bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of the Microstructure, Thermal Properties, and Mechanical Properties of Sn-Bi-Ag and Sn-Bi-Ag-Si Low Temperature Lead-Free Solder Alloys
Authors: Chen Sheng , Wang Xinbao , Guo Zhiqiu , Wu Changjun , Liu Yongxiong , Liu Ya , Su Xuping
Published: January 2023

In this study, we investigated the microstructure, mechanical properties, and thermal performance of Sn-xBi-1Ag (x = 35, 37, 45, and 47 wt.%) solders, with a particular focus on the effect of adding trace Si atoms. The impact of different Ag concentrations on the properties of Sn-xBi-Ag-0.5Si solders was also studied. The results indicated that as the amount of Bi added to Sn-xBi-1Ag solder alloys increased, the tensile strength, microhardness, melting temperature, and melting range decreased somewhat, but the wettability improved. The Cu6Sn5 layer between the soldering alloy and the Cu substrate became thinner upon increasing the Bi content. Adding microcrystalline Si atoms to the Sn-Bi-1Ag alloy improved the tensile strength and microhardness, but the melting point and melting range were not significantly changed. The wettability was optimized, and the diffusion layer formed with the Cu matrix was significantly thinner. By increasing the Ag content in the Sn-Bi-(1,3)Ag-0.5Si alloy, the tensile strength of the alloy was continuously strengthened, while the hardness decreased slightly and the melting point and melting range increased slightly. The wettability was greatly improved, and the Cu6Sn5 layer became thinner.
Features of the Oxidation of Multilayer (TiAlCrSiY)N/(TiAlCr)N Nanolaminated PVD Coating during Temperature Annealing
Authors: Kovalev Anatoly Ivanovich , Vakhrushev Vladimir Olegovich , Konovalov Egor Pavlovich , Fox-Rabinovich German Simonovich , Wainstein Dmitry Lvovich , Dmitrievskii Stanislav Alekseevich , Mukhsinova Alise Denisovna
Published: January 2023

A nano-multilayer Ti0.2Al0.55Cr0.2Si0.03Y0.02N/Ti0.25Al0.65Cr0.1N PVD coating was deposited on Kennametal carbide K 313 inserts. These coatings are widely used to protect cutting tools under severe exploitation conditions. Under equilibrium conditions, it was found that the Al2O3 oxide possessed better adhesive properties than the TiO2. The addition of chromium further enhanced the oxidation resistance of the coatings. Silicon significantly increased the oxidation resistance of this type of coating. The properties of the diffusion process in this coating have not been sufficiently investigated, despite the considerable number of articles published on this topic. For the purpose of this study, a multilayer ion-plasma (TiAlCrSiY)N/(TiAlCr)N coating was oxidized under equilibrium conditions; its chemical inhomogeneity was studied by time-of-flight mass spectroscopy using a TOF SIMS5-100 instrument. The data was collected from an area of 100 × 100 µ. A D-300 profilometer (KLA-Tencor Corp., Milpitas, California 95035, USA) was used to determine the rate of ion etching. It was found that oxidation commenced at the surface nanolayer of a TiAlCrN nitride, forming loose films of Cr2O3, TiO2, and Al2O3 oxides. This passivating film had a thickness of around 140 nm. For the first time, the interlayer diffusion coefficients of Si and Y were determined in multilayer coatings based on Ti0.2Al0.55Cr0.2Si0.03Y0.02N/Ti0.25Al0.65Cr0.1N, under open air annealing at 700 °C. The physical nature of the differences in the diffusion of these elements is discussed. The diffusion rate in the near-surface volumes was lower than in the deep layers of the multilayer coating, most likely due to the formation of passivating oxide films on the surface.
Assessing the Effects of Different Fillers and Moisture on Asphalt Mixtures’ Mechanical Properties and Performance
Authors: Liang Yongcai , Bai Tao , Zhou Xiaolong , Wu Fan , Chenxin Changlong , Peng Chao , Fuentes Luis , Walubita Lubinda F. , Li Wei , Wang Xingchen
Published: January 2023

This laboratory study was conducted to comparatively assess the effects of different fillers and moisture on the mechanical properties and performance of asphalt mixtures. In the study, a typical Pen70 base asphalt was modified with four different filler materials, namely limestone powder, cement, slaked (hydrated) lime, and brake pad powder, to produce different asphalt mortars that were subsequently used to prepare the asphalt mixtures. Thereafter, various laboratory tests, namely dynamic uniaxial repeated compressive loading, freeze-thaw splitting, and semicircular bending (SCB) were conducted to evaluate the moisture sensitivity, high-temperature stability, low-temperature cracking, and fatigue performance of the asphalt mixtures before and after being subjected to water saturation conditions. Overall, the study results indicated superior moisture tolerance, water damage resistance, and performance for slaked (hydrated) lime, consecutively followed by brake pad powder, cement, and limestone powder. That is, for the materials evaluated and the laboratory test conditions considered, limestone mineral powder was found to be the most moisture-sensitive filler material, whilst slaked (hydrated) lime was the most moisture-tolerant and water-damage resistant filler material.
Photocured Composite Films with Microfibrillated Cellulose: A Study of Water Vapor Permeability
Authors: Amior Aicha , Satha Hamid , Vitale Alessandra , Bongiovanni Roberta , Dalle Vacche Sara
Published: January 2023

