Regulation of cell cycle and stress responses to hydrostatic pressure in fission yeast

We have investigated the cellular responses to hydrostatic pressure by using the fission yeast Schizosaccharomyces pombe as a model system. Exposure to sublethal levels of hydrostatic pressure resulted in G2 cell cycle delay. This delay resulted from Cdc2 tyrosine-15 (Y-15) phosphorylation, and it was abrogated by simultaneous disruption of the Cdc2 kinase regulators Cdc25 and Wee1. However, cell cycle delay was independent of the DNA damage, cytokinesis, and cell size checkpoints, suggesting a novel mechanism of Cdc2-Y15 phosphorylation in response to hydrostatic pressure. Spc1/Sty1 mitogen-activated protein (MAP) kinase, a conserved member of the eukaryotic stress-activated p38, mitogen-activated protein (MAP) kinase family, was rapidly activated after pressure stress, and it was required for cell cycle recovery under these conditions, in part through promoting polo kinase (Plo1) phosphorylation on serine 402. Moreover, the Spc1 MAP kinase pathway played a key role in maintaining cell viability under hydrostatic pressure stress through the bZip transcription factor, Atf1. Further analysis revealed that prestressing cells with heat increased barotolerance, suggesting adaptational cross-talk between these stress responses. These findings provide new insight into eukaryotic homeostasis after exposure to pressure stress.

The development of anxiety disorders in childhood: an integrative review

We present an integrative review of the development of child anxiety, drawing on a number of strands of research. Family aggregation and genetic studies indicate raised vulnerability to anxiety in offspring of adults with the disorder (e.g. the temperamental style of behavioural inhibition, or information processing biases). Environmental factors are also important; these include adverse life events and exposure to negative information or modelling. Parents are likely to be key, although not unique, sources of such influences, particularly if they are anxious themselves. Some parenting behaviours associated with child anxiety, such as overprotection, may be elicited by child characteristics, especially in the context of parental anxiety, and these may serve to maintain child disorder. Emerging evidence emphasizes the importance of taking the nature of child and parental anxiety into account, of constructing assessments and interventions that are both disorder specific, and of considering bidirectional influences.

Alignment of a model amyloid peptide fragment in bulk and at a solid surface

The alignment of model amyloid peptide YYKLVFFC is investigated in bulk and at a solid surface using a range of spectroscopic methods employing polarized radiation. The peptide is based on a core sequence of the amyloid beta (A beta) peptide, KLVFF. The attached tyrosine and cysteine units are exploited to yield information on alignment and possible formation of disulfide or dityrosine links. Polarized Raman spectroscopy on aligned stalks provides information on tyrosine orientation, which complements data from linear dichroism (LD) on aqueous solutions subjected to shear in a Couette cell. LD provides a detailed picture of alignment of peptide strands and aromatic residues and was also used to probe the kinetics of self-assembly. This suggests initial association of phenylalanine residues, followed by subsequent registry of strands and orientation of tyrosine residues. X-ray diffraction (XRD) data from aligned stalks is used to extract orientational order parameters from the 0.48 nm reflection in the cross-beta pattern, from which an orientational distribution function is obtained. X-ray diffraction on solutions subject to capillary flow confirmed orientation in situ at the level of the cross-beta pattern. The information on fibril and tyrosine orientation from polarized Raman spectroscopy is compared with results from NEXAFS experiments on samples prepared as films on silicon. This indicates fibrils are aligned parallel to the surface, with phenyl ring normals perpendicular to the surface. Possible disulfide bridging leading to peptide dimer formation was excluded by Raman spectroscopy, whereas dityrosine formation was probed by fluorescence experiments and was found not to occur except under alkaline conditions. Congo red binding was found not to influence the cross-beta XRD pattern.

Influence of the solvent on the self-assembly of a modified amyloid beta peptide fragment. II. NMR and computer simulation investigation

