bluuebunny/crossref_metadata_2025 huggingface dataset:
East German Goth and the Spectres of Marx
Authors: van Elferen Isabella
Published: January 2011

The East of Germany, theBundesländerof the former GDR, is an important centre of Goth activity. The Goth scene is remarkably large in this part of Germany, and one of the most important yearly Goth festivals, theWave-Gotik-Treffen, takes place in Leipzig. This article investigates the specific characteristics and internal dynamics of East German Goth subcultures after German reunification. Combining subcultural theory and Gothic criticism with Derrida's notions of spectrality and hauntology, the potentials of Gothic as a form of cultural criticism are explored in an investigation of the psycho-social wasteland of the undead GDR. It will be argued that post-Cold War unification has not only led to a new political order, but has also given rise to a new type of Gothicism, as East German Goth subculture is haunted by ‘spectres of Marx’ that provide a critical engagement with globalised capital and media. As a specifically German version of the worldwide Goth scene, moreover, it marks the local boundedness of globalised subcultures.
What principles should govern the use of managed entry agreements?
Authors: Klemp Marianne , Frønsdal Katrine B. , Facey Karen
Published: January 2011

Background: To ensure rapid access to new potentially beneficial health technologies, obtain best value for money, and ensure affordability, healthcare payers are adopting a range of innovative reimbursement approaches that may be called Managed Entry Agreements (MEAs).

Methods: The Health Technology Assessment International (HTAi) Policy Forum sought to identify why MEAs might be used, issues associated with implementation and develop principles for their use. A 2-day deliberative workshop discussed key papers, members' experiences, and collectively addressed four policy questions that resulted in this study.

Results: MEAs are used to give access to new technologies where traditional reimbursement is deemed inappropriate. Three different forms of MEAs have been identified: management of budget impact, management of uncertainty relating to clinical and/or cost-effectiveness, and management of utilization to optimize performance. The rationale for using these approaches and their advantages and disadvantages differ. However, all forms of MEA should take the form of a formal written agreement among stakeholders, clearly identifying the rationale for the agreement, aspects to be assessed, methods of data collection and review, and the criteria for ending the agreement.

Conclusions: MEAs should only be used when HTA identifies issues or concerns about key outcomes and/or costs and/or organizational/budget impacts that are material to a reimbursement decision. They provide patient access and can be useful to manage technology diffusion and optimize use. However, they are administratively complex and may be difficult to negotiate and their effectiveness has yet to be evaluated.
Improving ethics analysis in health technology assessment
Authors: Duthie Katherine , Bond Kenneth
Published: January 2011

Objectives:The aim of this study was to critically examine the current guidance for conducting ethics analysis in health technology assessment (HTA) and to offer recommendations for how to improve this practice.

Methods:MEDLINE, Philosopher's Index, and Google Scholar were searched for articles and reports using the keywords “ethics” and “health technology assessment” and related terms. Bibliographies of all relevant articles were also examined for additional references. A philosophical analysis of the existing guidance was conducted.

Results:We offer three recommendations for improving ethics analysis in HTA. First, ethical and legal issues must be clearly separated so that all policy-relevant questions that the technology raises can be considered clearly and systematically. Second, analysts must make better use of ethics theory and discuss better how particular theoretical approaches and associated analytic tools are selected to make transparent which alternative approaches were considered and why they were rejected. Third, the necessity for philosophical expertise to adequately conduct ethics analysis needs to be acknowledged.

Conclusions:To act on these recommendations for ethics analysis, we offer these three steps forward: acknowledge and use relevant expertise, further develop models for conducting and reporting ethics analyses, and make use of untapped resources in the literature.
Volume 26: Statistics and thanks
Authors: Mäkelä Marjukka , Ilonen Terhi
Published: January 2011

During the 26th year of the International Journal of Technology Assessment in Health Care (IJTAHC), 154 original manuscripts were evaluated. Of these, 70 percent were from Europe and 14 percent from North America, as judged by the address of the first author. At the end of September 2010, sixty-four papers (42 percent of submissions) had been accepted for publication, seventy-two (47 percent) had been rejected, fourteen (9 percent) had been invited to submit a new version, and four (3 percent) were still in review.
Photodynamic diagnosis of bladder cancer compared with white light cystoscopy: Systematic review and meta-analysis
Authors: Mowatt Graham , N'Dow James , Vale Luke , Nabi Ghulam , Boachie Charles , Cook Jonathan A. , Fraser Cynthia , Griffiths T. R. Leyshon
Published: January 2011

Objectives: The aim of this study was to assess the test performance and clinical effectiveness of photodynamic diagnosis (PDD) compared with white light cystoscopy (WLC) in people suspected of new or recurrent bladder cancer.

Methods: A systematic review was conducted of randomized controlled trials (RCTs), nonrandomized comparative studies, or diagnostic cross-sectional studies comparing PDD with WLC. Fifteen electronic databases and Web sites were searched (last searches April 2008). For clinical effectiveness, only RCTs were considered.

