jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Pratik Kumar | Luke D. Lavis
Source: Annual Review of Neuroscience (review, 2022-02-28)
Field: Materials Science — Materials Chemistry

Melding Synthetic Molecules and Genetically Encoded Proteins to Forge New Tools for Neuroscience Unraveling the complexity of the brain requires sophisticated methods to probe and perturb neurobiological processes with high spatiotemporal control. The field of chemical biology has produced general strategies to combine the molecular specificity of small-molecule tools with the cellular specificity of genetically encoded reagents. Here, we survey the application, refinement, and extension of these hybrid small-molecule:protein methods to problems in neuroscience, which yields powerful reagents to precisely measure and manipulate neural systems. Neuroscience ; Systems neuroscience ; Synthetic biology ; Computational biology ; Computer science ; Biology ; Central nervous system Photochromic and Fluorescence Chemistry ; Photoreceptor and optogenetics research ; Chemical Synthesis and Analysis
Authors: Nils Wilharm | T. Fischer | Alexander Hayn | Stefan G. Mayr
Source: Polymers (article, 2022-10-20)
Field: Materials Science — Biomaterials

Structural Breakdown of Collagen Type I Elastin Blend Polymerization Biopolymer blends are advantageous materials with novel properties that may show performances way beyond their individual constituents. Collagen elastin hybrid gels are a new representative of such materials as they employ elastin's thermo switching behavior in the physiological temperature regime. Although recent studies highlight the potential applications of such systems, little is known about the interaction of collagen and elastin fibers during polymerization. In fact, the final network structure is predetermined in the early and mostly arbitrary association of the fibers. We investigated type I collagen polymerized with bovine neck ligament elastin with up to 33.3 weight percent elastin and showed, by using a plate reader, zeta potential and laser scanning microscopy (LSM) experiments, that elastin fibers bind in a lateral manner to collagen fibers. Our plate reader experiments revealed an elastin concentration-dependent increase in the polymerization rate, although the rate increase was greatest at intermediate elastin concentrations. As elastin does not significantly change the structural metrics pore size, fiber thickness or 2D anisotropy of the final gel, we are confident to conclude that elastin is incorporated homogeneously into the collagen fibers. Elastin ; Tropoelastin ; Polymerization ; Materials science ; Biophysics ; Composite material ; Polymer ; Polymer chemistry ; Chemistry ; Chemical engineering ; Biology Collagen: Extraction and Characterization ; Connective tissue disorders research ; Protease and Inhibitor Mechanisms
Authors: Anjali Pawar | Vaishnavi Kamdi | Ashwini Alaspure | Purushottam Gangane
Source: International Journal of Pharmaceutical Sciences Review and Research (review, 2022-03-15)
Field: Materials Science — Biomaterials

Recent Updates on Polymeric Micelles: A Review Polymeric micelles are a promising method for drug delivery and drug targeting research. Polymeric micelles are nano-sized colloid particles that self-assemble from amphiphilic block co-polymers and they are more stable than surfactant micelles, and their inner core can solubilize large amounts of hydrophobic substances. In this article we have reviewed several aspects related to polymeric micelles like fundamental of polymeric micelles such as general feature, main properties, size, shape, structure analysis and chemistry of polymeric micelles, mechanism of micelles formation. The types of polymeric micelles also highlighted. Here, we have especially emphasized recent advancement of polymeric micelles application like treatment of cancer, treatment of Covid-19 and oral drug delivery, cutaneous drug delivery, polynucleotide delivery and delivery to brain by using polymeric micelles as a nanocarrier. Micelle ; Nanocarriers ; Amphiphile ; Drug delivery ; Polymer ; Materials science ; Pulmonary surfactant ; Chemistry ; Chemical engineering ; Nanotechnology ; Copolymer ; Organic chemistry ; Aqueous solution Nanoparticle-Based Drug Delivery ; Nanomaterials for catalytic reactions ; Dendrimers and Hyperbranched Polymers
Authors: Sreenivas Avula | Xudan Peng | Xingfen Lang | Micky D. Tortorella | Béatrice Josselin | Stéphane Bach | Stéphane Bourg | Pascal Bonnet | Frédéric Buron | Sandrine Ruchaud | Sylvain Routier | Cléopatra Neagoie
Source: Journal of Enzyme Inhibition and Medicinal Chemistry (article, 2022-06-07)
Field: Chemistry — Organic Chemistry

