Detection of target analytes at low concentrations is significant in various fields,including pharmaceuticals,healthcare,and environmental protection.Theophylline(TP),a natural alkaloid used as a bronchodilator to tre...Detection of target analytes at low concentrations is significant in various fields,including pharmaceuticals,healthcare,and environmental protection.Theophylline(TP),a natural alkaloid used as a bronchodilator to treat respiratory disorders such as asthma,bronchitis,and emphysema,has a narrow therapeutic window with a safe plasma concentration ranging from 55.5-111.0μmol·L^(-1)in adults.Accurate monitoring of TP levels is essential because too low or too high can cause se-rious side effects.In this regard,non-enzymatic electrochemical sensors offer a practical solution with rapidity,portability,and high sensitivity.This article aims to provide a comprehensive review of the recent developments of non-enzymatic electrochemical sensors for TP detection,highlighting the basic principles,electro-oxidation mechanisms,catalytic effects,and the role of modifying materials on electrode performance.Carbon-based electrodes such as glassy carbon electrodes(GCEs),carbon paste electrodes(CPEs),and carbon screen-printed electrodes(SPCEs)have become the primary choices for non-enzymatic sensors due to their chemical stability,low cost,and flexibility in modification.This article identifies the sig-nificant contribution of various modifying materials,including nanomaterials such as carbon nanotubes(CNTs),graphene,metal oxides,and multi-element nanocomposites.These modifications enhance sensors’electron transfer,sensitivity,and selectivity in detecting TP at low concentrations in complex media such as blood plasma and pharmaceutical samples.The electro-oxidation mechanism of TP is also discussed in depth,emphasizing the hydroxyl and carbonyl reaction pathways strongly influenced by pH and electrode materials.These mechanisms guide the selection of the appropriate electrode ma-terial for a particular application.The main contribution of this article is to identify superior modifying materials that can improve the performance of non-enzymatic electrochemical sensors.In a recent study,the combination of multi-element nanocomposites based on titanium dioxide(TiO_(2)),CNTs,and gold nanoparticles(AuNPs)resulted in the lowest detection limit of 3×10^(-5)μmol·L^(-1),reflecting the great potential of these materials for developing high-performance electrochemical sensors.The main conclusion of this article is the importance of a multidisciplinary approach in electrode material design to support the sensitivity and selectivity of TP detection.In addition,there is still a research gap in understanding TP’s more detailed oxidation mechanism,especially under pH variations and complex environments.Therefore,further research on electrode modification and analysis of the TP oxidation mechanism are urgently needed to improve the accuracy and sta-bility of the sensor while expanding its applications in pharmaceutical monitoring and medical diagnostics.By integrating various innovative materials and technical approaches,this review is expected to be an essential reference for developing efficient and affordable non-enzymatic electrochemical sensors.展开更多
Aiming at the requirement for high-precision tilt monitoring in the field of structural health monitoring(SHM),this paper proposes a sensitivity-enhanced tilt sensor based on a femtosecond fiber Bragg grating(FBG).Fir...Aiming at the requirement for high-precision tilt monitoring in the field of structural health monitoring(SHM),this paper proposes a sensitivity-enhanced tilt sensor based on a femtosecond fiber Bragg grating(FBG).Firstly,structural design of the tilt sensor was conducted based on static mechanics principles.By positioning the FBG away from the beam’s neutral axis,linear strain enhancement in the FBG was achieved,thereby improving sensor sensitivity.The relationship between FBG strain,applied force,and the offset distance from the neutral axis was established,determining the optimal distance corresponding to maximum strain.Based on this optimization scheme,a prototype of the tilt sensor was designed,fabricated,and experimentally tested.Experimental results show that the FBG offset distance yielding maximum sensitivity is 4.4 mm.Within a tilt angle range of−30°to 30°,the sensor achieved a sensitivity of 129.95 pm/°and a linearity of 0.9997.Compared to conventional FBG-based tilt sensors,both sensitivity and linearity were significantly improved.Furthermore,the sensor demonstrated excellent repeatability(error<0.94%),creep resistance(error<0.30%),and temperature stability(error<0.90%).These results demonstrate the sensor’s excellent potential for SHM applications.The sensor has been successfully deployed in an underground pipeline project,conducting long-term monitoring of tilt and deformation in the steel support structures,further proving its value for engineering safety monitoring.展开更多
