bluuebunny/crossref_metadata_2025 huggingface dataset:
Traumatic brain injury in the neonate, child and adolescent human: An overview of pathology
Authors: Maxwell William L.
Published: December 2011

In the middle of the last century it had been thought that a good recovery of function and behavior would occur after traumatic brain injury (TBI) in very young human beings. A recent major change in thinking states that early childhood TBI may result in a severe compromise of normal brain growth and development such that TBI, rather, may compromise later normal development resulting in a need for very long term patient care and management. The mechanisms of injury and pathology within the injured brain are reviewed and compared between when injury occurs at or close to the time of birth, in an infant, in a young child, in a child between ages 5 and 10, in young and older adolescents and in young adulthood. Our understanding of pathophysiological responses by cells of the human central nervous system has recently greatly increased but has really only served to illustrate the great complexity of interactions between different types of cell within the growing and developing CNS. The hypothesis is developed that the outcome for a very young patient differs with the relative state of development of injured cells at the locus of injury. And that the potential for either repair, re‐instatement of normal cellular and organ function or for continued normal development is much reduced after an early brain insult (EBI) compared with TBI in a slightly older child or young adult patient. The advent of increasingly sophisticated non‐invasive imaging technology has allowed assessment of the influence and time course of brain pathology both early and late after TBI. This has generated greater confidence on the part of clinicians in forecasting outcomes for an injured patient. But our increased understanding has still not allowed development of therapeutic strategies that might ameliorate the effect of an injury. It is suggested that an improved integration of major clinical and scientific effort needs to be made to appreciate the import of multiple interactions between cells forming the neurovascular unit in order to improve any potential for post‐traumatic recovery after TBI in neonates and young children.
Two‐dimensional ionospheric flow pattern associated with auroral streamers
Authors: Shi Yong , Zesta Eftyhia , Lyons Larry R. , Yang J. , Boudouridis A. , Ge Y. S. , Ruohoniemi J. M. , Mende S.
Published: December 2011

We present direct two‐dimensional flow observations and auroral images from the Super Dual Auroral Radar Network (SuperDARN) radar and Wideband Imaging Camera onboard Imager for Magnetopause‐to‐Aurora Global Exploration (IMAGE/WIC) imager to investigate the ionospheric flow pattern associated with auroral streamers for four events. Using the SuperDARN observations allows us to observe the flow associated with the streamers in the context of the larger‐scale background convection. For all four cases studied, streamers developed from preexisting east‐west (EW) arcs that initiated from bead‐like or small‐scale auroral intensifications around the auroral poleward boundary. We find a vortex‐like flow pattern with clockwise sense surrounding both the initial auroral forms and the ensuing streamers. We also found in three cases signatures of flow bifurcations at the equatorward end of the streamers, which suggests a double vortex‐like flow pattern with the counterclockwise vortex east of the clockwise one. Our results are consistent with the double‐vortex flow structure that results from interchange convection associated with a plasma sheet bubble predicted by different numerical simulations. This supports several previous studies and offers more complete observational evidence that the observed flow pattern may be the ionospheric manifestation of interchange instability in the plasma sheet.
Imaging short‐period seismic radiation from the 27 February 2010 Chile (MW 8.8) earthquake by back‐projection of P, PP, and PKIKP waves
Authors: Koper Keith D. , Hutko Alexander R. , Lay Thorne , Sufri Oner
Published: December 2011

Teleseismic short‐period (0.5–5 s) P waves from the 27 February 2010 Chile earthquake (Mw 8.8) are back projected to the source region to image locations of coherent short‐period seismic wave radiation. Several receiver array configurations are analyzed using different P wave arrivals, including networks of stations in North America (P), Japan (PKIKP), and Europe (PP), as well as a global configuration of stations with a broad azimuthal distribution and longer‐period P waves (5–20 s). Coherent bursts of short‐period radiation from the source are concentrated below the Chilean coastline, along the downdip portion of the megathrust. The short‐period source region expands bilaterally, with significant irregularity in the radiation. Comparison with finite fault slip models inverted from longer‐period seismic waves indicates that the regions of large slip on the megathrust are located updip of the regions of short‐period radiation, a manifestation of frequency‐dependent seismic radiation, similar to observations for the great 2011 Tohoku earthquake (Mw 9.0). Back projection of synthetic P waves generated from the finite fault models demonstrates that if the short‐period energy had radiated with the same space‐time distribution as the long‐period energy, back‐projection analysis would image it in the correct location, updip. We conclude that back‐projection imaging of short‐period signals provides a distinct view of the seismic source that is missed by studies based only on long‐period seismic waves, geodetic data, and/or tsunami observations.
Ascent dynamics of large phreatomagmatic eruption clouds: The role of microphysics
Authors: Van Eaton A. R. , Herzog M. , Wilson C. J. N. , McGregor J.
Published: December 2011

