scholarly journals Information capacity of specific interactions

2016 ◽  
Vol 113 (21) ◽  
pp. 5841-5846 ◽  
Author(s):  
Miriam H. Huntley ◽  
Arvind Murugan ◽  
Michael P. Brenner
Keyword(s):  
Self Assembly ◽  
Physical Parameters ◽  
Specific Interactions ◽  
Color Coding ◽  
Chemical Mechanisms ◽  
Experimental Systems ◽  
Shape Coding ◽  
Target Binding ◽  
Strongly Sublinear ◽  
Physical And Chemical

Specific interactions are a hallmark feature of self-assembly and signal-processing systems in both synthetic and biological settings. Specificity between components may arise from a wide variety of physical and chemical mechanisms in diverse contexts, from DNA hybridization to shape-sensitive depletion interactions. Despite this diversity, all systems that rely on interaction specificity operate under the constraint that increasing the number of distinct components inevitably increases off-target binding. Here we introduce “capacity,” the maximal information encodable using specific interactions, to compare specificity across diverse experimental systems and to compute how specificity changes with physical parameters. Using this framework, we find that “shape” coding of interactions has higher capacity than chemical (“color”) coding because the strength of off-target binding is strongly sublinear in binding-site size for shapes while being linear for colors. We also find that different specificity mechanisms, such as shape and color, can be combined in a synergistic manner, giving a capacity greater than the sum of the parts.

scholarly journals Synthesis and Self-Assembly of Gold Nanoparticles by Chemically Modified Polyol Methods under Experimental Control

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Nguyen Viet Long ◽  
Michitaka Ohtaki ◽  
Masayoshi Yuasa ◽  
Satoshi Yoshida ◽  
Taiga Kuragaki ◽  
...  
Keyword(s):  
Self Assembly ◽  
Au Nanoparticles ◽  
Collective Oscillation ◽  
Synthesis Time ◽  
Chemical Mechanisms ◽  
Chemically Modified ◽  
Valence Electrons ◽  
Surface Electrons ◽  
General Physical ◽  
Physical And Chemical

In our present research, bottom-up self-assembly of gold (Au) nanoparticles on a flat copper (Cu) substrate is performed by a facile method. The very interesting evidence of self-assembly of Au nanoparticles on the top of the thin assembled layer was observed by scanning electron microscopy (SEM). We had discovered one of the most general and simple methods for the self-assembly of metal nanoparticles. The general physical and chemical mechanisms of the evaporation process of the solvents can be used for self-assembly of the as-prepared nanoparticles. The important roles of molecules of the used solvents are very critical to self-assembly of the as-prepared Au nanoparticles in the case without using any polymers for those processes. It is clear that self-assembly of such one nanosystem of the uniform Au nanoparticles is fully examined. Finally, an exciting surface plasmon resonance (SPR) phenomenon of the pure Au nanoparticles in the solvent was fully discovered in their exciting changes of the narrow and large SPR bands according to synthesis time. The SPR was considered as the collective oscillation of valence electrons of the surfaces of the pure Au nanoparticles in the solvent by incident ultraviolet-visible light. Then, the frequency of light photons matches the frequency of the oscillation of surface electrons of the Au nanoparticles that are excited.

scholarly journals Changes in Optical Properties upon Dye–Clay Interaction: Experimental Evaluation and Applications

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 197
Author(s):  
Giorgia Giovannini ◽  
René M. Rossi ◽  
Luciano F. Boesel
Keyword(s):  
Optical Properties ◽  
Hybrid Materials ◽  
High Performance ◽  
Fluorescent Properties ◽  
Chemical Mechanisms ◽  
Strong Electrostatic Interaction ◽  
Potential Applications ◽  
Photochemical Properties ◽  
Physical And Chemical ◽  
The Relationship

The development of hybrid materials with unique optical properties has been a challenge for the creation of high-performance composites. The improved photophysical and photochemical properties observed when fluorophores interact with clay minerals, as well as the accessibility and easy handling of such natural materials, make these nanocomposites attractive for designing novel optical hybrid materials. Here, we present a method of promoting this interaction by conjugating dyes with chitosan. The fluorescent properties of conjugated dye–montmorillonite (MMT) hybrids were similar to those of free dye–MMT hybrids. Moreover, we analyzed the relationship between the changes in optical properties of the dye interacting with clay and its structure and defined the physical and chemical mechanisms that take place upon dye–MMT interactions leading to the optical changes. Conjugation to chitosan additionally ensures stable adsorption on clay nanoplatelets due to the strong electrostatic interaction between chitosan and clay. This work thus provides a method to facilitate the design of solid-state hybrid nanomaterials relevant for potential applications in bioimaging, sensing and optical purposes.

