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Oil spills are a paramount and immediate challenge affecting marine ecosystems globally. Effective and timely monitoring tools, such as oil detection indices, offer a swift means to track oil spill spread across vast oceanic expanses. Moreover, these indices enhance data clarity, making it more conducive for machine learning and deep learning algorithms. This study leverages the natural seepage occurring around Qaruh Island, Kuwait as a unique context for the spectral analysis of oil spills using Sentinel-2 multispectral imagery due to repeated occurrences in the same region. This research evaluated 859 single band and 455 multichannel combinations to identify the most effective combinations in oil-water separability, employing the Jeffries-Matusita (JM) distance measure as a key metric. Bands 1, 2, 3, 8A, 11, and 12 consistently featured among the top-performing indices combinations B1-B11B1+B11;B1+B2B3+B11;B1+B2B3+B12;B1+B2B3+B8A affirming the significant effect of oil spills on visible, Near-Infrared (NIR), and Shortwave Infrared (SWIR) bands. Notably, the indices developed in this study outperformed those from prior research in terms of suitability to unsupervised classification algorithms. A significant conclusion of this study is that incorporating a higher number of bands in the analysis did not correlate with an increase in JM values, suggesting that the selection of specific, informative bands is more critical than the volume of input data. These findings underscore the indispensable role of Sentinel-2 imagery in environmental investigations and highlight the potential for focused, efficient analysis using strategic band combinations for effective oil spill detection.â¢This study identified optimized Sentinel-2 band combinations for oil-water separability, benefiting from naturally occurring spills around Qaruh Island.â¢The proposed indices outperformed the previous indices for oil spill visualization and clustering.â¢The new indices highlighted the critical role of specific band selection over the volume of input data for effective oil spill detection.
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Microgreens have gained attention for their exceptional culinary characteristics and high nutritional value. The present study focused on a novel approach for investigating the easy extraction of plant samples and the utilization of immersible silicon photonic sensors to determine, on the spot, the nutrient content of microgreens and their optimum time of harvest. For the first time, it was examined how these novel sensors can capture time-shifting spectra caused by the molecules' dynamic adhesion onto the sensor surface. The experiment involved four types of microgreens (three types of basil and broccoli) grown in a do-it-yourself hydroponic installation. The sensors successfully distinguished between different plant types, showcasing their discriminative capabilities. To determine the optimum harvest time, this study compared the sensor data with results obtained through standard analytical methods. Specifically, the total phenolic content and antioxidant activity of two basil varieties were juxtaposed with the sensor data, and this study concluded that the ideal harvest time for basil microgreens was 14 days after planting. This finding highlights the potential of the immersible silicon photonic sensors for potentially replacing time-consuming analytical techniques. By concentrating on obtaining plant extracts, capturing time-shifting spectra, and assessing sensor reusability, this research paves the way for future advancements in urban farming.
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Brassica , Silício , Estudos de Viabilidade , Antioxidantes , NutrientesRESUMO
BACKGROUND: Motor impairment is a common consequence of stroke causing difficulty in independent movement. The first month of post-stroke rehabilitation is the most effective period for recovery. Movement imagination, known as motor imagery, in combination with virtual reality may provide a way for stroke patients with severe motor disabilities to begin rehabilitation. METHODS: The aim of this study is to verify whether motor imagery and virtual reality help to activate stroke patients' motor cortex. 16 acute/subacute (< 6 months) stroke patients participated in this study. All participants performed motor imagery of basketball shooting which involved the following tasks: listening to audio instruction only, watching a basketball shooting animation in 3D with audio, and also performing motor imagery afterwards. Electroencephalogram (EEG) was recorded for analysis of motor-related features of the brain such as power spectral analysis in the [Formula: see text] and [Formula: see text] frequency bands and spectral entropy. 18 EEG channels over the motor cortex were used for all stroke patients. RESULTS: All results are normalised relative to all tasks for each participant. The power spectral densities peak near the [Formula: see text] band for all participants and also the [Formula: see text] band for some participants. Tasks with instructions during motor imagery generally show greater power spectral peaks. The p-values of the Wilcoxon signed-rank test for band power comparison from the 18 EEG channels between different pairs of tasks show a 0.01 significance of rejecting the band powers being the same for most tasks done by stroke subjects. The motor cortex of most stroke patients is more active when virtual reality is involved during motor imagery as indicated by their respective scalp maps of band power and spectral entropy. CONCLUSION: The resulting activation of stroke patient's motor cortices in this study reveals evidence that it is induced by imagination of movement and virtual reality supports motor imagery. The framework of the current study also provides an efficient way to investigate motor imagery and virtual reality during post-stroke rehabilitation.
