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Water management in paddy soils can effectively reduce the soil-to-rice grain transfer of either As or Cd, but not of both elements simultaneously due to the higher mobility of As under reducing and Cd under oxidizing soil conditions. Limestone amendment, the common form of liming, is well known for decreasing Cd accumulation in rice grown on acidic soils. Sulfate amendment was suggested to effectively decrease As accumulation in rice, especially under intermittent soil flooding. To study the unknown effects of combined sulfate and limestone amendment under intermittent flooding for simultaneously decreasing As and Cd in rice, we performed a pot experiment using an acidic sandy loam paddy soil. We also included a clay loam paddy soil to study the role of soil texture in low-As rice production under intermittent flooding. We found that liming not only decreased rice Cd concentrations but also greatly decreased dimethylarsenate (DMA) accumulation in rice. We hypothesize that this is due to suppressed sulfate reduction, As methylation, and As thiolation by liming in the sulfate-amended soil and a higher share of deprotonated DMA at higher pH which is taken up less readily than protonated DMA. Decreased gene abundance of potential soil sulfate-reducers by liming further supported our hypothesis. Combined sulfate and limestone amendment to the acidic sandy loam soil produced rice with 43% lower inorganic As, 72% lower DMA, and 68% lower Cd compared to the control soil without amendment. A tradeoff between soil aeration and water availability was observed for the clay loam soil, suggesting difficulties to decrease As in rice while avoiding plant water stress under intermittent flooding in fine-textured soils. Our results suggest that combining sulfate amendment, liming, and intermittent flooding can help to secure rice safety when the presence of both As and Cd in coarse-textured soils is of concern.
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Arsênio , Compostos de Cálcio , Oryza , Óxidos , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Carbonato de Cálcio , Solo , Sulfatos , Argila , Óxidos de Enxofre , Areia , Poluentes do Solo/análiseRESUMO
Inorganic and methylated thioarsenates have recently been reported to form in paddy soil pore waters and accumulate in rice grains. Among them, dimethylmonothioarsenate (DMMTA) is particularly relevant because of its high cytotoxicity and potential misidentification as nonregulated dimethylarsenate (DMA). Studying DMMTA uptake and flag leaf, grain, and husk accumulation in rice plants during grain filling, substantial dethiolation to DMA was observed with only 8.0 ± 0.1, 9.1 ± 0.6, and 1.4 ± 0.2% DMMTA remaining, respectively. More surprisingly, similar shares of DMMTA were observed in control experiments with DMA, indicating in planta DMA thiolation. Exposure of different rice seedling varieties to not only DMA but also to arsenite and monomethylarsenate (MMA) revealed in planta thiolation as a common process in rice. Up to 35 ± 7% DMA thiolation was further observed in the shoots and roots of the model plant Arabidopsis thaliana. Parameters determining the ratio and kinetics of thiolation versus dethiolation are unknown, yet, but less DMA thiolation in glutathione-deficient mutants compared to wild-type plants suggested glutathione concentration as one potential parameter. Our results demonstrate that pore water is not the only source for thioarsenates in rice grains and that especially the currently nonregulated DMA needs to be monitored as a potential precursor of DMMTA formation inside rice plants.
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Arabidopsis , Arsênio , Oryza , Poluentes do Solo , Ácido Cacodílico , GlutationaRESUMO
Accumulation of inorganic arsenic (iAs) and dimethylarsenate (DMA) in rice threatens human health and rice yield, respectively. We studied the yet unclear interactions of soil sulfate amendment and water management for decreasing As accumulation in rice grain in a pot experiment. We show that soil sulfate amendment (+200 mg S/kg soil) decreased grain iAs by 44% without clearly increasing grain DMA under intermittent flooding from booting stage to maturation. Under continuous flooding during this period, sulfate amendment decreased grain iAs only by 25% but increased grain DMA by 68%. The mechanisms of sulfate amendment effects on grain iAs were not explained by porewater composition or in-planta As sequestration but were allocated to the rhizosphere. Grain iAs closely correlated with As in the root iron-plaque (r = 0.92) which was effectively decreased by sulfate amendment and may have acted as an iAs source for rice uptake. Although both sulfate amendment and intermittent flooding substantially increased porewater DMA concentrations, it was the continuous flooding, irrespective of sulfate amendment, that resulted in rice straighthead disease with 47-55% less yield and 258-320% more DMA in grains than intermittent flooding. This study suggests that combining soil sulfate amendment and intermittent flooding can help to secure the quantity and quality of rice produced in As-affected areas. Our results also imply the key role of rhizosphere processes in controlling both iAs and DMA accumulation in rice which should be elucidated in the future.
