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1.
J Cosmet Dermatol ; 22(11): 3159-3167, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37313638

RESUMEN

BACKGROUND: Baumann skin type questionnaire (BSTQ) has been widely used for evaluating skin types in dermatology. However, it requires excessive assessment time and lacks sufficient clinical validation for the Asian population. AIMS: We aimed to establish optimized BSTQ based on dermatological assessment of the Asian population. METHODS: This was a single-center retrospective study, where the patient completed a modified BSTQ and a digital photography examination. The answers to four question groups for evaluating skin properties, including oily versus dry (O-D), sensitive versus resistant (S-R), pigmented versus non-pigmented (P-N), and wrinkled versus tight (W-T) were compared with the measurements. Highly relevant questions are selected using two different strategies and used to determine the threshold level, which was compared with skin-type measurement. RESULTS: In O-D, S-R, P-N, and W-T, 3-5 out of 6, 2-6 out of 9, 3-6 out of 7, and 4-9 out of 11 questions were selected, respectively. As a result, skin type scores from two strategies and measurements showed similar Pearson correlation coefficient values compared to modified BSTQ (for O-D and sebum, 0.236/0.266 vs. 0.232; for O-D and porphyrin, 0.230/0.267 vs. 0.230; for S-R and redness, 0.157/0.175 vs. 0.095; for S-R and porphyrin, 0.061 vs. 0.051; for P-N and melanin pigmentation, 0.156/0.208 vs. 0.150; for W-T and wrinkle, 0.265/0.269 vs. 0.217). CONCLUSION: Two strategies for optimizing BSTQ are proposed and validated for Asian patients. Compared to the BSTQ, our methods show comparable performance with a significantly reduced number of questions.

2.
J Addict Nurs ; 34(1): 8-15, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36857543

RESUMEN

ABSTRACT: The purpose of this study was to explore the determinants of self-reported smoking cessation among out-of-school Korean adolescents who participated in a counselor-visiting smoking cessation program. This retrospective descriptive study analyzed data from the Korea Health Promotion Institute. Participants were enrolled between June 1, 2015, and December 31, 2017, at a regional smoking cessation center in a counselor-visiting smoking cessation program for out-of-school adolescents. Participants consisted of 807 adolescents (70.3% male) with a mean age of 16.9 ± 1.2 years. Multiple logistic regression analysis showed that female gender (OR = 1.54-1.92), cohort year 2016 (OR = 1.69-1.90), smoking more than half a pack a day (OR = 0.44-0.50), strong motivation to quit (OR = 1.44), and number of counseling in person (OR = 1.97-2.10) were statistically significant independent contributors to quitting, based on follow-up assessments at 4 weeks, 12 weeks, and 6 months. This study explored smoking cessation outcomes of a government-driven smoking cessation program that targeted out-of-school adolescents and identified several risk factors that affect a successful outcome. More research is necessary to evaluate the efficacy of such smoking cessation programs for marginalized or understudied populations.


Asunto(s)
Consejeros , Cese del Hábito de Fumar , Adolescente , Femenino , Masculino , Humanos , Estudios Retrospectivos , Factores Sexuales , República de Corea
3.
Sensors (Basel) ; 21(14)2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34300674

RESUMEN

The evolution of the internet has led to the growth of smart application requirements on the go in the vehicular ad hoc network (VANET). VANET enables vehicles to communicate smartly among themselves wirelessly. Increasing usage of wireless technology induces many security vulnerabilities. Therefore, effective security and authentication mechanism is needed to prevent an intruder. However, authentication may breach user privacy such as location or identity. Cryptography-based approach aids in preserving the privacy of the user. However, the existing security models incur communication and key management overhead since they are designed considering a third-party server. To overcome the research issue, this work presents an efficient security model namely secure performance enriched channel allocation (S-PECA) by using commutative RSA. This work further presents the commutative property of the proposed security scheme. Experiments conducted to evaluate the performance of the proposed S-PECA over state-of-the-art models show significant improvement. The outcome shows that S-PECA minimizes collision and maximizes system throughput considering different radio propagation environments.

