bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Process Parameters and Analysis of Microstructure and Properties of 18Ni300 by Selective Laser Melting
Authors: Ma Yaxin , Gao Yifei , Zhao Lei , Li Dongling , Men Zhengxing
Published: July 2022

In this research, we studied the influence of process parameters on the quality of selective laser melting of 18Ni300 maraging steel. The effects of laser power and scanning speed on the relative density and hardness of 18Ni300 were studied by single-factor experiment and the orthogonal experimental method. The relative optimal process parameters of 18Ni300 were obtained when the layer thickness was 0.03 mm, and the hatch space was 0.1 mm. The microstructures and mechanical properties of the samples formed under different process parameters were characterized. The results showed that the optimal hardness and relative density of the sample were 44.7 HRC and 99.98% when the laser power was 230 W and the scanning speed was 1100 mm/s, respectively; the microstructure of the material was uniform and dense, exhibiting few pores. Some columnar crystals appeared along the boundary of the molten pool due to vertical epitaxial growth. The orientation of fine grains at the boundary of the molten pool was random, and some coarse columnar crystals in the molten pool exhibited a certain orientational preference along the <001> orientation. In the case of optimal process parameters, the SLM-formed 18Ni300 was composed of 99.5% martensite and 0.5% retained austenite; the indentation hardness was distributed in the range of 3.2–5 GPa. The indentation modulus was between 142.8–223.4 GPa, exhibiting stronger fluctuations than the indentation hardness. The sample’s mechanical properties showed obvious anisotropy, while the tensile fracture characteristics exhibited necking. The tensile fracture morphology was ductile, and large equiaxed dimples and holes could be observed in the fiber area, accompanied by tearing characteristics.
Quantitative Distribution Characterization and Correlation Study of Composition, Structure and Hardness of Rim Region in Railway Wheel
Authors: Li Dongling , Wang Haizhou , Shen Xuejing , Lin Shuangping , Feng Haozhou , Peng Ya , Jiang Fan , Zhou Xuefan
Published: July 2022

The railway wheel is the key component of high-speed railway train. To assure the safety in service, higher requirements are put forward in this study for the composition, microstructure uniformity, and comprehensive properties of wheel materials. In this paper, the high throughput quantitative distribution characterization methods of composition, microstructure, inclusions and Vickers hardness of high-speed railway wheel materials based on the spark source original position analysis technique, high throughput scanning electron microscope (SEM) combined with image batch processing technology, and automatic two-dimensional quantitative distribution analysis technique of inclusions and micro hardness have been studied. The distribution trend of the content of nine elements, size and quantity of sulfides and oxides, ferrite area fraction, and Vickers hardness from the wheel tread surface to the radial depth of about 50 mm below the surface has been discussed. The influence of inclusions distribution on the element segregation and the effect of rim-chilling process with different water spraying angle on the distribution of microstructure and micro hardness have been investigated. It was found that unsynchronized cooling on both sides of the rim altered the phase behavior of ferrite and pearlite and obvious inhomogeneity distribution of ferrite appeared, which led to the asymmetrical Vickers hardness in areas near or away from the flange. Based on the quantitative characterization of area fraction and micro hardness on the same location of wheel rim, a statistical mapping relationship between ferrite area fraction and Vickers hardness was established.
Hollow Silica Microparticles Based on Amphiphilic Polyphosphazenes
Authors: Salinas Yolanda , Poscher Vanessa , Brüggemann Oliver , Teasdale Ian
Published: July 2022

Hollow microparticles are important materials, offering a larger surface area and lower density than their solid counterparts. Furthermore, their inner void space can be exploited for the encapsulation and release of guest species in a variety of applications. Herein, we present phosphazene-based silica hollow microparticles prepared via a surfactant-free sol-gel process through self-assembly of the alkoxysilyl-containing polymer in water–ethanol solution. Solely, a silane-derived polyphosphazene was used as the precursor for the microparticle formation, without additional classical silica sources. These novel hollow silica-based microparticles were prepared without surfactant, using a designed amphiphilic polyphosphazene for the particle formation made by two components, a hydrophilic unit consisting of 3-mercaptopropyl(trimethoxysilane), and a hydrophobic unit (dodecanethiol) attached to the double bonds from the poly(allylamine)phosphazene backbone via a thiol-ene photoreaction. Due to these two functionalities, a “vesicle”-like self-assembled structure was formed in the reaction medium, which could be then utilized for the microparticle preparation. The influence of NaOH during the synthesis was shown to affect the size and the wall thickness of the microparticles. This effect may enhance the possibilities to tailor such microparticles for drug delivery purposes or for future controlled release of other substances, such as drugs, fragrances, or anticorrosive pigments.
The Effect of Bi2O3 and Fe2O3 Impurity Phases in BiFeO3 Perovskite Materials on Some Electrical Properties in the Low-Frequency Field
Authors: Casut Cristian , Malaescu Iosif , Marin Catalin Nicolae , Miclau Marinela
Published: July 2022

