1,662 research outputs found
INSIDE: Steering Spatial Attention with Non-Imaging Information in CNNs
We consider the problem of integrating non-imaging information into
segmentation networks to improve performance. Conditioning layers such as FiLM
provide the means to selectively amplify or suppress the contribution of
different feature maps in a linear fashion. However, spatial dependency is
difficult to learn within a convolutional paradigm. In this paper, we propose a
mechanism to allow for spatial localisation conditioned on non-imaging
information, using a feature-wise attention mechanism comprising a
differentiable parametrised function (e.g. Gaussian), prior to applying the
feature-wise modulation. We name our method INstance modulation with SpatIal
DEpendency (INSIDE). The conditioning information might comprise any factors
that relate to spatial or spatio-temporal information such as lesion location,
size, and cardiac cycle phase. Our method can be trained end-to-end and does
not require additional supervision. We evaluate the method on two datasets: a
new CLEVR-Seg dataset where we segment objects based on location, and the ACDC
dataset conditioned on cardiac phase and slice location within the volume. Code
and the CLEVR-Seg dataset are available at https://github.com/jacenkow/inside.Comment: Accepted at International Conference on Medical Image Computing and
Computer Assisted Intervention (MICCAI) 202
Comprehensive Analysis of Market Conditions in the Foreign Exchange Market: Fluctuation Scaling and Variance-Covariance Matrix
We investigate quotation and transaction activities in the foreign exchange
market for every week during the period of June 2007 to December 2010. A
scaling relationship between the mean values of number of quotations (or number
of transactions) for various currency pairs and the corresponding standard
deviations holds for a majority of the weeks. However, the scaling breaks in
some time intervals, which is related to the emergence of market shocks. There
is a monotonous relationship between values of scaling indices and global
averages of currency pair cross-correlations when both quantities are observed
for various window lengths .Comment: 13 pages, 10 figure
Control of intestinal stem cell function and proliferation by mitochondrial pyruvate metabolism.
Most differentiated cells convert glucose to pyruvate in the cytosol through glycolysis, followed by pyruvate oxidation in the mitochondria. These processes are linked by the mitochondrial pyruvate carrier (MPC), which is required for efficient mitochondrial pyruvate uptake. In contrast, proliferative cells, including many cancer and stem cells, perform glycolysis robustly but limit fractional mitochondrial pyruvate oxidation. We sought to understand the role this transition from glycolysis to pyruvate oxidation plays in stem cell maintenance and differentiation. Loss of the MPC in Lgr5-EGFP-positive stem cells, or treatment of intestinal organoids with an MPC inhibitor, increases proliferation and expands the stem cell compartment. Similarly, genetic deletion of the MPC in Drosophila intestinal stem cells also increases proliferation, whereas MPC overexpression suppresses stem cell proliferation. These data demonstrate that limiting mitochondrial pyruvate metabolism is necessary and sufficient to maintain the proliferation of intestinal stem cells
Recognizing Speech in a Novel Accent: The Motor Theory of Speech Perception Reframed
The motor theory of speech perception holds that we perceive the speech of
another in terms of a motor representation of that speech. However, when we
have learned to recognize a foreign accent, it seems plausible that recognition
of a word rarely involves reconstruction of the speech gestures of the speaker
rather than the listener. To better assess the motor theory and this
observation, we proceed in three stages. Part 1 places the motor theory of
speech perception in a larger framework based on our earlier models of the
adaptive formation of mirror neurons for grasping, and for viewing extensions
of that mirror system as part of a larger system for neuro-linguistic
processing, augmented by the present consideration of recognizing speech in a
novel accent. Part 2 then offers a novel computational model of how a listener
comes to understand the speech of someone speaking the listener's native
language with a foreign accent. The core tenet of the model is that the
listener uses hypotheses about the word the speaker is currently uttering to
update probabilities linking the sound produced by the speaker to phonemes in
the native language repertoire of the listener. This, on average, improves the
recognition of later words. This model is neutral regarding the nature of the
representations it uses (motor vs. auditory). It serve as a reference point for
the discussion in Part 3, which proposes a dual-stream neuro-linguistic
architecture to revisits claims for and against the motor theory of speech
perception and the relevance of mirror neurons, and extracts some implications
for the reframing of the motor theory
Tricholithobezoar Causing Gastric Perforation
A bezoar is an intraluminal mass formed by the accumulation of undigested material in the gastrointestinal tract. Trichobezoar is a rare condition seen almost exclusively in young women with trichotillomania and trichotillophagia. When not recognized, the trichobezoar continues to grow, which increases the risk of severe complications such as gastric ulceration and even perforation. Formation of a gallstone within the trichobezoar (tricholithobezoar) is an event that has not yet been described. We report the case of a 22-year-old woman admitted to the emergency room with signals and symptoms of an epigastric mass and perforative acute abdomen. Radiological study revealed bilateral pneumoperitoneum. Personal history revealed depressive syndrome, trichotillomania and trichophagia. With a diagnosis of visceral perforation, an urgent exploratory laparotomy was performed. This confirmed the diagnosis of gastric perforation due to a large trichobezoar with the formation of a gastrolith that was removed by anterior gastrotomy. Biochemical study of the gastric stone revealed that it was composed of bile salts. There were no complications. The patient was discharged on the 5th postoperative day and was referred for psychiatric treatment
Quantitative Analysis of Serum Procollagen Type I C-Terminal Propeptide by Immunoassay on Microchip
