bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel Materials for Sustainable Energy Conversion and Storage
Authors: Kim Jung Kyu
Published: June 2020

Sustainability is highly desired for human beings due to a rapidly changing global climate and numerous environmental issues. In past decades, state-of-the-art studies have been extensively conducted to achieve sustainable energy conversion and storage. However, the remaining challenges in the commercialization of energy conversion and storage devices are to develop novel materials and advanced manufacturing processes. Furthermore, the engineering of nanostructures and device-architectures is of great importance for the energy conversion and storage flat forms. This Special Issue “Novel Materials for Sustainable Energy Conversion and Storage” aims the state-of-the-art research reports of novel nanomaterials and the engineering of device architectures for divergent energy conversion and storage applications with high sustainability involving solar energy systems, electrochemical cells, artificial photosynthesis or secondary (rechargeable) batteries, as highlighted in this editorial.
Characterization of Damage Evolution on Hot Flat Rolled Mild Steel Sheets by Means of Micromagnetic Parameters and Fatigue Strength Determination
Authors: Teschke Mirko , Rozo Vasquez Julian , Lücker Lukas , Walther Frank
Published: June 2020

In continuous casting processes, inevitable voids (damage) are generated inside the material. The subsequent forming process of hot flat rolling offers the potential of healing these defects by closing the voids and bonding the internal surfaces. In this paper, different forming conditions from hot flat rolling process were characterized with micromagnetic measurement techniques and the influence of the damage evolution on the fatigue behavior was investigated. To characterize the reduction of voids through hot flat rolling processes, nondestructive testing techniques are required. Therefore, micromagnetic measurements such as Barkhausen noise, incremental permeability, and harmonic analysis were carried out, correlated with the number of voids, and compared with each other. The influence of damage evolution of different forming conditions on the fatigue behavior was characterized based on instrumented constant amplitude and multiple amplitude (load increase) tests. A significant increase in fatigue strength due to the hot flat rolling process, which leads to a reduction in the number of voids, was observed. In addition, the fracture surfaces of the specimens were analyzed in the scanning electron microscope.
Elastic Critical Moment for the Lateral–Torsional Buckling (LTB) Analysis of Structural Glass Beams with Discrete Mechanical Lateral Restraints
Authors: Santo Dario , Mattei Silvana , Bedon Chiara
Published: June 2020

Structural glass beams and fins are largely used in buildings, in the form of primary load-bearing members and bracing systems for roof or facade panels. Several loading and boundary conditions can be efficiently solved by means of bonded composites that involve the use of laminated glass sections. Additionally, the so-obtained glass members are often characterized by high slenderness. To this aim, several literature studies were dedicated to the lateral–torsional buckling (LTB) behavior of laterally unrestrained (LU) glass elements, with the support of full-scale experiments, analytical models, or finite element (FE) numerical investigations. Standardized design recommendations for LU glass members in LTB are available for designers. However, several design issues still require “ad hoc” (and often expensive) calculation studies. In most of the cases, for example, the mechanical interaction between the structural components to verify involves various typologies of joints, including continuous sealant connections, mechanical point fixings, or hybrid solutions. As a result, an accurate estimation of the theoretical LTB critical moment for such a kind of laterally restrained (LR) element represents a first key issue toward the definition and calibration of generalized design recommendations. Careful consideration should be spent for the description of the intrinsic features of materials in use, as well as for a combination of geometrical and mechanical aspects (i.e., geometry, number, position of restraints, etc.). In this paper, the attention is focused on the calculation of the elastic critical buckling moment of LR glass beams in LTB. Existing analytical approaches of the literature (mostly developed for steel constructional members) are briefly recalled. An additional advantage for extended parametric calculations is then taken from finite element (FE) numerical analyses, which are performed via the LTBeam or the ABAQUS software codes. The actual role and the effect of discrete mechanical restraints are, thus, explored for selected configurations of practical interest. Finally, the reliability of simplified calculation approaches is assessed.
Influence of the Layer Directions on the Properties of 316L Stainless Steel Parts Fabricated through Fused Deposition of Metals
Authors: Kurose Takashi , Abe Yoshifumi , Santos Marcelo V. A. , Kanaya Yota , Ishigami Akira , Tanaka Shigeo , Ito Hiroshi
Published: June 2020

Metal specimens were fabricated via the fused deposition of metals (FDMet) technique with a filament composed of the 316L stainless steel particles and an organic binder. This process was adopted due to its potential as a low-cost additive manufacturing process. The objective of this study is to investigate the influence of the processing conditions—layer directions and layer thicknesses—on the mechanical and shrinkage properties of the metal components. The specimens were printed in three different layer directions. The highest ultimate strength of 453 MPa and strain at break of 48% were obtained in the specimen printed with the layer direction perpendicular to the tensile direction. On the other hand, the specimen printed in the layer direction parallel to the tensile direction exhibited poor mechanical properties. The reason for the anisotropy of the properties was investigated through systematic SEM observations. The observations revealed the presence of segregated binder domains in the filaments. It was deduced that the binder domain was oriented in the direction perpendicular to that of the layer and remained as oriented voids even after sintering. The voids oriented perpendicular to the tensile direction act as defects that could cause stress concentration, thus resulting in poor mechanical properties.
Self-Healing Analysis of Half-Warm Asphalt Mixes Containing Electric Arc Furnace (EAF) Slag and Reclaimed Asphalt Pavement (RAP) Using a Novel Thermomechanical Healing Treatment
Authors: Lizárraga José Manuel , Gallego Juan
Published: June 2020

