bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective Heuristic Algorithms Solving the Jobshop Scheduling Problem with Release Dates
Authors: Ren Tao , Zhang Yan , Cheng Shuenn-Ren , Wu Chin-Chia , Zhang Meng , Chang Bo-yu , Wang Xin-yue , Zhao Peng
Published: July 2020

Manufacturing industry reflects a country’s productivity level and occupies an important share in the national economy of developed countries in the world. Jobshop scheduling (JSS) model originates from modern manufacturing, in which a number of tasks are executed individually on a series of processors following their preset processing routes. This study addresses a JSS problem with the criterion of minimizing total quadratic completion time (TQCT), where each task is available at its own release date. Constructive heuristic and meta-heuristic algorithms are introduced to handle different scale instances as the problem is NP-hard. Given that the shortest-processing-time (SPT)-based heuristic and dense scheduling rule are effective for the TQCT criterion and the JSS problem, respectively, an innovative heuristic combining SPT and dense scheduling rule is put forward to provide feasible solutions for large-scale instances. A preemptive single-machine-based lower bound is designed to estimate the optimal schedule and reveal the performance of the heuristic. Differential evolution algorithm is a global search algorithm on the basis of population, which has the advantages of simple structure, strong robustness, fast convergence, and easy implementation. Therefore, a hybrid discrete differential evolution (HDDE) algorithm is presented to obtain near-optimal solutions for medium-scale instances, where multi-point insertion and a local search scheme enhance the quality of final solutions. The superiority of the HDDE algorithm is highlighted by contrast experiments with population-based meta-heuristics, i.e., ant colony optimization (ACO), particle swarm optimization (PSO) and genetic algorithm (GA). Average gaps 45.62, 63.38 and 188.46 between HDDE with ACO, PSO and GA, respectively, are demonstrated by the numerical results with benchmark data, which reveals the domination of the proposed HDDE algorithm.
Comparison of Circular Symmetric Low-Pass Digital IIR Filter Design Using Evolutionary Computation Techniques
Authors: Avalos Omar , Cuevas Erik , Gálvez Jorge , Houssein Essam H. , Hussain Kashif
Published: July 2020

The design of two-dimensional Infinite Impulse Response (2D-IIR) filters has recently attracted attention in several areas of engineering because of their wide range of applications. Synthesizing a user-defined filter in a 2D-IIR structure can be interpreted as an optimization problem. However, since 2D-IIR filters can easily produce unstable transfer functions, they tend to compose multimodal error surfaces, which are computationally difficult to optimize. On the other hand, Evolutionary Computation (EC) algorithms are well-known global optimization methods with the capacity to explore complex search spaces for a suitable solution. Every EC technique holds distinctive attributes to properly satisfy particular requirements of specific problems. Hence, a particular EC algorithm is not able to solve all problems adequately. To determine the advantages and flaws of EC techniques, their correct evaluation is a critical task in the computational intelligence community. Furthermore, EC algorithms are stochastic processes with random operations. Under such conditions, for obtaining significant conclusions, appropriate statistical methods must be considered. Although several comparisons among EC methods have been reported in the literature, their conclusions are based on a set of synthetic functions, without considering the context of the problem or appropriate statistical treatment. This paper presents a comparative study of various EC techniques currently in use employed for designing 2D-IIR digital filters. The results of several experiments are presented and statistically analyzed.
Design of Manufacturing Lines Using the Reconfigurability Principle
Authors: Vavrík Vladimír , Gregor Milan , Grznár Patrik , Mozol Štefan , Schickerle Marek , Ďurica Lukáš , Marschall Martin , Bielik Tomáš
Published: July 2020

Nowadays, many factories face changes on the global market and manufacturing is unpredictable. This fact creates a demand for developing new concepts of the factory which can represent a solution to these changes. This study presents a way for designing these new factory concepts, particularly a concept of the reconfigurable manufacturing lines. The methodology in this study uses characteristics of reconfigurable manufacturing systems for developing an algorithm for designing the basic factory layout. The methodology also combines classical math operations for designing the production layout with such approaches as simulation, cluster analysis, and LCS algorithm. This combination method with LCS algorithm and an entirely different approach to the design of the manufacturing line, has not yet been used. The accuracy of this methodology is then verified through the results of the complete algorithm containing these features. The main purpose of this study was to find new approaches to designing the reconfigurable factory layout. This article is presenting new ways that differ from the classical design method. The article suggests the new way is possible and the new systems also need new ways for designing and planning.
Application of the Kernel Density Function for the Analysis of Regional Growth and Convergence in the Service Sector through Productivity
Authors: Correa-Quezada Ronny , Cueva-Rodríguez Lucía , Álvarez-García José , del Río-Rama María de la Cruz
Published: July 2020

The aim of this research work is to analyze growth and convergence processes in the service sector and its large groups, market, and non-market services, at the regional level in Ecuador by taking the labor productivity variable as a reference. The methodology used is an analysis of distributive dynamics of the data, applying the non-parametric method of Kernel density functions from a mathematical economics approach. The results obtained show that the service sector has non-alarming levels of inequality, its trend over time is increasing. When disaggregating the data, it was observed that non-market services show a rapid growth in inequality. In contrast, market services show greater stability during the period analyzed. Regarding intra-distribution dynamics for the service sector and its subsectors, in the long term, poor regions improve, while rich regions deteriorate. However, deterioration of advanced regions is less intense in non-market services.
Protective Effect of Astaxanthin on Blue Light Light-Emitting Diode-Induced Retinal Cell Damage via Free Radical Scavenging and Activation of PI3K/Akt/Nrf2 Pathway in 661W Cell Model
Authors: Lin Chao-Wen , Yang Chung-May , Yang Chang-Hao
Published: July 2020

