bluuebunny/crossref_metadata_2025 huggingface dataset:
Liquid-Crystal and Fire-Retardant Properties of New Hexasubstituted Cyclotriphosphazene Compounds with Two Schiff Base Linking Units
Authors: Jamain Zuhair , Khairuddean Melati , Guan-Seng Tay
Published: May 2020

A series of new hexasubstituted cyclotriphosphazene compounds (4a–j) consisting of two Schiff base linking units and different terminal substituents was successfully synthesized and characterized. The structures of these compounds were confirmed using Fourier Transform Infra-Red (FTIR), Nuclear Magnetic Resonance (NMR), and CHN elemental analysis. Polarized optical microscopy (POM) was used to determine their liquid-crystal behavior, which was then further confirmed using differential scanning calorimetry (DSC). Compounds 4a–i with heptyl, nonyl, decyl, dodecyl, tetradecyl, hydroxy, 4-carboxyphenyl, chloro, and nitro terminal ends, respectively, showed the liquid-crystal properties, whereas compound 4j with the amino group was found to be non-mesogenic. The attachment of an electron-donating group in 4j eventually give a non-mesogenic product. The study of the fire-retardant properties of these compounds was done using the limiting oxygen index (LOI). In this study, polyester resin (PE) was used as a matrix for moulding, and the LOI value of pure PE was 22.53%. The LOI value increased to 24.71% when PE was incorporated with 1 wt.% of hexachlorocyclotriphosphazene (HCCP), thus indicating that HCCP has a good fire-retardant properties. The result showed that all the compounds have good agreement in their LOI values. Compound 4i with a nitro terminal group gave the highest LOI value of 28.37%.
Sunscreen-Assisted Selective Photochemical Transformations
Authors: Eivgi Or , Lemcoff N. Gabriel
Published: May 2020

In this review, we describe a simple and general procedure to accomplish selective photochemical reaction sequences for two chromophores that are responsive to similar light frequencies. The essence of the method is based on the exploitation of differences in the molar absorptivity at certain wavelengths of the photosensitive groups, which is enhanced by utilizing light-absorbing auxiliary filter molecules, or “sunscreens”. Thus, the filter molecule hinders the reaction pathway of the least absorbing molecule or group, allowing for the selective reaction of the other. The method was applied to various photochemical reactions, from photolabile protecting group removal to catalytic photoinduced olefin metathesis in different wavelengths and using different sunscreen molecules. Additionally, the sunscreens were shown to be effective also when applied externally to the reaction mixture, avoiding any potential chemical interactions between sunscreen and substrates and circumventing the need to remove the light-filtering molecules from the reaction mixture, adding to the simplicity and generality of the method.
The Nutraceutical Value of Carnitine and Its Use in Dietary Supplements
Authors: Durazzo Alessandra , Lucarini Massimo , Nazhand Amirhossein , Souto Selma B. , Silva Amélia M. , Severino Patrícia , Souto Eliana B. , Santini Antonello
Published: May 2020

Carnitine can be considered a conditionally essential nutrient for its importance in human physiology. This paper provides an updated picture of the main features of carnitine outlining its interest and possible use. Particular attention has been addressed to its beneficial properties, exploiting carnitine’s properties and possible use by considering the main in vitro, in animal, and human studies. Moreover, the main aspects of carnitine-based dietary supplements have been indicated and defined with reference to their possible beneficial health properties.
Bar Adsorptive Microextraction Coated with Carbon-Based Phase Mixtures for Performance-Enhancement to Monitor Selected Benzotriazoles, Benzothiazoles, and Benzenesulfonamides in Environmental Water Matrices
Authors: Ahmad Samir M. , Calado Bruno B.C. , Oliveira Mariana N. , Neng Nuno R. , Nogueira J.M.F.
Published: May 2020

In the present work we propose, for the first time, bar adsorptive microextraction coated with carbon-based phase mixtures, followed by microliquid desorption and high performance liquid chromatography-diode array detection (BAμE-μLD/HPLC-DAD) analysis, to enhance the performance of the determination of traces of benzotriazoles (BTRs), benzothiazoles (BTs), and benzenesulfonamide derivatives (BSDs) in environmental water matrices. Assessing six carbon-based sorbents (CA1, CN1, B test EUR, SX PLUS, SX 1, and R) with different selectivity properties allowed us to tailor the best phase mixture (R, 12.5%/CN1, 87.5%) that has convenient porosity, texture, and surface chemistry (pHPZC,mix ~6.5) for trace analysis of benzenesulfonamide, 1-hydroxybenzotriazole, 1H-benzotriazole, 5-methyl-1H-benzotriazole, benzothiazole, and 1,3-benzothiazol-2-ol chemicals in aqueous media. Optimized experimental conditions provided average recoveries ranging from 37.9% to 59.2%, appropriate linear dynamic ranges (5.0 to 120.0 µg L−1; r2 ≥ 0.9964), limits of detection between 1.0 and 1.4 μg L−1, and good precisions (relative standard deviation (RSD) ≤ 9.3%). The proposed methodology (BAμE(R, 12.5%/CN1, 87.5%)-μLD/HPLC-DAD) also proved to be a suitable sorption-based static microextraction alternative to monitor traces of BTRs, BTs, and BSDs in rain, waste, tap, and estuarine water samples. From the data obtained, the proposed approach showed that the BAμE technique with the addition of lab-made devices allows users to adapt the technique to use sorbents or mixtures of sorbents with the best selectivity characteristics whenever distinct classes of target analytes occur simultaneously in the same application.
Polysaccharide κ-Carrageenan as Doping Agent in Conductive Coatings for Electrochemical Controlled Release of Dexamethasone at Therapeutic Doses
Authors: Ramírez Sánchez Karla , Ledezma-Espinoza Aura , Sánchez-Kopper Andrés , Avendaño-Soto Esteban , Prado Mónica , Starbird Perez Ricardo
Published: May 2020