We examine the impact of abundant surface water interaction on the development of volcanic clouds from large‐scale (>108 kg s−1 magma) phreatomagmatic eruptions, presenting the first 2‐D large‐eddy simulations of “wet” volcanic plumes that incorporate the effects of microphysics. The Active Tracer High‐Resolution Atmospheric Model was forced with field‐derived inputs from an exceptionally large phreatomagmatic eruption: the 27 ka Oruanui supereruption (Taupo volcano, New Zealand). Surface water contents were varied from 0 to 40 wt% for eruptions with equivalent magma eruption rates of ∼1.3 × 108 and 1.1 × 109 kg s−1. Our findings confirm that increased surface water has a pronounced impact on column stability, leading to transitional column behavior and hybrid clouds resulting from simultaneous ascent of material from stable columns and pyroclastic density currents (PDCs). Contrary to the suggestion of previous workers, however, abundant surface water does not systematically lower the spreading level or maximum height of volcanic clouds, owing to vigorous microphysics‐assisted lofting of PDCs. The simulated behavior and ash cloud dimensions provide a close match to field evidence from the Oruanui case study. Cloud heights from the collapsing eruption columns also show a notable sensitivity to changes in the altitude of the tropopause, while ambient humidity primarily impacts the abundance of airborne hydrometeors (particularly ice) associated with the volcanic clouds. General relationships between eruption style, meteorological conditions, and the resulting vertical profiles of volcanic emissions outlined here could also be adapted for use in operational volcanic ash forecasting and deposit reconstruction techniques already in existence.
Rain‐induced variability of near sea‐surface T and S from drifter data
Authors: Reverdin G. , Morisset S. , Boutin J. , Martin N.
Published: December 2011

The effect of rain on sea surface temperature, salinity and density is examined using data of surface drifters in regions of the tropical oceans with large rainfall. In a few off‐equatorial areas, there are sufficient drifter data to composite average daily cycles. There, the period of the day with largest salinity changes is associated with the largest rainfall rates and the lowest salinity. For a one‐yearlong trajectory in the southwest Pacific, this results in an early morning salinity minimum, whereas the opposite is found close to equatorial West Africa. We then consider individual freshening events larger than 0.1 psu (averaging 0.56 psu at 50 cm), and find that they are often related with local rainfall, are associated with a surface cooling, and relax in a time inversely proportional to wind intensity. The temperature cooling is dependent on the time of day, but the freshening presents less daily cycle and the largest fast changes in salinity tend to be associated with the largest rainfall rates. When two measurement levels are available, the initial salinity signal is larger by more than 20% at the shallow depth (15 cm) compared with the deeper measurement level (near 50 cm), and the temperature and salinity gradients between the two levels are proportional (0.22°C for a 1% dilution).
The roles of temperature and water vapor at different stages of the polar mesospheric cloud season
Authors: Rong P. P. , Russell J. M. , Hervig M. E. , Bailey S. M.
Published: December 2011

Temperature, or alternatively, saturation vapor pressure (PSAT), dominantly controls the polar mesospheric cloud (PMC) seasonal onset and termination, characterized by a strong anticorrelated relationship between the Solar Occultation for Ice Experiment (SOFIE)‐observed PMC frequency and PSAT on intraseasonal time scales. SOFIE is highly sensitive to weak clouds and can obtain a nearly full spectrum of PMCs. Both the SOFIE PMC frequency and PSAT indicate a rapid onset and termination of the season. Compared to PSAT, the water vapor partial pressure (PH2O) exhibits only a slight increase from before to after the start of the season. We are able to use the PSAT daily minimum and two averaged PH2O levels taken before and after the solstice, respectively, to estimate the start and end days of the PMC season within 1–2 days uncertainty. SOFIE ice mass density and its relationship to PH2O and PSAT are examined on intraseasonal scales and for two extreme conditions, i.e., strong and weak cloud cases. In the strong cloud case, such as those bright clouds that occur during the core of the season, PH2O far exceeds PSAT and dominantly controls the ice mass density variation, while in the weak cloud case, such as those clouds that occur at the start and end of the season, PH2O and PSAThave comparable magnitudes, vary in concert, and have similar effects on the ice mass density variation. These results suggest that the long‐term brightness trends reported by DeLand et al. (2007) are primarily driven by changes in water vapor (H2O), not temperature.
A method for physically based model analysis of conjunctive use in response to potential climate changes
Authors: Hanson R. T. , Flint L. E. , Flint A. L. , Dettinger M. D. , Faunt C. C. , Cayan Dan , Schmid Wolfgang
Published: December 2011

Potential climate change effects on aspects of conjunctive management of water resources can be evaluated by linking climate models with fully integrated groundwater–surface water models. The objective of this study is to develop a modeling system that links global climate models with regional hydrologic models, using the California Central Valley as a case study. The new method is a supply and demand modeling framework that can be used to simulate and analyze potential climate change and conjunctive use. Supply‐constrained and demand‐driven linkages in the water system in the Central Valley are represented with the linked climate models, precipitation‐runoff models, agricultural and native vegetation water use, and hydrologic flow models to demonstrate the feasibility of this method. Simulated precipitation and temperature were used from the GFDL‐A2 climate change scenario through the 21st century to drive a regional water balance mountain hydrologic watershed model (MHWM) for the surrounding watersheds in combination with a regional integrated hydrologic model of the Central Valley (CVHM). Application of this method demonstrates the potential transition from predominantly surface water to groundwater supply for agriculture with secondary effects that may limit this transition of conjunctive use. The particular scenario considered includes intermittent climatic droughts in the first half of the 21st century followed by severe persistent droughts in the second half of the 21st century. These climatic droughts do not yield a valley‐wide operational drought but do cause reduced surface water deliveries and increased groundwater abstractions that may cause additional land subsidence, reduced water for riparian habitat, or changes in flows at the Sacramento–San Joaquin River Delta. The method developed here can be used to explore conjunctive use adaptation options and hydrologic risk assessments in regional hydrologic systems throughout the world.
Wavelength tunable ultraviolet laser emission via intra-cavity frequency doubling of an AlGaInP vertical external-cavity surface-emitting laser down to 328 nm
Authors: Schwarzbäck T. , Kahle H. , Eichfelder M. , Roßbach R. , Jetter M. , Michler P.
Published: December 2011

