jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ashit Rao | Markus Drechsler | Stefan Schiller | Martin Scheffner | Denis Gebauer | Helmut Cölfen
Source: Advanced Functional Materials (article, 2018-07-25)
Field: Materials Science — Biomaterials

Stabilization of Mineral Precursors by Intrinsically Disordered Proteins Abstract Biogenic nucleation and crystallization occur in confined spaces with defined interfacial properties. However, the regulatory functions of organic players in the stabilization and transport of inorganic precursors such as ion clusters, liquid‐condensed phases, and amorphous particles are unclear. Given the prevalence of unstructured proteins in biogenic materials, the present study investigates the effects of biomineral‐associated, intrinsically disordered protein domains with simple and repetitive amino acid compositions on mineral nucleation and their capability to form distinct supramolecular assemblies. The quantitative assessment and structural evaluation of the nucleation process reveal that disordered regions confine hydrated mineral precursors within vesicles, transiently suppressing mineral precipitation. Stabilization of the amorphous mineral is attributed to protein self‐association and restructuration toward β‐configurations, triggered by specific bioinorganic interactions. In consequence, the conditioned macromolecules localize at phase boundaries formed upon liquid–liquid demixing of mineral precursors and stabilize the fluidic mineral precursors against crystallization. Thus, the conformational plasticity and self‐association of intrinsically disordered sequences in response to crystallization environments mediates the selection of functional macromolecular subensembles dedicated to biomaterial growth. Nucleation ; Biomineralization ; Crystallization ; Materials science ; Macromolecule ; Mineral ; Intrinsically disordered proteins ; Amorphous solid ; Chemical physics ; Phase (matter) ; Protein crystallization ; Biophysics ; Crystallography ; Chemical engineering ; Chemistry ; Biochemistry ; Organic chemistry ; Biology Calcium Carbonate Crystallization and Inhibition ; Bone Tissue Engineering Materials ; Paleontology and Stratigraphy of Fossils
Authors: Claudio Corgnale | Martin Sulic
Source: Metals (article, 2018-06-20)
Field: Materials Science — Materials Chemistry

Techno-Economic Analysis of High-Pressure Metal Hydride Compression Systems Traditional high-pressure mechanical compressors account for over half of the car station’s cost, have insufficient reliability, and are not feasible for a large-scale fuel cell market. An alternative technology, employing a two-stage, hybrid system based on electrochemical and metal hydride compression technologies, represents an excellent alternative to conventional compressors. The high-pressure stage, operating at 100–875 bar, is based on a metal hydride thermal system. A techno-economic analysis of the metal hydride system is presented and discussed. A model of the metal hydride system was developed, integrating a lumped parameter mass and energy balance model with an economic model. A novel metal hydride heat exchanger configuration is also presented, based on minichannel heat transfer systems, allowing for effective high-pressure compression. Several metal hydrides were analyzed and screened, demonstrating that one selected material, namely (Ti0.97Zr0.03)1.1Cr1.6Mn0.4, is likely the best candidate material to be employed for high-pressure compressors under the specific conditions. System efficiency and costs were assessed based on the properties of currently available materials at industrial levels. Results show that the system can reach pressures on the order of 875 bar with thermal power provided at approximately 150 °C. The system cost is comparable with the current mechanical compressors and can be reduced in several ways as discussed in the paper. Gas compressor ; Hydride ; Nuclear engineering ; Heat exchanger ; Process engineering ; Mechanical engineering ; Engineering ; Materials science ; Metal ; Metallurgy Hydrogen Storage and Materials ; Nuclear Materials and Properties ; Ammonia Synthesis and Nitrogen Reduction
Authors: Jakob Wirbel | Pedro R. Cutillas | Julio Sáez-Rodríguez
Source: Methods in molecular biology (article, 2018-01-01)
Field: Chemistry — Spectroscopy