BACKGROUND: Sandwich enzyme-linked immunosorbent assay (ELISA) is one of the most frequently employed assays for clinical diagnosis, since this enables the investigator to identify specific protein biomarkers. However, the conventional assay using a 96-well microtitration plate is time- and sample-consuming, and therefore is not suitable for rapid diagnosis. To overcome these drawbacks, we performed a sandwich ELISA on a microchip. METHODS AND FINDINGS: The microchip was made of cyclic olefin copolymer with straight microchannels that were 300 µm wide and 100 µm deep. For the construction of a sandwich ELISA for procollagen type I C-peptide (PICP), a biomarker for bone formation, we used a piezoelectric inkjet printing system for the deposition and fixation of the 1st anti-PICP antibody on the surface of the microchannel. After the infusion of the mixture of 2.0 µl of peroxidase-labeled 2nd anti-PICP antibody and 0.4 µl of sample to the microchannel and a 30-min incubation, the substrate for peroxidase was infused into the microchannel; and the luminescence intensity of each spot of 1st antibody was measured by CCD camera. A linear relationship was observed between PICP concentration and luminescence intensity over the range of 0 to 600 ng/ml (r(2) = 0.991), and the detection limit was 4.7 ng/ml. Blood PICP concentrations of 6 subjects estimated from microchip were compared with results obtained by the conventional method. Good correlation was observed between methods according to simple linear regression analysis (R(2) = 0.9914). The within-day and between-days reproducibilities were 3.2-7.4 and 4.4-6.8%, respectively. This assay reduced the time for the antigen-antibody reaction to 1/6, and the consumption of samples and reagents to 1/50 compared with the conventional method. CONCLUSION: This assay enabled us to determine serum PICP with accuracy, high sensitivity, time saving ability, and low consumption of sample and reagents, and thus will be applicable to clinic diagnosis
Prognostic value of radical cystoprostatectomy in men with bladder cancer infiltrating prostate versus co-existing prostate cancer: a research study
<p>Abstract</p> <p>Background</p> <p>The aim of the following study is to evaluate the advancement of incidentally diagnosed prostate cancer in specimen after cystoprostatectomies caused by muscle-invasive bladder cancer. Secondly we assessed the survival in patients after radical cystoprostatectomy whose postoperative specimen was characterized by the presence of co-existing prostate cancer or prostate infiltration by urothelial bladder cancer.</p> <p>Methods</p> <p>Between 1993 and 2009 a total of 320 patients with muscle-invasive bladder cancer underwent cystoprostatectomy. The first analyzed group consisted of 52 patients with bladder cancer infiltrating prostate, while the second group consisted of 21 patients with co-existing prostate cancer. In all patients cancer specific survival and progression were analyzed. Average follow up was 75.2 months (range: 0 - 181).</p> <p>Results</p> <p>Cancer-specific survival was significantly shorter in group I (p = 0.03). Neoplastic progression in patients from group I was observed in 42.2% of patients, while in patients from group II in 23.6% of patients (p = 0.04). No statistical difference was observed in the percentage of positive lymph nodes between the groups (p = 0.22). The median Gleason score in patients with co-existing prostate cancer was equal to 5. The stage of prostate cancer pT<sub>2</sub>/pT<sub>3 </sub>was equal to 20 (96%)/1 (4%) patients. 12 (57%) prostate cancers were clinically insignificant. Biochemical recurrence occurred in 2 (9%) patients.</p> <p>Conclusions</p> <p indent="1">1. Incidentally diagnosed prostate cancer in specimen after cystoprostatectomies is frequently clinically insignificant and characterized by low progression.</p> <p indent="1">2. Patients with bladder cancer infiltrating prostate are characterized by higher percentage of progression and death in comparison with patients with co-existing prostate cancer.</p
Cytogenetic divergence between two sympatric species of Characidium (Teleostei, Characiformes, Crenuchidae) from the Machado River, Minas Gerais, Brazil
Evidence of means–end behavior in Asian elephants (Elephas maximus)
The present study explores to what extent Asian elephants show “means–end” behavior. We used captive Asian elephants (N = 2) to conduct four variations of the Piagetian “support” problem, which involves a goal object that is out of reach, but rests on a support within reach. In the first condition, elephants were simultaneously presented with two identical trays serving as the “support”, with the bait on one tray and the other tray left empty. In the next two conditions, the bait was placed on one tray, while additional bait was placed beside the other tray. In the last condition, both trays contained bait, but one of the trays had a small gap which prevented the elephants from reaching the reward. Subjects were required to choose and pull either tray with their trunk and to obtain the bait (i.e. goal). Results showed that one elephant performed all of the support problems significantly above chance after several sessions, suggesting that the elephant was capable of understanding that pulling the tray was the “means” for achieving the “end” of obtaining the bait. This study showed that elephants show means–end behavior when subjected to a Piagetian “support” task, and indicates that such goal-directed behavior occurs in species other than primates
Asymmetric Wolbachia Segregation during Early Brugia malayi Embryogenesis Determines Its Distribution in Adult Host Tissues
Wolbachia are required for filarial nematode survival and
fertility and contribute to the immune responses associated with human filarial
diseases. Here we developed whole-mount immunofluorescence techniques to
characterize Wolbachia somatic and germline transmission
patterns and tissue distribution in Brugia malayi, a nematode
responsible for lymphatic filariasis. In the initial embryonic divisions,
Wolbachia segregate asymmetrically such that they occupy
only a small subset of cells in the developing embryo, facilitating their
concentration in the adult hypodermal chords and female germline.
Wolbachia are not found in male reproductive tissues and
the absence of Wolbachia from embryonic germline precursors in
half of the embryos indicates Wolbachia loss from the male
germline may occur in early embryogenesis. Wolbachia rely on
fusion of hypodermal cells to populate adult chords. Finally, we detect
Wolbachia in the secretory canal lumen suggesting living
worms may release bacteria and/or their products into their host
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