bluuebunny/crossref_metadata_2025 huggingface dataset:
Mini-Review on the Possible Interconnections between the Gut-Brain Axis and the Infertility-Related Neuropsychiatric Comorbidities
Authors: Simionescu Gabriela , Ilie Ovidiu-Dumitru , Ciobica Alin , Doroftei Bogdan , Maftei Radu , Grab Delia , McKenna Jack , Dhunna Nitasha , Mavroudis Ioannis , Anton Emil
Published: June 2020

Both the gut-brain axis (GBA) and the hypothalamic–pituitary–adrenal (HPA) axis remain an intriguing yet obscure network with a strong influence over other systems of organs. Recent reports have sought to describe the multitude of harmful stressors that may impact the HPA axis along with the interconnections between these. This has improved our knowledge of how the underlying mechanisms working to establish homeostasis are affected. A disruption to the HPA axis can amplify the chances of gastrointestinal deficiencies, whilst also increasing the risk of a wide spectrum of neuropsychiatric disorders. Thus, the influence of microorganisms found throughout the digestive tract possess the ability to affect both physiology and behaviour by triggering responses, which may be unfavourable. This is sometimes the case in of infertility. Numerous supplements have been formulated with the intention of rebalancing the gut microflora. Accordingly, the gut flora may alter the pharmacokinetics of drugs used as part of fertility treatments, potentially exacerbating the predisposition for various neurological disorders, regardless of the age and gender.
Stable Continuous Production of γ-Valerolactone from Biomass-Derived Levulinic Acid over Zr–Al-Beta Zeolite Catalyst
Authors: López-Aguado Clara , Paniagua Marta , Melero Juan A. , Iglesias Jose , Juárez Pablo , López Granados Manuel , Morales Gabriel
Published: June 2020

The one-pot conversion of biomass-derived platform molecules such as levulinic acid (LA) and furfural (FAL) into γ-valerolactone (GVL) is challenging because of the need for adequate multi-functional catalysts and high-pressure gaseous hydrogen. As a more sustainable alternative, here we describe the transfer hydrogenation of LA to GVL using isopropanol as a hydrogen donor over a Zr-modified beta zeolite catalyst in a continuous fixed-bed reactor. A stable sustained production of GVL was achieved from the levulinic acid, with both high LA conversion (ca. 95%) and GVL yield (ca. 90%), for over at least 20 days in continuous operation at 170 °C. Importantly, the small decay in activity can be advantageously overcome by the means of a simple in situ thermal regeneration in the air atmosphere, leading to a complete recovery of the catalyst activity. Key to this outstanding result is the use of a Zr-modified dealuminated beta zeolite with a tailored Lewis/Brønsted acid sites ratio, which can synergistically catalyze the tandem steps of hydrogen transfer and acid-catalyzed transformations, leading to such a successful and stable production of GVL from LA.
Selective Recovery of Manganese from Anode Sludge Residue by Reductive Leaching
Authors: Kauppinen Toni , Vielma Tuomas , Salminen Justin , Lassi Ulla
Published: June 2020

Manganese-containing anode sludge is a common side-product in the electrowinning of zinc. The anode sludge consists mainly of oxidized manganese, but also lesser amounts of lead, calcium, and other minor metals. The impurities present in the anode sludge mandate new recycling strategies for its efficient use. This work demonstrates a novel method for selective manganese recovery from lead- and calcium-bearing manganese oxide solid residue. Leaching with sulfuric acid in the presence of a selected reducing agent, such as hydrogen peroxide or citric acid, yields a concentrated MnSO4 solution with high selectivity over calcium and lead. Manganese yields up to 98% can be obtained. Minimization of calcium and lead in final manganese product can be accomplished with the correct choice of leaching conditions. Alongside manganese sulfate solution, leaching residue with high content of lead and silver was also formed.
Structure and Phase Transition Features of Monoclinic and Tetragonal Phases in U–Mo Alloys
Authors: Kolotova Lada , Gordeev Ilia
Published: June 2020

Using molecular dynamics simulations, we studied the structural properties of orthorhombic, monoclinic, and body-centered tetragonal (bct) phases of U–Mo alloys. A sequence of shear transformations between metastable phases takes place upon doping of uranium with molybdenum from pure α -U: orthorhombic α ′ → monoclinic α ″ → bct γ 0 → body-centered cubic (bcc) with doubled lattice constant γ s → bcc γ . The effects of alloy content on the structure of these phases have been investigated. It has been shown that increase in molybdenum concentration leads to an increase in the monoclinic angle and is more similar to the γ 0 -phase. In turn, tetragonal distortion of the γ 0 -phase lattice with displacement of a central atom in the basic cell along the <001> direction makes it more like the α ″ -phase. Both of these effects reduce the necessary shift in atomic positions for the α ″ → γ 0 -phase transition.
Influence of the Rake Angle on Nanocutting of Fe Single Crystals: A Molecular-Dynamics Study
Authors: Alhafez Iyad Alabd , Urbassek Herbert M.
Published: June 2020

