bluuebunny/crossref_metadata_2025 huggingface dataset:
Noble Metal-Based Catalysts with Core-Shell Structure for Oxygen Reduction Reaction: Progress and Prospective
Authors: Wang Chao , An Cuihua , Qin Chunling , Gomaa Hassanien , Deng Qibo , Wu Shuai , Hu Ning
Published: July 2022

With the deterioration of the ecological environment and the depletion of fossil energy, fuel cells, representing a new generation of clean energy, have received widespread attention. This review summarized recent progress in noble metal-based core–shell catalysts for oxygen reduction reactions (ORRs) in proton exchange membrane fuel cells (PEMFCs). The novel testing methods, performance evaluation parameters and research methods of ORR were briefly introduced. The effects of the preparation method, temperature, kinds of doping elements and the number of shell layers on the ORR performances of noble metal-based core–shell catalysts were highlighted. The difficulties of mass production and the high cost of noble metal-based core–shell nanostructured ORR catalysts were also summarized. Thus, in order to promote the commercialization of noble metal-based core–shell catalysts, research directions and prospects on the further development of high performance ORR catalysts with simple synthesis and low cost are presented.
Influence of Diet and Lifestyle on the Development of Gestational Diabetes Mellitus and on Perinatal Results
Authors: Yuste Gómez Alba , Ramos Álvarez Maria del Pilar , Bartha José Luis
Published: July 2022

GDM is a multifactorial disease, so there is controversy regarding the mechanisms involved in its pathogenesis. We speculate whether lifestyle and eating habits influenced the appearance and pathogenesis of GDM. To explore this issue, the aim of the present study was to analyze maternal diet and lifestyle characteristics in early pregnancy and their influence on the development of GDM. The study included 103 pregnant women who completed a questionnaire on nutritional knowledge, lifestyle and eating habits. Perinatal and biochemical outcomes as well as pregestational lifestyle and eating habits were compared between normoglycemic women and those who developed GDM. The results obtained showed that women who developed GDM had erroneous knowledge regarding nutrition. Consumption of white bread (p = 0.018), added sugars (p = 0.037), legumes (p = 0.025), fish (p = 0.014), butter (p = 0.010) and the performance of less physical activity (p = 0.024) correlated with glucose intolerance in pregnant women. In conclusion, we found a relationship between dietary and lifestyle habits at the beginning of pregnancy and the later diagnosis of GDM.
The Mediterranean Diet: An Update of the Clinical Trials
Authors: Finicelli Mauro , Di Salle Anna , Galderisi Umberto , Peluso Gianfranco
Published: July 2022

The Mediterranean Diet (MedDiet) is a term used to identify a dietary pattern originating from the unique multi-millennial interplay between natural food resources and the eating practices of people living in the Mediterranean basin. Scientific evidence has described the healthy properties of the MedDiet and its beneficial role in several pathological conditions. Nevertheless, current socio-economic trends have moved people away from this healthy lifestyle. Thus, clinical and biological evidence supporting the benefits of the MedDiet is needed to overcome these limitations. Clinical nutrition research examines the effects of dietary interventions on biological or health-related outcomes in a determined study population. The evidence produced by these studies is useful for dietary guidance and public health messaging. We provided an update of the clinical trials registered on the database clinicaltrials.gov evaluating the effects of the MedDiet on health and specific diseases. Our findings revealed an increased number of clinical trials in the last decade and found that most disease-related studies focused on cardiovascular diseases, metabolic diseases, and cancer. The majority of MedDiet’s beneficial effects could be primarily related to its anti-inflammatory and anti-oxidant properties as well as the effectiveness of this dietary pattern in controlling waist circumference and obesity. Moreover, strict and long-lasting adherence to the MedDiet as well as the beneficial effects of specific components (e.g., olive oil or its polyphenols) seem to emerge as useful insights for interventional improvements. These findings present further insights into the MedDiet’s resources and how it could strengthen overall public health.
Timing of Breastfeeding Initiation Mediates the Association between Delivery Mode, Source of Breastfeeding Education, and Postpartum Depression Symptoms
Authors: Shen Xinran , Lin Shunna , Li Hui , Amaerjiang Nubiya , Shu Wen , Li Menglong , Xiao Huidi , Segura-Pérez Sofia , Pérez-Escamilla Rafael , Fan Xin , Hu Yifei
Published: July 2022

