Drogas emergentes: detección mediante sensores electroquímicos

La cantidad de nuevas sustancias psicoactivas (NSP) aumenta en el mercado global cada año. El uso de tecnologías para la producción y la comercialización de las sustancias sintéticas y una demanda exigente de efectos psicotrópicos más potentes son algunos de los factores que contribuyen al incremento de una oferta más variada, así como a la cantidad de consumidores de algún tipo de droga. El desarrollo de herramientas analíticas fiables con capacidad de respuesta in situ para una evaluación preliminar contribuye, significativamente, con la generación de información para atender casos de intoxicaciones, aplicar correctamente la legislación de los países e, inclusive, aportar datos reales para una reclasificación más objetiva de las drogas basada en criterios científicos. Los sensores electroquímicos han ganado terreno en áreas de las ciencias forenses como la toxicología. El uso de tecnologías especializadas para crear electrodos miniaturizados con modificaciones, principalmente con materiales nanoestructurados, guía el desarrollo de dispositivos portátiles de fácil manipulación, altamente versátiles y que requieren micro-cantidades de la muestra. Asimismo, algunos sensores electroquímicos presentan parámetros de desempeño -como límites de detección (LOD) de hasta 0,608 pg/mL, sensibilidad y precisión- que son analíticamente comparables, bajo ciertas condiciones, con las metodologías convencionales acopladas con la espectrometría de masas, las cuales muestran LOD del orden de magnitud entre 10-9 g/mL y 10-12 g/mL para la determinación de algunas drogas. Esta revisión se enfoca en la aplicación y comparación analítica de los sensores electroquímicos voltamperométricos para la determinación de bencilpiperazina (BZP), meta-clorofenilpiperazina (mCPP), 25B-NBO-Me, dimetiltriptamina (DMT), mefedrona (4-MMC), 4-metiletcatinona (4-MEC) y fentanilo (FYL) en representación de las drogas emergentes que se pueden conseguir actualmente en el mercado de las sustancias psicoactivas.

The number of new psychoactive substances (NPS) is increasing on the drug global market every year. New technologies for the production and marketing of synthetic substances, along with a rigorous demand for more powerful psychotropic effects, are some of the factors that contribute to the increase in a more varied supply, as well as the number of drug users. The development of reliable analytical tools with an on-site response capacity for a preliminary determination contributes significantly to the generation of data for the proper care of situations such as poisoning, the correct application of the country's legislation, and even the provision of objective criteria for the reclassification of the substances. Electrochemical sensors have gained ground in areas of forensic science. The use of specialized technologies to manufacture miniaturized electrodes based on modifications, mainly with nanostructured materials, guides the development of versatile easy-to-handle portable devices that require microquantities of the sample. Likewise, some electrochemical sensors have performance parameters such as detection limits (LOD) up to 0.608 pg/mL, sensitivity and precision that are analytically comparable, under certain conditions, with conventional methodologies coupled with mass detection, which show LOD of the order of magnitude between 10-9 g/mL and 10-12 g/mL for drug determination. This review focuses on the application and comparison of voltammetric electrochemical sensors for the determination of benzylpiperazine (BZP), meta-chlorophenylpiperazine (mCPP), 25B-NBO-Me, dimethyltryptamine (DMT), mephedrone (4-MMC), 4-methylethcathinone (4-MEC) and fentanyl (FYL) representing the emerging drugs available to date on the psychoactive substances market.

A quantidade de novas substâncias psicoativas (NSP) sintéticas aumenta a cada ano no mercado global. A utilização de novas tecnologias de produção e comercialização de substâncias, combinado com uma demanda exigente de efeitos psicotrópicos mais potentes, são alguns dos fatores que contribuem para o aumento de uma oferta mais ampla, assim como a quantidade dos números de consumidores de algum tipo de droga. O desenvolvimento de ferramentas analíticas confiáveis e com uma capacidade de resposta in situ para uma avaliação preliminar, contribuem significativamente para a geração de informações científicas para cuidar casos de envenenamento, aplicar corretamente a lei, e até fornecer dados reais para uma reclassificação mais objetiva de drogas com base em critérios científicos. Sensores eletroquímicos ganharam espaço em áreas da ciência forense. A utilização de tecnologias especializadas para criação de eletrodos miniaturizados com modificações, principalmente com materiais nanoestruturados, norteiam o desenvolvimento de dispositivos portáteis altamente versáteis, de fácil manuseio e que necessitam de microquantidades da amostra. Da mesma forma, alguns sensores eletroquímicos apresentam parâmetros de desempenho -como limites de detecção (LOD) até 0.608 pg/mL, sensibilidade e precisão- que são analiticamente comparáveis, sob certas condições, com metodologias convencionais com detecção de massa -mostram LOD de a ordem de grandeza entre 10-9g/mL e 10-12g/mL para a determinação de determinados medicamentos-. Esta revisão tem como foco a aplicação e comparação analítica de sensores eletro-químicos voltamétricos para determinação de benzilpiperazina (BZP), meta-clorofenilpiperazina (mCPP), 25B-NBOMe, dimetiltriptamina (DMT), mefedrona (4-MMC), 4-metilethcatinona (4-MEC) e fentanilo (FYL), que representam os drogas emergentes disponíveis até o momento no mercado de substâncias psicoativas.

