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1.
J Hazard Mater ; 467: 133721, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38341893

RESUMO

Harmful algal blooms (HABs) are challenging to recognize because of their striped and uneven biomass distributions. To address this issue, a refined deep-learning algorithm termed HAB-Ne was developed for the recognition of HABs in GF-1 Wide Field of View (WFV) images using Noctiluca scintillans algal bloom as an example. First, a pretrained image super-resolution model was integrated to improve the spatial resolution of the GF-1 WFV images and minimize the impact of mixed pixels caused by the strip distribution. Side-window convolution was also explored to enhance the edge features of HABs and minimize the effects of uneven biomass distribution. In addition, a convolutional encoder-decoder network was constructed for threshold-free HAB recognition to address the dependence on thresholds in existing methods. HAB-Net effectively recognized HABs from GF-1 WFV images, achieving an average precision of 90.1% and an F1-score of 0.86. HAB-Net showed more fine-grained recognition results than those of existing methods, with over 4% improvement in the F1-Score, especially in the marginal areas of HAB distribution. The algorithm demonstrated its effectiveness in recognizing HABs in different marine environments, such as the Yellow Sea, East China Sea, and northern Vietnam. Additionally, the algorithm was proven suitable for detecting the macroalga Sargassum. This study demonstrates the potential of deep-learning-based fine-grained recognition of HABs, which can be extended to the recognition of other fine-scale and strip-distributed objects, such as oil spills and Ulva prolifera.


Assuntos
Aprendizado Profundo , Dinoflagellida , Algas Comestíveis , Ulva , Proliferação Nociva de Algas , Algoritmos
2.
Materials (Basel) ; 14(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573144

RESUMO

Polymer-composite materials have the characteristics of light weight, high load, corrosion resistance, heat resistance, and high oil resistance. In particular, graphene composite has better electrical conductivity and mechanical performance. However, the raw materials of graphene composite are processed into semi-finished products, directly affecting their performance and service life. The electromagnetic pulse compaction was initially studied to get the product Graphene/PEKK composite powder. Simultaneously, spark plasma sintering was used to get the bars to determine the electrical conductivity of Graphene/PEKK composite. On the basis of this result, conducting Graphene/PEKK composite powder can be processed by electromagnetic pulse compaction. Finite element numerical analysis was used to obtain process parameters during the electromagnetic pulse compaction. The results show that discharge voltage and discharge capacitance influence on the magnetic force, which is a main moulding factor affecting stress, strain and density distribution on the specimen during electromagnetic pulse compaction in a few microseconds.

3.
ACS Omega ; 5(51): 33445-33454, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33403306

RESUMO

Self-sustaining smoldering combustion is a promising technology for treating sewage sludge from wastewater treatment plants because of its low energy inputs. Proper use or disposal of the resulting ashes requires thorough characterization of their properties, including the content of total organic carbon (TOC). Here, we develop a two-step method for quantifying TOC in the raw ashes from sewage sludge smoldering combustion. The first step is to thermally treat the raw ashes at 500 °C in N2 for 1 h, followed by ultimate analysis of both the raw ashes and the thermally treated ashes. This enables the quantification of carbon released during thermal treatment. The second step is nonisothermal thermogravimetric analysis (TGA) of the thermally treated ashes, in which the samples are heated to 900 °C at 10 °C/min in air. The weight losses at 310-500 °C are confirmed to be caused by organic carbon oxidation, allowing us to determine the contents of carbon retained in the thermally treated ashes. The sums of these two portions of carbon represent the contents of TOC in the raw ashes, which are ∼0.85-6.52 wt % (dry basis), depending on their locations and particle sizes. The two-step (thermal treatment-TGA) method is validated via a method that includes acid washing of the thermally treated ashes, ultimate analysis of the acid-washed ashes, and TOC analysis of the leachates. The two-step method is simple and accurate and, importantly, provides thorough information on the thermal behavior of the raw and thermally treated ashes.

4.
IEEE Trans Cybern ; 50(1): 297-309, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30273168

RESUMO

This paper proposes an ensemble decision approach which combines global and local features of e-mails together to detect spam effectively. In the proposed method, a special feature construction method named term space partition (TSP) is utilized to divide the whole term space into several subspaces and adopt different feature construction strategies on each of them, respectively. This method can make each term play a distinct and important role when conducting detection. This method is utilized and extended by introducing the sliding window technique to extract local features from e-mails. The global classifier and local classifiers are constructed on a global feature vector set and local feature vector sets, respectively, and together make the ensemble decision by adopting the voting technique. The principles of the TSP-based approach and mechanism of the ensemble decision method are presented in detail. Five different and standard benchmark corpora are applied to experiments for performance evaluation of this proposed method. Comprehensive experimental results show that the proposed method brings significant performance improvement and better robustness on the basis of the TSP-based approach. In addition, the proposed method outperforms the current prevalent and state-of-the-art approaches, especially when a comprehensive consideration of performance, efficiency, and robustness is taken. This endows it with flexible capability and adaptivity in the real-world applications.

