Natural Science Foundation of China(no.51672120)the Scientific Research Project of Mudanjiang Normal University(no.1355JG014)+1 种基金the Natural Science Foundation of Hebei Province of China(no.B2020501003)the Fundamental Research Funds for the Central Universities(no.N2023030)。
文摘Mn-based oxides have been regarded as a promising family of cathode materials for high-performance lithium-ion batteries,but the practical applications have been limited because of severe capacity deterioration(such as Li Mn O_(2)and Li Mn_(2)O_(4))as well as further complications from successive structure changes during cycling,low initial coulombic efficiency(such as Li-rich cathode)and oxidization of organic carbonate solvents at high charge potential(such as Li Ni0.5 Mn1.5 O4).Large amounts of efforts have been concentrated on resolving these issues towards practical applications,and many vital progresses have been carried out.Hence,the primary target of this review is focused on different proposed strategies and breakthroughs to enhance the rate performance and cycling stability of nanostructured Mn-based oxide cathode materials for Li-ion batteries,including morphology control,ion doping,surface coatings,composite construction.The combination of delicate architectures with conductive species represents the perspective ways to enhance the conductivity of the cathode materials and further buffer the structure transformation and strain during cycling.At last,based on the elaborated progress,several perspectives of Mn-based oxide cathodes are summarized,and some possible attractive strategies and future development directions of Mn-based oxide cathodes with enhanced electrochemical properties are proposed.The review will offer a detailed introduction of various strategies enhancing electrochemical performance and give a novel viewpoint to shed light on the future innovation in Mn-based oxide cathode materials,which benefits the design and construction of high-performance Mn-based oxide cathode materials in the future.
基金Supported by the National Natural Science Foundation of China(Grant No.11571160)the Research Funds for the Educational Committee of Heilongjiang(Grant No.2019-KYYWF-0909)the Reform and Development Foundation for Local Colleges and Universities of the Central Government(Grant No.2020YQ07)。
文摘Let 6=(bi,b2,...,bm)be a collection of locally integrable functions and T,the com-mutator of multilinear singular integral operator T.Denote by L(δ)and L(δ(·))the Lipschitz spaces and the variable Lipschitz spaces,respectively.The main purpose of this paper is to establish some new characterizations of the(variable)Lipschitz spaces in terms of the boundedness of multilinear commutator T∑b in the context of the variable exponent Lebesgue spaces,that is,the authors give the necessary and sufficient conditions for bj(j=1,2,...,m)to be L(δ)or L(δ(·))via the boundedness of multilinear commutator from products of variable exponent Lebesgue spaces to variable exponent Lebesgue spaces.The authors do so by applying the Fourier series technique and some pointwise esti-mate for the commutators.The key tool in obtaining such pointwise estimate is a certain generalization of the classical sharp maximal operator.
基金Supported by the National Natural Science Foundation of China(No.51072047)
文摘Based on the adsorption of copper ions on single-walled carbon nanotubes（SWNTs） in electrolyte, Cu/SWNTs nanocomposite film was initially prepared on indium-doped tin oxide（ITO） substrate by one-step electrodeposition. This method may provide a versatile and facile pathway to fabricate other SWNTs-supported metal composite films. Electrochemical experiments revealed that the obtained Cu/SWNTs/ITO electrode offered an excellent electrocatalytic activity towards the oxidation of glucose and could be applied to the construction of non-enzymatic glucose biosensor. The linear range of the sensor was 1.0×10–6 to 6.0×10–4 mol/L and the response time was within 2 s. Particularly, its sensitivity reached as high as 1434.67 μA？L？mmol–1？cm–2, which was superior to any other non-enzymatic glucose biosensor based on copper-carbon nanotubes electrode reported previously.
文摘Diamond-like carbon (DLC) films were prepared by PLD process using 308 nm(XeCl) laser beam with high power (500 W) and high frequency(300 Hz). The effects of nitrogen pressure on the structure and properties of the DLC films under such extremely high power and repetition rate were studied. The results indicate that the microstructures of the films are varied from amorphous carbon to graphitized carbon in long-order with the increase of N2 pressure, and the optical properties of the films are deteriorated as compared to that of DLC films without nitrogen.
基金financially supported by the Postdoctoral Science Research Developmental Foundation of Heilongjiang Province (No. LBH-Q12004)the Education Department Foundation from Heilongjiang Province (No.11521575)the Science and Technology Project of Mudanjiang, Heilongjiang Province, China (No.G2012g0008)
文摘Compound ceramic coatings with the main crystalline of Al_2TiO_5（in the as-prepared coating without treatment） were prepared in situ on the surface Ti-6Al-4V alloy by means of pulsed bipolar micro-arc oxidation in Na AlO_2 solution. For the purpose of studying the antioxidation properties of the samples, the coated samples treated in argon and the as-coated samples were calcined in air at 1000 °C. And the related characteristics were investigated by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and X-ray fluorescence（XRF） spectroscopy, respectively. The results show that, when it was calcined in air for 1 h, Al_2TiO_5in the as-prepared coating decomposed and transformed into α-Al_2O_3 and rutile TiO_2.However, after almost 4 h in argon, Al_2TiO_5in the asprepared coating decomposed and the final coating surface contents are completely α-Al_2O_3, and those of the middle interface are mainly Al_2O_3 and Ti_2O_3. The morphologies of the coatings after calcination in argon and air are different.High-temperature oxidation occurred violently in the alloy substrate without coatings. Furthermore, the weight gain curves of the as-prepared samples and the coated samples treated in argon both show a parabolic shape.
