bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing Emergent Surgical Cricothyrotomy for use in Austere Environments
Authors: Hessert M. Josephine , Bennett Brad L.
Published: October 2012

Emergent cricothyrotomy is an infrequently performed procedure used in the direst of circumstances on the most severely injured patients. Austere environments present further unique challenges to effective emergency medical practice. Recently, military trauma registry data were searched for the frequency of cricothyrotomy use and success rates during a 22-month period. These data revealed that cricothyrotomy performed in the most rigorous austere environment (ie, battlefield) had many successes, but also a large number of failed (33%) attempts by medics owing to many factors. Thus, the aim of this review article is to present what is known about cricothyrotomy and apply this knowledge to any austere environment for qualified providers. The National Library of Medicine's PubMed was used to conduct a thorough search using the terms “prehospital,” “cricothyroidotomy,” “cricothyrotomy,” and “surgical airway.” The findings were further narrowed by applicability to the austere environment. This review presents relevant airway anatomy, incidences, indications, contraindications, procedures, and equipment, including improvised devices, success rates, complications, and training methods. Recommendations are proffered for ways to optimize procedures, equipment, and training for successful application of this emergent skill set in the austere environment.
JURISDICTION FOR CROSS-BORDER BREACH OF PERSONALITY AND DEFAMATION: EDATE ADVERTISING AND MARTINEZ
Authors: Gillies Lorna
Published: October 2012

In the conjoined cases C-509/09 e-Date Advertising GmbH v X and C-161/10 Olivier Martinez and others v MGN Ltd,1 the Court of Justice of the European Union (CJEU) was required to determine the scope of applicability of both Article 5(3) of Regulation EC 44/2001 (the Brussels I Regulation)2 and Article 3 of Directive EC 2000/31 (the Electronic Commerce Directive). Both cases were concerned with defamation and breach of personality and image rights as a result of the publication of two newspaper articles which were accessible online via each of the defendants' websites. As readers will be fully aware, Article 5(3) of the Brussels I Regulation enables claimants to establish special jurisdiction in the case of a tort, delict or quasi-delict, in the courts of the Member State where a harmful event has occurred or may occur. The effectiveness of Article 5(3) as a ground of jurisdiction focuses on the locality of the event. The question that arose in both cases was, essentially, where could the claimants bring proceedings for breach of personality and defamation as a result of newspaper articles published online via websites,3 when those websites were accessible in multiple jurisdictions? According to an experienced legal practitioner in the United Kingdom, ‘more than 25 billion individual items of content are shared each month on Facebook alone.’4 There are increasing concerns regarding the dissemination of comments through the medium of ‘ubiquit(ous), converged and displace(d)’5 Web 2.0 communications technologies. Such communications increase the potential for criminal and civil consequences in numerous jurisdictions. The ability of injured parties (famous or not) to seek redress in the most appropriate forum for the purposes of protecting their private lives and reputations is acutely significant.6
An environmental assessment of the parasite fauna of the reef-associated grouperEpinephelus areolatusfrom Indonesian waters
Authors: Kleinertz S. , Damriyasa I.M. , Hagen W. , Theisen S. , Palm H.W.
Published: October 2012

SixtyEpinephelus areolatuswere examined for metazoan fish parasites in Indonesia, off Segara Anakan lagoon, Java and in Balinese waters. The study revealed 21 different parasite species, and 14 new host and locality records. The anisakid nematodesAnisakis typicaand, for the first time in Indonesia,Anisakissp. HC-2005 were identified by using molecular methods. Ecological parameters were calculated for both sites off the anthropogenically influenced Segara Anakan lagoon and the relatively undisturbed reference site at the southern Balinese coast. The fish from Segara Anakan demonstrated a significantly higher enzymatic activity (Hepatosomatic index) and a significantly reduced number of heteroxenous gut helminths (e.g. the digeneanDidymodiclinussp., the nematodeRaphidascarissp. and the acanthocephalanSerrasentis sagittifer). Other regional differences forE. areolatusincluded ecto-/endoparasite ratio, endoparasite diversity, the parasite species composition and prevalence of infection of the respective parasite species. We applied the stargraph method to visualize observed regional differences using grouper parasites as biological indicators for the sampled coastal ecosystems at both sampling sites.
High-risk occupations for suicide
Authors: Roberts S. E. , Jaremin B. , Lloyd K.
Published: October 2012

Background

High occupational suicide rates are often linked to easy occupational access to a method of suicide. This study aimed to compare suicide rates across all occupations in Britain, how they have changed over the past 30 years, and how they may vary by occupational socio-economic group.

Method

We used national occupational mortality statistics, census-based occupational populations and death inquiry files (for the years 1979–1980, 1982–1983 and 2001–2005). The main outcome measures were suicide rates per 100 000 population, percentage changes over time in suicide rates, standardized mortality ratios (SMRs) and proportional mortality ratios (PMRs).

