Sample records for structure alignment program

  1. Iterative refinement of structure-based sequence alignments by Seed Extension

    PubMed Central

    Kim, Changhoon; Tai, Chin-Hsien; Lee, Byungkook

    2009-01-01

    Background Accurate sequence alignment is required in many bioinformatics applications but, when sequence similarity is low, it is difficult to obtain accurate alignments based on sequence similarity alone. The accuracy improves when the structures are available, but current structure-based sequence alignment procedures still mis-align substantial numbers of residues. In order to correct such errors, we previously explored the possibility of replacing the residue-based dynamic programming algorithm in structure alignment procedures with the Seed Extension algorithm, which does not use a gap penalty. Here, we describe a new procedure called RSE (Refinement with Seed Extension) that iteratively refines a structure-based sequence alignment. Results RSE uses SE (Seed Extension) in its core, which is an algorithm that we reported recently for obtaining a sequence alignment from two superimposed structures. The RSE procedure was evaluated by comparing the correctly aligned fractions of residues before and after the refinement of the structure-based sequence alignments produced by popular programs. CE, DaliLite, FAST, LOCK2, MATRAS, MATT, TM-align, SHEBA and VAST were included in this analysis and the NCBI's CDD root node set was used as the reference alignments. RSE improved the average accuracy of sequence alignments for all programs tested when no shift error was allowed. The amount of improvement varied depending on the program. The average improvements were small for DaliLite and MATRAS but about 5% for CE and VAST. More substantial improvements have been seen in many individual cases. The additional computation times required for the refinements were negligible compared to the times taken by the structure alignment programs. Conclusion RSE is a computationally inexpensive way of improving the accuracy of a structure-based sequence alignment. It can be used as a standalone procedure following a regular structure-based sequence alignment or to replace the traditional iterative refinement procedures based on residue-level dynamic programming algorithm in many structure alignment programs. PMID:19589133

  2. StructAlign, a Program for Alignment of Structures of DNA-Protein Complexes.

    PubMed

    Popov, Ya V; Galitsyna, A A; Alexeevski, A V; Karyagina, A S; Spirin, S A

    2015-11-01

    Comparative analysis of structures of complexes of homologous proteins with DNA is important in the analysis of DNA-protein recognition. Alignment is a necessary stage of the analysis. An alignment is a matching of amino acid residues and nucleotides of one complex to residues and nucleotides of the other. Currently, there are no programs available for aligning structures of DNA-protein complexes. We present the program StructAlign, which should fill this gap. The program inputs a pair of complexes of DNA double helix with proteins and outputs an alignment of DNA chains corresponding to the best spatial fit of the protein chains.

  3. Matt: local flexibility aids protein multiple structure alignment.

    PubMed

    Menke, Matthew; Berger, Bonnie; Cowen, Lenore

    2008-01-01

    Even when there is agreement on what measure a protein multiple structure alignment should be optimizing, finding the optimal alignment is computationally prohibitive. One approach used by many previous methods is aligned fragment pair chaining, where short structural fragments from all the proteins are aligned against each other optimally, and the final alignment chains these together in geometrically consistent ways. Ye and Godzik have recently suggested that adding geometric flexibility may help better model protein structures in a variety of contexts. We introduce the program Matt (Multiple Alignment with Translations and Twists), an aligned fragment pair chaining algorithm that, in intermediate steps, allows local flexibility between fragments: small translations and rotations are temporarily allowed to bring sets of aligned fragments closer, even if they are physically impossible under rigid body transformations. After a dynamic programming assembly guided by these "bent" alignments, geometric consistency is restored in the final step before the alignment is output. Matt is tested against other recent multiple protein structure alignment programs on the popular Homstrad and SABmark benchmark datasets. Matt's global performance is competitive with the other programs on Homstrad, but outperforms the other programs on SABmark, a benchmark of multiple structure alignments of proteins with more distant homology. On both datasets, Matt demonstrates an ability to better align the ends of alpha-helices and beta-strands, an important characteristic of any structure alignment program intended to help construct a structural template library for threading approaches to the inverse protein-folding problem. The related question of whether Matt alignments can be used to distinguish distantly homologous structure pairs from pairs of proteins that are not homologous is also considered. For this purpose, a p-value score based on the length of the common core and average root mean squared deviation (RMSD) of Matt alignments is shown to largely separate decoys from homologous protein structures in the SABmark benchmark dataset. We postulate that Matt's strong performance comes from its ability to model proteins in different conformational states and, perhaps even more important, its ability to model backbone distortions in more distantly related proteins.

  4. Structural re-alignment in an immunologic surface region of ricin A chain

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zemla, A T; Zhou, C E

    2007-07-24

    We compared structure alignments generated by several protein structure comparison programs to determine whether existing methods would satisfactorily align residues at a highly conserved position within an immunogenic loop in ribosome inactivating proteins (RIPs). Using default settings, structure alignments generated by several programs (CE, DaliLite, FATCAT, LGA, MAMMOTH, MATRAS, SHEBA, SSM) failed to align the respective conserved residues, although LGA reported correct residue-residue (R-R) correspondences when the beta-carbon (Cb) position was used as the point of reference in the alignment calculations. Further tests using variable points of reference indicated that points distal from the beta carbon along a vector connectingmore » the alpha and beta carbons yielded rigid structural alignments in which residues known to be highly conserved in RIPs were reported as corresponding residues in structural comparisons between ricin A chain, abrin-A, and other RIPs. Results suggest that approaches to structure alignment employing alternate point representations corresponding to side chain position may yield structure alignments that are more consistent with observed conservation of functional surface residues than do standard alignment programs, which apply uniform criteria for alignment (i.e., alpha carbon (Ca) as point of reference) along the entirety of the peptide chain. We present the results of tests that suggest the utility of allowing user-specified points of reference in generating alternate structural alignments, and we present a web server for automatically generating such alignments.« less

  5. Accurate multiple sequence-structure alignment of RNA sequences using combinatorial optimization.

    PubMed

    Bauer, Markus; Klau, Gunnar W; Reinert, Knut

    2007-07-27

    The discovery of functional non-coding RNA sequences has led to an increasing interest in algorithms related to RNA analysis. Traditional sequence alignment algorithms, however, fail at computing reliable alignments of low-homology RNA sequences. The spatial conformation of RNA sequences largely determines their function, and therefore RNA alignment algorithms have to take structural information into account. We present a graph-based representation for sequence-structure alignments, which we model as an integer linear program (ILP). We sketch how we compute an optimal or near-optimal solution to the ILP using methods from combinatorial optimization, and present results on a recently published benchmark set for RNA alignments. The implementation of our algorithm yields better alignments in terms of two published scores than the other programs that we tested: This is especially the case with an increasing number of input sequences. Our program LARA is freely available for academic purposes from http://www.planet-lisa.net.

  6. Representing and comparing protein structures as paths in three-dimensional space

    PubMed Central

    Zhi, Degui; Krishna, S Sri; Cao, Haibo; Pevzner, Pavel; Godzik, Adam

    2006-01-01

    Background Most existing formulations of protein structure comparison are based on detailed atomic level descriptions of protein structures and bypass potential insights that arise from a higher-level abstraction. Results We propose a structure comparison approach based on a simplified representation of proteins that describes its three-dimensional path by local curvature along the generalized backbone of the polypeptide. We have implemented a dynamic programming procedure that aligns curvatures of proteins by optimizing a defined sum turning angle deviation measure. Conclusion Although our procedure does not directly optimize global structural similarity as measured by RMSD, our benchmarking results indicate that it can surprisingly well recover the structural similarity defined by structure classification databases and traditional structure alignment programs. In addition, our program can recognize similarities between structures with extensive conformation changes that are beyond the ability of traditional structure alignment programs. We demonstrate the applications of procedure to several contexts of structure comparison. An implementation of our procedure, CURVE, is available as a public webserver. PMID:17052359

  7. QUASAR--scoring and ranking of sequence-structure alignments.

    PubMed

    Birzele, Fabian; Gewehr, Jan E; Zimmer, Ralf

    2005-12-15

    Sequence-structure alignments are a common means for protein structure prediction in the fields of fold recognition and homology modeling, and there is a broad variety of programs that provide such alignments based on sequence similarity, secondary structure or contact potentials. Nevertheless, finding the best sequence-structure alignment in a pool of alignments remains a difficult problem. QUASAR (quality of sequence-structure alignments ranking) provides a unifying framework for scoring sequence-structure alignments that aids finding well-performing combinations of well-known and custom-made scoring schemes. Those scoring functions can be benchmarked against widely accepted quality scores like MaxSub, TMScore, Touch and APDB, thus enabling users to test their own alignment scores against 'standard-of-truth' structure-based scores. Furthermore, individual score combinations can be optimized with respect to benchmark sets based on known structural relationships using QUASAR's in-built optimization routines.

  8. Implementation of a parallel protein structure alignment service on cloud.

    PubMed

    Hung, Che-Lun; Lin, Yaw-Ling

    2013-01-01

    Protein structure alignment has become an important strategy by which to identify evolutionary relationships between protein sequences. Several alignment tools are currently available for online comparison of protein structures. In this paper, we propose a parallel protein structure alignment service based on the Hadoop distribution framework. This service includes a protein structure alignment algorithm, a refinement algorithm, and a MapReduce programming model. The refinement algorithm refines the result of alignment. To process vast numbers of protein structures in parallel, the alignment and refinement algorithms are implemented using MapReduce. We analyzed and compared the structure alignments produced by different methods using a dataset randomly selected from the PDB database. The experimental results verify that the proposed algorithm refines the resulting alignments more accurately than existing algorithms. Meanwhile, the computational performance of the proposed service is proportional to the number of processors used in our cloud platform.

  9. Implementation of a Parallel Protein Structure Alignment Service on Cloud

    PubMed Central

    Hung, Che-Lun; Lin, Yaw-Ling

    2013-01-01

    Protein structure alignment has become an important strategy by which to identify evolutionary relationships between protein sequences. Several alignment tools are currently available for online comparison of protein structures. In this paper, we propose a parallel protein structure alignment service based on the Hadoop distribution framework. This service includes a protein structure alignment algorithm, a refinement algorithm, and a MapReduce programming model. The refinement algorithm refines the result of alignment. To process vast numbers of protein structures in parallel, the alignment and refinement algorithms are implemented using MapReduce. We analyzed and compared the structure alignments produced by different methods using a dataset randomly selected from the PDB database. The experimental results verify that the proposed algorithm refines the resulting alignments more accurately than existing algorithms. Meanwhile, the computational performance of the proposed service is proportional to the number of processors used in our cloud platform. PMID:23671842

  10. Using structure to explore the sequence alignment space of remote homologs.

    PubMed

    Kuziemko, Andrew; Honig, Barry; Petrey, Donald

    2011-10-01

    Protein structure modeling by homology requires an accurate sequence alignment between the query protein and its structural template. However, sequence alignment methods based on dynamic programming (DP) are typically unable to generate accurate alignments for remote sequence homologs, thus limiting the applicability of modeling methods. A central problem is that the alignment that is "optimal" in terms of the DP score does not necessarily correspond to the alignment that produces the most accurate structural model. That is, the correct alignment based on structural superposition will generally have a lower score than the optimal alignment obtained from sequence. Variations of the DP algorithm have been developed that generate alternative alignments that are "suboptimal" in terms of the DP score, but these still encounter difficulties in detecting the correct structural alignment. We present here a new alternative sequence alignment method that relies heavily on the structure of the template. By initially aligning the query sequence to individual fragments in secondary structure elements and combining high-scoring fragments that pass basic tests for "modelability", we can generate accurate alignments within a small ensemble. Our results suggest that the set of sequences that can currently be modeled by homology can be greatly extended.

  11. 3D flexible alignment using 2D maximum common substructure: dependence of prediction accuracy on target-reference chemical similarity.

    PubMed

    Kawabata, Takeshi; Nakamura, Haruki

    2014-07-28

    A protein-bound conformation of a target molecule can be predicted by aligning the target molecule on the reference molecule obtained from the 3D structure of the compound-protein complex. This strategy is called "similarity-based docking". For this purpose, we develop the flexible alignment program fkcombu, which aligns the target molecule based on atomic correspondences with the reference molecule. The correspondences are obtained by the maximum common substructure (MCS) of 2D chemical structures, using our program kcombu. The prediction performance was evaluated using many target-reference pairs of superimposed ligand 3D structures on the same protein in the PDB, with different ranges of chemical similarity. The details of atomic correspondence largely affected the prediction success. We found that topologically constrained disconnected MCS (TD-MCS) with the simple element-based atomic classification provides the best prediction. The crashing potential energy with the receptor protein improved the performance. We also found that the RMSD between the predicted and correct target conformations significantly correlates with the chemical similarities between target-reference molecules. Generally speaking, if the reference and target compounds have more than 70% chemical similarity, then the average RMSD of 3D conformations is <2.0 Å. We compared the performance with a rigid-body molecular alignment program based on volume-overlap scores (ShaEP). Our MCS-based flexible alignment program performed better than the rigid-body alignment program, especially when the target and reference molecules were sufficiently similar.

  12. gmos: Rapid Detection of Genome Mosaicism over Short Evolutionary Distances.

    PubMed

    Domazet-Lošo, Mirjana; Domazet-Lošo, Tomislav

    2016-01-01

    Prokaryotic and viral genomes are often altered by recombination and horizontal gene transfer. The existing methods for detecting recombination are primarily aimed at viral genomes or sets of loci, since the expensive computation of underlying statistical models often hinders the comparison of complete prokaryotic genomes. As an alternative, alignment-free solutions are more efficient, but cannot map (align) a query to subject genomes. To address this problem, we have developed gmos (Genome MOsaic Structure), a new program that determines the mosaic structure of query genomes when compared to a set of closely related subject genomes. The program first computes local alignments between query and subject genomes and then reconstructs the query mosaic structure by choosing the best local alignment for each query region. To accomplish the analysis quickly, the program mostly relies on pairwise alignments and constructs multiple sequence alignments over short overlapping subject regions only when necessary. This fine-tuned implementation achieves an efficiency comparable to an alignment-free tool. The program performs well for simulated and real data sets of closely related genomes and can be used for fast recombination detection; for instance, when a new prokaryotic pathogen is discovered. As an example, gmos was used to detect genome mosaicism in a pathogenic Enterococcus faecium strain compared to seven closely related genomes. The analysis took less than two minutes on a single 2.1 GHz processor. The output is available in fasta format and can be visualized using an accessory program, gmosDraw (freely available with gmos).

  13. gmos: Rapid Detection of Genome Mosaicism over Short Evolutionary Distances

    PubMed Central

    Domazet-Lošo, Mirjana; Domazet-Lošo, Tomislav

    2016-01-01

    Prokaryotic and viral genomes are often altered by recombination and horizontal gene transfer. The existing methods for detecting recombination are primarily aimed at viral genomes or sets of loci, since the expensive computation of underlying statistical models often hinders the comparison of complete prokaryotic genomes. As an alternative, alignment-free solutions are more efficient, but cannot map (align) a query to subject genomes. To address this problem, we have developed gmos (Genome MOsaic Structure), a new program that determines the mosaic structure of query genomes when compared to a set of closely related subject genomes. The program first computes local alignments between query and subject genomes and then reconstructs the query mosaic structure by choosing the best local alignment for each query region. To accomplish the analysis quickly, the program mostly relies on pairwise alignments and constructs multiple sequence alignments over short overlapping subject regions only when necessary. This fine-tuned implementation achieves an efficiency comparable to an alignment-free tool. The program performs well for simulated and real data sets of closely related genomes and can be used for fast recombination detection; for instance, when a new prokaryotic pathogen is discovered. As an example, gmos was used to detect genome mosaicism in a pathogenic Enterococcus faecium strain compared to seven closely related genomes. The analysis took less than two minutes on a single 2.1 GHz processor. The output is available in fasta format and can be visualized using an accessory program, gmosDraw (freely available with gmos). PMID:27846272

  14. Efficient pairwise RNA structure prediction using probabilistic alignment constraints in Dynalign

    PubMed Central

    2007-01-01

    Background Joint alignment and secondary structure prediction of two RNA sequences can significantly improve the accuracy of the structural predictions. Methods addressing this problem, however, are forced to employ constraints that reduce computation by restricting the alignments and/or structures (i.e. folds) that are permissible. In this paper, a new methodology is presented for the purpose of establishing alignment constraints based on nucleotide alignment and insertion posterior probabilities. Using a hidden Markov model, posterior probabilities of alignment and insertion are computed for all possible pairings of nucleotide positions from the two sequences. These alignment and insertion posterior probabilities are additively combined to obtain probabilities of co-incidence for nucleotide position pairs. A suitable alignment constraint is obtained by thresholding the co-incidence probabilities. The constraint is integrated with Dynalign, a free energy minimization algorithm for joint alignment and secondary structure prediction. The resulting method is benchmarked against the previous version of Dynalign and against other programs for pairwise RNA structure prediction. Results The proposed technique eliminates manual parameter selection in Dynalign and provides significant computational time savings in comparison to prior constraints in Dynalign while simultaneously providing a small improvement in the structural prediction accuracy. Savings are also realized in memory. In experiments over a 5S RNA dataset with average sequence length of approximately 120 nucleotides, the method reduces computation by a factor of 2. The method performs favorably in comparison to other programs for pairwise RNA structure prediction: yielding better accuracy, on average, and requiring significantly lesser computational resources. Conclusion Probabilistic analysis can be utilized in order to automate the determination of alignment constraints for pairwise RNA structure prediction methods in a principled fashion. These constraints can reduce the computational and memory requirements of these methods while maintaining or improving their accuracy of structural prediction. This extends the practical reach of these methods to longer length sequences. The revised Dynalign code is freely available for download. PMID:17445273

  15. Automated eukaryotic gene structure annotation using EVidenceModeler and the Program to Assemble Spliced Alignments

    PubMed Central

    Haas, Brian J; Salzberg, Steven L; Zhu, Wei; Pertea, Mihaela; Allen, Jonathan E; Orvis, Joshua; White, Owen; Buell, C Robin; Wortman, Jennifer R

    2008-01-01

    EVidenceModeler (EVM) is presented as an automated eukaryotic gene structure annotation tool that reports eukaryotic gene structures as a weighted consensus of all available evidence. EVM, when combined with the Program to Assemble Spliced Alignments (PASA), yields a comprehensive, configurable annotation system that predicts protein-coding genes and alternatively spliced isoforms. Our experiments on both rice and human genome sequences demonstrate that EVM produces automated gene structure annotation approaching the quality of manual curation. PMID:18190707

  16. An Accurate Scalable Template-based Alignment Algorithm

    PubMed Central

    Gardner, David P.; Xu, Weijia; Miranker, Daniel P.; Ozer, Stuart; Cannone, Jamie J.; Gutell, Robin R.

    2013-01-01

    The rapid determination of nucleic acid sequences is increasing the number of sequences that are available. Inherent in a template or seed alignment is the culmination of structural and functional constraints that are selecting those mutations that are viable during the evolution of the RNA. While we might not understand these structural and functional, template-based alignment programs utilize the patterns of sequence conservation to encapsulate the characteristics of viable RNA sequences that are aligned properly. We have developed a program that utilizes the different dimensions of information in rCAD, a large RNA informatics resource, to establish a profile for each position in an alignment. The most significant include sequence identity and column composition in different phylogenetic taxa. We have compared our methods with a maximum of eight alternative alignment methods on different sets of 16S and 23S rRNA sequences with sequence percent identities ranging from 50% to 100%. The results showed that CRWAlign outperformed the other alignment methods in both speed and accuracy. A web-based alignment server is available at http://www.rna.ccbb.utexas.edu/SAE/2F/CRWAlign. PMID:24772376

  17. Statistical inference of protein structural alignments using information and compression.

    PubMed

    Collier, James H; Allison, Lloyd; Lesk, Arthur M; Stuckey, Peter J; Garcia de la Banda, Maria; Konagurthu, Arun S

    2017-04-01

    Structural molecular biology depends crucially on computational techniques that compare protein three-dimensional structures and generate structural alignments (the assignment of one-to-one correspondences between subsets of amino acids based on atomic coordinates). Despite its importance, the structural alignment problem has not been formulated, much less solved, in a consistent and reliable way. To overcome these difficulties, we present here a statistical framework for the precise inference of structural alignments, built on the Bayesian and information-theoretic principle of Minimum Message Length (MML). The quality of any alignment is measured by its explanatory power-the amount of lossless compression achieved to explain the protein coordinates using that alignment. We have implemented this approach in MMLigner , the first program able to infer statistically significant structural alignments. We also demonstrate the reliability of MMLigner 's alignment results when compared with the state of the art. Importantly, MMLigner can also discover different structural alignments of comparable quality, a challenging problem for oligomers and protein complexes. Source code, binaries and an interactive web version are available at http://lcb.infotech.monash.edu.au/mmligner . arun.konagurthu@monash.edu. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  18. CAB-Align: A Flexible Protein Structure Alignment Method Based on the Residue-Residue Contact Area.

    PubMed

    Terashi, Genki; Takeda-Shitaka, Mayuko

    2015-01-01

    Proteins are flexible, and this flexibility has an essential functional role. Flexibility can be observed in loop regions, rearrangements between secondary structure elements, and conformational changes between entire domains. However, most protein structure alignment methods treat protein structures as rigid bodies. Thus, these methods fail to identify the equivalences of residue pairs in regions with flexibility. In this study, we considered that the evolutionary relationship between proteins corresponds directly to the residue-residue physical contacts rather than the three-dimensional (3D) coordinates of proteins. Thus, we developed a new protein structure alignment method, contact area-based alignment (CAB-align), which uses the residue-residue contact area to identify regions of similarity. The main purpose of CAB-align is to identify homologous relationships at the residue level between related protein structures. The CAB-align procedure comprises two main steps: First, a rigid-body alignment method based on local and global 3D structure superposition is employed to generate a sufficient number of initial alignments. Then, iterative dynamic programming is executed to find the optimal alignment. We evaluated the performance and advantages of CAB-align based on four main points: (1) agreement with the gold standard alignment, (2) alignment quality based on an evolutionary relationship without 3D coordinate superposition, (3) consistency of the multiple alignments, and (4) classification agreement with the gold standard classification. Comparisons of CAB-align with other state-of-the-art protein structure alignment methods (TM-align, FATCAT, and DaliLite) using our benchmark dataset showed that CAB-align performed robustly in obtaining high-quality alignments and generating consistent multiple alignments with high coverage and accuracy rates, and it performed extremely well when discriminating between homologous and nonhomologous pairs of proteins in both single and multi-domain comparisons. The CAB-align software is freely available to academic users as stand-alone software at http://www.pharm.kitasato-u.ac.jp/bmd/bmd/Publications.html.

  19. PARTS: Probabilistic Alignment for RNA joinT Secondary structure prediction

    PubMed Central

    Harmanci, Arif Ozgun; Sharma, Gaurav; Mathews, David H.

    2008-01-01

    A novel method is presented for joint prediction of alignment and common secondary structures of two RNA sequences. The joint consideration of common secondary structures and alignment is accomplished by structural alignment over a search space defined by the newly introduced motif called matched helical regions. The matched helical region formulation generalizes previously employed constraints for structural alignment and thereby better accommodates the structural variability within RNA families. A probabilistic model based on pseudo free energies obtained from precomputed base pairing and alignment probabilities is utilized for scoring structural alignments. Maximum a posteriori (MAP) common secondary structures, sequence alignment and joint posterior probabilities of base pairing are obtained from the model via a dynamic programming algorithm called PARTS. The advantage of the more general structural alignment of PARTS is seen in secondary structure predictions for the RNase P family. For this family, the PARTS MAP predictions of secondary structures and alignment perform significantly better than prior methods that utilize a more restrictive structural alignment model. For the tRNA and 5S rRNA families, the richer structural alignment model of PARTS does not offer a benefit and the method therefore performs comparably with existing alternatives. For all RNA families studied, the posterior probability estimates obtained from PARTS offer an improvement over posterior probability estimates from a single sequence prediction. When considering the base pairings predicted over a threshold value of confidence, the combination of sensitivity and positive predictive value is superior for PARTS than for the single sequence prediction. PARTS source code is available for download under the GNU public license at http://rna.urmc.rochester.edu. PMID:18304945

  20. KISS for STRAP: user extensions for a protein alignment editor.

    PubMed

    Gille, Christoph; Lorenzen, Stephan; Michalsky, Elke; Frömmel, Cornelius

    2003-12-12

    The Structural Alignment Program STRAP is a comfortable comprehensive editor and analyzing tool for protein alignments. A wide range of functions related to protein sequences and protein structures are accessible with an intuitive graphical interface. Recent features include mapping of mutations and polymorphisms onto structures and production of high quality figures for publication. Here we address the general problem of multi-purpose program packages to keep up with the rapid development of bioinformatical methods and the demand for specific program functions. STRAP was remade implementing a novel design which aims at Keeping Interfaces in STRAP Simple (KISS). KISS renders STRAP extendable to bio-scientists as well as to bio-informaticians. Scientists with basic computer skills are capable of implementing statistical methods or embedding existing bioinformatical tools in STRAP themselves. For bio-informaticians STRAP may serve as an environment for rapid prototyping and testing of complex algorithms such as automatic alignment algorithms or phylogenetic methods. Further, STRAP can be applied as an interactive web applet to present data related to a particular protein family and as a teaching tool. JAVA-1.4 or higher. http://www.charite.de/bioinf/strap/

  1. A new statistical framework to assess structural alignment quality using information compression

    PubMed Central

    Collier, James H.; Allison, Lloyd; Lesk, Arthur M.; Garcia de la Banda, Maria; Konagurthu, Arun S.

    2014-01-01

    Motivation: Progress in protein biology depends on the reliability of results from a handful of computational techniques, structural alignments being one. Recent reviews have highlighted substantial inconsistencies and differences between alignment results generated by the ever-growing stock of structural alignment programs. The lack of consensus on how the quality of structural alignments must be assessed has been identified as the main cause for the observed differences. Current methods assess structural alignment quality by constructing a scoring function that attempts to balance conflicting criteria, mainly alignment coverage and fidelity of structures under superposition. This traditional approach to measuring alignment quality, the subject of considerable literature, has failed to solve the problem. Further development along the same lines is unlikely to rectify the current deficiencies in the field. Results: This paper proposes a new statistical framework to assess structural alignment quality and significance based on lossless information compression. This is a radical departure from the traditional approach of formulating scoring functions. It links the structural alignment problem to the general class of statistical inductive inference problems, solved using the information-theoretic criterion of minimum message length. Based on this, we developed an efficient and reliable measure of structural alignment quality, I-value. The performance of I-value is demonstrated in comparison with a number of popular scoring functions, on a large collection of competing alignments. Our analysis shows that I-value provides a rigorous and reliable quantification of structural alignment quality, addressing a major gap in the field. Availability: http://lcb.infotech.monash.edu.au/I-value Contact: arun.konagurthu@monash.edu Supplementary information: Online supplementary data are available at http://lcb.infotech.monash.edu.au/I-value/suppl.html PMID:25161241

  2. Dinucleotide controlled null models for comparative RNA gene prediction.

    PubMed

    Gesell, Tanja; Washietl, Stefan

    2008-05-27

    Comparative prediction of RNA structures can be used to identify functional noncoding RNAs in genomic screens. It was shown recently by Babak et al. [BMC Bioinformatics. 8:33] that RNA gene prediction programs can be biased by the genomic dinucleotide content, in particular those programs using a thermodynamic folding model including stacking energies. As a consequence, there is need for dinucleotide-preserving control strategies to assess the significance of such predictions. While there have been randomization algorithms for single sequences for many years, the problem has remained challenging for multiple alignments and there is currently no algorithm available. We present a program called SISSIz that simulates multiple alignments of a given average dinucleotide content. Meeting additional requirements of an accurate null model, the randomized alignments are on average of the same sequence diversity and preserve local conservation and gap patterns. We make use of a phylogenetic substitution model that includes overlapping dependencies and site-specific rates. Using fast heuristics and a distance based approach, a tree is estimated under this model which is used to guide the simulations. The new algorithm is tested on vertebrate genomic alignments and the effect on RNA structure predictions is studied. In addition, we directly combined the new null model with the RNAalifold consensus folding algorithm giving a new variant of a thermodynamic structure based RNA gene finding program that is not biased by the dinucleotide content. SISSIz implements an efficient algorithm to randomize multiple alignments preserving dinucleotide content. It can be used to get more accurate estimates of false positive rates of existing programs, to produce negative controls for the training of machine learning based programs, or as standalone RNA gene finding program. Other applications in comparative genomics that require randomization of multiple alignments can be considered. SISSIz is available as open source C code that can be compiled for every major platform and downloaded here: http://sourceforge.net/projects/sissiz.

  3. Accelerated probabilistic inference of RNA structure evolution

    PubMed Central

    Holmes, Ian

    2005-01-01

    Background Pairwise stochastic context-free grammars (Pair SCFGs) are powerful tools for evolutionary analysis of RNA, including simultaneous RNA sequence alignment and secondary structure prediction, but the associated algorithms are intensive in both CPU and memory usage. The same problem is faced by other RNA alignment-and-folding algorithms based on Sankoff's 1985 algorithm. It is therefore desirable to constrain such algorithms, by pre-processing the sequences and using this first pass to limit the range of structures and/or alignments that can be considered. Results We demonstrate how flexible classes of constraint can be imposed, greatly reducing the computational costs while maintaining a high quality of structural homology prediction. Any score-attributed context-free grammar (e.g. energy-based scoring schemes, or conditionally normalized Pair SCFGs) is amenable to this treatment. It is now possible to combine independent structural and alignment constraints of unprecedented general flexibility in Pair SCFG alignment algorithms. We outline several applications to the bioinformatics of RNA sequence and structure, including Waterman-Eggert N-best alignments and progressive multiple alignment. We evaluate the performance of the algorithm on test examples from the RFAM database. Conclusion A program, Stemloc, that implements these algorithms for efficient RNA sequence alignment and structure prediction is available under the GNU General Public License. PMID:15790387

  4. A novel approach to multiple sequence alignment using hadoop data grids.

    PubMed

    Sudha Sadasivam, G; Baktavatchalam, G

    2010-01-01

    Multiple alignment of protein sequences helps to determine evolutionary linkage and to predict molecular structures. The factors to be considered while aligning multiple sequences are speed and accuracy of alignment. Although dynamic programming algorithms produce accurate alignments, they are computation intensive. In this paper we propose a time efficient approach to sequence alignment that also produces quality alignment. The dynamic nature of the algorithm coupled with data and computational parallelism of hadoop data grids improves the accuracy and speed of sequence alignment. The principle of block splitting in hadoop coupled with its scalability facilitates alignment of very large sequences.

  5. LS-align: an atom-level, flexible ligand structural alignment algorithm for high-throughput virtual screening.

    PubMed

    Hu, Jun; Liu, Zi; Yu, Dong-Jun; Zhang, Yang

    2018-02-15

    Sequence-order independent structural comparison, also called structural alignment, of small ligand molecules is often needed for computer-aided virtual drug screening. Although many ligand structure alignment programs are proposed, most of them build the alignments based on rigid-body shape comparison which cannot provide atom-specific alignment information nor allow structural variation; both abilities are critical to efficient high-throughput virtual screening. We propose a novel ligand comparison algorithm, LS-align, to generate fast and accurate atom-level structural alignments of ligand molecules, through an iterative heuristic search of the target function that combines inter-atom distance with mass and chemical bond comparisons. LS-align contains two modules of Rigid-LS-align and Flexi-LS-align, designed for rigid-body and flexible alignments, respectively, where a ligand-size independent, statistics-based scoring function is developed to evaluate the similarity of ligand molecules relative to random ligand pairs. Large-scale benchmark tests are performed on prioritizing chemical ligands of 102 protein targets involving 1,415,871 candidate compounds from the DUD-E (Database of Useful Decoys: Enhanced) database, where LS-align achieves an average enrichment factor (EF) of 22.0 at the 1% cutoff and the AUC score of 0.75, which are significantly higher than other state-of-the-art methods. Detailed data analyses show that the advanced performance is mainly attributed to the design of the target function that combines structural and chemical information to enhance the sensitivity of recognizing subtle difference of ligand molecules and the introduces of structural flexibility that help capture the conformational changes induced by the ligand-receptor binding interactions. These data demonstrate a new avenue to improve the virtual screening efficiency through the development of sensitive ligand structural alignments. http://zhanglab.ccmb.med.umich.edu/LS-align/. njyudj@njust.edu.cn or zhng@umich.edu. Supplementary data are available at Bioinformatics online.

  6. GenomeVista

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poliakov, Alexander; Couronne, Olivier

    2002-11-04

    Aligning large vertebrate genomes that are structurally complex poses a variety of problems not encountered on smaller scales. Such genomes are rich in repetitive elements and contain multiple segmental duplications, which increases the difficulty of identifying true orthologous SNA segments in alignments. The sizes of the sequences make many alignment algorithms designed for comparing single proteins extremely inefficient when processing large genomic intervals. We integrated both local and global alignment tools and developed a suite of programs for automatically aligning large vertebrate genomes and identifying conserved non-coding regions in the alignments. Our method uses the BLAT local alignment program tomore » find anchors on the base genome to identify regions of possible homology for a query sequence. These regions are postprocessed to find the best candidates which are then globally aligned using the AVID global alignment program. In the last step conserved non-coding segments are identified using VISTA. Our methods are fast and the resulting alignments exhibit a high degree of sensitivity, covering more than 90% of known coding exons in the human genome. The GenomeVISTA software is a suite of Perl programs that is built on a MySQL database platform. The scheduler gets control data from the database, builds a queve of jobs, and dispatches them to a PC cluster for execution. The main program, running on each node of the cluster, processes individual sequences. A Perl library acts as an interface between the database and the above programs. The use of a separate library allows the programs to function independently of the database schema. The library also improves on the standard Perl MySQL database interfere package by providing auto-reconnect functionality and improved error handling.« less

  7. Evaluation of sequence alignments and oligonucleotide probes with respect to three-dimensional structure of ribosomal RNA using ARB software package

    PubMed Central

    Kumar, Yadhu; Westram, Ralf; Kipfer, Peter; Meier, Harald; Ludwig, Wolfgang

    2006-01-01

    Background Availability of high-resolution RNA crystal structures for the 30S and 50S ribosomal subunits and the subsequent validation of comparative secondary structure models have prompted the biologists to use three-dimensional structure of ribosomal RNA (rRNA) for evaluating sequence alignments of rRNA genes. Furthermore, the secondary and tertiary structural features of rRNA are highly useful and successfully employed in designing rRNA targeted oligonucleotide probes intended for in situ hybridization experiments. RNA3D, a program to combine sequence alignment information with three-dimensional structure of rRNA was developed. Integration into ARB software package, which is used extensively by the scientific community for phylogenetic analysis and molecular probe designing, has substantially extended the functionality of ARB software suite with 3D environment. Results Three-dimensional structure of rRNA is visualized in OpenGL 3D environment with the abilities to change the display and overlay information onto the molecule, dynamically. Phylogenetic information derived from the multiple sequence alignments can be overlaid onto the molecule structure in a real time. Superimposition of both statistical and non-statistical sequence associated information onto the rRNA 3D structure can be done using customizable color scheme, which is also applied to a textual sequence alignment for reference. Oligonucleotide probes designed by ARB probe design tools can be mapped onto the 3D structure along with the probe accessibility models for evaluation with respect to secondary and tertiary structural conformations of rRNA. Conclusion Visualization of three-dimensional structure of rRNA in an intuitive display provides the biologists with the greater possibilities to carry out structure based phylogenetic analysis. Coupled with secondary structure models of rRNA, RNA3D program aids in validating the sequence alignments of rRNA genes and evaluating probe target sites. Superimposition of the information derived from the multiple sequence alignment onto the molecule dynamically allows the researchers to observe any sequence inherited characteristics (phylogenetic information) in real-time environment. The extended ARB software package is made freely available for the scientific community via . PMID:16672074

  8. Using Variable-Length Aligned Fragment Pairs and an Improved Transition Function for Flexible Protein Structure Alignment.

    PubMed

    Cao, Hu; Lu, Yonggang

    2017-01-01

    With the rapid growth of known protein 3D structures in number, how to efficiently compare protein structures becomes an essential and challenging problem in computational structural biology. At present, many protein structure alignment methods have been developed. Among all these methods, flexible structure alignment methods are shown to be superior to rigid structure alignment methods in identifying structure similarities between proteins, which have gone through conformational changes. It is also found that the methods based on aligned fragment pairs (AFPs) have a special advantage over other approaches in balancing global structure similarities and local structure similarities. Accordingly, we propose a new flexible protein structure alignment method based on variable-length AFPs. Compared with other methods, the proposed method possesses three main advantages. First, it is based on variable-length AFPs. The length of each AFP is separately determined to maximally represent a local similar structure fragment, which reduces the number of AFPs. Second, it uses local coordinate systems, which simplify the computation at each step of the expansion of AFPs during the AFP identification. Third, it decreases the number of twists by rewarding the situation where nonconsecutive AFPs share the same transformation in the alignment, which is realized by dynamic programming with an improved transition function. The experimental data show that compared with FlexProt, FATCAT, and FlexSnap, the proposed method can achieve comparable results by introducing fewer twists. Meanwhile, it can generate results similar to those of the FATCAT method in much less running time due to the reduced number of AFPs.

  9. CAS-ATLID (co-alignment sensor of ATLID instrument) thermo-structural design and performance

    NASA Astrophysics Data System (ADS)

    Moreno, Javier; Serrano, Javier; González, David; Rodríguez, Gemma; Manjón, Andrés.; Vásquez, Eloi; Carretero, Carlos; Martínez, Berta

    2017-11-01

    This paper describes the main thermo-mechanical design features and performances of the Co-Alignment Sensor (CAS) developed by LIDAX and CRISA under ESA program with AIRBUS Defence and Space as industry prime.

  10. Robust prediction of consensus secondary structures using averaged base pairing probability matrices.

    PubMed

    Kiryu, Hisanori; Kin, Taishin; Asai, Kiyoshi

    2007-02-15

    Recent transcriptomic studies have revealed the existence of a considerable number of non-protein-coding RNA transcripts in higher eukaryotic cells. To investigate the functional roles of these transcripts, it is of great interest to find conserved secondary structures from multiple alignments on a genomic scale. Since multiple alignments are often created using alignment programs that neglect the special conservation patterns of RNA secondary structures for computational efficiency, alignment failures can cause potential risks of overlooking conserved stem structures. We investigated the dependence of the accuracy of secondary structure prediction on the quality of alignments. We compared three algorithms that maximize the expected accuracy of secondary structures as well as other frequently used algorithms. We found that one of our algorithms, called McCaskill-MEA, was more robust against alignment failures than others. The McCaskill-MEA method first computes the base pairing probability matrices for all the sequences in the alignment and then obtains the base pairing probability matrix of the alignment by averaging over these matrices. The consensus secondary structure is predicted from this matrix such that the expected accuracy of the prediction is maximized. We show that the McCaskill-MEA method performs better than other methods, particularly when the alignment quality is low and when the alignment consists of many sequences. Our model has a parameter that controls the sensitivity and specificity of predictions. We discussed the uses of that parameter for multi-step screening procedures to search for conserved secondary structures and for assigning confidence values to the predicted base pairs. The C++ source code that implements the McCaskill-MEA algorithm and the test dataset used in this paper are available at http://www.ncrna.org/papers/McCaskillMEA/. Supplementary data are available at Bioinformatics online.

  11. Hidden Markov models-based system (HMMSPECTR) for detecting structural homologies on the basis of sequential information.

    PubMed

    Tsigelny, Igor; Sharikov, Yuriy; Ten Eyck, Lynn F

    2002-05-01

    HMMSPECTR is a tool for finding putative structural homologs for proteins with known primary sequences. HMMSPECTR contains four major components: a data warehouse with the hidden Markov models (HMM) and alignment libraries; a search program which compares the initial protein sequences with the libraries of HMMs; a secondary structure prediction and comparison program; and a dominant protein selection program that prepares the set of 10-15 "best" proteins from the chosen HMMs. The data warehouse contains four libraries of HMMs. The first two libraries were constructed using different HHM preparation options of the HAMMER program. The third library contains parts ("partial HMM") of initial alignments. The fourth library contains trained HMMs. We tested our program against all of the protein targets proposed in the CASP4 competition. The data warehouse included libraries of structural alignments and HMMs constructed on the basis of proteins publicly available in the Protein Data Bank before the CASP4 meeting. The newest fully automated versions of HMMSPECTR 1.02 and 1.02ss produced better results than the best result reported at CASP4 either by r.m.s.d. or by length (or both) in 64% (HMMSPECTR 1.02) and 79% (HMMSPECTR 1.02ss) of the cases. The improvement is most notable for the targets with complexity 4 (difficult fold recognition cases).

  12. Automated insertion of sequences into a ribosomal RNA alignment: An application of computational linguistics in molecular biology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, R.C.

    This thesis involved the construction of (1) a grammar that incorporates knowledge on base invariancy and secondary structure in a molecule and (2) a parser engine that uses the grammar to position bases into the structural subunits of the molecule. These concepts were combined with a novel pinning technique to form a tool that semi-automates insertion of a new species into the alignment for the 16S rRNA molecule (a component of the ribosome) maintained by Dr. Carl Woese's group at the University of Illinois at Urbana. The tool was tested on species extracted from the alignment and on a groupmore » of entirely new species. The results were very encouraging, and the tool should be substantial aid to the curators of the 16S alignment. The construction of the grammar was itself automated, allowing application of the tool to alignments for other molecules. The logic programming language Prolog was used to construct all programs involved. The computational linguistics approach used here was found to be a useful way to attach the problem of insertion into an alignment.« less

  13. Automated insertion of sequences into a ribosomal RNA alignment: An application of computational linguistics in molecular biology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, Ronald C.

    This thesis involved the construction of (1) a grammar that incorporates knowledge on base invariancy and secondary structure in a molecule and (2) a parser engine that uses the grammar to position bases into the structural subunits of the molecule. These concepts were combined with a novel pinning technique to form a tool that semi-automates insertion of a new species into the alignment for the 16S rRNA molecule (a component of the ribosome) maintained by Dr. Carl Woese`s group at the University of Illinois at Urbana. The tool was tested on species extracted from the alignment and on a groupmore » of entirely new species. The results were very encouraging, and the tool should be substantial aid to the curators of the 16S alignment. The construction of the grammar was itself automated, allowing application of the tool to alignments for other molecules. The logic programming language Prolog was used to construct all programs involved. The computational linguistics approach used here was found to be a useful way to attach the problem of insertion into an alignment.« less

  14. GOSSIP: a method for fast and accurate global alignment of protein structures.

    PubMed

    Kifer, I; Nussinov, R; Wolfson, H J

    2011-04-01

    The database of known protein structures (PDB) is increasing rapidly. This results in a growing need for methods that can cope with the vast amount of structural data. To analyze the accumulating data, it is important to have a fast tool for identifying similar structures and clustering them by structural resemblance. Several excellent tools have been developed for the comparison of protein structures. These usually address the task of local structure alignment, an important yet computationally intensive problem due to its complexity. It is difficult to use such tools for comparing a large number of structures to each other at a reasonable time. Here we present GOSSIP, a novel method for a global all-against-all alignment of any set of protein structures. The method detects similarities between structures down to a certain cutoff (a parameter of the program), hence allowing it to detect similar structures at a much higher speed than local structure alignment methods. GOSSIP compares many structures in times which are several orders of magnitude faster than well-known available structure alignment servers, and it is also faster than a database scanning method. We evaluate GOSSIP both on a dataset of short structural fragments and on two large sequence-diverse structural benchmarks. Our conclusions are that for a threshold of 0.6 and above, the speed of GOSSIP is obtained with no compromise of the accuracy of the alignments or of the number of detected global similarities. A server, as well as an executable for download, are available at http://bioinfo3d.cs.tau.ac.il/gossip/.

  15. Evolution of physician-hospital alignment models: a case study of comanagement.

    PubMed

    Sowers, Kevin W; Newman, Paul R; Langdon, Jeffrey C

    2013-06-01

    Recently, quality, financial, and regulatory demands have driven physicians to seek alignment opportunities with hospitals. The motivation for alignment on the part of physicians and hospitals is now accelerating because the new paradigm under healthcare reform requires an increased focus on improving quality, cost, and efficiency. We (1) identify the key drivers for physician-hospital alignment models; (2) summarize comanagement as a physician-hospital alignment model; and (3) explore a detailed case study of comanagement as an option to better align physicians with hospital goals on quality, safety, and outcomes. A Medline abstract review was performed that identified 45 references that discuss options for physician-hospital alignment. None of the articles identified provide a detailed example of successful alignment structures. A detailed case study of a successful comanagement alignment program is reviewed. The key drivers for alignment are inpatient growth rates, declining reimbursements, and the opportunity to improve quality, decrease costs, and increase efficiency. Two general strategies of alignment involve noneconomic and/or economic integration. In our example, comanagement with economic integration was chosen as the preferred structure for physician-hospital alignment. The choice of structure will vary depending on the existing relationships and governance of the hospital and the physicians in the targeted area of focus. The measure of success in building physician-hospital alignment is measured in improvements in care for the patient, reduced cost of care delivery, and improved relations between physicians and hospital leadership.

  16. JDet: interactive calculation and visualization of function-related conservation patterns in multiple sequence alignments and structures.

    PubMed

    Muth, Thilo; García-Martín, Juan A; Rausell, Antonio; Juan, David; Valencia, Alfonso; Pazos, Florencio

    2012-02-15

    We have implemented in a single package all the features required for extracting, visualizing and manipulating fully conserved positions as well as those with a family-dependent conservation pattern in multiple sequence alignments. The program allows, among other things, to run different methods for extracting these positions, combine the results and visualize them in protein 3D structures and sequence spaces. JDet is a multiplatform application written in Java. It is freely available, including the source code, at http://csbg.cnb.csic.es/JDet. The package includes two of our recently developed programs for detecting functional positions in protein alignments (Xdet and S3Det), and support for other methods can be added as plug-ins. A help file and a guided tutorial for JDet are also available.

  17. Aligning K-12 and Postsecondary Career Pathways with Workforce Needs

    ERIC Educational Resources Information Center

    Zinth, Jennifer

    2015-01-01

    Since 2013, states have witnessed significant legislative activity related to secondary- and postsecondary-level career/technical education (CTE). One key goal of much recent policymaking activity has been to improve alignment between high school and postsecondary CTE programs, including by developing state or regional structures to design career…

  18. MetalS2: a tool for the structural alignment of minimal functional sites in metal-binding proteins and nucleic acids.

    PubMed

    Andreini, Claudia; Cavallaro, Gabriele; Rosato, Antonio; Valasatava, Yana

    2013-11-25

    We developed a new software tool, MetalS(2), for the structural alignment of Minimal Functional Sites (MFSs) in metal-binding biological macromolecules. MFSs are 3D templates that describe the local environment around the metal(s) independently of the larger context of the macromolecular structure. Such local environment has a determinant role in tuning the chemical reactivity of the metal, ultimately contributing to the functional properties of the whole system. On our example data sets, MetalS(2) unveiled structural similarities that other programs for protein structure comparison do not consistently point out and overall identified a larger number of structurally similar MFSs. MetalS(2) supports the comparison of MFSs harboring different metals and/or with different nuclearity and is available both as a stand-alone program and a Web tool ( http://metalweb.cerm.unifi.it/tools/metals2/).

  19. Characterising RNA secondary structure space using information entropy

    PubMed Central

    2013-01-01

    Comparative methods for RNA secondary structure prediction use evolutionary information from RNA alignments to increase prediction accuracy. The model is often described in terms of stochastic context-free grammars (SCFGs), which generate a probability distribution over secondary structures. It is, however, unclear how this probability distribution changes as a function of the input alignment. As prediction programs typically only return a single secondary structure, better characterisation of the underlying probability space of RNA secondary structures is of great interest. In this work, we show how to efficiently compute the information entropy of the probability distribution over RNA secondary structures produced for RNA alignments by a phylo-SCFG, and implement it for the PPfold model. We also discuss interpretations and applications of this quantity, including how it can clarify reasons for low prediction reliability scores. PPfold and its source code are available from http://birc.au.dk/software/ppfold/. PMID:23368905

  20. A Novel Partial Sequence Alignment Tool for Finding Large Deletions

    PubMed Central

    Aruk, Taner; Ustek, Duran; Kursun, Olcay

    2012-01-01

    Finding large deletions in genome sequences has become increasingly more useful in bioinformatics, such as in clinical research and diagnosis. Although there are a number of publically available next generation sequencing mapping and sequence alignment programs, these software packages do not correctly align fragments containing deletions larger than one kb. We present a fast alignment software package, BinaryPartialAlign, that can be used by wet lab scientists to find long structural variations in their experiments. For BinaryPartialAlign, we make use of the Smith-Waterman (SW) algorithm with a binary-search-based approach for alignment with large gaps that we called partial alignment. BinaryPartialAlign implementation is compared with other straight-forward applications of SW. Simulation results on mtDNA fragments demonstrate the effectiveness (runtime and accuracy) of the proposed method. PMID:22566777

  1. Exact calculation of distributions on integers, with application to sequence alignment.

    PubMed

    Newberg, Lee A; Lawrence, Charles E

    2009-01-01

    Computational biology is replete with high-dimensional discrete prediction and inference problems. Dynamic programming recursions can be applied to several of the most important of these, including sequence alignment, RNA secondary-structure prediction, phylogenetic inference, and motif finding. In these problems, attention is frequently focused on some scalar quantity of interest, a score, such as an alignment score or the free energy of an RNA secondary structure. In many cases, score is naturally defined on integers, such as a count of the number of pairing differences between two sequence alignments, or else an integer score has been adopted for computational reasons, such as in the test of significance of motif scores. The probability distribution of the score under an appropriate probabilistic model is of interest, such as in tests of significance of motif scores, or in calculation of Bayesian confidence limits around an alignment. Here we present three algorithms for calculating the exact distribution of a score of this type; then, in the context of pairwise local sequence alignments, we apply the approach so as to find the alignment score distribution and Bayesian confidence limits.

  2. Alliance for NanoHealth Competitive Research Program

    DTIC Science & Technology

    2009-10-28

    25-35 Guided Microvasculature Formation and Cellular Infiltration for Tissue Regeneration Applications in Nano-Structured Silk ...V, Davis G, Gordon A, Altman A, Reece G, Gascoyne P, Mathur AB, Endothelial and Stem Cell Interactions on Dielectrophoretically Aligned Fibrous Silk ...Interactions on Dielectrophoretically Aligned Fibrous Silk Fibroin-­‐Chitosan Scaffolds, Journal of Biomedical Materials Research, Accepted October

  3. Transplant programs, centers, and institutes: what does it all mean?

    PubMed

    Abouljoud, Marwan; Whitehouse, Sarah

    2013-04-01

    There are more than 250 transplant centers in the USA, but variation continues to exist in organizational structure for transplant multidisciplinary services. We reviewed the literature to explore the definitions for transplant organizational structures and address existing rationale for the development of the integrated transplant service line. No standard definitions exist to differentiate the use of program, center, institute, or service line. A survey of 20 multiorgan transplant centers in the USA showed that most were named centers or institutes, but some were organized as departments and service lines. The prevailing themes were the perceived need for autonomy of the transplant entity, alignment among services and finances, and the alignment of authority with responsibility. In addition, perceived benefits included growth, alignment, efficiency, and resource allocation. The multidisciplinary nature of transplantation generally has been fit into the matrix organizational model, although many hospitals today have departments, centers, institutes, and service lines structures. Integration has been viewed as beneficial by most transplant entities reviewed, with a sense that it is better adapted for the evolving healthcare climate.

  4. The Implementation of a Structured Nursing Leadership Development Program for Succession Planning in a Health System.

    PubMed

    Ramseur, Priscilla; Fuchs, Mary Ann; Edwards, Pamela; Humphreys, Janice

    2018-01-01

    Preparing future nursing leaders to be successful is important because many current leaders will retire in large numbers in the future. A structured nursing leadership development program utilizing the Essentials of Nurse Manager Orientation online program provided future nursing leaders with content aligned with nursing leadership competencies. Paired with assigned mentors and monthly leadership sessions, the participants increased their perception of leadership competence.

  5. Are Elementary Teacher Education Programs the Real Problem of Unqualified Teachers?

    ERIC Educational Resources Information Center

    Weitman, Catheryn J.; Colbert, Ronald P.

    This paper describes 10 factors that impact misguided perceptions of teacher preparation and teacher quality, especially elementary teachers prepared in highly-structured, university-based teacher preparation programs: (1) the offshoot of P-12 preparation, prior to attending postsecondary programs; (2) alignment of certification tests to state…

  6. Rapid detection, classification and accurate alignment of up to a million or more related protein sequences.

    PubMed

    Neuwald, Andrew F

    2009-08-01

    The patterns of sequence similarity and divergence present within functionally diverse, evolutionarily related proteins contain implicit information about corresponding biochemical similarities and differences. A first step toward accessing such information is to statistically analyze these patterns, which, in turn, requires that one first identify and accurately align a very large set of protein sequences. Ideally, the set should include many distantly related, functionally divergent subgroups. Because it is extremely difficult, if not impossible for fully automated methods to align such sequences correctly, researchers often resort to manual curation based on detailed structural and biochemical information. However, multiply-aligning vast numbers of sequences in this way is clearly impractical. This problem is addressed using Multiply-Aligned Profiles for Global Alignment of Protein Sequences (MAPGAPS). The MAPGAPS program uses a set of multiply-aligned profiles both as a query to detect and classify related sequences and as a template to multiply-align the sequences. It relies on Karlin-Altschul statistics for sensitivity and on PSI-BLAST (and other) heuristics for speed. Using as input a carefully curated multiple-profile alignment for P-loop GTPases, MAPGAPS correctly aligned weakly conserved sequence motifs within 33 distantly related GTPases of known structure. By comparison, the sequence- and structurally based alignment methods hmmalign and PROMALS3D misaligned at least 11 and 23 of these regions, respectively. When applied to a dataset of 65 million protein sequences, MAPGAPS identified, classified and aligned (with comparable accuracy) nearly half a million putative P-loop GTPase sequences. A C++ implementation of MAPGAPS is available at http://mapgaps.igs.umaryland.edu. Supplementary data are available at Bioinformatics online.

  7. Pairagon: a highly accurate, HMM-based cDNA-to-genome aligner.

    PubMed

    Lu, David V; Brown, Randall H; Arumugam, Manimozhiyan; Brent, Michael R

    2009-07-01

    The most accurate way to determine the intron-exon structures in a genome is to align spliced cDNA sequences to the genome. Thus, cDNA-to-genome alignment programs are a key component of most annotation pipelines. The scoring system used to choose the best alignment is a primary determinant of alignment accuracy, while heuristics that prevent consideration of certain alignments are a primary determinant of runtime and memory usage. Both accuracy and speed are important considerations in choosing an alignment algorithm, but scoring systems have received much less attention than heuristics. We present Pairagon, a pair hidden Markov model based cDNA-to-genome alignment program, as the most accurate aligner for sequences with high- and low-identity levels. We conducted a series of experiments testing alignment accuracy with varying sequence identity. We first created 'perfect' simulated cDNA sequences by splicing the sequences of exons in the reference genome sequences of fly and human. The complete reference genome sequences were then mutated to various degrees using a realistic mutation simulator and the perfect cDNAs were aligned to them using Pairagon and 12 other aligners. To validate these results with natural sequences, we performed cross-species alignment using orthologous transcripts from human, mouse and rat. We found that aligner accuracy is heavily dependent on sequence identity. For sequences with 100% identity, Pairagon achieved accuracy levels of >99.6%, with one quarter of the errors of any other aligner. Furthermore, for human/mouse alignments, which are only 85% identical, Pairagon achieved 87% accuracy, higher than any other aligner. Pairagon source and executables are freely available at http://mblab.wustl.edu/software/pairagon/

  8. Comparative Protein Structure Modeling Using MODELLER

    PubMed Central

    Webb, Benjamin; Sali, Andrej

    2016-01-01

    Comparative protein structure modeling predicts the three-dimensional structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and how to use the ModBase database of such models, and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. PMID:27322406

  9. Structural phylogeny by profile extraction and multiple superimposition using electrostatic congruence as a discriminator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chakraborty, Sandeep; Rao, Basuthkar J.; Baker, Nathan A.

    2013-04-01

    Phylogenetic analysis of proteins using multiple sequence alignment (MSA) assumes an underlying evolutionary relationship in these proteins which occasionally remains undetected due to considerable sequence divergence. Structural alignment programs have been developed to unravel such fuzzy relationships. However, none of these structure based methods have used electrostatic properties to discriminate between spatially equivalent residues. We present a methodology for MSA of a set of related proteins with known structures using electrostatic properties as an additional discriminator (STEEP). STEEP first extracts a profile, then generates a multiple structural superimposition providing a consolidated spatial framework for comparing residues and finally emits themore » MSA. Residues that are aligned differently by including or excluding electrostatic properties can be targeted by directed evolution experiments to transform the enzymatic properties of one protein into another. We have compared STEEP results to those obtained from a MSA program (ClustalW) and a structural alignment method (MUSTANG) for chymotrypsin serine proteases. Subsequently, we used PhyML to generate phylogenetic trees for the serine and metallo-β-lactamase superfamilies from the STEEP generated MSA, and corroborated the accepted relationships in these superfamilies. We have observed that STEEP acts as a functional classifier when electrostatic congruence is used as a discriminator, and thus identifies potential targets for directed evolution experiments. In summary, STEEP is unique among phylogenetic methods for its ability to use electrostatic congruence to specify mutations that might be the source of the functional divergence in a protein family. Based on our results, we also hypothesize that the active site and its close vicinity contains enough information to infer the correct phylogeny for related proteins.« less

  10. Sequence harmony: detecting functional specificity from alignments

    PubMed Central

    Feenstra, K. Anton; Pirovano, Walter; Krab, Klaas; Heringa, Jaap

    2007-01-01

    Multiple sequence alignments are often used for the identification of key specificity-determining residues within protein families. We present a web server implementation of the Sequence Harmony (SH) method previously introduced. SH accurately detects subfamily specific positions from a multiple alignment by scoring compositional differences between subfamilies, without imposing conservation. The SH web server allows a quick selection of subtype specific sites from a multiple alignment given a subfamily grouping. In addition, it allows the predicted sites to be directly mapped onto a protein structure and displayed. We demonstrate the use of the SH server using the family of plant mitochondrial alternative oxidases (AOX). In addition, we illustrate the usefulness of combining sequence and structural information by showing that the predicted sites are clustered into a few distinct regions in an AOX homology model. The SH web server can be accessed at www.ibi.vu.nl/programs/seqharmwww. PMID:17584793

  11. Structural Qualification of Composite Airframes

    NASA Technical Reports Server (NTRS)

    Kedward, Keith T.; McCarty, John E.

    1997-01-01

    The development of fundamental approaches for predicting failure and elongation characteristics of fibrous composites are summarized in this document. The research described includes a statistical formulation for individual fiber breakage and fragmentation and clustered fiber breakage, termed macrodefects wherein the aligned composite may represent a structural component such as a reinforcing bar element, a rebar. Experimental work conducted in support of the future exploitation of aligned composite rebar elements is also described. This work discusses the experimental challenges associated with rebar tensile test evaluation and describes initial numerical analyses performed in support of the experimental program.

  12. Simultaneous AFM and fluorescence imaging: A method for aligning an AFM-tip with an excitation beam using a 2D galvanometer

    NASA Astrophysics Data System (ADS)

    Moores, A. N.; Cadby, A. J.

    2018-02-01

    Correlative fluorescence and atomic force microscopy (AFM) imaging is a highly attractive technique for use in biological imaging, enabling force and mechanical measurements of particular structures whose locations are known due to the specificity of fluorescence imaging. The ability to perform these two measurements simultaneously (rather than consecutively with post-processing correlation) is highly valuable because it would allow the mechanical properties of a structure to be tracked over time as changes in the sample occur. We present an instrument which allows simultaneous AFM and fluorescence imaging by aligning an incident fluorescence excitation beam with an AFM-tip. Alignment was performed by calibrating a 2D galvanometer present in the excitation beam path and using it to reposition the incident beam. Two programs were developed (one manual and one automated) which correlate sample features between the AFM and fluorescence images, calculating the distance required to translate the incident beam towards the AFM-tip. Using this method, we were able to obtain beam-tip alignment (and therefore field-of-view alignment) from an offset of >15 μm to within one micron in two iterations of the program. With the program running alongside data acquisition for real-time feedback between AFM and optical images, this offset was maintained over a time period of several hours. Not only does this eliminate the need to image large areas with both techniques to ensure that fields-of-view overlap, but it also raises the possibility of using this instrument for tip-enhanced fluorescence applications, a technique in which super-resolution images have previously been achieved.

  13. Tree decomposition based fast search of RNA structures including pseudoknots in genomes.

    PubMed

    Song, Yinglei; Liu, Chunmei; Malmberg, Russell; Pan, Fangfang; Cai, Liming

    2005-01-01

    Searching genomes for RNA secondary structure with computational methods has become an important approach to the annotation of non-coding RNAs. However, due to the lack of efficient algorithms for accurate RNA structure-sequence alignment, computer programs capable of fast and effectively searching genomes for RNA secondary structures have not been available. In this paper, a novel RNA structure profiling model is introduced based on the notion of a conformational graph to specify the consensus structure of an RNA family. Tree decomposition yields a small tree width t for such conformation graphs (e.g., t = 2 for stem loops and only a slight increase for pseudo-knots). Within this modelling framework, the optimal alignment of a sequence to the structure model corresponds to finding a maximum valued isomorphic subgraph and consequently can be accomplished through dynamic programming on the tree decomposition of the conformational graph in time O(k(t)N(2)), where k is a small parameter; and N is the size of the projiled RNA structure. Experiments show that the application of the alignment algorithm to search in genomes yields the same search accuracy as methods based on a Covariance model with a significant reduction in computation time. In particular; very accurate searches of tmRNAs in bacteria genomes and of telomerase RNAs in yeast genomes can be accomplished in days, as opposed to months required by other methods. The tree decomposition based searching tool is free upon request and can be downloaded at our site h t t p ://w.uga.edu/RNA-informatics/software/index.php.

  14. From Guide to Practice: Improving Your After School Science Program to Increase Student Academic Achievement

    NASA Astrophysics Data System (ADS)

    Taylor, J.

    2013-12-01

    Numerous science organizations, such as NASA, offer educational outreach activities geared towards after school. For some programs, the primary goal is to grow students' love of science. For others, the programs are also intended to increase academic achievement. For those programs looking to support student learning in out-of-school time environments, aligning the program with learning during the classroom day can be a challenge. The Institute for Education Sciences, What Works Clearinghouse, put together a 'Practice Guide' for maximizing learning time beyond the regular school day. These practice guides provide concrete recommendations for educators supported by research. While this guide is not specific to any content or subject-area, the recommendations provided align very well with science education. After school science is often viewed as a fun, dynamic environment for students. Indeed, one of the recommendations to ensure time is structured according to students' needs is to provide relevant and interesting experiences. Given that our after school programs provide such creative environments for students, what other components are needed to promote increased academic achievement? The recommendations provided to academic achievement, include: 1. Align Instruction, 2. Maximize Attendance and Participation, 3. Adapt Instruction, 4. Provide Engaging Experiences, and 5. Evaluate Program. In this session we will examine these five recommendations presented in the Practice Guide, discuss how these strategies align with science programs, and examine what questions each program should address in order to provide experiences that lend themselves to maximizing instruction. Roadblocks and solutions for overcoming challenges in each of the five areas will be presented. Jessica Taylor will present this research based on her role as an author on the Practice Guide, 'Improving Academic Achievement in Out-of-School Time' and her experience working in various informal science programs for NASA.

  15. Triangular Alignment (TAME). A Tensor-based Approach for Higher-order Network Alignment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mohammadi, Shahin; Gleich, David F.; Kolda, Tamara G.

    2015-11-01

    Network alignment is an important tool with extensive applications in comparative interactomics. Traditional approaches aim to simultaneously maximize the number of conserved edges and the underlying similarity of aligned entities. We propose a novel formulation of the network alignment problem that extends topological similarity to higher-order structures and provide a new objective function that maximizes the number of aligned substructures. This objective function corresponds to an integer programming problem, which is NP-hard. Consequently, we approximate this objective function as a surrogate function whose maximization results in a tensor eigenvalue problem. Based on this formulation, we present an algorithm called Triangularmore » AlignMEnt (TAME), which attempts to maximize the number of aligned triangles across networks. We focus on alignment of triangles because of their enrichment in complex networks; however, our formulation and resulting algorithms can be applied to general motifs. Using a case study on the NAPABench dataset, we show that TAME is capable of producing alignments with up to 99% accuracy in terms of aligned nodes. We further evaluate our method by aligning yeast and human interactomes. Our results indicate that TAME outperforms the state-of-art alignment methods both in terms of biological and topological quality of the alignments.« less

  16. AlignMe—a membrane protein sequence alignment web server

    PubMed Central

    Stamm, Marcus; Staritzbichler, René; Khafizov, Kamil; Forrest, Lucy R.

    2014-01-01

    We present a web server for pair-wise alignment of membrane protein sequences, using the program AlignMe. The server makes available two operational modes of AlignMe: (i) sequence to sequence alignment, taking two sequences in fasta format as input, combining information about each sequence from multiple sources and producing a pair-wise alignment (PW mode); and (ii) alignment of two multiple sequence alignments to create family-averaged hydropathy profile alignments (HP mode). For the PW sequence alignment mode, four different optimized parameter sets are provided, each suited to pairs of sequences with a specific similarity level. These settings utilize different types of inputs: (position-specific) substitution matrices, secondary structure predictions and transmembrane propensities from transmembrane predictions or hydrophobicity scales. In the second (HP) mode, each input multiple sequence alignment is converted into a hydrophobicity profile averaged over the provided set of sequence homologs; the two profiles are then aligned. The HP mode enables qualitative comparison of transmembrane topologies (and therefore potentially of 3D folds) of two membrane proteins, which can be useful if the proteins have low sequence similarity. In summary, the AlignMe web server provides user-friendly access to a set of tools for analysis and comparison of membrane protein sequences. Access is available at http://www.bioinfo.mpg.de/AlignMe PMID:24753425

  17. GALAHAD: 1. Pharmacophore identification by hypermolecular alignment of ligands in 3D

    NASA Astrophysics Data System (ADS)

    Richmond, Nicola J.; Abrams, Charlene A.; Wolohan, Philippa R. N.; Abrahamian, Edmond; Willett, Peter; Clark, Robert D.

    2006-09-01

    Alignment of multiple ligands based on shared pharmacophoric and pharmacosteric features is a long-recognized challenge in drug discovery and development. This is particularly true when the spatial overlap between structures is incomplete, in which case no good template molecule is likely to exist. Pair-wise rigid ligand alignment based on linear assignment (the LAMDA algorithm) has the potential to address this problem (Richmond et al. in J Mol Graph Model 23:199-209, 2004). Here we present the version of LAMDA embodied in the GALAHAD program, which carries out multi-way alignments by iterative construction of hypermolecules that retain the aggregate as well as the individual attributes of the ligands. We have also generalized the cost function from being purely atom-based to being one that operates on ionic, hydrogen bonding, hydrophobic and steric features. Finally, we have added the ability to generate useful partial-match 3D search queries from the hypermolecules obtained. By running frozen conformations through the GALAHAD program, one can utilize the extended version of LAMDA to generate pharmacophores and pharmacosteres that agree well with crystal structure alignments for a range of literature datasets, with minor adjustments of the default parameters generating even better models. Allowing for inclusion of partial match constraints in the queries yields pharmacophores that are consistently a superset of full-match pharmacophores identified in previous analyses, with the additional features representing points of potentially beneficial interaction with the target.

  18. R2R--software to speed the depiction of aesthetic consensus RNA secondary structures.

    PubMed

    Weinberg, Zasha; Breaker, Ronald R

    2011-01-04

    With continuing identification of novel structured noncoding RNAs, there is an increasing need to create schematic diagrams showing the consensus features of these molecules. RNA structural diagrams are typically made either with general-purpose drawing programs like Adobe Illustrator, or with automated or interactive programs specific to RNA. Unfortunately, the use of applications like Illustrator is extremely time consuming, while existing RNA-specific programs produce figures that are useful, but usually not of the same aesthetic quality as those produced at great cost in Illustrator. Additionally, most existing RNA-specific applications are designed for drawing single RNA molecules, not consensus diagrams. We created R2R, a computer program that facilitates the generation of aesthetic and readable drawings of RNA consensus diagrams in a fraction of the time required with general-purpose drawing programs. Since the inference of a consensus RNA structure typically requires a multiple-sequence alignment, the R2R user annotates the alignment with commands directing the layout and annotation of the RNA. R2R creates SVG or PDF output that can be imported into Adobe Illustrator, Inkscape or CorelDRAW. R2R can be used to create consensus sequence and secondary structure models for novel RNA structures or to revise models when new representatives for known RNA classes become available. Although R2R does not currently have a graphical user interface, it has proven useful in our efforts to create 100 schematic models of distinct noncoding RNA classes. R2R makes it possible to obtain high-quality drawings of the consensus sequence and structural models of many diverse RNA structures with a more practical amount of effort. R2R software is available at http://breaker.research.yale.edu/R2R and as an Additional file.

  19. A generalized global alignment algorithm.

    PubMed

    Huang, Xiaoqiu; Chao, Kun-Mao

    2003-01-22

    Homologous sequences are sometimes similar over some regions but different over other regions. Homologous sequences have a much lower global similarity if the different regions are much longer than the similar regions. We present a generalized global alignment algorithm for comparing sequences with intermittent similarities, an ordered list of similar regions separated by different regions. A generalized global alignment model is defined to handle sequences with intermittent similarities. A dynamic programming algorithm is designed to compute an optimal general alignment in time proportional to the product of sequence lengths and in space proportional to the sum of sequence lengths. The algorithm is implemented as a computer program named GAP3 (Global Alignment Program Version 3). The generalized global alignment model is validated by experimental results produced with GAP3 on both DNA and protein sequences. The GAP3 program extends the ability of standard global alignment programs to recognize homologous sequences of lower similarity. The GAP3 program is freely available for academic use at http://bioinformatics.iastate.edu/aat/align/align.html.