Using molecular dynamics simulation, we study the cutting of an Fe single crystal using tools with various rake angles α . We focus on the (110)[001] cut system, since here, the crystal plasticity is governed by a simple mechanism for not too strongly negative rake angles. In this case, the evolution of the chip is driven by the generation of edge dislocations with the Burgers vector b = 1 2 [ 111 ] , such that a fixed shear angle of ϕ = 54.7 ∘ is established. It is independent of the rake angle of the tool. The chip form is rectangular, and the chip thickness agrees with the theoretical result calculated for this shear angle from the law of mass conservation. We find that the force angle χ between the direction of the force and the cutting direction is independent of the rake angle; however, it does not obey the predictions of macroscopic cutting theories, nor the correlations observed in experiments of (polycrystalline) cutting of mild steel. Only for (strongly) negative rake angles, the mechanism of plasticity changes, leading to a complex chip shape or even suppressing the formation of a chip. In these cases, the force angle strongly increases while the friction angle tends to zero.
Effects of Depth of Cutting on Damage Interferences during Double Scratching on Single Crystal SiC
Authors: Nian Duan
Published: June 2020

In this work, the damage interference during scratching of single crystal silicon carbide (SiC) by two cone-shaped diamond grits was experimentally investigated and numerically analyzed by coupling the finite element method (FEM) and smoothed particle hydrodynamics (SPH), to reveal the interference mechanisms during the micron-scale removal of SiC at variable Z-axis spacing along the depth of cutting (DOC) direction. The simulation results were well verified by the scratching experiments. The damage interference mechanism of SiC during double scratching at micron-scale was found to be closely related to the material removal modes, and can be basically divided into three stages at different DOCs: combined interference of plastic and brittle removal in the case of less than 5 µm, interference of cracks propagation when DOC was increased to 5 µm, and weakened interference stage during the fracture of SiC in the case of greater than 5 µm. Hence, DOC was found to play a determinant role in the damage interference of scratched SiC by influencing the material removal mode. When SiC was removed in a combined brittle-plastic mode, the damage interference occurred mainly along the DOC direction; when SiC was removed in a brittle manner, the interference was mainly along the width of cutting; and more importantly, once the fragment of SiC was initiated, the interference was weakened and the effect on the actual material removal depth also reduces. Results obtained in this work are believed to have essential implications for the optimization of SiC wafer planarization process that is becoming increasingly important for the fabrication of modern electronic devices.
Investigation of the Blistering and Exfoliation Mechanism of GaAs Wafers and SiO2/Si3N4/GaAs Wafers by He+ and H+ Implantation
Authors: Huang Rui , Lan Tian , Li Chong , Li Jing , Wang Zhiyong
Published: June 2020

The thermally activated blistering and exfoliation of GaAs wafers and SiO2/Si3N4/GaAs wafers after H+ and He+ implantation is systematically investigated. Surface morphologies and microscopic defects are detected and analyzed by various measurements, such as optical microscopy (OM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Blistering and exfoliation are obtained on the surfaces of the GaAs and SiO2/Si3N4/GaAs wafers by either the exclusive implantation of 5 × 1016 He+/cm2 alone or by co-implantation of 0.5 × 1016 He+/cm2 and 4 × 1016 H+/cm2. Our experimental results show that the blistering and exfoliation of the SiO2/Si3N4/GaAs layer occurred when the concentration of He+ was relatively low, where fewer dislocations and nanocavities were created near the interface between the Si3N4 and GaAs layers.
The Application of Structural Retinal Biomarkers to Evaluate the Effect of Intravitreal Ranibizumab and Dexamethasone Intravitreal Implant on Treatment of Diabetic Macular Edema
Authors: Ceravolo Ida , Oliverio Giovanni William , Alibrandi Angela , Bhatti Ahsan , Trombetta Luigi , Rejdak Robert , Toro Mario Damiano , Trombetta Costantino John
Published: June 2020

Background: The aim of this study was to compare the therapeutic effect of intravitreal treatment with ranibizumab and dexamethasone using specific swept-source optical coherence tomography retinal biomarkers in patients with diabetic macular edema (DME). Methods: 156 treatment-naïve patients with DME were divided in two groups: 75 patients received 3 monthly intravitreal injections of ranibizumab 0.5 mg (Lucentis®) (Group 1) and 81 patients received an intravitreal implant of dexamethasone 0.7 mg (Ozurdex®) (Group 2). Patients were evaluated at baseline (V1), at three months post-treatment in Group 1, and at two months post-treatment in Group 2 (V2). Best-corrected visual acuity (BCVA) and swept source-OCT were recorded at each interval. Changes between V1 and V2 were analyzed using the Wilcoxon test and differences between the two groups of treatment were assessed using the Mann–Whitney test. Multiple regression analysis was performed to evaluate the possible OCT biomarker (CRT, ICR, CT, SND, HRS) as predictive factors for final visual acuity improvement. Results: In both groups, BCVA improved (p-value < 0.0001), and a significant reduction in central retinal thickness, intra-retinal cysts, red dots, hyper-reflective spots (HRS), and serous detachment of neuro-epithelium (SDN) was observed. A superiority of dexamethasone over ranibizumab in reducing the SDN height (p-value = 0.03) and HRS (p-value = 0.01) was documented. Conclusions: Ranibizumab and dexamethasone are effective in the treatment of DME, as demonstrated by functional improvement and morphological biomarker change. DME associated with SDN and HRS represents a specific inflammatory pattern for which dexamethasone appears to be more effective.
Analysis of Yoga as an Inclusive Sport in Educational Contexts
Authors: Moreno Molina David , Hernández Fernández Antonio , Pérez Navío Eufrasio
Published: June 2020

