31 research outputs found
Advanced Space-Time Coding: Near-Capacity Sphere-Packing, Multi-Functional MIMOs and Cooperative Space-Time Processing
No full textNear-Capacity Three-Stage Turbo Detection of Irregular Convolutional Coded Joint Sphere-Packing Modulation and Space-Time Coding
No full textNear-capacity wireless transceivers and cooperative communications in the MIMO era: evolution of standards, waveform design, and future perspectives
Get PDFClassic Shannon theory suggests that the achievable channel capacity increases logarithmically with the transmit power. By contrast, the MIMO capacity increases linearly with the number of transmit antennas, provided that the number of receive antennas is equal to the number of transmit antennas. With the further proviso that the total transmit power is increased proportionately to the number of transmit antennas, a linear capacity increase is achieved upon increasing the transmit power, which justifies the spectacular success of MIMOs. Hence we may argue that MIMO-aided transceivers and their cooperation-assisted distributed or virtual MIMO counterparts constitute power-efficient solutions. In a nutshell, since the conception of GSM in excess of three orders of magnitude bit-rate improvements were achieved in three decades, which corresponds to about a factor ten for each decade, because GSM had a data rate of 9.6 Kb/s, while HSDPA is capable of communicating at 13.7 Mb/s. However, the possible transmit power reductions remained more limited, even when using the most advanced multistage iterative detectors, since the required received signal power has not been reduced by as much as 30 dB. This plausible observation motivates the further research of advanced cooperation-aided wireless MIMO transceivers, as detailed in this treatis
Nurse Practitioner: Is It Time to Have a Role in Saudi Arabia?
No full textLow recruitment of Saudi nationals into the nursing profession, coupled with a growing population, has led to a severe nursing shortage in Saudi Arabia, particularly of nurses with advanced qualifications in clinical nursing. While the role of nurse practitioner has been successfully integrated into the healthcare systems of the U.S., Canada, the UK and Australia for decades, the advanced practice registered nurse (APRN), which includes nurse practitioners and clinical nursing specialists, is still not being implemented effectively in Saudi Arabia due to a variety of regulatory, institutional and cultural barriers. The author looks at some of those barriers and offers recommendations of how they might be overcome. Given that in many parts of the world, nurse practitioners are considered an essential component to meeting healthcare demands, the author considers the question of whether APRNs can find a role in Saudi Arabia’s healthcare system
A spatio-temporal agent-based approach for modeling the spread of zoonotic cutaneous leishmaniasis in northeast Iran
Get PDFBackground: Zoonotic cutaneous leishmaniasis (ZCL) is a neglected tropical disease worldwide, especially the Middle East. Although previous works attempt to model the ZCL spread using various environmental factors, the interactions between vectors (Phlebotomus papatasi), reservoir hosts, humans, and the environment can affect its spread. Considering all of these aspects is not a trivial task. Methods: An agent-based model (ABM) is a relatively new approach that provides a framework for analyzing the heterogeneity of the interactions, along with biological and environmental factors in such complex systems. The objective of this research is to design and develop an ABM that uses Geospatial Information System (GIS) capabilities, biological behaviors of vectors and reservoir hosts, and an improved Susceptible-Exposed-Infected-Recovered (SEIR) epidemic model to explore the spread of ZCL. Various scenarios were implemented to analyze the future ZCL spreads in different parts of Maraveh Tappeh County, in the northeast region of Golestan Province in northeastern Iran, with alternative socio-ecological conditions. Results: The results confirmed that the spread of the disease arises principally in the desert, low altitude areas, and riverside population centers. The outcomes also showed that the restricting movement of humans reduces the severity of the transmission. Moreover, the spread of ZCL has a particular temporal pattern, since the most prevalent cases occurred in the fall. The evaluation test also showed the similarity between the results and the reported spatiotemporal trends. Conclusions: This study demonstrates the capability and efficiency of ABM to model and predict the spread of ZCL. The results of the presented approach can be considered as a guide for public health management and controlling the vector populationFigure not available: see fulltext.. © 2020, The Author(s)
The efficacy of topical treatments for acanthosis nigricans: a systematic review of randomized controlled trials
Get PDFBackgroundAcanthosis nigricans (AN) is a skin disorder marked by darkening and thickening of the skin, often linked to metabolic abnormalities. This systematic review of randomized controlled trials (RCTs) assesses the comparative effectiveness and tolerability of different topical treatment options of AN, aiming to determine the most suitable therapeutic strategies.MethodsA comprehensive literature search was conducted across PubMed, Scopus, ClinicalTrials.gov, Web of Science, and the Cochrane Library, yielding 6,407 studies. After screening and a full-text review, seven randomized controlled trials (n = 268) assessed topical urea (10–20%), tretinoin (0.025–0.05%), salicylic acid (10%), and chemical peels such as glycolic acid (35–70%) and trichloroacetic acid (15%) over 8 weeks to 2 months, primarily on the neck and axilla. Outcomes included melanin and erythema indices (M/E), ANASI/ANSC scores, Investigator’s and Participant’s Global Evaluation (IGE/PGE), and adverse