bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow Pattern Study and Pressure Drop Prediction of Two-Phase Boiling Process in Different Surface Wettability Microchannel
Authors: Zhang Yuqi , Wu Haoxian , Zhang Ling , Yang Yunbo , Niu Xiangdong , Zeng Zerong , Shu Bifen
Published: April 2023

An experimental study of two-phase flow pressure drop using R-134a is conducted on three types of different surface wettability microchannels with superhydrophilic (contact angle of 0°), hydrophilic (contact angle of 43°) and common (contact angle of 70°, unmodified) surfaces, all with a hydraulic diameter of 0.805 mm. Experiments were conducted using a mass flux of 713–1629 kg/m2s and a heat flux of 7.0–35.1 kW/m2. Firstly, the bubble behavior during the two-phase boiling process in the superhydrophilic and common surface microchannel is studied. Through a large number of flow pattern diagrams under different working conditions, it is found that the bubble behavior shows different degrees of order in microchannels with different surface wettability. The experimental results show that the hydrophilic surface modification of microchannel is an effective method to enhance heat transfer and reduce friction pressure drop. Through the data analysis of friction pressure drop and C parameter, it is found that the three most important parameters affecting the two-phase friction pressure drop are mass flux, vapor quality, and surface wettability. Based on flow patterns and pressure drop characteristics obtained from the experiments, a new parameter, named flow order degree, is proposed to account for the overall effects of mass flux, vapor quality, and surface wettability on two-phase frictional pressure drop in microchannels, and a newly developed correlation based on the separated flow model is presented. In the superhydrophilic microchannel, the mean absolute error of the new correlation is 19.8%, which is considerably less than the error of the previous models.
Performance Degradation Modeling and Its Prediction Algorithm of an IGBT Gate Oxide Layer Based on a CNN-LSTM Network
Authors: Wang Xin , Zhou Zhenwei , He Shilie , Liu Junbin , Cui Wei
Published: April 2023

The problem of health status prediction of insulated-gate bipolar transistors (IGBTs) has gained significant attention in the field of health management of power electronic equipment. The performance degradation of the IGBT gate oxide layer is one of the most important failure modes. In view of failure mechanism analysis and the easy implementation of monitoring circuits, this paper selects the gate leakage current of an IGBT as the precursor parameter of gate oxide degradation, and uses time domain characteristic analysis, gray correlation degree, Mahalanobis distance, Kalman filter, and other methods to carry out feature selection and fusion. Finally, it obtains a health indicator, characterizing the degradation of IGBT gate oxide. The degradation prediction model of the IGBT gate oxide layer is constructed by the Convolutional Neural Network and Long Short-Term Memory (CNN-LSTM) Network, which show the highest fitting accuracy compared with Long Short-Term Memory (LSTM), Convolutional Neural Network (CNN), Support Vector Regression (SVR), Gaussian Process Regression (GPR), and CNN-LSTM models in our experiment. The extraction of the health indicator and the construction and verification of the degradation prediction model are carried out on the dataset released by the NASA-Ames Laboratory, and the average absolute error of performance degradation prediction is as low as 0.0216. These results show the feasibility of the gate leakage current as a precursor parameter of IGBT gate oxide layer failure, as well as the accuracy and reliability of the CNN-LSTM prediction model.
Research on Energetic Micro-Self-Destruction Devices with Fast Responses
Authors: Kan Wenxing , Ren Jie , Feng Hengzhen , Lou Wenzhong , Li Mingyu , Zeng Qingxuan , Lv Sining , Su Wenting
Published: April 2023

Information self-destruction devices represent the last protective net available to realize information security. The self-destruction device proposed here can generate GPa-level detonation waves through the explosion of energetic materials and these waves can cause irreversible damage to information storage chips. A self-destruction model consisting of three types of nichrome (Ni-Cr) bridge initiators with copper azide explosive elements was first established. The output energy of the self-destruction device and the electrical explosion delay time were obtained using an electrical explosion test system. The relationships between the different copper azide dosages and the assembly gap between the explosive and the target chip with the detonation wave pressure were obtained using LS-DYNA software. The detonation wave pressure can reach 3.4 GPa when the dosage is 0.4 mg and the assembly gap is 0.1 mm, and this pressure can cause damage to the target chip. The response time of the energetic micro self-destruction device was subsequently measured to be 23.65 μs using an optical probe. In summary, the micro-self-destruction device proposed in this paper offers advantages that include low structural size, fast self-destruction response times, and high energy-conversion ability, and it has strong application prospects in the information security protection field.
Correction of Rotational Eccentricity Based on Model and Microvision in the Wire-Traction Micromanipulation System
Authors: Wang Yuezong , Qu Daoduo , Wang Shengyi , Chen Jiqiang , Qiu Lina
Published: April 2023

