bluuebunny/crossref_metadata_2025 huggingface dataset:
Classification of Aviation Alloys Using Laser-Induced Breakdown Spectroscopy Based on a WT-PSO-LSSVM Model
Authors: Guo Haorong , Cui Minchao , Feng Zhongqi , Zhang Dacheng , Zhang Dinghua
Published: June 2022

It is well-known that aviation alloys of different grades show large differences in mechanical properties. At present, alloys must be strictly distinguished in the manufacturing plant because their close appearance and density are easily confused In this work, the wavelet transform (WT) method combined with the least squares support vector machine (LSSVM) is applied to the classification and identification of aviation alloys by laser-induced breakdown spectroscopy (LIBS). This experiment employed six different grades of aviation alloy as the classification samples and obtained 100 sets of spectral data for each sample. This research included the steps of preprocessing the obtained spectral data, model training, and parameter optimization. Finally, the accuracy of the training set was 99.98%, and the accuracy of the test set was 99.56%. Therefore, it is concluded that the model has superior generalization capacity and portability. The result of this work illustrates that LIBS technology can be adopted for the rapid identification of aviation alloys, which is of great significance for on-site quality control and efficiency improvement of aerospace parts manufacturing.
Children’s Drawing of Plant Life in the Time of COVID-19: An Analysis of the Changes Related to Content and Colour over a Two-Year Period
Authors: Zaballa Ilargi , Merino Maria , Villarroel José Domingo
Published: June 2022

This study analyses the depictions that a sample of young children completed to express their knowledge of plant life at two different times, two years apart. The pictorial content is examined by the complexity of the depictions of flora as well as the range of colour that the children in the sample chose. The study presents the changes that occurred in the children’s illustrations of plants after 24 months. The conclusions are discussed in view of the data that preceding studies provide on the subject of botanical literacy in childhood, and raise the hypothesis that the unexpected results obtained in the study might reflect a learning loss in the understanding of the plant world as a consequence of the school closures that followed the outbreak of the COVID-19 pandemic.
Diagnostic Values of Red Flags and a Clinical Prediction Score for Emergent Intracranial Lesions in Non-Traumatic Pediatric Headaches
Authors: Manoyana Atipat , Angkurawaranon Salita , Katib Sumintra , Wiwattanadittakul Natrujee , Sirikul Wachiranun , Angkurawaranon Chaisiri
Published: June 2022

Introduction: Diagnosis of emergent intracranial lesions that require emergency treatment either medically or surgically in non-traumatic pediatric headaches is important. Red-flag signs and symptoms are commonly used as justification for neuroimaging; however, evidence on its diagnostic values is limited. The study aims to identify diagnostic values of red-flags and develop a clinical prediction score to help improve the diagnostic yield of neuroimaging. Methods: A retrospective review of 109 pediatric patients from 2006 to 2020 who presented with a non-traumatic headache was conducted. A clinical prediction score from red flags was developed using multivariate logistic regression. Discriminatory ability was examined using the area under the receiver operating characteristic curve. Results: A total of 51 patients were diagnosed with emergent intracranial lesions. Four potential clinical red flag predictors were identified: (1) acute onset (less than 3 months), (2) altered conscious state, (3) focal motor abnormality, and (4) and ocular/pupillary abnormality or squint. A clinical prediction score was developed with good discriminatory properties (0.84). Conclusions: Clinical predictor scores from these four red flags may play an important role in maximizing neuroimaging and proper management for pediatric patients with non-traumatic headaches. Future validation studies are needed and could guide referrals and optimize the use of neuroimaging for these patients.
Further Validation of the Crohn’s and Ulcerative Colitis Questionnaire-32 (CUCQ-32) to Measure the Quality of Life in Patients Treated with Biologics Therapy
Authors: Alrubaiy Laith , Sikafi Rafid , Hutchings Hayley Anne , Arnott Ian , Williams John Gordon
Published: June 2022

Background: Crohn’s and Ulcerative Colitis Questionnaire-32 (CUCQ-32) is a validated questionnaire to measure the quality of life (QoL) in Inflammatory Bowel Disease (IBD). However, it does not have stoma-specific questions and can be lengthy. This study aimed to validate a subset of the CUCQ-32 that would be suitable for patients with a stoma. Methods: Baseline data were collected from a cohort of patients with acute ulcerative colitis who were participating in the CONSTRUCT multicentre clinical trial. A subset of the CUCQ-32 questions was selected by stepwise regression. Further validation was examined using data from the UK IBD biological therapies audit. Construct validity was carried out using the EuroQol 5 dimensions (EQ5D) questionnaire, Simple Clinical Colitis Activity Index (SCCAI), and the Harvey–Bradshaw Index (HBI). Results: Using the data from 124 patients, a short-version questionnaire (CUCQ-12) was developed. Data from 484 patients with IBD (382 patients with Crohn’s disease, 76 patients with ulcerative colitis, and 26 patients with IBD-Unclassified) and 61 patients with stoma provided further validation of the CUCQ-12. A literature review and an expert focus group identified supplementary stoma-specific questions for the CUCQ-12+. The CUCQ-12+ demonstrated excellent internal consistency (Cronbach’s α = 0.86); established effective reproducibility (intra-class correlation coefficient = 0.74); correlated well with the EQ5D (r= −0.48), HBI (r = 0.45), and SCCAI (r = 0.43); and represented good responsiveness statistics (>0.5). Conclusions: CUCQ-12+ is a valid and reliable QoL measure used for all patients with IBD in clinical practice, including patients with a stoma.
Effect of Humidity on Metallizing on Polyphenylene Sulfide (PPS) with Atmospheric UV Treatment
Authors: Yamagishi Toshimichi , Inoue Tomoaki , Watanabe Mitsuhiro
Published: June 2022