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Basquetebol , Imaginação , Transtornos Motores , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Humanos , Eletroencefalografia/métodos , Imaginação/fisiologia , Transtornos Motores/etiologia , Transtornos Motores/fisiopatologia , Transtornos Motores/reabilitação , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Córtex Motor/fisiopatologia , Basquetebol/fisiologia , Basquetebol/psicologia , Ondas Encefálicas/fisiologiaRESUMO
The vascular structure and function are potentially useful biomarkers for tumor detection. Treatment with chemotherapeutic agents may impair vascular function and increase the risk of cardiovascular disease. This study aimed to use noninvasive pulse waveform measurements to identify differences in the frequency-domain indices of the pulse waveform in breast-cancer patients following anthracycline chemotherapy between with (Group KSY) and without (Group NKSY) receiving Kuan-Sin-Yin (KSY) treatment.Radial blood pressure waveform (BPW) signals were measured noninvasively for 3 minutes in 31 patients, and the FACT-G, BFI-T, and EORTC QLQ-C30 questionnaires were administered. The following pulse indices were calculated for 10 harmonics: the amplitude proportion and its coefficient of variation, and the phase angle and its standard deviation.The changes in spectral BPW indices were more prominent in Group NKSY than in Group KSY, especially for the decreases in BPW variability indices. Scores on the FACT-G, BFI-T, and EORTC QLQ-C30 questionnaires suggested that the quality of life following chemotherapy was better in Group KSY.The identified decreases in pulse variability indices could be related to the greater impairment of regulatory activities in Group NKSY. The present findings may be meaningful in developing techniques with advantages such as being noninvasive and time-saving to evaluate the blood supply and physiological conditions following chemotherapy or other treatment strategies in cancer patients.
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Neoplasias da Mama , Qualidade de Vida , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Antraciclinas/efeitos adversos , Medicina Tradicional Chinesa/métodos , Inquéritos e QuestionáriosRESUMO
Okra pods have been utilized as a functional food due to their rich active ingredient composition, especially the high content of flavonoid compounds. This study conducted near-infrared spectroscopy (NIRS) modeling optimization and external validation based on the flavonoid components of 219 pod samples. Spectral correlation analyses identified two types of spectral response patterns classified as quercetin-3-O-xylose (1-2) glucoside (QOXG) and total flavonoid content (TFC), consisting of six different spectral regions. Different modeling effects were observed for QOXG and TFC with various spectral region combination analyses, where the lower wave-number region contributed more to both flavonoids calibration models. The combination of standard normal variate / "1, 9, 3" / partial least squares was found to be the most effective for developing calibration models for both flavonoids. The resulting models had small root mean square errors of prediction for external validation and high determination coefficients, indicating their usefulness for rapid prediction of flavonoid composition in okra pods.
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Abelmoschus , Flavonoides , Flavonoides/análise , Abelmoschus/química , Quercetina/química , Antioxidantes/química , Extratos Vegetais/química , Análise dos Mínimos QuadradosRESUMO
Anxiety and mindfulness are two inversely linked traits shown to be involved in various physiological domains. The current study used resting state electroencephalography (EEG) to explore differences between people with low mindfulness-high anxiety (LMHA) (n = 29) and high mindfulness-low anxiety (HMLA) (n = 27). The resting EEG was collected for a total of 6 min, with a randomized sequence of eyes closed and eyes opened conditions. Two advanced EEG analysis methods, Holo-Hilbert Spectral Analysis and Holo-Hilbert cross-frequency phase clustering (HHCFPC) were employed to estimate the power-based amplitude modulation of carrier frequencies, and cross-frequency coupling between low and high frequencies, respectively. The presence of higher oscillation power across the delta and theta frequencies in the LMHA group than the HMLA group might have been due to the similarity between the resting state and situations of uncertainty, which reportedly triggers motivational and emotional arousal. Although these two groups were formed based on their trait anxiety and trait mindfulness scores, it was anxiety that was found to be significant predictor of the EEG power, not mindfulness. It led us to conclude that it might be anxiety, not mindfulness, which might have contributed to higher electrophysiological arousal. Additionally, a higher δ-ß and δ-γ CFC in LMHA suggested greater local-global neural integration, consequently a greater functional association between cortex and limbic system than in the HMLA group. The present cross-sectional study may guide future longitudinal studies on anxiety aiming with interventions such as mindfulness to characterize the individuals based on their resting state physiology.
