bluuebunny/crossref_metadata_2025 huggingface dataset:
Bismuth Oxyhalides for NOx Degradation under Visible Light: The Role of the Chloride Precursor
Authors: Tessore Francesca , Galli Federico , Schieppati Dalma , Boffito Daria C. , Di Michele Alessandro , Demartin Francesco , Cerrato Giuseppina , Bianchi Claudia L.
Published: January 2021

Photocatalysis is a green technology for tackling water and air contamination. A valid alternative to the most exploited photocatalytic material, TiO2, is bismuth oxyhalides, which feature a wider bandgap energy range and use visible radiation to attain photoexcitation. Moreover, their layered structure favors the separation of photogenerated electron–hole pairs, with an enhancement in photocatalytic activity. Controlled doping of bismuth oxyhalides with metallic bismuth nanoparticles allows for further boosting of the performance of the material. In the present work, we synthesized Y%Bi-doped BiO(Cl0.875Br0.125) (Y = 0.85, 1, 2, 10) photocatalysts, using cetyltrimethylammonium bromide as the bromide source and varying the chloride source to assess the impact that both length and branching of the hydrocarbon chain might have on the framing and layering of the material. A change in the amount of the reducing agent NaBH4 allowed tuning of the percentage of metallic bismuth. After a thorough characterization (XRPD, SEM, TEM, UV-DRS, XPS), the photocatalytic activity of the catalysts was tested in the degradation of NOx under visible light, reaching a remarkable 53% conversion after 3 h of illumination for the material prepared using cetylpyridinium chloride.
Promoting Photoelectrochemical Water Oxidation on Ti-Doped Fe2O3 Nanowires Photoanode by O2 Plasma Treatment
Authors: Li Chuang , Wang Dan , Gu Jiangli , Liu Yichun , Zhang Xintong
Published: January 2021

Surface electron traps on semiconductor photoanodes mediate surface recombination and deteriorate the photoelectrochemical (PEC) water oxidation performance of the photoanode. Developing convenient methods to reduce surface electron traps is therefore essential for high efficiency PEC water oxidation on semiconductor photoanodes, particularly for nanostructured photoanodes with large surface area. Herein, we employ a O2 plasma treatment to boost the PEC water oxidation performance of Ti-doped Fe2O3 (Ti-Fe2O3) nanowires photoanodes, aiming to reduce surface oxygen vacancies, the dominant electron traps on Ti-Fe2O3 surface. X-ray diffraction (XRD), scanning electron microscopy and spectroscopic analyses show that the oxygen plasma treatment changes the structural, morphological and optical properties negligibly, but it does reduce the content of surface oxygen vacancies, as estimated from O1s X-ray photoelectron spectroscopy spectra. An optimal O2 plasma treatment (200 W, 70 s) increases the photocurrent density of the Ti-Fe2O3 nanowire photoanode to 2.14 mA·cm−2 (1.23 V vs. RHE) under air mass 1.5G simulated solar light, which is 1.95 times higher than the pristine Ti-Fe2O3 nanowire photoanode. The surface hole transfer efficiency is also improved by 1.66 times due to the reduced surface recombination. The work suggests that O2 plasma treatment is a convenient but effective method to boost the PEC water oxidation performance of Ti-Fe2O3 photoanode and might be applicable to other semiconducting oxide photoanodes for high efficiency PEC water splitting.
Kinetic Modeling of Solketal Synthesis from Glycerol and Acetone Catalyzed by an Iron(III) Complex
Authors: Taddeo Francesco , Esposito Roberto , Russo Vincenzo , Di Serio Martino
Published: January 2021

In the last few years, the depletion of the fossil sources and their negative effect on the environment has led to find new alternatives; among these, biodiesel is considered one of the most promising for this purpose. Biodiesel can be produced from the transesterification of vegetable oils or animal fats, obtaining glycerol as a by-product. Glycerol can be used in different processes and one of the most interesting is the condensation with acetone to produce solketal. Among its applications, plasticizers, solvents, and pharmaceutical formulations are the most common. In this work, the attention was focused on the reaction between glycerol and acetone to give solketal promoted by an iron(III) complex. The reaction mechanism was hypothesized, and the kinetics was studied in a batch reactor. Finally, the thermodynamic and kinetic parameters were determined with a reliable model investigating the phenomena that occurred in the reaction network.
Synergism between Cutinase and Pectinase in the Hydrolysis of Cotton Fibers’ Cuticle
Authors: Degani Ofir
Published: January 2021