  20. A molecular-field-based similarity study of non-nucleoside HIV-1 reverse transcriptase inhibitors

    NASA Astrophysics Data System (ADS)

    Mestres, Jordi; Rohrer, Douglas C.; Maggiora, Gerald M.

    1999-01-01

    This article describes a molecular-field-based similarity method for aligning molecules by matching their steric and electrostatic fields and an application of the method to the alignment of three structurally diverse non-nucleoside HIV-1 reverse transcriptase inhibitors. A brief description of the method, as implemented in the program MIMIC, is presented, including a discussion of pairwise and multi-molecule similarity-based matching. The application provides an example that illustrates how relative binding orientations of molecules can be determined in the absence of detailed structural information on their target protein. In the particular system studied here, availability of the X-ray crystal structures of the respective ligand-protein complexes provides a means for constructing an 'experimental model' of the relative binding orientations of the three inhibitors. The experimental model is derived by using MIMIC to align the steric fields of the three protein P66 subunit main chains, producing an overlay with a 1.41 Å average rms distance between the corresponding Cα's in the three chains. The inter-chain residue similarities for the backbone structures show that the main-chain conformations are conserved in the region of the inhibitor-binding site, with the major deviations located primarily in the 'finger' and RNase H regions. The resulting inhibitor structure overlay provides an experimental-based model that can be used to evaluate the quality of the direct a priori inhibitor alignment obtained using MIMIC. It is found that the 'best' pairwise alignments do not always correspond to the experimental model alignments. Therefore, simply combining the best pairwise alignments will not necessarily produce the optimal multi-molecule alignment. However, the best simultaneous three-molecule alignment was found to reproduce the experimental inhibitor alignment model. A pairwise consistency index has been derived which gauges the quality of combining the pairwise alignments and aids in efficiently forming the optimal multi-molecule alignment analysis. Two post-alignment procedures are described that provide information on feature-based and field-based pharmacophoric patterns. The former corresponds to traditional pharmacophore models and is derived from the contribution of individual atoms to the total similarity. The latter is based on molecular regions rather than atoms and is constructed by computing the percent contribution to the similarity of individual points in a regular lattice surrounding the molecules, which when contoured and colored visually depict regions of highly conserved similarity. A discussion of how the information provided by each of the procedures is useful in drug design is also presented.

  1. History of Reliability and Quality Assurance at Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Childers, Frank M.

    2004-01-01

    This Kennedy Historical Document (KHD) provides a unique historical perspective of the organizational and functional responsibilities for the manned and un-manned programs at Kennedy Space Center, Florida. As systems become more complex and hazardous, the attention to detailed planning and execution continues to be a challenge. The need for a robust reliability and quality assurance program will always be a necessity to ensure mission success. As new space missions are defined and technology allows for continued access to space, these programs cannot be compromised. The organizational structure that has provided the reliability and quality assurance functions for both the manned and unmanned programs has seen many changes since the first group came to Florida in the 1950's. The roles of government and contractor personnel have changed with each program and organizational alignment has changed based on that responsibility. The organizational alignment of the personnel performing these functions must ensure independent assessment of the processes.

  2. Special test equipment and fixturing for MSAT reflector assembly alignment

    NASA Technical Reports Server (NTRS)

    Young, Jeffrey A.; Zinn, Michael R.; Mccarten, David R.

    1994-01-01

    The MSAT Reflector Assembly is a state of the art subsystem for Mobile Satellite (MSAT), a geosynchronous-based commercial mobile telecommunication satellite program serving North America. The Reflector Assembly consisted of a deployable, three-hinge, folding-segment Boom, deployable 5.7 x 5.3-meter 16-rib Wrap-Rib Reflector, and a Reflector Pointing Mechanism (RPM). The MSAT spacecraft was based on a Hughes HS601 spacecraft bus carrying two Reflector Assemblies independently dedicated for L-band transmit and receive operations. Lockheed Missiles and Space Company (LMSC) designed and built the Reflector Assembly for MSAT under contract to SPAR Aerospace Ltd. Two MSAT satellites were built jointly by SPAR Aerospace Ltd. and Hughes Space and Communications Co. for this program, the first scheduled for launch in 1994. When scaled for wavelength, the assembly and alignment requirements for the Reflector Assembly were in many instances equivalent to or exceeded that of a diffraction-limited visible light optical system. Combined with logistical constraints inherent to large, compliant, lightweight structures; 'bolt-on' alignment; and remote, indirect spacecraft access; the technical challenges were formidable. This document describes the alignment methods, the special test equipment, and fixturing for Reflector Assembly assembly and alignment.

  3. Focusing on learning through constructive alignment with task-oriented portfolio assessment

    NASA Astrophysics Data System (ADS)

    Cain, A.; Grundy, J.; Woodward, C. J.

    2018-07-01

    Approaches to learning have been shown to have a significant impact on student success in technical units. This paper reports on an action research study that applied the principles of constructive alignment to improve student learning outcomes in programming units. The proposed model uses frequent formative feedback to engage students with unit material, and encourage them to adopt deep approaches to learning. Our results provide a set of guiding principles and a structured teaching approach that focuses students on meeting unit learning objectives, the goal of constructive alignment. The results are demonstrated via descriptions of the resulting teaching and learning environment, student results, and staff and student reflections.

  4. Filamentary field-aligned currents at the polar cap region during northward interplanetary magnetic field derived with the Swarm constellation

    PubMed Central

    Lühr, Hermann; Huang, Tao; Wing, Simon; Kervalishvili, Guram; Rauberg, Jan; Korth, Haje

    2017-01-01

    ESA’s Swarm constellation mission makes it possible for the first time to determine field-aligned currents (FACs) in the ionosphere uniquely. In particular at high latitudes, the dual-satellite approach can reliably detect some FAC structures which are missed by the traditional single-satellite technique. These FAC events occur preferentially poleward of the auroral oval and during times of northward interplanetary magnetic field (IMF) orientation. Most events appear on the nightside. They are not related to the typical FAC structures poleward of the cusp, commonly termed NBZ. Simultaneously observed precipitating particle spectrograms and auroral images from Defense Meteorological Satellite Program (DMSP) satellites are consistent with the detected FACs and indicate that they occur on closed field lines mostly adjacent to the auroral oval. We suggest that the FACs are associated with Sun-aligned filamentary auroral arcs. Here we introduce in an initial study features of the high-latitude FAC structures which have been observed during the early phase of the Swarm mission. A more systematic survey over longer times is required to fully characterize the so far undetected field aligned currents. PMID:29056833

  5. What can the past of pay-for-performance tell us about the future of Value-Based Purchasing in Medicare?

    PubMed

    Ryan, Andrew M; Damberg, Cheryl L

    2013-06-01

    The Medicare program has implemented pay-for-performance (P4P), or Value-Based Purchasing, for inpatient care and for Medicare Advantage plans, and plans to implement a program for physicians in 2015. In this paper, we review evidence on the effectiveness of P4P and identify design criteria deemed to be best practice in P4P. We then assess the extent to which Medicare's existing and planned Value-Based Purchasing programs align with these best practices. Of the seven identified best practices in P4P program design, the Hospital Value-Based Purchasing program is strongly aligned with two of the best practices, moderately aligned with three, weakly aligned with one, and has unclear alignment with one best practice. The Physician Value-Based Purchasing Modifier is strongly aligned with two of the best practices, moderately aligned with one, weakly aligned with three, and has unclear alignment with one of the best practices. The Medicare Advantage Quality Bonus Program is strongly aligned with four of the best practices, moderately aligned with two, and weakly aligned with one of the best practices. We identify enduring gaps in P4P literature as it relates to Medicare's plans for Value-Based Purchasing and discuss important issues in the future of these implementations in Medicare. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Accelerating large-scale protein structure alignments with graphics processing units

    PubMed Central

    2012-01-01

    Background Large-scale protein structure alignment, an indispensable tool to structural bioinformatics, poses a tremendous challenge on computational resources. To ensure structure alignment accuracy and efficiency, efforts have been made to parallelize traditional alignment algorithms in grid environments. However, these solutions are costly and of limited accessibility. Others trade alignment quality for speedup by using high-level characteristics of structure fragments for structure comparisons. Findings We present ppsAlign, a parallel protein structure Alignment framework designed and optimized to exploit the parallelism of Graphics Processing Units (GPUs). As a general-purpose GPU platform, ppsAlign could take many concurrent methods, such as TM-align and Fr-TM-align, into the parallelized algorithm design. We evaluated ppsAlign on an NVIDIA Tesla C2050 GPU card, and compared it with existing software solutions running on an AMD dual-core CPU. We observed a 36-fold speedup over TM-align, a 65-fold speedup over Fr-TM-align, and a 40-fold speedup over MAMMOTH. Conclusions ppsAlign is a high-performance protein structure alignment tool designed to tackle the computational complexity issues from protein structural data. The solution presented in this paper allows large-scale structure comparisons to be performed using massive parallel computing power of GPU. PMID:22357132

  7. CombAlign: a code for generating a one-to-many sequence alignment from a set of pairwise structure-based sequence alignments.

    PubMed

    Zhou, Carol L Ecale

    2015-01-01

    In order to better define regions of similarity among related protein structures, it is useful to identify the residue-residue correspondences among proteins. Few codes exist for constructing a one-to-many multiple sequence alignment derived from a set of structure or sequence alignments, and a need was evident for creating such a tool for combining pairwise structure alignments that would allow for insertion of gaps in the reference structure. This report describes a new Python code, CombAlign, which takes as input a set of pairwise sequence alignments (which may be structure based) and generates a one-to-many, gapped, multiple structure- or sequence-based sequence alignment (MSSA). The use and utility of CombAlign was demonstrated by generating gapped MSSAs using sets of pairwise structure-based sequence alignments between structure models of the matrix protein (VP40) and pre-small/secreted glycoprotein (sGP) of Reston Ebolavirus and the corresponding proteins of several other filoviruses. The gapped MSSAs revealed structure-based residue-residue correspondences, which enabled identification of structurally similar versus differing regions in the Reston proteins compared to each of the other corresponding proteins. CombAlign is a new Python code that generates a one-to-many, gapped, multiple structure- or sequence-based sequence alignment (MSSA) given a set of pairwise sequence alignments (which may be structure based). CombAlign has utility in assisting the user in distinguishing structurally conserved versus divergent regions on a reference protein structure relative to other closely related proteins. CombAlign was developed in Python 2.6, and the source code is available for download from the GitHub code repository.

  8. SNAPPI-DB: a database and API of Structures, iNterfaces and Alignments for Protein–Protein Interactions

    PubMed Central

    Jefferson, Emily R.; Walsh, Thomas P.; Roberts, Timothy J.; Barton, Geoffrey J.

    2007-01-01

    SNAPPI-DB, a high performance database of Structures, iNterfaces and Alignments of Protein–Protein Interactions, and its associated Java Application Programming Interface (API) is described. SNAPPI-DB contains structural data, down to the level of atom co-ordinates, for each structure in the Protein Data Bank (PDB) together with associated data including SCOP, CATH, Pfam, SWISSPROT, InterPro, GO terms, Protein Quaternary Structures (PQS) and secondary structure information. Domain–domain interactions are stored for multiple domain definitions and are classified by their Superfamily/Family pair and interaction interface. Each set of classified domain–domain interactions has an associated multiple structure alignment for each partner. The API facilitates data access via PDB entries, domains and domain–domain interactions. Rapid development, fast database access and the ability to perform advanced queries without the requirement for complex SQL statements are provided via an object oriented database and the Java Data Objects (JDO) API. SNAPPI-DB contains many features which are not available in other databases of structural protein–protein interactions. It has been applied in three studies on the properties of protein–protein interactions and is currently being employed to train a protein–protein interaction predictor and a functional residue predictor. The database, API and manual are available for download at: . PMID:17202171

  9. Fine-tuning structural RNA alignments in the twilight zone.

    PubMed

    Bremges, Andreas; Schirmer, Stefanie; Giegerich, Robert

    2010-04-30

    A widely used method to find conserved secondary structure in RNA is to first construct a multiple sequence alignment, and then fold the alignment, optimizing a score based on thermodynamics and covariance. This method works best around 75% sequence similarity. However, in a "twilight zone" below 55% similarity, the sequence alignment tends to obscure the covariance signal used in the second phase. Therefore, while the overall shape of the consensus structure may still be found, the degree of conservation cannot be estimated reliably. Based on a combination of available methods, we present a method named planACstar for improving structure conservation in structural alignments in the twilight zone. After constructing a consensus structure by alignment folding, planACstar abandons the original sequence alignment, refolds the sequences individually, but consistent with the consensus, aligns the structures, irrespective of sequence, by a pure structure alignment method, and derives an improved sequence alignment from the alignment of structures, to be re-submitted to alignment folding, etc.. This circle may be iterated as long as structural conservation improves, but normally, one step suffices. Employing the tools ClustalW, RNAalifold, and RNAforester, we find that for sequences with 30-55% sequence identity, structural conservation can be improved by 10% on average, with a large variation, measured in terms of RNAalifold's own criterion, the structure conservation index.

  10. A new version of the RDP (Ribosomal Database Project)

    NASA Technical Reports Server (NTRS)

    Maidak, B. L.; Cole, J. R.; Parker, C. T. Jr; Garrity, G. M.; Larsen, N.; Li, B.; Lilburn, T. G.; McCaughey, M. J.; Olsen, G. J.; Overbeek, R.; hide

    1999-01-01

    The Ribosomal Database Project (RDP-II), previously described by Maidak et al. [ Nucleic Acids Res. (1997), 25, 109-111], is now hosted by the Center for Microbial Ecology at Michigan State University. RDP-II is a curated database that offers ribosomal RNA (rRNA) nucleotide sequence data in aligned and unaligned forms, analysis services, and associated computer programs. During the past two years, data alignments have been updated and now include >9700 small subunit rRNA sequences. The recent development of an ObjectStore database will provide more rapid updating of data, better data accuracy and increased user access. RDP-II includes phylogenetically ordered alignments of rRNA sequences, derived phylogenetic trees, rRNA secondary structure diagrams, and various software programs for handling, analyzing and displaying alignments and trees. The data are available via anonymous ftp (ftp.cme.msu. edu) and WWW (http://www.cme.msu.edu/RDP). The WWW server provides ribosomal probe checking, approximate phylogenetic placement of user-submitted sequences, screening for possible chimeric rRNA sequences, automated alignment, and a suggested placement of an unknown sequence on an existing phylogenetic tree. Additional utilities also exist at RDP-II, including distance matrix, T-RFLP, and a Java-based viewer of the phylogenetic trees that can be used to create subtrees.

  11. Structuring an MBA Consulting Course: Aligning Pedagogical Strategies to Meet the Needs of a Business School's Critical Stakeholders

    ERIC Educational Resources Information Center

    Roche, Olivier P.; Downie, Yvonne; Diriker, Memo

    2013-01-01

    At a time when business schools of second-tieruniversities face budget constraints, the MBA consulting program has become avehicle to build a school's reputation and to engage the business community inorder to raise financial resources. Business schools also face competition fromon-line programs, and consulting assignments help to define a…

  12. Fine-tuning structural RNA alignments in the twilight zone

    PubMed Central

    2010-01-01

    Background A widely used method to find conserved secondary structure in RNA is to first construct a multiple sequence alignment, and then fold the alignment, optimizing a score based on thermodynamics and covariance. This method works best around 75% sequence similarity. However, in a "twilight zone" below 55% similarity, the sequence alignment tends to obscure the covariance signal used in the second phase. Therefore, while the overall shape of the consensus structure may still be found, the degree of conservation cannot be estimated reliably. Results Based on a combination of available methods, we present a method named planACstar for improving structure conservation in structural alignments in the twilight zone. After constructing a consensus structure by alignment folding, planACstar abandons the original sequence alignment, refolds the sequences individually, but consistent with the consensus, aligns the structures, irrespective of sequence, by a pure structure alignment method, and derives an improved sequence alignment from the alignment of structures, to be re-submitted to alignment folding, etc.. This circle may be iterated as long as structural conservation improves, but normally, one step suffices. Conclusions Employing the tools ClustalW, RNAalifold, and RNAforester, we find that for sequences with 30-55% sequence identity, structural conservation can be improved by 10% on average, with a large variation, measured in terms of RNAalifold's own criterion, the structure conservation index. PMID:20433706

  13. New Directions in NASA's Materials Science Program

    NASA Technical Reports Server (NTRS)

    Gillies, Donald C.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Recently, NASA's Microgravity Research Division was re-aligned to match the Agency's increasing awareness of the importance of biological and nano-structural sciences. The Division has become the Physical Sciences Research section within the newly created Office of Biological and Physical Research. Within materials science and in the last few years, new programs aimed at biomaterials have been initiated. Results from these programs and also new research pertaining to materials for radiation protection will be discussed.

  14. Automated protein structure modeling in CASP9 by I-TASSER pipeline combined with QUARK-based ab initio folding and FG-MD-based structure refinement

    PubMed Central

    Xu, Dong; Zhang, Jian; Roy, Ambrish; Zhang, Yang

    2011-01-01

    I-TASSER is an automated pipeline for protein tertiary structure prediction using multiple threading alignments and iterative structure assembly simulations. In CASP9 experiments, two new algorithms, QUARK and FG-MD, were added to the I-TASSER pipeline for improving the structural modeling accuracy. QUARK is a de novo structure prediction algorithm used for structure modeling of proteins that lack detectable template structures. For distantly homologous targets, QUARK models are found useful as a reference structure for selecting good threading alignments and guiding the I-TASSER structure assembly simulations. FG-MD is an atomic-level structural refinement program that uses structural fragments collected from the PDB structures to guide molecular dynamics simulation and improve the local structure of predicted model, including hydrogen-bonding networks, torsion angles and steric clashes. Despite considerable progress in both the template-based and template-free structure modeling, significant improvements on protein target classification, domain parsing, model selection, and ab initio folding of beta-proteins are still needed to further improve the I-TASSER pipeline. PMID:22069036

  15. Estimating Relative Positions of Outer-Space Structures

    NASA Technical Reports Server (NTRS)

    Balian, Harry; Breckenridge, William; Brugarolas, Paul

    2009-01-01

    A computer program estimates the relative position and orientation of two structures from measurements, made by use of electronic cameras and laser range finders on one structure, of distances and angular positions of fiducial objects on the other structure. The program was written specifically for use in determining errors in the alignment of large structures deployed in outer space from a space shuttle. The program is based partly on equations for transformations among the various coordinate systems involved in the measurements and on equations that account for errors in the transformation operators. It computes a least-squares estimate of the relative position and orientation. Sequential least-squares estimates, acquired at a measurement rate of 4 Hz, are averaged by passing them through a fourth-order Butterworth filter. The program is executed in a computer aboard the space shuttle, and its position and orientation estimates are displayed to astronauts on a graphical user interface.

  16. Reverse alignment "mirror image" visualization as a laparoscopic training tool improves task performance.

    PubMed

    Dunnican, Ward J; Singh, T Paul; Ata, Ashar; Bendana, Emma E; Conlee, Thomas D; Dolce, Charles J; Ramakrishnan, Rakesh

    2010-06-01

    Reverse alignment (mirror image) visualization is a disconcerting situation occasionally faced during laparoscopic operations. This occurs when the camera faces back at the surgeon in the opposite direction from which the surgeon's body and instruments are facing. Most surgeons will attempt to optimize trocar and camera placement to avoid this situation. The authors' objective was to determine whether the intentional use of reverse alignment visualization during laparoscopic training would improve performance. A standard box trainer was configured for reverse alignment, and 34 medical students and junior surgical residents were randomized to train with either forward alignment (DIRECT) or reverse alignment (MIRROR) visualization. Enrollees were tested on both modalities before and after a 4-week structured training program specific to their modality. Student's t test was used to determine differences in task performance between the 2 groups. Twenty-one participants completed the study (10 DIRECT, 11 MIRROR). There were no significant differences in performance time between DIRECT or MIRROR participants during forward or reverse alignment initial testing. At final testing, DIRECT participants had improved times only in forward alignment performance; they demonstrated no significant improvement in reverse alignment performance. MIRROR participants had significant time improvement in both forward and reverse alignment performance at final testing. Reverse alignment imaging for laparoscopic training improves task performance for both reverse alignment and forward alignment tasks. This may be translated into improved performance in the operating room when faced with reverse alignment situations. Minimal lab training can account for drastic adaptation to this environment.

  17. R2R - software to speed the depiction of aesthetic consensus RNA secondary structures

    PubMed Central

    2011-01-01

    Background With continuing identification of novel structured noncoding RNAs, there is an increasing need to create schematic diagrams showing the consensus features of these molecules. RNA structural diagrams are typically made either with general-purpose drawing programs like Adobe Illustrator, or with automated or interactive programs specific to RNA. Unfortunately, the use of applications like Illustrator is extremely time consuming, while existing RNA-specific programs produce figures that are useful, but usually not of the same aesthetic quality as those produced at great cost in Illustrator. Additionally, most existing RNA-specific applications are designed for drawing single RNA molecules, not consensus diagrams. Results We created R2R, a computer program that facilitates the generation of aesthetic and readable drawings of RNA consensus diagrams in a fraction of the time required with general-purpose drawing programs. Since the inference of a consensus RNA structure typically requires a multiple-sequence alignment, the R2R user annotates the alignment with commands directing the layout and annotation of the RNA. R2R creates SVG or PDF output that can be imported into Adobe Illustrator, Inkscape or CorelDRAW. R2R can be used to create consensus sequence and secondary structure models for novel RNA structures or to revise models when new representatives for known RNA classes become available. Although R2R does not currently have a graphical user interface, it has proven useful in our efforts to create 100 schematic models of distinct noncoding RNA classes. Conclusions R2R makes it possible to obtain high-quality drawings of the consensus sequence and structural models of many diverse RNA structures with a more practical amount of effort. R2R software is available at http://breaker.research.yale.edu/R2R and as an Additional file. PMID:21205310

  18. mTM-align: a server for fast protein structure database search and multiple protein structure alignment.

    PubMed

    Dong, Runze; Pan, Shuo; Peng, Zhenling; Zhang, Yang; Yang, Jianyi

    2018-05-21

    With the rapid increase of the number of protein structures in the Protein Data Bank, it becomes urgent to develop algorithms for efficient protein structure comparisons. In this article, we present the mTM-align server, which consists of two closely related modules: one for structure database search and the other for multiple structure alignment. The database search is speeded up based on a heuristic algorithm and a hierarchical organization of the structures in the database. The multiple structure alignment is performed using the recently developed algorithm mTM-align. Benchmark tests demonstrate that our algorithms outperform other peering methods for both modules, in terms of speed and accuracy. One of the unique features for the server is the interplay between database search and multiple structure alignment. The server provides service not only for performing fast database search, but also for making accurate multiple structure alignment with the structures found by the search. For the database search, it takes about 2-5 min for a structure of a medium size (∼300 residues). For the multiple structure alignment, it takes a few seconds for ∼10 structures of medium sizes. The server is freely available at: http://yanglab.nankai.edu.cn/mTM-align/.

  19. SFESA: a web server for pairwise alignment refinement by secondary structure shifts.

    PubMed

    Tong, Jing; Pei, Jimin; Grishin, Nick V

    2015-09-03

    Protein sequence alignment is essential for a variety of tasks such as homology modeling and active site prediction. Alignment errors remain the main cause of low-quality structure models. A bioinformatics tool to refine alignments is needed to make protein alignments more accurate. We developed the SFESA web server to refine pairwise protein sequence alignments. Compared to the previous version of SFESA, which required a set of 3D coordinates for a protein, the new server will search a sequence database for the closest homolog with an available 3D structure to be used as a template. For each alignment block defined by secondary structure elements in the template, SFESA evaluates alignment variants generated by local shifts and selects the best-scoring alignment variant. A scoring function that combines the sequence score of profile-profile comparison and the structure score of template-derived contact energy is used for evaluation of alignments. PROMALS pairwise alignments refined by SFESA are more accurate than those produced by current advanced alignment methods such as HHpred and CNFpred. In addition, SFESA also improves alignments generated by other software. SFESA is a web-based tool for alignment refinement, designed for researchers to compute, refine, and evaluate pairwise alignments with a combined sequence and structure scoring of alignment blocks. To our knowledge, the SFESA web server is the only tool that refines alignments by evaluating local shifts of secondary structure elements. The SFESA web server is available at http://prodata.swmed.edu/sfesa.

  20. R3D Align web server for global nucleotide to nucleotide alignments of RNA 3D structures.

    PubMed

    Rahrig, Ryan R; Petrov, Anton I; Leontis, Neocles B; Zirbel, Craig L

    2013-07-01

    The R3D Align web server provides online access to 'RNA 3D Align' (R3D Align), a method for producing accurate nucleotide-level structural alignments of RNA 3D structures. The web server provides a streamlined and intuitive interface, input data validation and output that is more extensive and easier to read and interpret than related servers. The R3D Align web server offers a unique Gallery of Featured Alignments, providing immediate access to pre-computed alignments of large RNA 3D structures, including all ribosomal RNAs, as well as guidance on effective use of the server and interpretation of the output. By accessing the non-redundant lists of RNA 3D structures provided by the Bowling Green State University RNA group, R3D Align connects users to structure files in the same equivalence class and the best-modeled representative structure from each group. The R3D Align web server is freely accessible at http://rna.bgsu.edu/r3dalign/.

  1. Progressive structure-based alignment of homologous proteins: Adopting sequence comparison strategies.

    PubMed

    Joseph, Agnel Praveen; Srinivasan, Narayanaswamy; de Brevern, Alexandre G

    2012-09-01

    Comparison of multiple protein structures has a broad range of applications in the analysis of protein structure, function and evolution. Multiple structure alignment tools (MSTAs) are necessary to obtain a simultaneous comparison of a family of related folds. In this study, we have developed a method for multiple structure comparison largely based on sequence alignment techniques. A widely used Structural Alphabet named Protein Blocks (PBs) was used to transform the information on 3D protein backbone conformation as a 1D sequence string. A progressive alignment strategy similar to CLUSTALW was adopted for multiple PB sequence alignment (mulPBA). Highly similar stretches identified by the pairwise alignments are given higher weights during the alignment. The residue equivalences from PB based alignments are used to obtain a three dimensional fit of the structures followed by an iterative refinement of the structural superposition. Systematic comparisons using benchmark datasets of MSTAs underlines that the alignment quality is better than MULTIPROT, MUSTANG and the alignments in HOMSTRAD, in more than 85% of the cases. Comparison with other rigid-body and flexible MSTAs also indicate that mulPBA alignments are superior to most of the rigid-body MSTAs and highly comparable to the flexible alignment methods. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  2. Fast and accurate non-sequential protein structure alignment using a new asymmetric linear sum assignment heuristic.

    PubMed

    Brown, Peter; Pullan, Wayne; Yang, Yuedong; Zhou, Yaoqi

    2016-02-01

    The three dimensional tertiary structure of a protein at near atomic level resolution provides insight alluding to its function and evolution. As protein structure decides its functionality, similarity in structure usually implies similarity in function. As such, structure alignment techniques are often useful in the classifications of protein function. Given the rapidly growing rate of new, experimentally determined structures being made available from repositories such as the Protein Data Bank, fast and accurate computational structure comparison tools are required. This paper presents SPalignNS, a non-sequential protein structure alignment tool using a novel asymmetrical greedy search technique. The performance of SPalignNS was evaluated against existing sequential and non-sequential structure alignment methods by performing trials with commonly used datasets. These benchmark datasets used to gauge alignment accuracy include (i) 9538 pairwise alignments implied by the HOMSTRAD database of homologous proteins; (ii) a subset of 64 difficult alignments from set (i) that have low structure similarity; (iii) 199 pairwise alignments of proteins with similar structure but different topology; and (iv) a subset of 20 pairwise alignments from the RIPC set. SPalignNS is shown to achieve greater alignment accuracy (lower or comparable root-mean squared distance with increased structure overlap coverage) for all datasets, and the highest agreement with reference alignments from the challenging dataset (iv) above, when compared with both sequentially constrained alignments and other non-sequential alignments. SPalignNS was implemented in C++. The source code, binary executable, and a web server version is freely available at: http://sparks-lab.org yaoqi.zhou@griffith.edu.au. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Comparative Protein Structure Modeling Using MODELLER.

    PubMed

    Webb, Benjamin; Sali, Andrej

    2014-09-08

    Functional characterization of a protein sequence is one of the most frequent problems in biology. This task is usually facilitated by accurate three-dimensional (3-D) structure of the studied protein. In the absence of an experimentally determined structure, comparative or homology modeling can sometimes provide a useful 3-D model for a protein that is related to at least one known protein structure. Comparative modeling predicts the 3-D structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. Copyright © 2014 John Wiley & Sons, Inc.

  4. Control superstructure of rigid polyelectrolytes in oppositely charged hydrogels via programmed internal stress

    NASA Astrophysics Data System (ADS)

    Takahashi, Riku; Wu, Zi Liang; Arifuzzaman, Md; Nonoyama, Takayuki; Nakajima, Tasuku; Kurokawa, Takayuki; Gong, Jian Ping

    2014-08-01

    Biomacromolecules usually form complex superstructures in natural biotissues, such as different alignments of collagen fibres in articular cartilages, for multifunctionalities. Inspired by nature, there are efforts towards developing multiscale ordered structures in hydrogels (recognized as one of the best candidates of soft biotissues). However, creating complex superstructures in gels are hardly realized because of the absence of effective approaches to control the localized molecular orientation. Here we introduce a method to create various superstructures of rigid polyanions in polycationic hydrogels. The control of localized orientation of rigid molecules, which are sensitive to the internal stress field of the gel, is achieved by tuning the swelling mismatch between masked and unmasked regions of the photolithographic patterned gel. Furthermore, we develop a double network structure to toughen the hydrogels with programmed superstructures, which deform reversibly under large strain. This work presents a promising pathway to develop superstructures in hydrogels and should shed light on designing biomimetic materials with intricate molecular alignments.

  5. Automated identification of RNA 3D modules with discriminative power in RNA structural alignments.

    PubMed

    Theis, Corinna; Höner Zu Siederdissen, Christian; Hofacker, Ivo L; Gorodkin, Jan

    2013-12-01

    Recent progress in predicting RNA structure is moving towards filling the 'gap' in 2D RNA structure prediction where, for example, predicted internal loops often form non-canonical base pairs. This is increasingly recognized with the steady increase of known RNA 3D modules. There is a general interest in matching structural modules known from one molecule to other molecules for which the 3D structure is not known yet. We have created a pipeline, metaRNAmodules, which completely automates extracting putative modules from the FR3D database and mapping of such modules to Rfam alignments to obtain comparative evidence. Subsequently, the modules, initially represented by a graph, are turned into models for the RMDetect program, which allows to test their discriminative power using real and randomized Rfam alignments. An initial extraction of 22 495 3D modules in all PDB files results in 977 internal loop and 17 hairpin modules with clear discriminatory power. Many of these modules describe only minor variants of each other. Indeed, mapping of the modules onto Rfam families results in 35 unique locations in 11 different families. The metaRNAmodules pipeline source for the internal loop modules is available at http://rth.dk/resources/mrm.

  6. SARA-Coffee web server, a tool for the computation of RNA sequence and structure multiple alignments

    PubMed Central

    Di Tommaso, Paolo; Bussotti, Giovanni; Kemena, Carsten; Capriotti, Emidio; Chatzou, Maria; Prieto, Pablo; Notredame, Cedric

    2014-01-01

    This article introduces the SARA-Coffee web server; a service allowing the online computation of 3D structure based multiple RNA sequence alignments. The server makes it possible to combine sequences with and without known 3D structures. Given a set of sequences SARA-Coffee outputs a multiple sequence alignment along with a reliability index for every sequence, column and aligned residue. SARA-Coffee combines SARA, a pairwise structural RNA aligner with the R-Coffee multiple RNA aligner in a way that has been shown to improve alignment accuracy over most sequence aligners when enough structural data is available. The server can be accessed from http://tcoffee.crg.cat/apps/tcoffee/do:saracoffee. PMID:24972831

  7. R3D-2-MSA: the RNA 3D structure-to-multiple sequence alignment server

    PubMed Central

    Cannone, Jamie J.; Sweeney, Blake A.; Petrov, Anton I.; Gutell, Robin R.; Zirbel, Craig L.; Leontis, Neocles

    2015-01-01

    The RNA 3D Structure-to-Multiple Sequence Alignment Server (R3D-2-MSA) is a new web service that seamlessly links RNA three-dimensional (3D) structures to high-quality RNA multiple sequence alignments (MSAs) from diverse biological sources. In this first release, R3D-2-MSA provides manual and programmatic access to curated, representative ribosomal RNA sequence alignments from bacterial, archaeal, eukaryal and organellar ribosomes, using nucleotide numbers from representative atomic-resolution 3D structures. A web-based front end is available for manual entry and an Application Program Interface for programmatic access. Users can specify up to five ranges of nucleotides and 50 nucleotide positions per range. The R3D-2-MSA server maps these ranges to the appropriate columns of the corresponding MSA and returns the contents of the columns, either for display in a web browser or in JSON format for subsequent programmatic use. The browser output page provides a 3D interactive display of the query, a full list of sequence variants with taxonomic information and a statistical summary of distinct sequence variants found. The output can be filtered and sorted in the browser. Previous user queries can be viewed at any time by resubmitting the output URL, which encodes the search and re-generates the results. The service is freely available with no login requirement at http://rna.bgsu.edu/r3d-2-msa. PMID:26048960

  8. Creating a meaningful infection control program: one home healthcare agency's lessons.

    PubMed

    Poff, Renee McCoy; Browning, Sarah Via

    2014-03-01

    Creating a meaningful infection control program in the home care setting proved to be challenging for agency leaders of one hospital-based home healthcare agency. Challenges arose when agency leaders provided infection control (IC) data to the hospital's IC Committee. The IC Section Chief asked for national benchmark comparisons to align home healthcare reporting to that of the hospital level. At that point, it was evident that the home healthcare IC program lacked definition and structure. The purpose of this article is to share how one agency built a meaningful IC program.

  9. Industrial Hygiene Technologist Model. Final Report.

    ERIC Educational Resources Information Center

    Joliet Junior Coll., IL.

    A project revised the existing Occupational Safety Program at Joliet Junior College (JJC) to indicate an AAS degree option in Industrial Hygiene Technology (IHT). Its objectives were to (1) utilize, where possible, existing courses within the college's curricula; (2) align the structure of the proposed curriculum with accreditation/certification…

  10. DIALIGN P: fast pair-wise and multiple sequence alignment using parallel processors.

    PubMed

    Schmollinger, Martin; Nieselt, Kay; Kaufmann, Michael; Morgenstern, Burkhard

    2004-09-09

    Parallel computing is frequently used to speed up computationally expensive tasks in Bioinformatics. Herein, a parallel version of the multi-alignment program DIALIGN is introduced. We propose two ways of dividing the program into independent sub-routines that can be run on different processors: (a) pair-wise sequence alignments that are used as a first step to multiple alignment account for most of the CPU time in DIALIGN. Since alignments of different sequence pairs are completely independent of each other, they can be distributed to multiple processors without any effect on the resulting output alignments. (b) For alignments of large genomic sequences, we use a heuristics by splitting up sequences into sub-sequences based on a previously introduced anchored alignment procedure. For our test sequences, this combined approach reduces the program running time of DIALIGN by up to 97%. By distributing sub-routines to multiple processors, the running time of DIALIGN can be crucially improved. With these improvements, it is possible to apply the program in large-scale genomics and proteomics projects that were previously beyond its scope.

  11. Hal: an automated pipeline for phylogenetic analyses of genomic data.

    PubMed

    Robbertse, Barbara; Yoder, Ryan J; Boyd, Alex; Reeves, John; Spatafora, Joseph W

    2011-02-07

    The rapid increase in genomic and genome-scale data is resulting in unprecedented levels of discrete sequence data available for phylogenetic analyses. Major analytical impasses exist, however, prior to analyzing these data with existing phylogenetic software. Obstacles include the management of large data sets without standardized naming conventions, identification and filtering of orthologous clusters of proteins or genes, and the assembly of alignments of orthologous sequence data into individual and concatenated super alignments. Here we report the production of an automated pipeline, Hal that produces multiple alignments and trees from genomic data. These alignments can be produced by a choice of four alignment programs and analyzed by a variety of phylogenetic programs. In short, the Hal pipeline connects the programs BLASTP, MCL, user specified alignment programs, GBlocks, ProtTest and user specified phylogenetic programs to produce species trees. The script is available at sourceforge (http://sourceforge.net/projects/bio-hal/). The results from an example analysis of Kingdom Fungi are briefly discussed.

  12. Post-Flight Estimation of Motion of Space Structures: Part 1

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul; Breckenridge, William

    2008-01-01

    A computer program estimates the relative positions and orientations of two space structures from data on the angular positions and distances of fiducial objects on one structure as measured by a target tracking electronic camera and laser range finders on another structure. The program is written specifically for determining the relative alignments of two antennas, connected by a long truss, deployed in outer space from a space shuttle. The program is based partly on transformations among the various coordinate systems involved in the measurements and on a nonlinear mathematical model of vibrations of the truss. The program implements a Kalman filter that blends the measurement data with data from the model. Using time series of measurement data from the tracking camera and range finders, the program generates time series of data on the relative position and orientation of the antennas. A similar program described in a prior NASA Tech Briefs article was used onboard for monitoring the structures during flight. The present program is more precise and designed for use on Earth in post-flight processing of the measurement data to enable correction, for antenna motions, of scientific data acquired by use of the antennas.

  13. CMsearch: simultaneous exploration of protein sequence space and structure space improves not only protein homology detection but also protein structure prediction.

    PubMed

    Cui, Xuefeng; Lu, Zhiwu; Wang, Sheng; Jing-Yan Wang, Jim; Gao, Xin

    2016-06-15

    Protein homology detection, a fundamental problem in computational biology, is an indispensable step toward predicting protein structures and understanding protein functions. Despite the advances in recent decades on sequence alignment, threading and alignment-free methods, protein homology detection remains a challenging open problem. Recently, network methods that try to find transitive paths in the protein structure space demonstrate the importance of incorporating network information of the structure space. Yet, current methods merge the sequence space and the structure space into a single space, and thus introduce inconsistency in combining different sources of information. We present a novel network-based protein homology detection method, CMsearch, based on cross-modal learning. Instead of exploring a single network built from the mixture of sequence and structure space information, CMsearch builds two separate networks to represent the sequence space and the structure space. It then learns sequence-structure correlation by simultaneously taking sequence information, structure information, sequence space information and structure space information into consideration. We tested CMsearch on two challenging tasks, protein homology detection and protein structure prediction, by querying all 8332 PDB40 proteins. Our results demonstrate that CMsearch is insensitive to the similarity metrics used to define the sequence and the structure spaces. By using HMM-HMM alignment as the sequence similarity metric, CMsearch clearly outperforms state-of-the-art homology detection methods and the CASP-winning template-based protein structure prediction methods. Our program is freely available for download from http://sfb.kaust.edu.sa/Pages/Software.aspx : xin.gao@kaust.edu.sa Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  14. Transplant organizational structures: viewpoints from established centers.

    PubMed

    Abouljoud, M; Klintmalm, G; Whitehouse, S

    2012-10-01

    This personal viewpoint report summarizes the responses of a survey targeting established transplant programs with a structured framework, such as center, institute, or department, and stability of leadership to assure valuable experiential observations. The 18-item survey was sent to 20 US institutions that met inclusion criteria. The response rate was 100%. Seventeen institutions had a distinct transplant governance structure. A majority of respondents perceived that their type of transplant structure was associated with enhanced recognition within their institution (85%), improved regulatory compliance (85%), transplant volume growth (75%), improved quality outcomes (75%) and increased funding for transplant-related research (75%). The prevailing themes in respondents' remarks were the perceived need for autonomy of the transplant entity, alignment among services and finances and alignment of authority with responsibility. Many respondents suggested that a dialogue be opened about effective transplant infrastructure that overcomes the boundaries of traditional academic department silos. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

  15. Automated tilt series alignment and tomographic reconstruction in IMOD.

    PubMed

    Mastronarde, David N; Held, Susannah R

    2017-02-01

    Automated tomographic reconstruction is now possible in the IMOD software package, including the merging of tomograms taken around two orthogonal axes. Several developments enable the production of high-quality tomograms. When using fiducial markers for alignment, the markers to be tracked through the series are chosen automatically; if there is an excess of markers available, a well-distributed subset is selected that is most likely to track well. Marker positions are refined by applying an edge-enhancing Sobel filter, which results in a 20% improvement in alignment error for plastic-embedded samples and 10% for frozen-hydrated samples. Robust fitting, in which outlying points are given less or no weight in computing the fitting error, is used to obtain an alignment solution, so that aberrant points from the automated tracking can have little effect on the alignment. When merging two dual-axis tomograms, the alignment between them is refined from correlations between local patches; a measure of structure was developed so that patches with insufficient structure to give accurate correlations can now be excluded automatically. We have also developed a script for running all steps in the reconstruction process with a flexible mechanism for setting parameters, and we have added a user interface for batch processing of tilt series to the Etomo program in IMOD. Batch processing is fully compatible with interactive processing and can increase efficiency even when the automation is not fully successful, because users can focus their effort on the steps that require manual intervention. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. R3D-2-MSA: the RNA 3D structure-to-multiple sequence alignment server.

    PubMed

    Cannone, Jamie J; Sweeney, Blake A; Petrov, Anton I; Gutell, Robin R; Zirbel, Craig L; Leontis, Neocles

    2015-07-01

    The RNA 3D Structure-to-Multiple Sequence Alignment Server (R3D-2-MSA) is a new web service that seamlessly links RNA three-dimensional (3D) structures to high-quality RNA multiple sequence alignments (MSAs) from diverse biological sources. In this first release, R3D-2-MSA provides manual and programmatic access to curated, representative ribosomal RNA sequence alignments from bacterial, archaeal, eukaryal and organellar ribosomes, using nucleotide numbers from representative atomic-resolution 3D structures. A web-based front end is available for manual entry and an Application Program Interface for programmatic access. Users can specify up to five ranges of nucleotides and 50 nucleotide positions per range. The R3D-2-MSA server maps these ranges to the appropriate columns of the corresponding MSA and returns the contents of the columns, either for display in a web browser or in JSON format for subsequent programmatic use. The browser output page provides a 3D interactive display of the query, a full list of sequence variants with taxonomic information and a statistical summary of distinct sequence variants found. The output can be filtered and sorted in the browser. Previous user queries can be viewed at any time by resubmitting the output URL, which encodes the search and re-generates the results. The service is freely available with no login requirement at http://rna.bgsu.edu/r3d-2-msa. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Fast single-pass alignment and variant calling using sequencing data

    USDA-ARS?s Scientific Manuscript database

    Sequencing research requires efficient computation. Few programs use already known information about DNA variants when aligning sequence data to the reference map. New program findmap.f90 reads the previous variant list before aligning sequence, calling variant alleles, and summing the allele counts...

  18. MACSIMS : multiple alignment of complete sequences information management system

    PubMed Central

    Thompson, Julie D; Muller, Arnaud; Waterhouse, Andrew; Procter, Jim; Barton, Geoffrey J; Plewniak, Frédéric; Poch, Olivier

    2006-01-01

    Background In the post-genomic era, systems-level studies are being performed that seek to explain complex biological systems by integrating diverse resources from fields such as genomics, proteomics or transcriptomics. New information management systems are now needed for the collection, validation and analysis of the vast amount of heterogeneous data available. Multiple alignments of complete sequences provide an ideal environment for the integration of this information in the context of the protein family. Results MACSIMS is a multiple alignment-based information management program that combines the advantages of both knowledge-based and ab initio sequence analysis methods. Structural and functional information is retrieved automatically from the public databases. In the multiple alignment, homologous regions are identified and the retrieved data is evaluated and propagated from known to unknown sequences with these reliable regions. In a large-scale evaluation, the specificity of the propagated sequence features is estimated to be >99%, i.e. very few false positive predictions are made. MACSIMS is then used to characterise mutations in a test set of 100 proteins that are known to be involved in human genetic diseases. The number of sequence features associated with these proteins was increased by 60%, compared to the features available in the public databases. An XML format output file allows automatic parsing of the MACSIM results, while a graphical display using the JalView program allows manual analysis. Conclusion MACSIMS is a new information management system that incorporates detailed analyses of protein families at the structural, functional and evolutionary levels. MACSIMS thus provides a unique environment that facilitates knowledge extraction and the presentation of the most pertinent information to the biologist. A web server and the source code are available at . PMID:16792820

  19. Reliability of lower limb alignment measures using an established landmark-based method with a customized computer software program

    PubMed Central

    Sled, Elizabeth A.; Sheehy, Lisa M.; Felson, David T.; Costigan, Patrick A.; Lam, Miu; Cooke, T. Derek V.

    2010-01-01

    The objective of the study was to evaluate the reliability of frontal plane lower limb alignment measures using a landmark-based method by (1) comparing inter- and intra-reader reliability between measurements of alignment obtained manually with those using a computer program, and (2) determining inter- and intra-reader reliability of computer-assisted alignment measures from full-limb radiographs. An established method for measuring alignment was used, involving selection of 10 femoral and tibial bone landmarks. 1) To compare manual and computer methods, we used digital images and matching paper copies of five alignment patterns simulating healthy and malaligned limbs drawn using AutoCAD. Seven readers were trained in each system. Paper copies were measured manually and repeat measurements were performed daily for 3 days, followed by a similar routine with the digital images using the computer. 2) To examine the reliability of computer-assisted measures from full-limb radiographs, 100 images (200 limbs) were selected as a random sample from 1,500 full-limb digital radiographs which were part of the Multicenter Osteoarthritis (MOST) Study. Three trained readers used the software program to measure alignment twice from the batch of 100 images, with two or more weeks between batch handling. Manual and computer measures of alignment showed excellent agreement (intraclass correlations [ICCs] 0.977 – 0.999 for computer analysis; 0.820 – 0.995 for manual measures). The computer program applied to full-limb radiographs produced alignment measurements with high inter- and intra-reader reliability (ICCs 0.839 – 0.998). In conclusion, alignment measures using a bone landmark-based approach and a computer program were highly reliable between multiple readers. PMID:19882339

  20. Automatic classification of protein structures relying on similarities between alignments

    PubMed Central

    2012-01-01

    Background Identification of protein structural cores requires isolation of sets of proteins all sharing a same subset of structural motifs. In the context of an ever growing number of available 3D protein structures, standard and automatic clustering algorithms require adaptations so as to allow for efficient identification of such sets of proteins. Results When considering a pair of 3D structures, they are stated as similar or not according to the local similarities of their matching substructures in a structural alignment. This binary relation can be represented in a graph of similarities where a node represents a 3D protein structure and an edge states that two 3D protein structures are similar. Therefore, classifying proteins into structural families can be viewed as a graph clustering task. Unfortunately, because such a graph encodes only pairwise similarity information, clustering algorithms may include in the same cluster a subset of 3D structures that do not share a common substructure. In order to overcome this drawback we first define a ternary similarity on a triple of 3D structures as a constraint to be satisfied by the graph of similarities. Such a ternary constraint takes into account similarities between pairwise alignments, so as to ensure that the three involved protein structures do have some common substructure. We propose hereunder a modification algorithm that eliminates edges from the original graph of similarities and gives a reduced graph in which no ternary constraints are violated. Our approach is then first to build a graph of similarities, then to reduce the graph according to the modification algorithm, and finally to apply to the reduced graph a standard graph clustering algorithm. Such method was used for classifying ASTRAL-40 non-redundant protein domains, identifying significant pairwise similarities with Yakusa, a program devised for rapid 3D structure alignments. Conclusions We show that filtering similarities prior to standard graph based clustering process by applying ternary similarity constraints i) improves the separation of proteins of different classes and consequently ii) improves the classification quality of standard graph based clustering algorithms according to the reference classification SCOP. PMID:22974051

  1. BAYESIAN PROTEIN STRUCTURE ALIGNMENT.

    PubMed

    Rodriguez, Abel; Schmidler, Scott C

    The analysis of the three-dimensional structure of proteins is an important topic in molecular biochemistry. Structure plays a critical role in defining the function of proteins and is more strongly conserved than amino acid sequence over evolutionary timescales. A key challenge is the identification and evaluation of structural similarity between proteins; such analysis can aid in understanding the role of newly discovered proteins and help elucidate evolutionary relationships between organisms. Computational biologists have developed many clever algorithmic techniques for comparing protein structures, however, all are based on heuristic optimization criteria, making statistical interpretation somewhat difficult. Here we present a fully probabilistic framework for pairwise structural alignment of proteins. Our approach has several advantages, including the ability to capture alignment uncertainty and to estimate key "gap" parameters which critically affect the quality of the alignment. We show that several existing alignment methods arise as maximum a posteriori estimates under specific choices of prior distributions and error models. Our probabilistic framework is also easily extended to incorporate additional information, which we demonstrate by including primary sequence information to generate simultaneous sequence-structure alignments that can resolve ambiguities obtained using structure alone. This combined model also provides a natural approach for the difficult task of estimating evolutionary distance based on structural alignments. The model is illustrated by comparison with well-established methods on several challenging protein alignment examples.

  2. 42 CFR 435.1205 - Alignment with exchange initial open enrollment period.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Alignment with exchange initial open enrollment... Between Medicaid, CHIP, Exchanges and Other Insurance Affordability Programs § 435.1205 Alignment with... electronic interface, an electronic account transferred from another insurance affordability program. (2) For...

  3. 3D-QSAR and docking studies on 4-anilinoquinazoline and 4-anilinoquinoline epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors

    NASA Astrophysics Data System (ADS)

    Assefa, Haregewein; Kamath, Shantaram; Buolamwini, John K.

    2003-08-01

    The overexpression and/or mutation of the epidermal growth factor receptor (EGFR) tyrosine kinase has been observed in many human solid tumors, and is under intense investigation as a novel anticancer molecular target. Comparative 3D-QSAR analyses using different alignments were undertaken employing comparative molecular field analysis (CoMFA) and comparative molecular similarity analysis (CoMSIA) for 122 anilinoquinazoline and 50 anilinoquinoline inhibitors of EGFR kinase. The SYBYL multifit alignment rule was applied to three different conformational templates, two obtained from a MacroModel Monte Carlo conformational search, and one from the bound conformation of erlotinib in complex with EGFR in the X-ray crystal structure. In addition, a flexible ligand docking alignment obtained with the GOLD docking program, and a novel flexible receptor-guided consensus dynamics alignment obtained with the DISCOVER program in the INSIGHTII modeling package were also investigated. 3D-QSAR models with q2 values up to 0.70 and r2 values up to 0.97 were obtained. Among the 4-anilinoquinazoline set, the q2 values were similar, but the ability of the different conformational models to predict the activities of an external test set varied considerably. In this regard, the model derived using the X-ray crystallographically determined bioactive conformation of erlotinib afforded the best predictive model. Electrostatic, hydrophobic and H-bond donor descriptors contributed the most to the QSAR models of the 4-anilinoquinazolines, whereas electrostatic, hydrophobic and H-bond acceptor descriptors contributed the most to the 4-anilinoquinoline QSAR, particularly the H-bond acceptor descriptor. A novel receptor-guided consensus dynamics alignment has also been introduced for 3D-QSAR studies. This new alignment method may incorporate to some extent ligand-receptor induced fit effects into 3D-QSAR models.

  4. Spreadsheet-based program for alignment of overlapping DNA sequences.

    PubMed

    Anbazhagan, R; Gabrielson, E

    1999-06-01

    Molecular biology laboratories frequently face the challenge of aligning small overlapping DNA sequences derived from a long DNA segment. Here, we present a short program that can be used to adapt Excel spreadsheets as a tool for aligning DNA sequences, regardless of their orientation. The program runs on any Windows or Macintosh operating system computer with Excel 97 or Excel 98. The program is available for use as an Excel file, which can be downloaded from the BioTechniques Web site. Upon execution, the program opens a specially designed customized workbook and is capable of identifying overlapping regions between two sequence fragments and displaying the sequence alignment. It also performs a number of specialized functions such as recognition of restriction enzyme cutting sites and CpG island mapping without costly specialized software.

  5. Simultaneous phylogeny reconstruction and multiple sequence alignment

    PubMed Central

    Yue, Feng; Shi, Jian; Tang, Jijun

    2009-01-01

    Background A phylogeny is the evolutionary history of a group of organisms. To date, sequence data is still the most used data type for phylogenetic reconstruction. Before any sequences can be used for phylogeny reconstruction, they must be aligned, and the quality of the multiple sequence alignment has been shown to affect the quality of the inferred phylogeny. At the same time, all the current multiple sequence alignment programs use a guide tree to produce the alignment and experiments showed that good guide trees can significantly improve the multiple alignment quality. Results We devise a new algorithm to simultaneously align multiple sequences and search for the phylogenetic tree that leads to the best alignment. We also implemented the algorithm as a C program package, which can handle both DNA and protein data and can take simple cost model as well as complex substitution matrices, such as PAM250 or BLOSUM62. The performance of the new method are compared with those from other popular multiple sequence alignment tools, including the widely used programs such as ClustalW and T-Coffee. Experimental results suggest that this method has good performance in terms of both phylogeny accuracy and alignment quality. Conclusion We present an algorithm to align multiple sequences and reconstruct the phylogenies that minimize the alignment score, which is based on an efficient algorithm to solve the median problems for three sequences. Our extensive experiments suggest that this method is very promising and can produce high quality phylogenies and alignments. PMID:19208110

  6. Clustalnet: the joining of Clustal and CORBA.

    PubMed

    Campagne, F

    2000-07-01

    Performing sequence alignment operations from a different program than the original sequence alignment code, and/or through a network connection, is often required. Interactive alignment editors and large-scale biological data analysis are common examples where such a flexibility is important. Interoperability between the alignment engine and the client should be obtained regardless of the architectures and programming languages of the server and client. Clustalnet, a Clustal alignment CORBA server is described, which was developed on the basis of Clustalw. This server brings the robustness of the algorithms and implementations of Clustal to a new level of reuse. A Clustalnet server object can be accessed from a program, transparently through the network. We present interfaces to perform the alignment operations and to control these operations via immutable contexts. The interfaces that select the contexts do not depend on the nature of the operation to be performed, making the design modular. The IDL interfaces presented here are not specific to Clustal and can be implemented on top of different sequence alignment algorithm implementations.

  7. Sketch on the structural geology and vulcanism in the Central High Plateau of the Bolivian Andes

    NASA Technical Reports Server (NTRS)

    Brockmann, C. E. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. The Earth Resources Technology Satellite Program has as an objective the development of tectonic maps for Bolivia. Maps were prepared using the images of ERTS-1 in a preliminary study of alignments observed and rapidly interpreted in images 1010-14033-3-4-5-6-7 on a scale of 1:1,000,000, and later verified on the ground with corresponding fault zones. This information was not shown on existing geologial maps. The ERTS-1 imagery was used in volcanology research for drawing the regional limits of volcanic formations as soon as the alignment and the extent of the volcanoes could be determined. The extensive coverage of ERTS-1 images provides an excellent opportunity for developing studies of regional structures.

  8. Iterative non-sequential protein structural alignment.

    PubMed

    Salem, Saeed; Zaki, Mohammed J; Bystroff, Christopher

    2009-06-01

    Structural similarity between proteins gives us insights into their evolutionary relationships when there is low sequence similarity. In this paper, we present a novel approach called SNAP for non-sequential pair-wise structural alignment. Starting from an initial alignment, our approach iterates over a two-step process consisting of a superposition step and an alignment step, until convergence. We propose a novel greedy algorithm to construct both sequential and non-sequential alignments. The quality of SNAP alignments were assessed by comparing against the manually curated reference alignments in the challenging SISY and RIPC datasets. Moreover, when applied to a dataset of 4410 protein pairs selected from the CATH database, SNAP produced longer alignments with lower rmsd than several state-of-the-art alignment methods. Classification of folds using SNAP alignments was both highly sensitive and highly selective. The SNAP software along with the datasets are available online at http://www.cs.rpi.edu/~zaki/software/SNAP.

  9. Preference and Priority in Federal Funding: Aligning Federal Resources to Maximize Program Investment Efficiency and Impacts in Communities

    EPA Pesticide Factsheets

    This page contains the document, Preference and Priority in Federal Funding: Aligning Federal Resources to Maximize Program Investment Efficiency and Impacts in Communities - Lessons from EPA’s Brownfields Program.

  10. United States Air Force Summer Research Program 1991. Graduate Student Research Program (GSRP) Reports. Volume 9. Wright Laboratory

    DTIC Science & Technology

    1992-01-09

    Materials 22 Deply of Laminated Panels with Perforation due to Impact John Lair 23 Actuator Location and Optimal Control Design for Flexible Structures...procedure is the focusing and alignment of the UV souce. Though the output of a vapor lamp is nonuniform ., intensity peaks can be smoothed by expanding the...surface, localized surface heatig may occur. Secondly, the output of a mercury vapor lame is nonuniform , requiring diffusion tc obtain a more- uniform

  11. Using business intelligence to improve performance.

    PubMed

    Wadsworth, Tom; Graves, Brian; Glass, Steve; Harrison, A Marc; Donovan, Chris; Proctor, Andrew

    2009-10-01

    Cleveland Clinic's enterprise performance management program offers proof that comparisons of actual performance against strategic objectives can enable healthcare organization to achieve rapid organizational change. Here are four lessons Cleveland Clinic learned from this initiative: Align performance metrics with strategic initiatives. Structure dashboards for the CEO. Link performance to annual reviews. Customize dashboard views to the specific user.

  12. PASS2: an automated database of protein alignments organised as structural superfamilies.

    PubMed

    Bhaduri, Anirban; Pugalenthi, Ganesan; Sowdhamini, Ramanathan

    2004-04-02

    The functional selection and three-dimensional structural constraints of proteins in nature often relates to the retention of significant sequence similarity between proteins of similar fold and function despite poor sequence identity. Organization of structure-based sequence alignments for distantly related proteins, provides a map of the conserved and critical regions of the protein universe that is useful for the analysis of folding principles, for the evolutionary unification of protein families and for maximizing the information return from experimental structure determination. The Protein Alignment organised as Structural Superfamily (PASS2) database represents continuously updated, structural alignments for evolutionary related, sequentially distant proteins. An automated and updated version of PASS2 is, in direct correspondence with SCOP 1.63, consisting of sequences having identity below 40% among themselves. Protein domains have been grouped into 628 multi-member superfamilies and 566 single member superfamilies. Structure-based sequence alignments for the superfamilies have been obtained using COMPARER, while initial equivalencies have been derived from a preliminary superposition using LSQMAN or STAMP 4.0. The final sequence alignments have been annotated for structural features using JOY4.0. The database is supplemented with sequence relatives belonging to different genomes, conserved spatially interacting and structural motifs, probabilistic hidden markov models of superfamilies based on the alignments and useful links to other databases. Probabilistic models and sensitive position specific profiles obtained from reliable superfamily alignments aid annotation of remote homologues and are useful tools in structural and functional genomics. PASS2 presents the phylogeny of its members both based on sequence and structural dissimilarities. Clustering of members allows us to understand diversification of the family members. The search engine has been improved for simpler browsing of the database. The database resolves alignments among the structural domains consisting of evolutionarily diverged set of sequences. Availability of reliable sequence alignments of distantly related proteins despite poor sequence identity and single-member superfamilies permit better sampling of structures in libraries for fold recognition of new sequences and for the understanding of protein structure-function relationships of individual superfamilies. PASS2 is accessible at http://www.ncbs.res.in/~faculty/mini/campass/pass2.html

  13. Performance management models for public health: Public Health Accreditation Board/Baldrige connections, alignment, and distinctions.

    PubMed

    Gorenflo, Grace G; Klater, David M; Mason, Marlene; Russo, Pamela; Rivera, Lillian

    2014-01-01

    The nationally known Malcolm Baldrige Award for Excellence ("Baldrige program") recognizes outstanding performance management and is specifically cited by the Public Health Accreditation Board (PHAB) as a potential framework for PHAB's requisite performance management system. The authors developed a crosswalk that identifies alignments between the 2 programs and is a highlight of the Quest for Exceptional Performance tool that is intended to help health departments capitalize on the connections between the 2 programs. To provide deeper insight into the most robust connections between the 2 programs. The authors developed a crosswalk by listing the PHAB measures, identifying corresponding Baldrige areas to address, and assigning a rating regarding the strength of the alignment. Subsequently, they generated a matrix with numerical scores reflecting the strength of the PHAB-Baldrige alignments that were then analyzed for frequency and strength of alignment by PHAB domain and by Baldrige category. The tool developers and 3 public health leaders with experience in the Baldrige program contributed to both the design and the analyses. The measures used reflected both the frequency and strength of alignments. Of the 123 alignments identified in the crosswalk, 39 were rated as high, 40 as medium, and 44 as low. The strongest connections were in the areas of performance management, quality improvement, strategic planning, workforce development, assessment and analysis, and customer service. While the areas with the most frequent and strongest connections provide the most useful basis for health departments pursuing Baldrige recognition or using Baldrige criteria as a framework for performance management, all alignments could be considered for both purposes.

  14. Overcoming Sequence Misalignments with Weighted Structural Superposition

    PubMed Central

    Khazanov, Nickolay A.; Damm-Ganamet, Kelly L.; Quang, Daniel X.; Carlson, Heather A.

    2012-01-01

    An appropriate structural superposition identifies similarities and differences between homologous proteins that are not evident from sequence alignments alone. We have coupled our Gaussian-weighted RMSD (wRMSD) tool with a sequence aligner and seed extension (SE) algorithm to create a robust technique for overlaying structures and aligning sequences of homologous proteins (HwRMSD). HwRMSD overcomes errors in the initial sequence alignment that would normally propagate into a standard RMSD overlay. SE can generate a corrected sequence alignment from the improved structural superposition obtained by wRMSD. HwRMSD’s robust performance and its superiority over standard RMSD are demonstrated over a range of homologous proteins. Its better overlay results in corrected sequence alignments with good agreement to HOMSTRAD. Finally, HwRMSD is compared to established structural alignment methods: FATCAT, SSM, CE, and Dalilite. Most methods are comparable at placing residue pairs within 2 Å, but HwRMSD places many more residue pairs within 1 Å, providing a clear advantage. Such high accuracy is essential in drug design, where small distances can have a large impact on computational predictions. This level of accuracy is also needed to correct sequence alignments in an automated fashion, especially for omics-scale analysis. HwRMSD can align homologs with low sequence identity and large conformational differences, cases where both sequence-based and structural-based methods may fail. The HwRMSD pipeline overcomes the dependency of structural overlays on initial sequence pairing and removes the need to determine the best sequence-alignment method, substitution matrix, and gap parameters for each unique pair of homologs. PMID:22733542

  15. MollDE: a homology modeling framework you can click with.

    PubMed

    Canutescu, Adrian A; Dunbrack, Roland L

    2005-06-15

    Molecular Integrated Development Environment (MolIDE) is an integrated application designed to provide homology modeling tools and protocols under a uniform, user-friendly graphical interface. Its main purpose is to combine the most frequent modeling steps in a semi-automatic, interactive way, guiding the user from the target protein sequence to the final three-dimensional protein structure. The typical basic homology modeling process is composed of building sequence profiles of the target sequence family, secondary structure prediction, sequence alignment with PDB structures, assisted alignment editing, side-chain prediction and loop building. All of these steps are available through a graphical user interface. MolIDE's user-friendly and streamlined interactive modeling protocol allows the user to focus on the important modeling questions, hiding from the user the raw data generation and conversion steps. MolIDE was designed from the ground up as an open-source, cross-platform, extensible framework. This allows developers to integrate additional third-party programs to MolIDE. http://dunbrack.fccc.edu/molide/molide.php rl_dunbrack@fccc.edu.

  16. Large-Scale Structure of Subauroral Polarization Streams During the Main Phase of a Severe Geomagnetic Storm

    NASA Astrophysics Data System (ADS)

    He, Fei; Zhang, Xiao-Xin; Wang, Wenbin; Liu, Libo; Ren, Zhi-Peng; Yue, Xinan; Hu, Lianhuan; Wan, Weixing; Wang, Hui

    2018-04-01

    In this study, we present multisatellite observations of the large-scale structures of subauroral polarization streams (SAPS) during the main phase of a severe geomagnetic storm that occurred on 31 March 2001. Observations by the Defense Meteorological Satellite Program F12 to F15 satellites indicate that the SAPS were first generated around the dusk sector at the beginning of the main phase. The SAPS channel then expanded toward the midnight sector and moved to lower latitudes as the main phase progressed. The peak velocity, latitudinal width, latitudinal alignment, and longitudinal span of the SAPS channel were highly dynamic during the storm main phase. The large westward velocities of the SAPS were located in the region of low electron densities, associated with low ionospheric conductivity. The large-scale structures of the SAPS also corresponded closely to those of the region-2 field-aligned currents, which were mainly determined by the azimuthal pressure gradient of the ring current.

  17. GIRAF: a method for fast search and flexible alignment of ligand binding interfaces in proteins at atomic resolution

    PubMed Central

    Kinjo, Akira R.; Nakamura, Haruki

    2012-01-01

    Comparison and classification of protein structures are fundamental means to understand protein functions. Due to the computational difficulty and the ever-increasing amount of structural data, however, it is in general not feasible to perform exhaustive all-against-all structure comparisons necessary for comprehensive classifications. To efficiently handle such situations, we have previously proposed a method, now called GIRAF. We herein describe further improvements in the GIRAF protein structure search and alignment method. The GIRAF method achieves extremely efficient search of similar structures of ligand binding sites of proteins by exploiting database indexing of structural features of local coordinate frames. In addition, it produces refined atom-wise alignments by iterative applications of the Hungarian method to the bipartite graph defined for a pair of superimposed structures. By combining the refined alignments based on different local coordinate frames, it is made possible to align structures involving domain movements. We provide detailed accounts for the database design, the search and alignment algorithms as well as some benchmark results. PMID:27493524

  18. Web-Beagle: a web server for the alignment of RNA secondary structures.

    PubMed

    Mattei, Eugenio; Pietrosanto, Marco; Ferrè, Fabrizio; Helmer-Citterich, Manuela

    2015-07-01

    Web-Beagle (http://beagle.bio.uniroma2.it) is a web server for the pairwise global or local alignment of RNA secondary structures. The server exploits a new encoding for RNA secondary structure and a substitution matrix of RNA structural elements to perform RNA structural alignments. The web server allows the user to compute up to 10 000 alignments in a single run, taking as input sets of RNA sequences and structures or primary sequences alone. In the latter case, the server computes the secondary structure prediction for the RNAs on-the-fly using RNAfold (free energy minimization). The user can also compare a set of input RNAs to one of five pre-compiled RNA datasets including lncRNAs and 3' UTRs. All types of comparison produce in output the pairwise alignments along with structural similarity and statistical significance measures for each resulting alignment. A graphical color-coded representation of the alignments allows the user to easily identify structural similarities between RNAs. Web-Beagle can be used for finding structurally related regions in two or more RNAs, for the identification of homologous regions or for functional annotation. Benchmark tests show that Web-Beagle has lower computational complexity, running time and better performances than other available methods. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. GeneBee-net: Internet-based server for analyzing biopolymers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brodsky, L.I.; Ivanov, V.V.; Nikolaev, V.K.

    This work describes a network server for searching databanks of biopolymer structures and performing other biocomputing procedures; it is available via direct Internet connection. Basic server procedures are dedicated to homology (similarity) search of sequence and 3D structure of proteins. The homologies found could be used to build multiple alignments, predict protein and RNA secondary structure, and construct phylogenetic trees. In addition to traditional methods of sequence similarity search, the authors propose {open_quotes}non-matrix{close_quotes} (correlational) search. An analogous approach is used to identify regions of similar tertiary structure of proteins. Algorithm concepts and usage examples are presented for new methods. Servicemore » logic is based upon interaction of a client program and server procedures. The client program allows the compilation of queries and the processing of results of an analysis.« less

  20. Transformation and Alignment in Similarity

    ERIC Educational Resources Information Center

    Hodgetts, Carl J.; Hahn, Ulrike; Chater, Nick

    2009-01-01

    This paper contrasts two structural accounts of psychological similarity: structural alignment (SA) and Representational Distortion (RD). SA proposes that similarity is determined by how readily the structures of two objects can be brought into alignment; RD measures similarity by the complexity of the transformation that "distorts" one…

  1. National Dam Safety Program. Structure F-1 (MO 20512), Verdigris - Neosho River Basin, Newton County, Missouri. Phase I Inspection Report.

    DTIC Science & Technology

    1980-08-01

    soil series. These soils generally make good fill material when properly compacted. The "Geologic Map ot Missouri" indicates that two known faults run in...appurtenant structures, reser- voir, and downstream features are presented in Appendix D. B. Dam: The dam appears to be in good condition. No sloughing...or sliding of the embankment was noted. The horizontal and vertical alignments of the crest were good , and no surfacing cracking or unusual movement

  2. Realigning Shared Governance With Magnet® and the Organization's Operating System to Achieve Clinical Excellence.

    PubMed

    Moreno, Janette V; Girard, Anita S; Foad, Wendy

    2018-03-01

    In 2012, an academic medical center successfully overhauled a 15-year-old shared governance to align 6 house-wide and 30 unit-based councils with the new Magnet Recognition Program® and the organization's operating system, using the processes of LEAN methodology. The redesign improved cross-council communication structures, facilitated effective shared decision-making processes, increased staff engagement, and improved clinical outcomes. The innovative structural and process elements of the new model are replicable in other health institutions.

