bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of a new hyperbranched‐linear‐hyperbranched triblock copolymer and its use as a chemical modifier for the cationic photo and thermal curing of epoxy resins
Authors: Foix D. , Ramis X. , Sangermano M. , Serra A.
Published: December 2011

A new hyperbranched‐linear‐hyperbranched polymer was prepared in a one pot process by reaction of 4,4‐bis(4‐hydroxyphenyl)valeric acid and poly(ethylene glycol) (HPH). After characterization by 1H and 13C NMR, SEC, DSC, and TGA, this polymer was used, in proportions of 5, 10, and 15 phr, as a chemical modifier in the UV and thermal cationic curing of 3,4‐epoxycyclohexylmethyl‐3′,4′‐epoxycyclohexyl carboxylate epoxy resin. The curing process was studied by calorimetry, demonstrating the accelerating effect of the hydroxyl groups present in HPH's structure. The morphology of the resulting thermosets depended on the curing system used, as demonstrated by FE‐SEM microscopy, but in both cases phase separation occurred. Thermosets obtained by thermal curing presented lower thermal stability than UV‐cured materials. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Tunable capacitive inter‐dot coupling in a bilayer graphene double quantum dot
Authors: Fringes Stefan , Volk Christian , Terrés Bernat , Dauber Jan , Engels Stephan , Trellenkamp Stefan , Stampfer Christoph
Published: December 2011

We report on a double quantum dot which is formed in a width‐modulated etched bilayer graphene nanoribbon. A number of lateral graphene gates enable us to tune the quantum dot energy levels and the tunneling barriers of the device over a wide energy range. Charge stability diagrams and in particular individual triple point pairs allow to study the tunable capacitive inter‐dot coupling energy as well as the spectrum of the electronic excited states on a number of individual triple points. We extract a mutual capacitive inter‐dot coupling in the range of 2–6 meV and an inter‐dot tunnel coupling on the order of 1.5 µeV. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Assimilation of water‐vapour airborne lidar observations: impact study on the COPS precipitation forecasts
Authors: Bielli S. , Grzeschik M. , Richard E. , Flamant C. , Champollion C. , Kiemle C. , Dorninger M. , Brousseau P.
Published: December 2011

The Convective and Orographically‐driven Precipitation Study (COPS) carried out in summer 2007 over northeastern France and southwestern Germany provided a fairly comprehensive description of the low‐troposphere water‐vapour field, thanks in particular to the deployment of two airborne differential absorption lidar systems. These lidar observations were assimilated using the 3D‐Var assimilation system of the Application of Research to Operations at MEsoscale (AROME) numerical weather prediction mesoscale model. The assimilation was carried out for the period 4 July–3 August by running a three‐hour forward intermittent assimilation cycle. First, the impact of the lidar observations was assessed by comparing the analyses with a set of more than 200 independent soundings. The lidar observations were found to have a positive impact on the analyses by reducing the dry bias in the first 500 m above ground level and by diminishing the root‐mean‐square error by roughly 15% in the first km. Then the impact of the lidar observations was assessed by comparing the precipitation forecasts (obtained with and without the lidar observations for the period 15 July–2 August) with the gridded precipitation observations provided by the Vienna Enhanced Resolution Analysis. In general, the impact was found to be positive but not significant for the 24 h precipitation and positive and significant for the 6 h precipitation, with an improvement lasting up to 24 h. Some selected case studies show that the improvement was obtained through a better depiction of convection initiation or through a more accurate positioning of the precipitation systems. Copyright © 2011 Royal Meteorological Society
X‐ray compositional microanalysis and diffraction studies of Haltern 70 amphorae sherds
Authors: Costa B. F. O. , Silva A. J. M. , Ramalho A. , Pereira G. , Ramos Silva M.
Published: December 2011

Haltern 70 amphorae sherds from excavations at Castro do Vieito, north of Portugal, and amphora sherds found inside kilns from Baetican and Lusitanian provinces of the Roman Empire are studied by X‐ray diffraction and X‐ray fluorescence (scanning electron microscopy/energy‐dispersive X‐ray spectroscopy). The comparison of these results is also made. The chosen methods give the possibility to determine element composition of the pottery, which is already fired, and thus try to single out the match of the two series of amphorae sherds. From the chemical analysis, the Castro do Vieito sherds are very homogeneous, but this is not the case of the sherds collected in the overall kilns. Vieito sherds have nearly no Na content, and Al content is about 9 wt% as well as samples from kilns from Medium Guadalquivir, Cadiz Bay and Guadiana estuary. Ca content in Vieito sherds are about 1 wt% and in amphorae kilns sherds except in the case of samples from Puerto Real and Arva, where Ca concentration is about 5 wt% and Lebrija and Pinguele where Ca concentration is about 10 wt%. The main conclusion drawn is that the provenance of Castro do Vieito sherds seems to be confirmed as being from Baetica (actual Andaluzia) because of the aforementioned reasons together with the fact that the elements found in the sherds are the same as the ones known to belong to raw materials from Baetica. Copyright © 2011 John Wiley & Sons, Ltd.
A mixture of oleic, erucic and conjugated linoleic acids modulates cerebrospinal fluid inflammatory markers and improve somatosensorial evoked potential in X‐linked adrenoleukodystrophy female carriers
Authors: Cappa Marco , Bizzarri Carla , Petroni Anna , Carta Gianfranca , Cordeddu Lina , Valeriani Massimiliano , Vollono Catello , De Pasquale Loredana , Blasevich Milena , Banni Sebastiano
Published: December 2011

