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Mucus is a self-healing gel that lubricates the moist epithelium and provides protection against viruses by binding to viruses smaller than the gel’s mesh size and removing them from the mucosal surface by active mucus turnover. As the primary nonaqueous components of mucus (≈0.2%–5%, wt/v), mucins are critical to this function because the dense arrangement of mucin glycans allows multivalence of binding. Following nature’s example, bovine submaxillary mucins (BSMs) are assembled into “mucus-like” gels (5%, wt/v) by dynamic covalent crosslinking reactions. The gels exhibit transient liquefaction under high shear strain and immediate self-healing behavior. This study shows that these material properties are essential to provide lubricity. The gels efficiently reduce human immunodeficiency virus type 1 (HIV-1) and genital herpes virus type 2 (HSV-2) infectivity for various types of cells. In contrast, simple mucin solutions, which lack the structural makeup, inhibit HIV-1 significantly less and do not inhibit HSV-2. Mechanistically, the prophylaxis of HIV-1 infection by BSM gels is found to be that the gels trap HIV-1 by binding to the envelope glycoprotein gp120 and suppress cytokine production during viral exposure. Therefore, the authors believe the gels are promising for further development as personal lubricants that can limit viral transmission., QC 20221216

In the present study, the decolourization efficiencies of LP-Hg lamp, XeCl and KrCl excilamps at the same power density were compared for the decolourization of dyes in water by UV and UV/H2O2 processes in a batch reactor. Laboratory prototypes of XeCl and KrCl excilamps and a commercial LP-Hg lamp were studied as UV sources. Methylene Blue and Eliamine Blue dyes were used as model pollutants. The effect of the initial concentrations of dye and H2O2 in the TOC removal and kinetic parameters were also studied. The ratio of dye decolourization to the electric power consumption of the KrCl excilamp and LP-Hg lamp for the decolourization of Methylene Blue and Eliamine Blue were evaluated. As a result, the KrCl excilamp showed significantly higher decolourization efficiencies than LP-Hg lamp and XeCl excilamp, but the dye removal rate was significantly slower for Methylene Blue than for Eliamine Blue with this lamp. The KrCl lamp can be an alternative to conventional LP-Hg lamp for the decolourization of dyes by photodegradation, but it depends on the type of dye treated. The addition of H2O2 in a concentration between 0.05 and 0.09%v/v increases significantly the efficiency of the decolourization of Methylene Blue, and further increase does not lead to a higher increase in conversion. The experimental data were fitted to the one phase decay kinetic model with good agreement and the kinetic parameters were reported. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.

The last section of the Porto Metro light rail tunnel, Portugal, is under the city centre, with 2.6 to 5 m cover of highly weathered granite and soil, below extremely sensitive buildings. Risk assessment led to buildings being protected by heavy ground treatment, internal and external building support, or a fore-poling umbrella and fibre-bolts. The design proposals and final scheme are described. Excavation by tunnel boring machine was uneventful, without significant damage to buildings despite the sensitivity of the ground., The last section of the Porto Metro light rail tunnel, Portugal, is under the city centre, with 2.6 to 5 m cover of highly weathered granite and soil, below extremely sensitive buildings. Risk assessment led to buildings being protected by heavy ground treatment, internal and external building support, or a fore-poling umbrella and fibre-bolts. The design proposals and final scheme are described. Excavation by tunnel boring machine was uneventful, without significant damage to buildings despite the sensitivity of the ground.

A review of the framework designer, Mott MacDonald's, contract (C121) for sprayed concrete lining (SCL) works for the tunnels, caverns and shafts across the Crossrail project, London, UK is presented. Assignment of design responsibility for temporary and permanent SCL works is discussed and a description of the lining configuration - primary lining, waterproofing membrane and secondary lining - is provided. Design methodology for the proposed lining system - a double shell with both linings regarded as part of the load-bearing structure - includes 2- and 3-D numerical modelling (FLAC or FLAC3D) of the primary lining and determination of secondary lining forces using 2- and 3-D computer structural models based on the centroid of the tunnel-lining cross-section. Typical performance requirements for the Crossrail SCL tunnels and suggested improvements resulting from knowledge acquired during execution of the contract are summarised., A review of the framework designer, Mott MacDonald's, contract (C121) for sprayed concrete lining (SCL) works for the tunnels, caverns and shafts across the Crossrail project, London, UK is presented. Assignment of design responsibility for temporary and permanent SCL works is discussed and a description of the lining configuration - primary lining, waterproofing membrane and secondary lining - is provided. Design methodology for the proposed lining system - a double shell with both linings regarded as part of the load-bearing structure - includes 2- and 3-D numerical modelling (FLAC or FLAC3D) of the primary lining and determination of secondary lining forces using 2- and 3-D computer structural models based on the centroid of the tunnel-lining cross-section. Typical performance requirements for the Crossrail SCL tunnels and suggested improvements resulting from knowledge acquired during execution of the contract are summarised.

