bluuebunny/crossref_metadata_2025 huggingface dataset:
Parental Overprotection and Metacognitions as Predictors of Worry and Anxiety
Authors: Spada Marcantonio M. , Caselli Gabriele , Manfredi Chiara , Rebecchi Daniela , Rovetto Francesco , Ruggiero Giovanni M. , Nikčević Ana V. , Sassaroli Sandra
Published: June 2011

Background: Parental overprotection may have a direct effect on worry through hindering children's exploration experiences and preventing the learning of action-oriented coping strategies (Cheron, Ehrenreich and Pincus, 2009; Nolen-Hoeksema, Wolfson, Mumme and Guskin, 1995) and an indirect effect through fostering the development of maladaptive metacognitions that are associated with the activation of worry and the escalation of anxiety (Wells, 2000). Aim: The aim was to investigate the relative contribution of recalled parental overprotection in childhood and metacognitions in predicting current levels of worry. Method: A community sample (n = 301) was administered four self-report instruments to assess parental overprotection, metacognitions, anxiety and worry. Results: Metacognitions were found to predict levels of worry independently of gender, anxiety and parental overprotection. They were also found to predict anxiety independently of gender, worry and parental overprotection. Conclusions: The combination of a family environment perceived to be characterized by overprotection and high levels of maladaptive metacognitions are a risk factor for the development of worry.
Bimanual-Vertical Hand Movements
Authors: Kwon Jay C. , Cohen Matthew L. , Williamson John , Burtis Brandon , Heilman Kenneth M.
Published: June 2011

Patients often demonstrate attentional and action-intentional biases in both the transverse and coronal planes. In addition, when making forelimb movements in the transverse plane, normal participants also have spatial and magnitude asymmetries, but forelimb spatial asymmetries have not been studied in coronal space. Thus, to learn if when normal people make vertical movements they have right–left spatial and magnitude biases, seventeen healthy, blindfolded volunteers had their hands (holding pens) placed vertically in their midsagittal plane, 10 inches apart, on pieces of paper positioned above, below, and at eye-level. Participants were asked to move their hands together vertically and meet in the middle. Participants demonstrated less angular deviation in the below-eye condition than in the other spatial conditions, when moving down than up, and with their right than left hand. Movements toward eye level from upper or lower space were also more accurate than movements in the other directions. Independent of hand, lines were longer with downward than upward movements and the right hand moved more distance than the left. These attentional-intentional asymmetries may be related to gravitational force, hand-hemispheric dominance, and spatial “where” asymmetries; however, the mechanisms accounting for these asymmetries must be ascertained by future research. (JINS, 2011,17, 732–739)
When Gender and Party Collide: Stereotyping in Candidate Trait Attribution
Authors: Hayes Danny
Published: June 2011

Research has shown that voters are willing to stereotype candidates on the basis of their gender, which can sometimes pose obstacles and sometimes prove advantageous for female politicians. But the literature is uncertain about how candidate gender interacts with candidate party affiliation to shape voters' perceptions. In this article, I draw on political psychology, the women and politics literature, and recent work on partisan “trait ownership” to suggest that the application of gender stereotypes will be limited by the salience of partisan stereotypes. I use nationally representative survey data and a content analysis of news coverage from the 2006 U.S. Senate elections to test the argument. Focusing on voter evaluations of candidate traits, I find that party stereotypes are more powerful than gender stereotypes, and that assessments of candidate attributes can be affected by news coverage when candidates are portrayed in ways that challenge traditional partisan images. The results suggest that gender stereotyping is limited by the relevance of party stereotypes, and that as the Republican and Democratic parties continue to polarize at the elite level, the importance of partisan stereotyping is likely to increase.
My Heart Says One Thing but My Head Says Another? Men, Women, and the Psychology of Partisanship in Britain
Authors: Johns Robert , Winters Kristi , Campbell Rosie
Published: June 2011

The point of departure for this study is the recent work of Burden (2008) on the “gender gap” in partisanship in the United States. He shows that the preponderance of Democratic identification among women is partly a function of the measurement of party identification. When respondents were asked “Do you feel that you are” rather than, more traditionally, “Do you think of yourself as” a Democrat or Republican, the sex gap narrowed to statistical nonsignificance. Burden's explanation for this result lies in the psychology of partisanship. The traditional “think of yourself as” (or cognitive) question primes women to consider their partisanship as a social identity, which in turn activates the stereotypical association between women and the Democratic Party. The “feel that you are” (or affective) question encourages a deeper, more personalized response, rendering social identity less relevant and thereby nullifying the effect of that stereotype.
Gender Affinity Effects in Vote Choice in Westminster Systems: Assessing “Flexible” Voters in Canada
Authors: Goodyear-Grant Elizabeth , Croskill Julie
Published: June 2011