X−linked adrenoleukodystrophy is a rare inherited demyelinating disorder characterized by an abnormal accumulation of very long chain fatty acids, mainly hexacosanoic acid (26:0), due to a mutation of the gene encoding for a peroxisomal membrane protein. The only available, and partially effective, therapeutic treatment consists of dietary intake of a 4:1 mixture of triolein and trierucin, called Lorenzo's oil (LO), targeted to inhibit the elongation of docosanoic acid (22:0) to 26:0. In this study we tested whether, besides inhibiting elongation, an enhancement of peroxisomal beta oxidation induced by conjugated linoleic acid (CLA), will improve somatosensory evoked potentials and modify inflammatory markers in adrenoleukodystrophy females carriers. We enrolled five heterozygous women. They received a mixture of LO (40 g/day) with CLA (5 g/day) for 2 months. The therapeutic efficacy was evaluated by the means of plasma levels of 26:0, 26:0/22:0 ratio, modification of cerebrospinal fluid (CSF) inflammatory markers and somatosensory evoked potentials. Changes of fatty acid profile, and in particular CLA incorporation, were also evaluated in CSF and plasma. The results showed that CLA promptly passes the blood brain barrier and the mixture was able to lower both 26:0 and 26:0/22:0 ratio in plasma. The mixture improved somatosensory evoked potentials, which were previously found unchanged or worsened with dietary LO alone, and reduced IL‐6 levels in CSF in three out of five patients. Our data suggest that the synergic activity of CLA and LO, by enhancing peroxisomal beta‐oxidation and preventing 26:0 formation, improves the somatosensory evoked potentials and reduces neuroinflammation.
The diagnosis and management of ovarian hyperstimulation syndrome
Authors: Shmorgun Doron , Claman Paul , Gysler Mathias , Hemmings Robert , Cheung Anthony P. , Goodrow Gwendolyn J. , Hughes Edward G. , Min Jason K. , Roberts Jeff , Senikas Vyta , Wong Benjamin Chee‐Man , Young David C.
Published: December 2011

Objective

To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its diagnosis and clinical management.

Outcomes

These guidelines will assist in the early recognition and management of ovarian hyperstimulation. Early recognition and prompt systematic supportive care will help avert poor outcomes.

Evidence

Medline, Embase, and the Cochrane database were searched for relevant articles, using the key words “ovarian hyperstimulation syndrome” and “gonadotropins,” and guidelines created by other professional societies were reviewed.

Values

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table 1).
How we relate to brands: Psychological and neurophysiological insights into consumer–brand relationships
Authors: Reimann Martin , Castaño Raquel , Zaichkowsky Judith , Bechara Antoine
Published: December 2011

In three experiments, this research provides new insights into branding by studying the psychological and neurophysiological mechanisms of how consumers relate to their beloved brands. The authors propose that emotional arousal decreases over the brand relationship span, while inclusion of the brand into the self increases over time. Results of experiment 1 indicate greater self‐reported emotional arousal for recently formed brand relationships, as well as decreased emotional arousal and increased inclusion of close brands over time. Additionally, the moderating role of usage frequency of the brand brings out an interesting nuance of the way these effects operate. Experiment 2 measures skin conductance responses and reveals increased emotional arousal for recently formed close relationships but not for established close brand relationships, corroborating the results based on self‐reported data. In experiment 3, a functional magnetic resonance imaging study reveals an association between established close relationships and activation of the insula, a brain area previously found to be a crucial mechanism in diverse but related psychological phenomena such as urging, addiction, loss aversion, and interpersonal love.
Application and Performance of Two Stroke Outcome Prediction Models in a Chinese Population
Authors: Li Wen‐Juan , Gao Zhi‐Yu , He Yang , Liu Guang‐Zhi , Gao Xu‐Guang
Published: December 2011

Objective

To apply and examine the performance of 2 acute stroke outcome prediction models, the Six Simple Variable Model (SSV model) and the One‐Year Mortality Model (OYM model), in patients in China who had either a cerebral infarction or a cerebral hemorrhage.

Design

An observational study that used both retrospective and prospective study methods.

Setting

A regional acute care facility in China.

Participants

Two hundred and forty‐eight consecutive patients who had an acute stroke who were admitted to the hospital between October 2007 and March 2009.

Interventions

Not applicable.

Main Outcome Measures

Survival and daily activity independence 6 months after a stroke and 1‐year mortality.

Results

The study sample had a mean age of 68.6 years (standard deviation, 11.1); 52.8% of the subjects were men, 66.5% had a cerebral infarction, and 33.5% had a cerebral hemorrhage. In the cohort, 107 patients (43.1%) achieved daily activity independence at 6‐month follow‐up, and 52 patients (21.0%) had died within 1 year. The area under the receiver operating characteristic curve (ROC) was 0.966 (0.935‐0.998) for patients who had a cerebral infarction and 0.859 (0.766‐0.952) for patients who had a cerebral hemorrhage in the prediction of 6‐month survival and daily activity independence with use of the SSV model. The area under the ROC curve was 0.894 (0.846‐0.965) for patients who had a cerebral infarction and 0.937 (0.904‐0.988) for patients who had a cerebral hemorrhage in the prediction of 1‐year mortality when the OYM model was used.

