bluuebunny/crossref_metadata_2025 huggingface dataset:
Designing Filtering Antennas for 5G Applications
Authors: Stavrakis Adrian K. , Ogbodo Eugene Amobichukwu
Published: May 2021

This chapter aims to serve as an introduction to the integration process of filters and antennas into a single component, a filtering antenna, or filtenna, which is a topic of rising scientific interest and importance in recent years. As most receiving and transmitting devices nowadays call for a smaller footprint, better power management, and simplification of fabrication, this chapter showcases all the steps the reader must take to have a holistic approach to the integration of the aforementioned two components. Therefore, the fundamental principles of antenna, microstrip line, and filter theories are explored, and they are applied to a proof-of-concept patch filtering antenna operating in the S-Band, and at a frequency suitable for allocation to the 5G communications applications, while notable examples from other authors also demonstrate different ways of tackling this domain.
The Role of Artificial Intelligence and Fifth-Generation (5G) Technology in Mitigating Cyber Physical Attacks on Power Systems
Authors: Olusuyi Kehinde Oluwafemi , Olulope Paul Kehinde , Amoran Abiodun Ernest , Peter Eno Edet
Published: May 2021

The present-day electric power system is an evolving cyber-physical system. Researchers and industry players in the energy world continue to deploy new technologies towards making the electric power system a smarter grid. This involves the integration of information, communication, and control technologies into the existing power grid in order to improve its stability, security, and operational efficiency. Reliance of the modern power system's applications such as state estimation, sequential control and data acquisition (SCADA) systems, phasor measurement units (PMUs), etc. on open communication technologies including the internet has exposed the smart grid to various vulnerabilities, threats, and cyber-physical attacks. This chapter seeks to exploit the robust synergy which exists between artificial intelligence (AI) and fifth-generation (5G) technology to mitigate these challenges. A comprehensive review of techniques which have hitherto proven efficient and/or effective in mitigating identified challenges was carried out with a view to availing researchers of future directions.
Application of Steganography for Secure Data Transmission Using Lossless Compression
Authors: Fernandes Kylyn , Gupta Ankit Rishi , Panchal Pratik , Mangrulkar Ramchandra
Published: May 2021

Steganography is the art of hiding messages or files in a way that prevents the detection of the existence of these hidden messages. It encompasses several techniques, including physical methods like invisible ink on paper and digital techniques like hiding text on multimedia files like images and music files. In the modern digital era, steganography has become a useful tool to evade detection and perusal of secret messages. With the advent of social media, it is very easy to encode a message or file onto an image and upload it online for the intended recipients to access, decode, and read or use. In this case of digital steganography of messages or files onto images, an important factor to consider is the effect of image compression on the hidden message. Since most social media and other online image posting websites run some sort of compression, cropping, and other image transformations on the uploaded images, understanding these techniques and their effect on the hidden text can help one choose the most suitable steganography technique to use for a particular use case.
Regional Centrality
Authors: Fontoura M. Paula , Crespo Nuno , Simoes Nadia
Published: May 2021

The theme of regional centrality, more commonly known as accessibility, has been increasingly invoked in recent years, mainly due to a clearer understanding that proximity to the markets is a key determinant of the location of firms. This chapter improves the most standard accessibility index using a decomposition method that allows considering the influence of (1) internal and external factors and (2) economic and geographical aspects. Each component identified has a specific interpretation and allows the identification of policy recommendations, such as the development of the transport and communication networks and active interventions to attract investment. The baseline decomposition method is adjusted in order to incorporate differences in spatial terms among the regional units considered. In order to illustrate the proposed methodology, the authors consider 171 countries. Results lead to the conclusion that the centrality level of the countries analyzed derives from different sources. Therefore, different countries may require different policy interventions to improve their centrality.
China's Geostrategic Approach to Trade in Pursuit of Global Centrality
Authors: Massamba Guy-Maurille
Published: May 2021

The geostrategic approach refers to China's method to rise as global power through worldwide trade expansion and the development of its military and naval capabilities. It creates clusters of countries interlinked as China's trade partners, thus being assets to its global ascent. China's importance in global trade is a function of its partners' behavior embracing its trade mechanism. The edges connecting nodes are multidirectional, implying that countries are as much interested in their China-induced interlinkages as they are in their partnership with China. This results in China's centrality, a quality gained from being dominant in trade partnerships in terms of numbers and significance. This chapter examines the approach, process, and historical, geographic, and behavioral components that China uses in its ascent as central node in the international trade network. It explores how underlying dimensions making China's national character conjointly devise its behavior in global trade.
Evaluation of India's Proposed Regional Trade Agreements With Major Economies Using General Equilibrium Analysis
Authors: Mathur Somesh , Agarwal Naman
Published: May 2021

