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1.
IEEE Trans Neural Netw Learn Syst ; 30(11): 3287-3299, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30714931

RESUMEN

As nontechnical losses in power systems have recently become a global concern, electricity fraud detection models attracted increasing academic interest. The wide application of smart meters has offered more possibility to detecting fraud from user's consumption patterns. However, the performances of existing consumption-based electricity fraud detection models are still not satisfactory enough for practice, partly due to their limited ability to handle high-dimensional data. In this paper, a deep-learning-based model is developed for detecting electricity fraud in the advanced metering infrastructure, namely, the multitask feature extracting fraud detector (MFEFD). The deep architecture has brought MFEFD a powerful ability to handle high-dimensional input, through which consumption patterns inside load profiles can be effectively extracted. Another challenge is that the insufficiency of labeled data has restricted the generalization of existing models since they are mostly based on supervised learning and labeled data. MFEFD is trained in a semisupervised manner, in which multitask training was implemented to combine the supervised and unsupervised training, so that both the knowledge from unlabeled and labeled data can be made use of. Real-world-data-based case studies have demonstrated MFEFD's high detection performance, robustness, privacy preservation, and practicability.

2.
Magn Reson Med Sci ; 18(1): 53-61, 2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-29848919

RESUMEN

PURPOSE: This study aimed to determine whether whole-tumor histogram analysis of normalized cerebral blood volume (nCBV) and apparent diffusion coefficient (ADC) for contrast-enhancing lesions can be used to differentiate between glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL). METHODS: From 20 patients, 9 with PCNSL and 11 with GBM without any hemorrhagic lesions, underwent MRI, including diffusion-weighted imaging and dynamic susceptibility contrast perfusion-weighted imaging before surgery. Histogram analysis of nCBV and ADC from whole-tumor voxels in contrast-enhancing lesions was performed. An unpaired t-test was used to compare the mean values for each type of tumor. A multivariate logistic regression model (LRM) was performed to classify GBM and PCNSL using the best parameters of ADC and nCBV. RESULTS: All nCBV histogram parameters of GBMs were larger than those of PCNSLs, but only average nCBV was statistically significant after Bonferroni correction. Meanwhile, ADC histogram parameters were also larger in GBM compared to those in PCNSL, but these differences were not statistically significant. According to receiver operating characteristic curve analysis, the nCBV average and ADC 25th percentile demonstrated the largest area under the curve with values of 0.869 and 0.838, respectively. The LRM combining these two parameters differentiated between GBM and PCNSL with a higher area under the curve value (Logit (P) = -21.12 + 10.00 × ADC 25th percentile (10-3 mm2/s) + 5.420 × nCBV mean, P < 0.001). CONCLUSION: Our results suggest that whole-tumor histogram analysis of nCBV and ADC combined can be a valuable objective diagnostic method for differentiating between GBM and PCNSL.


Asunto(s)
Neoplasias del Sistema Nervioso Central/diagnóstico por imagen , Volumen Sanguíneo Cerebral/fisiología , Imagen de Difusión por Resonancia Magnética/métodos , Glioblastoma/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Linfoma/diagnóstico por imagen , Humanos , Curva ROC
3.
Eur J Radiol ; 106: 100-105, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30150030

RESUMEN

PURPOSE: This study aimed to compare the quality of abdominal CT angiography (CTA) images obtained using conventional reconstruction algorithms with those obtained using a novel iterative algorithm (forward projected model-based iterative reconstruction solution, FIRST) for evaluating arteries in the abdomen. MATERIALS AND METHODS: Abdominal CTA images from 60 patients (M:F = 27:33; mean age, 62.4 ± 16.7 years) were reconstructed using three algorithms - filtered back projection (FBP), adaptive iterative dose reduction 3D (AIDR 3D), and FIRST. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in the abdominal aorta, celiac trunk, superior mesenteric, renal, and right hepatic arteries were objectively evaluated via region-of-interest analysis and compared using the one-way analysis of variance test. Two radiologists independently scored and selected the best (score 3), second best (score 2), and the worst (score 1) images based on the visual image quality of peripheral arteries. Wilcoxon signed rank test was used for comparing image quality scores. RESULTS: FIRST and AIDR 3D significantly reduced image noise compared with FBP (P < 0.001). SNR and CNR were significantly higher with AIDR 3D and FIRST than with FBP reconstruction (P < 0.001), with FIRST displaying the highest CNR (14.31 ± 4.17) for the right hepatic artery than the other two methods (P < 0.05). Both radiologists scored FIRST images as having the best image quality among the three methods for peripheral abdominal artery evaluation (3.0 ± 0.0, P < 0.001). CONCLUSION: FIRST reconstruction yielded superior abdominal CTA images as compared with FBP or AIDR 3D reconstruction.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Radiografía Abdominal/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Relación Señal-Ruido
4.
J Comput Assist Tomogr ; 42(4): 648-654, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29787496