Pure bismuth ferrite (BFO) and BFO with impurity phases (Bi2O3 or Fe2O3) were synthesized by the hydrothermal method. Complex dielectric permittivity (ε) and electrical conductivity (σ) were determined by complex impedance measurements at different frequencies (200 Hz–2 MHz) and temperatures (25–290) °C. The conductivity spectrum of samples, σ(f), complies with Jonscher’s universal law and the presence of impurity phases leads to a decrease in the static conductivity (σDC); this result is correlated with the increased thermal activation energy of the conduction in impure samples compared to the pure BFO sample. The conduction mechanism in BFO and the effect of impurity phases on σ and ε were analyzed considering the variable range hopping model (VRH). Based on the VRH model, the hopping length (Rh), hopping energy (Wh) and the density of states at the Fermi level (N(EF)) were determined for the first time, for these samples. In addition, from ε(T) dependence, a transition in the electronic structure of samples from a semiconductor-like to a conductor-like behavior was highlighted around 465–490 K for all samples. The results obtained are useful to explain the conduction mechanisms from samples of BFO type, offering the possibility to develop a great variety of electrical devices with novel functions.
Evaporation of As and Sn from Liquid Iron: Experiments and a Kinetic Model during Top-Blown Oxygen Steelmaking Process
Authors: Kim Dong-Hyun , Park Won-Bum , Park Sang-Chae , Kang Youn-Bae
Published: July 2022

Evaporation kinetics of tramp elements (M = As and Sn) in liquid iron were investigated by high-temperature gas–liquid reaction experiments and a phenomenological kinetic model. Residual content of As or Sn in the liquid iron ([pct M]) during the evaporation was measured in the temperature range of 1680 °C to 1760 °C. [pct As] and [pct Sn] decreased faster as the reaction temperature and [pct C]0 increased. Assuming first-order reaction kinetics, the apparent rate constants (kM) were obtained at each reaction temperature and [pct C]0. [pct M] in a liquid iron during the top-blown oxygen steelmaking process was simulated, with an emphasis on enlarging the reaction surface area by forming a large number of liquid iron droplets. The surface area and the droplet generation rate were obtained based on the oxygen-blowing condition. The whole surface area increased up to ∼163 times the initial liquid iron (bath) surface area, due to the generation of the droplets. Using the kM obtained in the present study, the evaporation of M during the top-blown oxygen steelmaking process for 200 tonnes of liquid iron was simulated. For a condition of [pct M]0 = 0.005 (M = As and Sn), As and Sn could be removed from the liquid iron, which was seen to be much improved by the consideration of the droplet generation. However, additional actions are required to improve the evaporation rate, as the evaporation rate in the BOF process was not fast enough to be practically considered.
Design and Analysis of the High-Speed Permanent Magnet Motors: A Review on the State of the Art
Authors: Shen Qiping , Zhou Ziyao , Li Shan , Liao Xinglin , Wang Tao , He Xiaorong , Zhang Jingshan
Published: July 2022

This paper provides an overview of the design and analysis of high-speed PM motors by focusing on prominent issues such as motor losses, temperature rise, rotor strength and vibration. The design challenges of high-speed PM motors are briefly described, and the application of various stator and rotor structures and materials is presented in electromagnetic design. Combined with the temperature distribution of the motor, various heat dissipation measures to suppress the temperature rise are summarized. Strength and dynamics analysis of the rotor are outlined with respect to the safety of rotor operation. The current status of coupled multi-physics domain design used to improve the comprehensive design capability of high-speed PM motors is reviewed. Future directions of technologies related to the design of high-speed PM motors are pointed out.
Blockchain Empowered Smart Home: A Scalable Architecture for Sustainable Smart Cities
Authors: Aldribi Abdulaziz , Singh Aman
Published: July 2022

Emerging growth in technology has rapidly changed our homes and cities. Present homes and cities will be upgraded to smart homes and smart cities in the near future. Various solutions used to build the smart-city network demand a scalable and decentralized solution. This study proposes a blockchain-empowered decentralized and scalable solution for a sustainable smart-city network. The Internet of Things (IoT), fog nodes, permissioned trust chain, smart contract, blockchain, and InterPlanetary file system (IPFS) are deployed to construct a scalable and decentralized solution for a sustainable smart city. Three main public sector departments, i.e., electricity, water supply, and health care, are studied over the proposed solution. The proposed solution is implemented over constrained application protocol (CoAP) and Ethereum blockchain. The performance of the proposed model is evaluated for 1500 devices and over 10,000 records. A total 77.44% improvement is registered during performance evaluation over a scalable environment. The performance evaluation of each case study and collaborative performance evaluation concludes the improvised performance of the proposed solution for scalable and distributed applications. Better performance, scalability, and the distributed nature of the presented model make it suitable for the sustainable smart-city network.
Design and Experience of Mobile Applications: A Pilot Survey
Authors: Sandesara Mudita , Bodkhe Umesh , Tanwar Sudeep , Alshehri Mohammad Dahman , Sharma Ravi , Neagu Bogdan-Constantin , Grigoras Gheorghe , Raboaca Maria Simona
Published: July 2022

