Gastroparesis refers to abnormal gastric motility characterized by delayed gastric emptying in the absence of mechanical obstruction. The most common etiologies include diabetes, post-surgical and idiopathic. The most...Gastroparesis refers to abnormal gastric motility characterized by delayed gastric emptying in the absence of mechanical obstruction. The most common etiologies include diabetes, post-surgical and idiopathic. The most common symptoms are nausea, vomiting and epigastric pain. Gastroparesis is estimated to affect 4% of the population and symptomatology may range from little effect on daily activity to severe disability and frequent hospitalizations. The gold standard of diagnosis is solid meal gastric scintigraphy. Treatment is multimodal and includes dietary modification, prokinetic and anti-emetic medications, and surgical interventions. New advances in drug therapy, and gastric electrical stimulation techniques have been introduced and might provide new hope to patients with refractory gastroparesis. In this comprehensive review, we discuss gastroparesis with emphasis on the latest developments; from the perspective of the practicing clinician.展开更多
Borehole-to-surface electrical imaging (BSEI) uses a line source and a point source to generate a stable electric field in the ground. In order to study the surface potential of anomalies, three-dimensional forward ...Borehole-to-surface electrical imaging (BSEI) uses a line source and a point source to generate a stable electric field in the ground. In order to study the surface potential of anomalies, three-dimensional forward modeling of point and line sources was conducted by using the finite-difference method and the incomplete Cholesky conjugate gradient (ICCG) method. Then, the damping least square method was used in the 3D inversion of the formation resistivity data. Several geological models were considered in the forward modeling and inversion. The forward modeling results suggest that the potentials generated by the two sources have different surface signatures. The inversion data suggest that the low- resistivity anomaly is outlined better than the high-resistivity anomaly. Moreover, when the point source is under the anomaly, the resistivity anomaly boundaries are better outlined than when using a line source.展开更多
Induced polarization (IP) 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spa...Induced polarization (IP) 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spatial resolution and large probing depth. We discuss data acquisition and 3D IP imaging procedures using the central gradient array with variable electrode distances. A 3D geoelectric model was constructed and then numerically modeled. The data modeling results suggest that this method can capture the features of real geoelectric models. The method was applied to a polymetallic mine in Gansu Province. The results suggest that IP 3D tomography captures the distribution of resistivity and polarization of subsurface media, delineating the extension of abrupt interfaces, and identifies mineralization.展开更多
According to the design method of laser resonator cavity, we optimized the primary parameters of resonator and utilized LD arrays symmetrically pumping manner to implementing output of the high-brightness laser in our...According to the design method of laser resonator cavity, we optimized the primary parameters of resonator and utilized LD arrays symmetrically pumping manner to implementing output of the high-brightness laser in our laser cutter, then which was applied to precisely cutting the conductive film of CulnSe2 solar cells, the buried contact silicon solar cells' electrode groove, and perforating in wafer which is used to the emitter wrap through silicon solar cells. Laser processing precision was less than 40μm, the results have met solar cell's fabrication technology, and made fmally the buried cells' conversion efficiency be improved from 18% to 21%.展开更多
The preparation of calcium phosphate (CP) coating on alumina ceramics using electric pulse stimulating methoe has been investigated. The cup-shaped alumina ceramics were soaked in a simulated body fluid (SBF), and...The preparation of calcium phosphate (CP) coating on alumina ceramics using electric pulse stimulating methoe has been investigated. The cup-shaped alumina ceramics were soaked in a simulated body fluid (SBF), and a square pulse potential with frequency of 1 Hz and voltage of 110 V was applied between the inner and outer surfaces of the alumina cup. Surface morphology of CP coatings during different deposition periods was observed by a Philips XL-30 scanning electron microscope (SEM). Compositional analysis was examined by EDAX. The mechanism of nucleation and growth of CP coating was discussed. SEM result indicates that the coating comprises of a large number of tiny needle-like grains and has a porous microstructure. There is a strong bond between the deposited layer and Al2O3 substrate, which may be due to the gentle growth of the biomimetic method. The EDAX analysis indicates that main composition of the coating is calcium and phosphor. The formation of CP coating may be contributed to the stimulation of electric pulse and the high ions concentration which is 1.5 times of the concentration of SBF solution (1.5SBF solution). Such surface functionalization method by electric pulse potential can be used to prepare CP coating on various electric-insulating bioinert materials for improving their bioactive character.展开更多
