Explosion Resistance Of Reinforced Concrete Refuge Alternative Wall Under Certain Abutment Loading

Build-in-place (BIP) refuge alternatives (RAs) are used to provide safe havens for miners unable to escape their working area after an accident like an explosion. These underground infrastructures are built over time in various locations and might expose to mining-induced stresses. The convergences related to these stress redistributions around the mine openings might change their structural integrity and, subsequently, the explosion resistivity. Studying the effect of increasing vertical load like abutment stress on such underground mine stopping for the explosion resistance is difficult because repetitive explosion experiments on these structures are perilous and challenging. This study uses two case studies to simulate the real-time monitored abutment loading condition and the explosion testing on such steel-reinforced underground structures. A BIP RA design\u27s performance and failure analysis were evaluated under these two conditions using 3DEC, a three-dimensional distinct element solver. This study aims to reveal the effects of vertical convergence due to panel extraction on the explosion resistance of such reinforced concrete walls. The model results demonstrate that the abutment loaded stopping shows higher deformation during and after the explosion than the models without excessive vertical loads. The stopping has high displacement levels at the top of the structure, resulting in the highest deformation zones being extremely distinctive

Distinct Element Analysis Of Various Structural Element Responses For Coal Rib Support Simulation

Understanding the bolt responses for the efficacy of bolt performance during coal rib support applications plays a key role in controlling the stability of underground coal mine openings. Conducting pull-out tests is imperative to gain a better understanding of these responses. Field conditions such as block volume and degree of cleating may significantly impact bolt performance. These field conditions can be efficiently implemented in numerical modeling approaches, and selecting a proper structural element type for these numerical studies is crucial. This study developed a pull-out test model and compared the performance of structural elements as support members in the coal rib model using 3DEC, a three-dimensional distinct element-based numerical modeling code. This study covered commonly utilized cable, pile, and hybrid structural elements in rib models with explicitly introduced face cleats. The bolt response of numerical models was calibrated with the field data showing the load-displacement response of a pull-out test. Comparing the rib models with these structural elements showed that hybrid structural elements demonstrated better agreement with the field observation as they can simulate the reaction to shearing along the discontinuities by inducing bending stresses. The impact of support density on rib stability is also presented in this study

SWI/SNF senses carbon starvation with a pH-sensitive low complexity sequence [preprint]

It is increasingly appreciated that intracellular pH changes are important biological signals. This motivates the elucidation of molecular mechanisms of pH-sensing. We determined that a nucleocytoplasmic pH oscillation was required for the transcriptional response to carbon starvation in S. cerevisiae. The SWI/SNF chromatin remodeling complex is a key mediator of this transcriptional response. We found that a glutamine-rich low complexity sequence (QLC) in the SNF5 subunit of this complex, and histidines within this sequence, were required for efficient transcriptional reprogramming during carbon starvation. Furthermore, the SNF5 QLC mediated pH-dependent recruitment of SWI/SNF to a model promoter in vitro. Simulations showed that protonation of histidines within the SNF5 QLC lead to conformational expansion, providing a potential biophysical mechanism for regulation of these interactions. Together, our results indicate that that pH changes are a second messenger for transcriptional reprogramming during carbon starvation, and that the SNF5 QLC acts as a pH-sensor

New tetracyclic heteroaromatic compounds based on dehydroamino acids : photophysical and electrochemical studies of interaction with DNA