We demonstrate an optically pumped vertical external-cavity surface-emitting laser in a compact v-shaped cavity configuration for frequency doubling to the ultraviolet (UV) spectral range at ∼330 nm. The fundamental red laser emission is realized with a metal-organic vapor-phase epitaxy grown (GaxIn1−x)0.5P0.5/[(AlxGa1−x)yIn1−y]0.5P0.5 multi-quantum-well structure. Second harmonic generation is accomplished by using a beta barium borate non-linear crystal to generate maximum UV output powers exceeding 100 mW. By using a birefringent filter, we are able to tune the fundamental laser resonance to realize a maximum tuning range of 7.5 nm of the second harmonic.
Three-dimensional evolution of flow structures in transitional circular and chevron jets
Authors: Violato Daniele , Scarano Fulvio
Published: December 2011

The three-dimensional behavior of flow transition in circular and 6-chevron jets at Re = 5000 is investigated with experiments conducted on a free water jet by time-resolved tomographic particle image velocimetry. The emphasis is on the unsteady organization of coherent flow structures, which play a role in the generation of acoustic noise. Shedding and pairing of vortices are the most pronounced phenomena observed in the near field of the circular jet. The first and second pairing amplify the axial pulsatile motion in the jet column and lead to the growth of azimuthal waves culminating in the breakup of the vortex ring. Streamwise vortices of axial and radial vorticity are observed in the outer region and move inward and outward under the effect of the vortex rings. In the jet with chevrons, the axisymmetric ring-like coherence of the circular jet is not encountered. Instead, streamwise flow structures of azimuthal vorticity emanate from the chevron apices, and counter-rotating streamwise vortices of axial and radial vorticity develop from the chevron notches. The decay of streamwise vortices is accompanied by the formation of C-shaped structures. The three-dimensional analysis allows quantifying the vortex stretching and tilting activity, which, for the circular jet exit, is related to the azimuthal instabilities and the streamwise vortices connecting the vortex rings. In the chevron jet, stretching and tilting peak during the formation of C-structures. Following Powell’s aeroacoustic analogy, the spatial distribution of the source term is mapped, evaluating the temporal derivative of the Lamb vector. The spatio-temporal evolution of such source term is visualized revealing that the events of highest activity are associated with the processes of vortex-ring pairing and vortex-ring disruption for the circular jet, and with the decay of streamwise instabilities and the formation of C-shaped structures for the chevron case.
Correlations and fluctuations of stress and velocity in suspensions of swimming microorganisms
Authors: Underhill Patrick T. , Graham Michael D.
Published: December 2011

Active systems, which are driven out of equilibrium, can produce long range correlations and large fluctuations that are not restricted by the fluctuation-dissipation theorem. We consider here the fluctuations and correlations in suspensions of swimming microorganisms that interact hydrodynamically. Modeling the organisms as force dipoles in Stokes flow and considering run-and-tumble and rotational diffusion models of their orientational dynamics allow derivation of closed form results for the stress fluctuations in the long-wave limit. Both of these models lead to Lorentzian distributions, in agreement with some experimental data. These fluctuations are not restricted by the fluctuation-dissipation theorem, as is explicitly verified by comparing the fluctuations with the viscosity of the suspension. In addition to the stress fluctuations in the suspension, we examine correlations between the organisms. Because of the hydrodynamic interactions, the velocities of two organisms are correlated even if the positions and orientations are uncorrelated. We develop a theory of the velocity correlations in this limit and compare with the results of computer simulations. We also formally include orientational correlations in the theory; and comparing with simulations, we are able to show that these are important even in the dilute limit and are responsible in large part for the velocity correlations. While the orientation correlations cannot as yet be predicted from this theory, by inserting the results from simulations into the theory it is possible to properly determine the form of the swimmer velocity correlations. These correlations of orientations are also the key to understanding the spatial correlations of the fluid velocity. Through simulations we show that the orientational correlations decay as r−2 with distance—inserting this dependence into the theory leads to a logarithmic dependence of the velocity fluctuations on the size of the system.
Thermal analysis of high intensity organic light-emitting diodes based on a transmission matrix approach
Authors: Qi Xiangfei , Forrest Stephen R.
Published: December 2011

