Las nanoestructuras de ZnO y sus aplicaciones como sensor de gas H2S / The ZnO nanostructures and their applications as a H2S gas sensor

RESUMEN Existe un interés global en la detección de gases tóxicos, para la protección del medio ambiente y los seres humanos. Se han desarrollado múltiples estudios enfocados en el uso de sensores de gases basados en óxidos metálicos, como es el óxido de zinc (ZnO), el cual presenta propiedades electrónicas específicas como sensor de gases por ser un semiconductor tipo n y bajo costo de producción. El objetivo de este trabajo fue analizar el uso de nanoestructuras de ZnO, para la fabricación de sensores del gas ácido sulfhídrico (H2S), así como las técnicas de obtención más comunes de dichas estructuras. Las características de las nanoestructuras de óxido de zinc (NE´s-ZnO) varían por efecto del método de obtención, generando diferentes morfologías y tamaño, que impactan en la capacidad de detección de gas (0.5 ppm a 600 ppm) y en el rango de temperatura que se requiere. Los avances en la generación de diversas NE´s-ZnO facilitarán la posibilidad de generar sensores que puedan ser utilizados en detectores portátiles y operen a temperatura ambiente, lo cual es un reto actual.

ABSTRACT There is a global interest in the detection of toxic gases for the protection of the environment and human beings, using low-cost and easy-to-use sensors. Multiple studies have focused on the use of gas detectors based on metal oxides, such as zinc oxide (ZnO), which has specific electronic properties as a gas detector because it is an n-type semiconductor and it has a low production cost. The objective of this work was to analyze the use of ZnO nanostructures for the manufacturing of hydrogen sulfide (H2S) gas sensors, as well as the most common techniques for obtaining these structures. The characteristics of zinc oxide nanostructures (NE´s-ZnO) vary due to the effect of the obtaining method, generating different morphologies and sizes, which impacts gas detection performance (0.5 ppm up to 600 ppm) and in the temperature range that is required. Advances in the design of various NE's-ZnO will have the possibility of generating sensors that can be used in portable detectors and operate at room temperature, which is a current challenge.

Tumor cell membrane-coated continuous electrochemical sensor for GLUT1 inhibitor screening / 药物分析学报

Glucose transporter 1(GLUT1)overexpression in tumor cells is a potential target for drug therapy,but few studies have reported screening GLUT1 inhibitors from natural or synthetic compounds.With cur-rent analysis techniques,it is difficult to accurately monitor the GLUT1 inhibitory effect of drug molecules in real-time.We developed a cell membrane-based glucose sensor(CMGS)that integrated a hydrogel electrode with tumor cell membranes to monitor GLUT1 transmembrane transport and screen for GLUT1 inhibitors in traditional Chinese medicines(TCMs).CMGS is compatible with cell membranes of various origins,including different types of tumors and cell lines with GLUT1 expression knocked down by small interfering RNA or small molecules.Based on CMGS continuous monitoring technique,we inves-tigated the glucose transport kinetics of cell membranes with varying levels of GLUT1 expression.We used CMGS to determine the GLUT1-inhibitory effects of drug monomers with similar structures from Scutellaria baicalensis and catechins families.Results were consistent with those of the cellular glucose uptake test and molecular-docking simulation.CMGS could accurately screen drug molecules in TCMs that inhibit GLUT1,providing a new strategy for studying transmembrane protein-receptor interactions.

