bluuebunny/crossref_metadata_2025 huggingface dataset:
Plasma Electrolytic Modification of Zirconium and Its Alloys: Brief Review
Authors: Krit Boris L. , Apelfeld Andrey V. , Borisov Anatoly M. , Morozova Natalia V. , Rakoch Alexander G. , Suminov Igor V. , Grigoriev Sergey N.
Published: August 2023

The review focuses on the surface modification of Zr and its alloys, which is necessary to expand the applications of these kinds of materials. Data on the properties of pure zirconium and its alloys are presented. Since surface engineering and the operation of the above materials are in most cases associated with the formation of oxide coatings, information on the characteristics of ZrO2 is given. In addition, attention is paid to phasing in the zirconium–oxygen system. It is noted that the most effective method of surface engineering of Zr and its alloys is plasma electrolytic modification (PEM) technology. Specific examples and modes of modification are described, and the reached results are analyzed. The relevance, novelty and originality of the review are determined by the insufficient knowledge about a number of practical features concerning the formation of functional oxide coatings on Zr and some of its alloys by the technology of PEM. In particular, the information on the phase composition and possibilities of stabilization of the tetragonal and cubic modifications of ZrO2, the effects of the component composition of electrolyte solutions and electrolyte suspensions, and the specifics of the treatment of additive shaping and deformed materials are rather contradictory. This review aims to collect recent advances and provide insights into the trends in the modification of Zr and its alloys, promote the formulation of practical recommendations and assess the development prospects.
Mono- and Co-Doped Mn-Doped CsPbCl3 Perovskites with Enhanced Doping Efficiency and Photoluminescent Performance
Authors: Jiang Hao , Zhao Yiting , Liu Fangchao , Yan Yongqi , Ma Yinuo , Bao Hexin , Wu Zhongchen , Cong Wei-Yan , Lu Ying-Bo
Published: August 2023

To investigate the effect of Mn and other metal dopants on the photoelectronic performance of CsPbCl3 perovskites, we conducted a series of theoretical analyses. Our findings showed that after Mn mono-doping, the CsPbCl3 lattice contracted and the bonding strength increased, resulting in a more compact structure of the metal octahedral cage. The relaxation of the metal octahedral cage, along with the Jahn–Teller effect, results in a decrease in lattice strain between the octahedra and a reduction in the energy of the entire lattice due to the deformation of the metal octahedron. These three factors work together to reduce intrinsic defects and enhance the stability and electronic properties of CsPbCl3 perovskites. The solubility of the Mn dopant is significantly increased when co-doped with Ni, Fe, and Co dopants, as it compensates for the lattice strain induced by Mn. Doping CsPbCl3 perovskites reduces the band gap due to the decreased contributions of 3d orbitals from the dopants. Our analyses have revealed that strengthening the CsPbCl3 lattice and reducing intrinsic defects can result in improved stability and PL properties. Moreover, increasing Mn solubility and decreasing the bandgap can enhance the PLQY of orange luminescence in CsPbCl3 perovskites. These findings offer valuable insights for the development of effective strategies to enhance the photoelectronic properties of these materials.
Asymmetric TMO–Metal–TMO Structure for Enhanced Efficiency and Long-Term Stability of Si-Based Heterojunction Solar Cells
Authors: Jung Yoon-Chae , Yu Young-Jin , Kim Yu-Kyung , Lee Jin Hee , Seo Jung Hwa , Choi Jea-Young
Published: August 2023

In this study, we fabricated Si-based heterojunction solar cells (HSCs) with an asymmetric TMO–metal–TMO (TMT) structure using both MoO3 and V2O5 as the hole-selective contacts. Our HSCs offer enhanced long-term stability and effective passivation for crystal defects on the Si sur-face. We analyzed the oxygen vacancy state and surface morphology of the MoO3- and V2O5-TMO thin films using X-ray photoelectron spectroscopy and atomic force microscopy to investigate their passivation characteristics for Si surface defects. From the measured minority carrier lifetime, V2O5 revealed a highly improved lifetime (590 μs) compared to that of MoO3 (122.3 μs). In addition, we evaluated the long-term stability of each TMO thin film to improve the operation stability of the HSCs. We deposited different types of TMOs as the top- and bottom-TMO layers and assessed the effect of the thickness of each TMO layer. The fabricated asymmetric TMT/Si HSCs showed noticeable improvements in efficiency (7.57%) compared to 6.29% for the conventional symmetric structure which used the same TMO material for both the top and bottom layers. Furthermore, in terms of long-term stability, the asymmetric TMT/Si HSCs demonstrated an efficiency that was 250% higher than that of symmetric TMT/Si HSCs, as determined via power conversion efficiency degradation over 2000 h which is mainly attributed by the lower oxygen vacancy of the top-TMO, V2O5. These results suggest that the asymmetric TMT structure is a promising approach for the fabrication of low-cost and high-efficiency Si-based HSCs with enhanced long-term stability.
Threat Hunting System for Protecting Critical Infrastructures Using a Machine Learning Approach
Authors: Aragonés Lozano Mario , Pérez Llopis Israel , Esteve Domingo Manuel
Published: August 2023