5.
Med Sci Monit ; 24: 6102-6106, 2018 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-30173243

RESUMO

BACKGROUND We explored the possible relationship between Modic changes (MCs) and sagittal parameters of the cervical spine. MATERIAL AND METHODS We enrolled 150 patients with cervical MC on the magnetic resonance imaging (MRI) scans in the MC (+) group and divided them into 3 sub-groups with 50 patients each: the MC1 sub-group, the MC2 sub-group, and the MC3 sub-group. Another 150 healthy subjects receiving routine health examinations were also enrolled in the study as the MC (-) group. The sagittal parameters in the cervical spine were measured and compared and multiple logistic regression analysis was performed to analyze the risk factor for the occurrence of MC. RESULTS Four cervical sagittal parameters were measured and compared between all the enrolled groups, including neck tilt (NT), T1 slope (T1s), thoracic inlet angle (TIA), and Cobb C2-C7. The results confirmed that the parameter of Cobb C2-C7 was much smaller in the MC(+) group when compared with that in the MC(-) group (P<0.05), while no significant differences were detected between the MC(+) and MC(-) groups for the parameters of NT, T1 T1s, and TIA (P>0.05). Multiple logistic regression analysis showed that Cobb C2-C7 (less than 8.5°) could be regarded as the risk factor for the occurrence of MC, and the receiver operating characteristic (ROC) curve showed that moderate diagnostic significance was obtained with an area under curve (AUC) of 0.82. CONCLUSIONS The present study demonstrated that Cobb C2-C7 (less than 8.5°) is a potential risk factor for the development of MC.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Pescoço/patologia , Osteoartrite da Coluna Vertebral/diagnóstico por imagem , Curva ROC , Fatores de Risco , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia
6.
Arch Virol ; 162(12): 3903-3905, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28828700

RESUMO

In this study, we isolated a mycobacteriophage infecting Mycobacterium smegmatis mc2155 from a soil sample collected in Shandong Province in China. This phage was named Shandong1. It is a member of the family Siphoviridae with an isometric head and a long tail. Its genome was found to be 60,618 bp long with 67.46% G + C content and 96 putative protein-coding genes. No tRNA-encoding genes were identified. Comparative genomics analysis showed that the mycobacteriophage Shandong1 should be considered a member of a new species in mycobacteriophage cluster K.


Assuntos
Genoma Viral , Micobacteriófagos/genética , Micobacteriófagos/isolamento & purificação , Mycobacterium smegmatis/virologia , Análise de Sequência de DNA , Siphoviridae/genética , Siphoviridae/isolamento & purificação , Composição de Bases , China , Micobacteriófagos/classificação , Micobacteriófagos/ultraestrutura , Filogenia , Siphoviridae/classificação , Siphoviridae/ultraestrutura , Microbiologia do Solo , Vírion/ultraestrutura
7.
Zhongguo Gu Shang ; 28(11): 1056-9, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26757537

RESUMO

OBJECTIVE: To explore the clinical effects of one-stage hemiarthroplasty in treating fresh subtrochanteric fracture combined with old femoral neck fracture. METHODS: From October 2003 to October 2013, 7 patients with fresh subtrochanteric fracture and old femoral neck fracture were treated with hemiarthroplasty in one stage. There were 5 males and 2 females, aged from 69 to 80 years old with an average of 74.5 years. According to the Garden classification, 2 cases were type IV and 5 cases were type V. According to the A0 classification of subtrochanteric fracture, all cases were type A1 (long oblique femoral subtrochanteric fractures). Biological coating long handle femoral prosthesis was used in the patients. The hip joint functions were assessed according to Charnley scoring system after all hemiarthroplasty. RESULTS: Seven patients were followed up from 12 to 24 months with an average of 18 months. There were 1 case with urinary system infection and 1 case with deep venous thrombosis. Of all, 5 cases recovered the walk ability at 6 months after operation and 2 cases could walk with the help of the crutch at 1 year after operation. According to Charnley scoring system to assess the hip joint function, the total Charnley scores reached 15.0±2.5, and 4 cases got an excellent results, 2 good, 1 fair. CONCLUSION: Arthroplasty through anterolateral approach can obtain satisfactory clinical effects in treating fresh subtrochanteric fracture combined with old femoral neck fracture, it has advantages of good joint stability, little pain, less complication, quickly recover, early activities on fields.


Assuntos
Artroplastia/métodos , Fraturas do Colo Femoral/cirurgia , Fraturas do Quadril/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
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