bluuebunny/crossref_metadata_2025 huggingface dataset:
Establishment of Replication Deficient Vesicular Stomatitis Virus for Studies of PEDV Spike-Mediated Cell Entry and Its Inhibition
Authors: Luo Huaye , Lv Lilei , Yi Jingxuan , Zhou Yanjun , Liu Changlong
Published: August 2023

The porcine epidemic diarrhea virus (PEDV) is a highly contagious and virulent enteric coronavirus that causes severe enteric disease in pigs worldwide. PEDV infection causes profound diarrhea, vomiting, and dehydration in pigs of all ages, resulting in high mortality rates, particularly among neonatal piglets. The spike glycoprotein (S) of PEDV plays a crucial role in binding to the host cell receptor and facilitating fusion between the viral and host membranes. Pseudotyped viral particles featuring the PEDV S protein are valuable tools for investigating virus entry, identifying neutralizing antibodies, and developing small molecules to impede virus replication. In this study, we used a codon-optimized PEDV S protein to generate recombinant pseudotyped vesicular stomatitis virus (VSV) particles (rVSV-ΔG-EGFP-S). The full-length S protein was efficiently incorporated into VSV particles. The S protein pseudotyped VSV exhibited infectivity towards permissive cell lines of PEDV. Moreover, we identified a new permissive cell line, JHH7, which showed robust support for PEDV replication. In contrast to the SARS-CoV-2 spike protein, the removal of amino acids from the cytoplasmic tail resulted in reduced efficiency of viral pseudotyping. Furthermore, we demonstrated that 25-hydroxycholesterol inhibited rVSV-ΔG-EGFP-S entry, while human APN facilitated rVSV-ΔG-EGFP-S entry through the use of ANPEP knockout Huh7 cells. Finally, by transducing swine intestinal organoids with the rVSV-ΔG-EGFP-S virus, we observed efficient infection of the swine intestinal organoids by the PEDV spike-pseudotyped VSV. Our work offers valuable tools for studying the cellular entry of PEDV and developing interventions to curb its transmission.
Biosynthetic Pathways and Functions of Indole-3-Acetic Acid in Microorganisms
Authors: Tang Jintian , Li Yukang , Zhang Leilei , Mu Jintao , Jiang Yangyang , Fu Huilan , Zhang Yafen , Cui Haifeng , Yu Xiaoping , Ye Zihong
Published: August 2023

Indole-3-acetic acid (IAA) belongs to the family of auxin indole derivatives. IAA regulates almost all aspects of plant growth and development, and is one of the most important plant hormones. In microorganisms too, IAA plays an important role in growth, development, and even plant interaction. Therefore, mechanism studies on the biosynthesis and functions of IAA in microorganisms can promote the production and utilization of IAA in agriculture. This mini-review mainly summarizes the biosynthesis pathways that have been reported in microorganisms, including the indole-3-acetamide pathway, indole-3-pyruvate pathway, tryptamine pathway, indole-3-acetonitrile pathway, tryptophan side chain oxidase pathway, and non-tryptophan dependent pathway. Some pathways interact with each other through common key genes to constitute a network of IAA biosynthesis. In addition, functional studies of IAA in microorganisms, divided into three categories, have also been summarized: the effects on microorganisms, the virulence on plants, and the beneficial impacts on plants.
Detection of Anti-Rift Valley Fever Virus Antibodies in Serum Samples of Patients with Suspected Arbovirus Infection
Authors: Lapa Daniele , Specchiarello Eliana , Francalancia Massimo , Girardi Enrico , Maggi Fabrizio , Garbuglia Anna Rosa
Published: August 2023

The definitive diagnosis of the Rift Valley fever virus (RVFV) requires a form of testing that is available only in reference laboratories. It includes indirect immunofluorescence assay (IFA), the serum neutralization assay (NA), and real-time PCR. Therefore, often, no attempts are made to detect it, even among travelers from endemic areas. In this study, the presence of anti-RVFV IgG and IgM was retrospectively screened in stored serum samples from people who were admitted with arbovirus symptoms at the National Institute for Infectious Diseases (INMI) L. Spallanzani, Rome, Italy. Overall, 80 residual serum samples were anonymized, and sub-aliquots were prepared and tested for anti-RVFV IgG and IgM. A serum neutralization assay was used as a confirmatory test. There was a positive result in eight out of 80 samples (10%) for anti-RVFV IgG, with titers ranging from 1:40 up to 1:1280. Three of eight (2.6%) samples were confirmed as seropositive through an in-house serum neutralization assay, with antibody titers ranging from 1:10 to 1:160. All samples resulted negative for anti-RVFV IgM and RVFV RNA when tested by IFA and real-time RT-PCR, respectively. Our data highlight that several RVFV infections can possibly escape routine virological diagnosis, which suggests RVFV testing should be set up in order to monitor virus prevalence.
Photothermal/Photoacoustic Therapy Combined with Metal-Based Nanomaterials for the Treatment of Microbial Infections
Authors: Mammari Nour , Duval Raphaël E.
Published: August 2023