Phosphoproteomics-Based Profiling of Kinase Activities in Cancer Cells Cellular signaling, predominantly mediated by phosphorylation through protein kinases, is found to be deregulated in most cancers. Accordingly, protein kinases have been subject to intense investigations in cancer research, to understand their role in oncogenesis and to discover new therapeutic targets. Despite great advances, an understanding of kinase dysfunction in cancer is far from complete.A powerful tool to investigate phosphorylation is mass-spectrometry (MS)-based phosphoproteomics, which enables the identification of thousands of phosphorylated peptides in a single experiment. Since every phosphorylation event results from the activity of a protein kinase, high-coverage phosphoproteomics data should indirectly contain comprehensive information about the activity of protein kinases.In this chapter, we discuss the use of computational methods to predict kinase activity scores from MS-based phosphoproteomics data. We start with a short explanation of the fundamental features of the phosphoproteomics data acquisition process from the perspective of the computational analysis. Next, we briefly review the existing databases with experimentally verified kinase-substrate relationships and present a set of bioinformatic tools to discover novel kinase targets. We then introduce different methods to infer kinase activities from phosphoproteomics data and these kinase-substrate relationships. We illustrate their application with a detailed protocol of one of the methods, KSEA (Kinase Substrate Enrichment Analysis). This method is implemented in Python within the framework of the open-source Kinase Activity Toolbox (kinact), which is freely available at http://github.com/saezlab/kinact/ . Phosphoproteomics ; Kinase ; Computational biology ; Phosphorylation ; Proteomics ; Biology ; Protein phosphorylation ; Bioinformatics ; Protein kinase A ; Computer science ; Cell biology ; Biochemistry Advanced Proteomics Techniques and Applications ; Enzyme Structure and Function ; Metabolomics and Mass Spectrometry Studies
Authors: Sher Bahadar Khan | Khalid A. Alamry | Nedaa A. Alyahyawi | Abdullah M. Asiri
Source: International Journal of Nanomedicine (article, 2018-05-01)
Field: Materials Science — Materials Chemistry

Controlled release of organic&amp;ndash;inorganic nanohybrid:cefadroxil intercalated Zn&amp;ndash;Al-layered double hydroxide This material might reduce side effects by the release of the drug in a controlled manner. However, it was found that the presence of Cl or PAM species in the release media has a negative impact on the release behavior. The weathering mechanism is responsible for the release of CD from the nanocomposite at pH 1.2, while the mechanism of anion exchange may be responsible for the release behavior at pH 4.0, 6.8 and 7.4. A number of kinetic models were chosen to gain more insights into the mechanisms of drug release. At pH 1.2, the zero-order model most satisfactorily explained the release kinetics of CD, while the release data of CD at pH 4.0, 6.8 and 7.4 were governed by Bhaskar kinetics. Fourier transform infrared spectroscopy ; Nuclear chemistry ; Thermogravimetric analysis ; Intercalation (chemistry) ; Hydroxide ; Controlled release ; Materials science ; Chemistry ; Inorganic chemistry ; Chemical engineering ; Organic chemistry ; Nanotechnology Layered Double Hydroxides Synthesis and Applications ; Magnesium Oxide Properties and Applications ; Advanced Photocatalysis Techniques
Authors: Muntazim Munir Khan | Karabi Halder | Sergey Shishatskiy | Volkan Filiz
Source: Polymers (article, 2018-02-23)
Field: Materials Science — Polymers and Plastics

Synthesis and Crosslinking of Polyether-Based Main Chain Benzoxazine Polymers and Their Gas Separation Performance The poly(ethylene glycol)-based benzoxazine polymers were synthesized via a polycondensation reaction between Bisphenol-A, paraformaldehyde, and poly(ether diamine)/(Jeffamine<sup>®</sup>). The structures of the polymers were confirmed by proton nuclear magnetic resonance spectroscopy (¹H-NMR), indicating the presence of a cyclic benzoxazine ring. The polymer solutions were casted on the glass plate and cross-linked via thermal treatment to produce tough and flexible films without using any external additives. Thermal properties and the crosslinking behaviour of these polymers were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Single gas (H₂, O₂, N₂, CO₂, and CH₄) transport properties of the crosslinked polymeric membranes were measured by the time-lag method. The crosslinked PEG-based polybenzoxazine membranes show improved selectivities for CO₂/N₂ and CO₂/CH₄ gas pairs. The good separation selectivities of these PEG-based polybenzoxazine materials suggest their utility as efficient thin film composite membranes for gas and liquid membrane separation technology. Polymer ; Chain (unit) ; Gas separation ; Materials science ; Polymer science ; Separation (statistics) ; Chemical engineering ; Polymer chemistry ; Chemistry ; Composite material ; Computer science ; Engineering ; Membrane Synthesis and properties of polymers ; Epoxy Resin Curing Processes ; Membrane Separation and Gas Transport
Authors: Evan P. Troendle | Ayesha Khan | Peter C. Searson | Martin B. Ulmschneider
Source: Journal of Controlled Release (article, 2018-11-08)
Field: Materials Science — Biomaterials

