bluuebunny/crossref_metadata_2025 huggingface dataset:
The loess cover of northeastern Wisconsin
Authors: Schaetzl Randall J. , Attig John W.
Published: January 2013

We present the first study of the distribution, genesis and paleoenvironmental significance of late Pleistocene loess in northeastern Wisconsin and adjacent parts of Michigan's Upper Peninsula. Loess here is commonly 25–70 cm thick. Upland areas that were deglaciated early and remained geomorphically stable preferentially accumulated loess by providing sites that were efficient at trapping and retaining eolian sediment. Data from 419 such sites indicate that the loess was mainly derived from proglacial outwash plains and to a lesser extent, hummocky end moraines within and near the region, particularly those toward the east of the loess deposits. Most of the loess was transported on katabatic winds coming off the ice sheet, which entrained and transported both silt and fine sands. The loess fines markedly, and is better sorted, distal to these source regions. Only minimal amounts of loess were deposited in this area via westerly winds. This research (1) reinforces the observation that outwash plains and end moraines can be significant loess sources, (2) provides evidence for katabatic winds as significant eolian transport vectors, and (3) demonstrates that the loess record may be variously preserved across landscapes, depending on where and when geomorphically stable sites became available for loess accumulation.
Does Use of Nicotine Replacement Therapy While Continuing to Smoke Undermine Cessation?: A Systematic Review
Authors: Beard Emma , Aveyard Paul , Michie Susan , McNeill Ann , West Robert
Published: January 2013

Aims: To review population surveys to assess (a) prevalence of the use of NRT for smoking reduction (SR) and temporary abstinence (TA) and (b) how far this is associated with attempts to stop smoking, smoking cessation and reduction in cigarette consumption.

Methods: An electronic search was undertaken of EMBASE, MEDLINE, Web of Science and PsycINFO. Articles were selected if they (1) assessed whether smokers had used or were currently using NRT for SR and/or TA; (2) involved smokers who had not taken part in a harm reduction programme; and (3) assessed prevalence and/or association of SR and/or TA with reductions in cigarette consumption and/or attempts to stop smoking and/or with smoking cessation. Twelve studies met the inclusion criteria and results were extracted independently by two researchers.

Results: Data were available from five countries (US, UK, Canada, Switzerland and Australia). Between 1% and 23% of smokers reported having ever used NRT for smoking reduction and between 2% and 14% during periods of temporary abstinence. Use of NRT for SR and/or TA was associated with little or no reduction in cigarette consumption. There was some evidence that it was positively associated with attempts to stop smoking and smoking cessation.

Conclusion: In smoking populations use of NRT to aid SR and in situations where smoking is not permitted appears to be having little effect on achieving a reduction in cigarette consumption but does not undermine cessation and may promote it.
International Law and Public Attitudes Toward Torture: An Experimental Study
Authors: Wallace Geoffrey P.R.
Published: January 2013

Domestic approaches to compliance with international commitments often presume that international law has a distinct effect on the beliefs and preferences of national publics. Studies attempting to estimate the consequences of international law unfortunately face a wide range of empirical and methodological challenges. This article uses an experimental design embedded in two U.S. national surveys to offer direct systematic evidence of international law's effect on mass attitudes. To provide a relatively tough test for international law, the surveys examine public attitudes toward the use of torture, an issue in which national security concerns are often considered paramount. Contrary to the common contention of international law's inefficacy, I find that legal commitments have a discernible impact on public support for the use of torture. The effect of international law is also strongest in those contexts where pressures to resort to torture are at their highest. However, the effects of different dimensions in the level of international agreements' legalization are far from uniform. In contrast to the attention often devoted to binding rules, I find that the level of obligation seems to make little difference on public attitudes toward torture. Rather, the relative precision of the rules, along with the degree to which enforcement is delegated to third parties, plays a much greater role in shaping public preferences. Across both international law and legalization, an individual's political ideology also exerts a strong mediating effect, though in varying directions depending on the design of the agreement. The findings have implications for understanding the overall impact of international law on domestic actors, the importance of institutional design, and the role of political ideology on compliance with international agreements.
Authoritarian Signaling, Mass Audiences, and Nationalist Protest in China
Authors: Weiss Jessica Chen
Published: January 2013

How can authoritarian states credibly signal their intentions in international crises? Nationalist, antiforeign protests are one mechanism by which authoritarian leaders can visibly demonstrate their domestic vulnerability. Because protests in authoritarian states are risky and costly to repress, the decision to allow or stifle popular mobilization is informative. The threat of instability demonstrates resolve, and the cost of concession increases the credibility of a tough stance. The danger of instability and escalation increases foreign incentives to make concessions and preserve the status quo. This logic helps explain the pattern of authoritarian tolerance and repression toward nationalist protest. A case study of two U.S.-China crises shows how China's management of anti-American protests affected U.S. beliefs about Chinese resolve.
Derivation of radial electric fields using kinetic theory in tokamak
Authors: NOORI K. , KHORSHID P. , AFSARI M.
Published: January 2013

