MOF-BC: A Memory Optimized and Flexible BlockChain for Large Scale Networks

BlockChain (BC) immutability ensures BC resilience against modification or removal of the stored data. In large scale networks like the Internet of Things (IoT), however, this feature significantly increases BC storage size and raises privacy challenges. In this paper, we propose a Memory Optimized and Flexible BC (MOF-BC) that enables the IoT users and service providers to remove or summarize their transactions and age their data and to exercise the "right to be forgotten". To increase privacy, a user may employ multiple keys for different transactions. To allow for the removal of stored transactions, all keys would need to be stored which complicates key management and storage. MOF-BC introduces the notion of a Generator Verifier (GV) which is a signed hash of a Generator Verifier Secret (GVS). The GV changes for each transaction to provide privacy yet is signed by a unique key, thus minimizing the information that needs to be stored. A flexible transaction fee model and a reward mechanism is proposed to incentivize users to participate in optimizing memory consumption. Qualitative security and privacy analysis demonstrates that MOF-BC is resilient against several security attacks. Evaluation results show that MOF-BC decreases BC memory consumption by up to 25\% and the user cost by more than two orders of magnitude compared to conventional BC instantiations

Effect of cardiac rehabilitation on physical and mental health components: A randomized controlled clinical trial

Background and Aim: Cardiovascular disease can affect physical and mental conditions. The purpose of the present study was to investigate the effect of phase 1 and 2 of cardiac rehabilitation on physical and mental health components in the patients with acute coronary syndrome. Materials and methods: This clinical trial study included 50 patients with acute coronary syndrome admitted to the coronary care units of the hospitals of Isfahan University of Medical Sciences between 2013 and 2014. The participants were randomly assigned to control and experimental groups. The experimental group performed cardiac rehabilitation program and the control group received routine care. QOL-sf36 questioner was used before and one month after intervention to assess physical and mental health components. Using SPSS18 software, data were analyzed by T- test. Results: There were no significant differences in the demographic variables and cardiovascular risk factors between the experimental and control groups. The mean scores of physical component and mental component after intervention, were 40.9± 9.9 and 37.7 ±10.4 in the control group and 46.9±8.6 and 45.3±10.6 in the experimental group respectively. The results of T-test showed that the mean scores of physical (p=0.02) and mental (p=0.01) health components in the experimental group were significantly higher than those in the control group. Conclusion: The results of this study showed that cardiac rehabilitation program can improve physical and mental health components in the patients with acute coronary syndrome. © 2016, Kurdistan University of Medical Sciences. All rights reserved

BlockChain: A distributed solution to automotive security and privacy

Interconnected smart vehicles offer a range of sophisticated services that benefit the vehicle owners, transport authorities, car manufacturers and other service providers. This potentially exposes smart vehicles to a range of security and privacy threats such as location tracking or remote hijacking of the vehicle. In this article, we argue that BlockChain (BC), a disruptive technology that has found many applications from cryptocurrencies to smart contracts, is a potential solution to these challenges. We propose a BC-based architecture to protect the privacy of the users and to increase the security of the vehicular ecosystem. Wireless remote software updates and other emerging services such as dynamic vehicle insurance fees, are used to illustrate the efficacy of the proposed security architecture. We also qualitatively argue the resilience of the architecture against common security attacks

Peer-to-Peer EnergyTrade: A Distributed Private Energy Trading Platform

Blockchain is increasingly being used as a distributed, anonymous, trustless framework for energy trading in smart grids. However, most of the existing solutions suffer from reliance on Trusted Third Parties (TTP), lack of privacy, and traffic and processing overheads. In our previous work, we have proposed a Secure Private Blockchain-based framework (SPB) for energy trading to address the aforementioned challenges. In this paper, we present a proof-on-concept implementation of SPB on the Ethereum private network to demonstrates SPB's applicability for energy trading. We benchmark SPB's performance against the relevant state-of-the-art. The implementation results demonstrate that SPB incurs lower overheads and monetary cost for end users to trade energy compared to existing solutions

Imaging resonant dissipation from individual atomic defects in graphene

Conversion of electric current into heat involves microscopic processes that operate on nanometer length-scales and release minute amounts of power. While central to our understanding of the electrical properties of materials, individual mediators of energy dissipation have so far eluded direct observation. Using scanning nano-thermometry with sub-micro K sensitivity we visualize and control phonon emission from individual atomic defects in graphene. The inferred electron-phonon 'cooling power spectrum' exhibits sharp peaks when the Fermi level comes into resonance with electronic quasi-bound states at such defects, a hitherto uncharted process. Rare in the bulk but abundant at graphene's edges, switchable atomic-scale phonon emitters define the dominant dissipation mechanism. Our work offers new insights for addressing key materials challenges in modern electronics and engineering dissipation at the nanoscale

Reduction of the rate of hospitalization in patients with acute coronary syndrome: An action research

Background: Readmission of patients with Acute Coronary Syndrome (ACS) causes many problems for them and their family. This study aimed to improve the quality of care provided to patients with ACS and discover solutions to reduce the rate of readmission among them. Materials and Method: This participatory action research study was done based on Streubert and Carpenter approach. This study included 45 participants (31 patients and 14 stakeholders) and carried out in a hospital affiliated to Isfahan University of Medical Sciences, Iran, from 2013 to 2014. Solutions with high and moderate feasibility, flexibility, and suitability were implemented in each cycle until reaching <15 readmission rate. Data were analyzed using SPSS (V.16) and running descriptive and inferential statistics. Results: In this study, several actions were performed in each cycle such as assigning a free and 24-h telephone line was patients to contact nurses and face-to-face patient's education. Second cycle actions included active participation of all nurses in the education of patients and involvement of families in patient care. By carrying out the first action cycle, the readmission rate reached 35, which was not favorable. By completing the second action cycle, the readmission rate reached 12, which was desirable and significantly lower than the first cycle. Conclusion: Discovering possible solutions with the participation of stakeholders in therapeutic settings that have feasibility, flexibility, and suitability can lead to improved care quality and reduced readmission rate in patients with ACS, especially if the families of the patients also participate in action cycles. © 2021 Wolters Kluwer Medknow Publications. All rights reserved

Dual-gated graphene devices for near-field nano-imaging

Graphene-based heterostructures display a variety of phenomena that are strongly tunable by electrostatic local gates. Monolayer graphene (MLG) exhibits tunable surface plasmon polaritons, as revealed by scanning nano-infrared experiments. In bilayer graphene (BLG), an electronic gap is induced by a perpendicular displacement field. Gapped BLG is predicted to display unusual effects such as plasmon amplification and domain wall plasmons with significantly larger lifetime than MLG. Furthermore, a variety of correlated electronic phases highly sensitive to displacement fields have been observed in twisted graphene structures. However, applying perpendicular displacement fields in nano-infrared experiments has only recently become possible (Ref. 1). In this work, we fully characterize two approaches to realizing nano-optics compatible top-gates: bilayer $\text{MoS}_2$ and MLG. We perform nano-infrared imaging on both types of structures and evaluate their strengths and weaknesses. Our work paves the way for comprehensive near-field experiments of correlated phenomena and plasmonic effects in graphene-based heterostructures