Wideband high gain metasurface-based 4T4R MIMO antenna with highly isolated ports for sub-6 GHz 5G applications.

This study presents the design of four 178 × 178  (mm) 2 wideband, high gain, highly efficient metasurface-based 4T4R MIMO (Multiple-Input Multiple-Output) antennas with highly isolated ports, covering the middle and a portion of the upper bands of the sub 6 GHz 5G frequency spectrum for 5G-based systems, such as IoT (Internet of Things) applications, vehicular communications (e.g., rooftop antennas of cars or trains), smart industries (e.g., farms and factories). The radiating elements of these antennas use the aperture-coupled feeding technique with a dumbbell-shaped slot, a truncated square patch with two U-shaped slots, and a metasurface layer. The proposed MIMO structures place four identical radiating elements like a 2 × 2 matrix with 90 ∘ successive rotations to produce orthogonal electromagnetic waves, improving the isolation between ports. Six-millimeter spaces are added between these elements, and two vertical and horizontal strip slots are carved on the ground as the decoupling structure to decrease the mutual coupling. Simulation results show that Antenna_1, Antenna_2, and Antenna_3 achieve gain values of 6.2 to 9.4 dBi, 8.2 to 11.6 dBi, 6.2 to 9.5 dBi, below - 35, - 25, and - 33 isolation and almost 10 dB diversity gain from 2.8 to 4.7 GHz, 2.8 to 4.5 GHz, and 2.7 to 4.9 GHz, respectively. As a prototype, Antenna_4 is manufactured, and measurements are performed. It achieves 6.28 to 10.45 dBi gain values, below - 23 dB isolation, and 0.001 envelope correlation coefficient over 2.7 to 4.3 GHz. The results confirm that the proposed MIMO antennas are compatible with the 5G essential requisites.

High oxidation state enabled by plated Ni-P achieves superior electrocatalytic performance for 5-hydroxymethylfurfural oxidation reaction.

Electrochemical 5-hydroxymethylfurfural oxidation reaction (HMFOR), as a clean biorefinery process, promotes a circular economy with value-added products. In HMFOR, the intrinsic catalytic activity and charge transfer mechanisms are crucial. Herein, nickel, co-deposited with phosphorus (Ni-P), attains superior electrocatalytic performance compared with Ni and its oxyhydroxides for the HMFOR. Such electrocatalytic activity of the Ni-P catalyst is attributed to the high oxidation state of surface Ni species, supported by the bulk Ni-P component. An unprecedented charge storing capacity enabled by the bulk Ni-P material maintains the spontaneous reaction between HMF and Ni3+ species to achieve a current density of 10 mA/cm2 normalized by the electrochemical active surface area at a low potential of 1.42 V vs RHE, reaching a 97% Faradaic efficiency toward 2,5-furandicarboxylic acid. This work, for the first time, sheds light on the importance of the electrode bulk material by showcasing the HMFOR via the Ni-P catalyst incorporating a charge-holding bulk component.

Estimation of stress-strength reliability for Marshall-Olkin distributions based on progressively Type-II censored samples.

We are mainly interested in estimating the stress-strength parameter, say R , when the parent distribution follows the well-known Marshall-Olkin model and the accessible data has the form of the progressively Type-II censored samples. In this case, the stress-strength parameter is free of the base distribution employed in the Marshall-Olkin model. Thus, we use the exponential distribution for simplicity. The maximum likelihood methods as well as some Bayesian approaches are used for the estimation purpose. The corresponding estimators of the latter approach are obtained by using Lindley's approximation and Gibbs sampling methods since the Bayesian estimator of R cannot be obtained as an explicit form. Moreover, some confidence intervals of various types are derived for R and then compared via a Monte Carlo simulation. Finally, the survival times of head and neck cancer patients are analyzed by two therapies for illustrating purposes.

The Relationship between Prevention and Panic from COVID-19, Ethical Principles, Life Expectancy, Anxiety, Depression and Stress.

The present study aims to assess the relationship between prevention and panic from COVID-19, ethical principles, life expectancy, anxiety, depression, and stress in auditors and financial managers of small- and medium-sized Iraqi firms. In other words, this paper seeks to answer the question of whether different types of prevention and panic from COVID-19 can enhance the ethical principles, life expectancy, anxiety, depression, and stress, or not. The study method is practical in its objective and descriptive survey procedure. The study's statistical population includes 185 employed auditors in audit firms, and 215 financial managers of small- and medium-sized Iraqi firms were selected as a sample of the study using the Cochran Sampling Method. In this paper, PLS tests are used to assess the effect of independent variables on the dependent variable. The results indicate no significant relationship between prevention from COVID-19 and ethical principles and life expectancy. However, the association between prevention from COVID-19 and anxiety, depression, and stress, and between panic from COVID-19 and ethical principles, life expectancy, anxiety, depression, and stress is positive and significant. The higher the panic from COVID-19, the more ethical principles, life expectancy, anxiety, depression, and stress. Since no study has been carried out so far on the effect of prevention and panic from COVID-19, ethical principles, life expectancy, depression, and stress in Iraqi firms, the present study results can provide valuable information and contribute to the development of science and knowledge.

