bluuebunny/crossref_metadata_2025 huggingface dataset:
N-(3-Cyano-4,5,6,7-tetrahydrobenzothiophen-2-yl)-2-[[5-[(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)amino]-1,3,4-thiadiazol-2-yl]sulfanyl]acetamide
Authors: Holota Serhii , Yushyn Ihor , Khyluk Dmytro , Vynnytska Renata , Lesyk Roman
Published: May 2021

The small pyrazolone-bearing molecules attract attention and are widely explored in drug design as pharmacological agents. The new pyrazolone-thiadiazole hybrid molecule N-(3-cyano-4,5,6,7-tetrahydrobenzothiophen-2-yl)-2-[[5-[(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)amino]-1,3,4-thiadiazol-2-yl]sulfanyl]acetamide (3) has been synthesized following a two-stage protocol using simple, convenient transformations and cheap, commercially available reagents. The compound’s structure was confirmed using 1H, 13C nuclear magnetic resonance (NMR), and liquid chromatography–mass spectrometry (LC–MS) spectra. The anti-inflammatory potency of 3 was evaluated in silico using molecular docking. The docking studies results suggest that title compound 3 is of great interest for further structure optimization and in-depth studies as a possible 5-lipoxygenase (5-LOX) inhibitor.
Characteristics of Entrained Air Voids in Hardened Concrete with the Method of Digital Image Analysis Coupled with Schwartz-Saltykov Conversion
Authors: Ojala Teemu , Chen Yanjuan , Punkki Jouni , Al-Neshawy Fahim
Published: May 2021

This paper presents the characteristics of air void systems in hardened concrete with the method of digital image analysis (DIA) coupled with Schwartz-Saltykov (SS) conversion. The results indicate that the DIA method coupled with SS conversion estimates the air content with more accuracy than it would without SS conversion; the correlation between air content obtained from the DIA method, and that from the thin section (TS) method is as good as the correlation observed between the pressure saturation (PS) method and the TS method. It was also found that the DIA method shows a better correlation with the TS method when the spacing factor without SS conversion is considered, while both methods show poor correlations when the corresponding specific surface is considered. In addition, it indicates that the peak of three-dimensional size distribution (3-DSD) of air voids after SS conversion falls in smaller voids, and 3-DSD of air voids shifts to a narrow size range, in comparison with the 2-DSD without SS conversion; the shape of the 3-DSD air voids remains constant irrespective of the class widths. Increasing the number of classes can minimise the standard deviation in the estimation, however, it also results in a leap in voids volume density, which will influence the estimation of air content.
Blood Particulate Analogue Fluids: A Review
Authors: Sadek Samir Hassan , Rubio Manuel , Lima Rui , Vega Emilio José
Published: May 2021

Microfluidics has proven to be an extraordinary working platform to mimic and study blood flow phenomena and the dynamics of components of the human microcirculatory system. However, the use of real blood increases the complexity to perform these kinds of in vitro blood experiments due to diverse problems such as coagulation, sample storage, and handling problems. For this reason, interest in the development of fluids with rheological properties similar to those of real blood has grown over the last years. The inclusion of microparticles in blood analogue fluids is essential to reproduce multiphase effects taking place in a microcirculatory system, such as the cell-free layer (CFL) and Fähraeus–Lindqvist effect. In this review, we summarize the progress made in the last twenty years. Size, shape, mechanical properties, and even biological functionalities of microparticles produced/used to mimic red blood cells (RBCs) are critically exposed and analyzed. The methods developed to fabricate these RBC templates are also shown. The dynamic flow/rheology of blood particulate analogue fluids proposed in the literature (with different particle concentrations, in most of the cases, relatively low) is shown and discussed in-depth. Although there have been many advances, the development of a reliable blood particulate analogue fluid, with around 45% by volume of microparticles, continues to be a big challenge.
Hot Deformation Behavior and Processing Maps of a New Ti-6Al-2Nb-2Zr-0.4B Titanium Alloy
Authors: Yang Zhijun , Yu Weixin , Lang Shaoting , Wei Junyi , Wang Guanglong , Ding Peng
Published: May 2021

The hot deformation behaviors of a new Ti-6Al-2Nb-2Zr-0.4B titanium alloy in the strain rate range 0.01–10.0 s−1 and temperature range 850–1060 °C were evaluated using hot compressing testing on a Gleeble-3800 simulator at 60% of deformation degree. The flow stress characteristics of the alloy were analyzed according to the true stress–strain curve. The constitutive equation was established to describe the change of deformation temperature and flow stress with strain rate. The thermal deformation activation energy Q was equal to 551.7 kJ/mol. The constitutive equation was ε ˙=e54.41[sinh (0.01σ)]2.35exp(−551.7/RT). On the basis of the dynamic material model and the instability criterion, the processing maps were established at the strain of 0.5. The experimental results revealed that in the (α + β) region deformation, the power dissipation rate reached 53% in the range of 0.01–0.05 s−1 and temperature range of 920–980 °C, and the deformation mechanism was dynamic recovery. In the β region deformation, the power dissipation rate reached 48% in the range of 0.01–0.1 s−1 and temperature range of 1010–1040 °C, and the deformation mechanism involved dynamic recovery and dynamic recrystallization.
Effects of Amorphous Poly Alpha Olefin (APAO) and Polyphosphoric Acid (PPA) on the Rheological Properties, Compatibility and Stability of Asphalt Binder
Authors: Pei Xiaoguang , Fan Weiyu
Published: May 2021