Nowadays, the self-healing of asphalt pavements promoted by microwave radiation heating energy is gaining attention and strength in the scientific community. However, most of these studies are only conceptual and, thus, remain shrouded in uncertainty regarding technology development, economy, and application effect. Therefore, there are several efforts underway to offer more effective assisted healing treatments that are capable of overcoming such uncertainties. This paper aims to assess and quantify the healing performance rates (HR) of half-warm recycled asphalt (HWRA) mixtures containing electric arc furnace (EAF) slag and total recycled asphalt pavement (RAP) rates. To this end, a novel assisted thermomechanical healing treatment (i.e., a recompaction-based technique and microwave heating energy) was put forward to promote the potential healing effect of this treatment on the mechanical properties of the asphalt mixtures. In order to do this, three microwave heating temperatures (25 °C, 60 °C, and 80 °C) and three mechanical recompaction levels (0, 25, and 50 gyrations) were selected. After that, the healing performance rates (%, HR) of the asphalt mixtures were calculated by repeated indirect tensile strength (ITS) and indirect tensile stiffness modulus (ITSM). The results indicated that the 8% EAF slag mixture was found to provide significant microwave heating energy savings by up to 69% compared with the benchmark 100% RAP mixture, and, at the same time, it experienced a remarkable stiffness recovery response of 140% of the initial mechanical properties. These findings encourage greater confidence in promoting this innovative thermomechanical-based healing treatment for in-situ surface course asphalt mixtures of road pavements.
Deicing Concrete Pavements and Roads with Carbon Nanotubes (CNTs) as Heating Elements
Authors: Kim Hee Su , Ban Hoki , Park Won-Jun
Published: June 2020

Existing deicing technologies involving chloride and heating wires have limitations such as reduced durability of roads and surrounding structures, and high labor requirements and maintenance costs. Hence, in this study, we performed indoor experiments, numerical analyses, and field tests to examine the efficiency of deicing using carbon nanotubes (CNTs) to overcome these limitations. For indoor experiments, a CNT was inserted into the center of a concrete sample and then heated to 60 °C while maintaining the ambient and internal temperatures of the sample at −10 °C using a refrigeration chamber. Numerical analysis considering thermal conductivity was performed based on the indoor experimental results. Using the calculation results, field tests were conducted, and the thermal conduction performance of the heating element was examined. Results showed that the surface temperature between the heating elements exceeded 0 °C. Moreover, we found that the effective heating distance of the heating elements should be 20–30 cm for effective thermal overlap through the indoor experiments. Additionally, the numerical analysis results indicated that the effective heating distance increased to 100 cm when the heating element temperature and experiment time were increased. Field test results showed that 62 cm-deep snow melted between the heating elements (100 cm), thus, verifying the possibility of deicing.
Simulation Studies on Centrifugal MQL-CCA Method of Applying Coolant during Internal Cylindrical Grinding Process
Authors: Kieraś Seweryn , Jakubowski Marek , Nadolny Krzysztof
Published: June 2020

This paper describes simulation studies regarding the application of the centrifugal minimum quantity lubrication (MQL) method simultaneously with the delivery of a compressed cooled air (CCA) stream in the internal cylindrical grinding process. The idea of a new hybrid cooling and lubrication method connecting centrifugal (through a grinding wheel) lubrication by MQL with a CCA stream is described. The methodology of computational fluid dynamics (CFD) simulation studies, as well as the results of numerical simulations, are presented in detail. The aim of the simulations was to determine the most favourable geometrical and kinematic parameters of the system in the context of air-oil aerosol and CCA flow, as well as heat exchange. In the simulation, the variables were the grinding arbor geometrical parameters, the angle of CCA supply line outlets, and the grinding wheel and workpiece peripheral speed. As a result of the simulation studies, the most favourable geometrical parameters were designated, determining the orientation of the ends of the two CCA supply line outlets before and after the grinding zone, the number of openings in the drilled-out grinding arbor, and the influence of the grinding speed on the parameters of the coolant flow and temperature of objects in the grinding zone. In addition, the results of simulation tests made it possible to visualise the velocity vectors of the two-phase coolant flow in a complex system of air-oil aerosol delivery centrifugally through an open structure of a very fast rotating porous layer (grinding wheel), with an additional supply of CCA using an external cold air gun (CAG).
Systemic and Local Biocompatibility Assessment of Graphene Composite Dental Materials in Experimental Mandibular Bone Defect
Authors: Dreanca Alexandra , Sarosi Codruta , Parvu Alina Elena , Blidaru Mihai , Enacrachi George , Purdoiu Robert , Nagy Andras , Sevastre Bogdan , Oros Nechita Adrian , Marcus Ioan , Moldovan Marioara
Published: June 2020