Background: Emergency cesarean section (EMCS) and breastfeeding difficulties increase the risk of postpartum depressive (PPD) symptoms. Early initiation of breastfeeding (EIBF) may not only alleviate PPD symptoms but also facilitate subsequent breastfeeding success. EMCS is a risk factor for not practicing EIBF. Therefore, it is important to understand the relationship between EMCS, EIBF, and PPD symptoms. Methods: We conducted a prospective cohort study in three areas of China. At baseline, a total of 965 mothers completed electronic questionnaires within 72 h postpartum. Women were screened for PPD symptoms using the Edinburgh Postpartum Depression Scale (EPDS). Multivariate logistic regression was used to identify the determinants of PPD symptoms. Mediation analysis was used to determine if EIBF mediated the relationship between delivery mode or breastfeeding education source and PPD symptoms. Results: The prevalence of EIBF was 40.6%; 14% of 965 mothers experienced EMCS, and 20.4% had PPD symptoms. The risk factors for developing PPD symptoms were excessive gestational weight gain (adjusted odds ratio [aOR] = 1.55, confidence interval [95% CI]: 1.03–2.33, p = 0.037) and EMCS (aOR = 2.05, 95% CI: 1.30–3.25, p = 0.002). The protective factors for developing PPD symptoms were monthly household income over CNY 10000 (aOR = 0.68, 95% CI: 0.47–0.97, p = 0.034), EIBF (aOR = 0.49, 95% CI: 0.34–0.72, p < 0.001), and prenatal breastfeeding education from nurses (aOR = 0.46, 95% CI: 0.29–0.73, p = 0.001). EIBF indirectly affected PPD symptoms in patients who had undergone EMCS (percentage mediated [PM] = 16.69, 95% CI: 7.85–25.25, p < 0.001). The source of breastfeeding education through EIBF also affected PPD symptoms (PM = 17.29, 95% CI: 3.80–30.78, p = 0.012). Conclusion: The association between EMCS on PPD symptoms was mediated by EIBF. By providing breastfeeding education, nurses could also help alleviate PPD symptoms.
The Glenoid Track Concept: On-Track and Off-Track—A Narrative Review
Authors: Ventura Antonio , Smiraglio Claudia , Viscomi Antonio , De Salvatore Sergio , Bertucci Bernardo
Published: July 2022

Shoulder instability is described as a functional deficiency caused by excessive mobility of the humeral head over the glenoid. Various Glenohumeral Instability (GI) types have been described, but the traumatic anteroinferior form is the most frequent. The differences between engaging and non-engaging Hill–Sachs lesions (HSLs) are linked to bone loss assessment. On the contrary, the novel difference between “on-track” and “off-track” lesions is strictly related to surgical techniques. The specific involvement of glenoid and humerus bone defects in recurrent GI was poorly assessed in the literature before the glenoid-track concept (GT). Magnetic Resonance Imaging (MRI) and Arthro-MRI have been widely used to identify and characterize lesions to the ligamentous structures. However, only new technologies (3 Tesla MRI) accurately detect HSLs. On the contrary, Computed Tomography (CT) has been adopted to quantify glenoid bone deficit. The GT concept is a valuable tool for evaluating anterior shoulder instability in patients. Shoulders out of alignment may require more than just an arthroscopic Bankart, and a remplissage or bone transfer may be necessary. Specifically, isolated Bankart repair should be considered in patients with recurrent instability and an on-track lesion with less than 25% glenoid bone loss. In off-track lesions and less than 25% glenoid bone loss, remplissage should be used. Bone transplant surgery is required for patients with a glenoid bone defect of more than 25%. This narrative review aims to report the most updated findings on “on-track” and “off-track” lesions in GI.
Molecular Epidemiology and Baseline Resistance of Hepatitis C Virus to Direct Acting Antivirals in Croatia
Authors: Simicic Petra , Slovic Anamarija , Radmanic Leona , Vince Adriana , Zidovec Lepej Snjezana
Published: July 2022

Molecular epidemiology of hepatitis C virus (HCV) is exceptionally complex due to the highly diverse HCV genome. Genetic diversity, transmission dynamics, and epidemic history of the most common HCV genotypes were inferred by population sequencing of the HCV NS3, NS5A, and NS5B region followed by phylogenetic and phylodynamic analysis. The results of this research suggest high overall prevalence of baseline NS3 resistance associate substitutions (RAS) (33.0%), moderate prevalence of NS5A RAS (13.7%), and low prevalence of nucleoside inhibitor NS5B RAS (8.3%). Prevalence of RAS significantly differed according to HCV genotype, with the highest prevalence of baseline resistance to NS3 inhibitors and NS5A inhibitors observed in HCV subtype 1a (68.8%) and subtype 1b (21.3%), respectively. Phylogenetic tree reconstructions showed two distinct clades within the subtype 1a, clade I (62.4%) and clade II (37.6%). NS3 RAS were preferentially associated with clade I. Phylogenetic analysis demonstrated that 27 (9.0%) HCV sequences had a presumed epidemiological link with another sequence and classified into 13 transmission pairs or clusters which were predominantly comprised of subtype 3a viruses and commonly detected among intravenous drug users (IDU). Phylodynamic analyses highlighted an exponential increase in subtype 1a and 3a effective population size in the late 20th century, which is a period associated with an explosive increase in the number of IDU in Croatia.
Role of Microglia in Herpesvirus-Related Neuroinflammation and Neurodegeneration
Authors: Patrycy Magdalena , Chodkowski Marcin , Krzyzowska Malgorzata
Published: July 2022

Neuroinflammation is defined as an inflammatory state within the central nervous system (CNS). Microglia conprise the resident tissue macrophages of the neuronal tissue. Upon viral infection of the CNS, microglia become activated and start to produce inflammatory mediators important for clearance of the virus, but an excessive neuroinflammation can harm nearby neuronal cells. Herpesviruses express several molecular mechanisms, which can modulate apoptosis of infected neurons, astrocytes and microglia but also divert immune response initiated by the infected cells. In this review we also describe the link between virus-related neuroinflammation, and development of neurodegenerative diseases.
Analgesic and Anesthetic Efficacy of Rocuronium/Sugammadex in Otorhinolaryngologic Surgery: A Propensity Score-Matched Analysis
Authors: Wu En-Bo , Hung Chao-Ting , Luo Sheng-Dean , Wu Shao-Chun , Lee Tsung-Yang , Chin Jo-Chi , Tsai Peng-Neng , Yang Johnson Chia-Shen
Published: July 2022