Light-emitting diodes (LEDs) are widely used and energy-efficient light sources in modern life that emit higher levels of short-wavelength blue light. Excessive blue light exposure may damage the photoreceptor cells in our eyes. Astaxanthin, a xanthophyll that is abundantly available in seafood, is a potent free radical scavenger and anti-inflammatory agent. We used a 661W photoreceptor cell line to investigate the protective effect of astaxanthin on blue light LED-induced retinal injury. The cells were treated with various concentrations of astaxanthin and then exposed to blue light LED. Our results showed that pretreatment with astaxanthin inhibited blue light LED-induced cell apoptosis and prevented cell death. Moreover, the protective effect was concentration dependent. Astaxanthin suppressed the production of reactive oxygen species and oxidative stress biomarkers and diminished mitochondrial damage induced by blue light exposure. Western blot analysis confirmed that astaxanthin activated the PI3K/Akt pathway, induced the nuclear translocation of Nrf2, and increased the expression of phase II antioxidant enzymes. The expression of antioxidant enzymes and the suppression of apoptosis-related proteins eventually protected the 661W cells against blue light LED-induced cell damage. Thus, our results demonstrated that astaxanthin exerted a dose-dependent protective effect on photoreceptor cells against damage mediated by blue light LED exposure.
How Dietary Factors Affect DNA Methylation: Lesson from Epidemiological Studies
Authors: Maugeri Andrea , Barchitta Martina
Published: July 2020

Over the past decades, DNA methylation has been proposed as a molecular mechanism underlying the positive or negative effects of diet on human health. Despite the number of studies on this topic is rapidly increasing, the relationship between dietary factors, changes in DNA methylation and health outcomes remains unclear. In this review, we summarize the literature from observational studies (cross-sectional, retrospective, or prospective) which examined the association of dietary factors (nutrients, foods, and dietary patterns) with DNA methylation markers among diseased or healthy people during the lifetime. Next, we discuss the methodological pitfalls by examining strengths and limitations of published studies. Finally, we close with a discussion on future challenges of this field of research, raising the need for large-size prospective studies evaluating the association between diet and DNA methylation in health and diseases for appropriate public health strategies.
The Influence of Electric Field Intensity and Particle Length on the Electrokinetic Transport of Cylindrical Particles Passing through Nanopore
Authors: Shi Liuyong , He Xiaohan , Ge Jian , Zhou Teng , Li Ting , Joo Sang Woo
Published: July 2020

The electric transport of nanoparticles passing through nanopores leads to a change in the ion current, which is essential for the detection technology of DNA sequencing and protein determination. In order to further illustrate the electrokinetic transport mechanism of particles passing through nanopores, a fully coupled continuum model is constructed by using the arbitrary Lagrangian–Eulerian (ALE) method. The model consists of the electric field described by the Poisson equation, the concentration field described by Nernst–Planck equation, and the flow field described by the Navier–Stokes equation. Based on this model, the influence of imposed electric field and particle length on the electrokinetic transport of cylindrical particles is investigated. It is found firstly the translation velocities for the longer particles remain constant when they locate inside the nanopore. Both the ion current blockade effect and the ion current enhancement effect occur when cylindrical particles enter and exit the nanopore, respectively, for the experimental parameters employed in this research. Moreover, the particle translation velocity and current fluctuation amplitude are dominated by the electric field intensity, which can be used to adjust the particle transmission efficiency and the ion current detectability. In addition, the increase in particle length changes the particle position corresponding to the peak value of the ion current, which contributes to distinguishing particles with different lengths as well.
Multi-Physics Fields Based Nonlinear Dynamic Behavior Analysis of Air Bearing Motorized Spindle
Authors: Chen Guoda , Chen Yijie , Lu Qi , Wu Quanhui , Wang Minghuan
Published: July 2020

The air bearing motorized spindle (ABMS) is the key component of the ultra-precision machine tool, which plays an important role in the ultra-precision machining process and directly influences machining accuracy. The influence of unbalanced magnetic force (UMF) on the nonlinear dynamic behavior of the ABMS is not understood clearly. To reveal the potential influence of the UMF, a mathematical model of the ABMS considering multiphysics fields is established. The variation trend of the UMF is simulated, and the nonlinear dynamic behavior of the ABMS is analyzed which emphasizes on the stability of the rotating shaft. It is shown that the UMF varies linearly at large rotor eccentricity which meets well with previous research, but it is noteworthy the UMF varies nearly to a quadratic function at small rotor eccentricity. The result of rotor dynamics shows that the UMF can change the converge position of the rotor center and the converge speed. Moreover, when at certain rotor mass and external load, the UMF can enlarge the stability boundary of the rotor. This research provides an example of analyzing the nonlinear dynamic behavior of the ABMS considering multiphysics fields which may help to the further investigation.
Experimental Investigation on a Novel Airfoil-Based Piezoelectric Energy Harvester for Aeroelastic Vibration
Authors: Shan Xiaobiao , Tian Haigang , Cao Han , Feng Ju , Xie Tao
Published: July 2020