  3. Vertically aligned nanostructure scanning probe microscope tips

    DOEpatents

    Guillorn, Michael A.; Ilic, Bojan; Melechko, Anatoli V.; Merkulov, Vladimir I.; Lowndes, Douglas H.; Simpson, Michael L.

    2006-12-19

    Methods and apparatus are described for cantilever structures that include a vertically aligned nanostructure, especially vertically aligned carbon nanofiber scanning probe microscope tips. An apparatus includes a cantilever structure including a substrate including a cantilever body, that optionally includes a doped layer, and a vertically aligned nanostructure coupled to the cantilever body.

  4. Application of the MAFFT sequence alignment program to large data—reexamination of the usefulness of chained guide trees

    PubMed Central

    Yamada, Kazunori D.; Tomii, Kentaro; Katoh, Kazutaka

    2016-01-01

    Motivation: Large multiple sequence alignments (MSAs), consisting of thousands of sequences, are becoming more and more common, due to advances in sequencing technologies. The MAFFT MSA program has several options for building large MSAs, but their performances have not been sufficiently assessed yet, because realistic benchmarking of large MSAs has been difficult. Recently, such assessments have been made possible through the HomFam and ContTest benchmark protein datasets. Along with the development of these datasets, an interesting theory was proposed: chained guide trees increase the accuracy of MSAs of structurally conserved regions. This theory challenges the basis of progressive alignment methods and needs to be examined by being compared with other known methods including computationally intensive ones. Results: We used HomFam, ContTest and OXFam (an extended version of OXBench) to evaluate several methods enabled in MAFFT: (1) a progressive method with approximate guide trees, (2) a progressive method with chained guide trees, (3) a combination of an iterative refinement method and a progressive method and (4) a less approximate progressive method that uses a rigorous guide tree and consistency score. Other programs, Clustal Omega and UPP, available for large MSAs, were also included into the comparison. The effect of method 2 (chained guide trees) was positive in ContTest but negative in HomFam and OXFam. Methods 3 and 4 increased the benchmark scores more consistently than method 2 for the three datasets, suggesting that they are safer to use. Availability and Implementation: http://mafft.cbrc.jp/alignment/software/ Contact: katoh@ifrec.osaka-u.ac.jp Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27378296

  5. Optimizing multiple sequence alignments using a genetic algorithm based on three objectives: structural information, non-gaps percentage and totally conserved columns.

    PubMed

    Ortuño, Francisco M; Valenzuela, Olga; Rojas, Fernando; Pomares, Hector; Florido, Javier P; Urquiza, Jose M; Rojas, Ignacio

    2013-09-01

    Multiple sequence alignments (MSAs) are widely used approaches in bioinformatics to carry out other tasks such as structure predictions, biological function analyses or phylogenetic modeling. However, current tools usually provide partially optimal alignments, as each one is focused on specific biological features. Thus, the same set of sequences can produce different alignments, above all when sequences are less similar. Consequently, researchers and biologists do not agree about which is the most suitable way to evaluate MSAs. Recent evaluations tend to use more complex scores including further biological features. Among them, 3D structures are increasingly being used to evaluate alignments. Because structures are more conserved in proteins than sequences, scores with structural information are better suited to evaluate more distant relationships between sequences. The proposed multiobjective algorithm, based on the non-dominated sorting genetic algorithm, aims to jointly optimize three objectives: STRIKE score, non-gaps percentage and totally conserved columns. It was significantly assessed on the BAliBASE benchmark according to the Kruskal-Wallis test (P < 0.01). This algorithm also outperforms other aligners, such as ClustalW, Multiple Sequence Alignment Genetic Algorithm (MSA-GA), PRRP, DIALIGN, Hidden Markov Model Training (HMMT), Pattern-Induced Multi-sequence Alignment (PIMA), MULTIALIGN, Sequence Alignment Genetic Algorithm (SAGA), PILEUP, Rubber Band Technique Genetic Algorithm (RBT-GA) and Vertical Decomposition Genetic Algorithm (VDGA), according to the Wilcoxon signed-rank test (P < 0.05), whereas it shows results not significantly different to 3D-COFFEE (P > 0.05) with the advantage of being able to use less structures. Structural information is included within the objective function to evaluate more accurately the obtained alignments. The source code is available at http://www.ugr.es/~fortuno/MOSAStrE/MO-SAStrE.zip.

  6. REPPER—repeats and their periodicities in fibrous proteins

    PubMed Central

    Gruber, Markus; Söding, Johannes; Lupas, Andrei N.

    2005-01-01

    REPPER (REPeats and their PERiodicities) is an integrated server that detects and analyzes regions with short gapless repeats in protein sequences or alignments. It finds periodicities by Fourier Transform (FTwin) and internal similarity analysis (REPwin). FTwin assigns numerical values to amino acids that reflect certain properties, for instance hydrophobicity, and gives information on corresponding periodicities. REPwin uses self-alignments and displays repeats that reveal significant internal similarities. Both programs use a sliding window to ensure that different periodic regions within the same protein are detected independently. FTwin and REPwin are complemented by secondary structure prediction (PSIPRED) and coiled coil prediction (COILS), making the server a versatile analysis tool for sequences of fibrous proteins. REPPER is available at . PMID:15980460

  7. The Impact of a "Framework"-Aligned Science Professional Development Program on Literacy and Mathematics Achievement of K-3 Students

    ERIC Educational Resources Information Center

    Paprzycki, Peter; Tuttle, Nicole; Czerniak, Charlene M.; Molitor, Scott; Kadervaek, Joan; Mendenhall, Robert

    2017-01-01

    This study investigates the effect of a Framework-aligned professional development program at the PreK-3 level. The NSF funded program integrated science with literacy and mathematics learning and provided teacher professional development, along with materials and programming for parents to encourage science investigations and discourse around…

  8. Statistical potential-based amino acid similarity matrices for aligning distantly related protein sequences.

    PubMed

    Tan, Yen Hock; Huang, He; Kihara, Daisuke

    2006-08-15

    Aligning distantly related protein sequences is a long-standing problem in bioinformatics, and a key for successful protein structure prediction. Its importance is increasing recently in the context of structural genomics projects because more and more experimentally solved structures are available as templates for protein structure modeling. Toward this end, recent structure prediction methods employ profile-profile alignments, and various ways of aligning two profiles have been developed. More fundamentally, a better amino acid similarity matrix can improve a profile itself; thereby resulting in more accurate profile-profile alignments. Here we have developed novel amino acid similarity matrices from knowledge-based amino acid contact potentials. Contact potentials are used because the contact propensity to the other amino acids would be one of the most conserved features of each position of a protein structure. The derived amino acid similarity matrices are tested on benchmark alignments at three different levels, namely, the family, the superfamily, and the fold level. Compared to BLOSUM45 and the other existing matrices, the contact potential-based matrices perform comparably in the family level alignments, but clearly outperform in the fold level alignments. The contact potential-based matrices perform even better when suboptimal alignments are considered. Comparing the matrices themselves with each other revealed that the contact potential-based matrices are very different from BLOSUM45 and the other matrices, indicating that they are located in a different basin in the amino acid similarity matrix space.

  9. Multiple sequence alignment in HTML: colored, possibly hyperlinked, compact representations.

    PubMed

    Campagne, F; Maigret, B

    1998-02-01

    Protein sequence alignments are widely used in protein structure prediction, protein engineering, modeling of proteins, etc. This type of representation is useful at different stages of scientific activity: looking at previous results, working on a research project, and presenting the results. There is a need to make it available through a network (intranet or WWW), in a way that allows biologists, chemists, and noncomputer specialists to look at the data and carry on research--possibly in a collaborative research. Previous methods (text-based, Java-based) are reported and their advantages are discussed. We have developed two novel approaches to represent the alignments as colored, hyper-linked HTML pages. The first method creates an HTML page that uses efficiently the image cache mechanism of a WWW browser, thereby allowing the user to browse different alignments without waiting for the images to be loaded through the network, but only for the first viewed alignment. The generated pages can be browsed with any HTML2.0-compliant browser. The second method that we propose uses W3C-CSS1-style sheets to render alignments. This new method generates pages that require recent browsers to be viewed. We implemented these methods in the Viseur program and made a WWW service available that allows a user to convert an MSF alignment file in HTML for WWW publishing. The latter service is available at http:@www.lctn.u-nancy.fr/viseur/services.htm l.

  10. Sequence alignment visualization in HTML5 without Java.

    PubMed

    Gille, Christoph; Birgit, Weyand; Gille, Andreas

    2014-01-01

    Java has been extensively used for the visualization of biological data in the web. However, the Java runtime environment is an additional layer of software with an own set of technical problems and security risks. HTML in its new version 5 provides features that for some tasks may render Java unnecessary. Alignment-To-HTML is the first HTML-based interactive visualization for annotated multiple sequence alignments. The server side script interpreter can perform all tasks like (i) sequence retrieval, (ii) alignment computation, (iii) rendering, (iv) identification of a homologous structural models and (v) communication with BioDAS-servers. The rendered alignment can be included in web pages and is displayed in all browsers on all platforms including touch screen tablets. The functionality of the user interface is similar to legacy Java applets and includes color schemes, highlighting of conserved and variable alignment positions, row reordering by drag and drop, interlinked 3D visualization and sequence groups. Novel features are (i) support for multiple overlapping residue annotations, such as chemical modifications, single nucleotide polymorphisms and mutations, (ii) mechanisms to quickly hide residue annotations, (iii) export to MS-Word and (iv) sequence icons. Alignment-To-HTML, the first interactive alignment visualization that runs in web browsers without additional software, confirms that to some extend HTML5 is already sufficient to display complex biological data. The low speed at which programs are executed in browsers is still the main obstacle. Nevertheless, we envision an increased use of HTML and JavaScript for interactive biological software. Under GPL at: http://www.bioinformatics.org/strap/toHTML/.

  11. MultiSETTER: web server for multiple RNA structure comparison.

    PubMed

    Čech, Petr; Hoksza, David; Svozil, Daniel

    2015-08-12

    Understanding the architecture and function of RNA molecules requires methods for comparing and analyzing their tertiary and quaternary structures. While structural superposition of short RNAs is achievable in a reasonable time, large structures represent much bigger challenge. Therefore, we have developed a fast and accurate algorithm for RNA pairwise structure superposition called SETTER and implemented it in the SETTER web server. However, though biological relationships can be inferred by a pairwise structure alignment, key features preserved by evolution can be identified only from a multiple structure alignment. Thus, we extended the SETTER algorithm to the alignment of multiple RNA structures and developed the MultiSETTER algorithm. In this paper, we present the updated version of the SETTER web server that implements a user friendly interface to the MultiSETTER algorithm. The server accepts RNA structures either as the list of PDB IDs or as user-defined PDB files. After the superposition is computed, structures are visualized in 3D and several reports and statistics are generated. To the best of our knowledge, the MultiSETTER web server is the first publicly available tool for a multiple RNA structure alignment. The MultiSETTER server offers the visual inspection of an alignment in 3D space which may reveal structural and functional relationships not captured by other multiple alignment methods based either on a sequence or on secondary structure motifs.

  12. Aligning Accreditation and Academic Program Reviews: A Canadian Case Study

    ERIC Educational Resources Information Center

    Bowker, Lynne

    2017-01-01

    Purpose: This paper aims to investigate the potential benefits and limitations associated with aligning accreditation and academic program reviews in post-secondary institutions, using a descriptive case study approach. Design/methodology/approach: The paper describes two Canadian graduate programs that are subject to both external professional…

  13. "Working to shape what society's expectations of us should be": Philip Morris' societal alignment strategy.

    PubMed

    Yang, J S; Malone, R E

    2008-12-01

    A key element of Philip Morris's (PM's) corporate social responsibility initiatives is "societal alignment", defined as "strategies and programs to meet society's expectations of a responsible tobacco company". This study explored the genesis and implementation of Philip Morris' (PM) societal alignment efforts. The study retrieved and analysed approximately 375 previously undisclosed PM documents now available electronically. Using an iterative process, the study categorised themes and prepared a case analysis. Beginning in 1999, PM sought to become "societally aligned" by identifying expectations of a responsible tobacco company through public opinion research and developing and publicising programs to meet those expectations. Societal alignment was undertaken within the US and globally to ensure an environment favourable to PM's business objectives. Despite PM's claims to be "changing", however, societal alignment in practice was highly selective. PM responded to public "expectations" largely by retooling existing positions and programs, while entirely ignoring other expectations that might have interfered with its business goals. It also appears that convincing employees of the value and authenticity of societal alignment was difficult. As implementation of the Framework Convention on Tobacco Control proceeds, tobacco control advocates should closely monitor development of such "alignment" initiatives and expose the motivations and contradictions they reveal.

  14. Algorithms for Automatic Alignment of Arrays

    NASA Technical Reports Server (NTRS)

    Chatterjee, Siddhartha; Gilbert, John R.; Oliker, Leonid; Schreiber, Robert; Sheffler, Thomas J.

    1996-01-01

    Aggregate data objects (such as arrays) are distributed across the processor memories when compiling a data-parallel language for a distributed-memory machine. The mapping determines the amount of communication needed to bring operands of parallel operations into alignment with each other. A common approach is to break the mapping into two stages: an alignment that maps all the objects to an abstract template, followed by a distribution that maps the template to the processors. This paper describes algorithms for solving the various facets of the alignment problem: axis and stride alignment, static and mobile offset alignment, and replication labeling. We show that optimal axis and stride alignment is NP-complete for general program graphs, and give a heuristic method that can explore the space of possible solutions in a number of ways. We show that some of these strategies can give better solutions than a simple greedy approach proposed earlier. We also show how local graph contractions can reduce the size of the problem significantly without changing the best solution. This allows more complex and effective heuristics to be used. We show how to model the static offset alignment problem using linear programming, and we show that loop-dependent mobile offset alignment is sometimes necessary for optimum performance. We describe an algorithm with for determining mobile alignments for objects within do loops. We also identify situations in which replicated alignment is either required by the program itself or can be used to improve performance. We describe an algorithm based on network flow that replicates objects so as to minimize the total amount of broadcast communication in replication.

  15. On the orientation of the backbone dipoles in native folds

    PubMed Central

    Ripoll, Daniel R.; Vila, Jorge A.; Scheraga, Harold A.

    2005-01-01

    The role of electrostatic interactions in determining the native fold of proteins has been investigated by analyzing the alignment of peptide bond dipole moments with the local electrostatic field generated by the rest of the molecule with and without solvent effects. This alignment was calculated for a set of 112 native proteins by using charges from a gas phase potential. Most of the peptide dipoles in this set of proteins are on average aligned with the electrostatic field. The dipole moments associated with α-helical conformations show the best alignment with the electrostatic field, followed by residues in β-strand conformations. The dipole moments associated with other secondary structure elements are on average better aligned than in randomly generated conformations. The alignment of a dipole with the local electrostatic field depends on both the topology of the native fold and the charge distribution assumed for all of the residues. The influences of (i) solvent effects, (ii) different sets of charges, and (iii) the charge distribution assumed for the whole molecule were examined with a subset of 22 proteins each of which contains <30 ionizable groups. The results show that alternative charge distribution models lead to significant differences among the associated electrostatic fields, whereas the electrostatic field is less sensitive to the particular set of the adopted charges themselves (empirical conformational energy program for peptides or parameters for solvation energy). PMID:15894608

  16. G2S: a web-service for annotating genomic variants on 3D protein structures.

    PubMed

    Wang, Juexin; Sheridan, Robert; Sumer, S Onur; Schultz, Nikolaus; Xu, Dong; Gao, Jianjiong

    2018-06-01

    Accurately mapping and annotating genomic locations on 3D protein structures is a key step in structure-based analysis of genomic variants detected by recent large-scale sequencing efforts. There are several mapping resources currently available, but none of them provides a web API (Application Programming Interface) that supports programmatic access. We present G2S, a real-time web API that provides automated mapping of genomic variants on 3D protein structures. G2S can align genomic locations of variants, protein locations, or protein sequences to protein structures and retrieve the mapped residues from structures. G2S API uses REST-inspired design and it can be used by various clients such as web browsers, command terminals, programming languages and other bioinformatics tools for bringing 3D structures into genomic variant analysis. The webserver and source codes are freely available at https://g2s.genomenexus.org. g2s@genomenexus.org. Supplementary data are available at Bioinformatics online.

  17. Identifying and Aligning Expectations in a Mentoring Relationship

    PubMed Central

    Huskins, W. Charles; Silet, Karin; Weber‐Main, Anne Marie; Begg, Melissa D.; Fowler, Jr, Vance G.; Hamilton, John; Fleming, Michael

    2011-01-01

    Abstract The mentoring relationship between a scholar and their primary mentor is a core feature of research training. Anecdotal evidence suggests this relationship is adversely affected when scholar and mentor expectations are not aligned. We examined three questions: (1) What is the value in assuring that the expectations of scholars and mentors are mutually identified and aligned? (2) What types of programmatic interventions facilitate this process? (3) What types of expectations are important to identify and align? We addressed these questions through a systematic literature review, focus group interviews of mentors and scholars, a survey of Clinical and Translational Science Award (CTSA) KL2 program directors, and review of formal programmatic mechanisms used by KL2 programs. We found broad support for the importance of identifying and aligning the expectations of scholars and mentors and evidence that mentoring contracts, agreements, and training programs facilitate this process. These tools focus on aligning expectations with respect to the scholar’s research, education, professional development and career advancement as well as support, communication, and personal conduct and interpersonal relations. Research is needed to assess test the efficacy of formal alignment activities. Clin Trans Sci 2011; Volume 4: 439–447 PMID:22212226

  18. GCALIGNER 1.0: an alignment program to compute a multiple sample comparison data matrix from large eco-chemical datasets obtained by GC.

    PubMed

    Dellicour, Simon; Lecocq, Thomas

    2013-10-01

    GCALIGNER 1.0 is a computer program designed to perform a preliminary data comparison matrix of chemical data obtained by GC without MS information. The alignment algorithm is based on the comparison between the retention times of each detected compound in a sample. In this paper, we test the GCALIGNER efficiency on three datasets of the chemical secretions of bumble bees. The algorithm performs the alignment with a low error rate (<3%). GCALIGNER 1.0 is a useful, simple and free program based on an algorithm that enables the alignment of table-type data from GC. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Optimal simultaneous superpositioning of multiple structures with missing data.

    PubMed

    Theobald, Douglas L; Steindel, Phillip A

    2012-08-01

    Superpositioning is an essential technique in structural biology that facilitates the comparison and analysis of conformational differences among topologically similar structures. Performing a superposition requires a one-to-one correspondence, or alignment, of the point sets in the different structures. However, in practice, some points are usually 'missing' from several structures, for example, when the alignment contains gaps. Current superposition methods deal with missing data simply by superpositioning a subset of points that are shared among all the structures. This practice is inefficient, as it ignores important data, and it fails to satisfy the common least-squares criterion. In the extreme, disregarding missing positions prohibits the calculation of a superposition altogether. Here, we present a general solution for determining an optimal superposition when some of the data are missing. We use the expectation-maximization algorithm, a classic statistical technique for dealing with incomplete data, to find both maximum-likelihood solutions and the optimal least-squares solution as a special case. The methods presented here are implemented in THESEUS 2.0, a program for superpositioning macromolecular structures. ANSI C source code and selected compiled binaries for various computing platforms are freely available under the GNU open source license from http://www.theseus3d.org. dtheobald@brandeis.edu Supplementary data are available at Bioinformatics online.

  20. Information Technology (IT) Strategic Alignment: A Correlational Study between the Impact of IT Governance Structures and IT Strategic Alignment

    ERIC Educational Resources Information Center

    Asante, Keith K.

    2010-01-01

    This dissertation explored the extent to which Information Technology (IT) strategic alignment are impacted by IT governance structures. The study discusses several strategic alignment and IT governance literature that presents a gap in the literature domain. Subsequent studies researched issues surrounding why organizations are not able to align…

  1. Development of a verification program for deployable truss advanced technology

    NASA Technical Reports Server (NTRS)

    Dyer, Jack E.

    1988-01-01

    Use of large deployable space structures to satisfy the growth demands of space systems is contingent upon reducing the associated risks that pervade many related technical disciplines. The overall objectives of this program was to develop a detailed plan to verify deployable truss advanced technology applicable to future large space structures and to develop a preliminary design of a deployable truss reflector/beam structure for use a a technology demonstration test article. The planning is based on a Shuttle flight experiment program using deployable 5 and 15 meter aperture tetrahedral truss reflections and a 20 m long deployable truss beam structure. The plan addresses validation of analytical methods, the degree to which ground testing adequately simulates flight and in-space testing requirements for large precision antenna designs. Based on an assessment of future NASA and DOD space system requirements, the program was developed to verify four critical technology areas: deployment, shape accuracy and control, pointing and alignment, and articulation and maneuvers. The flight experiment technology verification objectives can be met using two shuttle flights with the total experiment integrated on a single Shuttle Test Experiment Platform (STEP) and a Mission Peculiar Experiment Support Structure (MPESS). First flight of the experiment can be achieved 60 months after go-ahead with a total program duration of 90 months.

  2. A Low Power and High Throughput Self Synchronous FPGA Using 65nm CMOS with Throughput Optimization by Pipeline Alignment

    NASA Astrophysics Data System (ADS)

    Stefan Devlin, Benjamin; Nakura, Toru; Ikeda, Makoto; Asada, Kunihiro

    We detail a self synchronous field programmable gate array (SSFPGA) with dual-pipeline (DP) architecture to conceal pre-charge time for dynamic logic, and its throughput optimization by using pipeline alignment implemented on benchmark circuits. A self synchronous LUT (SSLUT) consists of a three input tree-type structure with 8bits of SRAM for programming. A self synchronous switch box (SSSB) consists of both pass transistors and buffers to route signals, with 12bits of SRAM. One common block with one SSLUT and one SSSB occupies 2.2Mλ2 area with 35bits of SRAM, and the prototype SSFPGA with 34 × 30 (1020) blocks is designed and fabricated using 65nm CMOS. Measured results show at 1.2V 430MHz and 647MHz operation for a 3bit ripple carry adder, without and with throughput optimization, respectively. We find that using the proposed pipeline alignment techniques we can perform at maximum throughput of 647MHz in various benchmarks on the SSFPGA. We demonstrate up to 56.1 times throughput improvement with our pipeline alignment techniques. The pipeline alignment is carried out within the number of logic elements in the array and pipeline buffers in the switching matrix.

  3. Interdisciplinary Instruction in the Humanities Enrichment Program: Alignment of Programmatic, Pedagogic, and Learner Goals.

    ERIC Educational Resources Information Center

    Gudipati, Lakshmi

    This paper details the benefits of interdisciplinary studies, with particular focus on the Humanities Enrichment Program at the Community College of Philadelphia. The program uses a team-teaching, linked-course paradigm. Two courses from different disciplines are aligned, and faculty from each discipline teach the linked courses as humanities…

  4. Implementation of a novel portfolio of structured, curriculum-aligned, simulation-based, cardiothoracic surgery training courses: Evolving the delivery of surgical education.

    PubMed

    Moorjani, Narain; Lewis, Michael; Shah, Rajesh; Barnard, Sion; Graham, Tim; Rathinam, Sridhar

    2017-12-01

    The provision of high-quality cardiothoracic surgical training faces many challenges. This has generated an increased interest in simulation-based learning, which can provide a less stressful environment for deliberate practice. We developed a comprehensive, structured program of knowledge and simulation-based learning aligned to the official cardiothoracic surgery curriculum. A portfolio of 10 curriculum-aligned training courses was designed for cardiothoracic surgical trainees during their 6-year training program. The courses were delivered through a multitude of education methods, including live porcine operating simulation models, and were evaluated through a series of quantitative (5-point Likert-scale) and qualitative assessments. The trainees (n = 15-21 per course) also completed pre- and postsession self-confidence and competency levels for each training episode of knowledge and skill, respectively. In addition, board examination pass rates were assessed in the 3-year periods before and after implementation of the courses. Quantitative analysis of the trainees' feedback demonstrated an extremely positive view of the portfolio of the simulation-based training courses with excellent satisfaction scores (out of 5) for teaching sessions (4.44 ± 0.07), faculty (4.64 ± 0.07), content and materials (4.63 ± 0.07), and facilities (4.73 ± 0.05). The courses have shown a significant improvement in the post-self-confidence (7.98 ± 0.13 vs 5.62 ± 0.20, P < .01) and perceived self-competency (8.10 ± 0.10 vs 5.67 ± 0.11, P < .01) scores for all courses. Examination pass rates significantly improved in the 3-year period after attendance at the courses (94.82% ± 2.34% vs 76.26% ± 3.23%, P < .005). This study has described the implementation of the only extensive program of structured simulation-based courses that has been developed to complement clinical training in cardiothoracic surgery. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  5. Ab-initio conformational epitope structure prediction using genetic algorithm and SVM for vaccine design.

    PubMed

    Moghram, Basem Ameen; Nabil, Emad; Badr, Amr

    2018-01-01

    T-cell epitope structure identification is a significant challenging immunoinformatic problem within epitope-based vaccine design. Epitopes or antigenic peptides are a set of amino acids that bind with the Major Histocompatibility Complex (MHC) molecules. The aim of this process is presented by Antigen Presenting Cells to be inspected by T-cells. MHC-molecule-binding epitopes are responsible for triggering the immune response to antigens. The epitope's three-dimensional (3D) molecular structure (i.e., tertiary structure) reflects its proper function. Therefore, the identification of MHC class-II epitopes structure is a significant step towards epitope-based vaccine design and understanding of the immune system. In this paper, we propose a new technique using a Genetic Algorithm for Predicting the Epitope Structure (GAPES), to predict the structure of MHC class-II epitopes based on their sequence. The proposed Elitist-based genetic algorithm for predicting the epitope's tertiary structure is based on Ab-Initio Empirical Conformational Energy Program for Peptides (ECEPP) Force Field Model. The developed secondary structure prediction technique relies on Ramachandran Plot. We used two alignment algorithms: the ROSS alignment and TM-Score alignment. We applied four different alignment approaches to calculate the similarity scores of the dataset under test. We utilized the support vector machine (SVM) classifier as an evaluation of the prediction performance. The prediction accuracy and the Area Under Receiver Operating Characteristic (ROC) Curve (AUC) were calculated as measures of performance. The calculations are performed on twelve similarity-reduced datasets of the Immune Epitope Data Base (IEDB) and a large dataset of peptide-binding affinities to HLA-DRB1*0101. The results showed that GAPES was reliable and very accurate. We achieved an average prediction accuracy of 93.50% and an average AUC of 0.974 in the IEDB dataset. Also, we achieved an accuracy of 95.125% and an AUC of 0.987 on the HLA-DRB1*0101 allele of the Wang benchmark dataset. The results indicate that the proposed prediction technique "GAPES" is a promising technique that will help researchers and scientists to predict the protein structure and it will assist them in the intelligent design of new epitope-based vaccines. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. The twilight zone of cis element alignments.

    PubMed

    Sebastian, Alvaro; Contreras-Moreira, Bruno

    2013-02-01

    Sequence alignment of proteins and nucleic acids is a routine task in bioinformatics. Although the comparison of complete peptides, genes or genomes can be undertaken with a great variety of tools, the alignment of short DNA sequences and motifs entails pitfalls that have not been fully addressed yet. Here we confront the structural superposition of transcription factors with the sequence alignment of their recognized cis elements. Our goals are (i) to test TFcompare (http://floresta.eead.csic.es/tfcompare), a structural alignment method for protein-DNA complexes; (ii) to benchmark the pairwise alignment of regulatory elements; (iii) to define the confidence limits and the twilight zone of such alignments and (iv) to evaluate the relevance of these thresholds with elements obtained experimentally. We find that the structure of cis elements and protein-DNA interfaces is significantly more conserved than their sequence and measures how this correlates with alignment errors when only sequence information is considered. Our results confirm that DNA motifs in the form of matrices produce better alignments than individual sequences. Finally, we report that empirical and theoretically derived twilight thresholds are useful for estimating the natural plasticity of regulatory sequences, and hence for filtering out unreliable alignments.

  7. The twilight zone of cis element alignments

    PubMed Central

    Sebastian, Alvaro; Contreras-Moreira, Bruno

    2013-01-01

    Sequence alignment of proteins and nucleic acids is a routine task in bioinformatics. Although the comparison of complete peptides, genes or genomes can be undertaken with a great variety of tools, the alignment of short DNA sequences and motifs entails pitfalls that have not been fully addressed yet. Here we confront the structural superposition of transcription factors with the sequence alignment of their recognized cis elements. Our goals are (i) to test TFcompare (http://floresta.eead.csic.es/tfcompare), a structural alignment method for protein–DNA complexes; (ii) to benchmark the pairwise alignment of regulatory elements; (iii) to define the confidence limits and the twilight zone of such alignments and (iv) to evaluate the relevance of these thresholds with elements obtained experimentally. We find that the structure of cis elements and protein–DNA interfaces is significantly more conserved than their sequence and measures how this correlates with alignment errors when only sequence information is considered. Our results confirm that DNA motifs in the form of matrices produce better alignments than individual sequences. Finally, we report that empirical and theoretically derived twilight thresholds are useful for estimating the natural plasticity of regulatory sequences, and hence for filtering out unreliable alignments. PMID:23268451

  8. Improved measurements of RNA structure conservation with generalized centroid estimators.

    PubMed

    Okada, Yohei; Saito, Yutaka; Sato, Kengo; Sakakibara, Yasubumi

    2011-01-01

    Identification of non-protein-coding RNAs (ncRNAs) in genomes is a crucial task for not only molecular cell biology but also bioinformatics. Secondary structures of ncRNAs are employed as a key feature of ncRNA analysis since biological functions of ncRNAs are deeply related to their secondary structures. Although the minimum free energy (MFE) structure of an RNA sequence is regarded as the most stable structure, MFE alone could not be an appropriate measure for identifying ncRNAs since the free energy is heavily biased by the nucleotide composition. Therefore, instead of MFE itself, several alternative measures for identifying ncRNAs have been proposed such as the structure conservation index (SCI) and the base pair distance (BPD), both of which employ MFE structures. However, these measurements are unfortunately not suitable for identifying ncRNAs in some cases including the genome-wide search and incur high false discovery rate. In this study, we propose improved measurements based on SCI and BPD, applying generalized centroid estimators to incorporate the robustness against low quality multiple alignments. Our experiments show that our proposed methods achieve higher accuracy than the original SCI and BPD for not only human-curated structural alignments but also low quality alignments produced by CLUSTAL W. Furthermore, the centroid-based SCI on CLUSTAL W alignments is more accurate than or comparable with that of the original SCI on structural alignments generated with RAF, a high quality structural aligner, for which twofold expensive computational time is required on average. We conclude that our methods are more suitable for genome-wide alignments which are of low quality from the point of view on secondary structures than the original SCI and BPD.

  9. ChromAlign: A two-step algorithmic procedure for time alignment of three-dimensional LC-MS chromatographic surfaces.

    PubMed

    Sadygov, Rovshan G; Maroto, Fernando Martin; Hühmer, Andreas F R

    2006-12-15

    We present an algorithmic approach to align three-dimensional chromatographic surfaces of LC-MS data of complex mixture samples. The approach consists of two steps. In the first step, we prealign chromatographic profiles: two-dimensional projections of chromatographic surfaces. This is accomplished by correlation analysis using fast Fourier transforms. In this step, a temporal offset that maximizes the overlap and dot product between two chromatographic profiles is determined. In the second step, the algorithm generates correlation matrix elements between full mass scans of the reference and sample chromatographic surfaces. The temporal offset from the first step indicates a range of the mass scans that are possibly correlated, then the correlation matrix is calculated only for these mass scans. The correlation matrix carries information on highly correlated scans, but it does not itself determine the scan or time alignment. Alignment is determined as a path in the correlation matrix that maximizes the sum of the correlation matrix elements. The computational complexity of the optimal path generation problem is reduced by the use of dynamic programming. The program produces time-aligned surfaces. The use of the temporal offset from the first step in the second step reduces the computation time for generating the correlation matrix and speeds up the process. The algorithm has been implemented in a program, ChromAlign, developed in C++ language for the .NET2 environment in WINDOWS XP. In this work, we demonstrate the applications of ChromAlign to alignment of LC-MS surfaces of several datasets: a mixture of known proteins, samples from digests of surface proteins of T-cells, and samples prepared from digests of cerebrospinal fluid. ChromAlign accurately aligns the LC-MS surfaces we studied. In these examples, we discuss various aspects of the alignment by ChromAlign, such as constant time axis shifts and warping of chromatographic surfaces.

  10. Mobile and replicated alignment of arrays in data-parallel programs

    NASA Technical Reports Server (NTRS)

    Chatterjee, Siddhartha; Gilbert, John R.; Schreiber, Robert

    1993-01-01

    When a data-parallel language like FORTRAN 90 is compiled for a distributed-memory machine, aggregate data objects (such as arrays) are distributed across the processor memories. The mapping determines the amount of residual communication needed to bring operands of parallel operations into alignment with each other. A common approach is to break the mapping into two stages: first, an alignment that maps all the objects to an abstract template, and then a distribution that maps the template to the processors. We solve two facets of the problem of finding alignments that reduce residual communication: we determine alignments that vary in loops, and objects that should have replicated alignments. We show that loop-dependent mobile alignment is sometimes necessary for optimum performance, and we provide algorithms with which a compiler can determine good mobile alignments for objects within do loops. We also identify situations in which replicated alignment is either required by the program itself (via spread operations) or can be used to improve performance. We propose an algorithm based on network flow that determines which objects to replicate so as to minimize the total amount of broadcast communication in replication. This work on mobile and replicated alignment extends our earlier work on determining static alignment.

  11. Redesigning and Aligning Assessment and Evaluation for a Federally Funded Math and Science Teacher Educational Program

    ERIC Educational Resources Information Center

    Hardre, Patricia L.; Slater, Janis; Nanny, Mark

    2010-01-01

    This paper examines the redesign of evaluation components for a teacher professional development project funded by the National Science Foundation. It focuses on aligning evaluation instrumentation and strategies with program goals, research goals and program evaluation best practices. The study identifies weaknesses in the original (year 1)…

  12. Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction.

    PubMed

    Saed, Mohand O; Torbati, Amir H; Nair, Devatha P; Yakacki, Christopher M

    2016-01-19

    This study presents a novel two-stage thiol-acrylate Michael addition-photopolymerization (TAMAP) reaction to prepare main-chain liquid-crystalline elastomers (LCEs) with facile control over network structure and programming of an aligned monodomain. Tailored LCE networks were synthesized using routine mixing of commercially available starting materials and pouring monomer solutions into molds to cure. An initial polydomain LCE network is formed via a self-limiting thiol-acrylate Michael-addition reaction. Strain-to-failure and glass transition behavior were investigated as a function of crosslinking monomer, pentaerythritol tetrakis(3-mercaptopropionate) (PETMP). An example non-stoichiometric system of 15 mol% PETMP thiol groups and an excess of 15 mol% acrylate groups was used to demonstrate the robust nature of the material. The LCE formed an aligned and transparent monodomain when stretched, with a maximum failure strain over 600%. Stretched LCE samples were able to demonstrate both stress-driven thermal actuation when held under a constant bias stress or the shape-memory effect when stretched and unloaded. A permanently programmed monodomain was achieved via a second-stage photopolymerization reaction of the excess acrylate groups when the sample was in the stretched state. LCE samples were photo-cured and programmed at 100%, 200%, 300%, and 400% strain, with all samples demonstrating over 90% shape fixity when unloaded. The magnitude of total stress-free actuation increased from 35% to 115% with increased programming strain. Overall, the two-stage TAMAP methodology is presented as a powerful tool to prepare main-chain LCE systems and explore structure-property-performance relationships in these fascinating stimuli-sensitive materials.

  13. Describing sequencing results of structural chromosome rearrangements with a suggested next-generation cytogenetic nomenclature.

    PubMed

    Ordulu, Zehra; Wong, Kristen E; Currall, Benjamin B; Ivanov, Andrew R; Pereira, Shahrin; Althari, Sara; Gusella, James F; Talkowski, Michael E; Morton, Cynthia C

    2014-05-01

    With recent rapid advances in genomic technologies, precise delineation of structural chromosome rearrangements at the nucleotide level is becoming increasingly feasible. In this era of "next-generation cytogenetics" (i.e., an integration of traditional cytogenetic techniques and next-generation sequencing), a consensus nomenclature is essential for accurate communication and data sharing. Currently, nomenclature for describing the sequencing data of these aberrations is lacking. Herein, we present a system called Next-Gen Cytogenetic Nomenclature, which is concordant with the International System for Human Cytogenetic Nomenclature (2013). This system starts with the alignment of rearrangement sequences by BLAT or BLAST (alignment tools) and arrives at a concise and detailed description of chromosomal changes. To facilitate usage and implementation of this nomenclature, we are developing a program designated BLA(S)T Output Sequence Tool of Nomenclature (BOSToN), a demonstrative version of which is accessible online. A standardized characterization of structural chromosomal rearrangements is essential both for research analyses and for application in the clinical setting. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  14. Pre-calculated protein structure alignments at the RCSB PDB website.

    PubMed

    Prlic, Andreas; Bliven, Spencer; Rose, Peter W; Bluhm, Wolfgang F; Bizon, Chris; Godzik, Adam; Bourne, Philip E

    2010-12-01

    With the continuous growth of the RCSB Protein Data Bank (PDB), providing an up-to-date systematic structure comparison of all protein structures poses an ever growing challenge. Here, we present a comparison tool for calculating both 1D protein sequence and 3D protein structure alignments. This tool supports various applications at the RCSB PDB website. First, a structure alignment web service calculates pairwise alignments. Second, a stand-alone application runs alignments locally and visualizes the results. Third, pre-calculated 3D structure comparisons for the whole PDB are provided and updated on a weekly basis. These three applications allow users to discover novel relationships between proteins available either at the RCSB PDB or provided by the user. A web user interface is available at http://www.rcsb.org/pdb/workbench/workbench.do. The source code is available under the LGPL license from http://www.biojava.org. A source bundle, prepared for local execution, is available from http://source.rcsb.org andreas@sdsc.edu; pbourne@ucsd.edu.

  15. Four RNA families with functional transient structures

    PubMed Central

    Zhu, Jing Yun A; Meyer, Irmtraud M

    2015-01-01

    Protein-coding and non-coding RNA transcripts perform a wide variety of cellular functions in diverse organisms. Several of their functional roles are expressed and modulated via RNA structure. A given transcript, however, can have more than a single functional RNA structure throughout its life, a fact which has been previously overlooked. Transient RNA structures, for example, are only present during specific time intervals and cellular conditions. We here introduce four RNA families with transient RNA structures that play distinct and diverse functional roles. Moreover, we show that these transient RNA structures are structurally well-defined and evolutionarily conserved. Since Rfam annotates one structure for each family, there is either no annotation for these transient structures or no such family. Thus, our alignments either significantly update and extend the existing Rfam families or introduce a new RNA family to Rfam. For each of the four RNA families, we compile a multiple-sequence alignment based on experimentally verified transient and dominant (dominant in terms of either the thermodynamic stability and/or attention received so far) RNA secondary structures using a combination of automated search via covariance model and manual curation. The first alignment is the Trp operon leader which regulates the operon transcription in response to tryptophan abundance through alternative structures. The second alignment is the HDV ribozyme which we extend to the 5′ flanking sequence. This flanking sequence is involved in the regulation of the transcript's self-cleavage activity. The third alignment is the 5′ UTR of the maturation protein from Levivirus which contains a transient structure that temporarily postpones the formation of the final inhibitory structure to allow translation of maturation protein. The fourth and last alignment is the SAM riboswitch which regulates the downstream gene expression by assuming alternative structures upon binding of SAM. All transient and dominant structures are mapped to our new alignments introduced here. PMID:25751035

  16. Four RNA families with functional transient structures.

    PubMed

    Zhu, Jing Yun A; Meyer, Irmtraud M

    2015-01-01

    Protein-coding and non-coding RNA transcripts perform a wide variety of cellular functions in diverse organisms. Several of their functional roles are expressed and modulated via RNA structure. A given transcript, however, can have more than a single functional RNA structure throughout its life, a fact which has been previously overlooked. Transient RNA structures, for example, are only present during specific time intervals and cellular conditions. We here introduce four RNA families with transient RNA structures that play distinct and diverse functional roles. Moreover, we show that these transient RNA structures are structurally well-defined and evolutionarily conserved. Since Rfam annotates one structure for each family, there is either no annotation for these transient structures or no such family. Thus, our alignments either significantly update and extend the existing Rfam families or introduce a new RNA family to Rfam. For each of the four RNA families, we compile a multiple-sequence alignment based on experimentally verified transient and dominant (dominant in terms of either the thermodynamic stability and/or attention received so far) RNA secondary structures using a combination of automated search via covariance model and manual curation. The first alignment is the Trp operon leader which regulates the operon transcription in response to tryptophan abundance through alternative structures. The second alignment is the HDV ribozyme which we extend to the 5' flanking sequence. This flanking sequence is involved in the regulation of the transcript's self-cleavage activity. The third alignment is the 5' UTR of the maturation protein from Levivirus which contains a transient structure that temporarily postpones the formation of the final inhibitory structure to allow translation of maturation protein. The fourth and last alignment is the SAM riboswitch which regulates the downstream gene expression by assuming alternative structures upon binding of SAM. All transient and dominant structures are mapped to our new alignments introduced here.

  17. L-GRAAL: Lagrangian graphlet-based network aligner.

    PubMed

    Malod-Dognin, Noël; Pržulj, Nataša

    2015-07-01

    Discovering and understanding patterns in networks of protein-protein interactions (PPIs) is a central problem in systems biology. Alignments between these networks aid functional understanding as they uncover important information, such as evolutionary conserved pathways, protein complexes and functional orthologs. A few methods have been proposed for global PPI network alignments, but because of NP-completeness of underlying sub-graph isomorphism problem, producing topologically and biologically accurate alignments remains a challenge. We introduce a novel global network alignment tool, Lagrangian GRAphlet-based ALigner (L-GRAAL), which directly optimizes both the protein and the interaction functional conservations, using a novel alignment search heuristic based on integer programming and Lagrangian relaxation. We compare L-GRAAL with the state-of-the-art network aligners on the largest available PPI networks from BioGRID and observe that L-GRAAL uncovers the largest common sub-graphs between the networks, as measured by edge-correctness and symmetric sub-structures scores, which allow transferring more functional information across networks. We assess the biological quality of the protein mappings using the semantic similarity of their Gene Ontology annotations and observe that L-GRAAL best uncovers functionally conserved proteins. Furthermore, we introduce for the first time a measure of the semantic similarity of the mapped interactions and show that L-GRAAL also uncovers best functionally conserved interactions. In addition, we illustrate on the PPI networks of baker's yeast and human the ability of L-GRAAL to predict new PPIs. Finally, L-GRAAL's results are the first to show that topological information is more important than sequence information for uncovering functionally conserved interactions. L-GRAAL is coded in C++. Software is available at: http://bio-nets.doc.ic.ac.uk/L-GRAAL/. n.malod-dognin@imperial.ac.uk Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

  18. Alignment Pins for Assembling and Disassembling Structures

    NASA Technical Reports Server (NTRS)

    Campbell, Oliver C.

    2008-01-01

    Simple, easy-to-use, highly effective tooling has been devised for maintaining alignment of bolt holes in mating structures during assembly and disassembly of the structures. The tooling was originally used during removal of a body flap from the space shuttle Atlantis, in which misalignments during removal of the last few bolts could cause the bolts to bind in their holes. By suitably modifying the dimensions of the tooling components, the basic design of the tooling can readily be adapted to other structures that must be maintained in alignment. The tooling includes tapered, internally threaded alignment pins designed to fit in the bolt holes in one of the mating structures, plus a draw bolt and a cup that are used to install or remove each alignment pin. In preparation for disassembly of two mating structures, external supports are provided to prevent unintended movement of the structures. During disassembly of the structures, as each bolt that joins the structures is removed, an alignment pin is installed in its place. Once all the bolts have been removed and replaced with pins, the pins maintain alignment as the structures are gently pushed or pulled apart on the supports. In assembling the two structures, one reverses the procedure described above: pins are installed in the bolt holes, the structures are pulled or pushed together on the supports, then the pins are removed and replaced with bolts. The figure depicts the tooling and its use. To install an alignment pin in a bolt hole in a structural panel, the tapered end of the pin is inserted from one side of the panel, the cup is placed over the pin on the opposite side of the panel, the draw bolt is inserted through the cup and threaded into the pin, the draw bolt is tightened to pull the pin until the pin is seated firmly in the hole, then the draw bolt and cup are removed, leaving the pin in place. To remove an alignment pin, the cup is placed over the pin on the first-mentioned side of the panel, the draw bolt is inserted through the cup and threaded into the pin, then the draw bolt is tightened to pull the pin out of the hole.

  19. Ligand Binding Site Detection by Local Structure Alignment and Its Performance Complementarity

    PubMed Central

    Lee, Hui Sun; Im, Wonpil

    2013-01-01

    Accurate determination of potential ligand binding sites (BS) is a key step for protein function characterization and structure-based drug design. Despite promising results of template-based BS prediction methods using global structure alignment (GSA), there is a room to improve the performance by properly incorporating local structure alignment (LSA) because BS are local structures and often similar for proteins with dissimilar global folds. We present a template-based ligand BS prediction method using G-LoSA, our LSA tool. A large benchmark set validation shows that G-LoSA predicts drug-like ligands’ positions in single-chain protein targets more precisely than TM-align, a GSA-based method, while the overall success rate of TM-align is better. G-LoSA is particularly efficient for accurate detection of local structures conserved across proteins with diverse global topologies. Recognizing the performance complementarity of G-LoSA to TM-align and a non-template geometry-based method, fpocket, a robust consensus scoring method, CMCS-BSP (Complementary Methods and Consensus Scoring for ligand Binding Site Prediction), is developed and shows improvement on prediction accuracy. The G-LoSA source code is freely available at http://im.bioinformatics.ku.edu/GLoSA. PMID:23957286

  20. MaxAlign: maximizing usable data in an alignment.

    PubMed

    Gouveia-Oliveira, Rodrigo; Sackett, Peter W; Pedersen, Anders G

    2007-08-28

    The presence of gaps in an alignment of nucleotide or protein sequences is often an inconvenience for bioinformatical studies. In phylogenetic and other analyses, for instance, gapped columns are often discarded entirely from the alignment. MaxAlign is a program that optimizes the alignment prior to such analyses. Specifically, it maximizes the number of nucleotide (or amino acid) symbols that are present in gap-free columns - the alignment area - by selecting the optimal subset of sequences to exclude from the alignment. MaxAlign can be used prior to phylogenetic and bioinformatical analyses as well as in other situations where this form of alignment improvement is useful. In this work we test MaxAlign's performance in these tasks and compare the accuracy of phylogenetic estimates including and excluding gapped columns from the analysis, with and without processing with MaxAlign. In this paper we also introduce a new simple measure of tree similarity, Normalized Symmetric Similarity (NSS) that we consider useful for comparing tree topologies. We demonstrate how MaxAlign is helpful in detecting misaligned or defective sequences without requiring manual inspection. We also show that it is not advisable to exclude gapped columns from phylogenetic analyses unless MaxAlign is used first. Finally, we find that the sequences removed by MaxAlign from an alignment tend to be those that would otherwise be associated with low phylogenetic accuracy, and that the presence of gaps in any given sequence does not seem to disturb the phylogenetic estimates of other sequences. The MaxAlign web-server is freely available online at http://www.cbs.dtu.dk/services/MaxAlign where supplementary information can also be found. The program is also freely available as a Perl stand-alone package.

  1. Alignment methods: strategies, challenges, benchmarking, and comparative overview.

    PubMed

    Löytynoja, Ari

    2012-01-01

    Comparative evolutionary analyses of molecular sequences are solely based on the identities and differences detected between homologous characters. Errors in this homology statement, that is errors in the alignment of the sequences, are likely to lead to errors in the downstream analyses. Sequence alignment and phylogenetic inference are tightly connected and many popular alignment programs use the phylogeny to divide the alignment problem into smaller tasks. They then neglect the phylogenetic tree, however, and produce alignments that are not evolutionarily meaningful. The use of phylogeny-aware methods reduces the error but the resulting alignments, with evolutionarily correct representation of homology, can challenge the existing practices and methods for viewing and visualising the sequences. The inter-dependency of alignment and phylogeny can be resolved by joint estimation of the two; methods based on statistical models allow for inferring the alignment parameters from the data and correctly take into account the uncertainty of the solution but remain computationally challenging. Widely used alignment methods are based on heuristic algorithms and unlikely to find globally optimal solutions. The whole concept of one correct alignment for the sequences is questionable, however, as there typically exist vast numbers of alternative, roughly equally good alignments that should also be considered. This uncertainty is hidden by many popular alignment programs and is rarely correctly taken into account in the downstream analyses. The quest for finding and improving the alignment solution is complicated by the lack of suitable measures of alignment goodness. The difficulty of comparing alternative solutions also affects benchmarks of alignment methods and the results strongly depend on the measure used. As the effects of alignment error cannot be predicted, comparing the alignments' performance in downstream analyses is recommended.

  2. MultiSeq: unifying sequence and structure data for evolutionary analysis

    PubMed Central

    Roberts, Elijah; Eargle, John; Wright, Dan; Luthey-Schulten, Zaida

    2006-01-01

    Background Since the publication of the first draft of the human genome in 2000, bioinformatic data have been accumulating at an overwhelming pace. Currently, more than 3 million sequences and 35 thousand structures of proteins and nucleic acids are available in public databases. Finding correlations in and between these data to answer critical research questions is extremely challenging. This problem needs to be approached from several directions: information science to organize and search the data; information visualization to assist in recognizing correlations; mathematics to formulate statistical inferences; and biology to analyze chemical and physical properties in terms of sequence and structure changes. Results Here we present MultiSeq, a unified bioinformatics analysis environment that allows one to organize, display, align and analyze both sequence and structure data for proteins and nucleic acids. While special emphasis is placed on analyzing the data within the framework of evolutionary biology, the environment is also flexible enough to accommodate other usage patterns. The evolutionary approach is supported by the use of predefined metadata, adherence to standard ontological mappings, and the ability for the user to adjust these classifications using an electronic notebook. MultiSeq contains a new algorithm to generate complete evolutionary profiles that represent the topology of the molecular phylogenetic tree of a homologous group of distantly related proteins. The method, based on the multidimensional QR factorization of multiple sequence and structure alignments, removes redundancy from the alignments and orders the protein sequences by increasing linear dependence, resulting in the identification of a minimal basis set of sequences that spans the evolutionary space of the homologous group of proteins. Conclusion MultiSeq is a major extension of the Multiple Alignment tool that is provided as part of VMD, a structural visualization program for analyzing molecular dynamics simulations. Both are freely distributed by the NIH Resource for Macromolecular Modeling and Bioinformatics and MultiSeq is included with VMD starting with version 1.8.5. The MultiSeq website has details on how to download and use the software: PMID:16914055

  3. A Web interface generator for molecular biology programs in Unix.

    PubMed

    Letondal, C

    2001-01-01

    Almost all users encounter problems using sequence analysis programs. Not only are they difficult to learn because of the parameters, syntax and semantic, but many are different. That is why we have developed a Web interface generator for more than 150 molecular biology command-line driven programs, including: phylogeny, gene prediction, alignment, RNA, DNA and protein analysis, motif discovery, structure analysis and database searching programs. The generator uses XML as a high-level description language of the legacy software parameters. Its aim is to provide users with the equivalent of a basic Unix environment, with program combination, customization and basic scripting through macro registration. The program has been used for three years by about 15000 users throughout the world; it has recently been installed on other sites and evaluated as a standard user interface for EMBOSS programs.

  4. Astronomical Alignments in a Neolithic Chinese Site?

    NASA Astrophysics Data System (ADS)

    Nelson, S.; Stencel, R. E.

    1997-12-01

    In the Manchurian province of Liaoning, near 41N19' and 119E30', exist ruins of a middle Neolithic society (2500 to 4000 BC) known as the Hongshan culture. This location, called Niuheliang, is comprised of 16 locations with monumental structures scattered over 80 square kilometers of hills. Most are stone burial structures that contain jade artifacts implying wealth and power. One structure is unique in being unusually shaped and containing oversized effigies of goddess figures. This structure also has a commanding view of the surrounding landscape. The presence of decorated pottery, jade and worked copper suggests the Hongshan people were sophisticated artisans and engaged in long-distance trading. During 1997, we've conducted a course at Denver as part of our Core Curriculum program for upper division students, that has examined the astronomical and cultural aspects of the Niuheliang site, to attempt to determine whether these contemporaries of the builders of Stonehenge may have included astronomical alignments into their constructions. The preliminary result of our studies suggests that certain monuments have potential for lunar standstill observation from the "goddess temple". For updates on these results, please see our website: www.du.edu/ rstencel/core2103.html.

  5. Structure-Based Sequence Alignment of the Transmembrane Domains of All Human GPCRs: Phylogenetic, Structural and Functional Implications

    PubMed Central

    Cvicek, Vaclav; Goddard, William A.; Abrol, Ravinder

    2016-01-01

    The understanding of G-protein coupled receptors (GPCRs) is undergoing a revolution due to increased information about their signaling and the experimental determination of structures for more than 25 receptors. The availability of at least one receptor structure for each of the GPCR classes, well separated in sequence space, enables an integrated superfamily-wide analysis to identify signatures involving the role of conserved residues, conserved contacts, and downstream signaling in the context of receptor structures. In this study, we align the transmembrane (TM) domains of all experimental GPCR structures to maximize the conserved inter-helical contacts. The resulting superfamily-wide GpcR Sequence-Structure (GRoSS) alignment of the TM domains for all human GPCR sequences is sufficient to generate a phylogenetic tree that correctly distinguishes all different GPCR classes, suggesting that the class-level differences in the GPCR superfamily are encoded at least partly in the TM domains. The inter-helical contacts conserved across all GPCR classes describe the evolutionarily conserved GPCR structural fold. The corresponding structural alignment of the inactive and active conformations, available for a few GPCRs, identifies activation hot-spot residues in the TM domains that get rewired upon activation. Many GPCR mutations, known to alter receptor signaling and cause disease, are located at these conserved contact and activation hot-spot residue positions. The GRoSS alignment places the chemosensory receptor subfamilies for bitter taste (TAS2R) and pheromones (Vomeronasal, VN1R) in the rhodopsin family, known to contain the chemosensory olfactory receptor subfamily. The GRoSS alignment also enables the quantification of the structural variability in the TM regions of experimental structures, useful for homology modeling and structure prediction of receptors. Furthermore, this alignment identifies structurally and functionally important residues in all human GPCRs. These residues can be used to make testable hypotheses about the structural basis of receptor function and about the molecular basis of disease-associated single nucleotide polymorphisms. PMID:27028541

  6. Efficient computation of the phylogenetic likelihood function on multi-gene alignments and multi-core architectures.

    PubMed

    Stamatakis, Alexandros; Ott, Michael

    2008-12-27

    The continuous accumulation of sequence data, for example, due to novel wet-laboratory techniques such as pyrosequencing, coupled with the increasing popularity of multi-gene phylogenies and emerging multi-core processor architectures that face problems of cache congestion, poses new challenges with respect to the efficient computation of the phylogenetic maximum-likelihood (ML) function. Here, we propose two approaches that can significantly speed up likelihood computations that typically represent over 95 per cent of the computational effort conducted by current ML or Bayesian inference programs. Initially, we present a method and an appropriate data structure to efficiently compute the likelihood score on 'gappy' multi-gene alignments. By 'gappy' we denote sampling-induced gaps owing to missing sequences in individual genes (partitions), i.e. not real alignment gaps. A first proof-of-concept implementation in RAXML indicates that this approach can accelerate inferences on large and gappy alignments by approximately one order of magnitude. Moreover, we present insights and initial performance results on multi-core architectures obtained during the transition from an OpenMP-based to a Pthreads-based fine-grained parallelization of the ML function.

  7. Optimal Alignment of Structures for Finite and Periodic Systems.

    PubMed

    Griffiths, Matthew; Niblett, Samuel P; Wales, David J

    2017-10-10

    Finding the optimal alignment between two structures is important for identifying the minimum root-mean-square distance (RMSD) between them and as a starting point for calculating pathways. Most current algorithms for aligning structures are stochastic, scale exponentially with the size of structure, and the performance can be unreliable. We present two complementary methods for aligning structures corresponding to isolated clusters of atoms and to condensed matter described by a periodic cubic supercell. The first method (Go-PERMDIST), a branch and bound algorithm, locates the global minimum RMSD deterministically in polynomial time. The run time increases for larger RMSDs. The second method (FASTOVERLAP) is a heuristic algorithm that aligns structures by finding the global maximum kernel correlation between them using fast Fourier transforms (FFTs) and fast SO(3) transforms (SOFTs). For periodic systems, FASTOVERLAP scales with the square of the number of identical atoms in the system, reliably finds the best alignment between structures that are not too distant, and shows significantly better performance than existing algorithms. The expected run time for Go-PERMDIST is longer than FASTOVERLAP for periodic systems. For finite clusters, the FASTOVERLAP algorithm is competitive with existing algorithms. The expected run time for Go-PERMDIST to find the global RMSD between two structures deterministically is generally longer than for existing stochastic algorithms. However, with an earlier exit condition, Go-PERMDIST exhibits similar or better performance.

  8. High-throughput sequence alignment using Graphics Processing Units

    PubMed Central

    Schatz, Michael C; Trapnell, Cole; Delcher, Arthur L; Varshney, Amitabh

    2007-01-01

    Background The recent availability of new, less expensive high-throughput DNA sequencing technologies has yielded a dramatic increase in the volume of sequence data that must be analyzed. These data are being generated for several purposes, including genotyping, genome resequencing, metagenomics, and de novo genome assembly projects. Sequence alignment programs such as MUMmer have proven essential for analysis of these data, but researchers will need ever faster, high-throughput alignment tools running on inexpensive hardware to keep up with new sequence technologies. Results This paper describes MUMmerGPU, an open-source high-throughput parallel pairwise local sequence alignment program that runs on commodity Graphics Processing Units (GPUs) in common workstations. MUMmerGPU uses the new Compute Unified Device Architecture (CUDA) from nVidia to align multiple query sequences against a single reference sequence stored as a suffix tree. By processing the queries in parallel on the highly parallel graphics card, MUMmerGPU achieves more than a 10-fold speedup over a serial CPU version of the sequence alignment kernel, and outperforms the exact alignment component of MUMmer on a high end CPU by 3.5-fold in total application time when aligning reads from recent sequencing projects using Solexa/Illumina, 454, and Sanger sequencing technologies. Conclusion MUMmerGPU is a low cost, ultra-fast sequence alignment program designed to handle the increasing volume of data produced by new, high-throughput sequencing technologies. MUMmerGPU demonstrates that even memory-intensive applications can run significantly faster on the relatively low-cost GPU than on the CPU. PMID:18070356

  9. Aligning Assessments for COSMA Accreditation

    ERIC Educational Resources Information Center

    Laird, Curt; Johnson, Dennis A.; Alderman, Heather

    2015-01-01

    Many higher education sport management programs are currently in the process of seeking accreditation from the Commission on Sport Management Accreditation (COSMA). This article provides a best-practice method for aligning student learning outcomes with a sport management program's mission and goals. Formative and summative assessment procedures…

  10. Automatic target alignment of the Helios laser system

    NASA Astrophysics Data System (ADS)

    Liberman, I.; Viswanathan, V. K.; Klein, M.; Seery, B. D.

    1980-05-01

    An automatic target-alignment technique for the Helios laser facility is reported and verified experimentally. The desired alignment condition is completely described by an autocollimation test. A computer program examines the autocollimated return pattern from the surrogate target and correctly describes any changes required in mirror orientation to yield optimum target alignment with either aberrated or misaligned beams. Automated on-line target alignment is thus shown to be feasible.

  11. Four-dimensional Printing of Liquid Crystal Elastomers.

    PubMed

    Ambulo, Cedric P; Burroughs, Julia J; Boothby, Jennifer M; Kim, Hyun; Shankar, M Ravi; Ware, Taylor H

    2017-10-25

    Three-dimensional structures capable of reversible changes in shape, i.e., four-dimensional-printed structures, may enable new generations of soft robotics, implantable medical devices, and consumer products. Here, thermally responsive liquid crystal elastomers (LCEs) are direct-write printed into 3D structures with a controlled molecular order. Molecular order is locally programmed by controlling the print path used to build the 3D object, and this order controls the stimulus response. Each aligned LCE filament undergoes 40% reversible contraction along the print direction on heating. By printing objects with controlled geometry and stimulus response, magnified shape transformations, for example, volumetric contractions or rapid, repetitive snap-through transitions, are realized.

  12. Receptor-based 3D QSAR analysis of estrogen receptor ligands - merging the accuracy of receptor-based alignments with the computational efficiency of ligand-based methods

    NASA Astrophysics Data System (ADS)

    Sippl, Wolfgang

    2000-08-01

    One of the major challenges in computational approaches to drug design is the accurate prediction of binding affinity of biomolecules. In the present study several prediction methods for a published set of estrogen receptor ligands are investigated and compared. The binding modes of 30 ligands were determined using the docking program AutoDock and were compared with available X-ray structures of estrogen receptor-ligand complexes. On the basis of the docking results an interaction energy-based model, which uses the information of the whole ligand-receptor complex, was generated. Several parameters were modified in order to analyze their influence onto the correlation between binding affinities and calculated ligand-receptor interaction energies. The highest correlation coefficient ( r 2 = 0.617, q 2 LOO = 0.570) was obtained considering protein flexibility during the interaction energy evaluation. The second prediction method uses a combination of receptor-based and 3D quantitative structure-activity relationships (3D QSAR) methods. The ligand alignment obtained from the docking simulations was taken as basis for a comparative field analysis applying the GRID/GOLPE program. Using the interaction field derived with a water probe and applying the smart region definition (SRD) variable selection, a significant and robust model was obtained ( r 2 = 0.991, q 2 LOO = 0.921). The predictive ability of the established model was further evaluated by using a test set of six additional compounds. The comparison with the generated interaction energy-based model and with a traditional CoMFA model obtained using a ligand-based alignment ( r 2 = 0.951, q 2 LOO = 0.796) indicates that the combination of receptor-based and 3D QSAR methods is able to improve the quality of the underlying model.

  13. Comparison of expectations and beliefs about good teaching in an academic day release medical education program: a qualitative study.

    PubMed

    van Roermund, Thea A C M; Mokkink, Henk G; Bottema, Ben J A M; van Weel, Chris; Scherpbier, Albert J J A

    2014-10-03

    In a professional learner-centered(ness) educational environment, communication and alignment of expectations about teaching are indispensable. Professional education of residents could benefit from an analysis and comparison of teachers' and residents' educational expectations and beliefs. Our purpose is to identify success factors and barriers related to aligning expectations and beliefs and building a supportive professional learner-centered educational environment. We conducted semi-structured individual interviews with teachers and semi-structured focus groups with residents. A single interview format was used to make it possible to compare the results. Data were analysed using a qualitative software package (AtlasTi). Data analysis steps were followed by the author team, which identified four domains of good teaching: personal traits, knowledge, relationships and teaching qualities. Teachers and residents agreed about the importance of personal professional characteristics like being a role model and having an open and enthusiastic attitude. They all thought that having a specific knowledge base was essential for teaching. Approaching residents as adult learners was found to be an important element of the learner-centred environment and it was agreed that teachers should take practical experiences to a higher level. However, teachers and residents had different expectations about the practical consequences of being a role model, adult learning, coaching and openness, and the type of knowledge that was needed in the professional development program. Communication about different expectations appeared to be difficult. Teachers and residents agreed on a conceptual level about expectations and beliefs regarding good teaching, but disagreed on an executive level. According to the residents, the disagreement about good teaching was not the biggest barrier to creating alignment and a supportive professional relationship; instead, it was the absence of a proper dialogue regarding issues about expectations and beliefs.

  14. Study of the May 2016 Seismic Swarm at Guadalajara, Jalisco, Mexico.

    NASA Astrophysics Data System (ADS)

    Nuñez-Cornu, F. J.; Reginfo, W.; Escalona-Alcazar, F. D. J.; Gutierrez Pena, Q. J.; Trejo-Gomez, E.; Suarez-Plascencia, C.; Nunez, D.

    2017-12-01

    The Metropolitan Zone of Guadalajara (MZG) is the second city of Mexico. This is a region with a high seismic hazard because there are historical reports of both large earthquakes and local seismic swarms. For this reason, it is important to evaluate and identify seismogenic structures that exist in the area. In order to assess the seismic hazard that this structures can represent both the population of the MZG and the facilities of the Geothermal Plant at Cerritos Colorados in La Primavera. In December of 2015 and in May of 2016 two seismic swarms occurred that affected the MZG. The May 2016 swarm was recorded by all stations of the Jalisco Telemetric Seismic and Accelerometric Network (RESAJ), preliminary locations estimated by the Antelope automatic system show an alignment of the earthquakes with an N-S trend west of the ZMG. The earthquakes were relocated, for which the phases were read and the Hypo71 program and a regional velocities model was used. The results allow us to observe two N-S alignments to the west of the MZG, the westernmost of which crosses La Caldera de la Primavera. The focal mechanisms of the earthquakes were calculated using the MecFor program with the Hypo71 outputs as input data. Most of the obtained mechanisms are mechanisms of normal fault with direction parallel to the alignments, suggesting the existence of two active faults that define a graben (graben of Zapopan). The lengths of these faults are 16 and 28 km indicating that they could generate earthquakes with magnitude 6.2 and 6.5, these earthquakes could cause great destruction in the MZG.

  15. ProBiS-database: precalculated binding site similarities and local pairwise alignments of PDB structures.

    PubMed

    Konc, Janez; Cesnik, Tomo; Konc, Joanna Trykowska; Penca, Matej; Janežič, Dušanka

    2012-02-27

    ProBiS-Database is a searchable repository of precalculated local structural alignments in proteins detected by the ProBiS algorithm in the Protein Data Bank. Identification of functionally important binding regions of the protein is facilitated by structural similarity scores mapped to the query protein structure. PDB structures that have been aligned with a query protein may be rapidly retrieved from the ProBiS-Database, which is thus able to generate hypotheses concerning the roles of uncharacterized proteins. Presented with uncharacterized protein structure, ProBiS-Database can discern relationships between such a query protein and other better known proteins in the PDB. Fast access and a user-friendly graphical interface promote easy exploration of this database of over 420 million local structural alignments. The ProBiS-Database is updated weekly and is freely available online at http://probis.cmm.ki.si/database.

  16. Understanding the Business Case for Telemental Health in Rural Communities.

    PubMed

    Lambert, David; Gale, John; Hartley, David; Croll, Zachariah; Hansen, Anush

    2016-07-01

    Telemental health has been promoted to address long-standing access barriers to rural mental health care, including low supply and long travel distances. Examples of rural telemental health programs are common; there is a less clear picture of how widely implemented these programs are, their organization, staffing, and services. There is also a need to understand the business case for these programs and assess whether and how they might realize their promise. To address these gaps, a national study was conducted of rural telemental health programs including an online survey of 53 programs and follow-up interviews with 23 programs. This article describes the current landscape and characteristics of these programs and then examines their business case. Can rural telemental health programs be sustained within current delivery systems and reimbursement structures? This question is explored in four areas: need and demand, infrastructure and workforce, funding and reimbursement, and organizational fit and alignment.

  17. Effects of scapular upward rotation exercises on alignment of scapula and clavicle and strength of scapular upward rotators in subjects with scapular downward rotation syndrome.

    PubMed

    Ha, Sung-min; Kwon, Oh-yun; Yi, Chung-hwi; Cynn, Heon-seock; Weon, Jong-hyuck; Kim, Tae-ho

    2016-02-01

    The purpose of this study was to investigate the effects of a 6-week scapular upward rotation exercise (SURE) on scapular and clavicular alignment and scapular upward rotators strength in subjects with scapular downward rotation syndrome (SDRS). Seventeen volunteer subjects with SDRS were recruited from university populations. The alignment of the scapula and clavicle was measured using radiographic analysis and compared in subjects before and after a 6-week self-SURE program. A hand-held dynamometer was used to measure the strength of the scapular upward rotators. The subjects were instructed how to perform the self-SURE program at home. The 6-week self-SURE program was divided into two sections (the first section with non-resistive SURE during weeks 1-3, and the second section with resistive SURE using thera-band during weeks 4-6). The significance of the difference between pre- and post-program was assessed using a paired t-test, with the level of statistical significance set at p<0.05. Significant differences between pre- and post-program were found for scapular and clavicular alignment (p<0.05). Additionally, the comparison between pre- and post-program measurements of the strength of the scapular upward rotators showed significant differences (p<0.05). The results of this study showed that a 6-week self-SURE program is effective for improving scapular and clavicular alignment and increasing the strength of scapular upward rotator muscles in subjects with SDRS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Genome alignment with graph data structures: a comparison

    PubMed Central

    2014-01-01

    Background Recent advances in rapid, low-cost sequencing have opened up the opportunity to study complete genome sequences. The computational approach of multiple genome alignment allows investigation of evolutionarily related genomes in an integrated fashion, providing a basis for downstream analyses such as rearrangement studies and phylogenetic inference. Graphs have proven to be a powerful tool for coping with the complexity of genome-scale sequence alignments. The potential of graphs to intuitively represent all aspects of genome alignments led to the development of graph-based approaches for genome alignment. These approaches construct a graph from a set of local alignments, and derive a genome alignment through identification and removal of graph substructures that indicate errors in the alignment. Results We compare the structures of commonly used graphs in terms of their abilities to represent alignment information. We describe how the graphs can be transformed into each other, and identify and classify graph substructures common to one or more graphs. Based on previous approaches, we compile a list of modifications that remove these substructures. Conclusion We show that crucial pieces of alignment information, associated with inversions and duplications, are not visible in the structure of all graphs. If we neglect vertex or edge labels, the graphs differ in their information content. Still, many ideas are shared among all graph-based approaches. Based on these findings, we outline a conceptual framework for graph-based genome alignment that can assist in the development of future genome alignment tools. PMID:24712884

  19. Optimal simultaneous superpositioning of multiple structures with missing data

    PubMed Central

    Theobald, Douglas L.; Steindel, Phillip A.

