Calculating the output distribution of stack filters that are erosion-dilation cascades, in particular LULU-filters

Original article available at http://arxiv.org/ENGLISH ABSTRACT: Two procedures to compute the output distribution 0S of certain stack filters S (so called erosion-dilation cascades) are given. One rests on the disjunctive normal form of S and also yields the rank selection probabilities. The other is based on inclusion-exclusion and e.g. yields 0S for some important LULU-operators S. Properties of 0S can be used to characterize smoothing properties.Preprin

The time dimension of neural network models

This review attempts to provide an insightful perspective on the role of time within neural network models and the use of neural networks for problems involving time. The most commonly used neural network models are defined and explained giving mention to important technical issues but avoiding great detail. The relationship between recurrent and feedforward networks is emphasised, along with the distinctions in their practical and theoretical abilities. Some practical examples are discussed to illustrate the major issues concerning the application of neural networks to data with various types of temporal structure, and finally some highlights of current research on the more difficult types of problems are presented

Tracking Cooper Pairs in a Cuprate Superconductor by Ultrafast Angle-Resolved Photoemission

In high-temperature superconductivity, the process that leads to the formation of Cooper pairs, the fundamental charge carriers in any superconductor, remains mysterious. We use a femtosecond laser pump pulse to perturb superconducting Bi2Sr2CaCu2O8+{\delta}, and study subsequent dynamics using time- and angle-resolved photoemission and infrared reflectivity probes. Gap and quasiparticle population dynamics reveal marked dependencies on both excitation density and crystal momentum. Close to the d-wave nodes, the superconducting gap is sensitive to the pump intensity and Cooper pairs recombine slowly. Far from the nodes pumping affects the gap only weakly and recombination processes are faster. These results demonstrate a new window into the dynamical processes that govern quasiparticle recombination and gap formation in cuprates.Comment: 22 pages, 9 figure

Campo ambiental midiatizado: a vigilância colaborativa da Amazônia

RESUMO A manifestação do complexo processo de midiatização potencializou-se nas últimas décadas. Nesse cenário, os campos sociais se apropriaram de mecanismos discursivos do campo midiático, o que possibilitou a emergência de um espaço para a reflexão, vigilância e monitoramento de questões globais como os problemas ambientais. O objetivo desse artigo é mostrar como ocorrem imbricações entre os campos midiático e ambiental a partir da intensificação do processo de midiatização através do qual distintos cidadãos constroem o InfoAmazonia, banco de dados sobre as problemáticas da Amazônia. Para tanto, o trabalho se assenta metodologicamente na perspectiva da análise semiológica para identificar o contrato de leitura (VERÓN, 2004) construído pela plataforma. A investigação aponta que este enunciador se caracteriza pela legitimação de um sujeito protagonista, cogestor na vigilância colaborativa da Amazônia. Palavras-chave: midiatização; campo ambiental; contrato de leitura   RESUMEN La manifestación del complejo proceso de mediatización se intensifica en las últimas décadas. En este escenario, los mecanismos discursivos del campo de los medios son apropiados por los campos sociales, lo que permitió el surgimento de un espacio de reflexión, vigilancia y rastreo de temas globales como los problemas ambientales. Lo objetivo deste artículo és mostrar cómo se producen solapamientos entre los campos mediático e ambiental gracias a intensificación del proceso de mediatizatión, además analizar y describir el contracto de lectura que emerge del proceso de construcción de InfoAmazonia, base de datos sobre los problemas de la Amazonía. Por lo tanto, el trabajo se basa metodológicamente en la perspectiva semiológica para identificar el contrato de lectura (VERÓN, 2004) de la plataforma. La investigación muestra que este enunciador se caracteriza por la legitimación de un actor protagonista, cogestor en la vigilancia de colaboración de la Amazonia.   Palabras clave: mediatización; campo ambiental; contracto de lectura   ABSTRACT The manifestation of the complex process of mediatization is leveraged in recent decades. Under this scenario, the social fields appropriated discursive mechanisms of the media field, which allowed the emergence of a space for reflection, surveillance and monitoring of global issues such as environmental problems. This research aims to show how they occur overlaps between the media and environmental fields with the intensification of mediatization, besides analyze and describe the reading agreement emerging from the construction process of InfoAmazonia, a database about the problems of the Amazon. Therefore, the work is methodologically based on semiological perspective to identify the platform reading contract (VERÓN, 2004). Research shows that this annunciator is characterized by the legitimation of a subject protagonist, who helps oversee the collaborative surveillance of the Amazon.   Keywords: mediatization; environmental field; reading agreement

