bluuebunny/crossref_metadata_2025 huggingface dataset:
Sugar Coating: Utilisation of Host Serum Sialoglycoproteins by Schistosoma mansoni as a Potential Immune Evasion Mechanism
Authors: Dagenais Maude , Gerlach Jared Q. , Geary Timothy G. , Long Thavy
Published: April 2022

Parasitic helminths resort to various mechanisms to evade and modulate their host’s immune response, several of which have been described for Schistosoma mansoni. We recently reported the presence of sialic acid residues on the surface of adult S. mansoni extracellular vesicles (EVs). We now report that these sialylated molecules are mammalian serum proteins. In addition, our data suggest that most sialylated EV-associated proteins do not elicit a humoral response upon injection into mice, or in sera obtained from infected animals. Sialic acids frequently terminate glycans on the surface of vertebrate cells, where they serve important functions in physiological processes such as cell adhesion and signalling. Interestingly, several pathogens have evolved ways to mimic or utilise host sialic acid beneficially by coating their own proteins, thereby facilitating cell invasion and providing protection from host immune effectors. Together, our results indicate that S. mansoni EVs are coated with host glycoproteins, which may contribute to immune evasion by masking antigenic sites, protecting EVs from removal from serum and aiding in cell adhesion and entry to exert their functions.
Euphorbia supina Extracts Block NADPH Oxidase-Mediated, Ceramide-Induced Apoptosis Initiated by Diesel Particulate Matter
Authors: Shin Kyong-Oh , Kim Sungeun , Kim Bokyung , Park Hye-Yoon , Jung Eunhee , Kim Garyun , Kim Donghee , Cho Hwang Eui , Uchida Yoshikazu , Park Kyungho
Published: April 2022

Air pollutants contribute to the development of diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary cancer, cardiovascular problems, and some skin diseases. We recently found that a major air pollutant, diesel particulate matter (DPM), induces apoptosis in human keratinocytes by increasing a proapoptotic lipid mediator, ceramide. DPM activates nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), which stimulates sphingomyelinase, leading to an increased conversion of sphingomyelin to ceramide. Interestingly, we characterized that although NOX is a reactive oxygen species (ROS) generator, the activation of sphingomyelinases by NOX is an ROS-independent mechanism. A Korean weed, prostrate spurge Euphorbia supina Rafin (ESR), has been used for centuries as a folk medicine to treat bronchitis, hepatitis, hemorrhage, and skin inflammation. Flavonoids, terpenes and tannins are enriched in ESR, and although ESR has proven antioxidative activity, its biological activities are largely unknown. Here, we investigate whether and how ESR protects keratinocytes against DPM-mediated apoptosis. We found that ESR-extracts (ESR-Ex) protect keratinocytes from DPM-induced apoptosis by inhibiting NOX activation in keratinocytes in response to DPM. We also demonstrated that ESR-Ex suppresses NOX activation via a blockage of the aryl hydrocarbon receptor (AhR) activation-mediated transcription of neutrophil cytosolic factor 1 (NCF1)/p47phox, a subunit of NOX. Our study reveals previously uncharacterized biological activity of ESR-Ex; i.e., its inhibition of Ahr and NOX activation. Thus, because the inhibition of NOX has already been developed to treat NOX-mediated diseases, including various types of cardiovascular diseases and cancers, initiated by air pollutants and because AhR activation contributes to the development of chronic inflammatory diseases, our study provides further advantages for the medical use of ESR.
Neuronal Hyperexcitability and Free Radical Toxicity in Amyotrophic Lateral Sclerosis: Established and Future Targets
Authors: Shibuya Kazumoto , Otani Ryo , Suzuki Yo-ichi , Kuwabara Satoshi , Kiernan Matthew C.
Published: April 2022

Amyotrophic lateral sclerosis (ALS) is a devastating disease with evidence of degeneration involving upper and lower motor neuron compartments of the nervous system. Presently, two drugs, riluzole and edaravone, have been established as being useful in slowing disease progression in ALS. Riluzole possesses anti-glutamatergic properties, while edaravone eliminates free radicals (FRs). Glutamate is the excitatory neurotransmitter in the brain and spinal cord and binds to several inotropic receptors. Excessive activation of these receptors generates FRs, inducing neurodegeneration via damage to intracellular organelles and upregulation of proinflammatory mediators. FRs bind to intracellular structures, leading to cellular impairment that contributes to neurodegeneration. As such, excitotoxicity and FR toxicities have been considered as key pathophysiological mechanisms that contribute to the cascade of degeneration that envelopes neurons in ALS. Recent advanced technologies, including neurophysiological, imaging, pathological and biochemical techniques, have concurrently identified evidence of increased excitability in ALS. This review focuses on the relationship between FRs and excitotoxicity in motor neuronal degeneration in ALS and introduces concepts linked to increased excitability across both compartments of the human nervous system. Within this cellular framework, future strategies to promote therapeutic development in ALS, from the perspective of neuronal excitability and function, will be critically appraised.
ZLN005 Alleviates In Vivo and In Vitro Renal Fibrosis via PGC-1α-Mediated Mitochondrial Homeostasis
Authors: Zhu Pengfei , Ma Haijian , Cui Shichao , Zhou Xiqiao , Xu Weilong , Yu Jiangyi , Li Jingya
Published: April 2022