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Arsênio , Arsenicais , Oryza , Poluentes do Solo , Humanos , Arsênio/análise , Solo , Água , Sulfatos , Poluentes do Solo/análise , Arsenicais/análise , Ácido Cacodílico , Grão Comestível/química , Abastecimento de ÁguaRESUMO
Ría of Huelva, located in southwestern Spain, is a highly metal(loid)-contaminated estuary system where sediments are exceeding action limits in an increasing order for Cd, Zn, Pb, Cu, and As. With a predicted sea level rise over the next 50 years, the estuary will be subject to flooding with brackish water or seawater. To evaluate the risk of metal(loid) mobilization under future climate scenarios, different locations along the estuary were sampled at different depths. Samples were flooded with river water, brackish water, and seawater under different short- and long-term laboratory setups. Potential metal(loid) mobilization showed that water quality standards for As, Pb, Zn, Ni, Cu, and Cd could be exceeded upon seawater flooding. However, metal(loid) mobilization was not predictable solely based on sediment loads. The driving factors for cation and anion mobility were identified to be mainly pH under low salinity and competitive desorption under high salinity conditions. Further drivers such as wave movement or labile C input in C-limited systems were found to enhance metal(loid) mobilization. Long-term flooding of intact sediment cores revealed that sea level rise will have different effects on the estuary system depending on duration of flooding. Short-term flooding in the near future will first affect alkaline sediments and enhance currently low cation mobilization, while anion mobilization due to reductive Fe dissolution will remain high. Once acidic sediments further inland are flooded with seawater, highest contaminant mobilization can be expected as high salinity will further enhance already high cation mobilization under acidic pH. Long-term flooding with seawater will neutralize the sediment pH and limit cation mobilization compared to acidic pH. However, the contaminant load stored in the estuary is so high that, extrapolating data obtained, mobilization could last for >1000 years, e.g. for As, Pb, and Al.
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Hemosuccus pancreaticus is a rare cause of upper gastrointestinal hemorrhage. It is mainly produced by bleeding from a pseudoaneurysm that runs through the pancreatic duct and flows into the second portion of the duodenum. This article presents a case of a patient in the sixth decade of life with upper gastrointestinal bleeding who underwent a computed tomography (CT) scan of the abdomen finding a pseudoaneurysm of the gastroduodenal artery. Subsequently, angiography confirmed active bleeding from the pseudoaneurysm, requiring endovascular treatment by interventional radiology, which was successful with the resolution of the bleeding. In this article, our aim is to expand the information on this pathology and to promote the optimization of diagnostic tests for the timely treatment of this rare disease that is potentially life-threatening.
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Arsenic (As) occurrence in rice is a serious human health threat. Worldwide, regulations typically limit only carcinogenic inorganic As, but not possibly carcinogenic dimethylated oxyarsenate (DMA). However, there is emerging evidence that "DMA", determined by routine acid-based extraction and analysis, hides a substantial share of dimethylated thioarsenates that have similar or higher cytotoxicities than arsenite. Risk assessments characterizing the in vivo toxicity of rice-derived dimethylated thioarsenates are urgently needed. In the meantime, either more sophisticated methods based on enzymatic extraction and separation of dimethylated oxy- and thioarsenates have to become mandatory or total As should be regulated.