This chapter attempts to analyze trade effects of India's liberalization with the Association of Southeast Asian Nations and five Asia-Pacific countries (ASEAN Plus Five), Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation (BIMSTEC), European Union (EU), India-Japan-Australia trilateral framework, and Southern African Customs Union (SACU). It also tries to look at how they can create new opportunities for trade among the member countries. The authors sort out which of the above-recorded arrangements will be the most welfare upgrading for India. The chapter attempts to comprehend whether India ought to pull out for the occasions to be essential for value-chains in the areas. Maximum gains occur when India liberalizes with all, that is, liberalizes multilaterally followed by ASEAN 10, RCEP, Indo Pacific, CPTPP, MENA, EU 27, 54 nations African FTA, GCC, among others. Services and investment liberalization would bring further dividends to India.
Greenfield FDI Determinants in the MENA Region
Authors: Ben Romdhane Loukil Youssra , Kammoun Souhaila , Ouerghi Imen
Published: May 2021

The purpose of the chapter is twofold. Firstly, the authors intend to identify the main determinants of Greenfield FDI in a context of political and economic changes by choosing inflation, trade freedom, and investment freedom as macroeconomic variables and political instability as an institutional variable. Secondly, they determine which environmental sector may affect this mode of foreign investment in MENA region. Using dynamic panel models on a sample of 13 countries over the period 2010-2018, they perform econometric modeling to measure the relationship between Greenfield FDI, macroeconomic aggregates, and the relationship between FDI and the environmental sector. They find that trade openness stimulates foreign investment in MENA region and that the lack of inflation control may disrupt the inflow of Greenfield FDI since it reflects the economic stability of the host countries. Furthermore, there is a positive relationship between Greenfield FDI and environmental sectors. The chapter suggests some relevant practical implications to improve the attractiveness of Greenfield FDI in the MENA region.
Towards a Utility Theory of Privacy and Information Sharing and the Introduction of Hyper-Hyperbolic Discounting in the Digital Big Data Age
Authors: Puaschunder Julia
Published: May 2021

Today enormous data storage capacities and computational power in the e-big data era have created unforeseen opportunities for big data hoarding corporations to reap hidden benefits from individuals' information sharing, which occurs bit by bit in small tranches over time. Behavioral economics describes human decision-making fallibility over time but has—to this day—not covered the problem of individuals' decision to share information about themselves in tranches on social media and big data administrators being able to reap a benefit from putting data together over time and reflecting the individual's information in relation to big data of others. The decision-making fallibility inherent in individuals having problems understanding the impact of their current information sharing in the future is introduced as hyper-hyperbolic discounting decision-making predicament.
An Effective and Computationally Efficient Approach for Anonymizing Large-Scale Physical Activity Data
Authors: Parameshwarappa Pooja , Chen Zhiyuan , Koru Gunes
Published: May 2021

Publishing physical activity data can facilitate reproducible health-care research in several areas such as population health management, behavioral health research, and management of chronic health problems. However, publishing such data also brings high privacy risks related to re-identification which makes anonymization necessary. One of the challenges in anonymizing physical activity data collected periodically is its sequential nature. The existing anonymization techniques work sufficiently for cross-sectional data but have high computational costs when applied directly to sequential data. This article presents an effective anonymization approach, multi-level clustering-based anonymization to anonymize physical activity data. Compared with the conventional methods, the proposed approach improves time complexity by reducing the clustering time drastically. While doing so, it preserves the utility as much as the conventional approaches.
Security- and Privacy-Aware Computing in Cloud With User Mobility
Authors: Sen Sayani , Roy Sathi , Biswas Suparna , Chowdhury Chandreyee
Published: May 2021

Today's computational model has been undergoing a huge paradigm shift from personalized, local processing using local processing unit (LPU) to remote processing at cloud servers located globally. Advances in sensor-based smart applications such as smart home, smart health, smart transport, smart environment monitoring, etc. are generating huge data which needs to stored, pre-processed, analyzed using machine learning and deep learning techniques, which are resource-hungry, to generate results to be saved for future reference, and all these need to be done in real time, with scalability support satisfying user data privacy and security that may vary from application to application. In smart application like remote health monitoring and support, patient data needs utmost privacy besides confidentiality, integrity, and availability.
A Compliance-Driven Framework for Privacy and Security in Highly Regulated Socio-Technical Environments
Authors: Saidane Ayda , Al-Sharieh Saleh
Published: May 2021

Regulatory compliance is a top priority for organizations in highly regulated ecosystems. As most operations are automated, the compliance efforts focus on the information systems supporting the business processes of the organizations and, to a lesser extent, on the humans using, managing, and maintaining them. Yet, the human factor is an unpredictable and challenging component of a secure system development and should be considered throughout the development process as both a legitimate user and a threat. In this chapter, the authors propose COMPARCH as a compliance-driven system engineering framework for privacy and security in socio-technical systems. It consists of (1) a risk-based requirement management process, (2) a test-driven security and privacy modeling framework, and (3) a simulation-based validation approach. The satisfaction of the regulatory requirements is evaluated through the simulation traces analysis. The authors use as a running example an E-CITY system providing municipality services to local communities.
Semantically Secure Classifiers for Privacy Preserving Data Mining
Authors: Sumana M.  , Hareesha K. S.  , Kumar Sampath
Published: May 2021