Results

Several occupations with the highest suicide rates (per 100 000 population) during 1979–1980 and 1982–1983, including veterinarians (ranked first), pharmacists (fourth), dentists (sixth), doctors (tenth) and farmers (thirteenth), have easy occupational access to a method of suicide (pharmaceuticals or guns). By 2001–2005, there had been large significant reductions in suicide rates for each of these occupations, so that none ranked in the top 30 occupations. Occupations with significant increases over time in suicide rates were all manual occupations whereas occupations with suicide rates that decreased were mainly professional or non-manual. Variation in suicide rates that was explained by socio-economic group almost doubled over time from 11.4% in 1979–1980 and 1982–1983 to 20.7% in 2001–2005.

Conclusions

Socio-economic forces now seem to be a major determinant of high occupational suicide rates in Britain. As the increases in suicide rates among manual occupations occurred during a period of economic prosperity, carefully targeted suicide prevention initiatives could be beneficial.
Patients with bipolar disorders share similar but attenuated prospective memory impairments with patients with schizophrenia
Authors: Chan R. C. K. , Lui S. S. Y. , Wang Y. , Liu A. C. Y. , Chui W. W. H. , Shum D. H. K. , Cheung E. F. C.
Published: October 2012

Background

Prospective memory (PM) refers to the ability to remember to carry out an intended action in the future. PM is consistently found to be impaired in individuals with schizophrenia. Bipolar disorder and schizophrenia may represent conditions along a continuum, and share similar neurocognitive and genetic architecture. This study aimed to compare the nature and extent of PM impairment in individuals with schizophrenia and bipolar disorder.

Method

Participants were 38 out-patients with schizophrenia and 40 out-patients with bipolar disorder in an early psychosis intervention programme, and 37 healthy controls. Time-, event- and activity-based PMs were assessed using a dual-task laboratory paradigm. Self-reported PM performance was gauged using the Prospective and Retrospective Memory Questionnaire. Analysis of covariance (ANCOVA), with intelligence quotient (IQ) and education included as covariates, was used to examine group difference on various types of PM. Repeated measures of ANCOVA were used to examine the group × PM type interaction effect. Correspondence between laboratory and self-reported PM measures was examined using correlational analysis.

Results

The group × PM type interaction effect was not significant, but the main effect of group was significant. Patients with schizophrenia and patients with bipolar disorder both performed more poorly than healthy participants in PM. The two clinical groups did not significantly differ in PM. Laboratory and self-reported PM measures did not correlate significantly with each other.

Conclusions

Patients with bipolar disorder shared a similar PM impairment with those with schizophrenia. Findings of this study extended the similarity in neurocognitive impairments between the two psychiatric disorders to PM.
Endophytic bacterial diversity of an Antarctic moss, Sanionia uncinata
Authors: Park Mira , Lee Hyoungseok , Hong Soon Gyu , Kim Ok-Sun
Published: October 2012

Although the beneficial effects of endophytic bacteria on their host are significant, the investigation of the microbial diversity in any Antarctic moss has been neglected. In this study, we investigate the endophytic bacterial diversity of the upper green part and the lower brown part of Sanionia uncinata through 16S rRNA genes using pyrosequencing. Proteobacteria was the most dominant phylum with 65.6%, followed by Bacteroidetes (29.1%) and Actinobacteria (11.7%). The different distribution of Alphaproteobacteria between the upper green (2%) and lower brown (22.2%) parts of the moss was significant. Furthermore, dominant and diverse species were detected and closely related to the environmental sequences. These findings suggest that there are likely to be specific relationships between endophytes and host Antarctic moss species.
Nutrient intakes of children aged 1–2 years as a function of milk consumption, cows’ milk or growing-up milk
Authors: Ghisolfi Jacques , Fantino Marc , Turck Dominique , de Courcy Geneviève Potier , Vidailhet Michel
Published: October 2012

Objective

To evaluate the nutritional adequacy of diets in early childhood as a function of milk intake, cows’ milk (CM) or growing-up milk (GUM).

Design

From a cross-sectional food consumption survey, two groups of children aged 1–2 years were defined: Group CM fed exclusively on CM ≥ 250 ml/d and Group GUM fed on GUM ≥ 250 ml/d. Proportions of children at risk of nutrient excess or insufficiency were estimated relative to the French Recommended Daily Allowances, Estimated Average Requirements or Adequate Intakes.

Setting

Parents participating in the survey were recruited from all regions of France by a polling organization. Distribution was adjusted to that of the French population.

Subjects

Sixty-three (Group CM) and fifty-five (Group GUM) children.

Results

Total energy and macronutrient intakes were similar in the two groups except protein intake of Group CM, which was much higher than the Recommended Daily Allowance and significantly higher than in Group GUM. A high percentage of children of Group CM had intake of linoleic acid (51 %) and α-linolenic acid (84 %) below the lower limit of the Adequate Intake, and intake of Fe (59 %) vitamin C (49 %) and alimentary vitamin D (100 %) less than the Estimated Average Requirement. Significant differences were observed in the proportions of children with a risk of dietary inadequacy between the two groups for all the mentioned nutrients (P < 0·001). In Group GUM, this imbalance was only observed for vitamin D. Intake of foods other than milk and dairy products could not account for these discrepancies.