This paper presents a novel airfoil-based piezoelectric energy harvester (EH) with two small square prisms attached to an airfoil. This harvester can achieve a two degree-of-freedom (DOF) plunge–pitch motions. Several prototypes of energy harvester were fabricated to explore the nonlinear aerodynamic response and the output performance in a wind tunnel. The experimental results showed that the longer the flexible spring was, the lower the critical velocity and frequency of the harvester were, and the better aerodynamic response and output performance could be achieved. The initial disturbance, the following limit-cycle oscillation, and the ultimate chaos of nonlinear response occurred, as increasing airflow velocity was increased. The overall output performance of the harvesters with a flexible spring having a thickness of 1 mm outperformed than that of the harvesters with a flexible spring having a thickness of 0.5 mm at a higher airflow velocity, while the tendency was opposite at a lower velocity. An optimum output voltage of 17.48 V and a power of 0.764 mW were harvested for EH-160-1 at 16.32 m/s, which demonstrated it possessed better performance than the other harvesters. When the capacitor was charged for 45 s and directly drove a sensor, it could maintain working for 17 s to display temperature and humidity in real time.
The Infant Gut Microbiota and Risk of Asthma: The Effect of Maternal Nutrition during Pregnancy and Lactation
Authors: Alsharairi Naser A.
Published: July 2020

Research has amply demonstrated that early life dysbiosis of the gut microbiota influences the propensity to develop asthma. The influence of maternal nutrition on infant gut microbiota is therefore of growing interest. However, a handful of prospective studies have examined the role of maternal dietary patterns during pregnancy in influencing the infant gut microbiota but did not assess whether this resulted in an increased risk of asthma later in life. The mechanisms involved in the process are also, thus far, poorly documented. There have also been few studies examining the effect of maternal dietary nutrient intake during lactation on the milk microbiota, the effect on the infant gut microbiota and, furthermore, the consequences for asthma development remain largely unknown. Therefore, the specific aim of this mini review is summarizing the current knowledge regarding the effect of maternal nutrition during pregnancy and lactation on the infant gut microbiota composition, and whether it has implications for asthma development.
Production of Marine Probiotic Bacteria in a Cost-Effective Marine Media Based on Peptones Obtained from Discarded Fish By-Products
Authors: Vázquez José Antonio , Durán Ana , Nogueira Margarita , Menduíña Araceli , Antunes Joana , Freitas Ana Cristina , Gomes Ana María
Published: July 2020

The industrial production of marine bacteria with probiotic properties is limited by the excessive cost of the culture media adequate for their growth. The present work aimed to study the suitability of 30 marine media formulated with nitrogen sources (fish peptones) from different fish discards and seawater, for the growth of two marine probiotic bacteria (MPB), namely Phaeobacter sp. and Pseudomonas fluorescens. These fish peptones were produced from several discarded fish and by-products (heads, skins, and whole individuals of megrim, mackerel, gurnard, hake, etc.). In all cultivations, no significant differences were found on cell viability when the microorganism grew on commercial or alternative media. In relation to the biomass production, the growth of Phaeobacter sp. on waste media was commonly similar or a 20% lower than observed in the control cultures. For P. fluorescens, various peptones (skin peptones of pouting and blue whiting) showed even higher productive ability than commercial peptones. An initial economical evaluation revealed that low-cost media reduced until 120 times the cost of production of MPB.
High-Performance Recovery of Cobalt and Nickel from the Cathode Materials of NMC Type Li-Ion Battery by Complexation-Assisted Solvent Extraction
Authors: Wang Wen-Yu , Yang Hong-Chi , Xu Ren-Bin
Published: July 2020

The annual global volume of waste lithium-ion batteries (LIBs) has been increasing over years. Although solvent extraction method seems well developed, the separation factor between cobalt and nickel is still relatively low—only 72 when applying conventional continuous-countercurrent extraction. In this study, we improved the separation factor of cobalt and nickel by complexation-assisted solvent extraction. Before solvent extraction procedure, leaching kinetic of Li, Ni, Co and Mn was studied and can be explained by the Avrami equation. Leached residues were also investigated by SEM and XRD. Operation parameters of complexation-assisted solvent extraction were examined, including volume ratio of extractant to diluent, types of diluent, type of complexing reagent, extractant saponification percentage and volume ratio of organic phase to aqueous phase. The optimal separation factor of complexation-assisted solvent extraction could be improved to 372, which is five times that of conventional solvent extraction. The separation tendency would be interpreted by the relationship between extraction equilibrium pH and log distribution coefficient.
Fluid Evolution, H-O Isotope and Re-Os Age of Molybdenite from the Baiyinhan Tungsten Deposit in the Eastern Central Asian Orogenic Belt, NE China, and Its Geological Significance
Authors: Wang Ruiliang , Zeng Qingdong , Zhang Zhaochong , Guo Yunpeng , Lu Jinhang
Published: July 2020