Cyberattacks are increasing in number and diversity in nature daily, and the tendency for them is to escalate dramatically in the forseeable future, with critical infrastructures (CI) assets and networks not being an exception to this trend. As time goes by, cyberattacks are more complex than before and unknown until they spawn, being very difficult to detect and remediate. To be reactive against those cyberattacks, usually defined as zero-day attacks, cyber-security specialists known as threat hunters must be in organizations’ security departments. All the data generated by the organization’s users must be processed by those threat hunters (which are mainly benign and repetitive and follow predictable patterns) in short periods to detect unusual behaviors. The application of artificial intelligence, specifically machine learning (ML) techniques (for instance NLP, C-RNN-GAN, or GNN), can remarkably impact the real-time analysis of those data and help to discriminate between harmless data and malicious data, but not every technique is helpful in every circumstance; as a consequence, those specialists must know which techniques fit the best at every specific moment. The main goal of the present work is to design a distributed and scalable system for threat hunting based on ML, and with a special focus on critical infrastructure needs and characteristics.
An Enhanced Multi-Constraint Optimization Algorithm for Efficient Network Topology Generation
Authors: Wang Shangpeng , Zhang Liangliang , Fan Huilong
Published: August 2023

In order to address a problem in the research related to the low stability and communication efficiency issues in the generation of optical communication constellation network topology, there is a critical component for sensing the interaction among satellites. This paper makes a novel contribution by proposing a multi-constraint optimization algorithm for optical communication constellation network topology generation. The proposed method significantly improves the existing systems by considering multiple attributes that influence the establishment of inter-satellite links and reducing the impact of subjective factors. This unique approach involves calculating the entropy weight of each attribute using the information entropy method based on the degree of change in each indicator. Subsequently, the weights of the indicators are corrected to obtain the objective weight of each attribute. The comprehensive weight of the link, computed based on the initial link attribute values and weights, serves as the decision basis for link selection, thereby forming the satellite network topology. Upon evaluation, the proposed method has shown remarkable superiority over the compared schemes in terms of communication efficiency and stability.
On the Strength of a 316L-Type Austenitic Stainless Steel Produced by Selective Laser Melting
Authors: Odnobokova Marina , Torganchuk Vladimir , Tikhonova Marina , Dolzhenko Pavel , Kaibyshev Rustam , Belyakov Andrey
Published: August 2023

The developed microstructure and the tensile behavior of a 316L-type steel produced by selective laser melting were studied. This paper particularly aims to clarify the dislocation substructures in the developed steel, focusing on the density of dislocations, their arrangement in cells/subgrains, related internal distortions, and specific strengthening. The experimental samples were obtained using a 3D selective laser melting system ProX200 (laser power of 240 W, beam speed of 1070 mm/s, distance between tracks of 80 µm, and layer thickness of 30 µm) in a nitrogen atmosphere. The steel microstructure was characterized by a grain size of 20 μm and a high dislocation density of 5 × 1014 m−2 in the grain/subgrain interiors. The rather strong fiber texture of <012> along the building direction resulted in different Taylor factors of 2.89 and 3.30 for tension along the building direction and the side direction, respectively. The yield strength of 645 ± 5 MPa, the ultimate tensile strength of 750 ± 10 MPa, and an elongation of 40 ± 5% were obtained with a tensile test along the side direction. The rough calculation of the strengthening mechanisms suggested that the solid solution strengthening of 273 MPa and the dislocation strengthening of 262 MPa were the main contributors to the yield strength. Such a combination of strengthening from solid solution and homogeneously distributed numerous dislocations provides the processed steel with sufficient strengthening ability, leading to an outstanding strength–ductility combination.
Correction: Chaby et al. Cross-Platform Evaluation of Commercially Targeted and Untargeted Metabolomics Approaches to Optimize the Investigation of Psychiatric Disease. Metabolites 2021, 11, 609
Authors: Chaby Lauren E. , Lasseter Heather C. , Contrepois Kévin , Salek Reza M. , Turck Christoph W. , Thompson Andrew , Vaughan Timothy , Haas Magali , Jeromin Andreas
Published: August 2023

In the original publication [...]
Human Skin Drug Metabolism: Relationships between Methyl Salicylate Metabolism and Esterase Activities in IVPT Skin Membranes
Authors: Telaprolu Krishna C. , Grice Jeffrey E. , Mohammed Yousuf H. , Roberts Michael S.
Published: August 2023

The presence of esterase enzymes in human skin and their role in drug metabolism has been reported, but their distribution in the various skin layers and the relative contributions of those layers to metabolism is poorly defined. To gain further insight into esterase distribution, we performed in vitro skin permeation of a commercial 28.3% methyl salicylate (MeSA) cream (Metsal™) in Franz diffusion cells, using a range of human skin membranes, all from the same donor. The membranes were viable epidermis separated by a dispase II enzymatic method, heat separated epidermis, dermatomed skin, and dermis separated by a dispase II enzymatic method. Methyl salicylate and its metabolite, salicylic acid (SA), were measured by high-performance liquid chromatography. Alpha naphthyl acetate and Hematoxylin and Eosin staining provided qualitative estimations of esterase distribution in these membranes. The permeation of methyl salicylate after 24 h was similar across all membranes. Salicylic acid formation and permeation were found to be similar in dermatomed skin and dermis, suggesting dermal esterase activity. These results were supported by the staining studies, which showed strong esterase activity in the dermal–epidermal junction region of the dermis. In contrast with high staining of esterase activity in the stratum corneum and viable epidermis, minimal stained and functional esterase activity was found in heat-separated and dispase II-prepared epidermal membranes. The results are consistent with dispase II digesting hemidesmosomes, penetrating the epidermis, and affecting epidermal esterases but not those in the dermis. Accordingly, whilst the resulting dispase II-generated dermal membranes may be used for in vitro permeation tests (IVPT) involving esterase-based metabolic studies, the dispase II-generated epidermal membranes are not suitable for this purpose.
Ultrasound-Mediated Ocular Drug Delivery: From Physics and Instrumentation to Future Directions
Authors: Duncan Blair , Al-Kassas Raida , Zhang Guangming , Hughes Dave , Qiu Yongqiang
Published: August 2023

