The relationship between properties of plant-based biochars and sorption of Cd(II), Pb(II) and Zn(II) in soil model systems

AbstractScaffold proteins are thought to accelerate protein phosphorylation reactions by tethering kinases and substrates together, but there is little quantitative data on their functional effects. To assess the contribution of tethering to kinase reactivity, we compared intramolecular and intermolecular kinase reactions in a minimal model system. We find that tethering can enhance reaction rates in a flexible tethered kinase system, and the magnitude of the effect is sensitive to the structure of the tether. The largest effective molarity we obtained was ∼0.08 µM, which is much lower than the effects observed in small molecule model systems and tethered protein-ligand interactions. We further demonstrate that the tethered, intramolecular reaction only makes a significant contribution to observed rates when the scaffolded complex assembles at concentrations below the effective molarity. These findings provide a quantitative framework that can be applied to understand endogenous protein scaffolds and to engineer synthetic networks.

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Anthenes: Model systems for understanding the edge state of graphene nanoribbons

Pure and Applied Chemistry ◽

10.1515/pac-2013-0811 ◽

2014 ◽

Vol 86 (4) ◽

pp. 497-505 ◽

Cited By ~ 13

Author(s):

Akihito Konishi ◽

Yasukazu Hirao ◽

Hiroyuki Kurata ◽

Takashi Kubo ◽

Masayoshi Nakano ◽

...

Keyword(s):

Molecular Structure ◽

Electron Correlation ◽

Magnetic State ◽

Graphene Nanoribbons ◽

Edge State ◽

Model Systems ◽

The Relationship ◽

Π State

AbstractThe edge state, which is a peculiar magnetic state in zigzag-edged graphene nanoribbons (ZGNRs) originating from an electron–electron correlation in an edge-localized π-state, has promising applications for magnetic and spintronics devices and has attracted much attention of physicists, chemists, and engineers. For deeper understanding of the edge state, precise fabrication of edge structures in ZGNRs has been highly demanded. We focus on anthenes, which are peri-condensed anthracenes that have zigzag and armchair edges on the molecular periphery, as model systems for understanding, and indeed prepare and characterize them. This paper summarizes our recent studies on the origin of the edge state by investigating anthenes in terms of the relationship between the molecular structure and spin-localizing character.

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Study on Fundamental Frequency of Airport Runway Based on Elastic Layered Soil Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.851.643 ◽

2016 ◽

Vol 851 ◽

pp. 643-648

Author(s):

Liang Liang ◽

Yong Sheng Hou

Keyword(s):

Fundamental Frequency ◽

Coupling Effect ◽

Layered Soil ◽

Research Results ◽

Soil Model ◽

Airport Runway ◽

The Relationship

The relationship between fundamental frequency and structural layerof runway is discussed based on a series of ANSYS models. The research results indicate that the coupling effect of runway plates on fundamental frequency could not be neglected. According to the analysis on fundamental frequency of runways of different sizes, an area of 45m times 15m affects fundamental frequency the least. Thickness and strength of the base significantly affects fundamental frequency. Fundamental frequency of runway ranges from6.8Hz to 25.6 Hz.

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Comparative Phytotoxicity Assays of the Herbicide Alloxydim and Its Main Identified Photoproduct in Cereal and Broadleaves Crops

Weed Science ◽

10.1614/ws-d-14-00122.1 ◽

2015 ◽

Vol 63 (2) ◽

pp. 377-387 ◽

Cited By ~ 2

Author(s):

Pilar Sandín-España ◽

Beatriz Sevilla-Morán ◽

Mercedes Villarroya-Ferruz ◽

José L. Alonso-Prados ◽

M. Inés Santín-Montanyá

Keyword(s):

Human Health ◽

Active Substance ◽

Degradation Products ◽

Model Systems ◽

Parent Substance ◽

Cereal Crops ◽

Rapid Degradation ◽

Soil Model ◽

Plant Cuticles ◽

Grass Weed

When herbicides are sprayed in the field, a proportion of the herbicide falls onto leaves and soil surfaces, where it can be exposed to sunlight, generating photoproducts that can be more toxic and/or persistent than the parent substance and affect human health and the environment. The aim of this study was to identify the photoproducts of the herbicide alloxydim in leaf and soil model systems and to perform phytotoxicity studies. Alloxydim was rapidly photodegraded in systems simulating plant cuticles and soil surfaces, with half-lives ranging from 1 to 30 min. The main by-product, identified by LC-Qtof-MS as deallyoxylated alloxydim, was more stable than the active substance. The EC50values on root lengths of different varieties of wheat plants and one grass weed ranged from 0.38 to 0.50 mg L−1for alloxydim. In contrast, the EC50values for deallyoxylated alloxydim ranged from 94 to 600 mg L−1in the same species and in crops where the herbicide was applied. Special attention should be given to alloxydim degradation products because of the rapid degradation of this herbicide. Comparative bioassay studies between alloxydim and its photostable by-product showed that the by-product presents low phytotoxicity, whereas alloxydim can cause injury to neighboring and succeeding cereal crops.

