159 research outputs found
Effect of urea and tmao on lipid bilayers
Abstract
We study the effect of the osmolytes, Urea and trimethylamine-N-oxide (TMAO) on POPE (1-palmitoyl-2-oleoyl-sn-glycero-3- phosphoethanolamine) lipid membranes using SAXS/WAXS and DSC. Their antagonist effect is observed with TMAO stabilizing and Urea destabilizing the lipid bilayer, as seen by others in earlier researches
Self-Ordered Voids Formation in SiO2 Matrix by Ge Outdiffusion
The annealing behavior of very thin SiO2/Ge multilayers deposited on Si substrate by e-gun deposition in high vacuum was explored. It is shown that, after annealing at moderate temperatures (800°C) in inert atmosphere, Ge is completely outdiffused from the SiO2 matrix leaving small (about 3ânm) spherical voids embedded in the SiO2 matrix. These voids are very well correlated and formed at distances governed by the preexisting multilayer structure (in vertical direction) and self-organization (in horizontal direction). The formed films produce intensive photoluminescence (PL) with a peak at 500ânm. The explored dynamics of the PL decay show the existence of a very rapid process similar to the one found at Ge/SiO2 defected interface layers
Effect of Blend Composition and Additives on the Morphology of PCPDTBT:PC71BM Thin Films for Organic Photovoltaics.
The use of solvent additives in the fabrication of bulk heterojunction polymer:fullerene solar cells allows to boost efficiencies in several low bandgap polymeric systems. It is known that solvent additives tune the nanometer scale morphology of the bulk heterojunction. The full mechanism of efficiency improvement is, however, not completely understood. In this work, we investigate the influences of blend composition and the addition of 3 vol % 1,8-octanedithiol (ODT) as solvent additive on polymer crystallization and both, vertical and lateral morphologies of poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] and [6,6]-phenyl C71-butyric acid methyl ester (PCPDTBT:PC71BM) blend thin films processed from chlorobenzene-based solutions. The nanoscale morphology is probed with grazing incidence small- and wide-angle X-ray scattering as well as X-ray reflectivity and complemented with UV/vis spectroscopy. In PCPDTBT:PC71BM films the use of ODT is found to lower the solubility of fullerene in the polymer matrix and to promote polymer crystallization, both vertical and lateral microphase separation with morphological coarsening, and formation of a fullerene-rich topping layer. The enhanced photovoltaic performance is explained by these findings
A closer look into two-step perovskite conversion with X-ray scattering
Recently, hybrid perovskites have gathered much interest as alternative materials for the fabrication of highly efficient and cost-competitive solar cells; however, many questions regarding perovskite crystal formation and deposition methods remain. Here we have applied a two-step protocol where a crystalline PbI2 precursor film is converted to MAPbI3âxClx perovskite upon immersion in a mixed solution of methylammonium iodide and methylammonium chloride. We have investigated both films with grazing incidence small-angle X-ray scattering to probe the inner film morphology. Our results demonstrate a strong link between lateral crystal sizes in the films before and after conversion, which we attribute to laterally confined crystal growth. Additionally, we observe an accumulation of smaller grains within the bulk in contrast with the surface. Thus, our results help to elucidate the crystallization process of perovskite films deposited via a two-step technique that is crucial for controlled film formation, improved reproducibility, and high photovoltaic performance
Influence of annealing conditions on formation of regular lattices of voids and Ge quantum dots in amorphous alumina matrix
In this work, the influence of air pressure during the annealing of Ge quantum dot (QD) lattices embedded in an amorphous Al2O3 matrix on the structural, morphological and compositional properties of the film is studied. The formation of a regularly ordered void lattice after performing a thermal annealing process is explored. Our results show that both the
Ge desorption from the film and the regular ordering of the QDs are very sensitive to the
annealing parameters. The conditions for the formation of a void lattice, a crystalline Ge QD lattice and a disordered QD lattice are presented. The observed effects are explained in terms of oxygen interaction with the Ge present in the film.This study has been partially funded through the projects (i) FEDER funds through the COMPETE program âPrograma
Operacional Factores de Competitividadeâ and by Portuguese funds through the Portuguese foundation for Science
and Technology (FCT) in the frame of the project PTDC/FIS/70194/2006 and PEst-C-FIS/UI607/2011â2012;
(ii) ELETTRA Synchrotron Radiation Center through the European Communityâs Seventh Framework Programme
(FP7/2007â2013) under grant agreement no 226716. SRCP
is grateful for financial support through the FCT grant
SFRH/BPD/73548/2010 and JMS is grateful for financial
support through the Spanish CSIC JAE-DOC program.