In the current study, radial electric field with fluid equations has been calculated. The calculation started with kinetic theory, Boltzmann and momentum balance equations were derived, the negligible terms compared with others were eliminated, and the radial electric field expression in steady state was derived. As mentioned in previous researches, this expression includes all types of particles such as electrons, ions, and neutrals. The consequence of this solution reveals that three major driving forces contribute in radial electric field: radial pressure gradient, poloidal rotation, and toroidal rotation; rotational terms mean Lorentz force. Therefore, radial electric field and plasma rotation are connected through the radial momentum balance.
The scaling of reconnection rate in the two-fluid model of a collisionless forced magnetic reconnection
Authors: HOSSEINPOUR M.
Published: January 2013

The two-fluid model of collisionless forced magnetic reconnection is considered where breaking the frozen-in flow constraint for magnetic field lines is provided by electron inertia. Following the Taylor problem, a tearing stable slab of plasma with a magnetic field reversal is subjected to a small-amplitude boundary perturbation that drives magnetic reconnection at the neutral surface within the plasma. It has been shown that unlike the resistive regime, where the two-fluid magnetohydrodynamics (MHD) description reduces to the single-fluid MHD regime at sufficiently small values of the ion inertial skin-depth, di ≡ c/ωpi (with ωpi as the ion plasma frequency), there is no room for the single-fluid MHD reconnection in the collisionless case, even at very small values of di. Meanwhile, contradictory to the resistive reconnection, the rate of collisionless Hall reconnection always decreases with time as reconnection proceeds. In particular, in the main stage of Hall reconnection, when transition between two main equilibria states are taking place, it scales as t−1/2.
XX.—The Meteorology of Edinburgh
Authors: Mossman Robert Cockburn
Published: January 2013

Since the foundation of the Scottish Meteorological Society in 1856, a mass of information regarding the climate of Edinburgh has been reduced and published in the Society's Journal from time to time, the data being furnished to that body by its local observers. In addition, numerous unreduced manuscript books of meteorological observations which extend back to the year 1764 are further available for discussion. In 1861 the late Principal Forbes communicated to this Society a paper on the “Climate of Edinburgh,” two elements of climate being alone discussed, viz., temperature and rainfall, and for a period of but forty years. The reduction of the observations taken virtually without a break during the past 132 years was therefore desirable for the discussion of cyclical and other weather changes, for which records covering a long period are absolutely necessary. Through the kindness of the Councils of the Scottish Meteorological Society, the Royal Society of Edinburgh, and the Royal Meteorological Society, the loan of the manuscript registers kept in Edinburgh and its immediate vicinity was obtained.
Explaining Moral Variety
Authors: Kukathas Chandran
Published: January 2013

Reflection on the variety of forms of social life has long been a source of moral skepticism. The thought that there are many radically different social systems, each of which colors the way its members think about moral and political questions, has been thought by many moral philosophers to undermine confidence in our belief that our way of looking at-or even posing-these questions is the correct one. The fact of cultural variety is held to reduce, if not eliminate altogether, the possibility of moral criticism of the practices of other societies. This thought is not a recent one; it is implicit, for example, in an observation made in David Hume's “A Dialogue,” when he writes:

There are no manners so innocent or reasonable, but may be rendered odious or ridiculous, if measured by a standard, unknown to the persons; especially, if you employ a little art or eloquence, in aggravating some circumstances, and extenuating others, as best suits the purpose of your discourse.
NONPARAMETRIC INFERENCE FOR CONDITIONAL QUANTILES OF TIME SERIES
Authors: Xu Ke-Li
Published: January 2013

This paper considers model-free hypothesis testing and confidence interval construction for conditional quantiles of time series. A new method, which is based on inversion of the smoothed empirical likelihood of the conditional distribution function around the local polynomial estimator, is proposed. The associated inferential procedures do not require variance estimation, and the confidence intervals are automatically shaped by data. We also construct the bias-corrected empirical likelihood, which does not require undersmoothing. Limit theories are developed for mixing time series. Simulations show that the proposed methods work well in finite samples and outperform the normal confidence interval. An empirical application to inference of the conditional value-at-risk of stock returns is also provided.
ESTIMATION OF AND INFERENCE ABOUT THE EXPECTED SHORTFALL FOR TIME SERIES WITH INFINITE VARIANCE
Authors: Linton Oliver , Xiao Zhijie
Published: January 2013

We study estimation and inference of the expected shortfall for time series with infinite variance. Both the smoothed and nonsmoothed estimators are investigated. The rate of convergence is determined by the tail thickness parameter, and the limiting distribution is in the stable class with parameters depending on the tail thickness parameter of the time series and on the dependence structure, which makes inference complicated. A subsampling procedure is proposed to carry out statistical inference. We also analyze a nonparametric estimator of the conditional expected shortfall. A Monte Carlo experiment is conducted to evaluate the finite sample performance of the proposed inference procedure, and an empirical application to emerging market exchange rates (from October 1997 to October 2008) is conducted to highlight the proposed study.
Average Frobenius distribution for the degree two primes of a number field
Authors: JAMES KEVIN , SMITH ETHAN
Published: January 2013

Let K be a number field and r an integer. Given an elliptic curve E, defined over K, we consider the problem of counting the number of degree two prime ideals of K with trace of Frobenius equal to r. Under certain restrictions on K, we show that “on average” the number of such prime ideals with norm less than or equal to x satisfies an asymptotic identity that is in accordance with standard heuristics. This work is related to the classical Lang–Trotter conjecture and extends the work of several authors.
Sur les solutions friables de l'équation a+b=c
Authors: DRAPPEAU SARY
Published: January 2013