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Arsênio , Arsenicais , Oryza , Arsênio/toxicidade , Ácido Cacodílico/toxicidade , Carcinógenos/toxicidade , HumanosRESUMO
Arsenic is one of the most relevant environmental pollutants and human health threats. Several arsenic species occur in soil pore waters. Recently, it was discovered that these include inorganic and organic thioarsenates. Among the latter, dimethylmonothioarsenate (DMMTA) is of particular concern because in mammalian cells, its toxicity was found to exceed even that of arsenite. We investigated DMMTA toxicity for plants in experiments with Arabidopsis thaliana and indeed observed stronger growth inhibition than with arsenite. DMMTA caused a specific, localized deformation of root epidermal cells. Toxicity mechanisms apparently differ from those of arsenite since no accumulation of reactive oxygen species was observed in DMMTA-exposed root tips. Also, there was no contribution of the phytochelatin pathway to the DMMTA detoxification as indicated by exposure experiments with respective mutants and thiol profiling. RNA-seq analysis found strong transcriptome changes dominated by stress-responsive genes. DMMTA was taken up more efficiently than the methylated oxyarsenate dimethylarsenate and highly mobile within plants as revealed by speciation analysis. Shoots showed clear indications of DMMTA toxicity such as anthocyanin accumulation and a decrease in chlorophyll and carotenoid levels. The toxicity and efficient translocation of DMMTA within plants raise important food safety issues.
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Arabidopsis , Arsênio , Arsenitos , Arabidopsis/genética , Arabidopsis/metabolismo , Arsênio/metabolismo , Arsênio/toxicidade , Ácido Cacodílico , Humanos , Fitoquelatinas , Plantas/metabolismoRESUMO
INTRODUCTION: ST segment elevation myocardial infarction is a common reason for out-of-hospital cardiac arrest in adult patients. The surveillance of the ST segment in the electrocardiogram is limited to visual presentation. However, the ST segment can change during the course of treatment. If ST elevation is present immediate coronary revascularization is needed, therefore detecting ST elevation changes the treatment fundamentally. Sonification of the ST segment is a new method which enables the emergency team to detect intermediate changes of the ST segment. MATERIAL AND METHODS: We have chosen two sonification designs which were introduced to two groups, medical students and computer science students. Twenty-one participants took part in the study. The sonification was designed for evaluation of the ST segment. The user was supposed to become empowered to distinguish between no, medium-low, medium-high or extreme ST elevation by listening to the sonification. The two groups were asked to evaluate the sounds for possible ST elevation as well as for aesthetics and usability. In a second study twenty-five medical students were taking part in a medical scenario in which sonification was played during a simulated case. The patient was suffering from a myocardial infarction, ST elevation was transient and sonification sounds were changing appropriately. The students were supposed to detect these changes and act accordingly by modifying the treatment. RESULTS: Both groups were able to classify ST segment elevation by listening to the sonification samples. The higher the ST segment, the better was the detection rate overall. In all of the three categories (pleasantness, informativeness and long-term listening) the Water Ambience sonification was rated higher compared to the Polarity sonification. Moreover, in the two groups that took part in the study, we found a significant difference when comparing classification performance using both sonification designs. For the group of medical students as t(20) = 4.31, p = 3.44 × 10-4, p < 0.01 and for the computer science students as t(19) = 3.40, p = 9.39 × 10-6, p < 0.01. In the simulated medical scenario participants indicated that 96% detected the ST elevation. 60% stated that sonification played a role whereas for 32% it did not play a role for the detection of ST elevation. CONCLUSIONS: Sonification has the potential to play an important role as a new supporting tool for the surveillance of the ST segment during the care of patients with suspicion of myocardial infarction. It can be helpful to differentiate between ST segment elevation myocardial infarction and non-ST segment myocardial infarction especially if ST elevation is transient. Furthermore, sonification is viewed as pleasant to listen to and might not contribute to alarm fatigue.
