bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and Oligonucleotide Binding Efficiency of Differently Prepared Click Chemistry-Type DNA Microarray Slides Based on 3-Azidopropyltrimethoxysilane
Authors: Frydrych-Tomczak Emilia , Ratajczak Tomasz , Kościński Łukasz , Ranecka Agnieszka , Michalak Natalia , Luciński Tadeusz , Maciejewski Hieronim , Jurga Stefan , Lewandowski Mikołaj , Chmielewski Marcin K.
Published: May 2021

The structural characterization of glass slides surface-modified with 3-azidopropyltrimethoxysilane and used for anchoring nucleic acids, resulting in the so-called DNA microarrays, is presented. Depending on the silanization conditions, the slides were found to show different oligonucleotide binding efficiency, thus, an attempt was made to correlate this efficiency with the structural characteristics of the silane layers. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and X-ray reflectometry (XRR) measurements provided information on the surface topography, chemical composition and thickness of the silane films, respectively. The surface for which the best oligonucleotides binding efficiency is observed, has been found to consist of a densely-packed silane layer, decorated with a high-number of additional clusters that are believed to host exposed azide groups.
Analysis of Compositional Gradients in Cu(In,Ga)(S,Se)2 Solar Cell Absorbers Using Energy Dispersive X-ray Analysis with Different Acceleration Energies
Authors: Künecke Ulrike , Schuster Matthias , Wellmann Peter
Published: May 2021

The efficiency of Cu(In,Ga)(S,Se)2 (CIGSSe) solar cell absorbers can be increased by the optimization of the Ga/In and S/Se gradients throughout the absorber. Analyzing such gradients is therefore an important method in tracking the effectiveness of process variations. To measure compositional gradients in CIGSSe, energy dispersive X-ray analysis (EDX) with different acceleration energies performed at both the front surface and the backside of delaminated absorbers was used. This procedure allows for the determination of compositional gradients at locations that are millimeters apart and distributed over the entire sample. The method is therefore representative for a large area and yields information about the lateral homogeneity in the millimeter range. The procedure is helpful if methods such as secondary ion-mass (SIMS), time-of-flight SIMS, or glow-discharge optical emission spectrometry (GDOES) are not available. Results of such EDX measurements are compared with GDOES, and they show good agreement. The procedure can also be used in a targeted manner to detect local changes of the gradients in inhomogeneities or points of interest in the µm range. As an example, a comparison between the compositional gradients in the regular absorber and above the laser cut separating the Mo back contact is shown.
Effect of Sago Starch Modifications on Polystyrene/Thermoplastic Starch Blends
Authors: Ab Wahab Mohamad Kahar , Mohamad Halimatul Syahirah , Jayamani Elammaran , Ismail Hanafi , Wnuk Izabela , Przybył Anna , Stachowiak Tomasz , Postawa Przemysław
Published: May 2021

The preparation of polystyrene/thermoplastic starch (PS/TPS) blends was divided into three stages. The first stage involved the preparation of TPS from sago starch. Then, for the second stage, PS was blended with TPS to produce a TPS/PS blend. The ratios of the TPS/PS blend were 20:80, 40:60, 60:40, and 80:20. The final stage was a modification of the composition of TPS/PS blends with succinic anhydride and ascorbic acid treatment. Both untreated and treated blends were characterized by their physical, thermal, and surface morphology properties. The obtained results indicate that modified blends have better tensile strength as the adhesion between TPS and PS was improved. This can be observed from SEM micrographs, as modified blends with succinic anhydride and ascorbic acid had smaller TPS dispersion in PS/TPS blends. The micrograph showed that there was no agglomeration and void formation in the TPS/PS blending process. Furthermore, modified blends show better thermal stability, as proved by thermogravimetric analysis. Water uptake into the TPS/PS blends also decreased after the modifications, and the structural analysis showed the formation of a new peak after the modification process.
Synthesis and Characterization of Anatase TiO2 Microspheres Self-Assembled by Ultrathin Nanosheets
Authors: Di Jian , Yan Haibo , Liu Zhuoyu , Ding Xing
Published: May 2021

In this paper, we report a novel and simple method for synthesizing the microspheres self-assembled from ultrathin anatase TiO2 nanosheets with a high percentage of (001) facets via the hydrolysis process of the single-reagent (potassium fluorotitanate). We then used optical microscopy, scanning electron microscopy, and high-resolution confocal laser Raman spectroscopy to characterize the microspheres generated under different conditions. The study found that the size of the anatase TiO2 microspheres synthesized was 0.5–3 μm. As the synthesis time increased, the corroded surface of the microspheres gradually increased, resulting in the gradual disappearance of the edges and corners of the anatase nanosheets. The exposure percentage of the (001) facets of ultrathin anatase nanosheets synthesized for 2 h at 180–200 °C are close to 100%. The microsphere whose surface is completely covered by these anatase nanosheets also has nearly 100% exposed (001) facets. This new anatase nanosheet-based self-assembled microsphere will have great application potential in pollution prevention, environmental protection, and energy fields.
Isothermal Vulcanization and Non-Isothermal Degradation Kinetics of XNBR/Epoxy/XNBR-g-Halloysite Nanotubes (HNT) Nanocomposites
Authors: Paran Seyed Mohamad Reza , Naderi Ghasem , Movahedifar Elnaz , Jouyandeh Maryam , Formela Krzysztof , Colom Xavier , Cañavate Javier , Saeb Mohammad Reza
Published: May 2021

