bluuebunny/crossref_metadata_2025 huggingface dataset:
Peter Mair
Authors: Keman Prof. Hans
Published: October 2011

Dr. Peter Mair, Professor of Comparative Politics and Government at the EUI (Florence) has suddenly and unexpectedly passed away, 15 August 2011, at the age of 60. He leaves behind his wife and 3 children. The political science community in Europe and beyond grieves this loss of an outstanding academic, journal editor and teacher. Peter Mair, born 3 March 1951, was a native of Ireland, a graduate of University College Dublin and enjoyed a distinguished academic career and was the author of a large number of books, chapters and articles on comparative and European politics and on party democracy in particular. It is a sad loss to European political science. He graduated in 1974 and began his career as an assistant professor at the University of Limerick. He subsequently lectured at the universities of Strathclyde and Manchester before moving to the European University Institute of Florence in 1979. He moved to the University of Leiden in the Netherlands in 1987 and was appointed professor of comparative politics in 1992. In 2005 he returned to Florence and was appointed head of the department of political and social sciences in 2007. Prof Mair specialised in the study of party and party systems and has written a number of books on the subject. He was co-author of Representative Government in Modern Europe, the fifth edition of which was published this year. He was also co-author of Identity, Competition and Electoral Availability, which was awarded the prestigious Stein Rokkan prize. Peter Mair served the comparative political science community by editorships of the internationally reputed European Journal of Political Science and of West European Politics. Peter was a person of great charm, a congenial colleague and always encouraging students. We grieve over his loss and sympathize with his family he left behind too early and too soon.
ITCZ controls on Late Cretaceous black shale sedimentation in the tropical Atlantic Ocean
Authors: Hofmann P. , Wagner T.
Published: October 2011

This study presents high resolution organic and inorganic proxy records for Coniacian to Santonian black shale on the Demerara Rise (ODP Site 1261) in the western tropical Atlantic off South America. We integrate these records with approximately time equivalent geochemical data from the eastern tropical Atlantic off tropical Africa (ODP Site 959) to extract the underlying relationships of Intertropical Convergence Zone (ITCZ) dynamics and black shale formation in the tropical Cretaceous Atlantic at orbital time scales. The geochemical records from the Demerara Rise show repetitive fluctuations in productivity, ocean redox conditions, and clastic sediment supply consistent with a dynamic paleo‐upwelling regime off tropical South America. Upwelling intensity most likely was driven by shifts of the mean annual position of the ITCZ, which connects the large‐scale precipitation and wind field patterns of the Hadley cells. Upwelling was strongest off South America and burial of oil‐prone organic matter most pronounced when the ITCZ was in its southernmost position, which maximized the impact of NE trade winds on the inner, tropical part of the northern Hadley cell. Geochemical records from the Deep Ivorian Basin (equatorial Atlantic) suggest that source rock formation occurred in phase with regions north of the equator. Off tropical Africa, however, black shale formation was primarily driven by regional rainfall and nutrient export. The results of this study provide a conceptual framework that explains the formation, distribution and quality of petroleum source rocks below the tropical component of the Hadley cells on orbital time scales.
Independent effects of temperature and precipitation on modeled runoff in the conterminous United States
Authors: McCabe Gregory J. , Wolock David M.
Published: October 2011

A water‐balance model is used to simulate time series of water‐year runoff for 4 km × 4 km grid cells for the conterminous United States during the 1900–2008 period. Model outputs are used to examine the separate effects of precipitation and temperature on runoff variability. Overall, water‐year runoff has increased in the conterminous United States and precipitation has accounted for almost all of the variability in water‐year runoff during the past century. In contrast, temperature effects on runoff have been small for most locations in the United States even during periods when temperatures for most of the United States increased significantly.
Hierarchical controls on runoff generation: Topographically driven hydrologic connectivity, geology, and vegetation
Authors: Jencso Kelsey G. , McGlynn Brian L.
Published: October 2011

Understanding the relative influence of catchment structure (topography and topology), underlying geology, and vegetation on runoff response is key to interpreting catchment hydrology. Hillslope‐riparian‐stream (HRS) water table connectivity serves as the hydrologic linkage between a catchment's uplands and the channel network and facilitates the transmission of water and solutes to streams. While there has been tremendous interest in the concept of hydrological connectivity to characterize catchments, few studies have quantified hydrologic connectivity at the stream network and catchment scales with observational data. Here we examine how catchment topography, vegetation, and geology influenced patterns of stream network HRS connectivity and runoff dynamics across 11 nested headwater catchments in the Tenderfoot Creek Experimental Forest (TCEF), MT. This study builds on the empirical findings ofJencso et al.(2009) who found a strong linear relationship (r2= 0.91) between the upslope accumulated area (UAA) and the annual duration of shallow groundwater table connectivity observed across 24 HRS transects (146 groundwater recording wells). We applied this relationship to the entire stream network across 11 nested catchments to quantify the frequency distribution of stream network connectivity through time, and quantify its relationship to catchment‐scale runoff dynamics. Each catchment's hydrologic connectivity duration curve (CDC) was highly related to its flow duration curve (FDC) and the slope of the relationship varied across catchments. The slope represents the streamflow yield per unit connectivity (Conyield). We analyzed the slope of each catchment's CDC‐FDC relationship or Conyield(annual, peak, transition, and base flow periods) in multiple linear regression models with common terrain, land cover vegetation, and geology explanatory variables. Significant predictors (p< 0.05) across 11 catchments included the ratio of flow path distances and gradients to the creek (DFC/GTC), geology, and a vegetation index. The order and strength of these predictors changed seasonally and highlight the hierarchical controls on headwater catchment runoff generation. Our results highlight direct and quantifiable linkages between catchment topography, vegetation, geology, their topology, and hydrologic dynamics.
Social Support for Healthy Behaviors: Scale Psychometrics and Prediction of Weight Loss Among Women in a Behavioral Program
Authors: Kiernan Michaela , Moore Susan D. , Schoffman Danielle E. , Lee Katherine , King Abby C. , Taylor C. Barr , Kiernan Nancy E. , Perri Michael G.
Published: October 2011