Yoga is a growing sport in our current society, but we know little about it; what repercussions it has, what benefits its practice brings, repercussions in the educational environment, etc. Therefore, the objective of the article was to analyze if it is possible to design a scale of perception that relates yoga, teacher training, sport, benefits of yoga, and inclusive sport. The objective was to analyze and demonstrate the relationship between variables determining how the academic performance of the students can be improved, since the practice of yoga influences on diverse areas that cause changes at brain level in the students, and it can lead to better attentiveness, memory, etc. For this, a descriptive, explanatory, and correlational research project has been carried out with a quantitative methodology. The analysis sample was made up of 1575 subjects, distributed as follows: 1191 students of the Degree in Primary Education of the University of Jaén (from first to fourth course) and 384 teachers corresponding to different public centers of the province of Jaén. In order to investigate the objective, an operational table was created to construct the Likert scale. The original scale consisted of 20 items reporting an alpha of 0.826, we achieved a reduction of four items, with a higher reliability (0.846), divided into five different dimensions. Likewise, construct validity was checked from a factorial analysis (KM0 = 0.787, Bartlett 0.000). The results of the research have been satisfactory, given that when analyzing the variables proposed in the initial objective, a high degree of correlation has been obtained between them, which supposes, applying it to the educational scope, a great incentive to carry it out in the educational centers, and, therefore, to improve the academic, personal, and social performance of the student.
Priority-Based Bandwidth Management in Virtualized Software-Defined Networks
Authors: Leonardi Luca , Lo Bello Lucia , Aglianò Simone
Published: June 2020

In Industrial Internet of Things (IoT) applications, when the network size increases and different types of flows share the bandwidth, the demand for flexible and efficient management of the communication network is compelling. In these scenarios, under varying workload and flow priorities, the combined use of Software-Defined Networking (SDN) and Network Virtualization (NV) is a promising solution, as such techniques allow to reduce the network management complexity. This work presents the PrioSDN Resource Manager (PrioSDN_RM), a resource management mechanism based on admission control for virtualized SDN-based networks. The proposed combination imposes bounds on the resource utilization for the virtual slices, which therefore share the network links, while maintaining isolation from each other. The presented approach exploits a priority-based runtime bandwidth distribution mechanism to dynamically react to load changes (e.g., due to alarms). The paper describes the design of the approach and provides experimental results obtained on a real testbed.
Energy Efficient Computation Offloading Mechanism in Multi-Server Mobile Edge Computing—An Integer Linear Optimization Approach
Authors: Khan Prince Waqas , Abbas Khizar , Shaiba Hadil , Muthanna Ammar , Abuarqoub Abdelrahman , Khayyat Mashael
Published: June 2020

Conserving energy resources and enhancing computation capability have been the key design challenges in the era of the Internet of Things (IoT). The recent development of energy harvesting (EH) and Mobile Edge Computing (MEC) technologies have been recognized as promising techniques for tackling such challenges. Computation offloading enables executing the heavy computation workloads at the powerful MEC servers. Hence, the quality of computation experience, for example, the execution latency, could be significantly improved. In a situation where mobile devices can move arbitrarily and having multi servers for offloading, computation offloading strategies are facing new challenges. The competition of resource allocation and server selection becomes high in such environments. In this paper, an optimized computation offloading algorithm that is based on integer linear optimization is proposed. The algorithm allows choosing the execution mode among local execution, offloading execution, and task dropping for each mobile device. The proposed system is based on an improved computing strategy that is also energy efficient. Mobile devices, including energy harvesting (EH) devices, are considered for simulation purposes. Simulation results illustrate that the energy level starts from 0.979 % and gradually decreases to 0.87 % . Therefore, the proposed algorithm can trade-off the energy of computational offloading tasks efficiently.
The Use of Wood Chips for Revitalization of Degraded Forest Soil on Young Scots Pine Plantation
Authors: Klimek Andrzej , Rolbiecki Stanisław , Rolbiecki Roman , Gackowski Grzegorz , Stachowski Piotr , Jagosz Barbara
Published: June 2020