Smart conductive materials are developed in regenerative medicine to promote a controlled release profile of charged bioactive agents in the vicinity of implants. The incorporation and the active electrochemical release of the charged compounds into the organic conductive coating is achieved due to its intrinsic electrical properties. The anti-inflammatory drug dexamethasone was added during the polymerization, and its subsequent release at therapeutic doses was reached by electrical stimulation. In this work, a Poly (3,4-ethylenedioxythiophene): κ-carrageenan: dexamethasone film was prepared, and κ-carrageenan was incorporated to keep the electrochemical and physical stability of the electroactive matrix. The presence of κ-carrageenan and dexamethasone in the conductive film was confirmed by µ-Raman spectroscopy and their effect in the topographic was studied using profilometry. The dexamethasone release process was evaluated by cyclic voltammetry and High-Resolution mass spectrometry. In conclusion, κ-carrageenan as a doping agent improves the electrical properties of the conductive layer allowing the release of dexamethasone at therapeutic levels by electrochemical stimulation, providing a stable system to be used in organic bioelectronics systems.
Comparative Analysis of Milk Fat Globular Membrane (MFGM) Proteome between Saudi Arabia Camelus dromedary Safra and Wadha Breeds
Authors: Sabha Bassam H. , Masood Afshan , Alanazi Ibrahim O. , Alfadda Assim A. , Almehdar Hussein A. , Benabdelkamel Hicham , Redwan Elrashdy M.
Published: May 2020

Camel milk is traditionally known to have medicinal properties and many potential health benefits. Natural milk contains many soluble proteins and nanoparticles, such as a milk fat globule membrane (MFGM), a three-layered membrane covering of milk fat globule mainly composed of proteins and lipids, which plays an important role in human health. MFGM proteins account for 1%–4% of total milk proteins, and their nutritive value and distribution depends on the different breeds. The differential composition of these membrane proteins among different camel breeds has not been explored. The current study, therefore, aimed to quantitatively analyze and compare the MFGM proteome between the milk produced by the two most common Saudi camel breeds, Camelus dromedarius: Safra and Wadha. Two-dimensional difference in gel electrophoresis (2D-DIGE) and mass spectrometry analysis revealed a total of 44 MFGM proteins that were identified with a significant difference in abundance (p ≤ 0.05; fold change ≥ 1.5) between the two breeds. Thirty-one proteins were up-regulated and 13 proteins were down-regulated in the Safra breed compared to the Wadha breed. The proteins identified with an increased abundance included α-lactalbumin, lactadherin, and annexin a8, whereas the down-regulated proteins included butyrophilin subfamily 1 member a1, lactotransferrin, and vinculin. The differentially abundant proteins were analyzed by the UNIPROT system and gene ontology (GO) to reveal their associations with known biological functions and pathways. Enzyme-linked immunosorbent assay (ELISA) confirmed the 2D-DIGE findings of butyrophilin (BTN) and α-lactalbumin (α-LA) levels obtained from Safra and Wadha breeds.
Bivalent Metal-Chelating Properties of Harzianic Acid Produced by Trichoderma pleuroticola Associated to the Gastropod Melarhaphe neritoides
Authors: De Tommaso Gaetano , Salvatore Maria Michela , Nicoletti Rosario , DellaGreca Marina , Vinale Francesco , Bottiglieri Assunta , Staropoli Alessia , Salvatore Francesco , Lorito Matteo , Iuliano Mauro , Andolfi Anna
Published: May 2020

Harzianic acid is a secondary metabolite of Trichoderma, structurally belonging to the dienyltetramic acid subgroup of the tetramic acids. Biological activities of harzianic acid are of great interest for its antimicrobial and plant growth-promoting activities, which might be related to its chelating properties. In the present work harzianic acid, isolated from cultures of a strain of Trichoderma pleuroticola associated to the gastropod Melarhaphe neritoides, was studied as a complexant agent of a number of biologically relevant transition metals (i.e., Zn2+, Fe2+, Cu2+, and Mn2+), using UV-VIS, potentiometry, MS and NMR techniques. Our findings show the coordination capacity of harzianic acid toward the above cations through the formation of neutral or charged complexes in a variable ratio depending on the metal and pH conditions.
Nanoparticles to Improve the Efficacy of Vaccines
Authors: Yun Cheol-Heui , Cho Chong-Su
Published: May 2020

This editorial aims to summarize the nine scientific papers that contributed to the Special Issue entitled ‘Nanoparticles to Improve the Efficacy of Vaccines’.
The Role of Mechanoperception in Plant Cell Wall Integrity Maintenance
Authors: Bacete Laura , Hamann Thorsten
Published: May 2020

