Submicron ionography of nanostructures using a femtosecond-laser-driven-cluster-based source

An intense isotropic source of multicharged carbon and oxygen ions with energy above 300 keV and particle number >108 per shot was obtained by femtosecond Ti:Sa laser irradiation of submicron clusters. The source was employed for high-contrast contact ionography images with 600 nm spatial resolution. A variation in object thickness of 100 nm was well resolved for both Zr and polymer foils.

Nonlinear time series prediction based on a power-law noise model

In this paper we investigate the influence of a power-law noise model, also called noise, on the performance of a feed-forward neural network used to predict time series. We introduce an optimization procedure that optimizes the parameters the neural networks by maximizing the likelihood function based on the power-law model. We show that our optimization procedure minimizes the mean squared leading to an optimal prediction. Further, we present numerical results applying method to time series from the logistic map and the annual number of sunspots demonstrate that a power-law noise model gives better results than a Gaussian model.

Job strain and leisure-time physical activity in female and male public sector employees

Background. High work stress could decrease physical activity but the evidence of the relationship has remained equivocal, The present study examined the association between job strain and leisure-time physical activity in a large sample of employees.

P2Y(1) antagonists: Combining receptor-based modeling and QSAR for a quantitative prediction of the biological activity based on consensus scoring

P2Y(1) is an ADP-activated G protein-coupled receptor (GPCR). Its antagonists impede platelet aggregation in vivo and are potential antithrombotic agents. Combining ligand and structure-based modeling we generated a consensus model (LIST-CM) correlating antagonist structures with their potencies. We docked 45 antagonists into our rhodopsin-based human P2Y(1) homology model and calculated docking scores and free binding energies with the Linear Interaction Energy (LIE) method in continuum-solvent. The resulting alignment was also used to build QSAR based on CoMFA, CoMSIA, and molecular descriptors. To benefit from the strength of each technique and compensate for their limitations, we generated our LIST-CM with a PLS regression based on the predictions of each methodology. A test set featuring untested substituents was synthesized and assayed in inhibition of 2-MeSADP-stimulated PLC activity and in radioligand binding. LIST-CM outperformed internal and external predictivity of any individual model to predict accurately the potency of 75% of the test set.

Real-time GPU color-based segmentation of football players

In this paper, we propose a multi-camera application capable of processing high resolution images and extracting features based on colors patterns over graphic processing units (GPU). The goal is to work in real time under the uncontrolled environment of a sport event like a football match. Since football players are composed for diverse and complex color patterns, a Gaussian Mixture Models (GMM) is applied as segmentation paradigm, in order to analyze sport live images and video. Optimization techniques have also been applied over the C++ implementation using profiling tools focused on high performance. Time consuming tasks were implemented over NVIDIA's CUDA platform, and later restructured and enhanced, speeding up the whole process significantly. Our resulting code is around 4-11 times faster on a low cost GPU than a highly optimized C++ version on a central processing unit (CPU) over the same data. Real time has been obtained processing until 64 frames per second. An important conclusion derived from our study is the scalability of the application to the number of cores on the GPU. © 2011 Springer-Verlag.

Development of Novel Activity-Based Probes for the Detection of Serine Proteases

Cystic Fibrosis (CF) is a genetic disease featuring a chronic cycle of inflammation and infection in the airways of sufferers. Mutations lead to altered ion transport, which in turn causes dehydrated airways and reduced mucociliary clearance which predisposes the patient to infection, resulting in a severe immune response and tissue destruction (1). Airway dehydration is primarily caused by the hyperabsorption of sodium by the epithelial sodium channel (ENaC) (2). ENaC is activated by the action of a number of predominantly trypsin-like Channel Activating Proteases (CAPs) including prostasin, matriptase and furin (3). Additional proteases known to activate ENaC include human airway trypsin (3), plasmin, neutrophil elastase and chymotrypsin (4).

Activity profiling is a valuable technique which involves the use of small inhibitory molecules called Activity-Based Probes (ABPs) which can be used to covalently label the active site of proteases and provide a range of information regarding its structure, catalytic mechanism, location and function within biological systems. The development of novel ABPs for CAPs, would enhance understanding of the role of these proteases in CF airways disease and in particular their role in ENaC activation and airway dehydration. This project investigates the application of a range of novel broad-spectrum ABPs targeting the various subclasses of serine proteases, to include those proteases involved in ENaC activation. Additionally, the application of more selective ABPs in detecting specific serine proteases is investigated.