The Varied Causes of Color in Glass

1985 ◽  
Vol 61 ◽  
Author(s):  
K. Nassau
Keyword(s):  
Chalcogenide Glasses ◽  
Water Ligand ◽  
Ligand Field ◽  
Energy Bands ◽  
Metal Compounds ◽  
Chemical Mechanisms ◽  
Doped Glasses ◽  
Blue Eyes ◽  
Physical And Chemical ◽  
Ice Water

ABSTRACTAll but two of the fifteen physical and chemical mechanisms which are necessary to explain all the varied causes of color apply in one way or another to glass. These fifteen causes of color derive from a variety of physical and chemical mechanisms and are summarized in five groups with concentration on those mechanisms that apply to glass and the related glazes and enamels. Vibrations and simple excitations explain the colors of incandescence (e.g. flames, hot glass), gas excitations (neon tube, aurora), and vibrations and rotations (blue ice, water, glasses based on water). Ligand field effect colors are seen in transition metal compounds (turquoise, chrome oxide green, glasses based on copper sulfate) and impurities (ruby, emerald, many doped glasses). Molecular orbitals explain the colors of organic compounds (indigo, chlorophyll, organic glasses) and charge transfer compounds (blue sapphire, lapis lazuli, “beer-bottle” brown and chromate glasses). Energy bands are involved in the colors of metals and alloys (gold, brass, glassy metals), of semiconductors (cadmium yellow, vermillion, chalcogenide glasses), doped semiconductors (blue and yellow diamond), and color centers (amethyst, topaz, irradiated glass). Geometrical and physical optics are involved in the colors derived from dispersive refraction (rainbow, green flash, glass prism spectrum), scattering (blue sky, blue eyes, red sunset, ruby gold and opal glasses), interference (soap bubbles, iridescent beetles, cracks in glasses, interference filters), and diffraction (the corona aureole, diffraction grating spectrum).

scholarly journals Polymeric Drug Delivery System Based on Pluronics for Cancer Treatment

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3610
Author(s):  
Jialin Yu ◽  
Huayu Qiu ◽  
Shouchun Yin ◽  
Hebin Wang ◽  
Yang Li
Keyword(s):  
Drug Delivery ◽  
Self Assembly ◽  
Drug Delivery Systems ◽  
Tumor Therapy ◽  
Chemical Properties ◽  
Drug Carriers ◽  
Disease Diagnosis ◽  
Delivery Systems ◽  
Polymeric Drug Delivery ◽  
Physical And Chemical

Pluronic polymers (pluronics) are a unique class of synthetic triblock copolymers containing hydrophobic polypropylene oxide (PPO) and hydrophilic polyethylene oxide (PEO) arranged in the PEO-PPO-PEO manner. Due to their excellent biocompatibility and amphiphilic properties, pluronics are an ideal and promising biological material, which is widely used in drug delivery, disease diagnosis, and treatment, among other applications. Through self-assembly or in combination with other materials, pluronics can form nano carriers with different morphologies, representing a kind of multifunctional pharmaceutical excipients. In recent years, the utilization of pluronic-based multi-functional drug carriers in tumor treatment has become widespread, and various responsive drug carriers are designed according to the characteristics of the tumor microenvironment, resulting in major progress in tumor therapy. This review introduces the specific role of pluronic-based polymer drug delivery systems in tumor therapy, focusing on their physical and chemical properties as well as the design aspects of pluronic polymers. Finally, using newer literature reports, this review provides insights into the future potential and challenges posed by different pluronic-based polymer drug delivery systems in tumor therapy.

scholarly journals Predicting carbon nanotube forest attributes and mechanical properties using simulated images and deep learning

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Taher Hajilounezhad ◽  
Rina Bao ◽  
Kannappan Palaniappan ◽  
Filiz Bunyak ◽  
Prasad Calyam ◽  
...  
Keyword(s):  
Machine Learning ◽  
Deep Learning ◽  
Carbon Nanotube ◽  
High Throughput ◽  
Self Assembly ◽  
Mechanical Performance ◽  
Physical Parameters ◽  
Structure Property ◽  
Processing Parameter ◽  
Physics Based Simulation