The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtl...The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtle pressures has received less attention. The limitations in the inherent gauge factor in silicon, have led to the development of polymer and composite resistive sensitive elements. However,in the development of resistance sensing elements, the structure of composite elements with reinforcement core has not been used. The proposed PS had a composite sandwich structure consisting of a nanocomposite graphene layer covered by layers of PDMS at the bottom and on the top coupled with a polyimide(PI) core. Various tests were performed to analyze the PS. The primary design target was improved sensitivity, with a finite-element method(FEM) utilized to simulate the stress profile over piezoresistive elements and membrane deflection at various pressures. The PS manufacturing process is based on Laser-engraved graphene(LEG) technology and PDMS casting. Experimental data indicated that the manufactured PS exhibits a sensitivity of 67.28 mV/kPa for a pressure range of 30-300 Pa in ambient temperature.展开更多
For target tracking and localization in bearing-only sensor network,it is an essential and significant challenge to solve the problem of plug-and-play expansion while stably enhancing the accuracy of state estimation....For target tracking and localization in bearing-only sensor network,it is an essential and significant challenge to solve the problem of plug-and-play expansion while stably enhancing the accuracy of state estimation.This paper pro-poses a distributed state estimation method based on two-layer factor graph.Firstly,the measurement model of the bearing-only sensor network is constructed,and by investigating the observ-ability and the Cramer-Rao lower bound of the system model,the preconditions are analyzed.Subsequently,the location fac-tor graph and cubature information filtering algorithm of sensor node pairs are proposed for localized estimation.Building upon this foundation,the mechanism for propagating confidence mes-sages within the fusion factor graph is designed,and is extended to the entire sensor network to achieve global state estimation.Finally,groups of simulation experiments are con-ducted to compare and analyze the results,which verifies the rationality,effectiveness,and superiority of the proposed method.展开更多
目的观察咳喘镇定汤在小儿咳嗽变异性哮喘治疗中的作用及对患儿嗜酸性粒细胞计数(eosinophil count,EOS)、白介素-23(interleukin-23,IL-23)/辅助性T细胞17(helper T cells17,Th17)轴的影响。方法选取2020年8月—2023年2月收治的小儿咳...目的观察咳喘镇定汤在小儿咳嗽变异性哮喘治疗中的作用及对患儿嗜酸性粒细胞计数(eosinophil count,EOS)、白介素-23(interleukin-23,IL-23)/辅助性T细胞17(helper T cells17,Th17)轴的影响。方法选取2020年8月—2023年2月收治的小儿咳嗽变异性哮喘患儿104例,将患儿采用简单随机法分为两组。常规组给予止咳化痰、抗炎、平喘等常规治疗,咳喘镇定汤组在常规组基础上采用咳喘镇定汤辅助治疗。检测组间及组内T淋巴亚群、EOS、巨噬细胞炎症蛋白-1α(macrophage inflammatory protein-1α,MIP-1α)、Clara细胞分泌蛋白16(clara cell secreted protein 16,CC-16)、嗜酸细胞活化趋化因子(Eotaxin)、IL-23/Th17轴、小气道功能水平。评估组间及组内咳嗽症状评分、中医证候评分差异。统计组间疗效和不良反应。结果治疗前T淋巴亚群、CC-16、Eotaxin等差异无统计学意义(P>0.05)。两组治疗后CD_(8)^(+)、EOS、MIP-1α、Eotaxin降低,CC-16、CD_(4)^(+)、CD_(4)^(+)/CD_(8)^(+)升高,咳喘镇定汤组治疗后CD_(8)^(+)、EOS、MIP-1α、Eotaxin低于常规组,CC-16、CD_(4)^(+)、CD_(4)^(+)/CD_(8)^(+)高于常规组(P<0.05)。治疗前比较IL-23/Th17轴差异无统计学意义(P>0.05)。两组治疗后IL-23、Th17、白介素-17(interleukin-17,IL-17)降低,咳喘镇定汤组治疗后IL-23/Th17轴低于常规组(P<0.05)。治疗前相关评分无差异(P>0.05)。两组治疗后咳嗽症状评分、中医证候评分降低,咳喘镇定汤组治疗后咳嗽症状评分、中医症候评分低于常规组(P<0.05)。治疗前小气道功能无差异(P>0.05)。两组治疗后小气道功能升高,咳喘镇定汤组治疗后小气道功能高于常规组(P<0.05)。咳喘镇定汤组治愈13例,显效和有效共35例,总有效率92.31%高于常规组,差异有统计学意义(P<0.05)。结论咳喘镇定汤可通过调控小儿咳嗽变异性哮喘患儿IL-23/Th17轴,改善T淋巴亚群和小气道功能,减轻咳嗽症状,提高疗效。展开更多
基金the funding from Lembaga Penelitian dan Pengabdian Masyarakat(LPPM)Universitas Indonesia,by Riset Kolaborasi Indonesia(RKI)-World Class University(WCU)Program with grant number NKB-1067/UN2-RST/HKP.05.00/2023 and NKB-781/UN2.RST/HKP.05.00/2024.
