bluuebunny/crossref_metadata_2025 huggingface dataset:
Directly measured heating rates of a tropical subvisible cirrus cloud
Authors: Bucholtz Anthony , Hlavka Dennis L. , McGill Matthew J. , Schmidt K. Sebastian , Pilewskie Peter , Davis Sean M. , Reid Elizabeth A. , Walker Annette L.
Published: August 2010

We present the first direct measurements of the infrared and solar heating rates of a tropical subvisible cirrus (SVC) cloud sampled off the east coast of Nicaragua on 25 July 2007 by the NASA ER‐2 aircraft during the Tropical Composition, Cloud and Climate Coupling Experiment (TC4). On this day a persistent thin cirrus layer, with mostly clear skies underneath, was detected in real time by the cloud lidar on the ER‐2, and the aircraft was directed to profile down through the SVC. Measurements of the net broadband infrared irradiance and spectrally integrated solar irradiance above, below, and through the SVC are used to determine the infrared and solar heating rates of the cloud. The lidar measurements show that the variable SVC layer was located between ∼13 and 15 km. Its midvisible optical depth varied from 0.01 to 0.10 with a mean of 0.034 ± 0.033. Its depolarization ratio was approximately 0.4, indicative of ice clouds. From the divergence of the measured net irradiances the infrared heating rate of the SVC was determined to be ∼2.50–3.24 K d−1 and the solar heating rate was found to be negligible. These values are consistent with previous indirect observations of other SVC and with model‐generated heating rates of SVC with similar optical depths. This study illustrates the utility and potential of the profiling sampling strategy employed here. A more fully instrumented high‐altitude aircraft that also included in situ cloud and aerosol probes would provide a comprehensive data set for characterizing both the radiative and microphysical properties of these ubiquitous tropical clouds.
A climatology of aerosol optical and microphysical properties over the Indian subcontinent from 9 years (2000–2008) of Multiangle Imaging Spectroradiometer (MISR) data
Authors: Dey Sagnik , Di Girolamo Larry
Published: August 2010

We present the first detailed analysis of a 9 year (2000–2008) seasonal climatology of size‐ and shape‐segregated aerosol optical depth (AOD) and Ångström exponent (AE) over the Indian subcontinent derived from the Multiangle Imaging Spectroradiometer (MISR). Our analysis is evaluated against in situ observations to better understand the error characteristics of and to corroborate much of the space‐time variability found within the MISR aerosol properties. The space‐time variability is discussed in terms of aerosol sources, meteorology, and topography. We introduce indices based on aerosol size‐ and shape‐segregated optical depth and their effect on AE that describe the relative seasonal change in anthropogenic and natural aerosols from the preceding season. Examples of major new findings include the following: (1) winter to premonsoon changes in aerosol properties are not just dominated by an increase in dust, as previously thought, but also by an increase in anthropogenic components, particularly in regions where biomass combustion is prevalent; (2) ∼15% of the AOD over the high wintertime pollution in the eastern Indo‐Gangetic basin is due to large dust particles, resulting in the lowest AE (<0.8) over India in this season and likely caused by rural activities (e.g., agriculture, etc.) from the densely populated rural area; (3) while AOD decreases from the Indo‐Gangetic basin up to the Tibetan Plateau, a large peak in AE and the fraction of AOD due to particle radii <0.7 μm exists in the foothills of the Himalayas, particularly in the premonsoon season; and (4) the AOD due to nonspherical particles exhibits a strong ocean‐to‐land gradient over all seasons because of topographical and meteorological controls.
Temporal controls on dissolved organic matter and lignin biogeochemistry in a pristine tropical river, Democratic Republic of Congo
Authors: Spencer Robert G. M. , Hernes Peter J. , Ruf Rosmarie , Baker Andy , Dyda Rachael Y. , Stubbins Aron , Six Johan
Published: August 2010

Dissolved organic carbon (DOC), lignin biomarkers, and the optical properties of dissolved organic matter (DOM) were measured in the Epulu River (northeast Democratic Republic of Congo) with the aim of investigating temporal controls on the quantity and chemical composition of DOM in a tropical rainforest river. Three different periods defined by stages of the hydrologic regime of the region, (1) post dry flushing period, (2) intermediary period, and (3) start of the dry period/post flush, were sampled. Temporal variability in DOM quantity and quality was observed with highest DOC, lignin concentration (Σ8) and carbon‐normalized (Λ8) values during the flushing period attributed to greater surface runoff and leaching of organic‐rich horizons, with lowest values in the dry period/post flush once source materials were well leached. Chromophoric DOM (CDOM) was strongly correlated to DOC and Σ8 (r2 = 0.85 and 0.83, respectively; p < 0.001), and CDOM quality measurements (SUVA254, spectral slope ratio and fluorescence index) were strongly correlated to Λ8 values (r2 = 0.77, 0.69, and 0.75, respectively; p < 0.001), demonstrating the ability to derive DOC and lignin export and to track DOM quality in tropical riverine systems from simple optical measurements. This study demonstrates similar effects in the variability of DOM quantity and quality due to changing hydrologic inputs for a tropical river as has been previously reported for temperate and northern high‐latitude rivers. Therefore, flushing periods in tropical rivers warrant further study, as they are critical toward understanding ecosystem biogeochemistry as maximal export of freshly leached plant material occurs during this time period.
Measurement and prediction of the relationship between capillary pressure, saturation, and interfacial area in a NAPL‐water‐glass bead system
Authors: Porter Mark L. , Wildenschild Dorthe , Grant Gavin , Gerhard Jason I.
Published: August 2010

