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1.
Korean J Radiol ; 25(3): 224-242, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38413108

RESUMO

The emergence of Chat Generative Pre-trained Transformer (ChatGPT), a chatbot developed by OpenAI, has garnered interest in the application of generative artificial intelligence (AI) models in the medical field. This review summarizes different generative AI models and their potential applications in the field of medicine and explores the evolving landscape of Generative Adversarial Networks and diffusion models since the introduction of generative AI models. These models have made valuable contributions to the field of radiology. Furthermore, this review also explores the significance of synthetic data in addressing privacy concerns and augmenting data diversity and quality within the medical domain, in addition to emphasizing the role of inversion in the investigation of generative models and outlining an approach to replicate this process. We provide an overview of Large Language Models, such as GPTs and bidirectional encoder representations (BERTs), that focus on prominent representatives and discuss recent initiatives involving language-vision models in radiology, including innovative large language and vision assistant for biomedicine (LLaVa-Med), to illustrate their practical application. This comprehensive review offers insights into the wide-ranging applications of generative AI models in clinical research and emphasizes their transformative potential.


Assuntos
Inteligência Artificial , Radiologia , Humanos , Diagnóstico por Imagem , Software , Idioma
2.
J Biomol Struct Dyn ; 42(6): 2793-2808, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37184132

RESUMO

The chromone derivatives are playing a prominent role in many plant cycles, for instance, the regulation of growth, stimulation of oxygen uptake in plants, and essential food constituents with valuable pro-health properties. Determination of the antioxidant activity of these compounds is an interesting approach to drug design and development. The antioxidant activity of the novel fifteen chromone compounds was estimated by using a spectrophotometric Dichloro-5,6-dicyano 1,4-benzoquinone (DDQ) assay method and the mechanism of antioxidant activity was discussed based on the Density functional theory (DFT) calculations. The compounds showed significant antioxidant activity which was correlated to their molecular structure by considering various molecular descriptors. Further, by using regression analysis QSAR-modeled equation was proposed and it has shown a high correlation coefficient value (0.946. We perform molecular docking and molecular dynamics simulations against the cyclooxygenase (COX2) enzyme to investigate the molecule's anti-inflammatory activity and stability of protein-ligand complexes. Molecular docking and dynamics simulations revealed the compounds B3 and B8 were interacting with essential residues TYR385, HIS386, ASN382, TRP387, and HIS388 in the binding site that were crucial for optimizing heme and the resultant peroxidase and cyclooxygenase activities. The root mean square displacement and root mean square fluctuation plots revealed the stability of the B3-COX2 and B8-COX2 complexes. Based on our results, B3 and B8 compounds are considered as best antioxidants as well as COX2 inhibitors.Communicated by Ramaswamy H. Sarma.


Assuntos
Antioxidantes , Simulação de Dinâmica Molecular , Simulação de Acoplamento Molecular , Antioxidantes/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2 , Relação Quantitativa Estrutura-Atividade
3.
Langmuir ; 39(48): 17471-17479, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37984860

RESUMO

Tuning the wettability of a flat surface by introducing an array of microscale pillars finds wide applications, especially in engineering a superhydrophobic surface. The wettability of such a pillared surface is quantified by the contact angle (CA) of a water droplet. It is desired to know the CA prior to construction of pillars, in order to obviate the trial-and-errors in experimenting with many different topographies. Given an accurate theoretical prediction of CA has been elusive, we propose a convolutional neural network (CNN) model of CA for a surface patterned with rectangular or cylindrical pillars. By employing a three-dimensional descriptor of the surface topography, the present CNN model can predict experimental CAs within errors comparable to the uncertainties in measuring CAs.

4.
Molecules ; 28(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37298990

RESUMO

By using molecular dynamics simulation, we investigate the wettability of a surface texturized with a periodic array of hierarchical pillars. By varying the height and spacing of the minor pillars on top of major pillars, we investigate the wetting transition from the Cassie-Baxter (CB) to Wenzel (WZ) states. We uncover the molecular structures and free energies of the transition and meta-stable states existing between the CB and WZ states. The relatively tall and dense minor pillars greatly enhance the hydrophobicity of a pillared surface, in that, the CB-to-WZ transition requires an increased activation energy and the contact angle of a water droplet on such a surface is significantly larger.