    2012-01-01

    Motivation: Superpositioning is an essential technique in structural biology that facilitates the comparison and analysis of conformational differences among topologically similar structures. Performing a superposition requires a one-to-one correspondence, or alignment, of the point sets in the different structures. However, in practice, some points are usually ‘missing’ from several structures, for example, when the alignment contains gaps. Current superposition methods deal with missing data simply by superpositioning a subset of points that are shared among all the structures. This practice is inefficient, as it ignores important data, and it fails to satisfy the common least-squares criterion. In the extreme, disregarding missing positions prohibits the calculation of a superposition altogether. Results: Here, we present a general solution for determining an optimal superposition when some of the data are missing. We use the expectation–maximization algorithm, a classic statistical technique for dealing with incomplete data, to find both maximum-likelihood solutions and the optimal least-squares solution as a special case. Availability and implementation: The methods presented here are implemented in THESEUS 2.0, a program for superpositioning macromolecular structures. ANSI C source code and selected compiled binaries for various computing platforms are freely available under the GNU open source license from http://www.theseus3d.org. Contact: dtheobald@brandeis.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:22543369

  20. Using Multimedia Metadata to Improve Network Efficiency

    DTIC Science & Technology

    2012-09-01

    the north-aligned bounding box. When compared using all angular variations for the direction-of-travel-aligned 3:4 aspect ratio bounding box, the...programs that run the experiment are written in Java . The experiment consists of two distinct programs that communicate via Java sockets (TCP). 1

  1. 77 FR 4239 - Sexual Assault Prevention and Response (SAPR) Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    .... Affected Public: Federal Government; Individuals or Households; Business or Other For-Profit; Not-For... General of the Military Departments and IG, DoD respectively. (2) Develop strategic program guidance...) Align Service SAPR Strategic Plans with the DoD SAPR Strategic Plan. (5) Align Service prevention...

  2. ModeRNA server: an online tool for modeling RNA 3D structures.

    PubMed

    Rother, Magdalena; Milanowska, Kaja; Puton, Tomasz; Jeleniewicz, Jaroslaw; Rother, Kristian; Bujnicki, Janusz M

    2011-09-01

    The diverse functional roles of non-coding RNA molecules are determined by their underlying structure. ModeRNA server is an online tool for RNA 3D structure modeling by the comparative approach, based on a template RNA structure and a user-defined target-template sequence alignment. It offers an option to search for potential templates, given the target sequence. The server also provides tools for analyzing, editing and formatting of RNA structure files. It facilitates the use of the ModeRNA software and offers new options in comparison to the standalone program. ModeRNA server was implemented using the Python language and the Django web framework. It is freely available at http://iimcb.genesilico.pl/modernaserver. iamb@genesilico.pl.

  3. Silicon Alignment Pins: An Easy Way to Realize a Wafer-To-Wafer Alignment

    NASA Technical Reports Server (NTRS)

    Peralta, Alejandro (Inventor); Gill, John J. (Inventor); Toda, Risaku (Inventor); Lin, Robert H. (Inventor); Jung-Kubiak, Cecile (Inventor); Reck, Theodore (Inventor); Thomas, Bertrand (Inventor); Siles, Jose V. (Inventor); Lee, Choonsup (Inventor); Chattopadhyay, Goutam (Inventor)

    2016-01-01

    A silicon alignment pin is used to align successive layers of components made in semiconductor chips and/or metallic components to make easier the assembly of devices having a layered structure. The pin is made as a compressible structure which can be squeezed to reduce its outer diameter, have one end fit into a corresponding alignment pocket or cavity defined in a layer of material to be assembled into a layered structure, and then allowed to expand to produce an interference fit with the cavity. The other end can then be inserted into a corresponding cavity defined in a surface of a second layer of material that mates with the first layer. The two layers are in registry when the pin is mated to both. Multiple layers can be assembled to create a multilayer structure. Examples of such devices are presented.

  4. Holistic Approach to Learning and Teaching Introductory Object-Oriented Programming

    ERIC Educational Resources Information Center

    Thota, Neena; Whitfield, Richard

    2010-01-01

    This article describes a holistic approach to designing an introductory, object-oriented programming course. The design is grounded in constructivism and pedagogy of phenomenography. We use constructive alignment as the framework to align assessments, learning, and teaching with planned learning outcomes. We plan learning and teaching activities,…

  5. Bellerophon: A program to detect chimeric sequences in multiple sequence alignments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huber, Thomas; Faulkner, Geoffrey; Hugenholtz, Philip

    2003-12-23

    Bellerophon is a program for detecting chimeric sequences in multiple sequence datasets by an adaption of partial treeing analysis. Bellerophon was specifically developed to detect 16S rRNA gene chimeras in PCR-clone libraries of environmental samples but can be applied to other nucleotide sequence alignments.

  6. Organizational Structure and Strategy. Symposium 30. [Concurrent Symposium Session at AHRD Annual Conference, 2000.

    ERIC Educational Resources Information Center

    2000

    This packet contains four papers on organizational structure and strategy from a symposium on human resource development (HRD). The first paper, "Exploring Alignment: A Comparative Case Study of Alignment in Two Organizations" (Steven W. Semler), reports on a case study that compared the results of an alignment measurement instrument…

  7. Minimap2: pairwise alignment for nucleotide sequences.

    PubMed

    Li, Heng

    2018-05-10

    Recent advances in sequencing technologies promise ultra-long reads of ∼100 kilo bases (kb) in average, full-length mRNA or cDNA reads in high throughput and genomic contigs over 100 mega bases (Mb) in length. Existing alignment programs are unable or inefficient to process such data at scale, which presses for the development of new alignment algorithms. Minimap2 is a general-purpose alignment program to map DNA or long mRNA sequences against a large reference database. It works with accurate short reads of ≥ 100bp in length, ≥1kb genomic reads at error rate ∼15%, full-length noisy Direct RNA or cDNA reads, and assembly contigs or closely related full chromosomes of hundreds of megabases in length. Minimap2 does split-read alignment, employs concave gap cost for long insertions and deletions (INDELs) and introduces new heuristics to reduce spurious alignments. It is 3-4 times as fast as mainstream short-read mappers at comparable accuracy, and is ≥30 times faster than long-read genomic or cDNA mappers at higher accuracy, surpassing most aligners specialized in one type of alignment. https://github.com/lh3/minimap2. hengli@broadinstitute.org.

  8. Fast and accurate phylogeny reconstruction using filtered spaced-word matches

    PubMed Central

    Sohrabi-Jahromi, Salma; Morgenstern, Burkhard

    2017-01-01

    Abstract Motivation: Word-based or ‘alignment-free’ algorithms are increasingly used for phylogeny reconstruction and genome comparison, since they are much faster than traditional approaches that are based on full sequence alignments. Existing alignment-free programs, however, are less accurate than alignment-based methods. Results: We propose Filtered Spaced Word Matches (FSWM), a fast alignment-free approach to estimate phylogenetic distances between large genomic sequences. For a pre-defined binary pattern of match and don’t-care positions, FSWM rapidly identifies spaced word-matches between input sequences, i.e. gap-free local alignments with matching nucleotides at the match positions and with mismatches allowed at the don’t-care positions. We then estimate the number of nucleotide substitutions per site by considering the nucleotides aligned at the don’t-care positions of the identified spaced-word matches. To reduce the noise from spurious random matches, we use a filtering procedure where we discard all spaced-word matches for which the overall similarity between the aligned segments is below a threshold. We show that our approach can accurately estimate substitution frequencies even for distantly related sequences that cannot be analyzed with existing alignment-free methods; phylogenetic trees constructed with FSWM distances are of high quality. A program run on a pair of eukaryotic genomes of a few hundred Mb each takes a few minutes. Availability and Implementation: The program source code for FSWM including a documentation, as well as the software that we used to generate artificial genome sequences are freely available at http://fswm.gobics.de/ Contact: chris.leimeister@stud.uni-goettingen.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28073754

  9. Fast and accurate phylogeny reconstruction using filtered spaced-word matches.

    PubMed

    Leimeister, Chris-André; Sohrabi-Jahromi, Salma; Morgenstern, Burkhard

    2017-04-01

    Word-based or 'alignment-free' algorithms are increasingly used for phylogeny reconstruction and genome comparison, since they are much faster than traditional approaches that are based on full sequence alignments. Existing alignment-free programs, however, are less accurate than alignment-based methods. We propose Filtered Spaced Word Matches (FSWM) , a fast alignment-free approach to estimate phylogenetic distances between large genomic sequences. For a pre-defined binary pattern of match and don't-care positions, FSWM rapidly identifies spaced word-matches between input sequences, i.e. gap-free local alignments with matching nucleotides at the match positions and with mismatches allowed at the don't-care positions. We then estimate the number of nucleotide substitutions per site by considering the nucleotides aligned at the don't-care positions of the identified spaced-word matches. To reduce the noise from spurious random matches, we use a filtering procedure where we discard all spaced-word matches for which the overall similarity between the aligned segments is below a threshold. We show that our approach can accurately estimate substitution frequencies even for distantly related sequences that cannot be analyzed with existing alignment-free methods; phylogenetic trees constructed with FSWM distances are of high quality. A program run on a pair of eukaryotic genomes of a few hundred Mb each takes a few minutes. The program source code for FSWM including a documentation, as well as the software that we used to generate artificial genome sequences are freely available at http://fswm.gobics.de/. chris.leimeister@stud.uni-goettingen.de. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

  10. Heuristic reusable dynamic programming: efficient updates of local sequence alignment.

    PubMed

    Hong, Changjin; Tewfik, Ahmed H

    2009-01-01

    Recomputation of the previously evaluated similarity results between biological sequences becomes inevitable when researchers realize errors in their sequenced data or when the researchers have to compare nearly similar sequences, e.g., in a family of proteins. We present an efficient scheme for updating local sequence alignments with an affine gap model. In principle, using the previous matching result between two amino acid sequences, we perform a forward-backward alignment to generate heuristic searching bands which are bounded by a set of suboptimal paths. Given a correctly updated sequence, we initially predict a new score of the alignment path for each contour to select the best candidates among them. Then, we run the Smith-Waterman algorithm in this confined space. Furthermore, our heuristic alignment for an updated sequence shows that it can be further accelerated by using reusable dynamic programming (rDP), our prior work. In this study, we successfully validate "relative node tolerance bound" (RNTB) in the pruned searching space. Furthermore, we improve the computational performance by quantifying the successful RNTB tolerance probability and switch to rDP on perturbation-resilient columns only. In our searching space derived by a threshold value of 90 percent of the optimal alignment score, we find that 98.3 percent of contours contain correctly updated paths. We also find that our method consumes only 25.36 percent of the runtime cost of sparse dynamic programming (sDP) method, and to only 2.55 percent of that of a normal dynamic programming with the Smith-Waterman algorithm.

  11. Automated batch fiducial-less tilt-series alignment in Appion using Protomo

    PubMed Central

    Noble, Alex J.; Stagg, Scott M.

    2015-01-01

    The field of electron tomography has benefited greatly from manual and semi-automated approaches to marker-based tilt-series alignment that have allowed for the structural determination of multitudes of in situ cellular structures as well as macromolecular structures of individual protein complexes. The emergence of complementary metal-oxide semiconductor detectors capable of detecting individual electrons has enabled the collection of low dose, high contrast images, opening the door for reliable correlation-based tilt-series alignment. Here we present a set of automated, correlation-based tilt-series alignment, contrast transfer function (CTF) correction, and reconstruction workflows for use in conjunction with the Appion/Leginon package that are primarily targeted at automating structure determination with cryogenic electron microscopy. PMID:26455557

  12. Anisotropic piezoresistivity characteristics of aligned carbon nanotube-polymer nanocomposites

    NASA Astrophysics Data System (ADS)

    Sengezer, Engin C.; Seidel, Gary D.; Bodnar, Robert J.

    2017-09-01

    Dielectrophoresis under the application of AC electric fields is one of the primary fabrication techniques for obtaining aligned carbon nanotube (CNT)-polymer nanocomposites, and is used here to generate long range alignment of CNTs at the structural level. The degree of alignment of CNTs within this long range architecture is observed via polarized Raman spectroscopy so that its influence on the electrical conductivity and piezoresistive response in both the alignment and transverse to alignment directions can be assessed. Nanocomposite samples consisting of randomly oriented, well dispersed single-wall carbon nanotubes (SWCNTs) and of long range electric field aligned SWCNTs in a photopolymerizable monomer blend (urethane dimethacrylate and 1,6-hexanediol dimethacrylate) are quantitatively and qualitatively evaluated. Piezoresistive sensitivities in form of gauge factors were measured for randomly oriented, well dispersed specimens with 0.03, 0.1 and 0.5 wt% SWCNTs and compared with gauge factors in both the axial and transverse to SWCNT alignment directions for electric field aligned 0.03 wt% specimens under both quasi-static monotonic and cyclic tensile loading. Gauge factors in the axial direction were observed to be on the order of 2, while gauge factors in the transverse direction demonstrated a 5 fold increase with values on the order of 10 for aligned specimens. Based on Raman analysis, it is believed the higher sensitivity of the transverse direction is related to architectural evolution of misaligned bridging structures which connect alignment structures under load due to Poisson’s contraction.

  13. DR-TAMAS: Diffeomorphic Registration for Tensor Accurate alignMent of Anatomical Structures

    PubMed Central

    Irfanoglu, M. Okan; Nayak, Amritha; Jenkins, Jeffrey; Hutchinson, Elizabeth B.; Sadeghi, Neda; Thomas, Cibu P.; Pierpaoli, Carlo

    2016-01-01

    In this work, we propose DR-TAMAS (Diffeomorphic Registration for Tensor Accurate alignMent of Anatomical Structures), a novel framework for intersubject registration of Diffusion Tensor Imaging (DTI) data sets. This framework is optimized for brain data and its main goal is to achieve an accurate alignment of all brain structures, including white matter (WM), gray matter (GM), and spaces containing cerebrospinal fluid (CSF). Currently most DTI-based spatial normalization algorithms emphasize alignment of anisotropic structures. While some diffusion-derived metrics, such as diffusion anisotropy and tensor eigenvector orientation, are highly informative for proper alignment of WM, other tensor metrics such as the trace or mean diffusivity (MD) are fundamental for a proper alignment of GM and CSF boundaries. Moreover, it is desirable to include information from structural MRI data, e.g., T1-weighted or T2-weighted images, which are usually available together with the diffusion data. The fundamental property of DR-TAMAS is to achieve global anatomical accuracy by incorporating in its cost function the most informative metrics locally. Another important feature of DR-TAMAS is a symmetric time-varying velocity-based transformation model, which enables it to account for potentially large anatomical variability in healthy subjects and patients. The performance of DR-TAMAS is evaluated with several data sets and compared with other widely-used diffeomorphic image registration techniques employing both full tensor information and/or DTI-derived scalar maps. Our results show that the proposed method has excellent overall performance in the entire brain, while being equivalent to the best existing methods in WM. PMID:26931817

  14. Precision alignment device

    DOEpatents

    Jones, N.E.

    1988-03-10

    Apparatus for providing automatic alignment of beam devices having an associated structure for directing, collimating, focusing, reflecting, or otherwise modifying the main beam. A reference laser is attached to the structure enclosing the main beam producing apparatus and produces a reference beam substantially parallel to the main beam. Detector modules containing optical switching devices and optical detectors are positioned in the path of the reference beam and are effective to produce an electrical output indicative of the alignment of the main beam. This electrical output drives servomotor operated adjustment screws to adjust the position of elements of the structure associated with the main beam to maintain alignment of the main beam. 5 figs.

  15. Precision alignment device

    DOEpatents

    Jones, Nelson E.

    1990-01-01

    Apparatus for providing automatic alignment of beam devices having an associated structure for directing, collimating, focusing, reflecting, or otherwise modifying the main beam. A reference laser is attached to the structure enclosing the main beam producing apparatus and produces a reference beam substantially parallel to the main beam. Detector modules containing optical switching devices and optical detectors are positioned in the path of the reference beam and are effective to produce an electrical output indicative of the alignment of the main beam. This electrical output drives servomotor operated adjustment screws to adjust the position of elements of the structure associated with the main beam to maintain alignment of the main beam.

  16. Desktop aligner for fabrication of multilayer microfluidic devices.

    PubMed

    Li, Xiang; Yu, Zeta Tak For; Geraldo, Dalton; Weng, Shinuo; Alve, Nitesh; Dun, Wu; Kini, Akshay; Patel, Karan; Shu, Roberto; Zhang, Feng; Li, Gang; Jin, Qinghui; Fu, Jianping

    2015-07-01

    Multilayer assembly is a commonly used technique to construct multilayer polydimethylsiloxane (PDMS)-based microfluidic devices with complex 3D architecture and connectivity for large-scale microfluidic integration. Accurate alignment of structure features on different PDMS layers before their permanent bonding is critical in determining the yield and quality of assembled multilayer microfluidic devices. Herein, we report a custom-built desktop aligner capable of both local and global alignments of PDMS layers covering a broad size range. Two digital microscopes were incorporated into the aligner design to allow accurate global alignment of PDMS structures up to 4 in. in diameter. Both local and global alignment accuracies of the desktop aligner were determined to be about 20 μm cm(-1). To demonstrate its utility for fabrication of integrated multilayer PDMS microfluidic devices, we applied the desktop aligner to achieve accurate alignment of different functional PDMS layers in multilayer microfluidics including an organs-on-chips device as well as a microfluidic device integrated with vertical passages connecting channels located in different PDMS layers. Owing to its convenient operation, high accuracy, low cost, light weight, and portability, the desktop aligner is useful for microfluidic researchers to achieve rapid and accurate alignment for generating multilayer PDMS microfluidic devices.

  17. Desktop aligner for fabrication of multilayer microfluidic devices

    PubMed Central

    Li, Xiang; Yu, Zeta Tak For; Geraldo, Dalton; Weng, Shinuo; Alve, Nitesh; Dun, Wu; Kini, Akshay; Patel, Karan; Shu, Roberto; Zhang, Feng; Li, Gang; Jin, Qinghui; Fu, Jianping

    2015-01-01

    Multilayer assembly is a commonly used technique to construct multilayer polydimethylsiloxane (PDMS)-based microfluidic devices with complex 3D architecture and connectivity for large-scale microfluidic integration. Accurate alignment of structure features on different PDMS layers before their permanent bonding is critical in determining the yield and quality of assembled multilayer microfluidic devices. Herein, we report a custom-built desktop aligner capable of both local and global alignments of PDMS layers covering a broad size range. Two digital microscopes were incorporated into the aligner design to allow accurate global alignment of PDMS structures up to 4 in. in diameter. Both local and global alignment accuracies of the desktop aligner were determined to be about 20 μm cm−1. To demonstrate its utility for fabrication of integrated multilayer PDMS microfluidic devices, we applied the desktop aligner to achieve accurate alignment of different functional PDMS layers in multilayer microfluidics including an organs-on-chips device as well as a microfluidic device integrated with vertical passages connecting channels located in different PDMS layers. Owing to its convenient operation, high accuracy, low cost, light weight, and portability, the desktop aligner is useful for microfluidic researchers to achieve rapid and accurate alignment for generating multilayer PDMS microfluidic devices. PMID:26233409

  18. Interactive software tool to comprehend the calculation of optimal sequence alignments with dynamic programming.

    PubMed

    Ibarra, Ignacio L; Melo, Francisco

    2010-07-01

    Dynamic programming (DP) is a general optimization strategy that is successfully used across various disciplines of science. In bioinformatics, it is widely applied in calculating the optimal alignment between pairs of protein or DNA sequences. These alignments form the basis of new, verifiable biological hypothesis. Despite its importance, there are no interactive tools available for training and education on understanding the DP algorithm. Here, we introduce an interactive computer application with a graphical interface, for the purpose of educating students about DP. The program displays the DP scoring matrix and the resulting optimal alignment(s), while allowing the user to modify key parameters such as the values in the similarity matrix, the sequence alignment algorithm version and the gap opening/extension penalties. We hope that this software will be useful to teachers and students of bioinformatics courses, as well as researchers who implement the DP algorithm for diverse applications. The software is freely available at: http:/melolab.org/sat. The software is written in the Java computer language, thus it runs on all major platforms and operating systems including Windows, Mac OS X and LINUX. All inquiries or comments about this software should be directed to Francisco Melo at fmelo@bio.puc.cl.

  19. Phylogenetic Characterization of Transport Protein Superfamilies: Superiority of SuperfamilyTree Programs over Those Based on Multiple Alignments

    PubMed Central

    Chen, Jonathan S.; Reddy, Vamsee; Chen, Joshua H.; Shlykov, Maksim A.; Zheng, Wei Hao; Cho, Jaehoon; Yen, Ming Ren; Saier, Milton H.

    2012-01-01

    Transport proteins function in the translocation of ions, solutes and macromolecules across cellular and organellar membranes. These integral membrane proteins fall into >600 families as tabulated in the Transporter Classification Database (www.tcdb.org). Recent studies, some of which are reported here, define distant phylogenetic relationships between families with the creation of superfamilies. Several of these are analyzed using a novel set of programs designed to allow reliable prediction of phylogenetic trees when sequence divergence is too great to allow the use of multiple alignments. These new programs, called SuperfamilyTree1 and 2 (SFT1 and 2), allow display of protein and family relationships, respectively, based on thousands of comparative BLAST scores rather than multiple alignments. Superfamilies analyzed include: (1) Aerolysins, (2) RTX Toxins, (3) Defensins, (4) Ion Transporters, (5) Bile/Arsenite/Riboflavin Transporters, (6) Cation: Proton Antiporters, and (7) the Glucose/Fructose/Lactose superfamily within the prokaryotic phosphoenol pyruvate-dependent Phosphotransferase System. In addition to defining the phylogenetic relationships of the proteins and families within these seven superfamilies, evidence is provided showing that the SFT programs outperform programs that are based on multiple alignments whenever sequence divergence of superfamily members is extensive. The SFT programs should be applicable to virtually any superfamily of proteins or nucleic acids. PMID:22286036

  20. CORAL: aligning conserved core regions across domain families.

    PubMed

    Fong, Jessica H; Marchler-Bauer, Aron

    2009-08-01

    Homologous protein families share highly conserved sequence and structure regions that are frequent targets for comparative analysis of related proteins and families. Many protein families, such as the curated domain families in the Conserved Domain Database (CDD), exhibit similar structural cores. To improve accuracy in aligning such protein families, we propose a profile-profile method CORAL that aligns individual core regions as gap-free units. CORAL computes optimal local alignment of two profiles with heuristics to preserve continuity within core regions. We benchmarked its performance on curated domains in CDD, which have pre-defined core regions, against COMPASS, HHalign and PSI-BLAST, using structure superpositions and comprehensive curator-optimized alignments as standards of truth. CORAL improves alignment accuracy on core regions over general profile methods, returning a balanced score of 0.57 for over 80% of all domain families in CDD, compared with the highest balanced score of 0.45 from other methods. Further, CORAL provides E-values to aid in detecting homologous protein families and, by respecting block boundaries, produces alignments with improved 'readability' that facilitate manual refinement. CORAL will be included in future versions of the NCBI Cn3D/CDTree software, which can be downloaded at http://www.ncbi.nlm.nih.gov/Structure/cdtree/cdtree.shtml. Supplementary data are available at Bioinformatics online.

  1. Building Strategically Aligned Individualized Education Programs for Transition

    ERIC Educational Resources Information Center

    Flannery, K. Brigid; Hellemn, Lisa A.

    2015-01-01

    The Individualized Education Programs (IEPs) for students 16 years of age or above must address specific transition components. Studies to date have focused on the presence and quality of these transition components, yet the alignment of these components and their role in leading the development of the IEP is just as critical. This qualitative…

  2. An Analysis of Gateway Technical College Instructors' Opinions on Secondary and Postsecondary Program Alignment

    ERIC Educational Resources Information Center

    Albrecht, Bryan D.

    2011-01-01

    The purpose of this study was to determine what opinions Gateway Technical College instructors had toward secondary and postsecondary program alignment. Student transition is critical to supporting the mission and vision of Gateway Technical College. The impetus for this study was twofold. First, the quality improvement process established at…

  3. Multiple DNA and protein sequence alignment on a workstation and a supercomputer.

    PubMed

    Tajima, K

    1988-11-01

    This paper describes a multiple alignment method using a workstation and supercomputer. The method is based on the alignment of a set of aligned sequences with the new sequence, and uses a recursive procedure of such alignment. The alignment is executed in a reasonable computation time on diverse levels from a workstation to a supercomputer, from the viewpoint of alignment results and computational speed by parallel processing. The application of the algorithm is illustrated by several examples of multiple alignment of 12 amino acid and DNA sequences of HIV (human immunodeficiency virus) env genes. Colour graphic programs on a workstation and parallel processing on a supercomputer are discussed.

  4. LIMAO: Cross-platform software for simulating laser-induced alignment and orientation dynamics of linear-, symmetric- and asymmetric tops

    NASA Astrophysics Data System (ADS)

    Szidarovszky, Tamás; Jono, Maho; Yamanouchi, Kaoru

    2018-07-01

    A user-friendly and cross-platform software called Laser-Induced Molecular Alignment and Orientation simulator (LIMAO) has been developed. The program can be used to simulate within the rigid rotor approximation the rotational dynamics of gas phase molecules induced by linearly polarized intense laser fields at a given temperature. The software is implemented in the Java and Mathematica programming languages. The primary aim of LIMAO is to aid experimental scientists in predicting and analyzing experimental data representing laser-induced spatial alignment and orientation of molecules.

  5. Huddle-coaching: a dynamic intervention for trainees and staff to support team-based care.

    PubMed

    Shunk, Rebecca; Dulay, Maya; Chou, Calvin L; Janson, Susan; O'Brien, Bridget C

    2014-02-01

    Many outpatient clinics where health professionals train will transition to a team-based medical home model over the next several years. Therefore, training programs need innovative approaches to prepare and incorporate trainees into team-based delivery systems. To address this need, educators at the San Francisco Veterans Affairs (VA) Medical Center included trainees in preclinic team "huddles," or briefing meetings to facilitate care coordination, and developed an interprofessional huddle-coaching program for nurse practitioner students and internal medicine residents who function as primary providers for patient panels in VA outpatient primary care clinics. The program aimed to support trainees' partnerships with staff and full participation in the VA's Patient Aligned Care Teams. The huddle-coaching program focuses on structuring the huddle process via scheduling, checklists, and designated huddle coaches; building relationships among team members through team-building activities; and teaching core skills to support collaborative practice. A multifaceted evaluation of the program showed positive results. Participants rated training sessions and team-building activities favorably. In interviews, trainees valued their team members and identified improvements in efficiency and quality of patient care as a result of the team-based approach. Huddle checklists and scores on the Team Development Measure indicated progress in team processes and relationships as the year progressed. These findings suggest that the huddle-coaching program was a worthwhile investment in trainee development that also supported the clinic's larger mission to deliver team-based, patient-aligned care. As more training sites shift to team-based care, the huddle-coaching program offers a strategy for successfully incorporating trainees.

  6. Introducing difference recurrence relations for faster semi-global alignment of long sequences.

    PubMed

    Suzuki, Hajime; Kasahara, Masahiro

    2018-02-19

    The read length of single-molecule DNA sequencers is reaching 1 Mb. Popular alignment software tools widely used for analyzing such long reads often take advantage of single-instruction multiple-data (SIMD) operations to accelerate calculation of dynamic programming (DP) matrices in the Smith-Waterman-Gotoh (SWG) algorithm with a fixed alignment start position at the origin. Nonetheless, 16-bit or 32-bit integers are necessary for storing the values in a DP matrix when sequences to be aligned are long; this situation hampers the use of the full SIMD width of modern processors. We proposed a faster semi-global alignment algorithm, "difference recurrence relations," that runs more rapidly than the state-of-the-art algorithm by a factor of 2.1. Instead of calculating and storing all the values in a DP matrix directly, our algorithm computes and stores mainly the differences between the values of adjacent cells in the matrix. Although the SWG algorithm and our algorithm can output exactly the same result, our algorithm mainly involves 8-bit integer operations, enabling us to exploit the full width of SIMD operations (e.g., 32) on modern processors. We also developed a library, libgaba, so that developers can easily integrate our algorithm into alignment programs. Our novel algorithm and optimized library implementation will facilitate accelerating nucleotide long-read analysis algorithms that use pairwise alignment stages. The library is implemented in the C programming language and available at https://github.com/ocxtal/libgaba .

  7. MUSCLE: multiple sequence alignment with high accuracy and high throughput.

    PubMed

    Edgar, Robert C

    2004-01-01

    We describe MUSCLE, a new computer program for creating multiple alignments of protein sequences. Elements of the algorithm include fast distance estimation using kmer counting, progressive alignment using a new profile function we call the log-expectation score, and refinement using tree-dependent restricted partitioning. The speed and accuracy of MUSCLE are compared with T-Coffee, MAFFT and CLUSTALW on four test sets of reference alignments: BAliBASE, SABmark, SMART and a new benchmark, PREFAB. MUSCLE achieves the highest, or joint highest, rank in accuracy on each of these sets. Without refinement, MUSCLE achieves average accuracy statistically indistinguishable from T-Coffee and MAFFT, and is the fastest of the tested methods for large numbers of sequences, aligning 5000 sequences of average length 350 in 7 min on a current desktop computer. The MUSCLE program, source code and PREFAB test data are freely available at http://www.drive5. com/muscle.

  8. Genetic Testing Registry

    MedlinePlus

    ... Splign Vector Alignment Search Tool (VAST) All Data & Software Resources... Domains & Structures BioSystems Cn3D Conserved Domain Database (CDD) Conserved Domain Search Service (CD Search) Structure (Molecular Modeling Database) Vector Alignment ...

  9. Automated batch fiducial-less tilt-series alignment in Appion using Protomo.

    PubMed

    Noble, Alex J; Stagg, Scott M

    2015-11-01

    The field of electron tomography has benefited greatly from manual and semi-automated approaches to marker-based tilt-series alignment that have allowed for the structural determination of multitudes of in situ cellular structures as well as macromolecular structures of individual protein complexes. The emergence of complementary metal-oxide semiconductor detectors capable of detecting individual electrons has enabled the collection of low dose, high contrast images, opening the door for reliable correlation-based tilt-series alignment. Here we present a set of automated, correlation-based tilt-series alignment, contrast transfer function (CTF) correction, and reconstruction workflows for use in conjunction with the Appion/Leginon package that are primarily targeted at automating structure determination with cryogenic electron microscopy. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Image fusion for visualization of hepatic vasculature and tumors

    NASA Astrophysics Data System (ADS)

    Chou, Jin-Shin; Chen, Shiuh-Yung J.; Sudakoff, Gary S.; Hoffmann, Kenneth R.; Chen, Chin-Tu; Dachman, Abraham H.

    1995-05-01

    We have developed segmentation and simultaneous display techniques to facilitate the visualization of the three-dimensional spatial relationships between organ structures and organ vasculature. We concentrate on the visualization of the liver based on spiral computed tomography images. Surface-based 3-D rendering and maximal intensity projection algorithms are used for data visualization. To extract the liver in the serial of images accurately and efficiently, we have developed a user-friendly interactive program with a deformable-model segmentation. Surface rendering techniques are used to visualize the extracted structures, adjacent contours are aligned and fitted with a Bezier surface to yield a smooth surface. Visualization of the vascular structures, portal and hepatic veins, is achieved by applying a MIP technique to the extracted liver volume. To integrate the extracted structures they are surface-rendered and their MIP images are aligned and a color table is designed for simultaneous display of the combined liver/tumor and vasculature images. By combining the 3-D surface rendering and MIP techniques, portal veins, hepatic veins, and hepatic tumor can be inspected simultaneously and their spatial relationships can be more easily perceived. The proposed technique will be useful for visualization of both hepatic neoplasm and vasculature in surgical planning for tumor resection or living-donor liver transplantation.

  11. On sufficient statistics of least-squares superposition of vector sets.

    PubMed

    Konagurthu, Arun S; Kasarapu, Parthan; Allison, Lloyd; Collier, James H; Lesk, Arthur M

    2015-06-01

    The problem of superposition of two corresponding vector sets by minimizing their sum-of-squares error under orthogonal transformation is a fundamental task in many areas of science, notably structural molecular biology. This problem can be solved exactly using an algorithm whose time complexity grows linearly with the number of correspondences. This efficient solution has facilitated the widespread use of the superposition task, particularly in studies involving macromolecular structures. This article formally derives a set of sufficient statistics for the least-squares superposition problem. These statistics are additive. This permits a highly efficient (constant time) computation of superpositions (and sufficient statistics) of vector sets that are composed from its constituent vector sets under addition or deletion operation, where the sufficient statistics of the constituent sets are already known (that is, the constituent vector sets have been previously superposed). This results in a drastic improvement in the run time of the methods that commonly superpose vector sets under addition or deletion operations, where previously these operations were carried out ab initio (ignoring the sufficient statistics). We experimentally demonstrate the improvement our work offers in the context of protein structural alignment programs that assemble a reliable structural alignment from well-fitting (substructural) fragment pairs. A C++ library for this task is available online under an open-source license.

  12. SANSparallel: interactive homology search against Uniprot

    PubMed Central

    Somervuo, Panu; Holm, Liisa

    2015-01-01

    Proteins evolve by mutations and natural selection. The network of sequence similarities is a rich source for mining homologous relationships that inform on protein structure and function. There are many servers available to browse the network of homology relationships but one has to wait up to a minute for results. The SANSparallel webserver provides protein sequence database searches with immediate response and professional alignment visualization by third-party software. The output is a list, pairwise alignment or stacked alignment of sequence-similar proteins from Uniprot, UniRef90/50, Swissprot or Protein Data Bank. The stacked alignments are viewed in Jalview or as sequence logos. The database search uses the suffix array neighborhood search (SANS) method, which has been re-implemented as a client-server, improved and parallelized. The method is extremely fast and as sensitive as BLAST above 50% sequence identity. Benchmarks show that the method is highly competitive compared to previously published fast database search programs: UBLAST, DIAMOND, LAST, LAMBDA, RAPSEARCH2 and BLAT. The web server can be accessed interactively or programmatically at http://ekhidna2.biocenter.helsinki.fi/cgi-bin/sans/sans.cgi. It can be used to make protein functional annotation pipelines more efficient, and it is useful in interactive exploration of the detailed evidence supporting the annotation of particular proteins of interest. PMID:25855811

  13. Comparative Analysis of the Measurement of Total Instructional Alignment

    ERIC Educational Resources Information Center

    Kick, Laura C.

    2013-01-01

    In 2007, Lisa Carter created the Total Instructional Alignment system--a process that aligns standards, curriculum, assessment, and instruction. Employed in several hundred school systems, the TIA process is a successful professional development program. The researcher developed an instrument to measure the success of the TIA process with the…

  14. A Mathematical Optimization Problem in Bioinformatics

    ERIC Educational Resources Information Center

    Heyer, Laurie J.

    2008-01-01

    This article describes the sequence alignment problem in bioinformatics. Through examples, we formulate sequence alignment as an optimization problem and show how to compute the optimal alignment with dynamic programming. The examples and sample exercises have been used by the author in a specialized course in bioinformatics, but could be adapted…

  15. Diffeomorphic functional brain surface alignment: Functional demons.

    PubMed

    Nenning, Karl-Heinz; Liu, Hesheng; Ghosh, Satrajit S; Sabuncu, Mert R; Schwartz, Ernst; Langs, Georg

    2017-08-01

    Aligning brain structures across individuals is a central prerequisite for comparative neuroimaging studies. Typically, registration approaches assume a strong association between the features used for alignment, such as macro-anatomy, and the variable observed, such as functional activation or connectivity. Here, we propose to use the structure of intrinsic resting state fMRI signal correlation patterns as a basis for alignment of the cortex in functional studies. Rather than assuming the spatial correspondence of functional structures between subjects, we have identified locations with similar connectivity profiles across subjects. We mapped functional connectivity relationships within the brain into an embedding space, and aligned the resulting maps of multiple subjects. We then performed a diffeomorphic alignment of the cortical surfaces, driven by the corresponding features in the joint embedding space. Results show that functional alignment based on resting state fMRI identifies functionally homologous regions across individuals with higher accuracy than alignment based on the spatial correspondence of anatomy. Further, functional alignment enables measurement of the strength of the anatomo-functional link across the cortex, and reveals the uneven distribution of this link. Stronger anatomo-functional dissociation was found in higher association areas compared to primary sensory- and motor areas. Functional alignment based on resting state features improves group analysis of task based functional MRI data, increasing statistical power and improving the delineation of task-specific core regions. Finally, a comparison of the anatomo-functional dissociation between cohorts is demonstrated with a group of left and right handed subjects. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Dali server update.

    PubMed

    Holm, Liisa; Laakso, Laura M

    2016-07-08

    The Dali server (http://ekhidna2.biocenter.helsinki.fi/dali) is a network service for comparing protein structures in 3D. In favourable cases, comparing 3D structures may reveal biologically interesting similarities that are not detectable by comparing sequences. The Dali server has been running in various places for over 20 years and is used routinely by crystallographers on newly solved structures. The latest update of the server provides enhanced analytics for the study of sequence and structure conservation. The server performs three types of structure comparisons: (i) Protein Data Bank (PDB) search compares one query structure against those in the PDB and returns a list of similar structures; (ii) pairwise comparison compares one query structure against a list of structures specified by the user; and (iii) all against all structure comparison returns a structural similarity matrix, a dendrogram and a multidimensional scaling projection of a set of structures specified by the user. Structural superimpositions are visualized using the Java-free WebGL viewer PV. The structural alignment view is enhanced by sequence similarity searches against Uniprot. The combined structure-sequence alignment information is compressed to a stack of aligned sequence logos. In the stack, each structure is structurally aligned to the query protein and represented by a sequence logo. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. PF2fit: Polar Fast Fourier Matched Alignment of Atomistic Structures with 3D Electron Microscopy Maps.

    PubMed

    Bettadapura, Radhakrishna; Rasheed, Muhibur; Vollrath, Antje; Bajaj, Chandrajit

    2015-10-01

    There continue to be increasing occurrences of both atomistic structure models in the PDB (possibly reconstructed from X-ray diffraction or NMR data), and 3D reconstructed cryo-electron microscopy (3D EM) maps (albeit at coarser resolution) of the same or homologous molecule or molecular assembly, deposited in the EMDB. To obtain the best possible structural model of the molecule at the best achievable resolution, and without any missing gaps, one typically aligns (match and fits) the atomistic structure model with the 3D EM map. We discuss a new algorithm and generalized framework, named PF(2) fit (Polar Fast Fourier Fitting) for the best possible structural alignment of atomistic structures with 3D EM. While PF(2) fit enables only a rigid, six dimensional (6D) alignment method, it augments prior work on 6D X-ray structure and 3D EM alignment in multiple ways: Scoring. PF(2) fit includes a new scoring scheme that, in addition to rewarding overlaps between the volumes occupied by the atomistic structure and 3D EM map, rewards overlaps between the volumes complementary to them. We quantitatively demonstrate how this new complementary scoring scheme improves upon existing approaches. PF(2) fit also includes two scoring functions, the non-uniform exterior penalty and the skeleton-secondary structure score, and implements the scattering potential score as an alternative to traditional Gaussian blurring. Search. PF(2) fit utilizes a fast polar Fourier search scheme, whose main advantage is the ability to search over uniformly and adaptively sampled subsets of the space of rigid-body motions. PF(2) fit also implements a new reranking search and scoring methodology that considerably improves alignment metrics in results obtained from the initial search.

  18. PF2 fit: Polar Fast Fourier Matched Alignment of Atomistic Structures with 3D Electron Microscopy Maps

    PubMed Central

    Bettadapura, Radhakrishna; Rasheed, Muhibur; Vollrath, Antje; Bajaj, Chandrajit

    2015-01-01

    There continue to be increasing occurrences of both atomistic structure models in the PDB (possibly reconstructed from X-ray diffraction or NMR data), and 3D reconstructed cryo-electron microscopy (3D EM) maps (albeit at coarser resolution) of the same or homologous molecule or molecular assembly, deposited in the EMDB. To obtain the best possible structural model of the molecule at the best achievable resolution, and without any missing gaps, one typically aligns (match and fits) the atomistic structure model with the 3D EM map. We discuss a new algorithm and generalized framework, named PF2 fit (Polar Fast Fourier Fitting) for the best possible structural alignment of atomistic structures with 3D EM. While PF2 fit enables only a rigid, six dimensional (6D) alignment method, it augments prior work on 6D X-ray structure and 3D EM alignment in multiple ways: Scoring. PF2 fit includes a new scoring scheme that, in addition to rewarding overlaps between the volumes occupied by the atomistic structure and 3D EM map, rewards overlaps between the volumes complementary to them. We quantitatively demonstrate how this new complementary scoring scheme improves upon existing approaches. PF2 fit also includes two scoring functions, the non-uniform exterior penalty and the skeleton-secondary structure score, and implements the scattering potential score as an alternative to traditional Gaussian blurring. Search. PF2 fit utilizes a fast polar Fourier search scheme, whose main advantage is the ability to search over uniformly and adaptively sampled subsets of the space of rigid-body motions. PF2 fit also implements a new reranking search and scoring methodology that considerably improves alignment metrics in results obtained from the initial search. PMID:26469938

  19. National Center for Biotechnology Information

    MedlinePlus

    ... Splign Vector Alignment Search Tool (VAST) All Data & Software Resources... Domains & Structures BioSystems Cn3D Conserved Domain Database (CDD) Conserved Domain Search Service (CD Search) Structure (Molecular Modeling Database) Vector Alignment ...

  20. MANGO: a new approach to multiple sequence alignment.

    PubMed

    Zhang, Zefeng; Lin, Hao; Li, Ming

    2007-01-01

    Multiple sequence alignment is a classical and challenging task for biological sequence analysis. The problem is NP-hard. The full dynamic programming takes too much time. The progressive alignment heuristics adopted by most state of the art multiple sequence alignment programs suffer from the 'once a gap, always a gap' phenomenon. Is there a radically new way to do multiple sequence alignment? This paper introduces a novel and orthogonal multiple sequence alignment method, using multiple optimized spaced seeds and new algorithms to handle these seeds efficiently. Our new algorithm processes information of all sequences as a whole, avoiding problems caused by the popular progressive approaches. Because the optimized spaced seeds are provably significantly more sensitive than the consecutive k-mers, the new approach promises to be more accurate and reliable. To validate our new approach, we have implemented MANGO: Multiple Alignment with N Gapped Oligos. Experiments were carried out on large 16S RNA benchmarks showing that MANGO compares favorably, in both accuracy and speed, against state-of-art multiple sequence alignment methods, including ClustalW 1.83, MUSCLE 3.6, MAFFT 5.861, Prob-ConsRNA 1.11, Dialign 2.2.1, DIALIGN-T 0.2.1, T-Coffee 4.85, POA 2.0 and Kalign 2.0.

  1. Simplification May Not Be So Simple: Gauging State Alignment with the FAFSA

    ERIC Educational Resources Information Center

    Pingel, Sarah

    2017-01-01

    Applying for financial aid can be a complicated, time-consuming endeavor for students and their families. Fortunately, many state aid programs have taken strides to align aid applications to the form used for federal aid programs, the Free Application for Federal Student Aid (FAFSA), making state aid more readily accessible. New conversations…

  2. A hybrid short read mapping accelerator

    PubMed Central

    2013-01-01

    Background The rapid growth of short read datasets poses a new challenge to the short read mapping problem in terms of sensitivity and execution speed. Existing methods often use a restrictive error model for computing the alignments to improve speed, whereas more flexible error models are generally too slow for large-scale applications. A number of short read mapping software tools have been proposed. However, designs based on hardware are relatively rare. Field programmable gate arrays (FPGAs) have been successfully used in a number of specific application areas, such as the DSP and communications domains due to their outstanding parallel data processing capabilities, making them a competitive platform to solve problems that are “inherently parallel”. Results We present a hybrid system for short read mapping utilizing both FPGA-based hardware and CPU-based software. The computation intensive alignment and the seed generation operations are mapped onto an FPGA. We present a computationally efficient, parallel block-wise alignment structure (Align Core) to approximate the conventional dynamic programming algorithm. The performance is compared to the multi-threaded CPU-based GASSST and BWA software implementations. For single-end alignment, our hybrid system achieves faster processing speed than GASSST (with a similar sensitivity) and BWA (with a higher sensitivity); for pair-end alignment, our design achieves a slightly worse sensitivity than that of BWA but has a higher processing speed. Conclusions This paper shows that our hybrid system can effectively accelerate the mapping of short reads to a reference genome based on the seed-and-extend approach. The performance comparison to the GASSST and BWA software implementations under different conditions shows that our hybrid design achieves a high degree of sensitivity and requires less overall execution time with only modest FPGA resource utilization. Our hybrid system design also shows that the performance bottleneck for the short read mapping problem can be changed from the alignment stage to the seed generation stage, which provides an additional requirement for the future development of short read aligners. PMID:23441908

  3. A statistical physics perspective on alignment-independent protein sequence comparison.

    PubMed

    Chattopadhyay, Amit K; Nasiev, Diar; Flower, Darren R

    2015-08-01

    Within bioinformatics, the textual alignment of amino acid sequences has long dominated the determination of similarity between proteins, with all that implies for shared structure, function and evolutionary descent. Despite the relative success of modern-day sequence alignment algorithms, so-called alignment-free approaches offer a complementary means of determining and expressing similarity, with potential benefits in certain key applications, such as regression analysis of protein structure-function studies, where alignment-base similarity has performed poorly. Here, we offer a fresh, statistical physics-based perspective focusing on the question of alignment-free comparison, in the process adapting results from 'first passage probability distribution' to summarize statistics of ensemble averaged amino acid propensity values. In this article, we introduce and elaborate this approach. © The Author 2015. Published by Oxford University Press.

  4. Protein docking by the interface structure similarity: how much structure is needed?

    PubMed

    Sinha, Rohita; Kundrotas, Petras J; Vakser, Ilya A

    2012-01-01

    The increasing availability of co-crystallized protein-protein complexes provides an opportunity to use template-based modeling for protein-protein docking. Structure alignment techniques are useful in detection of remote target-template similarities. The size of the structure involved in the alignment is important for the success in modeling. This paper describes a systematic large-scale study to find the optimal definition/size of the interfaces for the structure alignment-based docking applications. The results showed that structural areas corresponding to the cutoff values <12 Å across the interface inadequately represent structural details of the interfaces. With the increase of the cutoff beyond 12 Å, the success rate for the benchmark set of 99 protein complexes, did not increase significantly for higher accuracy models, and decreased for lower-accuracy models. The 12 Å cutoff was optimal in our interface alignment-based docking, and a likely best choice for the large-scale (e.g., on the scale of the entire genome) applications to protein interaction networks. The results provide guidelines for the docking approaches, including high-throughput applications to modeled structures.

  5. SeqFIRE: a web application for automated extraction of indel regions and conserved blocks from protein multiple sequence alignments.

    PubMed

    Ajawatanawong, Pravech; Atkinson, Gemma C; Watson-Haigh, Nathan S; Mackenzie, Bryony; Baldauf, Sandra L

    2012-07-01

    Analyses of multiple sequence alignments generally focus on well-defined conserved sequence blocks, while the rest of the alignment is largely ignored or discarded. This is especially true in phylogenomics, where large multigene datasets are produced through automated pipelines. However, some of the most powerful phylogenetic markers have been found in the variable length regions of multiple alignments, particularly insertions/deletions (indels) in protein sequences. We have developed Sequence Feature and Indel Region Extractor (SeqFIRE) to enable the automated identification and extraction of indels from protein sequence alignments. The program can also extract conserved blocks and identify fast evolving sites using a combination of conservation and entropy. All major variables can be adjusted by the user, allowing them to identify the sets of variables most suited to a particular analysis or dataset. Thus, all major tasks in preparing an alignment for further analysis are combined in a single flexible and user-friendly program. The output includes a numbered list of indels, alignments in NEXUS format with indels annotated or removed and indel-only matrices. SeqFIRE is a user-friendly web application, freely available online at www.seqfire.org/.

  6. A dynamic programming approach for the alignment of signal peaks in multiple gas chromatography-mass spectrometry experiments.

    PubMed

    Robinson, Mark D; De Souza, David P; Keen, Woon Wai; Saunders, Eleanor C; McConville, Malcolm J; Speed, Terence P; Likić, Vladimir A

    2007-10-29

    Gas chromatography-mass spectrometry (GC-MS) is a robust platform for the profiling of certain classes of small molecules in biological samples. When multiple samples are profiled, including replicates of the same sample and/or different sample states, one needs to account for retention time drifts between experiments. This can be achieved either by the alignment of chromatographic profiles prior to peak detection, or by matching signal peaks after they have been extracted from chromatogram data matrices. Automated retention time correction is particularly important in non-targeted profiling studies. A new approach for matching signal peaks based on dynamic programming is presented. The proposed approach relies on both peak retention times and mass spectra. The alignment of more than two peak lists involves three steps: (1) all possible pairs of peak lists are aligned, and similarity of each pair of peak lists is estimated; (2) the guide tree is built based on the similarity between the peak lists; (3) peak lists are progressively aligned starting with the two most similar peak lists, following the guide tree until all peak lists are exhausted. When two or more experiments are performed on different sample states and each consisting of multiple replicates, peak lists within each set of replicate experiments are aligned first (within-state alignment), and subsequently the resulting alignments are aligned themselves (between-state alignment). When more than two sets of replicate experiments are present, the between-state alignment also employs the guide tree. We demonstrate the usefulness of this approach on GC-MS metabolic profiling experiments acquired on wild-type and mutant Leishmania mexicana parasites. We propose a progressive method to match signal peaks across multiple GC-MS experiments based on dynamic programming. A sensitive peak similarity function is proposed to balance peak retention time and peak mass spectra similarities. This approach can produce the optimal alignment between an arbitrary number of peak lists, and models explicitly within-state and between-state peak alignment. The accuracy of the proposed method was close to the accuracy of manually-curated peak matching, which required tens of man-hours for the analyzed data sets. The proposed approach may offer significant advantages for processing of high-throughput metabolomics data, especially when large numbers of experimental replicates and multiple sample states are analyzed.

  7. Hyperfine-Structure-Induced Depolarization of Impulsively Aligned I2 Molecules

    NASA Astrophysics Data System (ADS)

    Thomas, Esben F.; Søndergaard, Anders A.; Shepperson, Benjamin; Henriksen, Niels E.; Stapelfeldt, Henrik

    2018-04-01

    A moderately intense 450 fs laser pulse is used to create rotational wave packets in gas phase I2 molecules. The ensuing time-dependent alignment, measured by Coulomb explosion imaging with a delayed probe pulse, exhibits the characteristic revival structures expected for rotational wave packets but also a complex nonperiodic substructure and decreasing mean alignment not observed before. A quantum mechanical model attributes the phenomena to coupling between the rotational angular momenta and the nuclear spins through the electric quadrupole interaction. The calculated alignment trace agrees very well with the experimental results.

  8. Motorized Beam Alignment of a Commercial X-ray Diffractometer

    NASA Technical Reports Server (NTRS)

    Van Zandt, Noah R.; Myers, James F.; Rogers, Richard B

    2013-01-01

    X-ray diffraction (XRD) is a powerful analysis method that allows researchers to noninvasively probe the crystalline structure of a material. This includes the ability to determine the crystalline phases present, quantify surface residual stresses, and measure the distribution of crystallographic orientations. The Structures and Materials Division at the NASA Glenn Research Center (GRC) heavily uses the on-site XRD lab to characterize advanced metal alloys, ceramics, and polymers. One of the x-ray diffractometers in the XRD lab (Bruker D8 Discover) uses three different x-ray tubes (Cu, Cr, and Mn) for optimal performance over numerous material types and various experimental techniques. This requires that the tubes be switched out and aligned between experiments. This alignment maximizes the x-ray tube s output through an iterative process involving four set screws. However, the output of the x-ray tube cannot be monitored during the adjustment process due to standard radiation safety engineering controls that prevent exposure to the x-ray beam when the diffractometer doors are open. Therefore, the adjustment process is a very tedious series of blind adjustments, each followed by measurement of the output beam using a PIN diode after the enclosure doors are shut. This process can take up to 4 hr to perform. This technical memorandum documents an in-house project to motorize this alignment process. Unlike a human, motors are not harmed by x-ray radiation of the energy range used in this instrument. Therefore, using motors to adjust the set screws will allow the researcher to monitor the x-ray tube s output while making interactive adjustments from outside the diffractometer. The motorized alignment system consists of four motors, a motor controller, and a hand-held user interface module. Our goal was to reduce the alignment time to less than 30 min. The time available was the 10-week span of the Lewis' Educational and Research Collaborative Internship Project (LERCIP) summer internship program and the budget goal was $1200. In this report, we will describe our motorization design and discuss the results of its implementation.

  9. Multi-subject Manifold Alignment of Functional Network Structures via Joint Diagonalization.

    PubMed

    Nenning, Karl-Heinz; Kollndorfer, Kathrin; Schöpf, Veronika; Prayer, Daniela; Langs, Georg

    2015-01-01

    Functional magnetic resonance imaging group studies rely on the ability to establish correspondence across individuals. This enables location specific comparison of functional brain characteristics. Registration is often based on morphology and does not take variability of functional localization into account. This can lead to a loss of specificity, or confounds when studying diseases. In this paper we propose multi-subject functional registration by manifold alignment via coupled joint diagonalization. The functional network structure of each subject is encoded in a diffusion map, where functional relationships are decoupled from spatial position. Two-step manifold alignment estimates initial correspondences between functionally equivalent regions. Then, coupled joint diagonalization establishes common eigenbases across all individuals, and refines the functional correspondences. We evaluate our approach on fMRI data acquired during a language paradigm. Experiments demonstrate the benefits in matching accuracy achieved by coupled joint diagonalization compared to previously proposed functional alignment approaches, or alignment based on structural correspondences.

  10. Aligning physician and hospital incentives: the approach at hospital for special surgery.

    PubMed

    Ranawat, Anil S; Koenig, Jonathan H; Thomas, Adrian J; Krna, Catherine D; Shapiro, Louis A

    2009-10-01

    Healthcare administrators and physicians alike are navigating an increasingly complex and highly regulated healthcare environment. Unlike in the past, institutions now require strong collaboration among physician and administrative leaders. As providers and managers are trained and work differently, new methods are needed to provide the infrastructure and resources necessary to create, nurture, and sustain alignment between them. We describe four initiatives by administrators and physicians at Hospital for Special Surgery to work together in mutually beneficial relationships that help us achieve the highest level of patient care, satisfaction and safety. These initiatives include improving management efficiency through an orthopaedic service line structure, helping individual physicians grow their practices through the demand-office-operating room initiative of the Physicians Service Department, controlling costs through the supply effectiveness policy, and promoting teamwork in innovation through the technology transfer program.

  11. General study of asymmetrical crossed Czerny-Turner spectrometer.

    PubMed

    Tang, Ming; Fan, Xianguang; Wang, Xin; Xu, Yingjie; Que, Jing; He, Jian

    2015-11-20

    A study of the spectrum resolution, wavelength range, and primary aberration of the asymmetrical crossed Czerny-Turner spectrometer is presented by deducing the relationship between them and structural parameters of the spectrometer in a new way of thinking based on simple but effective geometric models. The analysis was verified in an experiment and simulation performed on the optical design program ZEMAX, and the obtained results agree with the analysis. Owing to the analysis, initial designed parameters of the spectrometer were given and then optimized by ZEMAX; with the instruction of the study, a small adjustment was made in the actual alignment to obtain the desired final spectrometer. The spectrometer successfully measured the last four characteristic peaks of the Raman spectrum of CCL4, which demonstrates that the research provides important guidance to the design and alignment of an asymmetrical crossed Czerny-Turner spectrometer.

  12. Rigid Amorphous Fraction in PLA Electrospun Fibers

    NASA Astrophysics Data System (ADS)

    Cebe, Peggy; Ma, Qian; Simona Cozza, Erika; Pyda, Marek; Mao, Bin; Zhu, Yazhe; Monticelli, Orietta

    2013-03-01

    Electrospun fibers of poly(lactic acid) (PLA) were formed by adopting a high-speed rotating wheel as the counter-electrode. The molecular orientation, crystallization mechanism, and phase structure and transitions of the aligned ES fibers were investigated. Using thermal analysis and wide angle X-ray scattering (WAXS), we evaluated the confinement that exists in as-spun amorphous, and heat-treated semicrystalline, fibers. Differential scanning calorimetry confirmed the existence of a constrained amorphous phase in as-spun aligned fibers, without the presence of crystals or fillers to serve as fixed physical constraints. Using WAXS, for the first time the mesophase fraction, consisting of oriented amorphous PLA chains, was quantitatively characterized in nanofibers. The authors acknowledge support from the National Science Foundation, Polymers Program under grant DMR-0602473. ESC acknowledges a Ph.D. grant supported by Italian Ministry of Education and Scientific Research.

  13. Generic accelerated sequence alignment in SeqAn using vectorization and multi-threading.

    PubMed

    Rahn, René; Budach, Stefan; Costanza, Pascal; Ehrhardt, Marcel; Hancox, Jonny; Reinert, Knut

    2018-05-03

    Pairwise sequence alignment is undoubtedly a central tool in many bioinformatics analyses. In this paper, we present a generically accelerated module for pairwise sequence alignments applicable for a broad range of applications. In our module, we unified the standard dynamic programming kernel used for pairwise sequence alignments and extended it with a generalized inter-sequence vectorization layout, such that many alignments can be computed simultaneously by exploiting SIMD (Single Instruction Multiple Data) instructions of modern processors. We then extended the module by adding two layers of thread-level parallelization, where we a) distribute many independent alignments on multiple threads and b) inherently parallelize a single alignment computation using a work stealing approach producing a dynamic wavefront progressing along the minor diagonal. We evaluated our alignment vectorization and parallelization on different processors, including the newest Intel® Xeon® (Skylake) and Intel® Xeon Phi™ (KNL) processors, and use cases. The instruction set AVX512-BW (Byte and Word), available on Skylake processors, can genuinely improve the performance of vectorized alignments. We could run single alignments 1600 times faster on the Xeon Phi™ and 1400 times faster on the Xeon® than executing them with our previous sequential alignment module. The module is programmed in C++ using the SeqAn (Reinert et al., 2017) library and distributed with version 2.4. under the BSD license. We support SSE4, AVX2, AVX512 instructions and included UME::SIMD, a SIMD-instruction wrapper library, to extend our module for further instruction sets. We thoroughly test all alignment components with all major C++ compilers on various platforms. rene.rahn@fu-berlin.de.

  14. Student Expectations, University Goals: Looking for Alignment in General Education Science

    ERIC Educational Resources Information Center

    Ericson, Rebecca J.

    2012-01-01

    This action research dissertation explores the alignment of university goals, faculty practice, and student expectations for general education natural science courses as a first step to understanding how best to restructure the program to ensure that students are learning in alignment with university stated goals for this aspect of their…

  15. RNA-TVcurve: a Web server for RNA secondary structure comparison based on a multi-scale similarity of its triple vector curve representation.

    PubMed

    Li, Ying; Shi, Xiaohu; Liang, Yanchun; Xie, Juan; Zhang, Yu; Ma, Qin

    2017-01-21

    RNAs have been found to carry diverse functionalities in nature. Inferring the similarity between two given RNAs is a fundamental step to understand and interpret their functional relationship. The majority of functional RNAs show conserved secondary structures, rather than sequence conservation. Those algorithms relying on sequence-based features usually have limitations in their prediction performance. Hence, integrating RNA structure features is very critical for RNA analysis. Existing algorithms mainly fall into two categories: alignment-based and alignment-free. The alignment-free algorithms of RNA comparison usually have lower time complexity than alignment-based algorithms. An alignment-free RNA comparison algorithm was proposed, in which novel numerical representations RNA-TVcurve (triple vector curve representation) of RNA sequence and corresponding secondary structure features are provided. Then a multi-scale similarity score of two given RNAs was designed based on wavelet decomposition of their numerical representation. In support of RNA mutation and phylogenetic analysis, a web server (RNA-TVcurve) was designed based on this alignment-free RNA comparison algorithm. It provides three functional modules: 1) visualization of numerical representation of RNA secondary structure; 2) detection of single-point mutation based on secondary structure; and 3) comparison of pairwise and multiple RNA secondary structures. The inputs of the web server require RNA primary sequences, while corresponding secondary structures are optional. For the primary sequences alone, the web server can compute the secondary structures using free energy minimization algorithm in terms of RNAfold tool from Vienna RNA package. RNA-TVcurve is the first integrated web server, based on an alignment-free method, to deliver a suite of RNA analysis functions, including visualization, mutation analysis and multiple RNAs structure comparison. The comparison results with two popular RNA comparison tools, RNApdist and RNAdistance, showcased that RNA-TVcurve can efficiently capture subtle relationships among RNAs for mutation detection and non-coding RNA classification. All the relevant results were shown in an intuitive graphical manner, and can be freely downloaded from this server. RNA-TVcurve, along with test examples and detailed documents, are available at: http://ml.jlu.edu.cn/tvcurve/ .

  16. DR-TAMAS: Diffeomorphic Registration for Tensor Accurate Alignment of Anatomical Structures.

    PubMed

    Irfanoglu, M Okan; Nayak, Amritha; Jenkins, Jeffrey; Hutchinson, Elizabeth B; Sadeghi, Neda; Thomas, Cibu P; Pierpaoli, Carlo

    2016-05-15

    In this work, we propose DR-TAMAS (Diffeomorphic Registration for Tensor Accurate alignMent of Anatomical Structures), a novel framework for intersubject registration of Diffusion Tensor Imaging (DTI) data sets. This framework is optimized for brain data and its main goal is to achieve an accurate alignment of all brain structures, including white matter (WM), gray matter (GM), and spaces containing cerebrospinal fluid (CSF). Currently most DTI-based spatial normalization algorithms emphasize alignment of anisotropic structures. While some diffusion-derived metrics, such as diffusion anisotropy and tensor eigenvector orientation, are highly informative for proper alignment of WM, other tensor metrics such as the trace or mean diffusivity (MD) are fundamental for a proper alignment of GM and CSF boundaries. Moreover, it is desirable to include information from structural MRI data, e.g., T1-weighted or T2-weighted images, which are usually available together with the diffusion data. The fundamental property of DR-TAMAS is to achieve global anatomical accuracy by incorporating in its cost function the most informative metrics locally. Another important feature of DR-TAMAS is a symmetric time-varying velocity-based transformation model, which enables it to account for potentially large anatomical variability in healthy subjects and patients. The performance of DR-TAMAS is evaluated with several data sets and compared with other widely-used diffeomorphic image registration techniques employing both full tensor information and/or DTI-derived scalar maps. Our results show that the proposed method has excellent overall performance in the entire brain, while being equivalent to the best existing methods in WM. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. COS NUV Target Acquisition Monitor

    NASA Astrophysics Data System (ADS)

    Penton, Steven V.

    2017-08-01

    Visits PA, BA, & BB of this program verify all ACQ/IMAGE mode co-alignments by bootstrapping from PSA+MIRRORA. The assumption, which should be tested at some point, is that the PSA+MIRRORA WCA-to-PSA FSW offsets are still as accurate in defining the center of the PSA relative to the WCA as there were in SMOV. The details of the observations are given is the observing section.Visit PB was an on-hold contingency visit in case, for whatever reason, visit 2A of 14452, did not execute as planned in the fall of 2017. This program was replaced with a better program for aligning the FGGs so we needed to activate this visit to obtain the PSA/MIRRORA to PSA/MIRRORB ACQ/IMAGE alignment. Visit BA of this program takes back-to-back PSA/MIRRORB & BOA/MIRRORA ACQ/Images and images (with flashes) and also takes G230L, G285M as well as FUV LP3 G130M and G140L spectra to test the WCA-to-PSA offsets.Visit BB of this program takes back-to-back BOA/MIRRORA & BOA/MIRRORB ACQ/Images and images (with flashes) and also takes G225M, G185M, and FUV LP3 G160M spectra to test the WCA-to-PSA offsets. Visit BA of this program bootstraps off VIsit PB to co-align the PSA+MIRRORB ACQ/IMAGE mode to the BOA+MIRRORA. Visit BB of this program follows the style of Visit BA and bootstraps from the BOA+MIRRORA mode to the BOA+MIRRORB TA imaging mode. In all visits, lamp+target images are taken before and after the TA imaging mode that is being co-aligned (the second ACQ/IMAGE of the program.)All visits in this program are single orbit visits. This program is very similar to the NUV portion of the C24 version (14857). This program differs from the Cycle 23 version in that Visit PB (the old Visit 03) has been permanently upgraded from contingency to operational status. NOTE: Beginning with Cycle 25. ALL FUV exposures in this program have been moved to a separate monitoring program. This program will sequentially test the XD accuracy of FUV LP4 spectra. As needed, NUV ACQ/IMAGEs will reset the centering between grating tests.

  18. Artificial Aurora Generated by HAARP (Invited)

    NASA Astrophysics Data System (ADS)

    Streltsov, A. V.; Kendall, E. A.

    2013-12-01

    We present results from the ionospheric heating experiment conducted on March 12, 2013 at the High Frequency Active Auroral Research Program (HAARP) facility in Alaska. During the experiment HAARP transmitted X-mode 4.57 MHz waves modulated with the frequency 0.9 mHz and pointed in the direction of the magnetic zenith. The beam was focused to ~20 km spot at the altitude 100 km. The heating produces two effects: First, it generates magnetic field-aligned currents producing D and H components of the magnetic field with frequency 0.9 mHz detected by fluxgate magnetometer in Gakona. Second, the heating produced bright luminous structures in the heated region detected with the SRI telescope in 427.8 nm, 557.7 nm, 630.0 nm wavelengths. We emphasize, that for the best of our knowledge, this is the first experiment where the heating of the ionosphere with X-mode produces luminous structures in the ionosphere. We classify this luminosity as an 'artificial aurora', because it correlate with the intensity of the magnetic field-aligned currents, and such correlation is constantly seen in the natural aurora.

  19. Reexamining X-mode suppression and fine structure in artificial E region field-aligned plasma density irregularities

    NASA Astrophysics Data System (ADS)

    Miceli, R. J.; Hysell, D. L.; Munk, J.; McCarrick, M.; Huba, J. D.

    2013-09-01

    Artificial field-aligned plasma density irregularities (FAIs) were generated in the E region of the ionosphere above the High Frequency Active Auroral Research Program facility during campaigns in May and August of 2012 and observed using a 30 MHz coherent scatter radar imager in Homer, Alaska. The purpose of this ionospheric modification experiment was to measure the threshold pump power required to excite thermal parametric instabilities by O-mode heating and to investigate the suppression of the FAIs by simultaneous X-mode heating. We find that the threshold pump power for irregularity excitation was consistent with theoretical predictions and increased by approximately a factor of 2 when X-mode heating was present. A modified version of the Another Model of the Ionosphere (SAMI2) ionospheric model was used to simulate the threshold experiments and suggested that the increase was entirely due to enhanced D region absorption associated with X-mode heating. Additionally, a remarkable degree of fine structure possibly caused by natural gradient drift instability in the heater-modified volume was observed in experiments performed during geomagnetically active conditions.

  20. XML schemas for common bioinformatic data types and their application in workflow systems

    PubMed Central

    Seibel, Philipp N; Krüger, Jan; Hartmeier, Sven; Schwarzer, Knut; Löwenthal, Kai; Mersch, Henning; Dandekar, Thomas; Giegerich, Robert

    2006-01-01

    Background Today, there is a growing need in bioinformatics to combine available software tools into chains, thus building complex applications from existing single-task tools. To create such workflows, the tools involved have to be able to work with each other's data – therefore, a common set of well-defined data formats is needed. Unfortunately, current bioinformatic tools use a great variety of heterogeneous formats. Results Acknowledging the need for common formats, the Helmholtz Open BioInformatics Technology network (HOBIT) identified several basic data types used in bioinformatics and developed appropriate format descriptions, formally defined by XML schemas, and incorporated them in a Java library (BioDOM). These schemas currently cover sequence, sequence alignment, RNA secondary structure and RNA secondary structure alignment formats in a form that is independent of any specific program, thus enabling seamless interoperation of different tools. All XML formats are available at , the BioDOM library can be obtained at . Conclusion The HOBIT XML schemas and the BioDOM library simplify adding XML support to newly created and existing bioinformatic tools, enabling these tools to interoperate seamlessly in workflow scenarios. PMID:17087823

  1. Identifying functionally informative evolutionary sequence profiles.

    PubMed

    Gil, Nelson; Fiser, Andras

    2018-04-15

    Multiple sequence alignments (MSAs) can provide essential input to many bioinformatics applications, including protein structure prediction and functional annotation. However, the optimal selection of sequences to obtain biologically informative MSAs for such purposes is poorly explored, and has traditionally been performed manually. We present Selection of Alignment by Maximal Mutual Information (SAMMI), an automated, sequence-based approach to objectively select an optimal MSA from a large set of alternatives sampled from a general sequence database search. The hypothesis of this approach is that the mutual information among MSA columns will be maximal for those MSAs that contain the most diverse set possible of the most structurally and functionally homogeneous protein sequences. SAMMI was tested to select MSAs for functional site residue prediction by analysis of conservation patterns on a set of 435 proteins obtained from protein-ligand (peptides, nucleic acids and small substrates) and protein-protein interaction databases. Availability and implementation: A freely accessible program, including source code, implementing SAMMI is available at https://github.com/nelsongil92/SAMMI.git. andras.fiser@einstein.yu.edu. Supplementary data are available at Bioinformatics online.