We use a general transmission matrix formalism to determine the thermal response of organic light-emitting diodes (OLEDs) under high currents normally encountered in ultra-bright illumination conditions. This approach, based on Laplace transforms, facilitates the calculation of transient coupled heat transfer in a multi-layer composite characteristic of OLEDs. Model calculations are compared with experimental data on 5 cm × 5 cm green and red-emitting electrophosphorescent OLEDs under various current drive conditions. This model can be extended to study other complex optoelectronic structures under a wide variety of conditions that include heat removal via conduction, radiation, and convection. We apply the model to understand the effects of using high-thermal-conductivity substrates, and the transient thermal response under pulsed-current operation.
Pressure-driven capillary viscometer: Fundamental challenges in transient flow viscometry
Authors: Digilov Rafael M.
Published: December 2011

We describe an unsteady pressure-driven capillary viscometer, in which the liquid under test is forced through a capillary tube by compressed-air pressure. The principle of operation involves measurement of the driving pressure versus time that decays progressively as the fluid flows and covers continuously a broad shear rate range in a single measurement. The viscosity is determined by curve fitting of the experimental data to the explicit expression for the transient pressure as a function of time. A laboratory bench test shows the validity of the theoretical approach for viscosity determination of both Newtonian and non-Newtonian liquids.
Electrospinning: Distribution of charges in liquid jets
Authors: Kornev Konstantin G.
Published: December 2011

An analysis of the radial distribution of charges in liquid jets is presented. Two cases where considered: (1) when the charges are uniformly distributed through the jet cross-section but are allowed to concentrate at the jet surface with time; (2) when the charges reach a steady state where the Coulomb repulsion and Brownian mixing are counterbalanced keeping the charges inside the jet. Using the first model, we showed that the charge adsorption in nonpolar fluids occurs much faster than that in polar fluids. This provides the basis for the consideration of the second model applicable for polar liquids. We examined this case and found that a steady state does exist, but the concentration of charges is limited from above by a critical concentration inversely proportional to the square of the jet radius. It was shown that above this critical concentration, the charges should accumulate at the jet surface producing an infinitely large surface charge. Using this analysis, we suggest the classification of different regimes of electrospinning when the jets are mostly carrying the volume or surface charges.
The stability of the mesospheric plasma layer
Authors: Pandey B. P. , Vladimirov S. V.
Published: December 2011

The presence of micron and sub-micron size dust in the Earth’s summer mesopause are a possible cause of electron density depletion. Whereas electrons in this weakly ionized and weakly magnetized layer are frozen in the magnetic field, the ions and dust are highly diffusive. This relative drift between the plasma particles will cause a current in the medium. The presence of such a current can destabilize the plasma layer with a growth rate of the order of Alfvén frequency. Since required current density for the onset of this instability is on the order of J≳0.03A/m2, it is quite unlikely that such a strong current is present in the mesosphere. However, owing to the prevailing ambiguity of measurements, the existence of such a current is not completely ruled out.
Onset conditions for positive direct current corona discharges in air under the action of photoionization
Authors: Zheng Yuesheng , Zhang Bo , He Jinliang
Published: December 2011

This paper presents a numerical model for the inception of positive dc corona discharges in air near cylindrical anodes, which plays a bridge role between the classic positive corona onset criterion and the photoionization model considering the effective radiation wavelength. The predicted onset voltages agree well with Peek’s experimental data in a wide range of conductor radii and relative air densities. The influence of the collisional quenching of emitting excited states on the surface onset field is significant with low air density or small conductor radius. Within the effective radiation wavelength, numerical expressions for the photon absorption coefficient in air and Townsend’s second coefficient due to photoionization are deduced on the basis of the new model. A different perspective on the classic coefficients is given.
Tuning the surface magnetism of γ-Fe2O3 nanoparticles with a Cu shell
Authors: Desautels R. D. , Skoropata E. , Chen Y.-Y. , Ouyang H. , Freeland J. W. , van Lierop J.
Published: December 2011

An interfacial monolayer of CuO in Cu-coated γ-Fe2O3 nanoparticles enables significantly decreased intrinsic surface spin disorder compared to bare γ-Fe2O3 nanoparticles. Element specific x-ray absorption spectroscopy at the L-edges for Cu and Fe indicates that the magnetic moment of the CuO in the shell interacts with the γ-Fe2O3 nanoparticle’s surface magnetic moments. This exchange interaction cants the moments of the CuO resulting in a non-zero Cu moment, altering the γ-Fe2O3 nanomagnetism.
Reducing operation current of Ni-doped silicon oxide resistance random access memory by supercritical CO2 fluid treatment
Authors: Chang Kuan-Chang , Tsai Tsung-Ming , Chang Ting-Chang , Syu Yong-En , Wang Chia-C. , Chuang Siang-Lan , Li Cheng-Hua , Gan Der-Shin , Sze Simon M.
Published: December 2011

In the study, we reduced the operation current of resistance random access memory (RRAM) by supercritical CO2 (SCCO2) fluids treatment. The power consumption and joule heating degradation of RRAM device can be improved greatly by SCCO2 treatment. The defect of nickel-doped silicon oxide (Ni:SiOx) was passivated effectively by the supercritical fluid technology. The current conduction of high resistant state in post-treated Ni:SiOx film was transferred to Schottky emission from Frenkel-Pool due to the passivation effect. Additionally, we can demonstrate the passivation mechanism of SCCO2 for Ni:SiOx by material analyses of x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.
Characterization and mechanism of He plasma pretreatment of nanoscale polymer masks for improved pattern transfer fidelity
Authors: Weilnboeck F. , Metzler D. , Kumar N. , Oehrlein G. S. , Bruce R. L. , Engelmann S. , Fuller N.
Published: December 2011