Photocuring is a crosslinking process, widely employed to produce polymers in the form of film. As it is an environmentally friendly process, it is particularly interesting for the preparation of sustainable materials and composites. In this work, composite self-standing films were obtained combining microfibrillated cellulose (MFC) and photocured matrices. To understand the influence of the polarity and surface tension of the matrix on the properties of the composite, poly(ethylene glycol) diacrylate was selected as a hydrophilic matrix and soybean oil epoxidized acrylate as a hydrophobic matrix. Furthermore, the weight fraction of MFC also varied. The conversion and rate of the curing reaction, and the water vapor permeability were studied and discussed in the light of the morphology and composition of the composites.
Effect of Boron Doping Concentration on the Wettability and Surface Free Energy of Polycrystalline Boron-Doped Diamond Film
Authors: Wang Peng , Yu Qiyuan , Yuan Xiaoxi , Cui Zheng , Liu Yaofeng , Gao Nan , Jin Huichao , Cheng Shaoheng , Liu Junsong , Li Hongdong
Published: January 2023

The wettability and surface free energy of diamonds are crucial for their applications. In this study, polycrystalline boron-doped diamond (PBDD) films with different boron doping concentrations were prepared, and the effect of the boron doping concentration on the wettability and surface free energy (SFE) of the film was investigated. The SFEs of the PBDD films were investigated by employing the surface tension component approach and the equation-of-state approach. The investigation suggested that the alternative formulation of Berthelot’s rule, the Lifshitz-van der Waals/acid-base (van Oss) approach, and the Owens-Wendt-Kaelble approach were suitable for estimating the SFEs of PBDD films, whereas the Fowkes approach, Berthelot’s (geometric mean) combining rule, and Antonow’s rule could not provide reliable results. Results showed that the SFEs of PBDD films increased with increasing boron doping concentration, and the SFEs were 43.26–49.66 mJ/m2 (Owens-Wendt-Kaelble approach), 42.89–52.26 mJ/m2 (Lifshitz-van der Waals/acid-base), and 44.38–48.73 mJ/m2 (alternative formulation of Berthelot’s rule). This study also provides a reference for the application of empirical and physics-based semi-empirical approaches to SFE estimation.
Investigation of the Microstructure and Wear Properties of Laser Clad Al-Si Coatings Containing Different Y2O3 Contents
Authors: Zhang Dongdong , He Xiya , Gao Yali , Qin Baolong
Published: January 2023

Y2O3-reinforced Al-Si alloy coatings were prepared on the surface of a Mg alloy by the laser cladding technique. The microstructure, hardness, and wear resistance of the coatings were analyzed using an X-ray diffractometer, a scanning electron microscope, an energy spectrometer, a Vickers hardness tester, and a friction wear tester. The effect of different additions of Y2O3 on the microstructure and properties of the coatings was investigated. The results indicate that the addition of Y2O3 leads to a significant refinement of the grain size and a denser microstructure of the coatings. Coatings with a high Y2O3 content provide superior hardness and wear resistance. With a Y2O3 content of 7.5 wt.%, the coating exhibits the finest grain size, highest hardness, and smallest wear volume. Excessive amounts of Y2O3, however, cause a reduction in the surface properties of the coating.
Experiments and Evaluation of a Container Migration Data-Auditing System on Edge Computing Environment
Authors: Uchibayashi Toshihiro , Apduhan Bernady , Suganuma Takuo , Hiji Masahiro
Published: January 2023

With the proliferation of IoT sensors and devices, storing collected data in the cloud has become common. A wide variety of data with different purposes and forms are not directly stored in the cloud but are sent to the cloud via edge servers. At the edge server, applications are running in containers and virtual machines to collect data. However, the current deployment and movement mechanisms for containers and virtual machines do not consider any conventions or regulations for the applications and the data it contains. Therefore, it is easy to deploy and migrate containers and virtual machines. However, the problem arises when it is deployed or migrated, which may violate the licensing terms of the contained applications, the rules of the organization, or the laws and regulations of the concerned country. We have already proposed a data-audit control mechanism for the migration of virtual machines. The proposed mechanism successfully controls the unintentional and malicious migration of virtual machines. We expect similar problems with containers to occur as the number of edge servers increases. Therefore, we propose a policy-based data-audit control system for container migration. The proposed system was verified in the implemented edge computing environment and the results showed that adding the proposed data-audit control mechanism had a minimal impact on migration time and that the system was practical enough. In the future, we intend to conduct verification not in a very compact and short-range environment such as this one but on an existing wide-area network.
Vegetative Recovery of Yerba-Mate (Ilex paraguariensis St. Hil) Crop by Coppicing
Authors: Valduga Alice Teresa , Magri Ederlan , Cominetti Janice , Gonçalves Itamar Luís , Navarini Bampi Edivania , Cansian Rogério Luís , Zanin Elisabete Maria
Published: January 2023

Background: Yerba-mate (Ilex paraguariensis) is a perennial native tree from South America. Improper management of yerba-mate crops results in low yield. This work evaluated the recovery and the vegetative capacity of the crop after coppicing. Methods: A 2-year field observation approach was used and the study area was monitored from 2019 to 2021 in a 20-year-old yerba-mate crop with low yield. Drastic coppicing was used as a strategy, aiming to study the effect of the month and the height of pruning. Four groups were defined combining the trunk heights of 10 and 40 cm and the months of pruning June and August. Results: Yerba-mate plants showed a low mortality rate of 2%. In the first year after the intervention, the height of the cutting was the most important factor that influenced the amount of primary and secondary branches, validating response surfaces with r2 values of 0.9942 and 0.9084, respectively. In the second year of the experiment, full recovery in productivity was reached, with a mean rise of 109.7% in the plants of the group coppiced in June 40 cm above the soil. Conclusion: The techniques used in this study are appropriate for vigor recovery in yerba-mate plants inadequately managed and allow a new architecture on plants, enabling mechanical harvesting.
Comparative Transcriptomic Analysis Reveals Variable Responses to the Brown Planthopper Nilaparvata lugens in Different Rice Cultivars
Authors: Shi Longqing , He Haifang , Zhang Junian , Jiang Zhaowei , Qiu Liangmiao , Zhan Zhixiong
Published: January 2023

