1,181 research outputs found

    Does imaging genetics reveal shared mechanisms behind psychotic symptom profile?

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    Current diagnoses of schizophrenia (SZ) and bipolar disorder (BD) are classified by phenomenological principles and clinical descriptions. The boundaries of the disorders are merging with accumulating shared genetic and brain mechanisms being uncovered. Imaging genetics is a useful tool to understand the impact of genetic variations on the brain. It also enables capturing the behavioral implication of those genes and associated brain alterations. This study aimed to reveal the associations among sets of genetic variations, structural brain abnormalities, and clinical symptom profiles shared in schizophrenia and bipolar disorders by imaging genetics and multivariate approaches. First, we mapped the symptom profiles onto brain patterns. Distinct structural brain patterns guided with symptom profiles represented by positive and negative syndrome scale (PANSS), through parallel independent component analysis (pICA) were extracted. Brain patterns related to positive symptoms, mood, and apathy were discovered in SZ and BD. Second, we investigated the relationships of symptoms and brain patterns regardless of diagnostic categories by projecting each disorder’s structural brain and PANSS patterns into the other disorder group (e.g., projecting patterns from schizophrenia to bipolar and vice versa) to reassess the associations. The projected brain patterns showed associations with broad symptoms rather than the original PANSS patterns. Finally, we explored the potential shared genetic mechanisms behind symptom-brain patterns by investigating the effect of polygenic risk scores (PRS) from the Psychiatric Genomics Consortium (PGC). Both SZ and BD PRS were significantly associated with the positive symptom-related brain patterns in SZ. Higher genetic risks contributed to more severe gray matter concentration (GMC) reductions in the temporal regions of SZ patients, and it may lead to worse positive symptoms. Correspondingly, in the BD, both SZ and BD PRS were significantly associated with the mood symptom-related brain patterns. Higher risks contributed to more severe gray matter concentration (GMC) reductions in the frontal-temporal-parietal circuits with worse mood symptoms. The polygenic effects behind the apathy component may be subtle. The results helped improve the understanding of categories of psychotic disorders starting from schizophrenia and bipolar disorder. It may essentially contribute to the more precise diagnosis and treatment for heterogeneous populations with psychosis

    Learning to Guide Decoding for Image Captioning

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    Recently, much advance has been made in image captioning, and an encoder-decoder framework has achieved outstanding performance for this task. In this paper, we propose an extension of the encoder-decoder framework by adding a component called guiding network. The guiding network models the attribute properties of input images, and its output is leveraged to compose the input of the decoder at each time step. The guiding network can be plugged into the current encoder-decoder framework and trained in an end-to-end manner. Hence, the guiding vector can be adaptively learned according to the signal from the decoder, making itself to embed information from both image and language. Additionally, discriminative supervision can be employed to further improve the quality of guidance. The advantages of our proposed approach are verified by experiments carried out on the MS COCO dataset.Comment: AAAI-1

    Fast Incremental SVDD Learning Algorithm with the Gaussian Kernel

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    Support vector data description (SVDD) is a machine learning technique that is used for single-class classification and outlier detection. The idea of SVDD is to find a set of support vectors that defines a boundary around data. When dealing with online or large data, existing batch SVDD methods have to be rerun in each iteration. We propose an incremental learning algorithm for SVDD that uses the Gaussian kernel. This algorithm builds on the observation that all support vectors on the boundary have the same distance to the center of sphere in a higher-dimensional feature space as mapped by the Gaussian kernel function. Each iteration involves only the existing support vectors and the new data point. Moreover, the algorithm is based solely on matrix manipulations; the support vectors and their corresponding Lagrange multiplier αi\alpha_i's are automatically selected and determined in each iteration. It can be seen that the complexity of our algorithm in each iteration is only O(k2)O(k^2), where kk is the number of support vectors. Experimental results on some real data sets indicate that FISVDD demonstrates significant gains in efficiency with almost no loss in either outlier detection accuracy or objective function value.Comment: 18 pages, 1 table, 4 figure

