bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacological Efficacy and Gastrointestinal Safety of Different Aspirin Formulations for Cardiovascular Prevention: A Narrative Review
Authors: Clerici Bianca , Cattaneo Marco
Published: March 2023

Aspirin inhibits platelet function by irreversibly inhibiting the synthesis of thromboxane A2 (TxA2). Aspirin, at low doses, is widely used for cardiovascular prevention. Gastrointestinal discomfort, mucosal erosions/ulcerations and bleeding are frequent complications of chronic treatment. To reduce these adverse effects, different formulations of aspirin have been developed, including enteric-coated (EC) aspirin, the most widely used aspirin formulation. However, EC aspirin is less effective than plain aspirin in inhibiting TxA2 production, especially in subjects with high body weight. The inadequate pharmacological efficacy of EC aspirin is mirrored by lower protection from cardiovascular events in subjects weighing >70 kg. Endoscopic studies showed that EC aspirin causes fewer erosions of the gastric mucosa compared to plain aspirin (which is absorbed in the stomach) but causes mucosal erosions in the small intestine, where it is absorbed. Several studies demonstrated that EC aspirin does not reduce the incidence of clinically relevant gastrointestinal ulceration and bleeding. Similar results were found for buffered aspirin. Although interesting, the results of experiments on the phospholipid-aspirin complex PL2200 are still preliminary. Considering its favorable pharmacological profile, plain aspirin should be the preferred formulation to be used for cardiovascular prevention.
A Refined Single Cell Landscape of Haematopoiesis in the Mouse Foetal Liver
Authors: Ceccacci Elena , Villa Emanuela , Santoro Fabio , Minucci Saverio , Ruhrberg Christiana , Fantin Alessandro
Published: March 2023

During prenatal life, the foetal liver is colonised by several waves of haematopoietic progenitors to act as the main haematopoietic organ. Single cell (sc) RNA-seq has been used to identify foetal liver cell types via their transcriptomic signature and to compare gene expression patterns as haematopoietic development proceeds. To obtain a refined single cell landscape of haematopoiesis in the foetal liver, we have generated a scRNA-seq dataset from a whole mouse E12.5 liver that includes a larger number of cells than prior datasets at this stage and was obtained without cell type preselection to include all liver cell populations. We combined mining of this dataset with that of previously published datasets at other developmental stages to follow transcriptional dynamics as well as the cell cycle state of developing haematopoietic lineages. Our findings corroborate several prior reports on the timing of liver colonisation by haematopoietic progenitors and the emergence of differentiated lineages and provide further molecular characterisation of each cell population. Extending these findings, we demonstrate the existence of a foetal intermediate haemoglobin profile in the mouse, similar to that previously identified in humans, and a previously unidentified population of primitive erythroid cells in the foetal liver.
Efficient Approach to Color Image Segmentation Based on Multilevel Thresholding Using EMO Algorithm by Considering Spatial Contextual Information
Authors: Rangu Srikanth , Veramalla Rajagopal , Salkuti Surender Reddy , Kalagadda Bikshalu
Published: March 2023

The process of image segmentation is partitioning an image into its constituent parts and is a significant approach for extracting interesting features from images. Over a couple of decades, many efficient image segmentation approaches have been formulated for various applications. Still, it is a challenging and complex issue, especially for color image segmentation. To moderate this difficulty, a novel multilevel thresholding approach is proposed in this paper based on the electromagnetism optimization (EMO) technique with an energy curve, named multilevel thresholding based on EMO and energy curve (MTEMOE). To compute the optimized threshold values, Otsu’s variance and Kapur’s entropy are deployed as fitness functions; both values should be maximized to locate optimal threshold values. In both Kapur’s and Otsu’s methods, the pixels of an image are classified into different classes based on the threshold level selected on the histogram. Optimal threshold levels give higher efficiency of segmentation; the EMO technique is used to find optimal thresholds in this research. The methods based on an image’s histograms do not possess the spatial contextual information for finding the optimal threshold levels. To abolish this deficiency an energy curve is used instead of the histogram and this curve can establish the spatial relationship of pixels with their neighbor pixels. To study the experimental results of the proposed scheme, several color benchmark images are considered at various threshold levels and compared with other meta-heuristic algorithms: multi-verse optimization, whale optimization algorithm, and so on. The investigational results are illustrated in terms of mean square error, peak signal-to-noise ratio, the mean value of fitness reach, feature similarity, structural similarity, variation of information, and probability rand index. The results reveal that the proposed MTEMOE approach overtops other state-of-the-art algorithms to solve engineering problems in various fields.
COVID-19 Associated Pulmonary Aspergillosis in Patients on Extracorporeal Membrane Oxygenation Treatment—A Retrospective Study
Authors: Nuh Ali , Ramadan Newara , Nwankwo Lisa , Donovan Jackie , Patel Brijesh , Shah Anand , Desai Sujal R. , Armstrong-James Darius
Published: March 2023

