Proximity Communication Research Articles

Radiographic complicated and uncomplicated descending aortic dissections: aortic morphological differences by CT angiography and risk factor analysis.

To identify radiographic differences between patients with uncomplicated and complicated descending aortic dissections. Between April 2009 and July 2021, 209 patients with acute descending aortic dissections were analysed as complicated (malperfusion, rupture, diameter progress, and diameter ≥ 55 mm) or uncomplicated. Detailed CTA measurements (slice thickness ≤ 3 mm) were taken in multiplanar reconstruction. A composite endpoint (early aortic failure) was defined as reoperation, diameter progression, and early mortality. Seventy-seven patients were female (36.8%) [complicated n = 27 (36.5%); uncomplicated n = 50 (37.0%) P = 1.00]. Seventy-four (35%) patients were categorized as morphologically complicated, and 135 (65%) as uncomplicated. In patients with complicated dissections, the dissection extended more frequently to the aortic bifurcation (P = 0.044), the coeliac trunk (P = 0.003), the superior mesenteric artery (P = 0.007), and both iliac arteries (P < 0.001) originated less frequently from the true lumen. The length of the most proximal communication (entry) in type B aortic dissection was longer, 14.0 mm [12.0 mm; 27.0 mm] vs. 6.0 mm [4,0 mm; 13.0 mm] in complicated cases (P = 0.005). Identified risk factors for adverse aortic events were connective tissue disease [HR 8.0 (1.9-33.7 95% CI HR)], length of the aortic arch [HR 4.7 (1.5-15.1 95% CI HR)], a false lumen diameter > 19.38 mm [HR 3.389 (1.1-10.2 95% CI HR)], and origin of the inferior mesenteric artery from the false lumen [HR 4.2 (1.0-5.5 95% CI HR)]. We identified significant morphological differences and predictors for adverse events in patients presenting complicated and uncomplicated descending dissections. Our morphological findings will help guide future aortic therapies, taking a tailored patient approach.

Illuminating the impact of the proximity communication modes between redox metallic and acidic zeolite sites during hydro-conversion of n-heptane

The unique physicochemical properties of “redox-acid” bifunctional zeolites make them an essential tool in the petrochemical industry, especially in the hydro-conversion of linear alkanes to deliver high-octane fuels. The current research activities in this domain are primarily tailored towards evaluating the “intimacy/proximity” criteria among two catalytically active sites and minimizing the loading of noble metals (e.g., Pd or Pt) in catalysis. However, the chemistry behind the communication mode (i.e., “through-space” or “through-bond” interaction between metallic and acid sites) has remained vastly underexplored during the hydro-conversion of n-alkanes over Pt or Pd/zeolites. To dig deeper into this uncharted territory, this work demonstrates that both “through-space” (cf. metals in extra-framework position in/on zeolite) and “through-bond” (cf. metals on the zeolite framework) bifunctionality favors the hydroisomerization step, while the later partially also promote the hydro-cracking. Their working protocol was probed by the diverse material characterization techniques that improved the understanding of the zeolite-catalyzed hydrocarbon conversion processes.

Formation Control Over Delaunay Triangulation Networks With Guaranteed Collision Avoidance

This article addresses the collision avoidance of networked swarms of mobile agents. A gradient-based control scheme with artificial potential fields guides all the agents into a distance-based formation. While, in the relevant literature, unbounded forces are used to achieve collision avoidance, this article shows a way to guarantee collision avoidance that respects control input limitations. To this end, it is proposed to use Morse potential functions, and it is shown how to parameterize them appropriately. The results are extended to the case that a switching proximity communication network in form of a Delaunay triangulation is applied to the networked system. It is shown that under which conditions the collision avoidance is preserved among the overall network. The proposed method is evaluated experimentally with mobile robots.

Buried RF Sensors for Smart Road Infrastructure: Empirical Communication Range Testing, Propagation by Line of Sight, Diffraction and Reflection Model and Technology Comparison for 868 MHz-2.4 GHz.