Simulator of Heart Rate and Respiratory Rate for Monitoring Accuracy of Intelligent Sleep Monitoring Devices / 中国医疗器械杂志

OBJECTIVE@#Invent a simulator which provides a simulation of heart rate and respiratory rate to the intelligent sleep monitoring devices based on precision pressure sensors.@*METHODS@#The simulator was composed of control part and simulated silicone doll. The simulated silicone doll contains heartbeat simulator and breathing simulation airbag. Heartbeat and breathing combination pressure signal can be produced according to frequency set values. Frequencies of pressure signal of the simulator were compared with the monitoring results of intelligent sleep monitoring devices with known accuracy to verify the frequency accuracy of pressure signal of the simulator. Verified the repeatability and stability of the simulator with a stopwatch.@*RESULTS@#The heart rate of the simulator was with in ±2 beats per minute of the monitoring results of intelligent sleep monitoring devices and the respiratory rate of the simulator was with in ±2 times per minute of the monitoring results. The repeatability and stability of the simulator was better than ±5% according to results with a stopwatch.@*CONCLUSIONS@#It's practicable to use the simulator which provides a simulation of heart rate and respiratory rate to the accuracy test of the intelligent sleep monitoring devices based on precision pressure sensor.

Proposal of a system for measuring apparent electrical conductivity and moisture of soil for small farmers

In the last 30 years soils decreased 73 % of their productive capacity in the world. One of the main reasons for this decrease has been the politics implemented, as well as the absence of opportunity for the small producer to implement improvement strategies that can increase their productivity in the field. Therefore, in this research a soil measurement system is proposed for small farmers, based on the design of two sensors of low cost: (i) Apparent electrical conductivity (ECa) sensor and (ii) moisture sensor. These measurement variables have the particularity that their characteristics can be associated with the physical properties of the soil for decision-making. The sensors developed in this work employ two techniques: Wenner's method for ECa and electrical impedance measurement to identify the dielectric permittivity associated with the water content of the soil. The system is controlled by the Raspberry Pi 3 board through developed software that allows correlating data with its geolocation. The device was tested in controlled laboratory measurements with calibrated instruments, obtaining a coefficient of . Finally, on-site tests were made to validate their use for small farmers.

Durante los últimos 30 años, los suelos han disminuido un 73 % su capacidad productiva, a nivel mundial. Una de las principales razones para esta cifra a la baja son las políticas implementadas, así como la falta de oportunidad para que el pequeño productor adopte estrategias de mejora, con lo cual, pueda aumentar la productividad. Por lo anterior, en esta investigación, se propone un sistema de medición de suelo para pequeños productores, a partir del diseño de dos sensores de bajo costo: (i) sensor de conductividad eléctrica aparente (CEa) y (ii) sensor de humedad. Estas variables de medición tienen la particularidad que sus características se pueden asociar a las propiedades físicas del suelo, para tomar decisiones. Los sensores desarrollados en este trabajo usan dos técnicas: el método de Wenner, para la CEa y la medición de impedancia eléctrica, para identificar la permitividad dieléctrica asociada con el contenido de agua del suelo. El sistema es controlado mediante la tarjeta Raspberry Pi 3, a través de un software desarrollado, que permite correlacionar los datos con su geolocalización. El dispositivo, se probó en mediciones controladas en laboratorio, con instrumentos calibrados, obteniendo un coeficiente . Finalmente, se hicieron pruebas in situ, con el fin de validar su uso por pequeños agricultores.