Results: Twenty-seven studies (2,949 participants) assessed test performance. PDD had higher sensitivity than WLC (92 percent, 95 percent confidence interval [CI], 80–100 percent versus 71 percent, 95 percent CI, 49–93 percent) but lower specificity (57 percent, 95 percent CI, 36–79 percent versus 72 percent, 95 percent CI, 47–96 percent). For detecting higher risk tumors, median range sensitivity of PDD (89 percent [6–100 percent]) was higher than WLC (56 percent [0–100 percent]) whereas for lower risk tumors it was broadly similar (92 percent [20–95 percent] versus 95 percent [8–100 percent]). Four RCTs (709 participants) using 5-aminolaevulinic acid (5-ALA) as the photosensitising agent reported clinical effectiveness. Using PDD at transurethral resection of bladder tumor (TURBT) resulted in fewer residual tumors at check cystoscopy (relative risk [RR], 0.37, 95 percent CI, 0.20–0.69) and longer recurrence-free survival (RR, 1.37, 95 percent CI, 1.18–1.59), compared with WLC.

Conclusions: PDD detects more bladder tumors than WLC, including more high-risk tumors. Based on four RCTs reporting clinical effectiveness, 5-aminolaevulinic acid–mediated PDD at TURBT facilitates a more complete resection and prolongs recurrence-free survival.
Novel frameshift mutation in Troponin C (TNNC1) associated with hypertrophic cardiomyopathy and sudden death
Authors: Chung Wendy K. , Kitner Carrie , Maron Barry J.
Published: January 2011

Purpose

Hypertrophic cardiomyopathy is the most common cause of sudden death in young people, including trained athletes, and is caused by mutations in genes encoding proteins of the cardiac sarcomere. Mutations in the Troponin C gene (TNNC1) are a rare genetic cause of hypertrophic cardiomyopathy. We describe a novel type of mutation (c.363dupG) in Troponin C, a rare form of hypertrophic cardiomyopathy.

Methods

A family in which a 19-year-old asymptomatic male died of sudden cardiac death due to hypertrophic cardiomyopathy was genetically studied by sequencing 17 genes associated with hypertrophic cardiomyopathy or its phenocopies.

Results

A c.363dupG mutation in Troponin C was identified, and tested across the family.

Conclusions

We report the first frameshift mutation (c.363dupG or p.Gln122AlafsX30) in Troponin C causing hypertrophic cardiomyopathy (and sudden cardiac death) in a 19-year-old male, and have demonstrated that the mutation segregates with hypertrophic cardiomyopathy within the family.
Atrioventricular septal defect with coexisting tricuspid atresia
Authors: Aiello Vera Demarchi , Afiune Jorge Yussef , Menahem Samuel , Anderson Robert H.
Published: January 2011

We describe two infants having an atrioventricular septal defect in the setting of a double inlet atrioventricular connection, but with patency of the left-sided valvar orifice and an imperforate right-sided valvar component, and a further case with atrioventricular septal defect and an imperforate Ebstein's malformation, all producing the haemodynamic effect of tricuspid atresia. We make comparisons with the arrangement in trisomy 16 mice, in whom deficient atrioventricular septation is seen at times with the common atrioventricular junction exclusively connected to the left ventricle, a situation similar to that seen in two of our infants. We also review previous reports emphasising the important theoretical implication of the findings despite their rarity.
Intelligence's likelihood and evolutionary time frame
Authors: Bogonovich Marc
Published: January 2011

This paper outlines hypotheses relevant to the evolution of intelligent life and encephalization in the Phanerozoic. If general principles are inferable from patterns of Earth life, implications could be drawn for astrobiology. Many of the outlined hypotheses, relevant data, and associated evolutionary and ecological theory are not frequently cited in astrobiological journals. Thus opportunity exists to evaluate reviewed hypotheses with an astrobiological perspective. A quantitative method is presented for testing one of the reviewed hypotheses (hypothesis i; the diffusion hypothesis). Questions are presented throughout, which illustrate that the question of intelligent life's likelihood can be expressed as multiple, broadly ranging, more tractable questions.
When Goal Pursuit Fails
Authors: Epstude Kai , Roese Neal J.
Published: January 2011

Counterfactual thoughts predominantly occur in response to failed goal pursuit. The primary function of self-related counterfactuals seems to be correction of specific behaviors and preparation for future successful goal attainment. In the present article we describe a model that outlines this view of counterfactual thoughts. We focus specifically on automatic versus controlled processes of counterfactual thinking and their relation to the formation of intentions. We link our model to research on goal pursuit, in which the impact of counterfactual thoughts and related affective experiences (e.g., regret) has been somewhat neglected. Implications for research on motivation and goal pursuit are discussed and novel predictions highlighted.
Unintended Allocation of Spatial Attention to Goal-Relevant but Not to Goal-Related Events
Authors: Vogt Julia , De Houwer Jan , Moors Agnes
Published: January 2011

