A low-complexity lattice-based low-PAR transmission scheme for DSL channels

This paper presents a new low-complexity multicarrier modulation (MCM) technique based on lattices which achieves a peak-to-average power ratio (PAR) as low as three. The scheme can be viewed as a drop in replacement for the discrete multitone (DMT) modulation of an asymmetric digital subscriber line modem. We show that the lattice-MCM retains many of the attractive features of sinusoidal-MCM, and does so with lower implementation complexity, O(N), compared with DMT, which requires O(N log N) operations. We also present techniques for narrowband interference rejection and power profiling. Simulation studies confirm that performance of the lattice-MCM is superior, even compared with recent techniques for PAR reduction in DMT.

Structural basis for control of secondary vessels in the long-finned eel, Anguilla reinhardtii

Histological sections of primary segmental arteries and associated interarterial anastomoses and secondary vessels from the long-finned eel Anguilla reinhardtii were examined by light and transmission electron microscopy. Interarterial anastomoses were found to originate from the primary vasculature as depressions through the tunica intima and media, from where they ran perpendicularly to the adventitial layer, before coiling extensively. From here the anastomoses travelled a relatively linear path in the outer margin of the adventitia to anastomose with a secondary vessel running in parallel with the primary counterpart. In contrast to findings from other species, secondary vessels had a structure quite similar to that of primary vessels; they were lined by endothelial cells on a continuous basement membrane, with a single layer of smooth muscle cells surrounding the vessel. Smooth muscle cells were also found in the vicinity of interarterial anastomoses in the adventitia, but these appeared more longitudinally orientated. The presence of smooth muscle cells on all aspects of the secondary circulation suggests that this vascular system is regulated in a similar manner as the primary vascular system. Because interarterial anastomoses are structurally integrated with the primary vessel from which they originate, it is anticipated that flow through secondary vessels to some extent is affected by the vascular tone of the primary vessel. Immunohistochemical studies showed that primary segmental arteries displayed moderate immunoreactivity to antibodies against 5-hydroxytryptamine and substance P, while interarterial anastomoses and secondary vessels showed dense immunoreactivity. No immunoreactivity was observed on primary or secondary arteries against neuropeptide Y or calcitonin gene-related peptide.

Short-term peaks in glucose promote renal fibrogenesis independently of total glucose exposure

Postprandial hyperglycemia is implicated as a risk factor predisposing to vascular complications. This study was designed to assess recurrent short-term increases in glucose on markers of renal fibrogenesis. Human renal cortical fibroblasts were exposed to fluctuating short-term (2 h) increases to 15 mM D-glucose, three times a day over 72 h, on a background of 5 mM D-glucose. To determine whether observed changes were due to fluctuating osmolality, identical experiments were undertaken with cells exposed to L-glucose. Parallel experiments were performed in cells exposed to 5 mM D-glucose and constant exposure to either 15 or 7.5 mM D-glucose. Fluctuating D-glucose increased extracellular matrix, as measured by proline incorporation ( P < 0.05), collagen IV ( P < 0.005), and fibronectin production ( P < 0.001), in association with increased tissue inhibitor of matrix metalloproteinase (MMP) ( P < 0.05). Sustained exposure to 15 mM D-glucose increased fibronectin ( P < 0.001), in association with increased MMP-2 ( P = 0.01) and MMP-9 activity ( P < 0.05), suggestive of a protective effect on collagen matrix accumulation. Transforming growth factor-beta(1) (TGF-beta(1)) mRNA was increased after short-term (90 min) exposure to 15 mM glucose (P < 0.05) and after 24-h exposure to 7.5 mM ? ( P < 0.05). Normalization of TGF-beta(1) secretion occurred within 48 h of constant exposure to an elevated glucose. Fluctuating L-glucose also induced TGF-beta(1) mRNA and a profibrotic profile, however, to a lesser extent than observed with exposure to fluctuating D-glucose. The results suggest that exposure to fluctuating glucose concentrations increases renal interstitial fibrosis compared with stable elevations in D-glucose. The effects are, in part, due to the inherent osmotic changes.