Background: The incidence and outcome of pulmonary aspergillosis in coronavirus disease (COVID-19) patients on extracorporeal membrane oxygenation (ECMO) are unknown and have not been fully addressed. We investigated the incidence, risk factors and outcome of pulmonary aspergillosis in COVID-19 ECMO patients. In addition, the diagnostic utility of bronchoalveolar lavage fluid and CT scans in this setting were assessed. Methods: We conducted a retrospective study on incidence and outcome of pulmonary aspergillosis in COVID-19 ECMO patients by reviewing clinical, radiological, and mycological evidence. These patients were admitted to a tertiary cardiothoracic centre during the early COVID-19 surge between March 2020 and January 2021. Results and measurements: The study included 88 predominantly male COVID-19 ECMO patients with a median age and a BMI of 48 years and 32 kg/m2, respectively. Pulmonary aspergillosis incidence was 10% and was associated with very high mortality. Patients with an Aspergillus infection were almost eight times more likely to die compared with those without infection in multivariate analysis (OR 7.81, 95% CI: 1.20–50.68). BALF GM correlated well with culture results, with a Kappa value of 0.8 (95% CI: 0.6, 1.0). However, serum galactomannan (GM) and serum (1–3)-β-D-glucan (BDG) lacked sensitivity. Thoracic computed tomography (CT) diagnostic utility was also inconclusive, showing nonspecific ground glass opacities in almost all patients. Conclusions: In COVID-19 ECMO patients, pulmonary aspergillosis incidence was 10% and associated with very high mortality. Our results support the role of BALF in the diagnosis of pulmonary aspergillosis in COVID-19 ECMO patients. However, the diagnostic utility of BDG, serum GM, and CT scans is unclear.
New Horizons or Business as Usual? New Zealand’s Medico-Legal Response to Digital Harm
Authors: Kelly Olivia
Published: March 2023

A socio-legal commentary, this article examines the emerging issue of digital harm in New Zealand’s health settings. There are recent cases, and an increasing number of them, demonstrating the medico-legal response to various forms of digital harm. Of these, several representative cases are considered in order to identify features of digital harm within the health context. The article questions whether this is a new type of harm, enabled by the creation of new technologies, or simply a different manifestation of conventional unprofessional or unethical behaviour. The article considers whether the existing medico-legal framework can appropriately respond to this harm and whether new legal or policy tools are required. The cases suggest that the rights and disciplinary systems in place can adequately deal with digital harm within their existing scopes, particularly when individuals have been harmed. However, gaps in the legal framework are identified, with particular reference to the actions of unregistered providers and harm to professions. Further, a future challenge for the system may be the response to COVID-19 vaccine denial and misinformation. As the legal response to digital harm in the health context is a relatively unexamined area of research, this work may guide future research.
Wood Ash as Sustainable Alternative Raw Material for the Production of Concrete—A Review
Authors: Teker Ercan Ece Ezgi , Andreas Lale , Cwirzen Andrzej , Habermehl-Cwirzen Karin
Published: March 2023

Different ecological binders have been used to minimize the negative effects of cement production and use on the environment. Wood ash is one of these alternative binders, and there has been increasing research related to this topic recently. The wood ash utilized in the literature primarily originates from power plants and local bakeries, and predominantly wood fly ash is used. This review paper examines the use of wood ash as an ecological binder in two different applications: as a cement replacement and as an alkali-activated material. Studies have shown that while increased wood ash content in concrete and mortars can have negative effects on strength and durability, it is still a promising and developable material. Depending on the chemical composition of the wood ash, the strength and durability properties of concrete might be slightly improved by utilizing wood ash as a replacement for cement, with an optimal replacement level of 10–20%. However, there is a need for more research regarding the effects of wood ash on the durability of cement-based materials and its use in alkali-activated materials. Overall, this review provides a comprehensive overview of the properties of wood ash and its potential applications in conventional concrete and mortars, as well as in alkali-activated materials.
π-Shape ESD Protection Design for Multi-Gbps High-Speed Circuits in CMOS Technology
Authors: Chang Chun-Rong , Dai Zih-Jyun , Lin Chun-Yu
Published: March 2023

CMOS integrated circuits are vulnerable to electrostatic discharge (ESD); therefore, ESD protection circuits are needed. On-chip ESD protection is important for both component-level and system-level ESD protection. In this work, on-chip ESD protection circuits for multi-Gbps high-speed applications are studied. π-shaped ESD protection circuit structures realized by staked diodes with an embedded silicon-controlled rectifier (SCR) and resistor-triggered SCR are proposed. These test circuits are fabricated in CMOS technology, and the proposed designs have been proven to have better ESD robustness and performance in high-speed applications.
Experimental Analysis and Neural Network Modeling of the Rheological Behavior of Xanthan Gum and Its Derivatives
Authors: Yahoum Madiha Melha , Toumi Selma , Hentabli Salma , Tahraoui Hichem , Lefnaoui Sonia , Hadjsadok Abdelkader , Amrane Abdeltif , Kebir Mohammed , Moula Nassim , Assadi Amin Aymen , Zhang Jie , Mouni Lotfi
Published: March 2023

