bluuebunny/crossref_metadata_2025 huggingface dataset:
A late Holocene slip rate for the central North Anatolian fault, at Tahtaköprü, Turkey, from cosmogenic 10Be geochronology: Implications for fault loading and strain release rates
Authors: Kozacı Özgür , Dolan James F. , Finkel Robert C.
Published: January 2009

Measurement of a stream offset and cosmogenic dating (10Be) of the alluvial surface into which the stream incised yield a preferred late Holocene slip rate of 18.6 +3.5/−3.3 mm a−1 for the central part of the North Anatolian fault (NAF) at Tahtaköprü, Turkey; use of variable cosmogenic production rate (VPR) models yields a slightly slower rate of ∼16.4 +6.4/−4.5 mm a−1. The offset drainage (Karanlık Dere), which flows southward almost perpendicular to the east‐west trace of the NAF at the site, is displaced right laterally by 55 ± 10 m, with no vertical displacement. A 10Be age of ∼3 ka (∼3.5 ka VPR) from the top of a boulder on the best preserved part of the incised alluvial surface provides the most reliable maximum age for the onset of incision; 11 10Be ages from cobbles collected from the cultivated surface to the south yield younger ages, consistent with exhumation, erosion, and mechanical mixing during plowing. Our 18.6 +3.5/−3.3 mm a−1 rate is similar to other geologic slip rates measured along the NAF, all of which cluster between 15 and 20 mm a−1 over a wide range of (103–105) timescales. All of these geological rates, however, are slower than the ∼25 ± 2 mm a−1 short‐term rate of elastic strain accumulation measured geodetically. This disparity suggests the possibility that the NAF is experiencing a strain transient in which the lower crust beneath the fault is deforming faster than its long‐term rate.
Analyzing the contribution of aerosols to an observed increase in direct normal irradiance in Oregon
Authors: Riihimaki L. D. , Vignola F. E. , Long C. N.
Published: January 2009

Annual average total irradiance increases by 1–2% per decade at three monitoring stations in Oregon over the period from 1980 to 2007. Direct normal irradiance measurements increase by 5% per decade over the same time period. The measurements show no sign of a dimming before 1990. The impact of high concentrations of stratospheric aerosols following the volcanic eruptions of El Chichón and Mount Pinatubo are clearly seen in the measurements. Removing these years from the annual average all‐sky time series reduces the trends in both total and direct normal irradiance. Clear‐sky periods from this long direct normal time series are used in conjunction with radiative transfer calculations to test whether part of the increase could be caused by anthropogenic aerosols. All three sites show relatively low clear‐sky measurements before the eruption of El Chichón in 1982, suggesting higher aerosol loads during this period. After removing the periods most strongly impacted by volcanic eruptions, two of the sites show statistically significant increases in clear‐sky direct normal irradiance from 1987 to 2007. Radiative transfer calculations of the impact of volcanic aerosols and tropospheric water vapor indicate that only about 20% of that clear‐sky increase between background aerosol periods before and after the eruption of Mount Pinatubo can be explained by these two factors. Thus a statistically significant clear‐sky trend remains between 1987 and 2007 that is consistent with the hypothesis that at least some of the increase in surface irradiance could be caused by a reduction of anthropogenic aerosols.
Effects of simplifying fracture network representation on inert chemical migration in fracture‐controlled aquifers
Authors: Wellman Tristan P. , Shapiro Allen M. , Hill Mary C.
Published: January 2009

While it is widely recognized that highly permeable ‘large‐scale' fractures dominate chemical migration in many fractured aquifers, recent studies suggest that the pervasive ‘small‐scale’ fracturing once considered of less significance can be equally important for characterizing the spatial extent and residence time associated with transport processes. A detailed examination of chemical migration through fracture‐controlled aquifers is used to advance this conceptual understanding. The influence of fracture structure is evaluated by quantifying the effects to transport caused by a systematic removal of fractures from three‐dimensional discrete fracture models whose attributes are derived from geologic and hydrologic conditions at multiple field sites. Results indicate that the effects to transport caused by network simplification are sensitive to the fracture network characteristics, degree of network simplification, and plume travel distance, but primarily in an indirect sense since correlation to individual attributes is limited. Transport processes can be ‘enhanced’ or ‘restricted’ from network simplification meaning that the elimination of fractures may increase or decrease mass migration, mean travel time, dispersion, and tailing of the concentration plume. The results demonstrate why, for instance, chemical migration may not follow the classic advection‐dispersion equation where dispersion approximates the effect of the ignored geologic structure as a strictly additive process to the mean flow. The analyses further reveal that the prediction error caused by fracture network simplification is reduced by at least 50% using the median estimate from an ensemble of simplified fracture network models, and that the error from network simplification is at least 70% less than the stochastic variability from multiple realizations.
Record 2007 Greenland Ice Sheet Surface Melt Extent and Runoff
Authors: Mernild Sebastian H. , Liston Glen E. , Hiemstra Christopher A. , Steffen Konrad
Published: January 2009

Record surface melting from the Greenland ice sheet (GrIS) occurred in 2007, according to observations [Mote, 2007; Tedesco, 2007]. The surface melting and freshwater runoff contribution are of considerable importance to, for example, the global eustatic sea level rise and the ocean salinity.