A Quantitative Analysis of Flight Feather Replacement in the Moustached Tree Swift Hemiprocne mystacea, a Tropical Aerial Forager

The functional life span of feathers is always much less than the potential life span of birds, so feathers must be renewed regularly. But feather renewal entails important energetic, time and performance costs that must be integrated into the annual cycle. Across species the time required to replace flight feather increases disproportionately with body size, resulting in complex, multiple waves of feather replacement in the primaries of many large birds. We describe the rules of flight feather replacement for Hemiprocne mystacea, a small, 60g tree swift from the New Guinea region. This species breeds and molts in all months of the year, and flight feather molt occurs during breeding in some individuals. H. mystacea is one to be the smallest species for which stepwise replacement of the primaries and secondaries has been documented; yet, primary replacement is extremely slow in this aerial forager, requiring more than 300 days if molt is not interrupted. We used growth bands to show that primaries grow at an average rate of 2.86 mm/d. The 10 primaries are a single molt series, while the 11 secondaries and five rectrices are each broken into two molt series. In large birds stepwise replacement of the primaries serves to increase the rate of primary replacement while minimizing gaps in the wing. But stepwise replacement of the wing quills in H. mystacea proceeds so slowly that it may be a consequence of the ontogeny of stepwise molting, rather than an adaptation, because the average number of growing primaries is probably lower than 1.14 feathers per wing

Transmission in NFS/N mice of the heritable spongiform encephalopathy associated with the gray tremor mutation.

It has been shown that the autosomal recessive mutation, gray tremor (gt) was associated in the homozygous state (gt/gt) with a rapidly fatal spongiform encephalopathy. Heterozygotes (+/gt) developed mild asymptomatic spongiform brain lesions as did recipient inbred mice inoculated with gt/gt brain homogenates, some of whom also showed behavioral abnormalities [Sidman, R. L., Kinney, H. C. & Sweet, H. O. (1985) Proc. Natl. Acad. Sci. USA 82, 253-257]. In these studies, inbred NFS/N mice inoculated intracerebrally at birth or as adults with gt/gt or first passage gt brain homogenates developed a progressive disease characterized by tremor, ataxia, and spasticity. The symptoms were milder and more slowly progressive than in the gt/gt homozygote, in the paralytic syndrome that followed neonatal inoculation of NFS/N mice with a wild murine leukemia virus (Cas-Br-M MuLV), or in the rapidly progressive ataxia and terminal bradykinesia that followed scrapie inoculation of NFS/N mice. The noninflammatory spongiform encephalopathy in affected NFS/N mice resembled that observed in gt/gt homozygotes, +/gt heterozygotes, and asymptomatic recipient inbred mice inoculated with gt/gt brain homogenates. Neither infectious MuLV nor MuLV proteins were detected in gt/gt brain homogenates or in affected recipient mouse brains. Scrapie-associated fibrils, readily identifiable in subcellular fractions of brains from scrapie-inoculated NFS/N mice, were not detected in similar brain fractions from NFS/N mice inoculated with gt brain homogenates. These results confirm and extend the suggestion that gt spongiform encephalopathy has both heritable and transmissible properties. Moreover, the transmissible agent of gt disease differs from both Cas-Br-M MuLV and scrapie in its disease-inducing properties in NFS/N mice. The capacity of NFS/N mice to express transmitted gt encephalopathy as clinical disease, to rapidly express Cas-Br-M MuLV spongiform encephalomyelopathy, and to develop mouse-adapted scrapie after a very short incubation time suggest a distinct sensitivity of NFS/N mice to transmissible spongiform encephalopathy