Scouring is one of the initial steps in the processing of natural textile fibers (e.g., cotton), performed to remove waxes and pectins, together with spinning oils and other impurities of the plant cell cuticle. Traditional chemical bleaching with boiling NaOH led to harsh removal of the entire fabric’s cuticle waxy layer accompanied by an unwanted alkaline waste. Extracellular lytic enzymes such as lipases, cellulases and pectinases play an essential role in host plant-pathogen interactions. They degrade the plant cuticle and tissue and enable pathogen invasion. Such enzymes, specifically cutinase and pectinase, have been considered potential bio-scouring agents to degrade the cotton fabric cuticle’s outer layer at low temperature and alleviate environmental pollution. In this work, the combined effect of cutinase, pectin lyase, or polygalacturonase on the scouring of cotton fabrics was studied using evaporative light-scattering reverse-phase HPLC and GC-MS analysis of the reaction components, and measuring changes in the cotton fabrics’ properties. The traditional method of cotton fabrics’ scouring with NaOH resulted in decreased pectin content and increased cellulose fibers accessibility, evaluated by specific staining. Treating the cotton fibers’ cuticle with cutinase led to the acidification of the reaction mixture, a decrease in enzyme-specific activity, and elevation in hexadecanoic acid and octadecanoic acids in the reaction fluid. These two saturated fatty acids are the main wax constituents of raw cotton fabrics, identified using GC-MS after dichloromethane reflux overnight. Treating cotton fabrics with each of the three enzymes, cutinase, pectin lyase, or polygalacturonase, increased their pectin removal, as measured by high concentrations of D-galacturonic acid and other pectin constituents in the reaction fluid. A synergistic effect was found in the combined treatment of cutinase and pectin lyase in the hydrolysis of the cotton fibers’ cuticle. This effect was expressed in high water absorbency of the treated fibers, increased fabric weight loss and sharp elevation of a cutin and pectin monomer’s related peaks (retention time [RT] = 4.1 min and 2.9, 4.5 min, respectively). A model was suggested for the synergistic action between cutinase and pectin lyase. It assumes that the cuticle’s digestion by cutinase results in the enlargement and formation of outer layer micropores, which enables the rapid penetration of pectinase into the inner pectin layer.
The Role of Glycerol and Its Derivatives in the Biochemistry of Living Organisms, and Their Prebiotic Origin and Significance in the Evolution of Life
Authors: Gull Maheen , Pasek Matthew A.
Published: January 2021

The emergence and evolution of prebiotic biomolecules on the early Earth remain a question that is considered crucial to understanding the chemistry of the origin of life. Amongst prebiotic molecules, glycerol is significant due to its ubiquity in biochemistry. In this review, we discuss the significance of glycerol and its various derivatives in biochemistry, their plausible roles in the origin and evolution of early cell membranes, and significance in the biochemistry of extremophiles, followed by their prebiotic origin on the early Earth and associated catalytic processes that led to the origin of these compounds. We also discuss various scenarios for the prebiotic syntheses of glycerol and its derivates and evaluate these to determine their relevance to early Earth biochemistry and geochemistry, and recapitulate the utilization of various minerals (including clays), condensation agents, and solvents that could have led to the successful prebiotic genesis of these biomolecules. Furthermore, important prebiotic events such as meteoritic delivery and prebiotic synthesis reactions under astrophysical conditions are also discussed. Finally, we have also highlighted some novel features of glycerol, including glycerol nucleic acid (GNA), in the origin and evolution of the life.
Influence of the Reduction Temperature and the Nature of the Support on the Performance of Zirconia and Alumina-Supported Pt Catalysts for n-Dodecane Hydroisomerization
Authors: García-Pérez Diana , Alvarez-Galvan Maria Consuelo , Campos-Martin Jose M. , Fierro Jose L. G.
Published: January 2021

Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.
Metabolomics and DNA-Based Authentication of Two Traditional Asian Medicinal and Aromatic Species of Salvia subg. Perovskia
Authors: Bielecka Monika , Pencakowski Bartosz , Stafiniak Marta , Jakubowski Klemens , Rahimmalek Mehdi , Gharibi Shima , Matkowski Adam , Ślusarczyk Sylwester
Published: January 2021

Subgenus Perovskia of the extended genus of Salvia comprises several Central Asian medicinal and aromatic species, of which S. yangii and S. abrotanoides are the most widespread. These plants are cultivated in Europe as robust ornamentals, and several cultivars are available. However, their medicinal potential remains underutilized because of limited information about their phytochemical and genetic diversity. Thus, we combined an ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOF-MS) based metabolomics with DNA barcoding approach based on trnH-psbA and ITS2 barcodes to clarify the relationships between these two taxa. Metabolomic analysis demonstrated that aerial parts are more similar than roots and none of the major compounds stand out as distinct. Sugiol in S. yangii leaves and carnosic acid quinone in S. abrotanoides were mostly responsible for their chemical differentiation, whereas in roots the distinction was supported by the presence of five norditerpenoids in S. yangii and two flavonoids and one norditerpenoid in S. abrotanoides. To verify the metabolomics-based differentiation, we performed DNA authentication that revealed S. yangii and S. abrotanoides to be very closely related but separate species. We demonstrated that DNA barcoding coupled with parallel LC-MS profiling constitutes a powerful tool in identification of taxonomically close Salvia species.
microRNAs as Early Biomarkers of Alzheimer’s Disease: A Synaptic Perspective
Authors: Siedlecki-Wullich Dolores , Miñano-Molina Alfredo J. , Rodríguez-Álvarez José
Published: January 2021