ZnO: SnO2 nanocomposite efficacy for gas sensing and microbial applications

The unique characteristics of 2-dimensional hetero structure offers efficient gas sensing with high selectivity to identify gases from the interference gases which is quite difficult. In the present work, ZnO: SnO2Nano composite clusters (NCC) is prepared. A resistive metal oxide volatile organic compound (VOC) gas sensor is fabricated with nullifying the effect of humidity by increasing temperature optimally. A single-step SOL-GEL (SG) synthesis is used to prepare ZnO: SnO2 NCC with maximum Zn/Sn molar concentration ratio of 3. The morphological studies through Scanning Electron Microscopy (SEM), electrical properties due to oxygen vacancies and energy band variations of Nanocomposite are measured. The enhancement of gas sensor sensitivity due to highly mesoporous nature of the composite is observed. From the findings, the abundant mesopores in the range of 2 nm-14 nm and specific surface area of 54.2 m2 g?1 with the average crystal size of 14.236 nm, and polar surface area of the composite 25.9651Åis achieved. When compared to bare ZnO and SnO2 gas sensors, the present gas sensor offers the higher selectivity with enhanced performance due to the mesoporous structure. Fast repeatability rate of 2200 sec at 350?C to ethanol is attained and the overall selectivity of the sensor increased twice as 2.085. The NCC compound is tested firstly with micro organisms such as B. subtilis (B. S), Bacillus cereus (B. C), B. coagulans (B. C), Pseudonymous auriginosa (P. A) are considered for antimicrobial activity. From the findings, zinc stannate compound showed good efficacy towards B. cereus Gram positive and P.A gram-negative. A bacterial growth is arrested highly with B. cereus.

Green electrochemical sensors based on ionic liquid nanocomposites for detection of environmental pollutants

Industrialization and globalization have caused a huge burden on the limited natural resources, which releases various environmental pollutants such as toxic metal ions and pesticides. World Health Organisation (WHO) has set a maximum permissible limit for these toxic pollutants in water, above which, it is unsuitable for drinking purpose. There are various techniques available for the determination of such pollutants like ICP-MS, HPLC, FAAS etc. that are costly, cumbersome, and time consuming. Whereas, electrochemical sensors are portable, fast and can perform multi-analyte sensing. Electrochemical sensor can be made selective by fabricating with nanocomposites having different functional groups. Nowadays, trend of utilizing greener materials in research field is being highly appreciated in accordance with the principles of green chemistry for the application and development of electrochemical sensors. Ionic liquids having non-volatility, low toxicity, wide potential window, high electrochemical stability and conductivity have shown sustainable electrochemical sensing applications. Nanocomposite of these ionic liquids as a sensing platform have been extensively used in electrochemical detection of various pollutants. This work provides a literature survey of different ionic liquid nanocomposite based sensing platform for electrochemical detection of toxic pesticides and heavy metals. They have demonstrated good sensitivity with detection limit below WHO guidelines.

Application of nanocellulose in flexible sensors / 生物医学工程学杂志

The shortage of medical resources promotes medical treatment reform, and smart healthcare is a promising strategy to solve this problem. With the development of Internet, real-time health status is expected to be monitored at home by using flexible healthcare systems, which puts forward new demands on flexible substrates for sensors. Currently, the flexible substrates are mainly traditional petroleum-based polymers, which are not renewable. As a natural polymer, cellulose, owing to its wide range of sources, convenient processing, biodegradability and so on, is an ideal alternative. In this review, the application progress of nanocellulose in flexible sensors is summarized. The structure and the modification methods of cellulose and nanocellulose are introduced at first, and then the application of nanocellulose flexible sensors in real-time medical monitoring is summarized. Finally, the advantages and future challenges of nanocellulose in the field of flexible sensors are discussed.

A descrição teórica da detecção eletroquímica do fármaco olanzapina, assistida pelo compósito do oxihidróxido de cobalto (III) com um corante esquaraínico

Introdução: a olanzapina é um dos fármacos antipsicóticos benzodiazepínicos mais usados no mundo. Apesar da sua eficiência, em concentrações excessivas, ela sói ser tóxica, como quaisquer outros fármacos desta classe. Assim, neste trabalho, se avaliou, pela primeira vez, a possibilidade da detecção eletroquímica do fármaco olanzapina, assistida pelo compósito do oxihidróxido de cobalto (III), emparelhado com o dióxido, com um corante esquaraínico. Método: o modelo matemático trivariante correspondente inclui dois cenários de oxidação do fármaco, possíveis para o caso, incluindo a eletropolimerização indireta da molécula da benzodiazepina condensada, bem como a oxidação do fármaco pelo átomo do enxofre. Este modelo tem sido desenvolvido e analisado mediante a teoria de estabilidade linear e análise de bifurcações. Resultados e discussão: a análise do modelo há mostrado que a hibridez do mecanismo do processo eletroanalítico, aliada à composição e descomposição dos compostos iônicos aquando da sua realização, aumenta a probabilidade da ocorrência do comportamento oscilatório, em relação ao caso mais simples e mais comum. No entretanto, a instabilidade oscilatória se realiza nos valores dos parâmetros, que estão além do limite de detecção. Por sua vez, o estado estacionário se obtém e se mantém facilmente, indicando um processo eletroanalítico eficiente, controlado pela difusão do analito. Conclusões: trata-se de um processo eletroanalítico eficiente, em que o composto de cobalto funciona como substância ativa, e o corante desempenha o papel de mediador

