Fundamental limits of repeaterless quantum communications

PubMed Central

Pirandola, Stefano; Laurenza, Riccardo; Ottaviani, Carlo; Banchi, Leonardo

2017-01-01

Quantum communications promises reliable transmission of quantum information, efficient distribution of entanglement and generation of completely secure keys. For all these tasks, we need to determine the optimal point-to-point rates that are achievable by two remote parties at the ends of a quantum channel, without restrictions on their local operations and classical communication, which can be unlimited and two-way. These two-way assisted capacities represent the ultimate rates that are reachable without quantum repeaters. Here, by constructing an upper bound based on the relative entropy of entanglement and devising a dimension-independent technique dubbed ‘teleportation stretching', we establish these capacities for many fundamental channels, namely bosonic lossy channels, quantum-limited amplifiers, dephasing and erasure channels in arbitrary dimension. In particular, we exactly determine the fundamental rate-loss tradeoff affecting any protocol of quantum key distribution. Our findings set the limits of point-to-point quantum communications and provide precise and general benchmarks for quantum repeaters. PMID:28443624

Fundamental limits of repeaterless quantum communications.

PubMed

Pirandola, Stefano; Laurenza, Riccardo; Ottaviani, Carlo; Banchi, Leonardo

2017-04-26

Quantum communications promises reliable transmission of quantum information, efficient distribution of entanglement and generation of completely secure keys. For all these tasks, we need to determine the optimal point-to-point rates that are achievable by two remote parties at the ends of a quantum channel, without restrictions on their local operations and classical communication, which can be unlimited and two-way. These two-way assisted capacities represent the ultimate rates that are reachable without quantum repeaters. Here, by constructing an upper bound based on the relative entropy of entanglement and devising a dimension-independent technique dubbed 'teleportation stretching', we establish these capacities for many fundamental channels, namely bosonic lossy channels, quantum-limited amplifiers, dephasing and erasure channels in arbitrary dimension. In particular, we exactly determine the fundamental rate-loss tradeoff affecting any protocol of quantum key distribution. Our findings set the limits of point-to-point quantum communications and provide precise and general benchmarks for quantum repeaters.

Investigation of a Quadruplex-Forming Repeat Sequence Highly Enriched in Xanthomonas and Nostoc sp.

PubMed

Rehm, Charlotte; Wurmthaler, Lena A; Li, Yuanhao; Frickey, Tancred; Hartig, Jörg S

2015-01-01

In prokaryotes simple sequence repeats (SSRs) with unit sizes of 1-5 nucleotides (nt) are causative for phase and antigenic variation. Although an increased abundance of heptameric repeats was noticed in bacteria, reports about SSRs of 6-9 nt are rare. In particular G-rich repeat sequences with the propensity to fold into G-quadruplex (G4) structures have received little attention. In silico analysis of prokaryotic genomes show putative G4 forming sequences to be abundant. This report focuses on a surprisingly enriched G-rich repeat of the type GGGNATC in Xanthomonas and cyanobacteria such as Nostoc. We studied in detail the genomes of Xanthomonas campestris pv. campestris ATCC 33913 (Xcc), Xanthomonas axonopodis pv. citri str. 306 (Xac), and Nostoc sp. strain PCC7120 (Ana). In all three organisms repeats are spread all over the genome with an over-representation in non-coding regions. Extensive variation of the number of repetitive units was observed with repeat numbers ranging from two up to 26 units. However a clear preference for four units was detected. The strong bias for four units coincides with the requirement of four consecutive G-tracts for G4 formation. Evidence for G4 formation of the consensus repeat sequences was found in biophysical studies utilizing CD spectroscopy. The G-rich repeats are preferably located between aligned open reading frames (ORFs) and are under-represented in coding regions or between divergent ORFs. The G-rich repeats are preferentially located within a distance of 50 bp upstream of an ORF on the anti-sense strand or within 50 bp from the stop codon on the sense strand. Analysis of whole transcriptome sequence data showed that the majority of repeat sequences are transcribed. The genetic loci in the vicinity of repeat regions show increased genomic stability. In conclusion, we introduce and characterize a special class of highly abundant and wide-spread quadruplex-forming repeat sequences in bacteria.

Investigation of a Quadruplex-Forming Repeat Sequence Highly Enriched in Xanthomonas and Nostoc sp.

PubMed Central

Rehm, Charlotte; Wurmthaler, Lena A.; Li, Yuanhao; Frickey, Tancred; Hartig, Jörg S.

2015-01-01

In prokaryotes simple sequence repeats (SSRs) with unit sizes of 1–5 nucleotides (nt) are causative for phase and antigenic variation. Although an increased abundance of heptameric repeats was noticed in bacteria, reports about SSRs of 6–9 nt are rare. In particular G-rich repeat sequences with the propensity to fold into G-quadruplex (G4) structures have received little attention. In silico analysis of prokaryotic genomes show putative G4 forming sequences to be abundant. This report focuses on a surprisingly enriched G-rich repeat of the type GGGNATC in Xanthomonas and cyanobacteria such as Nostoc. We studied in detail the genomes of Xanthomonas campestris pv. campestris ATCC 33913 (Xcc), Xanthomonas axonopodis pv. citri str. 306 (Xac), and Nostoc sp. strain PCC7120 (Ana). In all three organisms repeats are spread all over the genome with an over-representation in non-coding regions. Extensive variation of the number of repetitive units was observed with repeat numbers ranging from two up to 26 units. However a clear preference for four units was detected. The strong bias for four units coincides with the requirement of four consecutive G-tracts for G4 formation. Evidence for G4 formation of the consensus repeat sequences was found in biophysical studies utilizing CD spectroscopy. The G-rich repeats are preferably located between aligned open reading frames (ORFs) and are under-represented in coding regions or between divergent ORFs. The G-rich repeats are preferentially located within a distance of 50 bp upstream of an ORF on the anti-sense strand or within 50 bp from the stop codon on the sense strand. Analysis of whole transcriptome sequence data showed that the majority of repeat sequences are transcribed. The genetic loci in the vicinity of repeat regions show increased genomic stability. In conclusion, we introduce and characterize a special class of highly abundant and wide-spread quadruplex-forming repeat sequences in bacteria. PMID:26695179

Micromechanics Fatigue Damage Analysis Modeling for Fabric Reinforced Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Min, J. B.; Xue, D.; Shi, Y.

2013-01-01

A micromechanics analysis modeling method was developed to analyze the damage progression and fatigue failure of fabric reinforced composite structures, especially for the brittle ceramic matrix material composites. A repeating unit cell concept of fabric reinforced composites was used to represent the global composite structure. The thermal and mechanical properties of the repeating unit cell were considered as the same as those of the global composite structure. The three-phase micromechanics, the shear-lag, and the continuum fracture mechanics models were integrated with a statistical model in the repeating unit cell to predict the progressive damages and fatigue life of the composite structures. The global structure failure was defined as the loss of loading capability of the repeating unit cell, which depends on the stiffness reduction due to material slice failures and nonlinear material properties in the repeating unit cell. The present methodology is demonstrated with the analysis results evaluated through the experimental test performed with carbon fiber reinforced silicon carbide matrix plain weave composite specimens.

Biophysical characterization of soluble Pseudomonas syringae ice nucleation protein InaZ fragments.

PubMed

Han, Yu Jin; Song, HyoJin; Lee, Chang Woo; Ly, Nguyễn Hoàng; Joo, Sang-Woo; Lee, Jun Hyuck; Kim, Soon-Jong; Park, SangYoun

2017-01-01

Ice nucleation protein (INP) with its functional domain consisting of multiple 48-residue repeat units effectively induces super-cooled water into ice. Circular dichroism and infrared deconvolution analyses on a soluble 240-residue fragment of Pseudomonas syringae InaZ (InaZ240) containing five 48-residue repeat units indicated that it is mostly composed of β-sheet and random coil. Analytical ultracentrifugation suggested that InaZ240 behaves as a monomer of an elongated ellipsoid. However, InaZ240 showed only minimum ice binding compared to anti-freeze proteins. Other P. syringae InaZ proteins with more 48-residue repeat units were made, in which the largest soluble fragment obtainable was an InaZ with twelve 48-residue repeat units. Size-exclusion chromatography analyses further suggested that the overall shape of the expressed InaZ fragments is pH-dependent, which becomes compact as the numbers of 48-residue repeat unit increase. Copyright © 2016 Elsevier B.V. All rights reserved.

Evolution of Protein Domain Repeats in Metazoa

PubMed Central

Schüler, Andreas; Bornberg-Bauer, Erich

2016-01-01

Repeats are ubiquitous elements of proteins and they play important roles for cellular function and during evolution. Repeats are, however, also notoriously difficult to capture computationally and large scale studies so far had difficulties in linking genetic causes, structural properties and evolutionary trajectories of protein repeats. Here we apply recently developed methods for repeat detection and analysis to a large dataset comprising over hundred metazoan genomes. We find that repeats in larger protein families experience generally very few insertions or deletions (indels) of repeat units but there is also a significant fraction of noteworthy volatile outliers with very high indel rates. Analysis of structural data indicates that repeats with an open structure and independently folding units are more volatile and more likely to be intrinsically disordered. Such disordered repeats are also significantly enriched in sites with a high functional potential such as linear motifs. Furthermore, the most volatile repeats have a high sequence similarity between their units. Since many volatile repeats also show signs of recombination, we conclude they are often shaped by concerted evolution. Intriguingly, many of these conserved yet volatile repeats are involved in host-pathogen interactions where they might foster fast but subtle adaptation in biological arms races. Key Words: protein evolution, domain rearrangements, protein repeats, concerted evolution. PMID:27671125

Repeater F-waves are signs of motor unit pathology in polio survivors.

PubMed

Hachisuka, Akiko; Komori, Tetsuo; Abe, Tatsuya; Hachisuka, Kenji

2015-05-01

The purpose of this study was to determine whether F-waves reveal electrophysiological features of anterior horn cells in polio survivors. Forty-three polio survivors and 20 healthy controls underwent motor nerve conduction studies of the median and tibial nerves bilaterally, including sampling of F-waves elicited by 100 stimuli and the determination of motor unit number estimation (MUNE). A significant increase in abnormally stereotyped ("repeater") F-waves and a reduction of F-wave persistence were observed in both nerves in the polio group as compared with the control group. Repeater F-waves had a negative correlation with MUNE. These trends in F-wave persistence and repeater F-waves after motor unit loss are characteristic findings in polio survivors. Repeater F-waves are a sign of motor unit pathology. © 2014 The Authors. Muscle & Nerve Published by Wiley Periodicals, Inc.

Evaluating fundamentals of care: The development of a unit-level quality measurement and improvement programme.

PubMed

Parr, Jenny M; Bell, Jeanette; Koziol-McLain, Jane

2018-06-01

The project aimed to develop a unit-level quality measurement and improvement programme using evidence-based fundamentals of care. Feedback from patients, families, whānau, staff and audit data in 2014 indicated variability in the delivery of fundamental aspects of care such as monitoring, nutrition, pain management and environmental cleanliness at a New Zealand District Health Board. A general inductive approach was used to explore the fundamentals of care and design a measurement and improvement programme, the Patient and Whānau Centred Care Standards (PWCCS), focused on fundamental care. Five phases were used to explore the evidence, and design and test a measurement and improvement framework. Nine identified fundamental elements of care were used to define expected standards of care and develop and test a measurement and improvement framework. Four six-monthly peer reviews have been undertaken since June 2015. Charge Nurse Managers used results to identify quality improvements. Significant improvement was demonstrated overall, in six of the 27 units, in seven of the nine standards and three of the four measures. In all, 89% (n = 24) of units improved their overall result. The PWCCS measurement and improvement framework make visible nursing fundamentals of care in line with continuous quality improvement to increase quality of care. Delivering fundamentals of care is described by nurses as getting ?back to basics'. Patient and family feedback supports the centrality of fundamentals of care to their hospital experience. Implementing a unit-level fundamentals of care quality measurement and improvement programme clarifies expected standards of care, highlights the contribution of fundamentals of care to quality and provides a mechanism for ongoing improvements. © 2018 John Wiley & Sons Ltd.

DNA replication through a chromatin environment.

PubMed

Bellush, James M; Whitehouse, Iestyn

2017-10-05

Compaction of the genome into the nuclear space is achieved by wrapping DNA around octameric assemblies of histone proteins to form nucleosomes, the fundamental repeating unit of chromatin. Aside from providing a means by which to fit larger genomes into the cell, chromatinization of DNA is a crucial means by which the cell regulates access to the genome. While the complex role that chromatin plays in gene transcription has been appreciated for a long time, it is now also apparent that crucial aspects of DNA replication are linked to the biology of chromatin. This review will focus on recent advances in our understanding of how the chromatin environment influences key aspects of DNA replication.This article is part of the themed issue 'Chromatin modifiers and remodellers in DNA repair and signalling'. © 2017 The Author(s).

Concerning Units.

ERIC Educational Resources Information Center

Wadlinger, Robert L.

1983-01-01

SI units come in two distinct types: fundamental (kilogram, meter) and descriptive (atom, molecule). Proper/improper uses of atom/molecule from historical cases are presented followed by a re-introduction of a light "wave (cycle)" unit and the clearly defined photon model which is deduced. Also examines omission of the fundamental unit "radon."…

Electromyographic analysis of repeated bouts of eccentric exercise.

PubMed

McHugh, M P; Connolly, D A; Eston, R G; Gartman, E J; Gleim, G W

2001-03-01

The repeated bout effect refers to the protective effect provided by a single bout of eccentric exercise against muscle damage from a similar subsequent bout. The aim of this study was to determine if the repeated bout was associated with an increase in motor unit activation relative to force production, an increased recruitment of slow-twitch motor units or increased motor unit synchronization. Surface electromyographic (EMG) signals were recorded from the hamstring muscles during two bouts of submaximal isokinetic (2.6 rad x s(-1)) eccentric (11 men, 9 women) or concentric (6 men, 4 women) contractions separated by 2 weeks. The EMG per unit torque and median frequency were analysed. The initial bout of eccentric exercise resulted in strength loss, pain and muscle tenderness, while the repeated eccentric bout resulted in a slight increase in strength, no pain and no muscle tenderness (bout x time effects, P < 0.05). Strength, pain and tenderness were unaffected by either bout of concentric exercise. The EMG per unit torque and median frequency were not different between the initial and repeated bouts of eccentric exercise. The EMG per unit torque and median frequency increased during both bouts of eccentric exercise (P < 0.01) but did not change during either concentric bout. In conclusion, there was no evidence that the repeated bout effect was due to a neural adaptation.

Repeated reunions and splits feature the highly dynamic evolution of 5S and 35S ribosomal RNA genes (rDNA) in the Asteraceae family.

PubMed

Garcia, Sònia; Panero, José L; Siroky, Jiri; Kovarik, Ales

2010-08-16

In flowering plants and animals the most common ribosomal RNA genes (rDNA) organisation is that in which 35S (encoding 18S-5.8S-26S rRNA) and 5S genes are physically separated occupying different chromosomal loci. However, recent observations established that both genes have been unified to a single 35S-5S unit in the genus Artemisia (Asteraceae), a genomic arrangement typical of primitive eukaryotes such as yeast, among others. Here we aim to reveal the origin, distribution and mechanisms leading to the linked organisation of rDNA in the Asteraceae by analysing unit structure (PCR, Southern blot, sequencing), gene copy number (quantitative PCR) and chromosomal position (FISH) of 5S and 35S rRNA genes in approximately 200 species representing the family diversity and other closely related groups. Dominant linked rDNA genotype was found within three large groups in subfamily Asteroideae: tribe Anthemideae (93% of the studied cases), tribe Gnaphalieae (100%) and in the "Heliantheae alliance" (23%). The remaining five tribes of the Asteroideae displayed canonical non linked arrangement of rDNA, as did the other groups in the Asteraceae. Nevertheless, low copy linked genes were identified among several species that amplified unlinked units. The conserved position of functional 5S insertions downstream from the 26S gene suggests a unique, perhaps retrotransposon-mediated integration event at the base of subfamily Asteroideae. Further evolution likely involved divergence of 26S-5S intergenic spacers, amplification and homogenisation of units across the chromosomes and concomitant elimination of unlinked arrays. However, the opposite trend, from linked towards unlinked arrangement was also surmised in few species indicating possible reversibility of these processes. Our results indicate that nearly 25% of Asteraceae species may have evolved unusual linked arrangement of rRNA genes. Thus, in plants, fundamental changes in intrinsic structure of rDNA units, their copy number and chromosomal organisation may occur within relatively short evolutionary time. We hypothesize that the 5S gene integration within the 35S unit might have repeatedly occurred during plant evolution, and probably once in Asteraceae.

Repeated reunions and splits feature the highly dynamic evolution of 5S and 35S ribosomal RNA genes (rDNA) in the Asteraceae family

PubMed Central

2010-01-01

Background In flowering plants and animals the most common ribosomal RNA genes (rDNA) organisation is that in which 35S (encoding 18S-5.8S-26S rRNA) and 5S genes are physically separated occupying different chromosomal loci. However, recent observations established that both genes have been unified to a single 35S-5S unit in the genus Artemisia (Asteraceae), a genomic arrangement typical of primitive eukaryotes such as yeast, among others. Here we aim to reveal the origin, distribution and mechanisms leading to the linked organisation of rDNA in the Asteraceae by analysing unit structure (PCR, Southern blot, sequencing), gene copy number (quantitative PCR) and chromosomal position (FISH) of 5S and 35S rRNA genes in ~200 species representing the family diversity and other closely related groups. Results Dominant linked rDNA genotype was found within three large groups in subfamily Asteroideae: tribe Anthemideae (93% of the studied cases), tribe Gnaphalieae (100%) and in the "Heliantheae alliance" (23%). The remaining five tribes of the Asteroideae displayed canonical non linked arrangement of rDNA, as did the other groups in the Asteraceae. Nevertheless, low copy linked genes were identified among several species that amplified unlinked units. The conserved position of functional 5S insertions downstream from the 26S gene suggests a unique, perhaps retrotransposon-mediated integration event at the base of subfamily Asteroideae. Further evolution likely involved divergence of 26S-5S intergenic spacers, amplification and homogenisation of units across the chromosomes and concomitant elimination of unlinked arrays. However, the opposite trend, from linked towards unlinked arrangement was also surmised in few species indicating possible reversibility of these processes. Conclusions Our results indicate that nearly 25% of Asteraceae species may have evolved unusual linked arrangement of rRNA genes. Thus, in plants, fundamental changes in intrinsic structure of rDNA units, their copy number and chromosomal organisation may occur within relatively short evolutionary time. We hypothesize that the 5S gene integration within the 35S unit might have repeatedly occurred during plant evolution, and probably once in Asteraceae. PMID:20712858

Contact and Length Dependent Effects in Single-Molecule Electronics

NASA Astrophysics Data System (ADS)

Hines, Thomas

Understanding charge transport in single molecules covalently bonded to electrodes is a fundamental goal in the field of molecular electronics. In the past decade, it has become possible to measure charge transport on the single-molecule level using the STM break junction method. Measurements on the single-molecule level shed light on charge transport phenomena which would otherwise be obfuscated by ensemble measurements of groups of molecules. This thesis will discuss three projects carried out using STM break junction. In the first project, the transition between two different charge transport mechanisms is reported in a set of molecular wires. The shortest wires show highly length dependent and temperature invariant conductance behavior, whereas the longer wires show weakly length dependent and temperature dependent behavior. This trend is consistent with a model whereby conduction occurs by coherent tunneling in the shortest wires and by incoherent hopping in the longer wires. Measurements are supported with calculations and the evolution of the molecular junction during the pulling process is investigated. The second project reports controlling the formation of single-molecule junctions by means of electrochemically reducing two axial-diazonium terminal groups on a molecule, thereby producing direct Au-C covalent bonds in-situ between the molecule and gold electrodes. Step length analysis shows that the molecular junction is significantly more stable, and can be pulled over a longer distance than a comparable junction created with amine anchoring bonds. The stability of the junction is explained by the calculated lower binding energy associated with the direct Au-C bond compared with the Au-N bond. Finally, the third project investigates the role that molecular conformation plays in the conductance of oligothiophene single-molecule junctions. Ethyl substituted oligothiophenes were measured and found to exhibit temperature dependent conductance and transition voltage for molecules with between two and six repeat units. While the molecule with only one repeat unit shows temperature invariant behavior. Density functional theory calculations show that at higher temperatures the oligomers with multiple repeat units assume a more planar conformation, which increases the conjugation length and decreases the effective energy barrier of the junction.

Effects of iterative learning based signal control strategies on macroscopic fundamental diagrams of urban road networks

NASA Astrophysics Data System (ADS)

Yan, Fei; Tian, Fuli; Shi, Zhongke

2016-10-01

Urban traffic flows are inherently repeated on a daily or weekly basis. This repeatability can help improve the traffic conditions if it is used properly by the control system. In this paper, we propose a novel iterative learning control (ILC) strategy for traffic signals of urban road networks using the repeatability feature of traffic flow. To improve the control robustness, the ILC strategy is further integrated with an error feedback control law in a complementary manner. Theoretical analysis indicates that the ILC-based traffic signal control methods can guarantee the asymptotic learning convergence, despite the presence of modeling uncertainties and exogenous disturbances. Finally, the impacts of the ILC-based signal control strategies on the network macroscopic fundamental diagram (MFD) are examined. The results show that the proposed ILC-based control strategies can homogenously distribute the network accumulation by controlling the vehicle numbers in each link to the desired levels under different traffic demands, which can result in the network with high capacity and mobility.

Concerted evolution of the tandem array encoding primate U2 snRNA occurs in situ, without changing the cytological context of the RNU2 locus.

PubMed Central

Pavelitz, T; Rusché, L; Matera, A G; Scharf, J M; Weiner, A M

1995-01-01

In primates, the tandemly repeated genes encoding U2 small nuclear RNA evolve concertedly, i.e. the sequence of the U2 repeat unit is essentially homogeneous within each species but differs somewhat between species. Using chromosome painting and the NGFR gene as an outside marker, we show that the U2 tandem array (RNU2) has remained at the same chromosomal locus (equivalent to human 17q21) through multiple speciation events over > 35 million years leading to the Old World monkey and hominoid lineages. The data suggest that the U2 tandem repeat, once established in the primate lineage, contained sequence elements favoring perpetuation and concerted evolution of the array in situ, despite a pericentric inversion in chimpanzee, a reciprocal translocation in gorilla and a paracentric inversion in orang utan. Comparison of the 11 kb U2 repeat unit found in baboon and other Old World monkeys with the 6 kb U2 repeat unit in humans and other hominids revealed that an ancestral U2 repeat unit was expanded by insertion of a 5 kb retrovirus bearing 1 kb long terminal repeats (LTRs). Subsequent excision of the provirus by homologous recombination between the LTRs generated a 6 kb U2 repeat unit containing a solo LTR. Remarkably, both junctions between the human U2 tandem array and flanking chromosomal DNA at 17q21 fall within the solo LTR sequence, suggesting a role for the LTR in the origin or maintenance of the primate U2 array. Images PMID:7828589

Thermally crosslinked polymeric compositions and methods of making the same

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

Koros, William John; Kratochvil, Adam Michal

2014-03-04

The various embodiments of the present disclosure relate generally to thermally crosslinked polymeric compositions and methods of making thermally crosslinked polymeric compositions. An embodiment of the present invention comprises a composition comprising: a first polymer comprising a first repeat unit, the first repeat unit comprising a carboxyl group, wherein the first polymer crosslinks to a second polymer formed from a second repeat unit, and wherein the first polymer crosslinks to the second polymer without formation of an ester group.

Recombination-dependent replication and gene conversion homogenize repeat sequences and diversify plastid genome structure.

PubMed

Ruhlman, Tracey A; Zhang, Jin; Blazier, John C; Sabir, Jamal S M; Jansen, Robert K

2017-04-01

There is a misinterpretation in the literature regarding the variable orientation of the small single copy region of plastid genomes (plastomes). The common phenomenon of small and large single copy inversion, hypothesized to occur through intramolecular recombination between inverted repeats (IR) in a circular, single unit-genome, in fact, more likely occurs through recombination-dependent replication (RDR) of linear plastome templates. If RDR can be primed through both intra- and intermolecular recombination, then this mechanism could not only create inversion isomers of so-called single copy regions, but also an array of alternative sequence arrangements. We used Illumina paired-end and PacBio single-molecule real-time (SMRT) sequences to characterize repeat structure in the plastome of Monsonia emarginata (Geraniaceae). We used OrgConv and inspected nucleotide alignments to infer ancestral nucleotides and identify gene conversion among repeats and mapped long (>1 kb) SMRT reads against the unit-genome assembly to identify alternative sequence arrangements. Although M. emarginata lacks the canonical IR, we found that large repeats (>1 kilobase; kb) represent ∼22% of the plastome nucleotide content. Among the largest repeats (>2 kb), we identified GC-biased gene conversion and mapping filtered, long SMRT reads to the M. emarginata unit-genome assembly revealed alternative, substoichiometric sequence arrangements. We offer a model based on RDR and gene conversion between long repeated sequences in the M. emarginata plastome and provide support that both intra-and intermolecular recombination between large repeats, particularly in repeat-rich plastomes, varies unit-genome structure while homogenizing the nucleotide sequence of repeats. © 2017 Botanical Society of America.

Fundamental Movement Skills and Children with Attention-Deficit Hyperactivity Disorder: Peer Comparisons and Stimulant Effects

ERIC Educational Resources Information Center

Harvey, William J.; Reid, Greg; Grizenko, Natalie; Mbekou, Valentin; Ter-Stepanian, Marina; Joober, Ridha

2007-01-01

The purpose of this study was to compare the fundamental movement skills of 22 children with attention-deficit hyperactivity disorder (ADHD), from 6 to 12 years of age, to gender- and age-matched peers without ADHD and assess the effects of stimulant medication on the movement skill performance of the children with ADHD. Repeated measures analyses…

Efficient production of artificially designed gelatins with a Bacillus brevis system.

PubMed

Kajino, T; Takahashi, H; Hirai, M; Yamada, Y

2000-01-01

Artificially designed gelatins comprising tandemly repeated 30-amino-acid peptide units derived from human alphaI collagen were successfully produced with a Bacillus brevis system. The DNA encoding the peptide unit was synthesized by taking into consideration the codon usage of the host cells, but no clones having a tandemly repeated gene were obtained through the above-mentioned strategy. Minirepeat genes could be selected in vivo from a mixture of every possible sequence encoding an artificial gelatin by randomly ligating the mixed sequence unit and transforming it into Escherichia coli. Larger repeat genes constructed by connecting minirepeat genes obtained by in vivo selection were also stable in the expression host cells. Gelatins derived from the eight-unit and six-unit repeat genes were extracellularly produced at the level of 0.5 g/liter and easily purified by ammonium sulfate fractionation and anion-exchange chromatography. The purified artificial gelatins had the predicted N-terminal sequences and amino acid compositions and a solgel property similar to that of the native gelatin. These results suggest that the selection of a repeat unit sequence stable in an expression host is a shortcut for the efficient production of repetitive proteins and that it can conveniently be achieved by the in vivo selection method. This study revealed the possible industrial application of artificially designed repetitive proteins.

Enviroplan—a summary methodology for comprehensive environmental planning and design

Treesearch

Robert Allen Jr.; George Nez; Fred Nicholson; Larry Sutphin

1979-01-01

This paper will discuss a comprehensive environmental assessment methodology that includes a numerical method for visual management and analysis. This methodology employs resource and human activity units as a means to produce a visual form unit which is the fundamental unit of the perceptual environment. The resource unit is based on the ecosystem as the fundamental...

Multiple independent insertions of 5S rRNA genes in the spliced-leader gene family of trypanosome species.

PubMed

Beauparlant, Marc A; Drouin, Guy

2014-02-01

Analyses of the 5S rRNA genes found in the spliced-leader (SL) gene repeat units of numerous trypanosome species suggest that such linkages were not inherited from a common ancestor, but were the result of independent 5S rRNA gene insertions. In trypanosomes, 5S rRNA genes are found either in the tandemly repeated units coding for SL genes or in independent tandemly repeated units. Given that trypanosome species where 5S rRNA genes are within the tandemly repeated units coding for SL genes are phylogenetically related, one might hypothesize that this arrangement is the result of an ancestral insertion of 5S rRNA genes into the tandemly repeated SL gene family of trypanosomes. Here, we use the types of 5S rRNA genes found associated with SL genes, the flanking regions of the inserted 5S rRNA genes and the position of these insertions to show that most of the 5S rRNA genes found within SL gene repeat units of trypanosome species were not acquired from a common ancestor but are the results of independent insertions. These multiple 5S rRNA genes insertion events in trypanosomes are likely the result of frequent founder events in different hosts and/or geographical locations in species having short generation times.

Concerted evolution of the tandemly repeated genes encoding primate U2 small nuclear RNA (the RNU2 locus) does not prevent rapid diversification of the (CT){sub n} {center_dot} (GA){sub n} microsatellite embedded within the U2 repeat unit

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

Liao, D.; Weiner, A.M.

1995-12-10

The RNU2 locus encoding human U2 small nuclear RNA (snRNA) is organized as a nearly perfect tandem array containing 5 to 22 copies of a 5.8-kb repeat unit. Just downstream of the U2 snRNA gene in each 5.8-kb repeat unit lies a large (CT){sub n}{center_dot}(GA){sub n} dinucleotide repeat (n {approx} 70). This form of genomic organization, in which one repeat is embedded within another, provides an unusual opportunity to study the balance of forces maintaining the homogeneity of both kinds of repeats. Using a combination of field inversion gel electrophoresis and polymerase chain reaction, we have been able to studymore » the CT microsatellites within individual U2 tandem arrays. We find that the CT microsatellites within an RNU2 allele exhibit significant length polymorphism, despite the remarkable homogeneity of the surrounding U2 repeat units. Length polymorphism is due primarily to loss or gain of CT dinucleotide repeats, but other types of deletions, insertions, and substitutions are also frequent. Polymorphism is greatly reduced in regions where pure (CT){sub n} tracts are interrupted by occasional G residues, suggesting that irregularities stabilize both the length and the sequence of the dinucleotide repeat. We further show that the RNU2 loci of other catarrhine primates (gorilla, chimpanzee, ogangutan, and baboon) contain orthologous CT microsatellites; these also exhibit length polymorphism, but are highly divergent from each other. Thus, although the CT microsatellite is evolving far more rapidly than the rest of the U2 repeat unit, it has persisted through multiple speciation events spanning >35 Myr. The persistence of the CT microsatellite, despite polymorphism and rapid evolution, suggests that it might play a functional role in concerted evolution of the RNU2 loci, perhaps as an initiation site for recombination and/or gene conversion. 70 refs., 5 figs.« less

Fitness determinants of repeated-sprint ability in highly trained youth football players.

PubMed

Spencer, Matt; Pyne, David; Santisteban, Juanma; Mujika, Iñigo

2011-12-01

Variations in rates of growth and development in young football players can influence relationships among various fitness qualities. To investigate the relationships between repeated-sprint ability and other fundamental fitness qualities of acceleration, agility, explosive leg power, and aerobic conditioning through the age groups of U11 to U18 in highly trained junior football players. Male players (n = 119) across the age groups completed a fitness assessment battery over two testing sessions. The first session consisted of countermovement jumps without and with arm swing, 15-m sprint run, 15-m agility run, and the 20-m Shuttle Run (U11 to U15) or the Yo-Yo Intermittent Recovery Test, Level 1 (U16 to U18). The players were tested for repeated-sprint ability in the second testing session using a protocol of 6 × 30-m sprints on 30 s with an active recovery. The correlations of repeated-sprint ability with the assorted fitness tests varied considerably between the age groups, especially for agility (r = .02 to .92) and explosive leg power (r = .04 to .84). Correlations of repeated sprint ability with acceleration (r = .48 to .93) and aerobic conditioning (r = .28 to .68) were less variable with age. Repeated-sprint ability associates differently with other fundamental fitness tests throughout the teenage years in highly trained football players, although stabilization of these relationships occurs by the age of 18 y. Coaches in junior football should prescribe physical training accounting for variations in short-term disruptions or impairment of physical performance during this developmental period.

Curriculum enrichment with self-testing activities in development of fundamental movement skills of first-grade children in Greece.

PubMed

Karabourniotis, Dimitrios; Evaggelinou, Christina; Tzetzis, George; Kourtessis, Thomas

2002-06-01

The purpose of this study was to investigate the effect of self-testing activities on the development of fundamental movement skills in first-grade children in Greece. Two groups of children were tested. The Control group (n = 23 children) received the regular 12-wk. physical education school program and the Experimental group (n = 22 children) received a 12-wk. skill-oriented program with an increasing allotment of self-testing activities. The Test of Gross Motor Development was used to assess fundamental movement skills, while the content areas of physical education courses were estimated with an assessment protocol, based on the interval recording system called the Academic Learning Time-Physical Education. A 2 x 2 repeated measures analysis of variance with group as the between factor and testing time (pretest vs posttest) as the repeated-measures factor was performed to assess differences between the two groups. A significant interaction of group with testing time was found for the Test of Gross Motor Development total score, with the Experimental group scoring higher then the Control group. A significant main effect was also found for test but not for group. This study provides evidence supporting the notion that a balanced allotment of the self-testing and game activities beyond the usual curriculum increases the fundamental motor-skill development of children. Also, it stresses the necessity for content and performance standards for the fundamental motor skills in educational programs. Finally, it seems that the Test of Gross Motor Development is a useful tool for the assessment of children's fundamental movement skills.

Structure, organization, and sequence of alpha satellite DNA from human chromosome 17: evidence for evolution by unequal crossing-over and an ancestral pentamer repeat shared with the human X chromosome.

PubMed

Waye, J S; Willard, H F

1986-09-01

The centromeric regions of all human chromosomes are characterized by distinct subsets of a diverse tandemly repeated DNA family, alpha satellite. On human chromosome 17, the predominant form of alpha satellite is a 2.7-kilobase-pair higher-order repeat unit consisting of 16 alphoid monomers. We present the complete nucleotide sequence of the 16-monomer repeat, which is present in 500 to 1,000 copies per chromosome 17, as well as that of a less abundant 15-monomer repeat, also from chromosome 17. These repeat units were approximately 98% identical in sequence, differing by the exclusion of precisely 1 monomer from the 15-monomer repeat. Homologous unequal crossing-over is suggested as a probable mechanism by which the different repeat lengths on chromosome 17 were generated, and the putative site of such a recombination event is identified. The monomer organization of the chromosome 17 higher-order repeat unit is based, in part, on tandemly repeated pentamers. A similar pentameric suborganization has been previously demonstrated for alpha satellite of the human X chromosome. Despite the organizational similarities, substantial sequence divergence distinguishes these subsets. Hybridization experiments indicate that the chromosome 17 and X subsets are more similar to each other than to the subsets found on several other human chromosomes. We suggest that the chromosome 17 and X alpha satellite subsets may be related components of a larger alphoid subfamily which have evolved from a common ancestral repeat into the contemporary chromosome-specific subsets.

Evolution and selection of Rhg1, a copy-number variant nematode-resistance locus

PubMed Central

Lee, Tong Geon; Kumar, Indrajit; Diers, Brian W; Hudson, Matthew E

2015-01-01

The soybean cyst nematode (SCN) resistance locus Rhg1 is a tandem repeat of a 31.2 kb unit of the soybean genome. Each 31.2-kb unit contains four genes. One allele of Rhg1, Rhg1-b, is responsible for protecting most US soybean production from SCN. Whole-genome sequencing was performed, and PCR assays were developed to investigate allelic variation in sequence and copy number of the Rhg1 locus across a population of soybean germplasm accessions. Four distinct sequences of the 31.2-kb repeat unit were identified, and some Rhg1 alleles carry up to three different types of repeat unit. The total number of copies of the repeat varies from 1 to 10 per haploid genome. Both copy number and sequence of the repeat correlate with the resistance phenotype, and the Rhg1 locus shows strong signatures of selection. Significant linkage disequilibrium in the genome outside the boundaries of the repeat allowed the Rhg1 genotype to be inferred using high-density single nucleotide polymorphism genotyping of 15 996 accessions. Over 860 germplasm accessions were found likely to possess Rhg1 alleles. The regions surrounding the repeat show indications of non-neutral evolution and high genetic variability in populations from different geographic locations, but without evidence of fixation of the resistant genotype. A compelling explanation of these results is that balancing selection is in operation at Rhg1. PMID:25735447

Length and sequence heterogeneity in 5S rDNA of Populus deltoides.

PubMed

Negi, Madan S; Rajagopal, Jyothi; Chauhan, Neeti; Cronn, Richard; Lakshmikumaran, Malathi

2002-12-01

The 5S rRNA genes and their associated non-transcribed spacer (NTS) regions are present as repeat units arranged in tandem arrays in plant genomes. Length heterogeneity in 5S rDNA repeats was previously identified in Populus deltoides and was also observed in the present study. Primers were designed to amplify the 5S rDNA NTS variants from the P. deltoides genome. The PCR-amplified products from the two accessions of P. deltoides (G3 and G48) suggested the presence of length heterogeneity of 5S rDNA units within and among accessions, and the size of the spacers ranged from 385 to 434 bp. Sequence analysis of the non-transcribed spacer (NTS) revealed two distinct classes of 5S rDNA within both accessions: class 1, which contained GAA trinucleotide microsatellite repeats, and class 2, which lacked the repeats. The class 1 spacer shows length variation owing to the microsatellite, with two clones exhibiting 10 GAA repeat units and one clone exhibiting 16 such repeat units. However, distance analysis shows that class 1 spacer sequences are highly similar inter se, yielding nucleotide diversity (pi) estimates that are less than 0.15% of those obtained for class 2 spacers (pi = 0.0183 vs. 0.1433, respectively). The presence of microsatellite in the NTS region leading to variation in spacer length is reported and discussed for the first time in P. deltoides.

An exploration of risk for recurrent falls in two geriatric care settings

PubMed Central

2013-01-01

Background Fall events were examined in two distinct geriatric populations to identify factors associated with repeat fallers, and to examine whether patients who use gait aids, specifically a walker, were more likely to experience repeat falls. Each unit already had a generic program for falls prevention in place. Methods Secondary data analysis was conducted on information collected during the pilot testing of a new quality assurance Incident Reporting Tool between October 2006 and September 2008. The study settings included an in-patient geriatric rehabilitation unit (GRU) and a long stay veterans’ unit (LSVU) in a rehabilitation and long-stay hospital in Ontario. Participants were two hundred and twenty three individuals, aged 65 years or older on these two units, who experienced one or more fall incidents during the study period. Results Logistic regression analyses showed that on the GRU age was significantly associated with repeat falls. On the LSVU first falls in the morning or late evening were associated with repeat falling. Walker as a gait aid listed at time of first fall was not associated with repeat falls. Conclusions This study suggests that different intervention may be necessary in different geriatric settings to identify, for secondary prevention, certain individuals for which the generic programs prove inadequate. Information collection with a specific focus on the issue of repeat falls may be necessary for greater insight. PMID:24106879

High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation

NASA Astrophysics Data System (ADS)

Dimzon, Ian Ken; Trier, Xenia; Frömel, Tobias; Helmus, Rick; Knepper, Thomas P.; de Voogt, Pim

2016-02-01

High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid of an instrument data processor. Highly accurate mass spectral data enabled the calculation of higher-order mass defects. The different plots of MW and the nth-order mass defects (up to n = 3) could aid in assessing the structure of the different repeating units and estimating their absolute and relative number per molecule. The three major repeating units were -C2H4O-, -C2F4O-, and -CF2O-. Tandem MS was used to identify the end groups that appeared to be phosphates, as well as the possible distribution of the repeating units. Reversed-phase HPLC separated of the polymer molecules on the basis of number of nonpolar repeating units. The elucidated structure resembles the structure in the published manufacturer technical data. This analytical approach to the characterization of a PFPE-based formulation can serve as a guide in analyzing not just other PFPE-based formulations but also other fluorinated and non-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health.

High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation.

PubMed

Dimzon, Ian Ken; Trier, Xenia; Frömel, Tobias; Helmus, Rick; Knepper, Thomas P; de Voogt, Pim

2016-02-01

High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid of an instrument data processor. Highly accurate mass spectral data enabled the calculation of higher-order mass defects. The different plots of MW and the nth-order mass defects (up to n = 3) could aid in assessing the structure of the different repeating units and estimating their absolute and relative number per molecule. The three major repeating units were -C2H4O-, -C2F4O-, and -CF2O-. Tandem MS was used to identify the end groups that appeared to be phosphates, as well as the possible distribution of the repeating units. Reversed-phase HPLC separated of the polymer molecules on the basis of number of nonpolar repeating units. The elucidated structure resembles the structure in the published manufacturer technical data. This analytical approach to the characterization of a PFPE-based formulation can serve as a guide in analyzing not just other PFPE-based formulations but also other fluorinated and non-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health. Graphical Abstract ᅟ.

Organometallic macromolecules with piano stool coordination repeating units: chain configuration and stimulated solution behaviour.

PubMed

Cao, Kai; Ward, Jonathan; Amos, Ryan C; Jeong, Moon Gon; Kim, Kyoung Taek; Gauthier, Mario; Foucher, Daniel; Wang, Xiaosong

2014-09-11

Theoretical calculations illustrate that organometallic macromolecules with piano stool coordination repeating units (Fe-acyl complex) adopt linear chain configuration with a P-Fe-C backbone surrounded by aromatic groups. The macromolecules show molecular weight-dependent and temperature stimulated solution behaviour in DMSO.

Basic Electronics I.

ERIC Educational Resources Information Center

Robertson, L. Paul

Designed for use in basic electronics programs, this curriculum guide is comprised of twenty-nine units of instruction in five major content areas: Orientation, Basic Principles of Electricity/Electronics, Fundamentals of Direct Current, Fundamentals of Alternating Current, and Applying for a Job. Each instructional unit includes some or all of…

Designing occupancy studies: general advice and allocating survey effort

USGS Publications Warehouse

MacKenzie, D.I.; Royle, J. Andrew

2005-01-01

1. The fraction of sampling units in a landscape where a target species is present (occupancy) is an extensively used concept in ecology. Yet in many applications the species will not always be detected in a sampling unit even when present, resulting in biased estimates of occupancy. Given that sampling units are surveyed repeatedly within a relatively short timeframe, a number of similar methods have now been developed to provide unbiased occupancy estimates. However, practical guidance on the efficient design of occupancy studies has been lacking. 2. In this paper we comment on a number of general issues related to designing occupancy studies, including the need for clear objectives that are explicitly linked to science or management, selection of sampling units, timing of repeat surveys and allocation of survey effort. Advice on the number of repeat surveys per sampling unit is considered in terms of the variance of the occupancy estimator, for three possible study designs. 3. We recommend that sampling units should be surveyed a minimum of three times when detection probability is high (> 0.5 survey-1), unless a removal design is used. 4. We found that an optimal removal design will generally be the most efficient, but we suggest it may be less robust to assumption violations than a standard design. 5. Our results suggest that for a rare species it is more efficient to survey more sampling units less intensively, while for a common species fewer sampling units should be surveyed more intensively. 6. Synthesis and applications. Reliable inferences can only result from quality data. To make the best use of logistical resources, study objectives must be clearly defined; sampling units must be selected, and repeated surveys timed appropriately; and a sufficient number of repeated surveys must be conducted. Failure to do so may compromise the integrity of the study. The guidance given here on study design issues is particularly applicable to studies of species occurrence and distribution, habitat selection and modelling, metapopulation studies and monitoring programmes.

Optimum periodicity of repeated contractile actions applied in mass transport

NASA Astrophysics Data System (ADS)

Ahn, Sungsook; Lee, Sang Joon

2015-01-01

Dynamically repeated periodic patterns are abundant in natural and artificial systems, such as tides, heart beats, stock prices, and the like. The characteristic repeatability and periodicity are expected to be optimized in effective system-specific functions. In this study, such optimum periodicity is experimentally evaluated in terms of effective mass transport using one-valve and multi-valve systems working in contractile fluid flows. A set of nanoscale gating functions is utilized, operating in nanocomposite networks through which permeates selectively pass under characteristic contractile actions. Optimized contractile periodicity exists for effective energy impartment to flow in a one-valve system. In the sequential contractile actions for a multi-valve system, synchronization with the fluid flow is critical for effective mass transport. This study provides fundamental understanding on the various repeated periodic patterns and dynamic repeatability occurring in nature and mechanical systems, which are useful for broad applications.

Topological characteristics of helical repeat proteins.

PubMed

Groves, M R; Barford, D

1999-06-01

The recent elucidation of protein structures based upon repeating amino acid motifs, including the armadillo motif, the HEAT motif and tetratricopeptide repeats, reveals that they belong to the class of helical repeat proteins. These proteins share the common property of being assembled from tandem repeats of an alpha-helical structural unit, creating extended superhelical structures that are ideally suited to create a protein recognition interface.

Structural Basis of Egg Coat-Sperm Recognition at Fertilization.

PubMed

Raj, Isha; Sadat Al Hosseini, Hamed; Dioguardi, Elisa; Nishimura, Kaoru; Han, Ling; Villa, Alessandra; de Sanctis, Daniele; Jovine, Luca

2017-06-15

Recognition between sperm and the egg surface marks the beginning of life in all sexually reproducing organisms. This fundamental biological event depends on the species-specific interaction between rapidly evolving counterpart molecules on the gametes. We report biochemical, crystallographic, and mutational studies of domain repeats 1-3 of invertebrate egg coat protein VERL and their interaction with cognate sperm protein lysin. VERL repeats fold like the functionally essential N-terminal repeat of mammalian sperm receptor ZP2, whose structure is also described here. Whereas sequence-divergent repeat 1 does not bind lysin, repeat 3 binds it non-species specifically via a high-affinity, largely hydrophobic interface. Due to its intermediate binding affinity, repeat 2 selectively interacts with lysin from the same species. Exposure of a highly positively charged surface of VERL-bound lysin suggests that complex formation both disrupts the organization of egg coat filaments and triggers their electrostatic repulsion, thereby opening a hole for sperm penetration and fusion. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Effects of electronics, aromaticity, and solvent polarity on the rate of azaquinone-methide-mediated depolymerization of aromatic carbamate oligomers.

PubMed

Robbins, Jessica S; Schmid, Kyle M; Phillips, Scott T

2013-04-05

This paper uses physical-organic studies on well-defined oligomers to establish design principles for creating aromatic poly(carbamates) that depolymerize from head-to-tail in low dielectric constant environments when exposed to specific applied signals. We show that either increasing electron density or decreasing the aromaticity of aromatic repeating units in poly(carbamates) increase the overall depolymerization rate. For example, a methoxybenzene-based repeating unit provides depolymerization rates that are 143× faster than oligomers that contain a benzene-based repeating unit. Furthermore, the rate of depolymerization in the methoxybenzene-based system is tolerant to low dielectric environments, whereas the benzene-based oligomers are not.

Fundamental rate-loss tradeoff for optical quantum key distribution.

PubMed

Takeoka, Masahiro; Guha, Saikat; Wilde, Mark M

2014-10-24

Since 1984, various optical quantum key distribution (QKD) protocols have been proposed and examined. In all of them, the rate of secret key generation decays exponentially with distance. A natural and fundamental question is then whether there are yet-to-be discovered optical QKD protocols (without quantum repeaters) that could circumvent this rate-distance tradeoff. This paper provides a major step towards answering this question. Here we show that the secret key agreement capacity of a lossy and noisy optical channel assisted by unlimited two-way public classical communication is limited by an upper bound that is solely a function of the channel loss, regardless of how much optical power the protocol may use. Our result has major implications for understanding the secret key agreement capacity of optical channels-a long-standing open problem in optical quantum information theory-and strongly suggests a real need for quantum repeaters to perform QKD at high rates over long distances.

The Nature of Hololignin

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

Meng, Xianzhi; Pu, Yunqiao; Sannigrahi, Poulomi

Acid chlorite delignification is frequently used to obtain a mixture of cellulose and hemicellulose known as holocellulose from biomass. While a majority of lignin is removed after holocellulose pulping, there appears to be a minor fraction of lignin that is more resistant to acid chlorite treatment and remains in the holocellulose even after repeated delignification treatment. This type of lignin, defined as hololignin, has not been characterized, is likely to contribute to biomass recalcitrance and is clearly of fundamental interest to understand its structural characteristics. In this study, hololignin isolated from poplar holocellulose was characterized with a wide array ofmore » techniques including GPC, quantitative 13C, DEPT-135, HSQC, and 31P NMR. The results were then compared to those from milled wood lignin (MWL), the representative native lignin isolated from poplar. NMR analysis demonstrated a depletion of cinnamyl aldehyde, acetyl group, and decrease of p-hydroxybenzoate structural units in hololignin. An enrichment of condensed structures in hololignin was observed. Hololignin also had a significantly lower molecular weight than MWL. Finally, hololignin is relatively enriched in guaiacyl units and has a lower S/G ratio, lower β-O-4 ether linkages, fewer aliphatic and phenolic hydroxyl groups, and more carboxylic acid groups than MWL.« less

The Nature of Hololignin

DOE PAGES

Meng, Xianzhi; Pu, Yunqiao; Sannigrahi, Poulomi; ...

2017-11-07

Acid chlorite delignification is frequently used to obtain a mixture of cellulose and hemicellulose known as holocellulose from biomass. While a majority of lignin is removed after holocellulose pulping, there appears to be a minor fraction of lignin that is more resistant to acid chlorite treatment and remains in the holocellulose even after repeated delignification treatment. This type of lignin, defined as hololignin, has not been characterized, is likely to contribute to biomass recalcitrance and is clearly of fundamental interest to understand its structural characteristics. In this study, hololignin isolated from poplar holocellulose was characterized with a wide array ofmore » techniques including GPC, quantitative 13C, DEPT-135, HSQC, and 31P NMR. The results were then compared to those from milled wood lignin (MWL), the representative native lignin isolated from poplar. NMR analysis demonstrated a depletion of cinnamyl aldehyde, acetyl group, and decrease of p-hydroxybenzoate structural units in hololignin. An enrichment of condensed structures in hololignin was observed. Hololignin also had a significantly lower molecular weight than MWL. Finally, hololignin is relatively enriched in guaiacyl units and has a lower S/G ratio, lower β-O-4 ether linkages, fewer aliphatic and phenolic hydroxyl groups, and more carboxylic acid groups than MWL.« less

Virtual laboratories: new opportunities for collaborative water science

NASA Astrophysics Data System (ADS)

Ceola, Serena; Arheimer, Berit; Bloeschl, Guenter; Baratti, Emanuele; Capell, Rene; Castellarin, Attilio; Freer, Jim; Han, Dawei; Hrachowitz, Markus; Hundecha, Yeshewatesfa; Hutton, Christopher; Lindström, Goran; Montanari, Alberto; Nijzink, Remko; Parajka, Juraj; Toth, Elena; Viglione, Alberto; Wagener, Thorsten

2015-04-01

Reproducibility and repeatability of experiments are the fundamental prerequisites that allow researchers to validate results and share hydrological knowledge, experience and expertise in the light of global water management problems. Virtual laboratories offer new opportunities to enable these prerequisites since they allow experimenters to share data, tools and pre-defined experimental procedures (i.e. protocols). Here we present the outcomes of a first collaborative numerical experiment undertaken by five different international research groups in a virtual laboratory to address the key issues of reproducibility and repeatability. Moving from the definition of accurate and detailed experimental protocols, a rainfall-runoff model was independently applied to 15 European catchments by the research groups and model results were collectively examined through a web-based discussion. We found that a detailed modelling protocol was crucial to ensure the comparability and reproducibility of the proposed experiment across groups. Our results suggest that sharing comprehensive and precise protocols and running the experiments within a controlled environment (e.g. virtual laboratory) is as fundamental as sharing data and tools for ensuring experiment repeatability and reproducibility across the broad scientific community and thus advancing hydrology in a more coherent way.

Structural investigation of the exopolysaccharide produced by Pseudomonas flavescens strain B62--degradation by a fungal cellulase and isolation of the oligosaccharide repeating unit.

PubMed

Cescutti, P; Toffanin, R; Fett, W F; Osman, S F; Pollesello, P; Paoletti, S

1998-02-01

Pseudomonas flavescens strain B62 (NCPPB 3063) is a recently described bacterium isolated from walnut blight cankers. This strain has been designated as the type strain of a Pseudomonas rRNA group-I species. Strain B62 produced a mixture of two exopolysaccharides, differing in weight average relative molecular mass and composition. Only the most abundant exopolysaccharide (90% by mass), corresponding to the one with the lower molecular mass, was investigated by use of methylation analysis, partial acid hydrolysis, and NMR spectroscopy. The polysaccharide was depolymerised by the action of the cellulase produced by Penicillum funiculosum and the oligosaccharide obtained, corresponding to the repeating unit, was characterised by NMR spectroscopy and ion-spray mass spectrometry. The repeating unit of the B62 exopolysaccharide is [structure in text] where X is glucose (75%) or mannose (25%), and Lac is lactate. The O-acetyl groups are present only on 75% of the repeating units, and they are linked to the C6 of the hexose residues in non-stoichiometric amounts.

Dancing together and separate again: gymnosperms exhibit frequent changes of fundamental 5S and 35S rRNA gene (rDNA) organisation

PubMed Central

Garcia, S; Kovařík, A

2013-01-01

In higher eukaryotes, the 5S rRNA genes occur in tandem units and are arranged either separately (S-type arrangement) or linked to other repeated genes, in most cases to rDNA locus encoding 18S–5.8S–26S genes (L-type arrangement). Here we used Southern blot hybridisation, PCR and sequencing approaches to analyse genomic organisation of rRNA genes in all large gymnosperm groups, including Coniferales, Ginkgoales, Gnetales and Cycadales. The data are provided for 27 species (21 genera). The 5S units linked to the 35S rDNA units occur in some but not all Gnetales, Coniferales and in Ginkgo (∼30% of the species analysed), while the remaining exhibit separate organisation. The linked 5S rRNA genes may occur as single-copy insertions or as short tandems embedded in the 26S–18S rDNA intergenic spacer (IGS). The 5S transcript may be encoded by the same (Ginkgo, Ephedra) or opposite (Podocarpus) DNA strand as the 18S–5.8S–26S genes. In addition, pseudogenised 5S copies were also found in some IGS types. Both L- and S-type units have been largely homogenised across the genomes. Phylogenetic relationships based on the comparison of 5S coding sequences suggest that the 5S genes independently inserted IGS at least three times in the course of gymnosperm evolution. Frequent transpositions and rearrangements of basic units indicate relatively relaxed selection pressures imposed on genomic organisation of 5S genes in plants. PMID:23512008

Dancing together and separate again: gymnosperms exhibit frequent changes of fundamental 5S and 35S rRNA gene (rDNA) organisation.

PubMed

Garcia, S; Kovařík, A

2013-07-01

In higher eukaryotes, the 5S rRNA genes occur in tandem units and are arranged either separately (S-type arrangement) or linked to other repeated genes, in most cases to rDNA locus encoding 18S-5.8S-26S genes (L-type arrangement). Here we used Southern blot hybridisation, PCR and sequencing approaches to analyse genomic organisation of rRNA genes in all large gymnosperm groups, including Coniferales, Ginkgoales, Gnetales and Cycadales. The data are provided for 27 species (21 genera). The 5S units linked to the 35S rDNA units occur in some but not all Gnetales, Coniferales and in Ginkgo (∼30% of the species analysed), while the remaining exhibit separate organisation. The linked 5S rRNA genes may occur as single-copy insertions or as short tandems embedded in the 26S-18S rDNA intergenic spacer (IGS). The 5S transcript may be encoded by the same (Ginkgo, Ephedra) or opposite (Podocarpus) DNA strand as the 18S-5.8S-26S genes. In addition, pseudogenised 5S copies were also found in some IGS types. Both L- and S-type units have been largely homogenised across the genomes. Phylogenetic relationships based on the comparison of 5S coding sequences suggest that the 5S genes independently inserted IGS at least three times in the course of gymnosperm evolution. Frequent transpositions and rearrangements of basic units indicate relatively relaxed selection pressures imposed on genomic organisation of 5S genes in plants.

Synthesis, electronic structure, molecular packing/morphology evolution, and carrier mobilities of pure oligo-/poly(alkylthiophenes).

PubMed

Zhang, Lei; Colella, Nicholas S; Liu, Feng; Trahan, Stephan; Baral, Jayanta K; Winter, H Henning; Mannsfeld, Stefan C B; Briseno, Alejandro L

2013-01-16

Monodispersed conjugated oligothiophenes are receiving attention in fundamental and applied science due to their interesting optical, optoelectronic, and charge transport properties. These "low molecular weight" polymers serve as model structures for the corresponding polymer analogues, which are inherently polydispersed. Here we report the synthesis, electronic structure, molecular packing/morphology, and charge transport properties of monodispersed oligothiophenes with up to six didodecylquaterthiophene (DDQT) building block repeat units (i.e., 24 thiophene units). At the point where the effective conjugation length is reached, the electronic structure showed convergence behavior to the corresponding polymer, poly(3,3"-didodecyl-quaterthiophene) (PQT-12). X-ray crystal structure analysis of the dimer (DDQT-2) showed that terminal thiophenes exhibit syn-conformations, similar to the terminal syn-conformations observed in the trimer (DDQT-3). The dimer also exhibits a rare bending of the terminal alkyl side chains in order to prevent steric hindrance with neighboring hydrogens attached to core thiophenes. Grazing incidence X-ray scattering measurements revealed a morphology evolution from small molecule-like packing to polymer-like packing in thin films, with a morphology transition occurring near the effective conjugation length. Charge transport measurements showed a mobility increase with decreasing chain length. We correlated the molecular packing and morphology to charge transport and determined that carrier mobilities are most sensitive to crystallinity and crystal grain misorientation. This indicates that molecular weight is not a decisive factor for improved carrier mobility in the low molecular weight region, but rather the degree in crystallinity and in-plane crystal orientation. These results represent a fundamental advancement in understanding the relationship between conjugation length and carrier mobilities in oligothiophene semiconductors.

Amino acid sequence analysis of the annexin super-gene family of proteins.

PubMed

Barton, G J; Newman, R H; Freemont, P S; Crumpton, M J

1991-06-15

The annexins are a widespread family of calcium-dependent membrane-binding proteins. No common function has been identified for the family and, until recently, no crystallographic data existed for an annexin. In this paper we draw together 22 available annexin sequences consisting of 88 similar repeat units, and apply the techniques of multiple sequence alignment, pattern matching, secondary structure prediction and conservation analysis to the characterisation of the molecules. The analysis clearly shows that the repeats cluster into four distinct families and that greatest variation occurs within the repeat 3 units. Multiple alignment of the 88 repeats shows amino acids with conserved physicochemical properties at 22 positions, with only Gly at position 23 being absolutely conserved in all repeats. Secondary structure prediction techniques identify five conserved helices in each repeat unit and patterns of conserved hydrophobic amino acids are consistent with one face of a helix packing against the protein core in predicted helices a, c, d, e. Helix b is generally hydrophobic in all repeats, but contains a striking pattern of repeat-specific residue conservation at position 31, with Arg in repeats 4 and Glu in repeats 2, but unconserved amino acids in repeats 1 and 3. This suggests repeats 2 and 4 may interact via a buried saltbridge. The loop between predicted helices a and b of repeat 3 shows features distinct from the equivalent loop in repeats 1, 2 and 4, suggesting an important structural and/or functional role for this region. No compelling evidence emerges from this study for uteroglobin and the annexins sharing similar tertiary structures, or for uteroglobin representing a derivative of a primordial one-repeat structure that underwent duplication to give the present day annexins. The analyses performed in this paper are re-evaluated in the Appendix, in the light of the recently published X-ray structure for human annexin V. The structure confirms most of the predictions and shows the power of techniques for the determination of tertiary structural information from the amino acid sequences of an aligned protein family.

Evidence-Based Kernels: Fundamental Units of Behavioral Influence

ERIC Educational Resources Information Center

Embry, Dennis D.; Biglan, Anthony

2008-01-01

This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior-influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of…

Population-scale whole genome sequencing identifies 271 highly polymorphic short tandem repeats from Japanese population.