Currently, chronic kidney disease (CKD) is one of the most common diseases; it is also a serious threat to human health due to its high mortality, and its treatment is still a major clinical challenge. Mitochondrial dyshomeostasis plays an important role in the development of CKD. ZLN005 is a novel peroxisome-proliferator-activated receptor-γ coactivator-1α (PGC-1α) activator from our laboratory. To explore whether ZLN005 can protect against CKD in vivo and in vitro, a unilateral ureteral obstruction (UUO) model and TGF-β1-treated renal tubular epithelial cells (TECs), respectively, were used in this study. We found that ZLN005-administrated UUO mice showed less kidney damages than control mice, as indicated by the reduced expression of fibrotic biomarkers in the kidney of UUO mice. ZLN005 treatment also alleviated the TGF-β1-induced fibrotic phenotype and lipid accumulation in TECs. Our study demonstrated ZLN005 treatment improved mitochondrial homeostasis at least partially via the activation of PGC-1α, thus maintaining mitochondria function and energy homeostasis. In summary, ZLN005 treatment ameliorates UUO-induced renal fibrosis, providing conceptional support for mitochondria-targeting therapies for chronic kidney disease.
Rosmarinic Acid Attenuates the Lipopolysaccharide-Provoked Inflammatory Response of Vascular Smooth Muscle Cell via Inhibition of MAPK/NF-κB Cascade
Authors: Chen Ching-Pei , Lin You-Cian , Peng Yu-Hui , Chen Han-Min , Lin Jiun-Tsai , Kao Shao-Hsuan
Published: April 2022

Rosmarinic acid (RA) is a phenolic compound that has several bioactivities, such as anti-inflammatory and antioxidant activities. Here, we further investigate the anti-inflammatory effect of RA on rat A7r5 aortic smooth muscle cells with exposure to lipopolysaccharide (LPS). Our findings showed that low-dose RA (10–25 μM) did not influence the cell viability and morphology of A7r5 cells and significantly inhibited LPS-induced mRNA expression of the pro-inflammatory mediators TNFα, IL-8, and inducible NO synthase (iNOS). Consistently, RA reduced the production of TNFα, IL-8, and NO by A7r5 cells with exposure to LPS. Signaling cascade analysis showed that LPS induced activation of Erk, JNK, p38 mitogen-activated protein kinase (MAPK), and NF-κB, and RA treatments attenuated the activation of the three MAPKs and NF-κB. Moreover, cotreatment with RA and Erk, JNK, p38 MAPK, or NF-κB inhibitors further downregulated the mRNA expression of TNFα, IL-8, and iNOS, and decreased the production of TNFα, IL-8, and NO by A7r5 cells. Taken together, these findings indicate that RA may ameliorate the LPS-provoked inflammatory response of vascular smooth muscle cells by inhibition of MAPK/NF-κB signaling.
Designer Functional Nanomedicine for Myocardial Repair by Regulating the Inflammatory Microenvironment
Authors: Liu Chunping , Fan Zhijin , He Dongyue , Chen Huiqi , Zhang Shihui , Guo Sien , Zheng Bojun , Cen Huan , Zhao Yunxuan , Liu Hongxing , Wang Lei
Published: April 2022

Acute myocardial infarction is a major global health problem, and the repair of damaged myocardium is still a major challenge. Myocardial injury triggers an inflammatory response: immune cells infiltrate into the myocardium while activating myofibroblasts and vascular endothelial cells, promoting tissue repair and scar formation. Fragments released by cardiomyocytes become endogenous “danger signals”, which are recognized by cardiac pattern recognition receptors, activate resident cardiac immune cells, release thrombin factors and inflammatory mediators, and trigger severe inflammatory responses. Inflammatory signaling plays an important role in the dilation and fibrosis remodeling of the infarcted heart, and is a key event driving the pathogenesis of post-infarct heart failure. At present, there is no effective way to reverse the inflammatory microenvironment in injured myocardium, so it is urgent to find new therapeutic and diagnostic strategies. Nanomedicine, the application of nanoparticles for the prevention, treatment, and imaging of disease, has produced a number of promising applications. This review discusses the treatment and challenges of myocardial injury and describes the advantages of functional nanoparticles in regulating the myocardial inflammatory microenvironment and overcoming side effects. In addition, the role of inflammatory signals in regulating the repair and remodeling of infarcted hearts is discussed, and specific therapeutic targets are identified to provide new therapeutic ideas for the treatment of myocardial injury.
Dendrimers as Antiamyloid Agents
Authors: Sorokina Svetlana A. , Shifrina Zinaida B.
Published: April 2022

Dendrimer–protein conjugates have significant prospects for biological applications. The complexation changes the biophysical behavior of both proteins and dendrimers. The dendrimers could influence the secondary structure of proteins, zeta-potential, distribution of charged regions on the surface, the protein–protein interactions, etc. These changes offer significant possibilities for the application of these features in nanotheranostics and biomedicine. Based on the dendrimer–protein interactions, several therapeutic applications of dendrimers have emerged. Thus, the formation of stable complexes retains the disordered proteins on the aggregation, which is especially important in neurodegenerative diseases. To clarify the origin of these properties and assess the efficiency of action, the mechanism of protein–dendrimer interaction and the nature and driving force of binding are considered in this review. The review outlines the antiamyloid activity of dendrimers and discusses the effect of dendrimer structures and external factors on their antiamyloid properties.
NMS-873 Leads to Dysfunctional Glycometabolism in A p97-Independent Manner in HCT116 Colon Cancer Cells
Authors: Li Shan , Wang Feng , Zhang Gang , Chou Tsui-Fen
Published: April 2022