With the tremendous growth in mobile phones, mobile application development is an important emerging arena. Moreover, various applications fail to serve the purpose of getting the attention of the intended users, which is determined by their User Interface (UI) and User Experience (UX). As a result, developers often find it challenging to meet the users’ expectations. To date, several reviews have been carried out which explored various aspects of design and the experience of mobile applications using UX/UI. However, many of these existing surveys primarily focused on only some of the issues in isolation but did not consider all the major parameters such as visualisation/graphics, context, user behaviour/emotions/control, usability, adaptability/flexibility, language, and feedback. In our pilot survey, we gathered the preferences and perceptions of a heterogeneous group of concerned people and considered all the aforementioned parameters. These preferences would serve as a reference to mobile application developers, giving them useful insights. Our proposed approach would help mobile application developers and designers focus on the particular UI/UX problems of mobile applications as per their relevant context. A comparative analysis of the various UI and UX factors that determine a mobile application interface is presented in this paper.
One Aggregated Approach in Multidisciplinary Based Modeling to Predict Further Students’ Education
Authors: Ranđelović Milan , Aleksić Aleksandar , Radovanović Radovan , Stojanović Vladica , Čabarkapa Milan , Ranđelović Dragan
Published: July 2022

In this paper, one multidisciplinary-applicable aggregated model has been proposed and verified. This model uses traditional techniques, on the one hand, and algorithms of machine learning as modern techniques, on the other hand, throughout the determination process of the relevance of model attributes for solving any problems of multicriteria decision. The main goal of this model is to take advantage of both approaches and lead to better results than when the techniques are used alone. In addition, the proposed model uses feature selection methodology to reduce the number of attributes, thus increasing the accuracy of the model. We have used the traditional method of regression analysis combined with the well-known mathematical method Analytic Hierarchy Process (AHP). This approach has been combined with the application of the ReliefF classificatory modern ranking method of machine learning. Last but not least, the decision tree classifier J48 has been used for aggregation purposes. Information on grades of the first-year graduate students at the Criminalistics and Police University, Belgrade, after they chose and finished one of the three possible study modules, was used for the evaluation of the proposed model. To the best knowledge of the authors, this work is the first work when considering mining closed frequent trees in case of the streaming of time-varying data.
A Mathematical Study of a Semiconducting Thermoelastic Rotating Solid Cylinder with Modified Moore–Gibson–Thompson Heat Transfer under the Hall Effect
Authors: Kaur Iqbal , Singh Kulvinder , Craciun Eduard-Marius
Published: July 2022

This research aims to investigate photo-thermoelastic interactions in a rotating infinite semiconducting solid cylinder under a high magnetic field acting along its axis with the Hall current effect. The boundary surface is subjected to a variable heat flux generated by an exponential laser pulse. The governing equations are expressed using a new photo-thermoelastic model generalized in the Moore–Gibson–Thompson photo-thermal (MGTPT) heat transfer model for a semiconducting medium. The Moore–Gibson–Thompson (MGT) equation is obtained by introducing a thermal relaxation parameter into the Green–Naghdi (GN III) model. The Laplace transform is utilized to determine the mathematical expressions for the components of displacement, carrier density, temperature field, and thermal stresses in the transformed domain. The numerical inversion technique is used to obtain the expressions in the physical domain. The impacts of thermal relaxations, different theories of thermoelasticity, the Hall current, and rotation on the displacement, temperature, thermal stresses, and carrier density are represented graphically using MATLAB software.
A Model of a Universal Neural Computer with Hysteresis Dynamics for Avionics Problems
Authors: Solovyov Andrey M. , Selvesyuk Nikolay I. , Kosyanchuk Vladislav V. , Zybin Evgeniy Y.
Published: July 2022

The paper proposes a method for implementing a universal neural network processor with hysteresis dynamics. This processor allows a wide range of heterogeneous tasks in real time to be performed without reprogramming and changing their internal structure. Adding hysteresis behavior to the system makes it possible to increase resistance to external influences, the complexity as well as non-linearity of intelligent output. The paper discusses the use of this processor as part of an on-board intelligent avionics system.
A Study on Welding Characteristics, Mechanical Properties, and Penetration Depth of T-Joint Thin-Walled Parts for Different TIG Welding Currents: FE Simulation and Experimental Analysis
Authors: Pan Minghui , Li Yuchao , Sun Siyuan , Liao Wenhe , Xing Yan , Tang Wencheng
Published: July 2022

Considering the effect of heat input of tungsten inert gas (TIG) arc welding for T-joint welding of thin-walled parts of aluminum alloy 6061-T6, here, the welding characteristics are analyzed via the finite element method. The experiments are carried out using scanning electron microscope (SEM), optical microscope (OM), and tensile test of specimens to investigate the microstructure variation of the weld zone (WZ), heat-affected zone (HAZ), and base metal (BM), and the mechanical properties of the T-welded joint. The mechanical properties of the T-welded joint are explored and assessed combined with the tensile test in terms of yield strength, tensile strength, and Vickers hardness. Furthermore, the effects of different welding currents on welding penetration variation under welding deformation are thoroughly investigated, and the appearance of porosity and incomplete fusion defects of T-welded joints are clearly illustrated. The results show that the yield and tensile strength of T-welded joints, respectively, account for less than 37% and 74% of the base metal (BM) strength. Moreover, the welding penetration depth and microstructure of T-welded joints are deeply affected by the welding current. The maximum penetration depth is achieved at about 2.18 mm under the maximum welding current, and partial welding defects emerged, affecting and reducing the mechanical properties of the welded joint. It is expected that these results will provide an analysis foundation for optimization of the welding process, suppression of welding defects, and promotion of mechanical properties for thin-walled parts in the future.
Fetuin-A in Activated Liver Macrophages Is a Key Feature of Non-Alcoholic Steatohepatitis
Authors: Etienne Quentin , Lebrun Valérie , Komuta Mina , Navez Benoît , Thissen Jean-Paul , Leclercq Isabelle A. , Lanthier Nicolas
Published: July 2022