The use of rocuronium/sugammadex in otorhinolaryngologic surgery improves intubation conditions and surgical rating scales. This study primarily aimed to evaluate the effect of the combination of rocuronium and sugammadex on intraoperative anesthetic consumption. The secondary outcomes were the intraoperative and postoperative morphine milligram equivalent (MME) consumption, duration of intraoperative hypertension, extubation time, incidence of delayed extubation and postoperative nausea and vomiting, pain score, and length of stay. A total of 2848 patients underwent otorhinolaryngologic surgery at a tertiary medical center in southern Taiwan. After applying the exclusion criteria, 2648 of these cases were included, with 167 and 2481 in the rocuronium/sugammadex and cisatracurium/neostigmine groups, respectively. To reduce potential bias, 119 patients in each group were matched by propensity scores for sex, age, body weight, and type of surgery. We found that the rocuronium/sugammadex group was associated with significant preservation of the intraoperative sevoflurane and MME consumption, with reductions of 14.2% (p = 0.009) and 11.8% (p = 0.035), respectively. The use of the combination of rocuronium and sugammadex also significantly increased the dose of intraoperative labetalol (p = 0.002), although there was no significant difference in intraoperative hypertensive events between both groups. In conclusion, our results may encourage the use of the combination of rocuronium and sugammadex as part of volatile-sparing and opioid-sparing anesthesia in otorhinolaryngologic surgery.
Perfluorocarbon Nanodroplets as Potential Nanocarriers for Brain Delivery Assisted by Focused Ultrasound-Mediated Blood–Brain Barrier Disruption
Authors: Bérard Charlotte , Desgranges Stéphane , Dumas Noé , Novell Anthony , Larrat Benoit , Hamimed Mourad , Taulier Nicolas , Estève Marie-Anne , Correard Florian , Contino-Pépin Christiane
Published: July 2022

The management of brain diseases remains a challenge, particularly because of the difficulty for drugs to cross the blood–brain barrier. Among strategies developed to improve drug delivery, nano-sized emulsions (i.e., nanoemulsions), employed as nanocarriers, have been described. Moreover, focused ultrasound-mediated blood–brain barrier disruption using microbubbles is an attractive method to overcome this barrier, showing promising results in clinical trials. Therefore, nanoemulsions combined with this technology represent a real opportunity to bypass the constraints imposed by the blood–brain barrier and improve the treatment of brain diseases. In this work, a stable freeze-dried emulsion of perfluorooctyl bromide nanodroplets stabilized with home-made fluorinated surfactants able to carry hydrophobic agents is developed. This formulation is biocompatible and droplets composing the emulsion are internalized in multiple cell lines. After intravenous administration in mice, droplets are eliminated from the bloodstream in 24 h (blood half-life (t1/2) = 3.11 h) and no long-term toxicity is expected since they are completely excreted from mice’ bodies after 72 h. In addition, intracerebral accumulation of tagged droplets is safely and significantly increased after focused ultrasound-mediated blood–brain barrier disruption. Thus, the proposed nanoemulsion appears as a promising nanocarrier for a successful focused ultrasound-mediated brain delivery of hydrophobic agents.
The Influence of Plant Stress Hormones and Biotic Elicitors on Cyclotide Production in Viola uliginosa Cell Suspension Cultures
Authors: Slazak Blazej , Jędrzejska Aleksandra , Badyra Bogna , Shariatgorji Reza , Nilsson Anna , Andrén Per E. , Göransson Ulf
Published: July 2022

Cyclotides are macrocycle peptides produced by plants from several families, including Violaceae. These compounds have the potential for applications in medicine, bioengineering and crop protection thanks to their multiple biological activities. In most cases, cyclotides are extracted from plant material. Plant cell culture provides a viable and sustainable form of plant biomass production Cyclotides are host defense peptides. The aim of the current study was to test whether different plant stress hormones and biological elicitors have effects on cyclotide production in Viola uliginosa suspension cultures. Different concentrations of jasmonic acid (JA), salicylic acid (SA), abscisic acid (ABA) and neutralized pathogens were tested. The cyclotide production was assessed using MALDI-MS. Five major peptides produced by V. uliginosa cultures were chosen for analysis, of which one was sequenced de novo. The treatments had little influence on the suspension’s growth, with the exception of 100 μM SA, which enhanced the biomass increase, and 100 μM ABA, which was toxic. Significant increases in the production of three cyclotides (viul M, cyO13 and cyO3) were observed in suspensions primed with JA (50 μM, 100 μM, 200 μM) after 14 days of culturing. Biotic elicitors had no observable effect on cyclotide production. The current study indicates that some cyclotides in V. uliginosa are triggered in response to JA. The stress plant hormones can be used to enhance plant cell culture-based production systems.
The Warps and Wefts of a Polyploidy Complex: Integrative Species Delimitation of the Diploid Leucanthemum (Compositae, Anthemideae) Representatives
Authors: Ott Tankred , Schall Maximilian , Vogt Robert , Oberprieler Christoph
Published: July 2022