Drug delivery to the anterior and posterior segments of the eye is impeded by anatomical and physiological barriers. Increasingly, the bioeffects produced by ultrasound are being proven effective for mitigating the impact of these barriers on ocular drug delivery, though there does not appear to be a consensus on the most appropriate system configuration and operating parameters for this application. In this review, the fundamental aspects of ultrasound physics most pertinent to drug delivery are presented; the primary phenomena responsible for increased drug delivery efficacy under ultrasound sonication are discussed; an overview of common ocular drug administration routes and the associated ocular barriers is also given before reviewing the current state of the art of ultrasound-mediated ocular drug delivery and its potential future directions.
Mass Spectral Imaging to Map Plant–Microbe Interactions
Authors: Parker Gabriel D. , Hanley Luke , Yu Xiao-Ying
Published: August 2023

Plant–microbe interactions are of rising interest in plant sustainability, biomass production, plant biology, and systems biology. These interactions have been a challenge to detect until recent advancements in mass spectrometry imaging. Plants and microbes interact in four main regions within the plant, the rhizosphere, endosphere, phyllosphere, and spermosphere. This mini review covers the challenges within investigations of plant and microbe interactions. We highlight the importance of sample preparation and comparisons among time-of-flight secondary ion mass spectroscopy (ToF-SIMS), matrix-assisted laser desorption/ionization (MALDI), laser desorption ionization (LDI/LDPI), and desorption electrospray ionization (DESI) techniques used for the analysis of these interactions. Using mass spectral imaging (MSI) to study plants and microbes offers advantages in understanding microbe and host interactions at the molecular level with single-cell and community communication information. More research utilizing MSI has emerged in the past several years. We first introduce the principles of major MSI techniques that have been employed in the research of microorganisms. An overview of proper sample preparation methods is offered as a prerequisite for successful MSI analysis. Traditionally, dried or cryogenically prepared, frozen samples have been used; however, they do not provide a true representation of the bacterial biofilms compared to living cell analysis and chemical imaging. New developments such as microfluidic devices that can be used under a vacuum are highly desirable for the application of MSI techniques, such as ToF-SIMS, because they have a subcellular spatial resolution to map and image plant and microbe interactions, including the potential to elucidate metabolic pathways and cell-to-cell interactions. Promising results due to recent MSI advancements in the past five years are selected and highlighted. The latest developments utilizing machine learning are captured as an important outlook for maximal output using MSI to study microorganisms.
Genetic Diversity of Hepatitis B and C Viruses Revealed by Continuous Surveillance from 2015 to 2021 in Gabon, Central Africa
Authors: Abe Haruka , Ushijima Yuri , Bikangui Rodrigue , Ondo Georgelin Nguema , Pemba Christelle M. , Zadeh Vahid R. , Mpingabo Patrick I. , Ueda Hayato , Agnandji Selidji T. , Lell Bertrand , Yasuda Jiro
Published: August 2023

Viral hepatitis remains one of the largest public health concerns worldwide. Especially in Central Africa, information on hepatitis virus infections has been limited, although the prevalence in this region has been reported to be higher than the global average. To reveal the current status of hepatitis B and C virus (HBV and HCV) infections and the genetic diversity of the viruses, we conducted longitudinal surveillance in Gabon. We detected 22 HBV and 9 HCV infections in 2047 patients with febrile illness. Genetic analyses of HBV identified subgenotype A1 for the first time in Gabon and an insertion generating a frameshift to create an X-preC/C fusion protein. We also revealed that most of the detected HCVs belonged to the “Gabon-specific” HCV subtype 4e (HCV-4e), and the entire nucleotide sequence of the HCV-4e polyprotein was determined to establish the first reference sequence. The HCV-4e strains possessed resistance-associated substitutions similar to those of other HCV-4 strains, indicating that the use of direct-acting antiviral therapy may be complex. These results provide a better understanding of the current situation of hepatitis B and C virus infections in Central Africa and will help public health organizations develop effective countermeasures to eliminate chronic viral hepatitis in this region.
Characterisation of Variants of Cyclic di-GMP Turnover Proteins Associated with Semi-Constitutive rdar Morphotype Expression in Commensal and Uropathogenic Escherichia coli Strains
Authors: Cimdins-Ahne Annika , Naemi Ali-Oddin , Li Fengyang , Simm Roger , Römling Ute
Published: August 2023

