Federated clouds are interconnected cooperative cloud infrastructures offering vast hosting capabilities, smooth workload migration and enhanced reliability. However, recent devastating attacks on ...such clouds have shown that such features come with serious security challenges. The oblivious heterogeneous construction, management, and policies employed in federated clouds open the door for attackers to induce conflicts to facilitate pervasive coordinated attacks. In this paper, we present a novel proactive defense that aims to increase attacker uncertainty and complicate target tracking, a critical step for successful coordinated attacks. The presented systemic approach acts as a VM management platform with an intrinsic multidimensional hierarchical attack representation model (HARM) guiding a dynamic, self and situation-aware VM live-migration for moving-target defense (MtD). The proposed system managed to achieve the proposed goals in a resource-, energy-, and cost-efficient manner.
Resistive switching offers a promising route to universal electronic memory, potentially replacing current technologies that are approaching their fundamental limits. In many cases switching ...originates from the reversible formation and dissolution of nanometre-scale conductive filaments, which constrain the motion of electrons, leading to the quantisation of device conductance into multiples of the fundamental unit of conductance, G0. Such quantum effects appear when the constriction diameter approaches the Fermi wavelength of the electron in the medium - typically several nanometres. Here we find that the conductance of silicon-rich silica (SiOx) resistive switches is quantised in half-integer multiples of G0. In contrast to other resistive switching systems this quantisation is intrinsic to SiOx, and is not due to drift of metallic ions. Half-integer quantisation is explained in terms of the filament structure and formation mechanism, which allows us to distinguish between systems that exhibit integer and half-integer quantisation.
Due to the fast development in communication technology and the emerging usage of Internet of Things (IoT) devices that produce a huge amount of data, the fifth generation (5G) mobile network is ...introduced to support this development. This mobile network can provide many advanced communication features in cellular phones. But unfortunately, this technology faces many challenges. One of its defective challenges is the management of a massive number of devices running different services, so Software Defined Network (SDN) is proposed as a key technology to overcome this drawback. SDN architecture provides higher flexibility, scalability, cost-effectiveness, and energy efficiency in 5G mobile networks. There are usually different architectures for the SDN control plane. We study some of these architectures, and we conciliate the usage of Logically Centralized-Physically Distributed (LC-PD) controller management architecture in 5G networks. This architecture enables providing higher throughput, and lower latency compared to other control plane architectures. In this paper, we focus on the demonstration that the LC-PD control plane architecture improves communication efficiency and the Quality of Services (QoS) of running internet services in the 5G mobile network. We use the Mininet-WIFI emulator in our simulation tests. Our conducted simulations show that employing the LC-PD control plane architecture in 5G networks enhances the QoS of Internet services compared to other SDN implementations.
The progress in biomedical sensors, Internet of Things technologies, big data, cloud computing, and artificial intelligence is leading the development of e-health medical systems, offering a range of ...new and innovative services. One such service is remote patient monitoring, where medical professionals are able to collect and examine a patient’s medical data remotely. Of course, in these systems, security and privacy are of utmost importance and we need to verify the identities of system users before granting them access to sensitive patient-related data. To this end, several authentication protocols have been recently designed specifically for e-health systems. We survey several of these protocols and report on flaws and shortcomings we discovered. Moreover, we propose an authentication protocol that enables a medical professional and the network of sensors used by a patient to authenticate each other and share a cryptographic key to be used for security in a communication session. The protocol also enables the dynamic assignment of patients to doctors in order to control access to patients’ data. We perform a security analysis of the protocol both formally, using the ProVerif protocol analysis tool, and informally, demonstrating its security features. We show that our protocol achieves mutual authentication, secret key establishment, forward secrecy, and anonymity. In terms of performance, the protocol is computationally lightweight, as it relies on symmetric key cryptography. This is demonstrated by comparing the computational cost of our protocol (in terms of execution time) with that of other similar protocols.
In wireless networks, there are two prominent challenges. The first challenge is ensuring that users have opportunities to access channels and request new services. The second challenge is ...maintaining connections for data flows. These challenges are compounded by the occurrence of channel failures, which often occur due to characteristics of radio transmission such as signal attenuation, signal blockage or device and power outages. Channel failures can significantly impact the effectiveness of both the primary and secondary networks. Therefore, it becomes crucial to prioritize retainability which denotes the need to maintain uninterrupted user connections even during network disruptions. This paper proposes an analytical model that evaluates performance of cognitive radio networks in the context of random channel failure rates. Additionally, the dynamic channel reservation (DCR) scheme is introduced. It can be integrated into dynamic spectrum access (DSA) strategies. This integration aims to give priority to existing services over requests from users to provide cognitive networks with more opportunities to allocate idle channels or maintain their current services. Moreover, the cost functions for both the primary user (PU) and the secondary user (SU) are calculated. This calculation considers the failure rate specifically in either reserved channels (RCN) or non-reserved channels (N-RCN) to meet different performance requirements. The results show a decrease in the SUs cost function, which guarantees that the quality of service (QoS) requirements for the PU are fulfilled. Importantly, this reduction in SU cost leads to an enhancement in SU channel availability or throughput when compared to previous models.
Islamic environmental ethics Rizk, Riham R.
Journal of Islamic accounting and business research,
09/2014, Letnik:
5, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Purpose
To elaborate and discuss key Islamic principles of relevance to environmental ethics and sustainability agendas and reflect on implications for the operations of Islamic Financial ...Institutions (IFIs)
Design/methodology/approach
An exploration of the tenets of environmental sustainability enshrined in Islamic Shariah through a review of key Islamic texts and relevant prior literature.
