725 research outputs found
Langmuir monolayers and thin films of amphifilic thiacalix[4]arenes. properties and matrix for the immobilization of cytochrome c
© 2014 American Chemical Society. Formation and properties of Langmuir films of thiacalix[4]arene (TCA) derivatives containing N-donor groups on the lower rim (Y=O(CH2)3CN; OCH2CN; NH2; OCH2ArCN-p) in 1,3-alternate conformation on aqueous subphase and solid substrates have been studied. Only tetra-cyanopropoxy-p-tert-butylthiacalix[4]arene 1 forms a typical monomolecular layer with perpendicular orientation of the macrocycle relative to the water-air interface that is able to immobilize cytochrome c in the entire range of the surface pressure. Obtained monolayers were transferred by Langmuir-Schaefer technique onto quartz, indium-tin oxide (ITO), and silicon. It was demonstrated that protein activity is retained after immobilization on the substrate
Screening studies of POP levels in fish from selected lakes in the Paz watercourse
Appendix 8/15 of the publication "State of the environment in the Norwegian, Finnish and Russian border area 2007" (The Finnish Environment 6/2007)
Thiacalix[4]monocrowns substituted by sulfur-containing anchoring groups: New ligands for gold surface modification
Crown containing calix[4]arenes 2a-f with thioacetate-functionalized carbon chains on lower rim in 1,3-alternate conformation were synthesized starting from corresponding bromo-derivatives. The use of thiacalixcrowns monolayer films improves adhesion between gold and biomolecules (cytochrome c and catalase). The structures of these monolayers were analyzed using contact angle measurements and AFM visualization by discontinuous contact mode. © ISUCT Publishing
Mapping of T7 RNA polymerase active site with novel reagents – oligonucleotides with reactive dialdehyde groups
AbstractOligonucleotides of a novel type containing 2′-O-β-ribofuranosyl-cytidine were synthesized and further oxidized to yield T7 consensus promoters with dialdehyde groups. Both types of oligonucleotides were tested as templates, inhibitors, and affinity reagents for T7 RNA polymerase and its mutants. All oligonucleotides tested retained high affinity towards the enzyme. Wild-type T7 RNA polymerase and most of the mutants did not react irreversibly with oxidized oligonucleotides. Affinity labeling was observed only with the promoter-containing dialdehyde group in position (+2) of the coding chain and one of the mutants tested, namely Y639K. These results allowed us to propose the close proximity of residue 639 and the initiation region of the promoter within initiation complex. We suggest the oligonucleotides so modified may be of general value for the study of protein-nucleic acid interactions
Catalog of dessins d'enfants with \le 4 edges
In this work all the dessins d'enfant with no more than 4 edges are listed
and their Belyi pairs are computed. In order to enumerate all dessins the
technique of matrix model computations was used. The total number of dessins is
134; among them 77 are spherical, 53 of genus 1 and 4 of genus 2. The orders of
automorphism groups of all the dessins are also found.
Dessins are listed by the number of edges. Dessins with the same number of
edges are ordered lexicographically by their lists of 0-valencies. The
corresponding matrix model for any list of 0-valencies is given and computed.
Complex matrix models for dessins with 1 -- 3 edges are used. For the dessins
with 4 edges we use Hermitian matrix model, correlators for which are computed
in [1].Comment: 64 pages, 134 figure
Эффективность газомоторного топлива для сельхозтехники
Expediency and efficiency of use of natural gas motor fuel (GMF) for mobile agricultural machinery is defined on the basis of alternative calculations of commercial effectiveness of use of the compressed natural gas (CNG), liquefied natural gas (LNG) and the liquefied petroleum gas (LPG) in large agricultural enterprise «Kazminskoye» in the Stavropol Territory where costs of fuel for machines and tractors make 222.5 million rubles a year. Need of field gas refueling of tractors and combines as a specifics fuel utilization by mobile agricultural machinery was considered at calculations. For an assessment of a type of GMF and influence of cost of a refueling complex on commercial effectiveness the authors have carried out comparative calculations of technical and economic efficiency of utilization of CNG, LNG and LPG, taking into account and without a refueling complex. High efficiency of GMF utilization was showed: fuel costs decrease by 1.7 times, the payback period of capital investments equals to 0.4-4.2 years. The best results were obtained when utilization LPG. Total costs of re-equipment and a refueling complex in option with LPG are 3.5 times as less as with CNG, and 6 times as less as with LNG. The payback period of capital investments for re-equipment without refueling complex equals to 0.4; 0.8 and 2.4 years respectively for LPG, CNG and LNG. Taking into account refueling means it increases to 0.9; 2.4 and 4.2 years. In 10 years the net present value taking into account refueling means equals to 276.7 million; 289.9 million and 206.8 million rubles for LPG, CNG and LNG respectively due to fleet re-equipment.