Design and biological evaluation of substituted 5,7-dihydro-6 <i>H</i> -indolo[2,3- <i>c</i> ]quinolin-6-one as novel selective Haspin inhibitors A library of substituted indolo[2,3-<i>c</i>]quinolone-6-ones was developed as simplified Lamellarin isosters. Synthesis was achieved from indole after a four-step pathway sequence involving iodination, a Suzuki-Miyaura cross-coupling reaction, and a reduction/lactamization sequence. The inhibitory activity of the 22 novel derivatives was assessed on Haspin kinase. Two of them possessed an IC<sub>50</sub> of 1 and 2 nM with selectivity towards a panel of 10 other kinases including the parent kinases DYRK1A and CLK1. The most selective compound exerted additionally a very interesting cell effect on the osteosarcoma U-2 OS cell line. DYRK1A ; Kinase ; Chemistry ; IC50 ; Selectivity ; Stereochemistry ; Indole test ; Combinatorial chemistry ; Biochemistry ; In vitro Synthesis and Reactivity of Heterocycles ; Bioactive Compounds and Antitumor Agents ; Synthesis and Characterization of Pyrroles
Authors: Turgut Yilmaz | E. Vescovo | Jerzy T. Sadowski | B. Sinković
Source: Physical review. B./Physical review. B (article, 2022-06-10)
Field: Materials Science — Materials Chemistry

Spectroscopic evidence of highly correlated electrons in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mrow><mml:mi>VSe</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:math> We present detailed high-resolution angle-resolved photoemission experiments on $\mathrm{V}{\mathrm{Se}}_{2}$ grown under various conditions. The surface electronic structure optimally grown samples can host high-temperature spectral kink, quasiparticle peak, and the Fermi gap. Collective observation of these electronic features refers to the strong electronic correlation and is usually attributed to the characteristics of superconductors. Temperature evolution of the quasiparticle peak and the Fermi gap also follow the trend observed in high-${T}_{c}$ superconductors as progressive quenching of the quasiparticle peak at a lower temperature than the complete Fermi gap closing. As a result, the quasiparticle peak can be observed up to 100 $\ifmmode\pm\else\textpm\fi{}$5 K while the Fermi gap persists up to $\ensuremath{\sim}$150 K. These realizations can guide future studies to induce high-temperature superconductivity in transition metal dichalcogenides as well as understand the physics behind high-${T}_{c}$ superconductors. Quasiparticle ; Pseudogap ; Fermi surface ; Superconductivity ; Condensed matter physics ; Photoemission spectroscopy ; Fermi level ; Van Hove singularity ; Tetragonal crystal system ; Physics ; Electronic structure ; Materials science ; Electron ; Spectral line ; Nuclear physics ; Quantum mechanics ; Phase (matter) ; Cuprate 2D Materials and Applications ; Iron-based superconductors research ; Electronic and Structural Properties of Oxides
Authors: Daniil Zhukovsky | Dmitry Dar’in | Olga Bakulina | Mikhail Krasavin
Source: Molecules (review, 2022-03-21)
Field: Chemistry — Organic Chemistry