The conformation of a model peptide AAKLVFF based on a fragment of the amyloid beta peptide A beta 16-20, KLVFF, is investigated in methanol and water via solution NMR experiments and Molecular dynamics computer simulations. In previous work, we have shown that AAKLVFF forms peptide nanotubes in methanol and twisted fibrils in water. Chemical shift measurements were used to investigate the solubility of the peptide as a function of concentration in methanol and water. This enabled the determination of critical aggregation concentrations, The Solubility was lower in water. In dilute solution, diffusion coefficients revealed the presence of intermediate aggregates in concentrated solution, coexisting with NMR-silent larger aggregates, presumed to be beta-sheets. In water, diffusion coefficients did not change appreciably with concentration, indicating the presence mainly of monomers, coexisting with larger aggregates in more concentrated solution. Concentration-dependent chemical shift measurements indicated a folded conformation for the monomers/intermediate aggregates in dilute methanol, with unfolding at higher concentration. In water, an antiparallel arrangement of strands was indicated by certain ROESY peak correlations. The temperature-dependent solubility of AAKLVFF in methanol was well described by a van't Hoff analysis, providing a solubilization enthalpy and entropy. This pointed to the importance of solvophobic interactions in the self-assembly process. Molecular dynamics Simulations constrained by NOE values from NMR suggested disordered reverse turn structures for the monomer, with an antiparallel twisted conformation for dimers. To model the beta-sheet structures formed at higher concentration, possible model arrangements of strands into beta-sheets with parallel and antiparallel configurations and different stacking sequences were used as the basis for MD simulations; two particular arrangements of antiparallel beta-sheets were found to be stable, one being linear and twisted and the other twisted in two directions. These structures Were used to simulate Circular dichroism spectra. The roles of aromatic stacking interactions and charge transfer effects were also examined. Simulated spectra were found to be similar to those observed experimentally.(in water or methanol) which show a maximum at 215 or 218 nm due to pi-pi* interactions, when allowance is made for a 15-18 nm red-shift that may be due to light scattering effects.

Dynamic shear modulus of isotropic elastomers

We have investigated the dynamic mechanical behavior of two cross-linked polymer networks with very different topologies: one made of backbones randomly linked along their length; the other with fixed-length strands uniformly cross-linked at their ends. The samples were analyzed using oscillatory shear, at very small strains corresponding to the linear regime. This was carried out at a range of frequencies, and at temperatures ranging from the glass plateau, through the glass transition, and well into the rubbery region. Through the glass transition, the data obeyed the time-temperature superposition principle, and could be analyzed using WLF treatment. At higher temperatures, in the rubbery region, the storage modulus was found to deviate from this, taking a value that is independent of frequency. This value increased linearly with temperature, as expected for the entropic rubber elasticity, but with a substantial negative offset inconsistent with straightforward enthalpic effects. Conversely, the loss modulus continued to follow time-temperature superposition, decreasing with increasing temperature, and showing a power-law dependence on frequency.

A vector approach to the assessment of undergraduate engineering courses

In any undergraduate engineering programme there is a need to assess the balance and flavour of the various educational strands. In order for a quality assurance of these programmes to be met there is a need to evaluate the course load, academic content and the assessment marks of each course in the undergraduate programme. The existing ranges of QA methods for these programmes are focused on one or two of these issues and do not provide a comprehensive assessment procedure. Following a review of the existing QA methods, this paper will define a three-dimensional approach to the assessment of the educational aspects of an undergraduate course. Various features of this method will be described and potential benefits explained.

Reaction of a phospholipid monolayer with gas-phase ozone at the air-water interface: measurement of surface excess and surface pressure in real time

The reaction between gas-phase ozone and monolayers of the unsaturated lipid 1-palmitoy1-2-oleoyl-sn-glycero-3-phosphocholine, POPC, on aqueous solutions has been studied in real time using neutron reflection and surface pressure measurements. The reaction between ozone and lung surfactant, which contains POPC, leads to decreased pulmonary function, but little is known shout the changes that occur to the interfacial material as a result of oxidation. The results reveal that the initial reaction of ozone with POPC leads to a rapid increase in surface pressure followed by a slow decrease to very low values. The neutron reflection measurements, performed on an isotopologue of POPC with a selectively deuterated palmitoyl strand, reveal that the reaction leads to loss of this strand from the air-water interface. suggesting either solubilization of the product lipid or degradation of the palmitoyl strand by a reactive species. Reactions of H-1-POPC on D2O reveal that the headgroup region of the lipids in aqueous solution is not dramatically perturbed by the reaction of POPC monolayers with ozone supporting degradation of the palmitoyl strand rather than solubilization. The results are consistent with the reaction of ozone with the oleoyl strand of POPC at the air water interface leading to the formation of OH radicals. the highly reactive OH radicals produced can then go on to react with the saturated palmitoyl strands leading to the formation or oxidized lipids with shorter alkyl tails.