The aim of the study was to assess the impact of several methods of mulching degraded forest soil with wood chips on the development of mite (Acari) community, with particular emphasis to oribatid mites (Oribatida), and on the growth of young plantings of Scots pine (Pinus sylvestris L.). Mulching with wood chips should contribute to revitalize soil fauna and restore natural forests on degraded soils. Scots pine seedlings were planted at the post-military training ground. Four experimental treatments were tested: control—uncovered soil (C), mulching with wood chips (W), W + mycorrhiza preparation (WM), and W + forest litter (WL). At the end of the growing season in 2012, 2013 and 2014, the following plant measurements were carried out: length of annual increment of the main stem, stem base diameter, number and lengths of lateral shoots in the annual whorl. The mite calculations included average mite density, dominance index, species richness, oribatid mite diversity, average number of species, and Shannon general species diversity index. The use of mulching with wood chips did not significantly affect the growth characteristics of Scots pine plants, but strongly increased the mite community. After mulching, the total number and species diversity of Acari increased many times, and Oribatida began to dominate among micro-arthropods. The number of Oribatida increased most in W. The largest species diversity was observed in WL. 24 species of Oribatida were found that were used as the bio-indicators of soil succession changes. Tectocepheus velatus clearly dominated in all mulching treatments. Oppiella nova and Scutovertex sculptus were also numerous populations of Oribatida. The study shows that mulching with Scots pine wood chips, especially with the addition of forest litter, significantly enriches soil fauna and is therefore useful in the regeneration process of degenerated forest soils.
Predicting the Potential Global Geographical Distribution of Two Icerya Species under Climate Change
Authors: Liu Yang , Shi Juan
Published: June 2020

Climate change is predicted to alter the geographic distribution of a wide variety of taxa, including insects. Icerya aegyptiaca (Douglas) and I. purchasi Maskell are two polyphagous and invasive pests in the genus Icerya Signoret (Hemiptera: Monophlebidae) and cause serious damage to many landscape and economic trees. However, the global habitats suitable for these two Icerya species are unclear. The purpose of this study is to determine the potentially suitable habitats of these two species, then to provide scientific management strategies. Using MaxEnt software, the potential risk maps of I. aegyptiaca and I. purchasi were created based on their occurrence data under different climatic conditions and topology factors. The results suggested that under current climate conditions, the potentially habitable area of I. aegyptiaca would be much larger than the current distribution and there would be small changes for I. purchasi. In the future climate change scenarios, the suitable habitats of these two insect species will display an increasing trend. Africa, South America and Asia would be more suitable for I. aegyptiaca. South America, Asia and Europe would be more suitable for I. purchasi. Moreover, most of the highly habitat suitability areas of I. aegyptiaca will become concentrated in Southern Asia. The results also suggested that “min temperature of coldest month” was the most important environmental factor affecting the prediction models of these two insects. This research provides a theoretical reference framework for developing policies to manage and control these two invasive pests of the genus Icerya.
On the Fractional Maximal Delta Integral Type Inequalities on Time Scales
Authors: Akın Lütfi
Published: June 2020

Time scales have been the target of work of many mathematicians for more than a quarter century. Some of these studies are of inequalities and dynamic integrals. Inequalities and fractional maximal integrals have an important place in these studies. For example, inequalities and integrals contributed to the solution of many problems in various branches of science. In this paper, we will use fractional maximal integrals to establish integral inequalities on time scales. Moreover, our findings show that inequality is valid for discrete and continuous conditions.
Geointelligence against Illegal Deforestation and Timber Laundering in the Brazilian Amazon
Authors: Perazzoni Franco , Bacelar-Nicolau Paula , Painho Marco
Published: June 2020

Due to the characteristics of the Southern Amazonas Mesoregion (Mesorregião Sul do Amazonas, MSA), conducting on-site surveys in all licensed forestry areas (Plano de Manejo Florestal, PMFS) is an impossible task. Therefore, the present investigation aimed to: (i) analyze the use of geointelligence (GEOINT) techniques to support the evaluation of PMFS; and (ii) verify if the PMFS located in the MSA are being executed in accordance with Brazilian legislation. A set of twenty-two evaluation criteria were established. These were initially applied to a “standard” PMFS and subsequently replicated to a larger area of 83 PMFS, located in the MSA. GEOINT allowed for a better understanding of each PMFS, identifying illegal forestry activities and evidence of timber laundering. Among these results, we highlight the following evidences: (i) inconsistencies related to total transport time and prices declared to the authorities (70% of PMFS); (ii) volumetric information incompatible with official forest inventories and/or not conforming with Benford’s law (54% of PMFS); (iii) signs of exploitation outside the authorized polygon limits (51% of PMFS) and signs of clear-cutting (43% of PMFS); (iv) no signs of infrastructure compatible with licensed forestry (24% of PMFS); and (v) signs of exploitation prior to the licensing (19% of PMFS) and after the expiration of licensing (5%).
Developing an Equivalent Solid Material Model for BCC Lattice Cell Structures Involving Vertical and Horizontal Struts
Authors: Alwattar Tahseen A. , Mian Ahsan
Published: June 2020

In this study, a body-centered cubic (BCC) lattice unit cell occupied inside a frame structure to create a so-called “InsideBCC” is considered. The equivalent quasi-isotropic properties required to describe the material behavior of the InsideBCC unit cell are equivalent Young’s modulus ( E e ) , equivalent shear modulus ( G e ) , and equivalent Poisson’s ratio ( ν e ) . The finite element analysis (FEA) based computational approach is used to simulate and calculate the mechanical responses of InsideBCC unit cell, which are the mechanical responses of the equivalent solid. Two separates finite element models are then developed for samples under compression: one with a 6 × 6 × 4 cell InsideBCC lattice cell structure (LCS) and one completely solid with equivalent solid properties obtained from a unit cell model. In addition, 6 × 6 × 4 cell specimens are fabricated on a fused deposition modeling (FDM) uPrint SEplus 3D printer using acrylonitrile butadiene styrene (ABS) material and tested experimentally under quasi-static compression load. Then, the results extracted from the finite element simulation of both the entire lattice and the equivalent solid models are compared with the experimental data. A good agreement between the experimental stress–strain behavior and that obtained from the FEA models is observed within the linear elastic limit.
“Monoclonal-Type” Plastic Antibodies for COVID-19 Treatment: What Is the Idea?
Authors: Puoci Francesco
Published: June 2020