Rice is an indispensable crop in East and Southeast Asia, and the study of its biological characteristics has important value. We observed that different cultivars of rice have different levels of resistance to the brown planthopper (BPH), Nilaparvata lugens. In this study, transcriptome sequencing was used to analyze the differentially expressed genes (DEGs) of three rice varieties caused by BPH damage combined with physical stimulation and controls. We performed weighted correlation network analysis (WGCNA) and found a module positively related to physical stimulation. KEGG analysis showed that this module is strongly related to the ribosome pathway. Through comparative analysis with controls, we found the differential genes of each cultivar after BPH damage; through trend analysis, we found the differential genes shared by the three varieties after BPH damage. The KEGG/GO enrichment analysis of these genes found that they are mainly functionally concentrated in signal transduction, redox reactions, etc. The results of this research will be helpful to study the molecular mechanism of the BPH-rice interaction, identify resistance genes, and facilitate further studies on molecular resistance breeding and pest control.
MOCVD-grown β-Ga2O3 as a Gate Dielectric on AlGaN/GaN-Based Heterojunction Field Effect Transistor
Authors: Hasan Samiul , Jewel Mohi Uddin , Crittenden Scott R. , Lee Dongkyu , Avrutin Vitaliy , Özgür Ümit , Morkoç Hadis , Ahmad Iftikhar
Published: January 2023

We report the electrical properties of Al0.3Ga0.7N/GaN heterojunction field effect transistor (HFET) structures with a Ga2O3 passivation layer grown by metal–organic chemical vapor deposition (MOCVD). In this study, three different thicknesses of β-Ga2O3 dielectric layers were grown on Al0.3Ga0.7N/GaN structures leading to metal-oxide-semiconductor-HFET or MOSHFET structures. X-ray diffraction (XRD) showed the (2¯01) orientation peaks of β-Ga2O3 in the device structure. The van der Pauw and Hall measurements yield the electron density of ~ 4 × 1018 cm−3 and mobility of ~770 cm2V−1s−1 in the 2-dimensional electron gas (2DEG) channel at room temperature. Capacitance–voltage (C-V) measurement for the on-state 2DEG density for the MOSHFET structure was found to be of the order of ~1.5 × 1013 cm−2. The thickness of the Ga2O3 layer was inversely related to the threshold voltage and the on-state capacitance. The interface charge density between the oxide and Al0.3Ga0.7N barrier layer was found to be of the order of ~1012 cm2eV−1. A significant reduction in leakage current from ~10−4 A/cm2 for HFET to ~10−6 A/cm2 for MOSHFET was observed well beyond pinch-off in the off-stage at -20 V applied gate voltage. The annealing at 900° C of the MOSHFET structures revealed that the Ga2O3 layer was thermally stable at high temperatures resulting in insignificant threshold voltage shifts for annealed samples with respect to as-deposited (unannealed) structures. Our results show that the MOCVD-gown Ga2O3 dielectric layers can be a strong candidate for stable high-power devices.
Effect of Thermal Exposure on Mechanical Properties of Al-Si-Cu-Ni-Mg Aluminum Alloy
Authors: Chen Fanming , Liu Chengwen , Zuo Lijie , Wu Zhiyuan , He Yiqiang , Dong Kai , Li Guoqing , He Weiye
Published: January 2023

The microstructure morphology and evolution of mechanical properties are investigated in this study. The results show that the phases displayed no clear change after thermal exposure at 250 °C for 200 h. The tensile strength of the as-cast alloy showed a downward trend in different degrees with the increase in the tensile temperature, while the influence of elongation was opposite to the tensile strength. In addition, the tensile strength tended to be stable after thermal exposure at 250 °C for 100 h. The main creep mechanism of the as-cast alloy at a low temperature and low stress (T ≤ 250 °C; σ ≤ 40 MPa) is grain-boundary creep. The Monkman–Grant empirical formula was used to fit the relationship between the creep life and the minimum creep rate, and the fitting results are: tr·ε˙min0.95=0.207.
Burning Rate Prediction of Solid Rocket Propellant (SRP) with High-Energy Materials Genome (HEMG)
Authors: Pang Weiqiang , Abrukov Victor , Anufrieva Darya , Chen Dongping
Published: January 2023

High-energy materials genome (HEMG) is an analytical and calculation tool that contains relationships between variables of the object, which allows researchers to calculate the values of one part of the variables through others, solve direct and inverse tasks, predict the characteristics of non-experimental objects, predict parameters to obtain an object with desired characteristics and execute virtual experiments for conditions which cannot be organized or have difficultly being organized. HEMG is based on experimental data on the burning rate of various high-energy materials (HEMs) under various conditions, on the metadata on the quantum and physicochemical characteristics of HEMs components as well as on thermodynamic characteristics of HEMs as a whole. The history and current status of the emergence of HEMG are presented herein. The fundamental basis of the artificial neural networks (ANN) as a methodological HEMG base, as well as some examples of HEMG conception used to create multifactor computational models (MCM) of solid rocket propellants (SRP) combustion, is presented.
Dual-Tracer PET-MRI-Derived Imaging Biomarkers for Prediction of Clinically Significant Prostate Cancer
Authors: Grubmüller Bernhard , Huebner Nicolai A. , Rasul Sazan , Clauser Paola , Pötsch Nina , Grubmüller Karl Hermann , Hacker Marcus , Hartenbach Sabrina , Shariat Shahrokh F. , Hartenbach Markus , Baltzer Pascal
Published: January 2023