The increased spread and persistence of bacterial drug-resistant phenotypes remains a public health concern and has contributed significantly to the challenge of combating antibiotic resistance. Nanotechnology is considered an encouraging strategy in the fight against antibiotic-resistant bacterial infections; this new strategy should improve therapeutic efficacy and minimize side effects. Evidence has shown that various nanomaterials with antibacterial performance, such as metal-based nanoparticles (i.e., silver, gold, copper, and zinc oxide) have intrinsic antibacterial properties. These antibacterial agents, such as those made of metal oxides, carbon nanomaterials, and polymers, have been used not only to improve antibacterial efficacy but also to reduce bacterial drug resistance due to their interaction with bacteria and their photophysical properties. These nanostructures have been used as effective agents for photothermal therapy (PTT) and photodynamic therapy (PDT) to kill bacteria locally by heating or the controlled production of reactive oxygen species. Additionally, PTT or PDT therapies have also been combined with photoacoustic (PA) imaging to simultaneously improve treatment efficacy, safety, and accuracy. In this present review, we present, on the one hand, a summary of research highlighting the use of PTT-sensitive metallic nanomaterials for the treatment of bacterial and fungal infections, and, on the other hand, an overview of studies showing the PA-mediated theranostic functionality of metal-based nanomaterials.
Structural and Chemical Diversity and Complexity of Sulfur Minerals
Authors: Krivovichev Vladimir G. , Krivovichev Sergey V. , Starova Galina L.
Published: August 2023

The chemical and structural diversity of minerals containing sulfur as an essential mineral-forming element has been analyzed in terms of the concept of mineral systems and the information-based structural and chemical complexity parameters. The study employs data for 1118 sulfur mineral species approved by the International Mineralogical Association. All known sulfur minerals belong to nine mineral systems, with the number of essential components ranging from one to nine. The chemical and structural complexity of S minerals correlate with each other; that is, on average, chemical complexification results in structural complexification. The minerals with S–O bonds (sulfates and sulfites) are more complex than those without S–O bonds (sulfides and sulfosalts). However, the most complex sulfur mineral known so far is incomsartorite, Tl6Pb144As246S516, a sulfosalt. The complexity-generating mechanism in sulfides and sulfosalts is the complex combination of different modules excised from parent PbS or SnS archetypes with the subsequent formation of superstructures. The drivers for structural complexity in sulfates are more diverse and, in addition to modular construction and superstructures, also include a high hydration state, the presence of polyatomic clusters, and framework complexity. The most complex Martian minerals are most probably halotrichite-group minerals. The chemical and structural complexity increases with the passage of geological time with the formation of the most complex sulfosalts at Lengenbach (Swiss Alps) triggered by life (activity of sulfur-reducing bacteria).
Study on Electrochemical Behavior of Oxidized Pyrite in Alkaline Electrolyte
Authors: Huang Yehao , Jia Zipei , Wang Wen , Yao Jia , Gao Runbo , Xu Laifu , Zhang Hongtao , Zhang Yongsheng , Song Xiangyu
Published: August 2023

Nowadays, refractory gold ore production around the world accounts for about 30% of total gold production, and the low leaching rate of such gold concentrate seriously limits the efficient utilization of gold resources. The alkaline preoxidation process can improve the leaching rate of this kind of gold deposit and has good development and application prospects. Therefore, it is of great significance to study the oxidation and dissolution behavior of pyrite in an alkaline environment. In this paper, the oxidation process of gold-bearing pyrite in an alkaline electrolyte was studied using electrochemical techniques, and the oxidation products of a pyrite electrode in an alkaline solution were characterized using XPS, SEM, and other analytical methods. The results show that the optimum pH for pyrite electrochemical oxidative dissolution is about 12, and the oxidation potential of pyrite should be above 0.8 V. In the process of alkaline oxidative dissolution of pyrite, part of the S element enters the electrolyte in the forms of Sx2−, S2O32−, SO32−, and SO42−, and a small amount of the S element is adsorbed on the surface of the electrode in the form of S0 and becomes a part of the passive layer. The Fe element is adsorbed on the surface of the electrode in the forms of Fe(OH)2, Fe2O3, and Fe2(SO4)3, which become the main components of the passivation layer. This study provides a theoretical basis and reference data for the chemical preoxidation treatment of gold-bearing sulfide ores.
Comparative Study of Random Forest and Support Vector Machine Algorithms in Mineral Prospectivity Mapping with Limited Training Data
Authors: Lachaud Alix , Adam Marcus , Mišković Ilija
Published: August 2023

This paper employs two data-driven methods, Random Forest (RF) and Support Vector Machines (SVM), to develop mineral prospectivity models for an epithermal Au deposit. Four distinct models are presented for comparison: one employing RF and three using SVM with different kernel functions—namely linear, Radial Basis Function (RBF), and polynomial. The analysis leverages a compact training dataset, encompassing just 20 deposits, with deposit and non-deposit locations chosen from known mineral occurrences. Fourteen predictor maps are constructed based on the available data and the exploration model. The findings indicate that RF is more stable and robust than SVM, regardless of the kernel function implemented. While all SVM models outperformed the RF model in terms of classification capability on the training dataset achieving an accuracy exceeding 89% versus 78% for the RF model, the success rate curves suggest superior predictive abilities of RF over SVM models. This implies that the SVM models may be overfitting the training data due to the limited quantity of training deposits.
Two-Stage Evolution of the Altyn Tagh Fault System during the Tertiary: Constraints from Heavy Mineral Chemistry in Sediments of the Northwestern Qaidam Basin, Western China
Authors: Bai Lu , Fu Ling , Guan Ping , Zhang Daowei
Published: August 2023

