Search results for " function"
showing 10 items of 9395 documents
Similarity and Specificity of Chlorophyll b Triplet State in Comparison to Chlorophyll a as Revealed by EPR/ENDOR and DFT Calculations
2019
An investigation of the photoexcited triplet state of chlorophyll (Chl) b has been carried out by means of electron nuclear double resonance, both in a frozen organic solvent and in a protein environment provided by the water-soluble chlorophyll protein of Lepidium virginicum. Density functional theory calculations have allowed the complete assignment of the observed hyperfine couplings corresponding to the methine protons and the methyl groups, leading to a complete picture of the spin density distribution of the triplet state in the tetrapyrrole macrocycle. The triplet-state properties of Chl b are found to be similar, in many respects, to those previously reported for Chl a, although som…
Automatic detection of large dense-core vesicles in secretory cells and statistical analysis of their intracellular distribution.
2010
Analyzing the morphological appearance and the spatial distribution of large dense-core vesicles (granules) in the cell cytoplasm is central to the understanding of regulated exocytosis. This paper is concerned with the automatic detection of granules and the statistical analysis of their spatial locations in different cell groups. We model the locations of granules of a given cell as a realization of a finite spatial point process and the point patterns associated with the cell groups as replicated point patterns of different spatial point processes. First, an algorithm to segment the granules using electron microscopy images is proposed. Second, the relative locations of the granules with…
Gibbs' Dividing Surface between a Fixed-Charge Membrane and an Electrolyte Solution. Application to Electrokinetic Phenomena in Charged Pores
1999
The Gibbs model for the boundary between two phases consists of replacing the finite interfacial region, where the properties of the system change gradually, by a dividing surface which acts as a third phase of zero volume in which some magnitudes change abruptly. This thermodynamic concept was recently applied to a planar interface between a fixed charge membrane and an electrolyte solution.1 The continuous decrease of counterions with the distance from the charged surface is replaced by a step function, so that the diffuse double layer is ideally represented by a charged region depleted of all co-ions. Here the cylindrical geometry is analyzed, and the planar case is revisited by proposin…
Peak deconvolution in one-dimensional chromatography using a two-way data approach.
2002
A deconvolution methodology for overlapped chromatographic signals is proposed. Several single-wavelength chromatograms of binary mixtures, obtained in different runs at diverse concentration ratios of the individual components, were simultaneously processed (multi-batch approach), after being arranged as two-way data. The chromatograms were modelled as linear combinations of forced peak profiles according to a polynomially modified Gaussian equation. The fitting was performed with a previously reported hybrid genetic algorithm with local search, leaving all model parameters free. The approach yielded more accurate solutions than those found when each experimental chromatogram was fitted in…
Statistical Approach for Biomarker Discovery Using Label-Free LC-MS Data: An Overview
2016
The identification of new diagnostic, prognostic, or theranostics biomarkers is one of the main aims of clinical research. Technologies like mass spectrometry (MS) focus on the discovery of proteins as biomarkers and are commonly being used for this purpose. Mass spectrometry consists in the separation by gas of charged molecules, based on their mass-over-charge. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) first involves a separation by liquid chromatography (LC) followed by mass spectrometry in the MS and MS/MS modes.
Strong circularly polarized luminescence of an octahedral chromium(iii) complex
2019
The chiral spin-flip luminophore [Cr(ddpd)2]3+ can be resolved into enantiopure material by chiral HPLC. The corresponding enantiomers show very high luminescence dissymmetry factors of up to ∣glum ∣≈ 0.093 in circularly polarized luminescence (CPL) measurements for the "ruby-like" phosphorescence transition 2E/2T1 → 4A2 in the near-IR region around λ ≈ 775 nm.
Relationship status and respiratory diseases: an analysis on a general population sample
2021
Background: Very few studies have examined whether marital/relationship status affects respiratory diseases. Objective: Assess the association of relationship status (Rstatus: domestic partnership/civil union/marriage, cohabitation with non-partners, being single) with current (CA) and past asthma (PA), allergic (AR) and non-allergic rhinitis (NAR), and chronic bronchitis (CB). Methods: Data were collected in the frame of GEIRD, a population-based, multicase-control survey. Among 2531 subjects (age 21–86, female 50%) who underwent standardized interviews, skin prick and lung function tests, 575 cases of CA, 268 cases of PA, 968 cases of AR, 462 cases of NAR, 265 cases of CB without airflow …
Effects of sleep apnea and kidney dysfunction on objective sleep quality in nondialyzed patients with chronic kidney disease: an ESADA study
2020
Study Objectives: Patients with chronic kidney disease (CKD) often report poor sleep quality, but they commonly exhibit OSA. The aim of this study was to evaluate the influence of OSA severity and of estimated glomerular filtration rate impairment on objective sleep quality in nondialyzed patients with CKD, defined as an estimated glomerular filtration rate <60 mL/min/1.73m2. Methods: Polysomnographic sleep characteristics were compared between patients with (n = 430) and without CKD (n = 6,639) in the European Sleep Apnea Database cohort. Comparisons were repeated in 375 patients with CKD and 375 control patients without CKD matched for sleep center, age, sex, and AHI, and in 310 matche…
Strenuous endurance exercise and right ventricular systolic function: no evidence of long-term sequelae.
2014
a Faculty of Medicine, Department of Physiology, University of Valencia, Valencia, Spain b Fundacion de Investigacion del Hospital Clinico Universitario Valencia (FIHCUV-INCLIVA), Valencia, Spain c Faculty of Health and Sport Science, University of Zaragoza, Huesca, Spain d Hospital Universitario 12 de Octubre, Research Institute (i + 12), Madrid, Spain e HospitalUniversitario Miguel Servet, Zaragoza, Spain f Cardiology Service, Hospital Universitario Miguel Servet, Zaragoza, Spain g European University of Madrid, Madrid, Spain h Faculty of Medicine, Physical Education and Sports Section, University of Zaragoza, Zaragoza, Spain
Contact-induced phenomena in the Alps
2019
The main question underlying this chapter is to what extent language contact can affect syntactic structure. To tackle this issue we examine two relevant phenomena found in two minority languages spoken in the region Trentino-Alto Adige/South Tyrol: clitic climbing in Dolomitic Ladin and the use of the Romance complementizer ke in Cimbrian. Both phenomena are usually considered as the result of a contact-induced change influenced by the neighbouring Italo-Romance varieties. However, it is shown that the rising of clitic climbing is a language-internal process which is only accelerated by the contact with Italian. Similarly, the lexical borrowing of the complementizer ke in Cimbrian does not…