bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the Use of Antibiotics for Dental Patients in a Middle-Income Country: Interviews with Clinicians in Two Ghanaian Hospitals
Authors: Sneddon Jacqueline , Thompson Wendy , Kpobi Lily N. A. , Ade Diana Abena , Sefah Israel Abebrese , Afriyie Daniel , Goldthorpe Joanna , Turner Rebecca , Nawaz Saher , Wilson Shona , Hart Jo , Byrne-Davis Lucie
Published: August 2022

Background: Antimicrobial resistance is a global problem driven by the overuse of antibiotics. Dentists are responsible for about 10% of antibiotics usage across healthcare worldwide. Factors influencing dental antibiotic prescribing are numerous, with some differences in low- and middle-income countries compared with high-income countries. This study aimed to explore the antibiotic prescribing behaviour and knowledge of teams treating dental patients in two Ghanaian hospitals. Methods: Qualitative interviews were undertaken with dentists, pharmacists, and other healthcare team members at two hospitals in urban and rural locations. Thematic and behaviour analyses using the Actor, Action, Context, Target, Time framework were undertaken. Results: Knowledge about ‘antimicrobial resistance and antibiotic stewardship’ and ‘people and places’ were identified themes. Influences on dental prescribing decisions related to the organisational context (such as the hierarchical influence of colleagues and availability of specific antibiotics in the hospital setting), clinical issues (such as therapeutic versus prophylactic indications and availability of sterile dental instruments), and patient issues such as hygiene in the home environment, delays in seeking professional help, ability to access antibiotics in the community without a prescription and patient’s ability to pay for the complete prescription. Conclusions: This work provides new evidence on behavioural factors influencing dental antibiotic prescribing, including resource constraints which affect the availability of certain antibiotics and diagnostic tests. Further research is required to fully understand their influence and inform the development of new approaches to optimising antibiotic use by dentists in Ghana and potentially other low- and middle-income countries.
Antimicrobial Resistance and Its Spread Is a Global Threat
Authors: Aljeldah Mohammed M.
Published: August 2022

Antimicrobial resistance (AMR) is a challenge to human wellbeing the world over and is one of the more serious public health concerns. AMR has the potential to emerge as a serious healthcare threat if left unchecked, and could put into motion another pandemic. This establishes the need for the establishment of global health solutions around AMR, taking into account microdata from different parts of the world. The positive influences in this regard could be establishing conducive social norms, charting individual and group behavior practices that favor global human health, and lastly, increasing collective awareness around the need for such action. Apart from being an emerging threat in the clinical space, AMR also increases treatment complexity, posing a real challenge to the existing guidelines around the management of antibiotic resistance. The attribute of resistance development has been linked to many genetic elements, some of which have complex transmission pathways between microbes. Beyond this, new mechanisms underlying the development of AMR are being discovered, making this field an important aspect of medical microbiology. Apart from the genetic aspects of AMR, other practices, including misdiagnosis, exposure to broad-spectrum antibiotics, and lack of rapid diagnosis, add to the creation of resistance. However, upgrades and innovations in DNA sequencing technologies with bioinformatics have revolutionized the diagnostic industry, aiding the real-time detection of causes of AMR and its elements, which are important to delineating control and prevention approaches to fight the threat.
Decreased Levels of GSH Are Associated with Platinum Resistance in High-Grade Serous Ovarian Cancer
Authors: Criscuolo Daniela , Avolio Rosario , Parri Matteo , Romano Simona , Chiarugi Paola , Matassa Danilo Swann , Esposito Franca
Published: August 2022

High-grade serous ovarian cancer (HGSOC) is the most common and aggressive OC histotype. Although initially sensitive to standard platinum-based chemotherapy, most HGSOC patients relapse and become chemoresistant. We have previously demonstrated that platinum resistance is driven by a metabolic shift toward oxidative phosphorylation via activation of an inflammatory response, accompanied by reduced cholesterol biosynthesis and increased uptake of exogenous cholesterol. To better understand metabolic remodeling in OC, herein we performed an untargeted metabolomic analysis, which surprisingly showed decreased reduced glutathione (GSH) levels in resistant cells. Accordingly, we found reduced levels of enzymes involved in GSH synthesis and recycling, and compensatory increased expression of thioredoxin reductase. Cisplatin treatment caused an increase of reduced GSH, possibly due to direct binding hindering its oxidation, and consequent accumulation of reactive oxygen species. Notably, expression of the cysteine-glutamate antiporter xCT, which is crucial for GSH synthesis, directly correlates with post-progression survival of HGSOC patients, and is significantly reduced in patients not responding to platinum-based therapy. Overall, our data suggest that cisplatin treatment could positively select cancer cells which are independent from GSH for the maintenance of redox balance, and thus less sensitive to cisplatin-induced oxidative stress, opening new scenarios for the GSH pathway as a therapeutic target in HGSOC.
Stress Hormones Cortisol and Aldosterone, and Selected Markers of Oxidative Stress in Response to Long-Term Supplementation with Omega-3 Fatty Acids in Adolescent Children with Depression
Authors: Oravcova Henrieta , Katrencikova Barbora , Garaiova Iveta , Durackova Zdenka , Trebaticka Jana , Jezova Daniela
Published: August 2022

