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1.
Front Neurosci ; 18: 1373837, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784087

RESUMO

Determining the laterality of the seizure onset zone is challenging in frontal lobe epilepsy (FLE) due to the rapid propagation of epileptic discharges to the contralateral hemisphere. There is hemispheric lateralization of autonomic control, and heart rate is modulated by interactions between the sympathetic and parasympathetic nervous systems. Based on this notion, the laterality of seizure foci in FLE might be determined using heart rate variability (HRV) parameters. We explored preictal markers for differentiating the laterality of seizure foci in FLE using HRV parameters. Twelve patients with FLE (6 right FLE and 6 left FLE) were included in the analyzes. A total of 551 (460 left FLE and 91 right FLE) 1-min epoch electrocardiography data were used for HRV analysis. We found that most HRV parameters differed between the left and right FLE groups. Among the machine learning algorithms applied in this study, the light gradient boosting machine was the most accurate, with an AUC value of 0.983 and a classification accuracy of 0.961. Our findings suggest that HRV parameter-based laterality determination models can be convenient and effective tools in clinical settings. Considering that heart rate can be easily measured in real time with a wearable device, our proposed method can be applied to a closed-loop device as a real-time monitoring tool for determining the side of stimulation.

2.
Nat Commun ; 14(1): 8105, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062020

RESUMO

Structural and mechanistic studies on human odorant receptors (ORs), key in olfactory signaling, are challenging because of their low surface expression in heterologous cells. The recent structure of OR51E2 bound to propionate provided molecular insight into odorant recognition, but the lack of an inactive OR structure limited understanding of the activation mechanism of ORs upon odorant binding. Here, we determined the cryo-electron microscopy structures of consensus OR52 (OR52cs), a representative of the OR52 family, in the ligand-free (apo) and octanoate-bound states. The apo structure of OR52cs reveals a large opening between transmembrane helices (TMs) 5 and 6. A comparison between the apo and active structures of OR52cs demonstrates the inward and outward movements of the extracellular and intracellular segments of TM6, respectively. These results, combined with molecular dynamics simulations and signaling assays, shed light on the molecular mechanisms of odorant binding and activation of the OR52 family.


Assuntos
Odorantes , Receptores Odorantes , Humanos , Receptores Odorantes/metabolismo , Microscopia Crioeletrônica , Olfato , Simulação de Dinâmica Molecular , Proteínas de Neoplasias/metabolismo
3.
Comput Biol Med ; 166: 107435, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37741227

RESUMO

Motor imagery (MI)-based brain-computer interfaces are widely employed for improving the rehabilitation of paralyzed people and their quality of life. It has been well documented that brain activity patterns in the primary motor cortex and sensorimotor cortex during MI are similar to those of motor execution/imagery. However, individuals paralyzed owing to various neurological disorders have debilitated activation of the motor control region. Therefore, the differences in brain activation based on the paralysis location should be considered. We analyzed brain activation patterns using the electroencephalogram (EEG) acquired while performing MI on the right upper limb to investigate hemiplegia-related brain activation patterns. Participants with hemiplegia of the right upper limb (n=7) and left upper limb (n=4) performed the MI task within the right upper limb. EEG signals were acquired using 14 channels based on a 10-20 global system, and analyzed for event-related desynchronization (ERD) based on event-related spectral perturbation and functional connectivity, using the weighted phase-lag index of both hemispheres at the location of hemiplegia. Enhanced ERD was found in the ipsilateral region, compared to the contralateral region, after MI of the affected limb. The reduced difference in the centrality of the channels was observed in all subjects, likely reflecting an altered brain network from increased interhemispheric connections. Furthermore, the tendency of distinct network-based features depending on the MI task on the affected limb was diluted between the inter-hemispheres. Analysis of interaction between inter-region using functional connectivity could provide avenues for further investigation of BCI strategy through the brain state of individuals with hemiplegia.