Aphasia websites: An examination of their quality and communicative accessibility

Background: Studies have examined Internet use as a source of information by various populations, however no study has examined the quality and accessibility of websites for people with aphasia, or their use of such sites. Aims: This study aimed to describe the quality, communicative accessibility, and readability of a sample of aphasia websites and to determine whether sites preferred by people with aphasia were those rated highly on measures of accessibility and quality. The perceptions of people with aphasia regarding the accessibility of the sites were compared with those of speech pathologists. The relationship between the quality and communicative accessibility of websites was analysed. Factors that may influence use of the Internet by people with aphasia and speech pathologists were explored. Methods & Procedures: Tools for measuring quality and communicative accessibility were developed and a sample of five websites was selected. Two participant groups (18 speech pathologists and 6 people with aphasia) assessed aphasia websites in terms of communicative accessibility. Speech pathologists also rated website quality. Spearman's rho was used to determine levels of agreement between variables. Outcomes & Results: People with aphasia and speech pathologists showed minimal agreement on their perceptions of communicative accessibility. However, when the preferences of websites (Aphasia Help and Speakability) were of a very high standard. There was a weak relationship between quality and communicative accessibility, however it was not statistically significant. Conclusions: Accessible websites are not necessarily of high quality, and quality websites are not guaranteed to be easily accessible. People with aphasia did not agree with speech pathologists as to what makes a good aphasia website. Therefore, people with aphasia should be involved in the design of aphasia websites since they are often the intended users. If Internet use by people with aphasia increases in line with other health populations, speech pathologist need to have the skills and confidence to recommend appropriate sites to their clients.

Dynamic rupture in a 3-D particle-based simulation of a rough planar fault

An appreciation of the physical mechanisms which cause observed seismicity complexity is fundamental to the understanding of the temporal behaviour of faults and single slip events. Numerical simulation of fault slip can provide insights into fault processes by allowing exploration of parameter spaces which influence microscopic and macroscopic physics of processes which may lead towards an answer to those questions. Particle-based models such as the Lattice Solid Model have been used previously for the simulation of stick-slip dynamics of faults, although mainly in two dimensions. Recent increases in the power of computers and the ability to use the power of parallel computer systems have made it possible to extend particle-based fault simulations to three dimensions. In this paper a particle-based numerical model of a rough planar fault embedded between two elastic blocks in three dimensions is presented. A very simple friction law without any rate dependency and no spatial heterogeneity in the intrinsic coefficient of friction is used in the model. To simulate earthquake dynamics the model is sheared in a direction parallel to the fault plane with a constant velocity at the driving edges. Spontaneous slip occurs on the fault when the shear stress is large enough to overcome the frictional forces on the fault. Slip events with a wide range of event sizes are observed. Investigation of the temporal evolution and spatial distribution of slip during each event shows a high degree of variability between the events. In some of the larger events highly complex slip patterns are observed.

Focusing in on structural genomics: The University of Queensland structural biology pipeline

The flood of new genomic sequence information together with technological innovations in protein structure determination have led to worldwide structural genomics (SG) initiatives. The goals of SG initiatives are to accelerate the process of protein structure determination, to fill in protein fold space and to provide information about the function of uncharacterized proteins. In the long-term, these outcomes are likely to impact on medical biotechnology and drug discovery, leading to a better understanding of disease as well as the development of new therapeutics. Here we describe the high throughput pipeline established at the University of Queensland in Australia. In this focused pipeline, the targets for structure determination are proteins that are expressed in mouse macrophage cells and that are inferred to have a role in innate immunity. The aim is to characterize the molecular structure and the biochemical and cellular function of these targets by using a parallel processing pipeline. The pipeline is designed to work with tens to hundreds of target gene products and comprises target selection, cloning, expression, purification, crystallization and structure determination. The structures from this pipeline will provide insights into the function of previously uncharacterized macrophage proteins and could lead to the validation of new drug targets for chronic obstructive pulmonary disease and arthritis. (c) 2006 Elsevier B.V. All rights reserved.

Investigations into the effect of LOS signal blocking on capacity of an indoor MIMO system

In indoor environments the properties of communication channel are affected by the presence of various objects which block the Line Of Sight signal propagation. For example, this occurs because of presence of movement of humans and furniture. In this paper, the effect of reflection and scattering due to the presence of such objects is studied with respect to the capacity of a multiple input multiple output (MIMO) wireless system. The carried out investigations are performed by applying a simple electromagnetic model, in which transmitting and receiving antennas of MIMO system, as well as signal blocking objects, are represented by wire dipoles. In order to provide a fair assessment, calculations of MIMO capacity are performed under both fixed transmitted power and fixed received power conditions.