In late December 2019, an outbreak due to a novel coronavirus, initially called 2019-nCoV, was reported in Wuhan, China [...]
Study on the Quantitative Evaluation of the Surface Force Using a Scanning Probe Microscope
Authors: Yagi Wataru , Honda Tomomi , Tamura Kazushi , Narita Keiichi
Published: June 2020

There are two types of friction modifiers (FMs) used as lubricant additives: Reaction film FMs (RF-FMs) and adsorption film FMs (AF-FMs). While RF-FMs provide good performance in severe conditions, AF-FMs excel in mild conditions. This empirical evidence leads us to combine these two FMs to cover broader conditions. However, the effects of their combination are highly complicated due to the interaction between these FMs. If the interaction force of AF-FMs with various materials can be evaluated, it would help us to improve tribological performances of lubricants. Although atomic force microscopy seems suitable for this application, we found some obstacles, such as fluid resistance, electrostatic force, and laser positioning of the cantilever, to achieve proper measurements of the adsorption force. In this study, the adsorption force between the polar group and the surface was directly measured in oil with a 1 µm silica probe modified with CH3 or COOH. This paper proposed how to eliminate errors included in the adsorption force measurement using AFM and a calibration method for obtaining an accurate adsorption force of the polar group, and a test of normality of the measured data was conducted by 400 measurements. As a result, it was shown that approximately 100 tests were needed to obtain an accurate adsorption force in this study.
The Development of Electroconvection at the Surface of a Heterogeneous Cation-Exchange Membrane Modified with Perfluorosulfonic Acid Polymer Film Containing Titanium Oxide
Authors: Gil Violetta , Porozhnyy Mikhail , Rybalkina Olesya , Butylskii Dmitrii , Pismenskaya Natalia
Published: June 2020

One way to enhance mass transfer and reduce fouling in wastewater electrodialysis is stimulation of electroconvective mixing of the solution adjoining membranes by modifying their surfaces. Several samples were prepared by casting the perfluorosulfonic acid (PFSA) polymer film doped with TiO2 nanoparticles onto the surface of the heterogeneous cation-exchange membrane MK-40. It is found that changes in surface characteristics conditioned by such modification lead to an increase in the limiting current density due to the stimulation of electroconvection, which develops according to the mechanism of electroosmosis of the first kind. The greatest increase in the current compared to the pristine membrane can be obtained by modification with the film being 20 μm thick and containing 3 wt% of TiO2. The sample containing 6 wt% of TiO2 provides higher mass transfer in overlimiting current modes due to the development of nonequilibrium electroconvection. A 1.5-fold increase in the thickness of the modifying film reduces the positive effect of introducing TiO2 nanoparticles due to (1) partial shielding of the nanoparticles on the surface of the modified membrane; (2) a decrease in the tangential component of the electric force, which affects the development of electroconvection.
A Newly Discovered Relation between the Critical Resolved Shear Stress and the Fatigue Endurance Limit for Metallic Materials
Authors: Mlikota Marijo , Schmauder Siegfried
Published: June 2020

The paper introduces a valuable new description of fatigue strength in relation to material properties and thus a new perspective on the overall understanding of the fatigue process. Namely, a relation between the endurance limits and the accompanying values of the critical resolved shear stress (CRSS) for various metallic materials has been discovered by means of a multiscale approach for fatigue simulation. Based on the uniqueness of the relation, there is a strong indication that it is feasible to relate the endurance limit to the CRSS and not to the ultimate strength, as often done in the past.
High Temperature Cyclic Plastic Response of New-Generation ODS Alloy
Authors: Chlupová Alice , Šulák Ivo , Svoboda Jiří
Published: June 2020

The very recently developed coarse-grained new-generation oxide dispersion strengthened (ODS) alloys containing 5 vol.% homogeneously distributed yttrium nano-precipitates seems to be a promising oxidation-resistant structural material for applications at temperatures above 1000 °C. The primary aim of the present paper is the introduction of the new-generation oxide dispersion strengthened (ODS) alloy and the first testing of its high temperature fatigue properties at 800 °C, concurrently demonstrating a novel and very efficient methodology by using an incremental fatigue step test. The successful application of the methodology motivates the authors to test the fatigue properties of new generation ODS alloys at 1000–1200 °C in the near future.
Optimization of Niobium Content in Direct Quenched High-Strength Steels
Authors: Hannula Jaakko , Porter David , Kaijalainen Antti , Somani Mahesh , Kömi Jukka
Published: June 2020