In this work, the constitutive relationship between capillary pressure (Pc), saturation (Sw), and fluid‐fluid interfacial area per volume (IFA) is characterized using computed microtomography for drainage and imbibition experiments consisting of a nonaqueous phase liquid and water. The experimentally measured relationship was compared to a thermodynamic model that relates the area under the Pc − Sw curve to the total IFA, an, and the capillary‐associated IFA, anw. Surfaces were fit to the experimental and modeled Pc − Sw − an and Pc − Sw − anw data in order to characterize the relationship in three dimensions (3D). For the experimental system, it was shown that the Pc − Sw − an relationship does not exhibit hysteresis. The model is found to provide a reasonable approximation of the magnitude of the 3D surfaces for an and anw, with a mean absolute percent error of 26% and 15%, respectively. The relatively high mean absolute percent errors are primarily the result of discrepancies observed at the wetting‐ and nonwetting‐phase residual saturation values. Differences in the shapes of the surfaces are noted, particularly in the curvature (arising from the addition of scanning curves and presence of an − Sw hysteresis in the predicted results) and endpoints (particularly the inherent nature of thermodynamic models to predict significant anw associated with residual nonwetting‐phase saturation). Overall, the thermodynamic model is shown to be a practical, inexpensive tool for predicting the Pc − Sw − an and Pc − Sw − anw surfaces from Pc − Sw data.
A global forest canopy height map from the Moderate Resolution Imaging Spectroradiometer and the Geoscience Laser Altimeter System
Authors: Lefsky Michael A.
Published: August 2010

The value of lidar derives from its ability to map ecosystem vertical structure which can be used to estimate aboveground carbon storage. Spaceborne lidar sensors collect data along transects and gain value for the global change science community when combined with data sources that have complete horizontal coverage. Data sources and methods for this type of analysis require evaluation. In this work we use image segmentation of 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) data to produce a global map of 4.4 million forest patches. Where a Geoscience Laser Altimeter System (GLAS) transect intersects a patch, its height is calculated from the GLAS observations directly. Regression analysis is then used to estimate the heights of those patches without GLAS observations. Regression goodness‐of‐fit statistics indicate moderately strong relationships for predicting the 90th percentile patch height, with a mean RMSE of 5.9 m and mean correlation (R2) of 0.67.
Pelagic and coastal sources of P‐wave microseisms: Generation under tropical cyclones
Authors: Zhang Jian , Gerstoft Peter , Bromirski Peter D.
Published: August 2010

Nonlinear wave‐wave interactions generate double‐frequency (DF) microseisms, which include both surface waves (mainly Rayleigh‐type) and compressional (P) waves. Although it is unclear whether DF surface waves generated in deep oceans are observed on land, we show that beamforming of land‐based seismic array data allows detection of DF P waves generated by ocean waves from Super Typhoon Ioke in both pelagic and coastal regions. Two distinct spectral bands associated with different P‐wave source locations are observed. The short‐period DF band (0.16–0.35 Hz) is dominated by P waves generated in the deep ocean by local wind seas under the storm. In contrast, P waves in the long‐period DF band (0.1–0.15 Hz) are weaker and generated closer to the coast of Japan from swell interactions. The accurate identification of DF P‐wave microseism source areas is useful to monitor ocean wave‐wave interactions due to tropical cyclones and to image Earth structure using ambient seismic noise.
Analysis of human and animal fecal microbiota for microbial source tracking
Authors: Lee Jung Eun , Lee Sunghee , Sung Joohon , Ko GwangPyo
Published: August 2010

Microbial compositions of human and animal feces from South Korea were analyzed and characterized. In total, 38 fecal samples (14 healthy adult humans, 6 chickens, 6 cows, 6 pigs and 6 geese) were analyzed by 454 pyrosequencing of the V2 region of the 16S rRNA gene. Four major phyla, Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes, were identified in the samples. Principal coordinate analysis suggested that microbiota from the same host species generally clustered, with the exception of those from humans, which exhibited sample-specific compositions. A network-based analysis revealed that several operational taxonomic units (OTUs), such as Lactobacillus sp., Clostridium sp. and Prevotella sp., were commonly identified in all fecal sources. Other OTUs were present only in fecal samples from a single organism. For example, Yania sp. and Bifidobacterium sp. were identified specifically in chicken and human fecal samples, respectively. These specific OTUs or their respective biological markers could be useful for identifying the sources of fecal contamination in water by microbial source tracking.
Identity of epibiotic bacteria on symbiontid euglenozoans in O2-depleted marine sediments: evidence for symbiont and host co-evolution
Authors: Edgcomb V P , Breglia S A , Yubuki N , Beaudoin D , Patterson D J , Leander B S , Bernhard J M
Published: August 2010