Late childhood and adolescence are crucial periods of brain development with high vulnerability to environmental insults. The aim of this study was to test the hypotheses that in adolescents with depression (a) 12 weeks-supplementation with omega-3 fatty acids results in the attenuation of salivary stress hormone concentrations; (b) the mentioned supplementation improves potentially disrupted daily rhythm of stress hormones; (c) stress hormone concentrations correlate with values of selected markers of oxidative stress. The sample consisted of 60 patients suffering from depression aged 11–18 years. Hormone concentrations in saliva were measured in the morning and midday before (baseline) and after (6, 12 weeks) food supplementation with omega-3 or omega-6 (as comparator) fatty acids. Morning cortisol decreased in response to omega-3 but not omega-6 fatty acids at 12 weeks compared to baseline. No changes were observed in aldosterone concentrations. The obtained results show that adolescent children with depression preserved the daily rhythm of both stress hormones. Baseline morning cortisol concentrations correlated positively with depression severity and lipoperoxides, and negatively with docosahexaenoic acid. Aldosterone concentrations correlated positively with 8-isoprostane. Thus, both hormones showed positive correlation with the selected markers of oxidative stress suggesting that enhanced stress hormone secretion may be associated with increased oxidative tissue damage in adolescent children with depression. This study was registered with the ISRCTN registry (DEPOXIN study, ISRCTN81655012).
Role of Nuclear Factor Erythroid 2 (Nrf2) in the Recovery of Long COVID-19 Using Natural Antioxidants: A Systematic Review
Authors: Muchtaridi Muchtaridi , Amirah Siti Rafa , Harmonis Jacko Abiwaqash , Ikram Emmy Hainida Khairul
Published: August 2022

Coronavirus disease 2019 (COVID-19) is an infectious disease with approximately 517 million confirmed cases, with the average number of cases revealing that patients recover immediately without hospitalization. However, several other cases found that patients still experience various symptoms after 3–12 weeks, which is known as a long COVID syndrome. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can activate nuclear factor kappa beta (NF-κβ) and unbind the nuclear factor erythroid 2-related factor 2 (Nrf2) with Kelch-like ECH-associated protein 1 (Keap1), causing inhibition of Nrf2, which has an important role in antioxidant response and redox homeostasis. Disrupting the Keap1–Nrf2 pathway enhances Nrf2 activity, and has been identified as a vital approach for the prevention of oxidative stress and inflammation. Hence, natural antioxidants from various sources have been identified as a promising strategy to prevent oxidative stress, which plays a role in reducing the long COVID-19 symptoms. Oxygen-rich natural antioxidant compounds provide an effective Nrf2 activation effect that interact with the conserved amino acid residues in the Keap1-binding pocket, such as Ser602, Ser363, Ser508, and Ser555. In this review, the benefits of various natural antioxidant compounds that can modulate the Nrf2 signaling pathway, which is critical in reducing and curing long COVID-19, are highlighted and discussed.
Application of Response Surface Methodologies to Optimize High-Added Value Products Developments: Cosmetic Formulations as an Example
Authors: Leyva-Jiménez Francisco-Javier , Fernández-Ochoa Álvaro , Cádiz-Gurrea María de la Luz , Lozano-Sánchez Jesús , Oliver-Simancas Rodrigo , Alañón M. Elena , Castangia Ines , Segura-Carretero Antonio , Arráez-Román David
Published: August 2022

In recent years, green and advanced extraction technologies have gained great interest to revalue several food by-products. This by-product revaluation is currently allowing the development of high value-added products, such as functional foods, nutraceuticals, or cosmeceuticals. Among the high valued-added products, cosmeceuticals are innovative cosmetic formulations which have incorporated bioactive natural ingredients providing multiple benefits on skin health. In this context, the extraction techniques are an important step during the elaboration of cosmetic ingredients since they represent the beginning of the formulation process and have a great influence on the quality of the final product. Indeed, these technologies are claimed as efficient methods to retrieve bioactive compounds from natural sources in terms of resource utilization, environmental impact, and costs. This review offers a summary of the most-used green and advanced methodologies to obtain cosmetic ingredients with the maximum performance of these extraction techniques. Response surface methodologies may be applied to enhance the optimization processes, providing a simple way to understand the extraction process as well as to reach the optimum conditions to increase the extraction efficiency. The combination of both assumes an economic improvement to attain high value products that may be applied to develop functional ingredients for cosmetics purposes.
Determining Optimal Power Flow Solutions Using New Adaptive Gaussian TLBO Method
Authors: Alanazi Abdulaziz , Alanazi Mohana , Memon Zulfiqar Ali , Mosavi Amir
Published: August 2022

