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Blockchain has been adopted to address significant challenges, such as trust in diverse domains, including voting, logistics and finance. However, transaction malleability has been identified as a threat for blockchain, which can potentially lead to an inconsistent state that can result in further attacks such as double-spending. In this context, this paper is focused on investigating the feasibility of transaction malleability within a typical blockchain application aiming to identify scenarios that may lead to a successful transaction malleability attack. Our objective in doing so is to highlight conditions which cause such attack to facilitate the development of protection mechanisms for them. Specifically, this paper presents a successful simulation of transaction malleability attack within the context of blockchain-based electronic voting. The evaluation has identified the impact of parameters, such as network delay and block generation rate in achieving a successful transaction malleability attack, which highlights future directions of research.

The inception of quantum key distribution (QKD) empowered the communication networks with unconditional security because of the unique characteristics of quantum mechanics. Since QKD genesis, various protocols have been proposed to augment the feasibility of its real-world implementation and to overcome the inherent vulnerabilities of communication channel. In the past several years' studies emphasize the significance of QKD in the field of secure communication, because it can counter critical attacks quite effectively. In this paper, we present in-depth security analysis of the notable QKD protocols which encompasses from their theoretical assertions to their practical implementation factors and simulation outcomes.

Voting is one of the fundamental pillars of modern democracy. Continuous efforts have been made to strengthen the processes and methods involved to achieve verifiable, transparent voting systems. In recent years, blockchain has been increasingly used to address multi-dimensional challenges across widespread application domains including healthcare, finance and e-voting. However, achieving an efficient solution via use of blockchain requires consideration of a range of factors such as block generation rate, transaction speed, and block size which have a profound role in determining the overall performance of the solution. Current research into this aspect of blockchain is focused on Bitcoin with the objective to achieve comparable performance as of existing online payment systems such as VISA. However, there exists a gap in literature with respect to investigating performance constraints for wider application domains. In this paper, we present our efforts to address this gap by presenting a detailed study into performance and scalability constraints for an e-voting system. Specifically, we conducted rigorous experimentation with permissioned and permissionless blockchain settings across different scenarios with respect to voting population, block size, block generation rate and transaction speed. The experiments highlighted interesting observations with respect to the impact of these parameters on the overall efficiency and scalability of the e-voting model including trade-offs between different parameters as well as security and performance.\ud present our efforts to address this gap by presenting a detailed study into performance and scalability constraints for an e-voting system. Specifically, we conducted rigorous experimentation with permissioned and permissionless blockchain settings across different scenarios with respect to voting population, block size, block generation rate and transaction speed. The experiments highlighted interesting observations with respect to the impact of these parameters on the overall efficiency and scalability of the e-voting model including trade-offs between different parameters as well as security and performance.

Tunnel Boring Machines (TBMs) are large multi-million pound machines used to excavate underground tunnels. In order to make best use of the high-speed performance of a TBM and guarantee the safety of excavation, it is important to know the local geology, structures and ground properties ahead of the TBM cutter head, especially in complex geological conditions (e.g. karst caves). By working with experienced geophysical experts, tunnelling engineers/consultants and TBM manufacturers, we propose a novel web-based visualisation platform to help TBM operators efficiently manage, process and visualise the TBM parameters, the geology map created by geo-experts based on boreholes, and especially the imaging data captured by an on-board ground imaging system for “seeing through” the ground beyond the excavation surface. Informative visualisation interfaces were designed to facilitate interpretation of the imaging data and adding annotation by users; algorithms were developed for automatic detection of features and probable events by fusion of radar and seismic imaging data; and a back-end database was designed to store all such relevant information for supporting more advanced interpretation in the future. The web-based architecture not only allows the visualisation platform to be directly linked to on-board sensors (e.g. ground penetrating radars, seismic sensors), but also allows users away from the job site to access the captured data using a standard web browser, enabling a collaborative interpretation process. The data processing, management and visualisation platform presented in this paper is flexible with respect to different imaging sensors and modalities, so it is highly adaptable for any other ground imaging systems for tunnel geology inspection, underground utility surveys, etc.

