bluuebunny/crossref_metadata_2025 huggingface dataset:
POM/EVA Blends with Future Utility in Fused Deposition Modeling
Authors: Galeja Mateusz , Wypiór Klaudiusz , Wachowicz Jan , Kędzierski Przemysław , Hejna Aleksander , Marć Mariusz , Klewicz Krzysztof , Gabor Jadwiga , Okła Hubert , Swinarew Andrzej Szymon
Published: June 2020

Polyoxymethylene (POM) is one of the most popular thermoplastic polymers used in the industry. Therefore, the interest in its potential applications in rapid prototyping is understandable. Nevertheless, its low dimensional stability causes the warping of 3D prints, limiting its applications. This research aimed to evaluate the effects of POM modification with ethylene-vinyl acetate (EVA) (2.5, 5.0, and 7.5 wt.%) on its processing (by melt flow index), structure (by X-ray microcomputed tomography), and properties (by static tensile tests, surface resistance, contact angle measurements, differential scanning calorimetry, and thermogravimetric analysis), as well as very rarely analyzed emissions of volatile organic compounds (VOCs) (by headspace analysis). Performed modifications decreased stiffness and strength of the material, simultaneously enhancing its ductility, which simultaneously increased the toughness even by more than 50% for 7.5 wt.% EVA loading. Such an effect was related to an improved linear flow rate resulting in a lack of defects inside the samples. The decrease of the melting temperature and the slight increase of thermal stability after the addition of EVA broadened the processing window for 3D printing. The 3D printing trials on two different printers showed that the addition of EVA copolymer increased the possibility of a successful print without defects, giving space for further development.
Sulfonic Acid Derivative-Modified SBA-15, PHTS and MCM-41 Mesoporous Silicas as Carriers for a New Antiplatelet Drug: Ticagrelor Adsorption and Release Studies
Authors: Moritz Michał , Geszke-Moritz Małgorzata
Published: June 2020

Three mesoporous, siliceous materials, i.e., SBA-15 (Santa Barbara Amorphous), PHTS (Plugged Hexagonal Templated Silica) and MCM-41 (Mobil Composition of Matter), functionalized with a sulfonic acid derivative, were successfully prepared and applied as the carriers for the poorly water-soluble drug, ticagrelor. The siliceous carriers were characterized using nitrogen sorption analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and elemental analysis. The adsorption studies were conducted in acetonitrile. At the highest equilibrium concentrations, the amount of ticagrelor Qe that adsorbed onto the examined silicas was in the range of 83 to 220 mg/g, increasing in the following order: PHTS-(CH2)3-SO3H < SBA-15-(CH2)3-SO3H < MCM-41-(CH2)3-SO3H. The equilibrium adsorption data were analyzed using the Freundlich, Jovanovich, Langmuir, Temkin, Dubinin-Radushkevich, Dubinin-Astakhov and Redlich-Peterson models. In order to find the best-fit isotherm for each model, a nonlinear fitting analysis was carried out. Based on the minimized values of the ARE function, the fit of the isotherms to the experimental points for ticagrelor adsorption onto the modified silicas can be ordered as follows: SBA-15-(CH2)3-SO3H (Redlich-Peterson > Dubinin-Astakhov > Temkin), PHTS-(CH2)3-SO3H (Redlich-Peterson > Temkin > Dubinin-Astakhov), MCM-41-(CH2)3-SO3H (Redlich-Peterson > Dubinin-Astakhov > Langmuir). The values of adsorption energy (above 8 kJ/mol) indicate the chemical nature of ticagrelor adsorption onto propyl-sulfonic acid-modified silicas. The results of release studies indicated that at pH 4.5, modified SBA-15 and MCM-41 carriers accelerate the drug dissolution process, compared to the dissolution rate of free crystalline ticagrelor. Intriguingly, modified PHTS silica provides prolonged drug release kinetics compared to other siliceous adsorbents and to the dissolution rate of crystalline ticagrelor. A Weibull release model was employed to describe the release profiles of ticagrelor from the prepared carriers. The time necessary to dissolve 50% and 90% of ticagrelor from mesoporous adsorbents at pH 4.5 increased in the following order: SBA-15-(CH2)3-SO3H < MCM-41-(CH2)3-SO3H < PHTS-(CH2)3-SO3H.
Numeric Analysis on Shear Behavior of High-Strength Concrete Single-Keyed Dry Joints with Fixing Imperfections in Precast Concrete Segmental Bridges
Authors: Jiang Haibo , Chen Mingzhu , Sha Zhijun , Xiao Jie , Feng Jiahui
Published: June 2020

Fixing imperfections in keyed dry joints between the concrete segments compromise the performance of precast concrete segmental bridges (PCSBs), which needs to consider carefully. In this study, a finite-element model on high-strength concrete single-keyed dry joints in PCSBs was established and validated by experimental results. Parametric studies on fixing imperfections in key, concrete strengths, and confining pressures were carried out based on that model. The numeric results included crack patterns, load–displacements and shear strength. Fixing imperfections—especially at lower surface of keys—reduced shear strength of single-keyed dry joints by the different shear transfer mechanism. Higher confining pressure and concrete strength improved the shear strength, but they mitigated and aggravated the effect of fixing imperfections at lower surface of key on shear strength, respectively. Compared with simulating results, AASHTO standard overestimated the shear capacity of single-keyed dry joints with fixing imperfections at lower surface of key by up to 0.602–22.0%, but greatly underestimated that of the rest. A modified formula with a strength reduction factor was proposed. For six experimental three-keyed dry-joint specimens and 30 numeric single-keyed dry-joint specimens with or without fixing imperfections, the average ratio of code predictions to experimental results was 90.4% and 81.6%, respectively.
Feasibility of Reduced Ingot Hot-Top Height for the Cost-Effective Forging of Heavy Steel Ingots
Authors: Kim Nam Yong , Ko Dae-Cheol , Kim Yangjin , Han Sang Wook , Oh Il Yeong , Moon Young Hoon
Published: June 2020