High production costs and poor storage stability have become important constraints in the manufacture of modified asphalt binder. To simplify the production process and reduce the production cost, amorphous poly alpha olefin (APAO) and polyphosphoric acid (PPA) were applied to prepare highly stable modified asphalt binder. The influence of APAO/PPA on the temperature sensitivity, rheological property, storage stability, compatibility and microstructure of neat binder were studied by rotational viscosity (RV), dynamic shear rheometer (DSR), bending beam rheometer (BBR) and Fourier transform infrared (FTIR) spectroscopy. The results show that the incorporation of APAO/PPA reduced the temperature sensitivity of neat binder. The combined effect of APAO/PPA contributed to the improvement in deformation resistance, which was evidenced by the increase in failure temperature and percent recovery. However, the compound modification of APAO/PPA decreased the binder’s low-temperature performance. APAO strengthened the fatigue resistance of the binder, while PPA reduced the anti-fatigue performance. Composite modified asphalt binder with superior storage stability could be prepared, which was confirmed by the desired Cole–Cole plots and fluorescence imaging. Furthermore, chemical and physical reactions occurred during the APAO/PPA modification process. Overall, 2 wt.% (weight percentage) APAO and 1.5 wt.% PPA are recommended for the production of modified asphalt binder with remarkable rheological performance and storage stability.
Fabrication of Polyurethane/Polylactide (PU/PLDL) Nanofibers Using Electrospinning Method
Authors: Lech Marta , Mastalska-Popławska Joanna , Laska Jadwiga
Published: May 2021

Polylactide and aliphatic polyurethane are biodegradable synthetic polymers which are broadly used as biomaterials in regenerative medicine for implants and scaffolds for tissue engineering. In this paper, the detailed studies of the fabrication of the electrospun fibers of polyurethane/polylactide mixtures were described. The influence of the used solvent (dimethylformamide (DMF)) and diluents (acetone and dichloromethane (DCM)) on the rheological parameters and electrospinning of the described mixtures was examined. Rheological studies showed that polyure-thane/polylactide mixtures have mostly non-Newtonian character, strongly influenced by the diluent. Solutions containing 50 wt.% or more of polyurethane became less viscous after the addition of DCM or acetone, whereas those with bigger amount of polylactide showed higher viscosity after the addition of DCM and lower viscosity after the addition of acetone. Optimized electrospinning process has been elaborated. Fibers with diameters from 250 nm up to 1 µm have been produced and compared. Pure acetone worsened the electrospinning process, but the more DCM was in the mixture, the thinner and more aligned fibers were produced.
Effect of Residual Trace Amounts of Fe and Al in Li[Ni1/3Mn1/3Co1/3]O2 Cathode Active Material for the Sustainable Recycling of Lithium-Ion Batteries
Authors: Jeong Seongdeock , Park Sanghyuk , Beak Mincheol , Park Jangho , Sohn Jeong-Soo , Kwon Kyungjung
Published: May 2021

As the explosive growth of the electric vehicle market leads to an increase in spent lithium-ion batteries (LIBs), the disposal of LIBs has also made headlines. In this study, we synthesized the cathode active materials Li[Ni1/3Mn1/3Co1/3]O2 (NMC) and Li[Ni1/3Mn1/3Co1/3Fe0.0005Al0.0005]O2 (NMCFA) via hydroxide co-precipitation and calcination processes, which simulate the resynthesis of NMC in leachate containing trace amounts of iron and aluminum from spent LIBs. The effects of iron and aluminum on the physicochemical and electrochemical properties were investigated and compared with NMC. Trace amounts of iron and aluminum do not affect the morphology, the formation of O3-type layered structures, or the redox peak. On the other hand, the rate capability of NMCFA shows high discharge capacities at 7 C (110 mAh g−1) and 10 C (74 mAh g−1), comparable to the values for NMC at 5 C (111 mAh g−1) and 7 C (79 mAh g−1), respectively, due to the widened interslab thickness of NMCFA which facilitates the movement of lithium ions in a 2D channel. Therefore, iron and aluminum, which are usually considered as impurities in the recycling of LIBs, could be used as doping elements for enhancing the electrochemical performance of resynthesized cathode active materials.
Microstructure, Texture and Mechanical Properties in Aluminum Produced by Friction-Assisted Lateral Extrusion
Authors: Vu Viet Q. , Toth Laszlo S. , Beygelzimer Yan , Zhao Yajun
Published: May 2021

The Friction-Assisted Lateral Extrusion Process (FALEP) is a severe plastic deformation (SPD) technique for producing metal sheets from bulk metal or powder in one single deformation step at room temperature. In the present work, aluminum Al-1050 was deformed by FALEP. Then, its microstructure was examined by EBSD; the crystallographic texture by X-ray; material strength, ductility, and the Lankford parameter by tensile testing; the latter also by polycrystal plasticity simulations. It is shown that the microstructure was highly refined, with the grain size reduced more than 160 times down to 600 nm under the imposed shear strain of 20. The obtained texture was a characteristic simple shear texture with a shear plane nearly parallel to the plane of the sheet. The yield and ultimate strengths increased by about 10 times and three times, respectively. The Lankford parameter was 1.28, which is very high for aluminum, and due to the specific shear texture, unusual in a sheet. All these exceptional characteristics of Al-1050 were obtained thanks to the efficiency of the FALEP SPD process, which is a promising candidate for industrial applications.
Development of Ammonia Selectively Permeable Zeolite Membrane for Sensor in Sewer System
Authors: Inami Hisao , Abe Chie , Hasegawa Yasuhisa
Published: May 2021