In the realm of automatic wire-traction micromanipulation systems, the alignment of the central axis of the coil with the rotation axis of the rotary stage can be a challenge, which leads to the occurrence of eccentricity during rotation. The wire-traction is conducted at a micron-level of manipulation precision on micron electrode wires; eccentricity has a significant impact on the control accuracy of the system. To resolve the problem, a method for measuring and correcting the coil eccentricity is proposed in this paper. First, models of radial and tilt eccentricity are established respectively based on the eccentricity sources. Then, measuring eccentricity is proposed by an eccentricity model and microscopic vision; the model is used to predict eccentricity, and visual image processing algorithms are used to calibrate model parameters. In addition, a correction based on the compensation model and hardware is designed to compensate for the eccentricity. The experimental results demonstrate the accuracy of the models in predicting eccentricity and the effectiveness of correction. The results show that the models have an accurate prediction for eccentricity that relies on the evaluation of the root mean square error (RMSE); the maximal residual error after correction was within 6 μm, and the compensation was approximately 99.6%. The proposed method, which combines the eccentricity model and microvision for measuring and correcting eccentricity, offers improved wire-traction micromanipulation accuracy, enhanced efficiency, and an integrated system. It has more suitable and wider applications in the field of micromanipulation and microassembly.
The Design and Experiment of a Spring-Coupling Electromagnetic Galloping Energy Harvester
Authors: Xiong Lei , Gao Shiqiao , Jin Lei , Guo Shengkai , Sun Yaoqiang , Liu Feng
Published: April 2023

In order to improve the output characteristics of the electromagnetic energy harvester in a high-speed flow field, a spring-coupling electromagnetic energy harvester (SEGEH) is proposed, based on the galloping characteristics of a large amplitude. The electromechanical model of the SEGEH was established, the test prototype was made, and the experiments were conducted using a wind tunnel platform. The coupling spring can convert the vibration energy consumed by the vibration stroke of the bluff body without inducing an electromotive force into the elastic energy of the spring. This not only reduces the galloping amplitude, but it also provides elastic force for the return of the bluff body, and it improves the duty cycle of the induced electromotive force and the output power of the energy harvester. The stiffness of the coupling spring and the initial distance between the coupling spring and the bluff body will affect the output characteristics of the SEGEH. At a wind speed of 14 m/s, the output voltage was 103.2 mV and the output power was 0.79 mW. Compared with the energy harvester without a coupling spring (EGEH), the output voltage increases by 29.4 mV, with an increase of 39.8%. The output power was increased by 0.38 mW, with an increase of 92.7%.
Haplosporidium pinnae Parasite Detection in Seawater Samples
Authors: Moro-Martínez Irene , Vázquez-Luis Maite , García-March José Rafael , Prado Patricia , Mičić Milena , Catanese Gaetano
Published: April 2023

In this study, we investigated the presence of the parasite Haplosporidium pinnae, which is a pathogen for the bivalve Pinna nobilis, in water samples from different environments. Fifteen mantle samples of P. nobilis infected by H. pinnae were used to characterize the ribosomal unit of this parasite. The obtained sequences were employed to develop a method for eDNA detection of H. pinnae. We collected 56 water samples (from aquaria, open sea and sanctuaries) for testing the methodology. In this work, we developed three different PCRs generating amplicons of different lengths to determine the level of degradation of the DNA, since the status of H. pinnae in water and, therefore, its infectious capacity are unknown. The results showed the ability of the method to detect H. pinnae in sea waters from different areas persistent in the environment but with different degrees of DNA fragmentation. This developed method offers a new tool for preventive analysis for monitoring areas and to better understand the life cycle and the spread of this parasite.
Mucosal Microbiota from Colorectal Cancer, Adenoma and Normal Epithelium Reveals the Imprint of Fusobacterium nucleatum in Cancerogenesis
Authors: Palmieri Orazio , Castellana Stefano , Latiano Anna , Latiano Tiziana , Gentile Annamaria , Panza Anna , Nardella Marianna , Ciardiello Davide , Latiano Tiziana Pia , Corritore Giuseppe , Mazza Tommaso , Perri Francesco , Biscaglia Giuseppe
Published: April 2023

An increasing amount of evidence suggests the emerging role of the gut microbiota in the development of colorectal cancer (CRC). This study aimed to elucidate the architecture of microbial communities within normal and neoplastic colonic mucosa. Methods: Microbiota were analyzed by NGS and by an ensemble of metagenomics analysis tools in a total of 69 tissues from 9 patients with synchronous colorectal neoplasia and adenomas (27 specimens: 9 from normal tissues, 9 adenomas, and 9 tumours), 16 patients with only colonic adenomas (32 specimens: 16 from normal tissues and 16 adenomas), and from healthy subjects (10 specimens of normal mucosa). Results: Weak differences were observed in alpha and beta metrics among the synchronous tissues from CRC and controls. Through pairwise differential abundance analyses of sample groups, an increasing trend of Rikenellaceae, Pseudomonas and Fusobacterium, and decreasing trends of Staphylococcus, Actinobacillus and Gemmiger were observed in CRC, while Staphylococcus and Bifidobacterium were decreased in patients with only adenomas. At RT-qPCR analysis, Fusobacterium nucleatum was significantly enriched in all the tissues of subjects with synchronous colorectal neoplasia. Conclusion: Our findings provide a comprehensive view of the human mucosa-associated gut microbiota, emphasizing global microbial diversity mostly in synchronous lesions and proving the constant presence of Fusobacterium nucleatum, with its ability to drive carcinogenesis.
Invasive Candida parapsilosis Bloodstream Infections in Children: The Antifungal Susceptibility, Clinical Characteristics and Impacts on Outcomes
Authors: Wang Yao-Sheng , Hsu Jen-Fu , Lee Wei-Ju , Wang Shao-Hung , Chu Shih-Ming , Huang Hsuan-Rong , Yang Peng-Hong , Fu Ren-Huei , Tsai Ming-Horng
Published: April 2023