The main objective of this study was to create a mathematical tool that could be used with experimental data to predict the rheological flow behavior of functionalized xanthan gum according to the types of chemical groups grafted onto its backbone. Different rheological and physicochemical analyses were applied to assess six derivatives synthesized via the etherification of xanthan gum by hydrophobic benzylation with benzyl chloride and carboxymethylation with monochloroacetic acid at three (regent/polymer) ratios R equal to 2.4 and 6. Results from the FTIR study verified that xanthan gum had been modified. The degree of substitution (DS) values varying between 0.2 and 2.9 for carboxymethylxanthan gum derivatives were found to be higher than that of hydrophobically modified benzyl xanthan gum for which the DS ranged from 0.5 to 1. The molecular weights of all the derivatives were found to be less than that of xanthan gum for the two types of derivatives, decreasing further as the degree of substitution (DS) increased. However, the benzyl xanthan gum derivatives presented higher molecular weights varying between 1,373,146 (g/mol) and 1,262,227 (g/mol) than carboxymethylxanthan gum derivatives (1,326,722–1,015,544) (g/mol). A shear-thinning behavior was observed in the derivatives, and the derivatives’ viscosity was found to decrease with increasing DS. The second objective of this research was to create an ANN model to predict one of the rheological properties (the apparent viscosity). The significance of the ANN model (R2 = 0.99998 and MSE = 5.95 × 10−3) was validated by comparing experimental results with the predicted ones. The results showed that the model was an efficient tool for predicting rheological flow behavior.
Effect of Asymmetric Fins on Thermal Performance of Phase Change Material-Based Thermal Energy Storage Unit
Authors: Shaban Muhammad , Khan Talha Irfan , Anwar Muhammad , Alzaid Meshal , Alanazi Rakan
Published: March 2023

Phase change material (PCM)-based thermal energy storage units (TESU) have very low thermal conductivity that compromise their charging and discharging rate. The present study focuses on an enhancement in charging rate as well as an increase in the uniformity of the melting rate. A rectangular cavity consisting of two horizontal partial fins is studied. The horizontal partial fins are placed symmetrically in a PCM-based TESU. In the current work, the melting rate of PCM was enhanced using asymmetric arrangement while keeping all other parameters the same, thus showing the positive effect of asymmetric configuration in such storage systems. The position and the pitch of each fin is optimized to improve heat transfer characteristics of the TESU. The numerical investigation of the problem is performed. TESU with asymmetrically placed fins show better performance in terms of higher charging rate as well as uniformity of the charging rate. The asymmetric placement of the fins suggested by present study increased the charging rate by 74.3% on average as compared to the symmetrically placed fins in the storage system. The charging rate uniformity is improved by 43.7%. The asymmetric fin’s placement conserved the convection strength for a longer melting duration and so increased the Nusselt number by 80.2% as compared to the symmetrically placed fins. Thus, it can be concluded that the performance of asymmetric fins is better in the charging of PCMs than the symmetrically placed fins in a PCM-based TESU.
Long-Term Oxidation of Zirconium Alloy in Simulated Nuclear Reactor Primary Coolant—Experiments and Modeling
Authors: Betova Iva , Bojinov Martin , Karastoyanov Vasil
Published: March 2023

Oxidation of Zr-1%Nb fuel cladding alloy in simulated primary coolant of a pressurized water nuclear reactor is followed by in-situ electrochemical impedance spectroscopy. In-depth composition and thickness of the oxide are estimated by ex-situ analytical techniques. A kinetic model of the oxidation process featuring interfacial reactions of metal oxidation and water reduction, as well as electron and ion transport through the oxide governed by diffusion-migration, is parameterized by quantitative comparison to impedance data. The effects of compressive stress on diffusion and ionic space charge on migration of ionic point defects are introduced to rationalize the dependence of transport parameters on thickness (or oxidation time). The influence of ex-situ and in-situ hydrogen charging on kinetic and transport parameters is also studied.
Properties of Coatings Based on Calcium Phosphate and Their Effect on Cytocompatibility and Bioactivity of Titanium Nickelide
Authors: Marchenko Ekaterina S. , Baigonakova Gulsharat A. , Dubovikov Kirill M. , Kokorev Oleg V. , Gordienko Ivan I. , Chudinova Ekaterina A.
Published: March 2023

Coatings based on calcium phosphate with thicknesses of 0.5 and 2 μm were obtained by high-frequency magnetron sputtering on NiTi substrates in an argon atmosphere. The coating was characterized using X-ray diffraction, scanning electron microscopy, atomic force microscopy, and in vitro cytocompatibility and bioactivity studies. A biphasic coating of tricalcium phosphate (Ca3(PO4)2) and hydroxyapatite (Ca10(PO4)6(OH)2) with a 100% degree of crystallinity was formed on the surface. The layer enriched in calcium, phosphorus, and oxygen was observed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Scanning electron microscopy showed that the surface structure is homogeneous without visible defects. The 2 µm thick coating obtained by sputtering with a deposition time of 4 h and a deposition rate of 0.43 µm/h is uniform, contains the highest amount of the calcium phosphate phase, and is most suitable for the faster growth of cells and accelerated formation of apatite layers. Samples with calcium phosphate coatings do not cause hemolysis and have a low cytotoxicity index. The results of immersion in a solution simulating body fluid show that NiTi with the biphasic coating promotes apatite growth, which is beneficial for biological activity.
A Study on Drilling of CFRP/Ti Stacks: Temperature Field and Thermal Damage of the Interface Region
Authors: Chen Chen , Wang Aixu , Zheng Zhi , Zhao Qing , Shi Zhanli , Bao Yongjie
Published: March 2023