The effect of several concentrations of carboxylated nitrile butadiene rubber (XNBR) functionalized halloysite nanotubes (XHNTs) on the vulcanization and degradation kinetics of XNBR/epoxy compounds were evaluated using experimental and theoretical methods. The isothermal vulcanization kinetics were studied at various temperatures by rheometry and differential scanning calorimetry (DSC). The results obtained indicated that the nth order model could not accurately predict the curing performance. However, the autocatalytic approach can be used to estimate the vulcanization reaction mechanism of XNBR/epoxy/XHNTs nanocomposites. The kinetic parameters related to the degradation of XNBR/epoxy/XHNTs nanocomposites were also assessed using thermogravimetric analysis (TGA). TGA measurements suggested that the grafted nanotubes strongly enhanced the thermal stability of the nanocomposite.
A Stochastic FE2 Data-Driven Method for Nonlinear Multiscale Modeling
Authors: Lu Xiaoxin , Yvonnet Julien , Papadopoulos Leonidas , Kalogeris Ioannis , Papadopoulos Vissarion
Published: May 2021

A stochastic data-driven multilevel finite-element (FE2) method is introduced for random nonlinear multiscale calculations. A hybrid neural-network–interpolation (NN–I) scheme is proposed to construct a surrogate model of the macroscopic nonlinear constitutive law from representative-volume-element calculations, whose results are used as input data. Then, a FE2 method replacing the nonlinear multiscale calculations by the NN–I is developed. The NN–I scheme improved the accuracy of the neural-network surrogate model when insufficient data were available. Due to the achieved reduction in computational time, which was several orders of magnitude less than that to direct FE2, the use of such a machine-learning method is demonstrated for performing Monte Carlo simulations in nonlinear heterogeneous structures and propagating uncertainties in this context, and the identification of probabilistic models at the macroscale on some quantities of interest. Applications to nonlinear electric conduction in graphene–polymer composites are presented.
Magnetic and Transport Properties of New Dual-Phase High-Entropy Alloy FeRhIrPdPt
Authors: Baba Kohei , Ishizu Naoki , Nishizaki Terukazu , Kitagawa Jiro
Published: May 2021

High-entropy alloys (HEAs) are broadly explored from the perspective of mechanical, corrosion-resistance, catalytic, structural, superconducting, magnetic properties, and so on. In magnetic HEAs, 3d transition metals or rare-earth elements are well-studied compositional elements. We researched a magnetic HEA containing Fe combined with 4d and 5d transition metals, which has not been well investigated, and found a new dual-phase face-centered-cubic (fcc) HEA FeRhIrPdPt. The structural, magnetic, and transport properties were evaluated by assuming that FeRhIrPdPt is a mixture of FeRh4, FeIr4, FePd4, and FePt4, all with the fcc structure. The dual-phase is composed of a Rh- and Ir-rich main phase and a Pd- and Pt-rich minor one. FeRh4 and FeIr4 show spin freezings at low temperatures, while FePd4 and FePt4 are ferromagnetic. Two magnetic features can characterize FeRhIrPdPt. One is the canonical spin-glass transition at 90 K, and the other is a ferromagnetic correlation that appears below 300 K. The main and minor phases were responsible for the spin-glass transition and the ferromagnetic correlation below 300 K, respectively.
On a Riemann–Liouville Type Implicit Coupled System via Generalized Boundary Conditions
Authors: Riaz Usman , Zada Akbar , Ali Zeeshan , Popa Ioan-Lucian , Rezapour Shahram , Etemad Sina
Published: May 2021

We study a coupled system of implicit differential equations with fractional-order differential boundary conditions and the Riemann–Liouville derivative. The existence, uniqueness, and at least one solution are established by applying the Banach contraction and Leray–Schauder fixed point theorem. Furthermore, Hyers–Ulam type stabilities are discussed. An example is presented to illustrate our main result. The suggested system is the generalization of fourth-order ordinary differential equations with anti-periodic, classical, and initial boundary conditions.
Gröbner–Shirshov Bases Theory for Trialgebras
Authors: Huang Juwei , Chen Yuqun
Published: May 2021

We establish a method of Gröbner–Shirshov bases for trialgebras and show that there is a unique reduced Gröbner–Shirshov basis for every ideal of a free trialgebra. As applications, we give a method for the construction of normal forms of elements of an arbitrary trisemigroup, in particular, A.V. Zhuchok’s (2019) normal forms of the free commutative trisemigroups are rediscovered and some normal forms of the free abelian trisemigroups are first constructed. Moreover, the Gelfand–Kirillov dimension of finitely generated free commutative trialgebra and free abelian trialgebra are calculated, respectively.
Equilibrium Resolution Mechanism for Multidimensional Conflicts in Farmland Expropriation Based on a Multistage Van Damme’s Model
Authors: Tang Yang , Hong Kairong , Zou Yucheng , Zhang Yanwei
Published: May 2021

