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1.
Sensors (Basel) ; 24(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38339757

RESUMO

This study introduces a multilayer perceptron (MLP) error compensation method for real-time camera orientation estimation, leveraging a single vanishing point and road lane lines within a steady-state framework. The research emphasizes cameras with a roll angle of 0°, predominant in autonomous vehicle contexts. The methodology estimates pitch and yaw angles using a single image and integrates two Kalman filter models with inputs from image points (u, v) and derived angles (pitch, yaw). Performance metrics, including avgE, minE, maxE, ssE, and Stdev, were utilized, testing the system in both simulator and real-vehicle environments. The outcomes indicate that our method notably enhances the accuracy of camera orientation estimations, consistently outpacing competing techniques across varied scenarios. This potency of the method is evident in its adaptability and precision, holding promise for advanced vehicle systems and real-world applications.

2.
Environ Sci Pollut Res Int ; 31(6): 9333-9346, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38191729

RESUMO

As an inland dryland lake basin, the rivers and lakes within the Lake Bosten basin provide scarce but valuable water resources for a fragile environment and play a vital role in the development and sustainability of the local societies. Based on the Google Earth Engine (GEE) platform, combined with the geographic information system (GIS) and remote sensing (RS) technology, we used the index WI2019 to extract and analyze the water body area changes of the Bosten Lake basin from 2000 to 2021 when the threshold value is -0.25 and the slope mask is 8°. The driving factors of water body area changes were also analyzed using the partial least squares-structural equation model (PLS-SEM). The result shows that in the last 20 years, the area of water bodies in the Bosten Lake basin generally fluctuated during the dry, wet, and permanent seasons, with a decreasing trend from 2000 to 2015 and an increasing trend between 2015 and 2019 followed by a steadily decreasing trend afterward. The main driver of the change in wet season water bodies in the Bosten Lake basin is the climatic factors, with anthropogenic factors having a greater influence on the water body area of dry season and permanent season than that of wet season. Our study achieved an accurate and convenient extraction of water body area and drivers, providing up-to-date information to fully understand the spatial and temporal variation of surface water body area and its drivers in the basin, which can be used to effectively manage water resources.


Assuntos
Monitoramento Ambiental , Lagos , Lagos/química , Água , Qualidade da Água , Rios/química , China
3.
Mar Pollut Bull ; 196: 115653, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37879130

RESUMO

Chromophoric dissolved organic matter (CDOM) occupies a critical part in biogeochemistry and energy flux of aquatic ecosystems. CDOM research spans in many fields, including chemistry, marine environment, biomass cycling, physics, hydrology, and climate change. In recent years, a series of remarkable research milestone have been achieved. On the basis of reviewing the research process of CDOM, combined with a bibliometric analysis, this study aims to provide a comprehensive review of the development and applications of remote sensing in monitoring CDOM from 2003 to 2022. The findings show that remote sensing data plays an important role in CDOM research as proven with the increasing number of publications since 2003, particularly in China and the United States. Primary research areas have gradually changed from studying absorption and fluorescence properties to optimization of remote sensing inversion models in recent years. Since the composition of oceanic and freshwater bodies differs significantly, it is important to choose the appropriate inversion method for different types of water body. At present, the monitoring of CDOM mainly relies on a single sensor, but the fusion of images from different sensors can be considered a major research direction due to the complex characteristics of CDOM. Therefore, in the future, the characteristics of CDOM will be studied in depth inn combination with multi-source data and other application models, where inversion algorithms will be optimized, inversion algorithms with low dependence on measured data will be developed, and a transportable inversion model will be built to break the regional limitations of the model and to promote the development of CDOM research in a deeper and more comprehensive direction.


