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26 pages, 3504 KB  
Review
The Evolution of Artificial Intelligence in Ocular Toxoplasmosis Detection: A Scoping Review on Diagnostic Models, Data Challenges, and Future Directions
by Dodit Suprianto, Loeki Enggar Fitri, Ovi Sofia, Akhmad Sabarudin, Wayan Firdaus Mahmudy, Muhammad Hatta Prabowo and Werasak Surareungchai
Infect. Dis. Rep. 2025, 17(6), 148; https://doi.org/10.3390/idr17060148 - 8 Dec 2025
Viewed by 728
Abstract
Ocular Toxoplasmosis (OT), a leading cause of infectious posterior uveitis, presents significant diagnostic challenges in atypical cases due to phenotypic overlap with other retinochoroiditides and a reliance on expert interpretation of multimodal imaging. This scoping review systematically maps the burgeoning application of artificial [...] Read more.
Ocular Toxoplasmosis (OT), a leading cause of infectious posterior uveitis, presents significant diagnostic challenges in atypical cases due to phenotypic overlap with other retinochoroiditides and a reliance on expert interpretation of multimodal imaging. This scoping review systematically maps the burgeoning application of artificial intelligence (AI), particularly deep learning, in automating OT diagnosis. We synthesized 22 studies to characterize the current evidence, data landscape, and clinical translation readiness. Findings reveal a field in its nascent yet rapidly accelerating phase, dominated by convolutional neural networks (CNNs) applied to fundus photography for binary classification tasks, often reporting high accuracy (87–99.2%). However, development is critically constrained by small, imbalanced, single-center datasets, a near-universal lack of external validation, and insufficient explainable AI (XAI), creating a significant gap between technical promise and clinical utility. While AI demonstrates strong potential to standardize diagnosis and reduce subjectivity, its path to integration is hampered by over-reliance on internal validation, the “black box” nature of models, and an absence of implementation strategies. Future progress hinges on collaborative multi-center data curation, mandatory external and prospective validation, the integration of XAI for transparency, and a focused shift towards developing AI tools that assist in the complex differential diagnosis of posterior uveitis, ultimately bridging the translational chasm to clinical practice. Full article
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17 pages, 633 KB  
Article
Intra- and Inter-Rater Reliability Analysis of MMSE-K and Tablet PC-Based MMSE-K Kit in Patients with Neurologic Disease
by Seung-Ho Choun, Sang-Woo Lee, Yu-Sun Min, Eunhee Park, Jee-Hyun Kim and Tae-Du Jung
Healthcare 2025, 13(23), 3015; https://doi.org/10.3390/healthcare13233015 - 21 Nov 2025
Viewed by 505
Abstract
Background: The increasing prevalence of dementia and mild cognitive impairment (MCI) underscores the need for reliable and scalable digital cognitive screening tools. Although several studies have validated smartphone- or tablet-based assessments in community-dwelling older adults, few have examined their reliability in clinical [...] Read more.
Background: The increasing prevalence of dementia and mild cognitive impairment (MCI) underscores the need for reliable and scalable digital cognitive screening tools. Although several studies have validated smartphone- or tablet-based assessments in community-dwelling older adults, few have examined their reliability in clinical populations with neurological disorders. This study aimed to evaluate the intra- and inter-rater reliability and agreement between the traditional paper-based Mini-Mental State Examination-Korean version (MMSE-K) and a tablet PC-based MMSE-K kit in patients with neurologic diseases undergoing rehabilitation. Methods: A total of 32 patients with neurological conditions—including stroke-related, encephalitic, and myelopathic disorders—participated in this study. Two occupational therapists (OT-A and OT-B) independently administered both the paper- and tablet-based MMSE-K versions following standardized digital instructions and fixed response rules. The intra- and inter-rater reliabilities of the tablet version were analyzed using intraclass correlation coefficients (ICCs) with a two-week retest interval, while Bland–Altman plots were used to assess agreement between the paper and tablet scores. Results: The tablet-based MMSE-K showed strong agreement with the paper-based version (r = 0.969, 95% CI 0.936–0.985, p = 1.05 × 10−19). Intra- and inter-rater reliabilities were excellent, with ICCs ranging from 0.89 to 0.98 for domain scores and 0.98 for the total score, and the Bland–Altman plots showing acceptable agreement without systematic bias. Minor variability was observed in the Attention/Calculation and Comprehension/Judgment domains. Conclusions: The tablet PC-based MMSE-K kit provides a standardized, examiner-independent, and reliable alternative to the traditional paper version for assessing cognitive function in patients with neurologic diseases. These findings highlight the tool’s potential for clinical deployment in hospital and rehabilitation settings, bridging the gap between traditional paper assessments and automated digital screening. Future multicenter studies with larger, disease-diverse cohorts are warranted to establish normative data and validate its diagnostic precision for broader clinical use. Full article