In a recent paper [5], Lagarias and Soundararajan study the y-smooth solutions to the equation a+b=c. Conditionally under the Generalised Riemann Hypothesis, they obtain an estimate for the number of those solutions weighted by a compactly supported smooth function, as well as a lower bound for the number of bounded unweighted solutions. In this paper, we prove a more precise conditional estimate for the number of weighted solutions that is valid when y is relatively large with respect to x, so as to connect our estimate with the one obtained by La Bretèche and Granville in a recent work [2]. We also prove, conditionally under the Generalised Riemann Hypothesis, the conjectured upper bound for the number of bounded unweighted solutions, thus obtaining its exact asymptotic behaviour.
The space of immersed surfaces in a manifold
Authors: RANDAL–WILLIAMS OSCAR
Published: January 2013

We study the cohomology of the space of immersed genusgsurfaces in a simply-connected manifold. We compute the rational cohomology of this space in a stable range which goes to infinity withg. In fact, in this stable range we are also able to obtain information about torsion in the cohomology of this space, as long as we localise away from (g-1).
17th ICOMOS General Assembly, Paris, France
Authors: Naeem Anila
Published: January 2013

The 17th General Assembly of the International Council on Monuments and Sites (ICOMOS) took place at the UNESCO Headquarters, Paris (France), from 27 November to 2 December 2011, under the high patronage of Irina Bokova, Director General of UNESCO, and Nicolas Sarkozy, President of the French Republic. The events included meetings of the Advisory and Executive Committees, the Scientific Council, International Scientific Committees (ISCs); the Scientific Symposium; and the General Assembly. According to the ICOMOS official report, this conference had a record attendance of 1200 registered participants, representing 106 countries and 77 National Committees. The generous grants offered to National Committees through the ICOMOS Victoria Falls Fund and the Getty Foundation made it possible for 63 professionals from 47 countries to attend the event.
Expert Meeting on the 20th Anniversary of UNESCO's Memory of the World Programme
Authors: Shyllon Folarin
Published: January 2013

The meeting of experts in Warsaw is one of the activities marking the 20th anniversary of the Memory of the World (MoW) program. The events started on 1 April and were held throughout 2012, including a MoW Exhibition at the UNESCO headquarters that focused on items that are listed on MoW Register (national, regional, and international) and an international conference held 26–28 September 2012 in Vancouver, Canada, on Memory of the World in the Digital Age: Digitization and Preservation. The challenges and solutions relating to the impact of the technological advances for the preservation and accessibility of the documentary heritage have occupied the attention of UNESCO for some time, culminating in the adoption of the Charter on the Preservation of the Digital Heritage by the 32nd session of the General Conference of UNESCO on 17 October 2003.
The International Law of Culture: Prospects and Challenges
Authors: Burri Mira
Published: January 2013

The international law of culture is a broad field, which certainly goes beyond the United Nations Educational, Social and Cultural Organization (UNESCO), as the international organization entrusted with, among other things, cultural affairs. Indeed, if one considers the far-reaching definition of culture, then a vast number of institutions, rules of hard and soft law, and initiatives of different scope and shape exist, and new ones come into being. This institutional complexity and the ensuing rule fragmentation are indicative of multiple scenes of contestation, denoted by different actors, politics, dynamics, and often strong path dependencies, which make meaningful communication between them and a solution-oriented forward thinking difficult. In scholarship, too, there appears to be increasing specialization, which carves out topics and subtopics, such as the UNESCO versus the World Trade Organization (WTO) clash, cultural heritage preservation, or indigenous peoples' rights. This may, despite the deeper knowledge won, hinder pinpointing appropriate regulatory responses at the international level, which could address cultural rights comprehensively.
Second Meeting of the States Parties to the 1970 UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property
Authors: Shyllon Folarin
Published: January 2013

The UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property was adopted in Paris on 14 November 1970. It came into force on 24 April 1972. It took over 30 years for the first Meeting of States Parties to the Convention to take place on 15 October 2003. The second meeting, the subject of this report, took place after a shorter period of about nine years, on 20–21 June 2012. A Meeting of States Parties to a treaty is primarily a forum to discuss and agree on measures that can be taken to improve its effectiveness and the realization of the aims and objectives of the instrument. Accordingly, the meeting was tasked with examining in depth the impact of the measures taken by States Parties to the Convention in order to optimize its implementation, and also to consider and approve whatever efficacious measures should be taken for its best functioning.
Valuing marine parks in a small island developing state: a travel cost analysis in Seychelles
Authors: Mwebaze Paul , MacLeod Alan
Published: January 2013

A major problem facing the Seychelles islands is the decline in the quality and the value of marine protected areas (MPAs). Economic valuation can help guide policy makers to understand the value of marine resources and the cost of neglecting MPAs by expressing the value of their goods and services in monetary terms. This paper presents an analysis of the economic value of a group of marine parks in Seychelles. The travel cost method is used to establish willingness-to-pay of international tourists for trips to marine parks in Seychelles from their observed behaviour. The average per-trip consumer surplus is approximately €128 for single-site visitors and €65 for multiple-site visitors. The total social welfare value attributable to the recreational opportunity in marine parks is approximately €3.7 million annually. These results provide policy makers with a strong justification for government investment needed to maintain marine sites in Seychelles.
Clostridium difficilein foods and animals: history and measures to reduce exposure
Authors: Rodriguez-Palacios Alex , Borgmann Stefan , Kline Terence R. , LeJeune Jeffrey T.
Published: January 2013