SUMMARY Introduction: olanzapine is one of the most used antipsychotic drugs in the world. Although it is efficient, it may be toxic in excess. Therefore, in this work the possibility of olanzapine electrochemical determination over an electrode, modified by the cobalt (III) oxyhydroxide in pair with its dioxide in a composite with squaraine dye. Methods: the trivariant correspondent mathematical model includes two scenarios of the drug oxidation, possible for the case, including the indirect electropolymerization of the condensed benzodiazepine molecule, like also its oxidation by sulfur atom. This model has been developed and analyzed by means of stability theory and bifurcation analysis. Results and discussion: the analysis of the model has shown that the mechanism hybridity of the electroanalytical process, alongside with the formation and decomposition of ionic compounds during its realization, augments the possibility for the oscillatory behavior realization, relatively to the simplest and commonest case. Nevertheless, the oscillatory instability is realized in parameter values far beyond the detection limit. On the other hand, the stable steady-state is easy to obtain and maintain, indicating an efficient electroanalytical process, controlled by the analyte diffusion. Conclusions: the electroanalytical process is efficient. The cobalt compound is acting as an active substance, and the dye is the mediator.

Introducción: la olanzapina es uno de los fármacos antipsicóticos más utilizados en el mundo. Aunque es eficaz, puede resultar tóxico en exceso. Por tanto, en este trabajo se plantea la posibilidad de la determinación electroquímica de olanzapina sobre un electrodo, modificado por el oxihidróxido de cobalto (III) en pareja con su dióxido en un composito con colorante de escuaraína. Métodos: el modelo matemático correspondiente incluye dos escenarios de oxidación del fármaco, posibles para el caso, que incluyen la electropolimerización indirecta de la molécula de benzodiazepina condensada, así como su oxidación por átomo de azufre. Este modelo ha sido desarrollado y analizado mediante teoría de estabilidad y análisis de bifurcación. Resultados y discusión: el análisis del modelo ha demostrado que el mecanismo de hibridación del proceso electroanalítico, junto con la formación y descomposición de compuestos iónicos durante su realización, aumenta la posibilidad de realización del comportamiento oscilatorio, relativamente al caso más simple y común. Sin embargo, la inestabilidad oscilatoria se realiza en valores de parámetros mucho más allá del límite de detección. Por otro lado, el estado estacionario estable es fácil de obtener y mantener, lo que indica un proceso electroanalítico eficiente, controlado por la difusión del analito. Conclusiones: el proceso electroanalítico es eficiente. El compuesto de cobalto actúa como sustancia activa y el colorante es el mediador.

Uso de sensores inerciales en fisioterapia: Una aproximación a procesos de evaluación del movimiento humano / Use of inertial sensors in physiotherapy: an approach to human movement assessment processes

Resumen Introducción: Los sensores inerciales o unidad de medición inercial (IMU) del inglés Inertial measurement unit, son pequeños dispositivos capaces de medir la aceleración lineal y la velocidad angular, siendo útiles en el área de la salud para la cuantificación y valoración objetiva del movimiento corporal humano. Objetivo: Analizar la información sobre el uso de sensores inerciales como una aproximación a los procesos de evaluación del movimiento corporal humano. Materiales y métodos: Se realizó búsqueda en bases de datos, empleando términos: sensores inerciales, salud, fisioterapia, acelerómetro, actividad física, movimiento y rehabilitación, y sus combinaciones. Como criterios de exclusión se tuvo: artículos exclusivos del campo de ingeniería con información no aplicable a fisioterapia. Resultados: Una IMU es compatible con aplicaciones (APP), con el objetivo de obtener datos de movimiento tridimensionales y como evaluación e intervención, o que permita cuantificar los resultados de la acción motora. Conclusiones: Las IMU tienen amplias posibilidades en áreas afines a la rehabilitación y otras referentes al entrenamiento y el área deportiva; por lo, cual es necesario estandarizar protocolos que permitan la medición de patrones motores que favorezcan los procesos de rehabilitación.

Abstract Introduction: Inertial measurement units (IMU) are small devices capable of measuring linear acceleration and angular velocity. Therefore, they are useful in the health field for the quantification and objective assessment of the human body movement. Objective: To analyze information about the inertial sensors usage, as a way to approach to processes of evaluation of the human body movement. Materials and methods: A database search was performed, using the following terms: inertial sensors, health, physiotherapy, accelerometer physical activity, movement, rehabilitation and their multiple combinations. The exclusion criteria were exclusive articles from the engineering field covering information not relevant for physical therapy. Results: IMUs are devices that are compatible with applications, which can obtain three-dimensional movement data. They can also be used for assessment and intervention to quantify results of motor action. Conclusions: IMUs may have wide applications in fields such as rehabilitation, training and sports. As a result, it is necessary to standardize protocols to measure motor patterns and facilitate rehabilitation processes.