The quartz-vein-type Baiyinhan tungsten deposit is located at the eastern part of the Central Asian Orogenic Belt, NE China. Analyses of fluid inclusions, H-O isotope of quartz and Re-Os isotope of molybdenite were carried out. Three stages of mineralization were identified: The early quartz + wolframite + bismuth stage, the middle quartz + molybdenite stage and the late calcite + fluorite stage. Quartz veins formed in the three stages were selected for the fluid inclusion analysis. The petrographic observation and fluid inclusion microthermometry results revealed three types of fluid inclusions: CO2-H2O (C-type), liquid-rich (L-type) and vapor-rich (V-type). The homogenization temperatures of C-type, V-type and L-type inclusions were 233–374 °C, 210–312 °C, and 196–311 °C, respectively. The salinity of the three types of inclusions was identical, varying in the range of 5–12 wt%. The H-O isotope analyses results showed that quartz had δ18OH2O and δDSMOW compositions of −2.6‰ to 4.3‰ and −97‰ to −82‰, respectively, indicating that the ore-forming fluids were mainly derived from magmatic water with a minor contribution of meteoric water. The addition of meteoric water reduces the temperature and salinity of the ore-forming fluids, which leads to a decrease of the solubility of tungsten and molybdenum in the fluids and eventually the precipitation of minerals. Re-Os isotopic analysis of five molybdenite samples yielded an isochron age of 139.6 ± 7.6 Ma (2σ) with an initial 187Os of −0.05 ± 0.57 (MSWD = 3.5). Rhenium concentrations of the molybdenite samples were between 3.1 ug/g and 8.5 ug/g. The results suggest that the metals of the Baiyinhan deposit have a crust origin, and the mineralization is one episode of the Early Cretaceous tungsten mineralization epoch which occurred at the eastern part of the Central Asian Orogenic Belt.
Role of Mg Impurity in the Water Adsorption over Low-Index Surfaces of Calcium Silicates: A DFT-D Study
Authors: Qi Chongchong , Chen Qiusong , Fourie Andy
Published: July 2020

Calcium silicates are the most predominant phases in ordinary Portland cement, inside which magnesium is one of the momentous impurities. In this work, using the first-principles density functional theory (DFT), the impurity formation energy (Efor) of Mg substituting Ca was calculated. The adsorption energy (Ead) and configuration of the single water molecule over Mg-doped β-dicalcium silicate (β-C2S) and M3-tricalcium silicate (M3-C3S) surfaces were investigated. The obtained Mg-doped results were compared with the pristine results to reveal the impact of Mg doping. The results show that the Efor was positive for all but one of the calcium silicates surfaces (ranged from −0.02 eV to 1.58 eV), indicating the Mg substituting for Ca was not energetically favorable. The Ead of a water molecule on Mg-doped β-C2S surfaces ranged from –0.598 eV to −1.249 eV with the molecular adsorption being the energetically favorable form. In contrast, the Ead on M3-C3S surfaces ranged from −0.699 eV to −4.008 eV and the more energetically favorable adsorption on M3-C3S surfaces was dissociative adsorption. The influence of Mg doping was important since it affected the reactivity of surface Ca/Mg sites, the Ead of the single water adsorption, as well as the adsorption configuration compared with the water adsorption on pristine surfaces.
Design, Synthesis, and Acaricidal Activity of Phenyl Methoxyacrylates Containing 2-Alkenylthiopyrimidine
Authors: Hao Shulin , Cai Zengfei , Cao Yangyang , Du Xiaohua
Published: July 2020

A series of novel phenyl methoxyacrylate derivatives containing a 2-alkenylthiopyrimidine substructure were designed, synthesized, and evaluated in terms of acaricidal activity. The structures of the title compounds were identified by 1H NMR, 13C NMR and high-resolution mass spectra (HRMS). Compound (E)-methyl 2-(2-((2-(3,3-dichloroallylthio)-6-(trifluoromethyl)pyrimidin-4-yloxy)methyl)phenyl)-3-methoxyacr-ylate (4j) exhibited significant acaricidal activity against Tetranychus cinnabarinus (T. cinnabarinus) in greenhouse tests possessing nearly twice the larvicidal and ovicidal activity compared to fluacrypyrim. Furthermore, the results of the field trials demonstrated that compound 4j could effectively control Panonychuscitri with long-lasting persistence and rapid action. The toxicology data in terms of LD50 value confirmed that compound 4j has a relatively low acute toxicity to mammals, birds, and honeybees.
Intracellular Hydrolysis of Small-Molecule O-Linked N-Acetylglucosamine Transferase Inhibitors Differs among Cells and Is Not Required for Its Inhibition
Authors: Loi Elena Maria , Weiss Matjaž , Pajk Stane , Gobec Martina , Tomašič Tihomir , Pieters Roland J. , Anderluh Marko
Published: July 2020

O-GlcNAcylation is an essential post-translational modification that occurs on nuclear and cytoplasmic proteins, regulating their function in response to cellular stress and altered nutrient availability. O-GlcNAc transferase (OGT) is the enzyme that catalyzes this reaction and represents a potential therapeutic target, whose biological role is still not fully understood. To support this research field, a series of cell-permeable, low-nanomolar OGT inhibitors were recently reported. In this study, we resynthesized the most potent OGT inhibitor of the library, OSMI-4, and we used it to investigate OGT inhibition in different human cell lines. The compound features an ethyl ester moiety that is supposed to be cleaved by carboxylesterases to generate its active metabolite. Our LC-HRMS analysis of the cell lysates shows that this is not always the case and that, even in the cell lines where hydrolysis does not occur, OGT activity is inhibited.
Effects of Foam Microbubbles on Electrical Resistivity and Capillary Pressure of Partially Saturated Porous Media
Authors: R. Adebayo Abdulrauf , Isah Abubakar , Mahmoud Mohamed , Al-Shehri Dhafer
Published: July 2020