Background: Candida parapsilosis is the most common non-albicans candida species that causes invasive candidiasis, but little is known about its impacts on the outcomes of pediatric patients. We aimed to characterize the clinical characteristics, risk factors and outcomes of C. parapsilosis bloodstream infections (BSIs) in children. Methods: All pediatric patients with Candida parapsilosis BSIs between 2005 and 2020 from a medical center in Taiwan were enrolled and analyzed. The antifungal susceptibility, clinical manifestations, management and outcomes were investigated. Cases of Candida parapsilosis BSIs were compared between patients with C. albicans BSIs and other Candida spp. BSIs. Results: During the study period, 95 episodes (26.0% of total cases) of Candida parapsilosis BSIs were identified and analyzed. No significant difference was found between pediatric patients with C. parapsilosis BSIs and those with C. albicans BSIs in terms of patients’ demographics, most chronic comorbidities or risk factors. Pediatric patients with C. parapsilosis BSIs were significantly more likely to have previous azole exposure and be on total parenteral nutrition than those with C. albicans BSIs (17.9 vs. 7.6% and 76.8 vs. 63.7%, p = 0.015 and 0.029, respectively). The duration of C. parapsilosis candidemia was relatively longer, and therefore patients often required a longer duration of antifungal treatment when compared with those of C. albicans candidemia, although the candidemia-attributable mortality rates were comparable. Of the C. parapsilosis isolates, 93.7% were susceptible to all antifungal agents, and delayed appropriate antifungal treatment was an independent factor in treatment failure. Conclusions: Pediatric patients with C. parapsilosis BSIs were more likely to have previous azole exposure and be on total parenteral nutrition, and the clinical significances included a longer duration of candidemia and patients often required a longer duration of antifungal treatment.
Microbiota Assessment of Fresh-Cut Apples Packaged in Two Different Films
Authors: Madureira Joana , Gonçalves Sara , Santos-Buelga Celestino , Margaça Fernanda M. A. , Ferreira Isabel C. F. R. , Barros Lillian , Cabo Verde Sandra
Published: April 2023

The aim of this work was to assess the natural microbiota of packed fresh-cut apples during refrigerated storage. Two different films were tested for the package, a biodegradable (PLA) film and a conventional and commercial one (OPP). Two antioxidant additives were applied, a natural olive pomace extract and the commercial ascorbic acid used by the industries. The results revealed lower bacteria counts in samples with olive pomace extract and PLA films than in those with ascorbic acid and OPP films after 5 and 12 days of storage. These findings suggest that the use of such natural extracts as additives in fruits could delay the growth of mesophilic bacteria. The characterization and identification of the bacterial isolates from fresh-cut apple samples showed that the most prevalent species were Citrobacter freundii, Staphylococcus warneri, Pseudomonas oryzihabitans, Alcalinogenes faecalis, Corynebacterium jeikeium, Micrococcus spp., Pantoea aglomerans and Bacillus spp. Furthermore, an increase in the microbial diversity during the storage time at refrigerated temperatures was observed, except for the sample treated with olive pomace extract and packaged in OPP film. The highest microbial diversity was found for samples with ascorbic acid as an additive. This could indicate a negative effect of ascorbic acid on the microbial inhibition of apple slices. The natural olive pomace extract demonstrated potential as an antimicrobial additive for fresh-cut apples.
Application of Logistic Regression and Weights of Evidence Methods for Mapping Volcanic-Type Uranium Prospectivity
Authors: Zhao Jiangnan , Sui Yu , Zhang Zongyao , Zhou Mi
Published: April 2023

Pucheng district is a part of the Wuyi Mountain polymetallic metallogenic belt, which is constituted by Archean-Proterozoic metamorphic basements and Mesozoic volcanic-sedimentary covers. Uranium deposits are formed as volcanic-hosted and structural controls. In this study, the hybrid data-driven methods of logistic regression (LR) and weights of evidence (WofE) were applied for the mineral potential mapping of uranium in the Pucheng district. Evidential layers such as volcanic stratum, structure, igneous rock, alteration and radioactive anomaly were used in the mineral prospectivity analyses. The results show that the data-driven methods can not only measure the relative importance of each type of geological feature in uranium controls but also delineate prospective grounds for uranium exploration. The receiver operating characteristics (ROC) curve and under the ROC curve (AUC) were applied to measure the performance of the prospectivity models. The data-driven models are highly capable of mapping uranium prospectivity because AUC is close to 1. The results show that more than 90% of the known uranium deposits occur in regions with high probability. LR performs a little better than WofE in this area. The prospectivity mapping confirmed that there is significant potential for uranium mineralization for further exploration.
Sorption of Natural Siderophores onto Clinoptilolite-Tuff and Its Controlled-Release Characteristics
Authors: Haemmerle Mona M. , Tschegg Cornelius
Published: April 2023

