jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Asmaa Aboelnaga | Asmaa M. Fahim | Taghreed H. El-Sayed
Source: OnLine Journal of Biological Sciences (article, 2020-04-01)
Field: Chemistry — Organic Chemistry

Computer Aid Screening for Potential Antimalarial Choroquinone Compounds as Covid 19 Utilizing Computational Calculations and Molecular Docking Study Click reaction of 4,7-dichloroquinoline (1) with thiosemicarbazide (2) to afford the corresponding 2-(7-chloroquinolin-4-yl)thiosemicarbazide (3) utilized ultrasonic irradiation which can cyclized easily with ethylacetoacetate to give the 3-(7-chloroquinolin-4ylamino)-tetrahydro-6-methyl-2-thioxopyrimidin-4(1H)-one (4) via nucleophilic substitution reaction. The synthesized compounds was examined in vitro antimalarial activity with IC50 = 11.92, 25.37 g/mL against chloroquinone drug. Furthermore, the theoretical investigation of most active compounds CQT and CQP utilizing of DFT/B3LYP/6-311G(d) and HF/6-311G(d) basis's set and evaluated their physical characters, bond length, bond angles, dihedral angles, also its HOMO-LUMO energy gap was 3.77 eV which indicate the reactivity of CQP. Moreover, the molecular docking studies of these synthesized compounds showed small energy affinity against SARS-CoV-2 main protease (PDBID: 6lu7) and crystal structure of thermoplasma acidophilum (PDBID: 1q2w) and shorter bond length. All these parameters could be considered with different extent to significantly affect the binding affinity of these compounds to the active protein sites for further biological evaluation on Covid-19. Thermoplasma acidophilum ; Docking (animal) ; Dihedral angle ; Chemistry ; Reactivity (psychology) ; Bond length ; HOMO/LUMO ; Combinatorial chemistry ; Click chemistry ; Nucleophile ; Crystallography ; Stereochemistry ; Computational chemistry ; Crystal structure ; Molecule ; Organic chemistry ; Catalysis ; Enzyme ; Hydrogen bond Synthesis and biological activity ; Computational Drug Discovery Methods ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Elsherif Mervat A.
Source: Journal of Applied Pharmaceutical Science (article, 2020-06-05)
Field: Chemistry — Organic Chemistry

Antibacterial evaluation and molecular properties of pyrazolo[3,4-b] pyridines and thieno[2,3-b]pyridines A series of pyrazolo [3,4-b]pyridines (6a-h) and thieno [2,3-b]pyridines (8a-h) was synthesized for the evaluation of their in vitro antibacterial activities against four bacteria species (namely Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) and compared the result with the standard drug (Tetracycline). The result of the antibacterial evaluation showed that some pyrazolo [3,4-b]pyridines and thieno[2,3-b]pyridines display moderate antibacterial activity against the four bacteria species in this study. Furthermore, the physicochemical, pharmacokinetic, and drug-likeness properties were carried out using SwissADME website. The results of molecular properties show that all the pyrazolopyridines 6a-h and thienopyridines 8a-h showed agreement with the Lipinski and Veber rules. The two pyrazolo [3,4-b]pyridines 6b and 6c are almost in the range of the bioavailability radar pink area. Also, pyrazolo [3,4-b]pyridine derivatives 6a-h show high gastrointestinal absorption, all the derivatives except 6c are nonsubstrates for P-glycoprotein, and most of the derivatives show CYP isoform inhibition. This study could be valuable in the discovery of a new series of drugs. Chemistry ; Stereochemistry Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds ; Multicomponent Synthesis of Heterocycles
Authors: Marlene A. Velazco‐Medel | Luis A. Camacho‐Cruz | Emilio Bucio
Source: Medical Devices & Sensors (article, 2020-03-12)
Field: Materials Science — Biomaterials

