bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre-Analytical and Clinical Validation of a Dried Blood Spot Assay for Asymmetric Dimethylarginine and L-Arginine
Authors: Hannemann Juliane , Roskam Thore I. , Eilermann Ina , Siques Patricia , Brito Julio , Böger Rainer
Published: April 2020

Asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) synthesis. It is a risk marker for cardiovascular events and mortality in patients with cardiometabolic diseases and in population-based studies. Plasma or serum analysis of ADMA may be hampered by pre-analytical sample handling. We validated a dried blood spot (DBS) assay for ADMA and L-arginine and show here that this assay has excellent variabilities and reproducibilities. Filter paper is impregnated with the arginase inhibitor nor-NOHA (Nω-hydroxy-nor-Arginine) to avoid L-arginine degradation. Clinical validation of this DBS assay confirms elevated ADMA concentration in hemodialysis patients as compared to healthy controls, higher ADMA concentrations in men versus women, and elevated L-arginine concentration in subjects supplemented with L-arginine. The DBS assay was used in a cohort study involving 100 primarily healthy subjects in the Andean region to assess the impact of chronic intermittent hypoxia on ADMA and L-arginine; ADMA DBS concentration at sea level was prospectively associated with pulmonary hypertension after six months of exposure to 3500 m. In a cohort of 753 individuals, L-arginine/ADMA ratio significantly decreased with increasing number of traditional cardiovascular risk factors. Analysis of ADMA and L-arginine in DBS is a reliable and reproducible method for quantitation of these markers in field studies.
Multi-Performance Characteristics of AA5052 + 10% SiC Surface Composite by Friction Stir Processing
Authors: Kraiklang Rungwasun , Onwong Jariyaporn , Santhaweesuk Charuayporn
Published: April 2020

In this paper, optimization of the fabrication parameters of an aluminum surface composite with respect to tensile strength and tool wear rate is reported. The surface layer was reinforced with SiC particles to improve the tribological properties of AA-5052. The Taguchi design with orthogonal array L8 was used for the experimental design, which included three processing parameters: the number of passes, rotational speed, and traversal speed. The experiment used optimal fabrication parameter searching to produce a multi-response prediction of both the tensile strength and tool wear rate. The experimental result was determined by grey relational analysis for multi-performance characteristics. Afterward, the prediction result of the optimal fabrication parameters was confirmed by repeated experiments to confirm the selection of optimal process parameters. The results revealed that the optimal fabrication parameters for multi-performance characteristics are two passes, rotational speed of 1000 revolutions per minute (RPM), and traversal speed of 30 mm/min (condition N2R1T2). These showed high tensile strength (229.90 MPa), low tool wear rate (0.0851), and a uniform distribution of SiC particles in the matrix. In addition, grey relational analysis showed that the parameter priority was 51.68% for rotational speed (the most significant process parameter), 36.18% for transversal speed, and 7.05% for the number of passes. Therefore, the grey-based orthogonal array Taguchi method can optimize multi-performance characteristics through the setting of process parameters for friction stir processing of an aluminum surface composite.
Ring-Shaped Surface Microstructures for Improved Lubrication Performance of Joint Prostheses
Authors: Drescher Philipp , Oldorf Paul , Dreier Tim , Schnell Georg , Peters Rigo , Seitz Hermann
Published: April 2020

The microstructuring of surfaces is a highly researched field that is aimed at enhancing the tribological behavior of sliding surfaces such as artificial joints, which are subject to wear. Lubrication of the joint interface plays a key role in the wear process, although the mechanisms of lubrication are quite complex. In order to improve the lubrication, the surfaces of the articulating components can be modified by pulsed femtosecond-laser microstructuring. Through microstructuring, the apparent dynamic viscosity of the synovial fluid between the artificial joint can be increased due to its non-Newtonian properties. This may lead to better hydrodynamic lubrication and, therefore, reduced particle abrasion. Femtosecond laser-induced microstructures were investigated in a modified rheometer setup featuring a reduced gap size in order to reproduce and measure the interface between fluid and implant surface more accurately. As a test fluid, a synovial fluid substitute was used. The study has shown that an increase in the viscosity of the synovial fluid substitute can be achieved by microstructuring. Compared to a smooth implant surface, the apparent viscosity of the synovial fluid substitute increased by over 30% when ring-shaped microstructures of 100 µm diameter with an aspect ratio of 0.66 were implemented.
Active Actuating of a Simply Supported Beam with the Flexoelectric Effect
Authors: Fan Mu , Min Hequn
Published: April 2020

Piezoelectric materials with the electro-mechanical coupling effect have been widely utilized in sensors, dampers, actuators, and so on. Engineering structures with piezoelectric actuators and sensors have provided great improvement in terms of vibration and noise reduction. The flexoelectric effect—which describes the coupling effect between the polarization gradient and strain, and between the strain gradient and electric polarization in solids—has a fourth-rank order tensor electro-mechanical coupling coefficient, and in principle makes the flexoelectricity existing in all insulating materials and promises an even wider application potential in vibration and noise control. In the presented work, a flexoelectric actuator was designed to actuate a simply supported beam. The electric field gradient was generated by an atomic force microscopy probe. Flexoelectric control force and moment components could be induced within the flexoelectric control layer. As flexoelectricity is size-dependent, the key parameters that could affect the actuating effect were examined in case studies. Analytical results showed that the induced flexoelectric control moment was strongly concentrated at the probe location. The controllable transverse displacement of the simply supported beam was calculated with the modal expansion method. It was found that the controllable transverse displacement was dependent on the probe location as well.
Application of Atomic Force Microscope to Investigate the Surface Micro-Adhesion Properties of Asphalt
Authors: Ji Xiaoping , Li Jia , Zhai Xugang , Zou Haiwei , Chen Bo
Published: April 2020

