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1.
IEEE Trans Pattern Anal Mach Intell ; 46(6): 4331-4347, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38265906

RESUMO

Individuals have unique facial expression and head pose styles that reflect their personalized speaking styles. Existing one-shot talking head methods cannot capture such personalized characteristics and therefore fail to produce diverse speaking styles in the final videos. To address this challenge, we propose a one-shot style-controllable talking face generation method that can obtain speaking styles from reference speaking videos and drive the one-shot portrait to speak with the reference speaking styles and another piece of audio. Our method aims to synthesize the style-controllable coefficients of a 3D Morphable Model (3DMM), including facial expressions and head movements, in a unified framework. Specifically, the proposed framework first leverages a style encoder to extract the desired speaking styles from the reference videos and transform them into style codes. Then, the framework uses a style-aware decoder to synthesize the coefficients of 3DMM from the audio input and style codes. During decoding, our framework adopts a two-branch architecture, which generates the stylized facial expression coefficients and stylized head movement coefficients, respectively. After obtaining the coefficients of 3DMM, an image renderer renders the expression coefficients into a specific person's talking-head video. Extensive experiments demonstrate that our method generates visually authentic talking head videos with diverse speaking styles from only one portrait image and an audio clip.


Assuntos
Expressão Facial , Movimentos da Cabeça , Fala , Gravação em Vídeo , Humanos , Fala/fisiologia , Movimentos da Cabeça/fisiologia , Algoritmos , Cabeça , Imageamento Tridimensional/métodos , Face/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos
2.
Mol Biotechnol ; 65(11): 1796-1808, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36790659

RESUMO

Gastric cancer (GC) has been a common tumor type with high mortality. Distal metastasis is one of the main causes of death in GC patients, which is also related to poor prognosis. The mRNA profiles and clinical information of GC patients were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. Univariate Cox and LASSO Cox analyses were used to screen the optimal metastasis-related genes (MRGs) to establish a prognostic Risk Score model for GC patients. The nomogram was used to visualize the Risk Score and predict the 1-, 3-, 5-year survival rate. The immune cell infiltration was analyzed by CIBERSORT and the ratio of immune-stromal component was calculated by the ESTIMATE algorithm. A total of 142 differentially expressed genes were identified between metastatic and non-metastatic GC samples. The optimal 8 genes, comprising GAMT (guanidinoacetate N-methyltransferase), ABCB5 (ATP-binding cassette subfamily B member 5), ITIH3 (inter-alpha-trypsin inhibitor heavy chain 3), GDF3 (growth differentiation factor 3), VSTM2L (V-set and transmembrane domain-containing 2 like), CIDEA (cell death inducing DFFA like effector a), NPTX1 (neuronal pentraxin-1), and UMOD (uromodulin), were further screened to establish a prognostic Risk Score, which proved to be an independent prognostic factor. Patients in high-risk group had a poor prognosis. There were significant differences in the proportion of 11 tumor-infiltrating immune cells between high-risk and low-risk subgroups. In addition, the StromalScore, ImmuneScore, and ESTIMATEScore in high-risk group were higher than those in low-risk group, indicating that the tumor microenvironment of the high-risk group was more complex. A Risk Score model based on eight metastasis-related genes could clearly distinguish the prognosis of GC patients. The poor prognosis of patients with high-Risk Score might be associated with the complex tumor microenvironments.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Fatores de Risco , Morte Celular , Microambiente Tumoral/genética
3.
IEEE Trans Neural Netw Learn Syst ; 30(11): 3444-3457, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30762569

RESUMO

In this paper, a novel model-free adaptive control (MFAC) algorithm based on a dual successive projection (DuSP)-MFAC method is proposed, and it is analyzed using the introduced DuSP method and the symmetrically similar structures of the controller and its parameter estimator of MFAC. Then, the proposed DuSP-MFAC scheme is successfully implemented in an autonomous car "Ruilong" for the lateral tracking control problem via converting the trajectory tracking problem into a stabilization problem by using the proposed preview-deviation-yaw angle. This MFAC-based lateral tracking control method was tested and demonstrated satisfactory performance on real roads in Fengtai, Beijing, China, and through successful participation in the Chinese Smart Car Future Challenge Competition held in 2015 and 2016.

4.
Sensors (Basel) ; 16(3): 280, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26927108

RESUMO

A high-performance differential global positioning system (GPS)  receiver with real time kinematics provides absolute localization for driverless cars. However, it is not only susceptible to multipath effect but also unable to effectively fulfill precise error correction in a wide range of driving areas. This paper proposes an accurate GPS-inertial measurement unit (IMU)/dead reckoning (DR) data fusion method based on a set of predictive models and occupancy grid constraints. First, we employ a set of autoregressive and moving average (ARMA) equations that have different structural parameters to build maximum likelihood models of raw navigation. Second, both grid constraints and spatial consensus checks on all predictive results and current measurements are required to have removal of outliers. Navigation data that satisfy stationary stochastic process are further fused to achieve accurate localization results. Third, the standard deviation of multimodal data fusion can be pre-specified by grid size. Finally, we perform a lot of field tests on a diversity of real urban scenarios. The experimental results demonstrate that the method can significantly smooth small jumps in bias and considerably reduce accumulated position errors due to DR. With low computational complexity, the position accuracy of our method surpasses existing state-of-the-arts on the same dataset and the new data fusion method is practically applied in our driverless car.