A CONSTRU����O DA IDENTIDADE DO SER PROFISSIONAL SECRET��RIO NA REGI��O DO GRANDE ABC

A regi��o do Grande ABC �� caracterizada por ser local que retrata, de forma singular, os conflitos, as mudan��as e o impacto da globaliza����o no Pa��s e no mundo. Diferentes setores, articulados, constru��ram o Planejamento Regional para a regi��o, que se deparava com a flexibiliza����o, o desemprego estrutural e a diminui����o nos postos de trabalho das grandes montadoras, de ind��strias de autope��as, entre outras, e descobriu caminhos de enfrentamento para o processo que avassalou o Brasil e o mundo. Isso exigiu a profissionaliza����o de quem ocupava a fun����o de Secret��rio, para atender ao perfil das multinacionais. A partir da��, o Secretariado Executivo vem se consolidando como uma profiss��o de car��ter inteligente e intelectual, considerado como anal��tico-simb��lico. O Secret��rio rompeu com seu antigo perfil, enfrentando a concorr��ncia de profissionais de outras ��reas, e desempenha hoje um papel de assessoria adjunta, gerenciando processos e facilitando tomadas de decis��o. �� um profissional de forma����o intelectual diferenciada, com compet��ncias t��cnicas, comportamentais e estrat��gicas. Assim, esta pesquisa teve como objetivo analisar o processo de constru����o da identidade do ser profissional Secret��rio na regi��o do Grande ABC; levantar os espa��os ocupados por esse profissional, atrav��s de mapeamento dos postos que ocupa, e construir uma linha do tempo dessa profiss��o na regi��o. Para atender aos objetivos, foi utilizada pesquisa documental, a constru����o de uma linha do tempo e a hist��ria oral tem��tica, procedendo-se �� coleta e �� an��lise dos dados de sete profissionais Secret��rios atuantes na regi��o do Grande ABC. O di��logo interdisciplinar entre teoria e os discursos evidenciou que ainda existe um estere��tipo cultural quanto �� profiss��o nas organiza����es, mas h�� um respeito, ainda que velado, dos superiores e colegas, conquistado por sua persist��ncia e profissionaliza����o. Os resultados demonstram que a identidade do ser profissional Secret��rio �� constru��da em suas experi��ncias vividas no passado e no presente, o que lhe proporciona um esbo��o de valores individuais e profissionais que s��o revistos nas diversas organiza����es em que atuam ou atuaram e dentro do contexto regional estudado, gerando varia����es em suas identidades.(AU)

A Interpreta����o de Isa��as pelo Evangelho de Mateus: uma Abordagem a partir de Mateus 4.14-16 Por Mauro Filgueiras Filho

Esta disserta����o tem por foco apresentar o m��todo hermen��utico tipol��gico como ferramenta proposta para compreender a leitura realizada pelo evangelho de Mateus 4.15-16 da profecia de Isa��as 8.23 9.1 [TM]. O texto receber�� aten����o a partir do Texto Massor��tico e da Septuaginta, sempre em compara����o com o texto grego de Mateus. Por conseguinte, o contexto judaico do primeiro s��culo ser�� estudado para compreender mais amplamente o ambiente em que o evangelista possivelmente se encontrava para escrever o seu evangelho. As t��cnicas de interpreta����o contempladas em paralelo com a tipologia, consideradas de maior import��ncia para este trabalho s��o: tr��s t��cnicas rab��nicas, isto ��, pesher, midrah e gezerah shavah, e outras tr��s t��cnicas de interpreta����o eminentemente crist��s, isto ��, duplo-cumprimento, o sensus plenior e a tipologia. Por fim, o estudo comparativo do juda��smo do primeiro s��culo e das t��cnicas de interpreta����o resultar�� na escolha da interpreta����o tipol��gica, mas sem um radical rompimento com as demais escolas, pelo contr��rio, conflitando com alguns apontamentos dos Rolos do Mar Morto e seu apocalipticismo. A interpreta����o tipol��gica se ocupar�� com as semelhan��as entre o texto veterotestament��rio e o neotestament��rio, bem como semelhan��as que poderiam compor um cen��rio mais abrangente. Ser��o considerados tr��s temas comuns dos dois textos que estabelecem um v��nculo entre ambos, ou seja, a geografia, os gentios e a interpreta����o da luz.

