Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S...Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing strategy.Efficient charge transfer from ZnIn_(2)S_(4) to WSe_(2)was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face contact.As a result,the prepared WSe_(2)/ZnIn_(2)S_(4) heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/(g h)was achieved with an apparent quantum yield of 45.7%at 420 nm.The work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.展开更多
Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy de...Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy densities are extremely hindered by the sulfur loss,low Coulombic efficiency,and short cycling life originating from the polysulfide(LiPS)shuttle.In this study,two-dimensional(2D)ZnCo_(2)O_(4) microsheets fabricated by a facile hydrothermal process are employed to modify the separator,for improving the electrochemical performances of Li-S cells.The resulting 2D Zn Co_(2)O_(4)-coated separator features a coating thickness of approximately 10 lm,high ionic conductivity of 1.8 m S/cm,and low mass loading of 0.2 mg/cm^(2).This 2D ZnCo_(2)O_(4)-coated separator effectively inhibits Li PS shuttle by a strong chemical interaction with Li PS as well as promotes the redox kinetics by Zn CO2O4-coated layers,as determined by X-ray photoelectron spectroscopy analysis,self-discharge,time-dependent permeation test,Li symmetric cell test,and Li2S nucleation analyses.Consequently,the Li-S batteries based on the 2D Zn Co_(2)O_(4)-coated separator exhibit a high initial discharge capacity of 1292.2 m Ah/g at 0.1 C.Moreover,they exhibit excellent long cycle stability at 1 and 2 C with capacity retention of 84%and 86%even after800 cycles,corresponding to a capacity fading rate of 0.020%and 0.016%per cycle,respectively.Effectively,these Li-S cells with a high sulfur loading at 5.3 mg/cm^(2) and low electrolyte concentration of 9 l L/mg deliver a high discharge capacity of 4.99 m Ah/cm^(2) after 200 cycles at 0.1 C.展开更多
Starting from the extended tanh-function method （ETM） based on the mapping method, the variable separation solutions of the （2＋1）-dimensional asymmetric Nizhnik Novikov Veselov （ANNV） system are derived. By fur...Starting from the extended tanh-function method （ETM） based on the mapping method, the variable separation solutions of the （2＋1）-dimensional asymmetric Nizhnik Novikov Veselov （ANNV） system are derived. By further study, we find that these variable separation solutions are seemingly independent of but actually dependent on each other. Based on the variable separation solution and by choosing appropriate functions, some novel and interesting interactions between special solitons, such as bell-like compacton, peakon-like compacton and compacton-like semifoldon, are investigated.展开更多
In the last decade, the rise of two-dimensional （2D） materials has attracted a tremendous amount of interest for the entire field of photonics and opto-electronics. The mechanism of light-matter interaction in 2D ma...In the last decade, the rise of two-dimensional （2D） materials has attracted a tremendous amount of interest for the entire field of photonics and opto-electronics. The mechanism of light-matter interaction in 2D materials challenges the knowledge of materials physics, which drives the rapid development of materials synthesis and device applications. 2D materials coupled with plasmonic effects show impressive optical characteristics, involving efficient charge transfer, plas- monic hot electrons doping, enhanced light-emitting, and ultrasensitive photodetection. Here, we briefly review the recent remarkable progress of 2D materials, mainly on graphene and transition metal dichalcogenides, focusing on their tunable optical properties and improved opto-electronic devices with plasmonic effects. The mechanism of plasmon enhanced light-matter interaction in 2D materials is elaborated in detail, and the state-of-the-art of device applications is compre- hensively described. In the future, the field of 2D materials holds great promise as an important platform for materials science and opto-electronic engineering, enabling an emerging interdisciplinary research field spanning from clean energy to information technology.展开更多
