bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Housing System on Anxiety, Chronic Stress, Fear, and Immune Function in Bovan Brown Laying Hens
Authors: Campbell Andrew M. , Johnson Alexa M. , Persia Michael E. , Jacobs Leonie
Published: July 2022

The scientific community needs objective measures to appropriately assess animal welfare. The study objective was to assess the impact of housing system on novel physiological and behavioral measurements of animal welfare for laying hens, including secretory and plasma Immunoglobulin (IgA; immune function), feather corticosterone (chronic stress), and attention bias testing (ABT; anxiety), in addition to the well-validated tonic immobility test (TI; fearfulness). To test this, 184 Bovan brown hens were housed in 28 conventional cages (3 birds/cage) and 4 enriched pens (25 birds/pen). Feces, blood, and feathers were collected 4 times between week 22 and 43 to quantify secretory and plasma IgA and feather corticosterone concentrations. TI tests and ABT were performed once. Hens that were from cages tended to show longer TI, had increased feather corticosterone, and decreased secretory IgA at 22 weeks of age. The caged hens fed quicker, and more hens fed during the ABT compared to the penned hens. Hens that were in conventional cages showed somewhat poorer welfare outcomes than the hens in enriched pens, as indicated by increased chronic stress, decreased immune function at 22 weeks of age but no other ages, somewhat increased fear, but reduced anxiety. Overall, these novel markers show some appropriate contrast between housing treatments and may be useful in an animal welfare assessment context for laying hens. More research is needed to confirm these findings.
Understanding and Modulating Antibody Fine Specificity: Lessons from Combinatorial Biology
Authors: Rojas Gertrudis
Published: July 2022

Combinatorial biology methods such as phage and yeast display, suitable for the generation and screening of huge numbers of protein fragments and mutated variants, have been useful when dissecting the molecular details of the interactions between antibodies and their target antigens (mainly those of protein nature). The relevance of these studies goes far beyond the mere description of binding interfaces, as the information obtained has implications for the understanding of the chemistry of antibody–antigen binding reactions and the biological effects of antibodies. Further modification of the interactions through combinatorial methods to manipulate the key properties of antibodies (affinity and fine specificity) can result in the emergence of novel research tools and optimized therapeutics.
Co-Administration of Remdesivir and Azithromycin May Protect against Intensive Care Unit Admission in COVID-19 Pneumonia Requiring Hospitalization: A Real-Life Observational Study
Authors: Ticinesi Andrea , Tuttolomondo Domenico , Nouvenne Antonio , Parise Alberto , Cerundolo Nicoletta , Prati Beatrice , Zanichelli Ilaria , Guerra Angela , Gaibazzi Nicola , Meschi Tiziana
Published: July 2022

The benefits of remdesivir treatment, with or without co-administration of antibiotics such as azithromycin, are uncertain in COVID-19 pneumonia. The aim of this retrospective single-center study was to assess the effects of remdesivir, with or without azithromycin, on hospital mortality, intensive care unit (ICU) admission, and need of non-invasive ventilation. The clinical records of the COVID-19 patients hospitalized in an Italian ward in March 2021 were analyzed, and data on comorbidities and clinical, radiological, and laboratory presentation of the disease were collected. Among 394 participants (234 M), 173 received remdesivir (43.9%), including 81 with azithromycin (20.5%). Remdesivir recipients were younger, with less comorbidities, and had better PaO2/FiO2 and clinical outcomes, including reduced mortality, but the differences were not independent of covariates. Rates of ICU transferal were 17%, 9%, and 1% in the no remdesivir, remdesivir without azithromycin, and remdesivir/azithromycin groups, respectively. In a stepwise multivariate logistic regression model, remdesivir/azithromycin co-treatment was independently associated with reduced ICU admission (vs remdesivir alone, OR 0.081, 95% CI 0.008–0.789, p = 0.031; vs no remdesivir, OR 0.060, 95% CI 0.007–0.508, p = 0.010). These data suggest that the therapeutical effect of remdesivir in COVID-19 pneumonia may be potentiated by azithromycin. The association between the two drugs should be further investigated.
A Retrospective Study of Risk Factors, Mortality, and Treatment Outcomes for Infections with Carbapenemase-Producing Enterobacterales in a Tertiary Hospital in Havana, Cuba
Authors: Yu Haiyang , Hernández González Alberto , Estévez Torres Gonzalo , González Molina María Karla , Hart Casares Marcia , Han Xu , Baldoquín Rodríguez Waldemar , Quiñones Pérez Dianelys
Published: July 2022

