246 research outputs found
Centre-of-mass separation in quantum mechanics: Implications for the many-body treatment in quantum chemistry and solid state physics
We address the question to what extent the centre-of-mass (COM) separation
can change our view of the many-body problem in quantum chemistry and solid
state physics. It was shown that the many-body treatment based on the
electron-vibrational Hamiltonian is fundamentally inconsistent with the
Born-Handy ansatz so that such a treatment can never respect the COM problem.
Born-Oppenheimer (B-O) approximation reveals some secret: it is a limit case
where the degrees of freedom can be treated in a classical way. Beyond the B-O
approximation they are inseparable in principle. The unique covariant
description of all equations with respect to individual degrees of freedom
leads to new types of interaction: besides the known vibronic (electron-phonon)
one the rotonic (electron-roton) and translonic (electron-translon)
interactions arise. We have proved that due to the COM problem only the
hypervibrations (hyperphonons, i.e. phonons + rotons + translons) have true
physical meaning in molecules and crystals; nevertheless, the use of pure
vibrations (phonons) is justified only in the adiabatic systems. This fact
calls for the total revision of our contemporary knowledge of all non-adiabatic
effects, especially the Jahn-Teller effect and superconductivity. The vibronic
coupling is responsible only for removing of electron (quasi)degeneracies but
for the explanation of symmetry breaking and forming of structure the rotonic
and translonic coupling is necessary.Comment: 39 pages, 11 sections, 3 appendice
Everyday cosmopolitanism in representations of Europe among young Romanians in Britain
The paper presents an analysis of everyday cosmopolitanism in constructions of Europe among young Romanian nationals living in Britain. Adopting a social representations approach, cosmopolitanism is understood as a cultural symbolic resource that is part of everyday knowledge. Through a discursively-oriented analysis of focus group data, we explore the ways in which notions of cosmopolitanism intersect with images of Europeanness in the accounts of participants. We show that, for our participants, representations of Europe are anchored in an Orientalist schema of West-vs.-East, whereby the West is seen as epitomising European values of modernity and progress, while the East is seen as backward and traditional. Our findings further show that representations of cosmopolitanism reinforce this East/West dichotomy, within a discourse of âOccidental cosmopolitanismâ. The paper concludes with a critical discussion of the diverse and complex ideological foundations of these constructions of European cosmopolitanism and their implications
Standard of civilization, nomadism and territoriality in nineteenth-century international society
In this chapter, the encounter between the Russian Empire and the nomads of the Eurasian steppe in the nineteenth century is analyzed using the theoretical framework of the standard of civilization. The creation of the Westphalian state-model in Europe in the seventeenth century, linked to the later emergence of the notion of the standard of civilization led to the âotheringâ of the nomads of the Eurasian steppe as barbarians, as a threat to the borders of civilized Europe. The chapter presents also an argument to define âterritorialityâ as not only an institution of international society of the time but also as a distinctive quality and requirement for being considered âcivilizedâ. In this analytical framework, the nomads become the âotherâ, the âalienâ, the âmenaceâ, onto which projections of rationality and modernity were cast in order to prevent threats to Russiaâs European and civilized identity. The chapter sheds light on the encounter between âfixedâ and âmobileâ units in the course of expansion of international society; contextualizes the role played by nomadic tribes in resisting the application of Westphalian spatial categories in the Eurasian space; and scrutinizes what the role of nomads was in constructing a European, civilized identity.PostprintPeer reviewe
Binary AMD Circuits from Secure Multiparty Computation
An AMD circuit over a finite field is a randomized arithmetic circuit that offers the ``best possible protection\u27\u27 against additive attacks. That is, the effect of every additive attack that may blindly add a (possibly different) element of to every internal wire of the circuit can be simulated by an ideal attack that applies only to the inputs and outputs.
Genkin et al. (STOC 2014, Crypto 2015) introduced AMD circuits as a means for protecting MPC protocols against active attacks, and showed that every arithmetic circuit C over F can be transformed into an equivalent AMD circuit of size with simulation error. However, for the case of the binary field , their constructions relied on a tamper-proof output decoder and could only realize a weaker notion of security.
We obtain the first constructions of fully secure binary AMD circuits. Given a boolean circuit and a statistical security parameter , we construct an equivalent binary AMD circuit of size (ignoring lower order additive terms) with simulation error. That is, the effect of toggling an arbitrary subset of wires can be simulated by toggling only input and output wires.