A compound coating of electrically conductive and visible transparent film and laser protective film has been developed,this coating has light densities of no less than 4 against 0.53 μm and no less than 3 against 1....A compound coating of electrically conductive and visible transparent film and laser protective film has been developed,this coating has light densities of no less than 4 against 0.53 μm and no less than 3 against 1.06 μm in the range of ±30° angular field.The average transmittance value as high as 60% from 0.4 μm to 0.7 μm has been achieved.The structures of the laser protective filters are compared.The refractive index of a compound material used in the matching layer has been given.Measured results of the laser protective film coating are compared with that of the compound coating.展开更多
By means of improved ligand-field theory, the "pure electronic" pressure-induced shifts (PS's) and the PS's due to electron-phonon interaction (EPI) of R1 line and R2 line of YAG:Cr^3+ have been calculated, ...By means of improved ligand-field theory, the "pure electronic" pressure-induced shifts (PS's) and the PS's due to electron-phonon interaction (EPI) of R1 line and R2 line of YAG:Cr^3+ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. It is demonstrated that the admixture of │t^2 2(^3T1)e^4T2〉 and │t^3 2 ^2E〉 bases in the wavefunction of RI level of YAG:Crs+ and its change with pressure play a key role for the PS of RI line. The behaviors of the "pure electronic" PS of RI line and the PS of RI line due to EPI are different. It is the combined eEect of them that gives rise to the total PS of R1 line, which has satisfactorily explained the experimental results. The systematic analyses and comparisons between the feature of R1-line PS of YAG:Cr^3+ and the ones of three laser crystals (GSGG:Cr^3+, GGG:Cr^3+ and ruby) have been made, and the origin of the difference between them has been revealed.展开更多
Nowadays, electronic devices are more and more integrated into everyday life. These seamless integrations focus on mobility, but at the same time strive to be unobtrusive to the end user. With the introduction of pers...Nowadays, electronic devices are more and more integrated into everyday life. These seamless integrations focus on mobility, but at the same time strive to be unobtrusive to the end user. With the introduction of personal data assistants and intelligent cellular phones for the searching of the website, true mobile computing is closer than ever. However, battery technology, which powers most of these mobile connectivity solutions, has not kept up the same pace of improvement. The paper describes a methodology for the design and performance of a self-excited permanent-magnet generator applied to low power supplies. It combines an analytical field model, a lumped reluctance equivalent magnetic circuit, and an equivalent electrical circuit. An illustrated example of a 15-mW, 290-r/min generator is given, and the analysis techniques are validated by measurements on a prototype system.展开更多
Developing transition metal-based electrocatalysts with rich active sites for water electrolysis plays important roles in renewable energy fields. So far, some strategies including designing nanostructures, incorporat...Developing transition metal-based electrocatalysts with rich active sites for water electrolysis plays important roles in renewable energy fields. So far, some strategies including designing nanostructures, incorporating conductive support or foreign elements have been adopted to develop efficient electrocat- alysts. Herein, we summarize recent progresses and propose in-situ electrochemical activation as a new pretreating technique for enhanced catalytic performances. The activation techniques mainly comprise facile electrochemical processes such as anodic oxidation, cathodic reduction, etching, lithium-assisted tuning and counter electrode electro-dissolution. During these electrochemicaI treatments, the catalyst surfaces are modified from bulk phase, which can tune local electronic structures, create more active spe- cies. enlarge surface area and thus improve the catalytic performances. Meanwhile, this technique can couple the atomic, electronic structures with electrocatalysis mechanisms for water splitting. Compared to traditional chemical treatment, the in-situ electrochemical activation techniques have superior advantages such as facile operation, mild environment, variable control, high efficiency and flex- ibility. This review may provide guidance for improving water electrolysis efficiencies and hold promis- ing for application in many other energy-conversion fields such as supercapacitors, fuel cells and batteries.展开更多
