Structural changes in gill DNA reveal the effects of contaminants on Puget Sound fish.

Structural differences were identified in gill DNA from two groups of English sole collected from Puget Sound, Washington, in October 2000. One group was from the industrialized Duwamish River (DR) in Seattle and the other from relatively clean Quartermaster Harbor (QMH). Chemical markers of sediment contamination [e.g., polynuclear aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs)] established that the DR was substantially more contaminated than QMH. The levels of these chemicals in the sediments of both sites were consistent with levels of cytochrome P450 1A (CYP1A) expression in the gills of English sole from the same sites. Structural differences in gill DNA between the groups were evinced via statistical models of Fourier transform-infrared (FT-IR) spectra. Marked structural damage was found in the gill DNA of the DR fish as reflected in differences in base functional groups (e.g., C-O and NH2) and conformational properties (e.g., arising from perturbations in vertical base stacking interactions). These DNA differences were used to discriminate between the two fish groups through principal components analysis of mean FT-IR spectra. In addition, logistic regression analysis allowed for the development of a "DNA damage index" to assess the effects of contaminants on the gill. The evidence implies that environmental chemicals contribute to the DNA changes in the gill. The damaged DNA is a promising marker for identifying, through gill biopsies, contaminant effects on fish

Making collaboration work: application of a conceptual design stages protocol for pre-BIM stages.

This paper presents the application of a Conceptual Design Stages Protocol during feasibility stages within a multidisciplinary design team, for the purpose of bridging the gap between ideas generation and their representation in later and more advanced design stages. Increased effort during the early and conceptual design is a prerequisite for effective and sustainable overall design and construction. Consequently, shift of the effort towards feasibility stages aims to tackle problems with workflow, education and organisation of design teams at the very beginning of a project. Furthermore, the application of an organised process during conceptual design could further support a multi-party agreement, hence enhancing the potentials of collaboration and coordination for the entirety of a project. This paper demonstrates the Conceptual Design Stages Protocol as an organised process encompassing different professionals, technologies and means for communication that has been tested in a conceptual stage study and the outcomes have been incorporated within BIM. The impact of this Protocol on designers cognitive, physical, perceptual and collaborative actions is presented and the first pre-BIM Protocol is established. This was a paper presented at the International Conference on Building Information Modelling (BIM) in Design, Construction and Operations, held in Bristol, 9-11 September 2015

Peptide Ligation–Desulfurization Chemistry at Arginine

The utility of a new β‐thiol arginine building block in ligation–desulfurization chemistry has been demonstrated through reactions and kinetic studies with a range of peptide thioesters. Application of the method is highlighted by a one‐pot, kinetically controlled, rapid ligation to generate a 7 kDa MUC1 glycopeptide

Travelling and sticky affects: : Exploring teens and sexualized cyberbullying through a Butlerian-Deleuzian- Guattarian lens

In this paper we combine the thinking of Deleuze and Guattari (1984, 1987) with Judith Butler’s (1990, 1993, 2004, 2009) work to follow the rhizomatic becomings of young people’s affective relations in a range of on- and off-line school spaces. In particular we explore how events that may be designated as sexual cyberbullying are constituted and how they are mediated by technology (such as texting or in/through social networking sites). Drawing on findings from two different studies looking at teens’ uses of and experiences with social networking sites, Arto in Denmark, and Bebo in the UK, we use this approach to think about how affects flow, are distributed, and become fixed in assemblages. We map how affects are manoeuvred and potentially disrupted by young people, suggesting that in the incidences discussed affects travel as well as stick in points of fixation. We argue that we need to grasp both affective flow and fixity in order to gain knowledge of how subjectification of the gendered/classed/racialised/sexualised body emerges. A Butlerian-Deleuzian-Guattarian frame helps us to map some of these affective complexities that shape sexualized cyberbully events; and to recognize technologically mediated lines of flight when subjectifications are at least temporarily disrupted and new terms of recognition and intelligibility staked out. Keywords

Assessment of the potential in vivo ecotoxicity of Double-Walled Carbon Nanotubes (DWNTs) in water, using the amphibian Ambystoma mexicanum