Evaluation method of dynamic postural stability for functional ankle instability based on acceleration signals / 中国康复理论与实践

ObjectiveTo compare the retest reliability and discriminant validity of dynamic postural stability indices for functional ankle instability (FAI) obtained by different algorithms based on acceleration signals at different positions of human body. MethodsFrom April to June, 2021, 21 subjects with unilateral FAI and 21 subjects with normal ankle were recruited. Three inertial sensors were attached to the waist points, knee and ankle positions. The ground reaction force (GRF) and kinematics data of the subjects in multi-direction single leg landing test were collected synchronously by 3D force plate and inertial sensors. The unbounded third order polynomial (UTOP) fitting method was used to calculate the stability time, and the root mean square was used to caculate the stability index. ResultsMost of the indicators calculated based on acceleration signal correlated with that based on GRF with low coefficient (|r| = 0.116 to 0.368, P < 0.05). The stability time and stability index based on the acceleration signals of different positions of human body showed low to high retest reliability (CMC 0.30 to 0.91). For the females, among the stability time based on acceleration signal, eleven indexes achieved average to very high discriminant validity (AUC = 0.702 to 0.942, P < 0.05); eight of the stability indexes reached general level of discriminant validity (AUC = 0.717 to 0.782, P < 0.05). No algorithms achieved good discriminant effect in male subjects. ConclusionBased on the acceleration signal of waist point in single-leg landing stability test, the stability time calculated by UTOP algorithm can evaluate the dynamic postural stability of female FAI patients with high discriminant validity and medium to high retest reliability.

Recent progress on detection techniques for human hormones / 药学学报

Human hormones at trace levels play a vital role in the regulation of a variety of functions and systems in the body, and an imbalance in hormone levels can lead to the emergence and development of diverse diseases. Therefore, the development of reliable sample pretreatment methods and sensitive and accurate analytical techniques for human hormone detection could contribute to the prevention, diagnosis and treatment of diseases, providing significant improvement for human health. Human samples which are usually used to detecting hormones, such as blood, saliva, urine and other matrix are more complex, so sample pretreatment is an important step to ensure the accuracy and reliability in the detection of hormones. In this review three common sample pretreatment methods including solid phase extraction (SPE), liquid-liquid extraction (LLE) and protein precipitation (PP) methods are discussed. Then, recent research progress in conventional techniques like liquid/gas chromatography and liquid/gas chromatography-mass spectrometry (LC/GC-MS/MS), as well as some novel strategies, such as immunoassay including chemiluminescence immunoassay (CLIA), lateral-flow immunoassay (LFIA) and time-resolved fluoroimmunoassay (TRFIA), and sensor technology including electrochemical (EC), fluorescent (FL) and surface-enhanced Raman scattering (SERS) sensors, and microfluidic chip analysis are discussed for human hormone detection. Finally, the future perspective on the use of these methods for hormone detection is considered. It is hoped to provide powerful insights to researchers for the relevant researches.

Regulating anaerobic metabolism and promoting myocardial ischemia-hypoxia injury by diesel particulate matter and its key component benzoapyrene via targeting oxygen sensors / 环境与职业医学