PubMed

Hirata, Satoshi; Kojima, Kaname; Misawa, Kazuharu; Gervais, Olivier; Kawai, Yosuke; Nagasaki, Masao

2018-05-01

Forensic DNA typing is widely used to identify missing persons and plays a central role in forensic profiling. DNA typing usually uses capillary electrophoresis fragment analysis of PCR amplification products to detect the length of short tandem repeat (STR) markers. Here, we analyzed whole genome data from 1,070 Japanese individuals generated using massively parallel short-read sequencing of 162 paired-end bases. We have analyzed 843,473 STR loci with two to six basepair repeat units and cataloged highly polymorphic STR loci in the Japanese population. To evaluate the performance of the cataloged STR loci, we compared 23 STR loci, widely used in forensic DNA typing, with capillary electrophoresis based STR genotyping results in the Japanese population. Seventeen loci had high correlations and high call rates. The other six loci had low call rates or low correlations due to either the limitations of short-read sequencing technology, the bioinformatics tool used, or the complexity of repeat patterns. With these analyses, we have also purified the suitable 218 STR loci with four basepair repeat units and 53 loci with five basepair repeat units both for short read sequencing and PCR based technologies, which would be candidates to the actual forensic DNA typing in Japanese population.

Avogadro's Number Ferromagnetically

ERIC Educational Resources Information Center

Houari, Ahmed

2010-01-01

Avogadro's number, usually denoted by N[subscript A], plays a fundamental role in both physics and chemistry. It defines the extremely useful concept of the mole, which is the base unit of the amount of matter in the international system of units. The fundamental character of this number can also be illustrated by its appearance in the definitions…

How fundamental are fundamental constants?

NASA Astrophysics Data System (ADS)

Duff, M. J.

2015-01-01

I argue that the laws of physics should be independent of one's choice of units or measuring apparatus. This is the case if they are framed in terms of dimensionless numbers such as the fine structure constant, ?. For example, the standard model of particle physics has 19 such dimensionless parameters whose values all observers can agree on, irrespective of what clock, rulers or scales? they use to measure them. Dimensional constants, on the other hand, such as ?, c, G, e and k ?, are merely human constructs whose number and values differ from one choice of units to the next. In this sense, only dimensionless constants are 'fundamental'. Similarly, the possible time variation of dimensionless fundamental 'constants' of nature is operationally well defined and a legitimate subject of physical enquiry. By contrast, the time variation of dimensional constants such as ? or ? on which a good many (in my opinion, confusing) papers have been written, is a unit-dependent phenomenon on which different observers might disagree depending on their apparatus. All these confusions disappear if one asks only unit-independent questions. We provide a selection of opposing opinions in the literature and respond accordingly.

Concise chemical synthesis of a tetrasaccharide repeating unit of the O-antigen of Hafnia alvei 10457.

PubMed

Kumar, Rishi; Maulik, Prakas R; Misra, Anup Kumar

2008-08-01

Concise chemical synthesis of a tetrasaccharide repeating unit of the O-antigen of Hafnia alvei 10457 is reported. Construction of the tetrasaccharide as its 4-methoxyphenyl glycoside was achieved by condensation of less abundant monosaccharide units such as, D-galactofuranose, N-acetyl-D-galactosamine and N-acetylneuraminic acid. The synthetic strategy consists of the preparation of suitably protected required monosaccharide intermediates from the commercially available reducing sugars and high yielding glycosylation reactions.

Genetic Studies of the Prp17 Gene of Saccharomyces Cerevisiae: A Domain Essential for Function Maps to a Nonconserved Region of the Protein

PubMed Central

Seshadri, V.; Vaidya, V. C.; Vijayraghavan, U.

1996-01-01

The PRP17 gene product is required for the second step of pre-mRNA splicing reactions. The C-terminal half of this protein bears four repeat units with homology to the β transducin repeat. Missense mutations in three temperature-sensitive prp17 mutants map to a region in the N-terminal half of the protein. We have generated, in vitro, 11 missense alleles at the β transducin repeat units and find that only one affects function in vivo. A phenotypically silent missense allele at the fourth repeat unit enhances the slow-growing phenotype conferred by an allele at the third repeat, suggesting an interaction between these domains. Although many missense mutations in highly conserved amino acids lack phenotypic effects, deletion analysis suggests an essential role for these units. Only mutations in the N-terminal nonconserved domain of PRP17 are synthetically lethal in combination with mutations in PRP16 and PRP18, two other gene products required for the second splicing reaction. A mutually allele-specific interaction between prp17 and snr7, with mutations in U5 snRNA, was observed. We therefore suggest that the functional region of Prp17p that interacts with Prp18p, Prp16p, and U5 snRNA is in the N terminal region of the protein. PMID:8722761

Assessment of The Stability of The H/v Spectral Ratio of Ambient Noise and Comparison With Earthquake Data In The Cologne Area (germany)

NASA Astrophysics Data System (ADS)

Parolai, S.; Richwalski, S. M.; Milkereit, C.; Bormann, P.

Situated in an active tectonic region the highly industrialised Cologne area (Germany) suffers from moderate sized earthquakes. The mitigation of earthquake risk included a microzonation study with ambient seismic noise and earthquake recordings in two field campaigns. The analysis of the ambient noise data using the horizontal-to-vertical (H/V) spectral ratio allowed for mapping the fundamental resonance frequency of soils in this area. Furthermore, adding independent geological information we calculated new relationships between shear-wave velocity, sediment thickness, and resonance frequency. The stability of the H/V ratio of ambient noise was checked with repeated measurements and the following observations and conclusions can be drawn: (1) The fundamental resonance frequency estimated from the peak in the H/V ratio is stable in time but the amplification factor is not. (2) Therefore, the relative amplification vari- ation in the area should be checked systematically with repeated measurements. (3) The thickness of the sediments is reliably retrieved from the fundamental resonance frequency. The H/V ratio of ambient noise recordings was compared with the H/V ratio of earth- quake recordings as well as with the curves obtained by applying the classical spectral ratio technique (using a reference site). The shapes of the spectral ratios obtained by the different methods are generally in good agreement.In addition, the analysis of earthquake data shows that significant amplifications of the ground motion may also occur at frequencies higher than the fundamental one.

Plant chromosomes from end to end: telomeres, heterochromatin and centromeres.

PubMed

Lamb, Jonathan C; Yu, Weichang; Han, Fangpu; Birchler, James A

2007-04-01

Recent evidence indicates that heterochromatin in plants is composed of heterogeneous sequences, which are usually composed of transposable elements or tandem repeat arrays. These arrays are associated with chromatin modifications that produce a closed configuration that limits transcription. Centromere sequences in plants are usually composed of tandem repeat arrays that are homogenized across the genome. Analysis of such arrays in closely related taxa suggests a rapid turnover of the repeat unit that is typical of a particular species. In addition, two lines of evidence for an epigenetic component of centromere specification have been reported, namely an example of a neocentromere formed over sequences without the typical repeat array and examples of centromere inactivation. Although the telomere repeat unit is quite prevalent in the plant kingdom, unusual repeats have been found in some families. Recently, it was demonstrated that the introduction of telomere sequences into plants cells causes truncation of the chromosomes, and that this technique can be used to produce artificial chromosome platforms.

The structure of the exopolysaccharide of Pseudomonas fluorescens strain H13.

PubMed

Osman, S F; Fett, W F; Irwin, P; Cescutti, P; Brouillette, J N; O'Connor, J V

1997-05-19

An acidic exopolysaccharide was isolated from P. fluorescens strain H13. The structure of the polysaccharide repeating unit was determined using chemical methods and 1D and 2D NMR techniques. The repeating unit was characterized as a trisaccharide composed of D-glucose, 2-acetamido-2-deoxy-D-glucose and 4-O-acetyl-2-acetamido-2-deoxy-D-mannuronic acid.

A Simple Method to Decode the Complete 18-5.8-28S rRNA Repeated Units of Green Algae by Genome Skimming.

PubMed

Lin, Geng-Ming; Lai, Yu-Heng; Audira, Gilbert; Hsiao, Chung-Der

2017-11-06

Green algae, Chlorella ellipsoidea , Haematococcus pluvialis and Aegagropila linnaei (Phylum Chlorophyta) were simultaneously decoded by a genomic skimming approach within 18-5.8-28S rRNA region. Whole genomic DNAs were isolated from green algae and directly subjected to low coverage genome skimming sequencing. After de novo assembly and mapping, the size of complete 18-5.8-28S rRNA repeated units for three green algae were ranged from 5785 to 6028 bp, which showed high nucleotide diversity (π is around 0.5-0.6) within ITS1 and ITS2 (Internal Transcribed Spacer) regions. Previously, the evolutional diversity of algae has been difficult to decode due to the inability design universal primers that amplify specific marker genes across diverse algal species. In this study, our method provided a rapid and universal approach to decode the 18-5.8-28S rRNA repeat unit in three green algal species. In addition, the completely sequenced 18-5.8-28S rRNA repeated units provided a solid nuclear marker for phylogenetic and evolutionary analysis for green algae for the first time.

Comparative Analysis of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) of Streptococcus thermophilus St-I and its Bacteriophage-Insensitive Mutants (BIM) Derivatives.

PubMed

Li, Wan; Bian, Xin; Evivie, Smith Etareri; Huo, Gui-Cheng

2016-09-01

The CRISPR-Cas (CRISPR together with CRISPR-associated proteins) modules are the adaptive immune system, acting as an adaptive and heritable immune system in bacteria and archaea. CRISPR-based immunity acts by integrating short virus sequences in the cell's CRISPR locus, allowing the cell to remember, recognize, and clear infections. In this study, the homology of CRISPRs sequence in BIMs (bacteriophage-insensitive mutants) of Streptococcus thermophilus St-I were analyzed. Secondary structures of the repeats and the PAMs (protospacer-associated motif) of each CRISPR locus were also predicted. Results showed that CRISPR1 has 27 repeat-spacer units, 5 of them had duplicates; CRISPR2 has one repeat-spacer unit; CRISPR3 has 28 repeat-spacer units. Only BIM1 had a new spacer acquisition in CRISPR3, while BIM2 and BIM3 had no new spacers' insertion, thus indicating that while most CRISPR1 were more active than CRISPR3, new spacer acquisition occurred just in CRSPR3 in some situations. These findings will help establish the foundation for the study of CRSPR-Cas systems in lactic acid bacteria.

Time Scales in the JPL and CfA Ephemerides

NASA Technical Reports Server (NTRS)

Standish, E. M.

1998-01-01

Over the past decades, the IAU has repeatedly attempted to correct its definition of the basic fundamental argument used in the emphemerides. Finally, they have defined a time system which is physically possible, according to the accepted standard theory of gravitation.

The concept of hydrologic landscapes

USGS Publications Warehouse

Winter, T.C.

2001-01-01

Hydrologic landscapes are multiples or variations of fundamental hydrologic landscape units. A fundamental hydrologic landscape unit is defined on the basis of land-surface form, geology, and climate. The basic land-surface form of a fundamental hydrologic landscape unit is an upland separated from a lowland by an intervening steeper slope. Fundamental hydrologic landscape units have a complete hydrologic system consisting of surface runoff, ground-water flow, and interaction with atmospheric water. By describing actual landscapes in terms of land-surface slope, hydraulic properties of soils and geologic framework, and the difference between precipitation and evapotranspiration, the hydrologic system of actual landscapes can be conceptualized in a uniform way. This conceptual framework can then be the foundation for design of studies and data networks, syntheses of information on local to national scales, and comparison of process research across small study units in a variety of settings. The Crow Wing River watershed in central Minnesota is used as an example of evaluating stream discharge in the context of hydrologic landscapes. Lake-research watersheds in Wisconsin, Minnesota, North Dakota, and Nebraska are used as an example of using the hydrologic-landscapes concept to evaluate the effect of ground water on the degree of mineralization and major-ion chemistry of lakes that lie within ground-water flow systems.

NIST Stars: Absolute Spectrophotometric Calibration of Vega and Sirius

NASA Astrophysics Data System (ADS)

Deustua, Susana; Woodward, John T.; Rice, Joseph P.; Brown, Steven W.; Maxwell, Stephen E.; Alberding, Brian G.; Lykke, Keith R.

2018-01-01

Absolute flux calibration of standard stars, traceable to SI (International System of Units) standards, is essential for 21st century astrophysics. Dark energy investigations that rely on observations of Type Ia supernovae and precise photometric redshifts of weakly lensed galaxies require a minimum accuracy of 0.5 % in the absolute color calibration. Studies that aim to address fundamental stellar astrophysics also benefit. In the era of large telescopes and all sky surveys well-calibrated standard stars that do not saturate and that are available over the whole sky are needed. Significant effort has been expended to obtain absolute measurements of the fundamental standards Vega and Sirius (and other stars) in the visible and near infrared, achieving total uncertainties between1% and 3%, depending on wavelength, that do not meet the needed accuracy. The NIST Stars program aims to determine the top-of-the-atmosphere absolute spectral irradiance of bright stars to an uncertainty less than 1% from a ground-based observatory. NIST Stars has developed a novel, fully SI-traceable laboratory calibration strategy that will enable achieving the desired accuracy. This strategy has two key components. The first is the SI-traceable calibration of the entire instrument system, and the second is the repeated spectroscopic measurement of the target star throughout the night. We will describe our experimental strategy, present preliminary results for Vega and Sirius and an end-to-end uncertainty budget

Parameter regimes for a single sequential quantum repeater

NASA Astrophysics Data System (ADS)

Rozpędek, F.; Goodenough, K.; Ribeiro, J.; Kalb, N.; Caprara Vivoli, V.; Reiserer, A.; Hanson, R.; Wehner, S.; Elkouss, D.

2018-07-01

Quantum key distribution allows for the generation of a secret key between distant parties connected by a quantum channel such as optical fibre or free space. Unfortunately, the rate of generation of a secret key by direct transmission is fundamentally limited by the distance. This limit can be overcome by the implementation of so-called quantum repeaters. Here, we assess the performance of a specific but very natural setup called a single sequential repeater for quantum key distribution. We offer a fine-grained assessment of the repeater by introducing a series of benchmarks. The benchmarks, which should be surpassed to claim a working repeater, are based on finite-energy considerations, thermal noise and the losses in the setup. In order to boost the performance of the studied repeaters we introduce two methods. The first one corresponds to the concept of a cut-off, which reduces the effect of decoherence during the storage of a quantum state by introducing a maximum storage time. Secondly, we supplement the standard classical post-processing with an advantage distillation procedure. Using these methods, we find realistic parameters for which it is possible to achieve rates greater than each of the benchmarks, guiding the way towards implementing quantum repeaters.

48 CFR 9904.420-40 - Fundamental requirement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Fundamental requirement..., OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.420-40 Fundamental requirement. (a) The basic unit for...

48 CFR 9904.410-40 - Fundamental requirement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Fundamental requirement..., OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.410-40 Fundamental requirement. (a) Business unit G&A...

48 CFR 9904.418-40 - Fundamental requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Fundamental requirements..., OFFICE OF FEDERAL PROCUREMENT POLICY, OFFICE OF MANAGEMENT AND BUDGET PROCUREMENT PRACTICES AND COST ACCOUNTING STANDARDS COST ACCOUNTING STANDARDS 9904.418-40 Fundamental requirements. (a) A business unit...

CODATA Fundamental Physical Constants

National Institute of Standards and Technology Data Gateway

SRD 121 NIST CODATA Fundamental Physical Constants (Web, free access)   This site, developed in the Physics Laboratory at NIST, addresses three topics: fundamental physical constants, the International System of Units (SI), which is the modern metric system, and expressing the uncertainty of measurement results.

47 CFR 36.2 - Fundamental principles underlying procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Fundamental principles underlying procedures... Fundamental principles underlying procedures. (a) The following general principles underlie the procedures... operating forces on a unit basis (e.g., conversation-minute-kilometers per message, weighted standard work...

47 CFR 90.247 - Mobile repeater stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of the mobile unit and an automatic time-delay device that de-activates the transmitter after any... 47 Telecommunication 5 2010-10-01 2010-10-01 false Mobile repeater stations. 90.247 Section 90.247... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.247 Mobile repeater stations. A...

Limitations on quantum key repeaters.

PubMed

Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

2015-04-23

A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol.

Influence of Th2 cells on hair cycle/growth after repeated cutaneous application of hapten.

PubMed

Sugita, K; Nomura, T; Ikenouchi-Sugita, A; Ito, T; Nakamura, M; Miyachi, Y; Tokura, Y; Kabashima, K

2014-03-01

Exposure to contact allergens in order to produce allergic contact dermatitis (ACD) seems to induce hair cycle/growth, but the mechanism of this remains unclear. In the current study, we investigated this mechanism and found that repeated application of hapten induced production of interleukin (IL)-4 in lymph-node immune cells. In addition, hair growth was induced in mice after the adoptive transfer of T-helper (Th)2 cells that had been purified from mice exposed to repeated cutaneous application of hapten. These findings lead us to speculate that Th2 cells that are repeatedly hapten-sensitized are recruited to hapten-challenged skin areas, and thus stimulate the production of IL-4 in the vicinity of the hair follicles, which influences hair cycle/growth. Our results may provide fundamental insights into the mechanism of contact hypersensitivity-induced hair cycle/growth. © 2013 British Association of Dermatologists.

Adaptive Management and Monitoring as Fundamental Tools to Effective Salt Marsh Restoration

EPA Science Inventory

Adaptive management as applied to ecological restoration is a systematic decision-making process in which the results of restoration activities are repeatedly monitored and evaluated to provide guidance that can be used in determining any necessary future restoration actions. In...

Super-resolution technique for CW lidar using Fourier transform reordering and Richardson-Lucy deconvolution.

PubMed

Campbell, Joel F; Lin, Bing; Nehrir, Amin R; Harrison, F Wallace; Obland, Michael D

2014-12-15

An interpolation method is described for range measurements of high precision altimetry with repeating intensity modulated continuous wave (IM-CW) lidar waveforms using binary phase shift keying (BPSK), where the range profile is determined by means of a cross-correlation between the digital form of the transmitted signal and the digitized return signal collected by the lidar receiver. This method uses reordering of the array elements in the frequency domain to convert a repeating synthetic pulse signal to single highly interpolated pulse. This is then enhanced further using Richardson-Lucy deconvolution to greatly enhance the resolution of the pulse. We show the sampling resolution and pulse width can be enhanced by about two orders of magnitude using the signal processing algorithms presented, thus breaking the fundamental resolution limit for BPSK modulation of a particular bandwidth and bit rate. We demonstrate the usefulness of this technique for determining cloud and tree canopy thicknesses far beyond this fundamental limit in a lidar not designed for this purpose.

Discordant expression and variable numbers of neighboring GGA- and GAA-rich triplet repeats in the 3' untranslated regions of two groups of messenger RNAs encoded by the rat polymeric immunoglobulin receptor gene.

PubMed Central

Koch, K S; Gleiberman, A S; Aoki, T; Leffert, H L; Feren, A; Jones, A L; Fodor, E J

1995-01-01

An unusual S1-nuclease sensitive microsatellite (STMS) has been found in the single copy, rat polymeric immunoglobulin receptor gene (PIGR) terminal exon. In Fisher rats, elements within or beyond the STMS are expressed variably in the 3' untranslated regions (3'UTRs) of two 'Groups' of PIGR-encoded hepatic mRNAs (pIg-R) during liver regeneration. STMS elements include neighboring constant regions (a 60-bp d[GA]-rich tract with a chi-like octamer, followed by 15 tandem d[GGA] repeats) that merge directly with 36 or 39 tandem d[GAA] repeats (Fisher or Wistar strains, respectively) interrupted by d[AA] between their 5th-6th repeat units. The Wistar STMS is flanked upstream by two regions of nearly contiguous d[CA] or d[CT] repeats in the 3' end of intron 8; and downstream, by a 283 bp 'unit' containing several inversions at its 5' end, and two polyadenylation signals at its 3' end. The 283 nt unit is expressed in Group 1 pIg-R mRNAs; but it is absent in the Group 2 family so that their GAA repeats merge with their poly A tails. In contrast to genomic sequence, GGA triplet repeats are amplified (n > or = 24-26), whereas GAA triplet repeats are truncated variably (n < or = 9-37) and expressed uninterruptedly in both mRNA Groups. These results suggest that 3' end processing of the rat PIGR gene may involve misalignment, slippage and premature termination of RNA polymerase II. The function of this unusual processing and possible roles of chi-like octamers in quiescent or extrahepatic tissues are discussed. Images PMID:7739889

High Regional Variation in Urethroplasty in the United States

PubMed Central

Figler, Bradley D.; Gore, John L.; Holt, Sarah K.; Voelzke, Bryan B.; Wessells, Hunter

2015-01-01

Purpose We identified clinical and regional factors associated with the use of urethroplasty vs repeat endoscopic management for urethral stricture disease. Materials and Methods We analyzed claims for patients 18 to 65 years old in the 2007 to 2011 MarketScan ® Commercial Claims and Encounters Database with a diagnosis of urethral stricture. The primary outcome was treatment with urethroplasty vs repeat endoscopic management, defined as more than 2 dilations or direct vision internal urethrotomies. The likelihood of urethroplasty vs repeat endoscopic management was determined for each major metropolitan area in the United States. Multivariate logistic regression was done to identify factors associated with urethroplasty. Results We identified 41,056 patients with urethral stricture, yielding a diagnosis rate of 296/100,000 men in MarketScan. Repeat endoscopic management and urethroplasty were performed in 2,700 and 1,444 patients, respectively. Compared to patients treated with repeat endoscopic management those with urethroplasty were younger (median age 44 vs 54 years) and more likely to have a Charlson comorbidity score of 0 (84% vs 77%), have traveled out of a metropolitan area for care (34% vs 17%) and have a reconstructive urologist in the treatment metropolitan area (76% and 62%, each p < 0.001). When controlling for age and Charlson comorbidity score, travel out of a metropolitan area (OR 2.7, 95% CI 2.2–3.3) and a reconstructive urologist in the treatment metropolitan area (OR 2.0, 95% CI 1.7–2.5) were associated with a greater likelihood of urethroplasty vs repeat endoscopic management. Conclusions Despite the well established benefits of urethroplasty compared to repeat endoscopic management a strong bias for repeat endoscopic management exists in many regions in the United States. PMID:25072180

Solid polymeric electrolytes for lithium batteries

DOEpatents

Angell, Charles A.; Xu, Wu; Sun, Xiaoguang

2006-03-14

Novel conductive polyanionic polymers and methods for their preparion are provided. The polyanionic polymers comprise repeating units of weakly-coordinating anionic groups chemically linked to polymer chains. The polymer chains in turn comprise repeating spacer groups. Spacer groups can be chosen to be of length and structure to impart desired electrochemical and physical properties to the polymers. Preferred embodiments are prepared from precursor polymers comprising the Lewis acid borate tri-coordinated to a selected ligand and repeating spacer groups to form repeating polymer chain units. These precursor polymers are reacted with a chosen Lewis base to form a polyanionic polymer comprising weakly coordinating anionic groups spaced at chosen intervals along the polymer chain. The polyanionic polymers exhibit high conductivity and physical properties which make them suitable as solid polymeric electrolytes in lithium batteries, especially secondary lithium batteries.

Spectroscopic and molecular structure investigation of the phosphorus-containing G‧2 dendrimer with terminal aldehyde groups using DFT method

NASA Astrophysics Data System (ADS)

Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

2015-02-01

The FTIR and FT Raman spectra of the second generation dendrimer G‧2 built from thiophosphoryl core with terminal aldehyde groups have been recorded. The structural optimization and normal mode analysis were performed for model compound C, consisting of thiophosphoryl core, one branch with three repeated units, and four 4-oxybenzaldehyde terminal groups on the basis of the density functional theory (DFT) at the PBE/TZ2P level. The vibrational frequencies, infrared and Raman intensities for the t,g,g- and t,-g,g-conformers of the terminal groups were calculated. The t,g,g-conformer is 2.0 kcal/mol less stable compared to t,-g,g-conformer. A reliable assignment of the fundamental bands observed in the experimental IR and Raman spectra of dendrimer was achieved. For the low generations (G‧1 to G‧3) the disk form of studied dendrimer molecules is the most probable. For higher generations, the shape of dendrimer molecules will be that of a cauliflower.

Childhood Adversities and Adult Cardiometabolic Health: Does the Quantity, Timing, and Type of Adversity Matter?

PubMed Central

Friedman, Esther M.; Montez, Jennifer Karas; Sheehan, Connor McDevitt; Guenewald, Tara L.; Seeman, Teresa E.

2015-01-01

Objective Adverse events in childhood can indelibly influence adult health. While evidence for this association has mounted, a fundamental set of questions about how to operationalize adverse events has been understudied. Method We used data from the National Survey of Midlife Development in the United States to examine how quantity, timing, and types of adverse events in childhood are associated with adult cardiometabolic health. Results The best-fitting specification of quantity of events was a linear measure reflecting a dose–response relationship. Timing of event mattered less than repeated exposure to events. Regarding the type of event, academic interruptions and sexual/physical abuse were most important. Adverse childhood events elevated the risk of diabetes and obesity similarly for men and women but had a greater impact on women’s risk of heart disease. Discussion Findings demonstrate the insights that can be gleaned about the early-life origins of adult health by examining operationalization of childhood exposures. PMID:25903978

Ultrafast magnetization reversal by picosecond electrical pulses

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

Yang, Yang; Wilson, Richard B.; Gorchon, Jon

The field of spintronics involves the study of both spin and charge transport in solid-state devices. Ultrafast magnetism involves the use of femtosecond laser pulses to manipulate magnetic order on subpicosecond time scales. Here, we unite these phenomena by using picosecond charge current pulses to rapidly excite conduction electrons in magnetic metals. We observe deterministic, repeatable ultrafast reversal of the magnetization of a GdFeCo thin film with a single sub–10-ps electrical pulse. The magnetization reverses in ~10 ps, which is more than one order of magnitude faster than any other electrically controlled magnetic switching, and demonstrates a fundamentally new electricalmore » switching mechanism that does not require spin-polarized currents or spin-transfer/orbit torques. The energy density required for switching is low, projecting to only 4 fJ needed to switch a (20 nm) 3 cell. This discovery introduces a new field of research into ultrafast charge current–driven spintronic phenomena and devices.« less

Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry

PubMed Central

Gleason, Colin J.; Smith, Laurence C.

2014-01-01

Rivers provide critical water supply for many human societies and ecosystems, yet global knowledge of their flow rates is poor. We show that useful estimates of absolute river discharge (in cubic meters per second) may be derived solely from satellite images, with no ground-based or a priori information whatsoever. The approach works owing to discovery of a characteristic scaling law uniquely fundamental to natural rivers, here termed a river’s at-many-stations hydraulic geometry. A first demonstration using Landsat Thematic Mapper images over three rivers in the United States, Canada, and China yields absolute discharges agreeing to within 20–30% of traditional in situ gauging station measurements and good tracking of flow changes over time. Within such accuracies, the door appears open for quantifying river resources globally with repeat imaging, both retroactively and henceforth into the future, with strong implications for water resource management, food security, ecosystem studies, flood forecasting, and geopolitics. PMID:24639551

Fluctuating exciton localization in giant π-conjugated spoked-wheel macrocycles.

PubMed

Aggarwal, A Vikas; Thiessen, Alexander; Idelson, Alissa; Kalle, Daniel; Würsch, Dominik; Stangl, Thomas; Steiner, Florian; Jester, Stefan-S; Vogelsang, Jan; Höger, Sigurd; Lupton, John M

2013-11-01

Conjugated polymers offer potential for many diverse applications, but we still lack a fundamental microscopic understanding of their electronic structure. Elementary photoexcitations (excitons) span only a few nanometres of a molecule, which itself can extend over microns, and how their behaviour is affected by molecular dimensions is not immediately obvious. For example, where is the exciton formed within a conjugated segment and is it always situated on the same repeat units? Here, we introduce structurally rigid molecular spoked wheels, 6 nm in diameter, as a model of extended π conjugation. Single-molecule fluorescence reveals random exciton localization, which leads to temporally varying emission polarization. Initially, this random localization arises after every photon absorption event because of temperature-independent spontaneous symmetry breaking. These fast fluctuations are slowed to millisecond timescales after prolonged illumination. Intramolecular heterogeneity is revealed in cryogenic spectroscopy by jumps in transition energy, but emission polarization can also switch without a spectral jump occurring, which implies long-range homogeneity in the local dielectric environment.

Fluctuating exciton localization in giant π-conjugated spoked-wheel macrocycles

NASA Astrophysics Data System (ADS)

Aggarwal, A. Vikas; Thiessen, Alexander; Idelson, Alissa; Kalle, Daniel; Würsch, Dominik; Stangl, Thomas; Steiner, Florian; Jester, Stefan-S.; Vogelsang, Jan; Höger, Sigurd; Lupton, John M.

2013-11-01

Conjugated polymers offer potential for many diverse applications, but we still lack a fundamental microscopic understanding of their electronic structure. Elementary photoexcitations (excitons) span only a few nanometres of a molecule, which itself can extend over microns, and how their behaviour is affected by molecular dimensions is not immediately obvious. For example, where is the exciton formed within a conjugated segment and is it always situated on the same repeat units? Here, we introduce structurally rigid molecular spoked wheels, 6 nm in diameter, as a model of extended π conjugation. Single-molecule fluorescence reveals random exciton localization, which leads to temporally varying emission polarization. Initially, this random localization arises after every photon absorption event because of temperature-independent spontaneous symmetry breaking. These fast fluctuations are slowed to millisecond timescales after prolonged illumination. Intramolecular heterogeneity is revealed in cryogenic spectroscopy by jumps in transition energy, but emission polarization can also switch without a spectral jump occurring, which implies long-range homogeneity in the local dielectric environment.

Toward global mapping of river discharge using satellite images and at-many-stations hydraulic geometry.

PubMed

Gleason, Colin J; Smith, Laurence C

2014-04-01

Rivers provide critical water supply for many human societies and ecosystems, yet global knowledge of their flow rates is poor. We show that useful estimates of absolute river discharge (in cubic meters per second) may be derived solely from satellite images, with no ground-based or a priori information whatsoever. The approach works owing to discovery of a characteristic scaling law uniquely fundamental to natural rivers, here termed a river's at-many-stations hydraulic geometry. A first demonstration using Landsat Thematic Mapper images over three rivers in the United States, Canada, and China yields absolute discharges agreeing to within 20-30% of traditional in situ gauging station measurements and good tracking of flow changes over time. Within such accuracies, the door appears open for quantifying river resources globally with repeat imaging, both retroactively and henceforth into the future, with strong implications for water resource management, food security, ecosystem studies, flood forecasting, and geopolitics.

Ultrafast magnetization reversal by picosecond electrical pulses

DOE PAGES

Yang, Yang; Wilson, Richard B.; Gorchon, Jon; ...

2017-11-03

The field of spintronics involves the study of both spin and charge transport in solid-state devices. Ultrafast magnetism involves the use of femtosecond laser pulses to manipulate magnetic order on subpicosecond time scales. Here, we unite these phenomena by using picosecond charge current pulses to rapidly excite conduction electrons in magnetic metals. We observe deterministic, repeatable ultrafast reversal of the magnetization of a GdFeCo thin film with a single sub–10-ps electrical pulse. The magnetization reverses in ~10 ps, which is more than one order of magnitude faster than any other electrically controlled magnetic switching, and demonstrates a fundamentally new electricalmore » switching mechanism that does not require spin-polarized currents or spin-transfer/orbit torques. The energy density required for switching is low, projecting to only 4 fJ needed to switch a (20 nm) 3 cell. This discovery introduces a new field of research into ultrafast charge current–driven spintronic phenomena and devices.« less

Accurate Determination of the Values of Fundamental Physical Constants: The Basis of the New "Quantum" SI Units

NASA Astrophysics Data System (ADS)

Karshenboim, S. G.

2018-03-01

The metric system appeared as the system of units designed for macroscopic (laboratory scale) measurements. The progress in accurate determination of the values of quantum constants (such as the Planck constant) in SI units shows that the capabilities in high-precision measurement of microscopic and macroscopic quantities in terms of the same units have increased substantially recently. At the same time, relative microscopic measurements (for example, the comparison of atomic transition frequencies or atomic masses) are often much more accurate than relative measurements of macroscopic quantities. This is the basis for the strategy to define units in microscopic phenomena and then use them on the laboratory scale, which plays a crucial role in practical methodological applications determined by everyday life and technologies. The international CODATA task group on fundamental constants regularly performs an overall analysis of the precision world data (the so-called Adjustment of the Fundamental Constants) and publishes their recommended values. The most recent evaluation was based on the data published by the end of 2014; here, we review the corresponding data and results. The accuracy in determination of the Boltzmann constant has increased, the consistency of the data on determination of the Planck constant has improved; it is these two dimensional constants that will be used in near future as the basis for the new definition of the kelvin and kilogram, respectively. The contradictions in determination of the Rydberg constant and the proton charge radius remain. The accuracy of determination of the fine structure constant and relative atomic weight of the electron has improved. Overall, we give a detailed review of the state of the art in precision determination of the values of fundamental constants. The mathematical procedure of the Adjustment, the new data and results are considered in detail. The limitations due to macroscopic properties of material standards (such as the International prototype of the kilogram) and the isotopic composition of substances involved in precision studies in general (as standard measures for the triple point of water) and, in particular, in the determination of the fundamental constants are discussed. The perspectives of the introduction of the new quantum units, which will be free from the mentioned problems, are considered. Many physicists feel no sympathy for the International system of units (SI), believing that it does not properly reflect the character of physical laws. In fact, there are three parallel systems, namely the systems of quantities, system of their units and the related standards. The definition of the units, in particular, the SI units, above all, reflects our ability to perform precision measurements of physical values under certain conditions, in particular, to create appropriate standards. This requirement is not related to the beauty of fundamental laws of nature. More accurate determination of the fundamental constants is one of the areas where we accumulate such experience.

Novel variants of the 5S rRNA genes in Eruca sativa.

PubMed

Singh, K; Bhatia, S; Lakshmikumaran, M

1994-02-01

The 5S ribosomal RNA (rRNA) genes of Eruca sativa were cloned and characterized. They are organized into clusters of tandemly repeated units. Each repeat unit consists of a 119-bp coding region followed by a noncoding spacer region that separates it from the coding region of the next repeat unit. Our study reports novel gene variants of the 5S rRNA genes in plants. Two families of the 5S rDNA, the 0.5-kb size family and the 1-kb size family, coexist in the E. sativa genome. The 0.5-kb size family consists of the 5S rRNA genes (S4) that have coding regions similar to those of other reported plant 5S rDNA sequences, whereas the 1-kb size family consists of the 5S rRNA gene variants (S1) that exist as 1-kb BamHI tandem repeats. S1 is made up of two variant units (V1 and V2) of 5S rDNA where the BamHI site between the two units is mutated. Sequence heterogeneity among S4, V1, and V2 units exists throughout the sequence and is not limited to the noncoding spacer region only. The coding regions of V1 and V2 show approximately 20% dissimilarity to the coding regions of S4 and other reported plant 5S rDNA sequences. Such a large variation in the coding regions of the 5S rDNA units within the same plant species has been observed for the first time. Restriction site variation is observed between the two size classes of 5S rDNA in E. sativa.(ABSTRACT TRUNCATED AT 250 WORDS)

Repeating Patterns in Kindergarten: Findings from Children's Enactments of Two Activities

ERIC Educational Resources Information Center

Tsamir, Pessia; Tirosh, Dina; Levenson, Esther S.; Barkai, Ruthi; Tabach, Michal

2017-01-01

This paper describes kindergarten children's engagement with two patterning activities. The first activity includes two tasks in which children are asked to choose possible ways for extending two different repeating patterns and the second activity calls for comparing different pairs of repeating patterns. Children's recognition of the unit of…

Interactive fundamental physics. [THE REAL STUFF: The New Expanded Media Physics Course for secondary school students

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

Rubin, E.L.

THE REAL STUFF is an Expanded Media Physics Course aimed at students still in the formative early years of secondary school. Its consists of a working script for an interactive multimedia study unit in basic concepts of physics. The unit begins with a prologue on the Big Bang that sets the stage, and concludes with a lesson on Newton's first law of motion. The format is interactive, placing the individual student in control of a layered hypermedia'' structure that enables him or her to find a level of detail and difficulty that is comfortable and meaningful. The intent is tomore » make physics relevant, intellectually accessible and fun. On-screen presenters and demonstrators will be females and males of various ages, ethnicities and backgrounds, and will include celebrities and physicists of note. A lean, layered design encourages repeated, cumulative study and makes the material useful for self-directed Teaming even by college students. THE REAL STUFF introduces a new science teaching paradigm, a way to teach science that will engage even students who have declined'' to be interested in science in the past. Increased participation in science by women, African-Americans and Spanish-speaking students is a particular goal.« less

Speaking across Levels--Generating and Addressing Levels Confusion in Discourse

ERIC Educational Resources Information Center

Stieff, Mike; Ryu, Minjung; Yip, Jason C.

2013-01-01

Reasoning across descriptive levels is a fundamental component of scientific reasoning, particularly in chemistry. Repeatedly, students are seen to confuse features applicable to one level across multiple levels despite instruction. Although many instances of such "levels confusion" have been documented, little is known about the…

Lessons that Bear Repeating and Repeating that Bears Lessons: An Interdisciplinary Unit on Principles of Minimalism in Modern Music, Art, and Poetry (Grades 4-8)

ERIC Educational Resources Information Center

Smigel, Eric; McDonald, Nan L.

2012-01-01

This theory-to-practice article focuses on interdisciplinary classroom activities based on principles of minimalism in modern music, art, and poetry. A lesson sequence was designed for an inner-city Grades 4 and 5 general classroom of English language learners, where the unit was taught, assessed, and documented by the authors. Included in the…

Tempered mlo broad-spectrum resistance to barley powdery mildew in an Ethiopian landrace

PubMed Central

Ge, Xintian; Deng, Weiwei; Lee, Zheng Zhou; Lopez-Ruiz, Francisco J.; Schweizer, Patrick; Ellwood, Simon R.

2016-01-01

Recessive mutations in the Mlo gene confer broad spectrum resistance in barley (Hordeum vulgare) to powdery mildew (Blumeria graminis f. sp. hordei), a widespread and damaging disease. However, all alleles discovered to date also display deleterious pleiotropic effects, including the naturally occurring mlo-11 mutant which is widely deployed in Europe. Recessive resistance was discovered in Eth295, an Ethiopian landrace, which was developmentally controlled and quantitative without spontaneous cell wall appositions or extensive necrosis and loss of photosynthetic tissue. This resistance is determined by two copies of the mlo-11 repeat units, that occur upstream to the wild-type Mlo gene, compared to 11–12 in commonly grown cultivars and was designated mlo-11 (cnv2). mlo-11 repeat unit copy number-dependent DNA methylation corresponded with cytological and macroscopic phenotypic differences between copy number variants. Sequence data indicated mlo-11 (cnv2) formed via recombination between progenitor mlo-11 repeat units and the 3′ end of an adjacent stowaway MITE containing region. mlo-11 (cnv2) is the only example of a moderated mlo variant discovered to date and may have arisen by natural selection against the deleterious effects of the progenitor mlo-11 repeat unit configuration. PMID:27404990

Testing the Predictive Capability of the High-Fidelity Generalized Method of Cells Using an Efficient Reformulation

NASA Technical Reports Server (NTRS)

Arnold, Steven M. (Technical Monitor); Bansal, Yogesh; Pindera, Marek-Jerzy

2004-01-01

The High-Fidelity Generalized Method of Cells is a new micromechanics model for unidirectionally reinforced periodic multiphase materials that was developed to overcome the original model's shortcomings. The high-fidelity version predicts the local stress and strain fields with dramatically greater accuracy relative to the original model through the use of a better displacement field representation. Herein, we test the high-fidelity model's predictive capability in estimating the elastic moduli of periodic composites characterized by repeating unit cells obtained by rotation of an infinite square fiber array through an angle about the fiber axis. Such repeating unit cells may contain a few or many fibers, depending on the rotation angle. In order to analyze such multi-inclusion repeating unit cells efficiently, the high-fidelity micromechanics model's framework is reformulated using the local/global stiffness matrix approach. The excellent agreement with the corresponding results obtained from the standard transformation equations confirms the new model's predictive capability for periodic composites characterized by multi-inclusion repeating unit cells lacking planes of material symmetry. Comparison of the effective moduli and local stress fields with the corresponding results obtained from the original Generalized Method of Cells dramatically highlights the original model's shortcomings for certain classes of unidirectional composites.

Mechanical properties of regular porous biomaterials made from truncated cube repeating unit cells: Analytical solutions and computational models.

PubMed

Hedayati, R; Sadighi, M; Mohammadi-Aghdam, M; Zadpoor, A A

2016-03-01

Additive manufacturing (AM) has enabled fabrication of open-cell porous biomaterials based on repeating unit cells. The micro-architecture of the porous biomaterials and, thus, their physical properties could then be precisely controlled. Due to their many favorable properties, porous biomaterials manufactured using AM are considered as promising candidates for bone substitution as well as for several other applications in orthopedic surgery. The mechanical properties of such porous structures including static and fatigue properties are shown to be strongly dependent on the type of the repeating unit cell based on which the porous biomaterial is built. In this paper, we study the mechanical properties of porous biomaterials made from a relatively new unit cell, namely truncated cube. We present analytical solutions that relate the dimensions of the repeating unit cell to the elastic modulus, Poisson's ratio, yield stress, and buckling load of those porous structures. We also performed finite element modeling to predict the mechanical properties of the porous structures. The analytical solution and computational results were found to be in agreement with each other. The mechanical properties estimated using both the analytical and computational techniques were somewhat higher than the experimental data reported in one of our recent studies on selective laser melted Ti-6Al-4V porous biomaterials. In addition to porosity, the elastic modulus and Poisson's ratio of the porous structures were found to be strongly dependent on the ratio of the length of the inclined struts to that of the uninclined (i.e. vertical or horizontal) struts, α, in the truncated cube unit cell. The geometry of the truncated cube unit cell approaches the octahedral and cube unit cells when α respectively approaches zero and infinity. Consistent with those geometrical observations, the analytical solutions presented in this study approached those of the octahedral and cube unit cells when α approached respectively 0 and infinity. Copyright © 2015 Elsevier B.V. All rights reserved.

Parallel multiphase microflows: fundamental physics, stabilization methods and applications.

PubMed

Aota, Arata; Mawatari, Kazuma; Kitamori, Takehiko

2009-09-07

Parallel multiphase microflows, which can integrate unit operations in a microchip under continuous flow conditions, are discussed. Fundamental physics, stabilization methods and some applications are shown.

An Investigation of the Fundamental Characteristics in Quality Online Spanish Instruction

ERIC Educational Resources Information Center

Don, Margaret Rose

2005-01-01

This article presents research findings investigating the fundamental characteristics in online Spanish instruction (at the university level in the United States) designed to maximize learning outcomes. The researcher collected data to develop a rubric of the fundamental characteristic in online Spanish instruction and then to determine whether…

A novel species-specific tandem repeat DNA family from Sinapis arvensis: detection of telomere-like sequences.

PubMed

Kapila, R; Das, S; Srivastava, P S; Lakshmikumaran, M

1996-08-01

DNA sequences representing a tandemly repeated DNA family of the Sinapis arvensis genome were cloned and characterized. The 700-bp tandem repeat family is represented by two clones, pSA35 and pSA52, which are 697 and 709 bp in length, respectively. Dot matrix analysis of the sequences indicates the presence of repeated elements within each monomeric unit. Sequence analysis of the repetitive region of clones pSA35 and pSA52 shows that there are several copies of a 7-bp repeat element organized in tandem. The consensus sequence of this repeat element is 5'-TTTAGGG-3'. These elements are highly mutated and the difference in length between the two clones is due to different copy numbers of these elements. The repetitive region of clone pSA35 has 26 copies of the element TTTAGGG, whereas clone pSA52 has 28 copies. The repetitive region in both clones is flanked on either side by inverted repeats that may be footprints of a transposition event. Sequence comparison indicates that the element TTTAGGG is identical to telomeric repeats present in Arabidopsis, maize, tomato, and other plants. However, Bal31 digestion kinetics indicates non-telomeric localization of the 700-bp tandem repeats. The clones represent a novel repeat family as (i) they contain telomere-like motifs as subrepeats within each unit; and (ii) they do not hybridize to related crucifers and are species-specific in nature.

Fundamental Fraction Knowledge of Preservice Elementary Teachers: A Cross-National Study in the United States and Taiwan

ERIC Educational Resources Information Center

Luo, Fenqjen; Lo, Jane-Jane; Leu, Yuh-Chyn

2011-01-01

The purpose of this paper is to show the similarities as well as the differences of fundamental fraction knowledge owned by preservice elementary teachers from the United States (N = 89) and Taiwan (N = 85). To this end, we examined and compared their performance on an instrument including 15 multiple-choice test items. The items were categorized…

[Readmission to an Adolescent Psychiatry Inpatient Unit: Readmission Rates and Risk Factors].

PubMed

Mendes, Patricia; Fonseca, Maria; Aguiar, Inês; Pangaio, Nuno; Confraria, Luísa; Queirós, Otília; Saraiva, Joana; Monteiro, Pedro; Guerra, João

2017-11-29

Most mental disorders have a chronic evolution and therefore a certain amount of psychiatric readmissions are inevitable. Several studies indicate that over 25% of child and adolescent inpatients were readmitted within one year of discharge. Several risk factors for psychiatric readmissions have been reported in the literature, but the history of repeated readmissions is the most consistent risk factor. Our aim is to calculate the readmission rates at 30 days and 12 months after discharge and to identify associated risk factors. The authors consulted the clinical files of patients admitted to the Inpatient Unit between 2010 and 2013, in order to calculate the readmission rates at 30 days and at 12 months. The demographic and clinical characteristics of the readmitted patients were analyzed and compared with a second group of patients with no hospital readmissions, in order to investigate possible predictors of readmission. A total of 445 patients were admitted to our inpatient unit between 2010 and 2013. Six adolescents were readmitted in a 30 days period (1.3%) and 52 were readmitted in a 12 month period after discharge (11.5%). Duration of the hospitalization and the previous number of mental health admissions were significant predictors of future hospital readmissions (p = 0.04 and p = 0.014). The low readmission rates may reflect the positive clinical and sociofamilial support being provided after discharge. Rehospitalisation is considered a fundamental target for intervention concerning prevention and intervention in mental healthcare. Thus, knowledge regarding their minimisation is crucial.

A Large-Scale, High-Resolution Hydrological Model Parameter Data Set for Climate Change Impact Assessment for the Conterminous US

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

Oubeidillah, Abdoul A; Kao, Shih-Chieh; Ashfaq, Moetasim

2014-01-01

To extend geographical coverage, refine spatial resolution, and improve modeling efficiency, a computation- and data-intensive effort was conducted to organize a comprehensive hydrologic dataset with post-calibrated model parameters for hydro-climate impact assessment. Several key inputs for hydrologic simulation including meteorologic forcings, soil, land class, vegetation, and elevation were collected from multiple best-available data sources and organized for 2107 hydrologic subbasins (8-digit hydrologic units, HUC8s) in the conterminous United States at refined 1/24 (~4 km) spatial resolution. Using high-performance computing for intensive model calibration, a high-resolution parameter dataset was prepared for the macro-scale Variable Infiltration Capacity (VIC) hydrologic model. The VICmore » simulation was driven by DAYMET daily meteorological forcing and was calibrated against USGS WaterWatch monthly runoff observations for each HUC8. The results showed that this new parameter dataset may help reasonably simulate runoff at most US HUC8 subbasins. Based on this exhaustive calibration effort, it is now possible to accurately estimate the resources required for further model improvement across the entire conterminous United States. We anticipate that through this hydrologic parameter dataset, the repeated effort of fundamental data processing can be lessened, so that research efforts can emphasize the more challenging task of assessing climate change impacts. The pre-organized model parameter dataset will be provided to interested parties to support further hydro-climate impact assessment.« less

Prevalence of Huntington's disease gene CAG trinucleotide repeat alleles in patients with bipolar disorder.

PubMed

Ramos, Eliana Marisa; Gillis, Tammy; Mysore, Jayalakshmi S; Lee, Jong-Min; Alonso, Isabel; Gusella, James F; Smoller, Jordan W; Sklar, Pamela; MacDonald, Marcy E; Perlis, Roy H

2015-06-01

Huntington's disease is a neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms that are caused by huntingtin gene (HTT) CAG trinucleotide repeat alleles of 36 or more units. A greater than expected prevalence of incompletely penetrant HTT CAG repeat alleles observed among individuals diagnosed with major depressive disorder raises the possibility that another mood disorder, bipolar disorder, could likewise be associated with Huntington's disease. We assessed the distribution of HTT CAG repeat alleles in a cohort of individuals with bipolar disorder. HTT CAG allele sizes from 2,229 Caucasian individuals diagnosed with DSM-IV bipolar disorder were compared to allele sizes in 1,828 control individuals from multiple cohorts. We found that HTT CAG repeat alleles > 35 units were observed in only one of 4,458 chromosomes from individuals with bipolar disorder, compared to three of 3,656 chromosomes from control subjects. These findings do not support an association between bipolar disorder and Huntington's disease. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The organization of repeating units in mitochondrial DNA from yeast petite mutants.

PubMed

Bos, J L; Heyting, C; Van der Horst, G; Borst, P

1980-04-01

We have reinvestigated the linkage orientation of repeating units in mtDNAs of yeast ρ(-) petite mutants containing an inverted duplication. All five petite mtDNAs studied contain a continuous segment of wild-type mtDNA, part of which is duplicated and present in inverted form in the repeat. We show by restriction enzyme analysis that the non-duplicated segments between the inverted duplications are present in random orientation in all five petite mtDNAs. There is no segregation of sub-types with unique orientation. We attribute this to the high rate of intramolecular recombination between the inverted duplications. The results provide additional evidence for the high rate of recombination of yeast mtDNA even in haploid ρ(-) petite cells.We conclude that only two types of stable sequence organization exist in petite mtDNA: petites without an inverted duplication have repeats linked in straight head-to-tail arrangement (abcabc); petites with an inverted duplication have repeats in which the non-duplicated segments are present in random orientation.

Investigation of the use of resilient modulus for Louisiana soils in the design of pavements: final report.

DOT National Transportation Integrated Search

1994-06-01

The 1986 AASHTO Guide for the Design of Pavement Structures has adopted the use of resilient modulus (M,) as a fundamental proponent to characterize flexible pavement materials. The resilient modulus is defmed as the ratio of the repeated axial devia...

Amygdala Habituation and Prefrontal Functional Connectivity in Youth with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Swartz, Johnna R.; Wiggins, Jillian Lee; Carrasco, Melissa; Lord, Catherine; Monk, Christopher S.

2013-01-01

Objective: Amygdala habituation, the rapid decrease in amygdala responsiveness to the repeated presentation of stimuli, is fundamental to the nervous system. Habituation is important for maintaining adaptive levels of arousal to predictable social stimuli and decreased habituation is associated with heightened anxiety. Input from the ventromedial…

Incremental Dynamic Analysis of Koyna Dam under Repeated Ground Motions

NASA Astrophysics Data System (ADS)

Zainab Nik Azizan, Nik; Majid, Taksiah A.; Nazri, Fadzli Mohamed; Maity, Damodar; Abdullah, Junaidah

2018-03-01

This paper discovers the incremental dynamic analysis (IDA) of concrete gravity dam under single and repeated earthquake loadings to identify the limit state of the dam. Seven ground motions with horizontal and vertical direction as seismic input considered in the nonlinear dynamic analysis based on the real repeated earthquake in the worldwide. All the ground motions convert to respond spectrum and scaled according to the developed elastic respond spectrum in order to match the characteristic of the ground motion to the soil type. The scaled was depends on the fundamental period, T1 of the dam. The Koyna dam has been selected as a case study for the purpose of the analysis by assuming that no sliding and rigid foundation, has been estimated. IDA curves for Koyna dam developed for single and repeated ground motions and the performance level of the dam identifies. The IDA curve of repeated ground motion shown stiffer rather than single ground motion. The ultimate state displacement for a single event is 45.59mm and decreased to 39.33mm under repeated events which are decreased about 14%. This showed that the performance level of the dam based on seismic loadings depend on ground motion pattern.

Structural study of the exopolysaccharide produced by a clinical isolate of Burkholderia cepacia.

PubMed

Cescutti, P; Bosco, M; Picotti, F; Impallomeni, G; Leitão, J H; Richau, J A; Sá-Correia, I

2000-07-14

The primary structure of the exopolysaccharide produced by a clinical isolate of the bacterium Burkholderia cepacia was studied by means of methylation analysis, selective degradation, NMR spectroscopy, and electrospray mass spectrometry. The resulting data showed that the parent repeating unit of the exopolysaccharide is a highly branched heptasaccharide with the following structure: Two acetyl groups are present per repeating unit, as noncarbohydrate substituents. Copyright 2000 Academic Press.

Intratypic variability of a tandem repeat locus within the DNA polymerase gene of human herpes simplex virus type 2.

PubMed

Sun, Yongjiang; Chan, Roy Kum Wah; Tan, Suat Hoon

2004-01-01

In this study, the irntratypic variability of a tandem repeat locus within the DNA polymerase (pol) gene of human herpes simplex virus type 2 (HSV2) was uncovered. The locus contained variable numbers of tandem dodecanucleotide (5'-GAC GAG GAC GGG-3') repetitive units. Our result showed that approximately 95% of analyzed HSV2 clinical isolates and the current GenBank HSV2 strains contained two copies of the repetitive units. From genital herpes specimens, three new HSV2 strains, which respectively contained 1, 3, and 4 copies of the repetitive units, were identified. This variable number of tandem repeat (VNTR) locus is absent in HSV1, and thus it also contributes to the intertypic variability of HSV1 and HSV2. The intratypic variability of the locus may be useful for HSV2 strain genotyping and this application is discussed.

The evolution and function of protein tandem repeats in plants.

PubMed

Schaper, Elke; Anisimova, Maria

2015-04-01

Sequence tandem repeats (TRs) are abundant in proteomes across all domains of life. For plants, little is known about their distribution or contribution to protein function. We exhaustively annotated TRs and studied the evolution of TR unit variations for all Ensembl plants. Using phylogenetic patterns of TR units, we detected conserved TRs with unit number and order preserved during evolution, and those TRs that have diverged via recent TR unit gains/losses. We correlated the mode of evolution of TRs to protein function. TR number was strongly correlated with proteome size, with about one-half of all TRs recognized as common protein domains. The majority of TRs have been highly conserved over long evolutionary distances, some since the separation of red algae and green plants c. 1.6 billion yr ago. Conversely, recurrent recent TR unit mutations were rare. Our results suggest that the first TRs by far predate the first plants, and that TR appearance is an ongoing process with similar rates across the plant kingdom. Interestingly, the few detected highly mutable TRs might provide a source of variation for rapid adaptation. In particular, such TRs are enriched in leucine-rich repeats (LRRs) commonly found in R genes, where TR unit gain/loss may facilitate resistance to emerging pathogens. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

A Cesium Rare-Earth Silicate Cs3 RESi6 O15 (RE=Dy-Lu, Y, In): The Parent of an Unusual Structural Class Featuring a Remarkable 57 Å Unit Cell Axis.

PubMed

Terry, Rylan; Vinton, Daniel; McMillen, Colin D; Kolis, Joseph W

2018-02-19

The structure of Cs 3 RESi 6 O 15 , where RE=Dy-Lu, Y, In, is unusual in that it contains octahedrally coordinated rare-earth ions; their relative orientation dictates the structure, as they rotate about the c-axis supported by the cyclic Si 6 O 15 framework. The repeat unit of the rotation is eight units generating a very long (ca. 57 Å) unit cell axis. This unusual repeat unit is created by the structural flexibility of the hexasilicate ring, which is in turn affected by the size of the rare earth ion as well as the size of alkali ion residing within the silicate layers. Previous work showed for the smaller Sc 3+ ion, the rotation of the octahedra is not sufficient to achieve closure at an integral repeat unit and an incommensurate structure results. The products are prepared as large, high quality single crystals using a high-temperature (650 °C) hydrothermal method with CsOH and F - mineralizers. The presence of fluoride is essential to the formation of the product. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

REACH. Electricity Units. Secondary.

ERIC Educational Resources Information Center

Smith, Gene; Sappe, Hoyt

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of electricity. The instructional units focus on electricity fundamentals and electric motors. Each unit follows a typical format that includes a unit sheet,…

Two tandemly repeated telomere-associated sequences in Nicotiana plumbaginifolia.

PubMed

Chen, C M; Wang, C T; Wang, C J; Ho, C H; Kao, Y Y; Chen, C C

1997-12-01

Two tandemly repeated telomere-associated sequences, NP3R and NP4R, have been isolated from Nicotiana plumbaginifolia. The length of a repeating unit for NP3R and NP4R is 165 and 180 nucleotides respectively. The abundance of NP3R, NP4R and telomeric repeats is, respectively, 8.4 x 10(4), 6 x 10(3) and 1.5 x 10(6) copies per haploid genome of N. plumbaginifolia. Fluorescence in situ hybridization revealed that NP3R is located at the ends and/or in interstitial regions of all 10 chromosomes and NP4R on the terminal regions of three chromosomes in the haploid genome of N. plumbaginifolia. Sequence homology search revealed that not only are NP3R and NP4R homologous to HRS60 and GRS, respectively, two tandem repeats isolated from N. tabacum, but that NP3R and NP4R are also related to each other, suggesting that they originated from a common ancestral sequence. The role of these repeated sequences in chromosome healing is discussed based on the observation that two to three copies of a telomere-similar sequence were present in each repeating unit of NP3R and NP4R.

Leishmania infantum: Lipophosphoglycan intraspecific variation and interaction with vertebrate and invertebrate hosts.

PubMed

Coelho-Finamore, J M; Freitas, V C; Assis, R R; Melo, M N; Novozhilova, N; Secundino, N F; Pimenta, P F; Turco, S J; Soares, R P

2011-03-01

Interspecies variations in lipophosphoglycan (LPG) have been the focus of intense study over the years due its role in specificity during sand fly-Leishmania interaction. This cell surface glycoconjugate is highly polymorphic among species with variations in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO(4) backbone of repeat units. However, the degree of intraspecies polymorphism in LPG of Leishmania infantum (syn. Leishmania chagasi) is not known. In this study, intraspecific variation in the repeat units of LPG was evaluated in 16 strains of L. infantum from Brazil, France, Algeria and Tunisia. The structural polymorphism in the L. infantum LPG repeat units was relatively slight and consisted of three types: type I does not have side chains; type II has one β-glucose residue that branches off the disaccharide-phosphate repeat units and type III has up to three glucose residues (oligo-glucosylated). The significance of these modifications was investigated during in vivo interaction of L. infantum with Lutzomyia longipalpis, and in vitro interaction of the parasites and respective LPGs with murine macrophages. There were no consequential differences in the parasite densities in sand fly midguts infected with Leishmania strains exhibiting type I, II and III LPGs. However, higher nitric oxide production was observed in macrophages exposed to glucosylated type II LPG. Copyright © 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Synthesis and study of the vibrational spectra of a first generation phosphorus-containing dendrimer with pyridyl functional groups

NASA Astrophysics Data System (ADS)

Furer, V. L.; Vandyukov, A. E.; Tripathi, V.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

2018-06-01

A new phosphorus-containing dendrimer of the first-generation with potential pharmacological activity was synthesized and studied by spectral methods. The FTIR, FT Raman, 1H and 31P NMR spectra of the first generation dendrimer G1 with a cyclotriphosphazene core, six branches sbnd Osbnd C6H4sbnd CHdbnd Nsbnd N(CH3)sbnd P(S) < and twelve 4-oxyphenethylamidopyridyl end groups sbnd Osbnd C6H4sbnd (CH2)2sbnd NHsbnd COsbnd C5NH4 were recorded. Amide groups of the dendrimer participate in the formation of an intermolecular hydrogen bond. Structure, geometric parameters, the frequency and intensity of the bands in the vibrational spectra were calculated using DFT with PBE functional and TZ2P basis set. Spectral characteristics, charge distribution and reactivity of the core, repeating units and terminal groups of the dendrimer were determined. The first-generation dendrimer molecule has the shape of a concave lens with a slightly non-planar cyclotriphosphazene core and flat repeating units. Repeating units are arranged symmetrically on three on each side of the core, there are no steric hindrances in it and the end groups are able to enter into subsequent reactions and dendrimer has a sufficiently large cavity for accommodating guest molecules. The HOMO covers the repeating units with a noticeable conjugation and the LUMO belongs to the terminal groups.