RESUMEN

OBJECTIVE: The aim of this study was to quantitatively compare the reduction in beam hardening artifact (BHA) and variance in computed tomography (CT) numbers of virtual monochromatic energy (VME) images obtained with 3 dual-energy computed tomography (DECT) systems at a given radiation dose. METHODS: Five different iodine concentrations were scanned using dual-energy and single-energy (120 kVp) modes. The BHA and CT number variance were evaluated. RESULTS: For higher iodine concentrations, 40 and 80 mgI/mL, BHA on VME imaging was significantly decreased when the energy was higher than 50 keV (P = 0.003) and 60 keV (P < 0.001) for GE, higher than 80 keV (P < 0.001) and 70 keV (P = 0.002) for Siemens, and higher than 40 keV (P < 0.001) and 60 keV (P < 0.001) for Toshiba, compared with single-energy CT imaging. CONCLUSIONS: Virtual monochromatic energy imaging can decrease BHA and improve CT number accuracy in different dual-energy computed tomography systems, depending on energy levels and iodine concentrations.


Asunto(s)
Artefactos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Estudios de Evaluación como Asunto , Fantasmas de Imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos
5.
Jpn J Radiol ; 35(10): 613-621, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28879406

RESUMEN

PURPOSE: This study aimed to compare the tumor volume definition using conventional magnetic resonance (MR) and 11C-methionine positron emission tomography (MET/PET) images in the differentiation of the pre-operative glioma grade by using whole-tumor histogram analysis of normalized cerebral blood volume (nCBV) maps. MATERIALS AND METHODS: Thirty-four patients with histopathologically proven primary brain low-grade gliomas (n = 15) and high-grade gliomas (n = 19) underwent pre-operative or pre-biopsy MET/PET, fluid-attenuated inversion recovery, dynamic susceptibility contrast perfusion-weighted magnetic resonance imaging, and contrast-enhanced T1-weighted at 3.0 T. The histogram distribution derived from the nCBV maps was obtained by co-registering the whole tumor volume delineated on conventional MR or MET/PET images, and eight histogram parameters were assessed. RESULTS: The mean nCBV value had the highest AUC value (0.906) based on MET/PET images. Diagnostic accuracy significantly improved when the tumor volume was measured from MET/PET images compared with conventional MR images for the parameters of mean, 50th, and 75th percentile nCBV value (p = 0.0246, 0.0223, and 0.0150, respectively). CONCLUSION: Whole-tumor histogram analysis of CBV map provides more valuable histogram parameters and increases diagnostic accuracy in the differentiation of pre-operative cerebral gliomas when the tumor volume is derived from MET/PET images.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Volumen Sanguíneo Cerebral/fisiología , Glioma/diagnóstico por imagen , Glioma/patología , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Mapeo Encefálico/métodos , Neoplasias Encefálicas/irrigación sanguínea , Radioisótopos de Carbono , Femenino , Glioma/irrigación sanguínea , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Metionina , Persona de Mediana Edad , Clasificación del Tumor , Reproducibilidad de los Resultados , Carga Tumoral , Adulto Joven
6.
J Agric Food Chem ; 64(12): 2591-603, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-26978261

RESUMEN

The bacterial community and the metabolic activities involved at the flavor-forming stage during the fermentation of shrimp sauce were investigated using metatranscriptome and 16S rRNA gene sequencings. Results showed that the abundance of Tetragenococcus was 95.1%. Tetragenococcus halophilus was identified in 520 of 588 transcripts annotated in the Nr database. Activation of the citrate cycle and oxidative phosphorylation, along with the absence of lactate dehydrogenase gene expression, in T. halophilus suggests that T. halophilus probably underwent aerobic metabolism during shrimp sauce fermentation. The metabolism of amino acids, production of peptidase, and degradation of limonene and pinene were very active in T. halophilus. Carnobacterium, Pseudomonas, Escherichia, Staphylococcus, Bacillus, and Clostridium were also metabolically active, although present in very small populations. Enterococcus, Abiotrophia, Streptococcus, and Lactobacillus were detected in metatranscriptome sequencing, but not in 16S rRNA gene sequencing. Many minor taxa showed no gene expression, suggesting that they were in dormant status.


Asunto(s)
Enterococcaceae/genética , ARN Ribosómico 16S/genética , Animales , Monoterpenos Bicíclicos , Ciclohexenos/metabolismo , Limoneno , Monoterpenos/metabolismo , Péptido Hidrolasas/metabolismo , Mariscos , Terpenos/metabolismo
7.
Radiol Case Rep ; 10(1): 1025, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27408657

RESUMEN

Rotation-induced vertebral artery compression and occlusion with the outcome of cerebellar infarction (as opposed to the outcome of transient ischemia from hemodynamic insufficiency, known as bow hunter's stroke) is extremely rare. We report a 40-year-old male who suffered from ipsilateral neck-rotation-induced right vertebral artery compression and occlusion that resulted in right cerebellar infarction. In most reported cases, the rotation-compressed vertebral artery is located at the C1-2 level; however, our patient's compressed artery was located at the C6-7 level as demonstrated clearly by 3-dimensional CT angiography. This case report is based on a literature review and an investigation of the likely factors of this specific incident via the patient's personal details, clinical course, and diagnostic images.