Laboratory measurements of capillary pressure (Pc) and the electrical resistivity index (RI) of reservoir rocks are used to calibrate well logging tools and to determine reservoir fluid distribution. Significant studies on the methods and factors affecting these measurements in rocks containing oil, gas, and water are adequately reported in the literature. However, with the advent of chemical enhanced oil recovery (EOR) methods, surfactants are mixed with injection fluids to generate foam to enhance the gas injection process. Foam is a complex and non-Newtonian fluid whose behavior in porous media is different from conventional reservoir fluids. As a result, the effect of foam on Pc and the reliability of using known rock models such as the Archie equation to fit experimental resistivity data in rocks containing foam are yet to be ascertained. In this study, we investigated the effect of foam on the behavior of both Pc and RI curves in sandstone and carbonate rocks using both porous plate and two-pole resistivity methods at ambient temperature. Our results consistently showed that for a given water saturation (Sw), the RI of a rock increases in the presence of foam than without foam. We found that, below a critical Sw, the resistivity of a rock containing foam continues to rise rapidly. We argue, based on knowledge of foam behavior in porous media, that this critical Sw represents the regime where the foam texture begins to become finer, and it is dependent on the properties of the rock and the foam. Nonetheless, the Archie model fits the experimental data of the rocks but with resulting saturation exponents that are higher than conventional gas–water rock systems. The degree of variation in the saturation exponents between the two fluid systems also depends on the rock and fluid properties. A theory is presented to explain this phenomenon. We also found that foam affects the saturation exponent in a similar way as oil-wet rocks in the sense that they decrease the cross-sectional area of water available in the pores for current flow. Foam appears to have competing and opposite effects caused by the presence of clay, micropores, and conducting minerals, which tend to lower the saturation exponent at low Sw. Finally, the Pc curve is consistently lower in foam than without foam for the same Sw.
Guided User Research Methods for Experience Design—A New Approach to Focus Groups and Cultural Probes
Authors: Krueger Anne Elisabeth , Pollmann Kathrin , Fronemann Nora , Foucault Beatrice
Published: July 2020

Many companies are facing the task for radical innovations—totally new concepts and ideas for products and services, which are successful at the market. One major factor for success is a positive user experience. Thus, design teams need, and are challenged to integrate, an experience-centered perspective in their human-centered design processes. To support this, we propose adjusted versions of the well-established user research methods focus groups and cultural probes, in order to tailor them to the specific needs and focus of experience-based design, especially in the context of solving “wicked design problems”. The results are experience focus groups and experience probes, which augment the traditional methods with new structuring, materials, and tasks based on the three principles experience focus, creative visualization, and systematic guidance. We introduce and describe a two step-approach for applying these methods, as well as a case study that was conducted in cooperation with a company that illustrates how the methods can be applied to enable an experience-centered perspective on the topic of “families and digital life”. The case study demonstrates how the methods address the three principles they are based on. Post-study interviews with representatives of the company revealed valuable insights about their usefulness for practical user experience design.
Relationship between Nanomechanical Responses of Interfacial Intermetallic Compound Layers and Impact Reliability of Solder Joints
Authors: Song Jenn-Ming , Huang Bo-Chang , Tarng David , Hung Chih-Pin , Yasuda Kiyokazu
Published: July 2020

This study aims to evaluate solder joint reliability under high speed impact tests using nanoindentation properties of intermetallic compounds (IMCs) at the joint interface. Sn–Ag based solder joints with different kinds of interfacial IMCs were obtained through the design of solder alloy/substrate material combinations. Nanoindentation was applied to investigate the mechanical properties of IMCs, including hardness, Young’s modulus, work hardening exponent, yield strength, and plastic ability. Experimental results suggest that nanoindentation responses of IMCs at joint interface definitely dominates joint impact performance. The greater the plastic ability the interfacial IMC exhibits, the superior impact energy the solder joints possess. The concept of mechanical and geometrical discontinuities was also proposed to explain brittle fracture of the solder joints with bi-layer interfacial IMCs subject to impact load.
Photocatalytic Degradation of Tetracycline by ZnO/γ-Fe2O3 Paramagnetic Nanocomposite Material
Authors: Semeraro Paola , Bettini Simona , Sawalha Shadi , Pal Sudipto , Licciulli Antonio , Marzo Fabio , Lovergine Nicola , Valli Ludovico , Giancane Gabriele
Published: July 2020