Compounds were synthesised by Solid-Phase Peptide Synthesis (SPPS) using a standard Fmoc/tBu strategy. Kinetic evaluation of synthesised ABPs against various serine proteases was determined by fluorogenic steady-state enzyme assays. Furthermore, application of ABPs and confirmation of irreversible nature of the compounds was carried out through SDS-PAGE and electroblotting techniques.

Synthesised compounds showed potent irreversible inhibition of serine proteases within their respective targeting class (NAP855 vs Trypsin k3/Ki = 2.60 x 106 M-1 min-1, NFP849 vs Chymotrypsin k3/Ki = 1.28 x 106 M-1 min-1 and NVP800 vs Neutrophil Elastase k3/Ki = 6.41 x 104 M-1 min-1). Furthermore ABPs showed little to no cross-reactivity between classes and so display selectivity between classes. The irreversible nature of compounds was further demonstrated through labelling of proteases, followed by separation and detection via SDS-PAGE and electroblotting techniques. Targeted labelling of active proteases only, was demonstrated by failure of ABPs to detect previously inactivated proteases. Extension of the substrate recognition site within probes resulted in an increased potency and selectivity in the detection of the target proteases. Successful detection of neutrophil elastase from CF sputum samples by NVP800, demonstrated the application of compounds within biological samples and their potential use in identifying further proteases involved in ENaC activation and airway dehydration in CF patients.

A Continuous Time Markov Chain Based Sequential Analytical Approach for Composite Power System Reliability Assessment

This paper proposes a continuous time Markov chain (CTMC) based sequential analytical approach for composite generation and transmission systems reliability assessment. The basic idea is to construct a CTMC model for the composite system. Based on this model, sequential analyses are performed. Various kinds of reliability indices can be obtained, including expectation, variance, frequency, duration and probability distribution. In order to reduce the dimension of the state space, traditional CTMC modeling approach is modified by merging all high order contingencies into a single state, which can be calculated by Monte Carlo simulation (MCS). Then a state mergence technique is developed to integrate all normal states to further reduce the dimension of the CTMC model. Moreover, a time discretization method is presented for the CTMC model calculation. Case studies are performed on the RBTS and a modified IEEE 300-bus test system. The results indicate that sequential reliability assessment can be performed by the proposed approach. Comparing with the traditional sequential Monte Carlo simulation method, the proposed method is more efficient, especially in small scale or very reliable power systems.

Label-free Detection of Microcystin-LR in Waters Using Real-Time Potentiometric Biosensors Based on Single-Walled Carbon Nanotubes Imprinted Polymers

Microcystin-LR (MC-LR) is a dangerous toxin found in environmental waters, quantified by high performance liquid chromatography and/or enzyme-linked immunosorbent assays. Quick, low cost and on-site analysis is thus required to ensure human safety and wide screening programs. This work proposes label-free potentiometric sensors made of solid-contact electrodes coated with a surface imprinted polymer on the surface of Multi-Walled Carbon NanoTubes (CNTs) incorporated in a polyvinyl chloride membrane. The imprinting effect was checked by using non-imprinted materials. The MC-LR sensitive sensors were evaluated, characterized and applied successfully in spiked environmental waters. The presented method offered the advantages of low cost, portability, easy operation and suitability for adaptation to flow methods.

Examining current facilitative practices and projections of activity-based physical education degree programs regarding the participation of individuals with disabilties /

Individuals with disabiliiies are increasingly accessing post secondary education opportunities to further develop their educational and career goals. This study examines the current facilitative practices of Canadian university activity-based physical education degree programs on the participation of individuals with disabilities. A critical orientation and descriptive/interpretative approach allows insight into unique stories and experiences of physical education practitioners and special needs professionals as they attempt to provide equitable educational experiences within a least restrictive environment. Leading practitioners are used to triangulate and strengthen the validity of the data while providing direction and advocacy for future development and inclusion of individuals with disabilities. The study concludes with seven recommendations, each providing university activity-based physical education degree programs with viable opportunities for helping create equitable opportunities for individuals with disabilities.