5.
J Neurophysiol ; 114(6): 3296-305, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26445865

RESUMO

The brain often has to make decisions based on information stored in working memory, but the neural circuitry underlying working memory is not fully understood. Many theoretical efforts have been focused on modeling the persistent delay period activity in the prefrontal areas that is believed to represent working memory. Recent experiments reveal that the delay period activity in the prefrontal cortex is neither static nor homogeneous as previously assumed. Models based on reservoir networks have been proposed to model such a dynamical activity pattern. The connections between neurons within a reservoir are random and do not require explicit tuning. Information storage does not depend on the stable states of the network. However, it is not clear how the encoded information can be retrieved for decision making with a biologically realistic algorithm. We therefore built a reservoir-based neural network to model the neuronal responses of the prefrontal cortex in a somatosensory delayed discrimination task. We first illustrate that the neurons in the reservoir exhibit a heterogeneous and dynamical delay period activity observed in previous experiments. Then we show that a cluster population circuit decodes the information from the reservoir with a winner-take-all mechanism and contributes to the decision making. Finally, we show that the model achieves a good performance rapidly by shaping only the readout with reinforcement learning. Our model reproduces important features of previous behavior and neurophysiology data. We illustrate for the first time how task-specific information stored in a reservoir network can be retrieved with a biologically plausible reinforcement learning training scheme.


Assuntos
Memória de Curto Prazo , Modelos Neurológicos , Reforço Psicológico , Animais , Humanos , Neurônios/fisiologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiologia
6.
Int J Neural Syst ; 24(7): 1450026, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25112716

RESUMO

In this study, an event-related complexity (ERC) analysis method is proposed and used to explore the neural correlates of facial attractiveness detection in the context of a cognitive experiment. The ERC method gives a quantitative index for measuring the diverse brain activation properties that represent the neural correlates of event-related responses. This analysis reveals distinct effects of facial attractiveness processing and also provides further information that could not have been achieved from event-related potential alone.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Estética , Face , Percepção Visual/fisiologia , Algoritmos , Potenciais Evocados , Estudos de Viabilidade , Feminino , Humanos , Julgamento/fisiologia , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Processamento de Sinais Assistido por Computador , Adulto Jovem
7.
J Integr Neurosci ; 11(4): 477-87, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23351053

RESUMO

Facial attractiveness has been an interesting topic in cognitive psychology due to its key role in human communication and experience. The evaluation of attractiveness is adjusted by many factors including gender differences and cultural biases. In this paper, event-related potential (ERP) activity was recorded in an oddball paradigm from 10 Chinese men and 10 Chinese women who judged attractiveness of faces. Participants were told to detect faces with neutral expression and judge their attractiveness among a train of neutral objects that were presented more frequently than the faces. The ERP analyses showed that there was enhanced detection over early (P1, N170, P2, N300) and late (P3b) components in both genders. This suggests that a biased electrophysiological response to attractive faces compared to unattractive faces could indicate the involvement of emotion and reward pathways in judging facial attractiveness. Specifically, there were delayed P1 and P3b latencies in response to attractive faces with slower response times in men compared to women. From an evolutionary perspective, this may suggest that men attribute more value to facial appearances, especially attractive features, than women do, as evidenced by their cognitive load while processing attractive faces compared to unattractive faces.


Assuntos
Beleza , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Caracteres Sexuais , Eletroencefalografia , Face , Feminino , Humanos , Masculino , Adulto Jovem
8.
BMC Bioinformatics ; 10 Suppl 1: S36, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19208137

RESUMO

BACKGROUND: Non-coding RNA (ncRNA) genes do not encode proteins but produce functional RNA molecules that play crucial roles in many key biological processes. Recent genome-wide transcriptional profiling studies using tiling arrays in organisms such as human and Arabidopsis have revealed a great number of transcripts, a large portion of which have little or no capability to encode proteins. This unexpected finding suggests that the currently known repertoire of ncRNAs may only represent a small fraction of ncRNAs of the organisms. Thus, efficient and effective prediction of ncRNAs has become an important task in bioinformatics in recent years. Among the available computational methods, the comparative genomic approach seems to be the most powerful to detect ncRNAs. The recent completion of the sequencing of several major plant genomes has made the approach possible for plants. RESULTS: We have developed a pipeline to predict novel ncRNAs in the Arabidopsis (Arabidopsis thaliana) genome. It starts by comparing the expressed intergenic regions of Arabidopsis as provided in two whole-genome high-density oligo-probe arrays from the literature with the intergenic nucleotide sequences of all completely sequenced plant genomes including rice (Oryza sativa), poplar (Populus trichocarpa), grape (Vitis vinifera), and papaya (Carica papaya). By using multiple sequence alignment, a popular ncRNA prediction program (RNAz), wet-bench experimental validation, protein-coding potential analysis, and stringent screening against various ncRNA databases, the pipeline resulted in 16 families of novel ncRNAs (with a total of 21 ncRNAs). CONCLUSION: In this paper, we undertake a genome-wide search for novel ncRNAs in the genome of Arabidopsis by a comparative genomics approach. The identified novel ncRNAs are evolutionarily conserved between Arabidopsis and other recently sequenced plants, and may conduct interesting novel biological functions.