  2. Temporal Effects of Alignment in Text-Based, Task-Oriented Discourse

    ERIC Educational Resources Information Center

    Foltz, Anouschka; Gaspers, Judith; Meyer, Carolin; Thiele, Kristina; Cimiano, Philipp; Stenneken, Prisca

    2015-01-01

    Communicative alignment refers to adaptation to one's communication partner. Temporal aspects of such alignment have been little explored. This article examines temporal aspects of lexical and syntactic alignment (i.e., tendencies to use the interlocutor's lexical items and syntactic structures) in task-oriented discourse. In particular, we…

  3. Object-oriented sequence analysis: SCL--a C++ class library.

    PubMed

    Vahrson, W; Hermann, K; Kleffe, J; Wittig, B

    1996-04-01

    SCL (Sequence Class Library) is a class library written in the C++ programming language. Designed using object-oriented programming principles, SCL consists of classes of objects performing tasks typically needed for analyzing DNA or protein sequences. Among them are very flexible sequence classes, classes accessing databases in various formats, classes managing collections of sequences, as well as classes performing higher-level tasks like calculating a pairwise sequence alignment. SCL also includes classes that provide general programming support, like a dynamically growing array, sets, matrices, strings, classes performing file input/output, and utilities for error handling. By providing these components, SCL fosters an explorative programming style: experimenting with algorithms and alternative implementations is encouraged rather than punished. A description of SCL's overall structure as well as an overview of its classes is given. Important aspects of the work with SCL are discussed in the context of a sample program.

  4. Secondary-structure matching (SSM), a new tool for fast protein structure alignment in three dimensions.

    PubMed

    Krissinel, E; Henrick, K

    2004-12-01

    The present paper describes the SSM algorithm of protein structure comparison in three dimensions, which includes an original procedure of matching graphs built on the protein's secondary-structure elements, followed by an iterative three-dimensional alignment of protein backbone Calpha atoms. The SSM results are compared with those obtained from other protein comparison servers, and the advantages and disadvantages of different scores that are used for structure recognition are discussed. A new score, balancing the r.m.s.d. and alignment length Nalign, is proposed. It is found that different servers agree reasonably well on the new score, while showing considerable differences in r.m.s.d. and Nalign.

  5. A Stochastic Evolutionary Model for Protein Structure Alignment and Phylogeny

    PubMed Central

    Challis, Christopher J.; Schmidler, Scott C.

    2012-01-01

    We present a stochastic process model for the joint evolution of protein primary and tertiary structure, suitable for use in alignment and estimation of phylogeny. Indels arise from a classic Links model, and mutations follow a standard substitution matrix, whereas backbone atoms diffuse in three-dimensional space according to an Ornstein–Uhlenbeck process. The model allows for simultaneous estimation of evolutionary distances, indel rates, structural drift rates, and alignments, while fully accounting for uncertainty. The inclusion of structural information enables phylogenetic inference on time scales not previously attainable with sequence evolution models. The model also provides a tool for testing evolutionary hypotheses and improving our understanding of protein structural evolution. PMID:22723302

  6. Career Pathways: Aligning Public Resources to Support Individual and Regional Economic Advancement in the Knowledge Economy

    ERIC Educational Resources Information Center

    Jenkins, Davis

    2006-01-01

    This paper describes career pathways, a framework or approach by which regions can better align publicly supported systems and programs to build a knowledge-economy workforce customized to the needs of local labor markets. A career pathway is a series of connected education and training programs and support services that enable individuals to…

  7. Parallel seed-based approach to multiple protein structure similarities detection

    DOE PAGES

    Chapuis, Guillaume; Le Boudic-Jamin, Mathilde; Andonov, Rumen; ...

    2015-01-01

    Finding similarities between protein structures is a crucial task in molecular biology. Most of the existing tools require proteins to be aligned in order-preserving way and only find single alignments even when multiple similar regions exist. We propose a new seed-based approach that discovers multiple pairs of similar regions. Its computational complexity is polynomial and it comes with a quality guarantee—the returned alignments have both root mean squared deviations (coordinate-based as well as internal-distances based) lower than a given threshold, if such exist. We do not require the alignments to be order preserving (i.e., we consider nonsequential alignments), which makesmore » our algorithm suitable for detecting similar domains when comparing multidomain proteins as well as to detect structural repetitions within a single protein. Because the search space for nonsequential alignments is much larger than for sequential ones, the computational burden is addressed by extensive use of parallel computing techniques: a coarse-grain level parallelism making use of available CPU cores for computation and a fine-grain level parallelism exploiting bit-level concurrency as well as vector instructions.« less

  8. Evidence for Syntactic Alignment in Children with Autism

    ERIC Educational Resources Information Center

    Allen, Melissa L.; Haywood, Sarah; Rajendran, Gnanathusharan; Branigan, Holly

    2011-01-01

    We report an experiment that examined whether children with Autistic Spectrum Disorder (ASD) spontaneously converge, or align, syntactic structure with a conversational partner. Children with ASD were more likely to produce a passive structure to describe a picture after hearing their interlocutor use a passive structure to describe an unrelated…

  9. Minerals and aligned collagen fibrils in tilapia fish scales: structural analysis using dark-field and energy-filtered transmission electron microscopy and electron tomography.

    PubMed

    Okuda, Mitsuhiro; Ogawa, Nobuhiro; Takeguchi, Masaki; Hashimoto, Ayako; Tagaya, Motohiro; Chen, Song; Hanagata, Nobutaka; Ikoma, Toshiyuki

    2011-10-01

    The mineralized structure of aligned collagen fibrils in a tilapia fish scale was investigated using transmission electron microscopy (TEM) techniques after a thin sample was prepared using aqueous techniques. Electron diffraction and electron energy loss spectroscopy data indicated that a mineralized internal layer consisting of aligned collagen fibrils contains hydroxyapatite crystals. Bright-field imaging, dark-field imaging, and energy-filtered TEM showed that the hydroxyapatite was mainly distributed in the hole zones of the aligned collagen fibrils structure, while needle-like materials composed of calcium compounds including hydroxyapatite existed in the mineralized internal layer. Dark-field imaging and three-dimensional observation using electron tomography revealed that hydroxyapatite and needle-like materials were mainly found in the matrix between the collagen fibrils. It was observed that hydroxyapatite and needle-like materials were preferentially distributed on the surface of the hole zones in the aligned collagen fibrils structure and in the matrix between the collagen fibrils in the mineralized internal layer of the scale.

  10. Aligning USGS senior leadership structure with the USGS science strategy

    USGS Publications Warehouse

    ,

    2010-01-01

    The U.S. Geological Survey (USGS) is realigning its management and budget structure to further enhance the work of its science programs and their interdisciplinary focus areas related to the USGS Science Strategy as outlined in 'Facing Tomorrow's Challenges-U.S. Geological Survey Science in the Decade 2007-2017' (U.S. Geological Survey, 2007). In 2007, the USGS developed this science strategy outlining major natural-science issues facing the Nation and focusing on areas where natural science can make a substantial contribution to the well being of the Nation and the world. These areas include global climate change, water resources, natural hazards, energy and minerals, ecosystems, and data integration.

  11. ASPIC: a novel method to predict the exon-intron structure of a gene that is optimally compatible to a set of transcript sequences.

    PubMed

    Bonizzoni, Paola; Rizzi, Raffaella; Pesole, Graziano

    2005-10-05

    Currently available methods to predict splice sites are mainly based on the independent and progressive alignment of transcript data (mostly ESTs) to the genomic sequence. Apart from often being computationally expensive, this approach is vulnerable to several problems--hence the need to develop novel strategies. We propose a method, based on a novel multiple genome-EST alignment algorithm, for the detection of splice sites. To avoid limitations of splice sites prediction (mainly, over-predictions) due to independent single EST alignments to the genomic sequence our approach performs a multiple alignment of transcript data to the genomic sequence based on the combined analysis of all available data. We recast the problem of predicting constitutive and alternative splicing as an optimization problem, where the optimal multiple transcript alignment minimizes the number of exons and hence of splice site observations. We have implemented a splice site predictor based on this algorithm in the software tool ASPIC (Alternative Splicing PredICtion). It is distinguished from other methods based on BLAST-like tools by the incorporation of entirely new ad hoc procedures for accurate and computationally efficient transcript alignment and adopts dynamic programming for the refinement of intron boundaries. ASPIC also provides the minimal set of non-mergeable transcript isoforms compatible with the detected splicing events. The ASPIC web resource is dynamically interconnected with the Ensembl and Unigene databases and also implements an upload facility. Extensive bench marking shows that ASPIC outperforms other existing methods in the detection of novel splicing isoforms and in the minimization of over-predictions. ASPIC also requires a lower computation time for processing a single gene and an EST cluster. The ASPIC web resource is available at http://aspic.algo.disco.unimib.it/aspic-devel/.

  12. Aligning for accountable care: Strategic practices for change in accountable care organizations.

    PubMed

    Hilligoss, Brian; Song, Paula H; McAlearney, Ann Scheck

    Alignment within accountable care organizations (ACOs) is crucial if these new entities are to achieve their lofty goals. However, the concept of alignment remains underexamined, and we know little about the work entailed in creating alignment. The aim of this study was to develop the concept of aligning by identifying and describing the strategic practices administrators use to align the structures, processes, and behaviors of their organizations and individual providers in pursuit of accountable care. We conducted 2-year qualitative case studies of four ACOs that have assumed full risk for the costs and quality of care for defined populations. Five strategic aligning practices were used by all four ACOs. Informing both aligns providers' understandings with the goals and value proposition of the ACO and aligns the providers' attention with the drivers of performance. Involving both aligns ACO leaders' understandings with the realities facing providers and aligns the policies of the ACO with the needs of providers. Enhancing both aligns the operations of individual provider practices with the operations of the ACO and aligns the trust of providers with the ACO. Motivating aligns what providers value with the goals of the ACO. Finally, evolving is a metapractice of learning and adapting that guides the execution of the other four practices. Our findings suggest that there are second-order cognitive (e.g., understandings and attention) and cultural (e.g., trust and values) levels of alignment, as well as a first-order operational level (organizational structures, processes, and incentives). A well-aligned organization may require ongoing repositioning at each of these levels, as well as attention to both cooperative and coordinative dimensions of alignment. Implications for research and practice are discussed.

  13. A short note on dynamic programming in a band.

    PubMed

    Gibrat, Jean-François

    2018-06-15

    Third generation sequencing technologies generate long reads that exhibit high error rates, in particular for insertions and deletions which are usually the most difficult errors to cope with. The only exact algorithm capable of aligning sequences with insertions and deletions is a dynamic programming algorithm. In this note, for the sake of efficiency, we consider dynamic programming in a band. We show how to choose the band width in function of the long reads' error rates, thus obtaining an [Formula: see text] algorithm in space and time. We also propose a procedure to decide whether this algorithm, when applied to semi-global alignments, provides the optimal score. We suggest that dynamic programming in a band is well suited to the problem of aligning long reads between themselves and can be used as a core component of methods for obtaining a consensus sequence from the long reads alone. The function implementing the dynamic programming algorithm in a band is available, as a standalone program, at: https://forgemia.inra.fr/jean-francois.gibrat/BAND_DYN_PROG.git.

  14. Layered magnetic structures: Antiferromagnetic-type interlayer coupling and magnetoresistance due to antiparallel alignment

    NASA Astrophysics Data System (ADS)

    Grünberg, P.; Demokritov, S.; Fuss, A.; Vohl, M.; Wolf, J. A.

    1991-04-01

    Layered Fe/Cr structures are known to display antiferromagnetic-type interlayer coupling and a new magnetoresistance (MR) effect due to antiparallel magnetization alignment. The strength of the coupling is found to be similar in multilayered structures and in double layers. The oscillatory behavior of the coupling, previously found by Parkin, More, and Roche [Phys. Rev. Lett. 64, 2304 (1990)] on sputtered polycrystalline samples, is here confirmed for epitaxial samples, obtained by thermal evaporation. The new MR effect is interpreted as due to a spin-dependent scattering of the electrons at the Fe-Cr interfaces. The investigations have been extended to Fe/V, Fe/Mn, Fe/Cu, Co/Au, Co/Cr, and Co/Cu structures where the antiparallel alignment of the ferromagnetic layers is obtained via hysteresis effects. A MR effect due to antiparallel alignment, which is strong for Co/Au and Co/Cu but weak in the other cases, has been found.

  15. Fusion bonding and alignment fixture

    DOEpatents

    Ackler, Harold D.; Swierkowski, Stefan P.; Tarte, Lisa A.; Hicks, Randall K.

    2000-01-01

    An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all the components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.

  16. Is Group Therapy Democratic? Enduring Consequences of Outward Bound's Alignment with the Human Potential Movement. A Response to "How to Be Nice and Get What You Want: Structural Referents of "Self" and "Other" in Experiential Education as (Un)Democratic Practice."

    ERIC Educational Resources Information Center

    Seaman, Jayson

    2016-01-01

    Franklin Vernon provided an example of how programs viewing themselves as "cultural islands" are in fact embedded within historical capitalist relations, through the discourses of "self" that they promote. In this response, I expand on Vernon's argument to situate the quasi-therapeutic practices he identified in the history of…

  17. Special Focus

    PubMed Central

    Nawrocki, Eric P.; Burge, Sarah W.

    2013-01-01

    The development of RNA bioinformatic tools began more than 30 y ago with the description of the Nussinov and Zuker dynamic programming algorithms for single sequence RNA secondary structure prediction. Since then, many tools have been developed for various RNA sequence analysis problems such as homology search, multiple sequence alignment, de novo RNA discovery, read-mapping, and many more. In this issue, we have collected a sampling of reviews and original research that demonstrate some of the many ways bioinformatics is integrated with current RNA biology research. PMID:23948768

  18. Kraken: ultrafast metagenomic sequence classification using exact alignments

    PubMed Central

    2014-01-01

    Kraken is an ultrafast and highly accurate program for assigning taxonomic labels to metagenomic DNA sequences. Previous programs designed for this task have been relatively slow and computationally expensive, forcing researchers to use faster abundance estimation programs, which only classify small subsets of metagenomic data. Using exact alignment of k-mers, Kraken achieves classification accuracy comparable to the fastest BLAST program. In its fastest mode, Kraken classifies 100 base pair reads at a rate of over 4.1 million reads per minute, 909 times faster than Megablast and 11 times faster than the abundance estimation program MetaPhlAn. Kraken is available at http://ccb.jhu.edu/software/kraken/. PMID:24580807

  19. Dynamic programming algorithms for biological sequence comparison.

    PubMed

    Pearson, W R; Miller, W

    1992-01-01

    Efficient dynamic programming algorithms are available for a broad class of protein and DNA sequence comparison problems. These algorithms require computer time proportional to the product of the lengths of the two sequences being compared [O(N2)] but require memory space proportional only to the sum of these lengths [O(N)]. Although the requirement for O(N2) time limits use of the algorithms to the largest computers when searching protein and DNA sequence databases, many other applications of these algorithms, such as calculation of distances for evolutionary trees and comparison of a new sequence to a library of sequence profiles, are well within the capabilities of desktop computers. In particular, the results of library searches with rapid searching programs, such as FASTA or BLAST, should be confirmed by performing a rigorous optimal alignment. Whereas rapid methods do not overlook significant sequence similarities, FASTA limits the number of gaps that can be inserted into an alignment, so that a rigorous alignment may extend the alignment substantially in some cases. BLAST does not allow gaps in the local regions that it reports; a calculation that allows gaps is very likely to extend the alignment substantially. Although a Monte Carlo evaluation of the statistical significance of a similarity score with a rigorous algorithm is much slower than the heuristic approach used by the RDF2 program, the dynamic programming approach should take less than 1 hr on a 386-based PC or desktop Unix workstation. For descriptive purposes, we have limited our discussion to methods for calculating similarity scores and distances that use gap penalties of the form g = rk. Nevertheless, programs for the more general case (g = q+rk) are readily available. Versions of these programs that run either on Unix workstations, IBM-PC class computers, or the Macintosh can be obtained from either of the authors.

  20. Implementing Strategic Orientation

    ERIC Educational Resources Information Center

    Fischer, Arthur K.; Brownback, Sarah

    2012-01-01

    An HRM case dealing with problems and issues of setting up orientation programs which align with corporate strategy. Discussion concerns how such a case can be used to exhibit the alignment between HRM and business strategy.

  1. The protein structure prediction problem could be solved using the current PDB library

    PubMed Central

    Zhang, Yang; Skolnick, Jeffrey

    2005-01-01

    For single-domain proteins, we examine the completeness of the structures in the current Protein Data Bank (PDB) library for use in full-length model construction of unknown sequences. To address this issue, we employ a comprehensive benchmark set of 1,489 medium-size proteins that cover the PDB at the level of 35% sequence identity and identify templates by structure alignment. With homologous proteins excluded, we can always find similar folds to native with an average rms deviation (RMSD) from native of 2.5 Å with ≈82% alignment coverage. These template structures often contain a significant number of insertions/deletions. The tasser algorithm was applied to build full-length models, where continuous fragments are excised from the top-scoring templates and reassembled under the guide of an optimized force field, which includes consensus restraints taken from the templates and knowledge-based statistical potentials. For almost all targets (except for 2/1,489), the resultant full-length models have an RMSD to native below 6 Å (97% of them below 4 Å). On average, the RMSD of full-length models is 2.25 Å, with aligned regions improved from 2.5 Å to 1.88 Å, comparable with the accuracy of low-resolution experimental structures. Furthermore, starting from state-of-the-art structural alignments, we demonstrate a methodology that can consistently bring template-based alignments closer to native. These results are highly suggestive that the protein-folding problem can in principle be solved based on the current PDB library by developing efficient fold recognition algorithms that can recover such initial alignments. PMID:15653774

  2. Cryo-EM image alignment based on nonuniform fast Fourier transform.

    PubMed

    Yang, Zhengfan; Penczek, Pawel A

    2008-08-01

    In single particle analysis, two-dimensional (2-D) alignment is a fundamental step intended to put into register various particle projections of biological macromolecules collected at the electron microscope. The efficiency and quality of three-dimensional (3-D) structure reconstruction largely depends on the computational speed and alignment accuracy of this crucial step. In order to improve the performance of alignment, we introduce a new method that takes advantage of the highly accurate interpolation scheme based on the gridding method, a version of the nonuniform fast Fourier transform, and utilizes a multi-dimensional optimization algorithm for the refinement of the orientation parameters. Using simulated data, we demonstrate that by using less than half of the sample points and taking twice the runtime, our new 2-D alignment method achieves dramatically better alignment accuracy than that based on quadratic interpolation. We also apply our method to image to volume registration, the key step in the single particle EM structure refinement protocol. We find that in this case the accuracy of the method not only surpasses the accuracy of the commonly used real-space implementation, but results are achieved in much shorter time, making gridding-based alignment a perfect candidate for efficient structure determination in single particle analysis.

  3. Cryo-EM Image Alignment Based on Nonuniform Fast Fourier Transform

    PubMed Central

    Yang, Zhengfan; Penczek, Pawel A.

    2008-01-01

    In single particle analysis, two-dimensional (2-D) alignment is a fundamental step intended to put into register various particle projections of biological macromolecules collected at the electron microscope. The efficiency and quality of three-dimensional (3-D) structure reconstruction largely depends on the computational speed and alignment accuracy of this crucial step. In order to improve the performance of alignment, we introduce a new method that takes advantage of the highly accurate interpolation scheme based on the gridding method, a version of the nonuniform Fast Fourier Transform, and utilizes a multi-dimensional optimization algorithm for the refinement of the orientation parameters. Using simulated data, we demonstrate that by using less than half of the sample points and taking twice the runtime, our new 2-D alignment method achieves dramatically better alignment accuracy than that based on quadratic interpolation. We also apply our method to image to volume registration, the key step in the single particle EM structure refinement protocol. We find that in this case the accuracy of the method not only surpasses the accuracy of the commonly used real-space implementation, but results are achieved in much shorter time, making gridding-based alignment a perfect candidate for efficient structure determination in single particle analysis. PMID:18499351

  4. Directions in parallel programming: HPF, shared virtual memory and object parallelism in pC++

    NASA Technical Reports Server (NTRS)

    Bodin, Francois; Priol, Thierry; Mehrotra, Piyush; Gannon, Dennis

    1994-01-01

    Fortran and C++ are the dominant programming languages used in scientific computation. Consequently, extensions to these languages are the most popular for programming massively parallel computers. We discuss two such approaches to parallel Fortran and one approach to C++. The High Performance Fortran Forum has designed HPF with the intent of supporting data parallelism on Fortran 90 applications. HPF works by asking the user to help the compiler distribute and align the data structures with the distributed memory modules in the system. Fortran-S takes a different approach in which the data distribution is managed by the operating system and the user provides annotations to indicate parallel control regions. In the case of C++, we look at pC++ which is based on a concurrent aggregate parallel model.

  5. “Working to shape what society's expectations of us should be”: Philip Morris' societal alignment strategy

    PubMed Central

    Yang, J S; Malone, R E

    2009-01-01

    Background A key element of Philip Morris's (PM's) corporate social responsibility initiatives is “societal alignment”, defined as “strategies and programs to meet society's expectations of a responsible tobacco company”. This study explored the genesis and implementation of Philip Morris' (PM) societal alignment efforts. Methods The study retrieved and analysed approximately 375 previously undisclosed PM documents now available electronically. Using an iterative process, the study categorised themes and prepared a case analysis. Results Beginning in 1999, PM sought to become “societally aligned” by identifying expectations of a responsible tobacco company through public opinion research and developing and publicising programs to meet those expectations. Societal alignment was undertaken within the US and globally to ensure an environment favourable to PM's business objectives. Despite PM's claims to be “changing”, however, societal alignment in practice was highly selective. PM responded to public “expectations” largely by retooling existing positions and programs, while entirely ignoring other expectations that might have interfered with its business goals. It also appears that convincing employees of the value and authenticity of societal alignment was difficult. Conclusions As implementation of the Framework Convention on Tobacco Control proceeds, tobacco control advocates should closely monitor development of such “alignment” initiatives and expose the motivations and contradictions they reveal. PMID:18845623

  6. Aligning Career and Technical Education with High-Wage and High-Demand Occupations in Tennessee. Issues & Answers. REL 2011-No. 111

    ERIC Educational Resources Information Center

    Mokher, Christine

    2011-01-01

    This study examines the availability of career and technical education program areas in Tennessee high schools, concentrations (a three-or-more credit sequence in a program area) completed by 2007/08 high school graduates, and how these concentrations align with jobs in the labor market. It looks at how these outcomes differ, statewide and by…

  7. Alignments of Dark Matter Halos with Large-scale Tidal Fields: Mass and Redshift Dependence

    NASA Astrophysics Data System (ADS)

    Chen, Sijie; Wang, Huiyuan; Mo, H. J.; Shi, Jingjing

    2016-07-01

    Large-scale tidal fields estimated directly from the distribution of dark matter halos are used to investigate how halo shapes and spin vectors are aligned with the cosmic web. The major, intermediate, and minor axes of halos are aligned with the corresponding tidal axes, and halo spin axes tend to be parallel with the intermediate axes and perpendicular to the major axes of the tidal field. The strengths of these alignments generally increase with halo mass and redshift, but the dependence is only on the peak height, ν \\equiv {δ }{{c}}/σ ({M}{{h}},z). The scaling relations of the alignment strengths with the value of ν indicate that the alignment strengths remain roughly constant when the structures within which the halos reside are still in a quasi-linear regime, but decreases as nonlinear evolution becomes more important. We also calculate the alignments in projection so that our results can be compared directly with observations. Finally, we investigate the alignments of tidal tensors on large scales, and use the results to understand alignments of halo pairs separated at various distances. Our results suggest that the coherent structure of the tidal field is the underlying reason for the alignments of halos and galaxies seen in numerical simulations and in observations.

  8. Quantum size and electric field modulations on electronic structures of SnS2/BN hetero-multilayers

    NASA Astrophysics Data System (ADS)

    Xia, Congxin; Zhang, Qian; Xiao, Wenbo; Du, Juan; Li, Xueping; Li, Jingbo

    2018-05-01

    Through first-principles calculations, we study the stability, band structures, band alignment, and interlayer charge transfer of SnS2/BN hetero-multilayers, considering quantum size and electric field effects. We find that SnS2/BN hetero-multilayers possess the characteristics of direct band structures and type-II band alignment. Moreover, increasing the BN layer number can decrease the band gap value and work function. Additionally, type-II can be tuned to type-I band alignment in the presence of an electric field. These results indicate that the SnS2/BN system is different from that of other BN-based hybrid materials, such as MoS2/BN with type-I band alignment, which is promising for optoelectronic device applications.

  9. Active alignment/contact verification system

    DOEpatents

    Greenbaum, William M.

    2000-01-01

    A system involving an active (i.e. electrical) technique for the verification of: 1) close tolerance mechanical alignment between two component, and 2) electrical contact between mating through an elastomeric interface. For example, the two components may be an alumina carrier and a printed circuit board, two mating parts that are extremely small, high density parts and require alignment within a fraction of a mil, as well as a specified interface point of engagement between the parts. The system comprises pairs of conductive structures defined in the surfaces layers of the alumina carrier and the printed circuit board, for example. The first pair of conductive structures relate to item (1) above and permit alignment verification between mating parts. The second pair of conductive structures relate to item (2) above and permit verification of electrical contact between mating parts.

  10. PFAAT version 2.0: a tool for editing, annotating, and analyzing multiple sequence alignments.

    PubMed

    Caffrey, Daniel R; Dana, Paul H; Mathur, Vidhya; Ocano, Marco; Hong, Eun-Jong; Wang, Yaoyu E; Somaroo, Shyamal; Caffrey, Brian E; Potluri, Shobha; Huang, Enoch S

    2007-10-11

    By virtue of their shared ancestry, homologous sequences are similar in their structure and function. Consequently, multiple sequence alignments are routinely used to identify trends that relate to function. This type of analysis is particularly productive when it is combined with structural and phylogenetic analysis. Here we describe the release of PFAAT version 2.0, a tool for editing, analyzing, and annotating multiple sequence alignments. Support for multiple annotations is a key component of this release as it provides a framework for most of the new functionalities. The sequence annotations are accessible from the alignment and tree, where they are typically used to label sequences or hyperlink them to related databases. Sequence annotations can be created manually or extracted automatically from UniProt entries. Once a multiple sequence alignment is populated with sequence annotations, sequences can be easily selected and sorted through a sophisticated search dialog. The selected sequences can be further analyzed using statistical methods that explicitly model relationships between the sequence annotations and residue properties. Residue annotations are accessible from the alignment viewer and are typically used to designate binding sites or properties for a particular residue. Residue annotations are also searchable, and allow one to quickly select alignment columns for further sequence analysis, e.g. computing percent identities. Other features include: novel algorithms to compute sequence conservation, mapping conservation scores to a 3D structure in Jmol, displaying secondary structure elements, and sorting sequences by residue composition. PFAAT provides a framework whereby end-users can specify knowledge for a protein family in the form of annotation. The annotations can be combined with sophisticated analysis to test hypothesis that relate to sequence, structure and function.

  11. High-speed multiple sequence alignment on a reconfigurable platform.

    PubMed

    Oliver, Tim; Schmidt, Bertil; Maskell, Douglas; Nathan, Darran; Clemens, Ralf

    2006-01-01

    Progressive alignment is a widely used approach to compute multiple sequence alignments (MSAs). However, aligning several hundred sequences by popular progressive alignment tools requires hours on sequential computers. Due to the rapid growth of sequence databases biologists have to compute MSAs in a far shorter time. In this paper we present a new approach to MSA on reconfigurable hardware platforms to gain high performance at low cost. We have constructed a linear systolic array to perform pairwise sequence distance computations using dynamic programming. This results in an implementation with significant runtime savings on a standard FPGA.

  12. Finding Protein and Nucleotide Similarities with FASTA

    PubMed Central

    Pearson, William R.

    2016-01-01

    The FASTA programs provide a comprehensive set of rapid similarity searching tools ( fasta36, fastx36, tfastx36, fasty36, tfasty36), similar to those provided by the BLAST package, as well as programs for slower, optimal, local and global similarity searches ( ssearch36, ggsearch36) and for searching with short peptides and oligonucleotides ( fasts36, fastm36). The FASTA programs use an empirical strategy for estimating statistical significance that accommodates a range of similarity scoring matrices and gap penalties, improving alignment boundary accuracy and search sensitivity (Unit 3.5). The FASTA programs can produce “BLAST-like” alignment and tabular output, for ease of integration into existing analysis pipelines, and can search small, representative databases, and then report results for a larger set of sequences, using links from the smaller dataset. The FASTA programs work with a wide variety of database formats, including mySQL and postgreSQL databases (Unit 9.4). The programs also provide a strategy for integrating domain and active site annotations into alignments and highlighting the mutational state of functionally critical residues. These protocols describe how to use the FASTA programs to characterize protein and DNA sequences, using protein:protein, protein:DNA, and DNA:DNA comparisons. PMID:27010337

  13. Finding Protein and Nucleotide Similarities with FASTA.

    PubMed

    Pearson, William R

    2016-03-24

    The FASTA programs provide a comprehensive set of rapid similarity searching tools (fasta36, fastx36, tfastx36, fasty36, tfasty36), similar to those provided by the BLAST package, as well as programs for slower, optimal, local, and global similarity searches (ssearch36, ggsearch36), and for searching with short peptides and oligonucleotides (fasts36, fastm36). The FASTA programs use an empirical strategy for estimating statistical significance that accommodates a range of similarity scoring matrices and gap penalties, improving alignment boundary accuracy and search sensitivity. The FASTA programs can produce "BLAST-like" alignment and tabular output, for ease of integration into existing analysis pipelines, and can search small, representative databases, and then report results for a larger set of sequences, using links from the smaller dataset. The FASTA programs work with a wide variety of database formats, including mySQL and postgreSQL databases. The programs also provide a strategy for integrating domain and active site annotations into alignments and highlighting the mutational state of functionally critical residues. These protocols describe how to use the FASTA programs to characterize protein and DNA sequences, using protein:protein, protein:DNA, and DNA:DNA comparisons. Copyright © 2016 John Wiley & Sons, Inc.

  14. AssignFit: a program for simultaneous assignment and structure refinement from solid-state NMR spectra

    PubMed Central

    Tian, Ye; Schwieters, Charles D.; Opella, Stanley J.; Marassi, Francesca M.

    2011-01-01

    AssignFit is a computer program developed within the XPLOR-NIH package for the assignment of dipolar coupling (DC) and chemical shift anisotropy (CSA) restraints derived from the solid-state NMR spectra of protein samples with uniaxial order. The method is based on minimizing the difference between experimentally observed solid-state NMR spectra and the frequencies back calculated from a structural model. Starting with a structural model and a set of DC and CSA restraints grouped only by amino acid type, as would be obtained by selective isotopic labeling, AssignFit generates all of the possible assignment permutations and calculates the corresponding atomic coordinates oriented in the alignment frame, together with the associated set of NMR frequencies, which are then compared with the experimental data for best fit. Incorporation of AssignFit in a simulated annealing refinement cycle provides an approach for simultaneous assignment and structure refinement (SASR) of proteins from solid-state NMR orientation restraints. The methods are demonstrated with data from two integral membrane proteins, one α-helical and one β-barrel, embedded in phospholipid bilayer membranes. PMID:22036904

  15. Representation of molecular structure using quantum topology with inductive logic programming in structure-activity relationships.

    PubMed

    Buttingsrud, Bård; Ryeng, Einar; King, Ross D; Alsberg, Bjørn K

    2006-06-01

    The requirement of aligning each individual molecule in a data set severely limits the type of molecules which can be analysed with traditional structure activity relationship (SAR) methods. A method which solves this problem by using relations between objects is inductive logic programming (ILP). Another advantage of this methodology is its ability to include background knowledge as 1st-order logic. However, previous molecular ILP representations have not been effective in describing the electronic structure of molecules. We present a more unified and comprehensive representation based on Richard Bader's quantum topological atoms in molecules (AIM) theory where critical points in the electron density are connected through a network. AIM theory provides a wealth of chemical information about individual atoms and their bond connections enabling a more flexible and chemically relevant representation. To obtain even more relevant rules with higher coverage, we apply manual postprocessing and interpretation of ILP rules. We have tested the usefulness of the new representation in SAR modelling on classifying compounds of low/high mutagenicity and on a set of factor Xa inhibitors of high and low affinity.

  16. SANSparallel: interactive homology search against Uniprot.

    PubMed

    Somervuo, Panu; Holm, Liisa

    2015-07-01

    Proteins evolve by mutations and natural selection. The network of sequence similarities is a rich source for mining homologous relationships that inform on protein structure and function. There are many servers available to browse the network of homology relationships but one has to wait up to a minute for results. The SANSparallel webserver provides protein sequence database searches with immediate response and professional alignment visualization by third-party software. The output is a list, pairwise alignment or stacked alignment of sequence-similar proteins from Uniprot, UniRef90/50, Swissprot or Protein Data Bank. The stacked alignments are viewed in Jalview or as sequence logos. The database search uses the suffix array neighborhood search (SANS) method, which has been re-implemented as a client-server, improved and parallelized. The method is extremely fast and as sensitive as BLAST above 50% sequence identity. Benchmarks show that the method is highly competitive compared to previously published fast database search programs: UBLAST, DIAMOND, LAST, LAMBDA, RAPSEARCH2 and BLAT. The web server can be accessed interactively or programmatically at http://ekhidna2.biocenter.helsinki.fi/cgi-bin/sans/sans.cgi. It can be used to make protein functional annotation pipelines more efficient, and it is useful in interactive exploration of the detailed evidence supporting the annotation of particular proteins of interest. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Pteros: fast and easy to use open-source C++ library for molecular analysis.

    PubMed

    Yesylevskyy, Semen O

    2012-07-15

    An open-source Pteros library for molecular modeling and analysis of molecular dynamics trajectories for C++ programming language is introduced. Pteros provides a number of routine analysis operations ranging from reading and writing trajectory files and geometry transformations to structural alignment and computation of nonbonded interaction energies. The library features asynchronous trajectory reading and parallel execution of several analysis routines, which greatly simplifies development of computationally intensive trajectory analysis algorithms. Pteros programming interface is very simple and intuitive while the source code is well documented and easily extendible. Pteros is available for free under open-source Artistic License from http://sourceforge.net/projects/pteros/. Copyright © 2012 Wiley Periodicals, Inc.

  18. Square cell packing in the Drosophila embryo through spatiotemporally regulated EGF receptor signaling

    PubMed Central

    Tamada, Masako; Zallen, Jennifer A.

    2015-01-01

    Summary Cells display dynamic and diverse morphologies during development, but the strategies by which differentiated tissues achieve precise shapes and patterns are not well understood. Here we identify a developmental program that generates a highly ordered square cell grid in the Drosophila embryo through sequential and spatially regulated cell alignment, oriented cell division, and apicobasal cell elongation. The basic leucine zipper transcriptional regulator Cnc is necessary and sufficient to produce a square cell grid in the presence of a midline signal provided by the EGF receptor ligand, Spitz. Spitz orients cell divisions through a Pins/LGN-dependent spindle positioning mechanism and controls cell shape and alignment through a transcriptional pathway that requires the Pointed ETS domain protein. These results identify a strategy for producing ordered square cell packing configurations in epithelia and reveal a molecular mechanism by which organized tissue structure is generated through spatiotemporally regulated responses to EGF receptor activation. PMID:26506305

  19. Acoustic, Flow Related, and Performance Related Experimental Results for Generation 1.5 High Speed Civil Transport (HSCT) 2-Dimensional Exhaust Nozzles

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.; Wisler, S.; Majjigi, R.

    2004-01-01

    The principle objectives of the current program were to experimentally investigate the repeatability of acoustic and aerodynamic characteristics of 2D-CD mixer-ejector nozzles and the effects on the acoustic and aerodynamic characteristics of 2D mixer-ejectors due to (1) the configurational variations, which include mixers with aligned CD chutes, aligned convergent chutes, and staggered CD chutes and aerodynamic cycle variables, (2) treatment variations by using different treatment materials, treating the ejector with varying area, location, and treatment thickness for a mixer-ejector configuration, and (3) secondary inlet shape (i.e., a more realistic inlet) and the blockage across the inlet (a possible fin-like structure needed for installation purpose) by modifying one of the inlet of a mixer-ejector configuration. The objectives also included the measurement dynamic pressures internal to the ejector for a few selected configuration to examine the internal noise characteristics.

  20. Creating Next Generation Teacher Preparation Programs to Support Implementation of the Next Generation Science Standards and Common Core State Standards in K-12 Schools: An Opportunity for the Earth and Space Sciences

    NASA Astrophysics Data System (ADS)

    Geary, E. E.; Egger, A. E.; Julin, S.; Ronca, R.; Vokos, S.; Ebert, E.; Clark-Blickenstaff, J.; Nollmeyer, G.

    2015-12-01

    A consortium of two and four year Washington State Colleges and Universities in partnership with Washington's Office of the Superintendent of Public Instruction (OSPI), the Teachers of Teachers of Science, and Teachers of Teachers of Mathematics, and other key stakeholders, is currently working to improve science and mathematics learning for all Washington State students by creating a new vision for STEM teacher preparation in Washington State aligned with the Next Generation Science Standards (NGSS) and the Common Core State Standards (CCSS) in Mathematics and Language Arts. Specific objectives include: (1) strengthening elementary and secondary STEM Teacher Preparation courses and curricula, (2) alignment of STEM teacher preparation programs across Washington State with the NGSS and CCSS, (3) development of action plans to support implementation of STEM Teacher Preparation program improvement at Higher Education Institutions (HEIs) across the state, (4) stronger collaborations between HEIs, K-12 schools, government agencies, Non-Governmental Organizations, and STEM businesses, involved in the preparation of preservice STEM teachers, (5) new teacher endorsements in Computer Science and Engineering, and (6) development of a proto-type model for rapid, adaptable, and continuous improvement of STEM teacher preparation programs. A 2015 NGSS gap analysis of teacher preparation programs across Washington State indicates relatively good alignment of courses and curricula with NGSS Disciplinary Core Ideas and Scientific practices, but minimal alignment with NGSS Engineering practices and Cross Cutting Concepts. Likewise, Computer Science and Sustainability ideas and practices are not well represented in current courses and curricula. During the coming year teams of STEM faculty, education faculty and administrators will work collaboratively to develop unique action plans for aligning and improving STEM teacher preparation courses and curricula at their institutions.

  1. DNA Nanotubes for NMR Structure Determination of Membrane Proteins

    PubMed Central

    Bellot, Gaëtan; McClintock, Mark A.; Chou, James J; Shih, William M.

    2013-01-01

    Structure determination of integral membrane proteins by solution NMR represents one of the most important challenges of structural biology. A Residual-Dipolar-Coupling-based refinement approach can be used to solve the structure of membrane proteins up to 40 kDa in size, however, a weak-alignment medium that is detergent-resistant is required. Previously, availability of media suitable for weak alignment of membrane proteins was severely limited. We describe here a protocol for robust, large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into dilute liquid crystals for application as weak-alignment media in solution NMR structure determination of membrane proteins in detergent micelles. The DNA nanotubes are heterodimers of 400nm-long six-helix bundles each self-assembled from a M13-based p7308 scaffold strand and >170 short oligonucleotide staple strands. Compatibility with proteins bearing considerable positive charge as well as modulation of molecular alignment, towards collection of linearly independent restraints, can be introduced by reducing the negative charge of DNA nanotubes via counter ions and small DNA binding molecules. This detergent-resistant liquid-crystal media offers a number of properties conducive for membrane protein alignment, including high-yield production, thermal stability, buffer compatibility, and structural programmability. Production of sufficient nanotubes for 4–5 NMR experiments can be completed in one week by a single individual. PMID:23518667

  2. Local-global alignment for finding 3D similarities in protein structures

    DOEpatents

    Zemla, Adam T [Brentwood, CA

    2011-09-20

    A method of finding 3D similarities in protein structures of a first molecule and a second molecule. The method comprises providing preselected information regarding the first molecule and the second molecule. Comparing the first molecule and the second molecule using Longest Continuous Segments (LCS) analysis. Comparing the first molecule and the second molecule using Global Distance Test (GDT) analysis. Comparing the first molecule and the second molecule using Local Global Alignment Scoring function (LGA_S) analysis. Verifying constructed alignment and repeating the steps to find the regions of 3D similarities in protein structures.

  3. Fast online and index-based algorithms for approximate search of RNA sequence-structure patterns

    PubMed Central

    2013-01-01

    Background It is well known that the search for homologous RNAs is more effective if both sequence and structure information is incorporated into the search. However, current tools for searching with RNA sequence-structure patterns cannot fully handle mutations occurring on both these levels or are simply not fast enough for searching large sequence databases because of the high computational costs of the underlying sequence-structure alignment problem. Results We present new fast index-based and online algorithms for approximate matching of RNA sequence-structure patterns supporting a full set of edit operations on single bases and base pairs. Our methods efficiently compute semi-global alignments of structural RNA patterns and substrings of the target sequence whose costs satisfy a user-defined sequence-structure edit distance threshold. For this purpose, we introduce a new computing scheme to optimally reuse the entries of the required dynamic programming matrices for all substrings and combine it with a technique for avoiding the alignment computation of non-matching substrings. Our new index-based methods exploit suffix arrays preprocessed from the target database and achieve running times that are sublinear in the size of the searched sequences. To support the description of RNA molecules that fold into complex secondary structures with multiple ordered sequence-structure patterns, we use fast algorithms for the local or global chaining of approximate sequence-structure pattern matches. The chaining step removes spurious matches from the set of intermediate results, in particular of patterns with little specificity. In benchmark experiments on the Rfam database, our improved online algorithm is faster than the best previous method by up to factor 45. Our best new index-based algorithm achieves a speedup of factor 560. Conclusions The presented methods achieve considerable speedups compared to the best previous method. This, together with the expected sublinear running time of the presented index-based algorithms, allows for the first time approximate matching of RNA sequence-structure patterns in large sequence databases. Beyond the algorithmic contributions, we provide with RaligNAtor a robust and well documented open-source software package implementing the algorithms presented in this manuscript. The RaligNAtor software is available at http://www.zbh.uni-hamburg.de/ralignator. PMID:23865810

  4. Bioinformatics prediction of siRNAs as potential antiviral agents against dengue viruses

    PubMed Central

    Villegas-Rosales, Paula M; Méndez-Tenorio, Alfonso; Ortega-Soto, Elizabeth; Barrón, Blanca L

    2012-01-01

    Dengue virus (DENV 1-4) represents the major emerging arthropod-borne viral infection in the world. Currently, there is neither an available vaccine nor a specific treatment. Hence, there is a need of antiviral drugs for these viral infections; we describe the prediction of short interfering RNA (siRNA) as potential therapeutic agents against the four DENV serotypes. Our strategy was to carry out a series of multiple alignments using ClustalX program to find conserved sequences among the four DENV serotype genomes to obtain a consensus sequence for siRNAs design. A highly conserved sequence among the four DENV serotypes, located in the encoding sequence for NS4B and NS5 proteins was found. A total of 2,893 complete DENV genomes were downloaded from the NCBI, and after a depuration procedure to identify identical sequences, 220 complete DENV genomes were left. They were edited to select the NS4B and NS5 sequences, which were aligned to obtain a consensus sequence. Three different servers were used for siRNA design, and the resulting siRNAs were aligned to identify the most prevalent sequences. Three siRNAs were chosen, one targeted the genome region that codifies for NS4B protein and the other two; the region for NS5 protein. Predicted secondary structure for DENV genomes was used to demonstrate that the siRNAs were able to target the viral genome forming double stranded structures, necessary to activate the RNA silencing machinery. PMID:22829722

  5. Aligning Career and Technical Education with High-Wage and High-Demand Occupations in Tennessee. Summary. Issues & Answers. REL 2011-No. 111

    ERIC Educational Resources Information Center

    Mokher, Christine

    2011-01-01

    This study examines the availability of career and technical education program areas in Tennessee high schools, concentrations (a three-or-more credit sequence in a program area) completed by 2007/08 high school graduates, and how these concentrations align with jobs in the labor market. It looks at how these outcomes differ, statewide and by…

  6. Bellerophon: a program to detect chimeric sequences in multiple sequence alignments.

    PubMed

    Huber, Thomas; Faulkner, Geoffrey; Hugenholtz, Philip

    2004-09-22

    Bellerophon is a program for detecting chimeric sequences in multiple sequence datasets by an adaption of partial treeing analysis. Bellerophon was specifically developed to detect 16S rRNA gene chimeras in PCR-clone libraries of environmental samples but can be applied to other nucleotide sequence alignments. Bellerophon is available as an interactive web server at http://foo.maths.uq.edu.au/~huber/bellerophon.pl

  7. Aligning library instruction with the needs of basic sciences graduate students: a case study.

    PubMed

    O'Malley, Donna; Delwiche, Frances A

    2012-10-01

    How can an existing library instruction program be reconfigured to reach basic sciences graduate students and other patrons missed by curriculum-based instruction? The setting is an academic health sciences library that serves both the university and its affiliated teaching hospital. The existing program was redesigned to incorporate a series of seven workshops that encompassed the range of information literacy skills that graduate students in the basic sciences need. In developing the new model, the teaching librarians made changes in pedagogy, technology, marketing, and assessment strategies. Total attendance at the sessions increased substantially in the first 2 years of the new model, increasing from an average of 20 per semester to an average of 124. Survey results provided insight about what patrons wanted to learn and how best to teach it. Modifying the program's content and structure resulted in a program that appealed to the target audience.

  8. Formation of the Sun-aligned arc region and the void (polar slot) under the null-separator structure

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Obara, T.; Watanabe, M.; Fujita, S.; Ebihara, Y.; Kataoka, R.

    2017-04-01

    From the global magnetosphere-ionosphere coupling simulation, we examined the formation of the Sun-aligned arc region and the void (polar slot) under the northward interplanetary magnetic field (IMF) with negative By condition. In the magnetospheric null-separator structure, the separatrices generated from two null points and two separators divide the entire space into four types of magnetic region, i.e., the IMF, the northern open magnetic field, the southern open magnetic field, and the closed magnetic field. In the ionosphere, the Sun-aligned arc region and the void are reproduced in the distributions of simulated plasma pressure and field-aligned current. The outermost closed magnetic field lines on the boundary (separatrix) between the northern open magnetic field and the closed magnetic field are projected to the northern ionosphere at the boundary between the Sun-aligned arc region and the void, both on the morning and evening sides. The magnetic field lines at the plasma sheet inner edge are projected to the equatorward boundary of the oval. Therefore, the Sun-aligned arc region is on the closed magnetic field lines of the plasma sheet. In the plasma sheet, an inflated structure (bulge) is generated at the junction of the tilted plasma sheet in the far-to-middle tail and nontilted plasma sheet in the ring current region. In the Northern Hemisphere, the bulge is on the evening side wrapped by the outermost closed magnetic field lines that are connected to the northern evening ionosphere. This inflated structure (bulge) is associated with shear flows that cause the Sun-aligned arc.

  9. A scalable architecture for extracting, aligning, linking, and visualizing multi-Int data

    NASA Astrophysics Data System (ADS)

    Knoblock, Craig A.; Szekely, Pedro

    2015-05-01

    An analyst today has a tremendous amount of data available, but each of the various data sources typically exists in their own silos, so an analyst has limited ability to see an integrated view of the data and has little or no access to contextual information that could help in understanding the data. We have developed the Domain-Insight Graph (DIG) system, an innovative architecture for extracting, aligning, linking, and visualizing massive amounts of domain-specific content from unstructured sources. Under the DARPA Memex program we have already successfully applied this architecture to multiple application domains, including the enormous international problem of human trafficking, where we extracted, aligned and linked data from 50 million online Web pages. DIG builds on our Karma data integration toolkit, which makes it easy to rapidly integrate structured data from a variety of sources, including databases, spreadsheets, XML, JSON, and Web services. The ability to integrate Web services allows Karma to pull in live data from the various social media sites, such as Twitter, Instagram, and OpenStreetMaps. DIG then indexes the integrated data and provides an easy to use interface for query, visualization, and analysis.

  10. Self-aligning and compressed autosophy video databases

    NASA Astrophysics Data System (ADS)

    Holtz, Klaus E.

    1993-04-01

    Autosophy, an emerging new science, explains `self-assembling structures,' such as crystals or living trees, in mathematical terms. This research provides a new mathematical theory of `learning' and a new `information theory' which permits the growing of self-assembling data network in a computer memory similar to the growing of `data crystals' or `data trees' without data processing or programming. Autosophy databases are educated very much like a human child to organize their own internal data storage. Input patterns, such as written questions or images, are converted to points in a mathematical omni dimensional hyperspace. The input patterns are then associated with output patterns, such as written answers or images. Omni dimensional information storage will result in enormous data compression because each pattern fragment is only stored once. Pattern recognition in the text or image files is greatly simplified by the peculiar omni dimensional storage method. Video databases will absorb input images from a TV camera and associate them with textual information. The `black box' operations are totally self-aligning where the input data will determine their own hyperspace storage locations. Self-aligning autosophy databases may lead to a new generation of brain-like devices.

  11. High-harmonic spectroscopy of aligned molecules

    NASA Astrophysics Data System (ADS)

    Yun, Hyeok; Yun, Sang Jae; Lee, Gae Hwang; Nam, Chang Hee

    2017-01-01

    High harmonics emitted from aligned molecules driven by intense femtosecond laser pulses provide the opportunity to explore the structural information of molecules. The field-free molecular alignment technique is an expedient tool for investigating the structural characteristics of linear molecules. The underlying physics of field-free alignment, showing the characteristic revival structure specific to molecular species, is clearly explained from the quantum-phase analysis of molecular rotational states. The anisotropic nature of molecules is shown from the harmonic polarization measurement performed with spatial interferometry. The multi-orbital characteristics of molecules are investigated using high-harmonic spectroscopy, applied to molecules of N2 and CO2. In the latter case the two-dimensional high-harmonic spectroscopy, implemented using a two-color laser field, is applied to distinguish harmonics from different orbitals. Molecular high-harmonic spectroscopy will open a new route to investigate ultrafast dynamics of molecules.

  12. GATA: A graphic alignment tool for comparative sequenceanalysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nix, David A.; Eisen, Michael B.

    2005-01-01

    Several problems exist with current methods used to align DNA sequences for comparative sequence analysis. Most dynamic programming algorithms assume that conserved sequence elements are collinear. This assumption appears valid when comparing orthologous protein coding sequences. Functional constraints on proteins provide strong selective pressure against sequence inversions, and minimize sequence duplications and feature shuffling. For non-coding sequences this collinearity assumption is often invalid. For example, enhancers contain clusters of transcription factor binding sites that change in number, orientation, and spacing during evolution yet the enhancer retains its activity. Dotplot analysis is often used to estimate non-coding sequence relatedness. Yet dotmore » plots do not actually align sequences and thus cannot account well for base insertions or deletions. Moreover, they lack an adequate statistical framework for comparing sequence relatedness and are limited to pairwise comparisons. Lastly, dot plots and dynamic programming text outputs fail to provide an intuitive means for visualizing DNA alignments.« less

  13. Method for alignment of microwires

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beardslee, Joseph A.; Lewis, Nathan S.; Sadtler, Bryce

    2017-01-24

    A method of aligning microwires includes modifying the microwires so they are more responsive to a magnetic field. The method also includes using a magnetic field so as to magnetically align the microwires. The method can further include capturing the microwires in a solid support structure that retains the longitudinal alignment of the microwires when the magnetic field is not applied to the microwires.

  14. Development of Software to Model AXAF-I Image Quality

    NASA Technical Reports Server (NTRS)

    Ahmad, Anees; Hawkins, Lamar

    1996-01-01

    This draft final report describes the work performed under the delivery order number 145 from May 1995 through August 1996. The scope of work included a number of software development tasks for the performance modeling of AXAF-I. A number of new capabilities and functions have been added to the GT software, which is the command mode version of the GRAZTRACE software, originally developed by MSFC. A structural data interface has been developed for the EAL (old SPAR) finite element analysis FEA program, which is being used by MSFC Structural Analysis group for the analysis of AXAF-I. This interface utility can read the structural deformation file from the EAL and other finite element analysis programs such as NASTRAN and COSMOS/M, and convert the data to a suitable format that can be used for the deformation ray-tracing to predict the image quality for a distorted mirror. There is a provision in this utility to expand the data from finite element models assuming 180 degrees symmetry. This utility has been used to predict image characteristics for the AXAF-I HRMA, when subjected to gravity effects in the horizontal x-ray ground test configuration. The development of the metrology data processing interface software has also been completed. It can read the HDOS FITS format surface map files, manipulate and filter the metrology data, and produce a deformation file, which can be used by GT for ray tracing for the mirror surface figure errors. This utility has been used to determine the optimum alignment (axial spacing and clocking) for the four pairs of AXAF-I mirrors. Based on this optimized alignment, the geometric images and effective focal lengths for the as built mirrors were predicted to cross check the results obtained by Kodak.

  15. AGILE: Autonomous Global Integrated Language Exploitation

    DTIC Science & Technology

    2009-12-01

    combination, including METEOR-based alignment (with stemming and WordNet synonym matching) and GIZA ++ based alignment. So far, we have not seen any...parse trees and a detailed analysis of how function words operate in translation. This program lets us fix alignment errors that systems like GIZA ...correlates better with Pyramid than with Responsiveness scoring (i.e., it is a more precise, careful, measure) • BE generally outperforms ROUGE

  16. Dimension towers of SICs. I. Aligned SICs and embedded tight frames

    NASA Astrophysics Data System (ADS)

    Appleby, Marcus; Bengtsson, Ingemar; Dumitru, Irina; Flammia, Steven

    2017-11-01

    Algebraic number theory relates SIC-POVMs in dimension d > 3 to those in dimension d(d - 2). We define a SIC in dimension d(d - 2) to be aligned to a SIC in dimension d if and only if the squares of the overlap phases in dimension d appear as a subset of the overlap phases in dimension d(d - 2) in a specified way. We give 19 (mostly numerical) examples of aligned SICs. We conjecture that given any SIC in dimension d, there exists an aligned SIC in dimension d(d - 2). In all our examples, the aligned SIC has lower dimensional equiangular tight frames embedded in it. If d is odd so that a natural tensor product structure exists, we prove that the individual vectors in the aligned SIC have a very special entanglement structure, and the existence of the embedded tight frames follows as a theorem. If d - 2 is an odd prime number, we prove that a complete set of mutually unbiased bases can be obtained by reducing an aligned SIC to this dimension.

  17. Physically motivated global alignment method for electron tomography

    DOE PAGES

    Sanders, Toby; Prange, Micah; Akatay, Cem; ...

    2015-04-08

    Electron tomography is widely used for nanoscale determination of 3-D structures in many areas of science. Determining the 3-D structure of a sample from electron tomography involves three major steps: acquisition of sequence of 2-D projection images of the sample with the electron microscope, alignment of the images to a common coordinate system, and 3-D reconstruction and segmentation of the sample from the aligned image data. The resolution of the 3-D reconstruction is directly influenced by the accuracy of the alignment, and therefore, it is crucial to have a robust and dependable alignment method. In this paper, we develop amore » new alignment method which avoids the use of markers and instead traces the computed paths of many identifiable ‘local’ center-of-mass points as the sample is rotated. Compared with traditional correlation schemes, the alignment method presented here is resistant to cumulative error observed from correlation techniques, has very rigorous mathematical justification, and is very robust since many points and paths are used, all of which inevitably improves the quality of the reconstruction and confidence in the scientific results.« less

  18. Technology Alignment and Portfolio Prioritization (TAPP)

    NASA Technical Reports Server (NTRS)

    Funaro, Gregory V.; Alexander, Reginald A.

    2015-01-01

    Technology Alignment and Portfolio Prioritization (TAPP) is a method being developed by the Advanced Concepts Office, at NASA Marshall Space Flight Center. The TAPP method expands on current technology assessment methods by incorporating the technological structure underlying technology development, e.g., organizational structures and resources, institutional policy and strategy, and the factors that motivate technological change. This paper discusses the methods ACO is currently developing to better perform technology assessments while taking into consideration Strategic Alignment, Technology Forecasting, and Long Term Planning.

  19. fRMSDPred: Predicting Local RMSD Between Structural Fragments Using Sequence Information

    DTIC Science & Technology

    2007-04-04

    machine learning approaches for estimating the RMSD value of a pair of protein fragments. These estimated fragment-level RMSD values can be used to construct the alignment, assess the quality of an alignment, and identify high-quality alignment segments. We present algorithms to solve this fragment-level RMSD prediction problem using a supervised learning framework based on support vector regression and classification that incorporates protein profiles, predicted secondary structure, effective information encoding schemes, and novel second-order pairwise exponential kernel

  20. LenVarDB: database of length-variant protein domains.

    PubMed

    Mutt, Eshita; Mathew, Oommen K; Sowdhamini, Ramanathan

    2014-01-01

    Protein domains are functionally and structurally independent modules, which add to the functional variety of proteins. This array of functional diversity has been enabled by evolutionary changes, such as amino acid substitutions or insertions or deletions, occurring in these protein domains. Length variations (indels) can introduce changes at structural, functional and interaction levels. LenVarDB (freely available at http://caps.ncbs.res.in/lenvardb/) traces these length variations, starting from structure-based sequence alignments in our Protein Alignments organized as Structural Superfamilies (PASS2) database, across 731 structural classification of proteins (SCOP)-based protein domain superfamilies connected to 2 730 625 sequence homologues. Alignment of sequence homologues corresponding to a structural domain is available, starting from a structure-based sequence alignment of the superfamily. Orientation of the length-variant (indel) regions in protein domains can be visualized by mapping them on the structure and on the alignment. Knowledge about location of length variations within protein domains and their visual representation will be useful in predicting changes within structurally or functionally relevant sites, which may ultimately regulate protein function. Non-technical summary: Evolutionary changes bring about natural changes to proteins that may be found in many organisms. Such changes could be reflected as amino acid substitutions or insertions-deletions (indels) in protein sequences. LenVarDB is a database that provides an early overview of observed length variations that were set among 731 protein families and after examining >2 million sequences. Indels are followed up to observe if they are close to the active site such that they can affect the activity of proteins. Inclusion of such information can aid the design of bioengineering experiments.

  1. An alternative view of protein fold space.

    PubMed

    Shindyalov, I N; Bourne, P E

    2000-02-15

    Comparing and subsequently classifying protein structures information has received significant attention concurrent with the increase in the number of experimentally derived 3-dimensional structures. Classification schemes have focused on biological function found within protein domains and on structure classification based on topology. Here an alternative view is presented that groups substructures. Substructures are long (50-150 residue) highly repetitive near-contiguous pieces of polypeptide chain that occur frequently in a set of proteins from the PDB defined as structurally non-redundant over the complete polypeptide chain. The substructure classification is based on a previously reported Combinatorial Extension (CE) algorithm that provides a significantly different set of structure alignments than those previously described, having, for example, only a 40% overlap with FSSP. Qualitatively the algorithm provides longer contiguous aligned segments at the price of a slightly higher root-mean-square deviation (rmsd). Clustering these alignments gives a discreet and highly repetitive set of substructures not detectable by sequence similarity alone. In some cases different substructures represent all or different parts of well known folds indicative of the Russian doll effect--the continuity of protein fold space. In other cases they fall into different structure and functional classifications. It is too early to determine whether these newly classified substructures represent new insights into the evolution of a structural framework important to many proteins. What is apparent from on-going work is that these substructures have the potential to be useful probes in finding remote sequence homology and in structure prediction studies. The characteristics of the complete all-by-all comparison of the polypeptide chains present in the PDB and details of the filtering procedure by pair-wise structure alignment that led to the emergent substructure gallery are discussed. Substructure classification, alignments, and tools to analyze them are available at http://cl.sdsc.edu/ce.html.

  2. Summarizing Audiovisual Contents of a Video Program

    NASA Astrophysics Data System (ADS)

    Gong, Yihong

    2003-12-01

    In this paper, we focus on video programs that are intended to disseminate information and knowledge such as news, documentaries, seminars, etc, and present an audiovisual summarization system that summarizes the audio and visual contents of the given video separately, and then integrating the two summaries with a partial alignment. The audio summary is created by selecting spoken sentences that best present the main content of the audio speech while the visual summary is created by eliminating duplicates/redundancies and preserving visually rich contents in the image stream. The alignment operation aims to synchronize each spoken sentence in the audio summary with its corresponding speaker's face and to preserve the rich content in the visual summary. A Bipartite Graph-based audiovisual alignment algorithm is developed to efficiently find the best alignment solution that satisfies these alignment requirements. With the proposed system, we strive to produce a video summary that: (1) provides a natural visual and audio content overview, and (2) maximizes the coverage for both audio and visual contents of the original video without having to sacrifice either of them.

  3. G protein-coupled odorant receptors: From sequence to structure.

    PubMed

    de March, Claire A; Kim, Soo-Kyung; Antonczak, Serge; Goddard, William A; Golebiowski, Jérôme

    2015-09-01

    Odorant receptors (ORs) are the largest subfamily within class A G protein-coupled receptors (GPCRs). No experimental structural data of any OR is available to date and atomic-level insights are likely to be obtained by means of molecular modeling. In this article, we critically align sequences of ORs with those GPCRs for which a structure is available. Here, an alignment consistent with available site-directed mutagenesis data on various ORs is proposed. Using this alignment, the choice of the template is deemed rather minor for identifying residues that constitute the wall of the binding cavity or those involved in G protein recognition. © 2015 The Protein Society.

  4. Energy Level Alignment at the Interface between Linear-Structured Benzenediamine Molecules and Au(111) Surface

    NASA Astrophysics Data System (ADS)

    Li, Guo; Rangel, Tonatiuh; Liu, Zhenfei; Cooper, Valentino; Neaton, Jeffrey

    Using density functional theory with model self-energy corrections, we calculate the adsorption energetics and geometry, and the energy level alignment of benzenediamine (BDA) molecules adsorbed on Au(111) surfaces. Our calculations show that linear structures of BDA, stabilized via hydrogen bonds between amine groups, are energetically more favorable than monomeric phases. Moreover, our self-energy-corrected calculations of energy level alignment show that the highest occupied molecular orbital energy of the BDA linear structure is deeper relative to the Fermi level relative to the isolated monomer and agrees well with the values measured with photoemission spectroscopy. This work supported by DOE.

  5. G protein-coupled odorant receptors: From sequence to structure

    PubMed Central

    de March, Claire A; Kim, Soo-Kyung; Antonczak, Serge; Goddard, William A; Golebiowski, Jérôme

    2015-01-01

    Odorant receptors (ORs) are the largest subfamily within class A G protein-coupled receptors (GPCRs). No experimental structural data of any OR is available to date and atomic-level insights are likely to be obtained by means of molecular modeling. In this article, we critically align sequences of ORs with those GPCRs for which a structure is available. Here, an alignment consistent with available site-directed mutagenesis data on various ORs is proposed. Using this alignment, the choice of the template is deemed rather minor for identifying residues that constitute the wall of the binding cavity or those involved in G protein recognition. PMID:26044705

  6. StralSV: assessment of sequence variability within similar 3D structures and application to polio RNA-dependent RNA polymerase.

    PubMed

    Zemla, Adam T; Lang, Dorothy M; Kostova, Tanya; Andino, Raul; Ecale Zhou, Carol L

    2011-06-02

    Most of the currently used methods for protein function prediction rely on sequence-based comparisons between a query protein and those for which a functional annotation is provided. A serious limitation of sequence similarity-based approaches for identifying residue conservation among proteins is the low confidence in assigning residue-residue correspondences among proteins when the level of sequence identity between the compared proteins is poor. Multiple sequence alignment methods are more satisfactory--still, they cannot provide reliable results at low levels of sequence identity. Our goal in the current work was to develop an algorithm that could help overcome these difficulties by facilitating the identification of structurally (and possibly functionally) relevant residue-residue correspondences between compared protein structures. Here we present StralSV (structure-alignment sequence variability), a new algorithm for detecting closely related structure fragments and quantifying residue frequency from tight local structure alignments. We apply StralSV in a study of the RNA-dependent RNA polymerase of poliovirus, and we demonstrate that the algorithm can be used to determine regions of the protein that are relatively unique, or that share structural similarity with proteins that would be considered distantly related. By quantifying residue frequencies among many residue-residue pairs extracted from local structural alignments, one can infer potential structural or functional importance of specific residues that are determined to be highly conserved or that deviate from a consensus. We further demonstrate that considerable detailed structural and phylogenetic information can be derived from StralSV analyses. StralSV is a new structure-based algorithm for identifying and aligning structure fragments that have similarity to a reference protein. StralSV analysis can be used to quantify residue-residue correspondences and identify residues that may be of particular structural or functional importance, as well as unusual or unexpected residues at a given sequence position. StralSV is provided as a web service at http://proteinmodel.org/AS2TS/STRALSV/.

  7. Unsupervised image matching based on manifold alignment.

    PubMed

    Pei, Yuru; Huang, Fengchun; Shi, Fuhao; Zha, Hongbin

    2012-08-01

    This paper challenges the issue of automatic matching between two image sets with similar intrinsic structures and different appearances, especially when there is no prior correspondence. An unsupervised manifold alignment framework is proposed to establish correspondence between data sets by a mapping function in the mutual embedding space. We introduce a local similarity metric based on parameterized distance curves to represent the connection of one point with the rest of the manifold. A small set of valid feature pairs can be found without manual interactions by matching the distance curve of one manifold with the curve cluster of the other manifold. To avoid potential confusions in image matching, we propose an extended affine transformation to solve the nonrigid alignment in the embedding space. The comparatively tight alignments and the structure preservation can be obtained simultaneously. The point pairs with the minimum distance after alignment are viewed as the matchings. We apply manifold alignment to image set matching problems. The correspondence between image sets of different poses, illuminations, and identities can be established effectively by our approach.

  8. Rapid shear alignment of sub-10 nm cylinder-forming block copolymer films based on thermal expansion mismatch

    NASA Astrophysics Data System (ADS)

    Nicaise, Samuel M.; Gadelrab, Karim R.; G, Amir Tavakkoli K.; Ross, Caroline A.; Alexander-Katz, Alfredo; Berggren, Karl K.

    2018-01-01

    Directed self-assembly of block copolymers (BCPs) provided by shear-stress can produce aligned sub-10 nm structures over large areas for applications in integrated circuits, next-generation data storage, and plasmonic structures. In this work, we present a fast, versatile BCP shear-alignment process based on coefficient of thermal expansion mismatch of the BCP film, a rigid top coat and a substrate. Monolayer and bilayer cylindrical microdomains of poly(styrene-b-dimethylsiloxane) aligned preferentially in-plane and orthogonal to naturally-forming or engineered cracks in the top coat film, allowing for orientation control over 1 cm2 substrates. Annealing temperatures, up to 275 °C, provided low-defect alignment up to 2 mm away from cracks for rapid (<1 min) annealing times. Finite-element simulations of the stress as a function of annealing time, annealing temperature, and distance from cracks showed that shear stress during the cooling phase of the thermal annealing was critical for the observed microdomain alignment.

  9. Statistical Significance of Optical Map Alignments

    PubMed Central

    Sarkar, Deepayan; Goldstein, Steve; Schwartz, David C.

    2012-01-01

    Abstract The Optical Mapping System constructs ordered restriction maps spanning entire genomes through the assembly and analysis of large datasets comprising individually analyzed genomic DNA molecules. Such restriction maps uniquely reveal mammalian genome structure and variation, but also raise computational and statistical questions beyond those that have been solved in the analysis of smaller, microbial genomes. We address the problem of how to filter maps that align poorly to a reference genome. We obtain map-specific thresholds that control errors and improve iterative assembly. We also show how an optimal self-alignment score provides an accurate approximation to the probability of alignment, which is useful in applications seeking to identify structural genomic abnormalities. PMID:22506568

  10. Roles, intents, and actions: First-year teachers' uses of discourse during elementary science instruction

    NASA Astrophysics Data System (ADS)

    Newman, William J., Jr.

    In this study, I examined how three first-year elementary teachers constructed and used classroom discourse during science instruction. The three participants, though graduates from different universities, learned to teach science through similar science methods courses, which stressed the importance of inquiry-based science instruction. The participants taught different grade levels, and two of them taught at the same school. Data sources included field notes, videotapes, audiotapes, and semi-structured teacher interviews. While monologic and dialogic discourse existed in all three classrooms, monologic discourse was more prominent, especially when the discourse was teacher controlled. Dialogic discourse occurred most often during student-centered activities. The teachers constructed discourse with authoritative function to present science content and determine student comprehension. Generative function was most likely during student-based small group discussions. Monologic character often aligned with authoritative function, and dialogic character often aligned with generative function. However, monologic/generative and dialogic/authoritative discourse events did occur, contributing to the development of a discourse theory model. The teacher explanations for discourse included classroom control, inadequate planning, time constraints, life experiences, science education standards, and assessment. The teachers relied on their texts, kits, and state science standards to determine the content and methods for science instruction. They rarely reported that their science methods courses influenced how they taught science. The observed lessons rarely aligned with science education reform descriptions of appropriate science instruction. Implications include the need for in-service programs for beginning science teachers, curricular reform for science texts and kits, and explicit instruction of discourse strategies in science methods courses and in-service programs.

