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1.
Two hundred thirty-three newly enrolled medical and nursing students at the American University of Beirut, Lebanon, were tested for antibodies to measles and mumps. Antibodies to measles were detected in 95% of the sample, and antibodies to mumps in 84% of the sample. Susceptible individuals were appropriately immunized.  相似文献   
2.
In this paper we present a novel methodology for sequence classification, based on sequential pattern mining and optimization algorithms. The proposed methodology automatically generates a sequence classification model, based on a two stage process. In the first stage, a sequential pattern mining algorithm is applied to a set of sequences and the sequential patterns are extracted. Then, the score of every pattern with respect to each sequence is calculated using a scoring function and the score of each class under consideration is estimated by summing the specific pattern scores. Each score is updated, multiplied by a weight and the output of the first stage is the classification confusion matrix of the sequences. In the second stage an optimization technique, aims to finding a set of weights which minimize an objective function, defined using the classification confusion matrix. The set of the extracted sequential patterns and the optimal weights of the classes comprise the sequence classification model. Extensive evaluation of the methodology was carried out in the protein classification domain, by varying the number of training and test sequences, the number of patterns and the number of classes. The methodology is compared with other similar sequence classification approaches. The proposed methodology exhibits several advantages, such as automated weight assignment to classes using optimization techniques and knowledge discovery in the domain of application.
Dimitrios I. FotiadisEmail:
  相似文献   
3.
In this work, an efficient method for spot addressing in images, which are generated by the scanning of hexagonal structured microarrays, is proposed. Initially, the blocks of the image are separated using the projections of the image. Next, all the blocks of the image are processed separately for the detection of each spot. The spot addressing procedure begins with the detection of the high intensity objects, which are probably the spots of the image. Next, the Growing Concentric Hexagon algorithm, which uses the properties of the hexagonal grid, is introduced for the detection of the non-hybridized spots. Finally, the Voronoi diagram is applied to the centers of the detected spots for the gridding of the image. The method is evaluated using spots generated from the scanning of the Beadchip of Illumina, which is used for the detection of Single Nucleotide Polymorphisms in the human genome, and uses hexagonal structure for the location of the spots. For the evaluation, the detected centers for each of the spot in the image are compared to the centers of the annotation, obtaining up to 98% accuracy for the spot addressing procedure.  相似文献   
4.
The increasing energy challenges faced, in particular, by isolated communities, such as insular communities, call for an integrated, flexible and easy-to-apply methodology aiming at providing a list of renewable energy sources) (RES) projects capable to reduce green house gas (GHG) emissions, satisfy future energy forecasts and reach the objectives of international/national energy directives and obligations, as, for example, the ones set by the Kyoto Protocol by 2010. The EU project EMERGENCE 2010 developed such a methodology that is implemented here in the case study of wind parks in the Dodecanese islands in Greece. The results obtained consist of a final list of financially viable RES wind projects, for which various barriers have been previously identified and assessed. The additional advantages of the proposed methodology is that besides providing as an end result a comprehensive list of RES projects adopted to specific criteria and regional priorities, it also allows space for involving – from early stages – the local community and stakeholders in the decision-making process (participatory planning); in this way, the EMERGENCE 2010 methodology may assist towards the RES promotion and public acceptance, the profitability of RES investments and the regional sustainable development.  相似文献   
5.