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33 pages, 3122 KB  
Review
Thermal Side-Channel Threats in Densely Integrated Microarchitectures: A Comprehensive Review for Cyber–Physical System Security
by Amrou Zyad Benelhaouare, Idir Mellal, Michel Saydé, Gabriela Nicolescu and Ahmed Lakhssassi
Micromachines 2025, 16(10), 1152; https://doi.org/10.3390/mi16101152 - 11 Oct 2025
Cited by 1 | Viewed by 4208
Abstract
Densely integrated microarchitectures spanning three-dimensional integrated circuits (3D-ICs), chiplet-based designs, and system-in-package (SiP) assemblies make heat a first-order security concern rather than a mere reliability issue. This review consolidates the landscape of thermal side-channel attacks (TSCAs) on densely integrated microarchitectures: we systematize observation [...] Read more.
Densely integrated microarchitectures spanning three-dimensional integrated circuits (3D-ICs), chiplet-based designs, and system-in-package (SiP) assemblies make heat a first-order security concern rather than a mere reliability issue. This review consolidates the landscape of thermal side-channel attacks (TSCAs) on densely integrated microarchitectures: we systematize observation vectors and threat models, clarify core concepts and assumptions, compare the most credible evidence from the past decade, and distill the main classes of defenses across the hardware–software stack. We also explain why hardening against thermal leakage is integral to cyber–physical system (CPS) security and outline the most promising research directions for the field. The strategic relevance of this agenda is reflected in current policy and funding momentum, including initiatives by the United States Department of Homeland Security and the Cybersecurity and Infrastructure Security Agency (DHS/CISA) on operational technology (OT) security, programs by the National Science Foundation (NSF) on CPS, and Canada’s Regional Artificial Intelligence Initiative and Cyber-Physical Resilience Program (RAII, >CAD 35 million), to bridge advanced microelectronics with next-generation cybersecurity. This survey offers a clear, high-level map of the problem space and a focused baseline for future work. Full article
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32 pages, 530 KB  
Article
Perspectives on the Cybersecurity of the Integrated Navigation System
by Aybars Oruc, Georgios Kavallieratos, Vasileios Gkioulos and Sokratis Katsikas
J. Mar. Sci. Eng. 2025, 13(6), 1087; https://doi.org/10.3390/jmse13061087 - 29 May 2025
Cited by 6 | Viewed by 4971
Abstract
As maritime operations become increasingly reliant on interconnected information technology (IT) and operational technology (OT) systems, ensuring cybersecurity on vessels has become more critical than ever. One of these systems is the Integrated Navigation System (INS), which assists the Officer of Watch (OOW) [...] Read more.
As maritime operations become increasingly reliant on interconnected information technology (IT) and operational technology (OT) systems, ensuring cybersecurity on vessels has become more critical than ever. One of these systems is the Integrated Navigation System (INS), which assists the Officer of Watch (OOW) on the bridge in ensuring safe navigation. The INS comprises several components that may be susceptible to cyber attacks, hence it faces cyber risks that need to be mitigated. Cyber risks are understood differently, depending on perspective. In this paper, we determine the perspective that the research community has of cyber risk, focusing on the INS, and that of professionals representing the maritime industry, and analyze similarities and differences. To this end, we conduct a systematic literature review and interviews with maritime professionals. This study provides useful insights for researchers and professionals seeking to understand the cyber risks of the INS. Full article
(This article belongs to the Section Ocean Engineering)
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42 pages, 4687 KB  
Review
A Review on Blockchain Applications in Operational Technology for Food and Agriculture Critical Infrastructure
by Chengliang Zheng, Xiangzhen Peng, Ziyue Wang, Tianyu Ma, Jiajia Lu, Leiyang Chen, Liang Dong, Long Wang, Xiaohui Cui and Zhidong Shen
Foods 2025, 14(2), 251; https://doi.org/10.3390/foods14020251 - 14 Jan 2025
Cited by 11 | Viewed by 4992
Abstract
The food and agriculture sector is a cornerstone of critical infrastructure (CI), underpinning global food security, public health, and economic stability. However, the increasing digitalization and connectivity of operational technologies (OTs) in this sector expose it to significant cybersecurity risks. Blockchain technology (BT) [...] Read more.