  11. DNA nanotubes for NMR structure determination of membrane proteins.

    PubMed

    Bellot, Gaëtan; McClintock, Mark A; Chou, James J; Shih, William M

    2013-04-01

    Finding a way to determine the structures of integral membrane proteins using solution nuclear magnetic resonance (NMR) spectroscopy has proved to be challenging. A residual-dipolar-coupling-based refinement approach can be used to resolve the structure of membrane proteins up to 40 kDa in size, but to do this you need a weak-alignment medium that is detergent-resistant and it has thus far been difficult to obtain such a medium suitable for weak alignment of membrane proteins. We describe here a protocol for robust, large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into dilute liquid crystals for application as weak-alignment media in solution NMR structure determination of membrane proteins in detergent micelles. The DNA nanotubes are heterodimers of 400-nm-long six-helix bundles, each self-assembled from a M13-based p7308 scaffold strand and >170 short oligonucleotide staple strands. Compatibility with proteins bearing considerable positive charge as well as modulation of molecular alignment, toward collection of linearly independent restraints, can be introduced by reducing the negative charge of DNA nanotubes using counter ions and small DNA-binding molecules. This detergent-resistant liquid-crystal medium offers a number of properties conducive for membrane protein alignment, including high-yield production, thermal stability, buffer compatibility and structural programmability. Production of sufficient nanotubes for four or five NMR experiments can be completed in 1 week by a single individual.

  12. Permanent bending and alignment of ZnO nanowires.

    PubMed

    Borschel, Christian; Spindler, Susann; Lerose, Damiana; Bochmann, Arne; Christiansen, Silke H; Nietzsche, Sandor; Oertel, Michael; Ronning, Carsten

    2011-05-06

    Ion beams can be used to permanently bend and re-align nanowires after growth. We have irradiated ZnO nanowires with energetic ions, achieving bending and alignment in different directions. Not only the bending of single nanowires is studied in detail, but also the simultaneous alignment of large ensembles of ZnO nanowires. Computer simulations reveal how the bending is initiated by ion beam induced damage. Detailed structural characterization identifies dislocations to relax stresses and make the bending and alignment permanent, even surviving annealing procedures.

  13. The hierarchical nature of the spin alignment of dark matter haloes in filaments

    NASA Astrophysics Data System (ADS)

    Aragon-Calvo, M. A.; Yang, Lin Forrest

    2014-05-01

    Dark matter haloes in cosmological filaments and walls have (in average) their spin vector aligned with their host structure. While haloes in walls are aligned with the plane of the wall independently of their mass, haloes in filaments present a mass-dependent two-regime orientation. Here, we show that the transition mass determining the change in the alignment regime (from parallel to perpendicular) depends on the hierarchical level in which the halo is located, reflecting the hierarchical nature of the Cosmic Web. By explicitly exposing the hierarchical structure of the Cosmic Web, we are able to identify the contributions of different components of the filament network to the alignment signal. We propose a unifying picture of angular momentum acquisition that is based on the results presented here and previous results found by other authors. In order to do a hierarchical characterization of the Cosmic Web, we introduce a new implementation of the multiscale morphology filter, the MMF-2, that significantly improves the identification of structures and explicitly describes their hierarchy. L36

  14. Functional annotation by sequence-weighted structure alignments: statistical analysis and case studies from the Protein 3000 structural genomics project in Japan.

    PubMed

    Standley, Daron M; Toh, Hiroyuki; Nakamura, Haruki

    2008-09-01

    A method to functionally annotate structural genomics targets, based on a novel structural alignment scoring function, is proposed. In the proposed score, position-specific scoring matrices are used to weight structurally aligned residue pairs to highlight evolutionarily conserved motifs. The functional form of the score is first optimized for discriminating domains belonging to the same Pfam family from domains belonging to different families but the same CATH or SCOP superfamily. In the optimization stage, we consider four standard weighting functions as well as our own, the "maximum substitution probability," and combinations of these functions. The optimized score achieves an area of 0.87 under the receiver-operating characteristic curve with respect to identifying Pfam families within a sequence-unique benchmark set of domain pairs. Confidence measures are then derived from the benchmark distribution of true-positive scores. The alignment method is next applied to the task of functionally annotating 230 query proteins released to the public as part of the Protein 3000 structural genomics project in Japan. Of these queries, 78 were found to align to templates with the same Pfam family as the query or had sequence identities > or = 30%. Another 49 queries were found to match more distantly related templates. Within this group, the template predicted by our method to be the closest functional relative was often not the most structurally similar. Several nontrivial cases are discussed in detail. Finally, 103 queries matched templates at the fold level, but not the family or superfamily level, and remain functionally uncharacterized. 2008 Wiley-Liss, Inc.

  15. Bayesian comparison of protein structures using partial Procrustes distance.

    PubMed

    Ejlali, Nasim; Faghihi, Mohammad Reza; Sadeghi, Mehdi

    2017-09-26

    An important topic in bioinformatics is the protein structure alignment. Some statistical methods have been proposed for this problem, but most of them align two protein structures based on the global geometric information without considering the effect of neighbourhood in the structures. In this paper, we provide a Bayesian model to align protein structures, by considering the effect of both local and global geometric information of protein structures. Local geometric information is incorporated to the model through the partial Procrustes distance of small substructures. These substructures are composed of β-carbon atoms from the side chains. Parameters are estimated using a Markov chain Monte Carlo (MCMC) approach. We evaluate the performance of our model through some simulation studies. Furthermore, we apply our model to a real dataset and assess the accuracy and convergence rate. Results show that our model is much more efficient than previous approaches.

  16. ITG modes in the presence of inhomogeneous field-aligned flow

    NASA Astrophysics Data System (ADS)

    Sen, S.; McCarthy, D. R.; Lontano, M.; Lazzaro, E.; Honary, F.

    2010-02-01

    In a recent paper, Varischetti et al. (Plasma Phys. Contr. F. 2008, 50, 105008-1-15) have found that in a slab geometry the effect of the flow shear in the field-aligned parallel flow on the linear mode stability of the ion temperature gradient (ITG)-driven modes is not very prominent. They found that the flow shear also has a negligible effect on the mode characteristics. The work in this paper shows that the inclusion of flow curvature in the field-aligned flow can have a considerable effect on the mode stability; it can also change the mode structure so as to effect the mixing length transport in the core region of a fusion device. Flow shear, on the other hand, has indeed an insignificant role in the mode stability and mode structure. Inhomogeneous field-aligned flow should therefore still be considered for a viable candidate in controlling the ITG mode stability and mode structure.

  17. Automatic identification of mobile and rigid substructures in molecular dynamics simulations and fractional structural fluctuation analysis.

    PubMed

    Martínez, Leandro

    2015-01-01

    The analysis of structural mobility in molecular dynamics plays a key role in data interpretation, particularly in the simulation of biomolecules. The most common mobility measures computed from simulations are the Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuations (RMSF) of the structures. These are computed after the alignment of atomic coordinates in each trajectory step to a reference structure. This rigid-body alignment is not robust, in the sense that if a small portion of the structure is highly mobile, the RMSD and RMSF increase for all atoms, resulting possibly in poor quantification of the structural fluctuations and, often, to overlooking important fluctuations associated to biological function. The motivation of this work is to provide a robust measure of structural mobility that is practical, and easy to interpret. We propose a Low-Order-Value-Optimization (LOVO) strategy for the robust alignment of the least mobile substructures in a simulation. These substructures are automatically identified by the method. The algorithm consists of the iterative superposition of the fraction of structure displaying the smallest displacements. Therefore, the least mobile substructures are identified, providing a clearer picture of the overall structural fluctuations. Examples are given to illustrate the interpretative advantages of this strategy. The software for performing the alignments was named MDLovoFit and it is available as free-software at: http://leandro.iqm.unicamp.br/mdlovofit.

  18. Automatic Identification of Mobile and Rigid Substructures in Molecular Dynamics Simulations and Fractional Structural Fluctuation Analysis

    PubMed Central

    Martínez, Leandro

    2015-01-01

    The analysis of structural mobility in molecular dynamics plays a key role in data interpretation, particularly in the simulation of biomolecules. The most common mobility measures computed from simulations are the Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuations (RMSF) of the structures. These are computed after the alignment of atomic coordinates in each trajectory step to a reference structure. This rigid-body alignment is not robust, in the sense that if a small portion of the structure is highly mobile, the RMSD and RMSF increase for all atoms, resulting possibly in poor quantification of the structural fluctuations and, often, to overlooking important fluctuations associated to biological function. The motivation of this work is to provide a robust measure of structural mobility that is practical, and easy to interpret. We propose a Low-Order-Value-Optimization (LOVO) strategy for the robust alignment of the least mobile substructures in a simulation. These substructures are automatically identified by the method. The algorithm consists of the iterative superposition of the fraction of structure displaying the smallest displacements. Therefore, the least mobile substructures are identified, providing a clearer picture of the overall structural fluctuations. Examples are given to illustrate the interpretative advantages of this strategy. The software for performing the alignments was named MDLovoFit and it is available as free-software at: http://leandro.iqm.unicamp.br/mdlovofit PMID:25816325

  19. XML schemas for common bioinformatic data types and their application in workflow systems.

    PubMed

    Seibel, Philipp N; Krüger, Jan; Hartmeier, Sven; Schwarzer, Knut; Löwenthal, Kai; Mersch, Henning; Dandekar, Thomas; Giegerich, Robert

    2006-11-06

    Today, there is a growing need in bioinformatics to combine available software tools into chains, thus building complex applications from existing single-task tools. To create such workflows, the tools involved have to be able to work with each other's data--therefore, a common set of well-defined data formats is needed. Unfortunately, current bioinformatic tools use a great variety of heterogeneous formats. Acknowledging the need for common formats, the Helmholtz Open BioInformatics Technology network (HOBIT) identified several basic data types used in bioinformatics and developed appropriate format descriptions, formally defined by XML schemas, and incorporated them in a Java library (BioDOM). These schemas currently cover sequence, sequence alignment, RNA secondary structure and RNA secondary structure alignment formats in a form that is independent of any specific program, thus enabling seamless interoperation of different tools. All XML formats are available at http://bioschemas.sourceforge.net, the BioDOM library can be obtained at http://biodom.sourceforge.net. The HOBIT XML schemas and the BioDOM library simplify adding XML support to newly created and existing bioinformatic tools, enabling these tools to interoperate seamlessly in workflow scenarios.

  20. The Search for Astronomical Alignments in the Seventh Century A.D. Silla Capital at Kyongju, Korea

    NASA Astrophysics Data System (ADS)

    Nelson, S. M.; Stencel, R. E.

    1999-05-01

    In the center of the modern Korean city of Kyongju stands a modest structure dating from the 7th century AD, known as Chomsongdae, or the Star Observatory. Known locally as the oldest observatory in Asia, details of its precise use are lost, but its construction coincided with the height of Silla culture and its dominance over the Korean peninsula. Radially from the structure are located the so-called Moon Fortress, numerous large tombsites for elite of the culture, plus hillside fortresses and elaborate Buddhist temples. During 1999, we've conducted a course at Denver as part of our Core Curriculum program for The Women's College, that has examined the astronomical and cultural aspects of the Kyongju site, to attempt to determine whether the architects may have included astronomical alignments into the ``Feng Shui" of their city planning, spanning centuries. The preliminary result of our studies suggests that east and west of Star Observatory lay fortress and wall features that may have been useful for equinox determination. A discussion of ethnographic supporting evidence will be provided, but additional on-site observations will be needed to confirm the idea.

  1. Fast 3D shape screening of large chemical databases through alignment-recycling

    PubMed Central

    Fontaine, Fabien; Bolton, Evan; Borodina, Yulia; Bryant, Stephen H

    2007-01-01

    Background Large chemical databases require fast, efficient, and simple ways of looking for similar structures. Although such tasks are now fairly well resolved for graph-based similarity queries, they remain an issue for 3D approaches, particularly for those based on 3D shape overlays. Inspired by a recent technique developed to compare molecular shapes, we designed a hybrid methodology, alignment-recycling, that enables efficient retrieval and alignment of structures with similar 3D shapes. Results Using a dataset of more than one million PubChem compounds of limited size (< 28 heavy atoms) and flexibility (< 6 rotatable bonds), we obtained a set of a few thousand diverse structures covering entirely the 3D shape space of the conformers of the dataset. Transformation matrices gathered from the overlays between these diverse structures and the 3D conformer dataset allowed us to drastically (100-fold) reduce the CPU time required for shape overlay. The alignment-recycling heuristic produces results consistent with de novo alignment calculation, with better than 80% hit list overlap on average. Conclusion Overlay-based 3D methods are computationally demanding when searching large databases. Alignment-recycling reduces the CPU time to perform shape similarity searches by breaking the alignment problem into three steps: selection of diverse shapes to describe the database shape-space; overlay of the database conformers to the diverse shapes; and non-optimized overlay of query and database conformers using common reference shapes. The precomputation, required by the first two steps, is a significant cost of the method; however, once performed, querying is two orders of magnitude faster. Extensions and variations of this methodology, for example, to handle more flexible and larger small-molecules are discussed. PMID:17880744

  2. Electric-Field-Induced Alignment of Block Copolymer/Nanoparticle Blends

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liedel, Clemens; Schindler, Kerstin; Pavan, Mariela J.

    External electric fi elds readily align birefringent block-copolymer mesophases. In this study the effect of gold nanoparticles on the electric-fi eld-induced alignment of a lamellae-forming polystyrene- block -poly(2-vinylpyridine) copolymer is assessed. Nanoparticles are homogeneously dispersed in the styrenic phase and promote the quantitative alignment of lamellar domains by substantially lowering the critical field strength above which alignment proceeds. The results suggest that the electric-fi eldassisted alignment of nanostructured block copolymer/nanoparticle composites may offer a simple way to greatly mitigate structural and orientational defects of such fi lms under benign experimental conditions.

  3. Heavy Lift Helicopter - Cargo Handling ATC Program. Volume I. Detail Design Structural and Weights Analysis, and Static and Dynamic Load Analysis

    DTIC Science & Technology

    1976-01-01

    a load cell for axial load sensing. The cylindrical spring fluid housing has a self-aligning bearing installed to suit the hoist rtounting provisions...PA dJ A L4 * f5 W 7 1 ~~t~ j"H2 j "xioA"AUSCCRCO El4 "sV. 10% PLA VIE - C : NJrAUk ATK ON AA U - . j4 5’ c IIf -O a ¶ .. ~~r~eF ON *A *~ A*WMA &fi

  4. Impact of Information Technology Governance Structures on Strategic Alignment

    ERIC Educational Resources Information Center

    Gordon, Fitzroy R.

    2013-01-01

    This dissertation is a study of the relationship between Information Technology (IT) strategic alignment and IT governance structure within the organization. This dissertation replicates Asante (2010) among a different population where the prior results continue to hold, the non-experimental approach explored two research questions but include two…

  5. Structural alignment sensor. [laser applications and interferometry

    NASA Technical Reports Server (NTRS)

    Davis, L.; Buholz, N. E.; Gillard, C. W.; Huang, C. C.; Wells, W. M., III

    1978-01-01

    Comparative Michelson interferometers are discussed as well as the operating range potential of a structural alignment sensor (SAS) which requires only one laser mode. Schematics are presented for the distance measurement logic, the basic SAS system, the SAS optical layout, the coarse measurement signal processor, and the measured range resolution.

  6. Developing Secure Power Systems Professional Competence: Alignment and Gaps in Workforce Development Programs—Summary Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Neil, Lori Ross; Assante, Michael; Tobey, D. H.

    2013-07-01

    This document is a summarization of the report, Developing Secure Power Systems Professional Competence: Alignment and Gaps in Workforce Development Programs, the final report for phase 2 of the SPSP (DOE workforce study) project.

  7. Rclick: a web server for comparison of RNA 3D structures.

    PubMed

    Nguyen, Minh N; Verma, Chandra

    2015-03-15

    RNA molecules play important roles in key biological processes in the cell and are becoming attractive for developing therapeutic applications. Since the function of RNA depends on its structure and dynamics, comparing and classifying the RNA 3D structures is of crucial importance to molecular biology. In this study, we have developed Rclick, a web server that is capable of superimposing RNA 3D structures by using clique matching and 3D least-squares fitting. Our server Rclick has been benchmarked and compared with other popular servers and methods for RNA structural alignments. In most cases, Rclick alignments were better in terms of structure overlap. Our server also recognizes conformational changes between structures. For this purpose, the server produces complementary alignments to maximize the extent of detectable similarity. Various examples showcase the utility of our web server for comparison of RNA, RNA-protein complexes and RNA-ligand structures. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. cljam: a library for handling DNA sequence alignment/map (SAM) with parallel processing.

    PubMed

    Takeuchi, Toshiki; Yamada, Atsuo; Aoki, Takashi; Nishimura, Kunihiro

    2016-01-01

    Next-generation sequencing can determine DNA bases and the results of sequence alignments are generally stored in files in the Sequence Alignment/Map (SAM) format and the compressed binary version (BAM) of it. SAMtools is a typical tool for dealing with files in the SAM/BAM format. SAMtools has various functions, including detection of variants, visualization of alignments, indexing, extraction of parts of the data and loci, and conversion of file formats. It is written in C and can execute fast. However, SAMtools requires an additional implementation to be used in parallel with, for example, OpenMP (Open Multi-Processing) libraries. For the accumulation of next-generation sequencing data, a simple parallelization program, which can support cloud and PC cluster environments, is required. We have developed cljam using the Clojure programming language, which simplifies parallel programming, to handle SAM/BAM data. Cljam can run in a Java runtime environment (e.g., Windows, Linux, Mac OS X) with Clojure. Cljam can process and analyze SAM/BAM files in parallel and at high speed. The execution time with cljam is almost the same as with SAMtools. The cljam code is written in Clojure and has fewer lines than other similar tools.

  9. Filament Winding Multifunctional Carbon Nanotube Composites of Various Dimensionality

    NASA Astrophysics Data System (ADS)

    Wells, Brian David

    Carbon nanotubes (CNT) have been long considered an optimal material for composites due to their high strength, high modulus, and electrical/thermal conductivity. These composite materials have the potential to be used in the aerospace, computer, automotive, medical industry as well as many others. The nano dimensions of these structures make controlled alignment and distribution difficult using many production techniques. An area that shows promise for controlled alignment is the formation of CNT yarns. Different approaches have been used to create yarns with various winding angles and diameters. CNTs resemble traditional textile fiber structures due to their one-dimensional dimensions, axial strength and radial flexibility. One difference is, depending on the length, CNTs can have aspect ratios that far exceed those of traditional textile fibers. This can complicate processing techniques and cause agglomeration which prevents optimal structures from being created. However, with specific aspect ratios and spatial distributions a specific type of CNT, vertically aligned spinnable carbon nanotubes (VASCNTs), have interesting properties that allow carbon nanotubes to be drawn from an array in a continuous aligned web. This dissertation examines the feasibility of combining VASCNTs with another textile manufacturing process, filament winding, to create structures with various levels of dimensionality. While yarn formation with CNTs has been largely studied, there has not been significant work studying the use of VASCNTs to create composite materials. The studies that have been produces revolve around mixing CNTs into epoxy or creating uni-directional wound structures. In this dissertation VASCNTs are used to create filament wound materials with various degrees of alignment. These structures include 1 dimensional coatings applied to non-conductive polymer monofilaments, two dimensional multifunctional adhesive films, and three dimensional hybrid-nano composites. The angle of alignment between the individual CNTs relative to the overall structure was used to affect the electrical properties in all of these structures and the mechanical properties of the adhesive films and hybrid-nano composites. Varying the concentration of CNT was also found to have a significant effect on the electrical and mechanical properties. The variable properties that can be created with these production techniques allow users to engineer the structure to match the desired property.

  10. Flexible and Lightweight Pressure Sensor Based on Carbon Nanotube/Thermoplastic Polyurethane-Aligned Conductive Foam with Superior Compressibility and Stability.

    PubMed

    Huang, Wenju; Dai, Kun; Zhai, Yue; Liu, Hu; Zhan, Pengfei; Gao, Jiachen; Zheng, Guoqiang; Liu, Chuntai; Shen, Changyu

    2017-12-06

    Flexible and lightweight carbon nanotube (CNT)/thermoplastic polyurethane (TPU) conductive foam with a novel aligned porous structure was fabricated. The density of the aligned porous material was as low as 0.123 g·cm -3 . Homogeneous dispersion of CNTs was achieved through the skeleton of the foam, and an ultralow percolation threshold of 0.0023 vol % was obtained. Compared with the disordered foam, mechanical properties of the aligned foam were enhanced and the piezoresistive stability of the flexible foam was improved significantly. The compression strength of the aligned TPU foam increases by 30.7% at the strain of 50%, and the stress of the aligned foam is 22 times that of the disordered foam at the strain of 90%. Importantly, the resistance variation of the aligned foam shows a fascinating linear characteristic under the applied strain until 77%, which would benefit the application of the foam as a desired pressure sensor. During multiple cyclic compression-release measurements, the aligned conductive CNT/TPU foam represents excellent reversibility and reproducibility in terms of resistance. This nice capability benefits from the aligned porous structure composed of ladderlike cells along the orientation direction. Simultaneously, the human motion detections, such as walk, jump, squat, etc. were demonstrated by using our flexible pressure sensor. Because of the lightweight, flexibility, high compressibility, excellent reversibility, and reproducibility of the conductive aligned foam, the present study is capable of providing new insights into the fabrication of a high-performance pressure sensor.

  11. Depot Acquisition Management and Engineering Support for Close-in Weapon System (CIWS) Phalanx Mk 15 and FCS Mk 92/Gun Mount Mk 75 Overhaul Programs.

    DTIC Science & Technology

    1980-12-01

    fProgram SI- nsor CNC ’ OF- 3’ 4 Proqram Director SEA-62Y GWS Maintcenance Manaqer isroan -S E A -6 2 Y CC W r q a Organic Marager SfEA6Y Failure Data...alignment. (e) Pres-sure containing part.s. Wall thickness (thinnest area, erosior. lath , or both) and leakage rate. f) Couplings and shafts. Alignment and

  12. Study on the key alignment technology of the catadioptric optical system

    NASA Astrophysics Data System (ADS)

    Song, Chong; Fu, Xing; Fu, Xi-hong; Kang, Xiao-peng; Liu, Kai

    2017-02-01

    Optical system alignment has a great influence on the whole system accuracy. In this paper, the processing of optical system alignment was mainly studied, the processing method of optics on the primary and secondary mirrors, front correction lens group and behind correction lens group with high precision centering lathe and internal focusing telescope. Then using the height indicator complete the system alignment of the primary mirror, secondary mirror, front correction group and behind correction group. Finally, based on the zygo interferometer detect the wavefront information. Using this alignment program for catadioptric optical system, the wavefront aberration of optical system, focal length, modulation transfer function (MTF) and other technical indicators have reached the requirements.

  13. Adaptable liquid crystal elastomers with transesterification-based bond exchange reactions.

    PubMed

    Hanzon, Drew W; Traugutt, Nicholas A; McBride, Matthew K; Bowman, Christopher N; Yakacki, Christopher M; Yu, Kai

    2018-02-14

    Adaptable liquid crystal elastomers (LCEs) have recently emerged to provide a new and robust method to program monodomain LCE samples. When a constant stress is applied with active bond exchange reactions (BERs), polymer chains and mesogens gradually align in the strain direction. Mesogen alignment is maintained after removing the BER stimulus (e.g. by lowering the temperature) and the programmed LCE samples exhibit free-standing two-way shape switching behavior. Here, a new adaptable main-chain LCE system was developed with thermally induced transesterification BERs. The network combines the conventional properties of LCEs, such as an isotropic phase transition and soft elasticity, with the dynamic features of adaptable network polymers, which are malleable to stress relaxation due to the BERs. Polarized Fourier transform infrared measurements confirmed the alignment of polymer chains and mesogens after strain-induced programming. The influence of the creep stress, temperature, and time on the strain amplitude of two-way shape switching was examined. The LCE network demonstrates an innovative feature of reprogrammability, where the reversible shape-switching memory of programmed LCEs is readily deleted by free-standing heating as random BERs disrupt the mesogen alignment, so LCEs are reprogrammed after returning to the polydomain state. Due to the dynamic nature of the LCE network, it also exhibits a surface welding effect and can be fully dissolved in the organic solvent, which might be utilized for green and sustainable recycling of LCEs.

  14. Preparation of Nanocomposite Plasmonic Films Made from Cellulose Nanocrystals or Mesoporous Silica Decorated with Unidirectionally Aligned Gold Nanorods.

    PubMed

    Campbell, Michael G; Liu, Qingkun; Sanders, Aric; Evans, Julian S; Smalyukh, Ivan I

    2014-04-11

    Using liquid crystalline self-assembly of cellulose nanocrystals, we achieve long-range alignment of anisotropic metal nanoparticles in colloidal nanocrystal dispersions that are then used to deposit thin structured films with ordering features highly dependent on the deposition method. These hybrid films are comprised of gold nanorods unidirectionally aligned in a matrix that can be made of ordered cellulose nanocrystals or silica nanostructures obtained by using cellulose-based nanostructures as a replica. The ensuing long-range alignment of gold nanorods in both cellulose-based and nanoporous silica films results in a polarization-sensitive surface plasmon resonance. The demonstrated device-scale bulk nanoparticle alignment may enable engineering of new material properties arising from combining the orientational ordering of host nanostructures and properties of the anisotropic plasmonic metal nanoparticles. Our approach may also allow for scalable fabrication of plasmonic polarizers and nanoporous silica structures with orientationally ordered anisotropic plasmonic nanoinclusions.

  15. Magnetic field effect for cellulose nanofiber alignment

    NASA Astrophysics Data System (ADS)

    Kim, Jaehwan; Chen, Yi; Kang, Kwang-Sun; Park, Young-Bin; Schwartz, Mark

    2008-11-01

    Regenerated cellulose formed into cellulose nanofibers under strong magnetic field and aligned perpendicularly to the magnetic field. Well-aligned microfibrils were found as the exposure time of the magnetic field increased. Better alignment and more crystalline structure of the cellulose resulted in the increased decomposition temperature of the material. X-ray crystallograms showed that crystallinity index of the cellulose increased as the exposure time of the magnetic field increased.

  16. Interactive Alignment of Multisyllabic Stress Patterns in a Second Language Classroom

    ERIC Educational Resources Information Center

    Trofimovich, Pavel; McDonough, Kim; Foote, Jennifer A.

    2014-01-01

    The current study explored the occurrence of stress pattern alignment during peer interaction in a second language (L2) classroom. Interactive alignment is a sociocognitive phenomenon in which interlocutors reuse each other's expressions, structures, and pronunciation patterns during conversation. Students (N = 41) enrolled in a…

  17. Use cases and DEMO: aligning functional features of ICT-infrastructure to business processes.

    PubMed

    Maij, E; Toussaint, P J; Kalshoven, M; Poerschke, M; Zwetsloot-Schonk, J H M

    2002-11-12

    The proper alignment of functional features of the ICT-infrastructure to business processes is a major challenge in health care organisations. This alignment takes into account that the organisational structure not only shapes the ICT-infrastructure, but that the inverse also holds. To solve the alignment problem, relevant features of the ICT-infrastructure should be derived from the organisational structure and the influence of this envisaged ICT to the work practices should be pointed out. The objective of our study was to develop a method to solve this alignment problem. In a previous study we demonstrated the appropriateness of the business process modelling methodology Dynamic Essential Modelling of Organizations (DEMO). A proven and widely used modelling language for expressing functional features is Unified Modelling Language (UML). In the context of a specific case study at the University Medical Centre Utrecht in the Netherlands we investigated if the combined use of DEMO and UML could solve the alignment problem. The study demonstrated that the DEMO models were suited as a starting point in deriving system functionality by using the use case concept of UML. Further, the case study demonstrated that in using this approach for the alignment problem, insight is gained into the mutual influence of ICT-infrastructure and organisation structure: (a) specification of independent, re-usable components-as a set of related functionalities-is realised, and (b) a helpful representation of the current and future work practice is provided for in relation to the envisaged ICT support.

  18. Development and application of an algorithm to compute weighted multiple glycan alignments.

    PubMed

    Hosoda, Masae; Akune, Yukie; Aoki-Kinoshita, Kiyoko F

    2017-05-01

    A glycan consists of monosaccharides linked by glycosidic bonds, has branches and forms complex molecular structures. Databases have been developed to store large amounts of glycan-binding experiments, including glycan arrays with glycan-binding proteins. However, there are few bioinformatics techniques to analyze large amounts of data for glycans because there are few tools that can handle the complexity of glycan structures. Thus, we have developed the MCAW (Multiple Carbohydrate Alignment with Weights) tool that can align multiple glycan structures, to aid in the understanding of their function as binding recognition molecules. We have described in detail the first algorithm to perform multiple glycan alignments by modeling glycans as trees. To test our tool, we prepared several data sets, and as a result, we found that the glycan motif could be successfully aligned without any prior knowledge applied to the tool, and the known recognition binding sites of glycans could be aligned at a high rate amongst all our datasets tested. We thus claim that our tool is able to find meaningful glycan recognition and binding patterns using data obtained by glycan-binding experiments. The development and availability of an effective multiple glycan alignment tool opens possibilities for many other glycoinformatics analysis, making this work a big step towards furthering glycomics analysis. http://www.rings.t.soka.ac.jp. kkiyoko@soka.ac.jp. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

  19. Effect of mat pilates exercise on postural alignment and body composition of middle-aged women.

    PubMed

    Lee, Hyo Taek; Oh, Hyun Ok; Han, Hui Seung; Jin, Kwang Youn; Roh, Hyo Lyun

    2016-06-01

    [Purpose] This study attempted to examine whether Pilates is an effective exercise for improving the postural alignment and health of middle-aged women. [Subjects and Methods] The participants in this study were 36 middle-aged women (20 in the experimental group, 16 in the control group). The experimental group participated in Pilates exercise sessions three times a week for 12 weeks. Body alignment and composition measurements before and after applying the Pilates exercise program were performed with a body composition analyzer and a three-dimensional scanner. [Results] Postural alignment in the sagittal and horizontal planes was enhanced in the Pilates exercise group. Trunk alignment showed correlations with body fat and muscle mass. [Conclusion] The Pilates exercises are performed symmetrically and strengthen the deep muscles. Moreover, the results showed that muscle mass was correlated with trunk postural alignment and that the proper amount of muscle is critical in maintaining trunk postural alignment.

  20. Molecular systematics of terraranas (Anura: Brachycephaloidea) with an assessment of the effects of alignment and optimality criteria.

    PubMed

    Padial, José M; Grant, Taran; Frost, Darrel R

    2014-06-26

    Brachycephaloidea is a monophyletic group of frogs with more than 1000 species distributed throughout the New World tropics, subtropics, and Andean regions. Recently, the group has been the target of multiple molecular phylogenetic analyses, resulting in extensive changes in its taxonomy. Here, we test previous hypotheses of phylogenetic relationships for the group by combining available molecular evidence (sequences of 22 genes representing 431 ingroup and 25 outgroup terminals) and performing a tree-alignment analysis under the parsimony optimality criterion using the program POY. To elucidate the effects of alignment and optimality criterion on phylogenetic inferences, we also used the program MAFFT to obtain a similarity-alignment for analysis under both parsimony and maximum likelihood using the programs TNT and GARLI, respectively. Although all three analytical approaches agreed on numerous points, there was also extensive disagreement. Tree-alignment under parsimony supported the monophyly of the ingroup and the sister group relationship of the monophyletic marsupial frogs (Hemiphractidae), while maximum likelihood and parsimony analyses of the MAFFT similarity-alignment did not. All three methods differed with respect to the position of Ceuthomantis smaragdinus (Ceuthomantidae), with tree-alignment using parsimony recovering this species as the sister of Pristimantis + Yunganastes. All analyses rejected the monophyly of Strabomantidae and Strabomantinae as originally defined, and the tree-alignment analysis under parsimony further rejected the recently redefined Craugastoridae and Pristimantinae. Despite the greater emphasis in the systematics literature placed on the choice of optimality criterion for evaluating trees than on the choice of method for aligning DNA sequences, we found that the topological differences attributable to the alignment method were as great as those caused by the optimality criterion. Further, the optimal tree-alignment indicates that insertions and deletions occurred in twice as many aligned positions as implied by the optimal similarity-alignment, confirming previous findings that sequence turnover through insertion and deletion events plays a greater role in molecular evolution than indicated by similarity-alignments. Our results also provide a clear empirical demonstration of the different effects of wildcard taxa produced by missing data in parsimony and maximum likelihood analyses. Specifically, maximum likelihood analyses consistently (81% bootstrap frequency) provided spurious resolution despite a lack of evidence, whereas parsimony correctly depicted the ambiguity due to missing data by collapsing unsupported nodes. We provide a new taxonomy for the group that retains previously recognized Linnaean taxa except for Ceuthomantidae, Strabomantidae, and Strabomantinae. A phenotypically diagnosable superfamily is recognized formally as Brachycephaloidea, with the informal, unranked name terrarana retained as the standard common name for these frogs. We recognize three families within Brachycephaloidea that are currently diagnosable solely on molecular grounds (Brachycephalidae, Craugastoridae, and Eleutherodactylidae), as well as five subfamilies (Craugastorinae, Eleutherodactylinae, Holoadeninae, Phyzelaphryninae, and Pristimantinae) corresponding in large part to previous families and subfamilies. Our analyses upheld the monophyly of all tested genera, but we found numerous subgeneric taxa to be non-monophyletic and modified the taxonomy accordingly.

  1. Automatic alignment of double optical paths in excimer laser amplifier

    NASA Astrophysics Data System (ADS)

    Wang, Dahui; Zhao, Xueqing; Hua, Hengqi; Zhang, Yongsheng; Hu, Yun; Yi, Aiping; Zhao, Jun

    2013-05-01

    A kind of beam automatic alignment method used for double paths amplification in the electron pumped excimer laser system is demonstrated. In this way, the beams from the amplifiers can be transferred along the designated direction and accordingly irradiate on the target with high stabilization and accuracy. However, owing to nonexistence of natural alignment references in excimer laser amplifiers, two cross-hairs structure is used to align the beams. Here, one crosshair put into the input beam is regarded as the near-field reference while the other put into output beam is regarded as the far-field reference. The two cross-hairs are transmitted onto Charge Coupled Devices (CCD) by image-relaying structures separately. The errors between intersection points of two cross-talk images and centroid coordinates of actual beam are recorded automatically and sent to closed loop feedback control mechanism. Negative feedback keeps running until preset accuracy is reached. On the basis of above-mentioned design, the alignment optical path is built and the software is compiled, whereafter the experiment of double paths automatic alignment in electron pumped excimer laser amplifier is carried through. Meanwhile, the related influencing factors and the alignment precision are analyzed. Experimental results indicate that the alignment system can achieve the aiming direction of automatic aligning beams in short time. The analysis shows that the accuracy of alignment system is 0.63μrad and the beam maximum restoration error is 13.75μm. Furthermore, the bigger distance between the two cross-hairs, the higher precision of the system is. Therefore, the automatic alignment system has been used in angular multiplexing excimer Main Oscillation Power Amplification (MOPA) system and can satisfy the requirement of beam alignment precision on the whole.

  2. Judging Surgical Research: How Should We Evaluate Performance and Measure Value?

    PubMed Central

    Souba, Wiley W.; Wilmore, Douglas W.

    2000-01-01

    Objective To establish criteria to evaluate performance in surgical research, and to suggest strategies to optimize research in the future. Summary Background Data Research is an integral component of the academic mission, focusing on important clinical problems, accounting for surgical advances, and providing training and mentoring for young surgeons. With constraints on healthcare resources, there is increasing pressure to generate clinical revenues at the expense of the time and effort devoted to surgical research. An approach that would assess the value of research would allow prioritization of projects. Further, alignment of high-priority research projects with clinical goals would optimize research gains and maximize the clinical enterprise. Methods The authors reviewed performance criteria applied to industrial research and modified these criteria to apply to surgical research. They reviewed several programs that align research objectives with clinical goals. Results Performance criteria were categorized along several dimensions: internal measures (quality, productivity, innovation, learning, and development), customer satisfaction, market share, and financial indices (cost and profitability). A “report card” was proposed to allow the assessment of research in an individual department or division. Conclusions The department’s business strategy can no longer be divorced from its research strategy. Alignment between research and clinical goals will maximize the department’s objectives but will create the need to modify existing hierarchical structures and reward systems. Such alignment appears to be the best way to ensure the success of surgical research in the future. PMID:10862192

  3. BIOPEP database and other programs for processing bioactive peptide sequences.

    PubMed

    Minkiewicz, Piotr; Dziuba, Jerzy; Iwaniak, Anna; Dziuba, Marta; Darewicz, Małgorzata

    2008-01-01

    This review presents the potential for application of computational tools in peptide science based on a sample BIOPEP database and program as well as other programs and databases available via the World Wide Web. The BIOPEP application contains a database of biologically active peptide sequences and a program enabling construction of profiles of the potential biological activity of protein fragments, calculation of quantitative descriptors as measures of the value of proteins as potential precursors of bioactive peptides, and prediction of bonds susceptible to hydrolysis by endopeptidases in a protein chain. Other bioactive and allergenic peptide sequence databases are also presented. Programs enabling the construction of binary and multiple alignments between peptide sequences, the construction of sequence motifs attributed to a given type of bioactivity, searching for potential precursors of bioactive peptides, and the prediction of sites susceptible to proteolytic cleavage in protein chains are available via the Internet as are other approaches concerning secondary structure prediction and calculation of physicochemical features based on amino acid sequence. Programs for prediction of allergenic and toxic properties have also been developed. This review explores the possibilities of cooperation between various programs.

  4. An 8-week thoracic spine stabilization exercise program improves postural back pain, spine alignment, postural sway, and core endurance in university students:a randomized controlled study.

    PubMed

    Toprak Çelenay, Şeyda; Özer Kaya, Derya

    2017-04-18

    To investigate the effects of an 8-week thoracic stabilization exercise program on back pain, spinal alignment, postural sway, and core endurance in university students. University students were randomly allocated into exercise (n: 28) and control (n: 25) groups. The exercise program was carried out 3 days a week for 8 weeks. Postural pain, spinal alignment, postural sway, and core endurance were assessed via visual analogue scale, Spinal Mouse, Biodex Balance System, and McGill's trunk muscle endurance tests at the baseline and after 8 weeks of training. Differences were observed for postural pain, thoracic and lumbar curvature, dynamic stability index (eyes closed), and core endurance scores in the exercise group between baseline and week 8 (P < 0.05) and all the parameters were significantly different when compared to those of the control group (P < 0.05). The program decreased postural pain, spinal curvatures, and postural sway, and increased core endurance in university students. The program can be effective in postural pain and misalignment of spine problems related to core weakness and balance disorders.

  5. How the Avahan HIV prevention program transitioned from the Gates Foundation to the government of India.

    PubMed

    Sgaier, Sema K; Ramakrishnan, Aparajita; Dhingra, Neeraj; Wadhwani, Alkesh; Alexander, Ashok; Bennett, Sara; Bhalla, Aparajita; Kumta, Sameer; Jayaram, Matangi; Gupta, Pankaj; Piot, Peter K; Bertozzi, Stefano M; Anthony, John

    2013-07-01

    Developing countries face diminishing development aid and time-limited donor commitments that challenge the long-term sustainability of donor-funded programs to improve the health of local populations. Increasing country ownership of the programs is one solution. Transitioning managerial and financial responsibility for donor-funded programs to governments and local stakeholders represents a highly advanced form of country ownership, but there are few successful examples among large-scale programs. We present a transition framework and describe how it was used to transfer the Bill & Melinda Gates Foundation's HIV/AIDS prevention program, the Avahan program, to the Government of India. Essential features recommended for the transition of donor-funded programs to governments include early planning with the government, aligning donor program components with government structures and funding models prior to transition, building government capacity through active technical and management support, budgeting for adequate support during and after the transition, and dividing the transition into phases to allow time for adjustments and corrections. The transition of programs to governments is an important sustainability strategy for efforts to scale up HIV prevention programs to reach the populations most at risk.

  6. LiveBench-1: continuous benchmarking of protein structure prediction servers.

    PubMed

    Bujnicki, J M; Elofsson, A; Fischer, D; Rychlewski, L

    2001-02-01

    We present a novel, continuous approach aimed at the large-scale assessment of the performance of available fold-recognition servers. Six popular servers were investigated: PDB-Blast, FFAS, T98-lib, GenTHREADER, 3D-PSSM, and INBGU. The assessment was conducted using as prediction targets a large number of selected protein structures released from October 1999 to April 2000. A target was selected if its sequence showed no significant similarity to any of the proteins previously available in the structural database. Overall, the servers were able to produce structurally similar models for one-half of the targets, but significantly accurate sequence-structure alignments were produced for only one-third of the targets. We further classified the targets into two sets: easy and hard. We found that all servers were able to find the correct answer for the vast majority of the easy targets if a structurally similar fold was present in the server's fold libraries. However, among the hard targets--where standard methods such as PSI-BLAST fail--the most sensitive fold-recognition servers were able to produce similar models for only 40% of the cases, half of which had a significantly accurate sequence-structure alignment. Among the hard targets, the presence of updated libraries appeared to be less critical for the ranking. An "ideally combined consensus" prediction, where the results of all servers are considered, would increase the percentage of correct assignments by 50%. Each server had a number of cases with a correct assignment, where the assignments of all the other servers were wrong. This emphasizes the benefits of considering more than one server in difficult prediction tasks. The LiveBench program (http://BioInfo.PL/LiveBench) is being continued, and all interested developers are cordially invited to join.

  7. Transitioning a Large Scale HIV/AIDS Prevention Program to Local Stakeholders: Findings from the Avahan Transition Evaluation

    PubMed Central

    Bennett, Sara; Singh, Suneeta; Rodriguez, Daniela; Ozawa, Sachiko; Singh, Kriti; Chhabra, Vibha; Dhingra, Neeraj

    2015-01-01

    Background Between 2009–2013 the Bill and Melinda Gates Foundation transitioned its HIV/AIDS prevention initiative in India from being a stand-alone program outside of government, to being fully government funded and implemented. We present an independent prospective evaluation of the transition. Methods The evaluation drew upon (1) a structured survey of transition readiness in a sample of 80 targeted HIV prevention programs prior to transition; (2) a structured survey assessing institutionalization of program features in a sample of 70 targeted intervention (TI) programs, one year post-transition; and (3) case studies of 15 TI programs. Findings Transition was conducted in 3 rounds. While the 2009 transition round was problematic, subsequent rounds were implemented more smoothly. In the 2011 and 2012 transition rounds, Avahan programs were well prepared for transition with the large majority of TI program staff trained for transition, high alignment with government clinical, financial and managerial norms, and strong government commitment to the program. One year post transition there were significant program changes, but these were largely perceived positively. Notable negative changes were: limited flexibility in program management, delays in funding, commodity stock outs, and community member perceptions of a narrowing in program focus. Service coverage outcomes were sustained at least six months post-transition. Interpretation The study suggests that significant investments in transition preparation contributed to a smooth transition and sustained service coverage. Notwithstanding, there were substantive program changes post-transition. Five key lessons for transition design and implementation are identified. PMID:26327591

  8. A new graph-based method for pairwise global network alignment

    PubMed Central

    Klau, Gunnar W

    2009-01-01

    Background In addition to component-based comparative approaches, network alignments provide the means to study conserved network topology such as common pathways and more complex network motifs. Yet, unlike in classical sequence alignment, the comparison of networks becomes computationally more challenging, as most meaningful assumptions instantly lead to NP-hard problems. Most previous algorithmic work on network alignments is heuristic in nature. Results We introduce the graph-based maximum structural matching formulation for pairwise global network alignment. We relate the formulation to previous work and prove NP-hardness of the problem. Based on the new formulation we build upon recent results in computational structural biology and present a novel Lagrangian relaxation approach that, in combination with a branch-and-bound method, computes provably optimal network alignments. The Lagrangian algorithm alone is a powerful heuristic method, which produces solutions that are often near-optimal and – unlike those computed by pure heuristics – come with a quality guarantee. Conclusion Computational experiments on the alignment of protein-protein interaction networks and on the classification of metabolic subnetworks demonstrate that the new method is reasonably fast and has advantages over pure heuristics. Our software tool is freely available as part of the LISA library. PMID:19208162

  9. ProfileGrids: a sequence alignment visualization paradigm that avoids the limitations of Sequence Logos.

    PubMed

    Roca, Alberto I

    2014-01-01

    The 2013 BioVis Contest provided an opportunity to evaluate different paradigms for visualizing protein multiple sequence alignments. Such data sets are becoming extremely large and thus taxing current visualization paradigms. Sequence Logos represent consensus sequences but have limitations for protein alignments. As an alternative, ProfileGrids are a new protein sequence alignment visualization paradigm that represents an alignment as a color-coded matrix of the residue frequency occurring at every homologous position in the aligned protein family. The JProfileGrid software program was used to analyze the BioVis contest data sets to generate figures for comparison with the Sequence Logo reference images. The ProfileGrid representation allows for the clear and effective analysis of protein multiple sequence alignments. This includes both a general overview of the conservation and diversity sequence patterns as well as the interactive ability to query the details of the protein residue distributions in the alignment. The JProfileGrid software is free and available from http://www.ProfileGrid.org.

  10. Abnormal arrangement of a collagen/apatite extracellular matrix orthogonal to osteoblast alignment is constructed by a nanoscale periodic surface structure.

    PubMed

    Matsugaki, Aira; Aramoto, Gento; Ninomiya, Takafumi; Sawada, Hiroshi; Hata, Satoshi; Nakano, Takayoshi

    2015-01-01

    Morphological and directional alteration of cells is essential for structurally appropriate construction of tissues and organs. In particular, osteoblast alignment is crucial for the realization of anisotropic bone tissue microstructure. In this article, the orientation of a collagen/apatite extracellular matrix (ECM) was established by controlling osteoblast alignment using a surface geometry with nanometer-sized periodicity induced by laser ablation. Laser irradiation induced self-organized periodic structures (laser-induced periodic surface structures; LIPSS) with a spatial period equal to the wavelength of the incident laser on the surface of biomedical alloys of Ti-6Al-4V and Co-Cr-Mo. Osteoblast orientation was successfully induced parallel to the grating structure. Notably, both the fibrous orientation of the secreted collagen matrix and the c-axis of the produced apatite crystals were orientated orthogonal to the cell direction. To the best of our knowledge, this is the first report demonstrating that bone tissue anisotropy is controllable, including the characteristic organization of a collagen/apatite composite orthogonal to the osteoblast orientation, by controlling the cell alignment using periodic surface geometry. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Acute and Reproductive Effects of Align®, an Insecticide Containing Azadirachtin, on the Grape Berry Moth, Lobesia botrana

    PubMed Central

    Irigaray, F. Javier Sáenz-De-Cabezón; Moreno-Grijalba, Fernando; Marco, Vicente; Pérez-Moreno, Ignacio

    2010-01-01

    Azadirachtin, derived from the neem tree, Azadirachta indica A. Juss (Sapindales: Meliaceae), seems promising for use in integrated pest management programs to control a variety of pest species. A commercial formulation of azadirachtin, Align®, has been evaluated against different developmental stages of the European grape berry moth, Lobesia botrana Denis and Schiffermüller (Lepidoptera: Tortricidae). When administered orally, Align reduced the fecundity and fertility of adults treated with 1, 5, and 10 mg litre-1. At the highest doses, fecundity and fertility were zero, but longevity was not affected. An LC50 of 231.5 mg litre-1 was obtained when Align was sprayed on eggs less than 1 day old. Hatching of all egg classes was significantly reduced, and this reduction was more pronounced for eggs less than 24 h old. LC50 values of 2.1 mg litre-1 for first instars and 18.7 mg litre-1 for third instars were obtained when Align was present in the diet. Larvae reared on a diet containing different concentrations of Align did not molt into adults at the highest concentrations (0.3, 0.6, 1.2), and 50% molted at the lowest concentration (0.15). Phenotypic effects included inability to molt properly and deformities. The combination of acute toxicity and low, effective concentrations of Align observed in this study could lead to the inclusion of insecticides containing azadirachtin in integrated management programs against this pest. PMID:20578954

  12. Acute and reproductive effects of Align, an insecticide containing azadirachtin, on the grape berry moth, Lobesia botrana.

    PubMed

    Irigaray, F Javier Sáenz-De-Cabezón; Moreno-Grijalba, Fernando; Marco, Vicente; Pérez-Moreno, Ignacio

    2010-01-01

    Azadirachtin, derived from the neem tree, Azadirachta indica A. Juss (Sapindales: Meliaceae), seems promising for use in integrated pest management programs to control a variety of pest species. A commercial formulation of azadirachtin, Align, has been evaluated against different developmental stages of the European grape berry moth, Lobesia botrana Denis and Schiffermüller (Lepidoptera: Tortricidae). When administered orally, Align reduced the fecundity and fertility of adults treated with 1, 5, and 10 mg litre(-1). At the highest doses, fecundity and fertility were zero, but longevity was not affected. An LC(50) of 231.5 mg litre(-1) was obtained when Align was sprayed on eggs less than 1 day old. Hatching of all egg classes was significantly reduced, and this reduction was more pronounced for eggs less than 24 h old. LC(50) values of 2.1 mg litre(-1) for first instars and 18.7 mg litre(-1) for third instars were obtained when Align was present in the diet. Larvae reared on a diet containing different concentrations of Align did not molt into adults at the highest concentrations (0.3, 0.6, 1.2), and 50% molted at the lowest concentration (0.15). Phenotypic effects included inability to molt properly and deformities. The combination of acute toxicity and low, effective concentrations of Align observed in this study could lead to the inclusion of insecticides containing azadirachtin in integrated management programs against this pest.

  13. Statistical discovery of site inter-dependencies in sub-molecular hierarchical protein structuring

    PubMed Central

    2012-01-01

    Background Much progress has been made in understanding the 3D structure of proteins using methods such as NMR and X-ray crystallography. The resulting 3D structures are extremely informative, but do not always reveal which sites and residues within the structure are of special importance. Recently, there are indications that multiple-residue, sub-domain structural relationships within the larger 3D consensus structure of a protein can be inferred from the analysis of the multiple sequence alignment data of a protein family. These intra-dependent clusters of associated sites are used to indicate hierarchical inter-residue relationships within the 3D structure. To reveal the patterns of associations among individual amino acids or sub-domain components within the structure, we apply a k-modes attribute (aligned site) clustering algorithm to the ubiquitin and transthyretin families in order to discover associations among groups of sites within the multiple sequence alignment. We then observe what these associations imply within the 3D structure of these two protein families. Results The k-modes site clustering algorithm we developed maximizes the intra-group interdependencies based on a normalized mutual information measure. The clusters formed correspond to sub-structural components or binding and interface locations. Applying this data-directed method to the ubiquitin and transthyretin protein family multiple sequence alignments as a test bed, we located numerous interesting associations of interdependent sites. These clusters were then arranged into cluster tree diagrams which revealed four structural sub-domains within the single domain structure of ubiquitin and a single large sub-domain within transthyretin associated with the interface among transthyretin monomers. In addition, several clusters of mutually interdependent sites were discovered for each protein family, each of which appear to play an important role in the molecular structure and/or function. Conclusions Our results demonstrate that the method we present here using a k-modes site clustering algorithm based on interdependency evaluation among sites obtained from a sequence alignment of homologous proteins can provide significant insights into the complex, hierarchical inter-residue structural relationships within the 3D structure of a protein family. PMID:22793672

  14. Statistical discovery of site inter-dependencies in sub-molecular hierarchical protein structuring.

    PubMed

    Durston, Kirk K; Chiu, David Ky; Wong, Andrew Kc; Li, Gary Cl

    2012-07-13

    Much progress has been made in understanding the 3D structure of proteins using methods such as NMR and X-ray crystallography. The resulting 3D structures are extremely informative, but do not always reveal which sites and residues within the structure are of special importance. Recently, there are indications that multiple-residue, sub-domain structural relationships within the larger 3D consensus structure of a protein can be inferred from the analysis of the multiple sequence alignment data of a protein family. These intra-dependent clusters of associated sites are used to indicate hierarchical inter-residue relationships within the 3D structure. To reveal the patterns of associations among individual amino acids or sub-domain components within the structure, we apply a k-modes attribute (aligned site) clustering algorithm to the ubiquitin and transthyretin families in order to discover associations among groups of sites within the multiple sequence alignment. We then observe what these associations imply within the 3D structure of these two protein families. The k-modes site clustering algorithm we developed maximizes the intra-group interdependencies based on a normalized mutual information measure. The clusters formed correspond to sub-structural components or binding and interface locations. Applying this data-directed method to the ubiquitin and transthyretin protein family multiple sequence alignments as a test bed, we located numerous interesting associations of interdependent sites. These clusters were then arranged into cluster tree diagrams which revealed four structural sub-domains within the single domain structure of ubiquitin and a single large sub-domain within transthyretin associated with the interface among transthyretin monomers. In addition, several clusters of mutually interdependent sites were discovered for each protein family, each of which appear to play an important role in the molecular structure and/or function. Our results demonstrate that the method we present here using a k-modes site clustering algorithm based on interdependency evaluation among sites obtained from a sequence alignment of homologous proteins can provide significant insights into the complex, hierarchical inter-residue structural relationships within the 3D structure of a protein family.

  15. Population health intervention research training: the value of public health internships and mentorship.

    PubMed

    Hamelin, Anne-Marie; Paradis, Gilles

    2018-01-01

    Better alignment between academia and public health practice and policies are critical to improve public health actions. Training of future researchers to address complex issues and to conduct transdisciplinary and collaborative research will help improve this alignment. In this paper, we describe the role of internship placements and mentorship for trainees' skills development in population health intervention research and the benefits of embedding research trainees within public health organizations. This qualitative descriptive study assessed the perceptions of the role and benefits of internships and mentorship for population health intervention research training among former doctoral and postdoctoral students, public health mentors, and senior public health managers who participated in the 4P Program, a research training program which bridges academic training and the public health system in Quebec, Canada. Two types of interviews were conducted: telephone semi-structured interviews by an external evaluator and face-to-face trainee "exit" interviews by the Program co-director. Semi-annual evaluation reports from each trainee were also reviewed. Qualitative data were subjected to a thematic analysis. Internships provided trainees with a working knowledge of the public health system and the context in which decisions and public health interventions are implemented. It was an opportunity for trainees to interact with knowledge-user partners and assess the gap between research and practice. Effective mentorship was key to help trainees interpret the public health reality and develop population health intervention research skills. Trainees learned to ask the "how" questions that are critical for in-depth understanding of complex interventions and the conditions under which they can be best implemented. Conditions of success of internships and mentorship for population health intervention research included the alignment of the interests between the trainee, the mentor and the public health organization, quality mentoring, and the acquisition of specific population health intervention skills, especially collaborative research skills. The findings suggest that public health internships and mentorship facilitate trainee engagement in applied public health research.

  16. Playable stories: Making programming and 3D role-playing game design personally and socially relevant

    NASA Astrophysics Data System (ADS)

    Ingram-Goble, Adam

    This is an exploratory design study of a novel system for learning programming and 3D role-playing game design as tools for social change. This study was conducted at two sites. Participants in the study were ages 9-14 and worked for up to 15 hours with the platform to learn how to program and design video games with personally or socially relevant narratives. This first study was successful in that students learned to program a narrative game, and they viewed the social problem framing for the practices as an interesting aspect of the experience. The second study provided illustrative examples of how providing less general structure up-front, afforded players the opportunity to produce the necessary structures as needed for their particular design, and therefore had a richer understanding of what those structures represented. This study demonstrates that not only were participants able to use computational thinking skills such as Boolean and conditional logic, planning, modeling, abstraction, and encapsulation, they were able to bridge these skills to social domains they cared about. In particular, participants created stories about socially relevant topics without to explicit pushes by the instructors. The findings also suggest that the rapid uptake, and successful creation of personally and socially relevant narratives may have been facilitated by close alignment between the conceptual tools represented in the platform, and the domain of 3D role-playing games.

  17. Poly(vinyl alcohol)/cellulose nanofibril hybrid aerogels with an aligned microtubular porous structure and their composites with polydimethylsiloxane

    Treesearch

    Tianliang Zhai; Qifeng Zheng; Zhiyong Cai; Lih-Sheng Turng; Hesheng Xia; Shaoqin Gong

    2015-01-01

    Superhydrophobic poly(vinyl alcohol) (PVA)/ cellulose nanofibril (CNF) aerogels with a unidirectionally aligned microtubular porous structure were prepared using a unidirectional freeze-drying process, followed by the thermal chemical vapor deposition of methyltrichlorosilane. The silanized aerogels were characterized using various techniques including scanning...

  18. Transformation Education: A Vehicle for Structuring Group Care Organizations to Increase Service Quality and Effectiveness

    ERIC Educational Resources Information Center

    Ross, Andrew L.

    2007-01-01

    Transformation Education, an organizational philosophy and operating system, is designed to increase service quality and effectiveness of group care through aligning its organizational structure with its purpose. This alignment is achieved through creating a culture designed to dispense transformation rather than treatment. The author presents how…

  19. Prediction of β-turns in proteins from multiple alignment using neural network

    PubMed Central

    Kaur, Harpreet; Raghava, Gajendra Pal Singh

    2003-01-01

    A neural network-based method has been developed for the prediction of β-turns in proteins by using multiple sequence alignment. Two feed-forward back-propagation networks with a single hidden layer are used where the first-sequence structure network is trained with the multiple sequence alignment in the form of PSI-BLAST–generated position-specific scoring matrices. The initial predictions from the first network and PSIPRED-predicted secondary structure are used as input to the second structure-structure network to refine the predictions obtained from the first net. A significant improvement in prediction accuracy has been achieved by using evolutionary information contained in the multiple sequence alignment. The final network yields an overall prediction accuracy of 75.5% when tested by sevenfold cross-validation on a set of 426 nonhomologous protein chains. The corresponding Qpred, Qobs, and Matthews correlation coefficient values are 49.8%, 72.3%, and 0.43, respectively, and are the best among all the previously published β-turn prediction methods. The Web server BetaTPred2 (http://www.imtech.res.in/raghava/betatpred2/) has been developed based on this approach. PMID:12592033

  20. Mother and Home Visitor Emotional Well-Being and Alignment on Goals for Home Visiting as Factors for Program Engagement.

    PubMed

    Burrell, L; Crowne, S; Ojo, K; Snead, R; O'Neill, K; Cluxton-Keller, F; Duggan, A

    2018-05-31

    Objectives Family engagement in home visiting (HV), as indicated by length of enrollment, is a major challenge as most families do not stay enrolled for the intended duration prescribed by HV models. This study examined maternal and visitor emotional well-being as factors for maternal satisfaction with the program in addressing reasons for enrolling in HV and program engagement and the role of their working alliance with the visitor as a mediator of this. Methods Longitudinal data were collected from 148 mothers and 54 visitors in 21 HV programs. Mothers completed surveys shortly after enrolling and 6 months later to assess attributes of the working alliance with their visitor. Visitors completed a survey to assess work-related well-being. HV program data were used to measure engagement. Results Mothers enrolled for multiple, diverse reasons, most often to promote child development and parenting (96%). Mothers' satisfaction with program efforts to address reasons for enrollment was highest for parenting (79%) and lowest for jobs and education (30%). Results of the mediational path model indicated that ratings of the visitor on goal alignment were positively associated with engagement. Maternal emotional availability and visitor work-related emotional exhaustion were negatively associated with engagement. Exploratory analyses suggested that ratings of the visitor on goal alignment were a stronger predictor of engagement for mothers with low emotional availability compared to other mothers. Conclusions for Practice Visitor alignment with mothers on goals and responsiveness to reasons for enrolling appear to be effective in promoting engagement. Individualizing services to reflect maternal goals and emotional capacity may be important strategies to address engagement challenges.

  1. Biclustering as a method for RNA local multiple sequence alignment.

    PubMed

    Wang, Shu; Gutell, Robin R; Miranker, Daniel P

    2007-12-15

    Biclustering is a clustering method that simultaneously clusters both the domain and range of a relation. A challenge in multiple sequence alignment (MSA) is that the alignment of sequences is often intended to reveal groups of conserved functional subsequences. Simultaneously, the grouping of the sequences can impact the alignment; precisely the kind of dual situation biclustering is intended to address. We define a representation of the MSA problem enabling the application of biclustering algorithms. We develop a computer program for local MSA, BlockMSA, that combines biclustering with divide-and-conquer. BlockMSA simultaneously finds groups of similar sequences and locally aligns subsequences within them. Further alignment is accomplished by dividing both the set of sequences and their contents. The net result is both a multiple sequence alignment and a hierarchical clustering of the sequences. BlockMSA was tested on the subsets of the BRAliBase 2.1 benchmark suite that display high variability and on an extension to that suite to larger problem sizes. Also, alignments were evaluated of two large datasets of current biological interest, T box sequences and Group IC1 Introns. The results were compared with alignments computed by ClustalW, MAFFT, MUCLE and PROBCONS alignment programs using Sum of Pairs (SPS) and Consensus Count. Results for the benchmark suite are sensitive to problem size. On problems of 15 or greater sequences, BlockMSA is consistently the best. On none of the problems in the test suite are there appreciable differences in scores among BlockMSA, MAFFT and PROBCONS. On the T box sequences, BlockMSA does the most faithful job of reproducing known annotations. MAFFT and PROBCONS do not. On the Intron sequences, BlockMSA, MAFFT and MUSCLE are comparable at identifying conserved regions. BlockMSA is implemented in Java. Source code and supplementary datasets are available at http://aug.csres.utexas.edu/msa/

  2. Seismic anisotropy in the Earth's innermost inner core: Testing structural models against mineral physics predictions

    DOE PAGES

    Romanowicz, Barbara; Cao, Aimin; Godwal, Budhiram; ...

    2016-01-06

    Using an updated data set of ballistic PKIKP travel time data at antipodal distances, we test different models of anisotropy in the Earth's innermost inner core (IMIC) and obtain significantly better fits for a fast axis aligned with Earth's rotation axis, rather than a quasi-equatorial direction, as proposed recently. Reviewing recent results on the single crystal structure and elasticity of iron at core conditions, we find that an hcp structure with the fast c axis parallel to Earth's rotation is more likely but a body-centered cubic structure with the [111] axis aligned in that direction results in very similar predictionsmore » for seismic anisotropy. These models are therefore not distinguishable based on current seismological data. In addition, to match the seismological observations, the inferred strength of anisotropy in the IMIC (6–7%) implies almost perfect alignment of iron crystals, an intriguing, albeit unlikely situation, especially in the presence of heterogeneity, which calls for further studies. Fast axis of anisotropy in the central part of the inner core aligned with Earth's axis of rotation Lastly, the structure of iron in the inner core is most likely hcp, not bcc Not currently possible to distinguish between hcp and bcc structures from seismic observations« less

  3. Protein local structure alignment under the discrete Fréchet distance.

    PubMed

    Zhu, Binhai

    2007-12-01

    Protein structure alignment is a fundamental problem in computational and structural biology. While there has been lots of experimental/heuristic methods and empirical results, very few results are known regarding the algorithmic/complexity aspects of the problem, especially on protein local structure alignment. A well-known measure to characterize the similarity of two polygonal chains is the famous Fréchet distance, and with the application of protein-related research, a related discrete Fréchet distance has been used recently. In this paper, following the recent work of Jiang et al. we investigate the protein local structural alignment problem using bounded discrete Fréchet distance. Given m proteins (or protein backbones, which are 3D polygonal chains), each of length O(n), our main results are summarized as follows: * If the number of proteins, m, is not part of the input, then the problem is NP-complete; moreover, under bounded discrete Fréchet distance it is NP-hard to approximate the maximum size common local structure within a factor of n(1-epsilon). These results hold both when all the proteins are static and when translation/rotation are allowed. * If the number of proteins, m, is a constant, then there is a polynomial time solution for the problem.

  4. GeneSilico protein structure prediction meta-server.

    PubMed

    Kurowski, Michal A; Bujnicki, Janusz M

    2003-07-01

    Rigorous assessments of protein structure prediction have demonstrated that fold recognition methods can identify remote similarities between proteins when standard sequence search methods fail. It has been shown that the accuracy of predictions is improved when refined multiple sequence alignments are used instead of single sequences and if different methods are combined to generate a consensus model. There are several meta-servers available that integrate protein structure predictions performed by various methods, but they do not allow for submission of user-defined multiple sequence alignments and they seldom offer confidentiality of the results. We developed a novel WWW gateway for protein structure prediction, which combines the useful features of other meta-servers available, but with much greater flexibility of the input. The user may submit an amino acid sequence or a multiple sequence alignment to a set of methods for primary, secondary and tertiary structure prediction. Fold-recognition results (target-template alignments) are converted into full-atom 3D models and the quality of these models is uniformly assessed. A consensus between different FR methods is also inferred. The results are conveniently presented on-line on a single web page over a secure, password-protected connection. The GeneSilico protein structure prediction meta-server is freely available for academic users at http://genesilico.pl/meta.

  5. GeneSilico protein structure prediction meta-server

    PubMed Central

    Kurowski, Michal A.; Bujnicki, Janusz M.

    2003-01-01

    Rigorous assessments of protein structure prediction have demonstrated that fold recognition methods can identify remote similarities between proteins when standard sequence search methods fail. It has been shown that the accuracy of predictions is improved when refined multiple sequence alignments are used instead of single sequences and if different methods are combined to generate a consensus model. There are several meta-servers available that integrate protein structure predictions performed by various methods, but they do not allow for submission of user-defined multiple sequence alignments and they seldom offer confidentiality of the results. We developed a novel WWW gateway for protein structure prediction, which combines the useful features of other meta-servers available, but with much greater flexibility of the input. The user may submit an amino acid sequence or a multiple sequence alignment to a set of methods for primary, secondary and tertiary structure prediction. Fold-recognition results (target-template alignments) are converted into full-atom 3D models and the quality of these models is uniformly assessed. A consensus between different FR methods is also inferred. The results are conveniently presented on-line on a single web page over a secure, password-protected connection. The GeneSilico protein structure prediction meta-server is freely available for academic users at http://genesilico.pl/meta. PMID:12824313

  6. Interspecific variation in mitochondrial serine transfer RNA (UCN) in Euptychiina butterflies (Lepidoptera: Satyrinae): structure and alignment.

    PubMed

    Marín, Mario Alejandro; López, Andrés; Uribe, Sandra Inés

    2012-06-01

    The nucleotide variation and structural patterns of mitochondrial RNA molecule have been proposed as useful tools in molecular systematics; however, their usefulness is always subject to a proper assessment of homology in the sequence alignment. The present study describes the secondary structure of mitochondrial tRNA for the amino acid serine (UCN) on 13 Euptychiina species and the evaluation of its potential use for evolutionary studies in this group of butterflies. The secondary structure of tRNAs showed variation among the included species except between Hermeuptychia sp1 and sp2. Variation was concentrated in the ribotimidina-pseudouridine-cystosine (TψC), dihydrouridine (DHU) and variable loops and in the DHU and TψC arms. These results suggest this region as a potential marker useful for taxonomic differentiation of species in this group and also confirm the importance of including information from the secondary structure of tRNA to optimize the alignments.

  7. Constant field gradient planar coupled cavity structure

    DOEpatents

    Kang, Y.W.; Kustom, R.L.

    1999-07-27

    A cavity structure is disclosed having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam. 16 figs.

  8. Constant field gradient planar coupled cavity structure

    DOEpatents

    Kang, Yoon W.; Kustom, Robert L.

    1999-01-01

    A cavity structure having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam.

  9. A novel bioreactor for the generation of highly aligned 3D skeletal muscle-like constructs through orientation of fibrin via application of static strain.

    PubMed

    Heher, Philipp; Maleiner, Babette; Prüller, Johanna; Teuschl, Andreas Herbert; Kollmitzer, Josef; Monforte, Xavier; Wolbank, Susanne; Redl, Heinz; Rünzler, Dominik; Fuchs, Christiane

    2015-09-01

    The generation of functional biomimetic skeletal muscle constructs is still one of the fundamental challenges in skeletal muscle tissue engineering. With the notion that structure strongly dictates functional capabilities, a myriad of cell types, scaffold materials and stimulation strategies have been combined. To further optimize muscle engineered constructs, we have developed a novel bioreactor system (MagneTissue) for rapid engineering of skeletal muscle-like constructs with the aim to resemble native muscle in terms of structure, gene expression profile and maturity. Myoblasts embedded in fibrin, a natural hydrogel that serves as extracellular matrix, are subjected to mechanical stimulation via magnetic force transmission. We identify static mechanical strain as a trigger for cellular alignment concomitant with the orientation of the scaffold into highly organized fibrin fibrils. This ultimately yields myotubes with a more mature phenotype in terms of sarcomeric patterning, diameter and length. On the molecular level, a faster progression of the myogenic gene expression program is evident as myogenic determination markers MyoD and Myogenin as well as the Ca(2+) dependent contractile structural marker TnnT1 are significantly upregulated when strain is applied. The major advantage of the MagneTissue bioreactor system is that the generated tension is not exclusively relying on the strain generated by the cells themselves in response to scaffold anchoring but its ability to subject the constructs to individually adjustable strain protocols. In future work, this will allow applying mechanical stimulation with different strain regimes in the maturation process of tissue engineered constructs and elucidating the role of mechanotransduction in myogenesis. Mechanical stimulation of tissue engineered skeletal muscle constructs is a promising approach to increase tissue functionality. We have developed a novel bioreactor-based 3D culture system, giving the user the possibility to apply different strain regimes like static, cyclic or ramp strain to myogenic precursor cells embedded in a fibrin scaffold. Application of static mechanical strain leads to alignment of fibrin fibrils along the axis of strain and concomitantly to highly aligned myotube formation. Additionally, the pattern of myogenic gene expression follows the temporal progression observed in vivo with a more thorough induction of the myogenic program when static strain is applied. Ultimately, the strain protocol used in this study results in a higher degree of muscle maturity demonstrated by enhanced sarcomeric patterning and increased myotube diameter and length. The introduced bioreactor system enables new possibilities in muscle tissue engineering as longer cultivation periods and different strain applications will yield tissue engineered muscle-like constructs with improved characteristics in regard to functionality and biomimicry. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  10. FASMA: a service to format and analyze sequences in multiple alignments.

