bluuebunny/crossref_metadata_2025 huggingface dataset:
Xeno-Estrogenic Pesticides and the Risk of Related Human Cancers
Authors: Kumar Vivek , Yadav Chandra Shekhar , Banerjee Basu Dev
Published: November 2022

In recent decades, “environmental xenobiotic-mediated endocrine disruption”, especially by xeno-estrogens, has gained a lot of interest from toxicologists and environmental researchers. These estrogen-mimicking chemicals are known to cause various human disorders. Pesticides are the most heavily used harmful xenobiotic chemicals around the world. The estrogen-mimicking potential of the most widely used organochlorine pesticides is well established. However, their effect is not as clearly understood among the plethora of effects these persistent xenobiotics are known to pose on our physiological system. Estrogens are one of the principal risk modifiers of various disorders, including cancer, not only in women but in men as well. Despite the ban on these xenobiotics in some parts of the world, humans are still at apparent risk of exposure to these harmful chemicals as they are still widely persistent and likely to stay in our environment for a long time owing to their high chemical stability. The present work intends to understand how these harmful chemicals may affect the risk of the development of estrogen-mediated human cancer.
Functional Profile of Older Adults Hospitalized in Rehabilitation Units of the National Network of Integrated Continuous Care of Portugal: A Longitudinal Study
Authors: Fonseca César , Ramos Ana , Pinho Lara Guedes , Morgado Bruno , Oliveira Henrique , Lopes Manuel
Published: November 2022

Background: The success of healthy aging depends on the ability of countries to study and act on frailty in the elderly, control chronic diseases, improve functional capacity and prevent cognitive decline and social interaction. Aim: (1) to evaluate the functional profile of older adults hospitalized in a Unit of the National Network of Integrated Continuous Care of Portugal; and (2) to assess the relationship between functional profile and age, gender, level of education and emotional state. Methods: Longitudinal study with a population of 59,013 older adults (65 years or older) hospitalized in Medium-Term Care and Rehabilitation Units in Portugal. Results: Older age (≥85 years), no school attendance, low body mass index and presence of sad or depressed mood were predictive factors for a deficit in functional capacity. We identified significant improvements in rehabilitation, but after 210 days of hospitalization, older people incurred a loss of functionality. Total compensation needs were typified by severe deficits in self-care and functional capacity: 47.1%. A moderate deficit was present in 43.1%, and a slight self-care and functional deficit occurred in 9.8% of the individuals. Conclusions: Knowing the determinants of functional capacity and self-care needs will make it possible to define priority intervention groups and implement quality and financing models based on gains in functionality.
Mindsponge-Based Reasoning of Households’ Financial Resilience during the COVID-19 Crisis
Authors: Nguyen Minh-Hoang , Khuc Quy Van , La Viet-Phuong , Le Tam-Tri , Nguyen Quang-Loc , Jin Ruining , Nguyen Phuong-Tri , Vuong Quan-Hoang
Published: November 2022

The COVID-19 crisis was remarkable because no global recession model could predict or provide early notice of when the coronavirus pandemic would happen and damage the global economy. Resilience to financial shocks is crucial for households as future crises like COVID-19 are inevitable. Therefore, the current study aims to examine the effects of financial literacy and accessibility to financial information on the financial resilience of Vietnamese households through the lens of an information-processing perspective. The Bayesian Mindsponge Framework (BMF) analytics was employed on a dataset of 839 samples for the investigation. We found that households of respondents with better financial knowledge and investment skills are less likely to be financially affected during the peak of the COVID-19 crisis, but the effect of investment skills is weakly reliable. Accessibility to financial information through informal sources (having a household member working in the financial sector) and formal sources (participating in a financial course) is positively associated with the respondents’ financial knowledge and investment skills. This finding suggests that the spillover effect of financial knowledge and skills among residents exists, leading to better resilience toward financial shocks. However, if the financial information is inaccurate, it might lead to misinformation, false beliefs, and poor economic decisions on a large scale.
Developing a Model of Insurance Securitisation in Iranian Environmental Conditions
Authors: Peivandi Mahshid , Zeynali Mehdi , Salehi Mahdi , Paytakhti Oskooe Ali , Badavar Nahandi Younes
Published: November 2022

As a growing industry in Iran, the insurance industry has dramatically grasped researchers’ and managers’ attention. Among the various issues in this industry, measuring and evaluating the efficiency and performance of its units and branches has always been considered by relevant experts because such evaluation can help us take adequate steps to improve this area. Through securitisation, insurance companies may mitigate the cost of their capital, increase the return on equity, and improve other metrics that affect their operating performance. Securitisation increases capital productivity in the insurance industry. Therefore, the present study was conducted in 2020 to review and develop a model of insurance securitisation in Iran. The present study is exploratory research. Thus, 13 experts and commentators in insurance securities were interviewed. Second, based on the theme analysis, the content of the interviews was analysed, and a proposed model was developed. Then, according to the obtained model, a questionnaire was designed and distributed among insurance industry experts. Two concepts of validity and reliability were used to validate the questionnaire. Based on the model, 10 main factors were identified as influencing insurance securitisation. Insurance securitisation, management of Iran’s environmental conditions, the role of the capital market in insurance, financing, economic development, optimal risk management, risk transfer process in insurance securitisation, investment culture, support of regulatory bodies and facilities in the securities issuance process, utilisation of technical knowledge and specialised human resources are the factors identified in the research. The results showed that all these factors identified from the interviews were confirmed, and the model was sufficiently valid.
Dynamic Assessment Identifies Morphosyntactic Deficits in Mono- and Bilingual Children with Developmental Language Disorder
Authors: Hadjadj Olivia , Kehoe Margaret , Delage Hélène
Published: November 2022