Multidimensional conflicts in farmland expropriation originate from the game of multidimensional interests between the local government and farmers. The strategy choices and equilibrium results of the two sides have evolved with changes to the situation and policy adjustments. Focusing on different types of farmland expropriation conflicts, this paper constructs a multistage Van Damme’s model of multidimensional conflicts in farmland expropriation, analyzes the stable equilibrium point of the behavior evolution of the local government and farmers under litigation settlement and nonlitigation settlement, and conducts simulation analysis on the behavior evolution and conflict resolution of both sides at different stages through MATLAB numerical simulation. The results show that (1) the interests’ game between the local government and farmers has changed periodically due to the evolution of the farmland expropriation system; (2) under litigation settlement, there is only the “government rent-seeking” conflict: in order to resolve the conflict, the cost of litigation for farmers can be reduced, while other policy interventions, such as controlling the rent-seeking ceiling of the local government and increasing the rent-seeking costs of the local government, can be implemented; (3) under nonlitigation settlement, there are three types of conflicts: to resolve the “government rent-seeking” conflict, we should control the rent-seeking ceiling of the local government and increase the rent-seeking costs of the local government or its positive social externality benefits under reasonable expropriation; to resolve the “nail household dilemma” conflict, we should increase the rent-seeking costs of farmers or their positive social externality benefits under reasonable compensation; to resolve the “extreme controversy” conflict, on the one hand, we should control the rent-seeking ceiling of farmers, and on the other hand, while controlling the rent-seeking ceiling of the local government, we should increase the farmers’ positive social externality benefits under reasonable compensation or negative social externality losses of both sides under rent seeking.
Exploring the Antecedents of Cruisers’ Destination Loyalty: Cognitive Destination Image and Cruisers’ Satisfaction
Authors: Benítez-Márquez María Dolores , Bermúdez-González Guillermo , Sánchez-Teba Eva María , Cruz-Ruiz Elena
Published: May 2021

This study is one of the few of its kind that explores the individual impact of each of the cognitive attributes of a tourist destination’s image on cruisers’ destination loyalty and overall satisfaction. It also analyzes the mediating role of satisfaction between each of the attributes and loyalty. Variance-based structural equation modeling (PLS-SEM) was used for this analysis, based on a survey of 457 cruisers visiting the city of Malaga. The results confirm that three of the five attributes, the destination’s environment image, the perceived value image of services and the accessibility image have a direct influence on cruisers’ overall satisfaction, where environment image has the most significant impact. Moreover, the results support the mediating role of satisfaction in certain cases. There is total mediation between perceived value and loyalty, as well as between accessibility image and loyalty while there is only partial complementary mediation between environment image and loyalty. The confirmation that overall satisfaction influences loyalty enables management organizations to develop more efficient loyalty strategies for their respective destinations.
Some Variants of Normal Čech Closure Spaces via Canonically Closed Sets
Authors: Gupta Ria , Das Ananga Kumar
Published: May 2021

New generalizations of normality in Čech closure space such as π-normal, weakly π-normal and κ-normal are introduced and studied using canonically closed sets. It is observed that the class of κ-normal spaces contains both the classes of weakly π-normal and almost normal Čech closure spaces.
An Improved Machine Learning-Based Employees Attrition Prediction Framework with Emphasis on Feature Selection
Authors: Najafi-Zangeneh Saeed , Shams-Gharneh Naser , Arjomandi-Nezhad Ali , Hashemkhani Zolfani Sarfaraz
Published: May 2021

Companies always seek ways to make their professional employees stay with them to reduce extra recruiting and training costs. Predicting whether a particular employee may leave or not will help the company to make preventive decisions. Unlike physical systems, human resource problems cannot be described by a scientific-analytical formula. Therefore, machine learning approaches are the best tools for this aim. This paper presents a three-stage (pre-processing, processing, post-processing) framework for attrition prediction. An IBM HR dataset is chosen as the case study. Since there are several features in the dataset, the “max-out” feature selection method is proposed for dimension reduction in the pre-processing stage. This method is implemented for the IBM HR dataset. The coefficient of each feature in the logistic regression model shows the importance of the feature in attrition prediction. The results show improvement in the F1-score performance measure due to the “max-out” feature selection method. Finally, the validity of parameters is checked by training the model for multiple bootstrap datasets. Then, the average and standard deviation of parameters are analyzed to check the confidence value of the model’s parameters and their stability. The small standard deviation of parameters indicates that the model is stable and is more likely to generalize well.
Prediction of Adsorption and Diffusion Behaviors of CO2 and CH4 in All-Silica Zeolites Using Molecular Simulation
Authors: Hasegawa Yasuhisa , Abe Chie
Published: May 2021

Computational chemistry is a promising technique for the prediction of material properties. Adsorption and diffusion behaviors in zeolite micropores are important for zeolite membranes. In this study, we investigated novel non-bonding interaction parameters of all-silica zeolites for the prediction of the adsorption and diffusion behaviors by focusing on the Si atom of zeolite frameworks. Our parameters (σ = 0.421 nm, ε = 0.954 kJ mol−1, and q = +1.10 e) were close to theoretically derived values, and the adsorption isotherms of CO2 and CH4 on several zeolites could be predicted with high accuracy. Furthermore, the parameters gave the suitable self-diffusivities of CO2 and CH4 within MFI-type zeolite micropores through molecular dynamics simulation. Those suggest that our derived parameters are useful for selecting zeolite structure as the membrane material.
Molecular Analysis of East African Lumpy Skin Disease Viruses Reveals a Mixed Isolate with Features of Both Vaccine and Field Isolates
Authors: Chibssa Tesfaye Rufael , Sombo Melaku , Lichoti Jacqueline Kasiiti , Adam Tajelser Idris Badri , Liu Yang , Elraouf Yazeed Abd , Grabherr Reingard , Settypalli Tirumala Bharani K. , Berguido Francisco J. , Loitsch Angelika , Sahle Mesfin , Cattoli Giovanni , Diallo Adama , Lamien Charles Euloge
Published: May 2021