Adenosine triphosphate (ATP)–competitive p97 inhibitor CB-5339, the successor of CB-5083, is being evaluated in Phase 1 clinical trials for anti-cancer therapy. Different modes-of-action p97 inhibitors such as allosteric inhibitors are useful to overcome drug-induced resistance, one of the major problems of targeted therapy. We previously demonstrated that allosteric p97 inhibitor NMS-873 can overcome CB-5083-induced resistance in HCT116. Here we employed chemical proteomics and drug-induced thermal proteome changes to identify drug targets, in combination with drug-resistant cell lines to dissect on- and off-target effects. We found that NMS-873 but not CB-5083 affected glycometabolism. By establishing NMS-873-resistant HCT116 cell lines and performing both cell-based and proteomic analysis, we confirmed that NMS-873 dysregulates glycometabolism in a p97-independent manner. We then used proteome integral solubility alteration with a temperature-based method (PISA T) to identify NDUFAF5 as one of the potential targets of NMS-873 in the mitochondrial complex I. We also demonstrated that glycolysis inhibitor 2-DG enhanced the anti-proliferative effect of NMS-873. The polypharmacology of NMS-873 can be advantageous for anti-cancer therapy for colon cancer.
Second-Order Scattering Quenching in Fluorescence Spectra of Natural Humates as a Tracer of Formation Stable Supramolecular System for the Delivery of Poorly Soluble Antiviral Drugs on the Example of Mangiferin and Favipiravir
Authors: Morozova Mariya A. , Tumasov Vladimir N. , Kazimova Ilaha V. , Maksimova Tatiana V. , Uspenskaya Elena V. , Syroeshkin Anton V.
Published: April 2022

In the present work, the methods of dynamic light scattering and fluorescence spectroscopy were applied to study the optical properties of aqueous dilutions of the humic substances complex (HC) as a potential drug delivery system. The supramolecular structures in the humate solution were characterized as monodisperse systems of the submicron range with a tendency to decrease in particle size with a decrease in the dry matter concentration. The slightly alkaline medium (8.3) of the studied aqueous dilutions of HC causes the absence of a pronounced fluorescence maximum in the region from 400 to 500 nm. However, the presence of an analytically significant, inversely proportional to the concentration second-order scattering (SOS) signal at 2λex = λem was shown. In the examples of the antiviral substances mangiferin and favipiravir, it was shown that the use of the humic complex as a drug carrier makes it possible to increase the solubility by several times and simultaneously obtain a system with a smaller particle size of the dispersed phase. It has been shown that HC can interact with mangiferin and favipiravir to form stable structures, which lead to a significant decrease in SOS intensities on HC SOS spectra. The scattering wavelengths, λex/λem, were registered at 350 nm/750 nm for mangiferin and 365 nm/730 nm for favipiravir, respectively. The increments of the scattering intensities (I0/I) turned out to be proportional to the concentration of antiviral components in a certain range of concentrations.
Development and Dissolution Study of a β-Galactosidase Containing Drinking Straw
Authors: Király Márton , Sántha Konrád , Kállai-Szabó Barnabás , Pencz Kriszta Mariann , Ludányi Krisztina , Kállai-Szabó Nikolett , Antal István
Published: April 2022

Today, in addition to many different physicochemical and pharmacological properties of the active ingredients and excipients, the developer of a pharmaceutical formulation must take into account several factors during the formulation process in order for the patient to cooperate to use the formulation accurately. One of the innovative solutions in paediatrics may be the use of medicated drinking straws. For our studies, we successfully prepared lactase-containing, rapid disintegration particles by two techniques commonly used in the pharmaceutical industry. The simulation of the usage of the filled straws was presented from a new perspective for the patient by an in vitro method. The effect of the temperature of the liquid used during the administration of the straw and the effect of the frequency during the application on the dissolution rate were investigated. According to our results, in the case of a straw containing rapidly dissolving particles, the temperature of the used liquid and the mode of administration (frequency) play a significant role in the release rate from the composition.
Inorganic Nanoparticles in Bone Healing Applications
Authors: Burdușel Alexandra-Cristina , Gherasim Oana , Andronescu Ecaterina , Grumezescu Alexandru Mihai , Ficai Anton
Published: April 2022

Modern biomedicine aims to develop integrated solutions that use medical, biotechnological, materials science, and engineering concepts to create functional alternatives for the specific, selective, and accurate management of medical conditions. In the particular case of tissue engineering, designing a model that simulates all tissue qualities and fulfills all tissue requirements is a continuous challenge in the field of bone regeneration. The therapeutic protocols used for bone healing applications are limited by the hierarchical nature and extensive vascularization of osseous tissue, especially in large bone lesions. In this regard, nanotechnology paves the way for a new era in bone treatment, repair and regeneration, by enabling the fabrication of complex nanostructures that are similar to those found in the natural bone and which exhibit multifunctional bioactivity. This review aims to lay out the tremendous outcomes of using inorganic nanoparticles in bone healing applications, including bone repair and regeneration, and modern therapeutic strategies for bone-related pathologies.
Period-One Laser Dynamics for Photonic Microwave Signal Generation and Applications
Authors: Zhou Pei , Li Nianqiang , Pan Shilong
Published: April 2022