    PubMed

    Costantini, Susan; Colonna, Giovanni; Facchiano, Angelo M

    2007-12-01

    Multiple sequence alignments are successfully applied in many studies for under- standing the structural and functional relations among single nucleic acids and protein sequences as well as whole families. Because of the rapid growth of sequence databases, multiple sequence alignments can often be very large and difficult to visualize and analyze. We offer a new service aimed to visualize and analyze the multiple alignments obtained with different external algorithms, with new features useful for the comparison of the aligned sequences as well as for the creation of a final image of the alignment. The service is named FASMA and is available at http://bioinformatica.isa.cnr.it/FASMA/.

  11. iPARTS2: an improved tool for pairwise alignment of RNA tertiary structures, version 2.

    PubMed

    Yang, Chung-Han; Shih, Cheng-Ting; Chen, Kun-Tze; Lee, Po-Han; Tsai, Ping-Han; Lin, Jian-Cheng; Yen, Ching-Yu; Lin, Tiao-Yin; Lu, Chin Lung

    2016-07-08

    Since its first release in 2010, iPARTS has become a valuable tool for globally or locally aligning two RNA 3D structures. It was implemented by a structural alphabet (SA)-based approach, which uses an SA of 23 letters to reduce RNA 3D structures into 1D sequences of SA letters and applies traditional sequence alignment to these SA-encoded sequences for determining their global or local similarity. In this version, we have re-implemented iPARTS into a new web server iPARTS2 by constructing a totally new SA, which consists of 92 elements with each carrying both information of base and backbone geometry for a representative nucleotide. This SA is significantly different from the one used in iPARTS, because the latter consists of only 23 elements with each carrying only the backbone geometry information of a representative nucleotide. Our experimental results have shown that iPARTS2 outperforms its previous version iPARTS and also achieves better accuracy than other popular tools, such as SARA, SETTER and RASS, in RNA alignment quality and function prediction. iPARTS2 takes as input two RNA 3D structures in the PDB format and outputs their global or local alignments with graphical display. iPARTS2 is now available online at http://genome.cs.nthu.edu.tw/iPARTS2/. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  12. Making Macroscopic Assemblies of Aligned Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Smalley, Richard E.; Colbert, Daniel T.; Smith, Ken A.; Walters, Deron A.; Casavant, Michael J.; Qin, Xiaochuan; Yakobson, Boris; Hauge, Robert H.; Saini, Rajesh Kumar; Chiung, Wan-Ting; hide

    2005-01-01

    A method of aligning and assembling single-wall carbon nanotubes (SWNTs) to fabricate macroscopic structures has been invented. The method entails suspending SWNTs in a fluid, orienting the SWNTs by use of a magnetic and/or electric field, and then removing the aligned SWNTs from suspension in such a way as to assemble them while maintaining the alignment. SWNTs are essentially tubular extensions of fullerene molecules. It is desirable to assemble aligned SWNTs into macroscopic structures because the common alignment of the SWNTs in such a structure makes it possible to exploit, on a macroscopic scale, the unique mechanical, chemical, and electrical properties that individual oriented SWNTs exhibit at the molecular level. Because of their small size and high electrical conductivity, carbon nanotubes, and especially SWNTs, are useful for making electrical connectors in integrated circuits. Carbon nanotubes can be used as antennas at optical frequencies, and as probes in scanning tunneling microscopes, atomic-force microscopes, and the like. Carbon nanotubes can be used with or instead of carbon black in tires. Carbon nanotubes are useful as supports for catalysts. Ropes of SWNTs are metallic and, as such, are potentially useful in some applications in which electrical conductors are needed - for example, they could be used as additives in formulating electrically conductive paints. Finally, macroscopic assemblies of aligned SWNTs can serve as templates for the growth of more and larger structures of the same type. The great variety of tubular fullerene molecules and of the structures that could be formed by assembling them in various ways precludes a complete description of the present method within the limits of this article. It must suffice to present a typical example of the use of one of many possible variants of the method to form a membrane comprising SWNTs aligned substantially parallel to each other in the membrane plane. The apparatus used in this variant of the method (see figure) includes a reservoir containing SWNTs dispersed in a suspending agent (for example, dimethylformamide) and a reservoir containing a suitable solvent (for example, water mixed with a surfactant). By use of either pressurized gas supplied from upstream or suction from downstream, the suspension of SWNTs and the solvent are forced to mix and flow into a tank. A filter inside the tank contains pores small enough to prevent the passage of most SWNTs, but large enough to allow the passage of molecules of the solvent and suspending agent. The filter is oriented perpendicular to the flow path. A magnetic field parallel to the plane of the filter is applied. The success of the method is based on the tendency of SWNTs to become aligned with their longitudinal axes parallel to an applied magnetic field. The alignment energy of an SWNT increases with the length of the SWNT and the magnetic-field strength. In order to obtain an acceptably small degree of statistical deviation of SWNTs of a given length from alignment with a magnetic field, one must make the field strong enough so that the thermal energy associated with rotation of an SWNT away from alignment is less than the alignment energy.

  13. DNATagger, colors for codons.

    PubMed

    Scherer, N M; Basso, D M

    2008-09-16

    DNATagger is a web-based tool for coloring and editing DNA, RNA and protein sequences and alignments. It is dedicated to the visualization of protein coding sequences and also protein sequence alignments to facilitate the comprehension of evolutionary processes in sequence analysis. The distinctive feature of DNATagger is the use of codons as informative units for coloring DNA and RNA sequences. The codons are colored according to their corresponding amino acids. It is the first program that colors codons in DNA sequences without being affected by "out-of-frame" gaps of alignments. It can handle single gaps and gaps inside the triplets. The program also provides the possibility to edit the alignments and change color patterns and translation tables. DNATagger is a JavaScript application, following the W3C guidelines, designed to work on standards-compliant web browsers. It therefore requires no installation and is platform independent. The web-based DNATagger is available as free and open source software at http://www.inf.ufrgs.br/~dmbasso/dnatagger/.

  14. Optical tools and techniques for aligning solar payloads with the SPARCS control system. [Solar Pointing Aerobee Rocket Control System

    NASA Technical Reports Server (NTRS)

    Thomas, N. L.; Chisel, D. M.

    1976-01-01

    The success of a rocket-borne experiment depends not only on the pointing of the attitude control system, but on the alignment of the attitude control system to the payload. To ensure proper alignment, special optical tools and alignment techniques are required. Those that were used in the SPARCS program are described and discussed herein. These tools include theodolites, autocollimators, a 38-cm diameter solar simulator, a high-performance 1-m heliostat to provide a stable solar source during the integration of the rocket payload, a portable 75-cm sun tracker for use at the launch site, and an innovation called the Solar Alignment Prism. Using the real sun as the primary reference under field conditions, the Solar Alignment Prism facilitates the coalignment of the attitude sun sensor with the payload. The alignment techniques were developed to ensure the precise alignment of the solar payloads to the SPARCS attitude sensors during payload integration and to verify the required alignment under field conditions just prior to launch.

  15. JVM: Java Visual Mapping tool for next generation sequencing read.

    PubMed

    Yang, Ye; Liu, Juan

    2015-01-01

    We developed a program JVM (Java Visual Mapping) for mapping next generation sequencing read to reference sequence. The program is implemented in Java and is designed to deal with millions of short read generated by sequence alignment using the Illumina sequencing technology. It employs seed index strategy and octal encoding operations for sequence alignments. JVM is useful for DNA-Seq, RNA-Seq when dealing with single-end resequencing. JVM is a desktop application, which supports reads capacity from 1 MB to 10 GB.

  16. Design and fabrication of advanced fiber alignment structures for field-installable fiber connectors

    NASA Astrophysics Data System (ADS)

    Van Erps, Jürgen; Vervaeke, Michael; Sánchez Martínez, Alberto; Beri, Stefano; Debaes, Christof; Watté, Jan; Thienpont, Hugo

    2012-06-01

    Fiber-To-The-Home (FTTH) networks have been adopted as a potential replacement of traditional electrical connections for the 'last mile' transmission of information at bandwidths over 1Gb/s. However, the success and adoption of optical access networks critically depend on the quality and reliability of connections between optical fibers. In particular a further reduction of insertion loss of field-installable connectors must be achieved without a significant increase in component cost. This requires precise alignment of fibers that can differ in terms of ellipticity, eccentricity or diameter and seems hardly achievable using today's widespread ferrule-based alignment systems. Novel low-cost structures for bare fiber alignment with outstanding positioning accuracies are strongly desired as they would allow reducing loss beyond the level achievable with ferrule-bore systems. However, the realization of such alignment system is challenging as it should provide sufficient force to position the fiber with sub-micron accuracy required in positioning the fiber. In this contribution we propose, design and prototype a bare-fiber alignment system which makes use of deflectable/compressible micro-cantilevers. Such cantilevers behave as springs and provide self-centering functionality to the structure. Simulations of the mechanical properties of the cantilevers are carried out in order to get an analytical approximation and a mathematical model of the spring constant and stress in the structure. Elastic constants of the order of 104 to 105N/m are found out to be compatible with a proof stress of 70 MPa. Finally a first self-centering structure is prototyped in PMMA using our Deep Proton Writing technology. The spring constants of the fabricated cantilevers are in the range of 4 to 6 × 104N/m and the stress is in the range 10 to 20 MPa. These self-centering structures have the potential to become the basic building blocks for a new generation of field-installable connectors.

  17. Communication: Gas-phase structural isomer identification by Coulomb explosion of aligned molecules

    NASA Astrophysics Data System (ADS)

    Burt, Michael; Amini, Kasra; Lee, Jason W. L.; Christiansen, Lars; Johansen, Rasmus R.; Kobayashi, Yuki; Pickering, James D.; Vallance, Claire; Brouard, Mark; Stapelfeldt, Henrik

    2018-03-01

    The gas-phase structures of four difluoroiodobenzene and two dihydroxybromobenzene isomers were identified by correlating the emission angles of atomic fragment ions created, following femtosecond laser-induced Coulomb explosion. The structural determinations were facilitated by confining the most polarizable axis of each molecule to the detection plane prior to the Coulomb explosion event using one-dimensional laser-induced adiabatic alignment. For a molecular target consisting of two difluoroiodobenzene isomers, each constituent structure could additionally be singled out and distinguished.

  18. Health System Creation and Integration at a Health Sciences University: A Five-Year Follow-up.

    PubMed

    Slade, Catherine P; Azziz, Ricardo; Levin, Steven; Caughman, Gretchen B; Hefner, David S; Halbur, Kimberly V; Tingen, Martha S; James, Susan

    Shifting healthcare market forces and regulation have exerted near-constant pressure on U.S. academic health centers (AHCs) attempting to successfully execute their traditional tripartite mission. A governance structure and organizational alignment that works well under one set of conditions is rarely optimal when conditions change. Thus, the degree and type of alignment of an AHC's clinical, educational, and faculty practice organizations have changed regularly within the sector, typically landing near one end or the other on a continuum from fully aligned with centralized governance to largely independent with separate governance. The authors examine the case of Georgia Regents University and Health System in this context. In step with industry trends, the institution's governance structure swung from fully aligned/centralized governance in the early 1990s to essentially separate and decentralized by 2000. In 2010, the Georgia Regents University organizations achieved rapid realignment by creating a governance structure of sufficient strength and flexibility to absorb and adjust to continuing external upheaval. The hospitals, clinics, and physician-faculty practice group were combined into one integrated health system, then aligned with the university to form the state's only public AHC under aligned, but distinct, corporate and management structures. The years since reorganization have seen significant growth in patient volumes and complexity, improved service quality, and enhanced faculty physician satisfaction, while also significantly increasing economic contributions from the health system to the academic mission. This case study offers observations and lessons learned that may be useful to other higher education institutions considering reorganization.

  19. Incremental Ontology-Based Extraction and Alignment in Semi-structured Documents

    NASA Astrophysics Data System (ADS)

    Thiam, Mouhamadou; Bennacer, Nacéra; Pernelle, Nathalie; Lô, Moussa

    SHIRIis an ontology-based system for integration of semi-structured documents related to a specific domain. The system’s purpose is to allow users to access to relevant parts of documents as answers to their queries. SHIRI uses RDF/OWL for representation of resources and SPARQL for their querying. It relies on an automatic, unsupervised and ontology-driven approach for extraction, alignment and semantic annotation of tagged elements of documents. In this paper, we focus on the Extract-Align algorithm which exploits a set of named entity and term patterns to extract term candidates to be aligned with the ontology. It proceeds in an incremental manner in order to populate the ontology with terms describing instances of the domain and to reduce the access to extern resources such as Web. We experiment it on a HTML corpus related to call for papers in computer science and the results that we obtain are very promising. These results show how the incremental behaviour of Extract-Align algorithm enriches the ontology and the number of terms (or named entities) aligned directly with the ontology increases.

  20. Optical Testing and Verification Methods for the James Webb Space Telescope Integrated Science Instrument Module Element

    NASA Technical Reports Server (NTRS)

    Antonille, Scott R.; Miskey, Cherie L.; Ohl, Raymond G.; Rohrbach, Scott O.; Aronstein, David L.; Bartoszyk, Andrew E.; Bowers, Charles W.; Cofie, Emmanuel; Collins, Nicholas R.; Comber, Brian J.; hide

    2016-01-01

    NASA's James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (40K). The JWST Observatory includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM) that contains four science instruments (SI) and the fine guider. The SIs are mounted to a composite metering structure. The SI and guider units were integrated to the ISIM structure and optically tested at the NASA Goddard Space Flight Center as a suite using the Optical Telescope Element SIMulator (OSIM). OSIM is a full field, cryogenic JWST telescope simulator. SI performance, including alignment and wave front error, were evaluated using OSIM. We describe test and analysis methods for optical performance verification of the ISIM Element, with an emphasis on the processes used to plan and execute the test. The complexity of ISIM and OSIM drove us to develop a software tool for test planning that allows for configuration control of observations, associated scripts, and management of hardware and software limits and constraints, as well as tools for rapid data evaluation, and flexible re-planning in response to the unexpected. As examples of our test and analysis approach, we discuss how factors such as the ground test thermal environment are compensated in alignment. We describe how these innovative methods for test planning and execution and post-test analysis were instrumental in the verification program for the ISIM element, with enough information to allow the reader to consider these innovations and lessons learned in this successful effort in their future testing for other programs.

  1. Optical testing and verification methods for the James Webb Space Telescope Integrated Science Instrument Module element

    NASA Astrophysics Data System (ADS)

    Antonille, Scott R.; Miskey, Cherie L.; Ohl, Raymond G.; Rohrbach, Scott O.; Aronstein, David L.; Bartoszyk, Andrew E.; Bowers, Charles W.; Cofie, Emmanuel; Collins, Nicholas R.; Comber, Brian J.; Eichhorn, William L.; Glasse, Alistair C.; Gracey, Renee; Hartig, George F.; Howard, Joseph M.; Kelly, Douglas M.; Kimble, Randy A.; Kirk, Jeffrey R.; Kubalak, David A.; Landsman, Wayne B.; Lindler, Don J.; Malumuth, Eliot M.; Maszkiewicz, Michael; Rieke, Marcia J.; Rowlands, Neil; Sabatke, Derek S.; Smith, Corbett T.; Smith, J. Scott; Sullivan, Joseph F.; Telfer, Randal C.; Te Plate, Maurice; Vila, M. Begoña.; Warner, Gerry D.; Wright, David; Wright, Raymond H.; Zhou, Julia; Zielinski, Thomas P.

    2016-09-01

    NASA's James Webb Space Telescope (JWST) is a 6.5m diameter, segmented, deployable telescope for cryogenic IR space astronomy. The JWST Observatory includes the Optical Telescope Element (OTE) and the Integrated Science Instrument Module (ISIM), that contains four science instruments (SI) and the Fine Guidance Sensor (FGS). The SIs are mounted to a composite metering structure. The SIs and FGS were integrated to the ISIM structure and optically tested at NASA's Goddard Space Flight Center using the Optical Telescope Element SIMulator (OSIM). OSIM is a full-field, cryogenic JWST telescope simulator. SI performance, including alignment and wavefront error, was evaluated using OSIM. We describe test and analysis methods for optical performance verification of the ISIM Element, with an emphasis on the processes used to plan and execute the test. The complexity of ISIM and OSIM drove us to develop a software tool for test planning that allows for configuration control of observations, implementation of associated scripts, and management of hardware and software limits and constraints, as well as tools for rapid data evaluation, and flexible re-planning in response to the unexpected. As examples of our test and analysis approach, we discuss how factors such as the ground test thermal environment are compensated in alignment. We describe how these innovative methods for test planning and execution and post-test analysis were instrumental in the verification program for the ISIM element, with enough information to allow the reader to consider these innovations and lessons learned in this successful effort in their future testing for other programs.

  2. Reverse freeze casting: a new method for fabricating highly porous titanium scaffolds with aligned large pores.

    PubMed

    Yook, Se-Won; Jung, Hyun-Do; Park, Chang-Hoon; Shin, Kwan-Ha; Koh, Young-Hag; Estrin, Yuri; Kim, Hyoun-Ee

    2012-07-01

    Highly porous titanium with aligned large pores up to 500 μm in size, which is suitable for scaffold applications, was successfully fabricated using the reverse freeze casting method. In this process we have newly developed, the Ti powders migrated spontaneously along the pre-aligned camphene boundaries at a temperature of 45.5°C and formed a titanium-camphene mixture with an aligned structure; this was followed by freeze drying and sintering. As the casting time increased from 24 to 48 h, the initial columnar structures turned into lamellar structures, with the porosity decreasing from 69 to 51%. This reduction in porosity caused the compressive yield strength to increase from 121 to 302 MPa, with an elastic modulus of the samples being in the range of 2-5 GPa. In addition, it was demonstrated that reverse freeze casting can also be successfully applied to various other raw powders, suggesting that the method developed in this work opens up new avenues for the production of a range of porous metallic and ceramic scaffolds with highly aligned pores. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. Energy level alignment at molecule-metal interfaces from an optimally tuned range-separated hybrid functional

    DOE PAGES

    Liu, Zhen-Fei; Egger, David A.; Refaely-Abramson, Sivan; ...

    2017-02-21

    The alignment of the frontier orbital energies of an adsorbed molecule with the substrate Fermi level at metal-organic interfaces is a fundamental observable of significant practical importance in nanoscience and beyond. Typical density functional theory calculations, especially those using local and semi-local functionals, often underestimate level alignment leading to inaccurate electronic structure and charge transport properties. Here, we develop a new fully self-consistent predictive scheme to accurately compute level alignment at certain classes of complex heterogeneous molecule-metal interfaces based on optimally tuned range-separated hybrid functionals. Starting from a highly accurate description of the gas-phase electronic structure, our method by constructionmore » captures important nonlocal surface polarization effects via tuning of the long-range screened exchange in a range-separated hybrid in a non-empirical and system-specific manner. We implement this functional in a plane-wave code and apply it to several physisorbed and chemisorbed molecule-metal interface systems. Our results are in quantitative agreement with experiments, the both the level alignment and work function changes. This approach constitutes a new practical scheme for accurate and efficient calculations of the electronic structure of molecule-metal interfaces.« less

  4. Energy level alignment at molecule-metal interfaces from an optimally tuned range-separated hybrid functional

    NASA Astrophysics Data System (ADS)

    Liu, Zhen-Fei; Egger, David A.; Refaely-Abramson, Sivan; Kronik, Leeor; Neaton, Jeffrey B.

    2017-03-01

    The alignment of the frontier orbital energies of an adsorbed molecule with the substrate Fermi level at metal-organic interfaces is a fundamental observable of significant practical importance in nanoscience and beyond. Typical density functional theory calculations, especially those using local and semi-local functionals, often underestimate level alignment leading to inaccurate electronic structure and charge transport properties. In this work, we develop a new fully self-consistent predictive scheme to accurately compute level alignment at certain classes of complex heterogeneous molecule-metal interfaces based on optimally tuned range-separated hybrid functionals. Starting from a highly accurate description of the gas-phase electronic structure, our method by construction captures important nonlocal surface polarization effects via tuning of the long-range screened exchange in a range-separated hybrid in a non-empirical and system-specific manner. We implement this functional in a plane-wave code and apply it to several physisorbed and chemisorbed molecule-metal interface systems. Our results are in quantitative agreement with experiments, the both the level alignment and work function changes. Our approach constitutes a new practical scheme for accurate and efficient calculations of the electronic structure of molecule-metal interfaces.

  5. Geometrical appearance and spatial arrangement of structural blocks of the Malan loess in NW China: implications for the formation of loess columns

    NASA Astrophysics Data System (ADS)

    Li, Yanrong; Zhang, Tao; Zhang, Yongbo; Xu, Qiang

    2018-06-01

    Loess, as one of the main Quaternary deposits, covers approximately 6% of the land surface of the Earth. Although loess is loose and fragile, loess columns are popular and they can stand stably for hundreds of years, thereby forming a spectacular landform. The formation of such special column-shaped soil structures is puzzling, and the underlying fundamentals remain unclear. The present study focuses on quantifying and examining the geometrical shape and spatial alignment of structural blocks of the Malan loess at different locations in the Loess Plateau of China. The structural blocks under investigation include clay- and silt-sized particles, aggregates, fragments, lumps, and columns, which vary in size from microns to tens of meters. Regardless of their size, the structural blocks of the Malan loess are found to be similar in shape, i.e., elongated with a length-to-width ratio of approximately 2.6. The aggregates, fragments, lumps, columns, and macropores between aggregates exhibit strong concentration in the vertical or subvertical alignment. These phenomena imply that the Malan loess is anisotropic and it is composed of a combination of vertically aligned strong units and vertically aligned weak segments. Based on this, "vertiloess" structure is proposed to denote this combination. The vertiloess structure prevents horizontal erosion, but favors spalling, peeling, toppling, falling and cracking-sliding of vertical loess pieces, thereby forming loess columns.

  6. Alignment hierarchies: engineering architecture from the nanometre to the micrometre scale.

    PubMed

    Kureshi, Alvena; Cheema, Umber; Alekseeva, Tijna; Cambrey, Alison; Brown, Robert

    2010-12-06

    Natural tissues are built of metabolites, soluble proteins and solid extracellular matrix components (largely fibrils) together with cells. These are configured in highly organized hierarchies of structure across length scales from nanometre to millimetre, with alignments that are dominated by anisotropies in their fibrillar matrix. If we are to successfully engineer tissues, these hierarchies need to be mimicked with an understanding of the interaction between them. In particular, the movement of different elements of the tissue (e.g. molecules, cells and bulk fluids) is controlled by matrix structures at distinct scales. We present three novel systems to introduce alignment of collagen fibrils, cells and growth factor gradients within a three-dimensional collagen scaffold using fluid flow, embossing and layering of construct. Importantly, these can be seen as different parts of the same hierarchy of three-dimensional structure, as they are all formed into dense collagen gels. Fluid flow aligns collagen fibrils at the nanoscale, embossed topographical features provide alignment cues at the microscale and introducing layered configuration to three-dimensional collagen scaffolds provides microscale- and mesoscale-aligned pathways for protein factor delivery as well as barriers to confine protein diffusion to specific spatial directions. These seemingly separate methods can be employed to increase complexity of simple extracellular matrix scaffolds, providing insight into new approaches to directly fabricate complex physical and chemical cues at different hierarchical scales, similar to those in natural tissues.

  7. Incorporating Health Education into Employee Assistance Programs.

    ERIC Educational Resources Information Center

    Miller, Richard E.

    1985-01-01

    Methods of aligning health education with the goals and functions of employee assistance programs are discussed. The role of the health educator in developing these programs is explained in a description of employee assistance program service standards and specific sub-tasks. (DF)

  8. Aligning Needs, Expectations, and Learning Outcomes to Sustain Self-Efficacy through Transfer Learning Community Programs

    ERIC Educational Resources Information Center

    Leptien, Jennifer R.

    2015-01-01

    This chapter addresses strengths and difficulties encountered in implementing transfer learning community models and how efficacy is supported through transfer learning community programming. Transfer programming best practices and recommendations for program improvements are presented.

  9. Towards Long-Range RNA Structure Prediction in Eukaryotic Genes.

    PubMed

    Pervouchine, Dmitri D

    2018-06-15

    The ability to form an intramolecular structure plays a fundamental role in eukaryotic RNA biogenesis. Proximate regions in the primary transcripts fold into a local secondary structure, which is then hierarchically assembled into a tertiary structure that is stabilized by RNA-binding proteins and long-range intramolecular base pairings. While the local RNA structure can be predicted reasonably well for short sequences, long-range structure at the scale of eukaryotic genes remains problematic from the computational standpoint. The aim of this review is to list functional examples of long-range RNA structures, to summarize current comparative methods of structure prediction, and to highlight their advances and limitations in the context of long-range RNA structures. Most comparative methods implement the “first-align-then-fold” principle, i.e., they operate on multiple sequence alignments, while functional RNA structures often reside in non-conserved parts of the primary transcripts. The opposite “first-fold-then-align” approach is currently explored to a much lesser extent. Developing novel methods in both directions will improve the performance of comparative RNA structure analysis and help discover novel long-range structures, their higher-order organization, and RNA⁻RNA interactions across the transcriptome.

  10. ElecSus: Extension to arbitrary geometry magneto-optics

    NASA Astrophysics Data System (ADS)

    Keaveney, James; Adams, Charles S.; Hughes, Ifan G.

    2018-03-01

    We present a major update to ElecSus, a computer program and underlying model to calculate the electric susceptibility of an alkali-metal atomic vapour. Knowledge of the electric susceptibility of a medium is essential to predict its absorptive and dispersive properties. In this version we implement several changes which significantly extend the range of applications of ElecSus, the most important of which is support for non-axial magnetic fields (i.e. fields which are not aligned with the light propagation axis). Supporting this change requires a much more general approach to light propagation in the system, which we have now implemented. We exemplify many of these new applications by comparing ElecSus to experimental data. In addition, we have developed a graphical user interface front-end which makes the program much more accessible, and have improved on several other minor areas of the program structure.

  11. Structural alignment of protein descriptors - a combinatorial model.

    PubMed

    Antczak, Maciej; Kasprzak, Marta; Lukasiak, Piotr; Blazewicz, Jacek

    2016-09-17

    Structural alignment of proteins is one of the most challenging problems in molecular biology. The tertiary structure of a protein strictly correlates with its function and computationally predicted structures are nowadays a main premise for understanding the latter. However, computationally derived 3D models often exhibit deviations from the native structure. A way to confirm a model is a comparison with other structures. The structural alignment of a pair of proteins can be defined with the use of a concept of protein descriptors. The protein descriptors are local substructures of protein molecules, which allow us to divide the original problem into a set of subproblems and, consequently, to propose a more efficient algorithmic solution. In the literature, one can find many applications of the descriptors concept that prove its usefulness for insight into protein 3D structures, but the proposed approaches are presented rather from the biological perspective than from the computational or algorithmic point of view. Efficient algorithms for identification and structural comparison of descriptors can become crucial components of methods for structural quality assessment as well as tertiary structure prediction. In this paper, we propose a new combinatorial model and new polynomial-time algorithms for the structural alignment of descriptors. The model is based on the maximum-size assignment problem, which we define here and prove that it can be solved in polynomial time. We demonstrate suitability of this approach by comparison with an exact backtracking algorithm. Besides a simplification coming from the combinatorial modeling, both on the conceptual and complexity level, we gain with this approach high quality of obtained results, in terms of 3D alignment accuracy and processing efficiency. All the proposed algorithms were developed and integrated in a computationally efficient tool descs-standalone, which allows the user to identify and structurally compare descriptors of biological molecules, such as proteins and RNAs. Both PDB (Protein Data Bank) and mmCIF (macromolecular Crystallographic Information File) formats are supported. The proposed tool is available as an open source project stored on GitHub ( https://github.com/mantczak/descs-standalone ).

  12. Prevalence, effectiveness, and characteristics of pharmacy-based medication synchronization programs.

    PubMed

    Krumme, Alexis A; Isaman, Danielle L; Stolpe, Samuel F; Dougherty, Samantha; Choudhry, Niteesh K

    2016-03-01

    The burden of visiting pharmacies to fill medications is a central contributor to nonadherence to maintenance medications. Recently, pharmacies have begun offering services that align prescription fill dates to allow patients to pick up all medications on a single visit. We evaluated the prevalence and structure of synchronization programs and evidence of their impact on adherence and clinical outcomes. Mixed-methods approach consisting of semi-structured interviews, data from surveillance activities, and a systematic literature review. We conducted interviews with opinion leaders from nonprofit advocacy organizations and exemplary synchronization programs. Program prevalence was determined using data from regular surveillance efforts. A literature review included Medline, EMBASE, Google Scholar, and general Internet searches. Synchronization programs exist in approximately 10% of independent, 6% of stand-alone chain, and 11% of retail store pharmacies. The majority of programs include a monthly pharmacist appointment and reminder communication. Programs reported the importance of pharmacist buy-in, technology to track and recruit patients, links to other healthcare services, and flexible solutions for managing costs and communication preferences. Although existing peer-reviewed literature suggests that synchronization improves adherence, more evidence is needed to evaluate its impact on patient-centered outcomes. As medication synchronization programs shift directions and compete for patients and payer resources, it will be more important than ever to rigorously evaluate their ability to improve clinical outcomes while also providing the growing number of patients managing multiple chronic conditions with the highest level of patient engagement and consumer choice.

  13. Technology Preparation of K-6 Elementary Education Teachers in University System of New Hampshire Post-Secondary Programs and Technology Utilization in the New Hampshire K-6 Classroom: A Study of Alignment

    ERIC Educational Resources Information Center

    Marks, Nicholas W.

    2016-01-01

    The purpose of this study was to determine whether there is alignment between post-secondary institutions' technology training preparation of teachers and the use of technology in K-6 schools in the State of New Hampshire. For the purpose of the study, alignment is defined as the correlation of specific technology preparation for teachers to…

  14. Enhancing Teaching through Constructive Alignment.

    ERIC Educational Resources Information Center

    Biggs, John

    1996-01-01

    An approach to college-level instructional design that incorporates the principles of constructivism, termed "constructive alignment," is described. The process is then illustrated with reference to a professional development unit in educational psychology for teachers, but the model is viewed as generalizable to most units or programs in higher…

  15. Dynamical differences of hemoglobin and the ionotropic glutamate receptor in different states revealed by a new dynamics alignment method.

    PubMed

    Tobi, Dror

    2017-08-01

    A new algorithm for comparison of protein dynamics is presented. Compared protein structures are superposed and their modes of motions are calculated using the anisotropic network model. The obtained modes are aligned using the dynamic programming algorithm of Needleman and Wunsch, commonly used for sequence alignment. Dynamical comparison of hemoglobin in the T and R2 states reveals that the dynamics of the allosteric effector 2,3-bisphosphoglycerate binding site is different in the two states. These differences can contribute to the selectivity of the effector to the T state. Similar comparison of the ionotropic glutamate receptor in the kainate+(R,R)-2b and ZK bound states reveals that the kainate+(R,R)-2b bound states slow modes describe upward motions of ligand binding domain and the transmembrane domain regions. Such motions may lead to the opening of the receptor. The upper lobes of the LBDs of the ZK bound state have a smaller interface with the amino terminal domains above them and have a better ability to move together. The present study exemplifies the use of dynamics comparison as a tool to study protein function. Proteins 2017; 85:1507-1517. © 2014 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Implementation Processes and Pay for Performance in Healthcare: A Systematic Review.

    PubMed

    Kondo, Karli K; Damberg, Cheryl L; Mendelson, Aaron; Motu'apuaka, Makalapua; Freeman, Michele; O'Neil, Maya; Relevo, Rose; Low, Allison; Kansagara, Devan

    2016-04-01

    Over the last decade, various pay-for-performance (P4P) programs have been implemented to improve quality in health systems, including the VHA. P4P programs are complex, and their effects may vary by design, context, and other implementation processes. We conducted a systematic review and key informant (KI) interviews to better understand the implementation factors that modify the effectiveness of P4P. We searched PubMed, PsycINFO, and CINAHL through April 2014, and reviewed reference lists. We included trials and observational studies of P4P implementation. Two investigators abstracted data and assessed study quality. We interviewed P4P researchers to gain further insight. Among 1363 titles and abstracts, we selected 509 for full-text review, and included 41 primary studies. Of these 41 studies, 33 examined P4P programs in ambulatory settings, 7 targeted hospitals, and 1 study applied to nursing homes. Related to implementation, 13 studies examined program design, 8 examined implementation processes, 6 the outer setting, 18 the inner setting, and 5 provider characteristics. Results suggest the importance of considering underlying payment models and using statistically stringent methods of composite measure development, and ensuring that high-quality care will be maintained after incentive removal. We found no conclusive evidence that provider or practice characteristics relate to P4P effectiveness. Interviews with 14 KIs supported limited evidence that effective P4P program measures should be aligned with organizational goals, that incentive structures should be carefully considered, and that factors such as a strong infrastructure and public reporting may have a large influence. There is limited evidence from which to draw firm conclusions related to P4P implementation. Findings from studies and KI interviews suggest that P4P programs should undergo regular evaluation and should target areas of poor performance. Additionally, measures and incentives should align with organizational priorities, and programs should allow for changes over time in response to data and provider input.

  17. Community detection in sequence similarity networks based on attribute clustering

    DOE PAGES

    Chowdhary, Janamejaya; Loeffler, Frank E.; Smith, Jeremy C.

    2017-07-24

    Networks are powerful tools for the presentation and analysis of interactions in multi-component systems. A commonly studied mesoscopic feature of networks is their community structure, which arises from grouping together similar nodes into one community and dissimilar nodes into separate communities. Here in this paper, the community structure of protein sequence similarity networks is determined with a new method: Attribute Clustering Dependent Communities (ACDC). Sequence similarity has hitherto typically been quantified by the alignment score or its expectation value. However, pair alignments with the same score or expectation value cannot thus be differentiated. To overcome this deficiency, the method constructs,more » for pair alignments, an extended alignment metric, the link attribute vector, which includes the score and other alignment characteristics. Rescaling components of the attribute vectors qualitatively identifies a systematic variation of sequence similarity within protein superfamilies. The problem of community detection is then mapped to clustering the link attribute vectors, selection of an optimal subset of links and community structure refinement based on the partition density of the network. ACDC-predicted communities are found to be in good agreement with gold standard sequence databases for which the "ground truth" community structures (or families) are known. ACDC is therefore a community detection method for sequence similarity networks based entirely on pair similarity information. A serial implementation of ACDC is available from https://cmb.ornl.gov/resources/developments« less

  18. Binocular contrast-gain control for natural scenes: Image structure and phase alignment.

    PubMed

    Huang, Pi-Chun; Dai, Yu-Ming

    2018-05-01

    In the context of natural scenes, we applied the pattern-masking paradigm to investigate how image structure and phase alignment affect contrast-gain control in binocular vision. We measured the discrimination thresholds of bandpass-filtered natural-scene images (targets) under various types of pedestals. Our first experiment had four pedestal types: bandpass-filtered pedestals, unfiltered pedestals, notch-filtered pedestals (which enabled removal of the spatial frequency), and misaligned pedestals (which involved rotation of unfiltered pedestals). Our second experiment featured six types of pedestals: bandpass-filtered, unfiltered, and notch-filtered pedestals, and the corresponding phase-scrambled pedestals. The thresholds were compared for monocular, binocular, and dichoptic viewing configurations. The bandpass-filtered pedestal and unfiltered pedestals showed classic dipper shapes; the dipper shapes of the notch-filtered, misaligned, and phase-scrambled pedestals were weak. We adopted a two-stage binocular contrast-gain control model to describe our results. We deduced that the phase-alignment information influenced the contrast-gain control mechanism before the binocular summation stage and that the phase-alignment information and structural misalignment information caused relatively strong divisive inhibition in the monocular and interocular suppression stages. When the pedestals were phase-scrambled, the elimination of the interocular suppression processing was the most convincing explanation of the results. Thus, our results indicated that both phase-alignment information and similar image structures cause strong interocular suppression. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Collective motion of active Brownian particles with polar alignment.

    PubMed

    Martín-Gómez, Aitor; Levis, Demian; Díaz-Guilera, Albert; Pagonabarraga, Ignacio

    2018-04-04

    We present a comprehensive computational study of the collective behavior emerging from the competition between self-propulsion, excluded volume interactions and velocity-alignment in a two-dimensional model of active particles. We consider an extension of the active brownian particles model where the self-propulsion direction of the particles aligns with the one of their neighbors. We analyze the onset of collective motion (flocking) in a low-density regime (10% surface area) and show that it is mainly controlled by the strength of velocity-alignment interactions: the competition between self-propulsion and crowding effects plays a minor role in the emergence of flocking. However, above the flocking threshold, the system presents a richer pattern formation scenario than analogous models without alignment interactions (active brownian particles) or excluded volume effects (Vicsek-like models). Depending on the parameter regime, the structure of the system is characterized by either a broad distribution of finite-sized polar clusters or the presence of an amorphous, highly fluctuating, large-scale traveling structure which can take a lane-like or band-like form (and usually a hybrid structure which is halfway in between both). We establish a phase diagram that summarizes collective behavior of polar active brownian particles and propose a generic mechanism to describe the complexity of the large-scale structures observed in systems of repulsive self-propelled particles.

  20. Evolutionary profiles from the QR factorization of multiple sequence alignments

    PubMed Central

    Sethi, Anurag; O'Donoghue, Patrick; Luthey-Schulten, Zaida

    2005-01-01

    We present an algorithm to generate complete evolutionary profiles that represent the topology of the molecular phylogenetic tree of the homologous group. The method, based on the multidimensional QR factorization of numerically encoded multiple sequence alignments, removes redundancy from the alignments and orders the protein sequences by increasing linear dependence, resulting in the identification of a minimal basis set of sequences that spans the evolutionary space of the homologous group of proteins. We observe a general trend that these smaller, more evolutionarily balanced profiles have comparable and, in many cases, better performance in database searches than conventional profiles containing hundreds of sequences, constructed in an iterative and computationally intensive procedure. For more diverse families or superfamilies, with sequence identity <30%, structural alignments, based purely on the geometry of the protein structures, provide better alignments than pure sequence-based methods. Merging the structure and sequence information allows the construction of accurate profiles for distantly related groups. These structure-based profiles outperformed other sequence-based methods for finding distant homologs and were used to identify a putative class II cysteinyl-tRNA synthetase (CysRS) in several archaea that eluded previous annotation studies. Phylogenetic analysis showed the putative class II CysRSs to be a monophyletic group and homology modeling revealed a constellation of active site residues similar to that in the known class I CysRS. PMID:15741270

  1. Community detection in sequence similarity networks based on attribute clustering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chowdhary, Janamejaya; Loeffler, Frank E.; Smith, Jeremy C.

    Networks are powerful tools for the presentation and analysis of interactions in multi-component systems. A commonly studied mesoscopic feature of networks is their community structure, which arises from grouping together similar nodes into one community and dissimilar nodes into separate communities. Here in this paper, the community structure of protein sequence similarity networks is determined with a new method: Attribute Clustering Dependent Communities (ACDC). Sequence similarity has hitherto typically been quantified by the alignment score or its expectation value. However, pair alignments with the same score or expectation value cannot thus be differentiated. To overcome this deficiency, the method constructs,more » for pair alignments, an extended alignment metric, the link attribute vector, which includes the score and other alignment characteristics. Rescaling components of the attribute vectors qualitatively identifies a systematic variation of sequence similarity within protein superfamilies. The problem of community detection is then mapped to clustering the link attribute vectors, selection of an optimal subset of links and community structure refinement based on the partition density of the network. ACDC-predicted communities are found to be in good agreement with gold standard sequence databases for which the "ground truth" community structures (or families) are known. ACDC is therefore a community detection method for sequence similarity networks based entirely on pair similarity information. A serial implementation of ACDC is available from https://cmb.ornl.gov/resources/developments« less

  2. Structural and electronic properties of CdS/ZnS core/shell nanowires: A first-principles study

    NASA Astrophysics Data System (ADS)

    Kim, Hyo Seok; Kim, Yong-Hoon

    2015-03-01

    Carrying out density functional theory (DFT) calculation, we studied the relative effects of quantum confinement and strain on the electronic structures of II-IV semiconductor compounds with a large lattice-mismatch, CdS and ZnS, in the core/shell nanowire geometry. We considered different core radii and shell thickness of the CdS/ZnS core/shell nanowire, different surface facets, and various defects in the core/shell interface and surface regions. To properly describe the band level alignment at the core/shell boundary, we adopted the self-interaction correction (SIC)-DFT scheme. Implications of our findings in the context of device applications will be also discussed. This work was supported by the Basic Science Research Grant (No. 2012R1A1A2044793), Global Frontier Program (No. 2013-073298), and Nano-Material Technology Development Program (2012M3A7B4049888) of the National Research Foundation funded by the Ministry of Education, Science and Technology of Korea. Corresponding author

  3. The ConSurf-DB: pre-calculated evolutionary conservation profiles of protein structures.

    PubMed

    Goldenberg, Ofir; Erez, Elana; Nimrod, Guy; Ben-Tal, Nir

    2009-01-01

    ConSurf-DB is a repository for evolutionary conservation analysis of the proteins of known structures in the Protein Data Bank (PDB). Sequence homologues of each of the PDB entries were collected and aligned using standard methods. The evolutionary conservation of each amino acid position in the alignment was calculated using the Rate4Site algorithm, implemented in the ConSurf web server. The algorithm takes into account the phylogenetic relations between the aligned proteins and the stochastic nature of the evolutionary process explicitly. Rate4Site assigns a conservation level for each position in the multiple sequence alignment using an empirical Bayesian inference. Visual inspection of the conservation patterns on the 3D structure often enables the identification of key residues that comprise the functionally important regions of the protein. The repository is updated with the latest PDB entries on a monthly basis and will be rebuilt annually. ConSurf-DB is available online at http://consurfdb.tau.ac.il/

  4. The ConSurf-DB: pre-calculated evolutionary conservation profiles of protein structures

    PubMed Central

    Goldenberg, Ofir; Erez, Elana; Nimrod, Guy; Ben-Tal, Nir

    2009-01-01

    ConSurf-DB is a repository for evolutionary conservation analysis of the proteins of known structures in the Protein Data Bank (PDB). Sequence homologues of each of the PDB entries were collected and aligned using standard methods. The evolutionary conservation of each amino acid position in the alignment was calculated using the Rate4Site algorithm, implemented in the ConSurf web server. The algorithm takes into account the phylogenetic relations between the aligned proteins and the stochastic nature of the evolutionary process explicitly. Rate4Site assigns a conservation level for each position in the multiple sequence alignment using an empirical Bayesian inference. Visual inspection of the conservation patterns on the 3D structure often enables the identification of key residues that comprise the functionally important regions of the protein. The repository is updated with the latest PDB entries on a monthly basis and will be rebuilt annually. ConSurf-DB is available online at http://consurfdb.tau.ac.il/ PMID:18971256

  5. G-LoSA for Prediction of Protein-Ligand Binding Sites and Structures.

    PubMed

    Lee, Hui Sun; Im, Wonpil

    2017-01-01

    Recent advances in high-throughput structure determination and computational protein structure prediction have significantly enriched the universe of protein structure. However, there is still a large gap between the number of available protein structures and that of proteins with annotated function in high accuracy. Computational structure-based protein function prediction has emerged to reduce this knowledge gap. The identification of a ligand binding site and its structure is critical to the determination of a protein's molecular function. We present a computational methodology for predicting small molecule ligand binding site and ligand structure using G-LoSA, our protein local structure alignment and similarity measurement tool. All the computational procedures described here can be easily implemented using G-LoSA Toolkit, a package of standalone software programs and preprocessed PDB structure libraries. G-LoSA and G-LoSA Toolkit are freely available to academic users at http://compbio.lehigh.edu/GLoSA . We also illustrate a case study to show the potential of our template-based approach harnessing G-LoSA for protein function prediction.

  6. Demonstration of a Monolithic Micro-Spectrometer System

    NASA Technical Reports Server (NTRS)

    Rajic, S.; Egert, C. M.

    1995-01-01

    The starting design of a spectrometer based on a modified Czerny-Turner configuration containing five precision surfaces encapsulated in a monolithic structure is described. Since the purpose at the early stages of the development was to demonstrate the feasibility of the technology and not an attempt to address a specific sensing problem, the first substrate material chosen was optical quality polymethyl methacrylate (PMMA). The final system design decision was narrowed down to two possible configurations containing five and six precision surfaces. The five surface design was chosen since it contained one less precision optical surface, yet included multiple off-axis spheres. In this particular design and material system, the mass was kept below 7 g. The wavelength range (bandpass) design goal was 1 micrometer (0.6 - 1.6 micrometers). The PMMA is particularly transparent in this wavelength region and there are interesting effects to monitor within this band. The optical system was designed and optimized using the ZEMAX optical design software program to be entirely alignment free (self aligning).

  7. Using The GLOBE Program to address the Global Development Goals

    NASA Astrophysics Data System (ADS)

    Wegner, K.; Murphy, T.; Wigbels, L.; Mauriello, H.; Kucera, P. A.

    2016-12-01

    The GLOBE Program (globe.gov) is an international science and education program in more than 110 countries that provides students and the public worldwide the opportunity to participate in the scientific process through Earth observations and geospatial information. To address the Global Goals for Sustainable Development, The GLOBE Program has collaborated with with international organizations such as the UNEP, Peace Corps, USAID, UNESCO, Eco-Schools, and SciStarter to address the Goals for Sustainable Development. In this presentation, GLOBE will share the alignment materials that they have created to provide pathways to achieving the goals, as well as present case studies that demonstrate how the GLOBE community uses GLOBE protocols as Earth observations to monitor and communicate environmental indicators aligned to the Global Development Goals.

  8. Structure based alignment and clustering of proteins (STRALCP)

    DOEpatents

    Zemla, Adam T.; Zhou, Carol E.; Smith, Jason R.; Lam, Marisa W.

    2013-06-18

    Disclosed are computational methods of clustering a set of protein structures based on local and pair-wise global similarity values. Pair-wise local and global similarity values are generated based on pair-wise structural alignments for each protein in the set of protein structures. Initially, the protein structures are clustered based on pair-wise local similarity values. The protein structures are then clustered based on pair-wise global similarity values. For each given cluster both a representative structure and spans of conserved residues are identified. The representative protein structure is used to assign newly-solved protein structures to a group. The spans are used to characterize conservation and assign a "structural footprint" to the cluster.

  9. High performance ultracapacitors with carbon nanomaterials and ionic liquids

    DOEpatents

    Lu, Wen; Henry, Kent Douglas

    2012-10-09

    The present invention is directed to the use of carbon nanotubes and/or electrolyte structures in various electrochemical devices, such as ultracapacitors having an ionic liquid electrolyte. The carbon nanotubes are preferably aligned carbon nanotubes. Compared to randomly entangled carbon nanotubes, aligned carbon nanotubes can have better defined pore structures and higher specific surface areas.

  10. FoldMiner and LOCK 2: protein structure comparison and motif discovery on the web.

    PubMed

    Shapiro, Jessica; Brutlag, Douglas

    2004-07-01

    The FoldMiner web server (http://foldminer.stanford.edu/) provides remote access to methods for protein structure alignment and unsupervised motif discovery. FoldMiner is unique among such algorithms in that it improves both the motif definition and the sensitivity of a structural similarity search by combining the search and motif discovery methods and using information from each process to enhance the other. In a typical run, a query structure is aligned to all structures in one of several databases of single domain targets in order to identify its structural neighbors and to discover a motif that is the basis for the similarity among the query and statistically significant targets. This process is fully automated, but options for manual refinement of the results are available as well. The server uses the Chime plugin and customized controls to allow for visualization of the motif and of structural superpositions. In addition, we provide an interface to the LOCK 2 algorithm for rapid alignments of a query structure to smaller numbers of user-specified targets.

  11. Streamlined design and self reliant hardware for active control of precision space structures

    NASA Technical Reports Server (NTRS)

    Hyland, David C.; King, James A.; Phillips, Douglas J.

    1994-01-01

    Precision space structures may require active vibration control to satisfy critical performance requirements relating to line-of-sight pointing accuracy and the maintenance of precise, internal alignments. In order for vibration control concepts to become operational, it is necessary that their benefits be practically demonstrated in large scale ground-based experiments. A unique opportunity to carry out such demonstrations on a wide variety of experimental testbeds was provided by the NASA Control-Structure Integration (CSI) Guest Investigator (GI) Program. This report surveys the experimental results achieved by the Harris Corporation GI team on both Phases 1 and 2 of the program and provides a detailed description of Phase 2 activities. The Phase 1 results illustrated the effectiveness of active vibration control for space structures and demonstrated a systematic methodology for control design, implementation test. In Phase 2, this methodology was significantly streamlined to yield an on-site, single session design/test capability. Moreover, the Phase 2 research on adaptive neural control techniques made significant progress toward fully automated, self-reliant space structure control systems. As a further thrust toward productized, self-contained vibration control systems, the Harris Phase II activity concluded with experimental demonstration of new vibration isolation hardware suitable for a wide range of space-flight and ground-based commercial applications.The CSI GI Program Phase 1 activity was conducted under contract NASA1-18872, and the Phase 2 activity was conducted under NASA1-19372.

  12. SNPServer: a real-time SNP discovery tool.

    PubMed

    Savage, David; Batley, Jacqueline; Erwin, Tim; Logan, Erica; Love, Christopher G; Lim, Geraldine A C; Mongin, Emmanuel; Barker, Gary; Spangenberg, German C; Edwards, David

    2005-07-01

    SNPServer is a real-time flexible tool for the discovery of SNPs (single nucleotide polymorphisms) within DNA sequence data. The program uses BLAST, to identify related sequences, and CAP3, to cluster and align these sequences. The alignments are parsed to the SNP discovery software autoSNP, a program that detects SNPs and insertion/deletion polymorphisms (indels). Alternatively, lists of related sequences or pre-assembled sequences may be entered for SNP discovery. SNPServer and autoSNP use redundancy to differentiate between candidate SNPs and sequence errors. For each candidate SNP, two measures of confidence are calculated, the redundancy of the polymorphism at a SNP locus and the co-segregation of the candidate SNP with other SNPs in the alignment. SNPServer is available at http://hornbill.cspp.latrobe.edu.au/snpdiscovery.html.

  13. Pattern formation of frictional fingers in a gravitational potential

    NASA Astrophysics Data System (ADS)

    Eriksen, Jon Alm; Toussaint, Renaud; Mâløy, Knut Jørgen; Flekkøy, Eirik; Galland, Olivier; Sandnes, Bjørnar

    2018-01-01

    Aligned finger structures, with a characteristic width, emerge during the slow drainage of a liquid-granular mixture in a tilted Hele-Shaw cell. A transition from vertical to horizontal alignment of the finger structures is observed as the tilting angle and the granular density are varied. An analytical model is presented, demonstrating that the alignment properties are the result of the competition between fluctuating granular stresses and the hydrostatic pressure. The dynamics is reproduced in simulations. We also show how the system explains patterns observed in nature, created during the early stages of a dike formation.

  14. Method for vacuum fusion bonding

    DOEpatents

    Ackler, Harold D.; Swierkowski, Stefan P.; Tarte, Lisa A.; Hicks, Randall K.

    2001-01-01

    An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.

  15. Synthesis and orientation of barium hexaferrite ceramics by magnetic alignment

    NASA Astrophysics Data System (ADS)

    Autissier, Denis

    1990-01-01

    Particles of Ba 2Mn xZn 2- xFe 12O 22 with planar structure were prepared by chemical precipitation. They were processed by sleep casting in presence of a magnetic field. The degree of alignment was improved by a special sintering treatment. By this procedure an alignment as high as 99.9% is obtained.

  16. Aligning library instruction with the needs of basic sciences graduate students: a case study

    PubMed Central

    O'Malley, Donna; Delwiche, Frances A.

    2012-01-01

    Question: How can an existing library instruction program be reconfigured to reach basic sciences graduate students and other patrons missed by curriculum-based instruction? Setting: The setting is an academic health sciences library that serves both the university and its affiliated teaching hospital. Methods: The existing program was redesigned to incorporate a series of seven workshops that encompassed the range of information literacy skills that graduate students in the basic sciences need. In developing the new model, the teaching librarians made changes in pedagogy, technology, marketing, and assessment strategies. Results: Total attendance at the sessions increased substantially in the first 2 years of the new model, increasing from an average of 20 per semester to an average of 124. Survey results provided insight about what patrons wanted to learn and how best to teach it. Conclusion: Modifying the program's content and structure resulted in a program that appealed to the target audience. PMID:23133328

  17. Relations between Student Perceptions of Assessment Authenticity, Study Approaches and Learning Outcome

    ERIC Educational Resources Information Center

    Gulikers, Judith T. M.; Bastiaens, Theo J.; Kirschner, Paul A.; Kester, Liesbeth

    2006-01-01

    This article examines the relationships between perceptions of authenticity and alignment on study approach and learning outcome. Senior students of a vocational training program performed an authentic assessment and filled in a questionnaire about the authenticity of various assessment characteristics and the alignment between the assessment and…

  18. Minnesota Frameworks for Career and Technical Education

    ERIC Educational Resources Information Center

    Minnesota Department of Education, 2004

    2004-01-01

    This framework provides tools for determining how national and industry standards align with goals and curriculum in Career and Technical Education (CTE) programs. The examples, alignment charts, and ideas for activities contained in this document are intended to encourage districts, sites, and teachers to use, adapt, and develop their own best…

  19. Does Test Item Performance Increase with Test-to-Standards Alignment?

    ERIC Educational Resources Information Center

    Traynor, Anne

    2017-01-01

    Variation in test performance among examinees from different regions or national jurisdictions is often partially attributed to differences in the degree of content correspondence between local school or training program curricula, and the test of interest. This posited relationship between test-curriculum correspondence, or "alignment,"…

  20. Detection and sequence/structure mapping of biophysical constraints to protein variation in saturated mutational libraries and protein sequence alignments with a dedicated server.

    PubMed

    Abriata, Luciano A; Bovigny, Christophe; Dal Peraro, Matteo

    2016-06-17

    Protein variability can now be studied by measuring high-resolution tolerance-to-substitution maps and fitness landscapes in saturated mutational libraries. But these rich and expensive datasets are typically interpreted coarsely, restricting detailed analyses to positions of extremely high or low variability or dubbed important beforehand based on existing knowledge about active sites, interaction surfaces, (de)stabilizing mutations, etc. Our new webserver PsychoProt (freely available without registration at http://psychoprot.epfl.ch or at http://lucianoabriata.altervista.org/psychoprot/index.html ) helps to detect, quantify, and sequence/structure map the biophysical and biochemical traits that shape amino acid preferences throughout a protein as determined by deep-sequencing of saturated mutational libraries or from large alignments of naturally occurring variants. We exemplify how PsychoProt helps to (i) unveil protein structure-function relationships from experiments and from alignments that are consistent with structures according to coevolution analysis, (ii) recall global information about structural and functional features and identify hitherto unknown constraints to variation in alignments, and (iii) point at different sources of variation among related experimental datasets or between experimental and alignment-based data. Remarkably, metabolic costs of the amino acids pose strong constraints to variability at protein surfaces in nature but not in the laboratory. This and other differences call for caution when extrapolating results from in vitro experiments to natural scenarios in, for example, studies of protein evolution. We show through examples how PsychoProt can be a useful tool for the broad communities of structural biology and molecular evolution, particularly for studies about protein modeling, evolution and design.

  1. Redesigning and aligning assessment and evaluation for a federally funded math and science teacher educational program.

    PubMed

    Hardré, Patricia L; Slater, Janis; Nanny, Mark

    2010-11-01

    This paper examines the redesign of evaluation components for a teacher professional development project funded by the National Science Foundation. It focuses on aligning evaluation instrumentation and strategies with program goals, research goals and program evaluation best practices. The study identifies weaknesses in the original (year 1) program evaluation design and implementation, develops strategies and tracks changes for year 2 implementation, and then reports enhancement of findings and recommendations for year 3. It includes lessons learned about assessment and evaluation over the project lifespan, with implications for research and evaluation of a range of related programs. This study functions as a classic illustration of how critical it is to observe first principles of assessment and evaluation for funded programs, the risks that arise when they are ignored, and the benefits that accrue when they are systematically observed. Copyright (c) 2009. Published by Elsevier Ltd.

  2. Arc Second Alignment of International X-Ray Observatory Mirror Segments in a Fixed Structure

    NASA Technical Reports Server (NTRS)

    Evans, Tyler C.; Chan, Kai-Wing

    2009-01-01

    The optics for the International X-Ray Observatory (IXO) require alignment and integration of about fourteen thousand thin mirror segments to achieve the mission goal of 3.0 square meters of effective area at 1.25 keV with an angular resolution of five arc seconds. These mirror segments are 0.4mm thick, and 200 to 400mm in size, which makes it hard not to impart distortion at the subarc second level. This paper outlines the precise alignment, verification testing, and permanent bonding techniques developed at NASA's Goddard Space Flight Center (GSFC). These techniques are used to overcome the challenge of transferring thin mirror segments from a temporary mount to a fixed structure with arc second alignment and minimal figure distortion. Recent advances in technology development in addition to the automation of several processes have produced significant results. This paper will highlight the recent advances in alignment, testing, and permanent bonding techniques as well as the results they have produced.

  3. Passively aligned multichannel fiber-pigtailing of planar integrated optical waveguides

    NASA Astrophysics Data System (ADS)

    Kremmel, Johannes; Lamprecht, Tobias; Crameri, Nino; Michler, Markus

    2017-02-01

    A silicon device to simplify the coupling of multiple single-mode fibers to embedded single-mode waveguides has been developed. The silicon device features alignment structures that enable a passive alignment of fibers to integrated waveguides. For passive alignment, precisely machined V-grooves on a silicon device are used and the planar lightwave circuit board features high-precision structures acting as a mechanical stop. The approach has been tested for up to eight fiber-to-waveguide connections. The alignment approach, the design, and the fabrication of the silicon device as well as the assembly process are presented. The characterization of the fiber-to-waveguide link reveals total coupling losses of (0.45±0.20 dB) per coupling interface, which is significantly lower than the values reported in earlier works. Subsequent climate tests reveal that the coupling losses remain stable during thermal cycling but increases significantly during an 85°C/85 Rh-test. All applied fabrication and bonding steps have been performed using standard MOEMS fabrication and packaging processes.

  4. Arc-Second Alignment of International X-Ray Observatory Mirror Segments in a Fixed Structure

    NASA Technical Reports Server (NTRS)

    Evans, Tyler C.; Chan, Kai-Wing; Saha, Timo T.

    2010-01-01

    The optics for the International X-Ray Observatory (IXO) require alignment and integration of about fourteen thousand thin mirror segments to achieve the mission goal of 3.0 square meters of effective area at 1.25 keV with an angular resolution of five arc-seconds. These mirror segments are 0.4 mm thick, and 200 to 400 mm in size, which makes it hard not to impart distortion at the subare- second level. This paper outlines the precise alignment, verification testing, and permanent bonding techniques developed at NASA's Goddard Space Flight Center (GSFC). These techniques are used to overcome the challenge of transferring thin mirror segments from a temporary mount to a fixed structure with arc-second alignment and minimal figure distortion. Recent advances in technology development in addition to the automation of several processes have produced significant results. This paper will highlight the recent advances in alignment, testing, and permanent bonding techniques as well as the results they have produced.

  5. Fabrication and material properties of fibrous PHBV scaffolds depending on the cross-ply angle for tissue engineering.

    PubMed

    Kim, Yang-Hee; Min, Young-Ki; Lee, Byong-Taek

    2012-11-01

    Fibrous PHBV cross-ply scaffolds were fabricated using the electrospinning technique. The electrospun fibers were arranged depending on angles of alignment, which were 180°, 90°, 60°, and 45°. The stress and strain values of the fibrous PHBV cross-ply scaffolds increased as the cross-ply angle increased. At 180°, the strength and strain values of the fibers depended on tensile loading directions. At an alignment of 90°, the PHBV scaffolds had a stress value of 3.5 MPa, which was more than two times higher than the random structure. The cell morphology and proliferation of L-929 cells was strongly dependant on the fiber alignment and the best results were observed when the angle alignment was high. The results of this study showed that the cross-ply structure of the PHBV scaffold affected not only the cell adhesion and spreading properties but also dictated the mechanical properties, which were dependent on the angles of alignment.

  6. MetAlign: interface-driven, versatile metabolomics tool for hyphenated full-scan mass spectrometry data preprocessing.

    PubMed

    Lommen, Arjen

    2009-04-15

    Hyphenated full-scan MS technology creates large amounts of data. A versatile easy to handle automation tool aiding in the data analysis is very important in handling such a data stream. MetAlign softwareas described in this manuscripthandles a broad range of accurate mass and nominal mass GC/MS and LC/MS data. It is capable of automatic format conversions, accurate mass calculations, baseline corrections, peak-picking, saturation and mass-peak artifact filtering, as well as alignment of up to 1000 data sets. A 100 to 1000-fold data reduction is achieved. MetAlign software output is compatible with most multivariate statistics programs.

  7. PhyreStorm: A Web Server for Fast Structural Searches Against the PDB.

    PubMed

    Mezulis, Stefans; Sternberg, Michael J E; Kelley, Lawrence A

    2016-02-22

    The identification of structurally similar proteins can provide a range of biological insights, and accordingly, the alignment of a query protein to a database of experimentally determined protein structures is a technique commonly used in the fields of structural and evolutionary biology. The PhyreStorm Web server has been designed to provide comprehensive, up-to-date and rapid structural comparisons against the Protein Data Bank (PDB) combined with a rich and intuitive user interface. It is intended that this facility will enable biologists inexpert in bioinformatics access to a powerful tool for exploring protein structure relationships beyond what can be achieved by sequence analysis alone. By partitioning the PDB into similar structures, PhyreStorm is able to quickly discard the majority of structures that cannot possibly align well to a query protein, reducing the number of alignments required by an order of magnitude. PhyreStorm is capable of finding 93±2% of all highly similar (TM-score>0.7) structures in the PDB for each query structure, usually in less than 60s. PhyreStorm is available at http://www.sbg.bio.ic.ac.uk/phyrestorm/. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Effect of mat pilates exercise on postural alignment and body composition of middle-aged women

    PubMed Central

    Lee, Hyo Taek; Oh, Hyun Ok; Han, Hui Seung; Jin, Kwang Youn; Roh, Hyo Lyun

    2016-01-01

    [Purpose] This study attempted to examine whether Pilates is an effective exercise for improving the postural alignment and health of middle-aged women. [Subjects and Methods] The participants in this study were 36 middle-aged women (20 in the experimental group, 16 in the control group). The experimental group participated in Pilates exercise sessions three times a week for 12 weeks. Body alignment and composition measurements before and after applying the Pilates exercise program were performed with a body composition analyzer and a three-dimensional scanner. [Results] Postural alignment in the sagittal and horizontal planes was enhanced in the Pilates exercise group. Trunk alignment showed correlations with body fat and muscle mass. [Conclusion] The Pilates exercises are performed symmetrically and strengthen the deep muscles. Moreover, the results showed that muscle mass was correlated with trunk postural alignment and that the proper amount of muscle is critical in maintaining trunk postural alignment. PMID:27390396

  9. Automatic Data Distribution for CFD Applications on Structured Grids

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Yan, Jerry

    2000-01-01

    Data distribution is an important step in implementation of any parallel algorithm. The data distribution determines data traffic, utilization of the interconnection network and affects the overall code efficiency. In recent years a number data distribution methods have been developed and used in real programs for improving data traffic. We use some of the methods for translating data dependence and affinity relations into data distribution directives. We describe an automatic data alignment and placement tool (ADAFT) which implements these methods and show it results for some CFD codes (NPB and ARC3D). Algorithms for program analysis and derivation of data distribution implemented in ADAFT are efficient three pass algorithms. Most algorithms have linear complexity with the exception of some graph algorithms having complexity O(n(sup 4)) in the worst case.

  10. Automatic Data Distribution for CFD Applications on Structured Grids

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Yan, Jerry

    1999-01-01

    Data distribution is an important step in implementation of any parallel algorithm. The data distribution determines data traffic, utilization of the interconnection network and affects the overall code efficiency. In recent years a number data distribution methods have been developed and used in real programs for improving data traffic. We use some of the methods for translating data dependence and affinity relations into data distribution directives. We describe an automatic data alignment and placement tool (ADAPT) which implements these methods and show it results for some CFD codes (NPB and ARC3D). Algorithms for program analysis and derivation of data distribution implemented in ADAPT are efficient three pass algorithms. Most algorithms have linear complexity with the exception of some graph algorithms having complexity O(n(sup 4)) in the worst case.

  11. A Facile Method to Fabricate Anisotropic Hydrogels with Perfectly Aligned Hierarchical Fibrous Structures.

    PubMed

    Mredha, Md Tariful Islam; Guo, Yun Zhou; Nonoyama, Takayuki; Nakajima, Tasuku; Kurokawa, Takayuki; Gong, Jian Ping

    2018-03-01

    Natural structural materials (such as tendons and ligaments) are comprised of multiscale hierarchical architectures, with dimensions ranging from nano- to macroscale, which are difficult to mimic synthetically. Here a bioinspired, facile method to fabricate anisotropic hydrogels with perfectly aligned multiscale hierarchical fibrous structures similar to those of tendons and ligaments is reported. The method includes drying a diluted physical hydrogel in air by confining its length direction. During this process, sufficiently high tensile stress is built along the length direction to align the polymer chains and multiscale fibrous structures (from nano- to submicro- to microscale) are spontaneously formed in the bulk material, which are well-retained in the reswollen gel. The method is useful for relatively rigid polymers (such as alginate and cellulose), which are susceptible to mechanical signal. By controlling the drying with or without prestretching, the degree of alignment, size of superstructures, and the strength of supramolecular interactions can be tuned, which sensitively influence the strength and toughness of the hydrogels. The mechanical properties are comparable with those of natural ligaments. This study provides a general strategy for designing hydrogels with highly ordered hierarchical structures, which opens routes for the development of many functional biomimetic materials for biomedical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. ProfileGrids: a sequence alignment visualization paradigm that avoids the limitations of Sequence Logos

    PubMed Central

    2014-01-01

    Background The 2013 BioVis Contest provided an opportunity to evaluate different paradigms for visualizing protein multiple sequence alignments. Such data sets are becoming extremely large and thus taxing current visualization paradigms. Sequence Logos represent consensus sequences but have limitations for protein alignments. As an alternative, ProfileGrids are a new protein sequence alignment visualization paradigm that represents an alignment as a color-coded matrix of the residue frequency occurring at every homologous position in the aligned protein family. Results The JProfileGrid software program was used to analyze the BioVis contest data sets to generate figures for comparison with the Sequence Logo reference images. Conclusions The ProfileGrid representation allows for the clear and effective analysis of protein multiple sequence alignments. This includes both a general overview of the conservation and diversity sequence patterns as well as the interactive ability to query the details of the protein residue distributions in the alignment. The JProfileGrid software is free and available from http://www.ProfileGrid.org. PMID:25237393

  13. Mechanisms of lamellar collagen formation in connective tissues.

    PubMed

    Ghazanfari, Samaneh; Khademhosseini, Ali; Smit, Theodoor H

    2016-08-01

    The objective of tissue engineering is to regenerate functional tissues. Engineering functional tissues requires an understanding of the mechanisms that guide the formation and evolution of structure in the extracellular matrix (ECM). In particular, the three-dimensional (3D) collagen fiber arrangement is important as it is the key structural determinant that provides mechanical integrity and biological function. In this review, we survey the current knowledge on collagen organization mechanisms that can be applied to create well-structured functional lamellar tissues and in particular intervertebral disc and cornea. Thus far, the mechanisms behind the formation of cross-aligned collagen fibers in the lamellar structures is not fully understood. We start with cell-induced collagen alignment and strain-stabilization behavior mechanisms which can explain a single anisotropically aligned collagen fiber layer. These mechanisms may explain why there is anisotropy in a single layer in the first place. However, they cannot explain why a consecutive collagen layer is laid down with an alternating alignment. Therefore, we explored another mechanism, called liquid crystal phasing. While dense concentrations of collagen show such behavior, there is little evidence that the conditions for liquid crystal phasing are actually met in vivo. Instead, lysyl aldehyde-derived collagen cross-links have been found essential for correct lamellar matrix deposition. Furthermore, we suggest that supra-cellular (tissue-level) shear stress may be instrumental in the alignment of collagen fibers. Understanding the potential mechanisms behind the lamellar collagen structure in connective tissues will lead to further improvement of the regeneration strategies of functional complex lamellar tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Structure and Characterization of Vertically Aligned Single-Walled Carbon Nanotube Bundles

    DOE PAGES

    Márquez, Francisco; López, Vicente; Morant, Carmen; ...

    2010-01-01

    Arrmore » ays of vertically aligned single-walled carbon nanotube bundles, SWCNTs, have been synthesized by simple alcohol catalytic chemical vapor deposition process, carried out at 800 ° C . The formed SWCNTs are organized in small groups perpendicularly aligned and attached to the substrate. These small bundles show a constant diameter of ca. 30 nm and are formed by the adhesion of no more than twenty individual SWCNTs perfectly aligned along their length.« less

  15. Sequence-similar, structure-dissimilar protein pairs in the PDB.

    PubMed

    Kosloff, Mickey; Kolodny, Rachel

    2008-05-01

    It is often assumed that in the Protein Data Bank (PDB), two proteins with similar sequences will also have similar structures. Accordingly, it has proved useful to develop subsets of the PDB from which "redundant" structures have been removed, based on a sequence-based criterion for similarity. Similarly, when predicting protein structure using homology modeling, if a template structure for modeling a target sequence is selected by sequence alone, this implicitly assumes that all sequence-similar templates are equivalent. Here, we show that this assumption is often not correct and that standard approaches to create subsets of the PDB can lead to the loss of structurally and functionally important information. We have carried out sequence-based structural superpositions and geometry-based structural alignments of a large number of protein pairs to determine the extent to which sequence similarity ensures structural similarity. We find many examples where two proteins that are similar in sequence have structures that differ significantly from one another. The source of the structural differences usually has a functional basis. The number of such proteins pairs that are identified and the magnitude of the dissimilarity depend on the approach that is used to calculate the differences; in particular sequence-based structure superpositioning will identify a larger number of structurally dissimilar pairs than geometry-based structural alignments. When two sequences can be aligned in a statistically meaningful way, sequence-based structural superpositioning provides a meaningful measure of structural differences. This approach and geometry-based structure alignments reveal somewhat different information and one or the other might be preferable in a given application. Our results suggest that in some cases, notably homology modeling, the common use of nonredundant datasets, culled from the PDB based on sequence, may mask important structural and functional information. We have established a data base of sequence-similar, structurally dissimilar protein pairs that will help address this problem (http://luna.bioc.columbia.edu/rachel/seqsimstrdiff.htm).

