Triiodothyronine Represses MUC5AC Expression by Antagonizing Sp1 Binding to Its Promoter in Human Bronchial Epithelial HBE16 Cells

Mucus hypersecretion is a distinguished feature of chronic inflammatory airway diseases. Interestingly, in this condition thyroid function is impaired with decreased level of triiodothyronine (T3), indicating potential link between low level of T3 and mucus hypersecretion. But the underlying mechanisms are poorly understood. In this study we aimed to elucidate the effect of T3 on MUC5AC secretion in human bronchial epithelial HBE16 cells and further investigate how T3 regulates MUC5AC gene expression at transcriptional level. By RT-PCR and ELISA we showed that T3 inhibited MUC5AC mRNA expression and protein secretion in HBE16 cells. Furthermore, luciferase assay and site-directed mutagenesis analysis demonstrated that T3 repressed MUC5AC expression at transcriptional level and the mechanism might partly lie in the specific inhibition of Sp1 binding to the promoter. Our results suggest that decreased T3 level leads to the release of repression of MUC5AC expression and thus contributes to mucus hypersecretion

Azimuthal modulation of the event rate of cosmic ray extensive air showers by the geomagnetic field

The Earth's magnetic field effect on the azimuthal distribution of extensive air showers (EAS) of cosmic rays has been evaluated using a bulk of the Yakutsk array data. The uniform azimuthal distribution of the EAS event rate is rejected at the significance level 10^(-14). Amplitude of the first harmonics of observed distribution depends on zenith angle as A1=0.2*sin^2(theta) and is almost independent of the primary energy; the phase coincides with the magnetic meridian. Basing upon the value of measured effect, the correction factor has been derived for the particle density depending on a geomagnetic parameter of a shower.Comment: 4 pages, 3 figures in ps file

Fluctuations of development maximum depth and nuclear composition of primary cosmic radiation

The extensive air showers (EAS) cascade curves from the Cerenkov light lateral distribution measurements are recovered and the maximum depth fluctuations of the shower development theta x sub m both on the Cerenkov and charged EAS components are defined. At E sub 0 approximates 10 to the 18th power eV the mean content of protons is greater than 85%, and p-air cross section theta sub 0 p-air 750mb

Quantum Information Processing with Ferroelectrically Coupled Quantum Dots

I describe a proposal to construct a quantum information processor using ferroelectrically coupled Ge/Si quantum dots. The spin of single electrons form the fundamental qubits. Small (<10 nm diameter) Ge quantum dots are optically excited to create spin polarized electrons in Si. The static polarization of an epitaxial ferroelectric thin film confines electrons laterally in the semiconductor; spin interactions between nearest neighbor electrons are mediated by the nonlinear process of optical rectification. Single qubit operations are achieved through "g-factor engineering" in the Ge/Si structures; spin-spin interactions occur through Heisenberg exchange, controlled by ferroelectric gates. A method for reading out the final state, while required for quantum computing, is not described; electronic approaches involving single electron transistors may prove fruitful in satisfying this requirement.Comment: 10 pages, 3 figure

Проблемы разжижения грунтов в основаниях гидротехнических сооружений

An analysis of the probability and conditions for the occurrence of soil liquefaction at the base and in the vicinity of hydraulic structures is presented in the paper. As a rule, hydraulic structures are erected in the valleys of watercourses, the structure of the soil in which contributes to the occurrence of liquefaction processes. These soils are fine-grained, non-cohesive, usually consisting of fine- and medium-grained or silty sands, sandy loams, interspersed with layers of loams. Massifs under pressure hydraulic structures are quite water-saturated. Soil liquefaction occurs as a result of the destruction of structural bonds between particles in water-saturated dispersed soils under the action of stresses of various types. An external dynamic or static load applied to a water-saturated massif composed of weak, finely dispersed soils can lead to a complete or partial loss of soil bearing capacity and its transition to a fluid state. The magnitude of soil resistance to shear is determined by the degree of its water saturation; at a moisture content of about 20 %, the angle of repose of sandy soils is significantly reduced. The restoration of the strength properties of soils is prevented by the pore water pressure, the process of compaction (consolidation) of the soil mass occurs after the water is squeezed out of the pores, the flow time of which depends on the filtration properties of the massif. Liquefaction of soils leads to a disruption in the normal functioning of a hydraulic structure, the creation of emergency situations. The paper provides examples of accidents at hydraulic structures in Russia caused by liquefaction phenomena. It is noted that the main directions of protecting the structures of hydraulic structures from dangerous liquefaction are to prevent the possibility of liquefaction and the reduction of its harmful effects.  In this regard, several methods are considered – compaction and strengthening of soils at the base of structures; filtering surcharge device using geotextiles and geogrids; creation of an effective drainage system.Представлен анализ вероятности и условий возникновения разжижения грунтов, залегающих в основании и окрестностях гидротехнических сооружений. Как правило, гидротехнические сооружения возводятся в долинах водотоков, структура грунтов в которых способствует возникновению процессов разжижения. Грунты эти мелкофракционные несвязные, состоящие обычно из мелко- и среднезернистых или пылеватых песков, супесей, перемежающихся слоями суглинков. Массивы под напорными гидротехническими сооружениями достаточно водонасыщенные. Разжижение грунтов происходит в результате разрушения структурных связей между частицами в водонасыщенных дисперсных грунтах под действием напряжений разного типа. Внешняя динамическая или статическая нагрузка, приложенная к водонасыщенному массиву, сложенному из слабых мелкодисперсных грунтов, может привести к полной или частичной потере грунтом несущей способности и переходу его в текучее состояние. Величина сопротивления грунта сдвигу определяется степенью его водонасыщенности; при влажности порядка 20 % угол естественного откоса песчаных грунтов существенно уменьшается. Восстановлению прочностных свойств грунтов препятствует поровое давление воды, процесс уплотнения (консолидации) массива грунта происходит после отжатия воды из пор, время протекания которого зависит от фильтрационных свойств массива. Разжижение грунтов приводит к нарушению нормального функционирования гидротехнического сооружения, созданию аварийных ситуаций. В статье представлены примеры возникновения аварий на гидротехнических сооружениях России, вызванных явлениями разжижения. Отмечено, что основные направления защиты конструкций гидротехнических сооружений от опасного разжижения – предотвращение возможности возникновения разжижения и уменьшение его вредных последствий. В этой связи рассмотрено несколько способов – уплотнение и упрочение грунтов в основании сооружений; устройство фильтрующей пригрузки с использованием геотекстиля и георешеток; создание эффективной дренажной (водоотводящей) системы