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Relationship between direct-potentiometric and flame-photometric measurement of sodium in blood.

Clinical Chemistry ◽

10.1093/clinchem/28.9.1931 ◽

1982 ◽

Vol 28 (9) ◽

pp. 1931-1935 ◽

Cited By ~ 22

Author(s):

F S Apple ◽

D D Koch ◽

S Graves ◽

J H Ladenson

Keyword(s):

Water Content ◽

Model Systems ◽

Develop Model ◽

Water Binding ◽

Ph Dependency ◽

Calibration Problem ◽

Human Sera ◽

Photometric Measurements ◽

Measurement Artifact ◽

The Relationship

Abstract The relationship between direct-potentiometric and flame-photometric measurements of sodium has been studied in human sera and other, simpler systems. When water content was varied by using an inert substance (silica), de-ionized sera, or de-ionized individual proteins, the percentage that the flame photometric values were of the direct potentiometric Na+ values was identical to the measured water content. However, in 35 patients the percentage of Na+ values was 99.1% and the water content was 92.0%, a discrepancy of 7.1%. De-ionization of sera removed this discrepancy, apparently because of the lower pH of the de-ionized sera. The percentage of flame-photometric to direct-potentiometric Na+ values varied as a function of pH in pooled sera; in lyophilized and reconstituted sera; and in de-ionized, lyophilized, and reconstituted sera. Four explanations for the discrepancy between the percentage of Na+ values and the water content are discussed: a calibration problem, a measurement artifact, Na+ binding, and water binding. At this time there are no definitive data concerning which explanation is correct. We expect that our finding of a pH dependency for the percentage of measured Na+ values can be used to develop model systems to elucidate the mechanism producing the discrepancy between the percentage of Na+ values and the water content.

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Size Dependent Interactions of Nanoparticles with Lung Surfactant Model Systems and the Significant Impact on Surface Potential

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.171 ◽

2008 ◽

Vol 8 (6) ◽

pp. 2971-2978 ◽

Cited By ~ 16

Author(s):

Tabitha Ku ◽

Simardeep Gill ◽

Raimar Löbenberg ◽

Shirzad Azarmi ◽

Wilson Roa ◽

...

Keyword(s):

Surface Potential ◽

Surface Pressure ◽

High Surface ◽

Lung Surfactant ◽

Drug Carriers ◽

Model Systems ◽

Optimal Size ◽

Surfactant Film ◽

Pressure Area ◽

The Relationship

The relationship between a model pulmonary surfactant system and various sized nanoparticles was investigated in this study. Diplamitoylphosphatidylcholine (DPPC) is the main lipid constituent of lung surfactant and has the ability to reach very high surface pressures (around 70 mN/m) upon compression. Due to these properties it was used as a model to simulate the lung surfactant film in vitro. The first objective of this study was to investigate the relationship between DPPC and various sized nanoparticles within the subphase through surface pressure—area isotherms. The second objective was to measure the surface potential of the different preparations (conducted on a mini-Langmuir trough) and to determine if an optimal nanoparticle size exists possessing a greater affinity for the DPPC film compared to other sizes. The results from the pressure area isotherms indicate that the interaction between DPPC and the nanoparticles is stable and that the 235 nm particles may represent an optimal size. Furthermore, the results from the surface potential experiments confirm that an interaction of the nanoparticles with the monolayer exists as indicated by surface-pressure area isotherms. Any even moderate interaction between nanoparticles and lung surfactant film might reduce or increase the surface potential of the surfactant film, and this might impact the deposition of the nanoparticles or other ligands which may be positively or negatively charged drugs within the surfactant film. Thus changes in surface potential due to nanoparticle interactions have to be taken into account for future drug targeting studies using nano-sized drug carriers.

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CRISPR-Cas-mediated tethering recruits the yeast HMR mating-type locus to the nuclear periphery but fails to silence gene expression

10.1101/2021.04.30.442211 ◽

2021 ◽

Author(s):

Emily R Cliff ◽

Robin L Kirkpatrick ◽

Daniel Cunningham-Bryant ◽

Brianna Fernandez ◽

Jesse G Zalatan

Keyword(s):

Gene Expression ◽

Genome Structure ◽

Nuclear Periphery ◽

Model Systems ◽

Type Locus ◽

Synthetic Genome ◽

Structural Differences ◽

And Function ◽

The Relationship ◽

Silence Gene

To investigate the relationship between genome structure and function, we have developed a programmable CRISPR-Cas system for nuclear peripheral recruitment in yeast. We benchmarked this system at the HMR and GAL2 loci, both well-characterized model systems for localization to the nuclear periphery. Using microscopy and gene silencing assays, we demonstrate that CRISPR-Cas-mediated tethering can recruit the HMR locus but does not silence reporter gene expression. A previously reported Gal4-mediated tethering system does silence gene expression, and we demonstrate that the silencing phenotype has an unexpected dependence on the structure of the protein tether. The CRISPR-Cas system was unable to recruit GAL2 to the nuclear periphery. Our results reveal potential challenges for synthetic genome structure perturbations and suggest that distinct functional effects can arise from subtle structural differences in how genes are recruited to the periphery.