A distinct subgroup of euglenozoans, referred to as the ‘Symbiontida,’ has been described from oxygen-depleted and sulfidic marine environments. By definition, all members of this group carry epibionts that are intimately associated with underlying mitochondrion-derived organelles beneath the surface of the hosts. We have used molecular phylogenetic and ultrastructural evidence to identify the rod-shaped epibionts of the two members of this group, Calkinsia aureus and B.bacati, hand-picked from the sediments of two separate oxygen-depleted, sulfidic environments. We identify their epibionts as closely related sulfur or sulfide-oxidizing members of the epsilon proteobacteria. The epsilon proteobacteria generally have a significant role in deep-sea habitats as primary colonizers, primary producers and/or in symbiotic associations. The epibionts likely fulfill a role in detoxifying the immediate surrounding environment for these two different hosts. The nearly identical rod-shaped epibionts on these two symbiontid hosts provides evidence for a co-evolutionary history between these two sets of partners. This hypothesis is supported by congruent tree topologies inferred from 18S and 16S rDNA from the hosts and bacterial epibionts, respectively. The eukaryotic hosts likely serve as a motile substrate that delivers the epibionts to the ideal locations with respect to the oxic/anoxic interface, whereby their growth rates can be maximized, perhaps also allowing the host to cultivate a food source. Because symbiontid isolates and additional small subunit rDNA gene sequences from this clade have now been recovered from many locations worldwide, the Symbiontida are likely more widespread and diverse than presently known.
Variations in Intensity, Fundamental Frequency, and Voicing for Teachers in Occupational Versus Nonoccupational Settings
Authors: Hunter Eric J. , Titze Ingo R.
Published: August 2010

Purpose

In this study, the authors created a more concise picture of the vocal demands placed on teachers by comparing occupational voice use with nonoccupational voice use.

Method

The authors used National Center for Voice and Speech voice dosimetry databank to calculate voicing percentage per hour as well as average dB SPL and fundamental frequency (F
0
). Occupational voice use (9:00 a.m.–3:00 p.m., weekdays) and nonoccupational voice use (4:00 p.m.–10:00 p.m., weekends) were compared (57 teachers, 2 weeks each).

Results

Five key findings were uncovered: (1) Similar to previous studies, occupational voicing percentage per hour is more than twice that of nonoccupational voicing; (2) teachers experienced a wide range of occupational voicing percentages per hour (30 ± 11% per hr); (3) average occupational voice was about 1 dB SPL louder than the nonoccupational voice and remained constant throughout the day; (4) occupational voice exhibited an increased pitch and trended upward throughout the day; and (5) some apparent gender differences were shown.

Conclusions

Data regarding voicing percentages, F
0
, and dB SPL provide critical insight into teachers' vocal health. Further, because nonoccupational voice use is added to an already overloaded voice, it may add key insights into recovery patterns and should be the focus of future studies.
Time-resolved measurements of near infrared emission spectra from explosions: Pure pentaerythritol tetranitrate and its mixtures containing silver and aluminum particles
Authors: Koch Jon D. , Piecuch Scott , Lightstone James M. , Carney Joel R. , Hooper Joe
Published: August 2010

Measurements of chemical transients and thermodynamic conditions are difficult to obtain yet fundamentally important in understanding the behavior of explosives. We have constructed a fast near infrared (NIR) spectrometer and have made temporally and spectrally-resolved emission measurements during postdetonation combustion of pure pentaerythritol tetranitrate (PETN) charges and PETN charges doped with 10 wt % microparticles composed of silver (Ag) and aluminum (Al). We have observed postdetonation PETN emission spectra between 750 and 1500 nm at rates up to 46 992 spectra/s. The instrument captures the highly structured spectra immediately following breakout as well as the longer-lived broadband NIR emission signals from hot particles. The early spectra reveal spectral signatures related to PETN and the reacting constituents of the particles. The later spectra provide a means to infer the gray-body temperature history of the particles.
From nonlinear Schrödinger hierarchy to some (2+1)-dimensional nonlinear pseudodifferential equations
Authors: Yang Xiao , Du Dianlou
Published: August 2010

The Poisson structure on CN×RN is introduced to give the Hamiltonian system associated with a spectral problem which yields the nonlinear Schrödinger (NLS) hierarchy. The Hamiltonian system is proven to be Liouville integrable. Some (2+1)-dimensional equations including NLS equation, Kadomtesev–Petviashvili I (KPI) equation, coupled KPI equation, and modified Kadomtesev–Petviashvili (mKP) equation, are decomposed into Hamilton flows via the NLS hierarchy. The algebraic curve, Abel–Jacobi coordinates, and Riemann–Jacobi inversion are used to obtain the algebrogeometric solutions of these equations.
Spin glasslike behavior and magnetic enhancement in nanosized Ni–Zn ferrite system
Authors: Ghosh B. , Kumar S. , Poddar A. , Mazumdar C. , Banerjee S. , Reddy V. R. , Gupta A.
Published: August 2010

The effects of particle size, structure, microstrain, and cation distribution on magnetic property of nanosized Ni0.35Zn0.65Fe2O4 prepared through high-energy ball milling have been explored by a wide variety of experimental technique namely, x-ray diffraction, high-resolution transmission electron microscopy, dc magnetization measurement, and Mössbauer spectroscopy. The sample exhibits mixed magnetic behavior with a collective magnetic state between 300 and 60 K while spin glasslike freezing of magnetic moments has taken place below 60 K. The sample has displayed enhancement in magnetization, magnetic hyperfine field, coercivity, and anisotropy energy. The inherent superparamagnetic relaxation of ferrite nanoparticles has significantly reduced and it shows evidence of magnetic hysterisis at room temperature. These properties could be profitably used to overcome the inherent instability of magnetic nanoparticles. The intersublattice interaction (JAB) in the sample has strengthened due to migration of Fe3+ ions from octahedral (B) site to tetrahedral (A) site and this accounts for the genesis of counterintuitive magnetic enhancement in the sample.
Relaxation associated with the synergetic oxygen vacancies and electrons in (Ba1−xBix)0.9Sr0.1TiO3−δ ceramics
Authors: Li Zhuo , Fan Huiqing
Published: August 2010