Dynamic Assessment (DA) is recommended for testing bilinguals as it tests the child’s learning potential and not her or his previously acquired language knowledge. Thus, it allows language difficulties to be distinguished from difficulties related to a lack of L2 exposure. This study presents the findings of DA of morphosyntax in French-speaking monolingual and bilingual children, both Typically Developing (TD) and with Developmental Language Disorder (DLD). We examined whether DA was able to distinguish TD from DLD in children, irrespective of their linguistic group (mono- versus bilingual). Morphosyntactic skills were assessed in a sample of 37 children with DLD (19 bilinguals) and 42 with TD (18 bilinguals), aged from 5 to 12. We assessed six syntactic structures: simple sentences (SVO) in present and past tense, subject relatives, accusative clitic pronouns, passives, and object relatives. We provided graduated prompts if children were not able to produce the target sentences. The results confirmed the accuracy of our morphosyntactic task to disentangle children with TD from children with DLD, regardless of their linguistic group. Moreover, cutoffs for each structure as well as for the total score, as determined via ROC curves, indicated high sensitivity and specificity for children with DLD who had a documented morphosyntactic deficit.
Development of a CT Image Analysis Model for Cast Iron Products Based on Artificial Intelligence Methods
Authors: Tchórz Adam , Korona Krzysztof , Krzak Izabela , Bitka Adam , Książek Marzanna , Jaśkowiec Krzysztof , Małysza Marcin , Głowacki Mirosław , Wilk-Kołodziejczyk Dorota
Published: November 2022

This paper presents an assessment of the possibility of using digital image classifiers for tomographic images concerning ductile iron castings. The results of this work can help the development of an efficient system suggestion allowing for decision making regarding the qualitative assessment of the casting process parameters. Special attention should be focused on the fact that automatic classification in the case of ductile iron castings is difficult to perform. The biggest problem in this aspect is the high similarity of the void image, which may be a sign of a defect, and the nodular graphite image. Depending on the parameters, the tests on different photos may look similar. Presented in this article are test scenarios of the module analyzing two-dimensional tomographic images focused on the comprehensive assessment by convolutional neural network models, which are designed to classify the provided image. For the purposes of the tests, three such models were created, different from each other in terms of architecture and the number of hyperparameters and trainable parameters. The described study is a part of the decision-making system, supporting the process of qualitative analysis of the obtained cast iron castings.
Research Progress of Wide Tunable Bragg Grating External Cavity Semiconductor Lasers
Authors: Li Xuan , Shi Junce , Wei Long , Ding Keke , Ma Yuhang , Sun Kangxun , Li Zaijin , Qu Yi , Li Lin , Qiao Zhongliang , Liu Guojun , Zeng Lina , Xu Dongxin
Published: November 2022

In this paper, we review the progress of wide tunable Bragg grating external cavity semiconductor lasers (BG-ECSLs). We concentrate on BG-ECSLs based on the wide tunable range for multicomponent detection. Wide tunable BG-ECSLs have many important applications, such as wavelength-division multiplexing (WDM) systems, coherent optical communications, gas detection and atom cooling. Wide tunability, narrow linewidth and a high side-mode suppression ratio BG-ECSLs have attracted much attention for their merits. In this paper, three main structures for achieving widely tunable, narrow linewidth, high side-mode suppression ratio BG-ECSLs are reviewed and compared in detail, such as the volume Bragg grating (VBG) structure, fiber Bragg grating (FBG) structure and waveguide Bragg grating (WBG) structure of ECSLs. The advantages and disadvantages of different structures of BG-ECSLs are analyzed. The results show that WBG-ECSLs are a potential way to realize the integration, small size, wide tuning range, stable spectral output and high side-mode suppression ratio laser output. Therefore, the use of WBG as optical feedback elements is still the mainstream direction of BG-ECSLs, and BG-ECSLs offer a further new option for multicomponent detection and multi-atoms cooling.
Multi-Function Reflective Vector Light Fields Generated by All-Dielectric Encoding Metasurface
Authors: Wang Qingyu , Li Chenxia , Fang Bo , Jing Xufeng
Published: November 2022