Polyphenylene sulfide (PPS) is an engineering plastic; when reinforced with fillers, it exhibits high heat resistance, strength, and molding/dimensional stability. Plating on PPS without using harmful chemicals can meet the following requirements due to its excellent properties: low environmental load process, lightweight metal substitute materials, electromagnetic wave shielding materials, etc. This study focused on metallizing by atmospheric ultraviolet (UV) treatment of PPS. This process is generally used for the pretreatment of painting and adhesion, and it entails a small environmental load; however, the UV treatment of moist air produces various chemical species. Therefore, the humidity effect during metallizing via atmospheric UV treatment was investigated, revealing its influence on the adhesion strength of the resulting metal film. In a dry environment, a metal film with strong adhesion can be formed on PPS, and UV treatment under such conditions can maintain the structure of the PPS surface. In contrast, a weak layer was generated under wet conditions, reducing the adhesion strength between the metal film and PPS.
Seawater Corrosion of Copper and Its Alloy Coated with Hydrothermal Carbon
Authors: Gan Yong , Chang Yizhe , Chen Chuan-Chiang , Li Mingheng , Gan Jeremy , Li Joseph
Published: June 2022

Nonferrous materials such as copper and its alloys are sensitive to seawater corrosion. In this work, a hydrothermal carbonization coating was deposited on a C26000 brass and pure copper. The effectiveness of the coating on improving seawater corrosion performance was examined. First, hydrothermal carbonization of sugar (with 10 wt.% sucrose in water) at 200 °C and 1.35 MPa for 4 h was performed to generate the carbon-rich coating. The results of surface morphology, composition, hardness, thickness, and wettability to seawater were presented. Then, the corrosion resistance of the brass and pure copper with and without coating was evaluated by measuring the Tafel constants in seawater. Important parameters including the corrosion current, potentials of corrosion, and polarization resistance for the brass and pure copper with and without the coating were calculated from the polarization measurement data. It was found that the hydrothermal carbonization of sugar produced a relatively dense carbon-rich layer on the surface of the copper and brass specimens. This carbon layer has a thickness of 120 µm, and it is highly corrosion resistant. The corrosion current of the copper and its alloy in seawater is reduced significantly through the hydrothermal carbonization treatment. The carbonized coating reduced the corrosion current obviously, but only resulted in a small positive shift of 0.05–0.1 V in the corrosion potentials. The hydrothermally produced carbon layer is just like a passivation coating on the pure copper and copper alloy to slow down their corrosion rates in seawater.
Robust Super-Amphiphobic Titanium Surface for Liquid/Liquid Mini Separations
Authors: Zhang Yuping , Wang Ning , Cui Chengxing , Chen Jun , Chen Na , Zhang Yijun
Published: June 2022

Super-amphiphobic surface with low robustness is not suitable for practical application due to its weak mechanical strength. In this work, an in-site growth of micro-/nanoscale flower-like TiO2 on the surface of a titanium mesh was successfully fabricated through hydrothermal synthesis, followed by chemical modification with low-surface-energy heptadecafluoro-1,1,2,2-tetrahydrodecyl trichlorosilane. The resultant super-amphiphobic coating was highly repellent to all of the ethanol–water mixtures with surface tensions ranging over 26.0–72.8 mN/m, as well as excellent chemical and mechanical durability. After it was irradiated for 8 h with ultraviolet light, it was used for oil/water and oil/oil mini-separation with the help of its Janus characteristic. This was attributed to its unidirectional penetration for liquid droplets with different surface tension values. This kind of smart super-amphiphobic mesh with photochemical activity could potentially gate and sort liquids via surface tensions.
Bubble-Patterned Films by Inkjet Printing and Gas Foaming
Authors: Loffredo Fausta , Villani Fulvia , Choy Buentello David , Trujillo-de Santiago Grissel , Alvarez Mario Moisés , Miscioscia Riccardo , Di Maio Ernesto
Published: June 2022

The micropatterning of thin films represents a challenging task, even for additive manufacturing techniques. In this work, we introduce the use of inkjet-printing technology coupled with a gas-foaming process, to produce patterned porosities on polymeric thin films, to develop a bubble-writing method. Inkjet printing of an aqueous solution of poly (vinyl alcohol) (PVA), a well-known gas-barrier polymer, allows the selective coating of a thin poly (lactic acid) (PLA) film, which is, successively, exposed to a gas-foaming process. The foaming of the thin PLA film is effective, only when PVA is printed on top, since the PVA barrier hinders the premature loss of the gas, thus allowing the formation of cavities (bubbles) in the covered areas; then, removing the PVA coating by water washing forms a bubble pattern. As a proof of concept, the surface-morphology features of the patterned porous PLA films have been proven effective at driving endothelial cell growth. A new technological platform is, hence, introduced in the field of tissue engineering and, in general, in fields involving thin films, where a patterned porous structure may add value.
Diffusion Barrier Characteristics of WSiN Films
Authors: Chen Yung-I , Yeh Kuo-Hong , Ou Tzu-Yu , Chang Li-Chun
Published: June 2022

