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1.
Molecules ; 25(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198195

RESUMO

Wastewater treatment (WWT) is a priority around the world; conventional treatments are not widely used in rural areas owing to the high operating and maintenance costs. In Mexico, for instance, only 40% of wastewater is treated. One sustainable option for WWT is through the use of constructed wetlands (CWs) technology, which may remove pollutants using cells filled with porous material and vegetation that works as a natural filter. Knowing the optimal material and density of plants used per square meter in CWs would allow improving their WWT effect. In this study, the effect of material media (plastic/mineral) and plant density on the removal of organic/inorganic pollutants was evaluated. Low (three plants), medium (six plants) and high (nine plants) densities were compared in a surface area of 0.3 m2 of ornamental plants (Alpinia purpurata, Canna hybrids and Hedychium coronarium) used in polycultures at the mesocosm level of household wetlands, planted on the two different substrates. Regarding the removal of contaminants, no significant differences were found between substrates (p ≥ 0.05), indicating the use of plastic residues (reusable) is an economical option compared to typical mineral materials. However, differences (p = 0.001) in removal of pollutants were found between different plant densities. For both substrates, the high density planted CWs were able to remove COD in a range of 86-90%, PO4-P 22-33%, NH4-N in 84-90%, NO3-N 25-28% and NO2-N 38-42%. At medium density, removals of 79-81%, 26-32, 80-82%, 24-26%, and 39-41%, were observed, whereas in CWs with low density, the detected removals were 65-68%, 20-26%, 79-80%, 24-26% and 31-40%, respectively. These results revealed that higher COD and ammonia were removed at high plant density than at medium or low densities. Other pollutants were removed similarly in all plant densities (22-42%), indicating the necessity of hybrid CWs to increase the elimination of PO4-P, NO3-N and NO2-N. Moreover, high density favored 10 to 20% more the removal of pollutants than other plant densities. In addition, in cells with high density of plants and smaller planting distance, the development of new plant shoots was limited. Thus, it is suggested that the appropriate distance for this type of polyculture plants should be from 40 to 50 cm in expansion to real-scale systems in order to take advantage of the harvesting of species in these and allow species of greater foliage, favoring its growth and new shoots with the appropriate distance to compensate, in the short time, the removal of nutrients.


Assuntos
Plásticos/química , Águas Residuárias , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Biodegradação Ambiental , Conservação dos Recursos Naturais , Poluentes Ambientais , Compostos Inorgânicos , Nitratos , Nitrogênio/análise , Compostos Orgânicos , Oxigênio/química , Plantas , Porosidade , Temperatura , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Zingiberaceae/metabolismo
2.
Sensors (Basel) ; 19(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634587

RESUMO

The current condition of soils is a major area of interest due to the lack of certainty in their physicochemical properties, which can guarantee the quality and the production of a specific crop. Additionally, methodologies to improve land management must be implemented in order to address the consequences of many environmental issues. To date, many techniques have been implemented to improve the accuracy-and more recently the speed-of analysis, in order to obtain results while in the field. Among those, Near Infrared (NIR) spectroscopy has been widely used to achieve the objectives mentioned above. Nevertheless, it requires particular knowledge, and the cost might be high for farmers who own the fields and crops. Thus, the present work uses a system that implements capacitance spectroscopy plus artificial intelligence algorithms to estimate the physicochemical variables of soil used to grow sugar cane. The device uses the frequency response of the soil to determine its magnitude and phase values, which are used by artificial intelligence algorithms that are capable of estimating the soil properties. The obtained results show errors below 8% in the estimation of the variables compared to the analysis results of the soil in laboratories. Additionally, it is a portable system, with low cost, that is easy to use and could be implemented to test other types of soils after evaluating the necessary algorithms or proposing alternatives to restore soil properties.

