bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Affecting Sustainable Market Acceptance of Residential Microgeneration Technologies. A Two Time Period Comparative Analysis
Authors: Karytsas Spyridon , Vardopoulos Ioannis , Theodoropoulou Eleni
Published: August 2019

On a global scale, the residential sector is responsible for a significant part of consumed energy, of which the major part is dependent upon fossil fuels. A solution for the reduction of fossil fuel use is the application of residential microgeneration technologies. The present study examines the market acceptance factors of such systems in Greece, as well as how these factors change over time, based on real decisions made by consumers. In this context, two surveys applying a common questionnaire were performed in 2012 and 2019 in order to examine the effects of (a) socioeconomic, residence, and spatial characteristics, (b) environmental awareness and behavior, and (c) factors related to consumer behavior, attitudes, and system attribute preferences. Factors affecting the installation of a microgeneration system are gender, age, income, residence type, ownership and size, environmental behavior, use of a subsidy program, as well as views on costs and market-related issues. When evaluating the effect of these factors over time, socioeconomic and residence characteristics, as well as environmental behavior, seem to have a fixed effect to the installation of residential microgeneration systems, with market acceptance fluctuations being related mainly to market conditions, including existing subsidy programs, expectations on fuel prices, and legislation.
Flexibility-Based Energy and Demand Management in Data Centers: A Case Study for Cloud Computing
Authors: Basmadjian Robert
Published: August 2019

The power demand (kW) and energy consumption (kWh) of data centers were augmented drastically due to the increased communication and computation needs of IT services. Leveraging demand and energy management within data centers is a necessity. Thanks to the automated ICT infrastructure empowered by the IoT technology, such types of management are becoming more feasible than ever. In this paper, we look at management from two different perspectives: (1) minimization of the overall energy consumption and (2) reduction of peak power demand during demand-response periods. Both perspectives have a positive impact on total cost of ownership for data centers. We exhaustively reviewed the potential mechanisms in data centers that provided flexibilities together with flexible contracts such as green service level and supply-demand agreements. We extended state-of-the-art by introducing the methodological building blocks and foundations of management systems for the above mentioned two perspectives. We validated our results by conducting experiments on a lab-grade scale cloud computing data center at the premises of HPE in Milano. The obtained results support the theoretical model, by highlighting the excellent potential of flexible service level agreements in Green IT: 33% of overall energy savings and 50% of power demand reduction during demand-response periods in the case of data center federation.
Adaptive Sliding Mode Trajectory Tracking Control for WMR Considering Skidding and Slipping via Extended State Observer
Authors: Wang Gang , Zhou Chenghui , Yu Yu , Liu Xiaoping
Published: August 2019

When the wheeled mobile robot (WMR) is required to perform specific tasks in complex environment, i.e., on the forestry, wet, icy ground or on the sharp corner, wheel skidding and slipping inevitably occur during trajectory tracking. To improve the trajectory tracking performance of WMR under unknown skidding and slipping condition, an adaptive sliding mode controller (ASMC) design approach based on the extended state observer (ESO) is presented. The skidding and slipping is regarded as external disturbance. In this paper, the ESO is introduced to estimate the lumped disturbance containing the unknown skidding and slipping, parameter variation, parameter uncertainties, etc. By designing a sliding surface based on the disturbance estimation, an adaptive sliding mode tracking control strategy is developed to attenuate the lumped disturbance. Simulation results show that higher precision tracking and better disturbance rejection of ESO-ASMC is realized for linear and circular trajectory than the ASMC scheme. Besides, experimental results indicate the ESO-ASMC scheme is feasible and effective. Therefore, ESO-ASMC scheme can enhance the energy efficiency for the differentially driven WMR under unknown skidding and slipping condition.
Analysis of Thermodynamic Models for Simulation and Optimisation of Organic Rankine Cycles
Authors: Durakovic Goran , Skaugen Geir
Published: August 2019

Equations of state (EOSs) form the base of every thermodynamic model used in the design of industrial processes, but little work has been done to evaluate these in the context of such models. This work evaluates 13 EOSs for their accuracy, computational time and robustness when used in an in-house optimisation program that finds the maximum power output of an organic Rankine cycle. The EOSs represent popular choices in the industry, such as the simple cubic EOSs, and more complex EOSs such as the ones based on corresponding state principles (CSP). These results were compared with results from using the Groupe Européen de Recherches Gazières (GERG) EOS, whose error is within experimental uncertainty. It appears that the corresponding state EOSs find a solution to the optimisation problem notably faster than GERG without significant loss of accuracy. A corresponding state method which used the Peng–Robinson EOS to calculate the shape factors and a highly accurate EOS for propane as the reference EOS, was shown to have a total deviation of just 0.6% as compared to GERG while also being 10 times as fast. The CSP implementation was also more robust, being able to converge successfully more often.
Using Machine Learning to Assess Site Suitability for Afforestation with Particular Species
Authors: Chen Yuling , Wu Baoguo , Chen Dong , Qi Yan
Published: August 2019