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Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Adulto , Eletrocardiografia/métodos , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnósticoRESUMO
The relevance of the human oral microbiome to our understanding of human health has grown in recent years as microbiome studies continue to develop. Given the links of the oral cavity with the digestive, respiratory and circulatory systems, the composition of the oral microbiome is relevant beyond just oral health, impacting systemic processes across the body. However, we still have a very limited understanding about intrinsic and extrinsic factors that shape the composition of the healthy oral microbiome. Here, we followed a citizen-science approach to assess the relative impact on the oral microbiome of selected biological, social, and lifestyle factors in 1648 Spanish individuals. We found that the oral microbiome changes across age, with middle ages showing a more homogeneous composition, and older ages showing more diverse microbiomes with increased representation of typically low abundance taxa. By measuring differences within and between groups of individuals sharing a given parameter, we were able to assess the relative impact of different factors in driving specific microbial compositions. Chronic health disorders present in the analyzed population were the most impactful factors, followed by smoking and the presence of yeasts in the oral cavity. Finally, we corroborate findings in the literature that relatives tend to have more similar oral microbiomes, and show for the first time a similar effect for classmates. Multiple intrinsic and extrinsic factors jointly shape the oral microbiome. Comparative analysis of metabarcoding data from a large sample set allows us to disentangle the individual effects.
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Bactérias , Microbiota , Bactérias/genética , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Boca , EspanhaRESUMO
Introduction: Cystic fibrosis (CF) is an autosomal genetic disease, associated with the production of excessively thick mucosa and with life-threatening chronic lung infections. The microbiota of the oral cavity can act as a reservoir or as a barrier for infectious microorganisms that can colonize the lungs. However, the specific composition of the oral microbiome in CF is poorly understood.Methods: In collaboration with CF associations in Spain, we collected oral rinse samples from 31 CF persons (age range 7-47) and matched controls, and then performed 16S rRNA metabarcoding and high-throughput sequencing, combined with culture and proteomics-based identification of fungi to survey the bacterial and fungal oral microbiome.Results: We found that CF is associated with less diverse oral microbiomes, which were characterized by higher prevalence of Candida albicans and differential abundances of a number of bacterial taxa that have implications in both the connection to lung infections in CF, as well as potential oral health concerns, particularly periodontitis and dental caries.Conclusion: Overall, our study provides a first global snapshot of the oral microbiome in CF. Future studies are required to establish the relationships between the composition of the oral and lung microbiomes in CF.
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Interpersonal rehabilitation games, compared to single-player games, enhance motivation and intensity level. Usually, it is complicated to restrict the use of the system to pairs of impaired patients who have a similar skill level. Thus, such games must be dynamically adapted. Difficulty-adaptation algorithms are usually based only on performance parameters. In this way, the patient's condition cannot be considered when adapting the game. Introducing physiological reactions could help to improve decision-making. However, it is difficult to control how social interaction influences physiological reactions, making it difficult to interpret physiological responses. This article aimed to explore the changes in physiological responses due to the social interaction of a competitive game modality. This pilot study involved ten unimpaired participants (five pairs). We defined different therapy sessions: (i) a session without a competitor; (ii) two sessions with a virtual competitor with different difficulty levels; (iii) a competitive game. Results showed a difference in the physiological response in the competitive mode concerning single-player mode only due to the interpersonal game modality. In addition, feedback from participants suggested that it was necessary to keep a certain difficulty level to make the activity more challenging, and therefore be more engaging and rewarding.
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Reabilitação do Acidente Vascular Cerebral , Jogos de Vídeo , Terapia por Exercício , Humanos , Motivação , Projetos PilotoRESUMO
Inorganic and methylated thioarsenates have recently been reported to contribute substantially to arsenic (As) speciation in paddy-soil pore waters. Here, we show that thioarsenates can also accumulate in rice grains and rice products. For their detection, a method was developed using a pepsin-pancreatin enzymatic extraction followed by chromatographic separation at pH 13. From 54 analyzed commercial samples, including white, parboiled and husked rice, puffed rice cakes, and rice flakes, 50 contained dimethylmonothioarsenate (DMMTA) (maximum 25.6 µg kg-1), 18 monothioarsenate (MTA) (maximum 5.6 µg kg-1), 14 dimethyldithioarsenate (DMDTA) (maximum 2.8 µg kg-1), and 5 dithioarsenate (DTA) (maximum 2.3 µg kg-1). Additionally, we show that the commonly used nitric acid extraction transforms MTA to arsenite and DMMTA and DMDTA to dimethylarsenate (DMA). Current food guidelines do not require an analysis of thioarsenates in rice and only limit the contents of inorganic oxyarsenic species (including acid-extraction-transformed MTA), but not DMA (including acid-extraction-transformed DMMTA and DMDTA).
