Utilizing DNA for electrocatalysis: DNA-Nickel aggregates as anodic electrocatalysts for methanol, ethanol, glycerol, and glucose

pre-printDNA-nickel aggregates were electrodeposited onto glassy carbon electrode surfaces and have shown electrocatalytic activity for oxidation of methanol, ethanol, glycerol, and glucose at room temperature in alkaline solutions. Bulk electrolysis oxidation products identified by 13C NMR include carbonate as methanol, glycerol, and glucose's oxidation products suggesting these three fuels can be deeply oxidized by DNA-nickel aggregates and carbon-carbon bonds can be broken during the oxidation of glycerol and glucose. However, ethanol was only oxidized to acetate. The capability of deep oxidation of methanol, ethanol, glycerol and glucose under relatively moderate conditions makes DNA-nickel a candidate for fuel cell applications

Nickel cysteine complexes as anodic electrocatalysts for fuel cells

pre-printCompared to platinum, nickel is an inexpensive catalyst that can oxidize methanol in alkaline media. There is a desire to increase nickel loading during electrodeposition for improved performance. In this paper, a nickel cysteine complex (NiCys) is used as the precursor for electrodeposition on glassy carbon electrode surfaces. After optimization of cysteine concentration, the surface concentration of NiOOH on NiCys electrodes characterized by cyclic voltammetry in 0.1 M NaOH can reach 1.28 (± 0.32) × 10−7 mol/cm2. The large amount of NiOOH on NiCys electrodes provide 5 times the methanol oxidation current compared to Ni electrodes prepared without cysteine as demonstrated by chronoamperometry at 0.7 V vs. Hg/HgO. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy have been applied to examine surface morphologies and structures of NiCys and Ni electrodes. The analysis reveals that cysteine adjusts the solubility of Ni(OH)2 in 0.1 M NaOH, so more uniform and smaller size nanoparticles are electrodeposited on electrode surfaces compared to Ni electrodes

Intergenerational Effects of Disability Benefits: Evidence from Canadian Social Assistance Programs

Individuals with disabilities face greater challenges in the labor market than able-bodied individuals and a growing body of research is finding that their children also tend to have more developmental problems than the children of able-bodied parents. Can transfer payments help reduce this gap? In this paper, we present the first evidence on how parental disability benefits affect the well-being of children. Using changes in real benefits under ten disability benefit programs in Canada as an identification strategy and Statistics Canada\u27s National Longitudinal Survey of Children and Youth (NLSCY) as the data source on child outcomes, we find strong evidence that higher benefits lead to improvements in children\u27s cognitive and non-cognitive development, as measured by math scores in standardized tests, hyperactive symptoms and emotional anxiety behavior. The effect is larger on children with a disabled mother than on those with a disabled father

College and University Dining Services Administrators’ Intention to Adopt Sustainable Practices: Results from US Institutions

This study examined college and university dining services administrators’ (CUDSAs) intention to adopt sustainable practices. The theory of planned behavior (TPB) including constructs of subjective norm, attitude, perceived behavior control, and personal norm, formed the theoretical framework. A web-based questionnaire was developed, pretested, and distributed to 535 CUDSAs in the U.S.A. Results indicated that subjective norm (pressure from others) had the most influence on CUDSAs’ intention to adopt sustainable practices, followed by attitude and personal norm. Including the personal norm construct in the TPB model reduced unexplained variance by 33.48%. Limitations of this research are generalizability of results due to use of a sample of U.S.A. members of a professional organization (National Association of College and University Food Services) and low response rate. Results suggest that pressure from college administrators and students has the greatest impact on CUDSAs’ decisions to adopt sustainable practices. The question of why some university dining operations are models for sustainability and others have few sustainable practices has not been explored. The dining services director plays a key role in determining sustainability efforts for that operation. This research explored factors influencing a director’s intention to adopt sustainable practices

A Note on the Efficiencies of Sampling Strategies in Two-Stage Bayesian Regional Fine Mapping of a Quantitative Trait

