30 research outputs found
Anomalous mode, elastic constants and phonon images in CaWO4
No full textStimulated by the “anomalous mode” observed in the time-of-flight measurement of phonon signals [J.K. Wigmore, A.G. Kozorezov, H. bin Rani, M. Giltrow, H. Kraus, B.M. Taele, Physica B 316–317 (2002) 589], we have theoretically studied the group velocities and the phonon images in CaWO4. Comparing the phonon caustics of transverse modes in the low-frequency nondispersive and slightly dispersive 1 THz regions, we propose that the anomalous phonon mode is originated from the phonons near the cuspidal edge of the group velocity curve of the fast transverse branch. Also the low-frequency phonon images (two-dimensional maps of phonon group velocities) calculated from the two sets of published elastic-constant data of CaWO4 [J.M. Farley, G.A. Saunders, J. Phys. C: Solid State Phys. 5 (1972) 3021] and [M. Gluyas, F.D. Hughes, B.M. James, J. Phys. D: Appl. Phys. 6 (1973) 2025] are compared. A significant difference is found in the images in the X–Y plane owing to the variance of the reported values of C13 of about 40%
Pharmaceuticals in the aquatic environment: β-blockers as a case study
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 20/09/2008.The presence of many human pharmaceuticals in the aquatic environment is now a worldwide concern and yet little is known of the chronic effects that these bioactive substances may be having on aquatic organisms. This study used mammalian pharmacodynamics to predict the mode of action of the 13-blocker, propranolol, on fish, in order to identify chronic effects in fathead minnows. β-blockers target β1- and β2-adrenergic receptors in humans and hence these receptors were characterised in the fathead minnow. It was found that fish possess β1- and β2-ARs that are structurally very similar to their mammalian counterparts. Further, the distributions of these two β-ARs in various organs of the fathead minnow were similar to those in mammals. Pair-breeding assays were conducted, in which fathead minnows were exposed to various concentrations of propranolol. To discover whether β-ARs had been up or down regulated by propranolol, molecular analysis was conducted on different tissues of the exposed fish using real-time polymerase-chain reactions (RT-PCR). Exposure of fathead minnows to propranolol caused acute toxicity at 10 mg/L. Propranolol caused a statistically significant decrease in reproduction at 1.0 mg/L, dose-related decreases in male weight, condition index and fatpad weight, and a dose-related increase in female GSI. Molecular analysis of βl- and β2-AR expression levels revealed a dose-related decrease in β2-AR expression in fathead liver and heart. LOEC and NOEC values were 0.1 mg/L and 0.01 mg/L, respectively. Propranolol plasma concentrations in fish exposed to water concentrations of 0.1 and 1.0 mg/L were greater than the human therapeutic concentration and hence these data very strongly support the fish plasma model proposed by Huggett et al. (2001).European Union (as part of the ERAPharm consortium
Phonon study of vertical resonant structures
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN009977 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Pharmaceuticals in the aquatic environment : β-blockers as a case study
No full textThe presence of many human pharmaceuticals in the aquatic environment is now a worldwide concern and yet little is known of the chronic effects that these bioactive substances may be having on aquatic organisms. This study used mammalian pharmacodynamics to predict the mode of action of the 13-blocker, propranolol, on fish, in order to identify chronic effects in fathead minnows. β-blockers target β1- and β2-adrenergic receptors in humans and hence these receptors were characterised in the fathead minnow. It was found that fish possess β1- and β2-ARs that are structurally very similar to their mammalian counterparts. Further, the distributions of these two β-ARs in various organs of the fathead minnow were similar to those in mammals. Pair-breeding assays were conducted, in which fathead minnows were exposed to various concentrations of propranolol. To discover whether β-ARs had been up or down regulated by propranolol, molecular analysis was conducted on different tissues of the exposed