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Ansiedade , Eletroencefalografia , Humanos , Transtornos de Ansiedade , Córtex Cerebral/fisiologia , Estudos Transversais , Eletroencefalografia/métodosRESUMO
Shigellosis is a serious foodborne diarrheal disease caused by the Shigella species. It is a critical global health issue. In developing countries, shigellosis causes most of the mortality in children below 5 years of age. Globally, around 165 million cases of diarrhea caused by Shigella are reported, which accounts for almost 1 million deaths, in which the majority are recorded in Third World nations. In this study, silver nanoparticles were synthesized using Mangifera indica kernel (MK-AgNPs) seed extracts. The biosynthesized M. indica silver nanoparticles (MK-AgNPs) were characterized using an array of spectroscopic and microscopic tools, such as UV-Vis, scanning electron microscopy, particle size analyzer, Fourier transform infrared spectroscopy, and X-ray diffractometer. The nanoparticles were spherical in shape and the average size was found to be 42.7 nm. The MK-AgNPs exhibited remarkable antibacterial activity against antibiotic-resistant clinical Shigella sp. The minimum inhibitory concentration (MIC) value of the MK-AgNPs was found to be 20 µg/mL against the multi-drug-resistant strain Shigella flexneri. The results clearly demonstrate that MK-AgNPs prepared using M. indica kernel seed extract exhibited significant bactericidal action against pathogenic Shigella species. The biosynthesized nanoparticles from mango kernel could possibly prove therapeutically useful and effective in combating the threat of shigellosis after careful investigation of its toxicity and in vivo efficacy.
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Disenteria Bacilar , Mangifera , Nanopartículas Metálicas , Shigella , Criança , Humanos , Mangifera/química , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Disenteria Bacilar/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , SementesRESUMO
Driven by economic benefits like any other foods, vegetable oil has long been plagued by mislabeling and adulteration. Many studies have addressed the field of classification and identification of vegetable oils by various analysis techniques, especially spectral analysis. A comparative study was performed using Fourier transform infrared spectroscopy (FTIR), visible near-infrared spectroscopy (Vis-NIR) and excitation-emission matrix fluorescence spectroscopy (EEMs) combined with chemometrics to distinguish different types of edible vegetable oils. FTIR, Vis-NIR and EEMs datasets of 147 samples of five vegetable oils from different brands were analyzed. Two types of pattern recognition methods, principal component analysis (PCA)/multi-way principal component analysis (M-PCA) and partial least squares discriminant analysis (PLS-DA)/multilinear partial least squares discriminant analysis (N-PLS-DA), were used to resolve these data and distinguish vegetable oil types, respectively. PCA/M-PCA analysis exhibited that three spectral data of five vegetable oils showed a clustering trend. The total correct recognition rate of the training set and prediction set of FTIR spectra of vegetable oil based on PLS-DA method are 100%. The total recognition rate of Vis-NIR based on PLS-DA are 100% and 97.96%. However, the total correct recognition rate of training set and prediction set of EEMs data based on N-PLS-DA method is 69.39% and 75.51%, respectively. The comparative study showed that FTIR and Vis-NIR combined with chemometrics were more suitable for vegetable oil species identification than EEMs technique. The reason may be concluded that almost all chemical components in vegetable oil can produce FTIR and NIR absorption, while only a small amount of fluorophores can produce fluorescence. That is, FTIR and NIR can provide more spectral information than EEMs. Analysis of EEMs data using self-weighted alternating trilinear decomposition (SWATLD) also showed that fluorophores were a few and irregularly distributed in vegetable oils.