The temperature dependence of dielectric properties of Bi-doped ceramics with (Ba0.95Bi0.05)0.9Sr0.1TiO3−δ and (Ba0.9Bi0.1)0.9Sr0.1TiO3−δ (abbreviated as BBST5 and BBST10, respec-tively) has been investigated, comparing with nondoped Ba0.9Sr0.1TiO3 (abbreviated as BST) ceramics. The dielectric relaxation behavior above 150 °C was observed in BBST5 and BBST10 ceramics with two broad dielectric loss peaks, which is very different from the BST ceramics with only one broad loss peak. The universal dielectric response (UDR) to the relaxation and P–E hysteresis loops, as well as J–E properties has been studied. The activation energy Ea with 0.83, 0.84 eV in the first dielectric loss peak P1 and 0.60, 0.65 eV in the second loss peak P2, and the exponent s in the UDR law decreasing with the increasing temperatures for BBST5 and BBST10 ceramics indicate that oxygen vacancies associated with electrons are responsible for the dielectric relaxation.
Energy transfer between Eu–Mn and photoluminescence properties of Ba0.75Al11O17.25–BaMgAl10O17:Eu2+,Mn2+ solid solution
Authors: Zhou Jun , Wang Yuhua , Liu Bitao , Li Feng
Published: August 2010

In order to evaluate the energy transfer between Eu–Mn in Ba0.75Al11O17.25–BaMgAl10O17 solid solution, Ba0.75Al11O17.25–BaMgAl10O17:Eu2+,Mn2+ phosphors were prepared by flux method. The crystal structure and the morphology of the solid solution were demonstrated by x-ray dirrfactometer and scanning electron microscopy. The photoluminescence mechanisms were explained by the energy transfer of Eu2+ to Mn2+ and the Dexter theory. A redshift of green emission peak and a decrease in decay time with the increase in Mn2+ concentration were observed. These phenomena are attributed to the formation of Mn2+ paired centers after analysis by a method of Pade approximations.
Impedance analysis for characterizing the influence of hydrostatic pressure on piezoelectric quartz crystal sensors
Authors: Cassiède M. , Daridon J.-L. , Paillol J. H. , Pauly J.
Published: August 2010

The effect of hydrostatic pressure on the electrical behavior of quartz crystal resonators vibrating in the megahertz range is investigated by impedance analysis. The responses in frequency and dissipation of five AT-cut polished quartz crystals immersed in helium gas are analyzed and compared from conductance spectra around the resonance on several overtones. A model is then proposed to correlate the variations in frequency and dissipation with pressure and to explain the particular behavior observed on the fundamental harmonic mode.
Quantitative carrier lifetime measurement with micron resolution
Authors: Gundel Paul , Heinz Friedemann D. , Schubert Martin C. , Giesecke Johannes A. , Warta Wilhelm
Published: August 2010

In the last fifteen years the measurement of the spatially resolved carrier lifetime has emerged as a valuable tool for the characterization of silicon wafers and solar cells. In most of the available measurement methods, the spatial resolution is constrained to the order of several 10 to 100 μm by the diffusion length of the charge carriers. In this paper we introduce a contactless quantitative technique to determine the Shockley–Read–Hall lifetime with a spatial resolution of 1 μm. This technique is based on high injection microphotoluminescence spectroscopy and allows a quantitative analysis of microscopic defects such as grain boundaries and metal precipitates by virtue of the high spatial resolution.
Fundamental study of mechanical energy harvesting using piezoelectric nanostructures
Authors: Sun Chengliang , Shi Jian , Wang Xudong
Published: August 2010

This paper numerically estimates the potential, the output power and the energy conversion efficiency of piezoelectric nanostructures, including rectangular nanowires (NWs), hexagonal NWs, and two-dimensional vertical thin films (the nanofins). Static analysis studies the maximum piezoelectric potential that can be produced by a BaTiO3 NW, a ZnO NW, and a ZnO nanofin when they are subjected to a constant external force. Dynamic analysis is performed to study the power generation ability via the vibration of these nanostructures agitated by ambient vibration energy. ZnO NW and nanofin are selected as two representative nanogenerator elements. Their dynamic responses are modeled using a single-degree of freedom system with a series of damping ratios. Combining the transfer functions of mechanical vibration and piezoelectric charge generation, we define the output power and efficiencies as functions of the vibration frequency and the sizes. The optimal size for constructing a high efficiency and high-power nanogenerator is suggested. The material dependence of a dynamic system is also studied based on different piezoelectric and ferroelectric material systems, including ZnO, BaTiO3, and (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3. This research reveals a comprehensive relationship between the mechanical energy harvesting ability and the nanomaterials’ morphologies, dimensions, and properties. It provides a guideline for the design of high-power nanogenerators and the development of piezoelectric nanodevices in general.
Orthosymplectically invariant functions in superspace
Authors: Coulembier K. , De Bie H. , Sommen F.
Published: August 2010