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The influence of the moisture content of raw materials on the structuring of the extrudates

Potravinarstvo Slovak Journal of Food Sciences ◽

10.5219/1189 ◽

2019 ◽

Vol 13 (1) ◽

pp. 898-905

Author(s):

Davit Tsagareishvili ◽

Otari Sesikashvili ◽

Gia Dadunashvili ◽

Nugzari Sakhanberidze ◽

Shalva Tsagareishvili

Keyword(s):

Moisture Content ◽

Porous Structure ◽

Modulus Of Elasticity ◽

Raw Materials ◽

Amorphous State ◽

Model Systems ◽

Starch Gelatinization ◽

Embrittlement Temperature ◽

The One ◽

The Relationship

The article presents the results of studies on the model systems of extrudates conducted with a view to determining the function of moisture during the process of forming the structure of starch pastes. There was studied the influence of the moisture content of raw materials on a starch gelatinization point. Studies showed that 15% moisture content in raw materials is sufficient for its constituent phase – starch gelatinization, as well as for the transition of the whole mass to a fluid-viscous state. Further increase in the moisture content is accompanied by a decrease in a gelatinization point. In order to study the influence of moisture on the formation of a porous structure of extrudates, we studied the relationship between the different-type starch pastes and the degree of its transparency and its embrittlement temperature. It has been found that during the process of thermal and mechanical impacts, there occurs the process of the formation of a structure of starch pastes, in particular, samples with the different moisture contents can have an amorphous or crystalline structure. There has been established the relationship between the moisture content of raw materials on the modulus of elasticity of starch pastes based on them. The modulus of elasticity of samples was determined one hour (cooling time to room temperature) and one week after obtaining the starch paste. The above studies showed that minimal physico-chemical and mechanical transformations occur in starch pastes, which are in an amorphous state, that is, in the conditions of a low moisture content. We have established that the moisture content of raw materials, on the one hand, ensures the transition of a high-dispersive phase to a fluid state, or implementing the ex process of extrusion, and on the other hand, influences on the formation of a porous structure in the extrudates.

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Biological control of Listeria monocytogenes in soil model systems by Enterococcus mundtii strains expressing mundticin KS production

Applied Soil Ecology ◽

10.1016/j.apsoil.2021.104293 ◽

2022 ◽

Vol 170 ◽

pp. 104293

Author(s):

Gaetano Guida ◽

Raimondo Gaglio ◽

Alessandro Miceli ◽

Vito Armando Laudicina ◽

Luca Settanni

Keyword(s):

Biological Control ◽

Listeria Monocytogenes ◽

Model Systems ◽

Soil Model ◽

Enterococcus Mundtii

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Structural analysis of lignin-derived carbon composite anodes

Journal of Applied Crystallography ◽

10.1107/s1600576714014666 ◽

2014 ◽

Vol 47 (5) ◽

pp. 1577-1584 ◽

Cited By ~ 6

Author(s):

Nicholas W. McNutt ◽

Orlando Rios ◽

Mikhail Feygenson ◽

Thomas E. Proffen ◽

David J. Keffer

Keyword(s):

Volume Fraction ◽

Carbon Composite ◽

Distribution Functions ◽

Model Systems ◽

Dynamics Simulation ◽

Nanocrystalline And Amorphous ◽

Composite Anodes ◽

Relationship Of ◽

The Relationship ◽

Pair Distribution Functions

The development of novel lignin-based carbon composite anodes consisting of nanocrystalline and amorphous domains motivates the understanding of the relationship of the structural properties characterizing these materials, such as crystallite size, intracrystallitedspacing, crystalline volume fraction and composite density, with their pair distribution functions (PDFs), obtained from both molecular dynamics simulation and neutron scattering. A model for these composite materials is developed as a function of experimentally measurable parameters and realized in 15 composite systems, three of which directly match all parameters of their experimental counterparts. The accurate reproduction of the experimental PDFs using the model systems validates the model. The decomposition of the simulated PDFs provides an understanding of each feature in the PDF and allows for the development of a mapping between the defining characteristics of the PDF and the material properties of interest.

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