Separation and Electrical Properties of Self-Organized Graphene/Graphite Layers

Intrinsic layered structure of graphite is the source of ongoing and expanding search of ways of obtaining low-cost and promising graphite thin layers. We report on a novel method of obtaining and separating rubbed graphite sheets by using water soluble NaCl substrate. The electrical behavior of sheets was characterized by current-voltage measurements. An in-plane electrical unisotropy depending on rubbing direction is discovered. Optical microscopy observations combined with discovered non-linear electrical behavior revealed that friction leads to the formation of sheet makeup which contain an optically transparent lamina of self-organized few-layer graphene.Comment: 5 pages, 4 figure

Superaromatics: The key to a unified cosmic dust theory

The theory of Superaromatics, the key to a unified cosmic dust theory, was constructed by analyzing several thousand astronomical features covering every major aspect of astrophysics and astrochemistry relating to dust. To insure consistency between disciplines, the logical structure of the conclusions in each field was checked rather than accepting the current consensus. No substantial contradictory features are known to the author. The analysis falls into seven major parts: (1) kinetics of grain formation and destruction; (2) optical spectra of the interstellar medium (ISM); (3) meteorite interplanetary dust particle (IPD) chemistry; (4) structure and chemistry of the interstellar medium arising from surface catalysis; (6) dynamics of circumstellar and interstellar dust clouds, including galactic morphology; and (7) the chemistry and physics of previously unidentified compounds. Only tentative conclusions are presented here. The principle conclusion is that quantum mechanics as it is normally formulated is incomplete. The probable cause is that it is formulated with complex numbers rather than the more fundamental quaternion system. The manifestation in astrochemistry is that the most stable compounds are superaromatic and exotic enough to confound most classical analysis

Global Integration and Growth in Honduras and Nicaragua

Globalization, Latin America and the Caribbean, Sustainable growth

Location-Based Preferences in Federal and Federally Funded Contracting: An Overview of the Law

[Excerpt] The recession that began in December 2007 has prompted increased interest among some Members of Congress and their constituents in legal authorities that could require or allow federal agencies to prefer contractors in one state or locality over those in other states or localities. Federal spending on procurement contracts has remained high, reaching $523.9 billion in FY2009, at a time when many other businesses have scaled back their purchases of goods and services. However, this spending has historically been localized in three to five states, which receive nearly half of all federal procurement dollars, prompting concerns about whether other states receive their “fair share.” Such concerns may be overstated, given that many contracts must be performed in or near Washington, DC, and shifting the place of performance of existing contracts from one state to another would generally not decrease overall unemployment. Nonetheless, geographic distribution of federal spending and federal funding is often a concern during economic downturns. This report discusses constitutional and other legal issues related to the creation and implementation of location-based preferences in federal contracting, as well as summarizes key authorities requiring or allowing federal agencies to “favor” contractors located in specific places. The report does not address federal preferences for domestic products or provisions of federal law that could, depending upon their implementation, effectively prefer local contractors, such as project labor agreements

The Multifarious Role of Microglia in Brain Metastasis

The immune landscape in brain metastasis is a very heterogeneous framework. Amongst a broad plethora of cells within the tumor microenvironment, the presence of activated microglia has been perfectly described. The innate role of microglial cells is to detect and eliminate any insults that may disturb the regular behavior of the brain. As part of its defensive role, it releases pro- and anti-inflammatory cytokines that aim to modulate the inflammatory scenario at the metastatic foci. However, the long term effects that these cells may exert on the metastatic progression is not clear. One of the biggest challenges in the field is to distinguish between brain resident microglial cells and infiltrated bone-marrow derived macrophages. Part of this issue is the fact that both cell types share similar phenotypes. Current studies are based on the modulation of the immune response against cancer cells (immunotherapy). However, most of current clinical trials and newly developed drugs focus on the adaptive immune response (e.g., immune blockade check-points). Additionally, the unique structure of the central nervous system with the presence of the blood-brain barrier have hindered a significant advance in novel therapies against brain metastasis. In this manuscript, we describe current advances in characterization of tumor-associated microglia and macrophages, the importance of microglia during the anti-cancerous response, and the future direction for the development of new strategies against this complex disease

On the robustness of least-squares Monte Carlo (LSM) for pricing American derivatives

This paper analyses the robustness of Least-Squares Monte Carlo, a technique recently proposed by Longstaff and Schwartz (2001) for pricing American options. This method is based on least-squares regressions in which the explanatory variables are certain polynomial functions. We analyze the impact of different basis functions on option prices. Numerical results for American put options provide evidence that a) this approach is very robust to the choice of different alternative polynomials and b) few basis functions are required. However, these conclusions are not reached when analyzing more complex derivatives.Least-Squares Monte Carlo, option pricing, American options