В настоящее время в связи с растущим диспаритетом цен на топливо и сельхозпродукцию весьма актуальной задачей для сельхозтехники является поиск более дешевого альтернативного моторного топлива. Наиболее реальной альтернативой нефтяным моторным топливам выступает газомоторное топливо (ГМТ). Целесообразность и эффективность использования газомоторного топлива для мобильной сельхозтехники определили на основе вариантных расчетов коммерческой эффективности применения компримированного природного газа (КПГ), сжиженного природного газа (СПГ) и сжиженного углеводородного газа (СУГ) в крупном сельхозпредприятии «Казьминское», площадью пашни более 30 тыс. га, его автотракторный парк включает 365 ед., в том числе 279 тракторов, из них 32 мощных трактора «Кировец», затраты на топливо по автотракторной технике составляют 222,5 млн руб. в год. При расчетах учитывали специфику применения моторного топлива для мобильной сельхозтехники, для которой необходима полевая заправка тракторов и комбайнов. Для оценки вида ГМТ и влияния стоимости заправочного комплекса на коммерческую эффективность выполнили сравнительные расчеты технико-экономической эффективности применения КПГ, СПГ и СУГ с учетом и без учета заправочного комплекса. Исходные данные расчетов определяли по результатам приемочных испытаний сельхозтехники на машинно-испытательных станциях. Расчеты по технико-экономическому обоснованию целесообразности использования ГМТ потвердели высокую экономическую эффективность их применения. Показали высокую эффективность применения ГМТ: затраты на топливо снижаются в 1,7 раза, срок окупаемости капитальных вложений: 0,4-4,2 года. Лучшие результаты получены при использовании СУГ, суммарные затраты на переоборудование и заправочный комплекс в варианте с СУГ в 3,5 раза меньше, чем с КПГ, и в 6 раз меньше чем с СПГ. Срок окупаемости капиталовложений на переоборудование техники без заправочного комплекса составляет 0,4; 0,8 и 2,4 года соответственно для СУГ, КПГ и СПГ, с учетом заправочных средств он возрастает до 0,9; 2,4 и 4,2 лет. Чистый дисконтированный доход за 10 лет от переоборудования парка с учетом заправочных средств составляет для СУГ, КПГ и СПГ соответственно 276,7 млн; 289,9 млн; 206,8 млн рублей
Statin-Induced Myopathy
Scientific relevance. Being the main class of medicinal products for dyslipidaemia treatment, statins are widely used in clinical practice in various patient populations. However, statins can cause statin-associated muscle symptoms (SAMS), which are the most frequent and, in some cases, even life-threatening adverse reactions associated with these medicinal products.Aim. The study aimed to perform a systematic review of the epidemiology, classification, and physiological pathogenesis of SAMS, risk factors for this complication, and clinical guidelines for primary care physicians regarding the identification and treatment of patients with SAMS.Discussion. SAMS is an umbrella term that covers various forms of myopathies associated with satin therapy. According to the published literature, the prevalence of SAMS varies considerably and may depend on the study design, inclusion criteria, and the medicinal product used. SAMS has multiple putative pathogenic pathways that include genetically determined processes, abnormalities in mitochondrial function, defects in intracellular signalling and metabolic pathways, and immune-mediated reactions. The main known risk factors for developing SAMS include high-dose statins, drug–drug interactions, genetic polymorphisms, female sex, older age, Asian race, history of kidney, liver, and muscle disease, and strenuous physical activity. Given the lack of universally recognised algorithms for diagnosing SAMS, clinicians should consider the clinical presentation and the temporal relationship between statin therapy and symptoms. Other factors to consider include changes in muscle-specific enzyme levels and, in some cases, the results of blood tests for antibodies to 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase.Conclusions. To ensure the safety of statin therapy, it is essential to raise clinicians’ awareness of the risk factors for SAMS, indicative clinical and laboratory findings, and the need for dynamic patient monitoring, including the involvement of clinical pharmacologists
Measurement of the mid-rapidity transverse energy distribution from GeV Au+Au collisions at RHIC
The first measurement of energy produced transverse to the beam direction at
RHIC is presented. The mid-rapidity transverse energy density per participating
nucleon rises steadily with the number of participants, closely paralleling the
rise in charged-particle density, such that E_T / N_ch remains relatively
constant as a function of centrality. The energy density calculated via
Bjorken's prescription for the 2% most central Au+Au collisions at
sqrt(s_NN)=130 GeV is at least epsilon_Bj = 4.6 GeV/fm^3 which is a factor of
1.6 larger than found at sqrt(s_NN)=17.2 GeV (Pb+Pb at CERN).Comment: 307 authors, 6 pages, 4 figures, 1 table, submitted to PRL 4/18/2001;
revised version submitted to PRL 5/24/200
Centrality Dependence of Charged Particle Multiplicity in Au-Au Collisions at sqrt(s_NN)=130 GeV
We present results for the charged-particle multiplicity distribution at
mid-rapidity in Au - Au collisions at sqrt(s_NN)=130 GeV measured with the
PHENIX detector at RHIC. For the 5% most central collisions we find
. The results,
analyzed as a function of centrality, show a steady rise of the particle
density per participating nucleon with centrality.Comment: 307 authors, 43 institutions, 6 pages, 4 figures, 1 table Minor
changes to figure labels and text to meet PRL requirements. One author added:
M. Hibino of Waseda Universit
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