A benzothienoindole (BTIN) and a benzofuroindole (BFIN) were synthesized in high yields, as potential new target DNA compounds, using a metal-assisted intramolecular C-N cyclization, developed by us, of the methyl esters of N-(t-butoxycarbonyl)-b,b-bis(dibenzothien-4-yl or dibenzofuro-4-yl)dehydroalanines. The latter were obtained by a bis-Suzuki coupling of a b,b-dibromodehydroalanine with the corresponding heteroarylboronic acids. The absorption and fluorescence properties of the novel tetracyclic heteroaromatic compounds were studied in different solvents and in the presence of natural double-stranded (ds) salmon sperm DNA. The results in several solvents show that either BTIN or BFIN can be used as fluorescence solvent sensitive probes. Spectroscopic studies of the interaction of both compounds with dsDNA allowed to determine binding constant (Ki) values and binding site sizes (n). Fluorescence quenching experiments using iodide ion allowed the determination of the accessibilities to the quencher, showing that intercalation is the preferred mode of binding of these molecules to DNA. From the results obtained BTIN is the more intercalative compound and has a higher affinity to DNA. The interaction of this more promising compound with DNA was also studied electrochemically, by using differential pulse voltammetry (DPV) in connection with disposable pencil graphite electrode (PGE). These studies are based on the differences in the BTIN and adenine oxidation signals. After the interaction of BTIN with DNA, the oxidation signals of BTIN and adenine strongly decreased. The latter was attributed to the binding of the BTIN to DNA and the former points to a possible damage of the oxidizable groups of the compound after intercalation into DNA. Several concentrations of BTIN were tested and 50 μg/mL was found to be the optimum concentration in order to detect its interaction with DNA. In addition, the detection limit and the reproducibility were determined by using a disposable electrochemical transducer. The results of spectroscopic and electrochemical detection of BTIN interaction with DNA are in good agreement.Academy of Pharmacists and Turkish Pharmacists Association (TEB)Turkish Academy of Sciences - Young Scientist Award Program (KAE/TUBA-GEBIP/2001-2-8)FEDERFundação para a Ciência e a Tecnologia (FCT) - Projecto POCI/QUI/59407/2004. A.S.A. acknowledges a post-doc. grant SFRH/BPD/24548/2005, Bolsa SFRH/BPD/24548/2005.Scientific and Technical Research Council of Turkey (TUBITAK)

Screening of antioxidant properties of the apple juice using the front-face synchronous fluorescence and chemometrics

Fluorescence spectroscopy is gaining increasing attention in food analysis due to its higher sensitivity and selectivity as compared to other spectroscopic techniques. Synchronous scanning fluorescence technique is particularly useful in studies of multi-fluorophoric food samples, providing a further improvement of selectivity by reduction in the spectral overlapping and suppressing light-scattering interferences. Presently, we study the feasibility of the prediction of the total phenolics, flavonoids, and antioxidant capacity using front-face synchronous fluorescence spectra of apple juices. Commercial apple juices from different product ranges were studied. Principal component analysis (PCA) applied to the unfolded synchronous fluorescence spectra was used to compare the fluorescence of the entire sample set. The regression analysis was performed using partial least squares (PLS1 and PLS2) methods on the unfolded total synchronous and on the single-offset synchronous fluorescence spectra. The best calibration models for all of the studied parameters were obtained using the PLS1 method for the single-offset synchronous spectra. The models for the prediction of the total flavonoid content had the best performance; the optimal model was obtained for the analysis of the synchronous fluorescence spectra at Delta lambda = 110 nm (R (2) = 0.870, residual predictive deviation (RPD) = 2.7). The optimal calibration models for the prediction of the total phenolic content (Delta lambda = 80 nm, R (2) = 0.766, RPD = 2.0) and the total antioxidant capacity (Delta lambda = 70 nm, R (2) = 0.787, RPD = 2.1) had only an approximate predictive ability. These results demonstrate that synchronous fluorescence could be a useful tool in fast semi-quantitative screening for the antioxidant properties of the apple juices.info:eu-repo/semantics/publishedVersio

A Large Hadron Electron Collider at CERN

This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb$^{-1}$. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC

ERS International Congress 2022: highlights from the Respiratory Clinical Care and Physiology Assembly

It is a challenge to keep abreast of all the clinical and scientific advances in the field of respiratory medicine. This article contains an overview of the laboratory-based science, clinical trials and qualitative research that were presented during the 2022 European Respiratory Society International Congress within the sessions from the five groups of Assembly 1 (Respiratory Clinical Care and Physiology). Selected presentations are summarised from a wide range of topics: clinical problems, rehabilitation and chronic care, general practice and primary care, mobile/electronic health (m-health/e-health), clinical respiratory physiology, exercise and functional imaging