Expression of rdar (red, dry, and rough) colony morphology-based biofilm formation in Escherichia coli is highly variable. To investigate the molecular mechanisms of semi-constitutive rdar morphotype formation, we compared their cyclic di-GMP turnover protein content and variability to the highly regulated, temperature-dependent morphotype of the historical and modern ST10 isolates E. coli MG1655 and Fec10, respectively. Subsequently, we assessed the effects of cyclic di-GMP turnover protein variants of the EAL phosphodiesterases YcgG and YjcC and the horizontally transferred diguanylate cyclase DgcX on biofilm formation and motility. The two YcgG variants with truncations of the N-terminal CSS signaling domain were oppositely effective in targeting downregulation of rdar biofilm formation compared to the full-length reference protein. Expression of the C-terminal truncated variants YjcCFec67 and YjcCTob1 showed highly diminished apparent phosphodiesterase activity compared to the reference YjcCMG1655. For YjcCFec101, substitution of the C-terminus led to an apparently inactive enzyme. Overexpression of the diguanylate cyclase DgcX contributed to upregulation of cellulose biosynthesis but not to elevated expression of the major biofilm regulator csgD in the “classical” rdar-expressing commensal strain E. coli Fec10. Thus, the c-di-GMP regulating network is highly complex with protein variants displaying substantially different apparent enzymatic activities.
Color Origin of Red Beds within the Danxia Basin, Southern China
Authors: He Wang , Yang Zhijun , Hu Jintao , Zhang Ke , Li Hongwei
Published: August 2023

Sedimentary facies color is an important paleoclimate indicator, but may be unreliable in thick continental red beds. The Danxia Formation is the landscape strata of the Danxia basin, and its color fluctuates between reddish-brown and reddish-purple vertically. This study examined the ferric oxides characteristics, distribution, and mineral composition of the Danxia Formation using a variety of analytical techniques, including optical microscopy, high-resolution scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and micro-Raman spectroscopy. The results indicate that the reddish-brown mineral is composed primarily of fine hematite with traces of goethite, while the reddish-purple mineral consists solely of fine hematite. These hematites exhibit a particle size range of submicron to micron and display various morphologies, including spherical, flake, and fibrous forms. Goethite particles are needle-shaped and often form star-shaped aggregates containing twins. Whole rock geochemical analysis reveals a strong positive correlation between iron and iron group elements, as well as phosphorus and rare earth elements. The findings suggest that the reddening of the Danxia Formation occurs during diagenesis, with fine hematite forming as a result of the alteration of iron-bearing detrital grains. In addition, vertical color variations in Danxia Formation are not attributable to the paleoclimate records, but rather the result of the differentiation of sediment sources. This study provides a novel viewpoint for examining the coloration of thick continental red beds in other regions.
Effect of Adding Intermediate Layers on the Interface Bonding Performance of WC-Co Diamond-Coated Cemented Carbide Tool Materials
Authors: Yang Junru , Yue Yanping , Lv Hao , Ren Baofei , Zhang Yuekan
Published: August 2023

The interface models of diamond-coated WC-Co cemented carbide (DCCC) were constructed without intermediate layers and with different interface terminals, such as intermediate layers of TiC, TiN, CrN, and SiC. The adhesion work of the interface model was calculated based on the first principle. The results show that the adhesion work of the interface was increased after adding four intermediate layers. Their effect on improving the interface adhesion performance of cemented carbide coated with diamond was ranked in descending order as follows: SiC > CrN > TiC > TiN. The charge density difference and the density of states were further analyzed. After adding the intermediate layer, the charge distribution at the interface junction was changed, and the electron cloud at the interface junction overlapped to form a more stable chemical bond. Additionally, after adding the intermediate layer, the density of states of the atoms at the interface increased in the energy overlapping area. The formant formed between the electronic orbitals enhances the bond strength. Thus, the interface bonding performance of DCCC was enhanced. Among them, the most obvious was the interatomic electron cloud overlapping at the diamond/SiCC-Si/WC-Co interface, its bond length was the shortest (1.62 Å), the energy region forming the resonance peak was the largest (−5–20 eV), and the bonding was the strongest. The interatomic bond length at the diamond/TiNTi/WC-Co interface was the longest (4.11 Å), the energy region forming the resonance peak was the smallest (−5–16 eV), and the bonding was the weakest. Comprehensively considering four kinds of intermediate layers, the best intermediate layer for improving the interface bonding performance of DCCC was SiC, and the worst was TiN.
Study of the Stability of Wine Samples for 1H-NMR Metabolomic Profile Analysis through Chemometrics Methods
Authors: García-Aguilera Martha E. , Delgado-Altamirano Ronna , Villalón Nayelli , Ruiz-Terán Francisco , García-Garnica Mariana M. , Ocaña-Ríos Irán , Rodríguez de San Miguel Eduardo , Esturau-Escofet Nuria
Published: August 2023

Wine is a temperature, light, and oxygen-sensitive product, so its physicochemical characteristics can be modified by variations in temperature and time when samples are either sampled, transported, and/or analyzed. These changes can alter its metabolomic fingerprinting, impacting further classification tasks and quality/quantitative analyses. For these reasons, the aim of this work is to compare and analyze the information obtained by different chemometric methods used in a complementary form (PCA, ASCA, and PARAFAC) to study 1H-NMR spectra variations of four red wine samples kept at different temperatures and time lapses. In conjunction, distinctive changes in the spectra are satisfactorily tracked with each chemometric method. The chemometric analyses reveal variations related to the wine sample, temperature, and time, as well as the interactions among these factors. Moreover, the magnitude and statistical significance of the effects are satisfactorily accounted for by ASCA, while the time-related effects variations are encountered by PARAFAC modeling. Acetaldehyde, formic acid, polyphenols, carbohydrates, lactic acid, ethyl lactate, methanol, choline, succinic acid, proline, acetoin, acetic acid, 1,3-propanediol, isopentanol, and some amino acids are identified as some of the metabolites which present the most important variations.
Analysis of Pork in Beef Sausages Using LC-Orbitrap HRMS Untargeted Metabolomics Combined with Chemometrics for Halal Authentication Study
Authors: Windarsih Anjar , Bakar Nor Kartini Abu , Dachriyanus  , Yuliana Nancy Dewi , Riswanto Florentinus Dika Octa , Rohman Abdul
Published: August 2023