Quantum key distribution (QKD) is one of the exciting applications of quantum mechanics. It allows the sharing of secret keys between two communicating parties with unconditional security. A variety of QKD protocols have been proposed since the inception of the BB84 protocol. Among different implementation techniques of QKD protocols, there is a category which exploits higher dimensions qubit states to encode classical bits. In this paper, we focus on such a QKD protocol called KXB10, which uses three bases with higher dimensions. Analysis of the generalized dimension quantum states is performed by evaluating it based on the index transmission error rate ITER. We find that there is a direct relationship between qubit dimensions and ITER for the KXB10 protocol.

Quantum key distribution (QKD) is a proven secured way to transmit shared secret keys using quantum particles. Any adversarial attempt to intercept and eavesdrop secret key results in generating errors alerting the legitimate users. Since QKD is constrained by quantum mechanics principles, the practical transmission of the key at a greater distance is an issue. In this paper, we discover and analyze the key factors associated with transmission media, hardware components and protocol implementation of the QKD system that causes hindrance in distance range. Practical implementation of BB84 and KMB09 protocols is discussed to determine the achievable distance given current technology. We find that by using ultra low loss fiber, short-pulse laser and superconducting nanowire single photon detector the maximum achievable distance for both of the quantum protocols is 250[Formula: see text]km.

A n efficient in vitro propagation protocol for Artemi sia amygdalina D . d eveloped here resulted in the induction of s ignificantly more number of shoo ts (36 shoots per nodal explant ) on a medium containing 10 µM benzyl amino purine (BAP) and 10 µM α - naphthaleneacetic acid (NAA) than any other treatment. Growth of the regenerated shoots in phytohormone free MS medium resulted in a significant increase in biomass, shoot height and shoot multiplication. The regenerated shoots also formed roots when transferred onto full strength and half strength MS (Murashige and Skoog) medium . Healthy in vitro raised plantlets were acclimatized and maintained in standard greenhouse conditions for further growth. T his study provides a basis for germplasm conservatio n and further investigation of this rare, medicinally important plant species.

There are a number of different strategies to measure the phase shift between two pathways of light more efficiently than suggested by the standard quantum limit. One way is to use highly entangled photons. Another way is to expose photons to a non-linear or interacting Hamiltonian. This paper emphasises that the conditional dynamics of open quantum systems provides an interesting additional tool for quantum-enhanced metrology. As a concrete example, we review a recent scheme which exploits the conditional dynamics of a laser-driven optical cavity with spontaneous photon emission inside a quantum feedback loop. Deducing information from second-order photon correlation measurements requires neither optical non-linearities nor entangled photons and should therefore be of immediate practical interest., Comment: 6 pages, 3 figures, IEEE conference proceedings

Android has become a major player in smartphone software arena, thanks to the massively positive reception of Google Play by the developers and users alike. In general, Android applications follow a set of permissions, which are used for access control. However, through the privilege-escalation vulnerability, a malicious application can escalate itself and access an un-permitted resource. Consequently, serious security and safety exploits such as privacy violation, reverse-shell access to the device, and drive-by downloads may occur. We propose a flexible and efficient defense mechanism against such exploits. Our solution — SAndroid, is an extensible and a lightweight application. It provides enhanced safety and security against privilege escalation attacks through rapid detection. SAndroid is based on active monitoring and detection of malicious applications through tracking of system logs and malicious process signatures. The assurance of safety provided by SAndroid is confirmed through design, testing, and verification. SAndroid follows modular approach permitting high flexibility and efficiency. Through real experiments, we confirmed that SAndroid is an efficient and low cost solution having negligible false-positives. This paper describes the architecture and design of the SAndroid framework and provides details of our experiments.