Lumpy skin disease (LSD), an economically significant disease in cattle caused by lumpy skin disease virus (LSDV), is endemic to nearly all of Africa. Since 2012, LSDV has emerged as a significant epizootic pathogen given its rapid spread into new geographical locations outside Africa, including the Middle East, Eastern Europe, and Asia. To assess the genetic diversity of LSDVs in East Africa, we sequenced and analyzed the RPO30 and GPCR genes of LSDV in twenty-two archive samples collected in Ethiopia, Kenya, and Sudan before the appearance of LSD in the Middle East and its incursion into Europe. We compared them to publicly available sequences of LSDVs from the same region and those collected elsewhere. The results showed that the East African field isolates in this study were remarkably similar to each other and to previously sequenced field isolates of LSDV for the RPO30 and GPCR genes. The only exception was LSDV Embu/B338/2011, a field virus collected in Kenya, which displayed mixed features between the LSDV Neethling vaccine and field isolates. LSDV Embu/B338/2011 had the same 12-nucleotide insertion found in LSDV Neethling and KS-1 vaccines. Further analysis of the partial EEV glycoprotein, B22R, RNA helicase, virion core protein, NTPase, and N1R/p28-like protein genes showed that LSDV Embu/B338/2011 differs from previously described LSDV variants carrying the 12-nucleotide insertion in the GPCR gene. These findings highlight the importance of the constant monitoring of genetic variation among LSDV isolates.
Revisiting Ehrlichia ruminantium Replication Cycle Using Proteomics: The Host and the Bacterium Perspectives
Authors: Marcelino Isabel , Holzmuller Philippe , Coelho Ana , Mazzucchelli Gabriel , Fernandez Bernard , Vachiéry Nathalie
Published: May 2021

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.
Differences in Gut Microbiome Composition and Antibiotic Resistance Gene Distribution between Chinese and Pakistani University Students from a Common Peer Group
Authors: Feng Tianshu , Hilal Mian Gul , Wang Yijie , Zhou Rui , Yu Qiaoling , Qu Jiapeng , Li Huan
Published: May 2021

Gut microbiomes play important functional roles in human health and are also affected by many factors. However, few studies concentrate on gut microbiomes under exercise intervention. Additionally, antibiotic resistance genes (ARGs) carried by gut microbiomes may constantly pose a threat to human health. Here, ARGs and microbiomes of Chinese and Pakistanis participants were investigated using 16S rRNA gene sequencing and high-throughput quantitative PCR techniques. The exercise had no impact on gut microbiomes in the 12 individuals investigated during the observation period, while the different distribution of gut microbiomes was found in distinct nationalities. Overall, the dominant microbial phyla in the participants’ gut were Bacteroidota, Firmicutes and Proteobacteria. Some genera such as Prevotella and Dialister were more abundant in Pakistani participants and some other genera such as Bacteroides and Faecalibacterium were more abundant in Chinese participants. The microbial diversity in Chinese was higher than that in Pakistanis. Furthermore, microbial community structures were also different between Chinese and Pakistanis. For ARGs, the distribution of all detected ARGs is not distinct at each time point. Among these ARGs, floR was distributed differently in Chinese and Pakistani participants, and some ARGs such as tetQ and sul2 are positively correlated with several dominant microbiomes, particularly Bacteroidota and Firmicutes bacteria that did not fluctuate over time.
Variation in Human Milk Composition Is Related to Differences in Milk and Infant Fecal Microbial Communities
Authors: Pace Ryan M. , Williams Janet E. , Robertson Bianca , Lackey Kimberly A. , Meehan Courtney L. , Price William J. , Foster James A. , Sellen Daniel W. , Kamau-Mbuthia Elizabeth W. , Kamundia Egidioh W. , Mbugua Samwel , Moore Sophie E. , Prentice Andrew M. , Kita Debela G. , Kvist Linda J. , Otoo Gloria E. , Ruiz Lorena , Rodríguez Juan M. , Pareja Rossina G. , McGuire Mark A. , Bode Lars , McGuire Michelle K.
Published: May 2021

Previously published data from our group and others demonstrate that human milk oligosaccharide (HMOs), as well as milk and infant fecal microbial profiles, vary by geography. However, little is known about the geographical variation of other milk-borne factors, such as lactose and protein, as well as the associations among these factors and microbial community structures in milk and infant feces. Here, we characterized and contrasted concentrations of milk-borne lactose, protein, and HMOs, and examined their associations with milk and infant fecal microbiomes in samples collected in 11 geographically diverse sites. Although geographical site was strongly associated with milk and infant fecal microbiomes, both sample types assorted into a smaller number of community state types based on shared microbial profiles. Similar to HMOs, concentrations of lactose and protein also varied by geography. Concentrations of HMOs, lactose, and protein were associated with differences in the microbial community structures of milk and infant feces and in the abundance of specific taxa. Taken together, these data suggest that the composition of human milk, even when produced by relatively healthy women, differs based on geographical boundaries and that concentrations of HMOs, lactose, and protein in milk are related to variation in milk and infant fecal microbial communities.
Comparison of Resveratrol Supplementation and Energy Restriction Effects on Sympathetic Nervous System Activity and Vascular Reactivity: A Randomized Clinical Trial
Authors: Gonçalinho Gustavo Henrique Ferreira , Roggerio Alessandra , Goes Marisa Fernandes da Silva , Avakian Solange Desirée , Leal Dalila Pinheiro , Strunz Célia Maria Cassaro , Mansur Antonio de Padua
Published: May 2021