Carbon fiber reinforced plastics (CFRP)/titanium alloy (Ti) stacks have been widely used in aviation field due to the superior mechanical properties. During integrated drilling of CFRP/Ti stacks, serious damage occurs in the CFRP layer because of the disparate properties of two stack components. Heat accumulation and thermal induced damage are typical and critical issue during drilling stacks, especially in the interface region. In this study, in order to deeply analyze the thermal influence of the interface region, a numerical model based on the finite difference method is developed to predict the three-dimensional drilling temperature field. Experiments with accurate measurement point are conducted to valid the rational of temperature prediction model. The results confirm that the temperature distributions predicted by numerical study have good agreements with the experimental results and the maximum error is about 10.3%. Furtherly, based on the drilling experiments, it can be found that thermal damage induced by cutting heat occurs as discoloration rings around the hole which could cause the elastic modulus of resin matrix decrease. An empirical model of thermal damage with maximum drilling temperature of the interface region are developed with the correlation of R2 = 0.97. The findings point out that as the maximum drilling temperature exceeds 410 °C, serious thermal damage could occur in the resin matrix of CFRP layer.
Research on Postcuring Parameters Effect on the Properties of Fiberglass-Reinforced Silicone Resin Coil Bobbin
Authors: He Hongmei , He Qiqi , Gao Hongchen , Hu Wei , Xue Song
Published: March 2023

With the growing demand for insulation parts in extreme service environments, such as nuclear power, aviation, and other related fields, fiberglass-reinforced silicone resin (FRSR) has become a popular choice due to its exceptional physical and chemical properties in high-temperature and electromagnetic working environments. To enhance the performance of FRSR molded parts that can adapt to more demanding extreme environments, the oven postcuring process parameters on thermal stability and mechanical properties of the bobbin were investigated. The curing behavior of FRSR was analyzed by using thermogravimetric analysis (TGA) and the differential scanning calorimetry (DSC) method, and the bobbins were manufactured based on the testing results. Subsequently, the bobbins were oven postcured at different conditions, and the heat resistance and mechanical properties were analyzed by TGA and tensile tests. The results revealed that the tensile strength of the bobbin increased by 122%, and the weight loss decreased by 0.79% at 350 °C after baking at 175 °C for 24 h. The optimal process parameters for producing bobbins to meet the criteria of nuclear installations were determined to be a molding temperature of 120 °C, molding pressure of 50 MPa, pressure holding time of 3 min, oven postcuring temperature of 175 °C, and postcuring time of 24 h. The molded products have passed the thermal aging performance test of nuclear power units.
Highly Stable Pt-Based Oxygen Reduction Electrocatalysts toward Practical Fuel Cells: Progress and Perspectives
Authors: Chen Miao-Ying , Li Yuan , Wu Hao-Ran , Lu Bang-An , Zhang Jia-Nan
Published: March 2023

The high cost and poor reliability of cathodic electrocatalysts for the oxygen reduction reaction (ORR), which requires significant amounts of expensive and scarce platinum, obstructs the broad applications of proton exchange membrane fuel cells (PEMFCs). The principles of ORR and the reasons for the poor stability of Pt-based catalysts are reviewed. Moreover, this paper discusses and categorizes the strategies for enhancing the stability of Pt-based catalysts in fuel cells. More importantly, it highlights the recent progress of Pt-based stability toward ORR, including surface-doping, intermetallic structures, 1D/2D structures, rational design of support, etc. Finally, for atomic-level in-depth information on ORR catalysts in fuel cells, potential perspectives are suggested, such as large-scale preparation, advanced interpretation techniques, and advanced simulation. This review aims to provide valuable insights into the fundamental science and technical engineering for practical Pt-based ORR electrocatalysts in fuel cells.
Substrate-Induced Changes on the Optical Properties of Single-Layer WS2
Authors: Araujo F. D. V. , Silva F. W. N. , Zhang T. , Zhou C. , Lin Zhong , Perea-Lopez Nestor , Rodrigues Samuel F. , Terrones Mauricio , Souza Filho Antônio Gomes , Alencar R. S. , Viana Bartolomeu C.
Published: March 2023

Among the most studied semiconducting transition metal dichalcogenides (TMDCs), WS2 showed several advantages in comparison to their counterparts, such as a higher quantum yield, which is an important feature for quantum emission and lasing purposes. We studied transferred monolayers of WS2 on a drilled Si3N4 substrate in order to have insights about on how such heterostructure behaves from the Raman and photoluminescence (PL) measurements point of view. Our experimental findings showed that the Si3N4 substrate influences the optical properties of single-layer WS2. Beyond that, seeking to shed light on the causes of the PL quenching observed experimentally, we developed density functional theory (DFT) based calculations to study the thermodynamic stability of the heterojunction through quantum molecular dynamics (QMD) simulations as well as the electronic alignment of the energy levels in both materials. Our analysis showed that along with strain, a charge transfer mechanism plays an important role for the PL decrease.
Effect of Magnetite Concrete on Splitting Tensile Strength and Gamma Ray Shielding Performance Exposed to Repeated Heating at High Temperature
Authors: Huang Xinyun , Chen Zhenfu , Tao Qiuwang , Xie Liping , Jin Dan , Wu Dan
Published: March 2023