Web-Based Geologic Maps, Databases, and HTML Pages for Marion County, Indiana

This poster was presented at the 2011 meeting of the Indiana Academy of Science, 126th Annual Academy Meeting, March 4-5, 2011, Indianapolis, Indiana.The Indiana Geological Survey (IGS) has created an internet map server for Marion County in central Indiana. The site provides detailed geologic information needed to address environmental issues, resource management issues, and land-use conflicts related to a growing population. Marion County is the location of Indianapolis, the state capital and largest city. The IGS anticipates that the Web site will be widely used by the general public, industry, and government entities concerned about the geology, groundwater, and other natural resources. The Marion County Web site links an Internet map server (IMS) and database to provide a portal to the IGS‘s enterprise geodatabases, which allow users to efficiently create, manage, update, and distribute maps and data. The IMS site retrieves maps of bedrock and surficial geology completed during earlier IGS mapping projects. Hydrogeology, infrastructure, and imagery map layers are also included. Database information includes lithologic information (iLITH) compiled from water-well records stored in the Indiana Department of Natural Resources, Division of Water archives and natural gamma-ray geophysical log data, stratigraphic test hole data, and petroleum well-record data from the IGS. Currently, the following products are being prepared: (1) illustrated Web pages discussing the surficial geology, bedrock geology, and bedrock topography; (2) illustrated Web pages discussing digital elevation model terrain, gamma-ray log, iLITH, and clay thickness data sets; (3) online glossary; and (4) metadata for the map layers. The development of the Web site is funded by the IGS and the Great Lakes Geologic Mapping Coalition.Great Lakes Geologic Mapping Coalitio

Climatic patterns in the establishment of wintering areas by North American migratory birds

Long-distance migration in birds is relatively well studied in nature; however, one aspect of this phenomenon that remains poorly understood is the pattern of distribution presented by species during arrival to and establishment of wintering areas. Some studies suggest that the selection of areas in winter is somehow determined by climate, given its influence on both the distribution of bird species and their resources. We analyzed whether different migrant passerine species of North America present climatic preferences during arrival to and departure from their wintering areas. We used ecological niche modeling to generate monthly potential climatic distributions for 13 migratory bird species during the winter season by combining the locations recorded per month with four environmental layers. We calculated monthly coefficients of climate variation and then compared two GLM (generalized linear models), evaluated with the AIC (Akaike information criterion), to describe how these coefficients varied over the course of the season, as a measure of the patterns of establishment in the wintering areas. For 11 species, the sites show nonlinear patterns of variation in climatic preferences, with low coefficients of variation at the beginning and end of the season and higher values found in the intermediate months. The remaining two species analyzed showed a different climatic pattern of selective establishment of wintering areas, probably due to taxonomic discrepancy, which would affect their modeled winter distribution. Patterns of establishment of wintering areas in the species showed a climatic preference at the macroscale, suggesting that individuals of several species actively select wintering areas that meet specific climatic conditions. This probably gives them an advantage over the winter and during the return to breeding areas. As these areas become full of migrants, alternative suboptimal sites are occupied. Nonrandom winter area selection may also have consequences for the conservation of migratory bird species, particularly under a scenario of climate change

The flight feather moult pattern of the bearded vulture (Gypaetus barbatus).

Moult is an extremely time-consuming and energy-demanding task for large birds. In addition, there is a trade-off between the time devoted to moulting and that invested in other activities such as breeding and/or territory exploration. Moreover, it takes a long time to grow a long feather in large birds, and large birds that need to fly while moulting cannot tolerate large gaps in the wing, but only one or two simultaneously growing feathers. As a consequence, large birds take several years to complete a full moult cycle, and they resume the moult process during suboptimal conditions. A clear example of this pattern is the Bearded Vulture (Gypaetus barbatus), which needs 2-3 years for changing all flight feathers. Here we describe the sequence, extent, and timing of moult of 124 Bearded Vultures in detail for the first time. We found that extent and timing of flight feather moult was different between age classes. Subadults (from 3rd to 5th calendar year) started moult, on average, in early March, whereas adults only started moult, on average, in late April, possibly due to breeding requirements. Second calendar year individuals delayed onset of moult until the middle of May. In general, the moult lasted until November, and although adults started to moult later than subadults, they moulted more feathers. Subadults needed 3 years for moulting all flight feathers, whereas adults normally completed it in 2 years