Updating the road infrastructure requires the potential mass adoption of the road studs currently used in car detection, speed monitoring, and path marking. Road studs commonly include RF transceivers connecting the buried sensors to an offsite base station for centralized data management. Since traffic monitoring experiments through buried sensors are resource expensive and difficult, the literature detailing it is insufficient and inaccessible due to various strategic reasons. Moreover, as the main RF frequencies adopted for stud communication are either 868/915 MHz or 2.4 GHz, the radio coverage differs, and it is not readily predictable due to the low-power communication in the near proximity of the ground. This work delivers a reference study on low-power RF communication ranging for the two above frequencies up to 60 m. The experimental setup employs successive measurements and repositioning of a base station at three different heights of 0.5, 1 and 1.5 m, and is accompanied by an extensive theoretical analysis of propagation, including line of sight, diffraction, and wall reflection. Enhancing the tutorial value of this work, a correlation analysis using Pearson's coefficient and root mean square error is performed between the field test and simulation results.

Narrating oneself and “putting in common”: life history and proximity communication

Resumo O artigo reflete o método História de vida, na perspectiva da comunicação de proximidade, desenvolvido como aprofundamento teórico-metodológico na tese “Proximidade e confissões: experiências em situação de rua e a construção de si. Histórias de vida e resistência no Centro Antigo de Salvador, Bahia”. Na confluência desses dispositivos metodológicos paradoxais foram evidenciados os aspectos “do encontro de mundos” e “a verdade do outro”, possibilitando avaliar o peso atribuído à sensibilidade, ao respeito pelo outro, e também à justa medida em se colocar, valorizando as situações dialógicas entre narradores e pesquisador, envolvidas na pesquisa qualitativa.

Narrar-se e “pôr em comum”: história de vida e comunicação de proximidade

Abstract This paper reflects the life history method, from a proximity communication approach, further elaborated in-depth as a theoretical-methodological frame of reference in the thesis “Proximity and confessions: experiences in homelessness and building of oneself. Life histories and resistance in Historic Downtown Salvador, Bahia”. At the interception of these paradoxical methodological frameworks, the aspects of “the meeting of worlds” and “the truth of the other” were highlighted, thus enabling an assessment of the role assigned to sensitivity, respect for the other and the fair extent to which one places oneself, while also valuing the dialogic contexts between narrators and the researcher embodied in qualitative research.

Joint resource and power allocation for 5G enabled D2D networking with NOMA

Paramount data transfer among users in social groups and concerts imposes enormous traffic at the base station (BS), depleting the available resources and forcing fifth-generation (5G) researchers to seek communion with alternative technologies. Non-Orthogonal Multiple Access (NOMA) is determined as a potential technology for supporting multiple users on the same sub-channels using power domain multiplexing. Integration of NOMA with a Device-to-Device (D2D) communication technology provides lower latency for supporting proximity communication. Significant research has been carried out till date in device pairing for resource allocation in NOMA and D2D. This paper proposes a joint resource and power allocation in the NOMA (JRPAN) algorithm for resource and power allocation to cellular and D2D users. Resources and power are adaptively assigned to the users depending upon the user's application. A proposal of group formation for resource reuse in NOMA with prioritized user application is established. The Simulations have been performed to ascertain the fair allocation of resources to the users in conformity to the application. The proposed algorithm helps in conserving power as compared to orthogonal frequency division multiplexing (OFDMA) with the Hidden Markov Model (HMM). The results demonstrate that JRPAN achieves higher system throughput and saves power while ensuring the requirement of Quality of Experience and Quality of service in comparison to OFDMA-HMM and proportional algorithm.

