Mining electron density for functionally relevant protein polysterism in crystal structures.

This review focuses on conceptual and methodological advances in our understanding and characterization of the conformational heterogeneity of proteins. Focusing on X-ray crystallography, we describe how polysterism, the interconversion of pre-existing conformational substates, has traditionally been analyzed by comparing independent crystal structures or multiple chains within a single crystal asymmetric unit. In contrast, recent studies have focused on mining electron density maps to reveal previously 'hidden' minor conformational substates. Functional tests of the importance of minor states suggest that evolutionary selection shapes the entire conformational landscape, including uniquely configured conformational substates, the relative distribution of these substates, and the speed at which the protein can interconvert between them. An increased focus on polysterism may shape the way protein structure and function is studied in the coming years

Evaluation of Lumicyano cyanoacrylate fuming process for the development of latent fingermarks on plastic carrier bags by means of a pseudo operational comparative trial

There are a number of studies discussing recent developments of a one-step fluorescent cyanoacrylate process. This study is a pseudo operational trial to compare an example of a one-step fluorescent cyanoacrylate product, Lumicyano™, with the two recommended techniques for plastic carrier bags; cyanoacrylate fuming followed by basic yellow 40 (BY40) dyeing and powder suspensions. 100 plastic carrier bags were collected from the place of work and the items were treated as found without any additional fingermark deposition. The bags were split into three and after treatment with the three techniques a comparable number of fingermarks were detected by each technique (average of 300 fingermarks). The items treated with Lumicyano™ were sequentially processed with BY40 and an additional 43 new fingermarks were detected. Lumicyano™ appears to be a suitable technique for the development of fingermarks on plastic carrier bags and it can help save lab space and time as it does not require dyeing or drying procedures. Furthermore, contrary to other one-step cyanoacrylate products, existing cyanoacrylate cabinets do not require any modification for the treatment of articles with Lumicyano™. To date, there is little peer reviewed articles in the literature on trials related to Lumicyano™ and this study aims to contribute to fill this gap

Origins of the avian neural crest: the role of neural plate-epidermal interactions

We have investigated the lineage and tissue interactions that result in avian neural crest cell formation from the ectoderm. Presumptive neural plate was grafted adjacent to non-neural ectoderm in whole embryo culture to examine the role of tissue interactions in ontogeny of the neural crest. Our results show that juxtaposition of non-neural ectoderm and presumptive neural plate induces the formation of neural crest cells. Quail/chick recombinations demonstrate that both the prospective neural plate and the prospective epidermis can contribute to the neural crest. When similar neural plate/epidermal confrontations are performed in tissue culture to look at the formation of neural crest derivatives, juxtaposition of epidermis with either early (stages 4–5) or later (stages 6–10) neural plate results in the generation of both melanocytes and sympathoadrenal cells. Interestingly, neural plates isolated from early stages form no neural crest cells, whereas those isolated later give rise to melanocytes but not crest-derived sympathoadrenal cells. Single cell lineage analysis was performed to determine the time at which the neural crest lineage diverges from the epidermal lineage and to elucidate the timing of neural plate/epidermis interactions during normal development. Our results from stage 8 to 10+ embryos show that the neural plate/neural crest lineage segregates from the epidermis around the time of neural tube closure, suggesting that neural induction is still underway at open neural plate stages

The effect of finite field size on classification and atmospheric correction

The atmospheric effect on the upward radiance of sunlight scattered from the Earth-atmosphere system is strongly influenced by the contrasts between fields and their sizes. For a given atmospheric turbidity, the atmospheric effect on classification of surface features is much stronger for nonuniform surfaces than for uniform surfaces. Therefore, the classification accuracy of agricultural fields and urban areas is dependent not only on the optical characteristics of the atmosphere, but also on the size of the surface do not account for the nonuniformity of the surface have only a slight effect on the classification accuracy; in other cases the classification accuracy descreases. The radiances above finite fields were computed to simulate radiances measured by a satellite. A simulation case including 11 agricultural fields and four natural fields (water, soil, savanah, and forest) was used to test the effect of the size of the background reflectance and the optical thickness of the atmosphere on classification accuracy. It is concluded that new atmospheric correction methods, which take into account the finite size of the fields, have to be developed to improve significantly the classification accuracy