Pathogenic processes underlying Alzheimer’s disease (AD) affect synaptic function from initial asymptomatic stages, long time before the onset of cognitive decline and neurodegeneration. Therefore, reliable biomarkers enabling early AD diagnosis and prognosis are needed to maximize the time window for therapeutic interventions. MicroRNAs (miRNAs) have recently emerged as promising cost-effective and non-invasive biomarkers for AD, since they can be readily detected in different biofluids, including cerebrospinal fluid (CSF) and blood. Moreover, a growing body of evidence indicates that miRNAs regulate synaptic homeostasis and plasticity processes, suggesting that they may be involved in early synaptic dysfunction during AD. Here, we review the current literature supporting a role of miRNAs during early synaptic deficits in AD, including recent studies evaluating their potential as AD biomarkers. Besides targeting genes related to Aβ and tau metabolism, several miRNAs also regulate synaptic-related proteins and transcription factors implicated in early synaptic deficits during AD. Furthermore, individual miRNAs and molecular signatures have been found to distinguish between prodromal AD and healthy controls. Overall, these studies highlight the relevance of considering synaptic-related miRNAs as potential biomarkers of early AD stages. However, further validation studies in large cohorts, including longitudinal studies, as well as implementation of standardized protocols, are needed to establish miRNA-based biomarkers as reliable diagnostic and prognostic tools.
Stick around: Cell–Cell Adhesion Molecules during Neocortical Development
Authors: de Agustín-Durán David , Mateos-White Isabel , Fabra-Beser Jaime , Gil-Sanz Cristina
Published: January 2021

The neocortex is an exquisitely organized structure achieved through complex cellular processes from the generation of neural cells to their integration into cortical circuits after complex migration processes. During this long journey, neural cells need to establish and release adhesive interactions through cell surface receptors known as cell adhesion molecules (CAMs). Several types of CAMs have been described regulating different aspects of neurodevelopment. Whereas some of them mediate interactions with the extracellular matrix, others allow contact with additional cells. In this review, we will focus on the role of two important families of cell–cell adhesion molecules (C-CAMs), classical cadherins and nectins, as well as in their effectors, in the control of fundamental processes related with corticogenesis, with special attention in the cooperative actions among the two families of C-CAMs.
Herpesvirus Antibodies, Vitamin D and Short-Chain Fatty Acids: Their Correlation with Cell Subsets in Multiple Sclerosis Patients and Healthy Controls
Authors: Dominguez-Mozo Maria Inmaculada , Perez-Perez Silvia , Villarrubia Noelia , Costa-Frossard Lucienne , Fernandez-Velasco Jose Ignacio , Ortega-Madueño Isabel , Garcia-Martinez Maria Angel , Garcia-Calvo Estefania , Estevez Hector , Luque Garcia Jose Luis , Torrejon Maria Josefa , Arroyo Rafael , Villar Luisa Maria , Alvarez-Lafuente Roberto
Published: January 2021

Although the etiology of multiple sclerosis (MS) is still unknown, it is commonly accepted that environmental factors could contribute to the disease. The objective of this study was to analyze the humoral response to Epstein-Barr virus, human herpesvirus 6A/B and cytomegalovirus, and the levels of 25-hydroxyvitamin D (25(OH)D) and the three main short-chain fatty acids (SCFA), propionate (PA), butyrate (BA) and acetate (AA), in MS patients and healthy controls (HC) to understand how they could contribute to the pathogenesis of the disease. With this purpose, we analyzed the correlations among them and with different clinical variables and a wide panel of cell subsets. We found statistically significant differences for most of the environmental factors analyzed when we compared MS patients and HC, supporting their possible involvement in the disease. The strongest correlations with the clinical variables and the cell subsets analyzed were found for 25(OH)D and SCFAs levels. A correlation was also found between 25(OH)D and PA/AA ratio, and the interaction between these factors negatively correlated with interleukin 17 (IL-17)-producing CD4+ and CD8+ T cells in untreated MS patients. Therapies that simultaneously increase vitamin D levels and modify the proportion of SCFA could be evaluated in the future.
Role of Annexin A1 in NLRP3 Inflammasome Activation in Murine Neutrophils
Authors: Sanches José Marcos , Correia-Silva Rebeca D. , Duarte Gustavo H. B. , Fernandes Anna Maria A. P. , Sánchez-Vinces Salvador , Carvalho Patrícia O. , Oliani Sonia M. , Bortoluci Karina R. , Moreira Vanessa , Gil Cristiane D.
Published: January 2021

This study evaluated the role of endogenous and exogenous annexin A1 (AnxA1) in the activation of the NLRP3 inflammasome in isolated peritoneal neutrophils. C57BL/6 wild-type (WT) and AnxA1 knockout mice (AnxA1-/-) received 0.3% carrageenan intraperitoneally and, after 3 h, the peritoneal exudate was collected. WT and AnxA1-/- neutrophils were then stimulated with lipopolysaccharide, followed by the NLRP3 agonists nigericin or ATP. To determine the exogenous effect of AnxA1, the neutrophils were pretreated with the AnxA1-derived peptide Ac2-26 followed by the NLRP3 agonists. Ac2-26 administration reduced NLRP3-derived IL-1β production by WT neutrophils after nigericin and ATP stimulation. However, IL-1β release was impaired in AnxA1-/- neutrophils stimulated by both agonists, and there was no further impairment in IL-1β release with Ac2-26 treatment before stimulation. Despite this, ATP- and nigericin-stimulated AnxA1-/- neutrophils had increased levels of cleaved caspase-1. The lipidomics of supernatants from nigericin-stimulated WT and AnxA1-/- neutrophils showed potential lipid biomarkers of cell stress and activation, including specific sphingolipids and glycerophospholipids. AnxA1 peptidomimetic treatment also increased the concentration of phosphatidylserines and oxidized phosphocholines, which are lipid biomarkers related to the inflammatory resolution pathway. Together, our results indicate that exogenous AnxA1 negatively regulates NLRP3-derived IL-1β production by neutrophils, while endogenous AnxA1 is required for the activation of the NLRP3 machinery.
MG53, A Tissue Repair Protein with Broad Applications in Regenerative Medicine
Authors: Li Zhongguang , Wang Liyang , Yue Huimin , Whitson Bryan A. , Haggard Erin , Xu Xuehong , Ma Jianjie
Published: January 2021