Essential predictions are to be made by the parties distributed at multiple locations. However, in the process of building a model, perceptive data is not to be revealed. Maintaining the privacy of such data is a foremost concern. Earlier approaches developed for classification and prediction are proven not to be secure enough and the performance is affected. This chapter focuses on the secure construction of commonly used classifiers. The computations performed during model building are proved to be semantically secure. The homomorphism and probabilistic property of Paillier is used to perform secure product, mean, and variance calculations. The secure computations are performed without any intermediate data or the sensitive data at multiple sites being revealed. It is observed that the accuracy of the classifiers modeled is almost equivalent to the non-privacy preserving classifiers. Secure protocols require reduced computation time and communication cost. It is also proved that proposed privacy preserving classifiers perform significantly better than the base classifiers.
Preserving Data Privacy in Electronic Health Records Using Blockchain Technology
Authors: Sathiyabhama B.  , Rajeswari K. C.  , Reenadevi R.  , Arul Murugan R.
Published: May 2021

Technology is a boon to mankind in this fast-growing era. The advancement in technology is the predominant factor for the sophisticated way of living of the people. In spite of technology, revolution happens across the world, and mankind still suffers due to various health issues. Healthcare industries take immense measures to improve the quality of life. An enormous volume of digital data is being handled every day in the healthcare industry. There arises a need for the intervention of technology in the healthcare industry to be taken to a greater extent. The prime duty of any healthcare industry is to store and maintain those data in the form of electronic health records (EHR) in a secured manner.
Big Data, Privacy, and Healthcare
Authors: Bhatt Nirav , Thakkar Amit
Published: May 2021

In the era of big data, large amounts of data are generated from different areas like education, business, stock market, healthcare, etc. Most of the available data from these areas are unstructured, which is large and complex. As healthcare industries become value-based from volume-based, there is a need to have specialized tools and methods to handle it. The traditional methods for data storage and retrieval can be used when data is structured in nature. Big data analytics provide technologies to store large amounts of complex healthcare data. It is believed that there is an enormous opportunity to improve lives by applying big data in the healthcare industry. No industry counts more than healthcare as it is a matter of life and death. Due to rapid development of big data tools and technologies, it is possible to improve disease diagnosis more efficiently than ever before, but security and privacy are two major issues when dealing with big data in the healthcare industry.
Security Issues and Challenges Related to Big Data
Authors: Undavia Jaimin N. , Patel Atul , Patel Sheenal
Published: May 2021

Availability of huge amount of data has opened up a new area and challenge to analyze these data. Analysis of these data become essential for each organization and these analyses may yield some useful information for their future prospectus. To store, manage and analyze such huge amount of data traditional database systems are not adequate and not capable also, so new data term is introduced – “Big Data”. This term refers to huge amount of data which are used for analytical purpose and future prediction or forecasting. Big Data may consist of combination of structured, semi structured or unstructured data and managing such data is a big challenge in current time. Such heterogeneous data is required to maintained in very secured and specific way. In this chapter, we have tried to identify such challenges and issues and also tried to resolve it with specific tools.
Data Breach on Consumer Behavior
Authors: Chen Ruimin
Published: May 2021

Big data is now affecting the daily lives in many different areas, such as payment system, online shopping, health services and so forth. There has no doubt that big data is able to make the lives of people more convenient to a certain extent, but it can also threaten privacy security in the meantime. In order to explore the hazardous effects of data breach on consumer behavior and understand how netizens act and feel when experiencing it, a questionnaire was completed by 110 participants. This article will demonstrate the primary issues on potential security risks on big data, especially the effects of data breach on consumer behavior by discussing the causes, solutions and ethical concerns.
Promoting Cybersecurity Compliance
Authors: Harris Mark A. , Martin Ronald
Published: May 2021

In a global online economy, organizations are tasked with protecting their cybersecurity assets. Penalties from failing to protect assets, such as customer data, can severely harm an organization and even lead to bankruptcy. Cybersecurity governance programs need to be aware of the laws and regulations affecting their organizations and use applicable standards or frameworks to develop appropriate cybersecurity polices and controls. Compliance programs then need to monitor policy compliance on a continuing basis. This chapter discusses the laws, regulations, and standards that are used to create cybersecurity polices and the typical tools used to measure compliance. In addition, theoretical cybersecurity compliance research is reviewed to highlight supplementary techniques to improve compliance.
Factors Influencing Online Purchase Intention in Qatar
Authors: Alkailani Lubna , Abu-Shanab Emad Ahmed
Published: May 2021

This study investigated the factors influencing consumers' purchase intention from online stores in Qatar. Moreover, it tried to verify if payment method moderates the relationships concerning the suggested factors and online purchase intention. This research extended the theory of reasoned behavior (TRA) with trust as a predictor and payment method as a moderator. A total of 283 valid responses were collected from Qatari residents through an online questionnaire and analyzed the data to test the research hypotheses. The findings of this research indicated that all proposed factors significantly influenced online purchase intention. Results also indicated that there is no moderation effect of payment method on the proposed hypotheses. Further investigations revealed that all proposed factors significantly affect the online purchase intention for customers who prefer to use credit card payment. Managerial implications and recommendations were presented in addition to the study limitations and suggestions for future research.
The Politics of Climate Change and the Rising Demand for Global Energy in the 21st Century
Authors: Wogu Ikedinachi Ayodele Power , Njie Sharon Nanyongo , Ezennwa Emmanuel Onyekachi , Chukwuedo Charles Natahniel , Ukagba George U. , Misra Sanjay , Uniamikogbo Emmanuel , Olu-Owolabi Esther Fadeke
Published: May 2021