Under certain conditions, women are more likely than men to vote for women candidates, a phenomenon referred to as a “gender affinity effect.” Causal mechanisms connecting women voters to women candidates are gender consciousness, desire for descriptive representation, support for liberal social policy, the use of gender as a shortcut to vote choice among low-information voters, and a “party-sex overlap.” Existing work is focused on American elections, which tend to be candidate centered, so little is known about gender affinity effects between voters and candidates in other contexts. This article focuses on Westminster-style parliamentary systems, using the Canadian federal elections of 2000 and 2004 as test cases. Women in these systems have the same motivations to gravitate toward women candidates, for they are gender conscious and desire descriptive representation. But they do not have the same incentives to cast ballots for women because political institutions and practices tend to discourage candidate-based voting. The article pays particular attention to a segment of the electorate we call “flexible” voters, which is comprised of independents, leaners, and defectors. In Westminster systems, it is this group of voters who should be most sensitive to candidate-based considerations.
Informal Institutions, Protest, and Change in Gendered Federal Systems
Authors: Banaszak Lee Ann , Weldon S. Laurel
Published: June 2011

Federalism seems to play a widely varying role in maintaining or undermining gender hierarchies around the world. In 1869, for example, federalism allowed Wyoming—a new state in the United States—to enfranchise women before this happened at the national level. But in Switzerland, federalism let a recalcitrant canton disenfranchise women until the 1990s—20 years after women achieved the vote on the national level (Banaszak 1996). More generally, federal institutions are associated with widely varying policies on women's rights. Table 1 groups countries according to Lijphart's (1999, Chapter 10) three measures of federalism: a numerical summary measure (column 2), whether the country is centralized or decentralized (column 3), and a dichotomous measure of federal or unitary based on the country's constitution (column 4). No matter which measure is used, gender equality policies vary greatly within each type of system. The wide variation within each category suggests that standard approaches to federalism give us little purchase on gender politics.
Gender Policy and State Architecture in Latin America
Authors: Franceschet Susan
Published: June 2011

Latin American countries display wide variation in gender equality and organized women's capacity to mobilize and influence policy outcomes. Yet there are also many similarities in the region's political systems and sociocultural contexts that affect women's politics and its impact. These include presidential systems that, in theory, divide power among the executive, legislative, and judicial branches, but often concentrate power in the executive; deep social and regional inequalities; and the influence of organized religion. How these factors affect women's lives, however, is also shaped by vertical divisions of powers. Although only four Latin American states are federations (Argentina, Brazil, Mexico, and Venezuela), most other countries undertook decentralization in the last two decades, transferring service delivery and program implementation (but not taxing authority) to regional or local levels. Because in some cases decentralization occurred under authoritarian regimes, or in newly democratizing states in the midst of fiscal crises, it has not ultimately deepened Latin American democracy.
State Structures and The Politics of Child Care
Authors: Brennan Deborah , Mahon Rianne
Published: June 2011

New and reconfigured structures of policymaking and governance present fresh challenges to gender equality seekers, especially in federal systems. In a world in which policy functions are increasingly being “uploaded” to international or supranational levels, “downloaded” to meso-level units, or “offloaded” to civil society and private enterprises (Banaszak, Beckwith, and Rucht 2003), the links among institutional design, policy activism, and policy outcomes provide fruitful opportunities for empirical research and theory building. This essay asks what impact state architectures have on women's political mobilization around child care. How might we theorize the effects of different types of federation and multilevel governance on child-care activists' political opportunities and achievement of policy outcomes? How adequate are existing frameworks for explaining links among policy actors, state institutions, civil society, and international business? We sketch some preliminary answers and show how recognizing the significance of the multiple scales and layers involved in contemporary governance can expand feminist research agendas and promote gender-sensitive policymaking. Child care is increasingly understood as an essential component of contemporary welfare states (Michel and Mahon 2002). Well-designed child-care programs help time-pressed earner parents reconcile work and family life and make it possible for lone parents to improve their economic situation through paid work. Universal early childhood education and care (ECEC) also lays the foundations for lifelong learning, indispensable for success in knowledge-based, postindustrial economies. Adequate public support for ECEC systems generates good postindustrial jobs for early childhood educators who work in publicly financed, regulated settings instead of in low-paid, informal, caregiving situations (Esping-Andersen 1999). Developing high-quality, universal ECEC in federal systems with divided jurisdictional responsibility, however, faces particular challenges. Most comparative social policy and welfare regime literature ignores state architectures by assuming that unitary state forms are the norm and focusing purely on nation-state governments and policymaking (Esping-Andersen 1999). Advocacy and policy initiatives on international or meso-level scales typically are ignored or underexplored.
The Victoria Schuck Award: A Sonata for Gender Politics Scholarship
Authors: Tolleson-Rinehart Sue
Published: June 2011

Even as this issue of Politics & Gender appears in print, a committee of scholars (Kimberly Morgan, Vanita Seth, and Wendy Gunther-Canada in 2011) is serving the discipline by undertaking the fascinating and painful task of choosing a book (or books) upon which to bestow the American Political Science Association's Victoria Schuck Award for Best Book on Gender Politics. Twenty three committees have given the award to 32 books since the first awards were made in 1988. The Schuck Award is one of only four association-wide book awards (the others, of course, are the Ralph Bunche Award for ethnic and cultural pluralism; the Gladys Kammerer Award for best book in U.S. national policy; and the Woodrow Wilson Award for Best Book as chosen by the Woodrow Wilson Foundation on government, politics, or international relations). How did the young field of gender politics reach such heights of scholarly recognition so soon?
SNIPER SHOT PEGylation: TGase mediated site-specific conjugation of PEG to proteins
Authors: Satwekar Abhijeet
Published: June 2011