The surface energy and bonding coefficient of asphalt are important factors that affect the adhesion performance of asphalt/aggregate. In this study, the micro-bee-like-structure of asphalt and force curves between the microscope-probe and asphalt were measured via atomic force microscopy (AFM). To investigate the influence of asphalt properties on micro-adhesion of asphalt, five types of asphalt were used in four states: original, aged at 163 °C, immersed in water and added anti-stripping agent. The results demonstrate that the surface energy of grade 90 asphalt is greater than that of grade 70 asphalt when oil source is the same and that of modified asphalt is greater than matrix asphalt. The surface energies and bonding coefficients of asphalts decreased after aging and immersion. The surface energies of asphalts were greatly improved by adding anti-stripping agent and the bonding coefficients of the asphalts increased by 5.04–37.14% after adding an anti-stripping agent.
Optical, Structural, and Crystal Defects Characterizations of Dip Synthesized (Fe-Ni) Co-Doped ZnO Thin Films
Authors: Alsaad Ahmad M. , Ahmad Ahmad A. , Al-Bataineh Qais M. , Bani-Salameh Areen A. , Abdullah Hadeel S. , Qattan Issam A. , Albataineh Zaid M. , Telfah Ahmad D.
Published: April 2020

Sol-gel technique is used to synthesize as-grown zinc oxide (ZnO) and iron-nickel (Fe-Ni) co-doped ZnO thin films deposited on glass substrates using dip coating technique. The structural properties and crystal imperfections of as-prepared thin films are investigated. We performed the structural analysis of films using X-ray diffraction (XRD). The XRD analysis reveal that the as-prepared films exhibit wurtzite structure. Furthermore, XRD-line profile analysis is performed to study the correlation between structural properties and imperfections of the nanocomposite thin films. The crystallite size and microstrains parameters are predicted using the Williamson–Hall method. We found that the crystallites size increases as the co-doped (Fe-Ni) concentration is increased. However, microstrains of the nanocomposite films decreases as (Fe-Ni) concentration is increased. The optical properties of the (Fe-Ni) co-doped nanocomposite films are investigated by performing UV-Vis (250 nm–700 nm) spectrophotometer measurements. We found that as the (Fe-Ni) concentration level is steadily increased, transmittance of the undoped ZnO thin films is decreased. Remarkably, refractive index of undoped ZnO thin films is found to exhibit values extending from 1.55 to1.88 that would increase as (Fe-Ni) concentration is increased.
Effect of Mo Addition on the Chemical Corrosion Process of SiMo Cast Iron
Authors: Stawarz Marcin , Nuckowski Paweł M.
Published: April 2020

The study was carried out to evaluate five SiMo cast iron grades and their resistance to chemical corrosion at elevated temperature. Corrosion tests were carried out under conditions of an actual cyclic operation of a retort coal-fired boiler. The duration of the study was 3840 h. The range of temperature changes during one cycle was in the range of 300–650 °C. Samples of SiMo cast iron with Si content at the level of 5% and variable Mo content in the range 0%–2.5% were used as the material for the study. The examined material was subjected to preliminary metallographic analysis using scanning microscopy and an Energy dispersive spectroscopy (EDS) system. The chemical composition was determined on the basis of a Leco spectrometer and a Leco carbon and sulfur analyzer. The examination of the oxide layer was carried out with the use of Scanning electron microscope (SEM), EDS, and X-ray diffraction (XRD) methods. It was discovered that, in the analyzed alloys, oxide layers consisting of Fe2O3, Fe3O4, SO2, and Fe2SiO4 were formed. The analyzed oxide layers were characterized by high adhesion to the substrate material, and their total thickness was about 20 μm.
Pullout Behavior of Bundled Aramid Fiber in Fiber-Reinforced Cementitious Composite
Authors: Kanakubo Toshiyuki , Echizen Saki , Wang Jin , Mu Yu
Published: April 2020

The tensile performance of fiber-reinforced cementitious composite (FRCC) after first matrix cracking is characterized by a tensile stress–crack width relationship called the bridging law. The bridging law can be obtained by an integral calculus of forces carried by individual bridging fibers considering the effect of the fiber inclination angle. The main objective of this study is to investigate experimentally and evaluate the pullout behavior of a single aramid fiber, which is made with a bundling of original yarns of aramid fiber. The bundled aramid fiber has a nonsmooth surface, and it is expected to have good bond performance with the matrix. The test variables in the pullout test are the thickness of the matrix and the inclined angle of the fiber. From the test results, the pullout load–slip curves showed that the load increases lineally until maximum load, after which it decreases gradually. The maximum pullout load and slip at the maximum load increase as the embedded length of the fiber becomes larger. The pullout load–crack width relationship is modeled by a bilinear model, and the bridging law is calculated. The calculated result shows good agreement with the experimental curves obtained by the uniaxial tension test of aramid–FRCC.
Synthesis and Characterization of Hydrogenated Diamond-Like Carbon (HDLC) Nanocomposite Films with Metal (Ag, Cu) Nanoparticles
Authors: Koutsokeras Loukas , Constantinou Marios , Nikolaou Petros , Constantinides Georgios , Kelires Pantelis
Published: April 2020

