2,702 research outputs found
A Cost Effective Block Framing Scheme for Underwater Communication
In this paper, the Selective Multiple Acknowledgement (SMA) method, based on Multiple Acknowledgement (MA), is proposed to efficiently reduce the amount of data transmission by redesigning the transmission frame structure and taking into consideration underwater transmission characteristics. The method is suited to integrated underwater system models, as the proposed method can handle the same amount of data in a much more compact frame structure without any appreciable loss of reliability. Herein, the performance of the proposed SMA method was analyzed and compared to those of the conventional Automatic Repeat-reQuest (ARQ), Block Acknowledgement (BA), block response, and MA methods. The efficiency of the underwater sensor network, which forms a large cluster and mostly contains uplink data, is expected to be improved by the proposed method
Feature Re-calibration based Multiple Instance Learning for Whole Slide Image Classification
Whole slide image (WSI) classification is a fundamental task for the
diagnosis and treatment of diseases; but, curation of accurate labels is
time-consuming and limits the application of fully-supervised methods. To
address this, multiple instance learning (MIL) is a popular method that poses
classification as a weakly supervised learning task with slide-level labels
only. While current MIL methods apply variants of the attention mechanism to
re-weight instance features with stronger models, scant attention is paid to
the properties of the data distribution. In this work, we propose to
re-calibrate the distribution of a WSI bag (instances) by using the statistics
of the max-instance (critical) feature. We assume that in binary MIL, positive
bags have larger feature magnitudes than negatives, thus we can enforce the
model to maximize the discrepancy between bags with a metric feature loss that
models positive bags as out-of-distribution. To achieve this, unlike existing
MIL methods that use single-batch training modes, we propose balanced-batch
sampling to effectively use the feature loss i.e., (+/-) bags simultaneously.
Further, we employ a position encoding module (PEM) to model
spatial/morphological information, and perform pooling by multi-head
self-attention (PSMA) with a Transformer encoder. Experimental results on
existing benchmark datasets show our approach is effective and improves over
state-of-the-art MIL methods.Comment: MICCAI 202
Effects of Genetic and Pharmacologic Inhibition of COX-2 on Colitis-associated Carcinogenesis in Mice
COX-2 has been inappropriately overexpressed in various human malignancies, and is considered as one of the representative targets for the chemoprevention of inflammation-associated cancer. In order to assess the role of COX-2 in colitis-induced carcinogenesis, the selective COX-2 inhibitor celecoxib and COX-2 null mice were exploited in an azoxymethane (AOM)-initiated and dextran sulfate sodium (DSS)-promoted murine colon carcinogenesis model. The administration of 2% DSS in drinking water for 1 week after a single intraperitoneal injection of AOM produced colorectal adenomas in 83% of mice, whereas only 27% of mice given AOM alone developed tumors. Oral administration of celecoxib significantly lowered the incidence as well as the multiplicity of colon tumors. The expression of COX-2 and inducible nitric oxide synthase (iNOS) was upregulated in the colon tissues of mice treated with AOM and DSS, and this was inhibited by celecoxib administration. Likewise, celecoxib treatment abrogated the DNA binding of NF-kappa B, a key transcription factor responsible for regulating expression of aforementioned pro-inflammatory enzymes, which was associated with suppression of I kappa B alpha degradation. In the COX-2 null (COX-2(-/-)) mice, there was about 30% reduction in the incidence of colon tumors, and the tumor multiplicity was also markedly reduced (7.7 +/- 2.5 vs. 2.43 +/- 1.4, P < 0.01). As both pharmacologic inhibition and genetic ablation of COX- 2 gene could not completely suppress colon tumor formation following treatment with AOM and DSS, it is speculated that other pro-inflammatory mediators, including COX-1 and iNOS, should be additionally targeted to prevent inflammation-associated colon carcinogenesis.
Geomagnetic field influences probabilistic abstract decision-making in humans
To resolve disputes or determine the order of things, people commonly use
binary choices such as tossing a coin, even though it is obscure whether the
empirical probability equals to the theoretical probability. The geomagnetic
field (GMF) is broadly applied as a sensory cue for various movements in many
organisms including humans, although our understanding is limited. Here we
reveal a GMF-modulated probabilistic abstract decision-making in humans and the
underlying mechanism, exploiting the zero-sum binary stone choice of Go game as
a proof-of-principle. The large-scale data analyses of professional Go matches
and in situ stone choice games showed that the empirical probabilities of the
stone selections were remarkably different from the theoretical probability. In
laboratory experiments, experimental probability in the decision-making was
significantly influenced by GMF conditions and specific magnetic resonance
frequency. Time series and stepwise systematic analyses pinpointed the
intentionally uncontrollable decision-making as a primary modulating target.
Notably, the continuum of GMF lines and anisotropic magnetic interplay between
players were crucial to influence the magnetic field resonance-mediated
abstract decision-making. Our findings provide unique insights into the impact
of sensing GMF in decision-makings at tipping points and the quantum mechanical
mechanism for manifesting the gap between theoretical and empirical probability
in 3-dimensional living space.Comment: 32 pages, 5 figures, 4 supplementary figures, 2 supplementary tables,
and separate 15 ancillary file
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