We investigated whether words relevant to a person’s current goal and words related to that goal influence the orienting of attention even when an intention to attend to the goal-relevant and goal-related stimuli is not present. Participants performed a modified spatial cueing paradigm combined with a second task that induced a goal. The results showed that the induced goal led to the orienting of attention to goal-relevant words in the spatial cueing task. This effect was not found for goal-related words. The results provide evidence for accounts of automatic goal pursuit, which state that goals automatically guide attention to goal-relevant events.
Counter-Regulation and Control-Dependency
Authors: Rothermund Klaus
Published: January 2011

Two basic principles governing the motivational regulation of automatic affective processing are described and relevant evidence is reviewed. According to the counter-regulation principle, attention is automatically allocated to information that is opposite in valence to current motivational states: A positive outcome focus increases the salience of negative information whereas a negative outcome focus induces an attentional focus on positive information. Counter-regulation in automatic affective processing prevents motivational states from escalating or becoming chronic. According to the control-dependency principle, processing of information is characterized by a problem focus (negativity bias) if goal pursuit is experienced as controllable, whereas experiencing a lack of control over important outcomes is accompanied by an enhancement focus (positivity bias). Control-dependency of affective processing promotes persistent goal pursuit in the face of controllable challenges, and facilitates the acceptance of a given situation and disengagement from blocked goals.
Intentions and Their Limits
Authors: von Suchodoletz Antje , Achtziger Anja
Published: January 2011

This paper discusses psychological approaches to intentions and to the limits of intentions and the biological foundations of intentions. Following a minimum common argument about what intentions are, psychological aspects of intentions are reviewed. We begin with a discussion of the developmental perspective on intentions. Then, the focus turns to the discussion of the limits of intentions, followed by the presentation of strategies that can help to overcome problems of goal setting and goal striving. Finally, different aspects of intentions are addressed, for instance, intentions as results of decisions after deliberation and as processes of conscious and unconscious goal striving.
Limits of the Conscious Control of Action
Authors: Schmitz Michael
Published: January 2011

After outlining why the notion of conscious control of action matters to us and after distinguishing different challenges to that notion, the contribution focuses on the challenge posed by the literature on unconscious goal pursuit. Based on a conceptual clarification of the notion of consciousness, I argue that the understanding of consciousness in that literature is too restricted. The possibility that the behaviors reported can be accounted for by nonconceptual forms of consciousness, such as emotions and motor experiences, rather than by – conscious or unconscious – conceptual level intentions tends to be disregarded, even though it promises to be empirically fruitful.
Evolution of deep‐water rifted margins: Testing depth‐dependent extensional models
Authors: Crosby A. G. , White N. J. , Edwards G. R. H. , Thompson M. , Corfield R. , Mackay L.
Published: January 2011

A general understanding of rifted margins, which form by thinning of the continental lithosphere, exists. Nevertheless, the exact form of thinning is unclear. This debate has been stimulated by acquisition of dense seismic wide‐angle and deep reflection surveys from Atlantic Ocean margins. A central issue concerns the way in which thinning changes with depth. We have tackled this issue by developing a generalized inverse model. This model attempts to fit subsidence and crustal thinning observations by varying strain rate as a function of time and space. Depth‐dependent thinning is permitted but we do not prescribe its existence or form. Here, the algorithm is applied to six margins, including two of the most contentious conjugate margins: Newfoundland‐Iberia and Brazil‐Angola. Calculated strain rate histories predict thinning estimates which broadly match estimates inferred from normal faulting. The Eastern Indian and Beaufort Sea margins formed by largely uniform lithospheric thinning. In contrast, the Newfoundland‐Iberian conjugate margins formed by a pattern of strongly depth‐dependent strain rate. To account for the paucity of syn‐rift decompression melting of the underlying asthenosphere, the lithospheric mantle close to oceanic‐continent transition must thin more slowly than the overlying crust. This form of depth dependency is not common. For example, the Brazil‐Angolan conjugate margin could have formed by uniform lithospheric thinning provided thick layers of salt were deposited in a preexisting 400 m deep topographic depression. Depth‐dependent thinning is not required to account for rapid subsidence of presalt strata.
Homeostatic defects in interleukin 18‐deficient mice contribute to protection against the lethal effects of endotoxin
Authors: Andrews Daniel M , Chow Melvyn T , Ma Yuting , Cotterell Claire L , Watt Sally V , Anthony Desiree A , Akira Shizuo , Iwakura Yoichiro , Trapani Joseph A , Zitvogel Laurence , Smyth Mark J
Published: January 2011

Toll‐like receptor‐4‐lipopolysaccharide (LPS)‐mediated inflammation is used to delineate signals involved in cross‐talk between antigen‐presenting cells (APCs) and lymphocytes such as natural killer (NK) cells. Following APC stimulation and cytokine release, NK cells produce interferon (IFN)‐γ. High levels of LPS induce endotoxicosis, a systemic inflammatory disease in which IFN‐γ causes significant morbidity and mortality. Several studies have highlighted the role of interleukin (IL)‐18, IL‐1β, IL‐17A and IFN‐γ in the development of endotoxicosis, but whether these cytokines interact with each other is yet to be determined. Our data demonstrate that IL‐18 and IL‐17A have important roles in NK cell IFN‐γ production during endotoxicosis. Importantly, we provide the first evidence that IL‐18 also has a role in IL‐17A production by T‐cell receptor (TCR)‐δ cells. Furthermore, we demonstrate that IL‐18‐deficient mice have a defect in γδ T‐cell homeostasis and IL‐1β production, both of which can contribute to the development of disease through induction of IL‐17A. These results reveal novel requirements for IL‐18 in innate immune cell homeostasis and activation, demonstrating that the role of IL‐18 in innate immunity occurs at a level other than activation.
BRIF and Variant Databases
Authors: Dalgleish Raymond
Published: January 2011