4.
Cell Rep ; 42(7): 112701, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37384533

RESUMO

The 26S proteasome comprises 20S catalytic and 19S regulatory complexes. Approximately half of the proteasomes in cells exist as free 20S complexes; however, our mechanistic understanding of what determines the ratio of 26S to 20S species remains incomplete. Here, we show that glucose starvation uncouples 26S holoenzymes into 20S and 19S subcomplexes. Subcomplex affinity purification and quantitative mass spectrometry reveal that Ecm29 proteasome adaptor and scaffold (ECPAS) mediates this structural remodeling. The loss of ECPAS abrogates 26S dissociation, reducing degradation of 20S proteasome substrates, including puromycylated polypeptides. In silico modeling suggests that ECPAS conformational changes commence the disassembly process. ECPAS is also essential for endoplasmic reticulum stress response and cell survival during glucose starvation. In vivo xenograft model analysis reveals elevated 20S proteasome levels in glucose-deprived tumors. Our results demonstrate that the 20S-19S disassembly is a mechanism adapting global proteolysis to physiological needs and countering proteotoxic stress.


Assuntos
Complexo de Endopeptidases do Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Citoplasma/metabolismo , Proteólise , Espectrometria de Massas
5.
Biosensors (Basel) ; 13(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37366996

RESUMO

Metaphotonic devices, which enable light manipulation at a subwavelength scale and enhance light-matter interactions, have been emerging as a critical pillar in biosensing. Researchers have been attracted to metaphotonic biosensors, as they solve the limitations of the existing bioanalytical techniques, including the sensitivity, selectivity, and detection limit. Here, we briefly introduce types of metasurfaces utilized in various metaphotonic biomolecular sensing domains such as refractometry, surface-enhanced fluorescence, vibrational spectroscopy, and chiral sensing. Further, we list the prevalent working mechanisms of those metaphotonic bio-detection schemes. Furthermore, we summarize the recent progress in chip integration for metaphotonic biosensing to enable innovative point-of-care devices in healthcare. Finally, we discuss the impediments in metaphotonic biosensing, such as its cost effectiveness and treatment for intricate biospecimens, and present a prospect for potential directions for materializing these device strategies, significantly influencing clinical diagnostics in health and safety.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Refratometria , Análise de Custo-Efetividade
6.
J Comput Chem ; 44(14): 1360-1368, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-36847771

RESUMO

Cryo-electron microscopy (cryo-EM) is gaining large attention for high-resolution protein structure determination in solutions. However, a very high percentage of cryo-EM structures correspond to resolutions of 3-5 Å, making the structures difficult to be used in in silico drug design. In this study, we analyze how useful cryo-EM protein structures are for in silico drug design by evaluating ligand docking accuracy. From realistic cross-docking scenarios using medium resolution (3-5 Å) cryo-EM structures and a popular docking tool Autodock-Vina, only 20% of docking succeeded, when the success rate doubles in the same kind of cross-docking but using high-resolution (<2 Å) crystal structures instead. We decipher the reason for failures by decomposing the contribution from resolution-dependent and independent factors. The heterogeneity in the protein side-chain and backbone conformations is identified as the major resolution-dependent factor causing docking difficulty from our analysis, while intrinsic receptor flexibility mainly comprises the resolution-independent factor. We demonstrate the flexibility implementation in current ligand docking tools is able to rescue only a portion of failures (10%), and the limited performance was majorly due to potential structural errors than conformational changes. Our work suggests the strong necessity of more robust method developments on ligand docking and EM modeling techniques in order to fully utilize cryo-EM structures for in silico drug design.


Assuntos
Benchmarking , Proteínas , Microscopia Crioeletrônica/métodos , Ligantes , Proteínas/química , Desenho de Fármacos , Conformação Proteica
7.
Adv Mater ; 35(43): e2200659, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35305277

RESUMO

Vertically integrated NAND (V-NAND) flash memory is the main data storage in modern handheld electronic devices, widening its share even in the data centers where installation and operation costs are critical. While the conventional scaling rule has been applied down to the design rule of ≈15 nm (year 2013), the current method of increasing device density is stacking up layers. Currently, 176-layer-stacked V-NAND flash memory is available on the market. Nonetheless, increasing the layers invokes several challenges, such as film stress management and deep contact hole etching. Also, there should be an upper bound for the attainable stacking layers (400-500) due to the total allowable chip thickness, which will be reached within 6-7 years. This review summarizes the current status and critical challenges of charge-trap-based flash memory devices, with a focus on the material (floating-gate vs charge-trap-layer), array-level circuit architecture (NOR vs NAND), physical integration structure (2D vs 3D), and cell-level programming technique (single vs multiple levels). Current efforts to improve fabrication processes and device performances using new materials are also introduced. The review suggests directions for future storage devices based on the ionic mechanism, which may overcome the inherent problems of flash memory devices.