Modification of relevant polymeric materials for medical applications and devices Abstract The present review compiles different biomedical relevant polymers that have been modified to enhance their properties, giving hydrophilicity to their surfaces, antifouling properties to avoid bacterial adhesion, biocompatibility, incorporation of drug delivery systems and the improving of their mechanical properties to use them in the manufacturing of medical devices as prosthesis or implants, or other medical applications as wound dressers or scaffolds to cell culture. Other content of this work is a general description of the different techniques to modify and graft molecules, biomolecules and other polymers onto polymeric matrices in order to obtain high‐performance biomaterials and medical devices. Biocompatibility ; Biofouling ; Drug delivery ; Materials science ; Nanotechnology ; Biomolecule ; Polymer ; Medical device ; Surface modification ; Biomedical engineering ; Chemistry ; Composite material ; Chemical engineering ; Engineering ; Membrane biodegradable polymer synthesis and properties ; Hydrogels: synthesis, properties, applications ; Electrospun Nanofibers in Biomedical Applications
Authors: Norfatirah Muhamad Sarih | David Romero-Perez | Behnam Bastani | Monrawat Rauytanapanit | C. Boisdon | Thanit Praneenararat | Hairul Anuar Tajuddin | Zanariah Abdullah | Abraham K. Badu‐Tawiah | Simon Maher
Source: Scientific Reports (article, 2020-12-09)
Field: Chemistry — Spectroscopy

Accelerated nucleophilic substitution reactions of dansyl chloride with aniline under ambient conditions via dual-tip reactive paper spray Paper spray ionization (PSI) mass spectrometry (MS) is an emerging tool for ambient reaction monitoring via microdroplet reaction acceleration. PSI-MS was used to accelerate and monitor the time course of the reaction of dansyl chloride with aniline, in acetonitrile, to produce dansyl aniline. Three distinct PSI arrangements were explored in this study representing alternative approaches for sample loading and interaction; conventional single tip as well as two novel setups, a dual-tip and a co-axial arrangement were designed so as to limit any on-paper interaction between reagents. The effect on product abundance was investigated using these different paper configurations as it relates to the time course and distance of microdroplet travel. It was observed that product yield increases at a given distance and then decreases thereafter for all PSI configurations. The fluorescent property of the product (dansyl aniline) was used to visually inspect the reaction progress on the paper substrate during the spraying process. Amongst the variety of sample loading methods the novel dual-tip arrangement showed an increased product yield and microdroplet density, whilst avoiding any on-paper interaction between the reagents. Aniline ; Nucleophilic substitution ; Chemistry ; Chloride ; Nucleophile ; Dual (grammatical number) ; Combinatorial chemistry ; Organic chemistry ; Catalysis Mass Spectrometry Techniques and Applications ; Innovative Microfluidic and Catalytic Techniques Innovation ; Protein purification and stability
Authors: Ryosuke Asato | Colin J. Martin | Jan Patrick Calupitan | Ryo Mizutsu | Takuya Nakashima | Go Okada | Noriaki Kawaguchi | Takayuki Yanagida | Tsuyoshi Kawai
Source: Chemical Science (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Photosynergetic amplification of radiation input: from efficient UV induced cycloreversion to sensitive X-ray detection Five photochromic terarylenes which show reversible photocyclisation and cycloreversion with relatively high quantum yields are presented. Some of these have been observed to undergo a highly efficient cycloreversion cascade process from their coloured, closed forms to their uncoloured open forms that leads to cycloreversion quantum yields significantly larger than unity. This cascade effect can been induced with both chemical and X-ray initiation; the limit of detection from X-ray initiation has been tested and is comparable to existing systems with detection observed at values as low as 0.3 mGy. Photochromism ; Photosensitivity ; Quantum yield ; X-ray ; Sensitivity (control systems) ; Radiation ; Yield (engineering) ; Quantum ; Irradiation ; Optoelectronics ; Materials science ; Chemistry ; Photochemistry ; Optics ; Physics ; Fluorescence ; Engineering ; Quantum mechanics Photochromic and Fluorescence Chemistry ; Luminescence and Fluorescent Materials ; Photoreceptor and optogenetics research
Authors: Tung-Huan Su | Nian-Hu Lu | Chih‐Hsuan Chen | Chuin‐Shan Chen
Source: Materials Today Communications (article, 2020-06-15)
Field: Materials Science — Materials Chemistry

Full-field stress and strain measurements revealing energy dissipation characteristics in martensitic band of Cu-Al-Mn shape memory alloy Materials science ; Pseudoelasticity ; Shape-memory alloy ; Dissipation ; Martensite ; Diffusionless transformation ; Austenite ; Alloy ; Phase (matter) ; Stress (linguistics) ; Metallurgy ; Thermodynamics ; Microstructure Shape Memory Alloy Transformations
Authors: Takayuki Komatsu | Tsuyoshi Honma
Source: Journal of Solid State Chemistry (article, 2020-04-19)
Field: Materials Science — Ceramics and Composites

