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1.
Radiology ; 310(1): e231611, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38193838

RESUMEN

Background CT-defined visceral pleural invasion (VPI) is an important indicator of prognosis for non-small cell lung cancer (NSCLC). However, there is a lack of studies focused on small subpleural NSCLCs (≤30 mm). Purpose To identify CT features predictive of VPI in patients with subpleural NSCLCs 30 mm or smaller. Materials and Methods This study is a retrospective review of patients enrolled in the Initiative for Early Lung Cancer Research on Treatment (IELCART) at Mount Sinai Hospital between July 2014 and February 2023. Subpleural nodules 30 mm or smaller were classified into two groups: a pleural-attached group and a pleural-tag group. Preoperative CT features suggestive of VPI were evaluated for each group separately. Multivariable logistic regression analysis adjusted for sex, age, nodule size, and smoking status was used to determine predictive factors for VPI. Model performance was analyzed with the area under the receiver operating characteristic curve (AUC), and models were compared using Akaike information criterion (AIC). Results Of 379 patients with NSCLC with subpleural nodules, 37 had subsolid nodules and 342 had solid nodules. Eighty-eight patients (22%) had documented VPI, all in solid nodules. Of the 342 solid nodules (46% in male patients, 54% in female patients; median age, 71 years; IQR: 66, 76), 226 were pleural-attached nodules and 116 were pleural-tag nodules. VPI was more frequent for pleural-attached nodules than for pleural-tag nodules (31% [69 of 226] vs 16% [19 of 116], P = .005). For pleural-attached nodules, jellyfish sign (odds ratio [OR], 21.60; P < .001), pleural thickening (OR, 6.57; P < .001), and contact surface area (OR, 1.05; P = .01) independently predicted VPI. The jellyfish sign led to a better VPI prediction (AUC, 0.84; 95% CI: 0.78, 0.90). For pleural-tag nodules, multiple tags to different pleura surfaces enabled independent prediction of VPI (OR, 9.30; P = .001). Conclusions For patients with solid NSCLC (≤30 mm), CT predictors of VPI were the jellyfish sign, pleural thickening, contact surface area (pleural-attached nodules), and multiple tags to different pleura surfaces (pleural-tag nodules). © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Nishino in this issue.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Femenino , Masculino , Anciano , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Pleura/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Hospitales , Tomografía Computarizada por Rayos X
2.
Radiology ; 310(1): e231219, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38165250

RESUMEN

Background Pulmonary noncalcified nodules (NCNs) attached to the fissural or costal pleura with smooth margins and triangular or lentiform, oval, or semicircular (LOS) shapes at low-dose CT are recommended for annual follow-up instead of immediate workup. Purpose To determine whether management of mediastinal or diaphragmatic pleura-attached NCNs (M/DP-NCNs) with the same features as fissural or costal pleura-attached NCNs at low-dose CT can follow the same recommendations. Materials and Methods This retrospective study reviewed chest CT examinations in participants from two databases. Group A included 1451 participants who had lung cancer that was first present as a solid nodule with an average diameter of 3.0-30.0 mm. Group B included 345 consecutive participants from a lung cancer screening program who had at least one solid nodule with a diameter of 3.0-30.0 mm at baseline CT and underwent at least three follow-up CT examinations. Radiologists reviewed CT images to identify solid M/DP-NCNs, defined as nodules 0 mm in distance from the mediastinal or diaphragmatic pleura, and recorded average diameter, margin, and shape. General descriptive statistics were used. Results Among the 1451 participants with lung cancer in group A, 163 participants (median age, 68 years [IQR, 61.5-75.0 years]; 92 male participants) had 164 malignant M/DP-NCNs 3.0-30.0 mm in average diameter. None of the 164 malignant M/DP-NCNs had smooth margins and triangular or LOS shapes (upper limit of 95% CI of proportion, 0.02). Among the 345 consecutive screening participants in group B, 146 participants (median age, 65 years [IQR, 59-71 years]; 81 female participants) had 240 M/DP-NCNs with average diameter 3.0-30.0 mm. None of the M/DP-NCNs with smooth margins and triangular or LOS shapes were malignant after a median follow-up of 57.8 months (IQR, 46.3-68.1 months). Conclusion For solid M/DP-NCNs with smooth margins and triangular or LOS shapes at low-dose CT, the risk of lung cancer is extremely low, which supports the recommendation of Lung Imaging Reporting and Data System version 2022 for annual follow-up instead of immediate workup. © RSNA, 2024 See also the editorial by Goodman and Baruah in this issue.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Femenino , Masculino , Humanos , Anciano , Detección Precoz del Cáncer , Neoplasias Pulmonares/diagnóstico por imagen , Pleura , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
3.
Nano Lett ; 23(22): 10196-10204, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37926956

