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We have assembled a new sample of some of the most FIR-luminous galaxies in the Universe and have imaged them in 1.1 mm dust emission and measured their redshifts 1 < z < 4 via CO emission lines using the 32-m Large Millimeter Telescope / Gran Telescopio Milimétrico (LMT/GTM). Our sample of 31 submm galaxies (SMGs), culled from the Planck and Herschel all-sky surveys, includes 14 of the 21 most luminous galaxies known, with LFIR > 1014L⊙ and SFR > 104M⊙/yr. These extreme inferred luminosities – and multiple / extended 1.1 mm images – imply that most or all are strongly gravitationally lensed, with typical magnification μ ~ 10 × . The gravitational lensing provides two significant benefits: (1) it boosts the S/N, and (2) it allows investigation of star formation and gas processes on sub-kpc scales.
A number of applications call for the organization of resistive non-volatile memory (NVM) into large, densely-packed crossbar arrays. While resistive-NVM devices often possess some degree of inherent nonlinearity (typically 3-30× contrast), the operation of large (>1000×1000 device) arrays at low power tends to require large (> 1e7) ON-to-OFF ratios between the currents passed at high and at low voltages. Such large nonlinearities can be implemented by including a distinct access device together with each of the state-bearing resistive-NVM elements. While such an access device need not store data, its list of requirements is almost as challenging as the specifications demanded of the memory device.
We review our work on high-performance access devices based on Cu-containing Mixed-Ionic-Electronic Conduction (MIEC) materials [1–7]. (This version focuses only on the MIEC-based access device itself; previously-published longer versions of this work [8–10] also include more extensive surveys of competing devices as well.) These devices require only the low processing temperatures of the Back-End-Of-the-Line (BEOL), making them highly suitable for implementing multi-layer crossbar arrays. MIEC-based access devices offer large ON/OFF ratios (>1e7), a significant voltage margin Vm (over which current < 10nA), and ultra-low leakage (<10pA), while also offering the high current densities needed for PCM and the fully bipolar operation needed for high-performance RRAM. Scalability to critical dimensions (CD) <30nm and thicknesses <15nm, tight distributions and 100% yield in large (512kBit) arrays, long-term stability of the ultra-low leakage states, and sub-50ns turn-ON times have all been demonstrated. Numerical modeling of these MIEC-based access devices shows that their operation depends on Cu+ mediated hole conduction. Circuit simulations reveal that while scaled MIEC devices are suitable for large crossbar arrays of resistive-NVM devices with low (<1.2V) switching voltages, a compact vertical stack of two MIEC devices in series could support large crossbar arrays for switching voltages up to 2.5V.
Memecylon wayanadense Ratheesh, Sivu & Pradeep, a new species of Melastomataceae from the Wayanad forests of Kerala, India, is described and illustrated. The new species is allied to Memecylon angustifolium, M. rivulare and M. sivadasanii but differs in habit, leaf shape, sclereid type, inflorescence type and position, and the shape and size of the sepals and petals. An UPGMA analysis of 20 RAPD primers resulted in two major clusters with Memecylon sivadasanii in one cluster and M. rivulare, M. angustifolium and M. wayanadense in the second cluster. Memecylon wayanadense forms a subgroup within the second cluster.
Polymeric materials are widely used in power generation and energy storage applications. Deoxyribonucleic acid (DNA) biopolymer-based hybrids have been found to display interesting electrical characteristics, such as a relatively high dielectric constant, good resistivity and dielectric breakdown behavior, and are promising as insulating dielectrics for capacitor applications. This research describes the processing, test structure design, and electrical characterization of DNA-sol-gel hybrids for energy storage applications.
This study aims to assess current practices of Canadian physicians providing botulinum toxin-A (BoNT-A) treatments for children with hypertonia and to contrast these with international “best practice” recommendations, in order to identify practice variability and opportunities for knowledge translation.
Thirteen Canadian physicians assembled to develop and analyze results of a cross-sectional electronic survey, sent to 50 physicians across Canada.
Seventy-eight percent (39/50) of physicians completed the survey. The most frequently identified assessment tools were Gross Motor Function Classification System, Modified Tardieu Scale and neurological examination. Goal-setting tools were infrequently utilized. Common indications for BoNT-A injections and the muscles injected were identified. Significant variability was identified in using BoNT-A for hip displacement associated with hypertonia. The most frequent adverse event reported was localized weakness; 54% reporting this “occasionally“ and 15% “frequently”. Generalized weakness, fatigue, ptosis, diplopia, dysphagia, aspiration, respiratory distress, dysphonia and urinary incontinence were reported rarely or never. For dosage, 52% identified 16 Units/kg body weight of Botox® as maximum. A majority (64%) reported a maximum 400 Units for injection at one time. For localization, electrical stimulation and ultrasound were used infrequently (38% and 19% respectively). Distraction was the most frequently used pain-management technique (64%).
Canadian physicians generally adhere to international best practices when using BoNT-A to treat paediatric hypertonia. Two knowledge-translation opportunities were identified: use of individualized goal setting prior to BoNT-A and enhancing localization techniques. Physicians reported a good safety profile of BoNT-A in children.