Preparation and Synthetic Applications of Five-to-Seven-Membered Cyclic α-Diazo Monocarbonyl Compounds The reactivity of cyclic α-diazo monocarbonyl compounds differs from that of their acyclic counterparts. In this review, we summarize the current literature available on the synthesis and synthetic applications of three major classes of cyclic α-diazo monocarbonyl compounds: α-diazo ketones, α-diazo lactones and α-diazo lactams. Diazo ; Reactivity (psychology) ; Chemistry ; Combinatorial chemistry ; Organic chemistry ; Stereochemistry ; Medicine Cyclopropane Reaction Mechanisms ; Catalytic C–H Functionalization Methods ; Synthesis and Catalytic Reactions
Authors: Wendy Wai Yeng Yeo | Sathiya Maran | Amanda Shen-Yee Kong | Wan-Hee Cheng | Swee‐Hua Erin Lim | Jiun‐Yan Loh | Kok‐Song Lai
Source: Materials (review, 2022-08-23)
Field: Materials Science — Materials Chemistry

A Metal-Containing NP Approach to Treat Methicillin-Resistant Staphylococcus aureus (MRSA): Prospects and Challenges Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) is an important cause of pneumonia in humans, and it is associated with high morbidity and mortality rates, especially in immunocompromised patients. Its high rate of multidrug resistance led to an exploration of novel antimicrobials. Metal nanoparticles have shown potent antibacterial activity, thus instigating their application in MRSA. This review summarizes current insights of Metal-Containing NPs in treating MRSA. This review also provides an in-depth appraisal of opportunities and challenges in utilizing metal-NPs to treat MRSA. Staphylococcus aureus ; Methicillin-resistant Staphylococcus aureus ; Pneumonia ; Medicine ; Antimicrobial ; Antibiotics ; Microbiology ; Antibiotic resistance ; Intensive care medicine ; Biology ; Internal medicine ; Bacteria Nanoparticles: synthesis and applications ; Advanced biosensing and bioanalysis techniques ; Advanced Nanomaterials in Catalysis
Authors: Ludivine Poyac | Stefano Scoditti | Xavier Dumail | Michel Granier | Sébastien Clément | Rafael Gramage‐Doria | Charles H. Devillers | Sébastien Richeter
Source: Chemical Communications (article, 2022-01-01)
Field: Chemistry — Organic Chemistry

Electronic, steric and catalytic properties of N-heterocyclic carbene rhodium(<scp>i</scp>) complexes linked to (metallo)porphyrins Electronic and steric properties of NHC ligands functionalized with porphyrins were investigated. When porphyrins are used as NHC-wingtips, nickel(II) in the macrocyle significantly improves the catalytic activity of the neighbouring NHC-Rh(I) complex in the conjugate addition of phenylboronic acid to cyclohexen-2-one. Steric effects ; Carbene ; Rhodium ; Chemistry ; Catalysis ; Conjugate ; Phenylboronic acid ; Electronic effect ; Porphyrin ; Nickel ; Medicinal chemistry ; Polymer chemistry ; Combinatorial chemistry ; Stereochemistry ; Organic chemistry N-Heterocyclic Carbenes in Organic and Inorganic Chemistry ; Catalytic Cross-Coupling Reactions ; Synthetic Organic Chemistry Methods
Authors: Daniel C. Salgueiro | Benjamin Chi | Pablo García‐Reynaga | Daniel J. Weix
Source: ChemRxiv (preprint, 2022-02-21)
Field: Chemistry — Organic Chemistry