Ligand-Binding Properties and Conformational Dynamics of Autolysin Repeat Domains in Staphylococcal Cell Wall Recognition

PubMed Central

Zoll, Sebastian; Schlag, Martin; Shkumatov, Alexander V.; Rautenberg, Maren; Svergun, Dmitri I.; Götz, Friedrich

2012-01-01

The bifunctional major autolysin Atl plays a key role in staphylococcal cell separation. Processing of Atl yields catalytically active amidase (AM) and glucosaminidase (GL) domains that are each fused to repeating units. The two repeats of AM (R1 and R2) target the enzyme to the septum, where it cleaves murein between dividing cells. We have determined the crystal structure of R2, which reveals that each repeat folds into two half-open β-barrel subunits. We further demonstrate that lipoteichoic acid serves as a receptor for the repeats and that this interaction depends on conserved surfaces in each subunit. Small-angle X-ray scattering of the mature amidase reveals the presence of flexible linkers separating the AM, R1, and R2 units. Different levels of flexibility for each linker provide mechanistic insights into the conformational dynamics of the full-length protein and the roles of its components in cell wall association and catalysis. Our analysis supports a model in which the repeats direct the catalytic AM domain to the septum, where it can optimally perform the final step of cell division. PMID:22609916

Topological quantization in units of the fine structure constant.

PubMed

Maciejko, Joseph; Qi, Xiao-Liang; Drew, H Dennis; Zhang, Shou-Cheng

2010-10-15

Fundamental topological phenomena in condensed matter physics are associated with a quantized electromagnetic response in units of fundamental constants. Recently, it has been predicted theoretically that the time-reversal invariant topological insulator in three dimensions exhibits a topological magnetoelectric effect quantized in units of the fine structure constant α=e²/ℏc. In this Letter, we propose an optical experiment to directly measure this topological quantization phenomenon, independent of material details. Our proposal also provides a way to measure the half-quantized Hall conductances on the two surfaces of the topological insulator independently of each other.

Size Matters — Physiological Temperature Acclimation and Metabolic Scaling of Respiration for Eucalyptus Trees in a Warmer World

NASA Astrophysics Data System (ADS)

Drake, J. E.; Toelker, M. G.; Reich, P. B.

2016-12-01

Respiration drives the metabolism and growth of trees and represents a large and uncertain component of land surface feedbacks to climate change. A fixed scaling relationship between body mass and respiration has been described as a fundamental law across plants and animals, but this has been controversial. There is now ample evidence that trees adjust their respiration rates in response to temperature variation in their growth environment through physiological acclimation. Is acclimation sufficiently large to alter the scaling relationship between respiration and mass? Here, we make continuous measurements of in-situ­ respiration rates complemented with repeated measurements at a defined set temperature of 15°C for leaves and the entire aboveground component of Eucalyptus parramattensis and E. tereticornis trees growing in the field in warming experiments (ambient vs. +3°C) using 12 whole tree chambers in Australia. We report thousands of repeated measurements as trees grew from 1 to 9-m-tall, allowing a concurrent evaluation of physiological acclimation and metabolic scaling. Trees adjusted the respiration rates of leaves and whole-crowns in relation to the air temperature of the preceding three days, such that: (1) respiration rate per unit mass was reduced by warming when measured at a common temperature, and (2) in-situ whole-crown respiration rates per unit mass were equivalent across ambient and warmed trees (i.e., homeostatic respiration). Acclimation appeared to modify the scaling between respiration and mass, as the slope and intercept of this relationship were affected by recent air temperature. This suggests that metabolic scaling is not fixed, although the overall allometric scaling slope was consistent with the theoretical value of 0.75 (95% CI of 0.5 to 0.78). We suggest that considering acclimation and tree mass together provides new insight into a dynamic scaling of tree respiration, with implications for land surface feedbacks under climate warming.

TOPICAL REVIEW: Electric current activated/assisted sintering (ECAS): a review of patents 1906-2008

NASA Astrophysics Data System (ADS)

Grasso, Salvatore; Sakka, Yoshio; Maizza, Giovanni

2009-10-01

The electric current activated/assisted sintering (ECAS) is an ever growing class of versatile techniques for sintering particulate materials. Despite the tremendous advances over the last two decades in ECASed materials and products there is a lack of comprehensive reviews on ECAS apparatuses and methods. This paper fills the gap by tracing the progress of ECAS technology from 1906 to 2008 and surveys 642 ECAS patents published over more than a century. It is found that the ECAS technology was pioneered by Bloxam (1906 GB Patent No. 9020) who developed the first resistive sintering apparatus. The patents were searched by keywords or by cross-links and were withdrawn from the Japanese Patent Office (342 patents), the United States Patent and Trademark Office (175 patents), the Chinese State Intellectual Property Office of P.R.C. (69 patents) and the World Intellectual Property Organization (12 patents). A subset of 119 (out of 642) ECAS patents on methods and apparatuses was selected and described in detail with respect to their fundamental concepts, physical principles and importance in either present ECAS apparatuses or future ECAS technologies for enhancing efficiency, reliability, repeatability, controllability and productivity. The paper is divided into two parts, the first deals with the basic concepts, features and definitions of basic ECAS and the second analyzes the auxiliary devices/peripherals. The basic ECAS is classified with reference to discharge time (fast and ultrafast ECAS). The fundamental principles and definitions of ECAS are outlined in accordance with the scientific and patent literature.

Military Geodesy and Geospace Science Unit One

DTIC Science & Technology

1981-02-01

present section. The Coordinate Systems - The two fundamental planes for the definition of stellar and earth-fixed coordinate sys- tems are the...night are of equal length. The vernal eguinox .is taken as the fundamental direction (x-axis) for the space-fixed system . The plane of the equator is...GEOPHYSICS LABORATORY 4 AIR FORCE SYSTEMS COMMAND UNITED STATES AIR FORCE D HANSCOM AFB, MASSACHUSETTS 01731 81 9 10 038 BLANK PAGES IN THIS DOCUMENT WERE

The minisatellite of the GPI/AMF/NLK/MF gene: interspecies conservation and transcriptional activity.

PubMed

Williams, R R; Hassan-Walker, A F; Lavender, F L; Morgan, M; Faik, P; Ragoussis, J

2001-05-16

Minisatellites are tandemly repeated DNA sequences found throughout the genomes of all eukaryotes. They are regions often prone to instability and hence hypervariability; thus repeat unit sequence is generally not conserved beyond closely related species. We have studied the minisatellite located in intron 9 of the human glucose phosphate isomerase (GPI) gene (also known as neuroleukin, autocrine motility factor, maturation and differentiation factor) and have found, by Zoo blotting coupled with PCR amplification and DNA sequencing, that similar repeat units are present in seven other species of mammal. There is also evidence for the presence of the minisatellite in chicken. The repeat unit does not appear to be present at any other locus in these genomes. Minisatellite DNA has been reported to be involved in recombination activity, control of gene expression of nearby gene(s) (both transcriptional and translational), whilst others form protein coding regions. The high level of conservation exhibited by the GPI minisatellite, coupled with the unique location, strongly suggests a functional role. Our results from transient and stable transfections using luciferase reporter constructs have shown that the GPI minisatellite region can act to increase transcription from the SV40 promoter, CMV promoter and the human GPI promoter.

Fundamentals of Refrigeration.

ERIC Educational Resources Information Center

Sutliff, Ronald D.; And Others

This self-study course is designed to familiarize Marine enlisted personnel with the principles of the refrigeration process. The course contains five study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work units, each…

Protein folding and misfolding: mechanism and principles

PubMed Central

Englander, S. Walter; Mayne, Leland; Krishna, Mallela M. G.

2012-01-01

Two fundamentally different views of how proteins fold are now being debated. Do proteins fold through multiple unpredictable routes directed only by the energetically downhill nature of the folding landscape or do they fold through specific intermediates in a defined pathway that systematically puts predetermined pieces of the target native protein into place? It has now become possible to determine the structure of protein folding intermediates, evaluate their equilibrium and kinetic parameters, and establish their pathway relationships. Results obtained for many proteins have serendipitously revealed a new dimension of protein structure. Cooperative structural units of the native protein, called foldons, unfold and refold repeatedly even under native conditions. Much evidence obtained by hydrogen exchange and other methods now indicates that cooperative foldon units and not individual amino acids account for the unit steps in protein folding pathways. The formation of foldons and their ordered pathway assembly systematically puts native-like foldon building blocks into place, guided by a sequential stabilization mechanism in which prior native-like structure templates the formation of incoming foldons with complementary structure. Thus the same propensities and interactions that specify the final native state, encoded in the amino-acid sequence of every protein, determine the pathway for getting there. Experimental observations that have been interpreted differently, in terms of multiple independent pathways, appear to be due to chance misfolding errors that cause different population fractions to block at different pathway points, populate different pathway intermediates, and fold at different rates. This paper summarizes the experimental basis for these three determining principles and their consequences. Cooperative native-like foldon units and the sequential stabilization process together generate predetermined stepwise pathways. Optional misfolding errors are responsible for 3-state and heterogeneous kinetic folding. PMID:18405419

CRISPR and piRNAs: Fundamental Mechanisms and Key Applications of the Next Generation of Molecular Technologies in the Field of Toxicology

EPA Science Inventory

" Exploration into the roles of genes, the proteins that they encode, and the functions that they carry out within the cell is a founding pillar in the field of toxicology. Recent breakthroughs in clustered, regularly interspaced, short palindromic repeat (CRISPR) technology...

An evaluation of underwater epoxies to permanently install temperature sensors in mountain streams

Treesearch

Daniel J. Isaak; Dona L. Horan

2011-01-01

Stream temperature regimes are of fundamental importance in understanding the patterns and processes in aquatic ecosystems, and inexpensive digital sensors provide accurate and repeated measurements of temperature. Most temperature measurements in mountain streams are made only during summer months because of logistical constraints associated with stream access and...

Clamping characteristics study on different types of clamping unit

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

Jiao, Zhiwei; Liu, Haichao; Xie, Pengcheng

2015-05-22

Plastic products are becoming more and more widely used in aerospace, IT, digital electronics and many other fields. With the development of technology, the requirement of product precision is getting higher and higher. However, type and working performance of clamping unit play a decisive role in product precision. Clamping characteristics of different types of clamping unit are discussed in this article, which use finite element numerical analysis method through the software ABAQUS to study the clamping uniformity, and detect the clamping force repeatability precision. The result shows that compared with toggled three-platen clamping unit, clamping characteristics of internal circulation two-platenmore » clamping unit are better, for instance, its mold cavity deformation and force that bars and mold parting surface suffered are more uniform, and its clamping uniformity and repeatability precision is also better.« less

Wavelength shifting of intra-cavity photons: Adiabatic wavelength tuning in rapidly wavelength-swept lasers

PubMed Central

Jirauschek, Christian; Huber, Robert

2015-01-01

We analyze the physics behind the newest generation of rapidly wavelength tunable sources for optical coherence tomography (OCT), retaining a single longitudinal cavity mode during operation without repeated build up of lasing. In this context, we theoretically investigate the currently existing concepts of rapidly wavelength-swept lasers based on tuning of the cavity length or refractive index, leading to an altered optical path length inside the resonator. Specifically, we consider vertical-cavity surface-emitting lasers (VCSELs) with microelectromechanical system (MEMS) mirrors as well as Fourier domain mode-locked (FDML) and Vernier-tuned distributed Bragg reflector (VT-DBR) lasers. Based on heuristic arguments and exact analytical solutions of Maxwell’s equations for a fundamental laser resonator model, we show that adiabatic wavelength tuning is achieved, i.e., hopping between cavity modes associated with a repeated build up of lasing is avoided, and the photon number is conserved. As a consequence, no fundamental limit exists for the wavelength tuning speed, in principle enabling wide-range wavelength sweeps at arbitrary tuning speeds with narrow instantaneous linewidth. PMID:26203373

Fast Entanglement Establishment via Local Dynamics for Quantum Repeater Networks

NASA Astrophysics Data System (ADS)

Gyongyosi, Laszlo; Imre, Sandor

Quantum entanglement is a necessity for future quantum communication networks, quantum internet, and long-distance quantum key distribution. The current approaches of entanglement distribution require high-delay entanglement transmission, entanglement swapping to extend the range of entanglement, high-cost entanglement purification, and long-lived quantum memories. We introduce a fundamental protocol for establishing entanglement in quantum communication networks. The proposed scheme does not require entanglement transmission between the nodes, high-cost entanglement swapping, entanglement purification, or long-lived quantum memories. The protocol reliably establishes a maximally entangled system between the remote nodes via dynamics generated by local Hamiltonians. The method eliminates the main drawbacks of current schemes allowing fast entanglement establishment with a minimized delay. Our solution provides a fundamental method for future long-distance quantum key distribution, quantum repeater networks, quantum internet, and quantum-networking protocols. This work was partially supported by the GOP-1.1.1-11-2012-0092 project sponsored by the EU and European Structural Fund, by the Hungarian Scientific Research Fund - OTKA K-112125, and by the COST Action MP1006.

Space Medicine

NASA Technical Reports Server (NTRS)

Pool, Sam L.

2000-01-01

The National Academy of Sciences Committee on Space Biology and Medicine points out that space medicine is unique among space sciences, because in addition to addressing questions of fundamental scientific interest, it must address clinical or human health and safety issues as well. Efforts to identify how microgravity affects human physiology began in earnest by the United States in 1960 with the establishment of the National Aeronautics and Space Administration (NASA's) Life Sciences program. Before the first human space missions, prediction about the physiological effects of microgravity in space ranged from extremely severe to none at all. The understanding that has developed from our experiences in space to date allows us to be guardedly optimistic about the ultimate accommodations of humans to space flight. Only by our travels into the microgravity environment of space have we begun to unravel the mysteries associated with gravity's role in shaping human physiology. Space medicine is still at its very earliest stages. Development of this field has been slow for several reasons, including the limited number of space flights, the small number of research subjects, and the competition within the life sciences community and other disciplines for flight opportunities. The physiological changes incurred during space flight may have a dramatic effect on the course of an injury or illness. These physiological changes present an exciting challenge for the field of space medicine: how to best preserve human health and safety while simultaneously deciphering the effects of microgravity on human performance. As the United States considers the future of humans in long-term space travel, it is essential that the many mysteries as to how microgravity affects human systems be addressed with vigor. Based on the current state of our knowledge, the justification is excellent indeed compelling- for NASA to develop a sophisticated capability in space medicine. Teams of physicians and scientists should be actively engaged in fundamental and applied research designed to ensure that it is safe for humans to routinely and repeatedly stay and work in the microgravity environment of space.

Distribution and Evolution of Yersinia Leucine-Rich Repeat Proteins

PubMed Central

Hu, Yueming; Huang, He; Hui, Xinjie; Cheng, Xi; White, Aaron P.

2016-01-01

Leucine-rich repeat (LRR) proteins are widely distributed in bacteria, playing important roles in various protein-protein interaction processes. In Yersinia, the well-characterized type III secreted effector YopM also belongs to the LRR protein family and is encoded by virulence plasmids. However, little has been known about other LRR members encoded by Yersinia genomes or their evolution. In this study, the Yersinia LRR proteins were comprehensively screened, categorized, and compared. The LRR proteins encoded by chromosomes (LRR1 proteins) appeared to be more similar to each other and different from those encoded by plasmids (LRR2 proteins) with regard to repeat-unit length, amino acid composition profile, and gene expression regulation circuits. LRR1 proteins were also different from LRR2 proteins in that the LRR1 proteins contained an E3 ligase domain (NEL domain) in the C-terminal region or an NEL domain-encoding nucleotide relic in flanking genomic sequences. The LRR1 protein-encoding genes (LRR1 genes) varied dramatically and were categorized into 4 subgroups (a to d), with the LRR1a to -c genes evolving from the same ancestor and LRR1d genes evolving from another ancestor. The consensus and ancestor repeat-unit sequences were inferred for different LRR1 protein subgroups by use of a maximum parsimony modeling strategy. Structural modeling disclosed very similar repeat-unit structures between LRR1 and LRR2 proteins despite the different unit lengths and amino acid compositions. Structural constraints may serve as the driving force to explain the observed mutations in the LRR regions. This study suggests that there may be functional variation and lays the foundation for future experiments investigating the functions of the chromosomally encoded LRR proteins of Yersinia. PMID:27217422

A Legionella pneumophila collagen-like protein encoded by a gene with a variable number of tandem repeats is involved in the adherence and invasion of host cells.

PubMed

Vandersmissen, Liesbeth; De Buck, Emmy; Saels, Veerle; Coil, David A; Anné, Jozef

2010-05-01

Legionella pneumophila is a Gram-negative, facultative intracellular pathogen and the causative agent of Legionnaires' disease, a severe pneumonia in humans. Analysis of the Legionella sequenced genomes revealed a gene with a variable number of tandem repeats (VNTRs), whose number varies between strains. We examined the strain distribution of this gene among a collection of 108 clinical, environmental and hot spring serotype I strains. Twelve variants were identified, but no correlation was observed between the number of repeat units and clinical and environmental strains. The encoded protein contains the C-terminal consensus motif of outer membrane proteins and has a large region of collagen-like repeats that is encoded by the VNTR region. We have therefore annotated this protein Lcl for Legionella collagen-like protein. Lcl was shown to contribute to the adherence and invasion of host cells and it was demonstrated that the number of repeat units present in lcl had an influence on these adhesion characteristics.

Continuous Removal of Coal-Gasification Residue

NASA Technical Reports Server (NTRS)

Collins, Earl R., Jr.; Suitor, J.; Dubis, D.

1986-01-01

Continuous-flow hopper processes solid residue from coal gasification, converting it from ashes, cinders, and clinkers to particles size of sand granules. Unit does not require repeated depressurization of lockhopper to admit and release materials. Therefore consumes less energy. Because unit has no airlock valves opened and closed repeatedly on hot, abrasive particles, subjected to lesser wear. Coal-gasification residue flows slowly through pressure-letdown device. Material enters and leaves continuously. Cleanout door on each pressure-letdown chamber allows access for maintenance and emergencies.

REACH. Refrigeration Units.

ERIC Educational Resources Information Center

Snow, Rufus; And Others

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of refrigeration. The instructional units focus on refrigeration fundamentals, tubing and pipe, refrigerants, troubleshooting, window air conditioning, and…

Structure of chromatin and the linking number of DNA.

PubMed Central

Worcel, A; Strogatz, S; Riley, D

1981-01-01

Recent observations suggest that the basic supranucleosomal structure of chromatin is a zigzag helical ribbon with a repeat unit made of two nucleosomes connected by a relaxed spacer DNA. A remarkable feature of one particular ribbon is that it solves the apparent paradox between the number of DNA turns per nucleosome and the total linking number of a nucleosome-containing closed circular DNA molecule. We show here that the repeat unit of the proposed structure, which contains two nucleosomes with -1 3/4 DNA turns per nucleosome and one spacer crossover per repeat, contributes -2 to the linking number of closed circular DNA. Space-filling models show that the cylindrical 250-A chromatin fiber can be generated by twisting the ribbon. Images PMID:6940168

Identification and characterization of tandem repeats in exon III of dopamine receptor D4 (DRD4) genes from different mammalian species.

PubMed

Larsen, Svend Arild; Mogensen, Line; Dietz, Rune; Baagøe, Hans Jørgen; Andersen, Mogens; Werge, Thomas; Rasmussen, Henrik Berg

2005-12-01

In this study we have identified and characterized dopamine receptor D4 (DRD4) exon III tandem repeats in 33 public available nucleotide sequences from different mammalian species. We found that the tandem repeat in canids could be described in a novel and simple way, namely, as a structure composed of 15- and 12- bp modules. Tandem repeats composed of 18-bp modules were found in sequences from the horse, zebra, onager, and donkey, Asiatic bear, polar bear, common raccoon, dolphin, harbor porpoise, and domestic cat. Several of these sequences have been analyzed previously without a tandem repeat being found. In the domestic cow and gray seal we identified tandem repeats composed of 36-bp modules, each consisting of two closely related 18-bp basic units. A tandem repeat consisting of 9-bp modules was identified in sequences from mink and ferret. In the European otter we detected an 18-bp tandem repeat, while a tandem repeat consisting of 27-bp modules was identified in a sequence from European badger. Both these tandem repeats were composed of 9-bp basic units, which were closely related with the 9-bp repeat modules identified in the mink and ferret. Tandem repeats could not be identified in sequences from rodents. All tandem repeats possessed a high GC content with a strong bias for C. On phylogenetic analysis of the tandem repeats evolutionary related species were clustered into the same groups. The degree of conservation of the tandem repeats varied significantly between species. The deduced amino acid sequences of most of the tandem repeats exhibited a high propensity for disorder. This was also the case with an amino acid sequence of the human DRD4 exon III tandem repeat, which was included in the study for comparative purposes. We identified proline-containing motifs for SH3 and WW domain binding proteins, potential phosphorylation sites, PDZ domain binding motifs, and FHA domain binding motifs in the amino acid sequences of the tandem repeats. The numbers of potential functional sites varied pronouncedly between species. Our observations provide a platform for future studies of the architecture and evolution of the DRD4 exon III tandem repeat, and they suggest that differences in the structure of this tandem repeat contribute to specialization and generation of diversity in receptor function.

Hollow cathode heater development for the Space Station plasma contactor

NASA Technical Reports Server (NTRS)

Soulas, George C.

1993-01-01

A hollow cathode-based plasma contactor has been selected for use on the Space Station. During the operation of the plasma contactor, the hollow cathode heater will endure approximately 12000 thermal cycles. Since a hollow cathode heater failure would result in a plasma contactor failure, a hollow cathode heater development program was established to produce a reliable heater design. The development program includes the heater design, process documents for both heater fabrication and assembly, and heater testing. The heater design was a modification of a sheathed ion thruster cathode heater. Three heaters have been tested to date using direct current power supplies. Performance testing was conducted to determine input current and power requirements for achieving activation and ignition temperatures, single unit operational repeatability, and unit-to-unit operational repeatability. Comparisons of performance testing data at the ignition input current level for the three heaters show the unit-to-unit repeatability of input power and tube temperature near the cathode tip to be within 3.5 W and 44 degrees C, respectively. Cyclic testing was then conducted to evaluate reliability under thermal cycling. The first heater, although damaged during assembly, completed 5985 ignition cycles before failing. Two additional heaters were subsequently fabricated and have completed 3178 cycles to date in an on-going test.

An integration of integrated information theory with fundamental physics

PubMed Central

Barrett, Adam B.

2014-01-01

To truly eliminate Cartesian ghosts from the science of consciousness, we must describe consciousness as an aspect of the physical. Integrated Information Theory states that consciousness arises from intrinsic information generated by dynamical systems; however existing formulations of this theory are not applicable to standard models of fundamental physical entities. Modern physics has shown that fields are fundamental entities, and in particular that the electromagnetic field is fundamental. Here I hypothesize that consciousness arises from information intrinsic to fundamental fields. This hypothesis unites fundamental physics with what we know empirically about the neuroscience underlying consciousness, and it bypasses the need to consider quantum effects. PMID:24550877

Marine Electrician--Fundamentals.

ERIC Educational Resources Information Center

Sutliff, Ronald D.; And Others

This self-study course is designed to familiarize Marine Corps enlisted personnel with the principles of electricity, safety, and tools. The course contains three study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work units,…

O-Acetyl location on cepacian, the principal exopolysaccharide of Burkholderia cepacia complex bacteria.

PubMed

Cescutti, Paola; Impallomeni, Giuseppe; Garozzo, Domenico; Rizzo, Roberto

2011-12-27

Cepacian is an exopolysaccharide produced by the majority of the isolates belonging to the Burkholderia cepacia complex bacteria, a group of 17 species, some of which infect cystic fibrosis patients, sometime with fatal outcome. The repeating unit of cepacian consists of a backbone having a trisaccharidic repeating unit with three side chains, as reported in the formula below. The exopolysaccharide is also acetylated, carrying from one to three acetyl esters per repeating unit, depending on the strain examined. The consequences of O-acetyl substitution in a polysaccharide are important both for its biological functions and for industrial applications, including the preparation of conjugated vaccines, since O-acetyl groups are important immunogenic determinants. The location of acetyl groups was achieved by NMR spectroscopy and ESI mass spectrometry and revealed that these substituents are scattered in non-stoichiometric ratio on many sugar residues in different positions, a feature which adds to the already unique carbohydrate structure of the polysaccharide. Copyright © 2011 Elsevier Ltd. All rights reserved.

REACH. Air Conditioning Units.

ERIC Educational Resources Information Center

Garrison, Joe; And Others

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

Base units of the SI, fundamental constants and modern quantum physics.

PubMed

Bordé, Christian J

2005-09-15

Over the past 40 years, a number of discoveries in quantum physics have completely transformed our vision of fundamental metrology. This revolution starts with the frequency stabilization of lasers using saturation spectroscopy and the redefinition of the metre by fixing the velocity of light c. Today, the trend is to redefine all SI base units from fundamental constants and we discuss strategies to achieve this goal. We first consider a kinematical frame, in which fundamental constants with a dimension, such as the speed of light c, the Planck constant h, the Boltzmann constant k(B) or the electron mass m(e) can be used to connect and redefine base units. The various interaction forces of nature are then introduced in a dynamical frame, where they are completely characterized by dimensionless coupling constants such as the fine structure constant alpha or its gravitational analogue alpha(G). This point is discussed by rewriting the Maxwell and Dirac equations with new force fields and these coupling constants. We describe and stress the importance of various quantum effects leading to the advent of this new quantum metrology. In the second part of the paper, we present the status of the seven base units and the prospects of their possible redefinitions from fundamental constants in an experimental perspective. The two parts can be read independently and they point to these same conclusions concerning the redefinitions of base units. The concept of rest mass is directly related to the Compton frequency of a body, which is precisely what is measured by the watt balance. The conversion factor between mass and frequency is the Planck constant, which could therefore be fixed in a realistic and consistent new definition of the kilogram based on its Compton frequency. We discuss also how the Boltzmann constant could be better determined and fixed to replace the present definition of the kelvin.

Homeschooling and Religious Fundamentalism

ERIC Educational Resources Information Center

Kunzman, Robert

2010-01-01

This article considers the relationship between homeschooling and religious fundamentalism by focusing on their intersection in the philosophies and practices of conservative Christian homeschoolers in the United States. Homeschooling provides an ideal educational setting to support several core fundamentalist principles: resistance to…

Duration of the speech disfluencies of beginning stutterers.

PubMed

Zebrowski, P M

1991-06-01

This study compared the duration of within-word disfluencies and the number of repeated units per instance of sound/syllable and whole-word repetitions of beginning stutterers to those produced by age- and sex-matched nonstuttering children. Subjects were 10 stuttering children [9 males and 1 female; mean age 4:1 (years:months); age range 3:2-5:1), and 10 nonstuttering children (9 males and 1 female; mean age 4:0; age range: 2:10-5:1). Mothers of the stuttering children reported that their children had been stuttering for 1 year or less. One 300-word conversational speech sample from each of the stuttering and nonstuttering children was analyzed for (a) mean duration of sound/syllable repetition and sound prolongation, (b) mean number of repeated units per instance of sound/syllable and whole-word repetition, and (c) various related measures of the frequency of all between- and within-word speech disfluencies. There were no significant between-group differences for either the duration of acoustically measured sound/syllable repetitions and sound prolongations or the number of repeated units per instance of sound/syllable and whole-word repetition. Unlike frequency and type of speech disfluency produced, average duration of within-word disfluencies and number of repeated units per repetition do not differentiate the disfluent speech of beginning stutterers and their nonstuttering peers. Additional analyses support findings from previous perceptual work that type and frequency of speech disfluency, not duration, are the principal characteristics listeners use in distinguishing these two talker groups.

Structural elucidation of the O-antigen of the Shigella flexneri provisional serotype 88-893: structural and serological similarities with S. flexneri provisional serotype Y394 (1c).

PubMed

Foster, R A; Carlin, N I A; Majcher, M; Tabor, H; Ng, L-K; Widmalm, G

2011-05-01

The structure of the repeating unit of the O-antigen polysaccharide from Shigella flexneri provisional serotype 88-893 has been determined. (1)H and (13)C NMR spectroscopy as well as 2D NMR experiments were employed to elucidate the structure. The carbohydrate part of the hexasaccharide repeating unit is identical to the previously elucidated structure of the O-polysaccharide from S. flexneri prov. serotype Y394. The O-antigen of S. flexneri prov. serotype 88-893 carries 0.7 mol O-acetyl group per repeating unit located at O-2 of the 3-substituted rhamnosyl residue, as identified by H2BC and BS-CT-HMBC NMR experiments. The O-antigen polysaccharide is composed of hexasaccharide repeating units with the following structure: →2)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-Rhap2Ac-(1→3)[α-D-Glcp-(1→2)-α-D-Glcp-(1→4)]-β-D-GlcpNAc-(1→. Serological studies showed that type antigens for the two provisional serotypes are identical; in addition 88-893 expresses S. flexneri group factor 6 antigen. We propose that provisional serotypes Y394 and 88-893 be designated as two new serotypes 7a and 7b, respectively, in the S. flexneri typing scheme. Copyright © 2011 Elsevier Ltd. All rights reserved.

Pharmacological enhancement of calcium-activated potassium channel function reduces the effects of repeated stress on fear memory

PubMed Central

Atchley, Derek; Hankosky, Emily R.; Gasparotto, Kaylyn; Rosenkranz, J. Amiel

2012-01-01

Repeated stress impacts emotion, and can induce mood and anxiety disorders. These disorders are characterized by imbalance of emotional responses. The amygdala is fundamental in expression of emotion, and is hyperactive in many patients with mood or anxiety disorders. Stress also leads to hyperactivity of the amygdala in humans. In rodent studies, repeated stress causes hyperactivity of the amygdala, and increases fear conditioning behavior that is mediated by the basolateral amygdala (BLA). Calcium-activated potassium (KCa) channels regulate BLA neuronal activity, and evidence suggests reduced small conductance KCa (SK) channel function in male rats exposed to repeated stress. Pharmacological enhancement of SK channels reverses the BLA neuronal hyperexcitability caused by repeated stress. However, it is not known if pharmacological targeting of SK channels can repair the effects of repeated stress on amygdala-dependent behaviors. The purpose of this study was to test whether enhancement of SK channel function reverses the effects of repeated restraint on BLA-dependent auditory fear conditioning. We found that repeated restraint stress increased the expression of cued conditioned fear in male rats. However, 1-EBIO (1 or 10 mg/kg) or CyPPA (5 mg/kg) administered 30 minutes prior to testing of fear expression brought conditioned freezing to control levels, with little impact on fear expression in control handled rats. These results demonstrate that enhancement of SK channel function can reduce the abnormalities of BLA-dependent fear memory caused by repeated stress. Furthermore, this indicates that pharmacological targeting of SK channels may provide a novel target for alleviation of psychiatric symptoms associated with amygdala hyperactivity. PMID:22487247

CENPT bridges adjacent CENPA nucleosomes on young human α-satellite dimers

PubMed Central

Thakur, Jitendra; Henikoff, Steven

2016-01-01

Nucleosomes containing the CenH3 (CENPA or CENP-A) histone variant replace H3 nucleosomes at centromeres to provide a foundation for kinetochore assembly. CENPA nucleosomes are part of the constitutive centromere associated network (CCAN) that forms the inner kinetochore on which outer kinetochore proteins assemble. Two components of the CCAN, CENPC and the histone-fold protein CENPT, provide independent connections from the ∼171-bp centromeric α-satellite repeat units to the outer kinetochore. However, the spatial relationship between CENPA nucleosomes and these two branches remains unclear. To address this issue, we use a base-pair resolution genomic readout of protein–protein interactions, comparative chromatin immunoprecipitation (ChIP) with sequencing, together with sequential ChIP, to infer the in vivo molecular architecture of the human CCAN. In contrast to the currently accepted model in which CENPT associates with H3 nucleosomes, we find that CENPT is centered over the CENPB box between two well-positioned CENPA nucleosomes on the most abundant centromeric young α-satellite dimers and interacts with the CENPB/CENPC complex. Upon cross-linking, the entire CENPA/CENPB/CENPC/CENPT complex is nuclease-protected over an α-satellite dimer that comprises the fundamental unit of centromeric chromatin. We conclude that CENPA/CENPC and CENPT pathways for kinetochore assembly are physically integrated over young α-satellite dimers. PMID:27384170

Dual Ion Spectrometers and Their Calibration for the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

NASA Technical Reports Server (NTRS)

Coffey, V. N.; Chandler, M. O.

2017-01-01

The scientific target of NASA's Magnetospheric Multiscale (MMS) mission is to study the fundamentally important phenomenon of magnetic reconnection. Theoretical models of this process predict a small size, on the order of hundred kilometers, for the ion diffusion region where ions are demagnetized at the dayside magnetopause. This region may typically sweep over the spacecraft at relatively high speeds of 50 km/s, requiring the fast plasma investigation (FPI) instrument suite to have an extremely high time resolution for measurements of the 3D particle distribution functions. As part of the FPI on MMS, the 16 dual ion spectrometers (DIS) will provide fast (150 ms) 3D ion velocity distributions, from 10 to 30,000 eV/q, by combining the measurements from four dual spectrometers on each of four MMS spacecraft. For any multispacecraft mission, the response uniformity among the spectrometer set assumes an enhanced importance. Due to these demanding instrument requirements and the effort of calibrating more than 32 sensors (16 × 2) within a tight schedule, a highly systematic and precise calibration was required for measurement repeatability. To illustrate how this challenge was met, a brief overview of the FPI DIS was presented with a detailed discussion of the calibration method of approach and implementation. Finally, a discussion of DIS performance results, their unit-to-unit variation, and the lessons learned from this calibration effort are presented.

Optimization of sequence alignment for simple sequence repeat regions.

PubMed

Jighly, Abdulqader; Hamwieh, Aladdin; Ogbonnaya, Francis C

2011-07-20

Microsatellites, or simple sequence repeats (SSRs), are tandemly repeated DNA sequences, including tandem copies of specific sequences no longer than six bases, that are distributed in the genome. SSR has been used as a molecular marker because it is easy to detect and is used in a range of applications, including genetic diversity, genome mapping, and marker assisted selection. It is also very mutable because of slipping in the DNA polymerase during DNA replication. This unique mutation increases the insertion/deletion (INDELs) mutation frequency to a high ratio - more than other types of molecular markers such as single nucleotide polymorphism (SNPs).SNPs are more frequent than INDELs. Therefore, all designed algorithms for sequence alignment fit the vast majority of the genomic sequence without considering microsatellite regions, as unique sequences that require special consideration. The old algorithm is limited in its application because there are many overlaps between different repeat units which result in false evolutionary relationships. To overcome the limitation of the aligning algorithm when dealing with SSR loci, a new algorithm was developed using PERL script with a Tk graphical interface. This program is based on aligning sequences after determining the repeated units first, and the last SSR nucleotides positions. This results in a shifting process according to the inserted repeated unit type.When studying the phylogenic relations before and after applying the new algorithm, many differences in the trees were obtained by increasing the SSR length and complexity. However, less distance between different linage had been observed after applying the new algorithm. The new algorithm produces better estimates for aligning SSR loci because it reflects more reliable evolutionary relations between different linages. It reduces overlapping during SSR alignment, which results in a more realistic phylogenic relationship.

A novel tandem repeat sequence located on human chromosome 4p: isolation and characterization.

PubMed

Kogi, M; Fukushige, S; Lefevre, C; Hadano, S; Ikeda, J E

1997-06-01

In an effort to analyze the genomic region of the distal half of human chromosome 4p, to where Huntington disease and other diseases have been mapped, we have isolated the cosmid clone (CRS447) that was likely to contain a region with specific repeat sequences. Clone CRS447 was subjected to detailed analysis, including chromosome mapping, restriction mapping, and DNA sequencing. Chromosome mapping by both a human-CHO hybrid cell panel and FISH revealed that CRS447 was predominantly located in the 4p15.1-15.3 region. CRS447 was shown to consist of tandem repeats of 4.7-kb units present on chromosome 4p. A single EcoRI unit was subcloned (pRS447), and the complete sequence was determined as 4752 nucleotides. When pRS447 was used as a probe, the number of copies of this repeat per haploid genome was estimated to be 50-70. Sequence analysis revealed that it contained two internal CA repeats and one putative ORF. Database search established that this sequence was unreported. However, two homologous STS markers were found in the database. We concluded that CRS447/pRS447 is a novel tandem repeat sequence that is mainly specific to human chromosome 4p.

Unit Mastery Learning in an Introductory Geography Course

ERIC Educational Resources Information Center

Healy, John R.; Stephenson, Larry K.

1975-01-01

The unit mastery learning system is a method of individualized, self-paced learning which, through repeatable testing, enables students to attain a mastery of the content of one unit before proceeding to the next in the program. This article describes the unit mastery learning system and its application in an introductory geography course at Hilo…

Effects of Masking Noise on Laryngeal Resistance for Breathy, Normal, and Pressed Voice

ERIC Educational Resources Information Center

Grillo, Elizabeth U.; Abbott, Katherine Verdolini; Lee, Timothy D.

2010-01-01

Purpose: The purpose of the present study was to explore the effects of masking noise on laryngeal resistance for breathy, normal, and pressed voice in vocally trained women. Method: Eighteen vocally trained women produced breathy, normal, and pressed voice across 7 fundamental frequencies during a repeated CV utterance of /pi/ under normal and…

Fundamentally Speaking: A Focus on English as a Second Language (ESL).

ERIC Educational Resources Information Center

Winfield, Marie Yolette

The techniques used in teaching spoken and written English must be re-evaluated, and more effort should be directed toward helping individuals develop adequate ways of acquiring language skills. Classroom models that confront students with texts they cannot read effectively, and that compel them to repeat words and sentences in a chorus should be…

Carryover Effect of Joint Attention to Repeated Events in Chimpanzees and Young Children

ERIC Educational Resources Information Center

Okamoto-Barth, Sanae; Moore, Chris; Barth, Jochen; Subiaul, Francys; Povinelli, Daniel J.

2011-01-01

Gaze following is a fundamental component of triadic social interaction which includes events and an object shared with other individuals and is found in both human and nonhuman primates. Most previous work has focused only on the immediate reaction after following another's gaze. In contrast, this study investigated whether gaze following is…

Measuring the Effects of Instructional Environment and Student Engagement on Reading Achievement for Struggling Readers in Middle School

ERIC Educational Resources Information Center

Kennedy, Patrick Charles

2014-01-01

Teaching is a complex and fundamentally collaborative process, through which knowledge and skills are acquired as a result of repeated interactions between teachers and students. The effectiveness of these interactions depends on both the instructional environment created by the teacher and the extent to which students engage with that…

Visualizing the Fundamental Physics of Rapid Earth Penetration Using Transparent Soils

DTIC Science & Technology

2015-03-01

L R E P O R T DTRA-TR-14-80 Visualizing the Fundamental Physics of Rapid Earth Penetration Using Transparent Soils Approved for public... ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS...dose absorbed) roentgen shake slug torr (mm Hg, 0 C) *The bacquerel (Bq) is the SI unit of radioactivity ; 1 Bq = 1 event/s. **The Gray (GY) is

Sequence-sensitive exemplar and decision-bound accounts of speeded-classification performance in a modified Garner-tasks paradigm.

PubMed

Little, Daniel R; Wang, Tony; Nosofsky, Robert M

2016-09-01

Among the most fundamental results in the area of perceptual classification are the "correlated facilitation" and "filtering interference" effects observed in Garner's (1974) speeded categorization tasks: In the case of integral-dimension stimuli, relative to a control task, single-dimension classification is faster when there is correlated variation along a second dimension, but slower when there is orthogonal variation that cannot be filtered out (e.g., by attention). These fundamental effects may result from participants' use of a trial-by-trial bypass strategy in the control and correlated tasks: The observer changes the previous category response whenever the stimulus changes, and maintains responses if the stimulus repeats. Here we conduct modified versions of the Garner tasks that eliminate the availability of a pure bypass strategy. The fundamental facilitation and interference effects remain, but are still largely explainable in terms of pronounced sequential effects in all tasks. We develop sequence-sensitive versions of exemplar-retrieval and decision-bound models aimed at capturing the detailed, trial-by-trial response-time distribution data. The models combine assumptions involving: (i) strengthened perceptual/memory representations of stimuli that repeat across consecutive trials, and (ii) a bias to change category responses on trials in which the stimulus changes. These models can predict our observed effects and provide a more complete account of the underlying bases of performance in our modified Garner tasks. Copyright © 2016 Elsevier Inc. All rights reserved.

[We are a band: An anthropological vision of the medical community].

PubMed

Serrano Morón, P; Delgado Galán, M

2018-04-01

In this paper we try to explain, using an anthropological point of view, how the medical community behaves like a tribe like those who inhabit the Amazon forests or the African Savanna. The Family as fundamental unit of a band of hunter-gatherers also defines the Primary Care Centre and the professionals who work there, as an egalitarian group in which every member works for the good of the tribe. The leaders of the tribe, also called "Health Centre Managers", are also comparable to the "big men" of Polynesia or the aborigines, who leads hunting parties. Even the clashes between physicians about the responsibilities as regards patients have been described throughout history in the anthropological literature, and they repeat the patterns of the segmental groups. We finish by concluding that this vision of warring tribes has to be overcome in order to advance towards the improvement of our community's health. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

The development of manufactured flood risk: New Orleans' mid-century growth machine and the hurricane of 1947.

PubMed

Youngman, Nicole

2015-10-01

Much of the flood risk faced by coastal and riparian populations worldwide is manufactured rather than strictly natural--the outcome of human development projects involving municipal growth machines. This paper details the impacts of the hurricane of September 1947 on New Orleans, Louisiana, United States, and its relationship with the urban development and expansion efforts undertaken during and after the Second World War of 1939-45. New Orleans' newest drainage and shipping canals, which were a major part of its mid-twentieth century development initiative, funnelled the storm surge into the city, a pattern that would repeat itself in subsequent years. Unlike more infamous hurricanes, such as Betsy and Katrina of 1965 and 2005, respectively, the 1947 event is not well-known among disaster researchers. Yet, it provides a fundamental example of how local elites have continuously exacerbated flood risk throughout the city and surrounding area, leaving it simultaneously dependent on and endangered by its embedded system of drainage and shipping canals. © 2015 The Author(s). Disasters © Overseas Development Institute, 2015.

REACH. Electricity Units, Post-Secondary.

ERIC Educational Resources Information Center

Smith, Gene; And Others

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this postsecondary student manual contains individualized instructional units in the area of electricity. The instructional units focus on electricity fundamentals, electric motors, electrical components, and controls and installation.…

42 CFR 84.307 - Environmental treatments.

Code of Federal Regulations, 2013 CFR

2013-10-01

... environmental treatments simulating extreme storage temperatures, shock, and vibration. (b) The units will be...) The units will be subjected to vibration according to the following procedure: (1) The unit will be...; and (3) The vibration frequency regimen applied to each axis will be cyclical, repeating the sequence...

42 CFR 84.307 - Environmental treatments.

Code of Federal Regulations, 2012 CFR

2012-10-01

... environmental treatments simulating extreme storage temperatures, shock, and vibration. (b) The units will be...) The units will be subjected to vibration according to the following procedure: (1) The unit will be...; and (3) The vibration frequency regimen applied to each axis will be cyclical, repeating the sequence...

42 CFR 84.307 - Environmental treatments.

Code of Federal Regulations, 2014 CFR

2014-10-01

... environmental treatments simulating extreme storage temperatures, shock, and vibration. (b) The units will be...) The units will be subjected to vibration according to the following procedure: (1) The unit will be...; and (3) The vibration frequency regimen applied to each axis will be cyclical, repeating the sequence...

Slipped-strand mispairing at noncontiguous repeats in Poecilia reticulata: a model for minisatellite birth.

PubMed Central

Taylor, J S; Breden, F

2000-01-01

The standard slipped-strand mispairing (SSM) model for the formation of variable number tandem repeats (VNTRs) proposes that a few tandem repeats, produced by chance mutations, provide the "raw material" for VNTR expansion. However, this model is unlikely to explain the formation of VNTRs with long motifs (e.g., minisatellites), because the likelihood of a tandem repeat forming by chance decreases rapidly as the length of the repeat motif increases. Phylogenetic reconstruction of the birth of a mitochondrial (mt) DNA minisatellite in guppies suggests that VNTRs with long motifs can form as a consequence of SSM at noncontiguous repeats. VNTRs formed in this manner have motifs longer than the noncontiguous repeat originally formed by chance and are flanked by one unit of the original, noncontiguous repeat. SSM at noncontiguous repeats can therefore explain the birth of VNTRs with long motifs and the "imperfect" or "short direct" repeats frequently observed adjacent to both mtDNA and nuclear VNTRs. PMID:10880490

GFP-based fluorescence assay for CAG repeat instability in cultured human cells.

PubMed

Santillan, Beatriz A; Moye, Christopher; Mittelman, David; Wilson, John H

2014-01-01

Trinucleotide repeats can be highly unstable, mutating far more frequently than point mutations. Repeats typically mutate by addition or loss of units of the repeat. CAG repeat expansions in humans trigger neurological diseases that include myotonic dystrophy, Huntington disease, and several spinocerebellar ataxias. In human cells, diverse mechanisms promote CAG repeat instability, and in mice, the mechanisms of instability are varied and tissue-dependent. Dissection of mechanistic complexity and discovery of potential therapeutics necessitates quantitative and scalable screens for repeat mutation. We describe a GFP-based assay for screening modifiers of CAG repeat instability in human cells. The assay exploits an engineered intronic CAG repeat tract that interferes with expression of an inducible GFP minigene. Like the phenotypes of many trinucleotide repeat disorders, we find that GFP function is impaired by repeat expansion, in a length-dependent manner. The intensity of fluorescence varies inversely with repeat length, allowing estimates of repeat tract changes in live cells. We validate the assay using transcription through the repeat and engineered CAG-specific nucleases, which have previously been reported to induce CAG repeat instability. The assay is relatively fast and should be adaptable to large-scale screens of chemical and shRNA libraries.

GFP-Based Fluorescence Assay for CAG Repeat Instability in Cultured Human Cells

PubMed Central

Santillan, Beatriz A.; Moye, Christopher; Mittelman, David; Wilson, John H.

2014-01-01

Trinucleotide repeats can be highly unstable, mutating far more frequently than point mutations. Repeats typically mutate by addition or loss of units of the repeat. CAG repeat expansions in humans trigger neurological diseases that include myotonic dystrophy, Huntington disease, and several spinocerebellar ataxias. In human cells, diverse mechanisms promote CAG repeat instability, and in mice, the mechanisms of instability are varied and tissue-dependent. Dissection of mechanistic complexity and discovery of potential therapeutics necessitates quantitative and scalable screens for repeat mutation. We describe a GFP-based assay for screening modifiers of CAG repeat instability in human cells. The assay exploits an engineered intronic CAG repeat tract that interferes with expression of an inducible GFP minigene. Like the phenotypes of many trinucleotide repeat disorders, we find that GFP function is impaired by repeat expansion, in a length-dependent manner. The intensity of fluorescence varies inversely with repeat length, allowing estimates of repeat tract changes in live cells. We validate the assay using transcription through the repeat and engineered CAG-specific nucleases, which have previously been reported to induce CAG repeat instability. The assay is relatively fast and should be adaptable to large-scale screens of chemical and shRNA libraries. PMID:25423602

A prospective evaluation of the repeatability of left ventricular ejection fraction measurement by gated SPECT.

PubMed

Kliner, Dustin; Wang, Li; Winger, Daniel; Follansbee, William P; Soman, Prem

2015-12-01

Gated single-photon emission computed tomography (SPECT) is widely used for myocardial perfusion imaging and provides an automated assessment of left ventricular ejection fraction (LVEF). We prospectively tested the repeatability of serial SPECT-derived LVEF. This information is essential in order to inform the interpretation of a change in LV function on serial testing. Consenting patients (n = 50) from among those referred for clinically indicated gated myocardial perfusion SPECT (MPs) were recruited. Following the clinical rest-stress study, patients were repositioned on the camera table for a second acquisition using identical parameters. Patient positioning, image acquisition and processing for the second scan were independently performed by a technologist blinded to the clinical scan. Quantitative LVEF was generated by Quantitative Gated SPECT and recorded as EF1 and EF2, respectively. Repeatability of serial results was assessed using the Bland-Altman method. The limits of repeatability and repeatability coefficients were generated to determine the maximum variation in LVEF that can be expected to result from test variability. Repeatability was tested across a broad range of LV systolic function and myocardial perfusion. The mean difference between EF1 and EF2 was 1.6% (EF units), with 95% limits of repeatability of +9.1% to -6.0% (repeatability coefficient 7.5%). Correlation between serial EF measurements was excellent (r = 0.9809). Similar results were obtained in subgroups based on normal or abnormal EF and myocardial perfusion. The largest repeatability coefficient of 8.1% was seen in patients with abnormal LV systolic function. When test protocol and acquisition parameters are kept constant, a difference of >8% EF units on serial MPs is indicative of a true change 95% of the time.

Human minisatellite alleles detectable only after PCR amplification.

PubMed

Armour, J A; Crosier, M; Jeffreys, A J

1992-01-01

We present evidence that a proportion of alleles at two human minisatellite loci is undetected by standard Southern blot hybridization. In each case the missing allele(s) can be identified after PCR amplification and correspond to tandem arrays too short to detect by hybridization. At one locus, there is only one undetected allele (population frequency 0.3), which contains just three repeat units. At the second locus, there are at least five undetected alleles (total population frequency 0.9) containing 60-120 repeats; they are not detected because these tandem repeats give very poor signals when used as a probe in standard Southern blot hybridization, and also cross-hybridize with other sequences in the genome. Under these circumstances only signals from the longest tandemly repeated alleles are detectable above the nonspecific background. The structures of these loci have been compared in human and primate DNA, and at one locus the short human allele containing three repeat units is shown to be an intermediate state in the expansion of a monomeric precursor allele in primates to high copy number in the longer human arrays. We discuss the implications of such loci for studies of human populations, minisatellite isolation by cloning, and the evolution of highly variable tandem arrays.

Fundamentals of Welding. Teacher Edition.

ERIC Educational Resources Information Center

Fortney, Clarence; And Others

These instructional materials assist teachers in improving instruction on the fundamentals of welding. The following introductory information is included: use of this publication; competency profile; instructional/task analysis; related academic and workplace skills list; tools, materials, and equipment list; and 27 references. Seven units of…

Intravenous Fluid Therapy Course for the Licensed Practical Nurse. Instructor Guide.

ERIC Educational Resources Information Center

Missouri Univ., Columbia. Instructional Materials Lab.

This curriculum guide provides materials for a 10-unit intravenous (IV) therapy course for licensed practical nurses. Units contain from one to nine lessons. The first unit provides an introduction and orientation to the course. Subsequent units concern documentation, anatomy and physiology as applied to IV therapy, fundamental aspects of fluid…

Mountain Plains Learning Experience Guide: Automotive Repair. Course: Emission Systems.

ERIC Educational Resources Information Center

Schramm, C.; Osland, Walt

One of twelve individualized courses included in an automotive repair curriculum, this course covers the theory, testing, and servicing of automotive emission control systems. The course is comprised of one unit, Fundamentals of Emission Systems. The unit begins with a Unit Learning Experience Guide that gives directions for unit completion. The…

Cold Metalworking and Soldering. Unit A-4.

ERIC Educational Resources Information Center

Luft, Vernon D.; Backlund, Paul

This document is a teacher's guide for a unit in the college metalworking curriculum. It is intended to be used for four weeks of instruction for freshmen as an introductory course in metalworking. The unit is designed to give the student basic knowledge, fundamentals, and skills in metalworking. The unit's objectives are to develop in students…

Validity and repeatability of inertial measurement units for measuring gait parameters.

PubMed

Washabaugh, Edward P; Kalyanaraman, Tarun; Adamczyk, Peter G; Claflin, Edward S; Krishnan, Chandramouli

2017-06-01

Inertial measurement units (IMUs) are small wearable sensors that have tremendous potential to be applied to clinical gait analysis. They allow objective evaluation of gait and movement disorders outside the clinic and research laboratory, and permit evaluation on large numbers of steps. However, repeatability and validity data of these systems are sparse for gait metrics. The purpose of this study was to determine the validity and between-day repeatability of spatiotemporal metrics (gait speed, stance percent, swing percent, gait cycle time, stride length, cadence, and step duration) as measured with the APDM Opal IMUs and Mobility Lab system. We collected data on 39 healthy subjects. Subjects were tested over two days while walking on a standard treadmill, split-belt treadmill, or overground, with IMUs placed in two locations: both feet and both ankles. The spatiotemporal measurements taken with the IMU system were validated against data from an instrumented treadmill, or using standard clinical procedures. Repeatability and minimally detectable change (MDC) of the system was calculated between days. IMUs displayed high to moderate validity when measuring most of the gait metrics tested. Additionally, these measurements appear to be repeatable when used on the treadmill and overground. The foot configuration of the IMUs appeared to better measure gait parameters; however, both the foot and ankle configurations demonstrated good repeatability. In conclusion, the IMU system in this study appears to be both accurate and repeatable for measuring spatiotemporal gait parameters in healthy young adults. Copyright © 2017 Elsevier B.V. All rights reserved.

Fundamental Education: Common Ground for All Peoples. Report of a Special Committee to the Preparatory Commission of the United Nations Educational, Scientific and Cultural Organization.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France).

A landmark document, the out-of-print volume prepared for the first session of the UNESCO general conference, provides a preliminary outline of the proposed plan for fundamental education. Fundamental education is used to indicate a global field of activity that includes and goes beyond mass education, adult literacy, popular education, and…

Repeating ice-earthquakes beneath David Glacier from the 2012-2015 TAMNNET array

NASA Astrophysics Data System (ADS)

Walter, J. I.; Peng, Z.; Hansen, S. E.

2017-12-01

The continent of Antarctica has approximately the same surface area as the continental United States, though we know significantly less about its underlying geology and seismic activity. In recent years, improvements in seismic instrumentation, battery technology, and field deployment practices have allowed for continuous broadband stations throughout the dark Antarctic winter. We utilize broadband seismic data from a recent experiment (TAMNNET), which was originally proposed as a structural seismology experiment, for seismic event detection. Our target is to address fundamental questions about regional-scale crustal and environmental seismicity in the study region that comprises the Transantarctic Mountain area of Victoria and Oates Land. We identify most seismicity emanating from David Glacier, upstream of the Drygalski Ice Tongue, which has been documented by several other studies. In order to improve the catalog completeness for the David Glacier area, we utilize a matched-filter technique to identify potential missing earthquakes that may not have been originally detected. This technique utilizes existing cataloged waveforms as templates to scan through continuous data and to identify repeating or nearby earthquakes. With a more robust catalog, we evaluate relative changes in icequake positions, recurrence intervals, and other first-order information. In addition, we attempt to further refine locations of other regional seismicity using a variety of methods including body and surface wave polarization, beamforming, surface wave dispersion, and other seismological methods. This project highlights the usefulness of archiving raw datasets (i.e., passive seismic continuous data), so that researchers may apply new algorithms or techniques to test hypotheses not originally or specifically targeted by the original experimental design.

Entanglement-Gradient Routing for Quantum Networks.

PubMed

Gyongyosi, Laszlo; Imre, Sandor

2017-10-27

We define the entanglement-gradient routing scheme for quantum repeater networks. The routing framework fuses the fundamentals of swarm intelligence and quantum Shannon theory. Swarm intelligence provides nature-inspired solutions for problem solving. Motivated by models of social insect behavior, the routing is performed using parallel threads to determine the shortest path via the entanglement gradient coefficient, which describes the feasibility of the entangled links and paths of the network. The routing metrics are derived from the characteristics of entanglement transmission and relevant measures of entanglement distribution in quantum networks. The method allows a moderate complexity decentralized routing in quantum repeater networks. The results can be applied in experimental quantum networking, future quantum Internet, and long-distance quantum communications.

Is the learn unit a fundamental measure of pedagogy?

PubMed Central

Greer, R. Douglas; McDonough, Sally Hogin

1999-01-01

We propose a measure of teaching, the learn unit, that explicitly describes the interaction between teachers and their students. The theoretical, educational research, and applied behavior analysis literatures all converge on the learn unit as a fundamental measure of teaching. The theoretical literature proposes the construct of the interlocking operant and embraces verbal behavior, social interaction, and translations of psychological constructs into complex theoretical respondent-operant interactions and behavior-behavior relations. Research findings in education and applied behavior analysis on engaged academic time, opportunity to respond, active student responding, teacher-student responding, student-teacher responding, tutor-tutee responding, tutee-tutor responding, and verbal episodes between individuals all support a measure of interlocking responses. More recently, research analyzing the components of both the students' and teachers' behavior suggests that the learn unit is the strongest predictor of effective teaching. Finally, we propose applications of the learn unit to other issues in pedagogy not yet researched and the relation of learn units to the verbal behavior of students. PMID:22478317

Population genetics and new insight into range of CAG repeats of spinocerebellar ataxia type 3 in the Han Chinese population.

PubMed

Gan, Shi-Rui; Ni, Wang; Dong, Yi; Wang, Ning; Wu, Zhi-Ying

2015-01-01

Spinocerebellar ataxia type 3 (SCA3), also called Machado-Joseph disease (MJD), is one of the most common SCAs worldwide and caused by a CAG repeat expansion located in ATXN3 gene. Based on the CAG repeat numbers, alleles of ATXN3 can be divided into normal alleles (ANs), intermediate alleles (AIs) and expanded alleles (AEs). It was controversial whether the frequency of large normal alleles (large ANs) is related to the prevalence of SCA3 or not. And there were huge chaos in the comprehension of the specific numbers of the range of CAG repeats which is fundamental for genetic analysis of SCA3. To illustrate these issues, we made a novel CAG repeat ladder to detect CAG repeats of ATXN3 in 1003 unrelated Chinese normal individuals and studied haplotypes defined by three single nucleotide polymorphisms (SNPs) closed to ATXN3. We found that the number of CAG repeats ranged from 13 to 49, among them, 14 was the most common number. Positive skew, the highest frequency of large ANs and 4 AIs which had never been reported before were found. Also, AEs and large ANs shared the same haplotypes defined by the SNPs. Based on these data and other related studies, we presumed that de novo mutations of ATXN3 emerging from large ANs are at least one survival mechanisms of mutational ATXN3 and we can redefine the range of CAG repeats as: ANs≤44, 45 ≤AIs ≤49 and AEs≥50.

19 CFR 10.619 - Repeated false or unsupported preference claims.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Republic-Central America-United States Free Trade Agreement Origin Verifications and Determinations § 10... 19 Customs Duties 1 2010-04-01 2010-04-01 false Repeated false or unsupported preference claims. 10.619 Section 10.619 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND...

Exploring Reticence in Research Methods: The Experience of Studying Psychological Research Methods in Higher Education

ERIC Educational Resources Information Center

Kingsley, Barbara E.; Robertson, Julia M.

2017-01-01

As a fundamental element of any psychology degree, the teaching and learning of research methods is repeatedly brought into sharp focus, and it is often regarded as a real challenge by undergraduate students. The reasons for this are complex, but frequently attributed to an aversion of maths. To gain a more detailed understanding of students'…

Speculative behavior and asset price dynamics.

PubMed

Westerhoff, Frank

2003-07-01

This paper deals with speculative trading. Guided by empirical observations, a nonlinear deterministic asset pricing model is developed in which traders repeatedly choose between technical and fundamental analysis to determine their orders. The interaction between the trading rules produces complex dynamics. The model endogenously replicates the stylized facts of excess volatility, high trading volumes, shifts in the level of asset prices, and volatility clustering.