Ammonia (NH3) and hydrogen sulfide (H2S) are hazardous and odorous gases. A special device that is not affected by other gases is necessary so that it can detect such gases. Zeolite membranes can separate the desired component selectively by molecular sieving and selective adsorption. LTA-, MFI-, and FAU-type zeolite membranes were prepared in this study, and the permeation and separation performances were determined for the ternary mixture of NH3, H2S, and N2 to develop an NH3 selectively permeable membrane. Although the separation factors of NH3 were high enough for the LTA-type zeolite membrane, the NH3 permeance was the lowest among the three membranes. In contrast, the FAU-type zeolite membrane with Si/Al = 1.35 showed a high enough NH3 permeance and a NH3/N2 separation factor. The membrane modification and varying the membrane composition were carried out to reduce the H2S permeance. As a result, the H2S permeance could be decreased by modification with silane coupling agents, and a separation factor of NH3 toward H2S of over 3000 was achieved.
Dynamic Modeling of Fouling in Reverse Osmosis Membranes
Authors: Ling Bowen , Xie Peng , Ladner David , Battiato Ilenia
Published: May 2021

During reverse osmosis (RO) membrane filtration, performance is dramatically affected by fouling, which concurrently decreases the permeate flux while increasing the energy required to operate the system. Comprehensive design and optimization of RO systems are best served by an understanding of the coupling between membrane shape, local flow field, and fouling; however, current studies focus exclusively on simplified steady-state models that ignore the dynamic coupling between fluid flow, solute transport, and foulant accumulation. We developed a customized solver (SUMs: Stanford University Membrane Solver) under the open source finite volume simulator OpenFOAM to solve transient Navier–Stokes, advection–diffusion, and adsorption–desorption equations for foulant accumulation. We implemented two permeate flux reduction models at the membrane boundary: the resistance-in-series (RIS) model and the effective-pressure-drop (EPD) model. The two models were validated against filtration experiments by comparing the equilibrium flux, pressure drop, and fouling pattern on the membrane. Both models not only predict macroscopic quantities (e.g., permeate flux and pressure drop) but also the fouling pattern developed on the membrane, with a good match with experimental results. Furthermore, the models capture the temporal evolution of foulant accumulation and its coupling with flux reduction.
Organic Nanobowls Modified Thin Film Composite Membrane for Enhanced Purification Performance toward Different Water Resources
Authors: Ou Changjin , Li Sisi , Wang Zhongyi , Qin Juan , Wang Qian , Liao Zhipeng , Li Jiansheng
Published: May 2021

The structure and composition of nanofillers have a significant influence on polyamide nanofiltration (NF) membranes. In this work, an asymmetric organic nanobowl containing a concave cavity was synthesized and incorporated into a polyamide layer to prepare thin film nanocomposite (TFN) membranes via an interfacial polymerization process. Benefiting from the hydrophilicity, hollow cavity and charge property of the compatible organic nanobowls, the separation performance of the developed TFN membrane was significantly improved. The corresponding water fluxes increased to 119.44 ± 5.56, 141.82 ± 3.24 and 130.27 ± 2.05 L/(m2·h) toward Na2SO4, MgCl2 and NaCl solutions, respectively, with higher rejections, compared with the control thin film composite (TFC) and commercial (CM) membranes. Besides this, the modified TFN membrane presented a satisfying purification performance toward tap water, municipal effluent and heavy metal wastewater. More importantly, a better antifouling property of the TFN membrane than TFC and CM membranes was achieved with the assistance of organic nanobowls. These results indicate that the separation performance of the TFN membrane can be elevated by the incorporation of organic nanobowls.
Effect of F16-Betulin Conjugate on Mitochondrial Membranes and Its Role in Cell Death Initiation
Authors: Dubinin Mikhail V. , Semenova Alena A. , Nedopekina Darya A. , Davletshin Eldar V. , Spivak Anna Yu. , Belosludtsev Konstantin N.
Published: May 2021

This work demonstrates the effects of a newly synthesized conjugate of the plant triterpenoid betulin and the penetrating cation F16 used for mitochondrial targeting. The resulting F16-betulin conjugate revealed a mitochondria-targeted effect, decreasing the mitochondrial potential and inducing superoxide overproduction in rat thymocytes in vitro. It has been suggested that this may cause the cytotoxic effect of the conjugate, which significantly exceeds the effectiveness of its precursors, betulin and F16. Using isolated rat liver mitochondria, we found that the F16-betulin conjugate has a surface-active effect on mitochondrial membranes, causing organelle aggregation. This effect of the derivative resulted in a dose-dependent decrease in mitochondrial transmembrane potential, as well as suppression of respiration and oxidative phosphorylation, especially in the case of nicotinamide adenine dinucleotide (NAD)-fueled organelles. In addition, the F16-betulin conjugate caused an increase in H2O2 generation by mitochondria fueled with glutamate and malate. These effects of the derivative can presumably be due to the powerful suppression of the redox activity of complex I of the mitochondrial electron transport chain. The paper discusses how the mitochondria-targeted effects of the F16-betulin conjugate may be related to its cytotoxic effects.
Influence of Additive Manufactured Stainless Steel Tool Electrode on Machinability of Beta Titanium Alloy
Authors: Shanmugam Ragavanantham , Ramoni Monsuru , Thangamani Geethapriyan , Thangaraj Muthuramalingam
Published: May 2021