Because of their specific properties (mechanical, electrical, etc), carbon nanotubes (CNTs) are being assessed for inclusion in many manufactured products. Due to their massive production and number of potential applications, the impact of CNTs on the environment must be taken into consideration. The present investigation evaluates the ecotoxic potential of CNTs in the amphibian larvae (Ambystoma mexicanum). Acute toxicity and genotoxicity were analysed after 12 days of exposure in laboratory conditions. The genotoxic effects were analysed by scoring the micronucleated erythrocytes in the circulating blood of the larvae according to the French standard micronucleus assay. The results obtained in the present study demonstrated that CNTs are neither acutely toxic nor genotoxic to larvae whatever the CNTs concentration in the water, although black masses of CNTs were observed inside the gut. In the increasing economical context of CNTs, complementary studies must be undertaken, especially including mechanistic and environmental investigations

Fluorescent carbon dioxide indicators

Over the last decade, fluorescence has become the dominant tool in biotechnology and medical imaging. These exciting advances have been underpinned by the advances in time-resolved techniques and instrumentation, probe design, chemical / biochemical sensing, coupled with our furthered knowledge in biology. Complementary volumes 9 and 10, Advanced Concepts of Fluorescence Sensing: Small Molecule Sensing and Advanced Concepts of Fluorescence Sensing: Macromolecular Sensing, aim to summarize the current state of the art in fluorescent sensing. For this reason, Drs. Geddes and Lakowicz have invited chapters, encompassing a broad range of fluorescence sensing techniques. Some chapters deal with small molecule sensors, such as for anions, cations, and CO2, while others summarize recent advances in protein-based and macromolecular sensors. The Editors have, however, not included DNA or RNA based sensing in this volume, as this were reviewed in Volume 7 and is to be the subject of a more detailed volume in the near future

Multiwavelength Observations of Supersonic Plasma Blob Triggered by Reconnection Generated Velocity Pulse in AR10808

Using multi-wavelength observations of Solar and Heliospheric Observatory (SoHO)/Michelson Doppler Imager (MDI), Transition Region and Coronal Explorer (TRACE) 171 \AA, and H$\alpha$ from Culgoora Solar Observatory at Narrabri, Australia, we present a unique observational signature of a propagating supersonic plasma blob before an M6.2 class solar flare in AR10808 on 9th September 2005. The blob was observed between 05:27 UT to 05:32 UT with almost a constant shape for the first 2-3 minutes, and thereafter it quickly vanished in the corona. The observed lower bound speed of the blob is estimated as $\sim$215 km s$^{-1}$ in its dynamical phase. The evidence of the blob with almost similar shape and velocity concurrent in H$\alpha$ and TRACE 171 \AA\ supports its formation by multi-temperature plasma. The energy release by a recurrent 3-D reconnection process via the separator dome below the magnetic null point, between the emerging flux and pre-existing field lines in the lower solar atmosphere, is found to be the driver of a radial velocity pulse outwards that accelerates this plasma blob in the solar atmosphere. In support of identification of the possible driver of the observed eruption, we solve the two-dimensional ideal magnetohydrodynamic equations numerically to simulate the observed supersonic plasma blob. The numerical modelling closely match the observed velocity, evolution of multi-temperature plasma, and quick vanishing of the blob found in the observations. Under typical coronal conditions, such blobs may also carry an energy flux of 7.0$\times10^{6}$ ergs cm$^{-2}$ s$^{-1}$ to re-balance the coronal losses above active regions.Comment: Solar Physics; 22 Pages; 8 Figure

Geometric frustration in small colloidal clusters

We study the structure of clusters in a model colloidal system with competing interactions using Brownian dynamics simulations. A short-ranged attraction drives clustering, while a weak, long-ranged repulsion is used to model electrostatic charging in experimental systems. The former is treated with a short-ranged Morse attractive interaction, the latter with a repulsive Yukawa interaction. We consider the yield of clusters of specific structure as a function of the strength of the interactions, for clusters with m=3,4,5,6,7,10 and 13 colloids. At sufficient strengths of the attractive interaction (around 10 kT), the average bond lifetime approaches the simulation timescale and the system becomes nonergodic. For small clusters m<=5 where geometric frustration is not relevant, despite nonergodicity, for sufficient strengths of the attractive interaction the yield of clusters which maximise the number of bonds approaches 100%. However for $m=7$ and higher, in the nonergodic regime we find a lower yield of these structures where we argue geometric frustration plays a significant role. $m=6$ is a special case, where two structures, of octahedral and C2v symmetry compete, with the latter being favoured by entropic contributions in the ergodic regime and by kinetic trapping in the nonergodic regime. We believe that our results should be valid as far as the one-component description of the interaction potential is valid. A system with competing electrostatic repulsions and van der Waals attractions may be such an example. However, in some cases, the one-component description of the interaction potential may not be appropriate.Comment: 21 pages, accepted for publication by J. Phys. Condens. Matte