The food and agriculture sector is a cornerstone of critical infrastructure (CI), underpinning global food security, public health, and economic stability. However, the increasing digitalization and connectivity of operational technologies (OTs) in this sector expose it to significant cybersecurity risks. Blockchain technology (BT) has emerged as a transformative solution for addressing these challenges by enhancing network security, traceability, and system resilience. This study presents a comprehensive review of BT applications in OT security for food and agriculture CI, employing bibliometric and content analysis methods. A total of 124 relevant articles were identified from six databases, including the Web of Science Core Collection and MEDLINE®. Bibliometric analysis was conducted across five dimensions: publication year, literature type, journal distribution, country contributions, and keyword trends. The findings are meticulously organized through tables, charts, and graphs. The year 2018 marked a surge in research within this domain, with the IEEE Internet of Things Journal and IEEE ACESS emerging as the most prolific journals, each boasting nine publications. The United States, China, and India are at the forefront in terms of journal citation counts. Our analysis determined that a reference count of 37 serves as an appropriate threshold. Otoum Safa stands out as the author with the highest number of published articles, totaling four. Keywords such as “blockchain”, “internet of things”, “smart contract”, “security”, and “critical infrastructure” appear with significant frequency. The statistics, trends, and insights gleaned from this bibliometric analysis can guide researchers in the OTCI field to forge a coherent and logical research trajectory. Content analysis further identified six key research areas within this domain: identity authentication and data verification, secure access control, attack detection and perception, data security and protection, data backup and recovery, and attack assessment and attribution. Based on these insights, a general framework is proposed to guide future research and practical applications of BT in securing OT within food and agriculture CI. This study systematically analyzes the current research landscape, challenges, and opportunities for BT in securing the OT critical to food and agriculture CI. By bridging the gap between blockchain innovations and the operational needs of the food and agriculture sector, this work contributes to advancing strategic implementation and improving the security of CI systems. Full article
(This article belongs to the Section Food Security and Sustainability)
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24 pages, 1689 KB  
Article
Cyber–Physical Security Assessment for Maritime Vessels: Study on Drillship DP System Using American Petroleum Institute Security Risk Analysis and Bow-Tie Analysis
by Iosif Progoulakis, Ioannis K. Dagkinis, Anastasia Dimakopoulou, Theodoros Lilas, Nikitas Nikitakos and Panagiotis M. Psomas
J. Mar. Sci. Eng. 2024, 12(10), 1757; https://doi.org/10.3390/jmse12101757 - 4 Oct 2024
Cited by 2 | Viewed by 3249
Abstract
The maritime industry’s increasing integration of IT/OT systems into vessel operations has significantly elevated its exposure to cyber–physical threats, making the development of effective cyber risk management strategies a necessity. This paper provides an outlook of the current landscape of cyber security threats [...] Read more.
The maritime industry’s increasing integration of IT/OT systems into vessel operations has significantly elevated its exposure to cyber–physical threats, making the development of effective cyber risk management strategies a necessity. This paper provides an outlook of the current landscape of cyber security threats and vulnerabilities for the maritime sector and vessels. An outline of the relevant governmental and industry directives, standards, and guidelines for cyber security in maritime vessels is given. Considering maritime vessels as critical elements of the maritime critical infrastructure sector, a number of relevant cyber–physical security assessment methods are presented. Bridging cyber–physical security, process safety, and security, API SRA (American Petroleum Institute Security Risk Analysis) and BTA (Bow-Tie Analysis) are presented as the most applicable cyber–physical security assessment methods for complex maritime vessels, such as an offshore oil and gas drillship. The scenario of a cyber-attack on the Dynamic Positioning (DP) system of a drillship is presented with the use of API SRA and BTA. The difficulties in the implementation of NIST CSF v2.0 and IACS UR E26 and UR E27 in the maritime sector are also discussed. The need for intensified research on and the formulation of bespoke cyber security measures to mitigate the evolving cyber threats within the maritime domain is highlighted. The need for the allocation of training and resources for the reinforcement of the capacity of a maritime vessel’s crew in the mitigation of cyber threats and safe maritime operations is emphasized. Full article
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16 pages, 3688 KB  
Article
Aluminium 8-Hydroxyquinolinate N-Oxide as a Precursor to Heterometallic Aluminium–Lanthanide Complexes
by Elisa Gallo, Luca Bellucci, Silvia Carlotto, Gregorio Bottaro, Luca Babetto, Luca Giordano, Fabio Marchetti, Simona Samaritani, Lidia Armelao and Luca Labella
Molecules 2024, 29(2), 451; https://doi.org/10.3390/molecules29020451 - 17 Jan 2024
Cited by 3 | Viewed by 3299
Abstract
A reaction in anhydrous toluene between the formally unsaturated fragment [Ln(hfac)3] (Ln3+ = Eu3+, Gd3+ and Er3+; Hhfac = hexafluoroacetylacetone) and [Al(qNO)3] (HqNO = 8-hydroxyquinoline N-oxide), here prepared for the first time [...] Read more.