Commercially available recombinant protein drugs often cause immune reactions in the body which reduces their efficiency. Protein drugs can be PEGylated, (attachment of polyethylene glycol) to overcome this problem. PEGylation increases bioavailability by reduced immune reactions and decreased renal clearance [1]. So far the traditional approaches for PEGylation involve harsh reaction conditions which provide a heterogeneous product (PEG attached randomly to different sites) along with the formation of several byproducts. Due to heterogeneity, the PEGylated protein drug faces challenge for FDA approval. Therefore, there is an immense need to develop an approach which could generate a homogeneous PEGylated protein drug.The transglutaminase (TGase) is an enzyme which catalyzes specifically the formation of a covalent bond (-CONH-) between the glutamine residue and the amine group of the lysine. This TGase reaction can be engineered by substituting the lysine with primary amines, which results in the formation of a similar covalent bond between the glutamine and the primary amine [2]. We utilized the specificity of TGase by using primary PEG-amines for conjugation with the glutamine present in the model protein (apomyoglobin). The reaction conditions were optimized in order to get a mono-conjugated PEGylated derivative. The site of conjugation was determined by affinity purification of the modified peptides and characterized by the ESI Q-TOF mass spectrometer. Therefore, we were able to develop a site-specific PEGylated apomyoglobin without byproducts, which eventually reduced the derivative purification steps as compared with the traditional PEGylation approaches. This strategy was further implemented on commercial pharmaceutical proteins.
SBGN-PD: Current status, future changes and unresolved issues
Authors: Moodie Stuart
Published: June 2011

SBGN PD is currently at Level 1 Version 1.2, which is a maintenance release. The next release will be L1 Version 2.0, which will incorporate changes to the state glyph, add the annotation glyph and change the semantics of complex sub-units. These issues may be discussed further as will some unresolved issues in the specification.
A modelling study of beta-amyloid induced change in hippocampal theta rhythm
Authors: Zou Xin , Coyle Damien , Wong-Lin KongFatt , Maguire Liam
Published: June 2011

Many dementia cases, such as Alzheimer’s disease (AD), are characterized by an increase in low frequency field potential oscillations. However, a definitive understanding of the effects of the beta-Amyloid peptide, which is a main marker of AD, on the low frequency theta rhythm (4-7Hz) is still unavailable. In this work, we investigate the neural mechanisms associated with beta-Amyloid toxicity using a conductance-based neuronal network model of the hippocampus CA1 region. We simulate the effects of beta-Amyloid on the A-type fast inactivating K+ channel by modulating the maximum conductance of the current in pyramidal cells, denoted by gA. Our simulation results demonstrate that as gA decreases (through A[beta]blockage), the theta band power first increases then decreases. Thus there exists a value of gA that maximizes the theta band power. The neuronal and network mechanism underlying the change in theta rhythm is systematically analyzed. We show that the increase in theta power is due to the improved synchronization of pyramidal neurons, and the theta decrease is induced by the faster depolarisation of pyramidal neurons.
A Novel Thermodynamic Method For Quantifying Ligand-Receptor Interactions: The IC (1/3) Standard Vs IC (50)
Authors: Prasad Sudarsan
Published: June 2011

A method based on the Concentration Derivative Product (CDP) is proposed to analyze the thermodynamics of Drug-Receptor interactions. CDP is defined as the product of the fractional inhibition f and it’s concentration derivative. Assuming Michaelis-Menten kinetics, it is shown that for a number of drug-receptor systems (HIV protease, ACE, HMG-CoA, Opioid receptor inhibitors, etc.) f max = 0.333, irrespective of the nature of bonding interactions and Ki. The CDP max = [4 / ( 27 Ki ) ], and gives a measure of the drug potency directly. CDP also gives thermodynamic information about the ratio of the gradients of the inhibitor chemical potential in the free and bound states.
Troublesome Threesome: Feminism, Anthropology and Muslim Women's Piety
Authors: Jacobsen Christine M
Published: June 2011

This article critically addresses recent anthropological and feminist efforts to theorize and analyse Muslim women's participation in and support for the Islamic revival in its various manifestations. Drawing on ethnographic material from research on young Muslims engaged in Islamic youth and student-organizations in Norway, I investigate some of the challenges that researching religious subjectivities and practices pose to feminist theory. In particular, I deal with how to understand women's religious piety in relation to questions of self, agency and resistance. Engaging with Saba Mahmood's work on The Politics of Piety, this article suggests ways of understanding the young women's religious engagement that move beyond the confines of a binary model of subordination and resistance, coercion and choice. Grounding the discussion in ethnographic analysis of how young Muslim women in Norway speak about the ‘self’, I argue that critically revisiting feminist notions of agency, autonomy and desire, is necessary in order to understand the kinds of self-realization that these women aspire to. However, the article argues against positing Muslim conceptions and techniques of the self as ‘the other’ of liberal-secular traditions. Rather, I show how configurations of personhood, ethics and self-realization drawn from Islamic and liberal-secular discursive formations inhabit not only the same cultural and historical space, but also shape individual subjectivities and modes of agency.
Not-/Unveiling as An Ethical Practice
Authors: Fadil Nadia
Published: June 2011