Remote locations and harsh climatic conditions are commonly cited as reasons for the lack of knowledge about the snow and ice contained within Greenland. Modeling studies incorporating available data sets are valuable resources in illuminating GrIS melting and runoff changes. Snow‐Model [Liston and Elder, 2006a, 2006b], a snow evolution modeling system simulating snow‐related physical processes, was used to model the GrIS surface water balance, including spatial variations in snow accumulation and redistribution, snowmelt and ice melt, and water balance components such as runoff (see equation below for further information), on the GrIS for 1995–2007. If snow temperature is below freezing, any percolating or liquid water refreezes and is stored in the snow (in the “pores”) as internal accumulation. This provides a method to account for heat and mass transfer processes, such as snowpack ripening, during spring melt.
Launch of astronomy year 2009
Authors: Showstack Randy
Published: January 2009

The International Year of Astronomy (IYA2009) will involve 135 nations and thousands of events around the world. In addition to opening ceremonies in Paris on 15–16 January and in many other countries during January and February, other planned events include the Cosmic Diary project about the daily lives of full‐time astronomers; the 365 Days of Astronomy project to publish one podcast per day during the entire year; and the 100 Hours of Astronomy project on 2–5 April, which includes the goal of having as many people as possible look through a telescope.
Bower Award call for nominations
Authors: Showstack Randy
Published: January 2009

The Franklin Institute is seeking nominations for the 2010 Bower Award and Prize for Achievement in Science, for the theme of Earth systems. The award, which comes with a gold medal and a US$250,000 cash prize, recognizes individuals “who have made significant scientific contributions to our understanding of the interrelationships among Earth systems leading to increased predictability of natural or human‐induced changes on the planet.”
Managed Relocation of Species: Noah's Ark or Pandora's Box?: Assisted Migration: Evaluating a New Strategy for Species Conservation; Milwaukee, Wisconsin, 1–3 August 2008
Authors: Safford Hugh D. , Hellmann Jessica J. , McLachlan Jason , Sax Dov F. , Schwartz Mark W.
Published: January 2009

The world's human population is growing rapidly. Annually we may now move more earth than natural geological processes, and our dependence on fossil fuels is causing wholesale changes in climate and many ecosystem processes. Although human impacts on the globe have long had major consequences for the Earth's other inhabitants, the current combination of massive habitat change and rapid climate change poses an especially daunting challenge for many species. Rates of anthropogenic global change, from habitat alteration to modifications of the atmosphere, are so high that many species do not possess the capacity to “track” these changes through natural dispersal. In addition, “humanized” landscapes are now so pervasive in some parts of the globe that natural dispersal corridors have all but completely disappeared.
Identifying Crucial Issues in Climate Science: Drastic Change in the Earth System During Global Warming; Sapporo, Japan, 24 June 2008
Authors: Ikeda Motoyoshi , Greve Ralf , Hara Toshika , Watanabe Yutaka W. , Ohmura Atsumu , Ito Akihiko , Kawamiya Michio
Published: January 2009

The Nobel Peace Prize awarded to the Intergovernmental Panel on Climate Change (IPCC) and former U.S. vice president Al Gore indicates that global warming is recognized as a real phenomenon critical to human beings. However, humanity's knowledge concerning global warming is based on an uncertainty larger than 50% in the warming rate during the past century. Therefore, scientific clarification is needed to understand important mechanisms that potentially produce positive feedbacks in the Earth system—such mechanisms must be better understood before scientists can develop more reliable predictions.
Bender Receives 2008 Roger Revelle Medal
Authors: Sarmienton Jorge , Bender Michael L.
Published: January 2009

Michael L. Bender was awarded the 2008 AGU Roger Revelle Medal at the AGU Fall Meeting Honors Ceremony, held 17 December 2008 in San Francisco, Calif. The medal is for “outstanding contributions in atmospheric sciences, atmosphere‐ocean coupling, atmosphere‐land coupling, biogeochemical cycles, climate, or related aspects of the Earth system.”
Correction to [“Meeting Report: Ocean Carbon Cycling and Climate Impacts on Marine Ecosystems”]
Authors: Anonymous
Published: January 2009

In the 18 November 2008 issue (Eos, 89(47), 472), a sentence in the fourth paragraph of the meeting report entitled “Ocean Carbon Cycling and Climate Impacts on Marine Ecosystems” was incorrect.
Fast Isotopic Exchange between Mitochondria and Cytosol in Brain Revealed by Relayed 13C Magnetization Transfer Spectroscopy
Authors: Yang Jehoon , Xu Su , Shen Jun
Published: January 2009

In vivo13C magnetic resonance spectroscopy has been applied to studying brain metabolic processes by measuring 13C label incorporation into cytosolic pools such as glutamate and aspartate. However, the rate of exchange between mitochondrial α-ketoglutarate/oxaloacetate and cytosolic glutamate/aspartate ( Vx) extracted from metabolic modeling has been controversial. Because brain fumarase is exclusively located in the mitochondria, and mitochondrial fumarate is connected to cytosolic aspartate through a chain of fast exchange reactions, it is possible to directly measure Vx from the four-carbon side of the tricarboxylic acid cycle by magnetization transfer. In isoflurane-anesthetized adult rat brain, a relayed 13C magnetization transfer effect on cytosolic aspartate C2 at 53.2ppm was detected after extensive signal averaging with fumarate C2 at 136.1ppm irradiated using selective radiofrequency pulses. Quantitative analysis using Bloch–McConnell equations and a four-site exchange model found that VxE13–19 µmol per g per min (≫ VTCA, the tricarboxylic acid cycle rate) when the longitudinal relaxation time of malate C2 was assumed to be within ±33% of that of aspartate C2. If VxE VTCA, the isotopic exchange between mitochondria and cytosol would be too slow on the time scale of 13C longitudinal relaxation to cause a detectable magnetization transfer effect.
Simulations of nucleation and elongation of amyloid fibrils
Authors: Zhang Jianing , Muthukumar M.
Published: January 2009

