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Passwords are the first line of defence against preventing unauthorised access to systems and potential leakage of sensitive data. However, the traditional reliance on username and password combinations is not enough protection and has prompted the implementation of technologies such as two-factor authentication (2FA). While 2FA enhances security by adding a layer of verification, these techniques are not impervious to threats. Even with the implementation of 2FA, the relentless efforts of cybercriminals present formidable obstacles in securing digital spaces. The objective of this work is to implement blockchain technology as a form of 2FA. The findings of this work suggest that blockchain-based 2FA methods could strengthen digital security compared to conventional 2FA methods.

Introduction Drug‐eluting stent (DES) use in symptomatic intracranial atherosclerosis disease (ICAD) has been described in the literature using different guiding and distal access catheters. We describe a case of deployment of a Xience Skypoint everolimus‐eluting stent (EES) (Abbott Vascular, Abbott Park, Illinois) into a symptomatic stenosed left M1 segment using Armadillo catheter (Q'Apel, Fremont, CA) with a successful result. Methods Case report and review of literature Results 67‐year‐old woman with type II diabetes mellitus, hypertension, hyperlipidemia, and recent admission for transient ischemic attack (resolving right hemiparesis and mild dysnomia in the setting of severe left M1 segment stenosis with discharge on Aspirin, Clopidogrel and Atorvastatin), presented with recurrence of symptoms, and MRI brain showing left basal ganglia acute infarction. No tPA was given low NIHSS and resolution of symptoms. Patient’s aphasia and hemiparesis worsened with segmental hypoperfusion which resolved by maintaining high blood pressures with norepinephrine drip. Decision was made to deploy a drug eluting stent into the stenosed M1 segment. Through femoral access, a 7F long destination sheath was inserted to the left common carotid origin. A 7F Armadillo catheter was then inserted into the left internal carotid artery (ICA) terminus. ASAHI Prowater coronary guidewire was inserted over which Xience Skypoint EES deployment was attempted but was unsuccessful given difficulty traversing the ICA ophthalmic segment. Ultimately, Armadillo catheter was advanced over a Phenom catheter (Medtronic) with good access into the distal M1 segment. The Phenom intermediate catheter was then removed, and the 2.25 mm x 12 mm stent was introduced through the Prowater guidewire into the segment and inflated to a pressure of 8 atm, with restoration of blood flow. Postoperatively, SBP was lowered to prevent reperfusion injury. Patient’s exam stabilized with mild dysnomia and right hemiparesis without any elevated blood pressure requirements. At 5‐months follow‐up, patient’s exam was non‐focal with NIHSS 0 and repeat DSA showed no evidence of stent occlusion and patent M1 segment. Conclusion Xience Skypoint EES can be successful in treating symptomatic MCA stenosis refractory to maximal medical therapy with good long term results.