The reproducibility of the 1hz gps in the aciclic displacement with intermittent intensity / La reproducibilidad del gps de 1 hz en desplazamiento acíclico con intensidad intermitente

Objective: the aim of this study was to verify the reproducibility index of the frequency meter with GPS technology with recording speed of 1Hz in acyclic displacement and intermittent intensity, performed by soccer referees. Materials and methods: it was characterized by a field study with a quantitative trait involving 14 men, aged 20.42 ± 2.78 years, from a barracks in the city of Rio de Janeiro. Polar heart rate monitor with 1Hz GPS model V800 was used. The protocol used was adapted from the FIFA test protocol for soccer referees, so that 10 "shots" of 75m in 15s were accomplished by 25m in 20 of recovery. Testing and retest were applied with 7 days interval and identical protocols: heating, ambiance (4 "shots" following the model of the protocol above) and then the test. Since the circuit covered in the test protocol was 1000 m. Results: a mean of 1002.5 ± 17.12 m was obtained in the test and in the test 1010.83 ± 32.88 m, the coefficients of variation were respectively 1% and 3%. The difference was not significant between the test and the retest (P-value> 0.05), and the intraclass correlation coefficient indicated a moderate association between the measures. Conclusion: therefore, it is suggested that it is acceptable to use a frequency gauge with a recording speed of 1Hz to monitor displacements of soccer referees in acyclic displacement and intermittent intensity..Au

Objetivo: el objetivo de este estudio fue verificar el índice de reproducibilidad del medidor de frecuencia con tecnología GPS con velocidad de grabación de 1Hz en desplazamiento acíclico e intensidad intermitente, realizado por árbitros de fútbol. Materiales y métodos: se caracterizó por un estudio de campo con un rasgo cuantitativo que involucró a 14 hombres, de 20.42 ± 2.78 años, de un cuartel en la ciudad de Río de Janeiro. Se utilizó un monitor de frecuencia cardíaca polar con GPS 1Hz modelo V800. El protocolo utilizado fue adaptado del protocolo de prueba de la FIFA para los árbitros de fútbol, de modo que se lograron 10 "tiros" de 75 m en 15 segundos por 25 m en 20 de recuperación. La prueba y la nueva prueba se aplicaron con un intervalo de 7 días y protocolos idénticos: calentamiento, ambiente (4 "disparos" siguiendo el modelo del protocolo anterior) y luego la prueba. Dado que el circuito cubierto en el protocolo de prueba fue de 1000 m. Resultados: se obtuvo una media de 1002.5 ± 17.12 m en la prueba y en la prueba 1010.83 ± 32.88 m, los coeficientes de variación fueron respectivamente 1% y 3%. La diferencia no fue significativa entre la prueba y la nueva prueba (valor P> 0.05), y el coeficiente de correlación intraclase indicó una asociación moderada entre las medidas. Conclusión: por lo tanto, se sugiere que sea aceptable usar un medidor de frecuencia con una velocidad de grabación de 1Hz para monitorear los desplazamientos de los árbitros de fútbol en desplazamiento acíclico e intensidad intermitente..Au

Chemically modified carbon-based electrodes for the determination of paracetamol in drugs and biological samples / 药物分析学报

Paracetamol is a non-steroidal,anti-inflammatory drug widely used in pharmaceutical applications for its sturdy,antipyretic and analgesic action.However,an overdose of paracetamol can cause fulminant hepatic necrosis and other toxic effects.Thus,the development of advantageous analytical tools to detect and determine paracetamol is required.Due to simplicity,higher sensitivity and selectivity as well as costefficiency,electrochemical sensors were fully investigated in last decades.This review describes the advancements made in the development of electrochemical sensors for the paracetamol detection and quantification in pharmaceutical and biological samples.The progress made in electrochemical sensors for the selective detection of paracetamol in the last 10 years was examined,with a special focus on highly innovative features introduced by nanotechnology.As the literature is rather extensive,we tried to simplify this work by summarizing and grouping electrochemical sensors according to the by which manner their substrates were chemically modified and the analytical performances obtained.