(1) Background: The spread of carbapenem-resistant Enterobacterales in hospitals constitutes an important epidemiological and therapeutic problem that especially affects vulnerable patients such as perioperative patients. (2) Methods: We conducted a descriptive, observational, retrospective case-control study of patients infected with carbapenemase-producing carbapenem-resistant Enterobacterales (CP-CRE) and carbapenem-susceptible Enterobacterales during the perioperative period in a tertiary hospital. (3) Results: Metallo-β-lactamase was detected in all 124 CRE isolates, with NDM-type carbapenemase being dominant, while 3 isolates coproduced KPC-type enzyme and showed high resistance rates against all antibiotics except colistin (25.2%). By analyzing the risk factors for infection, steroid use (OR: 3.22, p < 0.01), prior use of two or more antibiotics (OR: 4.04, p = 0.01), prior use of broad-spectrum cephalosporins (OR: 2.40, p = 0.04), and prior use of carbapenem (OR: 4.77, p = 0.03) were found to be independent risk factors for CP-CRE infection. In addition, in this study, we observed that the clinical outcomes of bloodstream infections and pneumonia associated with CP-CRE posed higher mortality risks. However, by analyzing the associations between treatment options and mortality, it was found that, in bloodstream infections caused by CP-CRE, colistin-based regimens showed a significant advantage (PR = 0.40, p = 0.03). (4) Conclusions: High mortality is associated with nosocomial infections in the perioperative period caused by carbapenemase-producing Enterobacterales, the dissemination of which in health care settings in Cuba remains a public health challenge.
Causative Pathogens Do Not Differ between Early, Delayed or Late Fracture-Related Infections
Authors: Corrigan Ruth A. , Sliepen Jonathan , Dudareva Maria , IJpma Frank F. A. , Govaert Geertje , Atkins Bridget L. , Rentenaar Rob , Wouthuyzen-Bakker Marjan , McNally Martin
Published: July 2022

Fracture-related infections (FRIs) are classically considered to be early (0–2 weeks), delayed (3–10 weeks) or late (>10 weeks) based on hypothesized differences in causative pathogens and biofilm formation. Treatment strategies often reflect this classification, with debridement, antimicrobial therapy and implant retention (DAIR) preferentially reserved for early FRI. This study examined pathogens isolated from FRI to confirm or refute these hypothesized differences in causative pathogens over time. Cases of FRI managed surgically at three centres between 2015–2019 and followed up for at least one year were included. Data were analysed regarding patient demographics, time from injury and pathogens isolated. Patients who underwent DAIR were also analysed separately. In total, 433 FRIs were studied, including 51 early cases (median time from injury of 2 weeks, interquartile range (IQR) of 1–2 weeks), 82 delayed cases (median time from injury of 5 weeks, IQR of 4–8 weeks) and 300 late cases (median time from injury of 112 weeks, IQR of 40–737 weeks). The type of infection was associated with time since injury; early or delayed FRI are most likely to be polymicrobial, whereas late FRIs are more likely to be culture-negative, or monomicrobial. Staphylococcus aureus was the most commonly isolated pathogen at all time points; however, we found no evidence that the type of pathogens isolated in early, delayed or late infections were different (p = 0.2). More specifically, we found no evidence for more virulent pathogens (S. aureus, Gram-negative aerobic bacilli) in early infections and less virulent pathogens (such as coagulase negative staphylococci) in late infections. In summary, decisions on FRI treatment should not assume microbiological differences related to time since injury. From a microbiological perspective, the relevance of classifying FRI by time since injury remains unclear.
In Vitro Cell Behavior and Antibiotic Activity under Sustained Release of Doxycycline-Loaded Poly(lactic-co-glycolic acid) Microspheres
Authors: Pedrini Flavia , Nazato Virgínia S. , Hausen Moema A. , Komatsu Daniel , Peña Stela S. , Almeida Ana Lídia M. , Pirola Fernanda J. C. , Françoso Marina P. , Duek Eliana A. R.
Published: July 2022

The state-of-the-art sustained drug delivery systems are related to features to improve pharmacological transport through a controlled ratio between drug release and the desired therapeutic effect. Microspheres of biodegradable polymers, such as poly(lactic-co-glycolic acid) (PLGA), play an important role in these approaches, directing the release in a specific region of interest. In this way, the encapsulation of doxycycline (DOX) as a microbial agent turns the PLGA microspheres into a potential device for the treatment of topic oral diseases. Thus, this work aimed to produce DOX-loaded PLGA microspheres and see how they interfered with mesenchymal stem cell viability and in the sustained release in antimicrobial assays. Scanning electron microscopy showed the spherical microstructured pattern, revealing assorted sized distribution, with major diameters ranging 1–3 µm. The encapsulation efficiency presented a mean of 80% in both methods to obtain the microspheres (sonication and magnetic rotation). The DOX release test revealed a gradual and continuous profile of 30–40% between 120 and 168 h. Mesenchymal stem cells cultured in PLGA with or without DOX at several concentrations revealed no effect on the cell metabolic activity. Striking morphology changes were observed by confocal microscopy after 1 to 3 days under culture. The live/dead assay indicated that when microsphere densities were increased (from 10 to 100 µg/mL) cultured cells presented an internalized pattern of microspheres in both groups of PLGA containing DOX or not, while slight cell death signals were identified nearby microsphere clusters. Microbiological assays performed by the agar diffusion test pointed out that an inhibition zone was identified in Staphylococcus aureus (S. aureus) cultures at earlier times of DOX release. Despite the well-known use of PLGA as a drug delivery vehicle, when synthesized with DOX, it presents both characteristics of the desired treatment to prevent healthy tissue damage while avoiding bacterial growth in a microenvironment with anatomical features, such as grooves, projections, and other tough conditions that favor the development of oral diseases.
How Aging and Oxidative Stress Influence the Cytopathic and Inflammatory Effects of SARS-CoV-2 Infection: The Role of Cellular Glutathione and Cysteine Metabolism
Authors: Galli Francesco , Marcantonini Giada , Giustarini Daniela , Albertini Maria Cristina , Migni Anna , Zatini Linda , Gioiello Antimo , Rossi Ranieri , Bartolini Desirée
Published: July 2022