Roughening of nanoscale polymer masks during plasma etching (PE) limits feature critical dimensions in current and future lithographic technologies. Roughness formation of 193 nm photoresist (PR) is mechanistically explained by plasma-induced changes in mechanical properties introduced at the PR surface (∼2 nm) by ions and in parallel in the material bulk (∼200 nm) by ultraviolet (UV) plasma radiation. Synergistic roughening of polymer masks can be prevented by pretreating PR patterns with a high dose of He plasma UV exposure to saturate bulk material modifications. During subsequent PE, PR patterns are stabilized and exhibit improved etch resistance and reduced surface/line-edge roughness.
Coherence in a transmon qubit with epitaxial tunnel junctions
Authors: Weides Martin P. , Kline Jeffrey S. , Vissers Michael R. , Sandberg Martin O. , Wisbey David S. , Johnson Blake R. , Ohki Thomas A. , Pappas David P.
Published: December 2011

We developed transmon qubits based on epitaxial tunnel junctions and interdigitated capacitors. This multileveled qubit, patterned by use of all-optical lithography, is a step towards scalable qubits with a high integration density. The relaxation time T1 is 0.72−0.86 μs and the ensemble dephasing time T2* is slightly larger than T1. The dephasing time T2 (1.36 μs) is nearly energy-relaxation-limited. Qubit spectroscopy yields weaker level splitting than observed in qubits with amorphous barriers in equivalent-size junctions. The qubit’s inferred microwave loss closely matches the weighted losses of the individual elements (junction, wiring dielectric, and interdigitated capacitor), determined by independent resonator measurements.
Trap-state whispering-gallery mode lasing from high-quality tin-doped CdS whiskers
Authors: Liu R. B. , Zhuang X. J. , Xu J. Y. , Li D. B. , Zhang Q. L. , Ding K. , He P. B. , Ning C. Z. , Zou B. S. , Pan A. L.
Published: December 2011

High-quality surface tin-doped hexagonal CdS whiskers were synthesized by a well-controlled in situ source exchange chemical vapor deposition route. Under local light excitation, the detected microphotoluminescence from any positions along the length of these whiskers exhibits strong and multi-mode trap-state whispering-gallery (WG) mode emission. With elevating the pumping power, some of these WG modes start lasing at an ultra-low threshold, with lasing wavelength covering a broad range from ∼540 to ∼750 nm. Calculations using a plane-wave model of WG modes show that all these trap-state lasing modes are transverse magnetic polarized, which was well explained by a two-dimensional finite element simulation. The surface doped semiconductor structures have potential applications as low-threshold tunable micro/nanoscale lasers in optical storage, lighting, and optical communications.
Fundamental limits in the external quantum efficiency of single nanowire solar cells
Authors: Heiss Martin , Fontcuberta i Morral Anna
Published: December 2011

The fundamental limits for the measurement of the efficiency of single nanowire solar cell devices are presented. We evaluate the effect of the substrate, light polarization, and existence of Mie resonances in the absorption of the solar spectrum for nanowires with diameters from 10 to 300 nm. We find that the efficiency measured under such configuration can be underestimated between a factor 1.6 and 7.0 for GaAs nanowires and between 6.7 and 15.9 for silicon nanowires. These results constitute a reference for understanding the limits in the measurement of single nanowire devices.
Magnetic properties of Fe chains on Cu2N/Cu(100): A density functional theory study
Authors: Nicklas Jeremy W. , Wadehra Amita , Wilkins John W.
Published: December 2011

We present a density functional study of the magnetic properties of Fe adatoms on Cu2N/Cu(100) surface. The magnetic anisotropy energies of a single Fe atom are in excellent agreement with the available experiments. Our results for the spin densities and exchange coupling strengths for Fe dimer and trimer establish antiferromagnetic configuration to be the ground state due to predominant superexchange interaction mediated by nitrogen atoms in this system.
Infrared surface plasmons on heavily doped silicon
Authors: Shahzad Monas , Medhi Gautam , Peale Robert E. , Buchwald Walter R. , Cleary Justin W. , Soref Richard , Boreman Glenn D. , Edwards Oliver
Published: December 2011

Conductors with infrared plasma frequencies are potentially useful hosts of surface plasmon polaritons (SPP) with sub-wavelength mode confinement for sensing applications. A challenge is to identify such a conductor that also has sharp SPP excitation resonances and the capability to be functionalized for biosensor applications. In this paper we present experimental and theoretical investigations of IR SPPs on doped silicon and their excitation resonances on doped-silicon gratings. The measured complex permittivity spectra for p-type silicon with carrier concentration 6×1019 and 1×1020 cm−3 show that these materials should support SPPs beyond 11 and 6 μm wavelengths, respectively. The permittivity spectra were used to calculate SPP mode heights above the silicon surface and SPP propagation lengths. Reasonable merit criteria applied to these quantities suggest that only the heaviest doped material has sensor potential, and then mainly within the wavelength range 6 to 10 μm. Photon-to-plasmon coupling resonances, a necessary condition for sensing, were demonstrated near 10 μm wavelength for this material. The shape and position of these resonances agree well with simple analytic calculations based on the theory of Hessel and Oliner (1965).
Enhancement of the photoelectrochemical properties of Cl-doped ZnO nanowires by tuning their coaxial doping profile
Authors: Fan Jiandong , Güell Frank , Fábrega Cristian , Shavel Alexey , Carrete Alex , Andreu Teresa , Ramón Morante Joan , Cabot Andreu
Published: December 2011