Feasibility studies have been performed on ingots with reduced hot-top heights for the cost-effective hot forging of heavy ingots. The quality of the heavy ingots is generally affected by internal voids, which have been known to be accompanied by inclusions and segregation. To guarantee the expected mechanical performance of the forged products, these voids should be closed and eliminated during the hot open die forging process. Hence, to effectively control the internal voids, the optimum hot-top height and forging schedules need to be determined. In order to improve the utilization ratio of ingots, the ingot hot-top height needs to be minimized. To investigate the effect of the reduced hot-top height on the forged products, shaft and bar products have been manufactured via hot forging of ingots having various hot-top heights. From the operational results, the present work suggests effective forging processes to produce acceptable shaft and bar products using ingots having reduced hot tops. The mechanical properties of shop-floor products manufactured from ingots with reduced hot tops have also been measured and compared with those of conventional ingot products.
Wear Simulation of Ceramic-on-Crosslinked Polyethylene Hip Prostheses: A New Non-Oxide Silicon Nitride versus the Gold Standard Composite Oxide Ceramic Femoral Heads
Authors: Yorifuji Makiko , Affatato Saverio , Tateiwa Toshiyuki , Takahashi Yasuhito , Shishido Takaaki , Marin Elia , Zanocco Matteo , Zhu Wenliang , Pezzotti Giuseppe , Yamamoto Kengo
Published: June 2020

The purpose of the present study was to compare the wear behavior of ceramic-on-vitamin-E-diffused crosslinked polyethylene (Vit-E XLPE) hip bearings employing the gold standard oxide ceramic, zirconia (ZrO2)-toughened alumina (Al2O3) (ZTA, BIOLOX®delta) and a new non-oxide ceramic, silicon nitride (Si3N4, MC2®). In vitro wear test was performed using a 12-station hip joint simulator. The test was carried out by applying the kinematic inputs and outputs as recommended by ISO 14242-1:2012. Vitamin-E-diffused crosslinked polyethylene (Vit-E XLPE) acetabular liners (E1®) were coupled with Ø28-mm ZTA and Si3N4 femoral heads. XLPE liner weight loss over 5 million cycles (Mc) of testing was compared between the two different bearing couples. Surface topography, phase contents, and residual stresses were analyzed by contact profilometer and Raman microspectroscopy. Vit-E XLPE liners coupled with Si3N4 heads produced slightly lower wear rates than identical liners with ZTA heads. The mean wear rates (corrected for fluid absorption) of liners coupled with ZTA and Si3N4 heads were 0.53 ± 0.24 and 0.49 ± 0.23 mg/Mc after 5 Mc of simulated gait, respectively. However, after wear testing, the ZTA heads retained a smoother topography and showed fewer surface stresses than the Si3N4 ones. Note that no statistically significant differences were found in the above comparisons. This study suggests that the tribochemically formed soft silica layer on the Si3N4 heads may have reduced friction and slightly lowered the wear of the Vit-E XLPE liners. Considering also that the toughness of Si3N4 is superior to ZTA, the present wear data represent positive news in the future development of long-lasting hip components.
Water Retention Mechanism of HPMC in Cement Mortar
Authors: Chen Ning , Wang Peiming , Zhao Liqun , Zhang Guofang
Published: June 2020

In this paper, the effect of HPMC (hydroxypropyl methyl cellulose ether) on the cement mortar water retention (WR) and composition was studied. The relationship between the plastic viscosity and water retention of cement mortar was revealed. The results showed that HPMC formed a colloidal film with a 3D network structure in water, which changed the ability of water to migrate. The HPMC colloid adsorbed on the surface of cement and sand particles and played a bridging role due to the influence of the spatial network structure of the thin film. Fine particles formed a grid-like distribution, and the hydration products formed a unique fibrous tree-like structure. A positive correlation was observed between the plastic viscosity and the water holding capacity of cement mortar. Finally, the mechanism responsible for the improved water retention of cement mortar by HPMC was analyzed using the changing water migration capacity, migration channels, and mortar cohesion.
Simulation of Natural Convection in a Concentric Hexagonal Annulus Using the Lattice Boltzmann Method Combined with the Smoothed Profile Method
Authors: Alapati Suresh
Published: June 2020