The tectonic evolution of the Altyn Tagh Fault (ATF) remains controversial during the Tertiary. Qaidam Basin is the largest and highest plateau inland basin inside the Tibet Plateau. Sediments in the basin provide sedimentary records of the evolution history of its surrounding orogens, such as the ATF, located on the northwest margin of the Qaidam Basin. Comprehensive analyses of sandstone petrography, heavy mineral assemblages, and mineral geochemistry were adopted to effectively indicate the tectonic evolution history of ATF. The result indicates that the sediments in a wide range of the northwestern Qaidam Basin (e.g., the Xichagou section, the Yueyashan section) were derived from the Altyn Mountains. The increasing immaturity of sediments, increased denudation, and sedimentation processes from the early-middle Miocene to the Pliocene can be explained by the active tectonic setting of the ATF. During the early Miocene (ca. 22 Ma), there was an abrupt change in the heavy mineral composition of sediments in the northwestern Qaidam Basin. This change may be attributed to the large-scale slip motion along the ATF. Therefore, ~22 Ma is the key transforming period of the ATF system. On the foundation of the above, we suggest a two-stage evolution model of the ATF during the Tertiary: (1) From the late Eocene to the Oligocene, the tectonic setting of the ATF was relatively calm; (2) During the early Miocene period, the ATF underwent large-scale tectonic activation. It is likely to be a strike-slip tectonic activity, accompanied by an uplift of the Altyn Mountains. The active tectonic setting of the ATF was sustained after the Miocene.
Experimental Study on Dense Settlement of Full-Tail Mortar under Mechanical Vibration
Authors: Lai Wei , Zhou Keping , Gao Feng , Pan Zheng , Gao Xiu
Published: August 2023

There are some problems in the application of slurry preparation technology, such as wide fluctuation range of underflow concentration, long settling time and low efficiency of solid–liquid separation. This is an important basis for researching the thick settling law of tailings slurry under the action of mechanical vibration and its influencing factors to solve these problems. To this end, a small vibration thickening testing machine and vibrating rod were designed and developed. Physical simulation experiments were conducted to analyze the settling characteristics of tailings slurry under different vibration duration, start time, vibration frequency, and vibration inertia single factors. The results show that: (1) Mechanical vibration can effectively accelerate the settling speed of tailings particles, but the relationship between them is a non-positive correlation, and mechanical vibration time control with in 5 mins is the best. With the delay of starting the vibration time, the final mass concentration first increases and then decreases. (2) As the vibration frequency increases, the final mass concentration of tailings settlement first increases and then decreases. When the eccentric vibrator speed is 6000 r/min, the best slurry settlement effect is achieved. (3) When the vibration inertia of the eccentric oscillator is 0.158 g·cm2 and the final mass concentration reaches 70.1%, the settling time only takes 210 min. (4) The lower the slurry concentration, the faster the settling speed. As the initial concentration increases, the final thickening time is also gradually prolonged. The research results provide some insights for the rapid thickening technology of rake-free paste thickeners.
Determination of the CO2 Uptake of Construction Products Manufactured by Mineral Carbonation
Authors: Nielsen Peter , Quaghebeur Mieke
Published: August 2023

Mineral carbonation is a technology for capturing and storing CO2 in solid minerals. When mineral carbonation is used to produce construction materials, the quantification of the CO2 uptake of these products is of the utmost importance, as it is used to calculate the CO2 footprint of the product and/or carbon offset. The CO2 uptake is generally determined by measuring the CO2 content of a material before and after accelerated carbonation. This approach, however, does not take hydration and dehydroxylation reactions into account that may occur during carbonation, and it can therefore under- or overestimate the CO2 uptake. Thus, a more accurate and practical method to determine CO2 uptake, which also accounts for hydration and dehydroxylation reactions, is proposed in this paper. This method is based on analytical methods to determine the dry mass and the CO2 content of the solid products before and after carbonation, and on the calculation of the CO2 uptake by the following equation: CO2 uptake (wt.%) = CO2 carbonated (wt.%) × (weight after carbonation (g)/weight before carbonation (g) − CO2 initial (wt.%), with CO2 carbonated being the CO2 content in g/100 g dried carbonated material, and CO2 initial being the CO2 content in g/100 g dried initial material, i.e., before carbonation. The “weight before carbonation” is the dry weight of the initial material, and the “weight after carbonation” is the product’s dry weight after carbonation. In this paper, we show that up to 44% under- or overestimation of CO2 uptake can occur when hydration and dehydroxylation reactions are not taken into account during mineral carbonation.
Genesis and Formation of the Tuwaishan Gold Deposit in Hainan Island, South China: Implications from H-O-S Isotopes
Authors: Liu Yuheng , Mao Jingwen , Hu Jun , Wang Lei , Xu Deming
Published: August 2023

The Tuwaishan gold deposit is located at the northeastern end of the Gezhen shear zone in the western part of Hainan Island, South China. It is one of a series of similar gold deposits hosted in the Mesoproterozoic basement rocks and structurally controlled by the Gezhen shear zone. The hydrothermal ore-forming period can be divided into quartz-pyrite-arsenopyrite stage, quartz-pyrite-base metal sulfides stage and quartz-carbonate stage. Eleven gold-bearing quartz vein samples yield δDV-SMOW and δ18OV-SMOW values of −75.9‰ to −54.4‰ and +8.1‰ to +13.7‰, respectively, and the corresponding δ18Owater values range from +3.1‰ to +8.7‰. In addition, the pyrite separates from 14 ore samples yield δ34S values of +4.5‰ to +7.9‰. The H-O-S isotopic data, along with fluid properties of the Tuwaishan and other gold deposits along the Gezhen shear zone, suggest that the ore-forming fluid and materials are of metamorphic rather than magmatic origin. Hence, we propose that the Tuwaishan gold deposit is best classified as orogenic gold deposit that resulted from regional metamorphism. Considering that the Mesoproterozoic basement rocks have experienced amphibolite facies metamorphism prior to the gold mineralization, the metamorphic devolatilization of the Ordovician-Silurian rocks at depth would provide a realistic source of fluid, gold and sulfur for the Tuwaishan and other gold deposits of the Gezhen gold belt.
The Fontanamare Discovery (Sardinia Coast, Italy), a Case of Underwater Corrosion of Bronze Coins
Authors: de Caro Tilde , Susanna Fiammetta , La Russa Mauro Francesco , Macchia Andrea
Published: August 2023