Background: Chronic sympathetic nervous system activation is associated with endothelial dysfunction and cardiometabolic disease, which may be modulated by resveratrol (RSV) and energy restriction (ER). This study aimed to examine the effects of RSV and ER on plasma noradrenaline (NA), flow-mediated vasodilation (ed-FMD), and endothelium-independent nitrate-mediated vasodilation (ei-NMD). Methods: The study included 48 healthy adults randomized to 30-days intervention of RSV or ER. Results: Waist circumference, total cholesterol, HDL-c, LDL-c, apoA-I, and plasma NA decreased in the ER group, whilst RSV increased apoB and total cholesterol, without changing plasma NA. No effects on vascular reactivity were observed in both groups. Plasma NA change was positively correlated with total cholesterol (r = 0.443; p = 0.002), triglycerides (r = 0.438; p = 0.002), apoA-I (r = 0.467; p = 0.001), apoB (r = 0.318; p = 0.032) changes, and ei-NMD (OR = 1.294; 95%CI: 1.021–1.640). Conclusions: RSV does not improve cardiometabolic risk factors, sympathetic activity, and endothelial function. ER decreases plasma NA and waist circumference as well as improves blood lipids, but does not modify endothelial function. Finally, plasma NA was associated with ei-NMD, which could be attributed to a higher response to nitrate in patients with greater resting sympathetic vasoconstriction.
Predicting Deliquescence Relative Humidities of Crystals and Crystal Mixtures
Authors: Veith Heiner , Luebbert Christian , Sadowski Gabriele
Published: May 2021

The presence of water in the form of relative humidity (RH) may lead to deliquescence of crystalline components above a certain RH, the deliquescence RH (DRH). Knowing the DRH values is essential, e.g., for the agrochemical industry, food industry, and pharmaceutical industry to identify stability windows for their crystalline products. This work applies the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) to purely predict the DRH of single components (organic acids, sugars, artificial sweeteners, and amides) and multicomponent crystal mixtures thereof only based on aqueous solubility data of the pure components. The predicted DRH values very well agree with the experimental ones. In addition, the temperature influence on the DRH value could be successfully predicted with PC-SAFT. The DRH prediction also differentiates between formation of hydrates and anhydrates. PC-SAFT-predicted phase diagrams of hydrate-forming components illustrate the influence of additional components on the hydrate formation as a function of RH. The DRH prediction via PC-SAFT allows for the determining of the stability of crystals and crystal mixtures without the need for time-consuming experiments.
Integration of Mesoporous Bioactive Glass Nanoparticles and Curcumin into PHBV Microspheres as Biocompatible Composite for Drug Delivery Applications
Authors: Aguilar-Rabiela Arturo E. , Leal-Egaña Aldo , Nawaz Qaisar , Boccaccini Aldo R.
Published: May 2021

Bioactive glasses (BGs) are being increasingly considered for biomedical applications. One convenient approach to utilize BGs in tissue engineering and drug delivery involves their combination with organic biomaterials in order to form composites with enhanced biocompatibility and biodegradability. In this work, mesoporous bioactive glass nanoparticles (MBGN) have been merged with polyhydroxyalkanoate microspheres with the purpose to develop drug carriers. The composite carriers (microspheres) were loaded with curcumin as a model drug. The toxicity and delivery rate of composite microspheres were tested in vitro, reaching a curcumin loading efficiency of over 90% and an improving of biocompatibility of different concentrations of MBGN due to its administrations through the composite. The composite microspheres were tested in terms of controlled release, biocompatibility and bioactivity. Our results demonstrate that the composite microspheres can be potentially used in biomedicine due to their dual effects: bioactivity (due to the presence of MBGN) and curcumin release capability.
Evaluation of Substituted N-Phenylpiperazine Analogs as D3 vs. D2 Dopamine Receptor Subtype Selective Ligands
Authors: Lee Boeun , Taylor Michelle , Griffin Suzy A. , McInnis Tamara , Sumien Nathalie , Mach Robert H. , Luedtke Robert R.
Published: May 2021

N-phenylpiperazine analogs can bind selectively to the D3 versus the D2 dopamine receptor subtype despite the fact that these two D2-like dopamine receptor subtypes exhibit substantial amino acid sequence homology. The binding for a number of these receptor subtype selective compounds was found to be consistent with their ability to bind at the D3 dopamine receptor subtype in a bitopic manner. In this study, a series of the 3-thiophenephenyl and 4-thiazolylphenyl fluoride substituted N-phenylpiperazine analogs were evaluated. Compound 6a was found to bind at the human D3 receptor with nanomolar affinity with substantial D3 vs. D2 binding selectivity (approximately 500-fold). Compound 6a was also tested for activity in two in-vivo assays: (1) a hallucinogenic-dependent head twitch response inhibition assay using DBA/2J mice and (2) an L-dopa-dependent abnormal involuntary movement (AIM) inhibition assay using unilateral 6-hydroxydopamine lesioned (hemiparkinsonian) rats. Compound 6a was found to be active in both assays. This compound could lead to a better understanding of how a bitopic D3 dopamine receptor selective ligand might lead to the development of pharmacotherapeutics for the treatment of levodopa-induced dyskinesia (LID) in patients with Parkinson’s disease.
Advanced Materials Based on Nanosized Hydroxyapatite
Authors: Rial Ramón , González-Durruthy Michael , Liu Zhen , Ruso Juan M.
Published: May 2021

