Purpose: Technetium-99m ((99m)Tc) has been widely used as an imaging agent but only recently has been considered for therapeutic applications. This study aims to analyze the potential use of (99m)Tc Auger electrons fo...
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Purpose: Technetium-99m ((99m)Tc) has been widely used as an imaging agent but only recently has been considered for therapeutic applications. This study aims to analyze the potential use of (99m)Tc Auger electrons for targeted tumor radiotherapy by evaluating the DNA damage and its probability of correct repair and by studying the cellular kinetics, following (99m)Tc Auger electron irradiation in comparison to iodine-131 ((131)I) beta minus particles and astatine-211 ((211)At) alpha particle irradiation. methods: computational models were used to estimate the yield of DNA damage (fast Monte Carlo damage algorithm), the probability of correct repair (Monte Carlo excision repair algorithm), and cell kinetic effects (virtual cell radiobiology algorithm) after irradiation with the selected particles. Results: The results obtained with the algorithms used suggested that (99m)Tc CKMMX (all M-shell Coster-Kroning-CK- and super-CK transitions) electrons and Auger MXY (all M-shell Auger transitions) have a therapeutic potential comparable to high linear energy transfer (211)At alpha particles and higher than (131)I beta minus particles. All the other (99m)Tc electrons had a therapeutic potential similar to (131)I beta minus particles. Conclusions: (99m)Tc CKMMX electrons and Auger MXY presented a higher probability to induce apoptosis than (131)I beta minus particles and a probability similar to (211)At alpha particles. Based on the results here, (99m)Tc CKMMX electrons and Auger MXY are useful electrons for targeted tumor radiotherapy. (c) 2010 American Association of Physicists in Medicine. [DOI: 10.1118/1.3451117]
This study takes place in the frame of a research project to better understand the flow that develops in multistage high-speed compressors. First, the paper presents the high-speed 3.5-stage compressor CREATE and the ...
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This study takes place in the frame of a research project to better understand the flow that develops in multistage high-speed compressors. First, the paper presents the high-speed 3.5-stage compressor CREATE and the methods that are considered to increase the data reliability and the investigation capability with such realistic compressors. Second, flow simulations, achieved with three-dimensional unsteady Reynolds-averaged Navier-Stokes computations over the whole compressor spatial and temporal periodicities, are analyzed through a study of their sensitivity to some parameters such as the inlet conditions, the space and time discretization, and technological effects such as tip and hub clearances. Finally the paper focuses on the methodology used to compare the experimental and numerical results over the whole compressor periodicities. The local spatial and temporal flow structures are well estimated. The key is the advection of these structures, which interact with each other and produce a significant part of the flow fluctuations in-the downstream stages. The paper presents the zone close to the casing, where losses and blockage are induced by the interaction between the tip leakage flow and the incoming wakes. This is where the numerical simulation has to be improved, in order to accurately predict the performance.
MicroRNAs (miRNAs) are an important class of non-coding RNAs that play an essential role in the occurrence and development of various diseases. Identifying the potential miRNA-disease associations (MDAs) can be benefi...
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MicroRNAs (miRNAs) are an important class of non-coding RNAs that play an essential role in the occurrence and development of various diseases. Identifying the potential miRNA-disease associations (MDAs) can be beneficial in understanding disease pathogenesis. Traditional laboratory experiments are expensive and time-consuming. computational models have enabled systematic large-scale prediction of potential MDAs, greatly improving the research efficiency. With recent advances in deep learning, it has become an attractive and powerful technique for uncovering novel MDAs. Consequently, numerous MDA prediction methods based on deep learning have emerged. In this review, we first summarize publicly available databases related to miRNAs and diseases for MDA prediction. Next, we outline commonly used miRNA and disease similarity calculation and integration methods. Then, we comprehensively review the 48 existing deep learning-based MDA computation methods, categorizing them into classical deep learning and graph neural network-based techniques. Subsequently, we investigate the evaluation methods and metrics that are frequently used to assess MDA prediction performance. Finally, we discuss the performance trends of different computational methods, point out some problems in current research, and propose 9 potential future research directions. Data resources and recent advances in MDA prediction methods are summarized in the GitHub repository https://***/sheng-n/DL-miRNA-disease-association-methods.
The result of the work is obtaining difference schemes for dynamic systems, which are described by systems of ordinary differential equations of the second order based on the classical methods of Bossak, Newmark and t...
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The lipophilicity of new two series of anticancer active 10-substituted 1,6- and 3,6-diazaphenothiazines has been investigated using reversed-phase thin-layer chromatography. Their lipophilicity (R-M0 and log P-TLC) w...
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The lipophilicity of new two series of anticancer active 10-substituted 1,6- and 3,6-diazaphenothiazines has been investigated using reversed-phase thin-layer chromatography. Their lipophilicity (R-M0 and log P-TLC) was determined with mixtures of acetone and Tris buffer as mobile phases. The relative lipophilicity parameter R-M0 and specific hydrophobic surface area b were significantly intercorrelated showing congeneric classes of diazaphenothiazines. The parameter R-M0 was transformed into parameter log P-TLC by use of the calibration curve. The parameter log P-TLC was compared with computationally calculated lipophilic parameters log P-calcd. The lipophilicity was discussed with the structure elements and was correlated with molecular descriptors, ADME properties and in vitro anticancer activities.
A variety of computational methods, including the semiempirical techniques AM1, PM3, and MNDO, and the thermochemical basis sets of Benson and Stine, was used to calculate and compare heats of formation (DELTAH(f)-deg...