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Arsênio , Oryza , Ácido Cacodílico , Estruturas Vegetais , SoloRESUMO
The diverse benefits of synthetic polymers is overshadowed by the amount of plastic waste and its whereabouts. The problem can only be tackled by reducing and recycling of plastics. In this respect, investigating the (microbial) degradation of each type of polymer currently used may provide further understanding that fosters the development of new feasible recycling technologies. Here, we present a strategy to isolate bacteria from environmental samples that are able to degrade hydrolysis products and building blocks of polyurethane (PUR). Protocols are presented to enrich bacteria on the primary diamines 2,4-diaminotoluene (TDA) and 4,4'-diaminodiphenylmethane (MDA) as well as an oligomeric PUR (Sigma Aldrich, proprietary composition). For TDA and the oligomeric PUR, methods are suggested to monitor their concentration in bacterial enrichment cultures.
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Plásticos , Poliuretanos , Bactérias , Biodegradação Ambiental , ReciclagemRESUMO
The fate of plastic waste and a sustainable use of synthetic polymers is one of the major challenges of the twenty first century. Waste valorization strategies can contribute to the solution of this problem. Besides chemical recycling, biological degradation could be a promising tool. Among the high diversity of synthetic polymers, polyurethanes are widely used as foams and insulation materials. In order to examine bacterial biodegradability of polyurethanes, a soil bacterium was isolated from a site rich in brittle plastic waste. The strain, identified as Pseudomonas sp. by 16S rRNA gene sequencing and membrane fatty acid profile, was able to grow on a PU-diol solution, a polyurethane oligomer, as the sole source of carbon and energy. In addition, the strain was able to use 2,4-diaminotoluene, a common precursor and putative degradation intermediate of polyurethanes, respectively, as sole source of energy, carbon, and nitrogen. Whole genome sequencing of the strain revealed the presence of numerus catabolic genes for aromatic compounds. Growth on potential intermediates of 2,4-diaminotoluene degradation, other aromatic growth substrates and a comparison with a protein data base of oxygenases present in the genome, led to the proposal of a degradation pathway.
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Introduction: The oral cavity harbors an abundant and diverse microbial community (i.e. the microbiome), whose composition and roles in health and disease have been the focus of intense research. Down syndrome (DS) is associated with particular characteristics in the oral cavity, and with a lower incidence of caries and higher incidence of periodontitis and gingivitis compared to control populations. However, the overall composition of the oral microbiome in DS and how it varies with diverse factors like host age or the pH within the mouth are still poorly understood. Methods: Using a Citizen-Science approach in collaboration with DS associations in Spain, we performed 16S rRNA metabarcoding and high-throughput sequencing, combined with culture and proteomics-based identification of fungi to survey the bacterial and fungal oral microbiome in 27 DS persons (age range 7-55) and control samples matched by geographical distribution, age range, and gender. Results: We found that DS is associated with low salivary pH and less diverse oral microbiomes, which were characterized by lower levels of Alloprevotella, Atopobium, Candidatus Saccharimonas, and higher amounts of Kingella, Staphylococcus, Gemella, Cardiobacterium, Rothia, Actinobacillus, and greater prevalence of Candida. Conclusion: Altogether, our study provides a first global snapshot of the oral microbiome in DS. Future studies are required to establish whether the observed differences are related to differential pathology in the oral cavity in DS.
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Antibiotic resistance is an emerging worldwide concern with serious repercussions in terms of morbi-mortality. Bearing in mind that the inadequate use of antibiotics, by healthcare staff as well as by the general population, is one of its main causes, a multidisciplinary approach is required to try to combat it. The aim of the present study was to determine nursing students' knowledge and awareness of antibiotic use, resistance and stewardship. A cross-sectional design was used. A total of 578 nursing students from the University of Santiago de Compostela (Spain), ≥18 years old of both sexes were invited to complete the Spanish version of the questionnaire "Knowledge and awareness of the use, resistance and administration of antibiotics" between February and April 2019. Students had a low level of knowledge about antibiotics, 4.1 (CI95% = 3.4-4.8), especially in relation to antibiotic resistance. As the students were aware of this deficiency, the majority affirmed (>90%) that the current curriculum of nursing degree should have more training on antibiotics and infection control. Nursing staff play an important role in the rational use of antibiotics and as teachers of patients, so their training could be key in fighting antibiotic resistance.