This study reports the analytical approach towards nine coins found in wreck A of Fontanamare for understanding the complex corrosion processes that take place in underwater conditions. Optical microscopy (OM) combined with micro-Raman (µ-Raman) spectroscopy, X-ray diffractometry (XRD), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM and EDS) were used to analyze the nature and the microstructure of the corrosion patina in comparison with the non-degraded state of coins. Three main types of corrosion patina based on copper, lead chloride, and carbonate were identified: black, white, and green, and the obtained results demonstrate the complex corrosion processes that take place in underwater conditions. To better understand the role played by different chemical and physical parameters in the corrosion of bronze artefacts in an underwater environment, this study attempts to understand the nature of the patinas on the coins in relation to the specific structural and environmental parameter variation.
Characterization of Bioactivity of Selective Molecules in Fruit Wines by FTIR and NMR Spectroscopies, Fluorescence and Docking Calculations
Authors: Kim Young-Mo , Lubinska-Szczygeł Martyna , Park Yong-Seo , Deutsch Joseph , Ezra Aviva , Luksrikul Patraporn , Beema Shafreen Raja Mohamed , Gorinstein Shela
Published: August 2023

Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies were applied to characterize and compare the chemical shifts in the polyphenols’ regions of some fruit wines. The obtained results showed that FTIR spectra (1800–900 cm−1) and 1H NMR (δ 6.5–9.3 ppm) of different fruit wines can be used as main indices of the year of vintage and quality of fruit wines. In addition to the classical determination of antioxidant profiles and bioactive substances in wines, fluorometric measurements were used to determine the interactions of wine substances with the main human serum proteins. The results showed relatively high binding properties of wines with the highest one for pomegranate, followed by kiwifruit and persimmon wines. The interactions of vitamin C, catechin and gallic acid with human serum albumin (HSA) were also examined by docking studies. The docking calculations showed that gallic acid has a stronger binding affinity compared to catechin and vitamin C. The stronger binding affinity of gallic acid may be due to three hydrogen bonds and pi–pi interactions. The fluorescence and docking studies proved that only the bioactive compounds of wines and not the amount of alcohol have high binding properties to human serum proteins. The emphasis in this report was made on the utility of FTIR, NMR and fluorescence of wines as a mean of wine authentication and its fingerprint. The findings, based on polyphenols from fruits and fruit wines, their bioactivity and health properties, offer valuable insights for future endeavours focused on designing healthy food products.
A Study of the Bisphosphonic Derivatives from the Pudovik Reaction of Dialkyl α-Oxophosphonates and >P(O)H Reagents: X-ray Structure and Bioactivity
Authors: Szalai Zsuzsanna , Tóth Boldizsár , Szabó Rita Oláhné , Bősze Szilvia , Karaghiosoff Konstantin , Czugler Mátyás , Drahos László , Keglevich György
Published: August 2023

New hydroxy-methylenebisphosphonic derivatives were prepared with different P-functions. The outcome of the reaction of α-oxophosphonates (YC(O)P(O)(OR)2) and dialkyl phosphites or diarylphosphine oxides depended on the Y substituent of the oxo-compound, the nature of the P-reagent and the amount of the diethylamine catalyst. Starting from dimethyl α-oxoethylphosphonate, in the presence of 5% of diethylamine, the corresponding Pudovik adduct was the single product. While using 40% of the catalyst, the rearranged species with the >P(O)–O–CH–P(O)< skeleton was the exclusive component. A similar reaction of α-oxobenzylphosphonate followed the rearrangement protocol. X-ray crystallography revealed not only the spatial structures of the three products, but also an intricate pattern evolving from the interplay of slight chemical differences, solvent inclusion and disorder as well as H-bridge patterns, which invite further investigation. In vitro activity of the compounds was assessed on different tumor cell cultures using end-point-type cell tetrazolium-based measurements. These structure–activity studies revealed a cytostatic effect for four rearranged derivatives containing aromatic units. One of them had a pronounced effect on MDA-MB 231 and Ebc-1 cells, showing IC50 = 37.8 and 25.9 µM, respectively.
Analytical and Clinical Validation of Assays for Volumetric Absorptive Microsampling (VAMS) of Drugs in Different Blood Matrices: A Literature Review
Authors: Nugraha Rhea Veda , Yunivita Vycke , Santoso Prayudi , Hasanah Aliya Nur , Aarnoutse Rob E. , Ruslami Rovina
Published: August 2023

