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Frequency scanning is a unique feature of periodic leaky-wave antennas (P-LWAs), according to which the main beam scans space upon frequency control. However, one-dimensional (1D) and two-dimensional P-LWAs are capable of scanning space only in a single plane, with a fan beam and a pencil beam, respectively. Here, we explore the possibility of achieving full-space frequency-scanning coverage with 2D P-LWA leveraging multiple space harmonics. Furthermore, we propose a design of 2D P-LWAs with series feeding network, which has 4 ports and capable of covering the full-space. Finally, the results are discussed and plotted based on analytical dispersion diagrams and array factor theory.

Abstract Freeze-thaw cycles are a major cause for destabilizing pavements in cold regions. Among countermeasures for freeze-thaw damages, use of geocells to reinforce pavement bases is an effective solution in practice. However, as opposed to widespread applications, research concerning freeze-thaw behavior of geocell-reinforced bases is limited, probably due to a lack of proper devices for conducting experimental tests. This paper presents a new model-test device capable of performing both freeze-thaw tests and plate loading tests on geocell-reinforced soils. A thermodynamic numerical model was developed to assist with the design of freeze-thaw component of the device, while the design of plate loading component was developed by referring to features of existing devices. Eleven tests were run on geocell-reinforced and unreinforced sands to confirm the effectiveness of the proposed device. The test results showed the device successfully provided vertical heat transfer in sands during freeze and thaw. After five freeze-thaw cycles, geocells reduced peak frost heave and thaw settlement of sands by 18% and 34%, respectively, and increased the stiffness and bearing capacity by 40% and 253%, respectively. It was found a temperature drop occurred at the interface between cooling plate and sands, which was due to the existence of thermal contact resistance.

Abstract A simple geometry is used to compare several of the available Monte Carlo software codes for radiation transport. EGSnrc, Geant4 and MCNP5 are all used to calculate the photon fluence produced from electrons incident on a copper target. Four energies for the isotropic point source are chosen to simulate the average and maximum emission energies of 32 P and 90 Y: (0.7, 1.71) MeV and (0.93, 2.28) MeV, respectively. The energy deposition in the copper target, the electron current at the target and the computational efficiency are also calculated. EGSnrc is found to be the only self-consistent code when comparing results calculated using the default transport parameters of the condensed history mode with those calculated in the single scattering mode.

Security is an interesting area, one in which we may well be guilty of misunderstanding the very people we are working for whilst trying to protect them. It is often said that people (users) are a weak link in the security chain. This may be true, but there are nuances. In this chapter, the authors discuss some of the work they have done and are doing to help users understand their information and device security and make informed, guided, and responsible decisions. This includes Device Comfort, Annoying Technologies, and Ten Commandments for designers and implementers of security and trust systems. This work is exploratory and unfinished (it should in fact never be finished), and this chapter presents a step along the way to better security users.

This article examines aspects related to the dystopic consumption and production of the musical and performance art form known as black metal. Steeped in anti-Christian motifs, surrounded by a history of violence and brutal imagery, black metal is an extreme metal art form that has been growing steadily in popularity throughout Europe, South America, and the United States. We first examine black metal culture through the eyes of both artists and consumers, using mixed qualitative methodologies. Thereafter, we derive specific theoretical interpretations from the black metal subculture that are predicated on the emerging themes of signification, identity transformation, xenophobia, and a reconstructed mythology that all point to what we present as a dystopian consumption model. The model demonstrates how dystopia, in context, is at the heart of the symbiotic relationship between consumers and producers and is encapsulated by a specific set of processes and overarching conditions. Implications and relationships to utopian models are discussed.