Conclusions

Both the SSV and OYM prognostic models can be used for function and mortality outcome prediction for patients in China who have had a stroke. Variation existed in the precision of prediction between patients who had a cerebral infarction and those who had a cerebral hemorrhage. Other potential factors influencing functional recovery and mortality after stroke must be considered in outcome prediction.
Real-time sentence processing in children with specific language impairment: The contribution of lexicosemantic, syntactic, and world-knowledge information
Authors: PIZZIOLI FABRIZIO , SCHELSTRAETE MARIE-ANNE
Published: December 2011

The present study investigated how lexicosemantic information, syntactic information, and world knowledge are integrated in the course of oral sentence processing in children with specific language impairment (SLI) as compared to children with typical language development. A primed lexical-decision task was used where participants had to make a lexical decision on the last word of a sentence. Thirty-nine children were tested: 13 children with SLI, 13 younger children matched on receptive vocabulary, and 13 age-matched children. We manipulated (a) the semantic fit between the target and the prime sentence, (b) the syntactic structure of the prime (syntactic vs. asyntactic), and (c) the lexical association between the target word and the prime. Despite being slower overall, children with SLI showed a significant priming effect. Syntactic information had a similar impact on thematic integration in control children and children with SLI, although the latter were more sensitive to lexicosemantic association and world knowledge than control groups. In addition, children with SLI appeared to use semantic information even when the sentence was asyntactic. The results suggest thematic integration problems in SLI: syntactic and semantic information contribute independently to the thematic structure but are not integrated to generate the emerging higher order representation.
Stimulus variability and perceptual learning of nonnative vowel categories
Authors: BROSSEAU-LAPRÉ FRANÇOISE , RVACHEW SUSAN , CLAYARDS MEGHAN , DICKSON DANIEL
Published: December 2011

English-speakers' learning of a French vowel contrast (/ə/–/ø/) was examined under six different stimulus conditions in which contrastive and noncontrastive stimulus dimensions were varied orthogonally to each other. The distribution of contrastive cues was varied across training conditions to create single prototype, variable far (from the category boundary), and variable close (to the boundary) conditions, each in a single talker or a multiple talker version. The control condition involved identification of gender appropriate grammatical elements. Pre- and posttraining measures of vowel perception and production were obtained from each participant. When assessing pre- to posttraining changes in the slope of the identification functions, statistically significant training effects were observed in the multiple voice far and multiple voice close conditions.
THE MEANING OF LIFE
Authors: Law Stephen
Published: December 2011

According to some, questions about the meaning of life are inextricably bound up with questions about God and religion. Without God, it is suggested, humanity amounts to little more than a dirty smudge on a ball of rock lost in an incomprehensively vast universe that will eventually bare no trace of us having ever existed, and which will itself collapse into nothingness. So why bother getting out of bed in the morning? If there is a God, on the other hand, then we inhabit a universe made for us, by a God who loves us, and who has given us a divine purpose. That fills our lives meaning.
The Power of Sample Return Missions - Stardust and Hayabusa
Authors: Sandford Scott A.
Published: December 2011

Sample return missions offer opportunities to learn things about other objects in our Solar System (and beyond) that cannot be determined by observations using in situ spacecraft. This is largely because the returned samples can be studied in terrestrial laboratories where the analyses are not limited by the constraints - power, mass, time, precision, etc. - imposed by normal spacecraft operations. In addition, the returned samples serve as a scientific resource that is available far into the future; the study of the samples can continue long after the original spacecraft mission is finished. This means the samples can be continually revisited as both our scientific understanding and analytical techniques improve with time.

These advantages come with some additional difficulties, however. In particular, sample return missions must deal with the additional difficulties of proximity operations near the objects they are to sample, and they must be capable of successfully making a round trip between the Earth and the sampled object. Such missions therefore need to take special precautions against unique hazards and be designed to successfully complete relatively extended mission durations.

Despite these difficulties, several recent missions have managed to successfully complete sample returns from a number of Solar System objects. These include the Stardust mission (samples from Comet 81P/Wild 2), the Hayabusa mission (samples from asteroid 25143 Itokawa), and the Genesis mission (samples of solar wind). This paper will review the advantages and difficulties of sample return missions in general and will summarize some key findings of the recent Stardust and Hayabusa missions.
Observations of Molecules in High Redshift Galaxies
Authors: Knudsen Kirsten Kraiberg
Published: December 2011

I present an overview of the molecular gas observations in high redshift galaxies. This field has seen tremendous progress in the past few years, with an increased number of detections of other molecules than CO. The molecular line observations are done towards different classes of massive starbursts, including submillimeter galaxies, quasars, and massive gas-rich disks. I will highlight results of detections of HCN, HCO+, and other small molecules, as well as the Spitzer detections of PAHs. Additionally, I will discuss about the excitation of CO and other species in the high-z galaxies and put this in the context of new telescopes such as ALMA.
Extragalactic Line Surveys
Authors: Martín Sergio
Published: December 2011