Established that most governments prefer to boost global energy supply because it improves economies and translates to gainful employment for citizens, the rising global demand for energy from various sectors continues to trigger unprecedented consequences on the environment, resulting in hazardous implications. Hence, scientists argue that the rising demand for global energy by industrialized nations increases the vulnerability of persons and polities where these energy and mineral resources abound. Consequently, governments, multinationals, etc. are at a crossroads regarding how best to address this dilemma. Creswell's mix-method research deign and Merlyn's ex-post facto research methods for analyzing qualitative and quantitative data previously obtained from similar studies were used for attaining the objectives of the research. The study identified troubling and high-level politicking at play in most affected countries. Recommendations geared towards addressing the dilemmas emanating from the rising global demand for energy by governments and scholars were proffered.
Optimizing Layout of Distributed Generation Sources of Power Supply System of Agricultural Object
Authors: Daus Yuliia , Kharchenko Valeriy , Yudaev Igor
Published: May 2021

The increasing penetration of photovoltaic technology calls for the development of an effective method for optimization of grid-connected photovoltaic power plants. Although extensive studies on the definition, implementation, and optimization of these systems have been conducted, the design and management of a smart energy system remains a critical challenge. The purpose of the work is to increase efficiency of power supply system of agricultural facility by optimizing the placement and selection of parameters of photovoltaic sources of distributed generation. Application of photovoltaic sources of distributed generation as part of power supply system of agricultural enterprise allows to reduce the total consumption from the network in average basing on solar intensity data for 22 years by 40-53% from April to October, which is most expedient in view of the fact that this is a period of intensive work of the enterprise and the greatest load on its consumers; by 24-30% in February, March, and October; and by 14-17% the rest of the time.
Effect of Influencer Marketing on Online Impulse Purchase
Authors: Trivedi Jay P.
Published: May 2021

Fashion retailers are increasingly using influencer marketing to build a consumer-brand relationship. However, influencer marketing remains an understudied area, and choosing from among traditional attractive celebrity influencers and expert influencers remains a conundrum for marketers. Hence, this research examines the comparative effectiveness of an attractive celebrity influencer, vis-à-vis an expert influencer on online consumer-brand engagement, further resulting in an online impulse purchase. The moderating role of impulse buying tendency between online consumer-brand engagement and online impulse purchase is also examined. Using survey data from respondents following fashion influencers, the author tested the proposed hypotheses using structural equation modeling. The findings indicate that attractive celebrity influencers exhibit a significant effect on online consumer-brand engagement, which further leads to online impulse purchase. The findings also establish the moderating effect of impulse buying tendency and the mediating role of online consumer-brand engagement.
Dynamic Measurement and Evaluation of Hotel Customer Satisfaction Through Sentiment Analysis on Online Reviews
Authors: Gang Zhou , Chenglin Liao
Published: May 2021

Both researchers and practitioners have attached great importance to the measurement and evaluation of hotel customer satisfaction. However, there are several problems in the dimensions, methods and conclusions. Thus, it is urgent to standardize the theories, methods, and techniques. The purpose of this study is to propose a dynamic measurement and evaluation framework for hotel customer satisfaction through sentiment analysis on online reviews. The framework consists of five steps: (1)The corpus is obtained from online review sites; (2)From the perspective of managers, the useful texts are recognized; (3)Based on the useful texts, a three-layer index system is created; (4)The center term-based short sentence sentimental orientation (CTSSSO) algorithm is developed to compute emotional intensity, then dynamically measure the customer satisfaction; (5)The dynamic important performance competitor analysis (DIPCA) is adopted for dynamic evaluation of customer satisfaction.The feasibility of our framework was demonstrated through a case study on the online reviews of two five-star hotels.
Manufacturing and Characterization of Functionally Graded Material Automotive Piston Using Centrifugal Casting Technique
Authors: Elkotb Hazem H. , Mostafa Rania , Abdel Samad A. A. , Enab Tawakol A.
Published: May 2021

The process of fabricating reliable materials according to efficient usage has become one of the most vital concerns. In this paper, the fabrication of functionally graded materials (FGMs) is the target using a specified application of an internal combustion engine piston model to achieve such a gradient. With a convenient rotational speed under the concept of centrifugal casting technique, the required gradient piston was successfully produced from two pure aluminum alloys A336 and A242 by such a new mechanical technique for having the required gradient. The percentages of internal ingredients, mainly, silicon were controlled axially through the piston. Chemical composition analysis, micro-hardness and wear resistance tests were performed to check the gradient and to know the difference between mechanical properties for each piston portion from its top combustion chamber to its skirt, achieving compatible results through performed tests. Obvious opposite direction gradient of silicon content to copper content appeared. Micro-hardness, wear resistance and coefficient of friction values showed a successfully gradient in the axial direction of the piston model.
Recycling of Polyethylene Terephthalate Wastes in Production of Hollow Sandcrete Blocks for Sustainable Construction
Authors: Olofinnade Oluwarotimi Michael , Davies Iyinoluwa E.E. , Egwuonwu Ifeoma W.
Published: May 2021