Radiation shielding concrete is one of the most used materials in the construction of nuclear power plants and will be subjected to high temperatures for a long time during its service life. This study aims to investigate deterioration of radiation shielding concrete with multiple heating at different temperatures. A microwave oven was used as a heating apparatus to simulate irradiation, and 200, 300, and 400 °C were selected as experimental cycle temperatures. The apparent characteristics, mass loss, splitting tensile strength, and gamma ray shielding properties of the commonly used magnetite shielding concrete were investigated. The results showed that the splitting tensile strength and gamma shielding performance of concrete were dramatically reduced at first heating. Then, as the heating times increased, the splitting tensile strength and gamma shielding properties of the concrete continued to deteriorate, and the higher the increase in heating temperature, the more severe the deterioration of the concrete. During the service period of radiation shielded concrete, the magnitude of temperature under the service conditions will affect the deterioration degree of concrete, and the continuous change of temperature will continuously lead to the deterioration of concrete.
Suppressing Viscous Fingering in Porous Media with Wetting Gradient
Authors: Wang Xiongsheng , Yin Cuicui , Wang Juan , Zheng Kaihong , Zhang Zhengrong , Tian Zhuo , Xiong Yongnan
Published: March 2023

The viscous fingering phenomenon often occurs when a low-viscosity fluid displaces a high-viscosity fluid in a homogeneous porous media, which is an undesirable displacement process in many engineering applications. The influence of wetting gradient on this process has been studied over a wide range of capillary numbers (7.5 × 10−6 to 1.8 × 10−4), viscosity ratios (0.0025 to 0.04), and porosities (0.48 to 0.68), employing the lattice Boltzmann method. Our results demonstrate that the flow front stability can be improved by the gradual increase in wettability of the porous media. When the capillary number is less than 3.5 × 10−5, the viscous fingering can be successfully suppressed and the transition from unstable to stable displacement can be achieved by the wetting gradient. Moreover, under the conditions of high viscosity ratio (M > 0.01) and large porosity (Φ > 0.58), wetting gradient improves the stability of the flow front more significantly.
Effect of Penetration Levels for Vehicle-to-Grid Integration on a Power Distribution Network
Authors: Simarro-García Ana , Villena-Ruiz Raquel , Honrubia-Escribano Andrés , Gómez-Lázaro Emilio
Published: March 2023

With the exponential growth of electric vehicle sales worldwide over the past years and progress in technology and actions to combat climate change by reducing greenhouse gas emissions, the trend is expected to continue with a significant increase in the deployment of electric vehicles and plug-in hybrids. Given these circumstances, it is essential to identify the constraints that this increase in the number of electric vehicle charging stations poses for the electricity system. Therefore, the analysis developed in this paper discusses the effect of integrating electric vehicle charging stations in a real distribution network with different penetration levels. For this purpose, a typical electric system in Greece, managed by the Greek distribution system operator (HEDNO), is modeled and simulated in DIgSILENT PowerFactory software, one of the most widely used simulation tools in the electricity sector. To study the feasibility of connecting electric vehicle charging stations to the network, different case studies are presented, showing changes in the quantity of electric vehicles feeding power into the network through vehicle-to-grid technology. Quasi-dynamic simulations are used to analyze and discuss the voltage profiles of the system nodes, active power flows with the external source and power losses of the distribution network to determine whether the system is capable of supporting the increase in load produced by the electric vehicle charging stations and to promote awareness of the benefits of implementing vehicle-to-grid connections.
Seismic Response and Damage Characteristics of RCC Gravity Dams Considering Weak Layers Based on the Cohesive Model
Authors: Wang Gaohui , Liu Aobo , Lu Wenbo , Chen Ming , Yan Peng
Published: March 2023

Due to the construction technology of roller compacted concrete (RCC) gravity dams, there are many weak layers that have the potential to affect the seismic performance of dams. However, research on the seismic response and failure characteristics of RCC dams considering their layered characteristic is still lacking. In this paper, the zero-thickness cohesive element is presented to model the mechanical behavior of the RCC layers. An impacted concrete beam is selected to verify its effects on simulating crack propagation. Subsequently, the concrete damaged plasticity model is utilized to model concrete under seismic loading. The dynamic interaction in the gravity dam-reservoir-foundation system is considered by coupled acoustic-structural method, whose rationality is validated by seismic failure mode analysis of the Koyna dam under the 1967 Koyna earthquake. The validated algorithms are applied to investigate the influence of the weak layer at different elevations on the seismic response and the failure process of the Guandi RCC gravity dam. On this basis, the effects of well-bonded RCC layers set at intervals along the dam on the nonlinear response and failure modes under strong earthquakes are further investigated. The results reveal that the weak layer will influence the anti-seismic capacity of RCC gravity dams, and the damage characteristics of the dam are significantly changed. In addition, well-bonded RCC layers still affect the seismic response of RCC gravity dams. Increasing displacement response and energy dissipation can be observed. Meanwhile, RCC layers lead to more severe damage to the dam under the same seismic input.
Finding the Best Dueler
Authors: Zhang Zhengu , Ross Sheldon M.
Published: March 2023

Consider a set of n players. We suppose that each game involves two players, that there is some unknown player who wins each game it plays with a probability greater than 1/2, and that our objective is to determine this best player. Under the requirement that the policy employed guarantees a correct choice with a probability of at least some specified value, we look for a policy that has a relatively small expected number of games played before decision. We consider this problem both under the assumption that the best player wins each game with a probability of at least some specified value p0>1/2, and under a Bayesian assumption that the probability that player i wins a game against player j is vivi+vj, where v1,…,vn are the unknown values of n independent and identically distributed exponential random variables. In the former case, we propose a policy where chosen pairs play a match that ends when one of them has had a specified number of wins more than the other; in the latter case, we propose a Thompson sampling type rule.
Reducing the Dimensionality of SPD Matrices with Neural Networks in BCI
Authors: Peng Zhen , Li Hongyi , Zhao Di , Pan Chengwei
Published: March 2023