The practice of Islamic veiling has over the last ten years emerged into a popular site of investigation. Different researchers have focused on the various significations of this bodily practice, both in its gendered dimensions, its identity components, its empowering potentials, as a satorial practice or as part of a broader economy of bodily practices which shape pious dispositions in accordance with the Islamic tradition. Lesser, however, has this been the case for the practice of not veiling or unveiling. If and when attention is accorded to the latter, it is often grasped as a product of integration or an effect secular governmentality, but only rarely as a bodily practice. Drawing on narratives of second generation secular and religious Maghrebi Muslims in Belgium, this paper pursues this second perspective by examining to which extent not-veiling can be understood as a technique of the self (Foucault) that is functional to shaping a liberal (Musilm) subject. While a first part of this article will unpack the ethical substance of such discursive interrogations and point to the ways in which they are intertwined with the enactment of a liberal self, the second part will examine the embodied contours of this problematization, which appeared through the labour upon one's affect and bodily dispositions that this refusal of the hijab, or the act of unveiling, implies.
Regimes of Visibility: Representing Violence against Women in the French Banlieue
Authors: Dornhof Sarah
Published: June 2011

Recent discussions about violence against women have shifted their attention to specific forms of violence in relation to migration and Islam. In this article, I consider different modes of representing women's experiences in French immigrant communities. These representations relate to the French feminist movement Ni Putes Ni Soumises (neither whore nor submissive), a movement that in the early 2000s deplored both the sustained degradation of certain banlieue neighborhoods and also the charges and restrictions that this entails, particularly for young women. Drawing on different narratives and images of women's painful experience, I consider, in a first step, how the question of representing violence against (post)migrant women is framed in terms of the tension between universality and particularity within French republicanism. In the next part of my argument, I bring into focus the question of how to access women's suffering. For a perspective on pain not as an interiorized, private experience but as an accessible complex of practices, articulations, memories, visions and social reconfigurations, I consider Smaïn Laacher's sociological study (2008) about written testimonies of violent experience that had been addressed by (post)migrant women to French women organizations such as Ni Putes Ni Soumises. I finally suggest reading women's accounts on violence not in relation to a universal discourse of rights, but as a political contestation of the naturalized order of representing violence, suffering and agency inside French banlieue communities. Drawing on Jacques Rancière's notion of dissensus, such a contestation can be staged through words by those who have no visibility in the representational order, words not to criticize the unaccomplished ideals of universal equality, but to create a universal community and a common language of experience in the mode of ‘as-if’.
Subjects of Debate: Secular and Sexual Exceptionalism, and Muslim Women in the Netherlands
Authors: Bracke Sarah
Published: June 2011

This article attends to the transformation of national identity that occurs in the context of ‘the multicultural debate’ in the Netherlands, and unfolds on the terrain of Dutch (secular and sexual) exceptionalism. First, it explores the connections between two topics that are prominent in the ‘multicultural debates’ all over Europe and undergird the civilizational discourse of a post-Cold War geopolitical era: discussions about secularism on the one hand, and gender and sexual politics on the other. Through a mode of ‘secular nostalgia’, which mobilizes the understanding of the Netherlands as a place par excellence of emancipation for both women and sexual minorities, the Dutch secular arrangement is restructured in new exclusionary ways. Second, it explores how dominant discourses on the symbolic and material borders of the nation interpellate young Muslim women who often figure as the central ‘subjects of debate’. I rely on the notion of interpellation (Althusser) to explore the question of subject formation, with a particular attention to the epistemological conditions of ‘talking back’ as a subject whose constituency and agency is always already informed by the terms in which she is addressed.
Gender, Migration and the Ambiguous Enterprise of Professionalizing Domestic Service: The Case of Vocational Training for the Unemployed in France
Authors: Scrinzi Francesca
Published: June 2011

This article aims to contribute to current debates about international migration and the restructuring of the Welfare state in Europe, by highlighting the specificities of the French context. It draws on ethnographic research about the training of unemployed migrant women as domestic workers in Paris to address the ambiguities that underlie the enterprise of professionalizing domestic service. The qualitative data presented in the article show how essentialist ideologies operate within training practices of domestic workers. They reveal that the training practices challenge the association of the job with domesticity, but fail to acknowledge the racist organization of domestic service. Hence, they endorse essentialist constructions of cultural difference. Training practices are also consistent with current neoliberal policies and discourses on unemployment and ‘employability’, as they are framed by the normative reference to an entrepreneurial model of society. Finally, the data suggest that migrant women's experience of domestic service as a prospective job and their scepticism about the enterprise of professionalizing radically differ from the instructors’ views.
Disowning Dependence: Single Women's Collective Struggle for Independence and Land Rights in Northwestern India
Authors: Berry Kim
Published: June 2011