Species delimitation—owing to the paramount role of the species rank in evolutionary, ecological, and nature conservation studies—is an essential contribution of taxonomy to biodiversity research. In an ‘integrative taxonomy’ approach to species delimitation on the diploid level, we searched for evolutionary significant units (the warps and wefts) that gave rise to the polyploid complex of European ox-eye daisies (Leucanthemum; Compositae-Anthemideae). Species discovery and validation methods based on genetic, ecological, geographical, and morphometric datasets were applied to test the currently accepted diploid morpho-species, i.e., morphologically delimited species, in Leucanthemum. Novel approaches were taken in the analyses of RADseq data (consensus clustering), morphometrics of reconstructed leaf silhouettes from digitized herbarium specimens, and quantification of species-distribution overlaps. We show that 17 of the 20 Leucanthemum morpho-species are supported by genetic evidence. The taxonomic rank of the remaining three morpho-species was resolved by combining genealogic, ecologic, geographic, and morphologic data in the framework of von Wettstein’s morpho-geographical species concept. We herewith provide a methodological pipeline for the species delimitation in an ‘integrative taxonomy’ fashion using sources of evidence from genealogical, morphological, ecological, and geographical data in the philosophy of De Queiroz’s “Unified Species Concept”.
Identification of Putative Candidate Genes from Galphimia spp. Encoding Enzymes of the Galphimines Triterpenoids Synthesis Pathway with Anxiolytic and Sedative Effects
Authors: Iglesias Dianella , Donato Capote Marcos de , Méndez Tenorio Alfonso , Valdivia Ana Victoria , Gutiérrez-García Claudia , Paul Sujay , Iqbal Hafiz M. N. , Villarreal María Luisa , Sharma Ashutosh
Published: July 2022

Galphimia spp. is popularly used in Mexican traditional medicine. Some populations of Galphimia exert anxiolytic and sedative effects due to the presence of the modified triterpenoids galphimines. However, the galphimine synthesis pathway has not yet been elucidated. Hence, in this study, a comparative transcriptome analysis between two contrasting populations of Galphimia spp., a galphimine-producer, and a non-galphimine-producer, is performed using RNA-Seq in the Illumina Next Seq 550 platform to identify putative candidates genes that encode enzymes of this metabolic pathway. Transcriptome functional annotation was performed using the Blast2GO in levels of gene ontology. For differential expression analysis, edgeR, pheatmap, and Genie3 library were used. To validate transcriptome data, qPCR was conducted. In producer and non-producer plants of both populations of Galphimia spp., most of the transcripts were grouped in the Molecular Function level of gene ontology. A total of 680 differentially expressed transcripts between producer and non-producer plants were detected. In galphimine-producer plants, a larger number of highly expressed transcripts related to acyclic and polycyclic terpene synthesis were identified. As putative candidate genes involved in the galphimine synthesis pathway, P450 family members and enzymes with kinase activity were identified.
Compression and Bending Properties of Short Carbon Fiber Reinforced Polymers Sandwich Structures Produced via Fused Filament Fabrication Process
Authors: Zaharia Sebastian Marian , Pop Mihai Alin , Chicos Lucia-Antoneta , Buican George Razvan , Lancea Camil , Pascariu Ionut Stelian , Stamate Valentin-Marian
Published: July 2022

Additive manufacturing, through the process of thermoplastic extrusion of filament, allows the manufacture of complex composite sandwich structures in a short time with low costs. This paper presents the design and fabrication by Fused Filament Fabrication (FFF) of composite sandwich structures with short fibers, having three core types C, Z, and H, followed by mechanical performance testing of the structures for compression and bending in three points. Flatwise compression tests and three-point bending have clearly indicated the superior performance of H-core sandwich structures due to dense core structures. The main modes of failure of composite sandwich structures were analyzed microscopically, highlighting core shear buckling in compression tests and face indentation in three-point bending tests. The strength–mass ratio allowed the identification of the structures with the best performances considering the desire to reduce the mass, so: the H-core sandwich structures showed the best results in compression tests and the C-core sandwich structures in three-point bending tests. The feasibility of the FFF process and the three-point bending test of composite wing sections, which will be used on an unmanned aircraft, have also been demonstrated. The finite element analysis showed the distribution of equivalent stresses and reaction forces for the composite wing sections tested for bending, proving to validate the experimental results.
On the Mechanical Performance of Polylactic Material Reinforced by Ceramic in Fused Filament Fabrication
Authors: Hedjazi Lotfi , Guessasma Sofiane , Belhabib Sofiane , Stephant Nicolas
Published: July 2022

This study addresses the potential of using ceramics-based filaments as a feedstock material in an additive manufacturing process. Tensile specimens of PLA-ceramic (PLC) material are manufactured using a fused deposition modelling process, applying various printing parameters including printing angle and part orientation. Mechanical testing is performed on both the filaments and 3D-printed parts, and the related engineering quantities are derived. The experimental results show that PLC wire properties are substantially restored for the horizontal and lateral printing orientations, with only a 9% reduction in stiffness. In addition, a typical elastic-plastic response is achieved with these orientations, allowing the PLC to achieve excellent stiffness and elongation-at-break performance. The mechanical performance of the PLC is explained by the large proportion of continuous filaments along the loading direction. In addition, the printing angle is found to be a secondary factor allowing for layups at −45°/+45° and 0°/90°, resulting in the best tensile performance. The downside of using PLC is the lack of mechanical transfer, which is associated with weak interfacial behaviour and the inability to achieve high tensile strength.
The Use of Carbon Fibers Recovered by Pyrolysis from End-of-Life Wind Turbine Blades in Epoxy-Based Composite Panels
Authors: Smoleń Jakub , Olesik Piotr , Jała Jakub , Adamcio Andrzej , Kurtyka Klaudia , Godzierz Marcin , Kozera Rafał , Kozioł Mateusz , Boczkowska Anna
Published: July 2022