CONSTRU����ES IMAGIN��RIAS NO CONTEXTO DE UM FEN��MENO MUSICAL DE MASSA: O CASO DO CANTOR MICHEL TEL��

Estudo sobre o processo de constru����o imagin��ria do p��blico de g��nero feminino ao consumir os produtos dos fen��menos musicais de massa, no Brasil. Tendo como base o caso do sucesso do cantor Michel Tel��, representante do g��nero musical sertanejo universit��rio, o objetivo �� compreender o processo de constru����o imagin��ria que permeia a rela����o do p��blico feminino (f��s) e consumo do g��nero musical sertanejo universit��rio, a partir do discurso do cantor Michel Tel��. Para tal, ser�� tomado referencial te��rico do campo dos Estudos Culturais em di��logo com estudos sobre imagin��rio e m��sica de massa. A an��lise do discurso, de linha francesa, �� a metodologia empregada em duas inst��ncias para se testar as reflex��es constru��das com a base te��rica: a priori, a partir de um processo de observa����o participante, durante um espet��culo do artista, em que ser�� observada a intera����o entre fen��meno e p��blico, no momento de execu����o da sua m��sica Ai, se eu te pego! ; e, doravante, o discurso do m��sico �� analisado, por meio de entrevistas realizadas em programas televisivos. Um question��rio aplicado a uma amostra entre o p��blico feminino apreciador do cantor e de suas m��sicas contribui ainda no aprofundamento da reflex��o. Resulta desta pesquisa a compreens��o da proemin��ncia do discurso ao conte��do. Desta maneira, a import��ncia maior se encontra na forma com que o cantor dialoga com seu p��blico, por meio da imagem que ele constr��i em torno de si.

Service encounter conceptualisation:employees' service behaviours and customers' service quality perceptions

The enhancement of service quality is an area of optimal managerial relevance that has, to date, received minimal attention in the literature. Because customers' service quality evaluations are based almost entirely upon the behaviours of frontline employees, organisations rely heavily upon these employees to improve overall service quality provision. However, much of the literature looking at service quality enhancement lacks detail when examining the impact of employee service-related behaviours on customers' service quality perceptions. As a result, this paper comprehensively conceptualises those front-line employee behaviours which are the most likely to enhance customers' service quality perceptions. This conceptualisation is grounded in an extensive review of the services marketing literature, pooling together previously disparate research strands. Formal hypotheses are presented. Implications and future research directions are also discussed.

Fast response static var generator for improving the power system performance of an electric arc furnace (EAF)

Cascaded multilevel inverters-based Static Var Generators (SVGs) are FACTS equipment introduced for active and reactive power flow control. They eliminate the need for zigzag transformers and give a fast response. However, with regard to their application for flicker reduction in using Electric Arc Furnace (EAF), the existing multilevel inverter-based SVGs suffer from the following disadvantages. (1) To control the reactive power, an off-line calculation of Modulation Index (MI) is required to adjust the SVG output voltage. This slows down the transient response to the changes of reactive power; and (2) Random active power exchange may cause unbalance to the voltage of the d.c. link (HBI) capacitor when the reactive power control is done by adjusting the power angle d alone. To resolve these problems, a mathematical model of 11-level cascaded SVG, was developed. A new control strategy involving both MI (modulation index) and power angle (d) is proposed. A selected harmonics elimination method (SHEM) is taken for switching pattern calculations. To shorten the response time and simplify the controls system, feed forward neural networks are used for on-line computation of the switching patterns instead of using look-up tables. The proposed controller updates the MI and switching patterns once each line-cycle according to the sampled reactive power Qs. Meanwhile, the remainder reactive power (compensated by the MI) and the reactive power variations during the line-cycle will be continuously compensated by adjusting the power angles, d. The scheme senses both variables MI and d, and takes action through the inverter switching angle, qi. As a result, the proposed SVG is expected to give a faster and more accurate response than present designs allow. In support of the proposal there is a mathematical model for reactive powered distribution and a sensitivity matrix for voltage regulation assessment, MATLAB simulation results are provided to validate the proposed schemes. The performance with non-linear time varying loads is analysed and refers to a general review of flicker, of methods for measuring flickers due to arc furnace and means for mitigation.