The rapid development of portable and wearable electronic devices has increased demand for flexible and efficient energy harvesting and storage units. Conventionally, these are built and used separately as discrete co...The rapid development of portable and wearable electronic devices has increased demand for flexible and efficient energy harvesting and storage units. Conventionally, these are built and used separately as discrete components. Herein, we propose a simple and cost-effective laser engraving technique for fabricating a flexible self-charging micro-supercapacitor power unit (SCMPU), by integrating a triboelectric nanogenerator (TENG) and a micro-supercapacitor (MSC) array into a single device. The SCMPU can be charged directly by ambient mechanical motion. We demonstrate the ability of the SCMPU to continuously power light-emitting diodes and a commercial hygrothermograph. This inves- tigation may promote the development of sustainable self-powered systems and provide a promising new research application for supercapacitors.展开更多
Objective There is substantial evidence supporting the notion that the anterior cingulate cortex (ACC) is an important limbic structure involved in multiple brain functions such as sensory perception, motor conflict...Objective There is substantial evidence supporting the notion that the anterior cingulate cortex (ACC) is an important limbic structure involved in multiple brain functions such as sensory perception, motor conflict monitoring, memory, emotion and cognition. It has been shown that long term potentiation (LTP) is an important synaptic model of neural plasticity in the ACC, however, little is known about the spatiotemporal properties of ACC at network level. The present study was designed to see the LTP induction effects across different layers of the ACC by using different conditioning stimuli (CS) protocols. Methods A unique multi-electrode array recording technique was used in the acutely-dissociated ACC slices of rats. Long and short train theta burst stimulation (TBS) paradigms were applied in layer V-VI as the CS and the LTP induction effects were compared across different layers of the ACC. Briefly, both long and short train TBS are composed of bursts (4 pulses at 100 Hz) with a 200 ms interval, however, the former (TBS1) was with 10 trains and the latter (TBS2) was with 5 trains. After test stimulation at layer V-VI in the ACC, network field potentials (FPs) could be simultaneously recorded across all layers of the ACC. Results The waveforms of FPs were different across different layers. Namely, positive-going waveforms were recorded in layer I and negative-going waveforms were recorded in layers V-VI, in contrast, complex waveforms were localized mainly in layers II-III. Following application of two CS protocols, the induction rate of LTP was significantly different between TBS 1 and TBS2 regardless of the spatial properties. TBS1 had more than 60% success, while TBS2 was less than 25% in induction of LTP. Moreover, both the 2 CS protocols could induce LTP in layers II-III and layers V-VI without layer-related difference. However, no LTP was inducible in layer I. Conclusion The present findings indicate that stimulation protocols may, at least in part, account for a large portion of variations among previous LTP studies, and hence highlight the importance of selecting the best LTP induction protocol when designing such experiments. Moreover, the present results demonstrate the prominent superiority of multi-electrode array recording in revealing the network properties of synaptic activities in the ACC, especially in comparing the spatiotemporal characteristics between different layers of this structure.展开更多
文摘Gastroparesis refers to abnormal gastric motility characterized by delayed gastric emptying in the absence of mechanical obstruction. The most common etiologies include diabetes, post-surgical and idiopathic. The most common symptoms are nausea, vomiting and epigastric pain. Gastroparesis is estimated to affect 4% of the population and symptomatology may range from little effect on daily activity to severe disability and frequent hospitalizations. The gold standard of diagnosis is solid meal gastric scintigraphy. Treatment is multimodal and includes dietary modification, prokinetic and anti-emetic medications, and surgical interventions. New advances in drug therapy, and gastric electrical stimulation techniques have been introduced and might provide new hope to patients with refractory gastroparesis. In this comprehensive review, we discuss gastroparesis with emphasis on the latest developments; from the perspective of the practicing clinician.
基金sponsored by the National Major Project(No.2016ZX05014-001)the National Natural Science Foundation of China(No.41172130 and U1403191)the Fundamental Research Funds for the Central Universities(No.2-9-2015-209)
文摘Borehole-to-surface electrical imaging (BSEI) uses a line source and a point source to generate a stable electric field in the ground. In order to study the surface potential of anomalies, three-dimensional forward modeling of point and line sources was conducted by using the finite-difference method and the incomplete Cholesky conjugate gradient (ICCG) method. Then, the damping least square method was used in the 3D inversion of the formation resistivity data. Several geological models were considered in the forward modeling and inversion. The forward modeling results suggest that the potentials generated by the two sources have different surface signatures. The inversion data suggest that the low- resistivity anomaly is outlined better than the high-resistivity anomaly. Moreover, when the point source is under the anomaly, the resistivity anomaly boundaries are better outlined than when using a line source.