Isolation of extracellular vesicles from bitch’s amnion-derived cells culture and their CD59 expression: Preliminary results

Extracellular vesicles (EVs) are small spherical particles surrounded by a membrane with an unusual lipid composition and a striking cholesterol/phospholipidic ratio. About 2000 lipid and 3500 protein species were identified in EVs secreted by different cell sources. EVs mediate cell to cell communication in proximity to or distant from the cell of origin. In particular, it was suggested that they represent modulators of multiple processes during pregnancy.The aim of this study was to identify the presence of EVs in canine amnion-derived cells (ASCs) culture and the expression of CD 59 on their surface. Amniotic membrane was collected in PBS with antibiotics added from 2 bitches during elective caesarean section. Cells culture was prepared and EVs were isolated. EVs were used to evaluate CD59 expression by flow cytofluorimetry. We found that the majority of EVs expressed CD59. Our results could increase the knowledge about the complex mechanisms that regulate the pregnancy in the bitch.

Promoting health literacy during Covid-19 pandemic–valuable partnership with Portuguese pharmacists

Abstract Issue/Problem COVID-19 pandemic has amplified the amount of health information available; however, hard-to-reach populations remain and much of the information available is not accurate. Therefore, the use of new proximity approaches in the promotion of health literacy is essential because people face challenges and barriers when trying to find information relevant to them. Description of the problem From the beginning of the COVID-19 pandemic in 2020, the Division of Literacy, Health and Wellbeing of the Directorate-General of Health in Portugal developed Social Mobilization and Community Engagement training sessions-which included a presentation and a toolkit of flyers/posters/videos. These sessions had the goal of disseminating public health measures through good practices in health literacy and communication methods/skills to promote efficient communication among people who play an active role (as microinfluencers) in prevention and mitigation of risks associated with COVID-19, as is the case of pharmacists. Results A total of 200 Portuguese pharmacists enrolled on the Social mobilization training session in November 2021. More than 150 initiatives were implemented thereafter by those microinfluencers (pharmacists) in the local communities-31% directed to children or young people, 31% to older adults, and 13.8% to migrants or tourists. 70% of the participants considered the materials of the toolkit as adequate and sufficient, and 62.1% answered that people in the community showed interest for those materials available in the pharmacies. Lessons This Social mobilization project was important because it assembled and preserved trust- basing the information of the training on reliable sources about COVID-19 virus. It also trained the microinfluencers (pharmacists) in communication strategies. All these approaches were important to prevent and mitigate the impact of COVID-19 via adoption of non-pharmacological measures and promotion of vaccination. Key messages • Portugal was pioneer in promoting Social mobilization and community engagement training sessions, maintaining a proximity communication, tailoring the information, and maximizing its impact. • Within the group of health professionals, pharmacists are a privileged group to promote these communication strategies and social mobilization due to their proximity with the local community.

Overview of ultra-wideband transceivers—system architectures and applications

The Ultra-WideBand (UWB) technique, which offers good energy efficiency, flexible data rate, and high ranging accuracy, has recently been recognized as a revived wireless technology for short distance communication. This paper presents a brief overview of two UWB techniques, covering Impulse-Radio UWB (IR-UWB) and Frequency-Modulation UWB (FM-UWB) methods. The link margin enhancement technique, Very-WideBand (VWB), and power consumption reducing technique, chirp UWB, are also introduced. Then, several potential applications of IR-UWB with transceiver architectures are addressed, including high data rate proximity communication and secure wireless connectivity. With fine-ranging and energy-efficient communication features, the UWB wireless technology is highly promising for secure mobile Internet of Things (IoT) applications.

Use of Senegalese music to raise coronavirus awareness on social media

Senegal is a country with a long history of oral tradition, where the griot is the leading figure responsible for the transmission of messages from generation to generation over centuries. They are highly regarded and considered in society as a mediator and advisor through their music or spoken word. As Senegal witnessed the arrival of the first cases of coronavirus, a large number of musicians used social media to disseminate songs raising coronavirus awareness. Following these first initiatives, President Macky Sall met with several acclaimed musicians in the country. This led to the production of a polyphonic song released by the social media platforms of the Ministry of Health and Social Action. This article looks at music as an ‘edutaining’ and phenomenologically proximate communication strategy to raise awareness about coronavirus and the measures that can be taken to prevent its spread.