This research work presents results obtained from the simulation of natural convection inside a concentric hexagonal annulus by using the lattice Boltzmann method (LBM). The fluid flow (pressure and velocity fields) inside the annulus is evaluated by LBM and a finite difference method (FDM) is used to get the temperature filed. The isothermal and no-slip boundary conditions (BC) on the hexagonal edges are treated with a smooth profile method (SPM). At first, for validating the present simulation technique, a standard benchmarking problem of natural convection inside a cold square cavity with a hot circular cylinder is simulated. Later, natural convection simulations inside the hexagonal annulus are carried out for different values of the aspect ratio, AR (ratio of the inner and outer hexagon sizes), and the Rayleigh number, Ra. The simulation results are presented in terms of isotherms (temperature contours), streamlines, temperature, and velocity distributions inside the annulus. The results show that the fluid flow intensity and the size and number of vortex pairs formed inside the annulus strongly depend on AR and Ra values. Based on the concentric isotherms and weak fluid flow intensity at the low Ra, it is observed that the heat transfer inside the annulus is dominated by the conduction mode. However, multiple circulation zones and distorted isotherms are observed at the high Ra due to the strong convective flow. To further access the accuracy and robustness of the present scheme, the present simulation results are compared with the results given by the commercial software, ANSYS-Fluent®. For all combinations of AR and Ra values, the simulation results of streamlines and isotherms patterns, and temperature and velocity distributions inside the annulus are in very good agreement with those of the Fluent software.
Lung Ultrasound and Clinical Progression of Acute Bronchiolitis: A Prospective Observational Single-Center Study
Authors: Di Mauro Antonio , Cappiello Anna Rita , Ammirabile Angela , Abbondanza Nicla , Bianchi Francesco Paolo , Tafuri Silvio , Manzionna Mariano M.
Published: June 2020

Background and Objectives: Recent literature suggests that lung ultrasound might have a role in the diagnosis and management of bronchiolitis. The aim of the study is to evaluate the relationship between an ultrasound score and the clinical progression of bronchiolitis: need for supplemental oxygen, duration of oxygen therapy and hospital stay. Materials and Methods: This was a prospective observational single-center study, conducted in a pediatric unit during the 2017–2018 epidemic periods. All consecutive patients admitted with clinical signs of acute bronchiolitis, but without the need for supplemental oxygen, underwent a lung ultrasound in the first 24 h of hospital care. The lung involvement was graded based on the ultrasound score. During clinical progression, need for supplemental oxygen, duration of oxygen therapy and duration of hospital stay were recorded. Results: The final analysis included 83 patients, with a mean age of 4.5 ± 4.1 months. The lung ultrasound score in patients that required supplemental oxygen during hospitalization was 4.5 ± 1.7 (range: 2.0–8.0), different from the one of the not supplemented infants (2.5 ± 1.8; range: 0.0–6.0; p < 0.001). Ultrasound score was associated with the need for supplemental oxygen (OR = 2.2; 95% CI = 1.5–3.3; p < 0.0001). Duration of oxygen therapy was not associated with LUS score (p > 0.05). Length of hospital stay (coef. = 0.5; 95% CI = 0.2–0.7; p < 0.0001) correlates with LUS score. Conclusion: Lung ultrasound score correlates with the need of supplemental oxygen and length of hospital stay in infants with acute bronchiolitis.
Close Correlation between Frailty and Depressive State in Chronic Liver Diseases
Authors: Nishikawa Hiroki , Yoh Kazunori , Enomoto Hirayuki , Iwata Yoshinori , Sakai Yoshiyuki , Kishino Kyohei , Shimono Yoshihiro , Ikeda Naoto , Takashima Tomoyuki , Aizawa Nobuhiro , Takata Ryo , Hasegawa Kunihiro , Koriyama Takashi , Yuri Yukihisa , Nishimura Takashi , Nishiguchi Shuhei , Iijima Hiroko
Published: June 2020

Background and objectives: Few data with regard to the relevance between depression and frailty in chronic liver disease (CLD) patients are currently available. We aimed to elucidate the relationship between frailty and depression as evaluated by the Beck Depression Inventory—2nd edition (BDI-II) in CLD patients (n = 340, median age = 65.0 years). Methods: Frailty was defined as a clinical syndrome in which three or more of the following criteria were met: body weight loss, exhaustion, muscle weakness, slow walking speed and low physical activity. Depressive state was defined as BDI-II score 11 or greater. Results: Robust (frailty score = zero), prefrail (frailty score = one or two) and frailty were identified in 114 (33.5%), 182 (53.5%) and 44 (12.9%). The median BDI-II score was five. Depressive state was identified in 84 patients (24.7%). The median BDI-II scores in patients with robust, prefrail and frail traits were 2, 7 and 12.5 (robust vs. prefrail, p < 0.0001; prefrail vs. robust, p = 0.0003; robust vs. frail, p < 0.0001; overall p < 0.0001). The proportions of depressive state in patients with robust, prefrail and frail traits were 3.51%, 30.77% and 54.55% (robust vs. prefrail, p < 0.0001; prefrail vs. robust, p = 0.0046; robust vs. frail, p < 0.0001; overall p < 0.0001). BDI-II score significantly correlated with frailty score (rs = 0.5855, p < 0.0001). Conclusions: The close correlation between frailty and depression can be found in CLD. Preventing frailty in CLD should be approached both physiologically and psychologically.
Prognostic Significance of ADAM17 for Gastric Cancer Survival: A Meta-Analysis
Authors: Ni Peng , Yu Mingyang , Zhang Rongguang , He Mengya , Wang Haiyan , Chen Shuaiyin , Duan Guangcai
Published: June 2020