WSiN films were produced through hybrid pulse direct current/radio frequency magnetron co-sputtering and evaluated as diffusion barriers for Cu metallization. The Cu/WSiN/Si assemblies were annealed for 1 h in a vacuum at 500–900 °C. The structural stability and diffusion barrier performance of the WSiN films were explored through X-ray diffraction, Auger electron spectroscopy, and sheet resistance measurement. The results indicated that the Si content of WSiN films increased from 0 to 9 at.% as the power applied to the Si target was increased from 0 to 150 W. The as-deposited W76N24, W68Si0N32, and W63Si4N33 films formed a face-centered cubic W2N phase, whereas the as-deposited W59Si9N32 film was near-amorphous. The lattice constants of crystalline WSiN films decreased after annealing. The sheet resistance of crystalline WSiN films exhibited a sharp increase as they were annealed at 800 °C, accompanied by the formation of a Cu3Si compound. The failure of the near-amorphous W59Si9N32 barrier against Cu diffusion was observed when annealed at 900 °C.
Comparison of Microstructure, Microhardness, Fracture Toughness, and Abrasive Wear of WC-17Co Coatings Formed in Various Spraying Ways
Authors: Chen Xiao , Li Chengdi , Gao Qinqin , Duan Xixi , Liu Hao
Published: June 2022

WC-Co cermet materials serving as protective coatings are widely used in many fields. Conventional WC-17Co coatings were formed in high-velocity oxygen-fuel (HVOF), warm spraying (WS), and cold spraying (CS), respectively. Deposition behavior of a single WC-17Co particle, as well as the microstructure, microhardness, fracture toughness, and abrasive wear of WC-17Co coatings formed in various spraying ways were investigated. The results show that the deposition behavior of a single WC-17Co particle was different after it was deposited onto a Q235 steel substrate in various spraying ways. The WC-17Co splat deposited by HVOF showed a center hump and some molten areas, as well as some radial splashes presented at the edge of the splat. The WC-17Co splat deposited by WS presented a flattened morphology with no molten areas. However, the WC-17Co splat deposited by CS remained nearly spherical in shape and embedded into the substrate to a certain depth. All the WC-17Co coatings had the same phase compositions with that of feedstock. The microstructure of all the WC-17Co coatings was dense with no cracks or abscission phenomena between the coatings and substrate. Moreover, fine WC particles were formed in the coatings due to the fracture of coarse WC particles, and the content of fine WC particles in the cold-sprayed coating was significantly more than the other coatings. A stripe structure was formed by the slippage of fine WC particles with a plastic flow of Co binder in the warm-sprayed and cold-sprayed coatings. More fine WC particles, as well as the stripe structure, in the coatings were conducive to improve the microhardness and fracture toughness of the coating. The microhardness and fracture toughness of the cold-sprayed WC-17Co coating were the highest among the coatings. The main wear mechanism of all coatings was the groove and some peel-offs. The cold-sprayed WC-17Co coating with the lowest wear loss presented the highest wear resistance among the coatings.
The Effects of Nozzle Inclination, Area Ratio, and Side-Hole Aspect Ratio on the Flow Behavior in Mold
Authors: Du Fengming , Li Tianyi , Zheng Gengtao
Published: June 2022

During the steel continuous casting, the submerged entry nozzle (SEN) plays a crucial role in the fluid characteristic of fluid steel, which further affects the slab quality. In this paper, a nozzle model is developed to study the influences of nozzle inclination, nozzle area ratio, and side hole aspect ratio on the fluid characteristic of fluid steel. The results show that when the nozzle angle increased from 10° to 20°, the impact points of the narrow surface were 0.402 m, 0.476 m, and 0.554 m away from the meniscus, respectively. In addition, when the nozzle area ratio increased from 0.96 to 1.16, it resulted in a significant decrease of the speed of high-temperature liquid steel flowing out of the nozzle. Moreover, when the side-hole aspect ratio was 1.47, the maximum turbulent kinetic energy of the free surface reached 0.00141 m2 s−2. Furthermore, when the aspect ratio was 1.67 and 1.84, a slight difference existed, and the maximum turbulent kinetic energy was almost 0.00095 m2 s−2. The proposed model can provide theoretical basis and guidance for nozzle optimization.
Comparison of Novel Low-Carbon Martensitic Steel to Maraging Steel in Low-Cycle Fatigue Behavior
Authors: Lv Bo , Xia Shule , Zhang Fucheng , Yang Guang , Long Xiaoyan
Published: June 2022

The study systematically compares the low-cycle fatigue (LCF) behaviors of novel martensitic steel (22MnSi2CrMoNi) and maraging steel (00Ni18Co9Mo4Ti). Results show that the two types of tested steel have a similar cyclic deformation behavior. The cyclic softening resistance of 22MnSi2CrMoNi steel is slightly inferior to that of 00Ni18Co9Mo4Ti steel at a low total strain amplitude. However, the gap gradually disappears with the increase of the total strain amplitude. At the same plastic strain amplitude, the LCF lifetime of 22MnSi2CrMoNi steel is higher than that of 00Ni18Co9Mo4Ti steel. The retained austenite film between martensite lath and the existence of precipitated phase in matrix can effectively improve the fatigue lifetime of the two types of tested steel.
Investigation of the Nature of the Interaction of Me-MeN-(Me,Mo,Al)N Coatings (Where Me = Zr, Ti, or Cr) with a Contact Medium Based on the Ni-Cr System
Authors: Grigoriev Sergey , Yanushevich Oleg , Krikheli Natella , Vereschaka Alexey , Milovich Filipp , Andreev Nikolay , Seleznev Anton , Shein Alexander , Kramar Olga , Kramar Sergey , Peretyagin Pavel
Published: June 2022