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A variety of computational methods, including the semiempirical techniques AM1, PM3, and MNDO, and the thermochemical basis sets of Benson and Stine, was used to calculate and compare heats of formation (DELTAH(f)-degrees) data for optimized geometries of a variety of aromatic and nonaromatic heterocycles. Detailed analyses, including 6-31G* and MP2/6-31G* ab initio calculations, were performed for the oxazole and thiazole heterocycles. The results indicate a scatter among the methods sensitive to the nature of the heterocycle. This was in particular evident in the oxazole molecule, where AM1 gave a singularly high value of DELTAH(f)-degrees consistent with longer calculated bond lengths, particularly about the oxygen atom. Aromatic stabilization energy appears to be addressed differently among the employed methods. Implications of this contrast applied to calculation of macromolecular systems containing heterocyclic units are discussed.
This article provides a short summary of the theoretical approaches to understanding gas-phase reactions. In particular, the quantum-chemical bond-additivity correction (BAC) method for predicting molecular thermochem...
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This article provides a short summary of the theoretical approaches to understanding gas-phase reactions. In particular, the quantum-chemical bond-additivity correction (BAC) method for predicting molecular thermochemistry of gas-phase molecules is described. A brief discussion of the use of RRKM methods for predicting the rates of unimolecular reactions and of ab initio methods for predicting the rates of bimolecular reactions is also presented. Finally, the question of when gas-phase reactions are likely to be important in CVD is discussed. Criteria are proposed for performing a first-order evaluation of the extent of precursor pyrolysis in the CVD of hard coatings. Examples from the CVD of titanium-containing species, boron nitride, and silicon carbide will be used for illustration. (C) 1998 Elsevier Science S.A. All rights reserved.
Implantable medical devices that can facilitate therapy transport to localized sites are being developed for a number of diverse applications, including the treatment of diseases such as diabetes and cancer, and tissu...
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Implantable medical devices that can facilitate therapy transport to localized sites are being developed for a number of diverse applications, including the treatment of diseases such as diabetes and cancer, and tissue regeneration after myocardial infraction. These implants can take the form of an encapsulation device which encases therapy in the form of drugs, proteins, cells, and bioactive agents, in semi-permeable membranes. Such implants have shown some success but the nature of these devices pose a barrier to the diffusion of vital factors, which is further exacerbated upon implantation due to the foreign body response (FBR). The FBR results in the formation of a dense hypo-permeable fibrous capsule around devices and is a leading cause of failure in many implantable technologies. One potential method for overcoming this diffusion barrier and enhancing therapy transport from the device is to incorporate local fluid flow. In this work, we used experimentally informed inputs to characterize the change in the fibrous capsule over time and quantified how this impacts therapy release from a device using computational methods. Insulin was used as a representative therapy as encapsulation devices for Type 1 diabetes are among the most-well characterised. We then explored how local fluid flow may be used to counteract these diffusion barriers, as well as how a more practical pulsatile flow regimen could be implemented to achieve similar results to continuous fluid flow. The generated model is a versatile tool toward informing future device design through its ability to capture the expected decrease in insulin release over time resulting from the FBR and investigate potential methods to overcome these effects. An experimentally informed device model capturing reduced factor transport resulting from the fibrous capsule (FC) and recovered using fluid flow.
In the present study, aluminium hybrid surface composites were prepared by incorporating boron carbide (B4C) and Aluminium oxide (Al2O3) ceramic particles via the Friction Stir Processing (FSP) route. Tool rotational ...
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In the present study, aluminium hybrid surface composites were prepared by incorporating boron carbide (B4C) and Aluminium oxide (Al2O3) ceramic particles via the Friction Stir Processing (FSP) route. Tool rotational speed, Tool traverse speed, Axial force, and Reinforcement ratio were the chosen process parameters. Response Surface Method (RSM) based Central Composite Design (CCD) was used to conduct the experimental trials. A second-order regression equation was developed for the responses, ultimate tensile strength (UTS), and wear rate (WR). Statistical tests were performed to check the adequacy of the regression models. The effect of process parameters on the responses was studied. It was found that tool traverse speed was the most dominant process parameter, followed by tool rotational speed, axial force, and reinforcement ratio. The optimal process parameters for the responses were found using a genetic algorithm, where the regression equations from RSM were used as the objective function.
Experimental data on fully laminar and transitional shock-wave/boundary-layer interactions in two-dimensional compression corners are provided and used for the validation of two full Navier-Stokes solvers, as well as ...
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Experimental data on fully laminar and transitional shock-wave/boundary-layer interactions in two-dimensional compression corners are provided and used for the validation of two full Navier-Stokes solvers, as well as for checking the capabilities and limitations of simple analytical prediction methods. Viscous pressure interaction, free interaction, and inviscid oblique shock theory are found to predict well the pressure levels on the flat plate upstream of the interaction, within the separated region, and downstream of the interaction, respectively. The reference temperature theory is found to perform well in attached flow regimes both upstream and downstream of the interaction region and to provide the basis for a universal peak heating correlation law. Full Navier-Stokes computations are necessary, however, to predict the extent of the interaction region and the associated influence on the pressure distribution (control effectiveness) as web as the detailed heat transfer distribution. To achieve this, very fine gridding coupled with the use of strict convergence criteria (based on the evolution of the location of the separation point rather than on standard density residuals) is shown to be necessary. It is finally shown that, although sophisticated turbulence models need to be further developed before the detailed characteristics of fully turbulent shock-wave/boundary-layer interactions may be predicted, transitional interactions (where transition typically occurs in the neighborhood of reattachment) may be adequately handled by algebraic turbulence models ''switched on'' just downstream of reattachment.
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