bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Antisolvent Precipitation Method for Formulating Excipient-Free Nanoparticles of Psychotropic Drugs
Authors: Wu Carina Yeeka , Wang Wei
Published: April 2022

The aim of the present study was to systematically examine the effects of variations in the process parameters of the antisolvent precipitation method employed in the preparation of excipient-free pure nanoparticles of five existing/potential psychotropic drugs, namely amitriptyline hydrochloride (AMI), coumarin 6 (COU), curcumin (CUR), nortriptyline hydrochloride (NOR), and prochlorperazine dimaleate (PRO). In the preparation protocols employed, AMI and NOR were expected to be charged enough to be identified as surface-active molecules. Through the employment of five different preparation protocols, the effects of varying the flow rate, the compound concentration in the solvent solution C0solvent, the solvent:antisolvent ratio (SAS-ratio), and pH of the antisolvent on the final size of the particles DHf were investigated in detail and the results were explained using available theories for the antisolvent precipitation method. We found that DHf increased with the average of the octanol-water partition coefficients (logP)av of the compound. Moreover, the average of the final particle sizes (DHf)av increased linearly with (logP)av. These findings are useful for predicting the size of nanodrugs prepared through the antisolvent precipitation method.
A Comprehensive Review of Patented Technologies to Fabricate Orodispersible Films: Proof of Patent Analysis (2000–2020)
Authors: Gupta Maram , Gowda Devegowda , Kumar Tegginamath , Rosenholm Jessica
Published: April 2022

Orodispersible films (ODFs)are ultra-thin, stamp-sized, rapidly disintegrating, and attractive oral drug delivery dosage forms best suited for the pediatric and geriatric patient populations. They can be fabricated by different techniques, but the most popular, simple, and industrially applicable technique is the solvent casting method (SCM). In addition, they can also be fabricated by extrusion, printing, electrospinning, and by a combination of these technologies (e.g., SCM + printing). The present review is aimed to provide a comprehensive overview of patented technologies of the last two decades to fabricate ODFs. Through this review, we present evidence to adamantly confirm that SCM is the most popular method while electrospinning is the most recent and upcoming method to fabricate ODFs. We also speculate around the more patent-protected technologies especially in the domain of printing (two or three-dimensional), extrusion (ram or hot-melt extrusion), and electrospinning, or a combination of the methods thereof.
Deep Eutectic Solvent Formulations and Alginate-Based Hydrogels as a New Partnership for the Transdermal Administration of Anti-Inflammatory Drugs
Authors: Pedro Sónia N. , Mendes Maria S. M. , Neves Bruno M. , Almeida Isabel Filipa , Costa Paulo , Correia-Sá Inês , Vilela Carla , Freire Mara G. , Silvestre Armando J. D. , Freire Carmen S. R.
Published: April 2022

The transdermal administration of nonsteroidal anti-inflammatory drugs (NSAIDs) is a valuable and safer alternative to their oral intake. However, most of these drugs display low water solubility, which makes their incorporation into hydrophilic biopolymeric drug-delivery systems difficult. To overcome this drawback, aqueous solutions of bio-based deep eutectic solvents (DES) were investigated to enhance the solubility of ibuprofen, a widely used NSAID, leading to an increase in its solubility of up to 7917-fold when compared to its water solubility. These DES solutions were shown to be non-toxic to macrophages with cell viabilities of 97.4% (at ibuprofen concentrations of 0.25 mM), while preserving the anti-inflammatory action of the drug. Their incorporation into alginate-based hydrogels resulted in materials with a regular structure and higher flexibility. These hydrogels present a sustained release of the drug, which is able, when containing the DES aqueous solution comprising ibuprofen, to deliver 93.5% of the drug after 8 h in PBS. Furthermore, these hydrogels were able to improve the drug permeation across human skin by 8.5-fold in comparison with the hydrogel counterpart containing only ibuprofen. This work highlights the possibility to remarkably improve the transdermal administration of NSAIDs by combining new drug formulations based on DES and biopolymeric drug delivery systems.
Collapse Dynamics of Vortex Beams in a Kerr Medium with Refractive Index Modulation and PT-Symmetric Lattices
Authors: Yao Gang , Li Yuhua , Chen Rui-Pin
Published: April 2022

Using the two-dimensional nonlinear Schrödinger equation, the collapse dynamics of vortex beams in a Kerr medium with refractive index modulation and parity–time (PT) symmetric lattices are explored. The critical power for the collapse of vortex beams in a Kerr medium with real optical lattices (i.e., refractive index modulation lattices) was obtained and discussed. Numerical calculations showed that the number of self-focusing points, the locations of the collapse, and the propagation distances for collapse are sensitively dependent on the modulation factors, topological charge numbers, and initial powers. When the vortex optical field propagates in a Kerr medium with real optical lattices, the optical field will collapse into a symmetrical shape. However, the shape of the vortex beam will be chaotically distorted and collapse in asymmetric patterns during propagation in a Kerr medium with PT-symmetric lattices because of the presence of the complex refraction index. Introducing PT-symmetric lattices into nonlinear Kerr materials may offer a new approach to controlling the collapse of vortex beams.
Radiographic Imaging as a Quality Index Proxy for Brachiaria brizantha Seeds
Authors: Vieira Campos Leonardo , Almeida Rodrigues Arthur , de Fátima Sales Juliana , Almeida Rodrigues Douglas , Carvalho Vasconcelos Filho Sebastião , Lino Rodrigues Cássia , Alves Vieira Dheynne , Tomaz de Castro Stella , Rubio Neto Aurélio
Published: April 2022