Purpose: To investigate if imaging biomarkers derived from 3-Tesla dual-tracer [(18)F]fluoromethylcholine (FMC) and [68Ga]Ga-PSMAHBED-CC conjugate 11 (PSMA)-positron emission tomography can adequately predict clinically significant prostate cancer (csPC). Methods: We assessed 77 biopsy-proven PC patients who underwent 3T dual-tracer PET/mpMRI followed by radical prostatectomy (RP) between 2014 and 2017. We performed a retrospective lesion-based analysis of all cancer foci and compared it to whole-mount histopathology of the RP specimen. The primary aim was to investigate the pretherapeutic role of the imaging biomarkers FMC- and PSMA-maximum standardized uptake values (SUVmax) for the prediction of csPC and to compare it to the mpMRI-methods and PI-RADS score. Results: Overall, we identified 104 cancer foci, 69 were clinically significant (66.3%) and 35 were clinically insignificant (33.7%). We found that the combined FMC+PSMA SUVmax were the only significant parameters (p < 0.001 and p = 0.049) for the prediction of csPC. ROC analysis showed an AUC for the prediction of csPC of 0.695 for PI-RADS scoring (95% CI 0.591 to 0.786), 0.792 for FMC SUVmax (95% CI 0.696 to 0.869), 0.852 for FMC+PSMA SUVmax (95% CI 0.764 to 0.917), and 0.852 for the multivariable CHAID model (95% CI 0.763 to 0.916). Comparing the AUCs, we found that FMC+PSMA SUVmax and the multivariable model were significantly more accurate for the prediction of csPC compared to PI-RADS scoring (p = 0.0123, p = 0.0253, respectively). Conclusions: Combined FMC+PSMA SUVmax seems to be a reliable parameter for the prediction of csPC and might overcome the limitations of PI-RADS scoring. Further prospective studies are necessary to confirm these promising preliminary results.
Socioenvironmental and Spatial Criteria as Tools for the Management and Conservation of Hydrozoans in Protected and Unprotected Areas
Authors: Estrada-González Mariae C. , Jiménez-López María Esther , Huato-Soberanis Leonardo , Mendoza-Becerril María A.
Published: January 2023

The cnidarians of the class Hydrozoa comprise 3720 species, are globally distributed, and can have complex life cycles. In the Espíritu Santo Archipelago (ESA), Mexico, hydrozoans are understudied, and, for this reason, the present work describes the taxocene of hydrozoans and their oceanographic preferences in the area. Hydrozoans were collected at 12 sampling stations in the archipelago during the temperate season; these organisms were morphologically identified and a systematic list including socioenvironmental attributes (SEA) was created. Species richness was used to assess the representativeness of the sampling and identify the distribution of species assemblages in relation to their SEA and environmental factors. In total, 31 species were described, representing 70% of the area’s potential diversity, and 97% of observations described species that had not yet been recorded in the area. Native, cryptogenic, and exotic species were found, including stinging and harvestable species. Groups with low, medium and high species richness were distributed heterogeneously, forming a spatial aggregation pattern. The results of this work suggest that the ESA has a highly diverse taxocene, with SEA and spatial aggregate structure relevant for integrative management and conservation of hydrozoans in natural protected areas.
Current Distribution and Conservation Issues of Aquatic Plant Species Protected under Habitats Directive in Lithuania
Authors: Sinkevičienė Zofija , Kamaitytė-Bukelskienė Liucija , Petrulaitis Lukas , Gudžinskas Zigmantas
Published: January 2023

The European Habitats Directive was adopted to halt the rapid loss of biodiversity and has become an important instrument for protecting biodiversity in the European Union. Three aquatic plant species protected under the European Habitats Directive have so far been found in Lithuania: Aldrovanda vesiculosa, Caldesia parnassifolia, and Najas flexilis. Our aim in this study was to evaluate the former and current distribution and the status of conservation of the target species. Screening for the above-mentioned protected aquatic plant species was performed in 73 natural lakes throughout Lithuania in 2019–2021. We confirmed extant populations of Aldrovanda vesiculosa in four lakes, Caldesia parnassifolia in two lakes, and Najas flexilis in four lakes in the northeastern part of the country. We studied Aldrovanda vesiculosa populations three times (2015, 2019, and 2022) in Lake Rūžas and once each in Lake Apvardai and Lake Dysnai (2020). The population density of Aldrovanda vesiculosa ranged from 193.4 ± 159.7 to 224.0 ± 211.0 individuals/m2, the mean length of plants ranged from 12.5 ± 2.1 to 14.3 ± 2.7 cm, and the mean number of apices ranged from 2.0 ± 0.7 to 2.2 ± 0.9 per individual. The habitat of Aldrovanda vesiculosa in Lake Rūžas covered an area of about 3 ha. The number of generative individuals of Caldesia parnassifolia widely varied between years in Lake Rūžas. All populations of Najas flexilis were small, although the potential habitats in the studied lakes cover relatively large areas. We propose designating all lakes with populations of Aldrovanda vesiculosa, Caldesia parnassifolia, and Najas flexilis as special areas of conservation, as well as developing and implementing action plans for the conservation of these species and their habitats.
Cave-Dwelling Populations of the Monstrous Rainfrog (Craugastor pelorus) from Mexico
Authors: Couto Henrique , Madeira Madalena Macara , Hernández Ordóñez Omar , Reynoso Víctor Hugo , Rosa Gonçalo M.
Published: January 2023