Due to the advantages of rich dynamics, small size, and easy integration, semiconductor lasers have many applications in microwave photonics. With a proper perturbation to invoke period-one (P1) nonlinear laser dynamics, a widely tunable microwave signal can be generated. In this paper, we concentrate on the realization and application of photonic microwave signal generation based on the P1 oscillation state of semiconductor lasers. Recent developments in P1 dynamics-based tunable microwave signal generation techniques are reviewed with an emphasis on the optical injection system, which has a large frequency tuning range that is far beyond the intrinsic relaxation oscillation frequency. In order to improve the spectral purity and stability of the generated microwave signal, two typical approaches are introduced, i.e., microwave modulation stabilization, and delayed feedback stabilization. Various applications of the P1 dynamics-based microwave signal generator in diverse signal generation and photonic microwave signal processing are described. Development trends of the P1 dynamics-based photonic microwave signal generator are also discussed.
DNA-Based Identification of Eurasian Vicia Species Using Chloroplast and Nuclear DNA Barcodes
Authors: Bosmali Irene , Lagiotis Georgios , Haider Nadia , Osathanunkul Maslin , Biliaderis Costas , Madesis Panagiotis
Published: April 2022

Many legume species of the Vicia L. genus (Fabaceae Lindl.) are key components of the Mediterranean diet and have an integral role in sustainable agriculture. Given the importance of the Vicia species for Eurasian culture, it is necessary to implement methodologies, such as DNA barcoding, that can enable the effective authentication and identification of species in the genus. In this study, we analysed the chloroplast trnL and rpoC1, as well as the nuclear ITS2 DNA barcoding regions, to identify 71 Vicia specimens of Eurasian descent. Both the trnL and ITS2 regions were highly effective in discriminating the analysed taxa, while the more conserved rpoC1 region could not identify all of the selected species due to high sequence conservation or non-annotated or absent rpoC1 species sequences in GenBank. A dendrographic representation of the generated trnL data showed sufficient clustering for most of the analysed taxa, although some topological discrepancies were observed. ITS2 and rpoC1 reconstructions were also used for resolving the topological discrepancies observed in the trnL tree. Our analysis suggests that a combination of DNA barcoding regions is essential for accurate species discrimination within the Vicia genus, while single-locus analyses do not provide the necessary resolution.
Genetic Potential and Inheritance Patterns of Physiological, Agronomic and Quality Traits in Bread Wheat under Normal and Water Deficit Conditions
Authors: Kamara Mohamed , Rehan Medhat , Mohamed Amany , El Mantawy Rania , Kheir Ahmed , Abd El-Moneim Diaa , Safhi Fatmah , ALshamrani Salha , Hafez Emad , Behiry Said , Ali Mohamed , Mansour Elsayed
Published: April 2022

Water scarcity is a major environmental stress that adversatively impacts wheat growth, production, and quality. Furthermore, drought is predicted to be more frequent and severe as a result of climate change, particularly in arid regions. Hence, breeding for drought-tolerant and high-yielding wheat genotypes has become more decisive to sustain its production and ensure global food security with continuing population growth. The present study aimed at evaluating different parental bread wheat genotypes (exotic and local) and their hybrids under normal and drought stress conditions. Gene action controlling physiological, agronomic, and quality traits through half-diallel analysis was applied. The results showed that water-deficit stress substantially decreased chlorophyll content, photosynthetic efficiency (FV/Fm), relative water content, grain yield, and yield attributes. On the other hand, proline content, antioxidant enzyme activities (CAT, POD, and SOD), grain protein content, wet gluten content, and dry gluten content were significantly increased compared to well-watered conditions. The 36 evaluated genotypes were classified based on drought tolerance indices into 5 groups varying from highly drought-tolerant (group A) to highly drought-sensitive genotypes (group E). The parental genotypes P3 and P8 were identified as good combiners to increase chlorophyll b, total chlorophyll content, relative water content, grain yield, and yield components under water deficit conditions. Additionally, the cross combinations P2 × P4, P3 × P5, P3 × P8, and P6 × P7 were the most promising combinations to increase yield traits and multiple physiological parameters under water deficit conditions. Furthermore, P1, P2, and P5 were recognized as promising parents to improve grain protein content and wet and dry gluten contents under drought stress. In addition, the crosses P1 × P4, P2 × P3, P2 × P5, P2 × P6, P4 × P7, P5 × P7, P5 × P8, P6 × P8, and P7 × P8 were the best combinations to improve grain protein content under water-stressed and non-stressed conditions. Certain physiological traits displayed highly positive associations with grain yield and its contributing traits under drought stress such as chlorophyll a, chlorophyll b, total chlorophyll content, photosynthetic efficiency (Fv/Fm), proline content, and relative water content, which suggest their importance for indirect selection under water deficit conditions. Otherwise, grain protein content was negatively correlated with grain yield, indicating that selection for higher grain yield could reduce grain protein content under drought stress conditions.
Chemical Composition, Antioxidant and Antibacterial Activities of Thymus broussonetii Boiss and Thymus capitatus (L.) Hoffmann and Link Essential Oils
Authors: Tagnaout Imane , Zerkani Hannou , Hadi Nadia , El Moumen Bouchra , El Makhoukhi Fadoua , Bouhrim Mohamed , Al-Salahi Rashad , Nasr Fahd A. , Mechchate Hamza , Zair Touriya
Published: April 2022