Integration of multi access edge computing with unmanned aerial vehicles: Current techniques, open issues and research directions

During the last decade, research and development in the field of multi access edge computing (MEC) has rapidly risen to prominence. One of the factors propelling MEC’s evolution is the ability to deploy edge servers capable of providing both communication and computational services in close proximity to the mobile user terminal. MEC has been regarded as a potentially transformative technique for fifth-generation (5G) and beyond 5G (B5G) wireless communication systems, as well as a possible complement to traditional cloud computing. Additionally, unmanned aerial vehicles (UAVs) integrated with MEC will play a critical role by introducing an additional mobility based computational layer to provide more secure, efficient and faster services. UAV enabled MEC offers seamless connectivity, fulfilling the promise of 5G’s ubiquitous connectivity. Due to the enormous interest in UAV enabled MEC, there has been a tremendous increase in the number of published research articles in this domain; however, the research area still lacks a systematic study and categorization. We present a systematic literature review (SLR) on UAV enabled MEC, examining and analyzing data on the current state of the art using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. To streamline our assessment, this study analyzes several research papers carefully selected through a multi-stage process satisfying the eligibility criteria defined in the paper. One of the SLR’s primary contributions is to broadly classify the research in the UAV enabled MEC domain into different categories including energy efficiency, resource allocation, security, architecture, and latency. We have identified key findings, technology, and pros and cons for the selected articles under each category. Additionally, we discuss the key open issues related to scalability and fairness, resource allocation and offloading optimization, service delivery with a focus on quality of experience (QoE) and quality of service (QoS), and standardization. Finally, we discuss several future research directions that would address the aforementioned issues and emerging use cases for UAV enabled MEC.

Robust Decentralized Cooperative Resource Allocation for High-Dense Robotic Swarms by Reducing Control Signaling Impact

High throughput, low latency, and high reliability in proximity communications for swarm robotics can be achieved using decentralized cooperative resource allocation schemes. These cooperative schemes minimize the occurrence of half-duplex problems, reduce interference, and allow a significant increase in the achievable swarm density, but requires additional signaling overhead, which makes them potentially more prone to performance degradation under realistic operation conditions. These conditions include both data, signaling, and their interdependence evaluated jointly. The negative impact of the signaling errors requires incorporating enhancement techniques to realize the full potential of the cooperative schemes. Particularly, in this paper and for this purpose, we evaluate the effects of hybrid automatic repeat request (HARQ), link adaptation by aggregation (LAAG) and beam selection by using directional antennas in the cooperative schemes, and compare performance with 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><i>rd</i></sup> Generation Partnership Project (3GPP) NR sidelink mode 2 (including signaling) using the same techniques. Additionally, we include a comparison of the required number of control signals between sidelink mode 2 inter-UE coordination (IUC) and cooperative schemes, and introduce a decentralized rebel sub-mode behavior in our group scheduling scheme to further improve the performance at the 99.99 percentile. The simultaneous use of all these enhancement techniques in our cooperative schemes considerably reduces the impact of signaling errors and thereby increases the supported swarm size compared to sidelink mode 2.

Double is not always better: rare cause of chronic pain and weight loss in an Asian woman with an anomaly of the bile duct system

A 42-year-old Asian woman with weight loss and recurring epigastric postprandial pain was admitted to our hospital with suspicion of chronic cholecystitis. The CT scan displayed a constriction of the gallbladder. Laboratory results were normal. Endoscopic retrograde cholangiography revealed a duplication of the extrahepatic bile duct (A-D) type 5b according to Choi featuring a common distal drainage tract into the major duodenal papilla and a proximal communication channel (A, D, arrow). Balloon-occluded cholangiography additionally showed an anomalous cystic dilatation of the cystic duct (B, C, arrow), thus mimicking a constriction of the gallbladder.