Conclusions

Consumption of CM (≥250 ml/d) entails the risk of insufficiency in α-linolenic acid, Fe, vitamin C and vitamin D. Use of GUM (≥250 ml/d) significantly reduces the risk of insufficiencies in the mentioned nutrients.
Microstructural Characterization of Consolidant Products for Historical Renders: An Innovative Nanostructured Lime Dispersion and a More Traditional Ethyl Silicate Limewater Solution
Authors: Borsoi Giovanni , Tavares Martha , Veiga Rosário , Silva Antonio Santos
Published: October 2012

The conservation and durability of historical renders must be carried out through compatible techniques and materials. An important operation is the restitution of historical renders cohesion, turned friable by the loss of binder, usually due to physical and/or chemical actions. Surface consolidation is based on the use of materials with aggregating properties. This operation is reached usually through the application of organic or mineral consolidants, but inorganic consolidants are becoming preferred due to better compatibility and durability. In this article two mineral compatible consolidation products were studied: a commercial suspension of calcium hydroxide nanoparticles in propanol and a limewater dispersion of ethyl silicate. Microscopy (optical and scanning electron microscopy) and X-ray microanalyses of the consolidation products and of the consolidated mortar specimens were carried out. To assess the mechanical properties and product's efficacy, analyses of the compression, flexural strength, and superficial hardness were performed. Microscopy results show that limewater dispersion of ethyl silicate forms platelike silica gels, which can interfere in product penetration. Otherwise, nanolime particles permit homogeneous distribution and optimum penetration on the treated substrate, improving cementing action and the agglomeration process.
What Remains to Be Done to Allow Quantitative X-Ray Microanalysis Performed with EDS to Become a True Characterization Technique?
Authors: Gauvin Raynald
Published: October 2012

This article reviews different methods used to perform quantitative X-ray microanalysis in the electron microscope and also demonstrates the urgency of measuring the fundamental parameters of X-ray generation for the development of accurate standardless quantitative methods. Using ratios of characteristic lines acquired on the same X-ray spectrum, it is shown that the Cliff and LorimerKA-Bfactor can be used in a general correction method that is appropriate for all types of specimens and electron microscopes, providing that appropriate corrections are made for X-ray absorption, fluorescence, and indirect generation. Since the fundamental parameters appear in theKA-Bfactor, only the ratio of the ionization cross sections needs to be known, not their absolute values. In this regard, the measurement of ratios of theKA-Bfactor (or intensities at different beam energies of the same material with no change of beam spreading in the material) permits the validation for the best models to compute the ratio of ionization cross sections. It is shown, using this method, that the nonrelativistic Bethe equation, to compute ionization cross section, is very close to the equation of E. Casnati et al. (J Phys B15, 155–167, 1982) and also to the equations proposed by D. Bote and F. Salvat (Phys Rev A77, 042701, 2008) for the computation of the ratio of ionization cross sections. The method is extended to show that it could be used to determine the values of the Coster-Kronig transitions factors, an important fundamental parameter for the generation of L and M lines that is mostly known with poor accuracy. The detector efficiency can be measured with specimens where their intensities were measured with an energy dispersive spectrometer detector, the efficiency of which has been measured in an X-ray synchrotron (M. Alvisi et al.,Microsc Microanal12, 406–415, 2006). The spatial resolution should always be computed when performing quantitative X-ray microanalysis and the equations of R. Gauvin (Microsc Microanal13(5), 354–357, 2007) for bulk materials and the one presented in this article for thin films should be used. The effects of X-rays generated by fast secondary electrons and by Auger electrons are reviewed, and their effect can be detrimental for the spatial resolution of materials involving low-energy X-ray lines, in certain specific conditions. Finally, quantitative X-ray microanalysis of heterogeneous materials is briefly reviewed.
HealthTwiSt: The Berlin Twin Registry for Health Research
Authors: Busjahn Andreas
Published: October 2012

The Berlin Twin Registry has its focus on health research. It is operated as a private company, making twin studies available to academic institutions as well as commercial partners in the area of biotechnology and nutrition. Recruitment is based on invitation in the context of mass media coverage of scientific results. Phenotyping in the unselected twin subjects is directed toward intermediate phenotypes that can bear on common diseases. These phenotypes include proteomic approaches and gene expression. Some results are briefly described to give an impression of the range of research topics and related opportunities for retrospective and prospective collaborative research.
D region meteoric smoke and neutral temperature retrieval using the poker flat incoherent scatter radar
Authors: Fentzke J. T. , Hsu V. , Brum C. G. M. , Strelnikova I. , Rapp M. , Nicolls M.
Published: October 2012

This brief note describes the first measurement of the microphysical properties and variability of meteoric smoke particles (MSPs) at high latitude using the Poker Flat ISR (65.1°N, 147.5°W). We present a novel technique for determining height resolved daytime D region neutral temperatures, which takes into account the presence of charged dust. We discuss the temporal/spatial variability and the relation to meteoric input observed and MSP microphysical properties in the polar mesopause region. The derived nanometer sized MSPs are consistent with size profiles derived previously using radar/rocket techniques and we note that our results imply a lack of heavy cluster ions below 85 km during the observing period. This provides a template for potential use at many other radar sites for the determination of microphysical properties of MSPs and day‐time neutral temperature in the D region that show good general agreement with model and satellite temperature data during the observing period.
Reexamining the warming in the tropical upper troposphere: Models versus radiosonde observations
Authors: Seidel Dian J. , Free Melissa , Wang James S.
Published: October 2012

