High resolution, high capacity, spatial specificity in perceptual learning.

Research of perceptual learning has received significant interest due to findings that training on perceptual tasks can yield learning effects that are specific to the stimulus features of that task. However, recent studies have demonstrated that while training a single stimulus at a single location can yield a high-degree of stimulus specificity, training multiple features, or at multiple locations can reveal a broad transfer of learning to untrained features or stimulus locations. We devised a high resolution, high capacity, perceptual learning procedure with the goal of testing whether spatial specificity can be found in cases where observers are highly trained to discriminate stimuli in many different locations in the visual field. We found a surprising degree of location specific learning, where performance was significantly better when target stimuli were presented at 1 of the 24 trained locations compared to when they were placed in 1 of the 12 untrained locations. This result is particularly impressive given that untrained locations were within a couple degrees of visual angle of those that were trained. Given the large number of trained locations, the fact that the trained and untrained locations were interspersed, and the high-degree of spatial precision of the learning, we suggest that these results are difficult to account for using attention or decision strategies and instead suggest that learning may have taken place for each location separately in retinotopically organized visual cortex

High throughput screening for identification of mycolactone targets : Relations between M. ulcerans and nervous system

Buruli ulcer is an infectious disease transmitted by arthropod vectors harboring Mycobacterium ulcerans, a mycobacterium which belong to the same family of bacteria causing tuberculosis and leprosy. The infection causes painless swelling and severe skin lesions. One key feature of M. ulcerans bacterium is its ability to secrete a necrotic toxin, the mycolactone within small lipophilic vesicles, which are critical for the bacterial induced cytotoxicity. The biological knowledge as well as the preventive and therapeutic means for this invalidating disease is still very limited.   Our first approach was to investigate whether the mycolactone toxin could be involved in the neutralization of pain by acting directly on the peripheral nervous system without causing destruction of nervous fibers. By use of live time fluorescence microscopy and appropriate markers, we showed that the addition of toxin at sub-toxic dose provokes modification of ionic currents of neuron cells. Based on this ability of the toxin, a molecular high throughput methodology was developed for the screening of a genome wide siRNA library and small molecules inhibitors to enable the search of the cellular targets for the toxin. The cell-based assay relies on automated confocal microscopy on macrophages coupled with dedicated image analysis. These two screening allowed us to identify a putative toxin target, and a toxin inhibitor. A binding assay confirmed that the putative target is a receptor of the toxin. Together these results allowed us to build a potential signaling pathway activated by the mycolactone and implicated in ionic channel activities.   The second approach was to confirm this model in the mouse model of M. ulcerans infection and its role in the hypoesthesia of the lesions. Toxin inhibitor, daily administered to mice, which were experimentally infected by M. ulcerans, conducted to the absence of the hypoesthesia of the lesions. Furthermore, a histological study of neuronal fibers did not show a destruction of neuronal cells. Moreover, in vitro studies have showed that M. ulcerans are able to colonize neuronal cells. Then, these results suggested that the hypoesthesia of the M. ulcerans lesions could be caused by a non-destructive process of nervous cells.

An inexpensive nonlinear medium for intense ultrabroadband pulse characterization

The ability of pellets made up of compressed iron iodate nanocrystals to frequency-double the whole visible spectrum is demonstrated. We suggest their use for complete characterization of intense ultrabroadband laser pulse

Is M. ulcerans able to colonize neuronal cells?

Buruli ulcer, or Mycobacterium ulcerans infection, is an emerging disease, principally diagnosed in humid tropical countries and inducing large skin ulcers. These lesions are painless, a distinct feature that suggests that the mycolactone toxin and/or M. ulcerans impedes the signal transmission by the nervous system. In this context, the aim of this work was to study the interaction between M. ulcerans and neuronal cells by using in vitro and in vivo models. We showed that a virulent strain of M. ulcerans is able to enter into neurons cultivated from neonatal rat hippocampus. On the contrary, this phenomenon was less observed with a mycolactone-deficient strain. To support these data, we analysed nerve fibres from mouse-infected tissues and few bacilli were found in close contact with nerve fibres. The invasion process established by M. ulcerans to colonize the nervous system remains uncharacterised, but we hypothesise that this ability could be involved in the painless of the M. ulcerans infection

Surfacing Small Worlds through Data-In-Place

We present findings from a five-week deployment of voting technologies in a city neighbourhood. Drawing on Marres’ (2012) work on material participation and Massey’s (2005) conceptualisation of space as dynamic, we designed the deployment such that the technologies (which were situated in residents’ homes, on the street, and available online) would work in concert, cutting across the neighbourhood to make visible, juxtapose and draw together the different ‘small worlds’ within it. We demonstrate how the material infrastructure of the voting devices set in motion particular processes and interpretations of participation, putting data in place in a way that had ramifications for the recognition of heterogeneity. We conclude that redistributing participation means not only opening up access, so that everyone can participate, or even providing a multitude of voting channels, so that people can participate in different ways. Rather, it means making visible multiplicity, challenging notions of similarity, and showing how difference may be productive