A class of new doubly periodic wave solutions for （2＋1）-dimensional KdV equation are obtained by introducing appropriate Jacobi elliptic functions and Weierstrass elliptic functions in the general solution（contain...A class of new doubly periodic wave solutions for （2＋1）-dimensional KdV equation are obtained by introducing appropriate Jacobi elliptic functions and Weierstrass elliptic functions in the general solution（contains two arbitrary functions） got by means of multilinear variable separation approach for （2＋1）-dimensional KdV equation. Limiting cases are considered and some localized excitations are derived, such as dromion, multidromions, dromion-antidromion, multidromions-antidromions, and so on. Some solutions of the dromion-antidromion and multidromions-antidromions are periodic in one direction but localized in the other direction. The interaction properties of these solutions, which are numerically studied, reveal that some of them are nonelastic and some are completely elastic. Furthermore, these results are visualized.展开更多
A new ion-pair complex, [BzMeQ1]2[Ni（nmt）2]1（[BzMeQ1]^＋ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate） has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction ...A new ion-pair complex, [BzMeQ1]2[Ni（nmt）2]1（[BzMeQ1]^＋ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate） has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction methods. Complex 1 is of triclinic, space group PI, with a = 9.079（2）, b = 10.154（2）, c = 11.243（2）A, α= 81.58（1）, β= 69.63（1）, γ = 68.02（1）°, V= 940.1（3）A3, Dc = 1.427 g/cm^3, Z = 1, F（000） = 418 and R = 0.0442. A 2D layer structure is formed via the cation-cation π…π and C-H…π interactions observed in the solid state of the complex.展开更多
To validate the ability of full configuration interaction quantum Monte Carlo （FCIQMC） for studying the 2D Hubbard model near half-filling regime, the ground state energies of a 4×44×4 square lattice syste...To validate the ability of full configuration interaction quantum Monte Carlo （FCIQMC） for studying the 2D Hubbard model near half-filling regime, the ground state energies of a 4×44×4 square lattice system with various interaction strengths are calculated. It is found that the calculated results are in good agreement with those obtained by exact diagonalization （i.e., the exact values for a given basis set） when the population of psi particles （psips） is higher than the critical population required to correctly sample the ground state wave function. In addition, the variations of the average computational time per 20 Monte Carlo cycles with the coupling strength and the number of processors are also analyzed. The calculated results show that the computational efficiency of an FCIQMC calculation is mainly affected by the total population of psips and the communication between processors. These results can provide useful references for understanding the FCIQMC algorithm, studying the ground state properties of the 2D Hubbard model for the larger system size by the FCIQMC method and using a computational budget as effectively as possible.展开更多
Crown peptide is a kind of special conformation found on the homodetic cyclopeptide, regular array about the main chain containing imido groups, and the monolithic conformation presents coronary analogy to crown ether...Crown peptide is a kind of special conformation found on the homodetic cyclopeptide, regular array about the main chain containing imido groups, and the monolithic conformation presents coronary analogy to crown ether. There are high symmetrical ionophores belonging to Cn point group. The channels or apertures can form easily for recognizing certain ion or molecular, and also the function of intending dual-recognition and the ability for transporting as ionophores can be possessed. Under the method of density functional theory, the geometry structures, values energy and population analysis of the combo of crown tetraalanylpeptide （C4-Ala） with NO3- and SO4/2- are calculated, based on the foundation of former studies. Compared with the structure of C4-AIa without NO3- and SO4/2- it is found that the coronary shape changes little in the complex of C4-Ala-YOm/n-, and the electrons transfer between C4-AIa and YOm/n- at the mean time. There are hydrogen bond between oxygen of YOm/n- and the hydrogen from imine groups of C4-AIa, and they become weaker when the average charge density lessens.展开更多
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater...Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.展开更多
The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonse...The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonseparable scaling function are also given. In the numerical experiments, it appears that nonseparable scaling function interpolation has better convergence results than scalar wavelet systems in some cases.展开更多
