884 research outputs found
Set in Stone: Building America's New Generation of Arts Facilities, 1994-2008
In 2007, just before the domestic economy experienced a major trauma, the Cultural Policy Center at the Harris School and NORC at the University of Chicago launched a national study of cultural building in the United States. It was motivated by multiple requests from leading consultants in the cultural sector who found themselves involved in a steadily growing number of major building projects -- museums, performing arts centers (PACs), and theaters -- and from foundation officers who were frequently asked to help fund these infrastructure projects. With the generous support of the Andrew W. Mellon Foundation, the Kresge Foundation, and the John D. and Catherine T. MacArthur Foundation, we were able to conduct systematic scientific research on cultural building in the United States between 1994 and 2008 and come to a number of conclusions that have important implications for the cultural sector
CpG-ODN-induced sustained expression of BTLA mediating selective inhibition of human B cells.
BTLA (B- and T-lymphocyte attenuator) is a prominent co-receptor that is structurally and functionally related to CTLA-4 and PD-1. In T cells, BTLA inhibits TCR-mediated activation. In B cells, roles and functions of BTLA are still poorly understood and have never been studied in the context of B cells activated by CpG via TLR9. In this study, we evaluated the expression of BTLA depending on activation and differentiation of human B cell subsets in peripheral blood and lymph nodes. Stimulation with CpG upregulated BTLA, but not its ligand: herpes virus entry mediator (HVEM), on B cells in vitro and sustained its expression in vivo in melanoma patients after vaccination. Upon ligation with HVEM, BTLA inhibited CpG-mediated B cell functions (proliferation, cytokine production, and upregulation of co-stimulatory molecules), which was reversed by blocking BTLA/HVEM interactions. Interestingly, chemokine secretion (IL-8 and MIP1β) was not affected by BTLA/HVEM ligation, suggesting that BTLA-mediated inhibition is selective for some but not all B cell functions. We conclude that BTLA is an important immune checkpoint for B cells, as similarly known for T cells
Non-malleable encryption: simpler, shorter, stronger
In a seminal paper, Dolev et al. [15] introduced the notion of non-malleable encryption (NM-CPA). This notion is very intriguing since it suffices for many applications of chosen-ciphertext secure encryption (IND-CCA), and, yet, can be generically built from semantically secure (IND-CPA) encryption, as was shown in the seminal works by Pass et al. [29] and by Choi et al. [9], the latter of which provided a black-box construction. In this paper we investigate three questions related to NM-CPA security: 1. Can the rate of the construction by Choi et al. of NM-CPA from IND-CPA be improved? 2. Is it possible to achieve multi-bit NM-CPA security more efficiently from a single-bit NM-CPA scheme than from IND-CPA? 3. Is there a notion stronger than NM-CPA that has natural applications and can be achieved from IND-CPA security? We answer all three questions in the positive. First, we improve the rate in the scheme of Choi et al. by a factor O(λ), where λ is the security parameter. Still, encrypting a message of size O(λ) would require ciphertext and keys of size O(λ2) times that of the IND-CPA scheme, even in our improved scheme. Therefore, we show a more efficient domain extension technique for building a λ-bit NM-CPA scheme from a single-bit NM-CPA scheme with keys and ciphertext of size O(λ) times that of the NM-CPA one-bit scheme. To achieve our goal, we define and construct a novel type of continuous non-malleable code (NMC), called secret-state NMC, as we show that standard continuous NMCs are not enough for the natural “encode-then-encrypt-bit-by-bit” approach to work. Finally, we introduce a new security notion for public-key encryption that we dub non-malleability under (chosen-ciphertext) self-destruct attacks (NM-SDA). After showing that NM-SDA is a strict strengthening of NM-CPA and allows for more applications, we nevertheless show that both of our results—(faster) construction from IND-CPA and domain extension from one-bit scheme—also hold for our stronger NM-SDA security. In particular, the notions of IND-CPA, NM-CPA, and NM-SDA security are all equivalent, lying (plausibly, strictly?) below IND-CCA securit
Racetrack Betting: Do Bettors Understand the Odds?