Under natural conditions, injured cells can be repaired rapidly through inherent biological processes. However, in the case of diabetes, cardiovascular disease, muscular dystrophy, and other degenerative conditions, the natural repair process is impaired. Repair of injury to the cell membrane is an important aspect of physiology. Inadequate membrane repair function is implicated in the pathophysiology of many human disorders. Recent studies show that Mitsugumin 53 (MG53), a TRIM family protein, plays a key role in repairing cell membrane damage and facilitating tissue regeneration. Clarifying the role of MG53 and its molecular mechanism are important for the application of MG53 in regenerative medicine. In this review, we analyze current research dissecting MG53′s function in cell membrane repair and tissue regeneration, and highlight the development of recombinant human MG53 protein as a potential therapeutic agent to repair multiple-organ injuries.
Arginine Methylation in Brain Tumors: Tumor Biology and Therapeutic Strategies
Authors: Bryant Jean-Paul , Heiss John , Banasavadi-Siddegowda Yeshavanth Kumar
Published: January 2021

Protein arginine methylation is a common post-translational modification that plays a pivotal role in cellular regulation. Protein arginine methyltransferases (PRMTs) catalyze the modification of target proteins by adding methyl groups to the guanidino nitrogen atoms of arginine residues. Protein arginine methylation takes part in epigenetic and cellular regulation and has been linked to neurodegenerative diseases, metabolic diseases, and tumor progression. Aberrant expression of PRMTs is associated with the development of brain tumors such as glioblastoma and medulloblastoma. Identifying PRMTs as plausible contributors to tumorigenesis has led to preclinical and clinical investigations of PRMT inhibitors for glioblastoma and medulloblastoma therapy. In this review, we discuss the role of arginine methylation in cancer biology and provide an update on the use of small molecule inhibitors of PRMTs to treat glioblastoma, medulloblastoma, and other cancers.
Interactions between Cellulose and (1,3;1,4)-β-glucans and Arabinoxylans in the Regenerating Wall of Suspension Culture Cells of the Ryegrass Lolium multiflorum
Authors: van de Meene Allison , McAloney Lauren , Wilson Sarah , Zhou JiZhi , Zeng Wei , McMillan Paul , Bacic Antony , Doblin Monika
Published: January 2021

Plant cell walls (PCWs) form the outer barrier of cells that give the plant strength and directly interact with the environment and other cells in the plant. PCWs are composed of several polysaccharides, of which cellulose forms the main fibrillar network. Enmeshed between these fibrils of cellulose are non-cellulosic polysaccharides (NCPs), pectins, and proteins. This study investigates the sequence, timing, patterning, and architecture of cell wall polysaccharide regeneration in suspension culture cells (SCC) of the grass species Lolium multiflorum (Lolium). Confocal, superresolution, and electron microscopies were used in combination with cytochemical labeling to investigate polysaccharide deposition in SCC after protoplasting. Cellulose was the first polysaccharide observed, followed shortly thereafter by (1,3;1,4)-β-glucan, which is also known as mixed-linkage glucan (MLG), arabinoxylan (AX), and callose. Cellulose formed fibrils with AX and produced a filamentous-like network, whereas MLG formed punctate patches. Using colocalization analysis, cellulose and AX were shown to interact during early stages of wall generation, but this interaction reduced over time as the wall matured. AX and MLG interactions increased slightly over time, but cellulose and MLG were not seen to interact. Callose initially formed patches that were randomly positioned on the protoplast surface. There was no consistency in size or location over time. The architecture observed via superresolution microscopy showed similarities to the biophysical maps produced using atomic force microscopy and can give insight into the role of polysaccharides in PCWs.
Central Regulation of Metabolism by Growth Hormone
Authors: Donato Jose , Wasinski Frederick , Furigo Isadora C. , Metzger Martin , Frazão Renata
Published: January 2021