ABSTRACT: In focused studies designed to follow up associations detected in a genome-wide association study (GWAS), investigators can proceed to fine-map a genomic region by targeted sequencing or dense genotyping of all variants in the region, aiming to identify a functional sequence variant. For the analysis of a quantitative trait, we consider a Bayesian approach to fine-mapping study design that incorporates stratification according to a promising GWAS tag SNP in the same region. Improved cost-efficiency can be achieved when the fine-mapping phase incorporates a two-stage design, with identification of a smaller set of more promising variants in a subsample taken in stage 1, followed by their evaluation in an independent stage 2 subsample. To avoid the potential negative impact of genetic model misspecification on inference we incorporate genetic model selection based on posterior probabilities for each competing model. Our simulation study shows that, compared to simple random sampling that ignores genetic information from GWAS, tag-SNP-based stratified sample allocation methods reduce the number of variants continuing to stage 2 and are more likely to promote the functional sequence variant into confirmation studies

The Infrared Imaging Spectrograph (IRIS) for TMT: Volume phase holographic grating performance testing and discussion

Maximizing the grating efficiency is a key goal for the first light instrument IRIS (Infrared Imaging Spectrograph) currently being designed to sample the diffraction limit of the TMT (Thirty Meter Telescope). Volume Phase Holographic (VPH) gratings have been shown to offer extremely high efficiencies that approach 100% for high line frequencies (i.e., 600 to 6000l/mm), which has been applicable for astronomical optical spectrographs. However, VPH gratings have been less exploited in the near-infrared, particularly for gratings that have lower line frequencies. Given their potential to offer high throughputs and low scattered light, VPH gratings are being explored for IRIS as a potential dispersing element in the spectrograph. Our team has procured near-infrared gratings from two separate vendors. We have two gratings with the specifications needed for IRIS current design: 1.51-1.82{\mu}m (H-band) to produce a spectral resolution of 4000 and 1.19- 1.37 {\mu}m (J-band) to produce a spectral resolution of 8000. The center wavelengths for each grating are 1.629{\mu}m and 1.27{\mu}m, and the groove densities are 177l/mm and 440l/mm for H-band R=4000 and J-band R=8000, respectively. We directly measure the efficiencies in the lab and find that the peak efficiencies of these two types of gratings are quite good with a peak efficiency of ~88% at the Bragg angle in both TM and TE modes at H-band, and 90.23% in TM mode, 79.91% in TE mode at J-band for the best vendor. We determine the drop in efficiency off the Bragg angle, with a 20-23% decrease in efficiency at H-band when 2.5 degree deviation from the Bragg angle, and 25%-28% decrease at J-band when 5{\deg} deviation from the Bragg angle.Comment: Proceedings of the SPIE, 9147-33

The InfraRed Imaging Spectrograph (IRIS) for TMT: Reflective ruled diffraction grating performance testing and discussion

We present the efficiency of near-infrared reflective ruled diffraction gratings designed for the InfraRed Imaging Spectrograph (IRIS). IRIS is a first light, integral field spectrograph and imager for the Thirty Meter Telescope (TMT) and narrow field infrared adaptive optics system (NFIRAOS). We present our experimental setup and analysis of the efficiency of selected reflective diffraction gratings. These measurements are used as a comparison sample against selected candidate Volume Phase Holographic (VPH) gratings (see Chen et al., this conference). We investigate the efficiencies of five ruled gratings designed for IRIS from two separate vendors. Three of the gratings accept a bandpass of 1.19-1.37 {\mu}m (J band) with ideal spectral resolutions of R=4000 and R=8000, groove densities of 249 and 516 lines/mm, and blaze angles of 9.86 and 20.54 degrees, respectively. The other two gratings accept a bandpass of 1.51-1.82 {\mu}m (H Band) with an ideal spectral resolution of R=4000, groove density of 141 lines/mm, and blaze angle of 9.86{\deg}. We measure the efficiencies off blaze angle for all gratings and the efficiencies between the polarization transverse magnetic (TM) and transverse electric (TE) states. The peak reflective efficiencies are 98.90 +/- 3.36% (TM) and 84.99 +/- 2.74% (TM) for the H-band R=4000 and J-band R=4000 respectively. The peak reflective efficiency for the J-band R=8000 grating is 78.78 +/- 2.54% (TE). We find that these ruled gratings do not exhibit a wide dependency on incident angle within +/-3{\deg}. Our best-manufactured gratings were found to exhibit a dependency on the polarization state of the incident beam with a ~10-20% deviation, consistent with the theoretical efficiency predictions.Comment: Proceedings of the SPIE, 9147-34