A key component of the design and operation of power transmission systems is the optimal power flow (OPF) problem. To solve this problem, several optimization algorithms have been developed. The primary objectives of the program are to minimize fuel costs, reduce emissions, improve voltage profiles, and reduce power losses. OPF is considered one of the most challenging optimization problems due to its nonconvexity and significant computational difficulty. Teaching–learning-based optimization (TLBO) is an optimization algorithm that can be used to solve engineering problems. Although the method has certain advantages, it does have one significant disadvantage: after several iterations, it becomes stuck in the local optimum. The purpose of this paper is to present a novel adaptive Gaussian TLBO (AGTLBO) that solves the problem and improves the performance of conventional TLBO. Validating the performance of the proposed algorithm is undertaken using test systems for IEEE standards 30-bus, 57-bus, and 118-bus. Twelve different scenarios have been tested to evaluate the algorithm. The results show that the proposed AGTLBO is evidently more efficient and effective when compared to other optimization algorithms published in the literature.
Finite Element Assessment of a Hybrid Proposal for Hip Stem, from a Standardized Base and Different Activities
Authors: Guzmán Manuel , Durazo Emmanuel , Ortiz Alejandro , Sauceda Israel , Siqueiros Miriam , González Luis , Jiménez David
Published: August 2022

Choosing a suitable prosthesis to restore the functionality of the hip joint is a complex problem. The stem geometries, materials, and type of hip damage are critical factors for avoiding potential issues (aseptic loosening, fracture, and natural wear and tear). Comparing the available stems to select the best option is not straightforward because of the various loads and boundary conditions used in the tests, making the process difficult to compare the advantages and disadvantages among them. This work proposes stem assessment using a standardized base (generated from a literature review and ISO standards) to compare the stem geometries and present a new hybrid design to improve performance using the best qualities of the implants reported in the literature review. Sixteen hip prostheses were evaluated with the finite element method (FEM) using the same boundary and loading conditions through multi-objective analysis (von Mises stress and strain). Consequently, a hybrid geometry proposal was obtained by assessing specific points through the stem length (medial and lateral region) to define the cross-section (trapezoidal) and the new profile. The new hybrid implant proposal presented a stress reduction of 9.6% when compared to the reference implant P2-T (the implant with the best behavior) in the most critical activity (activity 4) using a titanium alloy. A similar stress reduction of 9.98% was obtained using ASTM F2996-13 and ISO 7206–4:2010(E) standards.
Traffic Monitoring from the Perspective of an Unmanned Aerial Vehicle
Authors: Kainz Ondrej , Dopiriak Matúš , Michalko Miroslav , Jakab František , Nováková Ivana
Published: August 2022

The paper is focused on the development of the experimental web-based solution for image processing from the perspective of an Unmanned Aerial Vehicle (UAV). Specifically, the research is carried out as part of the broader study on drone utilization in traffic at the Technical University of Kosice. This contribution explores the possibility of using the UAV as a tool to detect the temporal state of the traffic in multiple locations. Road traffic analysis is enabled through the detection of vehicles from the user-defined region of interest (ROI). Its content then serves as the input for motion detection, followed by the detection of vehicles using the YOLOv4 model. Detection of other types of objects is possible, thus making the system more universal. The vehicle is tracked after recognition in two consecutive frames. The tracking algorithm is based on the calculation of the Euclidean distance and the intersection of the rectangles. The experimental verification yields lower hardware requirements for CPU and GPU by about two FPS when using optimization techniques, such as ROI or reference dimensions of objects. The accuracy of detection and the subsequent tracking of cars reaches almost 100% while providing accurate trajectory determination.
Numerical Study on the Pressure Relief Characteristics of a Large-Diameter Borehole
Authors: Cui Feng , Zhang Suilin , Chen Jianqiang , Jia Chong
Published: August 2022

Large-diameter drilling is an effective method for preventing rock burst disasters in coal mines. In this paper, the roadway stability of the W1123 fully mechanized caving work face of the Kuangou coal mine, located in northwest China, is investigated. A set of numerical modelling techniques were carried out to study the characteristics of stress, displacement, strain energy and the plastic zone of the roadway side rock with different parameters, including the large-diameter drilling hole diameter, depth and spacing. The results showed that: (1) after drilling, the peak values of the stress and strain energy are reduced and transferred to a deeper location, and the control effect presents a positive correlation with the diameter of the drilling hole; (2) when Lh < LP, there are no pressure relief and energy release effects, which may induce impact, whereas when LP < Lh ≤ 2.5LP, with the increase of the hole depth, the effects of pressure relief and energy release are enhanced, and further extension is not conducive to the long-term stability of the roadway; and (3) when the hole spacing decreases, the plastic zone and the broken zone between the holes are gradually penetrated, and the stress pattern transforms from a double peak to a saddle shape and then to single peak. Reducing the hole diameter reduces the efficiency of the plastic zone, failure zone and the stress form transformation between the boreholes, and weakens the pressure relief effect. Therefore, the main factor affecting the pressure relief effect is the hole diameter, and the secondary factor is the hole spacing. The engineering practice employed here showcases how a larger-diameter hole is an effective way of enhancing the effect of pressure relief and controlling the occurrence of rock burst. These research results are of great significance for guiding engineering practice.
A Novel Natural Active Coagulant Agent Extracted from the Sugarcane Bagasse for Wastewater Treatment
Authors: Bahrodin Muhammad Burhanuddin , Zaidi Nur Syamimi , Kadier Abudukeremu , Hussein Norelyza , Syafiuddin Achmad , Boopathy Raj
Published: August 2022

