3,105 research outputs found
Receiver Windowing Design for Narrowband Interference Mitigation in MB-OFDM UWB System
In 2005, the WiMedia Alliance working with the European Computer Manufacturers Association (ECMA) announced the establishment of the WiMedia MB-OFDM (Multiband Orthogonal Frequency Division Multiplexing) UWB radio platform as their global UWB standard. It was also chosen as the physical layer (PHY) of high data rate wireless specifications for high speed Wireless USB (W-USB), Bluetooth 3.0 and Wireless High-Definition Media Interface (HDMI). However, due to the low power and wide bandwidth nature of UWB systems, in-band narrowband interference (NBI) may hinder the receiver performance. This thesis presents an analysis of NBI impact on the MB-OFDM system for UWB communication. The intent of our analysis is to provide practical solutions for interference mitigation under different NBI models. In our work, a new receiver windowing for zero padding (ZP) OFDM system is proposed to reduce NBI spreading in the MB-OFDM UWB system. Simulations demonstrate the effectiveness of windowing under different NBI models.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Altered immunolocalization of FGF23 in murine femora metastasized with human breast carcinoma MDA-MB-231 cells
Introduction After the onset of bone metastasis, tumor cells appear to modify surrounding microenvironments for their benefit, and particularly, the levels of circulating fibroblast growth factor (FGF) 23 in patients with tumors have been highlighted. Materials and methods We have attempted to verify if human breast carcinoma MDA-MB-231 cells metastasized in the long bone of nu/nu mice would synthesize FGF23. Serum concentrations of calcium, phosphate (Pi) and FGF23 were measured in control nu/nu mice, bone-metastasized mice, and mice with mammary gland injected with MDA-MB-231 cells mimicking primary mammary tumors. Results and conclusions MDA-MB-231 cells revealed intense FGF23 reactivity in metastasized lesions, whereas MDA-MB-231 cells cultured in vitro or when injected into the mammary glands (without bone metastasis) showed weak FGF23 immunoreactivity. Although the bone-metastasized MDA-MB-231 cells abundantly synthesized FGF23, osteocytes adjacent to the FGF23-immunopositive tumors, unlike intact osteocytes, showed no FGF23. Despite significantly elevated serum FGF23 levels in bone-metastasized mice, there was no significant decrease in the serum Pi concentration when compared with the intact mice and mice with a mass of MDA-MB-231 cells in mammary glands. The metastasized femora showed increased expression and FGFR1 immunoreactivity in fibroblastic stromal cells, whereas femora of control mice showed no obvious FGFR1 immunoreactivity. Taken together, it seems likely that MDA-MB-231 cells synthesize FGF23 when metastasized to a bone, and thus affect FGFR1-positive stromal cells in the metastasized tumor nest in a paracrine manner
ASIC FFT processor for MB-OFDM UWB system
The physical layer (PHY) standard of Multi-band Orthogonal Frequency Division Multiplexing (MB-OFDM) Ultra Wideband (UWB) system was defined by ECMA International. In this standard, the data sampling rate from the analog-to-digital converter to the physical layer is up to 528 Msample/s. Therefore, it is a challenge to realize the physical layer of the UWB system-especially the components with high computational complexity in Very Large Scale Integration (VLSI) implementation. Fast Fourier Transform (FFT) block is one of these components. FFT plays an important role in Multi-band OFDM UWB system, which is the demodulation block of OFDM signals. The purpose of this project is to design an Application Specific Integrated Circuit (ASIC) FFT solution for this system. The specification is defined from the system analysis and literature research. All the design choices and considerations are concluded and explained.Based on the algorithm and architecture analysis, a novel Radix22Parallel processor is proposed, which is a small-area and low-power-consumption solution for MB-OFDM UWB system. Both Field Programmable Gate Array (FPGA) and ASIC targeted synthesis results of this architecture are presented.Electrical Engineering, Mathematics and Computer Scienc
Characterization of the tertiary structure of the de novo designed protein MB-1
Milk Bundle-1 (MB-1) is a de novo designed protein with 100 amino acids, having a molecular weight of 11.4 kilodaltons. MB-1 is enriched with 57% of selected essential amino acids (methionine, threonine, lysine and leucine), which are known to be limiting in dairy cattle. Recently, on the basis of a digestibility study, MB-1 was predicted to be unstable in rumen conditions.Characterization of the protein's structure was achieved using fluorescence spectroscopy (steady state measurements). MB-1 contains one tyrosine at position 62, expected to be in position "d" of helix III, in the hydrophobic core. Data obtained using fluorescence quenching indicates that the tyrosine is protected from the solvent in the putative hydrophobic core, as per design.Once it was established that MB-1 was not misfolded, further experiments were done to assess the fluidity of its hydrophobic core. For this, the amphiphillic dye ANSA was used. Results obtained for MB-1 compare favourably to those of many natural proteins, suggesting that MB-1 has achieved some degree of nativeness. Interestingly, MB-1 was found to exclude ANSA from its hydrophobic core more efficiently than all other de novo designed proteins reported to date.Finally, an analysis of folding thermodynamics of MB-1 was attempted. It was found that the fluorescence intensity of tyrosine was not sensitive to unfolding, making thermodynamic data impossible to obtain.Analysis of the data on MB-1 as compared to other natural proteins indicates that MB-1 is folded and compact. The lack of resistance to proteases must be caused by other factors other than the lack of compactness or misfolding. (Abstract shortened by UMI.).Source: Masters Abstracts International, Volume: 36-06, page: 1623.Adviser: Marc Beauregard
Stochastic Lie bracket (derivation, derivation) in MB-algebras
By a stochastic controller, we make stable the pseudo stochastic Lie bracket (derivation, derivation) in complex MB-algebras. Next, we get an approximation by a stochastic Lie bracket (derivation, derivation) and calculate the maximum error of the estimate. © 2020, The Author(s)
