392 research outputs found
Realistic two-nucleon potentials for the relativistic two-nucleon Schroedinger equation
The potentials in the nonrelativistic (relativistic) nucleon-nucleon
(NN) Schroedingerequation are related by a quadratic equation. That equation is
numerically solved, thus providing phase equivalent v- potentials related for
instance to the high precision NN potentials, which are adjusted to NN phase
shift and mixing parameters in a nonrelativistic Schroedinger equation. The
relativistic NN potentials embedded in a three-nucleon (3N)system for total NN
momenta different from zero are also constructed in a numerically precise
manner. They enter into the relativistic interacting 3N mass operator, which is
needed for relativistic 3N calculations for bound and scattering states.Comment: 6 pages, 4figures, 2 tables; typos adde
Time-Distance Seismology of the Solar Corona with CoMP
We employ a sequence of Doppler images obtained with the Coronal
Multi-channel Polarimeter (CoMP) instrument to perform time-distance seismology
of the solar corona. We construct the first k-omega diagrams of the region.
These allow us to separate outward and inward propagating waves and estimate
the spatial variation of the plane-of-sky projected phase speed, and the
relative amount of outward and inward directed wave power. The disparity
between outward and inward wave power and the slope of the observed power law
spectrum indicate that low-frequency Alfvenic motions suffer significant
attenuation as they propagate, consistent with isotropic MHD turbulence.Comment: In Press ApJ. 8 pages and 8 color figure
Electromagnetic Scanning of Beef Quarters to Predict Carcass and Primal Lean Content
To study the use of electromagnetic scanning in prediction of lean content in beef carcasses and cuts, 100 beef cattle (60 steers and 40 heifers), representing a broad range in external fat thickness (. 1 to 2.9 cm) and live weight (414 to 742 kg), were selected. Chilled right sides were divided into streamlined (foreshank, brisket, and ventral plate removed) forequarters (FQ) and full hindquarters (HQ) and scanned. Primal rounds, loins, ribs, and chucks were fabricated from the right side, scanned, and physically separated into lean, fat, and bone. Prediction equations for dissected lean content and percentage of lean included the peak of the electromagnetic scan response curve (obtained from scanning the HQ or FQ), length, temperature and weight of the scanned cut, and fat thickness at the 12th rib. Using the coefficient of determination, root mean square error, and Mallows\u27 Cp statistic, the best model for each dependent variable (weight and percentage of lean) that included up to five independent variables was selected. Prediction equations for the HQ or FQ of steers accounted for 84 to 93% of the variation in lean weight of beef sides and quarters and 71 to 93% of primals. Sixty-one to 75% of the variation in percentage of lean in sides and quarters and 48 to 65% of primals was also explained. Similar results were obtained for heifer carcasses. Predicting percentage of lean in any scanned cut, rather than weight of lean, accounted for less of the variation. Weight and fat thickness contributed significantly when predicting percentage of lean. These data indicate that electromagnetic scanning is capable of objectively measuring lean content in beef quarters and primals
The Ethical Dilemma of Information Asymmetry in Innovation: Reputation, Investors and Noise in the Innovation Channel.
A sufficient and steady stream of innovations is widely seen as a basis for healthy modern economies. Governments divert substantial resources from other purposes in society to increase innovation. Yet the failure rate among innovative SMEs is high, suggesting that resources are wasted. Avoiding such waste is a challenge for both governments and investors, but also raises a question for the innovative company, namely how to build and fund the\ud
enterprise on an ethical basis. The dilemma of giving in to temptations to ‘cut corners’ clearly exists, for example to exploit the inevitable asymmetry of information arising in innovation and potentially deploy this in support of misleading claims about specific capabilities and/or the unjustified creation and exploitation of reputation. This is consistent with Olaf Fisscher’s finding that entrepreneurs starting new ventures tend to exhibit an inherent bias towards compromising their own values in order to succeed at any cost. When the innoSME’s aspirations are unrealistic or the proposed innovations are of marginal value, the ethical issues are broader and extend also to those who are potential financiers. Noting this as a gap in the ethics literature, we argue that the current situation fails to match economic and ethical ideals and that work is needed to develop tools which allow those who provide finance and support for innovation to target it more effectively at those who have a prospect of successfully launching genuine innovations and thus reduce the ‘noise’ in the innovation field
Spectral method for matching exterior and interior elliptic problems
A spectral method is described for solving coupled elliptic problems on an
interior and an exterior domain. The method is formulated and tested on the
two-dimensional interior Poisson and exterior Laplace problems, whose solutions
and their normal derivatives are required to be continuous across the
interface. A complete basis of homogeneous solutions for the interior and
exterior regions, corresponding to all possible Dirichlet boundary values at
the interface, are calculated in a preprocessing step. This basis is used to
construct the influence matrix which serves to transform the coupled boundary
conditions into conditions on the interior problem. Chebyshev approximations
are used to represent both the interior solutions and the boundary values. A
standard Chebyshev spectral method is used to calculate the interior solutions.
