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1.
Sensors (Basel) ; 24(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38203079

RESUMO

Particle detector systems require data acquisition systems (DAQs) as their back-end. This paper presents a new edge-computing DAQ that is capable of handling multiple pixel detectors simultaneously and was designed for particle-tracking experiments. The system was designed for the ROC4SENS readout chip, but its control logic can be adapted for other pixel detectors. The DAQ was based on a system-on-chip FPGA (SoC FPGA), which includes an embedded microprocessor running a fully functional Linux system. An application using a client-server architecture was developed to facilitate remote control and data visualization. The comprehensive DAQ is very compact, thus reducing the typical hardware load in particle tracking experiments, especially during the obligatory characterization of particle telescopes.

2.
Sensors (Basel) ; 23(24)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38139579

RESUMO

A significant proportion of the world's agricultural production is lost to pests and diseases. To mitigate this problem, an AIoT system for the early detection of pest and disease risks in crops is proposed. It presents a system based on low-power and low-cost sensor nodes that collect environmental data and transmit it once a day to a server via a NB-IoT network. In addition, the sensor nodes use individual, retrainable and updatable machine learning algorithms to assess the risk level in the crop every 30 min. If a risk is detected, environmental data and the risk level are immediately sent. Additionally, the system enables two types of notification: email and flashing LED, providing online and offline risk notifications. As a result, the system was deployed in a real-world environment and the power consumption of the sensor nodes was characterized, validating their longevity and the correct functioning of the risk detection algorithms. This allows the farmer to know the status of their crop and to take early action to address these threats.


Assuntos
Agricultura , Algoritmos , Produtos Agrícolas , Comportamentos Relacionados com a Saúde , Longevidade
3.
J Environ Manage ; 338: 117831, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37023609

RESUMO

Governments worldwide are increasingly concerned about ensuring a balance between economic and environmental well being. Global economies, particularly developing ones, emphasize the importance of achieving escofriendly growth to maintain the levels of the ecological footprint while achieving higher economic growth. The ecological footprint is a comprehensive indicator of environmental degradation. It is used to assess the state of the environment because it reflects the impact of all human activities on nature. This study contributes to the literature by offering a novel analytical approach for solving complex interactions of ecological footprint antecedents, advancing the theoretical reasoning behind how government policy combines to explain the ecological footprint from some G7 countries (France, Italy, Japan, United Kingdom, and Germany) from 1996 to 2020. To establish a composite score of environmental footprint, we used complexity theory as well as fuzzy set qualitative comparative analysis (fsQCA) and necessary condition analysis (NCA). Our analysis revealed that low expenditures on environmental protection and waste management, low taxes on transport, and high energy use are sufficient conditions to be included in the causal configurations for a high ecological footprint. Additionally, the sufficient solution, which has the highest coverage score that produces a low ecological footprint relies on high expenditure on environmental protection and high taxes on transportation. In this framework, Japan, Italy, and France have more effective government policies in terms of reducing the ecological footprint.


Assuntos
Dióxido de Carbono , Mudança Climática , Humanos , Dióxido de Carbono/análise , Conservação dos Recursos Naturais , Desenvolvimento Econômico , França
4.
Sensors (Basel) ; 22(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35591177

RESUMO

Current interest in Fourier lightfield microscopy is increasing, due to its ability to acquire 3D images of thick dynamic samples. This technique is based on simultaneously capturing, in a single shot, and with a monocular setup, a number of orthographic perspective views of 3D microscopic samples. An essential feature of Fourier lightfield microscopy is that the number of acquired views is low, due to the trade-off relationship existing between the number of views and their corresponding lateral resolution. Therefore, it is important to have a tool for the generation of a high number of synthesized view images, without compromising their lateral resolution. In this context we investigate here the use of a neural radiance field view synthesis method, originally developed for its use with macroscopic scenes acquired with a moving (or an array of static) digital camera(s), for its application to the images acquired with a Fourier lightfield microscope. The results obtained and presented in this paper are analyzed in terms of lateral resolution and of continuous and realistic parallax. We show that, in terms of these requirements, the proposed technique works efficiently in the case of the epi-illumination microscopy mode.


