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1.
PLoS Biol ; 20(5): e3001648, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35639773

RESUMO

The continued spread of drug-resistant tuberculosis is one of the most pressing and complex challenges facing tuberculosis management worldwide. Therefore, developing a new class of drugs is necessary and urgently needed to cope with the increasing threat of drug-resistant tuberculosis. This study aims to discover a potential new class of tuberculosis drug candidates different from existing tuberculosis drugs. By screening a library of compounds, methyl (S)-1-((3-alkoxy-6,7-dimethoxyphenanthren-9-yl)methyl)-5-oxopyrrolidine-2-carboxylate (PP) derivatives with antitubercular activity were discovered. MIC ranges for PP1S, PP2S, and PP3S against clinically isolated drug-resistant Mycobacterium tuberculosis strains were 0.78 to 3.13, 0.19 to 1.56, and 0.78 to 6.25 µg/ml, respectively. PPs demonstrated antitubercular activities in macrophage and tuberculosis mouse models, showing no detectable toxicity in all assays tested. PPs specifically inhibited M. tuberculosis without significantly changing the intestinal microbiome in mice. Mutants selected in vitro suggest that the drug targets the PE-PGRS57, which has been found only in the genomes of the M. tuberculosis complex, highlighting the specificity and safety potency of this compound. As PPs show an excellent safety profile and highly selective toxicity specific to M. tuberculosis, PPs are considered a promising new candidate for the treatment of drug-resistant tuberculosis while maintaining microbiome homeostasis.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Camundongos , Tuberculose/tratamento farmacológico
2.
J Virol ; 97(12): e0173723, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38051260

RESUMO

IMPORTANCE: Viruses are constantly evolving to promote propagation in the host. Here, we show that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes host RAD51 for replication. Silencing of RAD51 impaired SARS-CoV-2 propagation. Viral RNA colocalized with RAD51 in the cytoplasm of SARS-CoV-2-infected cells, suggesting that both viral RNA and RAD51 may form a replication complex. We, therefore, evaluated RAD51 inhibitors as possible therapeutic agents against SARS-CoV-2. Indeed, RAD51 inhibitors exerted antiviral activities against not only Wuhan but also variants of SARS-CoV-2. Molecular docking model shows that RAD51 inhibitors impede SARS-CoV-2 propagation by interfering with dimerization of RAD51. These data suggest that RAD51 may represent a novel host-based drug target for coronavirus disease 2019 treatment.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/metabolismo , COVID-19/virologia , Simulação de Acoplamento Molecular , Rad51 Recombinase/antagonistas & inibidores , Rad51 Recombinase/metabolismo , RNA Viral , SARS-CoV-2/fisiologia , Interações Hospedeiro-Patógeno
3.
Skin Res Technol ; 30(6): e13788, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38881052

RESUMO

PURPOSE: This study aimed to develop a novel exfoliating material with high efficacy and low irritation by synthesizing the Mandelic acid_Carnitine ion pairing complex (M_C complex) and evaluating its exfoliating properties. Additionally, the study assessed the skin improvement effects of the M_C complex through clinical evaluations. METHODS: The M_C complex was synthesized in a 1:1 molar ratio of Mandelic acid and Carnitine. Structural characterization was performed using dynamic light scattering and Fourier-transform infrared spectroscopy. Exfoliating efficacy was evaluated on porcine skin, and clinical assessments were conducted on human subjects to measure various skin improvement parameters. RESULTS: The formation of the M_C complex was confirmed through particle size analysis, zeta-potential measurements, and FT-IR spectroscopy. The M_C complex demonstrated superior exfoliating efficacy compared to Mandelic acid alone, especially at pH 4.5. Clinical evaluations showed significant improvements in blackheads, whiteheads, pore volume, depth, density, count, and affected area, as well as skin texture. No adverse reactions were observed. CONCLUSION: The M_C complex exhibits high exfoliating efficacy and minimal irritation, making it a promising cosmetic ingredient for improving skin health. These findings support its potential as a low-irritation exfoliating material under mildly acidic conditions, contributing to overall skin health enhancement.