The performance of extracted coagulant from the sugarcane bagasse was tested using synthetic wastewater for turbidity removal. Sugarcane bagasse was selected because it is available in abundance as a waste. This study was carried out to analyze the effect of the extraction process in optimizing the active coagulant agent of bagasse as a natural coagulant for optimum turbidity removal. Bagasse was characterized in terms of physical, chemical and morphological properties. The results showed bagasse has very high polysaccharide content which can act as an active coagulant agent together with hemicellulose and lignin. The extraction process for degradation of lignin and hemicellulose was run based on two different solvents (NaOH and H2SO4) with varying concentrations from 2% to 10% at different extraction temperatures varied from 60 °C to 180 °C for various extraction times (0.5 h to 3 h). The optimum polysaccharide content extracted from bagasse was 697.5 mg/mL by using 2% NaOH at 120 °C for 2 h extraction. The coagulation process using extracted bagasse showed the removal of suspended solids up to 95.9% under optimum conditions. The concentration of polysaccharides as the active coagulant agent plays a vital role where high polysaccharides content removes most turbidity at a lower dosage. Bagasse has the potential to be an alternative coagulating agent due to its efficiency, and eco-friendly properties for the treatment of wastewater.
Centrifuge Model Investigation of Interaction between Successively Constructed Foundation Pits
Authors: Chen Shangrong , Cui Jifei , Liang Fayun
Published: August 2022

A series of centrifuge model tests were conducted to study the interaction between successively constructed adjacent foundation pits. The stress, deformation, and earth pressure on retaining structures and the settlement of the soil between the two adjacent foundation pits during successive construction were investigated by a comprehensive instrumentation program. To reveal the effect of the construction sequence, both the stress and deformation of successively constructed foundation pits were compared. The results showed that the stress and deformation of the retaining structure in the foundation pit constructed first were larger than those in the foundation pit constructed later. Due to the inward displacement of the soil around the foundation pits excavated first, the first strut of the foundation pit constructed later underwent high tension during the construction of the first foundation pit. The lateral deformation of the retaining structure of the foundation pit excavated first increased with the increase of the excavation depth. However, the excavation of the second foundation pit reduced the earth pressure on the retaining wall between the two excavations, thus leading to the recovery of the inward deformation in the first excavation. However, the top of the retaining wall deformed into the first foundation pit during the whole construction. The settlement of the soil between the two foundation pits showed a superposition effect. During the construction of the two foundation pits, the settlement of the soil between them kept increasing. The active earth pressure on the middle wall of the foundation pit constructed later was lower than that on the middle wall of the first foundation pit. The excavation of the foundation pit constructed later had no significant effect on the passive earth pressure of the first foundation pit.
Corrosion Assessment of Zr2.5Nb Alloy in Ringer’s Solution by Electrochemical Methods
Authors: Neaga Veaceslav , Benea Lidia , Axente Elena Roxana
Published: August 2022

This study aims to investigate the anticorrosive properties of Zr2.5Nb alloy intended for possible applications in the human body; it was tested for 2 days in Ringer solution (an artificial analogue for human blood, considered the most corrosive body fluid). For Zr2.5Nb samples, in situ electrochemical measurements to assess the anticorrosive properties were applied, such as open circuit potential (OCP), polarization resistance (Rp), potentiodynamic polarization (PD) and cyclic voltammetry (CV). The electrochemical results show that the Zr2.5Nb alloy shows a positive and stable trend according to the open circuit potential, but with a modest corrosion rate in the form of pitting, deduced from the analysis of the polarization resistance and cyclic voltammetry data.
A Model-Driven Approach for Conducting Simulation Experiments
Authors: Wilsdorf Pia , Heller Jakob , Budde Kai , Zimmermann Julius , Warnke Tom , Haubelt Christian , Timmermann Dirk , van Rienen Ursula , Uhrmacher Adelinde M.
Published: August 2022