Arylation of Pharmaceutically Relevant Strained Rings Using Electronically Tuned Redox-Active Esters Strained rings are increasingly important for the design of pharmaceutical candidates due to their improved pharmacokinetic and safety profiles, as well as their ability to orient substituents into favorable geometries for the potential improvement of the binding affinity to the biological target. Despite their importance, methodologies to cross-couple strained rings have been underdeveloped. The most abundant source of strained carbocycles and heterocycles is the corresponding carboxylic acid, making methods that employ this substrate pool attractive. Coupling of these carboxylic acids with halides, a second source of abundant building blocks, would allow for rapid access to a diverse set of functionalized carbocyclic and heterocyclic frameworks containing all-carbon quaternary centers. Herein we disclose the development of a nickel-catalyzed cross-electrophile approach that couples a variety of strained ring N-hydroxyphthalimide esters, derived from the carboxylic acid in one step or in situ, with various aryl and heteroaryl halides under reductive conditions. The key to this success was the electronic modification of the NHP ester to make them less reactive, as well as the discovery of a new ligand, t-BuBpyCamCN, that avoids problematic side reactions. This method enables the incorporation of 3-membered rings, 4-membered rings, and bicyclic fragments onto (hetero)arenes derived from (hetero)aryl iodides and (hetero)aryl bromides, allowing for straightforward and direct access to arylated strained rings. Electrophile ; Aryl ; Chemistry ; Combinatorial chemistry ; Ring (chemistry) ; Ligand (biochemistry) ; Carboxylic acid ; Halide ; Substrate (aquarium) ; Nickel ; Bicyclic molecule ; Catalysis ; Stereochemistry ; Organic chemistry ; Alkyl ; Receptor Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions ; Radical Photochemical Reactions
Authors: Matteo Vanni | Giacomo Provinciali | Fuencisla Delgado Calvo | Elisa Carignani | Sébastien Dreyfuss | Nicolas Mézailles | Antonio Massimiliano Mio | Giuseppe Nicotra | Stefano Caporali | Silvia Borsacchi | Maurizio Peruzzini | Maria Caporali
Source: ChemCatChem (article, 2022-06-17)
Field: Chemistry — Organic Chemistry

Ru‐P Nanoalloy from Elemental Phosphorus as P‐Source: Synthesis, Characterization and Catalytic Evaluation Abstract Binary ruthenium‐phosphorus nanoparticles (NPs) with different Ru/P ratio were prepared in mild conditions using white phosphorus (P 4 ) as phosphorus source. Accurate study of both their morphology and structure at the atomic level by TEM and HAADF‐STEM, respectively, showed that Ru 2 P and RuP have a narrow size distribution ( ca . 3.3 nm) and are lacking an ordered ruthenium phosphide lattice. 31 P Solid State NMR highlighted the existence of three different phosphorus species consistently with the lack of a metal phosphide lattice and finally XPS revealed that the true nature of these nanoparticles can be better described as a ruthenium‐phosphorus alloy. As a benchmark test, the selective hydrogenation of nitroarenes to primary aromatic amines was studied and evidenced how the P‐alloying imparts a surface modification resulting in a higher catalytic activity and excellent chemoselectivity of Ru 2 P in comparison to Ru(0) and RuP. Phosphide ; Ruthenium ; Chemoselectivity ; Catalysis ; X-ray photoelectron spectroscopy ; Phosphorus ; White Phosphorus ; Nanoparticle ; Inorganic chemistry ; Materials science ; Nuclear chemistry ; Chemistry ; Chemical engineering ; Nanotechnology ; Organic chemistry ; Metallurgy Nanomaterials for catalytic reactions ; Catalysis and Hydrodesulfurization Studies ; Asymmetric Hydrogenation and Catalysis
Authors: Martina Marinelli | Massimiliano Lanzi | Filippo Pierini | Yasamin Ziai | Alberto Zanelli | Debora Quadretti | Francesca Di Maria | Elisabetta Salatelli
Source: Polymers (article, 2022-09-22)
Field: Materials Science — Polymers and Plastics

