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Simple Summary: Due to most traditional high-throughput experiments are tedious and laborious in identifying potential protein–protein interaction. To better improve accuracy prediction in protein–protein interactions. We proposed a novel computational method that can identify unknown protein–protein interaction efficiently and hope this method can provide a helpful idea and tool for proteomics research. Protein–protein interactions (PPIs) play an essential role in many biological cellular functions. However, it is still tedious and time-consuming to identify protein–protein interactions through traditional experimental methods. For this reason, it is imperative and necessary to develop a computational method for predicting PPIs efficiently. This paper explores a novel computational method for detecting PPIs from protein sequence, the approach which mainly adopts the feature extraction method: Locality Preserving Projections (LPP) and classifier: Rotation Forest (RF). Specifically, we first employ the Position Specific Scoring Matrix (PSSM), which can remain evolutionary information of biological for representing protein sequence efficiently. Then, the LPP descriptor is applied to extract feature vectors from PSSM. The feature vectors are fed into the RF to obtain the final results. The proposed method is applied to two datasets: Yeast and H. pylori, and obtained an average accuracy of 92.81% and 92.56%, respectively. We also compare it with K nearest neighbors (KNN) and support vector machine (SVM) to better evaluate the performance of the proposed method. In summary, all experimental results indicate that the proposed approach is stable and robust for predicting PPIs and promising to be a useful tool for proteomics research. [ABSTRACT FROM AUTHOR]

Unsupervised 3D model analysis has attracted tremendous attentions with the increasing growth of 3D model data and the extensive human annotations. Many effective methods have been designed to address the 3D model analysis with labeled information, while rare methods devote to unsupervised deep learning due to the difficulty of mining reliable information. In this paper, we propose a novel unsupervised deep learning method named joint local correlation and global contextual information (LCGC) for 3D model retrieval and classification, which mines the reliable triplet set and uses triplet loss to optimize the deep neural network. Our method proposes two schemes: 1) Local self-correlation information learning, which adopts the intra and inter information to construct the view-level triplet set. 2) Global neighbor contextual information learning, which employs the neighbor contextual information to explore the reliable relations among 3D models and construct the model-level triplet set. The above schemes encourage that the selected triple set can been used to improve the discrimination of learned features. Extensive evaluations on two large-scale datasets, ModelNet40 and ShapeNet55, have demonstrated the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

Cross-view geo-localization is to spot images of the same geographic target from different platforms, e.g., drone-view cameras and satellites. It is challenging in the large visual appearance changes caused by extreme viewpoint variations. Existing methods usually concentrate on mining the fine-grained feature of the geographic target in the image center, but underestimate the contextual information in neighbor areas. In this work, we argue that neighbor areas can be leveraged as auxiliary information, enriching discriminative clues for geo-localization. Specifically, we introduce a simple and effective deep neural network, called Local Pattern Network (LPN), to take advantage of contextual information in an end-to-end manner. Without using extra part estimators, LPN adopts a square-ring feature partition strategy, which provides the attention according to the distance to the image center. It eases the part matching and enables the part-wise representation learning. Owing to the square-ring partition design, the proposed LPN has good scalability to rotation variations and achieves competitive results on three prevailing benchmarks, i.e., University-1652, CVUSA and CVACT. Besides, we also show the proposed LPN can be easily embedded into other frameworks to further boost performance. [ABSTRACT FROM AUTHOR]

The optical remote sensing images (RSIs) show various spatial resolutions and cluttered background, where salient objects with different scales, types, and orientations are presented in diverse RSI scenes. Therefore, it is inappropriate to directly extend cutting-edge saliency detection methods for conventional RGB images to optical RSIs. Besides, the existing saliency models targeting RSIs often render imperfect saliency maps, where some of them are with coarse boundary details. To solve this problem, this article attempts to introduce the edge information to precisely detect salient objects in RSIs. Accordingly, we propose an edge-aware multiscale feature integration network (EMFI-Net) for salient object detection by conducting multiscale feature integration under the explicit and implicit assistance of salient edge cues. Specifically, our network contains two parts including the encoder and decoder. First, the encoder extracts multiscale deep features from three RSIs with different resolutions, where the high-level deep semantic features from three RSIs are integrated using a cascaded feature fusion module. Second, the encoder explicitly enriches the multiscale deep features by integrating the salient edge cues extracted by a salient edge extraction module. Meanwhile, we also implicitly deploy an edge-aware constraint to the supervision of the saliency map prediction by introducing a hybrid loss function. Finally, the decoder integrates the enriched multiscale deep features in a coarse-to-fine way, yielding a high-quality saliency map. The experiments conducted on two public optical RSI datasets clearly prove the effectiveness and superiority of the proposed EMFI-Net against the state-of-the-art saliency models. [ABSTRACT FROM AUTHOR]