SARS-CoV-2 infection can cause a severe respiratory distress syndrome with inflammatory and thrombotic complications, the severity of which increases with patients’ age and presence of comorbidity. The reasons for an age-dependent increase in the risk of severe COVID-19 could be many. These include defects in the homeostatic processes that control the cellular redox and its pivotal role in sustaining the immuno-inflammatory response to the host and the protection against oxidative stress and tissue degeneration. Pathogens may take advantage of such age-dependent abnormalities. Alterations of the thiol redox balance in the lung tissue and lining fluids may influence the risk of infection, and the host capability to respond to pathogens and to avoid severe complications. SARS-CoV-2, likewise other viruses, such as HIV, influenza, and HSV, benefits in its replication cycle of pro-oxidant conditions that the same viral infection seems to induce in the host cell with mechanisms that remain poorly understood. We recently demonstrated that the pro-oxidant effects of SARS-CoV-2 infection are associated with changes in the cellular metabolism and transmembrane fluxes of Cys and GSH. These appear to be the consequence of an increased use of Cys in viral protein synthesis and to ER stress pathway activation that interfere with transcription factors, as Nrf2 and NFkB, important to coordinate the metabolism of GSH with other aspects of the stress response and with the pro-inflammatory effects of this virus in the host cell. This narrative review article describes these cellular and molecular aspects of SARS-CoV-2 infection, and the role that antivirals and cytoprotective agents such as N-acetyl cysteine may have to limit the cytopathic effects of this virus and to recover tissue homeostasis after infection.
Evaluation of Proanthocyanidins from Kiwi Leaves (Actinidia chinensis) against Caco-2 Cells Oxidative Stress through Nrf2-ARE Signaling Pathway
Authors: Lv Ji-Min , Gouda Mostafa , Ye Xing-Qian , Shao Zhi-Peng , Chen Jian-Chu
Published: July 2022

Proanthocyanidins (PAs) are considered to be effective natural byproduct and bioactive antioxidants. However, few studies have focused on their mode of action pathways. In this study, reactive oxygen species (ROS), oxidative stress indices, real-time PCR, Western blotting, confocal microscopy, and molecular docking were used to investigate the protective effect of purified kiwi leaves PAs (PKLPs) on Caco-2 cells’ oxidative stress mechanisms. The results confirmed that pre-treatment with PKLPs significantly reduced H2O2-induced oxidative damage, accompanied by declining ROS levels and malondialdehyde (MDA) accumulation in the Caco-2 cells. The PKLPs upregulated the expression of antioxidative enzymes (GSH-px, CAT, T-SOD) and the relative mRNA (Nrf, HO-1, SOD-1, CAT) of the nuclear factor erythroid 2-related factor (Nrf2) signaling pathway. The protein-expressing level of the Nrf2 and its relative protein (NQO-1, HO-1, SOD-1) were significantly increased (p < 0.05) in the PKLPs pre-treatment group compared to the model group. In conclusion, the novelty of this study is that it explains how PKLPs’ efficacy on the Nrf2-ARE signaling pathway, in protecting vital cells from oxidative stress, could be used for cleaner production.
What Are the Oxidizing Intermediates in the Fenton and Fenton-like Reactions? A Perspective
Authors: Meyerstein Dan
Published: July 2022

The Fenton and Fenton-like reactions are of major importance due to their role as a source of oxidative stress in all living systems and due to their use in advanced oxidation technologies. For many years, there has been a debate whether the reaction of FeII(H2O)62+ with H2O2 yields OH• radicals or FeIV=Oaq. It is now known that this reaction proceeds via the formation of the intermediate complex (H2O)5FeII(O2H)+/(H2O)5FeII(O2H2)2+ that decomposes to form either OH• radicals or FeIV=Oaq, depending on the pH of the medium. The intermediate complex might also directly oxidize a substrate present in the medium. In the presence of FeIIIaq, the complex FeIII(OOH)aq is formed. This complex reacts via FeII(H2O)62+ + FeIII(OOH)aq → FeIV=Oaq + FeIIIaq. In the presence of ligands, the process often observed is Ln(H2O)5−nFeII(O2H) → L•+ + Ln−1FeIIIaq. Thus, in the presence of small concentrations of HCO3− i.e., in biological systems and in advanced oxidation processes—the oxidizing radical formed is CO3•−. It is evident that, in the presence of other transition metal complexes and/or other ligands, other radicals might be formed. In complexes of the type Ln(H2O)5−nMIII/II(O2H−), the peroxide might oxidize the ligand L without oxidizing the central cation M. OH• radicals are evidently not often formed in Fenton or Fenton-like reactions.
Hydrogen Sulfide Regulates Irisin and Glucose Metabolism in Myotubes and Muscle of HFD-Fed Diabetic Mice
Authors: Parsanathan Rajesh , Jain Sushil K.
Published: July 2022