Assuntos
Molhabilidade , Propriedades de Superfície , Interações Hidrofóbicas e Hidrofílicas , Simulação por Computador
5.
Korean J Med Educ ; 34(4): 259-271, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36464897

RESUMO

PURPOSE: This study analyzed the current status of and correlations between Korean medical students' experiences and perspectives surrounding patient-centered medical education (PCME). METHODS: A structured PCME questionnaire composed of three categories, understanding patients within social and cultural contexts, understanding patients' individual health contexts through communication, and placement of patients at the center of medical education, was used. The students were stratified into pre-medical (Pre-med), medical (Med), and policlinic (PK) groups because of curriculum differences by grade. The χ2 test was applied to analyze the association between students' experiences with and perspectives on PCME. A Cramer's V of 0.200 was considered a large effect size for any association between experiences with and perspectives on PCME. RESULTS: Among the respondents, 50.6% answered that they did not know about patient-centered medicine before the survey. With increasing school years went up from Pre-med to PK, fewer students agreed that PCME should be added to pre-clinical medicine curricula (p<0.001), that patients should be in the center throughout medical education (p=0.011), and that patients' personal histories, values, and objectives are important PCME (p=0.001). Students who said they learned PCME for each category were more likely to consider PCME important (Cramer's V was 0.219 and 0.271 for "with," and "for the patients" respectively, p<0.001 for "about/with/for the patients"). Students in all groups chose clinical practice as the best method for PCME (p=0.021). Med group chose the lectures as the most effective tool to learn about the importance of communication (p<0.001). CONCLUSION: Students who experienced PCME were likely to perceive PCME as important and it showed that experiences of PCME had positive effects on PCME perceptions. Despite students' preferences for clinical practice as the best method for PCME, PK reported that they did not learn PCME, and regarded PCME as less important compared to students at earlier stages of their medical education. Therefore, more intensive and holistic PCME curricula rather than only clinical practice exposure may be necessary.


Assuntos
Educação Médica , Estudantes de Medicina , Humanos , República da Coreia , Currículo , Assistência Centrada no Paciente
6.
Artigo em Inglês | MEDLINE | ID: mdl-35162067

RESUMO

Non-alcoholic fatty liver disease (NAFLD) and serum uric acid (SUA) levels are risk factors for developing cardiovascular disease (CVD). Additionally, previous studies have suggested that high SUA levels increase the risk of having NAFLD. However, no study has investigated the relationship between SUA and CVD risk in NAFLD. This study analyzed the relationship between SUA and CVD in NAFLD. Data for this study used the 2016-2018 Korean National Health and Nutrition Examination Survey, which represents the Korean population. A total of 11,160 NAFLD patients were included. Participants with hepatic steatosis index ≥ 30 were considered to have NAFLD. Ten-year CVD risk was estimated using an integer-based Framingham risk score. Estimated 10-year CVD risk ≥ 20% was considered high risk. Multiple logistic regression was conducted to calculate the odds ratios (ORs) associated with SUA level and CVD risk. High CVD risk OR increases by 1.31 (95% CI 1.26-1.37) times per 1 mg/dL of SUA. After adjustment, SUA still had an increased risk (OR 1.44; 95% CI 1.38-1.51) of CVD. Compared with the lowest SUA quartile group, the highest quartile group showed a significantly higher risk of having CVD before (OR 2.76; 95% CI 2.34-3.25) and after (OR 4.01; 95% CI 3.37-4.78) adjustment. SUA is independently associated with CVS risk in NAFLD.


Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Doenças Cardiovasculares/epidemiologia , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Inquéritos Nutricionais , Fatores de Risco , Ácido Úrico
7.
Nutrients ; 13(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34836040

RESUMO

We investigated the association between dietary habits, evaluated using the modified Mini Dietary Assessment Index for Koreans (MDA), and lipid control among patients aged ≥20 years who had used pravastatin for dyslipidemia for 6 months. Participants were administered questionnaires regarding sociodemographic characteristics and lifestyle factors. Odds ratios and 95% confidence intervals for the control of low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and total cholesterol (TC) at 6 months for each category of the modified MDA items were calculated through multivariate logistic regression analysis. The odds for controlled LDL-C was higher among those who consumed cholesterol-rich foods <1 time/week (3.27, 1.25-8.57) than for those who did so ≥4 times/week. The odds for controlled TG was higher among those who always consumed dairy products (2.96, 1.36-6.44), ate protein-rich foods three times/day (2.94, 1.06-8.10), and had a regular eating schedule (3.02, 1.30-7.00) than among those who did not have any of these. The odds for controlled TC was higher among those with a regular eating schedule (3.47, 1.55-7.76) than among their counterparts. Patients with dyslipidemia should consume less cholesterols, consume more dairy and protein-rich foods, and follow a regular eating schedule to control lipid profiles.