The horizon problem for prevalent surfaces

We investigate the box dimensions of the horizon of a fractal surface defined by a function $f \in C[0,1]^2$. In particular we show that a prevalent surface satisfies the `horizon property', namely that the box dimension of the horizon is one less than that of the surface. Since a prevalent surface has box dimension 3, this does not give us any information about the horizon of surfaces of dimension strictly less than 3. To examine this situation we introduce spaces of functions with surfaces of upper box dimension at most \alpha, for \alpha $\in$ [2,3). In this setting the behaviour of the horizon is more subtle. We construct a prevalent subset of these spaces where the lower box dimension of the horizon lies between the dimension of the surface minus one and 2. We show that in the sense of prevalence these bounds are as tight as possible if the spaces are defined purely in terms of dimension. However, if we work in Lipschitz spaces, the horizon property does indeed hold for prevalent functions. Along the way, we obtain a range of properties of box dimensions of sums of functions

Construction and testing of self-drilled soil nails

Current standards and best practice guidance recognise that testing of self-drilled hollow bar soil nails can be problematic as conventional packers and debonded lengths cannot be constructed. As a result, this causes difficulty in testing and confirming the ultimate bond resistance within the passive zone of a soil-nailed slope, and thus the design soil nail lengths. This paper provides a summary and review of the various testing procedures adopted for a soil nail construction project in Scotland. The practical design considerations, and their validation through the installation and testing of 49 sacrificial test nails, are detailed. The construction issues associated with the nail installation and testing are also outlined and discussed in light of the results obtained using different testing approaches. The aim of this case study is to report on the experiences with installation and testing of hollow bar soil nails. The objectives are to develop an initial data base of available soil–grout bond strength of hollow bar soil nails based on the several practical installation procedures used in this project and to establish areas for improvement of installation, testing and quality control in order to perform comparable pullout tests on self-drilled hollow bar soil nails. </jats:p

Pseudo-operational trials of Lumicyano solution and Lumicyano powder for the detection of latent fingermarks on various substrates

This study presents pseudo-operational trials comparing a one-step fluorescent cyanoacrylate process with a number of other enhancement techniques on a variety of substrates. This one-step process involves a product, 4% Lumicyano, which is a solution consisting of 4% by weight of a powdered dye (Lumicyano powder) dissolved in a cyanoacrylate-based solution (Lumicyano solution). The cyanoacrylate in the Lumicyano solution may be of a higher quality than that used in the two-step products.One hundred items were collected from the place of work for each trial. Trial 1 involved a comparison of 4% Lumicyano with the conventional two-step cyanoacrylate fuming-dye staining for the detection of latent fingermarks on plastic carrier bags. Trial 2 assessed the quality of the Lumicyano solution (with no powdered dye) but used in a two-step process with basic yellow 40 (BY40). Trial 1, using 4% Lumicyano powder and traditional cyanoacrylate → BY40 detected a similar amount of fingermarks (~295); however, sequential BY40 treatment (i.e., after 4% Lumicyano) detected an additional 30% marks. Trial 2 resulted in the detection of 565 marks after Lumicyano solution → BY40 in comparison to 489 marks after traditional cyanoacrylate fuming and BY40 staining. Trials 3 through 5 compared 4% Lumicyano, 1,2-indanedione-zinc, and ninhydrin on junk mail, magazines, and cardboard used for food or cosmetic packaging; the detection rate was low for all techniques and substrates. Trial 6 on cardboard packaging using 4% Lumicyano, black iron-oxide powder suspension, and magnetic powder also provided a low detection rate. Trial 7, using 4% Lumicyano → BY40, solvent black 3, and iron-oxide powder suspensions on cardboard packaging from a fast food chain, indicated that 4% Lumicyano → BY40 might be a suitable alternative to solvent black 3 and iron-oxide powder suspensions for suspected greasy marks