Fetuin-A, a plasma multifunctional protein known to play a role in insulin resistance, is usually presented as a liver secreted protein. However, fetuin-A adipose tissue production has been also described. Here, we evaluated fetuin-A production by the liver and the adipose tissue during metabolic dysfunction-associated fatty liver disease (MAFLD)-non-alcoholic steatohepatitis (NASH) development. Fetuin-A was evaluated by enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), Western blot, and immunofluorescence in male foz−/− mice fed a normal diet (ND) or a high fat diet (HFD) at various timepoints and in MAFLD-NASH patients. Foz−/− mice fed a short-term HFD developed liver steatosis, insulin resistance, and increased circulating levels of fetuin-A compared to ND-fed mice. In mice and patients with NASH, fetuin-A was located not only in healthy or steatotic hepatocytes but also in some macrophages forming lipogranulomas. In both mice and humans, a significant amount of fetuin-A was present in the adipose tissue compared to the liver. However, messenger ribonucleic acid levels and cell culture experiments indicate that fetuin-A is produced by the liver but not by the adipose tissue. In conclusion, fetuin-A is produced by steatotic hepatocytes at early timepoints in MAFLD and correlates with insulin resistance both in mice and humans. In NASH, fetuin-A also co-localizes with activated liver macrophages and could be interpreted as a signal released by damaged hepatocytes.
The Influence of Dietary Factors on the Gut Microbiota
Authors: Nova Esther , Gómez-Martinez Sonia , González-Soltero Rocio
Published: July 2022

There is increasing evidence that diet influences the relationship between gut microbiota and individual health outcomes. Nutrient intake affects the composition of the gut microbial community and provides metabolites that influence the host physiology. Dietary patterns, including macronutrient balance and feeding/fasting cycles which may be manipulated with dietary regimens based on caloric restriction periods, influence the gut homeostasis through its impact on the microbial ecosystem. Along the same line, prebiotic and probiotic ingredients and additives in foods, as well as the degree of food processing have consequences on gut microbiota and the related immune and metabolic response of the human host. Acquiring knowledge of these aspects, especially through an -omics-integral approach, might provide the basis for personalized nutritional interventions directed to avoid dysbiosis and contribute to the prevention of major chronic degenerative diseases. Despite vast scientific evidence supporting the relationship between dietary factors and gut microbiota composition and function, the underlying mechanisms and their potential impact are far from clear. There is a lack of well-designed longitudinal studies performed in target population groups whose dietary patterns can be particularly relevant for their future health, as is the case in infants, pregnant women, or athletes.
The Use of Modified Fe3O4 Particles to Recover Polyphenolic Compounds for the Valorisation of Olive Mill Wastewater from Slovenian Istria
Authors: Peeters Kelly , Miklavčič Višnjevec Ana , Tavzes Črtomir
Published: July 2022

Olive mill waste water (OMWW), a by-product created during the processing of olive oil, contains high amounts of polyphenolic compounds. If put to further use, these polyphenolic compounds could be a valuable resource for the speciality chemical industry. In order to achieve this, isolation of the polyphenolic compounds from OMWW is needed. Several techniques for this process already exist, the most widely used of which is adsorption beds. This research describes new ways of collecting polyphenolic compounds by using unmodified iron oxide (Fe3O4) particles and Fe3O4 modified with silica gel (Fe3O4@C18), citric acid (Fe3O4@CA), and sodium dodecyl sulphate (Fe3O4@SDS). This approach is superior to adsorption beds since it can be used in a continuous system without clogging, while the nano-sized shapes create a high surface area for adsorption. The results of this study show that, if used in a loop system of several adsorption and desorption cycles, (un)modified Fe3O4 has the potential to collect high concentrations of polyphenolic compounds. A combination of different modifications of the Fe3O4 particles is also beneficial, as these combinations can be tailored to allow for the removal of specific polyphenolic compounds.
High-Dispersed V2O5-CuOX Nanoparticles on h-BN in NH3-SCR and NH3-SCO Performance
Authors: Im Han-Gyu , Lee Myeung-Jin , Kim Woon-Gi , Kim Su-Jin , Jeong Bora , Ye Bora , Lee Heesoo , Kim Hong-Dae
Published: July 2022