4.
Magn Reson Med ; 85(3): 1209-1221, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32851659

RESUMEN

PURPOSE: To make clinically feasible whole-brain chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) by enhancing imaging efficiency. METHODS: A novel, whole-brain three-dimensional (3D) steady-state CEST MRI method was introduced by utilizing a time-efficient, fat-suppressed excitation followed by rapid, segmented 3D echo-planar-imaging with incoherent undersampling in k-ω space. Missing signals and CEST-specific spectral images were then jointly estimated directly from incomplete measurements using model-based reconstruction and robust spectral analysis. In vivo studies were performed at 3T both retrospectively (using a fully sampled reference) and prospectively to validate the effectiveness of the proposed method in patients with brain cancer. RESULTS: In retrospective studies, the proposed method exhibits superior accuracies to existing methods in estimating images, z-spectra, and APTw relative to the reference. In prospective patient studies, compared with existing methods, the proposed method is statistically significantly different in contrast-to-noise ratio of the APTw contrast between tumor and normal appearing white matter (NAWM) and amide proton transfer weighted contrast (p < 0.05) while not being significantly different in signal-to-noise ratio in an NAWM region. CONCLUSIONS: We successfully demonstrated that it is feasible to perform whole-brain CEST MRI roughly within 4 minutes for patients with brain cancer. It is expected that the proposed method widens clinical utilities of CEST MRI.


Asunto(s)
Neoplasias Encefálicas , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico por imagen , Humanos , Fantasmas de Imagen , Estudios Prospectivos , Estudios Retrospectivos
5.
IEEE Trans Med Imaging ; 39(2): 283-293, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30762539

RESUMEN

This paper introduces a novel, model-based chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI), in which asymmetric spectra of interest are directly estimated from complete or incomplete measurements by incorporating subspace-based spectral signal decomposition into the measurement model of CEST MRI for a robust z-spectrum analysis. Spectral signals are decomposed into symmetric and asymmetric components. The symmetric component, which varies smoothly, is delineated by the linear superposition of a finite set of vectors in a basis trained from the simulated (Lorentzian) signal vectors augmented with data-driven signal vectors, while the asymmetric component is to be inherently lower than or equal to zero due to saturation transfer phenomena. Spectral decomposition is performed directly on the measured spectral data by solving a constrained optimization problem that employs the linearized spectral decomposition model for the symmetric component and the weighted Frobenius norm regularization for the asymmetric component while utilizing additional spatial sparsity and low-rank priors. The simulations and in vivo experiments were performed to demonstrate the feasibility of the proposed method as a reliable molecular MRI.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Análisis Espectral/métodos , Animales , Encéfalo/diagnóstico por imagen , Simulación por Computador , Masculino , Fantasmas de Imagen , Ratas , Ratas Sprague-Dawley
6.
Sensors (Basel) ; 15(7): 15127-58, 2015 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-26131669

RESUMEN

The commonly unattended and hostile deployments of WSNs and their resource-constrained sensor devices have led to an increasing demand for secure energy-efficient protocols. Routing and data aggregation receive the most attention since they are among the daily network routines. With the awareness of such demand, we found that so far there has been no work that lays out a secure routing protocol as the foundation for a secure data aggregation protocol. We argue that the secure routing role would be rendered useless if the data aggregation scheme built on it is not secure. Conversely, the secure data aggregation protocol needs a secure underlying routing protocol as its foundation in order to be effectively optimal. As an attempt for the solution, we devise an energy-aware protocol based on LEACH and ESPDA that combines secure routing protocol and secure data aggregation protocol. We then evaluate its security effectiveness and its energy-efficiency aspects, knowing that there are always trade-off between both.

7.
Sensors (Basel) ; 14(8): 14786-805, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-25123464

RESUMEN

Internet of Things is a ubiquitous concept where physical objects are connected over the internet and are provided with unique identifiers to enable their self-identification to other devices and the ability to continuously generate data and transmit it over a network. Hence, the security of the network, data and sensor devices is a paramount concern in the IoT network as it grows very fast in terms of exchanged data and interconnected sensor nodes. This paper analyses the authentication and access control method using in the Internet of Things presented by Jing et al. (Authentication and Access Control in the Internet of Things. In Proceedings of the 2012 32nd International Conference on Distributed Computing Systems Workshops, Macau, China, 18-21 June 2012, pp. 588-592). According to our analysis, Jing et al.'s protocol is costly in the message exchange and the security assessment is not strong enough for such a protocol. Therefore, we propose improvements to the protocol to fill the discovered weakness gaps. The protocol enhancements facilitate many services to the users such as user anonymity, mutual authentication, and secure session key establishment. Finally, the performance and security analysis show that the improved protocol possesses many advantages against popular attacks, and achieves better efficiency at low communication cost.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Seguridad Computacional/instrumentación , Internet/instrumentación , Tecnología Inalámbrica/instrumentación , Algoritmos , Comunicación , Humanos
8.
ScientificWorldJournal ; 2014: 983901, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25165754