文摘Detection of target analytes at low concentrations is significant in various fields,including pharmaceuticals,healthcare,and environmental protection.Theophylline(TP),a natural alkaloid used as a bronchodilator to treat respiratory disorders such as asthma,bronchitis,and emphysema,has a narrow therapeutic window with a safe plasma concentration ranging from 55.5-111.0μmol·L^(-1)in adults.Accurate monitoring of TP levels is essential because too low or too high can cause se-rious side effects.In this regard,non-enzymatic electrochemical sensors offer a practical solution with rapidity,portability,and high sensitivity.This article aims to provide a comprehensive review of the recent developments of non-enzymatic electrochemical sensors for TP detection,highlighting the basic principles,electro-oxidation mechanisms,catalytic effects,and the role of modifying materials on electrode performance.Carbon-based electrodes such as glassy carbon electrodes(GCEs),carbon paste electrodes(CPEs),and carbon screen-printed electrodes(SPCEs)have become the primary choices for non-enzymatic sensors due to their chemical stability,low cost,and flexibility in modification.This article identifies the sig-nificant contribution of various modifying materials,including nanomaterials such as carbon nanotubes(CNTs),graphene,metal oxides,and multi-element nanocomposites.These modifications enhance sensors’electron transfer,sensitivity,and selectivity in detecting TP at low concentrations in complex media such as blood plasma and pharmaceutical samples.The electro-oxidation mechanism of TP is also discussed in depth,emphasizing the hydroxyl and carbonyl reaction pathways strongly influenced by pH and electrode materials.These mechanisms guide the selection of the appropriate electrode ma-terial for a particular application.The main contribution of this article is to identify superior modifying materials that can improve the performance of non-enzymatic electrochemical sensors.In a recent study,the combination of multi-element nanocomposites based on titanium dioxide(TiO_(2)),CNTs,and gold nanoparticles(AuNPs)resulted in the lowest detection limit of 3×10^(-5)μmol·L^(-1),reflecting the great potential of these materials for developing high-performance electrochemical sensors.The main conclusion of this article is the importance of a multidisciplinary approach in electrode material design to support the sensitivity and selectivity of TP detection.In addition,there is still a research gap in understanding TP’s more detailed oxidation mechanism,especially under pH variations and complex environments.Therefore,further research on electrode modification and analysis of the TP oxidation mechanism are urgently needed to improve the accuracy and sta-bility of the sensor while expanding its applications in pharmaceutical monitoring and medical diagnostics.By integrating various innovative materials and technical approaches,this review is expected to be an essential reference for developing efficient and affordable non-enzymatic electrochemical sensors.
文摘Aiming at the requirement for high-precision tilt monitoring in the field of structural health monitoring(SHM),this paper proposes a sensitivity-enhanced tilt sensor based on a femtosecond fiber Bragg grating(FBG).Firstly,structural design of the tilt sensor was conducted based on static mechanics principles.By positioning the FBG away from the beam’s neutral axis,linear strain enhancement in the FBG was achieved,thereby improving sensor sensitivity.The relationship between FBG strain,applied force,and the offset distance from the neutral axis was established,determining the optimal distance corresponding to maximum strain.Based on this optimization scheme,a prototype of the tilt sensor was designed,fabricated,and experimentally tested.Experimental results show that the FBG offset distance yielding maximum sensitivity is 4.4 mm.Within a tilt angle range of−30°to 30°,the sensor achieved a sensitivity of 129.95 pm/°and a linearity of 0.9997.Compared to conventional FBG-based tilt sensors,both sensitivity and linearity were significantly improved.Furthermore,the sensor demonstrated excellent repeatability(error<0.94%),creep resistance(error<0.30%),and temperature stability(error<0.90%).These results demonstrate the sensor’s excellent potential for SHM applications.The sensor has been successfully deployed in an underground pipeline project,conducting long-term monitoring of tilt and deformation in the steel support structures,further proving its value for engineering safety monitoring.