40 years have passed since the first molecular detection outside our Galaxy. Since then, our knowledge on the distribution, kinematics and composition of the molecular material in the extragalactic ISM has built up significantly based not only on the carbon monoxide observations but also in the more than 50 molecular species detected. In particular, line surveys have been proven to be excellent tools to study the chemical composition in the nuclei of galaxies. Such studies have been favored by the increasing instantaneous bandwidth of current mm and sub-mm facilities. Here I will summarize the highlights of extragalactic molecular spectroscopy, mostly focusing in the results from molecular line surveys published in the last few years as well as the aims of still ongoing projects.
How Can We Use Complete Experimental Catalogs in the Complex Spectra Limit?
Authors: De Lucia Frank C. , Fortman Sarah M. , Medvedev Ivan R. , Neese Christopher F.
Published: December 2011

There is a broad consensus that many, if not most, of the unidentified spectral lines in astrophysical spectra are due to transitions in excited vibrational states of a relatively small number of molecules, the astrophysical weeds. For these unidentified lines, it is somewhat less well understood that the spectroscopic effort required to characterize them in the traditional quantum mechanical catalog approach is substantially larger because of significant perturbations. We have previously discussed a new experimental approach that addresses this challenge. This approach is based on the analysis of many complete, intensity-calibrated spectra taken over a range of temperatures. However, the spectroscopic completeness of this approach results in a much larger database. These data can be transfer to the astrophysical community in a variety of ways, but because an order of magnitude larger number of lines is included, consideration must be given to implementation strategies.
The Development and Evaluation of an Educational Placement Screener for Youths in Pretrial Detention
Authors: Hart Lesley , Naples Adam , Chapman John , Chart Hilary , D’Amaddio Amy , Foley-Geib Catherine , Macomber Donna , Skiba Thomas , Tan Mei , Grigorenko Elena L.
Published: December 2011

This report provides an overview of the development and preliminary evaluation of an educational placement screener for use in short-term juvenile detention facilities. The screener is designed to gauge levels of competence in reading (at the word and text level) and mathematics for juveniles in grades 3–12, and to serve as a rapid assessment device for subsequent educational placement within 48 h of admission. The psychometric properties of the screener were evaluated in a sample of 1,078 youths in detention and 157 youths in the community. The importance of the availability of easy-to-administer assessment devices that can accurately capture the level of academic functioning of youths in detention is discussed within the larger context of meeting the educational rights and needs of juvenile delinquents.
Observations and simulations of formation of broad plasma depletions through merging process
Authors: Huang Chao‐Song , Retterer J. M. , de La Beaujardiere O. , Roddy P. A. , Hunton D. E. , Ballenthin J. O. , Pfaff R. F.
Published: December 2011

Broad plasma depletions in the equatorial ionosphere near dawn are region in which the plasma density is reduced by 1–3 orders of magnitude over thousands of kilometers in longitude. This phenomenon is observed repeatedly by the Communication/Navigation Outage Forecasting System (C/NOFS) satellite during deep solar minimum. The plasma flow inside the depletion region can be strongly upward. The possible causal mechanism for the formation of broad plasma depletions is that the broad depletions result from merging of multiple equatorial plasma bubbles. The purpose of this study is to demonstrate the feasibility of the merging mechanism with new observations and simulations. We present C/NOFS observations for two cases. A series of plasma bubbles is first detected by C/NOFS over a longitudinal range of 3300–3800 km around midnight. Each of the individual bubbles has a typical width of ∼100 km in longitude, and the upward ion drift velocity inside the bubbles is 200–400 m s−1. The plasma bubbles rotate with the Earth to the dawn sector and become broad plasma depletions. The observations clearly show the evolution from multiple plasma bubbles to broad depletions. Large upward plasma flow occurs inside the depletion region over 3800 km in longitude and exists for ∼5 h. We also present the numerical simulations of bubble merging with the physics‐based low‐latitude ionospheric model. It is found that two separate plasma bubbles join together and form a single, wider bubble. The simulations show that the merging process of plasma bubbles can indeed occur in incompressible ionospheric plasma. The simulation results support the merging mechanism for the formation of broad plasma depletions.
Multiscale InSAR Time Series (MInTS) analysis of surface deformation
Authors: Hetland E. A. , Musé P. , Simons M. , Lin Y. N. , Agram P. S. , DiCaprio C. J.
Published: December 2011

We present a new approach to extracting spatially and temporally continuous ground deformation fields from interferometric synthetic aperture radar (InSAR) data. We focus on unwrapped interferograms from a single viewing geometry, estimating ground deformation along the line‐of‐sight. Our approach is based on a wavelet decomposition in space and a general parametrization in time. We refer to this approach as MInTS (Multiscale InSAR Time Series). The wavelet decomposition efficiently deals with commonly seen spatial covariances in repeat‐pass InSAR measurements, since the coefficients of the wavelets are essentially spatially uncorrelated. Our time‐dependent parametrization is capable of capturing both recognized and unrecognized processes, and is not arbitrarily tied to the times of the SAR acquisitions. We estimate deformation in the wavelet‐domain, using a cross‐validated, regularized least squares inversion. We include a model‐resolution‐based regularization, in order to more heavily damp the model during periods of sparse SAR acquisitions, compared to during times of dense acquisitions. To illustrate the application of MInTS, we consider a catalog of 92 ERS and Envisat interferograms, spanning 16 years, in the Long Valley caldera, CA, region. MInTS analysis captures the ground deformation with high spatial density over the Long Valley region.
Continental‐scale water and energy flux analysis and validation for the North American Land Data Assimilation System project phase 2 (NLDAS‐2): 1. Intercomparison and application of model products
Authors: Xia Youlong , Mitchell Kenneth , Ek Michael , Sheffield Justin , Cosgrove Brian , Wood Eric , Luo Lifeng , Alonge Charles , Wei Helin , Meng Jesse , Livneh Ben , Lettenmaier Dennis , Koren Victor , Duan Qingyun , Mo Kingtse , Fan Yun , Mocko David
Published: December 2011

