Surface-Enhanced Raman Evidence of Protonation, Reorientation, and Ag+ Complexation of Deoxyadenosine and Deoxyadenosine-5 '-Monophosphate (dAMP) on Ag and Au Surfaces

Surface-enhanced Raman (SERS) spectra of deoxyadenosine and 5'-dAMP on Ag and Au surfaces showed the protonation of both compounds in the N1 position, their orientation geometry on metal surfaces, and the formation of Ag+ complexes at alkaline pH on hydroxylamine-reduced Ag colloids. Interestingly, substitution at the N9 position caused dramatic changes in the relative band intensities within the spectra of both deoxyadenosine and 5'-dAMP compared to that of simple adenine, although they continued to be dominated by adenine vibrations. Concentration-dependent spectra of 5'-dAMP were observed, which matched that of adenine at high concentrations and that of deoxyadenosine at lower concentration (

DNA Reorientation on Au Nanoparticles: Label-Free Detection of Hybridization by Surface Enhanced Raman Spectroscopy

DNA sequences attached to Au nanoparticles via thiol linkers stand up from the surface, giving preferential enhancement of the adenine ring breathing SERS band. Non-specific binding via the nucleobases reorients the DNA, reducing this effect. This change in intensity on reorientation was utilised for label-free detection of hybridization of a molecular beacon.

SEPT9_v4 expression induces morphological change, increased motility and disturbed polarity

Several lines of evidence indicate that altered expression of SEPT9 is seen in human neoplasia. In particular there is evidence of altered expression of the SEPT9_v4 isoform. The functional consequences of this remain unclear. We have studied the expression of wild-type- and GTP-binding mutants (G144V and S148N) of the SEPT9_v4 isoform in the MCF7 cell line as a model for its deregulation in neoplasia. We find that SEPT9_v4 expression induces dramatic actin cytoskeletal reorganization with the formation of processes around the cell periphery. Expression of the SEPT9_v4 isoform and a G144V mutant cause delocalization of endogenous SEPT9 from filamentous structures but the S148N mutant does not have this effect. In addition SEPT9_v4 isoform expression enhances cell motility and is associated with perturbation of directional movement. Expression of SEPT9_v4 GTP binding mutants also has potent effects on morphology and motility and causes loss of normal polarity, as judged by Golgi reorientation assays. The phenotypes induced by expression of the SEPT9_v4 isoform and the GTP mutants provide an insight into possible mechanisms of SEPT9_v4 function and suggest that the GTPase functions have both ras- and rab-like features. We propose a model in which overexpression of the SEPT9_v4 isoform in neoplasia is associated with perturbation of SEPT9 complexes, leading to phenotypes associated with neoplasia. Copyright (c) 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Simplified theory of wideband spectra of liquid H2O and D2O (from 0 to 1000 cm(-1)) due to reorienting polar and vibrating H-bonded water molecules

A semi-phenomenological molecular model is presented, which is capable of describing with the use of analytical formulae, the wideband dielectric(1) and far-infrared spectra of ordinary and heavy water. In the model the vector of a dipole moment is presented as a sum of two components. The absolute value of the first one is constant; the second one changes harmonically with time. The key aspect of this work is consideration of FIR spectra due to the second component. In the context of the modified hybrid model presented in the work, reorientation of the dipoles in the rectangular potential well is considered, as a result of which the librational (near 700 cm (-1)) and translational (near 200 cm (-1)) absorption bands and the microwave Debye relaxation spectrum arise. It is shown that the time-dependent part of a dipole moment contributes most to the translational band, the relevant mechanism is taken to be stretching vibration of the H-bonded molecules. Previous linear-response molecular models were unsuccessful in describing this band (in heavy water) in terms of the complex dielectric permittivity. The spatial and time scales characteristic of water are estimated. (C) 2002 Elsevier Science B.V. All rights reserved.

Nonharmonic transverse vibration of the H-bonded molecules and the THz spectra in ice and water

A nonlinear equation of motion is found for the dimer comprising two charged H2O molecules. The THz dielectric response to nonharmonic vibration of a nonrigid dipole, forming the hydrogen bond (HB), is found in the direction transverse to this bond. An explicit expression is derived for the autocorrelator that governs the spectrum generated by transverse vibration (TV) of such a dipole. This expression is obtained by analytical solution of the truncated set of recurrence equations. The far infrared (FIR) spectra of ice at the temperature - 7 degrees C are calculated. The wideband, in the wavenumber (frequency) v range 0... 100.0 cm(-1), spectra are obtained for liquid water at room temperature and for supercooled water at -5.6 degrees C. All spectra are represented in terms of the complex permittivity epsilon(v) and the absorption coefficient alpha(v). The obtained analytical formula for epsilon comprises the term epsilon(perpendicular to) pertinent to the studied TV mechanism with three additional terms Delta epsilon(q), Delta epsilon(mu), and epsilon(or) arising, respectively, from: elastic harmonic vibration of charged molecules along the H-bond; elastic reorientation of HB permanent dipoles; and rather free libration of permanent dipoles in 'defects' of water/ice structure. The suggested TV-dielectric relaxation mechanism allows us: (a) to remove the THz 'deficit' of loss epsilon" inherent in previous theoretical studies; (b) to explain the THz loss and absorption spectra in supercooled (SC) water; and (c) to describe, in agreement with the experiment, the low- and high-frequency tails of the two bands of ice H2O located in the range 10...300 cm(-1). Specific THz dielectric properties of SC water are ascribed to association of water molecules, revealed in our study by transverse vibration of HB charged molecules. (C) 2006 Published by Elsevier B.V.