The plant cell walls surrounding all plant cells are highly dynamic structures, which change their composition and organization in response to chemical and physical stimuli originating both in the environment and in plants themselves. They are intricately involved in all interactions between plants and their environment while also providing adaptive structural support during plant growth and development. A key mechanism contributing to these adaptive changes is the cell wall integrity (CWI) maintenance mechanism. It monitors and maintains the functional integrity of cell walls by initiating adaptive changes in cellular and cell wall metabolism. Despite its importance, both our understanding of its mode of action and knowledge regarding the molecular components that form it are limited. Intriguingly, the available evidence implicates mechanosensing in the mechanism. Here, we provide an overview of the knowledge available regarding the molecular mechanisms involved in and discuss how mechanoperception and signal transduction may contribute to plant CWI maintenance.
Transcriptome Analysis of Jojoba (Simmondsia chinensis) during Seed Development and Liquid Wax Ester Biosynthesis
Authors: Alotaibi Saqer S. , Elseehy Mona M. , Aljuaid Bandar S. , El-Shehawi Ahmed M.
Published: May 2020

Jojoba is one of the main two known plant source of natural liquid wax ester for use in various applications, including cosmetics, pharmaceuticals, and biofuel. Due to the lack of transcriptomic and genomic data on lipid biosynthesis and accumulation, molecular marker breeding has been used to improve jojoba oil production and quality. In the current study, the transcriptome of developing jojoba seeds was investigated using the Illunina NovaSeq 6000 system, 100 × 106 paired end reads, an average length of 100 bp, and a sequence depth of 12 Gb per sample. A total of 176,106 unigenes were detected with an average contig length of 201 bp. Gene Ontology (GO) showed that the detected unigenes were distributed in the three GO groups biological processes (BP, 5.53%), cellular component (CC, 6.06%), and molecular functions (MF, 5.88%) and distributed in 67 functional groups. The lipid biosynthesis pathway was established based on the expression of lipid biosynthesis genes, fatty acid (FA) biosynthesis, FA desaturation, FA elongation, fatty alcohol biosynthesis, triacylglycerol (TAG) biosynthesis, phospholipid metabolism, wax ester biosynthesis, and lipid transfer and storage genes. The detection of these categories of genes confirms the presence of an efficient lipid biosynthesis and accumulation system in developing jojoba seeds. The results of this study will significantly enhance the current understanding of wax ester biology in jojoba seeds and open new routes for the improvement of jojoba oil production and quality through biotechnology applications.
Antitumoral Drug-Loaded Biocompatible Polymeric Nanoparticles Obtained by Non-Aqueous Emulsion Polymerization
Authors: Daraba Oana Maria , Cadinoiu Anca Niculina , Rata Delia Mihaela , Atanase Leonard Ionut , Vochita Gabriela
Published: May 2020

Non-aqueous dispersions (NAD) with two types of polymeric nanoparticles (NPs), such as hydrophobic poly(ε-caprolactone) (PCL) and hydrophilic cross-linked poly(vinylpyrrolidone) (PNVP), were synthesized in the present study starting from monomer-in-silicone oil (PDMS) polymerizable non-aqueous emulsions stabilized with the same tailor-made PDMS-based block copolymer. These NPs were loaded with CCisplatin, an antitumoral model drug, directly from the emulsion polymerization step, and it was observed that the presence of the drug leads only to a slight increase of the NPs size, from 120 to 150 nm. The drug release kinetics was evaluated at 37 °C in phosphate buffer at pH = 7.4 and it appeared that the drug release rate from the hydrophilic cross-linked PNVP-based NPs is higher than that from the hydrophobic PCL-based NPs. Moreover, haemolysis tests revealed the fact that these two types of NPs have a good compatibility with the blood. Furthermore, for both the free and drug-loaded NPs, the in vitro cytotoxicity and apoptosis was studied on two types of cancer cell lines, such as MCF-7 (breast cancer cell line) and A-375 (skin cancer cell line). Both types of NPs had no cytotoxic effect but, at a concentration of 500 μg/mL, presented an apoptotic effect similar to that of the free drug.
Accelerated Shape Forming and Recovering, Induction, and Release of Adhesiveness of Conductive Carbon Nanotube/Epoxy Composites by Joule Heating
Authors: Slobodian Petr , Riha Pavel , Olejnik Robert , Matyas Jiri
Published: May 2020

The versatile properties of a nanopaper consisting of a porous network of multi-walled carbon nanotubes were applied to enhance the mechanical and electrical properties of a thermosetting epoxy polymer. The embedded nanopaper proved useful both in the monitoring of the curing process of the epoxy resin by the self-regulating Joule heating and in the supervising of tensile deformations of the composite by detecting changes in its electrical resistance. When heated by Joule heating above its glass transition temperature, the embedded carbon nanotube nanopaper accelerated not only the modelling of the composites into various shapes, but also the shape recovery process, wherein the stress in the nanopaper was released and the shape of the composite reverted to its original configuration. Lastly, in comparison with its respective epoxy adhesive, the internally heated electro-conductive carbon nanotube nanopaper/epoxy composite not only substantially shortened curing time while retaining comparable strength of the adhesive bonding of the steel surfaces, but also enabled a release of such bonds by repeated application of DC current.
Effect of E-Beam Irradiation on Thermal and Mechanical Properties of Ester Elastomers Containing Multifunctional Alcohols
Authors: Piątek-Hnat Marta , Bomba Kuba , Pęksiński Jakub , Kozłowska Agnieszka , Sośnicki Jacek G. , Idzik Tomasz J.
Published: May 2020