Assuntos
Matéria Orgânica Dissolvida , Monitoramento Ambiental , Monitoramento Ambiental/métodos , Ecossistema , Tecnologia de Sensoriamento Remoto , China , Bibliometria , Espectrometria de Fluorescência/métodos
4.
Micromachines (Basel) ; 14(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37512665

RESUMO

This paper investigates the performance of deep convolutional spiking neural networks (DCSNNs) trained using spike-based backpropagation techniques. Specifically, the study examined temporal spike sequence learning via backpropagation (TSSL-BP) and surrogate gradient descent via backpropagation (SGD-BP) as effective techniques for training DCSNNs on the field programmable gate array (FPGA) platform for object classification tasks. The primary objective of this experimental study was twofold: (i) to determine the most effective backpropagation technique, TSSL-BP or SGD-BP, for deeper spiking neural networks (SNNs) with convolution filters across various datasets; and (ii) to assess the feasibility of deploying DCSNNs trained using backpropagation techniques on low-power FPGA for inference, considering potential configuration adjustments and power requirements. The aforementioned objectives will assist in informing researchers and companies in this field regarding the limitations and unique perspectives of deploying DCSNNs on low-power FPGA devices. The study contributions have three main aspects: (i) the design of a low-power FPGA board featuring a deployable DCSNN chip suitable for object classification tasks; (ii) the inference of TSSL-BP and SGD-BP models with novel network architectures on the FPGA board for object classification tasks; and (iii) a comparative evaluation of the selected spike-based backpropagation techniques and the object classification performance of DCSNNs across multiple metrics using both public (MNIST, CIFAR10, KITTI) and private (INHA_ADAS, INHA_KLP) datasets.

5.
Food Chem ; 356: 129736, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33831823

RESUMO

Variations in the biochemical composition and nutritional quality with annual changes in gonad development were investigated to identify the optimal harvesting time of C. hongkongensis. The glycogen levels in the mantle, muscle, and gonad-visceral mass were significantly lower in June than in December, associated with changes in the expressions of ChGS and ChGP. Protein content consistently exceeded 52% of dry weight. The only significant change in protein levels was an increase between April and June in the gonad-visceral mass, which was associated with the gonadal transition from proliferation to maturation. Moreover, C. hongkongensis consistently had a well-balanced essential amino acid profile, meeting the essential amino acid requirements of preschool children. The lipid content and fatty acid composition of C. hongkongensis varied with the reproductive cycle, but the omega-3:omega-6 ratio was consistently higher than those of C. gigas and C. virginica. In summary, the optimal harvest time of C. hongkongensis was during the inactive stage of most gonads (from August to February at Beihai).


Assuntos
Crassostrea/metabolismo , Valor Nutritivo , Estações do Ano , Animais , Crassostrea/fisiologia , Ácidos Graxos/metabolismo , Glicogênio/metabolismo , Gônadas/metabolismo , Proteínas/metabolismo , Reprodução
6.
Mar Life Sci Technol ; 3(4): 463-473, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37073264

RESUMO

The production of an all-triploid population by mating tetraploid males with diploid females is the best and most fundamental method for the large-scale production of triploid oysters. Obtaining a stable tetraploid population is essential for guaranteed production in industrialized triploid cultivation. C. hongkongensis and C. sikamea are important oyster breeding species in southern China, and have great economic value. However, there are not any published data on inducing tetraploid C. hongkongensis or C. sikamea. Therefore, we investigated tetraploid induction in these two oyster species by inhibiting the PB1 release in diploid fertilized eggs using Cytochalasin B (CB) under 31 °C, 15 ‰ salinity. The results confirmed that the optimal tetraploid induction conditions for C. hongkongensis were a CB concentration of 0.50 mg/L with induction starting at 9.0 min after fertilization, and stopping at 21.0 min after fertilization; the induction efficiency index reached 0.123 under these conditions. The optimal tetraploid induction conditions for C. sikamea were a CB concentration of 0.50 mg/L, with induction starting at 7.5 min after fertilization and stopping at 18 min after fertilization; the induction efficiency index could be as high as 0.281 under these conditions. However, we confirmed that the tetraploid rate decreased with larval growth, and no tetraploids were detected in the juvenile period of either C. hongkongensis or C. sikamea. This may be attributed to the very low survival of the tetraploid larvae induced by this method, especially as most tetraploid larvae died during the first three days. In summary, it is simple to directly induce tetraploid C. hongkongensis and C. sikamea larvae by inhibiting the PB1 release of diploid zygotes, but the low survival rate makes it challenging to obtain viable juvenile tetraploids.