The potential of bio-dielectrics for thin film transistor applications was explored via the incorporation of titanium dioxide (TiO2) nanoparticles, rutile form, a high dielectric constant (ε) ceramic, in the deoxyribonucleic acid (DNA) bio-polymer. The DNA-ceramic hybrid films were fabricated from stable suspensions of the TiO2 nanoparticles in viscous, aqueous DNA solutions. Dielectric characterization revealed that the incorporation of TiO2 in DNA resulted in enhanced dielectric constant (14.3 at 1 kHz for 40 wt % TiO2) relative to that of DNA in the entire frequency range of 1 kHz-1 MHz. Variable temperature dielectric measurements, in the 20-80°C range, of the DNA-TiO2 films revealed that the ceramic additive stabilizes DNA against large temperature dependent variations in both ε and the dielectric loss factor tan δ. The bulk resistivity of the DNA-TiO2 hybrid films was measured to be two to three orders of magnitude higher than that of the control DNA films, indicating their potential for utilization as insulating dielectrics in transistor and capacitor applications.
Studies in adults with multiple sclerosis (MS) have associated regional brain abnormalities with memory impairment. While memory problems in children with MS are often reported, little is known about the neural correlates that may contribute to these difficulties. We measured verbal and nonverbal memory using the Test of Memory and Learning (TOMAL-2) in 32 children and adolescents with MS and 26 age- and sex-matched healthy controls. Memory performance was correlated with volumetric measures of the whole brain, hippocampus, amygdala, and thalamus. Brain volumes were normalized for age and sex using magnetic resonance imaging (MRI) data from the National Institutes of Health MRI Study of Normal Brain development. With the exception of story recall, performance on memory tests was similar to that of the control group. Relative to controls, patient with MS showed reduced volume in the whole brain (p < .001), amygdala (p < .005), and thalamus (p < .001), but not the hippocampus. In the patient group, word-list learning correlated with whole brain volume (r = .53) and hippocampal volume (r = .43), whereas visual recognition memory correlated with thalamic volume (r = .48). Findings are consistent with the well-established role of the hippocampus in learning and consolidation and also highlight the importance of diffuse brain pathology on memory function. (JINS, 2012, 18, 471–480)
Physical properties of multiple-energy B-ion implanted C60 thin films were investigated for various doses. Fourier Transform Infra-red Spectroscopy (FTIR) results indicate the structural transformation of C60 to amorphous carbon phase during implantation. The conductivity type of the implanted films is found to be p-type and the conductivity measurements reveal a dramatic increase in the conductivity with ion implantation. Temperature dependent conductivity shows the semiconducting nature of the B-ion implanted films. The optical absorption coefficient and optical gap of the implanted films have been observed as a function of B-ion dose. Measurements on implanted films subjected to thermal annealing indicate the removal of the defects caused during the implantation. Ion implantation-induced defects are found to partially annihilate with the annealing temperature. Electrical conductivity and optical gap are determined in the post-implanted films. The observation of the systematic increase in the conductivity of the annealed films is due to the removal of the defects and the formation of defect free boron impurity acceptor.
A systematic study has been made of the influence of the deposition conditions on the properties of SiO2 grown by liquid phase deposition (LPD), and a-Si:H manufactured by plasma enhanced chemical vapour deposition (PECVD) with the novel facility of source-gas heating. It is demonstrated that LPD-SiO2 can be grown at 50°C with good dielectric properties. Material has been produced with a resistivity of 1015 &cm and a dielectric strength of 9 MVcm-1.The oxide was found to have a negative fixed oxide charge of 4 × 1011 cm−2, with a dielectric constant of 3.08 and a refractive index of 1.44. In the case of a-Si:H, pre-heating the source gases has enabled material to be grown at 125°C with a hydrogen content of ∼ 10 at%, with a predominance of monohydride bonding and a photosensitivity of ∼ 104. Inverted-staggered thin film transistors have been fabricated incorporating these films with an On/Off ratio of five orders of magnitude, a sub-threshold slope of 1.3 Vdecade−1 and a field effect mobility of 0.20 cm2V−1s−1
In this work, the adhesion of CVD dielectric caps to ULK MSQ spin-on
dielectric materials with k values of 2.2 and 2.0, and a ULK CVD material
with a k value of 2.7 is presented. A substantial improvement in cap
adhesion to both the k2.2 ULK MSQ and the k2.7 ULK CVD material is
demonstrated. The improvement is obtained using a low-k CVD glue material
between the ULK dielectric and the subsequent cap material and/or by
optimizing the CVD cap film deposition. Four-point bend measurement of
adhesion strength is used to quantify the improvement in interface adhesion.
The improvement in CVD cap adhesion is demonstrated to be strongly dependent
upon both the glue layer film and the cap deposition conditions. While
optimization of the CVD cap materials results in adequate adhesion for the
k2.2 ULK MSQ, these improvements are demonstrated not to extend to the k2.0
ULK MSQ film.