Results are presented from the second phase of the multiinstitution North American Land Data Assimilation System (NLDAS‐2) research partnership. In NLDAS, the Noah, Variable Infiltration Capacity, Sacramento Soil Moisture Accounting, and Mosaic land surface models (LSMs) are executed over the conterminous U.S. (CONUS) in realtime and retrospective modes. These runs support the drought analysis, monitoring and forecasting activities of the National Integrated Drought Information System, as well as efforts to monitor large‐scale floods. NLDAS‐2 builds upon the framework of the first phase of NLDAS (NLDAS‐1) by increasing the accuracy and consistency of the surface forcing data, upgrading the land surface model code and parameters, and extending the study from a 3‐year (1997–1999) to a 30‐year (1979–2008) time window. As the first of two parts, this paper details the configuration of NLDAS‐2, describes the upgrades to the forcing, parameters, and code of the four LSMs, and explores overall model‐to‐model comparisons of land surface water and energy flux and state variables over the CONUS. Focusing on model output rather than on observations, this study seeks to highlight the similarities and differences between models, and to assess changes in output from that seen in NLDAS‐1. The second part of the two‐part article focuses on the validation of model‐simulated streamflow and evaporation against observations. The results depict a higher level of agreement among the four models over much of the CONUS than was found in the first phase of NLDAS. This is due, in part, to recent improvements in the parameters, code, and forcing of the NLDAS‐2 LSMs that were initiated following NLDAS‐1. However, large inter‐model differences still exist in the northeast, Lake Superior, and western mountainous regions of the CONUS, which are associated with cold season processes. In addition, variations in the representation of sub‐surface hydrology in the four LSMs lead to large differences in modeled evaporation and subsurface runoff. These issues are important targets for future research by the land surface modeling community. Finally, improvement from NLDAS‐1 to NLDAS‐2 is summarized by comparing the streamflow measured from U.S. Geological Survey stream gauges with that simulated by four NLDAS models over 961 small basins.
Europa's icy bright plains and dark linea: Exogenic and endogenic contributions to composition and surface properties
Authors: Dalton J. B. , Shirley J. H. , Kamp L. W.
Published: December 2011

We compare linear spectral modeling solutions yielding surface abundance estimates and water ice grain size information from low‐noise Galileo Near‐Infrared Mapping Spectrometer (NIMS) observations for three widely spaced locations on Europa. Bright equatorial plains on the orbital leading side are dominated by fine‐grained (∼50–75 μm) water ice (>80 wt%). This area shows a low abundance of hydrated salts and statistically insignificant amounts of hydrated sulfuric acid. A midlatitude northern hemisphere location on the trailing side exhibits strikingly different surface composition and properties for similar terrain. The modeled abundance of hydrated sulfuric acid exceeds 40% here; large‐grained water ice (∼250 μm diameter) dominates the ice grain size distribution. A third location at high southern latitudes on the leading side exhibits high abundances of water ice (>67%) and no detectable sulfuric acid hydrate. Water ice grain sizes here are intermediate between those of the other locations, at 75–100 μm. We resolve compositional differences between the darkest materials (at visible wavelengths) and the most hydrated materials (as evidenced by the distortion of water ice absorption bands) on Europa's leading side. Distinctive water ice grain size distributions are associated with visibly dark materials in all three locations. Our results help distinguish between exogenic and endogenic influences on Europa's present‐day surface composition. The results are consistent with migration and redeposition of sputtered water ice molecules from trailing to leading side locations.
Nitrative Stress in Cerebral Endothelium is Mediated by mGluR5 in Hyperhomocysteinemia
Authors: Mayo Jamie N , Beard Richard S , Price Tulin O , Chen Cheng-Hung , Erickson Michelle A , Ercal Nuran , Banks William A , Bearden Shawn E
Published: December 2011

Hyperhomocysteinemia (HHcy) disrupts nitric oxide (NO) signaling and increases nitrative stress in cerebral microvascular endothelial cells (CMVECs). This is mediated, in part, by protein nitrotyrosinylation (3-nitrotyrosine; 3-NT) though the mechanisms by which extracellular homocysteine (Hcy) generates intracellular 3-NT are unknown. Using a murine model of mild HHcy ( cbs+/– mouse), we show that 3-NT is significantly elevated in cerebral microvessels with concomitant reductions in serum NO bioavailability as compared with wild-type littermate controls ( cbs+/+). Directed pharmacology identified a receptor-dependent mechanism for 3-NT formation in CMVECs. Homocysteine increased expression of inducible NO synthase (iNOS) and formation of 3-NT, both of which were blocked by inhibition of metabotropic glutamate receptor-5 (mGluR5) with the specific antagonist 2-methyl-6-(phenylethynyl) pyridine hydrochloride. Activation of mGluR5 is both sufficient and necessary to drive the nitrative stress because direct activation using the mGluR5-specific agonist (RS)-2-chloro-5-hydroxyphenylglycine also increased iNOS expression and 3-NT formation while knockdown of mGluR5 receptor expression by short hairpin RNA (shRNA) blocked their increase in response to Hcy. Nitric oxide derived from iNOS was required for Hcy-mediated formation of 3-NT because the effect was blocked by 1400 W. These results provide the first evidence for a receptor-dependent process that explains how plasma Hcy levels control intracellular nitrative stress in cerebral microvascular endothelium.
Regulation and function of the RSK family of protein kinases
Authors: Romeo Yves , Zhang Xiaocui , Roux Philippe P.
Published: December 2011