This study investigates the suitability of crushed polyethylene terephthalate (PET) waste, which is a non-biodegradable generated waste as a substitute material for natural sand in the production of hollow sandcrete blocks for sustainable infrastructure. The physical properties of the natural sand and crushed PET aggregate materials used in the batching mixtures which include; specific gravity, water absorption, bulk density and particle size distribution were determined. While the mechanical properties; density, compressive strength, and the water absorption of the produced hollow sandcrete block samples using the granulated PET aggregate as a replacement for natural sand at 5%, 10%, 30% and 50% were studied. Results showed that the PET aggregates exhibit lower physical properties compare to natural sand. The addition of the finely granulated PET aggregates as a partial substitute for natural sand gradually reduced the density of the hollow sandcrete blocks as the replacement increases in the mix. However, the water absorption tendency of the sandcrete blocks reduces as the percentage dosages of PET aggregate increases. A similar reduction trend was noticed in the compressive strength of the produced hollow sandcrete blocks. The results showed a strength reduction from 2.564 N/mm2 to 1.140 N/mm2 for sandcrete mixes containing 5% and 50% PET, respectively, and 2.991 N/mm2 to 1.510 N/mm2 for sandcrete mixes containing 5% and 50% PET, respectively as the percentage substitution of sand with PET increases for 7 and 28 days curing age. The obtained results indicate the possibility of using granulated PET aggregate at 5% sand replacement in production of hollow sandcrete blocks of comparable strength to conventional sandcrete blocks. This will help to promote green production for sustainable infrastructure and reducing the menace of plastic pollution in line with the UN Sustainable Development Goals.
A Posttranscriptional Pathway of CD40 Ligand mRNA Stability Is Required for the Development of an Optimal Humoral Immune Response
Authors: Narayanan Bitha , Prado de Maio Diego , La Porta James , Voskoboynik Yekaterina , Ganapathi Usha , Xie Ping , Covey Lori R.
Published: May 2021

CD40 ligand (CD40L) mRNA stability is dependent on an activation-induced pathway that is mediated by the binding complexes containing the multifunctional RNA-binding protein, polypyrimidine tract-binding protein 1 (PTBP1) to a 3′ untranslated region of the transcript. To understand the relationship between regulated CD40L and the requirement for variegated expression during a T-dependent response, we engineered a mouse lacking the CD40L stability element (CD40LΔ5) and asked how this mutation altered multiple aspects of the humoral immunity. We found that CD40LΔ5 mice expressed CD40L at 60% wildtype levels, and lowered expression corresponded to significantly decreased levels of T-dependent Abs, loss of germinal center (GC) B cells and a disorganized GC structure. Gene expression analysis of B cells from CD40LΔ5 mice revealed that genes associated with cell cycle and DNA replication were significantly downregulated and genes linked to apoptosis upregulated. Importantly, somatic hypermutation was relatively unaffected although the number of cells expressing high-affinity Abs was greatly reduced. Additionally, a significant loss of plasmablasts and early memory B cell precursors as a percentage of total GL7+ B cells was observed, indicating that differentiation cues leading to the development of post-GC subsets was highly dependent on a threshold level of CD40L. Thus, regulated mRNA stability plays an integral role in the optimization of humoral immunity by allowing for a dynamic level of CD40L expression on CD4 T cells that results in the proliferation and differentiation of pre-GC and GC B cells into functional subsets.
An Antigen Capture Assay for the Detection of Mycolactone, the Polyketide Toxin of Mycobacterium ulcerans
Authors: Warryn Louisa , Dangy Jean-Pierre , Gersbach Philipp , Gehringer Matthias , Altmann Karl-Heinz , Pluschke Gerd
Published: May 2021

Mycolactone is a cytotoxin responsible for most of the chronic necrotizing pathology of Mycobacterium ulcerans disease (Buruli ulcer). The polyketide toxin consists of a 12-membered lactone ring with a lower O-linked polyunsaturated acyl side chain and an upper C-linked side chain. Mycolactone is unique to M. ulcerans and an immunological Ag capture assay would represent an important tool for the study of Buruli ulcer pathogenesis and for laboratory diagnosis. When testing sets of mycolactone-specific mouse mAbs, we found that Abs against the hydrophobic lower side chain only bind mycolactone immobilized on a solid support but not when present in solution. This observation supports previous findings that mycolactone forms micellar structures in aqueous solution with the hydrophobic region sequestered into the inner core of the aggregates. Although an Ag capture assay typically requires two Abs that recognize nonoverlapping epitopes, our search for matching pairs of mAbs showed that the same mAb could be used both as capture and as detecting reagent for the detection of the mycolactone aggregates. However, the combination of a core-specific and a core/upper side chain–specific mAb constituted the most sensitive ELISA with a sensitivity in the low nanogram range. The results of a pilot experiment showed that the sensitivity of the assay is sufficient to detect mycolactone in swab samples from Buruli ulcer lesions. Although the described capture ELISA can serve as a tool for research on the biology of mycolactone, the assay system will have to be adapted for use as a diagnostic tool.
Selective Activation of MST1/2 Kinases by Retinoid Agonist Adapalene Abrogates AURKA-Regulated Septic Arthritis
Authors: Yadav Preeti , Bhatt Bharat , Balaji Kithiganahalli Narayanaswamy
Published: May 2021