The main objective of this research is to demonstrate the biocompatibility of two experimental graphene dental materials by in vitro and in vivo tests for applications in dentistry. The novel graphene dental materials, including one restorative composite and one dental cement, were subjected to cytotoxicity and implantation tests by using a rat model of a non-critical mandibular defect. In vitro cytotoxicity induced by materials on human dental follicle stem cells (restorative composite) and dysplastic oral keratinocytes (dental cement) was investigated at 37 °C for 24 h. After in vivo implantation, at 7 weeks, bone samples were harvested and subjected to histological investigations. The plasma biochemistry, oxidative stress, and sub-chronic organ toxicity analysis were also performed. The resulting cytotoxicity tests confirm that the materials had no toxic effects against dental cells after 24 h. Following graphene dental materials implantation, the animals did not present any symptoms of acute toxicity or local inflammation. No alterations were detected in relative organ weights and in correlation with hepatic and renal histological findings. The materials’ lack of systemic organ toxicity was confirmed. The outcomes of our study provided further evidence on the graphene dental materials’ ability for bone regeneration and biocompatibility.
EvoPreprocess—Data Preprocessing Framework with Nature-Inspired Optimization Algorithms
Authors: Karakatič Sašo
Published: June 2020

The quality of machine learning models can suffer when inappropriate data is used, which is especially prevalent in high-dimensional and imbalanced data sets. Data preparation and preprocessing can mitigate some problems and can thus result in better models. The use of meta-heuristic and nature-inspired methods for data preprocessing has become common, but these approaches are still not readily available to practitioners with a simple and extendable application programming interface (API). In this paper the EvoPreprocess open-source Python framework, that preprocesses data with the use of evolutionary and nature-inspired optimization algorithms, is presented. The main problems addressed by the framework are data sampling (simultaneous over- and under-sampling data instances), feature selection and data weighting for supervised machine learning problems. EvoPreprocess framework provides a simple object-oriented and parallelized API of the preprocessing tasks and can be used with scikit-learn and imbalanced-learn Python machine learning libraries. The framework uses self-adaptive well-known nature-inspired meta-heuristic algorithms and can easily be extended with custom optimization and evaluation strategies. The paper presents the architecture of the framework, its use, experiment results and comparison to other common preprocessing approaches.
Marine-Inspired Enzymatic Mineralization of Dairy-Derived Whey Protein Isolate (WPI) Hydrogels for Bone Tissue Regeneration
Authors: Norris Karl , Kocot Magdalena , Tryba Anna M. , Chai Feng , Talari Abdullah , Ashton Lorna , Parakhonskiy Bogdan V. , Samal Sangram K. , Blanchemain Nicholas , Pamuła Elżbieta , Douglas Timothy E. L.
Published: June 2020

Whey protein isolate (WPI) is a by-product from the production of cheese and Greek yoghurt comprising β-lactoglobulin (β-lg) (75%). Hydrogels can be produced from WPI solutions through heating; hydrogels can be sterilized by autoclaving. WPI hydrogels have shown cytocompatibility and ability to enhance proliferation and osteogenic differentiation of bone-forming cells. Hence, they have promise in the area of bone tissue regeneration. In contrast to commonly used ceramic minerals for bone regeneration, a major advantage of hydrogels is the ease of their modification by incorporating biologically active substances such as enzymes. Calcium carbonate (CaCO3) is the main inorganic component of the exoskeletons of marine invertebrates. Two polymorphs of CaCO3, calcite and aragonite, have shown the ability to promote bone regeneration. Other authors have reported that the addition of magnesium to inorganic phases has a beneficial effect on bone-forming cell growth. In this study, we employed a biomimetic, marine-inspired approach to mineralize WPI hydrogels with an inorganic phase consisting of CaCO3 (mainly calcite) and CaCO3 enriched with magnesium using the calcifying enzyme urease. The novelty of this study lies in both the enzymatic mineralization of WPI hydrogels and enrichment of the mineral with magnesium. Calcium was incorporated into the mineral formed to a greater extent than magnesium. Increasing the concentration of magnesium in the mineralization medium led to a reduction in the amount and crystallinity of the mineral formed. Biological studies revealed that mineralized and unmineralized hydrogels were not cytotoxic and promoted cell viability to comparable extents (approximately 74% of standard tissue culture polystyrene). The presence of magnesium in the mineral formed had no adverse effect on cell viability. In short, WPI hydrogels, both unmineralized and mineralized with CaCO3 and magnesium-enriched CaCO3, show potential as biomaterials for bone regeneration.
Influences of Combined Organic Fouling and Inorganic Scaling on Flux and Fouling Behaviors in Forward Osmosis
Authors: Chun Youngpil , Jeong Kwanho , Cho Kyung
Published: June 2020

This study investigated the influence of combined organic fouling and inorganic scaling on the flux and fouling behaviors of thin-film composite (TFC) forward osmosis (FO) membranes. Two organic macromolecules, namely, bovine serum albumin (BSA) and sodium alginate (SA), and gypsum (GS), as an inorganic scaling agent, were selected as model foulants. It was found that GS scaling alone caused the most severe flux decline. When a mixture of organic and inorganic foulants was employed, the flux decline was retarded, compared with when the filtration was performed with only the inorganic scaling agent (GS). The early onset of the conditioning layer formation, which was due to the organics, was probably the underlying mechanism for this inhibitory phenomenon, which had suppressed the deposition and growth of the GS crystals. Although the combined fouling resulted in less flux decline, compared with GS scaling alone, the concoction of SA and GS resulted in more fouling and flux decline, compared with the mixture of BSA and GS. This was because of the carboxyl acidity of the alginate, which attracted calcium ions and formed an intermolecular bridge.
Series of Near-IR-Absorbing Transition Metal Complexes with Redox Active Ligands
Authors: Salojärvi Esko , Peuronen Anssi , Lahtinen Manu , Huhtinen Hannu , Vlasenko Leonid S. , Lastusaari Mika , Lehtonen Ari
Published: June 2020