Assuntos
Carnitina , Cosméticos , Ácidos Mandélicos , Ácidos Mandélicos/química , Ácidos Mandélicos/farmacologia , Humanos , Carnitina/farmacologia , Carnitina/química , Animais , Suínos , Cosméticos/farmacologia , Cosméticos/química , Feminino , Adulto , Pele/efeitos dos fármacos , Pele/química , Masculino , Pessoa de Meia-Idade , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Aging Ment Health ; 28(3): 473-481, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37655598

RESUMO

OBJECTIVES: Disparities impacting dementia health care exist in racial/ethnic minority groups, including Asian Americans, an understudied population in Alzheimer's disease and related dementias. The qualitative study explored caregiving experiences and potential cultural influences among Asian Indian, Chinese, Korean, and Vietnamese family care partners of persons living with dementia. METHODS: We conducted focus groups and individual interviews with 32 care partners from these four Asian subgroups using Zoom, WeChat, or telephone. RESULTS: Four themes emerged from the data: (1) Family obligations influencing caregiving decisions; (2) Evolving challenges related to dementia caregiving; (3) Caregiving burdens/negative impacts from caregiving (relationship burdens and emotional distress); and (4) Coping with their situation in their own ways (cognitive, behavioral, and social strategies).Conclusion: Cultural values (e.g. familism or filial piety) played a significant role in caregiving decisions and experiences. There was a need to raise public awareness of dementia and create culturally and linguistically appropriate training programs for this population.


Assuntos
Doença de Alzheimer , Asiático , Cuidadores , Humanos , Cuidadores/psicologia , Etnicidade , Grupos Minoritários
5.
Nano Lett ; 23(14): 6360-6368, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37409775

RESUMO

Vertical two-terminal synaptic devices based on resistive switching have shown great potential for emulating biological signal processing and implementing artificial intelligence learning circuitries. To mimic heterosynaptic behaviors in vertical two-terminal synaptic devices, an additional terminal is required for neuromodulator activity. However, adding an extra terminal, such as a gate of the field-effect transistor, may lead to low scalability. In this study, a vertical two-terminal Pt/bilayer Sr1.8Ag0.2Nb3O10 (SANO) nanosheet/Nb:SrTiO3 (Nb:STO) device emulates heterosynaptic plasticity by controlling the number of trap sites in the SANO nanosheet via modulation of the tunneling current. Similar to biological neuromodulation, we modulated the synaptic plasticity, pulsed pair facilitation, and cutoff frequency of a simple two-terminal device. Therefore, our synaptic device can add high-level learning such as associative learning to a neuromorphic system with a simple cross-bar array structure.

6.
Small ; 19(28): e2300526, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37010008

RESUMO

Polymer-based nanocomposites are desirable materials for next-generation dielectric capacitors. 2D dielectric nanosheets have received significant attention as a filler. However, randomly spreading the 2D filler causes residual stresses and agglomerated defect sites in the polymer matrix, which leads to the growth of an electric tree, resulting in a more premature breakdown than expected. Therefore, realizing a well-aligned 2D nanosheet layer with a small amount is a key challenge; it can inhibit the growth of conduction paths without degrading the performance of the material. Here, an ultrathin Sr1.8 Bi0.2 Nb3 O10 (SBNO) nanosheet filler is added as a layer into poly(vinylidene fluoride) (PVDF) films via the Langmuir-Blodgett method. The structural properties, breakdown strength, and energy storage capacity of a PVDF and multilayer PVDF/SBNO/PVDF composites as a function of the thickness-controlled SBNO layer are examined. The seven-layered (only 14 nm) SBNO nanosheets thin film can sufficiently prevent the electrical path in the PVDF/SBNO/PVDF composite and shows a high energy density of 12.8 J cm-3 at 508 MV m-1 , which is significantly higher than that of the bare PVDF film (9.2 J cm-3 at 439 MV m-1 ). At present, this composite has the highest energy density among the polymer-based nanocomposites under the filler of thin thickness.