基金funded jointly by the National High Technology Research and Development Program(863 Program:No.2014AA06A610)special funds for basic scientific research business expenses of the Chinese Academy of Geological Sciences(No.YYWF201632)the National Major Scientific Instruments and Equipment Development Projects(No.2011YQ050060)
文摘Induced polarization (IP) 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spatial resolution and large probing depth. We discuss data acquisition and 3D IP imaging procedures using the central gradient array with variable electrode distances. A 3D geoelectric model was constructed and then numerically modeled. The data modeling results suggest that this method can capture the features of real geoelectric models. The method was applied to a polymetallic mine in Gansu Province. The results suggest that IP 3D tomography captures the distribution of resistivity and polarization of subsurface media, delineating the extension of abrupt interfaces, and identifies mineralization.
基金This work was supported by the Student’s Innovating Foundationin Nankai University.
文摘According to the design method of laser resonator cavity, we optimized the primary parameters of resonator and utilized LD arrays symmetrically pumping manner to implementing output of the high-brightness laser in our laser cutter, then which was applied to precisely cutting the conductive film of CulnSe2 solar cells, the buried contact silicon solar cells' electrode groove, and perforating in wafer which is used to the emitter wrap through silicon solar cells. Laser processing precision was less than 40μm, the results have met solar cell's fabrication technology, and made fmally the buried cells' conversion efficiency be improved from 18% to 21%.
文摘The preparation of calcium phosphate (CP) coating on alumina ceramics using electric pulse stimulating methoe has been investigated. The cup-shaped alumina ceramics were soaked in a simulated body fluid (SBF), and a square pulse potential with frequency of 1 Hz and voltage of 110 V was applied between the inner and outer surfaces of the alumina cup. Surface morphology of CP coatings during different deposition periods was observed by a Philips XL-30 scanning electron microscope (SEM). Compositional analysis was examined by EDAX. The mechanism of nucleation and growth of CP coating was discussed. SEM result indicates that the coating comprises of a large number of tiny needle-like grains and has a porous microstructure. There is a strong bond between the deposited layer and Al2O3 substrate, which may be due to the gentle growth of the biomimetic method. The EDAX analysis indicates that main composition of the coating is calcium and phosphor. The formation of CP coating may be contributed to the stimulation of electric pulse and the high ions concentration which is 1.5 times of the concentration of SBF solution (1.5SBF solution). Such surface functionalization method by electric pulse potential can be used to prepare CP coating on various electric-insulating bioinert materials for improving their bioactive character.
文摘A compound coating of electrically conductive and visible transparent film and laser protective film has been developed,this coating has light densities of no less than 4 against 0.53 μm and no less than 3 against 1.06 μm in the range of ±30° angular field.The average transmittance value as high as 60% from 0.4 μm to 0.7 μm has been achieved.The structures of the laser protective filters are compared.The refractive index of a compound material used in the matching layer has been given.Measured results of the laser protective film coating are compared with that of the compound coating.
文摘By means of improved ligand-field theory, the "pure electronic" pressure-induced shifts (PS's) and the PS's due to electron-phonon interaction (EPI) of R1 line and R2 line of YAG:Cr^3+ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. It is demonstrated that the admixture of │t^2 2(^3T1)e^4T2〉 and │t^3 2 ^2E〉 bases in the wavefunction of RI level of YAG:Crs+ and its change with pressure play a key role for the PS of RI line. The behaviors of the "pure electronic" PS of RI line and the PS of RI line due to EPI are different. It is the combined eEect of them that gives rise to the total PS of R1 line, which has satisfactorily explained the experimental results. The systematic analyses and comparisons between the feature of R1-line PS of YAG:Cr^3+ and the ones of three laser crystals (GSGG:Cr^3+, GGG:Cr^3+ and ruby) have been made, and the origin of the difference between them has been revealed.
文摘Nowadays, electronic devices are more and more integrated into everyday life. These seamless integrations focus on mobility, but at the same time strive to be unobtrusive to the end user. With the introduction of personal data assistants and intelligent cellular phones for the searching of the website, true mobile computing is closer than ever. However, battery technology, which powers most of these mobile connectivity solutions, has not kept up the same pace of improvement. The paper describes a methodology for the design and performance of a self-excited permanent-magnet generator applied to low power supplies. It combines an analytical field model, a lumped reluctance equivalent magnetic circuit, and an equivalent electrical circuit. An illustrated example of a 15-mW, 290-r/min generator is given, and the analysis techniques are validated by measurements on a prototype system.