Beef sausage (BS) is one of the most favored meat products due to its nutrition and good taste. However, for economic purposes, BS is often adulterated with pork by unethical players. Pork consumption is strictly prohibited for religions including Islam and Judaism. Therefore, advanced detection methods are highly required to warrant the halal authenticity of BS. This research aimed to develop a liquid chromatography–high-resolution mass spectrometry (LC–HRMS) method to determine the halal authenticity of BS using an untargeted metabolomics approach. LC–HRMS was capable of detecting various metabolites in BS and BS containing pork. The presence of pork in BS could be differentiated using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) with high accuracy. PLS-DA perfectly classified authentic BS and BS containing pork in all concentration levels of pork with R2X = (0.821), R2Y(= 0.984), and Q2 = (0.795). The level of pork in BS was successfully predicted through partial least squares (PLS) and orthogonal PLS (OPLS) chemometrics. Both models gave high R2 (>0.99) actual and predicted values as well as few errors, indicating good accuracy and precision. Identification of discriminating metabolites’ potential as biomarker candidates through variable importance for projections (VIP) value revealed metabolites of 2-arachidonyl-sn-glycero-3-phosphoethanolamine, 3-hydroxyoctanoylcarnitine, 8Z,11Z,14Z-eicosatrienoic acid, D-(+)-galactose, oleamide, 3-hydroxyhexadecanoylcarnitine, arachidonic acid, and α-eleostearic acid as good indicators to detect pork. It can be concluded that LC–HRMS metabolomics combined with PCA, PLS-DA, PLS, and OPLS was successfully used to detect pork adulteration in beef sausages. The results imply that LC–HRMS untargeted metabolomics in combination with chemometrics is a promising alternative as an analytical technique to detect pork in sausage products. Further analysis of larger samples is required to warrant the reproducibility.
Comparison of Reactive Sites in 2(1H)-Quinolone Derivatives for the Detection of Biologically Important Sulfur Compounds
Authors: Kolińska Jolanta , Grzelakowska Aleksandra , Szala Marcin , Podsiadły Radosław
Published: August 2023

Novel fluorescent probes based on 2(1H)-quinolone skeleton containing a malonate group (Q1–Q3) were synthesized and proposed for biothiols detection. Their chemical reactivity toward thiols was compared to the reactivity of derivative having a dicyanovinyl group (Q4) as a reactive site. The detailed photophysical properties of these compounds were assessed through the determination of absorption and fluorescence spectra, fluorescence quantum yield, and fluorescence lifetime. In the presence of biothiols, an increase in the fluorescence intensity of compounds Q1–Q3 and a hypsochromic shift in their emission bands were observed. In contrast, the compound with the dicyanovinyl group (Q4) in the presence of biothiols and cyanide ion showed the quenching of fluorescence, while a fluorescence “turn on” effect was observed toward reactive sulfur species.
Applications and Potential of In Silico Approaches for Psychedelic Chemistry
Authors: Karabulut Sedat , Kaur Harpreet , Gauld James W.
Published: August 2023

Molecular-level investigations of the Central Nervous System have been revolutionized by the development of computational methods, computing power, and capacity advances. These techniques have enabled researchers to analyze large amounts of data from various sources, including genomics, in vivo, and in vitro drug tests. In this review, we explore how computational methods and informatics have contributed to our understanding of mental health disorders and the development of novel drugs for neurological diseases, with a special focus on the emerging field of psychedelics. In addition, the use of state-of-the-art computational methods to predict the potential of drug compounds and bioinformatic tools to integrate disparate data sources to create predictive models is also discussed. Furthermore, the challenges associated with these methods, such as the need for large datasets and the diversity of in vitro data, are explored. Overall, this review highlights the immense potential of computational methods and informatics in Central Nervous System research and underscores the need for continued development and refinement of these techniques and more inclusion of Quantitative Structure-Activity Relationships (QSARs).
Possibilities and Limitations of ICP-Spectrometric Determination of the Total Content of Tin, Its Inorganic and Organic Speciations in Waters with Different Salinity Levels—Part 1: Determination of the Total Tin Content
Authors: Temerdashev Zaual , Abakumov Pavel , Bolshov Mikhail , Abakumova Darya , Pupyshev Alexander
Published: August 2023