Irisin, a novel myokine, is secreted by the muscle following proteolytic cleavage of fibronectin type III domain containing 5 (FNDC5) and is considered a novel regulator of glucose homeostasis. Cystathionine γ-lyase (CSE) produces hydrogen sulfide (H2S) and is involved in glucose homeostasis. We examined the hypothesis that H2S deficiency leads to decreased FNDC5 and irisin secretion, and thereby alters glucose metabolism. High-fat diet-fed mice exhibited elevated blood glucose and significantly reduced levels of CSE, H2S, and PGC-1α, with decreased FNDC5/irisin levels and increased oxidative stress in the muscle compared with those of normal diet-fed mice (control). High glucose or palmitate decreases CSE/PGC-1α/FNDC5 levels and glucose uptake in myotubes. Inhibitors (propargylglycine and aminooxyacetate) of H2S producing enzymes or CSE siRNA significantly decreased levels of H2S and FNDC5 along with PGC-1α; similar H2S-deficient conditions also resulted in decreased GLUT4 and glucose uptake. The levels of H2S, PGC-1α, and FNDC5 and glucose uptake were significantly upregulated after treatment with l-cysteine or an H2S donor. Myoblast differentiation showed upregulation of PGC-1α and FNDC5, which was consistent with the increased expression of CSE/H2S. These findings suggest that the upregulation of H2S levels can have beneficial effects on glucose homeostasis via activation of the PGC-1α/FNDC5/irisin signaling pathway.
Relevance of Diabetic Retinopathy with AGEs and Carotenoid Levels Assessed by Skin Sensors
Authors: Sasaki Junichi , Takayanagi Yuji , Kadoh Yoichi , Tanito Masaki
Published: July 2022

Advanced glycation end products (AGEs) and carotenoids, the major prooxidants and antioxidants in vivo, respectively, are thought to be associated with diabetes mellitus (DM). To estimate AGEs and carotenoid levels simultaneously in patients with DM, we used noninvasive fingertip skin sensors. The study population included 249 eyes of 249 Japanese subjects (130 men, 119 women; mean age ± standard deviation, 69.9 ± 12.0 years). Ninety-three patients had DM, which included diabetic retinopathy (DR) (n = 44) and no DR (NDR) (n = 49), and 156 controls. Compared to the controls (0.44 ± 0.07 arbitrary unit (A.U.)), the AGEs scores were significantly higher in DM (0.47 ± 0.09, p = 0.029) and DR (0.49 ± 0.08, p = 0.0006) patients; no difference was seen between NDR (0.45 ± 0.09, p = 0.83) and controls. Multivariate analyses indicated that a higher AGEs level is a risk factor for DR (r = 0.030, p = 0.0025). However, the carotenoid scores did not differ in any comparisons between the controls (327.7 ± 137.0 O.D.) and patients with DM (324.7 ± 126.4, p = 0.86), NDR (320.4 ± 123.6, p = 0.93), or DR (329.4 ± 130.8, p = 0.93). The carotenoid scores correlated negatively with the AGEs scores (r = −0.21, p = 0.0007), and reflected the Veggie intake score (p < 0.0001). In patients with DM, estimations of AGEs and carotenoid levels using skin sensors can be useful for assessing their risk of DR and vegetable intake, respectively.
Recent Application of Dijkstra’s Algorithm in the Process of Production Planning
Authors: Behún Marcel , Knežo Dušan , Cehlár Michal , Knapčíková Lucia , Behúnová Annamária
Published: July 2022

This paper aims to develop a method that could serve as a tool for evaluating extracted raw materials in terms of use by considering the place of extraction and consumption. Dijkstra´s algorithm solves many of the shortest path problems observed in the production planning of raw materials. The algorithm requires knowledge of the relative distance between the vertices and the definition of the Euclidean distance of the vertices from the target vertex. The algorithm scans all of the paths and chooses the one with the minimum distance. At the same time, it would be able to identify the places of sale of raw materials and transport sites for the transportation of raw materials. It would have a database of point and line sources of occurrence (mining, deposit), places of transport (transmission network), and points of sale (seller). At present, geo-statistics is becoming an essential tool for solving various problems in modern deposit geology. Its results are used to calculate reserves and the economic valuation of the deposit. In the process of production planning, it is necessary to constantly process and analyze the geological information obtained during the mining survey.
Intelligent Black–Litterman Portfolio Optimization Using a Decomposition-Based Multi-Objective DIRECT Algorithm
Authors: Li Chen , Chen Yidong , Yang Xueying , Wang Zitian , Lu Zhonghua , Chi Xuebin
Published: July 2022

It is agreed that portfolio optimization is of great importance for the financial market. However, input sensitivity and highly-concentrated portfolios have posed a challenge. In this paper, a random forest-based Black–Litterman model is developed, aiming to further enhance the portfolio performance, which adopts a novel method for generating investor views on the basis of random forests. More specifically, the view vector is generated based on the predicted asset returns obtained by random forests, and the confidence matrix which contains the uncertainty of each view is measured by the difference in the predicted values of multiple trees. Furthermore, motivated by decomposition strategy, a novel multi-objective DIRECT algorithm is introduced to effectively resolve the proposed model. Through the construction of a unique indicator, the algorithm possesses the capacity to select potentially-optimal hyperrectangles in all reference directions simultaneously, which will further improve the exploratory nature. Experimental results have demonstrated that the proposed algorithm achieves a better performance over NSGA-II and MOEA/D on the MOP and DTLZ benchmark problems. It is also experimentally verified that the random forest-based Black–Litterman model can obtain higher cumulative returns and Sharpe ratios in the application of Chinese stock markets when compared to the classic MV model.
Development of a Multi-Sensor Concept for Real-Time Temperature Measurement at the Cutting Insert of a Single-Lip Deep Hole Drilling Tool
Authors: Ramme Johannes , Wegert Robert , Guski Vinzenz , Schmauder Siegfried , Moehring Hans-Christian
Published: July 2022