Lies, Damn Lies, and Statistics Revisited: A Comparison of Three Methods of Representing Change. AIR 1991 Annual Forum Paper.

ERIC Educational Resources Information Center

Pike, Gary R.

Because change is fundamental to education and the measurement of change assesses the quality and effectiveness of postsecondary education, this study examined three methods of measuring change: (1) gain scores; (2) residual scores; and (3) repeated measures. Data for the study was obtained from transcripts of 722 graduating seniors at the…

The Effect of Syllable Repetition Rate on Vocal Characteristics

ERIC Educational Resources Information Center

Topbas, Oya; Orlikoff, Robert F.; St. Louis, Kenneth O.

2012-01-01

This study examined whether mean vocal fundamental frequency ("F"[subscript 0]) or speech sound pressure level (SPL) varies with changes in syllable repetition rate. Twenty-four young adults (12 M and 12 F) repeated the syllables/p[inverted v]/,/p[inverted v]t[schwa]/, and/p[inverted v]t[schwa]k[schwa]/at a modeled "slow" rate of approximately one…

40 CFR 1066.20 - Units of measure and overview of calculations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Applicability and General Provisions § 1066.20 Units of..., repeatability, linearity, or noise specification. See 40 CFR 1065.1001 for the definition of tolerance. In this...

Handedness in shearing auxetics creates rigid and compliant structures

NASA Astrophysics Data System (ADS)

Lipton, Jeffrey Ian; MacCurdy, Robert; Manchester, Zachary; Chin, Lillian; Cellucci, Daniel; Rus, Daniela

2018-05-01

In nature, repeated base units produce handed structures that selectively bond to make rigid or compliant materials. Auxetic tilings are scale-independent frameworks made from repeated unit cells that expand under tension. We discovered how to produce handedness in auxetic unit cells that shear as they expand by changing the symmetries and alignments of auxetic tilings. Using the symmetry and alignment rules that we developed, we made handed shearing auxetics that tile planes, cylinders, and spheres. By compositing the handed shearing auxetics in a manner inspired by keratin and collagen, we produce both compliant structures that expand while twisting and deployable structures that can rigidly lock. This work opens up new possibilities in designing chemical frameworks, medical devices like stents, robotic systems, and deployable engineering structures.

Variable Number Of Tandem Repeats (VNTR) and its application in bacterial epidemiology.

PubMed

Ramazanzadeh, Rashid; McNerney, Ruth

2007-08-15

Molecular epidemiology is the using of molecular techniques to study bacterial distribution in human populations. Recently molecular epidemiologist benefit from several techniques such as Variable Number Tandem Repeat (VNTR) typing method to typing bacterial strains. Variable Number Tandem Repeat (VNTR) typing is a tool for genotyping and provides data in a simple and numeric format based on the number of repetitive sequences. VNTR for first time identified in M. tuberculosis as Mycobacterial Interspersed Repeat Units (MIRUs). General terms of VNTR have now been reported in Bacillus anthracis, Legionella pneumophila, Pseudomonas aeruginosa, Salmonella enterica and Escherichia coli O157.

Thymidylate synthase repeat polymorphisms and risk of neural tube defects in a population from the northern United Kingdom.

PubMed

Wilding, Craig S; Relton, Caroline L; Sutton, Matthew J; Jonas, Pat A; Lynch, Sally-Ann; Tawn, E Janet; Burn, John

2004-07-01

A 28-bp repeat polymorphism in the 5'UTR of the thymidylate synthase (TYMS) gene represents a candidate risk factor for neural tube defects (NTDs) due to involvement in folate-dependent homocysteine metabolism. Non-Hispanic, white, U.S. citizens carrying at least one 2x 28-bp repeat allele have recently been shown to be at a four-fold increased risk of spina bifida (SB). We investigated the association between this polymorphism and risk of NTD in families affected by NTDs and controls from the northern United Kingdom (UK). PCR was performed on genomic DNA extracted from blood or mouth swabs of family members affected by NTDs (mothers, fathers, and cases), and unaffected controls (mothers and infants) to determine the number of 28-bp repeat units within the promoter region of TYMS. Case-control and TDT analyses of the influence of TYMS genotype on risk of NTD, or NTD pregnancy, were conducted. Odds ratio (OR) analysis indicated that individuals carrying the 2x 28-bp repeat allele either in homozygous or heterozygous form, are not at increased risk of NTDs, or of having an NTD affected pregnancy. Control population allele frequencies are seen to be markedly different between the U.S. controls and those in this study. TYMS polymorphism appears to be not universally associated with NTD risk across Caucasian samples. The elevated risk of spina bifida in U.S. samples appears to be driven by an unusually low risk allele (2x 28 bp) frequency in control samples. Family based (TDT) testing of U.S. samples is therefore advocated.

Electric current activated/assisted sintering (ECAS): a review of patents 1906–2008

PubMed Central

Grasso, Salvatore; Sakka, Yoshio; Maizza, Giovanni

2009-01-01

The electric current activated/assisted sintering (ECAS) is an ever growing class of versatile techniques for sintering particulate materials. Despite the tremendous advances over the last two decades in ECASed materials and products there is a lack of comprehensive reviews on ECAS apparatuses and methods. This paper fills the gap by tracing the progress of ECAS technology from 1906 to 2008 and surveys 642 ECAS patents published over more than a century. It is found that the ECAS technology was pioneered by Bloxam (1906 GB Patent No. 9020) who developed the first resistive sintering apparatus. The patents were searched by keywords or by cross-links and were withdrawn from the Japanese Patent Office (342 patents), the United States Patent and Trademark Office (175 patents), the Chinese State Intellectual Property Office of P.R.C. (69 patents) and the World Intellectual Property Organization (12 patents). A subset of 119 (out of 642) ECAS patents on methods and apparatuses was selected and described in detail with respect to their fundamental concepts, physical principles and importance in either present ECAS apparatuses or future ECAS technologies for enhancing efficiency, reliability, repeatability, controllability and productivity. The paper is divided into two parts, the first deals with the basic concepts, features and definitions of basic ECAS and the second analyzes the auxiliary devices/peripherals. The basic ECAS is classified with reference to discharge time (fast and ultrafast ECAS). The fundamental principles and definitions of ECAS are outlined in accordance with the scientific and patent literature. PMID:27877308

Distribution and sequence homogeneity of an abundant satellite DNA in the beetle, Tenebrio molitor.

PubMed Central

Davis, C A; Wyatt, G R

1989-01-01

The mealworm beetle, Tenebrio molitor, contains an unusually abundant and homogeneous satellite DNA which constitutes up to 60% of its genome. The satellite DNA is shown to be present in all of the chromosomes by in situ hybridization. 18 dimers of the repeat unit were cloned and sequenced. The consensus sequence is 142 nt long and lacks any internal repeat structure. Monomers of the sequence are very similar, showing on average a 2% divergence from the calculated consensus. Variant nucleotides are scattered randomly throughout the sequence although some variants are more common than others. Neighboring repeat units are no more alike than randomly chosen ones. The results suggest that some mechanism, perhaps gene conversion, is acting to maintain the homogeneity of the satellite DNA despite its abundance and distribution on all of the chromosomes. Images PMID:2762148

Implementation of a Smeared Crack Band Model in a Micromechanics Framework

NASA Technical Reports Server (NTRS)

Pineda, Evan J.; Bednarcyk, Brett A.; Waas, Anthony M.; Arnold, Steven M.

2012-01-01

The smeared crack band theory is implemented within the generalized method of cells and high-fidelity generalized method of cells micromechanics models to capture progressive failure within the constituents of a composite material while retaining objectivity with respect to the size of the discretization elements used in the model. An repeating unit cell containing 13 randomly arranged fibers is modeled and subjected to a combination of transverse tension/compression and transverse shear loading. The implementation is verified against experimental data (where available), and an equivalent finite element model utilizing the same implementation of the crack band theory. To evaluate the performance of the crack band theory within a repeating unit cell that is more amenable to a multiscale implementation, a single fiber is modeled with generalized method of cells and high-fidelity generalized method of cells using a relatively coarse subcell mesh which is subjected to the same loading scenarios as the multiple fiber repeating unit cell. The generalized method of cells and high-fidelity generalized method of cells models are validated against a very refined finite element model.

Progressive Failure of a Unidirectional Fiber-Reinforced Composite Using the Method of Cells: Discretization Objective Computational Results

NASA Technical Reports Server (NTRS)

Pineda, Evan J.; Bednarcyk, Brett A.; Waas, Anthony M.; Arnold, Steven M.

2012-01-01

The smeared crack band theory is implemented within the generalized method of cells and high-fidelity generalized method of cells micromechanics models to capture progressive failure within the constituents of a composite material while retaining objectivity with respect to the size of the discretization elements used in the model. An repeating unit cell containing 13 randomly arranged fibers is modeled and subjected to a combination of transverse tension/compression and transverse shear loading. The implementation is verified against experimental data (where available), and an equivalent finite element model utilizing the same implementation of the crack band theory. To evaluate the performance of the crack band theory within a repeating unit cell that is more amenable to a multiscale implementation, a single fiber is modeled with generalized method of cells and high-fidelity generalized method of cells using a relatively coarse subcell mesh which is subjected to the same loading scenarios as the multiple fiber repeating unit cell. The generalized method of cells and high-fidelity generalized method of cells models are validated against a very refined finite element model.

Identification of a highly sulfated fucoidan from sea cucumber Pearsonothuria graeffei with well-repeated tetrasaccharides units.

PubMed

Hu, Yaqin; Li, Shan; Li, Junhui; Ye, Xingqian; Ding, Tian; Liu, Donghong; Chen, Jianchu; Ge, Zhiwei; Chen, Shiguo

2015-12-10

Sea cucumber fucoidan is a major bioactive component of sea cucumber. The structures of fucoidans have significant influences on their biological activities. The present study clarified the delicate structure of a fucoidan from Pearsonothuria graeffei. Fucoidan was obtained after papain digestion and purified by ion chromatography. The carbohydrate sequence of fucoidan was firstly determined by negative-ion electrospray tandem mass spectrometry (ES-MS) with collision-induced dissociation of the oligosaccharide fragments, which were obtained by mild acid hydrolysis, and completed by NMR for assignment of the anomeric conformation. It was unambiguously identified as a tetrasaccharide repeating unit with a backbone of [ → 3Fuc (2S, 4S) α1 → 3Fucα1→ 3Fuc (4S) α1 → 3Fuc#7 × 10#]n. The glycosidic bonds between the non-sulfated and 2,4-O-disulfated fucose residues were selectively cleaved, and highly ordered oligosaccharide fragments with a tetrasaccharide repeating unit were obtained. The highly 4-O- and 2, 4-di-O-sulfated polysaccharide deserves further developments for Pharmacia use. Copyright © 2015 Elsevier Ltd. All rights reserved.

The temporal characteristics of humpback whale songs

NASA Astrophysics Data System (ADS)

Au, Whitlow W. L.; Lammers, Marc O.; Stimpert, Alison; Schotten, Michiel

2005-09-01

Songs sung by male humpback whales consist of distinct, pulsed sounds that are designated as units. Units are produced in some sequence to form a phrase, a repeated set of phrases forms a theme, and repeated themes form a song. A song can last from minutes to hours. The songs of eight humpback whales were recorded with a vertical array of five hydrophones spaced 7 m apart with the array located within 100 m of the whales. At least seven distinct units were identified aurally from this data set obtained during the 2002 winter humpback whale session in Hawaii. Four distinct recurring themes were found in the songs, and for each whale at least two themes were recorded. The average duration of each unit sampled and the silent interval following the unit were determined in order to describe the temporal characteristics of the songs. From the data the temporal consistency and cadence control of unit production by each humpback whale and between whales were determined. Understanding the temporal and spectral characteristics of units within songs and how these units vary between whales could ultimately help in the design of computer algorithms to automatically identify individual whales.

Drafting Fundamentals. Drafting Module 1. Instructor's Guide.

ERIC Educational Resources Information Center

Missouri Univ., Columbia. Instructional Materials Lab.

This Missouri Vocational Instruction Management System instructor's drafting guide has been keyed to the drafting competency profile developed by state industry and education professionals. The guide contains a cross-reference table of instructional materials. Ten units cover drafting fundamentals: (1) introduction to drafting; (2) general safety;…

Motor control for a brushless DC motor

NASA Technical Reports Server (NTRS)

Peterson, William J. (Inventor); Faulkner, Dennis T. (Inventor)

1985-01-01

This invention relates to a motor control system for a brushless DC motor having an inverter responsively coupled to the motor control system and in power transmitting relationship to the motor. The motor control system includes a motor rotor speed detecting unit that provides a pulsed waveform signal proportional to rotor speed. This pulsed waveform signal is delivered to the inverter to thereby cause an inverter fundamental current waveform output to the motor to be switched at a rate proportional to said rotor speed. In addition, the fundamental current waveform is also pulse width modulated at a rate proportional to the rotor speed. A fundamental current waveform phase advance circuit is controllingly coupled to the inverter. The phase advance circuit is coupled to receive the pulsed waveform signal from the motor rotor speed detecting unit and phase advance the pulsed waveform signal as a predetermined function of motor speed to thereby cause the fundamental current waveform to be advanced and thereby compensate for fundamental current waveform lag due to motor winding reactance which allows the motor to operate at higher speeds than the motor is rated while providing optimal torque and therefore increased efficiency.

Complete structure of the cell surface polysaccharide of Streptococcus oralis C104: A 600-MHz NMR study

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

Abeygunawardana, C.; Bush, C.A.; Cisar, J.O.

1991-09-03

Specific lectin-carbohydrate interactions between certain oral streptococci and actinomyces contribute to the microbial colonization of teeth. The receptor molecules of Streptococcus oralis, 34, ATCC 10557, and Streptococcus mitis J22 for the galactose and N-acetylgalactosamine reactive fimbrial lectins of Actinomyces viscosus and Actinomyces naeslundii are antigenically distinct polysaccharides, each formed by a different phosphodiester-linked oligosaccharide repeating unit. Receptor polysaccharide was isolated form S. oralis C104 cells and was shown to contain galactose, N-acetylgalactosamine, ribitol, and phosphate with molar ratios of 4:1:1:1. The {sup 1}H NMR spectrum of the polysaccharide shows that it contains a repeating structure. The individual sugars in themore » repeating unit were identified by {sup 1}H coupling constants observed in E-COSY and DQF-COSY spectra. NMR methods included complete resonance assignments ({sup 1}H and {sup 13}C) by various homonuclear and heteronuclear correlation experiments that utilize scalar couplings. Sequence and linkage assignments were obtained from the heteronuclear multiple-bond correlation (HMBC) spectrum. This analysis shows that the receptor polysaccharide of S. oralis C104 is a ribitol teichoic acid polymer composed of a linear hexasaccharide repeating unit containing two residues each of galactopyranose and galactofuranose and a residue each of GalNAc and ribitol joined end to end by phosphodiester linkages.« less

A Dynamic Tandem Repeat in Monocotyledons Inferred from a Comparative Analysis of Chloroplast Genomes in Melanthiaceae.

PubMed

Do, Hoang Dang Khoa; Kim, Joo-Hwan

2017-01-01

Chloroplast genomes (cpDNA) are highly valuable resources for evolutionary studies of angiosperms, since they are highly conserved, are small in size, and play critical roles in plants. Slipped-strand mispairing (SSM) was assumed to be a mechanism for generating repeat units in cpDNA. However, research on the employment of different small repeated sequences through SSM events, which may induce the accumulation of distinct types of repeats within the same region in cpDNA, has not been documented. Here, we sequenced two chloroplast genomes from the endemic species Heloniopsis tubiflora (Korea) and Xerophyllum tenax (USA) to cover the gap between molecular data and explore "hot spots" for genomic events in Melanthiaceae. Comparative analysis of 23 complete cpDNA sequences revealed that there were different stages of deletion in the rps16 region across the Melanthiaceae. Based on the partial or complete loss of rps16 gene in cpDNA, we have firstly reported potential molecular markers for recognizing two sections ( Veratrum and Fuscoveratrum ) of Veratrum . Melathiaceae exhibits a significant change in the junction between large single copy and inverted repeat regions, ranging from trnH_GUG to a part of rps3 . Our results show an accumulation of tandem repeats in the rpl23-ycf2 regions of cpDNAs. Small conserved sequences exist and flank tandem repeats in further observation of this region across most of the examined taxa of Liliales. Therefore, we propose three scenarios in which different small repeated sequences were used during SSM events to generate newly distinct types of repeats. Occasionally, prior to the SSM process, point mutation event and double strand break repair occurred and induced the formation of initial repeat units which are indispensable in the SSM process. SSM may have likely occurred more frequently for short repeats than for long repeat sequences in tribe Parideae (Melanthiaceae, Liliales). Collectively, these findings add new evidence of dynamic results from SSM in chloroplast genomes which can be useful for further evolutionary studies in angiosperms. Additionally, genomics events in cpDNA are potential resources for mining molecular markers in Liliales.

Characterization and analysis of ribosomal proteins in two marine calanoid copepods

NASA Astrophysics Data System (ADS)

Yang, Feifei; Xu, Donghui; Zhuang, Yunyun; Huang, Yousong; Yi, Xiaoyan; Chen, Hongju; Liu, Guangxing; Zhang, Huan

2016-11-01

Copepods are among the most abundant and successful metazoans in the marine ecosystem. However, genomic resources related to fundamental cellular processes are still limited in this particular group of crustaceans. Ribosomal proteins are the building blocks of ribosomes, the primary site for protein synthesis. In this study, we characterized and analyzed the cDNAs of cytoplasmic ribosomal proteins (cRPs) of two calanoid copepods, Pseudodiaptomus poplesia and Acartia pacifica. We obtained 79 cRP cDNAs from P. poplesia and 67 from A. pacifica by cDNA library construction/sequencing and rapid amplification of cDNA ends. Analysis of the nucleic acid composition showed that the copepod cRP-encoding genes had higher GC content in the protein-coding regions (CDSs) than in the untranslated regions (UTRs), and single nucleotide repeats (>3 repeats) were common, with "A" repeats being the most frequent, especially in the CDSs. The 3'-UTRs of the cRP genes were significantly longer than the 5'-UTRs. Codon usage analysis showed that the third positions of the codons were dominated by C or G. The deduced amino acid sequences of the cRPs contained high proportions of positively charged residues and had high pI values. This is the first report of a complete set of cRP-encoding genes from copepods. Our results shed light on the characteristics of cRPs in copepods, and provide fundamental data for further studies of protein synthesis in copepods. The copepod cRP information revealed in this study indicates that additional comparisons and analysis should be performed on different taxonomic categories such as orders and families.

Ionic strength and temperature induced conformational changes in mononucleosomes and oligonucleosomes. [Chromatin

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

Schmitz, K.S.; Kent, J.C.; Parthasarathy, N.

1980-10-01

Chromatin is a nucleohistone complex which exhibits a repeat unit structure as inferred from nuclease digestion studies. The repeat unit, or nucleosome, is defined as approx. 200 base pairs of DNA wrapped about the surface of an octameric histone complex (two copies each of the histones H2A, H2B, H3, and H4). We report in this communication preliminary studies on the conformation of chromatin mononucleosomes and oligonucleosomes as a function of temperature and ionic strength. The methods used were conductivity, fluorescence of bound proflavine, and quasielastic light scattering.

Diesel Mechanics: Fundamentals.

ERIC Educational Resources Information Center

Foutes, William; And Others

This publication is the first in a series of three texts for a diesel mechanics curriculum. Its purpose is to teach the basic concepts related to employment in a diesel trade. Six sections contain 29 units. Each instructional unit includes some or all of these basic components: unit and specific (performance) objectives, suggested activities for…

Speech Motor Development: Integrating Muscles, Movements, and Linguistic Units

ERIC Educational Resources Information Center

Smith, Anne

2006-01-01

A fundamental problem for those interested in human communication is to determine how ideas and the various units of language structure are communicated through speaking. The physiological concepts involved in the control of muscle contraction and movement are theoretically distant from the processing levels and units postulated to exist in…

An approach for evaluating the repeatability of rapid wetland assessment methods: The effects of training and experience

EPA Science Inventory

We sampled 92 wetlands from four different basins in the United States to quantify observer repeatability in rapid wetland condition assessment using the Delaware Rapid Assessment Protocol (DERAP). In the Inland Bays basin of Delaware, 58 wetland sites were sampled by multiple ob...

Repeatability estimates for oleoresin yield measurements in three species of the southern pines

Treesearch

James H. Roberds; Brain L. Strom

2006-01-01

Repeatability was estimated for constitutive oleoresin yield measurements in 10 stands of three species of pines native to southeastern United States. Trees of these species that discharge large quantities of oleoresin upon wounding are considered to be most resistant to attack by southern pine beetle (Dendroctonus frontalis Zimmermann). Oleoresin...

METHODOLOGICAL NOTES: On the redefinition of the kilogram and ampere in terms of fundamental physical constants

NASA Astrophysics Data System (ADS)

Karshenboim, Savelii G.

2006-09-01

In the summer of 2005, a meeting of the Consultative Committee for Units of the International Committee on Weights and Measures took place. One of the topics discussed at the meeting was a possible redefinition of the kilogram in terms of fundamental physical constants — a question of relevance to a wide circle of specialists, from school teachers to physicists performing research in a great variety of fields. In this paper, the current situation regarding this question is briefly reviewed and its discussion at the Consultative Committee for Units and other bodies involved is covered. Other issues related to the International System of Units (SI) and broached at the meeting are also discussed.

A Department Chair: A Life Guard without a Life Jacket

ERIC Educational Resources Information Center

Gonaim, Faiza

2016-01-01

Leadership in higher education is fundamental for institutional development and sustainability in today's rapidly changing world. The academic department is a fundamental unit for transforming the university's visions and goals into reality. The vigorous contribution of each department, which depends in turn largely on the effectiveness of the…

Fundamentals of Diesel Engines.

ERIC Educational Resources Information Center

Marine Corps Inst., Washington, DC.

This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the fundamentals of diesel engine mechanics. Addressed in the three individual units of the course are the following topics: basic principles of diesel mechanics; principles, mechanics, and…

Mathematics: Essential to Marketing. Student's Manual and Teacher's Guide.

ERIC Educational Resources Information Center

Helton, Betty G.; Griffin, Jennie

This document contains both a student's manual and a teacher's guide for high school mathematics essential to marketing. The student's manual contains 34 assignments within the following 11 units: (1) arithmetic fundamentals; (2) application of arithmetic fundamentals; (3) cashiering; (4) inventory procedures; (5) invoices; (6) computing employee…

Fundamentals of Construction. Instructor Edition. Introduction to Construction Series.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This instructor's guide contains the materials required to teach a competency-based introductory course in the fundamentals of construction to students who have chosen to explore careers in construction. The following topics are covered in the course's 10 instructional units: industry orientation (exploring the construction industry and starting a…

Robust Prediction of Hydraulic Roughness

DTIC Science & Technology

2011-03-01

Manning’s n were required as input for further hydraulic analyses with HEC - RAS . HYDROCAL was applied to compare different estimates of resistance... River Restoration Science Synthesis (NRRSS) demonstrated that, in 2007, river and stream restoration projects and funding were at an all time high...behavior makes this parameter very difficult to quan- tify repeatedly and accurately. A fundamental concept of hydraulic theory in the context of river

Enhanced Teaching and Student Learning through a Simulator-Based Course in Chemical Unit Operations Design

ERIC Educational Resources Information Center

Ghasem, Nayef

2016-01-01

This paper illustrates a teaching technique used in computer applications in chemical engineering employed for designing various unit operation processes, where the students learn about unit operations by designing them. The aim of the course is not to teach design, but rather to teach the fundamentals and the function of unit operation processes…

Study Guide for Fundamentals of Solar Heating: A Correspondence Course for the Airconditioning Industry.

ERIC Educational Resources Information Center

Sheet Metal and Air Conditioning Contractors National Association, Vienna, VA.

This study guide groups eleven lessons into four study units. The first unit discusses the development and basic concepts of solar heating. The second unit deals with the nomenclature of the solar heating system. The third study unit covers sizing of the solar heating system to meet demand and discusses the operation of the total system. The…

Membrane vesiculation induced by proteins of the dengue virus envelope studied by molecular dynamics simulations.

PubMed

de Oliveira Dos Santos Soares, Ricardo; Bortot, Leandro Oliveira; van der Spoel, David; Caliri, Antonio

2017-12-20

Biological membranes are continuously remodeled in the cell by specific membrane-shaping machineries to form, for example, tubes and vesicles. We examine fundamental mechanisms involved in the vesiculation processes induced by a cluster of envelope (E) and membrane (M) proteins of the dengue virus (DENV) using molecular dynamics simulations and a coarse-grained model. We show that an arrangement of three E-M heterotetramers (EM 3 ) works as a bending unit and an ordered cluster of five such units generates a closed vesicle, reminiscent of the virus budding process. In silico mutagenesis of two charged residues of the anchor helices of the envelope proteins of DENV shows that Arg-471 and Arg-60 are fundamental to produce bending stress on the membrane. The fine-tuning between the size of the EM 3 unit and its specific bending action suggests this protein unit is an important factor in determining the viral particle size.

Membrane vesiculation induced by proteins of the dengue virus envelope studied by molecular dynamics simulations

NASA Astrophysics Data System (ADS)

de Oliveira dos Santos Soares, Ricardo; Oliveira Bortot, Leandro; van der Spoel, David; Caliri, Antonio

2017-12-01

Biological membranes are continuously remodeled in the cell by specific membrane-shaping machineries to form, for example, tubes and vesicles. We examine fundamental mechanisms involved in the vesiculation processes induced by a cluster of envelope (E) and membrane (M) proteins of the dengue virus (DENV) using molecular dynamics simulations and a coarse-grained model. We show that an arrangement of three E-M heterotetramers (EM3) works as a bending unit and an ordered cluster of five such units generates a closed vesicle, reminiscent of the virus budding process. In silico mutagenesis of two charged residues of the anchor helices of the envelope proteins of DENV shows that Arg-471 and Arg-60 are fundamental to produce bending stress on the membrane. The fine-tuning between the size of the EM3 unit and its specific bending action suggests this protein unit is an important factor in determining the viral particle size.

Independence of motor unit recruitment and rate modulation during precision force control.

PubMed

Kamen, G; Du, D C

1999-01-01

The vertebrate motor system chiefly employs motor unit recruitment and rate coding to modulate muscle force output. In this paper, we studied how the recruitment of new motor units altered the firing rate of already-active motor units during precision force production in the first dorsal interosseous muscle. Six healthy adults performed linearly increasing isometric voluntary contractions while motor unit activity and force output were recorded. After motor unit discharges were identified, motor unit firing rates were calculated before and after the instances of new motor unit recruitment. Three procedures were applied to compute motor unit firing rate, including the mean of a fixed number of inter-spike intervals and the constant width weighted Hanning window filter method, as well as a modified boxcar technique. In contrast to previous reports, the analysis of the firing rates of over 200 motor units revealed that reduction of the active firing rates was not a common mechanism used to accommodate the twitch force produced by the recruitment of a new motor unit. Similarly, during de-recruitment there was no tendency for motor unit firing rates to increase immediately following the cessation of activity in other motor units. Considerable consistency in recruitment behavior was observed during repeated contractions. However, firing rates during repeated contractions demonstrated considerably more fluctuation. It is concluded that the neuromuscular system does not use short-term preferential motor unit disfacilitation to effect precise regulation of muscular force output.

Rate-loss analysis of an efficient quantum repeater architecture

NASA Astrophysics Data System (ADS)

Guha, Saikat; Krovi, Hari; Fuchs, Christopher A.; Dutton, Zachary; Slater, Joshua A.; Simon, Christoph; Tittel, Wolfgang

2015-08-01

We analyze an entanglement-based quantum key distribution (QKD) architecture that uses a linear chain of quantum repeaters employing photon-pair sources, spectral-multiplexing, linear-optic Bell-state measurements, multimode quantum memories, and classical-only error correction. Assuming perfect sources, we find an exact expression for the secret-key rate, and an analytical description of how errors propagate through the repeater chain, as a function of various loss-and-noise parameters of the devices. We show via an explicit analytical calculation, which separately addresses the effects of the principle nonidealities, that this scheme achieves a secret-key rate that surpasses the Takeoka-Guha-Wilde bound—a recently found fundamental limit to the rate-vs-loss scaling achievable by any QKD protocol over a direct optical link—thereby providing one of the first rigorous proofs of the efficacy of a repeater protocol. We explicitly calculate the end-to-end shared noisy quantum state generated by the repeater chain, which could be useful for analyzing the performance of other non-QKD quantum protocols that require establishing long-distance entanglement. We evaluate that shared state's fidelity and the achievable entanglement-distillation rate, as a function of the number of repeater nodes, total range, and various loss-and-noise parameters of the system. We extend our theoretical analysis to encompass sources with nonzero two-pair-emission probability, using an efficient exact numerical evaluation of the quantum state propagation and measurements. We expect our results to spur formal rate-loss analysis of other repeater protocols and also to provide useful abstractions to seed analyses of quantum networks of complex topologies.

The bombardier beetle and its use of a pressure relief valve system to deliver a periodic pulsed spray.

PubMed

Beheshti, Novid; Mcintosh, Andy C

2007-12-01

In this paper the combustion chamber of the bombardier beetle is considered and recent findings are presented which demonstrate that certain parts of the anatomy are in fact inlet and outlet valves. In particular, the authors show that the intake and exhaust valve mechanism involves a repeated (pulsating) steam explosion, the principle of which was up till now unclear. New research here has now shown the characteristics of the ejections and the role of important valves. In this paper numerical simulations of the two-phase flow ejection are presented which demonstrate that the principle of cyclic water injection followed by water and steam decompression explosions is the fundamental mechanism used to create the repeated ejections.

Identification of Simple Sequence Repeats in Chloroplast Genomes of Magnoliids Through Bioinformatics Approach.

PubMed

Srivastava, Deepika; Shanker, Asheesh

2016-12-01

Basal angiosperms or Magnoliids is an important clade of commercially important plants which mainly include spices and edible fruits. In this study, 17 chloroplast genome sequences belonging to clade Magnoliids were screened for the identification of chloroplast simple sequence repeats (cpSSRs). Simple sequence repeats or microsatellites are short stretches of DNA up to 1-6 base pair in length. These repeats are ubiquitous and play important role in the development of molecular markers and to study the mapping of traits of economic, medical or ecological interest. A total of 479 SSRs were detected, showing average density of 1 SSR/6.91 kb. Depending on the repeat units, the length of SSRs ranged from 12 to 24 bp for mono-, 12 to 18 bp for di-, 12 to 26 bp for tri-, 12 to 24 bp for tetra-, 15 bp for penta- and 18 bp for hexanucleotide repeats. Mononucleotide repeats were the most frequent (207, 43.21 %) followed by tetranucleotide repeats (130, 27.13 %). Penta- and hexanucleotide repeats were least frequent or absent in these chloroplast genomes.

Linear biocompatible glyco-polyamidoamines as dual action mode virus infection inhibitors with potential as broad-spectrum microbicides for sexually transmitted diseases

NASA Astrophysics Data System (ADS)

Mauro, Nicolò; Ferruti, Paolo; Ranucci, Elisabetta; Manfredi, Amedea; Berzi, Angela; Clerici, Mario; Cagno, Valeria; Lembo, David; Palmioli, Alessandro; Sattin, Sara

2016-09-01

The initial steps of viral infections are mediated by interactions between viral proteins and cellular receptors. Blocking the latter with high-affinity ligands may inhibit infection. DC-SIGN, a C-type lectin receptor expressed by immature dendritic cells and macrophages, mediates human immunodeficiency virus (HIV) infection by recognizing mannose clusters on the HIV-1 gp120 envelope glycoprotein. Mannosylated glycodendrimers act as HIV entry inhibitors thanks to their ability to block this receptor. Previously, an amphoteric, but prevailingly cationic polyamidoamine named AGMA1 proved effective as infection inhibitor for several heparan sulfate proteoglycan-dependent viruses, such as human papilloma virus HPV-16 and herpes simplex virus HSV-2. An amphoteric, but prevailingly anionic PAA named ISA23 proved inactive. It was speculated that the substitution of mannosylated units for a limited percentage of AGMA1 repeating units, while imparting anti-HIV activity, would preserve the fundamentals of its HPV-16 and HSV-2 infection inhibitory activity. In this work, four biocompatible linear PAAs carrying different amounts of mannosyl-triazolyl pendants, Man-ISA7, Man-ISA14, Man-AGMA6.5 and Man-AGMA14.5, were prepared by reaction of 2-(azidoethyl)-α-D-mannopyranoside and differently propargyl-substituted AGMA1 and ISA23. All mannosylated PAAs inhibited HIV infection. Both Man-AGMA6.5 and Man-AGMA14.5 maintained the HPV-16 and HSV-2 activity of the parent polymer, proving broad-spectrum, dual action mode virus infection inhibitors.

Engineering customized TALE nucleases (TALENs) and TALE transcription factors by fast ligation-based automatable solid-phase high-throughput (FLASH) assembly.

PubMed

Reyon, Deepak; Maeder, Morgan L; Khayter, Cyd; Tsai, Shengdar Q; Foley, Jonathan E; Sander, Jeffry D; Joung, J Keith

2013-07-01

Customized DNA-binding domains made using transcription activator-like effector (TALE) repeats are rapidly growing in importance as widely applicable research tools. TALE nucleases (TALENs), composed of an engineered array of TALE repeats fused to the FokI nuclease domain, have been used successfully for directed genome editing in various organisms and cell types. TALE transcription factors (TALE-TFs), consisting of engineered TALE repeat arrays linked to a transcriptional regulatory domain, have been used to up- or downregulate expression of endogenous genes in human cells and plants. This unit describes a detailed protocol for the recently described fast ligation-based automatable solid-phase high-throughput (FLASH) assembly method. FLASH enables automated high-throughput construction of engineered TALE repeats using an automated liquid handling robot or manually using a multichannel pipet. Using the automated approach, a single researcher can construct up to 96 DNA fragments encoding TALE repeat arrays of various lengths in a single day, and then clone these to construct sequence-verified TALEN or TALE-TF expression plasmids in a week or less. Plasmids required for FLASH are available by request from the Joung lab (http://eGenome.org). This unit also describes improvements to the Zinc Finger and TALE Targeter (ZiFiT Targeter) web server (http://ZiFiT.partners.org) that facilitate the design and construction of FLASH TALE repeat arrays in high throughput. © 2013 by John Wiley & Sons, Inc.

Fundamental Dimensions and Essential Elements of Exemplary Local Extension Units

ERIC Educational Resources Information Center

Terry, Bryan D.; Osborne, Edward

2015-01-01

Collaborative efforts between federal, state, and local government agencies enable local Extension units to deliver a high level of educational opportunities to local citizens. These units represent land-grant institutions by delivering non-formal education that aim to address local, regional, and state concerns. The purpose of this study was to…

Learning on Demand: Online Education in the United States, 2009

ERIC Educational Resources Information Center

Allen, I. Elaine; Seaman, Jeff

2010-01-01

"Learning on Demand: Online Education in the United States, 2009" represents the seventh annual report on the state of online learning among higher education institutions in the United States. The study is aimed at answering some of the fundamental questions about the nature and extent of online education. Based on responses from over…

Aggregating quantum repeaters for the quantum internet

NASA Astrophysics Data System (ADS)

Azuma, Koji; Kato, Go

2017-09-01

The quantum internet holds promise for accomplishing quantum teleportation and unconditionally secure communication freely between arbitrary clients all over the globe, as well as the simulation of quantum many-body systems. For such a quantum internet protocol, a general fundamental upper bound on the obtainable entanglement or secret key has been derived [K. Azuma, A. Mizutani, and H.-K. Lo, Nat. Commun. 7, 13523 (2016), 10.1038/ncomms13523]. Here we consider its converse problem. In particular, we present a universal protocol constructible from any given quantum network, which is based on running quantum repeater schemes in parallel over the network. For arbitrary lossy optical channel networks, our protocol has no scaling gap with the upper bound, even based on existing quantum repeater schemes. In an asymptotic limit, our protocol works as an optimal entanglement or secret-key distribution over any quantum network composed of practical channels such as erasure channels, dephasing channels, bosonic quantum amplifier channels, and lossy optical channels.

Individual variation and repeatability of basal metabolism in the bank vole, Clethrionomys glareolus.

PubMed Central

Labocha, Marta K.; Sadowska, Edyta T.; Baliga, Katarzyna; Semer, Aleksandra K.; Koteja, Paweł

2004-01-01

Basal metabolic rate (BMR) is a fundamental energetic trait and has been measured in hundreds of birds and mammals. Nevertheless, little is known about the consistency of the population-average BMR or its repeatability at the level of individual variation. Here, we report that average mass-independent BMR did not differ between two generations of bank voles or between two trials separated by one month. Individual differences in BMR were highly repeatable across the one month interval: the coefficient of intraclass correlation was 0.70 for absolute log-transformed values and 0.56 for mass-independent values. Thus, BMR can be a meaningful measure of an individual physiological characteristic and can be used to test hypotheses concerning relationships between BMR and other traits. On the other hand, mass-independent BMR did not differ significantly across families, and the coefficient of intraclass correlation for full sibs did not differ from zero, which suggests that heritability of BMR in voles is not high. PMID:15101695

On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem

PubMed Central

Li, Jiawei; Kendall, Graham

2015-01-01

In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games. PMID:26288088

3 CFR 8589 - Proclamation 8589 of October 22, 2010. United Nations Day, 2010

Code of Federal Regulations, 2011 CFR

2011-01-01

... devastating wars to rededicate themselves to peace, justice, and progress. The founders of the United Nations vowed to work together to ensure that the horrors seen in World War II would never be repeated. On... 3 The President 1 2011-01-01 2011-01-01 false Proclamation 8589 of October 22, 2010. United...

Longleaf pine site response to repeated fertilization and forest floor removal by raking and prescribed burning

Treesearch

Kim Ludovici; Robert Eaton; Stanley Zarnoch

2018-01-01

Removal of forest floor litter by pine needle raking and prescribed burning is a common practice in longleaf pine (Pinus palustris Mill.) stands on Coastal Plain sites in the Southeastern United States. Repeated removal of litter by raking and the loss of surface organic matter from controlled burns can affect the...

Effects of repeated burning on snag abundance in shortleaf pine woodlands

Treesearch

Roger W. Perry; Phillip N. Jordan; Virginia L. McDaniel

2017-01-01

Forest managers are restoring and maintaining forest woodlands across substantial areas of the United States, and these efforts typically require the use of frequent prescribed fire. The effects of frequent prescribed fire on important habitat components such as snags remain unknown. We conducted a study to determine how snag densities are affected by repeated...

Is mammalian chromosomal evolution driven by regions of genome fragility?

PubMed Central

Ruiz-Herrera, Aurora; Castresana, Jose; Robinson, Terence J

2006-01-01

Background A fundamental question in comparative genomics concerns the identification of mechanisms that underpin chromosomal change. In an attempt to shed light on the dynamics of mammalian genome evolution, we analyzed the distribution of syntenic blocks, evolutionary breakpoint regions, and evolutionary breakpoints taken from public databases available for seven eutherian species (mouse, rat, cattle, dog, pig, cat, and horse) and the chicken, and examined these for correspondence with human fragile sites and tandem repeats. Results Our results confirm previous investigations that showed the presence of chromosomal regions in the human genome that have been repeatedly used as illustrated by a high breakpoint accumulation in certain chromosomes and chromosomal bands. We show, however, that there is a striking correspondence between fragile site location, the positions of evolutionary breakpoints, and the distribution of tandem repeats throughout the human genome, which similarly reflect a non-uniform pattern of occurrence. Conclusion These observations provide further evidence that certain chromosomal regions in the human genome have been repeatedly used in the evolutionary process. As a consequence, the genome is a composite of fragile regions prone to reorganization that have been conserved in different lineages, and genomic tracts that do not exhibit the same levels of evolutionary plasticity. PMID:17156441

Repeatability of testing a small broadband sensor in the Albuquerque Seismological Laboratory Underground Vault

USGS Publications Warehouse

Ringler, Adam; Holland, Austin; Wilson, David

2017-01-01

Variability in seismic instrumentation performance plays a fundamental role in our ability to carry out experiments in observational seismology. Many such experiments rely on the assumed performance of various seismic sensors as well as on methods to isolate the sensors from nonseismic noise sources. We look at the repeatability of estimating the self‐noise, midband sensitivity, and the relative orientation by comparing three collocated Nanometrics Trillium Compact sensors. To estimate the repeatability, we conduct a total of 15 trials in which one sensor is repeatedly reinstalled, alongside two undisturbed sensors. We find that we are able to estimate the midband sensitivity with an error of no greater than 0.04% with a 99th percentile confidence, assuming a standard normal distribution. We also find that we are able to estimate mean sensor self‐noise to within ±5.6  dB with a 99th percentile confidence in the 30–100‐s‐period band. Finally, we find our relative orientation errors have a mean difference in orientation of 0.0171° from the reference, but our trials have a standard deviation of 0.78°.

ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. BASIC ELECTRICITY, UNIT 3, ASSIGNMENTS.

ERIC Educational Resources Information Center

SUTTON, MACK C.

THIS GUIDE IS FOR INDIVIDUAL STUDENT USE IN STUDYING BASIC ELECTRICAL FUNDAMENTALS IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. THE COURSE OBJECTIVE IS TO DEVELOP AN UNDERSTANDING OF DIRECT CURRENT FUNDAMENTALS. EACH OF THE 10 ASSIGNMENT SHEETS PROVIDES THE LESSON SUBJECT, PURPOSE,…

Integration of Skills and Competencies in the Missouri Marketing Education Core Curriculum. Section II.

ERIC Educational Resources Information Center

Ruhland, Sheila K.; Wilkinson, Richard F.

This publication contains teaching activities for the Fundamentals of Marketing and Advanced Marketing curriculum. Chapter 1 presents an alignment of the marketing education core competencies within the nine curriculum units for Fundamentals of Marketing and Advanced Marketing as they relate to the basic academic skills, advanced academic skills,…

ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. BASIC ELECTRICITY, UNIT 2, ASSIGNMENTS.

ERIC Educational Resources Information Center

SUTTON, MACK C.

THIS GUIDE IS FOR INDIVIDUAL STUDENT USE IN STUDYING BASIC ELECTRICAL FUNDAMENTALS IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. THE COURSE OBJECTIVE IS TO DEVELOP AN UNDERSTANDING OF DIRECT CURRENT FUNDAMENTALS. EACH OF THE 15 ASSIGNMENT SHEETS PROVIDES THE LESSON SUBJECT, PURPOSE,…

What Is a Leaf? An Online Tutorial and Tests

ERIC Educational Resources Information Center

Burrows, Geoffrey

2008-01-01

A leaf is a fundamental unit in botany and understanding what constitutes a leaf is fundamental to many plant science activities. My observations and subsequent testing indicated that many students could not confidently and consistently recognise a leaf from a leaflet, or recognise basic leaf arrangements and the various types of compound or…

Direct mapping of symbolic DNA sequence into frequency domain in global repeat map algorithm

PubMed Central

Glunčić, Matko; Paar, Vladimir

2013-01-01

The main feature of global repeat map (GRM) algorithm (www.hazu.hr/grm/software/win/grm2012.exe) is its ability to identify a broad variety of repeats of unbounded length that can be arbitrarily distant in sequences as large as human chromosomes. The efficacy is due to the use of complete set of a K-string ensemble which enables a new method of direct mapping of symbolic DNA sequence into frequency domain, with straightforward identification of repeats as peaks in GRM diagram. In this way, we obtain very fast, efficient and highly automatized repeat finding tool. The method is robust to substitutions and insertions/deletions, as well as to various complexities of the sequence pattern. We present several case studies of GRM use, in order to illustrate its capabilities: identification of α-satellite tandem repeats and higher order repeats (HORs), identification of Alu dispersed repeats and of Alu tandems, identification of Period 3 pattern in exons, implementation of ‘magnifying glass’ effect, identification of complex HOR pattern, identification of inter-tandem transitional dispersed repeat sequences and identification of long segmental duplications. GRM algorithm is convenient for use, in particular, in cases of large repeat units, of highly mutated and/or complex repeats, and of global repeat maps for large genomic sequences (chromosomes and genomes). PMID:22977183

Rapid and accurate synthesis of TALE genes from synthetic oligonucleotides.

PubMed

Wang, Fenghua; Zhang, Hefei; Gao, Jingxia; Chen, Fengjiao; Chen, Sijie; Zhang, Cuizhen; Peng, Gang

2016-01-01

Custom synthesis of transcription activator-like effector (TALE) genes has relied upon plasmid libraries of pre-fabricated TALE-repeat monomers or oligomers. Here we describe a novel synthesis method that directly incorporates annealed synthetic oligonucleotides into the TALE-repeat units. Our approach utilizes iterative sets of oligonucleotides and a translational frame check strategy to ensure the high efficiency and accuracy of TALE-gene synthesis. TALE arrays of more than 20 repeats can be constructed, and the majority of the synthesized constructs have perfect sequences. In addition, this novel oligonucleotide-based method can readily accommodate design changes to the TALE repeats. We demonstrated an increased gene targeting efficiency against a genomic site containing a potentially methylated cytosine by incorporating non-conventional repeat variable di-residue (RVD) sequences.

Depressive Symptoms and Violence Exposure: Contributors to Repeat Pregnancies Among Adolescents

PubMed Central

Anderson, Cheryl A.; Pierce, Lisa

2015-01-01

ABSTRACT Depressive symptoms and violence exposure (VE) often cooccur and have been recognized to influence childbearing; contribution to repeat pregnancy is unclear and examined in this article. This cross-sectional, descriptive, study screened for depressive symptoms and VE among 193 adolescent mothers at a large county hospital in Southwestern United States. Repeat pregnancy and depressive symptoms characterized one-third and one-quarter of adolescents, respectively. Despite minimal disclosure of VE, repeat pregnancy was significantly influenced by child abuse and past traumatic life experiences. Assessments and interventions with adolescents should focus on frequency of repeat pregnancies and symptoms of depression and VE. Nurses and childbirth educators are poised to offer birth control information and education, support, and resources highlighting depression and VE to adolescents. PMID:26834444

Patients with acute abdominal pain describe their experiences of fundamental care across the acute care episode: a multi-stage qualitative case study.

PubMed

Jangland, Eva; Kitson, Alison; Muntlin Athlin, Åsa

2016-04-01

To explore how patients with acute abdominal pain describe their experiences of fundamental care across the acute care episode. Acute abdominal pain is one of the most common conditions to present in the acute care setting. Little is known about how patients' fundamental care needs are managed from presentation to post discharge. A multi-stage qualitative case study using the Fundamentals of Care framework as the overarching theoretical and explanatory mechanism. Repeated reflective interviews were conducted with five adult patients over a 6-month period in 2013 at a university hospital in Sweden. The interviews (n = 14) were analysed using directed content analysis. Patients' experiences across the acute care episode are presented as five patient narratives and synthesized into five descriptions of the entire hospital journey. The patients talked about the fundamentals of care and had vivid accounts of what they meant to them. The experiences of each of the patients were influenced by the extent to which they felt engaged with the health professionals. The ability to engage or build a rapport was identified as a central component across the fundamental care elements, but it varied in visibility. Consistent pain management, comfort, timely and accurate information, choice and dignity and relationships were identified as essential fundamental care needs of patients experiencing acute abdominal pain regardless of setting, diagnosis, or demographic variables. These were variously achieved and the patients' narratives raised areas for improvement in several areas. © 2016 John Wiley & Sons Ltd.

Chemical synthesis of the tetrasaccharide repeating unit of the O-polysaccharide isolated from Azospirillum brasilense SR80.

PubMed

Sarkar, Vikramjit; Mukhopadhyay, Balaram

2015-04-10

A linear strategy has been developed for the synthesis of the tetrasaccharide repeating unit of the O-polysaccharide from Azospirillum brasilense SR80. Stepwise glycosylation of the rationally protected thioglycoside donors activated by NIS in the presence of La(OTf)3 furnished the target tetrasaccharide. The glycosylation reactions resulted in the formation of the desired linkage with absolute stereoselectivity and afforded the required derivatives in good to excellent yields. The phthalimido group has been used as the precursor of the desired acetamido group to meet the requirement of 1,2-trans glycosidic linkage. Copyright © 2015 Elsevier Ltd. All rights reserved.

Iron balance in the red blood cell donor.

PubMed

Brittenham, G M

2005-01-01

Phlebotomy of a unit of blood produces a loss of 200 to 250 mg of iron in haemoglobin. Because of physiological differences in iron balance between women of childbearing age and men, the loss of similar amounts of iron at donation has divergent consequences for committed donors. Women of childbearing age have an increased risk of iron deficiency if they donate more than one unit per year while men are usually able to maintain iron balance while donating four or more units of blood per year. Lack of iron is the most important medical reason for deferral from repeat donation and primarily affects women of childbearing age. Deferral of these women discourages them from further donation and may lead to their loss as donors. Provisions for blood donation should protect those who give blood from adverse consequences of their altruism. Safe and effective approaches to iron replacement after donation have been developed that can prevent iron deficiency in women who give blood repeatedly. Blood centres should consider incorporating programmes of iron replacement for women of childbearing age who give blood repeatedly to protect these donors against iron deficiency and to enhance their retention and commitment as dedicated donors.

A model of high-affinity antibody binding to type III group B Streptococcus capsular polysaccharide.

PubMed

Wessels, M R; Muñoz, A; Kasper, D L

1987-12-01

We recently reported that the single repeating-unit pentasaccharide of type III group B Streptococcus (GBS) capsular polysaccharide is only weakly reactive with type III GBS antiserum. To further elucidate the relationship between antigen-chain length and antigenicity, tritiated oligosaccharides derived from type III capsular polysaccharide were used to generate detailed saturation binding curves with a fixed concentration of rabbit antiserum in a radioactive antigen-binding assay. A graded increase in affinity of antigen-antibody binding was seen as oligosaccharide size increased from 2.6 repeating units to 92 repeating units. These differences in affinity of antibody binding to oligosaccharides of different molecular size were confirmed by immunoprecipitation and competitive ELISA, two independent assays of antigen-antibody binding. Analysis of the saturation binding experiment indicated a difference of 300-fold in antibody-binding affinity for the largest versus the smallest tested oligosaccharides. Unexpectedly, the saturation binding values approached by the individual curves were inversely related to oligosaccharide chain length on a molar basis but equivalent on a weight basis. This observation is compatible with a model in which binding of an immunoglobulin molecule to an antigenic site on the polysaccharide facilitates subsequent binding of antibody to that antigen.

The fundamental units, processes and patterns of evolution, and the Tree of Life conundrum

PubMed Central

Koonin, Eugene V; Wolf, Yuri I

2009-01-01

Background The elucidation of the dominant role of horizontal gene transfer (HGT) in the evolution of prokaryotes led to a severe crisis of the Tree of Life (TOL) concept and intense debates on this subject. Concept Prompted by the crisis of the TOL, we attempt to define the primary units and the fundamental patterns and processes of evolution. We posit that replication of the genetic material is the singular fundamental biological process and that replication with an error rate below a certain threshold both enables and necessitates evolution by drift and selection. Starting from this proposition, we outline a general concept of evolution that consists of three major precepts. 1. The primary agency of evolution consists of Fundamental Units of Evolution (FUEs), that is, units of genetic material that possess a substantial degree of evolutionary independence. The FUEs include both bona fide selfish elements such as viruses, viroids, transposons, and plasmids, which encode some of the information required for their own replication, and regular genes that possess quasi-independence owing to their distinct selective value that provides for their transfer between ensembles of FUEs (genomes) and preferential replication along with the rest of the recipient genome. 2. The history of replication of a genetic element without recombination is isomorphously represented by a directed tree graph (an arborescence, in the graph theory language). Recombination within a FUE is common between very closely related sequences where homologous recombination is feasible but becomes negligible for longer evolutionary distances. In contrast, shuffling of FUEs occurs at all evolutionary distances. Thus, a tree is a natural representation of the evolution of an individual FUE on the macro scale, but not of an ensemble of FUEs such as a genome. 3. The history of life is properly represented by the "forest" of evolutionary trees for individual FUEs (Forest of Life, or FOL). Search for trends and patterns in the FOL is a productive direction of study that leads to the delineation of ensembles of FUEs that evolve coherently for a certain time span owing to a shared history of vertical inheritance or horizontal gene transfer; these ensembles are commonly known as genomes, taxa, or clades, depending on the level of analysis. A small set of genes (the universal genetic core of life) might show a (mostly) coherent evolutionary trend that transcends the entire history of cellular life forms. However, it might not be useful to denote this trend "the tree of life", or organismal, or species tree because neither organisms nor species are fundamental units of life. Conclusion A logical analysis of the units and processes of biological evolution suggests that the natural fundamental unit of evolution is a FUE, that is, a genetic element with an independent evolutionary history. Evolution of a FUE on the macro scale is naturally represented by a tree. Only the full compendium of trees for individual FUEs (the FOL) is an adequate depiction of the evolution of life. Coherent evolution of FUEs over extended evolutionary intervals is a crucial aspect of the history of life but a "species" or "organismal" tree is not a fundamental concept. Reviewers This articles was reviewed by Valerian Dolja, W. Ford Doolittle, Nicholas Galtier, and William Martin PMID:19788730

Diverticular disease of the colon does not increase risk of repeat C. difficile infection.

PubMed

Feuerstadt, Paul; Das, Rohit; Brandt, Lawrence J

2013-01-01

Studies have suggested that colonic diverticulosis might increase the likelihood of repeat Clostridium difficile infection (CDI). Our study was designed to compare rates of repeat infection in patients with and without colon diverticula. Patients who had a positive C. difficile toxin assay and colonoscopic evidence of diverticulosis were classified as CDI and diverticulosis (CDI-D), whereas those with a positive toxin assay but no such colonoscopic evidence were classified as CDI and no diverticulosis (CDI-ND). Various clinical and epidemiologic factors were recorded for each patient. Primary outcomes were "relapse" (repeat CDI within 3 mo of initial infection) and "recurrent" infection (repeat CDI≥3 mo after initial infection). Secondary outcomes 30 days after diagnosis were mortality, intensive care unit transfer, and continuous hospitalization. A total of 128 patients were classified as CDI-D, whereas 137 had CDI-ND. There were no significant differences between CDI-D and CDI-ND when comparing frequencies of repeat infection and its subclassifications, relapse or recurrence. There were, however, statistical associations seen between diverticulosis of the ascending colon and increased recurrence rates [hazard ratio (HR): 1.4±0.38, P<0.05] and decreased rates of relapse in diverticular disease of the descending (HR: 0.40±0.46, P<0.05), and sigmoid colon (HR: 0.39±0.49, P<0.05). The ascending colon association is limited by a small patient population. There were no significant differences in any of the 30-day outcomes including intensive care unit requirement, hospitalization stay, or mortality. Patients with diverticular disease of the colon are not at increased risk of repeat CDI.

Molecular structure and chromosome distribution of three repetitive DNA families in Anemone hortensis L. (Ranunculaceae).

PubMed

Mlinarec, Jelena; Chester, Mike; Siljak-Yakovlev, Sonja; Papes, Drazena; Leitch, Andrew R; Besendorfer, Visnja

2009-01-01

The structure, abundance and location of repetitive DNA sequences on chromosomes can characterize the nature of higher plant genomes. Here we report on three new repeat DNA families isolated from Anemone hortensis L.; (i) AhTR1, a family of satellite DNA (stDNA) composed of a 554-561 bp long EcoRV monomer; (ii) AhTR2, a stDNA family composed of a 743 bp long HindIII monomer and; (iii) AhDR, a repeat family composed of a 945 bp long HindIII fragment that exhibits some sequence similarity to Ty3/gypsy-like retroelements. Fluorescence in-situ hybridization (FISH) to metaphase chromosomes of A. hortensis (2n = 16) revealed that both AhTR1 and AhTR2 sequences co-localized with DAPI-positive AT-rich heterochromatic regions. AhTR1 sequences occur at intercalary DAPI bands while AhTR2 sequences occur at 8-10 terminally located heterochromatic blocks. In contrast AhDR sequences are dispersed over all chromosomes as expected of a Ty3/gypsy-like element. AhTR2 and AhTR1 repeat families include polyA- and polyT-tracks, AT/TA-motifs and a pentanucleotide sequence (CAAAA) that may have consequences for chromatin packing and sequence homogeneity. AhTR2 repeats also contain TTTAGGG motifs and degenerate variants. We suggest that they arose by interspersion of telomeric repeats with subtelomeric repeats, before hybrid unit(s) amplified through the heterochromatic domain. The three repetitive DNA families together occupy approximately 10% of the A. hortensis genome. Comparative analyses of eight Anemone species revealed that the divergence of the A. hortensis genome was accompanied by considerable modification and/or amplification of repeats.

Microevolution of Pandemic Vibrio parahaemolyticus Assessed by the Number of Repeat Units in Short Sequence Tandem Repeat Regions

PubMed Central

García, Katherine; Gavilán, Ronnie G.; Höfle, Manfred G.; Martínez-Urtaza, Jaime; Espejo, Romilio T.

2012-01-01

The emergence of the pandemic strain Vibrio parahaemolyticus O3:K6 in 1996 caused a large increase of diarrhea outbreaks related to seafood consumption in Southeast Asia, and later worldwide. Isolates of this strain constitutes a clonal complex, and their effectual differentiation is possible by comparison of their variable number tandem repeats (VNTRs). The differentiation of the isolates by the differences in VNTRs will allow inferring the population dynamics and microevolution of this strain but this requires knowing the rate and mechanism of VNTRs' variation. Our study of mutants obtained after serial cultivation of clones showed that mutation rates of the six VNTRs examined are on the order of 10−4 mutant per generation and that difference increases by stepwise addition of single mutations. The single stepwise mutation (SSM) was deduced because mutants with 1, 2, 3, or more repeat unit deletions or insertions follow a geometric distribution. Plausible phylogenetic trees are obtained when, according to SSM, the genetic distance between clusters with different number of repeats is assessed by the absolute differences in repeats. Using this approach, mutants originated from different isolates of pandemic V. parahaemolyticus after serial cultivation are clustered with their parental isolates. Additionally, isolates of pandemic V. parahaemolyticus from Southeast Asia, Tokyo, and northern and southern Chile are clustered according their geographical origin. The deepest split in these four populations is observed between the Tokyo and southern Chile populations. We conclude that proper phylogenetic relations and successful tracing of pandemic V. parahaemolyticus requires measuring the differences between isolates by the absolute number of repeats in the VNTRs considered. PMID:22292049

Methods Engineering Workshop for the Shipbuilding Industry

DTIC Science & Technology

1985-09-01

physiological process that reduces the performance capacity and motivation of humans sub- jected to excessive or repeated work stresses. fatigue allowance, Time...often involves basic business fundamentals, motivation , common sense, and the plain hard work of one person doing something. But the accomplishment that...utilize a batch mode form. ” (3) SERGE A. BIRN HAS A TRAINING SCHOOL IN CINCINNATI FOR MTM, MSD, MCD, MOTIVATION -PRODUCTIVITY , TIME STUDY, METHODS

Pramipexole-induced disruption of behavioral processes fundamental to intertemporal choice.

PubMed

Johnson, Patrick S; Stein, Jeffrey S; Smits, Rochelle R; Madden, Gregory J

2013-05-01

Evaluating the effects of presession drug administration on intertemporal choice in nonhumans is a useful approach for identifying compounds that promote impulsive behavior in clinical populations, such as those prescribed the dopamine agonist pramipexole (PPX). Based on the results of previous studies, it is unclear whether PPX increases rats' impulsive choice or attenuates aspects of stimulus control. The present study was designed to experimentally isolate behavioral processes fundamental to intertemporal choice and challenge them pharmacologically with PPX administration. In Experiment 1, the hypothesis that PPX increases impulsive choice as a result of enhanced sensitivity to reinforcer delays was tested and disconfirmed. That is, acute PPX diminished delay sensitivity in a manner consistent with disruption of stimulus control whereas repeated PPX had no effect on delay sensitivity. Experiments 2 and 3 elaborated upon this finding by examining the effects of repeated PPX on rats' discrimination of response-reinforcer contingencies and reinforcer amounts, respectively. Accuracy of both discriminations was reduced by PPX. Collectively these results provide no support for past studies that have suggested PPX increases impulsive choice. Instead, PPX impairs stimulus control over choice behavior. The behavioral approach adopted herein could be profitably integrated with genetic and other biobehavioral models to advance our understanding of impulsive behavior associated with drug administration. © Society for the Experimental Analysis of Behavior.

