jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Boyce S. Chang | Whitney S. Loo | Beihang Yu | Scott Dhuey | Lei Wan | Paul F. Nealey | Ricardo Ruiz
Source: ACS Applied Materials & Interfaces (article, 2022-12-19)
Field: Materials Science — Materials Chemistry

Sequential Brush Grafting for Chemically and Dimensionally Tolerant Directed Self-Assembly of Block Copolymers We report a method for the directed self-assembly (DSA) of block copolymers (BCPs) in which a first BCP film deploys homopolymer brushes, or "inks", that sequentially graft onto the substrate's surface <i>via</i> the interpenetration of polymer molecules during the thermal annealing of the polymer film on top of existing polymer brushes. By selecting polymer "inks" with the desired chemistry and appropriate relative molecular weights, it is possible to use brush interpenetration as a powerful technique to generate self-registered chemical contrast patterns at the same frequency as that of the domains of the BCP. The result is a process with a higher tolerance to dimensional and chemical imperfections in the guiding patterns, which we showcase by implementing DSA using homopolymer brushes for the guiding features as opposed to more robust cross-linkable mats. We find that the use of "inks" does not compromise the line width roughness, and the quality of the DSA as a lithographic mask is verified by implementing a robust "dry lift-off" pattern transfer. Brush ; Copolymer ; Materials science ; Polymer ; Polymer brush ; Lithography ; Template ; Surface finish ; Nanotechnology ; Chemical engineering ; Polymer chemistry ; Polymerization ; Composite material ; Optoelectronics Block Copolymer Self-Assembly ; Polymer Surface Interaction Studies ; Advanced Polymer Synthesis and Characterization
Authors: Carlos Peña-Varas | Christa Kanstrup | Ariela Vergara‐Jaque | Mariela González‐Avendaño | Christoph Crocoll | Osman Mirza | Ingo Drèyer | Hussam Hassan Nour‐Eldin | David Ramírez
Source: International Journal of Molecular Sciences (article, 2022-01-29)
Field: Materials Science — Materials Chemistry