Additive manufacturing technology provides a gateway to completely new horizons for producing a wide range of components, such as manufacturing, medicine, aerospace, automotive, and space explorations, especially in non-conventional manufacturing processes. The present study analyzes the influence of the additive manufactured tool in electrochemical micromachining (ECMM) on machining beta titanium alloy. The influence of different machining parameters, such as applied voltage, electrolytic concentration, and duty ratio on material removal rate (MRR), overcut, and circularity was also analyzed. It was inferred that the additive manufactured tool can produce better circularity and overcut than a bare tool due to its higher corrosion resistance and localization effect. The additive manufactured tool can remove more material owing to its strong atomic bond of metals and higher electrical conductivity.
3D Bioprinting of Model Tissues That Mimic the Tumor Microenvironment
Authors: Bojin Florina , Robu Andreea , Bejenariu Maria Iulia , Ordodi Valentin , Olteanu Emilian , Cean Ada , Popescu Roxana , Neagu Monica , Gavriliuc Oana , Neagu Adrian , Arjoca Stelian , Păunescu Virgil
Published: May 2021

The tumor microenvironment (TME) influences cancer progression. Therefore, engineered TME models are being developed for fundamental research and anti-cancer drug screening. This paper reports the biofabrication of 3D-printed avascular structures that recapitulate several features of the TME. The tumor is represented by a hydrogel droplet uniformly loaded with breast cancer cells (106 cells/mL); it is embedded in the same type of hydrogel containing primary cells—tumor-associated fibroblasts isolated from the peritumoral environment and peripheral blood mononuclear cells. Hoechst staining of cryosectioned tissue constructs demonstrated that cells remodeled the hydrogel and remained viable for weeks. Histological sections revealed heterotypic aggregates of malignant and peritumoral cells; moreover, the constituent cells proliferated in vitro. To investigate the interactions responsible for the experimentally observed cellular rearrangements, we built lattice models of the bioprinted constructs and simulated their evolution using Metropolis Monte Carlo methods. Although unable to replicate the complexity of the TME, the approach presented here enables the self-assembly and co-culture of several cell types of the TME. Further studies will evaluate whether the bioprinted constructs can evolve in vivo in animal models. If they become connected to the host vasculature, they may turn into a fully organized TME.
Design and Experimental Study of Space Continuous Robots Applied to Space Non-Cooperative Target Capture
Authors: Liu Yuwang , Wang Dongqi , Zhang Yongchao , Yuan Zhongqiu , Liu Jinguo , Yang Sheng , Yu Yi
Published: May 2021

Space capture actuators face problems such as insufficient flexibility and electrical components that are vulnerable to extreme space environments. To address these problems, a centralized-driven flexible continuous robot based on a multiple scissor mechanism units is proposed in this study. The continuous robot body is composed of two scissor mechanism units coupled in series, and the base container’s three motors to drive the robot. The two scissor mechanism units ensure a wide range of flexible operations and the light weight of the robot. The centralized drive with three motors not only reduces the number of driving sources, but also ensures temperature control and protection of electrical components in the space environment. The kinematics and dynamics of the robot are analyzed, and the workspace and deformation performance of the robot are verified through experiments. Compared with other continuous robots, the proposed continuous robot retains the characteristics of continuous robots in a wide range of flexible operations. At the same time, the configuration is light and a small number of driving sources are used, which is suitable for extreme temperatures, vacuum, radiation, and strict resource-constrained environments in space.
Response Enhancement of Pt–AlGaN/GaN HEMT Gas Sensors by Thin AlGaN Barrier with the Source-Connected Gate Configuration at High Temperature
Authors: Vuong Tuan-Anh , Cha Ho-Young , Kim Hyungtak
Published: May 2021

AlGaN/GaN HEMT hydrogen gas sensors were optimized by AlGaN barrier thickness in the gate-source connected configuration demonstrated high response and robust stability up to 500 °C. First, we found that the hydrogen sensing performance of a conventional normally-on HEMT-based sensor was enhanced when zero voltage was applied on the gate in comparison with a floating-gate condition due to a reduced level of the base current. In the next step, to take advantage of the response increase by VGS = 0 V, a new type of sensor with a source-connected gate (SCG) was fabricated to utilize the normally-on operation of the GaN HEMT sensor as a two-terminal device. AlGaN barrier thickness was thinned by the dry-etching process to gain higher transconductance at a zero-gate bias with the reduction of the distance from the 2DEG channel to the AlGaN surface, thereby significantly improve the hydrogen response. The SCG GaN sensor with an ultra-thin AlGaN barrier (9 nm) exhibited responses of 85% and 20% at 200 and 500 °C, respectively, onto 4%-hydrogen gas, which demonstrates a promising ability for harsh environment applications.
The Response of the Soil Microbiome to Contamination with Cadmium, Cobalt and Nickel in Soil Sown with Brassica napus
Authors: Boros-Lajszner Edyta , Wyszkowska Jadwiga , Borowik Agata , Kucharski Jan
Published: May 2021

Soil fertility is determined by biological diversity at all levels of life, from genes to entire biocenoses. The aim of this study was to evaluate bacterial diversity in soil contaminated with Cd2+, Co2+ and Ni2+ and sown with Brassica napus. This is an important consideration because soil-dwelling microorganisms support phytoremediation and minimize the adverse effects of heavy metals on the environment. Microbial counts, the influence (IFHM) of Cd2+, Co2+ and Ni2+ on microorganisms, the colony development (CD) index, the ecophysiological diversity (EP) index and genetic diversity of bacteria were determined under controlled conditions. Soil contamination with Cd2+, Co2+ and Ni2+ significantly influenced microbial diversity and increased the values of CD and EP indices. The tested heavy metals decreased the genetic diversity of bacteria, in particular in the phyla Actinobacteria and Proteobacteria. Bacteria of the genera Arthrobacter, Devosia, Kaistobacter, Paenibacillus, Phycicoccus, Rhodoplanes and Thermomonas were identified in both contaminated and non-contaminated soil. These bacteria are highly resistant to soil contamination with Cd2+, Co2+ and Ni2+.
Health Risks and Source Analysis of Heavy Metal Pollution from Dust in Tianshui, China
Authors: Tan Bo , Wang Hongwei , Wang Xinmin , Ma Chen , Zhou Jing , Dai Xinyan
Published: May 2021