Tandemly repeated sequences in mtDNA control region of whitefish, Coregonus lavaretus.

PubMed

Brzuzan, P

2000-06-01

Length variation of the mitochondrial DNA control region was observed with PCR amplification of a sample of 138 whitefish (Coregonus lavaretus). Nucleotide sequences of representative PCR products showed that the variation was due to the presence of an approximately 100-bp motif tandemly repeated two, three, or five times in the region between the conserved sequence block-3 (CSB-3) and the gene for phenylalanine tRNA. This is the first report on the tandem array composed of long repeat units in mitochondrial DNA of salmonids.

Contribution of wetlands to nitrate removal at the watershed scale

NASA Astrophysics Data System (ADS)

Hansen, Amy T.; Dolph, Christine L.; Foufoula-Georgiou, Efi; Finlay, Jacques C.

2018-02-01

Intensively managed row crop agriculture has fundamentally changed Earth surface processes within the Mississippi River basin through large-scale alterations of land cover, hydrology and reactive nitrogen availability. These changes have created leaky landscapes where excess agriculturally derived nitrate degrades riverine water quality at local, regional and continental scales. Individually, wetlands are known to remove nitrate but the conditions under which multiple wetlands meaningfully reduce riverine nitrate concentration have not been established. Only one region of the Mississippi River basin—the 44,000 km2 Minnesota River basin—still contains enough wetland cover within its intensively agriculturally managed watersheds to empirically address this question. Here we combine high-resolution land cover data for the Minnesota River basin with spatially extensive repeat water sampling data. By clearly isolating the effect of wetlands from crop cover, we show that, under moderate-high streamflow, wetlands are five times more efficient per unit area at reducing riverine nitrate concentration than the most effective land-based nitrogen mitigation strategies, which include cover crops and land retirement. Our results suggest that wetland restorations that account for the effects of spatial position in stream networks could provide a much greater benefit to water quality then previously assumed.

["Lex Kendra" in New York, United States. Homicide, "revolving door psychiatry" and political response].

PubMed

Röttgers, H R; Nedjat, S

2001-03-01

The history, motivation and consequences of the New York State "Kendra's Law" as of August 1999 are reviewed. "Kendra's Law" was the consequence of the killing of a young woman, Kendra W., by a schizophrenic patient later convicted for second degree murder. Before, he had been repeatedly rejected when he sought treatment in state-run psychiatric facilities and was expelled several times from long-term hospitals despite a long history of violent behaviour when untreated. "Kendra's Law" now entitles physicians, case workers, roommates and families of untreated mentally ill persons to seek a court order forcing a patient to comply with treatment and, at the same time, compelling mental health institutions to grant this treatment. Additionally, the law and another bill signed in November 1999 provided for additional funding for the underfinanced state-run mental health system. "Kendra's Law" illustrates a bidirectional attempt to cope with the revolving door treatment situation of mentally ill in the State of New York by additional funding and additional possibilities to enforce treatment. The law illustrates the fundamental conflict between individual autonomy and the need for treatment of people suffering from severe mental illness.

The nucleosome: orchestrating DNA damage signaling and repair within chromatin.

PubMed

Agarwal, Poonam; Miller, Kyle M

2016-10-01

DNA damage occurs within the chromatin environment, which ultimately participates in regulating DNA damage response (DDR) pathways and repair of the lesion. DNA damage activates a cascade of signaling events that extensively modulates chromatin structure and organization to coordinate DDR factor recruitment to the break and repair, whilst also promoting the maintenance of normal chromatin functions within the damaged region. For example, DDR pathways must avoid conflicts between other DNA-based processes that function within the context of chromatin, including transcription and replication. The molecular mechanisms governing the recognition, target specificity, and recruitment of DDR factors and enzymes to the fundamental repeating unit of chromatin, i.e., the nucleosome, are poorly understood. Here we present our current view of how chromatin recognition by DDR factors is achieved at the level of the nucleosome. Emerging evidence suggests that the nucleosome surface, including the nucleosome acidic patch, promotes the binding and activity of several DNA damage factors on chromatin. Thus, in addition to interactions with damaged DNA and histone modifications, nucleosome recognition by DDR factors plays a key role in orchestrating the requisite chromatin response to maintain both genome and epigenome integrity.

Between welfare medicine and mainstream entitlement: Medicaid at the political crossroads.

PubMed

Grogan, Colleen; Patashnik, Eric

2003-10-01

As the new century begins, the Medicaid program is arguably at a political crossroads. Over the 1980s and 1990s, policy makers enacted major expansions in Medicaid coverage, offering significant new health benefits to poor women and children and other constituencies. In elite rhetoric and political framing, Medicaid was increasingly cast as a broad-based social welfare entitlement of value to all Americans, including middle-class citizens. Some health care advocates began viewing Medicaid expansions as a potential path to achieving universal coverage in the United States. Yet Medicaid remains a means-tested program that has been repeatedly threatened with policy retrenchment. In this essay, we scrutinize Medicaid's current status and future possibilities from a historical-institutional perspective by tracing its complex evolution since its enactment in the Social Security Amendments of 1965. Our core claim is that decisions made at the time of Medicaid's original adoption have fundamentally set the matrix for struggles over the program's unfolding development. We demonstrate that key ambiguities embedded in the 1965 act created largely unintended opportunities for policy entrepreneurs to broaden Medicaid's scale and scope as well as foreseeable vulnerabilities that must be overcome if Medicaid is to realize its full potential.

Lower Critical Solution Temperature (LCST) and drug conjugation of polyacetal

NASA Astrophysics Data System (ADS)

de Silva, Chathuranga; Samanta, Sanjoy; Leophairatana, Porakrit; Koberstein, Jeffrey

There has been an increasing focus in polymer research for materials that can efficiently deliver therapeutics to a pre-identified solid tumor target. Due to their unique properties, stimuli responsive polymers (SRPs) have been of particular interest. One such novel SRP is a polyacetal-based copolymer (PAC). PAC shows a remarkable temperature response (LCST) that is linearly dependent on composition. Here, we discuss the fundamental physical origins of this LCST behavior, exhibited by this polymer. Our results indicate that the observed LCST scales linearly with the number of carbon and oxygen atoms in the polymer repeat units, allowing for precise control over the LCST. We design PAC to include cancer therapeutics in its polymer-backbone, utilizing strategies to modify step-growth polymerization to obtain, for the first time, temperature-responsive main-chain drug conjugates. The temperature response in these main-chain drug conjugates allow for effective delivery of therapeutics to the tumor site, followed by acid-hydrolysis in acidic local tumor environments, to release pristine therapeutics directly at the tumor site. Due to these reasons, we foresee PAC to be in the forefront of soft-matter SRP drug-delivery systems.

ARS Nursery and Floricultural Crop Research in Ohio

USDA-ARS?s Scientific Manuscript database

The Application Technology Research Unit is the largest multidisciplinary research team in the United States Department of Agriculture, Agricultural Research Service, conducting studies on floricultural and nursery crops. On-farm research, part of ATRU Mission to conduct fundamental and development...

History Repeats Itself at Yorktown Middle.

ERIC Educational Resources Information Center

Haskin, Teresa T.

1999-01-01

Describes two interdisciplinary units that can be used in most middle school classrooms, one on the sinking of the "Titanic" and one on Pickett's charge at Gettysburg during the Civil War. Describes how each unit involves English, math, social studies, and science classes and activities. (SR)

An examination of elicitation method on fundamental frequency and repeatability of average airflow measures in children age 4:0-5:11 years.

PubMed

Brehm, Susan Baker; Weinrich, Barbara D; Sprouse, Dana C; May, Shelley K; Hughes, Michael R

2012-11-01

The purpose of this study was to determine the effect of task type on fundamental frequency (F(0)) and the short-term repeatability of average airflow values in preschool/kindergarten-age children. Prospective, experimental. Thirty healthy children (age 4.0-5.11 years) were included in this study. Participants completed three tasks (sustained vowel, counting, and storytelling) used to elicit measurements of F(0). With a 10-minute interval, participants also completed two trials of sustained /a/ at a comfortable pitch and loudness level for the measurement of average airflow rate. F(0) and intensity of the vowel production were recorded for both trials. A repeated measures analysis of variance revealed a significant main effect for task type elicitation on F(0) values (P=0.0003). A significant difference between elicitation tasks for F(0) was observed in the comparison of the counting and storytelling task (P<0.0001). A paired t test revealed no significant difference in average airflow rate across two trials (P=0.872). The change in F(0) and intensity was measured across the trials, and separate analyses of covariance revealed that these changes did not significantly influence average airflow values, (P=0.809) and (P=0.365), respectively. The results of this study demonstrated that F(0) may be influenced by task type in young children. Average airflow values appear to be stable over a short time period. This information is important in determining methods of evaluation and the reliability of instrumental measures in young children with voice disorders. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Comprehensive analysis of all triple helical repeats in beta-spectrins reveals patterns of selective evolutionary conservation.

PubMed

Baines, Anthony J

2003-01-01

The spectrin superfamily (spectrin, alpha-actinin, utrophin and dystrophin) has in common a triple helical repeating unit of ~106 amino acid residues. In spectrin, alpha and beta chains contain multiple copies of this repeat. beta-spectrin chains contain the majority of binding activities in spectrin and are essential for animal life. Canonical beta-spectrins have 17 repeats; beta-heavy spectrins have 30. Here, the repeats of five human beta-spectrins, plus beta-spectrins from several other vertebrates and invertebrates, have been analysed. Repeats 1, 2, 14 and 17 in canonical beta are highly conserved between invertebrates and vertebrates, and repeat 8 in some isoforms. This is consistent with conservation of critical functions, since repeats 1, 2 and 17 bind alpha-spectrin. Repeats 1 of beta-spectrins are not always detected by SMART or Pfam tools. A profile hidden Markov model of beta-spectrin repeat 1 detects alpha-actinins, but not utrophin or dystrophin. Novel examples of repeat 1 were detected in the spectraplakins MACF1, BPAG1 and plectin close to the actin-binding domain. Ankyrin binds to the C-terminal portion of repeat 14; the high conservation of this entire repeat may point to additional, undiscovered ligand-binding activities. This analysis indicates that the basic triple helical repeat pattern was adapted early in the evolution of the spectrin superfamily to encompass essential binding activities, which characterise individual repeats in proteins extant today.

Behavioral Vaccines and Evidence Based Kernels: Non-Pharmaceutical Approaches for the Prevention of Mental, Emotional and Behavioral Disorders 1

PubMed Central

Embry, Dennis D.

2011-01-01

In March of 2009, the Institute of Medicine issued a new report on the Prevention of Mental, Emotional and Behavioral Disorders Among Young People.1 Fundamentally, the report calls for ending the rationing of prevention of mental, emotional and behavioral disorders (MEBs) among America’s children, youth and young adults. Continued rationing of access to scientifically proven prevention causes a serious threat to the country’s national security2 and to our economic competitiveness compared to 22 other rich countries.3 Such MEBs are also the leading preventable cost center for local, state and the federal governments.1, 4 These preventable MEBs cause health-care costs to continue to spiral up. The IOM Report calls for a public-health approach to MEBs—basically like how America and Canada dealt with the polio epidemic, measles, mumps, car passenger injuries to children, and accidental poisoning from medications and toxic chemicals. Why is this necessary? America’s rates of some of these mental, emotional and behavioral problems are worse than other developed countries,5, 6 and rates of some of these problems have objectively increased over the past 20-50 years in America.7 The attributes of a public-health approach for MEBs are defined in the article. The article discusses multiple examples of how public health approaches might reduce or prevent MEBs using low-cost evidence based kernels, which are fundamental units of behavior. Such kernels can be used repeatedly, which then act as “behavioral vaccines” to reduce morbidity or mortality and/or improve human wellbeing. This document calls for six key policy actions to improve mental, emotional and behavioral health in young people—with resulting wellbeing and economic competiveness of North America and reducing health-care costs. PMID:21333837

Teaching Three-Dimensional Structural Chemistry Using Crystal Structure Databases. 2. Teaching Units that Utilize an Interactive Web-Accessible Subset of the Cambridge Structural Database

ERIC Educational Resources Information Center

Battle, Gary M.; Allen, Frank H.; Ferrence, Gregory M.

2010-01-01

A series of online interactive teaching units have been developed that illustrate the use of experimentally measured three-dimensional (3D) structures to teach fundamental chemistry concepts. The units integrate a 500-structure subset of the Cambridge Structural Database specially chosen for their pedagogical value. The units span a number of key…

A fundamental review of the relationships between nanotechnology and lignocellulosic biomass

Treesearch

Theodore Wegner; E. Philip Jones

2009-01-01

At first glance, the relationship between nanotechnology and lignocellulosic biomass may seem to be unconnected or at best tenuously connected. It is important to recognize that. at a fundamental level, lignocellulosic biomass is made up of nanometer-size constitutive building block units that provide valuable properties to wood and other types of renewable...

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT XI, INTRODUCTION TO ELECTRICAL MAINTENANCE FOR OFF-HIGHWAY VEHICLES.

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO FAMILIARIZE THE TRAINEE WITH THE FUNDAMENTALS OF ELECTRICITY AND MAGNETISM AS THEY RELATE TO DIESEL POWERED EQUIPMENT. TOPICS ARE (1) FUNDAMENTALS OF ELECTRICITY AND MAGNETISM, (2) ELECTROMAGNETIC FIELDS, (3) MAGNETIC FORCE ON A CONDUCTOR, (4) ELECTROMAGNETIC INDUCTION, (5) OHM'S LAW, (6) METER…

Repeatability and Reproducibility in Proteomic Identifications by Liquid Chromatography—Tandem Mass Spectrometry

PubMed Central

Tabb, David L.; Vega-Montoto, Lorenzo; Rudnick, Paul A.; Variyath, Asokan Mulayath; Ham, Amy-Joan L.; Bunk, David M.; Kilpatrick, Lisa E.; Billheimer, Dean D.; Blackman, Ronald K.; Cardasis, Helene L.; Carr, Steven A.; Clauser, Karl R.; Jaffe, Jacob D.; Kowalski, Kevin A.; Neubert, Thomas A.; Regnier, Fred E.; Schilling, Birgit; Tegeler, Tony J.; Wang, Mu; Wang, Pei; Whiteaker, Jeffrey R.; Zimmerman, Lisa J.; Fisher, Susan J.; Gibson, Bradford W.; Kinsinger, Christopher R.; Mesri, Mehdi; Rodriguez, Henry; Stein, Steven E.; Tempst, Paul; Paulovich, Amanda G.; Liebler, Daniel C.; Spiegelman, Cliff

2009-01-01

The complexity of proteomic instrumentation for LC-MS/MS introduces many possible sources of variability. Data-dependent sampling of peptides constitutes a stochastic element at the heart of discovery proteomics. Although this variation impacts the identification of peptides, proteomic identifications are far from completely random. In this study, we analyzed interlaboratory data sets from the NCI Clinical Proteomic Technology Assessment for Cancer to examine repeatability and reproducibility in peptide and protein identifications. Included data spanned 144 LC-MS/MS experiments on four Thermo LTQ and four Orbitrap instruments. Samples included yeast lysate, the NCI-20 defined dynamic range protein mix, and the Sigma UPS 1 defined equimolar protein mix. Some of our findings reinforced conventional wisdom, such as repeatability and reproducibility being higher for proteins than for peptides. Most lessons from the data, however, were more subtle. Orbitraps proved capable of higher repeatability and reproducibility, but aberrant performance occasionally erased these gains. Even the simplest protein digestions yielded more peptide ions than LC-MS/MS could identify during a single experiment. We observed that peptide lists from pairs of technical replicates overlapped by 35–60%, giving a range for peptide-level repeatability in these experiments. Sample complexity did not appear to affect peptide identification repeatability, even as numbers of identified spectra changed by an order of magnitude. Statistical analysis of protein spectral counts revealed greater stability across technical replicates for Orbitraps, making them superior to LTQ instruments for biomarker candidate discovery. The most repeatable peptides were those corresponding to conventional tryptic cleavage sites, those that produced intense MS signals, and those that resulted from proteins generating many distinct peptides. Reproducibility among different instruments of the same type lagged behind repeatability of technical replicates on a single instrument by several percent. These findings reinforce the importance of evaluating repeatability as a fundamental characteristic of analytical technologies. PMID:19921851

Clinical trial design in the neurocritical care unit.

PubMed

Hall, C E; Mirski, M; Palesch, Y Y; Diringer, M N; Qureshi, A I; Robertson, C S; Geocadin, R; Wijman, C A C; Le Roux, P D; Suarez, Jose I

2012-02-01

Clinical trials provide a robust mechanism to advance science and change clinical practice across the widest possible spectrum. Fundamental in the Neurocritical Care Society's mission is to promote Quality Patient Care by identifying and implementing best medical practices for acute neurological disorders that are consistent with the current scientific knowledge. The next logical step will be to foster rapid growth of our scientific body of evidence, to establish and disseminate these best practices. In this manuscript, five invited experts were impaneled to address questions, identified by the conference organizing committee as fundamental issues for the design of clinical trials in the neurological intensive care unit setting.

Structural analysis of two length variants of the rDNA intergenic spacer from Eruca sativa.

PubMed

Lakshmikumaran, M; Negi, M S

1994-03-01

Restriction enzyme analysis of the rRNA genes of Eruca sativa indicated the presence of many length variants within a single plant and also between different cultivars which is unusual for most crucifers studied so far. Two length variants of the rDNA intergenic spacer (IGS) from a single individual E. sativa (cv. Itsa) plant were cloned and characterized. The complete nucleotide sequences of both the variants (3 kb and 4 kb) were determined. The intergenic spacer contains three families of tandemly repeated DNA sequences denoted as A, B and C. However, the long (4 kb) variant shows the presence of an additional repeat, denoted as D, which is a duplication of a 224 bp sequence just upstream of the putative transcription initiation site. Repeat units belonging to the three different families (A, B and C) were in the size range of 22 to 30 bp. Such short repeat elements are present in the IGS of most of the crucifers analysed so far. Sequence analysis of the variants (3 kb and 4 kb) revealed that the length heterogeneity of the spacer is located at three different regions and is due to the varying copy numbers of repeat units belonging to families A and B. Length variation of the spacer is also due to the presence of a large duplication (D repeats) in the 4 kb variant which is absent in the 3 kb variant. The putative transcription initiation site was identified by comparisons with the rDNA sequences from other plant species.

A new technique for the characterization of chaff elements

NASA Astrophysics Data System (ADS)

Scholfield, David; Myat, Maung; Dauby, Jason; Fesler, Jonathon; Bright, Jonathan

2011-07-01

A new technique for the experimental characterization of electromagnetic chaff based on Inverse Synthetic Aperture Radar is presented. This technique allows for the characterization of as few as one filament of chaff in a controlled anechoic environment allowing for stability and repeatability of experimental results. This approach allows for a deeper understanding of the fundamental phenomena of electromagnetic scattering from chaff through an incremental analysis approach. Chaff analysis can now begin with a single element and progress through the build-up of particles into pseudo-cloud structures. This controlled incremental approach is supported by an identical incremental modeling and validation process. Additionally, this technique has the potential to produce considerable savings in financial and schedule cost and provides a stable and repeatable experiment to aid model valuation.

Fundamental movement skills and children with attention-deficit hyperactivity disorder: peer comparisons and stimulant effects.

PubMed

Harvey, William J; Reid, Greg; Grizenko, Natalie; Mbekou, Valentin; Ter-Stepanian, Marina; Joober, Ridha

2007-10-01

The purpose of this study was to compare the fundamental movement skills of 22 children with attention-deficit hyperactivity disorder (ADHD), from 6 to 12 years of age, to gender- and age-matched peers without ADHD and assess the effects of stimulant medication on the movement skill performance of the children with ADHD. Repeated measures analyses revealed significant skill differences between children with and without ADHD (p

Know Your America: Suggested Study Course in Americanism. Revised Edition.

ERIC Educational Resources Information Center

American Legion, Indianapolis, IN. Americanism and Children's Youth Div.

The purpose of this booklet is to increase understanding of fundamental U.S. documents, the U.S. flag, patriotic institutions, and of San Francisco (California), March 14-16, 1986 of U.S. residents. Unit 2 describes and interprets the code of displaying the U.S. flag and provides a suggested flag education unit of study. Units 3 and 4 offer…

Blending in: The Extent and Promise of Blended Education in the United States

ERIC Educational Resources Information Center

Allen, I. Elaine; Seaman, Jeff; Garrett, Richard

2007-01-01

"Blending In: The Extent and Promise of Blended Education in the United States" builds on the series of annual reports on the state of online education in U.S. Higher Education. This study, like the previous reports, is aimed at answering some of the fundamental questions about the nature and extent of education in the United States.…

Hydraulics.

ERIC Educational Resources Information Center

Decker, Robert L.

Designed for use in courses where students are expected to become proficient in the area of hydraulics, including diesel engine mechanic programs, this curriculum guide is comprised of fourteen units of instruction. Unit titles include (1) Introduction, (2) Fundamentals of Hydraulics, (3) Reservoirs, (4) Lines, Fittings, and Couplers, (5) Seals,…

Development of Electrochemical Supercapacitors for EMA Applications

NASA Technical Reports Server (NTRS)

Kosek, John A.; Dunning, Thomas; LaConti, Anthony B.

1996-01-01

A limitation of the typical electrochemical capacitor is the maximum available power and energy density, and an improvement in capacitance per unit weight and volume is needed. A solid-ionomer electrochemical capacitor having a unit cell capacitance greater than 2 F/sq cm and a repeating element thickness of 6 mils has been developed. This capacitor could provide high-current pulses for electromechanical actuation (EMA). Primary project objectives were to develop high-capacitance particulates, to increase capacitor gravimetric and volumetric energy densities above baseline and to fabricate a 10-V capacitor with a repeating element thickness of 6 mils or less. Specific EMA applications were identified and capacitor weight and volume projections made.

The United States Army’s Full-Spectrum Training Strategy Challenge

DTIC Science & Technology

2012-05-17

the high operational tempo for deployed and deploying units. Soldiers and units conducted repeat deployments to both Iraq and Afghanistan with little...prevalent in Strategic Operational Design and associated variations of design. Further complicating Israeli ideas of warfare was the notion that...Army to develop an overarching operational framework that finally replaces Airland Battle, like EBO or some variation of operational design. But one

Understanding the new HbA1c units for the diagnosis of Type 2 diabetes.

PubMed

Braatvedt, Geoff D; Cundy, Tim; Crooke, Michael; Florkowski, Chris; Mann, Jim I; Lunt, Helen; Jackson, Rod; Orr-Walker, Brandon; Kenealy, Timothy; Drury, Paul L

2012-09-21

In New Zealand laboratories the measurement of glycated haemoglobin (HbA1c) for diagnosis of diabetes is now only reported in SI units of mmol/mol. HbA1c is now recommended as the preferred test to diagnose diabetes in most circumstances. The requirement for a second positive test in asymptomatic individuals is retained. An HbA1c greater than and equal to 50 mmol/mol (repeated on a second occasion in asymptomatic patients) is diagnostic of diabetes and a value less than and equal to 40 mmol/mol represents normal glucose tolerance. For patients with an initial HbA1c result of 41-49 mmol/mol, cardiovascular risk assessment and lifestyle interventions are recommended with repeat HbA1c screening in 6-12 months. For patients whose HbA1c is less than and equal to 40 mmol/mol, repeat screening (including for CVD risk) at intermittent intervals is recommended as per published guidelines.

Translations on Eastern Europe Political, Sociological, and Military Affairs No. 1423.

DTIC Science & Technology

1977-07-26

expected to analyze positive , we repeat positive , exper- iences acquired in the course of the implementation of the principles adopted and agreements...all countries, found a positive response in Europe and elsewhere. However, the communique emphasized at the same time that the facts testify- ing...political affairs and in work and study. The fundamental source of the positive development of the Union of Socialist Youth and of the Union’s Pioneer

Characteristics of the Motor Units during Sternocleidomastoid Isometric Flexion among Patients with Mechanical Neck Disorder and Asymptomatic Individuals.

PubMed

Yang, Chia-Chi; Su, Fong-Chin; Yang, Po-Ching; Lin, Hwai-Ting; Guo, Lan-Yuen

2016-01-01

Mechanical neck disorder is a widespread and non-neurological musculoskeletal condition resulting from modern lifestyles. Presently, the fundamental electrophysiological properties of the motor units of the sternocleidomastoid muscles and the characteristics of the short-term synchronization of the motor unit in patients with neck pain are ambiguous. This study therefore aims to clarify the fundamental electrophysiological properties of the motor units of the sternocleidomastoid muscles in patients with mechanical neck disorder and in asymptomatic individuals. We further investigated whether alterations in the degree of motor unit short-term synchronization occur. The surface electrophysiological signals of the bilateral sternal heads of the sternocleidomastoid muscles of twelve patients with mechanical neck disorder and asymptomatic individuals were detected at 25% of the maximum voluntary contraction during cervical isometric flexion and then decomposed into individual motor unit action potential trains. We found that the patients with mechanical neck disorder showed significantly higher initial and mean firing rates of the sternocleidomastoid muscles and displayed substantially lower motor unit short-term synchronization values compared with the asymptomatic subjects. Consequently, these convincing findings support the assertion that patients with mechanical neck disorder display altered neuromuscular control strategies, such as the reinforcement of motor unit recruitment firing rates in the sternocleidomastoid muscles. The motor units of these patients also revealed neural recruitment strategies with relatively poor efficiency when executing the required motor tasks.

Characteristics of the Motor Units during Sternocleidomastoid Isometric Flexion among Patients with Mechanical Neck Disorder and Asymptomatic Individuals

PubMed Central

Yang, Chia-Chi; Su, Fong-Chin; Yang, Po-Ching; Lin, Hwai-Ting

2016-01-01

Mechanical neck disorder is a widespread and non-neurological musculoskeletal condition resulting from modern lifestyles. Presently, the fundamental electrophysiological properties of the motor units of the sternocleidomastoid muscles and the characteristics of the short-term synchronization of the motor unit in patients with neck pain are ambiguous. This study therefore aims to clarify the fundamental electrophysiological properties of the motor units of the sternocleidomastoid muscles in patients with mechanical neck disorder and in asymptomatic individuals. We further investigated whether alterations in the degree of motor unit short-term synchronization occur. The surface electrophysiological signals of the bilateral sternal heads of the sternocleidomastoid muscles of twelve patients with mechanical neck disorder and asymptomatic individuals were detected at 25% of the maximum voluntary contraction during cervical isometric flexion and then decomposed into individual motor unit action potential trains. We found that the patients with mechanical neck disorder showed significantly higher initial and mean firing rates of the sternocleidomastoid muscles and displayed substantially lower motor unit short-term synchronization values compared with the asymptomatic subjects. Consequently, these convincing findings support the assertion that patients with mechanical neck disorder display altered neuromuscular control strategies, such as the reinforcement of motor unit recruitment firing rates in the sternocleidomastoid muscles. The motor units of these patients also revealed neural recruitment strategies with relatively poor efficiency when executing the required motor tasks. PMID:27941995

CAG repeat expansion in Huntington disease determines age at onset in a fully dominant fashion

PubMed Central

Lee, J.-M.; Ramos, E.M.; Lee, J.-H.; Gillis, T.; Mysore, J.S.; Hayden, M.R.; Warby, S.C.; Morrison, P.; Nance, M.; Ross, C.A.; Margolis, R.L.; Squitieri, F.; Orobello, S.; Di Donato, S.; Gomez-Tortosa, E.; Ayuso, C.; Suchowersky, O.; Trent, R.J.A.; McCusker, E.; Novelletto, A.; Frontali, M.; Jones, R.; Ashizawa, T.; Frank, S.; Saint-Hilaire, M.H.; Hersch, S.M.; Rosas, H.D.; Lucente, D.; Harrison, M.B.; Zanko, A.; Abramson, R.K.; Marder, K.; Sequeiros, J.; Paulsen, J.S.; Landwehrmeyer, G.B.; Myers, R.H.; MacDonald, M.E.; Durr, Alexandra; Rosenblatt, Adam; Frati, Luigi; Perlman, Susan; Conneally, Patrick M.; Klimek, Mary Lou; Diggin, Melissa; Hadzi, Tiffany; Duckett, Ayana; Ahmed, Anwar; Allen, Paul; Ames, David; Anderson, Christine; Anderson, Karla; Anderson, Karen; Andrews, Thomasin; Ashburner, John; Axelson, Eric; Aylward, Elizabeth; Barker, Roger A.; Barth, Katrin; Barton, Stacey; Baynes, Kathleen; Bea, Alexandra; Beall, Erik; Beg, Mirza Faisal; Beglinger, Leigh J.; Biglan, Kevin; Bjork, Kristine; Blanchard, Steve; Bockholt, Jeremy; Bommu, Sudharshan Reddy; Brossman, Bradley; Burrows, Maggie; Calhoun, Vince; Carlozzi, Noelle; Chesire, Amy; Chiu, Edmond; Chua, Phyllis; Connell, R.J.; Connor, Carmela; Corey-Bloom, Jody; Craufurd, David; Cross, Stephen; Cysique, Lucette; Santos, Rachelle Dar; Davis, Jennifer; Decolongon, Joji; DiPietro, Anna; Doucette, Nicholas; Downing, Nancy; Dudler, Ann; Dunn, Steve; Ecker, Daniel; Epping, Eric A.; Erickson, Diane; Erwin, Cheryl; Evans, Ken; Factor, Stewart A.; Farias, Sarah; Fatas, Marta; Fiedorowicz, Jess; Fullam, Ruth; Furtado, Sarah; Garde, Monica Bascunana; Gehl, Carissa; Geschwind, Michael D.; Goh, Anita; Gooblar, Jon; Goodman, Anna; Griffith, Jane; Groves, Mark; Guttman, Mark; Hamilton, Joanne; Harrington, Deborah; Harris, Greg; Heaton, Robert K.; Helmer, Karl; Henneberry, Machelle; Hershey, Tamara; Herwig, Kelly; Howard, Elizabeth; Hunter, Christine; Jankovic, Joseph; Johnson, Hans; Johnson, Arik; Jones, Kathy; Juhl, Andrew; Kim, Eun Young; Kimble, Mycah; King, Pamela; Klimek, Mary Lou; Klöppel, Stefan; Koenig, Katherine; Komiti, Angela; Kumar, Rajeev; Langbehn, Douglas; Leavitt, Blair; Leserman, Anne; Lim, Kelvin; Lipe, Hillary; Lowe, Mark; Magnotta, Vincent A.; Mallonee, William M.; Mans, Nicole; Marietta, Jacquie; Marshall, Frederick; Martin, Wayne; Mason, Sarah; Matheson, Kirsty; Matson, Wayne; Mazzoni, Pietro; McDowell, William; Miedzybrodzka, Zosia; Miller, Michael; Mills, James; Miracle, Dawn; Montross, Kelsey; Moore, David; Mori, Sasumu; Moser, David J.; Moskowitz, Carol; Newman, Emily; Nopoulos, Peg; Novak, Marianne; O'Rourke, Justin; Oakes, David; Ondo, William; Orth, Michael; Panegyres, Peter; Pease, Karen; Perlman, Susan; Perlmutter, Joel; Peterson, Asa; Phillips, Michael; Pierson, Ron; Potkin, Steve; Preston, Joy; Quaid, Kimberly; Radtke, Dawn; Rae, Daniela; Rao, Stephen; Raymond, Lynn; Reading, Sarah; Ready, Rebecca; Reece, Christine; Reilmann, Ralf; Reynolds, Norm; Richardson, Kylie; Rickards, Hugh; Ro, Eunyoe; Robinson, Robert; Rodnitzky, Robert; Rogers, Ben; Rosenblatt, Adam; Rosser, Elisabeth; Rosser, Anne; Price, Kathy; Price, Kathy; Ryan, Pat; Salmon, David; Samii, Ali; Schumacher, Jamy; Schumacher, Jessica; Sendon, Jose Luis Lópenz; Shear, Paula; Sheinberg, Alanna; Shpritz, Barnett; Siedlecki, Karen; Simpson, Sheila A.; Singer, Adam; Smith, Jim; Smith, Megan; Smith, Glenn; Snyder, Pete; Song, Allen; Sran, Satwinder; Stephan, Klaas; Stober, Janice; Sü?muth, Sigurd; Suter, Greg; Tabrizi, Sarah; Tempkin, Terry; Testa, Claudia; Thompson, Sean; Thomsen, Teri; Thumma, Kelli; Toga, Arthur; Trautmann, Sonja; Tremont, Geoff; Turner, Jessica; Uc, Ergun; Vaccarino, Anthony; van Duijn, Eric; Van Walsem, Marleen; Vik, Stacie; Vonsattel, Jean Paul; Vuletich, Elizabeth; Warner, Tom; Wasserman, Paula; Wassink, Thomas; Waterman, Elijah; Weaver, Kurt; Weir, David; Welsh, Claire; Werling-Witkoske, Chris; Wesson, Melissa; Westervelt, Holly; Weydt, Patrick; Wheelock, Vicki; Williams, Kent; Williams, Janet; Wodarski, Mary; Wojcieszek, Joanne; Wood, Jessica; Wood-Siverio, Cathy; Wu, Shuhua; Yastrubetskaya, Olga; de Yebenes, Justo Garcia; Zhao, Yong Qiang; Zimbelman, Janice; Zschiegner, Roland; Aaserud, Olaf; Abbruzzese, Giovanni; Andrews, Thomasin; Andrich, Jurgin; Antczak, Jakub; Arran, Natalie; Artiga, Maria J. Saiz; Bachoud-Lévi, Anne-Catherine; Banaszkiewicz, Krysztof; di Poggio, Monica Bandettini; Bandmann, Oliver; Barbera, Miguel A.; Barker, Roger A.; Barrero, Francisco; Barth, Katrin; Bas, Jordi; Beister, Antoine; Bentivoglio, Anna Rita; Bertini, Elisabetta; Biunno, Ida; Bjørgo, Kathrine; Bjørnevoll, Inga; Bohlen, Stefan; Bonelli, Raphael M.; Bos, Reineke; Bourne, Colin; Bradbury, Alyson; Brockie, Peter; Brown, Felicity; Bruno, Stefania; Bryl, Anna; Buck, Andrea; Burg, Sabrina; Burgunder, Jean-Marc; Burns, Peter; Burrows, Liz; Busquets, Nuria; Busse, Monica; Calopa, Matilde; Carruesco, Gemma T.; Casado, Ana Gonzalez; Catena, Judit López; Chu, Carol; Ciesielska, Anna; Clapton, Jackie; Clayton, Carole; Clenaghan, Catherine; Coelho, Miguel; Connemann, Julia; Craufurd, David; Crooks, Jenny; Cubillo, Patricia Trigo; Cubo, Esther; Curtis, Adrienne; De Michele, Giuseppe; De Nicola, A.; de Souza, Jenny; de Weert, A. Marit; de Yébenes, Justo Garcia; Dekker, M.; Descals, A. Martínez; Di Maio, Luigi; Di Pietro, Anna; Dipple, Heather; Dose, Matthias; Dumas, Eve M.; Dunnett, Stephen; Ecker, Daniel; Elifani, F.; Ellison-Rose, Lynda; Elorza, Marina D.; Eschenbach, Carolin; Evans, Carole; Fairtlough, Helen; Fannemel, Madelein; Fasano, Alfonso; Fenollar, Maria; Ferrandes, Giovanna; Ferreira, Jaoquim J.; Fillingham, Kay; Finisterra, Ana Maria; Fisher, K.; Fletcher, Amy; Foster, Jillian; Foustanos, Isabella; Frech, Fernando A.; Fullam, Robert; Fullham, Ruth; Gago, Miguel; García, RocioGarcía-Ramos; García, Socorro S.; Garrett, Carolina; Gellera, Cinzia; Gill, Paul; Ginestroni, Andrea; Golding, Charlotte; Goodman, Anna; Gørvell, Per; Grant, Janet; Griguoli, A.; Gross, Diana; Guedes, Leonor; BascuñanaGuerra, Monica; Guerra, Maria Rosalia; Guerrero, Rosa; Guia, Dolores B.; Guidubaldi, Arianna; Hallam, Caroline; Hamer, Stephanie; Hammer, Kathrin; Handley, Olivia J.; Harding, Alison; Hasholt, Lis; Hedge, Reikha; Heiberg, Arvid; Heinicke, Walburgis; Held, Christine; Hernanz, Laura Casas; Herranhof, Briggitte; Herrera, Carmen Durán; Hidding, Ute; Hiivola, Heli; Hill, Susan; Hjermind, Lena. E.; Hobson, Emma; Hoffmann, Rainer; Holl, Anna Hödl; Howard, Liz; Hunt, Sarah; Huson, Susan; Ialongo, Tamara; Idiago, Jesus Miguel R.; Illmann, Torsten; Jachinska, Katarzyna; Jacopini, Gioia; Jakobsen, Oda; Jamieson, Stuart; Jamrozik, Zygmunt; Janik, Piotr; Johns, Nicola; Jones, Lesley; Jones, Una; Jurgens, Caroline K.; Kaelin, Alain; Kalbarczyk, Anna; Kershaw, Ann; Khalil, Hanan; Kieni, Janina; Klimberg, Aneta; Koivisto, Susana P.; Koppers, Kerstin; Kosinski, Christoph Michael; Krawczyk, Malgorzata; Kremer, Berry; Krysa, Wioletta; Kwiecinski, Hubert; Lahiri, Nayana; Lambeck, Johann; Lange, Herwig; Laver, Fiona; Leenders, K.L.; Levey, Jamie; Leythaeuser, Gabriele; Lezius, Franziska; Llesoy, Joan Roig; Löhle, Matthias; López, Cristobal Diez-Aja; Lorenza, Fortuna; Loria, Giovanna; Magnet, Markus; Mandich, Paola; Marchese, Roberta; Marcinkowski, Jerzy; Mariotti, Caterina; Mariscal, Natividad; Markova, Ivana; Marquard, Ralf; Martikainen, Kirsti; Martínez, Isabel Haro; Martínez-Descals, Asuncion; Martino, T.; Mason, Sarah; McKenzie, Sue; Mechi, Claudia; Mendes, Tiago; Mestre, Tiago; Middleton, Julia; Milkereit, Eva; Miller, Joanne; Miller, Julie; Minster, Sara; Möller, Jens Carsten; Monza, Daniela; Morales, Blas; Moreau, Laura V.; Moreno, Jose L. López-Sendón; Münchau, Alexander; Murch, Ann; Nielsen, Jørgen E.; Niess, Anke; Nørremølle, Anne; Novak, Marianne; O'Donovan, Kristy; Orth, Michael; Otti, Daniela; Owen, Michael; Padieu, Helene; Paganini, Marco; Painold, Annamaria; Päivärinta, Markku; Partington-Jones, Lucy; Paterski, Laurent; Paterson, Nicole; Patino, Dawn; Patton, Michael; Peinemann, Alexander; Peppa, Nadia; Perea, Maria Fuensanta Noguera; Peterson, Maria; Piacentini, Silvia; Piano, Carla; Càrdenas, Regina Pons i; Prehn, Christian; Price, Kathleen; Probst, Daniela; Quarrell, Oliver; Quiroga, Purificacion Pin; Raab, Tina; Rakowicz, Maryla; Raman, Ashok; Raymond, Lucy; Reilmann, Ralf; Reinante, Gema; Reisinger, Karin; Retterstol, Lars; Ribaï, Pascale; Riballo, Antonio V.; Ribas, Guillermo G.; Richter, Sven; Rickards, Hugh; Rinaldi, Carlo; Rissling, Ida; Ritchie, Stuart; Rivera, Susana Vázquez; Robert, Misericordia Floriach; Roca, Elvira; Romano, Silvia; Romoli, Anna Maria; Roos, Raymond A.C.; Røren, Niini; Rose, Sarah; Rosser, Elisabeth; Rosser, Anne; Rossi, Fabiana; Rothery, Jean; Rudzinska, Monika; Ruíz, Pedro J. García; Ruíz, Belan Garzon; Russo, Cinzia Valeria; Ryglewicz, Danuta; Saft, Carston; Salvatore, Elena; Sánchez, Vicenta; Sando, Sigrid Botne; Šašinková, Pavla; Sass, Christian; Scheibl, Monika; Schiefer, Johannes; Schlangen, Christiane; Schmidt, Simone; Schöggl, Helmut; Schrenk, Caroline; Schüpbach, Michael; Schuierer, Michele; Sebastián, Ana Rojo; Selimbegovic-Turkovic, Amina; Sempolowicz, Justyna; Silva, Mark; Sitek, Emilia; Slawek, Jaroslaw; Snowden, Julie; Soleti, Francesco; Soliveri, Paola; Sollom, Andrea; Soltan, Witold; Sorbi, Sandro; Sorensen, Sven Asger; Spadaro, Maria; Städtler, Michael; Stamm, Christiane; Steiner, Tanja; Stokholm, Jette; Stokke, Bodil; Stopford, Cheryl; Storch, Alexander; Straßburger, Katrin; Stubbe, Lars; Sulek, Anna; Szczudlik, Andrzej; Tabrizi, Sarah; Taylor, Rachel; Terol, Santiago Duran-Sindreu; Thomas, Gareth; Thompson, Jennifer; Thomson, Aileen; Tidswell, Katherine; Torres, Maria M. Antequera; Toscano, Jean; Townhill, Jenny; Trautmann, Sonja; Tucci, Tecla; Tuuha, Katri; Uhrova, Tereza; Valadas, Anabela; van Hout, Monique S.E.; van Oostrom, J.C.H.; van Vugt, Jeroen P.P.; vanm, Walsem Marleen R.; Vandenberghe, Wim; Verellen-Dumoulin, Christine; Vergara, Mar Ruiz; Verstappen, C.C.P.; Verstraelen, Nichola; Viladrich, Celia Mareca; Villanueva, Clara; Wahlström, Jan; Warner, Thomas; Wehus, Raghild; Weindl, Adolf; Werner, Cornelius J.; Westmoreland, Leann; Weydt, Patrick; Wiedemann, Alexandra; Wild, Edward; Wild, Sue; Witjes-Ané, Marie-Noelle; Witkowski, Grzegorz; Wójcik, Magdalena; Wolz, Martin; Wolz, Annett; Wright, Jan; Yardumian, Pam; Yates, Shona; Yudina, Elizaveta; Zaremba, Jacek; Zaugg, Sabine W.; Zdzienicka, Elzbieta; Zielonka, Daniel; Zielonka, Euginiusz; Zinzi, Paola; Zittel, Simone; Zucker, Birgrit; Adams, John; Agarwal, Pinky; Antonijevic, Irina; Beck, Christopher; Chiu, Edmond; Churchyard, Andrew; Colcher, Amy; Corey-Bloom, Jody; Dorsey, Ray; Drazinic, Carolyn; Dubinsky, Richard; Duff, Kevin; Factor, Stewart; Foroud, Tatiana; Furtado, Sarah; Giuliano, Joe; Greenamyre, Timothy; Higgins, Don; Jankovic, Joseph; Jennings, Dana; Kang, Un Jung; Kostyk, Sandra; Kumar, Rajeev; Leavitt, Blair; LeDoux, Mark; Mallonee, William; Marshall, Frederick; Mohlo, Eric; Morgan, John; Oakes, David; Panegyres, Peter; Panisset, Michel; Perlman, Susan; Perlmutter, Joel; Quaid, Kimberly; Raymond, Lynn; Revilla, Fredy; Robertson, Suzanne; Robottom, Bradley; Sanchez-Ramos, Juan; Scott, Burton; Shannon, Kathleen; Shoulson, Ira; Singer, Carlos; Tabbal, Samer; Testa, Claudia; van, Kammen Dan; Vetter, Louise; Walker, Francis; Warner, John; Weiner, illiam; Wheelock, Vicki; Yastrubetskaya, Olga; Barton, Stacey; Broyles, Janice; Clouse, Ronda; Coleman, Allison; Davis, Robert; Decolongon, Joji; DeLaRosa, Jeanene; Deuel, Lisa; Dietrich, Susan; Dubinsky, Hilary; Eaton, Ken; Erickson, Diane; Fitzpatrick, Mary Jane; Frucht, Steven; Gartner, Maureen; Goldstein, Jody; Griffith, Jane; Hickey, Charlyne; Hunt, Victoria; Jaglin, Jeana; Klimek, Mary Lou; Lindsay, Pat; Louis, Elan; Loy, Clemet; Lucarelli, Nancy; Malarick, Keith; Martin, Amanda; McInnis, Robert; Moskowitz, Carol; Muratori, Lisa; Nucifora, Frederick; O'Neill, Christine; Palao, Alicia; Peavy, Guerry; Quesada, Monica; Schmidt, Amy; Segro, Vicki; Sperin, Elaine; Suter, Greg; Tanev, Kalo; Tempkin, Teresa; Thiede, Curtis; Wasserman, Paula; Welsh, Claire; Wesson, Melissa; Zauber, Elizabeth

2012-01-01

Objective: Age at onset of diagnostic motor manifestations in Huntington disease (HD) is strongly correlated with an expanded CAG trinucleotide repeat. The length of the normal CAG repeat allele has been reported also to influence age at onset, in interaction with the expanded allele. Due to profound implications for disease mechanism and modification, we tested whether the normal allele, interaction between the expanded and normal alleles, or presence of a second expanded allele affects age at onset of HD motor signs. Methods: We modeled natural log-transformed age at onset as a function of CAG repeat lengths of expanded and normal alleles and their interaction by linear regression. Results: An apparently significant effect of interaction on age at motor onset among 4,068 subjects was dependent on a single outlier data point. A rigorous statistical analysis with a well-behaved dataset that conformed to the fundamental assumptions of linear regression (e.g., constant variance and normally distributed error) revealed significance only for the expanded CAG repeat, with no effect of the normal CAG repeat. Ten subjects with 2 expanded alleles showed an age at motor onset consistent with the length of the larger expanded allele. Conclusions: Normal allele CAG length, interaction between expanded and normal alleles, and presence of a second expanded allele do not influence age at onset of motor manifestations, indicating that the rate of HD pathogenesis leading to motor diagnosis is determined by a completely dominant action of the longest expanded allele and as yet unidentified genetic or environmental factors. Neurology® 2012;78:690–695 PMID:22323755

Response of soricid populations to repeated fire and fuel reduction treatments in the southern Appalachain Mountains

Treesearch

Charlotte E Matthews; Christopher E Moorman; Cathryn H Greenberg

2009-01-01

Fuel hazards have increased in forests across the United States because offire exclusion during the 20th century. Treatments used to reduce fuel buildup Illay affect wildlife. such as shrews. living 011 the forest floor. especially when treatments are applied repeatedly. From mid-May to mid-August 2006 and 2007.  we used drift fences...

Certificates Count: An Analysis of Sub-Baccalaureate Certificates

ERIC Educational Resources Information Center

Bosworth, Brian

2010-01-01

Since President Obama took office, he has repeatedly called for the United States to significantly improve its postsecondary education performance. One goal in particular has gained wide attention: the President's declaration that in an ever more competitive global marketplace, the United States must once again lead the world in college…

SI units.

PubMed

Lehmann, H P

1979-01-01

The development of the International System of Units (Systeme International d'Unites--SE Units), based on seven fundamental quantities--length, mass, time, electric current, thermodynamic temperature, luminous intensity, and amount of substance is described. Units (coherent and noncoherent) for other measurable quantities that are derived from the seven basic quantities are reviewed. The rationale for the use of SE units in medicine, primarily as applied to clinical laboratory data, is discussed, and arguments are presented for the rigid adoption of SI units in medicine and for exceptions. Tables are given for the basic and derived SI units used in medicine and for conversion factors from the quantities and units in current use to those in SI units.

Repeats of base oligomers as the primordial coding sequences of the primeval earth and their vestiges in modern genes.

PubMed

Ohno, S

1984-01-01

Three outstanding properties uniquely qualify repeats of base oligomers as the primordial coding sequences of all polypeptide chains. First, when compared with randomly generated base sequences in general, they are more likely to have long open reading frames. Second, periodical polypeptide chains specified by such repeats are more likely to assume either alpha-helical or beta-sheet secondary structures than are polypeptide chains of random sequence. Third, provided that the number of bases in the oligomeric unit is not a multiple of 3, these internally repetitious coding sequences are impervious to randomly sustained base substitutions, deletions, and insertions. This is because the recurring periodicity of their polypeptide chains is given by three consecutive copies of the oligomeric unit translated in three different reading frames. Accordingly, when one reading frame is open, the other two are automatically open as well, all three being capable of coding for polypeptide chains of identical periodicity. Under this circumstance, a frame shift due to the deletion or insertion of a number of bases that is not a multiple of 3 fails to alter the down-stream amino acid sequence, and even a base change causing premature chain-termination can silence only one of the three potential coding units. Newly arisen coding sequences in modern organisms are oligomeric repeats, and most of the older genes retain various vestiges of their original internal repetitions. Some of the genes (e.g., oncogenes) have even inherited the property of being impervious to randomly sustained base changes.

SSRscanner: a program for reporting distribution and exact location of simple sequence repeats.

PubMed

Anwar, Tamanna; Khan, Asad U

2006-02-20

Simple sequence repeats (SSRs) have become important molecular markers for a broad range of applications, such as genome mapping and characterization, phenotype mapping, marker assisted selection of crop plants and a range of molecular ecology and diversity studies. These repeated DNA sequences are found in both prokaryotes and eukaryotes. They are distributed almost at random throughout the genome, ranging from mononucleotide to trinucleotide repeats. They are also found at longer lengths (> 6 repeating units) of tracts. Most of the computer programs that find SSRs do not report its exact position. A computer program SSRscanner was written to find out distribution, frequency and exact location of each SSR in the genome. SSRscanner is user friendly. It can search repeats of any length and produce outputs with their exact position on chromosome and their frequency of occurrence in the sequence. This program has been written in PERL and is freely available for non-commercial users by request from the authors. Please contact the authors by E-mail: huzzi99@hotmail.com.

Single-Chain Folding of Synthetic Polymers: A Critical Update.

PubMed

Altintas, Ozcan; Barner-Kowollik, Christopher

2015-11-23

The current contribution serves as a critical update to a previous feature article from us (Macromol. Rapid Commun. 2012, 33, 958-971), and highlights the latest advances in the preparation of single chain polymeric nanoparticles and initial-yet promising-attempts towards mimicking the structure of natural biomacromolecules via single-chain folding of well-defined linear polymers via so-called single chain selective point folding and repeat unit folding. The contribution covers selected examples from the literature published up to ca. September 2015. Our aim is not to provide an exhaustive review but rather highlight a selection of new and exciting examples for single-chain folding based on advanced macromolecular precision chemistry. Initially, the discussion focuses on the synthesis and characterization of single-chain folded structures via selective point folding. The second part of the feature article addresses the folding of well-defined single-chain polymers by means of repeat unit folding. The current state of the art in the field of single-chain folding indicates that repeat unit folding-driven nanoparticle preparation is well-advanced, while initial encouraging steps towards building selective point folding systems have been taken. In addition, a summary of the-in our view-open key questions is provided that may guide future biomimetic design efforts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

History and progress on accurate measurements of the Planck constant.

PubMed

Steiner, Richard

2013-01-01

The measurement of the Planck constant, h, is entering a new phase. The CODATA 2010 recommended value is 6.626 069 57 × 10(-34) J s, but it has been a long road, and the trip is not over yet. Since its discovery as a fundamental physical constant to explain various effects in quantum theory, h has become especially important in defining standards for electrical measurements and soon, for mass determination. Measuring h in the International System of Units (SI) started as experimental attempts merely to prove its existence. Many decades passed while newer experiments measured physical effects that were the influence of h combined with other physical constants: elementary charge, e, and the Avogadro constant, N(A). As experimental techniques improved, the precision of the value of h expanded. When the Josephson and quantum Hall theories led to new electronic devices, and a hundred year old experiment, the absolute ampere, was altered into a watt balance, h not only became vital in definitions for the volt and ohm units, but suddenly it could be measured directly and even more accurately. Finally, as measurement uncertainties now approach a few parts in 10(8) from the watt balance experiments and Avogadro determinations, its importance has been linked to a proposed redefinition of a kilogram unit of mass. The path to higher accuracy in measuring the value of h was not always an example of continuous progress. Since new measurements periodically led to changes in its accepted value and the corresponding SI units, it is helpful to see why there were bumps in the road and where the different branch lines of research joined in the effort. Recalling the bumps along this road will hopefully avoid their repetition in the upcoming SI redefinition debates. This paper begins with a brief history of the methods to measure a combination of fundamental constants, thus indirectly obtaining the Planck constant. The historical path is followed in the section describing how the improved techniques and discoveries in quantum mechanics steadily reduced the uncertainty of h. The central part of this review describes the technical details of the watt balance technique, which is a combination of the mechanical and electronic measurements that now determine h as a direct result, i.e. not requiring measured values of additional fundamental constants. The first technical section describes the basics and some of the common details of many watt balance designs. Next is a review of the ongoing advances at the (currently) seven national metrology institutions where these experiments are pursued. A final summary of the recent h determinations of the last two decades shows how history keeps repeating itself; there is again a question of whether there is a shift in the newest results, albeit at uncertainties that are many orders of magnitude less than the original experiments. The conclusion is that there is room for further development to resolve these differences and find new ideas for a watt balance system with a more universal application. Since the next generation of watt balance experiments are expected to become kilogram realization standards, the historical record suggests that there is yet a need for proof that Planck constant results are finally reproducible at an acceptable uncertainty.

History and progress on accurate measurements of the Planck constant

NASA Astrophysics Data System (ADS)

Steiner, Richard

2013-01-01

The measurement of the Planck constant, h, is entering a new phase. The CODATA 2010 recommended value is 6.626 069 57 × 10-34 J s, but it has been a long road, and the trip is not over yet. Since its discovery as a fundamental physical constant to explain various effects in quantum theory, h has become especially important in defining standards for electrical measurements and soon, for mass determination. Measuring h in the International System of Units (SI) started as experimental attempts merely to prove its existence. Many decades passed while newer experiments measured physical effects that were the influence of h combined with other physical constants: elementary charge, e, and the Avogadro constant, NA. As experimental techniques improved, the precision of the value of h expanded. When the Josephson and quantum Hall theories led to new electronic devices, and a hundred year old experiment, the absolute ampere, was altered into a watt balance, h not only became vital in definitions for the volt and ohm units, but suddenly it could be measured directly and even more accurately. Finally, as measurement uncertainties now approach a few parts in 108 from the watt balance experiments and Avogadro determinations, its importance has been linked to a proposed redefinition of a kilogram unit of mass. The path to higher accuracy in measuring the value of h was not always an example of continuous progress. Since new measurements periodically led to changes in its accepted value and the corresponding SI units, it is helpful to see why there were bumps in the road and where the different branch lines of research joined in the effort. Recalling the bumps along this road will hopefully avoid their repetition in the upcoming SI redefinition debates. This paper begins with a brief history of the methods to measure a combination of fundamental constants, thus indirectly obtaining the Planck constant. The historical path is followed in the section describing how the improved techniques and discoveries in quantum mechanics steadily reduced the uncertainty of h. The central part of this review describes the technical details of the watt balance technique, which is a combination of the mechanical and electronic measurements that now determine h as a direct result, i.e. not requiring measured values of additional fundamental constants. The first technical section describes the basics and some of the common details of many watt balance designs. Next is a review of the ongoing advances at the (currently) seven national metrology institutions where these experiments are pursued. A final summary of the recent h determinations of the last two decades shows how history keeps repeating itself; there is again a question of whether there is a shift in the newest results, albeit at uncertainties that are many orders of magnitude less than the original experiments. The conclusion is that there is room for further development to resolve these differences and find new ideas for a watt balance system with a more universal application. Since the next generation of watt balance experiments are expected to become kilogram realization standards, the historical record suggests that there is yet a need for proof that Planck constant results are finally reproducible at an acceptable uncertainty.

Fine typing of methicillin-resistant Staphylococcus aureus isolates using direct repeat unit and staphylococcal interspersed repeat unit typing methods.

PubMed

Ho, Cheng-Mao; Ho, Mao-Wang; Li, Chi-Yuan; Lu, Jang-Jih

2015-08-01

Methicillin-resistant Staphylococcus aureus (MRSA) typing is an important epidemiologic tool for monitoring trends and preventing outbreaks. However, the efficiency of various MRSA typing methods for each SCCmec MRSA isolate is rarely evaluated. A total of 157 MRSA isolates from four different regions in Taiwan were typed with five different molecular methods, including SCCmec typing, multilocus sequence typing (MLST), spa typing, mec-associated direct repeat unit (dru) copy number determination, and staphylococcal interspersed repeat unit (SIRU) profiling. There were four SCCmec types, eight MLST types, 15 spa types, 11 dru types, and 31 SIRU profiles. The most common type determined by each molecular typing method was SCCmec III (115 isolates, 73.2%), ST239 (99 isolates, 63.1%), t037 (107 isolates, 68.2%), 14 dru copies (76 isolates, 48.4%), and SIRU profile 3013722 (102 isolates, 65%), respectively. When using the combination of MLST, spa typing, and dru copy number, ST5-t002-4 (n = 8), ST239-t037-14 (n = 68), ST59-t437-9 (n = 9), and ST59-t437-11 (n = 6) were found to be the most common types of SCCmec types II (n = 9), III (n = 115), IV (n = 21), and VT (n = 11) isolates, respectively. SCCmec type III isolates were further classified into 11 dru types. Of the 21 SCCmec type IV isolates, 14 SIRU profiles were found. Seven SIRU patterns were observed in the 11 SCCmec type VT isolates. Different typing methods showed a similar Hunter-Gaston discrimination index among the 157 MRSA isolates. However, dru and SIRU typing methods had a better discriminatory power for SCCmec type III and SCCmec types IV and VT isolates, respectively, suggesting that dru and SIRU can be used to further type these isolates. Copyright © 2013. Published by Elsevier B.V.

Genetic Transfer of Salmonella typhimurium and Escherichia coli Lipopolysaccharide Antigens to Escherichia coli K-12

PubMed Central

Jones, Randall T.; Koeltzow, Donald E.; Stocker, B. A. D.

1972-01-01

Escherichia coli K-12 ϰ971 was crossed with a smooth Salmonella typhimurium donor, HfrK6, which transfers early the ilv-linked rfa region determining lipopolysaccharide (LPS) core structure. Two ilv+ hybrids differing in their response to the LPS-specific phages FO and C21 were then crossed with S. typhimurium HfrK9, which transfers early the rfb gene cluster determining O repeat unit structure. Most recombinants selected for his+ (near rfb) were agglutinated by Salmonella factor 4 antiserum. Transfer of an F′ factor (FS400) carrying the rfb–his region of S. typhimurium to the same two ilv+ hybrids gave similar results. LPS extracted from two ilv+,his+, factor 4-positive hybrids contained abequose, the immunodominant sugar for factor 4 specificity. By contrast, his+ hybrids obtained from ϰ971 itself by similar HfrK9 and F′FS400 crosses were not agglutinated by factor 4 antiserum, indicating that the parental E. coli ϰ971 does not have the capacity to attach Salmonella O repeat units to its LPS core. It is concluded that the Salmonella rfb genes are expressed only in E. coli ϰ971 hybrids which have also acquired ilv-linked genes (presumably rfa genes affecting core structure or O-translocase ability, or both) from a S. typhimurium donor. When E. coli ϰ971 was crossed with a smooth E. coli donor, Hfr59, of serotype O8, which transfers his early, most his+ recombinants were agglutinated by E. coli O8 antiserum and lysed by the O8-specific phage, Ω8. This suggests that, although the parental E. coli K-12 strain ϰ971 cannot attach Salmonella-specific repeat units to its LPS core, it does have the capacity to attach E. coli O8-specific repeat units. PMID:4559827

The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior.

