Hypersurfaces with nonnegative Ricci curvature in hyperbolic space

Based on properties of n-subharmonic functions we show that a complete, noncompact, properly embedded hypersurface with nonnegative Ricci curvature in hyperbolic space has an asymptotic boundary at infinity of at most two points. Moreover, the presence of two points in the asymptotic boundary is a rigidity condition that forces the hypersurface to be an equidistant hypersurface about a geodesic line in hyperbolic space. This gives an affirmative answer to the question raised by Alexander and Currier in 1990.Comment: 14 page

Low-Noise Amplification of a Continuous Variable Quantum State

We present an experimental realization of a low-noise, phase-insensitive optical amplifier using a four-wave mixing interaction in hot Rb vapor. Performance near the quantum limit for a range of amplifier gains, including near unity, can be achieved. Such low-noise amplifiers are essential for so-called quantum cloning machines and are useful in quantum information protocols. We demonstrate that amplification and ``cloning'' of one half of a two-mode squeezed state is possible while preserving entanglement.Comment: To appear in Physical Review Letters July 3rd. 4 pages, 4 figure

Toward an Ethics of AI Belief

Philosophical research in AI has hitherto largely focused on the ethics of AI. In this paper we, an ethicist of belief and a machine learning scientist, suggest that we need to pursue a novel area of philosophical research in AI - the epistemology of AI, and in particular an ethics of belief for AI, i.e., an ethics of AI belief. Here we take the ethics of belief, a field that has been defined in various ways, to refer to a sub-field within epistemology. This subfield is concerned with the study of possible moral, practical, and other non-alethic dimensions of belief. And in this paper, we will primarily be concerned with the normative question within the ethics of belief of what agents - both human and artificial - ought to believe, rather than with descriptive questions concerning whether certain beliefs meet various evaluative standards such as being true, being justified or warranted, constituting knowledge, and so on. We suggest four topics in extant work in the ethics of (human) belief that can be applied to an ethics of AI belief: doxastic wronging by AI; morally owed beliefs; pragmatic and moral encroachment on AI beliefs; and moral responsibility for AI beliefs. We also indicate an important nascent area of philosophical research in epistemic injustice and AI that has not yet been recognized as research in the ethics of AI belief, but which is so in virtue of concerning moral and practical dimensions of belief

Diversification and hybridization in firm knowledge bases in nanotechnologies

The paper investigates the linkages between the characteristics of technologies and the structure of a firms' knowledge base. Nanotechnologies have been defined as converging technologies that operate at the nanoscale, and which require integration to fulfill their economic promises. Based on a worldwide database of nanofirms, the paper analyses the degree of convergence and the convergence mechanisms within firms. It argues that the degree of convergence in a firm's nano-knowledge base is relatively independent from the size of the firm's nano-knowledge base. However, while firms with small nano-knowledge bases tend to exploit convergence in each of their patents/publications, firms with large nano-knowledge bases tend to separate their nano-R&D activities in the different established fields and achieve diversity through the juxtaposition of the output of these independent activities For more informations http://www.nanoeconomics.eu/

Travel and activity time allocation: An empirical comparison between eight cities in Europe

A study of daily time allocation to travel and out-of-home activity is conducted across eight European cities over three countries: France (Lyon, Grenoble, Strasbourg and Rennes), Switzerland (Geneva, Bern and Zurich) and Belgium (Brussels), based on individual travel survey data collected between 1997 and 2006. The effects of socio-demographic, spatial context, transport availability and city-specific variables are investigated thanks to the Cox proportional hazard model. The results indicate that socio-demographic characteristics and city (or country) specific effect play a major role while residential density and proximity to high level road or public transport networks have a very limited impact on time budgets for travel and out-of-home activities.Travel ; Activity ; Time allocation ; Cities ; Europe ; Duration model

Preliminary Assessment of Growing Oyster Mushroom, Pleurotus sajor-caju on Coconut Husk Substrate Supplemented with Different Amounts of Copra Cake

Mushroom cultivation is a newly introduced technology in the Marshall Islands to promote food security and community health due to its soluble fiber content and nutritive values. Mushroom is also known to have naturally occurring beta-glucans that could prevent high cholesterol and some other non-communicable disease (NCDs). Majuro Atoll has an ample amount of coconut husk and copra cake, a by-product from Tobolar Copra Processing Plant. The study aimed to assess the possibility of using copra cake for mushroom cultivation. The capability of oyster mushroom in utilizing coconut by-product was assessed in terms of mycelial growth, number of fruiting body, cap diameter and biological efficiency conversion (BEC). The mushroom growing media used for this study were composed of shredded coconut husk, dolomitic lime, brown sugar and varying amounts (0%, 5%, 10%, 15%, 20%, 25%) of copra cake with 45-60% moisture content. It was hypothesized that copra cake supplementation will increase production yield. Treatments were distributed in 10 replications and data were analyzed using the Duncan’s Multiple Test Range at 5% level of significance. Mycelial growth occurred in all treatments in the following order: 10%\u3e 0%, 5%, 15% \u3e20% \u3e25%. Thin mycelial growth occurred at 0%, and slowest growth was observed for 25%. Fruiting bodies did not take place for treatment without copra cake supplementation (0%). The overall growth performance was observed to be very favorable at 10% copra cake supplementation. This result suggests that coconut husk supplemented with the right amount of copra cake could be utilized effectively as locally available materials for mushroom cultivation

On nonnegatively curved hypersurfaces in hyperbolic space

In this paper we prove a conjecture of Alexander and Currier that states, except for covering maps of equidistant surfaces in hyperbolic 3-space, a complete, nonnegatively curved immersed hypersurface in hyperbolic space is necessarily properly embedded