New soluble and intensely near-IR-absorbing transition metal (Ti, Zr, V, Ni) complexes were synthesized using a redox non-innocent N,N’-bis(3,5-di-tertbutyl-2-hydroxy-phenyl) -1,2-phenylenediamine (H4L) as a ligand precursor. In all the complexes, ([Ti(Lox)2, [Zr(Lox)2], [V(Lsq1)(HLox)] and [Ni(HLox)2], two organic molecules coordinate to the metal center as tri- or tetradentate ligands. The solid-state structures of the complexes were determined using single crystal XRD, and the compounds were further characterized with Electrospray Ionisation Mass Spectrometry (ESI-MS). Thermoanalytical measurements indicated the thermal stabilities of the complexes. All compounds absorb strongly in the near-IR region and show very interesting magnetic and electrochemical properties. Moreover, it was shown that the V and Ni complexes can also convert absorbed near-IR photons to (un)paired electrons, which indicates great promise in photovoltaic applications.
Albumin-Binding PSMA Radioligands: Impact of Minimal Structural Changes on the Tissue Distribution Profile
Authors: Deberle Luisa M. , Tschan Viviane J. , Borgna Francesca , Sozzi-Guo Fan , Bernhardt Peter , Schibli Roger , Müller Cristina
Published: June 2020

The concept of using ibuprofen as an albumin-binding entity was recently demonstrated by the development of [177Lu]Lu-Ibu-PSMA-01. In the present study, we designed a novel ibuprofen-containing radioligand (Ibu-PSMA-02) with subtle structural changes regarding the linker entity in order to investigate a potential impact on the in vitro and in vivo properties. Ibu-PSMA-02 was prepared using solid-phase synthesis techniques and labeled with lutetium-177. [177Lu]Lu-Ibu-PSMA-02 was evaluated in vitro with regard to its plasma protein-binding properties, PSMA affinity and uptake into PSMA-expressing PC-3 PIP tumor cells. The tissue distribution profile of [177Lu]Lu-Ibu-PSMA-02 was assessed in tumor-bearing mice and dose estimations were performed. The in vitro characteristics of [177Lu]Lu-Ibu-PSMA-02 were similar to those previously obtained for [177Lu]Lu-Ibu-PSMA-01 with respect to plasma protein-binding, PSMA affinity and tumor cell uptake. The in vivo studies revealed, however, an unprecedentedly high uptake of [177Lu]Lu-Ibu-PSMA-02 in PC-3 PIP tumors, resulting in an increased absorbed tumor dose of 7.7 Gy/MBq as compared to 5.1 Gy/MBq calculated for [177Lu]Lu-Ibu-PSMA-01. As a consequence of the high tumor accumulation, [177Lu]Lu-Ibu-PSMA-02 showed higher tumor-to-background ratios than [177Lu]Lu-Ibu-PSMA-01. This study exemplified that smallest structural changes in the linker entity of PSMA radioligands may have a significant impact on their pharmacokinetic profiles and, thus, may be applied as a means for ligand design optimization.
1-Hydroxyanthraquinones Containing Aryl Substituents as Potent and Selective Anticancer Agents
Authors: Sirazhetdinova Nafisa S. , Savelyev Victor A. , Frolova Tatyana S. , Baev Dmitry S. , Klimenko Lyubov S. , Chernikov Ivan V. , Oleshko Olga S. , Sarojan Teresa A. , Pokrovskii Andrey G. , Shults Elvira E.
Published: June 2020

A series of 1,2-, 1,4-disubstituted or 1,2,4-trisubstituted anthraquinone-based compounds was designed, synthesized, characterized and biologically evaluated for anticancer efficacy. 2- or 4-arylated 1-hydroxy-9,10-antraquinones (anthracene-9,10-diones) were prepared by Suzuki–Miyaura cross-coupling reaction of 1-hydroxy-2-bromoanthraquinone, 1-hydroxy-4-iodoanthraquinone or 1-hydroxy-2,4-dibromoanthraquinone with arylboronic acids. The cross-coupling reaction of 2,4-dibromo-9,10-anthraquinone with arylboronic acids provide a convenient approach to 2,4-bis arylated 1-hydroxyanthraquinones with a variety of aryl substituent in the 2 and 4 position. The cytotoxicity of new anthraquinone derivatives was evaluated using the conventional MTT assays. The data revealed that six of the aryl substituted compounds among the entire series 3, 15, 16, 25, 27, 28 were comparable potent with the commercially available reference drug doxorubicin on the human glioblastoma cells SNB-19, prostate cancer DU-145 or breast cancer cells MDA-MB-231 and were relatively safe towards human telomerase (h-TERT)immortalized lung fibroblasts cells. The results suggested that the in vitro antitumor activity of synthesized 2-aryl, 4-aryl- and 2,4-diaryl substituted 1-hydroxyanthraquinones depends on the nature of the substituent within the cyclic backbone. Docking interaction of 2-, 4-substituted and 2,4-disubstituted 1-hydroxyanthraquinones indicates intercalative mode of binding of compounds with DNA topoisomerase. The interaction with the DNA of 4-aryl-13, 15, 16 and 4-(furan-3-yl)-23 1-hydroxyanthraquinones was experimentally confirmed through a change in electroforetic mobility. Further experiments with 1-hydroxy-4-phenyl-anthraquinone 13 demonstrated that the compound induced cell cycle arrest at sub-G1 phase in DU-145 cells in the concentration 1.1 μM, which is probably achieved by inducing apoptosis. 4-Arylsubstituted 1-hydroxyanthraquinones 13 and 16 induced the enhancement of DNA synthesis on SNB19 cell lines.
Biobased Cryogels from Enzymatically Oxidized Starch: Functionalized Materials as Carriers of Active Molecules
Authors: Boccia Antonella Caterina , Scavia Guido , Schizzi Ilaria , Conzatti Lucia
Published: June 2020