fish using real-time polymerase-chain reactions (RT-PCR). Exposure of fathead minnows to propranolol caused acute toxicity at 10 mg/L. Propranolol caused a statistically significant decrease in reproduction at 1.0 mg/L, dose-related decreases in male weight, condition index and fatpad weight, and a dose-related increase in female GSI. Molecular analysis of βl- and β2-AR expression levels revealed a dose-related decrease in β2-AR expression in fathead liver and heart. LOEC and NOEC values were 0.1 mg/L and 0.01 mg/L, respectively. Propranolol plasma concentrations in fish exposed to water concentrations of 0.1 and 1.0 mg/L were greater than the human therapeutic concentration and hence these data very strongly support the fish plasma model proposed by Huggett et al. (2001).EThOS - Electronic Theses Online ServiceEuropean Union (as part of the ERAPharm consortium)GBUnited Kingdo
Investigating Blawgs through corpus linguistics : issues of generic integrity
No full textToday research in linguistics and discourse analysis is increasingly turning its attention to web-mediated communication, looking at genres which – whether they be derived from migration of traditional genres to the web, or generated anew in the Hypermedia Computer-Mediated Environment (Hoffman/Novak 1996) – exhibit properties that are peculiar to this environment (e.g. hypertextuality, dispersion across different layers of the hypertext, configuration in lexias, etc.), making them at least partially different from traditional printed texts. Hence the question of whether the repertoire of analytical tools developed for the latter is suitable for use in the analysis of web-mediated genres.
This question has been posed in various methodological perspectives (i.e. text linguistics: e.g. Garzone 2002; genre analysis: e.g. Askehave/Ellerup Nielsen 2005, Garzone 2007; Giltrow/Stein 2009; Santini/Meheler/Sharoff 2010; argumentation theory: Carter 2000; Lewiński 2010; Degano 2012, etc.)
This chapter focuses on the weblog, a relatively ‘young’ web-mediated genre, which has traditionally been seen as characterised by three main constitutive features – the reverse chronology of its entries, the frequent updating, and the combination of links with personal commentary (cf. e.g. Miller/Shepherd 2004: 4; Herring/Kouper et al. 2005: 1) – and by a typically individualistic existential dimension, having originated as a form of communication especially suitable for self expression (Herring/Scheidt et al. 2005; Miller/Shepherd 2004, 2009; Garzone 2012). Another recurrent peculiarity of the blog is that in most cases it consists of two different text formats, posts and comments, which are communicatively heterogeneous and have different characteristics.
This chapter uses corpus linguistics to investigate the genre of the weblog, starting with a discussion of the criteria to be applied in the construction of a corpus of texts belonging to this genre, in consideration of its distinctive characteristics, first and foremost the presence of comments in addition to posts.
In particular, the analysis focuses on the so called ‘blawgs’, i.e. blogs used for the dissemination of legal knowledge and for debate in the field of the law. This is one of a diversified range of textual forms in specialised and professional communication into which blogs have evolved, largely losing their original individualistic dimension. Blawgs are quite numerous today being used for various different purposes, e.g. academic and professional duties, forms of scholarship, scholarly conversations and exchanges, instant academic publication (Berman 2006, 2007; Kerr 2006; Solum 2006; Volokh 2006). They also represent a genre that enables writers in this area of specialization to reach much larger audiences than those traditionally addressed.
The main purpose of this chapter is to explore the distinctive features of the blawg as a genre in order to verify the degree to which it has changed evolving from a personal, diary-like format at the intersection between private and public (Miller/Shepherd 2004) into a form of academic, professional or journalistic expression, and whether this evolution has been so extensive as to jeopardise its generic integrity. A further aim is to assess the degree of variation within the genre, considering different types of law blogs.