Leisure-time physical activity in individuals with osteoporosis : associations with psychological well-being

With approximately 16% of the Canadian population living with osteoporosis, and rates expected to increase (Osteoporosis Canada, 2009), cost-effective treatment modalities that improve bone health and psychological well-being reflect an important public health agenda. Physical activity has been implicated as one non-pharmaceutical mechanism to help improve psychological well-being in the general population (Fox, Stathi, McKenna, & Davis, 2007) and in people diagnosed with osteoporosis (Osteoporosis Canada, 2007). The purpose of this investigation was to determine the association between leisure-time physical activity (LTP A) and well-being in people diagnosed with osteoporosis. A secondary purpose, using Basic Needs Theory (BNT; Deci & Ryan, 2002) was to determine if the fulfillment of three psychological needs (i.e., competence, autonomy and relatedness) mediated the relationship between LTP A and well-being. People diagnosed with osteoporosis (N= 190; Mage = 68.14; SDage = 11.54) were asked to complete a battery of questionnaires assessing L TP A, hedonic and eudaimonic well-being and perceived psychological need satisfaction in physical activity contexts. Bivariate correlations revealed a pattern of negligible (r's -0.02 to 0.35) to small correlations between LTP A and well-being with contextual positive affect (r = 0.24) and subjective vitality (r = 0.22) demonstrating statistical significance (p < .01). Results of the multiple mediation analysis indicated that perceived satisfaction of the three psychological needs mediated the relationship between LTPA and well-being with perceived competence emerging as a unique mediator. As such, LTP A was positively associated with well-being in people who are diagnosed with osteoporosis, and the fulfillment of the three psychological needs may be the mechanism through which this 111 effect is carried. Health promotion specialists and practitioners should encourage patients with osteoporosis to engage in LTP A, and support their needs for competence, autonomy and relatedness. Practical implications for researchers and health promotion specialists are discussed in terms ofthe results of this investigation.

A sistematização da gestão baseada em atividades (ABM) - Activity Based Management - para aplicação na área hospitalar : caso Centro de Terapia Intensiva de um hospital universitário público

Esta pesquisa tem por base a aplicação da Gestão Baseada em Atividades ABM - Activity Based Management -, em um Centro de Terapia Intensiva (CTI) de um hospital universitário público. Tem corno objetivo aperfeiçoar a prática gerencial do CTI, estabelecendo relações de causa e efeito no uso dos recursos (humanos, tecnológicos, materiais), permitindo efetuar mudanças para sua melhor utilização, maximizando beneficios a toda organização. O enfoque metodológico foi a pesquisa qualitativa e quantitativa, sendo que o Centro de Terapia Intensiva foi o foco de análise na implementação do ABM. As etapas envolvidas na condução deste trabalho foram a exploratória e a dos seminários, orientadas pela técnica de Thiollent (2000). O trabalho propõe urna sistemática de aplicação do ABM em CTI. A partir de sua aplicação no caso específico - CTI de um hospital público de Porto Alegre - discute os principais benefícios e limitações, bem corno as informações gerenciais proporcionadas. De acordo com análise do conteúdo e os resultados obtidos, pôde-se alicerçar o conhecimento teórico e prático do modelo de gestão proposto, estabelecendo urna nova dimensão na gestão de recursos na área hospitalar, com mais eficiência, assegurando a captura de todo potencial de melhoria identificado.

Activity Based Cost (ABC) : qual a importância deste conceito para o executivo de uma operação?

Trata da importância da informação de custos efetivamente gerenciais para as equipes operacionais das empresas que muito poderiam contribuir para a redução de custos e aumento do volume de vendas se soubessem com maior discernimento a composição dos custos dos produtos com os quais trabalham, sua variabilidade em função da variação do volume de vendas e produção, e conseqüentemente a relação destes custos com as demais variações de níveis de atividade de outros produtos da empresa. Além das ações estratégicas que poderiam ser tomadas, a equipe comercial poderia discutir a efetiva agregação de valor de alguns Itens de seu custo para o cliente e, eventualmente, sugerir a alteração de seu produto visando proporcionar melhor aproveitamento da relação custo - benefício à empresa e ao cliente