Databases of sequence variation in human genes (LSDBs) are an important resource for biology and medicine. Currently, the measurement of importance is not as objective as it might be and the establishment of impact factors would be of benefit to those who curate LSDBs. Specific issues relating to such databases are discussed.
Customer Relationship Management and Firm Performance
Authors: Coltman Tim , Devinney Timothy M , Midgley David F
Published: January 2011

In this paper, we examine the impact of customer relationship management (CRM) on firm performance using a hierarchical construct model. Following the resource-based view of the firm, strategic CRM is conceptualized as an endogenously determined function of the organization's ability to harness and orchestrate lower-order capabilities that comprise physical assets, such as IT infrastructure, and organizational capabilities, such as human analytics (HA) and business architecture (BA). Our results reveal a positive and significant path between a superior CRM capability and firm performance. In turn, superior CRM capability is positively associated with HA and BA. However, our results suggest that the impact of IT infrastructure on superior CRM capability is indirect and fully mediated by HA and BA. We also find that CRM initiatives jointly emphasizing customer intimacy and cost reduction outperform those taking a less balanced approach. Overall, this paper helps explain why some CRM programs are more successful than others and what capabilities are required to support success.
Measures of mixing quality in open flows with chaotic advection
Authors: Gouillart E. , Dauchot O. , Thiffeault J.-L.
Published: January 2011

We address the evaluation of mixing efficiency in experiments of chaotic mixing inside an open-flow channel. Since the open flow continuously brings new fluid into the limited mixing region, it is difficult to define relevant mixing indices as fluid particles experience typically very different stretching and mixing histories. The repeated stretching and folding of a spot of dye leads to a persistent pattern. We propose that the normalized standard deviation of this characteristic pattern is a good measure of the mixing quality of the flow. We discuss the link between this measure and mixing of continuously injected dye, and investigate it using an idealized map.
Periodic Ising Correlations
Authors: Hystad Grethe
Published: January 2011

In this paper, we first rework B. Kaufman's 1949 paper [Phys. Rev. 76, 1232 (1949)] by using representation theory. Our approach leads to a simpler and more direct way of deriving the spectrum of the transfer matrix for the finite periodic Ising model. We then determine formulas for the spin correlation functions that depend on the matrix elements of the induced rotation associated with the spin operator in a basis of eigenvectors for the transfer matrix. The representation of the spin matrix elements is obtained by considering the spin operator as an intertwining map. We exhibit the “new” elements \documentclass[12pt]{minimal}\begin{document}$V_{+}$\end{document}V+ and \documentclass[12pt]{minimal}\begin{document}$V_{-}$\end{document}V− in the Bugrij–Lisovyy formula [Phys. Lett. A 319, 390 (2003)] as part of a holomorphic factorization of the periodic and antiperiodic summability kernels on the spectral curve associated with the induced rotation for the transfer matrix.
Analysis of the HOOO torsional potential
Authors: Beames Joseph M. , Lester Marsha I. , Murray Craig , Varner Mychel E. , Stanton John F.
Published: January 2011

Torsional levels of cis and trans HOOO and DOOO, observed previously via infrared action spectroscopy [E. L. Derro, T. D. Sechler, C. Murray, and M. I. Lester, J. Chem. Phys. 128, 244313 (2008)10.1063/1.2945872], have been used in conjunction with ab initio theory to obtain a torsional potential energy surface for the hydrotrioxy radical. High level electronic structure calculations based on the equation-of-motion coupled-cluster method for ionized states (EOMIP-CCSD) are utilized to produce a torsional potential. Eigenvalues of the potential are computed by diagonalizing the torsional Hamiltonian in a free-rotor basis. Uniform scaling of the theoretical potential by a factor of 1.35 yields vibrational frequencies in good agreement with the experiment, and allows prediction of the barrier height to isomerization of ∼340 cm−1 and relative stability of trans-HOOO with respect to cis-HOOO of ∼70 cm−1. Examination of the optimized nuclear coordinates with respect to the torsional angle, suggests that the central O–O bond length is strongly coupled to the torsion and is important in determining the relative stabilities of the two conformers. The scaled potential is then used to determine the torsional contribution to the partition function for atmospheric modeling of HOOO.
Temperature and pressure dependence of secondary process in an epoxy system
Authors: Sharifi Soheil , Capaccioli Simone , Lucchesi Mauro , Rolla Pierangelo , Prevosto Daniele
Published: January 2011