Effective 3D shape retrieval and recognition are challenging but important tasks in computer vision research field, which have attracted much attention in recent decades. Although recent progress has shown significant improvement of deep learning methods on 3D shape retrieval and recognition performance, it is still under investigated of how to jointly learn an optimal representation of 3D shapes considering their relationships. To tackle this issue, we propose a multi-scale representation learning method on hypergraph for 3D shape retrieval and recognition, called multi-scale hypergraph neural network (MHGNN). In this method, the correlation among 3D shapes is formulated in a hypergraph and a hypergraph convolution process is conducted to learn the representations. Here, multiple representations can be obtained through different convolution layers, leading to multi-scale representations of 3D shapes. A fusion module is then introduced to combine these representations for 3D shape retrieval and recognition. The main advantages of our method lie in 1) the high-order correlation among 3D shapes can be investigated in the framework and 2) the joint multi-scale representation can be more robust for comparison. Comparisons with state-of-the-art methods on the public ModelNet40 dataset demonstrate remarkable performance improvement of our proposed method on the 3D shape retrieval task. Meanwhile, experiments on recognition tasks also show better results of our proposed method, which indicate the superiority of our method on learning better representation for retrieval and recognition. [ABSTRACT FROM AUTHOR]

Hashing is an efficient method for nearest neighbor search in large-scale data space by embedding high-dimensional feature descriptors into a similarity preserving Hamming space with a low dimension. However, large-scale high-speed retrieval through binary code has a certain degree of reduction in retrieval accuracy compared to traditional retrieval methods. We have noticed that multi-view methods can well preserve the diverse characteristics of data. Therefore, we try to introduce the multi-view deep neural network into the hash learning field, and design an efficient and innovative retrieval model, which has achieved a significant improvement in retrieval performance. In this paper, we propose a supervised multi-view hash model which can enhance the multi-view information through neural networks. This is a completely new hash learning method that combines multi-view and deep learning methods. The proposed method utilizes an effective view stability evaluation method to actively explore the relationship among views, which will affect the optimization direction of the entire network. We have also designed a variety of multi-data fusion methods in the Hamming space to preserve the advantages of both convolution and multi-view. In order to avoid excessive computing resources on the enhancement procedure during retrieval, we set up a separate structure called memory network which participates in training together. The proposed method is systematically evaluated on the CIFAR-10, NUS-WIDE and MS-COCO datasets, and the results show that our method significantly outperforms the state-of-the-art single-view and multi-view hashing methods. [ABSTRACT FROM AUTHOR]

Image captioning, a challenging task where the machine automatically describes an image with natural language, has drawn significant attention in recent years. Despite the remarkable improvements of recent approaches, however, these methods are built upon a large set of training image-sentence pairs. The expensive labor efforts hence limit the captioning model to describe the wider world. In this paper, we present a novel network structure, Cascaded Revision Network, which aims at relieving the problem by equipping the model with out-of-domain knowledge. CRN first tries its best to describe an image using the existing vocabulary from in-domain knowledge. Due to the lack of out-of-domain knowledge, the caption may be inaccurate or include ambiguous words for the image with unknown (novel) objects. We propose to re-edit the primary captioning sentence by a series of cascaded operations. We introduce a perplexity predictor to find out which words are most likely to be inaccurate given the input image. Thereafter, we utilize external knowledge from a pretrained object detection model and select more accurate words from detection results by the visual matching module. In the last step, we design a semantic matching module to ensure that the novel object is fit in the right position. By this novel cascaded captioning-revising mechanism, CRN can accurately describe images with unseen objects. We validate the proposed method with state-of-the-art performance on the held-out MSCOCO dataset as well as scale to ImageNet, demonstrating the effectiveness of our method. [ABSTRACT FROM AUTHOR]