With the increasing complexity of simulation studies, and thus increasing complexity of simulation experiments, there is a high demand for better support for them to be conducted. Recently, model-driven approaches have been explored for facilitating the specification, execution, and reproducibility of simulation experiments. However, a more general approach that is suited for a variety of modeling and simulation areas, experiment types, and tools, which also allows for further automation, is still missing. Therefore, we present a novel model-driven engineering (MDE) framework for simulation studies that extends the state-of-the-art of conducting simulation experiments in the following ways: (a) Providing a structured representation of the various ingredients of simulation experiments in the form of meta models and collecting them in a repository improves knowledge sharing across application domains and simulation approaches. (b) Specifying simulation experiments in the quasi-standardized form of the meta models (e.g., via a GUI) and, subsequently, performing the automatic generation of experiment specifications in a language of choice increases both the productivity and quality of complex simulation experiments. (c) Automatic code transformation between specification languages via the meta models enables the reusability of simulation experiments. (d) Integrating the framework using a command-line interface allows for further automation of subprocesses within a simulation study. We demonstrate the advantages and practicality of our approach using real simulation studies from three different fields of simulation (stochastic discrete-event simulation of a cell signaling pathway, virtual prototyping of a neurostimulator, and finite element analysis of electric fields) and various experiment types (global sensitivity analysis, time course analysis, and convergence testing). The proposed framework can be the starting point for further automation of simulation experiments and, therefore, can assist in conducting simulation studies in a more systematic and effective manner. For example, based on this MDE framework, approaches for automatically selecting and parametrizing experimentation methods, or for planning follow-up activities depending on the context of the simulation study, could be developed.
A Two-Stage Decomposition-Reinforcement Learning Optimal Combined Short-Time Traffic Flow Prediction Model Considering Multiple Factors
Authors: Qu Dayi , Chen Kun , Wang Shaojie , Wang Qikun
Published: August 2022

Accurate short-term traffic flow prediction is a prerequisite for achieving an intelligent transportation system to proactively alleviate traffic congestion. Considering the complex and variable traffic environment, so that the traffic flow contains a large number of non-linear characteristics, which makes it difficult to improve the prediction accuracy, a combined prediction model that reduces the unsteadiness of traffic flow and fully extracts the traffic flow features is proposed. Firstly, decompose the traffic flow data into multiple components by the seasonal and trend decomposition using loess (STL); these components contain different features, and the optimized variational modal decomposition (VMD) is used for the second decomposition of the component with large fluctuation frequencies, and then the components are reconstructed according to the fuzzy entropy and Lempel-Ziv complexity index and the Pearson correlation coefficient is used to filter the traffic flow features. Then light gradient boosting machine (LightGBM), long short-term memory with attention mechanism (LA), and kernel extreme learning machine with genetic algorithm optimization (GA-KELM) are built for prediction. Finally, we use reinforcement learning to integrate the advantages of each model, and the weights of each model are determined to obtain the best prediction results. The case study shows that the model established in this paper is better than other models in predicting urban road traffic flow, with an average absolute error of 2.622 and a root mean square error of 3.479, both of which are lower than the prediction errors of other models, indicating that the model can fully extract the features in complex traffic flow.
Seven-Phase PMSM Drives Operation Post Two Types of Faults
Authors: Saleh Kamel
Published: August 2022

This research presents a seven-phase PMSM drive with a high degree of reliability. This enhancement in reliability is achieved by applying two new Fault Tolerant Control techniques (FTC) at the same time. The first FTC will maintain the operation of the seven-phase PMSM drive after the failure in one based on the minimum inverter current optimization technique. The implementation of this FTC technique is achieved through developing a novel Space Vector Pulse Width Modulation (SVPWM) to assure proper distribution of the currents in the remaining phases post failure. The second FTC technique keeps the operation of the faulty seven-phase PMSM drive post the failure in the speed sensor. This is created by developing a new algorithm to obtain the rotor position and speed of the faulty seven-phase PMSM drive based on the voltage excitation method. Simulation results are presented to demonstrate the enhancement in the reliability achieved by the FTCs developed in this paper for the seven-phase motor drive running post the failures in phase ‘A’ and the speed sensor at the same time.
Carrot Pomace Characterization for Application in Cereal-Based Products
Authors: Luca Marian Ilie , Ungureanu-Iuga Mădălina , Mironeasa Silvia
Published: August 2022

Carrot is one of the most consumed vegetables worldwide and the production of juices generates high amounts of valuable by-products such as pomace. In order to minimize the environmental effects and to optimize the production costs, carrot pomace can be considered as an ingredient in various food products. The aim of this study was to characterize carrot pomace powders from four varieties (Baltimore, Niagara, Belgrado, and Sirkana) and, from a chemical, functional, chromatic, microstructural, and molecular point of view, highlight the possibility of using them as food ingredients. The results obtained showed that the chemical composition, functional properties, color, and molecular structures of carrot pomace powders depend on the variety. Carrot pomace powders had high contents of fibers (20.09–33.34%), carbohydrates (46.55–58.95%), ash (5.29–5.89%), and proteins (6.87–9.14%), with the Belgrado variety being the richest in fibers and ash, while the Sirkana variety had the greatest protein and the smallest carbohydrate content. With respect to the functional properties, significant differences among the samples were recorded for water absorption and retention capacities, with the Baltimore carrot pomace presenting the highest values (16.99% and 7.64 g/g, respectively). All of the samples exhibited high foaming stability (FS > 94%), with the hydration capacity being higher than 57.96%, the oil absorption capacity being greater than 34.33%, and the bulk density comprised between 0.45 and 0.56 g/cm3. The highest luminosity was obtained for the Baltimore sample (73.30), while the Niagara variety exhibited the most yellowish (19.61), reddish (13.05), and intense (23.55) color. The microstructure of all the samples were compact, while the FT-IR spectra depicted the presence of beta carotene, fibers, carbohydrates, lipids, and proteins. These results could be helpful for processors and researchers interested in reducing their carbon foot print in the fruit processing industry and/or in creating food products with enriched nutritional and functional values.
Numerical Analysis of Instability Mechanism of a High Slope under Excavation Unloading and Rainfall
Authors: Qu Manli , Dang Faning
Published: August 2022