This paper considers the features of determining the total tin content in waters with different salinity. Direct ICP-spectrometric analysis of sea waters with a salinity of more than 6‰ significantly reduced the analytical signal of tin by 70% (ICP-MS) and 30% (ICP-OES). The matrix effect of macrocomponents was eliminated by generating hydrides using 0.50 M sodium borohydride and 0.10 M hydrochloric acid. The effect of transition metals on the formation of tin hydrides was eliminated by applying L-cysteine at a concentration of 0.75 g/L. The total analyte concentrations, considering the content of organotin compounds, were determined after microwave digestion of sample with oxidizing mixtures based on nitric acid. The generation of hydrides with the ICP-spectrometric determination of tin leveled the influence of the sea water matrix and reduced its detection limit from 0.50 up to 0.05 µg/L for all digestion schemes. The developed analysis scheme made it possible to determine the total content of inorganic and organic forms of tin in sea waters. The total content of tin was determined in the waters of the Azov and Black seas at the levels of 0.17 and 0.24 µg/L, respectively.
Synthesis, Anti-Tyrosinase Activity, and Spectroscopic Inhibition Mechanism of Cinnamic Acid–Eugenol Esters
Authors: Li Jianping , Min Xiaofeng , Zheng Xi , Wang Shaohua , Xu Xuetao , Peng Jinbao
Published: August 2023

Tyrosinase plays crucial roles in mediating the production of melanin pigment; thus, its inhibitors could be useful in preventing melanin-related diseases. To find potential tyrosinase inhibitors, a series of cinnamic acid–eugenol esters (c1~c29) was synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR, HRMS, and FT-IR, respectively. The biological evaluation results showed that all compounds c1~c29 exhibited definite tyrosinase inhibitory activity; especially, compound c27 was the strongest tyrosinase inhibitor (IC50: 3.07 ± 0.26 μM), being ~4.6-fold stronger than the positive control, kojic acid (IC50: 14.15 ± 0.46 μM). Inhibition kinetic studies validated compound c27 as a reversible mixed-type inhibitor against tyrosinase. Three-dimensional fluorescence and circular dichroism (CD) spectra results indicated that compound c27 could change the conformation and secondary structure of tyrosinase. Fluorescence-quenching results showed that compound c27 quenched tyrosinase fluorescence in the static manner with one binding site. Molecular docking results also revealed the binding interactions between compound c27 and tyrosinase. Therefore, cinnamic acid–eugenol esters, especially c27, could be used as lead compounds to find potential tyrosinase inhibitors.
MOF-Based Biosensors for the Detection of Carcinoembryonic Antigen: A Concise Review
Authors: Ibrahim May R. , Greish Yaser E.
Published: August 2023

Cancer has been considered one of the most serious diseases in recent decades. Early diagnosis of cancer is a crucial step for expedited treatment. Ideally, detection of cancer biomarkers, which are usually elevated because of cancer, is the most straightforward approach to detecting cancer. Among these biomarkers, the carcinoembryonic antigen (CEA) is considered one of the most important tumor markers for colorectal cancer. The CEA has also been recognized as a biomarker for other types of cancers, including breast, gastric, ovarian, pancreatic, and lung cancers. Typically, conventional CEA testing depends on immunoassay approaches, which are known to be complex, highly expensive, and time consuming. Accordingly, various types of biosensors have been designed for the detection of cancer biomarkers. The main prerequisites of these biosensors are high sensitivity, fast response, and low cost. Many nanostructures have been involved in the design of biosensors, such as nanoparticles of certain metals and metal oxides that are further functionalized to contribute to the sensing of the biomarkers. Alternatively, metal organic frameworks (MOFs), which are extended crystalline structures comprising metal clusters surrounded by organic linkers, have been shown to be highly promising for the development of biosensors. The 3D structure of MOFs results in a combination of high surface area and high interconnected porosity, which are believed to facilitate their function in the design of a biosensor. This review briefly classifies and describes MOF-based biosensor trials that have been published recently for the aim of detecting CEA.
The Adsorption Behaviors of CO and H2 to FeO onto CaO Surfaces: A Density Functional Theory Study
Authors: Wang Ziming , Li Yaqiang , Dou Yaping , Li Kejiang , Yu Wanhai , Sheng Pengcheng
Published: August 2023

The adsorption behaviors of CO and H2 to FeO onto CaO surfaces have been studied using the density functional theory (DFT) to determine the reactions of FeO by CO and H2. The adsorption mechanisms of FeO clusters on the CaO(100) and CaO(110) surfaces were calculated first. The structure of the Ca(110) surface renders it highly chemically reactive compared with the Ca(100) surface because of low coordination. After gas adsorption, CO bonds to the O atom of FeO, forming CO2 compounds in both configurations through the C atom. H2 favors the O atom of FeO, forming H2O compounds and breaking the Fe-O bond. Comparing the adsorption behavior of two reducing gases to FeO on the Ca surface, the reaction of the CO molecule being adsorbed to generate CO2 compounds is exothermic. The reaction of H2 molecule adsorption to generate H2O compounds is endothermic. This property is essential for the inertial-collision stage of the reduction. However, the dissociation of the CO2 compound from the reaction interface will overcome a high energy barrier and slow down the reduction. The H2O compound dissociates from the surface more easily, which can accelerate the reduction.
MoS2/SnS/CoS Heterostructures on Graphene: Lattice-Confinement Synthesis and Boosted Sodium Storage
Authors: Zhang Ruyao , Dong Yan , Su Yu , Zhai Wenkai , Xu Sailong
Published: August 2023