Background and objectives: The prognostic role of a disintegrin and metalloproteinase (ADAM) 17 has been widely assessed in gastric cancer. However, the results are inconsistent. We performed a meta-analysis to evaluate the prognostic significance of ADAM17 and its association with clinicopathological parameters. Methods: The databases of PubMed, Web of Science, and Embase were searched for relevant articles published up to April 2020. The reported hazard ratios (HRs) and odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were pooled to evaluate the strength of the association. Stata 12.1 was used to perform statistical analyses. Results: Seven studies, including 1757 patients, were screened for the meta-analysis. Compared with the high ADAM17 expression group, the pooled HR was higher in the low ADAM17 expression group (HR = 2.04, 95% CI 1.66–2.50; I2 = 18.1%; p = 0.299). High ADAM17 expression was also related to the tumor node metastasis (TNM) stages (OR = 4.09, 95% CI 1.85–9.04; I2 = 84.1%; p = 0.000), lymph node metastasis (OR = 3.08, 95% CI 1.13–8.36; I2 = 79.7%; p = 0.007), and ages (OR = 1.65, 95% CI 1.24–2.21; I2 = 0%; p = 0.692) of the gastric patients. Conclusions: This meta-analysis revealed that ADAM17 is a significant biomarker for poor prognosis in gastric cancer.
Evaluation of Surface Integrity in 18CrNiMo7-6 Steel after Multiple Abrasive Waterjet Peening Process
Authors: Zou Yun , Xu Yafeng , Li Jingkai , Liu Shuhao , Wang Dong , Li Yang
Published: June 2020

Abrasive waterjet peening (AWJP) as an important surface strengthening method can effectively improve surface properties. In this study, after multiple AWJP, the distribution of compressive residual stress and roughness on the surface of 18CrNiMo7-6 steel has been evaluated by an X-ray diffraction (XRD) method and a 3D surface topography system, respectively. Compared with the single AWJP, multiple AWJP can obviously increase the surface residual stresses (−1024 MPa to −1455 MPa) and the depth of maximum compressive residual stress (100 μm to 120 μm), as well as make the stress distribution more uniform. In terms of the surface roughness, multiple AWJP influences its uniform distribution and reduces the surface roughness (Sa = 0.69 μm), compared with a single AWJP (Sa = 2.96 μm), due to the smaller shot balls and a uniform deformation during multiple AWJP. In addition, we have studied the effects of multiple AWJP on the hardness of the surface layer. The results show that multiple AWJP increases the hardness by up to 15.9%, compared to the single AWJP. These studies provide useful insight into improving the surface properties of 18CrNiMo7-6 steel by multiple AWJP.
Percolation of Primary Crystals in Cell Walls of Aluminum Alloy Foam via Semi-Solid Route
Authors: Takamatsu Satomi , Kuwahara Takashi , Kochi Ryunosuke , Suzuki Shinsuke
Published: June 2020

Herein, a uniform aluminum alloy foam was fabricated by the addition of TiH2 as a blowing agent to Al-6.4 mass % Si in the semi-solid state and subsequent solidification. This was aimed at propounding the stabilization mechanism of the proposed foaming process. The microscopic images, which were the cross section on the center of the foam etched with Weck’s reagent, showed the primary crystals in the semi-solid state and solidifying segregation surrounding the crystals. Thus, it became evident that the area ratio of primary crystals in the semi-solid state approximately equals to the set solid fraction. According to the percolation theory for the cell wall model, the drainage in the cell walls with primary crystals above the percolation threshold was found to be inhibited. By considering that each cell wall is a flow path of the foam, the percentage of the cell walls with inhibited drainage to all the other cell walls was observed to exceed the percolation threshold of the lattice model (0.33) as per the percolation theory. Therefore, it can be concluded that the primary crystals inhibit drainage in some cell walls, ensuring that the stability of the foam is maintained.
Recent Developments in Ozone Sensor Technology for Medical Applications
Authors: Petani Lisa , Koker Liane , Herrmann Janina , Hagenmeyer Veit , Gengenbach Ulrich , Pylatiuk Christian
Published: June 2020

There is increasing interest in the utilisation of medical gases, such as ozone, for the treatment of herniated disks, peripheral artery diseases, and chronic wounds, and for dentistry. Currently, the in situ measurement of the dissolved ozone concentration during the medical procedures in human bodily liquids and tissues is not possible. Further research is necessary to enable the integration of ozone sensors in medical and bioanalytical devices. In the present review, we report selected recent developments in ozone sensor technology (2016–2020). The sensors are subdivided into ozone gas sensors and dissolved ozone sensors. The focus thereby lies upon amperometric and impedimetric as well as optical measurement methods. The progress made in various areas—such as measurement temperature, measurement range, response time, and recovery time—is presented. As inkjet-printing is a new promising technology for embedding sensors in medical and bioanalytical devices, the present review includes a brief overview of the current approaches of inkjet-printed ozone sensors.
On-Chip Detection of the Biomarkers for Neurodegenerative Diseases: Technologies and Prospects
Authors: Song Chao , Que Suya , Heimer Lucas , Que Long
Published: June 2020

Alzheimer’s disease (AD), Parkinson’s disease (PD) and glaucoma are all regarded as neurodegenerative diseases (neuro-DDs) because these diseases are highly related to the degeneration loss of functions and death of neurons with aging. The conventional diagnostic methods such as neuroimaging for these diseases are not only expensive but also time-consuming, resulting in significant financial burdens for patients and public health challenge for nations around the world. Hence early detection of neuro-DDs in a cost-effective and rapid manner is critically needed. For the past decades, some chip-based detection technologies have been developed to address this challenge, showing great potential in achieving point-of-care (POC) diagnostics of neuro-DDs. In this review, chip-based detection of neuro-DDs’ biomarkers enabled by different transducing mechanisms is evaluated.
PIV-Based Acoustic Pressure Measurements of a Single Bubble near the Elastic Boundary
Authors: Yu Qidong , Xu Zhicheng , Zhao Jing , Zhang Mindi , Ma Xiaojian
Published: June 2020