Many articles have summarized the changing epidemiology ofClostridium difficileinfections (CDI) in humans, but the emerging presence ofC. difficilein foods and animals and possible measures to reduce human exposure to this important pathogen have been infrequently addressed. CDIs have traditionally been assumed to be restricted to health-care settings. However, recent molecular studies indicate that this is no longer the case; animals and foods might be involved in the changing epidemiology of CDIs in humans; and genome sequencing is disproving person-to-person transmission in hospitals. Although zoonotic and foodborne transmission have not been confirmed, it is evident that susceptible people can be inadvertently exposed toC. difficilefrom foods, animals, or their environment. Strains of epidemic clones present in humans are common in companion and food animals, raw meats, poultry products, vegetables, and ready-to-eat foods, including salads. In order to develop science-based prevention strategies, it is critical to understand howC. difficilereaches foods and humans. This review contextualizes the current understanding of CDIs in humans, animals, and foods. Based on available information, we propose a list of educational measures that could reduce the exposure of susceptible people toC. difficile. Enhanced educational efforts and behavior change targeting medical and non-medical personnel are needed.
Organic grain cropping systems to enhance ecosystem services
Authors: Cavigelli Michel A. , Mirsky Steven B. , Teasdale John R. , Spargo John T. , Doran John
Published: January 2013

Organic grain cropping systems can enhance a number of ecosystem services compared with conventional tilled (CT) systems. Recent results from a limited number of long-term agricultural research (LTAR) studies suggest that organic grain cropping systems can also increase several ecosystem services relative to conventional no-till (NT) cropping systems: soil C sequestration and soil N fertility (N mineralization potential) can be greater while global warming potential (GWP) can be lower in organic systems that use animal manures and cover crops compared with conventional NT systems. However, soil erosion from organic systems and nitrous oxide (N2O, a greenhouse gas) emissions from manure-based organic systems appear to be greater than from conventional NT systems, though data are limited. Also, crop yields, on average, continue to be lower and labor requirements greater in organic than in both tilled and NT conventional systems. Ecosystem services provided by organic systems may be improved by expanding crop rotations to include greater crop phenological diversity, improving nutrient management, and reducing tillage intensity and frequency. More diverse crop rotations, especially those that include perennial forages, can reduce weed pressure, economic risk, soil erosion, N2O emissions, animal manure inputs, and soil P loading, while increasing grain yield and soil fertility. Side-dressing animal manures in organic systems may increase corn nitrogen use efficiency and also minimize animal manure inputs. Management practices that reduce tillage frequency and intensity in organic systems are being developed to reduce soil erosion and labor and energy needs. On-going research promises to further augment ecosystem services provided by organic grain cropping systems.
OUTCOME LEVEL ANALYSIS OF BELIEF CONTRACTION
Authors: HANSSON SVEN OVE
Published: January 2013

The outcome set of a belief change operator is the set of outcomes that can be obtained with it. Axiomatic characterizations are reported for the outcome sets of the standard AGM contraction operators and eight types of base-generated contraction. These results throw new light on the properties of some of these operators.
Die Symptomstruktur des BDI-II: Kernsymptome und qualitative Facetten
Authors: Bühler Joël , Keller Ferdinand , Läge Damian
Published: January 2013

Theoretischer Hintergrund: Das BDI-II deckt mit 21 Depressionssymptomen die Breite der Depression ab und ist geeignet, die Symptomstruktur der Depression zu erforschen. Eine Vielzahl an faktorenanalytischen Studien erbrachte aber bislang keinen Konsens. Fragestellung: Nonmetrische Multidimensionale Skalierung (NMDS) soll daher die divergierenden Resultate einordnen und ein Modell der Symptomstruktur schaffen. Methode: Mittels NMDS wird die Symptomstruktur des BDI‐II (N = 266 Depressive) in einen 2‐dimensionalen Raum abgebildet. Ergebnisse: Die NMDS‐Lösung legt eine Facettenstruktur nahe, welche von den faktorenanalytischen Modellen bislang unzulänglich erfasst wird. Schlussfolgerungen: Neben einem generellen Kernsyndrom finden sich fünf spezifische Facetten (verminderte Aktivierung, psychovegetative Symptome, gesteigerte Aktivierung, Hoffnungslosigkeit und negative Einstellung zum Selbst), die die Heterogenität der Symptomatik innerhalb der Depression aufzeigen und damit die Existenz von Subtypen in der Depression nahelegen.
Chronische Alpträume: Wirksamkeit eines deutschsprachigen Manuals zur angeleiteten Selbsthilfe mit Imagery Rehearsal Therapy
Authors: Kröner Tana , Hansen Kathrin , Steil Regina
Published: January 2013