Structural Insights into the Substrate Transport Mechanisms in GTR Transporters through Ensemble Docking Glucosinolate transporters (GTRs) are part of the nitrate/peptide transporter (NPF) family, members of which also transport specialized secondary metabolites as substrates. Glucosinolates are defense compounds derived from amino acids. We selected 4-methylthiobutyl (4MTB) and indol-3-ylmethyl (I3M) glucosinolates to study how GTR1 from <i>Arabidopsis thaliana</i> transports these substrates in computational simulation approaches. The designed pipeline reported here includes massive docking of 4MTB and I3M in an ensemble of GTR1 conformations (in both inward and outward conformations) extracted from molecular dynamics simulations, followed by clustered and substrate-protein interactions profiling. The identified key residues were mutated, and their role in substrate transport was tested. We were able to identify key residues that integrate a major binding site of these substrates, which is critical for transport activity. In silico approaches employed here represent a breakthrough in the plant transportomics field, as the identification of key residues usually takes a long time if performed from a purely wet-lab experimental perspective. The inclusion of structural bioinformatics in the analyses of plant transporters significantly speeds up the knowledge-gaining process and optimizes valuable time and resources. Docking (animal) ; Transporter ; Computational biology ; Chemistry ; Biophysics ; Biology ; Biochemistry ; Medicine ; Gene Enzyme Structure and Function ; Pancreatic function and diabetes ; Genetics and Neurodevelopmental Disorders
Authors: Zachary J. Woessner | George R. Lewis | Sandra L. A. Bueno | Emilie Ringe | Sara E. Skrabalak
Source: Nanoscale (article, 2022-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Asymmetric seed passivation for regioselective overgrowth and formation of plasmonic nanobowls Plasmonic nanoparticles (NPs) have garnered excitement over the past several decades stemming from their unique optoelectronic properties, leading to their use in various sensing applications and theranostics. Symmetry dictates the properties of many nanomaterials, and nanostructures with low, but still defined symmetries, often display markedly different properties compared to their higher symmetry counterparts. While numerous methods are available to manipulate symmetry, surface protecting groups such as polymers are finding use due to their ability to achieve regioselective modification of NP seeds, which can be removed after overgrowth as shown here. Specifically, poly(styrene-<i>b</i>-polyacrylic acid) (PSPAA) is used to asymmetrically passivate cubic Au seeds through competition with hexadecyltrimethylammonium bromide (CTAB) ligands. The asymmetric passivation <i>via</i> collapsed PSPAA causes only select vertices and faces of the Au cubes to be available for deposition of new material (<i>i.e.</i>, Au, Au-Ag alloy, and Au-Pd alloy) during seeded overgrowth. At low metal precursor concentrations, deposition follows observations from unpassivated seeds but with new material growing from only the exposed seed portions. At high metal precursor concentrations, nanobowl-like structures form from interaction between the depositing phase and the passivating PSPAA. Through experiment and simulation, the optoelectronic properties of these nanobowls were probed, finding that the interiors and exteriors of the nanobowls can be functionalized selectively as revealed by surface enhanced Raman spectroscopy (SERS). Passivation ; Regioselectivity ; Plasmon ; Materials science ; Nanotechnology ; Optoelectronics ; Chemistry ; Layer (electronics) ; Organic chemistry ; Catalysis Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Photonic Crystals and Applications
Authors: Mohamed Salaheldeen | Asma Wederni | M. Ipatov | V. Zhukova | Julian Maria González | А. Zhukov
Source: Preprints.org (preprint, 2022-12-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Elucidation of the Strong Effect of the Annealing and the Magnetic Field on the Magnetic Properties of Ni&lt;sub&gt;2&lt;/sub&gt;-based Heusler Microwires We studied the effect of annealing and the applied magnetic field from 50 Oe to 20 kOe on the magneto-structural behavior of Ni2FeSi-based Heusler microwires fabricated by using Taylor-Ulitovsky technique. Using the XRD analysis, a strong effect of annealing, manifested as the development of the crystallization process, was observed. The average grain size and crystalline phase content of annealed sample increase from 21.3 nm and 34 % to 32.8 nm and 79%, respectively, as-compared to the as-prepared one. In addition, upon annealing phase transforms into a monoclinic martensitic structure with modulation 10M were observed, which cannot be found in the as-prepared sample. Concerning the magnetic properties, both samples show ferromagnetic behavior below and above the room temperature, where the Curie temperature of Ni2FeSi is higher than room temperature. The induced secondary phases have a noticeable effect on the magnetic behavior of the annealed sample, where a high normalized saturation magnetization (NMs) and low normalized reduced remenance (Mr = M/M5K), compared to the as- prepared have been detected. Additionally, the coercivity of annealed sample shows one flipping point at 155 K where it behavior with temperature is changed. Meanwhile, the as-prepared sample show two flipped point at 205 K and 55 K. A mismatch between field cooling (FC) and field heating (FH) magnetization curves with temperature has been detected for annealed sample at low applied magnetic field. In addition the FC and FH curves shows different slopes with variation the temperature and the magnetic field. By increasing the external magnetic field higher than 200 Oe and up to 20 kOe a gradual changing in the magnetic behavior has been detected, where the mismatch and different slopes disappeared at applying magnetic field about 20 kOe. The difference in magnetic and structure behavior of Ni2FeSi microwires sample is discussed considering the effect of induced internal stresses by the presence of a glass coating and the recrystallization and stresses relaxation upon annealing. Materials science ; Coercivity ; Annealing (glass) ; Curie temperature ; Condensed matter physics ; Ferromagnetism ; Magnetic field ; Magnetization ; Monoclinic crystal system ; Analytical Chemistry (journal) ; Metallurgy ; Crystallography ; Chemistry ; Crystal structure ; Physics Heusler alloys: electronic and magnetic properties ; Shape Memory Alloy Transformations ; Magnetic properties of thin films
Authors: Zhicheng Jin | Yi Li | Ke Li | Jiajing Zhou | Justin Yeung | Chuxuan Ling | Wonjun Yim | Tengyu He | Yong Cheng | Ming Xu | Matthew N. Creyer | Yu‐Ci Chang | Pavla Fajtová | Maurice Retout | Baiyan Qi | Shuzhou Li | Anthony J. O’Donoghue | Jesse V. Jokerst
Source: Angewandte Chemie (article, 2022-11-21)
Field: Materials Science — Biomaterials