In brain–computer interface (BCI)-based motor imagery, the symmetric positive definite (SPD) covariance matrices of electroencephalogram (EEG) signals with discriminative information features lie on a Riemannian manifold, which is currently attracting increasing attention. Under a Riemannian manifold perspective, we propose a non-linear dimensionality reduction algorithm based on neural networks to construct a more discriminative low-dimensional SPD manifold. To this end, we design a novel non-linear shrinkage layer to modify the extreme eigenvalues of the SPD matrix properly, then combine the traditional bilinear mapping to non-linearly reduce the dimensionality of SPD matrices from manifold to manifold. Further, we build the SPD manifold network on a Siamese architecture which can learn the similarity metric from the data. Subsequently, the effective signal classification method named minimum distance to Riemannian mean (MDRM) can be implemented directly on the low-dimensional manifold. Finally, a regularization layer is proposed to perform subject-to-subject transfer by exploiting the geometric relationships of multi-subject. Numerical experiments for synthetic data and EEG signal datasets indicate the effectiveness of the proposed manifold network.
Graphene Twistronics: Tuning the Absorption Spectrum and Achieving Metamaterial Properties
Authors: Armghan Ammar , Alsharari Meshari , Aliqab Khaled , Alsalman Osamah , Parmar Juveriya , Patel Shobhit K.
Published: March 2023

Graphene twistronics using multilayer graphene is presented in such a way that it provides a metamaterial effect. This manuscript also analyzes the prediction of behavior using machine learning. The metamaterial effect is achieved by twisting the graphene layers. Graphene twistronics is a new concept for changing the electrical and optical properties of bilayer graphene by applying a small angle twist between the layers. The angle twists of 5°, 10°, and 15° are analyzed for the proposed graphene twistronics design. Tuning in the absorption spectrum is achieved by applying small twists to the angles of the bilayer graphene. Results in the form of absorption, conductivity, permeability, permittivity, and impedance are presented for different twist angles. The twisted graphene layers also demonstrate negative permittivity and negative permeability, similar to metamaterials. These negative refraction properties of graphene twistronics provide flexibility and transparency, which can be applied in photovoltaic applications. Machine-learning-based regression models are used to reduce the simulation time and resources. The results show that a regression model can reliably estimate intermediate wavelength absorption values with an R2 of 0.9999.
Foley Catheter as a Tourniquet for Peripartum Hemorrhage Prevention in Patients with Placenta Accreta Spectrum—A Two Case Report and a Review of the Literature
Authors: Staniczek Jakub , Manasar-Dyrbuś Maisa , Skowronek Kaja , Winkowska Ewa , Stojko Rafał
Published: March 2023

One of the most perilous complications in obstetrics, often leading to severe bleeding and sometimes a need for urgent hysterectomy, is placenta accreta spectrum, which significantly increases the risk of peri-partum complications, even including the risk of death for the mother and the child. Dealing with excessive bleeding in this situation is paramount. We have found a Foley catheter tourniquet to be useful as a temporary tourniquet to control placental and uterine hemorrhage. We have used this method and find it very useful. In this publication, we describe the last two cases of the use of the Foley catheter as a tourniquet for peri-partum hemorrhage prevention, and we will present a review of the literature in this field.
A Systematic Review of Clinical Pharmacokinetics of Inhaled Antiviral
Authors: Alshammari Mohammed Kanan , Almutairi Mohammed Salem , Althobaiti Mohammed Dakhilallah , Alsawyan Watin Ahmed , Alomair Samar Abdulrahman , Alwattban Raghad Rsheed , Al Khozam Zahra Hassan , Alanazi Taif Jundi , Alhuqyal Abdullah S. , Darwish Hassan Saud Al , Alotaibi Abdulaziz Faisal , Almutairi Fahad Naif , Alanazi Abdullah Abdulrahman
Published: March 2023

Background and Objectives: The study of clinical pharmacokinetics of inhaled antivirals is particularly important as it helps one to understand the therapeutic efficacy of these drugs and how best to use them in the treatment of respiratory viral infections such as influenza and the current COVID-19 pandemic. The article presents a systematic review of the available pharmacokinetic data of inhaled antivirals in humans, which could be beneficial for clinicians in adjusting doses for diseased populations. Materials and Methods: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A comprehensive literature search was conducted using multiple databases, and studies were screened by two independent reviewers to assess their eligibility. Data were extracted from the eligible studies and assessed for quality using appropriate tools. Results: This systematic review evaluated the pharmacokinetic parameters of inhaled antiviral drugs. The review analyzed 17 studies, which included Zanamivir, Laninamivir, and Ribavirin with 901 participants, and found that the non-compartmental approach was used in most studies for the pharmacokinetic analysis. The outcomes of most studies were to assess clinical pharmacokinetic parameters such as the Cmax, AUC, and t1/2 of inhaled antivirals. Conclusions: Overall, the studies found that the inhaled antiviral drugs were well tolerated and exhibited favorable pharmacokinetic profiles. The review provides valuable information on the use of these drugs for the treatment of influenza and other viral respiratory infections.
Acquired Angioedema in Selected Neoplastic Diseases
Authors: Zając Magdalena , Bożek Andrzej , Kozłowska Renata , Grzanka Alicja
Published: March 2023