In this work, the synthesis and characterization of hydrogenated diamond-like carbon (HDLC) nanocomposite thin films with embedded metallic Ag and Cu nanoparticles (NPs) are studied. These nanocomposite films were deposited using a hybrid technique with independent control over the carbon and metal sources. The metallic nanoparticles were directly deposited from the gas phase, avoiding surface diffusion of metal species on the deposition surface. The structural features, surface topography and optical properties of pure and nanocomposite HDLC films are studied and the effect of metal introduction into the carbon matrix is discussed. The interactions between the carbon ion beam and the NPs are considered and it is demonstrated that the nanocomposite HDLC:metal films, especially for Cu NPs, can retain the transparency level of the pure HDLC, by limiting the interactions between metal and carbon during deposition.
Carbon Fiber/Polyether Ether Ketone (CF/PEEK) Implants Allow for More Effective Radiation in Long Bones
Authors: Laux Christoph J. , Villefort Christina , Ehrbar Stefanie , Wilke Lotte , Guckenberger Matthias , Müller Daniel A.
Published: April 2020

Background: Metallic implants show dose-modulating effects in radiotherapy and complicate its computed tomography (CT)-based planning. Dose deviations might not only affect the surrounding tissues due to backscattering and inadvertent dose increase but might also compromise the therapeutic effect to the target lesion due to beam attenuation. Later on, follow-up imaging is often obscured by metallic artefacts. Purposes: This study investigates the dosimetric impact of titanium and radiolucent carbon fiber/polyether ether ketone (CF/PEEK) implants during adjuvant radiation therapy in long bones. (1) Does the use of CF/PEEK implants allow for a more homogenous application of radiation? (2) Is the dose delivery to the target volume more efficient when using CF/PEEK implants? (3) Do CF/PEEK implants facilitate CT-based radiation therapy planning? Materials and methods: After CT-based planning, bone models of six ovine femora were irradiated within a water phantom in two immersion depths to simulate different soft-tissue envelopes. Plates and intramedullary nails of both titanium and CF/PEEK were investigated. Radiation dosage and distribution patterns were mapped using dosimetry films. Results: First, the planned implant-related beam attenuation was lower for the CF/PEEK plate (1% vs. 5%) and the CF/PEEK nail (2% vs. 9%) than for corresponding titanium implants. Secondly, the effective decrease of radiation dosage behind the implants was noticeably smaller when using CF/PEEK implants. The radiation dose was not significantly affected by the amount of surrounding soft tissues. A significant imaging artefact reduction was seen in all CF/PEEK models. Conclusion: CF/PEEK implants lead to a more reliable and more effective delivery of radiation dose to an osseous target volume. With regard to radiation therapy, the use of CF/PEEK implants appears to be particularly beneficial for intramedullary nails.
Electrochemical and Biological Performance of Biodegradable Polymer Coatings on Ti6Al7Nb Alloy
Authors: Kajzer Wojciech , Szewczenko Janusz , Kajzer Anita , Basiaga Marcin , Kaczmarek Marcin , Antonowicz Magdalena , Jaworska Joanna , Jelonek Katarzyna , Orchel Arkadiusz , Nowińska Katarzyna , Kasperczyk Janusz
Published: April 2020

The inhibition of the corrosion of metal implants is still a challenge. This study aimed to increase the corrosion resistance of Ti6Al7Nb alloy implants through surface modification, including grinding, sandblasting, and anodic oxidation followed by the deposition of a polymer coating. The aim of the work was to determine the influence of biodegradable polymer coatings on the physico-chemical properties of a Ti6Al7Nb alloy used for short-term implants. Biodegradable coatings prepared from poly(glycolide-caprolactone) (P(GCap)), poly(glycolide ε-caprolactone-lactide) (P(GCapL)), and poly(lactide-glycolide) (PLGA) were applied in the studies. The dip-coating method with three cycles of dipping was applied. Corrosion resistance was assessed on the basis of potentiodynamic studies. The studies were carried out on samples after 30, 60, and 90 days of exposure to Ringer’s solution. Surface topography, wettability, and cytotoxicity studies were also carried out. The degradation process of the base material was evaluated on the basis of the mass density of the metal ions released to the solution. The results indicated the influence of the coating type on corrosion resistance. In addition, a beneficial effect of the polymer coating on the reduction of the density of the released metal ions was found, as compared to the samples without polymer coatings. The obtained results provide basic knowledge for the development of polymer coatings enriched with an active substance. The presence of ciprofloxacin in the coating did not reduce the corrosion resistance of the metal substrate. Moreover, the cytotoxicity test using the extract dilution method demonstrated that the implants’ coatings are promising for further in vitro and in vivo studies.
Orientation-Dependent Deformation Behavior of 316L Steel Manufactured by Laser Metal Deposition and Casting under Local Scratch and Indentation Load
Authors: Pöhl Fabian , Hardes Corinna , Scholz Felicitas , Frenzel Jan
Published: April 2020