Starch recovered from an agrifood waste, pea pods, was enzymatically modified and used to prepare cryogels applied as drug carriers. The enzymatic modification of starch was performed using the laccase/(2,2,6,6-tetramethylpiperidin-1-yl)oxyl TEMPO system, at a variable molar ratio. The characterization of the ensuing starches by solution NMR spectroscopy showed partial conversion of the primary hydroxyl groups versus aldehyde and carboxyl groups and successive creation of hemiacetal and ester bonds. Enzymatically modified starch after simple freezing and lyophilization process provided stable and compact cryogels with a morphology characterized by irregular pores, as determined by atomic force (AFM) and scanning electron microscopy (SEM). The application of cryogels as carriers of active molecules was successfully evaluated by following two different approaches of loading with drugs: a) as loaded sponge, by adsorption of drug from the liquid phase; and b) as dry-loaded cryogel, from a dehydration step added to loaded cryogel from route (a). The efficiency of the two routes was studied and compared by determining the drug release profile by proton NMR studies over time. Preliminary results demonstrated that cryogels from modified starch are good candidates to act as drug delivery systems due to their stability and prolonged residence times of loaded molecules, opening promising applications in biomedical and food packaging scenarios.
Glycyrrhetinic Acid Liposomes and Hyalurosomes on Spanish Broom, Flax, and Hemp Dressings to Heal Skin Wounds
Authors: Abruzzo Angela , Cappadone Concettina , Farruggia Giovanna , Luppi Barbara , Bigucci Federica , Cerchiara Teresa
Published: June 2020

The focus of this work was to prepare Spanish Broom, flax, and hemp dressings impregnated with glycyrrhetinic acid (GA) liposomes or hyalurosomes to promote the healing process and protect the skin wounds. Vesicles were prepared by the film hydration method and characterized in terms of size, particle size distribution, ζ potential, encapsulation efficiency, in vitro release, and biocompatibility on 3T3 fibroblasts. Loaded liposomes and hyalurosomes showed nanometric size (355 ± 19 nm and 424 ± 32 nm, respectively), good size distribution (lower than 0.3), and appropriate encapsulation efficiency (58.62 ± 3.25% and 59.22 ± 8.18%, respectively). Hyalurosomes showed good stability during the storage period, which can be correlated to the negative ζ potential, and allowed a fast and complete release of GA. Preliminary biological studies revealed that both kinds of loaded vesicles were not cytotoxic and that hyalurosomes could exert a slight stimulating effect on fibroblast proliferation. Finally, in vitro release studies from the different dressings impregnated with the loaded vesicles demonstrated that a high amount of GA could be reached at the wound site after 60 min from application. In conclusion, the results suggested that the developed dressings, especially those impregnated with hyalurosomes, can be efficiently used to promote the healing process.
New Morphiceptin Peptidomimetic Incorporating (1S,2R,3S,4S,5R)-2-Amino-3,4,5-trihydroxycyclopen-tane-1-carboxylic acid: Synthesis and Structural Study
Authors: Soengas Raquel , Lorca Marcos , Pampín Begoña , Sánchez-Pedregal Víctor M. , Estévez Ramón J. , Estévez Juan C.
Published: June 2020

We present the synthesis and structural study of a new peptidomimetic of morphiceptin, which can formally be considered as the result of the replacement of the central proline residue of this natural analgesic drug with a subunit of (1S,2R,3S,4S,5R)-2-amino-3,4,5-trihydroxycyclopentane-1-carboxylic acid, previously obtained from L-idose. An optimized synthesis of this trihydroxylated cispentacin derivative is also reported. Molecular docking calculations on the target receptor support a favorable role of the hydroxy substituents of the non-natural β-amino acid incorporated into the peptidomimetic.
Thermal Transport Investigation in Magneto-Radiative GO-MoS2/H2O-C2H6O2 Hybrid Nanofluid Subject to Cattaneo–Christov Model
Authors: Mohyud-Din Syed Tauseef , Adnan  , Khan Umar , Ahmed Naveed , Khan Ilyas , Abdeljawad T. , Nisar Kottakkaran Sooppy
Published: June 2020