Ionic Push–Pull Polythiophenes: A Further Step towards Eco-Friendly BHJ Organic Solar Cells Four new conjugated polymers alternating benzothiadiazole units and thiophene moieties functionalized with ionic phosphonium or sulfonic acid salts in the side chains were synthesized by a postfunctionalization approach of polymeric precursors. The introduction of ionic groups makes the conjugated polymers soluble in water and/or polar solvents, allowing for the fabrication of bulk heterojunction (BHJ) solar cells using environmentally friendly conditions. All polymers were fully characterized by spectroscopic, thermal, electrochemical, X-ray diffraction, scanning electron, and atomic force techniques. BHJ solar cells were obtained from halogen-free solvents (i.e., ethanol and/or anisole) by blending the synthesized ionic push-pull polymers with a serinol-fullerene derivative or an ionic homopolymer acting as electron-acceptor (EA) or electron-donor (ED) counterparts, respectively. The device with the highest optical density and the smoothest surface of the active layer was the best-performing, showing a 4.76% photoconversion efficiency. Polymer solar cell ; Polymer ; Ionic bonding ; Ionic liquid ; Materials science ; Thiophene ; Phosphonium ; Polymer chemistry ; Thermal stability ; Chemical engineering ; Conjugated system ; Photoactive layer ; Chemistry ; Organic chemistry ; Ion Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Ionic liquids properties and applications
Authors: Lenka Gajzlerová | Jana Navrátilová | Sona Zenzingerova | David Jaška | Lubomír Beníček | Michal Kudláček | Roman Čermák | Martin Obadal
Source: eXPRESS Polymer Letters (article, 2022-01-01)
Field: Materials Science — Polymers and Plastics

On isotactic polypropylene annealing: Difference in final properties of neat and β-nucleated polypropylene The effect of isotactic polypropylene (iPP) molecular weight and thermal treatment on final crystalline structure and mechanical properties were investigated by X-ray scattering, differential scanning calorimetry, tensile testing, and scanning electron microscopy. Neat and -nucleated isotactic polypropylene were subjected to annealing above melting temperature of -phase but still below melting temperature of -phase, which caused both improvement of crystallites and to -recrystallization, in case of nucleated material. As a consequence, the final mechanical properties like tensile strength and stiffness improved significantly. The increase is much more pronounced in the case of to -transformed materials with lower molecular weight. This phenomenon can also be attributed to the partial preservation of the specific structure of the amorphous phase present in -nucleated polypropylene, in addition to the perfection of the crystalline phase. The amorphous phase comprises many interconnecting chains passing through several lamellae whereby providing a long-range effect. Tacticity ; Materials science ; Polypropylene ; Differential scanning calorimetry ; Annealing (glass) ; Amorphous solid ; Composite material ; Ultimate tensile strength ; Crystallite ; Recrystallization (geology) ; Polymer ; Crystallography ; Thermodynamics ; Polymerization Polymer crystallization and properties ; Polymer Nanocomposites and Properties
Authors: Philip Norcott
Source: Physical Chemistry Chemical Physics (article, 2022-01-01)
Field: Chemistry — Spectroscopy

Selective NMR detection of individual reaction components hyperpolarised by reversible exchange with para-hydrogen NMR spectroscopy can sometimes be hampered by two inherent weaknesses: low sensitivity and overlap of signals in complex mixtures. Hyperpolarisation techniques using para-hydrogen (including the method known as SABRE) can overcome this sensitivity problem, but cannot circumvent spectral overlap. Conversely, a recently described selective excitation technique (known as DREAMTIME) can overcome overlap in mixtures, but suffers from a decrease in sensitivity. Here we demonstrate the combination of these two methods in a single approach termed SABRE-DREAM, to selectively provide hyperpolarised signals of user-specified components of a chemical reaction, where otherwise overlapping <sup>1</sup>H signals would hinder reaction monitoring or analysis. Sensitivity (control systems) ; Chemistry ; Hydrogen ; Biological system ; Nuclear magnetic resonance spectroscopy ; Excitation ; Chemical physics ; Physics ; Stereochemistry ; Organic chemistry ; Electronic engineering Advanced NMR Techniques and Applications ; Solid-state spectroscopy and crystallography ; Atomic and Subatomic Physics Research
Authors: Zainab Sadiq | Mustafa Hassan | Khaleel I. Hassoon
Source: Engineering and Technology Journal (article, 2022-04-25)
Field: Materials Science — Materials Chemistry