This work is devoted to evaluating the effectiveness of the recovery of carbon fibers from end-of-life wind turbine blades in the pyrolysis process, and the use of those fibers in the production of flat composite panels. The recovery of carbon fibers from wind turbine blades uses a pyrolysis process at 500–600 °C in a non-oxidizing atmosphere, in such a way that makes it possible to preserve the shape and dimensions of the fibers. Using recycled carbon fibers, flat CFRP sheets with epoxy resin matrix were produced by pressing. Seven different series of samples were tested, which differed in fiber length, fiber orientation, and pressure holding time. The results obtained on the recycled fibers were compared to the original carbon fibers, cut to corresponding lengths. Additionally, one of the series was reinforced with a biaxial fabric. The most favorable pressing parameters are empirically found to be pre-pressing 2 MPa (10 min), and further pressing at a pressure of 7 MPa until the resin completely cross-linked (about 120 min). A number of tests were carried out to demonstrate the usefulness of pyrolytic fibers, including tensile strength of carbon fibers, bending strength, SEM observations, FT-IR, and Raman spectroscopy. The tests carried out on the carbon fibers show that the pyrolysis process used leaves about 2% of the matrix on the surface of the fiber, and the tensile strength of the fibers drops by about 20% compared to the new carbon fibers. The research results show that the use of the recycled carbon fibers in the production of flat composite plates is reliable, and their mechanical properties do not differ significantly from plates made of corresponding original carbon fibers. Composite panels with the pyrolytic fibers (274 MPa) show up to a 35% higher flexural strength than similarly produced panels with the original new carbon fibers (203 MPa), which means that the panels can be used in the production of elements for footbridges, bridges, pipelines, or structural elements of buildings and roofing.
Continuous Nonsingular Fast Terminal Sliding Mode Control for Speed Tracking of PMSM Based on Finite Time Disturbance Observer
Authors: Yue Yaobin , Geng Yanfeng , Wang Weiliang
Published: July 2022

A continuous nonsingular fast terminal sliding mode (CNFTSM) control strategy with an automated double power reaching law is proposed to improve the performance of speed dynamic response and accuracy tracking for the permanent magnet synchronous motor (PMSM) servo system. In pursuit of robustness against system uncertainties, a finite-time convergent extended state observer (ESO) is designed to estimate external disturbances, parameter variation, and unmodeled dynamics as a feedforward compensation to the output feedback control system. The developed controller, based on Lyapunov stability theory analysis, can guarantee finite time stability from any initial state in the presence of internal and external disturbances. The modified sliding mode reaching law can achieve enough convergence rate compared with the exponential reaching law, and the inherent chattering of sliding mode is reduced when system states approach the equilibrium point. Theoretical analysis and simulation results demonstrate that the proposed composite controller can achieve higher performance than the conventional sliding mode method.
Skid Resistance Performance of Asphalt Mixtures Containing Recycled Pavement Materials under Simulated Weather Conditions
Authors: Pomoni Maria , Plati Christina
Published: July 2022

One of the challenges of using recycled materials in road structures is to maintain safe and durable pavements. A multitude of research has been conducted over the years on various recycled materials, with a focus on the structural performance of pavements. Another crucial, but almost overlooked, aspect is the pavement’s ability to provide adequate skid resistance for road users under different climatic conditions. With this in mind, the present study aimed to investigate the skid resistance of asphalt mixtures containing two different types of recycled materials under laboratory-simulated weather conditions. Conventional hot-mix asphalt (HMA) and mixtures containing either reclaimed asphalt pavement (RAP) for aggregate replacement or crumb rubber (CR) as a bitumen additive were prepared and tested at different temperatures and different surface conditions (i.e., dry/wet) following a wetting protocol. Skid resistance was measured using a British Pendulum Tester (BPT). The results showed that the recycled mixtures performed similarly to conventional ones in terms of the skid resistance when the temperature was varied and under variable simulated surface conditions too. In some cases, they performed even better than conventional mixtures. Overall, a promising potential is demonstrated towards the use of the investigated recycled materials in asphalt surface courses.
An Investigation of the Ice Cloud Detection Sensitivity of Cloud Radars Using the Raman Lidar at the ARM SGP Site
Authors: Wang Mingcheng , Balmes Kelly A. , Thorsen Tyler J. , Willick Dylan , Fu Qiang
Published: July 2022

The ice cloud detection sensitivity of the millimeter cloud radar (MMCR) and the Ka-band Zenith radar (KAZR) is investigated using a collocated Raman lidar (RL) at the Atmospheric Radiation Measurement Program Southern Great Plains site. Only profiles that are transparent to the RL with ice clouds only are considered in this study. The MMCR underestimates the RL ice cloud optical depth (COD) by 20%. The MMCR detects no ice clouds in 37% of the profiles. These profiles where ice cloud goes undetected by the MMCR typically contain very optically thin clouds, with a mean RL ice COD of 0.03. Higher ice cloud detection sensitivity is found for the KAZR, which underestimates the RL ice COD by 15%. The decrease in the ice COD bias for the KAZR compared to the MMCR is largely due to a decrease in the ice COD bias for the situation where the transparent profiles with ice clouds are detected by both the RL and cloud radar. The climatic net ice cloud radiative effects (CREs) from the RL at the top of the atmosphere (TOA) and the surface are 3.2 W m−2 and −0.6 W m−2, respectively. The ice CREs at the TOA and surface are underestimated for the MMCR by 0.7 W m−2 and 0.16 W m−2 (21% and 29%) and underestimated for the KAZR by 0.6 W m−2 and 0.14 W m−2 (17% and 24%). The ice clouds undetected by the cloud radars led to underestimating the climatic net cloud heating rates below 150 hPa by about 0–0.04 K day−1.
Wetland Hydroperiod Analysis in Alberta Using InSAR Coherence Data
Authors: Amani Meisam , Brisco Brian , Warren Rebecca , DeLancey Evan R. , Seydi Seyd Teymoor , Poncos Valentin
Published: July 2022