We present a coarse-grained model for the growth kinetics of amyloid fibrils from solutions of peptides and address the fundamental mechanism of nucleation and elongation by using a lattice Monte Carlo procedure. We reproduce the three main characteristics of nucleation of amyloid fibrils: (1) existence of lag time, (2) occurrence of a critical concentration, and (3) seeding. We find the nucleation of amyloid fibrils to require a quasi-two-dimensional configuration, where a second layer of β sheet must be formed adjunct to a first layer, which in turn leads to a highly cooperative nucleation barrier. The elongation stage is found to involve the Ostwald ripening (evaporation-condensation) mechanism, whereby bigger fibrils grow at the expense of smaller ones. This new mechanism reconciles the debate as to whether protofibrils are precursors or monomer reservoirs. We have systematically investigated the roles of time, peptide concentration, temperature, and seed size. In general, we find that there are two kinds of lag time arising from two different mechanisms. For higher temperatures or low enough concentrations close to the disassembly boundary, the fibrillization follows the nucleation mechanism. However, for low temperatures, where the nucleation time is sufficiently short, there still exists an apparent lag time due to slow Ostwald ripening mechanism. Consequently, the lag time is nonmonotonic with temperature, with the shortest lag time occurring at intermediate temperatures, which in turn depend on the peptide concentration. While the nucleation dominated regime can be controlled by seeding, the Ostwald ripening regime is insensitive to seeding. Simulation results from our coarse-grained model on the fibril size, lag time, elongation rate, and solubility are consistent with available experimental observations on many specific amyloid systems.
On the importance of vibrational contributions to small-angle optical rotation: Fluoro-oxirane in gas phase and solution
Authors: Pedersen Thomas Bondo , Kongsted Jacob , Crawford T. Daniel , Ruud Kenneth
Published: January 2009

The specific optical rotation of (S)-fluoro-oxirane in gas phase and solution is predicted using time-dependent density functional theory (B3LYP functional) and coupled cluster linear response theory. Upon vibrational averaging, the coupled cluster singles and doubles model predicts the gas phase specific optical rotation to be 8.1° (dm g/cm3)−1 at 355 nm at room temperature. This is an order of magnitude smaller than the B3LYP result of 68.4° (dm g/cm3)−1. The main source of this discrepancy is the electronic contribution at the equilibrium geometry. The effects of cyclohexane and acetonitrile solvents are calculated for both the electronic and vibrational contributions with the B3LYP functional. The specific optical rotation is estimated to change significantly depending on the polarity of the solvent, increasing in cyclohexane and decreasing in acetonitrile.
Evaluating the transferability of coarse-grained, density-dependent implicit solvent models to mixtures and chains
Authors: Allen Erik C. , Rutledge Gregory C.
Published: January 2009

Previously, we described a coarse-graining method for creating local density-dependent implicit solvent (DDIS) potentials that reproduce the radial distribution function (RDF) and solute excess chemical potential across a range of particle concentrations [E. C. Allen and G. C. Rutledge, J. Chem. Phys. 128, 154115 (2008)]. In this work, we test the transferability of these potentials, derived from simulations of monomeric solute in monomeric solvent, to mixtures of solutes and to solute chains in the same monomeric solvent. For this purpose, “transferability” refers to the predictive capability of the potentials without additional optimization. We find that RDF transferability to mixtures is very good, while RDF errors in systems of chains increase linearly with chain length. Excess chemical potential transferability is good for mixtures at low solute concentration, chains, and chains of mixed composition; at higher solute concentrations in mixtures, chemical potential transferability fails due to the nature of the DDIS potentials, in which particle insertion directly affects the interaction potential. With these results, we demonstrate that DDIS potentials derived for pure solutes can be used effectively in the study of many important systems including those involving mixtures, chains, and chains of mixed composition in monomeric solvent.
Molecular dynamics simulation of the contact angle of liquids on solid surfaces
Authors: Shi Bo , Dhir Vijay K.
Published: January 2009

In this work, Lennard-Jones liquid and water droplets are simulated adjacent to a solid surface using molecular dynamics. The contact angle is obtained by using direct simulation. The particle-particle particle-mesh method [B. Shi, S. Sinha, and V. K. Dhir, J. Phys. Chem. 124, 204715 (2006)] for long range force correction is used in the simulation. The contact angle is studied as a function of system temperature and the solid/fluid interaction potential. It is shown that the contact angle decreases with increasing system temperature and increases when the potential decreases. At high system temperature (pressure), the contact angle drops to zero. The predictions are compared with data from experiments and a reasonable agreement is found.
High-accuracy calculations of the ground, 1 A11′, and the 2 A11′, 2 A31′, and 1 E1′ excited states of H3+
Authors: Pavanello Michele , Adamowicz Ludwik
Published: January 2009