Introduction Zoom reperfusion system (Imperative Care, CA) has proven to be promising for use in mechanical thrombectomies in adults but has not been described in pediatrics to our knowledge. We present two cases of a 14‐year‐old boy with acute right middle cerebral artery (MCA) syndrome and a 10‐year‐old boy with acute left MCA syndrome who underwent mechanical thrombectomy using Zoom Reperfusion System safely with TICI 2B and 3 recanalization respectively. Methods Case report and review of literature Results Case 1: 14‐year‐old previously healthy boy presented to our facility for acute right MCA syndrome secondary to right supraclinoid internal carotid artery (ICA) occlusion. After receiving alteplase, patient was taken for mechanical thrombectomy. After femoral access was obtained, an 8‐French sheath was introduced into the right femoral artery through which a Zoom 88 catheter and 5‐French BERN catheter (Terumo) were coaxially advanced over a Terumo Glidewire into the right common carotid artery. Under roadmap guidance, the Zoom 88 catheter was parked at the lacerum ICA segment with BERN catheter and Glidewire then removed. Angiogram demonstrated complete occlusion of the ICA just past the origin of the ophthalmic artery. Via Zoom 88 catheter, a Zoom 71 catheter was then navigated to the face of clot over a velocity microcatheter (Penumbra) and synchro 2 wire system (Stryker) which was then removed. The vacuum manifold was then attached to Zoom 71 catheter and allowed to engage with the clot for 3 minutes prior to withdrawal into the Zoom 88 catheter. TICI 2B recanalization was achieved with sub‐occlusive thrombus within the proximal M1 segment. Retrieval of the sub‐occlusive thrombus in the M1 segment was performed with TREVO stentriever (Stryker). Procedure was complicated by vasospasm in the A1 and M2 segments which resolved with milrinone and verapamil infused through the Zoom 88 catheter. Case 2: 10‐year‐old with left hypoplastic heart syndrome presented to our facility for acute left MCA syndrome due to left ICA terminus occlusion. Mechanical thrombectomy was performed after receiving alteplase. Femoral artery access was obtained with a 8‐French sheath, through which Zoom 88 catheter and 5‐French select catheter (Penumbra) were advanced over Terumo Glidewire into the left common carotid artery. Under roadmap guidance, the Zoom 88 catheter was parked at the ophthalmic segment of ICA with select catheter and Glidewire then removed. Angiogram demonstrated complete occlusion at the ICA terminus. Zoom 71 catheter was introduced through Zoom 88 catheter and navigated to the face of clot at the ICA terminus over velocity microcatheter (Penumbra) and synchro wire system (Stryker) which was then removed. Zoom 71 was then attached to a vacuum manifold to engage with the clot for 90 seconds. TICI 2A recanalization after first pass was achieved with flow restoration in anterior cerebral artery but none in the MCA.TICI 3 recanalization was achieved after second pass. Conclusion The use of Zoom reperfusion system potentially proves to be safe for use in the pediatric age group with good recanalization results and no intraoperative or postoperative complications.

In this paper, we have addressed the problem of data and location privacy in smart devices over vehicular cloud computing (VCC). We proposed a framework to identify and register the smart GPS devices over VCC service and allow the users to monitor the smart GPS device in real-time. The proposed framework divides into three parts: First, data anonymization of users' information over VCC, by masking the original data of the user and replaced with fake data. The proposed technique will remove the user identity and other linker to identify the users. Second, proposed a technique using an asymmetric cryptography (RSA) technique, the proposed technique provides location privacy of users trajectories before requesting point of interest (POI) from location-based services (LBS). Third, secure communication between users and the VCC, based on Token-based authentication by authenticating the trusted users while requesting a location from the VCC service. The proposed framework shows the efficiency and reliability of responding to the user trajectories from different sources of GPS devices and data-sets.

Farming is a major sector required for any nation to become self-sustainable. Quality seeds heavily influence the effectiveness of farming. Seeds cultivated by breeders pass through several entities in order to reach farmers. The existing seed supply chain is opaque and intractable, which not only hinders the growth of crops but also makes the life of a farmer miserable. Blockchain has been widely employed to enable fair and secure transactions between farmers and buyers, but concerns related to transparency and traceability in the seed supply chain, counterfeit seeds, middlemen involvement, and inefficient processes in the agricultural ecosystem have not received enough attention. To address these concerns, a blockchain-based solution is proposed that brings breeders, farmers, warehouse owners, transporters, and food corporations to a single platform to enhance transparency, traceability, and trust among trust-less parties. A smart contract updates the status of seeds from a breeder from submitted to approved. Then, a non-fungible token (NFT) corresponding to approved seeds is minted for the breeder, which records the date of cultivation and its owner (breeder). The NFT enables farmers to keep track of seeds right from the date of their cultivation and their owner, which helps them to make better decisions about picking seeds from the correct owner. Farmers directly interact with warehouses to purchase seeds, which removes the need for middlemen and improves the trust among trust-less entities. Furthermore, a tender for the transportation of seeds is auctioned on the basis of the priority location locp, Score, and bid_amount of every transporter, which provides a fair chance to every transporter to restrict the monopoly of a single transporter. The proposed system achieves immutability, decentralization, and efficiency inherently from the blockchain. We implemented the proposed scheme and deployed it on the Ethereum network. Smart contracts deployed over the Ethereum network interact with React-based web pages. The analysis and results of the proposed model indicate that it is viable and secure, as well as superior to the current seed supply chain system.