PubMed

Baslow, Morris H

2011-01-01

The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological "operating system", a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of "neuronal words and languages" for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic-synaptic-dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA-NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function.

Strongly gliding harmonic tremor during the 2009 eruption of Redoubt Volcano

USGS Publications Warehouse

Hotovec, Alicia J.; Prejean, Stephanie G.; Vidale, John E.; Gomberg, Joan S.

2013-01-01

During the 2009 eruption of Redoubt Volcano, Alaska, gliding harmonic tremor occurred prominently before six nearly consecutive explosions during the second half of the eruptive sequence. The fundamental frequency repeatedly glided upward from < 1 Hz to as high as 30 Hz in less than 10 min, followed by a relative seismic quiescence of 10 to 60 s immediately prior to explosion. High frequency (5 to 20 Hz) gliding returned during the extrusive phase, and lasted for 20 min to 3 h at a time. Although harmonic tremor is not uncommon at volcanoes, tremor at such high frequencies is a rare observation. These frequencies approach or exceed the plausible upper limits of many models that have been suggested for volcanic tremor. We also analyzed the behavior of a swarm of repeating earthquakes that immediately preceded the first instance of pre-explosion gliding harmonic tremor. We find that these earthquakes share several traits with upward gliding harmonic tremor, and favor the explanation that the gliding harmonic tremor at Redoubt Volcano is created by the superposition of increasingly frequent and regular, repeating stick–slip earthquakes through the Dirac comb effect.

Compulsion in family planning: the fundamental considerations.

PubMed

Pethe, V P

1979-03-01

Focus is on some of the basic issues and considerations involved in the question of compulsion in family planning, which in terms of current contraceptive technology, only means compulsory sterilization. Pressures have been increasing to implement more stringent measures to control population growth in most of the developing countries throughout the world. During the Emergency in India (1975-1977) the government at that time, along with some individuals and groups, deemed it necessary to adopt the drastic measure of compulsory sterilization. The six sections of the discussion deal with the following: 1) compulsory family planning as rational or ethical choice basic issues; 2) neo-Malthusian thesis on compulsion - fallacies, dangers and inadequacies; 3) ethical and philosophical problems - premise of irresponsible procreation; 4) individual rights versus societal interests; 5) elitism in social policy and cost benefit considerations; and 6) international consensus against compulsion. All forums, under the auspices of the United Nations, of which India is a member, have rejected coercion and reiterated repeatedly that every individual has a basic human right to decide how many children to have and at what intervals. The most recent forum to endorse the human right to family size was the World Population Conference held at Bucharest in 1974. The 14 conditions spelled out by the United Nations Fund for Population Activity for effecting a free and responsible choice in family size may form a sound basis for a comprehensive policy concerning family planning in India. The coercive measures adopted during the Emergency are responsible for a backlash in India and retarding the progress of the family planning movement.

Effects of repeated prescribed fires on the structure, composition, and regeneration of mixed-oak forests in Ohio

Treesearch

Todd F. Hutchinson; Elaine Kennedy Sutherland; Daniel A. Yaussy

2005-01-01

This study quantifies prescribed fire effects at four sites in southern Ohio, from 1995 to 2002. Each site had three treatment units: an unburned control, a unit burned 2x (1996 and 1999), and a unit burned 4 x (1996-1999). Vegetation plots were stratified by an integrated moisture index (IMI) into xeric, intermediate, and mesic classes. Prior to treatments, oak (...

Lesser Neural Pattern Similarity across Repeated Tests Is Associated with Better Long-Term Memory Retention.

PubMed

Karlsson Wirebring, Linnea; Wiklund-Hörnqvist, Carola; Eriksson, Johan; Andersson, Micael; Jonsson, Bert; Nyberg, Lars

2015-07-01

Encoding and retrieval processes enhance long-term memory performance. The efficiency of encoding processes has recently been linked to representational consistency: the reactivation of a representation that gets more specific each time an item is further studied. Here we examined the complementary hypothesis of whether the efficiency of retrieval processes also is linked to representational consistency. Alternatively, recurrent retrieval might foster representational variability--the altering or adding of underlying memory representations. Human participants studied 60 Swahili-Swedish word pairs before being scanned with fMRI the same day and 1 week later. On Day 1, participants were tested three times on each word pair, and on Day 7 each pair was tested once. A BOLD signal change in right superior parietal cortex was associated with subsequent memory on Day 1 and with successful long-term retention on Day 7. A representational similarity analysis in this parietal region revealed that beneficial recurrent retrieval was associated with representational variability, such that the pattern similarity on Day 1 was lower for retrieved words subsequently remembered compared with those subsequently forgotten. This was mirrored by a monotonically decreased BOLD signal change in dorsolateral prefrontal cortex on Day 1 as a function of repeated successful retrieval for words subsequently remembered, but not for words subsequently forgotten. This reduction in prefrontal response could reflect reduced demands on cognitive control. Collectively, the results offer novel insights into why memory retention benefits from repeated retrieval, and they suggest fundamental differences between repeated study and repeated testing. Repeated testing is known to produce superior long-term retention of the to-be-learned material compared with repeated encoding and other learning techniques, much because it fosters repeated memory retrieval. This study demonstrates that repeated memory retrieval might strengthen memory by inducing more differentiated or elaborated memory representations in the parietal cortex, and at the same time reducing demands on prefrontal-cortex-mediated cognitive control processes during retrieval. The findings contrast with recent demonstrations that repeated encoding induces less differentiated or elaborated memory representations. Together, this study suggests a potential neurocognitive explanation of why repeated retrieval is more beneficial for long-term retention than repeated encoding, a phenomenon known as the testing effect. Copyright © 2015 the authors 0270-6474/15/359595-08$15.00/0.

Observations and interpretation of fundamental mode Rayleigh wavefields recorded by the Transportable Array (USArray)

USGS Publications Warehouse

Pollitz, F.F.

2008-01-01

Broadband recordings of the dense Transportable Array (TA) in the western United States provide unparalleled detailed images of long-period seismic surface wavefields. With 400 stations spanning most of the western United States, wavefronts of fundamental mode Rayleigh waves may be visualized coherently across the array at periods ???40 s. In order to constrain the Rayleigh wave phase velocity structure in the western United States, I assemble a data set of vertical component seismograms from 53 teleseismic events recorded by the TA from April 2006 to October 2007. Complex amplitude spectra from these recordings at peni ods 27-100 s are interpreted using the multiplane wave tomographic method of Friederich and Wielandt (1995) and Pollitz (1999). This analysis yields detailed surface wave phase velocity and three-dimensional shear wave velocity patterns across the North American plate boundary zone, elucidating the active processes in the highly heterogeneous western U.S. upper mantle.

Development of hydrologic landscape regions for classifying hydrologic permanace and hydrological-ecological interactions

EPA Science Inventory

In a 2001 paper, Winter proposed the concept of the hydrologic landscape unit as a fundamental unit composed of an upland and lowland separated by a steeper slope. Winter suggested that this concept could be useful for hydrologic research, data analysis, and comparing hydrologic...

Introduction to Agricultural Marketing.

ERIC Educational Resources Information Center

Futrell, Gene; And Others

This marketing unit focuses on the importance of forecasting in order for a farm family to develop marketing plans. It describes sources of information and includes a glossary of marketing terms and exercises using both fundamental and technical methods to predict prices in order to improve forecasting ability. The unit is organized in the…

Domestic Refrigeration, Freezer, and Window Air Conditioner Service. Teacher Edition.

ERIC Educational Resources Information Center

Clemons, Mark

This curriculum guide contains six units of instruction for a course in domestic refrigerator, freezer, and window air conditioner service. The units cover the following topics: (1) service fundamentals; (2) mechanical components and functions; (3) electrical components and control devices; (4) refrigerator and freezer service; (5) domestic ice…

Diesel Fundamentals. Teacher Edition (Revised).

ERIC Educational Resources Information Center

Clark, Elton; And Others

This module is one of a series of teaching guides that cover diesel mechanics. The module contains 4 sections and 19 units. Section A--Orientation includes the following units: introduction to diesel mechanics and shop safety; basic shop tools; test equipment and service tools; fasteners; bearings; and seals. Section B--Engine Principles and…

Stochastic and Historical Resonances of the Unit in Physics and Psychometrics

ERIC Educational Resources Information Center

Fisher, William P., Jr.

2011-01-01

Humphry's article, "The Role of the Unit in Physics and Psychometrics," offers fundamental clarifications of measurement concepts that Fisher hopes will find a wide audience. In particular, parameterizing discrimination while preserving statistical sufficiency will indeed provide greater flexibility in accounting "for the effects of empirical…

Programmable Logic Controllers. Teacher Edition.

ERIC Educational Resources Information Center

Rauh, Bob; Kaltwasser, Stan

These materials were developed for a seven-unit secondary or postsecondary education course on programmable logic controllers (PLCs) that treats most of the skills needed to work effectively with PLCs as programming skills. The seven units of the course cover the following topics: fundamentals of programmable logic controllers; contracts, timers,…

Doors to Discovery[TM]. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2013

2013-01-01

"Doors to Discovery"]TM] is a preschool literacy curriculum that uses eight thematic units of activities to help children build fundamental early literacy skills in oral language, phonological awareness, concepts of print, alphabet knowledge, writing, and comprehension. The eight thematic units cover topics such as nature, friendship,…

Creating Attractiveness: The Competitive Challenge for U.S. Industry.

ERIC Educational Resources Information Center

Morita, Akio

1989-01-01

Comments on some fundamentals of trade, suggesting that the world economy has become essentially one transnational unit. Discusses the extent to which Japan and the United States are economically linked. States that protective measures against goods produced abroad are not a solution to any nation's economic problems. (KO)

Discovering Morocco: Using the Five Fundamental Themes of Geography in Order to Discover Morocco

ERIC Educational Resources Information Center

Fitzhugh, William P.

2005-01-01

This curriculum unit, intended to be used with elementary school students, provides information about a North African, Moslem, Arab, country: Morocco. The unit presents objectives, strategies, materials needed, background notes, evaluation methods, and assignments that fulfill National Social Studies Standards and National Geography standards. It…

The Role of Antibody in Korean Word Recognition

ERIC Educational Resources Information Center

Lee, Chang Hwan; Lee, Yoonhyoung; Kim, Kyungil

2010-01-01

A subsyllabic phonological unit, the antibody, has received little attention as a potential fundamental processing unit in word recognition. The psychological reality of the antibody in Korean recognition was investigated by looking at the performance of subjects presented with nonwords and words in the lexical decision task. In Experiment 1, the…

Three Contemporary Dilemmas for Rural Superintendents

ERIC Educational Resources Information Center

Howley, Aimee; Howley, Craig B.; Rhodes, Megan Eliason; Yahn, Jacqueline J.

2014-01-01

The school district is the fundamental administrative unit of schooling in the United States and the superintendent the lead official. The nature and the challenges of this position, however, vary across the landscape. Because most superintendents lead rural districts, the challenges facing those districts are the ones that typically bedevil the…

Graphic Arts: Book Three. The Press and Related Processes.

ERIC Educational Resources Information Center

Farajollahi, Karim; And Others

The third of a three-volume set of instructional materials for a graphic arts course, this manual consists of nine instructional units dealing with presses and related processes. Covered in the units are basic press fundamentals, offset press systems, offset press operating procedures, offset inks and dampening chemistry, preventive maintenance…

Clinical validation of an epigenetic assay to predict negative histopathological results in repeat prostate biopsies.

PubMed

Partin, Alan W; Van Neste, Leander; Klein, Eric A; Marks, Leonard S; Gee, Jason R; Troyer, Dean A; Rieger-Christ, Kimberly; Jones, J Stephen; Magi-Galluzzi, Cristina; Mangold, Leslie A; Trock, Bruce J; Lance, Raymond S; Bigley, Joseph W; Van Criekinge, Wim; Epstein, Jonathan I

2014-10-01

The DOCUMENT multicenter trial in the United States validated the performance of an epigenetic test as an independent predictor of prostate cancer risk to guide decision making for repeat biopsy. Confirming an increased negative predictive value could help avoid unnecessary repeat biopsies. We evaluated the archived, cancer negative prostate biopsy core tissue samples of 350 subjects from a total of 5 urological centers in the United States. All subjects underwent repeat biopsy within 24 months with a negative (controls) or positive (cases) histopathological result. Centralized blinded pathology evaluation of the 2 biopsy series was performed in all available subjects from each site. Biopsies were epigenetically profiled for GSTP1, APC and RASSF1 relative to the ACTB reference gene using quantitative methylation specific polymerase chain reaction. Predetermined analytical marker cutoffs were used to determine assay performance. Multivariate logistic regression was used to evaluate all risk factors. The epigenetic assay resulted in a negative predictive value of 88% (95% CI 85-91). In multivariate models correcting for age, prostate specific antigen, digital rectal examination, first biopsy histopathological characteristics and race the test proved to be the most significant independent predictor of patient outcome (OR 2.69, 95% CI 1.60-4.51). The DOCUMENT study validated that the epigenetic assay was a significant, independent predictor of prostate cancer detection in a repeat biopsy collected an average of 13 months after an initial negative result. Due to its 88% negative predictive value adding this epigenetic assay to other known risk factors may help decrease unnecessary repeat prostate biopsies. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Opinions on Suicide and Perceived Barriers to Care in a Sample of United States Marine Non-Commissioned Officers: Implications for Future Frontline Supervisors’ Suicide Prevention Training Programs

DTIC Science & Technology

2013-11-06

the Scree plot (Figure 3) and the analysis was repeated saving these four factors. The Kaiser - Meyer - Olkin measure of sampling adequacy was .95...the Scree plot (Figure 4) and the analysis was repeated saving these three factors. The Kaiser - Meyer - Olkin measure of sampling adequacy was .90, above

Protocol for multiple node network

NASA Technical Reports Server (NTRS)

Kirkham, Harold (Inventor)

1995-01-01

The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

Protocol for multiple node network

NASA Technical Reports Server (NTRS)

Kirkham, Harold (Inventor)

1994-01-01

The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

Intergenic Variable-Number Tandem-Repeat Polymorphism Upstream of rocA Alters Toxin Production and Enhances Virulence in Streptococcus pyogenes.

PubMed

Zhu, Luchang; Olsen, Randall J; Horstmann, Nicola; Shelburne, Samuel A; Fan, Jia; Hu, Ye; Musser, James M

2016-07-01

Variable-number tandem-repeat (VNTR) polymorphisms are ubiquitous in bacteria. However, only a small fraction of them has been functionally studied. Here, we report an intergenic VNTR polymorphism that confers an altered level of toxin production and increased virulence in Streptococcus pyogenes The nature of the polymorphism is a one-unit deletion in a three-tandem-repeat locus upstream of the rocA gene encoding a sensor kinase. S. pyogenes strains with this type of polymorphism cause human infection and produce significantly larger amounts of the secreted cytotoxins S. pyogenes NADase (SPN) and streptolysin O (SLO). Using isogenic mutant strains, we demonstrate that deleting one or more units of the tandem repeats abolished RocA production, reduced CovR phosphorylation, derepressed multiple CovR-regulated virulence factors (such as SPN and SLO), and increased virulence in a mouse model of necrotizing fasciitis. The phenotypic effect of the VNTR polymorphism was nearly the same as that of inactivating the rocA gene. In summary, we identified and characterized an intergenic VNTR polymorphism in S. pyogenes that affects toxin production and virulence. These new findings enhance understanding of rocA biology and the function of VNTR polymorphisms in S. pyogenes. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Subtle flickering in Cepheids: Kepler and MOST

NASA Astrophysics Data System (ADS)

Evans, Nancy Remage; Szabó, Robert; Szabados, Laszlo; Derekas, Aliz; Matthews, Jaymie M.; Cameron, Chris; the MOST Team

2014-02-01

Fundamental mode classical Cepheids have light curves which repeat accurately enough that we can watch them evolve (change period). The new level of accuracy and quantity of data with the Kepler and MOST satellites probes this further. An intriguing result was found in the long time-series of Kepler data for V1154 Cyg the one classical Cepheid (fundamental mode, P = 4.9 d) in the field, which has short term changes in period (~=20 minutes), correlated for ~=10 cycles (period jitter). To follow this up, we obtained a month long series of observations of the fundamental mode Cepheid RT Aur and the first overtone pulsator SZ Tau. RT Aur shows the traditional strict repetition of the light curve, with the Fourier amplitude ratio R 1/R 2 remaining nearly constant. The light curve of SZ Tau, on the other hand, fluctuates in amplitude ratio at the level of approximately 50%. Furthermore prewhitening the RT Aur data with 10 frequencies reduces the Fourier spectrum to noise. For SZ Tau, considerable power is left after this prewhitening in a complicated variety of frequencies.

Observations of Cepheids with the MOST satellite: contrast between pulsation modes

NASA Astrophysics Data System (ADS)

Evans, N. R.; Szabó, R.; Derekas, A.; Szabados, L.; Cameron, C.; Matthews, J. M.; Sasselov, D.; Kuschnig, R.; Rowe, J. F.; Guenther, D. B.; Moffat, A. F. J.; Rucinski, S. M.; Weiss, W. W.

2015-02-01

The quantity and quality of satellite photometric data strings is revealing details in Cepheid variation at very low levels. Specifically, we observed a Cepheid pulsating in the fundamental mode and one pulsating in the first overtone with the Canadian MOST (Microvariability and Oscillations of Stars) satellite. The 3.7-d period fundamental mode pulsator (RT Aur) has a light curve that repeats precisely, and can be modelled by a Fourier series very accurately. The overtone pulsator (SZ Tau, 3.1 d period) on the other hand shows light-curve variation from cycle to cycle which we characterize by the variations in the Fourier parameters. We present arguments that we are seeing instability in the pulsation cycle of the overtone pulsator, and that this is also a characteristic of the O - C curves of overtone pulsators. On the other hand, deviations from cycle to cycle as a function of pulsation phase follow a similar pattern in both stars, increasing after minimum radius. In summary, pulsation in the overtone pulsator is less stable than that of the fundamental mode pulsator at both long and short time-scales.

Fluid Mechanics: The Pamphlet

NASA Astrophysics Data System (ADS)

Variano, Evan

2012-11-01

One impediment to student learning in introductory fluid mechanics courses is that the fundamental laws of physics can become lost in the ``noise'' of dozens of semi-empirical equations describing special cases. This can be exacerbated by trends in textbooks and other teaching media. This talk will explore a minimalist approach, whereby the entire content of introductory fluids is distilled to a single 1-page pamphlet, designed to emphasize the governing equations and their near-universal applicability. We are particularly interested in hearing feedback from the audience on ways to further distill the content while keeping it accessible and useful. To further emphasize the difference between the fundamental laws and the many specific cases, we have begun assembling a complementary resource: a field guide to fluid phenomena, which mixes the approach of Van Dyke's book with a standard field guide. This is designed to emphasize that there is a ``zoology'' of fluid phenomena, to which the same small set of fundamental laws has been applied repeatedly. These materials may be useful in helping AP Physics teachers cover fluid mechanics, which is an under-utilized opportunity to introduce young scientists to our field of study.

Complete mitochondrial genome of the Asian pencil halfbeak Hyporhamphus intermedius (Beloniformes, Hemirhamphidae).

PubMed

Song, Chao; Hu, Gengdong; Qiu, Liping; Fan, Limin; Meng, Shunlong; Chen, Jiazhang

2016-11-01

The complete mitochondrial genome of Hyporhamphus intermedius was determined to be 16,720 bp in length with (A + T) content of 56.3%, and it consists of 13 protein-coding genes, 22 tRNAs, two ribosomal RNAs, and a control region. The gene composition and the structural arrangement of the H. intermedius complete mtDNA were identical to most of the other vertebrates. Interestingly, two tandem repeat units were identified across tRNA-Pro and control region (2*41 bp), while in most of the fishes the tandem repeat units are located in the control region. The molecular data we presented here could play a useful role to study the evolutionary relationships and population genetics of Hemirhamphidae fish.

Mitochondrial genome of the tomato clownfish Amphiprion frenatus (Pomacentridae, Amphiprioninae).

PubMed

Ye, Le; Hu, Jing; Wu, Kaichang; Wang, Yu; Li, Jianlong

2016-01-01

The complete mitochondrial (mt) genome of the tomato clownfish Amphiprion frenatus was obtained in this study. The circular mtDNA molecule was 16,774 bp in size and the overall nucleotide composition of the H-strand was 29.72% A, 25.81% T, 15.38% G and 29.09% C, with an A + T bias. The complete mitogenome encoded 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a control region (D-loop), with the gene arrangement and translation direction basically identical to other typical vertebrate mitogenomes. The D-loop included termination associated sequence (TAS), central conserved domain (CCD) and conserved sequence block (CSB), and was composed of 6 complete continuity tandem repeat units and an imperfect tandem repeat unit.

Material nature versus structural nurture: the embodied carbon of fundamental structural elements.

PubMed

Purnell, P

2012-01-03

The construction industry is under considerable legislative pressure to reduce its CO(2) emissions. The current focus is on operational CO(2) emissions, but as these are compulsorily reduced, the embodied CO(2) of structural components, overwhelmingly attributable to the material from which they are manufactured, will become of greater interest. Choice of structural materials for minimal embodied CO(2) is currently based either on subjective narrative arguments, or values of embodied CO(2) per unit volume or mass. Here we show that such arguments are invalid. We found that structural design parameters (dimensions, section choice, and load capacity) for fundamental structural components (simple beams and columns) are at least as important as material choice with regard to their effect on embodied CO(2) per unit load capacity per unit dimension, which can vary over several decades within and between material choices. This result demonstrates that relying on apparently objective analyses based on embodied CO(2) per unit volume or mass will not lead to minimum carbon solutions; a formal definition of the correct functional unit for embodied CO(2) must be used. In short, there is no such thing as a green structural material.

Isolation and characterization of microsatellite loci in the intertidal sponge Halichondria panicea

USGS Publications Warehouse

Knowlton, Anne L.; Pierson, Barbara J.; Talbot, S.L.; Highsmith, Ray C.

2003-01-01

GA- and CA-enriched genomic libraries were constructed for the intertidal sponge Halichondria panicea. Unique repeat motifs identified varied from the expected simple dinucleotide repeats to more complex repeat units. All sequences tended to be highly repetitive but did not necessarily contain the targeted motifs. Seven microsatellite loci were evaluated on sponges from the clone source population. All seven were polymorphic with 5.43 ± 0.92 mean number of alleles. Six of the seven loci that could be resolved had mean heterozygosities of 0.14–0.68. The loci identified here will be useful for population studies.

Novel structure of cockroach allergen Bla g 1 has implications for allergenicity and exposure assessment

PubMed Central

Mueller, Geoffrey A.; Pedersen, Lars C.; Lih, Fred B.; Glesner, Jill; Moon, Andrea F.; Chapman, Martin D.; Tomer, Kenneth B.; London, Robert E.; Pomés, Anna

2013-01-01

Background Sensitization to cockroach allergens is a major risk factor for asthma. The cockroach allergen Bla g 1 has multiple repeats of ~100 amino acids, but the fold of the protein and the biological function are unknown. Objective To determine the structure of Bla g 1, investigate the implications for allergic disease, and standardize cockroach exposure assays. Methods Natural Bla g 1 and recombinant constructs were compared by ELISA using specific murine IgG and human IgE. The structure of Bla g 1 was determined by X-ray crystallography. Mass spectrometry and NMR were utilized to examine ligand-binding properties of the allergen. Results The structure of a recombinant Bla g 1 construct with comparable IgE and IgG reactivity to the natural allergen was solved by X-ray crystallography. The Bla g 1 repeat forms a novel fold with 6 helices. Two repeats encapsulate a large and nearly spherical hydrophobic cavity, defining the basic structural unit. Lipids in the cavity varied depending on the allergen origin. Palmitic, oleic and stearic acids were associated with nBla g 1 from cockroach frass. One Unit of Bla g 1 was equivalent to 104 ng of allergen. Conclusions Bla g 1 has a novel fold with a capacity to bind various lipids, which suggests a digestive function associated with non-specific transport of lipid molecules in cockroaches. Defining the basic structural unit of Bla g 1 facilitates the standardization of assays in absolute units for the assessment of environmental allergen exposure. PMID:23915714

Fundamentals of Concrete and Cement Masonry. Instructional Materials.

ERIC Educational Resources Information Center

Hendrix, Laborn J.

This curriculum guide provides materials for a course of instruction designed for training concrete masons who will make their careers in construction. It contains 4 sections and 18 instructional units in a standard format. Eight basic components that form a unit of instruction are performance objectives, suggested activities for the teacher,…

Visualization and Interactivity in the Teaching of Chemistry to Science and Non-Science Students

ERIC Educational Resources Information Center

Venkataraman, Bhawani

2009-01-01

A series of interactive, instructional units have been developed that integrate computational molecular modelling and visualization to teach fundamental chemistry concepts and the relationship between the molecular and macro-scales. The units span the scale from atoms, small molecules to macromolecular systems, and introduce many of the concepts…

Jamestown and Disneyland: Two Places in Time.

ERIC Educational Resources Information Center

Scrofani, E. Robert; Tideman, Robert

This unit for high school students uses two dissimilar places in time; (2) Jamestown, Virginia, founded in 1607, one of the earliest settlements in the United States and (2) Disneyland, California, built in 1956, an institution of contemporary culture. The lessons address two fundamental questions in geography: (1) where? and (2) why here rather…

Mountain Plains Learning Experience Guide: Marketing. Course: Marketing Operations.

ERIC Educational Resources Information Center

Preston, T.; Egan, B.

One of thirteen individualized courses included in a marketing curriculum, this course covers the fundamental concepts of the marketing and distribution field, including the operations of wholesale and retail businesses. The course is comprised of three units: (1) The Marketing Process, (2) Wholesaling, and (3) Retailing. Each unit begins with a…

Air Conditioning and Refrigeration. Book Two.

ERIC Educational Resources Information Center

Wantiez, Gary W.

This curriculum guide (book II), along with book I, is designed to provide students with the basic skills for an occupation in air conditioning and refrigeration. Six major areas are included, each consisting of one or more units of instruction. These areas and their respective units are titled as follows: Electricity (fundamentals of electricity,…

Teaching about Judicial Review. ERIC Digest.

ERIC Educational Resources Information Center

Patrick, John J.

Judicial review is a fundamental facet of constitutional government in the United States. Invented during the founding of the United States, judicial review has spread to most constitutional democracies of the world. This digest discusses: (1) the concept of judicial review; (2) the origin of this concept; (3) the uses of this concept in U.S.…

Fluid Power/Basic Hydraulics. Instructor's Guide.

ERIC Educational Resources Information Center

Stanbery, Richard

This guide is designed to assist industrial vocational instructors in teaching a course on fluid power and basic hydraulics. Covered in the unit on the basics of fluid power and hydraulics are the following topics: the fundamentals of fluid power and hydraulics, basic hydraulic circuits, and servicing a hydraulic jack. The second unit, consisting…

Static and Current Electricity.

ERIC Educational Resources Information Center

Schlenker, Richard M.; Murtha, Kathy T.

This is a copy of the script for the electrical relationships unit in an auto-tutorial physical science course for non-science majors, offered at the University of Maine at Orono. The unit includes 15 simple experiments designed to allow the student to discover various fundamental electrical relationships. The student has the option of reading the…

76 FR 46805 - Agency Information Collection Activities: Notice of Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-03

... Guidelines provide fundamental guidance for all Title VII-covered employers about the use of employment... organizations across the United States in which the unit of analysis is the actual workplace, ( http://www.icpsr... employees. The employer burden associated with collecting and storing applicant demographic data is based on...

76 FR 64086 - Agency Information Collection Activities: Notice of Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-17

.... Abstract: The Uniform Guidelines provide fundamental guidance for all Title VII-covered employers about the... organizations across the United States in which the unit of analysis is the actual workplace, ( http://www.icpsr... employees. The employer burden associated with collecting and storing applicant demographic data is based on...

A Novel CAI System for Space Conceptualization Training in Perspective Sketching

ERIC Educational Resources Information Center

Luh, Ding-Bang; Chen, Shao-Nung

2013-01-01

For many designers, freehand sketching is the primary tool for conceptualization in the early stage of the design process. However, current education on concept presentation techniques rarely emphasizes the construction of the most fundamental spatial unit, the cube. Incorrect construction of spatial units leads to disproportions that deviate from…

Mountain Plains Learning Experience Guide: Marketing. Course: Advertising and Promotion.

ERIC Educational Resources Information Center

Egan, B.

One of thirteen individualized courses included in a marketing curriculum, this course covers the planning and writing of advertisements and organizing sales promotion and public relation activities in wholesale and retail businesses. The course is comprised of two units: (1) Advertising Fundamentals and (2) Promotion. Each unit begins with a Unit…

A Package of Information as the Planck Unit of Information and Also as a Fundamental Physical (Universal) Constant

NASA Astrophysics Data System (ADS)

Gholibeigian, Hassan

Dimension of information as the fifth dimension of the universe including packages of new information, is nested with space-time. Distributed density of information is matched on its correspondence distributed mater in space-time. Fundamental particle (string) like photon and graviton needs a package of information including its exact quantum state and law for process and travel a Planck length in a Planck time. This process is done via sub-particles (substrings). Processed information is carried by particle as the universe's history. My proposed formula for Planck unit of information (IP) and also for Fundamental Physical (Universal) Constant is: IP =lP ct P =1 Planck length lP, Planck time tP, and c , is light speed. Also my proposed formula for calculation of the packages is: I =tP- 1 . τ , in which, I is number of packages, and τ is lifetime of the particle. ``Communication of information'' as a ``fundamental symmetry'' leads phenomena. Packages should be always up to date including new information for evolution of the Universe. But, where come from or how are created new information which Hawking and his colleagues forgot it bring inside the black hole and leave it behind the horizon in form of soft hair?

Gross rearrangements within the 5'-untranslated region of the picornaviral genomes.

PubMed

Pilipenko, E V; Blinov, V M; Agol, V I

1990-06-11

An analysis of reported nucleotide sequences revealed several cases of gross rearrangements in the 5'-untranslated region (5-UTR) of picornaviral genomes. A large (greater than 100 nt) duplication was discovered in a downstream region of poliovirus 5-UTR involved in the translational control. Properties of the poliovirus mutants with large deletions [Kuge and Nomoto (1987) J. Virol. 61, 1478-1487] show that a single copy of the appropriate repeating unit is compatible with a wild type phenotype of the virus. In contrast to poliovirus and another enterovirus genomes, human rhinovirus RNAs contain only a single copy of this repeating unit. Another similarly large repeat was found in an upstream segment of the bovine enterovirus 5-UTR. A comparison of the primary and secondary structures of cardio- and aphthovirus 5-UTRs demonstrated the existence of a large (ca. 250 nucleotides) insertion/deletion in a region preceding the poly(C) tract. The two latter rearrangements appear to involve elements of the viral genome replication machinery. Possible origin as well as evolutionary and functional implications of these structural peculiarities are discussed.

Technologist-Directed Repeat Musculoskeletal and Chest Radiographs: How Often Do They Impact Diagnosis?

PubMed

Rosenkrantz, Andrew B; Jacobs, Jill E; Jain, Nidhi; Brusca-Augello, Geraldine; Mechlin, Michael; Parente, Marc; Recht, Michael P

2017-12-01

Radiologic technologists may repeat images within a radiographic examination because of perceived suboptimal image quality, excluding these original images from submission to a PACS. This study assesses the appropriateness of technologists' decisions to repeat musculoskeletal and chest radiographs as well as the utility of repeat radiographs in addressing examinations' clinical indication. We included 95 musculoskeletal and 87 chest radiographic examinations in which the technologist repeated one or more images because of perceived image quality issues, rejecting original images from PACS submission. Rejected images were retrieved from the radiograph unit and uploaded for viewing on a dedicated server. Musculoskeletal and chest radiologists reviewed rejected and repeat images in their timed sequence, in addition to the studies' remaining images. Radiologists answered questions regarding the added value of repeat images. The reviewing radiologist agreed with the reason for rejection for 64.2% of musculoskeletal and 60.9% of chest radiographs. For 77.9% and 93.1% of rejected radiographs, the clinical inquiry could have been satisfied without repeating the image. For 75.8% and 64.4%, the repeated images showed improved image quality. Only 28.4% and 3.4% of repeated images were considered to provide additional information that was helpful in addressing the clinical question. Most repeated radiographs (chest more so than musculoskeletal radiographs) did not add significant clinical information or alter diagnosis, although they did increase radiation exposure. The decision to repeat images should be made after viewing the questionable image in context with all images in a study and might best be made by a radiologist rather than the performing technologist.

The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior

PubMed Central

Baslow, Morris H.

2011-01-01

The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological “operating system”, a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of “neuronal words and languages” for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic–synaptic–dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA–NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function. PMID:21720525

Using a Virtual Manipulative Environment to Support Students' Organizational Structuring of Volume Units

ERIC Educational Resources Information Center

O'Dell, Jenna R.; Barrett, Jeffrey E.; Cullen, Craig J.; Rupnow, Theodore J.; Clements, Douglas H.; Sarama, Julie; Rutherford, George; Beck, Pamela S.

2017-01-01

In this study, we investigated how Grade 3 and 4 students' organizational structure for volume units develops through repeated experiences with a virtual manipulative for building prisms. Our data consist of taped clinical interviews within a micro-genetic experiment. We report on student strategy development using a virtual manipulative for…

Asian Longhorned Beetle - A New Introduction, Pest Alert

Treesearch

USDA Forest Service, State and Private Forestry, Northeastern Area; Animal and Plant Health Inspection Service

2008-01-01

The Asian longhorned beetle (ALB) has been discovered attacking trees in the United States. Tunneling by beetle larvae girdles tree stems and branches. Repeated attacks lead to dieback of the tree crown and, eventually, death of the tree. ALB probably traveled to the United States inside solid wood packing material from China. The beetle has been intercepted at ports...

Exploring the repeat protein universe through computational protein design

DOE PAGES

Brunette, TJ; Parmeggiani, Fabio; Huang, Po-Ssu; ...

2015-12-16

A central question in protein evolution is the extent to which naturally occurring proteins sample the space of folded structures accessible to the polypeptide chain. Repeat proteins composed of multiple tandem copies of a modular structure unit are widespread in nature and have critical roles in molecular recognition, signalling, and other essential biological processes. Naturally occurring repeat proteins have been re-engineered for molecular recognition and modular scaffolding applications. In this paper, we use computational protein design to investigate the space of folded structures that can be generated by tandem repeating a simple helix–loop–helix–loop structural motif. Eighty-three designs with sequences unrelatedmore » to known repeat proteins were experimentally characterized. Of these, 53 are monomeric and stable at 95 °C, and 43 have solution X-ray scattering spectra consistent with the design models. Crystal structures of 15 designs spanning a broad range of curvatures are in close agreement with the design models with root mean square deviations ranging from 0.7 to 2.5 Å. Finally, our results show that existing repeat proteins occupy only a small fraction of the possible repeat protein sequence and structure space and that it is possible to design novel repeat proteins with precisely specified geometries, opening up a wide array of new possibilities for biomolecular engineering.« less

Fostering repeat donations in Ghana.

PubMed

Owusu-Ofori, S; Asenso-Mensah, K; Boateng, P; Sarkodie, F; Allain, J-P

2010-01-01

Most African countries are challenged in recruiting and retaining voluntary blood donors by cost and other complexities and in establishing and implementing national blood policies. The availability of replacement donors who are a cheaper source of blood has not enhanced repeat voluntary donor initiatives. An overview of activities for recruiting and retaining voluntary blood donors was carried out. Donor records from mobile sessions were reviewed from 2002 to 2008. A total of 71,701 blood donations; 45,515 (63.5%) being voluntary donations with 11,680 (25%) repeat donations were collected during the study period. Donations from schools and colleges contributed a steady 60% of total voluntary whilst radio station blood drives increased contribution from 10 to 27%. Though Muslim population is less than 20%, blood collection was above the 30-donation cost-effectiveness threshold with a repeat donation trend reaching 60%. In contrast Christian worshippers provided <25 unit/session and 30% repeat donations. Repeat donation trends amongst school donors and radio blood drives were 20% and 70% respectively. Repeat donations rates have been variable amongst different blood donor groups in Kumasi, Ghana. The impact of community leaders in propagating altruism cannot be overemphasized. Programs aiming at motivating replacement donors to be repeat donors should be developed and assessed. Copyright 2009 The International Association for Biologicals. All rights reserved.

Cellular computational platform and neurally inspired elements thereof

DOEpatents

Okandan, Murat

2016-11-22

A cellular computational platform is disclosed that includes a multiplicity of functionally identical, repeating computational hardware units that are interconnected electrically and optically. Each computational hardware unit includes a reprogrammable local memory and has interconnections to other such units that have reconfigurable weights. Each computational hardware unit is configured to transmit signals into the network for broadcast in a protocol-less manner to other such units in the network, and to respond to protocol-less broadcast messages that it receives from the network. Each computational hardware unit is further configured to reprogram the local memory in response to incoming electrical and/or optical signals.

Characterization of natural photonic crystals in iridescent wings of damselfly Chalcopteryx rutilans by FIB/SEM, TEM, and TOF-SIMS.

PubMed

Carr, David M; Ellsworth, Ashley A; Fisher, Gregory L; Valeriano, Wescley W; Vasco, Juan P; Guimarães, Paulo S S; de Andrade, Rodrigo R; da Silva, Elizabeth R; Rodrigues, Wagner N

2018-02-05

The iridescent wings of the Chalcopterix rutilans damselfly (Rambur) (Odonata, Polythoridae) are investigated with focused ion beam/scanning electron microscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry. The electron microscopy images reveal a natural photonic crystal as the source of the varying colors. The photonic crystal has a consistent number and thickness (∼195 nm) of the repeat units on the ventral side of the wing, which is consistent with the red color visible from the bottom side of the wing in all regions. The dorsal side of the wing shows strong color variations ranging from red to blue depending on the region. In the electron microscopy images, the dorsal side of the wing exhibits varied number and thicknesses of the repeat units. The repeat unit spacings for the red, yellow/green, and blue regions are approximately 195, 180, and 145 nm, respectively. Three-dimensional analysis of the natural photonic crystals by time-of-flight secondary ion mass spectrometry reveals that changes in the relative levels of Na, K, and eumelanin are responsible for the varying dielectric constant needed to generate the photonic crystal. The photonic crystal also appears to be assembled with a chemical tricomponent layer structure due to the enhancement of the CH 6 N 3 + species at every other interface between the high/low dielectric constant layers.

Characterization of (CA)n microsatellite repeats from large-insert clones.

PubMed

Litt, M; Browne, D

2001-05-01

The most laborious part of developing (CA)n microsatellite repeats as genetic markers is constructing DNA clones to permit determination of sequences flanking the microsatellites. When cosmids or large-insert phage clones are used as primary sources of (CA)n repeat markers, they have traditionally been subcloned into plasmid vectors such as pUC18 or M13 mp 18/19 cloning vectors to obtain fragments of suitable size for DNA sequencing. This unit presents an alternative approach whereby a set of degenerate sequencing primers that anneal directly to (CA)n microsatellites can be used to determine sequences that are inaccessible with vector-derived primers. Because the primers anneal to the repeat and not to the vector, they can be used with subclones containing inserts of several kilobases and should, in theory, always give sequence in the regions directly flanking the repeat. Degeneracy at the 3 end of each of these primers prevents elongation of primers that have annealed out-of-register. The most laborious part of developing (CA)n microsatellite repeats as genetic markers is constructing DNA clones to permit.

SSRscanner: a program for reporting distribution and exact location of simple sequence repeats

PubMed Central

Anwar, Tamanna; Khan, Asad U

2006-01-01

Simple sequence repeats (SSRs) have become important molecular markers for a broad range of applications, such as genome mapping and characterization, phenotype mapping, marker assisted selection of crop plants and a range of molecular ecology and diversity studies. These repeated DNA sequences are found in both prokaryotes and eukaryotes. They are distributed almost at random throughout the genome, ranging from mononucleotide to trinucleotide repeats. They are also found at longer lengths (> 6 repeating units) of tracts. Most of the computer programs that find SSRs do not report its exact position. A computer program SSRscanner was written to find out distribution, frequency and exact location of each SSR in the genome. SSRscanner is user friendly. It can search repeats of any length and produce outputs with their exact position on chromosome and their frequency of occurrence in the sequence. Availability This program has been written in PERL and is freely available for non-commercial users by request from the authors. Please contact the authors by E-mail: huzzi99@hotmail.com PMID:17597863

Electromagnetic Fields and Human Health: Fundamental and Applied Research. Proceeding of the International Conference (3rd) Held in Moscow and St. Petersburg, Russia, September 17-25 2002

DTIC Science & Technology

2002-10-28

repeatedly similar to those observed in a standard hatchery. In a series of seven replicates, eggs issued from artificially inseminated hens (200 x 106 spz...intercellular information channel leading to the negative con- sequences for the organism. Likely the magnet storms the artificial change of magnet field...biochemical reactions that can be affected by such pulses. We shall present data that shows an artificially contrived biochemical reaction, the

Micro-XRF : Elemental Analysis for In Situ Geology and Astrobiology Exploration

NASA Technical Reports Server (NTRS)

Allwood, Abigail; Hodyss, Robert; Wade, Lawrence

2012-01-01

The ability to make close-up measurements of rock chemistry is one of the most fundamental tools for astrobiological exploration of Mars and other rocky bodies of the solar system. When conducting surface-based exploration, lithochemical measurements provide critical data that enable interpretation of the local geology, which in turn is vital for determining habitability and searching for evidence of life. The value of lithochemical measurements for geological interpretations has been repeatedly demonstrated with virtually every landed Mars mission over the past four decades.

The Republicanization of evangelical Protestants in the United States: An examination of the sources of political realignment.

PubMed

Schwadel, Philip

2017-02-01

Although the association between evangelical Protestant and Republican affiliations is now a fundamental aspect of American politics, this was not the case as recently as the early 1980s. Following work on secular political realignment and the issue evolution model of partisan change, I use four decades of repeated cross-sectional survey data to examine the dynamic correlates of evangelical Protestant and Republican affiliations, and how these factors promote changes in partisanship. Results show that evangelical Protestants have become relatively more likely to attend religious services and to oppose homosexuality, abortion, and welfare spending. Period-specific mediation models show that opposition to abortion, homosexuality, and welfare spending have become more robust predictors of Republican affiliation. By the twenty-first century, differences in Republican affiliation between evangelical Protestants and other religious affiliates are fully mediated by views of homosexuality, abortion, and welfare spending; and differences in Republican affiliation between evangelicals and the religiously unaffiliated are substantially mediated by views of homosexuality, abortion, welfare spending, and military spending. These results further understanding of rapid changes in politico-religious alignments and the increasing importance of moral and cultural issues in American politics, which supports a culture wars depiction of the contemporary political landscape. Copyright © 2016 Elsevier Inc. All rights reserved.

Anatomical Calibration through Post-Processing of Standard Motion Tests Data.

PubMed

Kong, Weisheng; Sessa, Salvatore; Zecca, Massimiliano; Takanishi, Atsuo

2016-11-28

The inertial measurement unit is popularly used as a wearable and flexible tool for human motion tracking. Sensor-to-body alignment, or anatomical calibration (AC), is fundamental to improve accuracy and reliability. Current AC methods either require extra movements or are limited to specific joints. In this research, the authors propose a novel method to achieve AC from standard motion tests (such as walking, or sit-to-stand), and compare the results with the AC obtained from specially designed movements. The proposed method uses the limited acceleration range on medial-lateral direction, and applies principal component analysis to estimate the sagittal plane, while the vertical direction is estimated from acceleration during quiet stance. The results show a good correlation between the two sets of IMUs placed on frontal/back and lateral sides of head, trunk and lower limbs. Moreover, repeatability and convergence were verified. The AC obtained from sit-to-stand and walking achieved similar results as the movements specifically designed for upper and lower body AC, respectively, except for the feet. Therefore, the experiments without AC performed can be recovered through post-processing on the walking and sit-to-stand data. Moreover, extra movements for AC can be avoided during the experiment and instead achieved through the proposed method.

The role of internal duplication in the evolution of multi-domain proteins.

PubMed

Nacher, J C; Hayashida, M; Akutsu, T

2010-08-01

Many proteins consist of several structural domains. These multi-domain proteins have likely been generated by selective genome growth dynamics during evolution to perform new functions as well as to create structures that fold on a biologically feasible time scale. Domain units frequently evolved through a variety of genetic shuffling mechanisms. Here we examine the protein domain statistics of more than 1000 organisms including eukaryotic, archaeal and bacterial species. The analysis extends earlier findings on asymmetric statistical laws for proteome to a wider variety of species. While proteins are composed of a wide range of domains, displaying a power-law decay, the computation of domain families for each protein reveals an exponential distribution, characterizing a protein universe composed of a thin number of unique families. Structural studies in proteomics have shown that domain repeats, or internal duplicated domains, represent a small but significant fraction of genome. In spite of its importance, this observation has been largely overlooked until recently. We model the evolutionary dynamics of proteome and demonstrate that these distinct distributions are in fact rooted in an internal duplication mechanism. This process generates the contemporary protein structural domain universe, determines its reduced thickness, and tames its growth. These findings have important implications, ranging from protein interaction network modeling to evolutionary studies based on fundamental mechanisms governing genome expansion.

Fungal Melanins Differ in Planar Stacking Distances

PubMed Central

Casadevall, Arturo; Nakouzi, Antonio; Crippa, Pier R.; Eisner, Melvin

2012-01-01

Melanins are notoriously difficult to study because they are amorphous, insoluble and often associated with other biological materials. Consequently, there is a dearth of structural techniques to study this enigmatic pigment. Current models of melanin structure envision the stacking of planar structures. X ray diffraction has historically been used to deduce stacking parameters. In this study we used X ray diffraction to analyze melanins derived from Cryptococcus neoformans, Aspergillus niger, Wangiella dermatitides and Coprinus comatus. Analysis of melanin in melanized C. neoformans encapsulated cells was precluded by the fortuitous finding that the capsular polysaccharide had a diffraction spectrum that was similar to that of isolated melanin. The capsular polysaccharide spectrum was dominated by a broad non-Bragg feature consistent with origin from a repeating structural motif that may arise from inter-molecular interactions and/or possibly gel organization. Hence, we isolated melanin from each fungal species and compared diffraction parameters. The results show that the inferred stacking distances of fungal melanins differ from that reported for synthetic melanin and neuromelanin, occupying intermediate position between these other melanins. These results suggest that all melanins have a fundamental diffracting unit composed of planar graphitic assemblies that can differ in stacking distance. The stacking peak appears to be a distinguishing universal feature of melanins that may be of use in characterizing these enigmatic pigments. PMID:22359541

Solution‐crystallization and related phenomena in 9,9‐dialkyl‐fluorene polymers. II. Influence of side‐chain structure

PubMed Central

Perevedentsev, Aleksandr; Stavrinou, Paul N.; Smith, Paul

2015-01-01

ABSTRACT Solution‐crystallization is studied for two polyfluorene polymers possessing different side‐chain structures. Thermal analysis and temperature‐dependent optical spectroscopy are used to clarify the nature of the crystallization process, while X‐ray diffraction and scanning electron microscopy reveal important differences in the resulting microstructures. It is shown that the planar‐zigzag chain conformation termed the β‐phase, which is observed for certain linear‐side‐chain polyfluorenes, is necessary for the formation of so‐called polymer‐solvent compounds for these polymers. Introduction of alternating fluorene repeat units with branched side‐chains prevents formation of the β‐phase conformation and results in non‐solvated, i.e. melt‐crystallization‐type, polymer crystals. Unlike non‐solvated polymer crystals, for which the chain conformation is stabilized by its incorporation into a crystalline lattice, the β‐phase conformation is stabilized by complexation with solvent molecules and, therefore, its formation does not require specific inter‐chain interactions. The presented results clarify the fundamental differences between the β‐phase and other conformational/crystalline forms of polyfluorenes. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1492–1506 PMID:27546983

Design ATE systems for complex assemblies

NASA Astrophysics Data System (ADS)

Napier, R. S.; Flammer, G. H.; Moser, S. A.

1983-06-01

The use of ATE systems in radio specification testing can reduce the test time by approximately 90 to 95 percent. What is more, the test station does not require a highly trained operator. Since the system controller has full power over all the measurements, human errors are not introduced into the readings. The controller is immune to any need to increase output by allowing marginal units to pass through the system. In addition, the software compensates for predictable, repeatable system errors, for example, cabling losses, which are an inherent part of the test setup. With no variation in test procedures from unit to unit, there is a constant repeatability factor. Preparing the software, however, usually entails considerable expense. It is pointed out that many of the problems associated with ATE system software can be avoided with the use of a software-intensive, or computer-intensive, system organization. Its goal is to minimize the user's need for software development, thereby saving time and money.

Stabilization of perfect and imperfect tandem repeats by single-strand DNA exonucleases

PubMed Central

Feschenko, Vladimir V.; Rajman, Luis A.; Lovett, Susan T.

2003-01-01

Rearrangements between tandemly repeated DNA sequences are a common source of genetic instability. Such rearrangements underlie several human genetic diseases. In many organisms, the mismatch-repair (MMR) system functions to stabilize repeats when the repeat unit is short or when sequence imperfections are present between the repeats. We show here that the action of single-stranded DNA (ssDNA) exonucleases plays an additional, important role in stabilizing tandem repeats, independent of their role in MMR. For perfect repeats of ≈100 bp in Escherichia coli that are not susceptible to MMR, exonuclease (Exo)-I, ExoX, and RecJ exonuclease redundantly inhibit deletion. Our data suggest that >90% of potential deletion events are avoided by the combined action of these three exonucleases. Imperfect tandem repeats, less prone to rearrangements, are stabilized by both the MMR-pathway and ssDNA-specific exonucleases. For 100-bp repeats containing four mispairs, ExoI alone aborts most deletion events, even in the presence of a functional MMR system. By genetic analysis, we show that the inhibitory effect of ssDNA exonucleases on deletion formation is independent of the MutS and UvrD proteins. Exonuclease degradation of DNA displaced during the deletion process may abort slipped misalignment. Exonuclease action is therefore a significant force in genetic stabilization of many forms of repetitive DNA. PMID:12538867

Centrifuge Facility for the International Space Station Alpha

NASA Technical Reports Server (NTRS)

Johnson, Catherine C.; Hargens, Alan R.

1994-01-01

The Centrifuge Facility planned for the International Space Station Alpha has under-one considerable redesign over the past year, primarily because the Station is now viewed as a 10 year mission rather than a 30 year mission and because of the need to simply the design to meet budget constraints and a 2000 launch date. The basic elements of the Centrifuge Facility remain the same, i.e., a 2.5 m diameter centrifuge, a micro-g holding unit, plant and animal habitats, a glovebox and a service unit. The centrifuge will still provide the full range of artificial gravity from 0.01 a to 2 - as originally planned; however, the extractor to permit withdrawal of habitats from the centrifuge without stopping the centrifuge has been eliminated. The specimen habitats have also been simplified and are derived from other NASA programs. The Plant Research Unit being developed by the Gravitational Biology Facility will be used to house plants in the Centrifuge Facility. Although not as ambitious as the Centrifuge Facility plant habitat, it will provide much better environmental control and lighting than the current Shuttle based Plant Growth Facility. Similarly, rodents will be housed in the Advanced Animal Habitat being developed for the Shuttle program. The Centrifuge Facility and ISSA will provide the opportunity to perform repeatable, high quality science. The long duration increments available on the Station will permit multigeneration studies on both plants and animals which have not previously been possible. The Centrifuge Facility will accommodate sufficient number of specimens to permit statistically significant sampling of specimens to investigate the time course of adaptation to altered gravity environments. The centrifuge will for the first time permit investigators to use gravity itself as a tool to investigate fundamental processes, to investigate the intensity and duration of gravity to maintain normal structure and function, to separate the effects of micro-g from other 0 environmental factors and to examine artificial gravity as a potential countermeasure for the physical deconditioning observed during spaceflight.

Rational design of alpha-helical tandem repeat proteins with closed architectures

PubMed Central

Doyle, Lindsey; Hallinan, Jazmine; Bolduc, Jill; Parmeggiani, Fabio; Baker, David; Stoddard, Barry L.; Bradley, Philip

2015-01-01

Tandem repeat proteins, which are formed by repetition of modular units of protein sequence and structure, play important biological roles as macromolecular binding and scaffolding domains, enzymes, and building blocks for the assembly of fibrous materials1,2. The modular nature of repeat proteins enables the rapid construction and diversification of extended binding surfaces by duplication and recombination of simple building blocks3,4. The overall architecture of tandem repeat protein structures – which is dictated by the internal geometry and local packing of the repeat building blocks – is highly diverse, ranging from extended, super-helical folds that bind peptide, DNA, and RNA partners5–9, to closed and compact conformations with internal cavities suitable for small molecule binding and catalysis10. Here we report the development and validation of computational methods for de novo design of tandem repeat protein architectures driven purely by geometric criteria defining the inter-repeat geometry, without reference to the sequences and structures of existing repeat protein families. We have applied these methods to design a series of closed alpha-solenoid11 repeat structures (alpha-toroids) in which the inter-repeat packing geometry is constrained so as to juxtapose the N- and C-termini; several of these designed structures have been validated by X-ray crystallography. Unlike previous approaches to tandem repeat protein engineering12–20, our design procedure does not rely on template sequence or structural information taken from natural repeat proteins and hence can produce structures unlike those seen in nature. As an example, we have successfully designed and validated closed alpha-solenoid repeats with a left-handed helical architecture that – to our knowledge – is not yet present in the protein structure database21. PMID:26675735

Decentralizing Centralized Control: Reorienting a Fundamental Tenet for Resilient Air Operation

DTIC Science & Technology

2008-05-22

Forward Air Controller FBIS Foreign Broadcast Information Service FCC Functional Component Commander FM Field Manual GBU - 39 Guided Bomb Unit - 39...Diameter Bomb ( GBU - 39 ) TEG Test and Evaluation Group TST Time Sensitive Target UAV Unmanned Aerial Vehicle USAF United States Air Force USAFWS United...www.afmc.af.mil/news/story.asp?id=123017916 (accessed November 11, 2007). Recent fielding of the GBU - 39 , Small Diameter Bomb (SDB), enables a

Different mechanisms are involved in the transcriptional activation by yeast heat shock transcription factor through two different types of heat shock elements.

PubMed

Hashikawa, Naoya; Yamamoto, Noritaka; Sakurai, Hiroshi

2007-04-06

The hydrophobic repeat is a conserved structural motif of eukaryotic heat shock transcription factor (HSF) that enables HSF to form a homotrimer. Homotrimeric HSF binds to heat shock elements (HSEs) consisting of three inverted repeats of the sequence nGAAn. Sequences consisting of four or more nGAAn units are bound cooperatively by two HSF trimers. We show that in Saccharomyces cerevisiae cells oligomerization-defective Hsf1 is not able to bind HSEs with three units and is not extensively phosphorylated in response to stress; it is therefore unable to activate genes containing this type of HSE. Several lines of evidence indicate that oligomerization is a prerequisite for stress-induced hyperphosphorylation of Hsf1. In contrast, oligomerization and hyperphosphorylation are not necessary for gene activation via HSEs with four units. Intragenic suppressor screening of oligomerization-defective hsf1 showed that an interface between adjacent DNA-binding domains is important for the binding of Hsf1 to the HSE. We suggest that Saccharomyces cerevisiae HSEs with different structures are regulated differently; HSEs with three units require Hsf1 to be both oligomerized and hyperphosphorylated, whereas HSEs with four or more units do not require either.

2-D Structure of the A Region of Xist RNA and Its Implication for PRC2 Association

PubMed Central

Maenner, Sylvain; Blaud, Magali; Fouillen, Laetitia; Savoye, Anne; Marchand, Virginie; Dubois, Agnès; Sanglier-Cianférani, Sarah; Van Dorsselaer, Alain; Clerc, Philippe; Avner, Philip; Visvikis, Athanase; Branlant, Christiane

2010-01-01

In placental mammals, inactivation of one of the X chromosomes in female cells ensures sex chromosome dosage compensation. The 17 kb non-coding Xist RNA is crucial to this process and accumulates on the future inactive X chromosome. The most conserved Xist RNA region, the A region, contains eight or nine repeats separated by U-rich spacers. It is implicated in the recruitment of late inactivated X genes to the silencing compartment and likely in the recruitment of complex PRC2. Little is known about the structure of the A region and more generally about Xist RNA structure. Knowledge of its structure is restricted to an NMR study of a single A repeat element. Our study is the first experimental analysis of the structure of the entire A region in solution. By the use of chemical and enzymatic probes and FRET experiments, using oligonucleotides carrying fluorescent dyes, we resolved problems linked to sequence redundancies and established a 2-D structure for the A region that contains two long stem-loop structures each including four repeats. Interactions formed between repeats and between repeats and spacers stabilize these structures. Conservation of the spacer terminal sequences allows formation of such structures in all sequenced Xist RNAs. By combination of RNP affinity chromatography, immunoprecipitation assays, mass spectrometry, and Western blot analysis, we demonstrate that the A region can associate with components of the PRC2 complex in mouse ES cell nuclear extracts. Whilst a single four-repeat motif is able to associate with components of this complex, recruitment of Suz12 is clearly more efficient when the entire A region is present. Our data with their emphasis on the importance of inter-repeat pairing change fundamentally our conception of the 2-D structure of the A region of Xist RNA and support its possible implication in recruitment of the PRC2 complex. PMID:20052282

CRISPRcompar: a website to compare clustered regularly interspaced short palindromic repeats.

PubMed

Grissa, Ibtissem; Vergnaud, Gilles; Pourcel, Christine

2008-07-01

Clustered regularly interspaced short palindromic repeat (CRISPR) elements are a particular family of tandem repeats present in prokaryotic genomes, in almost all archaea and in about half of bacteria, and which participate in a mechanism of acquired resistance against phages. They consist in a succession of direct repeats (DR) of 24-47 bp separated by similar sized unique sequences (spacers). In the large majority of cases, the direct repeats are highly conserved, while the number and nature of the spacers are often quite diverse, even among strains of a same species. Furthermore, the acquisition of new units (DR + spacer) was shown to happen almost exclusively on one side of the locus. Therefore, the CRISPR presents an interesting genetic marker for comparative and evolutionary analysis of closely related bacterial strains. CRISPRcompar is a web service created to assist biologists in the CRISPR typing process. Two tools facilitates the in silico investigation: CRISPRcomparison and CRISPRtionary. This website is freely accessible at http://crispr.u-psud.fr/CRISPRcompar/.

Inter- and intraobserver repeatability of the Salford Gait Tool: an observation-based clinical gait assessment tool.

PubMed

Toro, Brigitte; Nester, Christopher J; Farren, Pauline C

2007-03-01

To evaluate the inter- and intraobserver repeatability of the Salford Gait Tool (SF-GT), a new observation-based gait assessment tool for evaluating sagittal plane cerebral palsy (CP) gait. Masked comparative evaluation. University in the United Kingdom. A convenience sample of 23 pediatric physical therapists with varying degrees of clinical experience recruited from the Greater Manchester area. Participants viewed videotapes of the sagittal plane gait of 13 children and used the SF-GT to analyze their 13 different gait styles on 2 occasions. Eleven children had hemiplegic, diplegic, or quadriplegic CP and 2 were neurologically intact. Inter- and intraobserver repeatability of hip, knee, and ankle joint positions at 6 different phases of the gait cycle. The SF-GT demonstrated good interobserver (77%) and intraobserver (75%) repeatability. We have established that the SF-GT is a repeatable clinical assessment tool with which to guide the diagnosis, treatment planning, and evaluation of interventions by pediatric physical therapists of sagittal plane gait deviations in CP.