This study analyzes the local deformation behavior of austenitic stainless steel 316L, manufactured conventionally by casting and additively by laser metal deposition (LMD). We produced directionally solidified 316L specimens with most grains showing (001) orientations parallel to the longitudinal specimen axis. We conducted nanoindentation and scratch experiments for local mechanical characterization and topography measurements (atomic force microscopy and confocal laser scanning microscopy) of indentation imprints and residual scratch grooves for the analysis of the deformation behavior and, in particular, of the pile-up behavior. The local mechanical properties and deformation behavior were correlated to the local microstructure investigated by scanning electron microscopy with energy dispersive X-ray spectroscopy and electron backscatter diffraction analysis. The results show that the local mechanical properties, deformation behavior, and scratch resistance strongly depend on the crystallographic orientation. Nearly (001)-oriented grains parallel to the surface show the lowest hardness, followed by an increasing hardness of nearly (101)- and (111)-oriented grains. Consequently, scratch depth is the greatest for nearly (001)-oriented grains followed by (101) and (111) orientations. This tendency is seen independently of the analyzed manufacturing route, namely Bridgman solidification and laser metal deposition. In general, the laser metal deposition process leads to a higher strength and hardness, which is mainly attributed to a higher dislocation density. Under the investigated loading conditions, the cellular segregation substructure is not found to significantly and directly change the local deformation behavior during indentation and scratch testing.
Polydopamine-Modified Al2O3/Polyurethane Composites with Largely Improved Thermal and Mechanical Properties
Authors: Du Ruikui , He Li , Li Peng , Zhao Guizhe
Published: April 2020

Alumina/polyurethane composites were prepared via in situ polymerization and used as thermal interface materials (TIMs). The surface of alumina particles was modified using polydopamine (PDA) and then evaluated via Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), and Raman spectroscopy (Raman). Scanning electron microscope (SEM) images showed that PDA-Al2O3 has better dispersion in a polyurethane (PU) matrix than Al2O3. Compared with pure PU, the 30 wt% PDA-Al2O3/PU had 95% more Young’s modulus, 128% more tensile strength, and 76% more elongation at break than the pure PU. Dynamic mechanical analysis (DMA) results showed that the storage modulus of the 30 wt% PDA-Al2O3/PU composite improved, and the glass transition temperature (Tg) shifted to higher temperatures. The thermal conductivity of the 30 wt% PDA-Al2O3/PU composite increased by 138%. Therefore, the results showed that the prepared PDA-coated alumina can simultaneously improve both the mechanical properties and thermal conductivity of PU.
Possibility Measure of Accepting Statistical Hypothesis
Authors: Hung Jung-Lin , Chen Cheng-Che , Lai Chun-Mei
Published: April 2020

Taking advantage of the possibility of fuzzy test statistic falling in the rejection region, a statistical hypothesis testing approach for fuzzy data is proposed in this study. In contrast to classical statistical testing, which yields a binary decision to reject or to accept a null hypothesis, the proposed approach is to determine the possibility of accepting a null hypothesis (or alternative hypothesis). When data are crisp, the proposed approach reduces to the classical hypothesis testing approach.
In Situ Gel Loaded with Chitosan-Coated Simvastatin Nanoparticles: Promising Delivery for Effective Anti-Proliferative Activity against Tongue Carcinoma
Authors: Kurakula Mallesh , Naveen N. Raghavendra
Published: April 2020

The goal of this study is to develop optimized chitosan-coated Simvastatin (SIM) nanoparticles (NPs) loaded in an in situ gel (ISG) formulation via a face-centered central composite design (FCCCD). Coated SIM-NPs were doped with Quercetin (QRC) using a modified nanoprecipitation method. The concentrations of poloxamer 188 (A) and chitosan (B) at five different levels, plus/minus alpha (+1.414 and −1.414: axial points), plus/minus 1 (factorial points) and the center point were optimized for particle size (PS-Y1), entrapment efficacy (EE-Y2) and stability index (SI-Y3). Based on the desirability approach, a formulation containing poloxamer 188 0.24% and chitosan 0.43% renders the prerequisites of optimum formulation for preparing SIM–QRC NP-loaded ISG. Scanning microscopy showed spherical SIM-NPs, indicating monodispersity in the range of 0.50 ± 0.04 nm with a charge of +32.42 mV. The optimized formulation indicated the highest EE 79.67% and better stability at 4 °C. Drug release from SIM–QRC NP-loaded ISG was slower to plateau by up to 96 h and, at the end of 168 h, only 65.12% of SIM was released in a more controlled manner in comparison to SIM–QRC NPs and plain SIM. ISG formulation showed a considerable increase in apoptosis occurrence through caspase-3 mediation and it also enhanced the tumor suppressor protein levels. Enhanced biological activity of SIM was observed due to QRC enabling promising drug and polymer synergistic interaction. The proposed formulation can provide a breakthrough in localized therapy, overcoming the potential drawbacks of systemic chemotherapy for tongue carcinoma.
Characterising Functional Venom Profiles of Anthozoans and Medusozoans within Their Ecological Context
Authors: Ashwood Lauren M. , Norton Raymond S. , Undheim Eivind A. B. , Hurwood David A. , Prentis Peter J.
Published: April 2020

This review examines the current state of knowledge regarding toxins from anthozoans (sea anemones, coral, zoanthids, corallimorphs, sea pens and tube anemones). We provide an overview of venom from phylum Cnidaria and review the diversity of venom composition between the two major clades (Medusozoa and Anthozoa). We highlight that the functional and ecological context of venom has implications for the temporal and spatial expression of protein and peptide toxins within class Anthozoa. Understanding the nuances in the regulation of venom arsenals has been made possible by recent advances in analytical technologies that allow characterisation of the spatial distributions of toxins. Furthermore, anthozoans are unique in that ecological roles can be assigned using tissue expression data, thereby circumventing some of the challenges related to pharmacological screening.
Effect of Anisotropic Yield Functions on Prediction of Critical Process Window and Deformation Behavior for Hydrodynamic Deep Drawing of Aluminum Alloys
Authors: Wang Chu , Li Delun , Meng Bao , Wan Min
Published: April 2020