The understanding and implementation of object detection and classification algorithms help in deploying diverse applications of UAVs. There is a need for a simulated UAV dataset to incorporate a pipeline for various algorithms. To reduce human efforts, multiple simulators have been utilized to mimic the real-time behavior of drones. Our work inspired simulators and can be considered by engineering students to create a dataset in a simulated environment. In this paper, we focused on the study of MATLAB-based Simulink through multiple environment settings. The core objective of the paper is to create a simulated dataset from the utilized quadcopter-based flight control model in MATLAB-based Simulink. In this customized model, few modifications have been made to obtain drone videos to detect object categories such as pedestrians, other drones and obstacles while navigating in a simulated environment. Additionally, these simulated images are annotated for aerial image interpretation with multiple object categories. The dataset is annotated and is freely downloadable from: https://bit.ly/38jlAsh. In this research study, we mainly focus on the process of drone simulation in the MATLAB-based Simulink model. Further, the captured dataset is verified on state-of-the-art object detectors such as YoloV3, TinyYolov3 etc. by evaluating the authenticity of the dataset.

Introduction Dolichoectasia is a term used to describe dilated, elongated and tortuous arteries due to defects within the medial layer of their walls secondary to loss of elasticity. Multiple pathophysiological processes might lead to the development of dolichoectatic vessels, and activation of metalloproteinases and irregular turbulent blood flow seem to cause irreversible disruption of the internal elastic lamina. Consequences often include mass effects and ischemic and hemorrhagic stroke. Blood flow within dolichoectatic arteries is turbulent predisposing to thrombus formation with resultant ischemic strokes. Ideally, with optimal anticoagulation therapy, such strokes can be prevented. However, in rare instances, they can still occur despite anticoagulation, likely due to direct compression of pontine perforators from dolichoectasias or persistent turbulent flow. Methods Case report Results A 66‐year‐old woman with hypertension, diabetes mellitus, atrial fibrillation (taking warfarin at home), and left‐sided trigeminal neuralgia due to compressive left vertebrobasilar dolichoectasia with a focal fusiform aneurysm, presented with transient dysarthria and lightheadedness lasting for less than an hour. MRI brain did not show any acute pathology. CTA head showed worsening left vertebrobasilar dolichoectasia with transitional fusiform aneurysm (24 mm in diameter) with mass effect on the anterior part of the pons and lower midbrain. Next day, the patient developed dysarthria and right‐sided weakness, and a repeat MRI brain showed a left acute paramedian pontine infarct. Warfarin was discontinued, and the patient was started on a heparin drip and later transitioned to Apixaban. Eventually, a diagnostic cerebral angiogram and surpass stent placement within the aneurysm were attempted which went uneventful and the flow through the aneurysm regularized. The patient was eventually discharged home on Apixaban and Prasugrel with interval follow‐up. Conclusions Compression of perforating vessels supplying brainstem structures, branching off the pathologic vertebrobasilar dolichoectasia is a rare etiology of acute pontine ischemic stroke, not with standing the anticoagulation. It warrants immediate neurosurgical intervention to optimize blood flow and prevent a recurrence.

The nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DG) has shown promising pharmacological activities, including inhibition of cancerous cell growth and N-glycosylation. It has been used as a glycolysis inhibitor and as a potential energy restriction mimetic agent, inhibiting pathogen-associated molecular patterns. Radioisotope derivatives of 2-DG have applications as tracers. Recently, 2-DG has been used as an anti-COVID-19 drug to lower the need for supplemental oxygen. In the present review, various pharmaceutical properties of 2-DG are discussed.