Poly(phenylene)-based anion exchange membrane

DOEpatents

Hibbs, Michael [Albuquerque, NM; Cornelius, Christopher J [Albuquerque, NM; Fujimoto, Cy H [Albuquerque, NM

2011-02-15

A poly(phenylene) compound of copolymers that can be prepared with either random or multiblock structures where a first polymer has a repeat unit with a structure of four sequentially connected phenyl rings with a total of 2 pendant phenyl groups and 4 pendant tolyl groups and the second polymer has a repeat unit with a structure of four sequentially connected phenyl rings with a total of 6 pendant phenyl groups. The second polymer has chemical groups attached to some of the pendant phenyl groups selected from CH.sub.3, CH.sub.2Br, and CH.sub.2N(CH.sub.3).sub.3Br groups. When at least one group is CH.sub.2N(CH.sub.3).sub.3Br, the material functions as an anion exchange membrane.

Comparison of current meters used for stream gaging

USGS Publications Warehouse

Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.

1994-01-01

The U.S. Geological Survey (USGS) is field and laboratory testing the performance of several current meters used throughout the world for stream gaging. Meters tested include horizontal-axis current meters from Germany, the United Kingdom, and the People's Republic of China, and vertical-axis and electromagnetic current meters from the United States. Summarized are laboratory test results for meter repeatability, linearity, and response to oblique flow angles and preliminary field testing results. All current meters tested were found to under- and over-register velocities; errors usually increased as the velocity and angle of the flow increased. Repeatability and linearity of all meters tested were good. In the field tests, horizontal-axis meters, except for the two meters from the People's Republic of China, registered higher velocity than did the vertical-axis meters.

Repeated unit cell (RUC) approach for pure bending analysis of coronary stents.

PubMed

Ju, Feng; Xia, Zihui; Zhou, Chuwei

2008-08-01

Flexibility is one of the key properties of coronary stents. The objective of this paper is to characterize the bending behaviour of stents through finite element analysis with repeated unit cell (RUC) models. General periodic boundary conditions for the RUC under the pure bending condition are formulated. It is found that the proposed RUC approach can provide accurate numerical results of bending behaviour of stents with much less computational costs. Bending stiffness, post-yield bending behaviour and the relationship between moment and bending curvature are investigated for Palmaz-Schatz stents and stents with the V- and S-shaped links. It is found that the effect of link geometry on the bending behaviour of stent is significant. The behaviour of stents subjected to cyclic bending is also investigated.

Studies on the primary structure of short polysaccharides using SEC MALDI mass spectroscopy.

PubMed

Garozzo, D; Spina, E; Cozzolino, R; Cescutti, P; Fett, W F

2000-01-12

The introduction of size-exclusion chromatography (SEC) analysis of polysaccharides prior to MALDI mass spectroscopy accounts for the determination of the molecular mass of the repeating unit when neutral homopolymers are investigated. In the case of natural polysaccharides characterised by more complicated structural features (presence of non-carbohydrate substituents, charged groups, etc.), this mass value usually is in agreement with more than one sugar composition. Therefore, it is not sufficient to give the correct monosaccharidic composition of the polysaccharide investigated. To solve this problem, MALDI spectra were recorded on the permethylated sample and post-source decay experiments were performed on precursor ions. In this way, the composition (in terms of Hex, HexNAc, etc.), size and sequence of the repeating unit were determined.

Clustered regularly interspaced short palindromic repeats (CRISPRs): the hallmark of an ingenious antiviral defense mechanism in prokaryotes.

PubMed

Al-Attar, Sinan; Westra, Edze R; van der Oost, John; Brouns, Stan J J

2011-04-01

Many prokaryotes contain the recently discovered defense system against mobile genetic elements. This defense system contains a unique type of repetitive DNA stretches, termed Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs). CRISPRs consist of identical repeated DNA sequences (repeats), interspaced by highly variable sequences referred to as spacers. The spacers originate from either phages or plasmids and comprise the prokaryotes' 'immunological memory'. CRISPR-associated (cas) genes encode conserved proteins that together with CRISPRs make-up the CRISPR/Cas system, responsible for defending the prokaryotic cell against invaders. CRISPR-mediated resistance has been proposed to involve three stages: (i) CRISPR-Adaptation, the invader DNA is encountered by the CRISPR/Cas machinery and an invader-derived short DNA fragment is incorporated in the CRISPR array. (ii) CRISPR-Expression, the CRISPR array is transcribed and the transcript is processed by Cas proteins. (iii) CRISPR-Interference, the invaders' nucleic acid is recognized by complementarity to the crRNA and neutralized. An application of the CRISPR/Cas system is the immunization of industry-relevant prokaryotes (or eukaryotes) against mobile-genetic invasion. In addition, the high variability of the CRISPR spacer content can be exploited for phylogenetic and evolutionary studies. Despite impressive progress during the last couple of years, the elucidation of several fundamental details will be a major challenge in future research.

Re-examining the upper limit of temporal pitch

PubMed Central

Macherey, Olivier; Carlyon, Robert P.

2015-01-01

Five normally-hearing listeners pitch-ranked harmonic complexes of different fundamental frequencies (F0s) filtered in three different frequency regions. Harmonics were summed either in sine, alternating sine-cosine (ALT), or pulse-spreading (PSHC) phase. The envelopes of ALT and PSHC complexes repeated at rates of 2F0 and 4F0. Pitch corresponded to those rates at low F0s, but, as F0 increased, there was a range of F0s over which pitch remained constant or dropped. Gammatone-filterbank simulations showed that, as F0 increased and the number of harmonics interacting in a filter dropped, the output of that filter switched from repeating at 2F0 or 4F0 to repeating at F0. A model incorporating this phenomenon accounted well for the data, except for complexes filtered into the highest frequency region (7800-10800 Hz). To account for the data in that region it was necessary to assume either that auditory filters at very high frequencies are sharper than traditionally believed, and/or that the auditory system applies smaller weights to filters whose outputs repeat at high rates. The results also provide new evidence on the highest pitch that can be derived from purely temporal cues, and corroborate recent reports that a complex pitch can be derived from very-high-frequency resolved harmonics. PMID:25480066

Distinct C9orf72-Associated Dipeptide Repeat Structures Correlate with Neuronal Toxicity

PubMed Central

Krans, Amy; Sawaya, Michael R.; Paulson, Henry L.; Todd, Peter K.; Barmada, Sami J.; Ivanova, Magdalena I.

2016-01-01

Hexanucleotide repeat expansions in C9orf72 are the most common inherited cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The expansions elicit toxicity in part through repeat-associated non-AUG (RAN) translation of the intronic (GGGGCC)n sequence into dipeptide repeat-containing proteins (DPRs). Little is known, however, about the structural characteristics and aggregation propensities of the dipeptide units comprising DPRs. To address this question, we synthesized dipeptide units corresponding to the three sense-strand RAN translation products, analyzed their structures by circular dichroism, electron microscopy and dye binding assays, and assessed their relative toxicity when applied to primary cortical neurons. Short, glycine-arginine (GR)3 dipeptides formed spherical aggregates and selectively reduced neuronal survival compared to glycine-alanine (GA)3 and glycine-proline (GP)3 dipeptides. Doubling peptide length had little effect on the structure of GR or GP peptides, but (GA)6 peptides formed β-sheet rich aggregates that bound thioflavin T and Congo red yet lacked the typical fibrillar morphology of amyloids. Aging of (GA)6 dipeptides increased their β-sheet content and enhanced their toxicity when applied to neurons. We also observed that the relative toxicity of each tested dipeptide was proportional to peptide internalization. Our results demonstrate that different C9orf72-related dipeptides exhibit distinct structural properties that correlate with their relative toxicity. PMID:27776165

Memory for sequences of events impaired in typical aging.

PubMed

Allen, Timothy A; Morris, Andrea M; Stark, Shauna M; Fortin, Norbert J; Stark, Craig E L

2015-03-01

Typical aging is associated with diminished episodic memory performance. To improve our understanding of the fundamental mechanisms underlying this age-related memory deficit, we previously developed an integrated, cross-species approach to link converging evidence from human and animal research. This novel approach focuses on the ability to remember sequences of events, an important feature of episodic memory. Unlike existing paradigms, this task is nonspatial, nonverbal, and can be used to isolate different cognitive processes that may be differentially affected in aging. Here, we used this task to make a comprehensive comparison of sequence memory performance between younger (18-22 yr) and older adults (62-86 yr). Specifically, participants viewed repeated sequences of six colored, fractal images and indicated whether each item was presented "in sequence" or "out of sequence." Several out of sequence probe trials were used to provide a detailed assessment of sequence memory, including: (i) repeating an item from earlier in the sequence ("Repeats"; e.g., AB A: DEF), (ii) skipping ahead in the sequence ("Skips"; e.g., AB D: DEF), and (iii) inserting an item from a different sequence into the same ordinal position ("Ordinal Transfers"; e.g., AB 3: DEF). We found that older adults performed as well as younger controls when tested on well-known and predictable sequences, but were severely impaired when tested using novel sequences. Importantly, overall sequence memory performance in older adults steadily declined with age, a decline not detected with other measures (RAVLT or BPS-O). We further characterized this deficit by showing that performance of older adults was severely impaired on specific probe trials that required detailed knowledge of the sequence (Skips and Ordinal Transfers), and was associated with a shift in their underlying mnemonic representation of the sequences. Collectively, these findings provide unambiguous evidence that the capacity to remember sequences of events is fundamentally affected by typical aging. © 2015 Allen et al.; Published by Cold Spring Harbor Laboratory Press.

Volunteering as Red Queen Mechanism for Cooperation in Public Goods Games

NASA Astrophysics Data System (ADS)

Hauert, Christoph; De Monte, Silvia; Hofbauer, Josef; Sigmund, Karl

2002-05-01

The evolution of cooperation among nonrelated individuals is one of the fundamental problems in biology and social sciences. Reciprocal altruism fails to provide a solution if interactions are not repeated often enough or groups are too large. Punishment and reward can be very effective but require that defectors can be traced and identified. Here we present a simple but effective mechanism operating under full anonymity. Optional participation can foil exploiters and overcome the social dilemma. In voluntary public goods interactions, cooperators and defectors will coexist. We show that this result holds under very diverse assumptions on population structure and adaptation mechanisms, leading usually not to an equilibrium but to an unending cycle of adjustments (a Red Queen type of evolution). Thus, voluntary participation offers an escape hatch out of some social traps. Cooperation can subsist in sizable groups even if interactions are not repeated, defectors remain anonymous, players have no memory, and assortment is purely random.

Views of South African Chemistry Students in University Bridging Programs on the Reliability of Experimental Data

NASA Astrophysics Data System (ADS)

Rollnick, Marissa; Dlamini, Betty; Lotz, Sandra; Lubben, Fred

2001-08-01

This paper reports an investigation of the status of procedural knowledge in chemistry amongst students entering into bridging programs at two South African universities. The students answered a questionnaire which investigated their perceived reasons for repeating readings and their ideas about handling data. Students also answered a question on laboratory apparatus which was used to assess their laboratory experience. The overall responses were analysed, as well as their relationship to laboratory experience and home language. The findings show that students overall tend to repeat in order to get a recurring reading. Very few students were able to use a line of best fit for a set of graphical data. There is some relationship between their responses and previous laboratory experiences, but little fundamental difference between the responses of the two main language groups. Some implications for tertiary education in chemistry are discussed.

Regression away from the mean: Theory and examples.

PubMed

Schwarz, Wolf; Reike, Dennis

2018-02-01

Using a standard repeated measures model with arbitrary true score distribution and normal error variables, we present some fundamental closed-form results which explicitly indicate the conditions under which regression effects towards (RTM) and away from the mean are expected. Specifically, we show that for skewed and bimodal distributions many or even most cases will show a regression effect that is in expectation away from the mean, or that is not just towards but actually beyond the mean. We illustrate our results in quantitative detail with typical examples from experimental and biometric applications, which exhibit a clear regression away from the mean ('egression from the mean') signature. We aim not to repeal cautionary advice against potential RTM effects, but to present a balanced view of regression effects, based on a clear identification of the conditions governing the form that regression effects take in repeated measures designs. © 2017 The British Psychological Society.

Impaired face recognition is associated with social inhibition

PubMed Central

Avery, Suzanne N; VanDerKlok, Ross M; Heckers, Stephan; Blackford, Jennifer U

2016-01-01

Face recognition is fundamental to successful social interaction. Individuals with deficits in face recognition are likely to have social functioning impairments that may lead to heightened risk for social anxiety. A critical component of social interaction is how quickly a face is learned during initial exposure to a new individual. Here, we used a novel Repeated Faces task to assess how quickly memory for faces is established. Face recognition was measured over multiple exposures in 52 young adults ranging from low to high in social inhibition, a core dimension of social anxiety. High social inhibition was associated with a smaller slope of change in recognition memory over repeated face exposure, indicating participants with higher social inhibition showed smaller improvements in recognition memory after seeing faces multiple times. We propose that impaired face learning is an important mechanism underlying social inhibition and may contribute to, or maintain, social anxiety. PMID:26776300

Impaired face recognition is associated with social inhibition.

PubMed

Avery, Suzanne N; VanDerKlok, Ross M; Heckers, Stephan; Blackford, Jennifer U

2016-02-28

Face recognition is fundamental to successful social interaction. Individuals with deficits in face recognition are likely to have social functioning impairments that may lead to heightened risk for social anxiety. A critical component of social interaction is how quickly a face is learned during initial exposure to a new individual. Here, we used a novel Repeated Faces task to assess how quickly memory for faces is established. Face recognition was measured over multiple exposures in 52 young adults ranging from low to high in social inhibition, a core dimension of social anxiety. High social inhibition was associated with a smaller slope of change in recognition memory over repeated face exposure, indicating participants with higher social inhibition showed smaller improvements in recognition memory after seeing faces multiple times. We propose that impaired face learning is an important mechanism underlying social inhibition and may contribute to, or maintain, social anxiety. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Uniquely human self-control begins at school age.

PubMed

Herrmann, Esther; Misch, Antonia; Hernandez-Lloreda, Victoria; Tomasello, Michael

2015-11-01

Human beings have remarkable skills of self-control, but the evolutionary origins of these skills are unknown. Here we compare children at 3 and 6 years of age with one of humans' two nearest relatives, chimpanzees, on a battery of reactivity and self-control tasks. Three-year-old children and chimpanzees were very similar in their abilities to resist an impulse for immediate gratification, repeat a previously successful action, attend to a distracting noise, and quit in the face of repeated failure. Six-year-old children were more skillful than either 3-year-olds or chimpanzees at controlling their impulses. These results suggest that humans' most fundamental skills of self-control - as part of the overall decision-making process - are a part of their general great ape heritage, and that their species-unique skills of self-control begin at around the age at which many children begin formal schooling. © 2014 John Wiley & Sons Ltd.

Stability of Tandem Repeats in the Drosophila Melanogaster HSR-Omega Nuclear RNA

PubMed Central

Hogan, N. C.; Slot, F.; Traverse, K. L.; Garbe, J. C.; Bendena, W. G.; Pardue, M. L.

1995-01-01

The Drosophila melanogaster Hsr-omega locus produces a nuclear RNA containing >5 kb of tandem repeat sequences. These repeats are unique to Hsr-omega and show concerted evolution similar to that seen with classical satellite DNAs. In D. melanogaster the monomer is ~280 bp. Sequences of 191/2 monomers differ by 8 +/- 5% (mean +/- SD), when all pairwise comparisons are considered. Differences are single nucleotide substitutions and 1-3 nucleotide deletions/insertions. Changes appear to be randomly distributed over the repeat unit. Outer repeats do not show the decrease in monomer homogeneity that might be expected if homogeneity is maintained by recombination. However, just outside the last complete repeat at each end, there are a few fragments of sequence similar to the monomer. The sequences in these flanking regions are not those predicted for sequences decaying in the absence of recombination. Instead, the fragmentation of the sequence homology suggests that flanking regions have undergone more severe disruptions, possibly during an insertion or amplification event. Hsr-omega alleles differing in the number of repeats are detected and appear to be stable over a few thousand generations; however, both increases and decreases in repeat numbers have been observed. The new alleles appear to be as stable as their predecessors. No alleles of less than ~5 kb nor more than ~16 kb of repeats were seen in any stocks examined. The evidence that there is a limit on the minimum number of repeats is consistent with the suggestion that these repeats are important in the function of the unusual Hsr-omega nuclear RNA. PMID:7540581

Effects of soil disturbance on the fundamental, sustainable productivity of managed forests

Treesearch

Robert F. Powers

2002-01-01

Environmental policies in the United States and abroad are reducing timber harvests while wood demand is mounting. Reduced harvesting on public lands means that privately owned lands will be managed with greater intensity in the United States and that wood will be imported from other nations lacking strong environmental safeguards. It is imperative, therefore, that...

Mapping Latin America for Grades Six to Ten. Third Edition.

ERIC Educational Resources Information Center

Stanford Univ., CA. Stanford Program on International and Cross Cultural Education.

This unit, to be used with students in grades 6-10, has been designed to serve three purposes. First, the unit acts as an introduction to, or review of, fundamental geographic concepts and vocabulary. Second, it teaches students about the basic physical and political geography of Latin America. Third, students learn to examine maps with a critical…

The National Security Strategy Under the United Nations and International Law

DTIC Science & Technology

2004-03-19

a result of that war." This was addressed in 1951 by Hans Kelsen in a legal analysis of fundamental problems with the UN Charter. He concluded that...www.zmag.org/content/print_article.cfm>; Internet; accessed 31 January 2004. 36 Charter of the United Nations, Article 107. 37 Kearly, 27–28. 38 Hans Kelsen

Mountain Plains Learning Experience Guide: Marketing. Course: Cash Register Operation.

ERIC Educational Resources Information Center

Egan, B.

One of thirteen individualized courses included in a marketing curriculum, this course is on the fundamentals of operating a cash register. The course is comprised of four units: (1) Face of Cash Register, (2) Operating a Checkout Station, (3) Checker-Cashier Qualities, and (4) NCR 250 Electronic Cash Register. Each unit begins with a Unit…

We the People: Law-Related Lessons on Teaching the Constitution.

ERIC Educational Resources Information Center

Constitutional Rights Foundation, Chicago, IL.

The Unites States Constitution and the Bill of Rights set forth the basic principles of the U.S. democratic constitutional order. It is from these documents that the fundamental political concepts of the United States are derived. The program presented here was developed for junior high school students and is intended to combat the apathy toward…

Teaching Mass Transfer and Filtration Using Crossflow Reverse Osmosis and Nanofiltration: An Experiment for the Undergraduate Unit Operations Lab

ERIC Educational Resources Information Center

Anastasio, Daniel; McCutcheon, Jeffrey

2012-01-01

A crossflow reverse osmosis (RO) system was built for a senior-level chemical engineering unit operations laboratory course. Intended to teach students mass transfer fundamentals related to membrane separations, students tested several commercial desalination membranes, measuring water flux and salt rejections at various pressures, flow rates, and…

Fundamental rate-loss trade-off for the quantum internet

NASA Astrophysics Data System (ADS)

Azuma, Koji; Mizutani, Akihiro; Lo, Hoi-Kwong

2016-11-01

The quantum internet holds promise for achieving quantum communication--such as quantum teleportation and quantum key distribution (QKD)--freely between any clients all over the globe, as well as for the simulation of the evolution of quantum many-body systems. The most primitive function of the quantum internet is to provide quantum entanglement or a secret key to two points efficiently, by using intermediate nodes connected by optical channels with each other. Here we derive a fundamental rate-loss trade-off for a quantum internet protocol, by generalizing the Takeoka-Guha-Wilde bound to be applicable to any network topology. This trade-off has essentially no scaling gap with the quantum communication efficiencies of protocols known to be indispensable to long-distance quantum communication, such as intercity QKD and quantum repeaters. Our result--putting a practical but general limitation on the quantum internet--enables us to grasp the potential of the future quantum internet.

Fundamental rate-loss trade-off for the quantum internet

PubMed Central

Azuma, Koji; Mizutani, Akihiro; Lo, Hoi-Kwong

2016-01-01

The quantum internet holds promise for achieving quantum communication—such as quantum teleportation and quantum key distribution (QKD)—freely between any clients all over the globe, as well as for the simulation of the evolution of quantum many-body systems. The most primitive function of the quantum internet is to provide quantum entanglement or a secret key to two points efficiently, by using intermediate nodes connected by optical channels with each other. Here we derive a fundamental rate-loss trade-off for a quantum internet protocol, by generalizing the Takeoka–Guha–Wilde bound to be applicable to any network topology. This trade-off has essentially no scaling gap with the quantum communication efficiencies of protocols known to be indispensable to long-distance quantum communication, such as intercity QKD and quantum repeaters. Our result—putting a practical but general limitation on the quantum internet—enables us to grasp the potential of the future quantum internet. PMID:27886172

Fundamental rate-loss trade-off for the quantum internet.

PubMed

Azuma, Koji; Mizutani, Akihiro; Lo, Hoi-Kwong

2016-11-25

The quantum internet holds promise for achieving quantum communication-such as quantum teleportation and quantum key distribution (QKD)-freely between any clients all over the globe, as well as for the simulation of the evolution of quantum many-body systems. The most primitive function of the quantum internet is to provide quantum entanglement or a secret key to two points efficiently, by using intermediate nodes connected by optical channels with each other. Here we derive a fundamental rate-loss trade-off for a quantum internet protocol, by generalizing the Takeoka-Guha-Wilde bound to be applicable to any network topology. This trade-off has essentially no scaling gap with the quantum communication efficiencies of protocols known to be indispensable to long-distance quantum communication, such as intercity QKD and quantum repeaters. Our result-putting a practical but general limitation on the quantum internet-enables us to grasp the potential of the future quantum internet.

Development of PCR-RFP and DNA barcoding plastic markers for yellow toadflax and Dalmatian toadflax

Treesearch

Andrew Boswell

2013-01-01

Yellow toadflax and Dalmatian toadflax are problematic invasive plant species in North America. Yellow toadflax was introduced multiple times to the United States from Europe, beginning in the late 1600s. Dalmatian toadflax has similarly been repeatedly introduced to the United States, starting in 1874. Both species are known to inhabit disturbed areas, competing for...

Variation: Use It or Misuse It--Replication and Its Variants

ERIC Educational Resources Information Center

Drummond, Gordon B.; Vowler, Sarah L.

2012-01-01

In this article, the authors talk about variation and how variation between measurements may be reduced if sampling is not random. They also talk about replication and its variants. A replicate is a repeated measurement from the same experimental unit. An experimental unit is the smallest part of an experiment or a study that can be subject to a…

Analytical relationships for prediction of the mechanical properties of additively manufactured porous biomaterials

PubMed Central

Hedayati, Reza

2016-01-01

Abstract Recent developments in additive manufacturing techniques have motivated an increasing number of researchers to study regular porous biomaterials that are based on repeating unit cells. The physical and mechanical properties of such porous biomaterials have therefore received increasing attention during recent years. One of the areas that have revived is analytical study of the mechanical behavior of regular porous biomaterials with the aim of deriving analytical relationships that could predict the relative density and mechanical properties of porous biomaterials, given the design and dimensions of their repeating unit cells. In this article, we review the analytical relationships that have been presented in the literature for predicting the relative density, elastic modulus, Poisson's ratio, yield stress, and buckling limit of regular porous structures based on various types of unit cells. The reviewed analytical relationships are used to compare the mechanical properties of porous biomaterials based on different types of unit cells. The major areas where the analytical relationships have improved during the recent years are discussed and suggestions are made for future research directions. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3164–3174, 2016. PMID:27502358

The incompatibility of the United Nations' goals and conventionalist ethical relativism.

PubMed

Kopelman, Loretta M

2005-09-01

The Universal Draft Declaration on Bioethics and Human Rights seeks to provide moral direction to nations and their citizens on a series of bioethical concerns. In articulating principles, it ranks respect for human rights, human dignity and fundamental freedoms ahead of respect for cultural diversity and pluralism. This ranking is controversial because it entails the rejection of the popular theory, conventionalist ethical relativism. If consistently defended, this theory also undercuts other United Nations activities that assume member states and people around the world can reach trans-cultural judgments having moral authority about health, pollution, aggression, rights, slavery, and so on. To illustrate problems with conventionalist ethical relativism and the importance of rejecting it for reasons of health, human rights, human dignity and fundamental freedoms, the widespread practice of female genital circumcision or cutting is discussed. These surgeries are virtually a test case for conventionalist ethical relativism since they are widely supported within these cultures as religious and health practices and widely condemned outside them, including by the United Nations.

Consensus and experience trump leadership, suppressing individual personality during social foraging.

PubMed

McDonald, Nicholas D; Rands, Sean A; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C

2016-09-01

Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation.

Consensus and experience trump leadership, suppressing individual personality during social foraging

PubMed Central

McDonald, Nicholas D.; Rands, Sean A.; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C.

2016-01-01

Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation. PMID:27652342

The C9orf72 repeat expansion disrupts nucleocytoplasmic transport.

PubMed

Zhang, Ke; Donnelly, Christopher J; Haeusler, Aaron R; Grima, Jonathan C; Machamer, James B; Steinwald, Peter; Daley, Elizabeth L; Miller, Sean J; Cunningham, Kathleen M; Vidensky, Svetlana; Gupta, Saksham; Thomas, Michael A; Hong, Ingie; Chiu, Shu-Ling; Huganir, Richard L; Ostrow, Lyle W; Matunis, Michael J; Wang, Jiou; Sattler, Rita; Lloyd, Thomas E; Rothstein, Jeffrey D

2015-09-03

The hexanucleotide repeat expansion (HRE) GGGGCC (G4C2) in C9orf72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recent studies support an HRE RNA gain-of-function mechanism of neurotoxicity, and we previously identified protein interactors for the G4C2 RNA including RanGAP1. A candidate-based genetic screen in Drosophila expressing 30 G4C2 repeats identified RanGAP (Drosophila orthologue of human RanGAP1), a key regulator of nucleocytoplasmic transport, as a potent suppressor of neurodegeneration. Enhancing nuclear import or suppressing nuclear export of proteins also suppresses neurodegeneration. RanGAP physically interacts with HRE RNA and is mislocalized in HRE-expressing flies, neurons from C9orf72 ALS patient-derived induced pluripotent stem cells (iPSC-derived neurons), and in C9orf72 ALS patient brain tissue. Nuclear import is impaired as a result of HRE expression in the fly model and in C9orf72 iPSC-derived neurons, and these deficits are rescued by small molecules and antisense oligonucleotides targeting the HRE G-quadruplexes. Nucleocytoplasmic transport defects may be a fundamental pathway for ALS and FTD that is amenable to pharmacotherapeutic intervention.

Contour-Based Corner Detection and Classification by Using Mean Projection Transform

PubMed Central

Kahaki, Seyed Mostafa Mousavi; Nordin, Md Jan; Ashtari, Amir Hossein

2014-01-01

Image corner detection is a fundamental task in computer vision. Many applications require reliable detectors to accurately detect corner points, commonly achieved by using image contour information. The curvature definition is sensitive to local variation and edge aliasing, and available smoothing methods are not sufficient to address these problems properly. Hence, we propose Mean Projection Transform (MPT) as a corner classifier and parabolic fit approximation to form a robust detector. The first step is to extract corner candidates using MPT based on the integral properties of the local contours in both the horizontal and vertical directions. Then, an approximation of the parabolic fit is calculated to localize the candidate corner points. The proposed method presents fewer false-positive (FP) and false-negative (FN) points compared with recent standard corner detection techniques, especially in comparison with curvature scale space (CSS) methods. Moreover, a new evaluation metric, called accuracy of repeatability (AR), is introduced. AR combines repeatability and the localization error (Le) for finding the probability of correct detection in the target image. The output results exhibit better repeatability, localization, and AR for the detected points compared with the criteria in original and transformed images. PMID:24590354

Mature clustered, regularly interspaced, short palindromic repeats RNA (crRNA) length is measured by a ruler mechanism anchored at the precursor processing site.

PubMed

Hatoum-Aslan, Asma; Maniv, Inbal; Marraffini, Luciano A

2011-12-27

Precise RNA processing is fundamental to all small RNA-mediated interference pathways. In prokaryotes, clustered, regularly interspaced, short palindromic repeats (CRISPR) loci encode small CRISPR RNAs (crRNAs) that protect against invasive genetic elements by antisense targeting. CRISPR loci are transcribed as a long precursor that is cleaved within repeat sequences by CRISPR-associated (Cas) proteins. In many organisms, this primary processing generates crRNA intermediates that are subject to additional nucleolytic trimming to render mature crRNAs of specific lengths. The molecular mechanisms underlying this maturation event remain poorly understood. Here, we defined the genetic requirements for crRNA primary processing and maturation in Staphylococcus epidermidis. We show that changes in the position of the primary processing site result in extended or diminished maturation to generate mature crRNAs of constant length. These results indicate that crRNA maturation occurs by a ruler mechanism anchored at the primary processing site. We also show that maturation is mediated by specific cas genes distinct from those genes involved in primary processing, showing that this event is directed by CRISPR/Cas loci.

Contour-based corner detection and classification by using mean projection transform.

PubMed

Kahaki, Seyed Mostafa Mousavi; Nordin, Md Jan; Ashtari, Amir Hossein

2014-02-28

Image corner detection is a fundamental task in computer vision. Many applications require reliable detectors to accurately detect corner points, commonly achieved by using image contour information. The curvature definition is sensitive to local variation and edge aliasing, and available smoothing methods are not sufficient to address these problems properly. Hence, we propose Mean Projection Transform (MPT) as a corner classifier and parabolic fit approximation to form a robust detector. The first step is to extract corner candidates using MPT based on the integral properties of the local contours in both the horizontal and vertical directions. Then, an approximation of the parabolic fit is calculated to localize the candidate corner points. The proposed method presents fewer false-positive (FP) and false-negative (FN) points compared with recent standard corner detection techniques, especially in comparison with curvature scale space (CSS) methods. Moreover, a new evaluation metric, called accuracy of repeatability (AR), is introduced. AR combines repeatability and the localization error (Le) for finding the probability of correct detection in the target image. The output results exhibit better repeatability, localization, and AR for the detected points compared with the criteria in original and transformed images.

You Are What You Eat

MedlinePlus

... contents. Back to Top Sugars In chemistry, a polymer is a substance that contains repeating units: Polyester and many plastics are examples of synthetic polymers. Proteins, nucleic acids and carbohydrates are natural "biopolymers" ...

Evolution of Time Scales

DTIC Science & Technology

2006-12-01

as the fundamental unit of time in the International System of Units. It was defined as ( Metrologia , 1968) “the duration of 9 192 631 770 periods of...atomic time equivalent to the second of ET in principle. The Comité Consultatif pour la Définition de la Seconde (CCDS) of the CIPM recommended...with the definition of the second, the unit of time of the Inter- national System of Units” ( Metrologia , 1971). The CCDS (BIPM Com. Cons. Déf. Seconde

The Scales of Time, Length, Mass, Energy, and Other Fundamental Physical Quantities in the Atomic World and the Use of Atomic Units in Quantum Mechanical Calculations

ERIC Educational Resources Information Center

Teo, Boon K.; Li, Wai-Kee

2011-01-01

This article is divided into two parts. In the first part, the atomic unit (au) system is introduced and the scales of time, space (length), and speed, as well as those of mass and energy, in the atomic world are discussed. In the second part, the utility of atomic units in quantum mechanical and spectroscopic calculations is illustrated with…

Ventilation-Perfusion Relationships Following Experimental Pulmonary Contusion

DTIC Science & Technology

2007-06-14

696.7 6.1 to 565.0 24.3 Hounsfield units ), as did VOL (4.3 0.5 to 33.5 3.2%). Multivariate linear regression of MGSD, VOL, VD/VT, and QS vs. PaO2...parenchyma was separated into four regions based on the Hounsfield unit (HU) ranges reported by Gattinoni et al. (23) via a segmentation process executed...determined by repeated measures ANOVA. CT, computed tomography; MGSD, mean gray-scale density of the entire lung by CT scan; HU, Hounsfield units

Structural elucidation of the Brucella melitensis M antigen by high-resolution NMR at 500 MHz

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

Bundle, D.R.; Cherwonogrodzky, J.W.; Perry, M.B.

The Brucella M antigen from the species type strain Brucella melitensis 16M has been identified as a component of the cell wall lipopolysaccharide (LPS). O polysaccharide liberated from this LPS by mild acid hydrolysis exhibited M activity in serological tests and was shown to be a homopolymer of 4-formamido-4,6-dideoxy-..cap alpha..-D-mannopyranosyl residues arranged in an oligosaccharide repeating unit as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the native lipopolysaccharide. Structural analysis of the O polysaccharide by NMR methods was difficult due to apparent microheterogeneity of the repeating unit, which was in fact caused by the presence of rotational isomers ofmore » the N-formyl moiety. This problem was resolved by chemical modification of the polysaccharide to its amino and N-acetyl derivatives, the 500-MHz /sup 1/H and 125-MHz /sup 13/C NMR spectra of which could be analyzed in terms of a unique structure through application of pH-dependent ..beta..-shifts and two-dimensional techniques that included COSY, relayed COSY, and NOESY experiments together with heteronuclear C/H shift correlation spectroscopy. On the basis of these experiments and supported by methylation and periodate oxidation data, the structure of the M polysaccharide was determined as a linear polymer of unbranched pentasaccharide repeating units consisting of four 1,2-linked and one 1,3-lined 4,6-dideoxy-4-formamido-..cap alpha..-D-mannopyranosyl residues. The marked structural similarity of the M antigen and the A antigen, which is known to be a 1,2-linked homopolysaccharide of 4,6-dideoxy-4-formamido-..cap alpha..-D-mannopyranosyl units, accounts for cross-serological reactions of the two and the long-standing confusion surrounding the nature of their antigenic determinants.« less

A comparison of recordings of sentences and spontaneous speech: perceptual and acoustic measures in preschool children's voices.

PubMed

McAllister, Anita; Brandt, Signe Kofoed

2012-09-01

A well-controlled recording in a studio is fundamental in most voice rehabilitation. However, this laboratory like recording method has been questioned because voice use in a natural environment may be quite different. In children's natural environment, high background noise levels are common and are an important factor contributing to voice problems. The primary noise source in day-care centers is the children themselves. The aim of the present study was to compare perceptual evaluations of voice quality and acoustic measures from a controlled recording with recordings of spontaneous speech in children's natural environment in a day-care setting. Eleven 5-year-old children were recorded three times during a day at the day care. The controlled speech material consisted of repeated sentences. Matching sentences were selected from the spontaneous speech. All sentences were repeated three times. Recordings were randomized and analyzed acoustically and perceptually. Statistic analyses showed that fundamental frequency was significantly higher in spontaneous speech (P<0.01) as was hyperfunction (P<0.001). The only characteristic the controlled sentences shared with spontaneous speech was degree of hoarseness (Spearman's rho=0.564). When data for boys and girls were analyzed separately, a correlation was found for the parameter breathiness (rho=0.551) for boys, and for girls the correlation for hoarseness remained (rho=0.752). Regarding acoustic data, none of the measures correlated across recording conditions for the whole group. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Characterization of a tandemly repeated DNA sequence family originally derived by retroposition of tRNA(Glu) in the newt.

PubMed

Nagahashi, S; Endoh, H; Suzuki, Y; Okada, N

1991-11-20

A previous report from this laboratory showed that in vitro transcription of total genomic DNA of the newt Cynopus pyrrhogaster resulted in a discrete sized 8 S RNA, which represented highly repetitive and transcribable sequences with a glutamic acid tRNA-like structure in the newt genome. We isolated four independent clones from a newt genomic library and determined the complete sequences of three 2000 to 2400 base-pair PstI fragments spanning the 8 S RNA gene. The glutamic acid tRNA-related segment in the 8 S RNA gene contains the CCA sequence expected as the 3' terminus of a tRNA molecule. Further, the 11 nucleotides located 13 nucleotides upstream from one of the two transcription initiation sites of the 8 S RNA were found to be repeated in the region upstream from the termination site, suggesting that the original unit, which is shorter than the 8 S RNA, was retrotransposed via cDNA intermediates from the PolIII transcript. In the upstream region of the 8 S RNA gene, a 360 nucleotide unit containing the glutamic acid tRNA-related segment was found to be duplicated (clones NE1 and NE10) or triplicated (clone NE3). Except for the difference in the number of the 360 nucleotide unit, the three sequences of the 2000 to 2400 base-pair PstI fragment were essentially the same with only a few mutations and minor deletions. Inverse polymerase chain reaction and sequence determination of the products, together with a Southern hybridization experiment, demonstrated that the family consists of a tandemly repeated unit of 3300, 3700 or 4100 base-pairs. Thus during evolution, this family in the newt was created by retroposition via cDNA intermediates, followed by duplication or triplication of the 360 nucleotide unit and multiplication of the 3300 to 4100 base-pair region at the DNA level.

Using Remotely Sensed Data to Automate and Improve Census Bureau Update Activities

NASA Astrophysics Data System (ADS)

Desch, A., IV

2017-12-01

Location of established and new housing structures is fundamental in the Census Bureau's planning and execution of each decennial census. Past Census address list compilation and update programs have involved sending more than 100,000 workers into the field to find and verify housing units. The 2020 Census program has introduced an imagery based In-Office Address Canvassing Interactive Review (IOAC-IR) program in an attempt to reduce the in-field workload. The human analyst driven, aerial image based IOAC-IR operation has proven to be a cost effective and accurate substitute for a large portion of the expensive in-field address canvassing operations. However, the IOAC-IR still required more than a year to complete and over 100 full-time dedicated employees. Much of the basic image analysis work done in IOAC-IR can be handled with established remote sensing and computer vision techniques. The experience gained from the Interactive Review phase of In-Office Address Canvassing has led to the development of a prototype geo-processing tool to automate much of this process for future and ongoing Address Canvassing operations. This prototype utilizes high-resolution aerial imagery and LiDAR to identify structures and compare their location to existing Census geographic information. In this presentation, we report on the comparison of this exploratory system's results to the human based IOAC-IR. The experimental image and LiDAR based change detection approach has itself led to very promising follow-on experiments utilizing very current, high repeat datasets and scalable cloud computing. We will discuss how these new techniques can be used to both aid the US Census Bureau meet its goals of identify all the housing units in the US as well as aid developing countries better identify where there population is currently distributed.

Research on control technology of hardware parallelism for marine controlled source electromagnetic transmitter

NASA Astrophysics Data System (ADS)

Wang, Meng; Deng, Ming; Luo, Xianhu; Zhao, Qingxian; Chen, Kai; Jing, Jianen

2018-02-01

The marine controlled source electromagnetic (CSEM) method has been recognized as an effective exploration method of shallow hydrocarbons around the world. We developed our own underwater marine CSEM transmitter that consisted of many functional modules with various response times. We previously adopted a centralized software-control technology to design the transmitter circuit topological structure. That structure probably generated a control disorder or malfunction. These undesirable conditions could lead to repeated recovery and deployment of the transmitter, which not only consumed time but also affected data continuity and establishment of stable and continuous CSEM field. We developed an instrument design concept named ‘control technology of hardware parallelism’. In this design, a noteworthy innovation of our new technology is to solve the above-mentioned problems at the physical and fundamental levels. We used several self-contained control-units to simultaneously accomplish the predetermined functions of the transmitter. The new solution relies on two technologies: multi-core embedded technology and multi-channel parallel optical-fiber data transmission technology. The first technology depends on many independent microcontrollers. Every microcontroller is only used to achieve a customized function. The second one relies on several multiple optical-fiber transmission channels realized by a complex programmable logic device and two optical-fiber conversion devices, which are used to establish a communication link between the shipboard monitoring and control-unit and underwater transmitter. We have conducted some marine experiments to verify the reliability and stability of the new method. In particular, the new technology used in the transmitter system could help us obtain more useful measured data in a limited time, improve real-time efficiency, and support the establishment of a stable CSEM field.

Mechanistic Insights into Ring Cleavage and Contraction of Benzene over a Titanium Hydride Cluster.

PubMed

Kang, Xiaohui; Luo, Gen; Luo, Lun; Hu, Shaowei; Luo, Yi; Hou, Zhaomin

2016-09-14

Carbon-carbon bond cleavage of benzene by transition metals is of great fundamental interest and practical importance, as this transformation is involved in the production of fuels and other important chemicals in the industrial hydrocracking of naphtha on solid catalysts. Although this transformation is thought to rely on cooperation of multiple metal sites, molecular-level information on the reaction mechanism has remained scarce to date. Here, we report the DFT studies of the ring cleavage and contraction of benzene by a molecular trinuclear titanium hydride cluster. Our studies suggest that the reaction is initiated by benzene coordination, followed by H2 release, C6H6 hydrometalation, repeated C-C and C-H bond cleavage and formation to give a MeC5H4 unit, and insertion of a Ti atom into the MeC5H4 unit with release of H2 to give a metallacycle product. The C-C bond cleavage and ring contraction of toluene can also occur in a similar fashion, though some details are different due to the presence of the methyl substituent. Obviously, the facile release of H2 from the metal hydride cluster to provide electrons and to alter the charge population at the metal centers, in combination with the flexible metal-hydride connections and dynamic redox behavior of the trimetallic framework, has enabled this unusual transformation to occur. This work has not only provided unprecedented insights into the activation and transformation of benzene over a multimetallic framework but it may also offer help in the design of new molecular catalysts for the activation and transformation of inactive aromatics.

Heterogeneic dynamics of the structures of multiple gene clusters in two pathogenetically different lines originating from the same phytoplasma.

PubMed

Arashida, Ryo; Kakizawa, Shigeyuki; Hoshi, Ayaka; Ishii, Yoshiko; Jung, Hee-Young; Kagiwada, Satoshi; Yamaji, Yasuyuki; Oshima, Kenro; Namba, Shigetou

2008-04-01

Phytoplasmas are phloem-limited plant pathogens that are transmitted by insect vectors and are associated with diseases in hundreds of plant species. Despite their small sizes, phytoplasma genomes have repeat-rich sequences, which are due to several genes that are encoded as multiple copies. These multiple genes exist in a gene cluster, the potential mobile unit (PMU). PMUs are present at several distinct regions in the phytoplasma genome. The multicopy genes encoded by PMUs (herein named mobile unit genes [MUGs]) and similar genes elsewhere in the genome (herein named fundamental genes [FUGs]) are likely to have the same function based on their annotations. In this manuscript we show evidence that MUGs and FUGs do not cluster together within the same clade. Each MUG is in a cluster with a short branch length, suggesting that MUGs are recently diverged paralogs, whereas the origin of FUGs is different from that of MUGs. We also compared the genome structures around the lplA gene in two derivative lines of the 'Candidatus Phytoplasma asteris' OY strain, the severe-symptom line W (OY-W) and the mild-symptom line M (OY-M). The gene organizations of the nucleotide sequences upstream of the lplA genes of OY-W and OY-M were dramatically different. The tra5 insertion sequence, an element of PMUs, was found only in this region in OY-W. These results suggest that transposition of entire PMUs and PMU sections has occurred frequently in the OY phytoplasma genome. The difference in the pathogenicities of OY-W and OY-M might be caused by the duplication and transposition of PMUs, followed by genome rearrangement.

Construction and sequence sampling of deep-coverage, large-insert BAC libraries for three model lepidopteran species

PubMed Central

Wu, Chengcang; Proestou, Dina; Carter, Dorothy; Nicholson, Erica; Santos, Filippe; Zhao, Shaying; Zhang, Hong-Bin; Goldsmith, Marian R

2009-01-01

Background Manduca sexta, Heliothis virescens, and Heliconius erato represent three widely-used insect model species for genomic and fundamental studies in Lepidoptera. Large-insert BAC libraries of these insects are critical resources for many molecular studies, including physical mapping and genome sequencing, but not available to date. Results We report the construction and characterization of six large-insert BAC libraries for the three species and sampling sequence analysis of the genomes. The six BAC libraries were constructed with two restriction enzymes, two libraries for each species, and each has an average clone insert size ranging from 152–175 kb. We estimated that the genome coverage of each library ranged from 6–9 ×, with the two combined libraries of each species being equivalent to 13.0–16.3 × haploid genomes. The genome coverage, quality and utility of the libraries were further confirmed by library screening using 6~8 putative single-copy probes. To provide a first glimpse into these genomes, we sequenced and analyzed the BAC ends of ~200 clones randomly selected from the libraries of each species. The data revealed that the genomes are AT-rich, contain relatively small fractions of repeat elements with a majority belonging to the category of low complexity repeats, and are more abundant in retro-elements than DNA transposons. Among the species, the H. erato genome is somewhat more abundant in repeat elements and simple repeats than those of M. sexta and H. virescens. The BLAST analysis of the BAC end sequences suggested that the evolution of the three genomes is widely varied, with the genome of H. virescens being the most conserved as a typical lepidopteran, whereas both genomes of H. erato and M. sexta appear to have evolved significantly, resulting in a higher level of species- or evolutionary lineage-specific sequences. Conclusion The high-quality and large-insert BAC libraries of the insects, together with the identified BACs containing genes of interest, provide valuable information, resources and tools for comprehensive understanding and studies of the insect genomes and for addressing many fundamental questions in Lepidoptera. The sample of the genomic sequences provides the first insight into the constitution and evolution of the insect genomes. PMID:19558662

Lipase polystyrene giant amphiphiles.

PubMed

Velonia, Kelly; Rowan, Alan E; Nolte, Roeland J M

2002-04-24

A new type of giant amphiphilic molecule has been synthesized by covalently connecting a lipase enzyme headgroup to a maleimide-functionalized polystyrene tail (40 repeat units). The resulting biohybrid forms catalytic micellar rods in water.

United States Air Force Summer Faculty Research Program (1984). Program Management Report. Volume 3

DTIC Science & Technology

1984-12-01

Database Design 蕄 Raman Spectroscopy of Dr. Boake L. Plessy Glycosaminoglycans from -* Bovine Cornea 117 Study of Control Mixer Concept Dr. Kuldip S...simultaneously in polarized and non -polarized controls were repeated three times at 260-64, 368-70, 604-8-13, 735-7-40, 1277-80, 1760, 1775, and 1820 or four...times at S240-2-4, 1020 and 1874-8-90. Pooling replicates from the non -polarized components, six controls and two cAMP treatments, events repeating

De novo identification of highly diverged protein repeats by probabilistic consistency.

PubMed

Biegert, A; Söding, J

2008-03-15

An estimated 25% of all eukaryotic proteins contain repeats, which underlines the importance of duplication for evolving new protein functions. Internal repeats often correspond to structural or functional units in proteins. Methods capable of identifying diverged repeated segments or domains at the sequence level can therefore assist in predicting domain structures, inferring hypotheses about function and mechanism, and investigating the evolution of proteins from smaller fragments. We present HHrepID, a method for the de novo identification of repeats in protein sequences. It is able to detect the sequence signature of structural repeats in many proteins that have not yet been known to possess internal sequence symmetry, such as outer membrane beta-barrels. HHrepID uses HMM-HMM comparison to exploit evolutionary information in the form of multiple sequence alignments of homologs. In contrast to a previous method, the new method (1) generates a multiple alignment of repeats; (2) utilizes the transitive nature of homology through a novel merging procedure with fully probabilistic treatment of alignments; (3) improves alignment quality through an algorithm that maximizes the expected accuracy; (4) is able to identify different kinds of repeats within complex architectures by a probabilistic domain boundary detection method and (5) improves sensitivity through a new approach to assess statistical significance. Server: http://toolkit.tuebingen.mpg.de/hhrepid; Executables: ftp://ftp.tuebingen.mpg.de/pub/protevo/HHrepID

The disorder-specific psychological impairment in complex PTSD: A flawed working model for restoration of trust.

PubMed

Laddis, Andreas

2018-03-22

This article methodically gathers concepts and findings from related disciplines to propose that there is a fundamental, disorder-specific psychological impairment, which defines Complex Posttraumatic Stress Disorder (PTSD) as etiologically different from simple PTSD. This impairment is a flawed working model for restoration of trust when one partner fears betrayal. This working model is legacy of childhood relationships with manipulative caretakers who kept the child powerless to test the trustworthiness of their reasons to break promises and to fail the child's expectations. Manipulative caretakers invert the respective roles and responsibilities for restoration of trust, which constitutes perversion of intimacy. This article describes how that fundamental flaw becomes the cause of patients' disorder, by episodically rendering them powerless to ascertain a perception of grave betrayal as true or false in later relationships. Repeated failure with experiments for certainty about others' love explains the characteristic personality traits and beliefs of persons with Complex PTSD, i.e., cynicism about the world's benevolence, self-derogation and sense of a foreshortened future. This article closes with reference to a study that investigated the efficacy of a crisis intervention designed to remediate this fundamental impairment.

Detecting vocal fatigue in student singers using acoustic measures of mean fundamental frequency, jitter, shimmer, and harmonics-to-noise ratio

NASA Astrophysics Data System (ADS)

Sisakun, Siphan

2000-12-01

The purpose of this study is to explore the ability of four acoustic parameters, mean fundamental frequency, jitter, shimmer, and harmonics-to-noise ratio, to detect vocal fatigue in student singers. The participants are 15 voice students, who perform two distinct tasks, data collection task and vocal fatiguing task. The data collection task includes the sustained vowel /a/, reading a standard passage, and self-rate on a vocal fatigue form. The vocal fatiguing task is the vocal practice of musical scores for a total of 45 minutes. The four acoustic parameters are extracted using the software EZVoicePlus. The data analyses are performed to answer eight research questions. The first four questions relate to correlations of the self-rating scale and each of the four parameters. The next four research questions relate to differences in the parameters over time using one-factor repeated measures analysis of variance (ANOVA). The result yields a proposed acoustic profile of vocal fatigue in student singers. This profile is characterized by increased fundamental frequency; slightly decreased jitter; slightly decreased shimmer; and slightly increased harmonics-to-noise ratio. The proposed profile requires further investigation.

Divergence in centromere structure distinguishes related genomes in Coix lacryma-jobi and its wild relative.

PubMed

Han, Yonghua; Wang, Guixiang; Liu, Zhao; Liu, Jinhua; Yue, Wei; Song, Rentao; Zhang, Xueyong; Jin, Weiwei

2010-02-01

Knowledge about the composition and structure of centromeres is critical for understanding how centromeres perform their functional roles. Here, we report the sequences of one centromere-associated bacterial artificial chromosome clone from a Coix lacryma-jobi library. Two Ty3/gypsy-class retrotransposons, centromeric retrotransposon of C. lacryma-jobi (CRC) and peri-centromeric retrotransposon of C. lacryma-jobi, and a (peri)centromere-specific tandem repeat with a unit length of 153 bp were identified. The CRC is highly homologous to centromere-specific retrotransposons reported in grass species. An 80-bp DNA region in the 153-bp satellite repeat was found to be conserved to centromeric satellite repeats from maize, rice, and pearl millet. Fluorescence in situ hybridization showed that the three repetitive sequences were located in (peri-)centromeric regions of both C. lacryma-jobi and Coix aquatica. However, the 153-bp satellite repeat was only detected on 20 out of the 30 chromosomes in C. aquatica. Immunostaining with an antibody against rice CENH3 indicates that the 153-bp satellite repeat and CRC might be both the major components for functional centromeres, but not all the 153-bp satellite repeats or CRC sequences are associated with CENH3. The evolution of centromeric repeats of C. lacryma-jobi during the polyploidization was discussed.

Tracking Helicopters with a Seismic Array

NASA Astrophysics Data System (ADS)

Eibl, Eva P. S.; Lokmer, Ivan; Bean, Christopher J.; Akerlie, Eggert

2015-04-01

We observed that the pressure or acoustic wave created by the rotor blades of a helicopter can couple to the ground even at 30 km distance where it creates a signal strong enough to be detected by a seismometer. The signal is harmonic tremor with a fundamental frequency downgliding with the inflection point at e.g. 14 Hz and two equally spaced overtones up to the Nyquist frequency of 50 Hz. No difference in the amplitudes between the fundamental frequency and higher harmonics was observed. Such a signature is a consequence of the regularly repeating pressure pulses generated by the helicopter's rotor blades. The signal was recorded by a seven station broadband array with an aperture of 1.6 km. Our spacing is close enough to record the signal at all stations and far enough to observe traveltime differences. The separation of the spectral lines corresponds to the time interval between the repeating sources. The highlighted harmonics contain information about the spectral content of the single source as our signal corresponds to the convolution of an infinite comb function and a single pulse. As we see all harmonics and they have the same amplitude up to the Nyquist frequency we can deduce that the frequency content of the single pulse is flat i.e. it is effectively a delta function up to the Nyquist frequency. We perform a detailed spectral and location analysis of the signal, and compare our results with the known information on the helicopter's speed, location, the frequency of the blades rotation and the amount of blades. This analysis is based on the characteristic shape of the curve i.e. speed of the gliding, minimum and maximum fundamental frequency, amplitudes at the inflection points at different stations and traveltimes deduced from the inflection points at different stations. This observation has an educative value, because the same principle could be used for the analysis of the volcanic harmonic tremor. Harmonic volcanic tremor usually has fundamental frequencies below 10 Hz but frequency downgliding and upgliding up to 30 Hz was observed e.g. on Redoubt volcano. Due to the characteristic shape of the helicopter signal it is nevertheless rather unlikely that this signal is mistaken for volcanic tremor. The helicopter gives us a robust way of testing the method and possible application of the method to volcanic harmonic tremor.

Androgen receptor polyglutamine repeat length affects receptor activity and C2C12 cell development.

PubMed

Sheppard, Ryan L; Spangenburg, Espen E; Chin, Eva R; Roth, Stephen M

2011-10-20

Testosterone (T) has an anabolic effect on skeletal muscle and is believed to exert its local effects via the androgen receptor (AR). The AR harbors a polymorphic stretch of glutamine repeats demonstrated to inversely affect receptor transcriptional activity in prostate and kidney cells. The effects of AR glutamine repeat length on skeletal muscle are unknown. In this study we examined the effect of AR CAG repeat length on AR function in C2C12 cells. AR expression vectors harboring 14, 24, and 33 CAG repeats were used to assess AR transcriptional activity. C2C12 cell proliferation, differentiation, gene expression, myotube formation, and myonuclear fusion index were assessed. Transcriptional activity increased with increasing repeat length and in response to testosterone (AR14 = 3.91 ± 0.26, AR24 = 25.21 ± 1.72, AR33 = 36.08 ± 3.22 relative light units; P < 0.001). Ligand activation was increased for AR33 (2.10 ± 0.04) compared with AR14 (1.54 ± 0.09) and AR24 (1.57 ± 0.05, P < 0.001). AR mRNA expression was elevated in each stably transfected line. AR33 cell proliferation (20,512.3 ± 1,024.0) was decreased vs. AR14 (27,604.17 ± 1,425.3; P < 0.001) after 72 h. Decreased CK activity in AR14 cells (54.9 ± 2.9 units/μg protein) in comparison to AR33 (70.8 ± 8.1) (P < 0.05) was noted. The myonuclear fusion index was lower for AR14 (15.21 ± 3.24%) and AR33 (9.97 ± 3.14%) in comparison to WT (35.07 ± 5.60%, P < 0.001). AR14 and AR33 cells also displayed atypical myotube morphology. RT-PCR revealed genotype differences in myostatin and myogenin expression. We conclude that AR polyglutamine repeat length is directly associated with transcriptional activity and alters the growth and development of C2C12 cells. This polymorphism may contribute to the heritability of muscle mass in humans.

Fluorinated monomers useful for preparing fluorinated polyquinoline polymers

NASA Technical Reports Server (NTRS)

Hendricks, Neil H. (Inventor)

1994-01-01

A new class of polymers is provided, as well as the monomers used for their preparation. The polymers provided in accordance with practice of the present invention include repeating units comprising one or more quinoline groups, wherein at least a portion of the repeating units includes a hexafluoroisopropylidene (6F) group or a 1-aryl-2,2,2-trifluoroethylidene (3F) group, or both. The hexafluoroisopropylidene group is referred to herein as a 6F group and has the following structure: ##STR1## The 6F group includes a tetravalent carbon atom bound to two trifluoromethyl moieties, with its other two bonds forming linkages in the polymer chain. The 1-aryl-2,2,2-trifluoroethylidene group is referred to herein as a 3F group and has the following structure: ##STR2## wherein Ar' is an aryl group.

[Structural organization of 5S ribosomal DNA of Rosa rugosa].

PubMed

Tynkevych, Iu O; Volkov, R A

2014-01-01

In order to clarify molecular organization of the genomic region encoding 5S rRNA in diploid species Rosa rugosa several 5S rDNA repeated units were cloned and sequenced. Analysis of the obtained sequences revealed that only one length variant of 5S rDNA repeated units, which contains intact promoter elements in the intergenic spacer region (IGS) and appears to be transcriptionally active is present in the genome. Additionally, a limited number of 5S rDNA pseudogenes lacking a portion of coding sequence and the complete IGS was detected. A high level of sequence similarity (from 93.7 to 97.5%) between the IGS of major 5S rDNA variants of East Asian R. rugosa and North American R. nitida was found indicating comparatively recent divergence of these species.

Polymer Brushes Containing Sulfonated Sugar Repeat Units: Synthesis, Characterization and In Vitro Testing of Blood Coagulation Activation

PubMed Central

Ayres, N.; Holt, D. J.; Jones, C.F.; Corum, L. E.; Grainger, D. W.

2009-01-01

A new polymer brush chemistry containing sulfonated carbohydrate repeat units has been synthesized from silicon substrates using ATRP methods and characterized both in bulk and using surface analysis. The polymer brush was designed to act as a mimic for the naturally occurring sulfonated glycosaminoglycan, heparin, commonly used for modifying blood-contacting surfaces both in vitro and in vivo. Surface analysis showed conversion of brush saccharide precursor chemistry to the desired sulfonated polymer product. The sulfonated polymer brush surface was further analyzed using three conventional in vitro tests for blood compatibility -- plasma recalcification times, complement activation, and thrombin generation. The sulfonated polymer brush films on silicon oxide wafers exhibited better assay performance in these blood component assays than the unsulfonated sugar functionalized polymer brush in all tests performed. PMID:19859552

Molecular Structure Controlled Transitions between Free-Charge Generation and Trap Formation in a Conjugated Copolymer Series

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

Pandit, Bill; Jackson, Nicholas E.; Zheng, Tianyue

2016-03-03

Charge transfer copolymers, where each repeating unit has at least one “donor” and one “acceptor” block, have played important roles in recent advances in organic photovoltaic (OPV) devices, however design criteria for these materials are still not completely clear. Here we show that the well-recognized LUMO-LUMO energy off-set design criterion for OPV materials using a fullerene acceptor is challenged in a series of copolymers, PTRn (n = 3, 5, 7 and 9), where n is the number of fused aromatic rings in the “donor” block and thienothiophene is the “acceptor” block in each repeating unit. Photoexcitation dynamics of PTRn copolymersmore » in solution and BHJ (bulk heterojunction) films demonstrated that local push-pull interactions between the “donor” block and the “acceptor” block weakens with increasing n, whereas the LUMO-LUMO off-set between the polymer and PC71BM (Phenyl-C71-butyric acid methyl ester) increases. Such a counter intuitive trend can be explained by local energetics of each repeating unit as a function of n. The energetic changes transform the copolymer with strong local charge transfer character for efficient hole-electron separation to localized hole-electron pairs with low mobility, despite the apparent increase of the polymer/PC71BM LUMO-LUMO off-set. This suggests the importance of local charge transfer character in these copolymers in the initial exciton splitting dynamics, which could ultimately be reflected in the device performance.« less

The influence of polymer architecture on the assembly of poly(ethylene oxide) grafted C60 fullerene clusters in aqueous solution: a molecular dynamics simulation study.

PubMed

Hooper, Justin B; Bedrov, Dmitry; Smith, Grant D

2009-03-28

The effect of polymer architecture on the aggregation behavior of C60 fullerenes tethered with a single chain of poly(ethylene oxide) (PEO) in aqueous solution has been investigated using coarse-grained, implicit solvent molecular dynamics simulations. The PEO-grafted fullerenes were comprised of a single tether of 60 repeat units represented as a linear polymer, a three-arm star (20 repeat units/arm) or a six-arm star (10 repeat units/arm). Additionally, the influence of arm length on self-assembly of the PEO-fullerene conjugates was investigated for the three-arm stars. Self-assembly is driven by favorable fullerene-fullerene and fullerene-PEO interactions. Our simulations reveal that it should be possible to control the size and geometry of the self-assembled fullerene aggregates in water through variation of PEO architecture and PEO molecular weight. We found that aggregate size and shape could be understood qualitatively in terms of the packing parameter concept that has been employed for diblock polymer and surfactant self-assembly. Higher molecular weight PEO (longer arms) and more compact PEO (more arms for the same molecular weight) resulted in greater steric repulsion between fullerenes, engendering greater aggregate surface curvature and hence the formation of smaller, more spherically shaped aggregates. Finally, weak attractive interactions between PEO and the fullerenes were found to play an important role in determining aggregate shape, size and the dynamics of self-assembly.