High slope simulation analysis is an essential means of slope engineering design, construction, and operation management. It is necessary to master slope dynamics, ensure slope safety, analyze slope instability mechanisms, and carry out slope stability early warning and prediction. This paper, aiming at the landslide phenomenon of the high slope on the left bank of a reservoir project, considering the influence of stratum lithology, fault, excavation unloading, rainfall, and water storage, establishes a refined finite element model that reflects the internal structure of the slope. The fluid-solid coupling numerical simulation analysis of the high slope is carried out. Based on this, the failure mechanism of the slope under excavation unloading and heavy rainfall is explained. The application of an engineering example shows that under the combined action of excavation unloading and rainfall infiltration, the in-plane saturation of the structure formed at fault at the trailing edge of the excavation slope surface increases, the pore water pressure increases, and the shear strain concentration area appears at the internal structural surface of the slope. The shear strain concentration area extends along the structural surface to the front and rear edges of the slope, resulting in landslide damage.
Spin Probes as Scavengers of Free Radicals in Cells
Authors: Dobosz Bernadeta , Krzyminiewski Ryszard , Kucińska Małgorzata , Murias Marek , Schroeder Grzegorz , Kurczewska Joanna
Published: August 2022

Spin probes can be used to monitor biological membranes, including the penetration of different molecules into cells. The aim of the present studies was an investigation of the endocytosis process of two spin labels—2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO) and 4-hydroxy-TEMPO (TEMPOL)—into yeast cells and a leukemia cell line (HL-60, ATCC CCL-240) by Electron Spin Resonance (ESR). The ESR method is helpful for the direct detection of free radicals. The cell incubation and endocytosis of spin probes were carried out at 310 K. In contrast, the ESR measurements of yeast cells and a leukemia cell line with spin probes were at 240 K. Spectral differentiation was observed; hence, the spin probes present in suspension and attached to the cell membrane could be distinguished. The ESR signal changes of spin probes depended on spin probe concentration, cell number, and type of cell (healthy/cancerous). Additionally, the effect of external factors (oxygen and vitamin C) on the ESR signal decay of spin markers in the cell solution was established. The experimental results prove that the spin probes (TEMPO and TEMPOL) could scavenge free radicals inside the cell. At the same time, the mechanism of spin probe interaction in suspension was determined based on the measurements at low temperatures.
Preservation of Cultural Heritage Using Virtual Reality Technologies and Haptic Feedback: A Prototype and Case Study on Antique Carpentry Tools
Authors: Antonya Csaba , Butnariu Silviu
Published: August 2022

Over the last decade, there have been intense concerns at the European and global level regarding the recovery, protection, and promotion of cultural heritage in various forms: monuments, historical sites, artifacts, cultural expressions. The world is becoming more and more aware of the loss of honor elements of cultural heritage due to the passage of time, natural or man-made disasters, negligence, and improper conservation. This paper aims to develop a tool to improve the visibility of elements that may become rare in everyday life over the coming years, becoming elements of cultural heritage. The paper refers to a haptic system for simulating kinematic and dynamic operating conditions based on an articulated mechanism, more precisely, the simulation of the operation of a manual saw as a carpentry tool, visualizing the sawing maneuver and increasing the level of understanding of the operation by the possibility of modifying the working parameters. In the developed virtual reality environment, the user’s perception can benefit by evoking two of their senses—the user can see the operation of the hand saw and can feel the manual process of cutting wood. User studies were carried out to evaluate the usability and performance of the virtual reality application. In two test scenarios, 20 people gave positive feedback in using custom-made haptic devices for various categories (engagement, manipulability, enjoyment, realism, usability, overall experience).
Optimal Design and Experiment of Manipulator for Camellia Pollen Picking
Authors: Zhao Qing , Li Lijun , Wu Zechao , Guo Xin , Li Jun
Published: August 2022

In this paper, a four-degree-of-freedom camellia-pollen-picking manipulator is proposed and designed. It can solve the problem of having no mechanized equipment for picking camellia pollen in agricultural machinery as the labor intensity of manual pollen extraction is high. To make the manipulator reach the target space quickly and efficiently, a structural-parameter-optimization method that reduces the working space to a more versatile cube is proposed. The numerical optimization algorithm is used to calculate the optimization result. Through the static analysis of the manipulator, the stability of the manipulator structure is verified. The working space of the manipulator is simulated and analyzed, and the simulation results are further verified by experiments. This research provides reliable technical support for the structural optimization, manufacturing, and intelligent upgrading of the camellia-pollen-picking robot.
Emotions in the Psychology of Aesthetics
Authors: Funch Bjarne Sode
Published: August 2022