RESUMEN

Low-power electronic devices play a pivotal role in the burgeoning artificial intelligence era. The study of such devices encompasses low-subthreshold swing (SS) transistors and neuromorphic devices. However, conventional field-effect transistors (FETs) face the inherent limitation of the "Boltzmann tyranny", which restricts SS to 60 mV decade-1 at room temperature. Additionally, FET-based neuromorphic devices lack sufficient conductance states for highly accurate neuromorphic computing due to a narrow memory window. In this study, we propose a pioneering PZT-enabled MoS2 floating gate transistor (PFGT) configuration, demonstrating a low SS of 46 mV decade-1 and a wide memory window of 7.2 V in the dual-sweeping gate voltage range from -7 to 7 V. The wide memory window provides 112 distinct conductance states for PFGT. Moreover, the PFGT-based artificial neural network achieves an outstanding facial-recognition accuracy of 97.3%. This study lays the groundwork for the development of low-SS transistors and highly energy efficient artificial synapses utilizing two-dimensional materials.

4.
Radiology ; 304(2): 437-447, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35438565

RESUMEN

Background Bronchiectasis is associated with loss of lung function, substantial use of health care resources, and increased morbidity and mortality in people with cardiopulmonary diseases. Purpose To assess the frequency and severity of bronchiectasis and related clinical findings of participants in a low-dose CT (LDCT) screening program. Materials and Methods The Early Lung and Cardiac Action Program (ELCAP) bronchiectasis score (range, 0-42; higher values indicate more severe bronchiectasis) was developed to facilitate bronchiectasis assessment. This quantitative scoring system screened participants based on accumulated knowledge and improved CT imaging capabilities. Secondary review of LDCT studies from smokers aged 40-90 years was performed when they were initially enrolled in the prospective Mount Sinai ELCAP screening study between 2010 and 2019. Medical records were reviewed to identify associated respiratory symptoms and acute respiratory events during the 2 years after LDCT. Logistic regression analysis was performed to examine factors associated with bronchiectasis. Results LDCT studies of 2191 screening participants (mean age, 65 years ± 9; 1140 [52%] women) were obtained, and bronchiectasis was identified in 504 (23%) participants. Median ELCAP bronchiectasis score was 12 (interquartile range, 9-16). Bronchiectasis was most common in the lower lobes for all participants, and lower lobe prevalence was greater with higher ELCAP score (eg, 91% prevalence with an ELCAP score of 16-42). In the fourth quartile, however, midlung involvement was higher compared with lower lung involvement (128 of 131 participants [98%] vs 122 of 131 participants [93%]). Bronchiectasis was more frequent with greater age (odds ratio [OR] = 2.0 per decade; 95% CI: 1.7, 2.4); being a former smoker (OR = 1.33; 95% CI: 1.01, 1.73); and having self-reported chronic obstructive pulmonary disease (OR = 1.38; 95% CI: 1.02, 1.88), an elevated hemidiaphragm (OR = 4; 95% CI: 2, 11), or consolidation (OR = 5; 95% CI: 3, 11). It was less frequent in overweight (OR = 0.7; 95% CI: 0.5, 0.9) or obese (OR = 0.6; 95% CI: 0.4, 0.8) participants. Two years after baseline LDCT, respiratory symptoms, acute respiratory events, and respiratory events that required hospitalization were more frequent with increasing severity of the ELCAP bronchiectasis score (P < .005 for all trends). Conclusion Prevalence of bronchiectasis in smokers undergoing low-dose CT screening was high, and respiratory symptoms and acute events were more frequent with increasing severity of the Early Lung and Cardiac Action Program Bronchiectasis score. © RSNA, 2022 See also the editorial by Verschakelen in this issue.


Asunto(s)
Bronquiectasia , Neoplasias Pulmonares , Anciano , Bronquiectasia/diagnóstico por imagen , Bronquiectasia/epidemiología , Detección Precoz del Cáncer , Femenino , Humanos , Neoplasias Pulmonares/epidemiología , Masculino , Estudios Prospectivos , Tomografía Computarizada por Rayos X
5.
Sensors (Basel) ; 22(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36236243

RESUMEN

We propose a novel pose estimation method that can predict the full-body pose from six inertial sensors worn by the user. This method solves problems encountered in vision, such as occlusion or expensive deployment. We address several complex challenges. First, we use the SRU network structure instead of the bidirectional RNN structure used in previous work to reduce the computational effort of the model without losing its accuracy. Second, our model does not require joint position supervision to achieve the best results of the previous work. Finally, since sensor data tend to be noisy, we use SmoothLoss to reduce the impact of inertial sensors on pose estimation. The faster deep inertial poser model proposed in this paper can perform online inference at 90 FPS on the CPU. We reduce the impact of each error by more than 10% and increased the inference speed by 250% compared to the previous state of the art.