Crystallization data-driven proposal on distribution model of composition fluctuations in structure of oxide glasses Crystallization ; Metastability ; Materials science ; Oxide ; Viscosity ; Nanoscopic scale ; Mineralogy ; Chemical physics ; Chemical engineering ; Thermodynamics ; Nanotechnology ; Chemistry ; Composite material ; Metallurgy ; Physics Glass properties and applications ; Phase-change materials and chalcogenides ; Pigment Synthesis and Properties
Authors: Samuel M. Blau | Evan Walter Clark Spotte‐Smith | Brandon M. Wood | Shyam Dwaraknath | Kristin A. Persson
Source: ChemRxiv (preprint, 2020-10-12)
Field: Materials Science — Materials Chemistry

Accurate, Automated Density Functional Theory for Complex Molecules Using On-the-fly Error Correction High-throughput density functional theory (DFT) has been widely utilized to study a variety of materials and molecular properties. However, its application to complex molecular systems, including those relevant to electrochemical reactivity and decomposition, has been limited by insufficient automation.Here, we report a broadly applicable, automated framework for the accurate and robust DFT calculation of molecules, capable of addressing species relevant to electrochemistry. This framework is specifically designed to study molecules with different charge states, open-shell electronic structure, metal coordination, and implicit solvation. We first identify appropriate levels of theory that avoid calculation failures and accurately predict molecular redox potentials. We then describe our framework, including methods to automatically detect and correct errors and to optimize structures from saddle points to potential energy surface minima. To demonstrate the efficacy of this framework, we examine a case study including over 12,000 calculations of reactive molecular fragments. This framework is able to reduce the rate of failure for DFT calculations from 25.1% to 1.2%, significantly improving the degree of automation possible for high-throughput molecular DFT. Density functional theory ; Computer science ; Implicit solvation ; Solvation ; Maxima and minima ; Molecule ; Computational chemistry ; Chemistry ; Mathematics Machine Learning in Materials Science ; Electrocatalysts for Energy Conversion ; CO2 Reduction Techniques and Catalysts
Authors: Fabian Delorme | Cong Chen | Frédéric Schœnstein | Nazir Jaber | Florian Jean | Micka Bah | Quentin Simon | T. Chartier | P. Laffez | Isabelle Monot‐Laffez | Fabien Giovannelli
Source: Thermochimica Acta (article, 2020-10-23)
Field: Materials Science — Materials Chemistry

Low intrinsic thermal conductivity of Spark Plasma Sintered dense KNbO3 and NaNbO3 perovskite ceramics Spark plasma sintering ; Ceramic ; Thermal conductivity ; Materials science ; Perovskite (structure) ; Niobium ; Atmospheric temperature range ; Mineralogy ; Analytical Chemistry (journal) ; Conductivity ; Sintering ; Oxide ; Composite material ; Metallurgy ; Thermodynamics ; Crystallography ; Chemistry ; Physical chemistry ; Physics Ferroelectric and Piezoelectric Materials ; Thermal Expansion and Ionic Conductivity ; Microwave Dielectric Ceramics Synthesis
Authors: Lingyan Ping | Sean R. Kundinger | Duc M. Duong | Luming Yin | Marla Gearing | James J. Lah | Allan I. Levey | Nicholas T. Seyfried
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2020-05-21)
Field: Chemistry — Spectroscopy