9.
Rev Sci Instrum ; 92(1): 015103, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514223

RESUMO

The dark-field image (DFI) in a grating interferometer involves the small-angle scattering properties of a material. The microstructure of the material can be characterized by an analysis of the auto-correlation length and the DFI. The feasibility of a DFI in a laboratory x-ray source with grating interferometry has been reported, but a follow-up study is needed. In this study, the random stress distribution was measured in the laboratory environment as an applied study. SiO2 mono-spheres as a cohesive powder with a 0.5 µm particle size were used as the sample. The microstructural changes according to the stresses on the particles were observed by acquiring a DFI along the auto-correlation length. In x-rays, a random two-phase media model was first used to analyze the characteristics of cohesive powder. This study showed that the microstructure of materials and x-ray images could be analyzed in a laboratory environment.

10.
Opt Express ; 28(16): 23284-23293, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32752327

RESUMO

We study an analyzer grating based on a scintillation light blocker for a Talbot-Lau grating interferometer. This is an alternative way to analyze the Talbot self-image without the need for an often difficult to fabricate absorption grating for the incident radiation. The feasibility of this approach using a neutron beam has been evaluated and experiments have been conducted at the cold neutron imaging facility of the NIST center for Neutron Research. The neutron grating interferometer with the proposed analyzer grating successfully produced attenuation, differential phase, and dark-field contrast images. In addition, numerical simulations were performed to simulate the Talbot pattern and visibility using scintillation screens of different thicknesses and there is good agreement with the experimental measurements. The results show potential for reducing the difficulty of fabricating analyzer grating, and a possibility for the so-called shadow effect to be eliminated and large-area gratings to be produced, especially when applied to X-rays. We report the performance of the analyzer grating based on a light blocker and evaluate its feasibility for the grating interferometer.

11.
Sci Rep ; 10(1): 9891, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555276

RESUMO

In Talbot-Lau interferometry, the sample position yielding the highest phase sensitivity suffers from strong geometric blur. This trade-off between phase-sensitivity and spatial resolution is a fundamental challenge in such interferometric imaging applications with either neutron or conventional x-ray sources due to their relatively large beam-defining apertures or focal spots. In this study, a deep learning method is introduced to estimate a high phase-sensitive and high spatial resolution image from a trained neural network to attempt to avoid the trade-off for both high phase-sensitivity and high resolution. To realize this, the training data sets of the differential phase contrast images at a pair of sample positions, one of which is close to the phase grating and the other close to the detector, are numerically generated and are used as the inputs for the training data set of a generative adversarial network. The trained network has been applied to the real experimental data sets from a neutron grating interferometer and we have obtained improved images both in phase-sensitivity and spatial resolution.

12.
Appl Biochem Biotechnol ; 191(4): 1545-1561, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32157625

RESUMO

The role of actin fibers in cellular responses to external electric pulses is not clear yet. In this study, we utilized the blocker of actin polymerization, cytochalasin D (cytoD), and investigated its effects on the electropore generation. Eight 100 µs electric pulses of sub-kilovolt per centimeter voltage with 100 ms intervals were applied to adhered cells in vitro, and the membrane permeability was quantified using membrane-impermeable propidium iodide (PI) dye. With cytoD application, the transfer of PI dye decreased significantly in all the applied voltages. At the same time, the roughness of cells increased, the membrane stiffness decreased, and the transmembrane resting potential decreased. Our result supports that actin fibers have clear effects on electroporation through modulating membrane properties including transmembrane resting potential.