Accurate variational Born–Oppenheimer calculations of the 1 A11′, 2 A11′, 2 A31′, and 1 E1′ states of the H3+ ion at the ground-state equilibrium geometry are reported. The wave functions of the states are expanded in terms of explicitly correlated spherical Gaussian functions with shifted centers. In the variational optimization the analytical gradient of the energy with respect to the nonlinear exponential parameters of the Gaussians has been employed. The energies obtained in the calculations are the best variational estimates ever calculated for the four states. One-electron densities for the states, as well as a D3h-restricted potential energy surface of the ground state calculated around the equilibrium geometry, are also presented and discussed.
UV photodissociation of methyl bromide and methyl bromide cation studied by velocity map imaging
Authors: Blanchet Valérie , Samartzis Peter C. , Wodtke Alec M.
Published: January 2009

We employ the velocity map imaging technique to measure kinetic energy and angular distributions of state selected CH3 (v2=0,1,2,3) and Br (P23/2, P21/2) photofragments produced by methyl bromide photolysis at 215.9 nm. These results show unambiguously that the Br and Br∗ forming channels result in different vibrational excitations of the umbrella mode of the methyl fragment. Low energy structured features appear on the images, which arise from CH3Br+ photodissociation near 330 nm. The excess energy of the probe laser photon is channeled into CH3+ vibrational excitation, most probably in the ν4 degenerate bend.
Comment on “Residual multiparticle entropy does not generally change sign near freezing” [J. Chem. Phys. 128, 161101 (2008)]
Authors: Giaquinta Paolo V.
Published: January 2009

Does the vanishing of the residual multiparticle entropy, a quantity defined as the cumulative contribution of more-than-two-particle density correlations to the excess entropy of a fluid, have physical significance? We address this question in the light of the arguments presented in the paper that is being commented on and of the phenomenology thus far explored in a variety of model systems undergoing thermodynamic or structural transformations into more ordered (but not necessarily crystalline) states or regimes.
Diversity-Oriented Synthesis of Substituted Furo[2,3-b]pyrazines
Authors: Mehta Vaibhav P. , Modha Sachin G. , Ermolat'ev Denis , Van Hecke Kristof , Van Meervelt Luc , Van der Eycken Erik V.
Published: January 2009

A highly efficient method for the synthesis of diversely substituted furo[2,3-b]pyrazines has been elaborated. The Ag+- or iodine-mediated electrophilic cyclization of readily generated 5-chloro-3-substituted ethynyl-1-(4-methoxybenzyl)-pyrazin-2(1H)-ones affords substituted furo[2,3-b]pyrazines, which undergo various palladium catalyzed reactions to generate a library of difficult to attain diversely substituted furo[2,3-b]pyrazines.
Simplifying the Free-Radical Polymerization of Styrene: Microwave-Assisted High-Temperature Auto Polymerizations
Authors: Erdmenger Tina , Becer C. Remzi , Hoogenboom Richard , Schubert Ulrich S.
Published: January 2009

We have investigated the combination of the thermally auto-initiated free radical polymerization of styrene and precipitation polymerization in order to develop a fast and environmentally friendly approach to produce polystyrene. To achieve high reaction temperatures in a short period of time, microwave irradiation was utilized as the heating source. Styrene was used without any purification, e.g., without distillation or column filtration. Due to the auto-initiation of styrene at high temperatures no radical initiator was required. Different water- or ethanol-to-styrene ratios were heated far beyond their boiling points and at relatively high pressures for the auto-initiated polymerization of styrene. The obtained molecular weights could be controlled by the ethanol-to-styrene ratio in the case of ethanol as the solvent although the monomer conversions were rather low under the applied conditions. Moreover, the effect of a commercially available stable free nitroxide was investigated on the control over the polymerization. It has been observed that it is possible to control the molecular weight of the polymer by changing the ratio of styrene to free nitroxide (varied from 10:1 to 400:1) and moderate polydispersity indices (PDI = 1.3 to 1.9) could be obtained. Finally, the developed polymerization processes only require a simple purification step due to the precipitation of the polystyrene in the reaction solvent.
The Regio- and Stereo-Selective Formation of Allylic Chlorides During the Overman Rearrangement of Trichloroacetimidates Derived from Certain Brominated Conduritols
Authors: Matveenko Maria , Willis Anthony C. , Banwell Martin G.
Published: January 2009

Microwave irradiation of imidate 2 at 165°C affords a ~3:1 mixture of the Overman rearrangement product 3 and the allylic chloride 4 (83% combined yield). Under the same conditions the deoxy-conduritol 6 gives a comparable mixture of compounds 7 and 8. The single-crystal X-ray structure of a derivative of chloride 8 is reported together with a mechanism that accounts for the selective formation of this compound and congener 4.
Behavioural ecology of red and grey kangaroos: Caughley's insights into individuals, associations and dispersion
Authors: Coulson Graeme
Published: January 2009