Background The exposure to diesel particulate matter (DPM) and its polycyclic aromatic hydrocarbons (PAH) is closely related to the morbidity and mortality of ischemic heart disease (IHD). However, it is unclear what key components and targets of DPM exposure involve in myocardial ischemia-hypoxia injury and associated mechanisms. Objective To identify key PAH components of DPM that act on myocardial hypoxic injury, andclarify the role of oxygen sensors-regulated anaerobic metabolism in DPM and key components-induced hypoxic injury and the targets of the key PAH components. Methods Human cardiomyocyte cell line AC16 cells were exposed to 0, 1, 5, and 10 μg·mL−1 DPM in a high glucose DMEM medium with 10% fetal bovine serum (FBS) (HGM) or low FBS (0.5%) in high glucose DMEM medium (LFM), for 12 h under 2% O2, and expression of hypoxia-inducible factor-1α (HIF-1α), Bax, and Cleaved-caspase3 was determined by Western blotting. Under normal condition, the cell viability was detected after PAH exposure for 12 h. Under the condition of ischemia-hypoxia model, cells were exposed to 0, 0.005, 0.5, and 5 µg·mL−1 PAH for 12 h, and the protein expression of HIF-1α, Bax, and Cleaved-caspase3 was determined. After exposure to DPM or PAH for 12 h, the contents of pyruvate and lactate in cells were detected. Pretreatment with glycolysis inhibitor GSK2837808A was used to explore the role of glycolysis in DPM and benzo[a]pyrene (BaP)-induced hypoxia injury. A molecular docking technique was used to analyze the binding affinity between PAH and oxygen sensors (prolyl hydroxylase domain-containing protein 2, PHD2, and factor-inhibiting hypoxia-inducible factor 1, FIH1), and the protein levels of PHD2, FIH1, and hydroxyl-HIF-1-alpha (OH-HIF-1α) after the DPM or BaP treatment were further determined. Results Under hypoxia, DPM exposure in the LFM induced the expression of HIF-1α, Bax, and Cleaved-caspase3 (P<0.01). Therefore, hypoxia and LFM were selected as the basic ischemia and hypoxia condition. Except for anthracene (Ant) (P>0.05), other PAH decreased cell viability when the concentration was above 1 μg·mL−1 (P<0.05). All concentrations of BaP induced the expression of HIF-1α protein (P<0.05), and the protein levels of Bax and Cleaved-caspase3 were up-regulated after the 0.5 and 5 µg·mL−1 BaP exposure (P<0.01). After exposure to DPM (1, 5 and 10 μg·mL−1) or BaP (0.5 and 5 μg·mL−1), the intracellular pyruvate and lactate contents increased (P<0.05). The glycolysis inhibitor co-treatment decreased the levels of HIF-1α, Bax, and Cleaved-caspase3 proteins compared with the DPM or BaP exposure group for 12 h (P＜0.05). The binding abilities of the five PAHs to the oxygen sensors PHD2 and FIH1 were strong, and BaP was the strongest. Although the DPM or BaP exposure had no effects on the protein levels of PHD2 and FIH1 in AC16 cells (P＜0.05), the protein level of OH-HIF-1α was decreased (P＜0.01). Conclusion BaP exposure can promote hypoxia and injury of myocardial cells and is the key PAH component of DPM that induces myocardial ischemia and hypoxia injury. BaP exposure inhibits the hydroxylation function of PHD2 on HIF-1α by combining with PHD2, decreases the level of OH-HIF-1α and induces HIF-1α accumulation. And then HIF-1α promotes anaerobic metabolism and accelerates ischemia and hypoxia injury of myocardial cells.

A monitoring aid for movement disorder rehabilitation / 国际生物医学工程杂志

Objective:To design a motor impairment rehabilitation monitoring aid for the assessment of motor impairment in patients who do not have or have difficulty walking independently.Methods:An assistive device vehicle was designed, equipped with an accelerometer and a six-dimensional force sensor. The normal walking (NW) group and abnormal walking group were set up, in which the abnormal walking group included moderate abnormal walking (MA) group, moderate abnormal walking with the aid of the assistive vehicle (MA-V) group, severe abnormal walking (SA) group, and severe abnormal walking with the aid of the assistive vehicle (SA-V) group. In the MA-V group, the range of knee movement was adjusted from 0 to 30°, and in the SA group, the knee joint was completely unbending. The gait cycles, peak and mean acceleration values of the right and left legs were evaluated by accelerometers, and changes in the upper limb forces were assessed by six-dimensional force transducers.Results:For the moderate impairment group, the difference in gait cycle between the MA and MA-V groups was not statistically significant ( P>0.05), and the gait cycle in the MA-V group was slightly greater than that in the MA group. For the severe injury group, the gait cycle of the SA-V group was lower than that of the SA group, and the difference was statistically significant ( P<0.01). For all abnormal groups, the mean and peak acceleration of the left leg were greater than that of the right leg, and the difference between the peak acceleration of the left leg and that of the right leg was statistically significant ( P<0.05). In the abnormal walking pattern, the mean (absolute) value of the left hand force was greater than that of the right hand, especially in the Z-axis. The standard deviations of the combined forces on the left side for the NW, MA-V, and SA-V groups were 2.759, 8.297, and 13.118 N, respectively. The SA-V group had the highest dispersion in the force scatter plot, while the NW group had a better concentration. Conclusions:An assistive vehicle equipped with an accelerometer and a six-dimensional force sensor was designed to help physicians in the assessment and rehabilitation of motor disorders.