6.
Radiology ; 301(3): 724-731, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34546130

RESUMEN

Background Solid costal pleura-attached noncalcified nodules (CP-NCNs) less than 10.0 mm with lentiform, oval, or semicircular (LOS) or triangular shapes and smooth margins on baseline low-dose CT scans from the Mount Sinai Early Lung and Cardiac Action Program (MS-ELCAP) were reviewed, and it was determined that they can be followed up at the first annual screening rather than having a shorter-term work-up. Purpose To determine whether the same criteria could be used for solid CP-NCNs newly identified at annual screening examinations. Materials and Methods With use of the same MS-ELCAP database, all new solid CP-NCNs measuring 30.0 mm or less were identified at 4425 annual screening examinations between 2010 and 2019. In addition, to ensure that no malignant CP-NCNs met the criteria, all solid malignant CP-NCNs of 30.0 mm or less in the International Early Lung Cancer Action Program, or I-ELCAP, database of 111 102 annual screening examinations from the 76 participating institutions between 1992 and 2019 were identified; Mount Sinai is one of these institutions. All identified solid CP-NCNs were reviewed-with the radiologists blinded to diagnosis-for shape (triangular, LOS, polygonal, round, or irregular), margin (smooth or nonsmooth), pleural attachment (broad or narrow), and the presence of emphysema and/or fibrosis within 10.0 mm of each CP-NCN. Intra- and interreader readings were performed, and agreements were determined by using the B-statistic. Results Of the 76 new solid CP-NCNs, 21 were lung cancers. Benign CP-NCNs were smaller than malignant ones (median diameter, 4.2 mm vs 11 mm; P < .001), had a different shape distributions, more frequently had smooth margins (67% vs 14%; P < .001), and less frequently had emphysema (38% vs 81%; P = .003) or fibrosis (3.6% vs 19%; P = .045) within a 10.0 mm radius. All 22 solid CP-NCNs less than 10.0 mm in average diameter with triangular or LOS shapes and smooth margins were benign, and none of the 21 solid malignant CP-NCNs had these characteristics. Intra- and interobserver agreement for triangular or LOS-shaped CP-NCNs with smooth margins was almost perfect (0.77 and 0.69, respectively). Conclusion The same follow-up recommendation developed for baseline costal pleura-attached noncalcified nodules (CP-NCNs) can be used for CP-NCNs newly identified at annual screening rounds. © RSNA, 2021.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Pleura/diagnóstico por imagen , Estudios Retrospectivos
7.
Radiology ; 297(3): 710-718, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33021893

RESUMEN

Background Pulmonary nodule features have been used to differentiate benign from malignant nodules. Purpose To determine the frequency of solid noncalcified nodules attached to the costal pleura (CP-NCNs) at baseline low-dose CT and to identify key features of benignity. Materials and Methods A retrospective review was performed of baseline low-dose CT scans obtained in 8730 participants in the Mount Sinai Early Lung and Cardiac Action Program screening cohort between 1992 and 2019. Participants with one or more solid CP-NCNs between 3.0 mm and 30.0 mm in average diameter were included. For each CP-NCN, the size, location, shape (lentiform, oval, or semicircular [LOS]; triangular; polygonal; round; or irregular), margin (smooth or nonsmooth), and attachment to the costal pleura (broad or narrow) were documented. The manifestation of emphysema and fibrosis within a 10-mm radius of the CP-NCN was determined. Multivariable logistic regression analysis, with synthetic minority oversampling techniques, was used. Results The 569 eligible participants (average age, 62 years ± 9 [standard deviation]; 343 women) had 943 solid CP-NCNs, of which 934 (99.0%) were benign and nine (1.0%) were malignant. Multivariable analysis showed that five shapes could be consolidated into three (LOS and/or triangular, round and/or polygonal, and irregular shape); pleural attachment was not a significant independent predictor (odds ratio, 1.24; P = .70); and interaction terms of size with shape (odds ratio, 0.73; P = .005) and margin were significant (odds ratio, 0.80; P = .001). All 603 CP-NCNs less than 10.0 mm with LOS or triangular shapes and smooth margins were benign. Conclusion All baseline noncalcified solid nodules attached to the costal pleura less than 10.0 mm in average diameter with lentiform, oval, semicircular, or triangular shapes and smooth margins were benign; thus, for these nodules, an annual repeat scan in 1 year, rather than a more immediate work-up, is recommended. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Godoy in this issue.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Pleura/diagnóstico por imagen , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Nódulo Pulmonar Solitario/patología
8.
Eur Radiol ; 30(12): 6847-6857, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32725329