Traditional optics usually studies the uniform polarization state of light. Compared with uniform vector beams, non-uniform vector beams have more polarization information. Most of the research on generating cylindrical vector beams using metasurfaces focuses on generating transmitted beams using the geometric phase. However, the geometric phase requires the incident light to be circularly polarized, which limits the design freedom. Here, an all-dielectric reflective metasurface is designed to generate different output light according to the different polarization states of the incident light. By combining the two encoding arrangements of the dynamic phase and the geometric phase, the output light is a radial vector beam when the linearly polarized light is incident along the x-direction. Under the incidence of linearly polarized light along the y-direction, the generated output light is an azimuthal vector beam. Under the incidence of left-handed circularly polarized light, the generated output light is a vortex beam with a topological charge of −1. Under the incidence of right-handed circularly polarized light, the generated output light is a vortex beam with a topological charge of +1. The proposed reflective metasurface has potential applications in generating vector beams with high integration.
Effect of Contact Point of Wire Ring on Cooling Behavior during Stelmor Cooling
Authors: Hwang Joong-Ki
Published: November 2022

The influence of the contact point of wire rod on the inhomogeneity of cooling behavior within wire ring was investigated to reveal the fundamental cooling mechanism of wire rod during the Stelmor cooling process. A hotspot, a relatively high-temperature region within wire ring compared with other regions, was generated in both the central (WRc) and edge (WRe) regions of the wire ring. The WRe exhibited hotspots regardless of ring configuration. Meanwhile, the WRc exhibited hotspots with an inline arrangement; otherwise, no hotspot occurred in the WRc with a staggered arrangement. Compared with the middle regions of the wire ring, hotspots easily occurred at both the WRc and WRe due to the low-contact angle of the two wire rings. Moreover, the possibility of hotspot formation increased with increasing wire diameter due to the high-contact area and load caused by the weight of the wire rod. This is the primary reason why the WRc with a large diameter had hotspots despite the large ring pitch. Three solutions were suggested to improve the homogeneity in the mechanical properties within wire ring.
Development of Root Caries Prevention by Nano-Hydroxyapatite Coating and Improvement of Dentin Acid Resistance
Authors: Iwasaki Miyu , Satou Ryouichi , Sugihara Naoki
Published: November 2022

There is no established method for optimizing the use of dentin to prevent root caries, which are increasing in the elderly population. This study aimed to develop a new approach for root caries prevention by focusing on bioapatite (BioHap), a new biomaterial, combined with fluoride. Bovine dentin was used as a sample, and an acid challenge was performed in three groups: no fluoride (control group), acidulated phosphate fluoride treatment (APF group), and BioHap + APF treatment (BioHap group). After applying the new compound, the acid resistance of dentin was compared with that of APF alone. The BioHap group had fewer defects and an increased surface hardness than the APF group. The BioHap group had the smallest lesion depth and least mineral loss among all groups. Using a scanning electron microscope in the BioHap group showed the closure of dentinal tubules and a coating on the surface. The BioHap group maintained a coating and had higher acid resistance than the APF group. The coating prevents acid penetration, and the small particle size of BioHap and its excellent reactivity with fluoride are thought to have contributed to the improvement of acid resistance in dentin. Topical fluoride application using BioHap protects against root caries.
Rheological Investigation of Welding Waste-Derived Graphene Oxide in Water-Based Drilling Fluids
Authors: Ikram Rabia , Jan Badrul Mohamed , Ahmad Waqas , Sidek Akhmal , Khan Mudasar , Kenanakis George
Published: November 2022

Throughout the world, the construction industry produces significant amounts of by-products and hazardous waste materials. The steel-making industry generates welding waste and dusts that are toxic to the environment and pose many economic challenges. Water-based drilling fluids (WBDF) are able to remove the drill cuttings in a wellbore and maintain the stability of the wellbore to prevent formation damage. To the best of our knowledge, this is the first study that reports the application of welding waste and its derived graphene oxide (GO) as a fluid-loss additive in drilling fluids. In this research, GO was successfully synthesized from welding waste through chemical exfoliation. The examination was confirmed using XRD, FTIR, FESEM and EDX analyses. The synthesized welding waste-derived GO in WBDF is competent in improving rheological properties by increasing plastic viscosity (PV), yield point (YP) and gel strength (GS), while reducing filtrate loss (FL) and mud cake thickness (MCT). This study shows the effect of additives such as welding waste, welding waste-derived GO and commercial GO, and their amount, on the rheological properties of WBDF. Concentrations of these additives were used at 0.01 ppb, 0.1 ppb and 0.5 ppb. Based on the experiment results, raw welding waste and welding waste-derived GO showed better performance compared with commercial GO. Among filtration properties, FL and MCT were reduced by 33.3% and 39.7% with the addition of 0.5 ppb of raw welding-waste additive, while for 0.5 ppb of welding waste-derived GO additive, FL and MCT were reduced by 26.7% and 20.9%, respectively. By recycling industrial welding waste, this research conveys state-of-the-art and low-cost drilling fluids that aid in waste management, and reduce the adverse environmental and commercial ramifications of toxic wastes.
Study on the Magnetic Noise Characteristics of Amorphous and Nanocrystalline Inner Magnetic Shield Layers of SERF Co-Magnetometer
Authors: Liu Ye , Gao Hang , Ma Longyan , Quan Jiale , Fan Wenfeng , Xu Xueping , Fu Yang , Duan Lihong , Quan Wei
Published: November 2022