This paper discusses the results of a study focused on the nature of the interaction of Me-MeN-(Me,Mo,Al)N coatings (where Me = zirconium (Zr), titanium (Ti), or chromium (Cr)) with a contact medium based on the Ni-Cr system. The studies were carried out during the turning of nickel–chromium alloy at different cutting speeds. The hardness of the coatings was found, and their nanostructure and phase composition were studied. The experiments were conducted using transmission electron microscopy (TEM), X-ray diffraction (XRD), and selected area electron diffraction (SAED). According to the studies, at elevated cutting speeds, the highest wear resistance is demonstrated by the tools with the ZrN-based coating, while at lower cutting speeds, the tools with the TiN- and CrN-based coatings had higher wear resistance. At elevated cutting speeds, the experiments detected the active formation of oxides in the ZrN-based coating and less active formation of oxides in the CrN-based coating. No formation of oxides was detected in the TiN-based coating. The patterns of cracking in the coatings were also studied.
Improved Unsupervised Learning Method for Material-Properties Identification Based on Mode Separation of Ultrasonic Guided Waves
Authors: Golub Mikhail V. , Doroshenko Olga V. , Arsenov Mikhail A. , Eremin Artem A. , Gu Yan , Bareiko Ilya A.
Published: June 2022

Numerical methods, including machine-learning methods, are now actively used in applications related to elastic guided wave propagation phenomena. The method proposed in this study for material-properties characterization is based on an algorithm of the clustering of multivariate data series obtained as a result of the application of the matrix pencil method to the experimental data. In the developed technique, multi-objective optimization is employed to improve the accuracy of the identification of particular parameters. At the first stage, the computationally efficient method based on the calculation of the Fourier transform of Green’s matrix is employed iteratively and the obtained solution is used for filter construction with decreasing bandwidths providing nearly noise-free classified data (with mode separation). The filter provides data separation between all guided waves in a natural way, which is needed at the second stage, where a more laborious method based on the minimization of the slowness residuals is applied to the data. The method might be further employed for material properties identification in plates with thin coatings/interlayers, multi-layered anisotropic laminates, etc.
Artificial Intelligence for Sustainable Complex Socio-Technical-Economic Ecosystems
Authors: Martínez-García Alejandro N.
Published: June 2022

The strong and functional couplings among ecological, economic, social, and technological processes explain the complexification of human-made systems, and phenomena such as globalization, climate change, the increased urbanization and inequality of human societies, the power of information, and the COVID-19 syndemic. Among complexification’s features are non-decomposability, asynchronous behavior, components with many degrees of freedom, increased likelihood of catastrophic events, irreversibility, nonlinear phase spaces with immense combinatorial sizes, and the impossibility of long-term, detailed prediction. Sustainability for complex systems implies enough efficiency to explore and exploit their dynamic phase spaces and enough flexibility to coevolve with their environments. This, in turn, means solving intractable nonlinear semi-structured dynamic multi-objective optimization problems, with conflicting, incommensurable, non-cooperative objectives and purposes, under dynamic uncertainty, restricted access to materials, energy, and information, and a given time horizon. Given the high-stakes; the need for effective, efficient, diverse solutions; their local and global, and present and future effects; and their unforeseen short-, medium-, and long-term impacts; achieving sustainable complex systems implies the need for Sustainability-designed Universal Intelligent Agents (SUIAs). The proposed philosophical and technological SUIAs will be heuristic devices for harnessing the strong functional coupling between human, artificial, and nonhuman biological intelligence in a non-zero-sum game to achieve sustainability.
Assessment of Virtual Reality among University Professors: Influence of the Digital Generation
Authors: Antón-Sancho Álvaro , Fernández-Arias Pablo , Vergara Diego
Published: June 2022

This paper conducts quantitative research on the assessment made by a group of 623 Spanish and Latin American university professors about the use of virtual reality technologies in the classroom and their own digital skills in this respect. The main objective is to analyze the differences that exist in this regard due to the digital generation of the professors (immigrants or digital natives). As an instrument, a survey designed for this purpose was used, the validity of which has been tested in the study. It was found that digital natives say they are more competent in the use of virtual reality and value its technical and didactic aspects more highly, although they also identify more disadvantages in its use than digital immigrants. Differences in responses were found by gender and areas of knowledge of the professors with respect to the opinions expressed. It is suggested that universities design training plans on teaching digital competence and include in them the didactic use of virtual reality technologies in higher education.
Automated Detection of Left Bundle Branch Block from ECG Signal Utilizing the Maximal Overlap Discrete Wavelet Transform with ANFIS
Authors: Al-Naami Bassam , Fraihat Hossam , Owida Hamza Abu , Al-Hamad Khalid , De Fazio Roberto , Visconti Paolo
Published: June 2022

Left bundle branch block (LBBB) is a common disorder in the heart’s electrical conduction system that leads to the ventricles’ uncoordinated contraction. The complete LBBB is usually associated with underlying heart failure and other cardiac diseases. Therefore, early automated detection is vital. This work aimed to detect the LBBB through the QRS electrocardiogram (ECG) complex segments taken from the MIT-BIH arrhythmia database. The used data contain 2655 LBBB (abnormal) and 1470 normal signals (i.e., 4125 total signals). The proposed method was employed in the following steps: (i) QRS segmentation and filtration, (ii) application of the Maximal Overlapped Discrete Wavelet Transform (MODWT) on the ECG R wave, (iii) selection of the detailed coefficients of the MODWT (D2, D3, D4), kurtosis, and skewness as extracted features to be fed into the Adaptive Neuro-Fuzzy Inference System (ANFIS) classifier. The obtained results proved that the proposed method performed well based on the achieved sensitivity, specificity, and classification accuracies of 99.81%, 100%, and 99.88%, respectively (F-Score is equal to 0.9990). Our results showed that the proposed method was robust and effective and could be used in real clinical situations.
The Role of Preservatives and Multifunctionals on the Oxidation of Cosmetic O/W Emulsions
Authors: Springer Arielle , Ziegler Helena
Published: June 2022