MB acknowledges support from the Croatian Ministry
of Science, Higher Education and Sport (project number
098-0982886-2859).We thank Dr Anabela Rolo and Engineer
JosÂŽe Santos for all the valuable discussions and the sample
preparation
A Syngeneic Orthotopic Murine Model of Pancreatic Adenocarcinoma in the C57/BL6 Mouse Using the Panc02 and 6606PDA Cell Lines
Background/Aims: To develop a clinically relevant immunocompetent murine model to study pancreatic cancer using two different syngeneic pancreatic cancer cell lines and to assess MRI for its applicability in this model. Methods: Two cell lines, 6606PDA and Panc02, were employed for the experiments. Cell proliferation and migration were monitored in vitro. Matrigelâą was tested for its role in tumor induction. Tumor cell growth was assessed after orthotopic injection of tumor cells into the pancreatic head of C57/BL6 mice by MRI and histology. Results: Proliferation and migration of Panc02 were significantly faster than those of 6606PDA. Matrigel did not affect tumor growth/migration but prevented tumor cell spread after injection thus avoiding undesired peritoneal tumor growth. MRI could reliably monitor longitudinal tumor growth in both cell lines: Panc02 had a more irregular finger-like growth, and 6606PDA grew more spherically. Both tumors showed local invasiveness. Histologically, Panc02 showed a sarcoma-like undifferentiated growth pattern, whereas 6606PDA displayed a moderately differentiated glandular tumor growth. Panc02 mice had a significantly shorter (28 days) survival than 6606PDA mice (50 days). Conclusion: This model closely mimics human pancreatic cancer. MRI was invaluable for longitudinal monitoring of tumor growth thus reducing the number of mice required. Employing two different cell lines, this model can be used for various treatment and imaging studies
Unklare chronische Schwindelsyndrome â Erfahrungen mit einem interdisziplinĂ€ren stationĂ€ren Diagnostikkonzept
Dizziness is a common leading symptom. Especially patients with chronic vertigo syndromes experience a significant impairment in quality of life up to a limitation of their ability to work in the case of employed persons. The consequences are financial and capacitive burdens on the health system due to frequently multiple examinations and sick leave up to occupational invalidity of the affected patient. In 150 patients with chronic vertigo syndromes and an unclear outpatient diagnosis, at least one diagnosis that justified the complaint was made in over 90% of cases on the basis of a structured interdisciplinary inpatient diagnostic concept. Chronic vertigo syndromes are often multifactorial. Psychosomatic (accompanying) diagnoses were found in more than half of the patients. Targeted therapy can only be recommended after establishing a specific diagnosis. This justifies an interdisciplinary inpatient diagnostic concept for persistently unclear cases
Production of three-dimensional quantum dot lattice of Ge/Si coreâshell quantum dots and Si/Ge layers in an alumina glass matrix
Balancing, Proportionality, and Constitutional Rights
In the theory and practice of constitutional adjudication, proportionality review plays a crucial role. At a theoretical level, it lies at core of the debate on rights adjudication; in judicial practice, it is a widespread decision-making model characterizing the action of constitutional, supra-national and international courts. Despite its circulation and centrality in contemporary legal discourse, proportionality in rights-adjudication is still extremely controversial. It raises normative questionsâconcerning its justification and limitsâand descriptive questionsâregarding its nature and distinctive features. The chapter addresses both orders of questions.
Part I centres on the justification of proportionality review, the connection between proportionality, balancing and theories of rights and the critical aspects of this connection.
Part II identifies and analyses the different forms of proportionality both in review, as a template for rights-adjudication, and of review, as a way of defining the scope and limits of adjudication
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