Thymus capitatus and Thymus broussonnetii are two Moroccan endemic medicinal plants used traditionally by the local population. The present study aims to investigate their essential oil chemical composition, antioxidant and antibacterial activities. The chemical composition of the essential oils was determined using the GC-MS analysis, the antioxidant activity assessed using DPPH and FRAP methods while the antimicrobial activity was evaluated against nine bacteria species tested (Enterococcus faecalis, Serratia fonticola, Acinetobacter baumannii, Klebsiella oxytoca, sensitive Klebsiella pneumoniae, sensitive Escherichia coli, resistant Escherichia coli, resistant Staphylococcus aureus and Enterobacter aerogenes). The major identified compounds of T. capitatus essential oil where carvacrol (75%) and p-cymene (10.58%) while carvacrol (60.79%), thymol (12.9%), p-cymene (6.21%) and γ-terpinene (4.47%) are the main compounds in T. broussonnetii essential oil. The bioactivity of the essential oils of the two species of thyme was explained by their richness in oxygenated monoterpenes known for their great effectiveness with an IC50 of 3.48 ± 0.05 and 4.88 ± 0.04 μL/mL and EC50 of 0.12 ± 0.01 and 0.20 ± 0.02 μL/mL in the DPPH and FRAP assays, respectively, with an important antibacterial activity. These results encourage the use of these plants as a source of natural antioxidants, and antibacterial additives, to protect food from oxidative damage and to eliminate bacteria that are responsible for nosocomial infections.
Prediction of the Compressive Strength of Fly Ash Geopolymer Concrete by an Optimised Neural Network Model
Authors: Khalaf Ali Abdulhasan , Kopecskó Katalin , Merta Ildiko
Published: April 2022

This article presents a regression tool for predicting the compressive strength of fly ash (FA) geopolymer concrete based on a process of optimising the Matlab code of a feedforward layered neural network (FLNN). From the literature, 189 samples of different FA geopolymer concrete mix-designs were collected and analysed according to ten input variables (all relevant mix-design parameters) and the output variable (cylindrical compressive strength). The developed optimal FLNN model proved to be a powerful tool for predicting the compressive strength of FA geopolymer concrete with a small range of mean squared error (MSE = 10.4 and 15.0), a high correlation coefficient with the actual values (R = 96.0 and 97.5) and a relatively small root mean squared error (RMSE = 3.22 and 3.87 MPa) for the training and testing data, respectively. Based on the optimised model, a powerful design chart for determining the mix-design parameters of FA geopolymer concretes was generated. It is applicable for both one- and two-part geopolymer concretes, as it takes a wide range of mix-design parameters into account. The design chart (with its relatively small error) will ensure cost- and time-efficient geopolymer production in future applications.
Polymer Concentration and Liquid—Liquid Demixing Time Correlation with Porous Structure of Low Dielectric Polyimide in Diffusion-Driven Phase Separation
Authors: Kim Subin , Son Jaemin , Park Hwon , Jeong Euigyung , Nam Ki-Ho , Bae Jin-Seok
Published: April 2022

Porous polyimide (PI) films are a promising low-k dielectric material for high-frequency data transmission with low signal attenuation. Pores are generated by non-solvent induced phase separation (NIPS) during phase inversion of polymer solution via non-solvent accumulation and solvent diffusion. In this study, aromatic PI was employed as a matrix for NIPS, and the influence of polymer concentration and liquid—liquid demixing time on the morphology of pores in the PI films was investigated. This ensured control over the porous structure of the PI film and provided desirable dielectric properties in a broad frequency range of 100 Hz–30 MHz (1.99 at 30 MHz) and thermal stability (Td5% > 576 °C, Tg > 391 °C). This study addresses the effect of polymer concentration and coagulation time on the morphology and physical properties of PI sponge films and provides guidance on the design and optimization of architectures for polymeric materials requiring pore modification.
Synthesis of Half-Titanocene Complexes Containing π,π-Stacked Aryloxide Ligands, and Their Use as Catalysts for Ethylene (Co)polymerizations
Authors: Gu Jin , Wang Xiaohua , Zhao Wenpeng , Zhuang Rui , Zhang Chunyu , Zhang Xuequan , Cai Yinghui , Yuan Wenbo , Luan Bo , Dong Bo , Liu Heng
Published: April 2022

