A novel approach for systematically calibrating transport planning model systems

2018 ◽  
Vol 46 (5) ◽  
pp. 1915-1950 ◽  
Author(s):  
Ali Najmi ◽  
Taha H. Rashidi ◽  
Eric J. Miller
Keyword(s):  
Model Systems ◽  
Planning Model ◽  
Transport Planning ◽  
Novel Approach

Tailoring Polymer Surfaces for Controlled Cell Behavior

1998 ◽  
Vol 530 ◽  
Author(s):  
A.M. Mayes ◽  
D.J. Irvine ◽  
L.G. Griffith
Keyword(s):  
Protein Adsorption ◽  
Surface Segregation ◽  
Cell Attachment ◽  
Model Systems ◽  
Protein Resistance ◽  
Small Proteins ◽  
Novel Approach ◽  
Poly Ethylene ◽  
Comb Copolymer ◽  
Adhesion Ligand

AbstractAn ideal surface for many biomaterials applications would resist nonspecific protein adsorption while at the same time providing a means for specifically signaling cells to guide survival, growth, migration, and differentiation. This work was directed towards the investigation of model systems and clinically-applicable materials which provide both of these surface requirements. Model systems were prepared by chemically grafting end-functionalized star poly(ethylene oxide) (PEO) to surfaces. The end-grafted polymers provide a means for cell-signaling through coupling of peptides to the free chain ends. Protein adsorption on star vs. linear grafted layers was compared. To further understand these results, neutron reflectivity studies were carried out in situ for solvated PEO surfaces to determine the concentration profiles of the swollen grafted layers. Surprisingly, grafted PEO layers which resist protein adsorption have low concentrations of polymer segments throughout the swollen layer. We find that dense star architectures which might be expected to impart improved protein resistance in fact allow small proteins to adsorb. For clinical materials, a novel approach to the surface modification of poly(lactide) (PLA) has been taken by surface segregating a comb copolymer containing a PLA backbone and poly(ethylene glycol) teeth. The ends of the teeth provide sites for surface tethering of peptide ligands. Comb surfaces without tethered ligands are cell adhesion resistant, indicating strong protein adsorption resistance. By then incorporating an adhesion ligand, modulation of cell morphology on comb surfaces has been demonstrated. Finally, the surface segregation of the comb to the surface of PLA was shown via cell attachment assays and XPS measurements.

Study of Container Transport Planning Model and Algorithm

2012 ◽  
Vol 11 (1) ◽  
pp. 306-309 ◽  
Author(s):  
Xin Zhang ◽  
Qingnian Zhang ◽  
Jingsong Lin ◽  
Zhiqiang Zhao
Keyword(s):  
Planning Model ◽  
Transport Planning ◽  
Container Transport

A Novel Approach Based on Two-Dimensional Correlation Spectroscopy to Determine the Stoichiometric Ratio of Two Substances Involved in Intermolecular Interactions

2019 ◽  
Vol 73 (9) ◽  
pp. 1051-1060 ◽  
Author(s):  
Xiaopei Li ◽  
Yiwei Zeng ◽  
Gang Deng ◽  
Yizhuang Xu ◽  
Yukihiro Ozaki ◽  
...  
Keyword(s):  
Intermolecular Interactions ◽  
Ethylenediaminetetraacetic Acid ◽  
Disodium Salt ◽  
Correlation Spectroscopy ◽  
Model Systems ◽  
Stoichiometric Ratio ◽  
Chemical Systems ◽  
Supramolecular Aggregate ◽  
Novel Approach ◽  
Job's Method

A novel technique called AOSD@Job’s, combining asynchronous orthogonal sample design scheme (AOSD) with Job’s method, is proposed to estimate the stoichiometric ratio of two substances that form a supramolecular aggregate under intermolecular interactions. First, a mathematical analysis was performed along with the procedure of the AOSD@Job’s method. Then, the validity of the AOSD@Job’s method was manifested by computer simulation on two model systems. Finally, the AOSD@Job’s method was applied on two real chemical systems. The stoichiometric ratio between the coordination complex of Ni2+ and ethylenediaminetetraacetic acid disodium salt (EDTA) was estimated to be 1.0. Benzyl alcohol (BA) and β-cyclodextrin (β-CD) were determined to form a 1 : 1 host–guest complex. These values were consistent with the values reported in the literature. Compared with the traditional Job’s method, the AOSD@Job’s method has an evident advantage since it is still valid even if all the peaks of the supramolecular aggregate severely overlap with the peaks of the substances that form the aggregate.

scholarly journals Structure of DPPC Monolayers at the Air/Buffer Interface: A Neutron Reflectometry and Ellipsometry Study

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 507
Author(s):  
Javier Carrascosa-Tejedor ◽  
Andreas Santamaria ◽  
Daniel Pereira ◽  
Armando Maestro
Keyword(s):  
Structural Information ◽  
Langmuir Monolayers ◽  
Neutron Reflectometry ◽  
Model Systems ◽  
Angle Of Incidence ◽  
Water Interface ◽  
Brewster Angle Microscopy ◽  
Degree Of Hydration ◽  
Novel Approach ◽  
Air Water Interface