Currently, thermal investigation in hybrid colloidal liquids is noteworthy. It has applications in medical sciences, drug delivery, computer chips, electronics, the paint industry, mechanical engineering and to perceive the cancer cell in human body and many more. Therefore, the study is carried out for 3D magnetized hybrid nanofluid by plugging the novel Cattaneo–Christov model and thermal radiations. The dimensionless version of the model is successfully handled via an analytical technique. From the reported analysis, it is examined that Graphene Oxide-molybdenum disulfide/C2H6O2-H2O has better heat transport characteristics and is therefore reliable for industrial and technological purposes. The temperature of Graphene Oxide GO-molybdenum disulfide/C2H6O2-H2O enhances in the presence of thermal relaxation parameter and radiative effects. Also, it is noted that rotational velocity of the hybrid nanofluid rises for stronger magnetic parameter effects. Moreover, prevailed behavior of thermal conductivity of GO-molybdenum disulfide/C2H6O2-H2O is detected which shows that hybrid nanofluids are a better conductor as compared to that of a regular nanofluid.
Discovery of New Schiff Bases Tethered Pyrazole Moiety: Design, Synthesis, Biological Evaluation, and Molecular Docking Study as Dual Targeting DHFR/DNA Gyrase Inhibitors with Immunomodulatory Activity
Authors: Hassan Ashraf S. , Askar Ahmed A. , Naglah Ahmed M. , Almehizia Abdulrahman A. , Ragab Ahmed
Published: June 2020

A series of Bis-pyrazole Schiff bases (6a–d and 7a–d) and mono-pyrazole Schiff bases (8a–d and 9a–d) were designed and synthesized through the reaction of 5-aminopyrazoles 1a–d with aldehydes 2–5 using mild reaction condition with a good yield percentage. The chemical structure of newly formed Schiff bases tethered pyrazole core was confirmed based on spectral and experimental data. All the newly formed pyrazole Schiff bases were evaluated against eight pathogens (Gram-positive, Gram-negative, and fungi). The result exhibited that, most of them have good and broad activities. Among those, only six Schiff bases (6b, 7b, 7c, 8a, 8d, and 9b) displayed MIC values (0.97–62.5 µg/mL) compared to Tetracycline (15.62–62.5 µg/mL) and Amphotericin B (15.62–31.25 µg/mL), MBC values (1.94–87.5 µg/mL) and selectivity to tumor cell than normal cells. Immunomodulatory activities showed that the promising Schiff bases increase the immunomodulator effect of defense cell and the Schiff base 8a is the highest one by (Intra. killing activity = 136.5 ± 0.3%) having a pyrazole moiety as well as amide function (O=C-NH2) and piperidinyl core. Furthermore, the most potent one exhibited broad activity depending on both MIC and MBC values. Moreover, to study the mechanism of these pyrazole Schiff bases, two active Schiff bases 8a and 9b from six derivatives were introduced to study the enzyme assay as dihydrofolate reductase (DHFR) on E. coli organism and DNA gyrase with two different organisms, S. aureus and B. subtilis, to determine the inhibitory activities with lower values in the case of DNA gyrase (8a and 9b) or nearly as DHFR compound 9b, while pyrazole 8a showed excellent inhibitory against all enzyme assay. The molecular docking study against dihydrofolate reductase and DNA gyrase were performed to study the binding between active site in the pocket with the two Schiff bases (8a and 9b) that exhibited good binding affinity with different bond types as H-bonding, aren-aren, and arene-cation interaction as well as study the physicochemical and pharmacokinetic properties of the two active Schiff bases 8a and 9b.
Inversion Method Characterization of Graphene-Based Coordination Absorbers Incorporating Periodically Patterned Metal Ring Metasurfaces
Authors: Bao Zhiyu , Tang Yang , Hu Zheng-Da , Zhang Chengliang , Balmakou Aliaksei , Khakhomov Sergei , Semchenko Igor , Wang Jicheng
Published: June 2020

In this paper, we propose a tunable coordinated multi-band absorber that combines graphene with metal–dielectric–metal structures for the realization of multiple toward perfect absorption. The parametric inversion method is used to extract the equivalent impedance and explain the phenomena of multiple-peak absorption. With the change of the Fermi level, equivalent impedances were extracted, and the peculiarities of the individual multiple absorption peaks to change were determined. By changing the structure parameters of gold rings, we obtain either multiple narrow-band absorption peaks or a broadband absorption peak, with the bandwidth of 0.8 μm where the absorptance is near 100%. Therefore, our results provide new insights into the development of tunable multi-band absorbers and broadband absorbers that can be applied to terahertz imaging in high-performance coordinate sensors and other promising optoelectronic devices.
Far Eastern Scarlet-Like Fever is a Special Clinical and Epidemic Manifestation of Yersinia pseudotuberculosis Infection in Russia
Authors: Somova Larisa M. , Antonenko Fedor F. , Timchenko Nelly F. , Lyapun Irina N.
Published: June 2020