Three-dimensional multi-modal data are used to represent 3D objects in the real world in different ways. Features separately extracted from multimodality data are often poorly correlated. Recent solutions leveraging the attention mechanism to learn a joint-network for the fusion of multimodality features have weak generalization capability. In this paper, we propose a hamming embedding sensitivity network to address the problem of effectively fusing multimodality features. The proposed network called HamNet is the first end-to-end framework with the capacity to theoretically integrate data from all modalities with a unified architecture for 3D shape representation, which can be used for 3D shape retrieval and recognition. HamNet uses the feature concealment module to achieve effective deep feature fusion. The basic idea of the concealment module is to re-weight the features from each modality at an early stage with the hamming embedding of these modalities. The hamming embedding also provides an effective solution for fast retrieval tasks on a large scale dataset. We have evaluated the proposed method on the large-scale ModelNet40 dataset for the tasks of 3D shape classification, single modality and cross-modality retrieval. Comprehensive experiments and comparisons with state-of-the-art methods demonstrate that the proposed approach can achieve superior performance. [ABSTRACT FROM AUTHOR]

Frame rate up-conversion (FRUC) usually suffers from unreliable motion vectors due to the absence of the current frame to be interpolated. In addition, since the majority of video sequences are usually compressed by various coding standards to reduce the data volume, the quality of the generated frames in the FRUC will be further impaired. To address this problem, we proposed two FRUC algorithms based on deep residual network. We first present a deep residual network for the FRUC (DRNFRUC), which consists of feature extraction, feature recursive analysis, and image restoration parts with a skip connection between the input and the output of the network. The proposed DRNFRUC takes the result of an arbitrary existing FRUC method as the input and is able to significantly reduce the edge blurring and blocking artifacts when the motion of the block is violent. In addition, we proposed a deep residual network with weighted convolutional motion compensation (DRNWCMC) for the FRUC, where the convolution operations can be embedded into the motion compensation interpolation (MCI) in any existing MCI-based FRUC method. In DRNWCMC, we first devise two convolutional neural networks corresponding to the forward and backward motion compensated frames, respectively. And then, the adaptive interpolation coefficients for motion compensation are designed as two $1\times1$ convolutional kernels. Finally, the interpolation result of WCMC is fed into another convolutional neural network to further improve the performance. All the parameters involved in the DRNWCMC are trained simultaneously under the same cost function. The experimental results show that the two proposed algorithms can remarkably improve both the objective and subjective quality of the interpolated frames. [ABSTRACT FROM AUTHOR]

Uyghur text localization in images with complex backgrounds is a challenging yet important task for many applications. Generally, Uyghur characters in images consist of strokes with uniform features, and they are distinct from backgrounds in color, intensity, and texture. Based on these differences, we propose aFASTrokekeypoint extractor, which is fast and stroke-specific. Compared with the commonly used MSER detector, FASTroke produces less than twice the amount of components and recognizes at least 10% more characters. While the characters in a line usually have uniform features such as size, color, and stroke width, a component similarity based clustering is presented without component-level classification. It incurs no extra errors by incorporating a component-level classifier while the computing cost is drastically reduced. The experiments show that the proposed method can achieve the best performance on the UICBI-500 benchmark dataset. [ABSTRACT FROM AUTHOR]

Compared with traditional image classification, fine-grained visual categorization is a more challenging task, because it targets to classify objects belonging to the same species, e.g., classify hundreds of birds or cars. In the past several years, researchers have made many achievements on this topic. However, most of them are heavily dependent on the artificial annotations, e.g., bounding boxes, part annotations, and so on. The requirement of artificial annotations largely hinders the scalability and application. Motivated to release such dependence, this paper proposes a robust and discriminative visual description named Automated Bi-level Description (AutoBD). “Bi-level” denotes two complementary part-level and object-level visual descriptions, respectively. AutoBD is “automated,” because it only requires the image-level labels of training images and does not need any annotations for testing images. Compared with the part annotations labeled by the human, the image-level labels can be easily acquired, which thus makes AutoBD suitable for large-scale visual categorization. Specifically, the part-level description is extracted by identifying the local region saliently representing the visual distinctiveness. The object-level description is extracted from object bounding boxes generated with a co-localization algorithm. Although only using the image-level labels, AutoBD outperforms the recent studies on two public benchmark, i.e., classification accuracy achieves 81.6% on CUB-200–2011 and 88.9% on Car-196, respectively. On the large-scale Birdsnap data set, AutoBD achieves the accuracy of 68%, which is currently the best performance to the best of our knowledge. [ABSTRACT FROM PUBLISHER]