RESUMEN

OBJECTIVES: Smoking is a major risk factor for both cardiovascular disease (CVD) and lung cancer. Aortic valve calcification (AVC) and coronary artery calcification (CAC) are both due to atherosclerotic disease. We aim to investigate whether AVC on low-dose CT (LDCT) predicts death from CVD in smokers beyond that provided by CAC. METHODS: We reviewed a prospective cohort of 8618 smokers enrolled in LDCT screening for lung cancer in New York State between June 2000 and December 2005. As of December 2009, 169 of the 643 deaths were due to CVD; median follow-up time was 96.4 months. Visual AVC was assessed as being absent (AVC = 0) or present (AVC > 0). CAC ordinal scores of 0-12 were categorized into three validated prognostic categories (0, 1-3, and 4-12). Cox proportional hazards regression analysis was used to assess whether AVC > 0 increased the risk of CVD death, after adjustment for CAC categories and other risk factors. RESULTS: The prevalence of AVC significantly increased (p < 0.0001) with the increasing severity of the CAC categories; Pearson, Spearman, and Kendall's correlation coefficients showed a significant correlation between AVC and CAC with r = 0.29, ρ = 0.32, and τB = 0.28 (all p values < 0.0001), respectively. CAC and AVC were significant predictors of CVD death when considered alone using multivariable Cox regression analysis (adjusted HR of CAC = 1.57, p = 0.04; adjusted HR of AVC = 1.39, p = 0.045). When AVC > 0 and CAC ≥ 4, the hazard ratio was 2.35 (95%CI 1.57-3.50) compared with the reference group of AVC = 0 and CAC < 4, when adjusted for other risk factors. CONCLUSIONS: The presence of AVC identified on LDCT is a significant predictor of future CVD death, particularly for those with ordinal CAC score ≥ 4. KEY POINTS: • Aortic valve calcification (AVC) and coronary artery calcification (CAC) are both due to atherosclerotic disease. The prevalence of AVC in lung cancer screening cohort significantly increased with the increasing severity of CAC. • CAC and AVC were significant predictors of cardiovascular disease (CVD) death when considered alone. Participants who underwent lung cancer screening with AVC > 0 and CAC ≥ 4 had more than a 2-fold increased risk of CVD death than the group with AVC = 0 and CAC < 4, when adjusted for other risk factors.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Calcinosis/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Anciano , Válvula Aórtica/diagnóstico por imagen , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Fumadores , Tomografía Computarizada por Rayos X
9.
Eur Radiol ; 30(5): 2658-2668, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32040729

RESUMEN

OBJECTIVES: To evaluate risk factors for prevalence and progression of aortic valve calcification (AVC) in lung cancer screening participants and also to assess the sensitivity and reliability of visual AVCs on low-dose CT (LDCT) for predicting aortic stenosis (AS) in high-risk smokers. METHODS: We reviewed 1225 consecutive participants in annual LDCT screening for lung cancer at the Mount Sinai Hospital between 2010 and 2017. Sensitivity and specificity of moderate/severe AVC score on LDCT to identify AS on echocardiogram were calculated for 126 participants who had both within 12 months. Using regression analyses, risk factors for AVC at baseline, for progression, and for new AVC on annual rounds of screening were identified. Reliability of AVC assessment on LDCT was assessed by comparing visual AVC scores (1) with standard-dose, electrocardiography (ECG)-gated CT for 31 participants who had both within 12 months and (2) with Agatston scores of 1225 participants and by determining (3) the intra-reader agreement of 1225 participants. RESULTS: Visual AVC scores on LDCT had substantial agreement with the severity of AS on echocardiography and substantial inter-observer and excellent intra-observer agreement. Sensitivity and specificity of moderate/severe visual AVC scores for moderate/severe AS on echocardiogram were 100% and 94%, respectively. Significant predictors for baseline AVC were male sex (OR = 2.52), age (OR10 years = 2.87), and coronary artery calcification score (OR = 1.18), the significant predictor for AVC progression after baseline was pack-years of smoking (HR10 packyears = 1.14), and significant predictors for new AVC on annual LDCT were male sex (HR = 1.51), age (HR10 years = 2.17), CAC (HR = 1.09)  and BMI (HR = 1.06). CONCLUSIONS: AVC scores on LDCT should be documented, especially in lung cancer screening program. KEY POINTS: • LDCT screening for lung cancer provides an opportunity to identify lung cancer and cardiovascular disease in asymptomatic smokers. • Visual aortic valve calcification scores could be reliably evaluated on LDCT and had substantial agreement with the severity of aortic valve stenosis on echocardiography. • Sensitivity and specificity of moderate/severe visual AVC scores on LDCT for moderate/severe AS on echocardiogram were 100% and 94%, respectively.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Calcinosis/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Factores de Edad , Anciano , Enfermedad de la Arteria Coronaria/epidemiología , Detección Precoz del Cáncer , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Factores Sexuales , Calcificación Vascular/diagnóstico por imagen
11.
Med Sci Monit ; 25: 8260-8268, 2019 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-31678984