Judging and predicting tree suitability is of great significance in the cultivation and management of forests. Background and Objectives: Due to the diversity of tree species for afforestation in China and the lack of experts or the limitations of expert knowledge, the site rules of tree species in some regions are lacking or incomplete, so that a small number of tree suitability empirical site rules are difficult to adapt to the afforestation expert system’s diverse needs. Research Highlights: This paper explores an intelligent method to automatically extract rules for selecting favorable site conditions (tree suitability site rules) from a large amount of data to solve the problem of knowledge acquisition, updating and maintenance of suitable forest site rules in the expert system. Materials and Methods: Based on the method of site quality evaluation and the theory of the decision tree in knowledge discovery and machine learning, the dominant species of Chinese fir and Masson pine in the forest resources subcompartment data (FRSD) of Jinping County, Guizhou Province were taken as examples to select the important site factors affecting the forest quality and based on the site quality of potential productivity. Assessment methodology was proposed to determine the afforestation of a stand site by nonlinear quantile regression, the decision tree was constructed from the ID3, C5.0 and CART algorithms. Results: Finally, the best-performing CART algorithm was selected to construct the model, and the extractor of the afforestation rules was constructed. After validating the rules for selecting favorable site conditions of Chinese fir and Masson pine, the production representation method was used to construct the relationship model of the knowledge base. Conclusions: Intelligent extraction of suitable tree rules for afforestation design in an expert system was realized, which provided the theoretical basis and technical support for afforestation land planning and design.
Exploring the Use of a Modified High-Temperature, Short-Time Continuous Heat Exchanger with Extended Holding Time (HTST-EHT) for Thermal Inactivation of Trypsin Following Selective Enzymatic Hydrolysis of the β-Lactoglobulin Fraction in Whey Protein Isolate
Authors: Sáez Laura , Murphy Eoin , FitzGerald Richard J. , Kelly Phil
Published: August 2019

Tryptic hydrolysis of whey protein isolate under specific incubation conditions including a relatively high enzyme:substrate (E:S) ratio of 1:10 is known to preferentially hydrolyse β-lactoglobulin (β-LG), while retaining the other major whey protein fraction, i.e., α-lactalbumin (α-LA) mainly intact. An objective of the present work was to explore the effects of reducing E:S (1:10, 1:30, 1:50, 1:100) on the selective hydrolysis of β-LG by trypsin at pH 8.5 and 25 °C in a 5% (w/v) WPI solution during incubation periods ranging from 1 to 7 h. In addition, the use of a pilot-scale continuous high-temperature, short-time (HTST) heat exchanger with an extended holding time (EHT) of 5 min as a means of inactivating trypsin to terminate hydrolysis was compared with laboratory-based acidification to <pH 3 by the addition of HCl, and batch sample heating in a water bath at 85 °C. An E:S of 1:10 resulted in 100% and 30% of β-LG and α-LA hydrolysis, respectively, after 3 h, while an E:S reduction to 1:30 and 1:50 led >90% β-LG hydrolysis after respective incubation periods of 4 and 6 h, with <5% hydrolysis of α-LA in the case of 1:50. Continuous HTST-EHT treatment was shown to be an effective inactivation process allowing for the maintenance of substrate selectivity. However, HTST-EHT heating resulted in protein aggregation, which negatively impacts the downstream recovery of intact α-LA. An optimum E:S was determined to be 1:50, with an incubation time ranging from 3 h to 7 h leading to 90% β-LG hydrolysis and minimal degradation of α-LA. Alternative batch heating by means of a water bath to inactivate trypsin caused considerable digestion of α-LA, while acidification to <pH 3.0 restricted subsequent functional applications of the protein.
Testing Model of Purchase Intention for Fast Food in Mexico: How do Consumers React to Food Values, Positive Anticipated Emotions, Attitude toward the Brand, and Attitude toward Eating Hamburgers?
Authors: Pérez-Villarreal Héctor Hugo , Martínez-Ruiz María Pilar , Izquierdo-Yusta Alicia
Published: August 2019

This research investigated the effect of the food values, positive anticipated emotions, attitude toward the brand, and attitude toward eating a hamburger on purchase intention in fast-food restaurants in Mexico conjointly. The purpose of this study was to discover which variables influenced the consumer´s intention to buy. Data was collected from a survey of 512 Mexicans fast-food consumers. Structural equation modeling was used to test the hypothesized associations. The results showed that food values and positive anticipated emotions absolutely impact the attitude toward the brand, which impacts the purchase intention of the Mexican consumers. Nonetheless, the positive anticipated emotions impact stronger than food values, and the best way to get a purchase intention is toward the attitude of the brand rather than attitude toward eating a hamburger. The authors discussed inferences and suggestions for consumer approaches.
Analysis of Potential Risks Associated with Urban Stormwater Quality for Managed Aquifer Recharge
Authors: Song Yalin , Du Xinqiang , Ye Xueyan
Published: August 2019