Our construction combines in a general way two types of ``simple\u27\u27 honest-majority MPC protocols: protocols that only offer security against passive adversaries, and protocols that only offer correctness against active adversaries. As a corollary, we get a conceptually new technique for constructing active-secure two-party protocols in the OT-hybrid model, and reduce the open question of obtaining such protocols with constant computational overhead to a similar question in these simpler MPC models
Nebuliser therapy in the intensive care unit
The relationship between identity, lived experience, sexual practices and the language through which these are conveyed has been widely debated in sexuality literature. For example, âcoming outâ has famously been conceptualised as a âspeech actâ (Sedgwick 1990) and as a collective narrative (Plummer 1995), while a growing concern for individualsâ diverse identifications in relations to their sexual and gender practices has produced interesting research focusing on linguistic practices among LGBT-identified individuals (Leap 1995; Kulick 2000; Cameron and Kulick 2006; Farqhar 2000). While an explicit focus on language remains marginal to literature on sexualities (Kulick 2000), issue of language use and translation are seldom explicitly addressed in the growing literature on intersectionality. Yet intersectional perspectives âreject the separability of analytical and identity categoriesâ (McCall 2005:1771), and therefore have an implicit stake in the âvernacularâ language of the researched, in the âscientificâ language of the researcher and in the relationship of continuity between the two. Drawing on literature within gay and lesbian/queer studies and cross-cultural studies, this chapter revisits debates on sexuality, language and intersectionality. I argue for the importance of giving careful consideration to the language we choose to use as researchers to collectively define the people whose experiences we try to capture. I also propose that language itself can be investigated as a productive way to foreground how individual and collective identifications are discursively constructed, and to unpack the diversity of lived experience. I address intersectional complexity as a methodological issue, where methodology is understood not only as the methods and practicalities of doing research, but more broadly as âa coherent set of ideas about the philosophy, methods and data that underlie the research process and the production of knowledgeâ (McCall 2005:1774). My points are illustrated with examples drawn from my ethnographic study on âlesbianâ identity in urban Russia, interspersed with insights from existing literature. In particular, I aim to show that an explicit focus on language can be a productive way to explore the intersections between the global, the national and the local in cross-cultural research on sexuality, while also addressing issues of positionality and accountability to the communities researched
The global politics of a âponcy pillowcaseâ: Migration and borders in Coronation Street
This article examines the ways in which popular culture stages and supplies resources for agency in everyday life, with particular attention to migration and borders. Drawing upon cultural studies, and specific insights originating from the Birmingham Centre for Contemporary Cultural Studies, we explore how intersectional identities such as race, ethnicity, class, and gender are experienced in relation to the globalisation of culture and identity in a 2007 Coronation Street storyline. The soap opera genre offers particular insights into how agency emerges in everyday life as migrants and locals navigate the forces of globalisation. We argue that a focus on popular culture can mitigate the problem of isolating migrant experiences from local experiences in migrant-receiving areas
Interleukin 15 Levels in Serum May Predict a Severe Disease Course in Patients with Early Arthritis
Background: Interleukin-15 (IL-15) is thought to be involved in the physiopathological mechanisms of RA and it can be detected in the serum and the synovial fluid of inflamed joints in patients with RA but not in patients with osteoarthritis or other inflammatory joint diseases. Therefore, the objective of this work is to analyse whether serum IL-15 (sIL-15) levels serve as a biomarker of disease severity in patients with early arthritis (EA). Methodology and Results: Data from 190 patients in an EA register were analysed (77.2% female; median age 53 years; 6-month median disease duration at entry). Clinical and treatment information was recorded systematically, especially the prescription of disease modifying anti-rheumatic drugs. Two multivariate longitudinal analyses were performed with different dependent variables: 1) DAS28 and 2) a variable reflecting intensive treatment. Both included sIL-15 as predictive variable and other variables associated with disease severity, including rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPA). Of the 171 patients (638 visits analysed) completing the follow-up, 71% suffered rheumatoid arthritis and 29% were considered as undifferentiated arthritis. Elevated sIL-15 was detected in 29% of this population and this biomarker did not overlap extensively with RF or ACPA. High sIL-15 levels (ÎČ Coefficient [95% confidence interval]: 0.12 [0.06-0.18]; p&0.001) or ACPA (0.34 [0.01-0.67]; p = 0.044) were significantly and independently associated with a higher DAS28 during follow-up, after adjusting for confounding variables such as gender, age and treatment. In addition, those patients with elevated sIL-15 had a significantly higher risk of receiving intensive treatment (RR 1.78, 95% confidence interval 1.18-2.7; p = 0.007). Conclusions: Patients with EA