The development of high-efficiency multi-component composite anode nanomaterials for sodium-ion batteries (SIBs) is critical for advancing the further practical application. Numerous multi-component nanomaterials are constructed typically via confinement strategies of surface templating or three-dimensional encapsulation. Herein, a composite of heterostructural multiple sulfides (MoS2/SnS/CoS) well-dispersed on graphene is prepared as an anode nanomaterial for SIBs, via a distinctive lattice confinement effect of a ternary CoMoSn-layered double-hydroxide (CoMoSn-LDH) precursor. Electrochemical testing demonstrates that the composite delivers a high-reversible capacity (627.6 mA h g−1 after 100 cycles at 0.1 A g−1) and high rate capacity of 304.9 mA h g−1 after 1000 cycles at 5.0 A g−1, outperforming those of the counterparts of single-, bi- and mixed sulfides. Furthermore, the enhancement is elucidated experimentally by the dominant capacitive contribution and low charge-transfer resistance. The precursor-based lattice confinement strategy could be effective for constructing uniform composites as anode nanomaterials for electrochemical energy storage.
Leading Edge Technologies and Perspectives in Industrial Oilseed Extraction
Authors: Cravotto Christian , Claux Ombéline , Bartier Mickaël , Fabiano-Tixier Anne-Sylvie , Tabasso Silvia
Published: August 2023

With the increase in the world’s population and per capita wealth, oil producers must not only increase edible oil production but also meet the demand for a higher quality and variety of products. Recently, the focus has shifted from single processing steps to the entire vegetable oil production process, with an emphasis on introducing innovative technologies to improve quality and production efficiency. In this review, conventional methods of oilseed storage, processing and extraction are presented, as well as innovative processing and extraction techniques. Furthermore, the parameters most affecting the products’ yields and quality at the industrial level are critically described. The extensive use of hexane for the extraction of most vegetable oils is undoubtedly the main concern of the whole production process in terms of health, safety and environmental issues. Therefore, special attention is paid to environmentally friendly solvents such as ethanol, supercritical CO2, 2-methyloxolane, water enzymatic extraction, etc. The state of the art in the use of green solvents is described and an objective assessment of their potential for more sustainable industrial processes is proposed.
Featured Reviews in Organic Chemistry
Authors: Dembinski Roman , Soloshonok Vadim
Published: August 2023

The field of Organic Chemistry represents one of the most traditional areas of chemistry that has delivered many benefits to the community of chemists [...]
Comprehensive Extraction and Chemical Characterization of Bioactive Compounds in Tepals of Crocus sativus L.
Authors: Ruggieri Fabrizio , Maggi Maria Anna , Rossi Michela , Consonni Roberto
Published: August 2023

Crocus sativus L. is largely cultivated because it is the source of saffron, a well-appreciated and valued spice, not only for its culinary use but also because of its significant biological activities. Stigmas are the main product obtained from flowers, but in addition, tepals, largely considered a waste product, represent a big source of flavonoids and anthocyanins. This study aimed to delve into the phytochemical composition of saffron tepals and investigate whether the composition was influenced by the extraction technique while investigating the main analytical techniques most suitable for the characterization of tepal extracts. The research focuses on flavonoids, a class of secondary metabolites, and their health benefits, including antioxidant, anti-inflammatory, and anticancer properties. Flavonoids occur as aglycones and glycosides and are classified into various classes, such as flavones, flavonols, and flavanones. The most abundant flavonoids in tepals are kaempferol glycosides, followed by quercetin and isorhamnetin glycosides. Overall, this review provides valuable insights into the potential uses of tepals as a source of bioactive compounds and their applications in various fields, promoting a circular and sustainable economy in saffron cultivation and processing.
Streptomyces iakyrus TA 36 as First-Reported Source of Quinone Antibiotic γ–Rubromycin
Authors: Charousová Ivana , Hlebová Miroslava , Hleba Lukas , Medo Juraj , Wink Joachim
Published: August 2023

A wide range of bioactive compounds with potential medical applications are produced by members of the genus Streptomyces. A new actinomycete producer of the antibiotic γ-rubromycin, designated TA 36, was isolated from an alpine soil sample collected in Peru (Machu Picchu). Morphological, physiological and biochemical characteristics of the strain, together with data obtained via phylogenetic analysis and MALDI-TOF MS, were used for the correct identification of the isolate. The isolate TA 36 showed morphological characteristics that were consistent with its classification within the genus Streptomyces. Phylogenetic analysis based on 16S rRNA gene sequences showed that the TA 36 strain was most similar to S. iakyrus and S. violaceochromogenes with 99% similarity. Phylogenetic analysis together with the profile of whole cell proteins indicated that the strain tested could be identified as S. iakyrus TA 36. The crude extract Ext.5333.TA 36 showed various effects against the tested organisms with strong antimicrobial activity in the growth of Staphylococcus aureus (Newman) (MIC value of 0.00195 µg/µL). HPLC fractionation and LC/MS analysis of the crude extract led to the identification of the quinone antibiotic γ-rubromycin, a promising antitumour and antibacterial antibiotic. To the best of our knowledge, there is currently no report on the production of γ-rubromycin by S. iakyrus. Therefore, this study suggests S. iakyrus TA 36 as the first-reported source of this unique bioactive secondary metabolite.
Malondialdehyde as a Potential Oxidative Stress Marker for Allergy-Oriented Diseases: An Update
Authors: Cordiano Raffaele , Di Gioacchino Mario , Mangifesta Rocco , Panzera Claudia , Gangemi Sebastiano , Minciullo Paola Lucia
Published: August 2023

