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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Rapid Laser Processing of Thin Sr-Doped LaCrO 3– δ Interconnects for Solid Oxide Fuel Cells
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One-Pot Hydrothermal Synthesis of Elements (B, N, P)-Doped Fluorescent Carbon Dots for Cell Labelling, Differentiation and Outgrowth of Neuronal Cells
The use of the chemically modified one-step facile hydrothermal process to develop Boron (B), Nitrogen (N), and Phosphorous (P) doped carbon dots (E@CDs) is reported on in this work. The chemical characterization of the E@CDs was systematically studied by several analytical techniques that confer doping of elements by known characteristics. The obtained E@CDs had observed very homogeneous size distribution and displayed excitation dependent fluorescence properties, and high quantum yield (QY) was measured in case of B and N doping. Excellent cell viability and good cellular uptake was observed for all E@CDs. Lastly, E@CDs were compared with pristine CDs on their effect on cell labelling, neural differentiation process and outgrowth of neurite network. By manipulating the doping of CDs, we can control the branching pattern and outgrowth of neuronal developments. The E@CDs are capable due to their photostability biocompatibility, and possible selective affinity towards nanomedicine applications.
Association of qualitative and quantitative imaging features on multiphasic multidetector CT with tumor grade in clear cell renal cell carcinoma
Purpose: The purpose of the study was to determine if enhancement features and qualitative imaging features on multiphasic multidetector computed tomography (MDCT) were associated with tumor grade in patients with clear cell renal cell carcinoma (ccRCC). Methods: In this retrospective, IRB approved, HIPAA-compliant, institutional review board-approved study with waiver of informed consent, 127 consecutive patients with 89 low grade (LG) and 43 high grade (HG) ccRCCs underwent preoperative four-phase MDCT in unenhanced (UN), corticomedullary (CM), nephrographic (NP), and excretory (EX) phases. Previously published quantitative (absolute peak lesion enhancement, absolute peak lesion enhancement relative to normal enhancing renal cortex, 3D whole lesion enhancement and the wash-in/wash-out of enhancement within the 3D whole lesion ROI) and qualitative (enhancement pattern; presence of necrosis; pattern of; tumor margin; tumor–parenchymal interface, tumor–parenchymal interaction; intratumoral vascularity; collecting system infiltration; renal vein invasion; and calcification) assessments were obtained for each lesion independently by two fellowship-trained genitourinary radiologists. Comparisons between variables included χ{sup 2}, ANOVA, and student t test. p values less than 0.05 were considered to be significant. Inter-reader agreement was obtained with the Gwet agreement coefficient (AC1) and standard error (SE) was reported. Results: No significant differences were observed between the LG and HG ccRCC cohorts with respect to absolute peak lesion enhancement and relative lesion enhancement ratio. There was a significant inverse correlation between low and high grade ccRCC and tumor enhancement the NP (71 HU vs. 54 HU, p < 0.001) and EX (52 HU vs. 39 HU, p < 0.001) phases using the 3D whole lesion ROI method. The percent wash-in of 3D enhancement from the UN to the CM phase was also significantly different between LG and HG ccRCCs (352% vs. 255%, p = 0.003). HG lesions showed significantly more calcification, necrosis, collecting system infiltration and ill-defined tumor margins (p < 0.05). Overall agreement between the two readers had a mean AC1 of 0.8172 (SE 0.0235). Conclusions: Quantitatively, high grade ccRCC had significantly lower whole lesion enhancement in the NP and EX phases on MDCT. Qualitatively, high grade ccRCC were significantly more likely to be associated with calcifications, necrosis, collecting system infiltration, and an ill-defined tumor margin.
Juxtatumoral perinephric fat analysis in clear cell renal cell carcinoma
Purpose: The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1–2) versus high-grade (ISUP 3–4) clear cell renal cell carcinoma (ccRCC). Methods: In this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively. Results: All methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75. Conclusions: Our study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.