Owing to the reduction of rupture instability and the avoidance of wrinkle defect, the hydrodynamic deep drawing (HDD) process is gradually becoming attractive for fabricating lightweight and complicated products. Meanwhile, since metallic materials present anisotropic deformation behavior, it is necessary to select an appropriate constitutive model for the prediction of plastic deformation behavior of applied material with high precision. In the present research, several anisotropic yield criteria, namely, Hill’48, Yld2000-2d, and BBC2005, were implemented to investigate the effects of yield functions on the prediction accuracy of the critical process window and deformation behavior for the HDD process of 2024 and 5754 aluminum alloys. Material constants in the yield criteria were determined by applying uniaxial and equi-biaxial tension tests and optimizing an error-function using the Levenberg–Marquardt algorithm. Furthermore, the process window diagram was computed utilizing the stress analytical model combined material properties with workpiece geometrical features. Numerical simulation results of predicted material anisotropic parameters, process window, and HDD deformation for aluminum alloys were compared with the experimental data. Through the comparison of diverse yield criteria based on materials’ anisotropic coefficients, critical process window prediction, earing profile, and thickness distribution, it was revealed that the Yld2000-2d and the BBC2005 yield criteria can offer more precise models of material behavior in planar anisotropy properties for the HDD process of 2024 and 5754 aluminum alloys.
Casting and Forming of Advanced Aluminum Alloys
Authors: Puga Hélder
Published: April 2020

The automotive and aeronautical industry´s response to the environmental impact provoked by gas emissions and consumer expectations has driven aluminum alloy casting changes in recent years [...]
Extraction of Titanium from Low-Grade Ore with Different Leaching Agents in Autoclave
Authors: Rodriguez Mario H. , Rosales Gustavo D. , Pinna Eliana G. , Tunez Fernando M. , Toro Norman
Published: April 2020

The progressive depletion of primary sources to obtain metals has led to the search for alternative sources for their recovery. In the particular case of titanium, titaniferous sands are a viable option for obtaining this metal. This paper presents the results of the dissolution of titanium from titaniferous sands of Buenos Aires province (Argentina) in a laboratory autoclave (450 mL of capacity). The operating parameters studied were as follows: different acids (HF, H2SO4 and mixtures of these acids); leaching agent concentration, 5–20% v/v; temperature, 75–150 °C; time, 30–180 min; solid–liquid ratio, 0.9–3.6% w/v; stirring speed, 110–550 rpm. The obtained results indicate that the increase in the leaching agent(s) concentration, temperature and time of contact with the acid mixtures have a marked effect on the dissolution reaction of titanium. Optimal conditions to achieve 89% extraction of titanium were obtained by leaching at 123 °C, 330 rpm, 80 min and 1.8% w/v with a mixture of 15% HF (v/v) and 10% H2SO4 (v/v).
High-Sensitivity in Dielectrophoresis Separations
Authors: Hawkins Benjamin G. , Lai Nelson , Clague David S.
Published: April 2020

The applications of dielectrophoretic (DEP) techniques for the manipulation of cells in a label-free fashion within microfluidic systems continue to grow. However, a limited number of methods exist for making highly sensitive separations that can isolate subtle phenotypic differences within a population of cells. This paper explores efforts to leverage that most compelling aspect of DEP—an actuation force that depends on particle electrical properties—in the background of phenotypic variations in cell size. Several promising approaches, centering around the application of multiple electric fields with spatially mapped magnitude and/or frequencies, are expanding the capability of DEP cell separation.
Fingerprints of Kamafugite-Like Magmas in Mesozoic Lamproites of the Aldan Shield: Evidence from Olivine and Olivine-Hosted Inclusions
Authors: Chayka Ivan F. , Sobolev Alexander V. , Izokh Andrey E. , Batanova Valentina G. , Krasheninnikov Stepan P. , Chervyakovskaya Maria V. , Kontonikas-Charos Alkiviadis , Kutyrev Anton V. , Lobastov Boris M. , Chervyakovskiy Vasiliy S.
Published: April 2020