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Óleos de Plantas , Verduras , Óleos de Plantas/química , Espectrometria de Fluorescência/métodos , Quimiometria , Análise Discriminante , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise dos Mínimos QuadradosRESUMO
The purpose of this study was to identify the chemical components in aerial parts of Hypecoum erectum. A new 1,3-benzodioxole derivative, identified as Hypecoumic acid (1), was isolated, together with the three known compounds: protopine (2), coptisine (3), and cryptopine (4). Their structures were identified based on extensive spectroscopic experiments, including nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectra (HR-ESI-MS), as well as comparison with those reported in the literature. Meanwhile, the in vitro antioxidative activity of all compounds was determined using a DPPH-scavenging assay, and compound 1 (IC50 = 86.3 ± 0.2 µM) was shown to have moderate antioxidative activity.
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Antioxidantes , Espectrometria de Massas por Ionização por Electrospray , Antioxidantes/química , Antioxidantes/farmacologia , Dioxóis , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
The network pharmacology under conditions is a recent development trend. We use network pharmacology methods to analyze the mechanism of crocetin (CRO) that regulates cardiovascular diseases. In this work, the spectral experimental data of CRO-Protein interaction is first time combined with constraint conditions to solve the problems of targeting redundancy and lack of verification. CRO targets and cardiovascular disease targets were obtained by the target database. The STRING platform was used for PPI analysis. The GO and KEGG pathways of the target were analyzed using the Metascape platform; The core functional targets of CRO were screened by molecular docking techniques and the spectra of CRO and human serum albumin (HSA). Under the collaborative constraint conditions, the core targets of CRO that regulate cardiovascular diseases are ADRA1A, ADRA1B, CHRM1, CHRM2, GABRA1, and PTGS2; This study incorporates spectroscopy and molecular docking as constraints into the network pharmacological analysis, which significantly improves the credibility of network pharmacological analysis compared with unconstrained conditions. This method provides theoretical references for the in-depth study of the mechanism between active substances and protein targets for other medicines in network pharmacology.
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Doenças Cardiovasculares , Medicamentos de Ervas Chinesas , Humanos , Simulação de Acoplamento Molecular , Doenças Cardiovasculares/tratamento farmacológico , Farmacologia em Rede , Carotenoides/farmacologia , Carotenoides/química , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Receptor Muscarínico M1 , Receptores Adrenérgicos alfa 1RESUMO
A novel swarm intelligence algorithm, discretized grey wolf optimizer (GWO), was introduced as a variable selection tool in edible blend oil analysis for the first time. In the approach, positions of wolves were updated and then discretized by logical function. The performance of a wolf pack, the iteration number and the number of wolves were investigated. The partial least squares (PLS) method was used to establish and predict single oil contents in samples. To validate the method, 102 edible blend oil samples containing soybean oil, sunflower oil, peanut oil and sesame oil were measured by an ultraviolet-visible (UV-Vis) spectrophotometer. The results demonstrated that GWO-PLS models can provide best prediction accuracy with least variables compared with full-spectrum PLS, Monte Carlo uninformative variable elimination-PLS (MCUVE-PLS) and randomization test-PLS (RT-PLS). The determination coefficients (R2) of GWO-PLS were all above 0.95. Therefore, the research indicates the feasibility of using discretized GWO for variable selection in rapid determination of quaternary edible blend oil.
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Algoritmos , Óleo de Soja , Análise dos Mínimos Quadrados , Óleo de Amendoim , Óleo de Soja/análise , Espectrofotometria Ultravioleta , Óleo de GirassolRESUMO
BACKGROUND: Very preterm (VPT) infants develop adverse neurological sequelae from early exposure of the immature brain to the extrauterine environment. AIMS: To determine the effects of infant massage on brain maturation in low-risk VPT infants. STUDY DESIGN: A randomised controlled trial of VPT infants, who received standard care or daily massage therapy, administered by the mother, from 34 weeks' to 40 weeks' corrected age (CA). SUBJECTS: VPT infants (born at 28 weeks to 32 + 6 weeks' gestational age, G.A.) and a healthy at term cohort for comparison. OUTCOME MEASURES: At term equivalent age (39 weeks' to 42 weeks' CA), EEG was recorded to calculate global relative power (GRP), using power spectral analysis. RESULTS: Sixty infants were recruited, and EEGs of 25 massage and 20 standard care infants were analysable. There was no difference between groups in primary outcome (beta GRP). There was a significantly higher central alpha relative power measured in the intervention group infants, compared to standard care (SC) group (mean difference = 1.42, 95 % confidence interval (CI): 0.12 to 2.73; p = 0.03). A massage dose effect was shown by a positive correlation between, massage dose and beta, alpha and theta GRP (r = 0.42, 95%CI = 0.12 to 0.64, r = 0.45; 95%CI = 0.16 to 0.66, r = 0.39; 95%CI = 0.10 to 0.62 respectively) and a negative correlation between massage dose and delta GRP (r = -0.41, 95%CI = -0.64 to -0.12), suggesting that a higher dose of massage is associated with more favourable brain maturation. CONCLUSIONS: Central alpha regional relative power was greater in massaged infants compared to SC group infants, suggesting relatively greater brain maturation in this area. A measurable massage dose effect in favour of greater brain maturation, shows promise for verification in a larger clinical trial.