The purpose of this study is to explore the degree and spatial distribution of dust heavy metal pollution in Tianshui City, the health risks, and the sources of heavy metals. The geoaccumulation index and health risk assessment are used to study pollution levels and human health risks, and Cu, Zn, and Pb pollution are found to be serious. The total exposure of children to dust and heavy metals is 8.329 × 10−3 mg·kg−1·d−1, which is 4.66 times that of adults. The effect of carcinogenic heavy metal exposure is more significant for adults than for children. The total non-carcinogenic risk quotient to children via multiple pathways is 2.1690, which is higher than that of adults. Children’s Pb non-carcinogenic risk quotient is 4.79 times that of adults, and children are more sensitive than adults to the health risks of Pb pollution. The GeoDetector and Unmix 6.0 models are used for source analysis, revealing that Zn, Pb, and As pollution originate primarily from urban transportation systems, V is sourced from soil-forming parent materials, and Mn, Ni, Cu, and Co arise from mixed sources. Therefore, the treatment of heavy metal pollution in cities needs to focus more on the urban transportation system.
Cannabinoids, Phenolics, Terpenes and Alkaloids of Cannabis
Authors: Radwan Mohamed M. , Chandra Suman , Gul Shahbaz , ElSohly Mahmoud A.
Published: May 2021

Cannabis sativa is one of the oldest medicinal plants in the world. It was introduced into western medicine during the early 19th century. It contains a complex mixture of secondary metabolites, including cannabinoids and non-cannabinoid-type constituents. More than 500 compounds have been reported from C. sativa, of which 125 cannabinoids have been isolated and/or identified as cannabinoids. Cannabinoids are C21 terpeno-phenolic compounds specific to Cannabis. The non-cannabinoid constituents include: non-cannabinoid phenols, flavonoids, terpenes, alkaloids and others. This review discusses the chemistry of the cannabinoids and major non-cannabinoid constituents (terpenes, non-cannabinoid phenolics, and alkaloids) with special emphasis on their chemical structures, methods of isolation, and identification.
Exploring the 2′-Hydroxy-Chalcone Framework for the Development of Dual Antioxidant and Soybean Lipoxygenase Inhibitory Agents
Authors: Kostopoulou Ioanna , Tzani Andromachi , Polyzos Nestor-Ioannis , Karadendrou Maria-Anna , Kritsi Eftichia , Pontiki Eleni , Liargkova Thalia , Hadjipavlou-Litina Dimitra , Zoumpoulakis Panagiotis , Detsi Anastasia
Published: May 2021

2′-hydroxy-chalcones are naturally occurring compounds with a wide array of bioactivity. In an effort to delineate the structural features that favor antioxidant and lipoxygenase (LOX) inhibitory activity, the design, synthesis, and bioactivity profile of a series of 2′-hydroxy-chalcones bearing diverse substituents on rings A and B, are presented. Among all the synthesized derivatives, chalcone 4b, bearing two hydroxyl substituents on ring B, was found to possess the best combined activity (82.4% DPPH radical scavenging ability, 82.3% inhibition of lipid peroxidation, and satisfactory LOX inhibition value (IC50 = 70 μM). Chalcone 3c, possessing a methoxymethylene substituent on ring A, and three methoxy groups on ring B, exhibited the most promising LOX inhibitory activity (IC50 = 45 μM). A combination of in silico techniques were utilized in an effort to explore the crucial binding characteristics of the most active compound 3c and its analogue 3b, to LOX. A common H-bond interaction pattern, orienting the hydroxyl and carbonyl groups of the aromatic ring A towards Asp768 and Asn128, respectively, was observed. Regarding the analogue 3c, the bulky (-OMOM) group does not seem to participate in a direct binding, but it induces an orientation capable to form H-bonds between the methoxy groups of the aromatic ring B with Trp130 and Gly247.
Biotransformation of Benzoate to 2,4,6-Trihydroxybenzophenone by Engineered Escherichia coli
Authors: Klamrak Anuwatchakij , Nabnueangsap Jaran , Nualkaew Natsajee
Published: May 2021

The synthesis of natural products by E. coli is a challenging alternative method of environmentally friendly minimization of hazardous waste. Here, we establish a recombinant E. coli capable of transforming sodium benzoate into 2,4,6-trihydroxybenzophenone (2,4,6-TriHB), the intermediate of benzophenones and xanthones derivatives, based on the coexpression of benzoate-CoA ligase from Rhodopseudomonas palustris (BadA) and benzophenone synthase from Garcinia mangostana (GmBPS). It was found that the engineered E. coli accepted benzoate as the leading substrate for the formation of benzoyl CoA by the function of BadA and subsequently condensed, with the endogenous malonyl CoA by the catalytic function of BPS, into 2,4,6-TriHB. This metabolite was excreted into the culture medium and was detected by the high-resolution LC-ESI-QTOF-MS/MS. The structure was elucidated by in silico tools: Sirius 4.5 combined with CSI FingerID web service. The results suggested the potential of the new artificial pathway in E. coli to successfully catalyze the transformation of sodium benzoate into 2,4,6-TriHB. This system will lead to further syntheses of other benzophenone derivatives via the addition of various genes to catalyze for functional groups.
The Potential Role of Polyphenols in Modulating Mitochondrial Bioenergetics within the Skeletal Muscle: A Systematic Review of Preclinical Models
Authors: Mthembu Sinenhlanhla X. H. , Dludla Phiwayinkosi V. , Ziqubu Khanyisani , Nyambuya Tawanda M. , Kappo Abidemi P. , Madoroba Evelyn , Nyawo Thembeka A. , Nkambule Bongani B. , Silvestri Sonia , Muller Christo J. F. , Mazibuko-Mbeje Sithandiwe E.
Published: May 2021