Pseudotuberculosis in humans until the 1950s was found in different countries of the world as a rare sporadic disease that occurred in the form of acute appendicitis and mesenteric lymphadenitis. In Russia and Japan, the Yersinia pseudotuberculosis (Y. pseudotuberculosis) infection often causes outbreaks of the disease with serious systemic inflammatory symptoms, and this variant of the disease has been known since 1959 as Far Eastern Scarlet-like Fever (FESLF). Russian researchers have proven that the FESLF pathogen is associated with a concrete clonal line of Y. pseudotuberculosis, characterized by a specific plasmid profile (pVM82, pYV 48 MDa), sequence (2ST) and yadA gene allele (1st allele). This review summarized the most important achievements in the study of FESLF since its discovery in the Far East. It has been established that the FESLF causative agent is characterized by a unique phenomenon of psychrophilicity, which consists of its ability to reproduce in the environment with its biologically low and variable temperature (4–12 °C), at which the pathogen multiplies and accumulates while maintaining or increasing its virulence, which ensures the emergence and development of the epidemic process. The key genetic and biochemical mechanisms of Y. pseudotuberculosis adaptation to changing environmental conditions were characterized, and the morphological manifestations of the adaptive variability of these bacteria in different conditions of their habitat were revealed. The main features of the pathogenesis and morphogenesis of FESLF, including those associated with the Y. pseudotuberculosis toxigenicity, were presented. The pathogenetic value of the plasmid PVM82, found only in the FESLF pathogen, was shown.
Enhanced Production of Bryonolic Acid in Trichosanthes cucumerina L. (Thai Cultivar) Cell Cultures by Elicitors and Their Biological Activities
Authors: Lertphadungkit Pornpatsorn , Suksiriworapong Jiraphong , Satitpatipan Veena , Sirikantaramas Supaart , Wongrakpanich Amaraporn , Bunsupa Somnuk
Published: June 2020

Bryonolic acid is a triterpenoid compound found in cucurbitaceous roots. Due to its biological activities, this compound gets more attention to improve production. Herein, we carried out efficient ways with high bryonolic acid productions from Trichosanthes cucumerina L., a Thai medicinal plant utilizing plant cell cultures. The results showed that calli (24.65 ± 1.97 mg/g dry weight) and cell suspensions (15.69 ± 0.78 mg/g dry weight) exhibited the highest bryonolic acid productions compared with natural roots (approximately 2 mg/g dry weight). In the presence of three elicitors (methyl jasmonate, yeast extract, and chitosan), cell suspensions treated with 1 mg/mL of chitosan for eight days led to higher bryonolic acid contents (23.56 ± 1.68 mg/g dry weight). Interestingly, cell culture and root extracts with high bryonolic acid contents resulted in significantly higher percent cell viabilities than those observed under control (1% v/v DMSO) treatment in Saos-2 and MCF-7 cells. The present study indicated that T. cucumerina L. cell cultures are alternative and efficient to produce the biologically important secondary metabolite.
A Feed-Forward Back Propagation Neural Network Approach to Predict the Life Condition of Crude Oil Pipeline
Authors: Shaik Nagoor Basha , Pedapati Srinivasa Rao , Taqvi Syed Ali Ammar , Othman A. R. , Dzubir Faizul Azly Abd
Published: June 2020

Pipelines are like a lifeline that is vital to a nation’s economic sustainability; as such, pipelines need to be monitored to optimize their performance as well as reduce the product losses incurred in the transportation of petroleum chemicals. A significant number of pipes would be underground; it is of immediate concern to identify and analyse the level of corrosion and assess the quality of a pipe. Therefore, this study intends to present the development of an intelligent model that predicts the condition of crude oil pipeline cantered on specific factors such as metal loss anomalies (over length, width and depth), wall thickness, weld anomalies and pressure flow. The model is developed using Feed-Forward Back Propagation Network (FFBPN) based on historical inspection data from oil and gas fields. The model was trained using the Levenberg-Marquardt algorithm by changing the number of hidden neurons to achieve promising results in terms of maximum Coefficient of determination (R2) value and minimum Mean Squared Error (MSE). It was identified that a strong R2 value depends on the number of hidden neurons. The model developed with 16 hidden neurons accurately predicted the Estimated Repair Factor (ERF) value with an R2 value of 0.9998. The remaining useful life (RUL) of a pipeline is estimated based on the metal loss growth rate calculations. The deterioration profiles of considered factors are generated to identify the individual impact on pipeline condition. The proposed FFBPN was validated with other published models for its robustness and it was found that FFBPN performed better than the previous approaches. The deterioration curves were generated and it was found that pressure has major negative affect on pipeline condition and weld girth has a minor negative affect on pipeline condition. This study can help petroleum and natural gas industrial operators assess the life condition of existing pipelines and thus enhances their inspection and rehabilitation forecasting.
Disjoint Spanning Tree Based Reliability Evaluation of Wireless Sensor Network
Authors: Lata Sonam , Mehfuz Shabana , Urooj Shabana , Ali Asmaa , Nasser Nidal
Published: June 2020

Wireless sensor networks (WSNs) are becoming very common in numerous manufacturing industries; especially where it is difficult to connect a sensor to a sink. This is an evolving issue for researchers attempting to contribute to the proliferation of WSNs. Monitoring a WSN depends on the type of collective data the sensor nodes have acquired. It is necessary to quantify the performance of these networks with the help of network reliability measures to ensure the stable operation of WSNs. Reliability plays a key role in the efficacy of any large-scale application of WSNs. The communication reliability in a wireless sensor network is an influential parameter for enhancing network performance for secure, desirable, and successful communication. The reliability of WSNs must incorporate the design variables, coverage, lifetime, and connectivity into consideration; however, connectivity is the most important factor, especially in a harsh environment on a large scale. The proposed algorithm is a one-step approach, which starts with the recognition of a specific spanning tree only. It utilizes all other disjoint spanning trees, which are generated directly in a simple manner and consume less computation time and memory. A binary decision illustration is presented for the enumeration of K-coverage communication reliability. In this paper, the issue of computing minimum spanning trees was addressed and it is a pertinent method for further evaluating reliability for WSNs. This paper inspects the reliability of WSNs and proposes a method for evaluating the flow-oriented reliability of WSNs. Further, a modified approach for the sum-of-disjoint products to determine the reliability of WSN from the enumerated minimal spanning trees is proposed. The proposed algorithm when implemented for different sizes of WSNs demonstrates its applicability to WSNs of various scales. The proposed methodology is less complex and more efficient in terms of reliability.
Exploiting the RSSI Long-Term Data of a WSN for the RF Channel Modeling in EPS Environments
Authors: Antayhua Roddy A. R. , Pereira Maicon D. , Fernandes Nestor C. , Rangel de Sousa Fernando
Published: June 2020