<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular...<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular dysfunction can’t be detected using 2D echocardiography which </span><span style="font-family:Verdana;">is </span><span style="font-family:;" "=""><span style="font-family:Verdana;">routinely used for cardiac evaluation of diabetic patients. We aimed to determine the prevalence and factors associated to left ventricular global longitudinal strain (LV GLS) impairment in type 2 diabetes Cameroonians patients. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> We conducted a cross-sectional study from January 2019 to June 2019, including type 2 diabetes patients with preserved left ventricle ejection fraction. Clinical and echocardiographic data were collected, and LV GLS was assessed using speckle tracking technique, a value ≤</span></span><span style="font-family:Verdana;"> -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">16% been considered as normal value. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> We recruited 95 patients, with a mean age of 57.4 ± 11.8 years old and median diabetes duration of 5 [2 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 12] years. Echocardiographic evaluation found 56.3% of left ventricle remodelling, 51.6% of left ventricle diastolic dysfunction and mean left ventricle ejection of 63.3</span><span style="font-family:Verdana;">%</span><span style="font-family:Verdana;"> ± 6.6%. LV GLS impairment was present in 43.2% (95% CI: 32.6 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 53.7) of the participants. After adjustment to all significantly associated factors, Obesity (aOR: 4;95% CI: 1.5 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 10.6) and diastolic dysfunction (aOR: 3.1;95% CI: 1.2 </span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> 8.2) were independent factors associated with LV GLS. </span><b><span style="font-family:Verdana;">Conclusions:</span></b><span style="font-family:Verdana;"> Subclinical systolic dysfunction assessed by LV GLS impairment is frequent in diabetic patients. Further research should be carried out more extensively to integrate LV GLS in the type 2 diabetes patients’ routine follow up for a better prognostic outcome, especially in low-incomes countries.</span></span>展开更多
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o...In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.展开更多
基金financially supported by the National Natural Science Foundation of China (No.52106259)the Fundamental Research Funds for the Central Universities (2024MS013)Key Research and Development Program of Shaanxi (Program No.2022LL-JB-08)。
文摘Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing strategy.Efficient charge transfer from ZnIn_(2)S_(4) to WSe_(2)was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face contact.As a result,the prepared WSe_(2)/ZnIn_(2)S_(4) heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/(g h)was achieved with an apparent quantum yield of 45.7%at 420 nm.The work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.
基金supported by a grant from R&D Program of the Korea Railroad Research Institute,Republic of Korea。
文摘Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy densities are extremely hindered by the sulfur loss,low Coulombic efficiency,and short cycling life originating from the polysulfide(LiPS)shuttle.In this study,two-dimensional(2D)ZnCo_(2)O_(4) microsheets fabricated by a facile hydrothermal process are employed to modify the separator,for improving the electrochemical performances of Li-S cells.The resulting 2D Zn Co_(2)O_(4)-coated separator features a coating thickness of approximately 10 lm,high ionic conductivity of 1.8 m S/cm,and low mass loading of 0.2 mg/cm^(2).This 2D ZnCo_(2)O_(4)-coated separator effectively inhibits Li PS shuttle by a strong chemical interaction with Li PS as well as promotes the redox kinetics by Zn CO2O4-coated layers,as determined by X-ray photoelectron spectroscopy analysis,self-discharge,time-dependent permeation test,Li symmetric cell test,and Li2S nucleation analyses.Consequently,the Li-S batteries based on the 2D Zn Co_(2)O_(4)-coated separator exhibit a high initial discharge capacity of 1292.2 m Ah/g at 0.1 C.Moreover,they exhibit excellent long cycle stability at 1 and 2 C with capacity retention of 84%and 86%even after800 cycles,corresponding to a capacity fading rate of 0.020%and 0.016%per cycle,respectively.Effectively,these Li-S cells with a high sulfur loading at 5.3 mg/cm^(2) and low electrolyte concentration of 9 l L/mg deliver a high discharge capacity of 4.99 m Ah/cm^(2) after 200 cycles at 0.1 C.
基金Project supported by the National Natural Science Foundation of China （Grant No 10672147） and Natural Science Foundation of Zhejiang Forestry University, China （Grant No 2006FR035）. Acknowledgments The authors are indebted to Professor Zhang J F for his helpful suggestions and fruitful discussions, and also express their sincere thanks to the editors and the anonymous referees for their constructive suggestions and kind help.