BackgroundIn Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression.Methods and findingsLay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3%) started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000) at the hospital and 763 (prevalence 131/100,000) at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2-3 weeks (RR 0.66 95%CI [0.49-0.90]) and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03-1.18]). Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63-0.92]) and more likely to have +1 smear grade (RR 1.24 95%CI [1.02-1.51]).ConclusionsTuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such as chest x-ray and Xpert MTB/RIF may improve results.

To determine the seropositivity of Immunoglobulin-G and Immunoglobulin-M to hepatitis E virus in male blood donors in Makkah, Saudi Arabia.The study was carried out from March to August 2009, in which 900 blood samples were collected from 4 different hospital blood banks in Makkah City: AL-Noor Hospital, Central Blood Bank, Maternity and Children Hospital, and Herra Hospital. All the samples were tested for Immunoglobulin-G and Immunoglobulin-M antibodies specific to hepatitis E virus using the enzyme-linked immunosorbent assay test.Hepatitis E virus-specific Immunoglobulin-G antibodies were detected in 168/900 (18.7%), and IgM in 39/900 (4.3%) samples. Prevalence of the former was found to be higher in non-Saudi donors. In addition, its prevalence increased with age. Moreover, its prevalence was found to be higher in uneducated donors and in donors who drank well-water.Exposure to hepatitis E virus among blood donors in Makkah City was high in comparison to the neighbouring areas in the region. Further studies are warranted to determine the true seroprevalence of the virus in the society at large.

OBJECTIVES: Children with various single ventricle anomalies are at risk of developing systemic ventricular outflow tract obstruction (SVOTO) following volume unloading with cavopulmonary connection (CPC). We aim to evaluate the value of Damus–Kaye–Stansel (DKS) anastomosis at the time of CPC in eliminating late SVOTO risk. METHODS: Retrospective review of single ventricle patients who underwent DKS concurrent with CPC between 1997 and 2012 was performed. Clinical, echocardiographic and angiographic outcomes were analysed. RESULTS: Thirty-six children with single ventricle underwent DKS at the time of Glenn bidirectional CPC (n= 29) or Fontan total CPC (n= 7). The underlying anatomy was double inlet left ventricle (n= 18), double outlet right ventricle (n= 8), unbalanced atrioventricular septal defect (n= 4) and other (n= 6). Prior palliation included pulmonary artery band (n= 35), coarctation/arch repair (n= 11) and atrial septectomy (n= 8). Median age at the time of DKS was 8.9 months (range 3.6 months–9.1 years) and the median weight was 6.7 kg (range 5–27 kg). At the time of DKS, 17 patients (47%) had no SVOT gradient and 19 (53%) had SVOT gradient (mean 23.4 ± 18.7 mmHg). Overall survival was 89 and 83% at 1 month and 5 years, respectively. None of the deaths were related to SVOTO or DKS complications. When present, SVOT gradient decreased from 23.4 ± 18.7 mmHg preoperatively to 0 after DKS (P< 0.001). At the last follow-up, none of the patients developed any SVOT gradient; 78% of them had zero or trivial aortic/neoaortic valve regurgitation while 22% had mild regurgitation. None of the patients had evidence of compression of the left pulmonary artery or bronchus. Eighty-one percent of patients have reached or are suitable candidates awaiting final palliative surgery. CONCLUSIONS: DKS can be safely performed in conjunction with CPC without added mortality risk. It is very effective in mitigating SVOTO risk, with sustainable good semilunar valves function. Our data support an aggressive approach to performing DKS concurrent with CPC in children with single ventricle pathologies at risk of developing SVOTO.