The corpus on which this study is based comprises texts from five legal blogs, three from the UK and two from the US, and is examined on the basis of textual evidence retrieved by means of computerized analysis, using Wordsmith Tools 5.0 (Scott 2011). The traits considered are part of the core generic features of the blawg, with special attention for indicators that are associated with the personal/existential component, and in particular self-mention (Hyland 2001), as well as the lexical verbs associated with it, especially metadiscursive and narrative verbs. Some other elements of metadiscourse are also examined as providing evidence of a strong personal authorial presence, in keeping with the originally personal and individualistic character of the genre. In order to identify the peculiarities of the texts analysed within the more general picture of legal communication, the data obtained from the blawg corpus are compared with data relative to other types of (meta)legal texts: research papers included in the law section of the CADIS corpus (courtesy of University of Bergamo, group coordinated by M. Gotti), and with awards from Kluwer Bank, issued from 1998 to 2002.
In addition to the literature on web communication referred to above, the specific analytical toolkit deployed in this research includes studies on blogs from various disciplinary perspectives (e.g. Blood 2002; Herring/Kouper et al. 2005; Herring & Paolillo 2006; Puschmann 2007; Giltrow/Stein eds 2009; Myers 2009; Grieve/Biber et al. 2010) as well as studies of law blogs, mainly by legal scholars (e.g. Caron 2006; Kerr 2006).
References
Askehave, Inger / Ellerup Nielsen, Anne 2004. Webmediated Genres – A Challenge to Traditional Genre Theory. Working Paper nr. 6. Aarhus: Center for Virksomhedskommunication.
Berman, D. 2007. More grist for the blog-scholarship debate [Blog post]. Sentencing Law and Policy, March 19, 2007. http://sentencing.typepad.com/sentencing_law_and_policy/2007/03/more_grist_ for_.html.
Berman, D. A. (2006). Scholarship in action: The power, possibilities and pitfalls for law professor blogs. Public Law and Legal Theory Working Series n. 6, Center for Interdisciplinary Law and Policy Studies, the Ohio State University Mortz College of Law, http://ssrn.com/abstract=898174.
Blood, Rebecca 2002. Weblogs: A History and Perspective. In We’ve Got Blog. How Weblogs are Changing our Culture. Cambridge, MA. Perseus, 7-16. Caron, Paul L. 2006, Are Scholars Better Bloggers? Bloggership: How Blogs are Transforming Legal Scholarship. Washington University Law Review, 84/5: 1025-1042.
Caron, Paul L. 2006. Are Scholars Better Bloggers? Bloggership: How Blogs are Transforming Legal Scholarship. Washington University Law Review, 84/5: 1025-1042.
Carter, Locke M. 2003. Argument in hypertext: Writing strategies and the problem of order in a nonsequential world. Computers and Composition. 20, 3-22.
Degano, Chiara 2012. Argumentative Genres on the Web: The Case of Two NGOs’ Campaigns. In Campagna, Sandra / Garzone, Giuliana (eds) Evolving Genres in Web-mediated Communication. Bern: Peter Lang, 99-129.
Garzone G. 2012. Where Do Web Genres Come from? The Case of Blogs. In Campagna, Sandra / Garzone, Giuliana (eds) Evolving Genres in Web-mediated Communication. Bern: Peter Lang, 227-253.
Garzone, Giuliana 2002. Describing E-commerce Communication. Which Models and Categories for Text Analysis?. In Evangelisti, Paola / Ventola, Eija (eds). TEXTUS (English in Academic and Professional Settings). 14/2, 279-296.
Garzone, Giuliana 2007. Genres, Multimodality and the World-Wide Web: Theoretical Issues. In Garzone / Catenaccio / Poncini (eds), 15-30.
Giltrow, Janet / Stein, Dieter 2009. Genres in the Internet. Innovation, Evolution and Genre Theory. In Giltrow, Janet / Stein, Dieter (eds) Genres in the Internet: Issues on the Theory of Genres. Amsterdam: John Benjamins, 1-25.