  16. Topologically Micropatterned Collagen and Poly(ε-caprolactone) Struts Fabricated Using the Poly(vinyl alcohol) Fibrillation/Leaching Process To Develop Efficiently Engineered Skeletal Muscle Tissue.

    PubMed

    Kim, Minseong; Kim, WonJin; Kim, GeunHyung

    2017-12-20

    Optimally designed three-dimensional (3D) biomedical scaffolds for skeletal muscle tissue regeneration pose significant research challenges. Currently, most studies on scaffolds focus on the two-dimensional (2D) surface structures that are patterned in the micro-/nanoscales with various repeating sizes and shapes to induce the alignment of myoblasts and myotube formation. The 2D patterned surface clearly provides effective analytical results of pattern size and shape of the myoblast alignment and differentiation. However, it is inconvenient in terms of the direct application for clinical usage due to the limited thickness and 3D shapeability. Hence, the present study suggests an innovative hydrogel or synthetic structure that consists of uniaxially surface-patterned cylindrical struts for skeleton muscle regeneration. The alignment of the pattern on the hydrogel (collagen) and poly(ε-caprolactone) struts was attained with the fibrillation of poly(vinyl alcohol) and the leaching process. Various cell culture results indicate that the C2C12 cells on the micropatterned collagen structure were fully aligned, and that a significantly high level of myotube formation was achieved when compared to the collagen structures that were not treated with the micropatterning process.

  17. Atomistic cluster alignment method for local order mining in liquids and glasses

    NASA Astrophysics Data System (ADS)

    Fang, X. W.; Wang, C. Z.; Yao, Y. X.; Ding, Z. J.; Ho, K. M.

    2010-11-01

    An atomistic cluster alignment method is developed to identify and characterize the local atomic structural order in liquids and glasses. With the “order mining” idea for structurally disordered systems, the method can detect the presence of any type of local order in the system and can quantify the structural similarity between a given set of templates and the aligned clusters in a systematic and unbiased manner. Moreover, population analysis can also be carried out for various types of clusters in the system. The advantages of the method in comparison with other previously developed analysis methods are illustrated by performing the structural analysis for four prototype systems (i.e., pure Al, pure Zr, Zr35Cu65 , and Zr36Ni64 ). The results show that the cluster alignment method can identify various types of short-range orders (SROs) in these systems correctly while some of these SROs are difficult to capture by most of the currently available analysis methods (e.g., Voronoi tessellation method). Such a full three-dimensional atomistic analysis method is generic and can be applied to describe the magnitude and nature of noncrystalline ordering in many disordered systems.

  18. Moire interferometry patterns for rotational alignment of structures

    NASA Astrophysics Data System (ADS)

    Heidari, Esmaeil; Harding, Kevin

    2016-08-01

    In some manufacturing applications the alignment of fine structures formed on the surface of a part such as micro-scribed patterns on solar panels can be critical to the panel performance. Variations in pattern uniformity may degrade the efficiency of the solar panel if the pattern deviates significantly from designed parameters. This paper will explore the use of moire patterns to interpret the angular alignment of such structures on 3 dimensional non-planar shapes. The moire interferometry pattern creates a beat between the scribed pattern and a reference pattern that is a function of both the shape of the part as well as the shape of the scribed pattern. Both the part shape variations and the patterns of interest are typically much smaller than can be seen visually. Similar challenges exist when inspecting specular models or testing low quality optics. The moire effect allows small displacements to be measured from patterns that are well below the resolution of the camera systems that are used to view the patterns. Issues such as the separation of the shape of the part from the alignment of the fine structure as well as resolution and robustness of the technique will be explored in this paper.

  19. Embedding strategies for effective use of information from multiple sequence alignments.

    PubMed Central

    Henikoff, S.; Henikoff, J. G.

    1997-01-01

    We describe a new strategy for utilizing multiple sequence alignment information to detect distant relationships in searches of sequence databases. A single sequence representing a protein family is enriched by replacing conserved regions with position-specific scoring matrices (PSSMs) or consensus residues derived from multiple alignments of family members. In comprehensive tests of these and other family representations, PSSM-embedded queries produced the best results overall when used with a special version of the Smith-Waterman searching algorithm. Moreover, embedding consensus residues instead of PSSMs improved performance with readily available single sequence query searching programs, such as BLAST and FASTA. Embedding PSSMs or consensus residues into a representative sequence improves searching performance by extracting multiple alignment information from motif regions while retaining single sequence information where alignment is uncertain. PMID:9070452

  20. JavaScript DNA translator: DNA-aligned protein translations.

    PubMed

    Perry, William L

    2002-12-01

    There are many instances in molecular biology when it is necessary to identify ORFs in a DNA sequence. While programs exist for displaying protein translations in multiple ORFs in alignment with a DNA sequence, they are often expensive, exist as add-ons to software that must be purchased, or are only compatible with a particular operating system. JavaScript DNA Translator is a shareware application written in JavaScript, a scripting language interpreted by the Netscape Communicator and Internet Explorer Web browsers, which makes it compatible with several different operating systems. While the program uses a familiar Web page interface, it requires no connection to the Internet since calculations are performed on the user's own computer. The program analyzes one or multiple DNA sequences and generates translations in up to six reading frames aligned to a DNA sequence, in addition to displaying translations as separate sequences in FASTA format. ORFs within a reading frame can also be displayed as separate sequences. Flexible formatting options are provided, including the ability to hide ORFs below a minimum size specified by the user. The program is available free of charge at the BioTechniques Software Library (www.Biotechniques.com).

  1. Differential evolution-simulated annealing for multiple sequence alignment

    NASA Astrophysics Data System (ADS)

    Addawe, R. C.; Addawe, J. M.; Sueño, M. R. K.; Magadia, J. C.

    2017-10-01

    Multiple sequence alignments (MSA) are used in the analysis of molecular evolution and sequence structure relationships. In this paper, a hybrid algorithm, Differential Evolution - Simulated Annealing (DESA) is applied in optimizing multiple sequence alignments (MSAs) based on structural information, non-gaps percentage and totally conserved columns. DESA is a robust algorithm characterized by self-organization, mutation, crossover, and SA-like selection scheme of the strategy parameters. Here, the MSA problem is treated as a multi-objective optimization problem of the hybrid evolutionary algorithm, DESA. Thus, we name the algorithm as DESA-MSA. Simulated sequences and alignments were generated to evaluate the accuracy and efficiency of DESA-MSA using different indel sizes, sequence lengths, deletion rates and insertion rates. The proposed hybrid algorithm obtained acceptable solutions particularly for the MSA problem evaluated based on the three objectives.

  2. Directionally Antagonistic Graphene Oxide-Polyurethane Hybrid Aerogel as a Sound Absorber.

    PubMed

    Oh, Jung-Hwan; Kim, Jieun; Lee, Hyeongrae; Kang, Yeonjune; Oh, Il-Kwon

    2018-06-21

    Innovative sound absorbers, the design of which is based on carbon nanotubes and graphene derivatives, could be used to make more efficient sound absorbing materials because of their excellent intrinsic mechanical and chemical properties. However, controlling the directional alignments of low-dimensional carbon nanomaterials, such as restacking, alignment, and dispersion, has been a challenging problem when developing sound absorbing forms. Herein, we present the directionally antagonistic graphene oxide-polyurethane hybrid aerogel we developed as a sound absorber, the physical properties of which differ according to the alignment of the microscopic graphene oxide sheets. This porous graphene sound absorber has a microporous hierarchical cellular structure with adjustable stiffness and improved sound absorption performance, thereby overcoming the restrictions of both geometric and function-orientated functions. Furthermore, by controlling the inner cell size and aligned structure of graphene oxide layers in this study, we achieved remarkable improvement of the sound absorption performance at low frequency. This improvement is attributed to multiple scattering of incident and reflection waves on the aligned porous surfaces, and air-viscous resistance damping inside interconnected structures between the urethane foam and the graphene oxide network. Two anisotropic sound absorbers based on the directionally antagonistic graphene oxide-polyurethane hybrid aerogels were fabricated. They show remarkable differences owing to the opposite alignment of graphene oxide layers inside the polyurethane foam and are expected to be appropriate for the engineering design of sound absorbers in consideration of the wave direction.

  3. Localization of ultra-low frequency waves in multi-ion plasmas of the planetary magnetosphere

    DOE PAGES

    Kim, Eun -Hwa; Johnson, Jay R.; Lee, Dong -Hun

    2015-01-01

    By adopting a 2D time-dependent wave code, we investigate how mode-converted waves at the Ion-Ion Hybrid (IIH) resonance and compressional waves propagate in 2D density structures with a wide range of field-aligned wavenumbers to background magnetic fields. The simulation results show that the mode-converted waves have continuous bands across the field line consistent with previous numerical studies. These waves also have harmonic structures in frequency domain and are localized in the field-aligned heavy ion density well. Lastly, our results thus emphasize the importance of a field-aligned heavy ion density structure for ultra-low frequency wave propagation, and suggest that IIH wavesmore » can be localized in different locations along the field line.« less

  4. Production of porous Calcium Phosphate (CaP) ceramics with aligned pores using ceramic/camphene-based co-extrusion.

    PubMed

    Choi, Won-Young; Kim, Hyoun-Ee; Moon, Young-Wook; Shin, Kwan-Ha; Koh, Young-Hag

    2015-01-01

    Calcium phosphate (CaP) ceramics are one of the most valuable biomaterials for uses as the bone scaffold owing to their outstanding biocompatability, bioactivity, and biodegradation nature. In particular, these materials with an open porous structure can stimulate bone ingrowth into their 3-dimensionally interconnected pores. However, the creation of pores in bulk materials would inevitably cause a severe reduction in mechanical properties. Thus, it is a challenge to explore new ways of improving the mechanical properties of porous CaP scaffolds without scarifying their high porosity. Porous CaP ceramic scaffolds with aligned pores were successfully produced using ceramic/camphene-based co-extrusion. This aligned porous structure allowed for the achievement of high compressive strength when tested parallel to the direction of aligned pores. In addition, the overall porosity and mechanical properties of the aligned porous CaP ceramic scaffolds could be tailored simply by adjusting the initial CaP content in the CaP/camphene slurry. The porous CaP scaffolds showed excellent in vitro biocompatibility, suggesting their potential as the bone scaffold. Aligned porous CaP ceramic scaffolds with considerably enhanced mechanical properties and tailorable porosity would find very useful applications as the bone scaffold.

  5. Pathways toward unidirectional alignment in block copolymer thin films on faceted surfaces

    NASA Astrophysics Data System (ADS)

    Gunkel, Ilja; Gu, Xiaodan; Sarje, Abhinav; Hexemer, Alexander; Russell, Thomas

    2015-03-01

    Solvent vapor annealing (SVA) has been shown recently to be an effective means to produce long-range lateral order in block copolymer (BCP) thin films in relatively short times. Furthermore, using substrates with faceted surfaces allows for generating unidirectionally aligned BCP microdomains on the size scale of an entire wafer. While in recent years SVA has been largely demystified, the detailed pathways toward obtaining unidirectional alignment still remain unclear. Grazing-incidence X-ray scattering (GISAXS) is a very powerful tool for characterizing the structure and morphology of BCPs in thin films, and is particularly useful for studying structural changes in BCP thin films during SVA. We here present in situ GISAXS experiments on cylinder-forming PS-b-P2VP BCP thin films on faceted Sapphire substrates during annealing in THF. We show that the degree of alignment of cylindrical microdomains is greatly enhanced at solvent concentrations close to the order-disorder transition of the copolymer. Furthermore, we observed that inducing disorder by further increasing the solvent concentration and subsequent quenching to the ordered (not yet glassy) state induced the highest degree of alignment with nearly unidirectional alignment of the microdomains in less than 30 min.

  6. Imitating intrinsic alignments: a bias to the CMB lensing-galaxy shape cross-correlation power spectrum induced by the large-scale structure bispectrum

    NASA Astrophysics Data System (ADS)

    Merkel, Philipp M.; Schäfer, Björn Malte

    2017-10-01

    Cross-correlating the lensing signals of galaxies and comic microwave background (CMB) fluctuations is expected to provide valuable cosmological information. In particular, it may help tighten constraints on parameters describing the properties of intrinsically aligned galaxies at high redshift. To access the information conveyed by the cross-correlation signal, its accurate theoretical description is required. We compute the bias to CMB lensing-galaxy shape cross-correlation measurements induced by non-linear structure growth. Using tree-level perturbation theory for the large-scale structure bispectrum, we find that the bias is negative on most angular scales, therefore mimicking the signal of intrinsic alignments. Combining Euclid-like galaxy lensing data with a CMB experiment comparable to the Planck satellite mission, the bias becomes significant only on smallest scales (ℓ ≳ 2500). For improved CMB observations, however, the corrections amount to 10-15 per cent of the CMB lensing-intrinsic alignment signal over a wide multipole range (10 ≲ ℓ ≲ 2000). Accordingly, the power spectrum bias, if uncorrected, translates into 2σ and 3σ errors in the determination of the intrinsic alignment amplitude in the case of CMB stage III and stage IV experiments, respectively.

  7. Assessing the relevance of higher education courses.

    PubMed

    Gómez, Pedro; González, María Jose; Gil, Francisco; Lupiáñez, José Luis; Moreno, María Francisca; Rico, Luis; Romero, Isabel

    2007-05-01

    The establishment of the European Higher Education Area has involved specifying lists of professional competencies that programs are expected to develop, and with this the need for procedures to measure how every course within a higher education program is aligned with the program's competencies. We propose an instrument for characterizing this alignment, a process that we call assessing the relevance of a course. Using information from the course syllabus (objectives, contents and assessment scheme), our instrument produces indicators for characterizing the syllabus in terms of a competence list and for assessing its coherence. Because assessment involves quality, the results obtained can also be used to revise and improve the course syllabus. We illustrate this process with an example of a methods course from a mathematics teacher education program at a Spanish university.

  8. Taking Stock of Parent Education in the Family Courts: Envisioning a Public Health Model

    PubMed Central

    Salem, Peter; Sandler, Irwin; Wolchik, Sharlene

    2012-01-01

    The paper reviewed the development and current status of the parent education movement in the Family Courts. Parent education programs are now being implemented in courts throughout the United States and have a high level of public acceptance; however, a stronger research methodology to evaluate the effects and continued work to align the goals with the content and teaching strategies of these programs are needed. A new conceptual framework is proposed for parent education, which views divorce as a public health problem for children as well as a legal issue. The three-level framework uses concepts from public health to align the goals, content and format of parent education programs and to enable rigorous evaluations of the outcomes achieved by these programs. PMID:23641191

  9. Induction and quantification of collagen fiber alignment in a three-dimensional hydroxyapatite-collagen composite scaffold.

    PubMed

    Banglmaier, Richard F; Sander, Edward A; VandeVord, Pamela J

    2015-04-01

    Hydroxyapatite-collagen composite scaffolds are designed to serve as a regenerative load bearing replacement that mimics bone. However, the material properties of these scaffolds are at least an order of magnitude less than that of bone and subject to fail under physiological loading conditions. These scaffolds compositionally resemble bone but they do not possess important structural attributes such as an ordered arrangement of collagen fibers, which is a correlate to the mechanical properties in bone. Furthermore, it is unclear how much ordering of structure is satisfactory to mimic bone. Therefore, quantitative methods are needed to characterize collagen fiber alignment in these scaffolds for better correlation between the scaffold structure and the mechanical properties. A combination of extrusion and compaction was used to induce collagen fiber alignment in composite scaffolds. Collagen fiber alignment, due to extrusion and compaction, was quantified from polarized light microscopy images with a Fourier transform image processing algorithm. The Fourier transform method was capable of resolving the degree of collagen alignment from polarized light images. Anisotropy indices of the image planes ranged from 0.08 to 0.45. Increases in the degree of fiber alignment induced solely by extrusion (0.08-0.25) or compaction (0.25-0.44) were not as great as those by the combination of extrusion and compaction (0.35-0.45). Additional measures of randomness and fiber direction corroborate these anisotropy findings. This increased degree of collagen fiber alignment was induced in a preferred direction that is consistent with the extrusion direction and parallel with the compacted plane. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  10. Genetic algorithms for protein threading.

    PubMed

    Yadgari, J; Amir, A; Unger, R

    1998-01-01

    Despite many years of efforts, a direct prediction of protein structure from sequence is still not possible. As a result, in the last few years researchers have started to address the "inverse folding problem": Identifying and aligning a sequence to the fold with which it is most compatible, a process known as "threading". In two meetings in which protein folding predictions were objectively evaluated, it became clear that threading as a concept promises a real breakthrough, but that much improvement is still needed in the technique itself. Threading is a NP-hard problem, and thus no general polynomial solution can be expected. Still a practical approach with demonstrated ability to find optimal solutions in many cases, and acceptable solutions in other cases, is needed. We applied the technique of Genetic Algorithms in order to significantly improve the ability of threading algorithms to find the optimal alignment of a sequence to a structure, i.e. the alignment with the minimum free energy. A major progress reported here is the design of a representation of the threading alignment as a string of fixed length. With this representation validation of alignments and genetic operators are effectively implemented. Appropriate data structure and parameters have been selected. It is shown that Genetic Algorithm threading is effective and is able to find the optimal alignment in a few test cases. Furthermore, the described algorithm is shown to perform well even without pre-definition of core elements. Existing threading methods are dependent on such constraints to make their calculations feasible. But the concept of core elements is inherently arbitrary and should be avoided if possible. While a rigorous proof is hard to submit yet an, we present indications that indeed Genetic Algorithm threading is capable of finding consistently good solutions of full alignments in search spaces of size up to 10(70).

  11. SP-Designer: a user-friendly program for designing species-specific primer pairs from DNA sequence alignments.

    PubMed

    Villard, Pierre; Malausa, Thibaut

    2013-07-01

    SP-Designer is an open-source program providing a user-friendly tool for the design of specific PCR primer pairs from a DNA sequence alignment containing sequences from various taxa. SP-Designer selects PCR primer pairs for the amplification of DNA from a target species on the basis of several criteria: (i) primer specificity, as assessed by interspecific sequence polymorphism in the annealing regions, (ii) the biochemical characteristics of the primers and (iii) the intended PCR conditions. SP-Designer generates tables, detailing the primer pair and PCR characteristics, and a FASTA file locating the primer sequences in the original sequence alignment. SP-Designer is Windows-compatible and freely available from http://www2.sophia.inra.fr/urih/sophia_mart/sp_designer/info_sp_designer.php. © 2013 John Wiley & Sons Ltd.

  12. SPARSE: quadratic time simultaneous alignment and folding of RNAs without sequence-based heuristics.

    PubMed

    Will, Sebastian; Otto, Christina; Miladi, Milad; Möhl, Mathias; Backofen, Rolf

    2015-08-01

    RNA-Seq experiments have revealed a multitude of novel ncRNAs. The gold standard for their analysis based on simultaneous alignment and folding suffers from extreme time complexity of [Formula: see text]. Subsequently, numerous faster 'Sankoff-style' approaches have been suggested. Commonly, the performance of such methods relies on sequence-based heuristics that restrict the search space to optimal or near-optimal sequence alignments; however, the accuracy of sequence-based methods breaks down for RNAs with sequence identities below 60%. Alignment approaches like LocARNA that do not require sequence-based heuristics, have been limited to high complexity ([Formula: see text] quartic time). Breaking this barrier, we introduce the novel Sankoff-style algorithm 'sparsified prediction and alignment of RNAs based on their structure ensembles (SPARSE)', which runs in quadratic time without sequence-based heuristics. To achieve this low complexity, on par with sequence alignment algorithms, SPARSE features strong sparsification based on structural properties of the RNA ensembles. Following PMcomp, SPARSE gains further speed-up from lightweight energy computation. Although all existing lightweight Sankoff-style methods restrict Sankoff's original model by disallowing loop deletions and insertions, SPARSE transfers the Sankoff algorithm to the lightweight energy model completely for the first time. Compared with LocARNA, SPARSE achieves similar alignment and better folding quality in significantly less time (speedup: 3.7). At similar run-time, it aligns low sequence identity instances substantially more accurate than RAF, which uses sequence-based heuristics. © The Author 2015. Published by Oxford University Press.

  13. A practical strategy for the accurate measurement of residual dipolar couplings in strongly aligned small molecules

    NASA Astrophysics Data System (ADS)

    Liu, Yizhou; Cohen, Ryan D.; Martin, Gary E.; Williamson, R. Thomas

    2018-06-01

    Accurate measurement of residual dipolar couplings (RDCs) requires an appropriate degree of alignment in order to optimize data quality. An overly weak alignment yields very small anisotropic data that are susceptible to measurement errors, whereas an overly strong alignment introduces extensive anisotropic effects that severely degrade spectral quality. The ideal alignment amplitude also depends on the specific pulse sequence used for the coupling measurement. In this work, we introduce a practical strategy for the accurate measurement of one-bond 13C-1H RDCs up to a range of ca. -300 to +300 Hz, corresponding to an alignment that is an order of magnitude stronger than typically employed for small molecule structural elucidation. This strong alignment was generated in the mesophase of the commercially available poly-γ-(benzyl-L-glutamate) polymer. The total coupling was measured by the simple and well-studied heteronuclear two-dimensional J-resolved experiment, which performs well in the presence of strong anisotropic effects. In order to unequivocally determine the sign of the total coupling and resolve ambiguities in assigning total couplings in the CH2 group, coupling measurements were conducted at an isotropic condition plus two anisotropic conditions of different alignment amplitudes. Most RDCs could be readily extracted from these measurements whereas more complicated spectral effects resulting from strong homonuclear coupling could be interpreted either theoretically or by simulation. Importantly, measurement of these very large RDCs actually offers significantly improved data quality and utility for the structure determination of small organic molecules.

  14. Examining Alignment between State Performance Assessment and Mathematics Classroom Activities

    ERIC Educational Resources Information Center

    Parke, Carol S.; Lane, Suzanne

    2008-01-01

    The authors describe research on the extent to which mathematics classroom activities in Maryland were aligned with Maryland learning outcomes and the Maryland School Performance Assessment Program (MSPAP; Maryland State Department of Education, 1995, 2000). The study was part of a larger research project (S. Lane, C. S. Parke, & C. A. Stone,…

  15. Aligning English Language Testing with Curriculum

    ERIC Educational Resources Information Center

    Palacio, Marcela; Gaviria, Sandra; Brown, James Dean

    2016-01-01

    Frustrations with traditional testing led a group of teachers at the English for adults program at Universidad EAFIT (Colombia) to design tests aligned with the institutional teaching philosophy and classroom practices. This article reports on a study of an item-by-item evaluation of a series of English exams for validity and reliability in an…

  16. CTE Alignment with 21st Century Skills

    ERIC Educational Resources Information Center

    Drysielski, Robert

    2015-01-01

    Career and technical education generally has focused on helping people to understand the relationship between education and work to acquire employment skills. There is a need for action to ensure that the programs being offered in Career and Technical Education (CTE) align with the needs of the 21st century workforce. This research will attempted…

  17. Getting What They Want: Aligning Student Expectations of Advising with Perceived Advisor Behaviors

    ERIC Educational Resources Information Center

    Anderson, Whitney; Motto, Justin S.; Bourdeaux, Renee

    2014-01-01

    Maintaining effective undergraduate academic advising programs that meet the needs of students is an ongoing challenge for universities across the country. Using expectancy violations theory as a lens, this study argues that student satisfaction with advising is linked to alignment between student expectations of the advising process and perceived…

  18. People Strategy in Human Resources: Lessons for Mentoring in Higher Education

    ERIC Educational Resources Information Center

    Baker, Vicki L.

    2015-01-01

    In this article, I offer the notion of alignment, a human resources framework, as a conceptual tool for better informing the development of mentoring programming and policy in higher education. Alignment accounts for both individual and organizational factors as means for providing the necessary connections among human resources and organizational…

  19. SEAN: SNP prediction and display program utilizing EST sequence clusters.

    PubMed

    Huntley, Derek; Baldo, Angela; Johri, Saurabh; Sergot, Marek

    2006-02-15

    SEAN is an application that predicts single nucleotide polymorphisms (SNPs) using multiple sequence alignments produced from expressed sequence tag (EST) clusters. The algorithm uses rules of sequence identity and SNP abundance to determine the quality of the prediction. A Java viewer is provided to display the EST alignments and predicted SNPs.

  20. Log-odds sequence logos

    PubMed Central

    Yu, Yi-Kuo; Capra, John A.; Stojmirović, Aleksandar; Landsman, David; Altschul, Stephen F.

    2015-01-01

    Motivation: DNA and protein patterns are usefully represented by sequence logos. However, the methods for logo generation in common use lack a proper statistical basis, and are non-optimal for recognizing functionally relevant alignment columns. Results: We redefine the information at a logo position as a per-observation multiple alignment log-odds score. Such scores are positive or negative, depending on whether a column’s observations are better explained as arising from relatedness or chance. Within this framework, we propose distinct normalized maximum likelihood and Bayesian measures of column information. We illustrate these measures on High Mobility Group B (HMGB) box proteins and a dataset of enzyme alignments. Particularly in the context of protein alignments, our measures improve the discrimination of biologically relevant positions. Availability and implementation: Our new measures are implemented in an open-source Web-based logo generation program, which is available at http://www.ncbi.nlm.nih.gov/CBBresearch/Yu/logoddslogo/index.html. A stand-alone version of the program is also available from this site. Contact: altschul@ncbi.nlm.nih.gov Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25294922

  1. Evolutionary profiles derived from the QR factorization of multiple structural alignments gives an economy of information.

    PubMed

    O'Donoghue, Patrick; Luthey-Schulten, Zaida

    2005-02-25

    We present a new algorithm, based on the multidimensional QR factorization, to remove redundancy from a multiple structural alignment by choosing representative protein structures that best preserve the phylogenetic tree topology of the homologous group. The classical QR factorization with pivoting, developed as a fast numerical solution to eigenvalue and linear least-squares problems of the form Ax=b, was designed to re-order the columns of A by increasing linear dependence. Removing the most linear dependent columns from A leads to the formation of a minimal basis set which well spans the phase space of the problem at hand. By recasting the problem of redundancy in multiple structural alignments into this framework, in which the matrix A now describes the multiple alignment, we adapted the QR factorization to produce a minimal basis set of protein structures which best spans the evolutionary (phase) space. The non-redundant and representative profiles obtained from this procedure, termed evolutionary profiles, are shown in initial results to outperform well-tested profiles in homology detection searches over a large sequence database. A measure of structural similarity between homologous proteins, Q(H), is presented. By properly accounting for the effect and presence of gaps, a phylogenetic tree computed using this metric is shown to be congruent with the maximum-likelihood sequence-based phylogeny. The results indicate that evolutionary information is indeed recoverable from the comparative analysis of protein structure alone. Applications of the QR ordering and this structural similarity metric to analyze the evolution of structure among key, universally distributed proteins involved in translation, and to the selection of representatives from an ensemble of NMR structures are also discussed.

  2. Measuring the Implementation Fidelity of Student Affairs Programs: A Critical Component of the Outcomes Assessment Cycle

    ERIC Educational Resources Information Center

    Gerstner, Jerusha J.; Finney, Sara J.

    2013-01-01

    Implementation fidelity assessment provides a means of measuring the alignment between the planned program and the implemented program. Unfortunately, the implemented program can differ from the planned program, resulting in ambiguous inferences about the planned program's effectiveness (i.e., it is uncertain if poor results are due to an…

  3. ARYANA: Aligning Reads by Yet Another Approach

    PubMed Central

    2014-01-01

    Motivation Although there are many different algorithms and software tools for aligning sequencing reads, fast gapped sequence search is far from solved. Strong interest in fast alignment is best reflected in the $106 prize for the Innocentive competition on aligning a collection of reads to a given database of reference genomes. In addition, de novo assembly of next-generation sequencing long reads requires fast overlap-layout-concensus algorithms which depend on fast and accurate alignment. Contribution We introduce ARYANA, a fast gapped read aligner, developed on the base of BWA indexing infrastructure with a completely new alignment engine that makes it significantly faster than three other aligners: Bowtie2, BWA and SeqAlto, with comparable generality and accuracy. Instead of the time-consuming backtracking procedures for handling mismatches, ARYANA comes with the seed-and-extend algorithmic framework and a significantly improved efficiency by integrating novel algorithmic techniques including dynamic seed selection, bidirectional seed extension, reset-free hash tables, and gap-filling dynamic programming. As the read length increases ARYANA's superiority in terms of speed and alignment rate becomes more evident. This is in perfect harmony with the read length trend as the sequencing technologies evolve. The algorithmic platform of ARYANA makes it easy to develop mission-specific aligners for other applications using ARYANA engine. Availability ARYANA with complete source code can be obtained from http://github.com/aryana-aligner PMID:25252881

  4. BigFoot: Bayesian alignment and phylogenetic footprinting with MCMC

    PubMed Central

    Satija, Rahul; Novák, Ádám; Miklós, István; Lyngsø, Rune; Hein, Jotun

    2009-01-01

    Background We have previously combined statistical alignment and phylogenetic footprinting to detect conserved functional elements without assuming a fixed alignment. Considering a probability-weighted distribution of alignments removes sensitivity to alignment errors, properly accommodates regions of alignment uncertainty, and increases the accuracy of functional element prediction. Our method utilized standard dynamic programming hidden markov model algorithms to analyze up to four sequences. Results We present a novel approach, implemented in the software package BigFoot, for performing phylogenetic footprinting on greater numbers of sequences. We have developed a Markov chain Monte Carlo (MCMC) approach which samples both sequence alignments and locations of slowly evolving regions. We implement our method as an extension of the existing StatAlign software package and test it on well-annotated regions controlling the expression of the even-skipped gene in Drosophila and the α-globin gene in vertebrates. The results exhibit how adding additional sequences to the analysis has the potential to improve the accuracy of functional predictions, and demonstrate how BigFoot outperforms existing alignment-based phylogenetic footprinting techniques. Conclusion BigFoot extends a combined alignment and phylogenetic footprinting approach to analyze larger amounts of sequence data using MCMC. Our approach is robust to alignment error and uncertainty and can be applied to a variety of biological datasets. The source code and documentation are publicly available for download from PMID:19715598

  5. BigFoot: Bayesian alignment and phylogenetic footprinting with MCMC.

    PubMed

    Satija, Rahul; Novák, Adám; Miklós, István; Lyngsø, Rune; Hein, Jotun

    2009-08-28

    We have previously combined statistical alignment and phylogenetic footprinting to detect conserved functional elements without assuming a fixed alignment. Considering a probability-weighted distribution of alignments removes sensitivity to alignment errors, properly accommodates regions of alignment uncertainty, and increases the accuracy of functional element prediction. Our method utilized standard dynamic programming hidden markov model algorithms to analyze up to four sequences. We present a novel approach, implemented in the software package BigFoot, for performing phylogenetic footprinting on greater numbers of sequences. We have developed a Markov chain Monte Carlo (MCMC) approach which samples both sequence alignments and locations of slowly evolving regions. We implement our method as an extension of the existing StatAlign software package and test it on well-annotated regions controlling the expression of the even-skipped gene in Drosophila and the alpha-globin gene in vertebrates. The results exhibit how adding additional sequences to the analysis has the potential to improve the accuracy of functional predictions, and demonstrate how BigFoot outperforms existing alignment-based phylogenetic footprinting techniques. BigFoot extends a combined alignment and phylogenetic footprinting approach to analyze larger amounts of sequence data using MCMC. Our approach is robust to alignment error and uncertainty and can be applied to a variety of biological datasets. The source code and documentation are publicly available for download from http://www.stats.ox.ac.uk/~satija/BigFoot/

  6. ARYANA: Aligning Reads by Yet Another Approach.

    PubMed

    Gholami, Milad; Arbabi, Aryan; Sharifi-Zarchi, Ali; Chitsaz, Hamidreza; Sadeghi, Mehdi

    2014-01-01

    Although there are many different algorithms and software tools for aligning sequencing reads, fast gapped sequence search is far from solved. Strong interest in fast alignment is best reflected in the $10(6) prize for the Innocentive competition on aligning a collection of reads to a given database of reference genomes. In addition, de novo assembly of next-generation sequencing long reads requires fast overlap-layout-concensus algorithms which depend on fast and accurate alignment. We introduce ARYANA, a fast gapped read aligner, developed on the base of BWA indexing infrastructure with a completely new alignment engine that makes it significantly faster than three other aligners: Bowtie2, BWA and SeqAlto, with comparable generality and accuracy. Instead of the time-consuming backtracking procedures for handling mismatches, ARYANA comes with the seed-and-extend algorithmic framework and a significantly improved efficiency by integrating novel algorithmic techniques including dynamic seed selection, bidirectional seed extension, reset-free hash tables, and gap-filling dynamic programming. As the read length increases ARYANA's superiority in terms of speed and alignment rate becomes more evident. This is in perfect harmony with the read length trend as the sequencing technologies evolve. The algorithmic platform of ARYANA makes it easy to develop mission-specific aligners for other applications using ARYANA engine. ARYANA with complete source code can be obtained from http://github.com/aryana-aligner.

  7. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Nowak, Maria; Eichorn, William; Hill, Michael; Hylan, Jason; Marsh, James; Ohl, Raymond; Sampler, Henry; Wright, Geraldine; Crane, Allen; Herrera, Acey; hide

    2007-01-01

    The James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (approx.40K). The JWST Observatory architecture includes the Optical Telescope Element and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI) including a Guider. The ISIM optical metering structure is a roughly 2.2x1.7x2.2mY, asymmetric frame that is composed of carbon fiber and resin tubes bonded to invar end fittings and composite gussets and clips. The structure supports the SIs, isolates the SIs from the OTE, and supports thermal and electrical subsystems. The structure is attached to the OTE structure via strut-like kinematic mounts. The ISM structure must meet its requirements at the approx.40K cryogenic operating temperature. The SIs are aligned to the structure s coordinate system under ambient, clean room conditions using laser tracker and theodolite metrology. The ISM structure is thermally cycled for stress relief and in order to measure temperature-induced mechanical, structural changes. These ambient-to-cryogenic changes in the alignment of SI and OTE-related interfaces are an important component in the JWST Observatory alignment plan and must be verified.

  8. Mental health education in occupational therapy professional preparation programs: Alignment between clinician priorities and coverage in university curricula.

    PubMed

    Scanlan, Justin Newton; Meredith, Pamela J; Haracz, Kirsti; Ennals, Priscilla; Pépin, Geneviève; Webster, Jayne S; Arblaster, Karen; Wright, Shelley

    2017-12-01

    Occupational therapy programs must prepare graduates for work in mental health. However, this area of practice is complex and rapidly changing. This study explored the alignment between educational priorities identified by occupational therapists practising in mental health and level of coverage of these topics in occupational therapy programs in Australia and New Zealand. Surveys were distributed to heads of all occupational therapy programs across Australia and New Zealand. The survey included educational priorities identified by occupational therapists in mental health from a previous study. Respondents were requested to identify the level of coverage given to each of these priorities within their curriculum. These data were analysed to determine a ranking of educational topics in terms of level of coverage in university programs. Responses were received for 19 programs from 16 universities. Thirty-four topics were given 'High-level coverage' in university programs, and these were compared against the 29 topics classified as 'Essential priorities' by clinicians. Twenty topics were included in both the 'Essential priorities' and 'High-level coverage' categories. Topics considered to be 'Essential priorities' by clinicians which were not given 'High-level coverage' in university programs included the following: mental health fieldwork experiences; risk assessment and management; professional self-care resilience and sensory approaches. While there appears to be overall good alignment between mental health curricula and priorities identified by practising occupational therapists, there are some discrepancies. These discrepancies are described and establish a strong foundation for further discussion between clinicians, academics and university administration to support curriculum review and revision. © 2017 Occupational Therapy Australia.

  9. The NCI Community Oncology Research Program: what every clinician needs to know.

    PubMed

    McCaskill-Stevens, Worta; Lyss, Alan P; Good, Marge; Marsland, Thomas; Lilenbaum, Rogerio

    2013-01-01

    Research in the community setting is essential for the translation of advances in cancer research into practice and improving cancer care for all populations. The National Cancer Institute is proposing a new community-based program, NCI Community Oncology Research Program (NCORP), which is the alignment of two existing programs, the Community Clinical Oncology Program, Minority-Based Community Clinical Oncology Program, and their Research Bases, and the National Cancer Institute's Community Cancer Centers Program. NCROP will support cancer control, prevention, treatment, and screening clinical trials and expand its research scope to include cancer care delivery research. Cancer disparities research will be integrated into studies across the continuum of NCORP research. Input from current NCI-funded community investigators provides critical insight into the challenges faced by oncology practices within various organizational structures. Furthermore, these investigators identify the resources, both administrative and clinical, that will be required in the community setting to support cancer care delivery research and to meet the requirements for a new generation of clinical research. The American Society for Clinical Oncology (ASCO) has initiated a forum to focus on the conduct of clinical research in the community setting. Resources are being developed to help practices in managing cancer care in community settings.

  10. Protein structure-structure alignment with discrete Fréchet distance.

    PubMed

    Jiang, Minghui; Xu, Ying; Zhu, Binhai

    2008-02-01

    Matching two geometric objects in two-dimensional (2D) and three-dimensional (3D) spaces is a central problem in computer vision, pattern recognition, and protein structure prediction. In particular, the problem of aligning two polygonal chains under translation and rotation to minimize their distance has been studied using various distance measures. It is well known that the Hausdorff distance is useful for matching two point sets, and that the Fréchet distance is a superior measure for matching two polygonal chains. The discrete Fréchet distance closely approximates the (continuous) Fréchet distance, and is a natural measure for the geometric similarity of the folded 3D structures of biomolecules such as proteins. In this paper, we present new algorithms for matching two polygonal chains in two dimensions to minimize their discrete Fréchet distance under translation and rotation, and an effective heuristic for matching two polygonal chains in three dimensions. We also describe our empirical results on the application of the discrete Fréchet distance to protein structure-structure alignment.

  11. Hazardous Materials Emergency Preparedness grants program : assessment of the alignment between local activities and program goals

    DOT National Transportation Integrated Search

    2005-10-01

    This report has been commissioned as a first step in determining the extent of the links between the HMEP Grants Program and the DOT hazardous materials program, and in identifying opportunities to strengthen these links. It presents findings from an...

  12. Laser program annual report, 1977. Volume 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bender, C.F.; Jarman, B.D.

    1978-07-01

    An overview is given of the laser fusion program. The solid-state program covers the Shiva and Nova projects. Laser components, control systems, alignment systems, laser beam diagnostics, power conditioning, and optical components are described. The fusion experimental program concerns the diagnostics and data acquisition associated with Argus and Shiva. (MOW)

  13. How the EWD Program Aims to Meet Workforce Needs. Policy Brief

    ERIC Educational Resources Information Center

    Jez, Su Jin; Nodine, Thad

    2016-01-01

    The Economic and Workforce Development Program (EWD) aims to support California's economy by aligning community college educational programs with workforce development needs. The program connects employers and community college educators through a network of workforce training resources and partnerships called "Doing What Matters for Jobs and…

  14. Ultrasonic alignment of microparticles in nozzle-like geometries

    NASA Astrophysics Data System (ADS)

    Whittaker, Molly A.; Dauson, Erin R.; Parra-Raad, Jaime; Heard, Robert A.; Oppenheim, Irving J.

    2018-03-01

    Additive manufacturing (3-D printing) is presently limited by the mechanical properties of the materials, such as polymer resins, that are otherwise efficient and economical for part-forming. Reinforcing the resin with microscale fibers and/or particles would be an effective mechanism to achieve desired mechanical properties such as strength and ductility. Our work combines standing wave ultrasonics and microfluidics to align microparticles in devices that can act as print nozzles, based in part on our prior work with cell sorting. In this paper three different approaches are presented illustrating different engineering tradeoffs, and demonstrating laboratory results of particle alignment. First acoustic resonators are discussed, in which the ultrasonic standing waves result mostly from the mechanical properties of the microfluidic structure, excited by a piezoceramic transducer. Next non-resonant microfluidic structures are discussed, in which ultrasonic standing waves are produced directly by symmetrical transducer deployment. Finally, devices that combine nozzle-like structures, which themselves are suitable acoustic resonators, subjected to symmetrical ultrasonic excitation are presented. We will show that all three configurations will align microparticles, and discuss the tradeoffs among them for subsequent configuration of a print nozzle.

  15. Complexity: an internet resource for analysis of DNA sequence complexity

    PubMed Central

    Orlov, Y. L.; Potapov, V. N.

    2004-01-01

    The search for DNA regions with low complexity is one of the pivotal tasks of modern structural analysis of complete genomes. The low complexity may be preconditioned by strong inequality in nucleotide content (biased composition), by tandem or dispersed repeats or by palindrome-hairpin structures, as well as by a combination of all these factors. Several numerical measures of textual complexity, including combinatorial and linguistic ones, together with complexity estimation using a modified Lempel–Ziv algorithm, have been implemented in a software tool called ‘Complexity’ (http://wwwmgs.bionet.nsc.ru/mgs/programs/low_complexity/). The software enables a user to search for low-complexity regions in long sequences, e.g. complete bacterial genomes or eukaryotic chromosomes. In addition, it estimates the complexity of groups of aligned sequences. PMID:15215465

  16. Aligned Single Wall Carbon Nanotube Polymer Composites Using an Electric Field

    NASA Technical Reports Server (NTRS)

    Park, Cheol; Wiklinson, John; Banda, Sumanth; Ounaies, Zoubeida; Wise, Kristopher E.; Sauti, Godfrey; Lillehei, Peter T.; Harrison, Joycelyn S.

    2005-01-01

    While high shear alignment has been shown to improve the mechanical properties of single wall carbon nanotubes (SWNT)-polymer composites, it is difficult to control and often results in degradation of the electrical and dielectric properties of the composite. Here, we report a novel method to actively align SWNTs in a polymer matrix, which allows for control over the degree of alignment of SWNTs without the side effects of shear alignment. In this process, SWNTs are aligned via field-induced dipolar interactions among the nanotubes under an AC electric field in a liquid matrix followed by immobilization by photopolymerization while maintaining the electric field. Alignment of SWNTs was controlled as a function of magnitude, frequency, and application time of the applied electric field. The degree of SWNT alignment was assessed using optical microscopy and polarized Raman spectroscopy and the morphology of the aligned nanocomposites was investigated by high resolution scanning electron microscopy. The structure of the field induced aligned SWNTs is intrinsically different from that of shear aligned SWNTs. In the present work, SWNTs are not only aligned along the field, but also migrate laterally to form thick, aligned SWNT percolative columns between the electrodes. The actively aligned SWNTs amplify the electrical and dielectric properties in addition to improving the mechanical properties of the composite. All of these properties of the aligned nanocomposites exhibited anisotropic characteristics, which were controllable by tuning the applied field conditions.

  17. AGScan: a pluggable microarray image quantification software based on the ImageJ library.

    PubMed

    Cathelin, R; Lopez, F; Klopp, Ch

    2007-01-15

    Many different programs are available to analyze microarray images. Most programs are commercial packages, some are free. In the latter group only few propose automatic grid alignment and batch mode. More often than not a program implements only one quantification algorithm. AGScan is an open source program that works on all major platforms. It is based on the ImageJ library [Rasband (1997-2006)] and offers a plug-in extension system to add new functions to manipulate images, align grid and quantify spots. It is appropriate for daily laboratory use and also as a framework for new algorithms. The program is freely distributed under X11 Licence. The install instructions can be found in the user manual. The software can be downloaded from http://mulcyber.toulouse.inra.fr/projects/agscan/. The questions and plug-ins can be sent to the contact listed below.

  18. Inferences from structural comparison: flexibility, secondary structure wobble and sequence alignment optimization.

    PubMed

    Zhang, Gaihua; Su, Zhen

    2012-01-01

    Work on protein structure prediction is very useful in biological research. To evaluate their accuracy, experimental protein structures or their derived data are used as the 'gold standard'. However, as proteins are dynamic molecular machines with structural flexibility such a standard may be unreliable. To investigate the influence of the structure flexibility, we analysed 3,652 protein structures of 137 unique sequences from 24 protein families. The results showed that (1) the three-dimensional (3D) protein structures were not rigid: the root-mean-square deviation (RMSD) of the backbone Cα of structures with identical sequences was relatively large, with the average of the maximum RMSD from each of the 137 sequences being 1.06 Å; (2) the derived data of the 3D structure was not constant, e.g. the highest ratio of the secondary structure wobble site was 60.69%, with the sequence alignments from structural comparisons of two proteins in the same family sometimes being completely different. Proteins may have several stable conformations and the data derived from resolved structures as a 'gold standard' should be optimized before being utilized as criteria to evaluate the prediction methods, e.g. sequence alignment from structural comparison. Helix/β-sheet transition exists in normal free proteins. The coil ratio of the 3D structure could affect its resolution as determined by X-ray crystallography.

  19. Electronic properties of semiconductor-water interfaces: Predictions from ab-initio molecular dynamics and many-body perturbation theory

    NASA Astrophysics Data System (ADS)

    Pham, Tuan Anh

    2015-03-01

    Photoelectrochemical cells offer a promising avenue for hydrogen production from water and sunlight. The efficiency of these devices depends on the electronic structure of the interface between the photoelectrode and liquid water, including the alignment between the semiconductor band edges and the water redox potential. In this talk, we will present the results of first principles calculations of semiconductor-water interfaces that are obtained with a combination of density functional theory (DFT)-based molecular dynamics simulations and many-body perturbation theory (MBPT). First, we will discuss the development of an MBPT approach that is aimed at improving the efficiency and accuracy of existing methodologies while still being applicable to complex heterogeneous interfaces consisting of hundreds of atoms. We will then present studies of the electronic structure of liquid water and aqueous solutions using MBPT, which represent an essential step in establishing a quantitative framework for computing the energy alignment at semiconductor-water interfaces. Finally, using a combination of DFT-based molecular dynamics simulations and MBPT, we will describe the relationship between interfacial structure, electronic properties of semiconductors and their reactivity in aqueous solutions through a number of examples, including functionalized Si surfaces and GaP/InP surfaces in contact with liquid water. T.A.P was supported by the U.S. Department of Energy at the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and by the Lawrence Fellowship Program.

  20. An anisotropically and heterogeneously aligned patterned electrospun scaffold with tailored mechanical property and improved bioactivity for vascular tissue engineering.

    PubMed

    Xu, He; Li, Haiyan; Ke, Qinfei; Chang, Jiang

    2015-04-29

    The development of vascular scaffolds with controlled mechanical properties and stimulatory effects on biological activities of endothelial cells still remains a significant challenge to vascular tissue engineering. In this work, we reported an innovative approach to prepare a new type of vascular scaffolds with anisotropically and heterogeneously aligned patterns using electrospinning technique with unique wire spring templates, and further investigated the structural effects of the patterned electrospun scaffolds on mechanical properties and angiogenic differentiation of human umbilical vein endothelial cells (HUVECs). Results showed that anisotropically aligned patterned nanofibrous structure was obtained by depositing nanofibers on template in a structurally different manner, one part of nanofibers densely deposited on the embossments of wire spring and formed cylindrical-like structures in the transverse direction, while others loosely suspended and aligned along the longitudinal direction, forming a three-dimensional porous microstructure. We further found that such structures could efficiently control the mechanical properties of electrospun vascular scaffolds in both longitudinal and transverse directions by altering the interval distances between the embossments of patterned scaffolds. When HUVECs were cultured on scaffolds with different microstructures, the patterned scaffolds distinctively promoted adhesion of HUVECs at early stage and proliferation during the culture period. Most importantly, cells experienced a large shape change associated with cell cytoskeleton and nuclei remodeling, leading to a stimulatory effect on angiogenesis differentiation of HUVECs by the patterned microstructures of electrospun scaffolds, and the scaffolds with larger distances of intervals showed a higher stimulatory effect. These results suggest that electrospun scaffolds with the anisotropically and heterogeneously aligned patterns, which could efficiently control the mechanical properties and bioactivities of the scaffolds, might have great potential in vascular tissue engineering application.

  1. Disruption of sheet-like structures in Alfvénic turbulence by magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Mallet, A.; Schekochihin, A. A.; Chandran, B. D. G.

    2017-07-01

    We propose a mechanism whereby the intense, sheet-like structures naturally formed by dynamically aligning Alfvénic turbulence are destroyed by magnetic reconnection at a scale \\hat{λ }_D, larger than the dissipation scale predicted by models of intermittent, dynamically aligning turbulence. The reconnection process proceeds in several stages: first, a linear tearing mode with N magnetic islands grows and saturates, and then the X-points between these islands collapse into secondary current sheets, which then reconnect until the original structure is destroyed. This effectively imposes an upper limit on the anisotropy of the structures within the perpendicular plane, which means that at scale \\hat{λ }_D the turbulent dynamics change: at scales larger than \\hat{λ }_D, the turbulence exhibits scale-dependent dynamic alignment and a spectral index approximately equal to -3/2, while at scales smaller than \\hat{λ }_D, the turbulent structures undergo a succession of disruptions due to reconnection, limiting dynamic alignment, steepening the effective spectral index and changing the final dissipation scale. The scaling of \\hat{λ }_D with the Lundquist (magnetic Reynolds) number S_{L_\\perp } depends on the order of the statistics being considered, and on the specific model of intermittency; the transition between the two regimes in the energy spectrum is predicted at approximately \\hat{λ }_D˜ S_{L_\\perp }^{-0.6}. The spectral index below \\hat{λ }_D is bounded between -5/3 and -2.3. The final dissipation scale is at \\hat{λ }_{η ,∞}˜ S_{L_\\perp }^{-3/4}, the same as the Kolmogorov scale arising in theories of turbulence that do not involve scale-dependent dynamic alignment.

  2. Self-aligned gated field emission devices using single carbon nanofiber cathodes

    NASA Astrophysics Data System (ADS)

    Guillorn, M. A.; Melechko, A. V.; Merkulov, V. I.; Hensley, D. K.; Simpson, M. L.; Lowndes, D. H.

    2002-11-01

    We report on the fabrication and operation of integrated gated field emission devices using single vertically aligned carbon nanofiber (VACNF) cathodes where the gate aperture has been formed using a self-aligned technique based on chemical mechanical polishing. We find that this method for producing gated cathode devices easily achieves structures with gate apertures on the order of 2 mum that show good concentric alignment to the VACNF emitter. The operation of these devices was explored and field emission characteristics that fit well to the Fowler-Nordheim model of emission was demonstrated.

  3. Polarization-dependent DANES study on vertically-aligned ZnO nanorods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Chengjun; Park, Chang-In; Jin, Zhenlan

    2016-05-01

    The local structural and local density of states of vertically-aligned ZnO nanorods were examined by using a polarization-dependent diffraction anomalous near edge structure (DANES) measurements from c-oriented ZnO nanorods at the Zn K edge with the incident x-ray electric field parallel and perpendicular to the x-ray momentum transfer direction. Orientation-dependent local structures determined by DANES were comparable with polarization-dependent EXAFS results. Unlike other techniques, polarization-dependent DANES can uniquely describe the orientation-dependent local structural properties and the local density of states of a selected element in selected-phased crystals of compounds or mixed-phased structures.

  4. The current status and portability of our sequence handling software.

    PubMed Central

    Staden, R

    1986-01-01

    I describe the current status of our sequence analysis software. The package contains a comprehensive suite of programs for managing large shotgun sequencing projects, a program containing 61 functions for analysing single sequences and a program for comparing pairs of sequences for similarity. The programs that have been described before have been improved by the addition of new functions and by being made very much easier to use. The major interactive programs have 125 pages of online help available from within them. Several new programs are described including screen editing of aligned gel readings for shotgun sequencing projects; a method to highlight errors in aligned gel readings, new methods for searching for putative signals in sequences. We use the programs on a VAX computer but the whole package has been rewritten to make it easy to transport it to other machines. I believe the programs will now run on any machine with a FORTRAN77 compiler and sufficient memory. We are currently putting the programs onto an IBM PC XT/AT and another micro running under UNIX. PMID:3511446

  5. Key ingredients for implementing intensive outpatient programs within patient-centered medical homes: A literature review and qualitative analysis.

    PubMed

    Breland, Jessica Y; Asch, Steven M; Slightam, Cindie; Wong, Ava; Zulman, Donna M

    2016-03-01

    Intensive outpatient programs aim to transform care while conserving resources for high-need, high-cost patients, but little is known about factors that influence their implementation within patient-centered medical homes (PCMHs). In this mixed-methods study, we reviewed the literature to identify factors affecting intensive outpatient program implementation, then used semi-structured interviews to determine how these factors influenced the implementation of an intensive outpatient program within the Veterans Affairs' (VA) PCMH. Interviewees included facility leadership and clinical staff who were involved in a pilot Intensive Management Patient Aligned Care Team (ImPACT) intervention for high-need, high-cost VA PCMH patents. We classified implementation factors in the literature review and qualitative analysis using the Consolidated Framework for Implementation Research (CFIR). The literature review (n=9 studies) and analyses of interviews (n=15) revealed key implementation factors in three CFIR domains. First, the Inner Setting (i.e., the organizational and PCMH environment), mostly enabled implementation through a culture of innovation, good networks and communication, and positive tension for change. Second, Characteristics of Individuals, including creativity, flexibility, and interpersonal skills, allowed program staff to augment existing PCMH services. Finally, certain Intervention Characteristics (e.g., adaptability) enabled implementation, while others (e.g., complexity) generated implementation barriers. Resources and structural features common to PCMHs can facilitate implementation of intensive outpatient programs, but program success is also dependent on staff creativity and flexibility, and intervention adaptations to meet patient and organizational needs. Established PCMHs likely provide resources and environments that permit accelerated implementation of intensive outpatient programs. V. Published by Elsevier Inc.

  6. Dynamic trunk stabilization: a conceptual back injury prevention program for volleyball athletes.

    PubMed

    Smith, Chad E; Nyland, John; Caudill, Paul; Brosky, Joseph; Caborn, David N M

    2008-11-01

    The sport of volleyball creates considerable dynamic trunk stability demands. Back injury occurs all too frequently in volleyball, particularly among female athletes. The purpose of this clinical commentary is to review functional anatomy, muscle coactivation strategies, assessment of trunk muscle performance, and the characteristics of effective exercises for the trunk or core. From this information, a conceptual progressive 3-phase volleyball-specific training program is presented to improve dynamic trunk stability and to potentially reduce the incidence of back injury among volleyball athletes. Phase 1 addresses low-velocity motor control, kinesthetic awareness, and endurance, with the clinician providing cues to teach achievement of biomechanically neutral spine alignment. Phase 2 focuses on progressively higher velocity dynamic multiplanar endurance, coordination, and strength-power challenges integrating upper and lower extremity movements, while maintaining neutral spine alignment. Phase 3 integrates volleyball-specific skill simulations by breaking down composite movement patterns into their component parts, with differing dynamic trunk stability requirements, while maintaining neutral spine alignment. Prospective research is needed to validate the efficacy of this program.

  7. Alignment and position visualization methods for the biomedical imaging and therapy (BMIT) MRT lift

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bree, Michael, E-mail: michael.bree@lightsource.ca; Miller, Denise; Kerr, Graham

    The Microbeam Radiation Therapy (MRT) Lift is an eight stage positioning and scanning system at the Canadian Light Source’s BMIT Facility. Alignment of the sample with the beam using the MRT Lift is a time consuming and challenging task. The BMIT Group has developed a Python-based MRT Lift positioning and control program that uses a combination of computational and iterative methods to independently adjust the sample’s X, Y, Z, pitch and roll positions. The program offers “1-Click” alignment of the sample to the beam. Use of a wireframe visualization technique enables even minute movements to be illustrated. Proposed movements andmore » the resulting MRT Lift position can be manually verified before being applied. Optional integration with the SolidWorks modelling platform allows high quality renderings of the MRT Lift in its current or proposed position to be displayed in real time. Human factors principles are incorporated into the program with the objective of delivering easy to use controls for this complex device.« less

  8. 2017 Brownfields Federal Programs Guide

    EPA Pesticide Factsheets

    This document illustrates how the Brownfields Program does more than address environmental contamination—it recognizes a community’s quality of life aligning with economic development and sustainability, and looks to the future for revitalization.

  9. SU-F-J-44: Development of a Room Laser Based Real-Time Alignment Monitoring System Using An Array of Photodiodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Noh, Y; Kim, T; Kang, S

    2016-06-15

    Purpose: To develop a real-time alignment monitoring system (RAMS) to compensate for the limitations of the conventional room laser based alignment system, and to verify the feasibility of the RAMS. Methods: The RAMS was composed of a room laser sensing array (RLSA), an analog-todigital converter, and a control PC. In the RLSA, seven photodiodes (each in 1 mm width) are arranged in a pattern that the RAMS provides alignment in 1 mm resolution. It works based on detecting laser light aligned on one of photodiodes. When misaligned, the laser would match with different photodiode(s) giving signal at unexpected location. Thus,more » how much displaced can be determined. To verify the reproducibility of the system with respect to time as well as repeated set-ups, temporal reproducibility and repeatability test was conducted. The accuracy of the system was tested by obtaining detection signals with varying laser-match positions. Results: The signal of the RAMS was found to be stable with respect to time. The repeatability test resulted in a maximum coefficient of variance of 1.14%, suggesting that the signal of the RAMS was stable over repeated set-ups. In the accuracy test, signals between when the laser was aligned and notaligned with any of sensors could be distinguished by signal intensity. The signals of not-aligned sensors were always below 75% of the signal of the aligned sensor. It was confirmed that the system could detect 1 mm of movement by monitoring the pattern of signals, and could observe the movement of the system in real-time. Conclusion: We developed a room laser based alignment monitoring system. The feasibility test verified that the system is capable of quantitative alignment monitoring in real time. The system is relatively simple, not expensive, and considered to be easily incorporated into conventional room laser systems for real-time alignment monitoring. This research was supported by the Mid-career Researcher Program through NRF funded by the Ministry of Science, ICT & Future Planning of Korea (NRF-2014R1A2A1A10050270) and by the Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (No. 2013M2A2A7038291)« less

  10. Local alignment of two-base encoded DNA sequence

    PubMed Central

    Homer, Nils; Merriman, Barry; Nelson, Stanley F

    2009-01-01

    Background DNA sequence comparison is based on optimal local alignment of two sequences using a similarity score. However, some new DNA sequencing technologies do not directly measure the base sequence, but rather an encoded form, such as the two-base encoding considered here. In order to compare such data to a reference sequence, the data must be decoded into sequence. The decoding is deterministic, but the possibility of measurement errors requires searching among all possible error modes and resulting alignments to achieve an optimal balance of fewer errors versus greater sequence similarity. Results We present an extension of the standard dynamic programming method for local alignment, which simultaneously decodes the data and performs the alignment, maximizing a similarity score based on a weighted combination of errors and edits, and allowing an affine gap penalty. We also present simulations that demonstrate the performance characteristics of our two base encoded alignment method and contrast those with standard DNA sequence alignment under the same conditions. Conclusion The new local alignment algorithm for two-base encoded data has substantial power to properly detect and correct measurement errors while identifying underlying sequence variants, and facilitating genome re-sequencing efforts based on this form of sequence data. PMID:19508732

  11. Fast alignment-free sequence comparison using spaced-word frequencies.

    PubMed

    Leimeister, Chris-Andre; Boden, Marcus; Horwege, Sebastian; Lindner, Sebastian; Morgenstern, Burkhard

    2014-07-15

    Alignment-free methods for sequence comparison are increasingly used for genome analysis and phylogeny reconstruction; they circumvent various difficulties of traditional alignment-based approaches. In particular, alignment-free methods are much faster than pairwise or multiple alignments. They are, however, less accurate than methods based on sequence alignment. Most alignment-free approaches work by comparing the word composition of sequences. A well-known problem with these methods is that neighbouring word matches are far from independent. To reduce the statistical dependency between adjacent word matches, we propose to use 'spaced words', defined by patterns of 'match' and 'don't care' positions, for alignment-free sequence comparison. We describe a fast implementation of this approach using recursive hashing and bit operations, and we show that further improvements can be achieved by using multiple patterns instead of single patterns. To evaluate our approach, we use spaced-word frequencies as a basis for fast phylogeny reconstruction. Using real-world and simulated sequence data, we demonstrate that our multiple-pattern approach produces better phylogenies than approaches relying on contiguous words. Our program is freely available at http://spaced.gobics.de/. © The Author 2014. Published by Oxford University Press.

  12. "Performance Of A Wafer Stepper With Automatic Intra-Die Registration Correction."

    NASA Astrophysics Data System (ADS)

    van den Brink, M. A.; Wittekoek, S.; Linders, H. F. D.; van Hout, F. J.; George, R. A.

    1987-01-01

    An evaluation of a wafer stepper with the new improved Philips/ASM-L phase grating alignment system is reported. It is shown that an accurate alignment system needs an accurate X-Y-0 wafer stage and an accurate reticle Z stage to realize optimum overlay accuracy. This follows from a discussion of the overlay budget and an alignment procedure model. The accurate wafer stage permits high overlay accuracy using global alignment only, thus eliminating the throughput penalty of align-by-field schemes. The accurate reticle Z stage enables an intra-die magnification control with respect to the wafer scale. Various overlay data are reported, which have been measured with the automatic metrology program of the stepper. It is demonstrated that the new dual alignment system (with the external spatial filter) has improved the ability to align to weakly reflecting layers. The results are supported by a Fourier analysis of the alignment signal. Resolution data are given for the PAS 2500 projection lenses, which show that the high overlay accuracy of the system is properly matched with submicron linewidth control. The results of a recently introduced 20mm i-line lens with a numerical aperture of 0.4 (Zeiss 10-78-58) are included.

  13. Estimation of relative effectiveness of phylogenetic programs by machine learning.

    PubMed

    Krivozubov, Mikhail; Goebels, Florian; Spirin, Sergei

    2014-04-01

    Reconstruction of phylogeny of a protein family from a sequence alignment can produce results of different quality. Our goal is to predict the quality of phylogeny reconstruction basing on features that can be extracted from the input alignment. We used Fitch-Margoliash (FM) method of phylogeny reconstruction and random forest as a predictor. For training and testing the predictor, alignments of orthologous series (OS) were used, for which the result of phylogeny reconstruction can be evaluated by comparison with trees of corresponding organisms. Our results show that the quality of phylogeny reconstruction can be predicted with more than 80% precision. Also, we tried to predict which phylogeny reconstruction method, FM or UPGMA, is better for a particular alignment. With the used set of features, among alignments for which the obtained predictor predicts a better performance of UPGMA, 56% really give a better result with UPGMA. Taking into account that in our testing set only for 34% alignments UPGMA performs better, this result shows a principal possibility to predict the better phylogeny reconstruction method basing on features of a sequence alignment.

  14. Simulation of exposure and alignment for nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Deng, Yunfei; Neureuther, Andrew R.

    2002-07-01

    Rigorous electromagnetic simulation with TEMPEST is used to examine the exposure and alignment processes for nano-imprint lithography with attenuating thin-film molds. Parameters in the design of topographical features of the nano-imprint system and material choices of the components are analyzed. The small feature size limits light transmission through the feature. While little can be done with auxiliary structures to attract light into small holes, the use of an absorbing material with a low real part of the refractive index such as silver helps mitigates the problem. Results on complementary alignment marks shows that the small transmission through the metal layer and the vertical separation of two alignment marks create the leakage equivalent to 1 nm misalignment but satisfactory alignment can be obtained by measuring alignment signals over a +/- 30 nm range.

  15. A Method for the Alignment of Heterogeneous Macromolecules from Electron Microscopy

    PubMed Central

    Shatsky, Maxim; Hall, Richard J.; Brenner, Steven E.; Glaeser, Robert M.

    2009-01-01

    We propose a feature-based image alignment method for single-particle electron microscopy that is able to accommodate various similarity scoring functions while efficiently sampling the two-dimensional transformational space. We use this image alignment method to evaluate the performance of a scoring function that is based on the Mutual Information (MI) of two images rather than one that is based on the cross-correlation function. We show that alignment using MI for the scoring function has far less model-dependent bias than is found with cross-correlation based alignment. We also demonstrate that MI improves the alignment of some types of heterogeneous data, provided that the signal to noise ratio is relatively high. These results indicate, therefore, that use of MI as the scoring function is well suited for the alignment of class-averages computed from single particle images. Our method is tested on data from three model structures and one real dataset. PMID:19166941

  16. Simple chained guide trees give high-quality protein multiple sequence alignments

    PubMed Central

    Boyce, Kieran; Sievers, Fabian; Higgins, Desmond G.

    2014-01-01

    Guide trees are used to decide the order of sequence alignment in the progressive multiple sequence alignment heuristic. These guide trees are often the limiting factor in making large alignments, and considerable effort has been expended over the years in making these quickly or accurately. In this article we show that, at least for protein families with large numbers of sequences that can be benchmarked with known structures, simple chained guide trees give the most accurate alignments. These also happen to be the fastest and simplest guide trees to construct, computationally. Such guide trees have a striking effect on the accuracy of alignments produced by some of the most widely used alignment packages. There is a marked increase in accuracy and a marked decrease in computational time, once the number of sequences goes much above a few hundred. This is true, even if the order of sequences in the guide tree is random. PMID:25002495

  17. Phylogenic inference using alignment-free methods for applications in microbial community surveys using 16s rRNA gene

    PubMed Central

    2017-01-01

    The diversity of microbiota is best explored by understanding the phylogenetic structure of the microbial communities. Traditionally, sequence alignment has been used for phylogenetic inference. However, alignment-based approaches come with significant challenges and limitations when massive amounts of data are analyzed. In the recent decade, alignment-free approaches have enabled genome-scale phylogenetic inference. Here we evaluate three alignment-free methods: ACS, CVTree, and Kr for phylogenetic inference with 16s rRNA gene data. We use a taxonomic gold standard to compare the accuracy of alignment-free phylogenetic inference with that of common microbiome-wide phylogenetic inference pipelines based on PyNAST and MUSCLE alignments with FastTree and RAxML. We re-simulate fecal communities from Human Microbiome Project data to evaluate the performance of the methods on datasets with properties of real data. Our comparisons show that alignment-free methods are not inferior to alignment-based methods in giving accurate and robust phylogenic trees. Moreover, consensus ensembles of alignment-free phylogenies are superior to those built from alignment-based methods in their ability to highlight community differences in low power settings. In addition, the overall running times of alignment-based and alignment-free phylogenetic inference are comparable. Taken together our empirical results suggest that alignment-free methods provide a viable approach for microbiome-wide phylogenetic inference. PMID:29136663

  18. The Impact of Teacher Observations with Coordinated Professional Development on Student Performance: A 27-State Program Evaluation

    ERIC Educational Resources Information Center

    Shaha, Steven H.; Glassett, Kelly F.; Copas, Aimee

    2015-01-01

    The impact of teacher observations in alignment with professional development (PD) on teacher efficacy was quantified for 292 schools in 110 districts within 27 U.S. States. Teacher observations conducted by school leaders or designated internal coaches were coordinated with PD offerings aligned with intended teacher improvements. The PD involved…

  19. Uncommonly Engaging? A Review of the EngageNY English Language Arts Common Core Curriculum

    ERIC Educational Resources Information Center

    Haydel, Elizabeth; Carmichael, Sheila Byrd

    2015-01-01

    The need for standards-aligned curricula is the most cited Common Core challenge for states, districts, and schools. Yet five years into that implementation, teachers still report scrambling to find high-quality instructional materials. Despite publishers' claims, there is a dearth of programs that are truly aligned to the demands of the Common…

  20. Alignment and Calibration of an Airborne Infrared Spectrometer

    NASA Astrophysics Data System (ADS)

    Vira, A.

    2017-12-01

    The airborne infrared spectrometer (AIR-Spec) will measure the coronal plasma emission lines in the infrared at high spatial and spectral resolution. These results will enhance our understanding of the coronal dynamics and improve solar forecasting models. To measure the infrared coronal emission lines, the airborne system will fly on the NSF/NCAR High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) during the total solar eclipse in August 2017. The flight path was calculated to maximize the observation time. A detailed analysis of our flight path will be reported. The optical system consists of a fast steering mirror, telescope, grating spectrometer, and slit-jaw imager. Light from the sun is directed into the f/15 telescope by a fast steering mirror. The telescope focuses the light on the slitjaw and the remaining light enters the grating spectrometer through the slit. The poster will include a discussion of the alignment procedures for the telescope and spectrograph. All of the spectrometer optics are cooled to cryogenic temperatures, which complicates the alignment process. After the telescope and spectrometer are aligned independently, the telescope needs to be precisely aligned to the spectrometer. Several alignment methods were used to ensure that the telescope is focused at the slitjaw and normal to the spectrometer. In addition to the optical alignment, there are a few calibrations to complete: 1) flat field, 2) spectral, and 3) radiometric. The flat field gives us a measure of the pixel to pixel variations. The spectral calibration is used to determine the conversion factor between wavelength and pixel. The radiometric calibration is used to map the camera output to radiance. All these calibrations are necessary for processing our data from the solar eclipse. We will report on our methods and results for the optical alignment and calibration for AIR-Spec. AIR-Spec is supported by NSF and Smithsonian Institution through the Major Research Instrumentation program. This work is supported by the NSF-REU solar physics program at SAO, grant number AGS-1560313.

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