Segregation in social networks based on acquaintanceship and trust

Using newly collected data from the General Social Survey, we compare levels of segregation by race and along other potential dimensions of social cleavage for ties defined in terms of trust and acquaintanceship. We further estimate the size of the trust network and compare its size and structure to recent estimates obtained from the 2004 General Social Survey by McPherson et al. Americans are less disconnected than other recent evidence suggests. However, if racial segregation is the standard, then America is highly segregated across class and values dimensions as well as race and ethnicity. We further find that segregation is insensitive to tie strength. Scholars have long found homophily in close ties, while scholars such as Putnam have looked to weak ties for socially integrative bridging social capital. However, bridging social capital does not appear to be more plentiful for weak ties than it is for strong ties. --

Designing Vibrotactile Widgets with Printed Actuators and Sensors

Physical controls are fabricated through complicated assembly of parts requiring expensive machinery and are prone to mechanical wear. One solution is to embed controls directly in interactive surfaces, but the proprioceptive part of gestural interaction that makes physical controls discoverable and usable solely by hand gestures is lost and has to be compensated, by vibrotactile feedback for instance. Vibrotactile actuators face the same aforementioned issues as for physical controls. We propose printed vibrotactile actuators and sensors. They are printed on plastic sheets, with piezoelectric ink for actuation, and with silver ink for conductive elements, such as wires and capacitive sensors. These printed actuators and sensors make it possible to design vibrotactile widgets on curved surfaces, without complicated mechanical assembly

Generation of two-color polarization-entangled optical beams with a self-phase-locked two-crystal Optical Parametric Oscillator

A new device to generate polarization-entangled light in the continuous variable regime is introduced. It consists of an Optical Parametric Oscillator with two type-II phase-matched non-linear crystals orthogonally oriented, associated with birefringent elements for adjustable linear coupling. We give in this paper a theoretical study of its classical and quantum properties. It is shown that two optical beams with adjustable frequencies and well-defined polarization can be emitted. The Stokes parameters of the two beams are entangled. The principal advantage of this setup is the possibility to directly generate polarization entangled light without the need of mixing four modes on beam splitters as required in current experimental setups. This device opens new directions for the study of light-matter interfaces and generation of multimode non-classical light and higher dimensional phase space

The Cosmic Linear Anisotropy Solving System (CLASS) IV: Efficient implementation of non-cold relics

We present a new flexible, fast and accurate way to implement massive neutrinos, warm dark matter and any other non-cold dark matter relics in Boltzmann codes. For whatever analytical or numerical form of the phase-space distribution function, the optimal sampling in momentum space compatible with a given level of accuracy is automatically found by comparing quadrature methods. The perturbation integration is made even faster by switching to an approximate viscous fluid description inside the Hubble radius, which differs from previous approximations discussed in the literature. When adding one massive neutrino to the minimal cosmological model, CLASS becomes just 1.5 times slower, instead of about 5 times in other codes (for fixed accuracy requirements). We illustrate the flexibility of our approach by considering a few examples of standard or non-standard neutrinos, as well as warm dark matter models.Comment: 23 pages, 8 figures, 3 tables. Matches published version. Code available at http://class-code.ne

Segregation in social networks based on acquaintanceship and trust

Using recently collected data from the 2006 General Social Survey, we compare levels of segregation by race and along other dimensions of potential social cleavage in the contemporary United States. Americans are not as isolated as other recent evidence suggests. However, hopes that "bridging" social capital is more common in broader acquaintanceship networks than in core networks are not supported by the GSS data. Instead, the entire acquaintanceship network appears to be as segregated as the more restricted and much smaller network based on trust. Social divisions based on religiosity, political ideology, family behaviors and socioeconomic standing are high and in some cases rival racial segregation in their intensity. The major challenge to social integration today comes less from the risk of social isolation--complete isolation is rare--than from the tendency of many Americans to isolate themselves from others who differ on race, political ideology, level of religiosity, and other salient aspects of social identity