In recent years, the presence of numerous xenobiotic substances, such as antibiotics, has been detected in water environments. They can be considered as environmental contaminants, even if their effect on human health has yet to be totally understood. Several approaches have been studied for the removal of these kinds of pollutants. Among these compounds, tetracycline (TC), a broad-spectrum antibiotic, is one of the most commonly found in water due to its widespread use. In the context of reducing the presence of TC in aqueous solution, in this contribution, a composite catalyst based on zinc oxide (ZnO) and iron oxide (γ-Fe2O3) was developed and its photocatalytic properties were investigated. The catalytic materials were synthesized by a microwave-assisted aqueous solution method and characterized by Field Emission Scanning Electron Microscope (FESEM), X-Ray Fluorescence (XRF) and Brunauer−Emmett−Teller (BET) analysis. The TC concentration was evaluated by spectrophotometer measurements at specific time intervals. The performed photocatalytic experiments clearly demonstrated that the ZnO/γ-Fe2O3 composite catalyst presents significant photocatalytic activity, indeed a TC degradation efficiency of 88.52% was registered after 150 min. The presence of iron oxide in the structure of the catalyst enhances both the surface area and the pore volume, facilitating the adsorption of the analyte on the surface of nanostructures, a fundamental phase to optimize a photodegradation process. Moreover, ZnO was found to play the key role in the photocatalytic process assisted by γ-Fe2O3 which enhanced the TC degradation efficiency by 20%.
Internal Surface Plasmon Excitation as the Root Cause of Laser-Induced Periodic Plasma Structure and Self-Organized Nanograting Formation in the Volume of Transparent Dielectric
Authors: Gildenburg Vladimir B. , Pavlichenko Ivan A.
Published: July 2020

A computer simulation of the dynamics of an optical discharge produced in the volume of a transparent dielectric (fused silica) by a focused femtosecond laser pulse was carried out taking into account the possibility of developing small-scale ionization-field instability. The presence of small foreign inclusions in the fused silica was taken into account with the model of a nanodispersed heterogeneous medium by using Maxwell Garnett formulas. The results of the calculations made it possible to reveal the previously unknown physical mechanism that determines the periodicity of the ordered plasma-field structure that is formed in each single breakdown pulse and is the root cause of the ordered volume nanograting formation in dielectric material exposed to a series of repeated pulses. Two main points are decisive in this mechanism: (i) the formation of a thin overcritical plasma layer at the breakdown wave front counter-propagated to the incident laser pulse and (ii) the excitation of the “internal surface plasmon” at this front, resulting in a rapid amplification of the corresponding spatial harmonic of random seed perturbations in the plasma and formation of a contrast structure with a period equal to the wavelength of the surface plasmon (0.7 of the wavelength in dielectric).
Effect of Choline Forms and Gut Microbiota Composition on Trimethylamine-N-Oxide Response in Healthy Men
Authors: Cho Clara E. , Aardema Niklas D. J. , Bunnell Madison L. , Larson Deanna P. , Aguilar Sheryl S. , Bergeson Janet R. , Malysheva Olga V. , Caudill Marie A. , Lefevre Michael
Published: July 2020

Background: Trimethylamine-N-oxide (TMAO), a choline-derived gut microbiota-dependent metabolite, is a newly recognized risk marker for cardiovascular disease. We sought to determine: (1) TMAO response to meals containing free versus lipid-soluble choline and (2) effects of gut microbiome on TMAO response. Methods: In a randomized, controlled, double-blinded, crossover study, healthy men (n = 37) were provided meals containing 600 mg choline either as choline bitartrate or phosphatidylcholine, or no choline control. Results: Choline bitartrate yielded three-times greater plasma TMAO AUC (p = 0.01) and 2.5-times greater urinary TMAO change from baseline (p = 0.01) compared to no choline and phosphatidylcholine. Gut microbiota composition differed (permutational multivariate analysis of variance, PERMANOVA; p = 0.01) between high-TMAO producers (with ≥40% increase in urinary TMAO response to choline bitartrate) and low-TMAO producers (with <40% increase in TMAO response). High-TMAO producers had more abundant lineages of Clostridium from Ruminococcaceae and Lachnospiraceae compared to low-TMAO producers (analysis of composition of microbiomes, ANCOM; p < 0.05). Conclusion: Given that phosphatidylcholine is the major form of choline in food, the absence of TMAO elevation with phosphatidylcholine counters arguments that phosphatidylcholine should be avoided due to TMAO-producing characteristics. Further, development of individualized dietary recommendations based on the gut microbiome may be effective in reducing disease risk
Are Adherence to the Mediterranean Diet, Emotional Eating, Alcohol Intake, and Anxiety Related in University Students in Spain?
Authors: Carlos Marchena , Elena Bernabéu , Teresa Iglesias M.
Published: July 2020

Research has suggested that university students are at risk from certain unhealthy habits, such as poor diet or alcohol abuse. At the same time, anxiety levels appear to be higher among university students, which may lead to high levels of emotional eating. The aim of this study was to analyze the degree of adherence to the Mediterranean diet (AMD), emotional eating, alcohol intake, and anxiety among Spanish university students, and the interrelationship of these variables. A total of 252 university students filled out the Mediterranean Diet Quality Index (KIDMED) questionnaire for Mediterranean diet adherence, an Alcohol Use Disorders Identification Test, a State-Trait Anxiety Inventory and the Emotional Eater Questionnaire. We analyzed descriptive data, a t-test and analysis of variance (ANOVA) for differences, a Pearson correlation, and multiple regression tests. Results showed low levels of AMD among university students (15.5%) and considerable levels of emotional eating (29%) and anxiety (23.6%). However, levels of alcohol dependence were low (2.4%). State-anxiety was a predictor of the emotional eater score and its subscales, and sex also was predictive of subscale guilt and the total score. However, AMD was predicted only by trait-anxiety. These models accounted for between 1.9% and 19%. The results suggest the need for the implementation of educational programs to promote healthy habits among university students at risk.
Understanding the Mechanisms of Diet and Outcomes in Colon, Prostate, and Breast Cancer; Malignant Gliomas; and Cancer Patients on Immunotherapy
Authors: Mann Shivtaj , Sidhu Manreet , Gowin Krisstina
Published: July 2020