This paper focuses on understanding the effect of niobium content on the phase transformation behavior and resultant mechanical properties of thermomechanically rolled and direct-quenched low carbon steels containing 0.08 wt.% carbon. Investigated steels contained three different levels of niobium: 0, 0.02 and 0.05 wt.%. The continuous cooling transformation (CCT) diagrams covering cooling rates in the range 3–96 °C/s constructed based on the dilatometer studies showed only a minor effects of Nb on the phase transformation characteristics. In addition, experiments were performed for reheating and soaking the slabs at 1050–1200 °C and the results revealed that for these low-carbon steels, Nb failed to prevent the austenite grain growth during slab reheating. In the case of hot rolling trials, two different finish rolling temperatures of 820 °C and 920 °C were used to obtain different levels of pancaking in the austenite prior to direct quenching. The resultant microstructures were essentially mixtures of autotempered martensite and lower bainite imparting yield strengths in the range 940–1070 MPa. The lower finish rolling temperature enabled better combinations of strength and toughness in all the cases, predominantly due to a higher degree of pancaking in the austenite. The optimum level of Nb in the steel was ascertained to be 0.02 wt.%, which resulted not only in marginally higher strength but also without any significant loss of impact toughness.
Heat Treatment Effect on Microstructure Evolution in a 7% Cr Steel for Forging
Authors: Di Schino Andrea , Gaggiotti Matteo , Testani Claudio
Published: June 2020

Well-defined heat-treatment guidelines are required to achieve the target mechanical properties in high-chromium steels for forgings. Moreover, for this class of materials, the microstructure evolution during heat treatment is not clearly understood. Thus, it is particularly important to assess the steel microstructure evolution during heat treatment, in order to promote the best microstructure. This will ascertain the safe use for long-term service. In this paper, different heat treatments are considered, and their effect on a 7% Cr steel for forging is reported. Results show that, following the high intrinsic steel hardenability, significative differences were not found versus the cooling-step treatment, although prior austenite grain size was significantly different. Moreover, retained austenite (RA) content is lower in double-tempered specimens after heat treatments at higher temperatures.
Synthesis and Surface Engineering of Inorganic Nanomaterials Based on Microfluidic Technology
Authors: Shen Jie , Shafiq Muhammad , Ma Ming , Chen Hangrong
Published: June 2020

The controlled synthesis and surface engineering of inorganic nanomaterials hold great promise for the design of functional nanoparticles for a variety of applications, such as drug delivery, bioimaging, biosensing, and catalysis. However, owing to the inadequate and unstable mass/heat transfer, conventional bulk synthesis methods often result in the poor uniformity of nanoparticles, in terms of microstructure, morphology, and physicochemical properties. Microfluidic technologies with advantageous features, such as precise fluid control and rapid microscale mixing, have gathered the widespread attention of the research community for the fabrication and engineering of nanomaterials, which effectively overcome the aforementioned shortcomings of conventional bench methods. This review summarizes the latest research progress in the microfluidic fabrication of different types of inorganic nanomaterials, including silica, metal, metal oxides, metal organic frameworks, and quantum dots. In addition, the surface modification strategies of nonporous and porous inorganic nanoparticles based on microfluidic method are also introduced. We also provide the readers with an insight on the red blocks and prospects of microfluidic approaches, for designing the next generation of inorganic nanomaterials.
Hierarchical Doped Gelatin-Derived Carbon Aerogels: Three Levels of Porosity for Advanced Supercapacitors
Authors: Kandasamy Ayshuwarya , Ramasamy Tamilselvi , Samrin Ayesha , Narayanasamy Padmanathan , Mohan Ramesh , Bazaka Olha , Levchenko Igor , Bazaka Kateryna , Mohandas Mandhakini
Published: June 2020

Nitrogen-doped graphene-based aerogels with three levels of hierarchically organized pores were prepared via a simple environmentally friendly process, and successfully tested in supercapacitor applications. Mesopores and macropores were formed during the aerogel preparation followed by carbonization and its chemical activation by potassium hydroxide (KOH). These mesopores and macropores consist of amorphous carbon and a 3D graphene framework. Thermal treatment at 700 °C, 800 °C, 900 °C in N2 atmosphere was done to etch out the amorphous carbon and obtain a stable N-doped 3D graphene. Specific capacitance values obtained from the electrochemical measurements are in the range of 232–170 F× g−1. The thus fabricated structures showed excellent cyclic stability, suggesting that these materials have potential as electrodes for solid asymmetric supercapacitors.
Customized In Situ Functionalization of Nanodiamonds with Nanoparticles for Composite Carbon-Paste Electrodes
Authors: Montes Raquel , Sánchez Gerard , Zhao Jingjing , Palet Cristina , Baeza Mireia , Bastos-Arrieta Julio
Published: June 2020