Social support could be a powerful weight‐loss treatment moderator or mediator but is rarely assessed. We assessed the psychometric properties, initial levels, and predictive validity of a measure of perceived social support and sabotage from friends and family for healthy eating and physical activity (eight subscales). Overweight/obese women randomized to one of two 6‐month, group‐based behavioral weight‐loss programs (N = 267; mean BMI 32.1 ± 3.5; 66.3% White) completed subscales at baseline, and weight loss was assessed at 6 months. Internal consistency, discriminant validity, and content validity were excellent for support subscales and adequate for sabotage subscales; qualitative responses revealed novel deliberate instances not reflected in current sabotage items. Most women (>75%) “never” or “rarely” experienced support from friends or family. Using nonparametric classification methods, we identified two subscales—support from friends for healthy eating and support from family for physical activity—that predicted three clinically meaningful subgroups who ranged in likelihood of losing ≥5% of initial weight at 6 months. Women who “never” experienced family support were least likely to lose weight (45.7% lost weight) whereas women who experienced both frequent friend and family support were more likely to lose weight (71.6% lost weight). Paradoxically, women who “never” experienced friend support were most likely to lose weight (80.0% lost weight), perhaps because the group‐based programs provided support lacking from friendships. Psychometrics for support subscales were excellent; initial support was rare; and the differential roles of friend vs. family support could inform future targeted weight‐loss interventions to subgroups at risk.
Reduced Physical Activity in Adults at Risk for Type 2 Diabetes Who Curtail Their Sleep
Authors: Booth John N. , Bromley Lindsay E. , Darukhanavala Amy P. , Whitmore Harry R. , Imperial Jacqueline G. , Penev Pamen D.
Published: October 2011

Adults with parental history of type 2 diabetes have high metabolic morbidity, which is exacerbated by physical inactivity. Self‐reported sleep <6 h/day is associated with increased incidence of obesity and diabetes, which may be mediated in part by sleep‐loss‐related reduction in physical activity. We examined the relationship between habitual sleep curtailment and physical activity in adults with parental history of type 2 diabetes. Forty‐eight young urban adults with parental history of type 2 diabetes (27 F/21 M; mean (s.d.) age 26 (4) years; BMI 23.8 (2.5) kg/m2) each completed 13 (2) days of sleep and physical activity monitoring by wrist actigraphy and waist accelerometry while following their usual lifestyle at home. Laboratory polysomnography was used to screen for sleep disorders. The primary outcome of the study was the comparison of total daily activity counts between participants with habitual sleep <6 vs. ≥6 h/night. Secondary measures included daily time spent sedentary and in light, moderate, and vigorous physical activity. Short sleepers had no sleep abnormalities and showed signs of increased sleep pressure consistent with a behavioral pattern of habitual sleep curtailment. Compared to participants who slept ≥6 h/night, short sleepers had 27% fewer daily activity counts (P = 0.042), spent less time in moderate‐plus‐vigorous physical activity (−43 min/day; P = 0.010), and remained more sedentary (+69 min/day; P = 0.026). Our results indicate that young urban adults with parental history of type 2 diabetes who habitually curtail their sleep have less daily physical activity and more sedentary living, which may enhance their metabolic risk.
Wnt3a is involved in the early stage of miPSC and mESC haemopoietic differentiation
Authors: Zhang Wencheng , Yao Hailei , Wang Sihan , Shi Shuangshuang , Lv Yang , He Lijuan , Nan Xue , Yue Wen , Li Yanhua , Pei Xuetao
Published: October 2011

The Wnt/β‐catenin signalling pathway is important in regulating not only self‐renewal of haemopoietic progenitors and stem cells but also haemopoietic differentiation of ESCs (embryonic stem cells). However, it is still not clear how it affects haemopoietic differentiation. We have used a co‐culture system for haemopoietic differentiation of mouse ESCs and iPSCs (induced pluripotent stem cells) in which the Wnt3a gene‐modified OP9 cell line is used as stromal cells. The number of both Flk1+ and CD41+ cells generated from both co‐cultured mouse ESCs and mouse iPSCs increased significantly, which suggest that Wnt3a is involved in the early stages of haemopoietic differentiation of mouse ESCs and mouse iPSCs in vitro.
Identification of graphene crystallographic orientation by atomic force microscopy
Authors: Almeida C. M. , Carozo V. , Prioli R. , Achete C. A.
Published: October 2011