The development of new materials based on hydroxyapatite has undergone a great evolution in recent decades due to technological advances and development of computational techniques. The focus of this review is the various attempts to improve new hydroxyapatite-based materials. First, we comment on the most used processing routes, highlighting their advantages and disadvantages. We will now focus on other routes, less common due to their specificity and/or recent development. We also include a block dedicated to the impact of computational techniques in the development of these new systems, including: QSAR, DFT, Finite Elements of Machine Learning. In the following part we focus on the most innovative applications of these materials, ranging from medicine to new disciplines such as catalysis, environment, filtration, or energy. The review concludes with an outlook for possible new research directions.
Crosslinked Silk Fibroin/Gelatin/Hyaluronan Blends as Scaffolds for Cell-Based Tissue Engineering
Authors: Duangpakdee Anongnart , Laomeephol Chavee , Jindatip Depicha , Thongnuek Peerapat , Ratanavaraporn Juthamas , Damrongsakkul Siriporn
Published: May 2021

3D porous scaffolds fabricated from binary and ternary blends of silk fibroin (SF), gelatin (G), and hyaluronan (HA) and crosslinked by the carbodiimide coupling reaction were developed. Water-stable scaffolds can be obtained after crosslinking, and the SFG and SFGHA samples were stable in cell culture medium up to 10 days. The presence of HA in the scaffolds with appropriate crosslinking conditions greatly enhanced the swellability. The microarchitecture of the freeze-dried scaffolds showed high porosity and interconnectivity. In particular, the pore size was significantly larger with an addition of HA. Biological activities of NIH/3T3 fibroblasts seeded on SFG and SFGHA scaffolds revealed that both scaffolds were able to support cell adhesion and proliferation of a 7-day culture. Furthermore, cell penetration into the scaffolds can be observed due to the interconnected porous structure of the scaffolds and the presence of bioactive materials which could attract the cells and support cell functions. The higher cell number was noticed in the SFGHA samples, possibly due to the HA component and the larger pore size which could improve the microenvironment for fibroblast adhesion, proliferation, and motility. The developed scaffolds from ternary blends showed potential in their application as 3D cell culture substrates in fibroblast-based tissue engineering.
Heart Failure and PAHs, OHPAHs, and Trace Elements Levels in Human Serum: Results from a Preliminary Pilot Study in Greek Population and the Possible Impact of Air Pollution
Authors: Chrysochou Eirini , Kanellopoulos Panagiotis Georgios , Koukoulakis Konstantinos G. , Sakellari Aikaterini , Karavoltsos Sotirios , Minaidis Minas , Bakeas Evangelos
Published: May 2021

Cardiovascular diseases (CVDs) have been associated with environmental pollutants. The scope of this study is to assess any potential relation of polycyclic aromatic hydrocarbons (PAHs), their hydroxylated derivatives, and trace elements with heart failure via their direct determination in human serum of Greek citizens residing in different areas. Therefore, we analyzed 131 samples including cases (heart failure patients) and controls (healthy donors), and the respective demographic data were collected. Significantly higher concentrations (p < 0.05) were observed in cases’ serum regarding most of the examined PAHs and their derivatives with phenanthrene, fluorene, and fluoranthene being the most abundant (median of >50 μg L−1). Among the examined trace elements, As, Cd, Cu, Hg, Ni, and Pb were measured at statistically higher concentrations (p < 0.05) in cases’ samples, with only Cr being significantly higher in controls. The potential impact of environmental factors such as smoking and area of residence has been evaluated. Specific PAHs and trace elements could be possibly related with heart failure development. Atmospheric degradation and smoking habit appeared to have a significant impact on the analytes’ serum concentrations. PCA–logistic regression analysis could possibly reveal common mechanisms among the analytes enhancing the hypothesis that they may pose a significant risk for CVD development.
Bertholletia excelsa Seeds Reduce Anxiety-Like Behavior, Lipids, and Overweight in Mice
Authors: Frausto-González Oswaldo , Bautista Claudia J. , Narváez-González Fernando , Hernandez-Leon Alberto , Estrada-Camarena Erika , Rivero-Cruz Fausto , González-Trujano María Eva
Published: May 2021

Overweight, obesity, and psychiatric disorders are serious health problems. To evidence the anxiolytic-like effects and lipid reduction in mice receiving a high-calorie diet and Bertholletia excelsa seeds in a nonpolar extract (SBHX, 30 and 300 mg/kg), animals were assessed in open-field, hole-board, and elevated plus-maze tests. SBHX (3 and 10 mg/kg) potentiated the pentobarbital-induced hypnosis. Chronic administration of SBHX for 40 days was given to mice fed with a hypercaloric diet to determine the relationship between water and food intake vs. changes in body weight. Testes, epididymal white adipose tissue (eWAT), and liver were dissected to analyze fat content, triglycerides, cholesterol, and histological effects after administering the hypercaloric diet and SBHX. Fatty acids, such as palmitoleic acid (0.14%), palmitic acid (21.42%), linoleic acid (11.02%), oleic acid (59.97%), and stearic acid (7.44%), were identified as constituents of SBHX, producing significant anxiolytic-like effects and preventing body-weight gain in mice receiving the hypercaloric diet without altering their water or food consumption. There was also a lipid-lowering effect on the testicular tissue and eWAT and a reduction of adipocyte area in eWAT. Our data evidence beneficial properties of B. excelsa seeds influencing global health concerns such as obesity and anxiety.
Comparison of Nonheme Manganese- and Iron-Containing Flavone Synthase Mimics
Authors: Lakk-Bogáth Dóra , Juraj Natalija Pantalon , Meena Bashdar I. , Perić Berislav , Kirin Srećko I. , Kaizer József
Published: May 2021