A calculation method has been developed that, despite its simplicity, mirrors the physical phenomena closely. Rather than resort to iterative procedures it relies on an exact expression in which the parameter values are easily ascertained from in-situ air flow measurements. The basic assumption, that the leakage flow rate over a piece of ductwork is constantly proportional to the circulating flow rate, allows the method to reach an explicit solution such that any problem can be solved by a straightforward procedure. The accuracy of the methodology has been checked by correlation against actual measurements obtained in underground operations. It has also been written in the form of a computer program., A calculation method has been developed that, despite its simplicity, mirrors the physical phenomena closely. Rather than resort to iterative procedures it relies on an exact expression in which the parameter values are easily ascertained from in-situ air flow measurements. The basic assumption, that the leakage flow rate over a piece of ductwork is constantly proportional to the circulating flow rate, allows the method to reach an explicit solution such that any problem can be solved by a straightforward procedure. The accuracy of the methodology has been checked by correlation against actual measurements obtained in underground operations. It has also been written in the form of a computer program.

Results are presented for a 45 kW, 15 t roadheader excavating two different types of rock using two different cutting heads. It is shown that the roadheader functioned correctly with both heads and that its specific energy, cutting rate and tool wear were all at a satisfactory level when the machine's low power was taken into consideration. The main difference between the two heads was the number of cutters on each. The 24-pick head achieved a 20% faster cutting rate than the 36-pick head with less specific energy consumption, but its tool consumption was 40-50% greater and there was a greater level of vibration., Results are presented for a 45 kW, 15 t roadheader excavating two different types of rock using two different cutting heads. It is shown that the roadheader functioned correctly with both heads and that its specific energy, cutting rate and tool wear were all at a satisfactory level when the machine's low power was taken into consideration. The main difference between the two heads was the number of cutters on each. The 24-pick head achieved a 20% faster cutting rate than the 36-pick head with less specific energy consumption, but its tool consumption was 40-50% greater and there was a greater level of vibration.

Convergence was measured in order to design a new roadway support system in a mine. Analysis of the results showed that rock-mass discontinuities were very important to the final convergence, with and without longwall influence. From these measurements two finite-element method (FEM) models were calibrated to study the interaction between rock mass and support. In the first model the materials were in continuum and in the other discontinuities were simulated. Both models represented very accurately real phenomena under mining conditions of a closely jointed rock mass and high stress at Carbonar coal mine in Spain., Convergence was measured in order to design a new roadway support system in a mine. Analysis of the results showed that rock-mass discontinuities were very important to the final convergence, with and without longwall influence. From these measurements two finite-element method (FEM) models were calibrated to study the interaction between rock mass and support. In the first model the materials were in continuum and in the other discontinuities were simulated. Both models represented very accurately real phenomena under mining conditions of a closely jointed rock mass and high stress at Carbonar coal mine in Spain.

A methodology originally developed for mine roadway ventilation is introduced for the calculation of general tunnel ventilation cases. The accuracy of the derived computer program is demonstrated by comparing its results with those drawn from experience., A methodology originally developed for mine roadway ventilation is introduced for the calculation of general tunnel ventilation cases. The accuracy of the derived computer program is demonstrated by comparing its results with those drawn from experience.

Shallow gas reservoirs in marine sediments from the Iberian margin or their escapes can be detected by using direct methods: measurement of high concentrations of methane or other hydrocarbons in the water column or sediment cores; identification of chemosynthetic communities and/or authigenic carbonates in the seafloor; and identification, using underwater videos, of pockmarks or carbonate mounds and mud volcanoes associated with the fluid escapes. Among indirect characterisation methods of anomalies in acoustic records are: presence of acoustic plumes in echo-sounders records; identification of acoustic blanking and/or acoustic turbidity in the high resolution seismic records; interpretation of reflectivity; and, morphologies of pockmarks or seamounts in sidescan sonar and multibeam echosounder records. This article is a compilation of acoustic-seismic, sedimentologic and morphologic evidence associated with the presence of shallow gas accumulations or escapes that appear in the Iberian margin and have been published in various papers. The description is divided into geographical sectors, beginning in the northeastern end of the Mediterranean margin and ending at the easternmost area of the Cantabrian margin, following a clockwise direction around the Iberian Peninsula., Shallow gas reservoirs in marine sediments from the Iberian margin or their escapes can be detected by using direct methods: measurement of high concentrations of methane or other hydrocarbons in the water column or sediment cores; identification of chemosynthetic communities and/or authigenic carbonates in the seafloor; and identification, using underwater videos, of pockmarks or carbonate mounds and mud volcanoes associated with the fluid escapes. Among indirect characterisation methods of anomalies in acoustic records are: presence of acoustic plumes in echo-sounders records; identification of acoustic blanking and/or acoustic turbidity in the high resolution seismic records; interpretation of reflectivity; and, morphologies of pockmarks or seamounts in sidescan sonar and multibeam echosounder records. This article is a compilation of acoustic-seismic, sedimentologic and morphologic evidence associated with the presence of shallow gas accumulations or escapes that appear in the Iberian margin and have been published in various papers. The description is divided into geographical sectors, beginning in the northeastern end of the Mediterranean margin and ending at the easternmost area of the Cantabrian margin, following a clockwise direction around the Iberian Peninsula.