With the widespread use of magneto-sensitive elements, magnetic shields are an important part of electronic equipment, ultra-sensitive atomic sensors, and in basic physics experiments. Particularly in Spin-exchange relaxation-free (SERF) co-magnetometers, the magnetic shield is an important component for maintaining the SERF state. However, the inherent noise of magnetic shield materials is an important factor limiting the measurement sensitivity and accuracy of SERF co-magnetometers. In this paper, both amorphous and nanocrystalline materials were designed and applied as the innermost magnetic shield of an SERF co-magnetometer. Magnetic noise characteristics of different amorphous and nanocrystalline materials used as the internal magnetic shielding layer of the magnetic shielding system were analyzed. In addition, the effects on magnetic noise due to adding aluminum to amorphous and nanocrystalline materials were studied. The experimental results show that compared with an amorphous material, a nanocrystalline material as the inner magnetic shield layer can effectively reduce the magnetic noise and improve the sensitivity and precision of the rotation measurement. Nanocrystalline material is very promising for inner shield composition in SERF co-magnetometers. Furthermore, its ultra-thin structure and low cost have significant application value in the miniaturization of SERF co-magnetometers.
Attempt to Optimize the Corrosion Resistance of HRB400 Steel Rebar with Cr and RE
Authors: Liu Tao , Li Nannan , Liu Chao , Li Jingshe , Zhang Tianyi , Cheng Xuequn , Yang Shufeng
Published: November 2022

The corrosion resistance of the HRB400 steel rebar alloyed with Cr and rare earths (RE) was systematically studied from two aspects, including the properties of the passive film and the protectiveness of the rust layer. The results presented that Cr increased the corrosion resistance of the steel rebar through stabilizing the passive film and was not involved in the formation of corrosion pits, while the pitting corrosion was initiated by the dissolution of (RE)2O2S inclusion, resulting in the local acidification at the bottom of the corrosion pits, which decreased the stability of the passive film. As for the long-term corrosion process, both Cr and RE decreased the corrosion rate of the steel rebar, which was related to the promotion effect on the formation of α-FeOOH in the rust layer from Cr and RE.
Microstructure Evolution and Mechanical Properties of Ferrite–Austenite Duplex Fe-Mn-Al-(Cu)-C Steel under Different Annealing Temperatures
Authors: Yan Xiang , Wu Yiming , Zhang Minghe , Liu Songsong , Sun Lihui , Feng Yunli
Published: November 2022

The effect of Cu addition and the intercritical annealing (IA) temperature on the microstructural evolution and mechanical properties of Fe-0.4C-7Mn-4Al (wt%) was investigated via scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and nanoindentation tests. The results showed that the volume fraction and the average grain size of austenite, and the fraction of high angle grain boundaries, increased with IA temperature increase in the range of 650 °C to 710 °C. The addition of Cu facilitates the formation of Cu-rich nanoparticles, raises the volume fraction of austenite, and delays the recrystallization of austenite. As IA temperature increased, the yield strength (YS), ultimate tensile strength (UTS), and Lüders bands strain (LBS) decreased in both experimental steels. The Cu addition not only increases the YS of medium Mn steel but also benefits the decrease of LBS. The best comprehensive mechanical properties were obtained at the IA temperature of 690 °C in the studied steel, with Cu addition. According to nanoindentation experiments, the Cu addition raises the hardness of ferrite and austenite from 4.7 GPa to 6.3 GPa and 7.4 GPa to 8.5 GPa, respectively, contributing to the increase of YS of medium-Mn steel.
Effect of TiO2 Additives on the Stabilization of h-YbFeO3 and Promotion of Photo-Fenton Activity of o-YbFeO3/h-YbFeO3/r-TiO2 Nanocomposites
Authors: Tikhanova Sofia , Seroglazova Anna , Chebanenko Maria , Nevedomskiy Vladimir , Popkov Vadim
Published: November 2022

Nanostructured hexagonal rare-earth orthoferrites (h-RfeO3, R = Sc, Y, Tb-Lu) are well known as a highly effective base for visible-light-driven heterojunction photocatalysts. However, their application is limited by metastability, leading to difficulties in synthesis due to the irreversible transformation to a stable orthorhombic structure. In this work, we report on a simple route to the stabilization of h-YbFeO3 nanocrystals by the synthesis of multiphase nanocomposites with titania additives. The new I-type heterojunction nanocomposites of o-YbFeO3/h-YbFeO3/r-TiO2 were obtained by the glycine–nitrate solution combustion method with subsequent heat treatment of the products. An increase in the mole fraction of the h-YbFeO3 phase in nanocomposites was found with the titanium addition, indicating its stabilizing effect via limiting mass transfer over heat treatment. The complex physicochemical analysis shows multiple contacts of individual nanocrystals of o-YbFeO3 (44.4–50.6 nm), h-YbFeO3 (7.5–17.6 nm), and rutile r-TiO2 (~5 nm), confirming the presence of the heterojunction structure in the obtained nanocomposite. The photocatalytic activity of h-YbFeO3/o-YbFeO3/r-TiO2 nanocomposites was evaluated by the photo-Fenton degradation of the methyl violet under visible light (λ ≥ 400 nm). It was demonstrated that the addition of 5 mol.% of TiO2 stabilizes h-YbFeO3, which allowed us to achieve a 41.5 mol% fraction, followed by a three-time increase in the photodecomposition rate constant up to 0.0160 min−1.
Solubilization and Thermodynamic Analysis of Isotretinoin in Eleven Different Green Solvents at Different Temperatures
Authors: Shakeel Faiyaz , Haq Nazrul , Mahdi Wael A. , Alsarra Ibrahim A. , Alshehri Sultan , Alenazi Miteb , Alwhaibi Abdulrahman
Published: November 2022