Typically, to meet emission regulations, the selective catalytic reduction of NOX with NH3 (NH3-SCR) technology cause NH3 emissions owing to high NH3/NOX ratios to meet emission regulations. In this study, V-Cu/BN-Ti was used to remove residual NOX and NH3. Catalysts were evaluated for selective catalytic oxidation of NH3 (NH3-SCO) in the NH3-SCR reaction at 200–300 °C. The addition of vanadium and copper increased the number of Brønsted and Lewis acid sites available for the reaction by increasing the ratio of V5+ and forming Cu+ species, respectively. Furthermore, h-BN was dispersed in the catalyst to improve the content of vanadium and copper species on the surface. NH3 and NOX conversion were 98% and 91% at 260 °C, respectively. Consequently, slipped NH3 (NH3-Slip) emitted only 2% of the injected ammonia. Under SO2 conditions, based on the NH3 oxidation reaction, catalytic deactivation was improved by addition of h-BN. This study suggests that h-BN is a potential catalyst that can help remove residual NOX and meet NH3 emission regulations when placed at the bottom of the SCR catalyst layer in coal-fired power plants.
Self-Supported Co3O4@Mo-Co3O4 Needle-like Nanosheet Heterostructured Architectures of Battery-Type Electrodes for High-Performance Asymmetric Supercapacitors
Authors: Kumar Yedluri Anil , Das Himadri Tanaya , Guddeti Phaneendra Reddy , Nallapureddy Ramesh Reddy , Pallavolu Mohan Reddy , Alzahmi Salem , Obaidat Ihab M.
Published: July 2022

Herein, this report uses Co3O4 nanoneedles to decorate Mo-Co3O4 nanosheets over Ni foam, which were fabricated by the hydrothermal route, in order to create a supercapacitor material which is compared with its counterparts. The surface morphology of the developed material was investigated through scanning electron microscopy and the structural properties were evaluated using XRD. The charging storage activities of the electrode materials were evaluated mainly by cyclic voltammetry and galvanostatic charge-discharge investigations. In comparison to binary metal oxides, the specific capacities for the composite Co3O4@Mo-Co3O4 nanosheets and Co3O4 nano-needles were calculated to be 814, and 615 C g−1 at a current density of 1 A g−1, respectively. The electrode of the composite Co3O4@Mo-Co3O4 nanosheets displayed superior stability during 4000 cycles, with a capacity of around 90%. The asymmetric Co3O4@Mo-Co3O4//AC device achieved a maximum specific energy of 51.35 Wh Kg−1 and power density of 790 W kg−1. The Co3O4@Mo-Co3O4//AC device capacity decreased by only 12.1% after 4000 long GCD cycles, which is considerably higher than that of similar electrodes. All these results reveal that the Co3O4@Mo-Co3O4 nanocomposite is a very promising electrode material and a stabled supercapacitor.
Structural Study of Nano-Clay and Its Effectiveness in Radiation Protection against X-rays
Authors: Sakher Elfahem , Smili Billel , Bououdina Mohamed , Bellucci Stefano
Published: July 2022

With the increasing applications of nuclear technology, radiation protection has become very important especially for the environment and the personnel close to radiation sources. Natural clays can be used potentially for shielding the X-ray radiations. In this study, the correlation between structural parameters and radiation shielding performance of natural clay extracted from Algerian Sahara (Adrar, Reggan, and Timimoune) was investigated. Phase composition and structural parameters (lattice parameters, average crystallite size, and microstrain) were determined by the Rietveld refinements of X-ray diffraction patterns in the frame of HighScore Plus software. The obtained results showed that the studied clays are nanocrystalline (nano-clay) since the calculated crystallite size was ≈3 nm for the feldspar phase. FTIR spectra confirmed the presence of all phases already detected by XRD analysis besides Biotite (around the band at 3558 cm−1). The remaining bands corresponded to absorbed and adsorbed water (3432 cm−1 and 1629 cm−1, respectively) and atmospheric CO2 (2356 cm−1). The shielding properties (mass absorption coefficient—µ/ρ and radiative attenuation rate—RA) for (green-yellow, green, and red) clays of Adrar, (red, white, and white-red) clays of Reggan, and red clay of Timimoune at same energy level were examined. The results of clay samples were compared with each other. The obtained results indicated that the green clay of Adrar exhibited the superior radiation shielding, i.e., 99.8% and 243.4 cm2/g for radiative attenuation rate and mass absorption coefficient, respectively.
Traditional Individual and Environmental Determinants of Healthy Eating in Vihiga County, Western Kenya
Authors: Penafiel Daniela , Termote Celine , Van Damme Patrick
Published: July 2022

Traditional ethnic groups in Kenya are unlikely to eat a healthy and diversified diet due to many individual and environmental factors, which may result in poor health status. Therefore, the determinants of eating behavior need to be identified prior to any public health action. For this study, focus group discussions (15 in total) in a double-layer design were conducted, comprising adult men and women from 5 villages of Vihiga County. Questions explored knowledge; barriers and cues to action toward eating a healthy diet containing a variety of foods; including indigenous food species. We found that healthy eating concepts are known; however, several taboos that restrict food consumption reduce local diet quality in terms of diversity. Nutrition education is a cue to action. We identified several individual and environmental determinants of eating behavior in the studied communities. Public health action should focus on supporting healthy eating behaviors and refining some taboos’ beliefs.
Evidence-Informed Development of a Bundle for Peripheral Intravenous Catheterization in Portugal: A Delphi Consensus Study
Authors: Santos-Costa Paulo , Paiva-Santos Filipe , Sousa Liliana B. , Bernardes Rafael A. , Ventura Filipa , Salgueiro-Oliveira Anabela , Parreira Pedro , Vieira Margarida , Graveto João
Published: July 2022

