By using in-situ neutron reflectivity, we have investigated swelling isotherms of solvophilic and solvophobic end-grafted/non-grafted polymer chains on solid substrates in supercritical carbon ...dioxide and supercritical ethane. It was found that anomalous expansion of the polymer chains associated with excess absorption of the fluid molecules occurs in the large compressible regions of both supercritical fluids (SCFs) regardless of the polymer–fluid interactions. In addition, we found that the excess expansion of the solvophobic polymer chains in both SCFs collapse onto one master curve under the same magnitude of density fluctuations in the fluids. A simple thermodynamic two-state model along with the experimental results proposes that polymer chains are expanded independently of the polymer–fluid interactions to further change solvent density fluctuations around the polymer chains, thereby lowering the free energy of the polymer/SCF systems.
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The aim of this study was to identify the sequence mutations in the
(
) gene that has been considered as one of the strong candidate genes. A total of 30 children and adolescents (aged 3-18) with non ...syndromic autism were enrolled this study. Sequencing of the coding exons and the exon-intron boundaries of the
gene was performed. Two known mutations were described in two different cases. Heterozygous S14L was determined in one patient and heterozygous L748I was determined in another patient. The S14L and L748I mutations have been described in the patients with autism before. Both of these mutations were inherited from their father. In this study, two of 30 (6.7%) autism spectrum disorder (ASD) patients carrying
gene mutations were detected. It indicates that variants in the
gene might confer a risk of developing nonsyndromic ASD. However, due to the reduced penetrance in the gene, the causal role of the
gene mutations must be evaluated carefully in all cases.
Purpose
The aim of this study is to evaluate the association between lesion progression and the ischemic or edematous area that can develop around the hemorrhage in intraparenchymal hemorrhagic ...lesions originating after head trauma.
Methods
Thirty patients with intracerebral hemorrhage due to head trauma of a mild or intermediate degree were evaluated in this study. Brain diffusion MRI examinations were performed in the first 6 h after trauma in all patients. In addition, a computerized cranial tomography (CCT) was performed upon admission (in the first hour), and at 24 and 48 h after admission. Patients with or without progression of the lesion were compared.
Results
The increase in the risk of progression of the lesion in patients with an ischemia/hemorrhage rate > 2 identified in the diffusion MRIs by evaluation of the hemorrhagic and the surrounding ischemic area, obtained in the first 6 h after trauma was found to be statistically significant. The possibility of progression was found to be very low when this rate was less than two.
Conclusions
As a result of the study, the ischemic area was found to be proportionally larger in patients with progression compared to nonprogressing patients with traumatic intracerebral hemorrhage. The ischemia/hemorrhage rate in the diffusion MRI is thought to be an important parameter, beneficial to identify the risk of lesion progression.
We report a mobility gradient of polymer chains in close proximity of a planar solid substrate in compressed carbon dioxide (CO2) gas. A series of bilayers composed of bottom hydrogenated polystyrene ...(h-PS) and top deuterated PS (d-PS) layers were prepared on Si substrates. A high-pressure neutron reflectivity (NR) technique was used to study the diffusive motion at the h-PS/d-PS interface as a function of the distance from the substrate interface. The results reveal that the interdiffusive chain dynamics gets strongly hindered compared to the bulk when the distance from the substrate is less than 3R g (R g is the radius of polymer gyration of the h-PS). At the same time, by utilizing rapid quench of CO2 and subsequent solvent leaching, we reveal the presence of the CO2-induced polymer adsorbed layer on the substrate. We postulate that loop components in the adsorbed polymer chains provide a structure that can trap the neighboring polymer chains effectively, hence reducing the chain mobility in the close vicinity of the solid substrate even in the presence of the effective plasticizer.
Purpose The aim of this study is to evaluate the association between lesion progression and the ischemic or edematous area that can develop around the hemorrhage in intraparenchymal hemorrhagic ...lesions originating after head trauma. Methods Thirty patients with intracerebral hemorrhage due to head trauma of a mild or intermediate degree were evaluated in this study. Brain diffusion MRI examinations were performed in the first 6 h after trauma in all patients. In addition, a computerized cranial tomography (CCT) was performed upon admission (in the first hour), and at 24 and 48 h after admission. Patients with or without progression of the lesion were compared. Results The increase in the risk of progression of the lesion in patients with an ischemia/hemorrhage rate > 2 identified in the diffusion MRIs by evaluation of the hemorrhagic and the surrounding ischemic area, obtained in the first 6 h after trauma was found to be statistically significant. The possibility of progression was found to be very low when this rate was less than two. Conclusions As a result of the study, the ischemic area was found to be proportionally larger in patients with progression compared to nonprogressing patients with traumatic intracerebral hemorrhage. The ischemia/hemorrhage rate in the diffusion MRI is thought to be an important parameter, beneficial to identify the risk of lesion progression.
The author describes his development of a computer-based paper-marbling tool, based on a traditional Turkish art form in which marbled-paper figures and patterns are created on the surface of a ...liquid bath. Similar works can be obtained by simulating fluid flows on a computer, using the Navier-Stokes equations as the physical model of the fluid flows. The author has created an application program that includes marbling tools. Such a program must run in real time, so that hand-eye coordination is required of the user. Real-time simulation of fluid flows requires much processor power. The author has attempted to adapt this technique for use with a personal computer. To decrease the processing power required, the image size may be decreased, but the results may not be as satisfactory.
Morphology control in bulk heterojunction (BHJ) solar cell is considered to be critical for the power conversion efficiency (PCE). In this paper, we present a novel approach that introduces ...polystyrene that organizes the poly(3-hexylthiophene) (P3HT) into columnar phases decorated by 6,6-phenyl C61-butyric acid methyl ester (PCBM) at the interface. This structure represents a realization of an idealized morphology of an organic solar cell, in which both exiciton dissociation and the carrier transport are optimized, leading to increased power conversion efficiency.
“Grafting from” surface-initiated atom transfer radical polymerization (ATRP) techniques were used to synthesize semifluorinated diblock copolymer brushes from silica substrates. Synthesis of either ...a polystyrene or poly(methyl acrylate) homopolymer brush was performed first (inner block) followed by polymerization of a semifluorinated monomer (outer block). The semifluorinated outer block consisted either of poly(pentafluorostyrene), poly(heptadecafluorodecyl acrylate), poly(pentafluoropropyl acrylate), or poly(trifluoroethyl acrylate). Analysis of the homopolymer and diblock copolymer brush layers was conducted using ellipsometry, ATR−FTIR, tensiometry, XPS, and AFM. Solvent-induced diblock rearrangement experiments were performed using a selective solvent for the hydrocarbon polymer block to generate a fluorine-deficient surface. With the exception of the systems containing PHFA, all the diblock systems were shown to exhibit water contact angles typical for the hydrocarbon polymer block after solvent treatment. Poor rearrangement for diblock copolymer brushes containing PHFA was observed when compared to all other semifluorinated diblock copolymer systems. The extent of diblock rearrangement was correlated to the calculated values for the solubility parameters of each block.
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