Growth hormone (GH) is secreted by the pituitary gland, and in addition to its classical functions of regulating height, protein synthesis, tissue growth, and cell proliferation, GH exerts profound effects on metabolism. In this regard, GH stimulates lipolysis in white adipose tissue and antagonizes insulin’s effects on glycemic control. During the last decade, a wide distribution of GH-responsive neurons were identified in numerous brain areas, especially in hypothalamic nuclei, that control metabolism. The specific role of GH action in different neuronal populations is now starting to be uncovered, and so far, it indicates that the brain is an important target of GH for the regulation of food intake, energy expenditure, and glycemia and neuroendocrine changes, particularly in response to different forms of metabolic stress such as glucoprivation, food restriction, and physical exercise. The objective of the present review is to summarize the current knowledge about the potential role of GH action in the brain for the regulation of different metabolic aspects. The findings gathered here allow us to suggest that GH represents a hormonal factor that conveys homeostatic information to the brain to produce metabolic adjustments in order to promote energy homeostasis.
Calreticulin—Multifunctional Chaperone in Immunogenic Cell Death: Potential Significance as a Prognostic Biomarker in Ovarian Cancer Patients
Authors: Kielbik Michal , Szulc-Kielbik Izabela , Klink Magdalena
Published: January 2021

Immunogenic cell death (ICD) is a type of death, which has the hallmarks of necroptosis and apoptosis, and is best characterized in malignant diseases. Chemotherapeutics, radiotherapy and photodynamic therapy induce intracellular stress response pathways in tumor cells, leading to a secretion of various factors belonging to a family of damage-associated molecular patterns molecules, capable of inducing the adaptive immune response. One of them is calreticulin (CRT), an endoplasmic reticulum-associated chaperone. Its presence on the surface of dying tumor cells serves as an “eat me” signal for antigen presenting cells (APC). Engulfment of tumor cells by APCs results in the presentation of tumor’s antigens to cytotoxic T-cells and production of cytokines/chemokines, which activate immune cells responsible for tumor cells killing. Thus, the development of ICD and the expression of CRT can help standard therapy to eradicate tumor cells. Here, we review the physiological functions of CRT and its involvement in the ICD appearance in malignant disease. Moreover, we also focus on the ability of various anti-cancer drugs to induce expression of surface CRT on ovarian cancer cells. The second aim of this work is to discuss and summarize the prognostic/predictive value of CRT in ovarian cancer patients.
Unconventional Materials Processing Using Spark Plasma Sintering
Authors: Nisar Ambreen , Zhang Cheng , Boesl Benjamin , Agarwal Arvind
Published: January 2021

Spark plasma sintering (SPS) has gained recognition in the last 20 years for its rapid densification of hard-to-sinter conventional and advanced materials, including metals, ceramics, polymers, and composites. Herein, we describe the unconventional usages of the SPS technique developed in the field. The potential of various new modifications in the SPS technique, from pressureless to the integration of a novel gas quenching system to extrusion, has led to SPS’ evolution into a completely new manufacturing tool. The SPS technique’s modifications have broadened its usability from merely a densification tool to the fabrication of complex-shaped components, advanced functional materials, functionally gradient materials, interconnected materials, and porous filter materials for real-life applications. The broader application achieved by modification of the SPS technique can provide an alternative to conventional powder metallurgy methods as a scalable manufacturing process. The future challenges and opportunities in this emerging research field have also been identified and presented.
Development of Gas-Liquid Slug Flow Measurement Using Continuous-Wave Doppler Ultrasound and Bandpass Power Spectral Density
Authors: Nnabuife Somtochukwu Godfrey , Sharma Prafull , Iyore Aburime Ebuwa , Lokidor Pauline Long’or , Bello Abdulrauf
Published: January 2021

This paper addresses the issues of slug detection and characterization in air-water two-phase flow in a vertical pipeline. A novel non-invasive measurement technique using continuous-wave Doppler ultrasound (CWDU) and bandpass power spectral density (BPSD) is proposed for multiphase flow applications and compared with the more established gamma-ray densitometry measurement. In this work, analysis using time-frequency analysis of the CWDU is performed to infer the applicability of the BPSD method for observing the slug front and trailing bubbles in a multiphase flow. The CWDU used a piezo transmitter/receiver pair with an ultrasonic frequency of 500 kHz. Signal processing on the demodulated signal of Doppler frequency was done using the Butterworth bandpass filter on the power spectral density which reveals slugs from background bubbles. The experiments were carried out in the 2” vertical pipeline-riser at the process system engineering laboratory at Cranfield University. The 2-inch test facility used in this experiment is made up of a 54.8 mm internal diameter and 10.5 m high vertical riser connected to a 40 m long horizontal pipeline. Taylor bubbles were generated using a quick-closing air valve placed at the bottom of the riser underwater flow, with rates of 0.5 litres/s, 2 litres/s, and 4 litres/s. The CWDU spectrum of the measured signal along with the BPSD method is shown to describe the distinctive nature of the slugs.
Nursing Perspective of the Humanized Care of the Neonate and Family: A Systematic Review
Authors: Gómez-Cantarino Sagrario , García-Valdivieso Inmaculada , Dios-Aguado Mercedes , Yáñez-Araque Benito , Gallego Brigida Molina , Moncunill-Martínez Eva
Published: January 2021