A reaction in anhydrous toluene between the formally unsaturated fragment [Ln(hfac)3] (Ln3+ = Eu3+, Gd3+ and Er3+; Hhfac = hexafluoroacetylacetone) and [Al(qNO)3] (HqNO = 8-hydroxyquinoline N-oxide), here prepared for the first time from [Al(OtBu)3] and HqNO, affords the dinuclear heterometallic compounds [Ln(hfac)3Al(qNO)3] (Ln3+ = Eu3+, Gd3+ and Er3+) in high yields. The molecular structures of these new compounds revealed a dinuclear species with three phenolic oxygen atoms bridging the two metal atoms. While the europium and gadolinium complexes show the coordination number (CN) 9 for the lanthanide centre, in the complex featuring the smaller erbium ion, only two oxygens bridge the two metal atoms for a resulting CN of 8. The reaction of [Eu(hfac)3] with [Alq3] (Hq = 8-hydroxyquinoline) in the same conditions yields a heterometallic product of composition [Eu(hfac)3Alq3]. A recrystallization attempt from hot heptane in air produced single crystals of two different morphologies and compositions: [Eu2(hfac)6Al2q4(OH)2] and [Eu2(hfac)6(µ-Hq)2]. The latter compound can be directly prepared from [Eu(hfac)3] and Hq at room temperature. Quantum mechanical calculations confirm (i) the higher stability of [Eu(hfac)3Al(qNO)3] vs. the corresponding [Eu(hfac)3Alq3] and (ii) the preference of the Er complexes for the CN 8, justifying the different behaviour in terms of the Lewis acidity of the metal centre. Full article
(This article belongs to the Special Issue Exclusive Feature Papers in Inorganic Chemistry, 2nd Edition)
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16 pages, 4873 KB  
Article
Reliability-Based Proof Load Factors for Assessment of Bridges
by Christian Overgaard Christensen, Kenneth Dahl Schiøttz Damsgaard, John Dalsgaard Sørensen, Svend Engelund, Per Goltermann and Jacob Wittrup Schmidt
Buildings 2023, 13(4), 1060; https://doi.org/10.3390/buildings13041060 - 18 Apr 2023
Cited by 13 | Viewed by 3892
Abstract
Advanced reliability assessment can be required when evaluating existing bridge structures through proof load testing. The target load of a proof load test typically requires input from resistance models; however, bridges with a low documentation level are often the most relevant for proof [...] Read more.