The notion of spherically symmetric superfunctions as functions invariant under the orthosymplectic group is introduced. This leads to dimensional reduction theorems for differentiation and integration in superspace. These spherically symmetric functions can be used to solve orthosymplectically invariant Schrödinger equations in superspace, such as the (an)harmonic oscillator or the Kepler problem. Finally, the obtained machinery is used to prove the Funk–Hecke theorem and Bochner’s relations in superspace.
Growth of Cu2O on Ga-doped ZnO and their interface energy alignment for thin film solar cells
Authors: Wong L. M. , Chiam S. Y. , Huang J. Q. , Wang S. J. , Pan J. S. , Chim W. K.
Published: August 2010

Cu 2 O thin films are deposited by direct current reactive magnetron sputtering on borofloat glass and indium tin oxide (ITO) coated glass at room temperature. The effect of oxygen partial pressure on the structures and properties of Cu2O thin films are investigated. We show that oxygen partial pressure is a crucial parameter in achieving pure phases of CuO and Cu2O. Based on this finding, we fabricate heterojunctions of p-type Cu2O with n-type gallium doped ZnO (GZO) on ITO coated glass substrates by pulsed laser deposition for GZO thin films. The energy band alignment for thin films of Cu2O/GZO on ITO glass is characterized using high-resolution x-ray photoelectron spectroscopy. The energy band alignment for the Cu2O/GZO heterojunctions is determined to be type II with a valence band offset of 2.82 eV and shows negligible effects of variation with gallium doping. The higher conduction band of the Cu2O relative to that of GZO in the obtained band alignment shows that the heterojunctions are suitable for solar cell application based on energy levels consideration.
Electron transport through Al–ZnO–Al: An ab initio calculation
Authors: Yang Zijiang , Wan Langhui , Yu Yunjin , Wei Yadong , Wang Jian
Published: August 2010

The electron transport properties of ZnO nanowires coupled by two aluminum electrodes were studied by ab initio method based on nonequilibrium Green’s function approach and density functional theory. A clearly rectifying current-voltage characteristics was observed. It was found that the contact interfaces between Al–O and Al–Zn play important roles in the charge transport at low bias voltage and give very asymmetric I-V characteristics. When the bias voltage increases, the negative differential resistance occurs at negative bias voltage. The charge accumulation was calculated and its behavior was found to be well correlated with the I-V characteristics. We have also calculated the electrochemical capacitance which exhibits three plateaus at different bias voltages which may have potential device application.
Mechanical behavior of a Zr-based metallic glass at elevated temperature under high strain rate
Authors: Liu W. D. , Liu K. X.
Published: August 2010

In current work, the mechanical behavior of a Zr-based bulk metallic glass at elevated temperatures (from 423 to 683 K) under high strain rate (from 5000 to 104 s−1) is investigated by an improved split Hopkinson pressure bar apparatus. Experimental results reveal that the failure stress goes down along with elevated temperature, while the strain rate dependency is relatively small. Furthermore, three different fracture modes are observed along with elevated temperature by scanning electron microscope (SEM). SEM observation results also indicate that the fractured specimen has been crystallized at temperature near Tg and the embrittlement caused by crystallization is attributed to the fracture mode changing.
Transparent p-type SnOx thin film transistors produced by reactive rf magnetron sputtering followed by low temperature annealing
Authors: Fortunato Elvira , Barros Raquel , Barquinha Pedro , Figueiredo Vitor , Park Sang-Hee Ko , Hwang Chi-Sun , Martins Rodrigo
Published: August 2010

P-type thin-film transistors (TFTs) using room temperature sputtered SnOx (x<2) as a transparent oxide semiconductor have been produced. The SnOx films show p-type conduction presenting a polycrystalline structure composed with a mixture of tetragonal β-Sn and α-SnOx phases, after annealing at 200 °C. These films exhibit a hole carrier concentration in the range of ≈1016–1018 cm−3; electrical resistivity between 101–102 Ω cm; Hall mobility around 4.8 cm2/V s; optical band gap of 2.8 eV; and average transmittance ≈85% (400 to 2000 nm). The bottom gate p-type SnOx TFTs present a field-effect mobility above 1 cm2/V s and an ON/OFF modulation ratio of 103.
Determination of the chiralities of isolated carbon nanotubes during superplastic elongation process
Authors: Hirahara Kaori , Inose Keita , Nakayama Yoshikazu
Published: August 2010

The structural changes in an isolated carbon nanotube during superplastic elongation are studied using a in situ transmission electron microscopy equipped with a nanomanipulation system. Nanobeam electron diffraction reveals the chiral indices of the nanotube decrease by (1, 1) when tensile stress and electroresistive heating are simultaneously applied. The change in the chiral indices corresponds to the migration of just two pairs of defects in the nanotube walls. The experiment allows the dynamics of plastic deformation to be understood at the atomistic level, which will be beneficial for constructing advanced devices with utilization of nanotubes.
Hydrogen vibrational modes on graphene and relaxation of the C–H stretch excitation from first-principles calculations
Authors: Sakong Sung , Kratzer Peter
Published: August 2010