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Doenças do Prematuro , Recém-Nascido Prematuro , Encéfalo , Eletroencefalografia , Feminino , Retardo do Crescimento Fetal , Idade Gestacional , Humanos , Lactente , Recém-Nascido , MassagemRESUMO
BACKGROUND: Heart rate variability (HRV) is one of the tools that can assess autonomic activities during exercise or recovery. Massage is an often-used recovery method with varying recovery outcome. This study was to investigate the effect of lower limb massage on recovery HRV following repeated knee flexion and extension exercise-to-exhaustion. METHODS: Nine healthy men aged between 20 and 30 years old were recruited and randomly assigned to a control group (n = 5) and massage group (n = 4). The HRV spectral analysis was performed at baseline, pre-exercise, post-exercise and immediately post-intervention. For intervention, the participants in the massage group received a 10-min massage on the quadriceps and hamstring muscles of the dominant leg whereas the control group received none. The HRV was presented as low-frequency (LF) peak (Hz), power (ms2), power (normalised unit; n.u.) and high-frequency (HF), peak (Hz), power (ms2), power (n.u.) as well as LF/HF ratio. RESULTS: Spectral power analysis showed there were no significant differences in the LF indices and LF/HF ratio with massage. HRV normalisation data revealed a within-subject difference with massage. CONCLUSIONS: Massage caused an immediate parasympathetic activation during recovery from a single exhaustive muscle contraction exercise. Hence, massage may be used to potentiate recovery.
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Sistema Nervoso Autônomo , Exercício Físico , Adulto , Sistema Nervoso Autônomo/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Massagem , Contração Muscular , Adulto JovemRESUMO
Vagus nerve stimulation (VNS) facilitates weight loss in animals and patients treated with VNS for depression or epilepsy. Likewise, chronic transcutaneous auricular VNS (taVNS) reduces weight gain and improves glucose tolerance in Zucker diabetic fatty rats. If these metabolic effects of taVNS observed in rats translate to humans is unknown. Therefore, the hypothesis of this study was that acute application of taVNS affects glucotropic and orexigenic hormones which could potentially facilitate weight loss and improve glucose tolerance if taVNS were applied chronically. In two single-blinded randomized cross-over protocols, blood glucose levels, plasma concentrations of insulin, C-peptide, glucagon, leptin, and ghrelin, together with heart rate variability and baroreceptor-heart rate reflex sensitivity were determined before and after taVNS (left ear, 10 Hz, 300 µs, 2.0-2.5 mA, 30 min) or sham-taVNS (electrode attached to ear with the stimulator turned off). In a first protocol, subjects (n = 16) were fasted throughout the protocol and in a second protocol, subjects (n = 10) received a high-calorie beverage (220 kCal) after the first blood sample, just before initiation of taVNS or sham-taVNS. No significant effects of taVNS on heart rate variability and baroreceptor-heart rate reflex sensitivity and only minor effects on glucotropic hormones were observed. However, in the second protocol taVNS significantly lowered postprandial plasma ghrelin levels (taVNS: -115.5 ± 28.3 pg/ml vs. sham-taVNS: -51.2 ± 30.6 pg/ml, p < 0.05). This finding provides a rationale for follow-up studies testing the hypothesis that chronic application of taVNS may reduce food intake through inhibition of ghrelin and, therefore, may indirectly improve glucose tolerance through weight loss.