Efficient methodologies for automated seed quality evaluations are important for the seed industry. Advanced seed technology research requires the use of adequate methods to ensure good seed performance under adverse environmental conditions; thus, providing producers with detailed, quick, and accurate information on structural seed integrity and ensuring vigorous production. To address this problem, this study aimed to determine Brachiaria brizantha (Marandu cv., Piatã cv. and Xaraés cv.) seed quality through radiographic imaging analyses associated with vigor tests and anatomical characterizations. Brachiaria seed cultivars displaying different physical and physiological attributes were selected and subjected to the 1000-seed weight test, water content determinations, X-ray analyses, germination tests, and anatomical characterizations. The X-ray analyses made it possible to establish a relationship between the X-ray images and other determined variables. Furthermore, the X-ray images can indicate evidence of internal and external damage that could later compromise germination. The Marandu and Piatã cultivars presented the highest germination percentages, germination speed indices, normal seedling development, and cellular structure preservation compared to the Xaraés cultivar. To summarize, X-ray analyses are efficient methods used for the selection of higher physical quality cultivars and can aid in the decision-making processes of companies and seed producers worldwide.
Myrtaceae in Australia: Use of Cryobiotechnologies for the Conservation of a Significant Plant Family under Threat
Authors: Hardstaff Lyndle K. , Sommerville Karen D. , Funnekotter Bryn , Bunn Eric , Offord Catherine A. , Mancera Ricardo L.
Published: April 2022

The Myrtaceae is a very large and diverse family containing a number of economically and ecologically valuable species. In Australia, the family contains approximately 1700 species from 70 genera and is structurally and floristically dominant in many diverse ecosystems. In addition to threats from habitat fragmentation and increasing rates of natural disasters, infection by myrtle rust caused by Austropuccinia psidii is of significant concern to Australian Myrtaceae species. Repeated infections of new growth have caused host death and suppressed host populations by preventing seed set. Although most Myrtaceae species demonstrate orthodox seed storage behavior, exceptional species such as those with desiccation sensitive seed or from myrtle rust-suppressed populations require alternate conservation strategies such as those offered by cryobiotechnology. Targeting seven key Australian genera, we reviewed the available literature for examples of cryobiotechnology utilized for conservation of Myrtaceae. While there were only limited examples of successful cryopreservation for a few genera in this family, successful cryopreservation of both shoot tips and embryonic axes suggest that cryobiotechnology provides a viable alternative for the conservation of exceptional species and a potential safe storage method for the many Myrtaceae species under threat from A. psidii.
Essential Oils and Extracts of Juniperus macrocarpa Sm. and Juniperus oxycedrus L.: Comparative Phytochemical Composition and Anti-Proliferative and Antioxidant Activities
Authors: Meringolo Luciano , Bonesi Marco , Sicari Vincenzo , Rovito Simone , Passalacqua Nicodemo Giuseppe , Loizzo Monica Rosa , Tundis Rosa
Published: April 2022

In this work, we conducted a comparative phytochemical, chemotaxonomic, and biological study of essential oils (EOs) and extracts (ethyl acetate and methanol) obtained from the leaves of Juniperusmacrocarpa and J. oxycedrus. The dominant compounds of J. macrocarpa EO, analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), are α-pinene, sabinene, manoyl oxide, and germacrene D, whereas α-pinene, limonene, (Z,E)-farnesol, β-pinene, and γ-cadinene are the most representative volatiles of J. oxycedrus EOs. A multivariate analysis of EOs, included a selection of literature data comparing our samples to samples of J. oxycedrus/macrocarpa/deltoides from the Mediterranean area, was performed. As evident by high-performance liquid chromatography (HPLC) analyses, apigenin, (−)-epicatechin, and luteolin were abundant in J. oxycedrus extracts, while gallic acid, kaempferol-3-O-glucoside, and protocatechuic acid were the dominant constituents of J. macrocarpa extracts. EOs and extracts have been investigated for their potential antioxidant properties and anti-proliferative activity against lung adenocarcinoma (A549), breast cancer (MCF-7 and MDA-MB-231), and lung large cell carcinoma (COR-L23) human cell lines. The methanol and ethyl acetate extracts of J. oxycedrus exerted the most valuable antioxidant activity and exhibited the most promising activity against the COR-L23 cell line with an IC50 of 26.0 and 39.1 μg/mL, respectively, lower than that obtained with the positive control (IC50 of 45.5 μg/mL). To the best of our knowledge, this is the first report highlighting the anti-proliferative activity of J. oxycedrus and J. macrocarpa extracts against this lung cancer cell line. Our results indicate that J. oxycedrus may be considered a source of natural compounds with antioxidant and anti-proliferative effects that could be suitable for future applications.
Diversity and Content of Carotenoids and Other Pigments in the Transition from the Green to the Red Stage of Haematococcus pluvialis Microalgae Identified by HPLC-DAD and LC-QTOF-MS
Authors: Grujić Veno Jaša , Todorović Biljana , Kranvogl Roman , Ciringer Terezija , Ambrožič-Dolinšek Jana
Published: April 2022