The direct determination of the crystallographic orientation of graphene sheets was performed using lattice resolution atomic force microscopy images. A graphene sample, micromechanically exfoliated onto a SiO2 substrate showing well defined crystal edges, was imaged in lateral force mode. The lateral force images reveal the periodicity of the graphene hexagonal structure allowing the visualization of the lattice symmetries and determination of the crystal orientation. Crystal edges predominantly formed by zigzag or armchair directions were identified. The nature of the edges was confirmed by Raman spectroscopy.
Effect of interface states on the instability under temperature stress in amorphous SiInZnO thin film transistor
Authors: Hyung Kim Do , Kwang Jung Hyun , Hwan Kim Dae , Yeol Lee Sang
Published: October 2011

The instability of amorphous SiInZnO thin-film transistor with different active layer thickness under temperature stress has been investigated using the density of states extracted directly from capacitance-voltage characteristics. Interestingly, it is found that the instability under temperature stress is inversely proportional to the magnitude of interfacial trap density not the total trap density. This was observed from the decrease of the falling rate of activation energy as increasing interfacial trap density. Therefore, the interfacial trap plays a very important role as a key origin for the negative threshold voltage shift under temperature stress in SiInZnO thin-film transistors.
Slippage toughness measurement of soft interface between stiff thin films and elastomeric substrate
Authors: Huang Yin , Feng Xue , Qu Binrui
Published: October 2011

Traditional interfacial toughness measurements for thin films on substrate are not appropriate to the structure composed of stiff films and soft substrate. This paper describes a new bending test system to measure the interfacial toughness for the soft interface between stiff films and elastomeric substrate. The experimental setup including the loading stages is easy to operate and scanning electron microscope is used to in situ monitor the interfacial slippage during loading. The proposed bending test is conducted for silicon film on poly(dimethylsiloxane) substrate. This method demonstrates the promising way to measure the slippage toughness of soft interface involving the flexible electronics and the bio-related fields.
Phase diagram for magnetic reconnection in heliophysical, astrophysical, and laboratory plasmas
Authors: Ji Hantao , Daughton William
Published: October 2011

Recent progress in understanding the physics of magnetic reconnection is conveniently summarized in terms of a phase diagram which organizes the essential dynamics for a wide variety of applications in heliophysics, laboratory, and astrophysics. The two key dimensionless parameters are the Lundquist number and the macrosopic system size in units of the ion sound gyroradius. In addition to the conventional single X-line collisional and collisionless phases, multiple X-line reconnection phases arise due to the presence of the plasmoid instability either in collisional and collisionless current sheets. In particular, there exists a unique phase termed “multiple X-line hybrid phase” where a hierarchy of collisional islands or plasmoids is terminated by a collisionless current sheet, resulting in a rapid coupling between the macroscopic and kinetic scales and a mixture of collisional and collisionless dynamics. The new phases involving multiple X-lines and collisionless physics may be important for the emerging applications of magnetic reconnection to accelerate charged particles beyond their thermal speeds. A large number of heliophysical and astrophysical plasmas are surveyed and grouped in the phase diagram: Earth’s magnetosphere, solar plasmas (chromosphere, corona, wind, and tachocline), galactic plasmas (molecular clouds, interstellar media, accretion disks and their coronae, Crab nebula, Sgr A*, gamma ray bursts, and magnetars), and extragalactic plasmas (active galactic nuclei disks and their coronae, galaxy clusters, radio lobes, and extragalactic jets). Significance of laboratory experiments, including a next generation reconnection experiment, is also discussed.
Application of an impedance matching transformer to a plasma focus
Authors: Bures B. L. , James C. , Krishnan M. , Adler R.
Published: October 2011

A plasma focus was constructed using an impedance matching transformer to improve power transfer between the pulse power and the dynamic plasma load. The system relied on two switches and twelve transformer cores to produce a 100 kA pulse in short circuit on the secondary at 27 kV on the primary with 110 J stored. With the two transformer systems in parallel, the Thevenin equivalent circuit parameters on the secondary side of the driver are: C = 10.9 μF, V0 = 4.5 kV, L = 17 nH, and R = 5 mΩ. An equivalent direct drive circuit would require a large number of switches in parallel, to achieve the same Thevenin equivalent. The benefits of this approach are replacement of consumable switches with non-consumable transformer cores, reduction of the driver inductance and resistance as viewed by the dynamic load, and reduction of the stored energy to produce a given peak current. The system is designed to operate at 100 Hz, so minimizing the stored energy results in less load on the thermal management system. When operated at 1 Hz, the neutron yield from the transformer matched plasma focus was similar to the neutron yield from a conventional (directly driven) plasma focus at the same peak current.
The splitted laser beam filamentation in interaction of laser and an exponential decay inhomogeneous underdense plasma
Authors: Xia Xiongping , Xu Bin , Lu Jianduo , Yi Lin
Published: October 2011