This systematic review aims to determine the extent to which published research articles show the perspective of health professionals in neonatal intensive care units (NICU), as facilitators of family empowerment. Studies conducted between 2013 and 2020 were retrieved from five databases (PubMed, Cochrane, CINHAL, Scopus, and Google Scholar). The search was carried out from January to October 2020. A total of 40 articles were used, of which 13 studies (quantitative and qualitative) were included in this systematic review. Its methodological quality was assessed using the mixed methods assessment tool (MMAT). In these, the opinions and perspectives of professionals on the permanence and participation of parents were valued. In addition, the training, experiences, and educational needs of nursing within the NICU were determined. The crucial role of health professionals in the humanization of care and its effect on the neonate-family binomial was estimated. However, conceptual changes are needed within the neonatal intensive care units. To implement humanization in daily care, family participation should be encouraged in them. For this, it is necessary to modify hospital health policies to allow changes in the infrastructure that facilitate open doors 24 h a day in special services.
Current Perspectives on Management of Type 2 Diabetes in Youth
Authors: Singhal Sachi , Kumar Seema
Published: January 2021

The prevalence of type 2 diabetes mellitus (T2DM) in children and adolescents is on the rise, and the increase in prevalence of this disorder parallels the modern epidemic of childhood obesity worldwide. T2DM affects primarily post-pubertal adolescents from ethnic/racial minorities and those from socioeconomically disadvantaged backgrounds. Youth with T2DM often have additional cardiovascular risk factors at diagnosis. T2DM in youth is more progressive in comparison to adult onset T2DM and shows lower rates of response to pharmacotherapy and more rapid development of diabetes-related complications. Lifestyle modifications and metformin are recommended as the first-line treatment for youth with T2DM in the absence of significant hyperglycemia. Assessment of pancreatic autoimmunity is recommended in all youth who appear to have T2DM. Pharmacotherapeutic options for youth with T2DM are limited at this time. Liraglutide, a GLP-1 agonist, was recently approved for T2DM in adolescents 10 years of age and older. Several clinical trials are currently underway with youth with T2DM with medications that are approved for T2DM in adults. Bariatric surgery is associated with excellent rates of remission of T2DM in adolescents with severe obesity and should be considered in selected adolescents.
Structure and Corrosion Behavior of TiO2 Thin Films Deposited by ALD on a Biomedical Magnesium Alloy
Authors: Kania Aneta , Szindler Magdalena M. , Szindler Marek
Published: January 2021

Magnesium alloys have been investigated as temporary biomaterials for orthopedic applications. Despite their high osseointegration and mechanical (bone-like) properties, Mg alloys quickly degrade in simulated physiological media. Surface coatings can be deposited onto Mg alloys to slow the corrosion rate of these biomaterials in chloride-rich environments. TiO2 films show high potential for improving the corrosion resistance of magnesium alloys. This article presents the structural observations and corrosion behavior of TiO2 thin films deposited onto a MgCa2Zn1Gd3 alloy using atomic layer deposition (ALD). Surface morphologies were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), and Raman analysis of the deposited TiO2 films was also carried out. The corrosion behavior of the uncoated alloy and the alloy coated with TiO2 was measured in Ringer’s solution at 37 °C using electrochemical and immersion tests. The microscopic observations of the TiO2 thin films with a thickness of about 52.5 and 70 nm showed that the surface morphology was homogeneous without visible defects on the TiO2 surface. The electrochemical and immersion test results showed that the thin films decreased the corrosion rate of the studied Mg-based alloy, and the corrosion resistance was higher in the thicker TiO2 film.
Effect of N-(2-Aminoethyl)-3-Aminopropyltrimethoxysilane on the Adhesion of the Modified Silicone Tie-Coating to Epoxy Primer
Authors: Zhang Hongyang , Qi Yuhong , Zhang Zhanping , Yang Qiang
Published: January 2021

In this work, modified silicone tie-paints were prepared in a simple way for securing adhesion between the epoxy anticorrosive primer and silicone fouling release coating. Hydroxy-terminated polydimethylsiloxane (PDMS) mixture containing fillers and accessory ingredient was prepared as base component. N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane (DAMO) was mechanically mixed with other functional additives as curing component. ATR-FTIR, XPS, SEM and tensile tests were used to investigate the chemical structure, morphology and mechanical properties of the tie-coatings. It was focused on the effect of the DAMO content on the adhesion of the tie-coating to epoxy primer. Peel off and shear tests were carried out to evaluate the adhesion. The results showed that introducing DAMO can significantly improve the properties of the tie-coating. The adhesion between the tie-coating and the epoxy primer increases with the increase of DAMO content, but the excessive DAMO content will decrease the fracture strength of the tie-coating and decrease the quality of the coating. When the DAMO content in tie-coating is 1.97 wt.%, the tie-coating performs excellent in the interlaminar adhesion, shear strength and mechanical properties.
Wear Resistance of Electrodeposited Ni–Mn–SiC Composite Coatings
Authors: Shi Xiaoxin , Kang Min , Fu Xiuqing , Feng Hao , Zhang Chengxin , Liu Yuntong
Published: January 2021