Predicting drug delivery efficiency into tumor tissues through molecular simulation of transport in complex vascular networks Drug delivery ; Doxorubicin ; Pharmacokinetics ; Drug ; Distribution (mathematics) ; Biomedical engineering ; Pharmacology ; Computer science ; Medicine ; Nanotechnology ; Materials science ; Chemotherapy ; Surgery ; Mathematics Nanoparticle-Based Drug Delivery ; Mathematical Biology Tumor Growth ; Microfluidic and Capillary Electrophoresis Applications
Authors: А. А. Назаров
Source: Letters on Materials (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Nonequilibrium grain boundaries in bulk nanostructured metals and their recovery under the influences of heating and cyclic deformation. Review Bulk nanostructured, or ultrafine-grained (UFG) metals and alloys produced by severe plastic deformation (SPD) methods have grain boundaries (GBs), which are in a specific, non-equilibrium state associated with extrinsic grain boundary dislocations (EGBDs) introduced into the boundaries during deformation. In the present review, the origin of this state is analyzed basing on the results of studies of large plastic deformations, according to which during straining the GBs accumulate mesodefects consisting of Rybin disclinations at triple junctions and tangential EGBD arrays and inherit them after removing the load. The main experimental evidences of the nonequilibrium character of GBs in as-prepared nanostructured materials are presented. Main ideas and results of the structural model of UFG metals based on the physics of dislocations and disclinations are overviewed. The latest works on molecular dynamics simulations carried out to explore the detailed atomic structure of disclinations and nonequilibrium GBs are considered and their results are compared to the predictions of the structural model. Mechanisms and kinetics of diffusion controlled recovery of nonequilirium GBs are described. An alternative mechanism of athermal relaxation of nonequilirium GB structure under the action of oscillating stresses has been most recently discovered and elucidated experimentally and by means of computer simulations. The main results of these studies are shortly reviewed too. Materials science ; Grain boundary ; Non-equilibrium thermodynamics ; Relaxation (psychology) ; Deformation (meteorology) ; Diffusion ; Severe plastic deformation ; Deformation mechanism ; Condensed matter physics ; Grain Boundary Sliding ; Molecular dynamics ; Grain size ; Chemical physics ; Metallurgy ; Thermodynamics ; Composite material ; Microstructure ; Physics Microstructure and mechanical properties ; Material Properties and Failure Mechanisms ; Surface Treatment and Residual Stress
Authors: Xi Chen | Yao‐Wen Wu
Source: Angewandte Chemie International Edition (article, 2018-04-11)
Field: Materials Science — Materials Chemistry

Tunable and Photoswitchable Chemically Induced Dimerization for Chemo‐optogenetic Control of Protein and Organelle Positioning Abstract The spatiotemporal dynamics of proteins and organelles play an important role in controlling diverse cellular processes. Optogenetic tools using photosensitive proteins and chemically induced dimerization (CID), which allow control of protein dimerization, have been used to elucidate the dynamics of biological systems and to dissect the complicated biological regulatory networks. However, the inherent limitations of current optogenetic and CID systems remain a significant challenge for the fine‐tuning of cellular activity at precise times and locations. Herein, we present a novel chemo‐optogenetic approach, photoswitchable chemically induced dimerization (psCID), for controlling cellular function by using blue light in a rapid and reversible manner. Moreover, psCID is tunable; that is, the dimerization and dedimerization degrees can be fine‐tuned by applying different doses of illumination. Using this approach, we control the localization of proteins and positioning of organelles in live cells with high spatial (μm) and temporal (ms) precision. Optogenetics ; Organelle ; Biophysics ; Chemistry ; Synthetic biology ; Nanotechnology ; Materials science ; Biology ; Computational biology ; Neuroscience ; Biochemistry Photochromic and Fluorescence Chemistry ; Photoreceptor and optogenetics research ; Polydiacetylene-based materials and applications
Authors: Martin Prostredný | Mohammed G. M. Abduljalil | Paul A. Mulheran | Ashleigh J. Fletcher
Source: Gels (article, 2018-04-17)
Field: Chemistry — Spectroscopy