Polyphenols are naturally derived compounds that are increasingly being explored for their various health benefits. In fact, foods that are rich in polyphenols have become an attractive source of nutrition and a potential therapeutic strategy to alleviate the untoward effects of metabolic disorders. The last decade has seen a rapid increase in studies reporting on the bioactive properties of polyphenols against metabolic complications, especially in preclinical models. Various experimental models involving cell cultures exposed to lipid overload and rodents on high fat diet have been used to investigate the ameliorative effects of various polyphenols against metabolic anomalies. Here, we systematically searched and included literature reporting on the impact of polyphenols against metabolic function, particularly through the modulation of mitochondrial bioenergetics within the skeletal muscle. This is of interest since the skeletal muscle is rich in mitochondria and remains one of the main sites of energy homeostasis. Notably, increased substrate availability is consistent with impaired mitochondrial function and enhanced oxidative stress in preclinical models of metabolic disease. This explains the general interest in exploring the antioxidant properties of polyphenols and their ability to improve mitochondrial function. The current review aimed at understanding how these compounds modulate mitochondrial bioenergetics to improve metabolic function in preclinical models on metabolic disease.
Semisynthesis of Selenoauraptene
Authors: Fiorito Serena , Epifano Francesco , Marchetti Lorenzo , Genovese Salvatore
Published: May 2021

Selenium-containing compounds are gaining more and more interest due to their valuable and promising pharmacological properties, mainly as anticancer and antioxidant agents. Ebselen, the up to now only approved drugs, is well known to possess very good glutathione peroxidase mimicking effects. To date, the most of efforts have been directed to build pure synthetic Se containing molecules, while less attention have been devoted to Se-based semisynthetic products resembling natural compounds like terpenes, polyphenols, and alkaloids. The aim of this short communication is to report the synthesis of the first example of a Se-phenylpropanoids, namely selenoauraptene, containing a selenogeranyl side chain in position 7 of the umbelliferone core. The key step was the Newman-Kwart rearrangement to obtain a selenocarbamate in which the Se atom was directly attached to umbelliferone (replacing its 7-OH function) followed by hydrolysis to get diumbelliferyl diselenide, which was finally easily converted to the desired Se-geranyl derivative in quite a good overall yield (28.5%). The synthesized adduct displayed a greater antioxidant and a radical scavenger in vitro activity than parent auraptene. The procedure we describe herein, to the best of our knowledge for the first time in the literature, represents an easy-to-handle method for the synthesis of a wide array of seleno analogues of naturally occurring biologically active oxyprenylated secondary metabolites.
Current Trends in the Application of Nanomaterials for the Removal of Pollutants from Industrial Wastewater Treatment—A Review
Authors: Palani Geetha , Arputhalatha A. , Kannan Karthik , Lakkaboyana Sivarama Krishna , Hanafiah Marlia M. , Kumar Vinay , Marella Ravi Kumar
Published: May 2021

In the recent decades, development of new and innovative technology resulted in a very high amount of effluents. Industrial wastewaters originating from various industries contribute as a major source of water pollution. The pollutants in the wastewater include organic and inorganic pollutants, heavy metals, and non-disintegrating materials. This pollutant poses a severe threat to the environment. Therefore, novel and innovative methods and technologies need to adapt for their removal. Recent years saw nanomaterials as a potential candidate for pollutants removal. Nowadays, a range of cost-effective nanomaterials are available with unique properties. In this context, nano-absorbents are excellent materials. Heavy metal contamination is widespread in underground and surface waters. Recently, various studies focused on the removal of heavy metals. The presented review article here focused on removal of contaminants originated from industrial wastewater utilizing nanomaterials.
pH-Dependent Photoinduced Interconversion of Furocoumaric and Furocoumarinic Acids
Authors: Skarga Vladislav V. , Matrosov Anton A. , Nichugovskiy Artemiy I. , Negrebetsky Vadim V. , Maslov Mikhail A. , Boldyrev Ivan A. , Malakhov Mikhail V.
Published: May 2021

Photo-controlled or photo-regulated molecules, especially biologically active and operating in physiological conditions, are in steady demand. Herein, furocoumaric and furocoumarinic acids being (Z/E)-isomers relative to each other were obtained in two stages starting from psoralen: the alkaline solvolysis of psoralen led to furocoumaric acid, which was further Z → E photoisomerized (365 nm) to furocoumarinic acid. The kinetics of Z → E photoisomerization was monitored by HPLC and UV-vis spectrophotometry. Photophysical characteristics in the aqueous phase for both acids, as well as the reversibility of (Z/E) photoisomerization process, were also assessed. Furocoumarinic acid was found to be visibly fluorescent at pH 2.0–12.0, with the maxima of fluorescence emission spectra being pH-dependent. The reverse E → Z photoisomerization predicted by quantum chemistry calculations as energetically favorable for the monoanionic form of furocoumarinic acid was proved in the experiment while being complicated by pyrone ring closure back to psoralen in acidic and neutral conditions. The preparative synthesis of furocoumarinic acid outlined in this work is particularly valuable in view of a wide range of pharmacological effects previously predicted for this compound.
Translating Analytical Techniques in Geochemistry to Environmental Health
Authors: Doherty Cathleen L. , Buckley Brian T.
Published: May 2021