The objective of this paper was to investigate acoustic pressure waves and the transient flow structure emitted from the single bubble near an elastic boundary based on the particle image velocimetry (PIV). A combination of an electric-spark bubble generator and PIV were used to measure the temporal bubble shapes, transient flow structure, as well as the mid-span deflection of an elastic boundary. Results are presented for three different initial positions near an elastic boundary, which were compared with results obtained using a rigid boundary. A formula relating velocity and pressure was proposed to calculate the acoustic pressure contours surrounding a bubble based on the velocity field of the transient flow structure obtained using PIV. The results show the bubbles near the elastic boundary presented a “mushroom” bubble and an inverted cone bubble. Based on the PIV-measured acoustic pressure contours, a significant pressure difference is found between the elastic boundary and the underside of the bubble, which contributed to the formation of the “mushroom” bubble and inverted cone bubble. Furthermore, the bubbles had opposite migration direction near rigid and elastic boundaries, respectively. In detail, the bubble was repelled away from the elastic boundary and the bubble was attracted by the rigid boundary. The resultant force made up of a Bjerknes force and buoyancy force dominated the migration direction of the bubble.
In Silico Comparison Shows that the Pan-Genome of a Dairy-Related Bacterial Culture Collection Covers Most Reactions Annotated to Human Microbiomes
Authors: Roder Thomas , Wüthrich Daniel , Bär Cornelia , Sattari Zahra , von Ah Ueli , Ronchi Francesca , Macpherson Andrew J. , Ganal-Vonarburg Stephanie C. , Bruggmann Rémy , Vergères Guy
Published: June 2020

The diversity of the human microbiome is positively associated with human health. However, this diversity is endangered by Westernized dietary patterns that are characterized by a decreased nutrient variety. Diversity might potentially be improved by promoting dietary patterns rich in microbial strains. Various collections of bacterial cultures resulting from a century of dairy research are readily available worldwide, and could be exploited to contribute towards this end. We have conducted a functional in silico analysis of the metagenome of 24 strains, each representing one of the species in a bacterial culture collection composed of 626 sequenced strains, and compared the pathways potentially covered by this metagenome to the intestinal metagenome of four healthy, although overweight, humans. Remarkably, the pan-genome of the 24 strains covers 89% of the human gut microbiome’s annotated enzymatic reactions. Furthermore, the dairy microbial collection covers biological pathways, such as methylglyoxal degradation, sulfate reduction, γ-aminobutyric (GABA) acid degradation and salicylate degradation, which are differently covered among the four subjects and are involved in a range of cardiometabolic, intestinal, and neurological disorders. We conclude that microbial culture collections derived from dairy research have the genomic potential to complement and restore functional redundancy in human microbiomes.
Early-Stage Growth Mechanism and Synthesis Conditions-Dependent Morphology of Nanocrystalline Bi Films Electrodeposited from Perchlorate Electrolyte
Authors: Tishkevich Daria , Grabchikov Sergey , Zubar Tatiana , Vasin Denis , Trukhanov Sergei , Vorobjova Alla , Yakimchuk Dmitry , Kozlovskiy Artem , Zdorovets Maxim , Giniyatova Sholpan , Shimanovich Dmitriy , Lyakhov Dmitry , Michels Dominik , Dong Mengge , Gudkova Svetlana , Trukhanov Alex
Published: June 2020

Bi nanocrystalline films were formed from perchlorate electrolyte (PE) on Cu substrate via electrochemical deposition with different duration and current densities. The microstructural, morphological properties, and elemental composition were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray microanalysis (EDX). The optimal range of current densities for Bi electrodeposition in PE using polarization measurements was demonstrated. For the first time, it was shown and explained why, with a deposition duration of 1 s, co-deposition of Pb and Bi occurs. The correlation between synthesis conditions and chemical composition and microstructure for Bi films was discussed. The analysis of the microstructure evolution revealed the changing mechanism of the films’ growth from pillar-like (for Pb-rich phase) to layered granular form (for Bi) with deposition duration rising. This abnormal behavior is explained by the appearance of a strong Bi growth texture and coalescence effects. The investigations of porosity showed that Bi films have a closely-packed microstructure. The main stages and the growth mechanism of Bi films in the galvanostatic regime in PE with a deposition duration of 1–30 s are proposed.
Carbon Dot Nanoparticles Exert Inhibitory Effects on Human Platelets and Reduce Mortality in Mice with Acute Pulmonary Thromboembolism
Authors: Lee Tzu-Yin , Jayakumar Thanasekaran , Thanasekaran Pounraj , Lin King-Chuen , Chen Hui-Min , Veerakumar Pitchaimani , Sheu Joen-Rong
Published: June 2020

The inhibition of platelet activation is considered a potential therapeutic strategy for the treatment of arterial thrombotic diseases; therefore, maintaining platelets in their inactive state has garnered much attention. In recent years, nanoparticles have emerged as important players in modern medicine, but potential interactions between them and platelets remain to be extensively investigated. Herein, we synthesized a new type of carbon dot (CDOT) nanoparticle and investigated its potential as a new antiplatelet agent. This nanoparticle exerted a potent inhibitory effect in collagen-stimulated human platelet aggregation. Further, it did not induce cytotoxic effects, as evidenced in a lactate dehydrogenase assay, and inhibited collagen-activated protein kinase C (PKC) activation and Akt (protein kinase B), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) phosphorylation. The bleeding time, a major side-effect of using antiplatelet agents, was unaffected in CDOT-treated mice. Moreover, our CDOT could reduce mortality in mice with ADP-induced acute pulmonary thromboembolism. Overall, CDOT is effective against platelet activation in vitro via reduction of the phospholipase C/PKC cascade, consequently suppressing the activation of MAPK. Accordingly, this study affords the validation that CDOT has the potential to serve as a therapeutic agent for the treatment of arterial thromboembolic disorders
Intra-Cycle Elastic Nonlinearity of Nitrogen-Doped Carbon Nanotube/Polymer Nanocomposites under Medium Amplitude Oscillatory Shear (MAOS) Flow
Authors: Kamkar Milad , Sadeghi Soheil , Arjmand Mohammad , Aliabadian Ehsan , Sundararaj Uttandaraman
Published: June 2020