A recent study of 1979–2010 tropical tropospheric temperature trends in climate model simulations and satellite microwave sounding unit (MSU) observations concluded that, although both showed greater warming in the upper than lower troposphere, the vertical amplification of warming was exaggerated in most models. We repeat that analysis of temperature trends, vertical difference trends, and trend ratios using five radiosonde datasets. Some, but not all, comparisons support the notion that vertical amplification in models exceeds that observed. However, larger ranges of radiosonde trends compared with those for MSU, and the sensitivity of results to the upper‐tropospheric level analyzed, make it difficult to conclude unambiguously that models are inconsistent with radiosonde observations. The larger ranges are due to the availability of more radiosonde datasets with different approaches for adjusting measurement biases. Together these two studies highlight challenges of using imperfect observations of tropical tropospheric temperature over a few decades to assess climate model performance.
Permeability‐porosity relationships of shallow mudstones in the Ursa Basin, northern deepwater Gulf of Mexico
Authors: Reece Julia Schneider , Flemings Peter B. , Dugan Brandon , Long Hui , Germaine John T.
Published: October 2012

In the Ursa Basin, Gulf of Mexico, in situ mudstone permeability near the seafloor declines from 1.1 × 10−16 to 5.8 × 10−19 m2over a depth of 578 m. We can reproduce this in situ permeability‐porosity behavior through consolidation experiments in the laboratory. We use uniaxial constant‐rate‐of‐strain consolidation experiments to measure permeability‐porosity relationships and derive in situ permeabilities of 31 mudstone samples collected at Integrated Ocean Drilling Program (IODP) Sites U1324 and U1322. Although these mudstones have similar grain‐size distributions, permeability at a given porosity varies significantly between the samples due to small variations in composition or fabric. We calculate an upscaled permeability relationship based on the observed permeability variation in the samples and determine a resultant large‐scale permeability anisotropy of around 30. Based on this upscaled relationship and observations of in situ pressure, we calculate upward fluid flow rates of 0.5 mm/yr. We find that given the observed compressibility, permeability, and the geologic forcing at Ursa, overpressures are predicted as observed in the subsurface. The primary mechanism for overpressure generation at Ursa is sediment loading due to rapid burial. Low vertical permeabilities, accompanied by high sedimentation rates, can cause severe overpressure near the seafloor, which controls fluid flow and can reduce slope stability as observed in the Mississippi Canyon region. Such flow systems, especially at intermediate depths on passive margins, are important due to their control over macroscale behavior such as topographic gradient of continental slopes and submarine landslides, but have been largely understudied in the past.
Synthetic radiance simulation and evaluation for a Joint Observing System Simulation Experiment
Authors: Zhu Tong , Weng Fuzhong , Masutani Michiko , Woollen Jack S.
Published: October 2012

Since 2006, a Joint Observing System Simulation Experiment (OSSE) project has been established at the United States Joint Center for Satellite Data Assimilation. The work provided here documents the simulation of synthetic satellite observations from the OSSE Nature Run (NR) and the evaluation of the simulated results. The Community Radiative Transfer Model was used to produce synthetic satellite observations, which will be assimilated in the Gridpoint Statistical Interpolation system. Synthetic radiances were evaluated through a comparison with real observations and model simulations obtained from National Center for Environmental Prediction (NCEP) Global Forecast System (GFS) 6 h forecast fields. For both IR and microwave sensors, we determined that the bias and the standard deviation of the synthetic radiances were in good agreement with real observations. At the NR initial time, the simulated Advanced Microwave Sounding Unit‐A (AMSU‐A) radiances reproduced observed AMSU‐A interchannel correlations and symmetric angular‐dependent features. However, the asymmetric angular‐dependent bias, mainly related to AMSU‐A instrument polarization misalignment, cloud not be simulated properly. The simulated GOES‐12 Sounder radiances indicated that the error characteristics of atmospheric temperature sounding channels were similar to those from the NCEP operational GFS analysis system, and those biases of moisture and surface channels were approximately 2 K. To mimic real observational errors, random (Gaussian distribution) errors with the mean and variance estimated by the differences between observations and GFS fields were added to the synthetic radiances, resulting in a 20–30% increase in the standard deviations of the synthetic radiances.
Structure and function of the PorB porin from disseminating Neisseria gonorrhoeae
Authors: Zeth Kornelius , Kozjak-Pavlovic Vera , Faulstich Michaela , Fraunholz Martin , Hurwitz Robert , Kepp Oliver , Rudel Thomas
Published: October 2012