Mesozoic (125–135 Ma) cratonic low-Ti lamproites from the northern part of the Aldan Shield do not conform to typical classification schemes of ultrapotassic anorogenic rocks. Here we investigate their origins by analyzing olivine and olivine-hosted inclusions from the Ryabinoviy pipe, a well preserved lamproite intrusion within the Aldan Shield. Four types of olivine are identified: (1) zoned phenocrysts, (2) high-Mg, high-Ni homogeneous macrocrysts, (3) high-Ca and low-Ni olivine and (4) mantle xenocrysts. Olivine compositions are comparable to those from the Mediterranean Belt lamproites (Olivine-1 and -2), kamafugites (Olivine-3) and leucitites. Homogenized melt inclusions (MIs) within olivine-1 phenocrysts have lamproitic compositions and are similar to the host rocks, whereas kamafugite-like compositions are obtained for melt inclusions within olivine-3. Estimates of redox conditions indicate that “lamproitic” olivine crystallized from anomalously oxidized magma (∆NNO +3 to +4 log units.). Crystallization of “kamafugitic” olivine occurred under even more oxidized conditions, supported by low V/Sc ratios. We consider high-Ca olivine (3) to be a fingerprint of kamafugite-like magmatism, which also occurred during the Mesozoic and slightly preceded lamproitic magmatism. Our preliminary genetic model suggests that low-temperature, extension-triggered melting of mica- and carbonate-rich veined subcontitental lithospheric mantle (SCLM) generated the kamafugite-like melts. This process exhausted carbonate and affected the silicate assemblage of the veins. Subsequent and more extensive melting of the modified SCLM produced volumetrically larger lamproitic magmas. This newly recognized kamafugitic “fingerprint” further highlights similarities between the Aldan Shield potassic province and the Mediterranean Belt, and provides evidence of an overlap between “orogenic” and “anorogenic” varieties of low-Ti potassic magmatism. Moreover, our study also demonstrates that recycled subduction components are not an essential factor in the petrogenesis of low-Ti lamproites, kamafugites and leucitites.
Significance of Calcite Trace Elements Contents and C-O Isotopic Compositions for Ore-Forming Fluids and Gold Prospecting in the Zhesang Carlin-Like Gold Deposit of Southeastern Yunnan, China
Authors: Wang Jiasheng , Chang Jinyang , Li Chao , Han Zhenchun , Wang Tao , Han Huanhuan
Published: April 2020

The Zhesang gold deposit of southeastern Yunnan is an important component of the Dian-Qian-Gui (Yunnan, Guizhou, and Guangxi) “Golden Triangle”, which hosts a multitude of Carlin-like gold deposits (CLGDs). Calcite is one of the most common gangue minerals in Zhesang. The calcites that have been found in the mining area are classified as ore-stage and post-ore calcites. The ore-stage calcite exhibits a clear paragenetic relationship with gold-bearing arsenopyrite and with an alteration halo that has been cut by the post-ore calcite. To elucidate the origin of the ore-forming fluids of the Zhesang gold deposit and to investigate the possibility of utilizing calcite geochemistry as prospecting indicators, the rare earth elements (REEs), Y, Fe, Mn and Mg contents, and C-O isotopic compositions of calcites from Zhesang have been analyzed. The ore-stage calcite is enriched in middle rare earth elements (MREEs) relative to light rare earth elements (LREEs) and heavy rare earth elements (HREEs) (MREE/LREE = 1.11–1.61, MREE/HREE = 6.12–8.22), whereas post-ore calcite exhibits an enrichment in LREE (LREE/HREE = 4.39–14.93, MREE/LREE = 0.35–0.71). The ore-stage and post-ore calcites were both formed by hydrothermal fluids; however, these hydrothermal fluids may have different sources. The Fe contents of the ore-stage calcite are significantly higher than those of post-ore calcite (4690–6300 μg/g versus 2030–2730 μg/g). Ore-stage calcite also has significantly lower δ18OV-SMOW values than post-ore calcite (11.03–12.49‰ versus 16.48–17.14‰). These calcites with an MREE/LREE ratio greater than 0.92, MREE/HREE ratio greater than 5.69, Fe content greater than 3827 μg/g, and δ18OV-SMOW value less than 14.40‰ represent ore-stage calcites and are important prospecting guidelines. According to the REE, C-O isotopic characteristics of the calcites and the previous findings, it is inferred that the ore-forming fluids of the Zhesang gold deposit were a mixture of crustal fluid by meteoric water leaching wall rocks and a small amount of basic magmatic fluid. The formation of post-ore calcite might be derived from meteoric water and marine carbonates interaction. The ore-forming fluids of the Zhesang gold deposit may be associated with the intrusion of diabase that outcrops in the mining area, and that the basic magmatic activities of the Indosinian period also provided some of the ore-forming materials and heat for gold mineralization.
Transcriptomics in Toxicogenomics, Part III: Data Modelling for Risk Assessment
Authors: Serra Angela , Fratello Michele , Cattelani Luca , Liampa Irene , Melagraki Georgia , Kohonen Pekka , Nymark Penny , Federico Antonio , Kinaret Pia Anneli Sofia , Jagiello Karolina , Ha My Kieu , Choi Jang-Sik , Sanabria Natasha , Gulumian Mary , Puzyn Tomasz , Yoon Tae-Hyun , Sarimveis Haralambos , Grafström Roland , Afantitis Antreas , Greco Dario
Published: April 2020

Transcriptomics data are relevant to address a number of challenges in Toxicogenomics (TGx). After careful planning of exposure conditions and data preprocessing, the TGx data can be used in predictive toxicology, where more advanced modelling techniques are applied. The large volume of molecular profiles produced by omics-based technologies allows the development and application of artificial intelligence (AI) methods in TGx. Indeed, the publicly available omics datasets are constantly increasing together with a plethora of different methods that are made available to facilitate their analysis, interpretation and the generation of accurate and stable predictive models. In this review, we present the state-of-the-art of data modelling applied to transcriptomics data in TGx. We show how the benchmark dose (BMD) analysis can be applied to TGx data. We review read across and adverse outcome pathways (AOP) modelling methodologies. We discuss how network-based approaches can be successfully employed to clarify the mechanism of action (MOA) or specific biomarkers of exposure. We also describe the main AI methodologies applied to TGx data to create predictive classification and regression models and we address current challenges. Finally, we present a short description of deep learning (DL) and data integration methodologies applied in these contexts. Modelling of TGx data represents a valuable tool for more accurate chemical safety assessment. This review is the third part of a three-article series on Transcriptomics in Toxicogenomics.
Influence of Demographic and Lifestyle Variables on Plasma Magnesium Concentrations and Their Associations with Cardiovascular Risk Factors in a Mediterranean Population
Authors: Barragán Rocío , Llopis Juan , Portolés Olga , Sorlí Jose V. , Coltell Oscar , Rivas-García Lorenzo , Asensio Eva M. , Ortega-Azorín Carolina , Corella Dolores , Sánchez-González Cristina
Published: April 2020