An Algorithm for Measuring Vertical Ground Reaction Force Based on Insole Sensors / 医用生物力学

Objective A practical and highly accurate algorithm for dynamic monitoring of plantar pressure was proposed, the magnitude of vertical ground reaction force (vGRF) during walking was measured by a capacitive insole sensor, and reliability of the prediction accuracy was verified. Methods Four healthy male subjects were require to wear capacitive insole sensors, and their fast walking and slow walking data were collected by Kistler three-dimensional (3D) force platform. The data collected by the capacitive insole sensors were pixelated, and then the processed data were fed into a residual neural network, ResNet18, to obtain high-precision vGRF. Results Compared with analysis of the data collected from Kister force platform, the normalized root mean square error (NRMSE) for fast walking and slow walking were 8.40% and 6.54%, respectively, and the Pearman correlation coefficient was larger than 0.96. Conclusions This study provides a novel algorithm for dynamic measurement of GRF in mobile scenarios, which can be used for estimation of complete GRF outside the laboratory without being constrained by the number and location of force plates. Potential application areas include gait analysis and efficient capture of pathological gaits.

Development of Shoelace Tensile Test System Based on Micro Sensors and Reliability Study / 医用生物力学

Objective To design and verify the reliability of a shoelace tensile test system. Methods Incremental loads of 0-196 N were applied to three tension sensors, each load was repeated nine times, with the load removed and interval of 30 s during the repeated tests. Then output voltage of the sensors under each load was collected. Linear regression analysis was used to explore linear relationship between the collected voltage signal and the incremental load. Accuracy, precision and consistency intervals were used to verify consistency of the measured values with the true load. Bland-Altman analysis and intra-group correlation coefficient (ICC) analysis were used to verify the repeatability and reliability of the tensile sensor. Results There was a significant linear correlation between output voltage signal of the sensors and the load (P< 0. 000 1, R2= 0. 999 9), and ICC of three sensors was above 0. 999 (P<0. 000 1). The mean values of the coefficients of variation of the measured values for three tensile sensors under different loads were 0. 003 8, 0. 002 2 and 0. 003 5, respectively. Conclusions The shoelace tensile test system has high reliability and can be used for real-time acquisition of shoelace tension.