The incorporation of nanomaterials on (bio)sensors based on composite materials has led to important advances in the analytical chemistry field due to the extraordinary properties that these materials offer. Nanodiamonds (NDs) are a novel type of material that has raised much attention, as they have the possibility of being produced on a large scale by relatively inexpensive synthetic methodologies. Moreover, NDs can present some other interesting features, such as fluorescence, due to surface functionalization and proved biocompatibility, which makes them suitable for biomedical applications. In addition, NDs can be customized with metallic nanoparticles (NPs), such as silver or gold, in order to combine the features of both. Raw NDs were used as modifiers of sensors due to the electrocatalytic effect of the sp2 and oxygenated species present on their surface. The aim of this research work is evaluating the applicability of NDs modified with silver (Ag@NDs) and gold (Au@NDs) nanoparticles for the development of a suitable (bio)sensing platform. A complete morphological and electrochemical characterization as a function of the prepared nanocomposite composition was performed in order to improve the electroanalytical properties of the developed (bio)sensors. In the present work, the optimal composition for Au@NDs present on the nanocomposite matrix is 3.5% and the one for Ag@NDs is 1%. Good results were obtained in the evaluation of the optimal composition towards hydrogen peroxide and glucose as a model analyte using a (bio)sensor based on graphite-epoxy-Ag@NDs (17:82:1).
Triboelectric Characterization of Colloidal TiO2 for Energy Harvesting Applications
Authors: Garofalo Erik , Cecchini Luca , Bevione Matteo , Chiolerio Alessandro
Published: June 2020

Nowadays, energy-related issues are of paramount importance. Every energy transformation process results in the production of waste heat that can be harvested and reused, representing an ecological and economic opportunity. Waste heat to power (WHP) is the process of converting the waste heat into electricity. A novel approach is proposed based on the employment of liquid nano colloids. In this work, the triboelectric characterization of TiO2 nanoparticles dispersed in pure water and flowing in a fluorinated ethylene propylene (FEP) pipe was conducted. The idea is to exploit the waste heat to generate the motion of colloidal TiO2 through a FEP pipe. By placing an Al ring electrode in contact with the pipe, it was possible to accumulate electrostatic charges due to the triboelectric effect between the fluid and the inner pipe walls. A peristaltic pump was used to drive and control the flow in order to evaluate the performances in a broad fluid dynamic spectrum. The system generated as output relatively high voltages and low currents, resulting in extracted power ranging between 0.4 and 0.6 nW. By comparing the power of pressure loss due to friction with the extracted power, the electro-kinetic efficiency was estimated to be 20%.
Graphene Oxide Protected Copper Benzene-1,3,5-Tricarboxylate for Clean Energy Gas Adsorption
Authors: Domán Andrea , Klébert Szilvia , Madarász János , Sáfrán György , Wang Ying , László Krisztina
Published: June 2020

Among microporous storage materials copper benzene-1,3,5-tricarboxylate (CuBTC MOF, Cu3(BTC)2 or HKUST-1) holds the greatest potential for clean energy gases. However, its usefulness is challenged by water vapor, either in the gas to be stored or in the environment. To determine the protection potential of graphene oxide (GO) HKUST-1@GO composites containing 0–25% GO were synthesized and studied. In the highest concentration, GO was found to strongly affect HKUST-1 crystal growth in solvothermal conditions by increasing the pH of the reaction mixture. Otherwise, the GO content had practically no influence on the H2, CH4 and CO2 storage capacities, which were very similar to those from the findings of other groups. The water vapor resistance of a selected composite was compared to that of HKUST-1. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric (TG/DTG) and N2 adsorption techniques were used to monitor the changes in the crystal and pore structure. It was found that GO saves the copper–carboxyl coordination bonds by sacrificing the ester groups, formed during the solvothermal synthesis, between ethanol and the carboxyl groups on the GO sheets.
Gold Nanoparticle-Assisted Virus Formation by Means of the Delivery of an Oncolytic Adenovirus Genome
Authors: Sendra Luis , Miguel Antonio , Navarro-Plaza M. Carmen , Herrero María José , de la Higuera José , Cháfer-Pericás Consuelo , Aznar Elena , Marcos M. Dolores , Martínez-Máñez Ramón , Rojas Luis Alfonso , Alemany Ramón , Aliño Salvador F.
Published: June 2020

Oncolytic adenoviruses are a therapeutic alternative to treat cancer based on their ability to replicate selectively in tumor cells. However, their use is limited mainly by the neutralizing antibody (Nab) immune response that prevents repeated dosing. An alternative to facilitate the DNA access to the tumor even in the presence of anti-viral Nabs could be gold nanoparticles able to transfer DNA molecules. However, the ability of these nanoparticles to carry large DNA molecules, such as an oncolytic adenovirus genome, has not been studied. In this work, gold nanoparticles were functionalized with different amounts of polyethylenimine to transfer in a safe and efficient manner a large oncolytic virus genome. Their transfer efficacy and final effect of the oncolytic virus in cancer cells are studied. For each synthesized nanoparticle, (a) DNA loading capacity, (b) complex size, (c) DNA protection ability, (d) transfection efficacy and (e) cytotoxic effect were studied. We observed that small gold nanoparticles (70–80 nm in diameter) protected DNA against nucleases and were able to transfect the ICOVIR-15 oncolytic virus genome encoded in pLR1 plasmid. In the present work, efficient transgene RNA expression, luciferase activity and viral cytopathic effect on cancer cells are reported. These results suggest gold nanoparticles to be an efficient and safe vector for oncolytic adenovirus genome transfer.
Novel Application of Hybrid Anion Exchange Resin for Phosphate Desorption Kinetics in Soils: Minimizing Re-Adsorption of Desorbed Ions
Authors: Li Zhe , Xu Suwei , Li Ying , Arai Yuji
Published: June 2020