Assuntos
Citoesqueleto de Actina/química , Eletroporação/métodos , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/química , Permeabilidade da Membrana Celular , Citocalasina D/química , Eletricidade , Fibroblastos/química , Humanos , Potenciais da Membrana , Microscopia de Força Atômica , Permeabilidade
13.
Biochem Biophys Res Commun ; 517(4): 703-708, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31387747

RESUMO

Electroporation is used for cancer therapy to efficiently destroy cancer tissues by transferring anticancer drugs into cancer cells or by irreversible tumor ablation without resealing pores. There is growing interest in the electroporation method for the treatment of lung cancer, which has the highest mortality rate among cancers. Improving the cancer cell selectivity has the potential to expand its use. However, the factors that influence the cell selectivity of electroporation are debatable. We aimed to identify the important factors that influence the efficiency of electroporation in lung cells. The electropermeabilization of lung cancer cells (H460, A549, and HCC1588) and normal lung cells (MRC5, WI26 and L132) was evaluated by the transfer of fluorescence dyes. We found that membrane permeabilization increased as cell size, membrane stiffness, resting transmembrane potential, and lipid cholesterol ratio increased. Among them, lipid composition was found to be the most relevant factor in the electroporation of lung cells. Our results provide insight into the differences between lung cancer cells and normal lung cells and provide a basis for enhancing the sensitivity of lung cancers cells to electroporation.


Assuntos
Eletroporação , Neoplasias Pulmonares/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Fluorescência , Humanos
14.
Front Behav Neurosci ; 12: 186, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30333734

RESUMO

A fronto-parietal network, comprised of the posterior parietal cortex (PPC) and the dorsal premotor cortex (PMd) has been proposed to be involved in planning and guiding movement. However, the issue of how the network is expressed across the bilateral cortical area according to the effector's side remains unclear. In this study, we tested these questions using electrocorticographic (ECoG) recordings in non-human primates and using a simple visual guided reaching task that induced a left or right hand response based on relevant cues provided for the task. The findings indicate that right hemisphere lateralized network patterns in which the right PMd was strongly coordinated with bilateral PPC immediately after presentation of the movement cue occurred, while the coherence with the left PMd was not enhanced. No difference was found in the coherence pattern between the effector's side (left hand or right hand), but the strength of coherence was different, in that animals showed a higher coherence in the right hand response compared to the left. Our data support that right lateralization in long-range phase synchrony in the 10-20 Hz low beta band is involved in motor preparation stage, irrespective of the upcoming effector's side.

15.
J Neurosci Methods ; 308: 261-268, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29964082

RESUMO

BACKGROUND: A screw-shaped electrode can offer a compromise between signal quality and invasiveness. However, the standard screw electrode can be vulnerable to electrical noise while directly contact with the skull or skin, and the feasibility and stability for chronic implantation in primate have not been fully evaluated. NEW METHOD: We designed a novel screw electrocorticogram (ECoG) electrode composed of three parts: recording electrode, insulator, and nut. The recording electrode was made of titanium with high biocompatibility and high electrical conductivity. Zirconia is used for insulator and nut to prevent electrical noise. RESULT: In computer simulations, the screw ECoG with insulator showed a significantly higher performance in signal acquisition compared to the condition without insulator. In a non-human primate, using screw ECoG, clear visual-evoked potential (VEP) waveforms were obtained, VEP components were reliably maintained, and the electrode's impedance was stable during the whole evaluation period. Moreover, it showed higher SNR and wider frequency band compared to the electroencephalogram (EEG). We also observed the screw ECoG has a higher sensitivity that captures different responses on various stimuli than the EEG. COMPARISON: The screw ECoG showed reliable electrical characteristic and biocompatibility for three months, that shows great promise for chronic implants. These results contrasted with previous reports that general screw electrode was only applicable for acute applications. CONCLUSION: The suggested electrode can offer whole-brain monitoring with high signal quality and minimal invasiveness. The screw ECoG can be used to provide more in-depth understanding, not only relationship between functional networks and cognitive behavior, but also pathomechanisms in brain diseases.