Septic arthritis is a chronic inflammatory disorder caused by Staphylococcus aureus invasion of host synovium, which often progresses to impairment of joint functions. Although it is known that disease progression is intricately dependent on dysregulated inflammation of the knee joint, identification of molecular events mediating such imbalance during S. aureus–induced septic arthritis still requires detailed investigation. In this article, we report that Aurora kinase A (AURKA) responsive WNT signaling activates S. aureus infection–triggered septic arthritis, which results in inflammation of the synovium. In this context, treatment with adapalene, a synthetic retinoid derivative, in a mouse model for septic arthritis shows significant reduction of proinflammatory mediators with a simultaneous decrease in bacterial burden and prevents cartilage loss. Mechanistically, adapalene treatment inhibits WNT signaling with concomitant activation of HIPPO signaling, generating alternatively activated macrophages. Collectively, we establish adapalene as a promising strategy to suppress S. aureus–induced irreversible joint damage.
RALDH Activity Induced by Bacterial/Fungal Pathogens in CD16+ Monocyte-Derived Dendritic Cells Boosts HIV Infection and Outgrowth in CD4+ T Cells
Authors: Cattin Amélie , Wacleche Vanessa Sue , Fonseca Do Rosario Natalia , Marchand Laurence Raymond , Dias Jonathan , Gosselin Annie , Cohen Eric A. , Estaquier Jérôme , Chomont Nicolas , Routy Jean-Pierre , Ancuta Petronela
Published: May 2021

HIV reservoirs persist in gut-homing CD4+ T cells of people living with HIV and receiving antiretroviral therapy, but the antigenic specificity of such reservoirs remains poorly documented. The imprinting for gut homing is mediated by retinoic acid (RA), a vitamin A–derived metabolite produced by dendritic cells (DCs) exhibiting RA-synthesizing (RALDH) activity. RALDH activity in DCs can be induced by TLR2 ligands, such as bacterial peptidoglycans and fungal zymosan. Thus, we hypothesized that bacterial/fungal pathogens triggering RALDH activity in DCs fuel HIV reservoir establishment/outgrowth in pathogen-reactive CD4+ T cells. Our results demonstrate that DCs derived from intermediate/nonclassical CD16+ compared with classical CD16− monocytes exhibited superior RALDH activity and higher capacity to transmit HIV infection to autologous Staphylococcus aureus–reactive T cells. Exposure of total monocyte-derived DCs (MDDCs) to S. aureus lysates as well as TLR2 (zymosan and heat-killed preparation of Listeria monocytogenes) and TLR4 (LPS) agonists but not CMV lysates resulted in a robust upregulation of RALDH activity. MDDCs loaded with S. aureus or zymosan induced the proliferation of T cells with a CCR5+integrin β7+CCR6+ phenotype and efficiently transmitted HIV infection to these T cells via RALDH/RA–dependent mechanisms. Finally, S. aureus– and zymosan-reactive CD4+ T cells of antiretroviral therapy-treated people living with HIV carried replication-competent integrated HIV-DNA, as demonstrated by an MDDC-based viral outgrowth assay. Together, these results support a model in which bacterial/fungal pathogens in the gut promote RALDH activity in MDDCs, especially in CD16+ MDDCs, and subsequently imprint CD4+ T cells with gut-homing potential and HIV permissiveness. Thus, nonviral pathogens play key roles in fueling HIV reservoir establishment/outgrowth via RALDH/RA–dependent mechanisms that may be therapeutically targeted.
The Impact of Mineralocorticoid Receptor Antagonist Use on All-cause Mortality in Acute Heart Failure Patients
Authors: Al-Zakwani Ibrahim , Al-Jarallah Mohammed , Rajan Rajesh , Sulaiman Kadhim , Dashti Raja , Bulbanat Bassam , Alsheikh-Ali Alawi A , Panduranga Prashanth , AlHabib Khalid F. , Suwaidi Jassim Al , Al-Mahmeed Wael , AlFaleh Hussam , Elasfar Abdelfatah , Al-Motarreb Ahmed , Ridha Mustafa , Bazargani Nooshin , Asaad Nidal , Amin Haitham , Salam Amar M.
Published: May 2021

Background:

The impact of mineralocorticoid receptor antagonist (MRA) use in acute heart failure (AHF) patients in the Middle East is not well studied. The objective of this study was to examine the impact of MRA therapy on all-cause mortality in AHF patients in the Middle East stratified by left ventricular ejection fraction.

Methods:

Data were analyzed from 3792 consecutive patients admitted to 47 hospitals in 7 Middle Eastern countries.