Process Variable Optimization in the Manufacture of Resorcinol–Formaldehyde Gel Materials Influence of process parameters of resorcinol⁻formaldehyde xerogel manufacture on final gel structure was studied, including solids content, preparation/drying temperature, solvent exchange, and drying method. Xerogels produced using a range of solids content between 10 and 40 <i>w</i>/<i>v</i>% show improved textural character up to 30 <i>w</i>/<i>v</i>% with a subsequent decrease thereafter. Preparation/drying temperature shows a minimal threshold temperature of 55 °C is required to obtain a viable gel structure, with minimal impact on gel properties for further thermal increase. Improving the solvent exchange method by splitting the same amount of acetone used in this phase over the period of solvent exchange, rather than in a single application, shows an increase in total pore volume and average pore diameter, suggesting less shrinkage occurs during drying when using the improved method. Finally, comparing samples dried under vacuum and at ambient pressure, there seems to be less shrinkage when using vacuum drying compared to ambient drying, but these changes are insubstantial. Therefore, of the process parameters investigated, improved solvent exchange seems the most significant, and it is recommended that, economically, gels are produced using a solids content of 20 <i>w</i>/<i>v</i>% at a minimum temperature of 55 °C, with regular solvent replenishment in the exchange step, followed by ambient drying. Solvent ; Shrinkage ; Resorcinol ; Volume (thermodynamics) ; Materials science ; Formaldehyde ; Acetone ; Chemical engineering ; Vacuum drying ; Phase (matter) ; Chromatography ; Chemistry ; Composite material ; Freeze-drying ; Organic chemistry ; Thermodynamics Aerogels and thermal insulation ; Pigment Synthesis and Properties
Authors: Juan L. Paris | Gonzalo Villaverde | M.V. Cabañas | Miguel Manzano | María Vallet‐Regí
Source: Journal of Materials Chemistry B (article, 2018-01-01)
Field: Materials Science — Biomaterials

From proof-of-concept material to PEGylated and modularly targeted ultrasound-responsive mesoporous silica nanoparticles In this work we present the synthesis, characterization and in vitro biological evaluation of PEGylated and actively-targeted ultrasound-responsive hybrid mesoporous silica nanoparticles. This work covers the development of the chemical strategies necessary to afford a modular nanocarrier starting from a proof-of-concept material presented in previous work. This functional ultrasound-responsive material can be adapted to different specific pathological conditions by carefully choosing the appropriate targeting moieties. The new ultrasound responsive material is able to target HeLa cells when conjugated with biotin or an RGD peptide. Ultrasound-responsive cytotoxicity towards cancer cells of doxorubicin-loaded nanoparticles is demonstrated in an in vitro cytotoxicity assay. Nanocarriers ; Mesoporous silica ; Nanoparticle ; Materials science ; Doxorubicin ; HeLa ; Nanotechnology ; Cytotoxicity ; Ultrasound ; Conjugated system ; In vitro ; Mesoporous material ; Chemistry ; Biochemistry ; Medicine ; Polymer Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; Graphene and Nanomaterials Applications
Authors: Zakariya Dalala | Osama Saadeh | Mathhar Bdour | Zaka Ullah Zahid
Source: Energies (article, 2018-07-12)
Field: Materials Science — Materials Chemistry