Peptide Amphiphile Mediated Co‐assembly for Nanoplasmonic Sensing Abstract Aromatic interactions are commonly involved in the assembly of naturally occurring building blocks, and these interactions can be replicated in an artificial setting to produce functional materials. Here we describe a colorimetric biosensor using co‐assembly experiments with plasmonic gold and surfactant‐like peptides (SLPs) spanning a wide range of aromatic residues, polar stretches, and interfacial affinities. The SLPs programmed in DDD−(ZZ) x −FFPC self‐assemble into higher‐order structures in response to a protease and subsequently modulate the colloidal dispersity of gold leading to a colorimetric readout. Results show the strong aggregation propensity of the FFPC tail without polar DDD head. The SLPs were specific to the target protease, i.e., M pro , a biomarker for SARS‐CoV‐2. This system is a simple and visual tool that senses M pro in phosphate buffer, exhaled breath condensate, and saliva with detection limits of 15.7, 20.8, and 26.1 nM, respectively. These results may have value in designing other protease testing methods. Protease ; Chemistry ; Amphiphile ; Dispersity ; Biosensor ; Nanotechnology ; Self-assembly ; Combinatorial chemistry ; Peptide ; Biophysics ; Materials science ; Biochemistry ; Enzyme ; Biology ; Polymer ; Organic chemistry Supramolecular Self-Assembly in Materials ; Advanced biosensing and bioanalysis techniques ; Polydiacetylene-based materials and applications
Authors: Zhentao Wang | Dominique Gautreau | Turan Birol | Rafael M. Fernandes
Source: Physical review. B./Physical review. B (article, 2022-04-05)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Strain-tunable metamagnetic critical endpoint in Mott insulating rare-earth titanates Rare-earth titanates are Mott insulators whose magnetic ground state---antiferromagnetic (AFM) or ferromagnetic (FM)---can be tuned by the radius of the rare-earth element. Here, we combine phenomenology and first-principles calculations to shed light on the generic magnetic phase diagram of a chemically substituted titanate on the rare-earth site that interpolates between an AFM and a FM state. Octahedral rotations present in these perovskites cause the AFM order to acquire a small FM component---and vice-versa---removing any multicritical point from the phase diagram. However, for a wide parameter range, a first-order metamagnetic transition line terminating at a critical endpoint survives inside the magnetically ordered phase. Like the liquid-gas transition, a Widom line emerges from the endpoint, characterized by enhanced fluctuations. In contrast to metallic FMs, this metamagnetic transition involves two symmetry-equivalent and insulating canted spin states. Moreover, instead of a magnetic field, we show that uniaxial strain can be used to tune this transition to zero temperature, inducing a quantum critical endpoint. Condensed matter physics ; Phase diagram ; Multicritical point ; Antiferromagnetism ; Materials science ; Quantum critical point ; Ferroelectricity ; Ferromagnetism ; Ground state ; Phase transition ; Metamagnetism ; Quantum phase transition ; Magnetic field ; Physics ; Phase (matter) ; Magnetization ; Quantum mechanics Magnetic and transport properties of perovskites and related materials ; Advanced Condensed Matter Physics ; Iron-based superconductors research
Authors: Tomasz Wróblewski | Dzmitryi Ushakou
Source: Journal of Fluorescence (article, 2022-10-22)
Field: Chemistry — Physical and Theoretical Chemistry

Stepwise Excited-state Double Proton Transfer and Fluorescence Decay Analysis This work considers excited state intramolecular proton transfers (ESIPT) occurred in multiple hydroxyl-containing compounds with one proton transfer site in the normal form. If several hydroxyl groups are located close to each other in a molecule, then the ESIPT process can lead to the next one. A proton donor site in the first ESIPT will be a proton acceptor during the second reaction. Therefore, a number of consecutive excited state proton transfers can occur. This work deals with the case of two successive proton transfers occurred in the molecular system. Such process is called as a stepwise excited state intramolecular double proton transfer (stepwise ESIDPT). It leads to the formation of two molecular tautomers. Therefore, fluorescence of such compounds can contain different emission bands correspond to emission of normal form and two tautomers. In this work, a rigorous analysis of fluorescence decay kinetics has been made using the model with three species, including a normal molecular form and two tautomers. The work presents theoretical framework of fluorescence decay analysis of ESIDPT process taking into account three species emission. Theoretically, the stepwise proton transfers can be consisted of more than two ESIPT reactions. It depends on molecular structure and number of involved hydroxyl groups. Here, a formal analysis of fluorescence decay kinetics has been made in the case of a stepwise process consisting of two proton transfers. Moreover, the quantum-chemical calculations have been performed in the case of scutellarein. It is a multiple hydroxyl-containing flavone and, therefore, it can be applied as a model molecule to study stepwise intramolecular proton transfers. The hypothetical scheme of ESIDPT has been proposed for this compound. Tautomer ; Chemistry ; Proton ; Excited state ; Intramolecular force ; Fluorescence ; Photochemistry ; Molecule ; Atomic physics ; Stereochemistry ; Organic chemistry Photochemistry and Electron Transfer Studies ; Porphyrin and Phthalocyanine Chemistry ; Free Radicals and Antioxidants
Authors: Ana S. Luís | Edwin A. Yates | Alan Cartmell
Source: Essays in Biochemistry (article, 2022-12-23)
Field: Chemistry — Organic Chemistry