Amphibians are known cave dwellers, and a few anurans have shown to make exploratory or opportunistic use of subterranean environments. We report on the use of karst ecosystems and cavernicolous environments by the monstrous rainfrog Craugastor pelorus in Chiapas and Tabasco (Mexico). Individuals were found in crevices and wall depressions within the twilight zone of the cave, both during the day and at night. Although threatened by human activities and often severely understudied, caves are the last refugia for some endangered species. This report allows us to extend the known distribution of the species, increase our knowledge on a threatened species, and better understand the biodiversity and ecology of cave environments.
Floristic Homogenization and Differentiation under Deer Grazing in a Subalpine Zone in Central Japan
Authors: Nagaike Takuo
Published: January 2023

Changes of vegetation due to deer grazing may result in floristic homogenization or differentiation. The relationships between the changes caused by grazing are still being debated. Vascular plants and grazing by Cervus nippon were recorded in 2010 and 2018 in Betula forests and tall grassland communities in a subalpine zone, central Japan. Species composition differed significantly between vegetation types in both censuses. The α-diversity had declined significantly in both vegetation types. Metrics related to species replacement made a greater contribution to β-diversity than those related to nestedness in both vegetation types. A decrease of β-diversity based on incidence data from 2010 to 2018 in the Betula forests indicated that floristic homogenization had occurred; an increase of β-diversity based on abundance data from 2010 to 2018 in the grasslands indicated that floristic differentiation had occurred. Changes of α-diversity in both vegetation types and of β-diversity in the grasslands were significantly correlated with grazing intensity. These results showed that deterministic processes, which originally differed between the Betula forests and grasslands, would be the dominant causes of floristic changes under deer-grazing pressure.
Rare Variants of Dermatofibrosarcoma Protuberans: Clinical, Histologic, and Molecular Features and Diagnostic Pitfalls
Authors: Trinidad Celestine M. , Wangsiricharoen Sintawat , Prieto Victor G. , Aung Phyu P.
Published: January 2023

Dermatofibrosarcoma protuberans (DFSP) is a dermal malignant mesenchymal tumor. Most variants are associated with a high risk of local recurrence and a low risk of metastasis. The classic histomorphology of this tumor is made up of uniform, spindle-shaped cells, arranged in a storiform pattern. Tumor cells characteristically infiltrate the underlying subcutis in a honeycomb pattern. Less common variants of DFSP have been identified: myxoid, pigmented, myoid, granular cell, sclerosing, atrophic, and fibrosarcomatous. Only the fibrosarcomatous variant has been shown to differ significantly from classic DFSP in terms of clinical outcome; fibrosarcomatous DFSP has been shown to be associated with a greater risk of local recurrence and metastatic potential than classic DFSP. However, the other variants may pose diagnostic difficulty as they resemble other types of spindle cell neoplasms, especially in small biopsy specimens. This article reviews the clinical, histologic, and molecular features of DFSP variants, as well as possible pitfalls in their diagnosis and how to resolve them.
Atherosclerosis, Cardiovascular Disorders and COVID-19: Comorbid Pathogenesis
Authors: Makarova Yulia A. , Ryabkova Varvara A. , Salukhov Vladimir V. , Sagun Boris V. , Korovin Aleksandr E. , Churilov Leonid P.
Published: January 2023

The article describes how atherosclerosis and coronavirus disease 19 (COVID-19) may affect each other. The features of this comorbid pathogenesis at various levels (vascular, cellular and molecular) are considered. A bidirectional influence of these conditions is described: the presence of cardiovascular diseases affects different individuals’ susceptibility to viral infection. In turn, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can have a negative effect on the endothelium and cardiomyocytes, causing blood clotting, secretion of pro-inflammatory cytokines, and thus exacerbating the development of atherosclerosis. In addition to the established entry into cells via angiotensin-converting enzyme 2 (ACE2), other mechanisms of SARS-CoV-2 entry are currently under investigation, for example, through CD147. Pathogenesis of comorbidity can be determined by the influence of the virus on various links which are meaningful for atherogenesis: generation of oxidized forms of low-density lipoproteins (LDL), launch of a cytokine storm, damage to the endothelial glycocalyx, and mitochondrial injury. The transformation of a stable plaque into an unstable one plays an important role in the pathogenesis of atherosclerosis complications and can be triggered by COVID-19. The impact of SARS-CoV-2 on large vessels such as the aorta is more complex than previously thought considering its impact on vasa vasorum. Current information on the mutual influence of the medicines used in the treatment of atherosclerosis and acute COVID-19 is briefly summarized.
Radiologic Evaluation of Portosystemic Shunts in Humans and Small Animals: Review of the Literature with Clinical Case Reports
Authors: Umek Nejc , Plut Domen , Krofič Žel Martina , Domanjko Petrič Aleksandra
Published: January 2023