Dielectric spectroscopy as a function of temperature and pressure was used to study the secondary relaxation in poly [(phenyl glycidyl ether)-co-formaldehyde] at hydrostatic pressure up to 600 MPa and at different temperatures between 315 and 243 K. From the analysis of the isothermal measurements, we observe that the activation volume of the secondary relaxation has nonmonotonic temperature dependence with a maximum at the temperature of the glass transition at ambient pressure. An interpretation in terms of mean hole volume dispersion is proposed based on literature data. Moreover, from isobaric data, we studied the effect of pressure on activation entropy and enthalpy of the secondary relaxation evidencing its local nature but also the presence of a certain complexity of the motion, which supports the idea that this process reflects the motion of a large part of the molecule.
A single-chip event sequencer and related microcontroller instrumentation for atomic physics research
Authors: Eyler E. E.
Published: January 2011

A 16-bit digital event sequencer with 50 ns resolution and 50 ns trigger jitter is implemented by using an internal 32-bit timer on a dsPIC30F4013 microcontroller, controlled by an easily modified program written in standard C. It can accommodate hundreds of output events, and adjacent events can be spaced as closely as 1.5 μs. The microcontroller has robust 5 V inputs and outputs, allowing a direct interface to common laboratory equipment and other electronics. A USB computer interface and a pair of analog ramp outputs can be added with just two additional chips. An optional display/keypad unit allows direct interaction with the sequencer without requiring an external computer. Minor additions also allow simple realizations of other complex instruments, including a precision high-voltage ramp generator for driving spectrum analyzers or piezoelectric positioners, and a low-cost proportional integral differential controller and lock-in amplifier for laser frequency stabilization with about 100 kHz bandwidth.
Evaluation of the performance of single root multireference coupled cluster method for ground and excited states, and its application to geometry optimization
Authors: Mahapatra Uttam Sinha , Chattopadhyay Sudip
Published: January 2011

The complete model space (CAS) based “genuine” single root multireference (MR) coupled cluster (sr-MRCC) method [Mahapatra and Chattopadhyay, J. Chem. Phys. 133, 074102 (2010)] has been extended to enable geometry optimizations by adopting the numerical gradient scheme. The sr-MRCC theory is designed to treat quasidegeneracies of varying degrees through the computation of essential static and dynamic correlation effects in a balanced way while bypassing the intruder states problem in a size-extensive manner. The efficacy of our sr-MRCC gradient approach has been illustrated by the optimization of the geometries of N2H2,CH2,C2H4,C4H4,O3 as well as trimethylenemethane (TMM) molecular systems, since such cases, by virtue of their complexity, warrant truly multireference description. We have explored the capability of the sr-MRCC approach to yield rotational energy surfaces for the ground and first singlet excited states of \documentclass[12pt]{minimal}\begin{document}${\rm N}_2{\rm H}_2$\end{document}N2H2. We also intend to explore the ground and the excited state energetics of some model systems (such as P4, H4, and \documentclass[12pt]{minimal}\begin{document}${\rm H}_8$\end{document}H8) for the computation of excitation energies by relying on the sr-MRCC method. An analysis of the results and a comparison with previous pertinent theoretical works including state specific MRCC (SS-MRCC) theory of Mukherjee and co-workers have also been presented. Although in most of the cases, we observe a close behavior between the sr-MRCC and SS-MRCC method, the error in the sr-MRCC is lower than the overall error of the SS-MRCC calculations in the vicinity of the transition region (manifesting a significant quasidegenerate character). The present results show that the sr-MRCC method and its numerical gradient variant are generally applicable to very demanding model and realistic chemical problems at acceptable accuracy and affordable computational expense which together attests the efficacy and viability of the sr-MRCC formalism for handling of static and dynamic correlations simultaneously thereby ensuring a balanced description for bond-breaking and other quasidegenerate situations with a various degree of MR character. Our preliminary results illustrate that our sr-MRCC method is a potential competitor for other state specific MRCC theories.
Binding structures of propylene glycol stereoisomers on the Si(001)−2×1 surface: A combined scanning tunneling microscopy and theoretical study
Authors: Hahn Jae Ryang , Bharath Satyaveda C. , Jeong Sukmin , Pearl Thomas P.
Published: January 2011

The binding configuration of propylene glycol stereoisomer molecules adsorbed on the Si(001)−2×1 surface was investigated using a combination of scanning tunneling microscopy (STM) and density functional theory calculations. Propylene glycol was found to adsorb dissociatively via two hydroxyl groups exclusively as a bridge between the ends of two adjacent dimers along the dimer row. The chirality was preserved during bonding to Si atoms and was identifiable with STM imaging. The large number of propylene glycol conformers in the gas phase was reduced to a single configuration adsorbed on the surface at low molecular coverage.
Correlations among residual multiparticle entropy, local atomic-level pressure, free volume and the phase-ordering rule in several liquids
Authors: Cao Qi-Long , Wang Wei-Lu , Li Y. D. , Liu C. S.
Published: January 2011