Switching and generation of ultrashort pulses using all-fibre devices

Serial and parallel interconnection of photonic devices is integral to the construction of any all-optical data processing system. This thesis presents results from a series of experiments centering on the use of the nonlinear-optical loop mirror (NOLM) switch in architectures for the manipulation and generation of ultrashort pulses. Detailed analysis of soliton switching in a single NOLM and cascade of two NOLM's is performed, centering on primary limitations to device operation, effect of cascading on amplitude response, and impact of switching on the characteristics of incident pulses. By using relatively long input pulses, device failure due to stimulated Raman generation is postponed to demonstrate multiple-peaked switching for the first time. It is found that while cascading leads to a sharpening of the overall switching characteristic, pulse spectral and temporal integrity is not significantly degraded, and emerging pulses retain their essential soliton character. In addition, by including an asymmetrically placed in-fibre Bragg reflector as a wavelength selective loss element in the basic NOLM configuration, both soliton self-switching and dual-wavelength control-pulse switching are spectrally quantised. Results are presented from a novel dual-wavelength laser configuration generating pulse trains with an ultra-low rms inter-pulse-stream timing jitter level of 630fs enabling application in ultrafast switching environments at data rates as high as 130GBits/s. In addition, the fibre NOLM is included in architectures for all-optical memory, demonstrating storage and logical inversion of a 0.5kByte random data sequence; and ultrafast phase-locking of a gain-switched distributed feedback laser at 1.062GHz, the fourteenth harmonic of the system baseband frequency. The stringent requirements for environmental robustness of these architectures highlight the primary weaknesses of the NOLM in its fibre form and recommendations to overcome its inherent drawbacks are presented.

Visual data mining: integrating machine learning with information visualization

Today, the data available to tackle many scientific challenges is vast in quantity and diverse in nature. The exploration of heterogeneous information spaces requires suitable mining algorithms as well as effective visual interfaces. Most existing systems concentrate either on mining algorithms or on visualization techniques. Though visual methods developed in information visualization have been helpful, for improved understanding of a complex large high-dimensional dataset, there is a need for an effective projection of such a dataset onto a lower-dimension (2D or 3D) manifold. This paper introduces a flexible visual data mining framework which combines advanced projection algorithms developed in the machine learning domain and visual techniques developed in the information visualization domain. The framework follows Shneiderman���s mantra to provide an effective user interface. The advantage of such an interface is that the user is directly involved in the data mining process. We integrate principled projection methods, such as Generative Topographic Mapping (GTM) and Hierarchical GTM (HGTM), with powerful visual techniques, such as magnification factors, directional curvatures, parallel coordinates, billboarding, and user interaction facilities, to provide an integrated visual data mining framework. Results on a real life high-dimensional dataset from the chemoinformatics domain are also reported and discussed. Projection results of GTM are analytically compared with the projection results from other traditional projection methods, and it is also shown that the HGTM algorithm provides additional value for large datasets. The computational complexity of these algorithms is discussed to demonstrate their suitability for the visual data mining framework.

Characterisation of the plasma membrane subproteome of bloodstream form Trypanosoma brucei

Proteome analysis by conventional approaches is biased against hydrophobic membrane proteins, many of which are also of low abundance. We have isolated plasma membrane sheets from bloodstream forms of Trypanosoma brucei by subcellular fractionation, and then applied a battery of complementary protein separation and identification techniques to identify a large number of proteins in this fraction. The results of these analyses have been combined to generate a subproteome for the pellicular plasma membrane of bloodstream forms of T. brucei as well as a separate subproteome for the pellicular cytoskeleton. In parallel, we have used in silico approaches to predict the relative abundance of proteins potentially expressed by bloodstream form trypanosomes, and to identify likely polytopic membrane proteins, providing quality control for the experimentally defined plasma membrane subproteome. We show that the application of multiple high-resolution proteomic techniques to an enriched organelle fraction is a valuable approach for the characterisation of relatively intractable membrane proteomes. We present here the most complete analysis of a protozoan plasma membrane proteome to date and show the presence of a large number of integral membrane proteins, including 11 nucleoside/nucleobase transporters, 15 ion pumps and channels and a large number of adenylate cyclases hitherto listed as putative proteins.