Towards wearable and implantable continuous drug monitoring:A review / 药物分析学报

Continuous drug monitoring is a promising alternative to current therapeutic drug monitoring strategies and has a strong potential to reshape our understanding of pharmacokinetic variability and to improve individualised therapy.This review highlights recent advances in biosensing technologies that support continuous drug monitoring in real time.We focus primarily on aptamer-based biosensors,wearable and implantable devices.Emphasis is given to the approaches employed in constructing biosensors.We pay attention to sensors'biocompatibility,calibration performance,long-term characteristics stability and measurement quality.Last,we discuss the current challenges and issues to be addressed in continuous drug monitoring to make it a promising,future tool for individualised therapy.The ongoing efforts are expected to result in fully integrated implantable drug biosensing technology.Thus,we may anticipate an era of advanced healthcare in which wearable and implantable biochips will automatically adjust drug dosing in response to patient health conditions,thus enabling the management of diseases and enhancing individualised therapy.

O estudo teórico do desempenho dos polímeros condutores dos corantes azoicos na detecção eletroquímica de indigo-carmim / The theoretical study of the function of conducting polymers of the azo-dyes in the electrochemical detection of indigo-carmine

RESUMO O desempenho dos polímeros condutores dos corantes azoicos durante a detecção eletroquímica de indigo-carmim foi investigado do ponto de vista teórico, sendo o modelo, correspondente ao caso, descrito e analisado mediante a teoria de estabilidade lineal e da análise de bifiircações. Foi mostrado que o sistema eletroanalítico depende fortemente do pH, pois as concentrações excessivas dos prótons levam à ineficiência eletroanalítica, haja vista o bloqueio dos centros ativos da reação. No entretanto, malgrado o supracitado, os polímeros dos corantes azoicos são modificadores eficientes para determinação do indigo-carmim. A possibilidade das instabilidades oscilatória e monotônica também foi verificada.

SUMMARY The function of the conducting polymers of azo-dyes during the indigo-carmine electrochemical detection has been investigated from the theoretical point of view. The correspondent model has been described and analyzed by means of linear stability theory and bifurcation analysis. It has been shown that the electroanalytical system depends strongly on pH, as the excessive protons concentrations drive the system to the electroanalytical inefficiency, as they block the reaction active sites. Nevertheless, despite of the mentioned, the azo-dyes conducting polymers are efficient modifiers for indigo-carmine electrochemical determination. The possibility of oscillatory and monotonic instabilities has also been verified.

A descrição matemática da detecção eletroquímica dos alcaloides do grupo da insubosina, assistida pelos novos triazóis com e sem composto de ligação / The mathematical description for the electrochemical determination of insubosin alkaloid group, assisted by new triazoles with and without link compound

RESUMO Pela primeira vez, foi feita uma abordagem teórica do desempenho dos novos derivados triazólicos durante a determinação química dos alcaloides acridínicos do grupo insubosina, na presença de uma concentração pequena de um composto de ligação. A detecção eletroanalítica é realizada mediante um mecanismo híbrido, envolvendo ou não a formação de novos compostos iónicos. É possível mostrar que o estado estacionário é estabilzado, apesar de a região topológica, que lhe é correspondente, ser mais estreita que no caso da detecção mais comum. O comportamento oscilatório, neste caso, é mais provável que nos casos mais comuns, mas o fator adicional é relacionado apenas com a introdução de um composto de ligação.

SUMMARY For the first time, a theoretical investigation of novel triazolic derivatives during the chemical determination of acridinic alkaloids of insubosin group in the presence of the presence of the small quantity of the link compound has been realized. The electrochemical determination is realized by a hybrid mechanism, involving or not the formation of novel ionic compounds. It is possible to show that the steady-state is stabilized, despite ofthe narrower correspondent topological region, while compared to the more common detection case. The oscillatory behavior is more probable than in more common cases, due to the introduction of the link compound.

Various Static And Dynamic Balance Measuring And Training Mechanical Tools In Patients With Clinical Conditions: A Literature Review

Background: Balance is defined as the ability to maintain a position within the limits of stability or base of support. It is indicated that postural control system plays an important role in maintenance of balance on the small support base. The complexity of balancing processes makes it challenging to assess balancing abilities in a concise, holistic approach. This study extends previous efforts by reviewing a large number of papers that use of various mechanical tools to assess postural balance and by providing a detailed overview of the common mechanical tools used to assess postural balance and gait. Methods: We searched the electronic database. The literature search produced a total of 302 items. After removal of duplicates, posters, other studies not mention mechanical tools to evaluate static and dynamic balance in clinical conditions, 28 papers met the inclusion criteria for this review. Results: This search selected 7 tools to assess trunk control in various clinical conditions: Inertial balance sensor, Computerised dynamic posturography, Biodex Balance System, Force plate., MatScan® pressure mat, Microsoft Kinect’s built-in RGB-D sensor and Clinical Test of sensory integration using Chinese lantern. Conclusion: Inertial as well as Microsoft Kinect’s built-in RGB-D sensors are cost effective, time effective, does not need a specific set up, analysis static balance as well as the gait parameters. This can therefore be chosen over other mechanical tools due to its better convenience and efficiency.

