Coil-globule transition in aqueous solutions of quaternized poly(4-vinylpyridine) derivatives and sodium dodecyl sulfate

Aqueous solutions of cationic polyelectrolytes (quaternized derivatives of poly(vinylpyridine)) and an anionic surfactant (sodium dodecyl sulfate) were studied by potentiometric titration using surfactant-selective and bromide-selective electrodes, as well as by the methods of microelectrophoresis, viscometry, spectrophotometry, dye solubilization, and pH control. The experimental evidence obtained revealed a new phenomenon: at a certain concentration of surfactant in polymer solutions, once the macromolecular ion has been saturated with surfactant molecules, a noticeable fraction of surfactant ions is expelled from the polyelectrolyte complex, and the vacant sites are occupied by inorganic counterions. This structural transition was discussed within the framework of the theory of coil-globule conformational transition. Schematic representation of pretransition and posttransition states of the polyelectrolyte-surfactant associates was advanced

HEREDITARY INTRAVENTRICULAR CONDUCTION DISORDERS IN THE FAMILY FROM KRASNOYARSK

Pedigree of the family from Krasnoyarsk city with hereditary disorders of intracardiac conduction was studied. The diagnosis of each family member was verified by electrocardiography (ECG), echocardiography , bicycle ergometry , ECG Holter monitoring. The family 10-year follow-up showed familial aggregation of intracardiac conduction disorders in grandson, niece, son of the proband niece, ie, in the III-degree relatives. Family history of III-degree relatives with intracardiac conduction disorders and discordant pathology is identified

Microscopic description of cluster radioactivity in actinide nuclei

Cluster radioactivity is the emission of a fragment heavier than an α particle and lighter than mass 50. The range of clusters observed in experiments goes from 14C to 32Si while the heavy mass residue is always a nucleus in the neighborhood of the doubly-magic 208Pb nucleus. Cluster radioactivity is described in this paper as very asymmetric nuclear fission. A new fission valley leading to a decay with large fragment mass asymmetry matching the cluster radioactivity products is found. The mass octupole moment is found to be more convenient than the standard quadrupole moment as the parameter driving the system to fission. The mean-field Hartree-Fock-Bogoliubov theory with the phenomenological Gogny interaction has been used to compute the cluster emission properties of a wide range of even-even actinide nuclei from 222Ra to 242Cm, where emission of the clusters has been experimentally observed. Computed half-lives for cluster emission are compared with experimental results. The noticeable agreement obtained between the predicted properties of cluster emission (namely, cluster masses and emission half-lives) and the measured data confirms the validity of the proposed methodology in the analysis of the phenomenon of cluster radioactivity. A continuous fission path through the scission point has been described using the neck parameter constraintThe work of LMR was supported by Ministerio de Ciencia e Innovacion (Spain) Grants No. FPA2009-08958 and No. FIS2009-07277, as well as by Consolider-Ingenio 2010 Programs CPAN CSD2007-00042 and MULTIDARK CSD2009- 00064. The work of MW was supported by Ministerstwo Nauki i Szkolnictwa Wyzszego (Poland) under Grant No. N N202 23113

Легочный амилоидоз

Amyloidosis is an orphan disease. Amyloidosis is uncommonly associated with respiratory disorders. The present article is a review of recently published data on pulmonary amyloidosis and a case report of alveolar and septal amyloid lung injury. Clinical heterogeneity of lung lesions in systemic and limited AL amyloidosis (precursor proteins are light chains of immunoglobulins, λ dimer and κ monomer), AA amyloidosis (inflammatory acute-phase proteins), and ATTR amyloidosis (senile and inherited amyloidosis; precursor protein is transthyretin) have been discussed. One chart of the review has been devoted to the pathogenesis of diffuse parenchymatous (unilateral and bilateral) amyloidosis, nodular and tracheobronchial amyloidosis (with amyloid deposits in proximal, medium and distal airways, intrathoracic lymph node involvement (amyloid lymphadenopathy), amyloidosis of the pleura and the diaphragm, and differential diagnosis of these types of pulmonary amyloidosis.Амилоидоз относится к классу орфанных заболеваний. Среди других систем организма с амилоидозом в наименьшей степени ассоциирована дыхательная система. Современные данные по проблеме легочного амилоидоза представлены на основе литературного обзора и авторского описания редкого примера альвеолярно-септальной формы поражения легких; рассмотрены вопросы клинической неоднородности пульмонологической патологии при системном и местном амилоидозе (AL – белок-предшественник – легкие цепи иммуноглобулинов, димер λ и мономер κ; АА – воспалительные острофазовые белки; ATTR – старческий и наследственный, белок-предшественник транстиретин). Один из разделов посвящен патогенезу диффузного паренхиматозного (одностороннего и двустороннего), узлового и трахеобронхиального (с депозитами амилоида в проксимальных, средних или дистальных отделах бронхиального дерева) вариантов болезни, вовлечению в процесс внутригрудных лимфатических узлов (амилоидная аденопатия), плевры и диафрагмы, вопросам дифференциальной диагностики данных вариантов легочного амилоидоза