Preservatives are typically used to protect cosmetic products from microbial spoilage. However, there is evidence that some preservatives can increase oxidation in O/W emulsions. This could have disadvantages for product quality, efficacy, and consumer health and well-being. Therefore, the impact of preservatives or multifunctionals on oxidation should be quantified. For this purpose, five O/W emulsions with different preservatives were prepared and stored. During storage, the oxygen concentration in the headspace of the samples was studied. The samples showed significant differences in their oxygen uptake and daily oxygen consumption rate. Thus, the preservatives used in this study had an influence on oxidation.
Effects of Structure on the Solubility of UV Filters
Authors: Del Olmo Marc , Navarro Àngel , Garcia Cristina , Ehara Taro , Beltran Lluís
Published: June 2022

In recent years, one of the most concerning topics in healthcare is the constant exposure to ultraviolet (UV) light being the cause of numerous skin diseases. This issue created a keen interest in sun-care cosmetics, and particularly in sunscreens, since it has been proven to significantly reduce human skin disorders. Usually, sunscreens are formulated as emulsions with organic UV-absorbers dissolved in the oil phase; thus, the solubility of these UV-filters in the emollients is crucial. In this work we expose the properties of different emollients, correlating the chemical structure with the ability to dissolve organic UV-filters.
Numerical Simulation of Residual Stress and Deformation in Wire Arc Additive Manufacturing
Authors: Feng Guangjie , Wang Hu , Wang Yifeng , Deng Dean , Zhang Jian
Published: June 2022

In this paper, multi-layer and multi-pass arc additive manufacturing experiments were carried out on the Q345 substrate using Y309L welding wire. Based on MSC. Marc software, a thermal-elastic-plastic finite element method was developed to numerically simulate the temperature field, stress field, and deformation during the additive manufacturing process. The effects of the substrate thickness and interpass temperature on the temperature field, stress field, and deformation were discussed. The results indicated that the deposition materials at different positions experienced different thermal cycles, which might lead to the non-uniform microstructure and mechanical properties within the workpiece. The interpass temperature and the thickness of the substrate influenced the residual stress distribution in the additive manufactured structure. A low interpass temperature and thin substrate was able to effectively reduce the tensile residual stress. The thick substrate resulted in a small angular deformation of the substrate during the additive manufacturing process.
Low-Vacuum Pyrolysis of YBCO Films by Using Fluorine-Free Metal Organic Chemical Deposition
Authors: Yang Zhao , Cai Chuanbing , Chu Ningdong , Tong Shuyun , Lu Yuming , Liu Zhiyong
Published: June 2022

The preparation of YBCO superconducting films by using metal organic chemical deposition (MOD) involves low-temperature pyrolysis and high-temperature treatment. The former process generally requires the introduction of water vapor and other gases. The study on pyrolysis in a low vacuum environment and non-carrier gas atmosphere has never been reported. In this work, we explored a low vacuum pyrolysis scheme with simple Argon gas decompression and a carrier-free atmosphere. The effects of heating rate on the microstructure of pyrolysis films were investigated, and the high-temperature treatment temperature (Th) was also optimized. Compared with conventional pyrolysis, the present low-vacuum pyrolysis does not employ the flowing dry or wet gases, facilitating the internal gas release during film decomposition. More importantly, the efficiency was greatly improved with reduced pyrolysis time. The obtained film surface is free of CuO particle, which leads to a lower roughness. We also investigated the effect of Th on the final YBCO film texture and superconductivity. As Th increased from 810 °C to 815 °C, the BaCuO2 phase decreased with enhanced c-axis orientation being evident by XRD and Raman spectra. As a result, the critical current density (Jc) increased from 0.38 MA/cm2 to 1.2 MA/cm2 (77 K, self-field).
Silver Nanoparticles Synthesized Using Eichhornia crassipes Extract from Yuriria Lagoon, and the Perspective for Application as Antimicrobial Agent
Authors: Martínez-Espinosa Juan Carlos , Ramírez-Morales María Antonieta , Carrera-Cerritos Raúl
Published: June 2022

The antimicrobial effects of silver (Ag) ions and salts are well known. However, the antimicrobial effects, mechanism, and the cytotoxic activity in vitro of Ag nanoparticles (AgNP) has recently been validated. In this work, we report the green synthesis of AgNPs using the extract of Eichhornia crassipes as a reducing agent and evaluate its antimicrobial activity against Escherichia coli (ATCC-25922). The morphology, size, chemical composition, and inhibition properties of the nanoparticles as a function of the reduction time and temperature were analyzed. According to TEM imaging, nanoparticles with average diameters between 20–40 nm were synthesized. Antibacterial results suggest that AgNPs can be used as an effective growth inhibitor with higher antimicrobial activity against Escherichia coli after 120 min of reaction with a synthesis temperature of 95°. More extensive analysis is required for the appropriate selection of the synthesis parameters and adequate concentration for use in biomedical applications and antibacterial control systems.
Synergistic Antifungal Efficiency of Biogenic Silver Nanoparticles with Itraconazole against Multidrug-Resistant Candidal Strains
Authors: Yassin Mohamed Taha , Mostafa Ashraf Abdel-Fattah , Al-Askar Abdulaziz Abdulrahman , Al-Otibi Fatimah O.
Published: June 2022