The screening model for dopamine receptor agonists by a dopamine sensor / 药学学报

Parkinson's disease (PD) is a degenerative disease of the central nervous system due to the loss or death of dopaminergic neurons in the substantia nigra. Clinically, levodopa is the most effective and commonly used drug for PD treatment. However, long-term levodopa therapy is prone to motor complications and other side effects caused by excessive peripheral dopamine production, which has become an urgent problem to be solved in PD treatment. Dopamine receptor (DR) agonists are similar to dopamine. They can directly stimulate postsynaptic dopamine receptors, produce the same effect as dopamine, delay the application of levodopa as much as possible, and reduce complications caused by long-term use of levodopa. Therefore, screening effective dopamine receptor agonists has become a key issue in the study and treatment of PD. In order to establish a rapid, stable and reliable method for dopamine receptor agonist screening, this study used the human dopamine receptor 2 (DRD2) gene fused with a circular permuted EGFP (cpEGFP) to construct a recombinant gene, packaged with lentiviral vector, and the vector replaced the parted inner transmembrane domain of the third intracellular loop (ICL3) of genetically-encoded GPCR-activation based (GRAB) sensors. The fluorescence of GPCR-fused cpEGFP is regulated by conformational changes mediated by the interaction of dopamine receptor agonists with GPCRs without altering GPCR activity. The HEK293T cells were infected with viral vector, screened by puromycin to select highly expressed cells. Dopamine receptor agonists (including dopamine, bromocriptine mesylate, cabergoline, pramipexole) were used as positive drugs to explore the best screening and detection conditions, establishing a stable model to evaluate the dopamine receptor agonist. The results showed that the optimal filter for the dopamine receptor agonist in this study was the cell seeding count of 7×104, and the effective concentration of the positive drug was 1-100 µmol·L-1. In addition, pretreated with 10 µmol·L-1 dopamine receptor antagonists (including chlorprothixol hydrochloride, domperidone, and sulpiride), the positive fluorescence signal of overexpressed DRD2-cpEGFP HEK293T cells could not be detected when exposed to 10 µmol·L-1 dopamine receptor agonists, which proved that dopamine receptor antagonists could block the activity of dopamine receptor agonists, so they cannot activate dopamine receptor allosteric, indicating that the model has good specificity and can also be used for the screening and detection of new dopamine receptor antagonists. In summary, the study constructs a stable dopamine sensor detection system, which can effectively screen potential dopamine receptor agonists. The operation procedures are simple and rapid. And it can be used for a large-scale screening providing a fundamental methodology for drug development and PD treatment targeted on DRD2.

Microwave sensor for recognition of abnormal nodule tissue on body surface / 生物医学工程学杂志

For the detection and identification of abnormal nodular tissues on the body surface, a microwave sensor structure loaded with a spiral resonator is proposed in this paper, a sensor simulation model is established using HFSS software, the structural parameters are optimized, and the actual sensor is fabricated. The S21 parameters of the tissue were obtained when nodules appeared by simulation, and the characteristic relationship between the difference of S21 parameters with position was analyzed and tested experimentally. The results showed that when nodules were present in normal tissues, the curve of S21 parameter difference with position change had obvious inverted bimodal characteristics, and the extreme value of S21 parameter difference appeared when the sensor was directly above the nodules, which was easy to identify the position of nodules. It provides an objective detection tool for the identification of abnormal nodular tissues on the body surface.

Continuous Blood Glucose Monitoring:Technological Progress and Application Extension / 中国医疗器械杂志

Continuous glucose monitoring (CGM) technology developed rapidly in recent years, and new products came out all the time. Nowadays, CGM plays an important role in diabetes management and has been recommended by various guideline all over the world. CGM equipment classification, progress on glucose sensor technology, and the new application and expansion of CGM technology in the field of diabetes and non-diabetes were briefly introduced in the study.

Design and Research of Wearable Fall Protection Device for the Elderly / 中国医疗器械杂志

A protective device was designed that can be worn on the elderly, which consists of protective airbag, control box and protective mechanism. The combined acceleration, combined angular velocity and human posture angle are selected as the parameters to determine the fall, and the threshold algorithm and SVM algorithm are used to detect the fall. The protective mechanism is an inflatable device based on CO2 compressed air cylinder, and the equal-width cam structure is applied to its transmission part to improve the puncture efficiency of the compressed gas cylinder. A fall experiment was designed to obtain the combined acceleration and angular velocity eigenvalues of fall actions (forward fall, backward fall and lateral fall) and daily activities (sitting-standing, walking, jogging and walking up and down stairs), showing that the specificity and sensitivity of the protection module reached 92.1% and 84.4% respectively, which verified the feasibility of the fall protection device.