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In this paper, the analysis of the intensity of muscle activations in different subjects when they perform an industrial task in a repetitive way assisted by a robotic upper-limb exoskeleton is presented. To do that, surface electromyography (EMG) signals were monitored with and without a robotic upper-limb exoskeleton for 10 subjects during a drilling task, a typical tedious maintenance or industrial task. Our results show that wearing the upper-limb exoskeleton substantially reduces muscle activity during a drilling task above head height. Specifically, there is statistically significant differences in the pectoralis major and rhomboids muscles between the groups wearing or not wearing the robotic upper-limb exoskeleton.
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Braço/fisiologia , Eletromiografia/métodos , Adulto , Fenômenos Biomecânicos , Eletromiografia/instrumentação , Desenho de Equipamento , Exoesqueleto Energizado , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Impressão Tridimensional , Adulto JovemRESUMO
Methylated and inorganic thioarsenates have recently been reported from paddy fields besides the better-known oxyarsenates. Methylated thioarsenates are highly toxic for humans, yet their uptake, transformation, and translocation in rice plants is unknown. Here, hydroponic experiments with 20 day old rice plants showed that monomethylmonothioarsenate (MMMTA), dimethylmonothioarsenate (DMMTA), and monothioarsenate (MTA) were taken up by rice roots and could be detected in the xylem. Total arsenic (As) translocation from roots to shoots was higher for plants exposed to DMMTA, MTA, and dimethylarsenate (DMAV) compared to MMMTA and monomethylarsenate (MMAV). All thioarsenates were partially transformed in the presence of rice roots, but processes and extents differed. MMMTA was subject to abiotic oxidation and largely dethiolated to MMAV already outside the plant, probably due to root oxygen loss. DMMTA and MTA were not oxidized abiotically. Crude protein extracts showed rapid enzymatic reduction for MTA but not for DMMTA. Our study implies that DMMTA has the highest potential to contribute to total As accumulation in grains either as DMAV or partially as DMMTA. DMMTA has once been detected in rice grains using enzymatic extraction. By routine acid extraction, DMMTA is determined as DMAV and thus escapes regulation despite its toxicity.
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Arsênio , Arsenicais , Oryza , Transporte Biológico , Ácido Cacodílico , HumanosRESUMO
This study aims to explore the relationship between the stress level and the exercise intensity performing a rehabilitation task, aided by an upper limb rehabilitation robot, in a game in single-player mode and competitive mode. The stress level has been estimated by means of the Galvanic Skin Response(GSR). The results prove that to employ a social game mode like the competitive one, makes possible to increase the intensity level increasing the stress level to a lesser extent than in single-player modes.
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Braço , Terapia por Exercício , Humanos , Medicina , Reabilitação do Acidente Vascular Cerebral , Extremidade Superior , Jogos de VídeoRESUMO
This paper presents the development of an optical force sensor architecture directed to prototyping and cost-effective applications, where the actual force requirements are still not well defined or the most suitable commercial technologies would highly increase the cost of the device. The working principle of this sensor consists of determining the displacement of a lens by measuring the distortion of a refracted light beam. This lens is attached to an elastic interface whose elastic constant is known, allowing the estimation of the force that disturbs the optical system. In order to satisfy the requirements of the design process in an inexpensive way, this sensor can be built by fast prototyping technologies and using non-optical grade elements. To deal with the imperfections of this kind of manufacturing procedures and materials, four fitting models are proposed to calibrate the implemented sensor. In order to validate the system, two different sensor implementations with measurement ranges of ±45 N and ±10 N are tested with the proposed models, comparing the resulting force estimation with respect to an industrial-grade load cell. Results show that all models can estimate the loads with an error of about 6% of the measurement range.