To improve the wear resistance of type 45 steel surfaces, Ni–Mn alloy coatings are prepared through electrodeposition under different sodium citrate concentrations based on which SiC particles of varying concentrations are added to prepare Ni–Mn–SiC composite coatings. The coatings are characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, microhardness testing, surface roughness meter, composite material surface performance testing, and laser scanning confocal microscopy. The results show that adding an appropriate concentration of sodium citrate into the electrolyte can significantly improve the Mn content in the coatings; however, an excessively high concentration increases the residual stress of the coatings and induces cracks on the surface. When the sodium citrate concentration is 40 g/L, the microhardness and wear resistance of the coatings are optimum. The average microhardness of the Ni–Mn alloy coatings is 522.8 HV0.05, and the minimum scratch area of the wear mark is 9526.26 μm2. The addition of SiC particles improves the surface integrity of the composite coatings and further improves the microhardness and wear resistance of the coatings. The composite coating has a maximum average microhardness value of 648.7 HV0.05 for SiC particle concentration of 4 g/L; this value is nearly 25% higher than that of pure Ni–Mn alloy coatings; the minimum scratch area of the wear mark is reduced to 7160.46 μm2.
Enhanced Historical Limestone Protection by New Organic/Inorganic Additive-Modified Resins
Authors: Pargoletti Eleonora , Comite Valeria , Fermo Paola , Sabatini Valentina , Cappelletti Giuseppe
Published: January 2021

The Cultural Heritage deterioration is a spontaneous decay process due to water percolation and air pollutant deposition. In this context, novel acrylic (Twinswet, TW) and siloxane-based (Alpha®SI30) resins were exploited starting from commercial products and then modified by adding either a commercial polysiloxane-based additive (TegoPhobe 1500N) or a precursor of SiO2 nanoparticles (Tetraethyl ortosilicate, TEOS) to improve the Vicenza stone surface hydrophobicity. Properties of the coated materials were studied using different techniques such as water contact angle (WCA), capillary absorption, colorimetric and water vapor permeability measurements. Accelerated UV aging and eight-month outdoor exposure tests (at Milan University campus) were also performed to determine the coatings durability. Notably, the addition of both additives slightly enhanced the surface hydrophobicity resulting in WCAs of about 140°, and decreased the water absorption especially for Alpha-based resins. Conversely, a reduction of water vapor permeability was observed, even if within the threshold value of 50%. Concerning the color variation, Alpha®SI30 preserved the stone external aspect; instead, TW smoothly modified the surface color. All of the studied coatings were stable to both UV aging and outdoor exposure. Hence, the present modified commercial coatings revealed to be very promising for the protection of historical monuments.
Collapse-Induced Multimer Formation of Self-Assembled Nanoparticles for Surface Enhanced Raman Scattering
Authors: Kim Ju Young , Oh Young Taek , Lee Su Eon , Park Jun Hyun , Park Shin , Ko Young Chun , Hwang Jun Pyo , Seon Seung Won , Yu Tae Sang , Kim Seung Hee , Lee Se Gi , Jung Min Kyu , Kim Bong Hoon
Published: January 2021

Metallic nanoparticle ensemble, with narrow inter-particle distance, is a useful element for diverse optical devices due to highly enhanced electric field intensity at the gap. Self-assembly of block copolymer (BCP) can provide the versatile solution to fabricate precise nanostructures, but this methodology has the intrinsic limitation to realize optically coupled metallic multimer geometry with narrow inter-particle distance. This is because BCP-based nanotemplate possesses a minimum size limit for interparticle distance imposed by its thermodynamic restriction. Herein, we investigate the facile formation of metallic multimer with scalability and area-selectivity through the collapse of self-assembled BCP nanopattern. The capillary-force-induced collapse phenomenon enables a spatial transformation of lateral regular ordering in metallic nanoparticle array and enhances electric field intensity. The fabrication of this metallic nanoparticle ensemble from BCP lithography is successfully utilized for surface enhanced Raman scattering (SERS). The enhancement factor of metal nanoparticle multimer is calculated as ~6.74 × 105 at 1000 cm−1, 2.04 × 106 at 1022 cm−1, and 6.11 × 106 at 1580 cm−1, respectively.
Analysis of Multi-Hit Crystals in Serial Synchrotron Crystallography Experiments Using High-Viscosity Injectors
Authors: Hadian-Jazi Marjan , Berntsen Peter , Marman Hugh , Abbey Brian , Darmanin Connie
Published: January 2021

Serial Synchrotron Crystallography (SSX) is rapidly emerging as a promising technique for collecting data for time-resolved structural studies or for performing room temperature micro-crystallography measurements using micro-focused beamlines. SSX is often performed using high frame rate detectors in combination with continuous sample scanning or high-viscosity or liquid jet injectors. When performed using ultra-bright X-ray Free Electron Laser (XFEL) sources serial crystallography typically involves a process known as ’diffract-and-destroy’ where each crystal is measured just once before it is destroyed by the intense XFEL pulse. In SSX, however, particularly when using high-viscosity injectors (HVIs) such as Lipidico, the crystal can be intercepted multiple times by the X-ray beam prior to exiting the interaction region. This has a number of important consequences for SSX including whether these multiple-hits can be incorporated into the data analysis or whether they need to be excluded due to the potential impact of radiation damage. Here, we investigate the occurrence and characteristics of multiple hits on single crystals using SSX with lipidico. SSX data are collected from crystals as they tumble within a high viscous stream of silicone grease flowing through a micro-focused X-ray beam. We confirmed that, using the Eiger 16M, we are able to collect up to 42 frames of data from the same single crystal prior to it leaving the X-ray interaction region. The frequency and occurrence of multiple hits may be controlled by varying the sample flow rate and X-ray beam size. Calculations of the absorbed dose confirm that these crystals are likely to undergo radiation damage but that nonetheless incorporating multiple hits into damage-free data should lead to a significant reduction in the number of crystals required for structural analysis when compared to just looking at a single diffraction pattern from each crystal.
LiNbO3-Tm3+ Crystal. Material for Optical Cooling
Authors: Kokanyan Ninel , Mkhitaryan Nune , Demirkhanyan Gagik , Kumar Ajith , Aillerie Michel , Sardar Dhiraj , Kokanyan Edvard
Published: January 2021