Volumetric absorptive microsampling (VAMS) is the newest and most promising sample-collection technique for quantitatively analyzing drugs, especially for routine therapeutic drug monitoring (TDM) and pharmacokinetic studies. This technique uses an absorbent white tip to absorb a fixed volume of a sample (10–50 µL) within a few seconds (2–4 s), is more flexible, practical, and more straightforward to be applied in the field, and is probably more cost-effective than conventional venous sampling (CVS). After optimization and validation of an analytical method of a drug taken by VAMS, a clinical validation study is needed to show that the results by VAMS can substitute what is gained from CVS and to justify implementation in routine practice. This narrative review aimed to assess and present studies about optimization and analytical validation of assays for drugs taken by VAMS, considering their physicochemical drug properties, extraction conditions, validation results, and studies on clinical validation of VAMS compared to CVS. The review revealed that the bio-analysis of many drugs taken with the VAMS technique was optimized and validated. However, only a few clinical validation studies have been performed so far. All drugs that underwent a clinical validation study demonstrated good agreement between the two techniques (VAMS and CVS), but only by Bland–Altman analysis. Only for tacrolimus and mycophenolic acid were three measurements of agreement evaluated. Therefore, VAMS can be considered an alternative to CVS in routine practice, especially for tacrolimus and mycophenolic acid. Still, more extensive clinical validation studies need to be performed for other drugs.
Xanthones with Potential Anti-Inflammatory and Anti-HIV Effects from the Stems and Leaves of Cratoxylum cochinchinense
Authors: Zhang Yong , Guo Jia-Ming , Zhang Ming-Ming , Wang Ran , Liang Chai-Huan , Zhao Yi-Meng , Deng Ya-Yuan , Liu Yan-Ping , Fu Yan-Hui
Published: August 2023

Four new xanthones, cratocochinones A–D (1–4), together with eight known analogues (5–12), were isolated from the stems and leaves of Cratoxylum cochinchinense. The chemical structures of cratocochinones A–D (1–4) were elucidated by comprehensive spectroscopic analyses and the known compounds were identified by comparisons with the spectral data reported in the literature. All isolated compounds 1–12 were evaluated for their anti-inflammatory activities and anti-HIV-1 activities. Compounds 1–12 showed remarkable inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro, with IC50 values in the range of 0.86 ± 0.05 to 18.36 ± 0.21 µM. Meanwhile, compounds 1–12 exhibited significant anti-HIV-1 activities with EC50 which ranged from 0.22 to 11.23 µM. These findings indicate that the discoveries of these xanthones, isolated from the stems and leaves of C. cochinchinense, showing significant anti-inflammatory and anti-HIV-1 effects could be of great importance to the research and development of new natural anti-inflammatory and anti-HIV agents.
Detection of Mildewed Nutmeg Internal Quality during Storage Using an Electronic Nose Combined with Chemical Profile Analysis
Authors: Cui Yang , Yao Yuebao , Yang Ruiqi , Wang Yashun , Liang Jingni , Ouyang Shaoqin , Yu Shulin , Zou Huiqin , Yan Yonghong
Published: August 2023

Internal mildewed nutmeg is difficult to perceive without cutting the nutmeg open and examining it carefully, which poses a significant risk to public health. At present, macroscopic identification and chromatographic analysis are applied to determine whether nutmeg is moldy or not. However, the former relies on a human panel, with the disadvantages of subjectivity and empirical dependence, whilst the latter is generally time-consuming and requires organic solvents. Therefore, it is urgent to develop a rapid and feasible approach for evaluating the quality and predicting mildew in nutmeg. In this study, the quality and odor characteristics of five groups of nutmeg samples with different degrees of mildew were analyzed by using the responses of an electronic nose combined with chemical profiling. The main physicochemical indicators, such as the levels of α-pinene, β-pinene, elemicin, and dehydro-di-isoeugenol, were determined. The results revealed that the contents of α-pinene, β-pinene, and elemicin changed significantly with the extension of storage time. Through the use of an electronic nose and HS–GC–MS technology to assess the overall odor characteristics of nutmeg samples, it was found that the production of volatile organic compounds (VOCs) such as ammonia/organic amines, carbon monoxide, ethanol, and hydrogen sulfide, as well as changes in the terpene and phenylpropene components of the nutmeg itself, may be the material basis for the changes in odor. The accuracy of the qualitative classification model for the degree of mildew in nutmeg was higher than 90% according to the electronic nose data combined with different machine learning algorithms. Quantitative models were established for predicting the contents of the chemical components, and models based on a BP neural network (BPNN), the support vector machine (SVM), and the random forest algorithm (RF) all showed good performance in predicting the concentrations of these chemical components, except for dehydro-di-isoeugenol. The BPNN performed effectively in predicting the storage time of nutmeg on the basis of the E-nose’s responses, with an RMSE and R2 of 0.268 and 0.996 for the training set, and 0.317 and 0.993 for the testing set, respectively. The results demonstrated that the responses of the electronic nose (E-nose) had a high correlation with the internal quality of nutmeg. This work proposes a quick and non-destructive evaluation method for the quality of nutmeg, which has high accuracy in discriminating between different degrees of mold in nutmeg and is conducive to early detection and warning of moldy phenomena.
Structure Activity Relationship and Molecular Docking of Some Quinazolines Bearing Sulfamerazine Moiety as New 3CLpro, cPLA2, sPLA2 Inhibitors
Authors: Hussein Mohammed Abdalla , Borik Rita M. , Nafie Mohamed S. , Abo-Salem Heba M. , Boshra Sylvia A. , Mohamed Zahraa N.
Published: August 2023