Findings
The Islamic approach to the environment is holistic and unequivocal. Qur'anic verses describing nature and natural phenomena outnumber verses dealing with commandments and sacraments. Centrality of the environment in the Shari’ah and the Islamic injunction to command right and forbid wrong, are suggestive of an affirmative sustainability agenda for Islamic Financial Institutions.
Practical implications
Implications and opportunities for corporate managers, environmental movements, and policy makers.
Originality/value
By encouraging Muslim engagement in Ijtihad contribute to conceptual development within Islam. It will also be of value to accountability and ecology researchers seeking a better understanding of ecological practices and the internal histories of religions.
Coronary artery aneurysms that occur in 25% of untreated Kawasaki disease (KD) patients may remain clinically silent for decades and then thrombose resulting in myocardial infarction. Although KD is ...now the most common cause of acquired heart disease in children in Asia, the United States, and Western Europe, the incidence of KD in Egypt is unknown. We tested the hypothesis that young adults in Egypt presenting with acute myocardial ischemia may have coronary artery lesions because of KD in childhood. We reviewed a total of 580 angiograms of patients ≤40 years presenting with symptoms of myocardial ischemia. Coronary artery aneurysms were noted in 46 patients (7.9%), of whom 9 presented with myocardial infarction. The likelihood of antecedent KD as the cause of the aneurysms was classified as definite (n = 10), probable (n = 29), or equivocal (n = 7). Compared with the definite and probable groups, the equivocal group had more traditional cardiovascular risk factors, smaller sized aneurysms, and fewer coronary arteries affected. In conclusion, in a major metropolitan center in Egypt, 6.7% of adults aged ≤40 years who underwent angiography for evaluation of possible myocardial ischemia had lesions consistent with antecedent KD. Because of the unique therapeutic challenges associated with these lesions, adult cardiologists should be aware that coronary artery aneurysms in young adults may be because of missed KD in childhood.
Obstructive sleep apnea (OSA) is accompanied by different metabolic disorders and is linked with a heightened incidence of cardiovascular diseases and death. The information actively engaged in ...relating obstructive sleep apnea and dyslipidemia is quite uncertain.
This research intended to determine the correlation between obstructive sleep apnea severeness and lipid profile abnormalities. Our study involved 120 cases diagnosed with OSA, who came to the chest department: at Benha University Hospital from September 2021 to December 2022. Included patients indicated for polysomnography because of suspected sleep-breathing disorders. Full history and clinical examination, and full polysomnography and blood samples for lipid profile, were done for all the cases.
Results
A total of 120 patients were involved in the study. Most cases were severe OSA (70%). The mean age in severe obstructive sleep apnea was 44.04 years with
SD
9.49, Males were 92.9% in severe OSA, and the mean BMI in severe OSA was 36.63 with
SD
7.79. LDL was positively correlated with AHI and DI (significantly); triglycerides were positively correlated with AHI, DI, and min oxygen saturation (significantly); and HDL was negatively correlated with AHI and DI significantly. Among lipid profile variables, LDL was the most predictor for AHI severity.
Conclusion
Lipid abnormalities are associated with OSA severity. Patients diagnosed with obstructive sleep apnea should be screened for lipid profile to correct any abnormality, hoping to prevent their harmful effects.
Background and Aim: The exchange of oxygen and carbon dioxide (CO2) in the incubator plays a key role in embryonic development and hatching. This study aimed to study the effect of non-ventilated ...(NV) intervals during the early stage of embryonic development on the hatching process.
Materials and Methods: Hatching eggs (n = 7200) were equally divided into four treatment groups and incubated in four incubators. The first group was incubated in normal ventilated condition (V) during the setting phase of incubation. Ventilation holes of the three remaining incubators were closed for the first 3, 6, and 9 days and termed as NV groups (NV1, NV2, and NV3, respectively). A gradual increase in CO2 was allowed for NV groups, followed by opening the incubator holes to permit ventilation throughout the rest of the incubation periods.
Results: Obtained results demonstrated that CO2 concentration gradually increased up to 0.19% for the NV1 group, 0.41% for the NV2 group, and 0.90% for the NV3 group, while CO2 concentration remained at 0.08% during the first 9 days of incubation in the V group. Albumen pH was lowered for all NV groups. The highest hatchability percentage was recorded for NV3 followed by NV2 and NV1 groups. All NV groups represented earlier and narrower spread of hatch and higher hatched chick weight. Embryos and hatched chicks in the NV groups had higher hormonal levels of thyroxin and corticosterone.
Conclusion: All non-ventilation periods had positive effects on narrowing the spread of hatch, increasing hatched chick weight and hatchability percentage compared to the normal V condition. Furthermore, the non-ventilation throughout the first 9 days of incubation yielded the best hatching results.
Keywords: albumen pH, carbon dioxide, embryonic hormones, hatchability, non-ventilation.
This work is concerned with the calibration of the HPGe detector used in flowing sample neutron activation analysis technique. The optimum counting configuration and half-life based correction ...factors have been estimated using Monte Carlo computer simulations. Depending on detection efficiency, sample volume and flow type around the detector, the optimum geometry was achieved using 4 mm diameter hose rolled in spiral shape around the detector. The derived results showed that the half-life based efficiency correction factors are strongly dependent on sample flow rate and the isotope half-life.
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