H. pluvialis is a unicellular freshwater alga containing many bioactive compounds, especially carotenoids, which are the strongest antioxidants among the pigments. This study evaluates the composition and content of carotenoids and other pigments in both stages of algae life cycle, especially in the green vegetative stage, less studied in comparison to the red stage. To determine the composition and content of carotenoids, a combination of HPLC-DAD and LC-QTOF-MS was used. The content of carotenoids in the green vegetative stage was significantly lower than in the red vegetative stage. In the green vegetative stage, 16 different carotenoids and other pigments were identified. Among the total 8.86 mg g−1 DW of pigments, 5.24 mg g−1 DW or 59% of them were chlorophyll a with its derivatives, and 3.62 mg g−1 DW or 41% of them were free carotenoids. After the transition from the green to the red stage, the carotenoid composition was replaced by secondary carotenoids, astaxanthin and its esters, which predominated in the whole carotenoid composition. In addition to free astaxanthin, 12 astaxanthin monoesters, 6 diesters and 13 other carotenoids were determined. The majority of 37.86 mg g−1 DW pigments were monoesters. They represented 82% of all pigments, and their content was about 5 times higher than both, diesters (5.91 mg g−1 DW or 12% of all) and free carotenoids (2.4 mg g−1 DW or 6% of all). The results of the study contribute to the data on the overall pigment composition and content of H. pluvialis algae and provide the basis for further improvement of cultivation of the H. pluvialis algae.
Structure and Properties of Cellulose/Mycelium Biocomposites
Authors: Sayfutdinova Adeliya , Samofalova Irina , Barkov Artem , Cherednichenko Kirill , Rimashevskiy Denis , Vinokurov Vladimir
Published: April 2022

The current environmental problems require the use of low-energy, environmentally friendly methods and nature-like technologies for the creation of materials. In this work, we aim to study the possibility of the direct biotransformation of fibrillar cellulose by fungi through obtaining a cellulose/mycelium-based biocomposite. The cellulose micro- and nanofibrils were used as the main carbon sources in the solid-phase cultivation of basidiomycete Trametes hirsuta. The cellulose fibrils in this process act as a template for growing mycelium with the formation of well-developed net structure. The biotransformation dynamics of cellulose fibrils were studied with the help of scanning electron microscopy. The appearance of nitrogen in the structure of formed fibers was revealed by elemental analysis and FTIR-spectroscopy. The fibers diameters were estimated based on micrograph analysis and the laser diffraction method. It was shown that the diameter of cellulose fibrils can be tuned by fungi through obtaining cellulose-based mycelium fibers with a narrower diameter-size distribution as compared to the pristine cellulose fibrils. The morphology of the resulting mycelium differed when the micro or nanofibrils were used as a substrate.
Mechanical Behavior of GFRP Laminates Exposed to Thermal and Moist Environmental Conditions: Experimental and Model Assessment
Authors: Tefera Getahun , Adali Sarp , Bright Glen
Published: April 2022

This paper presents an experimental and analytical study about the mechanical response at a different temperature on glass fiber-reinforced polymer laminates. The effect of different environmental conditions on compressive, tensile, stiffness, and viscoelastic behavior (storage modulus, loss modulus and damping ratio) of laminates were investigated. Before testing, laminates were preserved in a deep freezer at −80 °C, −20 °C, 0 °C, and room temperature (25 °C) for up to 60 days. Results confirmed that temperatures ranging from −80 to 50 °C, which were below the glass transition temperature of the epoxy resin, did not significantly affect the compressive, tensile, and stiffness performance of all laminates. When the testing temperature increased to 100 °C, the properties were decreased significantly due to the damaging of the fiber/matrix interface. Additionally, results obtained from dynamic mechanical analyses tests showed a drop-in storage modulus, high peaks in loss modulus and high damping factor at the glass transition region of the epoxy resin. The highest storage modulus, two phases of glassy states and highest damping ratio on the −80/G group of laminates were obtained. The accuracy of experimental results was assessed with empirical models on the storage modulus behavior of laminates. The empirical model developed by Gibson et al. provided accurate estimates of the storage modulus as a function of temperature and frequency. The remaining empirical models were less accurate and non-conservative estimations of laminates stiffness.
Partial Biodegradable Blend for Fused Filament Fabrication: In-Process Thermal and Post-Printing Moisture Resistance
Authors: Harris Muhammad , Mohsin Hammad , Naveed Rakhshanda , Potgieter Johan , Ishfaq Kashif , Ray Sudip , Guen Marie-Joo Le , Archer Richard , Arif Khalid Mahmood
Published: April 2022

