Search results for "Bust"
showing 10 items of 1000 documents
Preservation of genetic and regulatory robustness in ancient gene duplicates of Saccharomyces cerevisiae
2014
[EN] Biological systems remain robust against certain genetic and environmental challenges. Robustness allows the exploration of ecological adaptations. It is unclear what factors contribute to increasing robustness. Gene duplication has been considered to increase genetic robustness through functional redundancy, accelerating the evolution of novel functions. However, recent findings have questioned the link between duplication and robustness. In particular, it remains elusive whether ancient duplicates still bear potential for innovation through preserved redundancy and robustness. Here we have investigated this question by evolving the yeast Saccharomyces cerevisiae for 2200 generations …
Regression diagnostics applied in kinetic data processing: Outlier recognition and robust weighting procedures
2010
An efficient protocol, based on advanced statistical diagnostics and robust fitting techniques applied to the least-squares processing of kinetic data of chemical reactions, is presented and discussed. The procedure, which is aimed at obtaining highly accurate estimation of the fitting parameters, consists of the identification of the outliers that remarkably impair the fitting by means of the so-called “leverage analysis” and some related diagnostics. This approach allows the elimination of the actually aberrant observations from the data set and/or their robust weighting to inhibit the negative effects induced on the data fitting, with consequent reduction of the bias introduced into the …
<title>Methodology for quantitative analysis of scaling effects in multiresolution datasets acquired with airborne sensors flying at different …
2001
Scaling issues are always playing a critical role in most studies based on remote sensing data. The process of getting quantitative scaling information from raw multi-resolution images is not trivial, and many aspects must be taken very carefully into consideration. To get a better picture about the role of spatial resolution, we conducted a series of flights in summer 1997, in several test sites over Spain and Portugal. In order to minimize the time of acquisition (to get minimal changes in atmospheric status and solar illumination) we used three flight altitude levels, that produced images with 1.25 m, 3 m and 12 m resolutions. The main steps in our methodology are: a) Geometrical registr…
Determination of n-alkanes, polycyclic aromatic hydrocarbons and hopanes in atmospheric aerosol: evaluation and comparison of thermal desorption GC-M…
2019
Organic aerosol (OA) constitutes a large fraction of fine particulate matter (PM) in the urban air. However, the chemical nature and sources of OA are not well constrained. Quantitative analysis of OA is essential for understanding the sources and atmospheric evolution of fine PM, which requires accurate quantification of some organic compounds (e.g., markers). In this study, two analytical approaches, i.e., thermal desorption (TD) gas chromatography mass spectrometry (GC-MS) and solvent extract (SE) GC-MS, were evaluated for the determination of n-alkanes, polycyclic aromatic hydrocarbons (PAHs) and hopanes in ambient aerosol. For the SE approach, the recovery obtained is 89.3 %–101…
Determination of n-alkanes, PAHs and hopanes in atmospheric aerosol: evaluation and comparison of thermal desorption GC-MS and solvent extraction GC-…
2019
Organic aerosol (OA) constitutes a large fraction of fine particulate matter (PM) in the urban air. However, the chemical nature and sources of OA are not well constrained. Quantitative analysis of OA is essential for understanding the sources and atmospheric evolution of fine PM, which requires accurate quantification of some organic compounds (e.g., markers). In this study, two analytical approaches, i.e., thermal desorption (TD) gas chromatography-mass spectrometry (GC-MS) and solvent extract (SE) GC-MS were evaluated for the determination of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and hopanes in ambient aerosol. For the SE approach, the recovery obtained is 89.3–101.5&…
Determination of NH(3) in pyrolysis gases by ammonia selective electrode.
1993
The suitability of ion-selective electrode for the determination of ammonia in pyrolysis gases of fossil fuels was studied. The ammonia was absorbed into acidic solution and two kinds of determination methods were carried out. The ammonia was either measured directly from the acid solution, or ammonia was first released into the gas phase and then determined (air gap method) by the ammonia selective electrode. The electrode functioned well in both cases, but the linear calibration range was rather narrow, slightly more than one tenfold. The quantitative detection limit in the water phase was 5 × 10−6M (0.085 ppm) NH3 and in gas phase operation solutions above 5 × 10−4M (8.5 ppm) NH3 it was …
Combining Haar Wavelet and Karhunen Loeve Transforms for Medical Images Watermarking
2014
This paper presents a novel watermarking method, applied to the medical imaging domain, used to embed the patient’s data into the corresponding image or set of images used for the diagnosis. The main objective behind the proposed technique is to perform the watermarking of the medical images in such a way that the three main attributes of the hidden information (i.e., imperceptibility, robustness, and integration rate) can be jointly ameliorated as much as possible. These attributes determine the effectiveness of the watermark, resistance to external attacks, and increase the integration rate. In order to improve the robustness, a combination of the characteristics of Discrete Wavelet and K…
Fast nosological imaging using canonical correlation analysis of brain data obtained by two-dimensional turbo spectroscopic imaging.
2007
A new fast and accurate tissue typing technique has recently been successfully applied to prostate MR spectroscopic imaging (MRSI) data. This technique is based on canonical correlation analysis (CCA), a statistical method able to simultaneously exploit the spectral and spatial information characterizing the MRSI data. Here, the performance of CCA is further investigated by using brain data obtained by two-dimensional turbo spectroscopic imaging (2DTSI) from patients affected by glioblastoma. The purpose of this study is to investigate the applicability of CCA when typing tissues of heterogeneous tumors. The performance of CCA is also compared with that of ordinary correlation analysis on s…
Transition Metal Compound Oxide Catalysts for Lowering the Light Off-Temperature of Particles from Diesel Exhaust
1993
Publisher Summary It has been realized that particle emissions from diesel engines are a severe environmental problem, which is difficult to solve by engine modifications alone. Even if the combustion occurs in a high excess of air, appreciable amounts of soot particles are found. Cracking processes, dehydrogenation, and polymerization play an important role in the formation of soot. To reduce soot fraction, several methods have been developed in the past, but most of them have fundamental disadvantages. Thus, a new procedure based on the catalytic burning of the soot in the exhaust gas is becoming important. This chapter describes the effect of several compound oxides. Further investigatio…
Shear capacity in concrete beams reinforced by stirrups with two different inclinations
2014
Abstract A model for the estimation of shear capacity in Reinforced Concrete (RC) beams with web reinforcement is provided by introducing a generalization of classical plastic Nielsen’s model, which is based on the variable-inclination stress-field approach. The proposed model is able to predict the shear capacity in RC beams reinforced by means of stirrups having two different inclinations and longitudinal web bars. A numerical comparison with the results of experimental tests and those provided by a Finite Element Model (FEM) based on the well known theory of Modified Compression Field Theory (MCFT) is carried out for validating the robustness of the proposed model. Finally, a set of para…