Assuntos
Dieta/estatística & dados numéricos , Dislipidemias/sangue , Comportamento Alimentar/fisiologia , Lipídeos/sangue , Pravastatina/uso terapêutico , Idoso , Colesterol/sangue , LDL-Colesterol/sangue , Dieta/efeitos adversos , Dislipidemias/tratamento farmacológico , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , República da Coreia , Inquéritos e Questionários , Triglicerídeos/sangue
8.
Langmuir ; 37(31): 9336-9345, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34314174

RESUMO

Using all-atom molecular dynamics simulation, we investigated the wettability of a surface texturized with nanoscale pillars of domed, rectangular, or cylindrical shapes. The dewetted and wetted states of the gaps between the pillars were related to the Cassie-Baxter (CB) and Wenzel (WZ) states of a macroscopic water droplet resting on top of the pillars. We uncovered the structures and free energies of the intermediate states existing between the CB and WZ states. The contact line of the liquid-vapor-solid interface could not be depinned for the domed pillars due to their smooth curvatures unlike for the rectangular or cylindrical pillars. The liquid symmetrically penetrated down into the gap between the domed pillars by a liquid-vapor interface shape like a paraboloid, while the penetration for the rectangular or cylindrical pillars was often asymmetrical, giving a half-tubular liquid-vapor interface.

9.
Sensors (Basel) ; 21(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467611

RESUMO

It is important to operate devices with control panels and touch screens assisted by haptic feedback in mobile environments such as driving automobiles and electric power wheelchairs. A lot of consideration is needed to give accurate haptic feedback, especially, presenting clear touch feedback to the elderly and people with reduced sensation is a very critical issue from healthcare and safety perspectives. In this study, we aimed to identify the perceptual characteristics for the frequency and direction of haptic vibration on the touch screen with vehicle-driving vibration and to propose an efficient haptic system based on these characteristics. As a result, we demonstrated that the detection threshold shift decreased at frequencies above 210 Hz due to the contact pressure during active touch, but the detection threshold shift increased at below 210 Hz. We found that the detection thresholds were 0.30-0.45 gpeak with similar sensitivity in the 80-270 Hz range. The haptic system implemented by reflecting the experimental results achieved characteristics suitable for use scenarios in automobiles. Ultimately, it could provide practical guidelines for the development of touch screens to give accurate touch feedback in the real-world environment.


Assuntos
Retroalimentação Sensorial , Retroalimentação , Interface Usuário-Computador , Idoso , Desenho de Equipamento , Humanos , Estimulação Física , Vibração
10.
Phys Chem Chem Phys ; 23(2): 1031-1037, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33346266

RESUMO

Mussel foot proteins (MFPs) strongly adhere to both hydrophilic and hydrophobic surfaces under wet conditions. This water-resistant adhesion of MFP is ascribed to catechol (1,2-dihydroxybenzene) which is highly contained in the MFP. Currently, little is known about the molecular details of the underwater adhesion of catechol onto a nonpolar hydrophobic surface. By using the density functional theory, we investigate the adhesion of catechol onto a wet graphite surface. We unveil the molecular geometry and energy in the course of the wet adhesion of catechol. Catechol adheres through π-π stacking with the underlying graphite. The surrounding water molecules further strengthen the adhesion by forming hydrogen bonds with catechol. In addition, a significant charge transfer has been observed from wet graphite to the catechol. Consequently, catechol adheres onto the present hydrophobic surface as strongly as onto a hydrophilic silica surface.