\u27!\u27here is considerable literature which concludes that the average person does not understand elementary probability and statistics (Tversky 1971 ). In one experiment of this type subjects were asked whether a family of 6 children born in the order GBGBBG was more or less likely than one in which the birth order was BGBBBB. About 80% chose the first sequence in spite of the fact that both are approximately equally likely, with the second actually being slightly more probable since male births are slightly more common.
This experiment, like most in the field~ is based on questions asked of subjects in a controlled, artificial setting. A naturally occurring setting in which the subjects have a continuing stake in the outcome is a potentially better way to determine whether or not the public understands probability. Examples of such settings are racetracks and stock markets. Racetracks provide the simpler arena; the choice of actions is more restricted and one can bet only for events, not against them as is possible in short selling on the stock market. We therefore analyzed racetrack betting in an attempt to discover the patrons\u27 betting savvy, and we looked only at the simplest type of bet - bets on a horse to win.
Our first assumption is that bettors attempt to win money. Our second one is that they have an internal perception of which horse will win a given race. This perception results in their personal, subjective probability for the outcome of the race. We want to know whether this personal probability has any basis in reality
Towards an Intelligent Tutor for Mathematical Proofs
Computer-supported learning is an increasingly important form of study since
it allows for independent learning and individualized instruction. In this
paper, we discuss a novel approach to developing an intelligent tutoring system
for teaching textbook-style mathematical proofs. We characterize the
particularities of the domain and discuss common ITS design models. Our
approach is motivated by phenomena found in a corpus of tutorial dialogs that
were collected in a Wizard-of-Oz experiment. We show how an intelligent tutor
for textbook-style mathematical proofs can be built on top of an adapted
assertion-level proof assistant by reusing representations and proof search
strategies originally developed for automated and interactive theorem proving.
The resulting prototype was successfully evaluated on a corpus of tutorial
dialogs and yields good results.Comment: In Proceedings THedu'11, arXiv:1202.453
Assessment of targeting accuracy of a low-energy stereotactic radiosurgery treatment for age-related macular degeneration
Age-related macular degeneration (AMD), a leading cause of blindness in the United States, is a neovascular disease that may be controlled with radiation therapy. Early patient outcomes of external beam radiotherapy, however, have been mixed. Recently, a novel multimodality treatment was developed, comprising external beam radiotherapy and concomitant treatment with a vascular endothelial growth factor inhibitor. The radiotherapy arm is performed by stereotactic radiosurgery, delivering a 16 Gy dose in the macula (clinical target volume, CTV) using three external low-energy x-ray fields while adequately sparing normal tissues. The purpose of our study was to test the sensitivity of the delivery of the prescribed dose in the CTV using this technique and of the adequate sparing of normal tissues to all plausible variations in the position and gaze angle of the eye. Using Monte Carlo simulations of a 16 Gy treatment, we varied the gaze angle by ±5° in the polar and azimuthal directions, the linear displacement of the eye ±1mm in all orthogonal directions, and observed the union of the three fields on the posterior wall of spheres concentric with the eye that had diameters between 20 and 28 mm. In all cases, the dose in the CTV fluctuated \u3c6%, the maximum dose in the sclera was \u3c20 Gy, the dose in the optic disc, optic nerve, lens and cornea were \u3c0.7 Gy and the three-field junction was adequately preserved. The results of this study provide strong evidence that for plausible variations in the position of the eye during treatment, either by the setup error or intrafractionmotion, the prescribed dose will be delivered to the CTV and the dose in structures at risk will be kept far below tolerance doses. © 2010 Institute of Physics and Engineering in Medicine
Sources and geodynamics of Early Paleozoic Gabbro Monzodiorite intrusions of the Kuznetsk Alatau Ridge, Siberia
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