The RSK (90 kDa ribosomal S6 kinase) family comprises a group of highly related serine/threonine kinases that regulate diverse cellular processes, including cell growth, proliferation, survival and motility. This family includes four vertebrate isoforms (RSK1, RSK2, RSK3 and RSK4), and single family member orthologues are also present in Drosophila and Caenorhabditis elegans. The RSK isoforms are downstream effectors of the Ras/ERK (extracellular-signal-regulated kinase) signalling pathway. Significant advances in the field of RSK signalling have occurred in the past few years, including several new functions ascribed to the RSK isoforms, the discovery of novel protein substrates and the implication of different RSK isoforms in cancer. Collectively, these new findings increase the diversity of biological functions regulated by RSK, and highlight potential new directions of research. In the present paper, we review the structure, expression and activation mechanisms of the RSK isoforms, and discuss their physiological roles on the basis of established substrates and recent discoveries.
Effective Therapy of Insulinoma by Using Long-Acting Somatostatin Analogue. A Case Report and Literature Review
Authors: Jawiarczyk A. , Bolanowski M. , Syrycka J. , Bednarek-Tupikowska G. , Kałużny M. , Kołodziejczyk A. , Domosławski P.
Published: December 2011

We are reporting a case of 68-year-old woman with insulinoma, after a non-successful tumor surgery and a long-term diazoxide treatment. She had a lot of hypoglycemia cases, and a weight gain of 50 kg. An abdominal CT scan demonstrated a tumor 28 mm in the diameter, in the head of the pancreas. The patient did not agree for the repeated insulinoma surgery. Furthermore, we found a lesion in the left adrenal gland (14 mm in the diameter) and in the right lung (8 mm in the diameter). Pheochromocytoma was diagnosed on the basis of hypertension, elevated levels of normetanephrine in the 24-h urine collection, and an elevated level of norepinephrine in a plasma sample. After the left adrenal gland removal we observed lower blood pressure. Since we had revealed the presence of somatostatin receptors by the somatostatin receptors scintigraphy, we decided to control hypoglycemia by a monthly subcutaneous administration of the long-acting lanreotide. Because of higher glucose levels (300–400 mg/dl) we started an intense insulin therapy. Nowadays, the patient feels better, she has lost 20 kg of her body weight, and we have observed normal blood glucose levels during the long-term lanreotide treatment. We have noticed neither side effects nor hypoglycemic episodes and we have reduced the dose of insulin. The presented case can be an evidence of the effective treatment of the pancreatic neuroendocrine tumor of insulinoma type, with somatostatin analogue.
Diabetes Mellitus and Incidence and Mortality of Gastric Cancer: A Meta-Analysis
Authors: Tian T. , Zhang L. , Ma X. , Zhou J. , Shen J.
Published: December 2011

Epidemiologic studies have examined the possible associations between diabetes mellitus (DM) and gastric cancer (GC), but the results are inconclusive. We conducted a meta-analysis to assess the evidence regarding the associations between diabetes and incidences of, or mortality from, gastric cancer.

PubMed, Embase and Web of Science were searched up to Oct 20, 2011. We identified studies that included effects estimates with 95% confidence intervals (CIs) of the associations between GC and diabetes. Summary RRs for the GC incidence and mortality were calculated using random-effects model; subgroup analyses were also performed. Heterogeneity among studies was examined using Q and I2 statistics.

A total of 7 case-control and 18 cohort studies met the inclusion criteria. The summary RR showed a slightly statistical link between history of DM and GC incidence (RR=1.11, 95% CI: 1.00–1.24, p=0.045, I2=79.5%). In the subgroup analyses, a positive association was noted among the studies conducted in Asia (summary RR=1.19, 95% CI: 1.07–1.32, I2=29.8%). Additionally, slight associations between DM and GC were observed by pooling the data of type 2 DM, cohort studies and the studies controlling more confounders, respectively. Furthermore, mortality from GC with diabetes was increased compared with individuals without diabetes (summary RR=1.29, 95% CI: 1.04–1.59). No publication bias was found.