Several studies have shown that a low magnesium (Mg) intake in the diet is associated with greater cardiovascular risk and greater risk of diabetes. However, the results are not consistent in all populations. To minimize the biases derived from diet measurement, more objective biomarkers of magnesium status have been proposed. Although there is still no ideal biomarker for Mg, several studies have shown that plasma Mg concentrations could be a relatively acceptable biomarker for cardiovascular risk assessment. However, further studies are required to better characterize this marker in different populations. Our aim was to analyze the association between plasma Mg concentrations (measured through inductively coupled plasma mass spectrometry (ICP-MS)) methods, and cardiovascular risk factors in individuals from a general Mediterranean population (aged 18–80 years). The influence of demographic and lifestyle variables, including adherence to the Mediterranean diet, on plasma Mg concentrations was analyzed. The mean Mg level of the population studied was 0.77 ± 0.08 mmol/L, the prevalence of hypomagnesemia (<0.70 mmol/L) being 18.6%. We did not find any statistically significant differences between plasma Mg concentrations and sex, age, tobacco smoking and total adherence to the Mediterranean diet (p > 0.05). We found a statistically significant association between plasma Mg concentrations and the prevalence of type-2 diabetes (0.77 ± 0.08 mmol/L in non-diabetics versus 0.73 ± 0.13 mmol/L in diabetics; p = 0.009). Despite the low prevalence of type-2 diabetes in this population (11.24% in subjects with hypomagnesemia versus 3.91%, in normomagnesemia; p = 0.005), hypomagnesemia was associated with greater odds of being diabetic in comparison with normomagnesemia (OR = 3.36; p = 0.016, even after adjustment for sex, age, obesity, and medications). On the other hand, no statistically significant association of plasma Mg concentrations with obesity, hypertension, fasting triglycerides, HDL-cholesterol or uric acid was found. However, in contrast to what was initially expected, a statistically significant association was found between plasma Mg concentrations (basically in the highest quartile) and greater total cholesterol (p < 0.05) and LDL-cholesterol concentrations (p < 0.05). In conclusion, our results contribute to increasing the evidence gathered by numerous studies on the inverse association between hypomagnesemia and type-2 diabetes, as well as to the observation, previously reported in some studies, of a direct association with hypercholesterolemia. This paradoxical link should be deeply investigated in further studies.
Adherence to the Mediterranean Diet in Spanish Population and Its Relationship with Early Vascular Aging according to Sex and Age: EVA Study
Authors: Gómez Sánchez Marta , Gómez Sánchez Leticia , Patino-Alonso Maria C , Alonso-Domínguez Rosario , Sánchez-Aguadero Natalia , Lugones-Sánchez Cristina , Rodríguez Sánchez Emiliano , García Ortiz Luis , Gómez-Marcos Manuel A
Published: April 2020

The objective of this study is to analyze the influence of adherence to the Mediterranean diet (MDA) and its components on early vascular aging (EVA) in a Spanish population sample free of cardiovascular disease and to analyze the differences by sex. Methods: We recruited 501 individuals aged 35–75 without cardiovascular disease by random sampling (55.90 ± 14.24 years, 49.70% men). EVA was defined in two steps: Step 1: subjects with vascular damage in carotid arteries or peripheral artery disease were classified as EVA. Step 2: subjects at the percentile of the combined Vascular Aging Index (VAI) were classified; ≥ p90 was considered EVA and < p90 was considered normal vascular aging (NVA), estimated using the following formula (VAI = (log (1.09) × 10 cIMT + log (1.14) cfPWV) × 39.1 + 4.76 by age and sex. Carotid-femoral pulse wave velocity (cfPWV) was measured by SphigmoCor System® and carotid intima-media thickness by Sonosite Micromax® ultrasound and classified thus: values ≥ Percentile 90 were considered EVA and those < Percentile 90 as NVA, with population percentiles analyzed. The principal result variable was assessed using the 14-item MEDAS questionnaire, developed and validated by the PREDIMED group, comprising 12 questions about the frequency of food consumption and two questions regarding the Spanish population’s typical eating habits. Results: MDA was observed by 25% (17% men and 34% women). EVA was present in 17% (29% men and 4% women). The adjusted logistic regression models showed that an increase in MDA decreases the probability of EVA in the global analysis (OR = 0.36; 95% CI: 0.16–0.82). In the analysis by sex, this association was only seen in men (OR = 0.33; 95% CI: 0.12–0.86), but not in women (OR = 0.31; 95% CI: 0.04–2.50). Conclusion: The results of this study suggest that a greater adherence to the Mediterranean diet decreases the probability of presenting EVA. In the analysis by sex, this association applies only to men.
Definitions, Sources and Self-Reported Consumption of Regionally Grown Fruits and Vegetables in Two Regions of Australia
Authors: Kent Katherine , Godrich Stephanie , Murray Sandra , Auckland Stuart , Blekkenhorst Lauren , Penrose Beth , Lo Johnny , Devine Amanda
Published: April 2020