Theoretischer Hintergrund: Chronische Alpträume stellen eine weit verbreitete Schlafstörung dar, welche einen hohen Leidensdruck hervorruft. Als besonders wirksam in der Behandlung gilt die Imagery Rehearsal Therapy (IRT). Selbsthilfeprogramme stellen hierbei eine effektive, ökonomische Behandlungsoption dar. Fragestellung: Die vorliegende Pilotstudie untersucht die Wirksamkeit einer neuen, IRT-basierten, angeleiteten Selbsthilfe. Methode: 10 Patienten mit chronischen Alpträumen wurden im Rahmen von 4 face-to-face-Sitzungen vor Intervention (T1) sowie 4 Wochen (T2) und 3 Monate (T3) danach hinsichtlich Alptraumhäufigkeit sowie verschiedener psychosozialer Parameter untersucht. Ergebnisse: Die Alptraumhäufigkeit reduzierte sich innerhalb von 4 Wochen signifikant (T1-T2; Effektstärke: 1,0). Dieser Effekt blieb über 3 Monate stabil (T1-T3; Effektstärke: 1,26). Zudem reduzierten sich signifikant Depressions-, Angst- und Anspannungsparameter sowie das Stresserleben. Schlussfolgerung: Das deutschsprachige Selbsthilfemanual könnte eine wirksame Behandlungsmöglichkeit zur Reduktion von Alpträumen darstellen.
Outcomes Are in the Eye of the Beholder
Authors: Bee Colleen , Madrigal Robert
Published: January 2013

The purpose of the current research is to examine the influence of affective dispositions and the sequencing of affective and cognitive responses to mediated entertainment. Affective dispositions are manipulated to match a liked competitor against one who is disliked. The results indicate that viewers’ emotional responses and assessments of satisfaction with a win or loss were dependent on competitor liking. A hedonic reversal occurs in viewer disconfirmation emotions (relief and disappointment) and satisfaction judgments based on outcome desirability. A desirable (undesirable) outcome was one in which a liked (disliked) competitor won, or a disliked (liked) competitor lost. We also found evidence of mediated moderation such that competitor liking moderated the mediating effect of relief and disappointment on outcome satisfaction following an outcome. Outcome satisfaction, conceptualized as a cognitive judgment in our model, was then positively related to viewer enjoyment of the overall experience. Additionally our hypothesized model was found to outperform two competing models. The results elucidate the complex intertwining of affect and cognition in predicting viewer enjoyment of mediated entertainment.
Covering Your Face on Facebook
Authors: Strano Michele M. , Wattai Queen Jill
Published: January 2013

This study examines the ways in which identity is managed on social networking sites through image suppression practices – namely, untagging and requesting deletion on Facebook. Goffman’s theory of impression management is used, focusing on his understudied ideas about how individuals respond to what others communicate about them, by controlling for information that is discrepant with their desired self-presentation. Data are reported from an exploratory set of qualitative interviews and an online quantitative survey. Results showed that many Facebook users engaged in suppression strategies, albeit infrequently. In addition, users were statistically more likely to not post a potentially damaging image than they were to untag it, and were more likely to untag it than to request that another user delete it. The authors suggest that one possibility is that users avoid more overt identity management strategies because they carry the risk of making users look duplicitous. A potential model is suggested that future research might test to develop a fuller understanding of online identity management.
P2Y1R-Initiated, IP3R-Dependent Stimulation of Astrocyte Mitochondrial Metabolism Reduces and Partially Reverses Ischemic Neuronal Damage in Mouse
Authors: Zheng Wei , Watts Lora Talley , Holstein Deborah M , Wewer Jimmy , Lechleiter James D
Published: January 2013

Glia-based neuroprotection strategies are emerging as promising new avenues to treat brain damage. We previously reported that activation of the glial-specific purinergic receptor, P2Y1R, reduces both astrocyte swelling and brain infarcts in a photothrombotic mouse model of stroke. These restorative effects were dependent on astrocyte mitochondrial metabolism. Here, we extend these findings and report that P2Y1R stimulation with the purinergic ligand 2-methylthioladenosine 5′ diphosphate (2MeSADP) reduces and partially reverses neuronal damage induced by photothrombosis. In vivo neuronal morphology was confocally imaged in transgenic mice expressing yellow fluorescent protein under the control of the Thy1 promoter. Astrocyte mitochondrial membrane potentials, monitored with the potential sensitive dye tetra-methyl rhodamine methyl ester, were depolarized after photothrombosis and subsequently repolarized when P2Y1Rs were stimulated. Mice deficient in the astrocyte-specific type 2 inositol 1,4,5 trisphosphate (IP3) receptor exhibited aggravated ischemic dendritic damage after photothrombosis. Treatment of these mice with 2MeSADP did not invoke an intracellular Ca2+ response, did not repolarize astrocyte mitochondria, and did not reduce or partially reverse neuronal lesions induced by photothrombotic stroke. These results demonstrate that IP3-Ca2+ signaling in astrocytes is not only critical for P2Y1R-enhanced protection, but suggest that IP3-Ca2+ signaling is also a key component of endogenous neuroprotection.
EPR approaches to disorder in proteins
Authors: Huber Martina
Published: January 2013

Nature can be messy. Disorder often accompanies natural processes and in some cases may even be required for function. For biochemical and biophysical techniques, disordered systems are challenging, to the degree that traditional methods of structure determination either cannot be applied at all, or are severely limited. The methods suffer from broadening effects due to heterogeneity and multi-component spectra are often impossible to interpret.