The aim of this work was to investigate the thermal and mechanical properties of novel, electron beam-modified ester elastomers containing multifunctional alcohols. Polymers tested in this work consist of two blocks: sebacic acid–butylene glycol block and sebacic acid–sugar alcohol block. Different sugar alcohols were utilized in the polymer synthesis: glycerol, sorbitol, xylitol, erythritol, and mannitol. The polymers have undergone an irradiation procedure. The materials were irradiated with doses of 50 kGy, 100 kGy, and 150 kGy. The expected effect of using ionizing radiation was crosslinking process and improvement of the mechanical properties. Additionally, a beneficial side effect of the irradiation process is sterilization of the affected materials. It is also worth noting that the materials described in this paper do not require either sensitizers or cross-linking agent in order to perform radiation modification. Radiation-modified poly(polyol sebacate-co-butylene sebacate) elastomers have been characterized in respect to the mechanical properties (quasi-static tensile tests), cross-link density, thermal properties (Differential Scanning Calorimetry (DSC)), chemical properties: Fourier transform infrared spectroscopy (FTIR), and wettability (water contact angle). Poly(polyol sebacate-co-butylene sebacate) preopolymers were characterized with nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR) and gel permeation chromatography (GPC). Thermal stability of cross-linked materials (directly after synthesis process) was tested with thermogravimetric analysis (TGA).
The Synthetization and Analysis of Dicyclopentadiene and Ethylidene-Norbornene Microcapsule Systems
Authors: Vintila Ionut Sebastian , Iovu Horia , Alcea Andreea , Cucuruz Andreia , Mandoc Andrei Cristian , Vasile Bogdan Stefan
Published: May 2020

The activities of this paper were focused on an in-situ fabrication process for producing two self-healing systems containing dicyclopentadiene and 5-ethylidene-2-norbornene monomers encapsulated in a urea-formaldehyde shell and integration methods applied in the epoxy matrix to analyse and compare the influences of their integration into the neat epoxy matrix. The self-healing systems were first synthesized according to a literature review, and subsequently, an optimization process was conducted for the fabrication process. Neat epoxy specimens were fabricated as reference specimens and subjected to flexural tests. Several integration methods for incorporating the self-healing systems into the epoxy resin were investigated. The optimal method presenting the best dispersion of the healing system was achieved by reducing the viscosity of the epoxy matrix with 10 vol % acetone solution, the addition of a microcapsule in the matrix, and homogenization at 60 °C at 100 rpm. Thermal analysis was performed in order to observe the mass loss obtained with an increasing temperature and phase changes for both poly-urea-formaldehyde (PUF)-dicyclopentadiene (DCPD) and melamine-urea-formaldehyde (MUF)-5-ethylidene-2-norbornene (ENB) systems. The thermogravimetric analysis performed for the PUF-DCPD system indicates a total loss of mass in the range of 30–500 °C of 72.604% and for the MUF-ENB system, indicates a total mass loss in the range of 30–500 °C of 74.093%. Three-point bending tests showed higher mechanical properties for PUF-DCPD (80%) than MUF-ENB (40%) compared to the neat epoxy systems. Numerical simulations were performed to obtain a better understanding of the microcapsule behavior when embedded in an epoxy matrix.
Combined Molecular Dynamics and DFT Simulation Study of the Molecular and Polymer Properties of a Catechol-Based Cyclic Oligomer of Polyether Ether Ketone
Authors: Varadwaj Pradeep
Published: May 2020

The geometrical, energetic, noncovalent, and material properties of a catechol-based cyclic oligomer of Polyether Ether Ketone (PEEK) called o-PEEK were investigated using Molecular Dynamics (MD) and Density Functional Theory (DFT) simulations. The DFT (and MD) calculation performed with the PBEsol functional (and COMPASS II force field) gave a density of 1.39 (and 1.36) gcm−3 and a volume of 2744.5 (and 2808.5) cm3 for o-PEEK and are comparable with the corresponding experimental values of 1.328 gcm−3 and 2884.6 cm3, respectively. The absolute values of the glass transition temperature (Tg) MD simulated using the unit-cell and 2 × 2 × 2 supercell geometries of the o-PEEK system were 424.4 and 428.6 K, respectively. Although these values slightly differ from each other, both are close to the experiment (Tg = 418.2 K). The results of the (charge) density gradient analysis suggest that the supramolecular assembly between the o-PEEK oligomers in the experimentally observed infinite semi-crystal is driven by a wide range of noncovalent interactions. While the individual local interactions between the oligomers were recognized to be weak-to-medium in strength and are theoretically difficult to quantify, the B97-D3/cc-pVTZ level stabilization energy responsible for the formation of each of the five binary complex configurations extracted from the PBEsol relaxed 2 × 2 × 2 supercell geometry of the o-PEEK system was calculated to vary between –3.5 and –33.0 kcal mol−1.
Implementation Criteria for Intelligent Systems in Motor Production Line Process Management
Authors: Lin Yao-Chin , Yeh Ching-Chuan , Chen Wei-Hung , Hsu Kai-Yen
Published: May 2020