Advanced reliability assessment can be required when evaluating existing bridge structures through proof load testing. The target load of a proof load test typically requires input from resistance models; however, bridges with a low documentation level are often the most relevant for proof load testing, and resistance models thus involve significant uncertainties. This paper presents a different approach to proof loading and target proof load, in which the resistance model is not included in the determination of this load. Instead, the target proof load is determined based on load models coupled to the desired target failure probability, thus ensuring sufficient safety of the existing bridge. The method is in line with the proposal for a new Eurocode on assessment of existing structures and is deemed to be superior to existing approaches. An essential assumption of the method is that monitoring systems can identify stop criteria before irreversible damage occurs. The approach was applied in a case study, where an OT-slab bridge with a span of 6.5 m was proof-load-tested and reclassified for capacity upgrading of a road stretch in Denmark. Full article
(This article belongs to the Special Issue Experiment and Analysis of Building Structures)
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9 pages, 678 KB  
Article
Evaluation of Load Distribution in a Mandibular Model with Four Implants Depending on the Number of Prosthetic Screws Used for OT-Bridge System: A Finite Element Analysis (FEA)
by Francesco Grande, Mario Cesare Pozzan, Raul Marconato, Francesco Mollica and Santo Catapano
Materials 2022, 15(22), 7963; https://doi.org/10.3390/ma15227963 - 10 Nov 2022
Cited by 14 | Viewed by 2201
Abstract
In full-arch implant rehabilitations, when the anterior screw abutment channel compromises the aesthetic of the patient, the OT-Bridge system used with its Seeger rings may provide the necessary retention of the prosthesis. However, no studies have evaluated the forces generated at the Seeger [...] Read more.
In full-arch implant rehabilitations, when the anterior screw abutment channel compromises the aesthetic of the patient, the OT-Bridge system used with its Seeger rings may provide the necessary retention of the prosthesis. However, no studies have evaluated the forces generated at the Seeger level during loading. This Finite Element Analysis aims to investigate the mechanical behavior of Seeger rings in a mandibular model with four implants and an OT-Bridge system, used without one or two anterior prosthetic screws. A 400 N unilateral load was virtually applied on a 7 mm distal cantilever. Two different variables were considered: the constraint conditions using two or three screws instead of four and the three different framework materials (fiberglass reinforced resin, cobalt-chrome, TiAl6V4). The FEA analysis exhibited tensile and compressive forces on the Seeger closest to the loading point. With the resin framework, a tension force on abutment 3.3 generates a displacement from 5 to 10 times greater than that respectively expressed in metal framework materials. In a full-arch rehabilitation with four implants, the case with three prosthetic screws seems to be a safer and more predictable configuration instead of two. Considering the stress value exhibited and the mechanical properties of the Seeger, the presence of only two prosthetic screws could lead to permanent deformation of the Seeger in the screwless abutment closest to the loading point. Full article
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11 pages, 4001 KB  
Case Report
Full Digital Workflow for Prosthetic Full-Arch Immediate Loading Rehabilitation Using OT-Bridge System: A Case Report
by Marco Piscopo, Francesco Grande and Santo Catapano
Prosthesis 2022, 4(2), 213-223; https://doi.org/10.3390/prosthesis4020021 - 26 Apr 2022
Cited by 5 | Viewed by 6194
Abstract
Nowadays, digital technologies have brought very important advancements in clinical prosthetic dentistry. However, a full digital workflow is still considered to be challenging in the management of full-arch implant cases with immediate prosthetic loading. The aim of this case report is to show [...] Read more.
Nowadays, digital technologies have brought very important advancements in clinical prosthetic dentistry. However, a full digital workflow is still considered to be challenging in the management of full-arch implant cases with immediate prosthetic loading. The aim of this case report is to show a full-digital workflow for the fabrication of an implant-prosthetic fixed provisional prosthesis for immediate loading on seven implants in the upper maxilla. The static guided implant surgery and the OT Bridge prosthetic system were used to rehabilitate the patient. In this way, the combination of a well-known surgical technique with a peculiar prosthetic system that allows for a certain degree of tolerance resulted in it being useful for full-arch immediate loading. Future research and studies are necessary to prove the reliability of this full-digital protocol. Full article
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17 pages, 3188 KB  
Article
Molecular Dynamics Simulation and Cryo-Electron Microscopy Investigation of AOT Surfactant Structure at the Hydrated Mica Surface
by Daniel M. Long, Jeffery A. Greathouse, Guangping Xu and Katherine L. Jungjohann
Minerals 2022, 12(4), 479; https://doi.org/10.3390/min12040479 - 14 Apr 2022
Cited by 8 | Viewed by 4337
Abstract
Structural properties of the anionic surfactant dioctyl sodium sulfosuccinate (AOT or Aerosol-OT) adsorbed on the mica surface were investigated by molecular dynamics simulation, including the effect of surface loading in the presence of monovalent and divalent cations. The simulations confirmed recent neutron reflectivity [...] Read more.