Langmuir monolayers of 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine, known as DPPC, at the air/water interface are extensively used as model systems of biomembranes and pulmonary surfactant. The properties of these monolayers have been mainly investigated by surface pressure–area isotherms coupled with different complementary techniques such as Brewster angle microscopy, for example. Several attempts using neutron reflectometry (NR) or ellipsometry have also appeared in the literature. Here, we report structural information obtained by using NR and ellipsometry on DPPC monolayers in the liquid condensed phase. On one side, NR can resolve the thickness of the aliphatic tails and the degree of hydration of the polar headgroups. On the other side, ellipsometry gives information on the refractive index and, therefore, on the physical state of the monolayer. The thickness and surface excess obtained by multiple-angle-of-incidence ellipsometry (MAIE) is compared with the results from NR measurements yielding a good agreement. Besides, a novel approach is reported to calculate the optical anisotropy of the DPPC monolayer that depends on the orientation of the aliphatic chains. The results from both NR and ellipsometry are also discussed in the context of the existing results for DPPC monolayers at the air/water interface. The differences observed are rationalized by the presence of buffer molecules interacting with phospholipids.

scholarly journals ROUTE RECOVERY ALGORITHM USING GEOINFORMATION DATA

2021 ◽  
Vol 1 (1) ◽  
pp. 179-180
Author(s):  
Ol'ga Lebedeva ◽  
Zuy Ta
Keyword(s):  
Visual Presentation ◽  
Transport Network ◽  
Planning Model ◽  
Geoinformation System ◽  
Transport Planning ◽  
Maximum Information ◽  
Recovery Algorithm ◽  
Modeling Practices ◽  
Few Data ◽  
Route Recovery

Techniques for optimizing the transport network using an array of data obtained from sensors of the geoinformation system (GIS) are constantly being tested in practice in different countries. For freight transport, few data are available. The development of a transport planning model makes it possible to obtain maximum information from each dataset. Considering the modern realities of the development of methods, a visual presentation of the results of modeling with the support of GIS is required, with non-standard modeling practices

scholarly journals Induction of different human enteroendocrine cells in intestinal organoids

2020 ◽  
Author(s):  
Hans Clevers ◽  
Joep Beumer
Keyword(s):  
Cell Types ◽  
Bmp Signaling ◽  
Enteroendocrine Cells ◽  
Model Systems ◽  
Endocrine Organ ◽  
Intestinal Organoids ◽  
Novel Approach ◽  
Key Players ◽  
And Function ◽  
Diabetes And Obesity

Abstract Intestinal enteroendocrine cells \(EECs) are key players in mammalian physiology as largest endocrine organ, and regulate metabolic processes such as insulin secretion and induction of satiety. EECs are rare cell types \(less than 1% of the epithelium) and produce a large number of different hormones making these challenging to study. Model systems to assess the differentiation and function of these essential cell types have been lacking. In a novel approach, we describe the induction of human EECs in intestinal organoids. Moreover, in the manuscript linked to this protocol, we describe that manipulating the BMP signaling pathway allows to induce expression of specific sets of hormones that correspond to the EEC state in the crypt-villus axis. This differentiation platform can be used to study the function of EECs and could contribute to the development of drugs for diabetes and obesity.

The Anomaly of Bacterial Genetics

2021 ◽  
pp. 37-43
Author(s):  
Thomas E. Schindler
Keyword(s):  
Molecular Biology ◽  
Model Systems ◽  
Darwinian Evolution ◽  
Bacterial Conjugation ◽  
Bacterial Genetics ◽  
New Model ◽  
Novel Approach ◽  
Foundational Research ◽  
Gregor Mendel ◽  
Classical Genetics

This chapter reviews the research that set the stage for Joshua Lederberg’s surprising discovery of bacterial conjugation. While the foundational research of Gregor Mendel and his principles of inheritance had been effectively combined with Darwinian evolution, producing the Modern Synthesis in the mid-forties, bacteria did not fit into this grand synthesis. Most biologists believed that bacteria were too primitive to have real genes. But Delbruck, Hershey and Luria organized the Phage School, leading a novel approach to discovering the molecular biology of the gene by studying bacteriophages. Microbiologists like Tracy Sonneborn and Carl Lindegren turned to alternative microorganisms—protists, fungi, and yeast—to develop new model systems that offered advantages over the classical genetics organisms of animals and plants. The research of Edward Tatum and Jacques Monod indicated that mutations seemed to explain variation in bacteria. For many years, however, bacteriologists had known that bacteria reproduced by fission. The lack of any genetic hybridization seemed to argue against using bacteria to study basic genetic processes.

Sign in / Sign up

Export Citation Format

Share Document