The mechanical energy resulting from cutting processes is turned almost completely in thermal energy, which encourages thermal procedures, such as diffusion, leading to higher wear in the cutting tool and thus to higher temperatures. Furthermore, high temperatures influence the properties of the marginal zones in the workpiece. In this presented work, the in-process temperature of a cutting insert during single-lip deep hole drilling (SLD) is investigated. Therefore, a sensor-integrated tool with resistance temperature detectors (RTD) placed beneath the cutting insert is developed. First, the thermal properties of the cutting insert are adjusted to fit the assembled tool. Afterwards, a CEL-Simulation is obtained to examine the temperature distribution at the cutting edge of the SLD-tool. The temperatures calculated by simulation can be compared to the in-process temperatures of the sensor integrated tool. Because of the usage of a cooling lubricant, simulated temperatures can be varied with a factor to fit the experimentally measured temperature curves. The highest temperature during the process appears at the outer edge of the cutting insert. By knowing the thermal properties, the maximum process temperatures for the deep hole drilling operation are to be calculated. The results represent a contribution to an interdisciplinary research project “Surface Conditioning in Machining Processes” (SPP 2086) of the German Research Foundation (DFG).
Magic of 5G Technology and Optimization Methods Applied to Biomedical Devices: A Survey
Authors: Kouhalvandi Lida , Matekovits Ladislau , Peter Ildiko
Published: July 2022

Wireless networks have gained significant attention and importance in healthcare as various medical devices such as mobile devices, sensors, and remote monitoring equipment must be connected to communication networks. In order to provide advanced medical treatments to patients, high-performance technologies such as the emerging fifth generation/sixth generation (5G/6G) are required for transferring data to and from medical devices and in addition to their major components developed with improved optimization methods which are substantially needed and embedded in them. Providing intelligent system design is a challenging task in medical applications, as it affects the whole behaviors of medical devices. A critical review of the medical devices and the various optimization methods employed are presented in this paper, to pave the way for designers to develop an apparatus that is applicable in the healthcare industry under 5G technology and future 6G wireless networks.
Improving the Quality of Laser-Welded Butt Joints of Metal–Polymer Sandwich Composites
Authors: Murzin Serguei P. , Palkowski Heinz , Melnikov Alexey A. , Blokhin Maksim V. , Osipov Stanislav
Published: July 2022

Sandwich panels are promising composite materials, although the possibilities for their thermal joining are limited due to the degradation of the polymer core at elevated temperatures. The purpose of this study is to improve the quality of the butt joints in metal–polymer sandwich composites performed by laser welding. A pulsed Nd:YAG Rofin StarWeld Performance laser was used to perform the two-sided welding of the metal–polymer three-layer composite material. On each of the two sides of the material, a welded joint was made with partial penetration of the covering steel sheets, which was considered a prerequisite for preventing the degradation of the core polymer layer. The energy density of the laser irradiation was redistributed by increasing the diameter of the laser spot. The structure of the welded joints was examined using a polarized optical microscope and a scanning electron microscope. It was determined that the laser treatment resulted in a partial penetration weld on each of the two covering metal sheets of the material, reaching a depth of more than 50% of the sheet’s thickness without damaging the polymer. The welding area consisted of two zones, one being the weld metal and the other the heat-affected zone. As a result of relatively rapid heating and cooling cycles, fine-dispersed structures were formed in the heat-affected and remelted zones. The performed tensile tests showed that the strength of the welded area was about 80% of that of the base material.
Predicting Rock Brittleness Using a Robust Evolutionary Programming Paradigm and Regression-Based Feature Selection Model
Authors: Jamei Mehdi , Mohammed Ahmed Salih , Ahmadianfar Iman , Sabri Mohanad Muayad Sabri , Karbasi Masoud , Hasanipanah Mahdi
Published: July 2022

Brittleness plays an important role in assessing the stability of the surrounding rock mass in deep underground projects. To this end, the present study deals with developing a robust evolutionary programming paradigm known as linear genetic programming (LGP) for estimating the brittleness index (BI). In addition, the bootstrap aggregate (Bagged) regression tree (BRT) and two efficient lazy machine learning approaches, namely local weighted linear regression (LWLR) and KStar approach, were examined to validate the LGP model. To the best of our knowledge, this is the first attempt to estimate the BI through the LGP model. A tunneling project in Pahang state, Malaysia, was investigated, and the requirement datasets were measured to construct the proposed models. According to the results from the testing phase, the LGP model yielded the best statistical indicators (R = 0.9529, RMSE = 0.4838, and IA = 0.9744) for modeling BI, followed by LWLR (R = 0.9490, RMSE = 0.6607, and IA = 0.9400), BRT (R = 0.9433, RMSE = 0.6875, and IA = 0.9324), and KStar (R = 0.9310, RMSE = 0.7933, and IA = 0.9095), respectively. In addition, the sensitivity analysis demonstrated that the dry density factor demonstrated the most effective prediction of BI.
Detection of Polystyrene Microplastic Particles in Water Using Surface-Functionalized Terahertz Microfluidic Metamaterials
Authors: Park Sae June , Ahn Yeong Hwan
Published: July 2022