In April 2008 over 2,600 single women marched for three days to Shimla, the state capital of the northwestern Indian state of Himachal Pradesh, to demand rights to land, health care and ration cards for single women. The march was organized by a new social movement called Ekal Nari Shakti Sangathan, comprising divorced, abandoned, never-married women, widows and wives fleeing domestic violence who are demanding rights from the state in their own names (rather than as wives, daughters or mothers); in so doing they are directly challenging the construct of the ‘dependent woman’ naturalized in pre-colonial, colonial and post-colonial discourses. The most radical of the demands of this new social movement is the struggle for land rights and the creation of new women-centred family formations. Through an analysis of their collective demands, I argue that the normative, dependent woman is mutually constituted not only at the intersections of gender, kinship and heterosexuality, but also spatially, through denial of rights to land. As single women disown their dependence upon husbands/fathers/brothers and demand land rights, they simultaneously re-imagine gendered selves by envisioning new marital families and re-working the division of labour.
Debye shielding in a nonextensive plasma
Authors: Ait Gougam Leila , Tribeche Mouloud
Published: June 2011

The phenomenon of Debye Shielding is revisited within the theoretical framework of the Tsallis statistical mechanics. The plasma consists of nonextensive electrons and ions. Both the effective Debye length λDq and the fall-off of the electrostatic potential Φ are considered and a parameter study conducted. Owing to electron nonextensivity, the critical Mach number derived from the modified Bohm sheath criterion may become less than unity allowing therefore ions with speed less than ion-acoustic speed to enter the sheath from the main body of the plasma. Considering the wide relevance of collective processes, our analysis may be viewed as a first step toward a more comprehensive Debye shielding and electrostatic plasma sheath in nonequilibrium plasmas.
MnP films and MnP nanocrystals embedded in GaP epilayers grown on GaP(001): Magnetic properties and local bonding structure
Authors: de Andrés A. , Espinosa A. , Prieto C. , García-Hernández M. , Ramírez-Jiménez R. , Lambert-Milot S. , Masut R. A.
Published: June 2011

MnP nanostructures embedded in GaP epilayers, and MnP polycrystalline films, grown from the vapor phase on GaP(001) substrates using metalorganic precursors are compared with bulk MnP. We observe a large increase of the low transition temperature from the ferromagnetic to the antiferromagnetic screw phase, from TN = 47 K for bulk to 82 K for nanocrystals in MnP:GaP films, while the Curie temperature TC, close to room temperature, varies only slightly. A net magnetic moment is measured in the nanocrystals and films at 5 K, as well as large coercive fields, contrary to bulk MnP. X-ray absorption spectroscopy and diffraction show that epilayers and films contain MnP grains in the nanometric range with average Mn–P bond lengths very close to those of bulk MnP. The MnP film lattice parameters are almost identical to bulk values (within 0.5%) and the main crystallographic preferential orientations are those also present in the epilayers but with different relative populations. Overall the local structures of all MnP forms are very similar, except for indications of more disorder in the nanocrystals. Such combined changes of TN and TC are in apparent contradiction with the known response of bulk MnP to strains induced by hydrostatic, uniaxial or chemical pressure. We conclude that the differences in the low temperature magnetic behavior are most probably originated by local structural disorder at the surface of the nanostructures and by finite size effects.
Electron trapping in 4H-SiC MOS capacitors fabricated by pre-oxidation nitrogen implantation
Authors: Basile A. F. , Dhar S. , Mooney P. M.
Published: June 2011

Incorporation of nitrogen (N) atoms by ion implantation prior to oxidation of SiO2/4H-SiC interfaces has been investigated by capacitance-voltage (C-V) characteristics and constant capacitance deep-level-transient spectroscopy (CCDLTS) measurements. The shift of the C-V curves to negative voltages can be explained by the partial activation of implanted N atoms during oxidation. The maximum amplitude of the CCDLTS spectra, proportional to the density of near-interface oxide traps, decreases with increasing N dose, but remains significantly larger than that of SiO2/SiC interfaces fabricated by post oxidation annealing in nitric oxide (NO). Intrinsic defects in the SiC epi-layer associated with implantation damage are also observed in N-implanted samples. In contrast, electron traps energetically close to the SiC conduction band, detected in NO annealed samples and presumably introduced during oxidation, are not observed in N-implanted samples. The improved transport characteristics of MOS transistors fabricated on N-implanted epi-layers compared to those fabricated by NO annealing is suggested to result from the effects of the greater N donor concentration and also possibly to the suppression of shallow electron traps in the SiC epilayer.
General formulation for acoustic solitons in three-component nonthermal plasmas
Authors: Chuang S.-H. , Hau L.-N.
Published: June 2011