A modified Wang-Landau density-of-states sampling approach has been performed to calculate the excess entropy of liquid metals, Lennard-Jones (LJ) system and liquid Si under NVT conditions; and it is then the residual multiparticle entropy (SRMPE) is obtained by subtraction of the pair correlation entropy. The temperature dependence of SRMPE has been investigated along with the temperature dependence of the local atomic-level pressure and the pair correlation functions. Our results suggest that the temperature dependence of the pair correlation entropy is well described by T−1 scaling while T−0.4 scaling well describes the relationship between the excess entropy and temperature. For liquid metals and LJ system, the -SRMPE versus temperature curves show positive correlations and the -SRMPE of liquid Si is shown to have a negative correlation with temperature, the phase-ordering criterion (based on the SRMPE) for predicting freezing transition works in liquid metals and LJ but fails in liquid Si. The local atomic-level pressure scaled with the virial pressure ($\sigma_{al}/\sigma_{av}$σal/σav) exhibits the much similar temperature dependence as -SRMPE for all studied systems, even though simple liquid metals and liquid Si exhibit opposite temperature dependence in both $\sigma_{al}/\sigma_{av}$σal/σav and -SRMPE. The further analysis shows that the competing properties of the two effects due to localization and free volume on the SRMPE exist in simple liquid metals and LJ system but disappear in liquid Si, which may be the critical reason of the failure of the phase-ordering criterion in liquid Si.
Synthetic cation-selective nanotube: Permeant cations chaperoned by anions
Authors: Hilder Tamsyn A. , Gordon Dan , Chung Shin-Ho
Published: January 2011

The ability to design ion-selective, synthetic nanotubes which mimic biological ion channels may have significant implications for the future treatment of bacteria, diseases, and as ultrasensitive biosensors. We present the design of a synthetic nanotube made from carbon atoms that selectively allows monovalent cations to move across and rejects all anions. The cation-selective nanotube mimics some of the salient properties of biological ion channels. Before practical nanodevices are successfully fabricated it is vital that proof-of-concept computational studies are performed. With this in mind we use molecular and stochastic dynamics simulations to characterize the dynamics of ion permeation across a single-walled (10, 10), 36 Å long, carbon nanotube terminated with carboxylic acid with an effective radius of 5.08 Å. Although cations encounter a high energy barrier of 7 kT, its height is drastically reduced by a chloride ion in the nanotube. The presence of a chloride ion near the pore entrance thus enables a cation to enter the pore and, once in the pore, it is chaperoned by the resident counterion across the narrow pore. The moment the chaperoned cation transits the pore, the counterion moves back to the entrance to ferry another ion. The synthetic nanotube has a high sodium conductance of 124 pS and shows linear current-voltage and current-concentration profiles. The cation-anion selectivity ratio ranges from 8 to 25, depending on the ionic concentrations in the reservoirs.
Raman study of low-frequency modes in three glycine polymorphs
Authors: Surovtsev N. V. , Malinovsky V. K. , Boldyreva E. V.
Published: January 2011

The temperature dependence of selected low-wavenumber (< 200 cm−1) Raman bands was studied for the different crystalline phases (α-, β-, γ-) of glycine — the simplest possible “building block” of a biomolecule. The temperature dependence of the frequencies of vibrational modes deviates from the theoretical expectation based on the assumption of cubic anharmonicity. Although relatively small, this deviation was observed above 250 K for all the three polymorphs. This finding was discussed in relation to the “dynamical transition” phenomenon, observed in variety of biomolecules in the range 200–250 K. The similarity of the temperatures suggests, that the origin of the dynamical transition phenomenon can be related to intrinsic conformational states of biomolecules, while water serves rather as a plasticizer or a structure organizer.
Order parameters for macromolecules: Application to multiscale simulation
Authors: Singharoy A. , Cheluvaraja S. , Ortoleva P.
Published: January 2011

Order parameters (OPs) characterizing the nanoscale features of macromolecules are presented. They are generated in a general fashion so that they do not need to be redesigned with each new application. They evolve on time scales much longer than 10−14 s typical for individual atomic collisions/vibrations. The list of OPs can be automatically increased, and completeness can be determined via a correlation analysis. They serve as the basis of a multiscale analysis that starts with the N-atom Liouville equation and yields rigorous Smoluchowski/Langevin equations of stochastic OP dynamics. Such OPs and the multiscale analysis imply computational algorithms that we demonstrate in an application to ribonucleic acid structural dynamics for 50 ns.
A polarizable ion model for the structure of molten CuI
Authors: Bitrián Vicente , Alcaraz Olga , Trullàs Joaquim
Published: January 2011

The results are reported of the molecular dynamics simulations of the coherent static structure factor of molten CuI at 938 K using a polarizable ion model. This model is based on a rigid ion potential to which the many body interactions due to the anions induced polarization are added. The calculated structure factor reproduces the clear sharp prepeak observed in neutron diffraction data. The corresponding partial structure factors and the related radial distribution functions calculated by molecular dynamics are compared with those found in the literature derived from a combination of neutron and x-ray diffraction data with the aid of the reverse Monte Carlo simulation technique, as well as those calculated by ab initio MD simulations.
Effects of finite size nuclei in relativistic four-component calculations of hyperfine structure
Authors: Malkin Elena , Repiský Michal , Komorovský Stanislav , Mach Pavel , Malkina Olga L. , Malkin Vladimir G.
Published: January 2011