Managed aquifer recharge (MAR) can be used to increase storage and availability of groundwater resources, but water resources available for recharge are constrained due to a surface water shortage. Alternative resources, like stormwater, are receiving increasing attention as sustainable resources for reuse in MAR. However, pollutants in stormwater can impact groundwater quality, and cause clogging of the infiltration system. Based on the stormwater data in the literature, the physicochemical stormwater properties of data were analyzed. The results showed that concentrations of pollutants from different underlying surfaces varied widely. The main pollutants of stormwater were as follows: Total suspended particles (TSSs), organic matter represented by the chemical oxygen demand (COD), nutrients (total nitrogen, TN; total phosphorus, TP; and NH3-N), and metals (Zn, Pb, Cu, Cd, Fe, and Mn). Based on the simulation of TOUGHREACT, the contamination risk of pollutants for each type of stormwater was assessed. The risk of contamination was divided into four categories due to the different migration times of ions through the sand column. The iron ion has the highest risk of contamination, followed by Zn and Mn, and the contamination risk of nutrients and other metals (Pb, Cu, and Cd) are relatively low. Besides, the physical, biological, and chemical clogging risk were evaluated. The physical clogging potential of all types of stormwater is very high because of the high concentration of TSS. According to the concentration of TN that can spur the growth of bacteria and algae, the relative risk of biological clogging for stormwater is greenbelt stormwater < road stormwater < roof stormwater. However, only road stormwater has high chemical clogging due to the existence of iron, which can generate precipitation that blocks the pore volume.
Leading Progress in Digital Terrain Analysis and Modeling
Authors: Sofia Giulia , Eltner Anette , Nikolopoulos Efthymios , Crosby Christopher
Published: August 2019

Digital Terrain analysis (DTA) and modeling has been a flourishing interdisciplinary field for decades, with applications in hydrology, geomorphology, soil science, engineering projects and computer sciences. Currently, DTA is characterized by a proliferation of multispectral data from new sensors and platforms, driven by regional and national governments, commercial businesses, and scientific groups, with a general trend towards data with higher spatial, spectral or temporal resolutions. Deriving meaningful and interpretable products from such a large pool of data sources sets new challenges. The articles included in this special issue (SI) focuses on terrain analysis applications that advance the fields of hydrology, geomorphology, soil science, geographic information software (GIS), and computer science. They showcase challenging examples of DTA tackling different subjects or different point of views on the same subject.
A PDF Tile Model for Geographic Map Data
Authors: Zhou Xiaodong , Ai Tinghua , Meng Nina , Xie Peng
Published: August 2019

Vector tile mapping is an important issue in web map research. At present, vector tile mapping requires the symbolization of geographic information, as supported by cartographic software, and the development of a corresponding symbolic database when web map services are provided for users. The development of PDF (portable document format) mapping makes it possible to use symbolized map data directly for web map services. This paper presents a PDF tile map model suitable for web map services, in order to provide a new solution for vector tile mapping. This paper details the construction and establishment method of the PDF tile map model and verifies that the model has the characteristics of a vector tile map and that this approach can provide web map services. In addition, this model has some other noticeable characteristics. First, the map service supported by this model does not require the support of cartographic software, and thus has low system software and hardware requirements. Second, the maps displayed in the service system can be directly used for high-quality map publishing. Third, the high popularity of the PDF format can promote the sharing of PDF tile maps and reduce the use threshold of ordinary users.
Road Network Extraction from Low-Frequency Trajectories Based on a Road Structure-Aware Filter
Authors: Li Daigang , Li Junhan , Li Juntao
Published: August 2019

Many studies have utilized global navigation satellite system (such as global positioning system (GPS)) trajectories in order to successfully infer road networks because such data can reveal the geometry and development of a road network, can be obtained in a timely manner, and updated on a low budget. Unfortunately, existing studies for inferring road networks from vehicle traces suffer from low accuracy, especially in dense urban regions and locations with complex structures, such as roundabouts, overpasses, and complex intersections. This study presents a novel two-stage approach for inferring road networks from trajectory points and capturing road geometry with better accuracy. First, a lane structure-aware filter is proposed to cluster vehicle trajectories influenced by high noise and outliers in order to reveal the continuous structure points of lane curves from massive trajectory points. Second, a road tracing operator is utilized to segment the road network geometry by inserting new vertices and segments to a vigorous vertex in the heading of the structure points that are extracted in the first step. Experimental results demonstrate the increased accuracy of the extracted roads and show that the proposed method exhibits strong robustness to noise and various sampling rates.
Development of Multi-Target Chemometric Models for the Inhibition of Class I PI3K Enzyme Isoforms: A Case Study Using QSAR-Co Tool
Authors: Halder Amit Kumar , Cordeiro M. Natália Dias Soeiro
Published: August 2019

The present work aims at establishing multi-target chemometric models using the recently launched quantitative structure–activity relationship (QSAR)-Co tool for predicting the activity of inhibitor compounds against different isoforms of phosphoinositide 3-kinase (PI3K) under various experimental conditions. The inhibitors of class I phosphoinositide 3-kinase (PI3K) isoforms have emerged as potential therapeutic agents for the treatment of various disorders, especially cancer. The cell-based enzyme inhibition assay results of PI3K inhibitors were curated from the CHEMBL database. Factors such as the nature and mutation of cell lines that may significantly alter the assay outcomes were considered as important experimental elements for mt-QSAR model development. The models, in turn, were developed using two machine learning techniques as implemented in QSAR-Co: linear discriminant analysis (LDA) and random forest (RF). Both techniques led to models with high accuracy (ca. 90%). Several molecular fragments were extracted from the current dataset, and their quantitative contributions to the inhibitory activity against all the proteins and experimental conditions under study were calculated. This case study also demonstrates the utility of QSAR-Co tool in solving multi-factorial and complex chemometric problems. Additionally, the combination of different in silico methods employed in this work can serve as a valuable guideline to speed up early discovery of PI3K inhibitors.
Magnetorheological Hybrid Elastomers Based on Silicone Rubber and Magnetorheological Suspensions with Graphene Nanoparticles: Effects of the Magnetic Field on the Relative Dielectric Permittivity and Electric Conductivity
Authors: Bica Ioan , Bunoiu Octavian Mădălin
Published: August 2019