A generalized formulation is developed for nonlinear acoustic solitons in three-component such as dust-ion-electron and electron-positron-ion plasmas with the charge of each species being unspecified. The heavy, cold charged particles (ions or dust particles) are treated as a fluid while the light, hot components are described by the kinetic Vlasov equation with separate velocity distributions which can be of κ function or highly nonthermal (non-monotonic) distributions. The model is also applicable for two-component such as ion-electron plasmas with two different temperatures for electrons. The generalized dispersion relation for acoustic waves and the Korteweg-de Vries equations as well as the Sagdeev potential are derived for various models with different combinations of velocity distributions. The parameter regimes for the existence of acoustic solitons are analyzed and examples of nonlinear solutions are illustrated. The polarity of electric potential is found to exhibit anomaly for highly nonthermal cases.
Ultraviolet photosensitivity of sulfur-doped micro- and nano-crystalline diamond
Authors: Mendoza Frank , Makarov Vladimir , Hidalgo Arturo , Weiner Brad , Morell Gerardo
Published: June 2011

The room-temperature photosensitivity of sulfur-doped micro-, submicro-, and nano-crystalline diamond films synthesized by hot-filament chemical vapor deposition was studied. The structure and composition of these diamond materials were characterized by Raman spectroscopy, scanning electron microscopy, and x-ray diffraction. The ultraviolet (UV) sensitivity and response time were studied for the three types of diamond materials using a steady-state broad UV excitation source and two pulsed UV laser radiations. It was found that they have high sensitivity in the UV region (as high as 109 s−1 mV−1 range), a linear response in a broad spectral range below 320 nm, photocurrents around ∼10−5 A, and a short response time better than 100 ns, which is independent of fluency intensity. A phenomenological model was applied to help understand the role of defects and dopant concentration on the materials’ photosensitivity.
Wave kinetics of relativistic quantum plasmas
Authors: Mendonça J. T.
Published: June 2011

A quantum kinetic equation, valid for relativistic unmagnetized plasmas, is derived here. This equation describes the evolution of a quantum quasi-distribution, which is the Wigner function for relativistic spinless charged particles in a plasma, and it is exactly equivalent to a Klein-Gordon equation. Our quantum kinetic equation reduces to the Vlasov equation in the classical limit, where the Wigner function is replaced by a classical distribution function. An approximate form of the quantum kinetic equation is also derived, which includes first order quantum corrections. This is applied to electron plasma waves, for which a new dispersion relation is obtained. It is shown that quantum recoil effects contribute to the electron Landau damping with a third order derivative term. The case of high frequency electromagnetic waves is also considered. Its dispersion relation is shown to be insensitive to quantum recoil effects for equilibrium plasma distributions.
Renormalized non-modal theory of the kinetic drift instability of plasma shear flows
Authors: Mikhailenko V. S. , Mikhailenko V. V. , Stepanov K. N.
Published: June 2011

The linear and renormalized nonlinear kinetic theory of drift instability of plasma shear flow across the magnetic field, which has the Kelvin’s method of shearing modes or the so-called non-modal approach as its foundation, is developed. The developed theory proves that the time-dependent effect of the finite ion Larmor radius is the key effect, which is responsible for the suppression of drift turbulence in an inhomogeneous electric field. This effect leads to the non-modal decrease of the frequency and growth rate of the unstable drift perturbations with time. We find that turbulent scattering of the ion gyrophase is the dominant effect which determines the extremely rapid suppression of drift turbulence in shear flow.
Three-dimensional electromagnetic strong turbulence. I. Scalings, spectra, and field statistics
Authors: Graham D. B. , Skjaeraasen O. , Robinson P. A. , Cairns Iver H.
Published: June 2011

The first fully three-dimensional (3D) simulations of large-scale electromagnetic strong turbulence (EMST) are performed by numerically solving the electromagnetic Zakharov equations for electron thermal speeds νe with νe/c≥0.025. The results of these simulations are presented, focusing on scaling behavior, energy density spectra, and field statistics of the Langmuir (longitudinal) and transverse components of the electric fields during steady-state strong turbulence, where multiple wave packets collapse simultaneously and the system is approximately statistically steady in time. It is shown that for νe/c≳0.17 strong turbulence is approximately electrostatic and can be explained using the electrostatic two-component model. For ve/c≳0.17 the power-law behaviors of the scalings, spectra, and field statistics differ from the electrostatic predictions and results because νe/c is sufficiently high to allow transverse modes to become trapped in density wells. The results are compared with those of past 3D electrostatic strong turbulence (ESST) simulations and 2D EMST simulations. For number density perturbations, the scaling behavior, spectra, and field statistics are shown to be only weakly dependent on νe/c, whereas the Langmuir and transverse scalings, spectra, and field statistics are shown to be strongly dependent on νe/c. Three-dimensional EMST is shown to have features in common with 2D EMST, such as a two-component structure and trapping of transverse modes which are dependent on νe/c.
A versatile facility for laboratory studies of viscoelastic and poroelastic behaviour of rocks
Authors: Jackson Ian , Schijns Heather , Schmitt Douglas R. , Mu Junjie , Delmenico Alison
Published: June 2011