Correlation of Serum Levels of Interleukine-16, CCL27, Tumor Necrosis Factor-related Apoptosis-inducing Ligand, and B-cell Activating Factor with Multiple Sclerosis Severity.

The pathogenic roles of Interleukine-16 (IL-16), CCL27, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and B-cell activating factor (BAFF) has been shown in some autoimmune and inflammatory diseases. We aimed to correlate the circulatory changes of such factors with the severity of disease in patients with multiple sclerosis (MS). This case-control study was conducted on 84 MS patients and 83 healthy controls. We measured the serum levels of IL-16, CCL27, TRAIL, and BAFF in all participants by enzyme-linked immune sorbent assay. Using the expanded disability status scale (EDSS), we evaluated the severity of MS. Finally, we assessed the correlation between serum levels of such factors with the severity of MS. We found increased serum levels of CCL27, IL-16, and BAFF in patients with MS compared to those in healthy subjects. However, no difference was found in serum levels of TRAIL between the patients and controls. In addition, a significant positive correlation between serum levels of CCL27, IL-16, TRAIL, and BAFF with disease severity according to EDSS score was determined. We showed higher serum levels of CCL27, BAFF, TRAIL, and IL-16 in MS patients with more severe disabilities than mild forms. Such finding may represent their contribution to the pathogenesis of MS. Blocking such molecules may yield new treatments for MS.

Evaluating prediction of COVID-19 at provincial level of South Africa: a statistical perspective.

What is the impact of COVID-19 on South Africa? This paper envisages to assist researchers in battling of the COVID-19 pandemic focusing on South Africa. This paper focuses on the spread of the disease by applying heatmap retrieval of hotspot areas, and spatial analysis is carried out using the Moran index. For capturing spatial autocorrelation between the provinces of South Africa, the adjacent as well as the geographical distance measures are used as weight matrix for both absolute and relative counts. Furthermore, generalized logistic growth curve modelling is used for prediction of the COVID-19 spread. We expect this data-driven modelling to provide some insights into hotspot identification and timeous action controlling the spread of the virus.

A Synergetic R-Shiny Portal for Modeling and Tracking of COVID-19 Data.

The purpose of this paper is to introduce a useful online interactive dashboard (https://mahdisalehi.shinyapps.io/Covid19Dashboard/) that visualize and follow confirmed cases of COVID-19 in real-time. The dashboard was made publicly available on 6 April 2020 to illustrate the counts of confirmed cases, deaths, and recoveries of COVID-19 at the level of country or continent. This dashboard is intended as a user-friendly dashboard for researchers as well as the general public to track the COVID-19 pandemic, and is generated from trusted data sources and built in open-source R software (Shiny in particular); ensuring a high sense of transparency and reproducibility. The R Shiny framework serves as a platform for visualization and analysis of the data, as well as an advance to capitalize on existing data curation to support and enable open science. Coded analysis here includes logistic and Gompertz growth models, as two mathematical tools for predicting the future of the COVID-19 pandemic, as well as the Moran's index metric, which gives a spatial perspective via heat maps that may assist in the identification of latent responses and behavioral patterns. This analysis provides real-time statistical application aiming to make sense to academic- and public consumers of the large amount of data that is being accumulated due to the COVID-19 pandemic.

Numerical status of CD4(+)CD25(+)FoxP3(+) and CD8(+)CD28(-) regulatory T cells in multiple sclerosis.

OBJECTIVES: Regulatory T cells, including CD4+CD25+Fox3+ and CD8+CD28- cells play an important role in regulating the balance between immunity and tolerance. Since multiple sclerosis is an inflammatory autoimmune disease, regulatory T cells are considered to be involved in its pathogenesis. In this study, we investigated the circulatory numbers of the two mentioned types of regulatory T cells and also their association with different clinical characteristics in 84 multiple sclerosis patients. MATERIALS AND METHODS: 84 patients with multiple sclerosis and 75 normal individuals were studied. Demographic and clinical information of all participants were collected via questionnaire and clinical examination as well as MRI. The peripheral blood frequency of two different subgroups of regulatory T cells (CD4+ CD25+Foxp3+ and CD8+CD28- cells) were analyzed by flow cytometry using anti-human antibodies conjugated with CD4-FITC / CD25-PE/Foxp3-PE-Cy5, CD3-PE/CD8a-PE-Cy5/CD28-FITC. RESULTS: The frequency of CD4+CD25+Foxp3+ cells in multiple sclerosis patients was significantly less than that in healthy controls (P=0.006) and in mild forms less than that in sever forms (P=0.003). There was not any correlation between the frequency of regulatory T cells and different clinical variables. CONCLUSION: Our results showed that the number of CD4+CD25+Foxp3+ cells decreases significantly in multiple sclerosis patients, which probably shows the regulatory role of these cells in multiple sclerosis.