A descrição teórica da determinação eletroquímica do fármaco perilartina, assistida pelo oxihidróxido de cobalto, emparelhado com o seu dióxido

Introdução: perilartina é um adoçante natural potente, considerado 2000 vezes mais doce que o açúcar comum. Ela pode ser alérgica para algumas pessoas. Além disso, ela se usa apenas no Japão, o que pressupõe a possibilidade de adulterar produtos japoneses sem o seu uso. Assim, o desenvolvimento de um método eficiente da sua determinação qualificativa e quantificação é realmente atual. Metodologia: um modelo matemático de um processo anódico foi desenvolvido e analisado mediante a teoria de estabilidade linear e análise de bifurcações. O modelo inclui os cenários mais prováveis do andamento do processo eletroanalítico. Resultados: a perilartina é oxidada no meio básico, formando o poliol e o sal do "pseudoácido" correspondente, o que contribui fortemente para a força iônica da dupla camada elétrica. Isto pode ser responsável pela aparição das instabilidades oscilatória e monotônica no processo eletroanalítico. Conclusão: malgrado o supracitado, o compósito é um modificador eficiente para a determinação eletroquímica da perilartina no meio básico.

Introducción: perilartina es un edulcorante natural potente, considerado 2000 veces más dulce que el azúcar común. Esta puede causar alergia a algunas personas. Además, ella solo se usa en Japón, lo que presupone la posibilidad de falsificar productos japoneses sin su uso. Así, el desarrollo de un método eficiente de su determinación cuantitativa y cualitativa es realmente actual. Metodología: un modelo matemático de un proceso anódico fue desarrollado y analizado mediante la teoría de estabilidad lineal e análisis de bifurcaciones. El modelo incluye los escenarios más probables del curso del proceso electroanalítico. Resultados: la perilartinase oxida en el medio básico, formando el poliol y la sal del "pseudoácido" correspondiente, lo que contribuye fuertemente para la fuerza iónica de la doble capa eléctrica. Esto puede ser responsable por la aparición de las inestabilidades oscilatoria y monotónica en el proceso electroanalítico. Conclusión: a pesar de lo mencionado, el compuesto es un modificador eficaz para la determinación electroquímica de la perilartina en el medio básico.

SUMMARY Introduction: Perillartine is a strong natural sweetener, considered 2000 as sweet as a common sugar. It may be allergic to some people. Also, it is used only in Japan, which may presuppose the possibility of falsify Japanese products without its use. Thus the development of an eficiente method of its quantitative and qualitative determination is really actual. Methodology: A mathematical model of an anodic process has been developed and analyzed by means of linear stability theory and bifurcation analysis. The model includes the most probable scenarios of the course of the electroanalytical process. Results: Perillartine is oxidized in basic media, yielding the polyol and the correspondent pseudoacid salt, which strongly contributes to the double electric layer ionic force. This may be responsible for the oscillatory and monotonic instabilities appearance in the electroanalytical process. Conclusion: Despite of the above mentioned statements, the composite is na efficient modifier for the electrochemical determination of perillartine in basic media.

“Oxygen Pheriwala: ” An Innovative Model for SARS-CoV-2 Screening in Resource-Limited Settings

The second wave of SARS?CoV?2 infection came as a hypoxic emergency and situation became worse in rural India, where undiagnosed COVID-19 patients died without any diagnosis or intervention. The primary aim of this innovative model was the early diagnosis of suspected SARS?CoV?2 cases, providing empirical treatment and timely referral to appropriate COVID care facilities. Fever was measured with infrared thermometer and oxygen saturation level with pulse oximeter. A total of 8203 people were screened, of which 274 persons were febrile and 69 (25%) were hypoxic too. Sixty?four out of 69 (93%) patients turned COVID?19 positive on reverse transcription?polymerase chain reaction. At the end of 3 weeks, 48/64 (75%) patients were successfully discharged. This model can be easily implemented in resource?limited regions to identify and prioritize the patients not only in this pandemic but also in outbreak of other communicable diseases.