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Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Animais , Grelina , Glucose , Humanos , Ratos , Ratos Zucker , Estimulação Elétrica Nervosa Transcutânea/métodos , Nervo Vago/fisiologia , Estimulação do Nervo Vago/métodos , Redução de PesoRESUMO
Nicotinic acid is an aphrodisiac, co-crystalized with catechol [NICCAT] in Zwitterionic structure used as unorthodox drugs. The present study, investigates its molecular structure, using X-ray diffraction and q chemical optimization technique. An examination of single-crystal XRD reported that crystal packing was highly stabilized with N.H···O and O-H···O. Hydrogen bond synthons. Besides, a weak C-H···O affinity was also contributed to the powerful molecular construction in crystal packing. To geometrically optimize the molecular structure, we employed the Density Functional Theory (DFT), by adopting the B3LYP function and Hartree-Fock (HF) level, with 6-311++G (d, p) a basic set. Moreover, spectral analyses were detected within an excitation range of 4000-400 cm-1 using FT.IR and FT-Raman spectroscopy. A comprehensive analysis was executed by comparing optimized molecular geometries and computed excitation spectra with their respective experimental model counterparts. NICCAT thermodynamic functions were detected in the range of 100-1000 K. The thermal strong stability of developed crystals was evaluated by TGA/DTA measured. Powerful biological actions on humans cervical cancer cell line was observed and proved to be effective. The in vitro and in silico anticancer studies show that NICCAT has better activity against human cervical cancer cell line (HeLa) and in bioinformatics analysis.
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Antineoplásicos , Niacina , Neoplasias do Colo do Útero , Antineoplásicos/farmacologia , Catecóis/farmacologia , Suplementos Nutricionais , Feminino , Células HeLa , Humanos , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Neoplasias do Colo do Útero/tratamento farmacológico , VibraçãoRESUMO
Recent studies have shown that applying acupuncture during general anesthesia can reduce the dosage of anesthetics. Hence, it is speculated that acupuncture may have a sedative effect. However, existing studies employed acupuncture in combination with anesthetics, which makes determine acupuncture's role in producing sedation difficult. In this work, we investigated the sedative effect of acupuncture by using transcutaneous acupoint electrical stimulation (TAES) at bilateral Zusanli (ST36), Shenmen (HT7) and Sanyinjiao (SP6). Using a cross-over design, 2 separate sessions, that are, the resting and TAES sessions, were conducted for each subject. The sedative effect was quantified by using the bispectral index (BIS). The difference in brain activities between resting and TAES sessions was investigated by analyzing the simultaneously recorded EEG signals. Our results showed that a statistically significant difference in BIS values existed between resting and TAES sessions, which suggested that TAES alone was capable of inducing observable sedation. Using power spectrum analysis, we showed that TAES-induced sedation was accompanied by a reduction in alpha band power and an increment in delta band power. Permutation entropy was lower during the TAES session, which suggested that TAES reduced the complexity of the EEG signal. Moreover, a significant reduction in the global strength of brain functional connections was observed during TAES. These findings suggest that TAES alone can induce observable sedative effects, and this sedation effect is accompanied by changes in brain activities that have shown to be correlated with consciousness.
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Pontos de Acupuntura , Estimulação Elétrica Nervosa Transcutânea , Anestesia Geral , Estimulação Elétrica , Eletroencefalografia , HumanosRESUMO
Meditation practices have been claimed to have a positive effect on the regulation of mood and emotions for quite some time by practitioners, and in recent times there has been a sustained effort to provide a more precise description of the influence of meditation on the human brain. Longitudinal studies have reported morphological changes in cortical thickness and volume in selected brain regions due to meditation practice, which is interpreted as an evidence its effectiveness beyond the subjective self reporting. Using magnetoencephalography (MEG) or electroencephalography to quantify the changes in brain activity during meditation practice represents a challenge, as no clear hypothesis about the spatial or temporal pattern of such changes is available to date. In this article we consider MEG data collected during meditation sessions of experienced Buddhist monks practicing focused attention (Samatha) and open monitoring (Vipassana) meditation, contrasted by resting state with eyes closed. The MEG data are first mapped to time series of brain activity averaged over brain regions corresponding to a standard Destrieux brain atlas. Next, by bootstrapping and spectral analysis, the data are mapped to matrices representing random samples of power spectral densities in [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] frequency bands. We use linear discriminant analysis to demonstrate that the samples corresponding to different meditative or resting states contain enough fingerprints of the brain state to allow a separation between different states, and we identify the brain regions that appear to contribute to the separation. Our findings suggest that the cingulate cortex, insular cortex and some of the internal structures, most notably the accumbens, the caudate and the putamen nuclei, the thalamus and the amygdalae stand out as separating regions, which seems to correlate well with earlier findings based on longitudinal studies.