Arrays of vertically aligned ZnO:Cl/ZnO core-shell nanowires were used to demonstrate that the control of the coaxial doping profile in homojunction nanostructures can improve their surface charge carrier transfer while conserving potentially excellent transport properties. It is experimentally shown that the presence of a ZnO shell enhances the photoelectrochemical properties of ZnO:Cl nanowires up to a factor 5. Likewise, the ZnO shell promotes the visible photoluminescence band in highly conducting ZnO:Cl nanowires. These lines of evidence are associated with the increase of the nanowires’ surface depletion layer.
Note: Accurate ab initio predictions of ionization energies of propargyl and allyl radicals: Revisited
Authors: Lau Kai-Chung , Ng C. Y.
Published: December 2011

We have reexamined the ionization energies (IEs) of propargyl (CH2CCH) and allyl (CH2CHCH2) radicals using the CCSDTQ(full)/ complete basis set method. Both IE predictions, IE(CH2CCH) = 8.706 eV and IE(CH2CHCH2) = 8.144 eV, are found to compare favorably with the most recent experimental IE values of 8.6982 ± 0.0005 eV for propargyl radical and 8.1314 ± 0.0003 and 8.1309 ± 0.0003 eV for allyl radical determined by rotationally resolved photoelectron measurements.
Exploring Soy-Derived Alternatives to Fish Meal: Using Soy Protein Concentrate and Soy Protein Isolate in Hybrid Striped Bass Feeds
Authors: Blaufuss Patrick , Trushenski Jesse
Published: December 2011

Many protein sources, including soybean meal (SBM), have been investigated as alternatives to fish meal (FM) in aquaculture feeds. However, FM replacement in feeds for carnivorous fishes is limited by problems with feed intake, growth rate, and overall health associated with the reduced digestibility of SBM and the antinutritional factors (ANFs) it contains. Processing strategies can reduce the effects of ANFs and can improve protein utilization. We conducted two trials to examine the possibility of further FM replacement in SBM-maximized feeds for hybrid striped bass (white bass Morone chrysops × striped bass M. saxatilis) by using two refined soy products: soy protein concentrate (SPC) and soy protein isolate (SPI). Diets were formulated to maximize FM replacement, beginning with a basal diet containing 10% FM and 65% SBM. Further reductions in FM were made by using SPC or SPI to spare FM-derived protein. Refined soy protein-based feeds were evaluated in feeding trials with juvenile hybrid striped bass that were cultured in recirculating aquaculture systems. Although reducing dietary FM below 10% by using SPC or SPI resulted in decreased production performance, this appears to be due to a reduction in palatability rather than to negative biological effects (e.g., changes in gut histology, major shifts in carcass proximate composition) associated with ANFs or other dietary effects. A moderate reduction in growth associated with administering the SPC-based feeds corresponded with a moderate reduction in feed intake, whereas dietary inclusion of SPI resulted in severe feeding reluctance, starvation, and cannibalism. Although SPC and SPI may vary in their suitability as FM alternatives, the differential performance observed may also be related to the fact that younger, smaller fish were used in the SPI trial than in the SPC trial. Refined soy proteins can be used in conjunction with SBM to spare FM, but the cost of these products and their acceptability to juvenile carnivorous fish will determine the extent of their utilization in aquafeeds.
ZBTB1 is a determinant of lymphoid development
Authors: Siggs Owen M. , Li Xiaohong , Xia Yu , Beutler Bruce
Published: December 2011

In this study, we describe a chemically induced mouse mutation that caused a complete and cell-intrinsic T cell deficiency. Development of other lymphoid lineages was also partially impaired and was severely compromised under competitive conditions. Positional cloning, retroviral transduction, and a somatic reversion event revealed that the causative mutation lay within Zbtb1 (zinc finger and BTB domain containing 1), a gene conserved throughout vertebrate evolution. Our data establish ZBTB1 as a critical determinant of T cell development and lymphopoiesis in general, most likely by acting as a transcriptional regulator.
The structure of free automorphic Moufang loops
Authors: Grishkov A. , Plaumann P. , Sabinina L.
Published: December 2011

We describe the structure of a free loop of rank

n
n

in the variety of automorphic Moufang loops as a subdirect product of a free group and a free commutative Moufang loop, both of rank

n
n

. In particular, the variety of automorphic Moufang loops is the join of the variety of groups and the variety of commutative Moufang loops.
Errata to “The defect of Fano 3-folds”
Authors: Kaloghiros Anne-Sophie
Published: December 2011

This note corrects three minor errors in The defect of Fano

3
3

-folds [J. Algebraic Geom. 20 (2011), 127–149] kindly pointed out by Professor Yuri Prokhorov and by Dr. Mark Haskins.
A Step Ahead: Running Injuries and Illness
Authors: Thing James
Published: December 2011