Assuntos
Imageamento Tridimensional , Microscopia , Imageamento Tridimensional/métodos , Aprendizado de Máquina , Microscopia/métodos
5.
Microsc Microanal ; 26(6): 1158-1167, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33168124

RESUMO

Phytoliths can be an important source of information related to environmental and climatic change, as well as to ancient plant use by humans, particularly within the disciplines of paleoecology and archaeology. Currently, phytolith identification and categorization is performed manually by researchers, a time-consuming task liable to misclassifications. The automated classification of phytoliths would allow the standardization of identification processes, avoiding possible biases related to the classification capability of researchers. This paper presents a comparative analysis of six classification methods, using digitized microscopic images to examine the efficacy of different quantitative approaches for characterizing phytoliths. A comprehensive experiment performed on images of 429 phytoliths demonstrated that the automatic phytolith classification is a promising area of research that will help researchers to invest time more efficiently and improve their recognition accuracy rate.


Assuntos
Arqueologia , Plantas , Humanos
6.
J Sport Rehabil ; 29(8): 1222-1227, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32188790

RESUMO

CONTEXT: Infrared thermography has been used to detect skeletal muscle overload and fatigue in athletes, but its use in injury prevention in professional soccer has not been studied to date. OBJECTIVES: To establish a novel injury prevention program based on infrared thermography and to determine its influence on the injury incidence in professional soccer players in the preseason. DESIGN: A cross-sectional, prospective study design was used to compare a conventional injury prevention program (CPP) applied over the first preseason and an infrared thermography injury prevention program (IRTPP) carried out in the following preseason. SETTING: Soccer training ground. PARTICIPANTS: Twenty-four players belonging to a first division soccer team from Spain. MAIN OUTCOME MEASURES: Injury incidences of each player were recorded according to the Orchard Sports Injury Classification System (version 10.0) convention to determine the injury classification, location, and type. RESULTS: The incidence of injuries decreased from 15 injuries in the CPP preseason (0.63 [0.77] injuries per player) to 6 injuries in the second preseason when the IRTPP was applied (0.25 [0.53] injuries per player). The days of absence due to injuries also decreased from the CPP preseason (156 d, 10.4 [11.0] d per injury) to the IRTPP preseason (14 d, 2.3 [2.8] d per injury). The injury severity also decreased from the first preseason to the second preseason, and fewer musculoskeletal injuries in the thigh, hip, and groin were reported. CONCLUSIONS: The implementation of an IRTPP can reduce the presence of injuries by identifying players potentially at risk and as a result, reducing the injury severity and days lost as a consequence.


Assuntos
Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/prevenção & controle , Futebol/lesões , Termografia/métodos , Adulto , Traumatismos em Atletas/terapia , Terapia Combinada , Estudos Transversais , Humanos , Incidência , Masculino , Modalidades de Fisioterapia , Estudos Prospectivos , Adulto Jovem
7.
Opt Express ; 26(12): 15623-15631, 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-30114820

RESUMO

We propose a method to perform color imaging with a single photodiode by using light structured illumination generated with a low-cost color LED array. The LED array is used to generate a sequence of color Hadamard patterns which are projected onto the object by a simple optical system while the photodiode records the light intensity. A field programmable gate array (FPGA) controls the LED panel allowing us to obtain high refresh rates up to 10 kHz. The system is extended to 3D imaging by simply adding a low number of photodiodes at different locations. The 3D shape of the object is obtained by using a non-calibrated photometric stereo technique. Experimental results are provided for an LED array with 32 × 32 elements.

8.
J Opt Soc Am A Opt Image Sci Vis ; 34(10): 1776-1786, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036047

RESUMO

In this work, a 3D reconstruction approach for flexible sensing inspired by integral imaging techniques is proposed. This method allows the application of different integral imaging techniques, such as generating a depth map or the reconstruction of images on a certain 3D plane of the scene that were taken with a set of cameras located at unknown and arbitrary positions and orientations. By means of a photo-consistency measure proposed in this work, all-in-focus images can also be generated by projecting the points of the 3D plane into the sensor planes of the cameras and thereby capturing the associated RGB values. The proposed method obtains consistent results in real scenes with different surfaces of objects as well as changes in texture and lighting.