The outer membrane of Gram-negative bacteria contains a large number of channel-forming proteins, porins, for the uptake of small nutrient molecules. Neisseria gonorrhoeae PorBIA (PorB of serotype A) are associated with disseminating diseases and mediate a rapid bacterial invasion into host cells in a phosphate-sensitive manner. To gain insights into this structure–function relationship we analysed PorBIA by X-ray crystallography in the presence of phosphate and ATP. The structure of PorBIA in the complex solved at a resolution of 3.3 Å (1 Å=0.1 nm) displays a surplus of positive charges inside the channel. ATP ligand-binding in the channel is co-ordinated by the positively charged residues of the channel interior. These residues ligate the aromatic, sugar and pyrophosphate moieties of the ligand. Two phosphate ions were observed in the structure, one of which clamped by two arginine residues (Arg92 and Arg124) localized at the extraplasmic channel exit. A short β-bulge in β2-strand together with the long L3 loop narrow the barrel diameter significantly and further support substrate specificity through hydrogen bond interactions. Interestingly the structure also comprised a small peptide as a remnant of a periplasmic protein which physically links porin molecules to the peptidoglycan network. To test the importance of Arg92 on bacterial invasion the residue was mutated. In vivo assays of bacteria carrying a R92S mutation confirmed the importance of this residue for host-cell invasion. Furthermore systematic sequence and structure comparisons of PorBIA from Neisseriaceae indicated Arg92 to be unique in disseminating N. gonorrhoeae thereby possibly distinguishing invasion-promoting porins from other neisserial porins.
First principles calculation of dopant solution energy in HfO2 polymorphs
Authors: Saitoh M. , Mizoguchi T. , Tohei T. , Ikuhara Y.
Published: October 2012

The solution behavior of dopants, Si, La, and N, in HfO2 polymorphs, monoclinic, tetragonal, and cubic was investigated by using a first principles calculation based on density functional theory within the local density approximation. It was found that the Si and La solutions are more preferable under oxidization atmosphere than reduction atmosphere, and the most efficient nitridation condition for the HfO2 is NO/NO2 atmosphere. By comparing the energy difference between the monoclinic and the tetragonal phases, it was found that the energy difference is decreased by the Si or La doping, whereas influence of the N doping is small, indicating that the phase transition from the monoclinic to tetragonal phase would be enhanced by the Si or La doping.
Development of a method for measuring the density of liquid sulfur at high pressures using the falling-sphere technique
Authors: Funakoshi Ken-ichi , Nozawa Akifumi
Published: October 2012

We describe a new method for the in situ measurement of the density of a liquid at high pressure and high temperature using the falling-sphere technique. Combining synchrotron radiation X-ray radiography with a large-volume press, the newly developed falling-sphere method enables the determination of the density of a liquid at high pressure and high temperature based on Stokes’ flow law. We applied this method to liquid sulfur and successfully obtained the density at pressures up to 9 GPa. Our method could be used for the determination of the densities of other liquid materials at higher static pressures than are currently possible.
The compressibility of nanocrystalline Pt
Authors: Mikheykin A. S. , Dmitriev V. P. , Chagovets S. V. , Kuriganova A. B. , Smirnova N. V. , Leontyev I. N.
Published: October 2012

High-pressure behavior of carbon supported Pt nanoparticles (Pt/C) with an average particle size of 10.6 nm was investigated by in situ high-pressure synchrotron radiation x-ray diffraction up to 14 GPa at ambient temperature. Our results show that the compressibility of Pt/C nanoparticles decreases substantially as the particle size decreases. An interpretation based upon the available mechanisms of structural compliance in nanoscale vs bulk materials was proposed.
Coherent growth of superconducting TiN thin films by plasma enhanced molecular beam epitaxy
Authors: Krockenberger Yoshiharu , Karimoto Shin-ichi , Yamamoto Hideki , Semba Kouich
Published: October 2012

We have investigated the formation of titanium nitride (TiN) thin films on (001) MgO substrates by molecular beam epitaxy and radio frequency acitvated nitrogen plasma. Although cubic TiN is stabile over a wide temperature range, superconducting TiN films are exclusively obtained when the substrate temperature exceeds 710 °C. TiN films grown at 720 °C show a high residual resistivity ratio of approximately 11 and the superconducting transition temperature (Tc) is well above 5 K. Superconductivity has been confirmed also by magnetiztion measurements. In addition, we determined the upper critical magnetic field (μ0Hc2) as well as the corresponding coherence length (ξGL) by transport measurements under high magnetic fields. High-resolution transmission electron microscopy data revealed full in plane coherency to the substrate as well as a low defect density in the film, in agreement with a mean-free path length ℓ ≈ 106 nm, which is estimated from the residual resistivity value. The observations of reflection high energy electron diffraction intensity oscillations during the growth, distinct Laue fringes around the main Bragg peaks, and higher order diffraction spots in the reciprocal space map suggest the full controlability of the thickness of high quality superconducting TiN thin films.
Peptide kinetics from picoseconds to microseconds using boxed molecular dynamics: Power law rate coefficients in cyclisation reactions
Authors: Shalashilin Dmitrii V. , Beddard Godfrey S. , Paci Emanuele , Glowacki David R.
Published: October 2012