    Hierarchical Photo-Scene Encoder for Album Storytelling

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    In this paper, we propose a novel model with a hierarchical photo-scene encoder and a reconstructor for the task of album storytelling. The photo-scene encoder contains two sub-encoders, namely the photo and scene encoders, which are stacked together and behave hierarchically to fully exploit the structure information of the photos within an album. Specifically, the photo encoder generates semantic representation for each photo while exploiting temporal relationships among them. The scene encoder, relying on the obtained photo representations, is responsible for detecting the scene changes and generating scene representations. Subsequently, the decoder dynamically and attentively summarizes the encoded photo and scene representations to generate a sequence of album representations, based on which a story consisting of multiple coherent sentences is generated. In order to fully extract the useful semantic information from an album, a reconstructor is employed to reproduce the summarized album representations based on the hidden states of the decoder. The proposed model can be trained in an end-to-end manner, which results in an improved performance over the state-of-the-arts on the public visual storytelling (VIST) dataset. Ablation studies further demonstrate the effectiveness of the proposed hierarchical photo-scene encoder and reconstructor.Comment: 8 pages, 4 figure

    LGFCTR: Local and Global Feature Convolutional Transformer for Image Matching

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    Image matching that finding robust and accurate correspondences across images is a challenging task under extreme conditions. Capturing local and global features simultaneously is an important way to mitigate such an issue but recent transformer-based decoders were still stuck in the issues that CNN-based encoders only extract local features and the transformers lack locality. Inspired by the locality and implicit positional encoding of convolutions, a novel convolutional transformer is proposed to capture both local contexts and global structures more sufficiently for detector-free matching. Firstly, a universal FPN-like framework captures global structures in self-encoder as well as cross-decoder by transformers and compensates local contexts as well as implicit positional encoding by convolutions. Secondly, a novel convolutional transformer module explores multi-scale long range dependencies by a novel multi-scale attention and further aggregates local information inside dependencies for enhancing locality. Finally, a novel regression-based sub-pixel refinement module exploits the whole fine-grained window features for fine-level positional deviation regression. The proposed method achieves superior performances on a wide range of benchmarks. The code will be available on https://github.com/zwh0527/LGFCTR.Comment: 8 pages of main text, 7 pages of supplementary material, 3 pages of references, 6 figures in main text and 8 figures in supplementary material, 5 tables in main text and 2 tables in supplementary materia

    Theoretic Analysis and Extremely Easy Algorithms for Domain Adaptive Feature Learning

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    Domain adaptation problems arise in a variety of applications, where a training dataset from the \textit{source} domain and a test dataset from the \textit{target} domain typically follow different distributions. The primary difficulty in designing effective learning models to solve such problems lies in how to bridge the gap between the source and target distributions. In this paper, we provide comprehensive analysis of feature learning algorithms used in conjunction with linear classifiers for domain adaptation. Our analysis shows that in order to achieve good adaptation performance, the second moments of the source domain distribution and target domain distribution should be similar. Based on our new analysis, a novel extremely easy feature learning algorithm for domain adaptation is proposed. Furthermore, our algorithm is extended by leveraging multiple layers, leading to a deep linear model. We evaluate the effectiveness of the proposed algorithms in terms of domain adaptation tasks on the Amazon review dataset and the spam dataset from the ECML/PKDD 2006 discovery challenge.Comment: ijca

    The Path and Enlightenment of Data-Driven Digital Transformation of Organizational Learning ——A Case Study of the Practice of China Telecom

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    This paper took China Telecom as a case. It has analyzed data-driven digital transformation in organizational learning, and summarized the methods and enlightenments of digital transformation

    Prefix-Tuning Based Unsupervised Text Style Transfer

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    Unsupervised text style transfer aims at training a generative model that can alter the style of the input sentence while preserving its content without using any parallel data. In this paper, we employ powerful pre-trained large language models and present a new prefix-tuning-based method for unsupervised text style transfer. We construct three different kinds of prefixes, i.e., \textit{shared prefix, style prefix}, and \textit{content prefix}, to encode task-specific information, target style, and the content information of the input sentence, respectively. Compared to embeddings used by previous works, the proposed prefixes can provide richer information for the model. Furthermore, we adopt a recursive way of using language models in the process of style transfer. This strategy provides a more effective way for the interactions between the input sentence and GPT-2, helps the model construct more informative prefixes, and thus, helps improve the performance. Evaluations on the well-known datasets show that our method outperforms the state-of-the-art baselines. Results, analysis of ablation studies, and subjective evaluations from humans are also provided for a deeper understanding of the proposed method
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