Fungal infections caused by multidrug-resistant strains are considered one of the leading causes of morbidity and mortality worldwide. Moreover, antifungal medications used in conventional antifungal treatment revealed poor therapeutic effectiveness and possible side effects such as hepatotoxicity, nephrotoxicity, and myelotoxicity. Therefore, the current study was developed to determine the antifungal effectiveness of green synthesized silver nanoparticles (AgNPs) and their synergistic efficiency with antifungal drugs against multidrug-resistant candidal strains. The AgNPs were greenly synthesized using the aqueous peel extract of Punica granatum. In addition, AgNPs were characterized using ultraviolet-visible spectrophotometry (UV/Vis), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), and zeta potential analysis. In this regard, UV-vis analysis indicated SPR of AgNPs at 396 nm, while the particle size distribution revealed that the average particle size was 18.567 ± 1.46 nm. The surface charge of AgNPs was found to be −15.6 mV, indicating their stability in aqueous solutions. The biofabricated AgNPs indicated antifungal activity against Candida tropicalis, C. albicans, and C. glabrata strains showing inhibitory zone diameters of 23.78 ± 0.63, 21.38 ± 0.58, and 16.53 ± 0.21 mm, respectively while their minimum inhibitory concentration (MIC) was found to be 2.5 µg/mL against C. tropicalis strain. AgNPs and itraconazole revealed the highest synergistic activity against the multidrug-resistant strain, C. glabrata, recording a synergism percentage of 74.32%. In conclusion, the biogenic AgNPs in combination with itraconazole drug exhibited potential synergistic activity against different candidal strains indicating their potential usage in the bioformulation of highly effective antifungal agents.
Improvement of the Geometric Accuracy for Microstructures by Projection Stereolithography Additive Manufacturing
Authors: Wen Cheng , Chen Zhengda , Chen Zhuoxi , Zhang Bin , Cheng Zhicheng , Yi Hao , Jiang Guiyun , Huang Jigang
Published: June 2022

Projection stereolithography creates 3D structures by projecting patterns onto the surface of a photosensitive material layer by layer. Benefiting from high efficiency and resolution, projection stereolithography 3D printing has been widely used to fabricate microstructures. To improve the geometric accuracy of projection stereolithography 3D printing for microstructures, a compensation method based on structure optimization is proposed according to mathematical analysis and simulation tests. The performance of the proposed compensation method is verified both by the simulation and the 3D printing experiments. The results indicate that the proposed compensation method is able to significantly improve the shape accuracy and reduce the error of the feature size. The proposed compensation method is also proved to improve the dimension accuracy by 21.7%, 16.5% and 19.6% for the circular, square and triangular bosses respectively. While the improvements on the dimension accuracy by 16%, 17.6% and 13.8% for the circular, square and triangular holes are achieved with the proposed compensation method. This work is expected to provide a method to improve the geometric accuracy for 3D printing microstructures by projection stereolithography.
Synthesis of NiCo2S4@NiMoO4 Nanosheets with Excellent Electrochemical Performance for Supercapacitor
Authors: Wang Jian , Li Yucai , Zhao Yan , Zhang Dong , Song Shiwei , Ke Junjie
Published: June 2022

Currently, the research of energy storage devices mainly focuses on enhancing their electrochemical performance. Core-shell structured NiCo2S4@NiMoO4 is thought to be one of the most promising electrode materials for supercapacitors due to its high specific capacitance and excellent cycle performance. In this work, we report NiCo2S4@NiMoO4 nanosheets on Ni foam by a two-step fabricated method. The as-obtained product has a high capacitance of 1035 F g−1 at 1 A g−1. The as-assembled supercapacitor has a high energy density of 32.4 W h kg−1 at a power density of 3230 W kg−1 and a superior cycle performance, with 70.1% capacitance retention. The electrode materials reported here might exhibit potential applications in future energy storage devices.
Enhanced Electrodes for Supercapacitor Applications Prepared by Hydrothermal-Assisted Nano Sheet-Shaped MgCo2O4@ZnS
Authors: Alam Mir Waqas , Al Qahtani Hassan S. , Albalawi Hind , Aamir Muhammad , Bilal Muhammad , Ahmad Mir Tanveer , Souayeh Basma , Zaidi Noushi
Published: June 2022

In this paper, we report on nanodisc-shaped MgCo2O4 wrapped with ZnS, achieved using the sol–gel-assisted hydrothermal method. This enhances the electrochemical performance, with the electrode delivering superior supercapacitive performance compared to MgCo2O4. Moreover, the nanodisc provides more active sites and allows smooth charge transfer during faradaic reactions. The nanodisc-shaped MgCo2O4 with ZnS delivers a capacitance of approximately 910 F/g at 1 A/g. The fabricated asymmetric capacitor is composed of MgCo2O4@ZnS and activated carbon (AC). The nanodisc-shaped MgCo2O4@ZnS provides more active sites and allows the smooth transport of electrons during long-term cycling. In addition, the electrode side reactions and electrolyte decomposition are significantly reduced due to the ZnS coating on the surface of the MgCo2O4, allowing this asymmetric capacitor to deliver an energy density of 43 Wh·kg−1 at 1454 W·kg−1. The performance of the asymmetric capacitor exhibits enhanced supercapacitive performance and opens a new way to investigate asymmetric supercapacitor devices.
Revision of the Crystal Structure of the Orthorhombic Polymorph of Oxyma: On the Importance of π–Hole Interactions and Their Interplay with H–Bonds
Authors: Barbas Rafael , de Sande Dafne , Font-Bardia Mercè , Prohens Rafel , Frontera Antonio
Published: June 2022