The current work was conducted to synthesize several novel anti-inflammatory quinazolines having sulfamerazine moieties as new 3CLpro, cPLA2, and sPLA2 inhibitors. The thioureido derivative 3 was formed when compound 2 was treated with sulfamerazine. Also, compound 3 was reacted with NH2-NH2 in ethanol to produce the N-aminoquinazoline derivative. Additionally, derivative 4 was reacted with 4-hydroxy-3-methoxybenzaldehyde, ethyl chloroacetate, and/or diethyl oxalate to produce quinazoline derivatives 5, 6, and 12, respectively. The results of the pharmacological study indicated that the synthesized 4–6 and 12 derivatives showed good 3CLpro, cPLA2, and sPLA2 inhibitory activity. The IC50 values of the target compounds 4–6, and 12 against the SARS-CoV-2 main protease were 2.012, 3.68, 1.18, and 5.47 µM, respectively, whereas those of baicalein and ivermectin were 1.72 and 42.39 µM, respectively. The IC50 values of the target compounds 4–6, and 12 against sPLA2 were 2.84, 2.73, 1.016, and 4.45 µM, respectively, whereas those of baicalein and ivermectin were 0.89 and 109.6 µM, respectively. The IC50 values of the target compounds 4–6, and 12 against cPLA2 were 1.44, 2.08, 0.5, and 2.39 µM, respectively, whereas those of baicalein and ivermectin were 3.88 and 138.0 µM, respectively. Also, incubation of lung cells with LPS plus derivatives 4–6, and 12 caused a significant decrease in levels of sPLA2, cPLA2, IL-8, TNF-α, and NO. The inhibitory activity of the synthesized compounds was more pronounced compared to baicalein and ivermectin. In contrast to ivermectin and baicalein, bioinformatics investigations were carried out to establish the possible binding interactions between the newly synthesized compounds 2–6 and 12 and the active site of 3CLpro. Docking simulations were utilized to identify the binding affinity and binding mode of compounds 2–6 and 12 with the active sites of 3CLpro, sPLA2, and cPLA2 enzymes. Our findings demonstrated that all compounds had outstanding binding affinities, especially with the key amino acids of the target enzymes. These findings imply that compound 6 is a potential lead for the development of more effective SARS-CoV-2 Mpro inhibitors and anti-COVID-19 quinazoline derivative-based drugs. Compound 6 was shown to have more antiviral activity than baicalein and against 3CLpro. Furthermore, the IC50 value of ivermectin against the SARS-CoV-2 main protease was revealed to be 42.39 µM, indicating that it has low effectiveness.
Regulating Al2O3/PAN/PEG Nanofiber Membranes with Suitable Phase Change Thermoregulation Features
Authors: Huang Leping , Chen Ying , Xu Zhaobao , He Cui , Li Youmu , Zhao Jinchao , Tang Youhong
Published: August 2023

To address the thermal comfort needs of the human body, the development of personal thermal management textile is critical. Phase change materials (PCMs) have a wide range of applications in thermal management due to their large thermal storage capacity and their isothermal properties during phase change. However, their inherent low thermal conductivity and susceptibility to leakage severely limit their application range. In this study, polyethylene glycol (PEG) was used as the PCM and polyacrylonitrile (PAN) as the polymer backbone, and the thermal conductivity was increased by adding spherical nano-alumina (Al2O3). Utilizing coaxial electrospinning technology, phase-change thermoregulated nanofiber membranes with a core-shell structure were created. The study demonstrates that the membranes perform best in terms of thermal responsiveness and thermoregulation when 5% Al2O3 is added. The prepared nanofiber membranes have a melting enthalpy of 60.05 J·g−1 and retain a high enthalpy after 50 cycles of cold and heat, thus withstanding sudden changes in ambient temperature well. Additionally, the nanofiber membranes have excellent air permeability and high moisture permeability, which can increase wearer comfort. As a result, the constructed coaxial phase change thermoregulated nanofiber membranes can be used as a promising textile for personal thermal management.
Optimizing the Performance of Low-Loaded Electrodes for CO2-to-CO Conversion Directly from Capture Medium: A Comprehensive Parameter Analysis
Authors: Mezza Alessio , Bartoli Mattia , Chiodoni Angelica , Zeng Juqin , Pirri Candido F. , Sacco Adriano
Published: August 2023

Gas-fed reactors for CO2 reduction processes are a solid technology to mitigate CO2 accumulation in the atmosphere. However, since it is necessary to feed them with a pure CO2 stream, a highly energy-demanding process is required to separate CO2 from the flue gasses. Recently introduced bicarbonate zero-gap flow reactors are a valid solution to integrate carbon capture and valorization, with them being able to convert the CO2 capture medium (i.e., the bicarbonate solution) into added-value chemicals, such as CO, thus avoiding this expensive separation process. We report here a study on the influence of the electrode structure on the performance of a bicarbonate reactor in terms of Faradaic efficiency, activity, and CO2 utilization. In particular, the effect of catalyst mass loading and electrode permeability on bicarbonate electrolysis was investigated by exploiting three commercial carbon supports, and the results obtained were deepened via electrochemical impedance spectroscopy, which is introduced for the first time in the field of bicarbonate electrolyzers. As an outcome of the study, a novel low-loaded silver-based electrode fabricated via the sputtering deposition technique is proposed. The silver mass loading was optimized by increasing it from 116 μg/cm2 to 565 μg/cm2, thereby obtaining an important enhancement in selectivity (from 55% to 77%) and activity, while a further rise to 1.13 mg/cm2 did not provide significant improvements. The tremendous effect of the electrode permeability on activity and proficiency in releasing CO2 from the bicarbonate solution was shown. Hence, an increase in electrode permeability doubled the activity and boosted the production of in situ CO2 by 40%. The optimized Ag-electrode provided Faradaic efficiencies for CO close to 80% at a cell voltage of 3 V and under ambient conditions, with silver loading of 565 μg/cm2, the lowest value ever reported in the literature so far.
A Sensitive Micro Conductometric Ethanol Sensor Based on an Alcohol Dehydrogenase-Gold Nanoparticle Chitosan Composite
Authors: Madaci Anis , Suwannin Patcharapan , Raffin Guy , Hangouet Marie , Martin Marie , Ferkous Hana , Bouzid Abderrazak , Bausells Joan , Elaissari Abdelhamid , Errachid Abdelhamid , Jaffrezic-Renault Nicole
Published: August 2023