7.
J Pediatr ; 262: 113620, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37473993

RESUMO

OBJECTIVE: To evaluate factors influencing the diagnostic yield of comprehensive gene panel testing (CGPT) for hearing loss (HL) in children and to understand the characteristics of undiagnosed probands. STUDY DESIGN: This was a retrospective cohort study of 474 probands with childhood-onset HL who underwent CGPT between 2016 and 2020 at a single center. Main outcomes and measures included the association between clinical variables and diagnostic yield and the genetic and clinical characteristics of undiagnosed probands. RESULTS: The overall diagnostic yield was 44% (209/474) with causative variants involving 41 genes. While the diagnostic yield was high in the probands with congenital, bilateral, and severe HL, it was low in those with unilateral, noncongenital, or mild HL; cochlear nerve deficiency; preterm birth; neonatal intensive care unit admittance; certain ancestry; and developmental delay. Follow-up studies on 49 probands with initially inconclusive CGPT results changed the diagnostic status to likely positive or negative outcomes in 39 of them (80%). Reflex to exome sequencing on 128 undiagnosed probands by CGPT revealed diagnostic findings in 8 individuals, 5 of whom had developmental delays. The remaining 255 probands were undiagnosed, with 173 (173/255) having only a single variant in the gene(s) associated with autosomal recessive HL and 28% (48/173) having a matched phenotype. CONCLUSION: CGPT efficiently identifies the genetic etiologies of HL in children. CGPT-undiagnosed probands may benefit from follow-up studies or expanded testing.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Nascimento Prematuro , Feminino , Humanos , Criança , Recém-Nascido , Estudos Retrospectivos , Nascimento Prematuro/genética , Perda Auditiva/diagnóstico , Perda Auditiva/genética , Surdez/genética , Fenótipo , Perda Auditiva Neurossensorial/diagnóstico , Testes Genéticos/métodos
8.
J Comput Aided Mol Des ; 37(9): 453-461, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37452977

RESUMO

African swine fever virus (ASFV), an extremely contagious virus with high mortality rates, causes severe hemorrhagic viral disease in both domestic and wild pigs. Fortunately, ASFV cannot be transmitted from pigs to humans. However, ongoing ASFV outbreaks could have severe economic consequences for global food security. Although ASFV was discovered several years ago, no vaccines or treatments are commercially available yet; therefore, the identification of new anti-ASFV drugs is urgently warranted. Using molecular docking and machine learning, we have previously identified pentagastrin, cangrelor, and fostamatinib as potential antiviral drugs against ASFV. Here, using machine learning combined with docking simulations, we identified natural products with a high affinity for AsfvPolX proteins. We selected five natural products (NPs) that are located close in chemical space to the six known natural flavonoids that possess anti-ASFV activity. Polygalic acid markedly reduced AsfvPolX polymerase activity in a dose-dependent manner. We propose an efficient protocol for identifying NPs as potential antiviral drugs by identifying chemical spaces containing high-affinity binders against ASFV in NP databases.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Humanos , Suínos , Animais , Febre Suína Africana/prevenção & controle , Simulação de Acoplamento Molecular , Proteínas Virais , Antivirais/farmacologia , Técnicas In Vitro , Aprendizado de Máquina
9.
Environ Sci Technol ; 57(49): 20605-20614, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38038997

RESUMO

Methane (CH4) is the second most important greenhouse gas, 27 times as potent as CO2 and responsible for >30% of the current anthropogenic warming. Globally, more than half of CH4 is produced microbially through methanogenesis. Pyrogenic black carbon possesses a considerable electron storage capacity (ESC) and can be an electron donor or acceptor for abiotic and microbial redox transformation. Using wood-derived biochar as a model black carbon, we demonstrated that air-oxidized black carbon served as an electron acceptor to support anaerobic oxidation of organic substrates, thereby suppressing CH4 production. Black carbon-respiring bacteria were immediately active and outcompeted methanogens. Significant CH4 did not form until the bioavailable electron-accepting capacity of the biochar was exhausted. An experiment with labeled acetate (13CH3COO-) yielded 1:1 13CH4 and 12CO2 without biochar and predominantly 13CO2 with biochar, indicating that biochar enabled anaerobic acetate oxidation at the expense of methanogenesis. Methanogens were enriched following acetate fermentation but only in the absence of biochar. The electron balance shows that approximately half (∼2.4 mmol/g) of biochar's ESC was utilized by the culture, corresponding to the portion of the ESC > +0.173 V (vs SHE). These results provide a mechanistic basis for quantifying the climate impact of black carbon and developing ESC-based applications to reduce CH4 emissions from biogenic sources.