Wood smoke exposure has been associated with adverse respiratory health outcomes, with much of the current research focused on wood smoke from domestic heating and cooking. This study examined the association between respiratory symptoms and outdoor wood smoke in Launceston, Tasmania, where ~ 30% of homes use wood burners for domestic heating. This ecological study examined data from participants of the 2004 Tasmanian Longitudinal Health Study postal survey and compared the prevalence of respiratory symptoms in Launceston (n = 601) with that in Hobart (n = 1071), a larger Tasmanian city with much less wood smoke. Multivariate logistic regression models were used to investigate the associations of interest while adjusting for gender, atopy, history of allergic disease and current smoking status. There were no significant differences in symptom prevalence between Launceston and Hobart. Two subgroup analyses, which examined participants with pre-existing chronic respiratory disease, and those who reported actively using a wood burner in their home, also did not find significant differences. Any impact of wood smoke on non-specific respiratory symptoms might have been overshadowed by other important determinants of respiratory health, such as vehicle exhaust and tobacco smoking, or were too small to have been detected. However, the lack of detectable differences in symptom prevalence might also reflect the success of regulatory action by local governments to reduce wood smoke emissions in Launceston. The results of other epidemiological studies support an association between ambient wood smoke exposure and adverse respiratory health. Further investigations of wood smoke exposure in Australian settings are needed to investigate the lack of significant associations found in this study, especially studies of indoor air quality and health impacts in children and elderly populations.  相似文献   
6.
Soft materials comprising low‐molecular‐weight organic molecules are attracting increasing interest because of their importance in the development of a number of emerging areas in nanoscience and technology, including molecular electronics, nanosystems for energy conversion, and devices in the widest sense. Their interaction with electrodes and their behavior under electric fields is a topic of vital significance for these areas, and about which very little is known. Here unprecedented evidence is presented for the controlled peeling of organic molecular material when a voltage is applied between the conducting system and the conducting probe of a scanning force microscope. The rate of removal of the material from the surface of the bulk conducting supramolecular material can be tuned. It depends on the potential applied and is initiated only above a threshold value of 200 mV. The results indicate the importance of electric fields on the stability and performance of conducting organic systems at the nanoscale.  相似文献   
7.
Abstract.  This paper presents the findings of an empirical study investigating the nature of the process of information systems development. These findings are used to identify systems development approach, which extends understanding of the information systems development process beyond the levels of methodology and technical expertise. The term approach expresses the rich, varied, and complex ways in which professionals deal with development situations. The term transcends methodological components – which can be combined, tailored, or omitted altogether. Within approach, a framework for method choice, a key diagnostic scheme, and the use of a central repository reveal the significant background activity that goes into developing information systems. It is suggested that the information systems development process ultimately involves a professional using an approach to intervene in a problematic situation for developing the organization's information and, if needed, other systems. This understanding has implications for examining the field's ineffectiveness in relation to the approach adopted – rather than the methodology used.  相似文献   
8.
A thorough analysis of the water flow and water level control problems arising in several industrial systems is provided using classical and sampled data linear control theory. The analysis is based on simplified linear models of the processes under control. Resulting design rules enable engineers to choose the correct controller both in the continuous-time and in the discrete-time case. A practical application example is included.  相似文献   
9.
Biologically functional Ras isoforms undergo post-translational modifications starting with farnesylation of the most C-terminal cysteine. Combined with further processing steps, this isoprenylation allows for the anchoring of these proteins in endomembranes, where signal transduction events take place. The specific localization is subject to dynamic regulation and assumed to modulate the activity of Ras proteins by governing their spatiotemporal distribution. The delta subunit of phosphodiesterase (PDEdelta) has attracted attention as a solubilization factor of isoprenylated Ras. In this study, we demonstrate that critical residues in the putative isoprenoid pocket of PDEdelta can be mapped by coupling with a semisynthetic N-Ras lipoprotein in which the native farnesyl group of the processed protein was replaced by a photoactivatable geranyl benzophenone moiety. The crosslinked product included parts of beta-sheet 9 of PDEdelta, which contains the highly conserved amino acids V145 and L147. Modeling of the PDEdelta-geranyl benzophenone (GerBP) complex supports the conclusion that the photolabeled sequence is embedded in the putative isoprenoid pocket of PDEdelta.  相似文献   
10.
In this article, we introduce a new general class of nonparametric Shewhart‐type control charts using the lengths of runs of test sample observations between successive observations of a reference sample. Several control charts that have appeared in the literature are members of the new family. In addition, 3 new nonparametric control charts that belong to the class are introduced and studied. Numerical results depict that the proposed charts attain competitive in‐control and out‐of‐control performance as compared with existing nonparametric charts.  相似文献   
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