This study seeks to unravel the effect of carbon nanotube’s physical and chemical features on the final electrical and rheological properties of polymer nanocomposites thereof. Nitrogen-doped carbon nanotubes (N-CNTs) were synthesized over two different types of catalysts, i.e., Fe and Ni, employing chemical vapor deposition. Utilizing this technique, we were able to synthesize N-CNTs with significantly different structures. As a result, remarkable differences in the network structure of the nanotubes were observed upon mixing the N-CNTs in a polyvinylidene fluoride (PVDF) matrix, which, in turn, led to drastically different electrical and rheological properties. For instance, no enhancement in the electrical conductivity of poorly-dispersed (N-CNT)Ni/PVDF samples was observed even at high nanotube concentrations, whereas (N-CNT)Fe/PVDF nanocomposites exhibited an insulative behavior at 1.0 wt%, a semi-conductive behavior at 2.0 wt%, and a conductive behavior at 2.7 wt%. In terms of rheology, the most substantial differences in the viscoelastic behavior of the systems were distinguishable in the medium amplitude oscillatory shear (MAOS) region. The stress decomposition method combined with the evaluation of the elastic and viscous third-order Chebyshev coefficients revealed a strong intra-cycle elastic nonlinearity in the MAOS region for the poorly-dispersed systems in small frequencies; however, the well-dispersed systems showed no intra-cycle nonlinearity in the MAOS region. It was shown that the MAOS elastic nonlinearity of poorly-dispersed systems stems from the confinement of N-CNT domains between the rheometer’s plates for small gap sizes comparable with the size of the agglomerates. Moreover, the intra-cycle elastic nonlinearity of poorly-dispersed systems is frequency-dependent and vanished at higher frequencies. The correlation between the microstructure and viscoelastic properties under large shear deformations provides further guidance for the fabrication of high-performance 3D-printed electrically conductive nanocomposites with precisely controllable final properties for engineering applications.
Lattice Rayleigh Anomaly Associated Enhancement of NH and CH Stretching Modes on Gold Metasurfaces for Overtone Detection
Authors: R. Dadadzhanov Daler , A. Vartanyan Tigran , Karabchevsky Alina
Published: June 2020

Molecular overtones stretching modes that occupy the near-infrared (NIR) are weak compared to the fundamental vibrations. Here we report on the enhancement of absorption by molecular vibrations overtones via electromagnetic field enhancement of plasmonic nanoparallelepipeds comprising a square lattice. We explore numerically, using finite element method (FEM), gold metasurfaces on a transparent dielectric substrate covered by weakly absorbing analyte supporting N-H and C-H overtone absorption bands around 1.5 μ m and around 1.67 μ m, respectively. We found that the absorption enhancement in N-H overtone transition can be increased up to the factor of 22.5 due to the combination of localized surface plasmon resonance in prolonged nanoparticles and lattice Rayleigh anomaly. Our approach may be extended for sensitive identification of other functional group overtone transitions in the near-infrared spectral range.
Cocoa Polyphenols and Gut Microbiota Interplay: Bioavailability, Prebiotic Effect, and Impact on Human Health
Authors: Sorrenti Vincenzo , Ali Sawan , Mancin Laura , Davinelli Sergio , Paoli Antonio , Scapagnini Giovanni
Published: June 2020

Cocoa and its products are rich sources of polyphenols such as flavanols. These compounds exert antioxidant and anti-inflammatory activities, accountable for cocoa health-promoting effects. However, cocoa polyphenols are poorly absorbed in the intestine, and most of them cannot reach the systemic circulation in their natural forms. Instead, their secondary bioactive metabolites are bioavailable, enter the circulation, reach the target organs, and exhibit their activities. In fact, once reaching the intestine, cocoa polyphenols interact bidirectionally with the gut microbiota. These compounds can modulate the composition of the gut microbiota exerting prebiotic mechanisms. They enhance the growth of beneficial gut bacteria, such as Lactobacillus and Bifidobacterium, while reducing the number of pathogenic ones, such as Clostridium perfringens. On the other hand, bioactive cocoa metabolites can enhance gut health, displaying anti-inflammatory activities, positively affecting immunity, and reducing the risk of various diseases. This review aims to summarize the available knowledge of the bidirectional interaction between cocoa polyphenols and gut microbiota with their various health outcomes.
Low Vitamin B12 and Lipid Metabolism: Evidence from Pre-Clinical and Clinical Studies
Authors: Boachie Joseph , Adaikalakoteswari Antonysunil , Samavat Jinous , Saravanan Ponnusamy
Published: June 2020