In 1964, Graeme Caughley published two papers on the activity, density, dispersion and social organisation of kangaroos. He made direct observations of the behaviour of two species, and used measures of their faecal pellets to infer habitat use. This work paved the way for many studies of the behaviour of individual kangaroos, the associations between them, and the dispersion of individuals within a population. At an individual level, activity budgets of kangaroos are now known to be influenced by extrinsic factors such as weather, season, and forage conditions, as well as intrinsic factors such as sex and reproductive status. Habitat selection is understood in terms of the requirement for both food and horizontal cover, and past predation continues to play a role in the use of cover, as Caughley first proposed. At the level of associations among individuals, group size is positively related to population density, as Caughley predicted, but is also influenced by habitat structure. Contrary to his views, the high rate of group flux does not represent random movement of individuals. Instead, there are subtle yet persistent associations between related individuals. There is also strong dissociation between population classes when sexual segregation occurs during the non-mating period in seasonally breeding populations. Despite these effects, kangaroos are only weakly constrained by social factors, suggesting that population dispersion may conform to ideal free distribution when food resources are limited. At a management level, this suggests that kangaroos have the potential to redistribute rapidly after culling programs aimed at reducing density in overabundant populations.
Transcatheter coil embolization for steal syndrome in patients with hemodialysis access
Authors: Kariya S. , Tanigawa N. , Kojima H. , Komemushi A. , Shomura Y. , Shiraishi T. , Kawanaka T. , Sawada S.
Published: January 2009

Background: Drainage of large amounts of shunt blood into deep veins via collaterals reduces resistance to venous outflow and decreases blood flow to the artery distal to the arterial anastomotic site, potentially resulting in steal syndrome.

Purpose: To evaluate the effectiveness of transcatheter coil embolization for collateral veins of hemodialysis access in the treatment of steal syndrome.

Materials and Methods: Five hemodialysis patients (four male, one female; mean age 58.8 years, range 40–71 years) with symptomatic steal syndrome were treated. Steal syndrome was diagnosed based on decreased or absent distal pulse, coolness, pain, abnormal skin color, ischemic ulceration of digits, numbness, sensory impairment, or motor impairment. Coil embolization was performed to block collaterals communicating with deep veins, with conscious sedation and local anesthesia. Fistulography was performed before, immediately after, and 1 month after embolization. Ultrasonography was performed 2 days after embolization. Symptoms and signs were assessed 2 days after embolization. Clinical findings related to steal syndrome and access failure were observed at each hemodialysis.

Results: Blood flow in the collaterals was successfully blocked by coil embolization in all patients. Distal pulse, coolness, pain, and skin color improved in all patients. Numbness, sensory impairment, and motor impairment were unimproved in two patients. In all patients, hemodialysis following embolization was performed normally. The mean observation period after embolization was 33 months (range 9–75 months).

Conclusion: Coil embolization of collaterals that drain shunt blood into deep veins is effective for steal syndrome for hemodialysis access originating in the brachial artery.
Rat model of reperfused partial liver infarction: Characterization with multiparametric magnetic resonance imaging, microangiography, and histomorphology
Authors: Wu X. , Wang H. , Chen F. , Jin L. , Li J. , Feng Y. , DeKeyzer F. , Yu J. , Marchal G. , Ni Y.
Published: January 2009

Background: Rat model of reperfused partial liver infarction (RPLI) has been increasingly used in studying new diagnostics and therapeutics.

Purpose: To characterize the RPLI model using magnetic resonance imaging (MRI), microangiography, and histopathology.

Material and Methods: RPLI was induced in eight rats by occluding hepatic inflow to the right liver lobe for 3 hours. MRI was performed at a 1.5T clinical scanner 6 hours after reperfusion to obtain T2-weighted (T2WI), T1-weighted (T1WI), contrast-enhanced (CE) T1WI, diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) maps, T1-weighted dynamic contrast-enhanced (T1-DC) perfusion-weighted imaging (PWI), and T2*-weighted dynamic susceptibility contrast-enhanced (T2*-DSC) PWI images. Rats were sacrificed for microangiography and histomorphology. In vivo morphological and functional MRI parameters, including maximum initial slope (MIS), K value, relative blood flow (rBF), relative blood volume (rBV), time to peak (TTP), and mean transit time (MTT), were matched with postmortem findings.

Results: The infarcted lobe was conspicuous from normal liver with lower and higher signal intensity on T1WI ( P=0.018) and T2WI ( P=0.001), respectively. Contrast between infarcted and normal liver reversed on CE-T1WI after gadolinium injection. The infarction averaged 37.5% of total liver volume. DWI and ADC maps were able to detect subtle perfusion-related differences ( P<0.05). With T1-DC-PWI, increased extravasation and vascular permeability were reflected by significantly greater MIS ( P=0.034) and K value ( P=0.014) in infarction. T2*-DSC-PWI showed lower rBF and rBV with shorter TTP and MTT in infarcted liver ( P<0.05). In vivo MRI findings corresponded well with postmortem outcomes.