The growing understanding that disorder and heterogeneity are important in biological processes and the increasing evidence that disordered regions in proteins may be functional,1 make it timely to take a current-day look at these subjects. The discovery in 19982 of intrinsically disordered proteins, or of proteins that function on account of disordered regions,3 is reflected in a textbook.4 Fig. 1 shows in a cartoon-fashion the interactions and different conformations that flexible proteins can adopt.
GINA—A polarized neutron reflectometer at the Budapest Neutron Centre
Authors: Bottyán L. , Merkel D. G. , Nagy B. , Füzi J. , Sajti Sz. , Deák L. , Endrőczi G. , Petrenko A. V. , Major J.
Published: January 2013

The setup, capabilities, and operation parameters of the neutron reflectometer GINA, the recently installed “Grazing Incidence Neutron Apparatus” at the Budapest Neutron Centre, are introduced. GINA, a dance-floor-type, constant-energy, angle-dispersive reflectometer is equipped with a 2D position-sensitive detector to study specular and off-specular scattering. Wavelength options between 3.2 and 5.7 Å are available for unpolarized and polarized neutrons. Spin polarization and analysis are achieved by magnetized transmission supermirrors and radio-frequency adiabatic spin flippers. As a result of vertical focusing by a five-element pyrolytic graphite monochromator, the reflected intensity from a 20 × 20 mm2 sample has been doubled. GINA is dedicated to studies of magnetic films and heterostructures, but unpolarized options for non-magnetic films, membranes, and other surfaces are also provided. Shortly after its startup, reflectivity values as low as 3 × 10−5 have been measured by the instrument. The instrument capabilities are demonstrated by a non-polarized and a polarized reflectivity experiment on a Si wafer and on a magnetic film of [62Ni/natNi]5 isotope-periodic layer composition. The facility is now open for the international user community. Its further development is underway establishing new sample environment options and spin analysis of off-specularly scattered radiation as well as further decreasing the background.
Nonlinear theory of drift-cyclotron kinetics and the possible breakdown of gyro-kinetics
Authors: Waltz R. E. , Deng Zhao
Published: January 2013

A nonlinear theory of drift-cyclotron kinetics (termed cyclo-kinetics here) is formulated to test the breakdown of the gyro-kinetic approximations. Six dimensional cyclo-kinetics can be regarded as an extension of five dimensional gyro-kinetics to include high-frequency cyclotron waves, which can interrupt the low-frequency gyro-averaging in the (sixth velocity grid) gyro-phase angle. Nonlinear cyclo-kinetics has no limit on the amplitude of the perturbations. Formally, there is no gyro-averaging when all cyclotron (gyro-phase angle) harmonics of the perturbed distribution function (delta-f) are retained. Retaining only the (low frequency) zeroth cyclotron harmonic in cyclo-kinetics recovers both linear and nonlinear gyro-kinetics. Simple recipes are given for converting continuum nonlinear delta-f gyro-kinetic transport simulation codes to cyclo-kinetics codes by retaining (at least some) higher cyclotron harmonics.
Gyrokinetic simulation of global and local Alfvén eigenmodes driven by energetic particles in a DIII-D discharge
Authors: Bass E. M. , Waltz R. E.
Published: January 2013

The unstable spectrum of Alfvén eigenmodes (AEs) driven by neutral beam-sourced energetic particles (EPs) in a benchmark DIII-D discharge (142111) is calculated in a fully gyrokinetic model using the GYRO code's massively parallel linear eigenvalue solver. One cycle of the slow (equilibrium scale) frequency sweep of the reverse shear Alfvén eigenmode (RSAE) at toroidal mode number n=3 is mapped. The RSAE second harmonic and an unstable beta-induced Alfvén eigenmode (BAE) are simultaneously tracked alongside the primary RSAE. An observed twist in the eigenmode pattern, caused mostly by shear in the driving EP profile, is shown through artificially varying the E×B rotational velocity shear to depend generally on shear in the local wave phase velocity. Coupling to the BAE and to the toroidal Alfvén eigenmode limit the RSAE frequency sweeps at the lower and upper end, respectively. While the present fully gyrokinetic model (including thermal ions and electrons) constitutes the best treatment of compressibility physics available, the BAE frequency is overpredicted by about 20% against experiment here and is found to be sensitive to energetic beam ion pressure. The RSAE frequency is more accurately matched except when it is limited by the BAE. Simulations suggest that the experiment is very close to marginal AE stability at points of RSAE-BAE coupling. A recipe for comparing the radial profile of quasilinear transport flux from local modes to that from global modes paves the way for the development of a stiff (critical gradient) local AE transport model based on local mode stability thresholds.
A simple but accurate potential for the naphthalene-argon complex: Applications to collisional energy transfer and matrix isolated IR spectroscopy
Authors: Calvo F. , Falvo Cyril , Parneix Pascal
Published: January 2013

