An information theoretic approach to the functional classification of neurons

A population of neurons typically exhibits a broad diversity of responses to sensory inputs. The intuitive notion of functional classification is that cells can be clustered so that most of the diversity is captured in the identity of the clusters rather than by individuals within clusters. We show how this intuition can be made precise using information theory, without any need to introduce a metric on the space of stimuli or responses. Applied to the retinal ganglion cells of the salamander, this approach recovers classical results, but also provides clear evidence for subclasses beyond those identified previously. Further, we find that each of the ganglion cells is functionally unique, and that even within the same subclass only a few spikes are needed to reliably distinguish between cells.Comment: 13 pages, 4 figures. To appear in Advances in Neural Information Processing Systems (NIPS) 1

Into Malbolge

A marine prepares for battle in Iraq and confronts the reality of war. Articles, stories, and other compositions in this archive were written by participants in the Mighty Pen Project. The program, developed by author David L. Robbins, and in partnership with Virginia Commonwealth University and the Virginia War Memorial in Richmond, Virginia, offers veterans and their family members a customized twelve-week writing class, free of charge. The program encourages, supports, and assists participants in sharing their stories and experiences of military experience so both writer and audience may benefit. A platoon brothers just doesn’t fit in the Marines. What are his mates willing to do to help him get out of the service, and maybe save his life

A Peaceful End? Exploring the Correlates of When Terrorist Groups Negotiate

Despite significant advances in the terrorism literature since the September 11th attacks, there remains very little research into the processes by which terrorism might come to a peaceful end. The present study addresses this gap in the literature by investigating politicization, a process by which terrorist organizations negotiate with authorities and the two parties enter a peace agreement or otherwise agree to cease hostilities. The study explores the politicization outcome as predicted by important organizational and behavioral characteristics that prior literature identifies as affecting how terrorist groups end, including group size, organization lifespan, target type for terroristic activities, and the breadth of organizational goals. The key contribution of the current study is a focus on the presence of a non-violent political affiliate (NVPA) within a broader terrorist organization and the role these affiliates play in predicting politicization. Multivariate logistic regression analysis finds strong evidence of a relationship between the presence of a NVPA and politicization, as well as between group size and political cessation of terrorist activities. To elaborate on those findings, a brief case study/typology illustrates these linkages using both historical and contemporary terrorist organizations as examples. I conclude by discussing the role of NVPAs in understanding the terrorist organizational life cycle broadly, as well as directions for future research that extend key themes identified by the current study

Direct spatial-temporal discrimination of modes in a photonic lightwave circuit using photon scanning tunnelling microscopy

Multi-mode photonic lightwave circuits (PLCs) provide new avenues for extending the performance of single mode systems. As an example, they can potentially provide increased bandwidth by multiplexing information into different waveguide modes[1]. For practical applications of multi-mode PLCs to be developed, a measurement technique is required to investigate detailed mode profiles and propagation constants in complex circuits. Photon scanning tunnelling microscopy (PSTM) provides a means of experimentally tracking the femtosecond inter-modal delays observed in PLCs with the ability to discriminate modes by their spatial profiles inside the waveguide

Examining AWB’s market power in the international wheat market

The Australian wheat marketing system has been through a number of stages of deregulation in recent years. However, the AWB still maintains the monopoly selling rights of Australian wheat exports. The AWB and its supporters justify the single desk by arguing that the monopoly power enables them to gain a higher price in the export markets. Opposition to the single desk argues that Australia does not produce enough wheat to influence prices. The objective of this study is to test the market power hypothesis by examining the quantity - price relationship of Australian wheat exports and the stability of this relationship over time using annual data from 1961 to 2000.AWB, single desk, wheat marketing, national competition policy, Agricultural and Food Policy, Crop Production/Industries,

Spontaneous flight activity of mosquitoes (Diptera: Culicidae) infected with filarial nematodes

An acoustic actograph was used to study the influence of filarial worm infection on spontaneous flight activity of host mosquitoes;Aedes aegypti (black-eyed Liverpool strain) were infected with Brugia pahangi to evaluate the effect that filarial larvae developing in flight muscle have on flight activity. Even low numbers of filarial larvae (\u3c10) inhibited flight, especially on days 8-10 postinfection. Parasite intensity was inversely correlated with flight activity and mosquitoes infected with more than 20 larvae could not sustain flight after day 8 PI. However, developing B. pahangi did not influence the circadian activity pattern of Ae. aegypti;Aedes aegypti were also infected with Dirofilaria immitis to determine if larvae developing in Malpighian tubules had any effect on flight activity of host mosquitoes. Flight activity of infected mosquitoes was decreased after day 8 postinfection. Parasite intensity was inversely correlated with flight activity after day 12 postinfection. The circadian pattern of activity of D. immitis-infected mosquitoes was similar to that of uninfected mosquitoes;Spontaneous flight activity of Aedes trivittatus infected with Dirofilaria immitis was studied to determine the effect of parasite infection on flight activity of a natural vector. The activity of mosquitoes infected with low numbers of filarial larvae (1-4) was similar to that of uninfected mosquitoes. However, mosquitoes infected with more than 4 larvae became more active than uninfected mosquitoes 8 days after infection. Infected mosquitoes were active during normal periods of quiescence. Flight activity of mosquitoes infected with more than 4 larvae was suppressed on days 10 and 14 PI, corresponding to the times of greatest disruption of Malpighian tubules by the developing larvae

Graptolite Faunas of the Northern Part of the Taconic Area

Guidebook for the fifty-first annual meeting of the New England Intercollegiate Geological Conference: Stratigraphy and structure of west central Vermont and adjacent New York, Rutland, Vermont October 17-18, 1959: Trip G-