Conclusion: RPLI in rats could be characterized by multiparametric MRI and postmortem assessments, with insight into the no-reflow phenomenon, which implies its further application for preclinical assessments of new pharmaceutics.
ANALYZING INTER-ORGANIZATIONAL RELATIONSHIPS IN THE CONTEXT OF THEIR NATIONAL BUSINESS SYSTEMS
Authors: Bachmann Reinhard , van Witteloostuijn Arjen
Published: January 2009

This paper suggests a cross-country comparative framework for the study of inter-organizational relationships. It provides a perspective that links the micro-, meso- and macro-levels of analysis, dealing with the following issues: (a) the role of socio-organizational factors in relationships across organizational boundaries; (b) legal contractual arrangements, human capital features, and the practices of using information and communication technologies as key factors in the environment in which inter-organizational relationships are embedded; and (c) convergence versus divergence of cultural and institutional patterns of national business systems. Also, the effects of governance regime (Anglo-Saxon vis-à-vis Continental-European) and population size (large vis-à-vis small) are argued to play an important role in determining the quality of inter-organizational relationships across Western European national business systems. The conceptual argument presented in this article is illustrated by reference to Germany, the UK, The Netherlands and Ireland.
LIFE STAGES AND TRANSFORMATIONS OF THE LABOR MARKET
Authors: Plessz Marie
Published: January 2009

Various mechanisms, including lower productivity, discrimination and composition effects, have been cited to explain the disadvantaged position on the labor market of young people, women, and persons nearing the end of their working life. This article relies on two hypotheses. First we adopt the perspective of life cycle theory, therefore this phenomenon is also understood as a consequence of giving priority on the job market to fathers between 35 and 40 years old. Second we consider that having a job and the level of earnings are two different dimensions of the labor market and of the way people can be advantaged or disadvantaged. In the case of the Czech Republic, Poland and Hungary in the period running from the 1980s to the early 2000s, the arrangements made vary in time and by country, as is shown by employment chances and earnings for a variety of groups, corresponding here to the life stages of youth, motherhood or fatherhood, and old age. This information brings to light which groups are disadvantaged and in what way. The configurations observed change with the countries’ economic and socio-political transformations, becoming more diverse by country at the end of the period. Older workers appear excluded from the labor market in Hungary; young people in Poland are integrated but paid relatively low wages; in the Czech Republic, where employment rates are relatively high, mothers are less likely to work.
MORE COSMOPOLITAN, NO LESS LOCAL
Authors: Gustafson Per
Published: January 2009

International business travellers are sometimes described as a cosmopolitan elite, with a strong international orientation but a low preference for local involvement and local obligations. This article uses Swedish survey data to investigate these claims, by comparing the orientations of persons who frequently travel abroad at work with the orientations of other workers. Frequent international travellers generally have more cosmopolitan orientations than others, but the local ties are not significantly weaker among frequent travellers than among occasional travellers or non-travellers. In some respects, notably social networks and associational activities, international travellers tend in fact to be more involved than non-travellers in all the four examined spheres – locally, regionally, nationally and internationally. Concerns among social theorists that highly mobile, locally disconnected elites are undermining social cohesion may therefore be exaggerated. Theoretically, the study suggests that localism and cosmopolitanism should not be treated as necessarily opposite and mutually exclusive phenomena, but that mobility in various forms may be used to combine local and cosmopolitan resources.
COSMOPOLITAN EUROPE
Authors: Pichler Florian
Published: January 2009

Cosmopolitanism represents a way of dealing with difference and similarity within changing societies in a globalized world. Amongst other things, cosmopolitan theory claims that the cosmopolitan feels part of a community transcending the borders of national societies and actively embraces diversity among people. Yet, we know little about what cosmopolitans are like and what distinguishes them from non-cosmopolitans on empirical grounds. Using data from the Eurobarometer 57.2 (European Commission 2002), I explore the link between cosmopolitanism and a subjective meaning of ‘being European’, i.e., whether cosmopolitans express different European identities compared to non-cosmopolitans. Results of statistical analysis show that many people feel close to fellow Europeans and thereby express one kind of cosmopolitanism; however, it remains difficult to say who these people are as socio-demographic variables play a negligible role. With respect to the meaning of ‘being European’ it is striking that cosmopolitans have not only developed a stronger but also a more open European identity. This confirms central normative claims of cosmopolitan theory and demonstrates further possibilities to strengthen cosmopolitanization across Europe.
EFFECTS OF DIVORCE ON CHILDREN'S EDUCATIONAL ATTAINMENT IN A MEDITERRANEAN AND CATHOLIC SOCIETY
Authors: Albertini Marco , Dronkers Jaap
Published: January 2009

Previous research has found parental divorce to have negative effects on children's educational attainment; in addition, it has been noted that the effects of divorce are not the same in all western societies. However, research on Catholic and southern European countries is missing. The aim of this paper is to add to the research on the relation between parental divorce and the educational attainment of children in catholic and southern European societies. Italian society differs from other western societies with respect to many characteristics of its family structure, its cultural and religious systems, its social welfare system, and also with respect to the legislation, frequency and characteristics of divorce. Based on data of the Bank of Italy Survey of Households’ Income and Wealth, we find that the educational level of the children with divorced parents is lower than the educational level of children with married parents. The analysis indicates that the education of children born to the least educated divorced mothers lags significantly behind children of the least educated married mothers, while the educational level of children of highly educated mothers does not deviate from that of children of highly educated mothers who remain married. Next, contrary to what has been found in other European societies, this research shows that widowhood has a significant negative effect on children's educational attainment as well. Finally, the study also demonstrates that the negative effect of divorce cannot be explained by the negative impact of the religious climate of the region of residence.
Compact factorization of differentiable mappings
Authors: Cilia Raffaella , Gutiérrez Joaquín , Saluzzo Giuseppe
Published: January 2009