CT-based machine learning model to predict the Fuhrman nuclear grade of clear cell renal cell carcinoma
Purpose: To predict the Fuhrman grade of clear cell renal cell carcinoma (ccRCC) with a machine learning classifier based on single- or three-phase computed tomography (CT) images. Materials and methods: Patients with pathologically proven ccRCC from February 1, 2009 to September 31, 2018 who were not treated were retrospectively collected for machine learning-based analysis. The texture features were extracted and ranked from precontrast phase (PCP), corticomedullary phase (CMP), nephrographic phase (NP) and three-phase CT images, and open-source gradient boosting from the decision tree library of CatBoost was used to establish a machine learning classifier to differentiate low- from high-grade ccRCC. The performances of machine learning classifiers based on features from single- and three-phase CT images were compared with each other. Results: A total of 231 patients with 232 pathologically proven ccRCC lesions were retrospectively collected. 35, 36, 41, and 22 Features were extracted and ranked from PCP, CMP, NP, and three-phase CT images, respectively. The machine learning model based on three-phase CT images [area under the ROC curve (AUC) = 0.87] achieved the best diagnostic performance for differentiating low- from high-grade ccRCC, followed by single-phase NP (AUC = 0.84), CMP (AUC = 0.80), and PCP images (AUC = 0.82). Conclusion: Machine learning classifiers can be promising noninvasive techniques to differentiate low- and high-Fuhrman nuclear grade ccRCC, and classifiers based on three-phase CT images are superior to those based on features from each single phase.
Metastatic castration resistant prostate cancer with squamous cell, small cell, and sarcomatoid elements—a clinicopathologic and genomic sequencing-based discussion
Histologic variants are uncommon but well reported amongst cases of prostatic adenocarcinoma, including those in the setting of hormonal and/or chemoradiation therapy and castration resistance. However, the spectrum of morphologic phenotypes and molecular alterations present in such histologic variants are still incompletely understood. Herein, we describe a case of metastatic prostatic adenocarcinoma with hormonal and chemoradiation therapy-associated differentiation, displaying a combination of squamous cell, small cell, and sarcomatoid elements. The morphologic, immunohistochemical, and molecular observations are discussed with attention given to the gene alterations present, including in TP53, NF1, AR, PTEN, and RB1. Finally, we will compare our findings with those observed in uncommonly reported similar cases so as to detail the molecular underpinnings of such processes which may carry therapeutic implications.
Overexpression of low density lipoprotein receptor-related protein 1 (LRP1) is associated with worsened prognosis and decreased cancer immunity in clear-cell renal cell carcinoma
Clear-cell renal cell carcinoma (ccRCC) is characterized with underlying genetic disorders and the role of low density lipoprotein receptor-related protein 1 (LRP1) in ccRCC is unknown.
Electrochemical performance and stability of the cathode for solid oxide fuel cells. V. high performance and stable Pr 2 NiO 4 as the cathode for solid oxide fuel cells
The polarization loss due to oxygen reduction at the cathode in solid oxide fuel cells is a thermally activated process; therefore, as temperature is lowered, the loss becomes substantial. Highly active cathodes have been investigated by several groups; equally important, if not more, is the stability of these electrodes. The high performance and stable Pr 2 NiO 4 cathode was studied by impedance spectroscopy and dc current–potential sweeping methods. The power density in Pr 2 NiO 4 -based anode supported button cells was in the range between 0.65 and 0.7 W/cm 2 at 750 degrees C at the external load of 0.8 V. The degradation rate at 0.8 V was approximately 3% per 1000 h up to 2000 h. The electrode resistance is a function of external loads, thus also varies with current densities. The relationship between electrode resistance and external loads is non-linear, which may changes in lattice oxygen nonstoichiometry of the cathodes.
Electrode optimization for efficient hydrogen production using an SO2-depolarized electrolysis cell
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Single High-Dose Radiation Enhances Dendritic Cell Homing and T Cell Priming by Promoting Reactive Oxygen Species-Induced Cytoskeletal Reorganization
Radiation therapy (RT) affects tumor-infiltrating immune cells, cooperatively driving tumor growth inhibition. However, there is still no absolute consensus on whether the homing ability of dendritic cells (DCs) is affected by direct x-ray irradiation. Most importantly, the underlying mechanisms are poorly understood.