文摘The Design and manufacturing of a noble piezoresistive pressure sensor(PS) for subtle pressures(<1 kPa) were presented. Meanwhile, in the studies conducted in the field of pressure sensors, the measurement of subtle pressures has received less attention. The limitations in the inherent gauge factor in silicon, have led to the development of polymer and composite resistive sensitive elements. However,in the development of resistance sensing elements, the structure of composite elements with reinforcement core has not been used. The proposed PS had a composite sandwich structure consisting of a nanocomposite graphene layer covered by layers of PDMS at the bottom and on the top coupled with a polyimide(PI) core. Various tests were performed to analyze the PS. The primary design target was improved sensitivity, with a finite-element method(FEM) utilized to simulate the stress profile over piezoresistive elements and membrane deflection at various pressures. The PS manufacturing process is based on Laser-engraved graphene(LEG) technology and PDMS casting. Experimental data indicated that the manufactured PS exhibits a sensitivity of 67.28 mV/kPa for a pressure range of 30-300 Pa in ambient temperature.
基金supported by the National Natural Science Foundation of China(62176214).
文摘For target tracking and localization in bearing-only sensor network,it is an essential and significant challenge to solve the problem of plug-and-play expansion while stably enhancing the accuracy of state estimation.This paper pro-poses a distributed state estimation method based on two-layer factor graph.Firstly,the measurement model of the bearing-only sensor network is constructed,and by investigating the observ-ability and the Cramer-Rao lower bound of the system model,the preconditions are analyzed.Subsequently,the location fac-tor graph and cubature information filtering algorithm of sensor node pairs are proposed for localized estimation.Building upon this foundation,the mechanism for propagating confidence mes-sages within the fusion factor graph is designed,and is extended to the entire sensor network to achieve global state estimation.Finally,groups of simulation experiments are con-ducted to compare and analyze the results,which verifies the rationality,effectiveness,and superiority of the proposed method.
文摘目的观察咳喘镇定汤在小儿咳嗽变异性哮喘治疗中的作用及对患儿嗜酸性粒细胞计数(eosinophil count,EOS)、白介素-23(interleukin-23,IL-23)/辅助性T细胞17(helper T cells17,Th17)轴的影响。方法选取2020年8月—2023年2月收治的小儿咳嗽变异性哮喘患儿104例,将患儿采用简单随机法分为两组。常规组给予止咳化痰、抗炎、平喘等常规治疗,咳喘镇定汤组在常规组基础上采用咳喘镇定汤辅助治疗。检测组间及组内T淋巴亚群、EOS、巨噬细胞炎症蛋白-1α(macrophage inflammatory protein-1α,MIP-1α)、Clara细胞分泌蛋白16(clara cell secreted protein 16,CC-16)、嗜酸细胞活化趋化因子(Eotaxin)、IL-23/Th17轴、小气道功能水平。评估组间及组内咳嗽症状评分、中医证候评分差异。统计组间疗效和不良反应。结果治疗前T淋巴亚群、CC-16、Eotaxin等差异无统计学意义(P>0.05)。两组治疗后CD_(8)^(+)、EOS、MIP-1α、Eotaxin降低,CC-16、CD_(4)^(+)、CD_(4)^(+)/CD_(8)^(+)升高,咳喘镇定汤组治疗后CD_(8)^(+)、EOS、MIP-1α、Eotaxin低于常规组,CC-16、CD_(4)^(+)、CD_(4)^(+)/CD_(8)^(+)高于常规组(P<0.05)。治疗前比较IL-23/Th17轴差异无统计学意义(P>0.05)。两组治疗后IL-23、Th17、白介素-17(interleukin-17,IL-17)降低,咳喘镇定汤组治疗后IL-23/Th17轴低于常规组(P<0.05)。治疗前相关评分无差异(P>0.05)。两组治疗后咳嗽症状评分、中医证候评分降低,咳喘镇定汤组治疗后咳嗽症状评分、中医症候评分低于常规组(P<0.05)。治疗前小气道功能无差异(P>0.05)。两组治疗后小气道功能升高,咳喘镇定汤组治疗后小气道功能高于常规组(P<0.05)。咳喘镇定汤组治愈13例,显效和有效共35例,总有效率92.31%高于常规组,差异有统计学意义(P<0.05)。结论咳喘镇定汤可通过调控小儿咳嗽变异性哮喘患儿IL-23/Th17轴,改善T淋巴亚群和小气道功能,减轻咳嗽症状,提高疗效。