In this work the crystal structure of the previously described orthorhombic polymorph of the coupling reagent Oxyma has been revised, corrected now as centrosymmetric and analyzed by means of DFT calculations. In the solid state the structure forms a network of H-bonds and self–assembled dimers that are held together by the formation of N···C π–hole interactions involving the C-atom of the imino group. The H-bonding and π–hole interactions observed in the solid state were rationalized using molecular electrostatic potential (MEP) surfaces, focusing on the H-bond donor-acceptor groups and the π-hole observed above and below the molecular plane. The interactions and their interplay have been characterized by using two methodologies based on the topology of the electron density, which are the quantum theory of “atom-in-molecules” (QTAIM) and the noncovalent interaction plot (NCIplot).
Not All That Glitters Is Gold: Barcoding Effort Reveals Taxonomic Incongruences in Iconic Ross Sea Sea Stars
Authors: Guzzi Alice , Alvaro Maria Chiara , Danis Bruno , Moreau Camille , Schiaparelli Stefano
Published: June 2022

The Southern Ocean is one of the most exposed regions to climate-related changes on our planet. Better understanding of the current biodiversity and past speciation events, as well as implementation of conservation actions and accurate identification of organisms to species level in this unique environment, is fundamental. In this study, two species of sea stars, Odontaster roseus Janosik & Halanych, 2010 and Odontaster pearsei Janosik & Halanych, 2010, are reported for the first time from the Terra Nova Bay area (TNB, Ross Sea, Antarctica) by using a combination of molecular (DNA barcoding) and morphological (coloration and skeletal features) analyses. Molecular results agree with external morphological characters of the two identified species, making occurrence in the area unequivocal. The two species were recently described from the Antarctic Peninsula, and went unnoticed for a long time in TNB, possibly having been confused with O. meridionalis (E.A. Smith, 1876), with which they share a bright yellow coloration. This latter species seems to be absent in the Ross Sea. Thus, the past literature referring to O. meridionalis in the Ross Sea should be treated with caution as these “yellow morphs” could be one of the two recently described species or even orange–yellow morphs of the red-colored congeneric O. validus Koehler, 1906. This work highlights the paucity of knowledge even in purportedly well-studied areas and in iconic Antarctic organisms.
The Spatial Distribution of Soil Nitrogen Storage and the Factors That Influence It in Central Asia’s Typical Arid and Semiarid Grasslands
Authors: Chen Yusen , Zhang Shihang , Wang Yongdong , Abzhanov Talgat , Sarsekova Dani , Zhumabekova Zhazira
Published: June 2022

Using a structural equation model (SEM), this paper investigates the response of soil nitrogen content of five typical grasslands in the middle line countries of China’s “Belt and Road” initiative to the changes of climate variables, soil pH value, and normalized vegetation index, and employs the principal component analysis method to determine the spatial variation characteristics and influencing factors of nitrogen reserves in different grasslands. Pontiac grassland (PS), Middle East grassland (MES), Kazakh grassland (KS), Kazakh forest grassland (KFS), and Kazakh semi-desert grassland (KFS) are the five grasslands in the research region (KSD). The results indicated that (1) the nitrogen reserves of the five grassland soils (0–100 cm) in the research area were 7.49 Pg, or approximately 5.7 percent of the total world nitrogen reserves. The sum of the five grasslands’ 0–30 cm and 0–50 cm N reserves accounted for 36.3 percent and 63.1 percent, respectively, of the total 0–100 cm N reserves. The density of nitrogen in the soil (0–100 cm) varied significantly between grasslands, ranging from 1.47 to 3.87 kg/m2, with an average of 3.10 kg/m2. (2) PCA analysis revealed a substantial positive correlation between soil N and MAP (p < 0.01), a negative correlation between soil N and Srad (p < 0.01), and a high degree of similarity between the three grassland samples, KFS, KS, and KSD. (3) The decision tree algorithm determined that MAP had the most relative importance for changes in soil nitrogen content in PS, MES, and KFS, whereas Srad had the greatest relative importance for changes in soil nitrogen content in KS and KSD. The pH showed the least proportional impact for variations in soil N concentration in all five grasslands. (4) Different factors influence the change in soil N content across diverse grasslands. The principal positive driving factor of soil N content in KS and KSD is Srad, with loads of −0.39 and −0.44, respectively. The principal negative driving factor of soil N content in PS and MES is Map, with loads of 0.38 and 0.2, respectively. In the SEM model of soil nitrogen content in KFS, no environmental variables had a significant effect on N content, and the model’s R2 value was 0.08, indicating an average fit.
Entomopathogenic Fungi in the Soils of China and Their Bioactivity against Striped Flea Beetles Phyllotretastriolata
Authors: Zhang Ke , Zhang Xiaofeng , Hu Qiongbo , Weng Qunfang
Published: June 2022