The splitted beam filamentation in interaction of laser and an exponential decay inhomogeneous underdense plasma is investigated. Based on Wentzel-Kramers-Brillouin (WKB) approximation and paraxial/nonparaxial ray theory, simulation results show that the steady beam width and single beam filamentation along the propagation distance in paraxial case is due to the influence of ponderomotive nonlinearity. In nonparaxial case, the influence of the off-axial of α00 and α02 (the departure of the beam from the Gaussian nature) and S02 (the departure from the spherical nature) results in more complicated ponderomotive nonlinearity and changing of the channel density and refractive index, which led to the formation of two/three splitted beam filamentation and the self-distortion of beam width. In addition, influence of several parameters on two/three splitted beam filamentation is discussed.
Field dependent electrical conduction in HfO2/SiO2 gate stack for before and after constant voltage stressing
Authors: Sahoo S. K. , Misra D.
Published: October 2011

The electrical conduction mechanisms contributing to the leakage current at different field regions and different temperatures have been studied in this work. The current-voltage (I-V) measurement of TiN/HfO2/SiO2/P-Si nMOS capacitor in the temperature range from 25 °C to 125 °C, taken before stressing and in the temperature range of 25 °C to 65 °C after constant voltage stressing (CVS) at 3 V suggests that the Poole-Frenkel mechanism is the dominant conduction mechanism in the high field region. It was also observed that in the low electric field region Ohmic conduction is the dominant mechanism. Trap energy level (φt) of 0.36 eV, obtained from the Poole-Frenkel mechanism indicates that the defect is oxygen-related and is a good match with the reported value for V−/V−− in HfO2. Significant charge trapping at low level stress was observed whereas at high level and elevated temperature stressing suggests a variation of trap energy level indicating new defect formation. It is observed that the stress induced gate leakage current for the high temperature stressed devices is about three orders of magnitude more than that of room temperature stressed devices for the whole field range.
Multiscale monitoring of interface failure of brittle coating/ductile substrate systems: A non-destructive evaluation method combined digital image correlation with acoustic emission
Authors: Mao W. G. , Wu D. J. , Yao W. B. , Zhou M. , Lu C.
Published: October 2011

In this paper, we proposed a non-destructive evaluation method combined digital image correlation with acoustic emission techniques. The method was used to in situ monitor interface failure and internal damage of brittle coating/ductile substrate systems with different size scales. The results show that there is a good relationship between digital image correlation and acoustic emission signals, which can be applied to judge cracking formation and coating delamination and to determine fracture toughness of a thermal barrier coating system subjected to bending.
Impact of surface roughness on diffusion of confined fluids
Authors: Krekelberg William P. , Shen Vincent K. , Errington Jeffrey R. , Truskett Thomas M.
Published: October 2011

Using event-driven molecular dynamics simulations, we quantify how the self diffusivity of confined hard-sphere fluids depends on the nature of the confining boundaries. We explore systems with featureless confining boundaries that treat particle-boundary collisions in different ways and also various types of physically (i.e., geometrically) rough boundaries. We show that, for moderately dense fluids, the ratio of the self diffusivity of a rough wall system to that of an appropriate smooth-wall reference system is a linear function of the reciprocal wall separation, with the slope depending on the nature of the roughness. We also discuss some simple practical ways to use this information to predict confined hard-sphere fluid behavior in different rough-wall systems.
Enhanced charge collection in confined bulk heterojunction organic solar cells
Authors: Allen Jonathan E. , Yager Kevin G. , Hlaing Htay , Nam Chang-Yong , Ocko Benjamin M. , Black Charles T.
Published: October 2011

Confining blended poly(3-hexylthiophene) and [6,6]-phenyl-C61-butyric acid methyl ester organic solar cell active layers within nanometer-scale cylindrical pores nearly double the supported short-circuit photocurrent density compared to equivalent unconfined volumes of the same blend and increases the poly(3-hexylthiophene) hole mobility in the blend by nearly 500 times. Grazing incidence x-ray diffraction measurements show that the confinement changes the polymer orientation distribution, suppressing low charge conductivity orientations while simultaneously disrupting polymer ordering.
Electromechanical properties and anisotropy of single- and multi-domain 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 single crystals
Authors: Liu Gang , Jiang Wenhua , Zhu Jiaqi , Cao Wenwu
Published: October 2011

Complete sets of elastic, piezoelectric, and dielectric constants of 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 single crystal poled along [111]c (single domain) as well as non-polar axes [001]c and [011]c (multidomain) have been measured under natural conditions. These data allowed us to evaluate accurately the extrinsic contributions to the superior piezoelectric properties. Very large extrinsic contributions to the unusual anisotropies in multidomain crystals are confirmed. We found that the instability of domain structures is the origin of the low mechanical quality factor Q for the multidomain relaxor-based ferroelectric single crystals. Our results can provide useful guidance in future design of domain engineered materials.
Origin of intrinsic dark count in superconducting nanowire single-photon detectors
Authors: Yamashita T. , Miki S. , Makise K. , Qiu W. , Terai H. , Fujiwara M. , Sasaki M. , Wang Z.
Published: October 2011

