3,460 research outputs found
Nonmilitary Threats to Soviet National Security
Except, perhaps, in the view of the most brazen martinet, national power is not an end in itself. Rather, it is a means to an end set of ends which usually include such goals as the survival of the nation-state, its culture and its way of life, the improvement in the quality of life of its citizens; and the state\u27s continued ability to increase its infuence with other states in the pursuit of these goals. From this broader perspective, the national security of the Soviet Union is vulnerable to serious structured and systematic industrial and agricultural problems as well as demographic demographic trends which threaten to tear apart from with in the last of the world\u27s great multinational empires
Scaffolding Independence: Inside the Classroom, Outside the Classroom, and in the Spaces in Between
This piece outlines the author\u27s educational concept, Scaffolding Indpendence, and its applications in early college classrooms over nearly a decade. The author also introduces the works of other dynamic, innovative educators—The Scaffolding Indpendence Team—who created educational modules to codify early college teaching practices
On symplectic fillings
In this note we make several observations concerning symplectic fillings. In
particular we show that a (strongly or weakly) semi-fillable contact structure
is fillable and any filling embeds as a symplectic domain in a closed
symplectic manifold. We also relate properties of the open book decomposition
of a contact manifold to its possible fillings. These results are also useful
in proving property P for knots [P Kronheimer and T Mrowka, Geometry and
Topology, 8 (2004) 295-310, math.GT/0311489] and in showing the contact
Heegaard Floer invariant of a fillable contact structure does not vanish [P
Ozsvath and Z Szabo, Geometry and Topology, 8 (2004) 311-334, math.GT/0311496].Comment: Published electronically at
http://www.maths.warwick.ac.uk/agt/AGTVol4/agt-4-5.abs.htm
Where Do Riders Park Dockless, Shared Electric Scooters? Findings from San Jose, California
Dockless, shared, electric kick-scooters started popping up on U.S. city streets without warning in 2017. Reaction to the shared scooters came swiftly and strongly. On the one hand, the scooters have proven popular with riders, attracting investment capital and expanding service to additional cities. But others have been less enthusiastic, with a central complaint being how shared scooters are parked. This perspective explores the extent to which parked shared scooters pose a problem to others on streets, sidewalks, and public spaces, using empirical evidence documenting where scooters have been parked in downtown San Jose, California
Quality assessment of microarrays: Visualization of spatial artifacts and quantitation of regional biases
BACKGROUND: Quality-control is an important issue in the analysis of gene expression microarrays. One type of problem is regional bias, in which one region of a chip shows artifactually high or low intensities (or ratios in a two-channel array) relative to the majority of the chip. Current practice in quality assessment for microarrays does not address regional biases. RESULTS: We present methods implemented in R for visualizing regional biases and other spatial artifacts on spotted microarrays and Affymetrix chips. We also propose a statistical index to quantify regional bias and investigate its typical distribution on spotted and Affymetrix arrays. We demonstrate that notable regional biases occur on both Affymetrix and spotted arrays and that they can make a significant difference in the case of spotted microarray results. Although strong biases are also seen at the level of individual probes on Affymetrix chips, the gene expression measures are less affected, especially when the RMA method is used to summarize intensities for the probe sets. A web application program for visualization and quantitation of regional bias is provided at . CONCLUSION: Researchers should visualize and measure the regional biases and should estimate their impact on gene expression measurements obtained. Here, we (i) introduce pictorial visualizations of the spatial biases; (ii) present for Affymetrix chips a useful resolution of the biases into two components, one related to background, the other to intensity scale factor; (iii) introduce a single parameter to reflect the global bias present across an array. We also examine the pattern distribution of such biases and conclude that algorithms based on smoothing are unlikely to compensate adequately for them
- …