Global quantitative analysis of the human brain proteome and phosphoproteome in Alzheimer’s disease Abstract Alzheimer’s disease (AD) is characterized by an early, asymptomatic phase (AsymAD) in which individuals exhibit amyloid-beta (Aβ) plaque accumulation in the absence of clinically detectable cognitive decline. Here we report an unbiased multiplex quantitative proteomic and phosphoproteomic analysis using tandem mass tag (TMT) isobaric labeling of human post-mortem cortex ( n =27) across pathology-free controls, AsymAD and symptomatic AD individuals. With off-line high-pH fractionation and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) on an Orbitrap Lumos mass spectrometer, we identified 11,378 protein groups across three TMT 11-plex batches. Immobilized metal affinity chromatography (IMAC) was used to enrich for phosphopeptides from the same TMT-labeled cases and 51,736 phosphopeptides were identified. Of these, 48,992 were quantified by TMT reporter ions representing 33,652 unique phosphosites. Two reference standards in each TMT 11-plex were included to assess intra- and inter-batch variance at the protein and peptide level. This comprehensive human brain proteome and phosphoproteome dataset will serve as a valuable resource for the identification of biochemical, cellular and signaling pathways altered during AD progression. Tandem mass tag ; Isobaric labeling ; Tandem mass spectrometry ; Proteome ; Orbitrap ; Chemistry ; Proteomics ; Quantitative proteomics ; Phosphoprotein ; Mass spectrometry ; Multiplex ; Alzheimer's disease ; Computational biology ; Chromatography ; Biochemistry ; Phosphorylation ; Biology ; Bioinformatics ; Disease ; Protein mass spectrometry ; Medicine ; Pathology Advanced Proteomics Techniques and Applications ; Metabolomics and Mass Spectrometry Studies ; Mass Spectrometry Techniques and Applications
Authors: A. Selmi | M. Mascot | F. Jomni | Jean-Claude Carru
Source: Journal of Alloys and Compounds (article, 2020-01-31)
Field: Materials Science — Materials Chemistry

Investigation of interfacial dead layers parameters in Au/Ba0.85Sr0.15TiO3/Pt capacitor devices Capacitor ; Materials science ; Permittivity ; Dielectric ; Silicon ; Ferroelectricity ; Thin film ; Composite material ; Optoelectronics ; Nanotechnology ; Electrical engineering ; Voltage Ferroelectric and Piezoelectric Materials ; Acoustic Wave Resonator Technologies ; Multiferroics and related materials
Authors: Jialong Wu | Yongwei Wu | Zepeng He | Zihua Li | Huahua Huang | Yongming Chen | Guodong Liang
Source: Science China Materials (article, 2020-08-11)
Field: Materials Science — Materials Chemistry

Conjugated microporous polymers for near-infrared photothermal control of shape change Materials science ; Photothermal therapy ; Polymer ; Monomer ; Photothermal effect ; Microporous material ; Polymerization ; Conjugated microporous polymer ; Conjugated system ; Chemical engineering ; Thermal stability ; Nanotechnology ; Composite material Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Polydiacetylene-based materials and applications
Authors: Pascal Weingart | Yu Sun | Werner R. Thiel
Source: ChemCatChem (article, 2020-10-07)
Field: Chemistry — Inorganic Chemistry

Electronic Fine‐tuning of Ruthenium(II) Transfer Hydrogenation Catalysts with Ethanol as the Hydrogen Source Abstract A series of ruthenium(II) complexes bearing tridentate N,N’‐diallyl‐2,6‐di(5‐butylpyrazol‐3‐yl)pyridine ligands was synthesized and characterized. Introduction of substituents in the 4‐position of the pyrazole rings tune the electron density at the ruthenium center, which was proved by correlation of the 31 P NMR chemical shifts with the σ p parameters of the Hammett equation. The structural elucidation of a phosphine‐free ruthenium(II) complex proves that one of the allyl side‐chains undergoes chelating coordination to the ruthenium site to realize a 18 VE center. This compound is the starting point for complexes of the type (N,N,N)Ru(L)(Cl) 2 bearing ligands L other than triphenylphosphine. The ruthenium(II) complexes were investigated for their activity in the transfer hydrogenation with ethanol as the hydrogen source. Here the logarithms of the measured turn‐over frequencies (TOF) correlate with the σ p parameters of the Hammett equation in terms of a linear free‐energy relationship. Ruthenium ; Chemistry ; Transfer hydrogenation ; Triphenylphosphine ; Catalysis ; Phosphine ; Pyridine ; Osmium ; Chelation ; Photochemistry ; Medicinal chemistry ; Inorganic chemistry ; Organic chemistry Asymmetric Hydrogenation and Catalysis ; Carbon dioxide utilization in catalysis ; Catalysis for Biomass Conversion
Authors: Lukáš Ondič | M. Varga | Jan Fait | Karel Hruška | V. Jurka | Alexander Kromka | Jan Maňák | Peter Kapusta | Jaroslava Nováková
Source: Nanoscale (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Photonic crystal cavity-enhanced emission from silicon vacancy centers in polycrystalline diamond achieved without postfabrication fine-tuning Diamond optical centers have recently emerged as promising single-photon sources for quantum photonics. Particularly, negatively charged silicon vacancy (SiV-) centers show great promise due to their narrow zero-phonon emission line present also at room temperature. However, due to fabrication tolerances it is challenging to prepare directly photonic structures with optical modes spectrally matching the emission of SiV- centers. To reach the spectral overlap, photonic structures must typically undergo complicated post-processing treatment. In this work, suspended photonic crystal cavities made of polycrystalline diamond are engineered and more than 2.5-fold enhancement of the SiV- center zero-phonon line intensity via coupling to the cavity photonic mode is demonstrated. The intrinsic non-homogeneous thickness of the diamond thin layer within the sample is taken as an advantage that enables reaching the spectral overlap between the emission from SiV- centers and the cavity modes without any post-processing. Even with lower optical quality compared to monocrystalline diamond, the fabricated photonic structures show comparable efficiency for intensity enhancement. Therefore, the results of this work may open up a promising route for the application of polycrystalline diamond in photonics. Materials science ; Diamond ; Optoelectronics ; Vacancy defect ; Photonic crystal ; Polycrystalline diamond ; Silicon ; Crystallite ; Crystallography ; Chemistry ; Composite material ; Metallurgy Diamond and Carbon-based Materials Research ; Photonic Crystals and Applications ; Advanced Fiber Laser Technologies
Authors: Agata Krywko‐Cendrowska | Dawid Szweda | Róża Szweda
Source: Processes (article, 2020-05-03)
Field: Materials Science — Materials Chemistry