RESUMEN

BACKGROUND The association between serum vitamin D level and vertebral fracture (VFx) remains controversial. The purpose of this study was to determine whether serum 25-hydroxy vitamin D (25(OH)D) level is associated with osteoporotic thoracolumbar junction VFx in elderly patients. MATERIAL AND METHODS From Jan 2013 to Dec 2017, this retrospective case-control study included 534 patients with primary osteoporotic thoracolumbar junction VFx (T10-L2) and 569 elderly orthopedic patients with back pain (without osteoporotic VFx) as controls. Serum 25(OH)D levels were measured and the association with osteoporotic VFx was analyzed. Other clinical data, including BMI, comorbidities, and bone mineral density (BMD), were also collected and compared between these 2 groups. RESULTS It was shown that 25(OH)D levels were significantly lower in patients with T10-L2 VFx than in control patients. Among 534 VFx patients, 417 (78.1%) patients showed grade 2-3 fracture. Serum 25(OH)D levels were significantly related to affected vertebral numbers and VFx severities. The VFx risk was 28% lower (OR=0.72, 95% CI 0.62-0.83) per increased SD in serum 25(OH)D. Compared with the 1st quartile (mean 25(OH)D: 29.67±6.18 nmol/L), the VFx risk was significantly lower in the 3rd (mean 25(OH)D: 60.91±5.12nmol/L) and 4th quartiles (mean 25(OH)D: 103.3±44.21nmol/L), but not in the 2nd quartile (mean 25(OH)D: 45.40±3.95 nmol/L). In contrast, the VFx risk was significantly increased in the 1st quartile (OR=1.87, 95% CI 1.42-2.45) compared with the 2nd-4th quartiles. CONCLUSIONS Vitamin D deficiency/insufficiency was associated with risk of osteoporotic thoracolumbar junction vertebral fractures in elderly patients.


Asunto(s)
Fracturas Osteoporóticas/etiología , Deficiencia de Vitamina D/metabolismo , Vitamina D/metabolismo , Anciano , Anciano de 80 o más Años , Densidad Ósea , Estudios de Casos y Controles , Femenino , Humanos , Vértebras Lumbares/metabolismo , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/sangre , Estudios Retrospectivos , Factores de Riesgo , Fracturas de la Columna Vertebral/etiología , Columna Vertebral , Vértebras Torácicas/metabolismo , Vitamina D/análogos & derivados , Vitamina D/sangre , Vitamina D/farmacología , Deficiencia de Vitamina D/sangre
12.
Appl Opt ; 58(26): 7035-7041, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31503972

RESUMEN

This paper introduces radiative cooling metamaterial use in engineering thermal radiation based on metal-multi-dielectric-metal (MMDM) structure. The measured average absorption of the MMDM from 15° to 75° in the "atmosphere window" is 0.81, and the absorption range of the structure hardly changes with the incident angles. Without considering solar radiation, at the thermal conductivity of 6.9 W·m-2·K-1, the surface temperature is 10.8°C lower than the ambient temperature (300 K), and the cooling power is 102 W·m-2. Importantly, when the surface temperature is higher than the ambient temperature, this radiative cooler can lower the surface temperature in engineering thermal radiation with a higher thermal conductivity at the same cooling power.

13.
Radiology ; 286(2): 502-511, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29206594

RESUMEN

Purpose To assess the diagnostic accuracy of magnetic resonance (MR) imaging for differentiating stage T1 or lower tumors from stage T2 or higher tumors and to analyze the influence of different imaging protocols in patients with bladder cancer. Materials and Methods A systematic literature search for original diagnostic studies was performed in PubMed, Medline, the Cochrane Library, and Web of Science. The methodologic quality of each study was evaluated by two independent reviewers who used the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Data necessary to complete 2 × 2 tables were obtained, and patient, study, and imaging characteristics were extracted. Statistical analysis included data pooling, heterogeneity testing, sensitivity analyses, and forest plot construction. Results Seventeen studies (1449 patients with bladder cancer) could be analyzed. The pooled sensitivity and specificity of MR imaging were 0.90 (95% confidence interval [CI]: 0.83, 0.94) and 0.88 (95% CI: 0.77, 0.94), respectively, for differentiating tumors staged T1 or lower from those staged T2 or higher. Diffusion-weighted imaging and use of higher field strengths (3 T) improved sensitivity (0.92; 95% CI: 0.86, 0.96) and specificity (0.96; 95% CI: 0.93, 0.98). Conclusion This meta-analysis demonstrated high diagnostic performance of MR imaging for differentiating T1 or lower tumors from T2 or higher tumors in patients with bladder cancer. Higher field strength (3 T) and the use of diffusion-weighted imaging can slightly help improve sensitivity and specificity. © RSNA, 2017.