Background and Objectives. Acquired angioedema is a relatively common revelation accompanying some diseases such as autoimmune or cancer. The study aimed to assess the incidence of one subtype of angioedema—C1-INH-AAE (acquired angioedema with C1 inhibitor deficiency). Material and methods. The study was retrospective and based on 1 312 patients with a final diagnosis of breast cancer, colorectal cancer, or lung cancer: 723 women and 589 men with a mean age of 58.2 ± 13.5 years. The cancer diagnosis according to the ICD (International Classification of Diseases)-10 code, medical history including TNM (Tumour, Node, Metastasis) staging, histopathology, and assessment of the occurrence of C1-INH-AAE angioedema were analysed. Results. C1-INH-AAE occurred more often in patients with cancer than in the control group, as follows: 327 (29%) vs. 53 (6%) for p < 0.05. C1-INH-AAEs were observed most often in the group of patients diagnosed with breast cancer compared to colorectal and lung groups: 197 (37%) vs. 108 (26%) vs. 22 (16%) (p < 0.05). A higher incidence of C1-INH-AAE was observed in the early stages of breast cancer. However, there was no relationship between the occurrence of C1-INH-AAE and the BRCA1 (Breast Cancer gene 1)/BRCA2 (Breast Cancer gene 2) mutation or histopathological types of breast cancer. Conclusion. Angioedema type C1-INH-AAE occurs more often in patients with selected neoplastic diseases, especially in the early stages of breast cancer.
Antibiotic Usage in the COVID-19 Intensive Care Unit of an Infectious Diseases Hospital from Nord-Eastern Romania
Authors: Vâţă Andrei , Roşu Florin Manuel , Dorneanu Olivia Simona , Lehaci Alina Elisabeta , Luca Ştefana , Loghin Isabela Ioana , Miftode Ioana Diandra , Luca Cătălina Mihaela , Miftode Egidia Gabriela
Published: March 2023

Background and Objectives. The intensive care unit (ICU), especially in an infectious disease hospital, is both an area with a high consumption of antibiotics (atb) and a “reservoir” of multidrug-resistant bacteria. We proposed the analysis of antibiotic therapy practices in such a department that treated, in conditions of a pandemic wave, patients with COVID-19 and its complications. Materials and Methods. This was a retrospective transversal study of 184 COVID-19 patients treated in the ICU of a regional infectious disease hospital of Iaşi, Romania, in a 3-month interval of 2020 and 2021. Results. All the included patients (Caucasians, 53% males, with a median age of 68 years, and a Charlton comorbidity index of 3) received at least one antibiotic during their stay in the ICU (43% also had antibiotics prior to hospital admission and 68% in the Infectious Diseases ward). Only 22.3% of the ICU patients had only one antibiotic. A total of 77.7% of them started with an association of two antibiotics, and 19.6% of them received more than three antibiotics. The most-used ones were linezolid (77.2%), imipenem (75.5%), and ceftriaxone (33.7%). The median atb duration was 9 days. No change in the number or type of atb prescription was seen in 2021 (compared to 2020). Only 9.8% of the patients had a microbiological confirmation of bacterial infection. A total of 38.3% of the tested patients had elevated procalcitonin levels at ICU admission. The overall fatality rate was 68.5%, with no significant differences between the two analyzed periods or the number of administered antibiotics. More than half (51.1%) of the patients developed oral candidiasis during their stay in the ICU, but only 5.4% had C. difficile colitis. Conclusion. Antibiotics were widely used in our ICU patients in the presence of a reduced microbiological confirmation of a bacterial co-infection, and were justified by other clinical or biological criteria.
Retromode Imaging in Age-Related Macular Degeneration
Authors: Ranetti Antonia-Elena , Stanca Horia Tudor , Tăbăcaru Bogdana , Teodoru Adrian , Munteanu Mihnea , Stanca Simona
Published: March 2023

Background and Objectives: Retromode is a relatively new retinal-imaging technique that is based on the transillumination principle and is obtained with a scanning laser ophthalmoscope that uses light in the infrared spectrum. The laser light penetrates into the deep retinal layers and the choroid. Retromode images are captured with a laterally displaced aperture, and the detector captures only the scattered light. The result is a high-contrast pseudo-three-dimensional image. Age-related macular degeneration (AMD) is a disabling retinal disease. AMD is characterized in its early stage by small and intermediate drusen formation, while the signs of intermediate AMD are large drusen and/or pigmentary abnormalities. Late AMD has two forms, geographic atrophy, which is the advanced form of dry AMD, and wet AMD. Most of the lesions of AMD are located in the outer layers of the retina. This new imaging method can provide a glimpse of the deep retinal layers’ topographic changes in a non-invasive, fast, and effective way that can match the other imaging tools available. Materials and Methods: The literature review was performed by searching the PubMed database using the following combination of keywords: retromode imaging and age-related macular degeneration. Relevant images similar to the ones in the literature were identified and used as models. Results: The purpose of this article is to highlight the utility of incorporating retromode imaging into the multimodal evaluation of the retina in patients with AMD and to gather and integrate these findings into a brief but comprehensive paper. Conclusions: Retromode imaging is a good screening, diagnosis, and monitoring tool for patients with AMD.
Deformation and Fracture Characterization of an Mg-Sn-Ca Alloy Using 3D Processing Maps
Authors: Zhi Chenchen , Wu Zhenyu , Lei Junyi , Huang Zhiquan , Xv Haijie , Zhu Yanchun , Jia Weitao , Liu Pengtao , Ma Lifeng
Published: March 2023