The emergence of Industry 5.0 has highlighted the significance of information usage, processing, and data analysis when maintaining physical assets. This has enabled the creation of the Digital Twin (DT). Information about an asset is generated and consumed during its entire life cycle. The main goal of DT is to connect and represent physical assets as close to reality as possible virtually. Unfortunately, the lack of security and trust among DT participants remains a problem as a result of data sharing. This issue cannot be resolved with a central authority when dealing with large organisations. Blockchain technology has been proposed as a solution for DT information sharing and security challenges. This paper proposes a Blockchain-based solution for digital twin using Ethereum blockchain with performance and cost analysis. This solution employs a smart contract for information management and access control for stakeholders of the digital twin, which is secure and tamper-proof. This implementation is based on Ethereum and IPFS. We use IPFS storage servers to store stakeholders’ details and manage information. A real-world use-case of a production line of a smartphone, where a conveyor belt is used to carry different parts, is presented to demonstrate the proposed system. The performance evaluation of our proposed system shows that it is secure and achieves performance improvement when compared with other methods. The comparison of results with state-of-the-art methods showed that the proposed system consumed fewer resources in a transaction cost, with an 8% decrease. The execution cost increased by 10%, but the cost of ether was 93% less than the existing methods.

The amalgamation of heterogeneous generations of mobile cellular networks around the globe has resulted in diverse data speed experiences for end users. At present, there are no defined mechanisms in place for subscribers of a mobile network operator (MNO) to use the services of third-party WiFi providers. MNOs also have no standardized procedures to securely interact with each other, and allow their subscribers to use third-party services on a pay-as-you-go basis. This paper proposes a blockchain-enabled offloading framework that allows a subscriber of a mobile operator to temporarily use another MNO or WiFi provider’s higher-speed network. A smart contract is employed to allow diverse entities, such as MNOs, brokers and WiFi providers, to automatically execute mutual agreements, to enable the utilization of third-party infrastructure in a secure and controlled manner. The proposed framework is tested using Ethereum’s testnet on the Goerli network using Alchemy and Hardhat. The analysis of the results obtained shows that the proposed technique helps mobile operators to offer improved user experience in the form of average speed and latency. The experiments show that the average time taken to deliver a 500 MB file is reduced from 10.23 s to 0.91 s for the global average scenario, from 6.09 s to 0.50 s for 5G, from 13.50 s to 0.50 s for 4G-LTE, from 41.11 s to 0.49 s for 4G, and from 339.11 s to 0.49 s for the 3G scenario. The results also show that, with WiFi offloading, users from all cellular generations can enjoy a similar quality of services, because delivery time ranges from 0.49 s to 0.91 s for offloaded experiments whereas for the non-offloaded scenario it ranges from 6.09 s to 339.11 s.

The utilization of Internet of Things (IoT) devices in various smart city and industrial applications is growing rapidly. Within a trusted authority (TA), such as an industry or smart city, all IoT devices are closely monitored in a controlled infrastructure. However, in cases where an IoT device from one TA needs to communicate with another IoT device from a different TA, the trust establishment between these devices becomes extremely important. Obtaining a digital certificate from a certificate authority for each IoT device can be expensive. To solve this issue, a group authentication framework is proposed that can establish trust between group IoT devices owned by different entities. The Chebyshev polynomial has many important properties, semigroup is one of the most important. These properties make the Chebyshev polynomial a good candidate for the proposed group authentication mechanism. The secure exchange of information between trusted authorities is supported by Blockchain technology. The proposed framework was implemented and tested using Python and deployed on Blockchain using Ethereum’s Goerli’s testnet. The results show that the proposed framework can reasonably use Chebyshev polynomials with degrees up to four digits in length. The values of various parameters related to Blockchain are also discussed to understand the usability of the proposed framework.