Heme and nonheme-type flavone synthase enzymes, FS I and FS II are responsible for the synthesis of flavones, which play an important role in various biological processes, and have a wide range of biomedicinal properties including antitumor, antimalarial, and antioxidant activities. To get more insight into the mechanism of this curious enzyme reaction, nonheme structural and functional models were carried out by the use of mononuclear iron, [FeII(CDA-BPA*)]2+ (6) [CDA-BPA = N,N,N’,N’-tetrakis-(2-pyridylmethyl)-cyclohexanediamine], [FeII(CDA-BQA*)]2+ (5) [CDA-BQA = N,N,N’,N’-tetrakis-(2-quinolilmethyl)-cyclohexanediamine], [FeII(Bn-TPEN)(CH3CN)]2+ (3) [Bn-TPEN = N-benzyl-N,N’,N’-tris(2-pyridylmethyl)-1,2-diaminoethane], [FeIV(O)(Bn-TPEN)]2+ (9), and manganese, [MnII(N4Py*)(CH3CN)]2+ (2) [N4Py* = N,N-bis(2-pyridylmethyl)-1,2-di(2-pyridyl)ethylamine)], [MnII(Bn-TPEN)(CH3CN)]2+ (4) complexes as catalysts, where the possible reactive intermediates, high-valent FeIV(O) and MnIV(O) are known and well characterised. The results of the catalytic and stoichiometric reactions showed that the ligand framework and the nature of the metal cofactor significantly influenced the reactivity of the catalyst and its intermediate. Comparing the reactions of [FeIV(O)(Bn-TPEN)]2+ (9) and [MnIV(O)(Bn-TPEN)]2+ (10) towards flavanone under the same conditions, a 3.5-fold difference in reaction rate was observed in favor of iron, and this value is three orders of magnitude higher than was observed for the previously published [FeIV(O)(N2Py2Q*)]2+ [N,N-bis(2-quinolylmethyl)-1,2-di(2-pyridyl)ethylamine] species.
Advanced Oxidation Processes and Biotechnological Alternatives for the Treatment of Tannery Wastewater
Authors: Urbina-Suarez Néstor Andrés , Machuca-Martínez Fiderman , Barajas-Solano Andrés F.
Published: May 2021

The tannery industry is one of the economic sectors that contributes to the development of different countries. Globally, Europe and Asia are the main producers of this industry, although Latin America and Africa have been growing considerably in recent years. With this growth, the negative environmental impacts towards different ecosystem resources as a result of the discharges of recalcitrated pollutants, have led to different investigations to generate alternative solutions. Worldwide, different technologies have been studied to address this problem, biological and physicochemical processes have been widely studied, presenting drawbacks with some recalcitrant compounds. This review provides a context on the different existing technologies for the treatment of tannery wastewater, analyzing the physicochemical composition of this liquid waste, the impact it generates on human health and ecosystems and the advances in the different existing technologies, focusing on advanced oxidation processes and the use of microalgae. The coupling of advanced oxidation processes with biological processes, mainly microalgae, is seen as a viable biotechnological strategy, not only for the removal of pollutants, but also to obtain value-added products with potential use in the biorefining of the biomass.
The Primary Origin of Excellent Dielectric Properties of (Co, Nb) Co-Doped TiO2 Ceramics: Electron-Pinned Defect Dipoles vs. Internal Barrier Layer Capacitor Effect
Authors: Nachaithong Theeranuch , Chanlek Narong , Moontragoon Pairot , Thongbai Prasit
Published: May 2021

(Co, Nb) co-doped rutile TiO2 (CoNTO) nanoparticles with low dopant concentrations were prepared using a wet chemistry method. A pure rutile TiO2 phase with a dense microstructure and homogeneous dispersion of the dopants was obtained. By co-doping rutile TiO2 with 0.5 at.% (Co, Nb), a very high dielectric permittivity of ε′ ≈ 36,105 and a low loss tangent of tanδ ≈ 0.04 were achieved. The sample–electrode contact and resistive outer-surface layer (surface barrier layer capacitor) have a significant impact on the dielectric response in the CoNTO ceramics. The density functional theory calculation shows that the 2Co atoms are located near the oxygen vacancy, creating a triangle-shaped 2CoVoTi complex defect. On the other hand, the substitution of TiO2 with Nb atoms can form a diamond-shaped 2Nb2Ti complex defect. These two types of complex defects are far away from each other. Therefore, the electron-pinned defect dipoles cannot be considered the primary origins of the dielectric response in the CoNTO ceramics. Impedance spectroscopy shows that the CoNTO ceramics are electrically heterogeneous, comprised of insulating and semiconducting regions. Thus, the dielectric properties of the CoNTO ceramics are attributed to the interfacial polarization at the internal insulating layers with very high resistivity, giving rise to a low loss tangent.
Long-Term Effect of a Gluten-Free Diet on Diarrhoea- or Bloating-Predominant Functional Bowel Disease: Role of the ‘Low-Grade Coeliac Score’ and the ‘Coeliac Lymphogram’ in the Response Rate to the Diet
Authors: Fernández-Bañares Fernando , Arau Beatriz , Raga Agnès , Aceituno Montserrat , Tristán Eva , Carrasco Anna , Ruiz Laura , Martín-Cardona Albert , Ruiz-Ramírez Pablo , Esteve Maria
Published: May 2021