Cancer patients often ask which foods would be best to consume to improve outcomes. This is a difficult question to answer as there are no case-controlled, prospective studies that control for confounding factors. Therefore, a literature review utilizing PubMed was conducted with the goal to find evidence-based support for certain diets in specific cancer patients—specifically, we reviewed data for colon cancer, prostate cancer, breast cancer, malignant gliomas, and cancer patients on immunotherapy. Improved outcomes in colon cancer and patients on immunotherapy were found with high-fiber diets. Improved outcomes in malignant gliomas were found with ketogenic diets. Improved outcomes in prostate cancer and breast cancer were found with plant-based diets. However, the data are not conclusive for breast cancer. Additionally, the increased intake of omega-3 fatty acids were also associated with better outcomes for prostate cancer. While current research, especially in humans, is minimal, the studies discussed in this review provide the groundwork for future research to further investigate the role of dietary intervention in improving cancer outcomes.
Adaptive Fat Oxidation Is Coupled with Increased Lipid Storage in Adipose Tissue of Female Mice Fed High Dietary Fat and Sucrose
Authors: Fuller Scott , Yu Yongmei , Allerton Timothy D. , Mendoza Tamra , Ribnicky David M. , Floyd Z. Elizabeth
Published: July 2020

Western diets high in fat and sucrose are associated with metabolic syndrome (MetS). Although the prevalence of MetS in women is comparable to that in men, metabolic adaptations in females to Western diet have not been reported in preclinical studies. This study investigates the effects of Western diet on risk factors for MetS in female mice. Based on our earlier studies in male mice, we hypothesized that dietary supplementation with extracts of Artemisia dracunculus L. (PMI5011) and Momordica charantia (bitter melon) could affect MetS risk factors in females. Eight-week-old female mice were fed a 10% kcal fat, 17% kcal sucrose diet (LFD); high-fat, high-sucrose diet (HFS; 45% kcal fat, 30% kcal sucrose); or HFS diet with PMI5011 or bitter melon for three months. Body weight and adiposity in all HFS groups were greater than the LFD. Total cholesterol level was elevated with the HFS diets along with LDL cholesterol, but triglycerides and free fatty acids were unchanged from the LFD. Over the three month period, female mice responded to the HFS diet by adaptive increases in fat oxidation energy in muscle and liver. This was coupled with increased fat storage in white and brown adipose tissue depots. These responses were enhanced with botanical supplementation and confer protection from ectopic lipid accumulation associated with MetS in female mice fed an HFS diet.
Evolution of Nanotechnology in Delivering Drugs to Eyes, Skin and Wounds via Topical Route
Authors: Koppa Raghu Pratheeksha , Bansal Kuldeep K. , Thakor Pradip , Bhavana Valamla , Madan Jitender , Rosenholm Jessica M. , Mehra Neelesh Kumar
Published: July 2020

The topical route is the most preferred one for administering drugs to eyes, skin and wounds for reaching enhanced efficacy and to improve patient compliance. Topical administration of drugs via conventional dosage forms such as solutions, creams and so forth to the eyes is associated with very low bioavailability (less than 5%) and hence, we cannot rely on these for delivering drugs to eyes more efficiently. An intravitreal injection is another popular drug delivery regime but is associated with complications like intravitreal hemorrhage, retinal detachment, endophthalmitis, and cataracts. The skin has a complex structure that serves as numerous physiological barriers to the entry of exogenous substances. Drug localization is an important aspect of some dermal diseases and requires directed delivery of the active substance to the diseased cells, which is challenging with current approaches. Existing therapies used for wound healing are costly, and they involve long-lasting treatments with 70% chance of recurrence of ulcers. Nanotechnology is a novel and highly potential technology for designing formulations that would improve the efficiency of delivering drugs via the topical route. This review involves a discussion about how nanotechnology-driven drug delivery systems have evolved, and their potential in overcoming the natural barriers for delivering drugs to eyes, skin and wounds.
In Vitro Evaluation of Self-Nano-Emulsifying Drug Delivery Systems (SNEDDS) Containing Room Temperature Ionic Liquids (RTILs) for the Oral Delivery of Amphotericin B
Authors: Kontogiannidou Eleni , Meikopoulos Thomas , Gika Helen , Panteris Emmanuel , Vizirianakis Ioannis S. , Müllertz Anette , Fatouros Dimitrios G.
Published: July 2020

Amphotericin B (AmpB), one of the most commonly used agents in the treatment of severe fungal infections and life-threatening parasitic diseases such as visceral Leishmaniasis, has a negligible oral bioavailability, primarily due to a low solubility and permeability. To develop an oral formulation, medium chain triglycerides and nonionic surfactants in a self-nano-emulsifying drug delivery system (SNEDDS) containing AmpB were combined with room temperature ionic liquids (RTILs) of imidazolium. The presence of ionic liquids significantly enhanced the solubility of AmpB, exhibited a low toxicity and increased the transport of AmpB across Caco-2 cell monolayers. The combination of RTILs with a lipid formulation might be a promising strategy to improve the oral bioavailability of AmpB.
Polymer Nanomedicines with Ph-Sensitive Release of Dexamethasone for the Localized Treatment of Inflammation
Authors: Libánská Alena , Randárová Eva , Lager Franck , Renault Gilles , Scherman Daniel , Etrych Tomáš
Published: July 2020