8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 19(4): 377-9, 2003 Jul.
Artículo en Chino | MEDLINE | ID: mdl-15163390

RESUMEN

AIM: To study the activation effect of BCR/ABL antigen on T cells from CML patients mediated by protein transduction domain (PTD). METHODS: The fused plasmid containing PTD gene and b3a2 bcr/abl gene of CML was constructed by genetic engineering technique and was expressed in E.coli. The PBMCs from CML patients were stimulated in-vitro with purified PTD-BCR/ABL antigen and then expression of the activation antigen CD25 on CD8(+) and CD4(+) T cells after stimulation was detected by flow cytometry (FCM). RESULTS: After stimulation with 100 mg/L of PTD-BCR/ABL antigen (final concentration) for 4 days in-vitro, CD8(+) T cells were activated in 5 of 10 CML patients and CD4(+) T cells were activated in 2 of 10 patients. Both CD8(+) and CD4(+) T cells were activated simultaneously in one of them. However, neither CD4(+) nor CD8(+) T cells was activated in BCR/ABL antigen stimulation group as control. CONCLUSION: Using a PTD-mediated antigen transduction system, exogenous BCR/ABL antigen can be transferred into APCs and be processed and presented onto surface of APCs to activate Ag-specific CD8(+) and CD4(+) T cells in-vitro. The strategy outlined in this paper may provide a new approach for priming Ag-specific CD8(+) and CD4(+) T cells in-vitro and immunotherapy of CML.


Asunto(s)
Linfocitos T CD8-positivos , Leucemia Mielógena Crónica BCR-ABL Positiva , Linfocitos T CD4-Positivos/inmunología , Antígenos CD8 , Linfocitos T CD8-positivos/metabolismo , Proteínas de Fusión bcr-abl/genética , Humanos , Estructura Terciaria de Proteína
9.
Zhonghua Xue Ye Xue Za Zhi ; 23(1): 5-8, 2002 Jan.
Artículo en Chino | MEDLINE | ID: mdl-12015079

RESUMEN

OBJECTIVE: To construct a vector containing protein transduction domain (PTD) and bcr/abl fusion gene of chronic myelogenous leukemia and express PTD-bcr/abl fusion protein in E. Coli. METHODS: DNA fragment encoding PTD was synthesized and fused to PCR-amplified bcr/abl gene fragment, then inserted into plasmid pET-16b to get the expression vector pEPb containing PTD-bcr/abl fusion gene, which was transfected and expressed in E. Coli LB21. PTD-bcr/abl fusion protein was purified by affinity chromatography. RESULTS: 523 bp bcr/abl fusion gene was effectively amplified. The PTD-bcr/abl gene sequencing showed the same sequence as scheduled. The fusion peptide was successfully expressed in E. Coli and purified. CONCLUSION: The results may provide a new PTD-bcr/abl fusion peptide for the immunotherapy of CML.


Asunto(s)
Proteínas de Fusión bcr-abl/genética , Productos del Gen tat/genética , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Proteínas de Fusión bcr-abl/metabolismo , Expresión Génica , Productos del Gen tat/metabolismo , Vectores Genéticos/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 9(3): 220-222, 2001 Sep.
Artículo en Chino | MEDLINE | ID: mdl-12578593

RESUMEN

To study the alteration of the cell cycle during the differentiation of human myeloid leukemia cell line HL-60 induced with all trans-retinoic acid (RA), the flow cytometry was used to assay the various phases of cell cycle in HL-60 cells treated with RA. The results showed: (1) S + G(2)/M phase proportion kept relative invariability during the 48 hours incubation of HL-60 cells with RA, however, the proportion alteration of S-phase cells was associated with the RA concentrations. At 10(-6) mol/L RA, the proportion of S-phase cells appeared a temporarily increasing peak followed by persistent decrease of S-phase proportion. At 10(-5) mol/L RA, S-phase cell proportion only appeared the persistent decreasing tendency. (2) Re-culture of HL-60 cells without RA showed the decrease of S + G(2)/M and S-phase cells was associated with the increase of differentiated cells, but not all HL-60 cells were triggered into differentiation at the same time. Once the cells start to differentiate, even if there is no RA presence, the HL-60 cells were still differentiated until maturation. In conclusion, HL-60 cells are able to differentate and maturate after exposure to RA for a period of time. S-phase proportion is related to the concentrations of RA. Once the cells start to differentiate, even if there is no RA presence, the HL-60 cells still differentiatiated until maturation.

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