Text detection in complex background images is a challenging task for intelligent vehicles. Actually, almost all the widely-used systems focus on commonly used languages while for some minority languages, such as the Uyghur language, text detection is paid less attention. In this paper, we propose an effective Uyghur language text detection system in complex background images. First, a new channel-enhanced maximally stable extremal regions (MSERs) algorithm is put forward to detect component candidates. Second, a two-layer filtering mechanism is designed to remove most non-character regions. Third, the remaining component regions are connected into short chains, and the short chains are extended by a novel extension algorithm to connect the missed MSERs. Finally, a two-layer chain elimination filter is proposed to prune the non-text chains. To evaluate the system, we build a new data set by various Uyghur texts with complex backgrounds. Extensive experimental comparisons show that our system is obviously effective for Uyghur language text detection in complex background images. The F-measure is 85%, which is much better than the state-of-the-art performance of 75.5%. [ABSTRACT FROM PUBLISHER]

Clothing style analysis is a critical step for understanding images of people. To automatically identify the style of clothing that people wear is a challenging task due to various poses of person and large variations for even the same clothing category. Suit as one of the clothing style is a key element in many important activities. In this paper, we propose a novel suits detection method for images of people in unconstrained environments. In order to cope with various human poses, human pose estimation is incorporated. By analyzing the style of clothing, we propose the color features, shape features and statistical features for suits detection. Experiments with four popular classifiers have been conducted to demonstrate that the proposed features are effective and robust. Comparative experiments with Bag of Words (BoW) method demonstrate that the proposed features are superior to BoW which is a popular method for object detection. The proposed method has achieved promising performance over our dataset, which is a challenging web image set with various human poses and diverse styles of clothing. [ABSTRACT FROM AUTHOR]

In traditional image retrieval, images are commonly represented using Bag-of-visual-Words (BoW) built from image local features. However, the lack of spatial and structural information suppresses its performance in applications. In this paper, we introduce a multi-cues description by fusing structural, content and spatial information for partial-duplicate image retrieval. Firstly, we propose a rotation-invariant Local Self-Similarity Descriptor (LSSD), which captures the internal structural layouts in the local textural self-similar regions around interest points. Then, based on the spatial pyramid model, we make use of both LSSD and SIFT to construct an image representation with multi-cues. Finally, we formulate the Semi-Relative Entropy as the distance metric. Comparison experiments with state-of-the-art methods on four popular databases show the efficiency and effectiveness of our approach. [ABSTRACT FROM AUTHOR]

With the development of productivity, people set higher demands on the quality of steel. In recent years, artificial intelligence, especially deep learning-based computer vision technology has attracted great attention, which can be used for detecting steel surface defects such as scratches, patches, and rust spots. However, due to the complexity of the strip steel surface, it is still a challenge to accurately and effectively detect defect regions by the existing defects detection methods. Therefore, we propose a unique saliency model, i.e., deeper feature integration network to highlight the defect regions on the strip steel surface. To be specific, after each encoder stage, we introduce the multiscale global feature extraction module to elevate the multiscale deep features from the encoder. Meanwhile, we deploy the deeper feature extraction module, which contains a bidirectional feature extraction unit, to dig the effective representation for defects. Particularly, the forward one is equipped with a channel-space weighted module and the backward one is equipped with a split attention module. After that, the features from the two branches are progressively integrated by the decoder, yielding the final high-quality saliency maps that give a good depiction of the strip steel surface defects. Extensive experiments are executed on the public dataset, and the comparison results show that our model performs better than the 15 state-of-the-art methods, which proves the effectiveness and superiority of the proposed model. [ABSTRACT FROM AUTHOR]