Television and the popular: viewing from the British perspective

The academic discipline of television studies has been constituted by the claim that television is worth studying because it is popular. Yet this claim has also entailed a need to defend the subject against the triviality that is associated with the television medium because of its very popularity. This article analyses the many attempts in the later twentieth and twenty-first centuries to constitute critical discourses about television as a popular medium. It focuses on how the theoretical currents of Television Studies emerged and changed in the UK, where a disciplinary identity for the subject was founded by borrowing from related disciplines, yet argued for the specificity of the medium as an object of criticism. Eschewing technological determinism, moral pathologization and sterile debates about television's supposed effects, UK writers such as Raymond Williams addressed television as an aspect of culture. Television theory in Britain has been part of, and also separate from, the disciplinary fields of media theory, literary theory and film theory. It has focused its attention on institutions, audio-visual texts, genres, authors and viewers according to the ways that research problems and theoretical inadequacies have emerged over time. But a consistent feature has been the problem of moving from a descriptive discourse to an analytical and evaluative one, and from studies of specific texts, moments and locations of television to larger theories. By discussing some historically significant critical work about television, the article considers how academic work has constructed relationships between the different kinds of objects of study. The article argues that a fundamental tension between descriptive and politically activist discourses has confused academic writing about ›the popular‹. Television study in Britain arose not to supply graduate professionals to the television industry, nor to perfect the instrumental techniques of allied sectors such as advertising and marketing, but to analyse and critique the medium's aesthetic forms and to evaluate its role in culture. Since television cannot be made by ›the people‹, the empowerment that discourses of television theory and analysis aimed for was focused on disseminating the tools for critique. Recent developments in factual entertainment television (in Britain and elsewhere) have greatly increased the visibility of ›the people‹ in programmes, notably in docusoaps, game shows and other participative formats. This has led to renewed debates about whether such ›popular‹ programmes appropriately represent ›the people‹ and how factual entertainment that is often despised relates to genres hitherto considered to be of high quality, such as scripted drama and socially-engaged documentary television. A further aspect of this problem of evaluation is how television globalisation has been addressed, and the example that the issue has crystallised around most is the reality TV contest Big Brother. Television theory has been largely based on studying the texts, institutions and audiences of television in the Anglophone world, and thus in specific geographical contexts. The transnational contexts of popular television have been addressed as spaces of contestation, for example between Americanisation and national or regional identities. Commentators have been ambivalent about whether the discipline's role is to celebrate or critique television, and whether to do so within a national, regional or global context. In the discourses of the television industry, ›popular television‹ is a quantitative and comparative measure, and because of the overlap between the programming with the largest audiences and the scheduling of established programme types at the times of day when the largest audiences are available, it has a strong relationship with genre. The measurement of audiences and the design of schedules are carried out in predominantly national contexts, but the article refers to programmes like Big Brother that have been broadcast transnationally, and programmes that have been extensively exported, to consider in what ways they too might be called popular. Strands of work in television studies have at different times attempted to diagnose what is at stake in the most popular programme types, such as reality TV, situation comedy and drama series. This has centred on questions of how aesthetic quality might be discriminated in television programmes, and how quality relates to popularity. The interaction of the designations ›popular‹ and ›quality‹ is exemplified in the ways that critical discourse has addressed US drama series that have been widely exported around the world, and the article shows how the two critical terms are both distinct and interrelated. In this context and in the article as a whole, the aim is not to arrive at a definitive meaning for ›the popular‹ inasmuch as it designates programmes or indeed the medium of television itself. Instead the aim is to show how, in historically and geographically contingent ways, these terms and ideas have been dynamically adopted and contested in order to address a multiple and changing object of analysis.

Construction of supramolecular helices and breaking the helicity by forming supramolecular β-sheet structures using suitable self-assembling pseudopeptide building blocks

Bis-valine derivatives or malonamide (Guha,S.; Drew, M.G.B. Small 2008, 4, 1993-2005) and a bis-valine derivative of 1,1-cyclopropone dicarboxamide were used as building blocks for the construction of supramolecular helical structures. The six-membered intramolecular hydrogen-bonded scaffold is formed, and this acts as a unique supramolecular synthon for the construction of a pseudopeptide-based supramolecular helical structure. However, in absence of this intramolecular hydrogen bond. intermolecular hydrogen bonds are formed among the peptide strands. This leads to a supramolecular beta-sheet structure. Proper selection of the supramolecular synthon (six-membered intramolecular hydrogenbonded scaffold) promotes supramolecular helix formation, and a deviation from this molecular structure dictates the disruption of supramolecular helicity. In this study, six crystal structures have been used to demonstrate that a change in the central angle and/or the central core structure of dicarboxamides can be used to design either a supramolecular helix or a beta-sheet.

Infrared linear dichroism spectroscopy on amyloid fibrils aligned by molecular combing

We report the use of molecular combing as an alignment method to obtain macroscopically oriented amyloid fibrils on planar surfaces. The aligned fibrils are studied by polarized infrared spectroscopy. This gives structural information that cannot be definitively obtained from standard infrared experiments on isotropic samples, for example, confirmation of the characteristic cross-beta amyloid core structure, the side-chain orientation from specific amino acids, and the arrangement of the strands within the fibrils, as we demonstrate here. We employed amyloid fibrils from hen egg white lysozyme (HEWL) and from a model octapeptide. Our results demonstrate molecular combing as a straightforward method to align amyloid fibrils, producing highly anisotropic infrared linear dichroism (IRLD) spectra.