Hybrid magnetorheological elastomers (hMREs) were manufactured based on silicone rubber, silicone oil, carbonyl iron microparticles, graphene nanoparticles and cotton fabric. Using the hMREs, flat capacitors (FCs) were made. Using the installation described in this paper, the electrical capacitance and the coefficient of dielectric losses of the hMREs were measured as a function of the intensity of the magnetic field superimposed over an alternating electric field. From the data obtained, the electrical conductivity, the relative dielectric permittivity and magnetodielectric effects are determined. It is observed that the obtained quantities are significantly influenced by the intensity of the magnetic field and the amount of graphene used.
Physiologically Relevant Oxygen Concentration (6% O2) as an Important Component of the Microenvironment Impacting Melanoma Phenotype and Melanoma Response to Targeted Therapeutics In Vitro
Authors: Osrodek Marta , Hartman Mariusz , Czyz Malgorzata
Published: August 2019

Cancer cell phenotype largely depends on oxygen availability. The atmospheric oxygen concentration (21%) used in in vitro studies is much higher than in any human tissue. Using well-characterized patient-derived melanoma cell lines, we compared: (i) activities of several signaling pathways, and (ii) the effects of vemurafenib and trametinib in hyperoxia (21% O2), normoxia (6% O2) and hypoxia (1% O2). A high plasticity of melanoma cells in response to changes in oxygen supplementation and drug treatment was observed, and the transcriptional reprograming and phenotypic changes varied between cell lines. Normoxia enhanced the expression of vascular endothelial growth factor (VEGF), glucose metabolism/transport-related genes, and changed percentages of NGFR- and MITF-positive cells in cell line-dependent manner. Increased protein stability might be responsible for high PGC1α level in MITFlow melanoma cells. Vemurafenib and trametinib while targeting the activity of MAPK/ERK pathway irrespective of oxygen concentration, were less effective in normoxia than hyperoxia in reducing levels of VEGF, PGC1α, SLC7A11 and Ki-67-positive cells in cell line-dependent manner. In conclusion, in vitro studies performed in atmospheric oxygen concentration provide different information on melanoma cell phenotype and response to drugs than performed in normoxia, which might partially explain the discrepancies between results obtained in vitro and in clinical settings.
Altered White Matter Integrity after Mild to Moderate Traumatic Brain Injury
Authors: Kim Eunkyung , Seo Han Gil , Lee Hyun Haeng , Lee Seung Hak , Choi Seung Hong , Yoo Roh-Eul , Cho Won-Sang , Wagner Amy K. , Oh Byung-Mo
Published: August 2019

(1) Background: White matter changes among individuals with mild-to-moderate traumatic brain injury (TBI) may be sensitive imaging markers reflecting functional impairment, particularly in the context of post-concussion syndrome. The objective of this study was to examine the altered white matter integrity in mild-to-moderate TBI patients compared with age-matched normal controls. (2) Methods: Diffusion tensor imaging data from 15 individuals with TBI and 15 control subjects were retrospectively obtained. We investigated and compared white matter integrity in both groups, with regard to fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) and examined the relationship with cognitive dysfunction and impaired balance in patients. (3) Results: In comparison with controls, the TBI patients had significantly decreased FA as well as increased RD, in the right corticospinal tract. Decreased RD was observed in the left cerebellar area near the middle cerebellar peduncle. Decreased AD was observed in the left inferior cerebellar peduncle, showing positive correlation with poor balance control. We observed decreased FA and increased AD in the left superior longitudinal fasciculus showing positive and negative correlation, respectively, with cognitive function in the TBI group. (4) Conclusions: Altered white matter integrity in mild-to-moderate TBI cases may be indicative of cognitive dysfunction and impaired balance.
Received Signal Strength Indication (RSSI) of 2.4 GHz and 5 GHz Wireless Local Area Network Systems Projected over Land and Sea for Near-Shore Maritime Robot Operations
Authors: Yamamoto Brennan , Wong Allison , Agcanas Peter Joseph , Jones Kai , Gaspar Dominic , Andrade Raymond , Trimble A Zachary
Published: August 2019

The effect of the maritime environment on radio frequency (RF) propagation is not well understood. In this work, we study the propagation of ad hoc 2.4 GHz and 5 GHz wireless local area network systems typically used for near-shore operation of unmanned surface vehicles. In previous work, maritime RF propagation performance is evaluated by collecting RSSI data over water and comparing it against existing propagation models. However, the multivariate effect of the maritime environment on RF propagation means that these single-domain studies cannot distinguish between factors unique to the maritime environment and factors that exist in typical terrestrial RF systems. In this work, we isolate the effect of the maritime environment by collecting RSSI data over land and over seawater at two different frequencies and two different ground station antenna heights with the same physical system in essentially the same location. Results show that our 2.4 GHz, 2 m antenna height system received a 2 to 3 dBm path loss when transitioning from over-land to over-seawater (equivalent to a 25 to 40% reduction in range); but increasing the frequency and antenna height to 5 GHz, 5 m respectively resulted in no meaningful path loss under the same conditions; this reduction in path loss by varying frequency and antenna height has not been demonstrated in previous work. In addition, we studied the change in ground reflectivity coefficient, R , when transitioning from over-land to over-seawater. Results show that R remained relatively constant, −0.49 ≤ R ≤ −0.45, for all of the over-land experiments; however, R demonstrated a frequency dependence during the over-seawater experiments, ranging from −0.39 ≤ R ≤ −0.33 at 2.4 GHz, and −0.51 ≤ R ≤ −0.50 at 5 GHz.
Reproducibility of Gaseous Phase Area on Journal Bearing Utilizing Multi-Phase Flow CFD Analysis under Flooded and Starved Lubrication Conditions
Authors: Ochiai Masayuki , Sakai Fuma , Hashimoto Hiromu
Published: August 2019