Assuntos
Parafusos Ósseos , Mapeamento Encefálico/instrumentação , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletrocorticografia/instrumentação , Eletrocorticografia/métodos , Eletrodos Implantados , Animais , Artefatos , Simulação por Computador , Eletroencefalografia , Campos Eletromagnéticos , Fenômenos Eletrofisiológicos , Estudos de Viabilidade , Macaca mulatta , Razão Sinal-Ruído
16.
J Neural Eng ; 15(1): 016011, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28875947

RESUMO

OBJECTIVE: In arm movement BCIs (brain-computer interfaces), unimanual research has been much more extensively studied than its bimanual counterpart. However, it is well known that the bimanual brain state is different from the unimanual one. Conventional methodology used in unimanual studies does not take the brain stage into consideration, and therefore appears to be insufficient for decoding bimanual movements. In this paper, we propose the use of a two-staged (effector-then-trajectory) decoder, which combines the classification of movement conditions and uses a hand trajectory predicting algorithm for unimanual and bimanual movements, for application in real-world BCIs. APPROACH: Two micro-electrode patches (32 channels) were inserted over the dura mater of the left and right hemispheres of two rhesus monkeys, covering the motor related cortex for epidural electrocorticograph (ECoG). Six motion sensors (inertial measurement unit) were used to record the movement signals. The monkeys performed three types of arm movement tasks: left unimanual, right unimanual, bimanual. To decode these movements, we used a two-staged decoder, which combines the effector classifier for four states (left unimanual, right unimanual, bimanual movements, and stationary state) and movement predictor using regression. MAIN RESULTS: Using this approach, we successfully decoded both arm positions using the proposed decoder. The results showed that decoding performance for bimanual movements were improved compared to the conventional method, which does not consider the effector, and the decoding performance was significant and stable over a period of four months. In addition, we also demonstrated the feasibility of epidural ECoG signals, which provided an adequate level of decoding accuracy. SIGNIFICANCE: These results provide evidence that brain signals are different depending on the movement conditions or effectors. Thus, the two-staged method could be useful if BCIs are used to generalize for both unimanual and bimanual operations in human applications and in various neuro-prosthetics fields.


Assuntos
Interfaces Cérebro-Computador , Eletrocorticografia/métodos , Córtex Motor/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Previsões , Macaca mulatta , Estimulação Luminosa/métodos , Distribuição Aleatória , Extremidade Superior/fisiologia
17.
Aerosp Med Hum Perform ; 88(9): 866-870, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28818146

RESUMO

INTRODUCTION: In the Republic of Korea Air Force, the health of pilots is strictly supervised, but there is comparatively not enough interest in aircraft mechanics' health. Among mechanics, who are heavily involved in military aircraft maintenance, the occurrence of sudden cardio-cerebrovascular diseases (CCVDs) is a possible risk factor during the maintenance process, which should be performed perfectly. METHODS: We performed health examinations on 2123 male aircraft pilots and 1271 aircraft mechanics over 30 yr of age and determined the prevalence of metabolic syndrome (MetS), an important risk factor for CCVDs. RESULTS: The prevalence of MetS in the aircraft mechanics (21.3%) was significantly higher than in the pilots (12.6%), and the gap in prevalence tended to grow as age increased. Among aircraft mechanics in their 30s and 40s, the prevalence of MetS was lower than in the general population. However, the prevalence of MetS among aircraft mechanics in their 50s (36.0%) was similar to that in the general population (35.7%). CONCLUSIONS: Systematic health management is needed for aircraft mechanics for aviation safety and for the maintenance of military strength via the prevention of CCVDs.Kim M-B, Kim H-J, Kim S-H, Lee S-H, Lee S-H, Park W-J. Metabolic syndrome and cardio-cerebrovascular risk disparities between pilots and aircraft mechanics. Aerosp Med Hum Perform. 2017; 88(9):866-870.