Recovery and upgrade of a device using an auxiliary device

A laptop or other device that breaks down or freezes, e.g., due to malicious software or malfunction, can be made operational again if it returns to a known healthy state. However, the present state of such a device prevents it from autonomously recovering, upgrading to a stable software version, establishing an internet connection to recover or upgrade, or from reliably identifying itself from the contents of its RAM. Per the techniques of this disclosure, an auxiliary device, e.g., a mobile device, reads the read-only memory of the device-under-repair to determine its make, model, and other parameters. A recent, stable operating system and/or other software package suitable for the make and model of the device-under-repair is determined and downloaded by the auxiliary device. The software package is installed by the auxiliary device onto the device-under-repair to complete recovery

A New Mechanism of Model Membrane Fusion Determined from Monte Carlo Simulation

We have carried out extensive Monte Carlo simulations of the fusion of tense apposed bilayers formed by amphiphilic molecules within the framework of a coarse grained lattice model. The fusion pathway differs from the usual stalk mechanism. Stalks do form between the apposed bilayers, but rather than expand radially to form an axial-symmetric hemifusion diaphragm of the trans leaves of both bilayers, they promote in their vicinity the nucleation of small holes in the bilayers. Two subsequent paths are observed: (i) The stalk encircles a hole in one bilayer creating a diaphragm comprised of both leaves of the other intact bilayer, and which ruptures to complete the fusion pore. (ii) Before the stalk can encircle a hole in one bilayer, a second hole forms in the other bilayer, and the stalk aligns and encircles them both to complete the fusion pore. Both pathways give rise to mixing between the cis and trans leaves of the bilayer and allow for transient leakage.Comment: revised version, accepted to Biophys. J. (11 figures

The Infrared Imaging Spectrograph (IRIS) for TMT: Volume Phase Holographic Grating Performance Testing and Discussion

Maximizing the grating efficiency is a key goal for the first light instrument IRIS (Infrared Imaging Spectrograph) currently being designed to sample the diffraction limit of the TMT (Thirty Meter Telescope). Volume Phase Holographic (VPH) gratings have been shown to offer extremely high efficiencies that approach 100% for high line frequencies (i.e., 600 to 6000l/mm), which has been applicable for astronomical optical spectrographs. However, VPH gratings have been less exploited in the near-infrared, particularly for gratings that have lower line frequencies. Given their potential to offer high throughputs and low scattered light, VPH gratings are being explored for IRIS as a potential dispersing element in the spectrograph. Our team has procured near-infrared gratings from two separate vendors. We have two gratings with the specifications needed for IRIS current design: 1.51-1.82μm (H-band) to produce a spectral resolution of 4000 and 1.19-1.37μm (J-band) to produce a spectral resolution of 8000. The center wavelengths for each grating are 1.629μm and 1.27μm, and the groove densities are 177l/mm and 440l/mm for H-band R=4000 and J-band R=8000, respectively. We directly measure the efficiencies in the lab and find that the peak efficiencies of these two types of gratings are quite good with a peak efficiency of ∼88% at the Bragg angle in both TM and TE modes at H-band, and 90.23% in TM mode, 79.91% in TE mode at J-band for the best vendor. We determine the drop in efficiency off the Bragg angle, with a 20-23% decrease in efficiency at H-band when 2.5° deviation from the Bragg angle, and 25%-28% decrease at J-band when 5° deviation from the Bragg angle