The portal venous system is a network of vessels that carry blood from the capillary beds of the major abdominal organs to the liver. During embryology, the portal venous system can develop aberrantly, leading to vascular connections between the portal and systemic venous circulation known as portosystemic shunts. The purpose of this comparative review with a few short representative case reports was to present the similarities and differences in portosystemic shunts in humans and small animals and their radiologic evaluation. Aberrant vascular connections between the portal and systemic venous circulation enable portal blood to bypass metabolism and detoxification in the liver, leading to significant clinical implications. Portosystemic shunts are very rare in humans, but these connections are much more common in small animals, affecting up to 0.6% of small animals. Portosystemic shunts can be congenital or acquired and are divided into intrahepatic and extrahepatic types. Because of its ability to accurately assess abdominal structures, large vessels, and their flow dynamics without anesthesia, ultrasonography has become the first imaging modality employed for the diagnostic evaluation of portosystemic shunts in both humans and small animals. This is usually followed by contrast-enhanced computed tomographic angiography in order to better define the exact shunt anatomy and to plan treatment. It is important to understand the embryology, anatomy, pathology, and pathophysiology of portosystemic shunts in order to understand the findings of radiologic imaging and to initiate appropriate treatment.
Large-Vessel Giant Cell Arteritis following COVID-19—What Can HLA Typing Reveal?
Authors: Stojanovic Maja , Barac Aleksandra , Petkovic Ana , Vojvodic Nikola , Odalovic Strahinja , Andric Zorana , Miskovic Rada , Jovanovic Dragana , Dimic-Janjic Sanja , Dragasevic Sanja , Raskovic Sanvila , Stjepanovic Mihailo I.
Published: January 2023

Giant cell arteritis (GCA) is an immune-mediated vasculitis that affects large arteries. It has been hypothesized that viruses may trigger inflammation within the vessel walls. Genetic studies on human leukocyte antigens (HLAs) have previously reported HLA-DRB1*04 as a susceptible allele for GCA and HLA-DRB1*15 as a protective allele for GCA. Here, we discuss the clinical presentation, laboratory findings, HLA class I and class II analysis results, and management of patients with extracranial large-vessel (LV) GCA, detected at least six weeks after recovery from COVID-19. This case series encompassed three patients with LV-GCA (two males and a female with an age range of 63–69 years) whose leading clinical presentation included the presence of constitutional symptoms and significantly elevated inflammatory markers. The diagnosis of LV-GCA was confirmed by CT angiography and FDG-PET/CT, revealing inflammation in the large vessels. All were treated with corticosteroids, while two received adjunctive therapy. By analyzing HLA profiles, we found no presence of the susceptible HLA-DRB1*04 allele, while the HLA-DRB1*15 allele was detected in two patients. In conclusion, LV-GCA may be triggered by COVID-19. We highlight the importance of the early identification of LV-GCA following SARS-CoV-2 infection, which may be delayed due to the overlapping clinical features of GCA and COVID-19. The prompt initiation of therapy is necessary in order to avoid severe vascular complications. Future studies will better define the role of specific HLA alleles in patients who developed GCA following COVID-19.
Prediction of Wilms’ Tumor Susceptibility to Preoperative Chemotherapy Using a Novel Computer-Aided Prediction System
Authors: Sharaby Israa , Alksas Ahmed , Nashat Ahmed , Balaha Hossam Magdy , Shehata Mohamed , Gayhart Mallorie , Mahmoud Ali , Ghazal Mohammed , Khalil Ashraf , Abouelkheir Rasha T. , Elmahdy Ahmed , Abdelhalim Ahmed , Mosbah Ahmed , El-Baz Ayman
Published: January 2023

Wilms’ tumor, the most prevalent renal tumor in children, is known for its aggressive prognosis and recurrence. Treatment of Wilms’ tumor is multimodal, including surgery, chemotherapy, and occasionally, radiation therapy. Preoperative chemotherapy is used routinely in European studies and in select indications in North American trials. The objective of this study was to build a novel computer-aided prediction system for preoperative chemotherapy response in Wilms’ tumors. A total of 63 patients (age range: 6 months–14 years) were included in this study, after receiving their guardians’ informed consent. We incorporated contrast-enhanced computed tomography imaging to extract the texture, shape, and functionality-based features from Wilms’ tumors before chemotherapy. The proposed system consists of six steps: (i) delineate the tumors’ images across the three contrast phases; (ii) characterize the texture of the tumors using first- and second-order textural features; (iii) extract the shape features by applying a parametric spherical harmonics model, sphericity, and elongation; (iv) capture the intensity changes across the contrast phases to describe the tumors’ functionality; (v) apply features fusion based on the extracted features; and (vi) determine the final prediction as responsive or non-responsive via a tuned support vector machine classifier. The system achieved an overall accuracy of 95.24%, with 95.65% sensitivity and 94.12% specificity. Using the support vector machine along with the integrated features led to superior results compared with other classification models. This study integrates novel imaging markers with a machine learning classification model to make early predictions about how a Wilms’ tumor will respond to preoperative chemotherapy. This can lead to personalized management plans for Wilms’ tumors.
Changes in Clinical Manifestations Due to AFLD Retyping Based on the New MAFLD Criteria: An Observational Study Based on the National Inpatient Sample Database
Authors: Feng Xiaoshan , Xuan Ruirui , Dong Yingchun , Wu Xiaoqin , Cheng Yiping , Yuan Zinuo , Dong Hang , Han Junming , Zhong Fang , Zhao Jiajun , Fan Xiude
Published: January 2023