Despite the extensive research, the moisture-based degradation of the 3D-printed polypropylene and polylactic acid blend is not yet reported. This research is a part of study reported on partial biodegradable blends proposed for large-scale additive manufacturing applications. However, the previous work does not provide information about the stability of the proposed blend system against moisture-based degradation. Therefore, this research presents a combination of excessive physical interlocking and minimum chemical grafting in a partial biodegradable blend to achieve stability against in-process thermal and moisture-based degradation. In this regard, a blend of polylactic acid and polypropylene compatibilized with polyethylene graft maleic anhydride is presented for fused filament fabrication. The research implements, for the first time, an ANOVA for combined thermal and moisture-based degradation. The results are explained using thermochemical and microscopic techniques. Scanning electron microscopy is used for analyzing the printed blend. Fourier transform infrared spectroscopy has allowed studying the intermolecular interactions due to the partial blending and degradation mechanism. Differential scanning calorimetry analyzes the blending (physical interlocking or chemical grafting) and thermochemical effects of the degradation mechanism. The thermogravimetric analysis further validates the physical interlocking and chemical grafting. The novel concept of partial blending with excessive interlocking reports high mechanical stability against moisture-based degradation.
Formulation and Evaluation of Transdermal Gel Containing Tacrolimus-Loaded Spanlastics: In Vitro, Ex Vivo and In Vivo Studies
Authors: Zaki Randa Mohammed , Ibrahim Mohamed A. , Alshora Doaa H. , El Ela Amal El Sayeh Abou
Published: April 2022

Our goal was to prepare Span 60-based elastic nanovesicles (spanlastics (SPLs)) of tacrolimus (TCR) using the adapted ethanol injection method, characterize them, and evaluate their ability to improve the transdermal permeation of the active substance. The impact of two different concentrations of penetration enhancers, namely, propylene glycol and oleic acid, on the entrapment efficiency, vesicle size, and zeta potential was assessed. Moreover, in vitro release through a semipermeable membrane and ex vivo penetration through hairless rat skin were performed. Morphological examination and pharmacokinetics were performed for one selected formulation (F3OA1). TCR-loaded SPLs were effectively formulated with two different concentrations of permeation enhancers, and the effect of these enhancers on their physicochemical properties differed in accordance with the concentration and kind of enhancer used. The results of in vitro release displayed a considerable (p < 0.05) enhancement compared to the suspension of the pure drug, and there was a correlation between the in vitro and ex vivo results. The selected TCR-loaded nanovesicles incorporated into a gel base showed appreciable advantages over the oral drug suspension and the TCR-loaded gel. Additionally, the pharmacokinetic parameters were significantly (p < 0.05) improved based on our findings. Moreover, the AUC0–7 ng·h/mL form F3 OA1 was 3.36-fold higher than that after the administration of the TCR oral suspension.
Improvement of Mechanical Property for PLA/TPU Blend by Adding PLA-TPU Copolymers Prepared via In Situ Ring-Opening Polymerization
Authors: Fang Hui , Zhang Lingjie , Chen Anlin , Wu Fangjuan
Published: April 2022

Polylactic acid (PLA)-thermoplastic polyurethane (TPU) copolymer (PTC) was prepared by melting TPU pellets in molten lactide, followed by in situ ring-opening coordination polymerization. The results from FTIR and 1H-NMR confirmed the formation of the copolymer. PLA/TPU blends with different TPU contents were prepared by melt blending method. SEM and mechanical properties showed a conspicuous phase separation between PLA and TPU. In order to further improve the mechanical properties of the blend, PTC was used as the compatibilizer and the effects of the PTC content on the properties of the blend were investigated. The addition of PTC made TPU particles smaller in PLA matrix and improved the compatibility. With the loading of 5 wt.% PTC, the impact strength of the PLA/TPU blend reached 27.8 kJ/m2, which was 31.1% and 68.5% higher than that of the blend without PTC and pure PLA, respectively. As the content of PTC was more than 5 wt.%, the mechanical properties declined since the compatibilizer tended to form separate clusters, which could reduce the part distributed between the dispersed phase and the matrix, leading to a reduction in the compatibility of the blend. Moreover, the DMA results confirmed PTC could improve the compatibility between PLA and TPU.
Adaptive Fuzzy Fractional Order Global Sliding Mode Tracking Control Algorithm for Particleboard Glue System
Authors: Zhu Liangkuan , Qi Xing , Wang Peiyu
Published: April 2022

In this paper, a novel flow tracking control scheme for particleboard glue system with complex disturbance and unmeasurable system state is investigated. The method is based on hyperbolic tangent extended state observer and adaptive fuzzy fractional order global sliding mode control with exponential reaching law. The novel compound control scheme has the following advantages: Firstly, the extended state observer with hyperbolic tangent function can improve the estimation ability for the system state and complex disturbance without detailed knowledge of the controlled plant and disturbance model. Secondly, the global sliding mode control method based on fractional calculus can improve the response speed and robustness of the system, and provide a more flexible controller structure than the traditional sliding mode controller. Thirdly, the adaptive fuzzy controller is introduced to approximate the sliding mode switching term, so as to reduce the chattering phenomenon of the system. In addition, the convergence of the proposed observer and asymptotic stability of the control system are verified based on strict Lyapunov analysis. Finally, the numerical simulation results show the effectiveness of the proposed compound control scheme for particleboard glue system.
A Survey on Fault Diagnosis Approaches for Rolling Bearings of Railway Vehicles
Authors: Yan Guangxi , Chen Jiang , Bai Yu , Yu Chengqing , Yu Chengming
Published: April 2022