Regional food systems are complex networks, with numerous retail sources that underpin a local economy. However, evidence is limited regarding how consumers define, identify, and source regionally grown fresh fruits and vegetables (RGFFV). A cross-sectional study was conducted in Tasmania (TAS) and South Western Australia (SWA) to compare how RGFFV are defined, identified and sourced by consumers, including self-reported consumption of selected RGFFV. Survey data were analyzed using the Chi-square test and t-tests. Results (TAS n = 120, SWA n = 123) identified that consumers had mixed perceptions of how RGFFV are defined, including produce sold at farmers markets, or grown within their region (TAS/SWA). RGFFV were commonly identified using product labelling (55% TAS, 69% SWA; p > 0.05). Respondents reported frequently shopping for RGFFV at major supermarkets, with more TAS respondents shopping weekly in comparison to SWA respondents (67% vs. 38%; p < 0.001). Supermarkets offered convenience and consumers enjoyed the experience of farmers’ markets, especially in TAS (42%) in comparison to SWA (21%; p = 0.012). The major RGFFV consumed were root vegetables and apples/pears, but consumers were frequently unsure about the produce’s provenance. Our findings indicate multiple opportunities to improve consumption of fresh, regional produce in TAS and SWA, which may positively impact regional economic growth and community health.
Dietary Supplementation with Curcumin Reduce Circulating Levels of Glycogen Synthase Kinase-3β and Islet Amyloid Polypeptide in Adults with High Risk of Type 2 Diabetes and Alzheimer’s Disease
Authors: Thota Rohith N , Rosato Jessica I , Dias Cintia B , Burrows Tracy L , Martins Ralph N , Garg Manohar L
Published: April 2020

Dietary supplementation with curcumin has been previously reported to have beneficial effects in people with insulin resistance, type 2 diabetes (T2D) and Alzheimer’s disease (AD). This study investigated the effects of dietary supplementation with curcumin on key peptides implicated in insulin resistance in individuals with high risk of developing T2D. Plasma samples from participants recruited for a randomised controlled trial with curcumin (180 mg/day) for 12 weeks were analysed for circulating glycogen synthase kinase-3 β (GSK-3β) and islet amyloid polypeptide (IAPP). Outcome measures were determined using ELISA kits. The homeostasis model for assessment of insulin resistance (HOMA-IR) was measured as parameters of glycaemic control. Curcumin supplementation significantly reduced circulating GSK-3β (−2.4 ± 0.4 ng/mL vs. −0.3 ± 0.6, p = 0.0068) and IAPP (−2.0 ± 0.7 ng/mL vs. 0.4 ± 0.6, p = 0.0163) levels compared with the placebo group. Curcumin supplementation significantly reduced insulin resistance (−0.3 ± 0.1 vs. 0.01 ± 0.05, p = 0.0142) compared with placebo group. Dietary supplementation with curcumin reduced circulating levels of IAPP and GSK-3β, thus suggesting a novel mechanism through which curcumin could potentially be used for alleviating insulin resistance related markers for reducing the risk of T2D and AD.
Effects of Motor Mental Imagery Training on Tennis Service Performance during the Ramadan Fasting: A Randomized, Controlled Trial
Authors: Fekih Sofien , Zguira Mohamed Sami , Koubaa Abdessalem , Masmoudi Liwa , Bragazzi Nicola Luigi , Jarraya Mohamed
Published: April 2020

The objective of the present study is to analyze the effects of motor mental imagery training on tennis service performance among tennis athletes who fast during Ramadan. Participants were 38 young male tennis players, randomly divided into two groups: Imaging Training (IMG, n = 18) and control group (CG, n = 20). The CG has watched videos on the history of the Olympic Games, while IMG has followed a training program in motor imagery. The performance of the tennis service was obtained by the product between accuracy and speed of typing (accuracy × average speed of all shots (km/h)). The effect of group/time interaction (p < 0.01) was identified for all performance indicators (accuracy, running speed and performance (speed × precision)), with improvement only in IMG (p = 0.01). The results showed that motor imagery training could be an effective strategy for mitigating/counteracting the negative effects of Ramadan on the tennis service performance.
Mechanisms of Action of Prebiotics and Their Effects on Gastro-Intestinal Disorders in Adults
Authors: Guarino Michele , Altomare Annamaria , Emerenziani Sara , Di Rosa Claudia , Ribolsi Mentore , Balestrieri Paola , Iovino Paola , Rocchi Giulia , Cicala Michele
Published: April 2020

In recent years, research has focused on the use of dietary fibers and prebiotics, since many of these polysaccharides can be metabolized by intestinal microbiota, leading to the production of short-chain fatty acids. The metabolites of prebiotic fermentation also show anti-inflammatory and immunomodulatory capabilities, suggesting an interesting role in the treatment of several pathological conditions. Galacto-oligosaccharide and short- and long-chain fructans (Fructo-oligosaccharides and inulin) are the most studied prebiotics, even if other dietary compounds seem to show the same features. There is an increasing interest in dietary strategies to modulate microbiota. The aim of this review is to explore the mechanisms of action of prebiotics and their effects on the principal gastro-intestinal disorders in adults, with a special focus on Galacto-oligosaccharides, Fructo-oligosaccharides, lactulose and new emerging substances which currently have evidence of prebiotics effects, such as xilooligosaccharides, soybean oligosaccharides, isomaltooligosaccharides, lactobionic acid, resistant starch and polyphenols.