Grieve, Jack / Biber, Douglas / Friginal, Eric / Nekrasova, Tatiana 2010. Variations Among Blogs: A Multi-dimensional Analysis. In Mehler, Alexander / Sharoff, Serge/ Santini, Marina. Genres on the Web: Computational Models and Empirical Studies 1st ed. New York: Springer, 303-322.
Henninger, Daniel 2006. When Blogs Rule. We’ll All Talk Like --- Wall Street Journal, April 21, 2006, A17.
Herring, Susan / Paolillo, John C. 2006. Gender and Genre Variation in Weblogs. Journal of Sociolinguistics 10/4, 439-459.
Herring, Susan C. / Kouper, Inna / Paolillo, John C. / Scheidt, Lois Ann / Tyworth, Michael / Welsch, Peter / Wright, Elijah / Yu, Ning 2005. Conversations in the Blogosphere: An Analysis ‘From the Bottom Up’. Proceedings of the 38th Hawaii International Conference on System Sciences. IEEE.
Herring, Susan C. / Scheidt, Lois Ann / Wright, Elijah / Bonus. Sabrina 2005. Weblogs as a bridging genre. Information Technology & People 18/2, 142-171.
Hoffman, Donna L. / Novak, Thomas P. 1996. Marketing in Hypermedia Computer-Mediated Environments: Conceptual Foundations. Journal of Marketing. 60(July), 50-68.
Hyland, Ken 2001. Humble Servants of the Discipline? Self-mention in Research Articles. English for Specific Purposes. 20/3, 207-226.
Hyland, Ken 2005. Metadiscourse. Exploring Interaction in Writing. London: Continuum.
Kerr, Orin S. 2006. Blogs and the Legal Academy, George Washington University Public Law and Legal Theory Working Paper No. 203, Available at http://papers.ssrn.com/sol3/cf_dev/AbsByAuth.cfm?per _id=328150, accessed 1 October 2012.
Lewiński, Marcin. 2010. Internet political discussion forums as an argumentative activity type. A pragma-dialectical analysis of online forms of strategic manoeuvring in reacting critically. Amsterdam: SicSat. Available online: at , accessed 1 October 2012.
Miller, Carolyn R. / Shepherd, Dawn 2004. Blogging as Social Action: A Genre Analysis of the Weblog. In Gurak, Laura et al. (eds) Into the Blogosphere: Rhetoric, Community, and Culture of Weblogs. , retrieved 04/08/2010.
Miller, Carolyn R. / Shepherd, Dawn 2009. Questions for Genre Theory from the Blogosphere. In Giltrow, Janet / Stein, Dieter (eds) Genres in the Internet: Issues on the Theory of Genres. Amsterdam: John Benjamins, 263-290.
Myers, Greg 2009. The Discourse of Blogs and Wikis. London: Continuum.
Puschmann, Cornelius 2009. Lies at Wal-Mart. Style and the Subversion of Genre in the Life at Wal-Mart blog. In Giltrow, Janet / Stein, Dieter (eds) Genres in the Internet: Issues on the Theory of Genres. Amsterdam: John Benjamins, 49-84.
Santini, Marina / Mehler, Alexander/ Sharoff, Serge. 2010. Riding the Rough Waves of Genre on the Web. In Mehler, Alexander/ Sharoff, Serge/ Santini, Marina. Genres on the Web: Computational Models and Empirical Studies.
Scott, Mike 2011. Wordsmith Tools 5.0. Oxford: Oxford University Press.