In this paper, a microconductometric sensor has been designed, based on a chitosan composite including alcohol dehydrogenase—and its cofactor—and gold nanoparticles, and was calibrated by differential measurements in the headspace of aqueous solutions of ethanol. The role of gold nanoparticles (GNPs) was crucial in improving the analytical performance of the ethanol sensor in terms of response time, sensitivity, selectivity, and reproducibility. The response time was reduced to 10 s, compared to 21 s without GNPs. The sensitivity was 416 µS/cm (v/v%)−1 which is 11.3 times higher than without GNPs. The selectivity factor versus methanol was 8.3, three times higher than without GNPs. The relative standard deviation (RSD) obtained with the same sensor was 2%, whereas it was found to be 12% without GNPs. When the air from the operator’s mouth was analyzed just after rinsing with an antiseptic mouthwash, the ethanol content was very high (3.5 v/v%). The background level was reached only after rinsing with water.
Enhanced Thermal Conductivity and Dielectric Properties of Epoxy Composites with Fluorinated Graphene Nanofillers
Authors: Zhang Jiacheng , Wang Zi , Jiang Guoqing , Wei Huachao , Zhang Zongxi , Ren Junwen
Published: August 2023

The demand for high-performance dielectrics has increased due to the rapid development of modern electric power and electronic technology. Composite dielectrics, which can overcome the limitations of traditional single polymers in thermal conductivity, dielectric properties and mechanical performance, have received considerable attention. In this study, we report a multifunctional nanocomposite material fabricated by blending fluorinated graphene (F-graphene) with epoxy resin. The F-graphene/epoxy composite exhibited a high thermal conductivity of 0.3304 W·m−1·K−1 at a low filler loading of 1.0 wt.%, which was 67.63% higher than that of pure epoxy. The composite dielectric also showed high breakdown strength (78.60 kV/mm), high dielectric constant (8.23), low dielectric loss (<0.015) and low AC conductivity (<10−11 S·m−1). Moreover, the composite demonstrated high thermal stability and strong mechanical strength. It is believed that the F-graphene/epoxy composite has outstanding performance in various aspects and can enable the development and manufacturing of advanced electric power and electronic equipment devices.
Competitive Growth of Ge Quantum Dots on a Si Micropillar with Pits for a Precisely Site-Controlled QDs/Microdisk System
Authors: Yan Jia , Zhang Zhifang , Zhang Ningning , Huang Qiang , Zhan Yan , Jiang Zuimin , Zhong Zhenyang
Published: August 2023

Semiconductor quantum dots (QDs)/microdisks promise a unique system for comprehensive studies on cavity quantum electrodynamics and great potential for on-chip integrated light sources. Here, we report on a strategy for precisely site-controlled Ge QDs in SiGe microdisks via self-assembly growth of QDs on a micropillar with deterministic pits and subsequent etching. The competitive growth of QDs in pits and at the periphery of the micropillar is disclosed. By adjusting the growth temperature and Ge deposition, as well as the pit profiles, QDs can exclusively grow in pits that are exactly located at the field antinodes of the corresponding cavity mode of the microdisk. The inherent mechanism of the mandatory addressability of QDs is revealed in terms of growth kinetics based on the non-uniform surface chemical potential around the top of the micropillar with pits. Our results demonstrate a promising approach to scalable and deterministic QDs/microdisks with strong light–matter interaction desired for fundamental research and technological applications.
Tailoring the Magnetic and Electrical Properties of Epoxy Composites Containing Olive-Derived Biochar through Iron Modification
Authors: Piatti Erik , Torsello Daniele , Gavello Gaia , Ghigo Gianluca , Gerbaldo Roberto , Bartoli Mattia , Duraccio Donatella
Published: August 2023

The combination of conductive carbon together with magnetic particles is a consolidated strategy to produce cutting-edge fillers for the production of polymer composites able to shield against microwave radiation. In this work, we developed and characterized an iron-tailored biochar obtained from the pyrolysis of olive pruning which was added as filler for the preparation of epoxy composites. The biochar-based composites were obtained by keeping the filler concentration at 10 and 40 wt.%. An extensive characterization was carried out in order to assess the electrical and magnetic properties of the composites containing biochar and iron-tailored biochar. The highest DC electrical conductivity of 59 mS/m was observed in the 40 wt.% iron-tailored biochar-loaded composite, while the reduction of the filler loading led to a drastic reduction in conductivity: 60 μS/m in the 10 wt.%-loaded composite. Ferromagnetic behavior of composites containing iron-tailored biochar is visible in the emerging hysteretic behavior, with a magnetic signal increasing with the filler concentration. Finally, both the complex permittivity (ε’) and the AC conductivity (σ) are enhanced by increasing the BC filler amount in the matrix, regardless of the presence of iron.
Formation of Multiscale Pattern Structures by Combined Patterning of Nanotransfer Printing and Laser Micromachining
Authors: Park Tae Wan , Kang Young Lim , Kang Eun Bin , Kim Seungmin , Kim Yu Na , Park Woon Ik
Published: August 2023