9.
Proc Natl Acad Sci U S A ; 110(3): E185-92, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23213258

RESUMO

A strong positive correlation between vegetation canopy bidirectional reflectance factor (BRF) in the near infrared (NIR) spectral region and foliar mass-based nitrogen concentration (%N) has been reported in some temperate and boreal forests. This relationship, if true, would indicate an additional role for nitrogen in the climate system via its influence on surface albedo and may offer a simple approach for monitoring foliar nitrogen using satellite data. We report, however, that the previously reported correlation is an artifact--it is a consequence of variations in canopy structure, rather than of %N. The data underlying this relationship were collected at sites with varying proportions of foliar nitrogen-poor needleleaf and nitrogen-rich broadleaf species, whose canopy structure differs considerably. When the BRF data are corrected for canopy-structure effects, the residual reflectance variations are negatively related to %N at all wavelengths in the interval 423-855 nm. This suggests that the observed positive correlation between BRF and %N conveys no information about %N. We find that to infer leaf biochemical constituents, e.g., N content, from remotely sensed data, BRF spectra in the interval 710-790 nm provide critical information for correction of structural influences. Our analysis also suggests that surface characteristics of leaves impact remote sensing of its internal constituents. This further decreases the ability to remotely sense canopy foliar nitrogen. Finally, the analysis presented here is generic to the problem of remote sensing of leaf-tissue constituents and is therefore not a specific critique of articles espousing remote sensing of foliar %N.


Assuntos
Nitrogênio/análise , Tecnologia de Sensoriamento Remoto/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Árvores/química , Ciclo do Carbono , Clima , Interpretação Estatística de Dados , Ecossistema , Luz , Ciclo do Nitrogênio , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espalhamento de Radiação , Árvores/metabolismo , Árvores/efeitos da radiação
10.
Opt Lett ; 40(2): 135-8, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25679827

RESUMO

Phase-encoded nanostructures such as quick response (QR) codes made of metallic nanoparticles are suggested to be used in security and authentication applications. We present a polarimetric optical method able to authenticate random phase-encoded QR codes. The system is illuminated using polarized light, and the QR code is encoded using a phase-only random mask. Using classification algorithms, it is possible to validate the QR code from the examination of the polarimetric signature of the speckle pattern. We used Kolmogorov-Smirnov statistical test and Support Vector Machine algorithms to authenticate the phase-encoded QR codes using polarimetric signatures.

11.
Anal Bioanal Chem ; 407(25): 7747-56, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26255297

RESUMO

Using Raman and infrared spectroscopy, we monitored spectral changes occurring in the blood plasma of patients with Alzheimer's disease (AD) in relation to healthy controls. The protein secondary structure as reflected by amide I band involves ß-sheet enrichment, which may be attributable to Aß peptide formation and to increasing proportion of the globulins that are ß-sheet rich. Likewise, the behavior of the infrared 1200-1000-cm(-1) region and the Raman 980-910- and 450-400-cm(-1) regions can be explained in terms of the said plasma composition change. Further, the 744-cm(-1) Raman band from healthy control plasma shows frequency upshifting in the course of AD, which may be generated by the platelets collected in blood plasma. Linear discrimination analysis and receiver operating characteristic (ROC) analysis have been used to distinguish between patients with AD and age-matched healthy controls with a diagnostic accuracy of about 94%.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Proteínas Sanguíneas/química , Análise Discriminante , Humanos , Plasma/química , Estrutura Secundária de Proteína , Curva ROC , Sensibilidade e Especificidade , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos
12.
J Opt Soc Am A Opt Image Sci Vis ; 31(10): 2312-20, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25401260

RESUMO

Three-dimensional (3D) integral imaging allows one to reconstruct a 3D scene, including range information, and provides sectional refocused imaging of 3D objects at different ranges. This paper explores the potential use of 3D passive sensing integral imaging for human gesture recognition tasks from sequences of reconstructed 3D video scenes. As a preliminary testbed, the 3D integral imaging sensing is implemented using an array of cameras with the appropriate algorithms for 3D scene reconstruction. Recognition experiments are performed by acquiring 3D video scenes of multiple hand gestures performed by ten people. We analyze the capability and performance of gesture recognition using 3D integral imaging representations at given distances and compare its performance with the use of standard two-dimensional (2D) single-camera videos. To the best of our knowledge, this is the first report on using 3D integral imaging for human gesture recognition.


