Trajectory Mapping ("TM''): A New Non-Metric Scaling Technique

Trajectory Mapping "TM'' is a new scaling technique designed to recover the parameterizations, axes, and paths used to traverse a feature space. Unlike Multidimensional Scaling (MDS), there is no assumption that the space is homogenous or metric. Although some metric ordering information is obtained with TM, the main output is the feature parameterizations that partition the given domain of object samples into different categories. Following an introductory example, the technique is further illustrated using first a set of colors and then a collection of textures taken from Brodatz (1966)

Optimum flux-detection in the absence of a priori knowledge about the signal

Detection systems based on photon counting have to discriminate between two types of fluctuations in the photon count: those resulting from statistical fluctuations (=noise) and those caused by changes in the radiance set by the source (=signal). In contrast with earlier studies on ways of discriminating noise from signal changes, no specific assumptions are made about the source. An optimal discrimination-method has been developed for a detector that has no prior information about the mean of the Poisson distribution that describes its input signal. Because the detector has no prior information at its disposal it has to assume an a priori probability for the mean in a unique and objective way and it has to estimate the actual mean using Bayes rule of inference. This new discrimination-method is discussed in the context of signal processing in the visual system, but is generally applicable in all systems where photon-noise is important

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In our study, for a small number of antonyms, we investigate whether they are cross-modally or ideaesthetically related to the space of colors. We analyze the affinities of seven antonyms (cold-hot, dull-radiant, dead-vivid, soft-hard, transparent-chalky, dry-wet, and acid-treacly) and their intermediate connotations (cool-warm, matt-shiny, numb-lively, mellow-firm, semi-transparent-opaque, semi-dry-moist, and sour-sweet) as a function of color. We find that some antonyms relate to chromatic dimensions, others to achromatic ones. The cold-hot antonym proves to be the most salient dimension. The dry-wet dimension coincides with the cold-hot dimension, with dry corresponding to hot and wet to cold. The acid-treacly dimension proves to be transversal to the cold-hot dimension; hence, the pairs mutually span the chromatic domain. The cold-hot and acid-treacly antonyms perhaps recall Hering's opponent color system. The dull-radiant, transparent-chalky, and dead-vivid pairs depend little upon chromaticity. Of all seven antonyms, only the soft-hard one turns out to be independent of the chromatic structure

Efflux transport of nicotine, cotinine and trans-3 '-hydroxycotinine glucuronides by human hepatic transporters

Nicotine is the addiction causing alkaloid in tobacco, and it is used in smoking cessation therapies. Although the metabolic pathways of nicotine are well known and mainly occur in the liver, the transport of nicotine and its metabolites is poorly characterized. The highly hydrophilic nature and urinary excretion of nicotine glucuronide metabolites indicate that hepatic basolateral efflux transporters mediate their excretion. We aimed here to find the transporters responsible for the hepatic excretion of nicotine, cotinine and trans-3 '-hydroxycotinine (OH-cotinine) glucuronides. To this end, we tested their transport by multidrug resistance-associated proteins 1 (MRP1, ABCC1) and MRP3-6 (ABCC3-6), which are located on the basolateral membranes of hepatocytes, as well as MRP2 (ABCC2), breast cancer resistance protein (BCRP, ABCG2) and multidrug resistance protein 1 (MDR1, P-gp, ABCB1) that are expressed in the apical membranes of these cells. ATP-dependent transport of these glucuronides was evaluated in inside-out membrane vesicles expressing the transporter of interest. In addition, potential interactions of both the glucuronides and parent compounds with selected transporters were tested by inhibition assays. Considerable ATP-dependent transport was observed only for OH-cotinine glucuronide by MRP3. The kinetics of this transport activity was characterized, resulting in an estimated K-m value of 895 mu mol/L. No significant transport was found for nicotine or cotinine glucuronides by any of the tested transporters at either 5 or 50 mu mol/L substrate concentration. Furthermore, neither nicotine, cotinine nor OH-cotinine inhibited MRP2-4, BCRP or MDR1. In this study, we directly examined, for the first time, efflux transport of the three hydrophilic nicotine glucuronide metabolites by the major human hepatic efflux transporters. Despite multiple transporters studied here, our results indicate that an unknown transporter may be responsible for the hepatic excretion of nicotine and cotinine glucuronides.Peer reviewe

From science to practice: Bringing innovations to agronomy and forestry

The challenge of the work presented here is to make innovative research output in the agronomy and forestry domain accessible to end-users, so that it can be practically applied. We have developed an approach that consists of three key-elements: an ontology with domain knowledge, a set of documents that have been annotated and meta-annotated, and a system (ask-Valerie) that is based on a dialogue to represent the interaction between end user and system.<br/> We show that the dialogue-metaphor is a good way of modelling the interaction between user and system. The system helps the user in formulating his question and in answering it in a useful way. Meta-annotations of key-paragraphs in the document-base turn out to be relevant in assessing in one glance what the content of a document is. <br/> End-users are very enthusiastic about the possibilities that ask-Valerie offers them in translating scientific results to their own situation