Human activity recognition based on the inertial information and convolutional neural network / 生物医学工程学杂志

With the rapid improvement of the perception and computing capacity of mobile devices such as smart phones, human activity recognition using mobile devices as the carrier has been a new research hot-spot. The inertial information collected by the acceleration sensor in the smart mobile device is used for human activity recognition. Compared with the common computer vision recognition, it has the following advantages: convenience, low cost, and better reflection of the essence of human motion. Based on the WISDM data set collected by smart phones, the inertial navigation information and the deep learning algorithm-convolutional neural network (CNN) were adopted to build a human activity recognition model in this paper. The K nearest neighbor algorithm (KNN) and the random forest algorithm were compared with the CNN network in the recognition accuracy to evaluate the performance of the CNN network. The classification accuracy of CNN model reached 92.73%, which was much higher than KNN and random forest. Experimental results show that the CNN algorithm model can achieve more accurate human activity recognition and has broad application prospects in predicting and promoting human health.

Nanotechnology for Combating Microbial Contamination of Water

El agua es una necesidad universal que ha sido reportada por las Naciones Unidas (ONU) y la Organización Mundial de la Salud (OMS) como una prioridad. Existe una necesidad apremiante de acceso gratuito al agua potable para las poblaciones de los países en desarrollo. Además, las fuentes de agua de los países desarrollados también requieren atención debido a la presencia de un alto nivel de contaminantes emergentes. Por lo tanto, la nanotecnología parece ser una herramienta poderosa que podría usarse como sensores, filtros, superficies antibacterianas y nanoantimicrobianos. En esta revisión, hemos discutido la aplicación de las nanopartículas y los nanocompuestos para el tratamiento de aguas y aguas residuales. Además, el impacto de las nanopartículas libres como contaminantes emergentes en las plantas de tratamiento de agua, así como en las aguas subterráneas, merece más estudios.

The water is a universal need that has been reported by the United Nations (UN) and World Health Organization (WHO) as a priority. There is a pressing need for free access to drinking water for populations from developing countries. Furthermore, the water sources of developed countries also require attention due to the presence of a high level of emergent contaminants. Therefore, nanotechnology appears to be a powerful tool that could be used as sensors, filters, antibacterial surfaces, and nanoantimicrobials. In this review, we have discussed the application of nanoparticles and nanocomposites for water and wastewater treatment. Moreover, the impact of free-nanoparticles as emergent contaminants in water treatment plants as well as groundwater warrants further studies.

Effects of storage on vis-NIR-SWIR reflectance spectra of Mombasa grass leaf samples / Efeitos do armazenamento no espectro de reflectância vis-NIR-SWIR de amostras foliares de capim Mombaça

ABSTRACT: Vis-NIR-SWIR reflectance spectra of leaf samples, collected in the laboratory, allow the calibration of predictive models to quantify their physicochemical attributes in a practical manner and without producing chemical residues. This technique should enable the development of management strategies for intensification of pasture use. However, spectral analysis performed in the laboratory may be affected by the deterioration of plant material during transport from the field to the lab, so storage methods are necessary. This research aimed to evaluate the effects of different storage methods on the spectral response of Mombasa grass leaves. Three methods were evaluated: (i) artificially refrigerated environment, (ii) humid environment, and (iii) without microenvironment control. These methods were tested in five different storage times: 2 hours, 4 hours, 8 hours, 24 hours and 48 hours. The spectral behavior of the leaves still inserted in the plant was used as a quality reference. Results showed notable changes at the earliest storage time for the treatment without microenvironment control. Both methods with microenvironment control stabilized the occurrence of spectral changes over 48 hours of the samples storage, thus both were suggested for this species.

RESUMO: Espectros de reflectância vis-NIR-SWIR de amostras foliares, coletados em laboratório, permitem a calibração de modelos preditivos para quantificação de seus atributos físico-químicos de maneira prática e sem produção de resíduos químicos. Esta técnica permite o desenvolvimento de estratégias de manejo para a intensificação do uso de pastagens. Contudo, análises espectrais realizadas em laboratório podem ser afetadas pela deterioração do material vegetal durante o transporte do campo ao laboratório, fazendo-se necessário a utilização de métodos de armazenamento. O presente trabalho objetivou avaliar o efeito de diferentes métodos de armazenamento na resposta espectral de folhas de capim Mombaça. Avaliou-se três métodos: (i) ambiente refrigerado artificialmente; (ii) ambiente úmido; e (iii) ao ar livre, sem controle do microambiente; assim como, cinco diferentes tempos de armazenamento: 2 horas, 4 horas, 8 horas, 24 horas e 48 horas. O comportamento espectral das folhas ainda inseridas na planta foi utilizado como referência de qualidade. Os resultados mostraram alterações pronunciadas para o armazenamento ao ar livre já nos primeiros intervalos de tempo. Ambos métodos com controle de microambiente permitiram estabilizar a ocorrência de alterações espectrais ao longo das 48h de armazenamento das amostras, sendo ambos sugeridos para esta espécie.