We propose a novel method for detecting microplastic particles in water using terahertz metamaterials. Fluidic channels are employed to flow the water, containing polystyrene spheres, on the surface of the metamaterials. Polystyrene spheres are captured only near the gap structure of the metamaterials as the gap areas are functionalized. The resonant frequency of terahertz metamaterials increased while we circulated the microplastic solution, as polystyrene spheres in the solution are attached to the metamaterial gap areas, which saturates at a specific frequency as the gap areas are filled by the polystyrene spheres. Experimental results were revisited and supported by finite-difference time-domain simulations. We investigated how this method can be used for the detection of microplastics with various solution densities. The saturation time of the resonant frequency shift was found to decrease, while the saturated resonant frequency shift increased as the solution density increased.
Towards Resolving Challenges Associated with Climate Change Modelling in Africa
Authors: Oluwagbemi Olugbenga Oluseun , Hamutoko Josefina Tulimevava , Fotso-Nguemo Thierry Christian , Lokonon Boris Odilon Kounagbe , Emebo Onyeka , Kirsten Kelly Louise
Published: July 2022

Climate change is a significant concern impacting food security, agricultural reform, disease transmission, and disruption to human, plant, and animal ecosystems, along with a host of additional consequences, ultimately affecting the quality of life and the livelihoods of the global population. African-based research aims to better understand the impact of climate change on nature and on different aspects of humanity, as well as improve forecasting for greater economic potential. However, researchers often encounter various challenges and obstacles. Here, we conducted a bibliographic analysis and interpretation of relevant climate change peer-reviewed research articles related to the African continent. From this analysis, challenges associated with climate change modelling in Africa were identified. Primarily, the lack of an extensive observational network and technological limitations hinder modelling efforts. Additionally, an apparent pull of scientists away from African institutions to institutions further afield was observed. Novel solutions to these challenges are proffered. Finally, we highlight how the German Deutscher Akademischer Austauschdienst (DAAD) Climate Research for Alumni and Postdocs in Africa (climapAfrica) program is contributing towards resolving these challenges.
Research on Geometric Design Standards for Freeways under a Fully Autonomous Driving Environment
Authors: Zhao Yifei , Ying Xinzhi , Li Jingru
Published: July 2022

The formulation of the current geometric design standard for freeways considers the influence of the “human-vehicles-road-environment” system. In the fully autonomous environment, the driver has been liberated from the system, which means that the influence of “human” will be reduced. The requirements or limitations of the freeway geometric design standard, which consider the driver’s psychological and physical factors in the traditional driving environment, can be more flexible in the fully automatic driving environment. By using the methods of comparative analysis, theoretical analysis, and theoretical calculation, this article researches the geometric design standard for freeways in an autonomous driving environment from four aspects: control elements of geometric design, horizontal alignment, vertical alignment, and cross-section elements. The main contribution of this article is to propose the recommended values of the geometric design standard for freeways in a fully autonomous driving environment, which can provide reference for the formulation of relevant standards or specifications for autonomous driving roads in the future.
Clustered and Distributed Caching Methods for F-RAN-Based mmWave Communications
Authors: Aldalbahi Adel , Jasim Mohammed A. , Siasi Nazli , Bouzguenda Mounir , Enshasy Hesham , Sumsudeen Rajamohamed
Published: July 2022

Fog-radio access networks (F-RANs) alleviate fronthaul delays for cellular networks as compared to their cloud counterparts. This allows them to be suitable solutions for networks that demand low propagation delays. Namely, they are suitable for millimeter wave (mmWave) operations that suffer from short propagation distances and possess a poor scattering environment (low channel ranks). The F-RAN here is comprised of fog nodes that are collocated with radio remote heads (RRHs) to provide local processing capabilities for mobile station (MS) terminals. These terminals demand various network functions (NFs) that correspond to different service requests. Now, provisioning these NFs on the fog nodes also yields service delays due to the requirement for service migration from the cloud, i.e., offloading to the fog nodes. One solution to reduce this service delay is to provide cached copies of popular NFs in advance. Hence, it is critical to study function popularity and allow for content caching at the F-RAN. This is further a necessity given the limited resources at the fog nodes, thus requiring efficient resource management to enhance network capacity at reduced power and cost penalty. This paper proposes novel solutions that allocate popular NFs on the fog nodes to accelerate services for the terminals, namely, the clustered and distributed caching methods. The two methods are analyzed and compared against the baseline uncached provisioning schemes in terms of service delay, energy consumption, and cost.
In-Motion Coarse Alignment Method Based on Position Loci and Optimal-REQUEST for SINS
Authors: Huang Haoqian , Wei Jiaying
Published: July 2022

In this paper, an improved in-motion coarse alignment method is proposed for a strapdown inertial navigation system (SINS) using position loci obtained from the Global Positioning System (GPS). The difference from the popular coarse alignment methods is that the proposed algorithm uses GPS position loci information to form the vector observation, and does not need velocity information, which expands the application range of in-motion coarse alignment. In addition, this paper utilizes the Optimal-REQUEST algorithm to reduce the influence of random errors contained in the vector observation. The Optimal-REQUEST algorithm is an adaptive iterative updating algorithm, which can adaptively adjust the gain of the filter according to the loss function. Simulation results confirmed that the proposed algorithm can suppress the impact of random errors effectively. The pitch, roll and yaw angles calculated by the proposed algorithm were improved by 51.95%, 53.80% and 63.03% compared with the comparison algorithms.
Overcoming Metabolic Constraints in the MEP-Pathway Enrich Salvia sclarea Hairy Roots in Therapeutic Abietane Diterpenes
Authors: Alfieri Mariaevelina , Ambrosone Alfredo , Vaccaro Mariacarmela , De Tommasi Nunziatina , Leone Antonietta
Published: July 2022