文摘Starting from the extended tanh-function method （ETM） based on the mapping method, the variable separation solutions of the （2＋1）-dimensional asymmetric Nizhnik Novikov Veselov （ANNV） system are derived. By further study, we find that these variable separation solutions are seemingly independent of but actually dependent on each other. Based on the variable separation solution and by choosing appropriate functions, some novel and interesting interactions between special solitons, such as bell-like compacton, peakon-like compacton and compacton-like semifoldon, are investigated.
基金Project supported by the National Basic Research Program of China(Grant No.2015CB932403)the National Natural Science Foundation of China(Grant Nos.61422501,11674012,11374023,and 61521004)+2 种基金Beijing Natural Science Foundation,China(Grant No.L140007)Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No.201420)National Program for Support of Top-notch Young Professionals,China
文摘In the last decade, the rise of two-dimensional （2D） materials has attracted a tremendous amount of interest for the entire field of photonics and opto-electronics. The mechanism of light-matter interaction in 2D materials challenges the knowledge of materials physics, which drives the rapid development of materials synthesis and device applications. 2D materials coupled with plasmonic effects show impressive optical characteristics, involving efficient charge transfer, plas- monic hot electrons doping, enhanced light-emitting, and ultrasensitive photodetection. Here, we briefly review the recent remarkable progress of 2D materials, mainly on graphene and transition metal dichalcogenides, focusing on their tunable optical properties and improved opto-electronic devices with plasmonic effects. The mechanism of plasmon enhanced light-matter interaction in 2D materials is elaborated in detail, and the state-of-the-art of device applications is compre- hensively described. In the future, the field of 2D materials holds great promise as an important platform for materials science and opto-electronic engineering, enabling an emerging interdisciplinary research field spanning from clean energy to information technology.
基金Foundation item： Supported by the National Natural Science Foundation of China（10647112, 10871040） Acknowledgement The authors are in debt to thank the helpful discussions with Prof Qin and Dr A P Deng.
文摘A class of new doubly periodic wave solutions for （2＋1）-dimensional KdV equation are obtained by introducing appropriate Jacobi elliptic functions and Weierstrass elliptic functions in the general solution（contains two arbitrary functions） got by means of multilinear variable separation approach for （2＋1）-dimensional KdV equation. Limiting cases are considered and some localized excitations are derived, such as dromion, multidromions, dromion-antidromion, multidromions-antidromions, and so on. Some solutions of the dromion-antidromion and multidromions-antidromions are periodic in one direction but localized in the other direction. The interaction properties of these solutions, which are numerically studied, reveal that some of them are nonelastic and some are completely elastic. Furthermore, these results are visualized.
基金the President's Science Foundation of South China Agricultural University (No. 2005K092)
文摘A new ion-pair complex, [BzMeQ1]2[Ni（nmt）2]1（[BzMeQ1]^＋ = 1-benzyl-4-ntethylquino- linium, mnta- -- maleonitriledithiolate） has been synthesized and structurally characterized by IR, ESI-MS and X-ray diffraction methods. Complex 1 is of triclinic, space group PI, with a = 9.079（2）, b = 10.154（2）, c = 11.243（2）A, α= 81.58（1）, β= 69.63（1）, γ = 68.02（1）°, V= 940.1（3）A3, Dc = 1.427 g/cm^3, Z = 1, F（000） = 418 and R = 0.0442. A 2D layer structure is formed via the cation-cation π…π and C-H…π interactions observed in the solid state of the complex.
基金Supported by the Natural Science Foundation for Colleges and Universities of Jiangsu Province under Grant No 16KJB140008the National Natural Science Foundation of China under Grant Nos 11447204 and 11647164+1 种基金the Natural Science Foundation of Jiangsu Province under Grant No BK20151079the Scientific Research Foundation of Nanjing Xiaozhuang University under Grant No 2015NXY34
文摘To validate the ability of full configuration interaction quantum Monte Carlo （FCIQMC） for studying the 2D Hubbard model near half-filling regime, the ground state energies of a 4×44×4 square lattice system with various interaction strengths are calculated. It is found that the calculated results are in good agreement with those obtained by exact diagonalization （i.e., the exact values for a given basis set） when the population of psi particles （psips） is higher than the critical population required to correctly sample the ground state wave function. In addition, the variations of the average computational time per 20 Monte Carlo cycles with the coupling strength and the number of processors are also analyzed. The calculated results show that the computational efficiency of an FCIQMC calculation is mainly affected by the total population of psips and the communication between processors. These results can provide useful references for understanding the FCIQMC algorithm, studying the ground state properties of the 2D Hubbard model for the larger system size by the FCIQMC method and using a computational budget as effectively as possible.