Running has become a popular pastime in the UK over the last 30 years with the evolution of large city marathons, as well as charity and fun runs making endurance exercise a realistic and achievable target. This has led to the phenomenon whereby inexperienced runners may undertake physical activity that they are not fully prepared for, resulting in increased morbidity. Musculoskeletal problems form up to 15–20% of all general practice consultations with a significant proportion attributable to running. The scope of this article is to highlight common lower limb musculoskeletal injuries and running-related illnesses, focusing on basic diagnostic and management strategies within primary care.
II. DEVELOPMENT OF ADOPTED CHILDREN WITH HISTORIES OF EARLY ADVERSITY
Authors: Juffer Femmie , Palacios Jesús , Le Mare Lucy , Sonuga‐Barke Edmund J. S. , Tieman Wendy , Bakermans‐Kranenburg Marian J. , Vorria Panayiota , van IJzendoorn Marinus H. , Verhulst Frank C.
Published: December 2011

This chapter first presents a review of research on the development of adopted children, focusing on meta‐analytic evidence and highlighting comparisons between adopted children with and without histories of early adversity. Some methodological issues arising from this literature are considered as well. Second, 7 longitudinal studies of adopted children's development are described, and the convergence of findings across the longitudinal studies and with the cross‐sectionally based meta‐analytic evidence is discussed. Third, the role of the adoptive family in supporting adopted children's development is explored.
IV. GROWTH FAILURE IN INSTITUTIONALIZED CHILDREN
Authors: Johnson Dana E. , Gunnar Megan R.
Published: December 2011

Children within institutional care settings experience significant global growth suppression, which is more profound in children with a higher baseline risk of growth impairment (e.g., low birth weight [LBW] infants and children exposed to alcohol in utero). Nutritional insufficiencies as well as suppression of the growth hormone–insulin‐like growth factor axis (GH‐IGF‐1) caused by social deprivation likely both contribute to the etiology of psychosocial growth failure within these settings. Their relative importance and the consequent clinical presentations probably relate to the age of the child. While catch‐up growth in height and weight are rapid when children are placed in a more nurturing environment, many factors, particularly early progression through puberty, compromise final height. Potential for growth recovery is greatest in younger children and within more nurturing environments where catch‐up in height and weight is positively correlated with caregiver sensitivity and positive regard. Growth recovery has wider implications for child well‐being than size alone, because catch‐up in height is a positive predictor of cognitive recovery as well. Even with growth recovery, persistent abnormalities of the hypothalamic‐pituitary‐adrenal system or the exacerbation of micronutrient deficiencies associated with robust catch‐up growth during critical periods of development could potentially influence or be responsible for the cognitive, behavioral, and emotional sequelae of early childhood deprivation. Findings in growth‐restricted infants and those children with psychosocial growth are similar, suggesting that children experiencing growth restriction within institutional settings may also share the risk of developing the metabolic syndrome in adulthood (obesity, Type 2 diabetes mellitus, hypertension, heart disease). Psychosocial deprivation within any caregiving environment during early life must be viewed with as much concern as any severely debilitating childhood disease.
VI. SENSITIVE PERIODS
Authors: Zeanah Charles H. , Gunnar Megan R. , McCall Robert B. , Kreppner Jana M. , Fox Nathan A.
Published: December 2011

This chapter reviews sensitive periods in human brain development based on the literature on children raised in institutions. Sensitive experiences occur when experiences are uniquely influential for the development of neural circuitry. Because in humans, we make inferences about sensitive periods from evaluations of complex behaviors, we underestimate the occurrence of sensitive periods at the level of neural circuitry. Although we are most interested in complex behaviors, such as IQ or attachment or externalizing problems, many different sensitive periods at the level of circuits probably underlie these complex behaviors. Results from a number of studies suggest that across most, but not all, domains of development, institutional rearing limited to the first 4–6 months of life is associated with no significant increase risk for long‐term adverse effects relative to noninstitutionalized children. Beyond that, evidence for sensitive periods is less compelling, meaning that “the earlier the better” rule for enhanced caregiving is a reasonable conclusion at the current state of the science.
VIII. THE SITUATION FOR CHILDREN WITHOUT PARENTAL CARE AND STRATEGIES FOR POLICY CHANGE
Authors: Engle Patrice L. , Groza Victor K. , Groark Christina J. , Greenberg Aaron , Bunkers Kelley McCreery , Muhamedrahimov Rifkat J.
Published: December 2011

Research that clearly demonstrates the negative effects of institutionalization, particularly for young children, has been critical for changing policy. However, actually putting science into action requires advocacy, persistence, and perseverance. Policy makers and advocates must be informed about the research and use it effectively. This paper proposes a number of key components for translating research into policy and programs: analyzing the situation, using evidence to build the case for action, developing policies, building program capacity in child welfare and early childhood development, creating a family‐based child welfare system, and developing a system of monitoring and accountability. Much of the knowledge in this paper comes from experiences, desk reviews, and case studies of successful practices. Research provides the basis, but moving research to practice depends on collaboration between researchers who understand the key policy perspectives and policy makers who understand the research.
Collaboration by Deflection: Coping with Spent Nuclear Fuel
Authors: Karlesky Joseph J.
Published: December 2011

