19 research outputs found

    Prostate Cancer Experimental Therapeutics

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    Definitions of state variables and state space for brain–computer interface: Part 2. Extraction and classification of feature vectors

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    The hypothesis is proposed that the central dynamics of the action–perception cycle has five steps: emergence from an existing macroscopic brain state of a pattern that predicts a future goal state; selection of a mesoscopic frame for action control; execution of a limb trajectory by microscopic spike activity; modification of microscopic cortical spike activity by sensory inputs; construction of mesoscopic perceptual patterns; and integration of a new macroscopic brain state. The basis is the circular causality between microscopic entities (neurons) and the mesoscopic and macroscopic entities (populations) self-organized by axosynaptic interactions. Self-organization of neural activity is bidirectional in all cortices. Upwardly the organization of mesoscopic percepts from microscopic spike input predominates in primary sensory areas. Downwardly the organization of spike outputs that direct specific limb movements is by mesoscopic fields constituting plans to achieve predicted goals. The mesoscopic fields in sensory and motor cortices emerge as frames within macroscopic activity. Part 1 describes the action–perception cycle and its derivative reflex arc qualitatively. Part 2 describes the perceptual limb of the arc from microscopic MSA to mesoscopic wave packets, and from these to macroscopic EEG and global ECoG fields that express experience-dependent knowledge in successive states. These macroscopic states are conceived to embed and control mesoscopic frames in premotor and motor cortices that are observed in local ECoG and LFP of frontoparietal areas. The fields sampled by ECoG and LFP are conceived as local patterns of neural activity in which trajectories of multiple spike activities (MSA) emerge that control limb movements. Mesoscopic frames are located by use of the analytic signal from the Hilbert transform after band pass filtering. The state variables in frames are measured to construct feature vectors by which to describe and classify frame patterns. Evidence is cited to justify use of linear analysis. The aim of the review is to enable researchers to conceive and identify goal-oriented states in brain activity for use as commands, in order to relegate the details of execution to adaptive control devices outside the brain

    Urogenital tuberculosis: patient classification in seven different groups according to clinical and radiological presentation

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    PURPOSE: To describe and classify 80 cases of urogenital tuberculosis in seven groups of similar clinical and radiological presentation. MATERIALS AND METHODS: 80 patients (56 males, 70%; median age 34 years; age range 12 to 75) with urogenital tuberculosis were retrospectively reviewed. The patients were divided in seven groups: 1) Bilateral parenchymatous renal lesions; 2) No or minimal changes on radiographic examination; 3) Unilateral renal tuberculosis; 4) Contracted bladder; 5) Contracted bladder with renal failure; 6) Tuberculosis on a transplanted kidney; 7) Isolated genital tuberculosis. RESULTS: 1) Seven (8.8%) patients had multiple bilateral parenchymatous renal lesions with fever and malaise, characteristic of miliary tuberculosis. Three of these patients had AIDS. 2) Six (7.5%) cases had an early diagnosis, with minimal or no radiographic lesions. Two did not have any urologic symptoms. 3) Twelve (15%) patients had unilateral renal tuberculosis with partial (1 case) or total non-function kidney. 4) Thirty-seven (46.3%) patients had contracted bladder associated with unilateral partial (1 case) or total non-function kidney. 5) Ten (12.5%) patients had end stage renal disease due to tuberculosis with contracted bladder. 6) Four (5.0%) patients had tuberculosis on a transplanted kidney, with graft loss in half the cases. 7) Four (5.0%) patients had prostate or epididymis tuberculosis without associated renal lesion. CONCLUSIONS: Urogenital tuberculosis is a destructive disease of the urogenital tract with variable clinical and radiographic presentation. A classification according to similar patterns correlating with disease stage is feasible although early diagnosis is the only prevention of the most severe forms

    Lactifluus piperatus (Russulales, Basidiomycota) and allied species in Western Europe and a preliminary overview of the group worldwide

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    The large, white milkcaps of Lactifluus section Piperati are well known in the northern hemisphere. Historically, there was extensive debate about the number of European representatives and the diagnostic characteristics that delimit the species. Combining a morphological approach with a phylogenetic study, we aimed to resolve the problems in this section in Europe. Secondly, a molecular analysis of worldwide representatives of Lactifluus section Piperati was carried out, to verify whether there is intercontinental conspecificity. We compared nuclear ITS and LSU rDNA, nuclear protein-coding rpb2 and mitochondrial protein-coding atp6 genealogies to delimit species, using a concatenation of genes, along with Bayesian species delimitation for the European dataset. The phylogenetic analyses show the existence of two species in Europe: Lactifluus piperatus and Lactifluus glaucescens. Morphologically, the frequently used characteristics of the colouration of the latex and the macrochemical reactions of latex and context appear not to be useful as diagnostic characteristics to discriminate the species, but the microscopical characters of the pileipellis are informative. The preliminary overview of the section worldwide shows that it comprises at least 10 possible species divided over three clades, and that there is no intercontinental conspecificity

    Definitions of state variables and state space for brain-computer interface: Part 1. Multiple hierarchical levels of brain function

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    Neocortical state variables are defined and evaluated at three levels: microscopic using multiple spike activity (MSA), mesoscopic using local field potentials (LFP) and electrocorticograms (ECoG), and macroscopic using electroencephalograms (EEG) and brain imaging. Transactions between levels occur in all areas of cortex, upwardly by integration (abstraction, generalization) and downwardly by differentiation (speciation). The levels are joined by circular causality: microscopic activity upwardly creates mesoscopic order parameters, which downwardly constrain the microscopic activity that creates them. Integration dominates in sensory cortices. Microscopic activity evoked by receptor input in sensation induces emergence of mesoscopic activity in perception, followed by integration of perceptual activity into macroscopic activity in concept formation. The reverse process dominates in motor cortices, where the macroscopic activity embodying the concepts supports predictions of future states as goals. These macroscopic states are conceived to order mesoscopic activity in patterns that constitute plans for actions to achieve the goals. These planning patterns are conceived to provide frames in which the microscopic activity evolves in trajectories that adapted to the immediate environmental conditions detected by new stimuli. This circular sequence forms the action-perception cycle. Its upward limb is understood through correlation of sensory cortical activity with behavior. Now brain-machine interfaces (BMI) offer a means to understand the downward sequence through correlation of behavior with motor cortical activity, beginning with macroscopic goal states and concluding with recording of microscopic MSA trajectories that operate neuroprostheses. Part 1 develops a hypothesis that describes qualitatively the neurodynamics that supports the action-perception cycle and derivative reflex arc. Part 2 describes episodic, “cinematographic” spatial pattern formation and predicts some properties of the macroscopic and mesoscopic frames by which the embedded trajectories of the microscopic activity of cortical sensorimotor neurons might be organized and controlled
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