Density functional theory (DFT) calculations are used to determine the vibrational modes of hydrogen adsorbed on graphene in the low-coverage limit. Both the calculated adsorption energy of a H atom of 0.8 eV and calculated C–H stretch vibrational frequency of 2552 cm−1 are unusually low for hydrocarbons, but in agreement with data from electron energy loss spectroscopy on hydrogenated graphite. The clustering of two adsorbed H atoms observed in scanning tunneling microscopy images shows its fingerprint also in our calculated spectra. The energetically preferred adsorption on different sublattices correlates with a blueshift of the C–H stretch vibrational modes in H adatom clusters. The C–H bending modes are calculated to be in the 1100 cm−1 range, resonant with the graphene phonons. Moreover, we use our previously developed methods to calculate the relaxation of the C–H stretch mode via vibration-phonon interaction, using the Born–Oppenheimer surface for all local modes as obtained from the DFT calculations. The total decay rate of the H stretch into other H vibrations, thereby creating or annihilating one graphene phonon, is determined from Fermi’s golden rule. Our calculations using the matrix elements derived from DFT calculations show that the lifetime of the H stretch mode on graphene is only several picoseconds, much shorter than on other semiconductor surfaces such as Ge(001) and Si(001).
Switching capability of double-sided grating with horizontal shift
Authors: Iizuka Hideo , Engheta Nader , Fujikawa Hisayoshi , Sato Kazuo , Takeda Yasuhiko
Published: August 2010

A TiO2 grating beam splitter on the SiO2 layer is designed using the modal analysis. Normal incident light couples to the −1st/+1st-order transmission diffraction with a 49.6% efficiency for each and with a 50° refraction angle that is larger than the critical angle for the SiO2-air interface. The SiO2 interlayer is sandwiched between the two gratings. The finite-integration-technique investigation shows its switching capability due to the quarter-period shift between the gratings, with the zeroth-order transmission smaller than 5% for the “off” state and larger than 95% for the “on” state from 553 to 654 nm wavelength regime.
Effects of simulated rainfall events on soil carbon transformation
Authors: Zhang Jiaying , Lin Zhongbing , Zhang Renduo , Shen Jing
Published: August 2010

The storage of carbon (C) in soils can be influenced by rainfall patterns that affect both inputs from plant productivity and losses through soil respiration. The aim of this study was to investigate the effect of rainfall on the soil C transformation. A laboratory experiment was conducted using soil columns with different treatments, including a control with constant water content, and rainfall treatments with applications of 3, 6, and 10 simulated rainfall events during an experimental period of 31 days. Results showed that pulses of soil respiration rates occurred after the first 3 rainfall events, associated with soil water content and CO2 concentration pulses in the soil profile, while subsequent rainfall events did not result in similar increases in CO2 concentrations and respiration rates. Relative to the control treatment, the treatments with low (3 rainfall events) and moderate (6 rainfall events) amounts of total water applied resulted in 181% and 72% increases, respectively, in cumulative CO2 emission. In contrast, the high frequency rainfall treatment with the greatest amount of water resulted in a 40% reduction in cumulative CO2 emission. Soil microbial biomass C slightly increased under treatments with low and moderate rainfall treatments, but decreased under the treatment with 10 rainfall events. The results indicate that rainfall events with a high frequency and increased amount of water, and associated saturation of soils, can significantly reduce soil C losses during the wet season. The rainfall frequency and amount are of importance in controlling soil C emissions and should be incorporated into models of soil C dynamics.
Congestion in chronic systolic heart failure is related to renal dysfunction and increased mortality
Authors: Damman Kevin , Voors Adriaan A. , Hillege Hans L. , Navis Gerjan , Lechat Philippe , van Veldhuisen Dirk J. , Dargie Henry J. ,   for the CIBIS‐2 Investigators and Committees
Published: August 2010

Aims

To investigate the relationship between signs and symptoms of congestion, renal impairment and outcome in chronic heart failure (CHF) patients.

Methods and results

The Cardiac Insufficiency Bisoprolol Study II included 2647 NYHA class III/IV CHF patients. Congestion was estimated by the presence of elevated jugular venous pressure, orthopnoea, ascites, or oedema. Glomerular filtration rate (eGFR) was estimated using the simplified modification of diet in renal disease (sMDRD) formula. The main outcome consisted of all‐cause mortality. Mean age was 61 ± 11 years, 80% of patients were male, and mean eGFR was 77 ± 31 mL/min/1.73 m2. A total of 1234 (47%) patients had at least one sign, and 10% of patients had more than three signs of congestion. Mean eGFR was lower in patients with signs of congestion (75 ± 30 vs. 79 ± 31 mL/min/1.73 m2, P < 0.001). In multivariable analysis, signs of congestion remained independently related to eGFR (P = 0.012). Mortality rates almost doubled from no signs to three or more signs of congestion (11 vs. 20%, respectively, P < 0.0001). Patients with any signs of congestion also had a worse outcome. Adjusted hazard ratio was 1.42 (1.14–1.77), P < 0.01 for mortality and 1.21 (1.05–1.39), P < 0.01 for the composite endpoint.