Abietane diterpenoids (e.g., carnosic acid, aethiopinone, 1-oxoaethiopinone, salvipisone, and ferruginol) synthesized in the roots of several Salvia species have proved to have promising biological activities, but their use on a large scale is limited by the very low content extracted from in vivo roots. In this review, we summarized our efforts and the achieved results aimed at optimizing the synthesis of these diterpenes in Salvia sclarea hairy roots by either elicitation or by modifying the expression of genes encoding enzymes of the MEP-pathway, the biosynthetic route from which they derive. Stable S. sclarea hairy roots (HRs) were treated with methyl jasmonate or coronatine, or genetically engineered, by tuning the expression of genes controlling enzymatic rate-limiting steps (DXS, DXR, GGPPS, CPPS alone or in combination), by silencing of the Ent-CPPS gene, encoding an enzyme acting at gibberellin lateral competitive route or by coordinate up-regulation of biosynthetic genes mediated by transcription factors (WRKY and MYC2). Altogether, these different approaches successfully increased the amount of abietane diterpenes in S. sclarea HRs from to 2 to 30 times over the content found in the control HR line.
Hosted Cuckoo Optimization Algorithm with Stacked Autoencoder-Enabled Sarcasm Detection in Online Social Networks
Authors: Elkamchouchi Dalia H. , Alzahrani Jaber S. , Asiri Mashael M. , Al Duhayyim Mesfer , Mohsen Heba , Motwakel Abdelwahed , Zamani Abu Sarwar , Yaseen Ishfaq
Published: July 2022

Sarcasm detection has received considerable interest in online social media networks due to the dramatic expansion in Internet usage. Sarcasm is a linguistic expression of dislikes or negative emotions by using overstated language constructs. Recently, detecting sarcastic posts on social networking platforms has gained popularity, especially since sarcastic comments in the form of tweets typically involve positive words that describe undesirable or negative characteristics. Simultaneously, the emergence of machine learning (ML) algorithms has made it easier to design efficacious sarcasm detection techniques. This study introduces a new Hosted Cuckoo Optimization Algorithm with Stacked Autoencoder-Enabled Sarcasm Detection and Classification (HCOA-SACDC) model. The presented HCOA-SACDC model predominantly focuses on the detection and classification of sarcasm in the OSN environment. To achieve this, the HCOA-SACDC model pre-processes input data to make them compatible for further processing. Furthermore, the term frequency-inverse document frequency (TF-IDF) model is employed for the useful extraction of features. Moreover, the stacked autoencoder (SAE) model is utilized for the recognition and categorization of sarcasm. Since the parameters related to the SAE model considerably affect the overall classification performance, the HCO algorithm is exploited to fine-tune the parameters involved in the SAE, showing the novelty of the work. A comprehensive experimental analysis of a benchmark dataset is performed to highlight the superior outcomes of the HCOA-SACDC model. The simulation results indicate that the HCOA-SACDC model accomplished enhanced performance over other techniques.
Towards a Multi-Perspective Time of Flight Laser Ranging Device Based on Mirrors and Prisms
Authors: Pogačnik Luka , Munih Marko
Published: July 2022

This paper investigates the feasibility of redirecting the field of view (FOV) of a light-based time-of-flight (ToF) ranging device, commonly known as a pulsed lidar, using fixed mirrors and prisms for possible future use in robotics. The emphasis is on configurations where the FOV redirection element is positioned beyond the ranging device’s dead zone. A custom made direct ToF ranging device with time-over-threshold (TOT)-based walk error compensation was used to evaluate the effects of the FOV redirecting optics on range measurement accuracy and precision. The tests include redirecting the FOV with a clean prism with anti-reflective (AR) coating on its legs, as well as with a regular and a first surface mirror in both a clean and dusted state. The study finds the prism to be unsuitable due to parasitic reflections, which ruin the ranging data. The clean mirrors were found to have no noticeable effect on ranging accuracy. When they are dusty, mirrors introduce a negative measurement error. This effect is the most pronounced when a mirror is positioned toward the end of the partial dead zone of the ToF rangefinder, but loses influence as the mirror is moved farther away. The error is attributed to the parasitic reflection off dust on the mirror, which reduces the time of detection of the pulse reflected off the real target, and interferes with the walk error compensation by widening the detected pulse.
Automatic Classification of Pollen Grain Microscope Images Using a Multi-Scale Classifier with SRGAN Deblurring
Authors: Chen Xingyu , Ju Fujiao
Published: July 2022

Pollen allergies are seasonal epidemic diseases that are accompanied by high incidence rates, especially in Beijing, China. With the development of deep learning, key progress has been made in the task of automatic pollen grain classification, which could replace the time-consuming and laborious manual identification process using a microscope. In China, few pioneering works have made significant progress in automatic pollen grain classification. Therefore, we first constructed a multi-class and large-scale pollen grain dataset for the Beijing area in preparation for the task of pollen classification. Then, a deblurring pipeline was designed to enhance the quality of the pollen grain images selectively. Moreover, as pollen grains vary greatly in size and shape, we proposed an easy-to-implement and efficient multi-scale deep learning architecture. Our experimental results showed that our architecture achieved a 97.7% accuracy, based on the Resnet-50 backbone network, which proved that the proposed method could be applied successfully to the automatic identification of pollen grains in Beijing.
An Adaptive Multiobjective Genetic Algorithm with Multi-Strategy Fusion for Resource Allocation in Elastic Multi-Core Fiber Networks
Authors: Xu Zhanqi , Xu Qian , Lv Jianxin , Ma Tao , Chen Tingting
Published: July 2022