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Magnetoencefalografia , Meditação , Encéfalo , Análise Discriminante , Humanos , Córtex Insular , Fatores de TempoRESUMO
A wide spectrum of brain rhythms are engaged throughout the human cortex in cognitive functions. How the rhythms of various frequency ranges are coordinated across the space of the human cortex and time of memory processing is inconclusive. They can either be coordinated together across the frequency spectrum at the same cortical site and time or induced independently in particular bands. We used a large dataset of human intracranial electroencephalography (iEEG) to parse the spatiotemporal dynamics of spectral activities induced during formation of verbal memories. Encoding of words for subsequent free recall activated low frequency theta, intermediate frequency alpha and beta, and high frequency gamma power in a mosaic pattern of discrete cortical sites. A majority of the cortical sites recorded activity in only one of these frequencies, except for the visual cortex where spectral power was induced across multiple bands. Each frequency band showed characteristic dynamics of the induced power specific to cortical area and hemisphere. The power of the low, intermediate, and high frequency activities propagated in independent sequences across the visual, temporal and prefrontal cortical areas throughout subsequent phases of memory encoding. Our results provide a holistic, simplified model of the spectral activities engaged in the formation of human memory, suggesting an anatomically and temporally distributed mosaic of coordinated brain rhythms.
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Eletroencefalografia/métodos , Memória/fisiologia , Adulto , Conjuntos de Dados como Assunto , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios XRESUMO
Panax ginseng has been used as a traditional medicine to strengthen human health for centuries. Over the last decade, significant agronomical progress has been made in the development of elite ginseng cultivars, increasing their production and quality. However, as one of the significant environmental factors, heat stress remains a challenge and poses a significant threat to ginseng plants' growth and sustainable production. This study was conducted to investigate the phenotype of ginseng leaves under heat stress using hyperspectral imaging (HSI). A visible/near-infrared (Vis/NIR) and short-wave infrared (SWIR) HSI system were used to acquire hyperspectral images for normal and heat stress-exposed plants, showing their susceptibility (Chunpoong) and resistibility (Sunmyoung and Sunil). The acquired hyperspectral images were analyzed using the partial least squares-discriminant analysis (PLS-DA) technique, combining the variable importance in projection and successive projection algorithm methods. The correlation of each group was verified using linear discriminant analysis. The developed models showed 12 bands over 79.2% accuracy in Vis/NIR and 18 bands with over 98.9% accuracy at SWIR in validation data. The constructed beta-coefficient allowed the observation of the key wavebands and peaks linked to the chlorophyll, nitrogen, fatty acid, sugar and protein content regions, which differentiated normal and stressed plants. This result shows that the HSI with the PLS-DA technique significantly differentiated between the heat-stressed susceptibility and resistibility of ginseng plants with high accuracy.
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Panax , Análise Discriminante , Resposta ao Choque Térmico , Humanos , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
The objectives of this research were to investigate (a) what was the most effective infusion rate of remifentanil and (b) the degree to which sympathomimetic effects were involved with cardiovascular stimulation by using a power spectral analysis of heart rate variability (HRV). A total of 63 healthy individuals scheduled for sagittal split ramus osteotomy were enrolled and randomly allocated to 1 of 3 groups: remifentanil infusion rate of 0.1, 0.2, or 0.4 µg/kg/min. Anesthesia was maintained with remifentanil and propofol. Before the surgical procedure, 2% lidocaine containing 12.5 µg/mL epinephrine was administered in the surgical field for local anesthesia. Systolic blood pressure (SBP), heart rate (HR), low-frequency (LF) and high-frequency (HF) components in HRV power spectral analysis, and the LF/HF ratio were analyzed. Increases in SBP and HR were observed after local anesthesia in all 3 groups, but no significant differences were observed between the groups. Remifentanil infusion at 0.1 µg/kg/min may be appropriate to minimize cardiovascular stimulation caused by exogenous epinephrine from local anesthesia. Although a rise in the LF/HF ratio was observed after local anesthesia in all groups, no relationship was observed between the cardiovascular changes and the increase in LF/HF ratio. This suggests that sympathomimetic effects are involved to a lesser extent with the cardiovascular stimulation caused by exogenous epinephrine.