Individuals with diabetes have an increased risk of developing gastric cancer, and are positively associated with gastric cancer mortality. Large better-designed cohort studies are needed to verify this conclusion.
Is the Smagorinsky coefficient sensitive to uncertainty in the form of the energy spectrum?
Authors: Meldi M. , Lucor D. , Sagaut P.
Published: December 2011

We investigate the influence of uncertainties in the shape of the energy spectrum over the Smagorinsky [“General circulation experiments with the primitive equations. I: The basic experiment,” Mon. Weather Rev. 91(3), 99 (1963)] subgrid scale model constant CS: the analysis is carried out by a stochastic approach based on generalized polynomial chaos. The free parameters in the considered energy spectrum functional forms are modeled as random variables over bounded supports: two models of the energy spectrum are investigated, namely, the functional form proposed by Pope [Turbulent Flows (Cambridge University Press, Cambridge, 2000)] and by Meyers and Meneveau [“A functional form for the energy spectrum parametrizing bottleneck and intermittency effects,” Phys. Fluids 20(6), 065109 (2008)]. The Smagorinsky model coefficient, computed from the algebraic relation presented in a recent work by Meyers and Sagaut [“On the model coefficients for the standard and the variational multi-scale Smagorinsky model,” J. Fluid Mech. 569, 287 (2006)], is considered as a stochastic process and is described by numerical tools streaming from the probability theory. The uncertainties are introduced in the free parameters shaping the energy spectrum in correspondence to the large and the small scales, respectively. The predicted model constant is weakly sensitive to the shape of the energy spectrum when large scales uncertainty is considered: if the large-eddy simulation (LES) filter cut is performed in the inertial range, a significant probability to recover values lower in magnitude than the asymptotic Lilly-Smagorinsky model constant is recovered. Furthermore, the predicted model constant occurrences cluster in a compact range of values: the correspondent probability density function rapidly drops to zero approaching the extremes values of the range, which show a significant sensitivity to the LES filter width. The sensitivity of the model constant to uncertainties propagated in the small scales of the energy spectrum is noticeable and a wide range of possible Smagorinsky model constant values is observed, if the LES filter cut is performed close to the dissipation region.
Br2 molecular elimination in photolysis of (COBr)2 at 248 nm by using cavity ring-down absorption spectroscopy: A photodissociation channel being ignored
Authors: Wu Chia-Ching , Lin Hsiang-Chin , Chang Yuan-Bin , Tsai Po-Yu , Yeh Yu-Ying , Fan He , Lin King-Chuen , Francisco J. S.
Published: December 2011

A primary dissociation channel of Br2 elimination is detected following a single-photon absorption of (COBr)2 at 248 nm by using cavity ring-down absorption spectroscopy. The technique contains two laser beams propagating in a perpendicular configuration. The tunable laser beam along the axis of the ring-down cell probes the Br2 fragment in the B${}^3\Pi _{ou}^ +$Πou+3–X${}^1\Sigma _g^ +$Σg+1 transition. The measurements of laser energy- and pressure-dependence and addition of a Br scavenger are further carried out to rule out the probability of Br2 contribution from a secondary reaction. By means of spectral simulation, the ratio of nascent vibrational population for v = 0, 1, and 2 levels is evaluated to be 1:(0.65 ± 0.09):(0.34 ± 0.07), corresponding to a Boltzmann vibrational temperature of 893 ± 31 K. The quantum yield of the ground state Br2 elimination reaction is determined to be 0.11 ± 0.06. With the aid of ab initio potential energy calculations, the pathway of molecular elimination is proposed on the energetic ground state (COBr)2 via internal conversion. A four-center dissociation mechanism is followed synchronously or sequentially yielding three fragments of Br2 + 2CO. The resulting Br2 is anticipated to be vibrationally hot. The measurement of a positive temperature effect supports the proposed mechanism.
Formation mechanisms of spatially-directed zincblende gallium nitride nanocrystals
Authors: Wood A. W. , Collino R. R. , Cardozo B. L. , Naab F. , Wang Y. Q. , Goldman R. S.
Published: December 2011

We report on the spatially selective formation of GaN nanocrystals embedded in GaAs. Broad-area N+ implantation followed by rapid thermal annealing leads to the formation of nanocrystals at the depth of maximum ion damage. With additional irradiation using a Ga+ focused ion beam, selective lateral positioning of the nanocrystals within the GaAs matrix is observed in isolated regions of increased vacancy concentration. Following rapid thermal annealing, the formation of zincblende GaN is observed in the regions of highest vacancy concentration. The nucleation of zincblende nanocrystals over the wurtzite phase of bulk GaN is consistent with the predictions of a thermodynamic model for the nanoscale size-dependence of GaN nucleation.
Formation of organized nanostructures from unstable bilayers of thin metallic liquids
Authors: Khenner Mikhail , Yadavali Sagar , Kalyanaraman Ramki
Published: December 2011

Dewetting of pulsed-laser irradiated, thin (<20 nm), optically reflective metallic bilayers on an optically transparent substrate with a reflective support layer is studied within the lubrication equations model. A steady-state bilayer film thickness (h) dependent temperature profile is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Large thermocapillary forces are observed along the plane of the liquid-liquid and liquid-gas interfaces due to this h-dependent temperature, which, in turn, is strongly influenced by the h-dependent laser light reflection and absorption. Consequently the dewetting is a result of the competition between thermocapillary and intermolecular forces. A linear analysis of the dewetting length scales established that the non-isothermal calculations better predict the experimental results as compared to the isothermal case within the bounding Hamaker coefficients. Subsequently, a computational non-linear dynamics study of the dewetting pathway was performed for Ag/Co and Co/Ag bilayer systems to predict the morphology evolution. We found that the systems evolve towards formation of different morphologies, including core-shell, embedded, or stacked nanostructure morphologies.
Denaturation of proteins near polar surfaces
Authors: Starzyk Anna , Cieplak Marek
Published: December 2011