11.
Patient Prefer Adherence ; 14: 2009-2016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122894

RESUMO

BACKGROUND: Factors determining bisphosphonate compliance are not fully understood. We examined fluctuations in oral bisphosphonate dosing intervals to gauge therapeutic compliance in patients with osteoporosis. MATERIALS AND METHODS: Hospital data accruing between 2010 and 2017 were accessed to retrospectively study patients ≥50 years old (N=1873), each prescribed bisphosphonate at initial diagnosis of osteoporosis. The medication possession ratio (MPR), calculated as total days supplied divided by length of follow-up, served to measure therapeutic compliance. We compared MPRs of various prescription patterns (daily, weekly, monthly, and switch [ie, ≥1 change in pattern] groups). We also analyzed the impact of age, sex, fracture history, surgical history, and comorbidities. Multiple regression analysis was ultimately performed, using MPR as a dependent variable. RESULTS: In our cohort (mean follow-up=5.7±2.4 years), once weekly dosing was the most common prescription pattern (1223/1873, 65.3%), as opposed to monthly (366/1873, 19.5%) or daily (164/1873, 8.8%) dosing. A total of 120 patients (6.4%) comprising the switch group changed dosing patterns during the study period. MPR was significantly higher in the switch group (32.8±22.7) than in the other three groups (daily, 21.9±25.9; weekly, 22.7±27.3; monthly, 23.2±27.7). In multiple regression analysis, younger age (P<0.001), female sex (P=0.004), and switching of prescription pattern (decrease or increase frequency) were factors significantly associated with higher MPR, signaling better compliance. CONCLUSION: Better bisphosphonate compliance was associated with physician-modified dosing patterns. We therefore recommend adjustments of prescription intervals in poorly compliant patients requiring long-term treatment.

12.
IEEE Trans Haptics ; 10(3): 371-381, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28114036

RESUMO

This paper presents three methods of input voltage signals that allow low voltage operation of an electrovibration display while preserving the perceptual feel and strength of electrovibration stimuli. The first method uses the amplitude modulation of a high-frequency carrier-signal. The second method uses a dc-offset, and the third method uses a combination of the two methods. The performance of the three methods was evaluated by a physical experiment that measured and analyzed static (dc-component) and dynamic (vibratory component) friction forces and two subsequent psychophysical studies. The physical experiment showed that only the dc -offset method enabled a statistically significant increase in the static friction force between the fingertip and the surface of the electrovibration display. The static friction increase was closely related to the root mean square of input voltage level. In contrast, all of the three methods increased the dynamic friction force significantly, which was deemed to be related to the high frequency effect validated in the previous literature. The first psychophysical study showed that the three proposed methods can significantly reduce the peak-to-peak (p-p) amplitude of an input voltage signal while generating perceptually equally strong electrovibrations to that produced by the conventional method. Using lower p-p voltage has the merits of a simpler electrical circuit and less electromagnetic noise, saving the overall system cost. Further, the perceived intensity of electrovibration was more correlated to the dynamic friction force than the static friction force. The second psychophysical study was a discrimination experiment, and it demonstrated that all the three proposed methods and the conventional method can provide perceptually similar stimuli despite their different signal forms and voltage amplitudes. Our experimental investigation allowed us to conclude that the dc-offset method is the best way to lower the driving voltage of an electrovibration display while providing perceptually equivalent electrovibrations.


Assuntos
Discriminação Psicológica/fisiologia , Fenômenos Eletromagnéticos , Dedos , Fricção , Psicofísica , Percepção do Tato/fisiologia , Vibração , Adulto , Equipamentos e Provisões Elétricas , Feminino , Humanos , Masculino , Adulto Jovem
13.
IEEE Trans Haptics ; 8(4): 492-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26372656

RESUMO

Electrovibration is a type of surface haptics that can modulate lateral forces acting between a fingertip and a touch surface. Electrovibration is fast, consumes little power, and does not involve the use of any mechanical actuators. However, it suffers from problems such as nonuniform perceived intensity due to varying environmental impedances, as well as possible electric shock, which have to be solved for commercialization. In this paper, a current feedback method is proposed to provide uniform intensity of electrovibration, regardless of the varying environmental impedances. The proposed method can also prevent electric shock. To show the effectiveness of the proposed method, a hardware prototype was developed and a user study was conducted. The user study result shows that the proposed current control method can provide significantly more uniform perceived intensity of electrovibration as compared with the conventional voltage control method.


Assuntos
Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Vibração , Impedância Elétrica , Desenho de Equipamento , Retroalimentação , Feminino , Dedos , Humanos , Masculino , Tato , Adulto Jovem
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