Weerkat: An extensible semantic Wiki
Wikis are Web applications that blur the boundaries between readers and authors, allowing non-technical people to author hypertexts through a web interface. A Semantic Wiki is a Wiki that attempts the same thing with the Semantic Web, allowing non-technical users to create semantic resources and/or ontologies. In this paper we characterise the different ways in which a Wiki might support the Semantic Web and present Weerkat, a modular and extensible Wiki that has ontological hypertext support. Key to this has been the design and development of a highly flexible Wiki architecture which allows easy modification and augmentation of functionality
Analysis of Safe and Effective Next-Generation Rail Signalling Systems using a FTA-SAN Approach
Moving Block (MB) and Virtual Coupling (VC) rail signalling will change current train operation paradigm by migrating vital equipment from trackside to onboard to reduce train separation and maintenance costs. Their actual deployment is however constrained by the industry’s need to identify configurations of MB and VC signalling equipment which can effectively guarantee safe train movements even under degraded operational conditions involving component faults. In this paper, we analyse the effectivity of MB and VC in safely supervising train separation under nominal and degraded conditions by using an innovative approach which combines Fault Tree Analysis (FTA) and Stochastic Activity Network (SAN). A FTA model of unsafe train movement is defined for both MB and VC capturing functional interactions and cause effect relations among the different signalling components. The FTA is then used as a basis to apportion signalling component failure rates needed to feed the SAN model. Effective MB and VC train supervision is analysed by means of SAN-based simulations in the specific scenario of an error in the Train Position Reporting (TPR) for five rail market segments featuring different traffic characteristics, namely high-speed, mainline, regional, urban and freight. Results show that the overall approach can support infrastructure managers, railway undertakings, and rail system suppliers in investigating effectiveness of MB and VC in safely supervising train movements in scenarios involving different types of degraded conditions and failure events. The proposed method can hence support the railway industry in identifying effective and safe design configurations of next-generation rail signalling systems.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport and Plannin
LA-MB-FTMW STUDIES OF SUGARS
Author Institution: Grupo de Espectroscopia Molecular (GEM). Edificio Quifima. Laboratorios de Espectroscopia y Bioespectroscopia. Parque Cientifico. Universidad de Valladolid, 47011 Valladolid. (Spain)Recently, rotational studies of biomolecules have entered in a new stage with the LA-MB-FTMW experiment. \textbf{11},617-627 (2009)and references therein} It combines laser ablation with Fourier transform microwave spectroscopy in supersonic jets overcoming the problems of thermal decomposition associated with conventional heating methods. This technique has been successfully applied to the study of monosaccarides. Three conformers of the prototype -D-glucose and other three for -D-glucose have been characterized for the first time in the gas phase
Informative sequence-based models for fragment distributions in ChIP-seq, RNA-seq and ChIP-chip data
Many high throughput sequencing protocols for RNA and DNA require that the
polynucleic acid is fragmented so that the identity of a limited number of nucleic acids of one
or both of the ends of the fragments can be determined by sequencing. The nucleic acid
sequence allows the fragment to be located within the genome, and the fragment distribution
can then be used for a variety of different purposes. In the case of DNA this includes
identifying the locations where specific proteins are bound to the genome. In the case of RNA
this includes quantifying the expression levels of different gene variants or transcripts. If the
locations of the polynucleic acid fragments are partly determined by the underlying nucleic
acid sequence this could bias any results derived from the data. Unfortunately, such sequence
dependencies have already been observed in the distribution of both RNA and DNA
fragments. Previous analyses of such data in order to reduce the bias have examined the role
of regional characteristics such as GC bias, or the bias towards a specific sequence at the start
of the fragments.
This thesis introduces a new method for modelling the bias which considers the degree
to which the nucleotide sequence affects the likelihood of a fragment originating at that
location. This shows that there is often not a single bias characteristic, but multiple,
alternative sequence biases that coexist within a single dataset. This also shows that the
nucleotide sequence immediately proximal to the fragment also has a significant effect on the
fragment likelihood. This new approach highlights characteristics that were previously hidden
and provides a more powerful basis for correcting such bias.
Multiple alternative sequence biases are observed when both RNA and DNA are
fragmented, but the more detailed information provided by the new technique shows in detail
how the characteristics are different for RNA and DNA and indicates that very different
molecular mechanisms are responsible for the biases in the two processes.
This thesis also shows how removing the effect of this bias in ChIP-seq experiments can
reveal more subtle features of the distribution of the fragments. This can provide information
on the nature of the binding between proteins and the DNA with per-nucleotide precision,
revealed through the change in likelihood of the DNA fragmenting at each position in the
binding site.
It is also shown how the model fitting technique developed to analyse sequence bias can
also be used to obtain additional information from the results of ChIP-chip experiments. The
approach is used to find the nucleotide sequence preference of DNA binding proteins, and
also the cooperative effects associated with binding at multiple binding sites in close
proximity
PESI - a taxonomic backbone for Europe
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The attached file is the published version of the article.NHM Repositor
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