The effect of a finite size model for both the nuclear charge and magnetic moment distributions on calculated EPR hyperfine structure have been studied using a relativistic four-component method based on density functional theory. This approach employs a restricted kinetically balanced basis (mDKS-RKB) and includes spin-polarization using noncollinear spin-density exchange-correlation functionals in the unrestricted fashion. Benchmark calculations have been carried out for a number of small molecules containing Zn, Cd, Ag, and Hg. The present results are compared with those obtained at the Douglas–Kroll–Hess second order (DKH-2) method. The dependence of the results on the quality of the orbital and auxiliary basis sets has been studied. It was found that some basis sets contain irregularities that deteriorate the results. Especial care has to be taken also on the construction of the auxiliary basis for fitting the total electron and spin-densities.
Long-time growth kinetics of first order phase transitions in the presence of a boundary layer
Authors: Mitra Mithun K. , Muthukumar M.
Published: January 2011

The late stage growth mechanism for a first order phase transition, either through nucleation growth or spinodal decomposition, is well understood to be an Ostwald ripening or coarsening process, in which larger domains grow at the expense of smaller ones. The growth kinetics in this regime was shown by Lifshitz and Slyozov to follow a \documentclass[12pt]{minimal}\begin{document}$t^{1/3}$\end{document}t1/3 law. However, the kinetics is altered if there exists a barrier ahead of the growth front, irrespective of the physical origin of the boundary layer. We present an analytic calculation for the growth kinetics in the presence of a boundary layer, showing that in the limit of barrier-dominated growth, the domains grow with a \documentclass[12pt]{minimal}\begin{document}$t^{1/2}$\end{document}t1/2 law. This result holds true in the dilute regime independent of whether the growing nuclei are spherical or cylindrical.
Ionic solvation studied by image-charge reaction field method
Authors: Lin Yuchun , Baumketner Andrij , Song Wei , Deng Shaozhong , Jacobs Donald , Cai Wei
Published: January 2011

In a preceding paper [J. Chem. Phys. 131, 154103 (2009)], we introduced a new, hybrid explicit/implicit method to treat electrostatic interactions in computer simulations, and tested its performance for liquid water. In this paper, we report further tests of this method, termed the image-charge solvation model (ICSM), in simulations of ions solvated in water. We find that our model can faithfully reproduce known solvation properties of sodium and chloride ions. The charging free energy of a single sodium ion is in excellent agreement with the estimates by other electrostatics methods, while offering much lower finite-size errors. Similarly, the potentials of mean force computed for Na–Cl, Na–Na, and Cl–Cl pairs closely reproduce those reported previously. Collectively, our results demonstrate the superior accuracy of the proposed ICSM method for simulations of mixed media.
Sampling the structure of calcium carbonate nanoparticles with metadynamics
Authors: Quigley D. , Freeman C. L. , Harding J. H. , Rodger P. M.
Published: January 2011

Metadynamics is employed to sample the configurations available to calcium carbonate nanoparticles in water, and to map an approximate free energy as a function of crystalline order. These data are used to investigate the validity of bulk and ideal surface energies in predicting structure at the nanoscale. Results indicate that such predictions can determine the structure and morphology of particles as small as 3–4 nm in diameter. Comparisons are made to earlier results on 2 nm particles under constant volume conditions which support nanoconfinement as a mechanism for enhancing the stability of amorphous calcium carbonate. Our results indicate that crystalline calcitelike structure is thermodynamically preferred for nanoparticles as small as 2 nm in the absence of nanoconfinement.
Complex phase behavior of a fluid in slits with semipermeable walls modified with tethered chains
Authors: Borówko M. , Patrykiejew A. , Rżysko W. , Sokołowski S. , Ilnytskyi J.
Published: January 2011

We study the phase behavior of a two-component fluid in a pore with the walls modified by tethered chains. The walls are completely permeable for one component of the fluid and completely impenetrable for the second component. The fluid is perfectly mixed in a bulk phase. We have found that depending on the details of the model the fluid undergoes capillary condensation inside the pore and wetting and layering transitions at the outer walls. Moreover, we have found transitions connected with the change of symmetry of the distribution of chains and fluid inside the pore.
Thermodynamical approach to sympathetic cooling of neutral particles
Authors: Borisenok Sergey , Rozhdestvensky Yuri
Published: January 2011

We present a “toy” classical model for sympathetic cooling of the neutral Brownian particle in the frame of robust thermodynamical approach. The cooling time is expressed with the parameters of the Brownian particle and the particles from the cooling reservoir. Qualitative and numerical estimations of the model confirm that the sympathetic cooling can be efficient for heavy neutral molecules and clusters.
Vibrational interference effects in x-ray emission of a model water dimer: Implications for the interpretation of the liquid spectrum
Authors: Ljungberg M. P. , Pettersson L. G. M. , Nilsson A.
Published: January 2011