Asunto(s)
Neoplasias de la Vejiga Urinaria/patología , Humanos , Imagen por Resonancia Magnética/normas , Estadificación de Neoplasias , Curva ROC , Sensibilidad y Especificidad
14.
J Magn Reson Imaging ; 47(2): 391-400, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28640538

RESUMEN

PURPOSE: To evaluate the utility of the whole-lesion histogram apparent diffusion coefficient (ADC) for characterizing the heterogeneity of mucinous breast carcinoma (MBC) and to determine which ADC metrics may help to best differentiate subtypes of MBC. MATERIALS AND METHODS: This retrospective study involved 52 MBC patients, including 37 pure MBC (PMBC) and 15 mixed MBC (MMBC). The PMBC patients were subtyped into PMBC-A (20 cases) and PMBC-B (17 cases) groups. All patients underwent preoperative diffusion-weighted imaging (DWI) at 1.5T and the whole-lesion ADC assessments were generated. Histogram-derived ADC parameters were compared between PMBC vs. MMBC and PMBC-A vs. PMBC-B, and receiver operating characteristic (ROC) curve analysis was used to determine optimal histogram parameters for differentiating these groups. RESULTS: The PMBC group exhibited significantly higher ADC values for the mean (P = 0.004), 25th (P = 0.004), 50th (P = 0.004), 75th (P = 0.006), and 90th percentiles (P = 0.013) and skewness (P = 0.021) than did the MMBC group. The 25th percentile of ADC values achieved the highest area under the curve (AUC) (0.792), with a cutoff value of 1.345 × 10-3 mm2 /s, in distinguishing PMBC and MMBC. The PMBC-A group showed significantly higher ADC values for the mean (P = 0.049), 25th (P = 0.015), and 50th (P = 0.026) percentiles and skewness (P = 0.004) than did the PMBC-B group. The 25th percentile of the ADC cutoff value (1.476 × 10-3 mm2 /s) demonstrated the best AUC (0.837) among the ADC values for distinguishing PMBC-A and PMBC-B. CONCLUSION: Whole-lesion ADC histogram analysis enables comprehensive evaluation of an MBC in its entirety and differentiating subtypes of MBC. Thus, it may be a helpful and supportive tool for conventional MRI. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:391-400.


Asunto(s)
Adenocarcinoma Mucinoso/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Adenocarcinoma Mucinoso/patología , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/patología , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
15.
Eur Spine J ; 26(10): 2512-2519, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-26874953

RESUMEN

PURPOSE: Using MR imaging, nerve root sedimentation sign (SedSign) was demonstrated to have a high sensitivity and specificity for diagnosis of symptomatic lumbar spinal stenosis (LSS) in selected patients. This study was to evaluate the diagnostic value of SedSign in differential diagnosis of LSS and non-specific low back pain (LBP) in consecutive patients. METHODS: A series of consecutive patients with lumbar spinal MRI examination for back/leg pain in orthopeadic clinic were included. These patients were followed up and divided into two groups, symptomatic LSS and non-specific LBP, according to symptoms and radiological findings. Using MR images, SedSign was assessed by two spine surgeons and one radiologist independently. Then sensitivity and specificity of SedSign was calculated. RESULT: A total of 320 patients (105 LSS and 215 non-specific LBP) were included. The SedSign had a sensitivity of 77.1 % and specificity of 47.0 % in the whole cohort. When these patients were stratified by dural sac cross-sectional areas (CSA), the SedSign had a sensitivity of 95.0 % and specificity of 4.7 % in patients with CSA ≤ 80 mm2 (severe radiologic stenosis), sensitivity of 74.2 % and specificity of 22.6 % in patients with CSA 80-100 mm2 (moderate radiologic stenosis), and sensitivity of 58.8 % and specificity of 61.0 % in patients with CSA 100-120 mm2 (mild radiologic stenosis). In selected cases composed by LSS patients with CSA ≤ 80 mm2 and non-specific LBP patients with CSA > 120 mm2, however, the SedSign had a sensitivity of 95.0 % and specificity of 80.0 %. CONCLUSION: The present data demonstrated that the SedSign was not able to discriminate symptomatic LSS from non-specific LBP after adjusting by dural sac CSA. The diagnostic value of the SedSign was still uncertain.