Revisiting the missing protein-coding gene catalog of the domestic dog

<p>Abstract</p> <p>Background</p> <p>Among mammals for which there is a high sequence coverage, the whole genome assembly of the dog is unique in that it predicts a low number of protein-coding genes, ~19,000, compared to the over 20,000 reported for other mammalian species. Of particular interest are the more than 400 of genes annotated in primates and rodent genomes, but missing in dog.</p> <p>Results</p> <p>Using over 14,000 orthologous genes between human, chimpanzee, mouse rat and dog, we built multiple pairwise synteny maps to infer short orthologous intervals that were targeted for characterizing the canine missing genes. Based on gene prediction and a functionality test using the ratio of replacement to silent nucleotide substitution rates (<it>d</it>_N/<it>d</it>_S), we provide compelling structural and functional evidence for the identification of 232 new protein-coding genes in the canine genome and 69 gene losses, characterized as undetected gene or pseudogenes. Gene loss phyletic pattern analysis using ten species from chicken to human allowed us to characterize 28 canine-specific gene losses that have functional orthologs continuously from chicken or marsupials through human, and 10 genes that arose specifically in the evolutionary lineage leading to rodent and primates.</p> <p>Conclusion</p> <p>This study demonstrates the central role of comparative genomics for refining gene catalogs and exploring the evolutionary history of gene repertoires, particularly as applied for the characterization of species-specific gene gains and losses.</p

Entanglement entropy in collective models

We discuss the behavior of the entanglement entropy of the ground state in various collective systems. Results for general quadratic two-mode boson models are given, yielding the relation between quantum phase transitions of the system (signaled by a divergence of the entanglement entropy) and the excitation energies. Such systems naturally arise when expanding collective spin Hamiltonians at leading order via the Holstein-Primakoff mapping. In a second step, we analyze several such models (the Dicke model, the two-level BCS model, the Lieb-Mattis model and the Lipkin-Meshkov-Glick model) and investigate the properties of the entanglement entropy in the whole parameter range. We show that when the system contains gapless excitations the entanglement entropy of the ground state diverges with increasing system size. We derive and classify the scaling behaviors that can be met.Comment: 11 pages, 7 figure

Species D Adenoviruses as Oncolytics against B-cell Cancers

Purpose: Oncolytic viruses are self-amplifying anticancer agents that make use of the natural ability of viruses to kill cells. Adenovirus serotype 5 (Ad5) has been extensively tested against solid cancers, but less so against B-cell cancers because these cells do not generally express the coxsackie and adenoviral receptor (CAR). To determine whether other adenoviruses might have better potency, we mined the adenovirus virome of 55 serotypes for viruses that could kill B-cell cancers. Experimental Design: Fifteen adenoviruses selected to represent Ad species B, C, D, E, and F were tested in vitro against cell lines and primary patient B-cell cancers for their ability to infect, replicate in, and kill these cells. Select viruses were also tested against B-cell cancer xenografts in immunodeficient mice. Results: Species D adenoviruses mediated most robust killing against a range of B-cell cancer cell lines, against primary patient marginal zone lymphoma cells, and against primary patient CD138þ myeloma cells in vitro. When injected into xenografts in vivo, single treatment with select species D viruses Ad26 and Ad45 delayed lymphoma growth. Conclusions: Relatively unstudied species Dadenoviruses have a unique ability to infect and replicate in B-cell cancers as compared with other adenovirus species. These data suggest these viruses have unique biology in B cells and support translation of novel species D adenoviruses as oncolytics against B-cell cancers

Photon-number discrimination without a photon counter and its application to reconstructing non-Gaussian states

The nonlinearity of a conditional photon-counting measurement can be used to "de-Gaussify" a Gaussian state of light. Here we present and experimentally demonstrate a technique for photon-number resolution using only homodyne detection. We then apply this technique to inform a conditional measurement, unambiguously reconstructing the statistics of the non-Gaussian one- and two-photon-subtracted squeezed vacuum states. Although our photon-number measurement relies on ensemble averages and cannot be used to prepare non-Gaussian states of light, its high efficiency, photon-number- resolving capabilities, and compatibility with the telecommunications band make it suitable for quantum-information tasks relying on the outcomes of mean values