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Nanometer patterning of water by tetraanionic ferrocyanide stabilized in aqueous nanodrops.
Formation of the small, highly charged tetraanion ferrocyanide, Fe(CN)64-, stabilized in aqueous nanodrops is reported. Ion-water interactions inside these nanodrops are probed using blackbody infrared radiative dissociation, infrared photodissociation (IRPD) spectroscopy, and molecular modeling in order to determine how water molecules stabilize this highly charged anion and the extent to which the tetraanion patterns the hydrogen-bonding network of water at long distance. Fe(CN)64-(H2O)38 is the smallest cluster formed directly by nanoelectrospray ionization. Ejection of an electron from this ion to form Fe(CN)63-(H2O)38 occurs with low-energy activation, but loss of a water molecule is favored at higher energy indicating that water molecule loss is entropically favored over loss of an electron. The second solvation shell is almost complete at this cluster size indicating that nearly two solvent shells are required to stabilize this highly charged anion. The extent of solvation necessary to stabilize these clusters with respect to electron loss is substantially lower through ion pairing with either H+ or K+ (n = 17 and 18, respectively). IRPD spectra of Fe(CN)64-(H2O) n show the emergence of a free O-H water molecule stretch between n = 142 and 162 indicating that this ion patterns the structure of water molecules within these nanodrops to a distance of at least ∼1.05 nm from the ion. These results provide new insights into how water stabilizes highly charged ions and demonstrate that highly charged anions can have a significant effect on the hydrogen-bonding network of water molecules well beyond the second and even third solvation shells
Pseudo Bayesian Estimation of One-way ANOVA Model in Complex Surveys
We devise survey-weighted pseudo posterior distribution estimators under
2-stage informative sampling of both primary clusters and secondary nested
units for a one-way ANOVA population generating model as a simple canonical
case where population model random effects are defined to be coincident with
the primary clusters. We consider estimation on an observed informative sample
under both an augmented pseudo likelihood that co-samples random effects, as
well as an integrated likelihood that marginalizes out the random effects from
the survey-weighted augmented pseudo likelihood. This paper includes a
theoretical exposition that enumerates easily verified conditions for which
estimation under the augmented pseudo posterior is guaranteed to be consistent
at the true generating parameters. We reveal in simulation that both approaches
produce asymptotically unbiased estimation of the generating hyperparameters
for the random effects when a key condition on the sum of within cluster
weighted residuals is met. We present a comparison with frequentist EM and a
methods that requires pairwise sampling weights.Comment: 46 pages, 9 figure
Utilizing cow-calf producer information to increase profits in retained ownership of beef cattle
Retained ownership has been found to be a profitable endeavor, yet many cow-calf producers choose not to retain their calves. While this paper does not directly explore the reasons producers might have for not retaining ownership, which may include uncertainty, it does explore innovative use of asymmetrical information that might reduce some of the uncertainty. Results are summarized in a regression analysis similar to a Hedonic price model where birth weight, weaning weight, and weaning age are found to be important factors to consider when selecting animals to retain.Asymmetrical Information, Hedonic Price Model, Beef, Retained Ownership, Producer Profitability, Farm Management, Livestock Production/Industries, Production Economics, D82, M31, Q13,
Long distance ion-water interactions in aqueous sulfate nanodrops persist to ambient temperatures in the upper atmosphere.
The effect of temperature on the patterning of water molecules located remotely from a single SO42- ion in aqueous nanodrops was investigated for nanodrops containing between 30 and 55 water molecules using instrument temperatures between 135 and 360 K. Magic number clusters with 24, 36 and 39 water molecules persist at all temperatures. Infrared photodissociation spectroscopy between 3000 and 3800 cm-1 was used to measure the appearance of water molecules that have a free O-H stretch at the nanodroplet surface and to infer information about the hydrogen bonding network of water in the nanodroplet. These data suggest that the hydrogen bonding network of water in nanodrops with 45 water molecules is highly ordered at 135 K and gradually becomes more amorphous with increasing temperature. An SO42- dianion clearly affects the hydrogen bonding network of water to at least ∼0.71 nm at 135 K and ∼0.60 nm at 340 K, consistent with an entropic drive for reorientation of water molecules at the surface of warmer nanodrops. These distances represent remote interactions into at least a second solvation shell even with elevated instrumental temperatures. The results herein provide new insight into the extent to which ions can structurally perturb water molecules even at temperatures relevant to Earth's atmosphere, where remote interactions may assist in nucleation and propagation of nascent aerosols
Online open neuroimaging mass meta-analysis
We describe a system for meta-analysis where a wiki stores numerical data in
a simple format and a web service performs the numerical computation.
We initially apply the system on multiple meta-analyses of structural
neuroimaging data results. The described system allows for mass meta-analysis,
e.g., meta-analysis across multiple brain regions and multiple mental
disorders.Comment: 5 pages, 4 figures SePublica 2012, ESWC 2012 Workshop, 28 May 2012,
Heraklion, Greec
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