Results:

The overall mean age was 59 ± 15 years and 62% (n = 2353) were male. At discharge, MRA therapy was prescribed in 34% (n = 1301) of the patients. A total of 54% (n = 2048) of the patients had AHF with reduced ejection fraction (EF) (HFrEF) (<40%), 23% (n = 880) had HF with mid-range EF (HFmrEF) (40%–49%), and 23% (n = 864) had HF with preserved EF (HFpEF) (≥50%). MRA therapy was associated with lower cumulative all-cause 3-month mortality in those with HFrEF (adjusted odds ratio [aOR], 0.55; 95% [confidence interval (CI): 0.37–0.80: P = 0.002), those with HFmrEF (aOR, 0.43; 95% CI: 0.19–0.99: P = 0.047), and in those with HFpEF (aOR, 0.45; 95% CI: 0.22–0.92: P = 0.029) when compared to those that were not on MRA therapy. MRA therapy was also associated with lower cumulative all-cause 12-month mortality in those with HFrEF (aOR, 0.65; 95% CI: 0.49–0.86: P = 0.002) and in those with HFmrEF (0.52; 95% CI: 0.29–0.91: P = 0.021).

Conclusion:

MRA therapy was associated with lower all-cause mortality at 3 months and at 12 months in AHF patients with reduced and mid-range EF in the Middle East.
Midline Solitary Osteochondroma of C2 Vertebra with Myelopathy in a Child
Authors: Basu Saumyajit , Agarwal Naveen , Gowda Somashekar Doddabhadre , Bhanta Aditya
Published: May 2021

Spinal osteochondromas with neurological deficits are rare. Only 0.5% to 1% of spinal osteochondromas present with neurological dysfunction. We hereby present a case of osteochondroma of the C2 lamina with neurological deficit and unique presentation. A 10-year-old female presented with a history of severe weakness of all four limbs after a fall. Weakness had spontaneously improved over initial three days and she presented to us with mild weakness of the right upper limb about two weeks after the fall. On examination, neck movements were full and painless with spastic quadriparesis and a motor power of grade 4/5 in all four limbs with extensor plantars. On radiology, CT scan of the cervical spine showed an osseous outgrowth from the C2 lamina in the midline projecting into the spinal canal, directed superiorly toward the dens. An MRI showed spinal-cord compression with cord deformation and signal changes. She underwent en bloc excision of the tumor mass, which was severely impinging on the spinal cord. Histopathology confirmed a diagnosis of osteochondroma. At four-year follow-up, there was complete recovery with no signs of recurrence. Spinal osteochondroma is a rare but potential cause of spinal-cord compression in a child with varied presentation.
Concurrent laparoscopic totally extraperitoneal inguinal hernia repair and transurethral resection of prostate
Authors: Harvitkar Rafique Umer , Shetty Prakash Chandra , Joshi Abhijit
Published: May 2021

Aim:

This study aimed to evaluate concurrent laparoscopic totally extraperitoneal (TEP) inguinal hernia repair and transurethral resection of the prostate (TURP) with determination of outcomes.

Materials and Methods:

This retrospective study was conducted at our hospital, from June 2011 to June 2020. Over 9 years, 17 patients with co-existing uncomplicated unilateral or bilateral inguinal hernia (primary/recurrent) and significant benign prostatic hypertrophy were operated in the same sitting. The following outcomes were compared: duration of the surgery, conversion to open hernia surgery, intraoperative and post-operative complications, duration of hospital stay, recurrence, time taken to resume normal activity and cost of the treatment.

Results:

This study included 17 patients with a mean age of 65 years (range of 50–87 years). The average time taken for the surgery was 115 min with no conversion to open hernia repair. The mean post-operative stay was 3.7 days. There were four patients (23.5%) with seromas identified at day 10, only two remained at 6 weeks and none at 12 weeks. None had significant bleeding intraoperatively or postoperatively. There was no superficial or deep wound infection (including mesh infection). There was no recurrence of inguinal hernia. Two patients (11.7%) developed post-TURP urethral stricture and underwent cystoscopic stricturoplasty, 3 and 2.5 months after the initial procedure.

Conclusion:

Concurrent TEP inguinal hernia repair and TURP is a practical, safe and cost-effective procedure.
Effects of Auditory and Visual Interference Control on Visuospatial Working Memory in Children with ADHD
Authors: Wangkawan Thitiya , Lai Cynthia , Munkhetvit Peeraya , Yung Trevor , Chinchai Supaporn
Published: May 2021

Background:

Interference control is the cognitive control needed to prevent interference due to competition of relevant and irrelevant information that closely related to working memory. The aim of this study was to examine the effects of auditory and visual interference control on visuospatial working memory of children with ADHD.

Methods:

The participants included thirty children with ADHD and thirty normal control children aged 7–12 years old. All children took the computerized test of visuospatial working memory assessment. The test comprised the N-back and running Memory tasks divided into three conditions: noninterference, auditory interference, and visual interference in three levels of difficulty.

Results:

The results revealed that there was a significant difference in N-back with auditory interference (t = 2.13, P = 0.04) and N-back with visual interference task (t = 2.48, P = 0.02) between normal control children and children with ADHD. However, there was no significant difference in N-back with noninterference task (t = 1.61, P = 0.11) between normal control children and children with ADHD. There was a significant difference in running memory with noninterference (t = 5.34, P ≤ 0.001), running memory with auditory interference (t = 6.23, P ≤ 0.001), and running memory with visual interference task (t = 5.86, P ≤ 0.001) between normal control children and children with ADHD. In addition, the comparison of the mean score revealed that children with ADHD had poorer performance of interference control on visuospatial working memory tasks than normal control children in overall tasks.