From human health exposure related to environmental contamination to ancient deep-Earth processes related to differentiation of the Earth’s geochemical reservoirs, the adaptability of inductively coupled plasma mass spectrometry (ICP-MS) has proven to be an indispensable standard technique that transcends disciplines. Continued advancements in ICP-MS, including improved auxiliary applications such as laser ablation (LA), ion/liquid chromatography (IC), automated pre-concentration systems (e.g., seaFAST), and improved desolvating nebulizer systems (e.g., Aridus and Apex) have revolutionized our ability to analyze almost any sample matrix with remarkable precision at exceedingly low elemental abundances. The versatility in ICP-MS applications allows for effective interdisciplinary crossover, opening a world of analytical possibilities. In this communication, we discuss the adaptability of geochemical techniques, including sample preparation and analysis, to environmental and biological systems, using Pb isotopes for source apportionment as a primary example.
Quality Evaluation of Light- and Dark-Colored Hungarian Honeys, Focusing on Botanical Origin, Antioxidant Capacity and Mineral Content
Authors: Bodó Alexandra , Radványi Lilla , Kőszegi Tamás , Csepregi Rita , Nagy Dávid U. , Farkas Ágnes , Kocsis Marianna
Published: May 2021

Melissopalynology, antioxidant capacity and mineral and toxic element contents were analyzed in eight types of Hungarian honeys. Based on color, two groups were distinguished: light honeys comprised acacia, amorpha, phacelia and linden honeys; while dark honeys included sunflower, chestnut, fennel and sage honeys, with 100 to 300 and 700 to 1500 mAU, respectively. The unifloral origin of each sample was supported using pollen analysis. The absorbance of honey correlated positively with antioxidant capacity determined by three different methods (TRC, DPPH, ORAC), and also with mineral content. The exception was the light amber linden honey with significantly higher K content and antiradical activity than other light honeys. The Mn, Zn and Fe contents were the highest in chestnut, sunflower and fennel honeys, respectively. The black meadow sage honey performed best regarding the content of other elements and antioxidant activity. The concentrations of several toxic elements were below the detection limit in the samples, indicating their good quality. The principal component analysis (PCA) revealed correlations between different antioxidant assays and minerals, and furthermore, confirmed the botanical authentication of the honeys based on the studied parameters. To our best knowledge, the present study is the first to provide a complex analysis of quality parameters of eight unifloral Hungarian honeys.
Potential Use of Nitrogen-Doped Carbon Nanotube Sponges as Payload Carriers Against Malignant Glioma
Authors: Salazar Alelí , Pérez-de la Cruz Verónica , Muñoz-Sandoval Emilio , Chavarria Víctor , García Morales María de Lourdes , Espinosa-Bonilla Alejandra , Sotelo Julio , Jiménez-Anguiano Anabel , Pineda Benjamín
Published: May 2021

Glioblastoma is the most aggressive brain tumor with a low median survival of 14 months. The only Food and Drug Administration (FDA)-approved treatment for topical delivery of the cancer drug carmustine is Gliadel. However, its use has been associated with several side-effects, mainly provoked by a mass effect. Nitrogen-doped carbon nanotube sponges (N-CNSs) are a new type of nanomaterial exhibiting high biocompatibility, and they are able to load large amounts of hydrophobic drugs, reducing the amount of carriers. This study evaluated the use of N-CNSs as potential carmustine carriers using malignant glioma cell lines. N-CNSs were characterized by nanoparticle tracking analysis and transmission electron microscopy. The biocompatibility of N-CNSs was determined in glioma cell lines and in primary astrocytes. Afterward, N-CNSs were loaded with carmustine (1:10 w/w), and the drug and liberation efficiency, as well as cytotoxicity induction, were determined. N-CNSs presented a homogeneous size distribution formed by round nanotubes, without induced cytotoxicity, at concentrations below 40 µg/mL. The N-CNSs loaded with carmustine exhibited a continuous kinetic release of carmustine with a maximum release after 72 h. The cytotoxic effect of N-CNSs loaded with carmustine was similar to that of carmustine alone. The results demonstrated that N-CNSs are a biocompatible nanostructure that could be used as carriers for the tumoral load of large amounts of chemotherapeutic agents.
Effects of ZnMgO Electron Transport Layer on the Performance of InP-Based Inverted Quantum Dot Light-Emitting Diodes
Authors: Zhang Binbin , Luo Yu , Mai Chaohuang , Mu Lan , Li Miaozi , Wang Junjie , Xu Wei , Peng Junbiao
Published: May 2021

An environment-friendly inverted indium phosphide red quantum dot light-emitting diode (InP QLED) was fabricated using Mg-doped zinc oxide (ZnMgO) as the electron transport layer (ETL). The effects of ZnMgO ETL on the performance of InP QLED were investigated. X-ray diffraction (XRD) analysis indicated that ZnMgO film has an amorphous structure, which is similar to zinc oxide (ZnO) film. Comparison of morphology between ZnO film and ZnMgO film demonstrated that Mg-doped ZnO film remains a high-quality surface (root mean square roughness: 0.86 nm) as smooth as ZnO film. The optical band gap and ultraviolet photoelectron spectroscopy (UPS) analysis revealed that the conduction band of ZnO shifts to a more matched position with InP quantum dot after Mg-doping, resulting in the decrease in turn-on voltage from 2.51 to 2.32 V. In addition, the ratio of irradiation recombination of QLED increases from 7% to 25% using ZnMgO ETL, which can be attributed to reduction in trap state by introducing Mg ions into ZnO lattices. As a result, ZnMgO is a promising material to enhance the performance of inverted InP QLED. This work suggests that ZnMgO has the potential to improve the performance of QLED, which consists of the ITO/ETL/InP QDs/TCTA/MoO3/Al, and Mg-doping strategy is an efficient route to directionally regulate ZnO conduction bands.
High Prevalence of Stunting and Anaemia Is Associated with Multiple Micronutrient Deficiencies in School Children of Small-Scale Farmers from Chamwino and Kilosa Districts, Tanzania
Authors: Gowele Victoria Flavian , Kinabo Joyce , Jumbe Theresia , Rybak Constance , Stuetz Wolfgang
Published: May 2021