Quantum key distribution (QKD) has been developed within the last decade that is provably secure against arbitrary computing power, and even against quantum computer attacks. Now there is a strong need of research to exploit this technology in the existing communication networks. In this paper we have presented various experimental results pertaining to QKD like Raw key rate and Quantum bit error rate (QBER). We found these results over 25 km single mode optical fiber. The experimental setup implemented the enhanced version of BB84 QKD protocol. Based upon the results obtained, we have presented a network design which can be implemented for the realization of large scale QKD networks. Furthermore, several new ideas are presented and discussed to integrate the QKD technique in the classical communication networks., This paper has been submitted to the 2006 International Symposium on Collaborative Technologies and Systems (CTS 2006)May 14-17, 2006, Las Vegas, Nevada, USA

Quantum Key Distribution (QKD) is used in Quantum Cryptographic Systems to exchange secret key between parties who need to communicate secretly. Such a key can be used with a symmetric encryption schemes to establish a secure communication. Until recently, QKD is possible using optical fiber over few tens of kilometers but not more due to single photons getting absorbed by the fiber. There are no commercial wireless quantum crypto products yet, but QKD will soon be used in wireless medium from satellite to the earth so we could get 10,000 miles. But wireless medium brings its own problems. The energy transmitted via a wireless link spreads out, leading to higher and varying transmission losses, ambient daylight, or even light from the moon at night couple into the receiver, leading to a higher error rate. Interference from other photon sources air with clouds, dust and unsettled conditions creates intervention. In this paper, different techniques for communication in Quantum Cryptography using wireless networking infrastructure are discussed.

A 39-year-old male reported fevers, weight loss, watery loose stools, and decreased visual acuity in his right eye over the prior five years. He was pancytopenic, had an elevated American council on exercise level, total bilirubin, and alkaline phosphatase. Computed tomography revealed massive hepatosplenomegaly and emphysematous lung changes. Liver biopsy showed non caseating granulomas. The patient was diagnosed with extrapulmonary sarcoidosis and was treated with prednisone. The patient symptomatically improved but 5 mo later presented with abdominal pain caused by perforation of the cecum. He underwent a cecectomy and pathology revealed pneumatosis cystoides intestinalis. This represents the first reported association between pneumatosis cystoides intestinalis and sarcoidosis. The etiology of pneumatosis cystoides intestinalis in this case was likely multifactorial and involved both effects of the corticosteroids as well as the advanced nature of the gastrointestinal sarcoidosis. Furthermore this case has the unique features of emphysematous lung changes and pancytopenia which are uncommon with sarcoidosis.

In the original BB84 protocol by Bennett and Brassard, an eavesdropper is detected because his attempts to intercept information result in a quantum bit error rate (QBER) of at least 25%. Here we design an alternative quantum key distribution protocol, where Alice and Bob use two mutually unbiased bases with one of them encoding a "0" and the other one encoding a "1." The security of the scheme is due to a minimum index transmission error rate (ITER) introduced by an eavesdropper which increases significantly for higher-dimensional photon states. This allows for more noise in the transmission line, thereby increasing the possible distance between Alice and Bob without the need for intermediate nodes., 17 pages, 3 figures, 4 tables, discussion of QBER added

The proliferation of sensor devices has introduced\ud exciting possibilities such as the Internet of Things (IoT). Machine to Machine (M2M) communication underpins efficient interactions within such infrastructures. The resource constraints and ad-hoc nature of these networks have significant implications for security in general and with respect to intrusion detection in particular. Consequently, contemporary solutions mandating a stable infrastructure are inadequate to fulfill these defining\ud characteristics of M2M networks. In this paper, we present COLIDE (COLlaborative Intrusion Detection Engine) a novel framework for effective intrusion detection in the M2M networks without incurring high energy and communication cost on the participating host and edge nodes. The framework is envisioned to address challenges such as flexibility, resource constraints, and the collaborative nature of the M2M networks. The paper\ud presents a detailed system description along with its formal and empirical evaluation using Contiki OS. Our evaluation for different communication scenarios demonstrates that the proposed approach has limited overhead in terms of energy utilization and memory consumption.