The origin of the decoherence in superconducting nanowire single-photon detectors, the so-called dark count, was investigated. We measured the direct-current characteristics and bias-current dependencies of the dark count rate in a wide range of temperatures from 0.5 K to 4.0 K, and analyzed the results by theoretical models of thermal fluctuations of vortices. Our results indicate that the current-assisted unbinding of vortex-antivortex pairs is the dominant origin of the dark count.
Spin pumping by parametrically excited short-wavelength spin waves
Authors: Kurebayashi H. , Dzyapko O. , Demidov V. E. , Fang D. , Ferguson A. J. , Demokritov S. O.
Published: October 2011

We use both parallel and perpendicular parametric pumping techniques to excite short-wavelength spin waves in an yttrium iron garnet film and study the spin current generation from spin waves excited by these pumping methods with the help of the inverse spin-Hall effect in the adjacent Pt layer. We observed clear spin current generations for these pumping techniques and find that the efficiency is nearly independent of the magnitude and the direction of the wave vectors of excited spin waves. These experimental results are important for future spintronic devices operated by short-wavelength spin waves.
Disorder effect on the electronic and magnetic properties of Sr2FeCoO6: A density-functional theoretical investigation
Authors: Wu Haiping , Wang Lili , Qian Yan , Tan Weishi , Xiao Chuanyun , Deng Kaiming
Published: October 2011

Using density-functional calculations within the generalized gradient approximation plus U framework, the electronic and magnetic properties of the ordered and the disordered Sr2FeCoO6 are investigated systematically. The results show that all disordered Sr2FeCoO6 have ferromagnetic ground state, as that of the ordered one. The magnetic coupling of both Fe and Co sublattices remains ferromagnetic, and the two sublattices are coupled ferromagnetically as well. Most interestingly, the disorder leads to the substantial increase of the magnetic moments on both Fe and Co sites comparing with those of the ordered Sr2FeCoO6. It is also significantly found that the disorder can control the transport property, decreasing the half-metallic band gap of the ordered Sr2FeCoO6 and even giving rise to a half-metal to metal transition at a critical level of disorder.
Diffusion of tin in germanium: A GGA+U approach
Authors: Tahini H. , Chroneos A. , Grimes R. W. , Schwingenschlögl U.
Published: October 2011

Density functional theory calculations are used to investigate the formation and diffusion of tin-vacancy pairs (SnV) in germanium (Ge). Depending upon the Fermi energy, SnV pairs can form in neutral, singly negative, or doubly negative charged states. The activation energies of diffusion, also as function of the Fermi energy, are calculated to lie between 2.48-3.65 eV, in agreement with and providing an interpretation of available experimental work.
Spectroscopic measurement of electric field in atmospheric-pressure plasma jet operating in bullet mode
Authors: Sretenović Goran B. , Krstić Ivan B. , Kovačević Vesna V. , Obradović Bratislav M. , Kuraica Milorad M.
Published: October 2011

Atmospheric-pressure helium plasma jet operating in the bullet/streamer mode has been studied using optical emission spectroscopy. Electric field strength distribution is measured using Stark polarization spectroscopy of He I 492.19 nm line. It is shown that the electric field is almost constant along the jet axis. Measured electric field distribution is in agreement with theoretical predictions of streamer propagation in helium jets at atmospheric pressure. Obtained radial distribution of the axial electric field shows that the ring-shaped structure of the light emission is a consequence of such electric field distribution.
Virtual Mie particle model of laser damage to optical elements
Authors: Hirata Kazuya , Haraguchi Koshi
Published: October 2011

In recent years, devices being developed for application systems have used laser beams that have high average power, high peak power, short pulse width, and short wavelength. Therefore, optical elements using such application systems require a high laser damage threshold. The laser damage threshold is provided by International Organization for Standardization 11254 (ISO11254). One of the measurement methods of the laser damage threshold provided by ISO11254 is an online method to measure the intensity of light scattering due to a laser damage trace. In this paper, we propose a measurement method for the laser damage threshold that realizes high sensitivity and high accuracy by using polarized light and lock-in detection. Since the scattering light with laser damage is modeled on the asperity of the optical element-surface as Mie particles (virtual Mie particles), we consider the intensity change of scattering light as a change in the radius of a virtual Mie particle. To evaluate this model, the laser damage trace on the optical element-surface was observed by an atomic force microscopy (AFM). Based on the observed AFM image, we analyzed the frequency domain by the Fourier transform, and estimated the dominant virtual Mie particle radius in the AFM measurement area. In addition, we measured the laser damage threshold. The light source was the fifth generation of a Nd:YAG laser (λ =213nm). The specifications of the laser were: repetition frequency 10Hz, pulse width 4ns, linear type polarization, laser pulse energy 4mJ, and laser transverse mode TEM00. The laser specifications were a repetition frequency, pulse width, pulse energy and beam diameter of 10Hz, 4ns, 4mJ and 13mm, respectively. The laser damage thresholds of an aluminum coated mirror and a dielectric multi-layer mirror designed at a wavelength of 213nm as measured by this method were 0.684 J/cm2 and 0.998J/cm2, respectively. These laser damage thresholds were 1/4 the laser damage thresholds measured based on ISO11254. We concluded that this evaluation of laser damage enabled us to detect laser damage traces that were smaller than the diffraction limitation.
Investigation of Ge1-xSnx/Ge with high Sn composition grown at low-temperature
Authors: Yu I. S. , Wu T. H. , Wu K. Y. , Cheng H. H. , Mashanov V. I. , Nikiforov A. I. , Pchelyakov O. P. , Wu X. S.
Published: October 2011