The possibilities of LiNbO3-Tm3+ crystals for optical cooling based on anti-Stokes luminescence in the wavelength range of 1818–2200 nm are investigated. The concentration dependences of the final temperature of the crystal have been determined under continuous (CW) excitation at wavelengths of 1822–1977 nm with a pump intensity Fp=5×1021 cm−2s−1. It was shown that significant cooling with ∆T = 22 K, 19 K, and 16.4 K can be achieved, respectively, with excitation at wavelengths 1977, 1967, and 1948 nm.
Solution-Based Synthesis of Sulvanite Cu3TaS4 and Cu3TaSe4 Nanocrystals
Authors: Liu Mimi , Lai Cheng-Yu , Chang Chen-Yu , Radu Daniela R.
Published: January 2021

Sulvanites have the parent formula Cu3MCh4. The metal M belongs to group 5 and Ch is a chalcogen. The tantalum sulvanites Cu3TaS4 and Cu3TaSe4 are predicted to have wide band gaps and p-type conductivity and show promise in optoelectronic applications. Their potential as p-type transparent conductors or efficient photocatalysts for visible-light water splitting is a valuable incentive to explore these materials in their nanoscale form, toward bottom-up processing opportunities. Reported herein are the first syntheses of nanosized Cu3TaS4 and Cu3TaSe4 sulvanites, which preserve the parent cubic crystal structure but show that morphology at the nanoscale is dependent of the reaction conditions. The two solution-based methods for synthesizing the tantalum S and Se sulvanites result in Cu3TaS4 or Cu3TaSe4 nanocrystals (NCs) with prismatic morphology, or, in the case of Cu3TaSe4, could lead to core-shell spherical nanostructures. The Cu3TaS4 NCs and Cu3TaSe4 NCs have good absorption in the UV-Vis region, while the Cu3TaSe4 core-shell NCs possess broad absorption bands not only in the UV-Vis but also in the near-infrared region. Photoluminescence measurements of Cu3TaS4 and Cu3TaSe4 reveal optical bandgaps of 2.54 and 2.32 eV, respectively, consistent with the values measured in bulk. Additionally, the current–voltage (I-V) curve of Cu3TaS4 NCs proves its electrical conductivity.
Early Career Stars of the Decade
Authors: Rosenblatt Charles , Gleeson Helen F.
Published: January 2021

The field of liquid crystals is constantly reinventing itself, evolving from measurements of elastic constants and devices such as the simple nematic twist cell in the 1970s to topological defects, nanoparticle inclusions, and smart sensors today [...]
Thermal Stability of Nanocrystalline Gradient Inconel 718 Alloy
Authors: Ding Jie , Zhang Yifan , Niu Tongjun , Shang Zhongxia , Xue Sichuang , Yang Bo , Li Jin , Wang Haiyan , Zhang Xinghang
Published: January 2021

Gradient structures containing nanograins in the surface layer have been introduced into Inconel 718 (IN718) nickel-based alloy using the surface mechanical grinding treatment technique. The thermal stability of the gradient IN718 alloy was investigated. Annealing studies reveal that nanograins with a grain size smaller than 40 nm exhibited significantly better thermal stability than those with larger grain size. Transmission electron microscopy analyses reveal that the enhanced thermal stability was attributed to the formation of grain boundaries with low energy configurations. This study provides new insight on strategies to improve the thermal stability of nanocrystalline metals.
Low-Cost High-Performance SnO2–Cu Electrodes for Use in Direct Ethanol Fuel Cells
Authors: Abdo Hany S. , Sarkar Amit , Gupta Madhu , Sahoo Suvadra , Mohammed Jabair A. , Ragab Sameh A. , Seikh Asiful H.
Published: January 2021

The high cost of Pt-based electrode materials limits the commercialization of fuel cells and their subsequent application in renewable energy production. It is thus necessary to develop economical, high-performance electrodes alongside biofuels to reduce the pollution associated with the production of energy. Tin dioxide–copper foil (SnO2–Cu) electrode materials are herein developed using an electrodeposition process. Cyclic voltammetry, chronoamperometry, and potentiodynamic polarization methods are used to electrochemically characterize the electrode materials, with the results revealing that their excellent catalytic properties result in them delivering a high current. The surface morphologies of the developed electrodes are examined using scanning electron microscopy, with the results showing that upon an increase in the deposition time, a finer deposit of SnO2 is formed on the surface of the Cu foil. Consequently, electrochemical oxidation using an enhanced surface area of the material leads to it exhibiting a high current and excellent corrosion resistance. Powder X-ray diffraction was used to confirm the successful depositing of SnO2 on the surface of Cu. The fuel cell fabricated using the SnO2–Cu electrode is promising for use in clean energy generation, as it can be prepared at low cost compared to conventionally used electrodes.