Contrary to many international settings, there are no clinical guidelines for peripheral intravenous catheter (PIVC) insertion and maintenance in Portugal. We sought to derive an international consensus on a PIVC bundle that could guide Portuguese nurses’ clinical decision-making in this scope. Methods: Two international vascular access specialist groups participated in an online Delphi panel. During the first round, specialists (n = 7) were sent a summary report from a previous observational study conducted in a surgical ward in Portugal. Based on the report findings, specialists were asked to provide five to eight PIVC insertion and maintenance interventions. Then, another set of specialists (n = 7) scored and revised the recommendations until a consensus was reached (≥70% agreement). The PIVC bundle was made available and discussed with the surgical ward’s nurses. Results: After three rounds, a consensus was achieved for five evidence-informed interventions: (i) involve the person and assess the peripheral venous network; (ii) maintain an aseptic no-touch technique; (iii) ensure proper catheter dressing and fixation; (iv) perform catheter flush & lock; (v) test the peripheral venous catheter’s functionality and performance at each shift. Conclusion: The final version of the PIVC bundle achieved consensus among international experts. Despite the positive feedback provided by the ward nurses, future studies are warranted to assess its effectiveness in standardizing PIVC care delivery and its potential implications for care outcomes in Portuguese clinical settings.
Bacteriophage and Bacterial Susceptibility, Resistance, and Tolerance to Antibiotics
Authors: Chen Qingquan , Dharmaraj Tejas , Cai Pamela C. , Burgener Elizabeth B. , Haddock Naomi L. , Spakowitz Andy J. , Bollyky Paul L.
Published: July 2022

Bacteriophages, viruses that infect and replicate within bacteria, impact bacterial responses to antibiotics in complex ways. Recent studies using lytic bacteriophages to treat bacterial infections (phage therapy) demonstrate that phages can promote susceptibility to chemical antibiotics and that phage/antibiotic synergy is possible. However, both lytic and lysogenic bacteriophages can contribute to antimicrobial resistance. In particular, some phages mediate the horizontal transfer of antibiotic resistance genes between bacteria via transduction and other mechanisms. In addition, chronic infection filamentous phages can promote antimicrobial tolerance, the ability of bacteria to persist in the face of antibiotics. In particular, filamentous phages serve as structural elements in bacterial biofilms and prevent the penetration of antibiotics. Over time, these contributions to antibiotic tolerance favor the selection of resistance clones. Here, we review recent insights into bacteriophage contributions to antibiotic susceptibility, resistance, and tolerance. We discuss the mechanisms involved in these effects and address their impact on bacterial fitness.
Model Re-Estimation: An Alternative for Poor Predictive Performance during External Evaluations? Example of Gentamicin in Critically Ill Patients
Authors: Duong Alexandre , Simard Chantale , Williamson David , Marsot Amélie
Published: July 2022

Background: An external evaluation is crucial before clinical applications; however, only a few gentamicin population pharmacokinetic (PopPK) models for critically ill patients included it in the model development. In this study, we aimed to evaluate gentamicin PopPK models developed for critically ill patients. Methods: The evaluated models were selected following a literature review on aminoglycoside PopPK models for critically ill patients. The data of patients were retrospectively collected from two Quebec hospitals, the external evaluation and model re-estimation were performed with NONMEM® (v7.5) and the population bias and imprecisions were estimated. Dosing regimens were simulated using the best performing model. Results: From the datasets of 39 and 48 patients from the two Quebec hospitals, none of the evaluated models presented acceptable values for bias and imprecision. Following model re-estimations, all models showed an acceptable predictive performance. An a priori dosing nomogram was developed with the best performing re-estimated model and was consistent based on recommended dosing regimens. Conclusion: Due to the poor predictive performance during the external evaluations, the latter must be prioritized during model development. Model re-estimation may be an alternative to developing a new model, especially when most known models display similar covariates.
Experimental Study of Transverse Trapping Forces of an Optothermal Trap Close to an Absorbing Reflective Film
Authors: Wang Hao-Dong , Bai Wen , Zhang Bu , Li Bo-Wei , Ji Feng , Zhong Min-Cheng
Published: July 2022

The optothermal manipulation of micro-objects is significant for understanding and exploring the unknown in the microscale word, which has found many applications in colloidal science and life science. In this work, we study the transverse forces of an optothermal trap in front of a gold film, which is an absorbing reflective surface for the incident laser beam. It is demonstrated that optothermal forces can be divided into two parts: optical force of a standing-wave trap, and thermal force of a thermal trap. The optical force of the standing-wave trap can be obtained by measuring the optical trapping force close to a non-absorbing film with same reflectance. The thermal force can be obtained by subtracting the optical force of the standing-wave trap from the total trapping force of the optothermal trap close to the gold film. The results show that both optical and thermal trapping forces increase with laser power increasing. The optical trapping force is larger than the thermal trapping force, which is composed of convective drag force and thermophoretic force. Further experiment is run to study the composition of thermal force. The result shows that the convective flow is generated later than the thermophoretic flow. The results proposed here are useful for enabling users to optimize optothermal manipulation method for future applications.
Relationship between the Antifungal Activity of Chitosan–Capsaicin Nanoparticles and the Oxidative Stress Response on Aspergillus parasiticus
Authors: Hernández-Téllez Cynthia Nazareth , Luque-Alcaraz Ana Guadalupe , Núñez-Mexía Sahily Alejandra , Cortez-Rocha Mario Onofre , Lizardi-Mendoza Jaime , Rosas-Burgos Ema Carina , Rosas-Durazo Aarón de Jesús , Parra-Vergara Norma Violeta , Plascencia-Jatomea Maribel
Published: July 2022