All-atom molecular dynamics simulations for proteins placed near a model mica surface indicate existence of two types of evolution. One type leads to the surface-induced unfolding and the other just to a deformation. The two behaviors are characterized by distinct properties of the radius of gyration and of a novel distortion parameter that distinguishes between elongated, globular, and planar shapes. They also differ in the nature of their single site diffusion and two-site distance fluctuations. The four proteins chosen for the studies, the tryptophan cage, protein G, hydrophobin and lyzozyme, are small to allow for a fair determination of the forces generated by the surface as the effects of finite cutoffs in the Coulombic interactions are thus minimized. When the net charge on the surface is set to zero artificially, infliction of deformation is seen to persists but no unfolding takes place. Unfolding may also be prevented by a cluster of disulfide bonds, as we observe in simulations of hydrophobin.
Crystal particle Raman-scattering and applications for improved solar cell performance
Authors: Lee Ping , Shank Jason , Magsi Komal , Kang Yeona , Fortmann C. M.
Published: December 2011

Raman-based spectral modification for improved solar cell (SC) performance was investigated. While, Raman scattering is a weak phenomena commonly used for material characterization, small-sized particles embedded in a light scattering matrix have increased Raman and increased anti-Stokes energy up shift probability; because, embedding particles in a diffusive, transparent matrix vastly increases light path lengths (kilometers) and because optically generated phonons contribute to anti-Stokes probability in long phonon lifetime small particles. Increased long wavelength quantum efficiency was obtained using these layers on silicon SCs. Diffusion theory was applied to the spatial light diffusion and to Raman light energy broadening.
Statistical mechanics and large-scale velocity fluctuations of turbulence
Authors: Mouri Hideaki , Hori Akihiro , Kawashima Yoshihide , Hashimoto Kosuke
Published: December 2011

Turbulence exhibits significant velocity fluctuations even if the scale is much larger than the scale of the energy supply. Since any spatial correlation is negligible, these large-scale fluctuations have many degrees of freedom and are thereby analogous to thermal fluctuations studied in the statistical mechanics. By using this analogy, we describe the large-scale fluctuations of turbulence in a formalism that has the same mathematical structure as used for canonical ensembles in the statistical mechanics. The formalism yields a universal law for the energy distribution of the fluctuations, which is confirmed with experiments of a variety of turbulent flows. Thus, through the large-scale fluctuations, turbulence is related to the statistical mechanics.
State-dependent doubly weighted stochastic simulation algorithm for automatic characterization of stochastic biochemical rare events
Authors: Roh Min K. , Daigle Bernie J. , Gillespie Dan T. , Petzold Linda R.
Published: December 2011

In recent years there has been substantial growth in the development of algorithms for characterizing rare events in stochastic biochemical systems. Two such algorithms, the state-dependent weighted stochastic simulation algorithm (swSSA) and the doubly weighted SSA (dwSSA) are extensions of the weighted SSA (wSSA) by H. Kuwahara and I. Mura [J. Chem. Phys. 129, 165101 (2008)]10.1063/1.2987701. The swSSA substantially reduces estimator variance by implementing system state-dependent importance sampling (IS) parameters, but lacks an automatic parameter identification strategy. In contrast, the dwSSA provides for the automatic determination of state-independent IS parameters, thus it is inefficient for systems whose states vary widely in time. We present a novel modification of the dwSSA—the state-dependent doubly weighted SSA (sdwSSA)—that combines the strengths of the swSSA and the dwSSA without inheriting their weaknesses. The sdwSSA automatically computes state-dependent IS parameters via the multilevel cross-entropy method. We apply the method to three examples: a reversible isomerization process, a yeast polarization model, and a lac operon model. Our results demonstrate that the sdwSSA offers substantial improvements over previous methods in terms of both accuracy and efficiency.
Planar-type In0.53Ga0.47As channel band-to-band tunneling metal-oxide-semiconductor field-effect transistors
Authors: Iida Ryo , Kim Sang-Hyeon , Yokoyama Masafumi , Taoka Noriyuki , Lee Sang-Hoon , Takenaka Mitsuru , Takagi Shinichi
Published: December 2011

We present the operation of planer-type In0.53Ga0.47As- and In0.53Ga0.47As- on-insulator-channel band-to-band-tunneling MOSFETs with Ion/Ioff ratio of ∼105 in the VG swing of 1.5 V and sub-threshold slope (S.S.) of around 230 mV/dec at room temperature. It is experimentally found that the reduction in equivalent oxide thickness (EOT) of the gate insulators and the increase in the steepness of Be profiles in the source region effectively decrease the S.S. values. The experimental S.S. values at low temperature of 4.2 K amount to 110 and 63 mV/dec for tunneling field-effect transistors (TFET) with the gate insulator EOT of 4.5 and 2.9 nm, respectively. The TFET current has exhibited strong temperature dependence attributable to trap-related leakage current, which significantly degrades the S.S. values around room temperature. On the other hand, the results of the 2-dimensional device simulation show that the S.S. values at 4.2 K can be quantitatively represented by band-to-band tunneling current in the present TFETs. It is shown from the analyses using this device simulation that further improvement of the S.S. value in planar InGaAs TFETs can be realized by the reduction in the defect density, the thinning EOT and the improvement in the steepness of the Be profiles in the source p+/n junction of TFETs.