The challenge of video quality assessment (VQA) modeling for user-generated content (UGC) (i.e., UGC-VQA) is how to accurately extract discriminative features and elaborately quantify interfeature interactions by following the behavior patterns of human eye-brain vision perception. To address this issue, we propose the Deeper Spatial–Temporal Scoring Network (DSTS-Net) to give a precise VQA. Concretely, we first deploy the multiscale feature extraction module to characterize content-aware features accounting for nonlinear reverse hierarchy theory in video perception process, which is not fully considered in the reported UGC-VQA models. Hierarchical handcraft and semantic features are simultaneously considered using content adaptive weighting. Second, we develop a feature integration structure, i.e., deeper gated recurrent unit (DGRU), to fully imitate the interfeature interactions in visionary perception, including feedforward and feedback processes. Third, the dual DGRU structure is employed to further account for interframe interactions of hierarchical features, imitating the nonlinearity of perception as much as possible. Finally, improved pooling is achieved in the local adaptive smoothing module accounting for the temporal hysteresis. Holistic validation of the proposed method on four public challenging UGC-VQA datasets presents a comparable performance over the state-of-the-art no-reference VQA methods, especially our method can give an accurate prediction of the low quality videos with weak temporal correlation. To promote reproducible research and public evaluation, an implementation of our method has been made available online: https://github.com/liu0527aa/DSTS-Net. [ABSTRACT FROM AUTHOR]

Aerial-view geo-localization tends to determine an unknown position through matching the drone-view image with the geo-tagged satellite-view image. This task is mostly regarded as an image retrieval problem. The key underpinning this task is to design a series of deep neural networks to learn discriminative image descriptors. However, existing methods meet large performance drops under realistic weather, such as rain and fog, since they do not take the domain shift between the training data and multiple test environments into consideration. To minor this domain gap, we propose a Multiple-environment Self-adaptive Network (MuSe-Net) to dynamically adjust the domain shift caused by environmental changing. In particular, MuSe-Net employs a two-branch neural network containing one multiple-environment style extraction network and one self-adaptive feature extraction network. As the name implies, the multiple-environment style extraction network is to extract the environment-related style information, while the self-adaptive feature extraction network utilizes an adaptive modulation module to dynamically minimize the environment-related style gap. Extensive experiments on three widely-used benchmarks, i.e. , University-1652, SUES-200, and CVUSA, demonstrate that the proposed MuSe-Net achieves a competitive result for geo-localization in multiple environments. Furthermore, we observe that the proposed method also shows great potential to the unseen extreme weather, such as mixing the fog, rain and snow. • Identifying one key challenge in visual geo-localization: weather and illumination changes. • Presenting MuSe-Net to alleviate the interference caused by environmental changes. • Designing Residual SPADE for efficient training and feature discrimination boosting. • Results on three geo-localization benchmarks confirm the superiority of our MuSe-Net. [ABSTRACT FROM AUTHOR]

The assessment of image is a critical task in computer vision, particularly in a no-referenced context, which presents numerous challenges. Though Deep neural networks have exhibited excellent performance on no-reference quality assessment (NR-IQA), the distortion-aware NR-IQA methods are limited to specific distortion type and struggle to handle realistic distortion scenarios. In this work, we propose a feature rectification and enhancement convolutional neural network namely FREIQA for NR-IQA. Our approach targets to fully utilize the multi-stage semantic features to produce a well fused and rectified score vector for effective image quality regression. Specifically, the multi-stage semantic features extracted by a pre-trained backbone would be rectified with a multi-level channel attention module before integrating to a global score vector. The fused score vector then will be gradually optimized through the perception feature provided by the multi-stage semantic feature, and finally sent to quality regression network to obtain the image quality score. Experimental results on public benchmarks including LIVE, TID2013, CSIQ, LIVEC, KADID-10k, KonIQ-10k and Waterloo exploration database show that our FREIQA achieve the state-of-the-art performance. [ABSTRACT FROM AUTHOR]

This paper introduces a novel video saliency model for salient object detection in videos. Firstly, we generate multi-level deep features via a symmetrical convolutional neural network, in which the inputs are the current frame and the optical flow image. Then, the multi-level deep features are integrated in a hierarchical manner using a fusion network, which deploys attention module to make a selection for deep features. Lastly, the integrated deep feature is combined with the boundary information originated from shallow layer of the feature extraction networks, and the saliency map is generated by the saliency prediction step. The key advantages of our model lie on the attention module, the hierarchical integration and the boundary information, in which the former one acts as weight filter and is used to select the most salient regions in deep features, the middle one gives an effective integration manner for features from different layers and the last one provides well-defined boundaries for saliency map. Extensive experiments are performed on two challenging video dataset, and the experimental results show that our model consistently outperforms the state-of-the-art saliency models in a large margin. [ABSTRACT FROM AUTHOR]