Assuntos
Dióxido de Carbono , Elétrons , Carvão Vegetal , Oxidantes , Metano , Acetatos , Solo
10.
Sensors (Basel) ; 23(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37177494

RESUMO

This paper describes a practical method for obtaining the spectra of lights emitted by a fluor in a liquid scintillator (LS) using a digital camera. The emission wavelength results obtained using a digital image were compared with those obtained using a fluorescence spectrophotometer. For general users, conventional spectrophotometers are expensive and difficult to access. Moreover, their experimental measurement setup and processes are highly complicated, and they require considerable care in handling. To overcome these limitations, a feasibility study was performed to obtain the emission spectrum through image analysis. Specifically, the emission spectrum of a fluor dissolved in a liquid scintillator was obtained using digital image analysis. An image processing method was employed to convert the light irradiated during camera exposure into wavelengths. Hue (H) and wavelength (W) are closely related. Thus, we obtained an H-W response curve in the 400~450 nm wavelength region, using a light-emitting diode. Another relevant advantage of the method described in this study is its non-invasiveness in sealed LS samples. Our results showed that this method has the potential to accurately investigate the emission wavelengths of fluor within acceptable uncertainties. We envision the use of this method to perform experiments in chemistry and physics laboratories in the future.

11.
Hum Factors ; 65(8): 1641-1654, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34905985

RESUMO

OBJECTIVE: This study evaluated a standing armrest to provide more acceptable ergonomic guidelines that may reduce the cost of standing computer workstations. BACKGROUND: Of the many advantages of standing workstations, there have been no efforts to minimize the biomechanical cost, such as larger wrist extension and greater forearm muscle activity than sitting. METHOD: Sixteen participants were asked to perform a typing task under a combination of the following factors: (1) desk shape (rectangular and concave); (2) desk height (0, +5, -5 cm from 90° elbow flexion); and (3) monitor height (0, -10 cm from the eyes). During the trials, the trunk kinematics, muscle activation levels, and CoP were recorded. RESULTS: Both arms were further away from the upper body under the concave and +5 desk height than under the normal condition, but significant decreases in the extensor carpi radialis (8.6%), anterior deltoid (28.8%), and L4 paraspinals (5.5%) were observed. Similarly, the wrist extension angle decreased by 10.5° (42%) under this condition, but the posture required a 2.2° (19%) increase in wrist adduction angle. The CoP irregularity was greater under the concave workstation, indicating more complex motion. CONCLUSION: A higher and concave desk can provide an armrest effect while engaged in a standing workstation by reducing the wrist extension and related muscle activation level, but at the cost of a larger wrist adduction angle. APPLICATION: Providing a standing armrest (+5 cm height and concave desk) could reduce the stresses on the upper extremities, but a split keyboard should be considered to minimize wrist adduction.


Assuntos
Posição Ortostática , Extremidade Superior , Humanos , Extremidade Superior/fisiologia , Ergonomia , Postura/fisiologia , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos
12.
Int J Mol Sci ; 24(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37569885

RESUMO

Icariin, a flavonoid abundant in the herb Epimedium, exhibits anti-ferroptotic activity. However, its impact on nonalcoholic steatohepatitis (NASH) development remains unclear. This study aimed to investigate the potential role of icariin in mitigating methionine choline-deficient (MCD) diet-induced NASH in C57BL/6J mice. The results showed that icariin treatment significantly reduced serum alanine aminotrasferase and aspartate aminotransferase activities while improving steatosis, inflammation, ballooning, and fibrosis in the liver tissues of mice fed the MCD diet. These improvements were accompanied by a substantial reduction in the hepatic iron contents and levels of malondialdehyde and 4-hydroxynonenal, as well as an increase in the activities of catalase and superoxide dismutase. Notably, icariin treatment suppressed the hepatic protein levels of ferroptosis markers such as acyl-CoA synthetase long-chain family member 4 and arachidonate 12-lipoxygenase, which were induced by the MCD diet. Furthermore, transmission electron microscopy confirmed the restoration of morphological changes in the mitochondria, a hallmark characteristic of ferroptosis, by icariin. Additionally, icariin treatment significantly increased the protein levels of Nrf2, a cystine/glutamate transporter (xCT), and glutathione peroxidase 4 (GPX4). In conclusion, our study suggests that icariin has the potential to attenuate NASH, possibly by suppressing ferroptosis via the Nrf2-xCT/GPX4 pathway.