Ever since Alexander Gottlieb Baumgarten (1714–1762) introduced the concept of aesthetics, the prevailing idea has been that the fine arts provide an alternative source of knowledge to the traditional sciences. Art, however, has always been closely associated with emotions. Taking Baumgarten’s treatise on poetry as a point of departure, I argue that Baumgarten laid the ground for a conception of art that emphasizes emotion rather than cognition with a particular appeal to psychology to provide principles of aesthetic appreciation of art. This appeal is met here with a phenomenological discussion of a series of precepts within contemporary emotion theories, which provides the necessary and sufficient conditions for a psychological theory of aesthetic appreciation of art.
Health Exposure Assessment of Firefighters Caused by PAHs in PM4 and TSP after Firefighting Operations
Authors: Rakowska Joanna , Rachwał Marzena , Walczak Agata
Published: August 2022

Among the many different chemicals in the air, polycyclic aromatic hydrocarbons (PAHs) pose a serious threat to human health. Firefighters are exposed to them both during fire suppression and in fire vehicles and fire stations due to inhalation of the fumes from contaminated clothing and personal protective equipment. This study aimed to estimate the exposure and cancer risk caused by suspended particulate matter and PAHs present in these particles. Air samples were collected for 4 months in a garage of the fire station in a small town, located in an urban–rural area. PAH concentrations were measured using the gas chromatography method with mass spectrometry (GC/MS). The concentration of PM4 (particulate matter with a diameter below 4µm) and TSP (total suspended particulate) in the fire station garage was 7 and 9 times higher than outside, respectively. The calculated values of health hazard risks associated with the exposure to PAHs in PM4 and TSP are: a toxic equivalent (TEQ) up to 10.36 and 23.3, incremental lifetime cancer risk (ILCR) up to 3.45 and 4.65 and hazard quotient (HQ) up to 0.42 and 0.57, respectively. A significantly increased risk of cancers in the professional group of firefighters was found.
Assessment of Drought Severity and Their Spatio-Temporal Variations in the Hyper Arid Regions of Kingdom of Saudi Arabia: A Case Study from Al-Lith and Khafji Watersheds
Authors: Ejaz Nuaman , Bahrawi Jarbou
Published: August 2022

The goal of this study is to calculate meteorological drought using the Standard Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index (SPEI) for the Al-Lith and Khafji basins of the Kingdom of Saudi Arabia (KSA) from 2001 to 2020. The in situ (rain gauges, RGs) and Integrated Multi-satellite Retrievals for GPM (IMERG) data are used in the current study. The meteorological drought is monitored across the AL-Lith and Khafji watersheds. The climate of the Khafji watershed is like the climate of Al-Lith to some extent. Still, due to complex terrain, Al-Lith receives relatively high precipitation and has a higher average temperature than the Khafji watershed. Results show that the total drought periods observed are 166 and 139 months based on SPEI and SPI on a multiple time scale (1, 3, 6, and 12 months) in the Al-Lith watershed, respectively. While, based on SPEI and SPI, the Khafji watershed experienced a drought of 129 and 72 months, respectively. This finding indicates that the SPEI-calculated drought is more severe and persistent in both watersheds than the SPI-calculated drought. Additionally, the correlation coefficient (CC) between SPI and SPEI is investigated; a very low correlation is observed at a smaller scale. CC values of 0.86 and 0.93 for Al-Lith and 0.61 and 0.79 for the Khafji watershed are observed between SPEI-1/SPI-1 and SPEI-3/SPI-3. However, the correlation is significant at high temporal scales, i.e., 6 and 12 months, with CC values of 0.95 and 0.98 for Al-Lith and 0.86 to 0.94 for the Khafji watershed. Overall, the study compared the performance of IMERG with RGs to monitor meteorological drought, and IMERG performed well across both watersheds during the study period. Therefore, the current study recommends the application of IMERG for drought monitoring across data-scarce regions of KSA. Furthermore, SPEI estimates a more severe and long-lasting drought than SPI because of the temperature factor it considers.
Modelling Cloud Cover Climatology over Tropical Climates in Ghana
Authors: Dogbey Felicia , Asilevi Prince Junior , Dzrobi Joshua Fafanyo , Koffi Hubert Azoda , Klutse Nana Ama Browne
Published: August 2022

Clouds play a crucial role in Earth’s climate system by modulating radiation fluxes via reflection and scattering, and thus the slightest variation in their spatial coverage significantly alters the climate response. Until now, due to the sparse distribution of advanced observation stations, large uncertainties in cloud climatology remain for many regions. Therefore, this paper estimates total cloud cover (TCC) by using sunshine duration measured in different tropical climates in Ghana. We used regression tests for each climate zone, coupled with bias correction by cumulative distribution function (CDF) matching, to develop the estimated TCC dataset from nonlinear empirical equations. It was found that the estimated percentage TCC, 20.8–84.7 ± 3.5%, compared well with station-observed TCC, 21.9–84.4 ± 3.5%, with root mean square errors of 1.08–9.13 ± 1.8% and correlation coefficients of 0.87–0.99 ± 0.03. Overall, spatiotemporal characteristics were preserved, establishing that denser clouds tended to prevail mostly over the southern half of the forest-type climate during the June–September period. Moreover, the model and the observations show a non-normality, indicating a prevalence of above-average TCC over the study area. The results are useful for weather prediction and application in meteorology.
Differential Radiosensitizing Effect of 50 nm Gold Nanoparticles in Two Cancer Cell Lines
Authors: Pérez-Amor Miguel Ángel , Barrios Leonardo , Armengol Gemma , Barquinero Joan Francesc
Published: August 2022