AbstractUnderstanding and controlling the self-assembly of vertically oriented carbon nanotube (CNT) forests is essential for realizing their potential in myriad applications. The governing process–structure–property mechanisms are poorly understood, and the processing parameter space is far too vast to exhaustively explore experimentally. We overcome these limitations by using a physics-based simulation as a high-throughput virtual laboratory and image-based machine learning to relate CNT forest synthesis attributes to their mechanical performance. Using CNTNet, our image-based deep learning classifier module trained with synthetic imagery, combinations of CNT diameter, density, and population growth rate classes were labeled with an accuracy of >91%. The CNTNet regression module predicted CNT forest stiffness and buckling load properties with a lower root-mean-square error than that of a regression predictor based on CNT physical parameters. These results demonstrate that image-based machine learning trained using only simulated imagery can distinguish subtle CNT forest morphological features to predict physical material properties with high accuracy. CNTNet paves the way to incorporate scanning electron microscope imagery for high-throughput material discovery.

scholarly journals Microfluidics-based Bioassays and Imaging of Plant Cells

2021 ◽  
Author(s):  
Naoki Yanagisawa ◽  
Elena Kozgunova ◽  
Guido Grossmann ◽  
Anja Geitmann ◽  
Tetsuya Higashiyama
Keyword(s):  
High Resolution ◽  
Agar Plate ◽  
Root Hairs ◽  
Plant Cells ◽  
Individual Plant ◽  
Experimental Systems ◽  
Surrounding Matrix ◽  
Sense And Respond ◽  
Physical And Chemical ◽  
Microfabrication Techniques

Abstract Many plant processes occur in the context of and in interaction with a surrounding matrix such as soil (e.g. root growth and root–microbe interactions) or surrounding tissues (e.g. pollen tube growth through the pistil), making it difficult to study them with high-resolution optical microscopy. Over the past decade, microfabrication techniques have been developed to produce experimental systems that allow researchers to examine cell behavior in microstructured environments that mimic geometrical, physical and/or chemical aspects of the natural growth matrices and that cannot be generated using traditional agar plate assays. These microfabricated environments offer considerable design flexibility as well as the transparency required for high-resolution, light-based microscopy. In addition, microfluidic platforms have been used for various types of bioassays, including cellular force assays, chemoattraction assays, and electrotropism assays. Here, we review the recent use of microfluidic devices to study plant cells and organs, including plant roots, root hairs, moss protonemata, and pollen tubes. The increasing adoption of microfabrication techniques by the plant science community may transform our approaches to investigating how individual plant cells sense and respond to changes in the physical and chemical environment.

scholarly journals Kajian kualitas air pada area budidaya kurungan jaring tancap (KJT) di Danau Tutud Desa Tombatu Tiga Kecamatan Tombatu Kabupaten Minahasa Tenggara

2017 ◽  
Vol 5 (1) ◽  
Author(s):  
Christian Tokah ◽  
Suzanne L. Undap ◽  
Sammy N.J. Longdong
Keyword(s):  
Water Quality ◽  
Good Condition ◽  
Laboratory Analysis ◽  
Ex Situ ◽  
Primary Data ◽  
Physical Parameters ◽  
Chemical Parameters ◽  
Research Activities ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical

The aim of this study was to measure and assess the physical and chemical parameters of water quality in the area of ​​fixnet cage cultureat Lake Tutud Tombatu TigaVillagewhich included temperature, pH, DO, TDS, NO3, NO2, NH3 and PO4 in a different time.This research was conducted from August to November 2016. The research activities consisted of direct measurements in the field (in situ) using a Horiba instrument and laboratory analysis (ex situ) at the Agency for Industrial Research and Development Research Institute of Standardization and Industrial Manado. Determination points were done by purposive sampling which refers to the physiographic location wherever possible in order to represent or describe these waters.Water quality measured at4 stations using a Horiba at a depth of 0.5 meters from the bottom of the lake.Station I represented Inlet water, Station II where the cultivation A, Station III where the cultivation B and Station IVwhere no cultivation. The data obtained and collected were primary data i.e., measurement of physical and chemical parameters of water quality as well as watching for signs of sick fish, dead fish, and the growth of farmed fish.The results showed the water temperature ranged between 28-29 ° C, TDS 0266-0412 mg/L and chemical parameters for dissolved oxygen 2-5 mg/L, pH 7-8 and for the results of laboratory analysis, N03(0.7 - 6.3 mg/L), NO2(0001-0002 mg/L), NH3 (0180-1920 mg/L), PO4(0020-0209 mg/L). In general, the existence of water quality of lake Tutud were still in good condition except for NH3 concentrationthat exceeded quality standard limitsof Government Regulation No. 82 of 2001. Basically lake Tutud can still be used for fish farming, but the addition of new cages were not recommended.   Keywords: Lake Tutud,water quality, physical parameters, chemical parameters, fix net cage