Assuntos
Deficiência de Colina , Ferroptose , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Colina/metabolismo , Metionina/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Deficiência de Colina/complicações , Deficiência de Colina/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Flavonoides/farmacologia , Flavonoides/metabolismo , Racemetionina/metabolismo , Dieta , Suplementos Nutricionais
13.
Eur J Dent Educ ; 27(4): 1031-1039, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36655941

RESUMO

INTRODUCTION: A software program was developed to provide visual, guided feedback to students for access cavity preparations in preclinical learning. The specific aim of the study was to investigate students' overall experiences with the new learning method and compare their experiences with traditional teaching. MATERIALS AND METHODS: A workflow based on freely available software was designed to interactively register three-dimensional models of molars with access cavities, and to metrically compare these to instructor-prepared standard cavities. Third-year students practicing molar endodontics access cavity preparation in the preclinical course were then surveyed. A total of 44/79 students completed self-administered questionnaires prior and after the use of the feedback software to gauge their learning experience. RESULTS: The results of the post-training questionnaire illustrated that all surveyed students agreed/strongly agreed that the software assisted their learning in access cavity preparation. In addition, 86 and 89%, respectively, of students agreed that the use of the software improved their skills of access cavity preparation and felt more confident about their access cavity preparation skills after using the software package, 3D Dental Align. DISCUSSION: The presented software solution permitted setting and comparing access cavity preparations by students against a standard access prepared by an instructor. The process of data acquisition and registration was fast and straightforward. Student feedback was very positive and suggested the integration of this type of experiential learning into the preclinical curriculum. CONCLUSION: This feasibility study demonstrated the utility of the new technology to assist dental students' access cavity preparation learning.


Assuntos
Avaliação Educacional , Endodontia , Humanos , Retroalimentação , Avaliação Educacional/métodos , Estudantes de Odontologia , Educação em Odontologia/métodos , Software , Endodontia/educação
14.
Clin Oral Investig ; 26(2): 2133-2142, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34591181

RESUMO

OBJECTIVES: The objectives of this study were to develop a novel bleaching material containing hydrated calcium silicate (hCS) particles and investigate the effects of hCS on the bleaching efficacy, microhardness, and surface morphology of bovine enamel. MATERIALS AND METHODS: To prepare the hCS particles, white Portland cement was mixed with distilled water and ground into a fine powder. The particles in various proportions were then mixed with 35% hydrogen peroxide solution (HP), while HP without hCS was used as a control (HP), and teeth whitening gel was used as a commercial control (CC). Following the thrice application of experimental and control solutions on the discolored bovine enamel surface for 15 min, color change (n = 10), microhardness (n = 10), and micromorphology (n = 2) of the enamel surface were analyzed. RESULTS: The Δ E* of the enamel surface treated with the experimental solution containing hCS was significantly higher than that of the CC, but there were no significant differences between the different hCS contents. The experimental solution containing hCS reduced the percentage of microhardness loss on the enamel surface, and the percentage of microhardness loss significantly decreased as the content of hCS increased (p < 0.05). The erosion pattern was only observed on enamel surfaces treated with HP and CC. CONCLUSIONS: This study suggests that HP containing hCS is effective in bleaching efficacy. In addition, hCS could also minimize the microhardness loss of tooth structure caused by HP and maintain enamel surface morphology. CLINICAL RELEVANCE: This novel bleaching material is promising for inhibiting demineralization and promoting the remineralization of teeth during bleaching treatment in dental clinics.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Compostos de Cálcio , Bovinos , Esmalte Dentário , Dureza , Peróxido de Hidrogênio/farmacologia , Silicatos , Clareadores Dentários/farmacologia
15.
Sensors (Basel) ; 22(9)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35590931