基金financially supported by Shandong Provincial Natural Science Foundation,China (ZR2017MB059)the National Natural Science Foundation of China (21776314)the Fundamental Research Funds for the Central Universities (18CX05016A)
文摘Developing transition metal-based electrocatalysts with rich active sites for water electrolysis plays important roles in renewable energy fields. So far, some strategies including designing nanostructures, incorporating conductive support or foreign elements have been adopted to develop efficient electrocat- alysts. Herein, we summarize recent progresses and propose in-situ electrochemical activation as a new pretreating technique for enhanced catalytic performances. The activation techniques mainly comprise facile electrochemical processes such as anodic oxidation, cathodic reduction, etching, lithium-assisted tuning and counter electrode electro-dissolution. During these electrochemicaI treatments, the catalyst surfaces are modified from bulk phase, which can tune local electronic structures, create more active spe- cies. enlarge surface area and thus improve the catalytic performances. Meanwhile, this technique can couple the atomic, electronic structures with electrocatalysis mechanisms for water splitting. Compared to traditional chemical treatment, the in-situ electrochemical activation techniques have superior advantages such as facile operation, mild environment, variable control, high efficiency and flex- ibility. This review may provide guidance for improving water electrolysis efficiencies and hold promis- ing for application in many other energy-conversion fields such as supercapacitors, fuel cells and batteries.
文摘The rapid development of portable and wearable electronic devices has increased demand for flexible and efficient energy harvesting and storage units. Conventionally, these are built and used separately as discrete components. Herein, we propose a simple and cost-effective laser engraving technique for fabricating a flexible self-charging micro-supercapacitor power unit (SCMPU), by integrating a triboelectric nanogenerator (TENG) and a micro-supercapacitor (MSC) array into a single device. The SCMPU can be charged directly by ambient mechanical motion. We demonstrate the ability of the SCMPU to continuously power light-emitting diodes and a commercial hygrothermograph. This inves- tigation may promote the development of sustainable self-powered systems and provide a promising new research application for supercapacitors.
基金supported by the National Basic Research (973) Program of China (No.2006CB500800)the National Natural Science Foundation of China (No. 30670692 and 30770668)
文摘Objective There is substantial evidence supporting the notion that the anterior cingulate cortex (ACC) is an important limbic structure involved in multiple brain functions such as sensory perception, motor conflict monitoring, memory, emotion and cognition. It has been shown that long term potentiation (LTP) is an important synaptic model of neural plasticity in the ACC, however, little is known about the spatiotemporal properties of ACC at network level. The present study was designed to see the LTP induction effects across different layers of the ACC by using different conditioning stimuli (CS) protocols. Methods A unique multi-electrode array recording technique was used in the acutely-dissociated ACC slices of rats. Long and short train theta burst stimulation (TBS) paradigms were applied in layer V-VI as the CS and the LTP induction effects were compared across different layers of the ACC. Briefly, both long and short train TBS are composed of bursts (4 pulses at 100 Hz) with a 200 ms interval, however, the former (TBS1) was with 10 trains and the latter (TBS2) was with 5 trains. After test stimulation at layer V-VI in the ACC, network field potentials (FPs) could be simultaneously recorded across all layers of the ACC. Results The waveforms of FPs were different across different layers. Namely, positive-going waveforms were recorded in layer I and negative-going waveforms were recorded in layers V-VI, in contrast, complex waveforms were localized mainly in layers II-III. Following application of two CS protocols, the induction rate of LTP was significantly different between TBS 1 and TBS2 regardless of the spatial properties. TBS1 had more than 60% success, while TBS2 was less than 25% in induction of LTP. Moreover, both the 2 CS protocols could induce LTP in layers II-III and layers V-VI without layer-related difference. However, no LTP was inducible in layer I. Conclusion The present findings indicate that stimulation protocols may, at least in part, account for a large portion of variations among previous LTP studies, and hence highlight the importance of selecting the best LTP induction protocol when designing such experiments. Moreover, the present results demonstrate the prominent superiority of multi-electrode array recording in revealing the network properties of synaptic activities in the ACC, especially in comparing the spatiotemporal characteristics between different layers of this structure.