Molecular dynamics (MD) methods are increasingly widespread, but simulation of rare events in complex molecular systems remains a challenge. We recently introduced the boxed molecular dynamics (BXD) method, which accelerates rare events, and simultaneously provides both kinetic and thermodynamic information. We illustrate how the BXD method may be used to obtain high-resolution kinetic data from explicit MD simulations, spanning picoseconds to microseconds. The method is applied to investigate the loop formation dynamics and kinetics of cyclisation for a range of polypeptides, and recovers a power law dependence of the instantaneous rate coefficient over six orders of magnitude in time, in good agreement with experimental observations. Analysis of our BXD results shows that this power law behaviour arises when there is a broad and nearly uniform spectrum of reaction rate coefficients. For the systems investigated in this work, where the free energy surfaces have relatively small barriers, the kinetics is very sensitive to the initial conditions: strongly non-equilibrium conditions give rise to power law kinetics, while equilibrium initial conditions result in a rate coefficient with only a weak dependence on time. These results suggest that BXD may offer us a powerful and general algorithm for describing kinetics and thermodynamics in chemical and biochemical systems.
A novel technique for single-shot energy-resolved 2D x-ray imaging of plasmas relevant for the inertial confinement fusion
Authors: Labate L. , Köster P. , Levato T. , Gizzi L. A.
Published: October 2012

A novel x-ray diagnostic of laser-fusion plasmas is described, allowing 2D monochromatic images of hot, dense plasmas to be obtained in any x-ray photon energy range, over a large domain, on a single-shot basis. The device (named energy-encoded pinhole camera) is based upon the use of an array of many pinholes coupled to a large area CCD camera operating in the single-photon mode. The available x-ray spectral domain is only limited by the quantum efficiency of scientific-grade x-ray CCD cameras, thus extending from a few keV up to a few tens of keV. Spectral 2D images of the emitting plasma can be obtained at any x-ray photon energy provided that a sufficient number of photons had been collected at the desired energy. Results from recent inertial confinement fusion related experiments will be reported in order to detail the new diagnostic.
Analysis of a device model for organic pseudo-bilayer solar cells
Authors: Zhang Teng , Birgersson Erik , Ananthanarayanan Krishnamoorthy , Yong Chian Haw , Thummalakunta L. N. S. A. , Luther Joachim
Published: October 2012

Polymer solar cells fabricated through sequential-solution-processing of donor and acceptor materials consist of partially intermixed heterojunctions and are therefore termed as organic “pseudo-bilayer” solar cells. A steady-state model for such organic pseudo-bilayer solar cells, which generalizes the bulk-heterojunction and the bilayer solar cell models, is derived based on a donor-blend-acceptor structure for the active layer. In short, the model considers intrinsic solar cell physics such as optical generation, charge carrier transport, generation, and recombination, as well as the space charge effect. Parameter fitting and model validation are carried out with current-voltage measurements from in-house fabricated pseudo-bilayer solar cells. The model shows that even with a large exciton diffusion length, a pure large-molecule bilayer cell is unable to produce the photocurrents seen in the measurements. This confirms the experimental observation that an intermixed region, instead of a well-defined interface, exists between the donor and acceptor phases in pseudo-bilayer solar cells. In addition, the effect of blend region thickness on device performance is explored. Local features, such as the electric field and charge carrier concentrations, are also discussed.
Electron attachment to 14 halogenated alkenes and alkanes, 300-600 K
Authors: Shuman Nicholas S. , Friedman Jeffrey F. , Miller Thomas M. , Viggiano A. A.
Published: October 2012

Thermal electron attachment to 14 alkenes and alkanes with bromine, fluorine, and iodine substituents has been studied over the temperature range 300-600 K using a flowing-afterglow Langmuir-probe apparatus. Rate coefficients and anion products are reported, most for the first time. Among these were 3 isomers of C3F5Br and the 2 isomers of C3F7I. Four dibromide compounds were studied, all of which yield Br2− product in addition to Br− product. The results are analyzed using a statistical kinetic modeling approach, which is able to reproduce both attachment rate coefficients and product branching ratios within experimental uncertainty. The kinetic modeling indicates that factor of 2 differences in attachment rate coefficients to the isomeric species can be explained by subtle variations in the potential surfaces.
Mode coupling and fragile to strong transition in supercooled TIP4P water
Authors: Gallo P. , Rovere M.
Published: October 2012

We consider one of the most used model for water, the rigid four site TIP4P potential, and we study by molecular dynamics simulation the dynamical properties of the liquid upon supercooling. In the previous studies of the thermodynamics of the TIP4P model a liquid-liquid critical point (LLCP) located at the end of the coexistence between the low density liquid (LDL) and the high density liquid (HDL) of water was found. We present here the analysis of the self intermediate scattering functions in a large range of temperatures and densities and we show that the structural relaxation in the region of mild supercooling is in agreement with the predictions of the mode coupling theory. In the more deep supercooled region we observe that the α-relaxation time deviates from the mode coupling theory (MCT) trend and a crossover takes place from a fragile to a strong behavior upon crossing the Widom line emanating from the LLCP. The HDL and the LDL phases are associated with the fragile and the strong behavior, respectively.
Wave excitations of drifting two-dimensional electron gas under strong inelastic scattering
Authors: Korotyeyev V. V. , Kochelap V. A. , Varani L.
Published: October 2012