A family of half-titanocene complexes bearing π,π-stacked aryloxide ligands and their catalytic performances towards ethylene homo-/co- polymerizations were disclosed herein. All the complexes were well characterized, and the intermolecular π,π-stacking interactions could be clearly identified from single crystal X-ray analysis, in which a stronger interaction could be reflected for aryloxides bearing bigger π-systems, e.g., pyrenoxide. Due to the formation of such interactions, these complexes were able to highly catalyze the ethylene homopolymerizations and copolymerization with 1-hexene comonomer, even without any additiveson the aryloxide group, which showed striking contrast to other half-titanocene analogues, implying the positive influence of π,π-stacking interaction in enhancing the catalytic performances of the corresponding catalysts. Moreover, it was found that addition of external pyrene molecules was capable of boosting the catalytic efficiency significantly, due to the formation of a stronger π,π-stacking interaction between the complexes and pyrene molecules.
Study of a Novel Electrochromic Device with Crystalline WO3 and Gel Electrolyte
Authors: Chen Wanyu , Zhang Guixia , Wu Lili , Liu Siyuan , Cao Meng , Yang Ying , Peng Yong
Published: April 2022

Most ECDs are coated with an electrochromic material on the transparent conductive oxide (TCO) substrate. A novel electrochromic device (ECD), having a variable optical performance, was prepared by using tungsten foil as a substrate in this study. It was found that the WO3 discoloration layer, having a monoclinic phase crystalline structure made of 600 °C calcined, had optimum charge transmission performance with PADA gel polymer electrolyte. Ionic conductivity of PADA gel polymer electrolyte was 2.3 × 10−3 S cm−1 at −20 °C, and it was possible to help Li+ to implement embedding and extraction from WO3 even in low-temperature conditions. The colored time (tc) and the bleached time (tb) of the electrochromic device were 15 s and 26 s, and it showed yellowish-brown in the colored state and navy blue in the bleached state. The ECD (WO3-600) exhibited good cycle stability reach at least 150 times.
Application of Polymers for Chemical Enhanced Oil Recovery: A Review
Authors: Gbadamosi Afeez , Patil Shirish , Kamal Muhammad Shahzad , Adewunmi Ahmad A. , Yusuff Adeyinka S. , Agi Augustine , Oseh Jeffrey
Published: April 2022

Polymers play a significant role in enhanced oil recovery (EOR) due to their viscoelastic properties and macromolecular structure. Herein, the mechanisms of the application of polymeric materials for enhanced oil recovery are elucidated. Subsequently, the polymer types used for EOR, namely synthetic polymers and natural polymers (biopolymers), and their properties are discussed. Moreover, the numerous applications for EOR such as polymer flooding, polymer foam flooding, alkali–polymer flooding, surfactant–polymer flooding, alkali–surfactant–polymer flooding, and polymeric nanofluid flooding are appraised and evaluated. Most of the polymers exhibit pseudoplastic behavior in the presence of shear forces. The biopolymers exhibit better salt tolerance and thermal stability but are susceptible to plugging and biodegradation. As for associative synthetic polyacrylamide, several complexities are involved in unlocking its full potential. Hence, hydrolyzed polyacrylamide remains the most coveted polymer for field application of polymer floods. Finally, alkali–surfactant–polymer flooding shows good efficiency at pilot and field scales, while a recently devised polymeric nanofluid shows good potential for field application of polymer flooding for EOR.
Synthesis of Novel Ultraviolet Absorbers and Preparation and Field Application of Anti-Ultraviolet Aging PBAT/UVA Films
Authors: Qiao Run-Meng , Zhao Chi-Peng , Liu Jia-Lei , Zhang Mao-Lin , He Wen-Qing
Published: April 2022

Poly-(butylene adipate-co-terephthalate) (PBAT) has become one of the most prevalent biodegradable plastic film materials owing to its good degradability, mechanical properties, and processability. However, the degradation time of this material was too fast and the functional period was short, which limited its application. Herein, three new tropolone-based UV absorbers (UVA-1C, UVA-4C and UVA-6C) were rationally designed and blended into PBAT. The PBAT/UVA films that formed were used against UV aging and prolonged the functional period of PBAT film. The three new absorbers were synthesized by bridging two tropolones using three different organic chains with different flexibility. Among them, the UVA-6C showed the strongest UV absorbance at around 238 nm and 320 nm. Consequently, the PBAT/UVA-6C film showed an extended validity period of 240 h in the Xenon lamp aging machine and a prolonged functional period of 8 d during the field application test when compared to pure PBAT. More importantly, a 7.8% increase in the maize yield was obtained under PBAT/UVA-6C film relative to pure PBAT film. Obviously, the novel prepared UVA-6C compound is a good candidate for UV absorption in PBAT, which makes PBAT/UVA-6C film more advantageous over pure PBAT in practical applications as biodegradable agricultural film.
Cyclodextrin-Oligocaprolactone Derivatives—Synthesis and Advanced Structural Characterization by MALDI Mass Spectrometry
Authors: Peptu Cristian , Blaj Diana-Andreea , Balan-Porcarasu Mihaela , Rydz Joanna
Published: April 2022