An explicit polarizable potential for the naphthalene-argon complex has been derived assuming only atomic contributions, aiming at large scale simulations of naphthalene under argon environment. The potential was parametrized from dedicated quantum chemical calculations at the CCSD(T) level, and satisfactorily reproduces available structural and energetic properties. Combining this potential with a tight-binding model for naphthalene, collisional energy transfer is studied by means of dedicated molecular dynamics simulations, nuclear quantum effects being accounted for in the path-integral framework. Except at low target temperature, nuclear quantum effects do not alter the average energies transferred by the collision or the collision duration. However, the distribution of energy transferred is much broader in the quantum case due to the significant zero-point energy and the higher density of states. Using an ab initio potential for the Ar-Ar interaction, the IR absorption spectrum of naphthalene solvated by argon clusters or an entire Ar matrix is computed via classical and centroid molecular dynamics. The classical spectra exhibit variations with growing argon environment that are absent from quantum spectra. This is interpreted by the greater fluxional character experienced by the argon atoms due to vibrational delocalization.
Optimization of operation of a three-electrode gyrotron with the use of a flow-type calorimeter
Authors: Kharchev Nikolay K. , Batanov German M. , Kolik Leonid V. , Malakhov Dmitrii V. , Petrov Aleksandr Ye. , Sarksyan Karen A. , Skvortsova Nina N. , Stepakhin Vladimir D. , Belousov Vladimir I. , Malygin Sergei A. , Tai Yevgenii M.
Published: January 2013

Results are presented for measurements of microwave power of the Borets-75/0.8 gyrotron with recovery of residual electron energy, which were performed by a flow-type calorimeter. This gyrotron is a part of the ECR plasma heating complex put into operation in 2010 at the L-2M stellarator. The new calorimeter is capable of measuring microwave power up to 0.5 MW. Monitoring of the microwave power makes it possible to control the parameters of the gyrotron power supply unit (its voltage and current) and the magnetic field of the cryomagnet in order to optimize the gyrotron operation and arrive at maximum efficiency.
Computational chemical analysis of unconjugated bilirubin anions and insights into pKa values clarification
Authors: Vega-Hissi Esteban G. , Estrada Mario R. , Lavecchia Martín J. , Pis Diez Reinaldo
Published: January 2013

The pKa, the negative logarithm of the acid dissociation equilibrium constant, of the carboxylic acid groups of unconjugated bilirubin in water is a discussed issue because there are quite different experimental values reported. Using quantum mechanical calculations we have studied the conformational behavior of unconjugated bilirubin species (in gas phase and in solution modeled implicitly and explicitly) to provide evidence that may clarify pKa values because of its pathophysiological relevance. Our results show that rotation of carboxylate group, which is not restricted, settles it in a suitable place to establish stronger interactions that stabilizes the monoanion and the dianion to be properly solvated, demonstrating that the rationalization used to justify the high pKa values of unconjugated bilirubin is inappropriate. Furthermore, low unconjugated bilirubin (UCB) pKa values were estimated from a linear regression analysis.
Multiple population-period transient spectroscopy (MUPPETS) in excitonic systems
Authors: Wu Haorui , Berg Mark A.
Published: January 2013

Time-resolved experiments with more than one period of incoherent time evolution are becoming increasingly accessible. When applied to a two-level system, these experiments separate homogeneous and heterogeneous contributions to kinetic dispersion, i.e., to nonexponential relaxation. Here, the theory of two-dimensional (2D) multiple population-period transient spectroscopy (MUPPETS) is extended to multilevel, excitonic systems. A nonorthogonal basis set is introduced to simplify pathway calculations in multilevel systems. Because the exciton and biexciton signals have different signs, 2D MUPPETS cleanly separates the exciton and biexciton decays. In addition to separating homogeneous and heterogeneous dispersion of the exciton, correlations between the exciton and biexciton decays are measurable. Such correlations indicate shared features in the two relaxation mechanisms. Examples are calculated as both 2D time decays and as 2D rate spectra. The effect of solvent heating (i.e., thermal gratings) is also calculated in multidimensional experiments on multilevel systems.
Velocity effects on the shape of pure H2O isolated lines: Complementary tests of the partially correlated speed-dependent Keilson-Storer model
Authors: Tran H. , Ngo N. H. , Hartmann J.-M. , Gamache R. R. , Mondelain D. , Kassi S. , Campargue A. , Gianfrani L. , Castrillo A. , Fasci E. , Rohart F.
Published: January 2013

Complementary tests of the partially correlated speed-dependent Keilson-Storer (pCSDKS) model for the shape of isolated transition of pure water vapor [N. H. Ngo et al., J. Chem. Phys. 136, 154310 (2012)]10.1063/1.4704675 are made using new measurements. The latter have been recorded using a high sensitivity cavity ring down spectrometer, for seven self-broadened H2O lines in the 1.6 μm region at room temperature and for pressures from 0.5 to 15 Torr. Furthermore, the H218O spectra of [M. D. De Vizia et al., Phys. Rev. A 83, 052506 (2011)]10.1103/PhysRevA.83.052506 in the 1.38 μm region, measured at 273.15 K and for pressures from 0.3 to 3.75 Torr have also been used for comparison with the model. Recall that the pCSDKS model takes into account the collision-induced velocity changes, the speed dependences of the broadening and shifting coefficients as well as the partial correlation between velocity and rotational-state changes. All parameters of the model have been fixed at values previously determined, except for a scaling factor applied to the input speed-dependent line broadening. Comparisons between predictions and experiments have been made by looking at the results obtained when fitting the calculated and measured spectra by Voigt profiles. The good agreement obtained for all considered lines, at different temperature and pressure conditions, confirms the consistency and the robustness of the model. Limiting cases of the model have been then derived, showing the influence of different contributions to the line shape.
Impact system for ultrafast synchrotron experiments
Authors: Jensen B. J. , Owens C. T. , Ramos K. J. , Yeager J. D. , Saavedra R. A. , Iverson A. J. , Luo S. N. , Fezzaa K. , Hooks D. E.
Published: January 2013