We have analyzed low-temperature behavior of two-dimensional electron gas in polar heterostructures subjected to a high electric field. When the optical phonon emission is the fastest relaxation process, we have found existence of collective wave-like excitations of the electrons. These wave-like excitations are periodic in time oscillations of the electrons in both real and momentum spaces. The excitation spectra are of multi-branch character with considerable spatial dispersion. There are one acoustic-type and a number of optical-type branches of the spectra. Their small damping is caused by quasi-elastic scattering of the electrons and formation of relevant space charge. Also there exist waves with zero frequency and finite spatial periods—the standing waves. The found excitations of the electron gas can be interpreted as synchronous in time and real space manifestation of well-known optical-phonon-transient-time-resonance. Estimates of parameters of the excitations for two polar heterostructures, GaN/AlGaN and ZnO/MgZnO, have shown that excitation frequencies are in THz-frequency range, while standing wave periods are in sub-micrometer region.
Dynamic mechanical analysis in La-based bulk metallic glasses: Secondary (β) and main (α) relaxations
Authors: Qiao J. C. , Pelletier J. M.
Published: October 2012

Relaxation behavior was investigated in typical La-based bulk metallic glasses by dynamic mechanical analysis, both in the isochronal and in the isothermal routes. Two relaxations were observed: the main relaxation (α), associated with the glass transition, and a secondary relaxation, at lower temperature or higher frequency. This secondary relaxation corresponds to the well known Johari-Goldstein (JG) β relaxation. Master curves can be obtained. The activation energy Eβ of β relaxation (about 1 eV) is in agreement with the empirical relation Eβ ≈ 26(±2) RTg. The high value of the activation energy Eα of the α relaxation (about 5 eV) indicates that this relaxation corresponds to correlated movements. The mechanism of JG β relaxation in metallic glasses is discussed.
Magnetization states of a spin-torque oscillator having perpendicular polarizer and planar free layer
Authors: Saida Daisuke , Nakamura Shiho
Published: October 2012

The dynamics and magnetization structures of spin-torque oscillators (STOs) consisting of a planar free layer and a perpendicular polarizer and having diameters of 10–100 nm are investigated by micromagnetic and macrospin simulations. For models having a diameter of 50 nm, the current-dependent frequency exhibited three oscillation modes: uniform oscillation, continuous oscillation with edge-localized core of the z-component of the magnetization (Mz component), and non-continuous rotation. The uniform oscillation mode and edge-localized oscillation mode are distinguished from each other by observing the frequencies of the Mz components. Further, we found that the oscillation frequency of the edge-localized mode changed in a step-like fashion under an external magnetic field, which was not observed in the uniform oscillation mode. The frequency in the edge-localized mode became saturated as the current increased toward the non-continuous mode, with the trajectory of the core gradually moving toward the center of the free layer. Finally, a vortex was formed and the oscillation stopped. The above behavior was observed in STOs having a diameter of not less than 30 nm.
Prediction of the thermal conductivity of ZnO nanobelts
Authors: Lahoucine Cherif Ould , Chantrenne Patrice
Published: October 2012

A prediction tool, based on a kinetic theory of gas model, previously developed for the thermal properties prediction of ZnO bulk crystal and nanostructures is used in order to be compared with existing literature results. As thermal conductivity measurement for nanostructures are seldom, the aim is to understand the validity range of the models and discuss their reliability. The estimation of the specific heat is in excellent agreement with data of bulk samples measured by other researchers. For the thermal conductivity, the comparison with other prediction tools and experimental results is done for nanowires and nanofilms. The agreement and the differences are discussed. It allows defining the complementarity of the prediction tools.
Fabrication and characterization of Bismuth-Cerium composite iron garnet epitaxial films for magneto optical applications
Authors: Chandra Sekhar M. , Singh Mahi R.
Published: October 2012

The BixCe3−xFe5O12 (x = 0.8) epitaxial films of high quality were grown by means of pulsed laser deposition on paramagnetic substrates of Gadolinium Gallium Garnet. We study the modifications of substitutions in the parent garnet Y3Fe5O12 that produces a higher magneto-optical response at communication wavelengths. These films displayed a strong in plane textures which are treated in argon as well as reduced atmosphere conditions. The elemental constituents of these films were confirmed by energy dispersive-X ray analysis, elastic recoil detection system, Rutherford backscattering spectroscopy, and X-ray photoelectron spectroscopy measurements. The transmittance spectra were measured and found these films exhibit good transmittance values. The transmittance-spectra were fitted with the theoretical model and the optical constants such as refractive index and absorption edge were evaluated. The highest (negative) Faraday rotation was found for these films treated in the environment of Ar + H2. A density matrix theory has been developed for the Faraday rotation and a good agreement between the theory and experiment is found. These epitaxial garnet films can be used in a wide range of frequencies from visible to infrared spectra making them ideal for many magneto optical applications. Therefore, these films may overcome many issues in fabricating all optical isolators which is the viable solution for integrated photonics.
The cylindrical magnetic Rayleigh-Taylor instability for viscous fluids
Authors: Chambers K. , Forbes L. K.
Published: October 2012