Novel laboratory equipment has been modified to allow both torsional and flexural oscillation measurements at sub-microstrain amplitudes, thereby providing seismic-frequency constraints on both the shear and compressional wave properties of cylindrical rock specimens within the linear regime. The new flexural mode capability has been tested on experimental assemblies containing fused silica control specimens. Close consistency between the experimental data and the results of numerical modelling with both finite-difference and finite-element methods demonstrates the viability of the new technique. The capability to perform such measurements under conditions of independently controlled confining and pore-fluid pressure, with emerging strategies for distinguishing between local (squirt) and global (specimen-wide) fluid flow, will have particular application to the study of frequency-dependent seismic properties expected of cracked and fluid-saturated rocks of the Earth's upper crust.
Kinetic simulations of thermal escape from a single component atmosphere
Authors: Volkov Alexey N. , Tucker Orenthal J. , Erwin Justin T. , Johnson Robert E.
Published: June 2011

The one-dimensional steady-state expansion of a monatomic gas from a spherical source in a gravity field is studied by the direct simulation Monte Carlo method. Collisions between molecules are described by the hard sphere model, the distribution of gas molecules leaving the source surface is assumed to be Maxwellian, and no heat is directly deposited in the simulation region. The flow structure and the escape rate (number flux of molecules escaping the atmosphere) are analyzed for the source Jeans parameter λ0 (ratio of the gravitational energy to thermal energy of the molecules) and Knudsen number Kn0 (ratio of the mean free path to the source radius) ranging from 0 to 15 and from 0.0001 to ∞, respectively. In the collisionless regime, flows are analyzed for λ0=0-100 and analytical equations are obtained for asymptotic values of gas parameters that are found to be non-monotonic functions of λ0. For collisional flows, simulations predict the transition in the nature of atmospheric loss from escape on a molecule-by-molecules basis, often referred to as Jeans escape, to an organized outflow, often referred to as hydrodynamic escape. It is found that the structure of the flow and the escape rate exhibit drastic changes when λ0 varies over a narrow transition range 2-3. The lower limit of this range approximately corresponds to a critical Jeans parameter equal to 2.06, which is the upper limit for isentropic, supersonic outflow of a monatomic gas from a body in a gravity field. Subcritical, λ0≤2, flows are qualitatively similar to free outgassing in the absence of gravity, resulting in hypersonic terminal Mach numbers and escape rates that are independent of λ0 in the limit of small Knudsen numbers. Supercritical, λ0≥3, flows are controlled by thermal conduction and demonstrate qualitatively different trends. The ratio of the actual escape rate to the Jeans escape rate at the source surface is found to be a non-monotonic function of Kn0 spanning the range from ∼0.01 to ∼2. At λ0≥6, the ratio of the actual escape rate to the Jeans escape rate at the exobase is found to be ∼1.4–1.7. This is unlike the predictions of the slow hydrodynamic escape model, which is based on Parker’s model for the solar wind and intended for the description of the atmospheric loss at λ0>∼10. At λ0<6, the actual escape rate can be well approximated by a modified Jeans escape rate, which accounts for non-zero gas velocity.
Solid phase phosphorous activation in implanted silicon by excimer laser irradiation
Authors: Fisicaro G. , Italia M. , Privitera V. , Piccitto G. , Huet K. , Venturini J. , La Magna A.
Published: June 2011

The activation mechanism in phosphorous implanted silicon under excimer laser irradiation is investigated. The activation efficiency in the solid phase has been measured in a wide range of irradiation conditions, tuning the laser fluence in the sub-, partial, and total melting regime. Moreover, fixing the fluence, the activation as a function of the shot number has been analyzed. The total active fraction varies by several orders of magnitude and shows a complex trend depending on the process conditions. Our model, based on the interaction between defects and the active/inactive impurities, explains this scenario. In particular, it predicts experimental P active profiles, thus demonstrating that the status of the defect system rules the activation phenomenon, where the coupling between dopant and defect clusters at the early irradiation stage plays a crucial role.
Effect of chain conformation in the phonon transport across a Si-polyethylene single-molecule covalent junction
Authors: Sasikumar Kiran , Keblinski Pawel
Published: June 2011

We use nonequilibrium molecular dynamics simulations to study heat transfer across molecular junctions formed by alkane chains covalently bonded to crystalline silicon leads. We focus our studies on the role of chain conformation on phonon transport across junctions and along the chain. We find that in the case of straight chains, all trans conformations, the silicon-polyethylene junction conductance is 180 pW/K, and heat flows ballistically, i.e. with no resistance, along the chain. The introduction of gauche conformations (kinks) leads to a nonzero thermal resistance of the chain and also reduces the junction conductance to 100 pW/K. The chain thermal resistance is proportional to the number of gauche conformations indicating that they act as strong and independent phonon scattering centers. We attribute the 80% enhancement in junction conductance during extension from coiled to straight chain conformation to ballistic (coherent) phonon transport along a straight chain.
Nanothermochromics with VO2-based core-shell structures: Calculated luminous and solar optical properties
Authors: Li S.-Y. , Niklasson G. A. , Granqvist C. G.
Published: June 2011