A New Maximum Power Point Tracking (MPPT) Algorithm for Thermoelectric Generators with Reduced Voltage Sensors Count Control † This paper proposes a new maximum power point tracking (MPPT) algorithm for thermoelectric generators (TEG). The new-presented method is based on implementing an indirect open circuit voltage detection and short circuit current estimation methods, which will be used to directly control the TEG interface power converter, resulting in reaching the maximum power point (MPP) in minimal number of steps. Two modes of operation are used in the proposed algorithm, namely the perturb and observe (P&amp;O) method for fine-tuning and the transient mode for coarse tracking of the MPP during fast changes that occur to the temperature gradient across the structure. A novel voltage sensing technique as well is proposed in this work, to reduce the number of voltage sensors used to control and monitor the power converter. The proposed strategy employs a novel approach to sense two different voltages using the same voltage sensor. The input and output voltage information is collected from an intermediate point in the converter. The reconstructed voltages are used in the control loops as well as for monitoring the battery output or load voltages. Simulation and experimental results are provided to validate the effectiveness of the proposed algorithm and the sensing technique. Maximum power point tracking ; Voltage ; Maximum power principle ; Power (physics) ; Computer science ; Control theory (sociology) ; Battery (electricity) ; Sense (electronics) ; Point (geometry) ; Voltage reference ; Algorithm ; Electronic engineering ; Engineering ; Electrical engineering ; Mathematics ; Control (management) ; Physics Advanced Thermoelectric Materials and Devices ; Innovative Energy Harvesting Technologies ; Energy Harvesting in Wireless Networks
Authors: Cecilia Granados‐Miralles | Matilde Saura‐Múzquiz | H.L. Andersen | Adrián Quesada | Jakob Voldum Ahlburg | Ann‐Christin Dippel | Emmanuel Canévet | Mogens Christensen
Source: ACS Applied Nano Materials (article, 2018-06-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Approaching Ferrite-Based Exchange-Coupled Nanocomposites as Permanent Magnets During the past decade, CoFe<sub>2</sub>O<sub>4</sub> (hard)/Co-Fe alloy (soft) magnetic nanocomposites have been routinely prepared by partial reduction of CoFe<sub>2</sub>O<sub>4</sub> nanoparticles. Monoxide (i.e., FeO or CoO) has often been detected as a byproduct of the reduction, although it remains unclear whether the formation of this phase occurs during the reduction itself or at a later stage. Here, a novel reaction cell was designed to monitor the reduction <i>in situ</i> using synchrotron powder X-ray diffraction (PXRD). Sequential Rietveld refinements of the <i>in situ</i> data yielded time-resolved information on the sample composition and confirmed that the monoxide is generated as an intermediate phase. The macroscopic magnetic properties of samples at different reduction stages were measured by means of vibrating sample magnetometry (VSM), revealing a magnetic softening with increasing soft phase content, which was too pronounced to be exclusively explained by the introduction of soft material in the system. The elemental compositions of the constituent phases were obtained from joint Rietveld refinements of <i>ex situ</i> high-resolution PXRD and neutron powder diffraction (NPD) data. It was found that the alloy has a tendency to emerge in a Co-rich form, inducing a Co deficiency on the remaining spinel phase, which can explain the early softening of the magnetic material. Magnet ; Nanocomposite ; Ferrite (magnet) ; Materials science ; Neodymium magnet ; Composite material ; Metallurgy ; Mechanical engineering ; Engineering Magnetic Properties of Alloys ; Advancements in Battery Materials ; Magnetic Properties and Synthesis of Ferrites
Authors: Wiktor Beker | Ewa Gajewska | Tomasz Badowski | Bartosz A. Grzybowski
Source: Angewandte Chemie (article, 2018-11-06)
Field: Materials Science — Materials Chemistry

Prediction of Major Regio‐, Site‐, and Diastereoisomers in Diels–Alder Reactions by Using Machine‐Learning: The Importance of Physically Meaningful Descriptors Abstract Machine learning can predict the major regio‐, site‐, and diastereoselective outcomes of Diels–Alder reactions better than standard quantum‐mechanical methods and with accuracies exceeding 90 % provided that i) the diene/dienophile substrates are represented by “physical‐organic” descriptors reflecting the electronic and steric characteristics of their substituents and ii) the positions of such substituents relative to the reaction core are encoded (“vectorized”) in an informative way. Steric effects ; Diastereomer ; Diene ; Diels–Alder reaction ; Chemistry ; Core (optical fiber) ; Computational chemistry ; Quantum chemical ; Stereochemistry ; Organic chemistry ; Computer science ; Molecule ; Catalysis Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Various Chemistry Research Topics