Vibrational spectroscopic study of cationic phosphorus dendrimers with aminoethylpiperidine terminal groups

NASA Astrophysics Data System (ADS)

Furer, V. L.; Vandyukov, A. E.; Tripathi, V.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

2018-04-01

Two generations of phosphoric dendrimers with piperidine functional groups were synthesized for use in biology and medicine. Neutral samples are soluble in organic solvents but after protonation these dendrimers become water soluble and can be used for biological experiments. The FTIR and FT Raman spectra of two generations of dendrimers Gi constructed from the cyclotriphosphazene core, repeating units sbnd Osbnd C6H4sbnd CHdbnd Nsbnd N(CH3)sbnd P(S)< and aminoethylpiperidine end groups sbnd NHsbnd (CH2)2sbnd C5NH11 were recorded. The study of the IR spectra shows that the NH groups form hydrogen bonds. The calculation of the molecular structure and vibrational spectra of the first generation dendrimer was performed by the method of DFT. This molecule has flat, repeating units and a plane of symmetry passing through the core. The calculation of the distribution of potential energy made it possible to classify the bands in the experimental spectra of dendrimers. Amine groups are manifested in the form of a band of NH stretching vibrations at 3389 cm-1 in the IR spectrum of G1. NH+ stretching bands located at 2646 and 2540 cm-1 in the IR spectrum of G2. The stretching vibrations of NH+ groups are noticeably shifted to low frequencies due to the formation of a hydrogen bond with the chlorine atom. The line at 1575 cm-1 in the Raman spectrum of G1 is characteristic for repeating units.

The Bill of Rights: A Law-Related Curriculum for Primary Students (Teacher's Guide and Student Materials).

ERIC Educational Resources Information Center

Boles, Wilma

This curriculum unit focuses on individual and personal freedoms as guaranteed by the U.S. Constitution and as interpreted by the courts. In particular, the unit which includes illustrated student materials and a teacher's guide, underscores the idea of fundamental rights as expressed through the concepts of liberty, justice, and equality. Through…

Development of Curriculum Units as Basic Course for Calculus Provided for Freshmen with Low Academic Achievement

ERIC Educational Resources Information Center

Lue, Yuang-Tswong

2015-01-01

This study was to design, develop, and investigate instructional units for freshmen with low academic achievement to learn before they study calculus. Because the concepts, skills, and theories of function are fundamental for the calculus course but the below average students were not familiar with the basic knowledge and ability in function when…

The California State Environmental Education Guide. A Curriculum Guide for Kindergarten through Sixth Grade.

ERIC Educational Resources Information Center

Sly, Carolie; And Others

The purpose of this guide is to provide teachers and other educators with classroom lessons and instructional techniques that build a fundamental understanding of the environment. The guide is aimed at grades kindergarten through sixth and consists of eight instructional units and six action projects. Each unit is organized around a theme and the…

Threat to Valued Elements of Life: The Experience of Dementia across Three Ethnic Groups

ERIC Educational Resources Information Center

Lawrence, Vanessa; Samsi, Kritika; Banerjee, Sube; Morgan, Craig; Murray, Joanna

2011-01-01

Purpose: There is a fundamental knowledge gap regarding the experience of dementia within minority ethnic groups in the United Kingdom and elsewhere. The present study examined the subjective reality of living with dementia from the perspective of people with dementia within the 3 largest ethnic groups in the United Kingdom. Design and Methods:…

Articulated, Performance-Based Instruction Objectives Guide for Air Conditioning, Refrigeration, and Heating (Environmental Control System Installer/Servicer). Edition I.

ERIC Educational Resources Information Center

Henderson, William Edward, Jr., Ed.

This articulation guide contains 17 units of instruction for the first year of a two-year vocational program designed to prepare the high school graduate to install, maintain, and repair various types of residential and commercial heating, air conditioning, and refrigeration equipment. The units are to introduce the student to fundamental theories…

Gestalt Principles in the Control of Motor Action

ERIC Educational Resources Information Center

Klapp, Stuart T.; Jagacinski, Richard J.

2011-01-01

We argue that 4 fundamental gestalt phenomena in perception apply to the control of motor action. First, a motor gestalt, like a perceptual gestalt, is holistic in the sense that it is processed as a single unit. This notion is consistent with reaction time results indicating that all gestures for a brief unit of action must be programmed prior to…

Combined effects of heat waves and droughts on avian communities across the conterminous United States

Treesearch

Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Brian D. Wardlow; Curtis H. Flather; Patrick D. Culbert; Volker C. Radeloff

2010-01-01

Increasing surface temperatures and climatic variability associated with global climate change are expected to produce more frequent and intense heat waves and droughts in many parts of the world. Our goal was to elucidate the fundamental, but poorly understood, effects of these extreme weather events on avian communities across the conterminous United States....

The Role and Purposes of Public Schools and Religious Fundamentalism: An International Human Rights Law Perspective

ERIC Educational Resources Information Center

Hodgson, Douglas Charles

2012-01-01

The question of what are today the legitimate and proper role and purposes of public schools can only be answered by a close examination and analysis of the human right to education which has been developed by such international organizations as the United Nations and the United Nations Educational, Scientific and Cultural Organization, and by…

Fuel System Services. An Instructor's Guide for a Program in Trade and Technical Education. Automotive Industries Occupations.

ERIC Educational Resources Information Center

New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

Designed to assist instructors in preparing secondary and adult students for employment in the field of fuel system services, this guide outlines eight units of instruction. The eight unit titles are (1) Introduction (overview of course content and requirements, and work/safety habits), (2) Minor Components, (3) Carburetor Fundamentals, (4)…

Physical fundamentals of criterial estimation of nitriding technology for parts of friction units

NASA Astrophysics Data System (ADS)

Kuksenova, L. I.; Gerasimov, S. A.; Lapteva, V. G.; Alekseeva, M. S.

2013-03-01

Characteristics of the structure and properties of surface layers of nitrided structural steels and alloys, which affect the level of surface fracture under friction, are studied. A generalized structural parameter for optimizing the nitriding process and a rapid method for estimating the quality of the surface layer of nitrided parts of friction units are developed.

Advanced Technical Data Study

DTIC Science & Technology

1975-01-29

will shut down automatically when condenser high pressure causes Pressure Limit Control high pressure switch to release. Press START switch (3...power cable (1) from facility pow- er. Troubleshoot cooling unit, for HI-LOW pressure switch repeated cutout. Refer to AGE ECU Cooling Unit...acti- vate when loss of air flow oc- curred, the pressure switch (3) failed to open circuit. Adjust or replace pressure switch . Refer to

Are We Facing a "Literacy Surplus" in the Workforces of the United States and Canada? Research Note.

ERIC Educational Resources Information Center

Sticht, Thomas G.

In the United States and Canada alike, expressions of concern over the fact that the demand for skilled workers far exceeds the current supply have been heard repeatedly. However, several studies would seem to indicate that, as familiar as these claims about the supply and demand for skilled workers may be, they are very contentious. If a Hudson…

Knowledge and Understanding of 21st Century Skills through Educator Externships: Programs in Southern New England

ERIC Educational Resources Information Center

Gibson-Cayouette, Lizann R.

2010-01-01

An acute shortage of a competent, highly-skilled workforce faces the United States workplace. Studies and reports from 1983 to present, repeatedly state that the education system in the United States must change to prepare the emergent workforce for success in the 21st century global challenges of both post-secondary education and the workplace.…

Comparative Characterization of Complete and Truncated Forms of Lactobacillus amylovorus α-Amylase and Role of the C-Terminal Direct Repeats in Raw-Starch Binding

PubMed Central

Rodriguez Sanoja, R.; Morlon-Guyot, J.; Jore, J.; Pintado, J.; Juge, N.; Guyot, J. P.

2000-01-01

Two constructs derived from the α-amylase gene (amyA) of Lactobacillus amylovorus were expressed in Lactobacillus plantarum, and their expression products were purified, characterized, and compared. These products correspond to the complete (AmyA) and truncated (AmyAΔ) forms of α-amylase; AmyAΔ lacks the 66-kDa carboxyl-terminal direct-repeating-unit region. AmyA and AmyAΔ exhibit similar amylase activities towards a range of soluble substrates (amylose, amylopectin and α-cyclodextrin, and soluble starch). The specific activities of the enzymes towards soluble starch are similar, but the KM and Vmax values of AmyAΔ were slightly higher than those of AmyA, whereas the thermal stability of AmyAΔ was lower than that of AmyA. In contrast to AmyA, AmyAΔ is unable to bind to β-cyclodextrin and is only weakly active towards glycogen. More striking is the fact that AmyAΔ cannot bind or hydrolyze raw starch, demonstrating that the carboxyl-terminal repeating-unit domain of AmyA is required for raw-starch binding activity. PMID:10919790

FAT1 Gene Alteration in Facioscapulohumeral Muscular Dystrophy Type 1.

PubMed

Park, Hyung Jun; Lee, Wookjae; Kim, Se Hoon; Lee, Jung Hwan; Shin, Ha Young; Kim, Seung Min; Park, Kee Duk; Lee, Ji Hyun; Choi, Young Chul

2018-03-01

Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is caused by contraction of the D4Z4 repeat array. Recent studies revealed that the FAT1 expression is associated with disease activity of FSHD, and the FAT1 alterations result in myopathy with a FSHD-like phenotype. We describe a 59-year-old woman with both contracted D4Z4 repeat units and a FAT1 mutation. Shoulder girdle muscle weakness developed at the age of 56 years, and was followed by proximal leg weakness. When we examined her at 59 years of age, she displayed asymmetric and predominant weakness of facial and proximal muscles. Muscle biopsy showed increased variation in fiber size and multifocal degenerating fibers with lymphocytic infiltration. Southern blot analysis revealed 8 D4Z4 repeat units, and targeted sequencing of modifier genes demonstrated the c.10331 A>G variant in the FAT1 gene. This FAT1 variant has previously been reported as pathogenic variant in a patient with FSHD-like phenotype. Our study is the first report of a FAT1 mutation in a FSHD1 patient, and suggests that FAT1 alterations might work as a genetic modifier. © Copyright: Yonsei University College of Medicine 2018.

Microgravity

NASA Image and Video Library

1998-07-01

The fundamental structural unit of chromatin and is the basis for organization within the genome by compaction of DNA within the nucleus of the cell and by making selected regions of chromosomes available for transcription and replication.

Nucleosome

NASA Technical Reports Server (NTRS)

1998-01-01

The fundamental structural unit of chromatin and is the basis for organization within the genome by compaction of DNA within the nucleus of the cell and by making selected regions of chromosomes available for transcription and replication.

Commentary: recent reforms in the British National Health Service--lessons for the United States.

PubMed Central

Holland, W W; Graham, C

1994-01-01

President Clinton recently announced his reform plan for health care in the United States. The United Kingdom, along with other countries, has already enacted reforms in an effort to overcome the basic problem of having insufficient funds to provide a health service to meet modern demands. This paper briefly describes the recent health reforms in the United Kingdom and highlights some lessons for the United States, which include the need to choose procedures that should be universally provided. Health reforms that involve some fundamental restructuring need to be evaluated everywhere and agreed to by the staff in advance. PMID:8296937

Use of the LUS in sequence allele designations to facilitate probabilistic genotyping of NGS-based STR typing results.

PubMed

Just, Rebecca S; Irwin, Jodi A

2018-05-01

Some of the expected advantages of next generation sequencing (NGS) for short tandem repeat (STR) typing include enhanced mixture detection and genotype resolution via sequence variation among non-homologous alleles of the same length. However, at the same time that NGS methods for forensic DNA typing have advanced in recent years, many caseworking laboratories have implemented or are transitioning to probabilistic genotyping to assist the interpretation of complex autosomal STR typing results. Current probabilistic software programs are designed for length-based data, and were not intended to accommodate sequence strings as the product input. Yet to leverage the benefits of NGS for enhanced genotyping and mixture deconvolution, the sequence variation among same-length products must be utilized in some form. Here, we propose use of the longest uninterrupted stretch (LUS) in allele designations as a simple method to represent sequence variation within the STR repeat regions and facilitate - in the nearterm - probabilistic interpretation of NGS-based typing results. An examination of published population data indicated that a reference LUS region is straightforward to define for most autosomal STR loci, and that using repeat unit plus LUS length as the allele designator can represent greater than 80% of the alleles detected by sequencing. A proof of concept study performed using a freely available probabilistic software demonstrated that the LUS length can be used in allele designations when a program does not require alleles to be integers, and that utilizing sequence information improves interpretation of both single-source and mixed contributor STR typing results as compared to using repeat unit information alone. The LUS concept for allele designation maintains the repeat-based allele nomenclature that will permit backward compatibility to extant STR databases, and the LUS lengths themselves will be concordant regardless of the NGS assay or analysis tools employed. Further, these biologically based, easy-to-derive designations uphold clear relationships between parent alleles and their stutter products, enabling analysis in fully continuous probabilistic programs that model stutter while avoiding the algorithmic complexities that come with string based searches. Though using repeat unit plus LUS length as the allele designator does not capture variation that occurs outside of the core repeat regions, this straightforward approach would permit the large majority of known STR sequence variation to be used for mixture deconvolution and, in turn, result in more informative mixture statistics in the near term. Ultimately, the method could bridge the gap from current length-based probabilistic systems to facilitate broader adoption of NGS by forensic DNA testing laboratories. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Improving patient handover between teams using a business improvement model: PDSA cycle.

PubMed

Luther, Vishal; Hammersley, Daniel; Chekairi, Ahmed

2014-01-01

Medical admission units are continuously under pressure to move patients off the unit to outlying medical wards and allow for new admissions. In a typical district general hospital, doctors working in these medical wards reported that, on average, three patients each week arrived from the medical admission unit before any handover was received, and a further two patients arrived without any handover at all. A quality improvement project was therefore conducted using a 'Plan, Do, Study, Act' cycle model for improvement to address this issue. P - Plan: as there was no framework to support doctors with handover, a series of standard handover procedures were designed. D - Do: the procedures were disseminated to all staff, and championed by key stakeholders, including the clinical director and matron of the medical admission unit. S - STUDY: Measurements were repeated 3 months later and showed no change in the primary end points. A - ACT: The post take ward round sheet was redesigned, creating a checkbox for a medical admission unit doctor to document that handover had occurred. Nursing staff were prohibited from moving the patient off the ward until this had been completed. This later evolved into a separate handover sheet. Six months later, a repeat study revealed that only one patient each week was arriving before or without a verbal handover. Using a 'Plan, Do, Study, Act' business improvement tool helped to improve patient care.

Quantum and Information Thermodynamics: A Unifying Framework Based on Repeated Interactions

NASA Astrophysics Data System (ADS)

Strasberg, Philipp; Schaller, Gernot; Brandes, Tobias; Esposito, Massimiliano

2017-04-01

We expand the standard thermodynamic framework of a system coupled to a thermal reservoir by considering a stream of independently prepared units repeatedly put into contact with the system. These units can be in any nonequilibrium state and interact with the system with an arbitrary strength and duration. We show that this stream constitutes an effective resource of nonequilibrium free energy, and we identify the conditions under which it behaves as a heat, work, or information reservoir. We also show that this setup provides a natural framework to analyze information erasure ("Landauer's principle") and feedback-controlled systems ("Maxwell's demon"). In the limit of a short system-unit interaction time, we further demonstrate that this setup can be used to provide a thermodynamically sound interpretation to many effective master equations. We discuss how nonautonomously driven systems, micromasers, lasing without inversion and the electronic Maxwell demon can be thermodynamically analyzed within our framework. While the present framework accounts for quantum features (e.g., squeezing, entanglement, coherence), we also show that quantum resources do not offer any advantage compared to classical ones in terms of the maximum extractable work.

Improving Photovoltaic Performance of a Fused-Ring Azepinedione Copolymer via a D-A-A Design.

PubMed

Zhang, Honghong; Li, Ting; Xiao, Zuo; Lei, Zhongli; Ding, Liming

2018-04-01

Two conjugated copolymer donors, PTTABDT and PBTTABDT, based on a fused-ring azepinedione acceptor unit, 5-(2-octyldodecyl)-4H-thieno[2',3':4,5]thieno[3,2-c]thieno[2',3':4,5]thieno[2,3-e]azepine-4,6(5H)-dione (TTA), are prepared. PTTABDT possesses a conventional donor-acceptor (D-A) structure with one TTA in the repeat unit, while PBTTABDT has a D-A-A structure with two TTAs in the repeat unit. Compared with PTTABDT, PBTTABDT shows a deeper highest occupied molecular orbital (HOMO) level, a narrower bandgap, and a higher hole mobility, and exhibits better performance in bulk heterojunction solar cells. Power conversion efficiencies of 6.18% and 7.81% are achieved from PTTABDT:PC 71 BM and PBTTABDT:PC 71 BM solar cells, respectively. The higher performance of PBTTABDT:PC 71 BM solar cells results from the enhanced open-circuit voltage (V oc ) and short-circuit current density (  J sc ). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recent developments in the theory of protein folding: searching for the global energy minimum.

PubMed

Scheraga, H A

1996-04-16

Statistical mechanical theories and computer simulation are being used to gain an understanding of the fundamental features of protein folding. A major obstacle in the computation of protein structures is the multiple-minima problem arising from the existence of many local minima in the multidimensional energy landscape of the protein. This problem has been surmounted for small open-chain and cyclic peptides, and for regular-repeating sequences of models of fibrous proteins. Progress is being made in resolving this problem for globular proteins.

Role of granulocyte colony-stimulating factor in human reproduction.

PubMed

Eftekhar, Maryam; Naghshineh, Elham; Khani, Parisa

2018-01-01

As new research reveals, granulocyte colony-stimulating factor (G-CSF) plays an effective role in pregnancy success, considering that it not only affects the embryo implantation and ovarian function but also it promotes endometrial thickening and improves the pathophysiology of endometriosis, which all fundamentally lead to reducing pregnancy loss. In this review, we focus on the role of G-CSF in human reproduction. We summarized its role in ovulation, luteinized unruptured follicle syndrome, poor responders, improving repeated in vitro fertilization failure, endometrial receptivity and treatment of thin endometrium, and recurrent spontaneous abortion.

48 CFR 9904.404-40 - Fundamental requirement.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., identifiability and controllability, the extent of integration or independence of constituent units). (3) The... repairs and maintenace to a tangible capital asset which either restore the asset to, or maintain it at...

48 CFR 9904.404-40 - Fundamental requirement.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., identifiability and controllability, the extent of integration or independence of constituent units). (3) The... repairs and maintenace to a tangible capital asset which either restore the asset to, or maintain it at...

48 CFR 9904.404-40 - Fundamental requirement.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., identifiability and controllability, the extent of integration or independence of constituent units). (3) The... repairs and maintenace to a tangible capital asset which either restore the asset to, or maintain it at...

40 CFR 62.14685 - May I conduct a repeat performance test to establish new operating limits?

Code of Federal Regulations, 2011 CFR

2011-07-01

... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Continuous Compliance...

40 CFR 62.14685 - May I conduct a repeat performance test to establish new operating limits?

Code of Federal Regulations, 2010 CFR

2010-07-01

... DESIGNATED FACILITIES AND POLLUTANTS Federal Plan Requirements for Commercial and Industrial Solid Waste Incineration Units That Commenced Construction On or Before November 30, 1999 Continuous Compliance...

Malaysia and the United States 2004-2005: The Best of Times?

DTIC Science & Technology

2005-02-01

SPECIAL ASSESSMENT F E B R U A R Y 2 0 0 5 The Asia-Pacific and the United States 2004–2005 Malaysia and the United States 2004–2005: The Best of...Times? I A N S T O R E Y K E Y F I N D I N G S l Malaysia and the United States have a robust relationship underpinned by strong fundamentals that...positives in the relationship, such as shared values and beliefs, and has praised Malaysia for its leadership role in Southeast Asia and the wider Islamic

The CODATA 2017 values of h, e, k, and N A for the revision of the SI

NASA Astrophysics Data System (ADS)

Newell, D. B.; Cabiati, F.; Fischer, J.; Fujii, K.; Karshenboim, S. G.; Margolis, H. S.; de Mirandés, E.; Mohr, P. J.; Nez, F.; Pachucki, K.; Quinn, T. J.; Taylor, B. N.; Wang, M.; Wood, B. M.; Zhang, Z.

2018-04-01

Sufficient progress towards redefining the International System of Units (SI) in terms of exact values of fundamental constants has been achieved. Exact values of the Planck constant h, elementary charge e, Boltzmann constant k, and Avogadro constant N A from the CODATA 2017 Special Adjustment of the Fundamental Constants are presented here. These values are recommended to the 26th General Conference on Weights and Measures to form the foundation of the revised SI.

Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of [alpha]- and PPII-helices

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

Larson, Matthew R.; Rajashankar, Kanagalaghatta R.; Patel, Manisha H.

2010-08-18

Streptococcus mutans antigen I/II (AgI/II) is a cell surface-localized protein adhesin that interacts with salivary components within the salivary pellicle. AgI/II contributes to virulence and has been studied as an immunological and structural target, but a fundamental understanding of its underlying architecture has been lacking. Here we report a high-resolution (1.8 {angstrom}) crystal structure of the A{sub 3}VP{sub 1} fragment of S. mutans AgI/II that demonstrates a unique fibrillar form (155 {angstrom}) through the interaction of two noncontiguous regions in the primary sequence. The A{sub 3} repeat of the alanine-rich domain adopts an extended {alpha}-helix that intertwines with the P{submore » 1} repeat polyproline type II (PPII) helix to form a highly extended stalk-like structure heretofore unseen in prokaryotic or eukaryotic protein structures. Velocity sedimentation studies indicate that full-length AgI/II that contains three A/P repeats extends over 50 nanometers in length. Isothermal titration calorimetry revealed that the high-affinity association between the A{sub 3} and P{sub 1} helices is enthalpically driven. Two distinct binding sites on AgI/II to the host receptor salivary agglutinin (SAG) were identified by surface plasmon resonance (SPR). The current crystal structure reveals that AgI/II family proteins are extended fibrillar structures with the number of alanine- and proline-rich repeats determining their length.« less

Systematics and biogeography of Orconectes, subgenus Trisellescens, in the southeastern United States, a test of morphology-based classification

Treesearch

Christopher A. Taylor; Susan B. Adams; Guenter A. Schuster

2014-01-01

Diagnosable taxonomic units are fundamental to conservation biology and management of resources and the need for sound science in both fields is more pressing for aquatic ecosystems. Within freshwater crayfishes, the North American genus Orconectes is one of the most diverse in the World. Accurate assessments of species level relationships and species boundaries within...

Fates of live trees retained in forest cutting units, western Cascade Range, Oregon.

Treesearch

P.E. Busby; P. Adler; T.L. Warren; F.J. Swanson

2006-01-01

To assess the fate of live trees retained in dispersed patterns across cutting units in the western Cascade Range of Oregon, we conducted repeat surveys (1993 and 2001) of sites cut as early as 1983. Our objectives in this study are to (1) survey survival and mortality of trees retained at the time of harvest, (2) describe temporal patterns of windthrow and other...

Web-Based Army Repeatable Lesson in Operational Combat (WARLOC)

DTIC Science & Technology

2014-06-01

United States Army B.A., St. John’s University, 1996 Austin T. Starken Captain, United States Army B.S., Florida Institute of Technology, 2005 Submitted...Simulation Games. New York, NY: Continuum International Publishing Group, 2012. [25] J. Peterson , Playing at the World: A History of Simulating Wars, People...Serious Games and Virtual Worlds in Education, Professional Development, and Healthcare. Ed. Hershey , PA: IGI Global, 2013. [Online]. Available

Analytical relationships for prediction of the mechanical properties of additively manufactured porous biomaterials.

PubMed

Zadpoor, Amir Abbas; Hedayati, Reza

2016-12-01

Recent developments in additive manufacturing techniques have motivated an increasing number of researchers to study regular porous biomaterials that are based on repeating unit cells. The physical and mechanical properties of such porous biomaterials have therefore received increasing attention during recent years. One of the areas that have revived is analytical study of the mechanical behavior of regular porous biomaterials with the aim of deriving analytical relationships that could predict the relative density and mechanical properties of porous biomaterials, given the design and dimensions of their repeating unit cells. In this article, we review the analytical relationships that have been presented in the literature for predicting the relative density, elastic modulus, Poisson's ratio, yield stress, and buckling limit of regular porous structures based on various types of unit cells. The reviewed analytical relationships are used to compare the mechanical properties of porous biomaterials based on different types of unit cells. The major areas where the analytical relationships have improved during the recent years are discussed and suggestions are made for future research directions. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3164-3174, 2016. © 2016 The Authors Journal of Biomedical Materials Research Part A Published by Wiley Periodicals, Inc.

Design issues concerning Iran`s Bushehr nuclear power plant VVER-1000 conversion

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

Carson, C.F.

On January 8, 1995, the Atomic Energy Organization of Iran (AEOI) signed a contract for $800 million with the Russian Federation Ministry for Atomic Energy (Minatom) to complete Bushehr nuclear power plant (BNPP) unit 1. The agreement called for a Russian VVER-1000/320 pressurized water reactor (PWR) to be successfully installed into the existing German-built BNPP facilities in 5 yr. System design differences, bomb damage, and environmental exposure are key issues with which Minatom must contend in order to fulfill the contract. The AEOI under the Shah of Iran envisioned Bushehr as the first of many nuclear power plants, with Iranmore » achieving 24 GW(electric) by 1993 and 34 GW(electric) by 2000. Kraftwerk Union AG (KWU) began construction of the two-unit plant near the Persian Gulf town of Halileh in 1975. Unit 1 was {approx}80% complete and unit 2 was {approx}50% complete when construction was interrupted by the 1979 Iranian Islamic revolution. Despite repeated AEOI attempts to lure KWU and other companies back to Iran to complete the plant, Western concerns about nuclear proliferation in Iran and repeated bombings of the plant during the 1980-1988 Iran-Iraq war dissuaded Germany from resuming construction.« less

Call to Adopt a Nominal Set of Astrophysical Parameters and Constants to Improve the Accuracy of Fundamental Physical Properties of Stars

NASA Astrophysics Data System (ADS)

Harmanec, Petr; Prša, Andrej

2011-08-01

The increasing precision of astronomical observations of stars and stellar systems is gradually getting to a level where the use of slightly different values of the solar mass, radius, and luminosity, as well as different values of fundamental physical constants, can lead to measurable systematic differences in the determination of basic physical properties. An equivalent issue with an inconsistent value of the speed of light was resolved by adopting a nominal value that is constant and has no error associated with it. Analogously, we suggest that the systematic error in stellar parameters may be eliminated by (1) replacing the solar radius R⊙ and luminosity L⊙ by the nominal values that are by definition exact and expressed in SI units: and ; (2) computing stellar masses in terms of M⊙ by noting that the measurement error of the product GM⊙ is 5 orders of magnitude smaller than the error in G; (3) computing stellar masses and temperatures in SI units by using the derived values and ; and (4) clearly stating the reference for the values of the fundamental physical constants used. We discuss the need and demonstrate the advantages of such a paradigm shift.

When Your Baby's in the NICU (Neonatal Intensive Care Unit)

MedlinePlus

... place? With equipment designed for infants and medical staff specially trained in newborn care, the NICU is ... without having to repeatedly stick the baby. NICU staff try to make the infants' stay in the ...

DNA CTG triplet repeats involved in dynamic mutations of neurologically related gene sequences form stable duplexes

NASA Technical Reports Server (NTRS)

Smith, G. K.; Jie, J.; Fox, G. E.; Gao, X.

1995-01-01

DNA triplet repeats, 5'-d(CTG)n and 5'-d(CAG)n, are present in genes which have been implicated in several neurodegenerative disorders. To investigate possible stable structures formed by these repeating sequences, we have examined d(CTG)n, d(CAG)n and d(CTG).d(CAG)n (n = 2 and 3) using NMR and UV optical spectroscopy. These studies reveal that single stranded (CTG)n (n > 2) forms stable, antiparallel helical duplexes, while the single stranded (CAG)n requires at least three repeating units to form a duplex. NMR and UV melting experiments show that the Tm increases in the order of [(CAG)3]2 < [(CTG)3]2 << (CAG)3.(CTG)3. The (CTG)3 duplex is stable and exhibits similar NMR spectra in solutions containing 0.1-4 M NaCl and at a pH range from 4.6 to 8.8. The (CTG)3 duplex, which contains multiple-T.T mismatches, displays many NMR spectral characteristics similar to those of B-form DNA. However, unique NOE and 1H-31P coupling patterns associated with the repetitive T.T mismatches in the CTG repeats are discerned. These results, in conjunction with recent in vitro studies suggest that longer CTG repeats may form hairpin structures, which can potentially cause interruption in replication, leading to dynamic expansion or deletion of triplet repeats.

Dithiopheneindenofluorene (TIF) Semiconducting Polymers with Very High Mobility in Field-Effect Transistors.

PubMed

Chen, Hu; Hurhangee, Michael; Nikolka, Mark; Zhang, Weimin; Kirkus, Mindaugas; Neophytou, Marios; Cryer, Samuel J; Harkin, David; Hayoz, Pascal; Abdi-Jalebi, Mojtaba; McNeill, Christopher R; Sirringhaus, Henning; McCulloch, Iain

2017-09-01

The charge-carrier mobility of organic semiconducting polymers is known to be enhanced when the energetic disorder of the polymer is minimized. Fused, planar aromatic ring structures contribute to reducing the polymer conformational disorder, as demonstrated by polymers containing the indacenodithiophene (IDT) repeat unit, which have both a low Urbach energy and a high mobility in thin-film-transistor (TFT) devices. Expanding on this design motif, copolymers containing the dithiopheneindenofluorene repeat unit are synthesized, which extends the fused aromatic structure with two additional phenyl rings, further rigidifying the polymer backbone. A range of copolymers are prepared and their electrical properties and thin-film morphology evaluated, with the co-benzothiadiazole polymer having a twofold increase in hole mobility when compared to the IDT analog, reaching values of almost 3 cm 2 V -1 s -1 in bottom-gate top-contact organic field-effect transistors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Harstad, E. N.; Harlow, Francis Harvey,; Schreyer, H. L.

Our goal is to develop constitutive relations for the behavior of a solid polymer during high-strain-rate deformations. In contrast to the classic thermodynamic techniques for deriving stress-strain response in static (equilibrium) circumstances, we employ a statistical-mechanics approach, in which we evolve a probability distribution function (PDF) for the velocity fluctuations of the repeating units of the chain. We use a Langevin description for the dynamics of a single repeating unit and a Lioville equation to describe the variations of the PDF. Moments of the PDF give the conservation equations for a single polymer chain embedded in other similar chains. Tomore » extract single-chain analytical constitutive relations these equations have been solved for representative loading paths. By this process we discover that a measure of nonuniform chain link displacement serves this purpose very well. We then derive an evolution equation for the descriptor function, with the result being a history-dependent constitutive relation.« less

Subnanometre-resolution structure of the doublet microtubule reveals new classes of microtubule-associated proteins

PubMed Central

Ichikawa, Muneyoshi; Liu, Dinan; Kastritis, Panagiotis L.; Basu, Kaustuv; Hsu, Tzu Chin; Yang, Shunkai; Bui, Khanh Huy

2017-01-01

Cilia are ubiquitous, hair-like appendages found in eukaryotic cells that carry out functions of cell motility and sensory reception. Cilia contain an intriguing cytoskeletal structure, termed the axoneme that consists of nine doublet microtubules radially interlinked and longitudinally organized in multiple specific repeat units. Little is known, however, about how the axoneme allows cilia to be both actively bendable and sturdy or how it is assembled. To answer these questions, we used cryo-electron microscopy to structurally analyse several of the repeating units of the doublet at sub-nanometre resolution. This structural detail enables us to unambiguously assign α- and β-tubulins in the doublet microtubule lattice. Our study demonstrates the existence of an inner sheath composed of different kinds of microtubule inner proteins inside the doublet that likely stabilizes the structure and facilitates the specific building of the B-tubule. PMID:28462916

The structure of cell adhesion molecule uvomorulin. Insights into the molecular mechanism of Ca2+-dependent cell adhesion.

PubMed Central

Ringwald, M; Schuh, R; Vestweber, D; Eistetter, H; Lottspeich, F; Engel, J; Dölz, R; Jähnig, F; Epplen, J; Mayer, S

1987-01-01

We have determined the amino acid sequence of the Ca2+-dependent cell adhesion molecule uvomorulin as it appears on the cell surface. The extracellular part of the molecule exhibits three internally repeated domains of 112 residues which are most likely generated by gene duplication. Each of the repeated domains contains two highly conserved units which could represent putative Ca2+-binding sites. Secondary structure predictions suggest that the putative Ca2+-binding units are located in external loops at the surface of the protein. The protein sequence exhibits a single membrane-spanning region and a cytoplasmic domain. Sequence comparison reveals extensive homology to the chicken L-CAM. Both uvomorulin and L-CAM are identical in 65% of their entire amino acid sequence suggesting a common origin for both CAMs. Images Fig. 1. Fig. 4. Fig. 7. PMID:3501370

The effect of repeated bouts of backward walking on physiologic efficiency.

PubMed

Childs, John D; Gantt, Christy; Higgins, Dan; Papazis, Janet A; Franklin, Ronald; Metzler, Terri; Underwood, Frank B

2002-08-01

Previous studies have demonstrated an increased energy expenditure with novel tasks. With practice, the energy cost decreases as the body more efficiently recruits motor units. This study examined whether one becomes more efficient after repeated bouts of backward walking. The subjects were 7 healthy subjects between the ages of 23 and 49 years. A backward walking speed was calculated to elicit a VO(2) equal to 60% of the VO(2)max. There were 18 training sessions at the prescribed walking speed 3 d x wk(-1) for 20 min x d(-1). The backward walking speed required to elicit a fixed VO(2) increased between weeks 4 and 6 of the training period. This finding suggests that backward walking is indeed a novel task and that motor learning occurs as a result of practice, leading to a more efficient recruitment of motor units.

Investigation of Micro-Scale Architectural Effects on Damage of Composites

NASA Technical Reports Server (NTRS)

Stier, Bertram; Bednarcyk, Brett A.; Simon, Jaan W.; Reese, Stefanie

2015-01-01

This paper presents a three-dimensional, energy based, anisotropic, stiffness reduction, progressive damage model for composite materials and composite material constituents. The model has been implemented as a user-defined constitutive model within the Abaqus finite element software package and applied to simulate the nonlinear behavior of a damaging epoxy matrix within a unidirectional composite material. Three different composite microstructures were considered as finite element repeating unit cells, with appropriate periodicity conditions applied at the boundaries. Results representing predicted transverse tensile, longitudinal shear, and transverse shear stress-strain curves are presented, along with plots of the local fields indicating the damage progression within the microstructure. It is demonstrated that the damage model functions appropriately at the matrix scale, enabling localization of the damage to simulate failure of the composite material. The influence of the repeating unit cell geometry and the effect of the directionality of the applied loading are investigated and discussed.

Physical and chemical properties of some new perfluoropolyalkylether lubricants prepared by direct fluorination

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.; Bierschenk, T. R.; Juhlke, T. J.; Kawa, H.; Lagow, R. J.

1993-01-01

A series of perfluoropolyalkylether (PFPAE) fluids was synthesized by direct fluorination. Viscosity-temperature properties, oxidation stabilities, oxidation-corrosion properties, bulk modulus, lubricity, surface tension and density were measured. It was shown that as the carbon to oxygen ratio in the polymer repeating unit decreases, the viscometric properties improve, the fluids may become poorer boundary lubricants, the bulk modulus increases, the surface tension increases and the fluid density increases. The presence of difluoromethylene oxide units in the polymer does not significantly lower the oxidation and oxidation-corrosion stabilities as long as the difluoromethylene oxide units are separated by other units.

Catecholamines of the adrenal medula and their morphological changes during adaptation to repeated immobilization stress

NASA Technical Reports Server (NTRS)

Kvetnansky, R.; Mitro, A.; Mikulaj, L.; Hocman, G.

1980-01-01

Changes of the adrenal medulla of rats were studied in the course of adaptation to repeated immobilization stress. An increase in the number of cells in the adrenal medulla was found in the adapted animals; this increase was confirmed by weight indices of the medulla and by cell counts per surface unit. Simultaneous karyometric measurements of the nuclei of adrenal medulla cells and an analysis of the catecholamine contents in the adrenals explain the increased activity of the adrenal medulla in the course of adaptation.

Why Industry Must Step In to Train Engineers.

ERIC Educational Resources Information Center

Business Week, 1981

1981-01-01

Suggests industrial training of Japanese engineers since engineering education in Japan focuses on abstract science and rote learning of fundamental principles and not on practical laboratory experiences characteristic of training in the United States. (SK)

Energy Adventure.

ERIC Educational Resources Information Center

Oak Ridge Associated Universities, TN.

Designed as an interdisciplinary, supplemental teaching guide, this document provides fundamental information about energy supply, use, and conservation and related learning activities for secondary students. Eight units address the following topics: energy history, petroleum, natural gas, coal, electricity, alternative sources, energy…

Heterogeneity of the Epstein-Barr Virus (EBV) Major Internal Repeat Reveals Evolutionary Mechanisms of EBV and a Functional Defect in the Prototype EBV Strain B95-8.

PubMed

Ba Abdullah, Mohammed M; Palermo, Richard D; Palser, Anne L; Grayson, Nicholas E; Kellam, Paul; Correia, Samantha; Szymula, Agnieszka; White, Robert E

2017-12-01

Epstein-Barr virus (EBV) is a ubiquitous pathogen of humans that can cause several types of lymphoma and carcinoma. Like other herpesviruses, EBV has diversified through both coevolution with its host and genetic exchange between virus strains. Sequence analysis of the EBV genome is unusually challenging because of the large number and lengths of repeat regions within the virus. Here we describe the sequence assembly and analysis of the large internal repeat 1 of EBV (IR1; also known as the BamW repeats) for more than 70 strains. The diversity of the latency protein EBV nuclear antigen leader protein (EBNA-LP) resides predominantly within the exons downstream of IR1. The integrity of the putative BWRF1 open reading frame (ORF) is retained in over 80% of strains, and deletions truncating IR1 always spare BWRF1. Conserved regions include the IR1 latency promoter (Wp) and one zone upstream of and two within BWRF1. IR1 is heterogeneous in 70% of strains, and this heterogeneity arises from sequence exchange between strains as well as from spontaneous mutation, with interstrain recombination being more common in tumor-derived viruses. This genetic exchange often incorporates regions of <1 kb, and allelic gene conversion changes the frequency of small regions within the repeat but not close to the flanks. These observations suggest that IR1-and, by extension, EBV-diversifies through both recombination and breakpoint repair, while concerted evolution of IR1 is driven by gene conversion of small regions. Finally, the prototype EBV strain B95-8 contains four nonconsensus variants within a single IR1 repeat unit, including a stop codon in the EBNA-LP gene. Repairing IR1 improves EBNA-LP levels and the quality of transformation by the B95-8 bacterial artificial chromosome (BAC). IMPORTANCE Epstein-Barr virus (EBV) infects the majority of the world population but causes illness in only a small minority of people. Nevertheless, over 1% of cancers worldwide are attributable to EBV. Recent sequencing projects investigating virus diversity to see if different strains have different disease impacts have excluded regions of repeating sequence, as they are more technically challenging. Here we analyze the sequence of the largest repeat in EBV (IR1). We first characterized the variations in protein sequences encoded across IR1. In studying variations within the repeat of each strain, we identified a mutation in the main laboratory strain of EBV that impairs virus function, and we suggest that tumor-associated viruses may be more likely to contain DNA mixed from two strains. The patterns of this mixing suggest that sequences can spread between strains (and also within the repeat) by copying sequence from another strain (or repeat unit) to repair DNA damage. Copyright © 2017 Ba abdullah et al.

The xyloglucan-cellulose assembly at the atomic scale.

PubMed

Hanus, Jaroslav; Mazeau, Karim

2006-05-01

The assembly of cell wall components, cellulose and xyloglucan (XG), was investigated at the atomistic scale using molecular dynamics simulations. A molecular model of a cellulose crystal corresponding to the allomorph Ibeta and exhibiting a flexible complex external morphology was employed to mimic the cellulose microfibril. The xyloglucan molecules considered were the three typical basic repeat units, differing only in the size of one of the lateral chain. All the investigated XG fragments adsorb nonspecifically onto cellulose fiber; multiple arrangements are equally probable, and every cellulose surface was capable of binding the short XG molecules. The following structural effects emerged: XG molecules that do not have any long side chains tended to adapt themselves nicely to the topology of the microfibril, forming a flat, outstretched conformation with all the sugar residues interacting with the surface. In contrast, the XG molecules, which have long side chains, were not able to adopt a flat conformation that would enable the interaction of all the XG residues with the surface. In addition to revealing the fundamental atomistic details of the XG adsorption on cellulose, the present calculations give a comprehensive understanding of the way the XG molecules can unsorb from cellulose to create a network that forms the cell wall. Our revisited view of the adsorption features of XG on cellulose microfibrils is consistent with experimental data, and a model of the network is proposed. Copyright (c) 2006 Wiley Periodicals, Inc.

Developmental Programming of Branching Morphogenesis in the Kidney

PubMed Central

Schneider, Laura; Al-Awqati, Qais

2015-01-01

The kidney developmental program encodes the intricate branching and organization of approximately 1 million functional units (nephrons). Branching regulation is poorly understood, as is the source of a 10-fold variation in nephron number. Notably, low nephron count increases the risk for developing hypertension and renal failure. To better understand the source of this variation, we analyzed the complete gestational trajectory of mouse kidney development. We constructed a computerized architectural map of the branching process throughout fetal life and found that organogenesis is composed of two distinct developmental phases, each with stage-specific rate and morphologic parameters. The early phase is characterized by a rapid acceleration in branching rate and by branching divisions that repeat with relatively reproducible morphology. The latter phase, however, is notable for a significantly decreased yet constant branching rate and the presence of nonstereotyped branching events that generate progressive variability in tree morphology until birth. Our map identifies and quantitates the contribution of four developmental mechanisms that guide organogenesis: growth, patterning, branching rate, and nephron induction. When applied to organs that developed under conditions of malnutrition or in the setting of growth factor mutation, our normative map provided an essential link between kidney architecture and the fundamental morphogenetic mechanisms that guide development. This morphogenetic map is expected to find widespread applications and help identify modifiable targets to prevent developmental programming of common diseases. PMID:25644110

Developmental Programming of Branching Morphogenesis in the Kidney.

PubMed

Sampogna, Rosemary V; Schneider, Laura; Al-Awqati, Qais

2015-10-01

The kidney developmental program encodes the intricate branching and organization of approximately 1 million functional units (nephrons). Branching regulation is poorly understood, as is the source of a 10-fold variation in nephron number. Notably, low nephron count increases the risk for developing hypertension and renal failure. To better understand the source of this variation, we analyzed the complete gestational trajectory of mouse kidney development. We constructed a computerized architectural map of the branching process throughout fetal life and found that organogenesis is composed of two distinct developmental phases, each with stage-specific rate and morphologic parameters. The early phase is characterized by a rapid acceleration in branching rate and by branching divisions that repeat with relatively reproducible morphology. The latter phase, however, is notable for a significantly decreased yet constant branching rate and the presence of nonstereotyped branching events that generate progressive variability in tree morphology until birth. Our map identifies and quantitates the contribution of four developmental mechanisms that guide organogenesis: growth, patterning, branching rate, and nephron induction. When applied to organs that developed under conditions of malnutrition or in the setting of growth factor mutation, our normative map provided an essential link between kidney architecture and the fundamental morphogenetic mechanisms that guide development. This morphogenetic map is expected to find widespread applications and help identify modifiable targets to prevent developmental programming of common diseases. Copyright © 2015 by the American Society of Nephrology.

Lipoteichoic acids are embedded in cell walls during logarithmic phase, but exposed on membrane vesicles in Lactobacillus gasseri JCM 1131T.

PubMed

Shiraishi, T; Yokota, S; Sato, Y; Ito, T; Fukiya, S; Yamamoto, S; Sato, T; Yokota, A

2018-06-15

Lipoteichoic acid (LTA) is a cell surface molecule specific to Gram-positive bacteria. How LTA localises on the cell surface is a fundamental issue in view of recognition and immunomodulation in hosts. In the present study, we examined LTA localisation using strain JCM 1131T of Lactobacillus gasseri, which is a human intestinal lactic acid bacterium, during various growth phases by immunoelectron microscopy. We first evaluated the specificity of anti-LTA monoclonal antibody clone 55 used as a probe. The glycerophosphate backbone comprising almost intact size (20 to 30 repeating units) of LTA was required for binding. The antibody did not bind to other cellular components, including wall-teichoic acid. Immunoelectron microscopy indicated that LTA was embedded in the cell wall during the logarithmic phase, and was therefore not exposed on the cell surface. Similar results were observed for Lactobacillus fermentum ATCC 9338 and Lactobacillus rhamnosus ATCC 7469T. By contrast, membrane vesicles were observed in the logarithmic phase of L. gasseri with LTA exposed on their surface. In the stationary and death phases, LTA was exposed on cell wall-free cell membrane generated by autolysis. The dramatic alternation of localisation in different growth phases and exposure on the surface of membrane vesicles should relate with complicated interaction between bacteria and host.

Functional Consequences of Repeated Organophosphate Exposure: Potential Non-Cholinergic Mechanisms

PubMed Central

Terry, A.V.

2012-01-01

The class of chemicals known as the “organophosphates” (OPs) comprises many of the most common agricultural and commercial pesticides that are used worldwide as well as the highly toxic chemical warfare agents. The mechanism of the acute toxicity of OPs in both target and non-target organisms is primarily attributed to inhibitory actions on various forms of cholinesterase leading to excessive peripheral and central cholinergic activity. However, there is now substantial evidence that this canonical (cholinesterase-based) mechanism cannot alone account for the wide-variety of adverse consequences of OP exposure that have been described, especially those associated with repeated exposures to levels that produce no overt signs of acute toxicity. This type of exposure has been associated with prolonged impairments in attention, memory, and other domains of cognition, as well as chronic illnesses where these symptoms are manifested (e.g., Gulf War Illness, Alzheimer’s disease). Due to their highly reactive nature, it is not surprising that OPs might alter the function of a number of enzymes and proteins (in addition to cholinesterase). However, the wide variety of long-term neuropsychiatric symptoms that have been associated with OPs suggests that some basic or fundamental neuronal process was adversely affected during the exposure period. The purpose of this review is to discuss several non-cholinesterase targets of OPs that might affect such fundamental processes and includes cytoskeletal and motor proteins involved in axonal transport, neurotrophins and their receptors, and mitochondria (especially their morphology and movement in axons). Potential therapeutic implications of these OP interactions are also discussed. PMID:22465060

The origin of the split B800 absorption peak in the LH2 complexes from Allochromatium vinosum.

PubMed

Löhner, Alexander; Carey, Anne-Marie; Hacking, Kirsty; Picken, Nichola; Kelly, Sharon; Cogdell, Richard; Köhler, Jürgen

2015-01-01

The absorption spectrum of the high-light peripheral light-harvesting (LH) complex from the photosynthetic purple bacterium Allochromatium vinosum features two strong absorptions around 800 and 850 nm. For the LH2 complexes from the species Rhodopseudomonas acidophila and Rhodospirillum molischianum, where high-resolution X-ray structures are available, similar bands have been observed and were assigned to two pigment pools of BChl a molecules that are arranged in two concentric rings (B800 and B850) with nine (acidophila) or eight (molischianum) repeat units, respectively. However, for the high-light peripheral LH complex from Alc. vinosum, the intruiging feature is that the B800 band is split into two components. We have studied this pigment-protein complex by ensemble CD spectroscopy and polarisation-resolved single-molecule spectroscopy. Assuming that the high-light peripheral LH complex in Alc. vinosum is constructed on the same modular principle as described for LH2 from Rps. acidophila and Rsp. molischianum, we used those repeat units as a starting point for simulating the spectra. We find the best agreement between simulation and experiment for a ring-like oligomer of 12 repeat units, where the mutual arrangement of the B800 and B850 rings resembles those from Rsp. molischianum. The splitting of the B800 band can be reproduced if both an excitonic coupling between dimers of B800 molecules and their interaction with the B850 manifold are taken into account. Such dimers predict an interesting apoprotein organisation as discussed below.

DRD4 Polymorphism Moderates the Effect of Alcohol Consumption on Social Bonding

PubMed Central

Creswell, Kasey G.; Sayette, Michael A.; Manuck, Stephen B.; Ferrell, Robert E.; Hill, Shirley Y.; Dimoff, John D.

2012-01-01

Development of interpersonal relationships is a fundamental human motivation, and behaviors facilitating social bonding are prized. Some individuals experience enhanced reward from alcohol in social contexts and may be at heightened risk for developing and maintaining problematic drinking. We employed a 3 (group beverage condition) ×2 (genotype) design (N = 422) to test the moderating influence of the dopamine D4 receptor gene (DRD4 VNTR) polymorphism on the effects of alcohol on social bonding. A significant gene x environment interaction showed that carriers of at least one copy of the 7-repeat allele reported higher social bonding in the alcohol, relative to placebo or control conditions, whereas alcohol did not affect ratings of 7-absent allele carriers. Carriers of the 7-repeat allele were especially sensitive to alcohol's effects on social bonding. These data converge with other recent gene-environment interaction findings implicating the DRD4 polymorphism in the development of alcohol use disorders, and results suggest a specific pathway by which social factors may increase risk for problematic drinking among 7-repeat carriers. More generally, our findings highlight the potential utility of employing transdisciplinary methods that integrate genetic methodologies, social psychology, and addiction theory to improve theories of alcohol use and abuse. PMID:22347363

DRD4 polymorphism moderates the effect of alcohol consumption on social bonding.

PubMed

Creswell, Kasey G; Sayette, Michael A; Manuck, Stephen B; Ferrell, Robert E; Hill, Shirley Y; Dimoff, John D

2012-01-01

Development of interpersonal relationships is a fundamental human motivation, and behaviors facilitating social bonding are prized. Some individuals experience enhanced reward from alcohol in social contexts and may be at heightened risk for developing and maintaining problematic drinking. We employed a 3 (group beverage condition) ×2 (genotype) design (N = 422) to test the moderating influence of the dopamine D4 receptor gene (DRD4 VNTR) polymorphism on the effects of alcohol on social bonding. A significant gene x environment interaction showed that carriers of at least one copy of the 7-repeat allele reported higher social bonding in the alcohol, relative to placebo or control conditions, whereas alcohol did not affect ratings of 7-absent allele carriers. Carriers of the 7-repeat allele were especially sensitive to alcohol's effects on social bonding. These data converge with other recent gene-environment interaction findings implicating the DRD4 polymorphism in the development of alcohol use disorders, and results suggest a specific pathway by which social factors may increase risk for problematic drinking among 7-repeat carriers. More generally, our findings highlight the potential utility of employing transdisciplinary methods that integrate genetic methodologies, social psychology, and addiction theory to improve theories of alcohol use and abuse.

Molecular tandem repeat strategy for elucidating mechanical properties of high-strength proteins

PubMed Central

Jung, Huihun; Pena-Francesch, Abdon; Saadat, Alham; Sebastian, Aswathy; Kim, Dong Hwan; Hamilton, Reginald F.; Albert, Istvan; Allen, Benjamin D.; Demirel, Melik C.

2016-01-01

Many globular and structural proteins have repetitions in their sequences or structures. However, a clear relationship between these repeats and their contribution to the mechanical properties remains elusive. We propose a new approach for the design and production of synthetic polypeptides that comprise one or more tandem copies of a single unit with distinct amorphous and ordered regions. Our designed sequences are based on a structural protein produced in squid suction cups that has a segmented copolymer structure with amorphous and crystalline domains. We produced segmented polypeptides with varying repeat number, while keeping the lengths and compositions of the amorphous and crystalline regions fixed. We showed that mechanical properties of these synthetic proteins could be tuned by modulating their molecular weights. Specifically, the toughness and extensibility of synthetic polypeptides increase as a function of the number of tandem repeats. This result suggests that the repetitions in native squid proteins could have a genetic advantage for increased toughness and flexibility. PMID:27222581

Plasmid P1 replication: negative control by repeated DNA sequences.

PubMed Central

Chattoraj, D; Cordes, K; Abeles, A

1984-01-01

The incompatibility locus, incA, of the unit-copy plasmid P1 is contained within a fragment that is essentially a set of nine 19-base-pair repeats. One or more copies of the fragment destabilizes the plasmid when present in trans. Here we show that extra copies of incA interfere with plasmid DNA replication and that a deletion of most of incA increases plasmid copy number. Thus, incA is not essential for replication but is required for its control. When cloned in a high-copy-number vector, pieces of the incA fragment that each contain only three repeats destabilize P1 plasmids efficiently. This result makes it unlikely that incA specifies a regulatory product. Our in vivo results suggest that the repeating DNA sequence itself negatively controls replication by titrating a P1-determined protein, RepA, that is essential for replication. Consistent with this hypothesis is the observation that the RepA protein binds to the incA fragment in vitro. Images PMID:6387706

Brittle deformation during Alpine basal accretion and the origin of seismicity nests above the subduction interface

NASA Astrophysics Data System (ADS)

Menant, Armel; Angiboust, Samuel; Monié, Patrick; Oncken, Onno; Guigner, Jean-Michel

2018-04-01

Geophysical observations on active subduction zones have evidenced high seismicity clusters at 20-40 km depth in the fore-arc region whose origin remains controversial. We report here field observations of pervasive pseudotachylyte networks (interpreted as evidence for paleo-seismicity) in the now-exhumed Valpelline continental unit (Dent Blanche complex, NW. Alps, Italy), a tectonic sliver accreted to the upper plate at c. 30 km depth during the Paleocene Alpine subduction. Pre-alpine granulite-facies paragneiss from the core of the Valpelline unit are crosscut by widespread, mm to cm-thick pseudotachylyte veins. Co-seismic heating and subsequent cooling led to the formation of Ti-rich garnet rims, ilmenite needles, Ca-rich plagioclase, biotite microliths and hercynite micro-crystals. 39Ar-40Ar dating yields a 51-54 Ma age range for these veins, thus suggesting that frictional melting events occurred near peak burial conditions while the Valpelline unit was already inserted inside the duplex structure. In contrast, the base of the Valpelline unit underwent synchronous ductile and brittle, seismic deformation under water-bearing conditions followed by a re-equilibration at c. 40 Ma (39Ar-40Ar on retrograded pseudotachylyte veins) during exhumation-related deformation. Calculated rheological profiles suggest that pseudotachylyte veins from the dry core of the granulite unit record upper plate micro-seismicity (Mw 2-3) formed under very high differential stresses (>500 MPa) while the sheared base of the unit underwent repeated brittle-ductile deformation at much lower differential stresses (<40 MPa) in a fluid-saturated environment. These results demonstrate that some of the seismicity clusters nested along and above the plate interface may reflect the presence of stiff tectonic slivers rheologically analogous to the Valpelline unit acting as repeatedly breaking asperities in the basal accretion region of active subduction zones.

Polymer matrix electroluminescent materials and devices

DOEpatents

Marrocco, III, Matthew L.; Motamedi, Farshad J [Claremont, CA; Abdelrazzaq, Feras Bashir [Covina, CA; Abdelrazzaq, legal representative, Bashir Twfiq

2012-06-26

Photoluminescent and electroluminescent compositions are provided which comprise a matrix comprising aromatic repeat units covalently coordinated to a phosphorescent or luminescent metal ion or metal ion complexes. Methods for producing such compositions, and the electroluminescent devices formed therefrom, are also disclosed.

Best Practices Handbook: Traffic Engineering in Range Networks

DTIC Science & Technology

2016-03-01

units of measurement. Measurement Methodology - A repeatable measurement technique used to derive one or more metrics of interest . Network...Performance measures - Metrics that provide quantitative or qualitative measures of the performance of systems or subsystems of interest . Performance Metric

Characterization of three DNA transposons in the Dutch elm disease fungi and evidence of repeat-induced point (RIP) mutations.

PubMed

Bouvet, Guillaume F; Jacobi, Volker; Bernier, Louis

2007-05-01

Transposable elements (TEs) are fundamental components of eukaryotic genomes and can contribute in various ways to genome plasticity and evolution. We describe here the first three DNA transposons in the Dutch elm disease (DED) pathogens Ophiostoma ulmi and O. novo-ulmi, named OPHIO1, OPHIO2 and OPHIO3. We demonstrate that OPHIO transposons, which show high homology to Fot1/pogo TEs within the Tc1/mariner superfamily, have different distribution patterns and specificity in the DED fungi and that interspecific hybrids could act as genetic bridges for transmission of TEs between closely related fungal species. OPHIO3 was found to have undergone repeat-induced point mutations (RIP). We have also developed a complementary method to Margolin's ratios based on the computation of cumulative transition scores (CTS) in order to visualize rapidly RIP signatures on individual DNA strands of OPHIO transposons and TEs found in other ascomycete fungi.

Generalized Functions for the Fractional Calculus

NASA Technical Reports Server (NTRS)

Lorenzo, Carl F.; Hartley, Tom T.

1999-01-01

Previous papers have used two important functions for the solution of fractional order differential equations, the Mittag-Leffler functionE(sub q)[at(exp q)](1903a, 1903b, 1905), and the F-function F(sub q)[a,t] of Hartley & Lorenzo (1998). These functions provided direct solution and important understanding for the fundamental linear fractional order differential equation and for the related initial value problem (Hartley and Lorenzo, 1999). This paper examines related functions and their Laplace transforms. Presented for consideration are two generalized functions, the R-function and the G-function, useful in analysis and as a basis for computation in the fractional calculus. The R-function is unique in that it contains all of the derivatives and integrals of the F-function. The R-function also returns itself on qth order differ-integration. An example application of the R-function is provided. A further generalization of the R-function, called the G-function brings in the effects of repeated and partially repeated fractional poles.

Drosophila melanogaster As a Model Organism to Study RNA Toxicity of Repeat Expansion-Associated Neurodegenerative and Neuromuscular Diseases

PubMed Central

Koon, Alex C.; Chan, Ho Yin Edwin

2017-01-01

For nearly a century, the fruit fly, Drosophila melanogaster, has proven to be a valuable tool in our understanding of fundamental biological processes, and has empowered our discoveries, particularly in the field of neuroscience. In recent years, Drosophila has emerged as a model organism for human neurodegenerative and neuromuscular disorders. In this review, we highlight a number of recent studies that utilized the Drosophila model to study repeat-expansion associated diseases (READs), such as polyglutamine diseases, fragile X-associated tremor/ataxia syndrome (FXTAS), myotonic dystrophy type 1 (DM1) and type 2 (DM2), and C9ORF72-associated amyotrophic lateral sclerosis/frontotemporal dementia (C9-ALS/FTD). Discoveries regarding the possible mechanisms of RNA toxicity will be focused here. These studies demonstrate Drosophila as an excellent in vivo model system that can reveal novel mechanistic insights into human disorders, providing the foundation for translational research and therapeutic development. PMID:28377694

Developing and Evaluating an Eighth Grade Curriculum Unit That Links Foundational Chemistry to Biological Growth: Paper 5--Using Teacher Measures to Evaluate the Promise of the Intervention

ERIC Educational Resources Information Center

Flanagan, Jean C.; Herrmann-Abell, Cari F.; Roseman, Jo Ellen

2013-01-01

AAAS (American Association for the Advancement of Science) is collaborating with BSCS (Biological Sciences Curriculum Study) in the development of a curriculum unit for eighth grade students that connects fundamental chemistry and biology concepts to better prepare them for high school biology. Recognizing that teachers play an influential role in…