Iron deficiency-induced chlorosis is a widespread horti-/agricultural problem that can lead to massive crop failures, especially for plants growing on calcareous soils. The most effective agronomical practice to prevent plants from iron deficiency is to apply synthetic Fe-(chelate)-fertilizers to the soil. Because these compounds are usually not biodegradable and, therefore, may become soil contaminants, efficient and environmentally friendly solutions are needed. The present study investigates a novel approach to tackle chlorosis in plants using clinoptilolite-tuff as a carrier substrate for the natural Fe-siderophore ‘coprogen’. The combination of the two substances promises economic and ecological potential to be used as a fertilizer to prevent crop failures triggered by micro-nutritional shortages. Sorption and release experiments were performed in batch and column setups in order to understand the binding characteristics; analyses were carried out using ICP-MS, HPLC, XRD, and SEM, respectively. Results show the highest sorption capacity of coprogen (92.8%) and corresponding Fe (90.2%) on clinoptilolite-tuff at pH 4 within 30 min as well as the efficient release of coprogen at pH 8, mimicking alkaline soil conditions (88% of the sorbed coprogen is released from the tuff). The gained data suggest that coprogen is bound onto the clinoptilolite-tuff through surface-mediated sorption based on electrostatic interactions.
Investigations of Monomineralic Flotation of Galena, Sphalerite, and Pyrite at Different Temperatures
Authors: Pashkevich Dzmitry , Li Ronghao , Kökkılıç Ozan , Waters Kristian Edmund
Published: April 2023

Temperature variations could potentially impact flotation performance, leading to operational and economic issues. Several historical and currently operating plants across Canada have reported seasonal metal losses as one of their major challenges. Improvements in flotation efficiency at cold temperatures are important for the sustainable development of the industry, especially in view of expanding mining operations to the north and the increasing impact of climate change-originated weather extremes on mining operations. To better understand the driving mechanisms of the seasonal metallurgical variation, the degree of vulnerability of froth flotation to fluctuations in temperature, and to develop recommendations addressing seasonally driven losses, a series of mono-mineral flotation tests were conducted. The observed variations in yield and recovery kinetics for different sulfide minerals follow a similar pattern: higher recovery and slower kinetics at lower temperatures, and lower recoveries and faster kinetics at higher temperature conditions. Following the results of the flotation tests, foam height and stability were investigated at different temperatures to explain the observed variations. A high correlation between changes in mono-mineral flotation behavior and foam properties with temperature was revealed.
Isotopic Signatures of Microbial Mg-Carbonates Deposited in an Ephemeral Hyperalkaline Lake (Central Spain): Paleoenvironmental Implications
Authors: Sanz-Montero María E. , del Buey Pablo , Cabestrero Óscar , Sánchez-Román Mónica
Published: April 2023

Interpretation of stable isotope (C and O) composition of lacustrine carbonates requires in-depth knowledge about the interplay between the abiotic and biotic processes in sedimentary environments. The present study, focused on Mg-carbonates from a well-characterized alkaline and ephemeral lake, gives new insight into the behavior of the stable isotopes during the seasonal precipitation of a variety of carbonates. Dolomite and Mg-calcite precipitate intracellularly within Spirogyra during spring and show lighter isotopic signatures (δ13C aver. −4.10‰ and δ18O aver. −0.75‰, VPDB) than a second association of carbonates, such as hydromagnesite, northupite and traces of magnesite among other sodium-bearing carbonates (δ13C aver., −1.34‰ and δ18O aver. 4.52‰, VPDB). The latter precipitate in association with degraded microbial mats as the lake desiccates during summer. Covariant trends between carbonate δ13C and δ18O reflect isotope enrichment related to evapoconcentration. The seasonal cycling of inorganic carbon among carbonate minerals, microbial biomass, lake water and pore water was also analyzed, revealing variations of δ13C within a range of −12.40‰ to −0.43‰. The more depleted 13C derives from the decay of the microbial mats. The less negative values are distinctive of the bulk carbonates forming crusts in summer. Intracellular calcite and dolomite have δ13C and δ18O values (VPDB) ranging, from −5.45‰ to −3.07‰ and −2.48‰ to 1.58‰, respectively, that are intermediate between those two endmembers. These intracellular carbonates are enriched in 13C by 5‰ with respect to dissolved inorganic carbon (δ13C in the range of −11.79‰ to −6.87‰, VPDB) due to the vital effect of photosynthesis. The crust of carbonates deposited as the lake desiccates dissolve interannually. Alternatively, dolomite and Mg-calcite as well as their isotopic compositions persist during synsedimentary diagenesis, confirming that carbonate biominerals provide isotopic signatures related to the environmental conditions of formation with potential of preservation in the rock record.
Impact of Solid Hydrocarbon on the Composition of Fluid Phase at the Subduction (Experimental Simulation)
Authors: Tomilenko Anatoly , Sonin Valeriy , Bul’bak Taras , Zhimulev Egor , Timina Tatiana , Chepurov Aleksey , Shaparenko Elena , Chepurov Anatoly
Published: April 2023

Experiments conducted in the olivine–serpentine–anthracene–metal (FeNi) system have shown that the recrystallization of olivines occurs under substantially reduced conditions with active participation of hydrocarbons, especially paraffins; moreover, their amount increases with increasing pressure and temperature. During the decomposition of serpentine, a large amount of water is released; therefore, the fluid at relatively low P-T parameters (2 GPa, 1100 °C) has mainly water–hydrocarbon composition. With an increase in pressure up to 3–4.5 GPa and temperature up to 1300–1400 °C, the composition of the fluid changes greatly towards an increase in the relative amount of hydrocarbons, while the main share is occupied by light (C1–C4) aliphatic hydrocarbons. Therefore, a biogenic material with a carbon–hydrogen composition can make a certain contribution to the carbon budget in subduction processes when falling into the subduction zones and may affect the oxygen fugitivity in the subducted slab.
Simultaneous Preparation of Chitin and Flavor Protein Hydrolysates from the By-Products of Shrimp Processing by One-Step Fermentation with Lactobacillus fermuntum
Authors: Li Jiawei , Song Ru , Zou Xiaoyu , Wei Rongbian , Wang Jiaxing
Published: April 2023