Conclusion:

Children with ADHD exhibited inefficient control over themselves, especially in the interference condition tasks in which they performed more error responses when interacting in the tasks. The present study supports the evidence-based mechanisms of auditory and visual interference control in visuospatial working memory of children with ADHD.
Thoracic Intradural Extramedullary Lipomas
Authors: Hsiang-Chih Liao , Hueng Dueng-Yuan , Chen Yuan-Hao , Ma Hsin-I , Ju Da-Tong , Chi-Tun Tang
Published: May 2021

Intradural extramedullary lipomas are rare congenital and histologically benign tumors that represent <1% of all spinal cord tumors. However, the indications for surgery and the degree of resection or decompression are under debate. We report on our experience with spinal decompression for the treatment of one intradural extramedullary thoracic lipomas.
Epidemiological distribution of primary central nervous system tumors in the Western Province of Saudi Arabia: a local registry from neuroscience-affiliated centers
Authors: Kurdi Maher , Butt Nadeem Shafique , Baeesa Saleh , Alghamdi Badrah , Maghrabi Yazid , Bardeesi Anas , Saeedi Rothaina , Lary Ahmed I.
Published: May 2021

OBJECTIVES: Central nervous system (CNS) tumors are a major and growing global healthcare challenge. Western Saudi Arabia has an inconsistent data registry; therefore, the epidemiology of CNS tumors is unclear across the country. This study is aimed to assemble the epidemiological matrix of CNS tumors in the Western Province of Saudi Arabia.METHODS: A retrospective analysis was performed using clinical data obtained from 3 neuroscience centers in Western Saudi Arabia in the period 2014-2019. The sample size included 663 adult and pediatric cases from the local and expatriate populations diagnosed with CNS tumors. The distributions of age, sex, clinical presentation, tumor location, type of surgery, histological subtype, genetic characteristics, and recurrence rate were explored.RESULTS: The analysis included 500 adult cases and 163 pediatric cases up to 18 years of age with a male-to-female ratio of 1.16. The mean age at diagnosis was 38.0±22.6 years. The supratentorium was the most common location (n=515, 77.7%). Most patients presented with headache (n=298, 44.9%), followed by a focal neurological deficit (19.9%). The most common primary CNS tumor was glioblastoma (n=234, 35.3%), followed by meningioma (n=100, 15.1%). The recurrence rate after surgery was estimated to be 40.9% among all CNS tumors.CONCLUSIONS: This is the first tumor registry of Western Province of Saudi Arabia that describes the distribution of primary CNS tumors and highlights their epidemiological matrix. Several incidence trends in terms of histological type, age group, sex, location, and recurrence were determined, and some genetic characteristics were recognized.
Равномерное приближение функций решениями однородных сильно эллиптических уравнений второго порядка на компактах в $\mathbb{R}^2$
Authors: Mazalov Maksim Yakovlevich
Published: May 2021

Получен критерий равномерной приближаемости функций решениями однородных сильно эллиптических уравнений второго порядка с постоянными комплексными коэффициентами на компактах в $\mathbb{R}^2$ (частный случай гармонических приближений не выделяется).
Критерий формулируется в терминах единственной (скалярной) емкости Харви и Полкинга, связанной со старшим коэффициентом разложения в ряд типа Лорана (для хорошо изученного случая не сильно эллиптических уравнений соответствующая емкость тривиальна).
В доказательстве применяются усовершенствованная схема Витушкина, специальные геометрические конструкции и методы теории сингулярных интегралов. Рассматриваемая задача, в силу неоднородности фундаментальных решений сильно эллиптических операторов в $\mathbb{R}^2$, технически сложнее аналогичной задачи в $\mathbb{R}^d$, $d>2$.
Библиография: 19 наименований.
Критерии $C^1$-приближаемости функций решениями однородных эллиптических уравнений второго порядка на компактах в $\mathbb{R}^N$, $N \geqslant 3$
Authors: Paramonov Petr Vladimirovich
Published: May 2021

В работе получены емкостные критерии индивидуальной приближаемости функций решениями однородных эллиптических уравнений второго порядка с постоянными комплексными коэффициентами в норме пространства $C^1$ типа Уитни на компактах в $\mathbb{R}^N$, $N \geqslant 3$. Случай $N=2$ изучен ранее в недавней работе автора и К. Толсы. Для $C^1$-аппроксимаций гармоническими функциями (при всех $N$) автором ранее были найдены критерии в более слабой формулировке. Установлен ряд метрических свойств рассматриваемых емкостей.
Библиография: 25 наименований.
Факторизация Неванлинны в весовых классах аналитических функций переменной гладкости
Authors: Shirokov Nikolai Alekseevich
Published: May 2021

В работе определен новый класс аналитических в единичном круге и непрерывных в замкнутом круге функций переменной гладкости. Для функций из нового класса построена теория внешне-внутренней факторизации Неванлинны, учитывающая влияние внутреннего сомножителя на внешнюю функцию.
Библиография: 19 наименований.