In this study, the factors that affect the implementation of intelligent systems in motor production lines are analyzed. A motor production line located in Vietnam is used as the research object. The research methods include secondary data collection, field study, and interviews. This study demonstrates the following: firstly, the implementation of intelligent systems in motor production lines is heading toward Industry 4.0. Secondly, it is proposed that three functional systems—robot arm, image recognition, and big data analysis—can be introduced in the motor production line. This study analyzes the process involved in coil and motor production lines and attempts to combine intelligent system functions. It is expected that in the future, manpower will be reduced, production line productivity will increase, and intelligent production lines will be proposed. The factors that affect the introduction of intelligent systems in motor production lines are improved, and the importance of intelligent systems, which has been rarely considered in previous studies, is highlighted. In the implementation criteria of the intelligent system in the process management of the motor production line, this study provides some suggestions (to coil and motor assembly line) for the production process management. These suggestions can be provided as a reference for production lines that acquaint with intelligent systems.
Expression of Wilm’s Tumor Gene (WT1) in Endometrium with Potential Link to Gestational Vascular Transformation
Authors: Zhang Peilin
Published: May 2020

Background: Wilm’s tumor 1 gene (WT1) is a transcription factor with versatile cellular functions in embryonic development, the maintenance of adult tissue functions, and regeneration. WT1 is known to be regulated by progesterone and it is abundantly expressed in endometrium, but its function is unclear. Design: in this observational and descriptive study, WT1 expression was detected by immunohistochemical staining in endometrium of various physiological and pathological conditions. Result: WT1 was detected in endometrial stromal cells and vascular smooth muscle cells, in both proliferative and secretory phases of menstrual cycles. WT1 appeared increased in vascular smooth muscle cells in spiral artery in early pregnancy and it was also detected in regenerative endothelial cells and smooth muscle cells in decidual vasculopathy at term. WT1 expression appeared decreased in endometrial stromal cells in adenomyosis (endometriosis). Conclusion: WT1 potentially links the hormonal effects on endometrial decidualization and may play a role in gestational vascular transformation during pregnancy and restoration after pregnancy.
The Advantages of Industry 4.0 Applications for Sustainability: Results from a Sample of Manufacturing Companies
Authors: Brozzi Riccardo , Forti David , Rauch Erwin , Matt Dominik T.
Published: May 2020

Far from being exclusively related to economic considerations, the advantages of Industry 4.0 applications also include environmental and social concerns. An increasing amount of scientific publications relate the implementation of the fourth industrial revolution paradigm to sustainability. Several studies reported opportunities of Industry 4.0 implementation particularly to the environmental dimension of sustainability, e.g., through improved logistics streams and lowered waste from production. The present research aims at providing evidence on whether manufacturing companies consider Industry 4.0 implementation as an advantage contributing to environmental and social sustainability in terms of lower environmental impact of production, as well as higher physical relief for workers and flexibility of work organisation. The results were an attempt to study such relations with company sizes, industry sectors, turnover and self-assessed levels of digitalization varying. The sample encompasses 65 companies located in the Marche region (Italy). The results show that overall the perception of economic opportunities prevail, while the association of a beneficial impact of Industry 4.0 on environmental sustainability is rather low across companies, regardless of their size, turnover and digital level. As for the statistically significant variables, the results suggest a strong association of the size and the digital level to specific Industry 4.0 related advantages, referring to the social and economic dimension of sustainability, respectively.
Ship Speed Optimization Considering Ocean Currents to Enhance Environmental Sustainability in Maritime Shipping
Authors: Yang Liqian , Chen Gang , Zhao Jinlou , Rytter Niels Gorm Malý
Published: May 2020

Enhancing environmental sustainability in maritime shipping has emerged as an important topic for both firms in shipping-related industries and policy makers. Speed optimization has been proven to be one of the most effective operational measures to achieve this goal, as fuel consumption and greenhouse gas (GHG) emissions of a ship are very sensitive to its sailing speed. Existing research on ship speed optimization does not differentiate speed through water (STW) from speed over ground (SOG) when formulating the fuel consumption function and the sailing time function. Aiming to fill this research gap, we propose a speed optimization model for a fixed ship route to minimize the total fuel consumption over the whole voyage, in which the influence of ocean currents is taken into account. As the difference between STW and SOG is mainly due to ocean currents, the proposed model is capable of distinguishing STW from SOG. Thus, in the proposed model, the ship’s fuel consumption and sailing time can be determined with the correct speed. A case study on a real voyage for an oil products tanker shows that: (a) the average relative error between the estimated SOG and the measured SOG can be reduced from 4.75% to 1.36% across sailing segments, if the influence of ocean currents is taken into account, and (b) the proposed model can enable the selected oil products tanker to save 2.20% of bunker fuel and reduce 26.12 MT of CO2 emissions for a 280-h voyage. The proposed model can be used as a practical and robust decision support tool for voyage planners/managers to reduce the fuel consumption and GHG emissions of a ship.
A Sectoral Eco-Efficiency Analysis on Urban-Industrial Symbiosis
Authors: Bian Yuli , Dong Liang , Liu Zhaowen , Zhang Lezhu
Published: May 2020