displaying high baseline sIL-15 suffered a more severe disease and received more intensive treatment. Thus, sIL-15 may be a biomarker for patients that are candidates for early and more intensive treatmentThe work of Belen DĂaz-SĂĄnchez was supported by the RETICS Programme (Programa de Redes TemĂĄticas de InvestigaciĂłn Colaborativa [Colaborative Research Thematic Network Programme]; RD08/0075 - RIER [Red de InflamaciĂłn y Enfermedades ReumĂĄticas; Inflammation and Rheumatic Diseases Network]) from the Instituto de Salud Carlos III, Spain (URL: www.isciii.es) within the VI National Plan for I+D+I 2008â2011 (FEDER). The work of Isidoro GonzĂĄlez-Ălvaro was in part supported by a grant for the Intensification of the Research Tasks in the National Health Care System from Instituto de Salud Carlos III, Spain. The consumables for measurements and data analysis were supported by a Fondo de InvestigaciĂłn Sanitaria grant (08/0754) from the Instituto de Salud Carlos II
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A pragmatic methodology for studying international practices
Practice turn marks an important advancement in International Relations theorizing. In challenging abstract meta-theoretical debates, practice theorizing in International Relations aims to get close to the lifeworld(s) of the actual practitioners of politics. Scholars from different positions such as constructivism, critical theory, and post-structuralism have critically interrogated the analytical framework of practices in international politics. Building upon these works, we are concerned with a question of how to examine the context of international practices that unfolds in multiple ways in practitionersâ performances. Our central thesis is that a distinct pragmatic methodology offers an opportunity to keep with the practice turn and avoid the problematic foundational moves of mainstream practice theorizing. This involves foregrounding three interrelated processes in examining practices: the role of exceptions in the normal stream of performances, normative uptake of the analysts, and the semantic field that actors navigate in political performances. We argue that this methodology is predicated on its usefulness to interpret practices through reflective social-science inquiry
A critical review of smaller state diplomacy
In The Peloponnesian War, Thucydides (1972: 402) highlights the effects of the general, overall
weakness of smaller states vis-Ă -vis larger, more powerful ones in a key passage, where the
Athenians remind the Melians that:
â⊠since you know as well as we do that, as the world goes, right is only in question
between equals in power. Meanwhile, the strong do what they can and the weak suffer
what they must.â
Concerns about the vulnerability of small, weak, isolated states have echoed throughout history:
from Thucydides, through the review by Machiavelli (1985) of the risks of inviting great powers
to intervene in domestic affairs, through 20th century US-led contemporary political science
(Vital, 1971; Handel, 1990) and Commonwealth led scholarship (Commonwealth Secretariat,
1985). In the context of 20th century âBalkanizationâ, the small state could also prove unstable,
even hostile and uncooperative, a situation tempting enough to invite the intrusion of more
powerful neighbours: a combination, according to Brzezinski (1997: 123-124) of a power
vacuum and a corollary power suction2: in the outcome, if the small state is âabsorbedâ, it would
be its fault, and its destiny, in the grand scheme of things. In an excellent review of small states
in the context of the global politics of development, Payne (2004: 623, 634) concludes that
âvulnerabilities rather than opportunities are the most striking consequence of smallnessâ. It has
been recently claimed that, since they cannot defend or represent themselves adequately, small
states âlack real independence, which makes them suboptimal participants in the international
systemâ (Hagalin, 2005: 1).
There is however, a less notable and acknowledged but more extraordinary strand of
argumentation that considers âthe power of powerlessnessâ, and the ability of small states to
exploit their smaller size in a variety of ways in order to achieve their intended, even if unlikely,
policy outcomes. The pursuance of smaller state goals becomes paradoxically acceptable and
achievable precisely because such smaller states do not have the power to leverage disputants or
pursue their own agenda. A case in point concerns the smallest state of all, the Vatican, whose
powers are both unique and ambiguous, but certainly not insignificant (The Economist, 2007).
Smaller states have âpunched above their weightâ (e.g. Edis, 1991); and, intermittently, political scientists confront their âamazing intractabilityâ (e.g. Suhrke, 1973: 508). Henry Kissinger
(1982: 172) referred to this stance, with obvious contempt, as âthe tyranny of the weakâ3.
This paper seeks a safe passage through these two, equally reductionist, propositions. It
deliberately focuses first on a comparative case analysis of two, distinct âsmall state-big stateâ
contests drawn from the 1970s, seeking to infer and tease out the conditions that enable smaller
âLilliputianâ states (whether often or rarely) to beat their respective Goliaths. The discussion is
then taken forward to examine whether similar tactics can work in relation to contemporary
concerns with environmental vulnerability, with a focus on two other, small island states. Before
that, the semiotics of âthe small stateâ need to be explored, since they are suggestive of the
perceptions and expectations that are harboured by decision makers at home and abroad and
which tend towards the self-fulfilling prophecy.peer-reviewe
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