Descripción teórica del desempeño electroanalítico del material compuesto de oxihidróxido de vanadio con el colorante escuárico en la detección de la carfedona

Introducción: en este trabajo se evalúa desde el punto de vista mecanístico teórico el comportamiento electroanalítico del compuesto oxihidróxido de vanadio-colorante escuárico en la detección de la carfedona. El proceso electroanalítico incluye la formación de dos formas de vanadio tetravalente, incluyendo el dióxido de vanadio e ion vanadilo. Método: un mecanismo, capaz de describir el comportamiento del sensor, ha sido sugerido y un modelo matemático fue desarrollado y analizado mediante la teoría de estabilidad lineal y análisis de bifurcaciones. Resultados: el análisis del modelo ha probado que la dependencia lineal entre la concentración del fármaco y el parámetro electroquímico se mantiene firme en la ancha región topo-lógica de parámetros. Las inestabilidades oscilatoria y monotónica suelen realizarse cuando son causadas por influencias fuertes de las etapas química y electroquímica en la capacitancia de la doble capa eléctrica. Conclusiones: el compuesto de nano-partículas de oxihidróxido de vanadio (estabilizadas con el colorante escuárico) puede servir como un modificador eficiente de electrodo para la detección de la carfedona. El oxihidróxido de vanadio desempeña funciones de sustancia activa y el colorante, de la mediadora.

SUMMARY Introduction: In this work, the electroanalytical behavor of the vanadium oxyhydroxide-squaraine dye composite for the carfedon detection is evaluated. The electroanalytical process includes the formation of two tetravalent vanadium forms, including vanadium dioxide and vanadylion. Methods: A mechanism, capable to describe the sensor behavior, has been suggested, and the correspondent mathematical model has been developed and analyzed by means of the linear stability theory and bifurcation analysis. Results: The model analysis has proved that the linear dependence between the drug concentration and the concentration is firmly maintained in a wide topological parameter region. As for the oscillatory and monotonic instabilities, they may be realized, being caused by strong influences of the chemical and electrochemical stages on double electric layer capacitance. Conclusions: The vanadium oxyhydroxide composite with the squaraine dye may serve as an efficient electrode modifier for carfedone determination. The vanadium oxyhydroxide works as an active substance and the dye as a mediator.

Introdução: neste trabalho, avalia-se, do ponto de vista mecanístico teórico, o comportamento eletroanalítico do compósito oxihidróxido do vanádio-corante esquárico na detecção da carfedona. O processo eletroanalítico inclui a formação de duas formas do vanádio tetravalente, incluindo o dióxido de vanádio e íon vanadila. Método: um mecanismo, capaz de descrever o comportamento do sensor, tem sido sugerido e um modelo matemático correspondente, desenvolvido e analisado por meio da teoria de estabilidade linear e análise de bifurcações. Resultados: a análise do modelo tem provado que a dependência linear entre a concentração do fármaco e o parâmetro eletroquímico se mantém firme numa ampla região topológica de parâmetros. Já as instabilidades oscilatória e monotônica soem realizar-se, sendo causadas pelas influências fortes das etapas química e electroquímica na capacitância da dupla camada elétrica. Conclusões: o compósito de nanopartículas do oxihidróxido de vanádio, estabilizadas pelo corante esquárico, pode servir de um modificador eficaz para a detecção da carfedona. O oxihidróxido de vanádio desempenha as funções de substância ativa, e o corante, de mediador.

Biophysical characteristics of soybean estimated by remote sensing associated with artificial intelligence

The biophysical characteristics of vegetative canopies, such as biomass, height, and canopy diameter, are of paramount importance for the study of the development and productive behavior of crops. Faced with a scarcity of studies aimed at estimating these parameters, the objective of this study was to evaluate the performance of artificial neural networks (ANNs) applied to Proximal Remote Sensing (PRS) to estimate biophysical characteristics of soybean culture. The data used to train and validate the ANNs came from an experiment composed of 65 plots with 30 x 30 m mesh, its development was carried out in the 2016/2017 crop in the Brazilian agricultural area. The evaluations were carried out at 30, 45, 60, and 75 days after sowing (DAS), monitoring the spatial and temporal variability of the biophysical characteristics of the soybean crop. Vegetation indexes were collected using canopy sensors. The accuracy and precision were determined by the coefficient of determination (R2) and the error of the forecasts by MAPE (Mean Absolute Percentage Error). PRS and ANNs showed high potential for application in agriculture, since they obtained good performance in the estimation of height (R2 = 0.89) and canopy diameter (R2 = 0.96), being fresh biomass (R2 =0.98) and dry biomass (R2 = 0.97) were the best-estimated variables.