It is important to predict the gaseous phase area of journal bearing. However, a detailed calculation method for such gaseous phase areas has not yet been proposed. In this study, the gaseous-phase areas in small bore journal bearings under flooded and starved lubrication conditions are analyzed in terms of the computational fluid dynamics (CFD) of two-phase flow while using a volume of fluid (VOF) method. Furthermore, the influence of surface tension and vapor pressure conditions were investigated, and the analytical and experimental results were compared. The analytical results of VOF for vapor pressure and surface tension were observed to be consistent with the experimental observations under both flooded and starved lubrication conditions. Furthermore, under starved lubrication condition, the analytical results agree well with the observed results for the interface of the oil film and cavitation upon the rupture of the oil film. While using these results, CFD analysis of the two-phase flow of the VOF can be conducted in terms of vapor pressure and surface tension to estimate the gaseous-phase areas of journal bearings under flooded and starved lubrication conditions.
Calcined Post-Production Waste as Materials Suitable for the Hydrothermal Synthesis of Zeolites
Authors: Łach Michał , Grela Agnieszka , Komar Norbert , Mikuła Janusz , Hebda Marek
Published: August 2019

The zeolite production process is currently being very intensively researched. Due to environmental protection, as well as issues related to the guidelines of a zero-waste economy, all activities aimed at obtaining such materials from post-processed waste are extremely important. This article presents an innovative method of utilising calcined carboniferous shale in order to produce synthetic zeolites. The raw material for testing came from two Polish hard coal mines. Both the chemical and phase composition of the coal shale were characterised. Based on the recorded thermal analysis results coupled with the mass spectrometer, the processes occurring during the heating of raw materials were interpreted and the calcination temperatures were determined. The changes in the phase composition of raw materials resulting from the calcination process used were also analysed. The heat-treated raw materials were subjected to the synthesis of zeolites in an aqueous solution of sodium hydroxide by means of the hydrothermal method at a concentration of 2.75 M. The results of water leaching and structural parameters are presented for both raw materials, as well as the produced synthesis. The conducted research confirmed that after the application of the synthetic process on coal shale, a zeolite with a surface area of SBET equal to 172 m2/g can be obtained.
Optimized Dental Implant Fixture Design for the Desirable Stress Distribution in the Surrounding Bone Region: A Biomechanical Analysis
Authors: Kim Won Hyeon , Lee Jae-Chang , Lim Dohyung , Heo Young-Ku , Song Eun-Sung , Lim Young-Jun , Kim Bongju
Published: August 2019

The initial stability of a dental implant is known to be an indicator of osseointegration at immediate loading upon insertion. Implant designs have a fundamental role in the initial stability. Although new designs with advanced surface technology have been suggested for the initial stability of implant systems, verification is not simple because of various assessment factors. Our study focused on comparing the initial stability between two different implant systems via design aspects. A simulated model corresponding to the first molar derived from the mandibular bone was constructed. Biomechanical characteristics between the two models were compared by finite element analysis (FEA). Mechanical testing was also performed to derive the maximum loads for the two implant systems. CMI IS-III active (IS-III) had a more desirable stress distribution than CMI IS-II active (IS-II) in the surrounding bone region. Moreover, IS-III decreased the stress transfer to the nerve under the axial loading direction more than IS-II. Changes of implant design did not affect the maximum load. Our analyses suggest that the optimized design (IS-III), which has a bigger bone volume without loss of initial fixation, may minimize the bone damage during fixture insertion and we expect greater effectiveness in older patients.
Applications of Plasma-Liquid Systems: A Review
Authors: Rezaei Fatemeh , Vanraes Patrick , Nikiforov Anton , Morent Rino , De Geyter Nathalie
Published: August 2019

Plasma-liquid systems have attracted increasing attention in recent years, owing to their high potential in material processing and nanoscience, environmental remediation, sterilization, biomedicine, and food applications. Due to the multidisciplinary character of this scientific field and due to its broad range of established and promising applications, an updated overview is required, addressing the various applications of plasma-liquid systems till now. In the present review, after a brief historical introduction on this important research field, the authors aimed to bring together a wide range of applications of plasma-liquid systems, including nanomaterial processing, water analytical chemistry, water purification, plasma sterilization, plasma medicine, food preservation and agricultural processing, power transformers for high voltage switching, and polymer solution treatment. Although the general understanding of plasma-liquid interactions and their applications has grown significantly in recent decades, it is aimed here to give an updated overview on the possible applications of plasma-liquid systems. This review can be used as a guide for researchers from different fields to gain insight in the history and state-of-the-art of plasma-liquid interactions and to obtain an overview on the acquired knowledge in this field up to now.
A New Hybrid CQ Algorithm for the Split Feasibility Problem in Hilbert Spaces and Its Applications to Compressed Sensing
Authors: Suantai Suthep , Kesornprom Suparat , Cholamjiak Prasit
Published: August 2019