The solubilization and thermodynamic analysis of isotretinoin (ITN) in eleven distinct green solvents, such as water, methyl alcohol (MeOH), ethyl alcohol (EtOH), 1-butyl alcohol (1-BuOH), 2-butyl alcohol (2-BuOH), ethane-1,2-diol (EG), propane-1,2-diol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), Transcutol-HP (THP), and dimethyl sulfoxide (DMSO) was studied at several temperatures and a fixed atmospheric pressure. The equilibrium approach was used to measure the solubility of ITN, and the Apelblat, van’t Hoff, and Buchowski–Ksiazczak λh models were used to correlate the results. The overall uncertainties were less than 5.0% for all the models examined. The highest ITN mole fraction solubility was achieved as 1.01 × 10−1 in DMSO at 318.2 K; however, the least was achieved as 3.16 × 10−7 in water at 298.2 K. ITN solubility was found to be enhanced with an increase in temperature and the order in which it was soluble in several green solvents at 318.2 K was as follows: DMSO (1.01 × 10−1) > EA (1.73 × 10−2) > PEG-400 (1.66 × 10−2) > THP (1.59 × 10−2) > 2-BuOH (6.32 × 10−3) > 1-BuOH (5.88 × 10−3) > PG (4.83 × 10−3) > EtOH (3.51 × 10−3) > EG (3.49 × 10−3) > MeOH (2.10 × 10−3) > water (1.38 × 10−6). ITN–DMSO showed the strongest solute–solvent interactions when compared to the other ITN and green solvent combinations. According to thermodynamic studies, ITN dissolution was endothermic and entropy-driven in all of the green solvents tested. The obtained outcomes suggested that DMSO appears to be the best green solvent for ITN solubilization.
Elastoplastic Analysis of Circular Steel Tube of CFT Stub Columns under Axial Compression
Authors: Zhao Hua , Han Rui , Yuan Weiguang , Zhao Shichun , Sun Yuping
Published: November 2022

Composite action between the components of the concrete-filled steel tube (CFT) is complex and it is difficult to accurately obtain the experimental relationship between the steel tube and the core concrete of CFT columns. The triaxially stressed core concrete has been studied by hydrostatic test in past research, while little research has been focused on the mechanical behavior of steel tube of CFT columns. It is difficult to obtain the experimental constitutive relationship of the steel tube of CFT columns to reflect the real-time influence of biaxial stress state and local buckling of steel plate on the steel tube. To clarify the mechanical behavior of the steel tube of CFT columns, this paper proposed an elastoplastic analytical method considering biaxial stress state and local buckling of steel tube to obtain the stress–strain curve of the steel tube. This method applied the Hook’s law and the plasticity theory to interpret the information conveyed by the measured vertical and hoop strain histories of the steel tube. To verify its effectiveness, 11 circular concrete-filled steel tube stub columns were fabricated and tested under axial compression. Superposition results of the axial load–strain of steel tube and core concrete were compared against the experimental curves. The widely used Sakino–Sun model of the confined concrete was adopted to calculate the axial load–strain curve of the core concrete. Satisfactory agreements between the calculated and experimental results confirmed the rationality of the proposed method in tracing the constitutive relation of the biaxially stressed steel tube even after the occurrence of the local buckling. The obtained stress–strain relationship is critical for establishment of mathematical constitutive model and finite element model of steel tube.
Effect of Cathodic Protection Potential Fluctuations on the Corrosion of Low-Carbon Steels and Hydrogen Absorption by the Metal in Chloride Solutions with Nearly Neutral pH
Authors: Marshakov Andrey I. , Rybkina Alevtina A.
Published: November 2022

Considerable fluctuations in the cathodic protection potential under the impact of stray currents lead to the occurrence of local corrosion on steel structures operated in soils and seawater. The potential fluctuations induced by both alternating and direct current sources can be simulated by cycling a square potential step. This paper covers the impact of sign-alternating cyclic polarization (SACP) on the general and local corrosion of carbon steel in 3.5% NaCl solution containing a borate buffer (pH 6.7) and without it. A decrease in the cathodic half-period potential (Ec) of SACP inhibited the general corrosion and accelerates the local corrosion of steel in both solutions, which was associated with an increase in the amount of hydrogen in the metal. Increasing the duration of the SACP cathodic half-period increased the pit density and total area at less negative Ec values. At more negative Ec values, an increase in the duration of cathodic polarization reduced the intensity of steel local corrosion in the unbuffered chloride solution. This effect is explained by blocking of the pit nucleation centers on the metal surface by a layer of steel dissolution products formed in the near-electrode electrolyte layer with a high pH. The combined body of data shows that hydrogen absorption by the metal determines the corrosion behavior of carbon steel under the impact of SACP in chloride solutions, which should be taken into account in the development of models of the corrosion of steel structures under the action of stray currents.
Influence of Cellulose Nanofibers on the Behavior of Pickering Emulsions. Part 1. Microscopy and Startup Flow Test
Authors: Cui Shu-Ming , Hashmi Saud , Li Wen-Qiang , Handschuh-Wang Stephan , Zhu Cheng-Tian , Wang Shi-Chang , Yang Pian-Pian , Huang Yan-Fei , Zhu Guang-Ming , Stadler Florian J.
Published: November 2022

