Maximum Energy Subsampling: A General Scheme For Multi-resolution Image Representation And Analysis

Image descriptors play an important role in image representation and analysis. Multi-resolution image descriptors can effectively characterize complex images and extract their hidden information. Wavelets descriptors have been widely used in multi-resolution image analysis. However, making the wavelets transform shift and rotation invariant produces redundancy and requires complex matching processes. As to other multi-resolution descriptors, they usually depend on other theories or information, such as filtering function, prior-domain knowledge, etc.; that not only increases the computation complexity, but also generates errors. We propose a novel multi-resolution scheme that is capable of transforming any kind of image descriptor into its multi-resolution structure with high computation accuracy and efficiency. Our multi-resolution scheme is based on sub-sampling an image into an odd-even image tree. Through applying image descriptors to the odd-even image tree, we get the relative multi-resolution image descriptors. Multi-resolution analysis is based on downsampling expansion with maximum energy extraction followed by upsampling reconstruction. Since the maximum energy usually retained in the lowest frequency coefficients; we do maximum energy extraction through keeping the lowest coefficients from each resolution level. Our multi-resolution scheme can analyze images recursively and effectively without introducing artifacts or changes to the original images, produce multi-resolution representations, obtain higher resolution images only using information from lower resolutions, compress data, filter noise, extract effective image features and be implemented in parallel processing

On the investigation of alcohol synthesis via the Fischer Tropsch reaction

The Fischer Tropsch (FT) reaction is hydrogenation of carbon oxides (mainly carbon monoxide) to produce hydrocarbons and alcohols. The produced alcohols can be used as substitutes to motor fuel or as fuel additives to enhance the octane number. The use of alcohols significantly reduces the environment related pollution. This thesis was aimed to investigate the alcohol synthesis via the FT reaction. Cobalt molybdenum based catalyst and cobalt copper based mixed oxide catalyst are two patented catalyst systems for alcohol synthesis. This study investigated the preparation and evaluation of these two catalyst systems. The highest activity (30% CO conversion) and alcohol yield (methanol: 8% higher alcohols: 13%) was obtained with an operation condition of 580 K, 75 bar, GHSV = 1225 h-1 and syngas ratio of 2 for cobalt molybdenum based catalyst. Carbon monoxide hydrogenation to synthesize alcohol was also investigated over gold containing catalyst. When ZnO was used as a support, it was found that the addition of gold could shift the alcohol distribution towards higher alcohol side. The carbon monoxide and hydrogen used for the FT reaction is mainly generated by steam reforming reaction. This thesis investigated the possibility of combining the steam reforming reaction and the FT reaction together. Ruthenium supported catalysts were investigated for this purpose. The obtained results demonstrate that both steam reforming and the FT alcohol synthesis can be performed over the same catalyst in the same reactor.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Identification of candidate genes involved in wax deposition in Poa pratensis by RNA-seq

A, Randomness test of cDNA fragments; B, Sequencing saturation analysis. T1 and T2 represent NEZm; T3 and T4 represent EBZ. (PDF 290 kb

Dual Functions of Interferon Regulatory Factors 7C in Epstein-Barr Virus–Mediated Transformation of Human B Lymphocytes

Epstein-Barr virus (EBV) infection is associated with several human malignancies. Interferon (IFN) regulatory factor 7 (IRF-7) has several splicing variants, and at least the major splicing variant (IRF-7A) has oncogenic potential and is associated with EBV transformation processes. IRF-7C is an alternative splicing variant with only the DNA-binding domain of IRF-7. Whether IRF-7C is present under physiological conditions and its functions in viral transformation are unknown. In this report, we prove the existence of IRF-7C protein and RNA in certain cells under physiological conditions, and find that high levels of IRF-7C are associated with EBV transformation of human primary B cells in vitro as well as EBV type III latency. EBV latent membrane protein 1 (LMP-1) stimulates IRF-7C expression in B lymphocytes. IRF-7C has oncogenic potential in rodent cells and partially restores the growth properties of EBV-transformed cells under a growth-inhibition condition. A tumor array experiment has identified six primary tumor specimens with high levels of IRF-7C protein—all of them are lymphomas. Furthermore, we show that the expression of IRF-7C is apparently closely associated with other IRF-7 splicing variants. IRF- 7C inhibits the function of IRF-7 in transcriptional regulation of IFN genes. These data suggest that EBV may use splicing variants of IRF-7 for its transformation process in two strategies: to use oncogenic properties of various IRF-7 splicing variants, but use one of its splicing variants (IRF-7C) to block the IFN-induction function of IRF-7 that is detrimental for viral transformation. The work provides a novel relation of host/virus interactions, and has expanded our knowledge about IRFs in EBV transformation