3.
Sensors (Basel) ; 18(5)2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747374

RESUMO

The evoked potential is a neuronal activity that originates when a stimulus is presented. To achieve its detection, various techniques of brain signal processing can be used. One of the most studied evoked potentials is the P300 brain wave, which usually appears between 300 and 500 ms after the stimulus. Currently, the detection of P300 evoked potentials is of great importance due to its unique properties that allow the development of applications such as spellers, lie detectors, and diagnosis of psychiatric disorders. The present study was developed to demonstrate the usefulness of the Stockwell transform in the process of identifying P300 evoked potentials using a low-cost electroencephalography (EEG) device with only two brain sensors. The acquisition of signals was carried out using the Emotiv EPOC® device—a wireless EEG headset. In the feature extraction, the Stockwell transform was used to obtain time-frequency information. The algorithms of linear discriminant analysis and a support vector machine were used in the classification process. The experiments were carried out with 10 participants; men with an average age of 25.3 years in good health. In general, a good performance (75⁻92%) was obtained in identifying P300 evoked potentials.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados P300/fisiologia , Adulto , Interfaces Cérebro-Computador , Análise Discriminante , Eletrodos , Eletroencefalografia/economia , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte , Tecnologia sem Fio , Adulto Jovem
4.
Rehabil Nurs ; 43(2): 116-124, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29499010

RESUMO

PURPOSE: One of the most important aspects in neuromotor rehabilitation is the need of feedback for patients. The rehabilitation system's efficiency relies on the therapist's judgment; the therapist tells the patient whether he/she is performing the exercises correctly. This process may be quite subjective, because it depends on the therapist's personal opinion. On the other hand, recent studies have shown that vibrotactile biofeedback can improve the effectiveness of interaction as it is a very helpful tool in the physiological process of neuromotor rehabilitation. DESIGN: We designed an interactive system focused on rehabilitation of the upper limbs using active markers and image processing, which consists of drawing activities in both augment and virtual reality. METHODS: The system gives the user a correction through multimodal stimuli feedback (vibrotactile, visual, and sound stimulus) and force measurement to let the patients know if they are not achieving the tasks' goals. FINDINGS: The developed system could be used by nursing assistants to better help patients. The purpose of this system was assisting patients with injuries in shoulders, elbows, or wrists, providing an audio-vibrotactile feedback as a factor of correction in the movements of the patient. To examine our system, 11 participants were asked to participate in an experiment where they performed activities focused to strengthen their fine motor movements. CONCLUSIONS AND CLINICAL RELEVANCE: Results showed show that patients' fine motor skills improved 10% on average by comparing their error rates throughout the sessions.


Assuntos
Terapia Ocupacional/métodos , Enfermagem em Reabilitação/métodos , Realidade Virtual , Adolescente , Adulto , Idoso , Criança , Retroalimentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Terapia Ocupacional/tendências , Enfermagem em Reabilitação/tendências , Extremidade Superior/fisiologia
5.
J Phys Ther Sci ; 28(8): 2293-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27630417

RESUMO

[Purpose] The purposes of this study were to evaluate whether the therapeutic games developed by the study team are significantly effective for upper limb rehabilitation of patients with cerebral palsy and to assess the development of the games and the evolution of patients throughout the therapy sessions. [Subjects and Methods] This study demonstrates the results of using therapeutic games in patients with infantile cerebral palsy. The therapies were performed in 30-minute sessions for about 1 to 4 months. This study shows the progress of five children with cerebral palsy during the sessions. The time it took the children on each road and the times required to complete a task were measured. In addition, the level of difficulty of the games was gradually increased at each session. [Results] Results have shown good progress on the accuracy of the movements and an increase in concentration level during the execution of the games, showing an improvement in the patients' performance by 40-55% faster. [Conclusions] Health games encourage children to comply with therapy. The advantage of the game is that the patient can perform the therapy at home, which could help achieve further progress in patients.

6.
Sensors (Basel) ; 11(1): 612-22, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22346593

RESUMO

There are different schemes based on observers to detect and isolate faults in dynamic processes. In the case of fault diagnosis in instruments (FDI) there are different diagnosis schemes based on the number of observers: the Simplified Observer Scheme (SOS) only requires one observer, uses all the inputs and only one output, detecting faults in one detector; the Dedicated Observer Scheme (DOS), which again uses all the inputs and just one output, but this time there is a bank of observers capable of locating multiple faults in sensors, and the Generalized Observer Scheme (GOS) which involves a reduced bank of observers, where each observer uses all the inputs and m-1 outputs, and allows the localization of unique faults. This work proposes a new scheme named Simplified Interval Observer SIOS-FDI, which does not requires the measurement of any input and just with just one output allows the detection of unique faults in sensors and because it does not require any input, it simplifies in an important way the diagnosis of faults in processes in which it is difficult to measure all the inputs, as in the case of biologic reactors.

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