Trees and wood: working with natural river processes

A history of land clearance and riparian tree and wood management has resulted in limited riparian woodland and wood along British rivers. However, river management approaches are now being promoted that ‘work with natural processes’ to reduce flood risk through measures intended to restore, protect and emulate the natural function of catchments, rivers, estuaries and coasts. Wood has started to be reintroduced into river channels during river restoration and natural flood management activities, but this needs to be undertaken using appropriate quantities, locations and designs that mimic natural tree‐wood features. This paper reviews the knowledge that is needed to support wood reintroduction activities including (i) the characteristics of the riparian tree species and wood that are present; (ii) the importance of river size relative to that of trees and wood pieces; and (iii) the way trees, wood and geomorphic processes interact across rivers and floodplains of different energy and style.     

Review

Richard Mabey, Home Country London: Century 1990 £14.95

A Tour of the Lakes in Cumberland. John Ruskin's Diary for 1830. James S. Dearden, (Ed.), with an Introduction by Van Akin Burd. Scolar Press, Aldershot, 1990.

The Landscape Vision of Paul Nash, Roger Cardinal. Reaktion Books, London, 1989. £9,95 paperback ISBN 0948462 02 7

M G R Cannell & M D Hooper, The Greenhouse Effect and Terrestrial Ecosystems of the UK London, HMSO, 1990. 56pp. £4.95

Amenity In Action, The Civic Trust Handbook of Community Initiatives compiled & edited by Deirdre Genet, Societies Development Officer, The Civic Trust (1989), (supported by the Shell Better Britain Campaign)

Sue Minter The Greatest Glass House: The rainforests recreated HMSO, 1990. £25.00     

Moment-rotation-temperature curves for semi-rigid joints

Although connections are known to have a very significant effect on the behaviour of steel and composite framed buildings in the event of fire, the cost of high temperature tests on the broad range of connections used in practice means that their influence is not well detailed in current design codes. The paucity of data also limits the effective use of numerical models developed to simulate the behaviour of complete structures at elevated temperature. This research describes a series of elevated temperature tests conducted on beam-to-column connections. This paper presents moment-rotation-temperature curves for a variety of connections.     

Inactivation efficacy of plasma-activated water: influence of plasma treatment time,exposure time and bacterial species

This study aimed to evaluate the influence of plasma treatment time, bacterial exposure time to PAW and bacterial species on the inactivation efficacy of plasma-activated water (PAW), with additional investigation of the inactivation mechanisms of PAW. Six bacterial species, including Listeria innocua, Staphyloccus aureus, Escherichia coli, Pseudomonas fluorescens, Shewanella putrefaciens and Aeromonas hydrophila were selected as the representative bacteria. The initial bacterial concentration was around 7 log CFU ml⁻¹ after mixing with PAW, and the inactivation efficacy was measured after different exposure times during the 4 °C storage. Scanning electron microscopy (SEM) images of the bacteria after PAW treatment were carried out to inspect the cell structure damage, and physicochemical properties of PAW, including pH, conductivity and long-living reactive species of H₂O₂, , and , were examined. The results showed that the inactivation efficacy of PAW was positively correlated with plasma treatment time and bacterial exposure time, and for the species examined in this study, the Gram-negative species were more sensitive to PAW than the Gram-positive species. Cell structure damage, including shrinkage, distortion, or holes, was observed after PAW treatment. The pH of PAW was acidified to 2.5–2.9, and conductivity was significantly increased to 518.0 μs cm⁻¹. and H₂O₂ were reduced during the 48 h storage, while an increased concentration was observed for . This study demonstrated that the processing parameters of plasma treatment time, exposure time and characteristics of bacteria can significantly affect the inactivation efficacy of PAW.     

Development of a creep‐free stress‐strain law for fire analysis of steel structures

This paper presents a practical procedure for obtaining creep‐free stress‐strain laws for steel exposed to fire, on the basis of codified stress‐strain laws that consider creep implicitly. The applicability of the proposed procedure has been tested on two commonly used stress‐strain laws for steel at elevated temperature, the Eurocode 3 law and a Ramberg–Osgood model, both of which have implicit consideration of creep. The simulation of two published steel coupon experiments on steel of grades S275 and S355 shows that both the Eurocode and Ramberg–Osgood stress‐strain laws produce inaccurate predictions of creep in fire at elevated temperatures. The proposed procedure was thereby used to extract the implicit creep according to the heating rates of the transient coupon tests and to derive the creep‐free stress‐strain laws. It has been shown that, by combining the creep‐free stress strain law obtained by the proposed methodology with an explicit creep model, a more realistic prediction of steel behaviour in the selected coupon test studies can be achieved. Copyright © 2015 John Wiley & Sons, Ltd.     

In Vivo Studies of Nanostructure‐Based Photosensitizers for Photodynamic Cancer Therapy

Animal models, particularly rodents, are major translational models for evaluating novel anticancer therapeutics. In this review, different types of nanostructure‐based photosensitizers that have advanced into the in vivo evaluation stage for the photodynamic therapy (PDT) of cancer are described. This article focuses on the in vivo efficacies of the nanostructures as delivery agents and as energy transducers for photosensitizers in animal models. These materials are useful in overcoming solubility issues, lack of tumor specificity, and access to tumors deep in healthy tissue. At the end of this article, the opportunities made possible by these multiplexed nanostructure‐based systems are summarized, as well as the considerable challenges associated with obtaining regulatory approval for such materials. The following questions are also addressed: (1) Is there a pressing demand for more nanoparticle materials? (2) What is the prognosis for regulatory approval of nanoparticles to be used in the clinic?     

Three-dimensional analysis of the spatial distribution of iron oxide particles in a decorative coating by electron microscopic imaging

The three-dimensional (3D) spatial structure of an iron oxide containing alkyd paint specimen has been investigated by serial block-face scanning electron microscopy (SBFSEM). The resultant images of the 3D structure clearly present the spatial distribution of the iron oxide pigment particles in the coating film and reveal the extent of aggregation of the particles in the matrix material. More than one-half of the iron oxide particles (in volume) had aggregated to form clusters of considerable sizes that follow a Gaussian spacing distribution in the measured coating film. Over 80% of the clusters have dimensions between 1.5 μm and 3.5 μm; also, pores are evident at the centres of clusters whose sizes are larger than 2 μm. The work demonstrated here reveals a new approach to fully characterize the 3D spatial structure of coatings and to explore their correlations with the performance of the materials.