This paper reviews the current research status of rolling bearing fault diagnosis technology for railway vehicles. Several domains are covered, including vibration fault diagnosis, acoustic signal fault diagnosis, and temperature prediction diagnosis methods on train rolling bearing test principles and related research. The application scenarios, system diagnosis accuracies, and model structures of various studies in the literature are also compared and analyzed. Furthermore, the main technical points to be improved and the analysis of the possible research directions are proposed, which provide new research ideas for subsequent fault diagnosis methods and system innovation research and development.
Improved Foods Using Enzymes from Basidiomycetes
Authors: Berger Ralf G. , Ersoy Franziska
Published: April 2022

Within the kingdom of fungi, the division Basidiomycota represents more than 30,000 species, some with huge genomes indicating great metabolic potential. The fruiting bodies of many basidiomycetes are appreciated as food (“mushrooms”). Solid-state and submerged cultivation processes have been established for many species. Specifically, xylophilic fungi secrete numerous enzymes but also form smaller metabolites along unique pathways; both groups of compounds may be of interest to the food processing industry. To stimulate further research and not aim at comprehensiveness in the broad field, this review describes some recent progress in fermentation processes and the knowledge of fungal genetics. Processes with potential for food applications based on lipases, esterases, glycosidases, peptidases and oxidoreductases are presented. The formation and degradation of colourants, the degradation of harmful food components, the formation of food ingredients and particularly of volatile and non-volatile flavours serve as examples. In summary, edible basidiomycetes are foods—and catalysts—for food applications and rich donors of genes to construct heterologous cell factories for fermentation processes. Options arise to support the worldwide trend toward greener, more eco-friendly and sustainable processes.
Mechanism of Particle Agglomeration for Single and Multi-Nozzle Atomization in Spray Drying: A Review
Authors: Zbicinski Ireneusz , Ciesielski Krzysztof , Ge Bangguo
Published: April 2022

This paper reviews experimental works on the effects of single nozzle location and multi-nozzle atomization on the mechanism of particle agglomeration in spray drying. In addition to the naturally occurring primary agglomeration, forced and secondary agglomeration is observed as an effect of different nozzle positions or multiple-nozzle atomization in spray drying. Particle size diameters in the spray drying process for atomization from a single nozzle located at the top of the tower are larger than at the bottom of the tower because of the lower ambient air temperatures and longer residence time in the agglomeration zone. The trend of reduction in particle size is observed in all analyzed works when the nozzle is moved down towards the air inlet, due to droplets’ exposure to higher air temperatures and shorter residence time in the drying chamber. Conditions of droplet–droplet, dry–dry or sticky–dry collisions leading to the development of coalescence, agglomeration and rebound zones for multiple-nozzle atomization are described and discussed. Typically, log normal PSD was found for single-nozzle spraying whereas for multi nozzle arrangement, bi-modal particle size distribution was found both for drying in lab and industrial scale.
Audio Compensation with Cascade Biquad Filters for Feedback Active Noise Control Headphones
Authors: An Fengyan , Wu Qianqian , Liu Bilong
Published: April 2022

In active noise control (ANC) headphones, the audio signal is modified together with the primary noise if a feedback controller is used. Although this problem can be alleviated with an FIR model of the secondary path, practical implementations are usually restricted by its computational complexity. In this paper, cascade biquad filters are used to compensate for the modification of the audio system. Instead of using classical identification methods with an IIR model, the audio compensation problem is fixed through an optimization process. An objective function evaluating the comprehensive compensation performance is proposed, whose minimum value is obtained using the differential evolution (DE) algorithm. Simulations and experiments are carried out, whose results validate the effectiveness and efficiency of the proposed optimization method. The averaged compensation error can be reduced to about 0.5 dB with only two to five biquad filters.
Artificial Intelligence, Deep Aging Clocks, and the Advent of ‘Biological Age’: A Christian Critique of AI-Powered Longevity Medicine with Particular Reference to Fasting
Authors: Daly Todd T. W.
Published: April 2022

I argue that the use of artificial intelligence (AI) in longevity medicine to slow human aging encourages individuals to see themselves as managers of their own biology. While such a stance is not entirely unwarranted, it may nevertheless preclude other perspectives of the body as it relates to spiritual formation: namely, the Christian discipline of fasting. Using a christological anthropology informed by Karl Barth, I explore the potential impact of AI-fueled markers such as deep aging clocks (DACs) and the related technological construct of “biological age” (as distinct from chronological age) and how this construct might impact the Christian practice of fasting.
Revenging Vestments: On the Chasubles of the Bishops Ildefonsus and Adaulfus (Toledo and Compostela, Tenth–Twelfth Centuries)
Authors: Lorenzo-Rodríguez Abel
Published: April 2022