Assuntos
Síndrome Metabólica/epidemiologia , Militares , Pilotos , Adulto , Medicina Aeroespacial , Doenças Cardiovasculares/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Fatores de Risco
18.
J Korean Med Sci ; 32(8): 1243-1250, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28665058

RESUMO

A brain-computer interface (BCI) can be used to restore some communication as an alternative interface for patients suffering from locked-in syndrome. However, most BCI systems are based on SSVEP, P300, or motor imagery, and a diversity of BCI protocols would be needed for various types of patients. In this paper, we trained the choice saccade (CS) task in 2 non-human primate monkeys and recorded the brain signal using an epidural electrocorticogram (eECoG) to predict eye movement direction. We successfully predicted the direction of the upcoming eye movement using a support vector machine (SVM) with the brain signals after the directional cue onset and before the saccade execution. The mean accuracies were 80% for 2 directions and 43% for 4 directions. We also quantified the spatial-spectro-temporal contribution ratio using SVM recursive feature elimination (RFE). The channels over the frontal eye field (FEF), supplementary eye field (SEF), and superior parietal lobule (SPL) area were dominantly used for classification. The α-band in the spectral domain and the time bins just after the directional cue onset and just before the saccadic execution were mainly useful for prediction. A saccade based BCI paradigm can be projected in the 2D space, and will hopefully provide an intuitive and convenient communication platform for users.


Assuntos
Eletrocorticografia , Movimentos Sacádicos/fisiologia , Animais , Interfaces Cérebro-Computador , Lobo Frontal/fisiologia , Macaca mulatta , Masculino , Lobo Parietal/fisiologia , Máquina de Vetores de Suporte
19.
J Korean Med Sci ; 31(4): 497-501, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27051231

RESUMO

Military personnel often use ammunitions that contain lead. The present study aimed to identify the risks for lead exposure and lead poisoning among workers at indoor firing ranges. A special health examination, including blood lead level (BLL) testing, was performed for all 120 workers at the indoor firing ranges of the Republic of Korea's Air Force, Navy, and Armed Forces Athletic Corps. The overall mean BLL was 11.3 ± 9.4 µg/dL (range: 2.0-64.0 µg/dL). The arithmetic mean of the BLL for professional shooters belong to Armed Forces Athletic Corps was 14.0 ± 8.3 µg/dL, while those of shooting range managers and shooting range supervisors were 13.8 ± 11.1 µg/dL and 6.4 ± 3.1 µg/dL, respectively. One individual had a BLL of 64 µg/dL, and ultimately completed chelation treatment (with CaNa2-ethylenediaminetetraacetic acid) without any adverse effects. These findings indicate that indoor firing range workers are exposed to elevated levels of lead. Therefore, when constructing an indoor firing range, a specialist should be engaged to design and assess the ventilation system; and safety guidelines regarding ammunition and waste handling must be mandatory. Moreover, workplace environmental monitoring should be implemented for indoor firing ranges, and the workers should undergo regularly scheduled special health examinations.


Assuntos
Poluentes Atmosféricos/sangue , Chumbo/sangue , Exposição Ocupacional/análise , Adulto , Poluição do Ar em Ambientes Fechados , Ingestão de Líquidos , Ácido Edético/química , Feminino , Armas de Fogo , Humanos , Chumbo/química , Masculino , Militares , Razão de Chances , República da Coreia , Fatores de Risco , Espectrofotometria Atômica , Adulto Jovem
20.
Rev Sci Instrum ; 85(2): 026111, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593411

RESUMO

Given that approximately 80% of blood is water, we develop a wireless functional near-infrared spectroscopy system that detects not only the concentration changes of oxy- and deoxy-hemoglobin (HbO and HbR) during mental activity but also that of water (H2O). Additionally, it implements a water-absorption correction algorithm that improves the HbO and HbR signal strengths during an arithmetic task. The system comprises a microcontroller, an optical probe, tri-wavelength light emitting diodes, photodiodes, a WiFi communication module, and a battery. System functionality was tested by means of arithmetic-task experiments performed by healthy male subjects.


Assuntos
Hemoglobinas/metabolismo , Luz , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Água/química , Absorção , Algoritmos , Hemoglobinas/química , Humanos , Masculino , Oxiemoglobinas/química , Água/metabolismo , Tecnologia sem Fio
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