基金This work was jointly funded by the Research Projects of Basic Scientific Research Business Expenses in Institutions of Higher Learning of Heilongjiang Province(1353ZD003 and 2018-KYYWFMY-0104)Science and Technology Research Project of Mudanjiang Normal University(YB2019003)+1 种基金the Scientific and Technological Plan Project of Mudanjiang City(Z2018g023)the Innovation Foundation of Science and Technology of Dalian(2018J12GX045).
文摘1 Introduction Regression testing refers to retest code after modification to ensure that changes will not introduce new faults or cause faults in other lines of code[1].Regression test selection(RTS)is one of the predominant techniques.It identifies test cases that are relevant to test recent changes in an application and seeks to reduce the number of test suite while preserving the capability to reveal faults[2].
基金Supported by the National Natural Science Foundation of China (Grant No. 50673051) Beijing Municipal Commission of Edueation
文摘Density functional theory (DFT) calculations were carried out to investigate the organic field effect transistor (OFET) performance of the symmetrical metal-free tetrakis (1,2,5-thiadiazole) porphyrazine (S4)PzH2 and tetrakis (1,4-diamyloxybenzene) (A4)PzH2 as well as the low-symmetry metal-free porphy- razine with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene groups in the ratio 2:2 (cis) and 1:3, that is, (cis-S2A2)PzH2 and (SA3)PzH2, (S = 1,2,5-thiadiazole ring, A = annulated 1,4-diamyloxy-benzene ring, Pz = porphyrazine) in terms of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy, ionization energy (IE), electron affinity (EA), and their reorganization energy (λ) during the charge-transport process. On the basis of Marcus electron transfer theory, electronic couplings (V) and field effect transistor (FET) properties for the four compounds with known crystal structure have been calculated. The electron transfer mobility (μ -) is revealed to be 0.056 cm2·V-1·s-1 for (S4)PzH2. The hole transfer mobility (μ+) is 0.075, 0.098, and 8.20 cm2·V-1·s-1 for (cis-S2A2)PzH2, (SA3)PzH2, and (A4)PzH2, respectively. The present work represents the theoretical effort towards understanding the OFET properties of symmetrical and unsymmetrical porphyrazine derivatives with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene.
基金This work was supported in part by the Heilongjiang Provincial Natural Science Foundation of China under Grant F2018002the Research Funds for the Central Universities under Grants 2572016BB11 and 2572016BB12the Foundation of Heilongjiang Education Department under Grant 1354MSYYB003.
文摘The stereo matching method based on a space-aware network is proposed, which divides the network into threesections: Basic layer, scale layer, and decision layer. This division is beneficial to integrate residue network and densenetwork into the space-aware network model. The vertical splitting method for computing matching cost by usingthe space-aware network is proposed for solving the limitation of GPU RAM. Moreover, a hybrid loss is broughtforward to boost the performance of the proposed deep network. In the proposed stereo matching method, thespace-aware network is used to calculate the matching cost and then cross-based cost aggregation and semi-globalmatching are employed to compute a disparity map. Finally, a disparity-post processing method is utilized suchas subpixel interpolation, median filter, and bilateral filter. The experimental results show this method has a goodperformance on running time and accuracy, with a percentage of erroneous pixels of 1.23% on KITTI 2012 and1.94% on KITTI 2015.
基金supported by the Foundation of Mudanjiang Normal University“Research and Practice on the Construction of Software Engineering Professional Course Group for Engineering Education Certification”(Grant NO.21-XJ21042),“Quality Course Construction for Graduate Course:Information Retrieval and Thesis Writing”(Grant NO.JPKC-2022011)Research Foundation of Education Department of Heilongjiang“Exploration and Practice of New Engineering Talents Training Mode for Computer Majors for Free Trade College”(Grant NO.SJGY 20200732).
文摘To solve the teaching difficulties,including hard cultivating engineering thinking,a reasonable transition of professional training,and deep cooperation of students,which impeded the cultivation effectiveness of students’ability to solve complex engineering problems,the paper proposed a Zongheng group teaching model of curriculum cluster based on projects.Firstly,from the perspective of Metaverse,and considering the professional,current teaching situation and learning situation,we analyzed the professional background and proposed the Zongheng group teaching model of curriculum cluster.Then,the connotation,teaching construction and implementation details are explained.After that,we summarized the teaching effect about the 2 years of exploration and practice in the major of software engineering at College of Computer and Information Technology in Mudanjiang Normal University,to clarify the effect of teaching reform.2 years of teaching practice shows that making full use of the advantages of curriculum cluster,Zongheng group and the project-based teaching method,the long-range training,in-depth student cooperation,and the students’ability of solving complex engineering problems are improved.
文摘In this paper, we conduct research on the development of Daur ethnic education under the influence of big data. Life in the river valley of Daur ethnic which is a nationality has a long history, splendid culture and the national spirit of national self-confidence, the foundation of national culture has a strong self-confidence. Combining the concept of big data and data analysis technique to the Daur ethnic education will largely enhance the result of the current education pattern. The survey of the research indicated that we should pay attention to the precious data captured.