(1) Background: As the introduction of “positive” diagnostic criteria for metabolic dysfunction-associated fatty liver disease (MAFLD) does not exclude alcohol consumption, some patients originally diagnosed with alcoholic fatty liver disease (AFLD) may be diagnosed with dual- etiology fatty liver disease (AFLD&MAFLD), which requires us to urgently explore the impact of the changes in this classification of AFLD on clinical manifestations. (2) Methods: Utilizing data from the Nationwide Inpatient Sample database 2016–2018, a total of 9269 participants with AFLD were selected. With the definition of MAFLD, these patients were further categorized into two groups: single AFLD and AFLD&MAFLD. The primary outcome was the risk of comorbidities and organ failures. The secondary outcomes were the length of stay, total charges, and in-hospital all-cause mortality. (3) Results: The patients with AFLD&MAFLD were older, were predominantly male, and had more comorbidities and organ failures compared to the patients with AFLD. These comorbidities included coronary atherosclerosis, myocardial infarction, cerebrovascular disease, arrhythmia, asthma, chronic obstructive pulmonary disease, and chronic kidney disease (all p values < 0.05). The patients with AFLD&MAFLD were more likely to develop acute and chronic heart and/or kidney failures than those with single AFLD (all p < 0.05). The length of stay and total charges of the patients in the AFLD&MAFLD group were greater than the single AFLD group (p = 0.029 and p < 0.001, respectively). No significant difference in all-cause mortality was observed. (4) Conclusions: The patients with AFLD&MAFLD have more comorbidities and organ failures, longer hospital stays, and higher hospitalization costs than the patients with single AFLD. Hence, patients with dual-etiology fatty liver disease deserve more attention from clinical staff during treatment.
Partially Dedifferentiated Primitive Malignant Melanoma with Pseudo-Angiomatous Features: A Case Report with Review of the Literature
Authors: Ambrogio Francesca , Colagrande Anna , Cascardi Eliano , Grandolfo Mauro , Filotico Raffaele , Foti Caterina , Lupo Carmelo , Casatta Nadia , Ingravallo Giuseppe , Cazzato Gerardo
Published: January 2023

Malignant melanoma (MM) is traditionally known as the “great mime” of human pathology, as it is potentially capable of imitating the most disparate neoplasms. It is known that in addition to the more classic histotypes of MM, there are also rare forms, including angiomatoid MM. Similarly, it has been amply demonstrated in the literature that MM is capable of dedifferentiating, losing melanocytic lineage markers, constituting a diagnostic challenge for the pathologist. Although 5 cases of primary angiomatoid MM have been described in the literature, to the best of our knowledge, no cases of dedifferentiated melanoma with pseudo-angiomatoid aspects have ever been described. In this paper, we present a very rare case of partially dedifferentiated MM in which the most dedifferentiated component lost melanocytic lineage immunohistochemical markers and assumed a pseudo-angiomatous morphology. Given the rarity of the case, we carried out a literature review of similar cases described, trying to draw new future perspectives not only about this particular variant of MM but also about the widest field of dedifferentiation/undifferentiation of MM.
Association of Fatty Liver Index with Incident Diabetes Risk in Patients Initiating Statin–Therapy: A 6-Year Retrospective Study
Authors: Anastasiou Georgia , Liberopoulos Evangelos , Petkou Ermioni , Koutsogianni Amalia Despoina , Adamidis Petros Spyridwnas , Liamis George , Ntzani Evangelia , Barkas Fotios
Published: January 2023

Background: Statins are associated with new-onset type 2 diabetes (T2D), mainly in patients with metabolic syndrome (MetS). The fatty liver index (FLI) is used as a prognostic score for the diagnosis of non-alcoholic fatty liver disease (NAFLD), which is common in patients with MetS. We aimed to investigate the association of FLI with new-onset T2D in patients initiating statin therapy. Methods: A retrospective observational study including 1241 individuals with dyslipidemia and followed up for ≥3 years. Patients with T2D and those receiving lipid-lowering treatment at the baseline visit were excluded. Models with clinical and laboratory parameters were used to assess the association of FLI with incident T2D. Results: Among the 882 eligible subjects, 11% developed T2D during the follow-up (6 years; IQR: 4–10 years). After adjusting for sex, age and MetS parameters, a multivariate analysis revealed that age (HR:1.05; 95%CI: 1.01–1.09, p < 0.05), fasting plasma glucose (HR: 1.09; 95%CI: 1.06–1.13, p < 0.001) and FLI (HR: 1.02; 95%CI: 1.01–1.04, p < 0.01) were independently associated with T2D risk. The subjects with probable NAFLD (FLI ≥ 60) had a three-fold increased T2D risk compared with the subjects with FLI < 60 (HR: 3.14; 95%CI: 1.50–6.59, p = 0.001). A ROC curve analysis showed that FLI had a significant, although poor, predictive value for assessing T2D risk (C-Statistic: 0.67; 95%CI: 0.58–0.77, p = 0.001). Higher FLI values were associated with reduced T2D-free survival (log-rank = 15.46, p < 0.001). Conclusions: FLI is significantly and independently associated with new-onset T2D risk in patients initiating statin therapy.
A Male Subject with Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency Which Was Diagnosed at 31 Years Old due to Infertility
Authors: Kaneto Hideaki , Isobe Hayato , Sanada Junpei , Tatsumi Fuminori , Kimura Tomohiko , Shimoda Masashi , Nakanishi Shuhei , Kaku Kohei , Mune Tomoatsu
Published: January 2023