Conclusion

Signs and symptoms of congestion are associated with renal impairment and are independent determinants of prognosis in patients with CHF.
Epidemiology and clinical course of heart failure with preserved ejection fraction
Authors: Lam Carolyn S.P. , Donal Erwan , Kraigher‐Krainer Elisabeth , Vasan Ramachandran S.
Published: August 2010

Heart failure with preserved ejection fraction (HFPEF) is increasingly recognized as a major public health problem worldwide. Significant advances have been made in our understanding of the epidemiology of HFPEF over the past two decades, with the publication of numerous population‐based epidemiological studies, large heart failure registries, and randomized clinical trials. These recent studies have provided detailed characterization of larger numbers of patients with HFPEF than ever before. This review summarizes the state of current knowledge with regards to the disease burden, patient characteristics, clinical course, and outcomes of HFPEF. Despite the wealth of available data, substantive gaps in knowledge were identified. These gaps represent opportunities for further research in HFPEF, a syndrome that is clearly a rising societal burden and that is associated with substantial morbidity and mortality.
Auxetic behaviour from connected different-sized squares and rectangles
Authors: Grima Joseph N. , Manicaro Elaine , Attard Daphne
Published: August 2010

Auxetic materials exhibit the unusual property of becoming fatter when uniaxially stretched and thinner when uniaxially compressed (i.e. they exhibit a negative Poisson ratio; NPR), a property that may result in various enhanced properties. The NPR is the result of the manner in which particular geometric features in the micro- or nanostructure of the materials deform when they are subjected to uniaxial loads. Here, we propose and discuss a new model made from different-sized rigid rectangles, which rotate relative to each other. This new model has the advantage over existing models that it can be used to describe the properties of very different systems ranging from silicates and zeolites to liquid-crystalline polymers. We show that such systems can exhibit scale-independent auxetic behaviour for stretching in particular directions, with Poisson’s ratios being dependent on the shape and relative size of different rectangles in the model and the angle between them.
Parental access to children in care—the research messages
Authors: MARSH PETER
Published: August 2010

SUMMARY. The basic facts about access of parents to their children in care are simply stated: a significant number of children in care have parental access limited either deliberately or inadvertently, without professional or legal justification, and the result of this is that contact between parents and children withers, and may reduce to nothing. How much does this matter? How common is it? Why does it happen? These questions will be examined below. We shall see that access in care merits serious attention and highlights important issues concerning the role of the social services in the spectrum of professional support available to families with children. The article is based on a paper given in 1986 to a Family Rights Group study course on access to children in care
Social class, social disadvantage and child health
Authors: GRAHAM PHILIP
Published: August 2010

SUMMARY. The examination of the contribution of social factors to child health status by linking mortality and morbidity to social class as defined by parental occupation is critically reviewed. An alternative approach to examining links between health and social factors is proposed that consists in defining several basic environmental needs of children that must be met to ensure their health status is optimised. For each basic need (housing, income, diet, quality of affectionate care etc.) it is proposed that minimal criteria or a ‘bottom‐line’ be set below which it should be generally agreed that an unacceptable level of disadvantage exists. The approach is described in outline, but to a sufficient degree to demonstrate that it is already feasible in some respects, although clearly many details would need to be worked out in others
Children's credibility on camera: the influence of age and production factors
Authors: WESTCOTT HELEN L. , CLIFFORD BRIAN R. , DAVIES GRAHAM M.
Published: August 2010

SUMMARY. An experiment was conducted to examine whether the use of different camera shots‐medium or close‐up‐affected the way in which child witnesses were perceived by adult raters. School children were video‐recorded describing an event in which they had participated, and students rated the children s perceived credibility on a number of scales. Type of shot used did not influence perceived credibility in a consistent manner, although it did influence some aspects of a child's credibility when the child's age and/or sex was taken into account. Children seen in medium shot were judged more honest than children seen in close‐up. Age of the child was the most influential factor, with older children generally perceived as more credible than younger children; this effect was particularly noticeable for girls and children seen in medium shot. The relevance of the current study for the testimony of child witnesses is discussed in the light of current and proposed legal reforms.
The Child's Need to Learn a Culture1
Authors: Trevarthen Colwyn
Published: August 2010

SUMMARY:This article draws on many years of research into the development of communication, play and cooperation in the first year of life to argue that, from their very earliest days, babies are highly motivated to learn, and are profoundly influenced in their learning by the interplay or ‘protoconversations’ between themselves and their parents and carers. The acquisition of language and thus thinking and understanding is supported by a relationship that demands cooperation and negotiation between adult and small child, and the author emphasises the central role that emotions and their communication have in cognitive growth.
The Importance of Children in Social Policy‐danger signals from a greying society
Authors: Tomlinson John
Published: August 2010

THEME: Britain is an example of a developed country which is in danger of doing less for children and families as a result of the recent economic and social policies. In this article I echo and reinforce the address the World Council President has just given, which encouraged us towards self‐criticism, coherence and action.
Support for Openness in Adoption Placements‐What can we learn from New Zealand?
Authors: Phillips Rena
Published: August 2010

SUMMARY: The placement for adoption of older children and those with special needs brings into focus the practice of open adoption whereby there is some form of continuing contact, including face to face contact, between birth and adoptive families. This in turn raises issues about the support needed to maintain such links. The paper discusses the progress made in New Zealand towards open adoption. The views of social workers, birth and adoptive families on face to face contact are reported and arguments for and against post‐adoption support for open adoption are examined.
Conceptualising Child and Family Support: The Contribution of Honneth's Critical Theory of Recognition
Authors: Houston Stan , Dolan Pat
Published: August 2010