7.
AJR Am J Roentgenol ; 215(3): 595-602, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32569515

RESUMO

OBJECTIVE. The purpose of this study was to investigate the correlation between iodine concentration (IC) derived from spectral CT and angiogenesis and the relationships between IC and clinical-pathologic features associated with lung cancer prognosis. SUBJECTS AND METHODS. Sixty patients with lung cancer were enrolled and underwent spectral CT. The IC, IC difference (ICD), and normalized IC (NIC) of tumors were measured in the arterial phase, venous phase (VP), and delayed phase. The microvessel densities (MVDs) of CD34-stained specimens were evaluated. Correlation analysis was performed for IC and MVD. The relationships between the IC index showing the best correlations with MVD and clinical-pathologic findings of pathologic types, histologic differentiation, tumor size, lymph node status, pathologic TNM stage, and intratumoral necrosis were investigated. RESULTS. The mean (± IQR) MVD of all tumors was 42.00 ± 27.50 vessels per field at ×400 magnification, with two MVD distribution types. The MVD of lung cancer correlated positively with the IC, ICD, and NIC on three-phase contrast-enhanced scanning (r range, 0.581-0.800; all p < 0.001), and the IC in the VP showed the strongest correlation with MVD (r = 0.800; p < 0.001). The correlations between IC and MVD, ICD and MVD, and NIC and MVD varied depending on whether the same scanning phase or same IC index was used. The IC in the VP showed statistically significant differences in the pathologic types of adenocarcinoma and squamous cell carcinoma, histologic differentiation, tumor size, and status of intratumoral necrosis of lung cancer (p < 0.05), but was not associated with nodal metastasis and pathologic TNM stages (p > 0.05). CONCLUSION. IC indexes derived from spectral CT, especially the IC in the VP, were useful indicators for evaluating tumor angiogenesis and prognosis.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Iohexol , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Prognóstico , Estudos Prospectivos , Carga Tumoral
8.
Fish Shellfish Immunol ; 98: 122-129, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31917320

RESUMO

Caspase 3 plays an important role in apoptotic pathways and contributes to maintaining the homeostasis of the immune system in organisms. The structure, functions, and characteristics of caspase 3 have been extensively investigated in many species, but the research is scarce when it comes to bivalves, particularly oysters. In this study, we identified and cloned a previously unknown caspase 3 gene, named ChCas 3, in C. hongkongensis. The full-length cDNA of ChCas 3 was 1562 bp and included a 175 bp 5'-untranslated region (UTR), a 141 bp 3'-UTR and a 1245 bp open reading frame (ORF) that encoded a polypeptide of 415 amino acids. Similar to caspase 3 in other species, ChCas 3 has a pro-domain, a conserved cysteine active site, a large p20 subunit and a small p10 subunit. Our findings demonstrated the expression of ChCas 3 in all the eight tissues via tissue-specific expression assays with the highest expression in haemocytes. ChCas 3 was confirmed to be expressed throughout the larval development stages, and fluorescence from pEGFP-N1-ChCas 3 was found to be distributed throughout the entire HEK293T cell. In addition, the relative expression of ChCas 3 significantly enhanced in hemocytes post bacterial stimulation, and overexpression of ChCas 3 led to upregulation of the transcriptional activity of NF-κB and p53 reporter genes in HEK293T cells, which indicated that it was involved in innate immune responses. Finally, the apoptosis rate of the haemocytes declined considerably compared with that of the control group after the expression of ChCas 3 was successfully silenced by dsRNA, corroborating its sentinel role in apoptosis. This study provides comprehensive underpinning evidences, affirming caspase 3 crucial role against bacterial infection and apoptosis in C. hongkongensis.


Assuntos
Apoptose/genética , Caspase 3/genética , Caspase 3/imunologia , Crassostrea/genética , Crassostrea/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , Células HEK293 , Hemócitos/metabolismo , Humanos
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