Solum, Lawrence B. 2006. Blogging and the transformation of legal scholarship. Paper presented at Bloggership: How blogs are transforming legal scholarship, http://ssrn.com/paper=898168
Volokh, Eugene 2006. Scholarship, blogging and trade-offs: On discovering, disseminating and doing. Paper presented at Bloggership: How blogs are transforming legal scholarship. Washington University Law Review, 84/5, 1089-110. Available at: http://digitalcommons.law.wustl.edu/lawreview/ vol84/iss5/
Mutual interactions between objects oscillating in isotopically pure superfluid ⁴He in the T → 0 limit
No full textWe report the results of experiments to explore interactions between physically separated oscillating objects
in isotopically pure superfluid ⁴He at T ∼ 10 mK. The investigations focused mainly on 32 kHz quartz tuning
forks, but also consider a nearby 1 kHz oscillating grid. The low-drive linewidth (LDL) and resonant frequency
fd of a detector fork were monitored while the maximum velocity of a transmitter fork, separated from the detector
by a few mm, was varied over a wide range. Clear evidence was found for mutual interactions between the
two forks, and for the influence of the grid on the forks. Monitoring the detector's LDL and fd provides evidence
for a generator critical velocity in the range 0.3 < vc₁ <1.0 cm/s for onset of the detector responses, in addition to
a second critical velocity vc₂ ∼ 13 cm/s probably corresponding to the production of quantum turbulence at the
generator. The results are discussed, but are not yet fully understood.We gratefully acknowledge many valuable discussions
with W.F. Vinen. The investigations were supported by the
Engineering and Physical Sciences Research Council (UK)
and the Russian Academy of Sciences programme “Quantum
mesoscopic disordered systems”
Mutual interactions between objects oscillating in isotopically pure superfluid ⁴He in the T → 0 limit
No full textWe report the results of experiments to explore interactions between physically separated oscillating objects
in isotopically pure superfluid ⁴He at T ∼ 10 mK. The investigations focused mainly on 32 kHz quartz tuning
forks, but also consider a nearby 1 kHz oscillating grid. The low-drive linewidth (LDL) and resonant frequency
fd of a detector fork were monitored while the maximum velocity of a transmitter fork, separated from the detector
by a few mm, was varied over a wide range. Clear evidence was found for mutual interactions between the
two forks, and for the influence of the grid on the forks. Monitoring the detector's LDL and fd provides evidence
for a generator critical velocity in the range 0.3 < vc₁ <1.0 cm/s for onset of the detector responses, in addition to
a second critical velocity vc₂ ∼ 13 cm/s probably corresponding to the production of quantum turbulence at the
generator. The results are discussed, but are not yet fully understood.We gratefully acknowledge many valuable discussions
with W.F. Vinen. The investigations were supported by the
Engineering and Physical Sciences Research Council (UK)
and the Russian Academy of Sciences programme “Quantum
mesoscopic disordered systems”
Experiments on a high quality grid oscillating in superfluid 4He at very low temperatures.
No full textWe have investigated a copper-mesh grid oscillating at its fundamental (0, 1) Bessel mode in superfluid 4He for temperatures 10< T <1500 mK at a pressure of P = 5 bar. The high quality factor (Q ∼ 10 to power 5) of the oscillator allowed us to observe new features of its response to a periodic drive which, at the lowest T, was found to depend on the prehistory of the helium. The experiments have confirmed the existence of two critical velocities, and we discuss whether these critical velocities are associated with quantized vortices
Behavior of quartz forks oscillating in isotopically pure He-4 in the T -> 0 limit
No full textWe report that at low drives, the resonant frequencies and linewidths of nominally 32-kHz quartz tuning forks oscillating in isotopically pure superfluid He-4 at similar to 10 mK are dependent on the dimensions of their environment. We confirm the importance of coupling between forks and acoustic modes within the cell, and develop a theory of their coupled dynamics to account for the observations. The frequencies and linewidths are reproducible on a time scale of tens of minutes, but pronounced drifts are seen over longer intervals. We suggest that the drifts are attributable to changes in the velocity of sound due to tiny pressure changes. In studies at high drives, we observe two critical velocities: v(c1) approximate to 0.6 cm/s, where the drag may either increase or decrease, depending on the linewidth; and v(c2) approximate to 10 cm/s, above which there seems to be fully turbulent flow. At high drives, the behavior of the drag differs markedly between forks that appear otherwise to be very similar