Asunto(s)
Vértebras Lumbares/diagnóstico por imagen , Estenosis Espinal/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Imagen por Resonancia Magnética , Estudios Retrospectivos , Sensibilidad y Especificidad
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3176-81, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26978931

RESUMEN

Heavy metal mining activities have caused the complex influence on the ecological environment of the mining regions. For example, a large amount of acidic waste water containing heavy metal ions have be produced in the process of copper mining which can bring serious pollution to the ecological environment of the region. In the previous research work, bare soil is mainly taken as the research target when monitoring environmental pollution, and thus the effects of land surface vegetation have been ignored. It is well known that vegetation condition is one of the most important indictors to reflect the ecological change in a certain region and there is a significant linkage between the vegetation spectral characteristics and the heavy metal when the vegetation is effected by the heavy metal pollution. It means the vegetation is sensitive to heavy metal pollution by their physiological behaviors in response to the physiological ecology change of their growing environment. The conventional methods, which often rely on large amounts of field survey data and laboratorial chemical analysis, are time consuming and costing a lot of material resources. The spectrum analysis method using remote sensing technology can acquire the information of the heavy mental content in the vegetation without touching it. However, the retrieval of that information from the hyperspectral data is not an easy job due to the difficulty in figuring out the specific band, which is sensitive to the specific heavy metal, from a huge number of hyperspectral bands. Thus the selection of the sensitive band is the key of the spectrum analysis method. This paper proposed a statistical analysis method to find the feature band sensitive to heavy metal ion from the hyperspectral data and to then retrieve the metal content using the field survey data and the hyperspectral images from China Environment Satellite HJ-1. This method selected copper ion content in the leaves as the indicator of copper pollution level, using stepwise multiple linear regression and cross validation on the dataset which is consisting of 44 groups of copper ion content information in the polluted vegetation leaves from Dexing Copper Mine in Jiangxi Province to build up a statistical model by also incorporating the HJ-1 satellite images. This model was then used to estimate the copper content distribution over the whole research area at Dexing Copper Mine. The result has shown that there is strong statistical significance of the model which revealed the most sensitive waveband to copper ion is located at 516 nm. The distribution map illustrated that the copper ion content is generally in the range of 0-130 mg · kg⁻¹ in the vegetation covering area at Dexing Copper Mine and the most seriously polluted area is located at the South-east corner of Dexing City as well as the mining spots with a higher value between 80 and 100 mg · kg⁻¹. This result is consistent with the ground observation experiment data. The distribution map can certainly provide some important basic data on the copper pollution monitoring and treatment.

17.
Sensors (Basel) ; 14(5): 9271-89, 2014 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-24859029

RESUMEN

The canopy foliage clumping effect is primarily caused by the non-random distribution of canopy foliage. Currently, measurements of clumping index (CI) by handheld instruments is typically time- and labor-intensive. We propose a low-cost and low-power automatic measurement system called Multi-point Linear Array of Optical Sensors (MLAOS), which consists of three above-canopy and nine below-canopy optical sensors that capture plant transmittance at different times of the day. Data communication between the MLAOS node is facilitated by using a ZigBee network, and the data are transmitted from the field MLAOS to a remote data server using the Internet. The choice of the electronic element and design of the MLAOS software is aimed at reducing costs and power consumption. A power consumption test showed that, when a 4000 mAH Li-ion battery is used, a maximum of 8-10 months of work can be achieved. A field experiment on a coniferous forest revealed that the CI of MLAOS may reveal a clumping effect that occurs within the canopy. In further work, measurement of the multi-scale clumping effect can be achieved by utilizing a greater number of MLAOS devices to capture the heterogeneity of the plant canopy.


Asunto(s)
Agricultura/instrumentación , Monitoreo del Ambiente/instrumentación , Bosques , Dispositivos Ópticos , Fotometría/instrumentación , Tracheophyta/crecimiento & desarrollo , Transductores , Diseño de Equipo , Análisis de Falla de Equipo
18.
Clin Imaging ; 109: 110115, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547669