Cyclodextrins have previously been proven to be active in the catalysis of cyclic ester ring-opening reactions, hypothetically in a similar way to lipase-catalyzed reactions. However, the way they act remains unclear. Here, we focus on β-cyclodextrin’s involvement in the synthesis and characterization of β-cyclodextrin-oligocaprolactone (CDCL) products obtained via the organo-catalyzed ring-opening of ε-caprolactone. Previously, bulk or supercritical carbon dioxide polymerizations has led to inhomogeneous products. Our approach consists of solution polymerization (dimethyl sulfoxide and dimethylformamide) to obtain homogeneous CDCL derivatives with four monomer units on average. Oligomerization kinetics, performed by a matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) optimized method in tandem with 1H NMR, revealed that monomer conversion occurs in two stages: first, the monomer is rapidly attached to the secondary OH groups of β-cyclodextrin and, secondly, the monomer conversion is slower with attachment to the primary OH groups. MALDI MS was further employed for the measurement of the ring-opening kinetics to establish the influence of the solvents as well as the effect of organocatalysts (4-dimethylaminopyridine and (–)-sparteine). Additionally, the mass spectrometry structural evaluation was further enhanced by fragmentation studies which confirmed the attachment of oligoesters to the cyclodextrin and the cleavage of dimethylformamide amide bonds during the ring-opening process.
Analysis of Internal Flow and Wear Characteristics of Binary Mixture Particles in Centrifugal Pump Based on CFD-DEM
Authors: Wang Yanping , He Tielin , Ding Qiangmin , Gao Panlong , Tao Ruilin , Zhu Zuchao
Published: April 2022

Solid-liquid two-phase flow centrifugal pumps are widely used in many fields closely related to economic development, such as energy exploitation, and the petrochemical industry. Many scholars have studied the influence of solid particles with different parameters on the transportation performance of centrifugal pumps but have mainly focused on the study of low-concentration single-component particles, and the research on the transportation of high-concentration binary mixture particles in centrifugal pumps is insufficient. In this paper, two kinds of glass beads (0.4 mm and 2 mm) were mixed as a solid phase medium, representing small particles and large particles, respectively. The effects of a high concentration (Cv = 10%) of binary mixture particles on the transport and wear characteristics of a solid-liquid centrifugal pump were analyzed by simulation and experiment. Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) and Archard wear model were used for simulation, realized by Fluent software and EDEM software. The results show that the large particles have a greater effect on the performance decline than the small particles, and the increase of the proportion of large particles has a greater effect on the efficiency decline than the head decline. The wear degree of the flow channel in the pump changes obviously with the particle ratio, and the overall wear is small when the particle ratio is 1:2.
Latest Advances in Waste Plastic Pyrolytic Catalysis
Authors: Yansaneh Osman Y. , Zein Sharif H.
Published: April 2022

With the increase in demand for plastic use, waste plastic (WP) management remains a challenge in the contemporary world due to the lack of sustainable efforts to tackle it. The increment in WPs is proportional to man’s demand and use of plastics, and these come along with environmental challenges. This increase in WPs, and the resulting environmental consequences are mainly due to the characteristic biodegradation properties of plastics. Landfilling, pollution, groundwater contamination, incineration, and blockage of drainages are common environmental challenges associated with WPs. The bulk of these WPs constitutes polyethene (PE), polyethene terephthalate (PET) and polystyrene (PS). Pyrolysis is an eco-friendly thermo-chemical waste plastic treatment solution for valuable product recovery, preferred over landfilling and incineration solutions. In this extensive review, a critical investigation on waste plastic catalytic pyrolysis (WPCP) is performed, including catalyst and non-catalyst applications to sustainably tackle WP management. Current catalysis techniques are revealed, and some comparisons are made where necessary. Common pyrolytic products and common shortcomings and errors related to WP catalysis were also identified. The benefits of catalysts and their applications to augment and optimise thermal pyrolysis are emphasised. With all these findings, and more, this paper provides reassurance on the significance of catalysis to industrial-scale applications and products and supports related WPCP research work concerning the environment and other beneficiaries.
A Combined Model Based on the Social Cognitive Optimization Algorithm for Wind Speed Forecasting
Authors: He Zhaoshuang , Chen Yanhua , Xu Jian
Published: April 2022

The use of wind power generation can reduce the pollution in the environment and solve the problem of power shortages on offshore islands, grasslands, pastoral areas, mountain areas, and highlands. Wind speed forecasting plays a significant role in wind farms. It can improve economic and social benefits and make an operation schedule for wind turbines on large wind farms. This paper proposes a combined model based on the existing artificial neural network algorithms for wind speed forecasting at different heights. We first use the wavelet threshold method with the original wind speed dataset for noise reduction. After that, the three artificial neural networks, extreme learning machine (ELM), Elman neural network, and Long Short-term Memory (LSTM) neural network, are applied for wind speed forecasting. In addition, the variance reciprocal method and social cognitive optimization (SCO) algorithm are used to optimize the weight coefficients of the combined model. In order to evaluate the forecasting performance of the combined model, we select wind speed data at three heights (20 m, 50 m and 80 m) at the National Wind Technology Center M2 Tower. The experimental results show that the forecasting performance of the combined model is better than the single model, and it has a good forecasting performance for the wind speed at different heights.
Transformations of Religiosity during the SARS-CoV-2 Pandemic—On the Example of Catholic Religious Practices of Polish Students
Authors: Dobosz Dagmara , Gierczyk Marcin , Janiak Agnieszka , Piasecki Dariusz , Rajba Beata
Published: April 2022