The fungus Aspergillus parasiticus is a contaminant in agricultural crops and its eradication involves the indiscriminate use of harmful synthetic pesticides. In the search for antifungal agents of natural origin, chitosan (Q) and capsaicin (C) are coupled in the form of nanoparticles (Np), which can possess a direct application under specific conditions. Due to their small size, Np can cross through the cell wall, taking the cells into a pro-oxidant environment known as “oxidative stress”, which presents when the reactive oxygen species (ROS) surpass the number of antioxidants in the cell. In the present investigation, nanoparticles of chitosan (Np Q) and nanoparticles of chitosan-capsaicin (Np QC) with an average diameter of 44.8 ± 20.6 nm and 111.1 ± 14.1 nm, respectively, were synthesized, and there was a zeta potential of + 25.6 ± 0.7 mV and + 26.8 ± 6.1 mV, respectively. The effect of the concentration of Np Q (A, B, C, and D), of Np QC (A, B, C, and D), and capsaicin in a solution (control) was evaluated on the viability of the spores, the accumulation of intracellular ROS, and the morphometric changes of A. parasiticus. Acute toxicity of the Np was determined utilizing bioassays with Artemia salina, and acute phytotoxicity was evaluated in lettuce seeds (Lactuca sativa). According to ROS results, capsaicin (control) did not induce oxidative stress in the cell; otherwise, it was observed to have an elevated (p < 0.05) accumulation of ROS when the concentration of Np Q increased. For both, Np Q and Np QC, an inverse physiological pattern relating spore viability and ROS accumulation in the fungus was found; the viability of spores decreased as the ROS accumulation increased. The spore viability of A. parasiticus diminished upon increasing the concentration of chitosan (0.3–0.4 mg/mL) in the Np, while the intracellular accumulation of ROS increased proportionally to the concentration of the nanomaterials in the treatments of Np Q and Np QC. On the other hand, Np QC presented a lower (p < 0.05) toxicological effect in comparison with Np Q, which indicates that the incorporation of bioactive compounds, such as capsaicin, into nanoparticles of chitosan is a strategy that permits the reduction of the toxicity associated with nanostructured materials.
Advances in the Utilization of Tea Polysaccharides: Preparation, Physicochemical Properties, and Health Benefits
Authors: Wang Qian , Yang Xiaoyan , Zhu Changwei , Liu Guodong , Sun Yujun , Qian Lisheng
Published: July 2022

Tea polysaccharide (TPS) is the second most abundant ingredient in tea following tea polyphenols. As a complex polysaccharide, TPS has a complex chemical structure and a variety of bioactivities, such as anti-oxidation, hypoglycemia, hypolipidemic, immune regulation, and anti-tumor. Additionally, it shows excellent development and application prospects in food, cosmetics, and medical and health care products. However, numerous studies have shown that the bioactivity of TPS is closely related to its sources, processing methods, and extraction methods. Therefore, the authors of this paper reviewed the relevant recent research and conducted a comprehensive and systematic review of the extraction methods, physicochemical properties, and bioactivities of TPS to strengthen the understanding and exploration of the bioactivities of TPS. This review provides a reference for preparing and developing functional TPS products.
Rutting Behaviour of Geopolymer and Styrene Butadiene Styrene-Modified Asphalt Binder
Authors: Hamid Abdulrahman , Baaj Hassan , El-Hakim Mohab
Published: July 2022

Modifying asphalt binders is an effective method of improving the performance of asphalt pavement, such as its resistance to rutting. However, because modification changes the behaviour of binders, substantial laboratory testing is required before field application to determine the best mixtures. This research aimed to evaluate the impacts of temperature, stresses, polymer type, and modification rate on the rutting behaviour of the asphalt binder modified with fly-ash-based geopolymer (GF), styrene butadiene styrene (SBS), and a combination of SBS and GF. The rheological properties of asphalt binders were investigated using the frequency sweep test at various temperatures. Additionally, the multiple stress creep recovery test was conducted at various temperatures and stresses to calculate the non-recoverable creep compliance (Jnr) and the percent strain recovery (R). The rutting resistance of asphalt mixture was assessed using the Hamburg wheel rut test. The results revealed that the asphalt binder with 8% geopolymer (8%GF) exhibited the best response in terms of complex shear modulus (G*), rutting factor (G*/sinδ), R, and Jnr compared to the 4%GF and 12%GF at different temperatures. Another interesting finding is that GF’s use in the hybrid binder (2%SBS + 8%GF) led to a significant increase in the shear complex modulus and a decrease in the phase angle compared to the binder modified with 2%SBS. The geopolymer decreased the binder’s sensitivity to temperature for both unaged and RTFO asphalt binders. The hybrid binder would also improve strain recovery under high stress and temperatures and the ability to withstand severe traffic loads. Furthermore, there is a crucial relationship between temperature and Jnr, which could help asphalt pavement designers select suitable modifiers considering the local climate and traffic volume.
Comparative Static Analysis on the Agricultural Mechanization Development Levels in China’s Provincial Areas
Authors: Wang Sheng , Sun Yanhong , Yang Chen
Published: July 2022