The process of phosphate desorption from soils is difficult to measure using stirred batch techniques because of the accumulation of desorbed ions in a bathing solution. To accurately measure the apparent rate coefficient of phosphate desorption from soils, it is necessary to remove the desorbed ions. In this study, a novel hybrid (i.e., iron oxide coated) anion exchange resin was used as a sink to study long-term (seven days) P desorption kinetics in intensively managed agricultural soils in the Midwestern U.S. (total phosphorus (TP): 196–419 mg/kg). The phosphate desorption kinetics in the hybrid anion exchange resin method were compared with those in the other conventional batch desorption method with pure anion exchange resins or without any sink. The extent of P desorption in the hybrid resin methods was >50% of total desorbed phosphate in the other methods. The initial kinetic rate estimated in the pseudo-second-order kinetic model was also highest (3.03–31.35 mg/(g·hr)) in the hybrid resin method when the same soil system was compared. This is because adsorbed P in the hybrid resins was nearly irreversible. The hybrid anion exchange resin might be a new and ideal sink in measuring the P desorption process in soils and sediments.
Cyclin-Dependent Kinases 8 and 19 Regulate Host Cell Metabolism during Dengue Virus Serotype 2 Infection
Authors: Butler Molly , Chotiwan Nunya , Brewster Connie D. , DiLisio James E. , Ackart David F. , Podell Brendan K. , Basaraba Randall J. , Perera Rushika , Quackenbush Sandra L. , Rovnak Joel
Published: June 2020

Dengue virus infection is associated with the upregulation of metabolic pathways within infected cells. This effect is common to infection by a broad array of viruses. These metabolic changes, including increased glucose metabolism, oxidative phosphorylation and autophagy, support the demands of viral genome replication and infectious particle formation. The mechanisms by which these changes occur are known to be, in part, directed by viral nonstructural proteins that contact and control cellular structures and metabolic enzymes. We investigated the roles of host proteins with overarching control of metabolic processes, the transcriptional regulators, cyclin-dependent kinase 8 (CDK8) and its paralog, CDK19, as mediators of virally induced metabolic changes. Here, we show that expression of CDK8, but not CDK19, is increased during dengue virus infection in Huh7 human hepatocellular carcinoma cells, although both are required for efficient viral replication. Chemical inhibition of CDK8 and CDK19 with Senexin A during infection blocks virus-induced expression of select metabolic and autophagic genes, hexokinase 2 (HK2) and microtubule-associated protein 1 light chain 3 (LC3), and reduces viral genome replication and infectious particle production. The results further define the dependence of virus replication on increased metabolic capacity in target cells and identify CDK8 and CDK19 as master regulators of key metabolic genes. The common inhibition of CDK8 and CDK19 offers a host-directed therapeutic intervention that is unlikely to be overcome by viral evolution.
Russian economy on the background of global pandemics: the basic contours of «new reality»
Authors: Smotritskaya I.I.
Published: June 2020

The article deals with conceptual issues related to the adaptation of the Russian economy to the new financial and economic reality that is emerging as a result of the COVID-19 epidemic. The current state of the world economy is studied, the main characteristic features of the «new reality» are highlighted, and the complex of anti-crisis measures implemented in the US and the EU is considered. The results of forecast assessments of the consequences of the pandemic for the economy of our country in the short and long term are analyzed; the principles, priorities and vectors of post-crisis development of the Russian economy are substantiated.
Development of the sub-process of managing relations with the public in the organization
Authors: Astafieva N.S.
Published: June 2020

The process of information management is very relevant for the formation, maintenance and development of any organization’s activities. Special attention is paid to the implementation of the public relations management sub-process. The problems of functioning of the public relations management sub-process are identified, as well as proposals for its development are developed. To improve the effectiveness of the organization’s activities in the local and global market, the technology of the public relations management sub-process is presented.
Regional Treasury: problems of managing property and financial assets
Authors: Kozlova S.V. , Karavaeva I.V.
Published: June 2020

The article deals with a range of issues related to the formation and development of the institutional environment for managing the state (municipal) Treasury. As a result of the research, three models of regional Treasury management were identified. The article describes their characteristics in the context of property and financial assets and their management mechanisms. The article considers the aspect of effective management of the state (municipal) Treasury from the point of view of the level of development of the institutional environment.
Problems of formation of intangible assets in trading systems on the example of X5 Retail Group
Authors: Cheglov V.P. , Platonova Yu.V.
Published: June 2020

The article deals with the features of formation and evaluation of intangible assets in network retail trade, their role as a resource for the development of retail networks. The established criteria for classifying retail network assets as intangible assets and their compliance with current practice are investigated. The structure of intangible assets is analyzed using the example of X5 Retail Group. The possibilities of evaluating a portfolio of long-term lease agreements for retail space as an asset of a retail network are considered. Methodological approaches to the valuation of certain types of intangible assets, in particular their own brands, are proposed.