Urban-industrial symbiosis (UIS) is an important system innovation via sectors integration, and has been widely recognized as a novel pathway for achieving regional eco-industrial development. Eco-efficiency, as a mature approach and indicator, offers an effective tool to uncover both the status and trends of such a transformation. However, most studies have focused on the whole industry or city as a whole, which has meant that a view from the sectoral level focusing on UIS was missing. To fill this research gap, this paper applied a modified eco-efficiency approach using integrating input–output analysis (IOA) and carbon footprint (CFP) to identify the eco-efficiency benefits of UIS from a sectoral level. Specifically, sector-level economic data (as economic outputs) and CFP (as environmental impacts) are used to calculate the sectoral eco-efficiency. IOA helps to offer sectoral economic data, and, with integrating process-based inventory analysis, to conduct a CFP calculation at the sectoral level. To test the feasibility of the developed approach, urban industrial symbiosis scenarios in one typical industrial city of China were analyzed. This city is held up as the national pilot of the circular economy, low-carbon city, and ecological civilization in China. Scenarios analysis on a business as usual (no UIS) and with UIS implementation in 2012 were undertaken and compared with the change of sectoral CFP and eco-efficiency. The results highlighted a moderate increase in eco-efficiency and trade-offs in certain sectors, indicating that UIS was moderately effective in increasing the urban resource efficiency from a sectoral level, but a refined design was required. Policy recommendations are made based on the analytical results, to inform decision makers and urban and industrial managers seeking to improve the implementation of UIS as a means of achieving greater urban sustainability.
Pennisetum sinese: A Potential Phytoremediation Plant for Chromium Deletion from Soil
Authors: Chen Xiaofei , Tong Jianhua , Su Yi , Xiao Langtao
Published: May 2020

Chromium is one of the major pollutants in water and soil. Thus, it is urgent to develop a new method for chromium removal from the environment. Phytoremediation is a promising approach for heavy metal pollution recovery. As a perennial giant grass with a fast growth rate, Pennisetum sinese has been widely used as livestock feed, mushroom culture medium and biomass energy raw material. Interestingly, we have found a high adsorption capacity of P. sinese for chromium. P. sinese was treated with different concentrations of chromium for 15 days. Results showed that P. sinese plantlets grew well under low concentrations (less than 500 μM) of chromium (VI). The plantlet growth was inhibited when treated with high concentrations of chromium (more than 1000 μM). Up to 150.99 and 979.03 mg·kg−1 DW of chromium accumulated in the aerial part and root, respectively, under a treatment of 2000 μM Cr. The bioaccumulation factor (BCF) of P. sinese varied from 10.87 to 17.56, and reached a maximum value at the concentration of 500 μM. The results indicated that P. sinese showed strong tolerance and high accumulation capability under Cr stress. Therefore, the chromium removal potential of P. sinese has a great application prospect in phytoremediation.
Wave Energy Potential and Simulation on the Andaman Sea Coast of Thailand
Authors: Foyhirun Chutipat , Kositgittiwong Duangrudee , Ekkawatpanit Chaiwat
Published: May 2020

Ocean wave energy is an interesting renewable energy because it will never run out and can be available all the time. If the wave energy is to be used, then the feasibility study of localized wave potential has to be studied. This goal is to study the potential of waves in the Andaman Sea. The Simulating WAves Nearshore (SWAN) model was used to calculate the significant wave heights, which were validated with the measurement data of the Jason-2 satellite. The coastal area of Phuket and Phang Nga provinces are suitable locations for studying wave energy converters because they have high significant wave height. Moreover, this study used computational fluid dynamics (CFD) for the simulation of wave behavior in accordance with wave parameters from the SWAN model. The wave height simulated from CFD was validated with linear wave theory. The results found that it was in good agreement with linear wave theory. It can be applied for a simulation of the wave energy converter.
Teleworking in the Context of the Covid-19 Crisis
Authors: Belzunegui-Eraso Angel , Erro-Garcés Amaya
Published: May 2020

This article aims to analyze the implementation of teleworking as a security practice to face the crisis resulting from the Covid-19 disease. The present paper provides both theoretical and practical results. From a theoretical standpoint, the Baruch and Nicholson approach is extended with environmental, safety, and legal factors that explain telework. From a practical perspective, a database of companies that have introduced telework as a measure to face coronavirus in a crisis context has been obtained. In short, the Covid-19 crisis demonstrates how teleworking has been used by companies to ensure their employees’ safety and to provide continuity to economic activity. Consequently, safety factors are relevant in the study of teleworking and should be considered in further research.
Evidence That Forage-Fed Cows Can Enhance Milk Quality
Authors: Davis Hannah , Chatzidimitriou Eleni , Leifert Carlo , Butler Gillian
Published: May 2020