One-step fermentation, inoculated with Lactobacillus fermentum (L. fermentum) in shrimp by-products, was carried out to obtain chitin and flavor protein hydrolysates at the same time. The fermentation conditions were optimized using response surface methodology, resulting in chitin with a demineralization rate of 89.48%, a deproteinization rate of 85.11%, and a chitin yield of 16.3%. The surface of chitin after fermentation was shown to be not dense, and there were a lot of pores. According to Fourier transform infrared spectroscopy and X-ray diffraction patterns, the fermented chitin belonged to α-chitin. More than 60 volatiles were identified from the fermentation broth after chitin extraction using gas chromatography–ion transfer spectrometry analysis. L. fermentum fermentation decreased the intensities of volatile compounds related to unsaturated fatty acid oxidation or amino acid deamination. By contrast, much more pleasant flavors related to fruity and roasted aroma were all enhanced in the fermentation broth. Our results suggest an efficient one-step fermentation technique to recover chitin and to increase aroma and flavor constituents from shrimp by-products.
Spontaneous In-Source Fragmentation Reaction Mechanism and Highly Sensitive Analysis of Dicofol by Electrospray Ionization Mass Spectrometry
Authors: Xie Jun , Guo Yage , Ma Yongqiang , Jiang Hongyun , Zhang Lan , Mao Liangang , Zhu Lizhen , Zheng Yongquan , Liu Xingang
Published: April 2023

Although dicofol has been widely banned all over the world as a kind of organochlorine contaminant, it still exists in the environment. This study developed a high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) detection technique for dicofol, an environmental pollutant, for the first time using in-source fragmentation. The results confirmed that m/z 251 was the only precursor ion of dicofol after in-source fragmentation, and m/z 139 and m/z 111 were reasonable product ions. The main factors triggering the in-source fragmentation were the H+ content and solution conductivity when dicofol entered the mass spectrometer. Density functional theory can be used to analyze and interpret the mechanism of dicofol fragmentation reaction in ESI source. Dicofol reduced the molecular energy from 8.8 ± 0.05 kcal/mol to 1.0 ± 0.05 kcal/mol, indicating that the internal energy release from high to low was the key driving force of in-source fragmentation. A method based on HPLC-MS/MS was developed to analyze dicofol residues in environmental water. The LOQ was 0.1 μg/L, which was better than the previous GC or GC-MS methods. This study not only proposed an HPLC-MS/MS analysis method for dicofol for the first time but also explained the in-source fragmentation mechanism of compounds in ESI source, which has positive significance for the study of compounds with unconventional mass spectrometry behavior in the field of organic pollutant analysis and metabonomics.
In Silico and In Vitro Assessment of Carbonyl Reductase 1 Inhibition Using ASP9521—A Potent Aldo-Keto Reductase 1C3 Inhibitor with the Potential to Support Anticancer Therapy Using Anthracycline Antibiotics
Authors: Jamrozik Marek , Piska Kamil , Bucki Adam , Koczurkiewicz-Adamczyk Paulina , Sapa Michał , Władyka Benedykt , Pękala Elżbieta , Kołaczkowski Marcin
Published: April 2023

Anthracycline antibiotics (ANT) are among the most widely used anticancer drugs. Unfortunately, their use is limited due to the development of drug resistance and cardiotoxicity. ANT metabolism, performed mainly by two enzymes—aldo-keto reductase 1C3 (AKR1C3) and carbonyl reductase 1 (CBR1)—is one of the proposed mechanisms generated by the described effects. In this study, we evaluated the CBR1 inhibitory properties of ASP9521, a compound already known as potent AKR1C3 inhibitor. First, we assessed the possibility of ASP9521 binding to the CBR1 catalytic site using molecular docking and molecular dynamics. The research revealed a potential binding mode of ASP9521. Moderate inhibitory activity against CBR1 was observed in studies with recombinant enzymes. Finally, we examined whether ASP9521 can improve the cytotoxic activity of daunorubicin against human lung carcinoma cell line A549 and assessed the cardioprotective properties of ASP9521 in a rat cardiomyocytes model (H9c2) against doxorubicin- and daunorubicin-induced toxicity. The addition of ASP9521 ameliorated the cytotoxic activity of daunorubicin and protected rat cardiomyocytes from the cytotoxic effect of both applied drugs. Considering the favorable bioavailability and safety profile of ASP9521, the obtained results encourage further research. Inhibition of both AKR1C3 and CBR1 may be a promising method of overcoming ANT resistance and cardiotoxicity.
Functional Nanomaterials Enhancing Electrochemical Biosensors as Smart Tools for Detecting Infectious Viral Diseases
Authors: Curulli Antonella
Published: April 2023