This paper considers a cylindrical Rayleigh-Taylor instability, in which a heavy fluid surrounds a light fluid, and gravity is directed radially inwards. A massive object is located at the centre of the light fluid, and it behaves like a line dipole both for fluid flow and magnetic field strength. The initially circular interface between the two conducting fluids evolves into plumes, dependent on the magnetic and fluid dipole strengths and the nature of the initial disturbance to the interface. A spectral method is presented to solve the time-dependent interface shapes, and results are presented and discussed. Bipolar solutions are possible, and these are of particular relevance to astrophysics. The solutions obtained resemble structures of some HII regions and nebulae.
Incorporation of plug in hybrid electric vehicle in the reactive power market
Authors: Feshki Farahani H. , Shayanfar H. A. , Ghazizadeh M. S.
Published: October 2012

This paper incorporates plug in hybrid electric vehicle (PHEV) in the reactive power market. The PHEV capability curve is first extracted considering the operation limit of PHEV. In order to offer price in the reactive power market, expected payment function (EPF) of PHEV is then proposed based on its capability curve. The reactive power market is cleared by minimization of total payment function (TPF). TPF is in fact the amount of dollars paid to the accepted synchronous generator and PHEVs in the reactive power market. Furthermore, the uncertainty of PHEVs, synchronous generators, as well as the uncertainty of load is taken into account in the proposed framework. The effectiveness of the proposed reactive power market is studied based on a 17-node microgrid in both cases of with and without consideration of PHEVs, synchronous generators, and load uncertainties.
A test of systematic coarse-graining of molecular dynamics simulations: Thermodynamic properties
Authors: Fu Chia-Chun , Kulkarni Pandurang M. , Scott Shell M. , Gary Leal L.
Published: October 2012

Coarse-graining (CG) techniques have recently attracted great interest for providing descriptions at a mesoscopic level of resolution that preserve fluid thermodynamic and transport behaviors with a reduced number of degrees of freedom and hence less computational effort. One fundamental question arises: how well and to what extent can a “bottom-up” developed mesoscale model recover the physical properties of a molecular scale system? To answer this question, we explore systematically the properties of a CG model that is developed to represent an intermediate mesoscale model between the atomistic and continuum scales. This CG model aims to reduce the computational cost relative to a full atomistic simulation, and we assess to what extent it is possible to preserve both the thermodynamic and transport properties of an underlying reference all-atom Lennard-Jones (LJ) system. In this paper, only the thermodynamic properties are considered in detail. The transport properties will be examined in subsequent work. To coarse-grain, we first use the iterative Boltzmann inversion (IBI) to determine a CG potential for a (1-ϕ)N mesoscale particle system, where ϕ is the degree of coarse-graining, so as to reproduce the radial distribution function (RDF) of an N atomic particle system. Even though the uniqueness theorem guarantees a one to one relationship between the RDF and an effective pairwise potential, we find that RDFs are insensitive to the long-range part of the IBI-determined potentials, which provides some significant flexibility in further matching other properties. We then propose a reformulation of IBI as a robust minimization procedure that enables simultaneous matching of the RDF and the fluid pressure. We find that this new method mainly changes the attractive tail region of the CG potentials, and it improves the isothermal compressibility relative to pure IBI. We also find that there are optimal interaction cutoff lengths for the CG system, as a function of ϕ, that are required to attain an adequate potential while maintaining computational speedup. To demonstrate the universality of the method, we test a range of state points for the LJ liquid as well as several LJ chain fluids.
Fredholm's equations for subwavelength focusing
Authors: Velázquez-Arcos J. M.
Published: October 2012

Subwavelength focusing (SF) is a very useful tool that can be carried out with the use of left hand materials for optics that involve the range of the microwaves. Many recent works have described a successful alternative procedure using time reversal methods. The advantage is that we do not need devices which require the complicated manufacture of left-hand materials; nevertheless, the theoretical mathematical bases are far from complete because before now we lacked an adequate easy-to-apply frame. In this work we give, for a broad class of discrete systems, a solid support for the theory of electromagnetic SF that can be applied to communications and nanotechnology. The very central procedure is the development of vector-matrix formalism (VMF) based on exploiting both the inhomogeneous and homogeneous Fredholm's integral equations in cases where the last two kinds of integral equations are applied to some selected discrete systems. To this end, we first establish a generalized Newmann series for the Fourier transform of the Green's function in the inhomogeneous Fredholm's equation of the problem. Then we go from an integral operator equation to a vector-matrix algebraic one. In this way we explore the inhomogeneous case and later on also the very interesting one about the homogeneous equation. Thus, on the one hand we can relate in a simple manner the arriving electromagnetic signals with those at their sources and we can use them to perform a SF. On the other hand, we analyze the homogeneous version of the equations, finding resonant solutions that have analogous properties to their counterparts in quantum mechanical scattering, that can be used in a proposed very powerful way in communications. Also we recover quantum mechanical operator relations that are identical for classical electromagnetics. Finally, we prove two theorems that formalize the relation between the theory of Fredholm's integral equations and the VMF we present here.