Rod-like Nano-structures of Copper Oxide Prepared by Chemical Bath Deposition In this paper, we reported that the annealing at temperatures of 400 and 500 oC in the air for 2 hours led to the formation of rod-like structures of cupric oxide thin films prepared by the chemical bath deposition technique. The structure and the optical properties of the prepared thin films were studied to investigate the role of annealing on the films. The morphology of the as-deposited CuO films is almost structureless. However, the films are converted to rod-like shapes nano-structures after annealing, as confirmed by scanning electron microscopy. The x-ray analysis showed that the thin films of copper oxide nano-structures have a monoclinic crystallinity preferred in the (110), (002), and (111) directions, and the crystallinity increases after annealing. Furthermore, the bandgap values after annealing are reduced from 2.1 to 1.61 and 1.63 eV as determined by optical analysis utilizing UV–VIS spectroscopy. Crystallinity ; Annealing (glass) ; Chemical bath deposition ; Scanning electron microscope ; Materials science ; Thin film ; Monoclinic crystal system ; Oxide ; Copper ; Nano- ; Copper oxide ; Chemical engineering ; Band gap ; Nanotechnology ; Crystallography ; Chemistry ; Composite material ; Metallurgy ; Crystal structure ; Optoelectronics Copper-based nanomaterials and applications ; ZnO doping and properties ; Chalcogenide Semiconductor Thin Films
Authors: Shaochuan Li | Caiping Liu | Qihui Chen | Feilong Jiang | Daqiang Yuan | Qing‐Fu Sun | Maochun Hong
Source: Chemical Science (article, 2022-01-01)
Field: Chemistry — Organic Chemistry

Adaptive coordination assemblies based on a flexible tetraazacyclododecane ligand for promoting carbon dioxide fixation Coordination hosts based on flexible ligands have received increasing attention due to their inherent adaptive cavities that often show induced-fit guest binding and catalysis like enzymes. Herein, we report the controlled self-assembly of a series of homo/heterometallic coordination hosts (Me<sub>4</sub>enPd)<sub>2<i>n</i></sub> (ML) <sub><i>n</i></sub> [<i>n</i> = 2/3; M = Zn(ii)/Co(ii)/Ni(ii)/Cu(ii)/Pd(ii)/Ag(i); Me<sub>4</sub>en: <i>N</i>,<i>N</i>,<i>N</i>',<i>N</i>'-tetramethylethylenediamine] with different shapes (tube/cage) from a flexible tetraazacyclododecane-based pyridinyl ligand (L) and <i>cis</i>-blocking Me<sub>4</sub>enPd(ii) units. While the Ag(i)-metalated ligand (AgL) gave rise to the formation of a (Me<sub>4</sub>enPd)<sub>4</sub>(ML)<sub>2</sub>-type cage, all other M(ii) ions led to isostructural (Me<sub>4</sub>enPd)<sub>6</sub>(ML)<sub>3</sub>-type tubular complexes. Structural transformations between cages and tubes could be realized through transmetalation of the ligand. The buffering effect on the ML panels endows the coordination tubes with remarkable acid-base resistance, which makes the (Me<sub>4</sub>enPd)<sub>6</sub>(ZnL)<sub>3</sub> host an effective catalyst for the CO<sub>2</sub> to CO<sub>3</sub> <sup>2-</sup> conversion. Control experiments suggested that the integration of multiple active Zn(ii) sites on the tubular host and the perfect geometry match between CO<sub>3</sub> <sup>2-</sup> and the cavity synergistically promoted such a conversion. Our results provide an important strategy for the design of adaptive coordination hosts to achieve efficient carbon fixation. Carbon fixation ; Carbon dioxide ; Ligand (biochemistry) ; Fixation (population genetics) ; Chemistry ; Nanotechnology ; Materials science ; Biochemistry ; Gene ; Organic chemistry ; Receptor Supramolecular Chemistry and Complexes ; Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications