Analysis of surface waves generated on subwavelength-structured silver films

Using transmission electron microscopy (TEM) to analyse the physical-chemical surface properties of subwavlength structured silver films and finite-difference time-domain (FDTD) numerical simulations of the optical response of these structures to plane-wave excitation, we report on the origin and nature of the persistent surface waves generated by a single slit-groove motif and recently measured by far-field optical interferometry. The surface analysis shows that the silver films are free of detectable oxide or sulfide contaminants, and the numerical simulations show very good agreement with the results previously reported.Comment: 9 Figure

Об истории открытия и природе алмазов в вулканических породах Камчатки

The history of the discovery of diamonds in the products of Kamchatka volcanic eruptions is briefly described, and the results of comprehensive studies of Tolbachin diamonds including crystallomorphology, faceted sculptures, xenomineral greases and films on the surface, nanomicroswitches, impurity elements, spectroscopic properties, isotopic composition of carbon and nitrogen are summarized. The conclusion is drawn about the natural origin of the Tolbachin diamonds formed directly in the volcanic ash-gas cloud by crystallization from gases stimulated by atmospheric electric discharges.Кратко описана история открытия алмазов в продуктах извержений вулканов Камчатки и обобщены результаты комплексных исследований толбачинских алмазов – кристалломорфологии, гранной скульптуры, ксеноминеральных примазок и пленок на поверхности, наномикровключений, элементов-примесей, спектроскопических свойств, изотопного состава углерода и азота. Сделан вывод о природном происхождении толбачинских алмазов, образовавшихся непосредственно в среде вулканического пеплогазового облака путем кристаллизации из газов, стимулированной атмосферными электрическими разрядами

Precise measurement of RudsR_{\text{uds}} and RR between 1.84 and 3.72 GeV at the KEDR detector

The present work continues a series of the KEDR measurements of the $R$ value that started in 2010 at the VEPP-4M $e^+e^-$ collider. By combining new data with our previous results in this energy range we measured the values of $R_{\text{uds}}$ and $R$ at nine center-of-mass energies between 3.08 and 3.72 GeV. The total accuracy is about or better than $2.6\%$ at most of energy points with a systematic uncertainty of about $1.9\%$. Together with the previous precise $R$ measurement at KEDR in the energy range 1.84-3.05 GeV, it constitutes the most detailed high-precision $R$ measurement near the charmonium production threshold.Comment: arXiv admin note: text overlap with arXiv:1610.02827 and substantial text overlap with arXiv:1510.0266

Vibrational Spectra of a Mechanosensitive Channel

We report the simulated vibrational spectra of a mechanosensitive membrane channel in different gating states. Our results show that while linear absorption is insensitive to structural differences, linear dichroism and sum-frequency generation spectroscopies are sensitive to the orientation of the transmembrane helices, which is changing during the opening process. Linear dichroism cannot distinguish an intermediate structure from the closed structure, but sum-frequency generation can. In addition, we find that two-dimensional infrared spectroscopy can be used to distinguish all three investigated gating states of the mechanosensitive membrane channel.

Иммунохимическое исследование бронхиального секрета в оценке степени эндобронхита

We detected albumin (A), lactoferrin (LF), ferritin (F), C-reactive protein (CRP), fibrinogen degradation products (FDP), serum α-, β- and g-globulins, non-specific tissue esterase (NTE), total and placental alkaline phosphatase (TAP and PAP) dynamically in the bronchial secretion (sputum and bronchial aspirates) of 268 patients with bronchopulmonary pathology (pneumonia, chronic non-specific lung diseases, lung abscess, tuberculosis, lung tumours, pleural empyema) using immunochemical methods with rabbit anti-sera and corresponding reagents.A strong correlations between a width of the antigen spectrum and endoscopic, clinical-and-radiological, cytological or bacteriological evidences of endobronchitis seventy were found. The appearance of NTE and PAF thermoresistent forms demonstrates a high risk for malignance development or tumor occurrence.С помощью кроличьих антисывороток и соответствующих реактивов иммунохимическими методами в бронхиальном секрете (мокрота, бронхоаспираты) определяли альбумин (А), лактоферрин (ЛФ), ферритин (Ф), С-реактивный протеин (С-РП), продукты деградации фибриногена (ПДФ), сывороточные α-, β-, g-глобулины, неспецифическую тканевую эстеразу (НТЭ), суммарную и плацентарную щелочную фосфатазу (СЩФ и ПЩФ) у 268 больных с бронхолегочной патологией (пневмония, хронические неспецифические заболевания легких, абсцесс, туберкулез, опухоли легких, эмпиема плевры) в динамике заболевания.Обнаружена высокая корреляция между насыщенностью антигенного спектра бронхиального секрета и эндоскопическим, клинико-рентгенологическим, цитологическим и бактериоскопическим подтверждением степени выраженности эндобронхита. Появление термостабильных изоформ НТЭ и ПЩФ отражает высокий риск или наличие малигнизации

MscS-like mechanosensitive channels in plants and microbes

The challenge of osmotic stress is something all living organisms must face as a result of environmental dynamics. Over the past three decades, innovative research and cooperation across disciplines have irrefutably established that cells utilize mechanically gated ion channels to release osmolytes and prevent cell lysis during hypoosmotic stress. Early electrophysiological analysis of the inner membrane of Escherichia coli identified the presence of three distinct mechanosensitive activities. The subsequent discoveries of the genes responsible for two of these activities, the mechanosensitive channels of large (MscL) and small (MscS) conductance, led to the identification of two diverse families of mechanosensitive channels. The latter of these two families, the MscS family, consists of members from bacteria, archaea, fungi, and plants. Genetic and electrophysiological analysis of these family members has provided insight into how organisms use mechanosensitive channels for osmotic regulation in response to changing environmental and developmental circumstances. Furthermore, determining the crystal structure of E. coli MscS and several homologues in several conformational states has contributed to our understanding of the gating mechanisms of these channels. Here we summarize our current knowledge of MscS homologues from all three domains of life and address their structure, proposed physiological functions, electrophysiological behaviors, and topological diversity

Molecular and Electrophysiological Characterization of a Novel Cation Channel of Trypanosoma cruzi

We report the identification, functional expression, purification, reconstitution and electrophysiological characterization of a novel cation channel (TcCat) from Trypanosoma cruzi, the etiologic agent of Chagas disease. This channel is potassium permeable and shows inward rectification in the presence of magnesium. Western blot analyses with specific antibodies indicated that the protein is expressed in the three main life cycle stages of the parasite. Surprisingly, the parasites have the unprecedented ability to rapidly change the localization of the channel when they are exposed to different environmental stresses. TcCat rapidly translocates to the tip of the flagellum when trypomastigotes are submitted to acidic pH, to the plasma membrane when epimastigotes are submitted to hyperosmotic stress, and to the cell surface when amastigotes are released to the extracellular medium. Pharmacological block of TcCat activity also resulted in alterations in the trypomastigotes ability to respond to hyperosmotic stress. We also demonstrate the feasibility of purifying and reconstituting a functional ion channel from T. cruzi after recombinant expression in bacteria. The peculiar characteristics of TcCat could be important for the development of specific inhibitors with therapeutic potential against trypanosomes