The dispersibility of flexible polymer chains present at the emulsion’s interface between the dispersed and continuous phase has obvious effects on rheology and dielectric properties of the whole emulsion. Cellulose nanofiber (CNF)-based Pickering emulsions are good systems to research these properties with respect to their microscopic phase structure, dielectric, and rheological properties by using CNF as a water-dispersible Pickering emulsifier, liquid paraffin as an oil phase, and didodecyldimethylammonium bromide (DDAB) as a cationic auxiliary surfactant. The CNF and DDAB contents were systematically varied while the water-to-paraffin oil ratio was kept constant to discern the influence of the Pickering emulsifiers. Polarized optical microscopic images reveal that the droplets tend to shrink at higher CNF content but grow bigger when increasing the DDAB content, which is proved by fluorescence analysis of the CNF dispersibility with varying DDAB content. The dielectric damping exhibits a minimum, whose value decreases with increasing DDAB and CNF content. Increasing the DDAB content promotes the solubilization of CNF in the aqueous phase, which will increase the overall viscosity and yield points. Similarly, a higher CNF content leads to a higher viscosity and yield point, but at high DDAB contents, the viscosity function exhibits an S-shape at intermediate CNF contents. To evaluate the results further, they were compared with CNF dispersions (without oil phase), which showed a surfactant effect slightly on maximum stress but strongly on yield stress τy, indicating that DDAB can promote the formation of a CNF network rather than the viscosity of the whole system. This paper provides information on how a systematical variation of the composition influences morphology and physico-chemical interactions as detected by broadband dielectric spectroscopy and rheological behavior.
Relation between Shear Stresses and Flexural Tensile Stresses from Standardized Tests of Extracted Prismatic Specimens of an SFRC Bridge Girder
Authors: Quiroga Flores Alfredo , Mendes de Andrade Rodolfo Giacomim , Pfeil Michèle Schubert , Barros Joaquim A. O. , Battista Ronaldo Carvalho , Oliveira de Araújo Olga Maria , Tadeu Lopes Ricardo , Toledo Filho Romildo Dias
Published: November 2022

Experimental research on the direct shear behavior of fiber-reinforced concrete is often carried out using prisms molded with specific dimensions for a standardized test. However, the flow of fresh concrete in these molds can be different than in the case of a full-scale structural element. This is important considering that the flow direction highly influences the distribution and orientation of fibers. In addition, most of the studies did not relate their shear results to other mechanical properties. In contrast, this study attempted to deepen the experimental knowledge of the crack propagation of a steel fiber-reinforced concrete (SFRC) used in a full-scale prototype of a bridge box girder built in the laboratory. Prismatic specimens were sawn from webs and top flanges of this prototype. Serving as references, additional specimens were molded in wooden boxes. In a previous study of our research group, both had been tested under a three-point notched bending configuration maintaining test conditions proportional to the EN14651 specifications. From each of the previously flexurally tested specimens, two prismatic specimens suitable for the Fédération Internationale de la Précontrainte (FIP) shear test setup were extracted by adopting a cutting methodology that avoided the damage induced by the flexural tests to be part of the FIP specimens. These FIP specimens were tested in almost pure shear loading conditions for assessing the performance of SFRC. Computer tomography images and photos of the shear failure faces were used to determine the distribution and density of fibers. The results demonstrated that the peak loads were proportional to the fiber density at the shear failure section. Assuming that the SFRC conditions of the webs were representative of a common batching procedure in the construction industry, the results from the tests in specimens extracted from these webs were adopted to establish shear stress/flexural tensile stress ratios vs. crack mouth opening displacement curves. The curves belonging to cross-sections of a similar fiber density in the shear and flexural cases allowed for the proposal of a normalized crack-dilatancy relation composed of three stages of the crack propagation. In addition, a trilinear crack width–slip relation was established using the same set of specimens. The relevancy of this proposal is that the shear response can be estimated from a widely accepted standardized flexural test, which demands a simpler instrumentation and is also easier to execute than the shear setup.
Infrared Stimulated Luminescence of Ce3+ Doped YAG Crystals
Authors: Bilski Paweł , Mrozik Anna , Gieszczyk Wojciech , Nizhankovskiy Sergiy , Zorenko Yuriy
Published: November 2022

In this study, the infrared optically stimulated luminescence (IRSL) of single crystals of Ce3+ doped yttrium aluminum garnet (YAG) was investigated for the first time. It was found that infrared stimulation of these crystals, following previous exposure to beta radiation, produces a strong luminescence signal. The highest luminescence efficiency was exhibited by the YAG crystal with 0.1% of Ce. With this crystal, it was possible to measure as low doses as 0.1 mGy. Moreover, IRSL is mainly related to the TL peak at a relatively high temperature of c.a. 175 °C, which leads to quite good stability of the signal in time. These properties create good prospects for potential applications of YAG:Ce in dosimetric radiation measurements
Investigations into Flux-Free Plasma Brazing of Aluminum in a Local XHV-Atmosphere
Authors: Klett Jan , Bongartz Benedict , Viebranz Vincent Fabian , Kramer David , Hao Chentong , Maier Hans Jürgen , Hassel Thomas
Published: November 2022