This article will analyze the miracle of St. Ildefonsus’ chasuble (606–667) from the point of view of miracles of punishment. In comparison to previous studies, on this occasion, the Toledan story will be reconsidered not only together with that of St. Bonitus of Clermont (620–700), but also in light of the similarities with the miracle of the bishop Adaulfus II of Compostela (ninth century), and the possible late antique inspiration of both from the Libellus Precum and from Gregory of Tours´ hagiographies. The stories that involve Ildefonsus and Adaulfus have strong similarities in the development of their sainthoods and in the importance that is given to liturgical vestments. Both are sanctified as prelates, which is due to their miraculous possession of external attributes because of their merits when facing unfair trials.
Machine Learning in Ratemaking, an Application in Commercial Auto Insurance
Authors: Matthews Spencer , Hartman Brian
Published: April 2022

This paper explores the tuning and results of two-part models on rich datasets provided through the Casualty Actuarial Society (CAS). These datasets include bodily injury (BI), property damage (PD) and collision (COLL) coverage, each documenting policy characteristics and claims across a four-year period. The datasets are explored, including summaries of all variables, then the methods for modeling are set forth. Models are tuned and the tuning results are displayed, after which we train the final models and seek to explain select predictions. Data were provided by a private insurance carrier to the CAS after anonymizing the dataset. These data are available to actuarial researchers for well-defined research projects that have universal benefit to the insurance industry and the public. Our hope is that the methods demonstrated here can be a good foundation for future ratemaking models to be developed and tested more efficiently.
SAR Target Recognition Using cGAN-Based SAR-to-Optical Image Translation
Authors: Sun Yuchuang , Jiang Wen , Yang Jiyao , Li Wangzhe
Published: April 2022

Target recognition in synthetic aperture radar (SAR) imagery suffers from speckle noise and geometric distortion brought by the range-based coherent imaging mechanism. A new SAR target recognition system is proposed, using a SAR-to-optical translation network as pre-processing to enhance both automatic and manual target recognition. In the system, SAR images of targets are translated into optical by a modified conditional generative adversarial network (cGAN) whose generator with a symmetric architecture and inhomogeneous convolution kernels is designed to reduce the background clutter and edge blur of the output. After the translation, a typical convolutional neural network (CNN) classifier is exploited to recognize the target types in translated optical images automatically. For training and testing the system, a new multi-view SAR-optical dataset of aircraft targets is created. Evaluations of the translation results based on human vision and image quality assessment (IQA) methods verify the improvement of image interpretability and quality, and translated images obtain higher average accuracy than original SAR data in manual and CNN classification experiments. The good expansibility and robustness of the system shown in extending experiments indicate the promising potential for practical applications of SAR target recognition.
Deep Feature Migration for Real-Time Mapping of Urban Street Shading Coverage Index Based on Street-Level Panorama Images
Authors: Yue Ning , Zhang Zhenxin , Jiang Shan , Chen Siyun
Published: April 2022

Urban street shadows can provide essential information for many applications, such as the assessment and protection of ecology and environment, livability evaluation, etc. In this research, we propose an effective and rapid method to quantify the diurnal and spatial changes of urban street shadows, by taking Beijing city as an example. In the method, we explore a novel way of transferring street characteristics to semantically segment street-level panoramic images of Beijing by using DeepLabv3+. Based on the segmentation results, the shading situation is further estimated by projecting the path of the sun in a day onto the semantically segmented fisheye photos and applying our firstly defined shading coverage index formula. Experimental results show that in several randomly selected sampling regions in Beijing, our method can successfully detect more than 83% of the shading changes compared to the ground truth. The results of this method contribute to the study of urban livability and the evaluation of human life comfort. The quantitative evaluation method of the shading coverage index proposed in this research has certain promotion significance and can be applied to shading-related research in other cities.
A New Method for Long-Term River Discharge Estimation of Small- and Medium-Scale Rivers by Using Multisource Remote Sensing and RSHS: Application and Validation
Authors: Lou Hezhen , Zhang Yujia , Yang Shengtian , Wang Xuelei , Pan Zihao , Luo Ya
Published: April 2022

River discharge is an important hydrological parameter of river water resources. Especially in small- and medium-scale rivers, data deficiency is the biggest problem for studies of river discharge. In recent years, remote sensing has become a rapid and convenient method to estimate river discharge. However, remote sensing images still have some difficulty generating continuous long-term river discharge. To address this problem, we developed a new method coupling the remote sensing hydrology station method (RSHS) with statistical regression downscaling, using data from optical satellites (Landsat-8, Sentinel-2), radar satellites (Sentinel-1), and un-manned aerial vehicles (UAVs). We applied this method to monitor monthly river discharge for small- and medium-scale rivers from 2016 to 2020 on Yunnan-Guizhou Plateau and evaluated the accuracy of the results. The results show that (1) by applying the newly constructed method, the water body continuity index obtained by Landsat-8 increased by 7% and the average river length percentage in the channel reached 90.7%, a 40% increase; (2) there were only 10 river flow data points, on average, in the 5-year period obtained before this method was applied; after this method was applied, more than 50 river flow data points could be obtained, on average, extending the quantity of data fivefold; in addition, improper extreme values could also be avoided; (3) with better continuity of water body distribution, the images provided steadier river widths. The relative error of daily flow estimation from Landsat-8 images was reduced by 60% and the mean percentage error was reduced by one-fourth. The relative error of the multisource remote sensing composited flow was reduced by 37% with a reduction in the mean percentage error of over a half; (4) in addition, we found that when the threshold difference between water bodies and land in remote sensing images is more than 0.2, the impact of water body recognition error on flow accuracy can be ignored. This method helps to overcome the absence of remote sensing methods for the long-term estimation of flow series in small- and medium-scale rivers, improves the accuracy of remote sensing methods for calculating flow, and provides ideas for regional water resource management and utilization.
Distortionless 1/2 Overlap Windowing in Frequency Domain Anti-Jamming of Satellite Navigation Receivers
Authors: Lu Zukun , Song Jie , Huang Long , Ren Chao , Xiao Zhibin , Li Baiyu
Published: April 2022