A SIMPLE GIBBS SAMPLER FOR THE STATE ESTIMATION IN WIRELESS COMMUNICATIONS

In the recent years, wireless communications are extremely useful in many disciplines including health monitoring, environment monitoring, signal processing etc. State estimation and prediction are quite challenging tasks in wireless communications. Traditionally, in the literature, dynamic state-space models have been used for the state estimation and predic- tion purpose. The estimation method is based on Kalman-Filter which is computationally demanding. In this work, we consider computationally simpler Gibbs sampler algorithm for the state estimation. We consider three different cases, (i) continuous state values, (ii) binary (0/1) state values, and (iii) categorical state values with more than two categories. We consider a simple linear model for the prediction purpose, and the underlying regression coefficients are estimated by Gibbs sampler. We compute the misclassification proportions for assessing the practical usefulness of our estimation approach. Areal dataset where 200 wireless sensor nodes are used for measuring the temperature of a chamber is analysed in this work

Knee Joint Moment Estimation During Walking via Wearable Inertial Sensor Network / 医用生物力学

Objective To estimate knee adduction moment (KAM) and knee flexion moment (KFM) under different gait test conditions via an inertial sensor network (ISN). Methods Twelve healthy young male subjects wore eight inertial sensors (located in the trunk, pelvis, both thighs, both shanks, both feet) and walked under different test conditions (changing foot progression angle, trunk sway angle, step width and walking speed). An ISN was used to extract biomechanical features as the input of recurrent neural network (RNN), so as to estimate the KAM and KFM. Results The overall KAM estimation accuracy: relative root mean square error (rRMSE) was 8.54% and r=0.84. The overall KFM estimation accuracy was rRMSE=6.40% and r=0.94. Conclusions The model can be used as the basis for load estimation of knee joints out of the lab and its potential application includes gait training and rehabilitation assessment after knee surgery.

Research Progress on Enzyme-free Blood Glucose Sensor / 中国医疗器械杂志

Blood glucose monitoring is of great significance to diabetic patients, and the development of rapid, accurate and real-time glucose detection technology has become a research hotspot nowadays. This study introduces the concept and classification of the enzyme-free glucose sensor, expounds enzymefree glucose sensor electrode characterization methods and the application progress of different materials in enzyme-free blood glucose sensors. Meanwhile, some problems of enzyme-free glucose sensor existing in the current research and its future application prospects also will be discussed.

Discussion on Testing and Standard of Blood Pressure Sensor at the Tip of Catheter / 中国医疗器械杂志

With the implementation of the new policy for coronary stent centralized volume purchasing in China, the blood pressure sensor at the tip of the catheter, as one of the essential medical instruments for the diagnosis and treatment of coronary artery disease, will meet the new development opportunity of the industry, a number of medical device companies will actively participate in the development and registration of the catheter tip blood pressure sensor. As an invasive blood pressure sensor, the catheter tip blood pressure sensor should meet the current effective industry standard YY 0781-2010, however, there are many problems when using YY 0781-2010 as a blood pressure sensor because of the difference of product structure and working mode. In this paper, the problems about "Operation Manual", "electrical performance" and "safety requirement" in the course of carrying out YY 0781- 2010 with the blood pressure sensor on the tip of catheter are discussed and analyzed in detail, hope to provide some inspiration for more research and development enterprises of blood pressure sensors on the tip of catheters and inspectors of medical device testing institutions, also hope to be able to contribute to the high-quality development of blood pressure sensor industry at the tip of the Catheter.