Electrochemical biosensors are known as analytical tools, guaranteeing rapid and on-site results in medical diagnostics, food safety, environmental protection, and life sciences research. Current research focuses on developing sensors for specific targets and addresses challenges to be solved before their commercialization. These challenges typically include the lowering of the limit of detection, the widening of the linear concentration range, the analysis of real samples in a real environment and the comparison with a standard validation method. Nowadays, functional nanomaterials are designed and applied in electrochemical biosensing to support all these challenges. This review will address the integration of functional nanomaterials in the development of electrochemical biosensors for the rapid diagnosis of viral infections, such as COVID-19, middle east respiratory syndrome (MERS), influenza, hepatitis, human immunodeficiency virus (HIV), and dengue, among others. The role and relevance of the nanomaterial, the type of biosensor, and the electrochemical technique adopted will be discussed. Finally, the critical issues in applying laboratory research to the analysis of real samples, future perspectives, and commercialization aspects of electrochemical biosensors for virus detection will be analyzed.
Ethanol Coupling Reactions over MgO–Al2O3 Mixed Oxide-Based Catalysts for Producing Biofuel Additives
Authors: Vikár Anna , Lónyi Ferenc , Makoye Amosi , Nagy Tibor , Novodárszki Gyula , Barthos Róbert , Szabó Blanka , Valyon József , Mihályi Magdolna R. , Deka Dhanapati , Solt Hanna E.
Published: April 2023

Catalytic conversion of ethanol to 1-butanol was studied over MgO–Al2O3 mixed oxide-based catalysts. Relationships between acid-base and catalytic properties and the effect of active metal on the hydrogen transfer reaction steps were investigated. The acid-base properties were studied by temperature-programmed desorption of CO2 and NH3 and by the FT-IR spectroscopic examination of adsorbed pyridine. Dispersion of the metal promoter (Pd, Pt, Ru, Ni) was determined by CO pulse chemisorption. The ethanol coupling reaction was studied using a flow-through microreactor system, He or H2 carrier gas, WHSV = 1 gEtOH·gcat.−1·h−1, at 21 bar, and 200–350 °C. Formation and transformation of surface species under catalytic conditions were studied by DRIFT spectroscopy. The highest butanol selectivity and yield was observed when the MgO–Al2O3 catalyst contained a relatively high amount of strong-base and medium-strong Lewis acid sites. The presence of metal improved the activity both in He and H2; however, the butanol selectivity significantly decreased at temperatures ≥ 300 °C due to acceleration of undesired side reactions. DRIFT spectroscopic results showed that the active metal promoted H-transfer from H2 over the narrow temperature range of 200–250 °C, where the equilibrium allowed significant concentrations of both dehydrogenated and hydrogenated products.
Silver Ion High-Performance Liquid Chromatography—Atmospheric Pressure Chemical Ionization Mass Spectrometry: A Tool for Analyzing Cuticular Hydrocarbons
Authors: Vrkoslav Vladimír , Horká Petra , Jindřich Jindřich , Buděšínský Miloš , Cvačka Josef
Published: April 2023

Aliphatic hydrocarbons (HCs) are usually analyzed by gas chromatography (GC) or matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. However, analyzing long-chain HCs by GC is difficult because of their low volatility and the risk of decomposition at high temperatures. MALDI cannot distinguish between isomeric HCs. An alternative approach based on silver ion high-performance liquid chromatography (Ag-HPLC) is shown here. The separation of HC standards and cuticular HCs was accomplished using two ChromSpher Lipids columns connected in series. A gradient elution of the analytes was optimized using mobile phases prepared from hexane (or isooctane) and acetonitrile, 2-propanol, or toluene. HCs were detected by atmospheric pressure chemical ionization mass spectrometry (APCI-MS). Good separation of the analytes according to the number of double bonds, cis/trans geometry, and position of double bonds was achieved. The retention times increased with the number of double bonds, and trans isomers eluted ahead of cis isomers. The mobile phase significantly affected the mass spectra of HCs. Depending on the mobile phase composition, deprotonated molecules, molecular ions, protonated molecules, and various solvent-related adducts of HCs were observed. The optimized Ag-HPLC/APCI-MS was applied for characterizing cuticular HCs from a flesh fly, Neobellieria bullata, and cockroach, Periplaneta americana. The method made it possible to detect a significantly higher number of HCs than previously reported for GC or MALDI-MS. Unsaturated HCs were frequently detected as isomers differing by double-bond position(s). Minor HCs with trans double bonds were found beside the prevailing cis isomers. Ag-HPLC/APCI-MS has great potential to become a new tool in chemical ecology for studying cuticular HCs.
Enhancing Efficiency of Natural Product Structure Revision: Leveraging CASE and DFT over Total Synthesis
Authors: Elyashberg Mikhail , Tyagarajan Sriram , Mandal Mihir , Buevich Alexei V.
Published: April 2023

Natural products remain one of the major sources of coveted, biologically active compounds. Each isolated compound undergoes biological testing, and its structure is usually established using a set of spectroscopic techniques (NMR, MS, UV-IR, ECD, VCD, etc.). However, the number of erroneously determined structures remains noticeable. Structure revisions are very costly, as they usually require extensive use of spectroscopic data, computational chemistry, and total synthesis. The cost is particularly high when a biologically active compound is resynthesized and the product is inactive because its structure is wrong and remains unknown. In this paper, we propose using Computer-Assisted Structure Elucidation (CASE) and Density Functional Theory (DFT) methods as tools for preventive verification of the originally proposed structure, and elucidation of the correct structure if the original structure is deemed to be incorrect. We examined twelve real cases in which structure revisions of natural products were performed using total synthesis, and we showed that in each of these cases, time-consuming total synthesis could have been avoided if CASE and DFT had been applied. In all described cases, the correct structures were established within minutes of using the originally published NMR and MS data, which were sometimes incomplete or had typos.
Study on the Enhancement Effect of Synergy between Multi-Size Functionalized Boron Nitride and Graphene Oxide on the Thermal Properties of Phase Change Composites
Authors: Xin Song , Zhao Zhiwen , Liu Shangxiao , Liu Jiedong , Li Mengya
Published: April 2023