The role of social support in child welfare policy and practice continues to engender widespread debate. Yet the moral and philosophical underpinnings of this topical area have received less attention in the literature. This is of concern, not least because academic debates on the ‘politics of identity’ have a significant contribution to make to our understanding of self‐development and social justice. In this article the authors show how Axel Honneth's account of the ‘struggle for recognition’ can be adapted to invigorate theories of social support. The result is a conceptual framework for reflective practice that can illuminate, and interrogate, the moral and operational dimensions of preventative work with children and families.
Food in Foster Families: Care, Communication and Conflict
Authors: Rees Alyson , Holland Sally , Pithouse Andrew
Published: August 2010

This study explores the significance of food and mealtimes in relation to the transition into foster care and the therapeutic settling of the child in a new family. In doing so, we draw upon an in‐depth, qualitative case study of 10 experienced foster families in the UK focusing on what helped them to be successful. At the time of the study, there were 16 foster children, aged 9–16, living with the families. Data collection included semi‐structured qualitative interviews and audio‐diaries with all family members who wished to be involved as well as eco‐maps produced by the young people. Thematic analysis and data extracts are reproduced in the study to demonstrate that meals and food preferences can function to affirm identities, membership and boundaries of family life as well as provide a site of conflict and control.
Oxidative DNA damage and reporter gene mutation in the livers of gpt delta rats given non‐genotoxic hepatocarcinogens with cytochrome P450‐inducible potency
Authors: Tasaki Masako , Umemura Takashi , Suzuki Yuta , Hibi Daisuke , Inoue Tomoki , Okamura Toshiya , Ishii Yuji , Maruyama Soichi , Nohmi Takehiko , Nishikawa Akiyoshi
Published: August 2010

Previous reports have proposed that reactive oxygen species resulting from induction of cytochrome P450 (CYP) isozymes might be involved in the modes of action of hepatocarcinogens with CYP‐inducible potency. In the present study, we investigated 8‐hydroxydeoxyguanosine (8‐OHdG) levels, in vivo mutagenicity and glutathione S‐transferase placental form (GST‐P)‐positive foci in the livers of gpt delta rats treated with piperonyl butoxide (PBO) or phenobarbital (PhB) for 4 and 13 weeks. Significant elevations in Cyp 1A1 and Cyp 1A2 mRNA levels after PBO treatment, and in Cyp 2B1 mRNA levels after PBO or PhB treatment, appeared together with remarkable hepatomegaly through the experimental period. Time‐dependent and statistically significant increases in 8‐OHdG levels were observed in the PBO treatment group along with significant increases in proliferating cell nuclear antigen (PCNA)‐positive hepatocytes at 4 weeks, while no increase in 8‐OHdG levels was found in PhB‐treated rats. No changes in mutant frequencies of gpt and red/gam (Spi‐) genes in liver DNA from PBO‐ or PhB‐treated rats were observed at 4 or 13 weeks. A 13‐week exposure to either PBO or PhB did not affect the number and area of GST‐P‐positive hepatocytes. CYP 1A1 and 1A2 induction may be responsible for elevated levels of 8‐OHdG in PBO‐treated rats. However, neither GC:TA transversions nor deletion mutations, typically regarded as 8‐OHdG‐related mutations, were observed in any of the treated rats. We conclude that reactive oxygen species, possibly produced through CYP catalytic pathways, likely induced genomic DNA damage but did not give rise to permanent gene mutation. (Cancer Sci 2010; 101: 2525–2530)
Sciatic nerve block for children
Authors: McNICOL L. R.
Published: August 2010

This study aimed to establish whether it was practical to perform sciatic nerve block by the anterior approach in a group of children of different ages and weights. A total of 82 blocks were performed of which 78 (95.2%) were judged to have been successful. The technique of the block differed slightly from that used in adult practice, in that great reliance was placed on the loss of resistance felt as the needle point passed through the thigh muscles into the sciatic neurovascular compartment. There were no immediate or late complications associated with this block in any of the patients. It is concluded that the block is easy to perform and can produce reliable postoperative analgesia for most common operations on the foot and ankle in paediatric practice.
Serum alkaline phosphatase inheritance in the pigeon1
Authors: Brown Russell V. , Manley James H.
Published: August 2010

Serum alkaline phosphatase inheritance was studied in 126 racing homer pigeons {Columba livid). Discontinuous polyacrylamide electrophoresis was used. Gels were stained with Blue RR salts with alphanaphthyl phosphate as a substrate. Seven pheno‐types were found. Inheritance was postulated to be by four codominant alleles. Gene frequencies were: q.ApA, 0.284; qApB, 0.602; qApC, 0.45; and qApD, 0.68.
Haemolytic factor in bovine seminal vesicle fluid
Authors: Matoušek J. , Staněk R.
Published: August 2010

The haemolytic factor of bovine seminal fluid has a protein nature; it is present in the precipitate obtained by treating the fluid with alcohol‐ether, ammonium sulphate and rivanol; it occurs in three out of five protein fractions obtained by chromatographic separation on Sephadex G 100.

of Enzymatic treatment of seminal vesicle fluid by pronase caused total inactivation of the haemolytic factor. Chymotrypsin caused considerable damage, while a number other enzymes did not affect the activity of the haemolytic factor.