We report on experimental investigations of the growth of Ge1-xSnx film with thickness above the critical thickness using Molecular Beam Epitaxy. A series of Ge1-xSnx films with various Sn compositions up to 14% are deposited on a Ge buffer layer for growth at low temperatures close to the melting point of Sn. Analysis of various measurements shows that the Ge1-xSnx film is defect free in the XTEM image and that Sn is distributed almost uniformly in the film for Sn compositions up to 9.3%. The Sn composition of the films is higher than the Sn composition that is theoretically predicted to cause the energy band of Ge to change from an indirect to a direct bandgap; thus, the present investigation provides a method for growing direct bandgap GeSn film, which is desired for use in applications involving optoelectronic devices.
Synthesis and characterization of copper, polyimide and TIPS-pentacene layers for the development of a solution processed fibrous transistor
Authors: Van Genabet B. , Schwarz A. , Bruneel E. , Rambausek L. , Van Driessche I. , Van Langenhove L.
Published: October 2011

A study was performed for the development of a flexible organic field effect transistor starting from a polyester fibre as substrate material. Focus of subsequent layer deposition was on low temperature soluble processes to allow upscaling. Gate layer consists out of a pyrrole polymerization and copper coating step. Polyimide dielectric layer was deposited using dipcoating. Gold electrodes were vacuum evaporated and patterned via mask fibre shadowing. The active layer consisted of a soluble p-type TIPS-pentacene organic semiconductor. Different deposition techniques have been examined. Considerable progress in development of a transistor has been made.
Molecular study of worldwide distribution and diversity of soil animals
Authors: Wu Tiehang , Ayres Edward , Bardgett Richard D. , Wall Diana H. , Garey James R.
Published: October 2011

The global distribution of soil animals and the relationship of below-ground biodiversity to above-ground biodiversity are not well understood. We examined 17,516 environmental 18S rRNA gene sequences representing 20 phyla of soil animals sampled from 11 locations covering a range of biomes and latitudes around the world. No globally cosmopolitan taxa were found and only 14 of 2,259 operational taxonomic units (OTUs) found were common to four or more locations. Half of those were circumpolar and may reflect higher connectivity among circumpolar locations compared with other locations in the study. Even when OTU assembly criteria were relaxed to approximate the family taxonomic level, only 34 OTUs were common to four or more locations. A comparison of our diversity and community structure data to environmental factors suggests that below-ground animal diversity may be inversely related to above-ground biodiversity. Our data suggest that greater soil inorganic N and lower pH could explain the low below-ground biodiversity found at locations of high above-ground biodiversity. Our locations could also be characterized as being dominated by microarthropods or dominated by nematodes. Locations dominated by arthropods were primarily forests with lower soil pH, root biomass, mean annual temperature, low soil inorganic N and higher C:N, litter and moisture compared with nematode-dominated locations, which were mostly grasslands. Overall, our data indicate that small soil animals have distinct biogeographical distributions and provide unique evidence of the link between above-ground and below-ground biodiversity at a global scale.
The supply chain of CO2emissions
Authors: Davis Steven J. , Peters Glen P. , Caldeira Ken
Published: October 2011

CO2emissions from the burning of fossil fuels are conventionally attributed to the country where the emissions are produced (i.e., where the fuels are burned). However, these production-based accounts represent a single point in the value chain of fossil fuels, which may have been extracted elsewhere and may be used to provide goods or services to consumers elsewhere. We present a consistent set of carbon inventories that spans the full supply chain of global CO2emissions, finding that 10.2 billion tons CO2or 37% of global emissions are from fossil fuels traded internationally and an additional 6.4 billion tons CO2or 23% of global emissions are embodied in traded goods. Our results reveal vulnerabilities and benefits related to current patterns of energy use that are relevant to climate and energy policy. In particular, if a consistent and unavoidable price were imposed on CO2emissions somewhere along the supply chain, then all of the parties along the supply chain would seek to impose that price to generate revenue from taxes collected or permits sold. The geographical concentration of carbon-based fuels and relatively small number of parties involved in extracting and refining those fuels suggest that regulation at the wellhead, mine mouth, or refinery might minimize transaction costs as well as opportunities for leakage.
Early Archean serpentine mud volcanoes at Isua, Greenland, as a niche for early life
Authors: Pons Marie-Laure , Quitté Ghylaine , Fujii Toshiyuki , Rosing Minik T. , Reynard Bruno , Moynier Frederic , Douchet Chantal , Albarède Francis
Published: October 2011