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<p>Do generic observers in their free-style viewing of postcard-size pictures have a preference for spe­cific modes of perspective rendering? This most likely depends upon the phrasing of the question. Here we consider the feeling of ‘presence’: does the observer experience a sense of being ‘immersed in the scene’? We had 40 Italian naïve participants and 19 British art students rate three types of rendering of ten ‘typical holiday pictures’. All pictures represented 130° over the width of the picture. They were rendered in linear perspective, Hauck maps, and Postel maps. The results are clearcut. About a quarter of the participants prefer linear perspective, whereas the Hauck map is preferred by more than half of the participants. Naïve observers and art students agree. Architectural scenes are somewhat more likely to be preferred in perspective. Preferences are not randomly distributed, but participants have remarkable idiosyncratic affinities, a small group for perspective projection, a larger group for the Hauck map. Such facts might find application in the viewing of photographs on hand­held electronic display devices.</p

Особенности формирования системы резервов в Украине

Проблемы формирования системы резервов на всех уровнях, является важным для экономической устойчивости государства. Особенности формирования системы резервов по ее уровням и подуровням, группировка и характеристика факторов резервов дают возможность прогнозировать объемы самих резервов и выявлять их дефицит.Проблеми формування системи резервів на всіх рівнях, є важливим для економічної стійкості держави. Особливості формування системи резервів по її рівнях і підрівнях, угрупування і характеристика чинників резервів дають можливість прогнозувати об'єми самих резервів і виявляти їх дефіцит.Problems of forming of the system of backlogs at all levels, is important for economic stability of the state. The features of forming of the system of backlogs on its levels and sublevels, groupment and description of factors of backlogs enable to forecast the volumes of backlogs and expose their deficit

The Phenomenology of the Invisible: From Visual Syntax to “Shape from Shapes”

Nous abordons ici l’étude de la phénoménologie des objets visuels à partir de comptes rendus verbaux, de réponses à des questions ou de descriptions spontanées, ainsi que d’associations libres. Nous demandons même parfois aux sujets de réaliser de simples croquis. Cet éventail de méthodes permet de sonder la structure profonde de la conscience visuelle. Celle-ci est avant tout révélée par ce qui n’est pas spontanément mentionné par des qualités accidentelles ou encore par des changements induits lors de variations ou ajouts mineurs. Nous avons trouvé une concordance remarquable parmi un grand nombre de participants. Ceci démonte que les comptes-rendus verbaux permettent d’explorer puissamment la structure de la conscience visuelle. Tout comme le langage, les « objets visuels simples » ont des racines profondes dans la conscience. Ces fondations « invisibles » servent à définir des figures simples, un « carré » par exemple, comme des objets prototypiques et uniques. La nature des « objets visuels » implique ainsi l’existence d’un « vaste domaine invisible ». Sans une telle prise en compte, la compréhension correcte de la nature de l’objet visuel n’est pas possible. Cette découverte devrait permettre de mener à une théorie de la syntaxe formelle des formes visuelles fondamentales.Here, we address the phenomenology of visual objects, using verbal reports, spontaneous descriptions, answers to questions and responses to suggestions, as well as free associations. We occasionally ask for simple sketches. Such methods allow probing of the deep structure of visual awareness. This is above all revealed by what is not spontaneously mentioned, or is only mentioned by way of incidental properties. It is also disclosed by changes induced by minor variations or additions. We find remarkable agreement over a large number of participants. Thus verbal reports are a powerful probe of visual structure. Similarly to language, ``simple visual objects’’ have deep roots in subsidiary awareness. These ``invisible’’ foundations serve to define simple figures, like a ``square’’, as unique, prototypical objects. The nature of ``visual objects’’ thus involves an extensive ``invisible’’ realm. Without taking this into account, a proper understanding of the nature of the visual object is not possible. Finally, this should lead to a formal syntactical theory of basic visual shapes

Transmembrane Domain Single-Nucleotide Polymorphisms Impair Expression and Transport Activity of ABC Transporter ABCG2

To study the function and expression of nine naturally occurring single-nucleotide polymorphisms (G406R, F431L, S441N, P480L, F489L, M515R, L525R, A528T and T542A) that are predicted to reside in the transmembrane regions of the ABC transporter ABCG2. The transport activity of the variants was tested in inside-out membrane vesicles from Sf9 insect and human derived HEK293 cells overexpressing ABCG2. Lucifer Yellow and estrone sulfate were used as probe substrates of activity. The expression levels and cellular localization of the variants was compared to the wild-type ABCG2 by western blotting and immunofluorescence microscopy. All studied variants of ABCG2 displayed markedly decreased transport in both Sf9-ABCG2 and HEK293-ABCG2 vesicles. Impaired transport could be explained for some variants by altered expression levels and cellular localization. Moreover, the destructive effect on transport activity of variants G406R, P480L, M515R and T542A is, to our knowledge, reported for the first time. These results indicate that the transmembrane region of ABCG2 is sensitive to amino acid substitution and that patients harboring these ABCG2 variant forms could suffer from unexpected pharmacokinetic events of ABCG2 substrate drugs or have an increased risk for diseases such as gout where ABCG2 is implicated.Peer reviewe

measures of pragnanz

Summary Prägnanz was suggested by Max Wertheimer in the 1920s as subsuming all "Laws of Gestalt" as they apply to visual awareness. Thus, it assumes a prominent position in any account of Gestalt phenomena. From a phenomenological perspective, some visual stimuli evidently "have more Prägnanz" than others, so Prägnanz seems to be an intensive quality. Here, we investigate the intricacies that need to be faced on the way to a definition of formal scales. Such measures naturally depend both upon the stimulus and upon the observer. Structural complexity bottlenecks of visual systems play a role, as well as the relevance to biological fitness, that is the affinity to the optical user interface. This positions the notion of Prägnanz squarely within the realm of biology. Indeed, the familiar "releasers" of ethology are singular cases of extremely high Prägnanz