Wetlands are dynamic environments, the water and vegetation of which can change considerably over time. Thus, it is important to investigate the hydroperiod status of wetlands using advanced techniques such as remote sensing technology. Wetland hydroperiod analysis has already been investigated using optical satellite and synthetic aperture radar (SAR) backscattering data. However, interferometric SAR (InSAR) coherence products have rarely been used for wetland hydroperiod mapping. Thus, this study utilized Sentinel-1 coherence maps produced between 2017 and 2020 (48 products) to map the wetland hydroperiod over the entire province of Alberta, Canada. It was observed that a coherence value of 0.45 was an optimum threshold value to discriminate flooded from non-flooded wetlands. Moreover, the results showed that most wetlands were inundated less than 50% of the time over these four years. Furthermore, most wetlands (~40%) were seasonally inundated, and there was a small percentage of wetlands (~5%) that were never flooded. Overall, the results of this study demonstrated the high capability of InSAR coherence products for wetland hydroperiod analysis. Several suggestions are provided to improve the results in future works.
Monitoring Heat Extremes across Central Europe Using Land Surface Temperature Data Records from SEVIRI/MSG
Authors: Gouveia Célia M. , Martins João P. A. , Russo Ana , Durão Rita , Trigo Isabel F.
Published: July 2022

The frequency and intensity of extreme hot events have increased worldwide, particularly over the past couple of decades. Europe has been affected by unprecedented mega heatwaves, namely the events that struck Western Europe in 2003 and Eastern Europe in 2010. The year 2018 was also reported as an unusually hot year, with record-breaking temperatures in many parts of Europe during spring and summer, associated with severe and unusual wildfires and significant crop losses in central and northern Europe. We show the ability of Land Surface Temperature (LST), retrieved from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG) to monitor heat extremes, using the 2018 European event as a showcase. The monitoring approach relies on monthly anomalies performed as departures from the median and the monthly number of hot days (NHD), both computed for satellite LST derived from MSG and MODIS, and for 2 m air temperature (T2m) from ERA5 reanalysis, using as threshold the 90th percentiles. Results show strong monthly LST anomalies during the spring and summer of 2018 extending over central and north Europe. Over a vast region in Central and Northern Europe, LST reached the last 15 years high record. Moreover, those outstanding warm LSTs persisted for more than four months. Results obtained using MODIS LST and ERA5 T2m show similar patterns, which, although slightly less intense, corroborate the exceptionality of the heat extremes observed over central and northern Europe during 2018. The spatial pattern of the number of monthly record high anomalies over the MSG observations period clearly depicts the regions in Northern and Central Europe affected by the complex phenomena that occurred in 2018, which resulted from the combined effect of an extreme heatwave in spring and summer with extensive dry conditions. Therefore, the results highlighted the suitability of MSG LST to evaluate and monitor heat extremes alone or combined with dry and bright conditions and prompts the potential of other climate data records from geostationary satellites to characterize these climate extremes that could become the norm in the near future over central and northern Europe.
Bayesian Estimation of Land Deformation Combining Persistent and Distributed Scatterers
Authors: Li Gen , Ding Zegang , Li Mofan , Hu Zihan , Jia Xiaotian , Li Han , Zeng Tao
Published: July 2022

Persistent Scatterer Interferometry (PSI) has been widely used for monitoring land deformation in urban areas with millimeter accuracy. In natural terrain, combining persistent scatterers (PSs) and distributed scatterers (DSs) to jointly estimate deformation, such as SqueeSAR, can enhance PSI results for denser and better coverage. However, the phase quality of a large number of DSs is far inferior to that of PSs, which deteriorates the deformation measurement accuracy. To solve the contradiction between measurement accuracy and coverage, a Bayesian estimation method of land deformation combining PSs and DSs is proposed in this paper. First, a two-level network is introduced into the traditional PSI to deal with PSs and DSs. In the first-level network, the Maximum Likelihood Estimation (MLE) of deformation parameters at PSs and high-quality DSs is obtained accurately. In the secondary-level network, the remaining DSs are connected to the nearest PSs or high-quality DSs, and the deformation parameters are estimated by Maximum A Posteriori (MAP) based on Bayesian theory. Due to the poor phase quality of the remaining DSs, MAP can achieve better estimation results than the MLE based on the spatial correlation of the deformation field. Simulation and Sentinel-1A satellite data results verified the feasibility and reliability of the proposed method. Regularized by the spatial deformation field derived from the high-quality PSs and DSs, the proposed method is expected to achieve robust results even in low-coherence areas, such as rural areas, vegetation coverage areas, or deserts.
Drowsiness Detection System Based on PERCLOS and Facial Physiological Signal
Authors: Chang Robert Chen-Hao , Wang Chia-Yu , Chen Wei-Ting , Chiu Cheng-Di
Published: July 2022