Boron nitride nanosheet (BNNS) and graphene oxide (GO) as a single filler can effectively improve the thermal conductivity of the composites, and the synergistic mechanism of BNNS and GO was investigated in this paper. In this study, BNNS was first surface-functionalized and the multi-sized (50 nm, 200 nm, 500 nm) modified BNNS (A-BN) were attached to GO through non-covalent bonding interactions to form a cross-linked structure. Then, A-BN and GO were used as thermal fillers and support material adsorption eutectic phase change materials (PCMs) to prepare composite phase change material (CPCM). Characterization results show that small-size A-BN was more likely to form dense thermal networks with good compatibility and interface connectivity between PCMs, A-BN, and GO, ensuring that PCMs can be stored in the network without leaking. When the size of the BNNS was greater than 200 nm, the advantage of thermal conductivity obtained by A-BN was no longer obvious, and the phase change behavior of CPCM was inhibited. In general, the prepared CPCM has the ideal thermal response and thermal stability, which is very suitable for energy storage and thermal management applications.
Anti-Inflammatory Effect of Ethanolic Extract from Tabebuia rosea (Bertol.) DC., Quercetin, and Anti-Obesity Drugs in Adipose Tissue in Wistar Rats with Diet-Induced Obesity
Authors: Barrios-Nolasco Alejandro , Domínguez-López Aarón , Miliar-García Angel , Cornejo-Garrido Jorge , Jaramillo-Flores María Eugenia
Published: April 2023

Obesity is characterized by the excessive accumulation of fat, which triggers a low-grade chronic inflammatory process. Currently, the search for compounds with anti-obesogenic effects that help reduce body weight, as well as associated comorbidities, continues. Among this group of compounds are plant extracts and flavonoids with a great diversity of action mechanisms associated with their beneficial effects, such as anti-inflammatory effects and/or as signaling molecules. In the bark of Tabebuia rosea tree, there are different classes of metabolites with anti-inflammatory properties, such as quercetin. Therefore, the present work studied the effect of the ethanolic extract of T. rosea and quercetin on the mRNA of inflammation markers in obesity compared to the drugs currently used. Total RNA was extracted from epididymal adipose tissue of high-fat diet-induced obese Wistar rats treated with orlistat, phentermine, T. rosea extract, and quercetin. The rats treated with T. rosea and quercetin showed 36 and 31% reductions in body weight compared to the obese control, and they likewise inhibited pro-inflammatory molecules: Il6, Il1b, Il18, Lep, Hif1a, and Nfkb1 without modifying the expression of Socs1 and Socs3. Additionally, only T. rosea overexpressed Lipe. Both T. rosea and quercetin led to a reduction in the expression of pro-inflammatory genes, modifying signaling pathways, which led to the regulation of the obesity-inflammation state.
Essential and Potentially Toxic Elements (PTEs) Content in European Tea (Camellia sinensis) Leaves: Risk Assessment for Consumers
Authors: Girolametti Federico , Annibaldi Anna , Illuminati Silvia , Damiani Elisabetta , Carloni Patricia , Truzzi Cristina
Published: April 2023

Tea (Camellia sinensis) is the second most consumed beverage worldwide, playing a key role in the human diet. Tea is considered a healthy drink, as its consumption has been linked to a lower risk of cardiovascular disease-related events and death, stroke, metabolic syndrome and obesity. However, several studies have shown that C. sinensis is a hyperaccumulator of Al and other elements that are considered potentially toxic. In the present study, the contents of 15 elements (both essential and toxic) were determined for the first time in tea leaves collected in tea gardens located in six different European countries and processed to provide black and green tea. The results showed that Al was the major toxic element detected, followed by Ni, Cr, Pb, As, Cd, Ag, and Hg. Essential elements were detected in the order of Mn, Fe, Zn, Cu, Co, and Se. Statistically significant correlations (p < 0.05) were found in the distribution of some elements, highlighting mechanisms of synergic or antagonist interaction. Multivariate analysis revealed that geographical origin was the main driver in clustering the samples, while the different treatment processes (black or green) did not significantly affect the contents of elements in the leaves. The estimation of potential non-carcinogenic risk revealed no risk for the consumption of European teas for consumers in terms of potentially toxic elements.
A Modified Wet Transfer Method for Eliminating Interfacial Impurities in Graphene
Authors: Jang Dong Jin , Haidari Mohd Musaib , Kim Jin Hong , Ko Jin-Yong , Yi Yoonsik , Choi Jin Sik
Published: April 2023