Functions and specificity of bacterial carbohydrate sulfatases targeting host glycans Sulfated host glycans (mucin O-glycans and glycosaminoglycans [GAGs]) are critical nutrient sources and colonisation factors for Bacteroidetes of the human gut microbiota (HGM); a complex ecosystem comprising essential microorganisms that coevolved with humans to serve important roles in pathogen protection, immune signalling, and host nutrition. Carbohydrate sulfatases are essential enzymes to access sulfated host glycans and are capable of exquisite regio- and stereo-selective substrate recognition. In these enzymes, the common recognition features of each subfamily are correlated with their genomic and environmental context. The exo-acting carbohydrate sulfatases are attractive drug targets amenable to small-molecule screening and subsequent engineering, and their high specificity will help elucidate the role of glycan sulfation in health and disease. Inhibition of carbohydrate sulfatases provides potential routes to control Bacteroidetes growth and to explore the influence of host glycan metabolism by Bacteroidetes on the HGM ecosystem. The roles of carbohydrate sulfatases from the HGM organism Bacteroides thetaiotaomicron and the soil isolated Pedobacter heparinus (P. heparinus) in sulfated host glycan metabolism are examined and contrasted, and the structural features underpinning glycan recognition and specificity explored. Glycan ; Bacteroides thetaiotaomicron ; Biology ; Bacteroidetes ; Sulfation ; Biochemistry ; Microbiology ; Bacteria ; Bacteroides ; Genetics ; Glycoprotein ; Gene Carbohydrate Chemistry and Synthesis ; Glycosylation and Glycoproteins Research ; Proteoglycans and glycosaminoglycans research
Authors: Elvira Mahu | Petrişor Samoilă | Maria Ignat | Corneliu Cojocaru | Valeria Harabagiu
Source: Comptes Rendus Chimie (article, 2022-04-11)
Field: Materials Science — Materials Chemistry

Influence of fuel nature on sol–gel microwave-ignited combustion synthesis of nanosized cobalt and nickel spinel ferrites CoFe <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msub> </mml:math> O <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> and NiFe <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>2</mml:mn> </mml:msub> </mml:math> O <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mrow/> <mml:mn>4</mml:mn> </mml:msub> </mml:math> spinel ferrites were obtained by microwave-assisted sol–gel combustion synthesis using three different types of chelating/combustion agents: maleic acid, citric acid, and urea. The nanomaterials produced were characterized from the structural, morphological, textural, and magnetic viewpoints. The spinel ferrites prepared were employed as adsorbents for the removal of Orange-II dye from synthetic wastewaters. The nickel ferrite sample prepared using urea as fuel exhibited distinctive properties such as the smallest crystallite size and the highest specific surface area. Likewise, this material was the most efficient for the adsorption of the organic pollutant (50.32 mg/g) from aqueous solutions. Spinel ; Nuclear chemistry ; Chemistry ; Nickel ; Specific surface area ; Cobalt ; Combustion ; Urea ; Adsorption ; Mineralogy ; Inorganic chemistry ; Materials science ; Metallurgy ; Organic chemistry ; Catalysis Magnetic Properties and Synthesis of Ferrites ; Nanomaterials for catalytic reactions ; Advancements in Battery Materials
Authors: Alexander Pomberger | Antonio Pedrina McCarthy | Ahmad Khan | Simon Sung | Connor J. Taylor | Matthew J. Gaunt | Lucy J. Colwell | D. Walz | Alexei A. Lapkin
Source: ChemRxiv (preprint, 2022-01-17)
Field: Materials Science — Materials Chemistry