Accidents caused by fatigue occur frequently, and numerous scholars have devoted tremendous efforts to investigate methods to reduce accidents caused by fatigued driving. Accordingly, the assessment of the spirit status of the driver through the eyes blinking frequency and the measurement of physiological signals have emerged as effective methods. In this study, a drowsiness detection system is proposed to combine the detection of LF/HF ratio from heart rate variability (HRV) of photoplethysmographic imaging (PPGI) and percentage of eyelid closure over the pupil over time (PERCLOS), and to utilize the advantages of both methods to improve the accuracy and robustness of drowsiness detection. The proposed algorithm performs three functions, including LF/HF ratio from HRV status judgment, eye state detection, and drowsiness judgment. In addition, this study utilized a near-infrared webcam to obtain a facial image to achieve non-contact measurement, alleviate the inconvenience of using a contact wearable device, and for use in a dark environment. Furthermore, we selected the appropriate RGB channel under different light sources to obtain LF/HF ratio from HRV of PPGI. The main drowsiness judgment basis of the proposed drowsiness detection system is the use of algorithm to obtain sympathetic/parasympathetic nervous balance index and percentage of eyelid closure. In the experiment, there are 10 awake samples and 30 sleepy samples. The sensitivity is 88.9%, the specificity is 93.5%, the positive predictive value is 80%, and the system accuracy is 92.5%. In addition, an electroencephalography signal was used as a contrast to validate the reliability of the proposed method.
Deep Learning Empowered Structural Health Monitoring and Damage Diagnostics for Structures with Weldment via Decoding Ultrasonic Guided Wave
Authors: Zhang Zi , Pan Hong , Wang Xingyu , Lin Zhibin
Published: July 2022

Welding is widely used in the connection of metallic structures, including welded joints in oil/gas metallic pipelines and other structures. The welding process is vulnerable to the inclusion of different types of welding defects, such as lack of penetration and undercut. These defects often initialize early-age cracking and induced corrosion. Moreover, welding-induced defects often accompany other types of mechanical damage, thereby leading to more challenges in damage detection. As such, identification of weldment defects and interaction with other mechanical damages at their early stage is crucial to ensure structural integrity and avoid potential premature failure. The current strategies of damage identification are achieved using ultrasonic guided wave approaches that rely on a change in physical parameters of propagating waves to discriminate as to whether there exist damaged states or not. However, the inherently complex nature of weldment, the complication of damages interactions, and large-scale/long span structural components integrated with structure uncertainties pose great challenges in data interpretation and making an informed decision. Artificial intelligence and machine learning have recently become emerging methods for data fusion, with great potential for structural signal processing through decoding ultrasonic guided waves. Therefore, this study aimed to employ the deep learning method, convolutional neural network (CNN), for better characterization of damage features in terms of welding defect type, severity, locations, and interaction with other damage types. The architecture of the CNN was set up to provide an effective classifier for data representation and data fusion. A total of 16 damage states were designed for training and calibrating the accuracy of the proposed method. The results revealed that the deep learning method enables effectively and automatically extracting features of ultrasonic guided waves and yielding high precise prediction for damage detection of structures with welding defects in complex situations. In addition, the effectiveness and robustness of the proposed methods for structure uncertainties using different embedding materials, and data under noise interference, was also validated and findings demonstrated that the proposed deep learning methods still exhibited a high accuracy at high noise levels.
Permutation-Based Block Code for Short Packet Communication Systems
Authors: Faure Emil , Shcherba Anatoly , Makhynko Mykola , Stupka Bohdan , Nikodem Joanna , Shevchuk Ruslan
Published: July 2022

This paper presents an approach to the construction of block error-correcting code for data transmission systems with short packets. The need for this is driven by the necessity of information interaction between objects of machine-type communication network with a dynamically changing structure and unique system of commands or alerts for each network object. The codewords of a code are permutations with a given minimum pairwise Hamming distance. The purpose of the study is to develop a statistical method for constructing a code, in contrast to known algebraic methods, and to investigate the code size. An algorithm for generating codewords has been developed. It can be implemented both by enumeration of the full set of permutations, and by enumeration of a given number of randomly selected permutations. We have experimentally determined the dependencies of the average and the maximum values of the code size on the size of a subset of permutations used for constructing the code. A technique for computing approximation quadratic polynomials for the determined code size dependencies has been developed. These polynomials and their corresponding curves estimate the size of a code generated from a subset of random permutations of such a size that a statistically significant experiment cannot be performed. The results of implementing the developed technique for constructing a code based on permutations of lengths 7 and 11 have been presented. The prediction relative error of the code size did not exceed the value of 0.72% for permutation length 11, code distance 9, random permutation subset size 50,000, and permutation statistical study range limited by 5040.
Simulation of Pressure-Driven and Channel-Based Microfluidics on Different Abstract Levels: A Case Study
Authors: Takken Michel , Wille Robert
Published: July 2022