Obesity is a worldwide epidemic responsible for 5% of global mortality. The risks of developing other key metabolic disorders like diabetes, hypertension and cardiovascular diseases (CVDs) are increased by obesity, causing a great public health concern. A series of epidemiological studies and animal models have demonstrated a relationship between the importance of vitamin B12 (B12) and various components of metabolic syndrome. High prevalence of low B12 levels has been shown in European (27%) and South Indian (32%) patients with type 2 diabetes (T2D). A longitudinal prospective study in pregnant women has shown that low B12 status could independently predict the development of T2D five years after delivery. Likewise, children born to mothers with low B12 levels may have excess fat accumulation which in turn can result in higher insulin resistance and risk of T2D and/or CVD in adulthood. However, the independent role of B12 on lipid metabolism, a key risk factor for cardiometabolic disorders, has not been explored to a larger extent. In this review, we provide evidence from pre-clinical and clinical studies on the role of low B12 status on lipid metabolism and insights on the possible epigenetic mechanisms including DNA methylation, micro-RNA and histone modifications. Although, there are only a few association studies of B12 on epigenetic mechanisms, novel approaches to understand the functional changes caused by these epigenetic markers are warranted.
Prey-Related Asphyxiation in Harbor Porpoises (Phocoena phocoena) along the U.S. West Coast: Importance of American Shad (Alosa sapidissima) on Adult Female Harbor Porpoise Mortality
Authors: Elliser Cindy R. , Calambokidis John , D’Alessandro Dalin N. , Duffield Deborah A. , Huggins Jessica L. , Rice James , Szczepaniak Isidore , Webber Marc
Published: June 2020

Harbor porpoise (Phocoena phocoena) diets are predominantly comprised of small fish species (<30 cm) and squid. However, predation on larger species (up to 63 cm) occurs, raising the question of increased risk of asphyxiation associated with this behavior. Literature was reviewed and stranding data from 1983 to 2020 from the U.S. West Coast (including California, Oregon and Washington) were searched for cases of prey-related asphyxiation of harbor porpoises and analyzed in relation to age, sex, reproductive status and prey species. Twenty-nine cases were documented. Twenty-seven cases involved large prey; non-native American shad caused the asphyxiation in 87% of the cases where the prey species was identified. The majority (92%) of harbor porpoises were females, and at least 83.3% were pregnant or recently post-partum. Reproductively active females may be more likely to attempt potentially risky behavior in order to compensate for their increased energetic needs. Increasing numbers of non-native American shad may pose a unique danger in this region for harbor porpoises not adapted to deal with the challenges of that prey. This may be a cause for concern, as there is likely an interaction between location, age and reproductive status on the diet composition and foraging strategies of harbor porpoises.
Relations between Clifford Algebra and Dirac Matrices in the Presence of Families
Authors: Lukman Dragan , Komendyak Mickael , Mankoč Borštnik Norma Susana
Published: June 2020

The internal degrees of freedom of fermions are in the spin-charge-family theory described by the Clifford algebra objects, which are superposition of an odd number of γ a ’s. Arranged into irreducible representations of “eigenvectors” of the Cartan subalgebra of the Lorentz algebra S a b ( = i 2 γ a γ b | a ≠ b ) these objects form 2 d 2 − 1 families with 2 d 2 − 1 family members each. Family members of each family offer the description of all the observed quarks and leptons and antiquarks and antileptons, appearing in families. Families are reachable by S ˜ a b = 1 2 γ ˜ a γ ˜ b | a ≠ b . Creation operators, carrying the family member and family quantum numbers form the basis vectors. The action of the operators γ a ’s, S a b , γ ˜ a ’s and S ˜ a b , applying on the basis vectors, manifests as matrices. In this paper the basis vectors in d = ( 3 + 1 ) Clifford space are discussed, chosen in a way that the matrix representations of γ a and of S a b coincide for each family quantum number, determined by S ˜ a b , with the Dirac matrices. The appearance of charges in Clifford space is discussed by embedding d = ( 3 + 1 ) space into d = ( 5 + 1 ) -dimensional space. The achievements and predictions of the spin-charge-family theory is also shortly presented.
Prolactin and Estradiol are Epigenetic Modulators in Bovine Mammary Epithelial Cells during Staphylococcus aureus Infection
Authors: Salgado-Lora María Guadalupe , Medina-Estrada Ivan , López-Meza Joel Edmundo , Ochoa-Zarzosa Alejandra
Published: June 2020

Changes in the levels of reproductive hormones compromise the bovine innate immune response (IIR). Changes in 17β-estradiol (E2) and prolactin (bPRL) levels affect the IIR of bovine mammary epithelial cells (bMECs), the target tissue of these hormones. In this work, we explored the effect of the combined hormones on bMEC IIR during Staphylococcus aureus infection, and if they can modulate epigenetic marks. By gentamicin protection assays, we determined that combined hormones (bPRL (5 ng/mL) and E2 (50 pg/mL)] decrease S. aureus internalization into bMECs (~50%), which was associated with a reduction in integrin α5β1 membrane abundance (MA) (~80%) determined by flow cytometry. Additionally, combined hormones increased Toll-like receptor 2 (TLR2) MA (~25%). By RT-qPCR, we showed that combined hormones induce the expression of pro- and anti-inflammatory cytokine genes, as well as up-regulate antimicrobial peptide gene expression. The combined hormones induced H3K9Ac at 12 h of treatment, which coincides with the reduction in histone deacetylase (HDAC, ~15%) activity. In addition, hormones increased the H3K9me2 mark at 12 h, which correlates with a reduction in the expression of KDM4A. In conclusion, bPRL and E2 modulate the IIR of bMECs, an effect that can be related to the regulation of histone H3 modifications such as H3K9Ac and H3K9me2.
Multidrug Resistance (MDR) and Collateral Sensitivity in Bacteria, with Special Attention to Genetic and Evolutionary Aspects and to the Perspectives of Antimicrobial Peptides—A Review
Authors: Fodor András , Abate Birhan Addisie , Deák Péter , Fodor László , Gyenge Ervin , Klein Michael G. , Koncz Zsuzsanna , Muvevi Josephat , Ötvös László , Székely Gyöngyi , Vozik Dávid , Makrai László
Published: June 2020