This paper attempts to identify the changes in religiosity among Catholic practitioners in Poland that occurred during the COVID-19 pandemic, based on the changes in the realization of religious practices by students (N = 354). A questionnaire prepared by the authors was used for the study. We sought to answer the question of the extent to which the socio-demographic characteristics of the subjects, a history of COVID-19, and the death of a family member due to SARS-CoV-2 infection differentiated the subjects’ opinions about religiosity and their undertaking of religious practices. The paper also addresses the issue of media-facilitated religious practices. The study showed that the frequency of religious practices was influenced by the perceived religiosity of the family, the religiosity of the respondent, and the declaration concerning the belief in God. The same factors most often significantly differentiated respondents’ opinions on COVID-19. No relationship was confirmed between having COVID-19 and subjects’ beliefs about the pandemic or frequency of religious practice. Among the respondents, the pandemic did not intensify the practice of religion. In the face of danger, respondents did not turn to God; there was no revitalization of religion. The situation of limiting the physical experience communion of the Church was treated not as an acute undersupply but as an opportunity or a pretext to abandon the practice of religion.
Study and Evaluation of Surface Water Resources Affected by Ancient and Illegal Mining in the Upper Part of the Milluni Micro-Basin, Bolivia
Authors: Alvizuri-Tintaya Paola Andrea , Rios-Ruiz Marco , Lora-Garcia Jaime , Torregrosa-López Juan Ignacio , Lo-Iacono-Ferreira Vanesa G.
Published: April 2022

One of the factors with the most significant impact due to pollution caused by mining activities is water. Surface water resources are limited, and in many cases, they are the primary water source for consumption; thus, its quality is a fundamental subject of study. The traditional way of studying water quality is to measure parameters and compare the results with tables of values established in the regulations. The quality of drinking water is characterized and controlled. However, this traditional comparison method may be subjective and insufficient to classify water quality as safe. Therefore, it is necessary to develop and complement the conventional monitoring, linking physicochemical analysis with remote perception. The different variables analyzed can be integrated and result in much more complete water quality indices, achieving the evolution of the monitoring programs of the water quality of the surface bodies. This research combines remote sensing with traditional monitoring to obtain a more robust and affordable indicator, resulting in a study of the central water bodies of Milluni. The main finding—the alarming contamination in the Milluni Chico and Milluni Grande lagoons—provides more accurate information to decision-makers to improve water management in Bolivia.
Assessing the Potential of Long, Multi-Temporal SAR Interferometry Time Series for Slope Instability Monitoring: Two Case Studies in Southern Italy
Authors: Bovenga Fabio , Argentiero Ilenia , Refice Alberto , Nutricato Raffaele , Nitti Davide O. , Pasquariello Guido , Spilotro Giuseppe
Published: April 2022

Multi-temporal SAR interferometry (MTInSAR), by providing both mean displacement maps and displacement time series over coherent objects on the Earth’s surface, allows analyzing wide areas, identifying ground displacements, and studying the phenomenon evolution at a long time scale. This technique has also been proven to be very useful for detecting and monitoring slope instabilities. For this type of hazard, detection of velocity variations over short time intervals should be useful for early warning of damaging events. In this work, we present the results obtained by using both COSMO-SkyMed (CSK) and Sentinel-1 (S1) data for investigating the ground stability of two hilly villages located in the Southern Italian Apennines (Basilicata region), namely the towns of Montescaglioso and Pomarico. In these two municipalities, landslides occurred in the recent past (in Montescaglioso in 2013) and more recently (in Pomarico in 2019), causing damage to houses, commercial buildings, and infrastructures. SAR datasets acquired by CSK and S1 from both ascending and descending orbits were processed using the SPINUA MTInSAR algorithm. Mean velocity maps and displacement time series were analyzed, also by means of innovative ad hoc procedures, looking, in particular, for non-linear trends. Results evidenced the presence of nonlinear displacements in correspondence of some key infrastructures. In particular, the analysis of accelerations and decelerations of PS objects corresponding to structures affected by recent stabilization measures helps to shed new light in relation to known events that occurred in the area of interest.
Concurrent Climate Extremes and Impacts on Ecosystems in Southwest China
Authors: Liu Lulu , Jiang Yuan , Gao Jiangbo , Feng Aiqing , Jiao Kewei , Wu Shaohong , Zuo Liyuan , Li Yuqing , Yan Rui
Published: April 2022

Global warming and its associated changes in temperature and precipitation have significantly affected the ecosystem in Southwest China, yet studies that integrate temperature and precipitation changes are inadequate for quantitatively assessing the impacts of extreme events on ecosystems. In this study, the return period of concurrent climate extremes characterized by precipitation deficit and extreme temperature and the spatial and temporal dynamic patterns of their impacts on ecosystems were assessed by using high-precision temperature and precipitation data, as well as NDVI and NPP data collected for the 1985–2015 period. The results show that the 2009 concurrent event had a return period of about 200 years. The return periods of individual climate factors are significantly overestimated or underestimated. Concurrent events significantly reduced the spring and annual Normalized Difference Vegetation Index (NDVI) and net primary productivity (NPP) in Southwest China. The magnitude of the reduction in vegetation greenness and productivity increased with the intensity of concurrent events. Concurrent events beginning in autumn 2009 reduced spring NDVI and NPP by 8.8% and 23%, and annual NDVI and NPP by 2.23% and 7.22%, respectively. Under future climate scenarios, the return period of concurrent events could be significantly shortened, which would have a more severe impact on regional ecosystems.