In this paper, we propose a methodology to use the received signal strength indicator (RSSI) available by the protocol stack of an installed Wireless Sensor Network (WSN) at an electric-power-system environment (EPS) as a tool for obtaining the characteristic of its communication channel. Thereby, it is possible to optimize the settings and configuration of the network after its deployment, which is usually run empirically without any previous knowledge of the channel. A study case of a hydroelectric power plant is presented, where measurements recorded over a two-month period were analyzed and treated to obtain the large-scale characteristics of the radiofrequency channel at 2.4 GHz. In addition, we showed that instantaneous RSSI data can also be used to detect specific issues in the network, such as repetitive patterns in the transmitted power level of the nodes, and information about its environment, such as the presence of external sources of electromagnetic interference. As a result, we demonstrate the practical use of the RSSI long-term data generated by the WSN for its own performance optimization and the detection of particular events in an EPS or any similar industrial environment.
Experimental Study of Split Grouting Reinforcement Mechanism in Filling Medium and Effect Evaluation
Authors: Niu Jiandong , Li Zewei , Gu Weiheng , Chen Kang
Published: June 2020

In view of the deficiency of the split grouting theory for the filling area, a 3D simulated grouting test system was designed to explore the slurry diffusion law, reinforcement mechanism of split grouting in a filling soil, and effect of grouting reinforcement. The test system included an experiment bench system, grouting system, and information monitoring system, using which experimental research on split grouting in a filling soil was conducted. The grouting model experiment procedure was introduced first, following which the diffusion rule of slurry in the filling medium and the reinforcement mechanism of split grouting were analyzed according to the properties and distribution characteristics of grouting veins after grouting reinforcement. Finally, a uniaxial compression test, light dynamic contact test, permeability test, and laboratory geotechnical test were conducted on the soil before and after grouting. The relationship between the zoning characteristics of different properties of veins and the mechanical properties of filling soil were discussed. The results showed that there were three types of grouting veins: trunk grouting, branch grouting, and permeable grouting. The injected soil body was strengthened by the three-stage grouting vein network of the mentioned vein types and the compaction between soils. After the grouting, the uniaxial compressive strength of the filling soil increased by an average of 186%, and the permeability coefficient decreased by an average of 47 times. The cohesion and internal friction angle increased by 45.3% and 44.9%, respectively. Additionally, density, water content, and other indicators of filling were improved. The bearing characteristics reflected by a dynamic contact test were consistent with the distribution of grouting veins. The research results offer significant guidance for the reinforcement mechanism of split grouting and the evaluation of the grouting effect.
Anomaly Detection Trusted Hardware Sensors for Critical Infrastructure Legacy Devices
Authors: Fournaris Apostolos P. , Dimopoulos Charis , Lampropoulos Konstantinos , Koufopavlou Odysseas
Published: June 2020

Critical infrastructures and associated real time Informational systems need some security protection mechanisms that will be able to detect and respond to possible attacks. For this reason, Anomaly Detection Systems (ADS), as part of a Security Information and Event Management (SIEM) system, are needed for constantly monitoring and identifying potential threats inside an Information Technology (IT) system. Typically, ADS collect information from various sources within a CI system using security sensors or agents and correlate that information so as to identify anomaly events. Such sensors though in a CI setting (factories, power plants, remote locations) may be placed in open areas and left unattended, thus becoming targets themselves of security attacks. They can be tampering and malicious manipulated so that they provide false data that may lead an ADS or SIEM system to falsely comprehend the CI current security status. In this paper, we describe existing approaches on security monitoring in critical infrastructures and focus on how to collect security sensor–agent information in a secure and trusted way. We then introduce the concept of hardware assisted security sensor information collection that improves the level of trust (by hardware means) and also increases the responsiveness of the sensor. Thus, we propose a Hardware Security Token (HST) that when connected to a CI host, it acts as a secure anchor for security agent information collection. We describe the HST functionality, its association with a host device, its expected role and its log monitoring mechanism. We also provide information on how security can be established between the host device and the HST. Then, we introduce and describe the necessary host components that need to be established in order to guarantee a high security level and correct HST functionality. We also provide a realization–implementation of the HST overall concept in a FPGA SoC evaluation board and describe how the HST implementation can be controlled. In addition, in the paper, two case studies where the HST has been used in practice and its functionality have been validated (one case study on a real critical infrastructure test site and another where a critical industrial infrastructure was emulated in our lab) are described. Finally, results taken from these two case studies are presented, showing actual measurements for the in-field HST usage.