Assuntos
Gestos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Humanos
13.
J Sports Sci ; 32(13): 1263-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24787731

RESUMO

The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.


Assuntos
Extremidade Inferior/lesões , Futebol/lesões , Adulto , Comportamento Competitivo , Transtornos Traumáticos Cumulativos/epidemiologia , Humanos , Incidência , Masculino , Músculo Esquelético/lesões , Educação Física e Treinamento , Estudos Prospectivos , Recidiva , Espanha/epidemiologia , Entorses e Distensões/epidemiologia , Traumatismos dos Tendões/epidemiologia , Adulto Jovem
14.
Opt Express ; 20(23): 25960-9, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23187411

RESUMO

This paper presents an acquisition system and a procedure to capture 3D scenes in different spectral bands. The acquisition system is formed by a monochrome camera, and a Liquid Crystal Tunable Filter (LCTF) that allows to acquire images at different spectral bands in the [480, 680]nm wavelength interval. The Synthetic Aperture Integral Imaging acquisition technique is used to obtain the elemental images for each wavelength. These elemental images are used to computationally obtain the reconstruction planes of the 3D scene at different depth planes. The 3D profile of the acquired scene is also obtained using a minimization of the variance of the contribution of the elemental images at each image pixel. Experimental results show the viability to recover the 3D multispectral information of the scene. Integration of 3D and multispectral information could have important benefits in different areas, including skin cancer detection, remote sensing and pattern recognition, among others.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Cristais Líquidos , Óptica e Fotônica , Algoritmos , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/métodos , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/métodos , Luz , Melanoma/diagnóstico , Modelos Estatísticos , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes , Neoplasias Cutâneas/diagnóstico
15.
Anal Bioanal Chem ; 402(6): 2015-21, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22271100

RESUMO

Peripheral mononuclear leukocytes from Alzheimer's disease (AD) patients were analyzed by infrared spectroscopy and their spectroscopic properties were compared with those from age-matched healthy controls. Two-dimensional correlation analysis of mean spectra measured at various disease stages shows that the protein secondary structure from AD patients involves ß-sheet enrichment and carbonyl intensity increase relative to healthy controls. The area percentages of ß-sheets, which were obtained by using a peak ratio second-derivative spectral treatment, were used for receiver operating characteristic (ROC) analysis to distinguish between patients with AD and age-matched healthy controls. The critical concentration and area under the curve (AUC) were determined by this curve analysis which showed a good performance for this quantitative assay. The results were 90% sensitivity and 90.5% specificity for determinations involving mild and moderate AD patients, and 82.1% sensitivity and 90.5% specificity for determinations involving patients at the three AD stages (mild, moderate, and severe). The AUC was greater than 0.85 in both scenarios. Taken together these results show that healthy controls are distinguished from mild and moderate AD patients better than from patients with severe disease and suggest that this infrared analysis is a promising strategy for AD diagnostics.


Assuntos
Doença de Alzheimer/metabolismo , Leucócitos Mononucleares/química , Proteínas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Doença de Alzheimer/diagnóstico , Área Sob a Curva , Feminino , Humanos , Masculino , Estrutura Secundária de Proteína
18.
Biochemistry ; 49(23): 4724-31, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20469947

