145 research outputs found
Approximation learning methods of Harmonic Mappings in relation to Hardy Spaces
A new Hardy space Hardy space approach of Dirichlet type problem based on
Tikhonov regularization and Reproducing Hilbert kernel space is discussed in
this paper, which turns out to be a typical extremal problem located on the
upper upper-high complex plane. If considering this in the Hardy space, the
optimization operator of this problem will be highly simplified and an
efficient algorithm is possible. This is mainly realized by the help of
reproducing properties of the functions in the Hardy space of upper-high
complex plane, and the detail algorithm is proposed. Moreover, harmonic
mappings, which is a significant geometric transformation, are commonly used in
many applications such as image processing, since it describes the energy
minimization mappings between individual manifolds. Particularly, when we focus
on the planer mappings between two Euclid planer regions, the harmonic mappings
are exist and unique, which is guaranteed solidly by the existence of harmonic
function. This property is attractive and simulation results are shown in this
paper to ensure the capability of applications such as planer shape distortion
and surface registration.Comment: 2016 3rd International Conference on Informative and Cybernetics for
Computational Social Systems (ICCSS
E2Net: Resource-Efficient Continual Learning with Elastic Expansion Network
Continual Learning methods are designed to learn new tasks without erasing
previous knowledge. However, Continual Learning often requires massive
computational power and storage capacity for satisfactory performance. In this
paper, we propose a resource-efficient continual learning method called the
Elastic Expansion Network (E2Net). Leveraging core subnet distillation and
precise replay sample selection, E2Net achieves superior average accuracy and
diminished forgetting within the same computational and storage constraints,
all while minimizing processing time. In E2Net, we propose Representative
Network Distillation to identify the representative core subnet by assessing
parameter quantity and output similarity with the working network, distilling
analogous subnets within the working network to mitigate reliance on rehearsal
buffers and facilitating knowledge transfer across previous tasks. To enhance
storage resource utilization, we then propose Subnet Constraint Experience
Replay to optimize rehearsal efficiency through a sample storage strategy based
on the structures of representative networks. Extensive experiments conducted
predominantly on cloud environments with diverse datasets and also spanning the
edge environment demonstrate that E2Net consistently outperforms
state-of-the-art methods. In addition, our method outperforms competitors in
terms of both storage and computational requirements
Siamese Labels Auxiliary Network(SiLaNet)
Auxiliary information attracts more and more attention in the area of machine
learning. Attempts so far to include such auxiliary information in
state-of-the-art learning process have often been based on simply appending
these auxiliary features to the data level or feature level. In this paper, we
intend to propose a novel training method with new options and architectures.
Siamese labels, which were used in the training phase as auxiliary modules.
While in the testing phase, the auxiliary module should be removed. Siamese
label module makes it easier to train and improves the performance in testing
process. In general, the main contributions can be summarized as, 1) Siamese
Labels are firstly proposed as auxiliary information to improve the learning
efficiency; 2) We establish a new architecture, Siamese Labels Auxiliary
Network (SilaNet), which is to assist the training of the model; 3) Siamese
Labels Auxiliary Network is applied to compress the model parameters by 50% and
ensure the high accuracy at the same time. For the purpose of comparison, we
tested the network on CIFAR-10 and CIFAR100 using some common models. The
proposed SilaNet performs excellent efficiency both on the accuracy and
robustness
Leveraging Multimodal Features and Item-level User Feedback for Bundle Construction
Automatic bundle construction is a crucial prerequisite step in various
bundle-aware online services. Previous approaches are mostly designed to model
the bundling strategy of existing bundles. However, it is hard to acquire
large-scale well-curated bundle dataset, especially for those platforms that
have not offered bundle services before. Even for platforms with mature bundle
services, there are still many items that are included in few or even zero
bundles, which give rise to sparsity and cold-start challenges in the bundle
construction models. To tackle these issues, we target at leveraging multimodal
features, item-level user feedback signals, and the bundle composition
information, to achieve a comprehensive formulation of bundle construction.