Researching the distinguishing factors of nutritional milk quality is key to sustainable production and addresses increasing media and scientific scrutiny regarding human health effects and ecological impacts of dairy products. Modern Western diets have high omega-6 relative to omega-3 fatty acid (FA) consumption. This ratio in milk can be manipulated by management practices; increasing forage in dairy diets raises omega-3 in milk. Whilst studies identify higher concentrations of nutritionally beneficial FAs in organic dairy, milk from 100% forage-fed cows in the UK has not been investigated. This study explores differences in FA composition between supermarket conventional and organic and Pasture for Life Association (PFLA) milk, collected in April, July and October, 2017. PFLA milk had higher concentrations of conjugated linoleic acid (+94%) and omega-3 (+92%) than conventional milk. Additionally, concentrations of palmitic acid (+11%), omega-6 (+69%) and the ratio of omega-6/omega-3 (+201%) were higher in conventional than PFLA milk. PFLA milk had higher concentrations of alpha-linolenic acid (+39%), conjugated linoleic acid (+30%) and omega-3 (+21%) and lower concentrations of omega-6 (−36%) and a lower ratio of omega-6/omega-3 (−44%) than organic milk. This supports previous studies and demonstrates the scope to improve milk FA profiles further for potential health benefits through pasture-based management.
Assessing Resilience of Urban Critical Infrastructure Networks: A Case Study of Ahvaz, Iran
Authors: Alizadeh Hadi , Sharifi Ayyoob
Published: May 2020

Cities around the world increasingly recognize the need to build on their resilience to deal with the converging forces of urbanization and climate change. Given the significance of critical infrastructure for maintaining quality of life in cities, improving their resilience is of high importance to planners and policy makers. The main purpose of this study is to spatially analyze the resilience of water, electricity, and gas critical infrastructure networks in Ahvaz, a major Iranian city that has been hit by various disastrous events over the past few years. Towards this goal, we first conducted a two-round Delphi survey to identify criteria that can be used for determining resilience of critical infrastructure networks across different parts of the city. The selected criteria that were used for spatial analysis are related to the physical texture, the design pattern, and the scale of service provision of the critical infrastructure networks. Results showed that, overall, critical infrastructure networks in Ahvaz do not perform well against the measurement criteria. This is specially the case in Regions 1, 2, 4, and 6, which are characterized by issues such as old and centralized infrastructure networks and high levels of population density. The study highlights the need to make improvements in terms of the robustness, redundancy, and flexibility of the critical infrastructure networks in the city.
Quantitative Determination of Some Parameters in the Tennant Method and Its Application to Sustainability: A Case Study of the Yarkand River, Xinjiang, China
Authors: Fu Aihong , Wang Yi , Ye Zhaoxia
Published: May 2020

Analysis of basic eco-environmental water requirements (BEEWRs) along inland rivers characterized by extreme aridity can provide a theoretical basis for sustaining riverine ecosystems stressed by increasingly dry conditions and human activity. In the past, analyzing the ecological base flow as determined by the Tennant method was the predominant method used to calculate the BEEWR of a river. However, some parameter values within this method are determined subjectively, increasing uncertainty in the estimated values. In this paper, quantitative methods for these subjectively determined parameters are proposed and used to analyze the BEEWR of the Yarkand River, Xinjiang, China. The results demonstrate that: (1) the flood and non-flood seasons of a river can be delineated by analyzing the increase rate of monthly runoff as compared to the monthly runoff of the previous month; (2) the ecological base flow standard in the Tennant method can be more quantitatively determined by comparing the BEEWR for each ecological base flow standard to the annual average river loss, where the BEEWR must exceed the annual average river loss; and (3) BEEWRs of other up- and downstream river reaches can be obtained using the formula “BEEWR in the next downstream section equals the BEEWR in the last section minus the river loss between these two sections”.
Mountain Meadows and Glades of the Carpathians—Type or Element of Landscape? The Problem of Delimitation and Typology of Mountain Pasture Landscapes
Authors: Sobala Michał
Published: May 2020

The typologies of landscapes of individual states that have ratified the European Landscape Convention do not include mountain pasture landscapes. Pasture landscapes in the Carpathians are preserved in a relatively good condition, although their spatial extent has considerably shrunk over the last few decades. The article demonstrates that mountain meadows and glades in the Carpathians meet all the conditions that allow them to be classified as a type of landscape, and thus they should be included in national typologies of landscapes. Firstly, they constitute a set of natural (non-forest vegetation) and anthropogenic (traditional shepherding buildings) objects. Secondly, they are a dynamic system in which natural, social and economic processes take place. They are also a source of stimuli, affecting different human senses and values and are a system that provides various real and potential services. The inclusion of mountain pasture landscapes in national typologies may provide a stronger basis for their protection.
Measuring Progress toward Urban Sustainability: Do Global Measures Work for Arctic Cities?
Authors: Berman Matthew , Orttung Robert W.
Published: May 2020