Interacting with eHealth - Towards grand challenges for HCI

While health records are increasingly stored electronically, we, as citizens, have little access to this data about ourselves. We are not used to thinking of these official records either as ours or as useful to us. We increasingly turn to the Web, however, to query any ache, pain or health goal we may have before consulting with health care professionals. Likewise, for proactive health care such as nutrition or fitness, or to find fellow-sufferers for post diagnosis support, we turn to online resources. There is a potential disconnect between points at which professional and lay eHealth data and resources intersect for preventative or proactive health care. Such gaps in information sharing may have direct impact on practices we decide to take up, the care we seek, or the support professionals offer. In this panel, we consider several places within proactive, preventative health care in particular HCI has a role towards enhancing health knowledge discovery and health support interaction. Our goal is to demonstrate how now is the time for eHealth to come to the forefront of the HCI research agenda

Tectonic controls on nearshore sediment accumulation and submarine canyon morphology offshore La Jolla, Southern California

CHIRP seismic and swath bathymetry data acquired offshore La Jolla, California provide an unprecedented three-dimensional view of the La Jolla and Scripps submarine canyons. Shore-parallel patterns of tectonic deformation appear to control nearshore sediment thickness and distribution around the canyons. These shore-parallel patterns allow the impact of local tectonic deformation to be separated from the influence of eustatic sea-level fluctuations. Based on stratal geometry and acoustic character, we identify a prominent angular unconformity inferred to be the transgressive surface and three sedimentary sequences: an acoustically laminated estuarine unit deposited during early transgression, an infilling or “healing-phase” unit formed during the transgression, and an upper transparent unit. Beneath the transgressive surface, steeply dipping reflectors with several dip reversals record faulting and folding along the La Jolla margin. Scripps Canyon is located at the crest of an antiform, where the rocks are fractured and more susceptible to erosion. La Jolla Canyon is located along the northern strand of the Rose Canyon Fault Zone, which separates Cretaceous lithified rocks to the south from poorly cemented Eocene sands and gravels to the north. Isopach and structure contour maps of the three sedimentary units reveal how their thicknesses and spatial distributions relate to regional tectonic deformation. For example, the estuarine unit is predominantly deposited along the edges of the canyons in paleotopographic lows that may have been inlets along barrier beaches during the Holocene sea-level rise. The distribution of the infilling unit is controlled by pre-existing relief that records tectonic deformation and erosional processes. The thickness and distribution of the upper transparent unit are controlled by long-wavelength, tectonically induced relief on the transgressive surface and hydrodynamics

Prospecting environmental mycobacteria: combined molecular approaches reveal unprecedented diversity

Background: Environmental mycobacteria (EM) include species commonly found in various terrestrial and aquatic environments, encompassing animal and human pathogens in addition to saprophytes. Approximately 150 EM species can be separated into fast and slow growers based on sequence and copy number differences of their 16S rRNA genes. Cultivation methods are not appropriate for diversity studies; few studies have investigated EM diversity in soil despite their importance as potential reservoirs of pathogens and their hypothesized role in masking or blocking M. bovis BCG vaccine. Methods: We report here the development, optimization and validation of molecular assays targeting the 16S rRNA gene to assess diversity and prevalence of fast and slow growing EM in representative soils from semi tropical and temperate areas. New primer sets were designed also to target uniquely slow growing mycobacteria and used with PCR-DGGE, tag-encoded Titanium amplicon pyrosequencing and quantitative PCR. Results: PCR-DGGE and pyrosequencing provided a consensus of EM diversity; for example, a high abundance of pyrosequencing reads and DGGE bands corresponded to M. moriokaense, M. colombiense and M. riyadhense. As expected pyrosequencing provided more comprehensive information; additional prevalent species included M. chlorophenolicum, M. neglectum, M. gordonae, M. aemonae. Prevalence of the total Mycobacterium genus in the soil samples ranged from 2.3×107 to 2.7×108 gene targets g−1; slow growers prevalence from 2.9×105 to 1.2×107 cells g−1. Conclusions: This combined molecular approach enabled an unprecedented qualitative and quantitative assessment of EM across soil samples. Good concordance was found between methods and the bioinformatics analysis was validated by random resampling. Sequences from most pathogenic groups associated with slow growth were identified in extenso in all soils tested with a specific assay, allowing to unmask them from the Mycobacterium whole genus, in which, as minority members, they would have remained undetected

A linguistic approach to assess the dynamics of design team preference in concept selection

This paper addresses the problem of describing the decision-making process of a committee of engineers based upon their verbalized linguistic appraisals of alternatives. First, we show a way to model an individual’s evaluation of an alternative through natural language based on the Systemic-Functional Linguistics system of APPRAISAL. The linguistic model accounts for both the degree of intensity and the uncertainty of expressed evaluations. Second, this multi-dimensional linguistic model is converted into a scalar to represent the degree of intensity and a probability distribution function for the stated evaluation. Finally, we present a Markovian model to calculate the time-varying change in preferential probability, the probability that an alternative is the most preferred alternative. We further demonstrate how preferential probability toward attributes of alternatives correspond to preferential probability toward alternatives. We illustrate the method on two case studies to highlight the time-variant dynamics of preferences toward alternatives and attributes. This research contributes to process tracing in descriptive decision science to understand how engineers actually take decisions.National Science Foundation (U.S.) (Award CMMI-0900255