As a lightweight construction material, aluminum plays a key role in weight reduction and, thus, sustainability in the transport industry. The brazing of aluminum and its alloys is impeded by the natural passivating oxide layer, which interferes with the brazing process. The presented study investigates the possibility of using a thermal silane-doped argon plasma to reduce this oxide layer in situ and thus eliminating the need to use hazardous chemical fluxes to enable high-quality brazing. Using plasma spectroscopy and an oxygen partial pressure probe, it was shown that a silane-doped argon plasma could significantly reduce the oxygen concentration around the plasma in a thermal plasma brazing process. Oxygen concentrations below 10−16 vol.-% were achieved. Additionally, metallographic analyses showed that the thickness of an artificially produced Al2O3-Layer on top of AlMg1 samples could be substantially reduced by more than 50%. With the oxide layer removed and inhibition of re-oxidation, silane-doped plasma brazing has the potential to become an economically efficient new joining method.
Molarity Effects of Fe and NaOH on Synthesis and Characterisation of Magnetite (Fe3O4) Nanoparticles for Potential Application in Magnetic Hyperthermia Therapy
Authors: Ganapathe Lokesh Srinath , Kazmi Jamal , Mohamed Mohd Ambri , Berhanuddin Dilla Duryha
Published: November 2022

In this study, the effect of molarity on the structural, magnetic, and heat dissipation properties of magnetite nanoparticles (MNPs) was investigated to optimise the parameters for potential application in magnetic hyperthermia therapy (MHT). MHT works based on the principle of local temperature rise at the tumour site by magnetic iron oxide nanoparticles (MIONPs) with the application of an alternating magnetic field. MHT is a safe method for cancer treatment and has minimal or no side effects. Magnetite (Fe3O4) is the best material among MIONPs to be applied in local MHT due to its biocompatibility and high saturation magnetisation value. MNPs were prepared by co-precipitation at varying molarity. Structural characterisation was performed via X-ray powder diffraction (XRD) for crystalline structure analysis and field-emission scanning electron microscopy (FESEM) for morphology and particle size analysis. Measurement of the magnetic properties of the as-synthesised MNPs was carried out using a vibrating sample magnetometer (VSM). Power loss (P) was determined theoretically. The increase in molarity resulted in significant effects on the structural, magnetic, and heat dissipation properties of MNPs. The particle size and saturation magnetisation (Ms) decreased with the gradual addition of base but increased, together with crystallinity, with the gradual addition of iron source. M3 recorded the smallest crystalline size at 3.559 nm. The sample with the highest molarity (M4) displayed the highest heat generation capacity with a p value of up to 0.4056 W/g. High p values at the nano-scale are crucial, especially in local MHT, for effective heat generation, thus proving the importance of molarity as a vital parameter during MNP synthesis.
An Enhanced Northern Goshawk Optimization Algorithm and Its Application in Practical Optimization Problems
Authors: Liang Yan , Hu Xianzhi , Hu Gang , Dou Wanting
Published: November 2022

As a kind of effective tool in solving complex optimization problems, intelligent optimization algorithms are paid more attention to their advantages of being easy to implement and their wide applicability. This paper proposes an enhanced northern goshawk optimization algorithm to further improve the ability to solve challenging tasks. Firstly, by applying the polynomial interpolation strategy to the whole population, the quality of the solutions can be enhanced to keep a fast convergence to the better individual. Then, to avoid falling into lots of local optimums, especially late in the whole search, different kinds of opposite learning methods are used to help the algorithm to search the space more fully, including opposite learning, quasi-opposite learning, and quasi-reflected learning, to keep the diversity of the population, which is noted as a multi-strategy opposite learning method in this paper. Following the construction of the enhanced algorithm, its performance is analyzed by solving the CEC2017 test suite, and five practical optimization problems. Results show that the enhanced algorithm ranks first on 23 test functions, accounting for 79.31% among 29 functions, and keeps a faster convergence speed and a better stability on most functions, compared with the original northern goshawk optimization algorithm and other popular algorithms. For practical problems, the enhanced algorithm is still effective. When the complexity of the TSP is increased, the performance of the improved algorithm is much better than others on all measure indexes. Thus, the enhanced algorithm can keep the balance between exploitation and exploration and obtain better solutions with a faster speed for problems of high complexity.
Enumerating Discrete Resonant Rossby/Drift Wave Triads and Their Application in Information Security
Authors: Hayat Umar , Ullah Ikram , Murtaza Ghulam , Azam Naveed Ahmed , Bustamante Miguel D.
Published: November 2022