Malondialdehyde (MDA) is a compound that is derived from the peroxidation of polyunsaturated fatty acids. It has been used as a biomarker to measure oxidative stress in various biological samples in patients who are affected by a wide range of diseases. The aim of our work is to provide an updated overview of the role of MDA as a marker of oxidative stress in allergy-related diseases. We considered studies involving both paediatric and adult patients affected by rhinitis, asthma, urticaria and atopic dermatitis. The measurement of MDA was performed on different types of samples. The reported data highlight the role of serum MDA in inflammatory airway diseases. According to the literature review, the oxidative stress status in asthmatic patients, assessed via MDA determination, appears to worsen in the presence of other allergic airway diseases and in relation to the disease severity. This suggests that MDA can be a suitable marker for monitoring the disease status. However, there are several limitations in the considered studies due to the different samples used and the lack of phenotyping and description of the clinical period of patients examined. In cutaneous allergic diseases, the role of MDA is controversial because of the smallness of the studies and the heterogeneity of the samples and patients.
Incorporation of Copper Nanoparticles on Electrospun Polyurethane Membrane Fibers by a Spray Method
Authors: Al Kayal Tamer , Giuntoli Giulia , Cavallo Aida , Pisani Anissa , Mazzetti Paola , Fonnesu Rossella , Rosellini Alfredo , Pistello Mauro , D’Acunto Mario , Soldani Giorgio , Losi Paola
Published: August 2023

Electrospinning is an easy and versatile technique to obtain nanofibrous membranes with nanosized fibers, high porosity, and pore interconnectivity. Metal nanoparticles (e.g., Ag, Cu, ZnO) exhibit excellent biocide properties due to their size, shape, release of metal ions, or reactive oxygen species production, and thus are often used as antimicrobial agents. In this study, a combined electrospinning/spray technique was employed to fabricate electrospun polyurethane membranes loaded with copper nanoparticles at different surface densities (10, 20, 25, or 30 μg/cm2). This method allows particle deposition onto the surface of the membranes without the use of chemical agents. SEM images showed that polyurethane fibers own homogeneous thickness (around 650 nm), and that spray-deposited copper nanoparticles are evenly distributed. STEM-EDX demonstrated that copper nanoparticles are deposited onto the surface of the fibers and are not covered by polyurethane. Moreover, a uniaxial rupture test showed that particles are firmly anchored to the electrospun fibers. Antibacterial tests against model microorganisms Escherichia coli indicated that the prepared electrospun membranes possess good bactericidal effect. Finally, the antiviral activity against SARS-CoV-2 was about 90% after 1 h of direct contact. The obtained results suggested that the electrospun membranes possess antimicrobial activities and can be used in medical and industrial applications.
High-Power-Density Thermoelectrochemical Cell Based on Ni/NiO Nanostructured Microsphere Electrodes with Alkaline Electrolyte
Authors: Artyukhov Denis , Kiselev Nikolay , Boychenko Elena , Asmolova Aleksandra , Zheleznov Denis , Artyukhov Ivan , Burmistrov Igor , Gorshkov Nikolay
Published: August 2023

Effective low-grade waste heat harvesting and its conversion into electric energy by the means of thermoelectrochemical cells (TECs) are a strong theme in the field of renewable energy investigation. Despite considerable scientific research, TECs have not yet been practically applied due to the high cost of electrode materials and low effectiveness levels. A large hypothetical Seebeck coefficient allow the harvest of the low-grade waste heat and, particularly, to use TECs for collecting human body heat. This paper demonstrates the investigation of estimated hypothetical Seebeck coefficient dependency on KOH electrolyte concentration for TECs with hollow nanostructured Ni/NiO microsphere electrodes. It proposes a thermoelectrochemical cell with power density of 1.72 W·m−2 and describes the chemistry of electrodes and near-electrode space. Also, the paper demonstrates a decrease in charge transfer resistance from 3.5 to 0.52 Ω and a decrease in capacitive behavior with increasing electrolyte concentration due to diffusion effects.
Ag Sinter Bonding to Si Substrate via Temporal Formation and Decomposition of Ag Carboxylate
Authors: Matsuda Tomoki , Kawabata Rei , Okamoto Takuya , Hirose Akio
Published: August 2023

This paper demonstrates the in situ sinter bonding of Ag microparticle pastes to a Si substrate via the temporal formation and decomposition of Ag carboxylate on the surface of Ag microparticles. This was proposed via the investigation of Ag sinter bonding using the redox reaction between Ag2O and ethylene glycol, which achieved a bonding strength above 30 MPa even for the bonding temperature at 220 °C. Thermal analysis was used to identify the product of the redox reaction between Ag2O and ethylene glycol and determine the bonding temperature because the final reaction facilitates the interfacial sinter bonding with the substrate. Fourier-transform infrared spectroscopy and nuclear magnetic resonance results indicated the in situ formation of Ag salts of carboxylic acids, such as Ag oxalate on the surface of Ag microparticles. Therefore, the sinter bonding process enabled by the in situ formation and subsequent decomposition of these Ag salts was investigated using Ag microparticles and oxalic acid. Observations of the surface and interfacial morphology of the Ag particles after heating revealed the formation of Ag nanoparticles on the surfaces of the microparticles and the formation of sintering necks between the particles. The bonding experiments demonstrated a significant increase in strength with the addition of oxalic acid to the Ag paste due to the enhanced interfacial sinter bonding with the substrate. The in situ formation and decomposition of Ag salts are promising strategies for improving sintered bonds in electronic devices because they can provide enhanced localized sinter bonding using stable insert materials.