Results on factorization (through linear operators) of polynomials and holomorphic mappings between Banach spaces have been obtained in recent years by several authors. In the present paper, we obtain a factorization result for differentiable mappings through compact operators. Namely, we prove that a mapping

f
:
X
→
Y

f:X\to Y

between real Banach spaces is differentiable and its derivative

f
′

f’

is a compact mapping with values in the space

K

(
X
,
Y
)

{\mathcal K}(X,Y)

of compact operators from

X
X

into

Y
Y

if and only if

f
f

may be written in the form

f
=
g
∘
S

f=g\circ S

, where the intermediate space is normed,

S
S

is a precompact operator, and

g
g

is a Gâteaux differentiable mapping with some additional properties. We also show that if

f
′

f’

is uniformly continuous on bounded sets and takes values in

K

(
X
,
Y
)

{\mathcal K}(X,Y)

, then

f
′

f’

is compact if and only if

f
f

is weakly uniformly continuous on bounded sets.
Essentialities in additive bases
Authors: Hegarty Peter
Published: January 2009

Let

A
A

be an asymptotic basis for

N

0

\mathbb {N}_0

of some order. By an essentiality of

A
A

one means a subset

P
P

such that

A
∖
P

A \backslash P

is no longer an asymptotic basis of any order and such that

P
P

is minimal among all subsets of

A
A

with this property. A finite essentiality of

A
A

is called an essential subset. In a recent paper, Deschamps and Farhi asked the following two questions: (i) Does every asymptotic basis of

N

0

\mathbb {N}_0

possess some essentiality? (ii) Is the number of essential subsets of size at most

k
k

of an asymptotic basis of order

h
h

(a number they showed to be always finite) bounded by a function of

k
k

and

h
h

only? We answer the latter question in the affirmative and answer the former in the negative by means of an explicit construction, for every integer

h
≥
2

h \geq 2

, of an asymptotic basis of order

h
h

with no essentialities.
The Gauss-Bonnet formula of polytopal manifolds and the characterization of embedded graphs with nonnegative curvature
Authors: Chen Beifang
Published: January 2009

Let

M
M

be a connected

d
d

-manifold without boundary obtained from a (possibly infinite) collection

P

\mathcal P

of polytopes of

R

d

{\mathbb R}^d

by identifying them along isometric facets. Let

V
(
M
)

V(M)

be the set of vertices of

M
M

. For each

v
∈
V
(
M
)

v\in V(M)

, define the discrete Gaussian curvature

κ
M

(
v
)

\kappa _M(v)

as the normal angle-sum with sign, extended over all polytopes having

v
v

as a vertex. Our main result is as follows: If the absolute total curvature

∑

v
∈
V
(
M
)

|

κ
M

(
v
)

|

\sum _{v\in V(M)}|\kappa _M(v)|

is finite, then the limiting curvature

κ
M

(
p
)

\kappa _M(p)

for every end

p
∈
End
⁡
M

p\in \operatorname {End} M

can be well-defined and the Gauss-Bonnet formula holds:
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="sigma-summation Underscript v element-of upper V left-parenthesis upper M right-parenthesis union upper E n d upper M Endscripts kappa Subscript upper M Baseline left-parenthesis v right-parenthesis equals chi left-parenthesis upper M right-parenthesis period">

∑

v
∈
V
(
M
)
∪
End
⁡
M

κ
M

(
v
)
=
χ
(
M
)
.

\sum _{v\in V(M)\cup \operatorname {End} M}\kappa _M(v)=\chi (M).

\]
In particular, if

G
G

is a (possibly infinite) graph embedded in a

2
2

-manifold

M
M

without boundary such that every face has at least

3
3

sides, and if the combinatorial curvature

Φ
G

(
v
)
≥
0

\Phi _G(v)\geq 0

for all

v
∈
V
(
G
)

v\in V(G)

, then the number of vertices with nonvanishing curvature is finite. Furthermore, if

G
G

is finite, then

M
M

has four choices: sphere, torus, projective plane, and Klein bottle. If

G
G

is infinite, then

M
M

has three choices: cylinder without boundary, plane, and projective plane minus one point.
Maps preserving the geometric mean of positive operators
Authors: Molnár Lajos
Published: January 2009

Let

H
H

be a complex Hilbert space. The symbol

A
#
B

A\# B

stands for the geometric mean of the positive bounded linear operators

A
,
B

A,B

on

H
H

in the sense of Ando. In this paper we describe the general form of all automorphisms of the set of positive operators with respect to the operation

#
\#

. We prove that if

dim
⁡
H
≥
2

\dim H\geq 2

, any such transformation is implemented by an invertible bounded linear or conjugate-linear operator on

H
H

.
Threefolds containing Bordiga surfaces as ample divisors
Authors: Maeda Hidetoshi
Published: January 2009

Let

L
L

be an ample line bundle on a smooth complex projective variety

X
X

of dimension three such that there exists a smooth member

Z
Z

of

|
L
|

\vert L\vert

. When the restriction

L

Z

L_{Z}

of

L
L

to

Z
Z

is very ample and

(
Z
,

L

Z

)