We propose a new parametrization of the resonant Rossby/drift wave triads to develop an algorithm to enumerate all resonant triads in a given grid of wavenumbers. To arrive at such a parametrization, we have employed tools from arithmetic/algebraic geometry to project resonant triads on a certain class of conics. Further, we extend the newly developed algorithm for the enumeration of quasi-resonant triads and experimentally show that the said algorithm is robust to design the network of quasi-resonances. From the experimental results, we observed that the new algorithm enumerates all triads in low computation time when compared with the existing methods. Finally, we apply this work to information security by constructing a total order on the enumerated resonant triads to design a substitution box (S-box) generator. Via extensive analyses over several indicators (nonlinearity, algebraic complexity, linear and differential approximation probabilities, strict avalanche criteria, and bit independence criterion) we show that the newly developed S-box outperforms the S-boxes constructed by most of the existing schemes.
Disease Spread among Hunted and Retaliating Herding Prey
Authors: Venturino Ezio
Published: November 2022

Two new ecoepidemic models of predator–prey type are introduced. They feature prey that gather in herds. The specific novelty consists of the fact that the prey also has the ability to defend themselves if they are in large numbers. The two deterministic models differ in the way a disease spreading among the ecosystem is transmitted, either by direct contact among infected and susceptible animals or by the intake of a virus present in the environment. Only the disease-free and the endemic equilibrium are allowed, and they are analyzed for feasibility and stability. The boundedness results allow us to gather some results regarding global stability. Persistent oscillations can be triggered when some relevant model parameters cross specific thresholds, causing repeated epidemic outbreaks. Furthermore, the environmental contamination through a free viruses destabilizes the endemic equilibrium and may lead to large amplitude oscillations, which are dangerous because they are potentially harmful to ecosystems. The bifurcation parameters leading to the limit cycle onset are related to the epidemics. For instance, they could be the disease-related mortality and the transmission rates, whether by direct contact among individuals or through the environment. The results of this investigation may provide insights to theoretical ecologists and may provide useful indications for epidemic spread containment.
MHD Mixed Convection of Hybrid Ferrofluid Flow over an Exponentially Stretching/Shrinking Surface with Heat Source/Sink and Velocity Slip
Authors: Zainodin Syafiq , Jamaludin Anuar , Nazar Roslinda , Pop Ioan
Published: November 2022

This paper investigates the mixed convection flow related to Fe3O4-CoFe2O4/water hybrid ferrofluids on stagnation point over an exponentially stretching/shrinking surface with the influence of magnetohydrodynamic (MHD), velocity slip, and heat source/sink. The proposed system of differential equations is reduced using the similarity transformation procedure that is numerically solvable using MATLAB. Dual solutions are obtained for various governing parameters, in which the first solution is found to be in a stable state via the stability analysis. The CoFe2O4 nanoparticles volume fraction increases the heat transfer rate and the skin friction coefficient while delaying the separation of the boundary layer at the bifurcation point. Adding CoFe2O4 nanoparticles in hybrid ferrofluids gives a better heat transfer rate than that obtained with ferrofluids. The presence of a magnetic field enhances the fluid flow velocity. The increased strengths of the heat sink and stretching parameters give better results on the heat transfer, while the results are reversed for the heat source and shrinking parameters. The presence of velocity slip does influence the skin friction and the fluid flow.
Adipose Autologous Micrograft and Its Derived Mesenchymal Stem Cells in a Bio Cross-Linked Hyaluronic Acid Scaffold for Correction Deep Wrinkles, Facial Depressions, Scars, Face Dermis and Its Regenerations: A Pilot Study and Cases Report
Authors: Svolacchia Lorenzo , Prisco Claudia , Giuzio Federica , Svolacchia Fabiano
Published: November 2022

The aim of this clinical study was to demonstrate that through a micrograft of viable adipose tissue cells microfiltered at 50 microns to exclude fibrous shoots and cell debris in a suspension of cross-linked hyaluronic acid, we were able to improve visible imperfections of the dermis and to improve clinically observable wrinkles, with a beneficial effect also in the extracellular matrix (ECM). Background and Objectives: With the passage of time, the aging process begins, resulting in a progressive impairment of tissue homeostasis. The main reason for the formation of wrinkles is the involution of the papillary dermis, as well as the loss of stem cell niches with compromise of the extra-cytoplasmic matrix (ECM), and the loss of hyaluronic acid, which helps to maintain the shape and resistance and that is contained in the connective tissue. Materials and Methods: This study involved 14 female patients who underwent dermal wrinkle correction and bio-regeneration over the entire facial area through a suspension containing 1.0 mL of viable micrografts from adipose tissue in a 1.0 mL cross-linked hyaluronic acid. To verify the improvement of the anatomical area concerned over time, the various degrees of correction obtained for wrinkles, and in general for texture, were objectively evaluated by using a Numeric Rating scale (NRS) 10–0, a modified Vancouver scale and a Berardesca scale. Results: The Berardesca, NRS and Modified Vancouver scales showed that with this technique it was possible to obtain excellent results both when the suspension was injected into wrinkles with the linear retrograde technique, and when it was injected with the micropomphs technique to correct furrows, with the intent to revitalize the tissue through progenitors with adult stemness markers. Conclusions: The combination of microfragmented and microfiltered adipose tissue and cross-linked hyaluronic acid at 50 microns is safe new method to treat soft tissue defects such as deep wrinkles.