Radiation therapy is widely used as an anti-neoplastic treatment despite the adverse effects it can cause in non-tumoral tissues. Radiosensitizing agents, which can increase the effect of radiation in tumor cells, such as gold nanoparticles (GNPs), have been described. To evaluate the radiosensitizing effect of 50 nm GNPs, we carried out a series of studies in two neoplastic cell lines, Caco2 (colon adenocarcinoma) and SKBR3 (breast adenocarcinoma), qualitatively evaluating the internalization of the particles, determining with immunofluorescence the number of γ-H2AX foci after irradiation with ionizing radiation (3 Gy) and evaluating the viability rate of both cell lines after treatment by means of an MTT assay. Nanoparticle internalization varied between cell lines, though they both showed higher internalization degrees for functionalized GNPs. The γ-H2AX foci counts for the different times analyzed showed remarkable differences between cell lines, although they were always significantly higher for functionalized GNPs in both lines. Regarding cell viability, in most cases a statistically significant decreasing tendency was observed when treated with GNPs, especially those that were functionalized. Our results led us to conclude that, while 50 nm GNPs induce a clear radiosensitizing effect, it is highly difficult to describe the magnitude of this effect as universal because of the heterogeneity found between cell lines.
Soluble Flt-1 in AMI Patients Serum Inhibits Angiogenesis of Endothelial Progenitor Cells by Suppressing Akt and Erk’s Activity
Authors: Zhang Lijie , Zhang Xingkun , Zhong Xiaoming , Fan Mengya , Wang Guoliang , Shi Wei , Xie Ran , Wei Yinxiang , Zhang Hailong , Meng Xiangxu , Wang Yaohui , Ma Yuanfang
Published: August 2022

In acute myocardial infarction (AMI), endothelial progenitor cells (EPCs) are essential for the recovery of collateral circulation via angiogenesis. Clinical research has shown that the poor prognosis of the patients with AMI is closely associated with the cell quantity and function of EPCs. Whether there are differences in the biological features of EPCs from AMI patients and healthy subjects is worth exploring. In this study, EPCs were isolated from human peripheral blood and identified as late-stage EPCs by flow cytometry, immunofluorescence, and blood vessel formation assay. Compared to healthy subjects, AMI patients had more EPCs in the peripheral blood compared to healthy subjects. In addition, EPCs from AMI patients exhibited higher migration ability in the transwell assay compared to EPCs from healthy subjects. However, no difference in the angiogenesis of EPCs was observed between AMI patients and healthy subjects. Further studies revealed that soluble vascular endothelial growth factor receptor 1 (sFlt-1) in the serum of AMI patients was involved in the inhibition of EPCs angiogenesis by suppressing the Akt and Erk pathways. In conclusion, this study demonstrated that elevated serum sFlt-1 inhibits angiogenesis of EPC in AMI patients. Our findings uncover a pathogenic role of sFlt-1 in AMI.
Trebouxia lynnae sp. nov. (Former Trebouxia sp. TR9): Biology and Biogeography of an Epitome Lichen Symbiotic Microalga
Authors: Barreno Eva , Muggia Lucia , Chiva Salvador , Molins Arantzazu , Bordenave César , García-Breijo Francisco , Moya Patricia
Published: August 2022

Two microalgal species, Trebouxia jamesii and Trebouxia sp. TR9, were detected as the main photobionts coexisting in the thalli of the lichen Ramalina farinacea. Trebouxia sp. TR9 emerged as a new taxon in lichen symbioses and was successfully isolated and propagated in in vitro culture and thoroughly investigated. Several years of research have confirmed the taxon Trebouxia sp. TR9 to be a model/reference organism for studying mycobiont–photobiont association patterns in lichen symbioses. Trebouxia sp. TR9 is the first symbiotic, lichen-forming microalga for which an exhaustive characterization of cellular ultrastructure, physiological traits, genetic and genomic diversity is available. The cellular ultrastructure was studied by light, electron and confocal microscopy; physiological traits were studied as responses to different abiotic stresses. The genetic diversity was previously analyzed at both the nuclear and organelle levels by using chloroplast, mitochondrial, and nuclear genome data, and a multiplicity of phylogenetic analyses were carried out to study its intraspecific diversity at a biogeographical level and its specificity association patterns with the mycobiont. Here, Trebouxia sp. TR9 is formally described by applying an integrative taxonomic approach and is presented to science as Trebouxia lynnae, in honor of Lynn Margulis, who was the primary modern proponent for the significance of symbiosis in evolution. The complete set of analyses that were carried out for its characterization is provided.