Wildfires lead to decreased carbon and increased nitrogen concentrations in upland arctic streams

The Central Siberian Plateau is undergoing rapid climate change that has resulted in increased frequency of forest fires and subsequent alteration of watershed carbon and nutrient dynamics. Across a watershed chronosequence (3 to \u3e100 years since wildfire) we quantified the effects of fire on quantity and composition of dissolved organic matter (DOM), stream water nutrient concentrations, as well as in-stream nutrient uptake. Wildfires increased concentrations of nitrate for a decade, while decreasing concentrations of dissolved organic carbon and nitrogen (DOC and DON) and aliphatic DOM contribution for five decades. These post-wildfire changes in stream DOM result in lower uptake efficiency of in-stream nitrate in recently burned watersheds. Nitrate uptake (as uptake velocity) is strongly dependent on DOM composition (e.g. polyphenolics), ambient dissolved inorganic nitrogen (DIN), and DOC to DIN ratios. Our observations and experiments suggest that a decade-long pulse of inorganic nitrogen and a reduction of DOC export occur following wildfires in streams draining the Central Siberian Plateau. Increased fire frequency in the region is thus likely to both decrease DOM and increase nitrate delivery to the main stem Yenisei River, and ultimately the Arctic Ocean, in the coming decades

Fast Photon Detection for Particle Identification with COMPASS RICH-1

Particle identification at high rates is an important challenge for many current and future high-energy physics experiments. The upgrade of the COMPASS RICH-1 detector requires a new technique for Cherenkov photon detection at count rates of several $10^6$ per channel in the central detector region, and a read-out system allowing for trigger rates of up to 100 kHz. To cope with these requirements, the photon detectors in the central region have been replaced with the detection system described in this paper. In the peripheral regions, the existing multi-wire proportional chambers with CsI photocathode are now read out via a new system employing APV pre-amplifiers and flash ADC chips. The new detection system consists of multi-anode photomultiplier tubes (MAPMT) and fast read-out electronics based on the MAD4 discriminator and the F1-TDC chip. The RICH-1 is in operation in its upgraded version for the 2006 CERN SPS run. We present the photon detection design, constructive aspects and the first Cherenkov light in the detector.Comment: Proceedings of the Imaging 2006 conference, Stockholm, Sweden, 27-30 June 2006, 5 pages, 6 figures, to appear in NIM A; corrected typo in caption of Fig.

Fast photon detection for the COMPASS RICH detector

The COMPASS experiment at the SPS accelerator at CERN uses a large scale Ring Imaging CHerenkov detector (RICH) to identify pions, kaons and protons in a wide momentum range. For the data taking in 2006, the COMPASS RICH has been upgraded in the central photon detection area (25% of the surface) with a new technology to detect Cherenkov photons at very high count rates of several 10^6 per second and channel and a new dead-time free read-out system, which allows trigger rates up to 100 kHz. The Cherenkov photons are detected by an array of 576 visible and ultra-violet sensitive multi-anode photomultipliers with 16 channels each. The upgraded detector showed an excellent performance during the 2006 data taking.Comment: Proceeding of the IPRD06 conference (Siena, Okt. 06

The Fast Read-out System for the MAPMTs of COMPASS RICH-1

A fast readout system for the upgrade of the COMPASS RICH detector has been developed and successfully used for data taking in 2006 and 2007. The new readout system for the multi-anode PMTs in the central part of the photon detector of the RICH is based on the high-sensitivity MAD4 preamplifier-discriminator and the dead-time free F1-TDC chip characterized by high-resolution. The readout electronics has been designed taking into account the high photon flux in the central part of the detector and the requirement to run at high trigger rates of up to 100 kHz with negligible dead-time. The system is designed as a very compact setup and is mounted directly behind the multi-anode photomultipliers. The data are digitized on the frontend boards and transferred via optical links to the readout system. The read-out electronics system is described in detail together with its measured performances.Comment: Proceeding of RICH2007 Conference, Trieste, Oct. 2007. v2: minor change

Measurement of the K+→μ+νμγK^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma} decay form factors in the OKA experiment

A precise measurement of the vector and axial-vector form factors difference $F_V-F_A$ in the $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ decay is presented. About 95K events of $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ are selected in the OKA experiment. The result is $F_V-F_A=0.134\pm0.021(stat)\pm0.027(syst)$. Both errors are smaller than in the previous $F_V-F_A$ measurements.Comment: 9 pages, 8 figure