5,971 research outputs found
Found: High Surface Brightness Compact Galaxies
We are using the 2dF spectrograph to make a survey of all objects (`stars'
and `galaxies') in a 12 sq.deg region towards the Fornax cluster. We have
discovered a population of compact emission-line galaxies unresolved on
photographic sky survey plates and therefore missing in most galaxy surveys
based on such material. These galaxies are as luminous as normal field
galaxies. Using H-alpha to estimate star formation they contribute at least an
additional 5 per cent to the local star formation rate.Comment: To appear in "The Low Surface Brightness Universe", IAU Coll 171,
eds. J.I. Davies et al., A.S.P. Conference Series. 3 pages, LaTex, 1
encapsulated ps-figure, requires paspconf.st
Recommended from our members
Wnt5a induces ROR1 to recruit cortactin to promote breast-cancer migration and metastasis.
ROR1 is a conserved oncoembryonic surface protein expressed in breast cancer. Here we report that ROR1 associates with cortactin in primary breast-cancer cells or in MCF7 transfected to express ROR1. Wnt5a also induced ROR1-dependent tyrosine phosphorylation of cortactin (Y421), which recruited ARHGEF1 to activate RhoA and promote breast-cancer-cell migration; such effects could be inhibited by cirmtuzumab, a humanized mAb specific for ROR1. Furthermore, treatment of mice bearing breast-cancer xenograft with cirmtuzumab inhibited cortactin phosphorylation in vivo and impaired metastatic development. We established that the proline at 841 of ROR1 was required for it to recruit cortactin and ARHGEF1, activate RhoA, and enhance breast-cancer-cell migration in vitro or development of metastases in vivo. Collectively, these studies demonstrate that the interaction of ROR1 with cortactin plays an important role in breast-cancer-cell migration and metastasis
A 2D Chaotic Oscillator for Analog IC
In this paper, we have proposed the design of an analog two-dimensional (2D) discrete-time chaotic oscillator. 2D chaotic systems are studied because of their more complex chaotic behavior compared to one-dimensional (1D) chaotic systems. The already published works on 2D chaotic systems are mainly focused either on the complex analytical combinations of familiar 1D chaotic maps such as Sine map, Logistic map, Tent map, and so on, or off-the-shelf component-based analog circuits. Due to complex hardware requirements, neither of them is feasible for hardware-efficient integrated circuit (IC) implementations. To the best of our knowledge, this proposed work is the first-ever report of an analog 2D discrete-time chaotic oscillator design that is suitable for hardware-constrained IC implementations. The chaotic performance of the proposed design is analyzed with bifurcation plots, the transient response, 2D Lyapunov exponent, and correlation coefficient measurements. It is demonstrated that the proposed design exhibits promising chaotic behavior with low hardware cost. The real-world application of the proposed 2D chaotic oscillator is presented in a random number generator (RNG) design. The applicability of the RNG in cryptography is verified by passing the generated random sequence through four standard statistical tests namely, NIST, FIPS, TestU01, and Diehard
Fractal Patterns in the Parameter Space of Bi-stable Duffing Oscillator
We study the dissipative bi-stable Duffing oscillator with equal energy wells
and observe fractal patterns in the parameter space of driving frequency,
forcing amplitude, and damping ratio. Our numerical investigation reveals the
Hausdorff fractal dimension of the boundaries that separate the oscillator's
intra-well and inter-well behaviors. Furthermore, we categorize the inter-well
behaviors as three steady-state types: switching, reverting, and vacillating.
While fractal patterns in the phase space are well-known and heavily studied,
our results point to a new research direction about fractal patterns in the
parameter space. Another implication of this study is that the vibration of a
continuous bi-stable system modeled using a single-mode approximation also
manifests fractal patterns in the parameter space. In addition, our findings
can guide the design of next-generation bi-stable and multi-stable mechanical
metamaterials
Benefits of Implementing a Daily Safety Brief at the Baystate Children’s Hospital
Nursing Scholarship Symposium Event Posters.https://scholarlycommons.libraryinfo.bhs.org/nurs_presentations/1001/thumbnail.jp
- …