A distributed algorithm to maintain a proximity communication network among mobile agents using the Delaunay triangulation

This paper addresses the maintenance of a communication network in which mobile agents are connected to their nearest neighbours. While all agents are able to move individually, the geometrical relation to each other changes along their trajectories. The main idea is to develop distributed algorithms which enable the agents to monitor and to switch communications links in real time so that the overall network topology equals a Delaunay triangulation at any time. It is shown which information has to be stored locally by each agent and exchanged among the agents via digital communication. The paper closes with an experimental evaluation of the proposed methods.

Game based robust power allocation strategy with QoS guarantee in D2D communication network

Device to device (D2D) communication, as a proximity communication technique that leverages the spatial–temporal locality of mobile data usage to achieve one to many simultaneous transmission, provides an effective solution for unloading heavy traffic. However, due to the sharing of spectrum resources, interference management has become a major challenge for D2D communication. In this paper, a game-based robust power allocation strategy with quality of service (QoS) guarantee is designed for D2D multicast network. A Stackelberg game is proposed to characterize the actions of the base station (BS) and D2D users (DUEs). In the game, the BS is seen as the leader, whereas the D2D users are followers. On the one hand, the purpose of BS is to maximize the leader’s profit with the constraint of the maximum tolerable interference. On the other, the DUEs attempt to maximize the followers’ profit in the network system while guaranteeing the QoS requirements for DUEs, which are modeled as probability constraints. Spectrum sharing is assumed among the cellular users (CUEs) and DUEs. Because of the dynamic characteristics of wireless channel, it is difficult and expensive to acquire accurate channel state information (CSI). On this account, the uncertain channel state information is considered in the formulated problem, and the probability threshold method is utilized to convert the uncertain constraints into tractable ones. Furthermore, a distributed algorithm to determine the optimal solutions is proposed, which significantly reduces the information exchanges. Finally, numerical results validate the performances of the proposed scheme in the aspects of convergence, utility of uses, and power consumption.

Theoretical Analysis of Multi Integrating RX Front-Ends for Lossy Broad-Band Channels

Recent advances in wire-like communication channels without a physical wire has seen the emergence of wireline-like broadband channels but with atypical high loss. Communication links using such channels (e.g., Proximity Communication, Human Body Communication) are typically broadband, like wireline systems but noise-limited like wireless systems. Hence, employing broad-band communication through such emerging channels calls for new research on analyzing, designing and finding the theoretical limits for receiver topologies suitable for lossy broad-band channels . In this paper, we present a theoretical analysis framework for various broadband receivers in combination with low-noise amplifiers and proposed multi-integrator cascade, which provides significant gain with relatively lower power consumption than the standard gain elements. Through 1) derivation of new noise analysis of integrating-sampling receivers, 2) proposal of a new circuit topology (multi-integrating receiver, MIR) and 3) development of a thorough design space exploration framework, including use of a combination of wireless-inspired Low-noise amplifiers (LNA) with wireline-inspired strong-ARM latches, and the newly proposed MIRs, this paper demonstrates the optimum design choices for some common scenarios. Maximum achievable data rate and optimum energy-efficiency for various channel losses have been obtained theoretically for different topologies revealing their advantages and limitations, intended to serve as a guide for future receiver designs for lossy broad-band channels . All the circuits have been designed in 65 nm CMOS process with a 1 V supply voltage.