scholarly journals A COMPARATIVE STUDY OF ANTIMICROBIAL PROFILE HAVING BROAD SPECTRUM BACTERIOCINS AGAINST ANTIBIOTICS

2017 ◽  
Vol 10 (9) ◽  
pp. 44 ◽  
Author(s):  
Sabiha Imran ◽  
Twinkle Gupta ◽  
Aarti Arora ◽  
Nilanjan Das
Keyword(s):  
Broad Spectrum ◽  
Cationic Peptides ◽  
Promising Alternative ◽  
Bacterial Diseases ◽  
Adverse Side Effects ◽  
Experimental Systems ◽  
Improper Use ◽  
Physical And Chemical

  Bacteriocins are ribosomally synthesized antimicrobial peptides produced by microbes owned by different eubacterial taxonomic branches. Most of them are small cationic membrane-active compounds that form pores in the targeted cells, disrupting membrane possibilities, and triggering cell fatality. The availability of small cationic peptides with antimicrobial activity is a protection strategy found not only in bacteria but also in plants and animals. The antibiotics which have extensive applications in the treatment of various bacterial diseases have developed alarming resistance against them in many pathogens due to improper use besides this antibiotics have adverse side effects also. There are an extensive variety of bacteriocins made by different bacterial genera have promising alternative to antibiotics that needs to be further studied to show the no existence of undesirable effects, which must be performed both in vitro and in vivo experimental systems. Most of the bacteriocin have narrow spectrum of their activity and effective only on the related species. There is an urgent need for the identification of broad-spectrum bacteriocins isolated from the species from different habitats that can be effective against both Gram-positive and Gram-negative pathogens. In this review, we focus on the main physical and chemical characteristics of broad-spectrum bacteriocin and discuss their application as an alternative option to antibiotics.

scholarly journals Expanding the molecular-ruler process through vapor deposition of hexadecanethiol

2017 ◽  
Vol 8 ◽  
pp. 2339-2344 ◽  
Author(s):  
Alexandra M Patron ◽  
Timothy S Hooker ◽  
Daniel F Santavicca ◽  
Corey P Causey ◽  
Thomas J Mullen
Keyword(s):  
Vapor Phase ◽  
Self Assembly ◽  
Chemical Properties ◽  
Solution Deposition ◽  
Precise Control ◽  
Vapor Phase Deposition ◽  
Great Utility ◽  
Complex Architectures ◽  
Molecular Ruler ◽  
Physical And Chemical

The development of methods to produce nanoscale features with tailored chemical functionalities is fundamental for applications such as nanoelectronics and sensor fabrication. The molecular-ruler process shows great utility for this purpose as it combines top-down lithography for the creation of complex architectures over large areas in conjunction with molecular self-assembly, which enables precise control over the physical and chemical properties of small local features. The molecular-ruler process, which most commonly uses mercaptoalkanoic acids and metal ions to generate metal-ligated multilayers, can be employed to produce registered nanogaps between metal features. Expansion of this methodology to include molecules with other chemical functionalities could greatly expand the overall versatility, and thus the utility, of this process. Herein, we explore the use of alkanethiol molecules as the terminating layer of metal-ligated multilayers. During this study, it was discovered that the solution deposition of alkanethiol molecules resulted in low overall surface coverage with features that varied in height. Because features with varied heights are not conducive to the production of uniform nanogaps via the molecular-ruler process, the vapor-phase deposition of alkanethiol molecules was explored. Unlike the solution-phase deposition, alkanethiol islands produced by vapor-phase deposition exhibited markedly higher surface coverages of uniform heights. To illustrate the applicability of this method, metal-ligated multilayers, both with and without an alkanethiol capping layer, were utilized to create nanogaps between Au features using the molecular-ruler process.

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