Structural properties of the anionic surfactant dioctyl sodium sulfosuccinate (AOT or Aerosol-OT) adsorbed on the mica surface were investigated by molecular dynamics simulation, including the effect of surface loading in the presence of monovalent and divalent cations. The simulations confirmed recent neutron reflectivity experiments that revealed the binding of anionic surfactant to the negatively charged surface via adsorbed cations. At low loading, cylindrical micelles formed on the surface, with sulfate head groups bound to the surface by water molecules or adsorbed cations. Cation bridging was observed in the presence of weakly hydrating monovalent cations, while sulfate groups interacted with strongly hydrating divalent cations through water bridges. The adsorbed micelle structure was confirmed experimentally with cryogenic electronic microscopy, which revealed micelles approximately 2 nm in diameter at the basal surface. At higher AOT loading, the simulations reveal adsorbed bilayers with similar surface binding mechanisms. Adsorbed micelles were slightly thicker (2.2–3.0 nm) than the corresponding bilayers (2.0–2.4 nm). Upon heating the low loading systems from 300 K to 350 K, the adsorbed micelles transformed to a more planar configuration resembling bilayers. The driving force for this transition is an increase in the number of sulfate head groups interacting directly with adsorbed cations. Full article
(This article belongs to the Special Issue Feature Papers in Clays and Engineered Mineral Materials)
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9 pages, 2642 KB  
Article
Assessment of Preload Loss after Cyclic Loading in the OT Bridge System in an “All-on-Four” Rehabilitation Model in the Absence of One and Two Prosthesis Screws
by Mario Cesare Pozzan, Francesco Grande, Edoardo Mochi Zamperoli, Fabio Tesini, Massimo Carossa and Santo Catapano
Materials 2022, 15(4), 1582; https://doi.org/10.3390/ma15041582 - 20 Feb 2022
Cited by 24 | Viewed by 3137
Abstract
The aim of this study was to evaluate the stability of prosthetic screws after applying cyclic loadings in an “all-on-four” rehabilitation model with the OT Bridge system. The model was tested both with and without anterior screws. Four implant analogues following the “all-on-four” [...] Read more.
The aim of this study was to evaluate the stability of prosthetic screws after applying cyclic loadings in an “all-on-four” rehabilitation model with the OT Bridge system. The model was tested both with and without anterior screws. Four implant analogues following the “all-on-four” concept were inserted in an edentulous mandibular resin model. An OT Bridge system with a Cr–Co prosthetic framework was fabricated. Depending on the presence or absence of one or two anterior screws on the implant analogues, three groups were created, i.e., Gr.1: three tightening screws, Gr.2: two tightening screws, Control Group: four tightening screws. Each single group underwent subsequent 400,000 cyclic loads, simulating approximately a year of chewing by using a dynamometer machine. This cycle was repeated five times for each group, and preload loss values were evaluated on each prosthetic screw after each cycle. All the data obtained were analyzed by one-way ANOVA and Student’s t-test. No statistically significant differences after intragroup analysis were found. A statistically significant difference within the Gr.1 between the screws in positions 33 and 36, equal to 15.2% (p-value = 0.0176), was found. The OT Bridge seems a useful system to maintain the retention of a prosthesis during mechanical stress conditions even in the absence of one screw in an “all-on-four” rehabilitation. This could represent a good solution to solve the esthetic problem of the screw buccal access hole for fixed solutions. Full article
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8 pages, 9075 KB  
Article
Nucleophilic Radiofluorination Using Tri-tert-Butanol Ammonium as a Bifunctional Organocatalyst: Mechanism and Energetics
by Young-Ho Oh, Sandip S. Shinde and Sungyul Lee
Molecules 2022, 27(3), 1044; https://doi.org/10.3390/molecules27031044 - 3 Feb 2022
Cited by 1 | Viewed by 2570
Abstract
We present a quantum chemical analysis of the 18F-fluorination of 1,3-ditosylpropane, promoted by a quaternary ammonium salt (tri-(tert-butanol)-methylammonium iodide (TBMA-I) with moderate to good radiochemical yields (RCYs), experimentally observed by Shinde et al. We obtained the mechanism of the S [...] Read more.