Construction safety and digital design: a review

As digital technologies become widely used in designing buildings and infrastructure, questions arise about their impacts on construction safety. This review explores relationships between construction safety and digital design practices with the aim of fostering and directing further research. It surveys state-of-the-art research on databases, virtual reality, geographic information systems, 4D CAD, building information modeling and sensing technologies, finding various digital tools for addressing safety issues in the construction phase, but few tools to support design for construction safety. It also considers a literature on safety critical, digital and design practices that raises a general concern about ‘mindlessness’ in the use of technologies, and has implications for the emerging research agenda around construction safety and digital design. Bringing these strands of literature together suggests new kinds of interventions, such as the development of tools and processes for using digital models to promote mindfulness through multi-party collaboration on safety

A metaphorical analysis of client organisations and the briefing process

This paper reviews and critiques the current practice of classifying building clients according to their 'type'. An alternative approach to understanding organisations is developed in accordance with the principles of naturalistic inquiry. It is contended that the complex pluralistic clients of the 1990s can only really be understood 'from the inside'. The concept of organisational metaphors is introduced as the basis for a more sophisticated way of thinking about organisations. The various strands of organisational theory are also analyzed in terms of their underlying metaphors. Different theories are seen to bring different insights. The implicit metaphors adopted by practitioners are held to be important in that they tend to dictate the adopted approach to client briefing. This contention is illustrated by analyzing three different characterisations of the briefing process in terms of their underlying metaphors. Finally, the discussion is placed in a contemporary UK context by comparing the dominant paradigm of practice during the 1980s to that of the 1990s.

Sleepwalking from New York to Miami

In the winter of 2007, Doug Aitken’s moving image installation, sleepwalkers, was projected onto the exterior walls of the Museum of Modern Art in New York. The project was a collaboration between Aitken, the museum and Creative Time, a New York-based organisation that commissions public art projects. A site-specific version of the installation has been commissioned by the Miami Art Museum for the opening of its new facility, designed by Swiss architects Herzog and de Meuron, in 2013: “sleepwalkers (Miami) will expand the work’s landscape and characters in a manner that reflects the diverse social fabric of Miami.” This essay examines sleepwalkers as an example of the emerging form of film as public art. There are three strands to my argument: first, an examination of the role of film in the redefinition of public art, shifting away from spatial practices concerned with fixed and permanent notions of space, community and art and towards transient and experimental spatial and artistic practices; second,a discussion of the relationship between projection and the built environment and the ways that the qualities of luminescence, transparency, movement and connectivity are transferred from projected images to the surfaces on which they are projected and the spaces around them; and third, an examination of the ways that sleepwalkers uses only certain aspects of narrativity, those concerned with movement and change, and avoids hermeneutic absorption in order to keep the spectators moving (transposing the idea of sleepwalking from characters to spectators). Transience and transparency are key ideas in the conceptualisation of the work, and these are deployed with significant differences in relation to the distinctive characteristics of each city and each museum.

Commercial property loan valuations in the UK : the changing landscape of practice and liability

This paper is the first of two which aim to examine the major legal liability implications of changes to the commercial property loan valuation process caused by the recession in the UK property market and to make recommendations to valuers and their professional institutions to improve the quality of the process and the result. This paper identifies the market background to commercial property lending and discusses the implications of the falls in value for lenders and valuers. These include two major strands; first, the outcome of discussions between the representative bodies of these two groups and, second, the increasing litigation caused by lenders suing valuers for professional negligence. The discussions between representative groups have driven a debate on the valuation process leading to a number of reports and guidance notes. This paper discusses the outcomes paying particular attention to the basis of valuation for loan purposes and the provision of additional information in valuation reports. This paper also reviews the legal framework which influences the relationship between the lenders and valuers and discusses the duty of care. The role of instructions in the valuation process, the significance of the identity of the person to be advised and the possibility of a conflict of interest arising are all considered. The paper also addresses the issue of the standards required of a commercial loan valuer, including how this is interpreted by the courts and the legal status of professional guidance notes. The paper concludes by identifying potential areas for dispute within the loan valuation process and raising a number of research questions concerning the operation of this process which are addressed in a following paper.

Synthesis of 3 '-S-phosphorothiolate oligonucleotides for their potential use in RNA interference

The potency of RNA interference (RNAi) undoubtedly can be improved through chemical modifications to the small interfering RNAs (siRNA). By incorporation of the 3′-S-phosphorothiolate modification into strands of RNA, it is hoped that specific regions of a siRNA duplex can be stabilised to enhance the target binding affinity of a selected antisense strand into the activated RNA-induced silencing complex (RISC*). Oligonucleotides composed entirely of this modification are desirable so unconventional 5′ → 3′ synthesis is investigated, with initial solution-phase testing proving successful. The phosphoroamidite monomer required for solid-phase synthesis has also been produced.