Well-Defined Conjugated Macromolecules Based on Oligo(Arylene Ethynylene)s in Sensing Macromolecules with well-defined structures in terms of molar mass and monomer sequence became interesting building blocks for modern materials. The precision of the macromolecular structure makes fine-tuning of the properties of resulting materials possible. Conjugated macromolecules exhibit excellent optoelectronic properties that make them exceptional candidates for sensor construction. The importance of chain length and monomer sequence is particularly important in conjugated systems. The oligomer length, monomer sequence, and structural modification often influence the energy bang gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the molecules that reflect in their properties. Moreover, the supramolecular aggregation that is often observed in oligo-conjugated systems is usually strongly affected by even minor structural changes that are used for sensor designs. This review discusses the examples of well-defined conjugated macromolecules based on oligo(arylene ethynylene) skeleton used for sensor applications. Here, exclusively examples of uniform macromolecules are summarized. The sensing mechanisms and importance of uniformity of structure are deliberated. Macromolecule ; Arylene ; Monomer ; Oligomer ; Conjugated system ; Sequence (biology) ; HOMO/LUMO ; Materials science ; Supramolecular chemistry ; Polymer ; Molecule ; Chemistry ; Chemical physics ; Polymer chemistry ; Organic chemistry Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection ; Conducting polymers and applications
Authors: Alexandra Aulova | Marko Bek | L. Yu. Kossovich | Igor Emri
Source: Strojniški vestnik – Journal of Mechanical Engineering (article, 2020-07-15)
Field: Materials Science — Biomaterials

Needleless Electrospinning of PA6 Fibers: The Effect of Solution Concentration and Electrospinning Voltage on Fiber Diameter Needleless electrospinning is the process of forming thin material fibers from the open surface of its solution or melt in a strong electrostatic field. Electrospun non-woven materials are used in various applications that require specific fiber diameters and pore size distributions. Fiber diameter depends on the properties of the polymer solution and manufacturing conditions. A needleless electrospinning process using the Nanospider setup was investigated using the commonly used polyamide 6 (PA6) solution in a mixture of acetic and formic acids. Polymer solutions with different polymer concentrations were characterized by viscosity, surface tension and electrical conductivity. An increase in polymer content in the solution resulted in the exponential increase of the solution viscosity, polynomial increase of electrical conductivity and had almost no effect on surface tension. The effect of the polymer concentration in the solution, as well as electrospinning voltage on fiber diameter and diameter distribution, was investigated using scanning electron microscopy images. The average fiber diameter linearly increases with the increased polymer concentration and also demonstrates an increase with increased electrospinning voltage, although less pronounced. Therefore, a change in the PA6 solution concentration should be used for the robust adjustment of fiber diameter, while changes in electrospinning voltage are more appropriate for fine tuning the fiber diameter during the process of needleless electrospinning. Electrospinning ; Materials science ; Fiber ; Polymer ; Composite material ; Surface tension ; Viscosity ; Nanofiber ; Scanning electron microscope ; Chemical engineering Electrospun Nanofibers in Biomedical Applications