RESUMEN

There are many malware applications in Smartphone. Smartphone's users may become unaware if their data has been recorded and stolen by intruders via malware. Smartphone--whether for business or personal use--may not be protected from malwares. Thus, monitoring, detecting, tracking, and notification (MDTN) have become the main purpose of the writing of this paper. MDTN is meant to enable Smartphone to prevent and reduce the number of cybercrimes. The methods are shown to be effective in protecting Smartphone and isolating malware and sending warning in the form of notification to the user about the danger in progress. In particular, (a) MDTN process is possible and will be enabled for Smartphone environment. (b) The methods are shown to be an advanced security for private sensitive data of the Smartphone user.


Asunto(s)
Teléfono Celular/instrumentación , Teléfono Celular/normas , Seguridad Computacional/tendencias , Aplicaciones Móviles/tendencias
9.
Sensors (Basel) ; 14(2): 2732-55, 2014 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-24521942

RESUMEN

Robust security is highly coveted in real wireless sensor network (WSN) applications since wireless sensors' sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring). The proposed framework offers: (i) key initialization; (ii) secure network (cluster) formation (i.e., mutual authentication and dynamic key establishment); (iii) key revocation; and (iv) new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications.

10.
NMR Biomed ; 26(12): 1751-61, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24000143

RESUMEN

Single-slab three-dimensional (3D) turbo spin-echo (TSE) imaging combined with inversion recovery (IR), which employs short, spatially non-selective refocusing pulses and signal prescription based variable refocusing flip angles (VFA) to increase imaging efficiency, was recently introduced to produce fluid-attenuated brain images for lesion detection. Despite the advantages, the imaging efficiency in this approach still remains limited because a substantially long time of inversion is needed to selectively suppress the signal intensity of cerebrospinal fluid (CSF) while fully recovering that of brain tissues. The purpose of this work is to develop a novel, rapid hybrid encoding method for highly efficient whole-brain fluid-attenuated imaging. In each time of repetition, volumetric data are continuously encoded using the hybrid modular acquisition in a sequential fashion even during IR signal transition, wherein reversed fast imaging with steady-state free precession (PSIF) is employed to encode intermediate-to-high spatial frequency signals prior to CSF nulling, while VFA-TSE is used to collect low-to-intermediate spatial frequency signals afterwards. Gradient-induced spin de-phasing between a pair of neighboring radio-frequency (RF) pulses in both PSIF and TSE modules is kept identical to avoid the occurrence of multiple echoes in a single acquisition window. Additionally, a two-step, alternate RF phase-cycling scheme is employed in the low spatial frequency region to eliminate free induction decay induced edge artifacts. Numerical simulations of the Bloch equations were performed to evaluate signal evolution of brain tissues along the echo train while optimizing imaging parameters. In vivo studies demonstrate that the proposed technique produces high-resolution isotropic fluid-attenuated whole-brain images in a clinically acceptable imaging time with substantially high signal-to-noise ratio for white matter while retaining lesion conspicuity.


Asunto(s)
Encéfalo/metabolismo , Líquido Cefalorraquídeo/metabolismo , Imagenología Tridimensional , Simulación por Computador , Humanos , Persona de Mediana Edad , Procesamiento de Señales Asistido por Computador , Relación Señal-Ruido
11.
J Adv Prosthodont ; 4(3): 146-52, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22977722

RESUMEN

PURPOSE: The cortical bone thickness on the anterior region is important for achieving implant stability. The purpose of this study was to examine the thickness of the cortical and cancellous bones on the anterior region of the maxilla and mandible. MATERIALS AND METHODS: Twenty-five cadaver heads were used (16 male and 9 female; mean death age, 56.7 years). After the long axis of alveolar process was set up, it was measured in 5 levels starting from 2 mm below the cementoenamel junction (L1) at intervals of 3 mm. All data was analysed statistically by one-way ANOVA at the .05 significance level. RESULTS: The cortical bone thickness according to measurement levels in both the labial and lingual sides increased from L1 to L5, and the lingual side below L3 was significantly thicker than the labial side on the maxilla and mandible. In particular, the labial cortical bone thickness in the maxilla was the thinnest compared to the other regions. The cancellous bone thickness according to measurement levels increased from L1 to L5 on the maxilla, and on the mandible it was the thinnest at the middle level of the root. CONCLUSION: For implant placement on the anterior region, a careful evaluation and full knowledge on the thickness of the cortical and cancellous bone are necessary, therefore, these results may provide an anatomic guideline to clinicians.