We apply the Kramers–Heisenberg formula to a model water dimer to discuss vibrational interference in the x-ray emission spectrum of the donor molecule for which the core-ionized potential energy surface is dissociative but bounded by the accepting molecule. A long core–hole lifetime leads to decay from Zundel-like, fully delocalized vibrational states in the intermediate potential without involvement of a specific dissociated component. Comparison is made to a model with an unbound intermediate state allowing dissociation to infinity which gives a sharp, fully dissociated feature, and a broad molecular peak at long core–hole life time. The implications of the vibrational interference effect on the liquid water spectrum are discussed and it is proposed that this mainly gives rise to an isotope-dependent asymmetrical broadening of the lone pair peak.
Watching bismuth nanowires grow
Authors: Ham Jinhee , Shim Wooyoung , Kim Do Hyun , Oh Kyu Hwan , Voorhees Peter W. , Lee Wooyoung
Published: January 2011

We report real-time high temperature scanning electron microscopy observations of the growth of bismuth nanowires via the on-film formation of nanowires (OFF-ON) method. These observations provide experimental evidence that thermally induced-stress on a Bi film is the driving force for the growth of Bi nanowires with high aspect ratios, uniform diameter, and high-quality crystallinity. Our results show that immobile grain boundaries in the Bi film are required for the growth of nanowires so that grain broadening resulting in hillock formation can be prevented. This study not only provides an understanding of the underlying mechanism, but also affords a strategy for facilitating nanowire growth by OFF-ON.
Low spin current-driven dynamic excitations and metastability in spin-valve nanocontacts with unpinned artificial antiferromagnet
Authors: Eggeling M. , Dimopoulos T. , Uhrmann T. , Bethge O. , Heer R. , Höink V. , Brückl H.
Published: January 2011

This work investigates the spin-torque-related dynamics of nonuniform magnetic vortexlike states in spin-valve nanocontacts, employing an unpinned artificial antiferromagnet as polarizer and amorphous CoFeB as free layer. Subgigahertz spectra are obtained for contacts of 150–200 nm in diameter. Low critical current density and reversibility of the dynamic spectra with respect to the current are obtained. The spectral power and linewidth depend on the in-plane magnetic field, assuming maximum, respectively minimum, values within the free layer’s magnetization switching. For certain field and current windows metastable dynamic states are clearly demonstrated.
Understanding electroforming in bipolar resistive switching oxides
Authors: Gomez-Marlasca F. , Ghenzi N. , Rozenberg M. J. , Levy P.
Published: January 2011

We study electroforming on the resistive switching (RS) behavior of silver-manganite interfaces. Using the technique of hysteresis switching loops we define an electroforming procedure that enables us to study its influence on the RS behavior in a systematic manner. We show that two similar electroforming procedures may lead to either RS or no RS at all. We explain the observed behavior by associating the forming procedure and the memory switching operation to major and minor hysteresis loops, respectively. With the obtained insight we propose a simple and nearly optimal electroforming procedure.
Nonlinear amplification and mixing of spin waves in a microstrip geometry with metallic ferromagnets
Authors: Khivintsev Yuri , Marsh J. , Zagorodnii V. , Harward I. , Lovejoy J. , Krivosik P. , Camley R. E. , Celinski Z.
Published: January 2011

We explore the nonlinear mixing and amplification of magnetic polariton modes in ultrasmall waveguides. Ultrasmall waveguide geometries can produce large oscillating microwave fields—up to about 500 Oe. Using these large fields, we examine nonlinear ferromagnetic dynamics in ribbons of Permalloy and Fe. In particular if two microwave signals at different frequencies are sent into the waveguide, we can increase the transmission of one wave by adding energy to the other wave. We also demonstrate the creation of new frequencies and the development of a comb of equally spaced frequencies. These experimental results are explained with perturbation theory and micromagnetics calculations.
Wall energy relaxation in the Cahn–Hilliard model for moving contact lines
Authors: Yue Pengtao , Feng James J.
Published: January 2011

The Cahn–Hilliard model uses diffusion between fluid components to regularize the stress singularity at a moving contact line. In addition, it represents the dynamics of the near-wall layer by the relaxation of a wall energy. The first part of the paper elucidates the role of the wall relaxation in a flowing system, with two main results. First, we show that wall energy relaxation produces a dynamic contact angle that deviates from the static one, and derive an analytical formula for the deviation. Second, we demonstrate that wall relaxation competes with Cahn–Hilliard diffusion in defining the apparent contact angle, the former tending to “rotate” the interface at the contact line while the latter to “bend” it in the bulk. Thus, varying the two in coordination may compensate each other to produce the same macroscopic solution that is insensitive to the microscopic dynamics of the contact line. The second part of the paper exploits this competition to develop a computational strategy for simulating realistic flows with microscopic slip length at a reduced cost. This consists in computing a moving contact line with a diffusion length larger than the real slip length, but using the wall relaxation to correct the solution to that corresponding to the small slip length. We derive an analytical criterion for the required amount of wall relaxation, and validate it by numerical results on dynamic wetting in capillary tubes and drop spreading.