Frequency-domain anti-jamming technology is a common anti-jamming method for satellite navigation receivers. 1/2 overlapping windowing can effectively solve the spectrum leakage in the frequency domain conversion process, but the traditional window function will cause the loss of signal energy. This paper proposes a window function design method with no loss of signal energy, which can effectively solve the signal energy loss caused by the window function. The feasibility of the proposed method is theoretically deduced, and the effectiveness of the proposed method is verified by simulation and measured data. Compared with the traditional window function, the signal-to-noise ratio improvement of the method proposed in this paper is better than 0.5 dB. The frequency domain anti-jamming processing is optimized, the signal-to-noise ratio loss caused by the anti-jamming processing is reduced, and the anti-jamming performance is indirectly improved. This plays an important role in the performance optimization of satellite navigation system links.
Land Use Hotspots of the Two Largest Landlocked Countries: Kazakhstan and Mongolia
Authors: Yuan Jing , Chen Jiquan , Sciusco Pietro , Kolluru Venkatesh , Saraf Sakshi , John Ranjeet , Ochirbat Batkhishig
Published: April 2022

As the two largest landlocked countries, Kazakhstan and Mongolia have similar biophysical conditions and socioeconomic roots in the former Soviet Union. Our objective is to investigate the direction, extent, and spatial variation of land cover change at three administrative levels over three decades (1990–2020). We selected three provinces from each country (Aktobe, Akmola, and Almaty province in Kazakhstan, and Arkhangai, Tov, and Dornod in Mongolia) to classify the land cover into forest, grassland, cropland, barren, and water. Altogether, 6964 Landsat images were used in pixel-based classification method with random forest model for image processing. Six thousand training data points (300 training points × 5 classes × 4 periods) for each province were collected for classification and change detection. Land cover changes at decadal and over the entire study period for five land cover classes were quantified at the country, provincial, and county level. High classification accuracy indicates localized land cover classification have an edge over the latest global land cover product and reveal fine differences in landscape composition. The vast steppe landscapes in these two countries are dominated by grasslands of 91.5% for Dornod in Mongolia and 74.7% for Aktobe in Kazakhstan during the 30-year study period. The most common land cover conversion was grassland to cropland. The cyclic land cover conversions between grassland and cropland reflect the impacts of the Soviet Union’s largest reclamation campaign of the 20th century in Kazakhstan and the Atar-3 agriculture re-development in Mongolia. Kazakhstan experienced a higher rate of land cover change over a larger extent of land area than Mongolia. The spatial distribution of land use intensity indicates that land use hotspots are largely influenced by policy and its shifts. Future research based on these large-scale land use and land cover changes should be focused the corresponding ecosystem and society functions.
Full-Resolution Quality Assessment for Pansharpening
Authors: Scarpa Giuseppe , Ciotola Matteo
Published: April 2022

A reliable quality assessment procedure for pansharpening methods is of critical importance for the development of the related solutions. Unfortunately, the lack of ground truths to be used as guidance for an objective evaluation has pushed the community to resort to two approaches, which can also be jointly applied. Hence, two kinds of indexes can be found in the literature: (i) reference-based reduced-resolution indexes aimed to assess the synthesis ability; (ii) no-reference subjective quality indexes for full-resolution datasets aimed to assess spectral and spatial consistency. Both reference-based and no-reference indexes present critical shortcomings, which motivate the community to explore new solutions. In this work, we propose an alternative no-reference full-resolution assessment framework. On one side, we introduce a protocol, namely the reprojection protocol, to take care of the spectral consistency issue. On the other side, a new index of the spatial consistency between the pansharpened image and the panchromatic band at full resolution is also proposed. Experimental results carried out on different datasets/sensors demonstrate the effectiveness of the proposed approach.
Heart Rate Variability from Wearable Photoplethysmography Systems: Implications in Sleep Studies at High Altitude
Authors: Castiglioni Paolo , Meriggi Paolo , Di Rienzo Marco , Lombardi Carolina , Parati Gianfranco , Faini Andrea
Published: April 2022