events.ResultsUrea demonstrated significant efficacy in reducing erythema, particularly at higher concentrations (20%), with mild adverse events such as stinging or irritation. Tretinoin was the most effective for reducing dark pigmentation, especially on the neck, and patients were more satisfied with it than with glycolic acid. Salicylic acid (10%) gave results similar to urea, with only mild side effects like dryness or peeling. Trichloroacetic acid (15%) peel was more effective than glycolic acid (35%) peel, both in skin improvement and patient satisfaction after 8 weeks. Overall, side effects with all treatments were mild and went away on their own.ConclusionBoth urea and tretinoin are effective treatments for AN, choice of therapy should be individualized tretinoin for predominant hyperpigmentation, urea for erythema or lower irritation tolerance, salicylic acid as a tolerable alternative, and TCA peel when stronger procedural options are suitable glycolic peel showed more modest effects.Systematic review registrationProspero registration number: (CRD42023444441); https://www.crd.york.ac.uk/PROSPERO/view/CRD42023444441
Wireless myths, realities, and futures: from 3G/4G to optical and quantum wireless
No full textThis paper evaluates both the operational third-generation (3G) as well as the emerging fourth-generation (4G) wireless systems and investigates new technologies that might transpire and change things in the future.<br/
An Intuitive Authoring System for a Personalised, Social, Gamified, Visualisation-supporting e-learning System
Get PDFAdaptive Educational Hypermedia (AEH) offers more advanced personalisation and customisation features to the field of e-learning compared to the outdated static systems (where every learner is given the same set of learning materials). AEH can improve the usability of hypermedia, by providing a model of various qualities of a learner and apply this information to adapt the content and the navigation to the requirements of the learner. However, authoring adaptive materials is not a simple task, as an author may be pressed for time, or simply lack the skills needed, to create new adaptive materials from scratch, and thus any improvements in the reuse of adaptation specification (application of adaptive behaviour rules) is a major help in the authoring process. The aim of this study is thus to expand a personalised, social, gamified, visualisation-supporting e-learning system based on Adaptive Educational Hypermedia (Topolor), by implementing an easy-to-use, intuitive authoring tool and to evaluate it with experts in the field as well as high-school teachers
Near-capacity iterative decoding of binary self-concatenated codes using soft decision demapping and 3-D EXIT charts
Get PDFIn this paper 3-D Extrinsic Information Transfer (EXIT) charts are used to design binary Self-Concatenated Convolutional Codes employing Iterative Decoding (SECCC-ID), exchanging extrinsic information with the soft-decision demapper to approach the channel capacity. Recursive Systematic Convolutional (RSC) codes are selected as constituent codes, an interleaver is used for randomising the extrinsic information exchange of the constituent codes, while a puncturer helps to increase the achievable bandwidth efficiency. The convergence behaviour of the decoder is analysed with the aid of bit-based 3-D EXIT charts, for accurately calculating the operating EbN0 threshold, especially when SP based soft demapper is employed. Finally, we propose an attractive system configuration, which is capable of operating within about 1 dB from the channel capacity
Comprehensive Biological Potential, Phytochemical Profiling Using GC-MS and LC-ESI-MS, and In-Silico Assessment of Strobilanthes glutinosus Nees: An Important Medicinal Plant
No full textPlants of the genus Strobilanthes have notable use in folklore medicines as well as being used for pharmacological purposes. The present work explored the biological predispositions of Strobilanthes glutinosus and attempted to accomplish a comprehensive chemical profile through GC-MS of different fractions concerning polarity (chloroform and n-butanol) and LC-ESI-MS of methanolic extract by both positive and negative ionization modes. The biological characteristics such as antioxidant potential were assessed by applying six different methods. The potential for clinically relevant enzyme (α-amylase, α-glucosidase, and tyrosinase) inhibition was examined. The DPPH, ABTS, CUPRAC, and FRAP results revealed that the methanol fraction presented efficient results. The phosphomolybdenum assay revealed that the n-hexane fraction showed the most efficient results, while maximum metal chelation potential was observed for the chloroform fraction. The GC-MS profiling of n-butanol and chloroform fractions revealed the existence of several (110) important compounds presenting different classes (fatty acids, phenols, alkanes, monoterpenes, diterpenes, sesquiterpenoids, and sterols), while LC-ESI-MS tentatively identified the presence of 44 clinically important secondary metabolites. The n-hexane fraction exhibited the highest potential against α-amylase (497.98 mm ACAE/g extract) and α-glucosidase (605.85 mm ACAE/g extract). Significant inhibitory activity against tyrosinase enzyme was displayed by fraction. Six of the prevailing compounds from the GC-MS study (lupeol, beta-amyrin, stigmasterol, gamma sitosterol, 9,12-octadecadienoic acid, and n-hexadecanoic acid) were modelled against α-glucosidase and α-amylase enzymes along with a comparison of binding affinity to standard acarbose, while three compounds identified through LC-ESI-MS were docked to the mushroom tyrosinase enzyme and presented with significant biding affinities. Thus, it is assumed that S. glutinosus demonstrated effective antioxidant and enzyme inhibition prospects with effective bioactive molecules, potentially opening the door to a new application in the field of medicine