To boost the product quality, numerous saliency-based surface defect detection methods have been devoted to the areas of industrial production, construction consumable, road construction. However, the existing salient object detection (SOD) methods not only consume a significant amount of computing resources but also fail to meet the detection efficiency requirements of enterprises. Therefore, this paper proposes a lightweight semantics-aware multi-level feature interaction network (SMINet), to address the above issues. In the encoder phase, we integrate multiple adjacent level features in the cross-layer feature fusion (CFF) module to alleviate the discrepancy between multi-scale features. In the decoder phase, we first employ the semantic-aware feature extraction (SFE) module to mine the location cues embedded in the high-level features. Afterwards, we introduce the detail-aware context attention (DCA) module based on the attention mechanism to recover more spatial details. Extensive experiments on four surface defect datasets validate that our SMINet outperforms the existing state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The crucial issue in RGBD saliency detection is how to adequately mine and fuse the geometric information and the appearance information contained in depth maps and RGB images, respectively. In this paper, we propose a novel feature aggregation network FANet including a feature extraction module and an aggregation module for RGBD saliency detection. The premier characteristic of FANet is the feature aggregation module consisting of a designed region enhanced module (REM) and a series of deployed hierarchical fusion module (HFM). Specifically, on one hand, the REM provides the powerful capability in differentiating salient objects and background. On the other hand, the HFM is used to gradually integrate high-level semantic information and low-level spatial details, where the K-nearest neighbor graph neural networks (KGNNs) and the non-local module (NLM) are embedded into HFM to dig the geometric information and enhance high-level appearance features, respectively. Extensive experiments on five RGBD datasets show that our model achieves compelling performance against the current 11 state-of-the-art RGBD saliency models. • We propose a novel feature aggregation network (FANet) for RGBD saliency detection. • Region enhanced module REM is used to differentiate salient regions and backgrounds. • Hierarchical fusion module HFM is used to aggregate multi-modal cues. • HFM is supported by the graph neural networks (KGNNs) and the non-local module (NLM). • Extensive experimental results verify the effectiveness of the proposed FANet. [ABSTRACT FROM AUTHOR]

Existing efforts of saliency detection have achieved excellent performance in RGB images, thus to sufficiently exploit existing RGB saliency models and further do some extensions on them, we can transfer existing RGB saliency models to the similar research field, i.e. RGBD saliency detection, by introducing depth cues. Here, we construct a novel RGBD saliency model upon an existing RGB saliency model. To be specific, firstly, our model deploys a depth-guided module to guide the deep features extraction, where the multi-level deep depth features obtained from depth branch are embedded into the backbone network and integrate with multi-level deep RGB features. Secondly, to further promote the performance of our model, we devise a boundary constraint module to elevate the detection accuracy, where the boundary information is compounded by the low-level deep RGB and depth features. Comprehensive experiments are performed on five public RGBD saliency detection datasets, and the experimental results clearly demonstrate the effectiveness and superiority of our model when compared with the state-of-the-art RGBD saliency models. [ABSTRACT FROM AUTHOR]

In RGBD saliency detection research field, RGB and depth cues are generally given the same status by RGBD saliency models. However, they ignore that both modalities are significantly different in inherent attribution so that effective features cannot be drawn from depth maps. In order to address this issue, this paper proposes a novel RGBD saliency model including two key components: the contrast-guided depth feature extraction (CDFE) module and the cross-modal feature integration (CFI) module. Specifically, considering the specific properties of depth information, we first design a targeted CDFE module, which learns multi-level deep depth features by strengthening the depth contrast between foreground and background, to provide multi-level deep depth features. Then, to sufficiently and reasonably integrate multi-level cross-modal features, namely the multi-level deep RGB and depth features, we equip the saliency inference branch with the CFI module, which contains two successive steps, i.e. information enrichment and feature enhancement. Extensive experiments are conducted on five challenging RGBD datasets, and the experimental results clearly demonstrate the effectiveness and superiority of the proposed model against the state-of-the-art RGBD saliency models. [ABSTRACT FROM AUTHOR]