The Effect of Chemical Representation on Active Machine Learning Towards Closed-Loop Optimization Multivariate chemical reaction optimization involving catalytic systems is a non-trivial task due to the high number of tuneable parameters and discrete choices. Closed-loop optimization featuring active Machine Learning (ML) represents a powerful strategy for automating reaction optimization. However, the translation of chemical reaction conditions into a machine-readable format comes with the challenge of finding highly informative features which accurately capture the factors for reaction success and allow the model to learn efficiently. Herein, we compare the efficacy of different calculated chemical descriptors for a high throughput generated dataset to determine the impact on a supervised ML model when predicting reaction yield. Then, the effect of featurization and size of the initial dataset within a closed-loop reaction optimization was examined. Finally, the balance between descriptor complexity and dataset size was considered. Ultimately, tailored descriptors did not outperform simple generic representations, however, a larger initial dataset accelerated reaction optimization. Computer science ; Machine learning ; Representation (politics) ; Artificial intelligence ; Throughput ; Multivariate statistics ; Task (project management) ; Closed loop ; Simple (philosophy) ; Engineering Machine Learning in Materials Science ; Computational Drug Discovery Methods
Authors: Jason Hattrick‐Simpers | Kangming Li | Michael Greenwood | Robert W. Black | Julia Witt | Mark Kozdras | Xin Pang | Özlem Özcan
Source: Cell Reports Physical Science (article, 2022-12-16)
Field: Materials Science — Materials Chemistry

Designing durable, sustainable, high-performance materials for clean energy infrastructure Civilization and modern societies would not be possible without manmade materials. Considering their production volumes, their supporting role in nearly all industrial processes, and the impact of their sourcing and production on the environment, metals and alloys are and will be of prominent importance for the clean energy transition. The focus of materials discovery must move to more specialized, application-tailored green alloys that outperform the legacy materials not only in performance but also in sustainability and resource efficiency. This white paper summarizes a joint Canadian-German initiative aimed at developing a materials acceleration platform (MAP) focusing on the discovery of new alloy families that will address this challenge. We call our initiative the “Build to Last Materials Acceleration Platform” (B2L-MAP) and present in this perspective our concept of a three-tiered self-driving laboratory that is composed of a simulation-aided pre-selection module (B2L-select), an artificial intelligence (AI)-driven experimental lead generator (B2L-explore), and an upscaling module for durability assessment (B2L-assess). The resulting tool will be used to identify and subsequently demonstrate novel corrosion-resistant alloys at scale for three key applications of critical importance to an offshore, wind-driven hydrogen plant (reusable electrical contacts, offshore infrastructure, and oxygen evolution reaction catalysts). Sustainability ; Computer science ; Efficient energy use ; Scale (ratio) ; Production (economics) ; Systems engineering ; Environmental science ; Engineering Machine Learning in Materials Science ; Electron and X-Ray Spectroscopy Techniques ; Technology Assessment and Management
Authors: Amy E. Barton | Gerrit Borchard | Matthias G. Wacker | Giorgia Pastorin | Imran Saleem | Shaqil H. Chaudary | Tamer Elbayoumi | Zhigang Zhao | Beat Flühmann
Source: Pharmacy (article, 2022-01-21)
Field: Materials Science — Biomaterials

Need for Expansion of Pharmacy Education Globally for the Growing Field of Nanomedicine The emerging landscape of nanomedicine includes a wide variety of active pharmaceutical ingredients and drug formulations. Their design provides nanomedicines with unique features leading to improved pharmacokinetics and pharmacodynamics. They are manufactured using conventional or biotechnological manufacturing processes. Their physical characteristics are vastly different from traditional small-molecule drugs. Pharmacists are important members of the multi-disciplinary team of scientists involved in their development and clinical application. Consequently, their training should lead to an understanding of the complexities associated with the production and evaluation of nanomedicines. Therefore, student pharmacists, post-doctoral researchers, and trainees should be given more exposure to this rapidly evolving class of therapeutics. This commentary will provide an overview of nanomedicine education within the selection of pharmacy programs globally, discuss the current regulatory challenges, and describe different approaches to incorporate nanomedicine science in pharmacy programs around the world. Nanomedicine ; Pharmacy ; Variety (cybernetics) ; Medicine ; Engineering ethics ; Pharmacology ; Nanotechnology ; Engineering ; Computer science ; Nursing ; Materials science Nanoparticle-Based Drug Delivery ; Nanoparticles: synthesis and applications ; Nanotechnology research and applications