The deformation and fracture characterization of an Mg−2Sn−1Ca alloy were studied through uniaxial isothermal compression tests. The flow stress curves, the efficiency of power dissipation, the instability parameter and the fracture behavior of an Mg−2Sn−1Ca alloy under the condition of various hot working parameters were investigated according to the experimental data. Processing maps were established by superimposing the instability map over the power dissipation map. It was found that flow stress reduces with increases in the deformation temperature and decreases in the strain rate. The processing of Mg−2Sn−1Ca alloys should avoid the instability region in which the conditions are high strain under high temperature and low strain under low temperature. At 473 K or a high strain rate, unidirectional cracks and fish scale cracks can be produced, and cracks can be avoided under the optimum processing area of 623–723 K/0.001–0.1 s−1.
Microstructural Evolution of Shear Localization in High-Speed Cutting of CoCrFeMnNi High-Entropy Alloy
Authors: Su Ming-Yao , Zhang Wei-Han , Tan Yuan-Yuan , Chen Yan , Wang Hai-Ying , Dai Lan-Hong
Published: March 2023

Shear localization is one of the most important failure mechanisms subjected to high-strain-rate deformation and has significant effects on the process, plastic deformation, and catastrophic failure of a material. Shear localization was observed in serrated chips produced during the high-speed cutting of the CoCrFeMnNi high-entropy alloy. Electron backscatter diffraction was performed to systematically investigate microstructural evolution during shear banding. The elongation and subdivision of the narrow grains were observed in the areas adjacent to the shear band. The microstructure inside the shear band was found to be composed of equiaxed ultrafine grains. The results reveal that grain subdivision and dynamic recrystallization might have significant roles in the microstructural evolution of shear bands. These results offer key insights into our understanding of shear localization and high-speed machining behavior for high entropy alloys.
Therapy-Resistant Acute Myeloid Leukemia Stem Cells Are Resensitized to Venetoclax + Azacitidine by Targeting Fatty Acid Desaturases 1 and 2
Authors: Culp-Hill Rachel , Stevens Brett M. , Jones Courtney L. , Pei Shanshan , Dzieciatkowska Monika , Minhajuddin Mohammad , Jordan Craig T. , D’Alessandro Angelo
Published: March 2023

Recent advances in targeting leukemic stem cells (LSCs) using venetoclax with azacitidine (ven + aza) has significantly improved outcomes for de novo acute myeloid leukemia (AML) patients. However, patients who relapse after traditional chemotherapy are often venetoclax-resistant and exhibit poor clinical outcomes. We previously described that fatty acid metabolism drives oxidative phosphorylation (OXPHOS) and acts as a mechanism of LSC survival in relapsed/refractory AML. Here, we report that chemotherapy-relapsed primary AML displays aberrant fatty acid and lipid metabolism, as well as increased fatty acid desaturation through the activity of fatty acid desaturases 1 and 2, and that fatty acid desaturases function as a mechanism of recycling NAD+ to drive relapsed LSC survival. When combined with ven + aza, the genetic and pharmacologic inhibition of fatty acid desaturation results in decreased primary AML viability in relapsed AML. This study includes the largest lipidomic profile of LSC-enriched primary AML patient cells to date and indicates that inhibition of fatty acid desaturation is a promising therapeutic target for relapsed AML.
Pressure Driven Rapid Reconfigurable Liquid Metal Patterning
Authors: Liu Bingxin , Qin Peng , Liu Mingyang , Liu Wei , Zhang Pan , Ye Zi , Deng Zhongshan , Li Zhenming , Gui Lin
Published: March 2023

This paper proposes a method for pressure driven rapid reconfigurable liquid metal patterning. A sandwich structure of “pattern—film—cavity” is designed to complete this function. Both sides of the highly elastic polymer film are bonded with two PDMS slabs. One PDMS slab has microchannels patterned on the surface. The other PDMS slab has a large cavity on its surface for liquid metal storage. These two PDMS slabs are bonded together, face to face, with the polymer film in the middle. In order to control the distribution of the liquid metal in the microfluidic chip, the elastic film will deform under the high pressure of the working medium in the microchannels and then extrude the liquid metal into different patterns in the cavity. This paper studies the factors of liquid metal patterning in detail, including external control conditions, such as the type and pressure of the working medium and the critical dimensions of the chip structure. Moreover, both a single-pattern and a double-pattern chip are fabricated in this paper, which can form or reconfigure the liquid metal pattern within 800 ms. Based on the above methods, reconfigurable antennas of two frequencies are designed and fabricated. Meanwhile, their performance is simulated and tested by simulation and vector network tests. The operating frequencies of the two antennas are respectively significantly switching between 4.66 GHz and 9.97 GHz.