Composites including VO2-based thermochromic nanoparticles are able to combine high luminous transmittance Tlum with a significant modulation of the solar energy transmittance ΔTsol at a “critical” temperature in the vicinity of room temperature. Thus nanothermochromics is of much interest for energy efficient fenestration and offers advantages over thermochromic VO2-based thin films. This paper presents calculations based on effective medium theory applied to dilute suspensions of core-shell nanoparticles and demonstrates that, in particular, moderately thin-walled hollow spherical VO2 nanoshells can give significantly higher values of ΔTsol than solid nanoparticles at the expense of a somewhat lowered Tlum. This paper is a sequel to a recent publication [S.-Y. Li, G. A. Niklasson, and C. G. Granqvist, J. Appl. Phys. 108, 063525 (2010)].
Effects of ozone exposure on ‘Golden’ papaya fruit by photoacoustic phase-resolved method: Physiological changes associated with carbon dioxide and ethylene emission rates during ripening
Authors: Corrêa Savio Figueira , Mota Leonardo , Paiva Luisa Brito , Couto Flávio Mota do , Silva Marcelo Gomes da , Oliveira Jurandi Gonçalves de , Sthel Marcelo Silva , Vargas Helion , Miklós András
Published: June 2011

This work addresses the effects of ozone activity on the physiology of ‘Golden’ papaya fruit. Depth profile analysis of double-layer biological samples was accomplished using the phase-resolved photoacoustic spectroscopy. The feasibility of the method was demonstrated by singling out the spectra of the cuticle and the pigment layers of papaya fruit. The same approach was used to monitor changes occurring on the fruit during ripening when exposed to ozone. In addition, one has performed real time studies of fluorescence parameters and the emission rates of carbon dioxide and ethylene. Finally, the amount of pigments and the changes in waxy cuticle have been monitored. Results indicate that a fruit deliberately subjected to ozone at a level of 6 ppmv underwent ripening sooner (at least 24-48 h) than a fruit stored at ambient conditions. Moreover, ozone caused a reduction in the maximum quantum yield of photosynthetic apparatus located within the skin of papaya fruit.
Hilbert space for quantum mechanics on superspace
Authors: Coulembier K. , De Bie H.
Published: June 2011

In superspace a realization of \documentclass[12pt]{minimal}\begin{document}$\mathfrak {sl}_2$\end{document}sl2 is generated by the super Laplace operator and the generalized norm squared. In this paper, an inner product on superspace for which this representation is skew-symmetric is considered. This inner product was already defined for spaces of weighted polynomials (see [K. Coulembier, H. De Bie, and F. Sommen, Orthogonality of Hermite polynomials in superspace and Mehler type formulae, Proc. London Math. Soc. (accepted) arXiv:1002.1118]). In this article, it is proven that this inner product can be extended to the super Schwartz space, but not to the space of square integrable functions. Subsequently, the correct Hilbert space corresponding to this inner product is defined and studied. A complete basis of eigenfunctions for general orthosymplectically invariant quantum problems is constructed for this Hilbert space. Then the integrability of the \documentclass[12pt]{minimal}\begin{document}$\mathfrak {sl}_2$\end{document}sl2-representation is proven. Finally, the Heisenberg uncertainty principle for the super Fourier transform is constructed.
Reduction in thermal boundary conductance due to proton implantation in silicon and sapphire
Authors: Hopkins Patrick E. , Hattar Khalid , Beechem Thomas , Ihlefeld Jon F. , Medlin Douglas L. , Piekos Edward S.
Published: June 2011

We measure the thermal boundary conductance across Al/Si and Al/Al2O3 interfaces that are subjected to varying doses of proton ion implantation with time domain thermoreflectance. The proton irradiation creates a major reduction in the thermal boundary conductance that is much greater than the corresponding decrease in the thermal conductivities of both the Si and Al2O3 substrates into which the ions were implanted. Specifically, the thermal boundary conductances decrease by over an order of magnitude, indicating that proton irradiation presents a unique method to systematically decrease the thermal boundary conductance at solid interfaces.
A comparative study of Raman enhancement in capillaries
Authors: Eftekhari Fatemeh , Irizar Juan , Hulbert Laila , Helmy Amr S.
Published: June 2011

This work reports on the comparative studies of Raman enhancement in liquid core waveguides (LCWs). The theoretical considerations that describe Raman enhancement in LCWs is adapted to analyze and compare the performance of hollow core photonic crystal fibers (HCPCFs) to conventional Teflon capillary tubes. The optical losses in both platforms are measured and used to predict their performance for different lengths. The results show that for an optimal waveguide length, two orders of magnitude enhancement in the Raman signal can be achieved for aqueous solutions using HCPCFs. This length, however, cannot be achieved using normal capillary effects. By integrating the interface of the fluidic pump and the HCPCF into a microfluidic chip, we are able to control fluid transport and fill longer lengths of HCPCFs regardless of the viscosity of the sample. The long-term stability and reproducibility of Raman spectra attained through this platform are demonstrated for naphthalenethiol, which is a well-studied organic compound. Using the HCPCF platform, the detection limit of normal Raman scattering in the range of micro-molars has been achieved. In addition to the higher signal-to-noise ratio of the Raman signal from the HCPCF-platform, more Raman modes of naphthalenethiol are revealed using this platform.