The International Organization for Standardization recently responded to a growing global interest in cities by developing an index for measuring urban sustainability (ISO 37120). We address how well this standard applies to Arctic cities, and potential modifications that might improve its performance. After briefly discussing the goals of sustainability indicators, we examine the extent to which Arctic cities’ remote location, cold and changing climate, and thin, largely resource-based economies may create different sustainability challenges. We then critically examine the content of ISO 37120 and the context in which it was created. We place the index within a broader discussion of urban sustainability indicators and examine the extent to which it really addresses sustainability. We then analyze how well the ISO 37120 accounts for the characteristic features of Arctic cities that produce unique sustainability challenges. Our findings show that only half of ISO 37120′s 128 indicators actually measure future-oriented concerns. We suggest that, while the ISO 37120 may be a useful starting point in quantifying Arctic urban sustainability, the index should only be used as a foundation for a more in-depth analysis. To better represent Arctic cities, the ISO 37120 would need to include indicators that situate cities within their regional contexts, addressing both remoteness and the underlying basis of the Arctic city economy. The index should also measure the role of Indigenous populations, and chart the extent to which cities are working to increase levels of sustainability.
Drivers of Sustainable Adoption of Building Information Modelling (BIM) in the Nigerian Construction Small and Medium-Sized Enterprises (SMEs)
Authors: Saka Abdullahi B. , Chan Daniel W. M. , Siu Francis M. F.
Published: May 2020

The small and medium-sized enterprises (SMEs) which are the backbone of any economy are often on the disadvantaged side of the digital divide in the construction industry. With the advent of building information modelling (BIM), the SMEs are facing challenges and are slow with its uptake. Hitherto, extant research studies on BIM have focused primarily on the large firms and there is an observed trend of underrepresentation of the SMEs in BIM studies. Thus, this paper aims to investigate the major drivers of sustainable adoption of Building Information Modelling in SMEs and the dynamics of these drivers in developing countries using interpretive structural modelling approach and Matrice d’Impacts croises-multipication applique a classement (MICMAC) analysis. The findings reveal that organizational readiness is of utmost importance for the proliferation of BIM in SMEs. Also, the independent drivers which are the most important drivers consist of BIM characteristics, internal and external environment drivers and thus portray the BIM adoption as a complex socio-technical system. This study categorizes the drivers for easy intervention of SMEs’ managers and policymakers. It contributes to the nascent studies of BIM adoption in SMEs of developing countries.
Fourth-Order Difference Approximation for Time-Fractional Modified Sub-Diffusion Equation
Authors: Ali Umair , Sohail Muhammad , Usman Muhammad , Abdullah Farah Aini , Khan Ilyas , Nisar Kottakkaran Sooppy
Published: May 2020

Fractional differential equations describe nature adequately because of the symmetry properties which describe physical and biological processes. In this article, a fourth-order new implicit difference scheme is formulated and applied to solve the two-dimensional time-fractional modified sub-diffusion equation involving two times Riemann–Liouville fractional derivatives. The stability of the fourth-order implicit difference scheme is investigated using the von Neumann technique. The proposed scheme is shown to be unconditionally stable. Numerical examples are given to illustrate the feasibility of the proposed scheme.
Frequency-Selective Wallpaper for Indoor Interference Reduction and MIMO Capacity Improvement
Authors: Rodríguez José-Víctor , Gustafsson Mats , Molina-García-Pardo José-María , Juan-Llácer Leandro , Rodríguez-Rodríguez Ignacio
Published: May 2020

This paper presents the design and features of frequency-selective wallpaper—based on periodic and symmetric metallic hexagons—intended to be attached to standard walls for filtering out 5 GHz signals (e.g., IEEE 802.11a systems) without blocking other selected radio communication services (e.g., cellular mobile communication signals). It analyzes the characteristics of the radio channel—as found within standard indoor environments—with both regular walls and walls with the proposed frequency-selective wallpaper, examined using a ray-launching program for single-input single-output (SISO) and multiple-input multiple-output (MIMO) systems. This allows the harvesting of parameters, including channel capacity, power delay profile, and signal-to-interference ratio, for proper comparison between the two environments under study: with and without the presented wallpaper. The achieved results clearly show that the use of the proposed frequency-selective wallpaper in an indoor scenario reduces interference levels by an additional attenuation of up to 20 dB in comparison to an unpapered wall. Additionally, with MIMO systems, radio channel characteristics, such as capacity, are improved due to the increase in the magnitude of all singular values of the channel transfer matrix compared to the unpapered wall case, thereby leading to the existence of more relevant subchannels.
On the Integrable Chaplygin Type Hydrodynamic Systems and Their Geometric Structure
Authors: Prykarpatskyy Yarema
Published: May 2020

A class of spatially one-dimensional completely integrable Chaplygin hydrodynamic systems was studied within framework of Lie-algebraic approach. The Chaplygin hydrodynamic systems were considered as differential systems on the torus. It has been shown that the geometric structure of the systems under analysis has strong relationship with diffeomorphism group orbits on them. It has allowed to find a new infinite hierarchy of integrable Chaplygin like hydrodynamic systems.
On the Chebyshev Polynomials and Some of Their Reciprocal Sums
Authors: Zhang Wenpeng , Han Di
Published: May 2020

In this paper, we utilize the mathematical induction, the properties of symmetric polynomial sequences and Chebyshev polynomials to study the calculating problems of a certain reciprocal sums of Chebyshev polynomials, and give two interesting identities for them. These formulae not only reveal the close relationship between the trigonometric function and the Riemann ζ-function, but also generalized some existing results. At the same time, an error in an existing reference is corrected.