We present a quantum chemical analysis of the 18F-fluorination of 1,3-ditosylpropane, promoted by a quaternary ammonium salt (tri-(tert-butanol)-methylammonium iodide (TBMA-I) with moderate to good radiochemical yields (RCYs), experimentally observed by Shinde et al. We obtained the mechanism of the SN2 process, focusing on the role of the –OH functional groups facilitating the reactions. We found that the counter-cation TBMA+ acts as a bifunctional promoter: the –OH groups function as a bidentate ‘anchor’ bridging the nucleophile [18F]F and the –OTs leaving group or the third –OH. These electrostatic interactions cooperate for the formation of the transition states of a very compact configuration for facile SN2 18F-fluorination. Full article
(This article belongs to the Special Issue Organofluorine Chemistry and Beyond)
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24 pages, 9309 KB  
Article
Digital Image Correlation for Evaluation of Cracks in Reinforced Concrete Bridge Slabs
by Christian Overgaard Christensen, Jacob Wittrup Schmidt, Philip Skov Halding, Medha Kapoor and Per Goltermann
Infrastructures 2021, 6(7), 99; https://doi.org/10.3390/infrastructures6070099 - 7 Jul 2021
Cited by 35 | Viewed by 5919
Abstract
In proof-loading of concrete slab bridges, advanced monitoring methods are required for identification of stop criteria. In this study, Two-Dimensional Digital Image Correlation (2D DIC) is investigated as one of the governing measurement methods for crack detection and evaluation. The investigations are deemed [...] Read more.
In proof-loading of concrete slab bridges, advanced monitoring methods are required for identification of stop criteria. In this study, Two-Dimensional Digital Image Correlation (2D DIC) is investigated as one of the governing measurement methods for crack detection and evaluation. The investigations are deemed to provide valuable information about DIC capabilities under different environmental conditions and to evaluate the capabilities in relation to stop criterion verifications. Three Overturned T-beam (OT) Reinforced Concrete (RC) slabs are used for the assessment. Of these, two are in situ strips (0.55 × 3.6 × 9.0 m) cut from a full-scale OT-slab bridge with a span of 9 m and one is a downscaled slab tested under laboratory conditions (0.37 × 1.7 × 8.4 m). The 2D DIC results includes full-field plots, investigation of the time of crack detection and monitoring of crack widths. Grey-level transformation was used for the in situ tests to ensure sufficient readability and results comparable to the laboratory test. Crack initiation for the laboratory test (with speckle pattern) and in situ tests (plain concrete surface) were detected at intervals of approximately 0.1 mm to 0.3 mm and 0.2 mm to 0.3 mm, respectively. Consequently, the paper evaluates a more qualitative approach to DIC test results, where crack indications and crack detection can be used as a stop criterion. It was furthermore identified that crack initiation was reached at high load levels, implying the importance of a target load. Full article
(This article belongs to the Special Issue Resilient Bridge Infrastructures)
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30 pages, 2521 KB  
Review
Industrial IoT, Cyber Threats, and Standards Landscape: Evaluation and Roadmap
by Lubna Luxmi Dhirani, Eddie Armstrong and Thomas Newe
Sensors 2021, 21(11), 3901; https://doi.org/10.3390/s21113901 - 5 Jun 2021
Cited by 129 | Viewed by 21933
Abstract
Industrial IoT (IIoT) is a novel concept of a fully connected, transparent, automated, and intelligent factory setup improving manufacturing processes and efficiency. To achieve this, existing hierarchical models must transition to a fully connected vertical model. Since IIoT is a novel approach, the [...] Read more.
Industrial IoT (IIoT) is a novel concept of a fully connected, transparent, automated, and intelligent factory setup improving manufacturing processes and efficiency. To achieve this, existing hierarchical models must transition to a fully connected vertical model. Since IIoT is a novel approach, the environment is susceptible to cyber threat vectors, standardization, and interoperability issues, bridging the gaps at the IT/OT ICS (industrial control systems) level. IIoT M2M communication relies on new communication models (5G, TSN ethernet, self-driving networks, etc.) and technologies which require challenging approaches to achieve the desired levels of data security. Currently there are no methods to assess the vulnerabilities/risk impact which may be exploited by malicious actors through system gaps left due to improper implementation of security standards. The authors are currently working on an Industry 4.0 cybersecurity project and the insights provided in this paper are derived from the project. This research enables an understanding of converged/hybrid cybersecurity standards, reviews the best practices, and provides a roadmap for identifying, aligning, mapping, converging, and implementing the right cybersecurity standards and strategies for securing M2M communications in the IIoT. Full article
(This article belongs to the Special Issue State-of-the-Art Sensors Technologies in Ireland 2020)
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