Nevertheless, such formulation poses two new technical challenges: 1) how to
learn effective representations by optimally unifying multiple features, and 2)
how to address the problems of modality missing, noise, and sparsity problems
induced by the incomplete query bundles. In this work, to address these
technical challenges, we propose a Contrastive Learning-enhanced Hierarchical
Encoder method (CLHE). Specifically, we use self-attention modules to combine
the multimodal and multi-item features, and then leverage both item- and
bundle-level contrastive learning to enhance the representation learning, thus
to counter the modality missing, noise, and sparsity problems. Extensive
experiments on four datasets in two application domains demonstrate that our
method outperforms a list of SOTA methods. The code and dataset are available
at https://github.com/Xiaohao-Liu/CLHE
Lung Nodule Segmentation and Uncertain Region Prediction with an Uncertainty-Aware Attention Mechanism
Radiologists possess diverse training and clinical experiences, leading to
variations in the segmentation annotations of lung nodules and resulting in
segmentation uncertainty.Conventional methods typically select a single
annotation as the learning target or attempt to learn a latent space comprising
multiple annotations. However, these approaches fail to leverage the valuable
information inherent in the consensus and disagreements among the multiple
annotations. In this paper, we propose an Uncertainty-Aware Attention Mechanism
(UAAM) that utilizes consensus and disagreements among multiple annotations to
facilitate better segmentation. To this end, we introduce the Multi-Confidence
Mask (MCM), which combines a Low-Confidence (LC) Mask and a High-Confidence
(HC) Mask.The LC mask indicates regions with low segmentation confidence, where
radiologists may have different segmentation choices. Following UAAM, we
further design an Uncertainty-Guide Multi-Confidence Segmentation Network
(UGMCS-Net), which contains three modules: a Feature Extracting Module that
captures a general feature of a lung nodule, an Uncertainty-Aware Module that
produces three features for the the annotations' union, intersection, and
annotation set, and an Intersection-Union Constraining Module that uses
distances between the three features to balance the predictions of final
segmentation and MCM. To comprehensively demonstrate the performance of our
method, we propose a Complex Nodule Validation on LIDC-IDRI, which tests
UGMCS-Net's segmentation performance on lung nodules that are difficult to
segment using common methods. Experimental results demonstrate that our method
can significantly improve the segmentation performance on nodules that are
difficult to segment using conventional methods.Comment: 10 pages, 10 figures. We have reported a preliminary version of this
work in MICCAI 202
Plasmonic hot electrons for sensing, photodetection, and solar energy applications: A perspective
In plasmonic metals, surface plasmon resonance decays and generates hot electrons and hot holes through non-radiative Landau damping. These hot carriers are highly energetic, which can be modulated by the plasmonic material, size, shape, and surrounding dielectric medium. A plasmonic metal nanostructure, which can absorb incident light in an extended spectral range and transfer the absorbed light energy to adjacent molecules or semiconductors, functions as a āplasmonic photosensitizer.ā This article deals with the generation, emission, transfer, and energetics of plasmonic hot carriers. It also describes the mechanisms of hot electron transfer from the plasmonic metal to the surface adsorbates or to the adjacent semiconductors. In addition, this article highlights the applications of plasmonic hot electrons in photodetectors, photocatalysts, photoelectrochemical cells, photovoltaics, biosensors, and chemical sensors. It discusses the applications and the design principles of plasmonic materials and devices
Family functioning as a moderator in the relation between perceived stress and psychotic-like experiences among adolescents during COVID-19
Background: The COVID-19 pandemic has increased psychological stress among adolescents, and the relation between perceived stress (PS) and psychotic-like experiences (PLEs) has been well-established. However, little is known about the role of family functioning (FF) in this relation, especially when adolescents experienced the extended lockdown period with family members. Methods: A total of 4807 adolescents completed this retrospective paper-and-pencil survey after school reopening between May 14th and June 6th, 2020 in Hunan Province, China. We measured PS with the Perceived stress scale (PSS-10), PLEs with the eight positive items from Community Assessment of Psychic Experiences (CAPE-8), and FF with the Family APGAR scale. We conducted subgroup analysis based on three FF levels (good, moderate, and poor) determined by previous studies. Finally, correlation and moderation analysis were performed to detect the effect of FF in the relation between PS and PLEs after adjusting for demographic variables. Results: Adolescents with poor FF had higher levels of PS and higher prevalence of PLEs compared to those with good FF (both p \u3c 0.001). FF was negatively associated with both PS (r = ā0.34, p \u3c 0.001) and PLEs (r = ā0.29, p \u3c 0.001). Higher FF significantly attenuated the effect of PS on PLEs after adjusting for sex and age (effect = ā0.011, bootstrap 95% CI -0.018, ā0.005). Conclusion: Our findings indicate that well-functioned family could protect against stress-induced PLEs among adolescents during this crisis. Thus family system could be an early interventional target for distressing psychotic-like experiences in youngsters