RESUMEN

OBJECTIVES: The risk factors for lung cancer screening eligibility, age as well as smoking history, are also present for osteoporosis. This study aims to develop a visual scoring system to identify osteoporosis that can be applied to low-dose CT scans obtained for lung cancer screening. MATERIALS AND METHODS: We retrospectively reviewed 1000 prospectively enrolled participants in the lung cancer screening program at the Mount Sinai Hospital. Optimal window width and level settings for the visual assessment were chosen based on a previously described approach. Visual scoring of osteoporosis and automated measurement using dedicated software were compared. Inter-reader agreement was conducted using six readers with different levels of experience who independently visually assessed 30 CT scans. RESULTS: Based on previously validated formulas for choosing window and level settings, we chose osteoporosis settings of Width = 230 and Level = 80. Of the 1000 participants, automated measurement was successfully performed on 774 (77.4 %). Among these, 138 (17.8 %) had osteoporosis. There was a significant correlation between the automated measurement and the visual score categories for osteoporosis (Kendall's Tau = -0.64, p < 0.0001; Spearman's rho = -0.77, p < 0.0001). We also found substantial to excellent inter-reader agreement on the osteoporosis classification among the 6 radiologists (Fleiss κ = 0.91). CONCLUSIONS: Our study shows that a simple approach of applying specific window width and level settings to already reconstructed sagittal images obtained in the context of low-dose CT screening for lung cancer is highly feasible and useful in identifying osteoporosis.


Asunto(s)
Neoplasias Pulmonares , Osteoporosis , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/epidemiología , Detección Precoz del Cáncer , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Osteoporosis/diagnóstico por imagen
19.
ACS Nano ; 18(1): 581-591, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38126349

RESUMEN

Neural networks based on low-power artificial synapses can significantly reduce energy consumption, which is of great importance in today's era of artificial intelligence. Two-dimensional (2D) material-based floating-gate transistors (FGTs) have emerged as compelling candidates for simulating artificial synapses owing to their multilevel and nonvolatile data storage capabilities. However, the low erasing/programming speed of FGTs renders them unsuitable for low-energy-consumption artificial synapses, thereby limiting their potential in high-energy-efficient neuromorphic computing. Here, we introduce a FGT-inspired MoS2/Trap/PZT heterostructure-based polarized tunneling transistor (PTT) with a simple fabrication process and significantly enhanced erasing/programming speed. Distinct from the FGT, the PTT lacks a tunnel layer, leading to a marked improvement in its erasing/programming speed. The PTT's highest erasing/programming (operation) speed can reach ∼20 ns, which outperforms the performance of most FGTs based on 2D heterostructures. Furthermore, the PTT has been utilized as an artificial synapse, and its weight-update energy consumption can be as low as 0.0002 femtojoule (fJ), which benefits from the PTT's ultrahigh operation speed. Additionally, PTT-based artificial synapses have been employed in constructing artificial neural network simulations, achieving facial-recognition accuracy (95%). This groundbreaking work makes it possible for fabricating future high-energy-efficient neuromorphic transistors utilizing 2D materials.

20.
Medicine (Baltimore) ; 102(43): e34861, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37904473

RESUMEN

Gastric cancer (GC) is a significant contributor to cancer-related mortality globally, with the heterogeneity of metastasis and treatment impacting patient prognosis. Currently, the treatment of GC still relies on early surgical resection, and comprehensive treatment is needed for patients with metastatic GC. Anikis-related genes (ANRGs) have been shown to affect tumor metastasis. Exploring the role of ANRGs in GC will help us understand the mechanism of tumor metastasis; screening precise targets and selecting appropriate chemotherapeutics will help individualize the treatment of GC patients. In this study, we established a prognostic scoring model based on ANRGs and explored their association with GC patient prognosis, immune microenvironment, chemotherapeutic drug sensitivity, and small molecule compounds. Our findings revealed that a gene signature composed of ANXA5, CCN1, EGF, VTN, and ZBTB7A accurately predicted GC patient prognosis. Patients in the low-risk group had better outcomes, higher macrophage M1 infiltration, and higher tumor mutation burden. The half maximal inhibitory concentration (IC50) values of Ponatinib (ap.24534), Motesanib (amg.706), and Navitoclax (abt.263) were lower in the high-risk group, indicating that patients in the high-risk group were more sensitive to these chemotherapy drugs, meaning with better clinical outcomes. In addition, we screened the small molecule compound SGC-CBP30 that can inhibit ANXA5 and CCN1, and these results help individualized treatment of GC patients. Our study identified key genes based on ANRGs and developed a novel gene signature for predicting the prognosis of GC patients and understanding the relationship between immunity and tumor mutation burden. Additionally, we identified chemotherapeutic drugs that can guide GC treatment and elucidated the binding affinity between specific targeted drugs and distinct protein sites, providing novel insights for the precise treatment of GC patients.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Línea Celular Tumoral , Proteínas de Unión al ADN , Factores de Transcripción , Anexina A5 , Pronóstico , Microambiente Tumoral
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