The impact system for ultrafast synchrotron experiments, or IMPULSE, is a 12.6-mm bore light-gas gun (<1 km/s projectile velocity) designed specifically for performing dynamic compression experiments using the advanced imaging and X-ray diffraction methods available at synchrotron sources. The gun system, capable of reaching projectile velocities up to 1 km/s, was designed to be portable for quick insertion/removal in the experimental hutch at Sector 32 ID-B of the Advanced Photon Source (Argonne, IL) while allowing the target chamber to rotate for sample alignment with the beam. A key challenge in using the gun system to acquire dynamic data on the nanosecond time scale was synchronization (or bracketing) of the impact event with the incident X-ray pulses (80 ps width). A description of the basic gun system used in previous work is provided along with details of an improved launch initiation system designed to significantly reduce the total system time from launch initiation to impact. Experiments were performed to directly measure the gun system time and to determine the gun performance curve for projectile velocities ranging from 0.3 to 0.9 km/s. All results show an average system time of 21.6 ± 4.5 ms, making it possible to better synchronize the gun system and detectors to the X-ray beam.
Normally off AlGaN/GaN high electron mobility transistors with p-InGaN cap layer
Authors: Mizutani Takashi , Yamada Hiroyuki , Kishimoto Shigeru , Nakamura Fumihiko
Published: January 2013

Normally off AlGaN/GaN HEMTs with a p-In0.23Ga0.77N cap layer were successfully fabricated. The key idea in this approach is to employ the polarization-induced field in the InGaN cap and negative charge in the p-InGaN cap; this raises the conduction band at the AlGaN/GaN interface and leads to normally off operation. A threshold voltage of 1.2 V and maximum transconductance of 146 mS/mm were obtained. The gate leakage current of the InGaN-capped AlGaN/GaN HEMTs was investigated in detail. The V-shaped defects originating from the AlGaN surface have been shown to be responsible for the gate leakage current. The insertion of a thin GaN layer between the p-InGaN and AlGaN layers was shown to be effective in suppressing the formation of V-shaped defects and decreasing the gate leakage current.
Field-effect-based chemical sensing using nanowire-nanoparticle hybrids: The ion-sensitive metal-semiconductor field-effect transistor
Authors: Pachauri Vivek , Kern Klaus , Balasubramanian Kannan
Published: January 2013

A new class of nanoscale devices called ion-sensitive metal-semiconductor field-effect transistors (nano-IS-MESFET) for sensing applications is reported. Nanoparticle-nanowire hybrids with active metal-semiconductor regions are operated as ion-sensitive field-effect transistors (ISFETs) in liquids, where 0D metal gates induce quasi-spherical charge depletion regions in 1D transport channel producing stronger field-effects. As a proof-of-concept, we present ZnO nanowire-Pd/Au nanoparticle IS-MESFETs that show increased transconductance in comparison to ZnO nanowire ISFETs. As demonstrated further, ISMESFETs may also provide strategies for site-specific immobilization of receptor molecules paving way towards a novel electrical biosensing platform operable at low voltages with improved selectivity and sensitivity.
On the confinement of semiflexible chains under torsion
Authors: Emanuel Marc
Published: January 2013

The effect of a finite torque on semiflexible polymers in a confined environment is investigated. It is shown how a new length scale appears in the strongly confined limit. The influence of a torque on the extension of biopolymers in nanochannels is also touched upon and it is argued that the presence of a torque has a strong influence on the dimensions of nanochannels needed to prevent hairpins.
Interpretation of changes in diffusive and non-diffusive transport in the edge plasma during pedestal buildup following a low-high transition in DIII-D
Authors: Stacey W. M. , Sayer M.-H. , Floyd J.-P. , Groebner R. J.
Published: January 2013

The evolution of diffusive and non-diffusive transport during pedestal buildup following a low-high (L-H) transition has been interpreted from a particle-momentum-energy balance analysis of the measured density, temperature, and rotation velocity profiles in the plasma edge (0.82<ρ<1.0) of a DIII-D [Luxon, Nucl. Fusion 42, 614 (2002)] discharge. In the discharge examined, there was an edge-localized-mode-free period of more than 600 ms following the L-H transition, and the majority of edge pedestal development occurred within the first 100 ms following the L-H transition. There appears to be a spatio-temporal correlation among the measured toroidal and poloidal rotation, the formation of a negative well in the measured radial electric field, the creation of a large inward particle pinch, the calculated intrinsic rotation due to ion orbit loss, and the measured formation of steep gradients in density and temperature in the outer region (ρ>0.95) of the edge pedestal.