The interest in photoplethysmography (PPG) for sleep monitoring is increasing because PPG may allow assessing heart rate variability (HRV), which is particularly important in breathing disorders. Thus, we aimed to evaluate how PPG wearable systems measure HRV during sleep at high altitudes, where hypobaric hypoxia induces respiratory disturbances. We considered PPG and electrocardiographic recordings in 21 volunteers sleeping at 4554 m a.s.l. (as a model of sleep breathing disorder), and five alpine guides sleeping at sea level, 6000 m and 6800 m a.s.l. Power spectra, multiscale entropy, and self-similarity were calculated for PPG tachograms and electrocardiography R–R intervals (RRI). Results demonstrated that wearable PPG devices provide HRV measures even at extremely high altitudes. However, the comparison between PPG tachograms and RRI showed discrepancies in the faster spectral components and at the shorter scales of self-similarity and entropy. Furthermore, the changes in sleep HRV from sea level to extremely high altitudes quantified by RRI and PPG tachograms in the five alpine guides tended to be different at the faster frequencies and shorter scales. Discrepancies may be explained by modulations of pulse wave velocity and should be considered to interpret correctly autonomic alterations during sleep from HRV analysis.
Urban Warming of the Two Most Populated Cities in the Canadian Province of Alberta, and Its Influencing Factors
Authors: Ejiagha Ifeanyi R. , Ahmed M. Razu , Dewan Ashraf , Gupta Anil , Rangelova Elena , Hassan Quazi K.
Published: April 2022

Continuous urban expansion transforms the natural land cover into impervious surfaces across the world. It increases the city’s thermal intensity that impacts the local climate, thus, warming the urban environment. Surface urban heat island (SUHI) is an indicator of quantifying such local urban warming. In this study, we quantified SUHI for the two most populated cities in Alberta, Canada, i.e., the city of Calgary and the city of Edmonton. We used the moderate resolution imaging spectroradiometer (MODIS) acquired land surface temperature (LST) to estimate the day and nighttime SUHI and its trends during 2001–2020. We also performed a correlation analysis between SUHI and selected seven influencing factors, such as urban expansion, population, precipitation, and four large-scale atmospheric oscillations, i.e., Sea Surface Temperature (SST), Pacific North America (PNA), Pacific Decadal Oscillation (PDO), and Arctic Oscillation (AO). Our results indicated a continuous increase in the annual day and nighttime SUHI values from 2001 to 2020 in both cities, with a higher magnitude found for Calgary. Moreover, the highest value of daytime SUHI was observed in July for both cities. While significant warming trends of SUHI were noticed in the annual daytime for the cities, only Calgary showed it in the annual nighttime. The monthly significant warming trends of SUHI showed an increasing pattern during daytime in June, July, August, and September in Calgary, and March and September in Edmonton. Here, only Calgary showed the nighttime significant warming trends in March, May, and August. Further, our correlation analysis indicated that population and built-up expansion were the main factors that influenced the SUHI in the cities during the study period. Moreover, SST indicated an acceptable relationship with SUHI in Edmonton only, while PDO, PNA, and AO did not show any relation in either of the two cities. We conclude that population, built-up size, and landscape pattern could better explain the variations of the SUHI intensity and trends. These findings may help to develop the adaptation and mitigating strategies in fighting the impact of SUHI and ensure a sustainable city environment.
K-Means Clustering-Based Safety System in Large-Scale Industrial Site Using Industrial Wireless Sensor Networks
Authors: Seo Dongyeong , Kim Sangdae , Oh Seungmin , Kim Sang-Ha
Published: April 2022

A large number of workers and heavy equipment are used in most industrial sizes, and the prevention of safety accidents is one of the most important issues. Therefore, although a number of systems have been proposed to prevent accidents, existing studies assume that workers are gathered in some areas. These assumptions are not suitable for large-scale industrial sites in which workers form as a group and work in a large area. In other words, in a large-scale industrial site, existing schemes are unsuitable for the timely notifying of warnings of threats, and excessive energy is consumed. Therefore, we propose a k-means clustering-based safety system for a large-scale industrial site. In the proposed scheme, workers deployed over a large area are divided into an appropriate number of groups, and threat notification is delivered by a multicasting tree toward each cluster. The notification to workers is delivered through local flooding in each cluster. The simulation results show that the system is able to deliver the notification within a valid time, and it is energy efficient compared to the existing scheme.
Surface Plasmon Resonance (SPR) Spectroscopy and Photonic Integrated Circuit (PIC) Biosensors: A Comparative Review
Authors: Steglich Patrick , Lecci Giulia , Mai Andreas
Published: April 2022

Label-free direct-optical biosensors such as surface-plasmon resonance (SPR) spectroscopy has become a gold standard in biochemical analytics in centralized laboratories. Biosensors based on photonic integrated circuits (PIC) are based on the same physical sensing mechanism: evanescent field sensing. PIC-based biosensors can play an important role in healthcare, especially for point-of-care diagnostics, if challenges for a transfer from research laboratory to industrial applications can be overcome. Research is at this threshold, which presents a great opportunity for innovative on-site analyses in the health and environmental sectors. A deeper understanding of the innovative PIC technology is possible by comparing it with the well-established SPR spectroscopy. In this work, we shortly introduce both technologies and reveal similarities and differences. Further, we review some latest advances and compare both technologies in terms of surface functionalization and sensor performance.