For more than three decades, the U.S. national government has wrestled with the problem of siting a central repository for high‐level radioactive waste, most of it spent fuel from nuclear power plants. Scholars and practitioners recommend a collaborative and participative approach to the siting process to ensure accountability and representativeness, but the search for a working repository so far has been unsuccessful. Consequently, more nuclear power plants must add or expand dry cask facilities to store accumulating amounts of spent fuel. Are collaboration and accountability and successful execution of results possible in state decisions on dry cask storage in a way that they have eluded the central siting process? The special characteristics of dispersed dry cask storage, in contrast to transporting the waste to a central repository, can facilitate collaboration and accountability, as decisions on dry cask storage in Minnesota and Vermont demonstrate.
Intercountry Adoption Flows from Africa to the U.S.: A Fifth Wave of Intercountry Adoptions?
Authors: Davis Mary Ann
Published: December 2011

This article addresses whether there is the beginning of a fifth wave of intercountry adoptions (ICAs) from Africa to the United States (U.S.). ICAs function as a “quiet migration” of children [Weil (1984) International Migration Review 18(2):276–293; Lovelock (2000) International Migration Review 34 (3):907–949; Selman (2002) Population Research and Policy Review 21:205–225]. U.S. Department of Justice Immigration and Naturalization Service (INS) data from 1971 to 2009 indicate that there were 421,085 ICAs to the U.S. Tarmann (2003:2, http://www.prb.org/Articles/2003/InternationalAdoptionRateinUSDoubledinthel990s.aspx?p=1 ) reported that in 2000, U.S. parents completed one ICA for every 200 births. In the past, top sending countries have followed flows from Europe, South America, and Asia. INS data are used to analyze the increase in the intercountry adoptees from Africa from 1996 to 2009. Similar Hague Convention data are used for the comparison of the number of ICAs from Africa to other top recipient nations. Demographic and economic data are used to support the suggestion that ICAs, similar to other migratory flows, are from developing to developed countries.
The Impact of Migrant Remittances on School Attendance and Education Attainment: Evidence from Jordan
Authors: Mansour Wael , Chaaban Jad , Litchfield Julie
Published: December 2011

This paper evaluates the impact of migrant remittances on human capital accumulation among youth. An augmented human capital model with two outcomes, education attendance and education attainment, is estimated using a large nationally representative household survey from Jordan. Empirical results show that migrant remittance receipt has a positive effect on education attendance. This finding is obtained while controlling for other socio-economic determinants of schooling behavior and is robust to censorship and endogeneity bias. The results also indicate that the magnitude of the remittance impact on both education outcomes is larger for men compared with that of women.
Religion and Migration around the Globe: Introducing the Global Religion and Migration Database
Authors: Connor Phillip , Tucker Catherine
Published: December 2011

International migration is a global phenomenon involving nearly 215 million people, equivalent to 3% of the world's population. Previous databases of global migration catalog international migration using a variety of variables (sex, education, age); however, religion is rarely addressed within these data sets. Representing nearly half a million data points, the Global Religion and Migration Database (GRMD) was constructed – the only global database estimating the global migrant population (stock) by origin, destination, and religious affiliation. This research note serves as an introduction to the GRMD, detailing the construction of the database and providing key findings from a global perspective.
Maturation is associated with changes in rat cerebral artery structure, biomechanical properties and tone
Authors: Mandalà M. , Pedatella A. L. , Morales Palomares S. , Cipolla M. J. , Osol G.
Published: December 2011

Aim:

This study evaluated the hypothesis that physiological maturation affects cerebral artery smooth muscle–endothelial interactions involved in pressure‐induced tone and alters the dimensional and biomechanical properties of small posterior cerebral arteries (PCA).

Methods:

Secondary branches of PCA from young (4–5 weeks old, n = 11), adult (14–16 weeks old, n = 11) and mature (44–47 weeks old, n = 11) male Sprague‐Dawley rats were isolated, cannulated, pressurized and subjected to a range of intraluminal pressures (10–110 mmHg) to determine tone with and without pharmacologic nitric oxide synthase (NOS) inhibition. Measurements of passive lumen diameter and wall thickness as a function of pressure were used to determine changes in structure, distensibility and wall stress; histological analysis was performed on vessel cross‐sections to assess collagen and elastin contents.

Results:

Although pressure‐dependent tone decreased significantly during ageing, differences between groups were abolished by NOS inhibition. Vessel diameters increased in adult vs. young rats (at 90 mmHg, 233 ± 6.0 μm vs. 192 ± 4.5 μm; P < 0.05), possibly secondary to somatic growth. Further ageing was associated with reductions in lumen diameter (207 ± 6.5 μm; P < 0.05), increased wall and media thickness (and wall/lumen ratio) and cross‐sectional area. Distensibility and wall collagen were unchanged, although elastin content was significantly reduced.

Conclusions:

Maturation is associated with differences in PCA dimensional properties that indicate a pattern of initial outward eutrophic, followed by inward hypertrophic remodelling. Functionally, the contribution of basal NO increases with age in a way that reduces pressure‐dependent tone and diminishes vasodilator reserve.