(Z,L_{Z})

is a Bordiga surface, it is proved that there exists an ample vector bundle

E

\mathcal {E}

of rank two on

P

2

\mathbb {P}^{2}

with

c

1

(

E

)
=
4

c_{1}(\mathcal {E}) = 4

and

3
≤

c

2

(

E

)
≤
10

3 \leq c_{2}(\mathcal {E}) \leq 10

such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="left-parenthesis upper X comma upper L right-parenthesis equals left-parenthesis double-struck upper P Subscript double-struck upper P squared Baseline left-parenthesis script upper E right-parenthesis comma upper H left-parenthesis script upper E right-parenthesis right-parenthesis">

(
X
,
L
)
=
(

P

P

2

(

E

)
,
H
(

E

)
)

(X,L) = (\mathbb {P}_{\mathbb {P}^{2}}(\mathcal {E}),H(\mathcal {E}))

, where

H
(

E

)

H(\mathcal {E})

is the tautological line bundle on the projective space bundle

P

P

2

(

E

)

\mathbb {P}_{\mathbb {P}^{2}}(\mathcal {E})

associated to

E

\mathcal {E}

.
Restriction and extension of Fourier multipliers between weighted 𝐿^{𝑝} spaces on ℝⁿ and 𝕋ⁿ
Authors: Andersen Kenneth , Mohanty Parasar
Published: January 2009

Weighted analogues of de Leeuw’s restriction theorem for Fourier multipliers on

L
p

(

R

n

)

L^p(\mathbb {R}^n)

are obtained. Weighted analogues of related extension theorems for multipliers on

L
p

(

T

)

L^p(\mathbb {T})

are also considered.
Palindromic random trigonometric polynomials
Authors: Conrey J. , Farmer David , Imamoglu Özlem
Published: January 2009

We show that if a real trigonometric polynomial has few real roots, then the trigonometric polynomial obtained by writing the coefficients in reverse order must have many real roots. This is used to show that a class of random trigonometric polynomials has, on average, many real roots. In the case that the coefficients of a real trigonometric polynomial are independently and identically distributed, but with no other assumptions on the distribution, the expected fraction of real zeros is at least one-half. This result is best possible.
On the connectedness of Deligne-Lusztig varieties
Authors: Görtz Ulrich
Published: January 2009

We give a criterion which determines when a union of one-dimensional Deligne-Lusztig varieties has a connected closure. We obtain a new, short proof of the connectedness criterion for Deligne-Lusztig varieties due to Lusztig.
RNA Interference Screen Identifies Usp18 as a Regulator of Epidermal Growth Factor Receptor Synthesis
Authors: Duex Jason E. , Sorkin Alexander
Published: January 2009

Elevated expression of epidermal growth factor receptor (EGFR) contributes to the progression of many types of cancer. Therefore, we developed a high-throughput screen to identify proteins that regulate the levels of EGFR in squamous cell carcinoma. Knocking down various ubiquitination-related genes with small interfering RNAs led to the identification of several novel genes involved in this process. One of these genes, Usp18, is a member of the ubiquitin-specific protease family. We found that knockdown of Usp18 in several cell lines reduced expression levels of EGFR by 50–80%, whereas the levels of other receptor tyrosine kinases remained unchanged. Overexpression of Usp18 elevated EGFR levels in a manner requiring the catalytic cysteine of Usp18. Analysis of metabolically radiolabeled cells showed that the rate of EGFR protein synthesis was reduced up to fourfold in the absence of Usp18. Interestingly, this dramatic reduction occurred despite no change in the levels of EGFR mRNA. This suggests that depletion of Usp18 inhibited EGFR mRNA translation. In fact, this inhibition required the presence of native 5′ and 3′ untranslated region sequences on EGFR mRNA. Together, our data provide evidence for the novel mechanism of EGFR regulation at the translational step of receptor synthesis.
MCAK and Paclitaxel Have Differential Effects on Spindle Microtubule Organization and Dynamics
Authors: Rizk Rania S. , Bohannon Kevin P. , Wetzel Laura A. , Powers James , Shaw Sidney L. , Walczak Claire E.
Published: January 2009

Within the mitotic spindle, there are multiple populations of microtubules with different turnover dynamics, but how these different dynamics are maintained is not fully understood. MCAK is a member of the kinesin-13 family of microtubule-destabilizing enzymes that is required for proper establishment and maintenance of the spindle. Using quantitative immunofluorescence and fluorescence recovery after photobleaching, we compared the differences in spindle organization caused by global suppression of microtubule dynamics, by treating cells with low levels of paclitaxel, versus specific perturbation of spindle microtubule subsets by MCAK inhibition. Paclitaxel treatment caused a disruption in spindle microtubule organization marked by a significant increase in microtubules near the poles and a reduction in K-fiber fluorescence intensity. This was correlated with a faster t1/2 of both spindle and K-fiber microtubules. In contrast, MCAK inhibition caused a dramatic reorganization of spindle microtubules with a significant increase in astral microtubules and reduction in K-fiber fluorescence intensity, which correlated with a slower t1/2 of K-fibers but no change in the t1/2 of spindle microtubules. Our data support the model that MCAK perturbs spindle organization by acting preferentially on a subset of microtubules, and they support the overall hypothesis that microtubule dynamics is differentially regulated in the spindle.