Graphene has immense potential as a material for electronic devices owing to its unique electrical properties. However, large-area graphene produced by chemical vapor deposition (CVD) must be transferred from the as-grown copper substrate to an arbitrary substrate for device fabrication. The conventional wet transfer technique, which uses FeCl3 as a Cu etchant, leaves microscale impurities from the substrate, and the etchant adheres to graphene, thereby degrading its electrical performance. To address this limitation, this study introduces a modified transfer process that utilizes a temporary UV-treated SiO2 substrate to adsorb impurities from graphene before transferring it onto the final substrate. Optical microscopy and Raman mapping confirmed the adhesion of impurities to the temporary substrate, leading to a clean graphene/substrate interface. The retransferred graphene shows a reduction in electron–hole asymmetry and sheet resistance compared to conventionally transferred graphene, as confirmed by the transmission line model (TLM) and Hall effect measurements (HEMs). These results indicate that only the substrate effects remain in action in the retransferred graphene, and most of the effects of the impurities are eliminated. Overall, the modified transfer process is a promising method for obtaining high-quality graphene suitable for industrial-scale utilization in electronic devices.
Long-Term Antibacterial Efficacy of Cetylpyridinium Chloride-Montmorillonite Containing PMMA Resin Cement
Authors: Yoshihara Kumiko , Nagaoka Noriyuki , Makita Yoji , Yoshida Yasuhiro , Van Meerbeek Bart
Published: April 2023

Despite being able to adhesively restore teeth, adhesives and cement do not possess any anticariogenic protection potential, by which caries recurrence may still occur and reduce the clinical lifetime of adhesive restorations. Several antibacterial agents have been incorporated into dental adhesives and cement to render them anticariogenic. Due to an additional therapeutic effect, such materials are classified as ‘dental combination products’ with more strict market regulations. We incorporated cetylpyridinium chloride (CPC), often used for oral hygiene applications, into montmorillonite (CPC-Mont), the latter to serve as a carrier for controlled CPC release. CPC-Mont incorporated into tissue conditioner has been approved by the Pharmaceuticals and Medical Devices Agency (PmontMDA) in Japan. To produce a clinically effective dental cement with the antibacterial potential to prevent secondary caries, we incorporated CPC-Mont into PMMA resin cement. We measured the flexural strength, shear bond strength onto dentin, CPC release, and the biofilm-inhibition potential of the experimental CPC-Mont-containing PMMA cement. An 8 and 10 wt% CPC-Mont concentration revealed the antibacterial potential without reducing the mechanical properties of the PMMA cement.
Evolutionary Progress of Silica Aerogels and Their Classification Based on Composition: An Overview
Authors: Meti Puttavva , Wang Qi , Mahadik D. B. , Lee Kyu-Yeon , Gong Young-Dae , Park Hyung-Ho
Published: April 2023

Aerogels are highly porous materials with fascinating properties prepared using sol-gel chemistry. Due to their unique physical and chemical properties, aerogels are recognized as potential candidates for diverse applications, including thermal insulation, sensor, environmental remediation, etc. Despite these applications, aerogels are not routinely found in our daily life because they are fragile and have highly limited scale-up productions. It remains extremely challenging to improve the mechanical properties of aerogels without adversely affecting their other properties. To boost the practical applications, it is necessary to develop efficient, low-cost methods to produce aerogels in a sustainable way. This comprehensive review surveys the progress in the development of aerogels and their classification based on the chemical composition of the network. Recent achievements in organic, inorganic, and hybrid materials and their outstanding physical properties are discussed. The major focus of this review lies in approaches that allow tailoring of aerogel properties to meet application-driven requirements. We begin with a brief discussion of the fundamental issues in silica aerogels and then proceed to provide an overview of the synthesis of organic and hybrid aerogels from various precursors. Organic aerogels show promising results with excellent mechanical strength, but there are still several issues that need further exploration. Finally, growing points and perspectives of the aerogel field are summarized.
Role of Hydrogen in Ethylene-Based Synthesis of Single-Walled Carbon Nanotubes
Authors: Bogdanova Alisa R. , Krasnikov Dmitry V. , Khabushev Eldar M. , Ramirez B. Javier A. , Matyushkin Yakov E. , Nasibulin Albert G.
Published: April 2023

We examined the effect of hydrogen on the growth of single-walled carbon nanotubes in the aerosol (a specific case of the floating catalyst) chemical vapor deposition process using ethylene as a carbon source and ferrocene as a precursor for a Fe-based catalyst. With a comprehensive set of physical methods (UV-vis-NIR and Raman spectroscopies, transmission electron microscopy, scanning electron microscopy, differential mobility analysis, and four-probe sheet resistance measurements), we showed hydrogen to inhibit ethylene pyrolysis extending the window of synthesis parameters. Moreover, the detailed study at different temperatures allowed us to distinguish three different regimes for the hydrogen effect: pyrolysis suppression at low concentrations (I) followed by surface cleaning/activation promotion (II), and surface blockage/nanotube etching (III) at the highest concentrations. We believe that such a detailed study will help to reveal the complex role of hydrogen and contribute toward the synthesis of single-walled carbon nanotubes with detailed characteristics.
Advanced Nanomaterials for Quantum Technology, Sensor and Health Therapy Applications
Authors: Baskoutas Sotirios
Published: April 2023

The intense interest in nanostructured materials is fueled by the tremendous economic and technological benefits anticipated to be achieved by nanotechnology and nanodevices [...]
Risk Assessment of Nanomaterials Toxicity
Authors: Hartwig Andrea , van Thriel Christoph
Published: April 2023

The increasing use of nanomaterials in almost every area of our daily life renders toxicological risk assessment a major requirement for their safe handling [...]