The foundation of the national economy is agriculture, agricultural modernization is the symbol of national modernization and agricultural mechanization is an important symbol of agricultural modernization. In this paper, the authors conducted an analysis of the agricultural mechanization levels of 31 provincial areas in China. In order to assess the agricultural mechanization levels of the provincial areas in China as accurately as possible, the authors adopted indicators in the year 2005, the year 2010 and the year 2015, and used the comparative static analysis method to observe the dynamic changes in the data over the three years. Eight items, including total agricultural mechanization power/grain output (10 million watts/10 k tons), number of large and medium-sized tractors/grain output (pcs/10 k tons), tractor plowing area/grain output (k hectares/10 k tons), total input of agricultural mechanization business operation/grain output (million yuan/10 k tons), total income of agricultural mechanization business operation/grain output (million yuan/10 k tons), and fuel consumption for agricultural production/grain output (hundred tons/10 k tons), were used as assessment indicators. With the gray weighted cluster assessment instrument, 31 provincial areas of China were classified into five gray categories at high development level, relatively high development level, medium development level, medium to low development level and low development level. An objective, scientific and comprehensive assessment of the cluster results was conducted in an effort to better provide references for the authorities to draft relevant policies and measures.
A Review on Risk Management of Coronavirus Disease 19 (COVID-19) Infection in Dental Practice: Focus on Prosthodontics and All-Ceramic Materials
Authors: Sorrentino Roberto , Basilicata Michele , Ruggiero Gennaro , Mauro Maria Irene Di , Leone Renato , Bollero Patrizio , Zarone Fernando
Published: July 2022

Background: A novel β-coronavirus infection (COVID-19) was first detected in Wuhan city, spreading rapidly to other countries and leading to a pandemic. Dental professionals and patients are exposed to a high risk of COVID-19 infection, particularly in the prosthodontic practice, because of the bio-aerosol produced during teeth preparation with dental handpieces and the strict contact with oral fluids during impression making. This paper aimed to provide an overview to limit the risk of transmission of COVID-19 infections during prosthetic procedures in dental offices. Methods: An electronic search was conducted on the electronic databases of PubMed/Medline, Google Scholar, Embase, Scopus, Dynamed, and Open Grey with the following queries: (COVID-19) AND/OR (SARS-CoV-2) AND/OR (Coronavirus) AND/OR (contaminated surface) AND/OR (cross-infection) AND/OR (Prosthodontics) AND/OR (dental ceramic) AND/OR (glass-ceramic). A manual search was performed as well. Results: From the 1023 collected records, 32 papers were included. Conclusions: Dental offices are at high risk of spreading SARS-CoV-2 infection due to the close contact with patients and continuous exposure to saliva during dental procedures. Therefore, pre-check triages via telephone, decontamination, the disinfection of impressions, the sterilization of scanner tips, and the use of specific personal protective equipment, dental high-speed handpieces with dedicated anti-retraction valves, and effective mouthwashes are strongly recommended.
Examining and Improving the Gender and Language DIF in the VERA 8 Tests
Authors: Temel Güler Yavuz , Rietz Christian , Machunsky Maya , Bedersdorfer Regina
Published: July 2022

The purpose of this study was to examine and improve differential item functioning (DIF) across gender and language groups in the VERA 8 tests. We used multigroup concurrent calibration with full and partial invariance based on the Rasch and two-parameter logistic (2PL) models, and classified students into proficiency levels based on their test scores and previously defined cut scores. The results indicated that some items showed gender- and language-specific DIF when using the Rasch model, but we did not detect large misfit items (suspected as DIF) when using the 2PL model. When the item parameters were estimated using the 2PL model with partial invariance assumption (PI-2PL), only small or negligible misfit items were found in the overall tests for both groups. It is argued in this study that the 2PL model should be preferred because both of its approaches provided less bias. However, especially in the presence of unweighted sample sizes of German and non-German students, the non-German students had the highest misfit item proportions. Although the items with medium or small misfit did not have a significant effect on the scores and performance classifications, the items with large misfit changed the proportions of students at the highest and lowest performance levels.
Marina Pak (c. 1572–1636): An Attempted Reconstruction of Her Years in the Philippines
Authors: Wong Hayoung
Published: July 2022

Marina Pak (c. 1572–1636) entered Christian history as Korea’s first significantly cloistered individual, but researchers know almost nothing about her twenty-two years in the Philippines because of the scarce primary source testimonies. On the other hand, through interdisciplinary reflections on Marina’s pluralistic religious background, the influence of the Japanese state, the significance of the Pasig River, and her relationship in the Philippines with Miyako no Bikuni foundress Naitō Julia (c. 1566–1627), one can reconstruct the steps that Marina might have undertaken to navigate a Christian vocation in a foreign land. This article explores the ways in which Marina might have tried to reconcile three different cultural factors (the Korean identity of her birth, Japanese influences arising from her involuntary sojourn in Japan, and the Filipino culture of her final destination), and despite the tentative nature of the study’s conclusions, these findings may offer paths for future scholars to follow.