The present research aims to explore the occurrence and diversity of entomopathogenic fungi (EPF) in cultivated and uncultivated lands from different provinces of China and to search for EPF against Phyllotreta striolata. In this study, first, the EPF biodiversity from the soil of four provinces (Hunan, Hubei, Henan and Hebei) was surveyed. There were 302 fungal isolates obtained from 226 soil samples collected from croplands (114), arbor (79), grasslands (97) and fallow land (12); 188 EPF isolates were identified as 11 genera. The data indicate that Hubei Province has the greatest EPF diversity, with a Shannon Evenness Index (SHEI) value of 0.88. Here, the grassland, arbor and cropland had an EPF diversity with SHEI values of 0.81, 0.86 and 0.76, respectively, while the fallow land had the highest SHEI value of 1.00, which suggests that cultivation by humans affected the count and richness of soil fungi: the less human activity, the more kinds of fungi found. Finally, the pathogenicity of 47 fungal strains against the adult P. striolata was determined. Isaria javanica (IsjaHN3002) had the highest mortality. In conclusion, this study reports the EPF distribution and biodiversity in the soil from four provinces in China, showing that the amount and type of fungi in the soil varied by region and vegetation and that soil was one of the resources for acquiring EPF. The potential of I. javanica as a biocontrol must be studied further.
The Gerromorpha (Heteroptera: Gerridae, Mesoveliidae, Veliidae) of Mangroves of Central and Eastern Regions, Thailand
Authors: Nakthong La-au , Vitheepradit Akekawat
Published: June 2022

The Gerromorpha assemblages in mangroves located in the central and eastern regions of Thailand were examined, and a total of nine species belonging to six genera and three families were discovered. Four of the recorded species are new records for Thailand. Asclepios annandalei Distant, 1915 was the most common species and widely distributed throughout the study area. The most diverse genus was Xenobates, which consisted of Xenobates argentatus Andersen, 2000, Xenobates mandai Andersen, 2000, Xenobates murphyi Andersen, 2000, and Xenobates singaporensis Andersen, 2000. Three of these species are new country records. Here, we present taxonomic and ecological information of mangrove gerromorphans in the central and eastern regions of Thailand.
Can We Use the Oculus Quest VR Headset and Controllers to Reliably Assess Balance Stability?
Authors: Craig Cathy M. , Stafford James , Egorova Anastasiia , McCabe Carla , Matthews Mark
Published: June 2022

Balance is the foundation upon which all other motor skills are built. Indeed, many neurological diseases and injuries often present clinically with deficits in balance control. With recent advances in virtual reality (VR) hardware bringing low-cost headsets into the mainstream market, the question remains as to whether this technology could be used in a clinical context to assess balance. We compared the head tracking performance of a low-cost VR headset (Oculus Quest) with a gold standard motion tracking system (Qualisys). We then compared the recorded head sway with the center of pressure (COP) measures collected from a force platform in different stances and different visual field manipulations. Firstly, our analysis showed that there was an excellent correspondence between the two different head movement signals (ICCs > 0.99) with minimal differences in terms of accuracy (<5 mm error). Secondly, we found that head sway mapped onto COP measures more strongly when the participant adopted a Tandem stance during balance assessment. Finally, using the power of virtual reality to manipulate the visual input to the brain, we showed how the Oculus Quest can reliably detect changes in postural control as a result of different types of visual field manipulations. Given the high levels of accuracy of the motion tracking of the Oculus Quest headset, along with the strong relationship with the COP and ability to manipulate the visual field, the Oculus Quest makes an exciting alternative to traditional lab-based balance assessments.
Urine Proteome in Distinguishing Hepatic Steatosis in Patients with Metabolic-Associated Fatty Liver Disease
Authors: Liu Chang-Hai , Zheng Shanshan , Wang Shisheng , Wu Dongbo , Jiang Wei , Zeng Qingmin , Wei Yi , Zhang Yong , Tang Hong
Published: June 2022

Background: In patients with metabolic-associated fatty liver disease (MAFLD), hepatic steatosis is the first step of diagnosis, and it is a risk predictor that independently predicts insulin resistance, cardiovascular risk, and mortality. Urine biomarkers have the advantage of being less complex, with a lower dynamic range and fewer technical challenges, in comparison to blood biomarkers. Methods: Hepatic steatosis was measured by magnetic resonance imaging (MRI), which measured the proton density fat fraction (MRI-PDFF). Mild hepatic steatosis was defined as MRI-PDFF 5–10% and severe hepatic steatosis was defined as MRI-PDFF > 10%. Results: MAFLD patients with any kidney diseases were excluded. There were 53 proteins identified by mass spectrometry with significantly different expressions among the healthy control, mild steatosis, and severe steatosis patients. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of these significantly changed urinary molecular features correlated with the liver, resulting in the dysregulation of carbohydrate derivative/catabolic/glycosaminoglycan/metabolic processes, insulin-like growth factor receptor levels, inflammatory responses, the PI3K–Akt signaling pathway, and cholesterol metabolism. Urine alpha-1-acid glycoprotein 1 (ORM1) and ceruloplasmin showed the most significant correlation with the clinical parameters of MAFLD status, including liver fat content, fibrosis, ALT, triglycerides, glucose, HOMA-IR, and C-reactive protein. According to ELISA and western blot (30 urine samples, normalized to urine creatinine), ceruloplasmin (ROC 0.78, p = 0.034) and ORM1 (ROC 0.87, p = 0.005) showed moderate diagnostic accuracy in distinguishing mild steatosis from healthy controls. Ceruloplasmin (ROC 0.79, p = 0.028) and ORM1 (ROC 0.81, p = 0.019) also showed moderate diagnostic accuracy in distinguishing severe steatosis from mild steatosis. Conclusions: Ceruloplasmin and ORM1 are potential biomarkers in distinguishing mild and severe steatosis in MAFLD patients.