文摘Crown peptide is a kind of special conformation found on the homodetic cyclopeptide, regular array about the main chain containing imido groups, and the monolithic conformation presents coronary analogy to crown ether. There are high symmetrical ionophores belonging to Cn point group. The channels or apertures can form easily for recognizing certain ion or molecular, and also the function of intending dual-recognition and the ability for transporting as ionophores can be possessed. Under the method of density functional theory, the geometry structures, values energy and population analysis of the combo of crown tetraalanylpeptide （C4-Ala） with NO3- and SO4/2- are calculated, based on the foundation of former studies. Compared with the structure of C4-AIa without NO3- and SO4/2- it is found that the coronary shape changes little in the complex of C4-Ala-YOm/n-, and the electrons transfer between C4-AIa and YOm/n- at the mean time. There are hydrogen bond between oxygen of YOm/n- and the hydrogen from imine groups of C4-AIa, and they become weaker when the average charge density lessens.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61888102,52272172,and 52102193)the Major Program of the National Natural Science Foundation of China(Grant No.92163206)+2 种基金the National Key Research and Development Program of China(Grant Nos.2021YFA1201501 and 2022YFA1204100)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB30000000)the Fundamental Research Funds for the Central Universities.
文摘Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.
文摘The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonseparable scaling function are also given. In the numerical experiments, it appears that nonseparable scaling function interpolation has better convergence results than scalar wavelet systems in some cases.
文摘<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular dysfunction can’t be detected using 2D echocardiography which </span><span style="font-family:Verdana;">is </span><span style="font-family:;" "=""><span style="font-family:Verdana;">routinely used for cardiac evaluation of diabetic patients. We aimed to determine the prevalence and factors associated to left ventricular global longitudinal strain (LV GLS) impairment in type 2 diabetes Cameroonians patients. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> We conducted a cross-sectional study from January 2019 to June 2019, including type 2 diabetes patients with preserved left ventricle ejection fraction. Clinical and echocardiographic data were collected, and LV GLS was assessed using speckle tracking technique, a value ≤</span></span><span style="font-family:Verdana;"> -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">16% been considered as normal value. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> We recruited 95 patients, with a mean age of 57.4 ± 11.8 years old and median diabetes duration of 5 [2 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 12] years. Echocardiographic evaluation found 56.3% of left ventricle remodelling, 51.6% of left ventricle diastolic dysfunction and mean left ventricle ejection of 63.3</span><span style="font-family:Verdana;">%</span><span style="font-family:Verdana;"> ± 6.6%. LV GLS impairment was present in 43.2% (95% CI: 32.6 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 53.7) of the participants. After adjustment to all significantly associated factors, Obesity (aOR: 4;95% CI: 1.5 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 10.6) and diastolic dysfunction (aOR: 3.1;95% CI: 1.2 </span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> 8.2) were independent factors associated with LV GLS. </span><b><span style="font-family:Verdana;">Conclusions:</span></b><span style="font-family:Verdana;"> Subclinical systolic dysfunction assessed by LV GLS impairment is frequent in diabetic patients. Further research should be carried out more extensively to integrate LV GLS in the type 2 diabetes patients’ routine follow up for a better prognostic outcome, especially in low-incomes countries.</span></span>
基金Project(51104185)supported by the National Natural Science Foundation of ChinaProject(2010QZZD003)supported by the Key Project of Central South University of Fundamental Research Funds for the Central Universities of China
文摘In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.