Antibiotic poly-resistance (multidrug-, extreme-, and pan-drug resistance) is controlled by adaptive evolution. Darwinian and Lamarckian interpretations of resistance evolution are discussed. Arguments for, and against, pessimistic forecasts on a fatal “post-antibiotic era” are evaluated. In commensal niches, the appearance of a new antibiotic resistance often reduces fitness, but compensatory mutations may counteract this tendency. The appearance of new antibiotic resistance is frequently accompanied by a collateral sensitivity to other resistances. Organisms with an expanding open pan-genome, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae, can withstand an increased number of resistances by exploiting their evolutionary plasticity and disseminating clonally or poly-clonally. Multidrug-resistant pathogen clones can become predominant under antibiotic stress conditions but, under the influence of negative frequency-dependent selection, are prevented from rising to dominance in a population in a commensal niche. Antimicrobial peptides have a great potential to combat multidrug resistance, since antibiotic-resistant bacteria have shown a high frequency of collateral sensitivity to antimicrobial peptides. In addition, the mobility patterns of antibiotic resistance, and antimicrobial peptide resistance, genes are completely different. The integron trade in commensal niches is fortunately limited by the species-specificity of resistance genes. Hence, we theorize that the suggested post-antibiotic era has not yet come, and indeed might never come.
Naturally Acquired Humoral Immunity against Malaria Parasites in Non-Human Primates from the Brazilian Amazon, Cerrado and Atlantic Forest
Authors: Monteiro Eliana Ferreira , Fernandez-Becerra Carmen , Araujo Maisa da Silva , Messias Mariluce Rezende , Ozaki Luiz Shozo , Duarte Ana Maria Ribeiro de Castro , Bueno Marina Galvão , Catao-Dias Jose Luiz , Chagas Carolina Romeiro Fernandes , Mathias Bruno da Silva , Santos Mayra Gomes dos , Santos Stéfanie Vanessa , Holcman Marcia Moreira , Souza Julio Cesar de , Kirchgatter Karin
Published: June 2020

Non-human primates (NHPs) have been shown to be infected by parasites of the genus Plasmodium, the etiological agent of malaria in humans, creating potential risks of zoonotic transmission. Plasmodium brasilianum, a parasite species similar to P. malariae of humans, have been described in NHPs from Central and South America, including Brazil. The merozoite surface protein 1 (MSP1), besides being a malaria vaccine candidate, is highly immunogenic. Due to such properties, we tested this protein for the diagnosis of parasite infection. We used recombinant proteins of P. malariae MSP1, as well as of P. falciparum and P. vivax, for the detection of antibodies anti-MSP1 of these parasite species, in the sera of NHPs collected in different regions of Brazil. About 40% of the NHP sera were confirmed as reactive to the proteins of one or more parasite species. A relatively higher number of reactive sera was found in animals from the Atlantic Forest than those from the Amazon region, possibly reflecting the former more intense parasite circulation among NHPs due to their proximity to humans at a higher populational density. The presence of Plasmodium positive NHPs in the surveyed areas, being therefore potential parasite reservoirs, needs to be considered in any malaria surveillance program.
Body, Soul, and Spirit: An Explorative Qualitative Study of Anthroposophic Meditation and Spiritual Practice
Authors: Sparby Terje
Published: June 2020

This article presents the results of a qualitative study of Anthroposophic meditation, which arose in the German-speaking world in the early 20th Century focusing on cognition, self-development, and pro-social action. The objective was to explore this previously unstudied form of meditation. The current sample (N = 30) consists of long-term practitioners of Anthroposophic meditation. Semi-structured interviews, focusing on demographics, background, and phenomenology and interpretation, were conducted with these practitioners. The material gathered was investigated using thematic analysis. Seven main themes were found: Self, cognition, perception, affect, sleep, embodiment, and environment, and, among these, 32 subthemes. Potential avenues for further research are outlined. Some of these overlap with current approaches to meditation while others represent new areas of inquiry: Personal development with a focus on strengthening the self, introspection or contemplative inquiry, sensed presences, the experience of phenomenological atmospheres, consciousness in the sleep state, embodied aspects of meditation experience, the relationship between practice and daily life, and meditation challenges.
Neural Networks and Betting Strategies for Tennis
Authors: Candila Vincenzo , Palazzo Lucio
Published: June 2020

Recently, the interest of the academic literature on sports statistics has increased enormously. In such a framework, two of the most significant challenges are developing a model able to beat the existing approaches and, within a betting market framework, guarantee superior returns than the set of competing specifications considered. This contribution attempts to achieve both these results, in the context of male tennis. In tennis, several approaches to predict the winner are available, among which the regression-based, point-based and paired comparison of the competitors’ abilities play a significant role. Contrary to the existing approaches, this contribution employs artificial neural networks (ANNs) to forecast the probability of winning in tennis matches, starting from all the variables used in a large selection of the previous methods. From an out-of-sample perspective, the implemented ANN model outperforms four out of five competing models, independently of the considered period. For what concerns the betting perspective, we propose four different strategies. The resulting returns on investment obtained from the ANN appear to be more broad and robust than those obtained from the best competing model, irrespective of the betting strategy adopted.