Enhanced secretion of hepatocyte growth factor in human umbilical cord mesenchymal stem cells ameliorates pulmonary fibrosis induced by bleomycin in rats
Umbilical cord mesenchymal stem cells (UCMSCs) are a reportedly promising choice in the treatment of irreversible pulmonary fibrosis and lethal interstitial lung disease with limited drug treatment options. In this study, we investigated the therapeutic efficacy of UCMSCs overexpressing hepatocyte growth factor (HGF), which is considered one of the main anti-fibrotic factors secreted by MSCs. Adenovirus vector carrying the HGF gene was transfected into UCMSCs to produce HGF-modified UCMSCs (HGF-UCMSCs). Transfection promoted the proliferation of UCMSCs and did not change the morphology, and differentiation ability, or biomarkers. Rats were injected with HGF-UCMSCs on days 7 and 11 after intratracheal administration of bleomycin (10Ā mg/kg). We performed an analysis of histopathology and lung function to evaluate the anti-fibrotic effect. The results showed that HGF-UCMSCs decreased the Ashcroft scores in hematoxylin and eosin-stained sections, the percentage positive area in Masson trichrome-stained sections, and the hydroxyproline level in lungs. Forced expiratory volume in the first 300Ā m/forced vital capacity was also improved by HGF-UCMSCs. To explore the possible therapeutic mechanism of HGF-UCMSCs, we detected inflammatory factors in the lungs and performed mRNA sequencing in UCMSCs and HGF-UCMSCs. The data indicated that inhibition of interleukin-17 in the lung may be related to the anti-fibrosis of HGF-UCMSCs, and overexpressed HGF probably played a primary role in the treatment. Collectively, our study findings suggested that the overexpression of HGF may improve the anti-fibrotic effect of UCMSCs through directly or indirectly interacting with interleukin-17-producing cells in fibrotic lungs
Expression of MK-1 and Regā £ and its clinicopathological significances in the benign and malignant lesions of gallbladder
<p>Abstract</p> <p>Background</p> <p>To study the expression of MK-1 and Regā
£ and to detect their pathological significances in benign and malignant lesions of gallbladder.</p> <p>Methods</p> <p>The expression of MK-1 and Regā
£ was detected by immunohistochemical method in paraffin-embedded sections of surgical resected specimens from gallbladder adenocarcinoma (n = 108), peritumoral tissues (n = 46), adenomatous polyp (n = 15), and chronic cholecystitis (n = 35).</p> <p>Results</p> <p>The positive rate of MK-1 or Regā
£ expression was significantly higher in gallbladder adenocarcinoma than that in peritumoral tissues (Ļ<sup>2</sup><sub>MK-1 </sub>= 18.76, <it>P </it>< 0.01; Ļ<sup>2</sup><sub>Regā
£ </sub>= 9.92, <it>P </it>< 0.01), denomatous polyp (Ļ<sup>2</sup><sub>MK-1 </sub>= 9.49, <it>P </it>< 0.01; Ļ<sup>2</sup><sub>Regā
£ </sub>= 8.59, <it>P </it>< 0.01) and chronic cholecystitis (Ļ<sup>2</sup><sub>MK-1 </sub>= 24.11, <it>P </it>< 0.01; Ļ<sup>2</sup><sub>Regā
£ </sub>= 19.24, <it>P </it>< 0.01). The positive cases of MK-1 and/or Regā
£ in the benign lesions showed moderately- or severe-atypical hyperplasia of gallbladder epitheli. The positive rates of MK-1 were significantly higher in the cases of well-differentiated adenocarcinoma, no-metastasis of lymph node, and no-invasiveness of regional tissues than those in the ones of differentiated adenocarcinoma, metastasis of lymph node, and invasiveness of regional tissues in gallbladder adenocarcinoma (<it>P </it>< 0.05 or <it>P </it>< 0.01). On the contrary, the positive rates of Regā
£ were significantly lower in the cases of well-differentiated adenocarcinoma, no-metastasis of lymph node, and no-invasiveness of regional tissues than those in the ones of differentiated adenocarcinoma, metastasis of lymph node, and invasiveness of regional tissues in gallbladder adenocarcinoma (<it>P </it>< 0.05 or <it>P </it>< 0.01). Univariate Kaplan-Meier analysis showed that decreased expression of MK-1 (<it>P </it>= 0.09) or increased expression of Regā
£ (<it>P </it>= 0.003) was associated with decreased overall survival. Multivariate Cox regression analysis showed that decreased expression of MK-1 (<it>P </it>= 0.033) and increased expression of Regā
£ (<it>P </it>= 0.008) was an independent prognostic predictor in gallbladder adenocarcinoma.</p> <p>Conclusions</p> <p>The expression of MK-1 and/or Regā
£ might be closely related to the carcinogenesis, clinical biological behaviors, and prognosis of gallbladder adenocarcinoma.</p
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