Nuclear magnetic resonance (NMR) spin lattice relaxation is highly sensitive to the nature, amount, and homogeneity of unpaired-electron-containing impurities in silicon carbide and similar solids, and is a promising tool for the study of dopants and impurities. In nitrogen-doped 6H silicon carbide, 13C and 29Si NMR spin lattice relaxation is highly site-dependent. Not only do carbon sites relax much more rapidly than the corresponding silicon sites, but also there are unprecedented differences in relaxation efficiency among the different carbon (and silicon) sites, consistent with much higher unpaired electron density at the higher-symmetry (Types A and B) sites than at the lowest-symmetry (Type C) site. In contrast, all sites relax at equivalent rates in undoped samples and in commercial abrasive grade material with high levels of impurities, although there are large differences in relaxation efficiency among samples. The change in the nature of the relaxation process, from exponential in high-purity to stretched exponential in lower-purity samples, is apparently related to changes in unpaired-electron mobility.
Metal-polymer bilayers and multilayers are being increasingly used in the microelectronics industry. In many cases, the reliability of the device or the package is determined by the mechanical behavior of these composite layers. Finite element analyses are being widely used to model these systems. An accurate experimental understanding of the mechanical behavior of these systems would further enhance the usefulness of such analyses. The present study focuses on the mechanical behavior of composite bilayers consisting of polyimide and sputtered Ti and Ti alloy thin films. Tensile tests and stretch-deformation tests have been performed on bilayers consisting of a polyimide substrate sputter-coated individually with a 50 nm and a 500 nm Ti layer, a 500 nm Ti-Cu layer, and a 500 nm Ti-Ni layer. Tensile moduli, stresses for 0.2%, 2% and 15% offset strains, and strains to failure have been obtained and compared. These values are discussed with reference to the known mechanical properties of the individual layers in the composite material.
Multispeckle x-ray photon correlation spectroscopy measurements, carried out at beamline 8-ID at the Advanced Photon Source at Argonne National Laboratory, of opaque suspensions of silica nanoparticles in water and lutidine-water binary mixtures are presented.
Investigations of a high resolution X-ray emission spectrum in the range 0.66–0.75 nm obtained by irradiating a Germanium target with high-power p-polarized, 40 picosecond laser radiation at 532 nm wavelength was done. Spectra in the wavelength region of 2l-4l′ and 2l-5l′ L-shell transitions in F-like, Ne-like and Na-like germanium ions were recorded using the FSSR-2D spectrometer equipped with a spherically bent quartz crystal with a spectral resolution λ/Δλ better than 5000. Spectral lines were compared with theoretical values obtained using the LANL plasma kinetic code ATOMIC. Fair agreement between experimental and theoretical spectral lines has been observed, which allowed to measure enough high bulk electron temperature values of 560 eV and electron density of ∼1021 cm−3 in Ge plasma irradiated by rather small commercial high repetition rate Nd:YAG laser system.
This paper reports the development and validation of a disease-specific measure of health status and well-being of children with severe cerebral palsy (CP). The Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) was constructed from recommendations from caregivers, healthcare providers, and review of other measures. Items spanning six domains are rated on an ordinal scale. Standardized scores (0–100) are reported for each domain and in total. Primary caregivers (n=77) of 45 males and 32 females between 5 and 18 years of age (mean age 13y 5mo [SD 3y 4mo]) with CP, categorized by the Gross Motor Function Classification System (GMFCS) level, completed the CPCHILD. Caregivers of children with severe CP (GMFCS Levels IV and V) also completed a second administration of the CPCHILD 2 weeks after the first. The mean CPCHILD score for children with severe CP was 56.2 (SD 15.7; range 24–93). The mean CPCHILD scores for children in GMFCS Levels I to V were 22.0, 38.2, 23.0, 44.5, and 59.3 respectively (p<0.001). Reliability was tested in 41/52 caregivers who reported no change in health status between the two administrations of the CPCHILD. The intraclass correlation coefficient was 0.94 (95% confidence interval 0.90–0.97). The CPCHILD seems to be a reliable and valid measure of caregivers' perspectives on the health status, functional limitations, and well-being of these children.
Bright-rimmed clouds (BRCs) are logical laboratories in which to study triggered star formation, however it is difficult in any single cloud to definitively show that star formation was triggered. In this study we compare the hydrodynamic models produced by Vanhala & Cameron (1998) that treat the problems of star-formation triggered by wind-driven implosion to millimeter and submillimeter molecular line observations of BRCs with embedded IRAS sources. These latter sources are derived from a catalog by Sugitani, Fukui, & Ogura (1991) In order to make an accurate comparison we implement a radiative transfer model based on the Sobolev or LVG approximation, and generate molecular line maps which can be directly compared to our observations. We observed several millimeter and submillimeter transitions of CO, C 18O, HCO+, and H13CO+ using the FCRAO, SMT, CSO, and SMA observatories (De Vries, Narayanan, & Snell 2002). We compare these observations with 3 hydrodynamic models of wind-driven shock fronts interacting with pre-existing, but unbound cloud cores. In two cases these model cores are triggered to collapse under the influence of the external wind.