ABSTRACT
Wireless sensor networks (WSN) are widely used to provide users with convenient services such as health-care, and smart home. To provide convenient services, sensor nodes in WSN environments collect and send the sensing data to the gateway. However, it can suffer from serious security issues because susceptible messages are exchanged through an insecure channel. Therefore, secure authentication protocols are necessary to prevent security flaws in WSN. In 2020, Moghadam et al. suggested an efficient authentication and key agreement scheme in WSN. Unfortunately, we discover that Moghadam et al.'s scheme cannot prevent insider and session-specific random number leakage attacks. We also prove that Moghadam et al.'s scheme does not ensure perfect forward secrecy. To prevent security vulnerabilities of Moghadam et al.'s scheme, we propose a secure and lightweight mutual authentication protocol for WSNs (WSN-SLAP). WSN-SLAP has the resistance from various security drawbacks, and provides perfect forward secrecy and mutual authentication. We prove the security of WSN-SLAP by using Burrows-Abadi-Needham (BAN) logic, Real-or-Random (ROR) model, and Automated Verification of Internet Security Protocols and Applications (AVISPA) simulation. In addition, we evaluate the performance of WSN-SLAP compared with existing related protocols. We demonstrate that WSN-SLAP is more secure and suitable than previous protocols for WSN environments.
Subject(s)
Computer Security , Confidentiality , Computer Simulation , LogicABSTRACT
BACKGROUND/PURPOSE: Previous studies have suggested that functional dominance in one part of the body can be correlated with functional dominance in another part. Thus, the present research aimed to determine whether brain laterality (handedness, footedness, earedness, and eyedness) was related to mixing ability and chewing side preference. MATERIALS AND METHODS: Fifty-four volunteers who were not undergoing any form of dental treatment took part in this study. Self-defined brain laterality was determined through a questionnaire. The volunteers performed five tasks related to brain laterality, which was identified by the side used to perform three or more of the five tasks. Chewing side preference was determined by observing the main gum location on the occlusal area when volunteers chewed for 30 strokes. Mixing Ability Index (MAI) was measured by analyzing the degree of mixing of two differently colored waxes (height, 3 mm; diameter, 20 mm). Occlusion contact area was measured by taking the maximum intercuspation bite with polysiloxane. RESULTS: Thirty-nine volunteers (72%) showed significant agreement between brain dominance and chewing preference side. The association between brain dominance and MAI was not significant. The occlusal contact area of the dominant side (mean = 48.2 mm2) was significantly wider than that of the nondominant side (25.7 mm2). CONCLUSION: Brain laterality can be explained by the side of functional (preference of the hands, eyes, ears, and feet, and survey) has a positive correlation with chewing preference side. MAI between the brain dominant and nondominant sides was not significant. This shows that mastication efficiency does not differ between dominant and nondominant sides. So, this study suggests that brain dominance is correlated with chewing preference, but it does not affect efficiency of mastication.
ABSTRACT
BACKGROUND: To investigate thickness of the macular ganglion cell complex (mGCC) and circumpapillary retinal nerve fiber layer (cRNFL) in retinal segments without visual field (VF) loss in glaucomatous eyes in which localized VF defects were confined to a single hemifield, using spectral-domain optical coherence tomography (SD-OCT). METHODS: Seventy-one Asian glaucomatous patients and 64 normal subjects underwent mGCC and cRNFL imaging employing RTVue-100 SD-OCT. We compared both thickness parameters in retinal segments without VF defects with those in segments in which such defects were evident, and in matched segments of normal controls. Linear regression analysis was used to investigate the relationship between mGCC and cRNFL thickness parameters of segments with or without VF defects, and glaucoma status based on Humphrey field analyzer (HFA) indices. RESULTS: Mean mGCC thickness in the hemiretinae of glaucomatous eyes without VF defects was 87.2 ± 9.3 µm, significantly lower than in matched control hemiretinae (96.2 ± 5.0 µm; p < 0.001), but significantly higher than in glaucomatous hemiretinae with VF defects (76.4 ± 9.9 µm; p < 0.001). A similar trend was also noted with mean cRNFL thickness. There were significant associations between both thickness parameters in glaucomatous hemiretinae with or without VF loss and degree of VF damage at initial presentation. CONCLUSIONS: Perimetrically normal hemifields of glaucomatous eyes had significantly lower mGCC and cRNFL thicknesses than did the corresponding retinal regions of healthy eyes. SD-OCT may be a useful ancillary diagnostic tool for evaluation of early macular and circumpapillary structural changes in glaucomatous eyes with localized VF defects.