A microfluidic device, or a Lab-on-a-Chip (LoC), performs lab operations on the microscale through the manipulation of fluids. The design and fabrication of such devices usually is a tedious process, and auxiliary tools, such as simulators, can alleviate the necessary effort for the design process. Simulations of fluids exist in various forms and can be categorized according to how well they represent the underlying physics, into so-called abstraction levels. In this work, we consider simulation approaches in 1D, which are based on analytical solutions of simplified problems, and approaches in 2D and 3D, for which we use two different Computational Fluid Dynamics (CFD) methods—namely, the Finite Volume Method (FVM) and the Lattice-Boltzmann Method (LBM). All these methods come with their pros and cons with respect to accuracy and required compute time, but unfortunately, most designers and researchers are not aware of the trade-off that can be made within the broad spectrum of available simulation approaches for microfluidics and end up choosing a simulation approach arbitrarily. We provide an overview of different simulation approaches as well as a case study of their performance to aid designers and researchers in their choice. To this end, we consider three representative use cases of pressure-driven and channel-based microfluidic devices (namely the non-Newtonian flow in a channel, the mixing of two fluids in a channel, and the behavior of droplets in channels). The considerations and evaluations raise the awareness and provide several insights for what simulation approaches can be utilized today when designing corresponding devices (and for what they cannot be utilized yet).
A Design of 10-Bit Asynchronous SAR ADC with an On-Chip Bandgap Reference Voltage Generator
Authors: Verma Deeksha , Shehzad Khuram , Kim Sung Jin , Pu Young Gun , Yoo Sang-Sun , Hwang Keum Cheol , Yang Youngoo , Lee Kang-Yoon
Published: July 2022

A proposed prototype of a 10-bit 1 MS/s single-ended asynchronous Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC) with an on-chip bandgap reference voltage generator is fabricated with 130 nm technology. To optimize the power consumption, static, and dynamic performance, several techniques have been proposed. A dual-path bootstrap switch was proposed to increase the linearity sampling. The Voltage Common Mode (VCM)-based Capacitive Digital-to-Analog Converter (CDAC) switching technique was implemented for the CDAC part to alleviate the switching energy problem of the capacitive DAC. The proposed architecture of the two-stage dynamic latch comparator provides high speed and low power consumption. Moreover, to achieve faster bit conversion with an efficient time sequence, asynchronous SAR logic with an internally generated clock is implemented, which avoids the requirement of a high-frequency external clock, as all conversions are carried out in a single clock cycle. The proposed error amplifier-based bandgap reference voltage generator provides a stable reference voltage to the ADC for practical implementation. The measurement results of the proposed SAR ADC, including an on-chip bandgap reference voltage generator, show an Effective Number of Bits (ENOB) of 9.49 bits and Signal-to-Noise and Distortion Ratio (SNDR) of 58.88 dB with 1.2 V of power supply while operating with a sampling rate of 1 MS/s.
Design, Modeling and Implementation of Digital Twins
Authors: Segovia Mariana , Garcia-Alfaro Joaquin
Published: July 2022

A Digital Twin (DT) is a set of computer-generated models that map a physical object into a virtual space. Both physical and virtual elements exchange information to monitor, simulate, predict, diagnose and control the state and behavior of the physical object within the virtual space. DTs supply a system with information and operating status, providing capabilities to create new business models. In this paper, we focus on the construction of DTs. More specifically, we focus on determining (methodologically) how to design, create and connect physical objects with their virtual counterpart. We explore the problem into several phases: from functional requirement selection and architecture planning to integration and verification of the final (digital) models. We address as well how physical components exchange real-time information with DTs, as well as experimental platforms to build DTs (including protocols and standards). We conclude with a discussion and open challenges.
A Multiwall Path-Loss Prediction Model Using 433 MHz LoRa-WAN Frequency to Characterize Foliage’s Influence in a Malaysian Palm Oil Plantation Environment
Authors: Anzum Rabeya , Habaebi Mohamed Hadi , Islam Md Rafiqul , Hakim Galang P. N. , Khandaker Mayeen Uddin , Osman Hamid , Alamri Sultan , AbdElrahim Elrashed
Published: July 2022

Palm oil is the main cash crop of tropical Asia, and the implementation of LPWAN (low-power wide-area network) technologies for smart agriculture applications in palm oil plantations will benefit the palm oil industry in terms of making more revenue. This research attempts to characterize the LoRa 433 MHz frequency channels for the available spreading factors (SF7-SF12) and bandwidths (125 kHz, 250 kHz, and 500 kHz) for wireless sensor networks. The LoRa channel modeling in terms of path-loss calculation uses empirical measurements of RSS (received signal strength) in a palm oil plantation located in Selangor, Malaysia. In this research, about 1500 LoS (line-of-sight) and 300 NLoS (non-line-of-sight) propagation measurement data are collected for path-loss prediction modeling. Using the empirical data, a prediction model is constructed. The path-loss exponent for LoS propagation of the proposed prediction model is found to be 2.34 and 2.9 for 125–250 kHz bandwidth and 500 kHz bandwidth, respectively. Again, for the NLoS propagation links, the attenuation per trunk is found to be 7.58 dB, 7.04 dB, 5.35 dB, 5.02 dB, 5.01 dB, and 5 dB for SF7-SF12, and the attenuation per canopy is found to be 9.32 dB, 7.96 dB, 6.2 dB, 5.89 dB, 5.79 dB, and 5.45 dB for SF7-SF12. Moreover, the prediction model is found to be the better choice (mean RMSE 2.74 dB) in comparison to the empirical foliage loss models (Weissberger’s and ITU-R) to predict the path loss in palm oil plantations.