Floristic analysis of a high-speed railway embankment in a Mediterranean landscape

We analyzed the floristic composition of a 4.5 km-long segment of a high-speed railway in Lazio, central Italy, which travels on an artificial embankment through an intensively-farmed landscape. In total, 287 vascular plant species were recorded. The life-form distribution was found to be similar to that of the regional species pool, with high percentages of therophytes (38%) and phanerophytes (13%). In the chorological spectrum the Mediterranean floristic element prevailed (44%), while alien species were 8% of the flora. The phytosociological spectrum showed a high diversity of characteristic species from the class Stellarietea mediae or its subordinate syntaxa (26%), and in particular from the order Thero-Brometalia (Mediterranean, sub-nitrophilous annual communities). Species from forest syntaxa had a relatively high diversity (9%). These results suggest that the ecological filtering provided by the Mediterranean regional climate controlled species assemblage even in a completely artificial habitat, preventing floristic homogenization: the flora of the studied railway section is only partially »ruderalized«, while it keeps strong links with the regional (semi-) natural plant communities. However, in contrast to what is observed in central and north Europe, the railway sides studied in the present paper do not seem to represent a refugial habitat for rare species from grassland communities, mainly because in Italy semi-natural dry grasslands are still widely represented

Coil-globule transition in aqueous solutions of quaternized poly(4-vinylpyridine) derivatives and sodium dodecyl sulfate

Aqueous solutions of cationic polyelectrolytes (quaternized derivatives of poly(vinylpyridine)) and an anionic surfactant (sodium dodecyl sulfate) were studied by potentiometric titration using surfactant-selective and bromide-selective electrodes, as well as by the methods of microelectrophoresis, viscometry, spectrophotometry, dye solubilization, and pH control. The experimental evidence obtained revealed a new phenomenon: at a certain concentration of surfactant in polymer solutions, once the macromolecular ion has been saturated with surfactant molecules, a noticeable fraction of surfactant ions is expelled from the polyelectrolyte complex, and the vacant sites are occupied by inorganic counterions. This structural transition was discussed within the framework of the theory of coil-globule conformational transition. Schematic representation of pretransition and posttransition states of the polyelectrolyte-surfactant associates was advanced

Coil-globule transition in aqueous solutions of quaternized poly(4-vinylpyridine) derivatives and sodium dodecyl sulfate

Aqueous solutions of cationic polyelectrolytes (quaternized derivatives of poly(vinylpyridine)) and an anionic surfactant (sodium dodecyl sulfate) were studied by potentiometric titration using surfactant-selective and bromide-selective electrodes, as well as by the methods of microelectrophoresis, viscometry, spectrophotometry, dye solubilization, and pH control. The experimental evidence obtained revealed a new phenomenon: at a certain concentration of surfactant in polymer solutions, once the macromolecular ion has been saturated with surfactant molecules, a noticeable fraction of surfactant ions is expelled from the polyelectrolyte complex, and the vacant sites are occupied by inorganic counterions. This structural transition was discussed within the framework of the theory of coil-globule conformational transition. Schematic representation of pretransition and posttransition states of the polyelectrolyte-surfactant associates was advanced

Coil-globule transition in aqueous solutions of quaternized poly(4-vinylpyridine) derivatives and sodium dodecyl sulfate

Aqueous solutions of cationic polyelectrolytes (quaternized derivatives of poly(vinylpyridine)) and an anionic surfactant (sodium dodecyl sulfate) were studied by potentiometric titration using surfactant-selective and bromide-selective electrodes, as well as by the methods of microelectrophoresis, viscometry, spectrophotometry, dye solubilization, and pH control. The experimental evidence obtained revealed a new phenomenon: at a certain concentration of surfactant in polymer solutions, once the macromolecular ion has been saturated with surfactant molecules, a noticeable fraction of surfactant ions is expelled from the polyelectrolyte complex, and the vacant sites are occupied by inorganic counterions. This structural transition was discussed within the framework of the theory of coil-globule conformational transition. Schematic representation of pretransition and posttransition states of the polyelectrolyte-surfactant associates was advanced

GENETIC PREDICTORS OF IDIOPATHIC SICK SINUS SYNDROME

Dans le cadre d’une recherche documentaire, les travaux des « jeunes chercheurs », ou plutôt des jeunes recherches, sont trop souvent mis de côté. On assiste à alors à la citation récurrente des mêmes travaux, sans prendre en compte l’évolution rapide de la recherche sur le Rwanda. De nombreuses thèses ont ainsi été soutenues ces dernières années en France ou à l’étranger. On peut citer par exemple en France la thèse de Benoit Guillou ((GUILLOU Benoît, Le pardon à l’épreuve d’un génocide. Di..

GENETIC PREDICTORS OF IDIOPATHIC SICK SINUS SYNDROME

Published data demonstrating genetic determination of sick sinus syndrome is presented. The definition of this pathology is presented; the main symptoms are described, as well as genes that influence the development of idiopathic sick sinus syndrome, their polymorphisms and role in disorders of the cardiovascular system.</p