Fractionated Radiation Severely Reduces the Number of CD8+ T Cells and Mature Antigen Presenting Cells Within Lung Tumors
The combination of standard-of-care radiation therapy (RT) with immunotherapy is moving to the mainstream of non-small cell lung cancer treatment. Multiple preclinical studies reported on the CD8{sup +} T cell stimulating properties of RT, resulting in abscopal therapeutic effects. A literature search demonstrates that most preclinical lung cancer studies applied subcutaneous lung tumor models. Hence, in-depth immunologic evaluation of clinically relevant RT in orthotopic lung cancer models is lacking.
The Plasma Simulation Code: A modern particle-in-cell code with patch-based load-balancing
This work describes the Plasma Simulation Code (psc), an explicit, electromagnetic particle-in-cell code with support for different order particle shape functions. We review the basic components of the particle-in-cell method as well as the computational architecture of the psc code that allows support for modular algorithms and data structure in the code. We then describe and analyze in detail a distinguishing feature of psc: patch-based load balancing using space-filling curves which is shown to lead to major efficiency gains over unbalanced methods and a previously used simpler balancing method.
Rechargeability and economic aspects of alkaline zinc-manganese dioxide cells for electrical storage and load leveling
Batteries based on manganese dioxide (MnO2) cathodes are good candidates for grid-scale electrical energy storage, as MnO2 is low-cost, relatively energy dense, safe, water-compatible, and non-toxic. Alkaline Zn-MnO2 cells, if cycled at reduced depth of discharge (DOD), have been found to achieve substantial cycle life with battery costs projected to be in the range of $100 to 150 per kWh (delivered). Commercialization of rechargeable Zn-MnO2 batteries has in the past been hampered due to poor cycle life. In view of this, the work reported here focuses on the long-term rechargeability of prismatic MnO2 cathodes at reduced DOD when exposed to the effects of Zn anodes and with no additives or specialty materials. Over 3000 cycles is shown to be obtainable at 10% DOD with energy efficiency >80%. The causes of capacity fade during long-term cycling are also investigated and appear to be mainly due to the formation of irreversible manganese oxides in the cathode. Analysis of the data indicates that capacity loss is rapid in the first 250 cycles, followed by a regime of stability that can last for thousands of cycles. A model has been developed that captures the behavior of the cells investigated using measured state of charge (SOC) data as input. An approximate economic analysis is also presented to evaluate the economic viability of Zn-MnO2 batteries based on the experiments reported here. (C) 2014 Elsevier B.V. All rights reserved.
Lithium-ion battery cell-level control using constrained model predictive control and equivalent circuit models
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Enhanced Performance of Li|LiFePO4 Cells Using CsPF6 as an Electrolyte Additive
The practical application of lithium (Li) metal anode in rechargeable Li batteries is hindered by both the growth of Li dendrites and the low Coulombic efficiency (CE) during repeated charge/discharge cycles. Recently, we have discovered that CsPF6 as an electrolyte additive can significantly suppress Li dendrite growth and lead to highly compacted and well aligned Li nanorod structure during Li deposition on copper substrates. In this paper, the effect of CsPF6 additive on the performance of rechargeable Li metal batteries with lithium iron phosphate (LFP) cathode was further studied. Li|LFP coin cells with CsPF6 additive in electrolytes show well protected Li anode surface, decreased resistance, enhanced rate capability and extended cycling stability. In Li|LFP cells, the electrolyte with CsPF6 additive shows excellent long-term cycling stability (at least 500 cycles) at a charge current density of 0.5 mA cm-2 without internal short circuit. At high charge current densities, the effect of CsPF6 additive becomes less significant. Future work needs to be done to protect Li metal anode, especially at high charge current densities and for long cycle life.