Abstract Background Fibrosis regression has been associated with nucleoside analogue (NA) treatment in chronic hepatitis B (CHB) patients. Although non-invasive fibrosis markers have been evaluated in CHB, their utility for monitoring on-treatment histologic regression has not been evaluated. Aims To characterize improvements in disease severity and the utility of non-invasive biomarkers in CHB NA treated patients. Methods Histology, labs, AST-to-platelet ratio index, and Fibrosis-4 (Fib-4) from treatment-naive CHB patients were evaluated at baseline and longitudinally. Relative change from baseline to various time points during treatment were evaluated. Correlative analysis of APRI and Fib-4 with histology was performed longitudinally. Results 80 CHB patients (84% male, median age 45 (IQR 32, 54)) with histology up to 17 years (median 6(IQR 3.9, 8.0)) years were studied. Median baseline Ishak fibrosis was 3 (IQR 2, 4), histologic activity index (HAI) inflammation was 9 (IQR 7, 11), and AUROC of fibrosis markers for detecting cirrhosis (Ishak ≥ 5) was >0.64. HAI improved at a rate of 54% during year 1 and 37% in year 2, both greater than in the remaining follow-up periods. Within the first year, fibrosis improved by 35%, greater than all other time periods. Non-invasive biomarkers began to correlate with histology beyond 4 years (APRI: 4–6 years: r = 0.33, p = 0.03; ≥6 years: r = 0.41, p = 0.009; Fib-4: ≥6 years: r = 0.35, p = 0.03). Conclusion Early dynamic changes in histology occur in CHB patients on NA followed by linear improvements. Non-invasive fibrosis biomarkers do not capture these dynamic changes and may demonstrate clinical utility beyond 4 years of treatment.

Background Child survival initiatives historically prioritized efforts to reduce child morbidity and mortality from infectious diseases and maternal conditions. Little attention has been devoted to paediatric injuries in resource‐limited settings. This study aimed to evaluate the demographics and outcomes of paediatric injury in a sub‐Saharan African country in an effort to improve prevention and treatment. Methods A prospective trauma registry was established at the two university teaching campuses of the University of Rwanda to record systematically patient demographics, prehospital care, initial physiology and patient outcomes from May 2011 to July 2015. Univariable analysis was performed for demographic characteristics, injury mechanisms, geographical location and outcomes. Multivariable analysis was performed for mortality estimates. Results Of 11 036 patients in the registry, 3010 (27·3 per cent) were under 18 years of age. Paediatric patients were predominantly boys (69·9 per cent) and the median age was 8 years. The mortality rate was 4·8 per cent. Falls were the most common injury (45·3 per cent), followed by road traffic accidents (30·9 per cent), burns (10·7 per cent) and blunt force/assault (7·5 per cent). Patients treated in the capital city, Kigali, had a higher incidence of head injury (7·6 per cent versus 2·0 per cent in a rural town, P < 0·001; odds ratio (OR) 4·08, 95 per cent c.i. 2·61 to 6·38) and a higher overall injury‐related mortality rate (adjusted OR 3·00, 1·50 to 6·01; P = 0·019). Pedestrians had higher overall injury‐related mortality compared with other road users (adjusted OR 3·26, 1·37 to 7·73; P = 0·007). Conclusion Paediatric injury is a significant contributor to morbidity and mortality. Delineating trauma demographics is important when planning resource utilization and capacity‐building efforts to address paediatric injury in low‐resource settings and identify vulnerable populations. This study evaluated the demographics and outcomes of paediatric injury in Rwanda through a prospective trauma registry to inform capacity‐building for prevention and treatment. Patients treated in the capital city had a higher incidence of head injury and a higher overall injury‐related mortality than those in a rural town. Pedestrians had higher overall injury‐related mortality compared with other road‐users. Falls and road traffic accidents significant contributors to pediatric injury in Rwanda

In the last century, we have passed two severe pandemics; the 1957 influenza (Asian flu) pandemic and the 1918 influenza (Spanish flu) pandemic with a high fatality rate. In the last few months, we have been again facing a new epidemic (COVID-19), which is a frighteningly high-risk disease and is globally threatening human lives. Among all attempts and presented solutions to tackle the COVID-19, a publicly available dataset of radiological imaging using chest radiography, also called chest X-ray (CXR) images, could efficiently accelerate the detection process of patients infected with COVID-19 through presented abnormalities in their chest radiography images. In this study, we have proposed a deep neural network (DNN), namely RAM-Net, a new combination of MobileNet with Dilated Depthwise Separable Convolution (DDSC), Residual blocks, and Attention augmented convolution. The network has been learned and validated using the COVIDx dataset, one of the most popular public datasets comprising the chest X-ray (CXR) images. Using this model, we could accurately identify the positive cases of COVID-19 viral infection while a new suspicious chest X-ray image is shown to the network. Our network’s overall accuracy on the COVIDx test dataset was 95.33%, with a sensitivity and precision of 92% and 99% for COVID-19 cases, respectively, which are the highest results on the COVIDx dataset to date, to the best of our knowledge. Finally, we performed an audit on RAM-Net based on the Grad-CAM’s interpretation to demonstrate that our proposed architecture detects SARS-CoV-2 (COVID-19) viral infection by focusing on vital factors rather than relying on irrelevant information.