RESUMO

The secondary structure of the loop IIId domain in the RNA of hepatitis C virus (HCV) is well-conserved among different genotypes of HCV, which suggests that the nucleocapsid proteins may interact with the genome RNA through this loop structure. Using infrared spectroscopy, we monitored structural changes occurring in HCV core protein and loop IIId upon formation of nucleocapsid-like particles (NLPs). The protein secondary structure of these particles involves beta-sheet enrichment in relation to its protein monomer. The phosphodiester backbone vibrations of loop IIId reflect the predominant C3'-endo conformation of the riboses involved in the RNA A-form and reveal the packaging-imposed transition of the said RNA segments toward single-stranded structure within the NLPs. Intermolecular protein-nucleic acid contacts in these particles involve RNA phosphate groups and positively charged amino acid residues such as arginine and lysine. Two-dimensional correlation spectroscopic analysis of the spectra measured in the course of deuteration shows synchronous cross-peaks correlating two bands assigned to guanine and arginine side chain, which is consistent with the presence of guanine-arginine interactions in these NLPs. This is also supported by the kinetically favored formation of NLPs having HCV core protein and guanine-enriched synthetic oligonucleotides. We also found that these NPLs are fully permeable to water molecules.


Assuntos
Hepacivirus/química , Hepacivirus/metabolismo , Ácidos Nucleicos/química , Ácidos Nucleicos/metabolismo , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/metabolismo , Proteínas do Core Viral/química , Proteínas do Core Viral/metabolismo , Regiões 5' não Traduzidas/genética , Sequência Conservada/genética , Deutério/química , Hepacivirus/genética , Hepacivirus/ultraestrutura , Hidrogênio/química , Ácidos Nucleicos/genética , Proteínas do Nucleocapsídeo/genética , Estrutura Terciária de Proteína/genética , RNA Viral/química , RNA Viral/genética , RNA Viral/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Relação Estrutura-Atividade , Proteínas do Core Viral/genética , Vírion/química , Vírion/genética , Vírion/metabolismo , Montagem de Vírus/genética
19.
Anal Bioanal Chem ; 393(4): 1289-95, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19050855

RESUMO

We describe the improvement of a novel approach to investigating hydrogen/deuterium (H/D) exchange kinetics in biomolecules using transmission infrared spectroscopy. The method makes use of a Fourier transform infrared spectrometer coupled with a microdialysis flow cell to determine exchange rates of labile hydrogens. With this cell system, the monitoring of exchange reactions has been studied here as a function of some cell characteristics such as: (a) dialysis membrane surface contacting both the H(2)O and D(2)O compartments; (b) molecular cutoff of dialysis membrane; and (c) distance between the cell-filling holes. The best improvement has been obtained by increasing the dialysis membrane surface followed by increase of molecular cutoff. However, not significant differences were found using various distances between filling holes. The fastest exchange rate which can be measured with the cell system used here is found to be k = 0.41 +/- 0.02 min(-1), that is, about threefold greater than the one got in a previous work. This microdialysis flow cell has been used here for the study of H/D exchange in nucleic acids with subsequent structural analysis by 2D correlation spectroscopy.


Assuntos
Óxido de Deutério/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Hepacivirus/genética , RNA Viral/química
20.
Proteins ; 66(1): 110-7, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17078073

RESUMO

Electron microscopy and infrared and Raman spectroscopy have been used here to study the morphology, size distribution, secondary and tertiary structures of protein particles assembled from a truncated hepatitis C virus (HCV) core protein covering the first 120 aa. Particles of pure protein, having similar morphology and size distribution of those of nucleocapsids found in sera from HCV-infected patients, have been visualized for the first time. The secondary structure of these protein particles involve beta-sheet enrichment in relation to its protein monomer. Tertiary/quaternary structure has also been studied using the dynamics of H/D exchange. With this aim infrared spectra were measured as a function of H/D exchange time and subsequently analyzed by principal component analysis and two-dimensional correlation spectroscopy. Temporal dynamics of exchange for these protein particles were as follows: arginine residues exchanged first, followed by turn and unordered structures, followed by beta-sheets which may act as linkers of protein monomers.


Assuntos
Proteínas do Core Viral/química , Arginina/metabolismo , Dicroísmo Circular , Medição da Troca de Deutério , Dimerização , Microscopia Eletrônica , Modelos Moleculares , Nucleocapsídeo/química , Nucleocapsídeo/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Proteínas do Core Viral/metabolismo , Montagem de Vírus
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