Polymer-drug conjugates have several advantages in controlled drug delivery to inflammation as they can accumulate and release the drug in inflamed tissues or cells, which could circumvent the shortcomings of current therapy. To improve the therapeutic potential of polymer-drug conjugates in joint inflammation, we synthesized polymer conjugates based on N-(2-hydroxypropyl) methacrylamide) copolymers labeled with a near-infrared fluorescent dye and covalently linked to the anti-inflammatory drug dexamethasone (DEX). The drug was bound to the polymer via a spacer enabling pH-sensitive drug release in conditions mimicking the environment inside inflammation-related cells. An in vivo murine model of adjuvant-induced arthritis was used to confirm the accumulation of polymer conjugates in arthritic joints, which occurred rapidly after conjugate application and remained until the end of the experiment. Several tested dosage schemes of polymer DEX-OPB conjugate showed superior anti-inflammatory efficacy. The highest therapeutic effect was obtained by repeated i.p. application of polymer conjugate (3 × 1 mg/kg of DEX eq.), which led to a reduction in the severity of inflammation in the ankle by more than 90%, compared to 40% in mice treated with free DEX.
Enhanced Corneal Penetration of a Poorly Permeable Drug Using Bioadhesive Multiple Microemulsion Technology
Authors: Ibrahim Mohamed Moustafa , Maria Doaa Nabih , Wang XiangDi , Simpson Raven N. , Hollingsworth T.J. , Jablonski Monica M.
Published: July 2020

Corneal penetration is a key rate limiting step in the bioavailability of topical ophthalmic formulations that incorporate poorly permeable drugs. Recent advances have greatly aided the ocular delivery of such drugs using colloidal drug delivery systems. Ribavirin, a poorly permeable BCS class-III drug, was incorporated in bioadhesive multiple W/O/W microemulsion (ME) to improve its corneal permeability. The drug-loaded ME was evaluated regarding its physical stability, droplet size, PDI, zeta potential, ultrastructure, viscosity, bioadhesion, in vitro release, transcorneal permeability, cytotoxicity, safety and ocular tolerance. Our ME possessed excellent physical stability, as it successfully passed several cycles of centrifugation and freeze–thaw tests. The formulation has a transparent appearance due to its tiny droplet size (10 nm). TEM confirmed ME droplet size and revealed its multilayered structure. In spite of the high aqueous solubility and the low permeability of ribavirin, this unique formulation was capable of sustaining its release for up to 24 h and improving its corneal permeability by 3-fold. The in vitro safety of our ME was proved by its high percentage cell viability, while its in vivo safety was confirmed by the absence of any sign of toxicity or irritation after either a single dose or 14 days of daily dosing. Our ME could serve as a vehicle for enhanced ocular delivery of drugs with different physicochemical properties, including those with low permeability.
Cloaking Using the Anisotropic Multilayer Sphere
Authors: Batool Sidra , Nisar Mehwish , Frezza Fabrizio , Mangini Fabio
Published: July 2020

We studied a Spherically Radially Anisotropic (SRA) multilayer sphere with an arbitrary number of layers. Within each layer permittivity components are different from each other in radial and tangential directions. Under the quasi-static approximation, we developed a more generalized mathematical model that can be used to calculate polarizability of the SRA multilayer sphere with any arbitrary number of layers. Moreover, the functionality of the SRA multilayer sphere as a cloak has been investigated. It has been shown that by choosing a suitable contrast between components of the permittivity, the SRA multilayer sphere can achieve threshold required for invisibility cloaking.
The Influence of the Dilution Rate on the Aggressiveness of Inocula and the Expression of Resistance against Fusarium Head Blight in Wheat
Authors: Toth Beata , Gyorgy Andrea , Varga Monika , Mesterhazy Akos
Published: July 2020

In previous research, conidium concentrations varying between 10,000 and 1,000,000/mL have not been related to any aggressiveness test. Therefore, two Fusarium graminearum and two Fusarium culmorum isolates were tested in the field on seven genotypes highly differing in resistance at no dilution, and 1:1, 1:2, 1:4, 1:8, and 1:16 dilutions in two years (2013 and 2014). The isolates showed different aggressiveness, which changed significantly at different dilution rates for disease index (DI), Fusarium-damaged kernels (FDK), and deoxynivalenol (DON). The traits also had diverging responses to the infection. The effect of the dilution could not be forecasted. The genotype ranks also varied. Dilution seldomly increased aggressiveness, but often lower aggressiveness occurred at high variation. The maximum and minimum values varied between 15% and 40% for traits and dilutions. The reductions between the non-diluted and diluted values (total means) for DI ranged from 6% and 33%, for FDK 8.3–37.7%, and for DON 5.8–44.8%. The most sensitive and most important trait was DON. The introduction of the aggressiveness test provides improved regulation compared to the uncontrolled manipulation of the conidium concentration. The use of more isolates significantly increases the credibility of phenotyping in genetic and cultivar registration studies.