In this paper, we focus on studying the split feasibility problem (SFP), which has many applications in signal processing and image reconstruction. A popular technique is to employ the iterative method which is so called the relaxed CQ algorithm. However, the speed of convergence usually depends on the way of selecting the step size of such algorithms. We aim to suggest a new hybrid CQ algorithm for the SFP by using the self adaptive and the line-search techniques. There is no computation on the inverse and the spectral radius of a matrix. We then prove the weak convergence theorem under mild conditions. Numerical experiments are included to illustrate its performance in compressed sensing. Some comparisons are also given to show the efficiency with other CQ methods in the literature.
Theoretical Evaluation of Graphene Membrane Performance for Hydrogen Separation Using Molecular Dynamic Simulation
Authors: Nouri Mahdi , Ghasemzadeh Kamran , Iulianelli Adolfo
Published: August 2019

The main purposes of this study are to evaluate the performance of graphene membranes in the separation/purification of hydrogen from nitrogen from a theoretical point of view using the molecular dynamic (MD) simulation method, and to present details about molecular mechanisms of selective gas diffusion through nanoscale pores of graphene membranes at the simulated set conditions. On the other hand, permeance and perm-selectivity are two significant parameters of such a membrane that can be controlled by several variables such as pressure gradient, pore density, pore layer angles etc. Hence, in this work, the hydrogen and nitrogen permeating fluxes as well as the H2/N2 ideal perm-selectivity are investigated from a theoretical point of view in a two-layer nanoporous graphene (NPG) membrane through classical MD simulations, wherein the effects of pressure gradient, pore density, and pore angle on the NPG membrane performance are evaluated and discussed. Simulation outcomes suggest that hydrogen and nitrogen permeating fluxes increase as a consequence of an increment of pressure gradient across the membrane and pore density.
Hypoglycemic, Antiglycation, and Cytoprotective Properties of a Phenol-Rich Extract From Waste Peel of Punica granatum L. var. Dente di Cavallo DC2
Authors: Di Sotto Antonella , Locatelli Marcello , Macone Alberto , Toniolo Chiara , Cesa Stefania , Carradori Simone , Eufemi Margherita , Mazzanti Gabriela , Di Giacomo Silvia
Published: August 2019

Pomegranate peel is a natural source of phenolics, claimed to possess healing properties, among which are antioxidant and antidiabetic. In the present study, an ethyl acetate extract, obtained by Soxhlet from the peel of Dente di Cavallo DC2 pomegranate (PGE) and characterized to contain 4% w/w of ellagic acid, has been evaluated for its hypoglycemic, antiglycation, and antioxidative cytoprotective properties, in order to provide possible evidence for future nutraceutical applications. The α-amylase and α-glucosidase enzyme inhibition, interference with advanced glycation end-products (AGE) formation, and metal chelating abilities were studied. Moreover, the possible antioxidant cytoprotective properties of PGE under hyperglycemic conditions were assayed. Phenolic profile of the extract was characterized by integrated chromatographic and spectrophotometric methods. PGE resulted able to strongly inhibit the tested enzymes, especially α-glucosidase, and exerted chelating and antiglycation properties. Also, it counteracted the intracellular oxidative stress under hyperglycemic conditions, by reducing the levels of reactive oxygen species and total glutathione. Among the identified phenolics, rutin was the most abundant flavonoid (about 4 % w/w). Present results suggest PGE to be a possible remedy for hyperglycemia management and encourage further studies to exploit its promising properties.
Characterization and Evaluation of Aroma Quality in Doubanjiang, a Chinese Traditional Fermented Red Pepper Paste, Using Aroma Extract Dilution Analysis and a Sensory Profile
Authors: Li Zhihua , Dong Ling , Jeon Jin , Kwon So Young , Zhao Chi , Baek Hyung-Hee
Published: August 2019

Doubanjiang, a Chinese traditional fermented red pepper paste, is eaten worldwide for its unique flavor. The objective of this study was to evaluate the aroma quality of doubanjiang using solvent-assisted flavor evaporation (SAFE) and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). A total of 165 volatile compounds, belonging to 13 chemical classes, were identified. Esters and hydrocarbons were the predominant groups. Thirteen aroma-active compounds were detected by AEDA of SAFE and HS-SPME, and their odor activity values (OAVs) were calculated by dividing their concentration by their odor threshold in water. Among them, ethyl isovalerate, β-damascenone, 3-isobutyl-2-methoxypyrazine (IBMP), and sotolone had the highest OAVs (>1000). In addition, sotolone, methional, β-damascenone, 3-isobutyl-2-methoxypyrazine, ethyl isovalerate, phenylethyl alcohol and linalool had high flavor dilution (FD) factors. Sotolone, β-damascenone and 3-isobutyl-2-methoxypyrazine were identified for the first time in doubanjiang and played significant roles in its aroma quality.
Obtaining an Extract Rich in Phenolic Compounds from Olive Pomace by Pressurized Liquid Extraction
Authors: Cea Pavez Inés , Lozano-Sánchez Jesús , Borrás-Linares Isabel , Nuñez Hugo , Robert Paz , Segura-Carretero Antonio
Published: August 2019