The exterior harmonic solutions are calculated as the convolution of the
free-space Green's function with a surface density; this surface density is
itself the solution to an integral equation which has an analytic solution when
the boundary values are given as a Chebyshev expansion. Properties of Chebyshev
approximations insure that the basis of exterior harmonic functions represents
the external near-boundary solutions uniformly. The method is tested by
calculating the electrostatic potential resulting from charge distributions in
a rectangle. The resulting influence matrix is well-conditioned and solutions
converge exponentially as the resolution is increased. The generalization of
this approach to three-dimensional problems is discussed, in particular the
magnetohydrodynamic equations in a finite cylindrical domain surrounded by a
vacuum
Graphene on Au-coated SiOx substrate: Its core-level photoelectron micro-spectroscopy study
The core-level electronic structures of the exfoliated graphene sheets on a
Au-coated SiOx substrate have been studied by synchrotron radiation
photoelectron spectroscopy (SR-PES) on a micron-scale. The graphene was firstly
demonstrated its visibility on the Au-coated SiOx substrate by micro-optical
characterization, and then conducted into SR-PES study. Because of the
elimination of charging effect, precise C 1s core-level characterization
clearly shows graphitic and contaminated carbon states of graphene. Different
levels of Au-coating-induced p-type doping on single- and double-layer graphene
sheets were also examined in the C 1s core-level shift. The Au-coated SiOx
substrate can be treated as a simple but high-throughput platform for in situ
studying graphene under further hybridization by PES
RNA Viral Community in Human Feces: Prevalence of Plant Pathogenic Viruses
The human gut is known to be a reservoir of a wide variety of microbes, including viruses. Many RNA viruses are known to be associated with gastroenteritis; however, the enteric RNA viral community present in healthy humans has not been described. Here, we present a comparative metagenomic analysis of the RNA viruses found in three fecal samples from two healthy human individuals. For this study, uncultured viruses were concentrated by tangential flow filtration, and viral RNA was extracted and cloned into shotgun viral cDNA libraries for sequencing analysis. The vast majority of the 36,769 viral sequences obtained were similar to plant pathogenic RNA viruses. The most abundant fecal virus in this study was pepper mild mottle virus (PMMV), which was found in high concentrations—up to 10(9) virions per gram of dry weight fecal matter. PMMV was also detected in 12 (66.7%) of 18 fecal samples collected from healthy individuals on two continents, indicating that this plant virus is prevalent in the human population. A number of pepper-based foods tested positive for PMMV, suggesting dietary origins for this virus. Intriguingly, the fecal PMMV was infectious to host plants, suggesting that humans might act as a vehicle for the dissemination of certain plant viruses
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Molecular and Microbial Microenvironments in Chronically Diseased Lungs Associated with Cystic Fibrosis.
To visualize the personalized distributions of pathogens and chemical environments, including microbial metabolites, pharmaceuticals, and their metabolic products, within and between human lungs afflicted with cystic fibrosis (CF), we generated three-dimensional (3D) microbiome and metabolome maps of six explanted lungs from three cystic fibrosis patients. These 3D spatial maps revealed that the chemical environments differ between patients and within the lungs of each patient. Although the microbial ecosystems of the patients were defined by the dominant pathogen, their chemical diversity was not. Additionally, the chemical diversity between locales in the lungs of the same individual sometimes exceeded interindividual variation. Thus, the chemistry and microbiome of the explanted lungs appear to be not only personalized but also regiospecific. Previously undescribed analogs of microbial quinolones and antibiotic metabolites were also detected. Furthermore, mapping the chemical and microbial distributions allowed visualization of microbial community interactions, such as increased production of quorum sensing quinolones in locations where Pseudomonas was in contact with Staphylococcus and Granulicatella, consistent with in vitro observations of bacteria isolated from these patients. Visualization of microbe-metabolite associations within a host organ in early-stage CF disease in animal models will help elucidate the complex interplay between the presence of a given microbial structure, antibiotics, metabolism of antibiotics, microbial virulence factors, and host responses.IMPORTANCE Microbial infections are now recognized to be polymicrobial and personalized in nature. Comprehensive analysis and understanding of the factors underlying the polymicrobial and personalized nature of infections remain limited, especially in the context of the host. By visualizing microbiomes and metabolomes of diseased human lungs, we reveal how different the chemical environments are between hosts that are dominated by the same pathogen and how community interactions shape the chemical environment or vice versa. We highlight that three-dimensional organ mapping methods represent hypothesis-building tools that allow us to design mechanistic studies aimed at addressing microbial responses to other microbes, the host, and pharmaceutical drugs
The Stability of Bredigite and Other Ca-Mg Silicates
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65844/1/j.1151-2916.1980.tb10213.x.pd
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