Use of wearable inertial sensors for the assessment of spatiotemporal gait variables in children: A systematic review

Abstract Aim: The present study aimed to perform a literature review on the use of wearable inertial sensors for gait analysis of children in clinical practice. Methods: Searches were performed in the MEDLINE, EMBASE, Cochrane Library, and PEDro databases for studies involving children or adolescents submitted to gait analysis with the use of wearable inertial sensors. No restrictions were imposed regarding the date of publication or language. Results: Three hundred twenty articles were retrieved, 14 of which met the eligibility criteria and were selected for the present systematic review. Two independent reviewers assessed the risk of bias and study quality using the ROBINS-I and AXIS scale. The studies included in the present review reported multiple outcomes of kinematic gait assessments calculated from the signals provided by the wearable sensors, performed in a hospital setting, outpatient clinic, and a familiar environment, with several types of pediatric conditions. Conclusion: The findings suggest that wearable sensors are effective for the evaluation of quantitative gait variables in children with different pediatric conditions, enabling an objective analysis that should prove useful in the processes of clinical diagnosis and rehabilitation. However, given the relatively small number of studies published on this topic, it is difficult to make strong recommendations regarding the most appropriate equipment, sensor placement, and outcomes for assessing gait in children.

New polypyrrole based bio-sensors for Bio-impedance measurement

Objective: The main task of this work consists in an obtaining polarizable, dry mode, of bio-impedance sensors for non-invasiveECG monitoring, that work without any skin preparation or gel use, in two constructive models, based on conductive organicpolymer polypyrrole and polypyrrole with Ag nanoparticles (NP), as sensitive materials. Methods: The polypyrrole wassynthetized by chemical oxidative polymerization using FeCl3 as oxidant agent. For sensors fabrication two technological variantshave been chosen, a first variant realized by photolithographic method consisting in a substrate of Printed Circuit Board (PCB)with interdigitated copper electrode with step of 0.25 mm and over a distance of 12 mm and two pads. The polypyrrole orpolypyrrole with Ag NP dissolved in ethyl alcohol was deposed on the substrate by dipping method. The second model consists ina polypyrrole powder pressed at a hydraulic press at 10 tones/cm2 of force where one site was deposed a layer of Ag ink forconduction. Results: The performance of bio-impedance sensors were accessed by impedance skin-sensor interface withfrequency in the range of 10 - 300 kHz measurements. The influences of technological fabrication as shape and geometry as wellas the sensitive materials that used, in terms of impedance were analyzed. Conclusions: The introduction of Ag NP in polypyrrole,led to a better behavior, in terms of conduction and impedance response. For all tested sensors, the impedance decreases with thefrequency with a good linearity.

A descrição matemática do processo da detecção eletroquímica do ácido ascórbico sobre o polímero condutor, dopado pelo íon triiodeto / The mathematical description for the process of the electrochemical detection of ascorbic acid over a conducting polymer, doped by a triiodide ion

RESUMO O desempenho do polímero condutor, dopado pelo íon triiodeto, na detecção eletroquímica do ácido ascórbico foi avaliado matematicamente. O modelo matemático, correspondente ao sistema, foi desenvolvido e analisado mediante a teoria de estabilidade linear e de bifurcações. Verificou-se que o polímero condutor pode servir de excelente modificador de elétrodo para a detecção do ácido ascórbico, sendo o triiodeto a substância ativa, e o polímero condutor o mediador. O estado estacionário mantém-se estável facilmente, o que corresponde à vasta zona da linearidade da dependência entre a concentração do fármaco e o parâmetro eletroquímico. A possibilidade das instabilidades oscilatória e monotônica também foi verificada.

SUMMARY The function of the conducting polymer, doped by triiodide ion in the electrochemical determination of the ascorbic acid has been mathematically evaluated. The mathematical model, correspondent to the system, was developed and analyzed by linear stability theory and bifurcation analysis. It was confirmed that the conducting polymer might be an excellent electrode modifier for ascorbic acid determination. The triiodide ion acts as the active substance, and the conducting polymer, as a mediator. The stable steady-state is easy maintain, which is correspondent to the vast zone of the linear dependence between the drug concentration and electrochemical parameter The possibility of oscillatory and monotonic instabilities has also been verified.