The olive oil industry produces large volumes of wastes, which are also potential sources of bioactive compounds by developing healthy and/or functional foods. Extraction of phenolic compounds from the residues of the olive oil is mainly carried out with solvents. However, there is currently a growing public awareness about the use of organic solvents in food processing, which has pointed out the need for the application of clean technologies such as pressurized liquid extraction (PLE). Therefore, the aim of this research was to optimize the phenolic compound extraction from olive pomace by PLE, establishing the qualitative and quantitative phenolic profile by HPLC-ESI-TOF/MS. The extraction design to recover phenolics from olive pomace demonstrates a great compositional variability of PLE extracts obtained under different experimental conditions. Indeed, quantitative results have pointed out the selectivity of PLE extraction when this technique is applied to the treatment of olive pomace. PLE-optimized conditions showed higher total phenolic compound content than conventional extraction (1659 mg/kg d.w. and 281.7 mg/kg d.w., respectively). Among these phenolics, the quantity of secoiridoids and flavonoids in the optimized PLE extract was three and four times higher than in conventional extracts. Furthermore, optimal PLE conditions allowed to obtain an enriched hydroxytyrosol extract which was not detected in the conventional one.
Kurarinone from Sophora Flavescens Roots Triggers ATF4 Activation and Cytostatic Effects Through PERK Phosphorylation
Authors: Nishikawa Sakiko , Itoh Yuka , Tokugawa Muneshige , Inoue Yasumichi , Nakashima Ken-ichi , Hori Yuka , Miyajima Chiharu , Yoshida Kou , Morishita Daisuke , Ohoka Nobumichi , Inoue Makoto , Mizukami Hajime , Makino Toshiaki , Hayashi Hidetoshi
Published: August 2019

In response to cellular stresses, activating transcriptional factor 4 (ATF4) regulates the expression of both stress-relieving genes and apoptosis-inducing genes, eliciting cell fate determination. Since pharmacological activation of ATF4 exerts potent anti-tumor effects, modulators of ATF4 activation may have potential in cancer therapy. We herein attempted to identify small molecules that activate ATF4. A cell-based screening to monitor TRB3 promoter activation was performed using crude drugs used in traditional Japanese Kampo medicine. We found that an extract from Sophora flavescens roots exhibited potent TRB3 promoter activation. The activity-guided fractionation revealed that kurarinone was identified as the active ingredient. Intriguingly, ATF4 activation in response to kurarinone required PKR-like endoplasmic reticulum kinase (PERK). Moreover, kurarinone induced the cyclin-dependent kinase inhibitor p21 as well as cytostasis in cancer cells. Importantly, the cytostatic effect of kurarinone was reduced by pharmacological inhibition of PERK. These results indicate that kurarinone triggers ATF4 activation through PERK and exerts cytostatic effects on cancer cells. Taken together, our results suggest that modulation of the PERK-ATF4 pathway with kurarinone has potential as a cancer treatment.
Identification of Constituents Affecting the Secretion of Pro-Inflammatory Cytokines in LPS-Induced U937 Cells by UHPLC-HRMS-Based Metabolic Profiling of the Traditional Chinese Medicine Formulation Huangqi Jianzhong Tang
Authors: Nöst Xuehong , Pferschy-Wenzig Eva-Maria , Nikles Stefanie , He Xiaojuan , Fan Danping , Lu Aiping , Yuk Jimmy , Yu Kate , Isaac Giorgis , Bauer Rudolf
Published: August 2019

Within non-communicable diseases, chronic inflammatory conditions represent one of the biggest challenges for modern medicine. Traditional Chinese Medicine (TCM) has been practiced over centuries and has accumulated tremendous empirical knowledge on the treatment of such diseases. Huangqi Jianzhong Tang (HQJZT) is a famous TCM herbal formula composed of Radix Astragali, Ramulus Cinnamomi, Radix et Rhizoma Glycyrrhizae Praeparata cum Melle, Radix Paeoniae Alba, Rhizoma Zingiberis Recens, Fructus Jujubae and Saccharum Granorum (maltose), which has been used for the treatment of various chronic inflammatory gastrointestinal diseases. However, there is insufficient knowledge about its active constituents and the mechanisms responsible for its effects. The present study aimed at identifying constituents contributing to the bioactivity of HQJZT by combining in vitro cytokine production assays and LC-MS metabolomics techniques. From the HQJZT decoction as well as from its single herbal components, extracts of different polarities were prepared. Phytochemical composition of the extracts was analyzed by means of UPLC-QTOF-MS/MS. The inhibitory effects of the extracts on TNF-α, IL-1β and IFN-γ production were studied in U937 cells. Phytochemical and pharmacological bioactivity data were correlated by orthogonal projection to latent structures discriminant analysis (OPLS-DA) in order to identify those HQJZT constituents which may be relevant for the observed pharmacological activities. The investigations resulted in the identification of 16 HQJZT constituents, which are likely to contribute to the activities observed in U937 cells. Seven of them, namely calycosin, formononetin, astragaloside I, liquiritigenin, 18β-glycyrrhetinic acid, paeoniflorin and albiflorin were unambiguously identified. The predicted results were verified by testing these compounds in the same pharmacological assays as for the extracts. In conclusion, the anti-inflammatory activity of HQJZT could be substantiated by in vitro pharmacological screening, and the predicted activities of the OPLS-DA hits could be partially verified. Moreover, the benefits and limitations of MVDA for prediction pharmacologically active compounds contributing to the activity of a TCM mixture could be detected.
Improved Dermal Delivery of Cyclosporine A Loaded in Solid Lipid Nanoparticles
Authors: Essaghraoui Abderrazzaq , Belfkira Ahmed , Hamdaoui Bassou , Nunes Cláudia , Lima Sofia A. Costa , Reis Salette
Published: August 2019