Inadequate macro- and micronutrient nutrition and its consequences, such as anaemia, iron and vitamin deficiency, and growth retardation, could particularly affect children of small-scale farmers. In the present cross-sectional study, 666 school children aged 5–10 years from villages of Chamwino and Kilosa districts were studied for associations between nutritional and micronutrient status and dietary intake. The overall prevalence of stunting, underweight, and overweight was 28.1, 14.4, and 5%, while that of anaemia and deficiency of iron (ID), vitamin A (VAD), and zinc (ZnD) was 42.9, 29.3, 24.9, and 26.4%, respectively. Dietary recalls (24h) revealed that, except of iron (74%), only small proportions of children reached the recommended daily micronutrient intakes: 4% for zinc, 19% for vitamin A, and 14–46% for B vitamins. Stunting was highly associated with wasting in both districts and with VAD in Chamwino. Anaemia was predicted by ID, VAD, and ZnD in Chamwino and by elevated infection markers, C-reactive protein (CRP) and α-1 glycoprotein (AGP), in Kilosa. Overall, elevated CRP and/or AGP increased the risk while higher serum carotenoids indicating a diet of more fruit and vegetables reduced the risk of VAD. The significantly lower prevalence of anaemia and ID in Chamwino was related to higher iron and vitamin A intake and the consumption of mainly bulrush millet with dark green leafy vegetables compared to maize or rice with legumes in Kilosa. Nutrition and hygiene education integrated with home and school garden programmes could reduce the multiple burdens of anaemia; micronutrient deficiencies and infections; and, in the long term, the prevalence of stunting.
Health-Related Quality of Life and Experiences of Brazilian Celiac Individuals over the Course of the Sars-Cov-2 Pandemic
Authors: Falcomer Ana Luísa , Farage Priscila , Pratesi Cláudia B. , Pratesi Riccardo , Gandolfi Lenora , Nakano Eduardo Yoshio , Raposo António , Zandonadi Renata Puppin
Published: May 2021

Since the end of 2019, the world has been facing an unpredicted COVID-19 pandemic with consequences for the economy, environment, society, and health. The COVID-19 pandemic has increased the risk of death, bringing unbearable psychological pressure upon people worldwide. For celiac patients, the pandemic may represent an additional burden concerning the inherent aspects of celiac disease (CD) that compromise these individuals’ quality of life (QoL). Therefore, the objective of this study was to evaluate Brazilian celiac patients’ QoL during the course of the COVID-19 pandemic caused by its outbreak and rapid spread and subsequent restrictive measures in addition to the dietary restrictions and other burdens caused by CD. This country-wide cross-sectional study was conducted using a self-administered instrument previously validated in Brazilian–Portuguese to investigate the QoL of individuals with CD. Data collected through the online self-administration of the Brazilian version of the celiac disease quality of life questionnaire (CDQ) comprised 674 CD individuals’ responses. Although pandemics have historically posed a challenge for Brazilian population, this period was not associated with a negative impact on Brazilian CD individuals’ QoL. During the pandemic, the QoL of Brazilian’s with CD was more affected by gastrointestinal aspects than emotions and social aspects and worries. Gender, age, marital status, having (or not) children, occupation, and a positive test for COVID-19 did not affect CD individuals’ QoL. However, the study revealed a larger burden and diminished QoL for individuals not following a gluten-free diet and those using antidepressants. Additional research is necessary to verify how the length of the pandemic will affect celiac individuals and then compare those outcomes compare to the COVID-19 period and after.
Tocotrienols Ameliorate Neurodegeneration and Motor Deficits in the 6-OHDA-Induced Rat Model of Parkinsonism: Behavioural and Immunohistochemistry Analysis
Authors: Kumari Mangala , Ramdas Premdass , Radhakrishnan Ammu Kutty , Kutty Methil Kannan , Haleagrahara Nagaraja
Published: May 2021

Parkinson’s disease (PD) is a debilitating neurodegenerative disease, which progresses over time, causing pathological depigmentation of the substantia nigra (SN) in the midbrain due to loss of dopaminergic neurons. Emerging studies revealed the promising effects of some nutrient compounds in reducing the risk of PD. One such nutrient compound that possess neuroprotective effects and prevents neurodegeneration is tocotrienol (T3), a vitamin E family member. In the present study, a single dose intracisternal injection of 250 µg 6-hydroxydopamine (6-OHDA) was used to induce parkinsonism in male Sprague Dawley (SD) rats. Forty-eight hours post injection, the SD rats were orally supplemented with alpha (α)- and gamma (γ)-T3 for 28 days. The neuroprotective effects of α- and γ-T3 were evaluated using behavioural studies and immunohistochemistry (IHC). The findings from this study revealed that supplementation of α- and γ-T3 was able to ameliorate the motor deficits induced by 6-OHDA and improve the neuronal functions by reducing inflammation, reversing the neuronal degradation, and preventing further reduction of dopaminergic neurons in the SN and striatum (STR) fibre density.