Balancing deceit and disguise: How to successfully fool the defender in a 1 vs. 1 situation in rugby

Suddenly changing direction requires a whole body reorientation strategy. In sporting duels such as an attacker vs. a defender in rugby, successful body orientation/reorientation strategies are essential for successful performance. The aim of this study is to examine which biomechanical factors, while taking into account biomechanical constraints, are used by an attacker in a 1 vs. 1 duel in rugby. More specifically we wanted to examine how an attacker tries to deceive the defender yet disguise his intentions by comparing effective deceptive movements (DM+), ineffective deceptive movements (DM-), and non-deceptive movements (NDM). Eight French amateur expert rugby union players were asked to perform DMs and NDMs in a real 1 vs. 1 duel. For each type of movement (DM+, DM-, NDM) different relevant orientation/reorientation parameters, medio-lateral displacement of the center of mass (COM), foot, head, upper trunk, and lower trunk yaw; and upper trunk roll were analyzed and compared. Results showed that COM displacement and lower trunk yaw were minimized during DMs while foot displacement along with head and upper trunk yaw were exaggerated during DMs (DM+ and DM-). This would suggest that the player is using exaggerated body-related information to consciously deceive the defender into thinking he will run in a given direction while minimizing other postural control parameters to disguise a sudden change in posture necessary to modify final running direction. Further analysis of the efficacy of deceptive movements showed how the disguise and deceit strategies needed to be carefully balanced to successfully fool the defender. (C) 2010 Elsevier B.V. All rights reserved.

Detecting Deceptive Movement in 1 vs. 1 Based on Global Body Displacement of a Rugby Player

A key to success in many sports stems from the ability to anticipate what a player is going to do next. In sporting duels such as a 1 vs. 1 in rugby, the attacker can try and beat the defender by using deceptive movement. Those strategies involve an evolution of the centre of mass (COM) in the medio-lateral plane, from a minimal state to maximal displacement just before the final reorientation. The aim of this work is to consider this displacement as a motion-gap, as outlined in Tau theory, as a potential variable that may specify deceptive movement and as a means of comparing anticipatory performance between mid-level players and novices in rugby. Using a virtual reality set-up, 8 mid-level rugby players (ML) and 8 novices (NOV) observed deceptive (DM) and non-deceptive movements (NDM). The global framework used an occlusion time paradigm with four occlusion times. Participants had to judge the final direction of the attacker after the different cuts-off. For each movement and at each occlusion time, we coupled the ability to predict the good final direction with the value of the COM displacement in the medio-lateral (COM M/L) plane or with the Tau of this parameter (Tau COM). Firstly, results show that the Tau COM is a more predictive optical variable than the simple COM M/L. Secondly, this optical variable Tau COM is used by both groups, and finally, with a specific methodology we showed that mid-level players have significantly better anticipatory ability than the novice group.

A Case for Humanity in the Law of Rape.

One of Irigaray’s most insistent criticisms of the operation of patriarchal law is its overwhelming focus on the protection of property at the expense of law that regulates relations between and amongst persons. This paper argues, with reference to Irigaray’s work, that the conceptual change involved in such a reorientation of law’s focus has important implications for the legal perception of the harm of rape and woman’s sexuality. The possessive paradigm operates in the law of rape by disassociating the harm of rape from its psychic and subjective impact and encouraging the ‘simple’rape/ ‘real’ rape dichotomy. In returning subjectivity to woman herself we can begin to see perhaps how the crime of rape involves a harm to woman that affects the whole of her being, and to be. Such a reading allows the law to perhaps move away from understanding rape as a violation of undifferentiated bodies to a violation of the innate ‘virginity’ of woman.

Raymond Geuss’ radicalization of realism in political theory

Raymond Geuss has been viewed as one of the figureheads of the recent debates about realism in political theory. This interpretation, however, depends on a truncated understanding of his work of the past 30 years. I will offer the first sustained engagement with this work (in English and German) which allows understanding his realism as a project for reorienting political theory, particularly the relationship between political theory and politics. I interpret this reorientation as a radicalization of realismin political theory through the combination of the emphasis on the critical purpose of political theory and the provision of practical, contextual orientation. Their compatibility depends on Geuss’ understanding of criticism as negative, of power as ‘detoxified’ and of the critical purchase of political theory as based on the diagnostic engagement with its context. This radicalization particularly challenges the understanding of how political theory relates to its political context.

From Crisis to Opportunity: Turnaround Strategies of Large Irish Construction Contractors During the Period 2007-2015.

The sudden change in environmental munificence level in the construction sector
during the period 2007 – 2015 provides a natural experiment to investigate strategic
and operating actions of firms, particularly during an environmental jolt. Statistics on
business failures corroborate that neither academics nor practitioners have succeeded
in guiding strategic action during periods of environmental jolt. Despite the recent
increase of turnaround research in the general management domain, its use in the
construction management realm remains underexplored. To address this research
gap, five exploratory case studies of an ongoing PhD study were used to examine the
turnaround strategies of construction contractors during a period of economic
contraction and growth. The findings show that, although retrenchment is often
considered to be a short-term strategy, this is clearly not the case; with the majority of
contractors maintaining the strategy for 6-7 years. During the same period,
internationalization became critical, with the turnaround process shifting towards
strategic reorientation that altered the firms' market domain. The case studies further
suggest that strategic and operational actions resonate quite well with contemporary
practice-based approaches to strategy making. The findings provide valuable
assistance for construction contractors in dealing with organisational decline and in
developing a successful turnaround response.