Assuntos
Arabidopsis/genética , Biologia Computacional/métodos , RNA não Traduzido/genética , Proteínas de Arabidopsis/genética , Sequência Conservada , Bases de Dados Genéticas , Genoma de Planta , Reprodutibilidade dos Testes , Análise de Sequência de RNA
9.
Sensors (Basel) ; 9(4): 2836-50, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22574048

RESUMO

Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS) and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes' location. Finally, an improved sequence-based localization algorithm is presented to complete precise localization for mobile targets. The proposed method is tested through simulations with 100 nodes, outdoor experiments with 15 ZigBee physical nodes, and the experiments in the mine gas explosion laboratory with 12 ZigBee nodes. Experimental results show that our method has better localization accuracy and is more robust in underground mines.

10.
Sensors (Basel) ; 9(10): 8007-30, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22408491

RESUMO

Energy constraints restrict the lifetime of wireless sensor networks (WSNs) with battery-powered nodes, which poses great challenges for their large scale application. In this paper, we propose a family of collaborative distributed scheduling approaches (CDSAs) based on the Markov process to reduce the energy consumption of a WSN. The family of CDSAs comprises of two approaches: a one-step collaborative distributed approach and a two-step collaborative distributed approach. The approaches enable nodes to learn the behavior information of its environment collaboratively and integrate sleep scheduling with transmission scheduling to reduce the energy consumption. We analyze the adaptability and practicality features of the CDSAs. The simulation results show that the two proposed approaches can effectively reduce nodes' energy consumption. Some other characteristics of the CDSAs like buffer occupation and packet delay are also analyzed in this paper. We evaluate CDSAs extensively on a 15-node WSN testbed. The test results show that the CDSAs conserve the energy effectively and are feasible for real WSNs.

11.
IEEE Trans Neural Netw ; 18(5): 1364-75, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18220186

RESUMO

This paper proposes a scale-free highly clustered echo state network (SHESN). We designed the SHESN to include a naturally evolving state reservoir according to incremental growth rules that account for the following features: (1) short characteristic path length, (2) high clustering coefficient, (3) scale-free distribution, and (4) hierarchical and distributed architecture. This new state reservoir contains a large number of internal neurons that are sparsely interconnected in the form of domains. Each domain comprises one backbone neuron and a number of local neurons around this backbone. Such a natural and efficient recurrent neural system essentially interpolates between the completely regular Elman network and the completely random echo state network (ESN) proposed by Jaeger et al. We investigated the collective characteristics of the proposed complex network model. We also successfully applied it to challenging problems such as the Mackey-Glass (MG) dynamic system and the laser time-series prediction. Compared to the ESN, our experimental results show that the SHESN model has a significantly enhanced echo state property and better performance in approximating highly complex nonlinear dynamics. In a word, this large scale dynamic complex network reflects some natural characteristics of biological neural systems in many aspects such as power law, small-world property, and hierarchical architecture. It should have strong computing power, fast signal propagation speed, and coherent synchronization.


Assuntos
Algoritmos , Modelos Teóricos , Redes Neurais de Computação , Simulação por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Artigo em Inglês | MEDLINE | ID: mdl-17369645

RESUMO

Biological processes are always carried out through large numbers of genes (and their products) and these activities are often organized into different cellular pathways: sets of genes that cooperate to finish specific biological functions. Owing to the development of microarray technology and its ability to simultaneously measure the expression of thousands of genes, effective algorithms to reveal biologically significant pathways are possible. However, some open problems such as large amount of noise in microarrays and the fact that most biological processes are overlapping and active only on partial conditions pose great challenges to researchers. In this paper, we proposed a novel approach to identify overlapping pathways via extracting partial expression profiles from coherent cliques of clusters scattered on different conditions. We firstly decompose gene expression data into highly overlapping segments and partition genes into clusters in each segment; then we organize all the resulting clusters as a cluster graph and search coherent cliques of clusters; finally we extract expression profiles from coherent cliques and shape biological pathways as genes consistent with these profiles. We compare our algorithm with several recent models and the experimental results justify the superiorities of our approach: robustly identifying overlapping pathways in arbitrary set of conditions and consequently discovering more biologically significant pathways in terms of enrichment of gene functions.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica , Peptídeos/química , Proteômica/métodos , Algoritmos , Análise por Conglomerados , Proteínas Fúngicas/química , Modelos Estatísticos , Análise Serial de Proteínas
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