12.
Sensors (Basel) ; 12(2): 1625-47, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22438729

RESUMEN

A wireless medical sensor network (WMSN) can sense humans' physiological signs without sacrificing patient comfort and transmit patient vital signs to health professionals' hand-held devices. The patient physiological data are highly sensitive and WMSNs are extremely vulnerable to many attacks. Therefore, it must be ensured that patients' medical signs are not exposed to unauthorized users. Consequently, strong user authentication is the main concern for the success and large scale deployment of WMSNs. In this regard, this paper presents an efficient, strong authentication protocol, named E-SAP, for healthcare application using WMSNs. The proposed E-SAP includes: (1) a two-factor (i.e., password and smartcard) professional authentication; (2) mutual authentication between the professional and the medical sensor; (3) symmetric encryption/decryption for providing message confidentiality; (4) establishment of a secure session key at the end of authentication; and (5) professionals can change their password. Further, the proposed protocol requires three message exchanges between the professional, medical sensor node and gateway node, and achieves efficiency (i.e., low computation and communication cost). Through the formal analysis, security analysis and performance analysis, we demonstrate that E-SAP is more secure against many practical attacks, and allows a tradeoff between the security and the performance cost for healthcare application using WMSNs.


Asunto(s)
Algoritmos , Redes de Comunicación de Computadores/instrumentación , Monitoreo Ambulatorio/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Telemedicina/instrumentación , Telemetría/instrumentación , Transductores , Seguridad Computacional , Confidencialidad , Diseño de Equipo , Análisis de Falla de Equipo
13.
Sensors (Basel) ; 12(1): 55-91, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22368458

RESUMEN

Healthcare applications are considered as promising fields for wireless sensor networks, where patients can be monitored using wireless medical sensor networks (WMSNs). Current WMSN healthcare research trends focus on patient reliable communication, patient mobility, and energy-efficient routing, as a few examples. However, deploying new technologies in healthcare applications without considering security makes patient privacy vulnerable. Moreover, the physiological data of an individual are highly sensitive. Therefore, security is a paramount requirement of healthcare applications, especially in the case of patient privacy, if the patient has an embarrassing disease. This paper discusses the security and privacy issues in healthcare application using WMSNs. We highlight some popular healthcare projects using wireless medical sensor networks, and discuss their security. Our aim is to instigate discussion on these critical issues since the success of healthcare application depends directly on patient security and privacy, for ethic as well as legal reasons. In addition, we discuss the issues with existing security mechanisms, and sketch out the important security requirements for such applications. In addition, the paper reviews existing schemes that have been recently proposed to provide security solutions in wireless healthcare scenarios. Finally, the paper ends up with a summary of open security research issues that need to be explored for future healthcare applications using WMSNs.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Seguridad Computacional , Recolección de Datos , Atención a la Salud/métodos , Electrónica Médica/instrumentación , Tecnología Inalámbrica/instrumentación , Redes de Comunicación de Computadores/legislación & jurisprudencia , Seguridad Computacional/legislación & jurisprudencia , Atención a la Salud/legislación & jurisprudencia , Electrónica Médica/legislación & jurisprudencia , Tecnología Inalámbrica/legislación & jurisprudencia
14.
Sensors (Basel) ; 11(5): 5020-46, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22163888

RESUMEN

In recent years, wireless sensor networks (WSNs) have been considered as a potential solution for real-time monitoring applications and these WSNs have potential practical impact on next generation technology too. However, WSNs could become a threat if suitable security is not considered before the deployment and if there are any loopholes in their security, which might open the door for an attacker and hence, endanger the application. User authentication is one of the most important security services to protect WSN data access from unauthorized users; it should provide both mutual authentication and session key establishment services. This paper proposes a robust user authentication framework for wireless sensor networks, based on a two-factor (password and smart card) concept. This scheme facilitates many services to the users such as user anonymity, mutual authentication, secure session key establishment and it allows users to choose/update their password regularly, whenever needed. Furthermore, we have provided the formal verification using Rubin logic and compare RUASN with many existing schemes. As a result, we found that the proposed scheme possesses many advantages against popular attacks, and achieves better efficiency at low computation cost.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Seguridad Computacional/instrumentación , Tecnología Inalámbrica/instrumentación
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