Advancement in the Internet of Things (IoT) and cloud computing has escalated the number of connected edge devices in a smart city environment. Having billions more devices has contributed to security concerns, and an attack-proof authentication mechanism is the need of the hour to sustain the IoT environment. Securing all devices could be a huge task and require lots of computational power, and can be a bottleneck for devices with fewer computational resources. To improve the authentication mechanism, many researchers have proposed decentralized applications such as blockchain technology for securing fog and IoT environments. Ethereum is considered a popular blockchain platform and is used by researchers to implement the authentication mechanism due to its programable smart contract. In this research, we proposed a secure authentication mechanism with improved performance. Neo blockchain is a platform that has properties that can provide improved security and faster execution. The research utilizes the intrinsic properties of Neo blockchain to develop a secure authentication mechanism. The proposed authentication mechanism is compared with the existing algorithms and shows that the proposed mechanism is 20 to 90 per cent faster in execution time and has over 30 to 70 per cent decrease in registration and authentication when compared to existing methods.

Abstract A convenient and efficient approach for the synthesis of novel 1,2,3-triazole tethered isoindol-1,3-dione conjugates by a nucleophilic substitution reaction of phthalic anhydride with 1,2,3-triazole containing carbohydrazide is described. The latter were prepared by using click chemistry.

The use of low-cost sensors in IoT over high-cost devices has been considered less expensive. However, these low-cost sensors have their own limitations such as the accuracy, quality, and reliability of the data collected. Fog computing offers solutions to those limitations; nevertheless, owning to its intrinsic distributed architecture, it faces challenges in the form of security of fog devices, secure authentication and privacy. Blockchain technology has been utilised to offer solutions for the authentication and security challenges in fog systems. This paper proposes an authentication system that utilises the characteristics and advantages of blockchain and smart contracts to authenticate users securely. The implemented system uses the email address, username, Ethereum address, password and data from a biometric reader to register and authenticate users. Experiments showed that the proposed method is secure and achieved performance improvement when compared to existing methods. The comparison of results with state-of-the-art showed that the proposed authentication system consumed up to 30% fewer resources in transaction and execution cost; however, there was an increase of up to 30% in miner fees.

A convenient and efficient synthesis of new triazole β-lactam conjugates using click chemistry is described. β-lactam 15 and 16 were prepared using cycloaddition strategy and propargylated at N-1 to afford compounds 17 and 18. Cu-catalyzed click reaction of these β-lactams 17 and 18 with different aryl azides provided 1,2,3-triazole conjugates 6 and 7, respectively. The products were fully characterized spectroscopically and tested against Gram-(+) and Gram-(-) bacteria. Compound 7a and 7c were found to be most active.

Corrosion costs heavily, and its prevention is a multi-billion-dollar industry [...]

Magnesium alloys, given their high strength-to-weight ratio, are very attractive materials for applications such as aerospace and automotive components.[...]

As the field of perovskite emerges, doping presents an optimistic way to upgrade the functionalities of these materials and improve the photoluminescence quantum yield (PLQY). While doping is well‐explored in perovskites, it has received less attention in layered double perovskites (LDPs). Doping with lanthanides is particularly interesting for these wide bandgap materials because of their narrow and intense luminescence spectra. Here, the doping of (PEA)4NaInCl8 LDP (PEA = Phenylethylammonium) with Tb3+ and complex of Tb3+ with hexafluoroacetylacetonate (hfa) is studied, i.e., tetrakis β‐diketonate complex. In both cases, energy transfer from host to dopant leading to photoluminescence (PL) emission due to Tb3+ f‐f transitions is observed. However, in the case of Tb3+ doping, sensitization is not very efficient due to the nonideal alignment of energy levels of the host and resonance acceptor energy levels of Tb3+. Whereas, doping of (PEA)4NaInCl8 with Tb3+ in the form of hfa complex, provides a more ideal energetic environment for the efficient energy transfer from host to Tb3+ in the LDP matrix, resulting in a 20‐fold enhancement in the luminescence efficiency. The doping of Tb3+ and Tb3+ complex in LDP sets the foundation for a new approach for the synthesis of LDPs‐lanthanide host‐guest systems for high PLQY. [ABSTRACT FROM AUTHOR]