CDERSA: Cognitive D2D Enabled Relay Selection Algorithm to Mitigate Blind-Spots in 5G Cellular Networks

Blind-spots, where wireless signals do not reach within the coverage range, often emerge in a dynamic environment due to obstacles, geographical location or mobility of cellular users (CUs). Thus greatly reducing the overall system performance in terms of coverage and throughput. Relay-aided cognitive Device to Device (cD2D) communication system underlying the 5G cellular network can help mitigate blind-spots. Cognitive capability helps D2D users to acquire the spectrum opportunistically for proximity communication and establish a semi-independent network underlying the 5G network, which not only offloads 5G-New Radio (NR) base station but also enhances the overall system performance. In this work, we have developed a relay-aided cognitive D2D network that helps CUs falling into the blind-spots to retain access to the 5G network and increase wireless coverage. Relay selection requires mutual consent between the relay and the device in the blind-spot. The in-coverage devices are tempted to act as relays through incentive-based mechanism. For enhanced system performance a suitable match among the devices in blind-spots and the relays is required. cD2D enabled relay selection algorithm (cDERSA) is proposed in this work, in which a cognitive D2D user (cDU), which is a CU falling in the blind-spot, establishes a relayed cD2D link to access 5G-NR gNodeB. All cDUs as well as the tempted relays, i.e. cognitive D2D relays (cDRs), first scan their surroundings for devices capable of D2D communication and based on multi-criteria objective functions, build a priority table. A stable marriage problem is formulated and solved using a unique, stable, distributed, and efficient matching algorithm based on the Gale-Shapley algorithm. A new incentive mechanism is also developed to keep relays motivated to share their resources. Simulation is performed and their results show improvement in throughput and average user satisfaction, which validates our proposed cDERSA.

The Biological Function of Extracellular Vesicles during Fertilization, Early Embryo-Maternal Crosstalk and Their Involvement in Reproduction: Review and Overview.

Secretory extracellular vesicles (EVs) are membrane-enclosed microparticles that mediate cell to cell communication in proximity to, or distant from, the cell of origin. Cells release a heterogeneous spectrum of EVs depending on their physiologic and metabolic state. Extracellular vesicles are generally classified as either exosomes or microvesicles depending on their size and biogenesis. Extracellular vesicles mediate temporal and spatial interaction during many events in sexual reproduction and supporting embryo-maternal dialogue. Although many omic technologies provide detailed understanding of the molecular cargo of EVs, the difficulty in obtaining populations of homogeneous EVs makes difficult to interpret the molecular profile of the molecules derived from a miscellaneous EV population. Notwithstanding, molecular characterization of EVs isolated in physiological and pathological conditions may increase our understanding of reproductive and obstetric diseases and assist the search for potential non-invasive biomarkers. Moreover, a more precise vision of the cocktail of biomolecules inside the EVs mediating communication between the embryo and mother could provide new insights to optimize the therapeutic action and safety of EV use.

Deep Learning-Based Power Control Scheme for Perfect Fairness in Device-to-Device Communication Systems

The proximity-based device-to-device (D2D) communication allows for internet of things, public safety, and data offloading services. Because of these advantages, D2D communication has been applied to wireless communication networks. In wireless networks using D2D communication, there are challenging problems of the data rate shortage and coverage limitation due to co-channel interference in the proximity communication. To resolve the problems, transmit power control schemes that are based on deep learning have been presented in network-assisted D2D communication systems. The power control schemes have focused on enhancing spectral efficiency and energy efficiency in the presence of interference. However, the data-rate fairness performance may be a key performance metric in D2D communications, because devices in proximity can expect fair quality of service in the system. Hence, in this paper, a transmit power control scheme using a deep-learning algorithm based on convolutional neural network (CNN) is proposed to consider the data-rate fairness performance in network-assisted D2D communication systems, where the wireless channels are modelled by path loss and Nakagami fading. In the proposed scheme, the batch normalization (BN) scheme is introduced in order to further enhance the spectral efficiency of the conventional deep-learning transmit power control scheme. In addition, a loss function for the deep-learning optimization is defined in order to consider both the data-rate fairness and spectral efficiency. Through simulation, we show that the proposed scheme can achieve extremely high fairness performance while improving the spectral efficiency of the conventional schemes. It is also shown that the improvement in the fairness and spectral efficiency is achieved for different Nakagami fading conditions and sizes of area containing the devices.