RESUMO

Motion capture systems are crucial in developing multi-quadrotor systems due to their ability to provide fast and accurate ground truth measurements for tracking and control. This paper presents the implementation details and experimental validation of a relatively low-cost motion-capture system for multi-quadrotor motion planning using an event camera. The real-time, multi-quadrotor detection and tracking tasks are performed using a deep learning network You-Only-Look-Once (YOLOv5) and a k-dimensional (k-d) tree, respectively. An optimization-based decentralized motion planning algorithm is implemented to demonstrate the effectiveness of this motion capture system. Extensive experimental evaluations were performed to (1) compare the performance of four deep-learning algorithms for high-speed multi-quadrotor detection on event-based data, (2) study precision, recall, and F1 scores as functions of lighting conditions and camera motion, and (3) investigate the scalability of this system as a function of the number of quadrotors flying in the arena. Comparative analysis of the deep learning algorithms on a consumer-grade GPU demonstrates a 4.8× to 12× sampling/inference rate advantage that YOLOv5 provides over representative one- and two-stage detectors and a 1.14× advantage over YOLOv4. In terms of precision and recall, YOLOv5 performed 15% to 18% and 27% to 41% better than representative state-of-the-art deep learning networks. Graceful detection and tracking performance degradation was observed in the face of progressively darker ambient light conditions. Despite severe camera motion, YOLOv5 precision and recall values of 94% and 98% were achieved, respectively. Finally, experiments involving up to six indoor quadrotors demonstrated the scalability of this approach. This paper also presents the first open-source event camera dataset in the literature, featuring over 10,000 fully annotated images of multiple quadrotors operating in indoor and outdoor environments.


Assuntos
Algoritmos , Iluminação , Movimento (Física)
16.
Sensors (Basel) ; 22(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35808370

RESUMO

We synthesized an alcohol-based liquid scintillator (AbLS), and we implemented an auxiliary monitoring system with short calibration intervals using AbLS for particle therapy. The commercial liquid scintillator used in previous studies did not allow the user to control the chemical ratio and its composition. In our study, the chemical ratio of AbLS was freely controlled by simultaneously mixing water and alcohol. To make an equivalent substance to the human body, 2-ethoxyethanol was used. There was no significant difference between AbLS and water in areal density. As an application of AbLS, the range was measured with AbLS using an electron beam in an image analysis that combined AbLS and a digital phone camera. Given a range-energy relationship for the electron expressed as areal density, the electron beam range (cm) in water can be easily estimated. To date, no literature report for the direct comparison of a pixel image analysis and Monte Carlo (MC) simulation has been published. Furthermore, optical tomography of the inverse problem was performed with AbLS and a mobile phone camera. Analyses of optical tomography images provide deeper insight into Radon transformation. In addition, the human phantom, which is difficult to compose with semiconductor diodes, was easily implemented as an image acquisition and analysis system.


Assuntos
Elétrons , Processamento de Imagem Assistida por Computador , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Água
17.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080877

RESUMO

We introduced a digital photo image analysis in color space to estimate the spectrum of fluor components dissolved in a liquid scintillator sample through the hue and wavelength relationship. Complementary metal oxide semiconductor (CMOS) image sensors with Bayer color filter array (CFA) technology in the digital camera were used to reconstruct and decode color images. Hue and wavelength are closely related. To date, no literature has reported the hue and wavelength relationship measurements, especially for blue or close to the UV region. The non-linear hue and wavelength relationship in the blue region was investigated using a light emitting diode source. We focused on this wavelength region, because the maximum quantum efficiency of the bi-alkali photomultiplier tube (PMT) is around 430 nm. It is necessary to have a good understanding of this wavelength region in PMT-based experiments. The CMOS Bayer CFA approach was sufficient to estimate the fluor emission spectrum in the liquid scintillator sample without using an expensive spectrophotometer.