Introduction: Congenital adrenal hyperplasia is caused by deficiencies in a number of enzymes involved in hormone biosynthesis in the adrenal glands or sexual glands. Adrenocorticotropic hormone (ACTH) secretion is enhanced by decreased cortisol production, leading to adrenal hyperplasia. The frequency of 21-hydroxylase deficiency (21-OHD) was the highest among congenital hyperplasias, and in 1989 it became one of the target diseases for newborn screening in Japan. Case presentation: A 31-year-old Japanese male visited our institution due to infertility. On admission, his height was 151.7 cm (average ± SD in the same age, sex and population: 172.1 ± 6.1 cm). It was noted that his height had not changed since he was ten years old, and that pubic hair was observed when he was 7 years old. He had azoospermia and his gonadotropin level was low. He had low levels of both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) but high levels of free testosterone. He had a low cortisol level and high ACTH level. Abdominal computed tomography (CT) showed swelling of bilateral adrenal glands, although morphology was normal. Based on these findings, he was diagnosed with primary adrenal insufficiency and admitted to our institution. His height had not changed since he was ten years old. In addition, pubic hair was observed when he was 7 years old. His sexual desire was decreased, although he had no general malaise or fatigue. He did not have pigmentation of the skin, genital atrophy or defluxion of pubic hair, although his body hair was relatively thin. In endocrinology markers, ACTH level was high (172.2 pg/mL) (reference range: 7.2–63.3 pg/mL), although his cortisol level was 6.9 μg/dL (4.5–21.1 μg/dL). These data suggest that he suffered from primary adrenal insufficiency. LH and FSH levels were both low, but free testosterone and estradiol levels were high. These data excluded the possibility of central hypogonadism. Furthermore, the level of 17a-hydroxyprogesterone, a substrate of 21-hydroxylase, and the level of pregnanetriol, a metabolite of progesterone in urine, were both markedly high. Based on these findings, we ultimately diagnosed this patient with 21-hydroxylase deficiency. Conclusions: We experienced a case of congenital adrenal hyperplasia due to 21-hydroxylase deficiency which was diagnosed in a 31-year-old male with infertility. Therefore, the possibility of 21-hydroxylase deficiency should be borne in mind in subjects with infertility who were born before 1989 and who had not undergone newborn screening for this disease.
Feasibility of Dynamic Inhaled Gas MRI-Based Measurements Using Acceleration Combined with the Stretched Exponential Model
Authors: Sembhi Ramanpreet , Ranota Tuneesh , Fox Matthew , Couch Marcus , Li Tao , Ball Iain , Ouriadov Alexei
Published: January 2023

Dynamic inhaled gas (3He/129Xe/19F) MRI permits the acquisition of regional fractional-ventilation which is useful for detecting gas-trapping in lung-diseases such as lung fibrosis and COPD. Deninger’s approach used for analyzing the wash-out data can be substituted with the stretched-exponential-model (SEM) because signal-intensity is attenuated as a function of wash-out-breath in 19F lung imaging. Thirteen normal-rats were studied using 3He/129Xe and 19F MRI and the ventilation measurements were performed using two 3T clinical-scanners. Two Cartesian-sampling-schemes (Fast-Gradient-Recalled-Echo/X-Centric) were used to test the proposed method. The fully sampled dynamic wash-out images were retrospectively under-sampled (acceleration-factors (AF) of 10/14) using a varying-sampling-pattern in the wash-out direction. Mean fractional-ventilation maps using Deninger’s and SEM-based approaches were generated. The mean fractional-ventilation-values generated for the fully sampled k-space case using the Deninger method were not significantly different from other fractional-ventilation-values generated for the non-accelerated/accelerated data using both Deninger and SEM methods (p > 0.05 for all cases/gases). We demonstrated the feasibility of the SEM-based approach using retrospective under-sampling, mimicking AF = 10/14 in a small-animal-cohort from the previously reported dynamic-lung studies. A pixel-by-pixel comparison of the Deninger-derived and SEM-derived fractional-ventilation-estimates obtained for AF = 10/14 (≤16% difference) has confirmed that even at AF = 14, the accuracy of the estimates is high enough to consider this method for prospective measurements.
Disturbance Interval Observer-Based Robust Constrained Control for Unmanned Aerial Vehicle Path Following
Authors: Song Yaping , Yong Kenan , Wang Xiaolong
Published: January 2023

This work presents a robust constrained path-following control scheme for the unmanned aerial vehicle (UAV) under wind disturbances. Through appointing the projection from the UAV to the path, the Serret–Frenet frame is introduced to reduce the complexity of the path-following problem. Specifically, the disturbance interval observer is employed to generate the interval of the wind disturbances. Then, the path-following control design is presented based on the dynamic surface control technique, and the auxiliary system is adopted to deal with the command limitation during the design process. Accordingly, the stability of the closed-loop system is analyzed. The effectiveness of the developed control scheme is demonstrated using numerical simulations.
Object Recognition of a GCP Design in UAS Imagery Using Deep Learning and Image Processing—Proof of Concept Study
Authors: Becker Denise , Klonowski Jörg
Published: January 2023

Image-based unmanned aircraft systems (UASs) are used in a variety of geodetic applications. Precise 3D terrain surface mapping requires ground control points (GCPs) for scaling and (indirect) georeferencing. In image analysis software (e.g., Agisoft Metashape), the images can be generated to a 3D point cloud using Structure-from-Motion (SfM). In general, the conventional GCP design for UAS flights is a checkerboard pattern, which is provided in the software and used for automatic marker detection in each image. When changing the pattern, manual work would be required by picking the GCP individually by hand. To increase the level of automation in the evaluation, this article aims to present a workflow that automatically detects a new edge-based GCP design pattern in the images, calculates their center points, and provides this information to the SfM software. Using the proposed workflow based on deep learning (DL) and image processing, the quality of the resulting 3D model can be equated to the result with GCP center points picked by human evaluator. Consequently, the workload can be accelerated with this approach.