The Isua Supracrustal Belt, Greenland, of Early Archean age (3.81–3.70 Ga) represents the oldest crustal segment on Earth. Its complex lithology comprises an ophiolite-like unit and volcanic rocks reminiscent of boninites, which tie Isua supracrustals to an island arc environment. We here present zinc (Zn) isotope compositions measured on serpentinites and other rocks from the Isua supracrustal sequence and on serpentinites from modern ophiolites, midocean ridges, and the Mariana forearc. In stark contrast to modern midocean ridge and ophiolite serpentinites, Zn in Isua and Mariana serpentinites is markedly depleted in heavy isotopes with respect to the igneous average. Based on recent results of Zn isotope fractionation between coexisting species in solution, the Isua serpentinites were permeated by carbonate-rich, high-pH hydrothermal solutions at medium temperature (100–300 °C). Zinc isotopes therefore stand out as a pH meter for fossil hydrothermal solutions. The geochemical features of the Isua fluids resemble the interstitial fluids sampled in the mud volcano serpentinites of the Mariana forearc. The reduced character and the high pH inferred for these fluids make Archean serpentine mud volcanoes a particularly favorable setting for the early stabilization of amino acids.
Antitumorigenic potential of STAT3 alternative splicing modulation
Authors: Zammarchi Francesca , de Stanchina Elisa , Bournazou Eirini , Supakorndej Teerawit , Martires Kathryn , Riedel Elyn , Corben Adriana D. , Bromberg Jacqueline F. , Cartegni Luca
Published: October 2011

Signal transducer and activator of transcription 3 (
STAT3
) plays a central role in the activation of multiple oncogenic pathways. Splicing variant STAT3β uses an alternative acceptor site within exon 23 that leads to a truncated isoform lacking the C-terminal transactivation domain. Depending on the context, STAT3β can act as a dominant-negative regulator of transcription and promote apoptosis. We show that modified antisense oligonucleotides targeted to a splicing enhancer that regulates STAT3 exon 23 alternative splicing specifically promote a shift of expression from STAT3α to STAT3β. Induction of endogenous STAT3β leads to apoptosis and cell-cycle arrest in cell lines with persistent STAT3 tyrosine phosphorylation compared with total STAT3 knockdown obtained by forced splicing-dependent nonsense-mediated decay (FSD-NMD). Comparison of the molecular effects of splicing redirection to STAT3 knockdown reveals a unique STAT3β signature, with a down-regulation of specific targets (including lens epithelium-derived growth factor, p300/CBP-associated factor, CyclinC, peroxisomal biogenesis factor 1, and STAT1β) distinct from canonical STAT3 targets typically associated with total STAT3 knockdown. Furthermore, similar in vivo redirection of STAT3 alternative splicing leads to tumor regression in a xenograft cancer model, demonstrating how pharmacological manipulation of a single key splicing event can manifest powerful antitumorigenic properties and validating endogenous splicing reprogramming as an effective cancer therapeutic approach.
Tobacco nicotine uptake permease (NUP1) affects alkaloid metabolism
Authors: Hildreth Sherry B. , Gehman Elizabeth A. , Yang Haibing , Lu Rong-He , K C Ritesh , Harich Kim C. , Yu Shi , Lin Jinshan , Sandoe Jackson L. , Okumoto Sakiko , Murphy Angus S. , Jelesko John G.
Published: October 2011

An effective plant alkaloid chemical defense requires a variety of transport processes, but few alkaloid transporters have been characterized at the molecular level. Previously, a gene fragment encoding a putative plasma membrane proton symporter was isolated, because it was coordinately regulated with several nicotine biosynthetic genes. Here, we show that this gene fragment corresponds to a
Nicotiana tabacum
gene encoding a nicotine uptake permease (NUP1). NUP1 belongs to a plant-specific class of purine uptake permease-like transporters that originated after the bryophytes but before or within the lycophytes. NUP1 expressed in yeast cells preferentially transported nicotine relative to other pyridine alkaloids, tropane alkaloids, kinetin, and adenine. NUP1-GFP primarily localized to the plasma membrane of tobacco Bright Yellow-2 protoplasts. WT
NUP1
transcripts accumulated to high levels in the roots, particularly in root tips.
NUP1-RNAi
hairy roots had reduced
NUP1
mRNA accumulation levels, reduced total nicotine levels, and increased nicotine accumulation in the hairy root culture media. Regenerated
NUP1-RNAi
plants showed reduced foliar and root nicotine levels as well as increased seedling root elongation rates. Thus, NUP1 affected nicotine metabolism, localization, and root growth.
Macroalgal terpenes function as allelopathic agents against reef corals
Authors: Rasher Douglas B. , Stout E. Paige , Engel Sebastian , Kubanek Julia , Hay Mark E.
Published: October 2011