18.
Sensors (Basel) ; 22(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36502198

RESUMO

In this study, a non-linear hue-wavelength (H-W) curve was investigated from 400 to 650 nm. To date, no study has reported on H-W relationship measurements, especially down to the 400 nm region. A digital camera mounted with complementary metal oxide semiconductor (CMOS) image sensors was used. The obtained digital images of the sample were based on an RGB-based imaging analysis rather than multispectral imaging or hyperspectral imaging. In this study, we focused on the raw image to reconstruct the H-W curve. In addition, several factors affecting the digital image, such as exposure time or international organization for standardization (ISO), were investigated. In addition, cross check of the H-W response using laser was performed. We expect that our method will be useful as an auxiliary method in the future for obtaining the fluor emission wavelength information.


Assuntos
Processamento de Imagem Assistida por Computador , Semicondutores , Processamento de Imagem Assistida por Computador/métodos , Óxidos
19.
Sensors (Basel) ; 22(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36560324

RESUMO

The quality of heart rate (HR) measurements extracted from human photoplethysmography (PPG) signals are known to deteriorate under appreciable human motion. Auxiliary signals, such as accelerometer readings, are usually employed to detect and suppress motion artifacts. A 2019 study by Yifan Zhang and his coinvestigatorsused the noise components extracted from an infrared PPG signal to denoise a green PPG signal from which HR was extracted. Until now, this approach was only tested on "micro-motion" such as finger tapping. In this study, we extend this technique to allow accurate calculation of HR under high-intensity full-body repetitive "macro-motion". Our Dual Wavelength (DWL) framework was tested on PPG data collected from 14 human participants while running on a treadmill. The DWL method showed the following attributes: (1) it performed well under high-intensity full-body repetitive "macro-motion", exhibiting high accuracy in the presence of motion artifacts (as compared to the leading accelerometer-dependent HR calculation techniques TROIKA and JOSS); (2) it used only PPG signals; auxiliary signals such as accelerometer signals were not needed; and (3) it was computationally efficient, hence implementable in wearable devices. DWL yielded a Mean Absolute Error (MAE) of 1.22|0.57 BPM, Mean Absolute Error Percentage (MAEP) of 0.95|0.38%, and performance index (PI) (which is the frequency, in percent, of obtaining an HR estimate that is within ±5 BPM of the HR ground truth) of 95.88|4.9%. Moreover, DWL yielded a short computation period of 3.0|0.3 s to process a 360-second-long run.


Assuntos
Algoritmos , Corrida , Humanos , Frequência Cardíaca/fisiologia , Fotopletismografia/métodos , Processamento de Sinais Assistido por Computador , Artefatos
20.
Int J Mol Sci ; 23(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35887165

RESUMO

BACKGROUND: Atrophy of the vocal folds and the accompanying glottic insufficiency affect the quality of life. Although growth factors have been used to treat muscle atrophy, their effectiveness is limited by their short half-life. METHODS: In total, 15 rabbits and 24 rats were used for the study. The right recurrent laryngeal nerves of all animals were transected. One month following nerve transection, PBS (PBS group), rHGF (HGF group), or a c-Met agonistic antibody (c-Met group) was injected into the paralyzed vocal folds. The larynges of the rabbits were harvested from each group for histologic examination and subjected to PCR analysis. RESULTS: Cross-sectional areas (CSAs) of thyroarytenoid muscles were evaluated. The c-Met group had increased CSAs compared to the PBS and HGF groups, but there were no significant differences compared to normal controls. The expression levels of myogenesis-related genes were evaluated three weeks after the injection. The expression levels of myosin heavy chain IIa were significantly increased in the PBS group, while the expression levels of MyoD were increased in the c-Met group. CONCLUSIONS: The c-Met agonistic antibody showed promise for promoting muscle regeneration in a vocal fold palsy model.


Assuntos
Paralisia das Pregas Vocais , Prega Vocal , Animais , Músculos Laríngeos , Atrofia Muscular/metabolismo , Qualidade de Vida , Coelhos , Ratos , Paralisia das Pregas Vocais/metabolismo , Paralisia das Pregas Vocais/patologia , Paralisia das Pregas Vocais/terapia , Prega Vocal/metabolismo
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