Cyclosporine A (CsA) is an immunosuppressant frequently used in the therapy of autoimmune disorders, including skin-related diseases. Aiming towards topical delivery, CsA was successfully incorporated into lipid nanoparticles of Lipocire DM and Pluronic F-127 using the hot homogenization method. Two different nanocarriers were optimized: solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) where oleic acid was the liquid lipid. The developed nanoparticles showed mean sizes around 200 nm, a negative surface charge, and drug entrapment efficiencies around 85% and 70% for SLNs and NLCs, respectively. The spherical CsA-loaded lipid nanoparticles were stable for 9 weeks when stored at room temperature, and exhibited in vitro pH-dependent release under skin mimetic conditions, following the Peppas–Korsmeyer model. CsA, when loaded in SLNs, was safe to be used up to 140 μg mL−1 in fibroblasts and keratinocytes, while CsA-loaded NLCs and free drug exhibited IC50 values of 55 and 95 μg mL−1 (fibroblasts) and 28 and 30 μg mL−1 (keratinocytes), respectively. The developed SLNs were able to retain the drug in pork skin with a reduced permeation rate in relation to NLCs. These findings suggest that SLNs are a potential alternative to produce stable and safe CsA nanocarriers for topical administration.
Reduction in Toxicity of Nano-Ag-Polyvinyl-pyrrolidone Using Hydra Proteins and Peptides during Zebrafish Embryogenesis
Authors: Kim Soon Seok , Lee Jin Ah , Yeo Min-Kyeong
Published: August 2019

Hydra magnipapillata cells reduce the toxicity of silver nanomaterials to zebrafish (Danio rerio) embryos. In this study, we investigated whether Hydra protein (HP) and Hydra basal disc peptide (Hym176) materials reduce nano-Ag-polyvinylpyrrolidone (N-Ag-PVP) toxicity during embryogenesis of the nanosensitive organism zebrafish. Protein (HP) was extracted from Hydra, and peptide (Hym176) was extracted from the hydra basal disc, which is attractive to nanomaterials and related to the immune system. The experimental conditions were exposure to N-Ag-PVP, HP, N-Ag-PVP+HP, Hym176, or N-Ag-PVP+Hym176 during embryo development. N-Ag-PVP+HP group showed lower toxicity than N-Ag-PVP group. In addition, in the N-Ag-PVP+HP group formed aggregated nanomaterials (≥200 nm size) through electrostatic bonding. In the gene expression profile, HP group differed in gene expression profile compared the other experimental groups and it was no genetic toxicity. HP showed a tendency to reduce side effects and abnormal gene expression produced by N-Ag-PVP with no evidence of inherent toxicity. Considering the potential nanotoxicity effects of released nanomaterials on the ecosystem, the reduction of nanotoxicity observed with HP natural materials should be regarded with great interest in terms of the overall health of the ecosystem.
Whole Transcriptome Analysis of Aedes albopictus Mosquito Head and Thorax Post-Chikungunya Virus Infection
Authors: Vedururu Ravi kiran , Neave Matthew J. , Sundaramoorthy Vinod , Green Diane , Harper Jennifer A. , Gorry Paul R. , Duchemin Jean-Bernard , Paradkar Prasad N.
Published: August 2019

Chikungunya virus (CHIKV) is transmitted by Aedes mosquitoes and causes prolonged arthralgia in patients. After crossing the mosquito midgut barrier, the virus disseminates to tissues including the head and salivary glands. To better understand the interaction between Aedes albopictus and CHIKV, we performed RNASeq analysis on pools of mosquito heads and parts of the thorax 8 days post infection, which identified 159 differentially expressed transcripts in infected mosquitos compared to uninfected controls. After validation using RT-qPCR (reverse transcriptase-quantitative polymerase chain reaction), inhibitor of Bruton’s tyrosine kinase (BTKi), which has previously been shown to be anti-inflammatory in mammals after viral infection, was further evaluated for its functional significance. Knockdown of BTKi using double-stranded RNA in a mosquito cell line showed no significant difference in viral RNA or infectivity titer. However, BTKi gene knocked-down cells showed increased apoptosis 24 hours post-infection compared with control cells, suggesting involvement of BTKi in the mosquito response to viral infection. Since BTK in mammals promotes an inflammatory response and has been shown to be involved in osteoclastogenesis, a hallmark of CHIKV pathogenesis, our results suggest a possible conserved mechanism at play between mosquitoes and mammals. Taken together, these results will add to our understanding of Aedes Albopictus interactions with CHIKV.