During recent decades, many tropical reefs have transitioned from coral to macroalgal dominance. These community shifts increase the frequency of algal–coral interactions and may suppress coral recovery following both anthropogenic and natural disturbance. However, the extent to which macroalgae damage corals directly, the mechanisms involved, and the species specificity of algal–coral interactions remain uncertain. Here, we conducted field experiments demonstrating that numerous macroalgae directly damage corals by transfer of hydrophobic allelochemicals present on algal surfaces. These hydrophobic compounds caused bleaching, decreased photosynthesis, and occasionally death of corals in 79% of the 24 interactions assayed (three corals and eight algae). Coral damage generally was limited to sites of algal contact, but algae were unaffected by contact with corals. Artificial mimics for shading and abrasion produced no impact on corals, and effects of hydrophobic surface extracts from macroalgae paralleled effects of whole algae; both findings suggest that local effects are generated by allelochemical rather than physical mechanisms. Rankings of macroalgae from most to least allelopathic were similar across the three coral genera tested. However, corals varied markedly in susceptibility to allelopathic algae, with globally declining corals such as
Acropora
more strongly affected. Bioassay-guided fractionation of extracts from two allelopathic algae led to identification of two loliolide derivatives from the red alga
Galaxaura filamentosa
and two acetylated diterpenes from the green alga
Chlorodesmis fastigiata
as potent allelochemicals. Our results highlight a newly demonstrated but potentially widespread competitive mechanism to help explain the lack of coral recovery on many present-day reefs.
Inflammasome activation and IL-1β target IL-1α for secretion as opposed to surface expression
Authors: Fettelschoss Antonia , Kistowska Magdalena , LeibundGut-Landmann Salomé , Beer Hans-Dietmar , Johansen Pål , Senti Gabriela , Contassot Emmanuel , Bachmann Martin F. , French Lars E. , Oxenius Annette , Kündig Thomas M.
Published: October 2011

Interleukin-1α (IL-1α) and -β both bind to the same IL-1 receptor (IL-1R) and are potent proinflammatory cytokines. Production of proinflammatory (pro)–IL-1α and pro–IL-1β is induced by Toll-like receptor (TLR)-mediated NF-κB activation. Additional stimulus involving activation of the inflammasome and caspase-1 is required for proteolytic cleavage and secretion of mature IL-1β. The regulation of IL-1α maturation and secretion, however, remains elusive. IL-1α exists as a cell surface-associated form and as a mature secreted form. Here we show that both forms of IL-1α, the surface and secreted form, are differentially regulated. Surface IL-1α requires NF-κB activation only, whereas secretion of mature IL-1α requires additional activation of the inflammasome and caspase-1. Surprisingly, secretion of IL-1α also required the presence of IL-1β, as demonstrated in IL-1β–deficient mice. We further demonstrate that IL-1β directly binds IL-1α, thus identifying IL-1β as a shuttle for another proinflammatory cytokine. These results have direct impact on selective treatment modalities of inflammatory diseases.
Active
opsin
loci adopt intrachromosomal loops that depend on the photoreceptor transcription factor network
Authors: Peng Guang-Hua , Chen Shiming
Published: October 2011

Rod and cone
opsin
genes are expressed in a mutually exclusive manner in their respective photoreceptor subtypes in the mammalian retina. Previous transgenic mouse studies showed that functional interactions between the distal enhancer and proximal promoter of rhodopsin and long/medium-wavelength (L/M)
opsin
genes are essential for regulating their cell-type–specific transcription. We have used chromosomal conformation capture assays in mouse retinas to investigate the molecular mechanism responsible for this interaction. Here we show that each
opsin
gene forms intrachromosomal loops in the appropriate photoreceptor subtype, while maintaining a linear configuration in other cell types where it is silent. The enhancer forms physical contacts not only with the promoter but also with the coding regions of each
opsin
locus. ChIP assays showed that cell-type–specific target binding by three key photoreceptor transcription factors—cone–rod homeobox (CRX), neural retina leucine zipper (NRL), and nuclear receptor subfamily 2, group E, member 3 (NR2E3)—is required for the appropriate local chromosomal organization and transcription of rod and cone
opsins
. Similar correlations between chromosomal loops and active transcription of
opsin
genes were also observed in human photoreceptors. Furthermore, quantitative chromosomal conformation capture on human retinas from two male donors showed that the
L
/
M
enhancer
locus control region
(
LCR
) loops with either the
L
or
M
promoter in a near 3:1 ratio, supporting distance-dependent competition between
L
and
M
for
LCR
. Altogether, our results suggest that the photoreceptor transcription factor network cooperatively regulates the chromosomal organization of target genes to precisely control photoreceptor subtype-specific gene expression.
Langerhans cells are precommitted to immune tolerance induction
Authors: Shklovskaya Elena , O’Sullivan Brendan J. , Ng Lai Guan , Roediger Ben , Thomas Ranjeny , Weninger Wolfgang , Fazekas de St Groth Barbara
Published: October 2011

Antigen-dependent interactions between T lymphocytes and dendritic cells (DCs) can produce two distinct outcomes: tolerance and immunity. It is generally considered that all DC subsets are capable of supporting both tolerogenic and immunogenic responses, depending on their exposure to activating signals. Here, we tested whether epidermal Langerhans cells (LCs) can support immunogenic responses in vivo in the absence of antigen presentation by other DC subsets. CD4 T cells responding to antigen presentation by activated LCs initially proliferated but then failed to differentiate into effector/memory cells or to survive long term. The tolerogenic function of LCs was maintained after exposure to potent adjuvants and occurred despite up-regulation of the costimulatory molecules CD80, CD86, and IL-12, but was consistent with their failure to translocate the NF-κB family member RelB from the cytoplasm to the nucleus. Commitment of LCs to tolerogenic function may explain why commensal microorganisms expressing Toll-like receptor (TLR) ligands but confined to the skin epithelium are tolerated, whereas invading pathogens that breach the epithelial basement membrane and activate dermal DCs stimulate a strong immune response.