This paper introduces a compact modified semi-circular monopole ultra-wideband (UWB) antenna. A compact antenna size (4.3 × 3.4 cm2) compared to the typical coplanar waveguide (CPW) circular monopole antenna (5.5 × 4 cm2) is achieved. The proposed antenna is completely proven for UWB communication performance. The antenna is matched over 8.4 GHz bandwidth (2.2–10.6 GHz), with reflection coefficient lower than −10 dB over the band. Matching bandwidth is verified through simulation and measurements of VSWR. Efficient power radiation over the band is proven through radiation efficiency. Radiation efficiency is not lower than 81% at the upper end of the band. Omnidirectional characteristics are proven through, firstly, measured transfer function magnitude at three different configurations, Face-to-Face, Face-to-Side, and Side-by-Side (all frequencies at different orientations), and, secondly, measured radiation pattern at three selected frequencies that span the bandwidth (all orientations at different frequencies). Moreover, the ability of the antenna to support, as narrow pulses as, 0.25 ns omnidirectionally is proven through detailed study for time response. Antenna transfer function is measured for magnitude and phase. Then, a first-order Raeighly pulse, that fulfils the FCC mask for emission restrictions, is applied at the terminals of a UWB system of the proposed UWB antenna. Finally, the output, barely distorted, normalized, pulse is compared to the input pulse.
Twenty-six species of aquatic hyphomycetes were isolated from woody sources (unidentified wood segments, leaf skeletons and neck of leaves and bark) in the North River Nile (Delta region). Alatospora acuminata, Anguillospora crassa, Flagellaspora penicillioides, Lunulospra curvula, Tetracladium marchalianum and Triscelophorus monosporus were the most common species. Temperature was the highest physico-chemical parameter affecting the aquatic hyphomycetes occurrence. Twelve species of hyphomycetes, isolated from woody substrates, were screened for their ability to produce extracellular lignocellulolytic enzymes on solid media. The enzymes tested included: endoglucanase, endoxylanase, beta-glucosidase, laccase, peroxidase, polyphenoloxidase, tyrosinase and beta-xylosidase. Three species, A. acuminata, F. penicillioides, T. monosporus, were positive for all tested enzymes. Also, A. longissima was positive for all enzymes except lignin-peroxidase. The ability to produce cellulase was 100% for all species while only, four species were positive for lignin-peroxidase. The ability of the species to produce other lignocellulotic enzyme ranged from 50% to 83%. Freshwater hyphomycetes have been shown to produce a rich array of enzymes able to degrade the polysaccharides of plant debris.
Lyophilization is a common unit operation in pharmaceutical manufacturing but is a prolonged vacuum drying process with poor energy utilization. Microwave-assisted vacuum drying has been investigated to accelerate the lyophilization process. However, the literature lacks methodical approaches that consider the lyophilizer, the lyophilizate, the microwave power uniformity, the resulting heat uniformity, and the scalability. We present a microwave-vacuum drying method based on the statistical electromagnetics theory. The method offers an optimum frequency selection procedure that accounts for the lyophilizer and the lyophilizate. The 2.45 GHz frequency conventionally utilized is proven to be far from optimum. The method is applied in a microwave-assisted heating configuration to pharmaceutical excipients (Sucrose and Mannitol) and different myoglobin formulations in a lab-scale lyophilizer. At 18 GHz frequency and 60 W microwave power, the method shows nearly three times speed-up in the primary drying stage of sucrose relative to the conventional lyophilization cycle for typical laboratory batches. The uniformity of the microwave power inside the chamber is controlled within ±1dB. The resulting heating uniformity measured through residual moisture analysis shows 12.7% of normalized standard deviation of moisture level across the batch in a microwave-assisted cycle as opposed to 15.3% in the conventional cycle. Conventional and microwave lyophilized formulations are characterized using solid-state hydrogen-deuterium exchange-mass spectrometry (ssHDX-MS), solid-state Fourier transform infrared spectroscopy (ssFTIR), circular dichroism (CD), and accelerated stability testing (AST). Characterization shows comparable protein structure and stability. Heat and mass transfer simulations quantify further effects of optimal volumetric heating via the high-frequency statistical microwave heating.
Since the onset of the coronavirus pandemic, there have been thousands of articles on the use of metaphor to describe the crisis. A Google search yields more than 7000 hits. Indeed, an avalanche of metaphors has already been used to describe the Covid-19 pandemic. From war and oceanic metaphors to the dreaded phrase ‘ramping up’, the language and images used by politicians, journalists, scientific experts, commentators, artists, comedians, and meme-makers to understand the crisis are not neutral constructs. But far more disappointing than the use of inappropriate or politically incorrect metaphors is the fact that there is no single scholarly article that systematically studies the influence of the pandemic on cognition, especially metaphorical conceptualization. That is, how has the coronavirus pandemic changed the meaning of home, love, Halloween, social media platforms, and so on for us? Technically speaking, how has the crisis triggered, prompted, or simply facilitated the selection and employment of particular conceptual metaphors or their linguistic and non-linguistic manifestations? This article, based on a large-scale corpus of political cartoons, aims to answer that question – how the pandemic itself becomes a metaphor. I show that various different metaphor targets (including WAR, ISRAEL, TURKEY, DONALD TRUMP, BENJAMIN NETANYAHU, ARAB DICTATORS, THE KUWAITI NATIONAL ASSEMBLY, THE JORDANIAN CABINET, THE IRANIAN REGIME, MILITANT GROUPS, POVERTY, RACISM, CALENDAR, CORRUPTION, INJUSTICE, RUMORS, POLITICAL ASSASSINATIONS, THE GLOBE, THE UNION JACK, THE EUROPEAN UNION, THE US FAR RIGHT, THE 50 STARS OF THE AMERCAN FLAG, US-RUSSIAN RELATIONS, HOUSEWIVES, PERSONAL BELONGINGS, LOVE, QURBAN BAYRAM, CHRISTMAS, HALLOWEEN, ARABIC DRAMA, SCHOOL BAG, AWARENESS, and SOCIAL MEDIA COMPANIES such as Facebook, among many others) are all explained with reference to coronavirus-related terms or the source domain of CORONAVIRUS/VACCINATION. The sheer frequency of occurrences of CORONAVIRUS metaphors (a total of 175 out of 497 relevant multimodal cartoons, that is, more than 35%) demonstrates and makes a case for the necessity to examine the effect of context, in particular topical news and physical circumstances, in the cognitive linguistic study of creative metaphor. In short, the results provide initial evidence that new viruses and diseases such as Covid-19 have a negative and significant effect on cognition (or shape societies’ worldviews).
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