Various lithography techniques have been widely used for the fabrication of next-generation device applications. Micro/nanoscale pattern structures formed by lithographic methods significantly improve the performance capabilities of the devices. Here, we introduce a novel method that combines the patterning of nanotransfer printing (nTP) and laser micromachining to fabricate multiscale pattern structures on a wide range of scales. Prior to the formation of various nano-in-micro-in-millimeter (NMM) patterns, the nTP process is employed to obtain periodic nanoscale patterns on the target substrates. Then, an optimum laser-based patterning that effectively engraves various nanopatterned surfaces, in this case, spin-cast soft polymer film, rigid polymer film, a stainless still plate, and a Si substrate, is established. We demonstrate the formation of well-defined square and dot-shaped multiscale NMM-patterned structures by the combined patterning method of nTP and laser processes. Furthermore, we present the generation of unusual text-shaped NMM pattern structures on colorless polyimide (CPI) film, showing optically excellent rainbow luminescence based on the configuration of multiscale patterns from nanoscale to milliscale. We expect that this combined patterning strategy will be extendable to other nano-to-micro fabrication processes for application to various nano/microdevices with complex multiscale pattern geometries.
Self-Assembly of Copper Oxide Interfaced MnO2 for Oxygen Evolution Reaction
Authors: Bathula Chinna , Meena Abhishek , Sekar Sankar , Singh Aditya Narayan , Soni Ritesh , El-Marghany Adel , Palem Ramasubba Reddy , Kim Hyun-Seok
Published: August 2023

Designing efficient electrocatalytic systems through facile synthesis remains a formidable task. To address this issue, this paper presents the design of a combination material comprising two transition metal oxides (copper oxide and manganese oxide (CuO/MnO2)), synthesized using a conventional microwave technique to efficiently engage as an active oxygen evolution reaction (OER) catalyst. The structural and morphological properties of the composite were confirmed by the aid of X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectrometry (EDS). FESEM clearly indicated well-aligned interlacing of CuO with MnO2. The OER performance was carried out in 1 M KOH. The assembled CuO/MnO2 delivered a benchmark current density (j = 10 mA cm−2) at a minimal overpotential (η = 294 mV), while pristine CuO required a high η (316 mV). Additionally, the CuO/MnO2 electrocatalyst exhibited stability for more than 15 h. These enhanced electrochemical performances were attributed to the large volume and expanded diameter of the pores, which offer ample surface area for catalytic reactions to boost OER. Furthermore, the rate kinetics of the OER are favored in composite due to low Tafel slope (77 mV/dec) compared to CuO (80 mV/dec).
Low-Cost Manufacturing of Monolithic Resonant Piezoelectric Devices for Energy Harvesting Using 3D Printing
Authors: Duque Marcos , Murillo Gonzalo
Published: August 2023

The rapid increase of the Internet of Things (IoT) has led to significant growth in the development of low-power sensors. However; the biggest challenge in the expansion of the IoT is the energy dependency of the sensors. A promising solution that provides power autonomy to the IoT sensor nodes is energy harvesting (EH) from ambient sources and its conversion into electricity. Through 3D printing, it is possible to create monolithic harvesters. This reduces costs as it eliminates the need for subsequent assembly tools. Thanks to computer-aided design (CAD), the harvester can be specifically adapted to the environmental conditions of the application. In this work, a piezoelectric resonant energy harvester has been designed, fabricated, and electrically characterized. Physical characterization of the piezoelectric material and the final resonator was also performed. In addition, a study and optimization of the device was carried out using finite element modeling. In terms of electrical characterization, it was determined that the device can achieve a maximum output power of 1.46 mW when operated with an optimal load impedance of 4 MΩ and subjected to an acceleration of 1 G. Finally, a proof-of-concept device was designed and fabricated with the goal of measuring the current passing through a wire.
High-Resolution Nanotransfer Printing of Porous Crossbar Array Using Patterned Metal Molds by Extreme-Pressure Imprint Lithography
Authors: Park Tae Wan , Kang Young Lim , Kim Yu Na , Park Woon Ik
Published: August 2023

High-resolution nanotransfer printing (nTP) technologies have attracted a tremendous amount of attention due to their excellent patternability, high productivity, and cost-effectiveness. However, there is still a need to develop low-cost mold manufacturing methods, because most nTP techniques generally require the use of patterned molds fabricated by high-cost lithography technology. Here, we introduce a novel nTP strategy that uses imprinted metal molds to serve as an alternative to a Si stamp in the transfer printing process. We present a method by which to fabricate rigid surface-patterned metallic molds (Zn, Al, and Ni) based on the process of direct extreme-pressure imprint lithography (EPIL). We also demonstrate the nanoscale pattern formation of functional materials, in this case Au, TiO2, and GST, onto diverse surfaces of SiO2/Si, polished metal, and slippery glass by the versatile nTP method using the imprinted metallic molds with nanopatterns. Furthermore, we show the patterning results of nanoporous crossbar arrays on colorless polyimide (CPI) by a repeated nTP process. We expect that this combined nanopatterning method of EPIL and nTP processes will be extendable to the fabrication of various nanodevices with complex circuits based on micro/nanostructures.