1. Background: The long-term effect of a gluten-free diet (GFD) on functional bowel disorders (FBDs) has been scarcely studied. The aim was to assess the effect of a GFD on FBD patients, and to assess the role of both the low-grade coeliac score and coeliac lymphogram in the probability of response to a GFD. 2. Methods: 116 adult patients with either predominant diarrhoea or abdominal bloating, fulfilling Rome IV criteria of FBD, were treated with a GFD. Duodenum biopsies were performed for both pathology studies and intraepithelial lymphocyte subpopulation patterns. Coeliac lymphogram was defined as an increase in TCRγδ+ cells plus a decrease in CD3− cells. A low-grade coeliac score >10 was considered positive. 3. Results: Sustained response to GFD was observed in 72 patients (62%) after a median of 21 months of follow-up, who presented more often with coeliac lymphogram (37.5 vs. 11.4%; p = 0.02) and a score >10 (32 vs. 11.4%; p = 0.027) compared to non-responders. The frequency of low-grade coeliac enteropathy was 19.8%. 4. Conclusion: A GFD is effective in the long-term treatment of patients with previously unexplained chronic watery diarrhoea- or bloating-predominant symptoms fulfilling the criteria of FBD. The response rate was much higher in the subgroup of patients defined by the presence of both a positive low-grade coeliac score and coeliac lymphogram.
Nutritional Iodine Status in Pregnant Women from Health Area IV in Asturias (Spain): Iodised Salt Is Enough
Authors: González-Martínez Silvia , Riestra-Fernández María , Martínez-Morillo Eduardo , Avello-Llano Noelia , Delgado-Álvarez Elías , Menéndez-Torre Edelmiro Luis
Published: May 2021

Background: Iodine deficiency during pregnancy may have adverse effects on the neurodevelopment of the foetus. Recent studies of pregnant women in Asturias (Spain) indicate that nutritional iodine levels are sufficient. The objective of this study was to confirm the appropriate nutritional iodine status and to analyse the influence of the ingestion of iodine on maternal urinary iodine concentration (UIC) and thyroid function. Methods: An observational study was carried out between May and June 2017 on women in the first trimester of pregnancy from Health Area IV in Asturias. The women completed a questionnaire related to their consumption of iodine and samples were taken to analyse UIC and thyroid function. Results: Three hundred and eighteen pregnant women were involved. Of these, 51.10% used iodised salt, 48.90% consumed ≥ 2 servings of dairy products daily and 87.08% took iodine supplements. The median UIC was 171.5 μg/L (116–265 μg/L) and 60.41% of women had UIC ≥ 150 μg/L. Multivariate logistic regression analysis demonstrated that iodised salt had a protective effect on UIC < 150 μg/L (odds ratio (OR) 0.404 (0.237–0.683), p = 0.001), but not iodine supplements (OR 0.512 (0.240–1.085), p = 0.080). The average level of thyroid stimulating hormone (TSH) was 2.26 ± 0.94 mIU/L; 68.40% of pregnant women taking iodine supplements had TSH < 2.5 mIU/L compared to 30.00% of those who were not taking supplements (p = 0.031). Conclusions: The pregnant women in our health area are maintaining appropriate nutritional iodine levels. The consumption of iodised salt protects against iodine deficiency; thus, iodine supplements should be taken on an individualised basis.
Pandemic Effects and Gluten-Free Diet: An Adherence and Mental Health Problem
Authors: Bascuñán Karla A. , Rodríguez Juan Manuel , Osben Carla , Fernández Alan , Sepúlveda Carlos , Araya Magdalena
Published: May 2021

The COVID-19 pandemic has been present for many months, influencing diets such as the gluten-free diet (GFD), which implies daily challenges even in non-pandemic conditions. Persons following the GFD were invited to answer online ad hoc and validated questionnaires characterizing self-perceptions of the pandemic, current clinical condition, dietary characteristics, adherence to GFD, anxiety, and depression. Of 331 participants, 87% experienced shortage and higher cost of food and 14.8% lost their jobs. Symptoms increased in 29% and 36.6% failed to obtain medical help. Although 52.3% increased food preparation at home and purchased alternative foodstuffs, 53.8% had consumed gluten-containing foods. The Health Eating Index was intermediate/“needs improvement” (mean 65.6 ± 13.3 points); in 49.9% (perception) and 44.4% (questionnaire), adherence was “bad”. Anxiety and depression scores were above the cutoff in 28% and 40.4%, respectively. Adherence and mental health were strongly related. The likelihood of poor adherence was 2.3 times higher (p < 0.004) in participants declaring that pandemic altered GFD. Those suffering depressive symptoms were 1.3 times more likely to have poor adherence (p < 0.000). Depression and faulty GFD (mandatory for treatment) appear, affecting a high proportion of participants, suggesting that support measures aimed at these aspects would help improve the health condition of people that maintain GFD. Comparisons of data currently appearing in the literature available should be cautious because not only cultural aspects but conditions and timing of data collection are most variable.