Core switching on different links in optical networks enables network operators to allocate network resources more flexibly, so as to reduce the network request blocking ratio under limited resources. Facing a differentiated network environment and diversified user demands, network operators need to optimize multiple objectives that are independent and diversionary of each other, and to provide multiple resource allocation schemes whose objective values do not dominate each other. For the static routing, spectrum, and core assignment (RSCA) problem in elastic optical networks with multi-core fiber (MCF-EONs), there is no literature that simultaneously considers core switching and multiobjective optimization algorithms. This paper improves the existing models and algorithms to adapt to the RSCA problem. In this paper, the RSCA problem is formulated as an integer linear programming model to minimize both network request blocking and crosstalk ratios simultaneously by considering core switching and inter-core crosstalk. To solve the model efficiently, we, therefore, design a joint routing and core coding scheme supporting core switching and propose a multiobjective evolutionary algorithm based on decomposition with adaptation and multi-strategy fusion (MOEA/D-AMSF), which integrates the new mechanisms of hybrid initial population generation, adaptive crossover, and double-layer and multi-point mutation in different iteration stages. These new mechanisms accelerate algorithm convergence and enhance solution diversity. Simulation results show that the proposed algorithm can obtain more dominated and diverse solutions compared with the existing multiobjective algorithm without considering core switching.
Experimental Study on the Space Electrostatic Discharge Effect and the Single Event Effect of SRAM Devices for Satellites
Authors: Wang Xuan , Chen Rui , Yuan Runjie , Chen Qian , Liang Yanan , Han Jianwei
Published: July 2022

Space Electrostatic Discharge Effect (SESD) and Single Event Effect (SEE) are two major space environmental factors that cause spacecraft failure. Previous studies have established that both can lead to soft errors such as upset of memory cells. An ESD generator and a pulsed laser experimental facility were used to test a low-power asynchronous timing monolithic SRAM. The characteristics of soft error number, single/multi-bit upsets, and supply current values were compared for similarities and differences. The test revealed that SEE-induced soft errors were mainly single-bit upsets (SBU), whereas SESD-induced soft errors were predominantly multi-bit upsets (MBU). Additionally, when soft errors occur in the circuits, the current of the power supply drops, which enables the device to be evaluated by monitoring the current value. This study provides experimental support for distinguishing device errors caused by these two effects, as well as references for further accurate identification of in-orbit faults and corresponding protection design.
Structure of Atmospheric Turbulence
Authors: Shikhovtsev Artem Yurievich , Kopylov Evgeniy Anatolevich
Published: July 2022

Turbulence is a phenomenon observed in the motions of fluids and gases [...]
Effect of Pore Structure on CO2 Adsorption Performance for ZnCl2/FeCl3/H2O(g) Co-Activated Walnut Shell-Based Biochar
Authors: Guo Tuo , Tian Wengang , Wang Yanxia
Published: July 2022

Walnut shell is a very potential biochar precursor because of its wide source, low cost, and easy structure modification. In this paper, the co-activation method of FeCl3, ZnCl2 and H2O(g) was adopted to prepare walnut shell-based biochar with high microporosity and the effect of pore structure on CO2 adsorption performance at different temperatures was investigated. The prepared biochar had a larger specific surface area (2647.8 m2 g−1), satisfactory micropore area (2008.7 m2 g−1) and high total pore volume (2.58 cm3 g−1). At 273 K and 298 K, its CO2 adsorption capacity was 4.79 mmol g−1 and 3.20 mmol g−1, respectively. Particularly, CO2 adsorbed uptake on biochar was strongly sensitive to their narrow micropore volume, instead of the total specific surface area, total pore volume, and micropore specific surface area. The optimal pore size beneficial for CO2 adsorption was 0.33–0.82 nm at 273 K, but the optimal pore size was 0.33–0.39 nm at 298 K. It provides theoretical guidance for future material preparation and selection, and FeCl3, ZnCl2 and H2O(g) may be effective biochar activators.
Lightning Cessation Guidance Using Polarimetric Radar Data and Lightning Mapping Array in the Washington, D.C. Area
Authors: Drugan John J. , Preston Ari D.
Published: July 2022

Polarimetric radar data and total lightning data are used to develop lightning cessation guidance for isolated cells in the Washington, D.C. area. A total of 23 non-severe thunderstorms during the 2015–2017 warm seasons are analyzed. Radar and lightning data are superimposed using the Warning Decision Support System–Integrated Information software to develop cessation algorithms. This includes using the hydrometeor classification algorithm to locate graupel for each convective cell. Results show that the three best-performing cessation algorithms use thresholds of (1) ZH ≥ 40 dBZ at −5 °C, (2) ZH ≥ 35 dBZ at −10 °C, and (3) graupel at −15 °C. Lightning is not expected 15 min after the threshold is no longer met for each algorithm. These algorithms are recommended only for isolated cells in the Washington, D.C. area. Further study needs to be completed to draw conclusions for other convective cell types and different geographic regions.