On the investigation of alcohol synthesis via the Fischer Tropsch reaction

The Fischer Tropsch (FT) reaction is hydrogenation of carbon oxides (mainly carbon monoxide) to produce hydrocarbons and alcohols. The produced alcohols can be used as substitutes to motor fuel or as fuel additives to enhance the octane number. The use of alcohols significantly reduces the environment related pollution. This thesis was aimed to investigate the alcohol synthesis via the FT reaction. Cobalt molybdenum based catalyst and cobalt copper based mixed oxide catalyst are two patented catalyst systems for alcohol synthesis. This study investigated the preparation and evaluation of these two catalyst systems. The highest activity (30% CO conversion) and alcohol yield (methanol: 8% higher alcohols: 13%) was obtained with an operation condition of 580 K, 75 bar, GHSV = 1225 h-1 and syngas ratio of 2 for cobalt molybdenum based catalyst. Carbon monoxide hydrogenation to synthesize alcohol was also investigated over gold containing catalyst. When ZnO was used as a support, it was found that the addition of gold could shift the alcohol distribution towards higher alcohol side. The carbon monoxide and hydrogen used for the FT reaction is mainly generated by steam reforming reaction. This thesis investigated the possibility of combining the steam reforming reaction and the FT reaction together. Ruthenium supported catalysts were investigated for this purpose. The obtained results demonstrate that both steam reforming and the FT alcohol synthesis can be performed over the same catalyst in the same reactor

Modelling the Age-Hardening Precipitation by a Revised Langer and Schwartz Approach with Log-Normal Size Distribution

A new numerical modelling approach integrating the Langer and Schwartz approach and log-normal particle size distribution has been developed to depict the precipitation kinetics of age-hardening precipitates in Al alloys. The modelling framework has been implemented to predict the precipitation behavior of the key secondary phases in 6xxx and 7xxx Al alloys subjected to artificial aging. The simulation results are in good agreement with the available experimental data in terms of precipitate number density, radius, and volume fraction. The initial shape parameter of the log-normal size distribution entering the modeling framework turns to play an important role in affecting the later-stage evolution of precipitation. It is revealed that the evolution of size distribution is not significant when a small shape parameter is adopted in the modelling, while an initial large shape parameter will cause substantial broadening of the particle size distribution during aging. Regardless of the magnitude of shape parameter, a broadening of the particle size distribution as predicted by the present model is in agreement with experimental observations. It is also shown that large shape parameter will accelerate the coarsening rate at later aging stage, which induces fast decreasing of number density and increased growth rate of mean/critical radius. A comparison to the Euler-like multi-class approach demonstrates that the integration of more realistic log-normal distribution and Langer and Schwartz model make the present modelling faster and equivalently accurate in precipitation prediction.publishedVersio

Dual Functions of Interferon Regulatory Factors 7C in Epstein-Barr Virus–Mediated Transformation of Human B Lymphocytes

Epstein-Barr virus (EBV) infection is associated with several human malignancies. Interferon (IFN) regulatory factor 7 (IRF-7) has several splicing variants, and at least the major splicing variant (IRF-7A) has oncogenic potential and is associated with EBV transformation processes. IRF-7C is an alternative splicing variant with only the DNA-binding domain of IRF-7. Whether IRF-7C is present under physiological conditions and its functions in viral transformation are unknown. In this report, we prove the existence of IRF-7C protein and RNA in certain cells under physiological conditions, and find that high levels of IRF-7C are associated with EBV transformation of human primary B cells in vitro as well as EBV type III latency. EBV latent membrane protein 1 (LMP-1) stimulates IRF-7C expression in B lymphocytes. IRF-7C has oncogenic potential in rodent cells and partially restores the growth properties of EBV-transformed cells under a growth-inhibition condition. A tumor array experiment has identified six primary tumor specimens with high levels of IRF-7C protein—all of them are lymphomas. Furthermore, we show that the expression of IRF-7C is apparently closely associated with other IRF-7 splicing variants. IRF-7C inhibits the function of IRF-7 in transcriptional regulation of IFN genes. These data suggest that EBV may use splicing variants of IRF-7 for its transformation process in two strategies: to use oncogenic properties of various IRF-7 splicing variants, but use one of its splicing variants (IRF-7C) to block the IFN-induction function of IRF-7 that is detrimental for viral transformation. The work provides a novel relation of host/virus interactions, and has expanded our knowledge about IRFs in EBV transformation